query: Varying expression levels of EBI2 affect the positioning and migration of B cells.

title: Guidance of B cells by the orphan G protein-coupled receptor EBI2 shapes humoral immune responses.

text: Humoral immunity depends on both rapid and long-term antibody production against invading pathogens. This is achieved by the generation of spatially distinct extrafollicular plasmablast and follicular germinal center (GC) B cell populations, but the signals that guide responding B cells to these alternative compartments have not been fully elucidated. Here, we show that expression of the orphan G protein-coupled receptor Epstein-Barr virus-induced gene 2 (EBI2, also known as GPR183) by activated B cells was essential for their movement to extrafollicular sites and induction of early plasmablast responses. Conversely, downregulation of EBI2 enabled B cells to access the center of follicles and promoted efficient GC formation. EBI2 therefore provides a previously uncharacterized dimension to B cell migration that is crucial for coordinating rapid versus long-term antibody responses.

title: 7α, 25-dihydroxycholesterol-mediated activation of EBI2 in immune regulation and diseases

text: EBI2, aka GPR183, is a G-couple receptor originally identified in 1993 as one of main genes induced in Burkitt's lymphoma cell line BL41 by Epstein-Barr virus (EBV) infection. After it was reported in 2009 that the receptor played a key role in regulating B cell migration and responses, we initiated an effort in looking for its endogenous ligand. In 2011 we and another group reported the identification of 7α, 25-dihydroxyxcholesterol (7α, 25-OHC), an oxysterol, as the likely physiological ligand of EBI2. A few subsequently published studies further elucidated how 7α, 25-OHC bound to EBI2, and how a gradient of 7α, 25-OHC could be generated in vivo and regulated migration, activation, and functions of B cells, T cells, dendritic cells (DCs), monocytes/macrophages, and astrocytes. The identification of 7α, 25-OHC as a G protein-coupled receptor ligand revealed a previously unknown signaling system of oxysterols, a class of molecules which exert profound biological functions. Dysregulation of the synthesis or functions of these molecules is believed to contribute to inflammation and autoimmune diseases, cardiovascular diseases, neurodegenerative diseases, cancer as well as metabolic diseases such as diabetes, obesity, and dyslipidemia. Therefore EBI2 may represent a promising target for therapeutic interventions for human diseases.

title: Finding the right niche: B-cell migration in the early phases of T-dependent antibody responses.

text: Humoral immune responses depend on B cells encountering antigen, interacting with helper T cells, proliferating and differentiating into low-affinity plasma cells or, after organizing into a germinal center (GC), high-affinity plasma cells and memory B cells. Remarkably, each of these events occurs in association with distinct stromal cells in separate subcompartments of the lymphoid tissue. B cells must migrate from niche to niche in a rapid and highly regulated manner to successfully mount a response. The chemokine, CXCL13, plays a central role in guiding B cells to follicles whereas T-zone chemokines guide activated B cells to the T zone. Sphingosine-1-phosphate (S1P) promotes cell egress from the tissue, as well as marginal-zone B-cell positioning in the spleen. Recent studies have identified a role for the orphan receptor, EBV-induced molecule 2 (EBI2; GPR183), in guiding activated B cells to inter and outer follicular niche(s) and down-regulation of this receptor is essential for organizing cells into GCs. In this review, we discuss current understanding of the roles played by chemokines, S1P and EBI2 in the migration events that underlie humoral immune responses.

title: Role of NF-kappa B in cell survival and transcription of latent membrane protein 1-expressing or Epstein-Barr virus latency III-infected cells.

text: Epstein-Barr virus (EBV) latency III infection converts B lymphocytes into lymphoblastoid cell lines (LCLs) by expressing EBV nuclear and membrane proteins, EBNAs, and latent membrane proteins (LMPs), which regulate transcription through Notch and tumor necrosis factor receptor pathways. The role of NF-kappa B in LMP1 and overall EBV latency III transcriptional effects was investigated by treating LCLs with BAY11-7082 (BAY11). BAY11 rapidly and irreversibly inhibited NF-kappa B, decreased mitochondrial membrane potential, induced apoptosis, and altered LCL gene expression. BAY11 effects were similar to those of an NF-kappa B inhibitor, Delta N-I kappa B alpha, in effecting decreased JNK1 expression and in microarray analyses. More than 80% of array elements that decreased with Delta N-I kappa B alpha expression decreased with BAY11 treatment. Newly identified NF-kappa B-induced, LMP1-induced, and EBV-induced genes included pleckstrin, Jun-B, c-FLIP, CIP4, and I kappa B epsilon. Of 776 significantly changed array elements, 134 were fourfold upregulated in EBV latency III, and 74 were fourfold upregulated with LMP1 expression alone, whereas only 28 were more than fourfold downregulated by EBV latency III. EBV latency III-regulated gene products mediate cell migration (EBI2, CCR7, RGS1, RANTES, MIP1 alpha, MIP1 beta, CXCR5, and RGS13), antigen presentation (major histocompatibility complex proteins and JAW1), mitogen-activated protein kinase pathway (DUSP5 and p62Dok), and interferon (IFN) signaling (IFN-gamma R alpha, IRF-4, and STAT1). Comparison of EBV latency III LCL gene expression to immunoglobulin M (IgM)-stimulated B cells, germinal-center B cells, and germinal-center-derived lymphomas clustered LCLs with IgM-stimulated B cells separately from germinal-center cells or germinal-center lymphoma cells. Expression of IRF-2, AIM1, ASK1, SNF2L2, and components of IFN signaling pathways further distinguished EBV latency III-infected B cells from IgM-stimulated or germinal-center B cells.

title: Matrix Metalloproteinase 1 Is Necessary for the Migration of Human Bone Marrow-Derived Mesenchymal Stem Cells Toward Human Glioma

text: Human mesenchymal stem cells (MSCs) have increasingly been used as cellular vectors for the delivery of therapeutic genes to tumors. However, the precise mechanism of mobilization remains poorly defined. In this study, MSCs that expressed similar cell surface markers and exhibited multilineage differentiation potentials were isolated from various donors. Interestingly, different MSC isolates displayed differential migration ability toward human glioma cells. We hypothesized that distinct molecular signals may be involved in the varied tumor tropisms exhibited by different MSC isolates. To test this hypothesis, gene expression profiles of tumor-trophic MSCs were compared with those of non-tumor-trophic MSCs. Among the various differentially regulated genes, matrix metalloproteinase one (MMP1) gene expression and its protein activities were enhanced by 27-fold and 21-fold, respectively, in highly migrating MSCs compared with poorly migrating MSCs. By contrast, there was no change in the transcriptional levels of other MMPs. Functional inactivation of MMP1 abrogated the migratory potential of MSCs toward glioma-conditioned medium. Conversely, the nonmigratory phenotype of poorly migrating MSC could be rescued in the presence of either recombinant MMP1 or conditioned medium from the highly migrating MSCs. Ectopic expression of MMP1 in these poorly migrating cells also rendered the cells responsive to the signaling cues from the glioma cells in vivo. However, blocking the interaction of MMP1 and its cognate receptor PAR1 effectively diminished the migratory ability of MSCs. Taken together, this study provides, for the first time, supporting evidence that MMP1 is critically involved in the migration capacity of MSCs, acting through the MMP1/PAR1 axis.

title: Who is where at risk for Chronic Obstructive Pulmonary Disease? A spatial epidemiological analysis of health insurance claims for COPD in Northeastern Germany

text:
BACKGROUND Chronic obstructive pulmonary disease (COPD) has a high prevalence rate in Germany and a further increase is expected within the next years. Although risk factors on an individual level are widely understood, only little is known about the spatial heterogeneity and population-based risk factors of COPD. Background knowledge about broader, population-based processes could help to plan the future provision of healthcare and prevention strategies more aligned to the expected demand. The aim of this study is to analyze how the prevalence of COPD varies across northeastern Germany on the smallest spatial-scale possible and to identify the location-specific population-based risk factors using health insurance claims of the AOK Nordost.
 METHODS To visualize the spatial distribution of COPD prevalence at the level of municipalities and urban districts, we used the conditional autoregressive Besag-York-Mollié (BYM) model. Geographically weighted regression modelling (GWR) was applied to analyze the location-specific ecological risk factors for COPD.
 RESULTS The sex- and age-adjusted prevalence of COPD was 6.5% in 2012 and varied widely across northeastern Germany. Population-based risk factors consist of the proportions of insurants aged 65 and older, insurants with migration background, household size and area deprivation. The results of the GWR model revealed that the population at risk for COPD varies considerably across northeastern Germany.
 CONCLUSION Area deprivation has a direct and an indirect influence on the prevalence of COPD. Persons ageing in socially disadvantaged areas have a higher chance of developing COPD, even when they are not necessarily directly affected by deprivation on an individual level. This underlines the importance of considering the impact of area deprivation on health for planning of healthcare. Additionally, our results reveal that in some parts of the study area, insurants with migration background and persons living in multi-persons households are at elevated risk of COPD.

title: Concentration Sensing by the Moving Nucleus in Cell Fate Determination: A Computational Analysis

text: During development of the vertebrate neuroepithelium, the nucleus in neural progenitor cells (NPCs) moves from the apex toward the base and returns to the apex (called interkinetic nuclear migration) at which point the cell divides. The fate of the resulting daughter cells is thought to depend on the sampling by the moving nucleus of a spatial concentration profile of the cytoplasmic Notch intracellular domain (NICD). However, the nucleus executes complex stochastic motions including random waiting and back and forth motions, which can expose the nucleus to randomly varying levels of cytoplasmic NICD. How nuclear position can determine daughter cell fate despite the stochastic nature of nuclear migration is not clear. Here we derived a mathematical model for reaction, diffusion, and nuclear accumulation of NICD in NPCs during interkinetic nuclear migration (INM). Using experimentally measured trajectory-dependent probabilities of nuclear turning, nuclear waiting times and average nuclear speeds in NPCs in the developing zebrafish retina, we performed stochastic simulations to compute the nuclear trajectory-dependent probabilities of NPC differentiation. Comparison with experimentally measured nuclear NICD concentrations and trajectory-dependent probabilities of differentiation allowed estimation of the NICD cytoplasmic gradient. Spatially polarized production of NICD, rapid NICD cytoplasmic consumption and the time-averaging effect of nuclear import/export kinetics are sufficient to explain the experimentally observed differentiation probabilities. Our computational studies lend quantitative support to the feasibility of the nuclear concentration-sensing mechanism for NPC fate determination in zebrafish retina.

title: OncomiR-196 promotes an invasive phenotype in oral cancer through the NME4-JNK-TIMP1-MMP signaling pathway

text:
BACKGROUND MicroRNA-196 (miR-196), which is highly up-regulated in oral cancer cells, has been reported to be aberrantly expressed in several cancers; however, the significance of miR-196 in oral cancer has not yet been addressed.
 METHODS Cellular functions in response to miR-196 modulation were examined, including cell growth, migration, invasion and radio/chemosensitivity. Algorithm-based studies were used to identify the regulatory target of miR-196. The miR-196 target gene and downstream molecular mechanisms were confirmed by RT-qPCR, western blot, luciferase reporter and confocal microscopy analyses. miR-196 expression was determined in paired cancer and adjacent normal tissues from oral cancer patients.
 RESULTS Both miR-196a and miR-196b were highly over-expressed in the cancer tissue and correlated with lymph node metastasis (P = 0.001 and P = 0.006, respectively). Functionally, miR-196 actively promoted cell migration and invasion without affecting cell growth. Mechanistically, miR-196 performed it's their function by inhibiting NME4 expression and further activating p-JNK, suppressing TIMP1, and augmenting MMP1/9.
 CONCLUSION miR-196 contributes to oral cancer by promoting cell migration and invasion. Clinically, miR-196a/b was significantly over-expressed in the cancer tissues and correlated with lymph node metastasis. Thus, our findings provide new knowledge of the underlying mechanism of cancer metastasis. miR-196 may serve as a promising marker for better oral cancer management.

title: The epidemiology of sexually transmitted co-infections in HIV-positive and HIV-negative African-Caribbean women in Toronto

text:
BACKGROUND HIV disproportionately affects African-Caribbean women in Canada but the frequency and distribution of sexually transmitted infections in this community have not been previously studied.
 METHODS We recruited women based on HIV status through a Toronto community health centre. Participants completed a socio-behavioural questionnaire using Audio Computer Assisted Self-Interview (ACASI) and provided blood for syphilis, HIV, hepatitis B and C, herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), and human cytomegalovirus (CMV) serology, urine for chlamydia and gonorrhea molecular testing and vaginal secretions for bacterial vaginosis (BV) and human papillomavirus (HPV). Differences in prevalence were assessed for statistical significance using chi-square.
 RESULTS We recruited 126 HIV-positive and 291 HIV-negative women, with a median age of 40 and 31 years, respectively (p < 0.001). Active HBV infection and lifetime exposure to HBV infection were more common in HIV-positive women (4.8% vs. 0.34%, p = 0.004; and 47.6% vs. 21.2%, p < 0.0001), as was a self-reported history of HBV vaccination (66.1% vs. 44.0%, p = 0.0001). Classical STIs were rare in both groups; BV prevalence was low and did not vary by HIV status. HSV-2 infection was markedly more frequent in HIV-positive (86.3%) than HIV-negative (46.6%) women (p < 0.0001). Vaginal HPV infection was also more common in HIV-positive than in HIV-negative women (50.8% vs. 22.6%, p < 0.0001) as was infection with high-risk oncogenic HPV types (48.4% vs. 17.3%, p < 0.0001).
 CONCLUSIONS Classical STIs were infrequent in this clinic-based population of African-Caribbean women in Toronto. However, HSV-2 prevalence was higher than that reported in previous studies in the general Canadian population and was strongly associated with HIV infection, as was infection with hepatitis B and HPV.

title: Effects of Bifidobacterium animalis administered during lactation on allergic and autoimmune responses in rodents.

text: Probiotics are promoted as being beneficial to health and positive effects on the immune system have been reported. Beneficial immune effects have been attributed to several mechanisms, including stimulating T helper 1 (Th1) immunity. To explore the effects of the probiotic Bifidobacterium animalis on Th1- and Th2-mediated immune responses, two different animal models representing either Th1- or Th2-mediated immune responses were used: a rat model for experimental autoimmune encephalomyelitis (EAE) (Th1) and a mouse model for respiratory allergy induced by ovalbumin (OVA) (Th2). B. animalis administration started when the mice or rats were 2 weeks old. Respiratory allergy or EAE were induced when the animals were 6-7 weeks old. In the allergy model, B. animalis modestly reduced the number of infiltrating eosinophils and lymphocytes in the lungs, but no effects on allergen-specific serum immunoglobulin E levels were found. Cytokine profiles assessed after culturing spleen cells with the mitogen concanvalin A (ConA) showed that B. animalis skewed the Th1/Th2 balance towards Th1 in females. However, allergen-induced cytokine production in females was not affected by B. animalis. In males, B. animalis significantly decreased ConA-induced interleukin-13 and a trend towards lower levels of OVA-induced Th2 cytokines. In the EAE model, B. animalis significantly reduced the duration of clinical symptoms by almost 2 days in males and improved the body weight gain during the experimental period compared with the control group. Our data show that B. animalis reduced several immune parameters in the allergy as well as in the autoimmunity model.

title: Tetraspanin 7 (TSPAN7) expression is upregulated in multiple myeloma patients and inhibits myeloma tumour development in vivo.

text:
BACKGROUND Increased expression of the tetraspanin TSPAN7 has been observed in a number of cancers; however, it is unclear how TSPAN7 plays a role in cancer progression.
 METHODS We investigated the expression of TSPAN7 in the haematological malignancy multiple myleoma (MM) and assessed the consequences of TSPAN7 expression in the adhesion, migration and growth of MM plasma cells (PC) in vitro and in bone marrow (BM) homing and tumour growth in vivo. Finally, we characterised the association of TSPAN7 with cell surface partner molecules in vitro.
 RESULTS TSPAN7 was found to be highly expressed at the RNA and protein level in CD138(+) MM PC from approximately 50% of MM patients. TSPAN7 overexpression in the murine myeloma cell line 5TGM1 significantly reduced tumour burden in 5TGM1/KaLwRij mice 4 weeks after intravenous adminstration of 5TGM1 cells. While TSPAN7 overexpression did not affect cell proliferation in vitro, TSPAN7 increased 5TGM1 cell adhesion to BM stromal cells and transendothelial migration. In addition, TSPAN7 was found to associate with the molecular chaperone calnexin on the cell surface.
 CONCLUSION These results suggest that elevated TSPAN7 may be associated with better outcomes for up to 50% of MM patients.

title: A talin-dependent LFA-1 focal zone is formed by rapidly migrating T lymphocytes

text: Cells such as fibroblasts and endothelial cells migrate through the coordinated responses of discrete integrin-containing focal adhesions and complexes. In contrast, little is known about the organization of integrins on the highly motile T lymphocyte. We have investigated the distribution, activity, and cytoskeletal linkage of the integrin lymphocyte function associated antigen-1 (LFA-1) on human T lymphocytes migrating on endothelial cells and on ligand intercellular adhesion molecule-1 (ICAM-1). The pattern of total LFA-1 varies from low expression in the lamellipodia to high expression in the uropod. However, high affinity, clustered LFA-1 is restricted to a mid-cell zone that remains stable over time and over a range of ICAM-1 densities. Talin is essential for the stability and formation of the LFA-1 zone. Disruption of the talin–integrin link leads to loss of zone integrity and a substantial decrease in speed of migration on ICAM-1. This adhesive structure, which differs from the previously described integrin-containing attachments displayed by many other cell types, we have termed the “focal zone. ”

title: Lpd depletion reveals that SRF specifies radial versus tangential migration of pyramidal neurons

text: During corticogenesis, pyramidal neurons (∼80% of cortical neurons) arise from the ventricular zone, pass through a multipolar stage to become bipolar and attach to radial glia, and then migrate to their proper position within the cortex. As pyramidal neurons migrate radially, they remain attached to their glial substrate as they pass through the subventricular and intermediate zones, regions rich in tangentially migrating interneurons and axon fibre tracts. We examined the role of lamellipodin (Lpd), a homologue of a key regulator of neuronal migration and polarization in Caenorhabditis elegans, in corticogenesis. Lpd depletion caused bipolar pyramidal neurons to adopt a tangential, rather than radial-glial, migration mode without affecting cell fate. Mechanistically, Lpd depletion reduced the activity of SRF, a transcription factor regulated by changes in the ratio of polymerized to unpolymerized actin. Therefore, Lpd depletion exposes a role for SRF in directing pyramidal neurons to select a radial migration pathway along glia rather than a tangential migration mode.

title: Positive feedback between PU.1 and the cell cycle controls myeloid differentiation.

text: Regulatory gene circuits with positive-feedback loops control stem cell differentiation, but several mechanisms can contribute to positive feedback. Here, we dissect feedback mechanisms through which the transcription factor PU.1 controls lymphoid and myeloid differentiation. Quantitative live-cell imaging revealed that developing B cells decrease PU.1 levels by reducing PU.1 transcription, whereas developing macrophages increase PU.1 levels by lengthening their cell cycles, which causes stable PU.1 accumulation. Exogenous PU.1 expression in progenitors increases endogenous PU.1 levels by inducing cell cycle lengthening, implying positive feedback between a regulatory factor and the cell cycle. Mathematical modeling showed that this cell cycle-coupled feedback architecture effectively stabilizes a slow-dividing differentiated state. These results show that cell cycle duration functions as an integral part of a positive autoregulatory circuit to control cell fate.

title: Studies of nuclear and cytoplasmic behaviour during the five mitotic cycles that precede gastrulation in Drosophila embryogenesis.

text: Using differential interference contrast optics, combined with cinematography, we have studied the morphological changes that the living, syncytial embryo undergoes from stage 10 through 14 of Drosophila embryogenesis, that is just prior to and during formation of the cellular blastoderm. We have supplemented these studies with data collected from fixed, stained, whole embryos. The following information has been obtained. The average duration of nuclear cycles 10, 11, 12 and 13 is about 9, 10, 12 and 21 min, respectively (25 degrees C). In these four cycles, the duration of that portion of the mitotic period that lacks a discrete nuclear envelope is 3, 3, 3 and 5 min, respectively. The length of nuclear cycle 14 varies in a position-specific manner throughout the embryo, the shortest cycles being of 65 min duration. During nuclear cycles 10 through 13, it is commonly observed in living embryos that the syncytial blastoderm nuclei enter (and leave) mitosis in one of two waves that originate nearly simultaneously from the opposite anterior and posterior poles of the embryo, and terminate in its midregion. From our preparations of quick-frozen embryos, we estimate that these mitotic waves take on average about half a minute to travel over the embryonic surface from pole to equator. The yolk nuclei, which remain in the core of the embryo when the rest of the nuclei migrate to the periphery, divide in synchrony with the migrating nuclei at nuclear cycles 8 and 9, and just after the now peripherally located nuclei at nuclear cycle 10. After cycle 10, these yolk nuclei cease dividing and become polyploid. The syncytial embryo has at least three distinct levels of cytoskeletal organization: structured domains of cytoplasm are organized around each blastoderm nucleus; radially directed tracks orient colchicine-sensitive saltatory transport throughout the peripheral cytoplasm; and a long-range organization of the core of the embryo makes possible coherent movements of the large inner yolk mass in concert with each nuclear cycle. This highly organized cytoplasm may be involved in providing positional information for the important process of nuclear determination that is known to occur during these stages.

title: Immunophenotypic analysis of AIDS-related diffuse large B-cell lymphoma and clinical implications in patients from AIDS malignancies consortium clinical trials 010 and 034

text:
PURPOSE Diffuse large B-cell lymphoma (DLBCL) represents a clinically heterogeneous disease. Models based on immunohistochemistry predict clinical outcome. These include subdivision into germinal center (GC) versus non-GC subtypes; proliferation index (measured by expression of Ki-67), and expression of BCL-2, FOXP1, or B-lymphocyte-induced maturation protein (Blimp-1)/PRDM1. We sought to determine whether immunohistochemical analyses of biopsies from patients with DLBCL having HIV infection are similarly relevant for prognosis.
 PATIENTS AND METHODS We examined 81 DLBCLs from patients with AIDS in AMC010 (cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP] v CHOP-rituximab) and AMC034 (etoposide, doxorubicin, vincristine, prednisone, and dose-adjusted cyclophosphamide plus rituximab concurrent v sequential) clinical trials and compared the immunophenotype with survival data, Epstein-Barr virus (EBV) positivity, and CD4 counts.
 RESULTS The GC and non-GC subtypes of DLBCL did not differ significantly with respect to overall survival or CD4 count at cancer presentation. EBV could be found in both subtypes of DLBCL, although less frequently in the GC subtype, and did not affect survival. Expression of FOXP1, Blimp-1/PRDM1, or BCL-2 was not correlated with the outcome in patients with AIDS-related DLBCL.
 CONCLUSION These data indicate that with current treatment strategies for lymphoma and control of HIV infection, commonly used immunohistochemical markers may not be clinically relevant in HIV-infected patients with DLBCL. The only predictive immunohistochemical marker was found to be Ki-67, where a higher proliferation index was associated with better survival, suggesting a better response to therapy in patients whose tumors had higher proliferation rates.

title: TGF‐β‐mediated exosomal lnc‐MMP2‐2 regulates migration and invasion of lung cancer cells to the vasculature by promoting MMP2 expression

text: Previous studies indicated that transforming growth factor (TGF)-β-mediated exosomal microRNAs (miRNAs) regulate the migration and invasion of lung cancer cells; however, whether and how TGF-β-mediated exosomal long noncoding (lnc) RNAs regulate migration and invasion of lung cancer cells remains unclear. Here, coculture experiments showed that TGF-β pretreatment increased the migration and invasion potential of lung cancer cells and TGF-β pretreated A549 cells increases vascular permeability. Furthermore, we found that TGF-β-mediated exosomes, as carriers of intercellular communication, regulated lung cancer invasion, and vascular permeability. Transcriptional analysis also revealed that lnc-MMP2-2 was highly enriched in TGF-β-mediated exosomes and might function by increasing the expression of matrix metalloproteinase (MMP)2 through its enhancer activity, with ectopic expression and silencing of lnc-MMP2-2 affecting lung cancer invasion and vascular permeability. Additionally, lnc-MMP2-2 and MMP2 expression was assessed semiquantitatively, and tissue-specific correlations between lnc-MMP2-2 and MMP2 expression were evaluated. These results suggested that exosomal lnc-MMP2-2 might regulate the migration and invasion of lung cancer cells into the vasculature by promoting MMP2 expression, suggesting this lncRNA as a novel therapeutic target and predictive marker of tumor metastasis in lung cancer.

title: Keeping your senescent cells under control

text: Cellular senescence is a stable form of cell-cycle arrest which is thought to limit the proliferative potential of premalignant cells [1]. The senescence phenotype was initially described by Hayflick and Moorhead in 1961 on human fibroblasts undergoing replicative exhaustion in culture [2]. It has been shown that senescence can be triggered in different cell types in response to diverse forms of cellular damage or stress (for review see [1]). Importantly, while senescence was denounced as a tissue culture phenomenon for many years, recent in vivo studies demonstrated that cellular senescence represents a potent failsafe mechanism against tumorigenesis and contributes to the cytotoxicity of certain anticancer agents (see for example [3-7]). Interestingly, senescent cells have also been observed in certain aged or damaged tissues and there is growing evidence that senescence checkpoints can affect the regenerative reserve of tissues and organismal aging [8-11]. However, senescence may also have positive effects on organ maintenance by limiting pathological responses to acute forms of injury such as fibrotic scarring in response to chemical induced liver injury [12].     Over the past years it was also shown that senescent cells can communicate with their environment by secreting a myriad of cytokines and growth factors. Interestingly, this "senescence associated secretory phenotype (SASP)" seems to be a double edged sword regarding tumor initiation and maintenance:    i)    On the one hand, it has been shown that the SASP can have pro-tumorigenic effects. In an experimental system it was shown that senescent mesenchymal cells can enhance the tumorigenicity of surrounding breast cancer cells [13].     ii)    Similarly, it is possible that the SASP enhances selection of transformed cell clones in aged organ systems. It has been shown that loss of proliferative competition of non-transformed cells can accelerate leukemogenesis [14]. It remains to be seen whether aberrant secretion of cytokines and growth factors by the SASP can accelerated this process in aged and chronically damage organ systems.     iii)    In contrast to its pro-tumorigenic aspect, the SASP could also have anti-tumor effects. A recent study showed that in a mosaic liver cancer mouse model the activation of p53 induced senescence, an upregulation of inflammatory cytokines, and activation of innate immune responses leading to tumour cell clearance [15].     iv)    In further support that the SASP could have anti-tumor activities, a series of recent papers showed that components of the SASP can stabilize the senescence cell cycle arrest via an autoregulatory feedback loop [16,17] or induces apoptosis of tumor cells [18].     In addition to its effects on tumorigenesis, the SASP could also influence tissue aging. Studies on aging telomere dysfunctional mice have provided direct experimental evidence for an in vivo activation of the SASP in response to telomere dysfunction [19]. Interestingly, this in vivo SASP provoked alterations in stem cell differentiation (skewing of hematopoiesis towards reduction in lymphopoiesis and enhancement of myelopoiesis) that are also characteristic signs of human aging.         Figure 1.     Different cellular stresses can induce senescence including telomere shortening, DNA damage, and oncogene activation. Senescence of tumor cells ...         In light of the many possible roles o the SASP in aging and carcinogenesis, it appears to be of utmost importance to decipher regulatory pathways controlling the SASP. In a current publication, Bhaumik et al. have identified 2 microRNAs (miR-146a/b) that negatively regulate the secretion of IL-6 and IL-8 - two of the SASP [20]. The authors show that these microRNAs are up-regulated at late stages of senescence, many days after a permanent cell cycle arrest has been established. Interestingly, the inhibitory miRs are most strongly up-regulated in senescence of cell lines that show a strong SASP but not in cell lines characterized by a weak SASP. The authors propose a new concept indicating that miRs 146a and b function in a negative feedback loop preventing an over-activation of the SASP in senescent cells. The authors present some initial data suggesting that activation of this negative feedback loop involves IL-1 receptor, IRAK-1, and NFκB signalling leading to an up-regulation of miRs-146a and b. A direct proof that this proposed feedback loop suppresses over-activation of the SASP remains to be demonstrated in future studies. The authors show that blockage of IL-1-receptor signalling prevents both the up-regulation of miRs-146a and b as well as Il-6 secretion. To confirm their new concept, it would be important to show that a selective blockage of miRs-146a and b results in over-activation of the SASP.     The work by Bhaumik et al. places mir-146a/b as central players to control IL-6 and IL-8 expression within the SASP. MicroRNAs are emerging therapeutic targets because their expression levels can be effectively modulated via the use of antagomirs (see for example [21]). Also, for increasing microRNA expression, microRNAs can be delivered into cellsin vivo (see for example [22]). Therefore, it will be interesting to functionally test the impact of mir-146 inhibition on tumorigenesis and aging in relevant mouse models. Such studies will be of particular interest, as recent work showed that IL-6 secretion by senescent cells is relevant for initiating and maintaining the senescene response via an autocrine loop [17]. A reduction of miR-146 could increase IL-6 levels in senescent cells, which should stabilize the senescence program and reduce the risk of malignant transformation. Furthermore, it can be speculated that reduction of mir-146 a/b will increase NfκB activation via IRAK1. As NfκB is modulating the expression of various inflammation associated genes, this may also lead to increased clearance of senescent tumor cells by the innate immune system. However, it should be mentioned that Il-6 secreted by senescent cells can also act as a mitogen for surrounding cells, thus potentially increasing the risk of malignant transformation [13,17]. Besides its function in SASP modulation, miR-146 was also reported to target the mRNAs of the BRCA1 and BRCA2 tumor suppressors. In a recent study a G to C polymorphism in miR-146, which leads to an increased processing and release of the mature microRNA, can predict an early onset of breast cancer [23].     Taken together, the study of Bhaumik et al. opens an interesting new research area dealing with the gene regulatory mechanisms that control activation of the SASP. Given the diverse roles of the SASP in modulating tumor progression, immune surveillance of damaged cells, and the stabilization of the senescence arrest itself, it will be of great interest to analyse the influence of SASP regulatory pathways during aging and cancer.

title: A minimal Tat system from a gram-positive organism: a bifunctional TatA subunit participates in discrete TatAC and TatA complexes.

text: The Tat system transports folded proteins across bacterial and thylakoid membranes. In Gram-negative organisms, a TatABC substrate-binding complex and separate TatA complex are believed to coalesce to form an active translocon, with all three subunits essential for translocation. Most Gram-positive organisms lack a tatB gene, indicating major differences in organization and possible differences in mode of action. Here, we have studied Tat complexes encoded by the tatAdCd genes of Bacillus subtilis. Expression of tatAdCd in an Escherichia coli tat null mutant results in efficient export of a large, cofactor-containing E. coli Tat substrate, TorA. We show that the tatAd gene complements E. coli mutants lacking either tatAE or tatB, indicating a bifunctional role for this subunit in B. subtilis. Second, we have identified and characterized two distinct Tat complexes that are novel in key respects: a TatAdCd complex of approximately 230 kDa that is significantly smaller than the analogous E. coli TatABC complex (approximately 370 kDa on BN gels) and a separate TatAd complex. The latter is a discrete entity of approximately 270 kDa as judged by gel filtration chromatography, very different from the highly heterogeneous E. coli TatA complex that ranges in size from approximately 50 kDa to over 600 kDa. TatA heterogeneity has been linked to the varying size of Tat substrates being translocated, but the singular nature of the B. subtilis TatAd complex suggests that discrete TatAC and TatA complexes may form a single form of translocon.

title: The novel immunosuppressive enzyme IL4I1 is expressed by neoplastic cells of several B-cell lymphomas and by tumor-associated macrophages

text: We previously reported a strong IL4I1 gene expression in primary mediastinal B-cell lymphoma (PMBL) and recently identified the protein as a secreted L-phenylalanine oxidase, physiologically expressed by myeloid cells, which inhibits T-cell proliferation in vitro. Here, we analyzed the pattern of IL4I1 protein expression in 315 human lymphoid and non-lymphoid malignancies. Besides PMBL, IL4I1 expression in tumors was very frequent. IL4I1 was detected in tumor-associated macrophages from most of the tumors and in neoplastic cells from follicular lymphoma, classic and nodular lymphocyte predominant Hodgkin lymphomas and small lymphocytic lymphoma, three of which are germinal center derived. IL4I1-positive tumor cells were also detected in rare cases of solid cancers, mainly mesothelioma. The enzymatic activity paralleled protein expression, suggesting that IL4I1 is functional in vivo. Depending on the tumor type, IL4I1 may impact on different infiltrating lymphocyte populations with consequences on tumor evolution. In the particular case of follicular lymphoma cells, which are susceptible to antitumor cytotoxic T cells killing but depend on interactions with local T helper cells for survival, a high level of IL4I1 expression seems associated with the absence of bone marrow involvement and a better outcome. These findings plead for an evaluation of IL4I1 as a prognosis factor.


query: Venules have less significant tunica adventitia than arterioles.

title: Scaffold-based three-dimensional human fibroblast culture provides a structural matrix that supports angiogenesis in infarcted heart tissue.

text:
BACKGROUND We have developed techniques to implant angiogenic patches onto the epicardium over regions of infarcted cardiac tissue to stimulate revascularization of the damaged tissue. These experiments used a scaffold-based 3D human dermal fibroblast culture (3DFC) as an epicardial patch. The 3DFC contains viable cells that secrete angiogenic growth factors and has previously been shown to stimulate angiogenic activity. The hypothesis tested was that a viable 3DFC cardiac patch would stimulate an angiogenic response within an area of infarcted cardiac tissue.
 METHODS AND RESULTS A coronary occlusion of a branch of the left anterior descending coronary artery was performed by thermal ligation in severe combined immunodeficient mice. 3DFCs with or without viable cells were sized to the damaged area, implanted in replicate mice onto the epicardium at the site of tissue injury, and compared with animals that received infarct surgery but no implant. Fourteen and 30 days after surgery, hearts were exposed and photographed, and tissue samples were prepared for histology and cytochemistry. Fourteen and 30 days after surgery, the damaged myocardium receiving viable 3DFC exhibited a significantly greater angiogenic response (including arterioles, venules, and capillaries) than nonviable and untreated control groups.
 CONCLUSIONS In this animal model, viable 3DFC stimulates angiogenesis within a region of cardiac infarction and can augment a repair response in damaged tissue. Therefore, a potential use for 3DFC is the repair of myocardial tissue damaged by infarction.

title: Endothelium-mediated relaxation of porcine collateral-dependent arterioles is improved by exercise training.

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BACKGROUND Endothelium-dependent modulation of coronary tone is impaired in the collateral-dependent coronary microcirculation. We used a porcine model of chronic coronary occlusion and collateral development to evaluate the hypothesis that exercise training enhances endothelium-mediated relaxation and increases endothelial nitric oxide synthase (ecNOS) mRNA levels of collateral-dependent microvasculature.
 METHODS AND RESULTS Adult female miniature swine were subjected to chronic, progressive ameroid occlusion of the proximal left circumflex coronary artery (LCx); after 2 months, animals were randomly exposed to 16-week exercise-training (EX group; treadmill running) or sedentary (SED group; cage confinement) protocols. After completion of EX or SED programs, coronary arterioles ( approximately 100 microm in diameter) were isolated from collateral-dependent LCx (distal to occlusion) and nonoccluded left anterior descending coronary artery (LAD) regions of each heart. Arterioles were studied by in vitro videomicroscopy or frozen for ecNOS mRNA analysis (RT-PCR techniques). Relaxation to the endothelium-dependent vasodilator bradykinin was decreased (P<0.05) in arterioles isolated from collateral-dependent LCx versus nonoccluded LAD regions of SED animals. Bradykinin-mediated relaxation, however, was not different in LCx versus LAD arterioles isolated from EX animals. Nitroprusside-induced relaxation was unaffected by either chronic occlusion or exercise. Importantly, ecNOS mRNA expression was significantly decreased in arterioles isolated from LCx versus LAD regions of SED animals. After training, ecNOS mRNA expression was not different between LAD and LCx arterioles.
 CONCLUSIONS These data indicate that exercise training enhances bradykinin-mediated relaxation of collateral-dependent LCx arterioles isolated after chronic coronary occlusion, most likely because of effects on ecNOS mRNA expression and increased production of NO.

title: Smooth muscle lineage diversity in the chick embryo. Two types of aortic smooth muscle cell differ in growth and receptor-mediated transcriptional responses to transforming growth factor-beta.

text: Lineage analysis studies in the avian embryo have identified two types of smooth muscle cells (SMCs) in the tunica media of large elastic arteries; one that originates within the cardiac neural crest and is ectoderm in origin (Ect) and another that arises from local mesenchyme of mesodermal origin (Mes). To determine if differences in primary embryonic lineage can give rise to SMCs with stable differences in growth and differentiation properties, we isolated Ect and Mes SMCs from the Day 14 chick embryo aorta. We report that despite different primary embryonic origins, Ect and Mes SMCs express nearly identical levels of seven SMC differentiation markers in vitro, consistent with their common smooth muscle developmental fates in vivo. By contrast, Ect SMCs displayed a greater capacity for growth in serum-free medium than Mes SMCs, but only under conditions permitting short-range cell-cell interactions. Most of the peptide growth factors tested that might account for serum-independent growth (PDGF-AA, PDGF-BB, basic FGF, EGF, or activin) stimulated DNA synthesis to similar extents in Ect and Mes SMCs. However, we found dramatic, lineage-dependent differences in SMC responses to transforming growth factor-beta (TGF-beta). Exposure to TGF-beta 1 (0.4 to 400 pmole/liter) consistently increased DNA synthesis in Ect SMCs, whereas in paired cultures of Mes SMCs, TGF-beta 1 was growth inhibitory. In SMC cultures transfected with p3TP-lux, a luciferase reporter controlled by the TGF-beta 1-response elements of the human PAI-1 promoter, TGF-beta 1 (120 pM) produced 12 +/- 2-fold increases in luciferase activity in Ect SMCs and only 3 +/- 1.5-fold increases in Mes SMCs. Analysis of TGF-beta receptor phenotypes by Northern blot, radioligand binding, and crosslinking assays showed that Ect and Mes SMCs expressed similar levels of types I, II, and III TGF-beta receptors. However, using a polyclonal antibody specific for the chick type II TGF-beta receptor subunit, we demonstrate that Mes SMCs produce a fully glycosylated form of this protein while Ect SMCs elaborate only an unglycosylated type II TGF-beta receptor. These results show that Ect and Mes SMCs exhibit lineage-dependent differences in growth and receptor-mediated transcriptional responses to at least one important class of SMC morphogens and growth modifiers, e.g., the TGF-betas. Our findings suggest that different SMC populations within a common vessel wall may respond in lineage-dependent ways to signals that direct formation of the tunica media in the embryo and to factors involved in the progression of vascular disease later in life.

title: Arteriolar function in visceral adipose tissue is impaired in human obesity.

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OBJECTIVE The purpose of this study was to characterize the relationship between adipose tissue phenotype and depot-specific microvascular function in fat.
 METHODS AND RESULTS In 30 obese subjects (age 42±11 years, body mass index 46±11 kg/m(2)) undergoing bariatric surgery, we intraoperatively collected visceral and subcutaneous adipose tissue and characterized depot-specific adipose phenotypes. We assessed vasomotor function of the adipose microvasculature using videomicroscopy of small arterioles (75-250 μm) isolated from different fat compartments. Endothelium-dependent, acetylcholine-mediated vasodilation was severely impaired in visceral arterioles, compared to the subcutaneous depot (P<0.001 by ANOVA). Nonendothelium dependent responses to papaverine and nitroprusside were similar. Endothelial nitric oxide synthase inhibition with N(ω)-nitro-l-arginine methyl ester reduced subcutaneous vasodilation but had no effect on severely blunted visceral arteriolar responses. Visceral fat exhibited greater expression of proinflammatory, oxidative stress-related, hypoxia-induced, and proangiogenic genes; increased activated macrophage populations; and had a higher capacity for cytokine production ex vivo.
 CONCLUSIONS Our findings provide clinical evidence that the visceral microenvironment may be intrinsically toxic to arterial health providing a potential mechanism by which visceral adiposity burden is linked to atherosclerotic vascular disease. Our findings also support the evolving concept that both adipose tissue quality and quantity may play significant roles in shaping cardiovascular phenotypes in human obesity.

title: Role of soluble guanylate cyclase in dilator responses of the cerebral microcirculation.

text: Responses of cerebral blood vessels to nitric oxide (NO) are mediated by soluble guanylate cyclase (sGC)-dependent and potentially by sGC-independent mechanisms. One sGC-independent mechanism by which NO may produce vasodilatation is inhibition of formation of a vasoconstrictor metabolite produced through the cytochrome P450 pathway. In these experiments, we examined the hypothesis that dilatation of cerebral microvessels in response to NO is dependent on activation of sGC. Diameters of cerebral arterioles (baseline diameter=94+/-5 micrometers, mean+/-S.E.) were measured using a closed cranial window in anesthetized rabbits. Under control conditions, YC-1 [3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole], an NO-independent activator of sGC, produced vasodilation that was blocked by ODQ (1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one)(10 microM), an inhibitor of sGC. These findings indicate that sGC is functionally important in cerebral arterioles. In addition, acetylcholine (which stimulates endogenous production of NO by endothelium) produced dilatation of cerebral arterioles that was inhibited by ODQ. For example, 1 microM acetylcholine dilated cerebral arterioles by 34+/-7 and 5+/-1% in the absence and presence of ODQ (10 microM), respectively. Increases in arteriolar diameter in response to sodium nitroprusside (1 microM, an NO donor) were inhibited by approximately 80% by ODQ, but were not affected by 17-ODYA (10 microM) or clotrimazole (10 microM), inhibitors of the cytochrome P450 pathway. Thus, dilatation of the cerebral microcirculation in response to exogenously applied and endogenously produced NO is dependent, in large part, on activation of sGC.

title: Pulmonary vascular lesions in end-stage idiopathic pulmonary fibrosis: Histopathologic study on lung explant specimens and correlations with pulmonary hemodynamics.

text: In patients presenting with idiopathic pulmonary fibrosis (IPF), modifications of pulmonary vessels are well defined in fibrotic areas but have not been accurately assessed in the intervening patches of preserved lung. Moreover, the relation between pulmonary vessel lesions and pulmonary hemodynamics is not well known. We therefore designed a retrospective study on lung explant specimens from 26 patients with a firm diagnosis of IPF who had undergone lung transplantation. Our aim was to (1) describe the vascular lesions, especially in preserved lung areas, and (2) correlate them with pulmonary hemodynamics. In dense fibrotic zones, thickening of the arterial and venous wall with severe luminal narrowing was present in each patient. In architecturally preserved lung zones, occlusion of venules and small pulmonary veins was observed in 65% of the patients, although there were only mild changes of muscular pulmonary arteries. We found a significant positive correlation between the macroscopic extent of lung fibrosis and mean pulmonary artery pressure, but we failed to find a relation between mean pulmonary artery pressure and venous/venular lesions in nonfibrotic areas. Our study points out that in many patients with IPF, nonfibrotic lung areas demonstrate an occlusive venopathy, the signification of which remains undetermined.

title: Sex-related differences in the presentation, treatment and outcomes among patients with acute coronary syndromes: the Global Registry of Acute Coronary Events.

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OBJECTIVE To assess whether sex differences exist in the angiographic severity, management and outcomes of acute coronary syndromes (ACS).
 METHODS The study comprised 7638 women and 19 117 men with ACS who underwent coronary angiography and were included in GRACE (Global Registry of Acute Coronary Events) from 1999-2006. Normal vessels/mild disease was defined as <50% stenosis in all epicardial vessels; advanced disease was defined as >or=one vessel with >or=50% stenosis.
 RESULTS Women were older than men and had higher rates of cardiovascular risk factors. Men and women presented equally with chest pain; however, jaw pain and nausea were more frequent among women. Women were more likely to have normal/mild disease (12% vs 6%, p<0.001) and less likely to have left-main and three-vessel disease (27% vs 32%, p<0.001) or undergo percutaneous coronary intervention (65% vs 68%, p<0.001). Women and men with normal and mild disease were treated less aggressively than those with advanced disease. Women with advanced disease had a higher risk of death (4% vs 3%, p<0.01). After adjustment for age and extent of disease, women were more likely to have adverse outcomes (death, myocardial infarction, stroke and rehospitalisation) at six months compared to men (odds ratio 1.24, 95% confidence interval 1.14 to 1.34); however, sex differences in mortality were no longer statistically significant.
 CONCLUSIONS Women with ACS were more likely to have cardiovascular disease risk factors and atypical symptoms such as nausea compared with men, but were more likely to have normal/mild angiographic coronary artery disease. Further study regarding sex differences related to disease severity is warranted.

title: Metagenomic analysis of microbial consortium from natural crude oil that seeps into the marine ecosystem offshore Southern California

text: Crude oils can be major contaminants of the marine ecosystem and microorganisms play a significant role in the degradation of its main constituents. To increase our understanding of the microbial hydrocarbon degradation process in the marine ecosystem, we collected crude oil from an active seep area located in the Santa Barbara Channel (SBC) and generated a total of about 52 Gb of raw metagenomic sequence data. The assembled data comprised ~500 Mb, representing ~1.1 million genes derived primarily from chemolithoautotrophic bacteria. Members of Oceanospirillales, a bacterial order belonging to the Deltaproteobacteria, recruited less than 2% of the assembled genes within the SBC metagenome. In contrast, the microbial community associated with the oil plume that developed in the aftermath of the Deepwater Horizon (DWH) blowout in 2010, was dominated by Oceanospirillales, which comprised more than 60% of the metagenomic data generated from the DWH oil plume. This suggests that Oceanospirillales might play a less significant role in the microbially mediated hydrocarbon conversion within the SBC seep oil compared to the DWH plume oil. We hypothesize that this difference results from the SBC oil seep being mostly anaerobic, while the DWH oil plume is aerobic. Within the Archaea, the phylum Euryarchaeota, recruited more than 95% of the assembled archaeal sequences from the SBC oil seep metagenome, with more than 50% of the sequences assigned to members of the orders Methanomicrobiales and Methanosarcinales. These orders contain organisms capable of anaerobic methanogenesis and methane oxidation (AOM) and we hypothesize that these orders - and their metabolic capabilities - may be fundamental to the ecology of the SBC oil seep.

title: Bile acid receptor TGR5 agonism induces NO production and reduces monocyte adhesion in vascular endothelial cells.

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OBJECTIVE TGR5 is a G-protein-coupled receptor for bile acids. So far, little is known about the function of TGR5 in vascular endothelial cells.    APPROACH AND RESULTS In bovine aortic endothelial cells, treatment with a bile acid having a high affinity to TGR5, taurolithocholic acid (TLCA), significantly increased NO production. This effect was abolished by small interfering RNA-mediated depletion of TGR5. TLCA-induced NO production was also observed in human umbilical vein endothelial cells measured via intracellular cGMP accumulation. TLCA increased endothelial NO synthase(ser1177) phosphorylation in human umbilical vein endothelial cells. This response was accompanied by increased Akt(ser473) phosphorylation and intracellular Ca(2+). Inhibition of these signals significantly decreased TLCA-induced NO production. We next examined whether TGR5-mediated NO production affects inflammatory responses of endothelial cells. In human umbilical vein endothelial cells, TLCA significantly reduced tumor necrosis factor-α-induced adhesion of monocytes, vascular cell adhesion molecule-1 expression, and activation of nuclear factor-κB. TLCA also inhibited lipopolysaccharide-induced monocyte adhesion to mesenteric venules in vivo. These inhibitory effects of TLCA were abrogated by NO synthase inhibition.
 CONCLUSIONS TGR5 agonism induces NO production via Akt activation and intracellular Ca(2+) increase in vascular endothelial cells, and this function inhibits monocyte adhesion in response to inflammatory stimuli.

title: Bone disease in pediatric patients undergoing dialysis with CAPD or CCPD.

text: The histologic features of renal osteodystrophy and the prevalence of bone aluminum deposition in children receiving regular dialysis have not been described. Forty-four pediatric patients undergoing continuous ambulatory (CAPD) or cycling (CCPD) peritoneal dialysis had bone biopsies and deferoxamine (DFO) infusion tests; all were receiving oral calcitriol. Osteitis fibrosa (OF) was found in 39%, mild lesions (M) in 25%, normal histology (NH) in 16%, aplastic lesions (AP) in 11%, and osteomalacia (OM) in 9%. Bone surface aluminum (SA) was present by histochemical staining in 10 out of 20 given aluminum-containing phosphate-binding agents and in 0 of 24 treated with calcium carbonate; chi 2 = 15.5, P less than 0.0001. Serum biochemistries and DFO infusion tests failed to predict bone histology, but plasma aluminum levels were markedly elevated and bone aluminum content was highest in patients with OM. Bone formation rate (BFR) correlated with serum parathyroid hormone (PTH), r = 0.55, P less than 0.001; BFR was inversely related to bone aluminum content (r = -0.42, P less than 0.01), even in patients with OF (r = -0.66, P less than 0.05). All patients with SA greater than 30% had normal or reduced BFR when compared to those with SA less than 30%; chi 2 = 12.2, P less than 0.005. Based on SA greater than 30%, six patients were classified as aluminum-related bone disease: three OM, one AP, and two NH. Two-thirds of pediatric patients undergoing CAPD/CCPD have persistent hyperparathyroidism despite treatment with calcitriol, but aluminum can adversely affect BFR when SA exceeds 30% regardless of histologic lesion or serum PTH level.

title: Influence of smoking and plasma factors on patency of femoropopliteal vein grafts.

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OBJECTIVE To determine the effects of smoking, plasma lipids, lipoproteins, apolipoproteins, and fibrinogen on the patency of saphenous vein femoropopliteal bypass grafts at one year.
 DESIGN Prospective study of patients with saphenous vein femoropopliteal bypass grafts entered into a multicentre trial.
 SETTING Surgical wards, outpatient clinics, and home visits coordinated by two tertiary referral centres in London and Birmingham.
 PATIENTS 157 Patients (mean age 66.6 (SD 8.2) years), 113 with patent grafts and 44 with occluded grafts one year after bypass.
 MAIN OUTCOME MEASURE Cumulative percentage patency at one year.
 RESULTS Markers for smoking (blood carboxyhaemoglobin concentration (p less than 0.05) and plasma thiocyanate concentration (p less than 0.01) and plasma concentrations of fibrinogen (p less than 0.001) and apolipoproteins AI (p less than 0.04) and (a) (p less than 0.05) were significantly higher in patients with occluded grafts. Serum cholesterol concentrations were significantly higher in patients with grafts that remained patent one year after bypass (p less than 0.005). Analysis of the smoking markers indicated that a quarter of patients (40) were untruthful in their claims to have stopped smoking. Based on smoking markers, patency of grafts in smokers was significantly lower at one year by life table analysis than in non-smokers (63% v 84%, p less than 0.02). Patency was significantly higher by life table analysis in patients with a plasma fibrinogen concentration below the median than in those with a concentration above (90% v 57%, p less than 0.0002). Surprisingly, increased plasma low density lipoprotein cholesterol concentration was significantly associated with improved patency at one year (85%) at values above the median compared with patency (only 68%) at values in the lower half of the range (p less than 0.02).
 CONCLUSIONS Plasma fibrinogen concentration was the most important variable predicting graft occlusion, followed by smoking markers. A more forceful approach is needed to stop patients smoking; therapeutic measures to improve patency of vein grafts should focus on decreasing plasma fibrinogen concentration rather than serum cholesterol concentration.

title: Effect of osteoporosis treatments on risk of non-vertebral fractures: review and meta-analysis of intention-to-treat studies

text: Most osteoporosis treatments have proven efficacy in reducing the risk of vertebral fractures, whereas evidence is less straightforward for prevention of non-vertebral fractures. Conclusions as to the efficacy of a treatment should be based primarily on analyses of the intention to treat (ITT) population rather than on exploratory subgroup analyses; however, non-vertebral anti-fracture efficacy has been largely derived by post-hoc subgroup analyses. This review and meta-analysis was performed to assess non-vertebral anti-fracture efficacy of several osteoporosis therapies, including a more stringent assessment of the ITT populations. Data on non-vertebral anti-fracture efficacy, a defined endpoint of the ITT analyses and confirmed by radiographs, were obtained from randomized, placebo-controlled, phase III clinical trials of at least 3-year duration. Meta-analyses were performed for the two bisphosphonates, alendronate and risedronate. Relative risks (RR), 95% confidence intervals (CI) and statistical significance for active treatment compared with placebo were calculated. Eleven clinical trials met the criteria for review, three of which showed statistically significant ( P ≤0.05) non-vertebral anti-fracture efficacy in the ITT population: two trials with risedronate and one trial with strontium. A meta-analysis showed significant reductions in the relative risk of non-vertebral fracture for both alendronate (RR=0.86; 95% CI: 0.76–0.97, P =0.012) and risedronate (RR=0.81; 95% CI: 0.71–0.92, P =0.001). Risedronate and strontium ranelate were the only treatments to show non-vertebral anti-fracture efficacy in this robust assessment of anti-fracture efficacy of osteoporosis therapy using ITT populations in trials of 3 years or more in duration. Risedronate was the only agent shown to demonstrate efficacy in more than one trial. Meta-analysis showed that both alendronate and risedronate provide non-vertebral anti-fracture efficacy.

title: Breast cancer clusters in the northeast United States: a geographic analysis.

text: High breast cancer mortality rates have been reported in the northeastern part of the United States, with recent attention focused on Long Island, New York. In this study, the authors investigate whether the high breast cancer mortality is evenly spread over the Northeast, in the sense that any observed clusters of deaths can be explained by chance alone, or whether there are clusters of statistical significance. Demographic data and age-specific breast cancer mortality rates for women were obtained for all 244 counties in 11 northeastern states and for the District of Columbia for 1988-1992. A recently developed spatial scan statistic is used, which searches for clusters of cases without specifying their size or location ahead of time, and which tests for their statistical significance while adjusting for the multiple testing inherent in such a procedure. The basic analysis is adjusted for age, with further analyses examining how the results are affected by incorporating race, urbanicity, and parity as confounding variables. There is a statistically significant and geographically broad cluster of breast cancer deaths in the New York City-Philadelphia, Pennsylvania, metropolitan area (p = 0.0001), which has a 7.4% higher mortality rate than the rest of the Northeast. The cluster remains significant when race, urbanicity, and/or parity are included as confounding variables. Four smaller subclusters within this area are also significant on their own strength: Philadelphia with suburbs (p = 0.0001), Long Island (p = 0.0001), central New Jersey (p = 0.0001), and northeastern New Jersey (p = 0.0001). The elevated breast cancer mortality on Long Island might be viewed less as a unique local phenomenon and more as part of a more general situation involving large parts of the New York City-Philadelphia metropolitan area. The several known and hypothesized risk factors for which we could not adjust and that may explain the detected cluster are most notably age at first birth, age at menarche, age at menopause, breastfeeding, genetic mutations, and environmental factors.

title: New development of the yolk sac theory in diabetic embryopathy: molecular mechanism and link to structural birth defects.

text: Maternal diabetes mellitus is a significant risk factor for structural birth defects, including congenital heart defects and neural tube defects. With the rising prevalence of type 2 diabetes mellitus and obesity in women of childbearing age, diabetes mellitus-induced birth defects have become an increasingly significant public health problem. Maternal diabetes mellitus in vivo and high glucose in vitro induce yolk sac injuries by damaging the morphologic condition of cells and altering the dynamics of organelles. The yolk sac vascular system is the first system to develop during embryogenesis; therefore, it is the most sensitive to hyperglycemia. The consequences of yolk sac injuries include impairment of nutrient transportation because of vasculopathy. Although the functional relationship between yolk sac vasculopathy and structural birth defects has not yet been established, a recent study reveals that the quality of yolk sac vasculature is related inversely to embryonic malformation rates. Studies in animal models have uncovered key molecular intermediates of diabetic yolk sac vasculopathy, which include hypoxia-inducible factor-1α, apoptosis signal-regulating kinase 1, and its inhibitor thioredoxin-1, c-Jun-N-terminal kinases, nitric oxide, and nitric oxide synthase. Yolk sac vasculopathy is also associated with abnormalities in arachidonic acid and myo-inositol. Dietary supplementation with fatty acids that restore lipid levels in the yolk sac lead to a reduction in diabetes mellitus-induced malformations. Although the role of the human yolk in embryogenesis is less extensive than in rodents, nevertheless, human embryonic vasculogenesis is affected negatively by maternal diabetes mellitus. Mechanistic studies have identified potential therapeutic targets for future intervention against yolk sac vasculopathy, birth defects, and other complications associated with diabetic pregnancies.

title: Relation of plasma leptin concentrations to sex, body fat, dietary intake, and peak oxygen uptake in young adult women and men.

text: The purpose of this study was to examine the relation of leptin to metabolic and dietary factors in college-age adults. Young adult women and men (n = 32) were recruited and underwent testing for measurement of body mass index, body composition, peak oxygen consumption (VO2peak), dietary intake, and plasma levels of leptin and insulin. Ln leptin was significantly greater for women than for men (2.1 versus 1.2 ng/mL, respectively). This difference remained significant even after adjusting ln leptin for fat mass and fat-free mass as covariates in separate analyses. VO2peak was higher for men than for women and this remained significant after adjustment for differences in fat-free mass and total body mass. Significant correlations were found between ln leptin and indicators of fat mass in women and men, with higher correlations for similar variables observed in men (r = 0.548, 0.674, and 0.732 for body mass index, percentage of body fat, and fat mass [kg] for women, respectively, and r = 0.740, 0.888, 0.858 for body mass index, percentage of body fat, and fat mass [kg] for men, respectively). Ln leptin showed a significant inverse relationship with VO2peak (r = -0.751) in men only. After adjusting ln leptin for body fat mass using partial correlations, ln leptin was not significantly associated with any of the measured variables. Alternatively, after normalization of ln leptin using fat mass as the divisor, a less adequate statistical analysis method, men showed statistical significant correlations between ln leptin and dietary intake and VO2peak. Although plasma leptin values were higher in women, stronger associations were evident for men than for women between leptin and metabolic and dietary factors.

title: Genome downsizing in polyploid plants

text: All else being equal, polyploids are expected to have larger C-values (amount of DNA in the unreplicated gametic nucleus) than their diploid progenitors, increasing in direct proportion with ploidy. This expectation is observed in some polyploid series, especially those newly formed, but there are examples suggesting that C-values in particular polyploids are less than expected. The availability of the Angiosperm DNA C-values database (http:// www.rbgkew.org.uk/cvavhomepage.html) has allowed this question to be addressed across a broad range of angiosperms and has revealed striking results deviating from expectation: (i) mean 1C DNA amount did not increase in direct proportion with ploidy, and (ii) mean DNA amount per basic genome (calculated by dividing the 2C value by ploidy) tended to decrease with increasing ploidy. These results suggest that loss of DNA following polyploid formation, or genome downsizing, may be a widespread phenomenon of considerable biological significance. Recent advances in our understanding of the molecular events that take place following polyploid formation together with new data on how DNA amounts can both increase and decrease provide some insights into how genome downsizing may take place. The nature of the evolutionary forces that may be driving DNA loss are also discussed.

title: Bullying in school: are short pupils at risk? Questionnaire study in a cohort.

text: Bullying is still prevalent in schools and is clearly stressful for victims. 1 2 It may also have undesirable consequences for bullies, with antisocial behaviour persisting into adulthood. Victims are generally reported to be weaker than the bullies. 2 3 This would suggest that very short pupils are more likely to be victims and less likely to be the aggressors. The Wessex growth study allowed us to examine the prevalence of bullying, as experienced or perpetrated by pupils of different heights.   Ninety two short normal adolescents who had been below the third centile for height at school entry4 and 117 controls matched for age and sex completed a bullying questionnaire, derived from work by Whitney and Smith.5 There were no refusals or any significant differences in sex or social class between the groups. Mean age (range) was 14.7 (13.4-15.7) years. Mean height SD scores were: short pupils −1.90 (−3.53 to −0.01), controls 0.31 (−1.41 …

title: National study of physician awareness and adherence to cardiovascular disease prevention guidelines.

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BACKGROUND Few data have evaluated physician adherence to cardiovascular disease (CVD) prevention guidelines according to physician specialty or patient characteristics, particularly gender.
 METHODS AND RESULTS An online study of 500 randomly selected physicians (300 primary care physicians, 100 obstetricians/gynecologists, and 100 cardiologists) used a standardized questionnaire to assess awareness of, adoption of, and barriers to national CVD prevention guidelines by specialty. An experimental case study design tested physician accuracy and determinants of CVD risk level assignment and application of guidelines among high-, intermediate-, or low-risk patients. Intermediate-risk women, as assessed by the Framingham risk score, were significantly more likely to be assigned to a lower-risk category by primary care physicians than men with identical risk profiles (P<0.0001), and trends were similar for obstetricians/gynecologists and cardiologists. Assignment of risk level significantly predicted recommendations for lifestyle and preventive pharmacotherapy. After adjustment for risk assignment, the impact of patient gender on preventive care was not significant except for less aspirin (P<0.01) and more weight management recommended (P<0.04) for intermediate-risk women. Physicians did not rate themselves as very effective in their ability to help patients prevent CVD. Fewer than 1 in 5 physicians knew that more women than men die each year from CVD.
 CONCLUSIONS Perception of risk was the primary factor associated with CVD preventive recommendations. Gender disparities in recommendations for preventive therapy were explained largely by the lower perceived risk despite similar calculated risk for women versus men. Educational interventions for physicians are needed to improve the quality of CVD preventive care and lower morbidity and mortality from CVD for men and women.

title: Costs of the COPD. Differences between intensive care unit and respiratory intermediate care unit.

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INTRODUCTION To assess whether respiratory intermediate care units (RICUs) are cost effective alternatives to intensive care units (ICUs) for patients with exacerbation of chronic obstructive pulmonary disease (COPD).
 PATIENTS AND METHODS Multi-centre, prospective, bottom-up cost study performed in 15 ICUs and 6 RICUs. COPD patients staying longer than 48 h were recruited; those coming from other ICUs/RICUs, with immune-deficiency or stroke, were excluded. After the ICU sample was standardised to the RICU distribution of the reason-for-admission and infusion of a vasoactive drug on admission, 60 ICU patients and 65 RICU patients remained, of the original 164 recruited. For each patient, besides clinical data on admission and discharge, daily information about the resources consumed were recorded and analysed in terms of their costs.
 RESULTS Total cost per patient was lower in RICUs than in ICUs (754 vs. 1507 Euro; P < 0.0001). In all items, except drugs and nutrition, we found a significant lower cost in RICUs. Dead patients were noticeably different in terms of disease severity between ICUs and RICUs, while surviving ones were not.
 CONCLUSIONS Our study suggests that some COPD patients, less severe and with pure respiratory failure, could be successfully and less costly treated in RICUs.

title: Integration of antiretroviral therapy with tuberculosis treatment.

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BACKGROUND We previously reported that integrating antiretroviral therapy (ART) with tuberculosis treatment reduces mortality. However, the timing for the initiation of ART during tuberculosis treatment remains unresolved.
 METHODS We conducted a three-group, open-label, randomized, controlled trial in South Africa involving 642 ambulatory patients, all with tuberculosis (confirmed by a positive sputum smear for acid-fast bacilli), human immunodeficiency virus infection, and a CD4+ T-cell count of less than 500 per cubic millimeter. Findings in the earlier-ART group (ART initiated within 4 weeks after the start of tuberculosis treatment, 214 patients) and later-ART group (ART initiated during the first 4 weeks of the continuation phase of tuberculosis treatment, 215 patients) are presented here.
 RESULTS At baseline, the median CD4+ T-cell count was 150 per cubic millimeter, and the median viral load was 161,000 copies per milliliter, with no significant differences between the two groups. The incidence rate of the acquired immunodeficiency syndrome (AIDS) or death was 6.9 cases per 100 person-years in the earlier-ART group (18 cases) as compared with 7.8 per 100 person-years in the later-ART group (19 cases) (incidence-rate ratio, 0.89; 95% confidence interval [CI], 0.44 to 1.79; P=0.73). However, among patients with CD4+ T-cell counts of less than 50 per cubic millimeter, the incidence rates of AIDS or death were 8.5 and 26.3 cases per 100 person-years, respectively (incidence-rate ratio, 0.32; 95% CI, 0.07 to 1.13; P=0.06). The incidence rates of the immune reconstitution inflammatory syndrome (IRIS) were 20.1 and 7.7 cases per 100 person-years, respectively (incidence-rate ratio, 2.62; 95% CI, 1.48 to 4.82; P<0.001). Adverse events requiring a switching of antiretroviral drugs occurred in 10 patients in the earlier-ART group and 1 patient in the later-ART group (P=0.006).
 CONCLUSIONS Early initiation of ART in patients with CD4+ T-cell counts of less than 50 per cubic millimeter increased AIDS-free survival. Deferral of the initiation of ART to the first 4 weeks of the continuation phase of tuberculosis therapy in those with higher CD4+ T-cell counts reduced the risks of IRIS and other adverse events related to ART without increasing the risk of AIDS or death. (Funded by the U.S. President's Emergency Plan for AIDS Relief and others; SAPIT ClinicalTrials.gov number, NCT00398996.).