bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo stimulation of apical P2 receptors in collecting ducts: evidence for inhibition of sodium reabsorption
Authors: Shirley D. G. , Bailey M. A. , Unwin R. J.
Published: February 2005

In vitro evidence suggests that intraluminal nucleotides, acting on apical P2 receptors, may influence amiloride-sensitive sodium reabsorption in collecting ducts. The present study has assessed this possibility directly in anesthetized rats, by determining the urinary recovery of22Na relative to that of [14C]inulin (Na/inulin recovery ratio) during in vivo microperfusion of late distal tubules with artificial tubular fluid containing various P2 agonists (all at 1 mM). In animals maintained on a control diet, in which amiloride-sensitive22Na reabsorption was modest, the poorly hydrolysable, broad-spectrum P2 agonist ATPγS had no significant effect on the Na/inulin recovery ratio. In contrast, in rats maintained on a low-sodium diet, in which amiloride-sensitive22Na reabsorption was considerably enhanced, ATPγS caused a significant increase in the Na/inulin recovery ratio (control: 14 ± 3%; ATPγS: 28 ± 4%; n = 32 pairs; P < 0.001, paired t-test). No change in the Na/inulin recovery ratio was seen in time controls (13 ± 3 vs. 14 ± 4%; n = 15 pairs). In subsequent experiments in rats maintained on a low-sodium diet, we used more selective agonists in an attempt to identify the receptor subtype responsible for the effect of ATPγS. The P2Y1agonist 2meSADP, the P2Y2/4agonists Ap4A and Cp4U, and the P2X agonist BzATP were all without significant effect on the Na/inulin recovery ratio. These findings constitute the first in vivo evidence for a functional role for apical P2 receptors in collecting ducts, but the identity of the receptor subtype(s) involved remains elusive.
Troglitazone's rapid and sustained activation of ERK1/2 induces cellular acidosis in LLC-PK1-F+cells: physiological responses
Authors: Oliver Robert , Friday Ellen , Turturro Francesco , Lacy Ashley , Welbourne Tomas
Published: February 2005

We studied the signal pathway through which troglitazone (TRO) acts in inducing cellular acidosis in LLC-PK1-F+cells in relation to ammoniagenesis and DNA synthesis. Cells were grown to confluent monolayers in 30-mm chambers and monitored for intracellular pH (pHi) by the BCECF assay and activated ERK by phospo-ERK1/2 antibodies. TRO induces a severe cellular acidosis (pHi6.68 ± 0.10 vs. 7.28 ± 0.07 time control at 4 min, P < 0.01), whereas phospho-ERK1/2 to total ERK1/2 ratio increases 3.4-fold ( P < 0.01). To determine whether ERK1/2 was activated by cellular acidosis or TRO was acting via MEK1/2 to activate ERK1/2, cells were pretreated with specific inhibitors of MEK1/2 activity, PD-098059 and U-0126, followed by the addition of TRO or vehicle. With MEK1/2 activity inhibited, TRO treatment failed to activate ERK1/2. Preventing ERK1/2 activation abrogated the TRO-induced cellular acidosis and maintained the pHiwithin the low normal range (7.06 ± 0.11). To determine whether blocking ERK activation prevents TRO's inhibitory effect on NHE activity, cells were acid-loaded and the recovery response was monitored as ΔpHi/ t over a 4-min recovery period. TRO inhibited NHE activity by 85% ( P < 0.01), whereas blocking ERK activation restored the response. We measured activated ERK levels and pHiafter 3- and 18-h exposure to TRO or extracellular acidosis (pHe = 6.95) to determine whether ERK activation was sustained. Whereas both TRO and extracellular acidosis increased activated ERK and decreased pHiafter 3 h, only TRO sustained this response at 18 h. Furthermore, both enhanced ammoniagenesis and decreased DNA synthesis reflected the effect of TRO to induce and sustain a cellular acidosis.
Altered expression of renal apical plasma membrane Na+transporters in the early phase of genetic hypertension
Authors: Capasso Giovambattista , Rizzo Maria , Evangelista Ciriana , Ferrari Patrizia , Geelen Ghislaine , Lang Florian , Bianchi Giuseppe
Published: February 2005

The present study explores whether the development of hypertension in the Milan strain of rats (MHS) rats is preceded or paralleled by alterations of mRNA and/or protein levels of the major luminal Na+transporters. MHS rats were studied at 23–25 days after birth; age-matched Milan normotensive (MNS) rats were used as controls. The glomerular filtration rate (GFR), measured by inulin clearance, was higher in MHS than in MNS rats, while the mean blood pressure was not different in the two strains of animals indicating that the MHS rats were still in the prehypertensive state. Type 3 sodium/hydrogen exchanger (NHE3), bumetanide-sensitive sodium-potassium-2 chloride cotransporter (NKCC2), sodium-chloride cotransporter (NCC) and α-ENaC mRNA abundances were quantified by competitive PCR. In MHS compared with MNS, mRNA abundance was unchanged for NHE3 in proximal tubules, higher for NKCC2 in medullary thick ascending limbs of Henle's loops (TAL) and lower for NCC in distal convoluted tubules (DCT) and for α-ENaC along collecting ducts (CD). Western blot experiments revealed 1) unchanged NHE3; 2) a significant increase in NKCC2 in the outer medulla; 3) a significant decrease in NCC in the renal cortex and of α-ENaC in both the renal cortex and outer medulla, whereas β- and γ-ENaC remained unchanged. These data indicate that, in MHS rats, there is a strong upregulation of NKCC2 along the TAL associated with increased GFR, robust inhibition of NCC cotransporter along the DCT and modest downregulation of α-ENaC along the CD. The interplay of the various Na+transporters may well explain why, at this age, the rats are still in the prehypertensive state.
Lack of On-Going Adaptations in the Soleus Muscle Activity During Walking in Patients Affected by Large-Fiber Neuropathy
Authors: Mazzaro Nazarena , Grey Michael J. , Sinkjær Thomas , Andersen Jacob Buus , Pareyson Davide , Schieppati Marco
Published: February 2005

The aim of this study was to investigate the contribution of feedback from large-diameter sensory fibers to the adaptation of soleus muscle activity after small ankle trajectory modifications during human walking. Small-amplitude and slow-velocity ankle dorsiflexion enhancements and reductions were applied during the stance phase of the gait cycle to mimic the normal variability of the ankle trajectory during walking. Patients with demyelination of large sensory fibers (Charcot-Marie-Tooth type 1A and antibodies to myelin-associated glycoprotein neuropathy) and age-matched controls participated in this study. The patients had absent light-touch sense in the toes and feet and absent quadriceps and Achilles tendon reflexes, indicating functional loss of large sensory fibers. Moreover, their soleus stretch reflex response consisted of a single electromyographic (EMG) burst with delayed onset and longer duration ( P < 0.01) than the short- and medium-latency reflex responses observed in healthy subjects. In healthy subjects, the soleus EMG gradually increased or decreased when the ankle dorsiflexion was, respectively, enhanced or reduced. In the patients, the soleus EMG increased during the dorsiflexion enhancements; however, the velocity sensitivity of this response was decreased compared with the healthy volunteers. When the dorsiflexion was reduced, the soleus EMG was unchanged. These results indicate that the enhancement of the soleus EMG is mainly sensitive to feedback from primary and secondary muscle spindle afferents and that the reduction may be mediated by feedback from the group Ib pathways. This study provides evidence for the role of sensory feedback in the continuous adaptation of the soleus activity during the stance phase of human walking.
Variants in the Wilms’ tumor gene are associated with focal segmental glomerulosclerosis in the African American population
Authors: Orloff Mohammed S. , Iyengar Sudha K. , Winkler Cheryl A. , Goddard Katrina A. B. , Dart Richard A. , Ahuja Tejinder S. , Mokrzycki Michele , Briggs William A. , Korbet Stephen M. , Kimmel Paul L. , Simon Eric E. , Trachtman Howard , Vlahov David , Michel Donna M. , Berns Jeffrey S. , Smith Michael C. , Schelling Jeffrey R. , Sedor John R. , Kopp Jeffrey B.
Published: February 2005

Wilms’ tumor gene ( WT1) is important for nephrogenesis and gonadal growth. WT1 mutations cause Denys-Drash and Frasier syndromes, which are characterized by glomerular scarring. To test whether genetic variations in WT1 and WIT1 (gene immediately 5′ to WT1) associate with focal segmental glomerulosclerosis (FSGS), patients with biopsy-proven idiopathic and HIV-1-associated FSGS were enrolled in a multicenter study. We genotyped SNP rs6508 located in WIT1 exon 1, three SNPs (rs2301250, rs2301252, rs2301254) in the promoter shared by WT1 and WIT1, rs2234590 in exon 6, rs2234591 in intron 6, rs16754 in exon 7, and rs1799937 in intron 9 of WT1. Cases ( n = 218) and controls ( n = 281) were compared in the African American population. Stratification by HIV-1 infection status showed that SNPs rs6508, rs2301254, and rs1799937 were significantly associated with FSGS [rs6508 odds ratio (OR) 1.82, P = 0.006; rs2301254 OR 1.65, P = 0.049; rs1799937 OR 1.91, P = 0.005] in the non-HIV-1 group and rs2234591 (OR 0.234, P = 0.011) in the HIV-1 group. Haplotype analyses in the population revealed that seven SNPs were associated with FSGS; five SNPs had the highest contingency score [−log10( P value) = 13.57] in the HIV-1 group. This association could not be explained by population substructure. We conclude that SNPs in WT1 and WIT1 genes are significantly associated with FSGS, suggesting that variants in these genes may mediate pathogenesis by altering WT1 function. Furthermore, HIV-1 infection status interacts with genetic variations in both genes to influence this phenotype. We speculate that nephropathy liability alleles in WT1 pathway genes cause podocyte dysfunction and glomerular scarring.
Genetic determinants of weight of fast- and slow-twitch skeletal muscle in 500-day-old mice of the C57BL/6J and DBA/2J lineage
Authors: Lionikas A. , Blizard D. A. , Gerhard G. S. , Vandenbergh D. J. , Stout J. T. , Vogler G. P. , McClearn G. E. , Larsson L.
Published: February 2005

C57BL/6J (B6) and DBA/2J (D2) strains and two derivative populations, BXD recombinant inbred strains (BXD RIs) and B6D2F2, were used to explore genetic basis for variation in muscle weight at 500 days of age. In parallel with findings in 200-day-old mice (Lionikas A, Blizard DA, Vandenbergh DJ, Glover MG, Stout JT, Vogler GP, McClearn GE, and Larsson L. Physiol Genomics 16: 141–152, 2003), weight of slow-twitch soleus, mixed gastrocnemius, and fast-twitch tibialis anterior (TA) and extensor digitorum longus (EDL) muscles was 13–22% greater ( P < 0.001) in B6 than in D2. Distribution of BXD RI strain means indicated that genetic influence on muscle weight (strain effect P < 0.001, all muscles) was of polygenic origin, and effect of genetic factors differed between males and females (strain-by-sex interaction: P < 0.01 for soleus, EDL; P < 0.05 for TA, gastrocnemius). Linkage analyses in B6D2F2population identified QTL affecting muscle weight on Chr 1, 2, 6, and 9. Pleiotropic influences were observed for QTL on Chr 1 (soleus, TA), 2 (TA, EDL, gastrocnemius), and 9 (soleus, TA, EDL) and were not related to muscle type (fast/slow-twitch) or function (flexor/extensor). Effect of QTL on Chr 9 on soleus muscle was male specific. QTL on Chr 2 and 6 were previously observed at 200 days of age, whereas QTL on Chr 1 and 9 are novel muscle weight QTL. In summary, muscle weight in B6/D2 lineage is affected by a polygenic system that has variable influences at different ages, between males and females, and across muscles in a manner independent of muscle type.
Role of Noninvasive Testing in the Clinical Evaluation of Women With Suspected Coronary Artery Disease
Authors: Mieres Jennifer H. , Shaw Leslee J. , Arai Andrew , Budoff Matthew J. , Flamm Scott D. , Hundley W. Gregory , Marwick Thomas H. , Mosca Lori , Patel Ayan R. , Quinones Miguel A. , Redberg Rita F. , Taubert Kathryn A. , Taylor Allen J. , Thomas Gregory S. , Wenger Nanette K.
Published: February 2005

Cardiovascular disease is the leading cause of mortality for women in the United States. Coronary heart disease, which includes coronary atherosclerotic disease, myocardial infarction, acute coronary syndromes, and angina, is the largest subset of this mortality, with >240 000 women dying annually from the disease. Atherosclerotic coronary artery disease (CAD) is the focus of this consensus statement. Research continues to report underrecognition and underdiagnosis of CAD as contributory to high mortality rates in women. Timely and accurate diagnosis can significantly reduce CAD mortality for women; indeed, once the diagnosis is made, it does appear that current treatments are equally effective at reducing risk in both women and men. As such, noninvasive diagnostic and prognostic testing offers the potential to identify women at increased CAD risk as the basis for instituting preventive and therapeutic interventions. Nevertheless, the recent evidence-based practice program report from the Agency for Healthcare Research and Quality noted the paucity of women enrolled in diagnostic research studies. Consequently, much of the evidence supporting contemporary recommendations for noninvasive diagnostic studies in women is extrapolated from studies conducted predominantly in cohorts of middle-aged men. The majority of diagnostic and prognostic evidence in cardiac imaging in women and men has been derived from observational registries and referral populations that are affected by selection and other biases. Thus, a better understanding of the potential impact of sex differences on noninvasive cardiac testing in women may greatly improve clinical decision making. This consensus statement provides a synopsis of available evidence on the role of the exercise ECG and cardiac imaging modalities, both those in common use as well as developing technologies that may add clinical value to the diagnosis and risk assessment of the symptomatic and asymptomatic woman with suspected CAD.
Percutaneous Coronary Intervention and Adjunctive Pharmacotherapy in Women
Authors: Lansky Alexandra J. , Hochman Judith S. , Ward Patricia A. , Mintz Gary S. , Fabunmi Rosalind , Berger Peter B. , New Gishel , Grines Cindy L. , Pietras Cody G. , Kern Morton J. , Ferrell Margaret , Leon Martin B. , Mehran Roxana , White Christopher , Mieres Jennifer H. , Moses Jeffrey W. , Stone Gregg W. , Jacobs Alice K.
Published: February 2005

More than 1.2 million percutaneous coronary interventions are performed annually in the United States, with only an estimated 33% performed in women, despite the established benefits of percutaneous coronary intervention and adjunctive pharmacotherapy in reducing fatal and nonfatal ischemic complications in acute myocardial infarction and high-risk acute coronary syndromes. This statement reviews sex-specific data on the safety and efficacy of contemporary interventional therapies in women.
Caring and Elementary Teaching
Authors: Hansen Paul , Mulholland Judith A.
Published: February 2005

This article reports findings from a research project on the early career path of a group of male elementary school teachers. Issues of caring for children and disparities between how male and female teachers are permitted to relate to their elementary-age students are explored. In the preservice situation, the participants experienced tensions between how they, as male teachers, would naturally be inclined to show care toward students and the limitations that they felt were imposed on them by societal concerns about issues of child protection. During their 1st year of teaching, some of these frustrations endured, but participants found different and more acceptable ways of showing care. These ways of showing care can be described as being located on a professional rather than a parental end of a continuum of caring.
Rethinking the “Gap”
Authors: Escamilla Kathy , Chávez Lorretta , Vigil Peter
Published: February 2005

This article challenges the pervasive notion that linguistic and ethnic diversity are causes of the perceived gap in achievement in schools highly affected by Spanish-speaking students participating in programs of bilingual education. The study examines existing data from the state of Colorado with regard to student achievement and compares these data to teacher and policy maker perceptions about Latino Spanish-speaking students and bilingual education programs. Results indicate that teachers and policy makers largely adhere to the notion that there is a gap in achievement between Spanish-speaking students and other Colorado students and that language in particular is a problem. Student-achievement data from the Colorado Student Assessment Program, however, indicate that Spanish speakers in English-language acquisition/bilingual classrooms are among the highest performing students in their schools. Furthermore, findings from this study challenge teacher educators and teachers to be more critical in interpreting the results from high-stakes tests.
Janusz Korczak
Authors: Efron Sara
Published: February 2005

For more than 30 years, Janusz Korczak (1878-1942) devoted his life to educating orphaned Jewish children, and he stayed with them to the end as they all perished in the Treblinka concentration camp. In his teaching and writing, Korczak encouraged teachers to become autonomous knowledge producers by questioning and interrogating their work. Korczak not only conceptualized this perception but also embodied it throughout hiswork as an educator. Hewas a pioneer in recognizing the contributions of teacher research to serving the students’interests and to the teacher’s ownsense of empowerment. He respected the capabilities of science and objective measurement but at the same time appreciated the uniqueness and mysterious nature of the human soul that requires subjective, context-related, and intuitive perspective. For Korczak, research was the practical tool that would allow practitionerresearchers to spread their wings and dream of possibilities.
PIG-A mutations in normal hematopoiesis
Authors: Hu Rong , Mukhina Galina L. , Piantadosi Steven , Barber Jamie P. , Jones Richard J. , Brodsky Robert A.
Published: February 2005

Paroxysmal nocturnal hemoglobinuria (PNH) is caused by phosphatidylinositol glycan–class A (PIG-A) mutations in hematopoietic stem cells (HSCs). PIG-A mutations have been found in granulocytes from most healthy individuals, suggesting that these spontaneous PIG-A mutations are important in the pathogenesis of PNH. It remains unclear if these PIG-A mutations have relevance to those found in PNH. We isolated CD34+ progenitors from 4 patients with PNH and 27 controls. The frequency of PIG-A mutant progenitors was determined by assaying for colony-forming cells (CFCs) in methylcellulose containing toxic doses of aerolysin (1 × 10-9 M). Glycosylphosphatidylinositol (GPI)–anchored proteins serve as receptors for aerolysin; thus, PNH cells are resistant to aerolysin. The frequency of aerolysin resistant CFC was 14.7 ± 4.0 × 10-6 in the bone marrow of healthy donors and was 57.0 ± 6.7 × 10-6 from mobilized peripheral blood. DNA was extracted from individual day-14 aerolysin-resistant CFCs and the PIG-A gene was sequenced to determine clonality. Aerolysin-resistant CFCs from patients with PNH exhibited clonal PIG-A mutations. In contrast, PIG-A mutations in the CFCs from controls were polyclonal, and did not involve T cells. Our data confirm the finding that PIG-A mutations are relatively common in normal hematopoiesis; however, the finding suggests that these mutations occur in differentiated progenitors rather than HSCs.
Regulation of CXCR3 and CXCR4 expression during terminal differentiation of memory B cells into plasma cells
Authors: Muehlinghaus Gwendolin , Cigliano Luisa , Huehn Stephan , Peddinghaus Anette , Leyendeckers Heike , Hauser Anja E. , Hiepe Falk , Radbruch Andreas , Arce Sergio , Manz Rudolf A.
Published: February 2005

C-X-C motif chemokine receptor 3 (CXCR3) and CXCR4 expressed on immunoglobulin G (IgG)–plasma-cell precursors formed in memory immune responses are crucial modulators of the homing of these cells. Here, we studied the regulation of the expression of these chemokine receptors during the differentiation of human memory B cells into plasma cells. We show that CXCR3 is absent on CD27- naive B cells but is expressed on a fraction of memory B cells, preferentially on those coexpressing IgG1. On differentiation into plasma-cell precursors, CXCR3+ memory B cells maintain the expression of this chemokine receptor. CXCR3- memory B cells up-regulate CXCR3 and migrate toward concentration gradients of its ligands only when costimulated with interferon γ (IFN-γ), but not interleukin 4 (IL-4), IL-1β, IL-6, IFN-α, IFN-β, or tumor necrosis factor α (TNF-α). In contrast, the differentiation of CXCR4- B cells into plasma cells is generally accompanied by the induction of CXCR4 expression. These results show that lack of CXCR4 expression on plasma-cell precursors is not a limiting factor for plasma-cell homing and that the expression of CXCR3 on memory B cells and plasma-cell precursors is induced by IFN-γ, provided in human T helper type 1 (Th1)–biased immune responses. Once induced in memory B cells, CXCR3 expression remains part of the individual cellular memory.
Small-molecule XIAP inhibitors derepress downstream effector caspases and induce apoptosis of acute myeloid leukemia cells
Authors: Carter Bing Z. , Gronda Marcela , Wang Zhiliang , Welsh Kate , Pinilla Clemencia , Andreeff Michael , Schober Wendy D. , Nefzi Adel , Pond Gregory R. , Mawji Imtiaz A. , Houghten Richard A. , Ostresh John , Brandwein Joseph , Minden Mark D. , Schuh Andre C. , Wells Richard A. , Messner Hans , Chun Kathy , Reed John C. , Schimmer Aaron D.
Published: February 2005

We tested the effects of small-molecule XIAP antagonists based on a polyphenylurea pharmacophore on cultured acute myelogenous leukemia (AML) cell lines and primary patient samples. X-linked inhibitor of apoptosis protein (XIAP) antagonist N-[(5R)-6-[(anilinocarbonyl)amino]-5-((anilinocarbonyl){[(2R)-1-(4-cyclohexylbutyl)pyrrolidin-2-yl]methyl}amino)hexyl]-N-methyl-N′-phenylurea (1396-12), but not a structurally related control compound, induced apoptosis of primary leukemia samples with a lethal dose (LD50) of less than 10 μM in 16 of 27 (60%) samples. In contrast, XIAP antagonist 1396-12 was not lethal to the normal hematopoietic cells in short-term cytotoxicity assays. Response of primary AML specimens to XIAP inhibitor correlated with XIAP protein levels, with higher levels of XIAP associated with sensitivity. The XIAP antagonist 1396-12 induced activation of downstream caspases 3 and 7 prior to the activation of upstream caspase 8 and caspase 9. Apoptosis induction was also independent of B-cell lymphoma protein-2 (Bcl-2) or caspase 8, indicative of a downstream effect on apoptotic pathways. Thus, polyphenylurea-based XIAP antagonsists directly induce apoptosis of leukemia cells and AML patient samples at low micromolar concentrations through a mechanism of action distinct from conventional chemotherapeutic agents.
Positive and negative regulation of c-Myb by cyclin D1, cyclin-dependent kinases, and p27 Kip1
Authors: Lei Wanli , Liu Fan , Ness Scott A.
Published: February 2005

The c-Myb transcription factor controls differentiation and proliferation in hematopoietic and other cell types and has latent transforming activity, but little is known about its regulation during the cell cycle. Here, c-Myb was identified as part of a protein complex from human T cells containing the cyclin-dependent kinase (CDK) CDK6. Assays using model reporter constructs as well as endogenous target genes showed that the activity of c-Myb was inhibited by cyclin D1 plus CDK4 or CDK6 but stimulated by expression of the CDK inhibitors p16 Ink4a, p21 Cip1, or p27 Kip1. Mapping experiments identified a highly conserved region in c-Myb which, when transferred to the related A-Myb transcription factor, also rendered it responsive to CDKs and p27. The results suggest that c-Myb activity is directly regulated by cyclin D1 and CDKs and imply that c-Myb activity is regulated during the cell cycle in hematopoietic cells.
The targeting of primary effusion lymphoma cells for apoptosis by inducing lytic replication of human herpesvirus 8 while blocking virus production
Authors: Klass Carmen M. , Krug Laurie T. , Pozharskaya Veronika P. , Offermann Margaret K.
Published: February 2005

Primary effusion lymphoma (PEL) is a B-cell lymphoma in which human herpesvirus-8 (HHV-8) is found within all tumor cells and represents a target for selectively destroying tumor cells. HHV-8 is latent in most PEL cells and, hence, resistant to antiviral agents that inhibit lytic replication. We demonstrate that PEL cell lines containing HHV-8 without and with coinfection with Epstein-Barr virus responded to the antiseizure medication valproate with entry into the lytic cascade and production of infectious virus. Minimal cell death occurred when noninfected BL-41 cells were incubated with valproate, whereas apoptosis occurred in response to valproate in PELs that supported lytic replication of HHV-8. The anti-viral agents ganciclovir and phosphonoformic acid (PFA) blocked valproate-induced production of infectious virus without blocking entry into the lytic cascade, and apoptosis occurred at levels that were as high as when virus production was not blocked. Ganciclovir and PFA also prevented most valproate-induced expression of the late lytic viral transcript open reading frame 26 (ORF-26), but they did not block the induction of either viral interleukin-6 (vIL-6) or viral G protein-coupled receptor (vGPCR). These studies provide evidence that incubation of PELs with valproate in the presence of ganciclovir or PFA can selectively target tumor cells for apoptosis without increasing viral load.
Failure of SCID-X1 gene therapy in older patients
Authors: Thrasher Adrian J. , Hacein-Bey-Abina Salima , Gaspar H. Bobby , Blanche Stephane , Davies E. Graham , Parsley Kathryn , Gilmour Kimberly , King Douglas , Howe Steven , Sinclair Joanna , Hue Christophe , Carlier Frédérique , von Kalle Christof , de Saint Basile Geneviève , le Deist Françoise , Fischer Alain , Cavazzana-Calvo Marina
Published: February 2005

Gene therapy has been shown to be a highly effective treatment for infants with typical X-linked severe combined immunodeficiency (SCID-X1, γc-deficiency). For patients in whom previous allogeneic transplantation has failed, and others with attenuated disease who may present later in life, the optimal treatment strategy in the absence of human leukocyte antigen (HLA)–matched donors is unclear. Here we report the failure of gene therapy in 2 such patients, despite effective gene transfer to bone marrow CD34+ cells, suggesting that there are intrinsic host-dependent restrictions to efficacy. In particular, there is likely to be a limitation to initiation of normal thymopoiesis, and we therefore suggest that intervention for these patients should be considered as early as possible.
GeneNotes – A novel information management software for biologists
Authors: Hong Pengyu , Wong Wing H
Published: February 2005

Background

Collecting and managing information is a challenging task in a genome-wide profiling research project. Most databases and online computational tools require a direct human involvement. Information and computational results are presented in various multimedia formats (e.g., text, image, PDF, word files, etc.), many of which cannot be automatically processed by computers in biologically meaningful ways. In addition, the quality of computational results is far from perfect and requires nontrivial manual examination. The timely selection, integration and interpretation of heterogeneous biological information still heavily rely on the sensibility of biologists. Biologists often feel overwhelmed by the huge amount of and the great diversity of distributed heterogeneous biological information.

Description

We developed an information management application called GeneNotes. GeneNotes is the first application that allows users to collect and manage multimedia biological information about genes/ESTs. GeneNotes provides an integrated environment for users to surf the Internet, collect notes for genes/ESTs, and retrieve notes. GeneNotes is supported by a server that integrates gene annotations from many major databases (e.g., HGNC, MGI, etc.). GeneNotes uses the integrated gene annotations to (a) identify genes given various types of gene IDs (e.g., RefSeq ID, GenBank ID, etc.), and (b) provide quick views of genes. GeneNotes is free for academic usage. The program and the tutorials are available at: http://bayes.fas.harvard.edu/genenotes/.

Conclusions

GeneNotes provides a novel human-computer interface to assist researchers to collect and manage biological information. It also provides a platform for studying how users behave when they manipulate biological information. The results of such study can lead to innovation of more intelligent human-computer interfaces that greatly shorten the cycle of biology research.
A novel pancoronavirus RT-PCR assay: frequent detection of human coronavirus NL63 in children hospitalized with respiratory tract infections in Belgium
Authors: Moës Elien , Vijgen Leen , Keyaerts Els , Zlateva Kalina , Li Sandra , Maes Piet , Pyrc Krzysztof , Berkhout Ben , van der Hoek Lia , Van Ranst Marc
Published: February 2005

Background

Four human coronaviruses are currently known to infect the respiratory tract: human coronaviruses OC43 (HCoV-OC43) and 229E (HCoV-229E), SARS associated coronavirus (SARS-CoV) and the recently identified human coronavirus NL63 (HCoV-NL63). In this study we explored the incidence of HCoV-NL63 infection in children diagnosed with respiratory tract infections in Belgium.

Methods

Samples from children hospitalized with respiratory diseases during the winter seasons of 2003 and 2004 were evaluated for the presence of HCoV-NL63 using a optimized pancoronavirus RT-PCR assay.

Results

Seven HCoV-NL63 positive samples were identified, six were collected during January/February 2003 and one at the end of February 2004.

Conclusions

Our results support the notation that HCoV-NL63 can cause serious respiratory symptoms in children. Sequence analysis of the S gene showed that our isolates could be classified into two subtypes corresponding to the two prototype HCoV-NL63 sequences isolated in The Netherlands in 1988 and 2003, indicating that these two subtypes may currently be cocirculating.
Postpartum maternal morbidity requiring hospital admission in Lusaka, Zambia – a descriptive study
Authors: Vallely Lisa , Ahmed Yusuf , Murray Susan F
Published: February 2005

Background

Information on the extent of postpartum maternal morbidity in developing countries is extremely limited. In many settings, data from hospital-based studies is hard to interpret because of the small proportion of women that have access to medical care. However, in those areas with good uptake of health care, the measurement of the type and incidence of complications severe enough to require hospitalisation may provide useful baseline information on the acute and severe morbidity that women experience in the early weeks following childbirth. An analysis of health services data from Lusaka, Zambia, is presented.

Methods

Six-month retrospective review of hospital registers and 4-week cross-sectional study with prospective identification of postpartum admissions.

Results

Both parts of the study identified puerperal sepsis and malaria as, respectively, the leading direct and indirect causes of postpartum morbidity requiring hospital admission. Puerperal sepsis accounted for 34.8% of 365 postpartum admissions in the 6-month period. Malaria and pneumonia together accounted for one-fifth of all postpartum admissions (14.5% & 6% respectively). At least 1.7% of the postpartum population in Lusaka will require hospital-level care for a maternal morbidity.

Conclusions

In developing country urban settings with high public health care usage, meticulous review of hospital registers can provide baseline information on the burden of moderate-to-severe postpartum morbidity.
Circulating γδ T cells in young/adult and old patients with cutaneous primary melanoma
Authors: Re Francesca , Donnini Alessia , Bartozzi Beatrice , Bernardini Giovanni , Provinciali Mauro
Published: February 2005

Background

In a previous study we demonstrated the existence of numerical and functional alterations of γδ T cells in healthy elderly. Recently, we analysed the involvement of γδ T lymphocytes in malignant melanoma, describing a lower frequency of circulating γδ T cells, an altered pattern of cytokine production, and an impaired in vitro expansion of these cells in primary cutaneous melanoma patients.

Methods

In this study we investigated the existence of numerical and functional alterations of circulating γδ T cells in young/adult and old melanoma patients, comparing the data obtained with age-matched healthy subjects.

Results

We demonstrated that the number of circulating γδ+T cells was significantly and similarly reduced in young/adult and old melanoma patients and in old healthy subjects in comparison with young healthy donors. The decrease was due to a reduction of Vδ2 T cells whereas the number of Vδ1 T cells was not affected. A higher percentage of γδ+T cells producing TNF-α was found in old healthy donors, whereas a reduced number of TNF-α-producing γδ+T cells was present in melanoma patients independently by age. No significant difference was observed in IFN-γ production. After a 10-day in vitro culture, both the percentage and the expansion index of γδ T cells, and in particular of Vδ2 subset, were significantly and similarly reduced both in young/adult and old melanoma patients, and in healthy aged people, in comparison with young/adult healthy subjects.

Conclusions

Our study demonstrates that the numerical and functional impairment of γδ T cells found in melanoma patients is not correlated with age and that it has characteristics very similar to the alterations of γδ T cells found in old healthy subjects. We suggest that a similar impairment of γδ T cell population may be related to the increased susceptibility to tumors present in the elderly as well as in the pathogenesis of malignant melanoma.
Annals of General Psychiatry
Authors: Fountoulakis Konstantinos
Published: February 2005

Our regular readers will notice that the title of our journal has changed from Annals of General Hospital Psychiatry (AGHP) to Annals of General Psychiatry (AGP) since January 1st, 2005. This was judged as necessary, in order to be able to serve better the aims of the journal. Our initial thoughts were that including the term 'General Hospital' in the journal's title would help us to launch a journal dedicated to the idea of Psychiatry as a medical specialty. But they were not justified; so, now the Annals of General Psychiatry (AGP) is born! It is still an Open Access, peer-reviewed, online journal covering the wider field of Psychiatry, Neurosciences and Psychological Medicine, and aims at publishing articles on all aspects of psychiatry. Primary research articles are the journal's priority, and both basic and clinical neuroscience contributions are encouraged. The AGP strongly supports and follows the principles of evidence-based medicine. AGP's articles are archived in PubMed Central, the US National Library of Medicine's full-text repository of life science literature, and also in repositories at the University of Potsdam in Germany, at INIST in France and in e-Depot, the National Library of the Netherlands' digital archive of all electronic publications. We hope that the change in the journal's name will cure the confusion caused by its previous title and help to achieve the journal's aims and scope, that is to help the world-wide promotion of research and publishing in the mental health area.
Proteinase-Activated Receptors: Transducers of Proteinase-Mediated Signaling in Inflammation and Immune Response
Authors: Steinhoff Martin , Buddenkotte Jörg , Shpacovitch Victoria , Rattenholl Anke , Moormann Corinna , Vergnolle Nathalie , Luger Thomas A. , Hollenberg Morley D.
Published: February 2005

Serine proteinases such as thrombin, mast cell tryptase, trypsin, or cathepsin G, for example, are highly active mediators with diverse biological activities. So far, proteinases have been considered to act primarily as degradative enzymes in the extracellular space. However, their biological actions in tissues and cells suggest important roles as a part of the body’s hormonal communication system during inflammation and immune response. These effects can be attributed to the activation of a new subfamily of G protein-coupled receptors, termed proteinase-activated receptors (PARs). Four members of the PAR family have been cloned so far. Thus, certain proteinases act as signaling molecules that specifically regulate cells by activating PARs. After stimulation, PARs couple to various G proteins and activate signal transduction pathways resulting in the rapid transcription of genes that are involved in inflammation. For example, PARs are widely expressed by cells involved in immune responses and inflammation, regulate endothelial-leukocyte interactions, and modulate the secretion of inflammatory mediators or neuropeptides. Together, the PAR family necessitates a paradigm shift in thinking about hormone action, to include proteinases as key modulators of biological function. Novel compounds that can modulate PAR function may be potent candidates for the treatment of inflammatory or immune diseases.
Fibroblast Growth Factor Signaling during Early Vertebrate Development
Authors: Böttcher Ralph T. , Niehrs Christof
Published: February 2005

Fibroblast growth factors (FGFs) have been implicated in diverse cellular processes including apoptosis, cell survival, chemotaxis, cell adhesion, migration, differentiation, and proliferation. This review presents our current understanding on the roles of FGF signaling, the pathways employed, and its regulation. We focus on FGF signaling during early embryonic processes in vertebrates, such as induction and patterning of the three germ layers as well as its function in the control of morphogenetic movements.
Functional analysis of TbARL1, anN-myristoylated Golgi protein essential for viability in bloodstream trypanosomes
Authors: Price Helen P. , Panethymitaki Chrysoula , Goulding David , Smith Deborah F.
Published: February 2005

Myristoyl-CoA:protein N-myristoyltransferase (NMT), an essential protein in Trypanosoma brucei and Leishmania major, catalyses the covalent attachment of the fatty acid myristate to the N-terminus of a range of target proteins. In order to define the essential targets contributing to lethality in the absence of NMT activity, we have focused on the ADP-ribosylation factor (Arf) family of GTP-binding proteins, as growth arrest in Saccharomyces cerevisiae mutants with reduced NMT activity correlates with a decrease in N-myristoylated Arf proteins. We have identified nine Arf/Arls in the T. brucei and T. cruzi genomes and ten in L. major. Characterization of the T. brucei ARL1 homologue has revealed that the protein is localized in the Golgi apparatus and is expressed only in the mammalian bloodstream form of the parasite and not in the insect procyclic stage. This is the only reported example to date of a differentially expressed ARL1 homologue in any species. We have used RNA interference to demonstrate that ARL1 is essential for viability in T. brucei bloodstream parasites. Prior to cell death, depletion of ARL1 protein in bloodstream parasites results in abnormal morphology, including disintegration of the Golgi structure, multiple flagella and nuclei, and the presence of large numbers of vesicles. The cells have only a minor apparent defect in endocytosis but exocytosis of variant surface glycoprotein to the parasite surface is significantly delayed. RNA interference of ARL1 in procyclic cells has no effect on parasite growth or morphology. Our results suggest that there may be different pathways regulating Golgi structure and function in the two major life cycle stages of T. brucei.
The Tie-2 ligand Angiopoietin-2 destabilizes quiescent endothelium through an internal autocrine loop mechanism
Authors: Scharpfenecker Marion , Fiedler Ulrike , Reiss Yvonne , Augustin Hellmut G.
Published: February 2005

The angiopoietins Ang-1 and Ang-2 have been identified as ligands of the endothelial receptor tyrosine kinase Tie-2, which controls vascular assembly and endothelial quiescence. The largely complementary phenotypes of Ang-1-deficient mice and Ang-2-overexpressing mice have led to an antagonistic model in which Ang-1 acts as Tie-2-activating agonist and Ang-2 acts as a Tie-2-inhibiting antagonist. To date, no mechanistic equivalent of the antagonistic Ang-1/Ang-2 model has been established and the mechanisms of Ang-2 function in particular remain mysterious. We have studied the effector functions of Ang-1 and Ang-2 on quiescent endothelial cells using a three-dimensional co-culture model of endothelial cells and smooth-muscle cells. Endothelial-cell monolayer integrity in this model is dependent on Tie-2 signaling, as evidenced by detaching endothelial cells following exposure to the small molecular weight Tie-2 inhibitor A-422885.66, which cannot be overcome by exogenous Ang-1. Accordingly, exogenous Ang-2 rapidly destabilizes the endothelial layer, which can be observed within 30-60 minutes and leads to prominent endothelial-cell detachment within 4 hours. Exogenous Ang-2-mediated endothelial-cell detachment can be rescued by Ang-1, soluble Tie-2 and vascular endothelial growth factor. Similar findings were obtained in an umbilical-vein explant model. Ang-2 is mainly produced by endothelial cells and therefore acts primarily in an autocrine manner. Thus, stimulated release of endogenous Ang-2 or overexpression of Ang-2 in endothelial cells perturbs co-culture spheroid integrity, which can be rescued by exogenous Ang-1 and vascular endothelial growth factor. However, autocrine Ang-2-mediated endothelial-cell detachment cannot be blocked by soluble Tie-2. Taken together, the data demonstrate for the first time the antagonistic Ang-1/Ang-2 concept in a defined cellular model and identify Ang-2 as a rapidly acting autocrine regulator of the endothelium that acts through an internal autocrine loop mechanism.
Ectopic mTERT expression in mouse embryonic stem cells does not affect differentiation but confers resistance to differentiation- and stress-induced p53-dependent apoptosis
Authors: Lee Ming Kei , Hande M. Prakash , Sabapathy Kanaga
Published: February 2005

The fundamental role of telomerase is to protect telomere ends and to maintain telomere length during replication; hence, telomerase expression is high in stem cells but reduced upon differentiation. Recent studies indicate that telomerase might play other roles besides telomere maintenance. We have investigated the role of telomerase in cellular differentiation and death. Here, we show that ectopic expression of mouse telomerase catalytic subunit (mTERT) does not affect embryonic stem (ES) cell proliferation or differentiation in vitro, but protects ES cells against cell death during differentiation. Ectopic mTERT expression also confers resistance to apoptosis induced by oxidative stress and other genotoxic insults. This resistance depends on the catalytic activity of mTERT. Stress-signal-induced p53 accumulation and consequent p53-dependent apoptotic target gene expression was not affected by mTERT overexpression. However, although chemical inhibition of p53 by α-pifithrin reduced stress-induced apoptosis in vector-expressing cells, it did not significantly affect apoptosis in mTERT-expressing cells. Moreover, overexpression of mTERT in p53–/– ES cells did not confer further resistance to genotoxic insults, suggesting that mTERT might exert its protective effect by antagonizing the p53 pathway. Altogether, our findings indicate that ectopic mTERT expression in ES cells does not affect differentiation but confers resistance to apoptosis, and suggest that this strategy might be used in improving the efficiency of stem-cell therapies.
Intraoperative colonic lavage in emergency surgical treatment of left-sided large bowel lesions
Authors: Edino S T , Mohammed A Z , Anumah M
Published: February 2005

There has been a trend towards resection and primary anastomosis after on-table lavage in patients with left sided colonic emergencies. This study will analyse the outcome in our centre. Thirty-two patients underwent the operation for various lesions of the left colon and the rectum between December 1998 and December 2002. The mean age of the patients was 37.7 ± 11.1 years. Mean extra time for the procedure was 37.4 ± 5.2 min. The mean hospital stay was 11.2 ± 2.9 days. Postoperative complications included four cases (12.5%) of wound infection, and one (3.1%) right sub-phrenic abscess. No clinical anastomotic leakage or mortality was recorded. This study shows that primary anastomosis with on-table colonic lavage can be a safe procedure in selected, low risk patients.
Bone and joint TB at Queen Elizabeth Central Hospital 1986 to 2002
Authors: Mkandawire N C , Kaunda E
Published: February 2005

A retrospective audit of all cases of bone and joint TB registered in the TB office at Queen Elizabeth Central Hospital (QECH) from 1986 to 2002 was conducted with the aim of quantifying the proportion of bone and joint TB. The study period coincides with that of the HIV pandemic.

A total of 37 075 cases were recorded with 599 (1.6%) involving the skeletal system; of the skeletal TB, 90% involved the spine. The absolute numbers of skeletal TB have remained relatively constant, fluctuating between 14 and 58 per year, while the total number of cases has progressively increased from 657 in 1986 to 3469 in 2002.
Maternal mortality at B P Koirala Institute of Health Sciences, Nepal: Review of 6 years
Authors: Sharma Mona , Uprety Dhruba , Pokhrel Monalisa , Karki Anjana , Sharma Usha , Babu Suresh
Published: February 2005

This study aimed to find out the maternal mortality rate (MMR) in mothers dying after admission to the gynaecology and obstetrics ward of BP Koirala Institute of Health Sciences, Nepal, and to analyse the most common causative factor. There was a total of 58 mortality cases in 6 years. The MMR in 1997-1998 was 12/100 000 live births, in 1998-1999 144/100 000, in 1999-2000 294/100 000, in 2000-2001 450/100 000, in 2001-2002 546/100 000 and in 2002-2003 400/100 000. The most common cause of death was septic-induced abortion and its complications, followed by eclampsia and puerperal sepsis.
‘We want someone with a face of welcome’: Ugandan adolescents articulate their family planning needs and priorities
Authors: Flaherty Annette , Kipp Walter , Mehangye Idah
Published: February 2005

In this article, the attitudes, needs and priorities of adolescents in family planning, as articulated by them during focus group discussions, are presented. Findings indicate that: (a) Ugandan adolescents face numerous barriers to accessing family planning information and services; (b) they hold an alarming number of misconceptions about modern contraceptives; (c) they lack reliable, trusted and non-judgemental sources of information, privacy and confidentiality during family planning counselling, and (d) they don't know about contraceptive services available from the community-based distributors. Suggestions are provided on how community-based distributors could improve their outreach to adolescents and provide youth-friendly family planning services.
Excision of a 1.9 kg goitre under local anaesthetic
Authors: Hodges Andrew M
Published: February 2005

A 30-year-old woman with a large goitre underwent thyroidectomy under local anaesthetic field block. A 1.9 kg goitre was resected. She was given light sedation but was able to communicate throughout the whole procedure which was performed comfortably under the local anaesthesia. She made an uneventful recovery with no complications. Local anaesthetic was chosen as the safest procedure in a remote rural Ugandan hospital which lacked close post-operative monitoring. Other benefits of using local anaesthesia are discussed.