bluuebunny/crossref_metadata_2025 huggingface dataset:
Sympathy in Space(s)
Authors: Forman-Barzilai Fonna
Published: February 2005

In this essay the author explores the relation between sympathy and proximity in Adam Smith’s Theory of Moral Sentiments. The essay proceeds in two parts. First, the author demonstrates that Smith’s description of our various attachments and affections, and the inevitable conflicts among them, draws us into the rich spatial texture of sympathetic response and stimulates further inquiry into a variety of spaces in which sympathetic activity takes place. In the second part, the author explores three such spaces—the physical, the affective, and the historical/cultural—to critique the way that some contemporary moral and political theorists have appropriated Smith’s account of sympathy as a tool for cosmopolitan aspirations. To what extent can Smith’s sympathy model detach us from and get us beyond the partiality and particularity generated by our physical, affective, and cultural entanglements
“We Feel Our Freedom”
Authors: Zerilli Linda M. G.
Published: February 2005

Critics of Hannah Arendt’s Lectures on Kant’s Political Philosophy argue that Arendt fails to address the most important problem of political judgment, namely, validity. This essay shows that Arendt does indeed have an answer to the problem that preoccupies her critics, with one important caveat: she does not think that validity is the all-important problem of political judgment—the affirmation of human freedom is.
Childhood and Adolescent Mobility and Adult Relations With Parents
Authors: Myers Scott M.
Published: February 2005

This study addresses three questions: Does earlier family mobility have long-term effects on later parent-adult offspring relations? Do differences in parenting behaviors and family social capital account for these effects? Does the family structure in which a move occurs matter? The author investigates these issues using 17-year longitudinal data from two generations. The results suggest that frequency of family mobility has no effects on parent-adult child relations. Instead, it appears that age at mobility matters most. Adult sons who moved during adolescence and during both childhood and adolescence have poorer relationships with their mothers and fathers. Earlier mobility, though, generally has no associations with an adult daughter’s relationship with her parents. For sons and daughters, moves that occur in divorced households are the most difficult on later parent-adult child relations. Some, but not all, of the long-term effects of family mobility are because of differences in parenting between movers and nonmovers.
To Marry or Not to Marry
Authors: Baxter Janeen
Published: February 2005

Data from an Australian national survey (1996 to 1997) are used to examine domestic labor patterns among de facto and married men and women. The results show that women spend more time on housework and do a greater proportion of housework than men. However, the patterns are most traditional among married men and women. Women in de facto relationships spend less time doing housework and do a smaller proportion of indoor activities than married women. Men in de facto relationships do a larger proportion of indoor activities and a lower proportion of outdoor tasks than married men. The data also show that couples who have cohabited prior to marriage have more egalitarian divisions of labor than those who have not cohabited prior to marriage. This article concludes by arguing that the incompleteness of the de facto relationship provides a period of relative freedom in which to negotiate more equal roles.
Medical Students’ and Tutors’ Experiences of Directed and Self-Directed Learning Programs in Evidence-Based Medicine
Authors: Bradley Peter , Oterholt Christina , Nordheim Lena , Bjørndal Arild
Published: February 2005

This qualitative study aims to interpret the results of a randomized controlled trial comparing two educational programs (directed learning and self-directed learning) in evidence-based medicine (EBM) for medical students at the University of Oslo from 2002 to 2003. There is currently very little comparative educational research in this field. In the trial, no statistically significant differences between the study groups were shown for any outcomes considered (EBM knowledge, skills, and attitudes). Further analysis suggests that main reason for the negative trial results was that the majority of students learned equally effectively, whichever program they received, although implementation of the educational programs was not complete because of varying attendance. This study illustrates a stepwise evaluation model that might be useful in evaluating other socially complex interventions.
Intracellular interaction of von Willebrand factor and factor VIII depends on cellular context: lessons from platelet-expressed factor VIII
Authors: Yarovoi Helen , Nurden Alan T. , Montgomery Robert R. , Nurden Paquita , Poncz Mortimer
Published: February 2005

We have previously reported that ectopically expressed factor VIII (FVIII) is stored within platelets and is released upon platelet activation. Studies by others in various cell lines have suggested that having von Willebrand factor (VWF) coexpression is necessary for FVIII granular storage and for its secretion. We tested the importance of VWF coexpression for ectopic storage of FVIII in platelets and for its bioavailability. Transgenic mice expressing platelet-specific FVIII were crossed onto a VWF-/- background. Antigenic levels of platelet FVIII in these mice were nearly unchanged whether VWF was present or not. Whole-blood clotting times and FeCl3 carotid artery injury correction demonstrated that platelet FVIII demonstrably improved the bleeding diathesis in FVIIInull mice independent of the platelets' VWF status. Immunogold electron microscopy demonstrated that platelet FVIII is stored in platelet α-granules independent of the presence of VWF. It appears that FVIII's interaction with VWF and its intracellular transportation, storage, and secretion differ greatly depending on the cell type. The molecular basis for these differences now needs to be elucidated. (Blood. 2005;105:4674-4676)
Abdominal fat and hip fracture risk in the elderly: The Dubbo Osteoporosis Epidemiology Study
Authors: Nguyen Nguyen D , Pongchaiyakul Chatlert , Center Jacqueline R , Eisman John A , Nguyen Tuan V
Published: February 2005

Background

Fat mass, which is a major component of body weight, is directly related to bone mineral density and reduced fracture risk. It is not known whether abdominal fat is associated with hip fracture. The present study was designed to examine the association between abdominal fat and hip fracture in women and men aged 60+ years.

Methods

This was a nested case-control study with one fracture case being matched with two controls of the same age. In women 63 cases were matched with 126 controls, and in men 26 cases were matched with 52 controls. Hip fracture was confirmed by X-ray and personal interview. Other measurements included weight, height, body mass index (BMI), abdominal fat, and femoral neck bone density (FNBMD). Conditional logistic regression model was used to analyse data.

Results

The odds ratio of hip fracture risk associated with each 10% lower abdominal fat was 1.5 (95% CI, 1.1 to 2.1) in women and 1.2 (95% CI, 0.7 to 2.0) in men. However after adjusting for FNBMD or body weight, the abdominal fat-fracture association was no longer statistically significant. Similarly, body weight and BMI was each significantly associated with hip fracture risk (in women), but after taking with account the effect of FNBMD, the association become statistically non-significant.

Conclusion

Lower abdominal fat was associated with an increased risk of hip fracture in elderly women, but the association was not independent of FNBMD or weight. The contribution of abdominal fat to hip fracture risk is likely to be modest.
Synergistic inhibition of human cytomegalovirus replication by interferon-alpha/beta and interferon-gamma
Authors: Sainz Bruno , LaMarca Heather L , Garry Robert F , Morris Cindy A
Published: February 2005

Background

Recent studies have shown that gamma interferon (IFN-γ) synergizes with the innate IFNs (IFN-α and IFN-β) to inhibit herpes simplex virus type 1 (HSV-1) replicationin vitro. To determine whether this phenomenon is shared by other herpesviruses, we investigated the effects of IFNs on human cytomegalovirus (HCMV) replication.

Results

We have found that as with HSV-1, IFN-γ synergizes with the innate IFNs (IFN-α/β) to potently inhibit HCMV replicationin vitro. While pre-treatment of human foreskin fibroblasts (HFFs) with IFN-α, IFN-β or IFN-γ alone inhibited HCMV plaque formation by ~30 to 40-fold, treatment with IFN-α and IFN-γ or IFN-β and IFN-γ inhibited HCMV plaque formation by 163- and 662-fold, respectively. The generation of isobole plots verified that the observed inhibition of HCMV plaque formation and replication in HFFs by IFN-α/β and IFN-γ was a synergistic interaction. Additionally, real-time PCR analyses of the HCMV immediate early (IE) genes (IE1 and IE2) revealed that IE mRNA expression was profoundly decreased in cells stimulated with IFN-α/β and IFN-γ (~5-11-fold) as compared to vehicle-treated cells. Furthermore, decreased IE mRNA expression was accompanied by a decrease in IE protein expression, as demonstrated by western blotting and immunofluorescence.

Conclusion

These findings suggest that IFN-α/β and IFN-γ synergistically inhibit HCMV replication through a mechanism that may involve the regulation of IE gene expression. We hypothesize that IFN-γ produced by activated cells of the adaptive immune response may potentially synergize with endogenous type I IFNs to inhibit HCMV disseminationin vivo.
Stimulation of P2X receptors enhances lipooligosaccharide-mediated apoptosis of endothelial cells
Authors: Sylte Matt J , Kuckleburg Chris J , Inzana Thomas J , Bertics Paul J , Czuprynski Charles J
Published: February 2005

Exposure of endothelial cells to lipid A-containing molecules, such as lipopolysaccharide (LPS) or lipooligosaccharide (LOS), causes the release of purinergic compounds [e.g., adenosine 5′-triphosphate (ATP)] and can lead to apoptosis. The P2X family of purinergic receptors (e.g., P2X7) has been reported to modulate LPS signaling events and to participate in apoptosis. We investigated the role that P2X receptors play in the apoptosis that follows exposure of bovine endothelial cells to Haemophilus somnus LOS. Addition of P2X inhibitors, such as periodate-oxidized ATP (oATP) or pyridoxal-phosphate-6-azophenyl-2′,4′-disulfonic acid tetrasodium, significantly reduced LOS-induced apoptosis. Incubation of endothelial cells with apyrase, which degrades ATP, diminished LOS-induced apoptosis of endothelial cells. Concomitant addition of P2X agonists [e.g., 2′,3′-(4-benzoyl)-benzoyl ATP or ATP] to LOS-treated endothelial cells significantly enhanced caspase-3 activation. The P2X antagonist oATP significantly blocked caspase-8 but not caspase-9 activation in LOS-treated endothelial cells. Together, these data indicate that stimulation of P2X receptors enhances LOS-induced apoptosis of endothelial cells, possibly as a result of endogenous release of ATP, which results in caspase-8 activation.
Endometrial Angiogenesis: From Physiology to Pathology
Authors: KRIKUN G , SCHATZ F , LOCKWOOD C J
Published: February 2005

Abstract: Numerous factors have been implicated in angiogenesis. This article concentrates on the expression of the major angiogenic factors, namely, vascular endothelial growth factor (VEGF) and the angiopoietins in the human endometrium. Particular emphasis is placed on the expression of the angiopoietins and their physiological and pathological expression.
Molecular Regulation of Müllerian Development by Hox Genes
Authors: DU HONGLING , TAYLOR HUGH S.
Published: February 2005

Abstract: HOX genes are a family of regulatory molecules that encode conserved transcription factors controlling aspects of morphogenesis and cell differentiation during normal embryonic development. All metazoans possess a common genetic system for embryonic patterning, and this system is also used in the reproductive tract. Hox genes are also expressed in the adult uterus. Hox genes are essential both for the development of müllerian tract in the embryonic period and adult function. Sex steroids regulate Hox gene expression during embryonic and endometrial development in the menstrual cycle. EMX2 and β3‐integrin acting downstream of Hoxa10 gene are likely involved in both these developmental processes. This article reviews the role and molecular regulation of Hox genes in reproductive tract development.
Leukemia Inhibitory Factor and Human Embryo Implantation
Authors: AGHAJANOVA LUSINE
Published: February 2005

Abstract: The success of embryonic implantation relies on an ideal cross‐talk between the embryo and the receptive endometrium. This article focuses on the role of leukemia inhibitory factor (LIF) and its receptors in human embryo implantation. LIF is a secreted glycoprotein first described as a factor that induced the differentiation of mouse myeloid leukemic M1 cells into macrophages and later proposed as a marker of the embryo implantation process. An important role for LIF in implantation was shown on LIF knockout mice, when embryo implantation did not occur. In endometrium of healthy women, LIF and LIF mRNA are expressed throughout the menstrual cycle with a striking increase in the midsecretory phase, coinciding with a supposed window of implantation. Correlation in the expression of LIF and some other markers of implantation has been reported. LIF acts on cells by binding to the LIF receptor (LIFR) and gp130. Human blastocysts express mRNAs for LIFR and gp130, participating actively in establishing contact with the endometrium. In the endometrium, LIFR and gp130 are expressed in the endometrial epithelium throughout the cycle with strong increase in the midsecretory phase. Endometrium of infertile women produces significantly less LIF during the period of receptivity. The role of LIF gene mutations in unexplained infertility and implantation failures in IVF patients is not clear yet. Infertile patients showed reduced secretion of LIFR and gp130 compared with fertile controls during the implantation window. Recombinant human LIF might help to improve the implantation rate in women with unexplained infertility.
Implantation Failure in Assisted Reproduction Technology and a Critical Approach to Treatment
Authors: LEVI SETTI P E , COLOMBO G V , SAVASI V , BULLETTI C , ALBANI E , FERRAZZI E
Published: February 2005

Abstract: In this article, we review the literature and our personal experience regarding the many factors that appear to influence implantation rate. Oocyte quality, as determined by patient age and aneuploidies, probably plays a major role in RIF. However, a panoply of other factors have been brought under investigation, quite often with contradictory results and additional intriguing questions to be studied. Infections of the vagina, cervix, and endometrium, the role of mucus aspiration and washing of the cervix on transfer, the role of catheter guidance for a correct transfer and potion of embryos, the effect of mock transfer, and the role of hysteroscopy and its timing before transfer procedures are analyzed both as a review of the literature and as opinions and data from our experience. Many of these factors are interlaced and from the apparently simple issue of trauma, to infections and immune modulation of hatching and implantation, a biological continuum can easily be identified. The impact of abnormalities of the immune system and of homeostasis abnormalities is also covered in a brief overview of reported works and our experience. These latter areas probably constitute the common biological background of all other external factors that, however, the skilled must equip themselves for improving implantation success.
Natural In Vitro Fertilization Cycles
Authors: UBALDI FILIPPO , RIENZI LAURA , FERRERO SUSANNA , BARONI ELENA , IACOBELLI MARCELLO , SAPIENZA FABIO , MINASI MARIA GIULIA , COBELLIS LUIGI , ROMANO STEFANIA , SCARSELLI FILOMENA , GRECO ERMANNO
Published: February 2005

Abstract: Although the first in vitro fertilization (IVF) baby was born after a natural IVF cycle, very soon this procedure was almost abandoned mainly because of the very high cancellation rates, and controlled pharmacological ovarian hyperstimulation became the standard treatment in IVF cycles of normoresponder patients. However, in poor‐responder patients, where only very few follicles can be recruited and very few oocytes, if any, can be retrieved after controlled ovarian hyperstimulation, natural IVF cycles may offer a comparable number of follicles, reduced costs, and less discomfort for the patients. In this group of patients, natural IVF cycle is a cost‐effective approach.
Number of Embryos Transferred and Implantation
Authors: GIANNINI PIERLUIGI , PISCITELLI CLAUDIO , GIALLONARDO ANNALISE , SBRACIA MARCO , MORGIA FRANCESCO , TORTI MONICA , MONTIGIANI MONICA , SCHIMBERNI MAURO
Published: February 2005

Abstract: Multiple pregnancies are considered the most frequent and serious complication of assisted reproduction technology. To reduce the frequency of multiple pregnancies, several centers have adopted a policy of reducing the number of embryos transferred in the uterus, suggesting single embryo transfer. Even though a significant number of papers have been published on this issue, no general consensus exists on how many embryos to replace in the uterus and at which cleavage stage. We conducted a retrospective study on cycles performed throughout 2003, analyzing the relation between the number of embryos transferred and the pregnancy and implantation rates, evaluating also the role of the woman's age. No differences were found among the groups except in one‐embryo transferred women, which were mostly natural cycles, for estradiol levels, number of mature oocytes retrieved, number of top quality embryos, and pregnancy rate. The implantation rate was significantly higher in the two‐embryo transfers versus three‐embryo transfers. We found higher pregnancy and implantation rates with similar multiple pregnancy rates in patients where only two embryos were transferred versus three embryos transfer when women were less than 35 years old. In women aged less than 35 years, which in turn have the higher expectancy of successful pregnancy and also the higher risk of multiple pregnancy, the single embryo transfer is a suitable choice for these patients.
Surgical Management of Deeply Infiltrating Endometriosis: An Update
Authors: CHAPRON CHARLES , CHOPIN NICOLAS , BORGHESE BRUNO , MALARTIC CECILE , DECUYPERE FOUZIA , FOULOT HERVE
Published: February 2005

Abstract: Deeply infiltrating endometriosis (DIE) manifests itself mainly in the form of pain, predominantly deep dyspareunia, and painful functional symptoms that are aggravated monthly during menstruation, with the semiology being directly correlated with the location of the lesions (bladder, rectum). A workup to assess the extent of the disease is necessary to establish an accurate map of the DIE lesions, which is the essential condition to perform complete exeresis. The treatment of first intention is surgical, because medical treatments are only palliative in the majority of cases. Successful treatment depends on achieving radical surgical exeresis. Analysis of the anatomical distribution of the DIE lesions allows a “surgical classification” to be proposed to standardize the modalities of surgical treatment. Further studies are needed to specify the place and modalities of medical treatments preoperatively and postoperatively.
Subarachnoid Analgesia in Advanced Labor: A Comparison of Subarachnoid Analgesia and Pudendal Block in Advanced Labor: Analgesic Quality and Obstetric Outcome
Authors: PACE MARIA CATERINA , AURILIO CATERINA , BULLETTI CARLO , IANNOTTI MARIO , PASSAVANTI MARIA BEATRICE , PALAGIANO ANTONIO
Published: February 2005

Abstract: Pain control during labor is a primary objective of antalgic therapy. The use of the peridural as an elective procedure for labor analgesia is now corroborated by the international scientific community. Sometimes a combined spinal‐peridural procedure is used together with the intrathecal administration of opioids to also cover the first stage of labor. Unfortunately, patients and/or gynecologists often request analgesia in a late stage of labor. The aim of our study was to evaluate the possibility of using a subarachnoid block alone for labor analgesia when this is requested at a late stage, that is, in advanced labor with cervical dilation greater than 7 cm. After approval by our ethics committee and the written and informed consent of the patients, 111 women were enrolled in this study and randomly divided into two groups. The first group (Group S: 55 patients) received a subarachnoid block with 2.5 mg hyperbaric bupivacaine + 25 μg fentanyl + 1 mL 10% glucose. A pudendal nerve block with 7 mL 2% mepivacaine in each side was administered to the second group (Group P: 56 patients). In both groups, careful maternal‐fetal monitoring was conducted, and pain was scored on a numerical scale from 0 to 4, 10 minutes after placement of the block (time [T] 0), at delivery (T1), and at episiorrhaphy (T2). In all patients, we recorded any side effects, the Apgar score at birth and after 5 minutes, the administration of other analgesic and/or sedative drugs, the degree of satisfaction, and the time of hospitalization after delivery. Evaluations were performed by anesthesiologists unaware of patients' treatment group. The duration of spinal analgesia was considered to be the time from injection of study drugs to the time of the patient's first request for additional analgesia. In no cases were there any side effects worthy of note, and hospitalization never exceeded 72 hours. The Apgar score was always between 7 and 10. All except one of the women in Group S were satisfied or more than satisfied with their pain management, whereas 50 women in Group P expressed only moderate satisfaction or dissatisfaction (P < 0.0001). In most patients in Group S, complete analgesia was obtained. In Group P, however, 10 minutes after placement of the pudendal nerve block, 40 patients reported no improvement in pain symptomatology during contractions and only 16 reported less painful contractions (P < 0.0001). The duration of spinal analgesia (128 ± 38 minutes) was enough in most cases for delivery to be completed. These results suggest that low‐dose bupivacaine‐fentanyl spinal analgesia represents an important option for pain relief in late labor, not the least because the procedure does not upset the dynamics of delivery or alter vital parameters and is welcomed by women in labor who are still able to collaborate actively in the birth of their baby.
The hedgehog-PKA pathway regulates two distinct steps of the differentiation of retinal ganglion cells: the cell-cycle exit of retinoblasts and their neuronal maturation
Authors: Masai Ichiro , Yamaguchi Masahiro , Tonou-Fujimori Noriko , Komori Atsuko , Okamoto Hitoshi
Published: February 2005

In the developing zebrafish retina, neurogenesis is initiated in cells adjacent to the optic stalk and progresses to the entire neural retina. It has been reported that hedgehog (Hh) signalling mediates the progression of the differentiation of retinal ganglion cells (RGCs) in zebrafish. However, the progression of neurogenesis seems to be only mildly delayed by genetic or chemical blockade of the Hh signalling pathway. Here, we show that cAMP-dependent protein kinase (PKA) effectively inhibits the progression of retinal neurogenesis in zebrafish. Almost all retinal cells continue to proliferate when PKA is activated, suggesting that PKA inhibits the cell-cycle exit of retinoblasts. A cyclin-dependent kinase (cdk) inhibitor p27 inhibits the PKA-induced proliferation, suggesting that PKA functions upstream of cyclins and cdk inhibitors. Activation of the Wnt signalling pathway induces the hyperproliferation of retinal cells in zebrafish. The blockade of Wnt signalling inhibits the PKA-induced proliferation, but the activation of Wnt signalling promotes proliferation even in the absence of PKA activity. These observations suggest that PKA inhibits exit from the Wnt-mediated cell cycle rather than stimulates Wnt-mediated cell-cycle progression. PKA is an inhibitor of Hh signalling, and Hh signalling molecule morphants show severe defects in cell-cycle exit of retinoblasts. Together, these data suggest that Hh acts as a short-range signal to induce the cell-cycle exit of retinoblasts. The pulse inhibition of Hh signalling revealed that Hh signalling regulates at least two distinct steps of RGC differentiation: the cell-cycle exit of retinoblasts and RGC maturation. This dual requirement of Hh signalling in RGC differentiation implies that the regulation of a neurogenic wave is more complex in the zebrafish retina than in the Drosophila eye.
pitx3defines an equivalence domain for lens and anterior pituitary placode
Authors: Dutta Sunit , Dietrich Jens-Erik , Aspöck Gudrun , Burdine Rebecca D. , Schier Alexander , Westerfield Monte , Varga Zoltán M.
Published: February 2005

Hedgehog signaling is required for formation and patterning of the anterior pituitary gland. However, the role of Hedgehog in pituitary precursor cell specification and subsequent placode formation is not well understood. We analyzed pituitary precursor cell lineages and find that pitx3 and distal-less3b (dlx3b) expression domains define lens and pituitary precursor positions. We show that pitx3 is required for pituitary pre-placode formation and cell specification, whereas dlx3band dlx4b are required to restrict pituitary placode size. In smoothened mutant embryos that cannot transduce Hedgehog signals,median pituitary precursors are mis-specified and form an ectopic lens. Moreover, overexpression of sonic hedgehog (shh) blocks lens formation, and derivatives of lens precursors express genes characteristic of pituitary cells. However, overexpression of shh does not increase median pituitary placode size nor does it upregulate patched(ptc) expression in pituitary precursors during early somitogenesis. Our study suggests that by the end of gastrulation, pitx3-expressing cells constitute an equivalence domain of cells that can form either pituitary or lens, and that a non-Hedgehog signal initially specifies this placodal field. During mid-somitogenesis, Hedgehog then acts on the established median placode as a necessary and sufficient signal to specify pituitary cell types.
Identification of trichoplein, a novel keratin filament-binding protein
Authors: Nishizawa Miwako , Izawa Ichiro , Inoko Akihito , Hayashi Yuko , Nagata Koh-ichi , Yokoyama Tomoya , Usukura Jiro , Inagaki Masaki
Published: February 2005

Keratins 8 and 18 (K8/18) are major components of the intermediate filaments (IFs) of simple epithelia. We report here the identification of a novel protein termed trichoplein. This protein shows a low degree of sequence similarity to trichohyalin, plectin and myosin heavy chain, and is a K8/18-binding protein. Among interactions between trichoplein and various IF proteins that we tested using two-hybrid methods, trichoplein interacted significantly with K16 and K18, and to some extent with K5, K6a, K8 and K14. In in vitro co-sedimentation assays, trichoplein directly binds to K8/18, but not with vimentin, desmin, actin filaments or microtubules. An antibody raised against trichoplein specifically recognized a polypeptide with a relative molecular mass of 61 kDa in cell lysates. Trichoplein was immunoprecipitated using this antibody in a complex with K8/18 and immunostaining revealed that trichoplein colocalized with K8/18 filaments in HeLa cells. In polarized Caco-2 cells, trichoplein colocalized not only with K8/18 filaments in the apical region but also with desmoplakin, a constituent of desmosomes. In the absorptive cells of the small intestine, trichoplein colocalized with K8/18 filaments at the apical cortical region, and was also concentrated at desmosomes. Taken together, these results suggest that trichoplein is a keratin-binding protein that may be involved in the organization of the apical network of keratin filaments and desmosomes in simple epithelial cells.
MKKS/BBS6, a divergent chaperonin-like protein linked to the obesity disorder Bardet-Biedl syndrome, is a novel centrosomal component required for cytokinesis
Authors: Kim Jun Chul , Ou Young Y. , Badano Jose L. , Esmail Muneer A. , Leitch Carmen C. , Fiedrich Elsa , Beales Philip L. , Archibald John M. , Katsanis Nicholas , Rattner Jerome B. , Leroux Michel R.
Published: February 2005

Chaperonins are multisubunit, cylinder-shaped molecular chaperones involved in folding newly synthesized polypeptides. Here we show that MKKS/BBS6, one of several proteins associated with Bardet-Biedl syndrome (BBS), is a Group II chaperonin-like protein that has evolved recently in animals from a subunit of the eukaryotic chaperonin CCT/TRiC, and diverged rapidly to acquire distinct functions. Unlike other chaperonins, cytosolic BBS6 does not oligomerize, and the majority of BBS6 resides within the pericentriolar material (PCM), a proteinaceous tube surrounding centrioles. During interphase, BBS6 is confined to the lateral surfaces of the PCM but during mitosis it relocalizes throughout the PCM and is found at the intercellular bridge. Its predicted substrate-binding apical domain is sufficient for centrosomal association, and several patient-derived mutations in this domain cause mislocalization of BBS6. Consistent with an important centrosomal function, silencing of the BBS6 transcript by RNA interference in different cell types leads to multinucleate and multicentrosomal cells with cytokinesis defects. The restricted tissue distribution of BBS6 further suggests that it may play important roles in ciliated epithelial tissues, which is consistent with the probable functions of BBS proteins in basal bodies (modified centrioles) and cilia. Our findings provide the first insight into the nature and cellular function of BBS6, and shed light on the potential causes of several ailments, including obesity, retinal degeneration, kidney dysfunction and congenital heart disease.
Changing chromatin dynamics and nuclear organization during differentiation inDrosophilalarval tissue
Authors: Thakar Rajika , Csink Amy K.
Published: February 2005

Global changes in gene expression and exit from the cell cycle underlie differentiation. Therefore, understanding chromatin behavior in differentiating nuclei and late G1 is key to understanding this developmental event. A nuclear event that has been shown to specifically occur in late G1 is the association of two heterochromatic blocks in Drosophila. The brownDominant (bwD) chromosome of Drosophila melanogaster contains a large block of heterochromatin near the end of 2R. This distal block associates with centric heterochromatin (2Rh), but not until at least 5 hours into G1. We used the bwD allele as a model for nuclear organization to determine whether its association with the heterochromatic compartment of the second chromosomes (2Rh) strictly requires differentiation or if this change is a stochastic event, its occurrence being proportional to time spent in G1/G0 phase of the cell cycle. Fluorescence in situ hybridization on eye imaginal discs showed increased association between the bw locus and 2Rh in differentiated cells. Interestingly, an increase in the number of nuclei showing bwD-2Rh association in the brains of developmentally delayed larvae that were compromised for differentiation was also observed. Live fluorescence imaging showed that the kinetics of chromatin movement remains unchanged in the developmentally arrested nuclei. These observations suggest that nuclear reorganization is not directly controlled by specific inductive signals during differentiation and that this nuclear reorganization can happen in a cell, regardless of differentiation state, that is arrested in the appropriate cell cycle stage. However, we did see changes that appear to be more directly correlated with differentiation. Dynamic imaging in eye imaginal discs showed that the movement of chromatin is more constrained in differentiated cells, implying that confinement of loci to a smaller nuclear space may help to maintain the changed organization and the transcription profile that accompanies differentiation.
The chemokine SDF-1 differentially regulates axonal elongation and branching in hippocampal neurons
Authors: Pujol Fabien , Kitabgi Patrick , Boudin Hélène
Published: February 2005

Recent data have shown that the chemokine SDF-1 plays a critical role in several aspects of brain development such as cell migration and axon pathfinding. However, its potential function in the generation of axons and dendrites is poorly characterized. In order to better understand the role of SDF-1 in the development of central neurons, we studied the cellular distribution of the SDF-1 receptor CXCR4 by immunocytochemistry of developing hippocampal neurons and tested the effect of SDF-1 in process patterning at the early stages of neuronal development. We found that CXCR4 immunoreactivity undergoes a striking redistribution during development. At the early stages, from day 2 to day 4 in culture, CXCR4 is particularly concentrated at the leading edge of growing neurites. As the cells mature, staining declines at the tip of the processes and becomes more broadly distributed along axons and, to a lesser extent, dendrites. SDF-1 stimulation of neurons at day 1-2 in culture triggers several effects on neuronal morphogenesis. SDF-1 reduces growth cone number and axonal outgrowth but stimulates axonal branching. These latter two effects are not observed in other neurites. This study unravels a new role for SDF-1/CXCR4 in specifying hippocampal neuron morphology by regulating axonal patterning at an early stage of neuronal development.
Glycogen synthase kinase-3β phosphorylation of MAP1B at Ser1260 and Thr1265 is spatially restricted to growing axons
Authors: Trivedi Niraj , Marsh Phil , Goold Robert G. , Wood-Kaczmar Alison , Gordon-Weeks Phillip R.
Published: February 2005

Recent experiments show that the microtubule-associated protein (MAP) 1B is a major phosphorylation substrate for the serine/threonine kinase glycogen synthase kinase-3β (GSK-3β) in differentiating neurons. GSK-3β phosphorylation of MAP1B appears to act as a molecular switch regulating the control that MAP1B exerts on microtubule dynamics in growing axons and growth cones. Maintaining a population of dynamically unstable microtubules in growth cones is important for axon growth and growth cone pathfinding. We have mapped two GSK-3β phosphorylation sites on mouse MAP1B to Ser1260 and Thr1265 using site-directed point mutagenesis of recombinant MAP1B proteins, in vitro kinase assays and phospho-specific antibodies. We raised phospho-specific polyclonal antibodies to these two sites and used them to show that MAP1B is phosphorylated by GSK-3β at Ser1260 and Thr1265 in vivo. We also showed that in the developing nervous system of rat embryos, the expression of GSK-3β phosphorylated MAP1B is spatially restricted to growing axons, in a gradient that is highest distally, despite the expression of MAP1B and GSK-3β throughout the entire neuron. This suggests that there is a mechanism that spatially regulates the GSK-3β phosphorylation of MAP1B in differentiating neurons. Heterologous cell transfection experiments with full-length MAP1B, in which either phosphorylation site was separately mutated to a valine or, in a double mutant, in which both sites were mutated, showed that these GSK-3β phosphorylation sites contribute to the regulation of microtubule dynamics by MAP1B.
Leaf-fiber lignins of Phormium varieties compared bysolid-state 13C NMR spectroscopy
Authors: Newman Roger H. , Tauwhare Stephen E.K. , Scheele Sue , Te Kanawa Rangi
Published: February 2005

Solid-state NMR spectroscopy was used to determine total lignin and to distinguish between the syringyl and guaiacyl components of Phormium leaves. Fibers obtained from the upper (shiny) and lower (dull) surfaces of a P. tenax leaf showed guaiacyl lignin contents of 1.5% and 5.4% by weight, respectively. Guaiacyl lignin is known to have poor photostability, so the analyses supported a traditional view of the upper-surface fibers as the more suitable for textiles. All other analyses involved mixtures of fibers from both upper and lower surfaces. They showed no detectable differences in guaiacyl content between leaves within a ramet, or between ramets in a P. tenax bush, with a mean value of 2.2% for 20 leaves. There were no detectable differences in guaiacyl content between bushes of the variety Taeore grown at different sites, with a mean value of 2.7% for 6 sites. There were detectable differences in guaiacyl content between 15 named varieties grown at a single site, with values as low as 2.3% and as high as 4.5%. Lowest guaiacyl contents were found in varieties traditionally used for textiles. The highest guaiacyl lignin contents, 6.0% and 5.8%, were found in P. cookianum and in a plant grown from stock obtained at Norfolk Island. Syringyl lignin contents were relatively uniform between varieties, with a mean value of 6.7%.
Antioxidant activity of different components of pine species
Authors: Zulaica-Villagomez Hilda , Peterson David M. , Herrin Lauri , Young Raymond A.
Published: February 2005

The total phenolic content and antioxidant activity of extracts from pine species were evaluated for various plant components, with emphasis on the seed cones. Seed cones from pine species were found to contain relatively high amounts of both total phenolics and antioxidant activity, and there appears to be some correlation of the two measurements. Juvenile cones contained by far the highest phenolic and antioxidant activity, but this high activity appears to be related to seeds retained in some of the samples, possibly due to the presence of proteins or additional antioxidants in the seeds. The phenolic content and antioxidant activity were also measured for other plant components and for a few other species for comparison. In general, the cones of red and jack pine exhibited the highest antioxidant activity compared to black and southern pines. The general trend for both total phenolics and antioxidant activity was (highest to lowest): juvenile cones>needles>new cones> bark>old cones>wood. Obviously, cones could represent a viable source of antioxidants, especially compared to the wood of species that had comparatively low activity. Collection and extraction of pine cones for antioxidants would be a non-destructive method for procurement of this medicinal aid.
Three-dimensional visualisation of bacterial decay in individual tracheids of Pinus sylvestris
Authors: Björdal Charlotte , Nilsson Thomas , Bardage Stig
Published: February 2005

Archaeological wood from waterlogged environments is mainly degraded by erosion bacteria. Under the light microscope, a distinct chequered decay pattern is often found in superficially to moderately degraded wood. Serial sections ofPinus sylvestris, degraded by erosion bacteria, were examined to gain an understanding of this phenomenon. An advanced image analysis program was used to transform series of 2-dimensional (2-D) images from attacked fibres into 3-D illustrations in order to visualise variations in decay along 340 μm of the tracheid.

Degradation by erosion bacteria proceeded from the cell lumen into the secondary cell wall. Attack was initiated at several positions in the same tracheid. The chequered pattern observed in transverse sections, often referred to as degraded fibres adjacent to sound ones, shows only the decay status at the section point. A sound cell wall does not necessarily indicate a sound fibre. A fibre in moderately degraded wood often consists of both degraded and sound areas.
Speciation of arsenic and chromium in the leachate from chromated copper arsenate (CCA) type C treated southern pine (Pinus spp.)
Authors: Cui Weining , Flores del Pino Lisveth , Voice Thomas C. , Chou Karen , Pascal Kamdem D.
Published: February 2005

A 558-h laboratory leaching test (AWPA E-11) was carried out on both commercially and laboratory chromated copper arsenate (CCA) type C-treated southern pine. Arsenic, chromium, and copper concentrations in the leachate collected were examined. Leaching of chromium and copper from CCA-treated wood cubes were nearly undetectable using flame atomic absorption spectroscopy after 174 and 366 h, respectively. Less than 10% of the total chromium in the leachate was present as hexavalent chromium [Cr(VI)] after leaching for 30 h. Selective ion-exchange chromatography was used to speciate arsenic in the leachate. In the first 270 h, approximately 70–90% of the total arsenic in the leachate was inorganic pentavalent arsenic [As(V)] and 10–30% was inorganic trivalent arsenic [As(III)].
Comments on the experimental methodology for determination of the hygro-mechanical properties of wood
Authors: Muszyński Lech , Lagana Rastislav , Shaler Stephen M. , Davids William
Published: February 2005

When wood is subjected simultaneously to load and moisture content changes below the fiber saturation point, the mechano-sorptive effect may be observed as an additional deformation that cannot be attributed to simple superposition of elastic deformation, free shrinkage or swelling, or creep in steady climate conditions. The phenomenon has been subject to research for more than half a century. Although numerous mathematical models and detailed theoretical descriptions have been proposed over time, the basic mechanism of mechano-sorption has remained unclear, the experimental data are scattered and lack logical classification, and the experimental determination of its basic parameters on a material level, understood as a local property decoupled from artifacts of the testing protocol, remains a serious challenge. In this paper basic requirements for adequate experimental methods for comprehensive determination of the mechano-sorptive behavior of wood are proposed and briefly discussed. The principal requirements are that the experimental research on mechano-sorption is focused on the material level properties and elementary loading modes (tension and compression); that proper attention is paid to the effect of changing distribution of moisture content within the tested volume; and that the tests are designed so that a comprehensive separation of strain components is enhanced.
Simple and safe production of yttrium-90 from a new type of 90Sr/90Y generator
Authors: Du Jin , Chinol Marco , Savonen Aki , Hiltunen Jukka
Published: February 2005

Yttrium-90 (90Y) has attracted much research attention in targeted radionuclide therapy because its many favorable properties and availability from a long shelf-life generator system. Although numerous generator systems have been developed for the production of 90Y, a common disadvantage is that the 90Y is not eluted in an ionic form suitable for direct labeling of chelating agents bound to useful targeting molecules. In this study, we have adapted previously published procedures and developed a 740 MBq (20 mCi) of generator system in which the parent activity 90Sr was retained on a cation exchange resin, while the daughter 90Y activity was eluted with acetate buffer solution and used directly to label useful radioconjugates without further manipulations. A safety column, not loaded with 90Sr, was connected in series with the generator resulting in an eluate free of any 90Sr breakthrough for at least eight months. The features of this new generator make it suitable for clinical applications.
Transmutation experiments on129I,139La and237Np using the Nuclotron accelerator
Authors: Westmeier Wolfram , Brandt R. , Langrock E.-J. , Robotham H. , Odoj R. , Adam J. , Bradnova V. , Golovatyuk V. M. , Krivopustov M. I. , Sosnin A. N. , Hashemi-Nezhad S. R. , Zamani-Valasiadou M.
Published: February 2005

Transmutation experiments have been carried out using the NUCLOTRON, a new accelerator for relativistic particles. The experiments were carried out in the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna, Russian Federation. Earlier experiments using an 8 cm Ø Pb-target of 20 cm length and surrounded by 6 cm paraffin (GAMMA-2 target) have been continued to study the transmutation of139La and the highly radiotoxic radwaste nuclides129I and237Np using spallation neutrons produced by relativistic protons with energies 0.5 GeV ≤Ep≤ 4.15 GeV. Results of previous experiments were complemented with additional results, thus yielding data systematics with small uncertainties over the probably commercially relevant energy range of 0.5 GeV ≤Ep≤ 1.0 GeV and also in the scientifically interesting range above 1 GeV. Moreover, neutron density distributions in irradiations with 0.65 GeV, 1 GeV and 3.7 GeV protons were determined on the surface of the paraffin moderator for two energy regimes of slow and intermediate/fast neutrons. A large set of high quality experimental data with small uncertainties has been generated that can serve as benchmark data for modelling purposes.
Laboring under Uncertainty: Identity Renegotiation among Contingent Workers
Authors: Padavic Irene
Published: February 2005

Relying on interviews with contingent workers in diverse jobs, this article explores the motivations underlying worker consent, in particular, workers' commitment to employers who did little to encourage it. Driven by the need to address the “spoiled identity” problem brought on by contingent employment, workers engaged in identity‐management strategies that included the following: defining a willingness to work hard rather than the job per se as determinative of personal value, asserting an alternative vocation as one's appropriate identity‐conferring occupation, and aligning with managers as a reference group. These strategies had the ideological effect of reaffirming a managerial ideology that hampered the ability to formulate a critique of existing employment relations. A much smaller group, made up of disillusioned day laborers with few illusions about middle‐class respectability, rejected identity‐management strategies and regarded their relationship with employers in the purely instrumental terms that the business press assumes would apply to all workers. The article concludes that cultural lag and the raw appeal of the notion of a caring employer may underlie the persistence of the accommodationist orientations displayed by most of these workers.
Recombination in a male carrier of two reciprocal translocations involving chromosomes 14, 14′, 15, and 21 leading to balanced and unbalanced rearrangements in offspring
Authors: Soler Anna , Sánchez Aurora , Carrió Ana , Badenas Cèlia , Milà Montserrat , Margarit Ester , Borrell Antoni
Published: February 2005

We report an unusual case of a familial complex chromosome rearrangement (CCR), ascertained through prenatal diagnosis. The fetus carried an apparently balanced CCR with a recombinant 3‐segment chromosome derived from two paternal reciprocal translocations involving both homologs of chromosome 14 and chromosomes 15 and 21, respectively. A probably normal phenotype was predicted and confirmed after birth. His older sister carried an unbalanced karyotype with partial trisomy 14 and partial monosomy 21, and displayed an apparently normal, paternally derived chromosome 14 that resulted from recombination between two derivative chromosomes. Fluorescent in situ hybridization (FISH) and molecular studies were essential for the characterization of the rearrangement. The “rebuilding,” through recombination, of a chromosome involved in two different translocations in a progenitor, was demonstrated for the first time by molecular analysis. Our family is another good example of how balanced familial complex translocations are in a state of flux and can change from one generation to the next. © 2005 Wiley‐Liss, Inc.