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1

Effects of placing micro-implants of melatonin in the pars tuberalis, pars distalis and the lateral septum of the forebrain on the secretion of FSH and prolactin, and testicular size in rams.  

PubMed

Previous studies involving the placement of microimplants of melatonin in the brain in sheep exposed to long days have provided evidence that melatonin acts within or close to the mediobasal hypothalamus (MBH) to mediate the effects of daylength on cycles in reproduction, moulting and other seasonal characteristics. To extend these observations, groups of Soay rams have now been treated with micro-implants of melatonin placed in the pars tuberalis (PT) and pars distalis (PD) of the pituitary gland, and in the lateral septum of the forebrain (septum). The PT and septum are potential target sites for the action of melatonin based on the localized binding of iodomelatonin assessed by in situ autoradiography. The animals were initially exposed to alternating 16-week periods of long days (16 h light: 8 h darkness; 16L:8D) and short days (8L:16D) to entrain the seasonal cycles. The treatments were started at 10 weeks into a period of long days when the animals had a physiology normally observed in summer (low blood plasma concentrations of FSH and high concentrations of prolactin), and they remained under long days throughout the experiments. In experiment 1, animals received micro-implants of melatonin placed in the PT (n = 6) or PD (n = 4), or received empty implants in similar sites (n = 4) or no surgery (n = 4; total control, n = 8). In experiment 2, groups of animals received microimplants of melatonin placed in the lateral septum (septum, n = 7) or received corresponding control treatments (total control, n = 8). The micro-implants consisted of 22 gauge stainless-steel needles with melatonin fused inside the tip. They were inserted bilaterally in the selected sites and left in place for 14 weeks. The biological effects of the treatments were assessed by measuring the changes in the blood plasma concentrations of FSH and prolactin, growth of the teses and moulting of the pelage over a period of 28 weeks (14 weeks treatment and 14 weeks post-treatment). The administration of melatonin in the PT, but not in the PD or septum, affected the photoperiodically induced cycle in the secretion of FSH and prolactin. In the PT group there was no significant change in the plasma concentrations of FSH during the treatment with melatonin, but there was a significant (P < 0.001, ANOVA) decrease in the levels of FSH after the treatment associated with premature regression of the testes.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7931000

Lincoln, G A

1994-08-01

2

Pharmacogenetics of FSH action  

PubMed Central

Purpose of the review To review the current knowledge of genetic variants in the two genes affecting the individual responsiveness to follicle-stimulating hormone (FSH) action—the FSH beta-subunit (FSHB) and the FSH receptor (FSHR), as well as the pharmacogenetic ramifications of the findings. Recent findings Four common variants in FSHB/FSHR were shown to exhibit significant effect on FSH action: linked FSHR variants Thr307Ala and Asn680Ser determining common receptorisoforms, andgene expression affecting polymorphisms FSHR –29G/A and FSHB–211G/T. In women, the FSHR Thr307Ala/Asn680Ser polymorphisms show consistent predictive value for estimating the most optimal rFSH dosage in controlled ovarian hyperstimulation(COH).The same variants exhibit a potential for the pharmacogenetic assessment of the treatment ofPCOS. The FSHR–29G/A variant was also shown to contribute to ovarian response to COH. Pilot studies have suggestedthe FSHB–211TT-homozygous oligozoospermicmen with genetically determined low concentration of FSH, as potentially the best responders to FSH treatment; furthermore, modulation of this response by FSHR polymorphisms is possible. Summary Genetic variants in FSHB/FSHRexhibit a potential for pharmacogenetic applications in selecting appropriate treatment options (timing and dosage) in male and female conditions requiring or benefitting from FSH therapy. PMID:22499219

Laan, Maris; Grigorova, Marina; Huhtaniemi, Ilpo T.

2012-01-01

3

A synthetic peptide corresponding to human FSH. beta. -subunit 33-53 binds to FSH receptor, stimulates basal estradiol biosynthesis, and is a partial antagonist of FSH  

SciTech Connect

The authors have previously shown that hFSH-{beta} 34-37 (KTCT) and 49-52 (TRDL) inhibit binding of {sup 125}I-hFSH to FSH receptor in calf testis membranes and that hFSH-{beta} 33-53, which encompasses these tetrapeptides, inhibits binding with increased potency. hFSH-{beta} 33-53 rapidly dimerizes under conditions utilized in the receptor binding assay (pH 7.5) so that the binding inhibition reported earlier was due to the hFSH-{beta} 33-53 dimer rather than the monomer. At pH 6.5, conversion to dimer does not occur, and binding inhibition could be unequivocally attributed to the monomer. Radioiodinated and alkylated hFSH-{beta} 33-53 binds to the FSH receptor. The biological activity of hFSH-{beta} 33-53 was assessed by its ability to affect the conversion of androstenedione to estradiol in rat Sertoli cells cultures. This result demonstrates that the free R-SH group at Cys51 is not responsible for the inhibition. FSH-{beta} 33-53 also significantly stimulated basal levels of estradiol synthesis, but not to maximal levels observed with FSH (partial agonist). Neither the carbohydrate content of hFSH-{beta} nor the {alpha} subunit of FSH appears to be essential for signal transduction and expression of the hormone effect of FSH-{beta} 33-53.

Santa Coloma, T.A.; Dattatreyamurty, B.; Reichert, L.E. Jr. (Albany Medical College, NY (USA))

1990-02-06

4

Follicle-stimulating hormone (FSH) blood test  

MedlinePLUS

... developed In children, FSH is involved with the development of sexual features. The test is ordered for children: Who develop sexual features at a very young age Who are delayed in starting puberty

5

FSH Directly Regulates Bone Mass Yuanzhen Peng,1  

E-print Network

solely to declining estrogen levels. Although FSH levels rise sharply in parallel, a direct effect of FSH, suggesting that the skeletal action of FSH is estrogen independent. Osteoclasts and their precursors possess of breast cancer, stroke, and heart attacks (Stepnick, 2004). The disease results from a disruption

Wisconsin at Madison, University of

6

Sequential protocol with urinary-FSH/recombinant-FSH versus standard protocol with recombinant-FSH in women of advanced age undergoing IVF.  

PubMed

A stimulation protocol mimicking the physiological pattern of FSH release may improve IVF outcome in women of advanced age. Urinary-FSH delivers a wider range of isoforms including the most acidic produced during the early follicular phase when oestradiol level is low, a common condition in women of advanced reproductive age. We hypothesized that a stimulation protocol using urinary-FSH during the early follicular phase and then shifting toward recombinant-FSH may improve oocyte quality and pregnancy rate in 35-40 years old patients in IVF program. A retrospective study was performed: after a standard down-regulation with GnRH-analogue, 115 women underwent stimulation with urinary-FSH for 6 days according to a step-down approach and then shifting to recombinant-FSH (group A), 115 women underwent a stimulation protocol with only recombinant-FSH (group B). Days of stimulation were lower in group A than in group B, a higher proportion of MII oocytes and of grade 1 embryos, higher implantation rate and pregnancy rate were observed in group A versus group B. We conclude that a sequential protocol using urinary-FSH in the early days of stimulation and subsequently recombinant-FSH may improve the IVF outcome in patients of advanced reproductive age. PMID:24948339

Colacurci, Nicola; Caprio, Francesca; La Verde, Eugenio; Trotta, Carlo; Ianniello, Raffaele; Mele, Daniela; De Franciscis, Pasquale

2014-10-01

7

Isoforms and half-life of FSH from sheep with different reproductive states  

Microsoft Academic Search

The glycoprotein hormone FSH comes in many different isoforms. In humans and rats the charges of the FSH isoforms vary with reproductive state and these affect the half-life of FSH in plasma. In this study we examined the charge heterogeneity of FSH in pituitary extracts from sheep with different reproductive states. Also the half-life of clearance of pituitary FSH from

L G Moore; W Ng Chie; N L Hudson; K P McNatty

2000-01-01

8

Spermatid count as a predictor of response to FSH therapy.  

PubMed

This study evaluated the predictive power of spermatid count and cytology for assisted reproduction outcome after FSH therapy. A total of 174 men with severe oligozoospermia and normal plasma FSH concentration underwent semen analysis including spermatid count, TUNEL test, FISH analysis for sperm aneuploidies and testicular fine-needle aspiration cytology. Ninety-two men with hypospermatogenesis received FSH therapy for 3 months and 82 patients with maturative disturbance or partial obstruction served as controls. Semen was analysed at baseline, after FSH therapy and after 3- and 9-month follow up, and pregnancies were recorded. Subjects not reaching pregnancy at 3-month follow up were recommended assisted reproduction treatment. Spermatid count was related to testicular cytology: spermatid concentrations <0.01, 0.01-0.3 and >0.3 × 10(6)/ml were predictive of partial obstruction, hypospermatogenesis and maturative disturbance. FSH therapy patients showed increases in sperm number and motility (both P < 0.001), allowing some couples to undergo intrauterine insemination instead of IVF. Cumulative pregnancy rate after 12 months was higher with FSH therapy (44.6%) than without (22.0%; P = 0.002). FSH therapy improved pregnancy rate and sometimes allowed less invasive assisted reproduction treatment in well-selected patients. Spermatid count could represent a new parameter to predict response to FSH therapy. One-hundred seventy-four patients with severe reduction of sperm count and normal sex hormones plasma levels underwent semen analysis with spermatid count, and testicular fine needle aspiration cytologiy (FNAC). Ninety-two men infertile men with reduced sperm production (hypospermatogenesis) were treated with highly purified urofollitropin and 82 patients with sperm maturative defects or partial obstruction of the seminal tract served as controls. After treatment and after the following 3 and 9 months all subjects performed a new semen analysis and pregnancies were recorded. Subjects who had not reached spontaneous pregnancy were suggested to undergo assisted reproductive techniques (ARTs). Spermatid count was strongly related to testicular cytology: spermatid concentrations were predictive of partial obstruction, hypospermatogenesis and maturative disturbance respectively. Treated patients showed significant increase in sperm number and motility allowing some couples to undergo easier and less invasive assisted reproductive techniques. The number of pregnancies was significantly higher among treated (44.6%) than untreated couples (22.0%). Our data confirmed that FSH treatment can induce a significant improvemet of pergnancy rate and sometimes allows less invasive ARTs use in well selected severe oligozoospermic patients. Moreover, we suggest that spermatid count can be useful to define tubular status and could represent a new parameter to predict response to FSH therapy. PMID:24816256

Garolla, Andrea; Selice, Riccardo; Engl, Bruno; Bertoldo, Alessandro; Menegazzo, Massimo; Finos, Livio; Lenzi, Andrea; Foresta, Carlo

2014-07-01

9

Induction of ovulation in seasonally anestrous mares under ambient lights using recombinant equine FSH (reFSH).  

PubMed

Traditionally, mares are put under artificial lights to advance the first ovulation of the year. The aim of the present study was to determine the efficacy of recombinant equine FSH (reFSH) in stimulating follicular development and advancing the first ovulation of the year in seasonally anestrous mares compared with anestrous mares given a placebo. Both groups of mares were housed under ambient light conditions. Sixty deep anestrous mares of light horse breeds (follicular diameters ? 20 mm in diameter and progesterone <1 ng/mL) were maintained under a natural photoperiod at three different sites: University of California, Davis, Colorado State University, and University of Kentucky Gluck Centre. Twenty mares at each site were randomly allocated to receive either 0.65 mg of reFSH (group A: treatment; n = 10) or a placebo (group B: control; n = 10) twice daily by im beginning on January 31. Treatment continued until one or more preovulatory follicles developed or up to a maximum of 15 days. Randomized treatments were blinded. Follicular development was closely monitored by transrectal ultrasonography. When the largest follicle reached ? 35 mm in diameter, reFSH treatment was discontinued and an injection of 2500 international units of hCG was administered iv 36 hours later to induce ovulation. Jugular blood samples were collected daily from all mares at University of California, Davis, and processed for LH, FSH, progesterone, estradiol-17?, and immunoreactive-inhibin by RIA. All 30 mares receiving reFSH (group A) developed follicles ? 35 mm within 7.4 ± 1.6 days of treatment. Twenty-three of the 30 reFSH-treated mares (group A) ovulated within 72 hours after hCG administration. In contrast, mares in group B (placebo, control) did not exhibit significant follicular development and none ovulated within the 15-day observation period. Mares in group A had significantly higher plasma levels of FSH, estradiol-17?, and immunoreactive-inhibin during treatment but did not exhibit a preovulatory LH surge. Mares administered reFSH returned to anestrus and spontaneously ovulated at a similar calendar date as control mares. These data indicate that reFSH was effective in stimulating the development of ovarian follicles and advancing the first ovulation of the year in seasonally anestrous mares under ambient lights but was not successful in inducing continued cyclicity. PMID:23768752

Meyers-Brown, Geraldine A; McCue, Patrick M; Troedsson, Mats H T; Klein, Claudia; Zent, Walter; Ferris, Ryan A; Lindholm, Alicia R G; Scofield, David B; Claes, Anthony N; Morganti, Monica; Colgin, Mark A; Wetzel, Robert L; Peters, Andrew R; Roser, Janet F

2013-09-15

10

Effects of FSH and testosterone on Sertoli cells and spermatocytes from rat testis  

E-print Network

Effects of FSH and testosterone on Sertoli cells and spermatocytes from rat testis F. F. G was stimulated in the presence of testosterone, FSH or dibutyryl cAMP. In addition Sertoli cells appeared observations support the view that the effects of follitropin (FSH) and testosterone on germinal cells might

Paris-Sud XI, Université de

11

Produção de L-asparaginase II recombinante de Erwinia carotovora em cultivos de Escherichia coli em batelada alimentada.  

E-print Network

??Biofármacos são, na sua maioria, proteínas recombinantes produzidas por ferramentas biotecnológicas. Preparações de L-asparaginase que atualmente estão no mercado, derivadas de Escherichia coli ou Eravinia… (more)

Gustavo Roth

2012-01-01

12

GRK-6 mediates FSH action synergistically enhanced by estrogen and the oocyte in rat granulosa cells.  

PubMed

Estrogen is known to play a pivotal role in granulosa cell responses to follicle-stimulating hormone (FSH) that is critical for the establishment of dominant follicles and subsequent ovulation in mammals. Thus, elucidating the cellular and molecular mechanisms that regulate FSH activity is important to understand female fertility. We previously discovered that the oocyte is required for estrogen to exert its positive effects on FSH activity in rat granulosa cells. This finding supports the new concept that estrogen action in granulosa cells is mediated by the oocyte. In the current study, we explored the underlying mechanism. In the presence of oocytes, estrogens enhanced FSH-induced increases in aromatase, steroidogenic acute regulatory protein and FSH receptor mRNA expression as well as cAMP production. However, as forskolin did not mimic FSH activity this indicated that coexistence of estrogen/oocytes increases FSH activity at a site upstream of adenylate cyclase in granulosa cells. We therefore sought a possible involvement of the autoregulatory molecules for FSH receptor, G protein-coupled receptor kinases (GRKs) and ß-arrestins in enhancing FSH activity in response to the estrogen/oocyte co-treatment in granulosa cells. Among the seven known GRK and two ß-arrestin molecules, we found that estrogens with oocytes suppressed FSH-induced GRK-6 mRNA expression. Consistent with this finding, transfecting granulosa cells with small interfering RNA of GRK-6 significantly increased FSH induction of aromatase mRNA, suggesting that endogenous GRK-6 plays an inhibitory role in FSH-induced aromatase mRNA expression. Consequently, these findings strongly suggest that GRK-6 is involved in the mechanism by which estrogen and oocytes synergistically augment FSH activity in granulosa cells. PMID:23583200

Miyoshi, Tomoko; Otsuka, Fumio; Shimasaki, Shunichi

2013-05-01

13

Fsh Controls Gene Expression in Fish both Independently of and through Steroid Mediation  

PubMed Central

The mechanisms and the mediators relaying Fsh action on testicular functions are poorly understood. Unlike in mammals, in fish both gonadotropins (Fsh and Lh) are able to efficiently stimulate steroidogenesis, likely through a direct interaction with their cognate receptors present on the Leydig cells. In this context, it is crucial to understand if Fsh effects are mediated through the production of steroids. To address this issue we performed transcriptome studies after in vitro incubations of rainbow trout testis explants in the presence of Fsh alone or in combination with trilostane, an inhibitor of ?4- steroidogenesis. Trilostane significantly reduced or suppressed the response of many genes to Fsh (like wisp1, testis gapdhs, cldn11, inha, vt1 or dmrt1) showing that, in fish, important aspects of Fsh action follow indirect pathways and require the production of ?4-steroids. What is more, most of the genes regulated by Fsh through steroid mediation were similarly regulated by Lh (and/or androgens). In contrast, the response to Fsh of other genes was not suppressed in the presence of trilostane. These latter included genes encoding for anti-mullerian hormone, midkine a (pleiotrophin related), angiopoietine-related protein, cyclins E1 and G1, hepatocyte growth factor activator, insulin-like growth factor 1b/3. A majority of those genes were preferentially regulated by Fsh, when compared to Lh, suggesting that specific regulatory effects of Fsh did not depend on steroid production. Finally, antagonistic effects between Fsh and steroids were found, in particular for genes encoding key factors of steroidogenesis (star, hsd3b1, cyp11b2-2) or for genes of the Igf system (igf1b/3). Our study provides the first clear evidence that, in fish, Fsh exerts ?4-steroid-independent regulatory functions on many genes which are highly relevant for the onset of spermatogenesis. PMID:24194844

Sambroni, Elisabeth; Lareyre, Jean-Jacques; Le Gac, Florence

2013-01-01

14

Fsh controls gene expression in fish both independently of and through steroid mediation.  

PubMed

The mechanisms and the mediators relaying Fsh action on testicular functions are poorly understood. Unlike in mammals, in fish both gonadotropins (Fsh and Lh) are able to efficiently stimulate steroidogenesis, likely through a direct interaction with their cognate receptors present on the Leydig cells. In this context, it is crucial to understand if Fsh effects are mediated through the production of steroids. To address this issue we performed transcriptome studies after in vitro incubations of rainbow trout testis explants in the presence of Fsh alone or in combination with trilostane, an inhibitor of ?4- steroidogenesis. Trilostane significantly reduced or suppressed the response of many genes to Fsh (like wisp1, testis gapdhs, cldn11, inha, vt1 or dmrt1) showing that, in fish, important aspects of Fsh action follow indirect pathways and require the production of ?4-steroids. What is more, most of the genes regulated by Fsh through steroid mediation were similarly regulated by Lh (and/or androgens). In contrast, the response to Fsh of other genes was not suppressed in the presence of trilostane. These latter included genes encoding for anti-mullerian hormone, midkine a (pleiotrophin related), angiopoietine-related protein, cyclins E1 and G1, hepatocyte growth factor activator, insulin-like growth factor 1b/3. A majority of those genes were preferentially regulated by Fsh, when compared to Lh, suggesting that specific regulatory effects of Fsh did not depend on steroid production. Finally, antagonistic effects between Fsh and steroids were found, in particular for genes encoding key factors of steroidogenesis (star, hsd3b1, cyp11b2-2) or for genes of the Igf system (igf1b/3). Our study provides the first clear evidence that, in fish, Fsh exerts ?4-steroid-independent regulatory functions on many genes which are highly relevant for the onset of spermatogenesis. PMID:24194844

Sambroni, Elisabeth; Lareyre, Jean-Jacques; Le Gac, Florence

2013-01-01

15

Elevated basal FSH and embryo quality: lessons from extended culture embryos  

Microsoft Academic Search

Background  The relationship between elevated basal FSH and embryo quality remains a topic of heated discussion among practitioners of\\u000a ART. Some authors suggest a negative effect of raised FSH on the quality of embryos and therefore on IVF treatment outcome.\\u000a We postulate that women with elevated FSH who respond well to ovarian stimulation and have embryos to transfer, have the same

MY Thum; E Kalu; H Abdalla

2009-01-01

16

Role of anti-Müllerian hormone and bone morphogenetic proteins in the regulation of FSH sensitivity.  

PubMed

The ovary is under control of the hypothalamus and pituitary through the glycoprotein hormones LH and FSH. These hormones undergo a cyclic variation which results in the selection of the species-specific number of follicles that will ovulate during the cycle. Where LH is the main ovulatory hormone and regulator of corpus luteum function, FSH plays an essential role in the cyclic recruitment of the follicles. Within the microenvironment of the ovary, growth factors affect this dominant control of FSH by regulating the FSH sensitivity of individual follicles. In this review we discuss the role of anti-Müllerian hormone (AMH) and bone morphogenetic proteins (BMPs) in this process. PMID:23994017

Visser, Jenny A; Themmen, Axel P N

2014-01-25

17

Follicle stimulating hormone modulates ovarian stem cells through alternately spliced receptor variant FSH-R3  

PubMed Central

Background We have earlier reported that follicle stimulating hormone (FSH) modulates ovarian stem cells which include pluripotent, very small embryonic-like stem cells (VSELs) and their immediate descendants ‘progenitors’ termed ovarian germ stem cells (OGSCs), lodged in adult mammalian ovarian surface epithelium (OSE). FSH may exert pleiotropic actions through its alternatively spliced receptor isoforms. Four isoforms of FSH receptors (FSHR) are reported in literature of which FSH-R1 and FSH-R3 have biological activity. Present study was undertaken to identify FSHR isoforms mediating FSH action on ovarian stem cells, using sheep OSE cells culture as the study model. Methods Cultures of sheep OSE cells (a mix of epithelial cells, VSELs, OGSCs and few contaminating red blood cells) were established with and without FSH 5IU/ml treatment. Effect of FSH treatment on self-renewal of VSELs and their differentiation into OGSCs was studied after 15 hrs by qRT-PCR using markers specific for VSELs (Oct-4A, Sox-2) and OGSCs (Oct-4). FSH receptors and its specific transcripts (R1 and R3) were studied after 3 and 15 hrs of FSH treatment by immunolocalization, in situ hybridization and qRT-PCR. FSHR and OCT-4 were also immuno-localized on sheep ovarian sections, in vitro matured follicles and early embryos. Results FSH treatment resulted in increased stem cells self-renewal and clonal expansion evident by the appearance of stem cell clusters. FSH receptors were expressed on ovarian stem cells whereas the epithelial cells were distinctly negative. An increase in R3 mRNA transcripts was noted after 3 hrs of FSH treatment and was reduced to basal levels by 15 hrs, whereas R1 transcript expression remained unaffected. Both FSHR and OCT-4 were immuno-localized in nuclei of stem cells, showed nuclear or ooplasmic localization in oocytes of primordial follicles and in cytoplasm of granulosa cells in growing follicles. Conclusions FSH modulates ovarian stem cells via FSH-R3 to undergo potential self-renewal, clonal expansion as ‘cysts’ and differentiation into oocytes. OCT-4 and FSHR proteins (required initially to maintain pluripotent state of VSELs and for FSH action respectively) gradually shift from nuclei to cytoplasm of developing oocytes and are later possibly removed by surrounding granulosa cells as the oocyte prepares itself for fertilization. PMID:23870332

2013-01-01

18

Pars Stress Fracture (Lumbar Spondylolysis)  

MedlinePLUS

... Neck and Back) > Pars Stress Fracture Pars Stress Fracture Page Content Pars stress fractures occur in young athletes involved in repetitive bending ... an episode of low back pain Pars stress fracture, also called lumbar spondylolysis, is one of the ...

19

Immunization with FSH? fusion protein antigen prevents bone loss in a rat ovariectomy-induced osteoporosis model  

SciTech Connect

Highlights: •A GST-FSH fusion protein was successfully expressed in E. coli. •Immunization with GST-FSH antigen can raise high-titer anti-FSH polyclonal sera. •Anti-FSH polyclonal sera can neutralize osteoclastogenic effect of FSH in vitro. •FSH immunization can prevent bone loss in a rat osteoporosis model. -- Abstract: Osteoporosis, a metabolic bone disease, threatens postmenopausal women globally. Hormone replacement therapy (HTR), especially estrogen replacement therapy (ERT), is used widely in the clinic because it has been generally accepted that postmenopausal osteoporosis is caused by estrogen deficiency. However, hypogonadal ? and ? estrogen receptor null mice were only mildly osteopenic, and mice with either receptor deleted had normal bone mass, indicating that estrogen may not be the only mediator that induces osteoporosis. Recently, follicle-stimulating hormone (FSH), the serum concentration of which increases from the very beginning of menopause, has been found to play a key role in postmenopausal osteoporosis by promoting osteoclastogenesis. In this article, we confirmed that exogenous FSH can enhance osteoclast differentiation in vitro and that this effect can be neutralized by either an anti-FSH monoclonal antibody or anti-FSH polyclonal sera raised by immunizing animals with a recombinant GST-FSH? fusion protein antigen. Moreover, immunizing ovariectomized rats with the GST-FSH? antigen does significantly prevent trabecular bone loss and thereby enhance the bone strength, indicating that a FSH-based vaccine may be a promising therapeutic strategy to slow down bone loss in postmenopausal women.

Geng, Wenxin; Yan, Xingrong; Du, Huicong; Cui, Jihong; Li, Liwen, E-mail: liven@nwu.edu.cn; Chen, Fulin, E-mail: chenfl@nwu.edu.cn

2013-05-03

20

Fsh Controls Gene Expression in Fish both Independently of and through Steroid Mediation  

E-print Network

gonadotropins (Fsh and Lh) are able to efficiently stimulate steroidogenesis, likely through a direct or suppressed the response of many genes to Fsh (like wisp1, testis gapdhs, cldn11, inha, vt1 or dmrt1) showing was not suppressed in the presence of trilostane. These latter included genes encoding for anti-mullerian hormone

Paris-Sud XI, Université de

21

An economic evaluation of highly purified HMG and recombinant FSH based on a large randomized trial  

Microsoft Academic Search

Public funding for IVF is increasingly being challenged by health authorities in an attempt to minimize health service costs. In light of treatment rationing, the need to consider costs in relation to outcomes is paramount. To assess the cost implications of gonadotrophin treatment options, an economic evaluation comparing highly purified human menopausal gonadotrophin (HP-HMG) and recombinant FSH (rFSH) has been

Jaroslaw Wechowski; Mark Connolly; Philip McEwan; Richard Kennedy

2007-01-01

22

Predicting ongoing pregnancy following ovulation induction with recombinant FSH in women with polycystic ovary syndrome  

Microsoft Academic Search

BACKGROUND: Ovulation induction with recombinant FSH (rFSH) is common in women with polycystic ovary syndrome (PCOS) not responding to clomiphene citrate treatment, despite the associated risk of multiple pregnan- cies. We analysed clinical, ultrasonographic and endocrine parameters during initial screening of women with clomiphene citrate-resistant PCOS as predictors of ongoing pregnancy within 12 months of treatment following ovulation induction with

Madelon van Wely; Neriman Bayram; Fulco van der Veen; Patrick M. M. Bossuyt

2005-01-01

23

Chromatofocusing fails to separate hFSH isoforms on the basis of glycan structure.  

PubMed

Follicle-stimulating hormone (FSH) glycosylation is regulated by feedback from the gonads, resulting in an array of glycans associated with FSH preparations derived from pools of pituitary or urine extracts. FSH glycosylation varies due to inhibition of FSHbeta N-glycosylation, elaboration of 1-4 branches possessed by mature N-glycans, and the number and linkage of terminal sialic acid residues. To characterize FSH glycosylation, FSH isoforms in pituitary gland extracts and a variety of physiological fluids are commonly separated by chromatofocusing. Variations in the ratios of immunological and biological activities in the resulting FSH isoform preparations are generally attributed to changes in glycosylation, which are most often defined in terms of sialic acid content. Using Western blotting to assess human FSHbeta glycosylation inhibition revealed 30-47% nonglycosylated hFSHbeta associated with four of six hFSH isoform preparations derived by chromatofocusing. Glycopeptide mass spectrometry assessment of glycan branching in these isoforms extensively characterized two N-glycosylation sites, one at alphaAsn52, the critical glycan for FSH function, and the other at betaAsn24. With two to four N-glycans per FSH molecule, many combinations of charges distributed over these sites can provide the same isoelectric point. Indeed, several glycans were common to all isoform fractions that were analyzed. There was no trend showing predominantly monoantennary glycans associated with the high-pI fractions, nor were predominantly tri- and tetra-antennary glycans associated with low-pI fractions. Thus, differences in receptor binding activity could not be associated with any specific glycan type or location in the hormone. FSH aggregation was associated with reduced receptor binding activity but did not affect immunological activity. However, as gel filtration indicated sufficient heterodimer was present in each isoform preparation to generate complete inhibition curves, the near total loss of receptor binding activity in several preparations could not be explained by aggregation alone, and the mechanism remains unknown. PMID:18197704

Bousfield, George R; Butnev, Vladimir Y; Bidart, Jean-Michel; Dalpathado, Dilusha; Irungu, Janet; Desaire, Heather

2008-02-12

24

Synthetic peptides corresponding to human follicle-stimulating hormone (hFSH)-beta-(1-15) and hFSH-beta-(51-65) induce uptake of 45Ca++ by liposomes: evidence for calcium-conducting transmembrane channel formation  

SciTech Connect

We have previously described FSH receptor-mediated influx of 45Ca++ in cultured Sertoli cells from immature rats and receptor-enriched proteoliposomes via activation of voltage-sensitive and voltage-independent calcium channels. We have further shown that this effect of FSH does not require cholera toxin- or pertussis toxin-sensitive guanine nucleotide binding protein or activation of adenylate cyclase. In the present study, we have identified regions of human FSH-beta-subunit which appear to be involved in mediating calcium influx. We screened 11 overlapping peptide amides representing the entire primary structure of hFSH-beta-subunit for their effects on 45Ca++ flux in FSH receptor-enriched proteoliposomes. hFSH-beta-(1-15) and hFSH-beta-(51-65) induced uptake of 45Ca++ in a concentration-related manner. This effect of hFSH-beta-(1-15) and hFSH-beta-(51-65) was also observed in liposomes lacking incorporated FSH receptor. Reducing membrane fluidity by incubating liposomes (containing no receptor) with hFSH-beta-(1-15) or hFSH-beta-(51-65) at temperatures lower than the transition temperatures of their constituent phospholipids resulted in no significant (P greater than 0.05) difference in 45Ca++ uptake. The effectiveness of the calcium ionophore A23187, however, was abolished. Ruthenium red, a voltage-independent calcium channel antagonist, was able to completely block uptake of 45Ca++ induced by hFSH-beta-(1-15) and hFSH-beta-(51-65) whereas nifedipine, a calcium channel blocker specific for L-type voltage-sensitive calcium channels, was without effect. These results suggest that in addition to its effect on voltage-sensitive calcium channel activity, interaction of FSH with its receptor may induce formation of transmembrane aqueous channels which also facilitate influx of extracellular calcium.

Grasso, P.; Santa-Coloma, T.A.; Reichert, L.E. Jr. (Department of Biochemistry, Albany Medical College, New York, NY (USA))

1991-06-01

25

Single nucleotide polymorphism of FSH? gene associated with reproductive traits in Japanese flounder ( Paralichthys olivaceus)  

NASA Astrophysics Data System (ADS)

Follicle stimulating hormone ? (FSH?) of Japanese flounder ( Paralichthys olivaceus) plays a key role in the regulation of gonadal development. This study aimed to investigate molecular genetic characteristics of the FSH? gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of FSH? on reproductive traits in Japanese flounder. We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the FSH? gene in 60 individuals. We identified only an SNP (T/C) in the coding region of exon3 of FSH?. The SNP (T/C) did not lead to amino acid changes at the position 340 bp of FSH? gene. Statistical analysis showed that the SNP was significantly associated with testosterone (T) level and gonadosomatic index (GSI) ( P < 0.05). Individuals with genotype TC of the SNP had significantly higher serum T levels and GSI ( P < 0.05) than that of genotype CC. Therefore, FSH? gene could be a useful molecular marker in selection for prominent reproductive trait in Japanese Flounder.

He, Feng; Wen, Haishen; Yu, Dahui; Li, Jifang; Shi, Bao; Chen, Caifang; Zhang, Jiaren; Jin, Guoxiong; Chen, Xiaoyan; Shi, Dan; Yang, Yanping

2010-12-01

26

Impaired Fertility and FSH Synthesis in Gonadotrope-Specific Foxl2 Knockout Mice  

PubMed Central

Impairments in pituitary FSH synthesis or action cause infertility. However, causes of FSH dysregulation are poorly described, in part because of our incomplete understanding of mechanisms controlling FSH synthesis. Previously, we discovered a critical role for forkhead protein L2 (FOXL2) in activin-stimulated FSH ?-subunit (Fshb) transcription in immortalized cells in vitro. Here, we tested the hypothesis that FOXL2 is required for FSH synthesis in vivo. Using a Cre/lox approach, we selectively ablated Foxl2 in murine anterior pituitary gonadotrope cells. Conditional knockout (cKO) mice developed overtly normally but were subfertile in adulthood. Testis size and spermatogenesis were significantly impaired in cKO males. cKO females exhibited reduced ovarian weight and ovulated fewer oocytes in natural estrous cycles compared with controls. In contrast, ovaries of juvenile cKO females showed normal responses to exogenous gonadotropin stimulation. Both male and female cKO mice were FSH deficient, secondary to diminished pituitary Fshb mRNA production. Basal and activin-stimulated Fshb expression was similarly impaired in Foxl2 depleted primary pituitary cultures. Collectively, these data definitively establish FOXL2 as the first identified gonadotrope-restricted transcription factor required for selective FSH synthesis in vivo. PMID:23340250

Tran, Stella; Zhou, Xiang; Lafleur, Christine; Calderon, Michael J.; Ellsworth, Buffy S.; Kimmins, Sarah; Boehm, Ulrich; Treier, Mathias; Boerboom, Derek

2013-01-01

27

LH (as HCG) and FSH surges for final oocyte maturation: sometimes it takes two to tango?  

PubMed

Until now, clinicians have been relying solely on LH activity-dependent triggering of final oocyte maturation and thus taken it for granted that the natural midcycle FSH surge is biologically redundant. However, it is time to question this paradigm. Evidence from clinical studies hint that in a yet-to-be-defined subset of patients, dual LH and FSH surge is advantageous compared with LH-only surge in the form of human chorionic gonadotrophin (HCG) trigger. Dual surge can be triggered by a bolus of gonadotrophin-releasing hormone agonist causing a flare-up of both endogenous LH and FSH, resembling the natural midcycle surge of gonadotrophins. HCG given in parallel secures adequate exposure to LH activity. Further research is needed to characterize the patients in whom FSH surge is needed for proper resumption of the oocyte meiotic process. PMID:20851052

Kol, Shahar; Humaidan, Peter

2010-11-01

28

Biological activities of recombinant Manchurian trout FSH and LH: their receptor specificity, steroidogenic and vitellogenic potencies.  

PubMed

Gonadotropins (GTHs), FSH and LH, play central roles in vertebrate reproduction. Here, we report the production of biologically-active recombinant FSH (r-mtFSH) and LH (r-mtLH) of an endangered salmon species, Manchurian trout (Brachymystax lenok), by baculovirus in silkworm (Bombyx mori) larvae. The biological activities of the recombinant hormones were analyzed using COS-7 cell line transiently expressing either amago salmon FSH or LH receptor. The steroidogenic potency of the r-mtFSH and r-mtLH was examined by a culture system using rainbow trout follicles in vitro. In vivo, bioactivity was assessed by measuring ovarian weight, oocyte diameter, and plasma steroid hormone levels in female rainbow trout. Moreover, inducing potency of milt production were examined in vivo using goldfish. Our results demonstrated that the r-mtFSH and r-mtLH were successfully produced in the baculovirus-silkworm system and recognized by their cognate receptors specifically in vitro. The production of estradiol-17beta (E2) and testosterone (T) was stimulated by the r-mtFSH and r-mtLH respectively, from the full-grown follicles of rainbow trout, whereas both E2 and T were increased by relatively higher doses of the recombinant hormones from the follicles of the maturing stage. In in vivo assay, injection of the r-mtFSH but not r-mtLH increased ovarian weight, oocyte diameter, and plasma E2 levels in immature rainbow trout. Injection of both r-mtFSH and r-mtLH induced milt production in male goldfish. In conclusion, the present study strongly suggests that the r-mtFSH and r-mtLH have distinct biological properties, such as a specific responsiveness for the cognate receptor, steroidogenic, and vitellogenic activities for ovarian follicles in salmonids. These recombinant FSH and LH may be applied for future studies on the gonadal development and maturation in fishes as well as the endangered salmon species. PMID:17242173

Ko, Hyeyeon; Park, WooDong; Kim, Dae-Jung; Kobayashi, Makito; Sohn, Young Chang

2007-02-01

29

Redirecting intracellular trafficking and the secretion pattern of FSH dramatically enhances ovarian function in mice  

PubMed Central

FSH and luteinizing hormone (LH) are secreted constitutively or in pulses, respectively, from pituitary gonadotropes in many vertebrates, and regulate ovarian function. The molecular basis for this evolutionarily conserved gonadotropin-specific secretion pattern is not understood. Here, we show that the carboxyterminal heptapeptide in LH is a gonadotropin-sorting determinant in vivo that directs pulsatile secretion. FSH containing this heptapeptide enters the regulated pathway in gonadotropes of transgenic mice, and is released in response to gonadotropin-releasing hormone, similar to LH. FSH released from the LH secretory pathway rescued ovarian defects in Fshb-null mice as efficiently as constitutively secreted FSH. Interestingly, the rerouted FSH enhanced ovarian follicle survival, caused a dramatic increase in number of ovulations, and prolonged female reproductive lifespan. Furthermore, the rerouted FSH vastly improved the in vivo fertilization competency of eggs, their subsequent development in vitro and when transplanted, the ability to produce offspring. Our study demonstrates the feasibility to fine-tune the target tissue responses by modifying the intracellular trafficking and secretory fate of a pituitary trophic hormone. The approach to interconvert the secretory fate of proteins in vivo has pathophysiological significance, and could explain the etiology of several hormone hyperstimulation and resistance syndromes. PMID:24706813

Wang, Huizhen; Larson, Melissa; Jablonka-Shariff, Albina; Pearl, Christopher A.; Miller, William L.; Conn, P. Michael; Boime, Irving; Kumar, T. Rajendra

2014-01-01

30

Developmentally distinct in vivo effects of FSH on proliferation and apoptosis during testis maturation.  

PubMed

The critical influence of follicle stimulating hormone (FSH) on male fertility relates both to its impact on Sertoli cell proliferation in perinatal life and to its influence on the synthesis of Sertoli cell-derived products essential for germ cell survival and function in the developing adult testis. The nature and timing of this shift of germ cells to their reliance on specific Sertoli cell-derived products are not defined. Based on existing data, it is apparent that the dominant function of FSH shifts between 9 and 18 day postpartum (dpp) during the first wave of spermatogenesis from driving Sertoli cell proliferation to support germ cells. To enable comprehensive analysis of the impact of acute in vivo FSH suppression on Sertoli and germ cell development, FSH was selectively suppressed in Sprague-Dawley rats by passive immunisation for 2 days and/or 4 days prior to testis collection at 3, 9 and 18 dpp. The 3 dpp samples displayed no measurable changes, while 4 days of FSH suppression decreased Sertoli cell proliferation and numbers in 9 dpp, but not 18 dpp, animals. In contrast, germ cell numbers were unaffected at 9 dpp but decreased at 18 dpp following FSH suppression, with a corresponding increase in germ cell apoptosis measured at 18 dpp. Sixty transcripts were measured as changed at 18 dpp in response to 4 days of FSH suppression, as assessed using Affymetrix microarrays. Some of these are known as Sertoli cell-derived FSH-responsive genes (e.g. StAR, cathepsin L, insulin-like growth factor binding protein-3), while others encode proteins involved in cell cycle and survival regulation (e.g. cyclin D1, scavenger receptor class B 1). These data demonstrate that FSH differentially affects Sertoli and germ cells in an age-dependent manner in vivo, promoting Sertoli cell mitosis at day 9, and supporting germ cell viability at day 18. This model has enabled identification of candidate genes that contribute to the FSH-mediated pathway by which Sertoli cells support germ cells. PMID:16135663

Meachem, Sarah J; Ruwanpura, Saleela M; Ziolkowski, Jessica; Ague, Jacquelyn M; Skinner, Michael K; Loveland, Kate L

2005-09-01

31

Single-Chain Bifunctional Vascular Endothelial Growth Factor (VEGF)-Follicle-Stimulating Hormone (FSH)-C-Terminal Peptide (CTP) Is Superior to the Combination Therapy of Recombinant VEGF plus FSH-CTP in Stimulating Angiogenesis during Ovarian Folliculogenesis  

Microsoft Academic Search

Infertility technologies often employ exogenous gonadotro- pin therapy to increase antral follicle production. In an effort to enhance ovarian response, several long-acting FSH thera- pies have been developed including an FSH-C-terminal pep- tide (CTP), where the FSH subunits are linked by the CTP moiety from human chorionic gonadotropin, which is respon- sible for the increased half-life of human chorionic gonado-

Rhonda K. Trousdale; Susan V. Pollak; Jeffrey Klein; Leslie Lobel; Yasuhiro Funahashi; Nikki Feirt; Joyce W. Lustbader

2006-01-01

32

Single-chain bifunctional vascular endothelial growth factor (VEGF)-follicle-stimulating hormone (FSH)-C-terminal peptide (CTP) is superior to the combination therapy of recombinant VEGF plus FSH-CTP in stimulating angiogenesis during ovarian folliculogenesis.  

PubMed

Infertility technologies often employ exogenous gonadotropin therapy to increase antral follicle production. In an effort to enhance ovarian response, several long-acting FSH therapies have been developed including an FSH-C-terminal peptide (CTP), where the FSH subunits are linked by the CTP moiety from human chorionic gonadotropin, which is responsible for the increased half-life of human chorionic gonadotropin. We found that administration of FSH-CTP for ovarian hyperstimulation in rats blunted ovarian follicle vascular development. In women, reduced ovarian vasculature has been associated with lower pregnancy rates. We were interested in determining whether vascular endothelial growth factor (VEGF) therapy could enhance ovarian angiogenesis in FSH-CTP-treated rats. Coadministration of systemic FSH-CTP plus recombinant VEGF was compared with treatment with a novel, single-chain bifunctional VEGF-FSH-CTP (VFC) analog. For VFC, the FSH portion targets the protein to the ovary and stimulates follicle growth, whereas VEGF enhances local vascular development. Both in vitro and in vivo studies confirm the dual FSH and VEGF action of the VFC protein. Evaluation of ovarian follicle development demonstrates that administration of combination therapy using VEGF and FSH-CTP failed to increase follicle vasculature above levels seen with FSH-CTP monotherapy. However, treatment with VFC significantly increased follicle vascular development while concurrently increasing the number of large antral follicles produced. In conclusion, we report the production and characterization of a long-acting, bifunctional VEGF-FSH-CTP protein that is superior to combination therapy for enhancing VEGF activity in the ovary and stimulating follicular angiogenesis in rats. PMID:17122074

Trousdale, Rhonda K; Pollak, Susan V; Klein, Jeffrey; Lobel, Leslie; Funahashi, Yasuhiro; Feirt, Nikki; Lustbader, Joyce W

2007-03-01

33

Addition of low dose hCG to rFSh benefits older women during ovarian stimulation for IVF  

PubMed Central

Background To compare the outcome of IVF cycles in women receiving controlled ovarian stimulation with recFSH or recFSH plus low dose hCG. Methods A retrospective case control study, performed at a private practice affiliated with an academic institute. Patients were infertile women who were treated with IVF/ICSI and controlled ovarian stimulation in a long GnRH agonist protocol using either low dose hCG in addition to recFSH [N?=?88] or recFSH alone [N?=?99]. Primary outcomes were mean FSH dose, number of mature eggs, number of fertilized eggs, and serum levels of estradiol. Secondary outcomes were endometrial thickness, cycle cancellations and pregnancy rates. Results A significant increase in number of mature and fertilized eggs was observed in women over 40?years of age using low dose hCG in addition to recFSH. The estradiol level was significantly higher on the day of hCG administration and the serum level of FSH on cycle day 7 and on the day of hCG administration were lower. Conclusion Addition of low dose hCG to recFSH compared with recFSH alone significantly modified cycle characteristics in patients >/= 40?years and could be of potential benefit for IVF cycles in older infertile women. PMID:22866896

2012-01-01

34

FSH in vitro versus LH in vivo: similar genomic effects on the cumulus  

PubMed Central

The use of gonadotropins to trigger oocyte maturation both in vivo and in vitro has provided precious and powerful knowledge that has significantly increased our understanding of the ovarian function. Moreover, the efficacy of most assisted reproductive technologies (ART) used in both humans and livestock species relies on gonadotropin input, mainly FSH and LH. Despite the significant progress achieved and the huge impact of gonadotropins, the exact molecular pathways of the two pituitary hormones, FSH and LH, still remain poorly understood. Moreover, these pathways may not be the same when moving from the in vivo to the in vitro context. This misunderstanding of the intricate synergy between these two hormones leads to a lack of consensus about their use mainly in vitro or in ovulation induction schedules in vivo. In order to optimize their use, additional work is thus required with a special focus on comparing the in vitro versus the in vivo effects. In this context, this overview will briefly summarize the downstream gene expression pathways induced by both FSH in vitro and LH in vivo in the cumulus compartment. Based on recent microarray comparative analysis, we are reporting that in vitro FSH stimulation on cumulus cells appears to achieve at least part of the gene expression activity after in vivo LH stimulation. We are then proposing that the in vitro FSH-response of cumulus cells have similitudes with the in vivo LH-response. PMID:24066945

2013-01-01

35

FSH in vitro versus LH in vivo: similar genomic effects on the cumulus.  

PubMed

The use of gonadotropins to trigger oocyte maturation both in vivo and in vitro has provided precious and powerful knowledge that has significantly increased our understanding of the ovarian function. Moreover, the efficacy of most assisted reproductive technologies (ART) used in both humans and livestock species relies on gonadotropin input, mainly FSH and LH. Despite the significant progress achieved and the huge impact of gonadotropins, the exact molecular pathways of the two pituitary hormones, FSH and LH, still remain poorly understood. Moreover, these pathways may not be the same when moving from the in vivo to the in vitro context. This misunderstanding of the intricate synergy between these two hormones leads to a lack of consensus about their use mainly in vitro or in ovulation induction schedules in vivo. In order to optimize their use, additional work is thus required with a special focus on comparing the in vitro versus the in vivo effects. In this context, this overview will briefly summarize the downstream gene expression pathways induced by both FSH in vitro and LH in vivo in the cumulus compartment. Based on recent microarray comparative analysis, we are reporting that in vitro FSH stimulation on cumulus cells appears to achieve at least part of the gene expression activity after in vivo LH stimulation. We are then proposing that the in vitro FSH-response of cumulus cells have similitudes with the in vivo LH-response. PMID:24066945

Assidi, Mourad; Richard, François J; Sirard, Marc-André

2013-01-01

36

Exogenous administration of recombinant human FSH does not improve germ cell survival in human prepubertal xenografts.  

PubMed

In a previous study, meiotic activity was observed in human intratesticular xenografts from peripubertal patients. However, full spermatogenesis could not be established. The present study aimed to evaluate whether the administration of recombinant human FSH could improve the spermatogonial survival and the establishment of full spermatogenesis in intratesticular human xenografts. Human testicular tissue was obtained from six boys (aged 2.5-12.5years). The testicular biopsy was fragmented and one fragment of 1.5-3.0mm(3) was transplanted to the testis of immunodeficient nude mice. Transplanted mice were assigned to different experimental groups to enable evaluation of the effects of FSH administration and freezing. The structural integrity of the seminiferous tubules, the spermatogonial survival and the presence of differentiated cells were evaluated by histology and immunohistochemistry. Freezing or administration of FSH did not influence tubule integrity and germ cell survival in human xenografts. Meiotic germ cells were observed in the xenografts. More tubules containing only Sertoli cells were observed in frozen-thawed grafts, and more tubules with meiotic cells were present in fresh grafts. There was no clear influence of FSH treatment on meiotic differentiation. Administration of FSH did not improve the establishment of full spermatogenesis after intratesticular tissue grafting. PMID:23352099

Van Saen, Dorien; Goossens, Ellen; Haentjens, Patrick; Baert, Yoni; Tournaye, Herman

2013-03-01

37

Androgen and FSH synergistically stimulate lipoprotein degradation and utilization by ovary granulosa cells  

SciTech Connect

Androgen can directly modulate the induction of steroidogenic enzymes by FSH (follicle stimulating hormone) in ovary granulosa cells. In studies of its mechanism of action, the authors examined the androgen effect on granulosa cell interaction with lipoproteins, the physiologic source of cholesterol. After granulosa cells were cultured for 48 hours with and without androgen and/or FSH, the cells were incubated for 24 hours with /sup 125/I-lipoproteins (human high density lipoprotein (HDL), rat HDL, or human low density lipoprotein (LDL)). The media were then analyzed for lipoprotein protein coat degradation products (mainly /sup 125/I-monoiodotyrosine) and progestin (mainly 20 alpha-dihydroprogesterone (20 alpha-DHP)). In the absence of FSH and androgen, 2 X 10(5) granulosa cells degraded basal levels of all three lipoproteins, but produced no measurable 20 alpha-DHP. The addition of 10(-7) M androstenedione (A), testosterone (T), or 5 alpha-dihydrotestosterone (DHT) had no effect on lipoprotein protein degradation or 20 alpha-DHP production. FSH alone stimulated lipoprotein protein degradation by 50 to 300% while the addition of androgen synergistically augmented the FSH-stimulated 20 alpha-DHP production as well as protein coat degradation of all three lipoproteins. DHT and T were both effective, indicating that androgens themselves, and not estrogen products, were responsible for the effect on lipoprotein protein degradation and 20 alpha-DHP production.

Schreiber, J.R.; Nakamura, K.; Schmit, V.; Weinstein, D.B.

1984-01-01

38

Pubertal Onset in Girls is Strongly Influenced by Genetic Variation Affecting FSH Action  

PubMed Central

Age at pubertal onset varies substantially in healthy girls. Although genetic factors are responsible for more than half of the phenotypic variation, only a small part has been attributed to specific genetic polymorphisms identified so far. Follicle-stimulating hormone (FSH) stimulates ovarian follicle maturation and estradiol synthesis which is responsible for breast development. We assessed the effect of three polymorphisms influencing FSH action on age at breast deveopment in a population-based cohort of 964 healthy girls. Girls homozygous for FSHR -29AA (reduced FSH receptor expression) entered puberty 7.4 (2.5–12.4) months later than carriers of the common variants FSHR -29GG+GA, p = 0.003. To our knowledge, this is the strongest genetic effect on age at pubertal onset in girls published to date. PMID:25231187

Hagen, Casper P.; S?rensen, Kaspar; Aksglaede, Lise; Mouritsen, Annette; Mieritz, Mikkel G.; Tinggaard, Jeanette; Wohlfart-Veje, Christine; Petersen, J?rgen Holm; Main, Katharina M.; Meyts, Ewa Rajpert-De; Almstrup, Kristian; Juul, Anders

2014-01-01

39

Impaired FSH? Expression in the Pituitaries of Foxl2 Mutant Animals  

PubMed Central

Forkhead box L2 (FoxL2) is required for ovarian development and differentiation. FoxL2 is also expressed in the pituitary where it has been implicated in the development and regulation of gonadotropes, which secrete LH and FSH, the endocrine signals that regulate folliculogenesis in the ovary and spermatogenesis in the testis. Here, we show that FoxL2 is not required for the specification of gonadotropes; the pituitaries of Foxl2 mutant mice contain normal numbers of gonadotropes that express glycoprotein ? subunit and LH?. Whereas the specification of gonadotropes and all other hormonal cell types is normal in the pituitaries of Foxl2 mutant animals, FSH? levels are severely impaired in both male and female animals, suggesting that FoxL2 is required for normal Fshb expression. The size of the pituitary is reduced in proportion to the smaller body size of Foxl2 mutants, with a concomitant increase in the pituitary cellular density. In primary pituitary cultures, activin induces FSH secretion and Fshb mRNA expression in cells from wild-type mice. In cells from Foxl2 mutant mice, however, FSH secretion is not detected, and activin is unable to drive Fshb expression, suggesting that the mechanism of activin-dependent activation of Fshb transcription is impaired. However, a small number of gonadotropes in the ventromedial region of the pituitaries from Foxl2 mutant mice maintain FSH? expression, suggesting that a FoxL2- and activin-independent mechanism can drive Fshb transcription. These data indicate that, in addition to its role in the ovary, FoxL2 function in the pituitary is required for normal expression of FSH. PMID:21700720

Justice, Nicholas J.; Blount, Amy L.; Pelosi, Emanuele; Schlessinger, David; Vale, Wylie

2011-01-01

40

Comparison of highly purified urinary versus recombinant FSH: Effect on ART outcomes in polycystic ovary syndrome  

PubMed Central

Background: Polycystic ovary syndrome (PCOS) is a common cause of ovulatory disorders and infertility with high LH to FSH ratio. In order to prevent further increase of LH and follicle atresia, different regimens for ovulation induction have been recommended using FSH alone. Objective: This study was performed in PCOS patients to compare ART outcomes in cycles induced by FSH alone, using either recombinant or urinary products. Materials and Methods: In a randomized trial, from 623 patients who underwent down regulation with GnRH analogue in a long protocol, 160 PCOS patients were randomly divided into two groups of 80. Group A received 150 IU/d recombinant FSH (Gonal-F) and group B 150 IU/d urinary FSH (Fostimon). Results: 33 cases (41.2%) in group A and 36 (45%) in group B achieved clinical pregnancy, which was not significantly different (p=0.67). Total number of oocytes retrieved (13.03±5.56 vs. 14.17±4.89, p=0.17), quality and number of embryos (7.42±3.35 vs. 7.63±3.28, p=0.68) and OHSS rate were similar in group A compared to group B. Endometrial thickness which was 9.66±1.67 mm in group A and 10.36±1.35 mm in group B, showed a significant difference (p=0.004). Conclusion: It seems that in PCOS patients, both pure FSH products used for controlled ovarian hyperstimulation have similar effects on ART outcome and can be used according to availability and patient acceptance without significant difference. PMID:25242998

Sohrabvand, Farnaz; Sheikhhassani, Shahrzad; Bagheri, Maryam; Haghollahi, Fedyeh; Shabihkhani, Maryam; Shariat, Mamak; Nasr Esfahani, Manijeh

2012-01-01

41

Molecular Analysis of a Mutated FSH Receptor Detected in a Patient with Spontaneous Ovarian Hyperstimulation Syndrome  

PubMed Central

Spontaneous ovarian hyperstimulation syndrome (sOHSS) is a rare event that may result from a FSH-producing pituitary adenoma (FSHoma), activating mutations of the FSH receptor (FSHR), and cross-reactivity of the FSHR to elevated hCG and TSH in the setting of pregnancy or hypothyroidism. The objective of this study was to investigate whether an aberrant FSHR was present in a woman with sOHSS and a non-surgically diagnosed FSHoma whose serum FSH levels and FSH bioactivity were nearly normal. Sequencing of the patient’s FSHR gene revealed a heterozygous novel missense mutation c. 1536G>A resulting in an amino acid substitution M512I. We asked whether this mutant FSHR affected FSHR-mediated signaling pathways involving cAMP/protein kinase A (PKA), phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) and v-src sarcoma (Schmidt-Ruppin A-2) viral oncogene homolog kinase (SRC)/ p42/p44 extracellular signal-regulated protein kinases (ERK1/2). Thus, 293T cells expressing wild-type (FSHRwt), the mutant FSHR (FSHRmt), or both (FSHRwt/mt) were treated with FSH and subjected to measurements of intracellular cAMP, cAMP-induced CRE (cAMP response element)-mediated luciferase assays and immunoblot analyses of phosphorylated PI3K and ERK1/2. There were no differences in luciferase activities or phosphorylation levels of ERK1/2 among FSHRwt, FSHRmt cells and FSHwt/mt cells. However, FSHRmt cells showed a significant reduction in both cAMP production and PI3K phosphorylation levels with unchanged phosphorylation of ERK1/2 upon FSH stimulation in comparison to FSHwt cells. Also, FSH treatment did not provoke PI3K phosphorylation in FSHwt/mt cells. These results indicate that the novel missense M512I FSHR mutation identified herein did not participate in hyperactivation of FSHR-mediated signaling pathways but rather in hypoactivation of the FSH-mediated PI3K/AKT pathway. Thus, this study demonstrates a new functional property of this novel mutatnt FSHR, which, however, might not be involved in the pathogenesis of sOHSS in this FSHoma patient. PMID:24058690

Uchida, Sayaka; Uchida, Hiroshi; Maruyama, Tetsuo; Kajitani, Takashi; Oda, Hideyuki; Miyazaki, Kaoru; Kagami, Maki; Yoshimura, Yasunori

2013-01-01

42

FSH and TSH in the Regulation of Bone Mass: The Pituitary/Immune/Bone Axis  

PubMed Central

Recent evidences have highlighted that the pituitary hormones have profound effects on bone, so that the pituitary-bone axis is now becoming an important issue in the skeletal biology. Here, we discuss the topical evidence about the dysfunction of the pituitary-bone axis that leads to osteoporotic bone loss. We will explore the context of FSH and TSH hormones arguing their direct or indirect role in bone loss. In addition, we will focus on the knowledge that both FSH and TSH have influence on proinflammatory and proosteoclastogenic cytokine expression, such as TNF? and IL-1, underlining the correlation of pituitary-bone axis to the immune system. PMID:23818914

Cuscito, Concetta; Colucci, Silvia

2013-01-01

43

Synthetic releasing hormones LH/FSH-RH and LH-RH : effect of intracerebral and intramuscular injections on female carp  

E-print Network

Synthetic releasing hormones LH/FSH-RH and LH-RH : effect of intracerebral and intramuscular extract as well as that of synthetic releasing hormones stimulates the release of gonadotropin from fish in this study as well as intra- muscular injections of synthetic releasing hormones LH/FSH-RH for comparison

Paris-Sud XI, Université de

44

Neonatal androgenization of hypogonadal (hpg) male mice does not abolish estradiol-induced FSH production and spermatogenesis  

Microsoft Academic Search

BACKGROUND: Testicular development is arrested in the hypogonadal (hpg) mouse due to a congenital deficiency in hypothalamic gonadotropin-releasing hormone (GnRH) synthesis. Chronic treatment of male hpg mice with estradiol induces FSH synthesis and secretion, and causes testicular maturation and qualitatively normal spermatogenesis. As estradiol negative feedback normally inhibits FSH production in the male, this study tested whether this paradoxical response

Margaret O Nwagwu; Helen Baines; Jeffrey B Kerr; Francis JP Ebling

2005-01-01

45

Antral follicle count and FSH concentration after clomiphene citrate challenge test in the prediction of ovarian response during IVF treatment  

Microsoft Academic Search

BACKGROUND: We compared: (i) antral follicle count (AFC) in the early follicular phase, after the clomiphene citrate challenge test (CCCT) and before ovarian stimulation following pituitary down-regulation; and (ii) age of women, body mass index, basal and stimulated serum FSH concentrations and AFC in predicting the ovarian response of infertile women aged <40 years with basal FSH < 10 IU\\/l

Ernest Hung; Yu Ng; Carina Chi Wai Chan; Oi Shan Tang; Pak Chung Ho

46

Effects of novel single nucleotide polymorphisms of the FSH beta-subunit gene on semen quality and fertility in bulls  

Microsoft Academic Search

The follicle-stimulating hormone (FSH) acts on the Sertoli cells in the seminiferous tubules of the testis and regulates spermatogenesis up to the secondary spermatocyte stage. This study aimed to investigate molecular genetic characteristics of the bovine FSH ?-subunit gene (FSHB) and elucidate the effects of single nucleotide polymorphisms (SNPs) of FSHB on the quality of fresh and frozen semen and

Lisheng Dai; Zhihui Zhao; Ruifeng Zhao; Shuqi Xiao; Hao Jiang; Xupeng Yue; Xichun Li; Yan Gao; Jifeng Liu; Jiabao Zhang

2009-01-01

47

A comparison of the changes in LH, FSH and testosterone in spring-born ram lambs of two different breeds.  

E-print Network

A comparison of the changes in LH, FSH and testosterone in spring-born ram lambs of two different, Station de Zootechnie, I.N.R.A., 97170 Petit-Bourg, Guadeloupe. Summary. LH, FSH and testosterone and testosterone pulses per hour was higher in Romanov than in Ile-de-France lambs. The mean plasma testosterone

Paris-Sud XI, Université de

48

A FSH-Secreting Pituitary Macroadenoma Causing A Testosterone Deficiency Syndrome  

PubMed Central

FSH-secreting pituitary adenomas can affect sexual and reproductive function. In this article, we have reported the case of a 32-year-old male with secondary infertility. The patient had sexual and reproductive disturbances. The test results of the blood samples indicated obviously decreased testosterone (T) and estradiol (E2) levels. Based on previous hormonal results, the patient received pituitary stimulation and human chorionic gonadotropin (hCG) tests. Both follicle stimulating hormone (FSH) and luteinizing hormone (LH) showed low response during the pituitary stimulation test. The results of the hCG test indicated that T/E2 could recover to a normal level. In addition, this patient was diagnosed with pituitary macroadenoma, which was supported by the pituitary MRI. The man’s sexual and reproductive functions recovered following surgery. The pathological results confirmed that the tumor tissue was an FSH-secreting pituitary adenoma by immunohistochemical staining. The purpose of this report was to review the relative literature and discuss the influence of FSH-secreting pituitary adenomas on hormones through the hypothalamus-pituitary-testis axis. PMID:24696774

Wang, Xiong; Ge, Li; Cui, Yuanqing; Lang, Cuihong; Hao, Cuifang

2014-01-01

49

Inhibitory roles of prohibitin and chemerin in FSH-induced rat granulosa cell steroidogenesis.  

PubMed

Follicular differentiation is a tightly regulated process involving various endocrine, autocrine, and paracrine factors. The biosynthesis of progesterone and estradiol in response to FSH involves the regulation of multiple steroidogenic enzymes, such as p450 cholesterol side-chain cleavage enzyme and aromatase. Here we demonstrated that prohibitin (PHB), a multifunctional protein, inhibits FSH-induced progesterone and estradiol secretion in rat granulosa cells. The mRNA abundances of cyp11a (coding p450 cholesterol side-chain cleavage enzyme) and cyp19 (coding aromatase) were also suppressed by PHB in a time-dependent manner. It is known that a novel adipokine chemerin suppresses FSH-induced steroidogenesis in granulosa cells. Chemerin up-regulates the content of PHB, and PHB knockdown attenuates the suppressive role of chemerin on steroidogenesis. In addition, inhibition of phosphatidylinositol 3-kinase/Akt pathway enhances the suppressive action of PHB, whereas expression of constitutively active Akt attenuates this response. These findings suggest that PHB is a novel negative regulator of FSH-induced steroidogenesis, and its action with chemerin may contribute to the dysregulation of steroidogenesis in the pathogenesis of polycystic ovarian syndrome. PMID:23254195

Wang, Qi; Leader, Arthur; Tsang, Benjamin K

2013-02-01

50

Cloning and sequence analysis of FSH and LH in the giant panda ( Ailuropoda melanoleuca)  

Microsoft Academic Search

The giant panda (Ailuropoda melanoleuca) is an endangered species and indigenous to China. It has been proposed that it has a highly specialized reproductive pattern with low fecundity, but little is known about its basic reproductive biology at the molecular level. In this report the genes encoding gonadotropin subunits ?, follicle-stimulating hormone (FSH) ? and luteinizing hormone (LH) ? of

Ming-Juan Liao; Mu-Yuan Zhu; Zhi-He Zhang; An-Ju Zhang; Guang-Han Li; Fu-Jun Sheng

2003-01-01

51

Effects of fetal bovine serum, FSH and 17?-estradiol on the culture of bovine preantral follicles  

Microsoft Academic Search

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH and 17?-estradiol on the morphology and growth of the preantral follicles was investigated in medium without FBS. After culture in medium with 10% FBS, the increase

S. C. J. Hulshof; J. R. Figueiredo; J. F. Beckers; M. M. Bevers; J. A. van der Donk; R. van den Hurk

1995-01-01

52

FSH withdrawal improves developmental competence of oocytes in the bovine model.  

PubMed

Combinations of genetic, environmental, and management factors are suspected to explain the loss in fertility observed for over 20 years in dairy cows. In some cases, IVF is used. When compared with in vivo embryo production, IVF resulted in low success rates until the FSH coasting process (FSH starvation after superstimulation) was introduced in 2002. Increased competence associated with FSH withdrawal of aspirated oocyte for in vitro maturation and IVF has not been optimized nor explained yet. The goal here was to determine and characterize the optimal oocyte competence acquisition window during the coasting period by determining blastocyst rates and follicular cohort development. Commercial milking cycling cows (n=6) were stimulated with 3 days of FSH (6×40?mg NIH Folltropin-V given at 12?h intervals) followed by a coasting period of 20, 44, 68, or 92?h. Each animal was exposed to the four conditions and served as its own control. At the scheduled time, transvaginal aspirations of immature oocytes were performed followed by IVF of half the oocytes. The outcomes were as follows: i) FSH coasting was optimal at a defined period: between 44 and 68?h of coasting; ii) The best estimated coasting duration was ?54±7?h; iii) Under these conditions, the best statistical blastocyst rate estimation was ?70%; iv) Between 44 and 68?h of coasting, follicle size group proportions were similar; v) Follicle diameter was not linearly associated with competence. In conclusion, coasting duration is critical to harvest the oocytes at the right moment of follicular differentiation. PMID:22080141

Nivet, Anne-Laure; Bunel, Audrey; Labrecque, Rémi; Belanger, Josée; Vigneault, Christian; Blondin, Patrick; Sirard, Marc-André

2012-02-01

53

Polymorphism of follicle stimulating hormone beta (FSH?) subunit gene and its association with litter traits in giant panda.  

PubMed

The different SSCP patterns of the follicle stimulating hormone beta (FSH?) gene amplified by three pairs of primers were sequenced. Comparisons among the three nucleotide sequences of three genotypes indicated that three base substitutions (A213T, A91G, and A89C) were detected in FSH? gene, which A213T substitution led to one amino acids mutation (Lys > Met), and the other two substitutions were synonymous mutations. The AA, AB and BB genotypes patterns obtained by FSH? primer1 had evident relation with the litter traits, but the SSCP genotypes patterns obtained by FSH? primer2 and primer3 had no evident relation with the litter traits in giant panda. The giant panda with AA and AB genotype had the largest litter size and multiparity rate compared with the BB genotypes (P < 0.05). We speculated that the giant pandas with the A allele have better litter traits than those with the B allele. PMID:24057246

Huang, Xiaoyu; Li, Desheng; Wang, Jiwen; Huang, Yan; Han, Chunchun; Zhang, Guiquan; Huang, Zhi; Wu, Honglin; Wei, Ming; Wang, Guosong; Hu, Haiping; Deng, Tao; He, Tao; Zhou, Yingming; Song, Shixian; Luo, Bo; Zhang, Heming

2013-11-01

54

Serum LH and FSH Responses to Synthetic LH-RH in Normal Infants, Children and Patients With Turner's Syndrome  

ERIC Educational Resources Information Center

Effects of luteinizing hormone-releasing hormone (LH-RH) on LH and follicle-stimulating hormone (FSH) release were studied in 26 normal children and six patients (from 1-to 14-years-old) with Turner's syndrome. (Author)

Suwa, Seizo; And Others

1974-01-01

55

Regulation of Sertoli-Germ Cell Adhesion and Sperm Release by FSH and Nonclassical Testosterone Signaling  

PubMed Central

Testosterone and FSH act in synergy to produce the factors required to maximize the production of spermatozoa and male fertility. However, the molecular mechanisms by which these hormones support spermatogenesis are not well established. Recently, we identified a nonclassical mechanism of testosterone signaling in cultured rat Sertoli cells. We found that testosterone binding to the androgen receptor recruits and activates Src tyrosine kinase. Src then causes the activation of the epidermal growth factor receptor, which results in the phosphorylation and activation of the ERK MAPK and the cAMP response element-binding protein transcription factor. In this report, we find that FSH inhibits testosterone-mediated activation of ERK and the MAPK pathway in Sertoli cells via the protein kinase A-mediated inhibition of Raf kinase. In addition, FSH, as well as inhibitors of Src and ERK kinase activity, reduced germ cell attachment to Sertoli cells in culture. Using pathway-specific androgen receptor mutants we found that the nonclassical pathway is required for testosterone-mediated increases in germ cell attachment to Sertoli cells. Studies of seminiferous tubule explants determined that Src kinase, but not ERK kinase, activity is required for the release of sperm from seminiferous tubule explants. These findings suggest the nonclassical testosterone-signaling pathway acts via Src and ERK kinases to facilitate the adhesion of immature germ cells to Sertoli cells and through Src to permit the release of mature spermatozoa. In contrast, FSH acts to limit testosterone-mediated ERK kinase activity and germ cell attachment. PMID:21177760

Shupe, John; Cheng, Jing; Puri, Pawan; Kostereva, Nataliya

2011-01-01

56

Importance of Inhibin B in the Regulation of FSH Secretion in the Human Male  

Microsoft Academic Search

Regulation of FSH secretion in the male involves a complex balance between stimulation by GnRH from the hypothala- mus, inhibitory feedback by sex steroids (T and E2) and in- hibin B (Inh B) from the gonads, and autocrine\\/paracrine mod- ulation by activin and follistatin within the pituitary. The aim of the present study was to delineate the feedback control of

FRANCES J. HAYES; NELLY PITTELOUD; PAUL A. BOEPPLE

57

Purification and characterization of an FSH releasing protein from porcine ovarian follicular fluid  

Microsoft Academic Search

A variety of hypophysiotropic peptides or proteins have been reported to be present in mammalian gonads. Inhibin, a hormone that under most circumstances selectively suppresses the secretion of follicle-stimulating hormone (FSH) but not luteinizing hormone (LH), has been isolated from the gonadal fluids of several species1-5 and characterized as a heterodimeric protein consisting of alpha- and beta-polypeptides associated by disulphide

Wylie Vale; Jean Rivier; Joan Vaughan; Richard McClintock; Anne Corrigan; Wilson Woo; David Karr; Joachim Spiess

1986-01-01

58

Prenatal testosterone excess alters Sertoli and germ cell number and testicular FSH receptor expression in rams.  

PubMed

Exposure to excess testosterone (T) during fetal life has a profound impact on the metabolic and reproductive functions in the female's postnatal life. However, less is known about the effects of excess testosterone in males. The aim of the present study was to evaluate the impact (consequences) of an excess of T during fetal development on mature male testis. The testicular evaluation was by histological analysis and by determination of mRNA expression of the FSH receptor (FSH-R), transforming growth factor-? type I receptor (T?R-I), and two members of the TGF-? superfamily, transforming growth factor-?3 (TGF?3) and anti-Müllerian hormone (AMH) in males born to mothers receiving an excess of T during pregnancy. At 42 wk of age, postpubertal males born to mothers treated with 30 mg of T propionate twice weekly from day 30 to 90, followed by 40 mg of T propionate from day 90 to 120 of pregnancy (T males), showed higher concentrations of FSH in response to a GnRH analog, a higher number of Sertoli cells/seminiferous tubule cross-section, and a lower number of germ cells/tubules (P < 0.05) than control males (C males) born to mothers treated with the vehicle. The mRNA expression of FSH-R and of T?R-I was higher in T males compared with C males (P < 0.05). Moreover, in T males, AMH expression level correlated negatively with the expression level of TGF?3. In C males, this latter correlation was not observed. These results suggest that prenatal exposure to an excess of T can negatively modify some histological and molecular characteristics of the mature testis. PMID:20858754

Rojas-García, Pedro P; Recabarren, Mónica P; Sarabia, Luis; Schön, Jennifer; Gabler, Christoph; Einspanier, Ralf; Maliqueo, Manuel; Sir-Petermann, Teresa; Rey, Rodolfo; Recabarren, Sergio E

2010-12-01

59

Serum levels of LH, FSH, estradiol and progesterone in female rats experimentally infected by Trypanosoma evansi.  

PubMed

The goal of this study was to evaluate reproductive hormones in sera samples of female rats experimentally infected by Trypanosoma evansi during different phases of the estrous cycle. For that, 64 animals were divided into two groups: 24 rats for the control group (uninfected), and 40 animals were infected by T. evansi. These groups were divided into subgroups according to the time of infection (days 5 and 15 post-infection; PI) and the phase of the estrous cycle (proestrus, estrus, metestrus and diestrus). Serum was collected at days 5 and 15 PI and the levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone and estradiol were assessed by enzyme immunoassay technique. The concentration of nitrite/nitrate (NOx), advanced oxidation protein products (AOPP), and thiobarbituric acid reactive substances (TBARS) were measured in ovaries and uteruses in these same periods. Infected females showed significant decrease (P<0.05) of LH, FSH, estradiol and progesterone in different periods and phases of the estrous cycle when compared to uninfected rats. In addition, it was observed an increase in the concentration of NOx, AOPP, and TBARS in the ovaries, which is indicative of cell damage. Therefore, our experimental study showed that T. evansi infection in female rats may cause changes in LH, FSH, estradiol, and progesterone levels regardless of the time of infection or phase of the estrous cycle. PMID:23816642

Faccio, Luciana; Da Silva, Aleksandro S; Tonin, Alexandre A; França, Raqueli T; Gressler, Lucas T; Copetti, Maíra M; Oliveira, Camila B; Sangoi, Manuela B; Moresco, Rafael N; Bottari, Nathieli B; Duarte, Marta M M F; Monteiro, Silvia G

2013-09-01

60

FSHR polymorphism p.N680S mediates different responses to FSH in vitro.  

PubMed

The single nucleotide polymorphism p.N680S of the follicle-stimulating hormone (FSH) receptor (FSHR) is a discrete marker of ovarian response but previous in vitro studies failed to demonstrate differences in the response to FSH between N and S carrier cells. Here we demonstrate that p.N680S mediates different kinetics of the response to FSH in vitro. Intracellular cAMP production is faster in p.N680S N than in S homozygous human granulosa cells (45 versus 90 min to achieve the plateau, respectively; Mann-Whitney's U-test; p < 0.005; n = 4). Reflecting the cAMP kinetics, phospho-ERK1/2 and -CREB activation, AREG and STARD1 gene expressions and progesterone production were qualitatively and quantitatively different in N versus S homozygous cells. Finally, the blockade of ERK pathway by U0126 abolishes the genotype-mediated different effects on gene expression and progesterone production (Mann-Whitney's U-test; p ? 0.005; n = 3). PMID:24970684

Casarini, Livio; Moriondo, Valeria; Marino, Marco; Adversi, Francesca; Capodanno, Francesco; Grisolia, Chiarina; La Marca, Antonio; La Sala, Giovanni Battista; Simoni, Manuela

2014-08-01

61

Identification and expression analyses of BAMBI mediated by FSH in swine luteinizing granulosa cells.  

PubMed

Transforming growth factor-? and related growth factors are essential regulators for the development of follicles. Bone morphogenic protein (BMP) and activin membrane-bound inhibitor (BAMBI) was reported as a key factor participating in the transforming growth factor-? signal pathway. To investigate the role of BAMBI in porcine granulosa cells, the full length of the BAMBI was cloned from porcine ovarian cDNA. The results of bioinformatics analyses showed that the signaling peptide was located in between positions 20 and 21. The results of online prediction on phosphorylation sites indicate that the sites of Ser, Thr, and Tyr are 9, 1, and 1, respectively. In addition, BAMBI was highly homologous in rodent and livestock. Real-time quantitative polymerase chain reaction (qPCR) indicated that BAMBI was widely expressed in porcine tissues. Immunofluorescence showed that BAMBI was located in both nucleus and cytoplasm. Stimulating the granulosa cells with FSH in vitro could alter BAMBI expression level in a time-dependent manner. Moreover, the expression level declined after treatment with FSH. These results indicated that BAMBI is an FSH-repressed gene in porcine luteinizing granulosa cells and it may be involved in the regulation of ovarian follicle development and oocyte maturation. PMID:25168722

Bai, Long; Chu, Guiyan; Mai, Yin; Zheng, Jiameng; Wang, Wusu; Zhang, Qiangling; Yang, Gongshe

2014-11-01

62

The effect of Ramadan fasting on LH, FSH, oestrogen, progesterone and leptin in pregnant women.  

PubMed

Many pregnant Muslim women fast during Ramadan. Leptin has an important role in the reproductive system and hormones. In this study, FSH, LH, oestrogen, progesterone and leptin were measured in the first, second and fourth week of Ramadan and the second week post-Ramadan, in 30 fasting pregnant women. Data were analysed using repeated measures ANOVA by SPSS. The weight and BMI did not change during the study. A significant change in FSH, oestrogen, progesterone and leptin was observed (p < 0.05). The lowest value of FSH was in the second week of Ramadan. Progesterone increased at the end of Ramadan and the second week after. Oestrogen increased significantly during Ramadan and decreased after Ramadan. A decreasing trend was seen in LH during the Ramadan and 2 weeks after (p < 0.1). Leptin decreased significantly 2 weeks after Ramadan. We found poor weight gain and hypoleptinaemia in pregnant fasted women during the study. Food restriction in pregnant fasted women during Ramadan may induce poor weight gain during pregnancy. These data confirm that Ramadan fasting by pregnant women may have potential risks during pregnancy. We recommend further study to evaluate long-term effects of Ramadan fasting during pregnancy in different countries with different food habits and traditions, to obtain reliable and documented data. PMID:24914688

Khoshdel, A; Kheiri, S; Hashemi-Dehkordi, E; Nasiri, J; Shabanian-Borujeni, S; Saedi, E

2014-10-01

63

Identification of immunoreactive FSH and LH cells in the cichlid fish Cichlasoma dimerus during the ontogeny and sexual differentiation  

Microsoft Academic Search

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) expressing cells were detected in pituitary, brain and ovary\\u000a of the Perciform cichlid fish Cichlasoma dimerus. This detection was carried out by immunohistochemistry (IHC) and Western blot techniques using antisera of the Cyprinodontiform\\u000a Fundulus heteroclitus raised against the conservative region of the teleost ?FSH and the ?LH subunits. The estimated molecular weights were

Matías Pandolfi; Fabiana L. Lo Nostro; Akio Shimizu; Andrea G. Pozzi; Fernando J. Meijide; Graciela Rey Vazquez; M. Cristina Maggese

2006-01-01

64

Activation of the PI3K/AKT pathway mediates FSH-stimulated VEGF expression in ovarian serous cystadenocarcinoma.  

PubMed

There is evidence to suggest that follicle-stimulating hormone (FSH) can facilitate the neovascularization of ovarian cancers by increasing vascular endothelial growth factor (VEGF) expression in cancer cells, although the underlying molecular mechanism of this process is not well known. Therefore, we investigated the effect of FSH on VEGF expression in the ovarian cancer cell lines SKOV-3 and ES-2. Treatment with FSH significantly increased VEGF expression in a dose- and time-dependent manner. In addition, FSH treatment enhanced the expression of survivin and hypoxia-inducible factor-1 (HIF-1alpha). Knockdown of survivin or HIF-1alpha suppressed VEGF expression, but only knockdown of survivin inhibited FSH-stimulated VEGF expression. Pretreatment with LY294002, a phosphoinositide 3-kinase (PI3K)/AKT inhibitor, neutralized the enhanced expression of survivin induced by FSH, but treatment with U0126, a mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor, had no such effect. We further showed that ovarian serous cystadenocarcinoma samples had much higher incidence of positive AKT and phosphorylated AKT (pAKT) protein staining than did benign ovarian cystadenoma samples (p < 0.01). The 5-year survival rate was only about 15% in patients with ovarian serous cystadenocarcinoma who had AKT and pAKT expression, whereas it was about 80% in those who did not have AKT or pAKT expression. Taken together, these results indicate that FSH increases the expression of VEGF by upregulating the expression of survivin, which is activated by the PI3K/AKT signaling pathway. Understanding the role of the PI3K/AKT pathway in FSH-stimulated expression of survivin and VEGF will be beneficial for evaluating the prognosis for patients with ovarian serous cystadenocarcinoma and for pursuing effective treatment against this disease. PMID:18574502

Huang, Yan; Hua, Keqin; Zhou, Xianrong; Jin, Hongyan; Chen, Xiaojun; Lu, Xin; Yu, Yinhua; Zha, Xiliang; Feng, Youji

2008-07-01

65

Brulures par Diluant  

PubMed Central

Summary La flamme de diluant est une cause non rare de brûlure dans le contexte marocain. Nous avons jugé intéressant de faire une étude épidémiologique sur la brûlure par flamme de diluant (BFD) au centre national des brûlés (CNB) du CHU Ibn-Rochd de Casablanca. Ce travail a été réalisé sur une période de 10 mois (septembre 2007/juin 2008). Le but du travail est de montrer les caractéristiques de ce type de brûlures pour les prévenir et ce par l'information sur le diluant, produit causant ces brûlures, et ses différents dangers, la brûlure notamment. Durant cette période, nous avons colligé 17 cas de BFD sur un total de 356 patients admis au CNB pour brûlures aiguës toute étiologie confondue. La moyenne d'age des patients concernés est de 32 ans. Ils sont presque tous de sexe masculin (16 hommes/1 femme) et ont des antécédents de toxicomanie et/ou de délinquance. Tous nos patients sont de bas niveau socio-économique et habitent dans des bidonvilles pour la plupart. La brûlure est souvent secondaire à une agression dans la rue (92% des cas). Concernant les caractéristiques de la brûlure, la surface cutanée brûlée moyenne est de 23%; elle est souvent profonde et siège surtout au niveau des membres supérieurs et du tronc. PMID:21991179

Benbrahim, A.; Jerrah, H.; Diouri, M.; Bahechar, N.; Boukind, E.H.

2009-01-01

66

PKC? and ? Possibly Mediate FSH-Induced Mouse Oocyte Maturation via NOX-ROS-TACE Cascade Signaling Pathway  

PubMed Central

In mammals, gonadotropins stimulate oocyte maturation via the epidermal growth factor (EGF) network, and the protein kinase C (PKC) signaling pathway mediates this process. Tumor necrosis factor-? converting enzyme (TACE) is an important protein responding to PKC activation. However, the detailed signaling cascade between PKC and TACE in follicle-stimulating hormone (FSH)-induced oocyte maturation in vitro remains unclear. In this study, we found that rottlerin (mallotoxin, MTX), the inhibitor of PKC ? and ?, blocked FSH-induced maturation of mouse cumulus-oocyte complexes (COCs) in vitro. We further clarified the relationship between two molecules downstream of PKC ? and ? and TACE in COCs: nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) and its products, reactive oxygen species (ROS). We proved that the respective inhibitors of NOX, ROS and TACE could block FSH-stimulated oocyte maturation dose-dependently, but these inhibitory effects could be reversed partially by amphiregulin (Areg), an EGF family member. Notably, inhibition of PKC ? and ? prevented FSH-induced translocation of two cytosolic components of NOX, p47phox and p67phox, to the plasma membrane in cumulus cells. Moreover, FSH-induced TACE activity in cumulus cells was decreased markedly by inhibition of NOX and ROS. In conclusion, PKC ? and ? possibly mediate FSH-induced meiotic resumption in mouse COCs via NOX-ROS-TACE signaling pathway. PMID:25350560

Ran, Hao; Feng, Lizhao; Yan, Hao; Mu, Xinyi; Han, Yingying; Liu, Wei; Xia, Guoliang; Wang, Chao

2014-01-01

67

Molecular cloning of follicle-stimulating hormone (FSH)-beta subunit cDNA from duck pituitary.  

PubMed

We have cloned FSH-beta cDNA from duck pituitary gland by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE) methods. The cloned duck FSH-beta cDNA contains 1909-bp nucleotides including 396-bp of open-reading frame and 1491-bp of 3'-untranslational region. The open-reading frame encodes a 131-amino acid protein with a putative 20-amino acid signal peptide and a putative 111-amino acid mature protein. The deduced amino acid sequence shows a remarkable similarity (94-98%) to those of other avian FSH-beta subunits; while it exhibits lower similarities with those of turtles (82-84%), mammals (63-71%), and amphibians (53-57%). The structural model analysis of duck FSH suggests that the cysteine-knot and beta-strands for maintaining the specific structural frame, and the "seat-belt" loop for specific binding to FSH receptor have been conserved in tetrapodian FSH-betas. PMID:16674957

Shen, San-Tai; Cheng, Yi-Sheng; Shen, Tzu-Yun; Yu, John Yuh-Lin

2006-09-15

68

Growth differentiation factor 9 (GDF9) forms an incoherent feed-forward loop modulating follicle-stimulating hormone ?-subunit (FSH?) gene expression.  

PubMed

Gonadotropin-releasing hormone (GnRH) is secreted in brief pulses from the hypothalamus and regulates follicle-stimulating hormone ?-subunit (FSH?) gene expression in pituitary gonadotropes in a frequency-sensitive manner. The mechanisms underlying its preferential and paradoxical induction of FSH? by low frequency GnRH pulses are incompletely understood. Here, we identify growth differentiation factor 9 (GDF9) as a GnRH-suppressed autocrine inducer of FSH? gene expression. GDF9 gene transcription and expression were preferentially decreased by high frequency GnRH pulses. GnRH regulation of GDF9 was concentration-dependent and involved ERK and PKA. GDF9 knockdown or immunoneutralization reduced FSH? mRNA expression. Conversely, exogenous GDF9 induced FSH? expression in immortalized gonadotropes and in mouse primary pituitary cells. GDF9 exposure increased FSH secretion in rat primary pituitary cells. GDF9 induced Smad2/3 phosphorylation, which was impeded by ALK5 knockdown and by activin receptor-like kinase (ALK) receptor inhibitor SB-505124, which also suppressed FSH? expression. Smad2/3 knockdown indicated that FSH? induction by GDF9 involved Smad2 and Smad3. FSH? mRNA induction by GDF9 and GnRH was synergistic. We hypothesized that GDF9 contributes to a regulatory loop that tunes the GnRH frequency-response characteristics of the FSH? gene. To test this, we determined the effects of GDF9 knockdown on FSH? induction at different GnRH pulse frequencies using a parallel perifusion system. Reduction of GDF9 shifted the characteristic pattern of GnRH pulse frequency sensitivity. These results identify GDF9 as contributing to an incoherent feed-forward loop, comprising both intracellular and secreted components, that regulates FSH? expression in response to activation of cell surface GnRH receptors. PMID:24778184

Choi, Soon Gang; Wang, Qian; Jia, Jingjing; Pincas, Hanna; Turgeon, Judith L; Sealfon, Stuart C

2014-06-01

69

Independent Activities of FSH and LH Structurally Confined in a Single Polypeptide: Selective Modification of the Relative Potencies of the Hormones  

Microsoft Academic Search

The human glycoprotein hormones CG, LH, FSH, and TSH are heterodimers composed of a common subunit noncovalently associated with a hormone-specific subunit. Recently, it was reported that a covalently fused triple-domain gonadotropin analog containing FSH ,C G, and subunits was dually ac- tive because it bound to both FSH and human CG (hCG)\\/LH receptors. However, it is not known whether

VICENTA GARCIA-CAMPAYO; IRVING BOIME

2001-01-01

70

Gene expression analysis of bovine oocytes with high developmental competence obtained from FSH-stimulated animals.  

PubMed

Recent progress in the ovarian stimulation protocol used for bovine in vitro maturation and fertilization, especially through optimization of the follicle-stimulating hormone (FSH) withdrawal period ("coasting") after ovarian pre-treatment with FSH, has significantly improved blastocyst outcome. Despite this important success, the underlying factors leading to improved oocyte quality have not yet been identified. The aim of this project was to compare the transcriptome of germinal vesicle-stage oocytes collected from FSH-stimulated cows after various coasting periods (20, 44, 68, and 92 hr) to determine which transcripts were accumulated or depleted during the rise and fall of competence. Oocytes from each coasting period were compared to the three other times (optimal conditions, 44 and 68 hr; under-matured, 20 hr; and over-matured, 92 hr) per animal, allowing each cow to be its own control (24 collections). Microarray analysis revealed that between 5 and 338 transcripts were significantly different across the six comparisons, with an important longitudinal modulation in terms of gene expression profile. Not surprisingly, as the transcriptional activity decreased in these oocytes, several transcripts that are significantly modulated during coasting are related to RNA processing functions, as shown by functional analysis. Ingenuity Pathway Analysis also highlighted another important function: the control of chromosome segregation. The results presented here indicate that the quality gained with the optimal coasting time does not last, and also suggests a possible mechanism of control by transcript degradation that could be implicated if the oocyte is not ovulated at the right time. PMID:23559376

Labrecque, Rémi; Vigneault, Christian; Blondin, Patrick; Sirard, Marc-André

2013-06-01

71

Meiosis activating sterol (MAS) regulate FSH-induced meiotic resumption of cumulus cell-enclosed porcine oocytes via PKC pathway.  

PubMed

Meiosis activating sterol (MAS) have been found to be able to promote oocytes meiotic maturation of small animals in vitro, such as mouse, rat and rabbit. But in large animals, whether MAS play the same function, especially the physiological mechanisms of MAS on oocytes maturation are not clear. To our knowledge, this is the first time to investigate the role and signal pathway of MAS on FSH-induced porcine oocytes meiotic resumption. Porcine cumulus-enclosed oocytes (CEOs) isolated from 3 to 5mm follicles were cultured in the FSH-medium for 24h supplemented with 0-50 microM RS21745 or 0-100 microM RS21607 (two specific inhibitors of lanosterol 14alpha-demethylase that converts lanosterol to FF-MAS), or cultured in FSH-medium with 25 microM RS21745 for 0-24h firstly, then transferred into a new FSH-medium (the total culture time is 24h). The results revealed that RS21745 or RS21607 could inhibit FSH-induced porcine CEOs meiotic resumption in a dose and time-dependent manner. Meanwhile, FSH-induced cumulus expansion could also be inhibited dose-dependently by RS21745 or RS21607. Otherwise, AY9944-A-7, an inhibitor of Delta14-reductase which promotes cholesterol accumulation from FF-MAS, had no effect on both denuded oocytes (DOs) cultured for 24 or 44 h and CEOs cultured for 24h meiotic resumption, but it could promote CEOs meiotic resumption after 44 h culture. In addition, we got that 10(-8) to 10(-6)M PMA, an activator of PKC pathway, could reverse the inhibiting effect of RS21745 on FSH-induced CEOs meiotic resumption and enhance the rate of germinal vesicle breakdown (GVBD) of CEOs cultured in medium with hypoxanthine (HX). Moreover, 5-10 microM chelerythrine chloride, an inhibitor of PKC, could enhance the inhibitory effect of RS21745 on FSH-induced porcine oocytes resumption of meiosis. All the data of this study support that endogenous FF-MAS takes part in the FSH-induced porcine oocytes meiotic resumption and might play an active role via PKC signal pathway. PMID:16500744

Jin, Shiying; Zhang, Meijia; Lei, Lei; Wang, Chao; Fu, Maoyong; Ning, Gang; Xia, Guoliang

2006-04-25

72

Par Pond vegetation status 1996  

SciTech Connect

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned.

Mackey, H.E. Jr.; Riley, R.S.

1996-12-01

73

Evidence for FSH-dependent upregulation of SPATA2 (spermatogenesis-associated protein 2).  

PubMed

Here we report the cloning and characterization of a novel cDNA named spata 2. SPATA2 is the ortholog of PD1, a human testicular protein which has been suggested to play a role in spermatogenesis. The spata 2 sequence reveals an open reading frame encoding a protein of 511 amino acids. Northern blot analysis with rat mRNA demonstrated two distinct transcripts of 2.2 and 4.0 kb. Tagging recombinant SPATA2 with the green fluorescent protein (GFP) and expressing the chimeric polypeptide in HLtat transfected cells indicated that SPATA2 is located in the nucleus. RT-PCR analysis revealed that spata 2 mRNA is expressed in the testis and to a lesser extent in the brain while skeletal muscle and kidney showed a barely visible signal. The same analysis demonstrated that isolated Sertoli cells express spata 2 mRNA. Treating Sertoli cells with FSH in vitro induced remarkable changes in the steady-state level of spata 2 mRNA in a time-dependent manner. In developing testis spata 2 transcripts were first detected 10 days post partum and expression levels increased steadily with age. The ability of FSH to stimulate spata 2 mRNA expression as well as its developmental expression suggests that this protein might play a role in regulating spermatogenesis and thus, according to the Gene Nomenclature Committee, we propose the name SPATA2 (Spermatogenesis associated protein 2) for this protein (or gene). PMID:11322771

Onisto, M; Slongo, L M; Graziotto, R; Zotti, L; Negro, A; Merico, M; Moro, E; Foresta, C; Maurizio, O; Liliana, S M; Romina, G; Lorenza, Z; Alessandro, N; Maurizio, M; Enrico, M; Carlo, F

2001-04-27

74

'Value of FSH and inhibin-B measurements in the diagnosis of azoospermia'--a clinician's overview.  

PubMed

Azoospermia can be either of obstructive ctiology or due to the testis' failure to initiate or maintain spermatogenesis. FSH acts through its receptor at Sertoli cell level and modulates spermatogenesis initiation and maintenance. Inhibin B is a Sertoli cell product expressing the functional capacity of the cell and in an indirect way the state of seminiferous tubule activity. Both FSH and inhibin B differentiate clearly testicular from extra-testicular pathology of azoospermia while, none of these hormones has been convincingly established as predictory index for the finding of spermatozoa in TESE. PMID:19703093

Adamopoulos, D A; Koukkou, E G

2010-02-01

75

Pretreatment with recombinant bovine somatotropin enhances the superovulatory response to FSH in heifers.  

PubMed

One of the primary limiting factors to superovulation and embryo transfer in cattle has been the large variability in response, both between and within animals. It appears that the primary source of this problem is the variability in the population of gonadotropin-responsive follicles present in ovaries at the time of stimulation. We have shown that treatment of heifers with recombinant bovine somatotropin (rbGH) increases the number of small antral follicles (2 to 5 mm) and, therefore, enhances the subsequent superovulatory response to eCG. To investigate further the potential of using this approach to improve superovulatory regimens in cattle, the effect of rbGH pretreatment on the response to pituitary FSH was studied. The estrous cycles of 16 heifers were synchronized using PGF2alpha. On Day 7 of the synchronized cycle, half of the animals were injected with 320 mg sustained-release formulated rbGH, while the other half received 10 ml saline. Five days later, all heifers were given a decreasing-dose regimen of twice daily injections of oFSH for 4 d, incorporating an injection of PGF2alpha with the fifth FSH treatment, to induce superovulation. All animals were artificially inseminated twice with semen from the same bull during estrus. Ova/embryos were recovered nonsurgically on Days 6 to 8 of the following estrous cycle, and the ovulation rate assessed on Day 9 by laparoscopy. Using the same animals as described above, the experiment was repeated twice, 3 and 6 mo later, with no laparoscopy in the third experiment. The animals were randomized both between experiments and for the day of ova/embryo collection. Pretreatment of heifers with rbGH significantly (P < 0.01) increased the number of ovulations, total number of ova/embryos recovered and the number of transferable embryos. The percentage of transferable embryos was significantly (P < 0.05) increased by rbGH pretreatment. In addition, the incidence (2/16) of follicular cysts with a poor ovulatory response (< 6 ovulations) for the rbGH-pretreated heifers was significantly lower (P < 0.05) when compared with the incidence (7/16) in the control animals. It is concluded that pretreatment with rbGH may provide a useful approach for improving superovulatory response in cattle. PMID:16727823

Gong, J G; Wilmut, I; Bramley, T A; Webb, R

1996-02-01

76

Shortened estrous cycle length, increased FSH levels, FSH variance, oocyte spindle aberrations, and early declining fertility in aging senescence-accelerated mouse prone-8 (SAMP8) mice: concomitant characteristics of human midlife female reproductive aging.  

PubMed

Women experience a series of specific transitions in their reproductive function with age. Shortening of the menstrual cycle begins in the mid to late 30s and is regarded as the first sign of reproductive aging. Other early changes include elevation and increased variance of serum FSH levels, increased incidences of oocyte spindle aberrations and aneuploidy, and declining fertility. The goal of this study was to investigate whether the mouse strain senescence-accelerated mouse-prone-8 (SAMP8) is a suitable model for the study of these midlife reproductive aging characteristics. Midlife SAMP8 mice aged 6.5-7.85 months (midlife SAMP8) exhibited shortened estrous cycles compared with SAMP8 mice aged 2-3 months (young SAMP8, P = .0040). Midlife SAMP8 mice had high FSH levels compared with young SAMP8 mice, and mice with a single day of high FSH exhibited statistically elevated FSH throughout the cycle, ranging from 1.8- to 3.6-fold elevation on the days of proestrus, estrus, metestrus, and diestrus (P < .05). Midlife SAMP8 mice displayed more variance in FSH than young SAMP8 mice (P = .01). Midlife SAMP8 ovulated fewer oocytes (P = .0155). SAMP8 oocytes stained with fluorescently labeled antitubulin antibodies and scored in fluorescence microscopy exhibited increased incidence of meiotic spindle aberrations with age, from 2/126 (1.59%) in young SAMP8 to 38/139 (27.3%) in midlife SAMP8 (17.2-fold increase, P < .0001). Finally, SAMP8 exhibited declining fertility from 8.9 pups/litter in young SAMP8 to 3.5 pups/litter in midlife SAMP8 mice (P < .0001). The age at which these changes occur is younger than for most mouse strains, and their simultaneous occurrence within a single strain has not been described previously. We propose that SAMP8 mice are a model of midlife human female reproductive aging. PMID:24654787

Bernstein, Lori R; Mackenzie, Amelia C L; Kraemer, Duane C; Morley, John E; Farr, Susan; Chaffin, Charles L; Merchenthaler, István

2014-06-01

77

Concanavalin-A induces granulosa cell death and inhibits FSH-mediated follicular growth and ovarian maturation in female rats.  

PubMed

Reproductive success stems from a finely regulated balance between follicular maturation and atresia, in which the role of carbohydrate structure is poorly understood. Here, we describe for the first time a fraction of purified recombinant human FSH that is capable of bringing about the cell death of granulosa cells and preventing follicular maturation in a rat model. Further analysis by mass spectrometry revealed the presence of the lectin Concanavalin-A (Con-A) within this fraction of recombinant FSH. Using both the fractionated FSH and Con-A, the observed cell death was predominantly located to the granulosa cells. Ex vivo culture of rat follicles demonstrated that follicle degeneration occurred and resulted in the release of a denuded and deteriorated oocyte. Moreover, in vivo experiments confirmed an increase in atresia and a corresponding reduction confined to follicle in early antral stage. As a mechanism of action, Con-A reduces ovarian proliferation, Von Willebrand staining, and angiogenesis. Based on the observation that Con-A may induce granulosa cell death followed by follicle death, our results further demonstrate that follicular carbohydrate moiety is changing under the influence of FSH, which may allow a carbohydrate-binding lectin to increase granulosa cell death. The physiological consequences of circulating lectin-like molecules remain to be determined. However, our results suggest a potential exploitation of carbohydrate binding in fertility and ovarian cancer treatment. This work may shed light on a key role of carbohydrates in the still obscure physiological process of follicular selection and atresia. PMID:23515285

Velasquez, Ethel V; Ríos, Mariana; Ortiz, María Elena; Lizama, Carlos; Nuñez, Elizabeth; Abramovich, Dalhia; Orge, Felipe; Oliva, Barbara; Orellana, Renán; Villalon, Manuel; Moreno, Ricardo D; Tesone, Marta; Rokka, Anne; Corthals, Garry; Croxatto, Horacio B; Parborell, Fernanda; Owen, Gareth I

2013-05-01

78

Characterization of human FSH isoforms reveals a nonglycosylated beta-subunit in addition to the conventional glycosylated beta-subunit.  

PubMed

Human FSH consists of a mixture of isoforms that can be separated on the basis of differences in negative charge conferred by variations in the numbers of sialic acid residues that terminate oligosaccharide branches. Western analysis of human FSH isoforms separated by chromatofocusing revealed the presence of two human FSHbeta isoforms that differed in size. A low mol wt human FSHbeta isoform was associated with all FSH isoform fractions. A high mol wt human FSHbeta isoform was associated with the more acidic fractions and increased in relative abundance as the pI decreased. Characterization of representative human FSHbeta isoforms by mass spectrometry and automated Edman degradation revealed a low mol wt isoform that was not glycosylated. A high mol wt isoform was N-glycosylated at Asn residues 7 and 24. These results indicate that pituitary human FSH consists of two classes of molecules: those that possess a nonglycosylated beta-subunit and those that possess a glycosylated beta-subunit. Glycoprotein hormones are known to be elliptical molecules, and the beta-subunit oligosaccharides project outward from the short diameter, thereby increasing it. It is interesting to speculate that this change in shape might affect ultrafiltration rates, leading to differences in delivery rates to target tissues and elimination by filtration in the kidney. PMID:11502795

Walton, W J; Nguyen, V T; Butnev, V Y; Singh, V; Moore, W T; Bousfield, G R

2001-08-01

79

The clomiphene citrate challenge test (CCCT) in women with elevated basal FSH: Biological significance and predictive value  

Microsoft Academic Search

ObjectiveThe rationale of the clomiphene citrate challenge test (CCCT) is that day 10 serum FSH is influenced by the quality of the recruited oocytes. Biological evidence supporting this assumption is, however, lacking. The aim of this study is to investigate the relationship between results from the CCCT and the quantity and the quality of the recruited oocytes.

Guido Ragni; Francesca Chiaffarino; Claudia Scarduelli; Silvia Bonetti; Anna Elisa Nicolosi; Mariangela Arnoldi; Edgardo Somigliana

2008-01-01

80

Effect of naloxone on the plasma levels of LH, FSH, prolactin and testosterone in Beetal bucks.  

PubMed

Ten adult male Beetal goats were used for the study to elucidate the modulation of gonadotrophin, prolactin and testosterone secretion by endogenous opioid peptides. An indwelling catheter was placed in the jugular vein of each buck 20h before the onset of the experiment. Bucks were divided randomly into two groups: Group I (n=5) received naloxone at a dose rate of 1mg/kg body weight (BW) and Group II (n=5) received naloxone at a dose rate of 2mg/kg BW intravenous. Blood samplings were done from 2h before treatment until 2h after treatment at 15min intervals. Blood samples were quantified for plasma LH, FSH and prolactin concentration using a heterologous double antibody radioimmunoassay (RIA) and testosterone concentration was quantified by coat-a-count RIA kit. The mean plasma LH levels during pretreatment phase were 0.41+/-0.03ng/ml in Group I and 0.44+/-0.02ng/ml in Group II which significantly (p<0.05) increased to 0.91+/-0.05ng/ml in Group I and 1.53+/-0.07ng/ml in Group II. The mean plasma FSH levels did not show a difference in pre- and post-treatment animals in both groups. A significant (p<0.05) increase in plasma testosterone concentration was observed in both groups after naloxone treatment, whereas, a decrease (p<0.05) was observed in plasma prolactin levels after naloxone treatment. Thus, it can be concluded that endogenous opioids do play an important role in modulating plasma LH, prolactin and testosterone concentrations in male goats. PMID:10818303

Singh; Dixit; Singh; Georgie; Dixit

2000-07-01

81

RENFORCEMENT DE LA LUMINESCENCE DES SCINTILLATIONS 03B1 PAR LES CHAMPS LECTRIQUES Par JOSEPH MATTLER,  

E-print Network

758 RENFORCEMENT DE LA LUMINESCENCE DES SCINTILLATIONS 03B1 PAR LES CHAMPS �LECTRIQUES Par JOSEPH MATTLER, Laboratoire de Luminescence, Faculté des Sciences, Paris. LE JOURNAL DE PHYSIQUE ET LE RADIUM de luminescence lorsqu'on les excite par des rayons X et à une extinction lorsqu'on les excite par la

Boyer, Edmond

82

Microtexture de fibres de carbure de silicium. Etude par microscopie lectronique par transmission  

E-print Network

229 Microtexture de fibres de carbure de silicium. Etude par microscopie électronique par fibres de carbure de silicium (Nicalon) par des techniques de microscopie électronique par transmission. Nous avons montré que toutes les fibres présentent une phase de carbure de silicium microcristallisée

Paris-Sud XI, Université de

83

Par Pond Fish, Water, and Sediment Chemistry  

SciTech Connect

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

Paller, M.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wike, L.D.

1996-06-01

84

Effects of treatment with LH and FSH between 8 and 12 weeks of age on ovarian follicular development and puberty in heifers.  

PubMed

The transient increase in gonadotrophin secretion, seen in heifer calves between 6 and 20 wk of age, may be critical for early ovarian follicular growth and for initiation of sexual maturation. We treated heifers with either 3 mg of bLH (n = 5; sc) or 4 mg sc of bFSH (n = 5; sc), every other day, between 8 and 12 wk of age. During the first 17 d of treatment, bovine gonadotrophins caused a reduction in maximum antral follicle size and in numbers of large antral follicles, compared to control heifers (P < 0.05). In 4 of 5 bLH treated heifers and 3 of 5 bFSH treated heifers, the emergence of a large dominant antral follicle was delayed (P < 0.05). At 34 wk of age, follicular dynamics did not differ among groups. Serum concentrations of estradiol were decreased in bFSH and bLH treated heifers at 35 wk of age and in bFSH treated heifers at 25 wk of age compared with that of the controls. Time of first ovulation was delayed in bFSH treated heifers compared with control heifers (P < 0.05;bFSH 59.0 +/- 1.2; control 51.4 +/- 1.8; bLH 56.2 +/- 2.5 wk of age). In summary, treatment of 8-wk old heifers with gonadotrophins every other day disrupted folliculogenesis over a 17-d period, delayed first ovulation (bFSH), and decreased ovarian estradiol production at 25 (bFSH) and 35 (bLH, bFSH) weeks of age. PMID:16727770

Evans, A C; Rawlings, N C

1995-10-01

85

Differences in clinical characteristics of fallopian canal dehiscence associated with pars flaccida and pars tensa cholesteatomas.  

PubMed

This study investigated the difference in clinical characteristics of fallopian canal dehiscence associated with pars flaccida and pars tensa cholesteatomas for the purpose of increasing the preoperative detectability of dehiscence. A total of 189 ears of patients 7-80 years of age (mean 42 years) with pars flaccida cholesteatoma and 63 ears of patients 9-84 years of age (mean 50 years) with pars tensa cholesteatoma were studied. All patients had undergone prior surgical management at our institution from January 2006 to April 2012. The incidence of fallopian canal dehiscence and its location were compared between pars flaccida and pars tensa cholesteatomas. Intraoperative findings of coexistent pathologies, including destruction of the stapes superstructure, labyrinthine fistula, and dural exposure, were compared between the dehiscence and no-dehiscence groups for the two types of cholesteatomas. The incidence of dehiscence was significantly higher in patients with pars tensa cholesteatoma (55.6 %) than in patients with pars flaccida cholesteatoma (26.5 %). Dehiscence located posterior to the cochleariform process occurred slightly more frequently in patients with pars tensa cholesteatoma than in those with pars flaccida cholesteatoma. In patients with pars flaccida cholesteatoma, labyrinthine fistulas and dural exposure were significantly more frequent in the dehiscence group than in the no-dehiscence group. Fallopian canal dehiscence is more frequent in patients with pars tensa cholesteatoma than in those with pars flaccida cholesteatoma. Especially in patients with pars flaccida cholesteatoma, paying special attention to these coexisting pathologies is important to increase preoperative detectability of dehiscence. PMID:24071859

Shinnabe, Akihiro; Yamamoto, Hiroki; Hara, Mariko; Hasegawa, Masayo; Matsuzawa, Shingo; Kanazawa, Hiromi; Yoshida, Naohiro; Iino, Yukiko

2014-08-01

86

EXPRIENCES LECTROCAPILLAIRES; PAR G. LIPPMANN,  

E-print Network

vase plus large A contenant du mercure. La colonne de mercure se ter- mine en M par un ménisque convexe ioud de ce verre se trouve une couche de mercure. Deux fils de platine a, (3, isolés 1 un de Article'autre, sont en contact avec les deux masses de mercure en A et B, et permettent de les inettre en

Paris-Sud XI, Université de

87

Nocturnal and diurnal levels of prolactin, LH, FSH, estrogens, and progesterone in middle-aged, spontaneously persistent estrous rats  

Microsoft Academic Search

Reproductive research in aging animals is often performed with very old rats manifesting spontaneous persistent estrus (SPE).\\u000a However, Charles River (CD) Sprague Dawley rats present SPE as early as 6 months of age and thus are potentially very useful\\u000a in such studies since the concomitant pathologies associated with old age can be avoided. Serum levels of LH, FSH, prolactin,\\u000a estrogens,

Judith E. Beach; Lee Tyrey; David W. Schombergl; John W. Everett

1983-01-01

88

Photoperiod-gonadotropin mismatches induced by treatment with acyline or FSH in Siberian hamsters: impacts on ovarian structure and function.  

PubMed

Many seasonal breeders time their reproductive efforts to specific times of the year to ensure adequate resources for the production and care of young. For long-day (LD) breeders, females born before the summer solstice (LDs) reach sexual maturity quickly and often breed that same year, whereas females born after the summer solstice (short days (SDs)) may delay reproductive development to the following spring when environmental conditions are favorable for reproduction. In Siberian hamsters, development in SD is associated with structural and functional differences in the ovary compared with females held in LD, including a greater number of primordial follicles and an abundance of hypertrophied granulosa cells (HGCs), which are immunoreactive for anti-Müllerian hormone. The goal of this study was to determine whether SD-induced gonadotropin suppression is responsible for these phenotypic differences. Gonadotropin levels were suppressed in LD hamsters using the GNRH antagonist acyline. Conversely, to determine whether the SD ovarian phenotype is completely reversed by gonadotropin stimulation, recombinant human FSH (rhFSH) was administered. Our treatments were successful in mimicking FSH concentrations of the opposite photoperiod, but they did not produce a comparable change in the ovarian phenotype. Most notable was the lack of HGCs in the ovaries of acyline-treated LD females. Similarly, HGCs were maintained in the ovaries of SD females treated with rhFSH. Our data suggest that gonadotropins alone do not account for the SD ovarian phenotype. Future studies will determine whether SD-induced changes in other factors underlie these phenotypic changes. PMID:22936286

Zysling, D A; Park, S-U; McMillan, E L; Place, N J

2012-11-01

89

Pueraria tuberosa DC Extract Improves Androgenesis and Sexual Behavior via FSH LH Cascade  

PubMed Central

The aim of this study was to investigate the effects of ethanolic extract of Pueraria tuberosa (PT) on sexual behaviour and androgenic activity. Male albino rats were divided into four groups of six animals each: control group 1 (2% acacia solution), PT-treated group 2 (50?mg/Kg), PT-treated group 3 (100?mg/Kg), and PT-treated group 4 (150?mg/Kg). Sexual behavior of male rats in the presence of a female rat was recorded. The treated groups were evaluated for sexual parameters. The extract was characterized using LC-MS. The effect of treatment on anabolic and weight of secondary sexual organs was determined. The histological changes in section of testis and epididymis after treatment were observed. Sperm count in epididymis and fructose content in seminal vesicles were also measured. Levels of hormones like FSH, LH, and T were determined. A dose-dependent increase in sexual behaviors was evidenced in the animals of extract treated groups. Increase in testis weight was recorded in PT. At the highest dose PT also affects the hormones level. The four compounds namely puerarin, daidzein, biochanin-A and formononetin were identified in ethanolic extract using LC-MS. It concluded that PT extract possesses androgenic effect and it significantly increased the sexual behaviour and hormones level. PMID:24489512

Chauhan, Nagendra Singh; Sharma, Vikas; Christine Helena Frankland Sawaya, Alexandra; Dixit, V. K.

2013-01-01

90

FOXO1/3 Depletion in Granulosa Cells Alters Follicle Growth, Death and Regulation of Pituitary FSH  

PubMed Central

The Forkhead boxO (FOXO) transcription factors regulate multiple cellular functions. FOXO1 and FOXO3 are highly expressed in granulosa cells of ovarian follicles. Selective depletion of the Foxo1 and Foxo3 genes in granulosa cells of mice reveals a novel ovarian-pituitary endocrine feedback loop characterized by: 1) undetectable levels of serum FSH but not LH, 2) reduced expression of the pituitary Fshb gene and its transcriptional regulators, and 3) ovarian production of a factor(s) that suppresses pituitary cell Fshb expression. Equally notable, and independent of FSH, microarray analyses and quantitative PCR document that depletion of Foxo1/3 alters the expression of specific genes associated with follicle growth vs. apoptosis by disrupting critical and selective regulatory interactions of FOXO1/3 with the activin or bone morphogenetic protein 2 (BMP2) pathways, respectively. As a consequence, both granulosa cell proliferation and apoptosis were decreased. These data provide the first evidence that FOXO1/3 divergently regulate follicle growth or death by interacting with the activin or BMP pathways in granulosa cells and by modulating pituitary FSH production. PMID:23322722

Liu, Zhilin; Castrillon, Diego H.; Zhou, Wei

2013-01-01

91

A selective monotropic elevation of FSH, but not that of LH, amplifies the proliferation and differentiation of spermatogonia in the adult rhesus monkey (Macaca mulatta)  

PubMed Central

BACKGROUND Unilateral orchidectomy in monkeys increases spermatogenesis in the remaining testis in association with elevated follicle-stimulating hormone (FSH) secretion and testicular testosterone. The present study examined the relative importance of FSH and testosterone in driving the primate testis toward its spermatogenic ceiling. METHODS Adult male rhesus monkeys were treated with a gonadotropin-releasing hormone receptor antagonist to inhibit endogenous FSH and luteinizing hormone (LH) secretion. The gonadotrophin drive to the testis was replaced with a pulsatile recombinant human FSH and LH infusion to maintain testicular volume and circulating testosterone and inhibin B at physiological levels. A selective monotropic elevation of FSH or LH that doubled the concentrations of inhibin B or testosterone, respectively, was then imposed for 4 weeks, each in a group of four monkeys. In a third group (n = 4), the gonadotrophin drive remained clamped at physiological levels. Bromo-deoxyuridine was administered 3 h prior to castration, and the effects of the monotropic hormone increments on germ cell number, S-phase labeling and degeneration were determined. RESULTS Increased FSH, but not LH, produced increases in testicular volume (P < 0.05), the proportion of A pale spermatogonia entering the cell cycle and the numbers of differentiated spermatogonia and more advanced germ cells (P < 0.05). Indexes for spermatogonia labeling and germ cell degeneration were not affected. CONCLUSIONS Under physiological conditions, circulating concentrations of FSH directly dictate sperm output of the primate testis by regulating the proportion of Ap spermatogonia in the growth fraction. An effect of FSH on survival of the first generation of differentiated B spermatogonia is not excluded. PMID:19279035

Simorangkir, D.R.; Ramaswamy, S.; Marshall, G.R.; Pohl, C.R.; Plant, T.M.

2009-01-01

92

The gonadotropin receptors FSH-R and LH-R of Atlantic halibut (Hippoglossus hippoglossus)--2. Differential follicle expression and asynchronous oogenesis.  

PubMed

The biological activity and spatio-temporal expression patterns of the gonadotropin receptors FSH-R and LH-R were examined in the repetitive spawner Atlantic halibut to elucidate the gonadotropic regulation of the asynchronous follicle development. The cloned receptors were expressed in mammalian COS-7 cells, and stimulation with sea bass FSH and LH increased the cAMP production. The halibut FSH-R and LH-R genes were shown to be highly expressed in the gonads of sexually mature fish, but the transcripts were also found in extra-gonadal tissues such as pituitary and brain. Different expression patterns of FSH-R and LH-R in the developing follicles were documented by semi-quantitative RT-PCR. Abundant FSH-R mRNA was found in the small follicles during primary growth and vitellogenesis, and the signals were localized to the granulosa cells by in situ hybridization. In contrast, follicular LH-R mRNA was hardly detectable during the early stages. Conversely, in follicles during final maturation FSH-R mRNA levels tended to decrease, while the expression of LH-R was highly upregulated. Whereas the pituitary FSH and LH are asynchronously expressed in annual spawners, both gonadotropins were expressed in the female halibut pituitary throughout the reproductive cycle, except in the prespawning females. Hence, the sequential gonadotropic activation of ovarian follicle growth and maturation in repetitive spawners is probably regulated by modulating the temporal expression of FSH-R and LH-R in the follicle membrane. PMID:18377904

Kobayashi, Tamae; Pakarinen, Pirjo; Torgersen, Jacob; Huhtaniemi, Ilpo; Andersen, Øivind

2008-05-01

93

A randomized, double-blind clinical trial using fixed daily doses of 100 or 200 IU of recombinant FSH in ICSI cycles  

Microsoft Academic Search

The effect of 100 and 200 IU per day recombinant FSH (rFSH) on numbers of oocytes retrieved and the total dose used in ovarian stimulation before intracytoplasmic sperm injection was investigated in a double-blind, randomized multicentre trial. A total of 91 women was treated with a low-dose protocol and 88 with a high-dose regimen at five centres. For each started

Ishay David; Raphael Ron-El; Shevach Friedler; Eliezer Shalev; Joel Geslevich; Jehoshua Dor; Adrian Shulman; Zion Ben-Rafael; Benjamin Fisch; Martha Dirnfeld

94

Equine pituitary pars intermedia dysfunction.  

PubMed

Equine pituitary pars intermedia dysfunction (PPID), also known as equine Cushing's syndrome, is a widely recognized disease of aged horses. Over the past two decades, the aged horse population has expanded significantly and in addition, client awareness of PPID has increased. As a result, there has been an increase in both diagnostic testing and treatment of the disease. This review focuses on the pathophysiology and clinical syndrome, as well as advances in diagnostic testing and treatment of PPID, with an emphasis on those findings that are new since the excellent comprehensive review by Schott in 2002. PMID:21392656

McFarlane, Dianne

2011-04-01

95

Estrus response and follicular development in Boer does synchronized with flugestone acetate and PGF2? or their combination with eCG or FSH.  

PubMed

The effects of different estrus synchronization techniques on follicular development and estrus response were studied in 81 nulliparous Boer does. The does were divided into nine groups. Eight of the nine groups were synchronized with prostaglandin F2-alpha (PGF(2?)) or flugestone acetate (FGA) or their combinations, and the ninth group was a control group. In addition to the above combinations, four of the eight synchronized groups were given 5 mg follicle-stimulating hormone (FSH) and the remaining four groups were administered 300 IU equine chorionic gonadotrophin (eCG). Posttreatment follicular development was monitored until ovulation occurred using a real-time B-mode ultrasound scanner (Aloka, 500 SSD, Japan), with a 7.5-MHz transrectal linear probe. All the does from the synchronized groups that were given eCG exhibited oestrus while only 88.9% of the does synchronized with FSH showed estrus. The estrus response was observed to be the least among the does synchronized with PGF(2?) + FSH (33.3%) combination followed closely by the FGA + FSH (42.9%) combinations. It was observed that the combinations of FGA + PGF(2?) + FSH resulted in increased percentage of estrus response, duration of estrus, and ovulation. The number of follicles was higher (P < 0.05) in FSH-synchronized groups than the eCG-synchronized groups. It was concluded that the best estrus synchronization protocol in goats is the FGA + eCG with or without PGF(2?). However, the PGF(2?) + FGA + FSH method of estrus synchronization is the most promising combination for further development as a better alternative to estrus synchronization with eCG in does. PMID:22461200

Bukar, Muhammad Modu; Yusoff, Rosnina; Haron, Abd Wahid; Dhaliwal, Gurmeet Kaur; Khan, Mohd Azam Goriman; Omar, Mohammed Ariff

2012-10-01

96

Par Pond vegetation status Summer 1995 -- Summary  

SciTech Connect

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

Mackey, H.E. Jr.; Riley, R.S.

1996-01-01

97

Article original Infection par la chlamydiose aviaire  

E-print Network

plus infectés (17,8%) que les pigeons des autres races (2,5%) en Nouvelle-Calédonie (PArticle original Infection par la chlamydiose aviaire chez les pigeons d'élevage en Nouvelle chlamydiose aviaire, par sondage sérologique chez 8 éleveurs de pigeons représentatifs du cheptel néo

Boyer, Edmond

98

Segrosome assembly at the pliable parH centromere  

PubMed Central

The segrosome of multiresistance plasmid TP228 comprises ParF, which is a member of the ParA ATPase superfamily, and the ParG ribbon–helix–helix factor that assemble jointly on the parH centromere. Here we demonstrate that the distinctive parH site (?100-bp) consists of an array of degenerate tetramer boxes interspersed by AT-rich spacers. Although numerous consecutive AT-steps are suggestive of inherent curvature, parH lacks an intrinsic bend. Sequential deletion of parH tetramers progressively reduced centromere function. Nevertheless, the variant subsites could be rearranged in different geometries that accommodated centromere activity effectively revealing that the site is highly elastic in vivo. ParG cooperatively coated parH: proper centromere binding necessitated the protein's N-terminal flexible tails which modulate the centromere binding affinity of ParG. Interaction of the ParG ribbon–helix–helix domain with major groove bases in the tetramer boxes likely provides direct readout of the centromere. In contrast, the AT-rich spacers may be implicated in indirect readout that mediates cooperativity between ParG dimers assembled on adjacent boxes. ParF alone does not bind parH but instead loads into the segrosome interactively with ParG, thereby subtly altering centromere conformation. Assembly of ParF into the complex requires the N-terminal flexible tails in ParG that are contacted by ParF. PMID:21378121

Wu, Meiyi; Zampini, Massimiliano; Bussiek, Malte; Hoischen, Christian; Diekmann, Stephan; Hayes, Finbarr

2011-01-01

99

Superovulation in ewes by a single injection of pFSH dissolved in polyvinylpyrrolidone (PVP): effects of PVP molecular weight, concentration and schedule of treatment.  

PubMed

Three experiments were carried out to evaluate induction in ewes of superovulation and embryo production by a single injection of a porcine pituitary extract (pFSH) dissolved in polyvinylpyrrolidone (PVP), investigating the effects of PVP molecular weight and its concentration (Experiment I), time and method of treatment (Experiments II and III). All ewes were synchronized for estrus by vaginal sponges impregnated with fluorogestone acetate (FGA; 30 mg, 9 days) plus PGF(2alpha) (Cloprostenol, 50 microg, 48h before sponge removal - s.r.), and superovulated by 250 IU pFSH. In Experiment I, 60 Gentile di Puglia ewes were subdivided into five experimental groups (n = 12): Group A, the control, received six decreasing intramuscular (i.m.) doses of pFSH, 12 h apart, beginning 48h before s.r.; Groups B and C were given 48 h before s.r. a single i.m. injection of pFSH dissolved in PVP with MW = 10,000, respectively, at concentrations of 15 and 30% w/v; Groups D and E received the same treatments as for B and C using PVP with MW = 40,000. None of the pFSH-PVP treatments were effective in inducing superovulation. In Experiment II, 22 Leccese ewes were subdivided into two groups (n = 11): Group A, control received i.m. four decreasing doses of pFSH, beginning 24 h before s.r., 12h apart; Group B was given a single i.m. injection of pFSH dissolved in PVP (MW = 40,000 at 30% w/v), 24 h before s.r. The pFSH-PVP treatment provided an ovulation rate similar to the control and tended to enhance embryo yield (4.4 versus 2.4, P>0.05). In Experiment III, 60 Leccese ewes were subdivided into six treatment groups (n = 10). Groups A and D served as controls and received i.m. 12 h apart, six doses (from 48 h before s.r.) and four doses (from 24h before s.r.) of pFSH, respectively. Groups B and C were treated by a single injection of pFSH in PVP (MW = 10,000; 30% w/v) 48 h before s.r., respectively by i.m. or subcutaneous (s.c.) administration. Groups E and F received the same treatments as for B and C 24 h before s.r. Intramuscular pFSH-PVP administration 24 h before s.r. provided an ovulation rate (8.1), mean numbers of ova recovered (5.6) and fertilized (4.2) comparable to the six or four dose treatments and significantly higher (P <0.01) compared to the pFSH-PVP treatment carried out i.m. 48 h before s.r. These results show that a single injection of pFSH dissolved in PVP at 30% w/v, performed i.m. 24 h before s.r., is able to induce a superovulatory response comparable to that following multiple injection treatment, regardless of PVP molecular weight. PMID:11267805

D'Alessandro, A G; Martemucci, G; Colonna, M A; Borghese, A; Terzano, M G; Bellitti, A

2001-03-30

100

Effects of treatment with LH or FSH from 4 to 8 weeks of age on the attainment of puberty in bull calves.  

PubMed

A transient increase in gonadotropin secretion between 6 and 20 weeks of age is critical for the onset of puberty in bull calves. To try and hasten the onset of puberty, bull calves were treated (s.c.) with 3 mg of bLH (n = 6) or 4 mg of bFSH (n = 6) once every 2 days, from 4 to 8 weeks after birth; control calves received saline (n = 6). At 4 and 8 weeks of age, mean LH concentrations were higher (P < 0.05) in bLH-treated (2.3 +/- 0.04 ng/ml and 1.20 +/- 0.04 ng/ml) as compared to control calves (0.50 +/- 0.1 ng/ml and 0.70 +/- 0.10 ng/ml). Mean serum FSH concentrations at 4 and 8 weeks of age, were higher (P < 0.05) in bFSH-treated (1.60 +/- 0.20 ng/ml and 1.10 +/- 0.2 ng/ml) as compared to control calves (0.38 +/- 0.07 ng/ml and 0.35 +/- 0.07 ng/ml). The age at which scrotal circumference (SC) first reached > or = 28 cm, occurred earlier (P < 0.05) in bFSH-treated calves as compared to saline-treated calves (39.3 +/- 1.3 and 44.8 +/- 1.3 weeks of age, respectively). Based on testicular histology at 56 weeks of age, treatment with bFSH resulted in greater (P < 0.05) numbers of Sertoli cells (5 +/- 0.2, 6 +/- 0.3 and 5 +/- 0.3 in bLH-, bFSH- and saline-treated calves, respectively); elongated spermatids (42 +/- 2, 57 +/- 8 and 38 +/- 5 in bLH-, bFSH- and saline-treated calves, respectively) and spermatocytes (31 +/- 3, 38 +/- 3 and 29 +/- 2 in bLH-, bFSH- and saline-treated calves, respectively) per seminiferous tubule. We concluded that treatment of bull calves with bFSH from 4 to 8 weeks of age increased testicular growth (SC); hastened onset of puberty (SC > or = 28 cm); and enhanced spermatogenesis. PMID:15251238

Bagu, E T; Madgwick, S; Duggavathi, R; Bartlewski, P M; Barrett, D M W; Huchkowsky, S; Cook, S J; Rawlings, N C

2004-09-01

101

Calcineurin and CRTC2 mediate FSH and TGF?1 upregulation of Cyp19a1 and Nr5a in ovary granulosa cells.  

PubMed

Estrogens are essential for female reproduction and overall well-being, and estrogens in the circulation are largely synthesized in ovarian granulosa cells. Using primary cultures of ovarian granulosa cells from gonadotropin-primed immature rats, we have recently discovered that pituitary FSH and ovarian cytokine transforming growth factor beta 1 (TGF?1) induce calcineurin-mediated dephosphorylation-activation of cAMP-response element-binding protein (CREB)-regulated transcription coactivator (CRTC2) to modulate the expression of Star, Cyp11a1, and Hsd3b leading to increased production of progesterone. This study explored the role of calcineurin and CRTC2 in FSH and TGF?1 regulation of Cyp19a1 expression in granulosa cells. Ovarian granulosa cells treated with FSH displayed increased aromatase protein at 24 ?h post-treatment, which subsided by 48 ?h, while TGF?1 acting through its type 1 receptor augmented the action of FSH with a greater and longer effects. It is known that the ovary-specific Cyp19a1 PII-promoter contains crucial response elements for CREB and nuclear receptor NR5A subfamily liver receptor homolog 1 (LRH1/NR5A2) and steroidogenic factor 1 (SF1/NR5A1), and that the Nr5a2 promoter also has a potential CREB-binding site. Herein, we demonstrate that FSH+TGF?1 increased LRH1 and SF1 protein levels, and their binding to the Cyp19a1 PII-promoter evidenced, determined by chromatin immunoprecipitation analysis. Moreover, pretreatment with calcineurin auto-inhibitory peptide (CNI) abolished the FSH+TGF?1-upregulated but not FSH-upregulated aromatase activity at 48 ?h, and the corresponding mRNA changes in Cyp19a1, and Nr5a2 and Nr5a1 at 24 ?h. In addition, FSH and TGF?1 increased CRTC2 binding to the Cyp19a1 PII-promoter and Nr5a2 promoter at 24? h, with CREB bound constitutively. In summary, the results of this study indicate that calcineurin and CRTC2 have important roles in mediating FSH and TGF?1 collateral upregulation of Cyp19a1 expression together with its transcription regulators Nr5a2 and Nr5a1 in ovarian granulosa cells. PMID:25057110

Lai, Wei-An; Yeh, Yi-Ting; Fang, Wei-Ling; Wu, Leang-Shin; Harada, Nobuhiro; Wang, Peng-Hui; Ke, Ferng-Chun; Lee, Wen-Ling; Hwang, Jiuan-Jiuan

2014-10-01

102

E{Java, CaesarJ, Scala} : un exercice d'integration de la programmation par objets, par aspects et par ev`enements  

E-print Network

E{Java, CaesarJ, Scala} : un exercice d'int´egration de la programmation par objets, par aspects et.Noye@mines-nantes.fr R´esum´e La programmation par ´ev`enements et la programmation par aspects sont des paradigmes de programmation qui s'av`erent compl´eter utilement la programmation par objets dans une tr`es large gamme d

Paris-Sud XI, Université de

103

Onset of lipoprotein-supported steroidogenesis in differentiating granulosa cells of rats: cellular events involved in mediating FSH-enhanced uptake of low-density lipoproteins  

SciTech Connect

Luteal cells use lipoproteins as the main source of cholesterol in steroidogenesis. However, little is known about the mechanisms underlying hormonal control of lipoprotein uptake. Thus, the authors tested the hypothesis that FSH and androgens regulate low density lipoprotein (LDL)-supported steroidogenesis in maturing granulosa cells by affecting receptor-mediated endocytosis of LDL at a cellular level. For this, immature ovarian granulosa cells were cultured with or without hormones, compactin (de novo synthesis inhibitor), or unlabeled or labeled (/sup 125/I or gold particles) LDL. Nonhormone-treated cultures produced little progestin; FSH and FSH/androstenedione stimulated steroid secretion. Progestin production by hormone-, but not nonhormone-, treated cultures was decreased by compactin, suggesting that de novo synthesis provided sterol for steroidogenesis. EM quantitation of cells exposed to gold-LDL at 37/sup 0/C revealed that, compared to nonhormone-treated cells, FSH-treated cells (1) bound and internalized more gold-LDL, (2) had a smaller percentage of gold-LDL at their surfaces, (3) displayed a faster apparent rate of LDL internalization and delivery to lysosomes, and (4) contained more gold-labeled lysosomes. Data from biochemical studies in which /sup 125/I-LDL was used supported the morphological findings. In conclusion, this study demonstrates that FSH has important effects at the cellular level on LDL uptake, which seem to underlie the striking increase in progestin production accompanying granulosa cell differentiation.

Foster, J.D.

1987-01-01

104

Different pharmacokinetic and pharmacodynamic properties of recombinant follicle-stimulating hormone (rFSH) derived from a human cell line compared with rFSH from a non-human cell line.  

PubMed

Pharmacokinetic and pharmacodynamic properties of a novel recombinant follicle-stimulating hormone (rFSH) preparation (FE 999049), expressed by a human cell line (PER.C6), was compared with an rFSH preparation (follitropin ?) expressed by a Chinese hamster ovary (CHO) cell line in healthy pituitary-suppressed women. Following single intravenous administration of 225 IU (Steelman-Pohley assay), the clearance was lower, 0.31 versus 0.44 L/h, for FE 999049 than for follitropin ?. Likewise, the apparent clearance after repeated daily subcutaneous administrations was lower, 0.58 versus 0.99 L/h, and AUC and Cmax higher, 1.7- and 1.6-fold. The absolute bioavailability after a single subcutaneous dose of 450 IU was similar for both preparations, 60-65%. After repeated subcutaneous administration the elimination half-life was approximately 30 and 24 hours for FE 999049 and follitropin ?. The ovarian responses by number of follicles and serum concentrations of inhibin B and estradiol, were higher with FE 999049 than with follitropin ?, AUC and Cmax for the two latter being >1.6-fold greater with FE 999049 than with follitropin ?. These results indicate that administration of equal doses of FE 999049, expressed in a human cell line, and follitropin ?, expressed in a CHO cell line, display different pharmacokinetic and pharmacodynamic properties in humans. PMID:24800998

Olsson, Håkan; Sandström, Rikard; Grundemar, Lars

2014-11-01

105

An unbalanced translocation unmasks a recessive mutation in the follicle-stimulating hormone receptor (FSHR) gene and causes FSH resistance  

PubMed Central

Follicle-stimulating hormone (FSH) mediated by its receptor (FSHR) is pivotal for normal gametogenesis. Inactivating FSHR mutations are known to cause hypergonadotropic hypogonadism with disturbed follicular maturation in females. So far, only very few recessive point mutations have been described. We report on a 17-year-old female with primary amenorrhea, hypergonadotropic hypogonadism and disturbed folliculogenesis. Chromosome analysis detected a seemingly balanced translocation 46,XX,t(2;8)(p16.3or21;p23.1)mat. FSHR sequence analysis revealed a novel non-synonymous point mutation in exon 10 (c.1760C>A, p.Pro587His), but no wild-type allele. The mutation was also found in the father, but not in the mother. Furthermore, molecular-cytogenetic analyses of the breakpoint region on chromosome 2 showed the translocation to be unbalanced, containing a deletion with one breakpoint within the FSHR gene. The deletion size was narrowed down by array analysis to approximately 163?kb, involving exons 9 and 10 of the FSHR gene. Functional studies of the mutation revealed the complete lack of signal transduction presumably caused by a changed conformational structure of transmembrane helix 6. To our knowledge, this is the first description of a compound heterozygosity of an inactivating FSHR point mutation unmasked by a partial deletion. This coincidence of two rare changes caused clinical signs consistent with FSH resistance. PMID:20087398

Kuechler, Amla; Hauffa, Berthold P; Koninger, Angela; Kleinau, Gunnar; Albrecht, Beate; Horsthemke, Bernhard; Gromoll, Jorg

2010-01-01

106

Proteinase-activated receptor-1 (PAR1) and PAR2 mediate relaxation of guinea pig internal anal sphincter.  

PubMed

Activation of proteinase-activated receptor-1 (PAR1) and PAR2 stimulates contraction of the rat but relaxation of the guinea pig colon. The aim of the present study was to investigate PAR effects on internal anal sphincter (IAS) motility. We measured relaxation of isolated muscle strips from the guinea pig IAS caused by PAR agonists using isometric transducers. Reverse transcription polymerase chain reaction (RT-PCR) was performed to determine the existence of PAR. In the IAS, thrombin and PAR1 peptide agonists TFLLR-NH2 and SFLLRN-NH2 evoked moderate to marked relaxation in a concentration-dependent manner. In addition, trypsin and PAR2 peptide agonists 2-furoyl-LIGRLO-NH2, SLIGRL-NH2 and SLIGKV-NH2 produced relaxation. In contrast, both PAR1 and PAR2 inactive control peptides did not elicit relaxation. Furthermore, the selective PAR1 antagonist vorapaxar and PAR2 antagonist GB 83 specifically inhibited thrombin and trypsin-induced relaxations, respectively. RT-PCR revealed the presence of PAR1 and PAR2 in the IAS. This indicates that PAR1 and PAR2 mediate the IAS relaxation. The relaxant responses of TFLLR-NH2 and trypsin were attenuated by N(omega)-Nitro-L-arginine (L-NNA), indicating involvement of NO. These responses were not affected by tetrodotoxin, implying that the PAR effects are not neurally mediated. On the other hand, PAR4 agonists GYPGKF-NH2, GYPGQV-NH2 and AYPGKF-NH2 did not cause relaxation or contraction, suggesting that PAR4 is not involved in the sphincter motility. Taken together, these results demonstrate that both PAR1 and PAR2 mediate relaxation of the guinea pig IAS through the NO pathway. PAR1 and PAR2 may regulate IAS tone and might be potential therapeutic targets for anal motility disorders. PMID:24631471

Huang, Shih-Che

2014-02-10

107

Plasma FSH, inhibin A and inhibin isoforms containing pro- and -alphaC during winter anoestrus, spring transition and the breeding season in mares.  

PubMed

Ten mares were studied from February (winter anoestrus) to their second ovulation in the breeding season to investigate the relationship between resumption of ovarian cyclicity in the spring and circulating concentrations of FSH, inhibin A and inhibin isoforms containing pro- and -alphaC immunoreactivity. An additional four mares were studied during one oestrous cycle. Growth and regression of ovarian follicles were monitored by transrectal ultrasonography. The frequency of blood sampling varied from three times a week to once a day, depending on the follicular activity present. Concentrations of FSH, oestradiol, inhibin A and pro- and -alphaC isoforms were low during deep winter anoestrus when minimal follicular activity was present in the ovaries. During spring transition, an increase in FSH concentration preceded the emergence of each follicular wave. Concentrations of inhibins were significantly higher (P < 0.05) during growth of anovulatory follicles in spring transition than during winter anoestrus. Plasma concentrations of oestradiol and inhibin A were significantly higher (P < 0.001, P < 0.05, respectively) during the growth of preovulatory follicles than during the growth of transitional anovulatory follicles, but concentrations of inhibin pro-alphaC isoforms did not differ between the two types of follicle. During the oestrous cycle, there was a significant inverse relationship (P < 0.001) between concentrations of FSH and the inhibins. Plasma inhibin pro-alphaC isoforms, but not inhibin A, reached a peak on the day of ovulation. The results strongly indicate that FSH regulates growth of spring anovulatory and preovulatory follicles. Inhibins are likely to contribute to negative feedback on the release of FSH from the pituitary gland both during the transitional period and the breeding season in mares. PMID:11914116

Watson, E D; Heald, M; Tsigos, A; Leask, R; Steele, M; Groome, N P; Riley, S C

2002-04-01

108

Oxydation du silicium par bombardement lectronique. Influence de la pollution par le carbone (+)  

E-print Network

151 Oxydation du silicium par bombardement électronique. Influence de la pollution par le carbone, accepté le 26 novembre 1984) Résumé. 2014 L'oxydation du silicium monocristallin a été effectuée par'oxygène sec, 3) en présence d'un flux constant d'oxygène sec dans l'enceinte à vide. Les oxydes sont analysés

Paris-Sud XI, Université de

109

PAR -- Interface to the ADAM Parameter System  

NASA Astrophysics Data System (ADS)

PAR is a library of Fortran subroutines that provides convenient mechanisms for applications to exchange information with the outside world, through input-output channels called parameters. Parameters enable a user to control an application's behaviour. PAR supports numeric, character, and logical parameters, and is currently implemented only on top of the ADAM parameter system. The PAR library permits parameter values to be obtained, without or with a variety of constraints. Results may be put into parameters to be passed onto other applications. Other facilities include setting a prompt string, and suggested defaults. This document also introduces a preliminary C interface for the PAR library -- this may be subject to change in the light of experience.

Currie, Malcolm J.; Chipperfield, Alan J.

110

Radioecological implications of the Par Pond drawdown  

SciTech Connect

The drawdown of the Par Pond reservoir created dramatic alterations in this formerly stable lentic ecosystem. In addition, the radiation environment at Par Pond has changed significantly because of the exposure of Cesium 137-contaminated sediments and the appearance of new transport pathways to the terrestrial environment. In response to this situation, SREL was asked to study the radioecological implications of the reservoir drawdown. This report contains the objectives, methods, and results of the SREL study.

Hickey, H. [Westinghouse Savannah River Co., Aiken, SC (United States); Whicker, F.W. [Savannah River Ecology Lab., Aiken, SC (United States)

1991-12-05

111

Maladies émergentes transmises par les tiques  

Microsoft Academic Search

RésuméLes infections transmises par les tiques surviennent dans le monde entier et sont bien connues depuis plus d’un siècle. Certaines d’entre elles sont très courantes alors que d’autres sont extrêmement rares. Les techniques modernes de génétique moléculaire (dont une plus grande disponibilité de la réaction en chaîne par polymérase (PCR) (de l’anglais polymerase chain reaction) ont permis la découverte et

Ingomar Mutz

2009-01-01

112

POMPE A MERCURE AUTOMATIQUE : Par M. KLEIN.  

E-print Network

293 POMPE A MERCURE AUTOMATIQUE : Par M. KLEIN. Cette pompe à mercure est actionnéepar une trompe à, comme les an- ciennes pompes à remontage à la main, une boule-pompe etun réci- pient à mercure. Mais, au reliée à une trompe à eau et, au lieu que les déplacements du mercure soient produits par les

Paris-Sud XI, Université de

113

ATP-regulated interactions between P1 ParA, ParB and non-specific DNA that are stabilized by the plasmid partition site, parS  

PubMed Central

Localization of the P1 plasmid requires two proteins, ParA and ParB, which act on the plasmid partition site, parS. ParB is a site-specific DNA-binding protein and ParA is a Walker-type ATPase with non-specific DNA-binding activity. In vivo ParA binds the bacterial nucleoid and forms dynamic patterns that are governed by the ParB–parS partition complex on the plasmid. How these interactions drive plasmid movement and localization is not well understood. Here we have identified a large protein–DNA complex in vitro that requires ParA, ParB and ATP, and have characterized its assembly by sucrose gradient sedimentation and light scattering assays. ATP binding and hydrolysis mediated the assembly and disassembly of this complex, while ADP antagonized complex formation. The complex was not dependent on, but was stabilized by, parS. The properties indicate that ParA and ParB are binding and bridging multiple DNA molecules to create a large meshwork of protein–DNA molecules that involves both specific and non-specific DNA. We propose that this complex represents a dynamic adaptor complex between the plasmid and nucleoid, and further, that this interaction drives the redistribution of partition proteins and the plasmid over the nucleoid during partition. PMID:21965538

Havey, James C.; Vecchiarelli, Anthony G.; Funnell, Barbara E.

2012-01-01

114

Effects of transdermal testosterone application on the ovarian response to FSH in poor responders undergoing assisted reproduction technique--a prospective, randomized, double-blind study  

Microsoft Academic Search

BACKGROUND: In primates, androgens can play a synergistic role with FSH in promoting the early follicular recruitment, which is critical in assisted reproduction technique programmes. OBJECTIVE: To assess whether poor responders can benefit from androgen application. METHODS: Inclusion criteria were a previous poor ovarian response to controlled ovarian stimulation and a decreased hormonal ovarian reserve. Selected women were rand- omized

N. Massin; I. Cedrin-Durnerin; C. Coussieu; J. Galey-Fontaine; J. P. Wolf; J.-N. Hugues

2006-01-01

115

Sexually dimorphic expression of gonadotropin subunits in the pituitary of protogynous honeycomb grouper (Epinephelus merra): evidence that follicle-stimulating hormone (FSH) induces gonadal sex change.  

PubMed

Recent studies have suggested that the hypothalamic-pituitary-gonadal axis is involved in gonadal sex change in sex-changing teleosts. However, its underlying mechanism remains largely unknown. In this study, we focused on the distinct roles of two gonadotropins (GTHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), in the protogynous hermaphrodite teleost, honeycomb grouper (Epinephelus merra). First, we investigated the expression pattern of mRNAs for GTH subunits (cga, fshb, and lhb) in the pituitaries from fish at the different sexual phases. Real-time RT-PCR analyses showed that fhsb mRNA levels in the female pituitary were low. However, fshb transcripts increased dramatically in association with testis development. In contrast, levels of cga and lhb mRNAs did not significantly vary during sex change. In addition, immunohistochemical observations of Fshb- and Lhb-producing cells in the pituitary, through the use of specific antibodies for detections of teleost GTH subunits, were consistent with sexually dimorphic expression of Fshb. In order to identify the role of GTH in gonad of honeycomb grouper, we treated females with bovine FSH (50 or 500 ng/fish) or LH (500 ng/fish) in vivo. After 3 wk, FSH treatments induced female-to-male sex change and up-regulated endogenous androgen levels and fshb transcripts, whereas LH treatment had no effect on sex change. These results suggest that FSH may trigger the female-to-male sex change in honeycomb grouper. PMID:20147735

Kobayashi, Yasuhisa; Alam, Mohammad Ashraful; Horiguchi, Ryo; Shimizu, Akio; Nakamura, Masaru

2010-06-01

116

Les Brulures Chimiques Par Le Laurier Rose  

PubMed Central

Summary Le laurier rose ou Nerium oleander est un arbuste qui pousse naturellement dans les régions méditerranéennes. Au Maroc on le trouve dans les lieux humides. Il est réputé par ses risques de toxicité systémique en cas d'empoisonnement à cause de la présence de deux alcaloïdes, surtout l'oléandrine. La littérature illustre des cas d'utilisation locale des feuilles de cette plante contre la gale, les hémorroïdes et les furoncles. Nous rapportons deux cas de brûlures chimiques par le laurier rose de gravité différente. Cela doit aboutir à une information élargie de la population, ainsi qu'une réglementation stricte de sa commercialisation. PMID:21991211

Bakkali, H.; Ababou, M.; Nassim Sabah, T.; Moussaoui, A.; Ennouhi, A.; Fouadi, F.Z.; Siah, S.; Ihrai, H.

2010-01-01

117

Molecular characterization of the Salmonella typhimurium parE gene.  

PubMed Central

The DNA sequence of the wild type S. typhimurium parE gene was determined. The predicted protein has 96.7% amino acid identity with the ParE protein of E.coli, but is 29 amino acids longer, due to an additional basepair in the 3' end of the S. typhimurium gene. Subclones of the S. typhimurium parE gene localized the sites of four heat sensitive mutations within parE. The parE206 and parE374 mutations are identical (Val67-Met) and lie in a highly conserved region corresponding to the ATP binding pocket of GyrB. Two additional heat sensitive mutations were sequenced and predict the following amino acid substitutions: parE377 (Gly399-Ser) and parE493 (Thr583-Pro). All of the heat sensitive mutations lie in regions with strong amino acid homology to GyrB. PMID:8388096

Springer, A L; Schmid, M B

1993-01-01

118

A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition Assembly  

SciTech Connect

Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

B Chaudhuri; S Gupta; V Urban; M Chance; R DMello; L Smith; K Lyons; J Gee

2011-12-31

119

Kallikrein 6 Signals through PAR1 and PAR2 to Promote Neuron Injury and Exacerbate Glutamate Neurotoxicity  

PubMed Central

CNS trauma generates a proteolytic imbalance contributing to secondary injury, including axonopathy and neuron degeneration. Kallikrein 6 (Klk6) is a serine protease implicated in neurodegeneration and here we investigate the role of protease activated receptors 1 (PAR1) and PAR2 in mediating these effects. First we demonstrate Klk6 and the prototypical activator of PAR1, thrombin, as well as PAR1 and PAR2, are each elevated in murine experimental traumatic spinal cord injury (SCI) at acute or subacute time points. Recombinant Klk6 triggered ERK1/2 signaling in cerebellar granule neurons and in the NSC34 spinal cord motoneuron cell line, in a PI3K and MEK-dependent fashion. Importantly, lipopeptide inhibitors of PAR1 or PAR2, and PAR1 genetic deletion, each reduced Klk6-ERK1/2 activation. In addition, Klk6 and thrombin promoted degeneration of cerebellar neurons and exacerbated glutamate neurotoxicity. Moreover, genetic deletion of PAR1 blocked thrombin-mediated cerebellar neurotoxicity and reduced the neurotoxic effects of Klk6. Klk6 also increased glutamate-mediated Bim signaling, PARP cleavage and lactate dehydrogenase (LDH) release in NSC34 motoneurons and these effects were blocked by PAR1 and PAR2 lipopeptide inhibitors. Taken together these data point to a novel Klk6-signaling axis in CNS neurons that is mediated by PAR1 and PAR2 and is positioned to contribute to neurodegeneration. PMID:23647384

Yoon, Hyesook; Radulovic, Maja; Wu, Jianmin; Blaber, Sachiko I.; Blaber, Michael; Fehlings, Michael G.; Scarisbrick, Isobel A.

2014-01-01

120

A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition  

SciTech Connect

Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

Chaudhuri, Barnali [University of Buffalo, The State University of New York; Gupta, Sayan [Case Western Reserve University; Urban, Volker S [ORNL; Chance, Mark [Case Western Reserve University; D'Mello, Rhijuta [Case Western Reserve University; Smith, Lauren [University of Buffalo, The State University of New York; Lyons, Kelly [University of Buffalo, The State University of New York; Gee, Jessica [University of Buffalo, The State University of New York

2010-01-01

121

DTERMINATION DE LA DILATATION DU MERCURE; Par M. P. CHAPPUIS.  

E-print Network

12 D�TERMINATION DE LA DILATATION DU MERCURE; Par M. P. CHAPPUIS. Les déterminations l'aites par Regnault (1) de la dilatation du mercure par la méthode absolue présentent, comme l'a remarqué Broch (2 dilatation du mercure par la méthode relative du thermomètre à poids, qui exige, il est vrai, une connais

Paris-Sud XI, Université de

122

suPAR and Team Nephrology  

PubMed Central

Primary focal segmental glomerulosclerosis (FSGS) accounts for nearly 10 % of patients who require renal replacement therapy. Elevated circulating levels of soluble urokinase receptor (suPAR) have been identified as a biomarker to discriminate primary FSGS from other glomerulopathies. Subsequent reports have questioned the diagnostic utility of this test. In a study in BMC Medicine, Huang et al. demonstrate that urinary soluble urokinase receptor (suPAR) excretion assists in distinguishing primary FSGS from other glomerular diseases, and that high plasma suPAR concentrations are not directly linked to a decline in glomerular filtration rate (GFR). This observation suggests that further investigation of suPAR is warranted in patients with FSGS. It should be interpreted in light of a recent report that B7-1 is expressed in the podocytes of a subset of patients with FSGS, and that blocking this molecule may represent the first successful targeted intervention for this disease. These advances highlight the rapid pace of scientific progress in the field of nephrology. Nephrologists should work together, share resources, and expedite the design of protocols to evaluate these novel biomarkers in a comprehensive and scientifically valid manner. Please see related article http://www.biomedcentral.com/1741-7015/12/81. PMID:24885021

2014-01-01

123

REGISTRARIAT PAIEMENT PAR CARTE DE CRDIT  

E-print Network

disponible Date de naissance jj/mm/aaaa Prénom Nom de famille Adresse de courrier électronique ( ) Téléphone) Date Signature de l'étudiant(e) Date Faire parvenir au Registrariat : Par courrier électronique à

Skorobogatiy, Maksim

124

Intramural Sports Par 3 Golf League  

E-print Network

between June 16th and June 26th or online at http://oregonstate.edu/recsports/ Manager's Meeting of risks inherent in intramural participation. Rules Intramural Sports Par 3 Golf Rules will be used must be ready to tee off by 6pm. Office Use Only: _________DATE OF ENTRY _________STAFF INITIALS #12;

Escher, Christine

125

uPAR: a versatile signalling orchestrator  

Microsoft Academic Search

The plasminogen system has been implicated in clot lysis, wound healing, tissue regeneration, cancer and many other processes that affect health and disease. The urokinase receptor uPAR was originally thought to assist the directional invasion of migrating cells, but it is now becoming increasingly evident that this proteinase receptor elicits a plethora of cellular responses that include cellular adhesion, differentiation,

Francesco Blasi; Peter Carmeliet

2002-01-01

126

Par(-4)oxysm in Breast Cancer  

PubMed Central

Summary Women suffering from breast cancer often succumb to incurable recurrent disease resulting from therapy-resistant cancer cells. In this issue of Cancer Cell, Alvarez and colleagues identify downregulation of the tumor suppressor Par-4 as the key determinant in apoptosis evasion that leads to tumor recurrence in breast cancer. PMID:23845436

Shrestha-Bhattarai, Tripti; Hebbar, Nikhil; Rangnekar, Vivek M.

2013-01-01

127

Historic macrophyte development in Par Pond  

Microsoft Academic Search

Aerial photographs from 1975, 1980, and 1983 were examined to evaluate the changes that have occurred in the wetland vegetation of Par Pond, a reactor-cooling reservoir. Evaluation of the aerial photographs was based on comparisons with ground-level vegetation maps made during July 1984. Comparisons of photographs from August and December of 1983 revealed the main seasonal change in the aerial

1985-01-01

128

MESURE CINTIQUE DES TEMPRATURES par M. FOURNET,  

E-print Network

chaud par une membrane dont la rupture brusque libère un jet de particules, d'une part, et permet de. Abstract. 2014 The proposed method allows the measurement of high gas temperature in fast transient phenomena, such as those encountered in shock tubes used in aerodynamics, plasma stu- dies, etc

Boyer, Edmond

129

UNIVERSITE DE GRENOBLE attribu par la bibliothque  

E-print Network

as "Simultaneous Localization And Mapping" (SLAM) and finally (3) Detect And Track Moving Objects (DATMO of the environment to build a map of the environment and localize the vehicle inside this map : this task is know et Technologies de l'Information, Informatique" présentée et soutenue publiquement par Olivier AYCARD

Paris-Sud XI, Université de

130

Contrle de drones et robots par reconnaissance de mouvements complexes  

E-print Network

Contrôle de drones et robots par reconnaissance de mouvements complexes Anaïs Finzi, Bastien Tauran contexte du pilotage de drones et de robots par des mouvements de l'opérateur détectés par des applied to complex gesture recognition in the context of drones and robots control, when the human

Boyer, Edmond

131

INSTITUT NATIONAL POLYTECHNIQUE DE GRENOBLE N attribu par la bibliothque  

E-print Network

ou friction stir welding (FSW) 4 A-1 Principe du soudage par friction malaxage (friction stir welding septembre 2004 Titre : Genèse des microstructures lors du soudage par friction malaxage d'alliages d'aluminium MATIERES i INTRODUCTION 1 CHAPITRE I. Etude bibliographique 4 A. Procédé de soudage par friction malaxage

Paris-Sud XI, Université de

132

Ultrastructure of the pars intermedia of the adult sheep hypophysis  

Microsoft Academic Search

Light microscopy of coronal sections of the sheep pars intermedia revealed a compact, incompletely lobulated V-shaped region about 15–20 cells thick, situated between the pars distalis and the pars nervosa. A prominent hypophysial cleft and follicles containing a colloid-like substance were seen.

R. A. Perry; P. M. Robinson; G. B. Ryan

1981-01-01

133

Proposition de thse Contribution la modlisation physique du dosage par  

E-print Network

Proposition de thèse Contribution à la modélisation physique du dosage par microanalyse performante pour le dosage des matériaux comportant des actinides par microsonde électronique. Cette technique de références virtuels » obtenus par des calculs théoriques et des simulations de type Monte Carlo

Demouchy, Sylvie

134

INFLUENCE DE L'IMMUNIT PASSIVE TRANSMISE PAR LE COLOSTRUM  

E-print Network

INFLUENCE DE L'IMMUNIT� PASSIVE TRANSMISE PAR LE COLOSTRUM SUR L'�VOLUTION DE LA PESTE PORCINE transmise par le colostrum a permis de mettre en évidence chez r8 porcelets, de 20 à 25 kg, issus de truies transmise par le colostrum. Les applications qu'entraînent ces observations font l'objet de la discussion

Paris-Sud XI, Université de

135

TUDE DE UAs2 PAR DIFFRACTION DE NEUTRONS Par A. OLS,  

E-print Network

561. �TUDE DE UAs2 PAR DIFFRACTION DE NEUTRONS Par A. OL�S, Service de Physique du Solide et de neutrons du composé quadratique UAs2 a permis de préciser la structure cristalline et d'établir la UAs2 gives an improved crystal structure and establishes the magnetic structure below the Néel point

Paris-Sud XI, Université de

136

Localization of an endocannabinoid system in the hypophysial pars tuberalis and pars distalis of man  

Microsoft Academic Search

The hypophysial pars tuberalis (PT) acts as an important interface between neuroendocrine brain centers (hypothalamus, pineal\\u000a organ) and the pars distalis (PD) of the hypophysis. Recently, we have identified an endocannabinoid system in the PT of hamsters\\u000a and provided evidence that 2-arachidonoylglycerol is a messenger molecule that appears to play an essential role in seasonal\\u000a reproduction and prolactin release by

Shinobu Yasuo; Claudia Unfried; Mattias Kettner; Gerd Geisslinger; Horst-Werner Korf

2010-01-01

137

Similar requirements for CDC-42 and the PAR-3/PAR-6/PKC-3 complex in diverse cell types  

E-print Network

Similar requirements for CDC-42 and the PAR-3/PAR-6/PKC-3 complex in diverse cell types David P kinase C (aPKC) plays a central role in cell polarisation. The small G protein Cdc42 also functions, it is not yet known whether Cdc42 and the Par3 complex widely function together in development or whether

Ahringe, Julie

138

The Human Pseudoautosomal Region (PAR): Origin, Function and Future  

PubMed Central

The pseudoautosomal regions (PAR1 and PAR2) of the human X and Y chromosomes pair and recombine during meiosis. Thus genes in this region are not inherited in a strictly sex-linked fashion. PAR1 is located at the terminal region of the short arms and PAR2 at the tips of the long arms of these chromosomes. To date, 24 genes have been assigned to the PAR1 region. Half of these have a known function. In contrast, so far only 4 genes have been discovered in the PAR2 region. Deletion of the PAR1 region results in failure of pairing and male sterility. The gene SHOX (short stature homeobox-containing) resides in PAR1. SHOX haploinsufficiency contributes to certain features in Turner syndrome as well as the characteristics of Leri-Weill dyschondrosteosis. Only two of the human PAR1 genes have mouse homologues. These do not, however, reside in the mouse PAR1 region but are autosomal. The PAR regions seem to be relics of differential additions, losses, rearrangements and degradation of the X and Y chromosome in different mammalian lineages. Marsupials have three homologues of human PAR1 genes in their autosomes, although, in contrast to mouse, do not have a PAR region at all. The disappearance of PAR from other species seems likely and this region will only be rescued by the addition of genes to both X and Y, as has occurred already in lemmings. The present review summarizes the current understanding of the evolution of PAR and provides up-to-date information about individual genes residing in this region. PMID:18660847

Helena Mangs, A; Morris, Brian J

2007-01-01

139

LH serum levels during ovarian stimulation as predictors of ovarian response and assisted reproduction outcome in down-regulated women stimulated with recombinant FSH  

Microsoft Academic Search

BACKGROUND: There has been much debate about the effect of 'residual' LH levels in normogonadotrophic women undergoing assisted reproduction with GnRH agonist down-regulation and recombinant FSH ovarian stimulation. The aim of this prospective study, where receiver-operating characteristic (ROC) analysis was used, was to assess further the usefulness of serum LH levels as predictors of ovarian response, assisted reproduction treatment outcome,

Joana Penarrubia; Francisco Fabregues; Montserrat Creus; Dolors Manau; Roser Casamitjana; Marta Guimera ´; Francisco Carmona; Juan A. Vanrell; Juan Balasch

140

Insufficient androgen and FSH signaling may be responsible for the azoospermia of the infantile primate testes despite exposure to an adult-like hormonal milieu  

PubMed Central

BACKGROUND In humans, as well as in other higher primates, the infantile testis is exposed to an adult-like hormonal milieu, but spermatogenesis is not initiated at this stage of primate development. In the present study, we examined the molecular basis of this intriguing infertile state of the primate testis. METHODS The integrity of androgen receptor (AR) and FSH receptor (FSHR) signaling pathways in primary cultures of Sertoli cells (Scs) harvested from azoospermic infant and spermatogenic pubertal monkey testes were investigated under identical in vitro hormonal conditions. In order to synchronously harvest Scs from early pubertal testis, the activation of testicular puberty was timed experimentally by prematurely initiating gonadotrophin secretion in juvenile animals with an intermittent infusion of gonadotrophin-releasing hormone. RESULTS While qRT–PCR demonstrated that AR and FSHR mRNA expression in Scs from infant and pubertal testes were comparable, androgen-binding and FSH-mediated cAMP production by infant Scs was extremely low. Compromised AR and FSHR signaling in infant Scs was further supported by the finding that testosterone (T) and FSH failed to augment the expression of the T responsive gene, claudin 11, and the FSH responsive genes, inhibin-?B, stem cell factor (SCF) and glial cell line-derived neurotrophic factor (GDNF) in Scs harvested at this stage of development. CONCLUSION These results indicate that compromised AR and FSHR signaling pathways in Scs underlie the inability of the infant primate testis to respond to an endogenous hormonal milieu that later in development, at the time puberty, stimulates the initiation of spermatogenesis. This finding may have relevance to some forms of idiopathic infertility in men. PMID:22669085

Majumdar, Subeer S.; Sarda, Kanchan; Bhattacharya, Indrashis; Plant, Tony M.

2012-01-01

141

Regulation of FSH? induction in L?T2 cells by BMP2 and an Activin A/BMP2 chimera, AB215.  

PubMed

Activins and bone morphogenetic proteins (BMPs) share activin type 2 signaling receptors but utilize different type 1 receptors and Smads. We designed AB215, a potent BMP2-like Activin A/BMP2 chimera incorporating the high-affinity type 2 receptor-binding epitope of Activin A. In this study, we compare the signaling properties of AB215 and BMP2 in HEK293T cells and gonadotroph L?T2 cells in which Activin A and BMP2 synergistically induce FSH?. In HEK293T cells, AB215 is more potent than BMP2 and competitively blocks Activin A signaling, while BMP2 has a partial blocking activity. Activin A signaling is insensitive to BMP pathway antagonism in HEK293T cells but is strongly inhibited by constitutively active (CA) BMP type 1 receptors. By contrast, the potencies of AB215 and BMP2 are indistinguishable in L?T2 cells and although AB215 blocks Activin A signaling, BMP2 has no inhibitory effect. Unlike HEK293T, Activin A signaling is strongly inhibited by BMP pathway antagonism in L?T2 cells but is largely unaffected by CA BMP type 1 receptors. BMP2 increases phospho-Smad3 levels in L?T2 cells, in both the absence and the presence of Activin A treatment, and augments Activin A-induced FSH?. AB215 has the opposite effect and sharply decreases basal phospho-Smad3 levels and blocks Smad2 phosphorylation and FSH? induction resulting from Activin A treatment. These findings together demonstrate that while AB215 activates the BMP pathway, it has opposing effects to those of BMP2 on FSH? induction in L?T2 cells apparently due to its ability to block Activin A signaling. PMID:25100748

Jung, Jae Woo; Ahn, Chihoon; Shim, Sun Young; Gray, Peter C; Kwiatkowski, Witek; Choe, Senyon

2014-10-01

142

Effects of castration and androgen-treatment on the expression of FSH-beta and LH-beta in the three-spine stickleback, gasterosteus aculeatus--feedback differences mediating the photoperiodic maturation response?  

PubMed

In many animals, including the three-spine stickleback (Gasterosteus aculeatus), photoperiod strongly influences reproduction. The aim of this study was to investigate if feedback mechanisms on the brain-pituitary-gonadal axis play a role in mediating the photoperiodic response in the stickleback. To that end, stickleback males, exposed to either non-stimulatory short photoperiod (light/dark 8:16) or under stimulatory long photoperiod (LD 16:8), were subjected to either sham-operation, castration, castration combined with treatment with the androgens 11-ketoandrostenedione (11KA) and testosterone (T), and the effects on levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH)-beta mRNA were analyzed. During breeding season the kidney of the stickleback male hypertrophies and produces a glue used for building nests. Kidney weight and expression of both LH-beta and FSH-beta were higher in sham-operated fish kept under long than under short photoperiod. Under both photoperiods, LH-beta mRNA levels were lower in castrated males compared to sham-operated males and treatment with 11KA and T increased expression, indicating a positive feedback. A positive feedback was also found on FSH-beta expression under long photoperiod, where castration decreased, and androgen replacement restored FSH-beta mRNA expression. On the contrary, castration under short photoperiod instead increased FSH-beta levels whereas treatment with 11KA and T decreased FSH-beta expression, indicating a negative feedback on FSH-beta under these conditions. The positive feedback on FSH-beta expression under stimulatory photoperiod may accelerate maturation, whereas the negative feedback under inhibitory photoperiod may suppress maturation. This could be part of the mechanisms by which photoperiod controls maturation. PMID:18664367

Hellqvist, Anna; Schmitz, Monika; Borg, Bertil

2008-09-01

143

Par Pond refill water quality sampling  

SciTech Connect

This study was designed to document anoxia and its cause in the event that the anoxia caused a fish kill. However, no fish kill was observed during this study, and dissolved oxygen and nutrient concentrations generally remained within the range expected for southeastern reservoirs. Par Pond water quality monitoring will continue during the second summer after refill as the aquatic macrophytes become reestablished and nutrients in the sediments are released to the water column.

Koch, J.W. II; Martin, F.D.; Westbury, H.M.

1996-08-01

144

Par-4 prevents breast cancer recurrence  

PubMed Central

Therapy resistance and disease recurrence are two of the most challenging aspects in breast cancer treatment. A recent article in Cancer Cell makes a significant contribution toward a better understanding of this therapeutic problem by establishing downregulation of the tumor suppressor Par-4 as the primary determinant of breast cancer recurrence. This viewpoint brings forth the importance of their findings and its implications on future research and therapy. PMID:24164776

2013-01-01

145

Effect of addition of FSH, LH and proteasome inhibitor MG132 to in vitro maturation medium on the developmental competence of yak (Bos grunniens) oocytes  

PubMed Central

Background The competence for embryonic development after IVF is low in the yak, therefore, we investigated the effects of supplementation of FSH, LH and the proteasome inhibitor MG132 in IVM media on yak oocyte competence for development after IVF. Methods In Experiment 1, yak cumulus-oocyte complexes (COCs) were in vitro matured (IVM) in TCM-199 with 20% fetal calf serum (FCS), 1 microg/mL estradiol-17beta, and different combinations of LH (50 or 100 IU/mL) and FSH (0, 1, 5, 10 microg/mL) at 38.6 degrees C, 5% CO2 in air for 24 h. Matured oocytes were exposed to frozen–thawed, heparin-capacitated yak sperm. Presumptive zygotes were cultured in SOF medium containing 6 mg/ml BSA, 0.5 mg/mL myoinositol, 3% (v/v) essential amino acids, 1% nonessential amino acids and 100 ?g/mL L-glutamine (48 h, 38.5 degrees C, 5% CO2, 5% O2, and 90% N2). In Experiment 2, cumulus cells were collected at the end of IVM to determine FSHR and LHR mRNA expression by real-time PCR. In Experiment 3 and 4, COCs were cultured in the presence or absence of the proteasomal inhibitor MG132 from either 0–6 h or 18–24 h after initiation of maturation. Results The optimum concentration of FSH and LH in IVM media was 5 microg/mL FSH and 50 IU/mL LH which resulted in the greatest cleavage (79.1%) and blastocyst rates (16.1%). Both FSHR and LHR mRNA were detected in yak cumulus cells after IVM. Treatment with MG132 early in maturation reduced (P?FSH and LH in IVM medium, and treatment with MG132 late in maturation can improve yak oocytes competence for development after IVF. PMID:24754924

2014-01-01

146

A Conserved Mode of Protein Recognition and Binding in a ParD?ParE Toxin?Antitoxin Complex  

SciTech Connect

Toxin-antitoxin (TA) systems form a ubiquitous class of prokaryotic proteins with functional roles in plasmid inheritance, environmental stress response, and cell development. ParDE family TA systems are broadly conserved on plasmids and bacterial chromosomes and have been well characterized as genetic elements that promote stable plasmid inheritance. We present a crystal structure of a chromosomally encoded ParD-ParE complex from Caulobacter crescentus at 2.6 {angstrom} resolution. This TA system forms an {alpha}{sub 2}{beta}{sub 2} heterotetramer in the crystal and in solution. The toxin-antitoxin binding interface reveals extensive polar and hydrophobic contacts of ParD antitoxin helices with a conserved recognition and binding groove on the ParE toxin. A cross-species comparison of this complex structure with related toxin structures identified an antitoxin recognition and binding subdomain that is conserved between distantly related members of the RelE/ParE toxin superfamily despite a low level of overall primary sequence identity. We further demonstrate that ParD antitoxin is dimeric, stably folded, and largely helical when not bound to ParE toxin. Thus, the paradigmatic model in which antitoxin undergoes a disorder-to-order transition upon toxin binding does not apply to this chromosomal ParD-ParE TA system.

Dalton, Kevin M.; Crosson, Sean (UC)

2010-05-06

147

A conserved mode of protein recognition and binding in a ParD-ParE toxin-antitoxin complex†  

PubMed Central

Toxin-antitoxin (TA) systems form a ubiquitous class of prokaryotic proteins with functional roles in plasmid inheritance, environmental stress response, and cell development. ParDE-family TA systems are broadly conserved on plasmids and bacterial chromosomes, and have been well characterized as genetic elements that promote stable plasmid inheritance. We present a crystal structure of a chromosomally-encoded ParD-ParE complex from Caulobacter crescentus at 2.6 Å resolution. This TA system forms an ?2?2 heterotetramer in the crystal and in solution. The toxin-antitoxin binding interface reveals extensive polar and hydrophobic contacts of ParD antitoxin helices with a conserved recognition and binding groove on the ParE toxin. A cross-species comparison of this complex structure with related toxin structures identified an antitoxin recognition and binding sub-domain that is conserved between distantly-related members of the RelE/ParE toxin superfamily despite low overall primary sequence identity. We further demonstrate that ParD antitoxin is dimeric, stably folded, and largely helical when not bound to ParE toxin. Thus, the paradigmatic model in which antitoxin undergoes a disorder-to-order transition upon toxin binding does not apply to this chromosomal ParD-ParE TA system. PMID:20143871

Dalton, Kevin M.; Crosson, Sean

2010-01-01

148

Apoptosis and Tumor Resistance Conferred by Par-4  

PubMed Central

Par-4 is a tumor suppressor protein with a pro-apoptotic function. Epigenetic silencing of Par-4 is seen in diverse tumors, and Par-4 knockout mice develop spontaneous tumors in various tissues. Endogenous Par-4 is essential for sensitization of cells to diverse apoptotic stimuli, whereas ectopic expression of Par-4 can selectively induce apoptosis in cancer cells. The cancer-specific pro-apoptotic action of Par-4 resides in its centrally located SAC domain. This chapter reviews a novel mouse model with ubiquitous expression of the SAC domain. These SAC transgenic mice display normal development and life span, and, most importantly, are resistant to spontaneous, as well as oncogene-induced, autochthonous tumors. The tumor resistant phenotype and undetectable toxicity of SAC in vivo suggests the SAC domain possesses tremendous therapeutic potential. PMID:18836307

Zhao, Yanming; Rangnekar, Vivek M.

2009-01-01

149

PAR2 Regulates Dental Pulp Inflammation Associated with Caries  

Microsoft Academic Search

Protease-activated receptors (PARs) are G-protein-coupled receptors that are activated enzymatically by proteolysis of an N-terminal domain. The cleavage and activation of PARs by serine proteases represent a novel mechanism by which such enzymes could influence the host inflammatory response. The aim of this study was to determine whether PAR-2 expression and activation were increased in dental caries. Using immunohistochemistry, we

F. T. Lundy; T. M. Curtis; M. K. McGahon; G. J. Linden; C. R. Irwin; I. A. El Karim

2010-01-01

150

A new model for estimating boreal forest fPAR  

NASA Astrophysics Data System (ADS)

Life on Earth is continuously sustained by the extraterrestrial flux of photosynthetically active radiation (PAR, 400-700 nm) from the sun. This flux is converted to biomass by chloroplasts in green vegetation. Thus, the fraction of absorbed PAR (fPAR) is a key parameter used in carbon balance studies, and is listed as one of the Essential Climate Variables (ECV). Temporal courses of fPAR for boreal forests are difficult to measure, because of the complex 3D structures. Thus, they are most often estimated based on models which quantify the dependency of absorbed radiation on canopy structure. In this study, we adapted a physically-based canopy radiation model into a fPAR model, and compared modeled and measured fPAR in structurally different boreal forest stands. The model is based on the spectral invariants theory, and uses leaf area index (LAI), canopy gap fractions and spectra of foliage and understory as input data. The model differs from previously developed more detailed fPAR models in that the complex 3D structure of coniferous forests is described using an aggregated canopy parameter - photon recollision probability p. The strength of the model is that all model inputs are measurable or available through other simple models. First, the model was validated with measurements of instantaneous fPAR obtained with the TRAC instrument in nine Scots pine, Norway spruce and Silver birch stands in a boreal forest in southern Finland. Good agreement was found between modeled and measured fPAR. Next, we applied the model to predict temporal courses of fPAR using data on incoming radiation from a nearby flux tower and sky irradiance models. Application of the model to simulate diurnal and seasonal values of fPAR indicated that the ratio of direct-to-total incident radiation and leaf area index are the key factors behind the magnitude and variation of stand-level fPAR values.

Majasalmi, Titta; Rautiainen, Miina; Stenberg, Pauline

2014-05-01

151

A new method for PAR reduction in baseband DMT systems  

Microsoft Academic Search

The high peak-to-average power ratio (PAR) in real-baseband discrete multitone modulation (DMT) systems can significantly limit performance. Tone reservation techniques use unavailable or reserved tones to design a peak-cancelling signal that lowers the PAR of a transmit data block. Previous methods converge very slowly to a good solution. Our new active-set method converges much faster toward a minimum-PAR solution at

Brian S. Krongold; Douglas L. Jones

2001-01-01

152

2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) BARRACKS WITH RADAR ATTACHED. - Nike Hercules Missile Battery Summit Site, Battery Control Administration & Barracks Building, Anchorage, Anchorage, AK

153

Programmation Concurrent par Contraintes pour Vérifier un Protocole de Sécurité.  

E-print Network

??La Programmation Concurrente par Contraintes (CCP) est un modèle mathématique pour la spécification de systèmes concurrents où les agents (processus) ajoutent de l'information ou interrogent… (more)

Olarte, Carlos

2009-01-01

154

Cloning and Nucleotide Sequences of the Topoisomerase IV parC and parE Genes of Mycoplasma hominis  

PubMed Central

The topoisomerase IV parC and parE genes from the wall-less organism Mycoplasma hominis PG21 were cloned and sequenced. The coupled genes are located far from the DNA gyrase genes gyrA and gyrB. They encode proteins of 639 and 866 amino acids, respectively. As expected, the encoded ParE and ParC proteins exhibit higher homologies with the topoisomerase IV subunits of the gram-positive bacteria Staphylococcus aureus and Streptococcus pneumoniae than with their Escherichia coli counterparts. The conserved regions include the Tyr residue of the active site and the region involved in quinolone resistance (quinolone resistance-determining region [QRDR]) in ParC and the ATP-binding site and the QRDR in ParE. PMID:9687401

Bebear, Cecile M.; Charron, Alain; Bove, Joseph Marie; Bebear, Christiane; Renaudin, Joel

1998-01-01

155

Domain 1 of the urokinase receptor (uPAR) is required for uPAR-mediated cell binding to vitronectin  

Microsoft Academic Search

In the present paper we have analyzed uPAR-mediated cellular binding to vitronectin using the murine erythroid progenitor cell line 32D. We show that expression of uPAR in 32D cells promotes cellular binding to vitronectin, but fails to support cell spreading. The strength of binding is correlated to the expression level of uPAR and is strongly stimulated by the presence of

Nicolai Sidenius; Francesco Blasi

2000-01-01

156

The effect of PCB126, 77, and 153 on the intracellular mobilization of Ca+2 in bovine granulosa and luteal cells after FSH and LH surge in vitro.  

PubMed

Polychlorinated biphenyls (PCBs) are a group of persistent environmental pollutants that impair cattle reproduction. Among other effects, PCBs can disturb the intracellular mobilization of Ca(+2) in several cell types. Hence, it is possible that they disrupt the transduction of intracellular signals generated from gonadotropin (FSH/LH) receptors. In steroidogenic ovarian cells, a defect in Ca(+2) mobilization may have a detrimental influence on two important processes: the secretion of steroids (E2 or/and P4) and their morphological and functional differentiation. The aim of this study was to determine the influence of PCBs: 126 (dioxin-like) 77 (ambivalent) and 153 (estrogen-like) and a mixture of PCBs (Aroclor 1248) on these processes. Bovine granulosa and luteal cells were incubated for 72 hrs with PCBs (100 ng/ml), followed by Fura 2AM dye, and the fluctuations in intracellular Ca(+2) mobilization after FSH/LH treatment were determined using an inverted microscope coupled with a CCD camera. The intensity and area of fluorescence excited by UV light were detected in the green spectrum of visible light. Aroclor 1248 and PCBs 153 and 77 significantly decreased (P < 0.01-0.001) the effect of FSH on intracellular Ca(+2) mobilization in granulosa cells. In luteal cells, the most effective PCB on this process was PCB 77. The results revealed adverse effects of PCBs on the mobilization of intracellular Ca(+2). Moreover, the estrogen-like congeners were found to more effectively disturb this process than the dioxin-like PCB 126. Hence, it is possible for PCBs to have a negative influence on reproductive processes by affecting calcium mobilization. PMID:24195274

Mlynarczuk, J; Kowalik, M

2013-01-01

157

The response of the immature rat ovary to gonadotrophins: acute changes in cyclic AMP, progesteron, testosteron, androstenedione and oestradiol after treatment with PMS or FSH + LH.  

PubMed

Radioimmunoassays were used to measure changes in progesterone, testosterone, androstenedione, oestradiol, gonadotrophin and ovarian cyclic AMP in immature female rats during the first 24 h after exposure to slowly (PMS) or rapidly (FSH + LH) disappearing gonadotrophins. Cyclic AMP was increased 30 min after injection of either kind of gonadotrophin but it had returned to control level within 4 h. Serum and ovarian testosterone and androstenedione also increased to a peak at 30 min but decreased to base line by the 4th h. Multiple injections of FSH + LH maintained an elevated serum testosterone level but they had little effect upon the secretion of androstenedione. Serum and ovarian progesterone increased quickly after treatment with gonadotrophin. With PMS the peak in the serum was reached at 8 h, it remained high for 4 h and then fell precipitously between the 12th and 16th h. FSH + LH produced a prompt increase in serum progesterone but the level could be maintained only by repeated doses given every 4 h. Oestradiol was not increased in the serum or the ovot produce an increase in oestrogen but a transient increase was found with 3 doses; 4 doses kept an elevated level of oestradiol for 12 h. These results indicate that the aromatizing system of the immature rat ovary is relatively inactive and that continual stimulation by gonadotrophin for about 10-12 h is necessary to bring about increased function. In contrast, the mechanisms for the synthesis and secretion of progesterone and androgens are vary active and can be immediately stimulated by exposure to gonadotrophins. PMID:179259

Sashida, T; Johnson, D C

1976-06-01

158

Ontogeny of immunoreactive Lh and Fsh cells in relation to early ovarian differentiation and development in protogynous hermaphroditic ricefield eel Monopterus albus.  

PubMed

Luteinizing hormone (Lh) and follicle-stimulating hormone (Fsh) control many aspects of gonadal development and function in teleosts. In the present paper, the specific antisera against ricefield eel Lhb (Lh beta subunit), Fshb (Fsh beta subunit), and Cga (the common pituitary glycoprotein hormone alpha subunit) were generated, and the cellular localization, initial appearance, and subsequent development of gonadotrophs in relation to early ovarian differentiation and development in the ricefield eel, a protogynous sex-changing teleost, were examined with immunochemistry. Lhb- and Fshb-immunoreactive signals were identified in distinct pituitary cells that occupied primarily the peripheral regions of the adenohypophysis. During ontogeny, Lhb-immunoreactive signals were first detected in the pituitary around 40 days after hatching (dah) when the oogonia transitioned into early primary growth oocytes, and the intensity of immunoreactivity increased concomitantly with the growth of primary oocytes from 60 to 140 dah. During overwintering from 170 to 230 dah, Lhb-immunoreactive signals were significantly decreased when a large proportion of perinucleolus oocytes contained intense Balbiani bodies. In contrast, Fshb-immunoreactive signals were not detectable in the pituitary until around 230 dah (in the spring after hatching) and slightly increased from 285 dah when the late perinucleolus oocytes began to enter the secondary growth phase. Both Lhb- and Fshb-immunoreactive cells were increased when the early cortical alveoli oocytes emerged at 300 dah. The mRNA expression of lhb and fshb coincided with their immunoreactive signals. Taken together, these results suggest that only Lh is involved in primary oocyte growth in ricefield eels, but both Fsh and Lh are important for the secondary ooctye growth. PMID:22174021

Wu, Yangsheng; He, Zhi; Zhang, Lihong; Jiang, He; Zhang, Weimin

2012-03-01

159

Diet-induced obesity, adipose inflammation, and metabolic dysfunction correlating with PAR2 expression are attenuated by PAR2 antagonism.  

PubMed

Excessive uptake of fatty acids and glucose by adipose tissue triggers adipocyte dysfunction and infiltration of immune cells. Altered metabolic homeostasis in adipose tissue promotes insulin resistance, type 2 diabetes, hypertension, and cardiovascular disease. Inflammatory and metabolic processes are mediated by certain proteolytic enzymes that share a common cellular target, protease-activated receptor 2 (PAR2). This study showed that human and rat obesity correlated in vivo with increased expression of PAR2 in adipose tissue, primarily in stromal vascular cells (SVCs) including macrophages. PAR2 was expressed more than other PARs on human macrophages and was increased by dietary fatty acids (palmitic, stearic, and myristic). A novel PAR2 antagonist, GB88 (5-isoxazoyl-Cha-Ile-spiroindene-1,4-piperidine), given orally at 10 mg/kg/d (wk 8-16) reduced body weight by ?10% in obese rats fed a high-carbohydrate high-fat (HCHF) diet for 16 wk, and strongly attenuated adiposity, adipose tissue inflammation, infiltrated macrophages and mast cells, insulin resistance, and cardiac fibrosis and remodeling; while reversing liver and pancreatic dysfunction and normalizing secretion of PAR2-directed glucose-stimulated insulin secretion in MIN6 ? cells. In summary, PAR2 is a new biomarker for obesity, and its expression is stimulated by dietary fatty acids; PAR2 is a substantial contributor to inflammatory and metabolic dysfunction; and a PAR2 antagonist inhibits diet-induced obesity and inflammatory, metabolic, and cardiovascular dysfunction. PMID:23964081

Lim, Junxian; Iyer, Abishek; Liu, Ligong; Suen, Jacky Y; Lohman, Rink-Jan; Seow, Vernon; Yau, Mei-Kwan; Brown, Lindsay; Fairlie, David P

2013-12-01

160

A critical role of follicle-stimulating hormone (Fsh) in mediating the effect of clotrimazole on testicular steroidogenesis in adult zebrafish.  

PubMed

Clotrimazole is a pharmaceutical fungicide known to inhibit several cytochrome P450 enzyme activities, including several steroidogenic enzymes. This study aimed to assess short-term in vivo effects of clotrimazole exposure on blood 11-ketotestosterone (11-KT) levels and on the transcriptional activity of genes in pituitary and testis tissue that are functionally relevant for androgen production with the view to further characterize the mode of action of clotrimazole on the hypothalamus-pituitary-gonad axis in zebrafish, a model vertebrate in toxicology. Adult male zebrafish were exposed to measured concentrations in water of 71, 159 and 258?g/L of clotrimazole for 7 days. Expression of pituitary gonadotropins ? subunit (lhb, fshb), testicular gonadotropins receptors (lhcgr, fshr) and testicular steroidogenesis-related genes (e.g., star, cyp17a1, cyp11c1) were assessed. Blood concentrations of 11-KT were measured. Short-term exposure to clotrimazole induced a concentration-dependent increase of star, cyp17a1, and cyp11c1 gene expression and Cyp17a1 and Cy11c1 protein synthesis in Leydig cells, but androgen levels in blood remained unchanged. fshb, but not lhb mRNA levels in the pituitary tended to increase in clotrimazole-exposed zebrafish. Testicular expression of the Fsh receptor gene was significantly up-regulated following exposure, when expression of this receptor was significantly correlated to the expression of steroidogenesis-related genes. Moreover, the Fsh-regulated insulin-like growth factor 3 (igf3) gene, a fish-specific Igf peptide expressed in Sertoli cells, was induced in testes. By using a network of genes functioning in pituitary and testis tissue, our study demonstrated that clotrimazole induced a cascade of molecular and cellular events which are in agreement with a role for Fsh (1) in stimulating Leydig cell steroidogenesis to compensate the inhibitory action of clotrimazole on 11-KT synthesis and (2) in inducing the expression of Fsh-regulated igf3 in Sertoli cells. PMID:22564764

Baudiffier, Damien; Hinfray, Nathalie; Vosges, Mélanie; Creusot, Nicolas; Chadili, Edith; Porcher, Jean-Marc; Schulz, Rüdiger W; Brion, François

2012-08-16

161

Gdnf-gfra1 pathway is expressed in a spermatogenetic-dependent manner and is regulated by fsh in a fish testis.  

PubMed

What makes the spermatogonial stem cells (SSCs) self-renew or differentiate to produce spermatozoa is barely understood, in particular in nonmammalian species. Our research explores possible regulations of the SSC niche in teleost, locally by paracrine factors and peripherally by hormonal regulation. In the present study, we focus on the Gdnf-Gfra1 pathway that plays a major role in the regulation of SSC self-renewal in mammals. We describe a complex evolution of the genes encoding for Gdnf and Gfra1 proteins in trout with the emergence of three gdnf and two gfra1 paralogs. Using quantitative PCR measurements in isolated testicular cell populations, the gdnfb paralog was found expressed in A-spermatogonia and probably in another testicular cell type. In contrast, the transcript of gfra1a, the Gdnf receptor, was preferentially expressed in a population of undifferentiated A-spermatogonia (und A-Spg) separated by centrifugal elutriation. These und A-Spg also demonstrated high stemness potential in transplantation studies and preferentially expressed nanos2, a putative SSC marker in trout (Bellaiche et al., Biol Reprod 2014; 90:79). Flow cytometer experiments demonstrate that only a subfraction of und A-Spg express Gfra1. In trout, spermatogenesis develops along a strict annual cycle, and gdnfb and its receptor were expressed in a spermatogenetic activity-dependent manner. In particular, a dramatic increase of the gdnfb transcript coincided with the progressive cessation of rapid spermatogonial proliferation and of meiosis toward the end of the reproductive cycle. Together these results suggest that, in trout, Gdnfb is involved in the repression of und A-Spg differentiation. Fsh is an endocrine regulator of SSCs self-renewal through the up-regulation of Gdnf in rodents. We demonstrate that in trout, in vitro Fsh treatment stimulated the expression of the gfra1a1 but not of its ligand, gdnfb. Fsh treatment also stimulated the proliferation of und A-Spg cocultured with testicular somatic cells. Based on those results, the Gfra1-positive cells could correspond to the putative SSCs in rainbow trout, and we propose that the balance between SSC self-renewal and differentiation during the trout spermatogenetic cycle is under paracrine regulation by Gdnfb, which represses, and under peripheral regulation by Fsh via the control of gfra1a1 expression. PMID:25165121

Bellaïche, Johanna; Goupil, Anne-Sophie; Sambroni, Elisabeth; Lareyre, Jean-Jacques; Le Gac, Florence

2014-10-01

162

Genetic Polymorphisms Influence the Ovarian Response to rFSH Stimulation in Patients Undergoing In Vitro Fertilization Programs with ICSI  

PubMed Central

Introduction Obtaining an adequate number of high-quality oocytes is a major challenge in controlled ovarian hyperstimulation (COH). To date, a range of hormonal and clinical parameters have been used to optimize COH but none have significant predictive value. This variability could be due to the genetic predispositions of single-nucleotide polymorphisms (SNPs). Here, we assessed the individual and combined impacts of thirteen SNPs that reportedly influence the outcome of in vitro fertilisation (IVF) on the ovarian response to rFSH stimulation for patients undergoing intracytoplasmic sperm injection program (ICSI). Results Univariate analysis revealed that only FSHR, ESR2 and p53 SNPs influenced the number of mature oocytes. The association was statistically significant for FSHR (p=0.0047) and ESR2 (0.0017) in the overall study population and for FSHR (p=0.0009) and p53 (p=0.0048) in subgroup that was more homogeneous in terms of clinical variables. After Bonferroni correction and a multivariate analysis, only the differences for FSHR and ESR2 polymorphisms were still statistically significant. In a multilocus analysis, only the FSHR and AMH SNP combination significantly influenced oocyte numbers in both population (p<0.01). Discussion We confirmed the impact of FSHR and ESR2 polymorphisms on the IVF outcome. Furthermore, we showed for the first time that a p53 polymorphism (which is already known to impact embryo implantation) could influence the ovarian response. However, given that this result lost its statistical significance after multivariate analysis, more data are needed to draw firm conclusions. Only the FSHR and AMH polymorphism combination appears to influence mature oocyte numbers but this finding also needs to be confirmed. Materials and Methods A 13 gene polymorphisms: FSHR(Asn680Ser), p53(Arg72Pro), AMH(Ile49Ser), ESR2(+1730G>A), ESR1(?397T>C), BMP15(?9C>G), MTHFR1(677C>T), MTHFR2(1298A>C), HLA-G(?725C>G), VEGF(+405G>C), TNF?(?308A>G), AMHR(?482 A>G), PAI-1 (4 G/5 G), multiplex PCR assay was designed to genotype women undergoing ICSI program. We analyzed the overall study population (n=427) and a subgroup with homogeneous characteristics (n=112). PMID:22701696

Boudjenah, Radia; Molina-Gomes, Denise; Torre, Antoine; Bergere, Marianne; Bailly, Marc; Boitrelle, Florence; Taieb, Stephane; Wainer, Robert; Benahmed, Mohamed; de Mazancourt, Philippe; Selva, Jacqueline; Vialard, Francois

2012-01-01

163

Historic macrophyte development in Par Pond  

SciTech Connect

Aerial photographs from 1975, 1980, and 1983 were examined to evaluate the changes that have occurred in the wetland vegetation of Par Pond, a reactor-cooling reservoir. Evaluation of the aerial photographs was based on comparisons with ground-level vegetation maps made during July 1984. Comparisons of photographs from August and December of 1983 revealed the main seasonal change in the aerial coverage of wetland vegetation to be the wintertime loss of non-persistent emergent species such as Nelumbo lutea and Nymphaea odorata. Comparisons between September 1980 and August 1983 revealed that the lakeward extent of non-persistent macrophytes has increased by an average of 8.2 m, though not all sites have changed equally. For persistent macrophytes (principally Typha), the average increase in lakeward extent between December 1975 and August 1983 was 3.48 m. The extensive development of wetland vegetation in Par Pond as well as the substantial spread of vegetation over only a few years time indicates the high suitability of this habitat for the growth of wetland plants.

Grace, J.B.

1985-08-01

164

The tail of the ParG DNA segregation protein remodels ParF polymers and enhances ATP hydrolysis via an arginine finger-like motif  

PubMed Central

The ParF protein of plasmid TP228 belongs to the ubiquitous superfamily of ParA ATPases that drive DNA segregation in bacteria. ATP-bound ParF polymerizes into multistranded filaments. The partner protein ParG is dimeric, consisting of C-termini that interweave into a ribbon–helix–helix domain contacting the centromeric DNA and unstructured N-termini. ParG stimulates ATP hydrolysis by ParF ?30-fold. Here, we establish that the mobile tails of ParG are crucial for this enhancement and that arginine R19 within the tail is absolutely required for activation of ParF nucleotide hydrolysis. R19 is part of an arginine finger-like loop in ParG that is predicted to intercalate into the ParF nucleotide-binding pocket thereby promoting ATP hydrolysis. Significantly, mutations of R19 abrogated DNA segregation in vivo, proving that intracellular stimulation of ATP hydrolysis by ParG is a key regulatory process for partitioning. Furthermore, ParG bundles ParF-ATP filaments as well as promoting nucleotide-independent polymerization. The N-terminal flexible tail is required for both activities, because N-terminal ?ParG polypeptides are defective in both functions. Strikingly, the critical arginine finger-like residue R19 is dispensable for ParG-mediated remodeling of ParF polymers, revealing that the ParG N-terminal tail possesses two separable activities in the interplay with ParF: a catalytic function during ATP hydrolysis and a mechanical role in modulation of polymerization. We speculate that activation of nucleotide hydrolysis via an arginine finger loop may be a conserved, regulatory mechanism of ParA family members and their partner proteins, including ParA-ParB and Soj-Spo0J that mediate DNA segregation and MinD-MinE that determine septum localization. PMID:17261809

Barilla, Daniela; Carmelo, Emma; Hayes, Finbarr

2007-01-01

165

The tail of the ParG DNA segregation protein remodels ParF polymers and enhances ATP hydrolysis via an arginine finger-like motif.  

PubMed

The ParF protein of plasmid TP228 belongs to the ubiquitous superfamily of ParA ATPases that drive DNA segregation in bacteria. ATP-bound ParF polymerizes into multistranded filaments. The partner protein ParG is dimeric, consisting of C-termini that interweave into a ribbon-helix-helix domain contacting the centromeric DNA and unstructured N-termini. ParG stimulates ATP hydrolysis by ParF approximately 30-fold. Here, we establish that the mobile tails of ParG are crucial for this enhancement and that arginine R19 within the tail is absolutely required for activation of ParF nucleotide hydrolysis. R19 is part of an arginine finger-like loop in ParG that is predicted to intercalate into the ParF nucleotide-binding pocket thereby promoting ATP hydrolysis. Significantly, mutations of R19 abrogated DNA segregation in vivo, proving that intracellular stimulation of ATP hydrolysis by ParG is a key regulatory process for partitioning. Furthermore, ParG bundles ParF-ATP filaments as well as promoting nucleotide-independent polymerization. The N-terminal flexible tail is required for both activities, because N-terminal DeltaParG polypeptides are defective in both functions. Strikingly, the critical arginine finger-like residue R19 is dispensable for ParG-mediated remodeling of ParF polymers, revealing that the ParG N-terminal tail possesses two separable activities in the interplay with ParF: a catalytic function during ATP hydrolysis and a mechanical role in modulation of polymerization. We speculate that activation of nucleotide hydrolysis via an arginine finger loop may be a conserved, regulatory mechanism of ParA family members and their partner proteins, including ParA-ParB and Soj-Spo0J that mediate DNA segregation and MinD-MinE that determine septum localization. PMID:17261809

Barillà, Daniela; Carmelo, Emma; Hayes, Finbarr

2007-02-01

166

BINDING TO PKC-3, BUT NOT TO PAR-3 OR TO A CONVENTIONAL PDZ DOMAIN LIGAND, IS REQUIRED FOR PAR-6 FUNCTION IN C. ELEGANS  

PubMed Central

PAR-6 is a conserved protein important for establishment and maintenance of cell polarity in a variety of metazoans. PAR-6 proteins function together with PAR-3, aPKC and CDC-42. Mechanistic details of their interactions, however, are not fully understood. We studied the biochemical interactions between C. elegans PAR-6 and its binding partners and tested the requirements of these interactions in living worms. We show that PB1 domain-mediated binding of PAR-6 to PKC-3 is necessary for polarity establishment and PAR-6 cortical localization in C. elegans embryos. We also show that binding of PAR-6 and PAR-3 is mediated in vitro by a novel type of PDZ-PDZ interaction; the ?C strand of PAR-6 PDZ binds the ?D strand of PAR-3 PDZ1. However, this interaction is dispensable in vivo for PAR-6 function throughout the life of C. elegans. Mutations that specifically abolish conventional ligand binding to the PAR-6 PDZ domain also failed to affect PAR-6 function in vivo. We conclude that PAR-6 binding to PKC-3, but not to PAR-3 nor to a conventional PDZ ligand, is required for PAR-6 cortical localization and function in C. elegans. PMID:20122916

Li, Jin; Kim, Heon; Aceto, Donato G.; Hung, Jeffrey; Aono, Shinya; Kemphues, Kenneth J.

2010-01-01

167

Concerning the dynamic instability of actin homolog ParM  

SciTech Connect

Using in vitro TIRF- and electron-microscopy, we reinvestigated the dynamics of native ParM, a prokaryotic DNA segregation protein and actin homolog. In contrast to a previous study, which used a cysteine ParM mutant, we find that the polymerization process of wild type ATP-ParM filaments consists of a polymerization phase and a subsequent steady state phase, which is dynamically unstable, like that of microtubules. We find that the apparent bidirectional polymerization of ParM, is not due to the intrinsic nature of this filament, but results from ParM forming randomly oriented bundles in the presence of crowding agents. Our results imply, that in the bacterium, ParM filaments spontaneously form bipolar bundles. Due to their intrinsic dynamic instability, ParM bundles can efficiently 'search' the cytoplasmic lumen for DNA, bind it equally well at the bipolar ends and segregate it approximately symmetrically, by the insertion of ParM subunits at either end.

Popp, David [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, Kouto, Sayo, Hyogo 679-5148 (Japan)]. E-mail: dpopp@spring8.or.jp; Yamamoto, Akihiro [RIKEN Harima Institute at Spring 8, Laboratory for Structural Biochemistry, Kouto, Sayo, Hyogo 679-5148 (Japan); Iwasa, Mitsusada [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, Kouto, Sayo, Hyogo 679-5148 (Japan); Narita, Akihiro [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, Kouto, Sayo, Hyogo 679-5148 (Japan); Maeda, Kayo [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, Kouto, Sayo, Hyogo 679-5148 (Japan); Maeda, Yuichiro [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, Kouto, Sayo, Hyogo 679-5148 (Japan); RIKEN Harima Institute at Spring 8, Laboratory for Structural Biochemistry, Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University, Graduate School of Science, Division of Biological Science, Chikusa-ku, Nagoya 464-8602 (Japan)

2007-02-02

168

Par Pond vegetation status summer 1995 - July survey descriptive summary  

Microsoft Academic Search

A survey of the emergent shoreline aquatic plant, communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet (61 meters) above mean sea level, and continued with this July survey. Aquatic plant communities, similar to the pre-drawdown Par Pond communities, are becoming reestablished. Beds of maidencane (Panicum hemitomon), lotus (Nelumbo lutea), water lily

H. E. Jr. Mackey; R. S. Riley

1995-01-01

169

NOUVELLES MACHINES PNEUMATIQUES A MERCURE (1) ; Par M. FORTUNATO FLORIO.  

E-print Network

38 NOUVELLES MACHINES PNEUMATIQUES A MERCURE (1) ; Par M. FORTUNATO FLORIO. Je viens d'expérimenter de nouvelles machines pneumatiques (2) à mercure, qui m'ont des résultats si satisfaisants que je'un seul sens (on peut les faire marcher par un moteur); en outre, dans mes machines, le mercure, qui sert

Paris-Sud XI, Université de

170

Visualisation 3D de champs de vecteurs par diffusion anisotropique  

E-print Network

Visualisation 3D de champs de vecteurs par diffusion anisotropique Olivier Commowick & Gabriel Peyr avons impl´ement´e la diffusion puis la visualisation 3D par isosurfaces du r´esultat. Enfin, nous euclidiens 2D ou 3D ainsi que sur des surfaces. Cette application est importante en visualisation

Frey, Pascal

171

Promiscuous Stimulation of ParF Protein Polymerization by Heterogeneous Centromere Binding Factors  

Microsoft Academic Search

The segrosome is the nucleoprotein complex that mediates accurate segregation of bacterial plasmids. The segrosome of plasmid TP228 comprises ParF and ParG proteins that assemble on the parH centromere. ParF, which exemplifies one clade of the ubiquitous ParA superfamily of segregation proteins, polymerizes extensively in response to ATP binding. Polymerization is modulated by the ParG centromere binding factor (CBF). The

Cristina Machón; Timothy J. G. Fothergill; Daniela Barillà; Finbarr Hayes

2007-01-01

172

Dissection of the region of Pseudomonas aeruginosa ParA that is important for dimerization and interactions with its partner ParB  

PubMed Central

Pseudomonas aeruginosa ParA belongs to a large subfamily of Walker-type ATPases acting as partitioning proteins in bacteria. ParA has the ability to both self-associate and interact with its partner ParB. Analysis of the deletion mutants defined the part of the protein involved in dimerization and interactions with ParB. Here, a set of ParA alanine substitution mutants in the region between E67 and L85 was created and analysed in vivo and in vitro. All mutants impaired in dimerization (substitutions at positions M74, H79, Y82 and L84) were also defective in interactions with ParB, suggesting that ParA–ParB interactions depend on the ability of ParA to dimerize. Mutants with alanine substitutions at positions E67, C68, L70, E72, F76, Q83 and L85 were not impaired in dimerization, but were defective in interactions with ParB. The dimerization interface partly overlapped the pseudo-hairpin, involved in interactions with ParB. ParA mutant derivatives tested in vitro showed no defects in ATPase activity. Two parA alleles (parA84, whose product can neither self-interact nor interact with ParB, and parA67, whose product is impaired in interactions with ParB, but not in dimerization) were introduced into the P. aeruginosa chromosome by homologous gene exchange. Both mutants showed defective separation of ParB foci, but to different extents. Only PAO1161 parA84 was visibly impaired in terms of chromosome segregation, growth rate and motility, similar to a parA-null mutant. PMID:25139949

Bartosik, Aneta A.; Glabski, Krzysztof; Jecz, Paulina; Lasocki, Krzysztof; Mikosa, Malgorzata; Plochocka, Danuta; Thomas, Christopher M.

2014-01-01

173

Seasonal expression of KiSS-1 and the pituitary gonadotropins LH? and FSH? in adult male Libyan jird (Meriones libycus).  

PubMed

The molecular mechanisms operating on a seasonal time-scale and regulating functions such as reproduction are poorly understood in animals living in desert environments. Kisspeptin, the product of the KiSS-1 gene, plays a critical role in control of the hypothalamic-pituitary-gonad axis that orchestrates the reproductive system in vertebrates. We report a sequence analysis of KiSS-1 and the pituitary luteinising hormone-beta (LH?) and follicle-stimulating hormone-beta (FSH?) in the Libyan jird (Meriones libycus), a seasonal breeding rodent that is sexually active during spring and quiescent in fall. We also assessed gene expression by quantitative real-time reverse transcription-polymerase chain reaction during the non-breeding and breeding seasons. The KiSS-1 cDNA sequence analysis showed high homology between M. libycus and all other rodents (94%) and humans (92%). KiSS-1 expression was higher during the breeding season than that during the non-breeding season. In contrast, LH? and FSH? expression levels were higher during the non-breeding season in autumn and varied in an opposite manner with testicular, seminal vesicle weights and plasma testosterone levels. Our results extend the role for KiSS-1 in activating the HPG axis in this desert rodent in its natural biotope by relaying environmental cues as in other seasonal non-desert rodent models. PMID:24786546

Boufermes, R; Richard, N; Le Moguen, K; Amirat, Z; Khammar, F; Kottler, M L

2014-06-10

174

TMS suppression of right pars triangularis, but not pars opercularis, improves naming in aphasia.  

PubMed

This study sought to discover if an optimum 1 cm(2) area in the non-damaged right hemisphere (RH) was present, which could temporarily improve naming in chronic, nonfluent aphasia patients when suppressed with repetitive transcranial magnetic stimulation (rTMS). Ten minutes of slow, 1Hz rTMS was applied to suppress different RH ROIs in eight aphasia cases. Picture naming and response time (RT) were examined before, and immediately after rTMS. In aphasia patients, suppression of right pars triangularis (PTr) led to significant increase in pictures named, and significant decrease in RT. Suppression of right pars opercularis (POp), however, led to significant increase in RT, but no change in number of pictures named. Eight normals named all pictures correctly; similar to aphasia patients, RT significantly decreased following rTMS to suppress right PTr, versus right POp. Differential effects following suppression of right PTr versus right POp suggest different functional roles for these regions. PMID:21864891

Naeser, Margaret A; Martin, Paula I; Theoret, Hugo; Kobayashi, Masahito; Fregni, Felipe; Nicholas, Marjorie; Tormos, Jose M; Steven, Megan S; Baker, Errol H; Pascual-Leone, Alvaro

2011-12-01

175

Optimisation de procds de BIOdpollution des eaux souterraines contamines par des hydrocarbures par un monitoring  

E-print Network

BIOPHY est de développer une nouvelle filière de traitement in situ de nappe basée sur : le surveillance (géophysiques et d'analyse de gaz) pour optimiser des bio-traitements de sol et de nappe de la dépollution des nappes d'eau souterraine, contaminées par des mélanges de composés organiques d

Demouchy, Sylvie

176

Novel Role for Proteinase-activated Receptor 2 (PAR2) in Membrane Trafficking of Proteinase-activated Receptor 4 (PAR4)*  

PubMed Central

Proteinase-activated receptors 4 (PAR4) is a class A G protein-coupled receptor (GPCR) recognized through the ability of serine proteases such as thrombin and trypsin to mediate receptor activation. Due to the irreversible nature of activation, a fresh supply of receptor is required to be mobilized to the cell surface for responsiveness to agonist to be sustained. Unlike other PAR subtypes, the mechanisms regulating receptor trafficking of PAR4 remain unknown. Here, we report novel features of the intracellular trafficking of PAR4 to the plasma membrane. PAR4 was poorly expressed at the plasma membrane and largely retained in the endoplasmic reticulum (ER) in a complex with the COPI protein subunit ?-COP1. Analysis of the PAR4 protein sequence identified an arginine-based (RXR) ER retention sequence located within intracellular loop-2 (R183AR ? A183AA), mutation of which allowed efficient membrane delivery of PAR4. Interestingly, co-expression with PAR2 facilitated plasma membrane delivery of PAR4, an effect produced through disruption of ?-COP1 binding and facilitation of interaction with the chaperone protein 14-3-3?. Intermolecular FRET studies confirmed heterodimerization between PAR2 and PAR4. PAR2 also enhanced glycosylation of PAR4 and activation of PAR4 signaling. Our results identify a novel regulatory role for PAR2 in the anterograde traffic of PAR4. PAR2 was shown to both facilitate and abrogate protein interactions with PAR4, impacting upon receptor localization and cell signal transduction. This work is likely to impact markedly upon the understanding of the receptor pharmacology of PAR4 in normal physiology and disease. PMID:22411985

Cunningham, Margaret R.; McIntosh, Kathryn A.; Pediani, John D.; Robben, Joris; Cooke, Alexandra E.; Nilsson, Mary; Gould, Gwyn W.; Mundell, Stuart; Milligan, Graeme; Plevin, Robin

2012-01-01

177

Étude par microscopie acoustique de couches minces de Ag2S déposées par spray  

NASA Astrophysics Data System (ADS)

Silver sulfide Ag2S thin films have been prepared on pyrex glass substrates by the spray pyrolysis technique at 250 °C. We have analyzed by acoustic microscopy and particularly by acoustic signature V(z) these films with various thickness (0.4 2 ?m). The acoustic signature, performed at 50, 130 and 570 MHz allow us to reach elastic properties of Ag2S material and specially Young modulus. Its value, of the order of 180 GPa, is consistent with the relative low linkage of Ag^+ in the structure and the character of fast-ion conductor of Ag2S. Besides elastic properties and using MEB and AFM investigations, we have shown that the V(z) signature gives valuable information about the bulk defects in the material. Finally, the experimental results have been discussed related to the dispersion curves of velocity of the first mode of Ag2S/pyrex system. Des couches minces de sulfure d'argent Ag2S sont préparées sur substrat de pyrex, à la température de 250 °C, par la technique de pulvérisation chimique réactive en phase liquide ou “spray". Ces dépôts, d'épaisseur variable (0,4 2 ?m), sont analysés par microscopie acoustique et, plus particulièrement, par la méthode de relevé de la signature acoustique V(z). Cette signature, effectuée à différentes fréquences (50, 130, 570 MHz), a permis de caractériser les propriétés élastiques du matériau Ag2S. La valeur du module d'Young, de l'ordre de 180 GPa, est en accord avec la faible cohésion de la liaison Ag-S et le caractère de conducteur ionique rapide de Ag2S. Les observations par MEB et AFM permettent d'expliquer l'allure des courbes V(z) par les défauts de compacité liés à la méthode de préparation. Les résultats expérimentaux sont discutés en liaison avec la courbe de dispersion de vitesses du premier mode du système Ag2S/pyrex.

Amlouk, M.; Brunet, N.; Cros, B.; Belgacem, S.; Barjon, D.

1997-09-01

178

Limnological database for Par Pond: 1959 to 1980  

SciTech Connect

A limnological database for Par Pond, a cooling reservoir for hot reactor effluent water at the Savannah River Plant, is described. The data are derived from a combination of research and monitoring efforts on Par Pond since 1959. The approximately 24,000-byte database provides water quality, primary productivity, and flow data from a number of different stations, depths, and times during the 22-year history of the Par Pond impoundment. The data have been organized to permit an interpretation of the effects of twenty years of cooling system operations on the structure and function of an aquatic ecosystem.

Tilly, L.J.

1981-03-01

179

LETTRES A LA RDACTION REDRESSEMENT PAR CONTACT SUR LE TELLURE  

E-print Network

'extraction et revêtus d'une couche d'oxyde : Mg, Ca, Ba, Sr, Li, Na, K; les métaux Zn, Be, Al sont dans un cas, débitanti mA redressé sous I V maximum; on favorise le redressement par Zif en l'oxydant en surface par NO3H couche d'oxyde recouvrant le métal; ces oxydes, comme BaO, MgO, ZnO, peuvent devenir de type n par excès

Boyer, Edmond

180

Effect of nutrition on seasonal patterns of LH, FSH and testosterone concentration, testicular mass, sebaceous gland volume and odour in Australian Cashmere goats.  

PubMed

The effects of season and diet on LH, FSH and testosterone concentrations, testicular mass, sebaceous gland volume and male odour were examined in mature Australian cashmere goat bucks fed ad libitum with diets of low or high quality for 16 months under natural photoperiod at 29 degrees S, 153 degrees E (n = 6 per treatment). Each week plasma was sampled, the bucks were weighed, scored for male odour and assessed for testicular mass based on scrotal circumference. Each month a skin sample was taken from the occipital region for histological assessment of sebaceous gland volume. For each variable there was a clear circannual cycle that was significantly influenced by dietary treatment. In bucks fed the low-quality diet, the timing of seasonal changes in LH and testosterone concentration, sebaceous gland volume and odour score was similar, with a mid-autumn peak. In each case the high-quality diet advanced, extended the duration and increased the magnitude of the seasonal increase. FSH concentrations peaked in late spring (in bucks on the high-quality diet) or summer (in bucks on the low-quality diet), reaching a nadir in early winter. The high-quality diet significantly increased concentrations only in the last 2 months of the experiment (spring). There was no overall association between these variables and change in testicular mass; instead, it was strongly correlated with voluntary feed intake and change in body mass, themselves subject to seasonal variation with a winter or spring peak. The high-quality diet induced large increases in body mass and testicular mass during the first months of the experiment without influencing the seasonally low concentrations of FSH, LH and testosterone present at the time. These results demonstrate that the male, like the female, Australian cashmere goat, exhibits marked reproductive seasonality, and that nutrition is a powerful modulator of the seasonal cycle. They suggest that testosterone concentration, sebaceous gland volume and odour score are ultimately dependent upon LH secretion, which appears to be under strong seasonal (photoperiodic) control, with the effects of enhanced nutrition limited to periods when photoperiodic inhibition is waning. However, seasonal regulation of testicular mass, and therefore sperm production, appears to be primarily dependent on changes in voluntary feed intake and growth, with the seasonal cycle of testicular mass more a consequence of the seasonal appetite or growth cycle than of changing gonadotrophin concentrations. PMID:7861388

Walkden-Brown, S W; Restall, B J; Norton, B W; Scaramuzzi, R J; Martin, G B

1994-11-01

181

Passivation de l'InP par oxydation en plasma RF oxygne et par action de HNO3 vapeur  

E-print Network

745 Passivation de l'InP par oxydation en plasma RF oxygène et par action de HNO3 vapeur C. Michel.S.I.N., 54500 Vandoeuvre, France (Reçu le 25 juillet 1983, accepté le 13 septembre 1983) Résumé. - Des oxydes à des températures allant jusqu'à 200°C. Les propriétés de ces oxydes ont été étudiées par ellipso

Paris-Sud XI, Université de

182

The role of uPAR signaling in lung cancer Background and significance  

E-print Network

The role of uPAR signaling in lung cancer Background and significance Lung cancer is the leading-like properties. Recently, our lab has discovered that the urokinase (uPA) receptor (uPAR) has the ability uPAR (Gutova et al., 2007). These studies led me to hypothesize that uPAR is involved in inducing

Gleeson, Joseph G.

183

View from southwest to northeast of PAR site fresh water ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View from southwest to northeast of PAR site fresh water pump house - Stanley R. Mickelsen Safeguard Complex, Fresh Water Pump House, In Limited Access Area, on Patrol Road next to Open Storage Reservoir No. 736, Nekoma, Cavalier County, ND

184

The Pars Triangularis in Dyslexia and ADHD  

PubMed Central

Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one of the purposes of this study was to examine the structure of the PT in dyslexia and ADHD. The other purposes included examining the PT in relation to overall expressive language ability and in relation to several specific linguistic functions given language functioning often is affected in both dyslexia and ADHD. Participants included 50 children: 10 with dyslexia, 15 with comorbid dyslexia/ADHD, 15 with ADHD, and 10 controls. Using a 2 (dyslexia or not) X 2 (ADHD or not) MANCOVA, findings revealed PT length and shape were comparable between those with and without dyslexia. However, children with ADHD had smaller right PT lengths than those without ADHD, and right anterior ascending ramus length was related to attention problems in the total sample. In terms of linguistic functioning, presence of an extra sulcus in the left PT was related to poor expressive language ability. In those with adequate expressive language functioning, left PT length was related to phonological awareness, phonological short-term memory and rapid automatic naming (RAN). Right PT length was related to RAN and semantic processing. Further work on PT morphology in relation to ADHD and linguistic functioning is warranted. PMID:19356794

Kibby, Michelle Y.; Kroese, Judith M.; Krebbs, Hillery; Hill, Crystal E.; Hynd, George W.

2009-01-01

185

Scheduling on the MasPar SIMD parallel computer  

E-print Network

THE SCHEDULING ALGORITHMS A. Terminology B. Highest Level First Algorithm . C. Coffman/Graham Algorithm D. Clustering Algorithms III THE IVIASPAR. PARALLEL COMPUTER. A. MasPar Hardware B. MPL Programming Language C. Limitations IV PROGRAM DETAILS . A... THE SCHEDULING ALGORITHMS A. Terminology B. Highest Level First Algorithm . C. Coffman/Graham Algorithm D. Clustering Algorithms III THE IVIASPAR. PARALLEL COMPUTER. A. MasPar Hardware B. MPL Programming Language C. Limitations IV PROGRAM DETAILS . A...

Perkins, Keith Douglas

2012-06-07

186

Another application for trellis shaping: PAR reduction for DMT (OFDM)  

Microsoft Academic Search

A bound for the possible reduction of the peak-to-average ratio (PAR) dependent on the rate as well as possible practical procedures are presented. The idea of trellis shaping, originally used to minimize average transmit power in single-carrier systems, is applied to the problem of PAR reduction in multicarrier transmission. Its impact, as a function of code rate, as well as

Werner Henkel; Björn Wagner

2000-01-01

187

StePar: an automatic code for stellar parameter determination  

NASA Astrophysics Data System (ADS)

We introduce a new automatic code (StePar) for determinig stellar atmospheric parameters (T_{eff}, log{g}, ? and [Fe/H]) in an automated way. StePar employs the 2002 version of the MOOG code (Sneden 1973) and a grid of Kurucz ATLAS9 plane-paralell model atmospheres (Kurucz 1993). The atmospheric parameters are obtained from the EWs of 263 Fe I and 36 Fe II lines (obtained from Sousa et al. 2008, A&A, 487, 373) iterating until the excitation and ionization equilibrium are fullfilled. StePar uses a Downhill Simplex method that minimizes a quadratic form composed by the excitation and ionization equilibrium conditions. Atmospheric parameters determined by StePar are independent of the stellar parameters initial-guess for the problem star, therefore we employ the canonical solar values as initial input. StePar can only deal with FGK stars from F6 to K4, also it can not work with fast rotators, veiled spectra, very metal poor stars or Signal to noise ratio below 30. Optionally StePar can operate with MARCS models (Gustafson et al. 2008, A&A, 486, 951) instead of Kurucz ATLAS9 models, additionally Turbospectrum (Alvarez & Plez 1998, A&A, 330, 1109) can replace the MOOG code and play its role during the parameter determination. StePar has been used to determine stellar parameters for some studies (Tabernero et al. 2012, A&A, 547, A13; Wisniewski et al. 2012, AJ, 143, 107). In addition StePar is being used to obtain parameters for FGK stars from the GAIA-ESO Survey.

Tabernero, H. M.; González Hernández, J. I.; Montes, D.

2013-05-01

188

Explication de décrues anormales par modèles analogiques de réservoirs  

Microsoft Academic Search

Des modèles analogiques de réservoirs ont été élaborés à partir de l'analyse de débits de décrue de deux sources karstiques. La première source est caractérisée par une linéarité entre le débit et le temps; la seconde l'est par une loi en puissance. Pour les deux sources, il n'y a pas linéarité entre le volume d'eau souterraine stocké et le débit

Erick Carlier; Lahcen Zouhri; Isam Shahrour

2012-01-01

189

Reproductive Physiology in Young Men Is Cumulatively Affected by FSH-Action Modulating Genetic Variants: FSHR -29G/A and c.2039 A/G, FSHB -211G/T  

PubMed Central

Follicle-Stimulating Hormone Receptor (FSHR) -29G/A polymorphism (rs1394205) was reported to modulate gene expression and reproductive parameters in women, but data in men is limited. We aimed to bring evidence to the effect of FSHR -29G/A variants in men. In Baltic young male cohort (n?=?982; Estonians, Latvians, Lithuanians; aged 20.2±2.0 years), the FSHR -29 A-allele was significantly associated with higher serum FSH (linear regression: effect 0.27 IU/L; P?=?0.0019, resistant to Bonferroni correction for multiple testing) and showed a non-significant trend for association with higher LH (0.19 IU/L) and total testosterone (0.93 nmol/L), but reduced Inhibin B (?7.84 pg/mL) and total testes volume (effect ?1.00 mL). Next, we extended the study and tested the effect of FSHR gene haplotypes determined by the allelic combination of FSHR -29G/A and a well-studied variant c.2039 A/G (Asn680Ser, exon 10). Among the FSHR -29A/2039G haplotype carriers (A-Ser; haplotype-based linear regression), this genetic effect was enhanced for FSH (effect 0.40 IU/L), Inhibin B (?16.57 pg/mL) and total testes volume (?2.34 mL). Finally, we estimated the total contribution of three known FSH-action modulating SNPs (FSHB -211G/T; FSHR -29G/A, c.2039 A/G) to phenotypic variance in reproductive parameters among young men. The major FSH-action modulating SNPs explained together 2.3%, 1.4%, 1.0 and 1.1% of the measured variance in serum FSH, Inhibin B, testosterone and total testes volume, respectively. In contrast to the young male cohort, neither FSHR -29G/A nor FSHR haplotypes appeared to systematically modulate the reproductive physiology of oligozoospermic idiopathic infertile patients (n?=?641, Estonians; aged 31.5±6.0 years). In summary, this is the first study showing the significant effect of FSHR -29G/A on male serum FSH level. To account for the genetic effect of known common polymorphisms modulating FSH-action, we suggest haplotype-based analysis of FSHR SNPs (FSHR -29G/A, c.2039 A/G) in combination with FSHB -211G/T testing. PMID:24718625

Grigorova, Marina; Punab, Margus; Punab, Anna Maria; Poolamets, Olev; Vihljajev, Vladimir; Zilaitiene, Birute; Erenpreiss, Juris; Matulevicius, Valentinas; Laan, Maris

2014-01-01

190

Sur l'ionisation de l'atmosphre par les substances radioactives1 Par A. S. EVE  

E-print Network

cette quantité d'émanation correspond environ a la 1 1011 partie de I'atlnosphére. D'après Rutherford et seconde ou 1,65 ion par cm3 et par seconde. Rayons u du thorium. Il n'est pas possible actuellement de faire un calcul analogue pour le cas du thorium. Tout ce qu'on sait, c'est que le dépôt actif du thorium

Paris-Sud XI, Université de

191

The double par locus of virulence factor pB171: DNA segregation is correlated with oscillation of ParA.  

PubMed

Prokaryotic plasmids and chromosomes encode partitioning (par) loci that segregate DNA to daughter cells before cell division. Recent database analyses showed that almost all known par loci encode an ATPase and a DNA-binding protein, and one or more cis-acting regions where the proteins act. All par-encoded ATPases belong to one of two protein superfamilies, Walker-type and actin-like ATPases. This property was recently used to divide par loci into Types I and II loci. We show here that the Escherichia coli virulence factor pB171 encodes a double par locus that consists of one Type I and one Type II locus. Separately, each locus stabilized a test-plasmid efficiently. Together, the two loci mediated even more efficient plasmid stabilization. The par loci have a unique genetic organization in that they share a common central region at which the two different DNA-binding proteins probably act. Interestingly, a fusion protein consisting of the Walker-type ParA ATPase and Gfp was functional and oscillated in nucleoid regions on a time scale of minutes. ParA-green fluorescent protein (Gfp) oscillation depended on both ParB and parC but was independent of minCDE. Point mutations in the Walker A box motif simultaneously abolished plasmid stabilization and ParA-Gfp oscillation. These observations raise the possibility that ParA oscillation is prerequisite for active plasmid segregation. PMID:11752455

Ebersbach, G; Gerdes, K

2001-12-18

192

The double par locus of virulence factor pB171: DNA segregation is correlated with oscillation of ParA  

PubMed Central

Prokaryotic plasmids and chromosomes encode partitioning (par) loci that segregate DNA to daughter cells before cell division. Recent database analyses showed that almost all known par loci encode an ATPase and a DNA-binding protein, and one or more cis-acting regions where the proteins act. All par-encoded ATPases belong to one of two protein superfamilies, Walker-type and actin-like ATPases. This property was recently used to divide par loci into Types I and II loci. We show here that the Escherichia coli virulence factor pB171 encodes a double par locus that consists of one Type I and one Type II locus. Separately, each locus stabilized a test-plasmid efficiently. Together, the two loci mediated even more efficient plasmid stabilization. The par loci have a unique genetic organization in that they share a common central region at which the two different DNA-binding proteins probably act. Interestingly, a fusion protein consisting of the Walker-type ParA ATPase and Gfp was functional and oscillated in nucleoid regions on a time scale of minutes. ParA-green fluorescent protein (Gfp) oscillation depended on both ParB and parC but was independent of minCDE. Point mutations in the Walker A box motif simultaneously abolished plasmid stabilization and ParA-Gfp oscillation. These observations raise the possibility that ParA oscillation is prerequisite for active plasmid segregation. PMID:11752455

Ebersbach, Gitte; Gerdes, Kenn

2001-01-01

193

Par Pond vegetation status Summer 1995 -- June survey descriptive summary  

SciTech Connect

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the shoreline aquatic plant communities in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level, indicated that much of the original plant communities and the intermediate shoreline communities present on the exposed sediments have been lost. The extensive old-field and emergent marsh communities that were present on the exposed shoreline during the drawdown have been flooded and much of the pre-drawdown Par Pond aquatic plant communities have not had sufficient time for re-establishment. The shoreline does, however, have extensive beds of maidencane which extend from the shoreline margin to areas as deep as 2 and perhaps 3 meters. Scattered individual plants of lotus and watershield are common and may indicate likely directions of future wetland development in Par Pond. In addition, within isolated coves, which apparently received ground water seepage and/or stream surface flows during the period of the Par Pond draw down, extensive beds of waterlilies and spike rush are common. Invasion of willow and red maple occurred along the lake shoreline as well. Although not absent from this survey, evidence of the extensive redevelopment of the large cattail and eel grass beds was not observed in this first survey of Par Pond. Future surveys during the growing seasons of 1995, 1996, and 1997 along with the evaluation of satellite date to map the areal extent of the macrophyte beds of Par Pond are planned.

Mackey, H.E. Jr.; Riley, R.S.

1995-06-01

194

Both PHYTOCHROME RAPIDLY REGULATED1 (PAR1) and PAR2 Promote Seedling Photomorphogenesis in Multiple Light Signaling Pathways1[C][W][OPEN  

PubMed Central

Arabidopsis (Arabidopsis thaliana) seedlings undergo photomorphogenesis in the light and etiolation in the dark. Light-activated photoreceptors transduce the light signals through a series of photomorphogenesis promoting or repressing factors to modulate many developmental processes in plants, such as photomorphogenesis and shade avoidance. CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) is a conserved RING finger E3 ubiquitin ligase, which mediates degradation of several photomorphogenesis promoting factors, including ELONGATED HYPOCOTYL5 (HY5) and LONG HYPOCOTYL IN FAR-RED1 (HFR1), through a 26S proteasome-dependent pathway. PHYTOCHROME RAPIDLY REGULATED1 (PAR1) was first detected as an early repressed gene in both phytochrome A (phyA)-mediated far-red and phyB-mediated red signaling pathways, and subsequent studies showed that both PAR1 and PAR2 are negative factors of shade avoidance in Arabidopsis. However, the role of PAR1 and PAR2 in seedling deetiolation, and their relationships with other photomorphogenesis promoting and repressing factors are largely unknown. Here, we confirmed that both PAR1 and PAR2 redundantly enhance seedling deetiolation in multiple photoreceptor signaling pathways. Their transcript abundances are repressed by phyA, phyB, and cryptochrome1 under far-red, red, and blue light conditions, respectively. Both PAR1 and PAR2 act downstream of COP1, and COP1 mediates the degradation of PAR1 and PAR2 through the 26S proteasome pathway. Both PAR1 and PAR2 act in a separate pathway from HY5 and HFR1 under different light conditions, except for sharing in the same pathway with HFR1 under far-red light. Together, our results substantiate that PAR1 and PAR2 are positive factors functioning in multiple photoreceptor signaling pathways during seedling deetiolation. PMID:24335334

Zhou, Peng; Song, Meifang; Yang, Qinghua; Su, Liang; Hou, Pei; Guo, Lin; Zheng, Xu; Xi, Yulin; Meng, Fanhua; Xiao, Yang; Yang, Li; Yang, Jianping

2014-01-01

195

Bacillus subtilis Soj (ParA): The involvement of DNA binding and dynamic localization in plasmid partitioning  

E-print Network

The ParA family of ATPases encompasses proteins with a wide variety of functions. The prototype of this family is the ParA ATPase from the P1 prophage plasmid, which, along with ParB and the parS binding site, is required ...

Hester, Christina Marie

2008-05-08

196

Par Pond vegetation status Summer 1995 -- October survey descriptive summary  

SciTech Connect

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this late October survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maiden cane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

Mackey, H.E. Jr.; Riley, R.S.

1995-11-01

197

Par Pond vegetation status Summer 1995 -- September survey descriptive summary  

SciTech Connect

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this mid-September survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maidencane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys during the late growing seasons of 1995, and throughout 1996 and 1997, along with the evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

Mackey, H.E. Jr.; Riley, R.S.

1995-09-01

198

Dual modulation by thrombin of the motility of rat oesophageal muscularis mucosae via two distinct protease-activated receptors (PARs): a novel role for PAR-4 as opposed to PAR-1  

PubMed Central

Since protease-activated receptors (PARs) are distributed throughout the gastrointestinal tract, we investigated the role of PARs in modulation of the motility of the rat oesophageal muscularis mucosae. Thrombin produced contraction of segments of the upper and lower part of the smooth muscle. Trypsin contracted both the muscle preparations only at high concentrations. SFLLR-NH2 and TFLLR-NH2 (PAR-1-activating peptides), but not the PAR-1-inactive peptide FSLLR-NH2, evoked a marked contraction. In contrast, the PAR-2 agonist SLIGRL-NH2 and the PAR-4 agonist GYPGKF-NH2 caused no or only a negligible contraction. In oesophageal preparations precontracted with carbachol, thrombin produced a dual action i.e. relaxation followed by contraction. TFLLR-NH2 further contracted the precontracted preparations with no preceding relaxation. GYPGKF-NH2, but not the inactive peptide GAPGKF-NH2, produced marked relaxation. Trypsin or SLIGRL-NH2 caused no relaxation. The PAR-1-mediated contraction was completely abolished in Ca2+-free medium and considerably attenuated by nifedipine (1??M) and in a low Na+ medium. The PAR-4-mediated relaxation was resistant to tetrodotoxin (10??M), apamin (0.1??M), charybdotoxin (0.1??M), L-NG-nitroarginine methyl ester (100??M), indomethacin (3??M), propranolol (5??M) or adenosine 3?,5?-cyclic monophosphorothioate, 8-bromo, Rp-isomer (30??M). Thus, thrombin plays a dual role in modulating the motility of the oesophageal muscularis mucosae, producing contraction via PAR-1 and relaxation via PAR-4. The PAR-1-mediated effect appears to occur largely through increased Na+ permeability followed by activation of L-type Ca2+ channels and subsequent influx of extracellular Ca2+. Our data could provide evidence for a novel role of PAR-4 as opposed to PAR-1, although the underlying mechanisms are still open to question. PMID:11015310

Kawabata, Atsufumi; Kuroda, Ryotaro; Kuroki, Naoko; Nishikawa, Hiroyuki; Kawai, Kenzo

2000-01-01

199

Gene expression analysis of bovine oocytes at optimal coasting time combined with GnRH antagonist during the no-FSH period.  

PubMed

Ovarian stimulation with FSH combined with an appropriate period of FSH withdrawal (coasting) before ovum pick-up now appears to be a successful way to obtain oocytes with high developmental competence in bovine. Recent results showed that extending follicular growth by only 24 hours has a detrimental effect on oocyte quality as shown by the reduced blastocyst formation rate. Although these treatments are initiated during the luteal phase with low LH level, the small LH pulsatility present at that time could potentially impact follicular development as well as oocyte quality. In this study, a GnRH antagonist (Cetrotide) was used to suppress LH secretion during follicular differentiation to get a better insight into the physiological importance of the LH support during that period. Oocytes were collected by ovum pick-up, and quality was assessed by measuring the blastocyst formation rate obtained after IVM-IVF. The oocyte transcriptome from GnRH antagonist-treated animals was also compared with that from a control group (coasting duration of 68 hours) to detect possible alterations at the messenger RNA (mRNA) level. The oocyte quality was not statistically affected by the treatment as shown by the blastocyst formation rate obtained. However, microarray analysis showed that a total of 226 genes had a significant difference (fold change > 2; P < 0.05) at the mRNA level, with the majority being in overabundance in the treated group. Many genes related to RNA posttranscriptional modifications presented different abundance at the mRNA level significant differences in the control group (68 hours), whereas translation function appeared to be affected, with many genes related to structural constituents of the ribosome presenting a overabundance in the GnRH antagonist-treated group. Specific mRNAs with crucial roles in chromosome segregation control also showed significant difference at the mRNA level after Cetrotide treatment. The results presented here indicated that the suppression of the LH secretion in an optimal stimulated context would have an impact on the oocyte, with the possible alteration of critical functions related to translation capacity and chromosome segregation control. PMID:24581583

Labrecque, Rémi; Vigneault, Christian; Blondin, Patrick; Sirard, Marc-André

2014-05-01

200

Promiscuous stimulation of ParF protein polymerization by heterogeneous centromere binding factors.  

PubMed

The segrosome is the nucleoprotein complex that mediates accurate segregation of bacterial plasmids. The segrosome of plasmid TP228 comprises ParF and ParG proteins that assemble on the parH centromere. ParF, which exemplifies one clade of the ubiquitous ParA superfamily of segregation proteins, polymerizes extensively in response to ATP binding. Polymerization is modulated by the ParG centromere binding factor (CBF). The segrosomes of plasmids pTAR, pVT745 and pB171 include ParA homologues of the ParF subgroup, as well as diverse homodimeric CBFs with no primary sequence similarity to ParG, or each other. Centromere binding by these analogues is largely specific. Here, we establish that the ParF homologues of pTAR and pB171 filament modestly with ATP, and that nucleotide hydrolysis is not required for this polymerization, which is more prodigious when the cognate CBF is also present. By contrast, the ParF homologue of plasmid pVT745 did not respond appreciably to ATP alone, but polymerized extensively in the presence of both its cognate CBF and ATP. The co-factors also stimulated nucleotide-independent polymerization of cognate ParF proteins. Moreover, apart from the CBF of pTAR, the disparate ParG analogues promoted polymerization of non-cognate ParF proteins suggesting that filamentation of the ParF proteins is enhanced by a common mechanism. Like ParG, the co-factors may be modular, possessing a centromere-specific interaction domain linked to a flexible region containing determinants that promiscuously stimulate ParF polymerization. The CBFs appear to function as bacterial analogues of formins, microtubule-associated proteins or related ancillary factors that regulate eucaryotic cytoskeletal dynamics. PMID:17920627

Machón, Cristina; Fothergill, Timothy J G; Barillà, Daniela; Hayes, Finbarr

2007-11-16

201

Effect of FSH, LH, LH-RH and arginine-vasotocin on the production of steroids, nonapeptide hormones and cGMP by rabbits granulosa cells isolated at different stages of reproductive cycle.  

PubMed

Granulosa cells isolated from ovaries of non-cycling, cycling and pregnant rabbits of the same age were cultured in vitro either without or with pFSH (1 micrograms/ml), bLH (1 IU/ml), LH-RH (25 ng/ml) or arginine-8-vasotocin (100 ng/ml). The production of immunoreactive progesterone, estradiol-17 beta, oxytocin, arginine-8-vasopressin and cGMP was analyzed. The gonadotropins did not show any significant effects on the cells isolated from non-cycling and cycling rabbits, but not from these of pregnant ones. LH-RH inhibited and vasotocin stimulated progesterone production. All hormones used stimulated estradiol release from cells of non-cycling rabbits, while in a case of cycling animals no change was found. In the cell from pregnant females the release of estradiol was enhanced after LH treatment only. The treatment with FSH and LH (but not with LH-RH or vasotocin) resulted in a remarkable rise of granulosa vasopressin surge irrespectively to the reproductive stage. Oxytocin production by granulosa cells incubated either without or with LH, LH-RH or vasotocin was undetectable. However, FSH strongly stimulated oxytocin release. FSH and in lesser extent, LH or LH-RH (but not vasotocin) activated granulosa cGMP production in the cells from cycling and pregnant (but not from non-cycling) animals. It was also found that, in contrast to other reproductive stages, basal progesterone release from the cells of pregnant rabbits was increased, while in a case of non-cycling animals the basal estradiol release was decreased and that of cGMP was increased.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1335299

Nitray, J; Sirotkin, A; RaFay, J

1992-06-01

202

Urokinase Plasminogen Activator Receptor (uPAR) Targeted Nuclear Imaging and Radionuclide Therapy  

PubMed Central

Urokinase-type plasminogen activator receptor (uPAR) is a glycosylphosphatidylinositol (GPI)-anchored protein. Besides regulating proteolysis, uPAR could also activate many intracellular signaling pathways that promote cell motility, invasion, proliferation, and survival through cooperating with transmembrane receptors. uPAR is overexpressed across a variety of tumors and is associated with cancer invasion and metastasis. In order to meet the demand for a rapid development and potential clinical application of anti-cancer therapy based on uPA/uPAR system, it is desirable to develop non-invasive imaging methods to visualize and quantify uPAR expression in vivo. In this review, we will discuss recent advances in the development of uPAR-targeted nuclear imaging and radionuclide therapy agents. The successful development of molecular imaging probes to visualize uPAR expression in vivo would not only assist preclinical researches on uPAR function, but also eventually impact patient management. PMID:23843898

Li, Dan; Liu, Shuanglong; Shan, Hong; Conti, Peter; Li, Zibo

2013-01-01

203

FSH receptor (FSHR) expression in human extragonadal reproductive tissues and the developing placenta, and the impact of its deletion on pregnancy in mice.  

PubMed

Expression and function of the follicle-stimulating hormone receptor (FSHR) in females were long thought to be limited to the ovary. Here, however, we identify extragonadal FSHR in both the human female reproductive tract and the placenta, and test its physiological relevance in mice. We show that in nonpregnant women FSHR is present on: endothelial cells of blood vessels in the endometrium, myometrium, and cervix; endometrial glands of the proliferative and secretory endometrium; cervical glands and the cervical stroma; and (at low levels) stromal cells and muscle fibers of the myometrium. In pregnant women, placental FSHR was detected as early as 8-10 wk of gestation and continued through term. It was expressed on: endothelial cells in fetal portions of the placenta and the umbilical cord; epithelial cells of the amnion; decidualized cells surrounding the maternal arteries in the maternal decidua; and the stromal cells and muscle fibers of the myometrium, with particularly strong expression at term. These findings suggest that FSHR expression is upregulated during decidualization and upregulated in myometrium as a function of pregnancy. The presence of FSHR in the placental vasculature suggests a role in placental angiogenesis. Analysis of genetically modified mice in which Fshr is lacking in fetal portions of the placenta revealed adverse effects on fetoplacental development. Our data further demonstrate FSHB and CGA mRNAs in placenta and uterus, consistent with potential local sources of FSH. Collectively, our data suggest heretofore unappreciated roles of extragonadal FSHR in female reproductive physiology. PMID:25100706

Stilley, Julie A W; Christensen, Debora E; Dahlem, Kristin B; Guan, Rongbin; Santillan, Donna A; England, Sarah K; Al-Hendy, Ayman; Kirby, Patricia A; Segaloff, Deborah L

2014-09-01

204

Arylquins target vimentin to trigger Par-4 secretion for tumor cell apoptosis.  

PubMed

The tumor suppressor protein prostate apoptosis response-4 (Par-4), which is secreted by normal cells, selectively induces apoptosis in cancer cells. We identified a 3-arylquinoline derivative, designated Arylquin 1, as a potent Par-4 secretagogue in cell cultures and mice. Mechanistically, Arylquin 1 binds vimentin, displaces Par-4 from vimentin for secretion and triggers the efficient paracrine apoptosis of diverse cancer cells. Thus, targeting vimentin with Par-4 secretagogues efficiently induces paracrine apoptosis of tumor cells. PMID:25218743

Burikhanov, Ravshan; Sviripa, Vitaliy M; Hebbar, Nikhil; Zhang, Wen; Layton, W John; Hamza, Adel; Zhan, Chang-Guo; Watt, David S; Liu, Chunming; Rangnekar, Vivek M

2014-11-01

205

Contact : alice.desclaux@ird.fr Financement : Les perceptions des lipodystrophies par les personnes atteintes Dakar  

E-print Network

51 Contact : alice.desclaux@ird.fr Financement : Les perceptions des lipodystrophies par les.desclaux@ird.fr 2. CRCF, Dakar, Sénégal Introduction et objectifs Les lipodystrophies sont définies par la médecine lipodystrophies cliniques (perçues par le médecin ou par elles-mêmes) (Diouf 2011). Les lipodystrophies se

Paris-Sud XI, Université de

206

Class 8. Telomeres and PAR October 5, 2009 Boyd, et al., 1996  

E-print Network

Class 8. Telomeres and PAR October 5, 2009 1 Telomeres A model Boyd, et al., 1996 #12;Class 8. Telomeres and PAR October 5, 2009 2 Spatial cue -> polarity Cuenca, A. A. et al. Development 2003://ftp.wormbase.org/pub/wormbase/datasets/seydoux_2003/MOVIE02%20PAR-6.mov #12;Class 8. Telomeres and PAR October 5, 2009 3 Cuenca, A. A. et al

Devoto, Stephen H.

207

Free fatty acids induce Lhb mRNA but suppress Fshb mRNA in pituitary L?T2 gonadotropes and diet-induced obesity reduces FSH levels in male mice and disrupts the proestrous LH/FSH surge in female mice.  

PubMed

Female obesity is associated with insulin resistance, hyperandrogenemia, and reproductive dysfunction. We hypothesized that elevated free fatty acids (FFAs) might directly modulate pituitary gonadotropin production. FFAs caused a time- and dose-dependent increase in phosphorylation of the MAPKs p38MAPK, c-Jun N-terminal kinase (JNK)-1/2, and ERK1/2 in L?T2 gonadotrope cells. Furthermore, FFAs up-regulated Lhb mRNA expression acutely, an effect that was blocked by JNK inhibition, but suppressed Fshb mRNA expression, an effect that was independent of MAPK signaling. FFAs enhanced the activation of the MAPKs in the presence of GnRH, although the cotreatment did not alter Lhb induction but did eliminate the GnRH induction of Fshb. FFAs also suppressed activin-induced Fshb expression. Knockdown experiments showed that the FFA effect on the inflammatory kinases p38MAPK and JNK and on Lhb, but not Fshb, mRNA expression is mediated via toll-like receptor-2 and toll-like receptor-4 and was mimicked by lipopolysaccharide stimulation. In vivo, male C57BL/6 mice on a high-fat diet showed reduced FSH levels consistent with the suppression of Fshb seen in vitro. Histological analysis of the testes showed an increased number of abnormal seminiferous tubules. Female mice on a high-fat diet lacked the expected proestrus LH and FSH surge and exhibited an increase in the number of days at estrus and a reduced number of days at proestrus, and ovaries had significantly fewer corpora lutea. Taken together, our findings suggest that lipid excess can lead to reproductive defects in both male and female mice. PMID:23525221

Sharma, Shweta; Morinaga, Hidetaka; Hwang, Vicky; Fan, Wuqiang; Fernandez, Marina O; Varki, Nissi; Olefsky, Jerrold M; Webster, Nicholas J G

2013-06-01

208

Free Fatty Acids Induce Lhb mRNA but Suppress Fshb mRNA in Pituitary L?T2 Gonadotropes and Diet-Induced Obesity Reduces FSH Levels in Male Mice and Disrupts the Proestrous LH/FSH Surge in Female Mice  

PubMed Central

Female obesity is associated with insulin resistance, hyperandrogenemia, and reproductive dysfunction. We hypothesized that elevated free fatty acids (FFAs) might directly modulate pituitary gonadotropin production. FFAs caused a time- and dose-dependent increase in phosphorylation of the MAPKs p38MAPK, c-Jun N-terminal kinase (JNK)-1/2, and ERK1/2 in L?T2 gonadotrope cells. Furthermore, FFAs up-regulated Lhb mRNA expression acutely, an effect that was blocked by JNK inhibition, but suppressed Fshb mRNA expression, an effect that was independent of MAPK signaling. FFAs enhanced the activation of the MAPKs in the presence of GnRH, although the cotreatment did not alter Lhb induction but did eliminate the GnRH induction of Fshb. FFAs also suppressed activin-induced Fshb expression. Knockdown experiments showed that the FFA effect on the inflammatory kinases p38MAPK and JNK and on Lhb, but not Fshb, mRNA expression is mediated via toll-like receptor-2 and toll-like receptor-4 and was mimicked by lipopolysaccharide stimulation. In vivo, male C57BL/6 mice on a high-fat diet showed reduced FSH levels consistent with the suppression of Fshb seen in vitro. Histological analysis of the testes showed an increased number of abnormal seminiferous tubules. Female mice on a high-fat diet lacked the expected proestrus LH and FSH surge and exhibited an increase in the number of days at estrus and a reduced number of days at proestrus, and ovaries had significantly fewer corpora lutea. Taken together, our findings suggest that lipid excess can lead to reproductive defects in both male and female mice. PMID:23525221

Sharma, Shweta; Morinaga, Hidetaka; Hwang, Vicky; Fan, WuQiang; Fernandez, Marina O.; Varki, Nissi; Olefsky, Jerrold M.

2013-01-01

209

Microscopie fluorescence et tomographie par cohrence optique en plein champ  

E-print Network

gating property of light for FF-OCM, and structured illumination for fluorescence microscopy. The dual optically-sectioned fluorescence and optical coherence microscopy with full-field illumination) Full champ et microscopie à fluorescence par illumination structurée. 2.1 Partie du dispositif dédiée à l

Paris-Sud XI, Université de

210

The pars intermedia of the mink, Mustela vison  

Microsoft Academic Search

The pars intermedia of intact and experimental female minks has been studied by light, electron and fluorescence microscopy. The general structure of the mink intermediate lobe is described. Two main cell types are recognized. One, termed glandular cell, predominates in number and is characterized by the presence of electron-dense granules about 200 nm in diameter and numerous large vesicles up

B. Weman; A. Nobin

1973-01-01

211

Radiological impact of Par Pond drawdown from liquid effluent pathways  

SciTech Connect

The water level of Par Pond has been lowered over the past several months to reduce the effects in the event of catastrophic dam failure while assessing the condition of the dam and determining if repairs are necessary. In lowering the level of Par Pond, 60 billion liters of water containing low levels of tritium and cesium-137 were discharged to several onsite streams. SRS surface streams flow to the Savannah River. An assessment made to determine the total amount of tritium and Cs-137 discharged and to estimate the consequences to downstream Savannah River users. It is estimated that a total of 160 curies of tritium were displaced from Par Pond to the Savannah River between June 28, 1991 and September 19, 1991. This release could hypothetically result in a maximum individual dose of 3. 2{times}10{sup {minus}4} mrem and a total (80-km and drinking water populations) population dose of 1.4{times}10{sup {minus}2} person-rem. Likewise, a maximum individual dose of 5.0{times}10{sup {minus}2} mrem and a total population dose of 1.7{times}10{sup {minus}1} person- rem are predicted as a result of an estimated 0.21 curies of Cs-137 being discharged from Par Pond to the Savannah River.

Carlton, W.H.; Hamby, D.M.

1991-10-25

212

POLITIQUE SUR COMMUNICATIONS PAR COURRIER ELECTRONIQUE AVEC LES ETUDIANTS Approuve  

E-print Network

POLITIQUE SUR COMMUNICATIONS PAR COURRIER ELECTRONIQUE AVEC LES ETUDIANTS Approuvée : Sénat Le 17'Université McGill doit instaurer une politique officialisant l'usage du courrier électronique comme moyen de communication avec les étudiants. L'adoption du courrier électronique comme moyen de communication officiel

Barthelat, Francois

213

N d'ordre 197 -2011 Anne 2011 Dlivre par  

E-print Network

Sylvette BRUNET Rapporteur M. Franck DUMEIGNIL Rapporteur Mme Catherine PINEL Examinateur M. Arnaud TRAVERT Philippe Lecour pour les résultats de caractérisations par XPS et à Isabelle Clémençon pour les analyses

Paris-Sud XI, Université de

214

Magnétométrie à hélium par pompage laser: le bilan  

NASA Astrophysics Data System (ADS)

Depuis 1986, l'équipe Physique Atomique et Capteurs du CIRIL-ISMRA de Caen étudie les magnétomètres à hélium par pompage laser. On présente ici le bilan de ces travaux de recherche et les performances des deux prototypes (hélium4 et hélium3) réalisés au Laboratoire.

Gilles, H.; Hamel, J.; Monfort, Y.

2002-06-01

215

Par Pond vegetation status summer 1995 - July survey descriptive summary  

SciTech Connect

A survey of the emergent shoreline aquatic plant, communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet (61 meters) above mean sea level, and continued with this July survey. Aquatic plant communities, similar to the pre-drawdown Par Pond communities, are becoming reestablished. Beds of maidencane (Panicum hemitomon), lotus (Nelumbo lutea), water lily (Nymphaea odorata), and watershield (Brasenia schreberi) are now extensive and well established. In addition, within isolated coves, extensive beds of water lilies and spike-rush (Eleocharis sp.) are common. Cattail occurrence has increased since refill, but large beds common to Par Pond prior to the drawdown have not formed. Invasion of willow (Salix sp.) and red maple (Acer rubrum) occurred along the lake shoreline during drawdown. The red maples along the present shoreline are beginning to show evidence of stress and mortality from flooding over the past four months. Some of the willows appear to be stressed as well. The loblolly pines (Pinus taeda), which were flooded in all but the shallow shoreline areas, are now dead. Future surveys are planned for the growing seasons of 1995, 1996, and 1997, along with the evaluation of satellite data for mapping the areal extent of the macrophyte beds of Par Pond.

Mackey, H.E. Jr.; Riley, R.S.

1995-07-01

216

INSTITUT NATIONAL POLYTECHNIQUE DE GRENOBLE N attribu par la bibliothque  

E-print Network

Découverte de Topologie 23 2 Découverte de Topologie 25 2.1 Caractéristiques recherchées . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.2 Découverte de topologie et la structure du réseau . . . . . . . . . . . . . . . . . . . 26 2.2.1 Topologie fournie par l'utilisateur . . . . . . . . . . . . . . . . . . . . . . . 27 2.2.2 Protocoles de

Paris-Sud XI, Université de

217

Universit Paris 1 PanthonSorbonne prsent par  

E-print Network

Bordeaux 1 Examinateur Habilitation préparée au sein du laboratoire SAMM, Université Paris 1 Panthéon les membres du SAMM (et son annexe d'historiens du Pireh) pour ces (déjà) 6 années très agréables et

Paris-Sud XI, Université de

218

INSTITUT NATIONAL POLYTECHNIQUE DE GRENOBLE N attribu par la bibliothque  

E-print Network

présentée et soutenue publiquement par Ludovic MATHIEU le 26 Septembre 2005 Titre : Cycle Thorium et Réacteurs à Sel Fondu Exploration du champ des Paramètres et des Contraintes définissant le "Thorium Molten Salt Reactor" Directeur de thèse : Daniel HEUER JURY : Claude Renault rapporteur Jean-Claude Steckmeyer

Paris-Sud XI, Université de

219

Acetylcholinesterase in der Pars distalis von Zonotrichia leucophrys gambelii (Aves)  

Microsoft Academic Search

Photoperiodic stimulation of photosensitive male white-crowned sparrows, Zonotrichia leucophrys gambelii, causes the appearance of acetylcholinesterase activity in the cephalic and caudal lobes of the pars distalis. In photosensitive birds held on short daily photoperiods little or no activity can he demonstrated histochemically. The enzyme is restricted to PAS-positive cells. After attaining a maximum between 31 and 52 days after the

Eberhard Haase; Donald S. Farner

1969-01-01

220

Universit du Sud Toulon Var N attribu par la bibliothque  

E-print Network

» - Philip K. Dirk « Il s'agit plus de penser et d'agir autrement que davantage » ­ Patrick ZIMBARDO ... à publiquement le 8 décembre 2008 par Patrick ZIMBARDO sous la direction du Professeur Luc QUONIAM Composition du

Paris-Sud XI, Université de

221

Cheminement par trimestre --Baccalaurat en informatique La passerelle DEC informatique  

E-print Network

'adresse : http://admission.umontreal.ca/programmes/majeure-en-informatique/ structure-du-programme/. En plus desCheminement par trimestre -- Baccalauréat en informatique La passerelle DEC informatique Le baccalauréat en informatique Le baccalauréat en informatique mise sur les aspects fondamentaux de l'informatique

Montréal, Université de

222

Actes JFPC 2008 Hybridation de la programmation par contraintes  

E-print Network

Actes JFPC 2008 Hybridation de la programmation par contraintes et d'un voisinage à très grande taille pour Eternity II. Pierre Schaus Yves Deville Département d'ingénierie informatique, Université de

Deville, Yves

223

Cheminement par trimestre --Majeure en informatique La majeure en informatique  

E-print Network

systèmes ; - mathématiques appliquées à l'informatique et à l'optimisation. Ce programme aborde les disponible sur le site des admissions à l'adresse : http://admission.umontreal.ca/programmes/majeure-en-informatiqueCheminement par trimestre -- Majeure en informatique La majeure en informatique La majeure est

Montréal, Université de

224

Cheminement par trimestre --Mineure en informatique La mineure en informatique  

E-print Network

informatique. Ce programme est conçu pour être suivi concurremment avec une majeure ou d'autres mineures, et il du programme disponible sur le site des admissions à l'adresse : http://admission.umontreal.ca/programmes/majeure-en-informatiqueCheminement par trimestre -- Mineure en informatique La mineure en informatique La mineure est

Montréal, Université de

225

LUMINESCENCE DANS LES SOLIDES LECTRONIQUEMENT ACTIFS Par HUMBOLDT W. LEVERENZ,  

E-print Network

612. LUMINESCENCE DANS LES SOLIDES �LECTRONIQUEMENT ACTIFS Par HUMBOLDT W. LEVERENZ, R. C. A of solids and of luminescence. LI JOURNAL DE PHYSIQUE ET LE RADIUM TOME 17, AOUT-SEPTEMBRE 1956, PAGE 612 luminescence. 1. L'orientation des spins des atomes voisins,' parallèles ou antiparallèles, provoque le ferro

Paris-Sud XI, Université de

226

INFECTION EXPRIMENTALE DU BLIER PAR SALMONELLA ABORTUS OVIS  

E-print Network

INFECTION EXPÃ?RIMENTALE DU BÃ?LIER PAR SALMONELLA ABORTUS OVIS R. SANCHIS P. PARDON2 Georgette, France Summary EXPERIMENTAL INFECTION OF RAM WITH SALMONELLA ABORTUS OVIS. - The susceptibility of rams to experimental challenge with Salmonella abortus ovis was investigated by subcutaneous, conjunctival or preputial

Paris-Sud XI, Université de

227

Les grands sismes mesurs par satellites Christophe Vigny*  

E-print Network

of France d1 d2 d1 Satellite Laser Ranging (SLR) High energy laser firing at satellites enableLes grands séismes mesurés par satellites Christophe Vigny* *département des Geosciences de l to determine the position of the satellite and then the Geoid, assuming the station position is know

Vigny, Christophe

228

BOREAS RSS-10 TOMS Circumpolar One-Degree PAR Images  

NASA Technical Reports Server (NTRS)

The Boreal Ecosystem-Atmosphere Study (BOREAS) Remote Sensing Science (RSS)-10 team investigated the magnitude of daily, seasonal, and yearly variations of Photosynthetically Active Radiation (PAR) from ground and satellite observations. This data set contains satellite estimates of surface-incident PAR (400-700 nm, MJ/sq m) at one-degree spatial resolution. The spatial coverage is circumpolar from latitudes of 41 to 66 degrees north. The temporal coverage is from May through September for years 1979 through 1989. Eleven-year statistics are also provided: (1) mean, (2) standard deviation, and (3) coefficient of variation for 1979-89. The PAR estimates were derived from the global gridded ultraviolet reflectivity data product (average of 360, 380 nm) from the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS). Image mask data are provided for identifying the boreal forest zone, and ocean/land and snow/ice-covered areas. The data are available as binary image format data files. The PAR data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

Dye, Dennis G.; Holben, Brent; Nickeson, Jaime (Editor); Hall, Forrest G. (Editor); Smith, David E. (Technical Monitor)

2000-01-01

229

The Pars Triangularis in Dyslexia and ADHD: A Comprehensive Approach  

ERIC Educational Resources Information Center

Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one…

Kibby, Michelle Y.; Kroese, Judith M.; Krebbs, Hillery; Hill, Crystal E.; Hynd, George W.

2009-01-01

230

The pars triangularis in dyslexia and ADHD: A comprehensive approach  

Microsoft Academic Search

Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one of the purposes of this study

Michelle Y. Kibby; Judith M. Kroese; Hillery Krebbs; Crystal E. Hill; George W. Hynd

2009-01-01

231

PAR-5 is a PARty hub in the germline  

PubMed Central

As our understanding of how molecular machineries work expands, an increasing number of proteins that appear as regulators of different processes have been identified. These proteins are hubs within and among functional networks. The 14-3-3 protein family is involved in multiple cellular pathways and, therefore, influences signaling in several disease processes, from neurobiological disorders to cancer. As a consequence, 14-3-3 proteins are currently being investigated as therapeutic targets. Moreover, 14-3-3 protein levels have been associated with resistance to chemotherapies. There are seven 14-3-3 genes in humans, while Caenorhabditis elegans only possesses two, namely par-5 and ftt-2. Among the C. elegans scientific community, par-5 is mainly recognized as one of the par genes that is essential for the asymmetric first cell division in the embryo. However, a recent study from our laboratory describes roles of par-5 in germ cell proliferation and in the cellular response to DNA damage induced by genotoxic agents. In this review, we explore the broad functionality of 14-3-3 proteins in C. elegans and comment on the potential use of worms for launching a drugs/modifiers discovery platform for the therapeutic regulation of 14-3-3 function in cancer. PMID:24058859

Aristizabal-Corrales, David; Schwartz Jr, Simo; Ceron, Julian

2013-01-01

232

UN SPECTROPHOTOMTRE A DOUBLE MODULATION Par J. Y. GAY,  

E-print Network

32. UN SPECTROPHOTOM�TRE A DOUBLE MODULATION Par J. Y. GAY, Laboratoire de l'�cole Supérieure de de largeur de fente). Ces deux conditions nous ont conduit à adopter le principe de mesure décrit ci

Boyer, Edmond

233

TO ACADEMIC The PAR program provides conditional admission for  

E-print Network

-focused academic programs. The university's main campus is located in Boca Raton, conveniently located within 30PATHWAY TO ACADEMIC READINESS The PAR program provides conditional admission for academically qualified international students who need access to English language and other academic and social

Fernandez, Eduardo

234

Conception synchrone d'applications avioniques par raffinement de modles  

E-print Network

projet européen IST SAFEAIR (Advanced Design Tools for Aircraft Systems and Airborne Software - http-TIME SYSTEMS, Paris : France (2005)" #12;1 Introduction L'avionique occupe une place non négligeable dans le les fonctions sont très faiblement cou- plées (par exemple, le pilotage automatique et la navigation

Paris-Sud XI, Université de

235

Reconstruction 3D du bti partir d'une seule image par naissances et morts multiples  

E-print Network

Reconstruction 3D du bâti à partir d'une seule image par naissances et morts multiples Jean ne conserver que les plus pertinentes par un algorithme de type naissances et morts multiples. Nous plus pertinents. Ce principe est décliné par un algorithme de type naissances et morts mul- tiples

Boyer, Edmond

236

L E T T E R S Microtubules induce self-organization of polarized PAR  

E-print Network

L E T T E R S Microtubules induce self-organization of polarized PAR domains in Caenorhabditis and Geraldine Seydoux1,2 A hallmark of polarized cells is the segregation of the PAR polarity regulators, atypical protein kinase C (aPKC) and PAR-1, have been implicated in polarity maintenance1

Seydoux, Geraldine

237

SUR UN SILICATE DE CADMIUM LUMINESCENT Par A. LEVIALDI et V. LUZZATI.  

E-print Network

SUR UN SILICATE DE CADMIUM LUMINESCENT Par A. LEVIALDI et V. LUZZATI. Sommaire. - �tude de quelques propriétés d'un silicate de cadmium (1) luminescent. Leur interpré- tation par la théorie des trappes de silicate de cadmium par des radiations ultra- violettes de longueur d'onde voisine de ), = 2537 A

Boyer, Edmond

238

MESURE DU PARCOURS MOYEN DES RAYONS 03B1 DU THORIUM PAR LA MTHODE PHOTOGRAPHIQUE  

E-print Network

droite; il y a environ 26 grains par trace de thorium. Ces Trajectoires ontMESURE DU PARCOURS MOYEN DES RAYONS 03B1 DU THORIUM PAR LA M�THODE PHOTOGRAPHIQUE Par Mme HENRIETTE thorium dans l'émulsion des plaques photo- graphiques, on déduit leur parcours moyen dans l'air à150

Paris-Sud XI, Université de

239

Is assessment of anti-mullerian hormone and/or antral follicle count useful in the prediction of ovarian response in expected normal responders treated with a fixed dose of recombinant FSH and GnRH antagonists? A prospective observational study.  

PubMed

Abstract The purpose of this prospective observational study was to evaluate whether the assessment of AMH and AFC is useful in the prediction of ovarian response in expected normal responders treated with a fixed dose of recombinant FSH (rec-FSH) and GnRH antagonists. A base model including age and basal FSH as independent predictors of COCs could explain 15% of the variance observed in the number of COCs retrieved (p?=?0.002). The addition of AFC did not increase significantly the predictive ability of the above model, whereas the addition of AMH increased the performance of the base model by 13% (p?FSH, its predictive capacity for high ovarian response was statistically significant (F-test: p?=?0.001; c-statistic: 0.80, 95% CI: 0.70-0.88), but this was not the case for poor ovarian response. In conclusion, the addition of AMH, but not of AFC, to a model including female age and basal FSH, is useful in the prediction of ovarian response in expected normal responders treated with a fixed dose of recombinant FSH and GnRH antagonists. PMID:24989633

Ganidou, Maria A; Kolibianakis, Efstratios M; Venetis, Christos A; Gerou, Spiros; Makedos, Georgios A; Klearchou, Nikolaos; Tarlatzis, Basil C

2014-11-01

240

MESURE DES MOBILITS D'IONS GAZEUX PAR L'ANALYSEUR PAUL LANGEVIN Par Mme E. MONTEL,  

E-print Network

'ionisation des deux signes, en fonction de l'azimut de l'électrode collec- trice. On a tracé les courbes de donnée par la formule où 6 est l'angle de l'azimut de l'électrode collec- trice E avec celui de la fente

Boyer, Edmond

241

UN EXEMPLE DE DTERMINATION PAR APPROXIMATION DE L'METTEUR D'UN NOUVEAU SPECTRE PRODUIT PAR DES MOLCULES ORGANIQUES  

E-print Network

'un spectre d'emission, situe dans le visible entre 5 ooo et 6 50o A, observe d'abord avec le benzene, et qui contenant beaucoup de molecules d'h6lium et peu de benzene et, par consequent, avec de grandes TABLEAU I

Boyer, Edmond

242

Binding and Spreading of ParB on DNA Determine Its Biological Function in Pseudomonas aeruginosa?†  

PubMed Central

ParB protein of Pseudomonas aeruginosa belongs to a widely represented ParB family of chromosomally and plasmid-encoded partitioning type IA proteins. Ten putative parS sites are dispersed in the P. aeruginosa chromosome, with eight of them localizing in the oriC domain. After binding to parS, ParB spreads on the DNA, causing transcriptional silencing of nearby genes (A. A. Bartosik et al., J. Bacteriol. 186:6983–6998, 2004). We have studied ParB derivatives impaired in spreading either due to loss of DNA-binding ability or oligomerization. We defined specific determinants outside of the helix-turn-helix motif responsible for DNA binding. Analysis confirmed the localization of the main dimerization domain in the C terminus of ParB but also mapped another self-interactive domain in the N-terminal domain. Reverse genetics were used to introduce five parB alleles impaired in spreading into the P. aeruginosa chromosome. The single amino acid substitutions in ParB causing a defect in oligomerization but not in DNA binding caused a chromosome segregation defect, slowed the growth rate, and impaired motilities, similarly to the pleiotropic phenotype of parB-null mutants, indicating that the ability to spread is vital for ParB function in the cell. The toxicity of ParB overproduction in Pseudomonas spp. is not due to the spreading since several ParB derivatives defective in oligomerization were still toxic for P. aeruginosa when provided in excess. PMID:21531806

Kusiak, Magdalena; Gapczynska, Anna; Plochocka, Danuta; Thomas, Christopher M.; Jagura-Burdzy, Grazyna

2011-01-01

243

The physical association of the P2Y12 receptor with PAR4 regulates arrestin-mediated Akt activation.  

PubMed

It is now well accepted that protease activated receptor (PAR) 1 and PAR4 have differential roles in platelet activation. PAR4, a low-affinity thrombin receptor in human platelets, participates in sustained platelet activation in a P2Y12-dependent manner; however, the mechanisms are not defined. Our previous studies demonstrated that thrombin induces the association of PAR4 with P2Y12, together with arrestin recruitment to the complex. Here we show that PAR4 and P2Y12 directly interact to coregulate Akt signaling after PAR4 activation. We observed direct and specific interaction of P2Y12 with PAR4 but not PAR1 by bioluminescent resonance energy transfer when the receptors were coexpressed in human embryonic kidney 293T cells. PAR4-P2Y12 dimerization was promoted by PAR4-AP and inhibited by P2Y12 antagonist. By using sequence comparison of the transmembrane domains of PAR1 and PAR4, we designed a mutant form of PAR4, "PAR4SFT," by replacing LGL194-196 at the base of transmembrane domain 4 with the corresponding aligned PAR1 residues SFT 220-222. PAR4SFT supported only 8.74% of PAR4-P2Y12 interaction, abolishing P2Y12-dependent arrestin recruitment to PAR4 and Akt activation. Nonetheless, PAR4SFT still supported homodimerization with PAR4. PAR4SFT failed to induce a calcium flux when expressed independently; however, coexpression of increasing concentrations of PAR4SFT, together with PAR4 potentiated PAR4-mediated calcium flux, suggested that PAR4 act as homodimers to signal to Gq-coupled calcium responses. In conclusion, PAR4 LGL (194-196) governs agonist-dependent association of PAR4 with P2Y12 and contributes to Gq-coupled calcium responses. PAR4-P2Y12 association supports arrestin-mediated sustained signaling to Akt. Hence, PAR4-P2Y12 dimerization is likely to be important for the PAR4-P2Y12 dependent stabilization of platelet thrombi. PMID:24723492

Khan, Aasma; Li, Dongjun; Ibrahim, Salam; Smyth, Emer; Woulfe, Donna S

2014-07-01

244

Sur l'actinium et l'ionium Par B. SZILARD  

E-print Network

séparé le plomb' par l'hydrogène sul- furé, j'ai précipité les phosphates5 par l'hydrate d phosphates entraînaient la majeure partie de l'activité, quoique la liqueur restât, elle aussi, active. Elle qui se formaient dans le produit a été contrôlée par l'absorption qu'ils subissaient par des lames d'aluminium

Paris-Sud XI, Université de

245

ParCAT: A Parallel Climate Analysis Toolkit  

NASA Astrophysics Data System (ADS)

Climate science has employed increasingly complex models and simulations to analyze the past and predict the future of our climate. The size and dimensionality of climate simulation data has been growing with the complexity of the models. This growth in data is creating a widening gap between the data being produced and the tools necessary to analyze large, high dimensional data sets. With single run data sets increasing into 10's, 100's and even 1000's of gigabytes, parallel computing tools are becoming a necessity in order to analyze and compare climate simulation data. The Parallel Climate Analysis Toolkit (ParCAT) provides basic tools that efficiently use parallel computing techniques to narrow the gap between data set size and analysis tools. ParCAT was created as a collaborative effort between climate scientists and computer scientists in order to provide efficient parallel implementations of the computing tools that are of use to climate scientists. Some of the basic functionalities included in the toolkit are the ability to compute spatio-temporal means and variances, differences between two runs and histograms of the values in a data set. ParCAT is designed to facilitate the "heavy lifting" that is required for large, multidimensional data sets. The toolkit does not focus on performing the final visualizations and presentation of results but rather, reducing large data sets to smaller, more manageable summaries. The output from ParCAT is provided in commonly used file formats (NetCDF, CSV, ASCII) to allow for simple integration with other tools. The toolkit is currently implemented as a command line utility, but will likely also provide a C library for developers interested in tighter software integration. Elements of the toolkit are already being incorporated into projects such as UV-CDAT and CMDX. There is also an effort underway to implement portions of the CCSM Land Model Diagnostics package using ParCAT in conjunction with Python and gnuplot. ParCAT is implemented in C to provide efficient file IO. The file IO operations in the toolkit use the parallel-netcdf library; this enables the code to use the parallel IO capabilities of modern HPC systems. Analysis that currently requires an estimated 12+ hours with the traditional CCSM Land Model Diagnostics Package can now be performed in as little as 30 minutes on a single desktop workstation and a few minutes for relatively small jobs completed on modern HPC systems such as ORNL's Jaguar.

Haugen, B.; Smith, B.; Steed, C.; Ricciuto, D. M.; Thornton, P. E.; Shipman, G.

2012-12-01

246

Mcanismes molculaires d'activation et d'inhibition de la sucrase intestinale par les cations alcalins et par les protons, par Monique VASSEUR, G. Van MELLE et F. ALVARADO.Monique VASSEUR, G. Van MELLE F. ALVARADO  

E-print Network

alcalins et par les protons, par Monique VASSEUR, G. Van MELLE et F. ALVARADO.Monique VASSEUR, G. Van MELLE F. ALVARADO C. N. R. S. Centre de Recherches Nutrition, 9, rue J. Hetzel 92190 Meudon Bel plusieurs sites inhibiteurs de fixations des métaux. (1) Vasseur M., Tellier C., Alvarado F., 1982. Sodium

Paris-Sud XI, Université de

247

Expression of Partitioning Defective 3 (Par-3) for Predicting Extrahepatic Metastasis and Survival with Hepatocellular Carcinoma  

PubMed Central

Partitioning defective 3 (Par-3), a crucial component of partitioning-defective complex proteins, controls cell polarity and contributes to cell migration and cancer cell epithelial-to-mesenchymal transition. However, the clinical relevance of Par-3 in tumor progression and metastasis has not been well elucidated. In this study, we investigated the impact and association of Par-3 expression and clinical outcomes with hepatocellular carcinoma (HCC). We first confirmed that Par-3 was abundantly expressed in HCC cell lines by Western blot analysis. We used immunohistochemistry to analyze the association of Par-3 expression and clinicopathological characteristics in primary and subsequent metastatic tumors of patients with HCC. Par-3 was overexpressed in 47 of 111 (42.3%) primary tumors. Increased expression of Par-3 in primary tumors predicted an increased five-year cumulative incidence of extrahepatic metastasis. In addition, multivariate analysis revealed that Par-3 overexpression was an independent risk factor of extrahepatic metastasis. Increased Par-3 expression in primary tumors was associated with poor five-year overall survival rates and was an independent prognostic factor on Cox regression analysis. In conclusion, we show for the first time that increased Par-3 expression is associated with distant metastasis and poor survival rates in patients with HCC. Par-3 may be a novel prognostic biomarker and therapeutic target for HCC. PMID:23322019

Jan, Yee-Jee; Ko, Bor-Sheng; Liu, Tzu-An; Wu, Yao-Ming; Liang, Shu-Man; Chen, Shyh-Chang; Wang, John; Liou, Jun-Yang

2013-01-01

248

Proteinase-Activated Receptor 1 (PAR1) regulates leukemic stem cell functions.  

PubMed

External signals that are mediated by specific receptors determine stem cell fate. The thrombin receptor PAR1 plays an important role in haemostasis, thrombosis and vascular biology, but also in tumor biology and angiogenesis. Its expression and function in hematopoietic stem cells is largely unknown. Here, we analyzed expression and function of PAR1 in primary hematopoietic cells and their leukemic counterparts. AML patients' blast cells expressed much lower levels of PAR1 mRNA and protein than CD34+ progenitor cells. Constitutive Par1-deficiency in adult mice did not affect engraftment or stem cell potential of hematopoietic cells. To model an AML with Par1-deficiency, we retrovirally introduced the oncogene MLL-AF9 in wild type and Par1-/- hematopoietic progenitor cells. Par1-deficiency did not alter initial leukemia development. However, the loss of Par1 enhanced leukemic stem cell function in vitro and in vivo. Re-expression of PAR1 in Par1-/- leukemic stem cells delayed leukemogenesis in vivo. These data indicate that Par1 contributes to leukemic stem cell maintenance. PMID:24740120

Bäumer, Nicole; Krause, Annika; Köhler, Gabriele; Lettermann, Stephanie; Evers, Georg; Hascher, Antje; Bäumer, Sebastian; Berdel, Wolfgang E; Müller-Tidow, Carsten; Tickenbrock, Lara

2014-01-01

249

ParABS Systems of the Four Replicons of Burkholderia cenocepacia: New Chromosome Centromeres Confer Partition Specificity†  

PubMed Central

Most bacterial chromosomes carry an analogue of the parABS systems that govern plasmid partition, but their role in chromosome partition is ambiguous. parABS systems might be particularly important for orderly segregation of multipartite genomes, where their role may thus be easier to evaluate. We have characterized parABS systems in Burkholderia cenocepacia, whose genome comprises three chromosomes and one low-copy-number plasmid. A single parAB locus and a set of ParB-binding (parS) centromere sites are located near the origin of each replicon. ParA and ParB of the longest chromosome are phylogenetically similar to analogues in other multichromosome and monochromosome bacteria but are distinct from those of smaller chromosomes. The latter form subgroups that correspond to the taxa of their hosts, indicating evolution from plasmids. The parS sites on the smaller chromosomes and the plasmid are similar to the “universal” parS of the main chromosome but with a sequence specific to their replicon. In an Escherichia coli plasmid stabilization test, each parAB exhibits partition activity only with the parS of its own replicon. Hence, parABS function is based on the independent partition of individual chromosomes rather than on a single communal system or network of interacting systems. Stabilization by the smaller chromosome and plasmid systems was enhanced by mutation of parS sites and a promoter internal to their parAB operons, suggesting autoregulatory mechanisms. The small chromosome ParBs were found to silence transcription, a property relevant to autoregulation. PMID:16452432

Dubarry, Nelly; Pasta, Franck; Lane, David

2006-01-01

250

Is PAR a Good Investment? Understanding the Costs and Benefits of Teacher Peer Assistance and Review Programs  

ERIC Educational Resources Information Center

Peer Assistance and Review (PAR) is a local labor-management initiative designed to improve teacher quality. In PAR, expert "consulting teachers" mentor, support, and evaluate novice and underperforming veteran teachers. Evaluations under PAR can lead to dismissals. The authors examine the costs and benefits of PAR, both financial and…

Papay, John P.; Johnson, Susan Moore

2012-01-01

251

LES MICROBES ET LE LAIT, par le Dl' VIOLLE.  

E-print Network

LES MICROBES ET LE LAIT, par le Dl' VIOLLE. d'e l'Institut Pasteur. Le lait est, à lui seul, la,originellement.snin, vierge de tout microbe et de tout corps toxique. Mai,s s'il parvient à maintenir la vie de l'adulte, à milieu qui contient les trois grands principes 'alimentaires, des sels minéraux et de l'eau, les microbes

Paris-Sud XI, Université de

252

Classification de courriers lectroniques Une approche par apprentissage  

E-print Network

Classification de courriers électroniques Une approche par apprentissage basée sur des modèles courriers électroniques proposent des systèmes de sélection de courriers. Cette sélection est une indiquer au logiciel. La présence ou l'absence de ces mots-clés en fonction des divers champs du courrier

Paris-Sud XI, Université de

253

Au XIXe siècle : industrialisation linéaire ou industrialisation par bonds ?  

Microsoft Academic Search

[fre] Au XIXe siècle : industrialisation lineaire ou industrialisation par bonds ?. . Depuis 1945, beaucoup d'historiens économistes français, sous l'impulsion d'Ernest Labrousse, ont approfondi l'analyse des structures sociales et des mouvements conjoncturels. Mais Walt W. Rostow a présenté une analyse de la croissance selon laquelle l'industrialisation aurait été assurée grâce à de brèves périodes de take-off. Les travaux de

Marcel Gillet

1972-01-01

254

Bourses d'tudes aux 5 000 $ US par semestre  

E-print Network

Bourses d'études aux �tats-Unis 5 000 $ US par semestre Allocation pour l'assurance médicale de 1er cycle à temps plein Le programme de bourses Killam www.killamfellowships.com Geneviève Boutin-Maison Boursier Killam 2013-2014 Université d'Ottawa #12;Un coup d'oeil sur la bourse LE PROGRAMME DE BOURSES

Petriu, Emil M.

255

Electrocardiogram (ECG) Biometric Authentication Using Pulse Active Ratio (PAR)  

Microsoft Academic Search

Biometric authentication is a one-to-one verification process.A successful biometric system must be capable of avoiding a fraudulent claim while at the same time ensuring the privacy of individuals. This paper presents a novel framework for using the electrocardiogram (ECG) as a biometric system for human au- thentication. A new feature extraction technique known as pulse active ratio (PAR) is derived

Sairul I. Safie; John J. Soraghan; Lykourgos Petropoulakis

2011-01-01

256

PROPRITS LECTRIQUES ET OPTIQUES DU BORE Par J. LAGRENAUDIE.  

E-print Network

PROPRI�T�S �LECTRIQUES ET OPTIQUES DU BORE Par J. LAGRENAUDIE. Laboratoire de Physique de l'E. N. S. Sommaire. 2014 La conductibilité du bore à basse température dénote des énergies d'activation d'impu- reté'élément Bore, au laboratoire de Physique de l'E. N. S. : io Conductibilité à différentes températures; 20

Paris-Sud XI, Université de

257

TUDE DES PROPRITS DU BORE Par J. LAGRENAUDIE.  

E-print Network

14. �TUDE DES PROPRI�T�S DU BORE Par J. LAGRENAUDIE. Laboratoire de Physique E. N. S. Sommaire. 2014 Le bore présente, selon des mesures poussées jusque vers 700° C,une énergie intrin- sèque d, JANVIER 1953, Rappelons que les trois catégories d'échantillons étudiés se composent de : A. Bore obtenu

Paris-Sud XI, Université de

258

Valid par CA du 31 janvier 2012 COMMISSIONS CULTURE  

E-print Network

Validé par CA du 31 janvier 2012 1 COMMISSIONS CULTURE Fonctionnement des commissions culture et actions dans le domaine de la culture. Afin de mener une politique culturelle cohérente avec les différents acteurs bourguignons de la culture, l'université de Bourgogne a décidé d'appuyer sa stratégie

Herrmann, Samuel

259

Cheminement par trimestre Le Baccalaurat en mathmatiques et informatique  

E-print Network

/ majeure-en-informatique/structure-du-programme/. Ce programme totalise 49 crédits obligatoires dont 24 enCheminement par trimestre Le Baccalauréat en mathématiques et informatique Le baccalauréat Le baccalauréat en mathématiques et informatique assure une formation solide en mathéma- tiques tout en permettant

Montréal, Université de

260

Cheminement par trimestre -Baccalaurat en informatique La passerelle DEC SIM  

E-print Network

référer à la structure du programme disponible sur le site des admissions à l'adresse : http://admission.umontreal.ca/programmes/majeure-en-informatiqueCheminement par trimestre - Baccalauréat en informatique La passerelle DEC SIM Le baccalauréat en informatique Le baccalauréat en informatique mise sur les aspects fondamentaux de l'informatique, favorisant l

Montréal, Université de

261

The Epic of Pabuji ki par in Performance  

E-print Network

for online viewing and download. Dr Mark Turin World Oral Literature Project University of Cambridge October 2010 The epic of Pabuji ki par in performance?1 moving lips. Who was singing? Finally, when the husband responded with an audibly enthusiastic... . ‘Cultural’ scenes including exotic animals and bovines, humans and the more familiar hunting encounters have been found on the walls of rock caves dating to the Paleolithic and Mesolithic periods. 18?I am grateful to my colleague Vimal Gopa of Jaisalmer...

Wickett, Elizabeth

2010-10-19

262

APPLICATION DES PALIERS A GAZ AUX GYROSCOPES Par G. GOBERT,  

E-print Network

43 APPLICATION DES PALIERS A GAZ AUX GYROSCOPES Par G. GOBERT, Centre d'�tudes Nucléaires de Saclay gyroscope dont le rotor de 4 cm de diamètre pesant plusieurs centaines de grammes tourne à une vitesse to the construction of a gyroscope. The rotor is 4 cm in diameter and runs at 180 000 r. p. m. Its weight is 500 g. LE

Paris-Sud XI, Université de

263

THORIE DES SAUTS QUANTIQUES par M. J. ULLMO.  

E-print Network

fréquences données par l'équation de Schrodinger, qui est re- trouvée à partir des conceptions précédentes» apparaissent. (Le succès de l'interprétation statistique de l'équation de Schrodinger est attribuée aux. Lorsque M. Louis de Broglie a introduit ses « ondes de phasc » , il les concevrait comme un phénomène

Paris-Sud XI, Université de

264

The Par-4-GRP78 TRAIL, more twists and turns.  

PubMed

GRP78, also referred to as BiP, is an essential molecular chaperone and a master regulator of the unfolded protein response. Traditionally, GRP78 is regarded as localized in the lumen of the endoplasmic reticulum (ER). However, recent findings revealed that a subfraction of GRP78 can localize to the surface of specific cell types. Furthermore, preferential expression of GRP78 on the surface of tumor cells but not in normal organs suggests that surface GRP78 can serve both as a target as well as mediator for cancer-specific therapy. Recent reports further established that GRP78 forms complexes with specific proteins on the cell surface and plays an important role in signaling, impacting cell survival and proliferation. Burikhanov et al. (Cell 2009, 138:377) reported that Par-4, generally regarded as a cytosolic and nuclear protein that promotes cell death via the mitochondrial cell death pathway, is spontaneously secreted by normal and cancer cells and this process is enhanced by ER stress or with addition of TRAIL. It is proposed that ER stress, induced by extracellular insults such as TRAIL, causes translocation of the Par-4-GRP78 complex from the ER to the plasma membrane, and through a positive feedback loop, extracellular Par-4 binds to cell surface GRP78 and activates the extrinsic apoptotic pathway. In this journal club, we discuss some open questions and how these new findings integrate with current understanding of GRP78 function in vivo. PMID:19823030

Lee, Amy S

2009-11-01

265

Transcriptional profiling of ParA and ParB mutants in actively dividing cells of an opportunistic human pathogen Pseudomonas aeruginosa.  

PubMed

Accurate chromosome segregation to progeny cells is a fundamental process ensuring proper inheritance of genetic material. In bacteria with simple cell cycle, chromosome segregation follows replication initiation since duplicated oriC domains start segregating to opposite halves of the cell soon after they are made. ParA and ParB proteins together with specific DNA sequences are parts of the segregation machinery. ParA and ParB proteins in Pseudomonas aeruginosa are important for optimal growth, nucleoid segregation, cell division and motility. Comparative transcriptome analysis of parA null and parB null mutants versus parental P. aeruginosa PAO1161 strain demonstrated global changes in gene expression pattern in logarithmically growing planktonic cultures. The set of genes similarly affected in both mutant strains is designated Par regulon and comprises 536 genes. The Par regulon includes genes controlled by two sigma factors (RpoN and PvdS) as well as known and putative transcriptional regulators. In the absence of Par proteins, a large number of genes from RpoS regulon is induced, reflecting the need for slowing down the cell growth rate and decelerating the metabolic processes. Changes in the expression profiles of genes involved in c-di-GMP turnover point out the role of this effector in such signal transmission. Microarray data for chosen genes were confirmed by RT-qPCR analysis. The promoter regions of selected genes were cloned upstream of the promoter-less lacZ gene and analyzed in the heterologous host E. coli?lac. Regulation by ParA and ParB of P. aeruginosa was confirmed for some of the tested promoters. Our data demonstrate that ParA and ParB besides their role in accurate chromosome segregation may act as modulators of genes expression. Directly or indirectly, Par proteins are part of the wider regulatory network in P. aeruginosa linking the process of chromosome segregation with the cell growth, division and motility. PMID:24498062

Bartosik, Aneta A; Glabski, Krzysztof; Jecz, Paulina; Mikulska, Sylwia; Fogtman, Anna; Koblowska, Marta; Jagura-Burdzy, Grazyna

2014-01-01

266

A model for the condensation of the bacterial chromosome by the partitioning protein ParB  

NASA Astrophysics Data System (ADS)

The molecular machinery responsible for faithful segregation of the chromosome in bacteria such as Caulobacter crescentus and Bacillus subtilis includes the ParABS a.k.a. Spo0J/Soj partitioning system. In Caulobacter, prior to division, hundreds of ParB proteins bind to the DNA near the origin of replication, and localize to one pole of the cell. Subsequently, the ParB-DNA complex is translocated to the far pole by the binding and retraction of the ParA spindle-like apparatus. Remarkably, the localization of ParB proteins to specific regions of the chromosome appears to be controlled by only a few centromeric parS binding sites. Although lateral interactions between DNA-bound ParB are likely to be important for their localization, the long-range order of ParB domains on the chromosome appears to be inconsistent with a picture in which protein-protein interactions are limited to neighboring DNA-bound proteins. We developed a coarse-grained Brownian dynamics model that allows for lateral and 3D protein-protein interactions among bound ParB proteins. Our model shows how such interactions can condense and organize the DNA spatially, and can control the localization and the long-range order of the DNA-bound proteins.

Broedersz, Chase; Wingreen, Ned

2013-03-01

267

PAR-1 contributes to the innate immune response during viral infection  

PubMed Central

Coagulation is a host defense system that limits the spread of pathogens. Coagulation proteases, such as thrombin, also activate cells by cleaving PARs. In this study, we analyzed the role of PAR-1 in coxsackievirus B3–induced (CVB3-induced) myocarditis and influenza A infection. CVB3-infected Par1–/– mice expressed reduced levels of IFN-? and CXCL10 during the early phase of infection compared with Par1+/+ mice that resulted in higher viral loads and cardiac injury at day 8 after infection. Inhibition of either tissue factor or thrombin in WT mice also significantly increased CVB3 levels in the heart and cardiac injury compared with controls. BM transplantation experiments demonstrated that PAR-1 in nonhematopoietic cells protected mice from CVB3 infection. Transgenic mice overexpressing PAR-1 in cardiomyocytes had reduced CVB3-induced myocarditis. We found that cooperative signaling between PAR-1 and TLR3 in mouse cardiac fibroblasts enhanced activation of p38 and induction of IFN-? and CXCL10 expression. Par1–/– mice also had decreased CXCL10 expression and increased viral levels in the lung after influenza A infection compared with Par1+/+ mice. Our results indicate that the tissue factor/thrombin/PAR-1 pathway enhances IFN-? expression and contributes to the innate immune response during single-stranded RNA viral infection. PMID:23391721

Antoniak, Silvio; Owens, A. Phillip; Baunacke, Martin; Williams, Julie C.; Lee, Rebecca D.; Weithauser, Alice; Sheridan, Patricia A.; Malz, Ronny; Luyendyk, James P.; Esserman, Denise A.; Trejo, JoAnn; Kirchhofer, Daniel; Blaxall, Burns C.; Pawlinski, Rafal; Beck, Melinda A.; Rauch, Ursula; Mackman, Nigel

2013-01-01

268

MISSION DE POSITONS PAR LES SOURCES RADIOACTIVES Par A. I. ALICHANOW, A. I. ALICHANIAN et M. S. KOSODAEW.  

E-print Network

de préparer que des sources très faibles. Le Thorium (C + C") sa tioe lai partiellement à la seconde'émission intense des positons par le dépôt actif du Thorium est déjà connue. J. Chadwick, P. Blackett et G. Occhialini ont observé à la chambre de Wilson 24 positons pour 2000 particules fi, soit environ, 1 pour 100

Boyer, Edmond

269

TUDE DU COBALT BOMBARD PAR DES LECTRONS A 20 K Par G. SULPICE, C. MINIER, P. MOSER et H. BILGER,  

E-print Network

les défauts créés sont essentiellement des paires de Frenkel proches qui se guérissent en dessous de 65 °K. Abstract. 2014 Electrical resistivity measurements seem to indicate that the point defects si nous suppo- sons qu'un meme bombardement, par des electrons de 1,4 MeV, cree la meme concentration

Paris-Sud XI, Université de

270

Proteinases and signalling: pathophysiological and therapeutic implications via PARs and more  

PubMed Central

Proteinases like thrombin, trypsin and tissue kallikreins are now known to regulate cell signaling by cleaving and activating a novel family of G-protein-coupled proteinase-activated receptors (PARs 1–4) via exposure of a tethered receptor-triggering ligand. On their own, short synthetic PAR-selective PAR-activating peptides (PAR-APs) mimicking the tethered ligand sequences can activate PARs 1, 2 and 4 and cause physiological responses both in vitro and in vivo. Using the PAR-APs as sentinel probes in vivo, it has been found that PAR activation can affect the vascular, renal, respiratory, gastrointestinal, musculoskeletal and nervous systems (both central and peripheral nervous system) and can promote cancer metastasis and invasion. In general, responses triggered by PARs 1, 2 and 4 are in keeping with an innate immune inflammatory response, ranging from vasodilatation to intestinal inflammation, increased cytokine production and increased or decreased nociception. Further, PARs have been implicated in a number of disease states, including cancer and inflammation of the cardiovascular, respiratory, musculoskeletal, gastrointestinal and nervous systems. In addition to activating PARs, proteinases can cause hormone-like effects by other signalling mechanisms, like growth factor receptor activation, that may be as important as the activation of PARs. We, therefore, propose that the PARs themselves, their activating serine proteinases and their associated signalling pathways can be considered as attractive targets for therapeutic drug development. Thus, proteinases in general must now be considered as ‘hormone-like' messengers that can signal either via PARs or other mechanisms. PMID:18059329

Ramachandran, R; Hollenberg, M D

2008-01-01

271

Par-4-mediated recruitment of Amida to the actin cytoskeleton leads to the induction of apoptosis  

SciTech Connect

Par-4 (prostate apoptosis response-4) sensitizes cells to apoptotic stimuli, but the exact mechanisms are still poorly understood. Using Par-4 as bait in a yeast two-hybrid screen, we identified Amida as a novel interaction partner, a ubiquitously expressed protein which has been suggested to be involved in apoptotic processes. Complex formation of Par-4 and Amida occurs in vitro and in vivo and is mediated via the C-termini of both proteins, involving the leucine zipper of Par-4. Amida resides mainly in the nucleus but displays nucleo-cytoplasmic shuttling in heterokaryons. Upon coexpression with Par-4 in REF52.2 cells, Amida translocates to the cytoplasm and is recruited to actin filaments by Par-4, resulting in enhanced induction of apoptosis. The synergistic effect of Amida/Par-4 complexes on the induction of apoptosis is abrogated when either Amida/Par-4 complex formation or association of these complexes with the actin cytoskeleton is impaired, indicating that the Par-4-mediated relocation of Amida to the actin cytoskeleton is crucial for the pro-apoptotic function of Par-4/Amida complexes in REF52.2 cells. The latter results in enhanced phosphorylation of the regulatory light chain of myosin II (MLC) as has previously been shown for Par-4-mediated recruitment of DAP-like kinase (Dlk), suggesting that the recruitment of nuclear proteins involved in the regulation of apoptotic processes to the actin filament system by Par-4 represents a potent mechanism how Par-4 can trigger apoptosis.

Boosen, Meike [Institute of Genetics, University of Bonn, Roemerstr. 164, D-53117 Bonn (Germany); Vetterkind, Susanne [Institute of Genetics, University of Bonn, Roemerstr. 164, D-53117 Bonn (Germany); Koplin, Ansgar [Institute of Genetics, University of Bonn, Roemerstr. 164, D-53117 Bonn (Germany); Illenberger, Susanne [Cell Biology, Zoological Institute, Technical University of Braunschweig, D-38092 Braunschweig (Germany); Preuss, Ute [Institute of Genetics, University of Bonn, Roemerstr. 164, D-53117 Bonn (Germany)]. E-mail: u.preuss@uni-bonn.de

2005-12-10

272

LH and FSH concentration and follicular development in Nellore heifers submitted to fixed-time artificial insemination protocols with different progesterone concentrations.  

PubMed

Nine heifers were pre-synchronized (PGF2?, 12 days) and assigned into three groups with 6 repetitions each: (1) CL (?8 days old, n=13); (2) DIB+CL (n=18); (3) DIB+EB (150 ?g of PGF2? and 2mg estradiol benzoate, n=18). After progesterone (P4) device removal (8 days) and/or final PGF2?, heifers were injected with either GnRH or EB in a 3×2 factorial totalling 49 observations (5 were excluded). The blood sampling schedule: every 12 h during P4 period; for LH pulse frequency on Days 3-5, every 15 min for 6 h during P4 period; after P4 removal and EB treatment, samples were collected every 3 h for 24 h or after GnRH every 1 h for 10 h. Ovarian follicle number and diameter were evaluated by ultrasonography every 12 h until the last blood sample and then 24 h and 48 h later. After device insertion (12 h), the DIB+CL group had a lesser LH concentration than the DIB+EB group. After 36 h, all DIB+CL-treated heifers had less LH than CL-heifers, and after 60 h, the DIB+EB group had less LH than the CL-group. Considering all P4 groups combined, LH peak amplitude was greater after GnRH compared to EB treatment but total area of LH peak amplitude and time to first peak was less. The CL-group had fewer follicles and a greater largest follicle diameter than DIB+CL and DIB+EB groups. When treated with EB, the DIB+CL group had a lesser ovulation rate at 24 h than the CL- and DIB+EB-groups. Fixed time artificial insemination (FTAI) protocols promoted a pre-ovulatory LH peak, independent of previous exposure to the DIB coupled with a CL or not. The progesterone excess interfered with FSH and LH secretion, follicular development and ovulation within 24 h. PMID:21820254

Cipriano, R S; Carvalho, B A; Marangoni, N R; Nogueira, G P

2011-08-01

273

Effect of mouse epidermal growth factor on plasma concentrations of FSH, LH and progesterone and on oestrus, ovulation and ovulation rate in merino ewes.  

PubMed

The 24 h i.v. infusion of Merino ewes with 60 or 100 microgram mouse epidermal growth factor (EGF)/kg body weight on Days 4, 9 or 14 of the oestrous cycle decreased the strength of wool attachment and caused marked changes in subsequent reproductive performance. In ovaries removed 2 days after EGF treatment all follicles greater than or equal to 0.6 mm diameter were atretic. After 7 days either a normal pattern of atresia or no atresia was evident while after 12 days the pattern of follicular atresia was similar to that in controls. Irrespective of stage of cycle EGF caused dose-dependent increases in plasma FSH concentrations that persisted for up to 14 days. Changes in plasma LH concentrations were generally similar after infusion on Days 4 and 14, but were smaller and shorter-lived after infusion on Day 9. Irrespective of dose, the infusion of EGF on Days 4 and 14 caused immediate luteolysis then the formation of a luteinized follicle in many ewes. Most ewes treated on Day 4 returned to oestrus between Days 17 and 21 with the same ovulation rate (1.3) as the controls. Of those infused on Day 14 oestrus occurred about a cycle length later than expected and their ovulation rate then (1.9) was also similar to that of the controls (1.7). Luteal function was not affected in ewes infused on Day 9, and most returned to oestrus between Days 17 and 20 with an ovulation rate of 3.2. Fertile rams were not placed with the ewes until after the differences in ovulation rate had been observed. Mating occurred generally 2-4 weeks after treatment, and there were no differences between EGF-treated and control ewes in fertility or fecundity. The results are interpreted as indicating that mouse EGF induces ovarian follicular atresia but has differential effects on luteal function according to the stage of the oestrous cycle at which it is given. As a consequence of these two effects, which lead to differential changes in gonadotrophin secretion, ovarian function may be temporarily impaired, little affected or improved. PMID:3116227

Radford, H M; Panaretto, B A; Avenell, J A; Turnbull, K E

1987-07-01

274

Estimating Photosynthetically Available Radiation (PAR) at the Earth's surface from satellite observations  

NASA Technical Reports Server (NTRS)

Current satellite algorithms to estimate photosynthetically available radiation (PAR) at the earth' s surface are reviewed. PAR is deduced either from an insolation estimate or obtained directly from top-of-atmosphere solar radiances. The characteristics of both approaches are contrasted and typical results are presented. The inaccuracies reported, about 10 percent and 6 percent on daily and monthly time scales, respectively, are useful to model oceanic and terrestrial primary productivity. At those time scales variability due to clouds in the ratio of PAR and insolation is reduced, making it possible to deduce PAR directly from insolation climatologies (satellite or other) that are currently available or being produced. Improvements, however, are needed in conditions of broken cloudiness and over ice/snow. If not addressed properly, calibration/validation issues may prevent quantitative use of the PAR estimates in studies of climatic change. The prospects are good for an accurate, long-term climatology of PAR over the globe.

Frouin, Robert

1993-01-01

275

Allocation de crneaux de dcollage sans conflit en programmation par contraintes  

E-print Network

Allocation de créneaux de décollage sans conflit en programmation par contraintes Cyril Allignol1@recherche.enac.fr Mots-Clés : Créneau de décollage, Résolution de conflit, Programmation par contraintes 1 Introduction proposons de résoudre directement les conflits potentiels entre les différents vols par des modifications

Paris-Sud XI, Université de

276

uPAR-Induced Cell Adhesion and Migration: Vitronectin Provides the Key  

Microsoft Academic Search

Expression of the membrane receptor uPAR induces profound changes in cell morphology and migration, and its expression correlates with the malignant phenotype of cancers. To identify the molecular interactions essential for uPAR function in these processes, we carried out a complete functional alanine scan of uPAR in HEK293 cells. Of the 255 mutant receptors characterized, 34 failed to induce changes

Chris D. Madsen; Gian Maria Sarra Ferraris; Annapaola Andolfo; Orla Cunningham; Nicolai Sidenius

2007-01-01

277

Cathepsin S Causes Inflammatory Pain via Biased Agonism of PAR2 and TRPV4.  

PubMed

Serine proteases such as trypsin and mast cell tryptase cleave protease-activated receptor-2 (PAR2) at R(36)?S(37) and reveal a tethered ligand that excites nociceptors, causing neurogenic inflammation and pain. Whether proteases that cleave PAR2 at distinct sites are biased agonists that also induce inflammation and pain is unexplored. Cathepsin S (Cat-S) is a lysosomal cysteine protease of antigen-presenting cells that is secreted during inflammation and which retains activity at extracellular pH. We observed that Cat-S cleaved PAR2 at E(56)?T(57), which removed the canonical tethered ligand and prevented trypsin activation. In HEK and KNRK cell lines and in nociceptive neurons of mouse dorsal root ganglia, Cat-S and a decapeptide mimicking the Cat-S-revealed tethered ligand-stimulated PAR2 coupling to G?s and formation of cAMP. In contrast to trypsin, Cat-S did not mobilize intracellular Ca(2+), activate ERK1/2, recruit ?-arrestins, or induce PAR2 endocytosis. Cat-S caused PAR2-dependent activation of transient receptor potential vanilloid 4 (TRPV4) in Xenopus laevis oocytes, HEK cells and nociceptive neurons, and stimulated neuronal hyperexcitability by adenylyl cyclase and protein kinase A-dependent mechanisms. Intraplantar injection of Cat-S caused inflammation and hyperalgesia in mice that was attenuated by PAR2 or TRPV4 deletion and adenylyl cyclase inhibition. Cat-S and PAR2 antagonists suppressed formalin-induced inflammation and pain, which implicates endogenous Cat-S and PAR2 in inflammatory pain. Our results identify Cat-S as a biased agonist of PAR2 that causes PAR2- and TRPV4-dependent inflammation and pain. They expand the role of PAR2 as a mediator of protease-driven inflammatory pain. PMID:25118282

Zhao, Peishen; Lieu, TinaMarie; Barlow, Nicholas; Metcalf, Matthew; Veldhuis, Nicholas A; Jensen, Dane D; Kocan, Martina; Sostegni, Silvia; Haerteis, Silke; Baraznenok, Vera; Henderson, Ian; Lindström, Erik; Guerrero-Alba, Raquel; Valdez-Morales, Eduardo E; Liedtke, Wolfgang; McIntyre, Peter; Vanner, Stephen J; Korbmacher, Christoph; Bunnett, Nigel W

2014-09-26

278

A low-complexity PAR-reduction method for DMT-VDSL  

Microsoft Academic Search

Abstract DMT-VDSL signals have a high peak-to-average power ratio (PAR). In the transmitters, the PAR governs the necessary resolution of the digital-to-analog converter (DAC) and is an important factor for the power consumption of the line-driver. Aiming at implementation in a specific system, we propose a low complexity PAR-reduction method based on the iterative algorithm derived in [5, 20, 24,

Per Ola B Orjesson; Hans G. Feichtinger; Niklas Grip; Mikael Isaksson; Norbert Kaiblinger; Per Odling; Lars-erik Persson

279

Pars intermedia of the pituitary gland and integumentary colour changes in the garden lizard Calotes versicolor  

Microsoft Academic Search

1.The effect of light and of colour of the background on the secretory activity of the pars intermedia of the garden lizard has been investigated.2.Absence of light, as well as black illuminated background, produces increased acticity of the pars intermedia, proportional to the duration of the experiment.3.Pale illuminated background has no effect on the secretory activity of the pars intermedia.4.The

Shanta Nayar; K. R. Pandalai

1963-01-01

280

The Urokinase Receptor (uPAR) Facilitates Clearance of Borrelia burgdorferi  

Microsoft Academic Search

The causative agent of Lyme borreliosis, the spirochete Borrelia burgdorferi, has been shown to induce expression of the urokinase receptor (uPAR); however, the role of uPAR in the immune response against Borrelia has never been investigated. uPAR not only acts as a proteinase receptor, but can also, dependently or independently of ligation to uPA, directly affect leukocyte function. We here

Joppe W. R. Hovius; Maarten F. Bijlsma; Gerritje J. W. van der Windt; W. Joost Wiersinga; Bastiaan J. D. Boukens; Jeroen Coumou; Anneke Oei; Regina de Beer; Alex F. de Vos; Cornelis van t Veer; Alje P. van Dam; Penghua Wang; Erol Fikrig; Marcel M. Levi; Joris J. T. H. Roelofs; Tom van der Poll

2009-01-01

281

Inactivation of the Candidate Tumor Suppressor Par4 in Endometrial Cancer  

Microsoft Academic Search

Recently, it has been shown that mice deficient in the pro- apoptotic protein prostate apoptosis response 4 (Par-4) are specifically prone to develop endometrial carcinomas. Based on this, we have examined here the possible role of Par-4 as a tumor suppressor gene in human endometrial cancer. Using cDNA arrays, quantitative reverse transcription-PCR, and immunohistochemistry, we detected Par-4 down-regulation in f40%

Gema Moreno-Bueno; Pablo J. Fernandez-Marcos; Manuel Collado; Mercedes J. Tendero; Isabel Garcia-Cao; David Hardisson; Jorge Moscat; Manuel Serrano; Jose Palacios

282

Common variants in the human platelet PAR4 thrombin receptor alter platelet function and differ by race.  

PubMed

Human platelets express 2 thrombin receptors: protease-activated receptor (PAR)-1 and PAR4. Recently, we reported 3.7-fold increased PAR4-mediated aggregation kinetics in platelets from black subjects compared with white subjects. We now show that platelets from blacks (n = 70) express 14% more PAR4 protein than those from whites (n = 84), but this difference is not associated with platelet PAR4 function. Quantitative trait locus analysis identified 3 common single nucleotide polymorphisms in the PAR4 gene (F2RL3) associated with PAR4-induced platelet aggregation. Among these single nucleotide polymorphisms, rs773902 determines whether residue 120 in transmembrane domain 2 is an alanine (Ala) or threonine (Thr). Compared with the Ala120 variant, Thr120 was more common in black subjects than in white subjects (63% vs 19%), was associated with higher PAR4-induced human platelet aggregation and Ca(2+) flux, and generated greater inositol 1,4,5-triphosphate in transfected cells. A second, less frequent F2RL3 variant, Phe296Val, was only observed in blacks and abolished the enhanced PAR4-induced platelet aggregation and 1,4,5-triphosphate generation associated with PAR4-Thr120. PAR4 genotype did not affect vorapaxar inhibition of platelet PAR1 function, but a strong pharmacogenetic effect was observed with the PAR4-specific antagonist YD-3 [1-benzyl-3(ethoxycarbonylphenyl)-indazole]. These findings may have an important pharmacogenetic effect on the development of new PAR antagonists. PMID:25293779

Edelstein, Leonard C; Simon, Lukas M; Lindsay, Cory R; Kong, Xianguo; Teruel-Montoya, Raúl; Tourdot, Benjamin E; Chen, Edward S; Ma, Lin; Coughlin, Shaun; Nieman, Marvin; Holinstat, Michael; Shaw, Chad A; Bray, Paul F

2014-11-27

283

IL2-Mediated Upregulation of uPA and uPAR in Natural Killer Cells  

Microsoft Academic Search

Urokinase plasminogen activator (uPA) and its receptor uPAR play a major role in immune cell-mediated, including natural killer (NK) cell-mediated, degradation of extracellular matrices. Herein, we investigate the effects of IL-2 on NK cell uPA and uPAR. RNA and protein analyses showed upregulation of uPA and uPAR following IL-2 stimulation. Gel-shift assays and Western blots detected uPA and uPAR mRNA

Gheath Al-Atrash; Sreerama Shetty; Steven Idell; Yaming Xue; Richard P. Kitson; Prathap Kumar Shetty Halady; Ronald H. Goldfarb

2002-01-01

284

Immunohistochemical analysis of the proapoptotic protein Par-4 in normal rat tissues.  

PubMed

Prostate apoptosis response 4 (par-4) is a recently identified gene that encodes a transcription factor, Par-4, with a leucine zipper domain. Par-4 protein is constitutively expressed in various cell lines and is functionally required but not sufficient for apoptosis. Induction of Par-4 in cultured cells is found exclusively during apoptosis, and ectopic overexpression of Par-4 enhances the potency of apoptotic stimuli. Western or Northern blot analysis on mRNA or protein extracts, respectively, from rat organs revealed that the expression of Par-4 was ubiquitous and was not restricted to any specific organ(s). To further identify specific cell types that expressed Par-4, we performed an immunohistochemical analysis of the protein in paraffin-embedded sections of various organs from rats. Our findings indicated that consistent with its proapoptotic role, Par-4 is expressed in apoptotic granulosa cells of atretic ovarian follicles and in terminally differentiated cells, such as the cardiomyocytes, cerebellar Purkinje cells, and pyramidal cells of the hypothalamus. Moreover, testosterone ablation by castration of rats caused an early and transient induction of Par-4 in the ductal cells of the prostate that undergo apoptosis. By contrast, in tissues in which the cells could be visually differentiated from their mature counterparts, Par-4 expression was lowest in the mature cells. This was the case for epithelia of the mammary and the prostate gland in which the basal cells maintained higher protein levels of Par-4 than did the terminally differentiated ductal cells. Similarly, cells of the stratum corneum of the skin and cells on top of the duodenal villi stained less intensely for Par-4 as compared to the stem cells in the stratum basale and at the bottom of the crypts of Lieberkühn, respectively. It is possible that Par-4 has to be down-regulated for successful differentiation in these tissues. Taken together, the widespread expression of Par-4 in various adult cell types underscores the physiological importance of the protein. The observation of constitutive Par-4 expression in the stem cell compartments is inconsistent with the probability of apoptosis per se and can be extended to determine whether Par-4 plays a role in other cellular processes. PMID:9269897

Boghaert, E R; Sells, S F; Walid, A J; Malone, P; Williams, N M; Weinstein, M H; Strange, R; Rangnekar, V M

1997-08-01

285

Cancer-Selective Apoptotic Effects of Extracellular and Intracellular Par-4  

PubMed Central

Selectivity toward cancer cells is the most desirable element in cancer therapeutics. Par-4 is a cancer cell-selective pro-apoptotic protein that functions intracellularly in the cytoplasmic and nuclear compartments, as a tumor suppressor. Moreover, recent findings indicate that the Par-4 protein is secreted by cells, and extracellular Par-4 induces cancer cell-specific apoptosis by interaction with the cell-surface receptor GRP78. This review describes the mechanisms underlying the apoptotic effects of both extracellular and intracellular Par-4 acting via its effector domain SAC. PMID:20440265

Bhattarai, Tripti Shrestha; Rangnekar, Vivek M.

2010-01-01

286

The PAR network: redundancy and robustness in a symmetry-breaking system  

PubMed Central

To become polarized, cells must first ‘break symmetry’. Symmetry breaking is the process by which an unpolarized, symmetric cell develops a singularity, often at the cell periphery, that is used to develop a polarity axis. The Caenorhabditis elegans zygote breaks symmetry under the influence of the sperm-donated centrosome, which causes the PAR polarity regulators to sort into distinct anterior and posterior cortical domains. Modelling analyses have shown that cortical flows induced by the centrosome combined with antagonism between anterior and posterior PARs (mutual exclusion) are sufficient, in principle, to break symmetry, provided that anterior and posterior PAR activities are precisely balanced. Experimental evidence indicates, however, that the system is surprisingly robust to changes in cortical flows, mutual exclusion and PAR balance. We suggest that this robustness derives from redundant symmetry-breaking inputs that engage two positive feedback loops mediated by the anterior and posterior PAR proteins. In particular, the PAR-2 feedback loop stabilizes the polarized state by creating a domain where posterior PARs are immune to exclusion by anterior PARs. The two feedback loops in the PAR network share characteristics with the two feedback loops in the Cdc42 polarization network of Saccharomyces cerevisiae. PMID:24062581

Motegi, Fumio; Seydoux, Geraldine

2013-01-01

287

EXPRIENCE D'HYDROSTATIQUE; PAR M. C.-E. WASTEELS.  

E-print Network

. Plongeons-le, d'abord par la partie AB, dans une éprouvette remplie de mercure e t d'eau ; la différence des'élève, à l'intérieur du tube, jusqu'en B. Dès que celui-ci plonge dans le mercure, l'eau contenue dans AB liquide dans l'éprouvette ; en même temps, on voit le mercure s'élever à l'intérieur du tube, au-dessus du

Boyer, Edmond

288

INSTITUT POLYTECHNIQUE DE GRENOBLE No attribu par la bibliothque  

E-print Network

-encadré par M. Bruno Raffin JURY wF toelyn Serot D résident wmeF prnçoise Baude D pporteur wF orsten Kuhlen D pporteur wF henis Trystram D hireteur de hèse wF fruno Raffin D goEendrnt tel-00459665,version1-24Feb2010 endré durnt m thèse et mon msterF t9i vriment ppréié les R nnées de trvil ensemleF te le remerie de m9

Paris-Sud XI, Université de

289

BOREAS TE-12 Incoming PAR Through the Forest Canopy Data  

NASA Technical Reports Server (NTRS)

The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-12 (Terrestrial Ecology) team collected photosynthetically active radiation (PAR) data sets in support of its efforts to characterize and interpret information on shoot geometry, leaf optical properties, leaf water potential, and leaf gas exchange. The data were collected at the Southern Study Area-Old Black Spruce (SSA-OBS) site from 04-Jul-1996 to 25-Jul-1996. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Walter-Shea, Elizabeth A.; Mesarch, Mark A.

2000-01-01

290

Inflammation and Macular Oedema after Pars Plana Vitrectomy  

PubMed Central

Cystoid macular oedema (CMO) is a major cause of reduced vision following intraocular surgery. Although the aetiology of CMO is not completely clarified, intraocular inflammation is known to play a major role in its development. The macula may develop cytotoxic oedema when the primary lesion and fluid accumulation occur in the parenchymatous cells (intracellular oedema) or vasogenic oedema when the primary defect occurs in the blood-retinal barrier and leads to extracellular fluid accumulation (extracellular oedema). We report on the mechanisms of CMO formation after pars plana vitrectomy and associated surgical procedures and discuss possible therapeutic approaches. PMID:24288446

Romano, Vito; Angi, Martina; del Grosso, Renata; Romano, Davide; Vinciguerra, Paolo; Romano, Mario R.

2013-01-01

291

Noncanonical PAR3 activation by factor Xa identifies a novel pathway for Tie2 activation and stabilization of vascular integrity.  

PubMed

Endothelial barrier protective effects of activated protein C (APC) require the endothelial protein C receptor (EPCR), protease-activated receptor (PAR) 1, and PAR3. In contrast, PAR1 and PAR3 activation by thrombin results in barrier disruption. Noncanonical PAR1 and PAR3 activation by APC vs canonical activation by thrombin provides an explanation for the functional selectivity of these proteases. Here we found that factor Xa (FXa) activated PAR1 at canonical Arg41 similar to thrombin but cleaved PAR3 at noncanonical Arg41 similar to APC. This unique PAR1-PAR3 activation profile permitted the identification of noncanonical PAR3 activation as a novel activation pathway for barrier protective tunica intima endothelial receptor tyrosine kinase 2 (Tie2). APC, FXa, and the noncanonical PAR3 tethered-ligand peptide induced prolonged activation of Tie2, whereas thrombin and the canonical PAR3 tethered-ligand peptide did not. Tie2 activation by FXa required PAR3 and EPCR. FXa and the noncanonical PAR3 tethered-ligand peptide induced Tie2- and PAR3-dependent upregulation of tight-junction-associated protein zona occludens 1 (ZO-1), translocation of ZO-1 to cell-cell borders, and the formation of typical ZO-1 honeycomb patterns that are indicative of tight-junction stabilization. These data provide intriguing novel insights into the diversification of functional selectivity of protease signaling achievable by canonical and noncanonical PAR activation, such as the activation of vascular-protective Tie2 by noncanonical PAR3 activation. PMID:25320242

Stavenuiter, Fabian; Mosnier, Laurent O

2014-11-27

292

The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis  

SciTech Connect

Research highlights: {yields} The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. {yields} L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. {yields} Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

Homma, Taihei [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)] [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shimizu, Miho [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)] [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Kuroda, Reiko, E-mail: ckuroda@mail.ecc.u-tokyo.ac.jp [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan) [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

2011-01-07

293

Effects of the conserved proteins, Soj (ParA) and SpoOJ (ParB) on chromosome partitioning in Bacillus subtilis  

E-print Network

The Par system contributes to stable inheritance of plasmids and chromosomes in diverse bacterial species. Faithful chromosome partitioning is important to dividing cells because anucleate, or chromosomeless, cells are not ...

Lee, Philina S. (Philina Sharlene), 1976-

2004-01-01

294

TUDE PAR ABSORPTION HERTZIENNE DE L'EAU ADSORBE SUR UN GEL DE SILICE Par M. KAN-TCHI KAMIYOSHI (*), et M. JEAN RIPOCHE (**),  

E-print Network

943. �TUDE PAR ABSORPTION HERTZIENNE DE L'EAU ADSORB�E SUR UN GEL DE SILICE Par M. KAN. Résumé. 2014 L'absorption hertzienne de l'eau adsorbée sur un gel de silice a été étudiée ici, en of the adsorbed water on silica-gel is studied here as a function of water content from 0% to 40

Boyer, Edmond

295

Shedding and cleavage of the urokinase receptor (uPAR): identification and characterisation of uPAR fragments in vitro and in vivo  

Microsoft Academic Search

Applying a novel, highly specific and sensitive immunoabsorption\\/Western blotting technique we have identified in vitro in conditioned cell culture medium and in vivo in human urine different soluble forms of the urokinase-type plasminogen activator receptor (uPAR\\/CD87). These include the uPAR fragment D2D3 and the never before identified domain 1 (D1) fragment. These forms correspond to fragments previously characterised as biologically

Nicolai Sidenius; Cornelis F. M Sier; Francesco Blasi

2000-01-01

296

Local-scale heterogeneity of photosynthetically active radiation (PAR), absorbed PAR and net radiation as a function of topography, sky conditions and leaf area index  

Microsoft Academic Search

The local-scale spatial distribution of photosynthetically active radiation (PAR), absorbed PAR (APAR) and net all-wave radiation (Q?) across the top of a forest canopy was investigated as a function of topography, sky conditions and forest heterogeneity for a forested hilly study site located in south-central Indiana, USA that is part of the FLUXNET and SpecNet networks. The method to estimate

Andrew Oliphant; C. Susan; B. Grimmond; Hans-Peter Schmid; Craig A. Wayson

2006-01-01

297

Concentration dependent dual effect of thrombin in endothelial cells via PAR-1 and PI3 kinase  

PubMed Central

Disruption of endothelial barrier is a critical pathophysiological factor in inflammation. Thrombin exerts a variety of cellular effects including inflammation and apoptosis through activation of the protease activated receptors (PARs). The activation of PAR-1 by thrombin is known to have a bimodal effect in endothelial cell permeability with a low concentration (pM levels) eliciting a barrier protective and a high concentration (nM levels) eliciting a barrier disruptive response. It is not known whether this PAR-1-dependent activity of thrombin is a unique phenomenon specific for the in vitro assay or it is part of a general anti-inflammatory effect of low concentrations of thrombin that may have a physiological relevance. Here, we report that low concentrations of thrombin or of PAR-1 agonist peptide induced significant anti-inflammatory activities. However, relatively high concentration of thrombin or of PAR-1 agonist peptide showed pro-inflammatory activities. By using function-blocking anti-PAR-1 antibodies and PI3 kinase inhibitor, we show that the direct anti-inflammatory effects of low concentrations of thrombin are dependent on the activation of PAR-1 and PI3 kinase. These results suggest a role for cross communication between PAR-1 activation and PI3 kinase pathway in mediating the cytoprotective effects of low concentrations of thrombin in the cytokine-stimulated endothelial cells. PMID:19189342

Bae, Jong-Sup; Kim, Yong-ung; Park, Moon-Ki; Rezaie, Alireza R.

2009-01-01

298

Reconnaissance de courriers manuscrits par HMMs contextuels et modle de langage  

E-print Network

Reconnaissance de courriers manuscrits par HMMs contextuels et modèle de langage Olivier Morillot manuscrites, sou- mis par les auteurs lors de la compétition ICDAR 2011 sur la reconnaissance de courriers en, adaptée à un système de reconnaissance de courriers qui comprend un prétraitement original des lignes, un

Paris-Sud XI, Université de

299

Prepar ation and proper ties of protein par ticles from human hair  

Microsoft Academic Search

Protein microspheres were conveniently prepared from human hair without chemical modification. The par ticle size was dependent on the mechanical stimuli and the aver age diameter was approximately 0.5 P m when the wet protein films were homogenized by mechanical stimuli using a Polytron and sonicator. The protein par ticles mainly consisted of D -ker atin types I and II.

Toshihiro Fujii; Kaoru Nakai; Hideto Kikuta; Shunichi Kobayashi; Toshihiro Hirai

2006-01-01

300

Optimisation par colonies de fourmis pour le problme du sac dos multidimensionnel  

E-print Network

Optimisation par colonies de fourmis pour le problème du sac à dos multidimensionnel Inès Alaya (Ant Colony Optimization / ACO) pour résoudre le problème du sac à dos multidimensionnel. L competitive results. MOTS-CL�S : Optimisation par colonies de fourmis, Problème du sac à dos multidimensionnel

Solnon, Christine

301

La perception des changements comptables par les acteurs : le cas du Vit-Nam  

E-print Network

of their profile; (2) it appears that the perception concerning the conceptual changes and the practical changes1 La perception des changements comptables par les acteurs : le cas du Viêt-Nam Nhu Tuyên Lê déterminants de la perception des changements comptables par les acteurs mêmes de la Comptabilité, dans le

Paris-Sud XI, Université de

302

Adult fish and ichthyoplankton of Par Pond and Pond B. Interim report, December 1983-May 1984  

SciTech Connect

The objective was to characterize the fish community of Par Pond and investigate the relative impacts of thermal effects, trophic effects and other factors on the ecology of Par Pond fishes. This report presents data collected from the first six months of the study. 18 figs., 16 tabs. (ACR)

Paller, M.; O'Hara, J.; Hughes, D.

1985-04-01

303

LUMINESCENCE DU SULFURE DE CADMIUM EXCIT PAR LASER (*) R. LEVY, A. BIVAS et J. B. GRUN  

E-print Network

507 LUMINESCENCE DU SULFURE DE CADMIUM EXCIT� PAR LASER (*) R. LEVY, A. BIVAS et J. B. GRUN 12 février 1970)] Résumé. 2014 La luminescence excitonique du Sulfure de Cadmium excité par des sources intenses (lasers) a été étudiée. La raie la plus intense du spectre de luminescence obtenue dans

Paris-Sud XI, Université de

304

Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering analysis  

E-print Network

1 Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering.antonius@nyumc.org #12;2 Abstract Background: Paternal age related schizophrenia (PARS) has been proposed as a subgroup of schizophrenia with distinct etiology, pathophysiology and symptoms. This study uses a k-means clustering

Ahn, Hongshik

305

Contribution du Gipsa lab au projet ANR LURGA Localisation d'Urgence Reconfigurable par GALILEO .  

E-print Network

1 Contribution du Gipsa lab au projet ANR LURGA � Localisation d'Urgence Reconfigurable par GALILEO r�ception des signaux GALILEO n'est pas perturb�e. Zone de crise avec canal de propagation perturb� par des trajets multiples Station de base 1 Constellation de satellites GALILEO Station de base 2

Boyer, Edmond

306

Bacterial DNA segregation dynamics mediated by the polymerizing protein ParF.  

PubMed

Prokaryotic DNA segregation most commonly involves members of the Walker-type ParA superfamily. Here we show that the ParF partition protein specified by the TP228 plasmid is a ParA ATPase that assembles into extensive filaments in vitro. Polymerization is potentiated by ATP binding and does not require nucleotide hydrolysis. Analysis of mutations in conserved residues of the Walker A motif established a functional coupling between filament dynamics and DNA partitioning. The partner partition protein ParG plays two separable roles in the ParF polymerization process. ParF is unrelated to prokaryotic polymerizing proteins of the actin or tubulin families, but is a homologue of the MinD cell division protein, which also assembles into filaments. The ultrastructures of the ParF and MinD polymers are remarkably similar. This points to an evolutionary parallel between DNA segregation and cytokinesis in prokaryotic cells, and reveals a potential molecular mechanism for plasmid and chromosome segregation mediated by the ubiquitous ParA-type proteins. PMID:15775965

Barillà, Daniela; Rosenberg, Mark F; Nobbmann, Ulf; Hayes, Finbarr

2005-04-01

307

Structural Mechanism of ATP-induced Polymerization of the Partition Factor ParF  

PubMed Central

Segregation of the bacterial multidrug resistance plasmid TP228 requires the centromere-binding protein ParG, the parH centromere, and the Walker box ATPase ParF. The cycling of ParF between ADP- and ATP-bound states drives TP228 partition; ATP binding stimulates ParF polymerization, which is essential for segregation, whereas ADP binding antagonizes polymerization and inhibits DNA partition. The molecular mechanism involved in this adenine nucleotide switch is unclear. Moreover, it is unknown how any Walker box protein polymerizes in an ATP-dependent manner. Here, we describe multiple ParF structures in ADP- and phosphomethylphosphonic acid adenylate ester (AMPPCP)-bound states. ParF-ADP is monomeric but dimerizes when complexed with AMPPCP. Strikingly, in ParF-AMPPCP structures, the dimers interact to create dimer-of-dimer “units” that generate a specific linear filament. Mutation of interface residues prevents both polymerization and DNA segregation in vivo. Thus, these data provide insight into a unique mechanism by which a Walker box protein forms polymers that involves the generation of ATP-induced dimer-of-dimer building blocks. PMID:22674577

Schumacher, Maria A.; Ye, Qiaozhen; Barge, Madhuri T.; Zampini, Massimiliano; Barilla, Daniela; Hayes, Finbarr

2012-01-01

308

PAR extinction in shortgrass ecosystems: effects of clumping, sky conditions and soil albedo  

Microsoft Academic Search

The amount of photosynthetically active radiation (PAR) absorbed by a canopy (APAR) is an important driving variable for vegetation processes such as photosynthesis. PAR extinction in clumped canopies of shortgrass ecosystems is the focus of this paper. Directional gap fractions estimated at peak biomass on several Mexican shortgrass ecosystems with a hemispherical radiation sensor (Li-Cor, LAI-2000) were higher than those

Yann Nouvellon; Agnès Bégué; M. Susan Morana; Danny Lo Seen; Serge Rambal; Delphine Luquet; Ghani Chehbouni; Yoshio Inoue

2000-01-01

309

Ultrastructure of the pituitary gland (pars distalis) in sockeye salmon ( Oncorhynchus nerka ) during gonad maturation  

Microsoft Academic Search

The fine structure of the various hormone-producing cell types (with the exclusion of the prolactin cells) in the pituitary gland (pars distalis) of migratory sockeye salmon is described. All fish were in an advanced stage of sexual maturation. In the proximal pars distalis five cell types were distinguished: growth hormone cells, ACTH cells, gonadotrops, “vesicular cells”, and “chromophobe cells”. Gonadotrops

H. Cook; A. P. van Overbeeke

1972-01-01

310

12 CFR 1263.19 - Par value and price of stock.  

...2014-01-01 false Par value and price of stock. 1263.19 Section... Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME... § 1263.19 Par value and price of stock. The capital...the Director has fixed a higher...

2014-01-01

311

12 CFR 1263.19 - Par value and price of stock.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Par value and price of stock. 1263.19 Section... Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME... § 1263.19 Par value and price of stock. The capital...the Director has fixed a higher...

2012-01-01

312

12 CFR 1263.19 - Par value and price of stock.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Par value and price of stock. 1263.19 Section... Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME... § 1263.19 Par value and price of stock. The capital...the Director has fixed a higher...

2011-01-01

313

12 CFR 925.19 - Par value and price of stock.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Par value and price of stock. 925.19 Section 925.19 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN...Requirements § 925.19 Par value and price of stock. The capital stock...

2010-01-01

314

12 CFR 1263.19 - Par value and price of stock.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Par value and price of stock. 1263.19 Section... Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME... § 1263.19 Par value and price of stock. The capital...the Director has fixed a higher...

2013-01-01

315

Bacterial DNA segregation dynamics mediated by the polymerizing protein ParF  

PubMed Central

Prokaryotic DNA segregation most commonly involves members of the Walker-type ParA superfamily. Here we show that the ParF partition protein specified by the TP228 plasmid is a ParA ATPase that assembles into extensive filaments in vitro. Polymerization is potentiated by ATP binding and does not require nucleotide hydrolysis. Analysis of mutations in conserved residues of the Walker A motif established a functional coupling between filament dynamics and DNA partitioning. The partner partition protein ParG plays two separable roles in the ParF polymerization process. ParF is unrelated to prokaryotic polymerizing proteins of the actin or tubulin families, but is a homologue of the MinD cell division protein, which also assembles into filaments. The ultrastructures of the ParF and MinD polymers are remarkably similar. This points to an evolutionary parallel between DNA segregation and cytokinesis in prokaryotic cells, and reveals a potential molecular mechanism for plasmid and chromosome segregation mediated by the ubiquitous ParA-type proteins. PMID:15775965

Barilla, Daniela; Rosenberg, Mark F; Nobbmann, Ulf; Hayes, Finbarr

2005-01-01

316

Modelisation et analyse des syst`emes Duree: 4h. Une feuille par question.  

E-print Network

- bies et un groupe d'^etres humains "normaux" (non zombies). Il est bien connu que lorsqu'un zombie touche un ^etre humain, ce dernier se transforme en zombie. Par ailleurs, la panique provoqu´ee dans le camp des humains par la pr´esence des zombies cr´ee un rapprochement entre les humains, rapprochement

Catholique de Louvain, Université

317

Par-4 inhibits Akt and suppresses Ras-induced lung tumorigenesis  

PubMed Central

The atypical PKC-interacting protein, Par-4, inhibits cell survival and tumorigenesis in vitro, and its genetic inactivation in mice leads to reduced lifespan, enhanced benign tumour development and low-frequency carcinogenesis. Here, we demonstrate that Par-4 is highly expressed in normal lung but reduced in human lung cancer samples. We show, in a mouse model of lung tumours, that the lack of Par-4 dramatically enhances Ras-induced lung carcinoma formation in vivo, acting as a negative regulator of Akt activation. We also demonstrate in cell culture, in vivo, and in biochemical experiments that Akt regulation by Par-4 is mediated by PKC?, establishing a new paradigm for Akt regulation and, likely, for Ras-induced lung carcinogenesis, wherein Par-4 is a novel tumour suppressor. PMID:18650932

Joshi, Jayashree; Fernandez-Marcos, Pablo J; Galvez, Anita; Amanchy, Ramars; Linares, Juan F; Duran, Angeles; Pathrose, Peterson; Leitges, Michael; Canamero, Marta; Collado, Manuel; Salas, Clara; Serrano, Manuel; Moscat, Jorge; Diaz-Meco, Maria T

2008-01-01

318

Loss of the Par3 Polarity Protein Promotes Breast Tumorigenesis and Metastasis  

PubMed Central

Loss of epithelial organization is a hallmark of carcinomas, but whether polarity regulates tumor growth and metastasis is poorly understood. To address this issue we depleted the Par3 polarity gene by RNAi in combination with oncogenic Notch or Ras61L expression in the murine mammary gland. Par3 silencing dramatically reduced tumor latency in both models, and produced invasive and metastatic tumors that retained epithelial marker expression. Par3 depletion was associated with induction of MMP9, destruction of the extracellular matrix, and invasion, all mediated by atypical PKC-dependant JAK/Stat3 activation. Importantly, Par3 expression is significantly reduced in human breast cancers, which correlates with active aPKC and Stat3. These data identify Par3 as a regulator of signaling pathways relevant to invasive breast cancer. PMID:23153534

McCaffrey, Luke Martin; Montalbano, JoAnne; Mihai, Constantina; Macara, Ian G.

2012-01-01

319

PAR proteins and the establishment of cell polarity during C. elegans development.  

PubMed

Cells become polarized to develop functional specializations and to distribute developmental determinants unequally during division. Studies that began in the nematode C. elegans have identified a group of largely conserved proteins, called PAR proteins, that play key roles in the polarization of many different cell types. During initial stages of cell polarization, certain PAR proteins become distributed asymmetrically along the cell cortex and subsequently direct the localization and/or activity of other proteins. Here I discuss recent findings on how PAR proteins become and remain asymmetric in three different contexts during C. elegans development: anterior-posterior polarization of the one-cell embryo, apicobasal polarization of non-epithelial early embryonic cells, and apicobasal polarization of epithelial cells. Although polarity within each of these cell types requires PAR proteins, the cues and regulators of PAR asymmetry can differ. PMID:15666355

Nance, Jeremy

2005-02-01

320

Cell Polarity Factor Par3 Binds SPTLC1 and Modulates Monocyte Serine Palmitoyltransferase Activity and Chemotaxis*  

PubMed Central

Elevated sphingolipids have been associated with increased cardiovascular disease. Conversely, atherosclerosis is reduced in mice by blocking de novo synthesis of sphingolipids catalyzed by serine palmitoyltransferase (SPT). The SPT enzyme is composed of the SPTLC1 and -2 subunits, and here we describe a novel protein-protein interaction between SPTLC1 and the PDZ protein Par3 (partitioning defective protein 3). Mammalian SPTLC1 orthologs have a highly conserved C terminus that conforms to a type II PDZ protein interaction motif, and by screening PDZ domain protein arrays with an SPTLC1 C-terminal peptide, we found it bound the third PDZ domain of Par3. Overlay and immunoprecipitation assays confirmed this interaction and indicate Par3 is able to associate with the SPTLC1/2 holoenzyme by binding the C-terminal SPTLC1 PDZ motif. The physiologic existence of the SPTLC1/2-Par3 complex was detected in mouse liver and macrophages, and short interfering RNA inhibition of Par3 in human THP-1 monocytes significantly reduced SPT activity and de novo ceramide synthesis by nearly 40%. Given monocyte recruitment into inflamed vessels is thought to promote atherosclerosis, and because Par3 and sphingolipids have been associated with polarized cell migration, we tested whether the ability of THP-1 monocytes to migrate toward MCP-1 (monocyte chemoattractant protein 1) depended upon Par3 and SPTLC1 expression. Knockdown of Par3 significantly reduced MCP1-induced chemotaxis of THP-1 monocytes, as did knockdown of SPTLC1, and this Par3 effect depended upon SPT activity and was blunted by ceramide treatment. In conclusion, protein arrays were used to identify a novel SPTLC1-Par3 interaction that associates with increased monocyte serine palmitoyltransferase activity and chemotaxis toward inflammatory signals. PMID:19592499

Tamehiro, Norimasa; Mujawar, Zahedi; Zhou, Suiping; Zhuang, Debbie Z.; Hornemann, Thorsten; von Eckardstein, Arnold; Fitzgerald, Michael L.

2009-01-01

321

Substituted indoles as selective protease activated receptor 4 (PAR-4) antagonists: Discovery and SAR of ML354.  

PubMed

Herein we report the discovery and SAR of an indole-based protease activated receptor-4 (PAR-4) antagonist scaffold derived from a similarity search of the Vanderbilt HTS collection, leading to MLPCN probe ML354 (VU0099704). Using a novel PAC-1 fluorescent ?IIb?3 activation assay this probe molecule antagonist was found to have an IC50 of 140nM for PAR-4 with 71-fold selectivity versus PAR-1 (PAR-1IC50=10?M). PMID:25176330

Wen, Wandong; Young, Summer E; Duvernay, Matthew T; Schulte, Michael L; Nance, Kellie D; Melancon, Bruce J; Engers, Julie; Locuson, Charles W; Wood, Michael R; Daniels, J Scott; Wu, Wenjun; Lindsley, Craig W; Hamm, Heidi E; Stauffer, Shaun R

2014-10-01

322

Revue. Volume X n x/anne, pages 1 X Suivi d'endommagement par EA dans un  

E-print Network

Revue. Volume X ­ n° x/année, pages 1 à X Suivi d'endommagement par EA dans un composite obtenu par matériau composite à fibres de verre et à matrice vinylester, obtenu par pultrusion, est soumis à un mode d'endommagement, gouverné principalement par les divers micro-mécanismes d'endommagement de la

Paris-Sud XI, Université de

323

PROBABILIT DE TRANSITION DE LA RAIE 61S0 -63P0 DU MERCURE Par Mlle M. C. BIGEON,  

E-print Network

51. PROBABILIT� DE TRANSITION DE LA RAIE 61S0 - 63P0 DU MERCURE Par Mlle M. C. BIGEON, Faculté des raie interdite (61S0 2014 63P0) du mercure est émise par les isotopes impairs 199Hg et 201Hg de spin expérimentalement par des mesures d'absorption de la raie interdite par la vapeur de mercure. L'accord est

Paris-Sud XI, Université de

324

Pars flaccida perforation in tissue culture: morphological study.  

PubMed

Subtotal pars flaccida perforation was effected in vitro in rat tympanic membranes. The drums were subsequently kept in tissue culture and after various intervals studied by means of light and scanning electron microscopy. No complete covering of the perforation was seen, though a marked thickening and hyperplasia of the outer, keratinizing, squamous epithelium (OE) was evident. The inner, tympanal epithelium (IE) appeared swollen, containing rounded structures in the cytoplasm especially close to the contact area with the OE. Ingrowth of OE onto the tympanal side of the drum was seen particularly in the areas where the IE was sparse and completely lacking. Complete covering of a drum perforation seems to be dependent on the formation of supporting granulation tissue, probably resulting from an inflammatory reaction in the healing area. PMID:2324630

Stenfors, L E; Olsen, E G; Henriksen, A O

1990-02-01

325

Myopathy in horses with pituitary pars intermedia dysfunction (Cushing's disease).  

PubMed

Fifteen horses with pituitary pars intermedia dysfunction were studied. The horses were of various breeds and between 15 and 28 years of age. Control horses matched for breed and age were studied for comparison. Evaluations included complete blood cell count and serum biochemical analysis, electromyography, and gluteus medius muscle biopsies for histochemical, morphometric, and ultrastructural analysis. No differences were found between groups of horses on routine laboratory analysis or electromyography. We demonstrated that muscle wasting in diseased horses was the result of atrophy of types 2A and 2B muscle fibers and loss of type 2B myofibers. Mild non-specific non-inflammatory myopathic alterations such as myofiber size variation, internal nuclei, perimysial, endomysial and sarcoplasmic fat accumulation were observed. At the ultrastructural level, subsarcolemmal mitochondrial accumulation and increased lipid droplets were evident. Similar to other species, this study confirmed atrophy of type 2 fibers as the cause of muscle mass loss in horses with Cushing's disease. PMID:17005399

Aleman, M; Watson, J L; Williams, D C; LeCouteur, R A; Nieto, J E; Shelton, G D

2006-11-01

326

Pars plana vitrectomy through the Boston Keratoprosthesis type 1  

PubMed Central

Purpose To ascertain the feasibility of pars plana vitrectomy (PPV) through a permanent Boston Keratoprosthesis type 1 (KPro) without the use of a temporary KPro. Methods A retrospective interventional case series. Eyes implanted with Boston KPro type 1 between 2008 and 2011 requiring PPV for vitreoretinal complications were included. Feasibility of PPV through the KPro, its anatomical and functional success were studied. Results Five out of 70 patients required PPV for vitreoretinal complications post-KPro surgery resulting in an incidence of 7%. PPV was feasible through the Boston KPro with no deleterious effects on the corneal carrier or the KPro itself. Repeat PPV was necessary in some cases. Although anatomical repair of the vitreoretinal complications was achieved in most cases, post PPV visual acuity remained poor in the majority. Conclusion Our study suggests that although PPV through the Boston KPro is a viable approach for vitreoretinal disease repair, visual rehabilitation remains poor. PMID:23579405

Harissi-Dagher, M; Durr, G M; Biernacki, K; Sebag, M; Rheaume, M-A

2013-01-01

327

[Problems in pars plana vitrectomy in complicated diabetic retinopathy].  

PubMed

Introduction summarizes basal indications for pars plana vitrectomy (PPV) in complicated diabetic retinopathy (DR) and indications for urgently performed PPV are accentuated. Further there are explained various peculiarities of PPV in DR, various components forming the solution for infusion, advantages of the cerclage, some problems with surgery of the complicated cataracts, contribution and indications of the use of the silicone oil for the inner tamponade. Special attention was paid to the postoperative complications affecting the cornea, rubeosis iridis, iatrogenic tears of the retina and recurring intravitreal hemorrhages. Thereafter author concludes this review evaluating prognosis and long-term results of PPV and DR. He emphasizes the technical difficulties of this operation and recommends to concentrate the performance of this operation into the centres specialized for vitreoretinal surgery. PMID:2713920

Karel, I

1989-03-01

328

Proteinase-activated receptors (PARs) - focus on receptor-receptor-interactions and their physiological and pathophysiological impact  

PubMed Central

Proteinase-activated receptors (PARs) are a subfamily of G protein-coupled receptors (GPCRs) with four members, PAR1, PAR2, PAR3 and PAR4, playing critical functions in hemostasis, thrombosis, embryonic development, wound healing, inflammation and cancer progression. PARs are characterized by a unique activation mechanism involving receptor cleavage by different proteinases at specific sites within the extracellular amino-terminus and the exposure of amino-terminal “tethered ligand“ domains that bind to and activate the cleaved receptors. After activation, the PAR family members are able to stimulate complex intracellular signalling networks via classical G protein-mediated pathways and beta-arrestin signalling. In addition, different receptor crosstalk mechanisms critically contribute to a high diversity of PAR signal transduction and receptor-trafficking processes that result in multiple physiological effects. In this review, we summarize current information about PAR-initiated physical and functional receptor interactions and their physiological and pathological roles. We focus especially on PAR homo- and heterodimerization, transactivation of receptor tyrosine kinases (RTKs) and receptor serine/threonine kinases (RSTKs), communication with other GPCRs, toll-like receptors and NOD-like receptors, ion channel receptors, and on PAR association with cargo receptors. In addition, we discuss the suitability of these receptor interaction mechanisms as targets for modulating PAR signalling in disease. PMID:24215724

2013-01-01

329

NUMERUS CLAUSUS DU CONCOURS DE MAIEUTIQUE Par arrt du 5 novembre 2010, le nombre d'tudiants de premire anne  

E-print Network

NUMERUS CLAUSUS DU CONCOURS DE MAIEUTIQUE 2011 Par arrêté du 5 novembre 2010, le nombre d. #12;NUMERUS CLAUSUS DU CONCOURS DE MEDECINE 2011 Par arrêté du 5 novembre 2010, le nombre d;NUMERUS CLAUSUS DU CONCOURS D'ODONTOLOGIE 2011 Par arrêté du 5 novembre 2010, le nombre d'étudiants de

Jeanjean, Louis

330

D-Serine is reabsorbed in rat renal pars recta.  

PubMed

D-Serine normally contributes up to 3% to total plasma serine and up to 23% in chronic renal failure. D-Serine is metabolized by tubular D-amino acid oxidase (D-AAO), and high D-serine plasma levels are nephrotoxic; both events are localized in the straight part of the proximal tubule. We therefore investigated if and how D-serine is reabsorbed there. We microinfused 14C-labeled D- or -L-serine + [3H]inulin into early proximal (EP), late proximal (LP), or early distal (ED) tubule sections of superficial nephrons and into long loops of Henle (LLH) of rats in vivo and in situ. The fractional reabsorption (FR) of the 14C label was determined from the 14C:3H ratio in the final urine. At 0.36 mM, FR of D-[14C]serine was 86% (EP), 90% (LP), and approximately 0 (ED, LLH). FR of D-serine could be saturated and inhibited by L-serine (and vice versa). D-methionine, but not D-glutamate or D-arginine, blocked FR of D-serine (LP). We conlude that filtered D-serine is able to enter the pars recta cells, thereby getting access to D-AAO. The uptake carrier has a very low stereospecificity and is, therefore, different from that in the proximal convolution. The colocalization of exclusive reabsorption and metabolism makes the pars recta the tubule site for the recycling of the carbon structure of D-amino acids and, at the same time, the target of D-serine nephrotoxicity. PMID:10362774

Silbernagl, S; Völker, K; Dantzler, W H

1999-06-01

331

Targeting uPAR with Antagonistic Recombinant Human Antibodies in Aggressive Breast Cancer  

PubMed Central

Components of the plasminogen activation system (PAS) which are overexpressed in aggressive breast cancer subtypes offer appealing targets for development of new diagnostics and therapeutics. By comparing gene expression data in patient populations and cultured cell lines, we identified elevated levels of the urokinase plasminogen activation receptor (uPAR, PLAUR) in highly aggressive breast cancer subtypes and cell lines. Recombinant human anti-uPAR antagonistic antibodies exhibited potent binding in vitro to the surface of cancer cells expressing uPAR. In vivo these antibodies detected uPAR expression in triple negative breast cancer (TNBC) tumor xenografts using near infrared (NIR) imaging and 111In single-photon emission computed tomography (SPECT). Antibody-based uPAR imaging probes accurately detected small disseminated lesions in a tumor metastasis model, complementing the current clinical imaging standard 18F-fluorodeoxyglucose (FDG) at detecting non-glucose-avid metastatic lesions. A monotherapy study using the antagonistic antibodies resulted in a significant decrease in tumor growth in a TNBC xenograft model. Additionally, a radioimmunotherapy (RIT) study, using the anti-uPAR antibodies conjugated to the therapeutic radioisotope 177Lu, found that they were effective at reducing tumor burden in vivo. Taken together, our results offer a preclinical proof of concept for uPAR targeting as a strategy for breast cancer diagnosis and therapy using this novel human antibody technology. PMID:23400595

LeBeau, Aaron M.; Duriseti, Sai; Murphy, Stephanie T.; Pepin, Francois; Hann, Byron; Gray, Joe W.; VanBrocklin, Henry F.; Craik, Charles S.

2013-01-01

332

Evidence for a DNA-relay mechanism in ParABS-mediated chromosome segregation  

PubMed Central

The widely conserved ParABS system plays a major role in bacterial chromosome segregation. How the components of this system work together to generate translocation force and directional motion remains uncertain. Here, we combine biochemical approaches, quantitative imaging and mathematical modeling to examine the mechanism by which ParA drives the translocation of the ParB/parS partition complex in Caulobacter crescentus. Our experiments, together with simulations grounded on experimentally-determined biochemical and cellular parameters, suggest a novel 'DNA-relay' mechanism in which the chromosome plays a mechanical function. In this model, DNA-bound ParA-ATP dimers serve as transient tethers that harness the elastic dynamics of the chromosome to relay the partition complex from one DNA region to another across a ParA-ATP dimer gradient. Since ParA-like proteins are implicated in the partitioning of various cytoplasmic cargos, the conservation of their DNA-binding activity suggests that the DNA-relay mechanism may be a general form of intracellular transport in bacteria. DOI: http://dx.doi.org/10.7554/eLife.02758.001 PMID:24859756

Lim, Hoong Chuin; Surovtsev, Ivan Vladimirovich; Beltran, Bruno Gabriel; Huang, Fang; Bewersdorf, Jorg; Jacobs-Wagner, Christine

2014-01-01

333

Cathepsin S Signals via PAR2 and Generates a Novel Tethered Ligand Receptor Agonist  

PubMed Central

Protease-activated receptor-2 is widely expressed in mammalian epithelial, immune and neural tissues. Cleavage of PAR2 by serine proteases leads to self-activation of the receptor by the tethered ligand SLIGRL. The contribution of other classes of proteases to PAR activation has not been studied in detail. Cathepsin S is a widely expressed cysteine protease that is upregulated in inflammatory conditions. It has been suggested that cathepsin S activates PAR2. However, cathepsin S activation of PAR2 has not been demonstrated directly nor has the potential mechanism of activation been identified. We show that cathepsin S cleaves near the N-terminus of PAR2 to expose a novel tethered ligand, KVDGTS. The hexapeptide KVDGTS generates downstream signaling events specific to PAR2 but is weaker than SLIGRL. Mutation of the cathepsin S cleavage site prevents receptor activation by the protease while KVDGTS retains activity. In conclusion, the range of actions previously ascribed to cysteine cathepsins in general, and cathepsin S in particular, should be expanded to include molecular signaling. Such signaling may link together observations that had been attributed previously to PAR2 or cathepsin S individually. These interactions may contribute to inflammation. PMID:24964046

Lerner, Ethan A.

2014-01-01

334

Aberrations in Pseudoautosomal Regions (PARs) Found in Infertile Men with Y-Chromosome Microdeletions  

PubMed Central

Context: The pseudoautosomal regions (PARs) of the Y-chromosome undergo meiotic recombination with the X-chromosome. PAR mutations are associated with infertility and mental and stature disorders. Objective: The aim of the study was to determine whether men with Y-chromosome microdeletions have structural defects in PARs. Design and Participants: Eighty-seven infertile men with Y-chromosome microdeletions and 35 controls were evaluated for chromosomal rearrangements using commercial or custom (X- and Y-chromosome) array comparative genomic hybridization or by quantitative PCR of selected PAR genes. Multisoftware-defined chromosomal gains or losses were validated by quantitative PCR and FISH. Results: Array comparative genomic hybridization confirmed the AZF deletions identified by multiplex PCR. All men with Y-chromosome microdeletions and an abnormal karyotype displayed PAR abnormalities, as did 10% of men with Y-chromosome microdeletions and a normal karyotype. None of the control subjects or infertile men without Y-chromosome microdeletions had PAR duplications or deletions. SHOX aberrations occurred in 14 men (nine gains and five losses); four were short in stature (<10th percentile), and one was tall (>95th percentile). In contrast, the height of 23 men with Y-chromosome microdeletions and normal PARs was average at 176.8 cm (50th percentile). Conclusions: Y-chromosome microdeletions can include PAR defects causing genomic disorders such as SHOX, which may be transmitted to offspring. Previously unrecognized PAR gains and losses in men with Y-chromosome microdeletions may have consequences for offspring. PMID:21252244

Weedin, John W.; Sahin, Aysegul; Tannour-Louet, Mounia; Han, Shuo; Bournat, Juan C.; Mielnik, Anna; Cheung, Sau Wai; Nangia, Ajay K.; Schlegel, Peter N.; Lipshultz, Larry I.

2011-01-01

335

Thrombin induces rapid PAR1-mediated non-classical FGF1 release  

SciTech Connect

Thrombin induces cell proliferation and migration during vascular injury. We report that thrombin rapidly stimulated expression and release of the pro-angiogenic polypeptide fibroblast growth factor 1 (FGF1). Thrombin failed to induce FGF1 release from protease-activated receptor 1 (PAR1) null fibroblasts, indicating that this effect was dependent on PAR1. Similarly to thrombin, FGF1 expression and release were induced by TRAP, a specific oligopeptide agonist of PAR1. These results identify a novel aspect of the crosstalk between FGF and thrombin signaling pathways which both play important roles in tissue repair and angiogenesis.

Duarte, Maria [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Kolev, Vihren [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Soldi, Raffaella [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Kirov, Alexander [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Graziani, Irene [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Oliveira, Silvia Marta [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Kacer, Doreen [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Friesel, Robert [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Maciag, Thomas [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States); Prudovsky, Igor [Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074 (United States)]. E-mail: prudoi@mmc.org

2006-11-24

336

Par-complex aPKC and Par3 cross-talk with innate immunity NF-?B pathway in epithelial cells  

PubMed Central

Summary Components of the Par-complex, atypical PKC and Par3, have been found to be downregulated upon activation of NF-?B in intestinal epithelial cells. To determine their possible role in pro-inflammatory responses we transduced Caco-2 human colon carcinoma cells with constitutively active (ca) PKC? or anti-Par3 shRNA-expressing lentiviral particles. Contrary to previous reports in other cell types, ca-PKC? did not activate, but rather decreased, baseline NF-?B activity in a luminiscence reporter assay. An identical observation applied to a PB1 domain deletion PKC?, which fails to localize to the tight-junction. Conversely, as expected, the same ca-PKC? activated NF-?B in non-polarized HEK293 cells. Likewise, knockdown of Par3 increased NF-?B activity and, surprisingly, greatly enhanced its response to TNF?, as shown by transcription of IL-8, GRO-1, GRO-2 and GRO-3. We conclude that aPKC and Par3 are inhibitors of the canonical NF-?B activation pathway, although perhaps acting through independent pathways, and may be involved in pro-inflammatory responses. PMID:24244864

Forteza, Radia; Wald, Flavia A.; Mashukova, Anastasia; Kozhekbaeva, Zhanna; Salas, Pedro J.

2013-01-01

337

Regulation of the proapoptotic functions of prostate apoptosis response-4 (Par-4) by casein kinase 2 in prostate cancer cells  

PubMed Central

The proapoptotic protein, prostate apoptosis response-4 (Par-4), acts as a tumor suppressor in prostate cancer cells. The serine/threonine kinase casein kinase 2 (CK2) has a well-reported role in prostate cancer resistance to apoptotic agents or anticancer drugs. However, the mechanistic understanding on how CK2 supports survival is far from complete. In this work, we demonstrate both in rat and humans that (i) Par-4 is a new substrate of the survival kinase CK2 and (ii) phosphorylation by CK2 impairs Par-4 proapoptotic functions. We also unravel different levels of CK2-dependent regulation of Par-4 between species. In rats, the phosphorylation by CK2 at the major site, S124, prevents caspase-mediated Par-4 cleavage (D123) and consequently impairs the proapoptotic function of Par-4. In humans, CK2 strongly impairs the apoptotic properties of Par-4, independently of the caspase-mediated cleavage of Par-4 (D131), by triggering the phosphorylation at residue S231. Furthermore, we show that human Par-4 residue S231 is highly phosphorylated in prostate cancer cells as compared with their normal counterparts. Finally, the sensitivity of prostate cancer cells to apoptosis by CK2 knockdown is significantly reversed by parallel knockdown of Par-4. Thus, Par-4 seems a critical target of CK2 that could be exploited for the development of new anticancer drugs. PMID:24457960

de Thonel, A; Hazoume, A; Kochin, V; Isoniemi, K; Jego, G; Fourmaux, E; Hammann, A; Mjahed, H; Filhol, O; Micheau, O; Rocchi, P; Mezger, V; Eriksson, J E; Rangnekar, V M; Garrido, C

2014-01-01

338

HiPAR-DSP 16: a new DSP for onboard real-time SAR systems  

NASA Astrophysics Data System (ADS)

In this paper we present the HiPAR-DSP 16, a parallel and programmable processor architecture which is adapted to the demands of SAR image processing. TO provide a high performance, the HiPAR-DSP 16 features an array of 16 parallel processing units. Each of these processing units can process up to 3 instructions per clock cycle. Efficient data exchange between the processing units can be done by a shared memory with concurrent access. The HiPAR-DSP 16 is able to perform a 4096 samples complex FFT in 154 microsecond(s) and a compete (omega) k SAR processing algorithm on 4k range line with a PRF of more than 200 Hz in real-time. This shows the high capability of the HiPAR-DSP 16 for onboard real-time SAR systems.

Kloos, Helge; Friebe, Lars; Wittenburg, Jens P.; Hinrichs, Willm; Lieske, Hanno; Pirsch, Peter

2001-07-01

339

Hormone de croissance placentaire. Signification par rapport aux hormones de croissance et  

E-print Network

Hormone de croissance placentaire. Signification par rapport aux hormones de croissance et. Placentalgrowth hormone. Significance relative to pituitary growth hormo- nes and placental lactogen hormone growth hormone (PGH). This entity, agonist of pituitary GH, appears responsible for the elevated IGFI

Boyer, Edmond

340

INSTITUT NATIONAL POLYTECHNIQUE DE GRENOBLE N o attribu par la bibliothque  

E-print Network

CHETOUANI Le 28 novembre 2007 MICROSYSTEMES ET MICROMANIPULATION A LEVITATION DIAMAGNETIQUE CONCEPTION » présentée et soutenue publiquement par Hichem Lamri CHETOUANI Le 28 novembre 2007 MICROSYSTEMES ET

Paris-Sud XI, Université de

341

Caractrisation des hydrolases scrtes par les champignons anarobies M. HEBRAUD M. FEVRE  

E-print Network

cellulase Trichoderma reesei C30 (5). L'isolement et l'identification par le laboratoire de microbiologie à population of the rumen includes anaerobic phycomycetes in addition to bacteria and protozoa (11

Paris-Sud XI, Université de

342

Model parameterization to simulate and compare the PAR absorption potential of two competing plant species  

PubMed Central

Mountain pastures dominated by the pasture grass Setaria sphacelata in the Andes of southern Ecuador are heavily infested by southern bracken (Pteridium arachnoideum), a major problem for pasture management. Field observations suggest that bracken might outcompete the grass due to its competitive strength with regard to the absorption of photosynthetically active radiation (PAR). To understand the PAR absorption potential of both species, the aims of the current paper are to (1) parameterize a radiation scheme of a two-big-leaf model by deriving structural (LAI, leaf angle parameter) and optical (leaf albedo, transmittance) plant traits for average individuals from field surveys, (2) to initialize the properly parameterized radiation scheme with realistic global irradiation conditions of the Rio San Francisco Valley in the Andes of southern Ecuador, and (3) to compare the PAR absorption capabilities of both species under typical local weather conditions. Field data show that bracken reveals a slightly higher average leaf area index (LAI) and more horizontally oriented leaves in comparison to Setaria. Spectrometer measurements reveal that bracken and Setaria are characterized by a similar average leaf absorptance. Simulations with the average diurnal course of incoming solar radiation (1998–2005) and the mean leaf–sun geometry reveal that PAR absorption is fairly equal for both species. However, the comparison of typical clear and overcast days show that two parameters, (1) the relation of incoming diffuse and direct irradiance, and (2) the leaf–sun geometry play a major role for PAR absorption in the two-big-leaf approach: Under cloudy sky conditions (mainly diffuse irradiance), PAR absorption is slightly higher for Setaria while under clear sky conditions (mainly direct irradiance), the average bracken individual is characterized by a higher PAR absorption potential. (?74 MJ m?2 year?1). The latter situation which occurs if the maximum daily irradiance exceeds 615 W m?2 is mainly due to the nearly orthogonal incidence of the direct solar beam onto the horizontally oriented frond area which implies a high amount of direct PAR absorption during the noon maximum of direct irradiance. Such situations of solar irradiance favoring a higher PAR absorptance of bracken occur in ?36% of the observation period (1998–2005). By considering the annual course of PAR irradiance in the San Francisco Valley, the clear advantage of bracken on clear days (36% of all days) is completely compensated by the slight but more frequent advantage of Setaria under overcast conditions (64% of all days). This means that neither bracken nor Setaria show a distinct advantage in PAR absorption capability under the current climatic conditions of the study area. PMID:19937454

Silva, Brenner; Roos, Kristin; Gottlicher, Dietrich Otto; Rollenbeck, Rutger; Nauss, Thomas; Beck, Erwin

2009-01-01

343

Design of 118 MHz twelfth harmonic cavity of APS PAR  

SciTech Connect

Two radio frequency (RF) cavities are needed in the Positron Accumulator Ring (PAR) of the Advanced Photon Source. One is for the first harmonic frequency at 9.8 MHz, and the other is for the twelfth harmonic frequency at 118 MHz. This note reports on the design of the 118 MHz RF cavity. Computer models are used to find the mode frequencies, impedances, Q-factors, and field distributions in the cavity. The computer codes MAFIA, URMEL, and URMEL-T are useful tools which model and simulate the resonance characteristics of a cavity. These codes employ the finite difference method to solve Maxwell`s equations. MAFIA is a three-dimensional problem solver and uses square patches to approximate the inner surface of a cavity. URMEL and URMEL-T are two-dimensional problem solvers and use rectangular and triangular meshes, respectively. URMEL-T and MAFIA can handle problems with arbitrary dielectric materials located inside the boundary. The cavity employs a circularly cylindrical ceramic window to limit the vacuum to the beam pipe. The ceramic window used in the modeling will have a wall thickness of 0.9 cm. This wall thickness is not negligible in determining the resonant frequencies of the cavity. In the following, results of two- and three-dimensional modeling of the cavities using the URMEL-T and MAFIA codes are reported.

Kang, Y.W.; Kustom, R.L.; Bridges, J.F.

1992-10-22

344

Nostoc sphaeroides Kütz, a candidate producer par excellence for CELSS  

NASA Astrophysics Data System (ADS)

A lot of aquatic organisms could be regarded as suitable candidates par excellence in the establishment of CELSS, since they are relatively easy and fast to grow and resistant to changes in environmental condition as well as providing nutritious, protein-and vitamin-rich foods for the crew, which can fulfill the main functions of CELSS, including supplying oxygen, water and food, removing carbon dioxide and making daily life waste reusable. Our labotory has developed mass culture of Nostoc sphaeroides Kütz, which is one of traditional healthy food in China and. The oxygen evolution rate of the cyanobacterium is about 150 molO2.mg-1.h-1, and it usually grows into colony with size between 2-20mm, which is easy to be harvested. It also can be cultured with high density, which show that the productivity of the cyanobacterium in limited volume is higher than other microalgae. We had measured the nutrient content of the cyanobacterium and developed some Chinese Dishes and Soups with Nostoc sphaeroides Kütz, which showed that it was a good food for crew. Using remote sensing technique, we also investigated its growth in Closed System under microgravity by SHENZHOU-2 spacecraft in January 2001. We plan to develop suitable bioreactor with the cyanobacterium for supplying oxygen and food to crew in future.

Wang, Gaohong; Hao, Zongjie; Liu, Yongding

345

Pulsed power supply for PAR injection/extraction septum magnet  

SciTech Connect

A 22.5 {mu}H, 22.5 m{Omega} transformer septum magnet must be pulsed at a 60 Hz rate to inject beam from a 450 MeV positron linac into a positron accumulator ring (PAR) and to extract beam from it. Of the 60 pulses per second the first 24 are used for injection and the 30th for extraction. The 25th through the 29th are not used. This pattern is repeated continuously. A design study was performed of the power supply proposed in the APS Title I design. This supply produces a pulse that is approximately a half-sine-wave with a base width of approximately 1/3 ms; its peak current is adjustable from 3.5kA to 4.7kA and is repeatable within {+-}0.05%. The septum steel is reset by a half-sine pulse of reverse polarity a few milliseconds after the forward current pulse. No beam is present during reset. The use of the transformer design minimizes the cost of the capacitors used for energy storage.

McGhee, D.G.

1990-09-23

346

Thse bnficiant du dispositif Jeunes Chercheurs Entrepreneurs (JCE), financ par la Rgion Universit de Bourgogne  

E-print Network

Thèse bénéficiant du dispositif Jeunes Chercheurs Entrepreneurs (JCE), financé par la Région #12;Thèse bénéficiant du dispositif Jeunes Chercheurs Entrepreneurs (JCE), financé par la Région thèse s'est de plus déroulée dans le cadre du dispositif JCE (Jeunes Chercheurs Entrepreneurs) qui vise

Paris-Sud XI, Université de

347

II. DTERMINATION DE LA CONSTANTE DILECTRIQUE STATIQUE PAR DES MTHODES LECTRIQUES.  

E-print Network

to determine the static dielectric constant of cuprous oxide as 03B5s = 7.5 ± 0.15. The measurements were made321. II. D�TERMINATION DE LA CONSTANTE DI�LECTRIQUE STATIQUE PAR DES M�THODES �LECTRIQUES. Par valeur statique de la constante diélectrique (03B5s = 7,5 ± 0,15). Les mesures ont été faites entre 100

Boyer, Edmond

348

QUELQUES PROPRITS LECTROCHIMIQUES DU NIOBIUM par Jacques PAGETTI et Jean TALBOT  

E-print Network

of niobium oxide. Preliminary results have been obtained on the anodic behaviour of niobium in deaerated365 QUELQUES PROPRI�T�S �LECTROCHIMIQUES DU NIOBIUM par Jacques PAGETTI et Jean TALBOT Laboratoire-et-Marie-Curie, Paris 5e Résumé. - Le comportement du niobium dans les solutions acides et alcalines a été étudié par

Paris-Sud XI, Université de

349

Molecular mechanism of bundle formation by the bacterial actin ParM  

SciTech Connect

The actin homolog ParM plays a microtubule-like role in segregating DNA prior to bacterial cell division. Fluorescence and cryo-electron microscopy have shown that ParM forms filament bundles between separating DNA plasmids in vivo. Given the lack of ParM bundling proteins it remains unknown how ParM bundles form at the molecular level. Here we show using time-lapse TIRF microscopy, under in vitro molecular crowding conditions, that ParM-bundle formation consists of two distinct phases. At the onset of polymerization bundle thickness and shape are determined in the form of nuclei of short helically disordered filaments arranged in a liquid-like lattice. These nuclei then undergo an elongation phase whereby they rapidly increase in length. At steady state, ParM bundles fuse into one single large aggregate. This behavior had been predicted by theory but has not been observed for any other cytomotive biopolymer, including F-actin. We employed electron micrographs of ParM rafts, which are 2-D analogs of 3-D bundles, to identify the main molecular interfilament contacts within these suprastructures. The interface between filaments is similar for both parallel and anti-parallel orientations and the distribution of filament polarity is random within a bundle. We suggest that the interfilament interactions are not due to the interactions of specific residues but rather to long-range, counter ion mediated, electrostatic attractive forces. A randomly oriented bundle ensures that the assembly is rigid and that DNA may be captured with equal efficiency at both ends of the bundle via the ParR binding protein.

Popp, David, E-mail: dpopp@imcb.a-star.edu.sg [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore); Narita, Akihiro [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Iwasa, Mitsusada [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Maeda, Yuichiro [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [ERATO 'Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Robinson, Robert C. [Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore)] [Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore)

2010-01-22

350

Une mthode de Branch and Bound par Intervalles applique la rsolution en vitesse de conflits ariens  

E-print Network

Une méthode de Branch and Bound par Intervalles appliquée à la résolution en vitesse de conflits Narbonne, F-31062 Toulouse Cedex 9, France Mots-Clés : IBBA, résolution de conflits 1 Introduction Deux avions en croisière à la même altitude séparés de moins de 5 miles nautiques sont dits en conflit. Le

Boyer, Edmond

351

uPA and uPAR in fibrinolysis, immunity and pathology  

Microsoft Academic Search

The urokinase plasminogen activator (uPA) and its receptor (uPAR) exert pleiotropic functions over the course of both physiological and pathological processes. Data generated in deficient mice have underlined how uPA not only has a key role in fibrinolysis but also modulates the development of protective immunity. By contrast, uPAR anchors uPA at the cell surface and, in addition to favoring

Anna Mondino; Francesco Blasi

2004-01-01

352

ALERTEES PAR LA MORT CELLULAIRE, NOS DEFENSES ANTIVIRALES METTENT LE TURBO  

E-print Network

MORT CELLULAIRE, NOS DEFENSES ANTIVIRALES METTENT LE TURBO Genève, le 9 février 2012 SOUS EMBARGO JUSQU marche après que certaines cellules ont été détruites par l'ennemi viral. A leur mort, elles relâchent associated molecular pattern). Ces DAMP se distinguent du reste des débris de la cellule morte par leur

Loewith, Robbie

353

Comptes Rendus des JNC 17 -Poitiers 2011 Prdiction du comportement viscolastique de matriaux composites textiles par  

E-print Network

composites textiles par une approche d'homogénéisation Prediction of the viscoelastic behaviour of textile'homogénéisation analytiques et numériques afin d'évaluer le comportement effectif de matériaux composites textiles fibres textiles par des inclusions ellipsoïdales, dont la solution théorique est connue. Dans cette

Paris-Sud XI, Université de

354

TUDE MICROGRAPHIQUE ET MCANIQUE DES ACIERS AU NICKEL ; Par M. LON GUILLET (1).  

E-print Network

ou l'acide picrique, mais est fortement coloré par le picrate de soude (1) ; La perlite, qui est l colorée en noir par l'acide picrique, etc... Les aciers recuits sont constitués de ferrite et perlite, quand ils contiennent moins de 0,900 ~; 0 de carbone ; de perlite et de cérnentite, lorsqu

Paris-Sud XI, Université de

355

Mesure de la digestibilit des fourrages destins aux chevaux par la technique des sacs de nylon  

E-print Network

Mesure de la digestibilité des fourrages destinés aux chevaux par la technique des sacs de nylon selle adultes et par la technique des sacs de nylon sur 2 poneys mâles, adultes, munis d'une canule heures selon la méthode de TILLEY et TERRY (1963), puis le sac est introduit dans le caecum pour une

Boyer, Edmond

356

EFFETS DES DGNRESCENCES ZEEMAN SUR LA FLUORESCENCE DE RSONANCE INDUITE PAR UN LASER INTENSE  

E-print Network

L-173 EFFETS DES D�G�N�RESCENCES ZEEMAN SUR LA FLUORESCENCE DE R�SONANCE INDUITE PAR UN LASER Zeeman des niveaux inférieur et supérieur d'une transition atomique saturée par un laser résonnant. 2014 Some consequences of the Zeeman degeneracy of the lower and upper states of an atomic transition

Boyer, Edmond

357

L'EFFET ZEEMAN DES RAIES MULTIPOLAIRES EN THORIE CLASSIQUE DU RAYONNEMENT Par MILE DURAND.  

E-print Network

L'EFFET ZEEMAN DES RAIES MULTIPOLAIRES EN TH�ORIE CLASSIQUE DU RAYONNEMENT Par �MILE DURAND x3.)on a écrit d4 ou x- au lieu de '- -; 'r = X4 - X3')* 4 c t " "" On peut en déduire le champ électrique E,, (vecteur de Fresnel de l'onde lumineuse) par les formules habituelles :-. Comme avec on en

Paris-Sud XI, Université de

358

SUR LE RAYONNEMENT K DU BORE Par A. HAUTOT et J. SERPE.  

E-print Network

SUR LE RAYONNEMENT K DU BORE Par A. HAUTOT et J. SERPE. lnstitut de Physique de l'Université de Liège. Sommaire. 2014 Les auteurs ont étudié la structure du rayonnement K émis par le bore à l'état d avec la température à laquelle le bore est porté. L'étude a porté aussi sur deux composés du bore

Boyer, Edmond

359

MESURE D'UN CHAMP LECTRIQUE HYPERFRQUENCE PAR RSONANCE ROTATOIRE DE L'OXYDE NITRIQUE  

E-print Network

803. MESURE D'UN CHAMP �LECTRIQUE HYPERFR�QUENCE PAR R�SONANCE ROTATOIRE DE L'OXYDE NITRIQUE Par dipolaires électriques entre niveaux Zeeman de l'oxyde nitrique NO placé dans un champ magnétique. On établit levels of nitric oxyde submitted to a static magnetic field. We derive the condition of rotary resonance

Boyer, Edmond

360

INTERRUPTEUR A MERCURE POUR LES FORTES BOBINES DE RUHMKORFF ; Par MM. E. DUCRETET et L. LEJEUNE.  

E-print Network

336 INTERRUPTEUR A MERCURE POUR LES FORTES BOBINES DE RUHMKORFF ; Par MM. E. DUCRETET et L. LEJEUNE étroite et les dimensions restreintes don- nées généralement au godet contenant le mercure et l ceux décrits par MM. Gordon et Londe. Le mercure est contenu dans la partie étroite du godet 10 à i5

Paris-Sud XI, Université de

361

SUR LES SPECTRES ULTRAVIOLETS MIS PAR UN MLANGE D'HYDROGNE ET DE VAPEUR DE MERCURE  

E-print Network

SUR LES SPECTRES ULTRAVIOLETS �MIS PAR UN M�LANGE D'HYDROG�NE ET DE VAPEUR DE MERCURE par M. HENRYK évidence un nouveau système de bandes ultraviolettes de l'hydrure de mercure. Ces bandes ont été soumises à'hydrure de mercure de Hulthén. De mème, le sens de la dégradation de nouvelles bandes est inverse. On peut

Paris-Sud XI, Université de

362

MISSION CATHODIQUE A L'INTRIEUR DES LAMPES A INCANDESCENCE ; par M. L. HOULLEVIGUE (1).  

E-print Network

'ampoule. Cette lueur, examinée au spectroscope, donne les raies du mercure; elle disparait spontanément au bout charbon, qui rendent lumineuse par leurs chocs la vapeur du mercure laissée dans l'ampoule par la pompe à vapeur de mercure et la rendre lumineuse. Il On observe des apparences plus faciles à interpréter en

Boyer, Edmond

363

Recruitment of the ParG Segregation Protein to Different Affinity DNA Sites? §  

PubMed Central

The segrosome is the nucleoprotein complex that mediates accurate plasmid segregation. In addition to its multifunctional role in segrosome assembly, the ParG protein of multiresistance plasmid TP228 is a transcriptional repressor of the parFG partition genes. ParG is a homodimeric DNA binding protein, with C-terminal regions that interlock into a ribbon-helix-helix fold. Antiparallel ?-strands in this fold are presumed to insert into the OF operator major groove to exert transcriptional control as established for other ribbon-helix-helix factors. The OF locus comprises eight degenerate tetramer boxes arranged in a combination of direct and inverted orientation. Each tetramer motif likely recruits one ParG dimer, implying that the fully bound operator is cooperatively coated by up to eight dimers. OF was subdivided experimentally into four overlapping 20-bp sites (A to D), each of which comprises two tetramer boxes separated by AT-rich spacers. Extensive interaction studies demonstrated that sites A to D individually are bound with different affinities by ParG (C > A ? B ? D). Moreover, comprehensive scanning mutagenesis revealed the contribution of each position in the site core and flanking sequences to ParG binding. Natural variations in the tetramer box motifs and in the interbox spacers, as well as in flanking sequences, each influence ParG binding. The OF operator apparently has evolved with sites that bind ParG dissimilarly to produce a nucleoprotein complex fine-tuned for optimal interaction with the transcription machinery. The association of other ribbon-helix-helix proteins with complex recognition sites similarly may be modulated by natural sequence variations between subsites. PMID:19376860

Zampini, Massimiliano; Derome, Andrew; Bailey, Simon E. S.; Barilla, Daniela; Hayes, Finbarr

2009-01-01

364

Recruitment of the ParG segregation protein to different affinity DNA sites.  

PubMed

The segrosome is the nucleoprotein complex that mediates accurate plasmid segregation. In addition to its multifunctional role in segrosome assembly, the ParG protein of multiresistance plasmid TP228 is a transcriptional repressor of the parFG partition genes. ParG is a homodimeric DNA binding protein, with C-terminal regions that interlock into a ribbon-helix-helix fold. Antiparallel beta-strands in this fold are presumed to insert into the O(F) operator major groove to exert transcriptional control as established for other ribbon-helix-helix factors. The O(F) locus comprises eight degenerate tetramer boxes arranged in a combination of direct and inverted orientation. Each tetramer motif likely recruits one ParG dimer, implying that the fully bound operator is cooperatively coated by up to eight dimers. O(F) was subdivided experimentally into four overlapping 20-bp sites (A to D), each of which comprises two tetramer boxes separated by AT-rich spacers. Extensive interaction studies demonstrated that sites A to D individually are bound with different affinities by ParG (C > A approximately B > D). Moreover, comprehensive scanning mutagenesis revealed the contribution of each position in the site core and flanking sequences to ParG binding. Natural variations in the tetramer box motifs and in the interbox spacers, as well as in flanking sequences, each influence ParG binding. The O(F) operator apparently has evolved with sites that bind ParG dissimilarly to produce a nucleoprotein complex fine-tuned for optimal interaction with the transcription machinery. The association of other ribbon-helix-helix proteins with complex recognition sites similarly may be modulated by natural sequence variations between subsites. PMID:19376860

Zampini, Massimiliano; Derome, Andrew; Bailey, Simon E S; Barillà, Daniela; Hayes, Finbarr

2009-06-01

365

Absorption du rayonnement 12 et 8 millimtres par les vapeurs de propane sous pression  

E-print Network

Absorption du rayonnement 12 et 8 millimètres par les vapeurs de propane sous pression A. Battaglia des pertes diélectriques (03B5") présentées par le propane gazeux aux fréquences de 24 et 36 GHz, à la Birnbaum. Abstract. 2014 Experimental study of dielectric losses (03B5") presented by gaseous propane

Boyer, Edmond

366

LES RSEAUX DE DRAINAGE SUPERFICIEL ET LEUR COLONISATION PAR LYMNAEA TRUNCATULA MLLER.  

E-print Network

LES R�SEAUX DE DRAINAGE SUPERFICIEL ET LEUR COLONISATION PAR LYMNAEA TRUNCATULA M�LLER. A PROPOS DE. drainage par le mollusque et de déterminer les conséquences au niveau du peuplement lim- néen ; - de prairie occupe le fond d'un vallon et présente un réseau de drainage super- ficiel disposé en épi et

Boyer, Edmond

367

Slmb antagonises the aPKC/Par-6 complex to control oocyte and epithelial polarity  

PubMed Central

The Drosophila anterior-posterior axis is specified when the posterior follicle cells signal to polarise the oocyte, leading to the anterior/lateral localisation of the Par-6/aPKC complex and the posterior recruitment of Par-1, which induces a microtubule reorganisation that localises bicoid and oskar mRNAs. Here we show that oocyte polarity requires Slmb, the substrate specificity subunit of the SCF E3 ubiquitin ligase that targets proteins for degradation. The Par-6/aPKC complex is ectopically localised to the posterior of slmb mutant oocytes, and Par-1 and oskar mRNA are mislocalised. Slmb appears to play a related role in epithelial follicle cells, as large slmb mutant clones disrupt epithelial organisation, whereas small clones show an expansion of the apical domain, with increased accumulation of apical polarity factors at the apical cortex. The levels of aPKC and Par-6 are significantly increased in slmb mutants, whereas Baz is slightly reduced. Thus, Slmb may induce the polarisation of the anterior-posterior axis of the oocyte by targeting the Par-6/aPKC complex for degradation at the oocyte posterior. Consistent with this, overexpression of the aPKC antagonist Lgl strongly rescues the polarity defects of slmb mutant germline clones. The role of Slmb in oocyte polarity raises an intriguing parallel with C. elegans axis formation, in which PAR-2 excludes the anterior PAR complex from the posterior cortex to induce polarity, but its function can be substituted by overexpressing Lgl. PMID:25053432

Morais-de-Sa, Eurico; Mukherjee, Avik; Lowe, Nick; St Johnston, Daniel

2014-01-01

368

TOXINES D'ASPERGILLUS OCHRACEUS WILHELM PRODUCTION D'OCHPATOXINES PAR DES SOUCHES ISOLES  

E-print Network

; deux sécrètent à la fois l'ochratoxine A et l'ochratoxine B ; par contre, ni la melléine, ni l ochratoxines A et B. #12;Isolées et identifiées par VAN DER MERWE (1965), les ochratoxines A et B ont fait l'objet de travaux portant sur leur étude physico-chimique, biochimique et toxi- cologique. L'ochratoxine

Paris-Sud XI, Université de

369

BRUCELLOSE BOVINE EXPRIMENTALE INFECTION PAR BRUCELLA ABORTUS DES VEAUX A LA NAISSANCE  

E-print Network

BRUCELLOSE BOVINE EXP�RIMENTALE VI. - INFECTION PAR « BRUCELLA ABORTUS » DES VEAUX A LA NAISSANCE A diagnostic bact6riologique de brucellose, la mise en culture de colostrum et du mucus vaginal est pr6f6r6e,OMMET, 1970 b), de colostrums et de laits (PHII,IPPON, RENOUX et PLOMMET, 1971). (I,es velles, séparées de

Boyer, Edmond

370

Engineering Thrombin for Selective Specificity toward Protein C and PAR1*  

PubMed Central

Thrombin elicits functional responses critical to blood homeostasis by interacting with diverse physiological substrates. Ala-scanning mutagenesis of 97 residues covering 53% of the solvent accessible surface area of the enzyme identifies Trp215 as the single most important determinant of thrombin specificity. Saturation mutagenesis of Trp215 produces constructs featuring kcat/Km values for the hydrolysis of fibrinogen, protease-activated receptor PAR1, and protein C that span five orders of magnitude. Importantly, the effect of Trp215 replacement is context dependent. Mutant W215E is 10-fold more specific for protein C than fibrinogen and PAR1, which represents a striking shift in specificity relative to wild-type that is 100-fold more specific for fibrinogen and PAR1 than protein C. However, when the W215E mutation is combined with deletion of nine residues in the autolysis loop, which by itself shifts the specificity of the enzyme from fibrinogen and PAR1 to protein C, the resulting construct features significant activity only toward PAR1. These findings demonstrate that thrombin can be re-engineered for selective specificity toward protein C and PAR1. Mutations of Trp215 provide important reagents for dissecting the multiple functional roles of thrombin in the blood and for clinical applications. PMID:20404340

Marino, Francesca; Pelc, Leslie A.; Vogt, Austin; Gandhi, Prafull S.; Di Cera, Enrico

2010-01-01

371

THE PRO-APOPTOTIC PROTEIN PAR-4 FACILITATES VASCULAR CONTRACTILITY BY CYTOSKELETAL TARGETING OF ZIPK  

PubMed Central

Par-4 (prostate apoptosis response 4) is a pro-apoptotic protein and tumor suppressor that was originally identified as a gene product upregulated during apoptosis in prostate cancer cells. Here, we show, for the first time, that Par-4 is expressed and co-localizes with the actin filament bundles in vascular smooth muscle. Furthermore, we demonstrate that targeting of ZIPK to the actin filaments, as observed upon PGF-2 alpha stimulation, is inhibited by the presence of a cell permeant Par-4 decoy peptide. The same decoy peptide also significantly inhibits PGF-2 alpha induced contractions of smooth muscle tissue. Moreover, knockdown of Par-4 using antisense morpholino nucleotides results in significantly reduced contractility, and myosin light chain and myosin phosphatase target subunit phosphorylation. These results indicate that Par-4 facilitates contraction by targeting ZIPK to the vicinity of its substrates, myosin light chain and MYPT, which are located on the actin filaments. These results identify Par-4 as a novel regulator of myosin light chain phosphorylation in differentiated, contractile vascular smooth muscle. PMID:18505470

Vetterkind, Susanne; Morgan, Kathleen G.

2009-01-01

372

Examining relational empowerment for elementary school students in a yPAR program.  

PubMed

This paper joins relational empowerment, youth empowerment, and Bridging Multiple Worlds frameworks to examine forms of relational empowerment for children in two intermediary institutions-school and a youth participatory action research after-school program (yPAR ASP). Participants were twelve children, most of whom were Latina/o and from im/migrant families, enrolled in a yPAR ASP for 2 years. A mixed-method approach was utilized; we analyzed children's interviews, self-defined goals, and their social networks to examine their experiences of relational empowerment. We conclude that children experienced each of the five relational empowerment factors-collaborative competence, bridging social divisions, facilitating others' empowerment, mobilizing networks, and passing on a legacy-in the yPAR ASP setting, and some factors in school. These experiences, however, were more pronounced in the yPAR ASP setting. Additionally, social network analyses revealed that a small but meaningful percentage of actors bridged worlds, especially home and family, but by year 2, also school and the yPAR ASP. Finally, most helpers for school-based goals came from school, but a sizable number came from family, friends, and home worlds, and by year 2, also came from the yPAR ASP. Implications range from theoretical to methodological development, including the use of social network analysis as a tool to descriptively examine relational power in context. PMID:24356900

Langhout, Regina Day; Collins, Charles; Ellison, Erin Rose

2014-06-01

373

Sphingosine-1-phosphate induces thrombin receptor PAR-4 expression to enhance cell migration and COX-2 formation in human monocytes.  

PubMed

Thrombin is not only a central factor in blood coagulation but also stimulates inflammatory processes, including monocyte responses, via activation of PARs. The signaling lipid S1P is a major determinant of monocyte function. Here, we established an interaction between S1P and human monocyte responses to thrombin. S1P induced PAR-1 and PAR-4 mRNA and total protein expression in human monocytes and U937 cells in a concentration (0.1-10 ?M)- and time (1-24 h)-dependent manner, respectively. However, only PAR-4 cell-surface expression was increased significantly by S1P, whereas PAR-1 remained unaffected. This response was associated with activation of the Akt, Erk, and p38 pathway and induction of COX-2 but not COX-1. PAR-4-mediated induction of COX-2 was prevented by the PI3K inhibitor LY (10 ?M). Preincubation of human monocytes with S1P (1 ?M; 16 h) resulted in an enhanced chemotaxis toward thrombin or to selective AP for PAR-4 but not PAR-1. Furthermore, down-regulation of PAR-4 transcription with siRNA attenuated the chemotactic response to thrombin and AP4. In conclusion, S1P enhances monocyte responses to thrombin via up-regulation of PAR-4 expression, which promotes cell migration and COX-2 abundance. This mechanism may facilitate monocyte recruitment to sites of vessel injury and inflammation. PMID:24990321

Mahajan-Thakur, Shailaja; Sostmann, Björn D; Fender, Anke C; Behrendt, Daniel; Felix, Stephan B; Schrör, Karsten; Rauch, Bernhard H

2014-10-01

374

PAR-2, IL-4R, TGF-? and TNF-? in bronchoalveolar lavage distinguishes extrinsic allergic alveolitis from sarcoidosis  

PubMed Central

Sarcoidosis (SARC) and extrinsic allergic alveolitis (EAA) share certain markers, making a differential diagnosis difficult even with histopathological investigation. In lung tissue, proteinase-activated receptor-2 (PAR-2) is primarily investigated with regard to epithelial and inflammatory perspectives. Varying levels of certain chemokines can be a useful tool for distinguishing EAA and SARC. Thus, in the present study, differences in the levels of transforming growth factor (TGF)-?1, tumor necrosis factor (TNF)-?, interleukin-4 receptor (IL-4R) and PAR-2 in bronchoalveolar lavage fluid (BALF) were compared, using an ELISA method, between 14 patients with EAA and six patients with SARC. Statistically significant higher levels of IL-4R, PAR-2 and the PAR-2/TGF-?1 and PAR-2/TNF-? ratios were observed in EAA patients as compared with SARC patients. Furthermore, the ratios of TNF-?/total protein, TGF-?1/PAR-2 and TNF-?/PAR-2 were significantly lower in EAA patients than in SARC patients. The results indicated a higher detection of PAR-2 in EAA samples in association with TNF-? and TGF-? levels. As EAA and PAR-2 in parallel belong to the Th2-mediated pathway, the results significantly indicated an association between this receptor and etiology. In addition, the results indicated that SARC is predominantly a granulomatous inflammatory disease, thus, higher levels of TNF-? are observed. Therefore, the detection of PAR-2 and investigated chemokines in BALF may serve as a useful tool in the differential diagnosis between EAA and SARC. PMID:25009615

MATEJ, RADOSLAV; SMETAKOVA, MAGDALENA; VASAKOVA, MARTINA; NOVAKOVA, JANA; STERCLOVA, MARTINA; KUKAL, JAROMIR; OLEJAR, TOMAS

2014-01-01

375

Uncoupling of Nucleotide Hydrolysis and Polymerization in the ParA Protein Superfamily Disrupts DNA Segregation Dynamics*  

PubMed Central

DNA segregation in bacteria is mediated most frequently by proteins of the ParA superfamily that transport DNA molecules attached via the segrosome nucleoprotein complex. Segregation is governed by a cycle of ATP-induced polymerization and subsequent depolymerization of the ParA factor. Here, we establish that hyperactive ATPase variants of the ParA homolog ParF display altered segrosome dynamics that block accurate DNA segregation. An arginine finger-like motif in the ParG centromere-binding factor augments ParF ATPase activity but is ineffective in stimulating nucleotide hydrolysis by the hyperactive proteins. Moreover, whereas polymerization of wild-type ParF is accelerated by ATP and inhibited by ADP, filamentation of the mutated proteins is blocked indiscriminately by nucleotides. The mutations affect a triplet of conserved residues that are situated neither in canonical nucleotide binding and hydrolysis motifs in the ParF tertiary structure nor at interfaces implicated in ParF polymerization. Instead the residues are involved in shaping the contours of the binding pocket so that nucleotide binding locks the mutant proteins into a configuration that is refractory to polymerization. Thus, the architecture of the pocket not only is crucial for optimal ATPase kinetics but also plays a key role in the polymerization dynamics of ParA proteins that drive DNA segregation ubiquitously in procaryotes. PMID:23093445

Dobruk-Serkowska, Aneta; Caccamo, Marisa; Rodriguez-Castaneda, Fernando; Wu, Meiyi; Bryce, Kerstyn; Ng, Irene; Schumacher, Maria A.; Barilla, Daniela; Hayes, Finbarr

2012-01-01

376

Uncoupling of nucleotide hydrolysis and polymerization in the ParA protein superfamily disrupts DNA segregation dynamics.  

PubMed

DNA segregation in bacteria is mediated most frequently by proteins of the ParA superfamily that transport DNA molecules attached via the segrosome nucleoprotein complex. Segregation is governed by a cycle of ATP-induced polymerization and subsequent depolymerization of the ParA factor. Here, we establish that hyperactive ATPase variants of the ParA homolog ParF display altered segrosome dynamics that block accurate DNA segregation. An arginine finger-like motif in the ParG centromere-binding factor augments ParF ATPase activity but is ineffective in stimulating nucleotide hydrolysis by the hyperactive proteins. Moreover, whereas polymerization of wild-type ParF is accelerated by ATP and inhibited by ADP, filamentation of the mutated proteins is blocked indiscriminately by nucleotides. The mutations affect a triplet of conserved residues that are situated neither in canonical nucleotide binding and hydrolysis motifs in the ParF tertiary structure nor at interfaces implicated in ParF polymerization. Instead the residues are involved in shaping the contours of the binding pocket so that nucleotide binding locks the mutant proteins into a configuration that is refractory to polymerization. Thus, the architecture of the pocket not only is crucial for optimal ATPase kinetics but also plays a key role in the polymerization dynamics of ParA proteins that drive DNA segregation ubiquitously in procaryotes. PMID:23093445

Dobruk-Serkowska, Aneta; Caccamo, Marisa; Rodríguez-Castañeda, Fernando; Wu, Meiyi; Bryce, Kerstyn; Ng, Irene; Schumacher, Maria A; Barillà, Daniela; Hayes, Finbarr

2012-12-14

377

A novel isoform of prostate apoptosis response 4 (PAR-4) that co-distributes with F-actin and prevents apoptosis in neural stem cells.  

PubMed

The elevated expression of prostate apoptosis response-4 (PAR-4) induces apoptosis in differentiating mouse embryonic stem (ES) cells. In embryoid body (EB) cells and the E15.5 stage of embryonic mouse brain, PAR-4 is expressed as two isoforms (38 and 33 kDa). Using mouse EB-derived RNA as a template we have cloned and characterized a novel isoform of PAR-4 (PAR-4/p33) that lacks exon 3 and shows a bona fide splice junction of exons 2 and 4. The molecular mass for PAR-4/p33 is estimated to be 33 kDa, corresponding to the short form found in the EB cells and E15.5 mouse brain. The fluorescent fusion protein of PAR-4/p33 is mainly found in the cytosol and is co-distributed with F-actin filaments, while that of the 38 kDa full length PAR-4/p38 is predominantly translocated to the nucleus. In contrast to the full length PAR-4 (PAR-4/p38), ectopic expression of PAR-4/p33 does not result in the activation of caspase 3 and the induction of apoptosis. PAR-4/p33 forms a complex with PAR-4/p38, which inhibits its nuclear translocation and the induction of apoptosis. PAR-4/p33 is suggested to be a dominant negative isoform of PAR-4/p38 and may regulate PAR-4-dependent apoptosis. PMID:16520897

Wang, G; Silva, J; Krishnamurthy, K; Bieberich, E

2006-03-01

378

Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells  

NASA Astrophysics Data System (ADS)

Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr32922d

Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm; Iversen, Frank; Liu, Zhuo; Thomsen, Karen; Pedersen, Michael; Skrydstrup, Troels; Nielsen, Niels Chr.; Ploug, Michael; Kjems, Jørgen

2013-08-01

379

Efficacy and safety of the pars plana clip in the Ahmed valve device inserted via the pars plana in patients with refractory glaucoma  

PubMed Central

Purpose: To evaluate the efficacy and safety of the pars plana clip (PPC) in the Ahmed valve tube inserted via the pars plana in patients with secondary refractory glaucomas. Methods: Prospective and interventional case series that included 10 patients with secondary refractory glaucoma. The pars plana vitrectomy and the implant of the modified tube were performed during the same surgery. Control of intraocular pressure (IOP) and the development of intra- and postoperative complications were evaluated during the follow-up. Results: Follow-up time was twelve months in all the patients. Control of IOP was achieved in 90% of patients, and 70% needed no antiglaucoma treatment. The complications that occurred were transient hypotony in three cases, choroidal detachment in two cases, and one case of intraocular hemorrhage. No case of tube extrusion or tube kink was observed. Conclusions: Our data suggests that implantation of the Ahmed tube modified with the PPC via the pars plana is safe and effective in patients with secondary refractory glaucomas. PMID:20463912

Diaz-Llopis, Manuel; Salom, David; Garcia-Delpech, Salvador; Udaondo, Patricia; Millan, Jose Maria; Arevalo, J Fernando

2010-01-01

380

Identification of a New Epitope in uPAR as a Target for the Cancer Therapeutic Monoclonal Antibody ATN-658, a Structural Homolog of the uPAR Binding Integrin CD11b (?M)  

PubMed Central

The urokinase plasminogen activator receptor (uPAR) plays a role in tumor progression and has been proposed as a target for the treatment of cancer. We recently described the development of a novel humanized monoclonal antibody that targets uPAR and has anti-tumor activity in multiple xenograft animal tumor models. This antibody, ATN-658, does not inhibit ligand binding (i.e. uPA and vitronectin) to uPAR and its mechanism of action remains unclear. As a first step in understanding the anti-tumor activity of ATN-658, we set out to identify the epitope on uPAR to which ATN-658 binds. Guided by comparisons between primate and human uPAR, epitope mapping studies were performed using several orthogonal techniques. Systematic site directed and alanine scanning mutagenesis identified the region of aa 268–275 of uPAR as the epitope for ATN-658. No known function has previously been attributed to this epitope Structural insights into epitope recognition were obtained from structural studies of the Fab fragment of ATN-658 bound to uPAR. The structure shows that the ATN-658 binds to the DIII domain of uPAR, close to the C-terminus of the receptor, corroborating the epitope mapping results. Intriguingly, when bound to uPAR, the complementarity determining region (CDR) regions of ATN-658 closely mimic the binding regions of the integrin CD11b (?M), a previously identified uPAR ligand thought to be involved in leukocyte rolling, migration and complement fixation with no known role in tumor progression of solid tumors. These studies reveal a new functional epitope on uPAR involved in tumor progression and demonstrate a previously unrecognized strategy for the therapeutic targeting of uPAR. PMID:24465541

Wei, Ying; Donate, Fernando; Juarez, Jose; Parry, Graham; Chen, Liqing; Meehan, Edward J.; Ahn, Richard W.; Ugolkov, Andrey; Dubrovskyi, Oleksii; O'Halloran, Thomas V.; Huang, Mingdong; Mazar, Andrew P.

2014-01-01

381

An activated protein C analog stimulates neuronal production by human neural progenitor cells via a PAR1-PAR3-S1PR1-Akt pathway  

PubMed Central

Activated protein C (APC) is a protease with anticoagulant and cell-signaling activities. In the central nervous system, APC and its analogs with reduced anticoagulant activity but preserved cell signaling activities, such as 3K3A-APC, exert neuroprotective, vasculoprotective and anti-inflammatory effects. Murine APC promotes subependymal neurogenesis in rodents in vivo after ischemic and traumatic brain injury. Whether human APC can influence neuronal production from resident progenitor cells in humans is unknown. Here we show that 3K3A-APC, but not S360A-APC (an enzymatically inactive analog of APC), stimulated neuronal mitogenesis and differentiation from fetal human neural stem and progenitor cells (NPCs). 3K3A-APC’s effects on proliferation and differentiation were comparable to those respectively obtained with fibroblast growth factor and brain-derived growth factor. Its promoting effect on neuronal differentiation was accompanied by inhibition of astroglial differentiation. In addition, 3K3A-APC exerted modest anti-apoptotic effects during neuronal production. These effects appeared mediated through specific protease activated (PAR) and sphingosine-1-phosphate (S1PR) receptors, in that siRNA-mediated inhibition of PARs 1–4 and S1PRs 1–5 revealed that PAR1, PAR3 and S1PR1 are required for the neurogenic effects of 3K3A-APC. 3K3A-APC activated Akt, a downstream target of S1PR1, which was inhibited by S1PR1, PAR1 and PAR3 silencing. Adenoviral transduction of NPCs with a kinase-defective Akt mutant abolished the effects of 3K3A-APC on NPCs, confirming a key role of Akt activation in 3K3A-APC-mediated neurogenesis. Thus, APC and its pharmacological analogues, by influencing PAR and S1PR signals in resident neural progenitor cells, may be potent modulators of both development and repair in the human CNS. PMID:23554499

Guo, Huang; Zhao, Zhen; Yang, Qi; Wang, Min; Bell, Robert D.; Wang, Su; Chow, Nienwen; Davis, Thomas P.; Griffin, John H.; Goldman, Steven A.; Zlokovic, Berislav V.

2013-01-01

382

An activated protein C analog stimulates neuronal production by human neural progenitor cells via a PAR1-PAR3-S1PR1-Akt pathway.  

PubMed

Activated protein C (APC) is a protease with anticoagulant and cell-signaling activities. In the CNS, APC and its analogs with reduced anticoagulant activity but preserved cell signaling activities, such as 3K3A-APC, exert neuroprotective, vasculoprotective, and anti-inflammatory effects. Murine APC promotes subependymal neurogenesis in rodents in vivo after ischemic and traumatic brain injury. Whether human APC can influence neuronal production from resident progenitor cells in humans is unknown. Here we show that 3K3A-APC, but not S360A-APC (an enzymatically inactive analog of APC), stimulates neuronal mitogenesis and differentiation from fetal human neural stem and progenitor cells (NPCs). The effects of 3K3A-APC on proliferation and differentiation were comparable to those obtained with fibroblast growth factor and brain-derived growth factor, respectively. Its promoting effect on neuronal differentiation was accompanied by inhibition of astroglial differentiation. In addition, 3K3A-APC exerted modest anti-apoptotic effects during neuronal production. These effects appeared to be mediated through specific protease activated receptors (PARs) and sphingosine-1-phosphate receptors (S1PRs), in that siRNA-mediated inhibition of PARs 1-4 and S1PRs 1-5 revealed that PAR1, PAR3, and S1PR1 are required for the neurogenic effects of 3K3A-APC. 3K3A-APC activated Akt, a downstream target of S1PR1, which was inhibited by S1PR1, PAR1, and PAR3 silencing. Adenoviral transduction of NPCs with a kinase-defective Akt mutant abolished the effects of 3K3A-APC on NPCs, confirming a key role of Akt activation in 3K3A-APC-mediated neurogenesis. Therefore, APC and its pharmacological analogs, by influencing PAR and S1PR signals in resident neural progenitor cells, may be potent modulators of both development and repair in the human CNS. PMID:23554499

Guo, Huang; Zhao, Zhen; Yang, Qi; Wang, Min; Bell, Robert D; Wang, Su; Chow, Nienwen; Davis, Thomas P; Griffin, John H; Goldman, Steven A; Zlokovic, Berislav V

2013-04-01

383

Detecting Plant Photoprotective Response to Water Stress Through Variation In PAR Reflectance  

NASA Astrophysics Data System (ADS)

Published papers over several decades have shown increasing leaf-level optical reflectance with decreasing leaf water content. Our experimental results using maize and sorghum showed this increase consistently, caused by variation in optical absorption, in the visible (photosynthetically active radiation - PAR) and middle infrared (MIR) spectral regions. Relatively smaller response, driven by variation in optical scatter, was observed in near infrared (NIR). The concomitant increasing reflectance in the PAR and MIR regions is perplexing. PAR reflectance is dominated by chlorophyll absorption while MIR reflectance is dominated by water molecule absorption. However, changes in chlorophyll concentration, determined by chemical extraction, were too small to account for the variation in PAR reflectance. PAR and MIR reflectances were also influenced by the strength of incident light. Hence PAR reflectance appears to be modulated not only by pigment concentration, the classical description, but also by the strength of incident light and the severity of water deficit. We previously reported that these findings were consistent with chloroplast avoidance movement, a plant photoprotective response, which limits light absorption by pigments. We report here our continuing investigation of this phenomenon. In addition to reflectance measurements, time-lapse microscope images of leaves under increasing water deficit conditions were obtained. These show a brightening between veins which strongly supports our assertion that changes in PAR reflectance accompanying water deficit are caused primarily by chloroplast avoidance movement. Our results suggest that leaf, and possibly canopy, reflectance can therefore be used to detect and measure plant stress. These results also indicate that chloroplast avoidance movement may cause poor estimates of leaf chlorophyll content using techniques based on fluoresced, reflected or transmitted light.

Zygielbaum, A. I.; Arkebauer, T. J.; Walter-Shea, E.

2012-12-01

384

Profiling Gene Expression Induced by Protease-Activated Receptor 2 (PAR2) Activation in Human Kidney Cells  

Microsoft Academic Search

Protease-Activated Receptor-2 (PAR2) has been implicated through genetic knockout mice with cytokine regulation and arthritis development. Many studies have associated PAR2 with inflammatory conditions (arthritis, airways inflammation, IBD) and key events in tumor progression (angiogenesis, metastasis), but they have relied heavily on the use of single agonists to identify physiological roles for PAR2. However such probes are now known not

Jacky Y. Suen; Brooke Gardiner; Sean Grimmond; David P. Fairlie; Xiaolin Wu

2010-01-01

385

Soluble urokinase receptor (uPAR, CD 87) is present in serum and cerebrospinal fluid in patients with neurologic diseases  

Microsoft Academic Search

Background: The receptor for urokinase plasminogen activator (uPAR) promotes invasion by neoplastic or inflammatory cells by focusing proteolysis of urokinase to the cell surface. In pathologic conditions, soluble forms of the receptor (suPAR) are released, and activate cell receptors to promote chemotaxis. In the CNS, suPAR and other components of the plasminogen activation system (PAS) could be associated with an

Juan Carlos Garcia-Monco; James L Coleman; Jorge L Benach

2002-01-01

386

Urokinase-type plasminogen activator receptor (uPAR) augments brain damage in a murine model of ischemic stroke  

Microsoft Academic Search

Urokinase-type plasminogen activator receptor (uPAR) is a key component of the plasminogen activation system at the cell surface. Recent studies showed that uPAR is expressed in the ischemic damaged brain, suggesting its involvement in brain damage. In this study, we evaluated the role of uPAR in ischemic brain damage induced by permanent middle cerebral artery (MCA) occlusion in mice with

Nobuo Nagai; Kiyotaka Okada; Naoyuki Kawao; Chikako Ishida; Shigeru Ueshima; Desire Collen; Osamu Matsuo

2008-01-01

387

Inhibition of in vivo tumorigenicity and invasiveness of a human glioblastoma cell line transfected with antisense uPAR vectors  

Microsoft Academic Search

Our previous studies showed that glioblastomas express increased urokinase-type plasminogen activator receptors (uPARs) in comparison to low-grade gliomas (Yamamoto et al., Cancer Res., 54, 5016-5020, 1994). To explore whether downregulation of uPAR inhibits tumor formation and invasiveness, a human glioblastoma cell line was transfected with a cDNA construct corresponding to 300 bp of the human uPAR's 5¢ end in an

Yoshinori Go; Shravan K. Chintala; Sanjeeva Mohanam; Ziya Gokaslan; Boyapati Venkaiah; Rolf Bjerkvig; Kazunari Oka; Garth L. Nicolson; Raymond Sawaya; Jasti S. Rao

1997-01-01

388

SUR L'OBSERVATION ET L'INTERPRTATION CINMATIQUE DES PHNOMNES DCOUVERTS PAR M. LE Dr ZEEMAN ;  

E-print Network

673 SUR L'OBSERVATION ET L'INTERPR�TATION CIN�MATIQUE DES PH�NOM�NES D�COUVERTS PAR M. LE Dr ZEEMAN ; Par M. A. CORNU. Les phénomènes découverts par M. le Dr Zeeman, relatifs à l'ac- tion d'un champ, p. 53 ; for september 1897, p. 255). - de Plays., 3e série, 143, 655. (2) Un rhomboïde de spath

Paris-Sud XI, Université de

389

Par6–aPKC uncouples ErbB2 induced disruption of polarized epithelial organization from proliferation control  

Microsoft Academic Search

The polarized glandular organization of epithelial cells is frequently lost during development of carcinoma. However, the specific oncogene targets responsible for polarity disruption have not been identified. Here, we demonstrate that activation of ErbB2 disrupts apical–basal polarity by associating with Par6–aPKC, components of the Par polarity complex. Inhibition of interaction between Par6 and aPKC blocked the ability of ErbB2 to

Victoria Aranda; Teresa Haire; Marissa E. Nolan; Joseph P. Calarco; Avi Z. Rosenberg; James P. Fawcett; Tony Pawson; Senthil K. Muthuswamy

2006-01-01

390

ParABS Systems of the Four Replicons of Burkholderia cenocepacia: New Chromosome Centromeres Confer Partition Specificity  

Microsoft Academic Search

Most bacterial chromosomes carry an analogue of the parABS systems that govern plasmid partition, but their role in chromosome partition is ambiguous. parABS systems might be particularly important for orderly segregation of multipartite genomes, where their role may thus be easier to evaluate. We have characterized parABS systems in Burkholderia cenocepacia, whose genome comprises three chromosomes and one low-copy- number

Nelly Dubarry; Franck Pasta

2006-01-01

391

Interaction specificity, toxicity, and regulation of a paralogous set of ParE/RelE-family toxin-antitoxin systems  

PubMed Central

Summary Toxin-antitoxin (TA) gene cassettes are widely distributed across bacteria, archaea, and bacteriophage. The chromosome of the ?-proteobacterium, Caulobacter crescentus, encodes eight ParE/RelE-superfamily toxins that are organized into operons with their cognate antitoxins. A systematic genetic analysis of these parDE and relBE TA operons demonstrates that seven encode functional toxins. The one exception highlights an example of a non-functional toxin pseudogene. Chromosomally-encoded ParD and RelB proteins function as antitoxins, inhibiting their adjacently-encoded ParE and RelE toxins. However, these antitoxins do not functionally complement each other, even when overexpressed. Transcription of these paralogous TA systems is differentially regulated under distinct environmental conditions. These data support a model in which multiple TA paralogs encoded by a single bacterial chromosome form independent functional units with insulated protein-protein interactions. Further characterization of the parDE1 system at the single-cell level reveals that ParE1 toxin functions to inhibit cell division but not cell growth; residues at the C-terminus of ParE1 are critical for its stability and toxicity. While continuous ParE1 overexpression results in a substantial loss in cell viability at the population level, a fraction of cells escape toxicity, providing evidence that ParE1 toxicity is not uniform within clonal cell populations. PMID:20487277

Fiebig, Aretha; Rojas, Cyd Marie Castro; Siegal-Gaskins, Dan; Crosson, Sean

2010-01-01

392

Lipid nanoparticles as delivery vehicles for the Parietaria judaica major allergen Par j 2.  

PubMed

Parietaria pollen is one of the major causes of allergic reaction in southern Europe, affecting about 30% of all allergic patients in this area. Specific immunotherapy is the only treatment able to modify the natural outcome of the disease by restoring a normal immunity against allergens. The preparation of allergen-solid lipid nanoparticles as delivery vehicles for therapeutic proteins, P. judaica major allergen Par j 2, was investigated. The Par j 2 allergen was expressed in a large amount in Escherichia coli and purified to homogeneity. Its immunological properties were studied by western blotting and enzyme-linked immunosorbent assay inhibition. Solid lipid nanoparticles were obtained by water-in-oil-in-water multiple emulsion method and characterized in terms of mean size and surface charge. These systems (approximately 250 nm diameter and negative surface charge) incorporated recombinant Par j 2 with 40% or greater efficiency. Moreover, the endotoxin level and anaphylactic activity of the empty solid lipid nanoparticles and recombinant Par j 2-loaded solid lipid nanoparticles were evaluated by looking at the overexpression of CD203c marker on human basophils. These results demonstrate that recombinant Par j 2-nanoparticles could be proposed as safe compositions for the development of new therapeutic dosage forms to cure allergic reactions. PMID:22162654

Bondì, Maria Luisa; Montana, Giovanna; Craparo, Emanuela Fabiola; Di Gesù, Roberto; Giammona, Gaetano; Bonura, Angela; Colombo, Paolo

2011-01-01

393

par genes and the pathology of chromosome loss in Vibrio cholerae  

PubMed Central

The causes and consequences of chromosome loss in bacteria with multiple chromosomes are unknown. Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has two circular chromosomes. Like many other bacterial chromosomes, both V. cholerae chromosomes contain homologues of plasmid partitioning (par) genes. In plasmids, par genes act to segregate plasmid molecules to daughter cells and thereby ensure plasmid maintenance; however, the contribution of par genes to chromosome segregation is not clear. Here, we show that the chromosome II parAB2 genes are essential for the segregation of chromosome II but not chromosome I. In a parAB2 deletion mutant, chromosome II is mislocalized and frequently fails to segregate, yielding cells with only chromosome I. These cells divide once; their progeny are not viable. Instead, chromosome II-deficient cells undergo dramatic cell enlargement, nucleoid condensation and degradation, and loss of membrane integrity. The highly consistent nature of these cytologic changes suggests that prokaryotes, like eukaryotes, may possess characteristic death pathways. PMID:17197419

Yamaichi, Yoshiharu; Fogel, Michael A.; Waldor, Matthew K.

2007-01-01

394

Lambeaux autofermants pour le traitement des brulures electriques du scalp par haut voltage  

PubMed Central

Summary Les brûlures électriques par haut voltage sont responsables de gros dégâts tissulaires en immédiat et dans les jours suivant l’accident du fait de la chaleur importante dégagée par effet joule et de la thrombose microvasculaire évolutive. Les pertes de substances du scalp secondaires à ces brûlures nécessitent une couverture par lambeaux vu la destruction du périoste et du calvarium en regard. De juin 1997 à juin 2008, 15 patients ont été traités pour des pertes de substance du scalp secondaires à des brûlures électriques par haut voltage de diamètre allant de 8 à 11 cm et siégeant dans la région tonsurale. Ces patients ont été opérés dans la première semaine suivant l’accident. Les pertes de substance du scalp de taille moyenne secondaires à ces brûlures peuvent être couvertes per primam de façon fiable par des lambeaux locaux axialisés et multiples. Nous relatons l’expérience du Service de Chirurgie Plastique du Centre Hospitalier Universitaire Ibn-Sina, Rabat, Maroc, dans la gestion et la prise en charge de ces brûlures. PMID:22262963

Hafidi, J.; El Mazouz, S.; El Mejatti, H.; Fejjal, N.; Gharib, N.E.; Abbassi, A.; Belmahi, A.M.

2011-01-01

395

Nanomechanical recognition of prognostic biomarker suPAR with DVD-ROM optical technology  

NASA Astrophysics Data System (ADS)

In this work the use of a high-throughput nanomechanical detection system based on a DVD-ROM optical drive and cantilever sensors is presented for the detection of urokinase plasminogen activator receptor inflammatory biomarker (uPAR). Several large scale studies have linked elevated levels of soluble uPAR (suPAR) to infectious diseases, such as HIV, and certain types of cancer. Using hundreds of cantilevers and a DVD-based platform, cantilever deflection response from antibody-antigen recognition is investigated as a function of suPAR concentration. The goal is to provide a cheap and portable detection platform which can carry valuable prognostic information. In order to optimize the cantilever response the antibody immobilization and unspecific binding are initially characterized using quartz crystal microbalance technology. Also, the choice of antibody is explored in order to generate the largest surface stress on the cantilevers, thus increasing the signal. Using optimized experimental conditions the lowest detectable suPAR concentration is currently around 5 nM. The results reveal promising research strategies for the implementation of specific biochemical assays in a portable and high-throughput microsensor-based detection platform.

Bache, Michael; Bosco, Filippo G.; Brøgger, Anna L.; Frøhling, Kasper B.; Sonne Alstrøm, Tommy; Hwu, En-Te; Chen, Ching-Hsiu; Eugen-Olsen, Jesper; Hwang, Ing-Shouh; Boisen, Anja

2013-11-01

396

Obtention par PVD de condensateurs à base d'oxyde de germanium amorphe  

NASA Astrophysics Data System (ADS)

This paper describes the elaboration of thin amorphous films of germanium dioxide and mixed germanium and lead oxides by RF cathodic sputtering in order to develop low loss capacitors with the highest possible capacity. The composition and the structure of the films are respectively determined by RBS and EXAFS. The best dielectric characteristics in low frequencies are obtained for the GePb{1.40}O{3.40} material. Cet article décrit l'élaboration par pulvérisation cathodique RF de films minces amorphes de dioxyde de germanium et d'oxydes mixtes de germanium et de plomb dans le but de réaliser des condensateurs à faibles pertes et de plus grande capacité possible. La composition et la structure des films sont déterminées respectivement par RBS et par EXAFS. Les meilleures caractéristiques diélectriques en basses fréquences sont obtenues pour le matériau GePb{1,40}O{3,40}.

Caperaa, C.; Segda, B.; Jacquet, M.; Baud, G.; Besse, J.-P.

1993-04-01

397

Characterization of the stable maintenance properties of the par region of broad-host-range plasmid RK2.  

PubMed Central

A 3.2-kb fragment encoding five genes, parCBA/DE, in two divergently transcribed operons promotes stable maintenance of the replicon of the broad-host-range plasmid RK2 in a vector-independent manner in Escherichia coli. The parDE operon has been shown to contribute to stabilization through the postsegregational killing of plasmid-free daughter cells, while the parCBA operon encodes a resolvase, ParA, that mediates the resolution of plasmid multimers through site-specific recombination. To date, evidence indicates that multimer resolution alone does not play a significant role in RK2 stable maintenance by the parCBA operon in E. coli. It has been proposed, instead, that the parCBA region encodes an additional stability mechanism, a partition system, that ensures that each daughter cell receives a plasmid copy at cell division. However, studies carried out to date have not directly determined the plasmid stabilization activity of the parCBA operon alone. An assessment was made of the relative contributions of postsegregational killing (parDE) and the putative partitioning system (parCBA) to the stabilization of mini-RK2 replicons in E. coli. Mini-RK2 replicons carrying either the entire 3.2-kb (parCBA/DE) fragment or the 2.3-kb parCBA region alone were found to be stably maintained in two E. coli strains tested. The stabilization found is not due to resolution of multimers. The stabilizing effectiveness of parCBA was substantially reduced when the plasmid copy number was lowered, as in the case of E. coli cells carrying a temperature-sensitive mini-RK2 replicon grown at a nonpermissive temperature. The presence of the entire 3.2-kb region effectively stabilized the replicon, however, under both low- and high-copy-number-conditions. In those instances of decreased plasmid copy number, the postsegregational killing activity, encoded by parDE, either as part of the 3.2-kb fragment or alone played the major role in the stabilization of mini-RK2 replicons within the growing bacterial population. Our findings indicate that the parCBA operon functions to stabilize by a mechanism other than cell killing and resolution of plasmid multimers, while the parDE operon functions solely to stabilize plasmids by cell killing. The relative contribution of each system to stabilization depends on plasmid copy number and the particular E. coli host. PMID:8606188

Sobecky, P A; Easter, C L; Bear, P D; Helinski, D R

1996-01-01

398

Molecular Dynamics Simulations and Functional Characterization of the Interactions of the PAR2 Ectodomain with Factor VIIa  

PubMed Central

Signaling of the tissue factor-FVIIa complex regulates angiogenesis, tumor growth and inflammation. TF-FVIIa triggers cell signaling events by cleavage of protease activated receptor (PAR2) at the Arg36-Ser37 scissile bond. The recognition of PAR2 by the FVIIa protease domain is poorly understood. We perform molecular modeling and dynamics simulations to derive the PAR2-FVIIa interactions. Docking of the PAR2 Arg36-Ser37 scissile bond to the S1 site and subsequent molecular dynamics leads to interactions of the PAR2 ectodomain with P and P’ sites of the FVIIa catalytic cleft as well as to electrostatic interactions between a stably folded region of PAR2 and a cluster of basic residues remote from the catalytic cleft of FVIIa. To address the functional significance of this interaction for PAR2 cleavage, we employed two antibodies with epitopes previously mapped to this cluster of basic residues. Although these antibodies do not block the catalytic cleft, both antibodies completely abrogated PAR2 activation by TF-FVIIa. Our simulations indicate a conformation of the PAR2 ectodomain that limits the cleavage site to no more than 33 A from its membrane proximal residue. Since the active site of FVIIa in the TF-FVIIa complex is ~ 75A above the membrane, cleavage of the folded conformation of PAR2 would require tilting of the TF-FVIIa complex toward the membrane, indicating that additional cellular factors may be required to properly align the scissile bond of PAR2 with TF-FVIIa. PMID:19536895

Zhang, Qing; Petersen, Helle H.; Ostergaard, Henrik; Ruf, Wolfram; Olson, Arthur J.

2010-01-01

399

PAR6B is required for tight junction formation and activated PKC? localization in breast cancer  

PubMed Central

Dysregulation of mechanisms that govern the control of epithelial cell polarity, morphology and plasticity are emerging as key processes in tumor progression. In this study we report amplification and overexpression of PAR6B, an essential component in epithelial cell tight junction (TJ) formation and maintenance of apico-basal polarity, in breast cancer cell lines. Analysis of chromosome 20q13.13 in 11 breast cancer cell lines by fluorescence in situ hybridization (FISH) identified a novel small amplicon centered at PARD6B in 5 cell lines, with copy number ranging from 7 to 27. The presence of the PARD6B amplicon correlated with PARD6B transcript and PAR6B protein abundance. Expression of related isoforms PARD6A and PARD6G were detectable at significantly lower levels. PARD6B overexpression correlated with TJ network formation in cultured cell monolayers. SiRNA-mediated inhibition of PAR6B in MCF7 resulted in loss of TJ assembly and membrane localization of atypical PKC? (aPKC), but did not affect adherens junction formation. SiRNA-mediated inhibition of CDC42 in MCF7 also resulted in loss of TJ networks, confirming the requirement of a complete PAR6-aPKC-CDC42-PAR3 complex to activate and stabilize TJs. Immunohistochemical analysis of PAR6B expression on breast tumor microarrays indicated exquisite epithelial cell-specificity. Few quantitative differences in staining were observed between normal epithelium and adjacent tumor margins. However staining appeared reduced and cytoplasmic in more poorly differentiated tumors. We propose that quantitative imbalances in the components of pathways governing normal epithelial cell polarity arising from gain or loss of function may radically alter epithelial cell architecture and contribute to tumor progression. PMID:22957302

Cunliffe, Heather E; Jiang, Yuan; Fornace, Kimberly M; Yang, Fan; Meltzer, Paul S

2012-01-01

400

Factor Xa stimulates fibroblast procollagen production, proliferation, and calcium signaling via PAR{sub 1} activation  

SciTech Connect

Fibroblast proliferation and procollagen production are central features of tissue repair and fibrosis. In addition to its role in blood clotting, the coagulation cascade proteinase thrombin can contribute to tissue repair by stimulating fibroblasts via proteolytic activation of proteinase-activated receptor-1 (PAR{sub 1}). During hemostasis, the coagulation cascade proteinase factor X is converted into factor Xa. We have previously shown that factor Xa upregulates fibroblast proliferation via production of autocrine PDGF. In this study, we further examined the effects of factor Xa on fibroblast function and aimed to identify its signaling receptor. We showed that factor Xa stimulates procollagen promoter activity and protein production by human and mouse fibroblasts. This effect was independent of PDGF and thrombin production, but dependent on factor Xa proteolytic activity. We also showed that PAR{sub 1}-deficient mouse fibroblasts did not upregulate procollagen production, mobilize cytosolic calcium, or proliferate in response to factor Xa. Desensitization techniques and PAR{sub 1}-specific agonists and inhibitors were used to demonstrate that PAR{sub 1} mediates factor Xa signaling in human fibroblasts. This is the first report that factor Xa stimulates extracellular matrix production. In contrast with endothelial cells and vascular smooth muscle cells, fibroblasts appear to be the only cell type in which the effects of factor Xa are mediated mainly via PAR{sub 1} and not PAR{sub 2}. These findings are critical for our understanding of tissue repair and fibrotic mechanisms, and for the design of novel approaches to inhibit the profibrotic effects of the coagulation cascade without compromising blood hemostasis.

Blanc-Brude, Olivier P. [Royal Free and University College London Medical School, Centre for Cardiopulmonary Biochemistry and Respiratory Medicine, 5 University Street, London WC1E 6JJ (United Kingdom)]. E-mail: olivier.blanc-brude@larib.inserm.fr; Archer, Fabienne [University College London Department of Physiology, Bolsover Laboratory, Gower Street, London WC1E 6BT (United Kingdom); Leoni, Patricia [Royal Free and University College London Medical School, Centre for Cardiopulmonary Biochemistry and Respiratory Medicine, 5 University Street, London WC1E 6JJ (United Kingdom); Derian, Claudia [Johnson and Johnson Pharmaceutical Research and Development, LLC, Welsch and McKean roads, Spring House, PA 19477-0776 (United States); Bolsover, Steven [University College London Department of Physiology, Bolsover Laboratory, Gower Street, London WC1E 6BT (United Kingdom); Laurent, Geoffrey J. [Royal Free and University College London Medical School, Centre for Cardiopulmonary Biochemistry and Respiratory Medicine, 5 University Street, London WC1E 6JJ (United Kingdom); Chambers, Rachel C. [Royal Free and University College London Medical School, Centre for Cardiopulmonary Biochemistry and Respiratory Medicine, 5 University Street, London WC1E 6JJ (United Kingdom)

2005-03-10

401

Rullier A et al. PAR-1 knock-out protects against liver fibrosis1 Protease-activated receptor 1 (PAR-1) knock-out reduces experimentally-induced liver  

E-print Network

Rullier A et al. PAR-1 knock-out protects against liver fibrosis1 Protease-activated receptor 1 (PAR-1) knock-out reduces experimentally-induced liver fibrosis. Anne Rullier1, 2 , Jennifer Gillibert Victor Segalen Bordeaux 2, Bordeaux, F-33076 France. Key words : liver fibrosis, hemostasis, thrombin

Paris-Sud XI, Université de

402

Gliome du nerf optique r?v?l? par un strabisme divergent  

PubMed Central

Les gliomes des nerfs optiques sont des tumeurs rares qui s'observent essentiellement chez l'enfant. L'exophtalmie et le strabisme sont les principaux signes révélateurs de la maladie. La neuroimagerie et notamment l'imagerie par résonnance magnétique est d'un grand apport dans le diagnostic et le suivi de ces tumeurs. La prise en charge thérapeutique de ces gliomes fait appel à différents moyens: l'exérèse chirurgicale, la chimiothérapie, la radiothérapie ou l'abstention sous surveillance. Les indications doivent être discutées au cas par cas.

Handor, Hanan; Laghmari, Mina; Hafidi, Zouheir; Daoudi, Rajae

2014-01-01

403

K-Area and Par Pond Sewage Sludge Application Sites groundwater monitoring reports, second quarter 1992  

SciTech Connect

During second quarter 1992, the three wells at the K-Area Sewage Sludge Application Site (KSS wells) and the three wells at the Par Pond Sewage Sludge Application Site (PSS wells) were sampled for analyses required each quarter or annually by South Carolina Department of Health and Environmental Control Construction Permit 13, 173. This report includes the results of those analyses. None of the analyzed constituents exceeded the Primary Drinking Water Standard or the Savannah River Site Flag 2 criteria at either the K-Area Sewage Sludge Application Site or the Par Pond Sewage Sludge Application Site.

Not Available

1992-10-01

404

Nécrolyse épidermique toxique induite par le phénobarbital chez un enfant Rwandais: à propos d'uncas  

PubMed Central

Le syndrome de Lyell ou la nécrolyse épidermique toxique (TEN) est une des rares complications majeures du traitement par phénobarbital. Sa prise en charge n'est pas encore codifiée. Il requiert une intervention urgente, lourde et adaptée à chaque patient afin d'en réduire la mortalité. Nous décrivons un cas du syndrome de Lyell survenu une dizaine de jours après initiation du traitement antiépileptique par phénobarbital chez un enfant rwandais de deux ans. La complexité des lésions cutanéomuqueuses et leurs répercussions sur le plan général soulignent l'importance d'une prescription responsable et justifiée des médicaments antiépileptiques. PMID:25396028

Kaputu-Kalala-Malu, Célestin; Ntumba-Tshitenge, Olga; Misson, Jean-Paul

2014-01-01

405

PROPRITS MAGNTIQUES DU SESQUIOXYDE DE FER Fe2O303B1 Par CHARLES GUILLAUD.  

E-print Network

propriétés de cet oxyde. Observations générales. - Il est capital, pour pouvoir interpréter correctement les, qui dépend de la nature et des conditions de préparation de l'oxyde. C'est ainsi, par exemple, que si d'alun de fer. Nous avons nous-même préparé des oxydes en utilisant un fer très pur (99,99 pour i oo

Boyer, Edmond

406

Accs au texte intgral des articles Accs au texte intgral par le rsolveur de liens / 1  

E-print Network

Accès au texte intégral des articles Accès au texte intégral par le résolveur de liens / 1 ­ Accès aux ressources Pour avoir accès aux ressources et au texte intégral des articles, vous devez articles 2 Accès au texte intégral par le résolveur de liens / 2 La BU est abonnée à la revue Accès au

Maume-Deschamps, Véronique

407

PAR LE Bacillue prodigiosu8 2. LEMELAND, 1921. -Dosage des substances insaponifiables autres que la  

E-print Network

24 #12;370 C. GORINI. -,--- LA PRODUCTION DE PR�SURE' même en l'absenc~ de caséine et de lactose Züchtungsbiologie. - Févr. 1930. LA PRODUCTION DE PR�SURE PAR LE BAO/LLUS PROD/G/OSUS par le Prof. Dr méd pour la première fois que le B. prodigio8u8 produit une présure ou chymase, c'est-à-dire une enzyme

Paris-Sud XI, Université de

408

Le processus de commissionnement vu par le maitre d'ouvrage  

E-print Network

France (tours de refroidissement, proc?d? humide au dessus de 2000 m? environ). ? Chauffage et climatisation par thermo-frigo-pompes sur la nappe phr?atique : zones de nappes phr?atiques puissantes. ATTENTES CONCERNANT LES INTERVENANTS #0;?#0;? Ma?trise d... France (tours de refroidissement, proc?d? humide au dessus de 2000 m? environ). ? Chauffage et climatisation par thermo-frigo-pompes sur la nappe phr?atique : zones de nappes phr?atiques puissantes. ATTENTES CONCERNANT LES INTERVENANTS #0;?#0;? Ma?trise d...

Moro, M.

2004-01-01

409

uPAR and Proteases in Mobilization of Hematopoietic Stem Cells  

Microsoft Academic Search

The specific cell-surface receptor for the urokinase-type plasminogen activator (uPA) was identified in 1985; since then,\\u000a a large body of evidence showed that urokinase-type plasminogen activator receptor (uPAR) was not only the receptor for a\\u000a proteolytic enzyme but also a multifunctional signaling molecule capable of various interactions and activities. In fact,\\u000a uPAR is implicated in several biological events, such as

Pia Ragno; Francesco Blasi

410

duit par seconde et par gramme est donc 1,25.10-9 centimtre cube. Le volume maxinlurn est gal la  

E-print Network

.] [Traduit de l'anglais par L. Dunoyer.] M�MOIRES TRADUITS Chaleur d�velopp�e dans une masse d'oxyde de�rience destin�e � mettre en �vidence et � mesurer la vitesse avec la- quelle une masse d'oxyde de thorium d'exp�rinientatioii consiste bri�vement en ceci : l'oxyde de thorium - (le produit employ� n'�tait pas pur, mais consistait en

Boyer, Edmond

411

pour laquelle OP = p, OP' -~n'. Si OF ~ ~ ~i et OF ~ = ~'1, la pa_ rallle OP mene par F, et la parallle OP mene par F~ se  

E-print Network

s'élève à il et soient x et y les variations des niveaux du mercure. En écrivant que la pression ~ représente celle de la niasse to tale d u mercure et, par suite, De ces deux. équations, on tire Article;78 Donc, si l'on a la position du niveau du mercure dans la cuvette sera invariablc pour la pression

Boyer, Edmond

412

Racial Difference in Human Platelet PAR4 Reactivity Reflects Expression of PCTP and miR-376c  

PubMed Central

Racial differences in the pathophysiology of atherothrombosis are poorly understood. We explored the function and transcriptome of platelets in healthy black (n = 70) and white (n = 84) subjects. PAR4 thrombin receptor induced platelet aggregation and calcium mobilization were significantly greater in black subjects. Numerous differentially expressed (DE) RNAs were associated with both race and PAR4 reactivity, including phosphatidylcholine transfer protein (PCTP), and platelets from blacks expressed higher levels of PC-TP protein. PC-TP inhibition or depletion blocked activation of platelets or megakaryocytic cell lines through PAR4 but not PAR1. MiR-376c levels were DE by race and PAR4 reactivity, and were inversely correlated with PCTP mRNA levels, PC-TP protein levels and PAR4 reactivity. MiR-376c regulated expression of PC-TP in human megakaryocytes. A disproportionately high number of miRNAs DE by race and PAR4 reactivity, including miR-376c, are encoded in the DLK1-DIO3 locus, and were lower in platelets from blacks. These results support PC-TP as a regulator of the racial difference in PAR4-mediated platelet activation, indicate a genomic contribution to platelet function that differs by race, and emphasize a need to consider race effects when developing anti-thrombotic drugs. PMID:24216752

Edelstein, Leonard C.; Simon, Lukas M.; Montoya, Raúl Teruel; Holinstat, Michael; Chen, Edward S.; Bergeron, Angela; Kong, Xianguo; Nagalla, Srikanth; Mohandas, Narla; Cohen, David E.; Dong, Jing-fei; Shaw, Chad; Bray, Paul F.

2013-01-01

413

Soyez forms et challengs par des entrepreneurs expriments Des ateliers pratiques pour lancer et faire crotre votre entreprise  

E-print Network

Soyez formés et challengés par des entrepreneurs expérimentés Des ateliers pratiques pour lancer et conçues par des entrepreneurs pour des entrepreneurs. Elles sont l'occasion pour les participants, que ce jalons, non seulement d'apprendre les ficelles pour être un entrepreneur à succès, mais d

Rochaix, Jean-David

414

Vers une formule de Stirling de la factorielle de Bhargava pour des entiers reconnaissables par un automate  

E-print Network

Vers une formule de Stirling de la factorielle de Bhargava pour des entiers reconnaissables par un¸con intrins`eque en th´eorie des nombres. Ainsi l'estimation de cette fonction par la formule de Stirling se r savoir quel est l'analogue de la formule de Stirling pour un sous ensemble E ? Quels sont les propri

Dumont, Serge

415

Urokinase-type plasminogen activator receptor (uPAR) as a promising new imaging target: potential clinical applications  

PubMed Central

Urokinase-type plasminogen activator receptor (uPAR) has been shown to be of special importance during cancer invasion and metastasis. However, currently, tissue samples are needed for measurement of uPAR expression limiting the potential as a clinical routine. Therefore, non-invasive methods are needed. In line with this, uPAR has recently been identified as a very promising imaging target candidate. uPAR consists of three domains attached to the cell membrane via a glycosylphosphatidylinositol (GPI) anchor and binds it natural ligand uPA with high affinity to localize plasminogen activation at the cell surface. Due to the importance of uPAR in cancer invasion and metastasis, a number of high-affinity ligands have been identified during the last decades. These ligands have recently been used as starting point for the development of a number of ligands for imaging of uPAR using various imaging modalities such as optical imaging, magnetic resonance imaging, single photon emission computer tomography (SPECT) and positron emission topography (PET). In this review, we will discuss recent advances in the development of uPAR-targeted imaging ligands according to imaging modality. In addition, we will discuss the potential future clinical application for uPAR imaging as a new imaging biomarker. PMID:23701192

Persson, Morten; Kjaer, Andreas

2013-01-01

416

ANRS12154Pecan_NVP_v1_dernier enregistrement par Anne-Marie Population pharmacokinetic-pharmacogenetic study of1  

E-print Network

1 ANRS12154Pecan_NVP_v1_dernier enregistrement par Anne-Marie Population pharmacokinetic-pharmacogenetic Pharmacogenetic Hormonology department and EA2706 Univ Paris Sud, France,12 5 Epidemiology and Public Health Unit, pharmacogenetics,4 5 #12;4 ANRS12154Pecan_NVP_v1_dernier enregistrement par Anne-Marie Introduction1 In resource

Paris-Sud XI, Université de

417

Apprendre l'informatique par la programmation des robots Claver Nijimbere, Ltitia Boulc'h, Mariam Haspekian, Georges Louis Baron  

E-print Network

1 Apprendre l'informatique par la programmation des robots Claver Nijimbere, Lætitia Boulc'apprentissage de l'informatique ­ la programmation des robots - chez les étudiants de licence en début d-clés : Robotique MINDSTORMS NXT, didactique, pédagogie par projets, apprentissage, programmation informatique

Boyer, Edmond

418

Immunocytochemical studies on the pituitary pars distalis of the Japanese long-fingered bat, Miniopterus schreibersii fuliginosus  

Microsoft Academic Search

Immunocytochemical studies were performed to describe the characteristics of cell types and their distribution in the pars distalis of Japanese long-fingered bat, Miniopterus schreibersii fuliginosus, collected at various stages of the reproductive cycle. Six distinct cell types have been identified in the pars distalis by the unlabeled immunoperoxidase technique and by the ABC method. Growth hormone (GH) and prolactin (PRL)

Shin-ichi Mikami; Shin Chiba; Hitoshi Hojo; Kazuyuki Taniguchi; Kaoru Kubokawa; Susumu Ishii

1988-01-01

419

The distribution and nature of gonadotropic cells in the rostral pars distalis of the Atlantic salmon, Salmo salar  

E-print Network

salmon, Salmo salar B. EKENGREN J. PEUTE G. FRIDBERG University of Stockholm, Department of Zoology, Box the gonadotropic (GTH) cells in the rostral pars distalis (RPD) of the pituitary in the Atlantic salmon in phases are generally distributed in the proximal pars distalis. In the sockeye salmon the GTH cells also occur

Paris-Sud XI, Université de

420

Structural mechanism of ATP-induced polymerization of the partition factor ParF: implications for DNA segregation.  

PubMed

Segregation of the bacterial multidrug resistance plasmid TP228 requires the centromere-binding protein ParG, the parH centromere, and the Walker box ATPase ParF. The cycling of ParF between ADP- and ATP-bound states drives TP228 partition; ATP binding stimulates ParF polymerization, which is essential for segregation, whereas ADP binding antagonizes polymerization and inhibits DNA partition. The molecular mechanism involved in this adenine nucleotide switch is unclear. Moreover, it is unknown how any Walker box protein polymerizes in an ATP-dependent manner. Here, we describe multiple ParF structures in ADP- and phosphomethylphosphonic acid adenylate ester (AMPPCP)-bound states. ParF-ADP is monomeric but dimerizes when complexed with AMPPCP. Strikingly, in ParF-AMPPCP structures, the dimers interact to create dimer-of-dimer "units" that generate a specific linear filament. Mutation of interface residues prevents both polymerization and DNA segregation in vivo. Thus, these data provide insight into a unique mechanism by which a Walker box protein forms polymers that involves the generation of ATP-induced dimer-of-dimer building blocks. PMID:22674577

Schumacher, Maria A; Ye, Qiaozhen; Barge, Madhuri T; Zampini, Massimiliano; Barillà, Daniela; Hayes, Finbarr

2012-07-27

421

Traitement des coques de tournesol par vapocraquage : influence sur la composition et la dgradation in sacco des polyosides  

E-print Network

. (*) CERMAV, C.N.R.S., B.P. 68, 38402 St- Martin- dhères Cedex. Summary. Steam-explosion of sunflower hulls traités par vapocraquage (vapeur à 35 bars pendant 1 min, puis explosion par détente), récupérés

Boyer, Edmond

422

A Type Ib ParB Protein Involved in Plasmid Partitioning in a Gram-Positive Bacterium?  

PubMed Central

Our current understanding of segregation of prokaryotic plasmids has been derived mainly from the study of the gram-negative bacterial plasmids. We previously reported a replicon of the cryptic plasmid from a gram-positive bacterium, Leifsonia xyli subsp. cynodontis. The replicon contains a putative plasmid partition cassette including a Walker-type ATPase followed by open reading frame 4 without sequence homologue. Here we reported that the orf4 gene was essential for maintaining the plasmid stability in L. xyli subsp. cynodontis. Furthermore, the purified orf4 protein specifically and cooperatively bound to direct repeat sequences located upstream of the parA gene in vitro, indicating that orf4 is a parB gene and that the direct repeat DNA sequences constitute a partition site, parS. The location of parS and the features of ParA and ParB proteins suggest that this plasmid partition cassette belongs to type Ib, representing the first type Ib cassette identified from a gram-positive bacterial plasmid. PMID:16997970

Yin, Ping; Li, Tai-Yuan; Xie, Mao-Hua; Jiang, Lina; Zhang, Yi

2006-01-01

423

ScalParC : A New Scalable and Efficient Parallel Classification Algorithm for Mining Large Datasets \\Lambda  

E-print Network

or genetic models [9]. The decision­tree based classifiers that handle large datasets are attractive, becauseParC (Scalable Parallel Classifier), a new parallel formulation of a decision tree based classification process. Like other state­of­the­art decision tree classifiers such as SPRINT, ScalParC is suited for handling

Kumar, Vipin

424

A novel repressor, par-4, modulates transcription and growth suppression functions of the Wilms' tumor suppressor WT1.  

PubMed

The tumor suppressor WT1 represses and activates transcription. The loss and/or imbalance of the dual transcriptional activity of WT1 may contribute to Wilms' tumor. In this study, we identified par-4 (for prostate apoptosis response) as a WT1-interacting protein that itself functions as a transcriptional repressor. par-4 contains a putative leucine zipper domain and is specifically upregulated during apoptosis of prostate cells (S. F. Sells, D. P. Wood, Jr., S. S. Joshi-Barve, S. Muthukkumar, R. J. Jacob, S. A. Crist, S. Humphreys, and V. M. Rangnekar, Cell Growth Differ. 5:457-466, 1994). The leucine repeat domain of par-4 was shown to interact with the zinc finger DNA binding domain of WT1. Immunoprecipitation-Western blot (immunoblot) analyses demonstrated in vivo WT1-par-4 interactions. par-4 was ubiquitously expressed, and the protein was found in both the nucleus and the cytoplasm. Functionally, par-4 inhibited transcription activated by WT1, but not by the related protein EGR1. Inhibition of WT1-mediated transcription was dependent on the domain of par-4 that mediates its physical association with WT1. In addition, par-4 augmented WT1-mediated repression, possibly by contributing an additional repression domain. Consistent with these results, par-4 functioned as a transcriptional repressor when brought to a promoter via a heterologous DNA binding domain. Significantly, par-4, but not a mutant unable to interact with WT1, rescued growth suppression caused by WT1. Thus, we identified a novel repressor that modulates transcription as well as growth suppression functions of WT1. PMID:8943350

Johnstone, R W; See, R H; Sells, S F; Wang, J; Muthukkumar, S; Englert, C; Haber, D A; Licht, J D; Sugrue, S P; Roberts, T; Rangnekar, V M; Shi, Y

1996-12-01

425

Expression of antisense uPAR and antisense uPA from a bicistronic adenoviral construct inhibits glioma cell invasion, tumor growth, and angiogenesis  

Microsoft Academic Search

Urokinase-type plasminogen activator (uPA) and its receptor (uPAR) play an important role in the invasiveness of gliomas and other infiltrative tumors. In glioma cell lines and tumors, high grade correlates with increased expression of uPAR and uPA. We report here the downregulation of uPAR and uPA by delivery of antisense sequences of uPAR and uPA in a single adenoviral vector,

Christopher S Gondi; Sajani S Lakka; Niranjan Yanamandra; Khawar Siddique; Dzung H Dinh; William C Olivero; Meena Gujrati; Jasti S Rao

2003-01-01

426

Both Increased Stability and Transcription Contribute to the Induction of the Urokinase Plasminogen Activator Receptor (uPAR) Message by Hypoxia  

Microsoft Academic Search

Both hypoxia and overexpression of the urokinase plasminogen activator receptor (uPAR) are associated with a poor clinical outcome in human cancers. Hypoxia has been shown to induce uPAR expression in breast cancer cells and to increase their invasion through Matrigel, a phenomenon which can be blocked using an anti-uPAR antibody. We examined expression of uPAR mRNA in MCF7 human breast

Amit Maity; Don Solomon

2000-01-01

427

Essai d'amlioration de la rsistance la scheresse du tournesol (Helianthus annuus) par croisement interspci-  

E-print Network

Essai d'amélioration de la résistance à la sécheresse du tournesol (Helianthus annuus) par Helianthus annuus x H. argophyllus a été effectué en 1977 dans le but d'obtenir de nouveaux cultivars de argophyllus. Methodology and first results. An interspecific cross between Helianthus annuus and Helianthus

Paris-Sud XI, Université de