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51.
PJ?Baker H?Johnston M?Abel HM?Charlton PJ?O'ShaughnessyEmail author 《Reproductive biology and endocrinology : RB&E》2003,1(1):4
During mammalian testis development distinct generations of fetal and adult Leydig cells arise. Luteinising hormone (LH) is
required for normal adult Leydig cell function and for the establishment of normal adult Leydig cell number but its role in
the process of adult Leydig cell differentiation has remained uncertain. In this study we have examined adult Leydig cell
differentiation in gonadotrophin-releasing hormone (GnRH)-null mice which are deficient in circulating gonadotrophins. Adult
Leydig cell differentiation was assessed by measuring expression of mRNA species encoding four specific markers of adult Leydig
cell differentiation in the mouse. Each of these markers (3β-hydroxysteroid dehydrogenase type VI (3βHSD VI), 17β-hydroxysteroid
dehydrogenase type III (17βHSD III), prostaglandin D (PGD)-synthetase and oestrogen sulphotransferase (EST)) is expressed
only in the adult Leydig cell lineage in the normal adult animal. Real-time PCR studies showed that all four markers are expressed
in adult GnRH-null mice. Localisation of 3βHSD VI and PGD-synthetase expression by in situ hybridisation confirmed that these genes are expressed in the interstitial tissue of the GnRH-null mouse. Treatment of animals
with human chorionic gonadotrophin increased expression of 3βHSD VI and 17βHSD III within 12 hours further indicating that
differentiated, but unstimulated cells already exist in the GnRH-null mouse. Thus, while previous studies have shown that
LH is required for adult Leydig cell proliferation and activity, results from the present study show that adult Leydig cell
differentiation will take place in animals deficient in LH. 相似文献
52.
Hanna W van Steenbergen Luis Rodríguez-Rodríguez Ewa Berglin Alexandra Zhernakova Rachel Knevel Jose Ivorra-Cortés Tom WJ Huizinga Benjamin Fernández-Gutiérrez Peter K Gregersen Solbritt Rantap??-Dahlqvist Annette HM van der Helm-van Mil 《Arthritis research & therapy》2015,17(1)
IntroductionThe severity of joint damage progression in rheumatoid arthritis (RA) is heritable. Several genetic variants have been identified, but together explain only part of the total genetic effect. Variants in Interleukin-6 (IL-6), Interleukin-10 (IL-10), C5-TRAF1, and Fc-receptor-like-3 (FCRL3) have been described to associate with radiographic progression, but results of different studies were incongruent. We aimed to clarify associations of these variants with radiographic progression by evaluating six independent cohorts.MethodsIn total 5,895 sets of radiographs of 2,493 RA-patients included in six different independent datasets from the Netherlands, Sweden, Spain and North-America were studied in relation to rs1800795 (IL-6), rs1800896 (IL-10), rs2900180 (C5-TRAF1) and rs7528684 (FCRL3). Associations were tested in the total RA-populations and in anti-citrullinated peptide antibodies (ACPA)-positive and ACPA-negative subgroups per cohort, followed by meta-analyses. Furthermore, the associated region C5-TRAF1 was fine-mapped in the ACPA-negative Dutch RA-patients.ResultsNo associations were found for rs1800795 (IL-6), rs1800896 (IL-10) and rs7528684 (FCRL3) in the total RA-population and after stratification for ACPA. Rs2900180 in C5-TRAF1 was associated with radiographic progression in the ACPA-negative population (P-value meta-analysis = 5.85 × 10−7); the minor allele was associated with more radiographic progression. Fine-mapping revealed a region of 66Kb that was associated; the lowest P-value was for rs7021880 in TRAF1. The P-value for rs7021880 in meta-analysis was 6.35 × 10−8. Previous studies indicate that the region of rs7021880 was associated with RNA expression of TRAF1 and C5.ConclusionVariants in IL-6, IL-10 and FCRL3 were not associated with radiographic progression. Rs2900180 in C5-TRAF1 and linked variants in a 66Kb region were associated with radiographic progression in ACPA-negative RA.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0514-0) contains supplementary material, which is available to authorized users. 相似文献53.
Hans-Georg König Markus Rehm Daniel Gudorf Stan Krajewski Atan Gross Manus W Ward Jochen HM Prehn 《BMC cell biology》2007,8(1):7
Background
Bcl-2 homology domain (BH) 3-only proteins are pro-apoptotic proteins of the Bcl-2 family that couple stress signals to the mitochondrial cell death pathways. The BH3-only protein Bid can be activated in response to death receptor activation via caspase 8-mediated cleavage into a truncated protein (tBid), which subsequently translocates to mitochondria and induces the release of cytochrome-C. Using a single-cell imaging approach of Bid cleavage and translocation during apoptosis, we have recently demonstrated that, in contrast to death receptor-induced apoptosis, caspase-independent excitotoxic apoptosis involves a translocation of full length Bid (FL-Bid) from the cytosol to mitochondria. We induced a delayed excitotoxic cell death in cultured rat hippocampal neurons by a 5-min exposure to the glutamate receptor agonist N-methyl-D-aspartate (NMDA; 300 μM). 相似文献54.
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56.
Executioner caspases such as Caspase-3 and Caspase-7 have long been recognised as the key proteases involved in cell demolition during apoptosis. Caspase activation also modulates signal transduction inside cells, through activation or inactivation of kinases, phosphatases and other signalling molecules. Interestingly, a series of recent studies have demonstrated that caspase activation may also influence signal transduction and gene expression changes in neighbouring cells that themselves did not activate caspases. This review describes the physiological relevance of paracrine Caspase-3 signalling for developmental processes, tissue homeostasis and tissue regeneration, and discusses the role of soluble factors and microparticles in mediating these paracrine activities. While non-cell autonomous control of tissue regeneration by Caspase-3 may represent an important process for maintaining tissue homeostasis, it may limit the efficiency of current cancer therapy by promoting cell proliferation in those cancer cells resistant to radio- or chemotherapy. We discuss recent evidence in support of such a role for Caspase-3, and discuss its therapeutic implication. 相似文献
57.
Reza Shirzadian-Khorramabad Hai-Chun Jing Gerja E Everts Jos HM Schippers Jacques Hille Paul P Dijkwel 《BMC plant biology》2010,10(1):80
Background
Cysteine is a component in organic compounds including glutathione that have been implicated in the adaptation of plants to stresses. O-acetylserine (thiol) lyase (OAS-TL) catalyses the final step of cysteine biosynthesis. OAS-TL enzyme isoforms are localised in the cytoplasm, the plastids and mitochondria but the contribution of individual OAS-TL isoforms to plant sulphur metabolism has not yet been fully clarified. 相似文献58.
Zepeda-Lopez HM Perea-Araujo L Miliar-García A Dominguez-López A Xoconostle-Cázarez B Lara-Padilla E Ramírez Hernandez JA Sevilla-Reyes E Orozco ME Ahued-Ortega A Villaseñor-Ruiz I Garcia-Cavazos RJ Teran LM 《PloS one》2010,5(10):e13256
Background
Influenza viruses pose a threat to human health because of their potential to cause global disease. Between mid March and mid April a pandemic influenza A virus emerged in Mexico. This report details 202 cases of infection of humans with the 2009 influenza A virus (H1N1)v which occurred in Mexico City as well as the spread of the virus throughout the entire country.Methodology and Findings
From May 1st to May 5th nasopharyngeal swabs, derived from 751 patients, were collected at 220 outpatient clinics and 28 hospitals distributed throughout Mexico City. Analysis of samples using real time RT-PCR revealed that 202 patients out of the 751 subjects (26.9%) were confirmed to be infected with the new virus. All confirmed cases of human infection with the strain influenza (H1N1)v suffered respiratory symptoms. The greatest number of confirmed cases during the outbreak of the 2009 influenza A (H1N1)v were seen in neighbourhoods on the northeast side of Mexico City including Iztapalapa, Gustavo A. Madero, Iztacalco, and Tlahuac which are the most populated areas in Mexico City. Using these data, together with data reported by the Mexican Secretariat of Health (MSH) to date, we plot the course of influenza (H1N1)v activity throughout Mexico.Conclusions
Our data, which is backed up by MSH data, show that the greatest numbers of the 2009 influenza A (H1N1) cases were seen in the most populated areas. We speculate on conditions in Mexico which may have sparked this flu pandemic, the first in 41 years. We accept the hypothesis that high population density and a mass gathering which took in Iztapalapa contributed to the rapid spread of the disease which developed in three peaks of activity throughout the Country. 相似文献59.
60.
Niki M. Stolwijk Jacques Duysens Jan Willem K. Louwerens Yvonne HM. van de Ven No?l LW. Keijsers 《PloS one》2013,8(2)
In contrast to western countries, foot complaints are rare in Africa. This is remarkable, as many African adults walk many hours each day, often barefoot or with worn-out shoes. The reason why Africans can withstand such loading without developing foot complaints might be related to the way the foot is loaded. Therefore, static foot geometry and dynamic plantar pressure distribution of 77 adults from Malawi were compared to 77 adults from the Netherlands. None of the subjects had a history of foot complaints. The plantar pressure pattern as well as the Arch Index (AI) and the trajectory of the center of pressure during the stance phase were calculated and compared between both groups. Standardized pictures were taken from the feet to assess the height of the Medial Longitudinal Arch (MLA). We found that Malawian adults: (1) loaded the midfoot for a longer and the forefoot for a shorter period during roll off, (2) had significantly lower plantar pressures under the heel and a part of the forefoot, and (3) had a larger AI and a lower MLA compared to the Dutch. These findings demonstrate that differences in static foot geometry, foot loading, and roll off technique exist between the two groups. The advantage of the foot loading pattern as shown by the Malawian group is that the plantar pressure is distributed more equally over the foot. This might prevent foot complaints. 相似文献