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Understanding follicle growth in vitro: Are we getting closer to obtaining mature oocytes from in vitro‐grown follicles in human? 下载免费PDF全文
Obtaining and fertilizing mature oocytes from immature follicles that were grown outside the body has conceptually attracted scientists for centuries, with initial attempts first documented in the 19th century. Significant progress has been made since then, due in part to a better understanding of folliculogenesis and improved techniques of in vitro follicle growth. Indeed, in vitro growth is now considered a reasonable approach to preserve or restore fertility when immature follicles and their oocytes need to be grown and matured outside the body. Certain patients would benefit from in vitro follicle growth, particularly those who carry a risk of cancer re‐seeding after grafting of frozen‐thawed ovarian tissue or who are at the risk of premature ovarian failure due to several intrinsic ovarian defects and genetic mutations that lead to accelerated follicle atresia and early exhaustion of the ovarian reserve. This review provides an update on the current status of in vitro growth of preantral human follicles, from initial efforts to the most recent achievements. 相似文献
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Cumming JN Le TX Babu S Carroll C Chen X Favreau L Gaspari P Guo T Hobbs DW Huang Y Iserloh U Kennedy ME Kuvelkar R Li G Lowrie J McHugh NA Ozgur L Pan J Parker EM Saionz K Stamford AW Strickland C Tadesse D Voigt J Wang L Wu Y Zhang L Zhang Q 《Bioorganic & medicinal chemistry letters》2008,18(11):3236-3241
Guided by structure-based design, we synthesized two novel series of potent inhibitors of BACE1 and generated extensive SAR around both the prime and non-prime side binding pockets. The key feature of both series is a cyclic amine motif specifically crafted to achieve interactions with both the flap and with the S2' pocket. 相似文献
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Iron (Fe) deficiency is increasingly being observed in cropping systems with frequent glyphosate applications. A likely reason for this is that glyphosate interferes with root uptake of Fe by inhibiting ferric reductase in roots required for Fe acquisition by dicot and nongrass species. This study investigated the role of drift rates of glyphosate (0.32, 0.95 or 1.89 mm glyphosate corresponding to 1, 3 and 6% of the recommended herbicidal dose, respectively) on ferric reductase activity of sunflower (Helianthus annuus) roots grown under Fe deficiency conditions. Application of 1.89 mm glyphosate resulted in almost 50% inhibition of ferric reductase within 6 h and complete inhibition 24 h after the treatment. Even at lower rates of glyphosate (e.g. 0.32 mm and 0.95 mm), ferric reductase was inhibited. Soluble sugar concentration and the NAD(P)H oxidizing capacity of apical roots were not decreased by the glyphosate applications. To our knowledge, this is the first study reporting the effects of glyphosate on ferric reductase activity. The nature of the inhibitory effect of glyphosate on ferric reductase could not be identified. Impaired ferric reductase could be a major reason for the increasingly observed Fe deficiency in cropping systems associated with widespread glyphosate usage. 相似文献
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Callum Cooper Fatih Buyuk Bettina Schelkle Aliye Gulmez Saglam Elif Celik Ozgur Celebi Mitat Sahin Tom Hawkyard Les Baillie 《Antonie van Leeuwenhoek》2017,110(1):167-170
The Bacillus anthracis virulence plasmid pXO2, which encodes for a polypeptide capsule, can be lost during long term laboratory storage. To determine if pXO2 is lost in nature we screened B. anthracis isolates obtained from B. anthracis spores from contaminated animal burial sites in Turkey for their ability to express a capsule upon primary culture. A total of 672 B. anthracis colonies were examined of which ten produced a mixed mucoid (capsule +ve)/non-mucoid (capsule ?ve) phenotype and a further one colony yielded non-mucoid colonies upon repeated culture. Screening by PCR using pXO2 specific primers revealed that seven of these isolates had eliminated the plasmid. Of the four colonies which were positive by PCR, one regained the ability to express a capsule upon repeated culture suggesting that the defect was reversible. This is an important observation as capsule expression is a principal marker of virulence and in the absence of PCR serves as a key diagnostic marker. The results of this preliminary study suggest that pXO2 is lost in nature and that further studies are need to determine the mechanisms by which this occurs. 相似文献
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Haluk Akin Huseyin Onay Emre Turker Ozgur Cogulu Ferda Ozkinay 《Molecular biology reports》2010,37(1):93-98
Familial Mediterranean Fever (FMF) which is frequently present in Mediterranean populations is caused by mutations in the
MEFV gene. According to recent data, MEFV mutations are not the only cause of FMF, but these are major genetic determinants which cause FMF. It has also been suggested
that there may be a number of other genes causing FMF. The MEFV gene is located at 16p13.3 and encodes a protein, pyrin/marenostrin. More than 70 disease associated mutations and totally
186 mutations and polymorphisms have been defined in affected individuals. We have retrospectively evaluated the molecular
test results of 1,201 patients identified as having FMF clinical symptoms referred to the Molecular Genetics Laboratory of
the Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir/Turkey over the last 4 years. Patients were
tested for 12 common mutations in the MEFV gene using a strip assay method (Innogenetics, Belgium). Out of the 1,201 patients tested (2,402 chromosomes) in the Aegean
region in Turkey, 654 (54.45%) did not carry any mutations, among the 547 (45.55%) patients with mutations 246 patients were
either homozygous (101) or compound heterozygous (145), 296 carried only one detected mutation, and five patients had three
mutations. Allelic frequencies for the four most common mutations in the mutation positive groups were 47.60% (M694V), 16.75%
(E148Q), 12.95% (V726A), 11.94% (M680I G/C).The remaining alleles (10.76%) showed rare mutations which were R761H, P369S,
A744S, K695R, F479L, M694I. When the frequencies of mutations detected in our group were compared to the frequencies reported
in the other regions of Turkey, an increase in V726A mutation frequency was observed. No patient showed a I692del mutation
which is sometimes evident in other Mediterranean populations. 相似文献
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OBJECTIVE: To assess ocular surface changes in patients with chronic renal failure (CRF), to compare the results with the duration of illness. STUDY DESIGN: Impression cytology from 48 patients with CRF on regular hemodialysis and 16 age- and sex-matched control subjects were studied. Specimens were taken from the temporal bulbar conjunctiva using cellulose acetate filter paper. RESULTS: Among the patients with CRF who were ill for 0-10 years, 25 patients (78.1%) disclosed grade 0-1, and 7 patients (21.9%) disclosed grade 2-3 cytologic changes, whereas in those with the duration of CRF > 10 years, 9 patients (56.2%) had grade 0-1 and 7 patients (43.8%) had grade 2-3 changes. Specimens from the control group revealed 93.8% grade 0-1 and 6.2% grade 2-3 changes (p < 0.05). CONCLUSION: The ocular surfaces of patients with CRF differ significantly from those of normal individuals, and the severity of conjunctival changes is related to the duration of CRF. 相似文献
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Kurt O Demirel M Ostan I Sevil NR Mandiracioglu A Tanyuksel M Ak M Dagci H 《The new microbiologica》2008,31(3):393-400
Amoebiasis is a common and life-threatening disease. The discrimination of the pathogenic Entamoeba histolytica from the non-pathogenic Entamoeba dispar could be done by advanced methods such as enzyme immunoassay (EIA) and PCR. The aim of this study was to investigate the prevalence of amoebiasis in Izmir province, and differentiate the Entamoeba species by PCR and EIA. Stool samples of 2,047 individuals were examined by direct microscopy, formalin ethyl acetate concentration, trichrome staining and culture, and those found to be positive for E. histolytica/dispar by any of these methods were further analyzed by PCR and EIA for species identification. Fifty-nine of 2,047 (2.9%) stool samples were found to be positive for E. histolytica/dispar with microscopy and/or culture. Among these positive samples, E. histolytica was detected in 14 (23.7%) and 5 (8.5%) samples with PCR and antigen-specific ELISA (EIA), respectively. E. dispar was diagnosed in 31 (52.5%) and 52 (88.1%) of 59 samples with species-specific PCR and EIA, respectively. Risk factors related to infection with Entamoeba spp. and other intestinal parasites included living in shanty houses (p < 0.01), a history of recent immigration to Izmir (p < 0.01), having no social security (p < 0.05) and living with a crowded family (p < 0.01). The results demonstrated the significance of amoebiasis as a public health problem among people with low socio-economic status in Izmir province. 相似文献