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31.
Navarrete-Palacios E Hudson R Reyes-Guerrero G Guevara-Guzmán R 《Biological psychology》2003,63(3):269-279
We investigated whether olfactory detection threshold is correlated with phase of the menstrual cycle. Three hundred and thirty-two women 13-49 years old were tested once during either the follicular, ovulatory, luteal or menstrual phase, and 15 women 20-43 years old were tested at each of these phases across one complete cycle. In three non-cycling control groups subjects were each tested once; 83 post-menopausal women 47-86 years old, 60 pre-pubertal girls 5-12 years old, and 183 men 17-30 years old. Odor detection thresholds were determined using sniff bottles containing -log9.5 to -log6.0 concentrations of amyl acetate presented in ascending order. Thresholds differed significantly across the cycle and were lowest during the ovulatory and highest during the menstrual phase. Thresholds for all control groups were higher than for the cycling women during the ovulatory phase. The results confirm that olfactory threshold is related to phase of the menstrual cycle and thus possibly to hormonal state. 相似文献
32.
Activins are members of the transforming growth factor-beta (TGFbeta) superfamily, which regulate cell differentiation processes. Here we report the first quantitative analysis of the expression of Activin/Inhibin ligands, type I and II receptors, as well as Smad proteins in fetal (E14-E16) and adult thymic subpopulations. Our data showed that Alk4, ActRIIA, ActRIIB, and Smads 2, 3, and 4, are expressed in fetal thymus (E14 > E15 > E16) and in thymocytes from adult mice (mostly in the double negative [DN] subpopulation). Ligand expression analysis showed that betaA, betaB, and alpha subunits were mainly detected in thymic stromal cells. Interestingly, alpha subunits were expressed at much higher levels compared to betaA and betaB subunits, demonstrating for the first time the potential role of Inhibins as important mediators during early T cell development. Our data indicate that Activin/Inhibin signaling could regulate the process of thymus organogenesis and early thymocyte differentiation, as it has been demonstrated for other members of the TGF-beta superfamily. 相似文献
33.
Maria Cabrerizo Juan E Echevarria Almudena Otero Paloma Lucas Gloria Trallero 《Journal of clinical virology》2008,43(3):323-327
BACKGROUND: Coxsackievirus A24 variant is one of the major etiological agents involved in acute haemorrhagic conjunctivitis. STUDY DESIGN: An outbreak of acute hemorrhagic conjunctivitis occurred in the Southeast of Spain between September and November 2004. Cellular and molecular methods were used to identify and characterize the viral agent associated with the epidemic. RESULTS: Enterovirus was detected in the conjunctival swabs of 35 patients. None of the viruses isolated could be typed by conventional neutralization assays; however, amplification and sequencing of the 3'-end VP1 region of 19 of the samples identified coxsackievirus A24 variant as the serotype causing the outbreak. Phylogenetic analysis of the 5'-half VP1 region of the genome revealed that Spanish sequences, like other strains isolated during outbreaks of hemorrhagic conjunctivitis in American and African countries in 2003 and 2004, were closely related to the isolates detected in Korea (2002), thus proving their worldwide spread. CONCLUSIONS: This is the first report of an epidemic of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant in Spain. Molecular typing in combination with phylogenetic analysis is useful to study the enterovirus epidemiology associated with epidemics. 相似文献
34.
Genotypes and haplotypes in the IL-1 gene cluster: analysis of two genetically and diagnostically distinct groups of Alzheimer patients 总被引:5,自引:0,他引:5
Seripa D Matera MG Dal Forno G Gravina C Masullo C Daniele A Binetti G Bonvicini C Squitti R Palermo MT Davis DG Antuono P Wekstein DR Dobrina A Gennarelli M Fazio VM 《Neurobiology of aging》2005,26(4):455-464
Increased risk of Alzheimer's disease (AD) has been associated with polymorphisms in the IL-1 gene cluster, and in particular with the IL-1alpha-889 T/T genotype. However, this association is still unclear, and needs further investigation. In order to clarify the role of these polymorphisms in the complex pathogenesis of AD we examined genotype and haplotype frequencies of the two C-to-T SNPs at position -889 and -551 in the IL-1alpha and IL-1beta genes, respectively, and of the 86 bp VNTR intron-2 polymorphisms in the IL-1Ra gene. The analysis was performed in two genetically and diagnostically distinct groups of sporadic AD from Italy and the USA. In the Italian group a significant association between the IL-1alpha-889 T/T genotype and AD (OR=3.022, 95% CI: 1.001-9.119) was found, whereas no difference was found in the group from the USA. Results were also compared with previously published studies that analyzed the same IL-1 polymorphisms in AD. In both groups, the analysis of the estimated haplotypes shows that AD patients and controls who carry the IL-1beta-511 C allele, were also more frequently carriers of the IL-1Ra 1 allele (haplotypes -C-1). The total frequency of the two -C-1 haplotypes (C-C-1 plus T-C-1) was about one half of the total frequency of the eight estimated haplotypes. This was confirmed by significant linkage disequilibrium between these two loci in both the Italian and USA groups. In the Italian group a weak association of the T-C-2 haplotype with the disease (OR=1.648, 95% CI: 1.519-1.788) was also found, whereas in the USA group no difference was found. Although ours and other published data on different samples of Caucasian and non-Caucasian AD show a great heterogeneity in the frequencies of the IL-1alpha-889, the IL-1beta-511 and the IL-1Ra VNTR gene polymorphisms, we confirm the role of the IL-1alpha-889 T/T genotype as a risk factor for sporadic AD, and show the presence of an allelic association between IL-1beta C and IL-1Ra 1 alleles in both the Italian and the USA groups, confirmed by the presence of significant levels of linkage disequilibrium between these two loci. 相似文献
35.
PCR assays for identification of Coccidioides posadasii based on the nucleotide sequence of the antigen 2/proline-rich antigen 下载免费PDF全文
Bialek R Kern J Herrmann T Tijerina R Ceceñas L Reischl U González GM 《Journal of clinical microbiology》2004,42(2):778-783
A conventional nested PCR and a real-time LightCycler PCR assay for detection of Coccidioides posadasii DNA were designed and tested in 120 clinical strains. These had been isolated from 114 patients within 10 years in Monterrey, Nuevo Leon, Mexico, known to be endemic for coccidioidomycosis. The gene encoding the specific antigen 2/proline-rich antigen (Ag2/PRA) was used as a target. All strains were correctly identified, whereas DNA from related members of the family Onygenaceae remained negative. Melting curve analysis by LightCycler and sequencing of the 526-bp product of the first PCR demonstrated either 100% identity to the GenBank sequence of the Silveira strain, now known to be C. posadasii (accession number AF013256), or a single silent mutation at position 1228. Length determination of two microsatellite-containing loci (GAC and 621) identified all 120 isolates as C. posadasii. Specific DNA was amplified by conventional nested PCR from three microscopically spherule-positive paraffin-embedded tissue samples, whereas 20 human tissue samples positive for other dimorphic fungi remained negative. Additionally, the safety of each step of a modified commercially available DNA extraction procedure was evaluated by using 10 strains. At least three steps of the protocol were demonstrated to sufficiently kill arthroconidia. This safe procedure is applicable to cultures and to clinical specimens. 相似文献
36.
Differences in virulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men 下载免费PDF全文
Ruiz J Simon K Horcajada JP Velasco M Barranco M Roig G Moreno-Martínez A Martínez JA Jiménez de Anta T Mensa J Vila J 《Journal of clinical microbiology》2002,40(12):4445-4449
Differences in the presence of nine urovirulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men have been studied. Hemolysin and necrotizing factor type 1 occur significantly more frequently among isolates causing prostatitis than among those causing cystitis (P < 0.0001) or pyelonephritis (P < 0.005). Moreover, the papGIII gene occurred more frequently in E. coli isolates associated with prostatitis (27%) than in those associated with pyelonephritis (9%) (P < 0.05). Genes encoding aerobactin and PapC occurred significantly less frequently in isolates causing cystitis than in those causing prostatitis (P < 0.01 and P < 0.0001, respectively) and pyelonephritis (P < 0.01 and P < 0.0001, respectively). No differences in the presence of Sat or type 1 fimbriae were found. Finally, AAFII and Bfp fimbriae are no longer considered uropathogenic virulence factors since they were not found in any of the strains analyzed. Overall, the results showed that clinical isolates producing prostatitis need greater virulence than isolates producing pyelonephritis in women or, in particular, cystitis in women (P < 0.05). Overall, the results suggest that clinical isolates producing prostatitis are more virulent that those producing pyelonephritis or cystitis in women. 相似文献
37.
Oocyte morphology does not affect fertilization rate, embryo quality and implantation rate after intracytoplasmic sperm injection 总被引:6,自引:10,他引:6
Balaban B; Urman B; Sertac A; Alatas C; Aksoy S; Mercan R 《Human reproduction (Oxford, England)》1998,13(12):3431-3433
In this study, we compared the fertilization rate and embryo quality after
intracytoplasmic sperm injection (ICSI) as they relate to oocyte
morphology. A total of 654 ICSI cycles yielding 5903 metaphase II oocytes
were observed. The oocytes retrieved in these cycles were divided into (i)
normal oocytes, (ii) oocytes with extracytoplasmic abnormalities (dark zona
pellucida and large perivitelline space), (iii) oocytes with cytoplasmic
abnormalities (dark cytoplasm, granular cytoplasm, and refractile body),
(iv) oocytes with shape abnormalities, and (v) oocytes with more than one
abnormality (double and triple abnormalities). Intracytoplasmic vacuoles
and aggregates of smooth endoplasmic reticulum were not recorded
separately. The fertilization rate and quality of morphologically graded
embryos did not differ between the groups. There were 77 cycles where all
transferred embryos were derived from abnormal oocytes, and 164 cycles
where all embryos were derived from normal oocytes. These cycles were
studied further. The two groups were comparable regarding mean female age,
duration of infertility, duration of ovarian stimulation, number of
ampoules of gonadotrophin injected, and number of oocytes retrieved. Two
clinical pregnancy rates (44.4 versus 42.1%) and implantation rates per
embryo (10.3 versus 13.2%) were similar. In conclusion, in couples
undergoing ICSI, abnormal oocyte morphology is not associated with a
decreased fertilization rate or unfavourable embryo quality. Furthermore,
embryos derived from abnormal oocytes yield similar clinical pregnancy and
implantation rates when transferred compared with embryos derived from
normal oocytes.
相似文献
38.
We immunohistochemically analyzed cellular apoptosis susceptibility (CAS) protein expression and compared it with 20q13.2 copy number and the expression of cell cycle-associated proteins retinoblastoma (Rb), cyclin D1, and p53 and prognosis on paraffin-embedded tissue from 69 ovarian carcinomas (OCs). CAS protein reactivity was present in 100%, Rb in 54%, cyclin D1 in 47%, and p53 in 49%. Significant reciprocal correlation was observed between high levels of CAS and histologic type, FIGO (International Federation of Obstetrics and Gynecology) stage III and grade 3, residual tumor (>2 cm), 20q13.2 (ZNF217 gene) amplification (>4 copies in >20% cells), and high expression of cyclin D1 (all P < .05). No association was found between cyclin D1, p53, or Rb levels with clinicopathologic factors. In univariate analysis, residual tumor, FIGO stage and grade, ZNF217 amplification, and CAS levels predicted outcome (all P < .05). In multivariate analysis, stage, grade, amount of residual tumor, and ZNF217 amplification showed independent prognostic value (all P < .05). In OC, alteration of CAS and ZNF217 genes, both located at 20q13, is frequent and relevant prognostically. Cyclin D1, Rb, and p53 seem to have a secondary role. 相似文献
39.
Louise Bergeron Gloria I. Perez Glen Macdonald Lianfa Shi Yi Sun Andrea Jurisicova Sue Varmuza Keith E. Latham Jodi A. Flaws Jessica C.M. Salter Hideaki Hara Michael A. Moskowitz En Li Arnold Greenberg Jonathan L. Tilly Junying Yuan 《Genes & development》1998,12(9):1304-1314
During embryonic development, a large number of cells die naturally to shape the new organism. Members of the caspase family of proteases are essential intracellular death effectors. Herein, we generated caspase-2-deficient mice to evaluate the requirement for this enzyme in various paradigms of apoptosis. Excess numbers of germ cells were endowed in ovaries of mutant mice and the oocytes were found to be resistant to cell death following exposure to chemotherapeutic drugs. Apoptosis mediated by granzyme B and perforin was defective in caspase-2-deficient B lymphoblasts. In contrast, cell death of motor neurons during development was accelerated in caspase-2-deficient mice. In addition, caspase-2-deficient sympathetic neurons underwent apoptosis more effectively than wild-type neurons when deprived of NGF. Thus, caspase-2 acts both as a positive and negative cell death effector, depending upon cell lineage and stage of development. 相似文献
40.
Sala G Galimberti G Canevari C Raggi ME Isella V Facheris M Appollonio I Ferrarese C 《Neurobiology of aging》2003,24(7):909-914
Various studies suggested that inflammation is involved in the pathogenesis of Alzheimer's disease (AD). We investigated cytokine release from LPS-stimulated blood cells of 32 AD patients, with different disease severity, compared to 16 age-related controls. A significant decrease of IL-1beta and IL-6 secretion was observed in severely demented patients; TNF-alpha release was also decreased, but not significantly. By contrast, mild and moderate patients showed a cytokine release similar to controls. IL-1beta, IL-6 and TNF-alpha secretion was negatively correlated with the severity of dementia, quantified by the MMSE. Our data suggest that alterations of the immune profile are associated with AD progression. 相似文献