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31.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
32.
Low KG Thoresen CE Pattillo JR King AC Jenkins C 《International journal of behavioral medicine》1994,1(4):305-319
This is an extension of previous research that has reported on psychosocial risk factors in women participants in the Recurrent Coronary Prevention Project (RCPP). The RCPP women (N = 83) were under 65 years of age, non-diabetic, non-smoking and had experienced a myocardial infarction (MI) at least 6 months prior to the study. Baseline data was available on 80 RCPP subjects. Seventy three non-smoking, coronary disease-free women participants in the Stanford-Sunnyvale Health Improvement Project (SSHIP) served as a control-comparison group. Women with coronary heart disease had higher serum cholesterol than controls. There were no case-control differences in marital status, occupation, or number of children. RCPP women had Videotaped Structured Interview (VSI) Type A scores comparable to those of the SSHIP women, but had significantly higher VSI-hostility scores (p < .01). In addition. the post-MI women were rated more anxious and depressed, and had more avoidance symptoms than controls ( p < .01). Additional analyses involved the 65 RCPP women located at 8.5-year follow-up. In these women, univariate predictors of coronary recurrence (N = 13) were body mass index (kg/m)2. Peel Index, low time urgency (VSI) and high anxiety ( p < .05). Employment status, marital status, and education were not associated with subsequent cardiac events. These exploratory analyses suggest that the relations between heart disease and hostility, anxiety, and depression in women deserve further investigation. 相似文献
33.
Use of a selective enrichment broth to recover Clostridium difficile from stool swabs stored under different conditions 下载免费PDF全文
Arroyo LG Rousseau J Willey BM Low DE Staempfli H McGeer A Weese JS 《Journal of clinical microbiology》2005,43(10):5341-5343
The recovery of Clostridium difficile from the stools of patients with C. difficile-associated diarrhea was evaluated by use of an enrichment broth (cycloserine-cefoxitin fructose broth supplemented with 0.1% sodium taurocholate [TCCFB]) and was compared to that from selective agar (cycloserine-cefoxitin fructose agar [CCFA]) and alcohol shock followed by inoculation onto blood agar (AS-BA). TCCFB was superior to CCFA and AS-BA, and neither the storage time nor the storage temperature affected the recovery rate. 相似文献
34.
35.
Role of nitric oxide in the biology, physiology and pathophysiology of reproduction 总被引:13,自引:0,他引:13
Following its benchmark discovery, nitric oxide (NO) is nowknown to play important functional roles in a variety of physiologicalsystems. Within the vasculature, NO induces vasodilation, inhibitsplatelet aggregation, prevents neutrophil/platelet adhesionto endothelial cells, inhibits smooth muscle cell proliferationand migration, regulates programmed cell death (apoptosis) andmaintains endothelial cell barrier function. NO generated byneurons acts as a neurotransmitter, whereas NO generated bymacrophages in response to invading microbes acts as an antimicrobialagent. Because neurons, blood vessels and cells of the immunesystem are integral parts of the reproductive organs, and inview of the important functional role that NO plays in thosesystems, it is likely that NO is an important regulator of thebiology and physiology of the reproductive system. Indeed, inthe past 10 years, NO has established itself as a polyvalentmolecule which plays a decisive role in regulating multiplefunctions within the female as well as the male reproductivesystem. This review provides an overview of the role of NO invarious reproductive organs under physiological and pathologicalconditions. 相似文献
36.
Sandford R; Sgotto B; Aparicio S; Brenner S; Vaudin M; Wilson RK; Chissoe S; Pepin K; Bateman A; Chothia C; Hughes J; Harris P 《Human molecular genetics》1997,6(9):1483-1489
PKD1 is the major locus of the common genetic disorder autosomal dominant
polycystic kidney disease (ADPKD). Analysis of the predicted protein
sequence of the human PKD1 gene, polycystin, shows a large molecule with a
unique arrangement of extracellular domains and multiple putative
transmembrane regions. The precise function of polycystin remains unclear
with a paucity of mutations to define key structural and functional
domains. To refine the structure of this protein we have cloned the genomic
region encoding the Fugu PKD1 gene. Fugu PKD1 spans 36 kb of genomic DNA
and has greater complexity with 54 exons compared with 46 in man.
Comparative analysis of the predicted protein sequences shows a lower level
of homology than in similar studies with identity of 40 and 59% similarity.
However key structural motifs including leucine rich repeats (LRR), a
C-type lectin and LDL-A like domains and 16 PKD repeats are maintained. A
region of homology with the sea urchin REJ protein was also confirmed in
Fugu but found to extend over 1000 amino acids. Several highly conserved
intra- and extra- cellular regions, with no known sequence homologies, that
are likely to be of functional importance were detected. The likely
structure of the membrane associated region has been refined with
similarity to the PKD2 protein and voltage gated Ca2+ and Na+ channels
highlighted over part of this area. The overall protein structure has
therefore been clarified and this comparative analysis derived structure
will form the basis for the functional study of polycystin and its
individual domains.
相似文献
37.
BenMohamed L Krishnan R Longmate J Auge C Low L Primus J Diamond DJ 《Human immunology》2000,61(8):764-779
CTL play a pivotal role in the immune response during viral infections. In this study, the HLA class II restricted T(H) requirement for optimal in vivo induction of HLA class I restricted CTL responses has been investigated. Towards this goal, transgenic mice expressing both HLA class I (A*0201 or A2.1) and class II (DRB1*0101 or DR1) molecules have been derived. Immunization of these mice with an HLA A*0201-restricted and CMV-specific CTL epitope (pp65(495-503)), and either of three different tetanus toxin-derived MHC class II-binding T(H) epitopes, resulted in a vigorous CTL response. CTL specific for the pp65(495-503) epitope were dramatically enhanced in mice expressing both the HLA-DR1 and HLA-A*0201 transgenes. Notably, preinjection of three TT peptides (TT(639-652), TT(830-843), and TT(947-967)) increased the capability of HLA A*0201/DR1 Tg mice to respond to subsequent immunization with the T(H) + CTL peptide mixture. These results indicate that the use of HLA A*0201/DR1 Tg mice constitute a versatile model system (in lieu of immunizing humans) for the study of both HLA class I and class II restricted T-cell responses. These studies provide a rational model for the design and assessment of new minimal-epitope vaccines based on their in vivo induction of a pathogen-specific CTL response. 相似文献
38.
Lai PS Takeshima Y Adachi K Van Tran K Nguyen HT Low PS Matsuo M 《Journal of human genetics》2002,47(10):0552-0555
The frequency and distribution of deletions of 19 deletion-prone exons clustered in two hot spots in the proximal and central
regions of the dystrophin gene were compared in three populations from Singaporean, Japan, and Vietnam. DNA samples obtained
from 105 Singaporean, 86 Japanese, and 34 Vietnamese Duchenne muscular dystrophy patients were examined by polymerase chain
reaction amplification. Deletions of the examined exons were found in 51.2% of Japanese patients but in 40.0% or less of the
Singaporeans and Vietnamese. About two thirds of the deletions were localized in the central region and the remaining deletions
were clustered at the proximal region. The most commonly deleted exons at the central deletion hot spot were exon 50 in the
Singaporean, exons 49 and 50 in the Japanese, and exon 51 in the Vietnamese population. At the proximal deletion hot spot,
the most commonly deleted exons were exons 6 and 8 in the Singaporeans, exons 12 and 17 in the Japanese, and exons 8 and 12
in the Vietnamese. Two cases each from Singapore and Japan had large-scale gross mutations spanning both deletion hot spots.
Our results suggest that, although the presence and frequency of the two deletion hot spots may be similar in the three Asian
populations analyzed, the distribution and frequency of deletions among the different exons can vary as a result of population-specific
intronic sequences that predispose individuals to preferential deletion breakpoints.
Received: May 20, 2002 / Accepted: July 1, 2002 相似文献
39.
40.
Meora Feinmesser Sylvia L. Asa Kaiman Kovacs Bernard A. Roos Malcolm J. Low 《Endocrine pathology》1992,3(1):39-46
Clonal cell lines producing corticotropin-releasing hormone (CRH) have been generated by transfection of the W2 rat medullary
thyroid carcinoma (MTC) cell with a CRH-encoding CMV/ SV40 expression vector. Here, we report the morphological, immunohistochemical,
and ultrastructural features of rat tumors derived by implantation of CRH-producing W2CRH-7 cells and compare them with non-CRH-producing
W2 MTCs. Both types of tumors grew rapidly and consisted of sheets and nests of pleomorphic cells infiltrating adjacent adipose
tissue. Immunohistochemistry revealed CRH in only W2CRH-7 tumors; scattered cells in these tumors also were immunoreactive
for chromogranin and for vasoactive intestinal peptide. Otherwise, the two tumor types exhibited similar profiles of various
neuroendocrine markers, including neuron-specific enolase, synaptophysin, calcitonin, and somatostatin. Ultrastructurally,
the tumors contained abundant dilated rough endoplasmic reticulum, a prominent Golgi apparatus, and numerous lysosomes. Very
few secretory granules were noted in the W2 tumors; by contrast, secretory granules, although still not numerous in the majority
of W2CRH-7 cells, were more abundant in scattered cells of those tumors. The positive immunostaining for CRH is consistent
with the observations of increased plasma CRH and pituitary-adrenal activation induced by these transplanted tumors. This
system provides a valuable model for CRH excess mimicking tumoral CRH-dependent Cushing’s syndrome in human patients. 相似文献