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21.
Successful outcome with day 4 embryo transfer after preimplantation diagnosis for genetically transmitted diseases 总被引:4,自引:5,他引:4
Preimplantation genetic diagnosis was performed in 61 day 3 embryos
obtained by in-vitro fertilization from seven patient carriers of
haemophilia, Marfan's syndrome, Bloch-Sulzemberg syndrome (incontinentia
pigmentosa) or X chromosome-linked immune deficiency, retinitis pigmentosa,
and FG syndrome, which is characterized by mental retardation and
hypotonia. After multiplex polymerase chain reaction, 16 embryos were
diagnosed as being unaffected, and these were transferred to the uterus on
the following day (day 4). Of these embryos, six (37.5%) implanted,
resulting in the delivery of a singleton and a twin pregnancy, a late
second trimester miscarriage (twins at week 20) and a first trimester
miscarriage at week 8. All the diagnoses were confirmed by amniocentesis.
We report for the first time a late day 4 transfer of biopsied human
embryos undergoing preimplantation genetic diagnosis. This transfer
schedule allows an extra day to perform genetic analyses on single
blastomeres and to monitor any adverse effect of the biopsy procedure.
相似文献
22.
Marjolijn Bornebroek Joost Haan Marion LC Maat-Schieman Sjoerd G Van Duinen Raymund AC Roos 《Brain pathology (Zurich, Switzerland)》1996,6(2):111-114
Hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) is an autosomal dominant disease caused by deposition of β-amyloid in the leptomeningeal arteries and cortical arterioles, in addition to preamyloid deposits and amyloid plaques in the brain parenchyma.
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article 相似文献
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article 相似文献
23.
Detection of Norwalk Virus and Other Genogroup 1 Human Caliciviruses by a Monoclonal Antibody, RecombinantAntigen-Based Immunoglobulin M Capture Enzyme Immunoassay
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James P. Brinker Neil R. Blacklow Mary K. Estes Christine L. Moe Kellogg J. Schwab John E. Herrmann 《Journal of clinical microbiology》1998,36(4):1064-1069
Sera obtained from two groups of adult volunteers infected with Norwalk virus (NV) and two groups of patients involved in two natural outbreaks were tested for NV-reactive immunoglobulin M (IgM) by use of a monoclonal antibody, recombinant-antigen-based IgM capture enzyme immunoassay (EIA). No NV-reactive IgM was detected in the preinoculation sera of 15 volunteers, and 14 of 15 showed NV-reactive antibodies postinfection with NV. All of the volunteers showed IgG seroconversion to NV. In the outbreak studies, all 9 persons in one outbreak and 19 of 24 in another outbreak had NV-reactive IgM. In the first outbreak, only three of nine seroconverted to NV, which was likely due to late collection of acute-phase sera. In the second outbreak, 21 of 24 showed IgG seroconversion to NV. Sequencing of viruses isolated from five stool samples selected from those in the second outbreak showed that they were human calicivirus (HuCV) genogroup 1 viruses related, but not identical, to NV. In the volunteer studies, NV-reactive IgM was first detected 8 days postinoculation. The time of development of NV-reactive IgM antibodies in natural outbreaks was estimated to be similar to that found in the volunteer studies. Sera from three Hawaii virus-infected volunteers, four Snow Mountain virus patients, and 80 healthy individuals were negative for NV-reactive IgM, indicating test specificity for HuCV genogroup I infections. This capture IgM EIA is suitable for diagnosis of NV and other HuCV genogroup I infections and is especially useful when sera and fecal samples have not been collected early in the course of an outbreak. 相似文献
24.
Functional activity of anti-Neisserial surface protein A monoclonal antibodies against strains of Neisseria meningitidis serogroup B 总被引:6,自引:0,他引:6
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Neisserial surface protein A (NspA) is currently being investigated with humans as a candidate vaccine for the prevention of meningococcal disease. Although NspA is highly conserved, the ability of anti-NspA antibodies to bind to or elicit complement-mediated bactericidal activity against diverse Neisseria meningitidis serogroup B strains is controversial. To evaluate strain differences in NspA surface accessibility and susceptibility to bactericidal activity, we prepared murine immunoglobulin G2a anti-NspA monoclonal antibodies (MAbs) and evaluated their functional activity against 10 genetically diverse N. meningitidis serogroup B strains. By colony Western blot, all 10 strains expressed NspA as detected by one or more MAbs. By flow cytometry, two MAbs were found to bind to the bacterial surface of 6 of the 10 strains. In addition, two strains showed variable NspA surface accessibility for the MAbs despite being uniformly positive for NspA expression by colony Western blotting. Only 4 of the 10 strains were susceptible to anti-NspA complement-mediated bacteriolysis. Passively administered MAb protected infant rats from developing bacteremia after challenge with N. meningitidis serogroup B strain 8047 (surface binding positive, susceptible to anti-NspA bacteriolysis), was poorly protective against strain BZ232 (surface binding variable, resistant to bacteriolysis), and did not protect against strain M986 (surface binding negative, resistant to bacteriolysis). Finally, NspA does not appear to be critical for causing bacteremia, as an NspA knockout from strain 8047 was highly virulent in infant rats. Taken together, these findings suggest that an NspA-based vaccine will need to incorporate additional antigens to elicit broad protection against N. meningitidis serogroup B. 相似文献
25.
Isolation and characterization of brush border membrane vesicles from bovine small intestine 总被引:1,自引:0,他引:1
Intestinal brush border membrane vesicles were prepared from 21-wk-old Holstein bulls. The method of preparation included magnesium precipitation, differential centrifugation and sucrose density gradient centrifugation. Purification of brush border membranes was indicated by sevenfold enrichment of alkaline phosphatase activity. Uptake of D-[U-14C]glucose was sodium-stimulated and exhibited characteristic "overshoot" phenomenon. Sodium-dependent and sodium-independent D-glucose uptake was into an osmotically active space. Phloridzin (100 mM) completely inhibited sodium-dependent, but did not affect sodium-independent transport. Sodium-dependent D-glucose transport was inhibited more by D-glucose than by D-galactose, which inhibited more than D-xylose did. The sodium-dependent D-glucose transport was not inhibited by D-fructose, D-ribose or D-arabinose. Sodium-independent D-glucose transport was unaffected by the sugars tested. Glucose transport in bovine intestinal brush border is similar to that in monogastric species and is composed of two pathways: a sodium-dependent inhibitable system and a diffusional system. 相似文献
26.
Sophie D. Fosså Asbjørn Flokkmann Mona Heier Magne Aas Brit Moe R. Heintz Sheila Linder-Ciccolunghi 《Cancer chemotherapy and pharmacology》1986,18(3):252-256
Summary Eighteen patients with advanced solid cancer were treated with daily 5-dFUrd infusions given over 1 h on days 1–5 of a 4-week cycle. Nine patients received 3 g/m2 5-dFUrd daily and another nine patients 5 g/m2. One patient on 5 g/m2 5-dFUrd was not fully evaluable for tolerability due to early death (progressive disease) 4 weeks after the first cycle. A total of 48 cycles was given. The gastrointestinal and hematological toxicity was generally mild (grade 1–2). Central neurotoxicity (ataxia, unsteadiness, diplopia, dysarthria, sometimes confusion) was observed in 7 of 8 patients on 5 g/m2 5-dFUrd leading to premature discontinuation of treatment in 3 patients (after 2 cycles). Only 3 of the 9 patients in the 3 g/m2 group had slight signs of cerebellopathy. Typically, the reversible neurological side effects started at the end of the 2nd week of a cycle. The serum elimination kinetics of 5-dEUrd and its metabolites 5-FU and 5-dFUH2 have been investigated in the serum and showed very low intra- and interindividual variations. Peak concentrations of the 5-dFUrd at the end of the infusion approximated 500 mol/l and 1000 mol/l for the 3 g/m2 and 5 g/m2 group, respectively. The peak of the serum 5-FU was reached at the same time, the ratio 5-FU/5-dFUrd being around 10%. The elimination half-life time for 5-FU was protracted by a factor of 2–3 compared with the direct injection of 5-FU.Monthly infusion of 5-dFUrd 5 mg/m2 per day on days 1–5 lead to an unacceptable frequency and degree of neurological toxicity. Similar infusions of 5-dFUrd 3 g/m2 per day on days 1–5 were well tolerated. 相似文献
27.
28.
同种异体黑素细胞移植治疗白癜风 总被引:2,自引:2,他引:0
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小… 相似文献
29.
30.
Diarrheal deaths in the United States, 1979 through 1987. A special problem for the elderly 总被引:3,自引:0,他引:3
OBJECTIVE.--Diarrhea is an important cause of death among young children in both developing and developed countries, but little is known about diarrheal death among adults. In this study, we examined trends in diarrheal deaths among all age groups in the United States. DESIGN/SETTING/PARTICIPANTS.--We reviewed national mortality data complied by the National Center for Health Statistics, Hyattsville, Md, which consists of information from all death certificates filed in the United States for the period 1979 through 1987. A death for which diarrhea was listed as an immediate or underlying cause was considered a "diarrheal death" and included in the analysis. RESULTS.--We found that 28,538 persons died of diarrhea cited as either an immediate or the underlying cause of death during the 9-year period. A majority of diarrheal deaths occurred among the elderly (older than 74 years of age, 51%), followed by adults 55 to 74 years of age (27%), and young children (younger than 5 years of age, 11%). For the elderly, adjusted risk factors for dying of diarrhea included being white, female, and residing in a long-term care facility. Only the elderly and young children had clear, distinct winter peaks of diarrheal deaths, suggesting that the diarrhea may, in part, be infectious in origin. CONCLUSION.--For the elderly, more directed studies of those at risk, such as nursing home residents, are needed to determine if oral rehydration therapy, vaccines, or other preventive measures might benefit this population. 相似文献