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31.
Transfer of zona-free embryos improves outcome in poor prognosis patients: a prospective randomized controlled study 总被引:4,自引:0,他引:4
Mansour RT Rhodes CA Aboulghar MA Serour GI Kamal A 《Human reproduction (Oxford, England)》2000,15(5):1061-1064
Assisted zona hatching (AZH) has been used in IVF programmes for several years. Recently one group has reported successful pregnancies after transfer of zona-free blastocysts. The aim of our study was to evaluate outcomes after transfer of zona-free day 3 embryos. Two groups of women undergoing intracytoplasmic sperm injection (ICSI) were included in the study. Group A consisted of 52 women under the age of 40 years undergoing their first ICSI attempt. They were alternately randomized to receive zona-free embryos (27 women) and zona-intact embryos (25 women). The second group (group B) included 71 women with a poor prognosis, as defined by age 40 years or more, and/or at least two previous failed IVF/ICSI attempts. They were randomized in a 3:4 ratio (30 zona-free, 41 zona-intact). Acid Tyrode's solution was used to remove the zona pellucida before embryo transfer on day 3 after oocyte collection. The pregnancy rate in group A was not significantly improved when the zona pellucida was removed. However, in the poor prognosis group B, zona removal resulted in a significantly higher pregnancy rate when compared with controls (23 versus 7.3%). We conclude that complete removal of the zona pellucida can improve pregnancy rates in women with poor IVF/ICSI prognosis. 相似文献
32.
Exponential cultures of Bordetella pertussis strain 18334 were treated with the membrane-perturbing agent phenethyl alcohol which, at a concentration of 0.075% v/v, blocked the synthesis of mature subunit S1 of pertussis toxin as revealed by Western blotting. It also caused the accumulation of a precursor, pS1, with an estimated mol. wt of 32 X 10(3), that was located in the cytoplasmic membrane. These findings suggested that subunit S1 of pertussis toxin was exported in a signal peptide-dependent manner. 相似文献
33.
Rhodopseudomonas sphaeroides lipid A derivatives block in vitro induction of tumor necrosis factor and endotoxin tolerance by smooth lipopolysaccharide and monophosphoryl lipid A. 下载免费PDF全文
B E Henricson P Y Perera N Qureshi K Takayama S N Vogel 《Infection and immunity》1992,60(10):4285-4290
Rhodopseudomonas (Rhodobacter) sphaeroides diphosphoryl lipid A is a relatively inert species of lipid A but has been shown to antagonize the effects of toxic lipopolysaccharide (LPS) both in vivo and in vitro. The antagonist and its monophosphoryl derivative were examined for the ability to block tumor necrosis factor synthesis and reverse tolerance induction in vitro in macrophage cultures stimulated with bioactive preparations of smooth LPS, rough LPS, diphosphoryl lipid A, and monophosphoryl lipid A. Inhibition of agonist activity and reversal of tolerance by these novel penta-acylated lipid A antagonists provides new insight into macrophage-LPS interactions. 相似文献
34.
A synthetic nanofibrillar matrix promotes in vivo-like organization and morphogenesis for cells in culture 总被引:7,自引:0,他引:7
Schindler M Ahmed I Kamal J Nur-E-Kamal A Grafe TH Young Chung H Meiners S 《Biomaterials》2005,26(28):5624-5631
The purpose of this study was to design a synthetic nanofibrillar matrix that more accurately models the porosity and fibrillar geometry of cell attachment surfaces in tissues. The synthetic nanofibrillar matrices are composed of nanofibers prepared by electrospinning a polymer solution of polyamide onto glass coverslips. Scanning electron and atomic force microscopy showed that the nanofibers were organized into fibrillar networks reminiscent of the architecture of basement membrane, a structurally compact form of the extracellular matrix (ECM). NIH 3T3 fibroblasts and normal rat kidney (NRK) cells, when grown on nanofibers in the presence of serum, displayed the morphology and characteristics of their counterparts in vivo. Breast epithelial cells underwent morphogenesis to form multicellular spheroids containing lumens. Hence the synthetic nanofibrillar matrix described herein provides a physically and chemically stable three-dimensional surface for ex vivo growth of cells. Nanofiber-based synthetic matrices could have considerable value for applications in tissue engineering, cell-based therapies, and studies of cell/tissue function and pathology. 相似文献
35.
Granulomatous Pneumocystis carinii pneumonia complicating hematopoietic cell transplantation 总被引:1,自引:0,他引:1
Gal AA Plummer AL Langston AA Mansour KA 《Pathology, research and practice》2002,198(8):553-8; discussion 559-61
Pneumocystis carinii pneunonia (PCP) is associated with a wide spectrum of clinical and histopathological presentations. While granulomatous PCP uncommonly occurs in AIDS patients, it is extremely rare in other non-AIDS immunocompromised patients. We identified three patients who developed granulomatous PCP after bone marrow or blood stem cell transplantation. In all cases, fiberoptic bronchoscopy with bronchoalveolar lavage was non-diagnostic, and an open lung biopsy was required for diagnosis. All patients were successfully treated with trimethoprim-sulfamethoxazole. The histological appearance varied from an ill-defined granulomatous pneumonia to well-formed necrotizing granulomas. The typical intraalveolar eosinophilic frothy exudate was absent. Often sparsely distributed, the organisms were detected by GMS and immunohistochemical stains for P. carinii. No other pathogens were identified by additional histochemical stains or by microbiological cultures. Awareness of this unusual granulomatous tissue response to P. carinii and initiation of specific treatment can lead to successful resolution of this potentially lethal infection. 相似文献
36.
Fahmy I Kamal A Shamloul R Mansour R Serour G Aboulghar M 《Human reproduction (Oxford, England)》2004,19(7):1558-1561
BACKGROUND: The aim of this study was to assess the use of testicular sperm for ICSI in azoospermic men with hypogonadotrophic hypogonadism unresponsive to gonadotrophin therapy. METHODS: Fifteen patients with hypogonadotrophic hypogonadism who remained azoospermic after hormonal treatment underwent testicular sperm extraction (TESE) and ICSI. These men were recruited from the Egyptian IVF centre over a period of 4 years. All patients were given 75 IU hMG thrice weekly and 5000 IU hCG once or twice weekly for >/=6 months prior to attempting ICSI/TESE. RESULTS: In 11 out of 15 patients (73%), sperm could be retrieved from testicular tissue and were used for ICSI. Two chemical pregnancies resulted but no clinical pregnancies. Nine patients continued gonadotrophin therapy for another 6 months. Sperm appeared in the ejaculate of three of them. The remaining six patients underwent another ICSI cycle, one using cryopreserved sperm and five underwent a second TESE. One chemical pregnancy and three clinical pregnancies were established. One ongoing, one singleton and one twin pregnancies resulted in the delivery of three healthy babies. In total, of 17 ICSI cycles performed using testicular sperm retrieval, the fertilization rate was 41.7% and the cumulative pregnancy rate was 20%. CONCLUSIONS: The use of testicular sperm for ICSI is a treatment option that can be offered to azoospermic males with hypogonadotrophic hypogonadism either not responding or reluctant to continue hormonal treatment. However, prolonged hormonal treatment may improve TESE/ICSI results. 相似文献
37.
38.
Use of Antibodies in Lymphocyte Secretions for Detection of Subclinical Tuberculosis Infection in Asymptomatic Contacts 下载免费PDF全文
Rubhana Raqib S. M. Mostafa Kamal M. Jubayer Rahman Zeaur Rahim Sayera Banu Pradip K. Bardhan Fahima Chowdhury Gul Ara K. Zaman Robert F. Breiman Jan Andersson David A. Sack 《Clinical and Vaccine Immunology : CVI》2004,11(6):1022-1027
We have previously demonstrated that Mycobacterium bovis BCG-specific immunoglobulin G antibodies in lymphocyte secretions (ALS) can be employed as a marker for active tuberculosis (TB). We aimed to determine whether the ALS method allows detection of subclinical TB infection in asymptomatic individuals. A prospective study of family contacts (FCs) of patients with active TB and healthy controls was performed. Thirteen of 42 FCs had high ALS responses, including 6 FCs who subsequently developed active TB. No correlation was observed between the tuberculin skin test and the ALS responses in the FCs (r = 0.1, P = 0.23). Among patients with active TB, BCG-specific ALS responses steadily declined from the time of diagnosis through 6 months following antimycobacterial chemotherapy (P = 0.001). The ALS assay enabled detection of infection in exposed symptom-free contacts, who are at greater risk for developing active TB. The method may also allow discrimination between effective treatment of active infection and suboptimal response to therapy. 相似文献
39.
K. Alsaeid M. Z. Haider H. Kamal B. S. Srivastva E. M. Ayoub 《International journal of immunogenetics》2002,29(1):1-5
The prevalence of human leukocyte antigen (HLA) DR alleles has been determined in 69 Kuwaiti Arab children with juvenile rheumatoid arthritis (JRA) and compared to that in 212 ethnically matched normal healthy controls using a PCR–sequence specific primers (PCR‐SSP) method. A very high incidence of DR3 was detected in JRA patients compared to the controls (P < 0.0001, RR = 2.235). The high incidence of HLA‐DR3 in JRA patients was accounted for mainly by an excess of DRB1*0307 (P < 0.05, RR = 3.072) and DRB1*0308 (P < 0.009, RR = 2.663) compared to the controls. Moreover, DR3 was more prevalent when patients with ANA‐positive JRA were analysed separately; 73% compared to 58% for the whole JRA patient group. The frequency of DR1 was also higher in the JRA group compared to controls (P = 0.019, RR = 3.585). Although the incidence of some alleles was higher in the control group (DR13 and DR7), none reached a statistically significant level. All the patients with iridocyclitis had either a DR1 or DR3 allele, except for one child. The frequency of DRB1*03 was found to be much higher in the polyarticular subtype of Kuwaiti JRA cases compared to the oligoarticular subgroup and the controls. Also, a non‐significant increase in the frequency of the DRB1*04, *11 and *15 alleles was detected in the polyarticular subtype of the Kuwaiti JRA cases compared to the controls. 相似文献
40.