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191.
Relationship between ROS production, apoptosis and DNA denaturation in spermatozoa from patients examined for infertility 总被引:24,自引:0,他引:24
Moustafa MH Sharma RK Thornton J Mascha E Abdel-Hafez MA Thomas AJ Agarwal A 《Human reproduction (Oxford, England)》2004,19(1):129-138
BACKGROUND: The aim of this study was to examine the role of apoptosis and reactive oxygen species (ROS) in inducing DNA damage in ejaculated spermatozoa. METHODS: We examined ejaculated spermatozoa from 31 patients examined for infertility and 19 healthy donors for apoptosis, production of ROS and DNA damage using annexin V binding, chemiluminescence assay and sperm chromatin structure assay. RESULTS: The percentage of spermatozoa that underwent apoptosis in the whole ejaculate and mature fraction was higher in the patients than in the donors (P<0.001 and P=0.009, respectively). Levels of ROS in the whole ejaculate and immature fraction were higher in the patients than in the donors (P=0.002 and P=0.009). Apoptosis was significantly correlated with ROS within patients in the whole ejaculate [r (95% confidence interval)=0.53 (0.19-0.86)] and in the mature [0.71 (0.39-1.00)] and immature spermatozoa [0.75 (0.45-1.00)]. Only apoptosis and the DNA fragmentation index (DFI) were significantly correlated within patients in the whole ejaculate [0.57 (0.18-0.97)]. CONCLUSIONS: DNA damage may be induced by oxidative assault. Apoptosis may not contribute significantly to the DNA damage. 相似文献
192.
Anuradha Chowdhary H S Randhawa Sonal Sharma Mary E Brandt Sunil Kumar 《Medical mycology》2005,43(1):87-90
The etiologic role of Malassezia furfur in onychomycosis is a contentious diagnostic problem because its keratinolytic ability has never been verified. This case report describes the isolation of M. furfur from the infected nails of a child clinically diagnosed with onychomycosis, and discusses the role of this organism as an etiologic agent/colonizer. The patient presented with subungual hyperkeratosis and onycholysis without associated paronychia. Budding yeast cells compatible with M. furfur were repeatedly demonstrated in KOH wet mounts of damaged nails, histopathology of hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) stained sections showed penetration of fungal elements between deeper layers of keratin, and numerous colonies of M. furfur were isolated on three consecutive occasions from nail specimens collected from different areas of hand and toenail lesions. No evidence of nail invasion by dermatophytic or nondermatophytic filamentous fungi were found by direct microscopy or culture. Microscopy and culture were negative following 12 weeks of ketoconazole treatment, which resulted in growth of healthy nail plates with normal beds. We can infer from these observations that M.furfur was an etiologic agent rather than a colonizer in the patient's nails even though direct keratinolytic character of this fungus was not demonstrated. 相似文献
193.
V Kochupillai S Sharma S Francis A Nanu S Mathew P Bhatia H Dua L Kumar S Aggarwal S Singh 《Thymus》1987,10(1-2):95-102
Forty patients with severe aplastic anaemia received an intravenous infusion of 0.004 to 11.1 x 10(8) (median: 8 x 10(8) hematopoietic cells prepared from the fetal livers of 8-32 week old abortuses. Five patients, who died within 15 days of fetal liver infusion, are excluded from analysis. Twenty-two of the 35 evaluable patients (62%) responded favourably. Six of the 7 patients with good response were alive after 9 to 44 months (median: m = 20); one died 106 months after fetal liver infusion due to renal lithiasis. Four of the 7 with moderate response were alive after 9 to 31 months; 3 died within 16 months. Of 8 patients with minimal response, one was lost to follow-up and the others died in 3.4 to 10 months (m = 6). Median survival of responders was 15.7 months. Bone marrow cellularity became normal in 12 patients following fetal liver infusion. In seven patients, there was a relapse; 6 regained a normal bone marrow cellularity after a second or third fetal liver infusion. These data strongly suggest a role of fetal liver infusion in inducing bone marrow recovery. Of 13 non-responders, 4 were lost to follow-up and 9 died within 20 days-4.3 months (m = 1.6). Fetal liver infusion appears to be an effective therapy in patients with severe aplastic anaemia. 相似文献
194.
An unusual giant cell tumor of the breast of a 72 year old man is reported. The microscopic and ultrastructural features of the tumor are presented in detail. Unusual and previously unreported myofibroblastic and myoepithelial differentiation of the spindle cell component is described. The possible histogenesis of the tumor is discussed. 相似文献
195.
A Vazquez M T Auffredou N Chaouchi J Taieb S Sharma P Galanaud G Leca 《European journal of immunology》1991,21(10):2311-2316
Surface immunoglobulin (Ig) cross-linking by anti-IgM (mu) antibodies leads to B cell activation resulting in numerous early biochemical events including an increase in intracellular [Ca2+]. Furthermore, anti-mu-activated B cells become able to proliferate in response to interleukin (IL)2 and IL4. These studies examined the effect of the calcium ionophore ionomycin, an enhancer of cytoplasmic [Ca2+] levels, on IL2 and IL4-mediated proliferation of anti-mu-stimulated normal human B cells. Ionomycin inhibited the proliferative response of anti-mu-activated B cells to IL4. In contrast, IL2 and phorbol 12,13 dibutyrate (PBu2)-mediated B cell proliferation was refractory to the growth inhibitory effects of ionomycin. In an attempt to delineate a possible mechanism(s) for this differential growth effect of ionomycin, we first studied direct effects of ionomycin on activated B cells. Our data suggested that ionomycin induced DNA fragmentation in anti-mu-costimulated B cells. Interestingly, in contrast to PBu2, IL4 did not prevent ionomycin-dependent DNA fragmentation. Importantly, H7, an inhibitor of protein kinase C activation, down-regulated only the IL2 and PBu2-driven B cell proliferation but not B cell proliferative response to IL4. These results suggest that putative protein kinase C activation, either by direct treatment with phorbol ester or during IL2 signaling, counteracts the inhibitory effects of ionomycin. In contrast, IL4 signaling does not exhibit the same protective properties. 相似文献
196.
197.
The t(1;19)(q23;p13) has been reported in up to 6% of cytogenetically abnormal cases of acute lymphoblastic leukaemia (ALL), associated with a pre-B-ALL phenotype. In the 5-year period 1995-1999, we detected t(1;19) in 13 children and 2 adults with newly diagnosed ALL. This represented 10% of pediatric and 2.5% of adult diagnostic ALL samples successfully cultured in one center during this time. There were 9 males and 6 females. The mean age at diagnosis for the 13 children was 6.5 years (range 1.5 to 14 years) and the 2 adults were aged 42 and 45 years. The unbalanced t(1;19) occurred in 7 of 13 children (54%), contrary to the reported excess of unbalanced translocations at 75%; both adults had the unbalanced translocation. At diagnosis, the t(1;19) was the sole abnormality in 4 patients (26%), and in the remainder (74%) was part of a complex karyotype, which included i(7q) (2 patients), hyperdiploidy (2 patients) and del(6q) (2 patients). Correlation of karyotype with white cell, blast and platelet counts, cell surface markers, initial response to chemotherapy and short-term outcome showed no difference between the balanced and unbalanced forms of the translocation in children or whether t(1;19) was present as the sole abnormality or part of a complex karyotype. 相似文献
198.
The first case of cryptococcosis caused by Cryptococcus neoformans var. grubii in a new species of bandicoot (Bandicota indica) is described. The animal was trapped in a bamboo thicket in a park located in the city of Jabalpur, India. On necropsy, pathological lesions were seen in the lungs and liver and C. neoformans var. grubii was isolated from the lungs, liver, kidneys, spleen and brain but not the heart or intestine. The soil of the animal's burrow and bamboo debris around it also revealed the presence of C. neoformans var. grubii. We hypothesize that the bandicoots may potentially act as sentinel animals for environmental human pathogenic Cryptococcus species. 相似文献
199.
The 2.311 kb EcoRI F fragment of bacteriophage MB78 has been cloned in multicopy vectors pUC19 and pCR90. Salmonella typhimurium strains carrying such plasmids cannot support development of phage MB78 while other Salmonella phages like P22 and 9NA grow normally. Most of the phage MB78 induced functions are normal in such transformed hosts but proper maturation of the phage particles does not take place. Deletion of 138 bp from the 3 end of the cloned fragment reverses the inhibitory effect. Analysis of nucleotide and the deduced amino acid sequence of a 1.2 kb HindIII-SalI fragment of the phage genome which overlaps the 138 bp confirms that this part contains the upstream regulatory region of the major structural protein gene. It seems that in presence of multiple copies of the upstream regulatory region (which includes a number of promoter like sequence) of the coat protein gene, the maturase gene is down regulated and this is effective only in cis, a situation quite similar to that of Q RNA phages. 相似文献
200.
Summary Biochemical studies on the two transaminases GOT and GPT of swine kidney worm Stephanurus dentatus have been made. GOT has been found much more active than GPT. Enzyme activities are based on the formation of oxaloacetate (GOT) or pyruvate (GPT) from aspartic acid and alanine respectively with oxoglutarate. A linear relationship is observed between the enzyme concentration and activity. GOT shows a maximum activity at pH 8.0 and Michaelis constant 9×10–3 M for male and 2.9×10–3 M for female. GPT has an optimum pH of 7.5 and a Michaelis constant 19×10–3 M for male and 8×10–3 M for female. The optimum temperature for both GOT and GPT was 60° C. 相似文献