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91.
Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer. 相似文献
92.
DP McHale S Mitchell S Bundey L Moynihan DA Campbell CG Woods NJ Lench RF Mueller AF Markham 《Canadian Metallurgical Quarterly》1999,64(2):526-532
Cerebral palsy has an incidence of approximately 1/500 births, although this varies between different ethnic groups. Genetic forms of the disease account for approximately 1%-2% of cases in most countries but contribute a larger proportion in populations with extensive inbreeding. We have clinically characterized consanguineous families with multiple children affected by symmetrical spastic cerebral palsy, to locate recessive genes responsible for this condition. The eight families studied were identified from databases of patients in different regions of the United Kingdom. After ascertainment and clinical assessment, we performed a genomewide search for linkage, using 290 polymorphic DNA markers. In three families, a region of homozygosity at chromosome 2q24-q25 was identified between the markers D2S124 and D2S148. The largest family gave a maximum LOD score of 3.0, by multipoint analysis (HOMOZ). The maximum combined multipoint LOD score for the three families was 5.75. The minimum region of homozygosity is approximately 5 cM between the markers D2S124 and D2S2284. We have shown that a proportion of autosomal recessive symmetrical spastic cerebral palsy maps to chromosome 2q24-25. The identification of genes involved in the etiology of cerebral palsy may lead to improved management of this clinically intractable condition. 相似文献
93.
A Carrello E Ingley RF Minchin S Tsai T Ratajczak 《Canadian Metallurgical Quarterly》1999,274(5):2682-2689
Structurally related tetratricopeptide repeat motifs in steroid receptor-associated immunophilins and the STI1 homolog, Hop, mediate the interaction with a common cellular target, hsp90. We have identified the binding domain in hsp90 for cyclophilin 40 (CyP40) using a two-hybrid system screen of a mouse cDNA library. All isolated clones encoded the intact carboxyl terminus of hsp90 and overlapped with a common region corresponding to amino acids 558-724 of murine hsp84. The interaction was confirmed in vitro with bacterially expressed CyP40 and deletion mutants of hsp90beta and was delineated further to a 124-residue COOH-terminal segment of hsp90. Deletion of the conserved MEEVD sequence at the extreme carboxyl terminus of hsp90 precludes interaction with CyP40, signifying an important role for this motif in hsp90 function. We show that CyP40 and Hop display similar interaction profiles with hsp90 truncation mutants and present evidence for the direct competition of Hop and FK506-binding protein 52 with CyP40 for binding to the hsp90 COOH-terminal region. Our results are consistent with a common tetratricopeptide repeat interaction site for Hop and steroid receptor-associated immunophilins within a discrete COOH-terminal domain of hsp90. This region of hsp90 mediates ATP-independent chaperone activity, overlaps the hsp90 dimerization domain, and includes structural elements important for steroid receptor interaction. 相似文献
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96.
M Aristegui RF Canalis M Naguib E Saleh Y Cokkeser F Mancini M Sanna 《Canadian Metallurgical Quarterly》1997,76(8):578-583
We report our experience (1987-1993) with Meniere's disease patients treated with a retrolabyrinthine vestibular neurectomy. The current literature was reviewed and our results have been compared with those of previous reports. The overall success rate for vertigo relief was 96.7%, with no serious or permanent complications resulting from the procedure. The technical elements of the operation, as they apply to our approach and those of others, have been analyzed, with special attention given to the anatomical features of the region and their influence on success or failure. We conclude that the retrolabyrinthine approach for vestibular nerve section remains a safe and highly successful technique which merits continued use. 相似文献
97.
M van der Gaag AJ Debets HD Osiewacz RF Hoekstra 《Canadian Metallurgical Quarterly》1998,258(5):521-529
We have investigated the properties of the newly synthesized proton-pump inhibitor, 3-butyryl-8-methoxy-4-[(2-thiophenyl)amino]quinoline (YJA20379-6), on gastric mucosal proton-pump (H+/K+-ATPase) activity, gastric acid secretion and gastroduodenal lesions in experimental rats. YJA20379-6 markedly inhibited H+/K+-ATPase activity in rabbit isolated gastric mucosal microsomes, confirming its classification as a proton-pump inhibitor. The inhibitory efficacy of YJA20379-6 on the proton pump was approximately 14-times higher than that of omeprazole at pH 7.4. YJA20379-6 given intraduodenally had a potent inhibitory effect on gastric secretion in pylorus-ligated rats (ED50 22.9 mg kg(-1)) but was less active than omeprazole. Pretreatment of rats with YJA20379-6 dose-dependently protected the gastric mucosa from damage induced by water-immersion stress, indomethacin and absolute ethanol, and the duodenal mucosa from damage induced by mepirizole. Repeated administration of YJA20379-6 also dose-dependently accelerated the spontaneous healing of acetic acid-induced gastric ulcers. These results suggest that YJA20379-6 has potent anti-secretory and anti-ulcer effects which are exerted by suppression of H+/K+-ATPase activity in gastric parietal cells. YJA20379-6 might be useful for the clinical treatment of peptic ulcer diseases. 相似文献
98.
RE Marc RF Murry SK Fisher KA Linberg GP Lewis M Kalloniatis 《Canadian Metallurgical Quarterly》1998,39(9):1685-1693
PURPOSE: To establish a nomogram of amino acid signatures in normal neurons, glia, and retinal pigment epithelium (RPE) of the cat retina, guided by the premise that micromolecular signatures reflect cellular identity and metabolic integrity. The long-range objective was to provide techniques to detect subtle aberrations in cellular metabolism engendered by model interventions such as focal retinal detachment. METHODS: High-performance immunochemical mapping, image registration, and quantitative pattern recognition were combined to analyze the amino acid contents of virtually all cell types in serial 200-nm sections of normal cat retina. RESULTS: The cellular cohorts of the cat retina formed 14 separable biochemical theme classes. The photoreceptor --> bipolar cell --> ganglion cell pathway was composed of six classes, each possessing a characteristic glutamate signature. Amacrine cells could be grouped into two glycine- and three gamma-aminobutyric acid (GABA)-dominated populations. Horizontal cells possessed a distinctive GABA-rich signature completely separate from that of amacrine cells. A stable taurine-glutamine signature defined Müller cells, and a broad-spectrum aspartate-glutamate-taurine-glutamine signature was present in the normal RPE. CONCLUSIONS: In this study, basic micromolecular signatures were established for cat retina, and multiple metabolic subtypes were identified for each neurochemical class. It was shown that virtually all neuronal space can be accounted for by cells bearing characteristic glutamate, GABA, or glycine signatures. The resultant signature matrix constitutes a nomogram for assessing cellular responses to experimental challenges in disease models. 相似文献
99.
100.
D Olde Weghuis ME Stoepker B de Leeuw E van den Berg RF Suijkerbuijk WM Molenaar B de Jong A Geurts van Kessel 《Canadian Metallurgical Quarterly》1994,9(4):288-291
In this case-control study, we investigated the role of Cryptosporidium in gastroenteritis in children < 6 years old. Six hundred fresh stool specimens were examined for various pathogenic parasites, bacteria, and rotaviruses. Wet-mount preparations, formaline-ether concentrations, and Sheather's floatation techniques were used to recover the parasite oocysts. Permanent stained slides using acid-fast stain and trichrome stains were prepared. Of 300 children with gastroenteritis symptoms, 20 (6.7%) had Cryptosporidium oocysts; seven of the 20 had concomitant infections so they were excluded from the counts. This infection rate is significantly different (Z = 2; p < 0.05) from that found in the control group (1.7%) of children who reported no symptoms. The most frequent symptoms reported beside diarrhea were abdominal pain, cramps, anorexia, nausea, vomiting, and fatigue. Contaminated drinking water is suspected to be the source of infection; other possible factors are discussed. 相似文献