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61.
KF Benson M Horwitz J Wolff K Friend E Thompson S White RI Richards WH Raskind TD Bird 《Canadian Metallurgical Quarterly》1998,7(11):1779-1786
Autosomal dominant familial spastic paraplegia (FSP) is a genetically heterogeneous neurodegenerative disorder displaying anticipation for which three loci have been mapped to the chromosomal positions 14q11.2-q24.3 (SPG3), 2p21-p24 (SPG4) and 15q11.1 (SPG6). The repeat expansion detection (RED) method has been used to demonstrate expanded CAG repeats in some FSP families that map to SPG4. We analyzed 20 FSP families, including four for which there is evidence for linkage to SPG4, and found that in most cases the repeat expansion detected by RED is due to non-pathogenic expansions of the chromosome 18q21.1 SEF2-1 or 17q21.3 ERDA1 locus. Polymorphic expansions at SEF2-1 and ERDA1 appear frequent and may confound RED studies in the search for genes causing disorders demonstrating anticipation. In six FSP families, however, CAG repeat expansion was detected in a subset of affected and at-risk individuals that did not result from expansion of the SEF2-1 and ERDA1 loci. Overall, 11 of 37 (30%) of the FSP patients with a CAG/CTG repeat expansion are unaccounted for by the SEF2-1 and ERDA1 loci, compared with two of 23 (9%) of the unaffected at-risk individuals and none of 19 controls. In the majority of cases these novel expansions were shorter than those previously reported. 相似文献
62.
The B-domain of recombinant human Factor VIII comprises 909 amino acids and is extensively N- and O-glycosylated, in that at least 20 different sites are occupied by numerous carbohydrate structures. This domain was incubated with trypsin and subjected to liquid chromatography electrospray ionization mass spectrometry analysis, using an electrospray orthogonal acceleration time-of-flight mass spectrometer as the detector for a capillary reversed phase HPLC separation of the digest. The inherent high mass resolution afforded by this instrument provides both ion charge state determination and high accuracy mass measurement that are of significant advantage in defining such highly complex mixtures. 相似文献
63.
V Montgomery Rice SD Limback KF Roby PF Terranova 《Canadian Metallurgical Quarterly》1998,13(5):1285-1291
This study determined effects of follicle stimulating hormone (FSH) alone and in combination with tumour necrosis factor (TNF), on granulosa cells from small (5-10 mm diameter) and large (>10-25 mm) follicles during follicular and luteal phases of the cycle and during periods of acyclicity. Granulosa cells were collected from ovaries of premenopausal women undergoing oophorectomy. The cells were cultured with human FSH (2 ng/ml) and testosterone (1 microM) in the presence or absence of human TNF-alpha (20 ng/ml). Media were removed at 48 and 96 h after culture and progesterone, oestradiol and cAMP in media were measured by radioimmunoassays. FSH stimulated the accumulation of oestradiol from granulosa cells of small follicles during the follicular and luteal phases but not during acyclicity; and TNF reduced oestradiol accumulation in the presence of FSH. Interestingly, in granulosa cells from small follicles, progesterone and cAMP secretion increased in response to FSH and neither was affected by TNF. Thus, TNF specifically inhibited the conversion of testosterone to oestradiol in granulosa cells from small follicles. FSH stimulated oestradiol production by granulosa cells of large follicles obtained only during the follicular phase of the cycle and TNF inhibited the FSH-induced oestradiol secretion. Granulosa cells obtained from large follicles during the luteal phase and during acyclicity did not accumulate oestradiol in response to FSH. However, FSH increased progesterone and cAMP secretion by granulosa cells obtained from large follicles during the follicular and luteal phases. During the luteal phase alone, TNF in combination with FSH increased progesterone accumulation above that of FSH alone. FSH did not increase progesterone, oestradiol or cAMP secretion by granulosa cells obtained from large follicles during acyclicity. Thus, FSH increases progesterone, oestradiol and cAMP secretion by granulosa cells of small follicles during the follicular and luteal phases and TNF appears to inhibit FSH-induced oestradiol secretion specifically in those cells. In large follicles, FSH-stimulated granulosa cell secretion of oestradiol is limited to the follicular phase and this effect can be inhibited by TNF. In addition, when granulosa cells of large follicles do not increase oestradiol secretion in response to FSH, TNF stimulates progesterone secretion. 相似文献
64.
B Benari H Kiat J Erel M Hyun FP Wang C Williams JD Friedman G Germano KF Van Train D Berman 《Canadian Metallurgical Quarterly》1995,2(6):478-484
Bacterial antibodies were studied in acute, intermediate and convalescent phase sera (mean duration from first to last sample 36 days) of 121 children hospitalized for acute lower respiratory tract infection. Antibody responses were observed in 45% of all cases and in 29% of the 21 children < 1 year old. A total of 15 responses to Streptococcus pneumoniae (pneumolysin), 20 to Haemophilus influenzae, 9 to Moraxella catarrhalis, 3 to chlamydiae and 8 to Mycoplasma pneumoniae were found. In 79 patients with 4 consecutive samples available, 52% of the 31 responses were measurable within 5 days from admission. Overall the responses were not associated with upper respiratory tract bacterial findings or acute otitis media. Significantly more responses were found in the 121 children with acute lower respiratory tract infection than in healthy controls (P < 0.007). We conclude that bacterial antibody assays provide a useful tool in the study of the etiology of acute lower respiratory tract infection in young children, even if the interval between paired serum samples is short. 相似文献
65.
We report three sibs with mild autosomal recessive variety of osteopetrosis. The prominent clinical features were short stature, malocclusion of teeth, hepatosplenomegaly and a typical facial appearance. The only atypical features were microcephaly, a normal upper segment to lower segment ratio and a normal arm span. 相似文献
66.
During vertebrate development, neuronal survival depends on target-derived neurotrophic factors. Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, can prevent the death of particular peripheral sensory neurons in vitro, and of central motor neurons as well as dopaminergic and cholinergic neurons of the basal forebrain during development. It also prevents the death of motor neurons and midbrain dopaminergic neurons induced by lesions. Here we show that mutant mice lacking BDNF have severe deficiencies in coordination and balance, associated with excessive degeneration in several sensory ganglia including the vestibular ganglion. The few remaining vestibular axons fail to contact the vestibular sensory epithelia, and terminate in the adjacent connective tissue. Survival of sympathetic, midbrain dopaminergic and motor neurons is not affected. These results indicate that BDNF is required for the survival and target innervation of particular neuronal populations. 相似文献
67.
KF Jepsen L Nielsen OT Olsen K Bendtzen LK Poulsen 《Canadian Metallurgical Quarterly》1998,15(3):144-153
Recurrence of membranous nephropathy after renal transplantation has been reported either anecdotally or in a few series. In the present study, the potential risk factors as well as hitherto unreported actuarial risk for recurrence and graft loss due to recurrence were evaluated by combining data of a series of transplanted patients with MN at Louvain Medical School (n = 12) and at Lyon (n = 18; previously reported by Couchoud et al. 1995) giving a total of 30 patients. No risk factor for recurrence was identified as there was no statistical difference between the patients with and without recurrence for duration of MN in native kidneys or of pretransplant hemodialysis, presence of HLA-DR3, graft origin and use of cyclosporin. Actuarial risk for recurrence reached 29% at 3 years, plateauing up to 10 years. The outcome of recurrence was poor since the actual risk for graft loss among patients with recurrent MN was 38 and 52% at 5 and 10 years, respectively. 相似文献
68.
YY Chiang KF Tseng YW Lih TC Tsai CT Liu HK Leung 《Canadian Metallurgical Quarterly》1996,34(4):243-246
One hundred and twenty-six cases of cerebellopontine angle tumors with various histologies are presented. Results of 75 operated vestibular neurinomas, 22 meningiomas, and 16 tumors with other histologies are discussed. The method of irradiation and non-radical surgery may be an alternative for treatment. 相似文献
69.
MG Johnsen KF Appel PL Madsen FK Vogensen K Hammer J Arnau 《Canadian Metallurgical Quarterly》1996,218(2):306-315
Two major structural proteins, MHP (major head protein) and MTP (major tail protein), from the lactococcal temperate phage TP901-1 were sequenced at their amino acid termini, and derived degenerate oligonucleotides were used to locate the corresponding genes in the phage genome. This genomic region was sequenced. The sequence characterized includes a total of 11 open reading frames (ORFs) showing an operon structure. Upstream of each ORF, except ORF b2 and ORF x, potential ribosome-binding sites were found, suggesting independent translation. However, coupled translation is suggested for ORF x and as a possibility for ORF b3 and ORF c2, which have ribosome-binding sites located more distant from their start codons. ORF b2 may be translationally fused with mhp at a low frequency. The mhp and mtp genes are transcribed as a 3.7-kb mRNA with at least six additional ORFs. The organization of the genomic region analyzed resembles that of other distantly related phages, providing possible roles for the uncharacterized ORFs. 相似文献
70.