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RF Ghohestani JF Nicolas P Rousselle AL Claudy 《Canadian Metallurgical Quarterly》1997,133(9):1102-1107
OBJECTIVE: To determine the diagnostic value of indirect immunofluorescence on sodium chloride-split skin (SSS) in differentiating the pemphigoid group of subepidermal autoimmune bullous dermatoses, including bullous pemphigoid (BP), cicatricial pemphigoid, and pemphigoid gestationis, from epidermolysis bullosa acquisita (EBA). DESIGN: Serum samples were tested using immunofluorescence on SSS and immunoblot assay on epidermal and dermal extracts, a recombinant protein corresponding to the C-terminal end of the 230-kd BP antigen, and purified laminin-5. SETTING: An immunodermatology laboratory. PATIENTS: One hundred forty-two serum samples from patients with BP (n = 98), cicatricial pemphigoid (n = 23), pemphigoid gestationis (n = 10), EBA (n = 10), and anti-type IV collagen (n = 1). MAIN OUTCOME MEASURES: Binding sites of serum to the epidermal and/or dermal sides of SSS were correlated with their antigenic specificities. RESULTS: Epidermal staining on SSS was highly specific for pemphigoid. Alternatively, a poor correlation was found for the dermal-reacting serum samples and the diagnosis of EBA; of the 19 serum samples with dermal staining on SSS, only 10 reacted with the EBA antigen. The remaining serum samples were from patients with cicatricial pemphigoid having antibodies to the alpha 3 or beta 3 chains of laminin-5 (n = 5) or patients with BP having antibodies to the 180-kd BP antigen (n = 2). One sample recognized exclusively a 185-kd dermal antigen corresponding to type IV collagen. One more BP serum sample with dermal staining did not recognize any dermal or epidermal antigen. CONCLUSION: In case of immunofluorescent dermal staining, the precise diagnosis should be confirmed by identification of the involved antigen, since it may reveal antibodies to laminin-5 or type XVII or IV collagen, in addition to the EBA antigen. 相似文献
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Three cheetahs (Acinonyx jubatus) had a clinical history of chronic spiral bacteria-associated gastritis and three cheetahs had no clinical history of gastritis. Gastric biopsies were obtained from all six cheetahs prior to treatment for gastritis and 3 wk and 1 yr posttreatment. The cheetahs were treated with tetracycline hydrochloride 500 mg p.o. q.i.d., metronidazole 250 mg p.o. q.i.d., and bismuth subsalicylate 300 mg p.o. q.i.d. Each drug was administered concurrently for 7 days. Following this treatment, each cheetah was maintained on 300 mg bismuth subsalicylate p.o. s.i.d. for 1 yr. The three cheetahs with a history of gastritis were culture positive for Helicobacter acinonyx and remained positive during the entire study. The three cheetahs with no clinical history of gastritis were culture negative for H. acinonyx, but gastric biopsies revealed Gastrospirillum-like bacteria (tentatively named Helicobacter heilmannii) pretreatment. Gastric biopsies were negative for H. heilmannii on subsequent examinations. Although the treatment did not eradicate H. acinonyx, it did provide symptomatic relief from the vomiting, anorexia, and weight loss associated with clinical gastritis. The use of endoscopically guided gastric mucosal biopsies for urease testing and histopathologic examination of Warthin-Starry-stained sections is a sensitive and specific method of diagnosing spiral bacteria-associated gastritis. Treatment of spiral bacteria-associated gastritis in cheetahs should include the rational use of antibiotics (tetracycline or amoxicillin and metronidazole), bismuth compounds, and omeprazole and evaluation of husbandry methods to reduce stress. 相似文献
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TW Mittag A Tormay C Severin T Taniguchi PY Lee RF Wang SM Podos 《Canadian Metallurgical Quarterly》1993,34(3):606-612
PURPOSE: The activity of Al3+, Ga3+, and Be2+ ions in the presence of NaF to directly activate G-proteins was investigated by their potentiative effect on forskolin (FSK)-activated adenylyl cyclase in rabbit ciliary process membranes and their effects on aqueous humor dynamics in vivo. METHODS: Adenylyl cyclase (AC) was determined by radiometric conversion of ATP to cAMP by the particulate fraction of rabbit ciliary processes. Intravitreal injections of sterile solutions of analytical grade salts were made into the center of the vitreous in a volume of 20 microliters. Intraocular pressure, aqueous humor flow, and uveoscleral outflow measurements were made by pneumatonometry, fluorophotometry, and fluorescein-dextran method, respectively. Outflow facility was determined by tonography in the intact eyes and by two-level constant pressure perfusion in cannulated eyes. RESULTS: Both Al3+ (EC50, 40 mumol/l) and Be2+ (EC50, 11 mumol/l) in the presence of 0.5-2 mM NaF activated the stimulatory G-protein Gs. Ga3+ was ineffective and did not antagonize the activation by Al3+. Intravitreal injections of Al3+ (1 mumol/eye) or Be2+ (0.5 or 1 mumol/eye) had no significant intraocular pressure (IOP) effect, nor did 1.5 or 3 mumol/eye of NaF, but when either cation was injected together with NaF, IOP decreased by up to 40% for up to 140 hr. At the time of maximum IOP effect (72 hr) aqueous humor flow determined by fluorophotometry was decreased in BeCl2+ NaF-treated eyes by 40% relative to BeCl2-treated eyes; however, tonographic facility of outflow was unaffected. Uveoscleral flow was also decreased by 38% in BeCl2+ NaF treated eyes. CONCLUSIONS: These findings support the hypothesis that Gs activation of ciliary process adenylyl cyclase decreases aqueous humor formation rate in rabbit eyes, and that activation of G-proteins mediates contraction of ciliary muscles causing a decrease of aqueous humor outflow via the uveoscleral route. The results suggest that G-proteins putatively involved in trabecular facility changes are less sensitive to activation by BeF3- than are other parameters of aqueous humor dynamics. 相似文献
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Using neutral/neutral and neutral/alkaline two-dimensional (2-D) gel techniques, we previously obtained evidence that initiation can occur at any of a large number of sites distributed throughout a broad initiation zone in the dihydrofolate reductase (DHFR) domain of Chinese hamster ovary (CHO) cells. However, other techniques have suggested a much more circumscribed mode of initiation in this locus. This dichotomy has raised the issue whether the patterns of replicating DNA on 2-D gels have been misinterpreted and, in some cases, may represent such noncanonical replication intermediates as broken bubbles or microbubbles. In an accompanying study (R. F. Kalejta and J. L. Hamlin, Mol. Cell. Biol. 16:4915-4922, 1996), we have shown that broken bubbles migrate to unique positions in three different gel systems and therefore are not likely to be confused with classic replication intermediates. Here, we have applied a broken bubble assay developed from that study to an analysis of the amplified DHFR locus in CHO cells. This assay gives information about the number and positions of initiation sites within a fragment. In addition, we have analyzed the DHFR locus by a novel stop-and-go-alkaline gel technique that measures the size of nascent strands at all positions along each arc in a neutral/neutral 2-D gel. Results of these analyses support the view that the 2-D gel patterns previously assigned to classic, intact replication bubbles and single-forked structures indeed correspond to these entities. Furthermore, potential nascent-strand start sites appear to be distributed at very frequent intervals along the template in the intergenic region in the DHFR domain. 相似文献
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BC Odum JS O''Keefe W Lara GT Rodeheaver RF Edlich 《Canadian Metallurgical Quarterly》1998,16(6):875-879
OBJECTIVE: To investigate the lymphocyte subpopulations (T4, T8 and macrophages) and major histocompatibility (MHC) II antigens in patients with superficial bladder cancer before and after intravesical instillations of recombinant interferon-gamma (IFN-gamma). PATIENTS AND METHODS: Four intravesical weekly instillations of either 1.3 mg (20 patients, group A) or 0.7 mg (11 patients, group B) IFN-gamma were administered in 31 evaluable patients (28 men and three women, mean age 68.5 years). The CD4+, CD8+, CD68+ and HLA-DR antigens were detected immunohistochemically in tumours and a marker tumour before and after intravesical instillations. RESULTS: The median number of T4 lymphocytes increased from 15 per high-power field (HPF) to 27.5 in group A (P = 0.0029) and to 45 in group B (P = 0.0117). Macrophages increased from 6 cells/HPF to 15 cells/HPF in group A (P = 0.0029) and from 2 to 8.75 cells/HPF in group B (P = 0.0117). The T8 lymphocyte subpopulation decreased from 4 to 3 cells/HPF (P = 0.0231) in group A and from 5 to 2 cells/HPF (P = 0.0759) in group B. The median percentage of HLA-DR antigens increased from 1.5% to 18% in general, (P < 0.001), from 2.5% to 15% in group A (P = 0.0064) and from 0% to 20% in group B (P = 0.0077). The induction of HLA-DR antigens was statistically significant in those receiving the lower dose (from 0% before instillation to 20% afterward, P = 0.0277), while it was not with the higher dose (from 0% to 5%, P = 0.068). Irrespective of the dose of IFN used. T4 lymphocytes and macrophages increased significantly after treatment in patients in whom the tumour HLA-DR antigens were either up-regulated or remained stable. The median net increase in T4 cells was 17.5 and 30 cells/HPF for groups A and B, respectively (P = 0.0429). CONCLUSION: T4 lymphocytes, macrophages and HLA-DR antigens increased after intravesical IFN-gamma in patients with superficial bladder cancer, but T8 lymphocytes decreased. Irrespective of the drug dose used, patients with either upregulated or stable HLA-DR antigens after treatment showed the same pattern of changes in the lymphocyte subpopulations. The two doses generally had the same effect on the immunological variables assessed but the lower dose was more effective in inducing HLA-DR antigens and in increasing the number of T4 lymphocytes in the tumours. 相似文献
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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