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151.
Diclofenac antiserum was previously developed and used to detect protein adducts of metabolites of dichlofenac in livers of mice and rats. In this study, the antibody has been used to facilitate the purification of a major 51 kDa microsomal adduct of diclofenac from the liver microsomes of male rats that were treated with diclofenac. The adduct was identified as male-specific cytochrome P4502C11 based on its N-terminal amino acid sequence, reaction with a cytochrome P4502C11 antibody, and by its absence from liver microsomes of diclofenac-treated female rats. When diclofenac was incubated with liver microsomes of control rats in the presence of NADPH, only the 51 kDa adduct was produced. The formation of the adduct was inhibited by a cytochrome P4502C11 monoclonal antibody, but not by reduced glutathione or N-alpha-acetyl-L-lysine. No adduct was detected when diclofenac was incubated with liver microsomes from female rats. Moreover, adduct formation in vivo appeared to lead to a 72% decrease in the activity of cytochrome P4502C11. The results indicate that cytochrome P4502C11 metabolizes diclofenac into a highly reactive product that covalently binds to this enzyme before it can diffuse away and react with other proteins. 相似文献
152.
CE French AM Hailes DA Rathbone MT Long DL Willey NC Bruce 《Canadian Metallurgical Quarterly》1995,13(7):674-676
Semisynthetic derivatives of morphine and related alkaloids are in widespread clinical use. Due to the complexity of these molecules, however, chemical transformations are difficult to achieve in high yields. We recently identified the powerful analgesic hydromorphone as an intermediate in the metabolism of morphine by Pseudomonas putida M10. Here we describe the construction of recombinant strains of Escherichia coli that express morphine dehydrogenase and morphinone reductase. These strains are capable of efficiently transforming the naturally occurring alkaloids morphine and codeine to hydromorphone and the antitussive hydrocodone, respectively. Our results demonstrate the potential for recombinant DNA technology to provide biological routes for the synthesis of known and novel semisynthetic opiate drugs. 相似文献
153.
LJ Seidman JM Goldstein JM Goodman D Koren WM Turner SV Faraone MT Tsuang 《Canadian Metallurgical Quarterly》1997,42(2):104-115
We investigated the hypothesis that different prefrontal brain systems (i.e., dorsal vs. ventral) and sex contribute differentially to cognitive deficit in schizophrenia. Performance was assessed among clinically stable, chronic schizophrenic outpatients and matched normal control subjects on olfactory identification [on the University of Pennsylvania Smell Identification Test (UPSIT)] and on executive functions [using the Wisconsin Card Sorting Test (WCST)]. Patients were impaired on both tests compared to controls, and male schizophrenics were impaired on the WCST compared to female schizophrenics. The pattern of results suggests that gender differences on the UPSIT are mildly accentuated in schizophrenia. The data support our previous study indicating that UPSIT performance is largely independent of the executive or attentional deficits typically associated with schizophrenia, with the exception of verbal ability. Further research with larger samples is required to test the hypothesis that there is a severely impaired subgroup of male patients with diffuse prefrontal dysfunctions. 相似文献
154.
Heterotopic brain tissue, except in the head and neck region, is exceedingly rare. Mature neural tissue unexpectedly found in the subcutaneous tissues of the back of a toddler lacked an attachment to the central nervous system (CNS), and appeared to be unorganized glial tissue on pathologic evaluation. Appropriate clinical management of such lesions includes a suspicion of subcutaneous lesions near the CNS and evaluation to eliminate the presence of communication with the CNS, followed by surgical excision. 相似文献
155.
IL-4 activates resting B cells and, in conjunction with cosignals such as anti-IgM (anti-mu) Ab or CD40 ligand, modulates progression of B cells through the cell cycle, leading to proliferation. In this study, we show that the mitogenic combination of IL-4 and anti-mu Ab triggered induction of cyclin D3 and up-regulated cyclin-dependent kinase (cdk) 6 expression, whereas such regulation was not observed in B cells activated by IL-4 or anti-mu Ab alone. Furthermore, cyclin D3 immunoprecipitated fron as associated with cdk6, and the cyclin D3/cdk6 complex was able to phosphorylate recombinant retinoblastoma protein in vitro. In addition, B cells activated with either IL-4 or 1L-13 alone expressed a higher amount of p27kip1 (p27) cdk inhibitor than nonstimulated cells. In contrast, p27 expression was decreased when cells were activated with mitogenic combinations of IL-4 and anti-mu Ab or anti-CD40 mAb. We also observed that the IL-4-mediated inhibition of the proliferation of anti-mu/IL-2- or anti-mu/phorbol 12,13-dibutyrate-activated human leukemic B cells was associated with the maintenance of large amounts of p27 in these cells. These data suggest that IL-4 controls B cell proliferation by action during at least two steps of the regulation of the cell cycle, cyclin D3/cdk6 complex regulation and p27 inhibitor expression. 相似文献
156.
S De Angeli C Favretti S Buoro A Fandella G Anselmo MT Conconi PP Parnigotto 《Canadian Metallurgical Quarterly》1997,179(3):255-264
Investigation of Prussak's space and its relationship to adjacent spaces is important in elucidating the cause of retraction pocket and cholesteatoma formation in this space. This study was designed to quantitatively characterize the chronological development of Prussak's space and its relationship to adjacent spaces in temporal bones. One-hundred and forty-nine human temporal bone slides (115 normal, 28 with otitis media with effusion, three with retraction pockets and three with attic type cholesteatoma) including specimens ranging from fetal to adult bones were studied. Prussak's space was formed and sufficient aeration routes established by 4 years of age in normal temporal bones. In temporal bones with otitis media with effusion, however, the growth of Prussak's space was suppressed and few routes for aeration established until 10 years of age. In normal temporal bones, Prussak's space developed with aeration routes sufficient to avert the negative pressure which can result in retraction pocket formation in the pars flaccida of the tympanic membrane. 相似文献
157.
JB Bjorner S Kreiner JE Ware MT Damsgaard P Bech 《Canadian Metallurgical Quarterly》1998,51(11):1189-1202
Statistical analyses of Differential Item Functioning (DIF) can be used for rigorous translation evaluations. DIF techniques test whether each item functions in the same way, irrespective of the country, language, or culture of the respondents. For a given level of health, the score on any item should be independent of nationality. This requirement can be tested through contingency-table methods, which are efficient for analyzing all types of items. We investigated DIF in the Danish translation of the SF-36 Health Survey, using two general population samples (USA, n = 1,506; Denmark, n = 3,950). DIF was identified for 12 out of 35 items. These results agreed with independent ratings of translation quality, but the statistical techniques were more sensitive. When included in scales, the items exhibiting DIF had only a little impact on conclusions about cross-national differences in health in the general population. However, if used as single items, the DIF items could seriously bias results from cross-national comparisons. Also, the DIF items might have larger impact on cross-national comparison of groups with poorer health status. We conclude that analysis of DIF is useful for evaluating questionnaire translations. 相似文献
158.
F Martín J Pintor JM Rovira C Ripoll MT Miras-Portugal B Soria 《Canadian Metallurgical Quarterly》1998,12(14):1499-1506
In pancreatic beta-cells, stimulatory glucose concentrations increase cytosolic diadenosine polyphosphates ([ApnA]i) to concentrations sufficient to block ATP-sensitive K+ (KATP) channels. High-performance liquid chromatography and patch clamp techniques were used to study the metabolic pathways by which pancreatic beta-cells synthesize ApnA and the mechanism through which ApnA inhibit KATP channels. ApnA show a glucose- and time-dependent cytosolic concentration increase parallel, though 30- to 50-fold higher, to changes observed in adenine nucleotides. Other fuel secretagogues, leucine and 2-ketoisocaproate, raise [ApnA]i as efficiently as 22 mM glucose. Blockade of glycolysis or Krebs cycle decreases glucose-induced [ApnA]i. No significant increase in cytosolic ApnA concentrations is induced by nonnutrient secretagogues or nonmetabolizable nutrient secretagogues. Inorganic pyrophosphatase inhibition with sodium fluoride blocks 22 mM glucose-induced [ApnA]i increase. ApnA inhibition of KATP channel resembles that of ATP in efficacy, but shows clear functional differences. Unlike ATP, Ap4A does not restore channel activity after rundown. Furthermore, these compounds do not compete with each other for the same site. These features suggest a prominent role for Ap4A in beta-cell function, comparable to ATP. We conclude that nutrient metabolism through pyrophosphatase activation is necessary to induce ApnA synthesis, which in turn constitutes a new, ATP-independent, metabolic regulator of KATP channel activity. 相似文献
159.
160.
MT Certi Mazza L De Cicco G De Rosa R De Rosa R Caramazza 《Canadian Metallurgical Quarterly》1996,72(3-4):79-86
The activities of cell-associated IL-1 (IL-1 alpha) and extracellular IL-1 (IL-1 beta) in alveolar macrophages (AM) from rats with bleomycin-induced pulmonary fibrolosis were measured to determine their role in fibroblast growth. AM were obtained on Days 1, 3, 6, 9 and 12 after a intratracheal injection of bleomycin, and the IL-1 activity and fibroblast growth-stimulating activity in fixed AM and AM supernatants were measured. Higher cell-associated IL-1 activity was detected in AM from bleomycin-treated rats than in those of control on Day 1 through 9. But extracellular IL-1 activity in the supernatant of AM from bleomycin-treated rats significantly higher only on Day 1. Expression of IL-1 alpha mRNA in AM from bleomycin-treated rats was significantly higher than that in AM of control, but there was no significant difference in the mRNA levels of IL-1 beta in AM of these two groups. Fixed AM from bleomycin-treated rats caused growth-inhibition of fibroblasts in a density-dependent manner. The inhibitory activity was decreased by pretreatment of fixed AM with anti IL-1 alpha antibody, but not anti IL-1 beta antibody. These results suggest that cell-associated IL-1 (IL-1 alpha) is produced continuously in AM from rats with bleomycin-induced pulmonary fibrosis and may be important in regulation of this disorder by inhibiting fibroblast growth. 相似文献