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41.
The report shows that Alzheimer's disease (AD) brain creatine kinase (CK) is modified such that the nucleotide binding site of CK is blocked and that abnormal partitioning of CK between the soluble and pellet fractions occurs. First, CK activity was 86% decreased in AD brain homogenates in comparison to age-matched controls. Secondly, over a 23.5 fold greater 32P photoincorporation of [alpha 32P]8N3ATP was observed into CK of control vs. AD samples. Also, a 7.4-fold increase of enzyme induced 32P incorporation was observed in controls vs. AD samples by incubation with [gamma 32P]ATP. Thirdly, Western blot analysis showed that CK copy numbers in the AD homogenate were decreased by less than 14% in comparison to controls. However, analysis showed that control supernatant and pellet fractions contained 10.3 and 0.4 times the CK copy number found in the corresponding AD fractions. 32P incorporation by both photolabeling and enzyme catalyzed incorporation of radiolabel followed CK activity and not CK copy number. Further, [alpha 32P]ADP and [gamma 32P]ATP incorporated 32P into control brain and purified brain CK equally well, indicating that a mechanism different from gamma-phosphoryl transfer is involved in the enzymatic incorporation of radiolabel. Also, the level of abnormal partitioning of CK into AD brain pellet correlated with the decreased [32P]8N3GTP photolabeling and abnormal partitioning of beta-tubulin, a protein known to be aberrantly modified in the AD brain. This indicates that a common chemistry is affecting both CK and tubulin in AD. 相似文献
42.
EH Luque MM Mu?oz de Toro JG Ramos HA Rodriguez OD Sherwood 《Canadian Metallurgical Quarterly》1998,59(4):795-800
The modified fluorescence method was used to determine the accumulation of norfloxacin by Mycobacterium aurum A+ and Mycobacterium smegmatis mc(2)155. By using an exogenous norfloxacin concentration of 10 microg/ml, a steady-state concentration (SSC) of 160 to 180 ng of norfloxacin/mg of cells was obtained for M. aurum, and an SSC of 120 to 140 ng of norfloxacin/mg of cells obtained for M. smegmatis. For both species of mycobacteria, the SSC was achieved within 5 min. The silicon oil method was investigated and gave higher SSCs than the modified fluorescence method. Further studies on the mechanism of norfloxacin accumulation by M. aurum were performed. An increase in the pH of the wash buffer from 7.0 to 9.0 did not significantly affect the final SSC obtained. Accumulation was nonsaturated over a norfloxacin concentration range of 0 to 100 microg/ml, and the proton motive force inhibitor 2,4-dinitrophenol (1 and 2 mM), whether it was added before or after norfloxacin was added, had no effect on the final SSC obtained. 2,4-Dinitrophenol also had no effect on norfloxacin accumulation by M. smegmatis. Furthermore, norfloxacin accumulation by M. aurum was unaffected by the presence of either Tween 80 or subinhibitory concentrations of ethambutol in the growth medium. Therefore, it is proposed that norfloxacin accumulation by mycobacteria occurs by simple, energy-independent diffusion. 相似文献
43.
EH Hopman L Rozendaal RH Verheijen P Kenemans TJ Helmerhorst 《Canadian Metallurgical Quarterly》1998,77(2):229-234
PURPOSE: The objective of this study was to correlate the findings of sarcoidosis on high resolution CT (HRCT) with indexes of disease activity as measured with 67Ga scan, bronchoalveolar lavage (BAL), and serum angiotensin-converting enzyme (SACE) assay. METHOD: Twenty-nine patients with proven sarcoidosis underwent HRCT scan, 67Ga scan, BAL, and SACE assay within a 1 month period. The extent of parenchymal involvement by nodules, consolidation, ground-glass attenuation, and linear opacities was quantified to the nearest 10% of surface area affected on the CT examination. Whole-lung gallium uptake was quantified and the percentage of BAL-recovered lymphocytes (BAL-%LC) and SACE levels obtained by chart review. CT scores of disease extent were correlated with measured indexes of activity using the Spearman rank correlation coefficient. RESULTS: The mean extent of nodules, consolidation, ground-glass attenuation, and linear opacities on HRCT images was 15.1 +/- 16.6, 1.6 +/- 4.0, 17.5 +/- 25.4, and 7.6 +/- 9.6%, respectively. The extent of nodules and consolidation correlated with the intensity of lung gallium uptake (r = 0.46, p < 0.02), BAL-%LC (r = 0.50, p < 0.01), and SACE levels (r = 0.38, p < 0.05). No significant correlation was found between extent of ground-glass attenuation or linear opacities with any indexes of disease activity. CONCLUSION: On HRCT scan, nodules and consolidation in sarcoidosis reflect disease activity as measured by 67Ga scan, BAL, and SACE assay. 相似文献
44.
J Yu SL Wolda AL Frazier VA Florio TJ Martins PB Snyder EA Harris KN McCaw CA Farrell B Steiner JK Bentley JA Beavo K Ferguson R Gelinas 《Canadian Metallurgical Quarterly》1997,9(7):519-529
A cDNA encoding a calmodulin-stimulated 3',5'-cyclic nucleotide phosphodiesterase (PDE) was isolated from a human brain cDNA library. The cDNA, designated HSPDE1B1, encoded a protein of 536 amino acids that shared 96% sequence identity with the bovine "63 kDa" calmodulin-stimulated PDE. The recombinant protein had cyclic nucleotide phosphodiesterase activity that was stimulated approximately 2-fold by Ca2+/calmodulin and preferred cGMP as substrate. In addition, the enzymatic activity of HSPDE1B1 was inhibited by phosphodiesterase inhibitors with potencies similar to that displayed toward the bovine PDE1 enzymes: IBMX approximately equal to 8-methoxymethyl-IBMX > vinpocetine approximately equal to zaprinast > cilostamide > rolipram. HSPDE1B1 mRNA was found predominantly in the brain. Lower mRNA levels were found in heart and skeletal muscle. In situ hybridisation of brain revealed expression of HSPDE1B1 predominately in neuronal cells of the cerebellum, hippocampus and caudate. The HSPDE1B1 gene was mapped to human chromosome 12. A partial genomic sequence of HSPDE1B1 was isolated and shown to contain two splice junctions that are conserved in the rat PDE4 and the Drosophila dunce genes. 相似文献
45.
The purpose of the study was to give a histological picture of the different skin regions of the mammary gland in mares. Special emphasis on the dark coating in the sulcus intermammarius was given. As a result, the dark pigmented udder skin can be subdivided into the skin of the Corpus mammae, the sulcus intermammarius and the teat skin. In the sulcus intermammarius the whole epidermis was considerably thicker than usual, especially the stratum corneum (up to 70 layers of cornified layers) and the stratum spinosum. In general, the squamous keratinocytes were unusually large. The histological preparations of the coating revealed a stratum corneum instead of a supposed secretion of the sebaceous glands. The dermal papillae ended immediately below the stratum corneum. 相似文献
46.
SP Kachur ME Reller AM Barber LM Barat EH Koumans ME Parise J Roberts TK Ruebush JR Zucker 《Canadian Metallurgical Quarterly》1997,46(5):1-18
PROBLEM/CONDITION: Malaria is caused by infection with one of four species of Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, and P. malariae ), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malarial infections in the United States occur in persons who have traveled to areas (i.e., other countries) in which disease transmission is ongoing. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to adapt prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of symptoms during 1994. DESCRIPTION OF SYSTEM: Malaria cases confirmed by blood smear are reported to local and/or state health departments by health-care providers and/or laboratories. Case investigations are conducted by local and/or state health departments, and the reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), which was the source of data for this report. Numbers of cases reported through NMSS may differ from those reported through other passive surveillance systems because of differences in the collection and transmission of data. RESULTS: CDC received reports of 1,014 cases of malaria with onset of symptoms during 1994 among persons in the United States or one of its territories. This number represented a 20% decrease from the 1,275 cases reported for 1993. P. vivax, P. falciparum, P. malariae, and P. ovale accounted for 44%, 44%, 4%, and 3% of cases, respectively. More than one species was present in five persons (<1% of the total number of patients). The infecting species was not determined in 50 (5%) cases. The number of reported malaria cases in U.S. military personnel decreased by 86% (i.e., from 278 cases in 1993 to 38 cases in 1994). Of the U.S. civilians who acquired malaria during travel to foreign countries, 18% had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Five persons became infected while in the United States; the infection was transmitted to two of these persons through transfusion of infected blood products. The remaining three cases, which occurred in Houston, Texas, were probably locally acquired mosquitoborne infections. Four deaths were attributed to malaria. INTERPRETATION: The 20% decrease in the number of malaria cases from 1993 to 1994 resulted primarily from an 86% decrease in cases among U.S. military personnel after withdrawal from Somalia. Because most malaria cases acquired in Somalia during 1993 resulted from infection with P. vivax, there was a proportionately greater decrease during 1994 in the number of cases caused by P. vivax relative to those caused by P. falciparum. ACTIONS TAKEN: Additional information was obtained concerning the four fatal cases and the five cases acquired in the United States. Malaria prevention guidelines were updated and distributed to health-care providers. Persons traveling to a geographic area in which malaria is endemic should take the recommended chemoprophylactic regimen and should use protective measures to prevent mosquito bites. Persons who have a fever or influenza-like illness after returning from a malarious area should seek medical care; medical evaluation should include a blood smear examination for malaria. Malarial infections can be fatal if not promptly diagnosed and treated. Recommendations concerning prevention and treatment of malaria can be obtained from CDC. 相似文献
47.
OBJECTIVE: To determine the frequency of adverse reactions, particularly the occurrence of apnea, among preterm infants after immunization with diphtheria and tetanus toxoids and whole cell pertussis vaccine adsorbed (DTP) and Haemophilus influenzae type b conjugate (HibC) vaccine in the neonatal intensive care unit. STUDY DESIGN: After the occurrence of apnea in two preterm infants following immunization with DTP and HibC, a prospective surveillance of 97 preterm infants younger than 37 weeks of gestation who were immunized with DTP (94 also received HibC at the same time) in the neonatal intensive care unit was performed to assess the frequency of adverse reactions and in particular, the occurrence of apnea. For each infant, data were recorded for a 3-day period before and after receipt of the immunization. RESULTS: The majority of preterm infants tolerated immunizations with DTP and HibC without ill effects. However, 12 (12%) infants experienced a recurrence of apnea, and 11 (11%) had at least a 50% increase in the number of apneic and bradycardic episodes in the 72 hours after immunization. This occurred primarily among smaller preterm infants who were immunized at a lower weight (p = 0.01), had experienced more severe apnea of prematurity (p = 0.01), and had chronic lung disease (p = 0.03). CONCLUSION: The temporal association observed between immunization of preterm infants and a transient increase or recurrence of apnea after vaccination merits further study. Cardiorespiratory monitoring of these infants after immunization may be advisable. 相似文献
48.
von Hecker U P Zarnoth JA Sniezek JF Dovidio SL Gaertner A Validzic K Matoka B Johnson S Frazier TR Mitchell L Thompson E Peterson R Cronk 《Canadian Metallurgical Quarterly》1997,33(4):367-400
Starting from recent approaches in mental model research, it is argued that (1) logical inference rules are used in order to construct mental cliques from learned sentiment relations, and (2) social context cues (operationalized as primes) play a crucial role in activating such rules. Transitivity and antitransitivity are taken as examples, and are shown as core constituents of such models. In a first experiment, priming was achieved by announcing the sorting of fictitious persons in either two or three cliques. Thirty-one subjects studied eight sets of sentiment relations among these persons that either did or did not satisfy their primed clique expectations. They showed longer study times and more requests for additional information in the case of inconsistent fits between prime and set. Their sorting solutions also showed clear priming effects. A second experiment (n = 30) showed that when undergoing a recognition test after seeing the relation sets, subjects tended to confuse model-consistent distractors with information they had actually seen. In a third experiment (n = 30) the results from Experiment 1 were replicated using more realistic learning materials. 相似文献
49.
C Ward GI Snell B Orsida L Zheng TJ Williams EH Walters 《Canadian Metallurgical Quarterly》1997,10(12):2876-2880
Lung transplantation is now an established therapeutic intervention for end-stage cardiopulmonary disease in humans. Chronic rejection, in the form of bronchiolitis obliterans syndrome (BOS), remains the commonest cause of morbidity and mortality in those surviving more than 3 months. The pathology of BOS involves airway changes. We have evaluated the potential for endobronchial biopsies (EBB) to complement existing sampling methods used in allograft monitoring and have compared the results of EBB findings with those of bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) in 18 clinically stable patients. We found that all the EBB had inflammatory cells present but that only five TBB specimens had evidence of inflammation, with airway material being present in 78% of the TBB. Paired BAL and EBB yielded different results, with no correlations between total macrophages, lymphocytes, CD4+ cells or CD8+ cells. We conclude that endobronchial biopsies are potentially useful as an additional sample for the monitoring of inflammation in lung allografts, since they yield different, and potentially complimentary, information to bronchoalveolar lavage and transbronchial biopsy. 相似文献
50.
OBJECTIVE: To compare the presentation and outcome of depression between young and elderly patients. DESIGN: The clinical presentation, treatment and outcome of 47 young patients (21 to 64 years) were compared with 58 elderly (65 years and older) patients admitted to a general hospital psychiatric ward for the treatment of depressive disorders (based on ICD-10). SUBJECTS: There was no significant difference between the sexes in each age group. The majority of the elderly were either widowed (36%) or married (53%) while 45% of the young were single and 51% married. Seventy per cent of the elderly had retired while 64% of the young were in full-time employment. Most patients lived with their families (87% young and 96% elderly). All but one elderly suffered at least one physical disorder with two-thirds having two or more physical disorders; this contrasts greatly to young patients who were physically healthier (p < 0.001). RESULTS: In clinical presentation and symptomatology, the young patients had significantly more suicide ideation (p < 0.003) and psychomotor retardation (p < 0.001) but there was no difference in suicidal attempt, delusion, hallucination or agitation. More young patients (36%) had a past psychiatric illness (often depressive disorders) than elderly patients (8%) (p < 0.001), more elderly patients (88%) were treated with antidepressants than the young patients (62%) (p < 0.002). At one year follow-up, more elderly patients (46%) recovered compared with the young patients (23%) (p < 0.05). CONCLUSION: There were some differences in the symptomatology of depression between young and elderly patients, but the prognosis was better for elderly patients. 相似文献