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81.
82.
Giant-cell interstitial Pneumonia (GIP) is a very uncommon respiratory disease. The majority of cases of GIP are caused by exposure to cobalt, tungsten and other hard metals. In this report, we describe GIP in a patient who worked in gas station and dealt in propane gas vessels. He presented with clinical features of chronic interstitial lung disease and underwent an open lung biopsy that showed DIP-like reaction with large numbers of intra-alveolar macrophages and numerous large, multinucleated histiocytes which were admixed with the macrophages. Analysis of lung tissue for hard metals was done. Cobalt was the main component of detected hard metals. Corticosteroid therapy was started and he recovered fully. 相似文献
83.
JM Riesco JA Juanes J Carretero EJ Blanco JM Riesco-Lopez G Vázquez R Vázquez 《Canadian Metallurgical Quarterly》1998,198(6):439-450
To assess the involvement of cellular inhibition and the appearance of apoptosis in regression of the hyperplastic thyroid gland towards normality, an experimental design was used to elicit non-toxic goiter by inducing hyperplastic goiter in rats by treatment with methimazole. We performed a morphological and PCNA immunocytochemical study together with in situ end labelling with bromodeoxyuridine in thyroid glands of rats receiving methimazole in their drinking water over 21 days after which they were allowed a recovery period of 0, 12, 24, 36, 48 and 72 h and 7, 14, 21 and 44 days. Serum T3 and T4 levels were found to be very low in the methimazole-treated animals although they increased after the goitrogenic compound had been withdrawn. Inhibition of cell proliferation and the burst of apoptosis play important roles in the regression of hyperplastic goiter in rats. Cell proliferation, which was strongly stimulated during goiter, fell significantly at 24 h, thereafter decreasing gradually as the recovery period progressed. Isolated cases of thyrocyte necrosis were observed ultrastructurally. Light and transmission electron microscopy revealed the existence of thyroid apoptosis with respect to the development of the study over time. Most apoptotic thyrocytes became detached from the follicular epithelium and later underwent cellular degeneration in the follicular lumen. The remaining apoptotic cells retracted their cytoplasm, lost contact with the follicular lumen and became located at the base of the follicles. The percentage of apoptosis showed that during the first week of thyroid involution apoptosis was already present but with low percentages while maximum values were attained at 21 days of survival. Our results suggest that, in the rat, during the return of thyroid follicular cells to normality after methimazole-induced hyperplastic goiter a balance arises between proliferation and cell death and that this balance is due to the inhibition of cellular proliferation and, secondarily, to the appearance of apoptosis, which becomes particularly evident towards the end of the first week after withdrawing the goitrogenic agent. 相似文献
84.
DJ Kereiakes AM Lincoff DP Miller JE Tcheng CF Cabot KM Anderson HF Weisman RM Califf EJ Topol 《Canadian Metallurgical Quarterly》1998,97(9):857-864
BACKGROUND: Recent studies indicate that eradication of Helicobacter pylori might prevent peptic ulcer formation in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs). On the other hand, gastric adaptation after repeated exposures to aspirin (ASA) is well documented but the influence of H. pylori on this process remains to be elucidated. AIM: To compare gastric damage and adaptation following repeated exposures to ASA in a group of patients with H. pylori infection, before and after eradication of the bacterium, and in H. pylori-negative controls. METHODS: Eight healthy volunteers without H. pylori infection and eight patients with duodenal ulcer (DU) history and H. pylori infection before and after H. pylori eradication were given ASA 2 g/day for a period of 14 days. Mucosal damage was evaluated by endoscopy and histology of biopsy samples. Gastric microbleeding, DNA synthesis in the gastric mucosa and mucosal expression, as well as luminal content of transforming growth factor-alpha (TGFalpha) were determined on days 0, 3, 7 and 14 of the ASA course. RESULTS: In all patients aspirin-induced gastric damage reached a maximum on day 3. In H. pylori-positive patients, this damage was maintained at a similar level up to day 14, whereas in H. pylori-negative controls and H. pylori-eradicated patients this damage significantly lessened on day 14 and was accompanied by elevated DNA synthesis as well as increased mucosal expression and luminal release of TGFalpha. 相似文献
85.
CJ Quaife EJ Kelly BA Masters RL Brinster RD Palmiter 《Canadian Metallurgical Quarterly》1998,148(1):148-157
Mice express four distinct metallothioneins (MTs) that have similar metal-binding properties. MT-I and MT-II are expressed coordinately in most organs, whereas MT-III is expressed predominantly in a subset of neurons and MT-IV is expressed in certain stratified epithelia. The restricted expression of MT-III suggests that it may severe a specialized function. To test this hypothesis, transgenic mice were generated that express MT-III in the wider expression domain of MT-I. Similar transgenic lines expressing extra MT-I under the same regulation were generated as controls for the effect of over-expression of MT. Transgenic mice that express MT-III ectopically frequently die at 2-3 months of age. The pancreata of moribund mice were abnormally small and histological examination, at various ages, revealed a progressive degeneration of the acinar cells. At early stages multifocal acinar cell eosinophilia and swollen nuclei were seen and this pathology progressed to multifocal acinar cell necrosis and fibrosis. The terminal stages were characterized by a loss of the acinar compartment, leaving the islets embedded in a fibrotic remnant. Other organs of these mice were grossly and histologically normal. All organs examined from mice expressing excess MT-I were unremarkable even though expression of either MT-I or MT-III transgenes resulted in similar accumulations of zinc and copper in the pancreata. This study indicates that pancreatic acinar cells are unusually sensitive to chronic expression of MT-III. The mechanism by which MT-III disrupts pancreatic function is unclear, but the results provide further evidence that MT isoforms exhibit distinct properties and probably serve distinct biological functions. 相似文献
86.
EJ Shillitoe S Noonan CC Hinkle FC Marini RM Kellman 《Canadian Metallurgical Quarterly》1998,5(3):176-182
Considerable basic research, mostly in the past 20 years, has elicited greatly increased knowledge concerning the structure and function of cell adhesion molecules. Scores of individual adhesion molecules have been identified and categorized as to major structural features, ligands recognized, and pattern of expression. Recent attention has been focused on the interaction of cell adhesion molecules with intracellular components, and the role of cell adhesion molecules in mediating cell signal transduction. Ongoing efforts to develop specific pharmacological agonists and antagonists for adhesion molecules holds great promise in clinical medicine. Abciximab (Reopro), a monoclonal antibody inhibitor of the platelet integrin alpha IIb beta 3, is currently approved and available to improve vessel patency in patients undergoing angioplasty. Similar approaches to develop adhesion-based therapies to block angiogenesis, tumor progression, and/or metastasis are under development and hold promise for patients with cancer. 相似文献
87.
Quantitative buffy coat (QBC) analysis has been reported to have a high degree of methodical sensitivity in the detection of human filariasis. This study was conducted to evaluate its usefulness in the diagnosis of filariasis using a Dirofilaria immitis/dog model. By necropsy of 244 stray dogs, 40.6% of the animals were found to harbor 1-58 worms of D. immitis (mean 6.5 +/- 8.4 worms/infected dog). The QBC analysis and thick blood smear (TBS) method detected microfilaremia in 31.6% and 21.3% of these dogs, respectively. The results of these two methods were highly correlated with the presence of bisexual worms in the dogs. The QBC analysis was more sensitive (55% versus 39%) and efficient (79% versus 72%) than the conventional TBS method. However, accurate speciation of the microfilariae was impossible using the QBC analysis. Although this technique is more sensitive, simpler, and less time-consuming and does not require as much skill or experience in comparison with the conventional TBS method, the failure in speciation of the parasites may limit its usefulness. 相似文献
88.
GA Christoforidis BA Mehta JL Landi EJ Czarnecki RA Piaskowski 《Canadian Metallurgical Quarterly》1998,40(10):636-643
Spontaneous intracranial hypotension is an unusual syndrome of postural headache and low cerebrospinal fluid pressure without an established cause. We present four cases, analyze those previously reported in the literature, examine the MRI, CT, angiographic and cisternographic finding and discuss the clinical picture, proposed pathophysiologic mechanisms and potential treatment. 相似文献
89.
90.
Protein shedding, or the proteolytic cleavage of a protein from the surface of a cell, is emerging as an important mechanism in the regulation of cellular activity but it is poorly understood. Growing evidence suggesting that protein shedding and protein function are closely linked may lead to new strategies for the treatment of a wide range of diseases. 相似文献