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991.
Previous gene expression profiling studies in Drosophila have provided clues for understanding the aging process at the gene expression level. For a detailed understanding, studies of specific regions of the body are necessary. We therefore employed microarray analysis to examine gene expression changes in the Drosophila head during aging. Six hundred and eighty-four of the 5405 genes present in the microarray showed significant age-dependent changes as determined by significance analysis of microarray (SAM) (q < 0.05). The biological significance of the changes was analyzed using the gene annotations provided by the Gene Ontology Consortium. Major changes involved genes affecting energy metabolism (proton transport, energy pathways, oxidative phosphorylation) and neuronal function, especially responses to light. Genes involved in protein catabolism and several other metabolic processes also showed age-dependent changes. Most of the changes were reductions in gene expression and occurred before day 13 of adult life. After day 13, the age-dependent gene expression changes were relatively smaller than earlier life. Interestingly, the two biological processes of major gene expression changes are related to the two known environmental changes that increase life span in Drosophila: caloric restriction and light reduction. Our findings suggest that light signaling and energy metabolism may be important biological processes affected by aging and be interesting targets for the further investigation related to the longevity in Drosophila.  相似文献   
992.
The formalin test is a model of injury-produced inflammatory pain. Anesthetics, in clinically relevant concentrations, affect neutrophils and immune suppression. This study was to determine whether halothane reliably inhibits inflammatory reaction and formalin induced pain behavior or does not. Rats were exposed to 100% oxygen (control) or halothane, respectively for 30 min and then 24 hr later five percent formalin test was assessed. The base values of the paw's diameter were obtained earlier, and then formalin induced edema was assessed by measuring diameters of the injected paws at 5 min, 1 hr, 4 hr and 24 hr after the injection. Nociceptive behavior was quantified by counting the number of times with the paw flinched at 5 min intervals for 60 min. The diameters of edema in the halothane group lessened more than those in the oxygen group at 1 and 24 hr in each following of the injection (p<0.05). The rats pre-administered with oxygen or halothane were similar appearances in nociceptive behaviors. It suggests that halothane anesthesia might inhibit slightly the inflammatory reaction with the formalin-induced edema but might not inhibit the formalin-induced pain behavior in the event of pre-administration halothane 24 hr earlier before the formalin test of rat.  相似文献   
993.
The copper-deficient rat-trypanosome system was used to study copper deficiency in Sprague Dawley rats infected with Trypanosoma lewisi. Throughout the observational period, animals on the deficient diet had lower plasma and liver copper concentrations compared with complete and pair-fed animals. In all dietary groups, the food intake and body weight changes of rats inoculated with T lewisi showed significant increases over the noninoculated controls. The rate of these indices were significantly less in the copper-deficient animals compared with the animals fed complete diets. Copper-deficient and pair-fed control rats showed greater numbers of parasites than controls throughout the infection. The duration of the trypanosomal infection was longer in copper-deficient rats compared with other groups. In all of the dietary groups, severe depression in the primary and secondary antibody responses (IgM and IgG) to in vivo immunization with sheep erythrocytes was observed in infected animals over noninfected controls. The results of the present study indicate that during copper deficiency, there are significant changes in food consumption and body weight and enhanced susceptibility to infection as measured by an increased parasitemia and depression in the antibody responses.  相似文献   
994.
The effect of in ovo administration of ovine growth hormone (oGH) on growth and adipose tissue development of chickens was investigated. Unlike mammalian species, exogenous growth hormone has not been previously shown to increase growth of aves. In trial 1, fertilized eggs were injected with vehicle (.03 M NaHCO3 in .15 M NaCl, pH 8.3), 0.25, 2.5, 25 or 250 micrograms oGH on day 11 of embryogenesis. In trial 2, fertile eggs were injected with vehicle or 250 micrograms oGH. In contrast to previous studies in which GH was administered to growing birds, oGH injected in ovo in the present study increased body weights, skeletal growth and feed efficiencies of male broilers. Growth rate was not altered in females. Adipose cellularity data from both trials indicated that in ovo oGH also altered adipose tissue development of broilers. Seven-week-old male and female broilers treated with oGH during embryogenesis exhibited larger adipocytes with correspondingly less cell per gram of tissue. Additionally, adipocytes from oGH-treated broilers exhibited decreased sensitivity to glucagon, cholera toxin or theophylline-induced lipolysis responsiveness to dcAMP in ovo. Cholera toxin plus theophylline improved the lipolytic response of oGH-treated birds; thus, in broilers injected with oGH cAMP-mediated lipase activation may be reduced by a mechanism of increased phosphodiesterase activity. The results of this study indicate that growth and tissue development of chickens have been altered by mammalian GH in ovo.  相似文献   
995.
Human isolates of the intestinal pathogen Campylobacter jejuni have been shown to colonize mucus on the outer surface and deep within the intestinal crypts of gnotobiotic or germfree mice. The cecal crypts are preferentially colonized. A model of mucus colonization by C. jejuni in the mouse cecum has been developed, using antibiotic- and magnesium sulfate-treated specific-pathogen-free animals. These spiral-shaped bacteria colonize the mucus in a similar manner to the normal spiral-shaped microbiota. No evidence of adhesion to the intestinal surface was found with a wide variety of microscopic techniques. The campylobacters were seen to be highly motile in living preparations of gut tissue and rapidly tracked along intestinal mucus. Just as many of the normal spiral-shaped bacteria of intestinal surfaces can achieve close association with the epithelium through mucus association and do not adhere to the surface, C. jejuni colonizes the intestinal mucosa via mucus colonization. Thus, a major determinant of pathogenicity in intestinal infection with C. jejuni is proposed to be an ability to colonize intestinal mucus. The possession of specific adhesins is unlikely to be a significant determinant of pathogenicity. Better understanding of the mechanism of mucus association and the properties of the bacterium that are responsible will provide a basis for the rational selection of preventative measures. The model of mucus association in adult antibiotic-treated mice provides an opportunity for colonization studies with variant organisms and immunization studies.  相似文献   
996.
IgE antibodies were produced in mice and rats by immunization with ragweed pollen extract (RAG) or dinitrophenylated ovalbumin (DNP3-OA). Treatment of these animals with tolerogenic conjugates of (i) the antigen (RAG or OA) with monomethoxypolyethylene glycol (mPEG), or (ii) DNP with polyvinyl alcohol (DNP-PVA) resulted, within 7-14 days, in a fall in circulating IgE antibodies and in mast cell sensitivity, as assessed by the radioallergosorbent test (RAST) and in the in vitro antigen-induced histamine release (HR) test, respectively. The reduction in responsiveness was more marked in mice than rats; 10 days after a booster immunization, the IgE antibody titres in the RAG-mPEG-treated group of mice were approximately 10-fold lower than in the saline-treated group, with a 100-fold difference in cell sensitivity. DNP-PVA treatment of mice produced a more than 10-fold reduction in IgE anti-DNP titres with a substantial reduction in histamine release.  相似文献   
997.
PurposeDissection after plain balloon angioplasty is required to achieve adequate luminal area; however, it is associated with a high risk of vascular events. This study aimed to examine the relationship between non-flow limiting coronary dissections and subsequent lumen loss and long-term clinical outcomes following successful drug-coated balloon (DCB) treatment of de novo coronary lesions.Materials and MethodsA total of 227 patients with good distal flow (Thrombolysis in Myocardial Infarction flow grade 3) following DCB treatment were retrospectively enrolled and stratified according to the presence or absence of a non-flow limiting dissection. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization, and target vessel thrombosis).ResultsThe cohort consisted of 95 patients with and 132 patients without a dissection. There were no between-group differences in LLL (90.8%) returning for angiography at 6 months (0.05±0.19 mm in non-dissection and 0.05±0.30 mm in dissection group, p=0.886) or in TVF (6.8% in non-dissection and 8.4% in dissection group, p=0.799) at a median follow-up of 3.4 years. In a multivariate analysis, the presence of dissection and its severity were not associated with LLL or TVF. Almost dissections (93.9%) were completely healed, and there was no newly developed dissection at 6-month angiography.ConclusionThe presence of a dissection following successful DCB treatment of a de novo coronary lesion may not be associated with an increased risk of LLL or TVF (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; NCT04619277).  相似文献   
998.
The Pierre Robin syndrome consists of micrognathia, pseudo-macroglossia, glossoptosis and a high arched or cleft palate. Difficult intubation of the trachea and associated abnormalities such as congenital heart disease are well known complications of this syndrome. Intraoral surgery (such as cleft palate repair and palatoplasty) can also be technically difficult for the surgeon resulting in prolonged retraction on the tongue with a mouth gag to provide adequate surgical exposure. We report a case where massive lingual oedema following a cleft palate repair resulted in life-threatening airway obstruction.  相似文献   
999.
1000.
Rats were exposed to TiO2 by inhalation exposure to concentrations of 0, 10, 50, and 250 mg/m3 for 6 hr/day, 5 days/week for 2 years. There were no abnormal clinical signs, body weight changes, or excess mortality in any exposed group. Exposed groups showed slight increases in the incidence of pneumonia, tracheitis, and rhinitis with squamous metaplasia in the anterior nasal cavity. The pulmonary response at 10 mg/m3 satisfied the biological criteria for a "nuisance dust." The lung reaction was characterized by dust-laden macrophage (dust cell) infiltration in the alveolar ducts and adjoining alveoli with hyperplasia of Type II pneumocytes. Rats at 50 and 250 mg/m3 exposure concentrations revealed a dose-dependent dust cell accumulation, a foamy macrophage response, Type II pneumocyte hyperplasia, alveolar proteinosis, alveolar bronchiolarization, cholesterol granulomas, focal pleurisy, and dust deposition in the tracheobronchial lymph nodes. Minute collagenized fibrosis occurred in the alveolar walls enclosing large dust cell aggregates. The pulmonary lesions with massive dust accumulation appeared to be the result of an overwhelmed lung clearance mechanism at 250 mg/m3 exposure. Bronchioloalveolar adenomas and cystic keratinizing squamous cell carcinomas occurred at 250 mg/m3 exposure, while no compound-related lung tumors were found in rats exposed to either 10 or 50 mg/m3. In addition to excessive dust loading in the lungs of rats exposed chronically at 250 mg/m3, the lung tumors were different from common human lung cancers in terms of tumor type, anatomic location, tumorigenesis, and were devoid of tumor metastasis. Therefore, the biological relevance of these lung tumors and other pulmonary lesions for man is negligible.  相似文献   
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