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91.
92.
Dual role of interleukin-4 (IL-4) in pulmonary paracoccidioidomycosis: endogenous IL-4 can induce protection or exacerbation of disease depending on the host genetic pattern
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Arruda C Valente-Ferreira RC Pina A Kashino SS Fazioli RA Vaz CA Franco MF Keller AC Calich VL 《Infection and immunity》2004,72(7):3932-3940
Resistance to paracoccidioidomycosis, the most important endemic mycosis in Latin America, is thought to be primarily mediated by cellular immunity and the production of gamma interferon. To assess the role of interleukin-4 (IL-4), a Th2 cytokine, pulmonary paracoccidioidomycosis in IL-4-depleted susceptible (B10.A) and intermediate (C57BL/6) mice was studied. Two different protocols were used to neutralize endogenous IL-4 in B10.A mice: 1 mg of anti-IL-4 monoclonal antibody (MAb)/week and 8 mg 1 day before intratracheal infection with 10(6) Paracoccidioides brasiliensis yeast cells. Unexpectedly, both protocols enhanced pulmonary infection but did not alter the levels of pulmonary cytokines and specific antibodies. Since in a previous work it was verified that C57BL/6 mice genetically deficient in IL-4 were more resistant to P. brasiliensis infection, we also investigated the effect of IL-4 depletion in this mouse strain. Treatment with the MAb at 1 mg/week led to less severe pulmonary disease associated with impaired synthesis of Th2 cytokines in the lungs and liver of control C57BL/6 mice. Conversely, in IL-4-depleted C57BL/6 mice, increased levels of tumor necrosis factor alpha and IL-12 were found in the lungs and liver, respectively. In addition, higher levels of immunoglobulin G2a (IgG2a) and lower levels of IgG1 antibodies were produced by IL-4-depleted mice than by control mice. Lung pathologic findings were equivalent in IL-4-depleted and untreated B10.A mice. In IL-4-depleted C57BL/6 mice, however, smaller and well-organized granulomas replaced the more extensive lesions that developed in untreated mice. These results clearly showed that IL-4 can have a protective or a disease-promoting effect in pulmonary paracoccidioidomycosis depending on the genetic background of the host. 相似文献
93.
Laboratory detection of Haemophilus influenzae with decreased susceptibility to nalidixic acid, ciprofloxacin, levofloxacin, and moxifloxacin due to GyrA and ParC mutations
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Pérez-Vázquez M Román F Aracil B Cantón R Campos J 《Journal of clinical microbiology》2004,42(3):1185-1191
The detection of clinical isolates with decreased fluoroquinolone susceptibilities and a resistance mechanism is of epidemiological and clinical interest. We studied the susceptibilities of 62 clinical isolates and 2 American Type Culture Collection reference strains of Haemophilus influenzae to ciprofloxacin, levofloxacin, moxifloxacin, and nalidixic acid by the microdilution and disk diffusion methods. The ciprofloxacin MICs for 34 of the isolates were >/=0.12 micro g/ml (range, 0.12 to 32 micro g/ml), and the ciprofloxacin MICs for 28 matched control isolates were =0.06 micro g/ml. In addition, we sequenced the quinolone resistance-determining regions (QRDRs) of gyrA and parC of all strains. The log(2) MICs of all quinolones were plotted against the inhibition zone diameters. The MICs and inhibition zone diameters selected to screen for the resistance mechanism were based on the susceptibility distribution data and the presence or absence of amino acid changes in the QRDRs of GyrA and ParC. Strains for which ciprofloxacin MICs were =0.06 micro g/ml, levofloxacin and moxifloxacin MICs were =0.03 micro g/ml, and nalidixic acid MICs were =2.0 micro g/ml lacked modifications in the QRDR of GyrA. In contrast, all strains for which ciprofloxacin, levofloxacin, and moxifloxacin MICs were >/=0.5 micro g/ml and the vast majority of those for which nalidixic acid MICs were >/=32 micro g/ml exhibited amino acid changes in GyrA and ParC. Nalidixic acid and the other three fluoroquinolones studied could be used to screen H. influenzae isolates for the detection of decreased susceptibilities to quinolones due to the acquisition of two amino acid changes in the QRDRs of GyrA and ParC (sensitivity, >95%; specificity, >80%). 相似文献
94.
Carrozzo R Bornstein B Lucioli S Campos Y de la Pena P Petit N Dionisi-Vici C Vilarinho L Rizza T Bertini E Garesse R Santorelli FM Arenas J 《Human mutation》2003,21(4):453-454
Sixteen unrelated Southern European patients with the mitochondrial depletion syndrome (MDS) were analyzed for mutations in the TK2 and DGUOK genes. Three novel mutations were identified in TK2 (R183G, R254X, and 142insG). When we analyzed additional genes involved in the dNTPs pool, such as SLC25A19 (DNC) and NT5M (d-NT2), we did not detect mutations. The current study suggest that scanning the TK2, DGUOK, SLC25A19, and NT5M genes is likely to help about 10% of MDS families in terms of genetic counseling. Also, our findings indicate that genotype-phenotype correlations are not straightforward in MDS. 相似文献
95.
Mavale-Manuel S Alexandre F Duarte N Albuquerque O Scheinmann P Poisson-Salomon AS de Blic J 《Allergy》2004,59(4):388-393
BACKGROUND: Few studies have looked at risk factors for asthma in African children. We aimed to identify the risk factors associated with childhood asthma in Maputo (Mozambique). METHODS: This case-control study included 199 age-matched children (100 asthmatic and 99 nonasthmatic) who attended Maputo Central Hospital between January 1999 and July 2000. We collected information concerning their familial history of atopy, birth weight, environment and breast-feeding. Detailed information about morbidity and treatment was obtained for each asthmatic child. RESULTS: The children were aged between 18 months and 8 years; 60% were male. The asthmatic children were hospitalized more frequently than the nonasthmatic children (P < 0.0001). Most of the asthmatic children lived in the urban area of Maputo [odd ratio (OR) = 6.73, CI = 3.1-14.0, P < 0.0001], had a parental history of asthma (OR = 26.8, CI = 10.8-68.2, P < 0.0001) or rhinitis (OR = 4, CI = 1.2-13.3, P = 0.005), had at least parent who smoked and were weaned earlier than the nonasthmatic children (OR = 2.4, CI = 1.3-4.4, P < 0.001). CONCLUSION: Childhood asthma was strongly associated with a family history of asthma and rhinitis, the place of residence, having smokers as parents and early weaning from maternal breast milk. These results highlight the need to reassess the management of asthmatic children in Maputo. 相似文献
96.
Shwartzman reaction in streptozotocin-induced diabetic rats 总被引:1,自引:0,他引:1
A Campos S M Mauer A F Michael R L Vernier D M Brown Y Kim 《Laboratory investigation; a journal of technical methods and pathology》1984,50(5):565-570
The possibility that experimental diabetes could prepare for the generalized Shwartzman reaction was investigated in female Sprague-Dawley streptozotocin-induced diabetic rats. After 48 hours, 1 week, and 9 weeks of diabetes, the rats were injected with 2 mg/kg of endotoxin, and the animals were sacrificed 2, 4, 8, and 24 hours after endotoxin. Ninety percent of the diabetic animals given endotoxin developed massive glomerular capillary fibrin deposition accompanied by marked decrease in platelet count. The age- and sex-matched nondiabetic control rats had no such changes. This marked susceptibility to endotoxin, previously only reported in pregnant rats, was present as early as 1 week of diabetes. The degree of glycemic control greatly influenced the susceptibility of diabetic rats to the generalized Shwartzman reaction. Only 28% of the diabetic animals given insulin once daily (4.6 +/- 0.3 units, mean +/- SEM) and maintaining a blood glucose level of 269 +/- 19 mg/dl developed glomerular thrombi. In contrast, the diabetic animals that did not receive insulin and had a blood glucose level of 617 +/- 21 mg/dl all developed fibrin thrombi. We conclude that the diabetic state in rats induces a unique susceptibility to the generalized Shwartzman reaction following a single injection of endotoxin, which varies with the severity of the diabetic state. Although the pathogenesis is unclear, this phenomenon may reflect abnormalities in the glomerular capillary wall and/or the coagulation system that may be important in the development of microvascular complications. Furthermore, this phenomenon may, in the animal model, mirror the increased risk of the diabetic patient to intravascular coagulation with bacterial sepsis. 相似文献
97.
Cruz-Martínez A Arpa J Santiago S Pérez-Conde C Gutiérrez-Molina M Campos Y 《Electromyography and clinical neurophysiology》2004,44(1):35-38
Conventional EMG, nerve conduction studies and SFEMG were performed in 18 patients with various phenotypes of MD. 14 cases showed findings consistent with mild myopathy, 2 patients signs of sensory-motor axonal neuropathy and 2 cases a mixture of myopathy and axonal neuropathy. Motor unit fiber density was mild increased in 8 out of 13 tested cases. Jitter was abnormal in 10 out of 18 tested patients. Jitter abnormalities were not related to myopathic or neurogenic features in the EMG study, and may be observed in muscles without clinical weakness. The results suggest the existence of neuromuscular transmission disturbances in patients with MD. 相似文献
98.
G de Campos Freire L de Campos Pachelli P Cordeiro M Borrelli G M de Goes 《The Prostate》1986,8(1):87-92
Blood loss measurement in transurethral prostatic surgery (TUR) has been studied with the following objectives: (1) to measure the total lost volume (during surgery and 48 hours postoperatively); (2) to compare surgical bleeding and coagulogram alterations in benign prostatic hypertrophy (BPH) and prostatic carcinoma (CaP); (3) to establish the relationship between blood loss, duration of the procedure, and amount of resected tissue. The method of Jansen was used to measure blood loss, and the "coagulogram" included the following parameters: hematrocrit; prothrombin, recalcification, thrombin, and partial thromboplastin times; fibrinogen; platelets and fibrin split products. The study is based on TUR performed on 75 patients from whom a mean weight of 25.68 grams was resected resulting in a mean total bleeding volume of 305 ml. Blood loss over 400 ml was associated with surgical durations of 60 minutes or with resection of over 40 grams of tissue. There was a slight tendency for fibrinolysis in prostatic cancer, which could explain the relatively higher amount of blood loss observed in these cases. 相似文献
99.
Francisco A. O. Júnior Clara R. Ruiz Yohanna de Oliveira Marco A. V. Barros Alexandre S. Silva Maria S. B. Santos Vinícius J. B. Martins Camille M. Balarini Valdir A. Braga 《Nutrients》2021,13(3)
Exploring an alternative to improve the clinical management of hypertension, we tested the hypothesis that food supplementation with coconut oil (EVCO), alone or combined with aerobic exercise training, could exert an antihypertensive effect (primary outcome) in patients with stage 1 hypertension. Forty-five hypertensive volunteers of both genders participated in a placebo-controlled clinical trial. The volunteers were submitted to 24-hour ambulatory blood pressure monitoring, analysis of blood pressure variability (BPV), measurement of serum malondialdehyde (MDA) and nutritional assessment. Results indicate that EVCO consumption had no adverse effects. The supplementation did not increase the caloric intake compared with placebo, and the dietary constituents were similar between groups, except for the saturated fats, especially lauric acid. The analysis of blood pressure indicated absence of antihypertensive effect of EVCO alone or combined with physical training. Furthermore, no effects on blood pressure variability and oxidative stress were observed in the supplemented hypertensive patients. Thus, despite the results observed in pre-clinical studies, the current clinical study did not provide evidence to support the use of coconut oil as an adjuvant in the management of hypertension in humans. 相似文献
100.
Jernimo P. Martins Lucia C. Silva Matheus S. Nunes Gabriel Rübensam Jarbas R. Oliveira Rodrigo B. M. Silva Maria M. Campos 《Nutrients》2021,13(4)
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice. 相似文献