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101.
Cavitary pneumonia in an AIDS patient caused by an unusual Bordetella bronchiseptica variant producing reduced amounts of pertactin and other major antigens 下载免费PDF全文
Lorenzo-Pajuelo B Villanueva JL Rodríguez-Cuesta J Vergara-Irigaray N Bernabeu-Wittel M Garcia-Curiel A Martínez de Tejada G 《Journal of clinical microbiology》2002,40(9):3146-3154
Although Bordetella bronchiseptica can infect and colonize immunocompromised humans, its role as a primary pathogen in pneumonia and other respiratory processes affecting those patients remains controversial. A case of cavitary pneumonia caused by B. bronchiseptica in an AIDS patient is presented, and the basis of the seemingly enhanced pathogenic potential of this isolate (designated 814) is investigated. B. bronchiseptica was the only microorganism recovered from sputum, bronchoalveolar lavage fluid, and samples taken through the protected brush catheter. Unlike previous work reporting the involvement of B. bronchiseptica in cases of pneumonia, antibiotic treatment selected on the basis of in vitro antibacterial activity resulted in clearance of the infection and resolution of the pulmonary infiltrate. Although isolate 814 produced reduced amounts of several major antigens including at least one Bvg-activated factor (pertactin), the molecular basis of this deficiency was found to be BvgAS independent since the defect persisted after the bvgAS locus of isolate 814 was replaced with a wild-type bvgAS allele. Despite its prominent phenotype, isolate 814 displayed only a modest yet a significant deficiency in its ability to colonize the respiratory tracts of immunocompetent rats at an early time point. Interestingly, the antibody response elicited by isolate 814 in these animals was almost undetectable. We propose that isolate 814 may be more virulent in immunocompromised patients due, at least in part, to its innate ability to produce low amounts of immunogenic factors which may be required at only normal levels for the interaction of this pathogen with its immunocompetent natural hosts. 相似文献
102.
Tene V Malagón O Finzi PV Vidari G Armijos C Zaragoza T 《Journal of ethnopharmacology》2007,111(1):63-81
This paper reports the results of an ethnobotanical survey on the uses of medicinal plants by inhabitants of two southern Ecuadorian provinces, namely, Loja and Zamora-Chinchipe. In this region, two surviving ethnic groups, the Saraguros and the Shuars, and the descendants of a now extinct culture, the Paltas, have been identified. The present study reports a total of 275 plant species, having 68 different therapeutical uses. 相似文献
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León C Ruiz-Santana S Saavedra P Castro C Ubeda A Loza A Martín-Mazuelos E Blanco A Jerez V Ballús J Alvarez-Rocha L Utande-Vázquez A Fariñas O 《Intensive care medicine》2012,38(8):1315-1325
Purpose
To assess the value of (1→3)-β-d-glucan (BDG), Candida albicans germ tube antibody (CAGTA), C-reactive protein (CRP), and procalcitonin (PCT) levels for the diagnosis of invasive candidiasis (IC) and for differentiating Candida spp. colonization from infection in ICU patients with severe abdominal conditions (SAC).Methods
Prospective study of 176 non-neutropenic patients, with SAC at ICU admission, and expected to stay at least 7?days. Surveillance cultures and BDG, CAGTA, CRP, and PCT levels were performed on the third day of ICU stay and twice a week for four consecutive weeks. Patients were grouped into invasive candidiasis (IC), Candida colonization, and neither colonized/nor infected. The classification and regression tree (CART) analysis was used to predict IC in colonized patients. The discriminatory ability of the obtained prediction rule was assessed by the area under the ROC curve (AUC).Results
The probabilities of IC were 59.3?% for the terminal node of BDG greater than 259?pg/mL and 30.8?% for BDG less than 259?pg/mL and CAGTA positivity, whereas there was a 93.9?% probability in predicting the absence of IC for BDG less than 259?pg/mL and negative CAGTA. Using a cutoff of 30?% for IC probability, the prediction rule showed 90.3?% sensitivity, 54.8?% specificity, 42.4?% positive predictive value, and 93.9?% negative predictive value with an AUC of 0.78 (95?% confidence interval 0.76–0.81). Significant differences in CRP (p?=?0.411) and PCT (p?=?0.179) among the studied groups were not found.Conclusions
BDG with a positive test for CAGTA accurately differentiated Candida colonization from IC in patients with SAC, whereas CRP and PCT did not. 相似文献107.
Horrillo R Planagumà A González-Périz A Ferré N Titos E Miquel R López-Parra M Masferrer JL Arroyo V Clària J 《The Journal of pharmacology and experimental therapeutics》2007,323(3):778-786
In this study, we examined the relative contribution of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO), two major proinflammatory pathways up-regulated in liver disease, to the progression of hepatic inflammation and fibrosis. Separate administration of 4-[5-(4-chlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide (SC-236), a selective COX-2 inhibitor, and CJ-13,610, a 5-LO inhibitor, to carbon tetrachloride-treated mice significantly reduced fibrosis as revealed by the analysis of Sirius Red-stained liver sections without affecting necroinflammation. Conversely, combined administration of SC-236 and 4-[3-[4-(2-methylimidazol-1-yl)-phenylthio]]phenyl-3,4,5,6-tetrahydro-2H-pyran-4-carboxamide (CJ-13,610) reduced both necroinflammation and fibrosis. These findings were confirmed in 5-LO-deficient mice receiving SC-236, which also showed reduced hepatic monocyte chemoattractant protein 1 expression. Interestingly, SC-236 and CJ-13,610 significantly increased the number of nonparenchymal liver cells with apoptotic nuclei (terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive). Additional pharmacological profiling of SC-236 and CJ-13,610 was performed in macrophages, the primary hepatic inflammatory cell type. In these cells, SC-236 inhibited prostaglandin (PG) E2 formation in a concentration-dependent manner, whereas CJ-13,610 blocked leukotriene B4 biosynthesis. Of note, the simultaneous addition of SC-236 and CJ-13,610 resulted in a higher inhibitory profile on PGE2 biosynthesis than the dual COX/5-LO inhibitor licofelone. These drugs differentially regulated interleukin-6 mRNA expression in macrophages. Taken together, these findings indicate that both COX-2 and 5-LO pathways are contributing factors to hepatic inflammation and fibrosis and that these two pathways of the arachidonic acid cascade represent potential targets for therapy. 相似文献
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109.
Tatiane Calve Douglas Vicente Russo Júnior Ana Maria Forti Barela 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(1):64-69
Background
Exercises that could prevent gait impairment of older adults should be implemented in such a way that practitioners can keep motivation and adherence independent of older adults fitness levels.Objective
This study describes how younger and older adults use a non-pedal tricycle to transport their bodies along a pathway.Methods
Nine younger (24 ± 4.9 y) and nine older (66 ± 4.0 y) adults participated in this study. They moved along a straight pathway at a self-selected comfortable speed with reflective markers on their main lower limb landmarks. A computerized gait analysis system with infrared cameras was used to obtain kinematic data to calculate spatial-temporal parameters and lower limb angles.Results
Overall, participants from both groups were able to perform the task moving at a similar mean speed, with similar stride length and ankle joint excursion. Older adults had higher cadence (mean difference of 17 steps/min; 95% CI = 0.99–1.15) and hip excursion (mean difference of 12°; 95% CI = 28–33), longer stance duration (mean difference of 3.4%; 95% CI = 56.2–59.5), and lower knee excursion (mean difference of 6°; 95% CI = 47.9–53.8) than younger adults.Conclusion
Older adults were able to transport their body with a non-pedal tricycle with more hip and less knee excursion than younger adults. Professionals that work with the older population should look at and take into consideration the use of non-pedal tricycles in exercise protocols and investigate the long-term impacts. 相似文献110.
Comparative effects of estrogens plus androgens and tibolone on bone, lipid pattern and sexuality in postmenopausal women 总被引:4,自引:0,他引:4
Castelo-Branco C Vicente JJ Figueras F Sanjuan A Martínez de Osaba MJ Casals E Pons F Balasch J Vanrell JA 《Maturitas》2000,34(2):161-168
BACKGROUND: The main goals of estrogen replacement therapy (ERT) are the prevention of osteoporosis and cardioprotection and the improvement of quality of life (QL). Androgens and tibolone therapy may increase bone mineral density (BMD) to a greater extent than ERT and offer an increase in QL. Lipid and cardiovascular effects, however, are still a major concern. AIM: To evaluate whether the addition of a weak androgen to ERT may improve postmenopausal bone loss and sexual activity without adverse effects on lipid pattern and to compare these effects with those observed after tibolone therapy. SUBJECTS AND METHODS: This prospective study enrolled 120 surgical postmenopausal women; of these, 96 completed the 1-year follow-up. Patients were allocated to one of four groups. The first group (A; n = 23) received 4 mg of estradiol valerate plus 200 mg of enanthate of dihydroandrosterone im monthly. The second group (E; n = 26) received 50 microg/day of transdermal 17-b-estradiol continuously; the third (T; n = 23) received 2.5 mg of tibolone every day; and finally, the fourth group (C; n = 24) constituted a treatment-free control group. Bone mass (dual X-ray absorptiometry), serum total cholesterol, HDL, LDL, triglycerides, apolipoproteins A1 and B and sexual activity were evaluated before starting therapy and at the end of follow-up. RESULTS: All active treatment groups showed an increase in BMD. This increase was higher in the A treatment group (4.08% P < 0.01). Sexuality improved significantly with therapy; however, tibolone and androgens increased scores to a greater extent than ERT. Androgen therapy was associated with significant increases in total cholesterol, LDL and triglycerides. Cholesterol and LDL fall into groups E and T, HDL into groups A and T and triglycerides in group T only. CONCLUSION: The combined regimen of androgens and ERT increased vertebral bone mass and enhance sexual activity in postmenopausal women equal to that of tibolone and to a greater extent than ERT alone; its effects on lipids, however, are clearly adverse. 相似文献