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41.
The impact of transfusion of leucodepleted platelet concentrates (PCs) on cytomegalovirus (CMV) disease was assessed in 215 allogeneic (145 unrelated and 70 related donor) transplants over 3 years. In 43%, both donor and patient were CMV seronegative (CMV-/-). All received CMV-seronegative red cells and random leucodepleted PCs. No CMV disease occurred in any CMV-/- (low risk) transplant. CMV infection occurred in 31 seropositive patients (26%); 13 died and five deaths were attributable to CMV disease. When compared with historical controls, who received CMV-seronegative PCs, we found no difference in transfusion-acquired CMV in the current cohort.  相似文献   
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OBJECTIVE: Arterial remodeling aims to maintain a constant circumferential wall stress (sigmac). A failing remodeling process is associated with stroke. Data on the relationship between chronic kidney disease and arterial remodeling are scarce. METHODS: We investigated the association between a lower glomerular filtration rate (GFR) and microalbuminuria with arterial remodeling of the common carotid artery (CCA) in a population-based study of 806 patients. CCA properties including intima-media thickness and interadventitial diameter (IAD) were assessed. Lumen diameter, circumferential wall tension (CWT), and circumferential wall stress (sigmac) were calculated. GFR was estimated (eGFR) by the Modification of Diet in Renal Disease formula. Albuminuria was expressed as urinary albumin/creatinine ratio. RESULTS: Mean eGFR was 60.3 (+/-10.8) ml/min/1.73 m2; median urinary albumin/creatinine ratio was 0.57 (range 0.10-26.6 mg/mmol). After adjustment for age, sex, glucose tolerance status, and prevalent cardiovascular disease, eGFR was not independently associated with CCA properties. A greater urinary albumin/creatinine ratio (per quartile) was associated with a greater lumen diameter [regression coefficient beta with 95% confidence interval, 0.14 (0.08-0.20; P < 0.01)], IAD [0.15 (0.09-0.21; P < 0.01)], CWT [0.95 (0.52-1.38; P < 0.01)], and sigmac [1.7 (0.5-2.9; P < 0.01)] but not with a greater IMT [0.01 (-0.002-0.02; P = 0.12)]. Additional adjustments for mean arterial pressure, pulse pressure, and eGFR did not change the results. CONCLUSION: Greater albuminuria is independently associated with an increase in lumen diameter and IAD of the CCA. In addition, greater albuminuria is associated with a maladaptive carotid remodeling process as shown by an increase in CWT and sigmac. These findings may explain, why microalbuminuria is associated with a greater risk of cardiovascular disease and especially stroke.  相似文献   
43.
A total of 316 samples of nasopharyngeal aspirate from infants up to two years of age with acute respiratory-tract illnesses were processed for detection of respiratory syncytial virus (RSV) using three different techniques: viral isolation, direct immunofluorescence, and PCR. Of the samples, 36 (11.4%) were positive for RSV, considering the three techniques. PCR was the most sensitive technique, providing positive findings in 35/316 (11.1%) of the samples, followed by direct immunofluorescence (25/316, 7.9%) and viral isolation (20/315, 6.3%) (p < 0.001). A sample was positive by immunofluorescence and negative by PCR, and 11 (31.4%) were positive only by RT-PCR. We conclude that RT-PCR is more sensitive than IF and viral isolation to detect RSV in nasopharyngeal aspirate specimens in newborn and infants.  相似文献   
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AIDS and Behavior - A better understanding of the social-structural factors that influence HIV vulnerability is crucial to achieve the goal of ending the HIV epidemic by 2030. Given the role of...  相似文献   
46.
Accurate noninvasive tests for diagnosing Helicobacter pylori infection in very young children are strongly required. We investigated the agreement between the [13C]urea breath test ([13C]UBT) and a monoclonal ELISA (HpSA) for detection of H. pylori antigen in stool. From October 2007 to July 2011, we enrolled 414 infants (123 from Brazil and 291 from Peru) of ages 6 to 30 months. Breath and stool samples were obtained at intervals of at least 3 months from Brazilian (n = 415) and Peruvian (n = 908) infants. [13C]UBT and stool test results concurred with each other in 1,255 (94.86%) cases (kappa coefficient = 0.90; 95% confidence interval [CI] = 0.87 to 0.92). In the H. pylori-positive group, delta-over-baseline (DOB) and optical density (OD) values were positively correlated (r = 0.62; P < 0.001). The positivity of the tests was higher (P < 0.001; odds ratio [OR] = 6.01; 95% CI = 4.50 to 8.04) in Peru (546/878; 62.2%) than in Brazil (81/377; 21.5%) and increased with increasing age in Brazil (P = 0.02), whereas in Peru it decreased with increasing age (P < 0.001). The disagreement between the test results was associated with birth in Brazil and female gender but not with age and diarrhea. Our results suggest that both [13C]UBT and the stool monoclonal test are reliable for diagnosing H. pylori infection in very young children, which will facilitate robust epidemiological studies in infants and toddlers.  相似文献   
47.
Despite recent advances in understanding the biological basis of prostate cancer (PCa), the management of this disease remains a challenge. Chemoprotective agents have been used to protect against or eradicate prostate malignancies. Here, we investigated the protective effect of γ‐tocopherol on N‐methyl‐N‐nitrosourea (MNU)‐induced epithelial dysplasia in the rat ventral prostate (VP). Thirty‐two male Wistar rats were divided into four groups (n = 8): control (CT): healthy control animals fed a standard diet; control+γ‐tocopherol (CT+γT): healthy control animals without intervention fed a γ‐tocopherol‐enriched diet (20 mg/kg); N‐methyl‐N‐nitrosourea (MNU): rats that received a single dose of MNU (30 mg/kg) plus testosterone propionate (100 mg/kg) and were fed a standard diet; and MNU+γ‐tocopherol (MNU+γT): rats that received the same treatment of MNU plus testosterone and were fed with a γ‐tocopherol‐enriched diet (20 mg/kg). After 4 months, the VPs were excised to evaluate morphology, cell proliferation and apoptosis, as well as cyclooxygenase‐2 (Cox‐2), glutathione‐S‐transferase‐pi (GST‐pi) and androgen receptor (AR) protein expression, and matrix metalloproteinase‐9 (MMP‐9) activity. An increase in the incidence of epithelial dysplasias, such as stratified epithelial hyperplasia and squamous metaplasia, in the MNU group was accompanied by augmented cell proliferation, GST‐pi and Cox‐2 immunoexpression and pro‐MMP‐9 activity. Stromal thickening and inflammatory foci were also observed. The administration of a γ‐tocopherol‐enriched diet significantly attenuated the adverse effects of MNU in the VP. The incidence of epithelial dysplasia decreased, along with the cell proliferation index, GST‐pi and Cox‐2 immunoexpression. The gelatinolytic activity of pro‐MMP‐9 returned to the levels observed for the CT group. These results suggest that γ‐tocopherol acts as a protective agent against MNU‐induced prostatic disorders in the rat ventral prostate.  相似文献   
48.
This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg?mL?1, larvicidal activity with LC50 ranging from 25.5 to 94.6 μg?mL?1, and pupicidal action with PC50 ranging from 276.8 to over 500 μg?mL?1. Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg?mL?1, respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50?>?6,000 mg.kg?1) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg?1, respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals.  相似文献   
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Abstract

During the last decades, studies exploring the role of microorganisms inhabiting human body in different scenarios have demonstrated the great potential of modulating them to treat and prevent diseases. Among the most outstanding applications, probiotics have been used for over a century to treat infections and inflammation. Despite the beneficial role of other probiotics, Lactobacillus and Bifidobacterium species are the most frequently used, and have been effective as a therapeutic option in the treatment/prevention of dental caries, periodontal diseases, urogenital infections, and gastrointestinal infections. Additionally, as gastrointestinal tract harbors a great diversity of microbial species that directly or indirectly modulate host metabolism and immune response, the influence of intestinal microbiota, one of the targets of therapies using probiotics, on the biology of immune cells can be explored to treat inflammatory disorders or immune-mediated diseases. Thus, it is not surprising that probiotics have presented promising results in modulating human inflammatory diseases such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease, among others. Hence, the purpose of this review is to discuss the potential of therapeutic approaches using probiotics to constrain infection and development of inflammation on human subjects.  相似文献   
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