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排序方式: 共有508条查询结果,搜索用时 15 毫秒
61.
Ibrahim MM de Angelis R Lima AS Viana de Carvalho GD Ibrahim FM Malki LT de Paula Bichuete M de Paula Martins W Rocha EM 《PloS one》2012,7(3):e33775
Purpose
Fungi are a major cause of keratitis, although few medications are licensed for their treatment. The aim of this study is to observe the variation in commercialisation of antifungal eye drops, and to predict the seasonal distribution of fungal keratitis in Brazil.Methods
Data from a retrospective study of antifungal eye drops sales from the only pharmaceutical ophthalmologic laboratory, authorized to dispense them in Brazil (Opthalmos) were gathered. These data were correlated with geographic and seasonal distribution of fungal keratitis in Brazil between July 2002 and June 2008.Results
A total of 26,087 antifungal eye drop units were sold, with a mean of 2.3 per patient. There was significant variation in antifungal sales during the year (p<0.01). A linear regression model displayed a significant association between reduced relative humidity and antifungal drug sales (R2 = 0.17,p<0.01).Conclusions
Antifungal eye drops sales suggest that there is a seasonal distribution of fungal keratitis. A possible interpretation is that the third quarter of the year (a period when the climate is drier), when agricultural activity is more intense in Brazil, suggests a correlation with a higher incidence of fungal keratitis. A similar model could be applied to other diseases, that are managed with unique, or few, and monitorable medications to predict epidemiological aspects. 相似文献62.
63.
64.
LM de-Oliveira-Pinto CF Marinho TF Povoa EL de Azeredo LA de Souza LD Barbosa AR Motta-Castro AM Alves CA Ávila LJ de Souza RV da Cunha PV Damasco MV Paes CF Kubelka 《PloS one》2012,7(7):e38527
Little is known about the role of chemokines/chemokines receptors on T cells in natural DENV infection. Patients from DENV-2 and -3- outbreaks were studied prospectively during the acute or convalescent phases. Expression of chemokine receptor and activation markers on lymphocyte subpopulations were determined by flow cytometry analysis, plasma chemokine ligands concentrations were measured by ELISA and quantification of CCL5/RANTES(+) cells in liver tissues from fatal dengue cases was performed by immunochemistry. In the acute DENV-infection, T-helper/T-cytotoxic type-1 cell (Th1/Tc1)-related CCR5 is significantly higher expressed on both CD4 and CD8 T cells. The Th1-related CXCR3 is up-regulated among CD4 T cells and Tc2-related CCR4 is up-regulated among CD8 T cells. In the convalescent phase, all chemokine receptor or chemokine ligand expression tends to reestablish control healthy levels. Increased CCL2/MCP-1 and CCL4/MIP-1β but decreased CCL5/RANTES levels were observed in DENV-patients during acute infection. Moreover, we showed an increased CD107a expression on CCR5 or CXCR3-expressing T cells and higher expression of CD29, CD44(HIGH) and CD127(LOW) markers on CCR4-expressing CD8 T cells in DENV-patients when compared to controls. Finally, liver from dengue fatal patients showed increased number of cells expressing CCL5/RANTES in three out of four cases compared to three death from a non-dengue patient. In conclusion, both Th1-related CCR5 and CXCR3 among CD4 T cells have a potential ability to exert cytotoxicity function. Moreover, Tc1-related CCR5 and Tc2-related CCR4 among CD8 T cells have a potential ability to exert effector function and migration based on cell markers evaluated. The CCR5 expression would be promoting an enhanced T cell recruitment into liver, a hypothesis that is corroborated by the CCL5/RANTES increase detected in hepatic tissue from dengue fatal cases. The balance between protective and pathogenic immune response mediated by chemokines during dengue fever will be discussed. 相似文献
65.
Goldschmidt B Lopes CA Moura M Fasano DM Andrade MC Cysne LB Gonçalves MB Bravin JS Kugelmeier T Viana CF Silva FA Marinho AM 《Journal of medical primatology》2008,37(4):173-176
BACKGROUND: Agnathia is a rare malformation characterized by the absence of the mandible. METHODS: A male rhesus monkey with malformations was found dead and studied by internal examination, radiographs and histopathology. RESULTS: A case of a rare first branchial arch anomaly with agenesis of the mandible and tongue is presented. The animal also had visceral deformities. However, ears were normal in shape and only slightly low in position. The craniofacial malformations may reflect incomplete separation of the first branchial arch into its maxillary and mandibular processes. CONCLUSIONS: The association between the craniofacial and other corporal anomalies is unclear. 相似文献
66.
Pontes B Viana NB Campanati L Farina M Neto VM Nussenzveig HM 《European biophysics journal : EBJ》2008,37(2):121-129
We investigate properties of a reported new mechanism for cell–cell interactions, tunneling nanotubes (TNT’s). TNT’s mediate
actin-based transfer of vesicles and organelles and they allow signal transmission between cells. The effects of lateral pulling
with polystyrene beads trapped by optical tweezers on TNT’s linking separate U-87 MG human glioblastoma cells in culture are
described. This cell line was chosen for handling ease and possible pathology implications of TNT persistence in communication
between cancerous cells. Observed nanotubes are shown to have the characteristic features of TNT’s. We find that pulling induces
two different types of TNT bifurcations. In one of them, termed V-Y bifurcation, the TNT is first distorted into a V-shaped
form, following which a new branch emerges from the apex. In the other one, termed I-D bifurcation, the pulled TNT is bent
into a curved arc of increasingly broader span. Curves showing the variation of pulling force with displacement are obtained.
Results yield information on TNT structure and elastic properties.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
67.
Lery LM von Krüger WM Viana FC Teixeira KR Bisch PM 《Biochimica et biophysica acta》2008,1784(11):1578-1589
A proteomic view of G. diazotrophicus PAL5 at the exponential (E) and stationary phases (S) of cultures in the presence of low (L) and high levels (H) of combined nitrogen is presented. The proteomes analyzed on 2D-gels showed 131 proteins (42E+32S+29H+28L) differentially expressed by G. diazotrophicus, from which 46 were identified by combining mass spectrometry and bioinformatics tools. Proteins related to cofactor, energy and DNA metabolisms and cytoplasmic pH homeostasis were differentially expressed in E growth phase, under L and H conditions, in line with the high metabolic rate of the cells and the low pH of the media. Proteins most abundant in S-phase cells were stress associated and transporters plus transferases in agreement with the general phenomenon that binding protein-dependent systems are induced under nutrient limitation as part of hunger response. Cells grown in L condition produced nitrogen-fixation accessory proteins with roles in biosynthesis and stabilization of the nitrogenase complex plus proteins for protection of the nitrogenases from O(2)-induced inactivation. Proteins of the cell wall biogenesis apparatus were also expressed under nitrogen limitation and might function in the reshaping of the nitrogen-fixing G. diazotrophicus cells previously described. Genes whose protein products were detected in our analysis were mapped onto the chromosome and, based on the tendency of functionally related bacterial genes to cluster, we identified genes of particular pathways that could be organized in operons and are co-regulated. These results showed the great potential of proteomics to describe events in G. diazotrophicus cells by looking at proteins expressed under distinct growth conditions. 相似文献
68.
We have studied the effect of imidapril, an angiotensin-converting enzyme inhibitor, on streptozotocin-induced diabetic rats. A sequential euglycemic hyperinsulinemic clamp procedure was used (insulin infusion rates: 3 and 30 mU/kg BW/min) in 30 diabetic rats. The rats were divided in 6 groups: a control group, a control group with N-monomethyl-L-arginine (L-NMMA, 1 mg/kg/min, a nitric oxide synthase inhibitor) infusion, a streptozotocin-induced diabetic group, a diabetic group with L-NMMA infusion, a diabetic group involving imidapril infusion (5 microg/kg/min), and a diabetic group involving simultaneous imidapril and L-NMMA infusion. Glucose concentrations were maintained around 140 mg/dl during the clamp studies. Plasma insulin levels during the 3 and 30 mU/kg BW/min insulin infusions were 30 and 400 microU/ml, respectively. Glucose infusion rates (GIR) in STZ-induced diabetic rats showed a significant decrease compared to controls. At both insulin infusion rates, imidapril-infused diabetic rats showed an increased GIR, compared with the saline infused ones. There was no significant difference in GIR between L-NMMA and saline infusion in diabetic rats. Simultaneous infusion of imidapril and L-NMMA did not significantly decrease GIR with low-dose insulin infusion, but the increase in GIR induced by imidapril with high-dose insulin infusion was impaired by 100 % by L-NMMA infusion in diabetic rats. These results suggest that imidapril may improve insulin action, in part, via nitric oxide. 相似文献
69.
João Paulo Viana 《Hydrobiologia》2002,472(1-3):235-247
The regulation of the Jamari River advanced peak floods by 1–2 months and increased dry-season discharges from 60 to 200 m3 s–1, resulting in water levels approximately 1 m above those recorded before regulation. Daily variation in water level associated with fluctuations in electricity production by the dam propagated to the lower reaches of the tributary Candeias River. Dissolved oxygen (DO), temperature, pH, and conductivity measured over 1.5 years on three locations along the regulated and two free-flowing rivers indicated important alterations in the case of oxygen concentrations. DO levels shifted from saturated (7–8 mg l–1) during the flood season (when the spillways were open releasing epilimnetic water) to hypoxic (1.5–3 mg l–1) during the dry season (when the floodgates were closed and only hypolimnetic water used to run the turbines was feeding the river). Fluctuations in water level and variation in dissolved oxygen tended to be greater at the site closest to the dam, gradually attenuating downstream. Mitigation of the downstream effects of river regulation would require modifications in the operation of the dam. 相似文献
70.
Piccoli-Valle Roberta Hilsdorf Brandi Igor Viana Silva Daison Olzany Vieira Passos Frederico José 《World journal of microbiology & biotechnology》2001,17(5):433-437
Penicillium griseoroseum cultured in the presence of sucrose and yeast extract produces pectin lyase (EC 4.2.2.10) (PL) in the absence of its natural inducer pectin. This fungus was cultured in a fermenter at an aeration rate of 0.5 l/min for the first 25 h and 1.0 l/min for the remainder of the culture period, and at a stirring rate of 200 rev/min for the entire culture period. Fungal spores were inoculated directly into the fermenter at a final concentration of 5 × 104 spores/ml. The fungus was cultured in minimal medium supplemented with powdered dehydrated sugar cane juice, producing PL without added yeast extract. Maximum PL activity (0.067 IU/ml) was obtained after 65 h in batch culture. Pellet morphology of the mycelia made it possible to carry out three cycles of repeated batch culture. The same medium was used for renewal as for the single batch culture. The initial cycle was 53 h, after which approximately 0.103 IU/ml of PL was obtained. After this period, the medium was renewed and fermentation continued for two more cycles, which lasted approximately 20 h. Activity of PL obtained in the second cycle was approximately 0.118 IU/ml and in the third, approximately 0.109 IU/ml. 相似文献