999 resultados para Corresponding aldehydes


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LipL32 is the major leptospiral outer membrane lipoprotein expressed during infection and is the immunodominant antigen recognized during the humoral immune response to leptospirosis in humans. In this study, we investigated novel aspects of LipL32. In order to define the immunodominant domains(s) of the molecule, subfragments corresponding to the N-terminal, intermediate, and C-terminal portions of the UpL32 gene were cloned and the proteins were expressed and purified by metal affinity chromatography. Our immunoblot results indicate that the C-terminal and intermediate domains of LipL32 are recognized by sera of patients with laboratory-confirmed leptospirosis. An immunoglobulin M response was detected exclusively against the LipL32 C-terminal fragment in both the acute and convalescent phases of illness. We also evaluated the capacity of LipL32 to interact with extracellular matrix (ECM) components. Dose-dependent, specific binding of LipL32 to collagen type IV and plasma fibronectin was observed, and the binding capacity could be attributed to the C-terminal portion of this molecule. Both heparin and gelatin could inhibit LipL32 binding to fibronectin in a concentration-dependent manner, indicating that the 30-kDa heparin-binding and 45-kDa gelatin-binding domains of fibronectin are involved in this interaction. Taken together, our results provide evidence that the LipL32 C terminus is recognized early in the course of infection and is the domain responsible for mediating interaction with ECM proteins.

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The current study investigated the occurrence of ticks and their rickettsiae in the Serra do Mar State Park, which encompasses one of the largest Atlantic rain forest reserves of Brazil. From July 2008 to June 2009, a total of 2,439 ticks (2,196 free living and 243 collected on hosts) was collected, encompassing the following 13 species: Amblyomma aureolatum (Pallas), Amblyomma brasiliense Aragao, Amblyomma dubitatum Neumann, Amblyomma fuscum Neumann, Amblyomma incisum Neumann, Amblyomma longirostre (Koch), Amblyomma naponense (Packard), Amblyomma nodosum Neumann, Amblyomma ovale Koch, Haemaphysalis juxtakochi Cooley, Ixodes aragaoi Fonseca, Lodes loricatus Neumann, and Rhipicephalus sanguineus (Latreille). Ticks were submitted to polymerase chain reaction assays targeting portions of the rickettsial genes gltA and ompA. Polymerase chain reaction products were DNA sequenced and compared with corresponding sequences available in GenBank. Rickettsia bellii, a rickettsia of unknown pathogenicity, was detected in one A. aureolatum, one A. ovate, and three A. incisum specimens. At least 8.8% (3/34) of the free-living A. ovale ticks, 13.6% (8/59) of the A. ovale ticks collected from dogs, and 1.9% (1/54) of the R. sanguineus (Latreille) ticks were found to be infected by Rickettsia sp strain Atlantic rain forest, a novel strain that has been shown to cause an eschar-associated spotted fever in the state of Sao Paulo. Our results suggest that A. ovale is the vector of Rickettsia sp strain Atlantic rain forest in the state of Sao Paulo.

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Males, females, and larvae of Carios fonsecai sp. nov. are described from free-living ticks collected in a cave at Bonito, state of Mato Grosso do Sul, Brazil. The presence of cheeks and legs with micromammillate cuticle makes adults of C. fonsecai morphologically related to a group of argasid species (mostly bat-associated) formerly classified into the subgenus Alectorobius, genus Ornithodoros. Examination of larvae indicates that C. fonsecai is clearly distinct from most of the previously described Carios species formerly classified into the subgenus Alectorobius, based primarily on its larger body size, dorsal setae number, dorsal plate shape, and hypostomal morphology. On the other hand, the larva of C. fonsecai is most similar to Carios peropteryx, and Carios peruvianus, from which differences in dorsal plate length and width, tarsal setae, and hypostome characteristics are useful for morphological differentiation. The mitochondrial 16S rDNA sequence of C. fonsecai showed to be closest (85-88% identity) to several corresponding sequences of different Carios species available in GenBank. Bats identified as Peropteryx macrotis and Desmodus rotundus were found infested by C. fonsecai larvae in the same cave where the type series was collected. C. fonsecai showed to be aggressive to humans in the laboratory.

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Free-living adult Amblyomma incisum ticks were collected in an Atlantic rainforest area at Intervales State Park, State of Sao Paulo, Brazil. From an A. incisum specimen, rickettsiae were successfully isolated in Vero cell culture by the shell vial technique. Rickettsial isolation was confirmed by optical microscopy, transmission electron microscopy, and PCRs targeting portions of the rickettsial genes gltA, htrA, rrs, and sca1 on infected cells. Fragments of 1,089, 457, 1,362, and 443 nucleotides of the gltA, htrA, rrs, and sca1 genes, respectively, were sequenced. By BLAST analysis, the partial sequence of rrs of the A. incisum rickettsial isolate was closest to the corresponding sequence of Rickettsia bellii (99.1% similarity). The gltA partial sequence was closest to the corresponding sequences of ""Candidatus Rickettsia tarasevichiae"" (96.1% similarity) and Rickettsia canadensis (95.8% similarity). The htrA partial sequence was closest to the corresponding sequence of R. canadensis (89.8% similarity). The sca1 partial sequence was closest to the corresponding sequence of R. canadensis (95.2% similarity). Since our rickettsial isolate was genetically distinct from other Rickettsia species, we propose a new species designated Rickettsia monteiroi sp. nov. Phylogenetic analyses indicated that R. monteiroi belongs to the canadensis group within the genus Rickettsia, together with the species R. canadensis and ""Candidatus R. tarasevichiae"". Little or no antibody cross-reaction was observed between sera of R. monteiroi-inoculated guinea pigs and R. bellii-, Rickettsia rickettsii-, or R. canadensis-inoculated guinea pigs.

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From May 2007 to March 2008, blood samples were collected from 92 healthy dogs living in 21 households (17 farms in rural area, and 4 homes in urban area) in 6 counties of the State of Espirito Santo, southeastern Brazil. In addition, ticks were collected from these dogs. A mean of 4.4 +/- 3.0 dogs (range: 1-12) were sampled per household; 78 and 14 dogs were from rural and urban areas, respectively. Polymerase chain reaction (PCR) designed to amplify fragments of the 18S rDNA gene of Babesia spp or Hepatozoon spp revealed amplicons of the expected size in 20 (21.7%) dogs for Babesia, and 54 (58.7%) dogs for Hepatozoon. All Babesia-positive dogs were also Hepatozoon-positive. Among the 21 households, 15 (71.4%) from 3 counties had at least one PCR-positive dog, including 13 farms (rural area) and 2 homes (urban area). A total of 40 PCR products from the Hepatozoon-PCR, and 19 products from the Babesia-PCR were submitted to DNA sequencing. All generated sequences from Hepatozoon-PCR were identical to each other, and to corresponding 18S rDNA sequences of H. canis in GenBank. Surprisingly, all generated sequences from the Babesia PCR were also identical to corresponding 18S rDNA sequences of H. canis in GenBank. Dogs from 10 rural and 2 urban households were found infested by Rhipicephalus sanguineus ticks. Immature of Amblyomma cajennense ticks were found in dogs from only 4 rural households (also infested by R. sanguineus). All but one household with R. sanguineus-infested dogs had at least one Hepatozoon-infected dog. Statistical analysis showed that the presence of ticks (i.e. R. sanguineus) infesting dogs in the households was significantly (P < 0.05) associated with at least one PCR-positive dog. There was no significant association (P > 0.05) between PCR-positive dogs and urban or rural households. Canine hepatozoonosis caused by H. canis is a high frequent infection in Espirito Santo, Brazil, where it is possibly vectored by R. sanguineus. Since all infected dogs were found apparently healthy, the pathogenicity of H. canis for dogs in Espirito Santo is yet to be elucidated. (C) 2009 Elsevier B.V. All rights reserved.

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The rickettsial infections in 174 Amblyomma nodosum found on passeriform birds in the Atlantic forest, eastern Brazil, have recently been evaluated. Rickettsiae were successfully isolated from two ticks, using cultures of Vero cells. Both isolates were molecularly characterised, using the rickettsial genes gltA and htrA and, when possible, also ompA and ompB. Portions of the gltA and htrA genes from one of the rickettsial isolates were found be closely match the corresponding GenBank sequences for Rickettsia bellii, with 99.9% and 100% homology, respectively. This isolate was named R. bellii strain Pontal. Portions of the gltA, htrA and ompB genes from the second isolate most closely matched the corresponding sequences of R. parkeri, whereas a portion of the ompA gene from this isolate was closest to the relevant sequence of Rickettsia sp. strain COOPERI (which has been considered to be a strain of R. parkeri in Brazil). The second isolate was named R. parkeri strain NOD. Further investigation of the 172 ticks from which isolates were not recovered revealed R. parkeri strain NOD in 40 and R. bellii strain Pontal in nine, giving overall infection prevalences of 23.6% (41/174) and 5.7% (10/174), respectively. This appears to be the first report of R. bellii and R. parkeri in A. nodosum.

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The effects in broiler chicks of treatment with a competitive exclusion (CE) product, an experimental dietary probiotic, and the abiotic beta-glucan on cecal colonization, organ invasion, and serum and intestinal IgG and IgA levels to Salmonella challenge was evaluated. Four groups of 1-d-old chicks were treated by oral gavage on d 1 with an appropriate dose of a commercial CE product. Three groups received daily doses of probiotic, beta-glucan, or both, for 6 d. Three other groups were fed daily from d 1 onwards with probiotic, beta-glucan, or both. Subgroups of 30 chicks from each group were challenged on d 1, 9, 16, or 23 with 10(7) cfu/mL of Salmonella Typhimurium (1769NR) and killed 7 d later. Control groups were maintained untreated and remained unchallenged (negative control), or were challenged with Salmonella Typhimurium (1769NR; positive control), as described above. Cecum, liver, and spleen samples were examined for the presence of Salmonella, whereas serum and intestinal fluid samples were assayed for total antibody (IgG and IgA) concentrations. Data were analyzed by 1-way ANOVA, and means were compared using Duncan`s multiple range test. In comparison with other treatments, those involving CE product and beta-glucan, with or without probiotic during the first week, resulted in a superior inhibition of cecal colonization and organ invasion by Salmonella and also offered a higher level of protection (P < 0.05). During the second week, treatments containing experimental dietary probiotic and beta-glucan, with or without CE product, resulted in an inhibition of liver invasion (P < 0.05). The IgA levels were significantly higher (P < 0.05) in intestinal fluid compared with serum, whereas IgG had low levels. The results in the first and third week indicate that combination treatments involving CE product, probiotic, and beta-glucan are a more effective control of Salmonella colonization than the corresponding individual preparations.

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Bovine Herpesvirus type-5 (BoHV-5), which is potentially neuropathogenic, was recently described to be related with reproductive disorders in cows. The objective was to elucidate mechanisms involved in propagation of BoHV-5 in embryonic cells. For this purpose, bovine embryos produced in vitro were assayed for apoptotic markers after experimental infection of oocytes, in vitro fertilization, and development. Host DNA fragmentation was detected with a TUNEL assay, expression of annexin-V was measured with indirect immunofluorescence, and viral DNA was detected with in situ hybridization. Infective BoHV-5 virus was recovered from embryos derived from exposed oocytes after two consecutive passages on Madin-Darby bovine kidney (MDBK) cells. The viral DNA corresponding to US9 gene, localized between nucleotides 126243 to 126493, was detected in situ and amplified. There was no significant difference between the ratio of TUNEL stained nuclei and total cells in good quality blastocysts (0.87 +/- 0.05, mean SD), but there were differences (P < 0.05) between infected (0.18 +/- 0.05) and uninfected blastocysts (0.73 +/- 0.07). The Annexin-V label was more intense in uninfected embryos (0.79 +/- 0.04; P < 0.05). The quality of infected and uninfected embryos was considered equal, with no significant effect on embryonic development. In conclusion, we inferred that BoHV-5 infected bovine oocytes, replicated, and suppressed some apoptotic pathways, without significantly affecting embryonic development. (C) 2010 Elsevier Inc. All rights reserved.

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This study evaluated the effect of the C-factor and dentin preparation method (DPM) in the bond strength (BS) of a mild self-etch adhesive; the study also observed the SEM superficial aspects of the corresponding smear layer. For purposes of this study, 25 molars (n=5) were used in a bond strength test. The molars were divided into two parts (buccal and lingual): one part received a Class V cavity (C-factor=3) and the other received a flat surface (C-factor=0) with the same bur type (coarse diamond or carbide bur and fine diamond or carbide bur), both within the same dentin depth. Five teeth were prepared with wet 60-grit and 600-grit SiC papers. After restoration with Clearfil SE Bond, microtensile beans (0.8 mm(2)) were prepared and tested after 24 hours in a universal testing machine (0.5 mm/minute). An additional two teeth for each DPM were prepared for SEM evaluation of the smear layer superficial aspects. The BS values were submitted to one-way ANOVA, considering only the DPM (flat surfaces) and two-way ANOVA (C-Factor x DPM, considering only burs) with p=0.05. Although the DPM in the flat surfaces was not significant, the standard deviations of carbide bur-prepared specimens were markedly lower. The BS was significantly lower in cavities. The fine carbide bur presented the most favorable smear layer aspect. It was concluded that different dentin preparation methods could not prevent the adverse effect in bond strength of a high C-factor. A coarse cut carbide bur should be avoided prior to a mild self-etch adhesive, because it adversely affected bond strength. In contrast, a fine cut carbide bur provided the best combination: high bond strength with low variability, which suggests a more reliable bond strength performance.

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Metalloproteinases (MMPs) have been implicated with metabolism of collagen in physiological and pathological processes in human dentine. As bovine teeth have been used as a substitute for human teeth in laboratory analysis, this study evaluated the activity of MMP-2 and -9 in bovine versus human dentine. Bovine and human dentine fragments, from crowns and roots, were powderized. Protein extraction was performed by two protocols: a neutral extraction with guanidine-HCl/EDTA (pH 7.4) and an acidic extraction with citric acid (pH 2.3). Gelatinolytic activities of extracts were revealed by zymography. MMP-2 and -9 were detected in crown and root dentine from bovine and human teeth. Total activities of MMP-2 were 11.4 +/- 2.2, 14.6 +/- 2.0, 9.7 +/- 1.2 and 12.4 +/- 0.9 ng/ml for bovine root, human root, bovine crown and human crown dentine, respectively. Corresponding activities for MMP-9 were 14.9 +/- 2.0, 15.3 +/- 1.3, 15.4 +/- 1.3 and 15.5 +/- 1.3 ng/ml, respectively. Bovine dentine was found to be a reliable substrate for studies involving the activity of MMP-2 and -9. Copyright (C) 2011 S. Karger AG, Basel

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Objective. To evaluate the effect of two additives, aldehyde or diketone, on the wear, roughness and hardness of bis-GMA-based composites/copolymers containing TEGDMA, propoxylated bis-GMA (CH(3)bis-GMA) or propoxylated fluorinated bis-GMA (CF(3)bis-GMA). Methods. Fifteen experimental composites and 15 corresponding copolymers were prepared combining bis-GMA and TEGDMA, CH3bis-GMA or CF3bis-GMA, with aldehyde (24mol% and 32 mol%) or diketone (24 mol% and 32 mol%) totaling 30 groups. For composites, hybrid treated filler (barium aluminosilicate glass/pyrogenic silica; 60 wt%) was added to monomer mixtures. Photopolymerization was affected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Wear (W) test was conducted in a toothbrushing abrasion machine (n = 6) and quantified using a profilometer. Surface roughness (R) changes, before and after abrasion test, were determined using a rugosimeter. Microhardness (H) measurements were performed for dry and wet samples using a Knoop microindenter (n = 6). Data were analyzed by one-way ANOVA and Tukey`s test (alpha = 0.05). Results. Incorporation of additives led to improved W and H values for bis-GMA/TEGDMA and bis-GMA/CH(3)bis-GMA systems. Additives had no significant effect on the W and H changes of bis-GMA/CF(3)bis-GMA. With regard to R changes, additives produced decreased values for bis-GMA/CH3bis-GMA and bis-GMA/CF3bis-GMA composites. Bis-GMA/TEGDMA and bis-GMA/CH(3)bis-GMA copolymers with additives became smoother after abrasion test. Significance. The findings correlate with additives ability to improve degree of conversion of some composites/copolymers thereby enhancing mechanical properties. Published by Elsevier Ltd on behalf of Academy of Dental Materials

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The objectives of this study were to investigate the presence and distribution of substance P and neurokinin 1 receptor in oral premalignant epithelium and their relation with the presence of dysplasia, and to analyze whether the expression of substance P can be considered an early oncogenic event in oral carcinogenesis. Substance P and neurokinin I receptor expression was immunohistochemically studied in 83 oral carcinomas and adjacent nontumor epithelia. The presence and degree of epithelial dysplasia was assessed according to WHO criteria. The nuclear, cytoplasmic, and membrane expression of substance P and the cytoplasmic and membrane expression of neurokinin 1 receptor were assessed in tumor and adjacent non-tumor epithelium. Nuclear and cytoplasmic expression of substance P in non-tumor epithelium was significantly associated with the presence of epithelial dysplasia (p<0.001) and carcinoma in. situ (p=0.021). Nuclear, cytoplasmic, and membrane expressions of substance P in non-tumor epithelium were significantly (p<0.001) associated with its expression in the corresponding tumor. These findings suggest that substance P plays a role in early oral carcinogenesis by promoting the proliferation and growth of premalignant fields.

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The need for methods of indirectly estimating migration flows is particularly important in developing countries, where migration data are often incomplete and inaccurate. This paper focuses on the use of an indirect internal migration estimation method applied to Mexican and Indonesian census data. It shows that the mobility propensities of infants can be used to infer the corresponding propensities of all other age groups. However, the promise of this method is reduced in instances of inadequate data, and great care must be taken to identify outlying values in the data and to correct obviously erroneous patterns. Future work increasingly will be directed to this issue.

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Objective: The objective of the study is to investigate the results of the newborn hearing screening program carried out in a Public Hospital in Brazil, in the first 3 years regarding: (1) the prevalence of hearing impairment; (2) the influence of the universal hearing screening program on the age at which the diagnosis of hearing loss is defined; (3) the cost effectiveness of the program; (4) the outcomes, in terms of the age in which the hearing rehabilitation started. Methods: A descriptive study of the first 3 years after starting the universal newborn hearing screening in a Public Hospital of Bauru, Sao Paulo state, Brazil. The screening method consists of a two-stage screening approach with transient otoacoustic emissions (TOAE), conducted by an audiologist. If the outcome in the second-stage screening is REFER, the infant is submitted to diagnostic follow-up testing and intervention at the Audiology and Speech Pathology Clinic at the University of Sao Paulo, campus of Bauru. The evaluation of the costs of the universal newborn hearing screening program per each screened newborn (around 4000/year) was done based on a proposal by the National Center for Hearing Assessment and Management, of the Utah State University, United States of America. Results: 11,466 newborns were submitted to hearing screening, corresponding to 90.52% of the living newborns. The prevalence of sensorineural hearing loss was 0.96:1000. Of the 11 children with sensorineural hearing loss, eight children received hearing aids and five started the therapeutic process before the age of 1. Currently, four children between the ages of 11 months and 2 years old were submitted to cochlear implant surgery. The cost of hearing screening was US$7.00 and the annual cost of the universal newborn hearing screening program was US$26,940.47. Conclusion: The hospital-based universal newborn hearing screening carried out through the Brazilian National Health System is viable, with promising results. However, in a country such as Brazil, which presents large socio-economic differences, the same type of analyses should be performed in several regions, so as to take into account specific aspects, to implement the newborn hearing screening along with the Public System. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

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Purpose: The objective of the present in situ study was to evaluate the influence of dental plaque on human enamel erosion. Materials and Methods: Thirteen volunteers wore acrylic palatal devices with four enamel specimens that were prepared from freshly extracted impacted human third permanent molars (4 x 4 mm), randomly selected and distributed into two vertical rows, corresponding to the following groups: GI, erosion of dental plaque-free samples, and GII, erosion of dental plaque-covered samples. For the formation of dental plaque, the specimens were placed 1 mm below the level of the appliance and covered with a plastic mesh to allow the accumulation of dental plaque. The palatal device was continuously worn by the volunteers for 14 consecutive days and then immersed in a soft drink (Coca-Cola (R), 150 ml) for 5 min, three times a day. Half of the surfaces of specimens were coated with nail varnish for profilometry tests. The study variables included the depth of enamel surface wear (profilometer, vertical ranges in pm) and the percentage of superficial microhardness change (%SMHC). Data were analysed using the t test (P < 0.05). Results: The %SMHC and depth of enamel surface wear were significantly higher for GI (-87.82% +/- 3.66 and 4.70 mu m +/- 1.65) than for GII (-13.79% +/- 4.22 and 0.14 mu m +/- 0.03). Conclusions: It was concluded that the dental plaque formed in situ was able to protect the enamel surface against erosion by a cola soft drink, thus reducing the depth of enamel surface wear and the %SMHC.