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31.
Oliveira GG Navarro IT Freire RL Belitardo DR Silveira LH Camargo ZP Itano EN Ono MA 《Mycopathologia》2012,173(1):63-68
The objective of this study was to evaluate the prevalence of antibodies against Paracoccidioides brasiliensis in sheep from Guarapuava, Paraná State, Brazil. The seroepidemiological study was carried out in 262 sheep. The samples were
analyzed by ELISA and immunodiffusion test using P. brasiliensis gp43 and exoantigen as antigens, respectively. Initially, two sheep were immunized with P. brasiliensis to evaluate whether contact with the fungal cells could induce a humoral immune response against gp43 and exoantigen from
P. brasiliensis. Both animals produced antibodies against gp43 and exoantigen, the main antigens used for diagnosis and seroepidemiology
of paracoccidioidomycosis. A reactivity of 37% was observed to the P. brasiliensis gp43 antigen by ELISA although no reactivity had been observed by the immunodiffusion test. Sheep under extensive grazing
system showed higher frequency of positivity to P. brasiliensis (P ≤ 0.05) than those under intensive and semi-intensive systems. These data suggest that sheep may be a useful epidemiological
marker of P. brasiliensis presence in the environment and reinforce that contact with soil is an important risk factor for infection. 相似文献
32.
Zulpo DL Headley SA Biazzono L da Cunha IA Igarashi M de Barros LD Taroda A Cardim ST Bogado AL Navarro IT Garcia JL 《Experimental parasitology》2012,131(2):223-230
During this study, cats were immunized by the intranasal and rectal routes with crude rhoptry proteins of Toxoplasma gondii admixed with Quil-A. Twenty-five domestic short hair cats divided into five groups (n=5) were used during this evaluation: G1 and G3 cats received 200 μg of the rhoptry proteins with Quil-A (20 μg) by the intranasal and rectal routes, respectively; G2 and G4 cats received bovine serum albumin (BSA, 200 μg/dose) with Quil-A (20 μg); and G5 animals served as unvaccinated controls. All treatments were performed at days 0, 21, 42, and 63. The challenge was done with 800 cysts of the ME49 of T. gondii strain at day 70 (challenge day). The serum IgG, IgM, IgA, and fecal IgA antibody levels were evaluated by using the indirect enzyme-linked immunosorbent assay (ELISA). Some animals produced antibody levels beyond cut-off; however, two animals from G1 (OD(mean)=0.308, OD(cut-off)=0.200) and three from G3 (OD(mean)=0.254) demonstrated IgG levels on being challenged, with similar results occurring in two cats from G1 to IgM (OD(mean)=0.279, OD(cut-off)=0.200). Fecal IgA levels were detected in all G1 cats (OD(mean)=0.330, OD(cut-off)=0.065), and in one cat from G3 (OD(mean)=0.167). The serum and fecal humoral immune responses did not correlate with oocyst shedding. Oocyst shedding varied from 98.4% (G1), 87.5% (G2), 53.0% (G3), to 58% (G4), and was lower than that of G5 cats. The prepatent period of cats vaccinated intranasally (G1) was reduced from 6-9.6 to 2.8 days, suggesting protection of environmental contamination, considering cats as the primary source of contamination. The intranasally and rectally administered rhoptry vaccines were able to partially protect cats against T. gondii cysts on being challenged; however, the intranasal method of vaccination yielded better results relative to the rectal route. 相似文献
33.
Julio Beltrame Daleprane Vanessa da Silva Freitas Alejandro Pacheco Martina Rudnicki Luciane Aparecida Faine Felipe Augusto Dörr Masaharu Ikegaki Luis Antonio Salazar Thomas Prates Ong Dulcinéia Saes Parra Abdalla 《The Journal of nutritional biochemistry》2012,23(6):557-566
Propolis is a polyphenol-rich resinous substance extensively used to improve health and prevent diseases. The effects of polyphenols from different sources of propolis on atherosclerotic lesions and inflammatory and angiogenic factors were investigated in LDL receptor gene (LDLr?/?) knockout mice. The animals received a cholesterol-enriched diet to induce the initial atherosclerotic lesions (IALs) or advanced atherosclerotic lesions (AALs). The IAL or AAL animals were divided into three groups, each receiving polyphenols from either the green, red or brown propolis (250 mg/kg per day) by gavage. After 4 weeks of polyphenol treatment, the animals were sacrificed and their blood was collected for lipid profile analysis. The atheromatous lesions at the aortic root were also analyzed for gene expression of inflammatory and angiogenic factors by quantitative real-time polymerase chain reaction and immunohistochemistry. All three polyphenol extracts improved the lipid profile and decreased the atherosclerotic lesion area in IAL animals. However, only polyphenols from the red propolis induced favorable changes in the lipid profiles and reduced the lesion areas in AAL mice. In IAL groups, VCAM, MCP-1, FGF, PDGF, VEGF, PECAM and MMP-9 gene expression was down-regulated, while the metalloproteinase inhibitor TIMP-1 gene was up-regulated by all polyphenol extracts. In contrast, for advanced lesions, only the polyphenols from red propolis induced the down-regulation of CD36 and the up-regulation of HO-1 and TIMP-1 when compared to polyphenols from the other two types of propolis. In conclusion, polyphenols from propolis, particularly red propolis, are able to reduce atherosclerotic lesions through mechanisms including the modulation of inflammatory and angiogenic factors. 相似文献
34.
Adriana Ambrosini Anelise Beneduzi Thais Stefanski Felipe G. Pinheiro Luciano K. Vargas Luciane M. P. Passaglia 《Plant and Soil》2012,356(1-2):245-264
Background and Aims
This study was aimed at assessing the diversity of putatively diazotrophic rhizobacteria associated with sunflower (Helianthus annuus L.) cropped in the south of Brazil, and to examine key plant growth promotion (PGP) characteristics of the isolates for the purposes of increasing plant productivity.Methods
299 strains were isolated from the roots and rhizosphere of sunflower cultivated in five different areas using N-free media. 16S rDNA PCR-RFLP and 16S rRNA partial sequencing were used for identification and the Shannon index was used to evaluate bacterial diversity. Production of siderophores and indolic compounds (ICs), as well phosphate solubilization activities of each isolate were also evaluated in vitro. On the basis of multiple PGP activities, eight isolates were selected and tested for their N-fixation ability, and their capacity as potential PGPR on sunflower plants was also assessed.Results
All except three Gram-positive strains (phylum Actinobacteria) belonged to the Gram-negative Proteobacteria subgroups [Gamma (167), Beta (78), and Alpha (50)] and the family Flavobacteriaceae (1)]. Shannon indexes ranged from 0.96 to 2.13 between the five sampling sites. Enterobacter and Burkholderia were the predominant genera isolated from roots and rhizosphere, respectively. Producers of siderophores and ICs were widely found amongst the isolates, but only 19.8% of them solubilized phosphate. About 8% of the isolates exhibited all three PGP traits, and these mostly belonged to the genus Burkholderia. Four isolates were able to stimulate the growth of sunflower plants under gnotobiotic conditions.Conclusions
Enterobacter and Burkholderia were the dominant rhizospheric bacterial genera associated with sunflower plants. Inoculation with isolates belonging to the genera Achromobacter, Chryseobacterium, Azospirillum, and Burkholderia had a stimulatory effect on plant growth. 相似文献35.
Francisco Torres-Gonzalez Ariadne Runte-Geidel Claudio Antonioli Luciane C Wagner Dinarte Ballester Jose Miguel Caldas de Almeida Emiliano Galende Benjamín Vicente Miguel Xavier Manuel Gómez-Beneyto Michael B King Sandra M Saldivia 《Mental health in family medicine》2012,9(2):125-134
Background There is a lack of instruments to measure the needs, stigma and informal care of people with schizophrenia that take account of sociocultural variation and patients'' and formal and informal carers'' opinions and experiences.Aims To develop questionnaires to measure stigma, needs and informal (non-professional) care for people with schizophrenia.Method We undertook the study in seven countries and in English, Spanish and Portuguese. We first held focus group discussions with patients, formal carers (professionals) and informal carers (family and friends) in Spain, the UK, Argentina, Brazil, Chile and Venezuela to elicit the main dimensions of needs, stigma and informal care. We then held nominal group discussions about these dimensions with patients, family members and professionals in Spain, Portugal and the UK, to develop the instruments.Results Three hundred and three people participated in 46 focus groups and results were discussed in three nominal groups, each involving eight participants. Three instruments were developed in this iterative process: needs for care (46 items), stigma (38 items) and informal care (20 items).Conclusions These instruments are based on service users'' and carers'' views and experiences and have cross-cultural validity. They will have application in assessment of outcomes for people with schizophrenia and their families. 相似文献
36.
Thalita Vilaboim Santos Gualberto Ruas Luciane Aparecida Pascucci Sande de Souza Marcia Souza Volpe 《Journal of electromyography and kinesiology》2012,22(6):961-967
Breathing exercises (BE), incentive spirometry and positioning are considered treatment modalities to achieve lung re-expansion. This study evaluated the influence of incentive spirometry and forward leaning on inspired tidal volumes (VT) and electromyographic activity of inspiratory muscles during BE. Four modalities of exercises were investigated: deep breathing, spirometry using both flow and volume-oriented devices, and volume-oriented spirometry after modified verbal instruction. Twelve healthy subjects aged 22.7 ± 2.1 years were studied. Surface electromyography activity of diaphragm, external intercostals, sternocleidomastoid and scalenes was recorded. Comparisons among the three types of exercises, without considering spirometry after modified instruction, showed that electromyographic activity and VT were lower during volume-oriented spirometry (p = 0.000, p = 0.054, respectively). Forward leaning resulted in a lower VT when compared to upright sitting (p = 0.000), but electromyographic activity was not different (p = 0.606). Inspired VT and electromyographic activity were higher during volume-oriented spirometry performed after modified instruction when compared with the flow-oriented device (p = 0.027, p = 0.052, respectively). In conclusion BE using volume-oriented spirometry before modified instruction resulted in a lower work of breathing as a result of a lower VT and was not a consequence of the device type used. Forward leaning might not be assumed by healthy subjects during situations of augmented respiratory demand. 相似文献
37.
AP Bordon-Graciani LA Dias-Melicio MJ Acorci-Valério JP Araujo AM Soares 《Microbes and infection / Institut Pasteur》2012,14(12):1049-1053
In this study we investigated the role of nitric oxide (NO) in monocyte fungicidal activity against Paracoccidioides brasiliensis. We found that cells primed with IFN-γ, TNF-α or GM-CSF and challenged with a high-(Pb18) or low-virulence (Pb265) strain of the fungus increase their fungicidal activity. Expression of iNOS mRNA was increased after priming cells with each cytokine, and tended to be inhibited by Pb18. Despite up-regulation of iNOS mRNA expression by Pb265, an equivalent increase in NO production was not detected, as metabolite levels were similar in all cultures. The results indicated that high expression of human monocyte iNOS mRNA induced by P. brasiliensis is not correlated with NO concentrations produced. 相似文献
38.
Species of Canacidaesensu lato of Brazil are reviewed, including the subfamilies Canacinae and Tethininae. Included are seven species in five genera with two species, Nocticanace austra and Nocticanace packhamorum, from southern Brazil being newly described. To facilitate identification, we have included keys and diagnose to taxa at all levels. 相似文献
39.
Grando R Antônio MA Araújo CE Soares C Medeiros MA de Carvalho JE Lourenço AM Lopes LC 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(7-8):507-514
Triterpenoids with 31-norcycloartanone structure were isolated for the first time from the Solanum genus. Cycloeucalenone and 24-oxo-31-norcycloartanone were the main constituents of the dichloromethane extract of Solanum cernuum Vell. leaves [7% (w/w) and 1.47% (w/w)]. Both triterpenoids were tested against human tumour cell lines, and 24-oxo-31-norcycloartanone was significantly active and selective against the lung tumour cell line NCI-H460 with total growth inhibition at 1.10 microg/mL, growth inhibition 50 at 0.19 microg/mL and lethal concentration 50 at 8.43 microg/mL, while cycloeucalenone showed poor activity. A homologous series of alkanes (C25-C34), beta-sitosterol, and the xanthophyll lutein were also identified. The antiulcer activity was assayed for the dichloromethane extract. In the gastric ulcer model induced by 95% ethanol, administration of 500, 1000 and 2000 mg/kg/po dichloromethane extract gave ulcer lesion indices of, respectively, 38.2, 61.0 and 81.9%, while carbenoxolone inhibited 88.9% at 200 mg/kg. In the gastric ulcer model induced by indomethacin the dichloromethane extract showed a small percentage of lesion inhibition. The ethanol extract was also analyzed and was mainly composed of glycoalkaloids, peptides and disaccharides. 相似文献
40.
Regulation and Adaptive Evolution of Lactose Operon Expression in Lactobacillus delbrueckii 下载免费PDF全文
Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis are both used in the dairy industry as homofermentative lactic acid bacteria in the production of fermented milk products. After selective pressure for the fast fermentation of milk in the manufacture of yogurts, L. delbrueckii subsp. bulgaricus loses its ability to regulate lac operon expression. A series of mutations led to the constitutive expression of the lac genes. A complex of insertion sequence (IS) elements (ISL4 inside ISL5), inserted at the border of the lac promoter, induced the loss of the palindromic structure of one of the operators likely involved in the binding of regulatory factors. A lac repressor gene was discovered downstream of the beta-galactosidase gene of L. delbrueckii subsp. lactis and was shown to be inactivated by several mutations in L. delbrueckii subsp. bulgaricus. Regulatory mechanisms of the lac gene expression of L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis were compared by heterologous expression in Lactococcus lactis of the two lac promoters in front of a reporter gene (beta-glucuronidase) in the presence or absence of the lac repressor gene. Insertion of the complex of IS elements in the lac promoter of L. delbrueckii subsp. bulgaricus increased the promoter's activity but did not prevent repressor binding; rather, it increased the affinity of the repressor for the promoter. Inactivation of the lac repressor by mutations was then necessary to induce the constitutive expression of the lac genes in L. delbrueckii subsp. bulgaricus. 相似文献