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191.
Leishmaniases are endemic in many countries, mainly in rural areas. In Brazil, Leishmania infection is responsible for many cases of Leishmaniases, including recent reports in urban regions. Despite their sensitivity, traditional serological and parasitological methods for detecting Leishmaniases have proven inadequate for species discrimination. This study aimed to identify Leishmania species in biological samples by a fast methodology, avoiding "in vitro" cultivation. Knowledge of the Leishmania species is an important tool in regions where both New World visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are prevalent. As these new foci appear in areas not traditionally endemic for VL, the main problem is to distinguish between true autochthonous infections and infections acquired in other well-known endemic areas. Since, domestic dogs are known to be the main VL and CL reservoir, they are regularly investigated in endemic areas to prevent, principally, severe and often fatal VL in humans. However, several infected dogs present no clinical signs or clinical signs similar to other canine diseases. Here, we evaluated the ability of PCR to diagnose VL and distinguish L. (L.) chagasi from other Leishmania species in domestic dogs. Samples from 114 dogs from 30 cities (Sao Paulo, Brazil) were divided into two groups: 44 symptomatic and 70 asymptomatic. They were assayed by parasitological methods (culture and microscopic examination) and PCR to determine L. (L.) chagasi, L. (V.) braziliensis; and in some cases, Leishmania spp. Parasitological tests and PCR-L. chagasi were concordant in 105 samples (92%). VL was confirmed in 49 dogs, while 56 had negative results. Of the 114 samples, 9 had discordant results, but were further tested by PCR-Leishmania spp. with positive results. VL was also confirmed in 4 dogs having negative parasitological tests and positive PCR-L. chagasi. Consequently, this PCR was positive for 100% (53/49) of dogs with parasites detected in parasitological tests. Also, PCR demonstrated high specificity detecting 61 dogs negative for VL. Leishmania infection was negative in 56 dogs, and 5 with positive culture and PCR-Leishmania spp. had CL since they were positive in PCR-L. braziliensis. This study shows the importance of including PCR in diagnosis of Leishmaniases by differential diagnosis contributing to the surveillance and control of VL programs.  相似文献   
192.
Acupuncture has been shown to have the beneficial effect of reducing stress responses in animals and humans. Pharmacopuncture is the injection of subclinical doses of drugs into acupoints to give therapeutic results without side effects. This study compared the effects of injecting the usual dose of acepromazine (ACP; 0.1 mg/kg, intramuscularly [I.M.]) with those of pharmacopuncture (1/10 ACP dose at the governing vessel 1 [GV 1] acupoint) on the stress responses of healthy horses undergoing road transport for 2.5 hours. Four different treatments were applied immediately before loading, with 8 animals/treatment: injection of saline or ACP (0.1 mg/kg, I.M.) at the base of the neck; and injection of saline or 1/10 ACP (0.01 mg/kg) at the GV 1 acupoint. The road transport increased heart rate (HR), respiratory rate, body temperature, and serum cortisol of the untreated horses (injected with saline at the base of the neck). Pharmacopuncture at GV 1 reduced the average HR and transport-induced increase in HR at unloading, without changing the other variables. On the other hand, ACP (0.1 mg/kg) produced significant sedation and reduced the transport-induced increase in respiratory rate but without preventing the stress-induced increase of cortisol. Other acupuncture points and drugs should be tested to verify the beneficial effect of this therapy to reduce stress in horses during road transport.  相似文献   
193.
Growth performance of two Oreochromis niloticus strains, Chitralada and Red‐Stirling, their reciprocal crossbred and the Israeli tetra‐hybrid ND‐56 were assessed in net cages under on‐farming conditions. Throughout 268 days of grow‐out, the strains were weighed monthly and mortality, feed consumption and water quality were recorded. Ten rigid net cages (1.5 × 1.5 × 1.7 m) immersed in a 10 ha reservoir were linearly arranged near the reservoir outlet following a completely randomized design with two replicates for each treatment (strain). Each cage was stocked with 459 fish (120 fish m?3) and fed twice daily to apparent satiation with a commercial tilapia diet following the recommended feeding program. The final mean weights were higher for Chitralada (557.20 g) and the reciprocal crossbreds (522.95, 496.40 g) than those of Red‐Stirling (421.90 g). All treatments outperformed the ND‐56 tetra hybrid. Daily growth showed statistical differences between Chitralada (2.04 g) and Red‐Stirling (1.52 g) but they were statistically the same when compared with the reciprocal crossbreds (1.90, 1.80 g). The relative growth ratios showed the same trend observed in the results for daily growth. The mean survival rate was 98%. The overall growth rate showed that crossbred performed as well as the parental lines. All crossbred progeny presented red colouration with variable pattern of black marks corroborating the dominant inheritance of the red trait in Red‐Stirling strain.  相似文献   
194.
Long-term agricultural sustainability and water quality may be threatened by inadequate land management. Carbon (C) losses at the catchment scale largely depend on land use and management practices. In “Abelar” farm (A Coruña, NW Spain), swine slurry was directly discharged during a period of about 30 years onto agricultural maize fields and rangeland under cattle production. In 1998, the agricultural fields and rangeland were planted to stands of Eucalyptus globulus. The purpose of this work was to assess the concentrations and losses of total, inorganic, and organic carbon at the outlet of a small catchment (10.7 ha) in the period from March 2007 to December 2010. Nearly 190 water samples were collected; specifically eleven in 2007, sixty-eight in 2008, fifty-six in 2009, and fifty-three in 2010. Total runoff volumes from the catchment were also measured during the 3.7-year study period. Except for a peak recorded in November 2008, total carbon values (TC) ranged from 1.51 to 6.14 mg L?1, total inorganic carbon (TIC) varied between 0.54 and 3.30 mg L?1, and total organic carbon (TOC) was between 0.38 and 2.83 mg L?1; the exception was due to an occasional pig slurry discharge occurring in 2008, which drove the greatest values of the three carbon forms. The season of the year influenced concentrations of total, organic, and inorganic carbon. Total, organic, and inorganic carbon loads exported at the catchment outlet were estimated at the monthly and yearly time scales. Overall, 10 years after planting to the forest, dissolved and total carbon losses were rather small.  相似文献   
195.
European Journal of Plant Pathology - The fungus Colletotrichum lindemuthianum has genes that encode different enzymes involved in plant cell wall degradation such as pectinases, which are...  相似文献   
196.
Ascidians of the genus Aplidium are recognized as an important source of chemical diversity and bioactive natural products. Among the compounds produced by this genus are non-nitrogenous metabolites, mainly prenylated quinones and hydroquinones. This review discusses the isolation, structural elucidation, and biological activities of quinones, hydroquinones, rossinones, longithorones, longithorols, floresolides, scabellones, conicaquinones, aplidinones, thiaplidiaquinones, and conithiaquinones. A compilation of the 13C-NMR spectral data of these compounds is also presented.  相似文献   
197.
Trichoderma spp. are used as antagonists against different pathogens. Despite many possibilities of using Trichoderma as an antagonist, there are gaps in the knowledge of the interaction between Trichoderma, cassava and Scytalidium lignicola. This fungus causes cassava black root rot and is an inhabitant of the soil, so it is difficult to control. Antagonists may contribute to the possible induction of resistance of plants because, when exposed to such pathosystems, plants respond by producing antioxidative enzymes. The test for potential inhibition of growth of S. lignicola CMM 1098 in vitro was performed in potato-dextrose-agar with two Trichoderma strains T. harzianum URM3086 and T. aureoviride URM 5158. We evaluated the effect of the two selected Trichoderma to reduce the severity of cassava black root rot and shoots. Subsequently, the production of enzymes (ascorbate peroxidase, catalase, peroxidase and polyphenol oxidase) was evaluated in cassava plants. All two Trichoderma strains show an inhibition of the growth of S. lignicola CMM 1098. The most efficient was T. harzianum URM 3086, with 80.78% of mycelial growth inhibition. T. aureoviride URM 5158 was considered the best chitinase producer. All treatments were effective in reducing severity, especially treatments using Trichoderma. Cassava plants treated with T. aureoviride URM 5158 had the highest enzyme activity, especially peroxidase and ascorbate peroxidase. Trichoderma harzianum URM3086 and Trichoderma aureoviride URM 5158 were effective in reducing the severity of cassava black root rot caused by S. lignicola CMM 1098.  相似文献   
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