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Almeida MA Jesus EE Sousa-Atta ML Alves LC Berne ME Atta AM 《Veterinary immunology and immunopathology》2005,106(1-2):151-158
Visceral leishmaniasis (VL) presents vigorous Th2 immune response, which is mainly characterized in human by augmented expression of Il-4, polyclonal B cell activation, intense hypergammaglobulinemia and production of antileishmanial IgE antibodies. However, few aspects of this type of immune response have been demonstrated in studies of canine visceral leishmaniasis (CVL). This work investigated by ELISA and western immunoblotting the production of antileishmanial IgE antibodies (IgE Ab) in symptomatic and asymptomatic dogs naturally infected by Leishmania chagasi, and also compared this IgE immune response with those of IgG, IgG1 and IgG2 antibodies. Three groups of dogs were evaluated: 12 VL dogs with positive Leishmania biopsies (GI), 44 dogs with a positive leishmanial indirect fluorescent antibody test (IFAT), 30 of them presenting clinical signs of VL and 14 asymptomatic (GII) and 21 healthy dogs living in kennels located in leishmaniasis endemic areas (GIII), which were seronegative in the IFAT. Eighteen dogs from an area free of CVL were used as controls (GIV). Antileishmanial IgE antibodies were detected in 4 of 12 VL dogs from group I (33%) and 14 of 30 symptomatic dogs from group II (47%). While all asymptomatic dogs from group II (100%) were seronegative for antileishmanial IgE Ab, 7 of 21 healthy animals from group III (33%) had these immunoglobulins. A strong correlation was verified between antileishmanial IgG and IgG2 antibody titers in all symptomatic dogs, but only 15 of these 42 animals (36%) produced simultaneously IgE, IgG, IgG1 and IgG2 antibodies to Leishmania. IgE antibodies recognized leishmanial antigens of 12, 36, 61, 81 and 118 KDD, while a more complex pattern of immunoblotting was verified mainly for IgG and IgG2 antibodies from symptomatic animals. IgG1 and IgG2 antibodies shared the recognition of L. chagasi polypeptides of 118, 81, 61, 36, 18, 14 and 12 KDD, being more intense the immune reactions between IgG1 Ab and the leishmanial polypeptides of 61 and 36 KDD, and also between IgG2 antibodies and the antigens of 26, 21, 18, 14 and 12 KDD. Our results suggest that the polyclonal production of antileishmanial antibodies that includes IgE Ab could characterize a Th2 immune response in CVL and can help the laboratory diagnosis of this disease. 相似文献
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Almeida MA Jesus EE Sousa-Atta ML Alves LC Berne ME Atta AM 《Veterinary parasitology》2005,127(3-4):227-232
Human visceral leishmaniasis is endemic in the northeast of Brazil, where the domestic dog is an important parasite reservoir in the infectious cycle of Leishmania chagasi. In this study, we evaluated the clinical signs of canine visceral leishmaniasis (CVL), serum protein profile and the antileishmanial IgG antibody production in 86 dogs living in northeast endemic areas of leishmaniasis. Thirty dogs from a leishmaniasis-free area were used as a control group. The major clinical signs of CVL seen were emaciation and skin ulcers (80%), followed by onychogryphosis and conjunctivitis (73%). Depilation was observed in 60% of animals while lymphadenomegaly, splenomegaly, liver enlargement or kidney involvement was less frequent (< or =20%). VL seropositive dogs presented with serum hyperproteinemia, hypoalbuminemia, hypergammaglobulinemia and decreased albumin/globulin ratio. A lower sensitivity and higher specificity was observed for promastigote indirect fluorescent antibody test (IFAT) (83 and 100%, respectively) compared with enzyme-linked immunosorbent assay (ELISA) (94 and 90%), which uses a crude extract of Leishmania. There was a positive correlation between IFAT and ELISA titers of antileishmanial IgG antibodies (Spearman test, P < 0.05), which was augmented in CVL dogs. This study found that the determination of serum protein, A/G ratio and the use of two different leishmanial serological tests like IFAT and ELISA are essential in CVL screening. 相似文献
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Chickpea （Cicer arietinum L.）, is an important grain legume crop throughout the world especially in developing countries. However the average yield worldwide is considered to be lower than its potential yield （Singh et al., 1994）. The average yield of chickpea is much lower in Pakistan, which is about 5500-650 kg/hm^2 due to various abiotic and biotic stresses （Shah et al., 2005）. 相似文献
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The disposition kinetics of tylosin was studied in goats after intravenous (i.v.) or intramuscular (i.m.) injection of 15 mg/kg body wt. Following i.v. injection, tylosin was rapidly and widely distributed with a distribution half-life of 0.2 h and volume of distribution of 1.7 l/kg. It was slowly eliminated with a mean elimination half-life of 3.04 h and a total body clearance rate of 6.8 ml/kg/min. Following i.m. injection, tylosin was slowly absorbed (tau 1/2 ab of 1.82 h). Tylosin concentration in serum was greater than 1 microgram/ml after 1 h and persisted up to 12 h post-injection. The peak concentration (Cmax 2.38 micrograms/ml) was obtained after 4.19 h. The systemic bioavailability of tylosin injected intramuscularly was 72.6% and the serum protein bound fraction was 37.59% of the total drug. Tylosin was excreted in milk and urine at concentrations much higher than that in serum. Low concentrations of tylosin were reported in ruminal juice of goats. In conclusion tylosin should be injected every 14 h to obtain an appreciable concentration in serum, milk and urine. 相似文献
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Ullah Atta Akram Zahid Malik Saad Imran Khan Khalid Saif Ullah 《Genetic Resources and Crop Evolution》2021,68(7):2827-2847
Genetic Resources and Crop Evolution - Soybean is a high-nutritional crop that provides a sustainable source of dietary protein and edible oil for human consumption and animal diet. In this... 相似文献
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Atta Akbari Omid Moini Jazani Mohammad Reza Saeb Kobra Pourabdollah Fariba Soltanolkottabi 《Fibers and Polymers》2014,15(6):1230-1235
A proper collector is designed and examined in electrospinning process to produce electrospun nanofibers with favored mechanical propertied. The quality of product was controlled by changing and optimizing the process variables, namely electrospinning time, gap distance, and collector rotating speed in a manner that well-aligned yarns were fabricated from polyacrylonitrile (PAN) dilute solutions. It was found that the tensile characteristics of fabricated yarns are greatly dependent on the process variables. Incorporation of multi-walled carbon nanotubes (MWCNTs) into the polymer solution revealed improvement to the yarn strength because of enhancement in alignment of the filaments. The state of fiber alignment and dispersion of MWCNTs were detected by means of scanning electron microscopy. It was illustrated that combination of nanofibers and microfibers gives PAN/MWCNTs composite nanofibers with high surface area and high porosity to satisfy sophisticated users. 相似文献
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Silong ZHAI Junjie XIE Zongyi TONG Bing YANG Weiping CHEN Roger T. KOIDE Yali MENG Xiaomin HUANG Atta Mohi Ud DIN Changqing CHEN Haishui YANG 《土壤圈》2024,34(2):339-350
Straw return is a sustainable soil fertility-building practice, which can affect soil microbial communities. However, how straw return affects arbuscular mycorrhizal fungi (AMF) is not well explored. Here, we studied the impacts of different straw management treatments over eight years on the structure and functioning of AMF communities in a rice-wheat rotation system. The straw management treatments included no tillage with no straw (NTNS), rotary tillage straw return (RTSR), and ditch-buried straw return (DBSR). The community structure of AMF was characterized using high-throughput sequencing, and the mycorrhizal functioning was quantified using an in situ mycorrhizal-suppression treatment. Different straw management treatments formed unique AMF community structure, which was closely related to changes in soil total organic carbon, available phosphorus, total nitrogen, ammonium, and nitrate. When compared with NTNS, RTSR significantly increased Shannon diversity in 0-10 cm soil layer, while DBSR increased it in 10-20 cm soil layer; DBSR significantly increased hyphal length density in the whole ploughing layer (0-20 cm), but RTSR only increased it in the subsurface soil layer (10-20 cm). The mycorrhizal responses of shoot biomass and nutrient (N and P) uptake were positive under both straw return treatments (RTSR and DBSR), but negative under NTNS. The community composition of AMF was significantly correlated to hyphal length density, and the latter was further a positive predictor for the mycorrhizal responses of plant growth and nutrient uptake. These findings suggest that straw return can affect AMF community structure and functioning, and farmers should manage mycorrhizas to strengthen their beneficial effects on crop production. 相似文献
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A gene that confers double-podding in chickpea is considered to be important for breeding higher yielding cultivars. Double-podded mutants were produced from five desi- and four kabuli-type chickpea genotypes through induced mutations and stabilty was checked up to M13 generation. Desi-type produced higher number of mutants as compared with kabuli-type. The inheritance studies in induced mutants of six genotypes showed that the double-podded trait was governed by single recessive gene. Different genotypes and their double-podded mutants were also characterized through sequence-tagged microsatellite site marker, TA-80. Allelic variations were found in single-podded genotypes and eight different alleles were identified, while for double-poddedness no allelic variants were found in all the analysed mutants. Addition of bases in the double-podded mutants showed that there might be involvement of transposable elements in the production of double-podded mutants through mutagens. 相似文献