Leguminous trees from tropical dry forest generate fertility islands in pastures     

María de la Luz Avendaño-Yáñez  Yareni Perroni  Sergio Pérez-Elizalde 《Arid Land Research and Management》2018,32(1):57-70

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The effects of osmolality on sperm quality in <Emphasis Type="Italic">Jenynsia multidentata</Emphasis> (Cyprinodontiformes: Anablepidae)     

Janaína?Camacho?da?Silva  Antonio?Sergio?Varela Junior  J?sie?Shwartz?Caldas  Clarissa?da?Silva Freitas  Joziel?Gon?alves?Botelho  Elton?Pinto?Colares  Carine?Dahl?CorciniEmail authorView author&#;s OrcID profile 《Fish physiology and biochemistry》2016,42(1):93-102

Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters.  相似文献   

Systemic acquired resistance activation in solanaceous crops as a management strategy against root‐knot nematodes          下载免费PDF全文

Sergio Molinari 《Pest management science》2016,72(5):888-896

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Changes in Bacterial Populations During Bioremediation of Soil Contaminated with Petroleum Hydrocarbons     

Sergio Cisneros de la Cueva  César Hernández Rodríguez  Nicolás Oscar Soto Cruz  Juan Antonio Rojas Contreras  Javier López Miranda 《Water, air, and soil pollution》2016,227(3):91

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Degradation of Hexachlorocyclohexanes (HCHs) by Stable Zero Valent Iron (ZVI) Microparticles     

Carmen M. Dominguez  Sergio Rodriguez  David Lorenzo  Arturo Romero  Aurora Santos 《Water, air, and soil pollution》2016,227(12):446

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Phosphorus fractions in Brazilian Cerrado soils as affected by tillage   总被引：3，自引：0，他引：3  

Paulo Sergio Pavinato  Alexandre Merlin  Ciro Antonio Rosolem   《Soil & Tillage Research》2009,105(1):149-155

No-tillage systems lead to physical, chemical and biological changes in soil. Soil fertility is responsive to changes in tillage as it depends on nutrient status, soil water content and biological characteristics. This work aimed to determine long term changes in phosphorus forms and availability in the profile of two tropical soils under conventional and no-till systems, and to discuss the significance of these changes on plant growth and demand for P fertilizers. Undisturbed soil cores with 20 cm in diameter were collected to a depth of 40 cm, accommodated in PVC tubes and taken to a greenhouse, where the experiment was conducted. Two soils were collected in Central Brazil, in areas under Cerrado. Both soils had been cropped for at least 10 years under conventional tillage and no-till. In the greenhouse, pots received phosphorus fertilization or not at 43.7 kg ha⁻¹, and soybean was grown for 60 days, when soil P fractions were determined. Labile P fractions in the soil profile were not affected by management systems, and there was no accumulation of available P under no-till. A large amount of P added as fertilizer was adsorbed in soil and remained in moderately labile fractions, mainly on uppermost soil layers. Therefore, the phosphate fertilizer has promoted P accumulation on less available fractions in soil, remaining P on the soil after crop harvest. Eventually this phosphorus could migrate to more labile fractions and be available for crops grown in succession.  相似文献   

Effect of paratuberculosis on the diagnosis of bovine tuberculosis in a cattle herd with a mixed infection using interferon-gamma detection assay     

Alvarez J  de Juan L  Bezos J  Romero B  Sáez JL  Marqués S  Domínguez C  Mínguez O  Fernández-Mardomingo B  Mateos A  Domínguez L  Aranaz A 《Veterinary microbiology》2009,135(3-4):389-393

Interferon-gamma (IFN-gamma) detection assay is being applied as an ancillary test to tuberculin tests in the diagnosis of bovine tuberculosis to detect the maximum number of infected animals. Among possible factors influencing the performance of tuberculosis-diagnostic tests, paratuberculosis, a widespread disease in Spain and other European countries, has been pointed out as a cause of false positive reactions. Still, its effect on the sensitivity of these tests in cattle has yet to be fully characterized. The impact of paratuberculosis in the apparent sensitivity of IFN-gamma assay was studied in a bullfighting cattle herd with a mixed tuberculosis-paratuberculosis infection, using culture of Mycobacterium bovis and Mycobacterium avium paratuberculosis as the gold standard to determine the infection status of every animal. A total of 218 animals were slaughtered and sampled for bacteriology after blood sampling. IFN-gamma assay showed a lower apparent sensitivity in animals with a mixed infection (50%) compared to all animals suffering tuberculosis (78.3%). This finding indicates that the presence of paratuberculosis in tuberculosis-infected herds could imply a serious impairment in the sensitivity of IFN-gamma detection test.  相似文献   

Identification of CD3+ T lymphocytes in the green turtle Chelonia mydas     

Fernando A. Muoz  Sergio Estrada-Parra  Andres Romero-Rojas  Thierry M. Work  Erik Gonzalez-Ballesteros  Iris Estrada-Garcia 《Veterinary immunology and immunopathology》2009,131(3-4):211-217

To understand the role of the immune system with respect to disease in reptiles, there is the need to develop tools to assess the host's immune response. An important tool is the development of molecular markers to identify immune cells, and these are limited for reptiles. We developed a technique for the cryopreservation of peripheral blood mononuclear cells and showed that a commercially available anti-CD3 epsilon chain antibody detects a subpopulation of CD3 positive peripheral blood lymphocytes in the marine turtle Chelonia mydas. In the thymus and in skin inoculated with phytohemagglutinin, the same antibody showed the classical staining pattern observed in mammals and birds. For Western blot, the anti-CD3 antibodies identified a 17.6 kDa band in membrane proteins of peripheral blood mononuclear cell compatible in weight to previously described CD3 molecules. This is the first demostration of CD3+ cells in reptiles using specific antibodies.  相似文献   

Genetic immunization with the immunodominant antigen P48 of Mycoplasma agalactiae stimulates a mixed adaptive immune response in BALBc mice     

Bernardo Chessa  Marco Pittau  Maria Puricelli  Rosanna Zobba  Elisabetta Coradduzza  Paola Dall&#x;Ara  Sergio Rosati  Giorgio Poli  Alberto Alberti 《Research in veterinary science》2009,86(3):414-420

A DNA vaccine against contagious agalactia was developed for the first time, encoding the P48 of Mycoplasma agalactiae. Specific immune responses elicited in BALB/c mice were evaluated. Both total IgG and IgG1 were detected in mice vaccinated with pVAX1/P48. Proliferation of mononuclear cells of the spleen, levels of gamma interferon, interleukin-12, and interleukin-2 mRNAs were enhanced in immunized animals. Results indicate that pVAX1/P48 vaccination induced both T_h1 and T_h2 immune responses. Nucleic acid immunization could be a new strategy against M. agalactiae infections and may be potentially used to develop vaccines for other Mycoplasma diseases.  相似文献   

Chemopreventive Effects of Free and Bound Phenolics Associated to Steep Waters (Nejayote) Obtained After Nixtamalization of Different Maize Types     

Rojas-García C  García-Lara S  Serna-Saldivar SO  Gutiérrez-Uribe JA 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):94-99

Free and bound phenolics extracts from nejayote solids were obtained after optimally lime-cooking blue, normal white, red, normal yellow, high-carotenoid and quality protein maize types. The extraction yield ranged from 4.47 to 10.05%. Bound phenolics extracts had higher content of total phenolics, antioxidant activity and ferulic acid compared to the free phenolics extracts. In general, free phenolics extracts were less cytotoxic than the bound phenolics counterparts. Bound phenolics extracts had higher induction of quinone reductase (QR) and particularly the normal yellow nejayote exerted the highest chemopreventive index tested in Hepa1c1c7 cells. When tested for monofunctional phase 2 induction capacity in BPrc1 cells, the bound phenolics extracts of blue, normal white and quality protein nejayotes were better inducers than the normal yellow counterpart. Particularly, the free phenolics extract of the white maize nejayote induced BPrc1 cells QR and exerted a higher chemopreventive index compared to the bound phenolics extract. Therefore, the nejayote of the normal white maize was the best source of monofunctional phase 2 enzyme inducers.  相似文献