Effects of polymerization changes in maize proteins during nixtamalization on the thermal and viscoelastic properties of masa in model systems     

Adriana Quintanar Guzmán  María Eugenia Jaramillo Flores  Javier Solorza Feria  María Guadalupe Méndez Montealvo  Ya-Jane Wang 《Journal of Cereal Science》2010

Although nixtamalization is widely used in the food industry, a comprehensive understanding of the influence of proteins on the viscoelastic behavior and thermal properties in masa is still lacking. In this work, the effect of protein changes and its influence on the masa viscoelastic behavior were studied using model systems. Mixtures of lime-starch, zein-starch and lime-zein-starch were cooked at 90 °C from 20 to 150 min. Zein changes during cooking were analyzed by SDS-PAGE. Thermal transition temperatures and enthalpies were determined using differential scanning calorimetry (DSC). Dynamic oscillatory tests were undertaken on model system samples with 50% (w/v) moisture content, using a strain-controlled rheometer. SDS-PAGE showed that zein polymerizes during cooking. In the zein-starch model system, no visible protein bands were found after 30 min cooking; however, when lime was present, five bands were observed in all samples. Thermal transitions were observed around 55–62 °C for all model systems, probably corresponding to starch retrogradation. Rheological studies showed that protein exhibited higher influence in the gel strength by increasing the elastic character of the system. It was hypothesized that the combined effects of lime on starch, zein polymerization and the formation of calcium-zein bonds during cooking, yield a stronger and more elastic gel structure.  相似文献   

Probiotic preparation reduces the faecal water genotoxicity in chickens fed with aflatoxin B1 contaminated fodder     

Katarzyna Slizewska  Adriana Nowak  Zdzislawa Libudzisz  Janusz Blasiak 《Research in veterinary science》2010,89(3):391-395

The aim of the study was to evaluate the influence of a probiotic preparation on the genotoxicity of faecal water of broiler chickens fed with a fodder contaminated with aflatoxin B₁ (AFB₁) at 1 or 5 mg per kg. Human blood lymphocytes were exposed to chicken’s faecal water samples and DNA damage was measured using the comet assay. Genotoxicity of faecal water did not depend on the AFB₁ concentration in the fodder. The mean DNA damage, measured as the percentage of DNA in the tail of the comets, for chickens fed with fodder with AFB₁ at 1 mg/kg was 16.80 ± 0.66, at 5 mg/kg – 16.73 ± 1.51 and in the controls – 12.79 ± 0.66. The supplementation of fodder with the probiotic preparation decreased the extent of DNA damage to 10.02 ± 0.39 for 1 mg/kg AFB₁ and to 11.89 ± 0.72 for 5 mg/kg.  相似文献   

Signatures of adaptation to obligate biotrophy in the Hyaloperonospora arabidopsidis genome   总被引：2，自引：0，他引：2  

Baxter L  Tripathy S  Ishaque N  Boot N  Cabral A  Kemen E  Thines M  Ah-Fong A  Anderson R  Badejoko W  Bittner-Eddy P  Boore JL  Chibucos MC  Coates M  Dehal P  Delehaunty K  Dong S  Downton P  Dumas B  Fabro G  Fronick C  Fuerstenberg SI  Fulton L  Gaulin E  Govers F  Hughes L  Humphray S  Jiang RH  Judelson H  Kamoun S  Kyung K  Meijer H  Minx P  Morris P  Nelson J  Phuntumart V  Qutob D  Rehmany A  Rougon-Cardoso A  Ryden P  Torto-Alalibo T  Studholme D  Wang Y  Win J  Wood J  Clifton SW  Rogers J  Van den Ackerveken G  Jones JD 《Science (New York, N.Y.)》2010,330(6010):1549-1551

Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy.  相似文献   

Feline immunodeficiency virus,feline leukemia virus and Bartonella species in stray cats on St Kitts,West Indies     

Patrick J. Kelly  Lenita Moura  Tanya Miller  Jaime Thurk  Nicole Perreault  Adriana Weil  Ricardo Maggio  Helene Lucas  Edward Breitschwerdt 《Journal of Feline Medicine and Surgery》2010,12(6):447-450

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Differential display and suppression subtractive hybridization analysis of the pulp of ripening banana     

Adriana de Godoy  Beatriz Rosana CordenunsiFranco Maria Lajolo  João Roberto Oliveira do Nascimento 《Scientia Horticulturae》2010

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Molecular sequence data of Thecaphora frezii affecting peanut crops in Argentina     

Cinthia Conforto  Ignacio Cazón  Franco D. Fernández  Adriana Marinelli  Claudio Oddino  Alejandro M. Rago 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(4):663-666

In Argentina, Thecaphora frezii is the causal agent of peanut smut, causing severe yield losses in peanut growing areas. In this work sequence data of the large ribosomal subunit (28S rDNA) of four T. frezii specimens from different production regions are provided. A fragment of about 650 bp was amplified by PCR from each of the isolates analyzed. The analysis of the sequences demonstrated 100 % identity among the four specimens and 92–96.3 % identity with sequences of other species of Thecaphora. This is the first study on molecular sequences of this pathogen.  相似文献   

The relative impact of forest patch and landscape attributes on black howler monkey populations in the fragmented Lacandona rainforest, Mexico     

Víctor Arroyo-Rodríguez  Iraida M. González-Perez  Adriana Garmendia  Mireia Solà  Alejandro Estrada 《Landscape Ecology》2013,28(9):1717-1727

Land-use change is forcing many animal populations to inhabit forest patches in which different processes can threaten their survival. Some threatening processes are mainly related to forest patch characteristics, but others depend principally on the landscape spatial context. Thus, the impact of both patch and landscape spatial attributes needs to be assessed to have a better understanding of the habitat spatial attributes that constraint the maintenance of populations in fragmented landscapes. Here, we evaluated the relative effect of three patch-scale (i.e., patch size, shape, and isolation) and five landscape-scale metrics (i.e., forest cover, fragmentation, edge density, mean inter-patch isolation distance, and matrix permeability) on population composition and structure of black howler monkeys (Alouatta pigra) in the Lacandona rainforest, Mexico. We measured the landscape-scale metrics at two spatial scales: within 100 and 500 ha landscapes. Our findings revealed that howler monkeys were more strongly affected by local-scale metrics. Smaller and more isolated forest patches showed a lower number of individuals but at higher densities. Population density also tended to be positively associated to matrices with higher proportion of secondary forests and arboreal crops (i.e. with greater permeability), most probably because these matrices can offer supplementary foods. The immature-to-female ratio also increased with matrix permeability, shape complexity, and edge density; habitat characteristics that can increase landscape connectivity and sources availability. The prevention of habitat loss and isolation, and the increment of matrix permeability are therefore needed for the conservation of this endangered Neotropical mammal.  相似文献   

Immune-endocrine interactions in treated and untreated cats naturally infected with FIV     

Gómez NV  Castillo VA  Gisbert MA  Pisano P  Mira G  Fontanals A  Blatter MF 《Veterinary immunology and immunopathology》2011,143(3-4):332-337

Feline immunodeficiency virus (FIV) is a lentivirus that causes a progressive disruption of immune function in cats. The neuroendocrine and immune systems communicate bidirectionally, mediated by cytokines such as tumour necrosis factor-α (TNF), several interleukins (IL-1, IL-6, IL-10), and through signals induced by the ratio of IL-10 to IL-12. FIV can affect both pituitary adrenal and thyroid axis function. Twenty FIV-infected cats in similar stages of the disease were evaluated for six months. A cross-sectional study in which the twenty cats were divided into two groups was performed. Ten were treated with Zidovudine (ZDV: 5mg/kg/d, PO, q12h, for six months) and 10 were untreated. Plasma concentrations of adrenocorticotropic hormone (ACTH), cortisol, T4, FT4, T3, IL-10, IL-12 and viral load (VL) were evaluated after six months. ACTH was found in significantly lower concentrations (p<0.0001) in the treated group whereas cortisol did not show significant differences between the two groups. Both T4 and FT4 had high values in untreated individuals (p<0.001) compared with Zidovudine treated cats. T3 did not show significant differences between the two groups. Both IL-10 and IL-12 were found in significantly higher concentrations in ZDV treated cats (p<0.001). By contrast, the IL10/IL-12 ratio values were significantly lower in untreated cats. Viral load was significantly lower in the treated cats after six months of therapy, compared with values detected pre-treatment (p<0.002). Untreated cats showed a significant increase of VL (p<0.04) compared with the values at the beginning of the study. In treated cats, VL showed lower numbers of viral copies than in untreated cats (p<0.01). In summary, Zidovudine treatment appeared to contribute to the normalization of both the adrenal and thyroid axes. This effect could be attributed to the decrease observed in VL, resulting in a change in cytokine patterns.  相似文献   

Application of factorial designs to study factors involved in the determination of aldehydes present in beer by on-fiber derivatization in combination with gas chromatography and mass spectrometry     

Carrillo G  Bravo A  Zufall C 《Journal of agricultural and food chemistry》2011,59(9):4403-4411

With the aim of studying the factors involved in on-fiber derivatization of Strecker aldehydes, furfural, and (E)-2-nonenal with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine in beer, factorial designs were applied. The effect of the temperature, time, and NaCl addition on the analytes' derivatization/extraction efficiency was studied through a factorial 2(3) randomized-block design; all of the factors and their interactions were significant at the 95% confidence level for most of the analytes. The effect of temperature and its interactions separated the analytes in two groups. However, a single sampling condition was selected that optimized response for most aldehydes. The resulting method, combining on-fiber derivatization with gas chromatography-mass spectrometry, was validated. Limits of detections were between 0.015 and 1.60 μg/L, and relative standard deviations were between 1.1 and 12.2%. The efficacy of the internal standardization method was confirmed by recovery percentage (73-117%). The method was applied to the determination of aldehydes in fresh beer and after storage at 28 °C.  相似文献   

Prevalence of seizures in dogs and cats with idiopathic internal hydrocephalus and seizure prevalence after implantation of a ventriculo-peritoneal shunt     

Daniela Farke  Malgorzata Kolecka  Adriana Czerwik  Marcin Wrzosek  Sebastian Schaub  Martin Kramer  Klaus Failing  Martin Jürgen Schmidt 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1986-1992

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