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171.
Luppi MM Luiz AP Coelho FM Malta Mde C Preis IS Ecco R da Fonseca FG Resende M 《Veterinary microbiology》2011,154(1-2):69-77
Psittacid herpesvirus (PsHV) was isolated from 41 birds kept in captivity in Belo Horizonte, Minas Gerais/Brazil using chicken embryo fibroblasts (CEF) cell cultures. For this study, leukocytes or cloacal swabs of live birds were used. Also, portions of liver, spleen or kidney from birds collected at necropsy were utilized for these tests. PCR tests confirmed the presence of PsHV in 100% of samples. Thirty-three of the PCR products were sequenced and the results disclosed a 99% and 100% identity when compared with other sequences PsHV-1 (AY372243.1 and AF261756.1), previously deposited in GenBank. In addition, histopathology was performed and 19 of the 29 birds contained random multifocal lymphoplasmacytic hepatitis with necrotic foci, suggestive of viral infection. Three samples were examined by electron microscopy to visualize the viral particles obtained from cell culture. The viral structures measured 269 nm in average, had envelopes with an icosahedral capsid and tegument, consistent with herpesvirus. Thus, a total of 41 isolates were obtained from PsHV cell cultivation in CEF, confirming the circulation of the virus between parrots kept in captivity in Belo Horizonte, and affirming the importance of further studies in this area. 相似文献
172.
Rocha TS Cunha VA Jane JL Franco CM 《Journal of agricultural and food chemistry》2011,59(8):4208-4216
Structural characteristics of native and annealed Peruvian carrot (Arracacia xanthorrhiza) starches were determined and compared to those of cassava and potato starches. Peruvian carrot starch presented round and irregular shaped granules, low amylose content and B-type X-ray pattern. Amylopectin of this starch contained a large proportion of long (DP > 37) and short (DP 6-12) branched chains. These last ones may contribute to its low gelatinization temperature. After annealing, the gelatinization temperatures of all starches increased, but the ΔH and the crystallinity increased only in Peruvian carrot and potato starches. The annealing process promoted a higher exposure of Peruvian carrot amylose molecules, which were more quickly attacked by enzymes, whereas amylopectin molecules became more resistant to hydrolysis. Peruvian carrot starch had structural characteristics that differed from those of cassava and potato starches. Annealing affected the semicrystalline structure of this starch, enhancing its crystallinity, mainly due to a better interaction between amylopectin chains. 相似文献
173.
Quinchia LA Delgado MA Valencia C Franco JM Gallegos C 《Journal of agricultural and food chemistry》2011,59(24):12917-12924
Knowledge of the oxidative stability of vegetable oils for lubricant applications is a key point, because vegetable oil oxidation potential is the main disadvantage for its use as a lubricant. Oil degradation after an oxidation process can seriously affect its lubricating function and increase wear. In this work, two different methods for evaluating the oxidation stability of lubricating vegetable oils, the oxidation onset temperature, characterized through DSC measurements (ASTM E 2009-08), and the pressure drop in the oxygen pressure vessel (ASTM D 942-02), have been used. Additionally, thermogravimetric analysis and FTIR studies have also been carried out. High-oleic sunflower (HOSO) and castor (CO) oils were selected and blended with natural ((+)-α-tocopherol (TCP), propyl gallate (PG), l-ascorbic acid 6-palmitate (AP)) or synthetic antioxidants (4,4'-methylenebis(2,6-di-tert-butylphenol) (MBP)), with the aim of formulating biodegradable vegetable-based lubricants according to REACH regulation. (1) The results showed that the most effective biodegradable antioxidant is PG, comparable to MBP, whereas lower effectiveness was obtained for TCP and AP. In relation to the methods tested, DSC measurements achieve accurate data more quickly for evaluating the oxidation stability of these basestocks, showing a linear correlation with the traditional method based on the oxygen bomb test. The empirical equation obtained depends on the mechanism involved in the antioxidant activity. 相似文献
174.
Silvia Franco Andrade Daniel Silva Kupper Luiz Fernando Rodrigues de Pinho Elizabeth Cunha Franco Marcus Vin��cius Felix Fabri Prataviera Rodrigo Rolim Duarte Jos�� Ricardo Cec��lio Junqueira 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(2):171-176
The objective of this study was to evaluate and validate the accuracy of the Perkins handheld applanation tonometer for measuring intraocular pressure (IOP) in horses and cattle. Both eyes of 10 adult horses and cattle were evaluated in a postmortem study. The eyes from 10 clinically normal adult horses and cattle were also examined after bilateral auriculopalpebral nerve block and topical anesthesia for an in vivo study. IOP was measured postmortem using direct manometry (measured with an aneroid manometer) and tonometry (measured with a Perkins handheld applanation tonometer). The correlation coefficients (r2) for the data from the postmortem manometry and Perkins tonometer study were 0.866 for horses and 0.864 for cattle. In the in vivo study, IOP in horses was 25.1 ± 2.9 mmHg (range 19.0~30.0 mmHg) as measured by manometry and 23.4 ± 3.2 mmHg (range 18.6~28.4 mmHg) according to tonometry. In cattle, IOP was found to be 19.7 ± 1.2 mmHg (range 18.0~22.0 mmHg) by manometry and 18.8 ± 1.7 mmHg (range 15.9~20.8 mmHg) by tonometry. There was a strong correlation between the IOP values obtained by direct ocular manometry and the tonometer in both horses and cattle. Our results demonstrate that the Perkins handheld tonometer could be an additional tool for accurately measuring IOP in equine and bovine eyes. 相似文献
175.
S. Regodon A. Robina A. Franco J. M. Vivo Y. Lignereux 《Anatomia, histologia, embryologia》1991,20(2):129-138
Cranio-encephalic morphology of three breeds of dogs (Greyhound, Pointer and Pekinese at the rate of 10 subjects, 5 males and 5 females, in each one) has been radiologically observed. Radiographic negatives in dorso-ventral and latero-lateral positions were taken and analyzed before and after the visualisation of the encephalic cavity using barium sulfate. 18 cranio-encephalic measurements were chosen and interpreted statistically. The results showed that certain variables were more closely correlated with morphologic types of the cranium than others. We discuss the validity of the data applied for clinical diagnostic or osteo-archeology determinations. 相似文献
176.
Canine coronavirus induces apoptosis in cultured cells 总被引:1,自引:0,他引:1
Ruggieri A Di Trani L Gatto I Franco M Vignolo E Bedini B Elia G Buonavoglia C 《Veterinary microbiology》2007,121(1-2):64-72
Canine coronavirus (CCoV) is widespread in dogs in several countries and causes mild enteric illness evolving to severe enteritis in young pups. In in vitro cultures canine coronaviruses generally induce extensive cell death, however nature of the events leading to cell death remains largely unknown. We analysed the induction of cytopathic effect by CCoV in a canine fibrosarcoma cell line (A-72) in order to characterize the apoptotic effect in homologous cell system. Following CCoV infection A-72 cell line, which is permissive to CCoV, showed reduced growth rate, as detected by MTT assay, a standard colorimetric assay for measuring cellular proliferation, and underwent to apoptotic death. Starting from 24h after CCoV infection, cells morphology appeared dramatically changed, with cells rounding and detachment from culture surface. Morphologic and biochemical features of apoptosis, such as blebbing of the plasma membrane, translocation of phosphatidilserine to cell surface and annexin V positive staining, nuclear fragmentation, apoptotic bodies formation and DNA laddering, were detected in CCoV-infected cells. Propidium iodide staining of infected culture indicated the appearance of hypodiploid DNA peak corresponding to apoptotic cell population. Commonly to other animal coronavirus infection caspase-3 is likely to contribute to the execution phase of apoptosis induced by CCoV in A-72 cells since we found activation of enzymatic activity as well as procaspase-3 activating cleavage. Apoptotic death of infected cells is detrimental as it causes cell and tissue destruction as well as inflammatory responses. Therefore in the case of CCoV associated gastroenteritis, apoptosis of epithelial mucosa cells may be responsible for pathology induced by CCoV infection. 相似文献
177.
Gómez C Pinal L Franco J Carrillo JM Ramírez J 《Veterinary immunology and immunopathology》2007,117(3-4):249-253
A total of 41 isolates of Staphylococcus aureus obtained from bovine mastitis in 7 different states in Mexico were analyzed by the polymerase chain reaction (PCR) to determine the presence of encoding genes for enterotoxins A, B and C. The oligonucleotides were designed by specific regions of the sea, seb, sec genes. Surprisingly, none of the isolates presented the prospective amplification bands when they were run on agarose gels. On the contrary, reference strains CECT 976 SEA; CECT 5191 SEB; and CECT 4465 SEC showed the prospective amplification products. In order to confirm these results, enterotoxin production A, B, C, D, and E was determined by enzyme linked fluorescent assay (ELFA) using a MiniVIDAS system, on 15 Staphylococcus aureus selected at random from among the 41 isolates. None of the analyzed strains was positive to the test, whereas reference strains enterotoxins producing: CECT 976 SEA; CECT 5191 SEB; CECT 4465 SEC, CECT 4466 SED; CECT 5192 SEE produced concentrations of the toxins detected for this technique. The role of enterotoxins in the pathogenicity of S. aureus in bovine mastitis in Mexico is discussed. 相似文献
178.
D’Amico Michele E. Casati Enrico Andreucci Stefano Martini Marco Panzeri Laura Sechi Daniele El Khair Davide Abu Previtali Franco 《Journal of Soils and Sediments》2021,21(2):832-841
Journal of Soils and Sediments - Loess in Northern Italy has been usually considered deposited during the MIS 4-2 period, which corresponds to the last Pleistocene glacial cycle. In particular, no... 相似文献
179.
Seu R Phillips RJ Alberti G Biccari D Bonaventura F Bortone M Calabrese D Campbell BA Cartacci M Carter LM Catallo C Croce A Croci R Cutigni M Di Placido A Dinardo S Federico C Flamini E Fois F Frigeri A Fuga O Giacomoni E Gim Y Guelfi M Holt JW Kofman W Leuschen CJ Marinangeli L Marras P Masdea A Mattei S Mecozzi R Milkovich SM Morlupi A Mouginot J Orosei R Papa C Paternò T Persi del Marmo P Pettinelli E Pica G Picardi G Plaut JJ Provenziani M Putzig NE Russo F Safaeinili A Salzillo G 《Science (New York, N.Y.)》2007,317(5845):1715-1718
Mars' polar regions are covered with ice-rich layered deposits that potentially contain a record of climate variations. The sounding radar SHARAD on the Mars Reconnaissance Orbiter mapped detailed subsurface stratigraphy in the Promethei Lingula region of the south polar plateau, Planum Australe. Radar reflections interpreted as layers are correlated across adjacent orbits and are continuous for up to 150 kilometers along spacecraft orbital tracks. The reflectors are often separated into discrete reflector sequences, and strong echoes are seen as deep as 1 kilometer. In some cases, the sequences are dipping with respect to each other, suggesting an interdepositional period of erosion. In Australe Sulci, layers are exhumed, indicating recent erosion. 相似文献
180.
Fabiano T. P. K. T vora Anne C cile Meunier Aurore Vernet Murielle Portefaix Joë lle Milazzo Henri Adreit Didier Tharreau Oct vio L. Franco Angela Mehta 《水稻科学》2022,29(6):535-544
Rice genes OsDjA2 and OsERF104, encoding a chaperone protein and an APETELA2/ ethylene-responsive factor, respectively, are strongly induced in a compatible interaction with blast fungus, and also have function in plant susceptibility validated through gene silencing. Here, we reported the CRISPR/Cas9 knockout of OsDjA2 and OsERF104 genes resulting in considerable improvement of blast resistance. A total of 15 OsDjA2 (62.5%) and 17 OsERF104 (70.8%) T0 transformed lines were identified from 24 regenerated plants for each target and used in downstream experiments. Phenotyping of homozygous T1 mutant lines revealed not only a significant decrease in the number of blast lesions but also a reduction in the percentage of diseased leaf area, compared with the infected control plants. Our results supported CRISPR/Cas9-mediated target mutation in rice susceptibility genes as a potential and alternative breeding strategy for building resistance to blast disease. 相似文献