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941.
Mariel Josue Bizarro Adriana Giongo Luciano Kayser Vargas Luiz Fernando Wurdig Roesch Kelsey Annette Gano Enilson Luiz Saccol de Sá Luciane Maria Pereira Passaglia Pedro Alberto Selbach 《Biology and Fertility of Soils》2011,47(3):357-362
Due to their ecologic and economic importance, bradyrhizobia have been extensively studied in recent years. Since 1992, Bradyrhizobium elkanii SEMIA 587 and SEMIA 5019 and Bradyrhizobium japonicum SEMIA 5079 and SEMIA 5080 have been widely used in most Brazilian soybean fields. The objective of this work was to estimate
the genetic variability of bradyrhizobial isolates recovered from soils under rhizobial inoculation and different soil managements.
Only 25% of the isolates demonstrated high similarities to the original strains, and a strong correlation was obtained between
the bradyrhizobial genetic variability and soil management. A high level of genetic diversity was observed both within isolates
(H = 5.46) as well as among the different soil practices. Soil under no-tillage presented a higher bradyrhizobia diversity compared
with bradyrhizobia isolated from soil under conventional tillage. Serological characterization also indicated that B. elkanii strains SEMIA 587 and SEMIA 5019 were more competitive and presented a higher nodular occupancy capacity than strains belonging
to B. japonicum species in Southern Brazilian soils. 相似文献
942.
Dervisis NG Dominguez PA Newman RG Cadile CD Kitchell BE 《Journal of the American Animal Hospital Association》2011,47(3):170-178
Hemangiosarcoma (HSA) is an aggressive disease that is fairly common in the dog. The authors evaluated a doxorubicin, dacarbazine, and vincristine (DAV) combination protocol in dogs with nonresectable stage II and stage III HSA. Twenty-four dogs were enrolled in this prospective, phase 2 study. Doxorubicin and dacarbazine were administered on day 1 while vincristine was administered on days 8 and 15. The protocol was repeated every 21 days for a maximum of six cycles or until disease progression. Toxicity and efficacy were assessed by clinical and laboratory evaluation and by questionnaires completed by the owners. Of the 24 included dogs, 19 were evaluable for response. The response rate (including five complete responses and four partial responses) was 47.4%. Median time to tumor progression was 101 days and median overall survival was 125 days. Significant toxicities were noted, including 41 high-grade hematologic and 12 high-grade gastrointestinal toxic events. Five dogs discontinued treatment due to chemotherapy-related toxicities, but no treatment-related deaths occurred. Multivariate analysis identified patient age (relative risk [RR], 2.3, P=0.049) to be negatively associated with time to progression whereas dacarbazine dose reductions (RR, 0.06, P=0.031) were positively associated with time to progression. Dacarbazine dose reduction was the sole factor positively associated with overall survival (RR, 0.28, P=0.015). In conclusion, the DAV combination appears to offer clinical responses and may prolong survival in dogs with advanced-stage HSA. 相似文献
943.
Huerta B Maldonado A Ginel PJ Tarradas C Gómez-Gascón L Astorga RJ Luque I 《Veterinary microbiology》2011,150(3-4):302-308
This study reports the susceptibility to antimicrobial agents of staphylococci (n=105) isolated from dogs, and the factors associated with this resistance. The study animals were 23 healthy dogs (group A), 24 with first-time pyoderma (group B), and 27 with recurrent pyoderma that had undergone long-term antibiotic treatment (group C). Staphylococci were more commonly isolated from the pyoderma-affected than the healthy dogs (p<0.0001). Some 78% of the isolates were resistant to at least one antimicrobial agent. Resistance to amoxicillin-clavulanate, cephalosporins (OR 4.29, 95% CI [1.15, 16.3] respectively), enrofloxacin (OR 9.47, 95% CI [1.53, 58.5]) and ciprofloxacin (OR 79.7 95% CI [3.26, 1947.4]) was more common among group C isolates. Some 32% of all the isolates were multiresistant (MR) and 10.4% were methicillin-resistant (MRS). The probability of isolating MRS staphylococci in group C increased by a factor of four (95% CI [1.18, 17.9]) compared to A plus B. Multi-resistant (MR) isolates were obtained more commonly from urban than rural dogs (OR 3.79, 95% CI [1.09, 13.17]). All the MRS staphylococci encountered were obtained from urban dogs and more commonly from male dogs (p=0.07). This study shows that dogs bred in urban habitat, with a history of antibiotic therapy in the past year represents significant risk of being carriers of isolates resistant to methicillin (MRS) and other antimicrobials. These factors should be considered before applying an antimicrobial treatment in veterinary clinics. 相似文献
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947.
Juan Francisco Herencia Pedro A. García-Galavís José Antonio Ruiz Dorado Celia Maqueda 《Scientia Horticulturae》2011
Organic farming is growing rapidly in its potential for producing healthy foods and has been adopted in a wide range of climate and soil types. The perception among consumers is that organically produced crops possess higher nutritional quality. However, there are many factors that can affect the nutritional quality of crops, and few studies have been able to account for these differences. 相似文献
948.
Background
Plant viruses are useful expression vectors because they can mount systemic infections allowing large amounts of recombinant protein to be produced rapidly in differentiated plant tissues. Pepino mosaic virus (PepMV) (genus Potexvirus, family Flexiviridae), a widespread plant virus, is a promising candidate expression vector for plants because of its high level of accumulation in its hosts and the absence of severe infection symptoms. We report here the construction of a stable and efficient expression vector for plants based on PepMV. 相似文献949.
Vanessa M. B. dos Santos Pedro Henrique N. Pinto Mario Felipe A. Balaro Juliana D. R. Santos Augusto R. Taira Caroline G. do Espirito Santo Fernanda M. Gonçalves Jeferson F. da Fonseca Felipe Z. Brandão 《Reproduction in domestic animals》2020,55(10):1446-1454
The aim of this work was to determine whether a cervical dilation protocol (CDP) composed of only oxytocin can be used to perform transcervical (non-surgical) embryo transfer in sheep (NSET) without affecting the viability of the corpus luteum (CL). Likewise, we evaluated whether a cervical transposing test with a Hegar dilator (CT Hegar test), performed at oestrous time, could be used to screen ewes for NSET (greater or lower chances to transpose the cervix). For that, oestrous and ovulation synchronization was performed in 25 Santa Inês ewes to induce the dioestrous condition. Animals went through the following CDP in a crossover design: E + OX, oestradiol benzoate (100 µg intravenously [IV]) and oxytocin (100 IU IV); OX, oxytocin (100 IU IV); and SAL, saline solution (IV). Using a Hegar dilator, cervical transposing attempts were performed at oestrous (D0) and dioestrous time (D8). The viability of the CL (morphology, luteal blood flow and progesterone values) was evaluated by ultrasonography (colour Doppler and B-mode) and by serum progesterone measurement from D7 to D13. The cervical transposing rate was lower for the SAL group (64%; 16/25; p < .05) and did not differ between the E + OX (88%; 22/25, p > .05) and OX (84%; 21/25, p > .05) groups. No treatment affected the CL viability. The CT Hegar test showed a high sensitivity (85.7%–93.3%), satisfactory accuracy (72%–84%), low false-negative rate (6.7%–14.6%), but high false-positive rate (46%–66.7%). In conclusion, a CDP protocol composed exclusively of oxytocin can lead to good cervical transposing rates and does not affect the viability of the CL. In addition, a screening test (CT Hegar) performed at oestrus can identify ewes for which cervical transposing will likely not occur at NSET. 相似文献
950.
Isadora C. Pereira Jorge L. Badel Pedro M. P. Vidigal Adryelle A. Sousa Samuel A. Santos Lúcio M. S. Guimarães Acelino C. Alfenas 《Plant pathology》2021,70(3):555-566
Erwinia psidii is a gram-negative bacterium that threatens both guava and eucalypt plantations in several countries. Despite the economic importance of both crops, nothing is currently known about the molecular mechanisms underlying E. psidii pathogenicity and, consequently, how it evolved to infect Eucalyptus species besides its presumed native host Psidium guajava. In this study, we predicted putative type III secretion system effectors that may play important roles during plant–E. psidii interactions and conducted effector structure and phylogenetic analyses to gain important insights into their function and evolution. For that, the whole genomes of four E. psidii strains that exhibit differential aggressiveness towards eucalypt clones were sequenced and their effector repertoires predicted based on sequence identity with known effectors of the model phytopathogen Erwinia amylovora. Only proteins sharing significant sequence identity with the DspE and Eop1 effectors were found. Here, it is shown that these two E. psidii effectors retain all structural characteristics of their corresponding protein superfamilies, but exhibit allelic variations that are consistent with the observed aggressiveness differences between strains. Phylogenetic analyses revealed that whereas E. psidii housekeeping gene sequences are more closely related to those from Erwinia tracheiphila, the effector (either nucleotide or amino acid) sequences are more closely related to their Pantoea agglomerans counterparts, suggesting that dspE and eop1 were both acquired through horizontal gene transfer from the latter bacterial species. The results of this study provide important insights on E. psidii pathogenicity and set the stage for future effector functional studies. 相似文献