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41.
Agricultural herbicides are among the most commonly used pesticides worldwide, posing serious concerns for both humans, exposed to these chemicals through many routes, and the environment. To clarify the effects of three herbicides as commercial formulations (namely, Pointer, Silglif, and Proper Energy), parameters related to oxidative issues were investigated on an autochthonous wine yeast strain. It was demonstrated that herbicides were able to affect the enzymatic activities of catalase and superoxide dismutase, as well as to induce carbonylation and thiol oxidation as post-translational modifications of proteins. Saccharomyces cerevisiae is an optimal model system to study responses to xenobiotics and oxidative stress. Thus, the results obtained could further the understanding of mechanisms underlying the toxicity of herbicides.  相似文献   
42.
Magnetic resonance imaging fat suppression techniques are commonly used for diagnosis of canine spinal disease, however, studies comparing different techniques are currently lacking. This retrospective, methods comparison study aimed to evaluate water excitation and STIR MRI pulse sequences for visualization of canine lumbar spinal nerve roots. For inclusion, all dogs had to have dorsal planar MRI studies of the lumbar spine using both sequences. Visual grading analysis was used for scoring the following five criteria: degree of fat suppression; nerve root visualization; subjective tissue contrast; presence of noise; and overall better image quality. Scores were independently recorded by three board‐certified veterinary radiologists on two separate occasions, 3‐6 weeks apart. A total of 90 dogs were sampled. A two‐tailed t‐test showed that there were significant differences in all scored parameters (P < 0.00001), with the exception of noise (P = 0.47343), and that the water excitation sequence scored higher in all cases excluding noise. A Gwets AC kappa for intraobserver and interobserver reliability showed “almost perfect” agreement for the nerve roots in both tests (intra: k = 0.88; inter: k = 0.90). Intraobserver agreement was “substantial” for the degree of fat suppression (k = 0.68), subjective tissue contrast (k = 0.75), and overall better image quality (k = 0.76) and it was “fair” for the noise (k = 0.46). Interobserver agreement was “moderate” for the degree of fat suppression (k = 0.53), subjective tissue contrast (k = 0.63), and overall better image quality (k = 0.66) and “slight” for noise (k = 0.25). These findings supported using the water excitation pulse sequence for fat‐suppressed MRI of canine lumbar spinal nerve roots.  相似文献   
43.
Treatment options for dogs with metastatic (stage III) splenic hemangiosarcoma are limited. A doxorubicin‐based chemotherapy regimen is commonly administered; however, there are no published data to support this practice. The aim of this study was to investigate the impact of maximum‐tolerated‐dose chemotherapy (MTD), metronomic chemotherapy (MC) and no adjuvant treatment on outcome in dogs with stage III splenic hemangiosarcoma undergoing splenectomy. Medical records of dogs with stage III splenic hemangiosarcoma that underwent splenectomy followed by MTD chemotherapy, MC or no adjuvant treatment were retrieved. Time to progression (TTP), survival time (ST) and toxicity were evaluated. One hundred three dogs were identified: 23 received adjuvant MTD, 38 MC and 42 were not medically treated. Overall median TTP and ST were 50 (95% confidence interval [CI], 39‐61) and 55 days (95% CI, 43‐66), respectively. Dogs treated with adjuvant MTD had a significantly longer TTP and ST compared with dogs receiving MC (median TTP, 134 vs 52 days, P = .025; median ST, 140 vs 58 days, P = .023, respectively). Dogs treated by splenectomy only had the shortest median TTP (28 days) and ST (40 days). However, treatment‐related adverse events (AEs) were significantly more frequent in the MTD group (P = .017). The outcome for dogs with metastatic splenic hemangiosarcoma is poor. While MTD showed greater efficacy compared to MC, toxicity was higher in this group. Treatment‐related AEs need to be carefully balanced against this modest survival prolongation when offering adjuvant MTD to dogs with advanced stage hemangiosarcoma.  相似文献   
44.
Three subtypes (H1N1, H1N2, and H3N2) are currently diffused worldwide in pigs. The H1N2 subtype was detected for the first time in Italian pigs in 1998. To investigate the genetic characteristics and the molecular evolution of this subtype in Italy, we conducted a phylogenetic analysis of whole genome sequences of 26 strains isolated from 1998 to 2010. Phylogenetic analysis of HA and NA genes showed differences between the older (1998-2003) and the more recent strains (2003-2010). The older isolates were closely related to the established European H1N2 lineage, whereas the more recent isolates possessed a different NA deriving from recent human H3N2 viruses. Two other reassortant H1N2 strains have been detected: A/sw/It/22530/02 has the HA gene that is closely related to H1N1 viruses; A/sw/It/58769/10 is an uncommon strain with an HA that is closely related to H1N1 and an NA similar to H3N2 SIVs. Amino acid analysis revealed interesting features: a deletion of two amino acids (146-147) in the HA gene of the recent isolates and two strains isolated in 1998; the presence of the uncommon aa change (N66S), in the PB1-F2 protein in strains isolated from 2009 to 2010, which is said to have contributed to the increased virulence. These results demonstrate the importance of pigs as mixing vessels for animal and human influenza and show the presence and establishment of reassortant strains involving human viruses in pigs in Italy. These findings also highlighted different genomic characteristics of the NA gene the recent Italian strains compared to circulating European viruses.  相似文献   
45.
Wheat germinating caryopses may represent a starting point for the Fusarium Head Blight disease; however, only few studies concern the defence repertoire of wheat caryopses against fungal challenge. The germinating caryopses of two wheat commercial varieties (Blasco and Sagittario), differentially susceptible to FHB in the field, were inoculated with F. graminearum and the redox status in the interaction milieu, oxylipin production, the expression profile of some host-defence related genes, and programmed cell death in the aleuronic layer, were analysed. In Sagittario, the redox balance was profoundly modified and 9-oxylipins accumulated during fungal contamination. In this variety, F. graminearum produced a high quantity of deoxynivalenol whilst programmed cell death, also through metacaspases activation, was enhanced in the aleuronic layer of its caryopses. In Blasco, the expression of tolerance factors such as Pathogenesis-Related-protein1, glucosyl-transferase and glutathione transferase genes was up-regulated consequent to infection. Results show that unscavenged ROS and 9-oxylipins may be related to deoxynivalenol accumulation in the germinating caryopses of wheat after F. graminearum infection.  相似文献   
46.
Interveinal chlorosis and leaf margin wrinkling are widespread symptoms of Cannabis sativa. They are traditionally attributed to the so-called hemp streak virus (HSV), but its existence has not been demonstrated yet. To our knowledge, no molecular investigation has so far been performed in order to identify the causal agent of this symptomatology, we therefore decided to use traditional and molecular virology techniques to better characterize symptoms and pursue the etiological agent. No pathogenic virus was found by using targeted PCR reactions and by RNA sequencing, whereas we were able to detect the Cannabis cryptic virus (CanCV) with both techniques. We, therefore, developed an RT-qPCR assay based on a CanCV-specific TaqMan probe and applied it to a wide range of symptomatic and symptomless plants, using a two-step (for quantification), or a one-step (for fast detection) protocol. Both symptoms and the virus were only shown to be transmitted vertically and did not pass via mechanical inoculation or grafting, though we could not find any cause-effect correlation between them. In fact, the virus was found in all the tested hemp samples, and its abundance varied greatly between different accessions and individuals, independently from the presence and severity of symptoms. The suggestion that hemp streak is caused by a virus is therefore questioned. Some abiotic stresses seem to play a role in triggering the symptoms but this aspect needs further investigation. For breeding purposes, a selection of parental plants based on the absence of symptoms proved to be efficient in containment of the disease.  相似文献   
47.
48.
BACKGROUND: The increased sophistication of imaging techniques in veterinary medicine allows the detection of a wide variety of intracranial and intraspinal lesions; however, imaging often does not provide a definitive diagnosis for nervous system (NS) lesions. Cytology is emerging as a useful diagnostic tool for obtaining a fast and accurate assessment of NS lesions, but little information is available for dogs and cats. OBJECTIVES: The purpose of this study was to assess the accuracy of cytologic evaluation of squash samples from NS lesions in dogs and cats and to consider cytology-based diagnostic guidelines and sources of misdiagnosis. METHODS: Cytologic specimens from masses localized in the central and peripheral NS taken during surgery or postmortem examination were classified into 3 groups according to the final histopathologic diagnosis: Group 1 = completely correct diagnosis, when the cytologic diagnosis and final histologic diagnosis were exactly correlated; Group 2 = partial correlation, when the cytologic diagnosis only partially correlated with the final histologic diagnosis, and Group 3 = no correlation, when the cytologic diagnosis was incorrect and there was no correlation with the general histologic type of lesion. The diagnostic accuracy of cytopathology was calculated by considering the histopathologic diagnosis as the "gold standard," and calculating a 95% confidence interval (CI). RESULTS: A total of 42 animals (33 dogs and 9 cats) were included in the study. The cytologic diagnoses were classified in Group 1 for 32 cases (76%; 95% CI 0.63-0.89), in Group 2 for 6 cases (14%; 95% CI 0.04-0.25), and in Group 3 for 4 cases (10%; 95% CI 0.006-0.18). Considering both complete and partial correlation as an adequate result, cytologic diagnosis was satisfactory in 90% of biopsies. CONCLUSIONS: Although the current series of cases is relatively small, cytologic evaluation of squash preparations can be considered a fairly accurate and reliable tool in the diagnosis of NS lesions.  相似文献   
49.
Soil organic matter (SOM) produces positive effects on multiple soil properties. Increasing its level also provides an opportunity to reduce atmospheric concentration of carbon dioxide (CO2). Recycling animal manure and returning crop residue are among the main practices to enhance organic carbon (C) stock in arable croplands. This study analysed data of soil organic carbon (SOC) stocks from a medium-term field trial (established in 1992) through a Hénin–Dupuis-based equation to determine the proportion of different organic materials retained in the soil as SOM.The treatments included in the experiment simulated different typical management techniques and implied the application to the soil of various organic materials, i.e. cattle slurry, cattle farmyard manure, maize straw, root, maize and ley stubble. Soil organic carbon and total nitrogen (N) (Kjeldhal N) were measured in the 0–30 cm layer during spring 1999 and spring 2003. The relationship between SOC and N stocks measured in 1999 and 2003 and the annual additions of C and N was described by the Hénin–Dupuis-based equation, assuming the presence of two C and N pools (stable and fresh).Our results showed that the application of farmyard manure, slurry and maize straw induced higher C and N content compared to the application of urea without return of crop residue. The different levels of urea application did not produce any significant difference in C and N soil content.We found that approximately 2% of SOC is lost to the atmosphere annually. Furthermore, the amount of C and N retained in the soil each year varied by organic materials: 46% C and 44% N with farmyard manure, 26% C and 11% N with slurry, 28% C and 10% N with root and 6% C with maize straw and ley stubble.These results were used to inform an estimate of C lost or removed to/from atmosphere following manure application and crop residue return for the compilation of greenhouse gas inventories. We found that the most C conservative management is the production and spreading of farmyard manure and that increasing amounts of mineral N fertilizer did not affect the C sequestration extent.  相似文献   
50.

Objectives

To review the methods for verifying the needle position while performing epidural anaesthesia in dogs, and to discuss the advantages, disadvantages, usefulness and reliability of each technique in the experimental and clinical research setting.

Databases used

PubMed, Scopus, Google Scholar and the Basel University Library online catalogues; the latter, which was provided by the University of Berne, were used as databases. The results were filtered manually based on the titles and abstracts in order to narrow the field.

Conclusions

Besides some drawbacks, including the potential side effects of contrast medium injection, which may limit its routine use in clinical patients, epidurography should still be regarded as one of the most reliable techniques to verify needle position in dogs. Ultrasonography, electrical nerve stimulation, loss of resistance and the hanging drop technique are regarded as less invasive than epidurography and, for this reason, their use may be more applicable to clinical patients. However, these methods have been described in only a few published reports, all of which involved a limited number of dogs. Finally, the detection of epidural pressure waves has been investigated more extensively in dogs, and the findings of these studies suggest that this technique may be used to verify epidural needle placement for experimental and clinical research, on condition that all the negative subjects are excluded from the study.  相似文献   
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