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121.
Highly pathogenic avian influenza (HPAI) viruses of the H5 and H7 subtype pose a major public health threat due to their capacity to cross the species barrier and infect mammals, for example dogs, cats and humans. In the present study we tested the capacity of selected H7 and H5 HPAI viruses to infect and to be transmitted from infected BALB/c mice to contact sentinels. Previous experiments have shown that viruses belonging to both H5 and H7 subtypes replicate in the respiratory tract and central nervous system of experimentally infected mice. In this study we show that selected H7N1 and H5N1 HPAI viruses can be transmitted from mouse-to-mouse by direct contact, and that in experimentally infected animals they exhibit a different pattern of replication and transmission. Our results can be considered as a starting point for transmission experiments involving other influenza A viruses with α 2-3 receptor affinity in order to better understand the viral factors influencing transmissibility of these viruses in selected mammalian species.  相似文献   
122.
The aim of the present study was to evaluate the sensitivity and specificity of urine KIM-1 and urine GGT for the detection of naturally-occurring AKI, compared to healthy control dogs, dogs with stable chronic kidney disease (CKD), and dogs with lower urinary tract disorders (LUTD). The study included AKI grade 1 (n?=?21), AKI grade 2 to 5 (n?=?11), stable CKD (n?=?11), LUTD (n?=?15), and healthy dogs (n?=?37). Urine KIM-1 (ng/mg) and GGT (U/l) were normalized to urine creatinine (uCr). Statistically significant difference in KIM/uCr (p?=?0.0007) and GGT/uCr (p?<?0.0001) was found among the study groups. Area under the curve (AUC) for KIM-1/uCr and GGT/uCr as predictors of AKI was 0.81 and 0.91 respectively. Values of KIM-1/uCr of 0.73 ng/mg and of GGT/uCr of 54.33 showed the best combination of sensitivity and specificity (75% and 75.6%; 85.7% and 89.1% respectively). A significant positive correlation (p?<?0.0001) between KIM-1/uCr and GGT/uCr was found. Both urine KIM-1/uCr and GGT/uCr seemed to be potentially good markers for the diagnosis of AKI. Dogs with AKI showed significantly higher levels of urine KIM-1/uCr and urine GGT/uCr, compared with healthy dogs. Caution should be used in the evaluation of elevated urine KIM-1/uCr and GGT/uCr in dogs with pre-existing CKD and/or LUTD. Urine KIM-1/uCr and GGT/uCr might have a significant clinical utility, as complementary test, particularly in diagnosis early, non-azotemic stages of AKI.  相似文献   
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The study of the immune response in several types of tumours has been rapidly increasing in recent years with the dual aim of understanding the interactions between neoplastic and immune cells and their importance in cancer pathogenesis and progression, as well as identifying targets for cancer immunotherapy. Despite being considered one of the most immunogenic tumour types, melanoma can progress in the presence of abundant lymphocytic infiltration, therefore suggesting that the immune response is not able to efficiently control tumour growth. The purpose of this study was to investigate whether the density, distribution and grade of tumour‐infiltrating lymphocytes (TILs) in 97 canine melanocytic tumours is associated with histologic indicators of malignancy and can be considered a prognostic factor in the dog. As a further step in the characterization of the immune response in melanocytic tumours, an immunohistochemical investigation was performed to evaluate the two main populations of TILs, T‐lymphocytes (CD3+) and B‐lymphocytes (CD20+). The results of our study show that TILs are present in a large proportion of canine melanocytic tumours, especially in oral melanomas, and that the infiltrate is usually mild. The quantity of CD20+ TILs was significantly associated with some histologic prognostic factors, such as the mitotic count, the cellular pleomorphism and the percentage of pigmented cells. Remarkably, a high infiltration of CD20+ TILs was associated with tumour‐related death, presence of metastasis/recurrence, shorter overall and disease‐free survival, increased hazard of death and of developing recurrence/metastasis, hence representing a potential new negative prognostic factor in canine melanocytic tumours.  相似文献   
126.
In the last decades, research has focused on the capabilities of microbes to secrete exopolysaccharides (EPS), because these polymers differ from the commercial ones derived essentially from plants or algae in their numerous valuable qualities. These biopolymers have emerged as new polymeric materials with novel and unique physical characteristics that have found extensive applications. In marine microorganisms the produced EPS provide an instrument to survive in adverse conditions: They are found to envelope the cells by allowing the entrapment of nutrients or the adhesion to solid substrates. Even if the processes of synthesis and release of exopolysaccharides request high-energy investments for the bacterium, these biopolymers permit resistance under extreme environmental conditions. Marine bacteria like Bacillus, Halomonas, Planococcus, Enterobacter, Alteromonas, Pseudoalteromonas, Vibrio, Rhodococcus, Zoogloea but also Archaea as Haloferax and Thermococcus are here described as EPS producers underlining biopolymer hyperproduction, related fermentation strategies including the effects of the chemical composition of the media, the physical parameters of the growth conditions and the genetic and predicted experimental design tools.  相似文献   
127.
Hepatitis E virus (HEV) strains belonging to the Orthohepevirus genus are divided into four species (A–D). HEV strains included in the Orthohepevirus A species infect humans and several other mammals. Among them, the HEV‐3 and HEV‐4 genotypes are zoonotic and infect both humans and animals, of which, pigs and wild boar are the main reservoirs. Viruses belonging to the Orthohepevirus C species (HEV‐C) have been considered to infect rats of different species and carnivores. Recently, two studies reported the detection of HEV‐C1 (rat HEV) RNA in immunocompromised and immunocompetent patients, suggesting a possible transmission of rat HEV to humans. The role of rats and mice as reservoir of HEV and the potential zoonotic transmission is still poorly known and deserves further investigation. To this purpose, in this study, the presence of HEV RNA was investigated in the intestinal contents and liver samples from 47 Black rats (Rattus rattus) and 21 House mice (Mus musculus) captured in four pig farms in Northern Italy. The presence of both Orthohepevirus A and C was investigated by the real‐rime RT‐PCR specific for HEV‐1 to HEV‐4 genotypes of Orthohepevirus A species and by a broad spectrum hemi‐nested RT‐PCR capable of detecting different HEV species including rat HEV. The intestinal content from two Black rats resulted positive for HEV‐C1 RNA and for HEV‐3 RNA, respectively. None of the House mice was HEV RNA positive. Sequence analyses confirmed the detection of HEV‐C1, genotype G1 and HEV‐3 subtype e. The viral strain HEV‐3e detected in the rat was identical to swine HEV strains detected in the same farm. Liver samples were negative for the detection of either rat HEV or HEV‐3.  相似文献   
128.
The aim of this retrospective study was to evaluate the results obtained in 353 dogs (420 eyes) using two different surgical techniques for correction of a prolapsed gland of the third eyelid: the Morgan's pocket technique and a technique combining Morgan's approach with a slightly modified periosteal anchoring technique of Stanley and Kaswan. The pocket technique was used in 234 eyes and the combined technique in 186 eyes. Successful repositioning was obtained in 95% of all cases, with recurrence occurring in 5%. The recurrence rate in large breed dogs such as the English Bulldog and Boxer was lower with the combined technique than with the pocket technique.  相似文献   
129.
The aim of the study was to test the interaction between Thr and Gly in low crude protein (CP) diets in 7 to 28 d broilers on production performance and plasma metabolites. A total of 2,040 broilers were allocated to 17 treatments. A positive control (PC) diet (20.5% CP) was formulated to be adequate in dietary Thr and Gly. A negative control (NC) diet (18.5% CP, deficient in Thr and Gly) was supplemented with crystalline l-Thr and Gly to obtain a 4 Thr × 4 Gly design. Dietary Thr was tested at an apparent faecal digestibility (AFD) Thr-to-Lys ratio, which was 55%, 58%, 61% or 64%, and dietary Gly was tested at an AFD (Gly + Ser)-to-Lys ratio, which was 135%, 142%, 149% or 156%. Plasma samples were collected at 28 d. The low CP diet, formulated at 64% Thr and 156% Gly, resulted in a higher body weight gain (BWG) (P < 0.01) and similar feed conversion ratio (FCR) as the high CP treatment (PC). FCR was improved (P < 0.001) by l-Thr supplementation. Quadratic response to dietary Thr was significant for feed intake (FI), BWG and FCR (P < 0.01). A near-significant interaction for Thr × Gly was observed for FI and BWG (Plinear = 0.091 and P = 0.074, respectively). Gly did not affect production performance. An interaction between Thr × Gly on plasma free AA level was observed (P < 0.05). Free AA concentration in plasma linearly decreased with increase in AFD Thr-to-Lys ratio, and increased with increase in AFD (Gly + Ser)-to-Lys ratio. Plasma uric acid concentration was higher in PC than in all of the other diets, and plasma triglyceride concentration was decreased by l-Thr supplementation, but not by Gly. In conclusion, Gly was not limiting for growth at low dietary CP level unless Thr was deficient, showing that adequate amounts of Thr in broiler diets can overcome marginal supply of Gly and Ser and allow reduction of dietary CP from 20.5% to 18.5% for broilers from 7 to 28 d of age.  相似文献   
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