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91.
Aelurostrongylus abstrusus (Nematoda, Strongylida) in cats and associated risk factors have been investigated by classical coprology in central (site A) and southern (site B) Italy, i.e. by floatations with sugar and zinc sulphate solutions and a Baermann technique. Overall, 227 individual stool samples (i.e. 162 from site A and 65 from site B) were processed and risk factors were related to infection by binary logistic multiple-regression models. The presence of A. abstrusus was used as the dependent variable and the epidemiological data as independent variables. Twenty-eight (17.3%) and 12 (18.5%) cats were positive for A. abstrusus in sites A and B, respectively, both using the Baermann and flotation with zinc sulphate solution methods. Six and three (from site A and B, respectively) of the infected cats were negative for A. abstrusus when faeces were processed with sugar solution. Stray and free-ranging (P=0.357), young cats (P=0.008) and the presence of respiratory symptoms (P=0.000) were risk factors for A. abstrusus infection. The results suggest that A. abstrusus is spread in Italy. Furthermore, these results possibly include infection in the differential diagnosis of feline respiratory diseases and offer a correct diagnostic approach by using either a Baermann method or flotation with zinc sulphate solution in suspected cases.  相似文献   
92.
Platelet derived growth factor receptor (PDGFR)α and PDGFRβ are tyrosine kinase receptors that are overexpressed in 70–80% of human osteosarcomas (OSAs) and may be suitable therapeutic targets for specific kinase inhibitors (TKIs). Canine OSA shows histopathological and clinical features similar to human OSA, and is considered an excellent model in comparative oncology. This study investigated PDGF-A, PDGF-B, PDGFRα and PDGFRβ expression in 33 canine OSA samples by immunohistochemistry and in seven primary canine OSA cell lines by Western blot and quantitative PCR analysis.Immunohistochemical data showed that PDGF-A and PDGF-B are expressed in 42% and 60% of the OSAs analysed, respectively, while PDGFRα and PDGFRβ were expressed in 78% and 81% of cases, respectively. Quantitative PCR data showed that all canine OSA cell lines overexpressed PDGFRα, while 6/7 overexpressed PDGFRβ and PDGF-A relative to a normal osteoblastic cell line. Moreover, in vitro treatment with a specific PDGFR inhibitor, AG1296, caused a dose- and time-dependent decrease in AKT phosphorylation. Collectively, these data show that PDGFRs/PDGFs are co-expressed in canine osteosarcomas, which suggests that an autocrine and/or paracrine loop is involved and that they play an important role in the aetiology of OSA. PDGFRs may be suitable targets for the treatment of canine OSA with a specific TKI.  相似文献   
93.
Longevity is an increasingly important trait in beef cattle. Increased longevity decreases costs for the farmer and increases revenue. The objective of this research was to investigate the phenotypic relationship between type traits and longevity in Chianina beef cattle, and the relationship between production and longevity, to analyze the effect of voluntary culling. Data included records on reproductive, productive, and type traits provided by the National Association of Italian Beef Cattle Breeders from 6,395 Chianina cows. The average length of productive life was 1,829 d. The herd-year had a strong effect on the risk of culling. The effects of 22 type traits were analyzed. All the muscularity traits analyzed were highly significant (P < 0.01) and as a group had the largest effect on longevity, followed by dimension, refinement, and leg traits. Cows that calved before 35 mo of age had a lower probability of being culled than cows calving after 35 mo of age. Variation in herd size had a strong effect on risk ratio, with lower risk for intermediate classes. Cows with approximately one calf per year remained in the herd longer than did cows with fewer calves. Straight-legged animals had a 59% greater probability of being replaced than cows with a moderate angle to the hock, whereas sickle-legged animals had only a 3% higher probability of being culled than average cows. Udder conformation had no effect on longevity. In summary, results of this study indicate that herd-year effects and muscularity traits were the most important factors for longevity for Chianina cows among the factors studied.  相似文献   
94.
95.
Olea europaea L. leaf extract and derivatives: antioxidant properties   总被引:2,自引:0,他引:2  
This paper reports a very simple and fast method to collect eluates with high amounts of hydroxytyrosol, biotransforming Olea europaea L. leaf extract by a thermophilic beta-glycosidase immobilized on chitosan. Some phenolic compounds in the leaf tissue and in the eluates obtained by biotransformation are identified. To propose the eluates as natural substances from a vegetal source, their antioxidant properties have been compared with those of the leaf extract from which they are originated. The eluates possess a higher concentration of simple phenols, characterized by a stronger antioxidant capacity, than those available in extra virgin olive oils and in many tablets of olive leaf extracts, commercially found as dietetic products and food integrators.  相似文献   
96.
Bivalves filter large volumes of water and can concentrate organisms which are pathogenic for humans and animals. Our aim was to evaluate the presence of Cryptosporidium spp. in clams from the Adriatic coast (Abruzzo region) and genetically characterize the oocysts isolated from the clams. From March to July 2003, 960 specimens of clams (Chamelea gallina) present in nature were collected at 500 m from the Tordino, Tronto, Vibrata and Vomano river mouths on the Adriatic sea. The haemolymph and tissues were extracted from the specimens (240 per river mouth) after the specimens had been identified, measured and weighed (live weight). Immunofluorescence tests (IFA) were performed on pools (n = 32) of samples and oocysts of Cryptosporidium spp. were detected in 23 pools of C. gallina. To identify the Cryptosporidium species, all the pools IFA-positive were tested by a PCR assay specific for the Cryptosporidium outer wall protein (COWP) gene. Positive amplicons then were sequenced and analysed. Two pools of clams were positive for Cryptosporidium parvum Genotype 2 (the “bovine” i.e. zoonotic genotype). This is the first time that C. parvum was found in clams from the Adriatic sea in Italy and the case might be of public health importance.  相似文献   
97.
Lactoferrin (Lf) is a non-haem iron-binding glycoprotein with a molecular weight of about 80 kDa, synthesized by glandular epithelial cells and stored in the secondary granules of neutrophils. The physiological significance of Lf is related to non-specific immune defence against pathogens, immunomodulatory activity, iron homeostasis, antioxidant properties and regulation of cell growth. Lf is a bioactive component of the mammary secretions and its modulatory and defensive functions do affect the newborn and the mammary gland as well. In this work a bovine mammary epithelial cell line (BME-UV1) was used as an in vitro model of the bovine mammary epithelium to examine the protective role of exogenous bovine Lf (bLf) against the cytotoxic damage induced by bacterial lipopolysaccharides (LPS) and the endogenous bLf mRNA expression after LPS exposure. In the in vitro model used, exogenous bLf exerts a protective effect against endotoxin cytotoxicity, which could be mediated by the LPS-neutralizing capability of bLf. In addition, in BME-UV1 cells the response to LPS exposure does not involve bLf mRNA expression, suggesting that this cell line lack of functional LPS-responsive elements.  相似文献   
98.
Anoplocephala perfoliata (Cestoda, Cyclophyllidea), the commonest intestinal tapeworm of horses, can cause colic, intussusceptions, ileal impactions and intestinal perforations. Common diagnostic techniques for A. perfoliata infection, i.e. coprology and serology, show inherent limitations in terms of sensitivity and specificity and new approaches are thus required. Hence, the present study compared the reliability of coprological, serological (i.e. ELISA) and molecular (i.e. nested PCR) methods in detecting A. perfoliata infection in naturally infected horses and in horses treated with a combination of ivermectin and praziquantel. Of 42 horses subjected to coprological examination, 16 and 26 resulted negative and positive, respectively for the presence of A. perfoliata eggs at the coprological examination. The 26 coprologically positive animals were also positive by nested PCR. Fifteen out of the 16 horses coprologically negative were negative at the molecular assay, while one yielded a PCR product detectable on an agarose gel. Eighteen out of 26 positive horses were treated with a combination of ivermectin 18.7 mg/g and praziquantel 140.3mg/g and resulted subsequently negative by coprology and nested PCR performed 2 weeks after treatment. All infected and untreated animals had a high ELISA test optical density indicating high infection intensity and associated risk of colic. However, high optical density values were also obtained in four horses post-treatment and in three horses that were negative on molecular and coprological analysis. The results of the present work indicate that the nested PCR assay represents a valid method for the specific molecular detection of A. perfoliata in faecal samples collected from naturally infected horses and may have advantages over coprological and serological approaches for diagnosing A. perfoliata infection.  相似文献   
99.
Using theonellasterol as a novel FXR antagonist hit, we prepared a series of semi-synthetic derivatives in order to gain insight into the structural requirements for exhibiting antagonistic activity. These derivatives are characterized by modification at the exocyclic carbon-carbon double bond at C-4 and at the hydroxyl group at C-3 and were prepared from theonellasterol using simple reactions. Pharmacological investigation showed that the introduction of a hydroxyl group at C-4 as well as the oxidation at C-3 with or without concomitant modification at the exomethylene functionality preserve the ability of theonellasterol to inhibit FXR transactivation caused by CDCA. Docking analysis showed that the placement of these molecules in the FXR-LBD is well stabilized when on ring A functional groups, able to form hydrogen bonds and π interactions, are present.  相似文献   
100.
The aim of this study was to estimate genetic associations between alternative somatic cell count (SCC) traits and milk yield, composition and udder type traits in Italian Jersey cows. Alternative SCC traits were test‐day (TD) somatic cell score (SCS) averaged over early lactation (SCS_150), standard deviation of SCS of the entire lactation (SCS_SD), a binary trait indicating absence or presence of at least one TD SCC >400,000 cells/ml in the lactation (Infection) and the ratio of the number of TD SCC >400,000 cells/ml to total number of TD in the lactation (Severity). Heritabilities of SCC traits, including lactation‐mean SCS (SCS_LM), ranged from 0.038 to 0.136. Genetic correlations between SCC traits were moderate to strong, with very few exceptions. Unfavourable genetic associations between milk yield and SCS_SD and Infection indicated that high‐producing cows were more susceptible to variation in SCC than low‐producing animals. Cows with deep udders, loose attachments, weak ligaments and long teats were more susceptible to an increase of SCC in milk. Overall, results suggest that alternative SCC traits can be exploited to improve cow's resistance to mastitis in Italian Jersey breed.  相似文献   
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