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51.
The live microbiota ecosystem in the intestine plays a critical role in maintaining the normal physiological and psychological functions in both animals and human beings. However, the chronic effect of microbiota disturbances during prenatal and neonatal developing periods on animal's health remains less studied. In the current study, pregnant ICR mice were fed with an antibiotic diet (7-g nebacitin [bacitracin-neomycin sulphate 2:1]/kg standard diet) from day 14 of conception, and their offspring were provided with the same diet till the termination of the experiments. Dams treated with antibiotics showed increased body weight along with enlarged gut. Antibiotic-treated offspring revealed decreased bodyweight, increased food, water, and sucrose intake. Administration of antibiotics affected corticosterone responsivity to acute 20 min restraint challenge in male pups. In behavior tests, female pups showed decreased movement in open field while male pups revealed decreased latency to open arms in elevated plus maze test and immobility time in tail suspension test. Together, these results suggested that early antibiotic exposure may impact on the food intake, body weight gain, and emotional behavior regulation in mice.  相似文献   
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The equine herpesviruses are major infectious pathogens that threaten equine health. Equine herpesvirus 4 (EHV-4) is an important equine pathogen that causes respiratory tract disease, known as rhinopneumonitis, among horses worldwide. EHV-4 genome manipulation with subsequent understanding of the viral gene functions has always been difficult due to the limited number of susceptible cell lines and the absence of small-animal models of the infection. Efficient generation of mutants of EHV-4 would significantly contribute to the rapid and accurate characterization of the viral genes. This problem has been solved recently by the cloning of the genome of EHV-4 as a stable and infectious bacterial artificial chromosome (BAC) without any deletions of the viral genes. Very low copy BAC vectors are the mainstay of present genomic research because of the high stability of inserted clones and the possibility of mutating any gene target in a relatively short time. Manipulation of EHV-4 genome is now feasible using the power of BAC technology, and should aid greatly in assessing the role of viral genes in the virus-host interaction.  相似文献   
53.
Hamada MS  Yin Y  Chen H  Ma Z 《Pest management science》2011,67(11):1411-1419
Rhizoctonia cerealis, the causal agent of sharp eyespot on wheat, was not considered to be an important pathogen for many years. Recently, the disease has become endemic in many countries except for South America. The disease has created a new threat to world wheat production because the damage of wheat sharp eyespot has become increasingly severe. In this paper, previous studies on this pathogen, including the disease geographical distribution, pathogen identification, life cycle, symptoms, favourable environmental conditions, effects on wheat yield and control strategy, are reviewed. Such information will be helpful in management of sharp eyespot.  相似文献   
54.
The Red Sea is one of the most biodiverse aquatic ecosystems. Notably, seagrasses possess a crucial ecological significance. Among them are the two taxa Halophila stipulacea (Forsk.) Aschers., and Thalassia hemprichii (Ehrenb. ex Solms) Asch., which were formally ranked together with the genus Enhalus in three separate families. Nevertheless, they have been recently classified as three subfamilies within Hydrocharitaceae. The interest of this study is to explore their metabolic profiles through ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS/MS) analysis in synergism with molecular networking and to assess their chemosystematics relationship. A total of 144 metabolites were annotated, encompassing phenolic acids, flavonoids, terpenoids, and lipids. Furthermore, three new phenolic acids; methoxy benzoic acid-O-sulphate (16), O-caffeoyl-O-hydroxyl dimethoxy benzoyl tartaric acid (26), dimethoxy benzoic acid-O-sulphate (30), a new flavanone glycoside; hexahydroxy-monomethoxy flavanone-O-glucoside (28), and a new steviol glycoside; rebaudioside-O-acetate (96) were tentatively described. Additionally, the evaluation of the antidiabetic potential of both taxa displayed an inherited higher activity of H. stipulaceae in alleviating the oxidative stress and dyslipidemia associated with diabetes. Hence, the current research significantly suggested Halophila, Thalassia, and Enhalus categorization in three different taxonomic ranks based on their intergeneric and interspecific relationship among them and supported the consideration of seagrasses in natural antidiabetic studies.  相似文献   
55.
In this study, purified Eichhornia crassipes dead biomass, coated biomass with ZnO nanoparticles (NPs) and one coated with both ZnO NPs and polyethylenimine (PEI) were successfully fabricated as a bioadsorbent and biodegradent of organic dyes from the textile dye effluent. These ZnO NPs are capable of enhancing the dispersability and adsorption capacity of PEI and the anionic dyes. The surface analyses of Eichhornia crassipes, Eichhornia crassipes/ZnO NPs and Eichhornia crassipes/ZnO NPs/ PEI were characterized by SEM, specific surface area and micropore volume. The effect of three parameters including Eichhornia crassipes concentration, dye concentration and contact time on the color removal percent and degradation percent were evaluated. The results showed that the bleached Eichhornia crassipes was an efficient adsorbent for cationic dyes. Also, the effectiveness of Eichhornia crassipes/ZnO NPs was employed as photocatalytic agent for the degradation of C.I. Direct Red 23 in the presence and absence of UV irradiation. Moreover, Eichhornia crassipes/ZnO NPs/PEI shows a high adsorption capacity toward the anionic dyes C.I. Acid Red 40 and C.I. Reactive Orange 91. It was found that, Eichhornia crassipes/ZnO NPs was completely degraded C.I. Direct Red 23 by >90 % within 90 min of UV irradiation time, whereas in the absence of UV irradiation it required a substantially longer time (120 min) to achieve a similar degradation percent. In addition, Eichhornia crassipes/ZnO NPs/PEI was most effective and show the maximum adsorption capacity for C.I. Reactive Orange 91 and C.I. Acid Red 40 and its efficiency for the color removal percent was 100 % for C.I. Reactive Orange 91 and 95 % for C.I. Acid Red 40 in less than 60 min processing time.  相似文献   
56.
This study assessed the apoptotic process occurring in the hemocytes of the Pacific oyster, Crassostrea gigas, exposed to Alexandrium catenella, a paralytic shellfish toxins (PSTs) producer. Oysters were experimentally exposed during 48 h to the toxic algae. PSTs accumulation, the expression of 12 key apoptotic-related genes, as well as the variation of the number of hemocytes in apoptosis was measured at time intervals during the experiment. Results show a significant increase of the number of hemocytes in apoptosis after 29 h of exposure. Two pro-apoptotic genes (Bax and Bax-like) implicated in the mitochondrial pathway were significantly upregulated at 21 h followed by the overexpression of two caspase executor genes (caspase-3 and caspase-7) at 29 h, suggesting that the intrinsic pathway was activated. No modulation of the expression of genes implicated in the cell signaling Fas-Associated protein with Death Domain (FADD) and initiation-phase (caspase-2) was observed, suggesting that only the extrinsic pathway was not activated. Moreover, the clear time-dependent upregulation of five (Bcl2, BI-1, IAP1, IAP7B and Hsp70) inhibitors of apoptosis-related genes associated with the return to the initial number of hemocytes in apoptosis at 48 h of exposure suggests the involvement of strong regulatory mechanisms of apoptosis occurring in the hemocytes of the Pacific oyster.  相似文献   
57.
Severe late blight epidemics in Tunisia in recent years prompted population studies on the pathogen responsible for this disease, Phythophthora infestans. Characterisation of 165 Tunisian P. infestans isolates collected from 2006 to 2008 was performed for the mating type and mt haplotype, while subsets were analysed for metalaxyl sensitivity (n?=?65), virulence on differential set of 11 R genes of Solanum demissum (n?=?31), aggressiveness on cv. Bintje (n?=?36) and measurement of the radial growth on agar medium at three temperatures (n?=?38). Most isolates from potato and all isolates from tomato had the A1 mating type. The A2 mating type was detected in the north-east and northern areas, but not in the north-west. All the A2 mating type isolates were metalaxyl resistant and seem to be part of a new generation of the P. infestans isolates which are more aggressive, with more complex races, and tolerant to higher temperatures. The increased severity of epidemics during 2006 to 2008 can be attributed to favourable weather conditions during growing seasons, adaptation of new genotypes, widespread phenylamide resistance in potato production regions and most probably incorrect spray programmes. In contrast to the presence of complex pathotypes in two major potato crop regions (north-east and northern areas), the P. infestans population detected in the other regions and in tomato crops was still relatively simple. Compared with the situation in Europe and the American continent, or even compared with neighbouring countries such as Algeria, the genetic changes in Tunisia are still comforting and require strict management decision on late blight control to avoid the spread of new P. infestans populations from Europe or neighbouring countries.  相似文献   
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ABSTRACT: Equine herpesvirus type 1 and 4 (EHV-1 and EHV-4) glycoprotein H (gH) has been hypothesized to play a role in direct fusion of the virus envelope with cellular membranes. To investigate gH's role in infection, an EHV-1 mutant lacking gH was created and the gH genes were exchanged between EHV-1 and EHV-4 to determine if gH affects cellular entry and/or host range. In addition, a serine-aspartic acid-isoleucine (SDI) integrin-binding motif present in EHV-1 gH was mutated as it was presumed important in cell entry mediated by binding to alpha4beta1 or alpha4beta7 integrins. We here document that gH is essential for EHV-1 replication, plays a role in cell-to-cell spread and significantly affects plaque size and growth kinetics. Moreover, we could show that alpha4beta1 and alpha4beta7 integrins are not essential for viral entry of EHV-1 and EHV-4, and that viral entry is not affected in equine cells when the integrins are inaccessible.  相似文献   
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