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71.
Transfer RNATyr (anticodon GA) was isolated from Drosophila melanogaster by means of Sepharose 4B, RPC-5, and polyacrylamide gel electrophoresis. The tRNA was iodinated in vitro with Na125I and hybridized in situ to salivary gland chromosomes from Drosophila. The genes of tRNATyr were localized in eight regions of the genome by autoradiography. Restriction enzyme analysis of genomic DNA indicated that the haploid Drosophila genome codes for about 23 tRNATyr genes. The regions 22F and 85A each contain four to five tRNATyr genes, whereas the regions 28C, 41AB, 42A, 42E, and 56D each contain two to three tRNATyr genes.  相似文献   
72.
Fish are an important model for the pharmacological and toxicological characterization of human pharmaceuticals in drug discovery, drug safety assessment and environmental toxicology. However, do fish respond to pharmaceuticals as humans do? To address this question, we provide a novel quantitative cross-species extrapolation approach (qCSE) based on the hypothesis that similar plasma concentrations of pharmaceuticals cause comparable target-mediated effects in both humans and fish at similar level of biological organization (Read-Across Hypothesis). To validate this hypothesis, the behavioural effects of the anti-depressant drug fluoxetine on the fish model fathead minnow (Pimephales promelas) were used as test case. Fish were exposed for 28 days to a range of measured water concentrations of fluoxetine (0.1, 1.0, 8.0, 16, 32, 64 µg/L) to produce plasma concentrations below, equal and above the range of Human Therapeutic Plasma Concentrations (HTPCs). Fluoxetine and its metabolite, norfluoxetine, were quantified in the plasma of individual fish and linked to behavioural anxiety-related endpoints. The minimum drug plasma concentrations that elicited anxiolytic responses in fish were above the upper value of the HTPC range, whereas no effects were observed at plasma concentrations below the HTPCs. In vivo metabolism of fluoxetine in humans and fish was similar, and displayed bi-phasic concentration-dependent kinetics driven by the auto-inhibitory dynamics and saturation of the enzymes that convert fluoxetine into norfluoxetine. The sensitivity of fish to fluoxetine was not so dissimilar from that of patients affected by general anxiety disorders. These results represent the first direct evidence of measured internal dose response effect of a pharmaceutical in fish, hence validating the Read-Across hypothesis applied to fluoxetine. Overall, this study demonstrates that the qCSE approach, anchored to internal drug concentrations, is a powerful tool to guide the assessment of the sensitivity of fish to pharmaceuticals, and strengthens the translational power of the cross-species extrapolation.  相似文献   
73.
Astroviruses are becoming a growing concern in veterinary and public health. To date there are no registered vaccines against astrovirus-induced disease, mostly due to the difficulty to cultivate astroviruses to high titer for vaccine development using conventional techniques. As means to circumvent this drawback, we have developed stably transfected mink fetal cells and BHK21 cells constitutively expressing the full-length and truncated capsid proteins of two distinct genotypes of mink astrovirus. Protein expression in these stably transfected cells was demonstrated by strong signals as evaluated by in-situ PLA and IFA, and confirmed by Western blotting. The recombinant full-length and truncated proteins induced a high level of antibodies in mink, evaluated by ELISA, demonstrating their immunogenicity. In a challenge experiment in mink, a reduction in presentation clinical signs and virus shedding was observed in mink kits born from immunized females. The gene integration and protein expression were sustained through cell passage, showing that the used approach is robust and reliable for expression of functional capsid proteins for vaccine and diagnostic applications.  相似文献   
74.
This article discusses an emerging mortuary practice: the establishment of columbaria in sport stadiums, and surreptitious ash dispersal on their playing fields. Focusing on a Spanish‐Basque fan community, I explore ethnographically the beliefs, identifications, and experiences that allow fans to think their insertion, once dead, into a football stadium. Contrary to the view that considers the mobility of ash remains as a result of increasing individual choice, and decreasing concern with space and place, ash dispersal in stadiums shows that, while the act is an individual decision, there remains a great concern with place, and with the act's consequences for the community. Stadiums are becoming final resting places precisely because of their pivotal social, communal, and emotional relevance. In sum, the article argues that individualized approaches to death and dying take collective forms.  相似文献   
75.
Genetic diversity of a Botrytis cinerea cryptic species complex in Hungary   总被引:1,自引:0,他引:1  
Botrytis cinerea has been described as a species complex containing two cryptic species, referred to as groups I and II. The first B. cinerea group I strains outside of Western Europe were collected in Hungary in 2008 from strawberry and rape plants. Sympatric B. cinerea cryptic species were analyzed using a population genetic approach and phenotypic markers. Statistically significant, but moderate population differentiation was found between the two groups in Hungary. Group I was originally typified by the lack of the transposable elements Boty and Flipper. However, all the Hungarian group I isolates carried the Boty element and one isolate additionally contained Flipper, indicating a much wider genetic variation than previously believed. Vegetative compatibility analyses showed that twelve of the thirteen B. cinerea group I isolates studied belonged to a unique vegetative compatibility group (VCG), but VCGs overlapped between groups. Phenotypic markers such as fenhexamid resistance or asexual spore size were found unsuitable to differentiate between the cryptic species. The results did not confirm the complete separation of the two cryptic species, previously determined with genealogical concordance of the phylogenetic species recognition using multiple gene sequences, and suggest instead the possibility of information exchange between them.  相似文献   
76.
Aleutian mink disease virus (AMDV) causes severe disease in farmed mink (Neovison vison) worldwide. In Denmark, AMDV in farmed mink has been confined to the northern part of the mainland since 2002. From 1998 to 2009, samples from 396 free-ranging mink were collected from mainland Denmark, and a low AMDV antibody prevalence (3% of 296) was found using countercurrent immune electrophoresis. However, on the island of Bornholm in the Baltic Sea, a high prevalence (45% of 142 mink) was detected in the free-ranging mink. Aleutian mink disease virus was detected by polymerase chain reaction in 32 of 49 antibody-positive free-ranging mink on Bornholm, but not in mink collected from other parts of Denmark. Sequence analysis of 370 base pairs of the nonstructural gene of the AMDV of 17 samples revealed two clusters with closest similarity to Swedish AMDV strains.  相似文献   
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79.

Rationale

Acute myocardial infarction (AMI) followed by ventricular remodeling is the major cause of congestive heart failure and death in western world countries.

Objective

Of relevance are reports showing that infusion of apoptotic leucocytes or anti-lymphocyte serum after AMI reduces myocardial necrosis and preserves cardiac function. In order to corroborate this therapeutic mechanism, the utilization of an immunosuppressive agent with a comparable mechanism, such as anti-thymocyte globulin (ATG) was evaluated in this study.

Methods and Results

AMI was induced in rats by ligation of the left anterior descending artery. Initially after the onset of ischemia, rabbit ATG (10 mg/rat) was injected intravenously. In vitro and in vivo experiments showed that ATG induced a pronounced release of pro-angiogenic and chemotactic factors. Moreover, paracrine factors released from ATG co-incubated cell cultures conferred a down-regulation of p53 in cardiac myocytes. Rats that were injected with ATG evidenced higher numbers of CD68+ macrophages in the ischemic myocardium. Animals injected with ATG evidenced less myocardial necrosis, showed a significant reduction of infarct dimension and an improvement of post-AMI remodeling after six weeks (infarct dimension 24.9% vs. 11.4%, p<0.01). Moreover, a higher vessel density in the peri-infarct region indicated a better collateralization in rats that were injected with ATG.

Conclusions

These data indicate that ATG, a therapeutic agent successfully applied in clinical transplant immunology, triggered cardioprotective effects after AMI that salvaged ischemic myocardium by down-regulation of p53. This might have raised the resistance against apoptotic cell death during ischemia. The combination of these mechanisms seems to be causative for improved cardiac function and less ventricular remodeling after experimental AMI.  相似文献   
80.
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