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91.

Background  

The genus Morus, known as mulberry, is a dioecious and cross-pollinating plant that is the sole food for the domesticated silkworm, Bombyx mori. Traditional methods using morphological traits for classification are largely unsuccessful in establishing the diversity and relationships among different mulberry species because of environmental influence on traits of interest. As a more robust alternative, PCR based marker assays including RAPD and ISSR were employed to study the genetic diversity and interrelationships among twelve domesticated and three wild mulberry species.  相似文献   
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Abstract: We examined beliefs of landowners who hunt and do not hunt regarding chronic wasting disease (CWD) and its management. We mailed surveys to a random sample of 973 Wisconsin, USA, landowners living in the CWD southwest disease eradication zone. Of 613 respondents, 360 (59%) were hunters and 253 (41%) were not hunters. We created multiple item indices to measure respondent beliefs about effects of CWD and its management. Hunters and nonhunters differed on 5 of 6 belief indices. Both groups were, on average, relatively neutral in their trust of the Wisconsin Department of Natural Resources but landowners who did not hunt reported slightly higher trust. Both groups were neutral or slightly agreed that CWD should be managed and they were concerned about deer (Odocoileus spp.) health and the safety of eating venison. Landowners who did not hunt were more likely than those who hunted to agree with these issues but effect sizes indicated these differences were minimal. Landowners who hunted were more concerned than nonhunters about effects of CWD on deer hunting. Cluster analyses indicated most nonhunting landowners were neutral or not concerned about CWD and its management, whereas most hunting landowners were concerned. Our results suggest that managers should use communication campaigns to increase awareness and mitigate concerns about CWD, increase trust and input related to the disease, and inform publics about CWD management strategies.  相似文献   
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Background

Intrathecal (IT) gene transfer is an attractive approach for targeting spinal mechanisms of nociception but the duration of gene expression achieved by reported methods is short (up to two weeks) impairing their utility in the chronic pain setting. The overall goal of this study was to develop IT gene transfer yielding true long-term transgene expression defined as ≥ 3 mo following a single vector administration. We defined "IT" administration as atraumatic injection into the lumbar cerebrospinal fluid (CSF) modeling a lumbar puncture. Our studies focused on recombinant adeno-associated virus (rAAV), one of the most promising vector types for clinical use.

Results

Conventional single stranded rAAV2 vectors performed poorly after IT delivery in rats. Pseudotyping of rAAV with capsids of serotypes 1, 3, and 5 was tested alone or in combination with a modification of the inverted terminal repeat. The former alters vector tropism and the latter allows packaging of self-complementary rAAV (sc-rAAV) vectors. Combining both types of modification led to the identification of sc-rAAV2/l as a vector that performed superiorly in the IT space. IT delivery of 3 × 10e9 sc-rAAV2/l particles per animal led to stable expression of enhanced green fluorescent protein (EGFP) for ≥ 3 mo detectable by Western blotting, quantitative PCR, and in a blinded study by confocal microscopy. Expression was strongest in the cauda equina and the lower sections of the spinal cord and only minimal in the forebrain. Microscopic examination of the SC fixed in situ with intact nerve roots and meninges revealed strong EGFP fluorescence in the nerve roots.

Conclusion

sc-rAAVl mediates stable IT transgene expression for ≥ 3 mo. Our findings support the underlying hypothesis that IT target cells for gene transfer lack the machinery for efficient conversion of the single-stranded rAAV genome into double-stranded DNA and favor uptake of serotype 1 vectors over 2. Experiments presented here will provide a rational basis for utilizing IT rAAV gene transfer in basic and translational studies on chronic pain.  相似文献   
100.

Background  

Internalin A (InlA) is a critical virulence factor which mediates the initiation of Listeria monocytogenes infection by the oral route in permissive hosts. The interaction of InlA with the host cell ligand E-cadherin efficiently stimulates L. monocytogenes entry into human enterocytes, but has only a limited interaction with murine cells.  相似文献   
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