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31.
Rogers J Garcia R Shelledy W Kaplan J Arya A Johnson Z Bergstrom M Novakowski L Nair P Vinson A Newman D Heckman G Cameron J 《Genomics》2006,87(1):30-38
Rhesus macaques (Macaca mulatta) are the most widely used nonhuman primate species in biomedical research. To create new opportunities for genetic and genomic studies using rhesus monkeys, we constructed a genetic linkage map of the rhesus genome. This map consists of 241 microsatellite loci, all previously mapped in the human genome. These polymorphisms were genotyped in five pedigrees of rhesus monkeys totaling 865 animals. The resulting linkage map covers 2048 cM including all 20 rhesus autosomes, with average spacing between markers of 9.3 cM. Average heterozygosity among those markers is 0.73. This linkage map provides new comparative information concerning locus order and interlocus distances in humans and rhesus monkeys. The map will facilitate whole-genome linkage screens to locate quantitative trait loci (QTLs) that influence individual variation in phenotypic traits related to basic primate anatomy, physiology, and behavior, as well as QTLs relevant to risk factors for human disease. 相似文献
32.
Kristofiková Z Kozmiková I Hovorková P Rícný J Zach P Majer E Klaschka J Rípová D 《Neurochemistry international》2008,53(5):118-125
There is evidence that brain lateralization underlying hemispheric specialization can be observed also at biochemical level. However, hemispheric differences in nitric oxide mediator system have not yet been evaluated. The hippocampus and planum temporale are highly asymmetrical regions but the degree of their laterality is altered in demented or psychotic people. In the study, l-glutamate/l-arginine/l-citrulline concentrations, nitric oxide synthase activities/expressions and nitrites/nitrates levels were estimated in autoptic hippocampi. Right/left laterality in endothelial synthase activity and in nitrites/nitrates was observed in controls. Lateral changes were estimated in patients with Alzheimer disease (a marked increase in activities of constitutive synthases and in expression of inducible enzyme in the left side) and schizophrenia (an increase in activities of all enzymes especially in the right side). Significant shifts from positive to negative correlations were found between laterality of some components of nitric oxide pathway and of planum temporale volumetry under pathological conditions. The hippocampal nitric oxide system appears to be globally right/left lateralized, especially via actions of highly asymmetrical endothelial synthase. The results suggest a specific involvement of all synthases in the development of selected diseases and show that lateral analyses are of sufficient sensitivity to reveal subtle links. The volumetric asymmetry of the planum temporale as a marker of handedness is not probably simply linked to brain laterality at biochemical level but reflects alterations due to pathological processes. 相似文献
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Leor Zach David Guez David Last Dianne Daniels Yuval Grober Ouzi Nissim Chen Hoffmann Dvora Nass Alisa Talianski Roberto Spiegelmann Zvi R. Cohen Yael Mardor 《PloS one》2012,7(12)
The current standard of care for newly diagnosed glioblastoma multiforme (GBM) is resection followed by radiotherapy with concomitant and adjuvant temozolomide. Recent studies suggest that nearly half of the patients with early radiological deterioration post treatment do not suffer from tumor recurrence but from pseudoprogression. Similarly, a significant number of patients with brain metastases suffer from radiation necrosis following radiation treatments. Conventional MRI is currently unable to differentiate tumor progression from treatment-induced effects. The ability to clearly differentiate tumor from non-tumoral tissues is crucial for appropriate patient management. Ten patients with primary brain tumors and 10 patients with brain metastases were scanned by delayed contrast extravasation MRI prior to surgery. Enhancement subtraction maps calculated from high resolution MR images acquired up to 75 min after contrast administration were used for obtaining stereotactic biopsies. Histological assessment was then compared with the pre-surgical calculated maps. In addition, the application of our maps for prediction of progression was studied in a small cohort of 13 newly diagnosed GBM patients undergoing standard chemoradiation and followed up to 19.7 months post therapy. The maps showed two primary enhancement populations: the slow population where contrast clearance from the tissue was slower than contrast accumulation and the fast population where clearance was faster than accumulation. Comparison with histology confirmed the fast population to consist of morphologically active tumor and the slow population to consist of non-tumoral tissues. Our maps demonstrated significant correlation with perfusion-weighted MR data acquired simultaneously, although contradicting examples were shown. Preliminary results suggest that early changes in the fast volumes may serve as a predictor for time to progression. These preliminary results suggest that our high resolution MRI-based delayed enhancement subtraction maps may be applied for clear depiction of tumor and non-tumoral tissues in patients with primary brain tumors and patients with brain metastases. 相似文献
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Varying degrees of osteonecrosis result from molar extractions or other oral surgical procedures in rhesus macaques before, during, or after the administration of 6000 rad (the equivalent of human therapeutic dose levels) via either 240 kVp x-ray or cobalt 60 irradiation to the jaw areas subjected to surgery. The effects of various experimental time-dose-wound combinations on the level of impairment of wound-healing, interruption of osteogenesis, and the nature of the response of the irradiation-compromised tissues are covered in this report. 相似文献
37.
Sandra?Viglá?ováEmail authorView authors OrcID profile Old?ich?Nedvěd Peter?Zach Ján?Kulfan Michal?Parák Alois?Honěk Zdenka?Martinková Helen?E.?Roy 《BioControl》2017,62(3):409-421
We evaluated the status of native ladybird assemblages in the presence of the non-native ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae) in three European countries. To achieve this, we assessed the abundance of ladybirds from common host plants in urban areas of Great Britain, Czech Republic and Slovak Republic in 2014. We determined (i) the effects of season, host plant, location, abundance of H. axyridis and aphids on the ladybird species assemblage, (ii) the relationship between ladybird abundance and aphid density, (iii) the relationship between diversity of native ladybird species and the abundance of H. axyridis. There was a non-linear relationship between abundance of ladybirds and abundance of aphids but we found the abundance of other ladybird species was not correlated with H. axyridis. We highlight the value of large-spatial scale studies for revealing patterns in community assemblages and ultimately informing understanding of ecosystem resilience. 相似文献
38.
Zach Kamran Katie Zellner Harry Kyriazes Christine M. Kraus Jean-Baptiste Reynier Jocelyn E. Malamy 《BMC developmental biology》2017,17(1):17
Background
All animals have mechanisms for healing damage to the epithelial sheets that cover the body and line internal cavities. Epithelial wounds heal either by cells crawling over the wound gap, by contraction of a super-cellular actin cable (“purse string”) that surrounds the wound, or some combination of the two mechanisms. Both cell crawling and purse string closure of epithelial wounds are widely observed across vertebrates and invertebrates, suggesting early evolution of these mechanisms. Cnidarians evolved ~600 million years ago and are considered a sister group to the Bilateria. They have been much studied for their tremendous regenerative potential, but epithelial wound healing has not been characterized in detail. Conserved elements of wound healing in bilaterians and cnidarians would suggest an evolutionary origin in a common ancestor. Here we test this idea by characterizing epithelial wound healing in live medusae of Clytia hemisphaerica.Results
We identified cell crawling and purse string-mediated mechanisms of healing in Clytia epithelium that appear highly analogous of those seen in higher animals, suggesting that these mechanisms may have emerged in a common ancestor. Interestingly, we found that epithelial wound healing in Clytia is 75 to >600 times faster than in cultured cells or embryos of other animals previously studied, suggesting that Clytia may provide valuable clues about optimized healing efficiency. Finally, in Clytia, we show that damage to the basement membrane in a wound gap causes a rapid shift between the cell crawling and purse string mechanisms for wound closure. This is consistent with work in other systems showing that cells marginal to a wound choose between a super-cellular actin cable or lamellipodia formation to close wounds, and suggests a mechanism underlying this decision.Conclusions
1. Cell crawling and purse string mechanisms of epithelial wound healing likely evolved before the divergence of Cnidaria from the bilaterian lineage ~ 600mya 2. In Clytia, the choice between cell crawling and purse string mechanisms of wound healing depends on interactions between the epithelial cells and the basement membrane.39.
Smith SK Self J Weiss S Carroll D Braden Z Regnery RL Davidson W Jordan R Hruby DE Damon IK 《Journal of virology》2011,85(17):9176-9187
Smallpox preparedness research has led to development of antiviral therapies for treatment of serious orthopoxvirus infections. Monkeypox virus is an emerging, zoonotic orthopoxvirus which can cause severe and transmissible disease in humans, generating concerns for public health. Monkeypox virus infection results in a systemic, febrile-rash illness closely resembling smallpox. Currently, there are no small-molecule antiviral therapeutics approved to treat orthopoxvirus infections of humans. The prairie dog, using monkeypox virus as a challenge virus, has provided a valuable nonhuman animal model in which monkeypox virus infection closely resembles human systemic orthopoxvirus illness. Here, we assess the efficacy of the antiorthopoxvirus compound ST-246 in prairie dogs against a monkeypox virus challenge of 65 times the 50% lethal dose (LD(50)). Animals were infected intranasally and administered ST-246 for 14 days, beginning on days 0, 3, or after rash onset. Swab and blood samples were collected every 2 days and analyzed for presence of viral DNA by real-time PCR and for viable virus by tissue culture. Seventy-five percent of infected animals that received vehicle alone succumbed to infection. One hundred percent of animals that received ST-246 survived challenge, and animals that received treatment before symptom onset remained largely asymptomatic. Viable virus and viral DNA were undetected or at greatly reduced levels in animals that began treatment on 0 or 3 days postinfection, compared to control animals or animals treated post-rash onset. Animals treated after rash onset manifested illness, but all recovered. Our results indicate that ST-246 can be used therapeutically, following onset of rash illness, to treat systemic orthopoxvirus infections. 相似文献
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