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61.
62.
M A Salih I Harvey S Frankel D J Coupe M Webb H A Cripps 《BMJ (Clinical research ed.)》1991,302(6784):1053-1055
OBJECTIVE--To determine the potential number of cadaver kidney donors by applying defined donor criteria to people dying in hospital. DESIGN--Prospective study of all deaths occurring in 21 hospitals from 1 September 1988 to 31 August 1989. Questionnaires were administered to medical and nursing staff and families of potential donors aged 1-69. SETTING--Acute care hospitals in Gwent, South Glamorgan, Mid Glamorgan, West Glamorgan, Pembrokeshire, and East Dyfed health authorities, serving a population of 2.2 million. MAIN OUTCOME MEASURES--Cause of death, age, ventilation at time of death, diagnosis of brain death, and consideration of consent. RESULTS--Adequate data were available for 9840 of 10,095 hospital deaths (97.5% coverage). 188 patients aged 0-69 were identified as potential organ donors (widest definition), and of these 108 died without being ventilated at the time of death. Tests of brain stem death were formally completed in 57 cases, and organ donation was considered by the families of 47 of these potential donors. 26 patients became organ donors. Patients aged 50-69 with stroke were less likely to be ventilated than those aged less than or equal to 49 (21/96 v 24/34). Families of potential donors aged 20-39 were least likely to give permission. CONCLUSIONS--The supply of donor organs (specifically kidneys) could be increased by altering the management of patients aged 50-69 dying of severe cerebrovascular disease in general medical wards, in particular by increasing the proportion ventilated. The ethics of elective ventilation for the purposes of organ donation require discussion. 相似文献
63.
AM Fietta AM Bardoni R Salvini I Passadore M Morosini L Cavagna V Codullo E Pozzi F Meloni C Montecucco 《Arthritis research & therapy》2007,8(6):R160
Lung fibrosis is a major cause of mortality and morbidity in systemic sclerosis (SSc). However, its pathogenesis still needs
to be elucidated. We examined whether the alteration of certain proteins in bronchoalveolar lavage fluid (BALF) might have
a protective or a causative role in the lung fibrogenesis process. For this purpose we compared the BALF protein profile obtained
from nine SSc patients with lung fibrosis (SScFib+) with that obtained from six SSc patients without pulmonary fibrosis (SScFib-) by two-dimensional gel electrophoresis (2-DE). Only spots and spot-trains that were consistently expressed in a different
way in the two study groups were taken into consideration. In total, 47 spots and spot-trains, corresponding to 30 previously
identified proteins in human BALF, showed no significant variation between SScFib+ patients and SScFib- patients, whereas 24 spots showed a reproducible significant variation in the two study groups. These latter spots corresponded
to 11 proteins or protein fragments, including serum albumin fragments (13 spots), 5 previously recognized proteins (7 spots),
and 4 proteins (3 spots) that had not been previously described in human BALF maps, namely calumenin, cytohesin-2, cystatin
SN, and mitochondrial DNA topoisomerase 1 (mtDNA TOP1). Mass analysis did not determine one protein-spot. The two study groups
revealed a significant difference in BALF protein composition. Whereas levels of glutathione S-transferase P (GSTP), Cu–Zn
superoxide dismutase (SOD) and cystatin SN were downregulated in SScFib+ patients compared with SScFib- patients, we observed a significant upregulation of α1-acid glycoprotein, haptoglobin-α chain, calgranulin (Cal) B, cytohesin-2,
calumenin, and mtDNA TOP1 in SScFib+ patients. Some of these proteins (GSTP, Cu–Zn SOD, and cystatin SN) seem to be involved in mechanisms that protect lungs
against injury or inflammation, whereas others (Cal B, cytohesin-2, and calumenin) seem to be involved in mechanisms that
drive lung fibrogenesis. Even if the 2-DE analysis of BALF did not provide an exhaustive identification of all BALF proteins,
especially those of low molecular mass, it allows the identification of proteins that might have a role in lung fibrogenesis.
Further longitudinal studies on larger cohorts of patients will be necessary to assess their usefulness as predictive markers
of disease. 相似文献
64.
Rens W O'Brien PC Grützner F Clarke O Graphodatskaya D Tsend-Ayush E Trifonov VA Skelton H Wallis MC Johnston S Veyrunes F Graves JA Ferguson-Smith MA 《Genome biology》2007,8(11):R243-21
Background
Sex-determining systems have evolved independently in vertebrates. Placental mammals and marsupials have an XY system, birds have a ZW system. Reptiles and amphibians have different systems, including temperature-dependent sex determination, and XY and ZW systems that differ in origin from birds and placental mammals. Monotremes diverged early in mammalian evolution, just after the mammalian clade diverged from the sauropsid clade. Our previous studies showed that male platypus has five X and five Y chromosomes, no SRY, and DMRT1 on an X chromosome. In order to investigate monotreme sex chromosome evolution, we performed a comparative study of platypus and echidna by chromosome painting and comparative gene mapping.Results
Chromosome painting reveals a meiotic chain of nine sex chromosomes in the male echidna and establishes their order in the chain. Two of those differ from those in the platypus, three of the platypus sex chromosomes differ from those of the echidna and the order of several chromosomes is rearranged. Comparative gene mapping shows that, in addition to bird autosome regions, regions of bird Z chromosomes are homologous to regions in four platypus X chromosomes, that is, X1, X2, X3, X5, and in chromosome Y1.Conclusion
Monotreme sex chromosomes are easiest to explain on the hypothesis that autosomes were added sequentially to the translocation chain, with the final additions after platypus and echidna divergence. Genome sequencing and contig anchoring show no homology yet between platypus and therian Xs; thus, monotremes have a unique XY sex chromosome system that shares some homology with the avian Z. 相似文献65.
Background
It is widely accepted that genetic regulatory systems are 'modular', in that the whole system is made up of smaller 'subsystems' corresponding to specific biological functions. Most attempts to identify modules in genetic regulatory systems have relied on the topology of the underlying network. However, it is the temporal activity (dynamics) of genes and proteins that corresponds to biological functions, and hence it is dynamics that we focus on here for identifying subsystems. 相似文献66.
Ana Paula F Trombone Celio L Silva Luciana P Almeida Rogerio S Rosada Karla M Lima Constance Oliver Maria C Jamur Arlete AM Coelho-Castelo 《Genetic vaccines and therapy》2007,5(1):1-8
Background
Mucopolysaccharidosis type IIIA (MPS IIIA) is the most common of the mucopolysaccharidoses. The disease is caused by a deficiency of the lysosomal enzyme sulphamidase and results in the storage of the glycosaminoglycan (GAG), heparan sulphate. MPS IIIA is characterised by widespread storage and urinary excretion of heparan sulphate, and a progressive and eventually profound neurological course. Gene therapy is one of the few avenues of treatment that hold promise of a sustainable treatment for this disorder.Methods
The murine sulphamidase gene cDNA was cloned into a lentiviral vector and high-titre virus produced. Human MPS IIIA fibroblast cultures were transduced with the sulphamidase vector and analysed using molecular, enzymatic and metabolic assays. High-titre virus was intravenously injected into six 5-week old MPS IIIA mice. Three of these mice were pre-treated with hyperosmotic mannitol. The weight of animals was monitored and GAG content in urine samples was analysed by polyacrylamide gel electrophoresis.Results
Transduction of cultured MPS IIIA fibroblasts with the sulphamidase gene corrected both the enzymatic and metabolic defects. Sulphamidase secreted by gene-corrected cells was able to cross correct untransduced MPS IIIA cells. Urinary GAG was found to be greatly reduced in samples from mice receiving the vector compared to untreated MPS IIIA controls. In addition, the weight of treated mice became progressively normalised over the 6-months post-treatment.Conclusion
Lentiviral vectors appear promising vehicles for the development of gene therapy for MPS IIIA. 相似文献67.
Insects and ungulates co‐occur in grasslands, often feeding on the same plants at the same time and potentially having interactive effects on plant growth. Further, ungulate–insect interactions may differ between native ungulate guilds and domesticated cattle. Despite the prevalence of insects and ungulates in native grasslands, experiments simultaneously manipulating the densities of both these groups are rare. Using large, replicated paddocks, as well as insecticide application, we restricted access to vegetation by each group of herbivores. We also manipulated the species identity of the ungulate assemblage, allowing us to determine whether there are differential effects between native ungulate guilds (bison, elk and deer) and cattle on plant biomass. We found interactive effects of insect and ungulate herbivores on root growth. When insects were suppressed, both native ungulates and cattle caused an approximate doubling of root biomass. However, this stimulatory effect of ungulate grazing was eliminated when insects were also present. In contrast, neither insects nor ungulates had significant effects on shoot biomass at these densities. As a result, the dominant effects of above‐ground herbivory was on belowground plant growth. We suggest the effects of insect and ungulate assemblages on root biomass appear important in regulating primary production in this grassland and may account for some of the contradictory plant responses to ungulate herbivory in the literature. 相似文献
68.
Cliona delitrix is a very destructive coral-excavating sponge in Caribbean coral reef systems, particularly for Montastraea species. Little is known about how these excavating sponges propagate across coral reefs. In this study a hypothesis was tested that coral breakage caused by the bioeroding activity facilitates the asexual propagation of this sponge and in turn favors the spread of the most aggressive sponge genotypes. An allozyme analysis, involving 12 loci systems of 52 sponge individuals from a total of 13 Montastraea heads, found that no two sponges possessed identical multi-locus genotypes. Contrary to the pattern expected for fragmenting species, the incidence of clonality and asexual propagation at the population level was minimal. The lack of correlation between genetic and physical distances for the studied sponges also suggests that population maintenance appears to derive from larval dispersal, with a spatial range of dispersal larger than the average distance between the coral heads (10–102 m). 相似文献
69.
70.
Chemopreventive and renal protective effects for docosahexaenoic acid (DHA): implications of CRP and lipid peroxides 总被引:2,自引:0,他引:2