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121.
Brain death (BD) causes cardiac dysfunction in organ donors, attributable to the catecholamine storm that occurs with raised intracerebral pressure (ICP). However the direct contribution of the spinal sympathetics has not been well described. We examined the effect of total spinal anesthesia (TSA) on cardiac function in a large animal model of BD. Eighteen pigs were allocated to 3 experimental groups: Group?1, the saline-treated control group; Group?2, TSA administered prior to BD; and Group?3, TSA administered 30?min after BD. Inflation of an intracerebral balloon-tipped catheter was used to induce BD. Ventricular function was assessed using a pressure-volume loop catheter and magnetic resonance imaging. Serum catecholamine levels were assessed with high performance liquid chromatography. Inflation of the intracerebral balloon-tipped catheter was associated with a dramatic rise in heart rate and blood pressure, along with increased concentrations of serum epinephrine and norepinephrine. This phenomenon was not observed in Group 2. In Group 1, there was a significant decline in contractility, whereas groups 2 and?3 saw no change. Group 2 had greater contractile reserve than groups 1 and 3. Our data demonstrate the central role of spinal sympathetics in the hemodynamic response to raised ICP. Further work is required to determine the utility of TSA in reversing cardiac dysfunction in BD donors.  相似文献   
122.
Sutorius is described as a new genus of Boletaceae to accommodate Boletus robustus originally named illegitimately by C.C. Frost from eastern North America. The legitimate name, Boletus eximius, provided by C.H. Peck, has been used since for a dark purple to chocolate brown bolete with finely scaly stipe and reddish brown spore deposit. This iconic taxon has been documented on five continents. Despite the straightforward species identification from morphology, the interpretation of stipe macro-morphology and spore color has led to equivocal generic placement. Phylogenetic analyses of genes encoding large subunit rRNA and translation elongation factor 1α confirm Sutorius as a unique generic lineage in the Boletaceae. Two species are recognized based on multiple accessions: S. eximius, represented by collections from North America, Costa Rica, Guyana, Indonesia and Japan (molecular data are lacking for only the Guyanan and Japanese material); and S. australiensis, represented by material from Queensland, Australia. Additional collections from Zambia and Thailand represent independent lineages, but sampling is insufficient to describe new species for these entities.  相似文献   
123.
Philopatry and sex-biased dispersal have a strong influence on population genetic structure, so the study of species dispersal patterns and evolutionary mechanisms shaping them are of great interest. Particularly nongregarious mammalian species present an underexplored field of study: despite their lower levels of sociality compared to group-living species, interactions among individuals do occur, providing opportunities for cryptic kin selection. Among the least gregarious primates are orang-utans (genus: Pongo), in which preferential associations among females have nevertheless been observed, but for which the presence of kin structures was so far unresolved because of the equivocal results of previous genetic studies. To clarify relatedness and dispersal patterns in orang-utans, we examined the largest longitudinal set of individuals with combined genetic, spatial and behavioural data. We found that males had significantly higher mitochondrial DNA (mtDNA) variation and more unique haplotypes, thus underscoring their different maternal ancestries compared to females. Moreover, pedigree reconstruction based on 24 highly polymorphic microsatellite markers and mtDNA haplotypes demonstrated the presence of three matrilineal clusters of generally highly related females with substantially overlapping ranges. In orang-utans and possibly other nongregarious species, comparing average biparental relatedness (r) of males and females to infer sex-biased dispersal is extremely problematic. This is because the opportunistic sampling regime frequently employed in nongregarious species, combined with overlapping space use of distinct matrilineal clusters, leads to a strong downward bias when mtDNA lineage membership is ignored. Thus, in nongregarious species, correct inferences of dispersal can only be achieved by combining several genetic approaches with detailed spatial information.  相似文献   
124.
Obesity has become a major global health problem. Recently, attention has focused on the benefits of fermentable carbohydrates on modulating metabolism. Here, we take a system approach to investigate the physiological effects of supplementation with oligofructose-enriched inulin (In). We hypothesize that supplementation with this fermentable carbohydrate will not only lead to changes in body weight and composition, but also to modulation in neuronal activation in the hypothalamus. Male C57BL/6 mice were maintained on a normal chow diet (control) or a high fat (HF) diet supplemented with either oligofructose-enriched In or corn starch (Cs) for 9 weeks. Compared to HF+Cs diet, In supplementation led to significant reduction in average daily weight gain (mean ± s.e.m.: 0.19 ± 0.01 g vs. 0.26 ± 0.02 g, P < 0.01), total body adiposity (24.9 ± 1.2% vs. 30.7 ± 1.4%, P < 0.01), and lowered liver fat content (11.7 ± 1.7% vs. 23.8 ± 3.4%, P < 0.01). Significant changes were also observed in fecal bacterial distribution, with increases in both Bifidobacteria and Lactobacillius and a significant increase in short chain fatty acids (SCFA). Using manganese-enhanced MRI (MEMRI), we observed a significant increase in neuronal activation within the arcuate nucleus (ARC) of animals that received In supplementation compared to those fed HF+Cs diet. In conclusion, we have demonstrated for the first time, in the same animal, a wide range of beneficial metabolic effects following supplementation of a HF diet with oligofructose-enriched In, as well as significant changes in hypothalamic neuronal activity.  相似文献   
125.
126.
Bornean orang-utans experienced a major demographic decline and local extirpations during the Pleistocene and Holocene due to climate change, the arrival of modern humans, of farmers and recent commercially-driven habitat loss and fragmentation. The recent loss of habitat and its dramatic fragmentation has affected the patterns of genetic variability and differentiation among the remaining populations and increased the extinction risk of the most isolated ones. However, the contribution of recent demographic events to such genetic patterns is still not fully clear. Indeed, it can be difficult to separate the effects of recent anthropogenic fragmentation from the genetic signature of prehistoric demographic events. Here, we investigated the genetic structure and population size dynamics of orang-utans from different sites. Altogether 126 individuals were analyzed and a full-likelihood Bayesian approach was applied. All sites exhibited clear signals of population decline. Population structure is known to generate spurious bottleneck signals and we found that it does indeed contribute to the signals observed. However, population structure alone does not easily explain the observed patterns. The dating of the population decline varied across sites but was always within the 200–2000 years period. This suggests that in some sites at least, orang-utan populations were affected by demographic events that started before the recent anthropogenic effects that occurred in Borneo. These results do not mean that the recent forest exploitation did not leave its genetic mark on orang-utans but suggests that the genetic pool of orang-utans is also impacted by more ancient events. While we cannot identify the main cause for this decline, our results suggests that the decline may be related to the arrival of the first farmers or climatic events, and that more theoretical work is needed to understand how multiple demographic events impact the genome of species and how we can assess their relative contributions.  相似文献   
127.

Background

Chronic constipation (CC) is a common condition but its concurrent conditions are not well characterized. We measured the prevalence and risk of developing 15 pre–specified concurrent conditions in patients with CC.

Methods

Retrospective cohort study using the Medicaid database of California, utilizing ICD-9 codes for detection of cases (CC), controls (patients with GERD) and concurrent conditions. Study period was 01/01/1995 to 06/30/2005. Index date was the date 3 months before the first physician visit for CC. Pre-index time (12 months) was compared to post-index time (12 months) to assess the association of every concurrent condition within each cohort. To account for ascertainment bias, an adjusted odds ratio was calculated by comparing the odds ratio for every concurrent condition in the CC cohort to that in the GERD cohort.

Results

147,595 patients with CC (mean age 54.2 years; 69.7% women; 36.2% white) and 142,086 patients with GERD (mean age 56.3 years; 65.3% women; 41.6% white) were evaluated. The most prevalent concurrent conditions with CC were hemorrhoids (7.6%), diverticular disease (5.9%), ano–rectal hemorrhage (4.7%), irritable bowel syndrome (3.5%) and fecal impaction (2%). When adjusted for ascertainment bias, the most notable associations with CC were Hirschsprung''s disease, fecal impaction and ano-rectal conditions such as fissure, fistula, hemorrhage and ulcers.

Conclusion

Chronic constipation is associated with several concurrent conditions of variable risk and prevalence. To reduce the overall burden of CC, these concurrent conditions need to be addressed.  相似文献   
128.
129.
A new analytical method using gas chromatography with mass spectrometry (GC-MS) for the quantitative determination of lufenuron, a benzoylphenylurea (BPU) class of insecticide, from wheat flour has been developed and applied for time-dependent residue monitoring in treated wheat flour. The analyte was extracted from wheat flour by a single step solid-liquid extraction by using ethyl acetate and subsequently cleaned up using the Primary Secondary Amine as a sorbent prior to GC-MS analysis. The present method provides sufficient sensitivity as reflected by the values of limit of detection (LOD) and limit of quantification (LOQ), 5 ng/mL (S/N approximately 3) and 50 ng/mL (the lowest validation point on the calibration curve), respectively. The calibration curve showed an excellent linearity in the concentration range of 50-1000 ng/mL (r2=0.998). The average recovery for spiked samples at three concentrations (150, 300, and 450 ng/g) was 98.23+/-2.52% R.S.D. The method was applied for the determination of lufenuron residues in treated wheat flour samples. Simultaneous determination of bio-efficacy of lufenuron residues was also carried out against the red flour beetle, Tribolium castaneum to correlate the actual residual effect of lufenuron as detected by the analytical method, over a period of 3 months. The findings revealed that the residual concentration of lufenuron were neither uniform nor in descending order over a period of 3 months in wheat flour, possibly because of an uneven dispersal in the treated wheat which was subsequently milled into flour, as confirmed by GC-MS analysis. However, the residues of lufenuron were sufficient to produce 100% mortality of T. castaneum larvae up to 3 months. The results have been discussed in view of the potential of lufenuron as a candidate molecule for the control of stored product pests.  相似文献   
130.
The Houses That Matsutake Built. In the mountains of northwest Yunnan, China, a valuable mushroom, matsutake or song rong (Tricholoma matsutake) was commodified in the 1980s. Since that time, it has been exported in large quantities to Japan. The sale of matsutake now contributes more to the income of Shangri-la County (Diqing Autonomous Tibetan Prefecture) than any other crop, including timber and livestock. During the 1980s and 1990s, villagers in this remote region used their mushroom earnings to build spacious, beautiful new houses in the traditional local (Kham) style, and in some cases to buy motor vehicles or open businesses. In villages with access to productive matsutake habitat, virtually every household was able to build a new house; entire villages were transformed. During the 1990s, several villages developed locally based management regimes to enhance production and to address the problems and conflicts that arose from the harvest of such a valuable product. More recently, government agencies and NGOs have played a highly visible role in promoting “sustainable” harvest policies. The implications of their involvement are briefly examined and the future of matsutake harvest in Yunnan is discussed.  相似文献   
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