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991.
Severe acute pancreatitis (SAP) is a common disease with a poor prognosis. Heart failure is one cause of SAP patient death.
Intermedin (IMD) is a potent endogenous cardio-protective substance. Administration of exogenous IMD showed beneficial effects
in cardiovascular diseases. The aim of this study was to investigate the myocardial damage in SAP and to determine the therapeutic
potential of IMD for SAP. Using an SAP rat model, we examined endogenous IMD expression following SAP induction, and determined
the effect of IMD on myocardial function, histological morphology, apoptosis-related gene expression, and prognosis. Our results
indicated that the cardiac function and histological structure were significantly disrupted in SAP rats. Infusion of exogenous
IMD significantly preserved cardiac function and ameliorated myocardial damage. Terminal deoxynucleotidyl transferase-mediated
dUTP nick end labeling (TUNEL) revealed that myocardial apoptosis was extensively present in SAP rats, and IMD infusion led
to increased expression of the prosurvival factor Bcl-2, but decreased pro-apoptotic factors Bax and caspase-3. In addition,
IMD infusion also reversed the change of IMD receptor systems in SAP rat heart tissue. Furthermore, we found that IMD infusion
greatly decreased mortality of SAP rats. In conclusion, administration of SAP produced therapeutic effects in SAP through
modulating apoptotic and pro-survival gene expression, inhibiting myocardial apoptosis, preserving cardiac function, and a
useful therapeutic agent for SAP, and provides us an insight for a clinical trial of IMD for treating human severe acute pancreatitis. 相似文献
992.
Zhang Y Xu P Lu C Kuang Y Zhang X Cao D Li C Chang Y Hou N Li H Wang S Sun X 《Marine biotechnology (New York, N.Y.)》2011,13(3):376-392
A genetic linkage map of common carp (Cyprinus carpio L.) was constructed using Type I and Type II microsatellite markers and a pseudo-testcross mapping strategy. The microsatellite markers were isolated from microsatellite-enriched genomic libraries and tested for their segregation in a full-sib mapping panel containing 92 individuals. A total of 161 microsatellite loci were mapped into 54 linkage groups. The total lengths of the female, male and consensus maps were 2,000, 946, and 1,852?cM, with an average marker spacing of approximately 13, 7, and 11?cM, respectively. Muscle fiber-related traits, including muscle fiber cross-section area and muscle fiber density, were mapped to the genetic map. Three QTLs for muscle fiber cross-section area and two QTLs for muscle fiber density were identified when considering both significant and suggestive QTL effects. The QTLs with largest effects for muscle fiber cross-section area and muscle fiber density were 21.9% and 18.9%, and they were located in LG3, respectively. 相似文献
993.
Tian L Cao C He L Li M Zhang L Zhang L Liu H Liu N 《International journal of biological sciences》2011,7(6):902-911
Five BC? lines and 16 house fly mass-cross homozygous lines were generated from crosses of the pyrethroid resistant ALHF (wild-type) and susceptible aabys (bearing recessive morphological markers on each of five autosomes) strains. Each of the resulting homozygous lines had different combinations of autosomes from the resistant ALHF strain. Levels of resistance to permethrin were measured for each line to determine the autosomal linkage, interaction and, possibly, regulation in pyrethroid resistance of house flies. Results indicated that factors on autosome 4 are not involved in the development of resistance in house flies, while factors on autosomes 1, 2, 3 and 5 play important roles in pyrethroid resistance. The sodium channel gene has been mapped on autosome 3 and multiple cytochrome P450 genes overexpressed in resistant ALHF house flies have been genetically mapped on autosome 5, suggesting that P450 mediated detoxification and sodium channel-mediated target site insensitivity located on autosomes 3 and 5, respectively, are major factors related to resistance development in house flies. However, neither the factors on autosome 3 or 5 alone, nor the factors from both autosomes 3 and 5 combined could confer high levels of resistance to pyrethroid. In addition, strong synergistic effects on resistance was obtained when autosomes 1 and 2 interact with autosome 3 and/or 5, suggesting that the trans factors on autosomes 1 and 2 may interact with factors on autosomes 3 and 5, therefore, playing regulatory roles in the development of sodium channel insensitivity- and P450 detoxification-mediated resistance. 相似文献
994.
Environmental exposure, genetic modification, and aging are considered risky for Parkinson's disease (PD). How these risk factors cooperate to induce progressive neurodegeneration in PD remains largely unknown. Paraquat is an herbicide commonly used for weed and grass control. Exposure to paraquat is associated with the increased incidence of PD. In contrast to familial PD, most sporadic PD cases do not have genetic mutation, but may suffer from partial dysfunction of neuron-protective genes as aging. Using conditional transgenic RNAi, we showed that temporal silencing of PINK1 expression in adult mice increased striatal dopamine, the phenotype that could not be induced by constitutive gene silencing. Moreover, early exposure to paraquat sensitized dopaminergic neurons to subsequent silencing of PINK1 gene expression, leading to a significant loss of dopaminergic neurons. Our findings suggest a novel pathogenesis of PD: exposure to environmental toxicants early in the life reduces the threshold of developing PD and partial dysfunction of neuron-protective genes later in the life initiates a process of progressive neurodegeneration to cross the reduced threshold of disease onset. 相似文献
995.
Distributed sensor activation algorithm for target tracking with binary sensor networks 总被引:1,自引:0,他引:1
Target tracking with wireless sensor networks (WSNs) has been a hot research topic recently. Many works have been done to
improve the algorithms for localization and prediction of a moving target with smart sensors. However, the results are frequently
difficult to implement because of hardware limitations. In this paper, we propose a practical distributed sensor activation
algorithm (DSA2) that enables reliable tracking with the simplest binary-detection sensors. In this algorithm, all sensors in the field are
activated with a probability to detect targets or sleep to save energy, the schedule of which depends on their neighbor sensors’
behaviors. Extensive simulations are also shown to demonstrate the effectiveness of the proposed algorithm. Great improvement
in terms of energy-quality tradeoff and excellent robustness of the algorithm are also emphasized in the simulations. 相似文献
996.
Sperm need to mature in the epididymis to become capable of fertilization. To understand the molecular mechanisms of mouse sperm maturation, we conducted a proteomic analysis using saturation dye labeling to identify proteins of caput and cauda epididymal sperm that exhibited differences in amounts or positions on two-dimensional gels. Of eight caput epididymal sperm-differential proteins, three were molecular chaperones and three were structural proteins. Of nine cauda epididymal sperm-differential proteins, six were enzymes of energy metabolism. To validate these proteins as markers of epididymal maturation, immunoblotting and immunofluorescence analyses were performed. During epididymal transit, heat shock protein 2 was eliminated with the cytoplasmic droplet and smooth muscle γ-actin exhibited reduced fluorescence from the anterior acrosome while the signal intensity of aldolase A increased, especially in the principal piece. Besides these changes, we observed protein spots, such as glutathione S-transferase mu 5 and the E2 component of pyruvate dehydrogenase complex, shifting to more basic isoelectric points, suggesting post-translational changes such dephosphorylation occur during epididymal maturation. We conclude that most caput epididymal sperm-differential proteins contribute to the functional modification of sperm structures and that many cauda epididymal sperm-differential proteins are involved in ATP production that promotes sperm functions such as motility. 相似文献
997.
Important advances have been made in the immunodiagnosis of tuberculosis (TB) based on the detection of Mycobacterium tuberculosis (MTB)-specific T cells. However, the sensitivity and specificity of the immunological approach are relatively low because there are no specific markers for antigen-specific Th cells, and some of the Th cells that do not produce cytokines can be overlooked using this approach. In this study, we found that MTB-specific peptides of ESAT-6/CFP-10 can stimulate the expression of CD40L specifically in CD4(+) T cells but not other cells from pleural fluid cells (PFCs) in patients with tuberculous pleurisy (TBP). CD4(+)CD40L(+) but not CD4(+)CD40L(-) T cells express IFN-γ, IL-2, TNF-α, IL-17 or IL-22 after stimulation with MTB-specific peptides. In addition, CD4(+)CD40L(+) T cells were found to be mostly polyfunctional T cells that simultaneously produce IFN-γ, IL-2 and TNF-α and display an effector or effector memory phenotype (CD45RA(-)CD45RO(+)CCR7(-)CD62L(-)ICOS(-)). To determine the specificity of CD4(+)CD40L(+) T cells, we incubated PFCs with ESTA-6/CFP-10 peptides and sorted live CD4(+)CD40L(+) and CD4(+)CD40L(-) T cells by flow cytometry. We further demonstrated that sorted CD4(+)CD40L(+), but not CD4(+)CD40L(-) fractions, principally produced IFN-γ, IL-2, TNF-α, IL-17 and IL-22 following restimulation with ESTA-6/CFP-10 peptides. Taken together, our data indicate that the expression of CD40L on MTB-specific CD4(+) T cells could be a good marker for the evaluation and isolation of MTB-specific Th cells and might also be useful in the diagnosis of TB. 相似文献
998.
Background
It is a widespread belief in Asian countries that mung bean soup (MBS) may afford a protective effect against heat stress. Lack of evidence supports MBS conferring a benefit in addition to water.Results
Here we show that vitexin and isovitexin are the major antioxidant components in mungbean (more than 96% of them existing in the bean seed coat), and both of them could be absorbed via gavage into rat plasma. In the plasma of rats fed with mungbean coat extract before or after exposure to heat stress, the levels of malonaldehyde and activities of lactate dehydrogenase and nitric oxide synthase were remarkably reduced; the levels of total antioxidant capacity and glutathione (a quantitative assessment of oxidative stress) were significantly enhanced.Conclusions
Our results demonstrate that MBS can play additional roles to prevent heat stress injury. Characterization of the mechanisms underlying mungbean beneficial effects should help in the design of diet therapy strategies to alleviate heat stress, as well as provide reference for searching natural medicines against oxidative stress induced diseases. 相似文献999.
Qi Shi Cao Chen Xiao-Nan Song Chen Gao Chan Tian Wei Zhou Xu-Hua Song Lai-Shun Yao Jun Han Xiao-Ping Dong 《朊病毒》2011,5(2):117-120
Genetic Creutzfeldt-Jakob disease (gCJD) is caused by a range of mutations in the prion protein gene (PRNP) and account for approximately 10–15% of overall human prion diseases worldwide. They are different with disease onset, disease duration, clinical signs and diagnostic findings. Here we reported a 71 year-old female with an E196K mutation in one PRNP allele, while the codon 129 was a methionine homozygous genotype. The patient started with non-specific symptoms, but displayed rapidly progressive disturbances of speech, memory, cognitive and physical movement. No periodic activity was recorded at electroencephalography (EEG) during the entire disease course. Retrospective investigation of her family members did not reveal similar neurological disorders. Total clinical course was about seven months.Key words: Creutzfeldt-Jakob disease, PRNP, E196K 相似文献
1000.