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This review re-evaluates the use of immunological probes to map enkephalinergic, dynorphinergic, and endorphinergic circuits in the CNS of lobe-finned fishes, ray-finned fishes, and cartilaginous fishes in light of the characterization of proenkephalin, prodynorphin, and POMC sequences from representatives of these groups of fish over the past 20 years. The use of α-MSH specific antisera is a reliable method for detecting POMC immunopositive cell bodies and fibers. Since α-MSH and β-endorphin are co-localized in the same neurons, these studies also reveal the distribution of endorphinergic networks. Met-enkephalin specific antisera can be used to detect enkephalinergic circuits in the CNS of gnathostomes because of the ubiquitous presence of this pentapeptide in the proenkephalin sequences of gnathostomes. However, the use of leu-enkephalin specific antisera to detect enkephalinergic networks is more problematic. While this immunological probe is appropriate for analyzing enkephalinergic networks in mammals and perhaps teleosts, for the lungfishes and cartilaginous fishes this probe is more likely able to detect dynorphinergic circuits. In this regard, there is a need to re-examine dynorphinergic networks in non-mammalian gnathostomes by using species specific antisera directed against dynorphin end-products.  相似文献   

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Overlapping cloned cDNAs representing the entire sequence of the rat fatty acid synthase mRNA have been isolated from a cDNA library and sequenced. Authenticity of the cDNA clones was supported by hybridization to fatty acid synthase mRNA and by amino-terminal sequencing of 39 fatty acid synthase CNBr fragments. The full-length fatty acid synthase mRNA is 9156 nucleotides long and includes an 84-nucleotide 5' noncoding region, a 7515-nucleotide coding sequence, and a 1537-nucleotide 3' noncoding region; a second mRNA species containing a shortened 3' noncoding sequence is also transcribed in the rat. The encoded fatty acid synthase subunit contains 2505 amino acids and has a molecular weight of 272,340. Active sites and substrate binding sites were located within the sequence, thus establishing the order of domains on the multifunctional animal fatty acid synthase as condensing enzyme-transferase-dehydrase-enoyl reductase-ketoreductase-acyl carrier protein-thioesterase.  相似文献   

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Little was known about the development of the gastrointestinal (GI) tract microbiota, until recently, because of difficulties in obtaining sufficient sequence information from enough people or time points. Now, with decreased costs of DNA sequencing and improved bioinformatic tools, we can compare GI tract bacterial communities among individuals, of all ages from infancy to adulthood. Some key recent findings are that the initial bacterial community, even in the GI tract, depends strongly on delivery mode; that the process of early development of the microbiota is highly unstable and idiosyncratic; that the microbiota differs considerably among children from different countries; and that older adults have substantially different GI tract communities than younger adults, indicating that the GI tract microbiota can change throughout life. We relate these observations to different models of evolution including the evolution of senescence and suggest that probiotics be selected based on patient age. Studies of the microbiota in older people might tell us which probiotics could increase longevity. Drug metabolism varies among individuals with different microbial communities, so age- and region-specific clinical trials are required to ensure safety and efficacy.  相似文献   

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The human immunodeficiency virus envelope gene was expressed in insect cells by using a Baculovirus expression vector. The protein has an apparent molecular mass of 160 kDa, appears on the surface of infected insect cells, and does not appear to be cleaved to glycoproteins gp120 and gp41. Goats immunized with the 160-kDa protein have high titers of antibody that neutralizes virus infection as measured by viral gene expression or cell cytolysis. In addition, immune sera can block fusion of human immunodeficiency virus-infected cells in culture. Both neutralization and fusion-blocking activities are bound to and eluted from immobilized gp120.  相似文献   

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We report the analyses of recently cloned restriction fragments of the natural ovalbumin gene that overlap in part with previously cloned DNA fragments but extend further into the flanking sequences of the gene. These clones now permit us to identify the DNA sequence that codes for the 5' end of ovalbumin mRNA. Based on these and previous results, the molecular organization of the entire ovalbumin gene was established. The entire gene is composed of eight structural DNA sequences separated by seven intervening sequences that are not present in the mature mRNA. In addition, an ovalbumin gene clone has been obtained from a chicken gene library. Analysis of DNA isolated from this particular clone by molecular hybridization and electron microscopic mapping revealed that it contains the entire ovalbumin gene a single segment of DNA and its structure was consistent with that predicted from our physical map constructed from individually cloned fragments of the gene.  相似文献   

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The complete nucleotide sequence (119,707 bp) of the black pine (Pinus thunbergii) chloroplast genome has been determined. It contains 4 rRNA genes and 32 tRNA genes. To our knowledge, the tRNAPro (GGG) gene has not been found in any other chloroplast genome analyzed. Sixty-one genes encoding proteins and 11 conserved open reading frames are also found. Extensive rearrangements are apparent in the chloroplast genome relative to those of other land plants. The most striking feature is the loss of all 11 functional genes (ndh genes) for subunits of a putative NADH dehydrogenase that are found in the chloroplast genomes of angiosperms and a bryophyte. Four ndh genes were completely lost and the other 7 genes remain as obvious pseudogenes. This unexpected finding raises the possibility that all ndh genes have been transferred to the nucleus or that an NADH dehydrogenase is not essential in black pine chloroplasts.  相似文献   

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Bacteria are sparsely distributed in the stomach due to the gastric microbicidal barrier. Several innate defenses (low pH, migrating motor complex and the entero‐salivary circulation of nitrate) as well as external factors (diet, Helicobacter pylori infection, proton pump inhibitors, antibiotics and stomach diseases) have been shown to influence significantly the microbiota composition in the stomach. In recent years new culture‐independent technologies have allowed the investigation of the cross talk that occurs between hosts and stomach‐associated microflora, which helps us to understand the role of gastric bacterial flora in the gastrointestinal microbiological system, both in physiological and pathological conditions. Here, we reviewed the literatures related to this topic and set the stage for future developments of the field.  相似文献   

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Xu  Huixuan  Yu  Haiyan  Zheng  Fengping  Zhang  Cantong  Cai  Wanxia  Zhang  Xinzhou  Tang  Donge  Dai  Yong 《Clinical rheumatology》2022,41(11):3513-3524
Clinical Rheumatology - This study aims to provide a new perspective of determining the pathophysiology of chronic hepatitis B (CHB) development by analyzing the gene regulatory network in CHB...  相似文献   

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PURPOSE: Recent end point trials of lipid-lowering drugs have shown that patients at very high-risk for coronary disease benefit from treatments that lowers low density lipoprotein cholesterol (LDL cholesterol) plasma levels< or =70 mg/dl and that patients with at least 2 risk factors benefit from LDL cholesterol levels< or =100 mg/dl. Epidemiologic studies have shown that the concentration of high density lipoprotein cholesterol (HDL cholesterol) is a strong, independent, inverse predictor of coronary disease risk. Innovative pharmacological approaches to raise low HDL cholesterol levels are currently of considerable interest, especially for patients with type 2 diabetes or metabolic syndrome. RESULTS: Rosuvastatin has shown superior efficacy in lowering LDL cholesterol, although evidence of clinical benefit is actually lacking. Ezetimibe is a lipid-lowering drug that inhibits absorption of dietary and biliary cholesterol. Its co-administration with statin has given very interesting results. Niacin is the most effective of currently available options for raising HDL cholesterol, although tolerability can be an issue, with serious side effects such as loss of glucose control and liver toxicity. Flushing may occur in 80% of treated patients. Two CETP inhibitors have shown therapeutical efficacy to raise HDL cholesterol, but clinical benefit remains uncertain.  相似文献   

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Sequencing and comparative analyses of genomes from multiple vertebrates are providing insights about the genetic basis for biological diversity. To date, these efforts largely have focused on eutherian mammals, chicken, and fish. In this article, we describe the generation and study of genomic sequences from noneutherian mammals, a group of species occupying unusual phylogenetic positions. A large sequence data set (totaling >5 Mb) was generated for the same orthologous region in three marsupial (North American opossum, South American opossum, and Australian tammar wallaby) and one monotreme (platypus) genomes. These ancient mammalian genomes are characterized by unusual architectural features with respect to G + C and repeat content, as well as compression relative to human. Approximately 14% and 34% of the human sequence forms alignments with the orthologous sequence from platypus and the marsupials, respectively; these numbers are distinctly lower than that observed with nonprimate eutherian mammals (45-70%). The alignable sequences between human and each marsupial species are not completely overlapping (only 80% common to all three species) nor are the platypus-alignable sequences completely contained within the marsupial-alignable sequences. Phylogenetic analysis of synonymous coding positions reveals that platypus has a notably long branch length, with the human-platypus substitution rate being on average 55% greater than that seen with human-marsupial pairs. Finally, analyses of the major mammalian lineages reveal distinct patterns with respect to the common presence of evolutionarily conserved vertebrate sequences. Our results confirm that genomic sequence from noneutherian mammals can contribute uniquely to unraveling the functional and evolutionary histories of the mammalian genome.  相似文献   

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Sublingual immunotherapy (SLIT) is accepted in the official documents and is currently used in many European countries. In recent years, new clinical data on efficacy and safety have been published, including meta-analyses in adults and children and surveys of safety in children younger than age 5 years. Moreover, it has been shown that, similar to the injection route, SLIT can prevent the onset of new sensitizations and the onset of asthma. Additionally, the mechanisms of action are beginning to be systematically studied. Some points need further investigation, such as the effect in asthma, the mechanisms of action, and the optimal dose to be administered.  相似文献   

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Since first studied more than 5 decades ago the risk of travelers'diarrhea for persons going from industrialized regions to developing countries has remained high. Most cases of illness are caused by bacterial agents. Travelers' diarrhea is associated with temporary disability and it may progress to chronic intestinal illness and postinfectious irritable bowel syndrome. Exercising care about food and beverage intake, the use of rifaximin prophylaxis for selective patients, and self-treatment of all resultant illness will continue to be the way in which the disease is prevented or managed best by travelers. Future approaches will be aimed at making host regions safer and providing more effective methods of treatment and prevention of enteric disease during short-term international travel.  相似文献   

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BACKGROUND This study determined the composition and diversity of intestinal microflora in patients with colorectal adenoma(CRA),which may provide precedence for investigating the role of intestinal microflora in the pathogenesis of colorectal tumors,the composition of intestinal microflora closely related to CRA,and further validating the possibility of intestinal flora as a biomarker of CRA.AIM To study the relationship between intestinal microflora and CRA.METHODS This is a prospective control case study from October 2014 to June 2015 involving healthy volunteers and patients with advanced CRA.High-throughput sequencing and bioinformatics analysis were used to investigate the composition and diversity of intestinal microflora in 36 healthy subjects and 49 patients with advanced CRA.Endpoints measured were operational taxonomic units of intestinal flora,as well as their abundance and diversity(αandβtypes).RESULTS In this study,the age,gender,body mass index,as well as location between controls and patients had no significant differences.The mucosa-associated gut microbiota diversity and bacterial distribution in healthy controls and colorectal adenomas were similar.The operational taxonomic unit,abundance,andαandβdiversity were all reduced in patients with CRA compared to controls.At the phylum level,the composition of intestinal microflora was comparable between patients and controls,but the abundance of Proteobacteria was increased,and Firmicutes and Bacteroides were significantly decreased(P<0.05).The increase in Halomonadaceae and Shewanella algae,and reduction in Coprococcus and Bacteroides ovatus,could serve as biomarkers of CRA.High-throughput sequencing confirms the special characteristics and diversity of intestinal microflora in healthy controls and patients with CRA.CONCLUSION The diversity of intestinal microflora was decreased in patients with CRA.An increase in Halomonadaceae and Shewanella algae are markers of CRA.  相似文献   

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