Cell proliferation at 122 degrees C and isotopically heavy CH4 production by a hyperthermophilic methanogen under high-pressure cultivation

We have developed a technique for cultivation of chemolithoautotrophs under high hydrostatic pressures that is successfully applicable to various types of deep-sea chemolithoautotrophs, including methanogens. It is based on a glass-syringe-sealing liquid medium and gas mixture used in conjunction with a butyl rubber piston and a metallic needle stuck into butyl rubber. By using this technique, growth, survival, and methane production of a newly isolated, hyperthermophilic methanogen Methanopyrus kandleri strain 116 are characterized under high temperatures and hydrostatic pressures. Elevated hydrostatic pressures extend the temperature maximum for possible cell proliferation from 116°C at 0.4 MPa to 122°C at 20 MPa, providing the potential for growth even at 122°C under an in situ high pressure. In addition, piezophilic growth significantly affected stable carbon isotope fractionation of methanogenesis from CO₂. Under conventional growth conditions, the isotope fractionation of methanogenesis by M. kandleri strain 116 was similar to values (−34‰ to−27‰) previously reported for other hydrogenotrophic methanogens. However, under high hydrostatic pressures, the isotope fractionation effect became much smaller (<−12‰), and the kinetic isotope effect at 122°C and 40 MPa was −9.4‰, which is one of the smallest effects ever reported. This observation will shed light on the sources and production mechanisms of deep-sea methane.     

肺炎1号方的组方思路及理论创新

认为广东地区新型冠状病毒肺炎(简称"新冠肺炎")是以热毒为基本属性的疫疠之气所致,从发病季节及病邪性质看,可归属于温邪为主的疫疠范畴,可称之为"风温""温热疫".基于对广东地区新冠肺炎病因、病机的认识,分析肺炎1号方的组方思路与在清热解毒、透邪清宣及止咳化痰的同时使用益气养阴的理论创新点,为积极开展中医药救治新冠肺炎及...     

影响玉米秸秆微生物降解制肥的因素浅析

试验以粉碎后的玉米秸杆为原料进行好氧微生物降解制造有机肥，通过比较不同含水率和通气条件对秸秆降解效率的影响，以及降解过程中温度，pH，微生物量的变化，总结出微生物降解玉米秸秆过程的变化规律。由试验可知，水分与通气条件均是影响发酵效果的重要因素，且制造堆肥的最佳含水率在60％－70％。     

高血压患者脉压差与左心功能的关系

INTRODUCTIONRecentlymanyreportsrevealedpulsepressureiscloselycorrelatedwithoccurrenceanddeathofcoronarydisease犤１－４犦．Butitisnotclearwiththerelationshipbetweenpulsepressureandventricularfunctionofhypertensionpatients．Toinvestigateeffectofpulsepressureonventricularfunctionofhypertensionpatients，weexploredrelation－shipofpulsepressureandventricularfunction．MATERIALSANDMETHODSMaterials４２hypertensionpatientswerereceivedfrom１９９５to２０００toourhospitalanddiagnosedashypertens…     

High resolution spiral CT scan in the diagnosis of pseudoaneurysm of ascending aorta

Pseudoaneurysms of the ascending aorta are rare (<1%), and extremely rare from aortic vent site, but can be a lifethreatening complication. The basic methods of diagnosis are computed tomography scan and aortography. We report high resolution spiral CT may provide the best less invasive means in the diagnosis of the pseudoaneurysm of the ascending aorta originated from the aortic vent site.     

构叶的降压作用及其机制初步分析

实验表明构叶浸膏剂(2.5g,5g/kg)灌胃,能剂量依赖性地降低自发性高血压大鼠血压。并观察到在大鼠肛尾肌,构叶总甙(0.1％,0.3％)能使去氧肾上腺素累积量效曲线右移,同时最大效应下降。用L—B公式证明去氧肾上腺素的解离常数未变,说明构叶总甙具有非竞争性α受体阻断作用。该作用可能与构叶的降压效应有关。     

Deep-sea hydrothermal vent bacteria related to human pathogenic Vibrio species

Vibrio species are both ubiquitous and abundant in marine coastal waters, estuaries, ocean sediment, and aquaculture settings worldwide. We report here the isolation, characterization, and genome sequence of a novel Vibrio species, Vibrio antiquarius, isolated from a mesophilic bacterial community associated with hydrothermal vents located along the East Pacific Rise, near the southwest coast of Mexico. Genomic and phenotypic analysis revealed V. antiquarius is closely related to pathogenic Vibrio species, namely Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi, and Vibrio vulnificus, but sufficiently divergent to warrant a separate species status. The V. antiquarius genome encodes genes and operons with ecological functions relevant to the environment conditions of the deep sea and also harbors factors known to be involved in human disease caused by freshwater, coastal, and brackish water vibrios. The presence of virulence factors in this deep-sea Vibrio species suggests a far more fundamental role of these factors for their bacterial host. Comparative genomics revealed a variety of genomic events that may have provided an important driving force in V. antiquarius evolution, facilitating response to environmental conditions of the deep sea.With more than 110 recognized species, the genus Vibrio comprises a diverse group of heterotrophic bacteria, of which many are known pathogens, causing disease in animals and humans (1, 2). Vibrio cholerae is the most notorious because it is the causative agent of cholera. Vibrio vulnificus and Vibrio parahaemolyticus cause severe illness in humans and are associated with consumption of contaminated seafood (3, 4). Vibrio harveyi (5), Vibrio anguillarum (6, 7), and V. parahaemolyticus (8) continue to cause substantial economic losses to the aquaculture industry worldwide.Vibrios demonstrate a wide range of niche specialization: for example, free-living, attached to biotic and abiotic surfaces, and resident in both estuarine and marine habitats (9). The deep sea constitutes the largest habitat of the biosphere that supports microbial communities across three domains of life and represents an environment where physiochemical parameters—such as low temperature, high salinity, and high pressure—modulate community structure (10, 11). Several studies have shown the presence of physiologically, metabolically, and phylogenetically diverse mesophilic microbial communities in the deep sea, including Vibrio species (12–15). Barotolerant Vibrio spp. have been isolated from deep-sea sediment and from the gut microflora of invertebrates and fish collected from a variety of deep-sea habitats, including hydrothermal vents (16, 17). For example, strains of Vibrio, Aeromonas, and Pseudomonas spp. were isolated from mud-water samples collected at a depth of 4,940 m, 150 miles east of Cape Canaveral, Florida (18). Several culture-dependent and -independent studies have confirmed the ubiquity of vibrios, and suggested Vibrio populations generally comprise approximately 1% (by molecular techniques) of the total bacterioplankton in estuaries (19), in contrast to culture-based studies demonstrating that vibrios can comprise up to 10% of culturable marine bacteria (20). Clearly, vibrios are ubiquitous and abundant in the aquatic environment on a global scale, including both seawater and sediment (19, 21–25), and repeatedly shown to be present in high densities in and on marine organisms, such as corals (26), fish (27–29), mollusks (30), seagrass, sponges, shrimp (28, 31), and zooplankton (16, 17, 28, 32, 33).During dives of the deep-sea submersibles Alvin and Nautile in 1999 along the East Pacific Rise, southwest of the Mexico coast, samples of water surrounding sulfide chimneys of a hydrothermal vent community were collected and four mesophilic bacterial isolates were cultured, which were subsequently tested for phenotypic traits, including growth on V. cholerae selective thiosulfate-citrate-bile-salts-sucrose (TCBS) agar (Oxoid). The sampling locations from where these four mesophilic bacteria were isolated are described in

急性肺损伤/急性呼吸窘迫综合征患者呼出气冷凝液中8-异前列腺素检测的临床意义

目的观察急性肺损伤/急性呼吸窘迫综合征（ALI/ARDS）患者呼出气冷凝液（EBC）中8-异前列腺素（8-iso-PG）的水平,探讨其临床价值。方法 2009年4月至2009年9月严重外伤和手术后入住南通大学第二附属医院重症监护病房（ICU）行机械通气的31例ALI/ARDS患者为研究组,根据入院第1 d和第5 d的病情变化,分为持续ALI组（10例）,持续ARDS组（9例）,病情加重组（ALI加重为ARDS,6例）,以及病情缓解组（ARDS缓解为ALI,6例）。对ALI/ARDS患者使用改进的EcoScreen冷凝器采集EBC标本。30名健康体检者为对照组,自主呼吸收集EBC标本。采用EIA法测定EBC中8-iso-PG浓度,观察不同肺损伤分级及预后患者EBC中8-iso-PG水平的差异,并与临床指标作相关性分析。结果 ALI/ARDS患者第1 d和第5 d时EBC中8-iso-PG水平均高于对照组[（45.53±14.37）ng/L和（45.31±12.42）ng/L比（19.47±4.06）ng/L,P〈0.001]。持续ALI组EBC中8-iso-PG水平在第1 d和第5 d时为（39.23±11.49）ng/L和（37.42±12.11）ng/L（P〉0.05）,显著低于持续ARDS组[（52.57±9.87）ng/L和（51.93±10.45）ng/L,P〉0.05）]。病情加重组EBC中8-iso-PG水平在第1 d和第5 d时分别为（32.56±9.70）ng/L和（51.43±10.93）ng/L（P〈0.05）,病情缓解组第1 d和第5 d时分别为（58.43±13.47）ng/L和（42.42±10.42）ng/L（P〈0.05）。病死组第1 d和第5 d时EBC中8-iso-PG水平为（53.94±12.25）ng/L和（57.33±10.48）ng/L,显著高于存活组[（39.16±13.65）ng/L和（36.19±7.96）ng/L,P〈0.01]。EBC中8-iso-PG水平与外周血WBC、LIS评分、X线评分、AaDO2/PaO2、AaDO2、VT、VE及MEWS评分呈正相关（P〈0.05）,与PaO2/PAO2、PaO2/FiO2呈负相关（P〈0.05）。结论 ALI患者EBC中8-iso-PG水平对判断病情严重程度和评估预后有一定的参考价值。