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61.
Dr. med. Florian Weis Daniela Hauer Prof. Dr.med. Gustav Schelling 《Psychosomatik und Konsiliarpsychiatrie》2008,2(1):39-43
Extracorporeal membrane oxygenation (ECMO) represents a valuable tool in the armamentarium of life and organ support measures in intensive care medicine. ECMO is used in fulminant pulmonary failure to prevent acute hypoxia and to allow CO2 removal (veno-venous ECMO) or, in highly selected cases of acute cardiovascular failure, to maintain organ perfusion and gas exchange and to prevent imminent death (veno-arterial ECMO). The purpose of ECMO is to allow time for intrinsic recovery of the lungs and heart. Alternatively, ECMO can be used as bridging device until a suitable organ for transplantation is available or the implantation of an artificial heart is feasible. ECMO carries a high complication rate and its use should be limited to highly specialized centers. In rare cases, mobile ECMO systems can be used by dedicated teams which allow transportation of critically ill patients over longer distances to specialized institutions. There is no unequivocal evidence from controlled studies that the use of ECMO in adults improves survival in larger cohorts, but its use in selected cases can be life saving. Long-term survivors of ECMO therapy report significant impairments in health-related quality of life (HRQL) when compared to healthy controls. There is, however, a gradual recovery and improvement in HRQL over a prolonged period after discharge from the intensive care unit and severe limitations in cognitive or physical function are rare. The incidence of chronic post-traumatic stress disorder (PTSD) in patients after ECMO can reach up to 30%. PTSD has a major negative impact on HRQL outcomes of ECMO therapy. PTSD or other stress-related disorders need to be diagnosed and adequately treated to allow adequate recovery from the extreme illness these patients have survived. 相似文献
62.
63.
Musto H Naya H Zavala A Romero H Alvarez-Valín F Bernardi G 《Biochemical and biophysical research communications》2006,347(1):1-3
Two years ago, we showed that positive correlations between optimal growth temperature (T(opt)) and genome GC are observed in 15 out of the 20 families of prokaryotes we analyzed, thus indicating that "T(opt) is one of the factors that influence genomic GC in prokaryotes". Our results were disputed, but these criticisms were demonstrated to be mistaken and based on misconceptions. In a recent report, Wang et al. [H.C. Wang, E. Susko, A.J. Roger, On the correlation between genomic G+C content and optimal growth temperature in prokaryotes: data quality and confounding factors, Biochem. Biophys. Res. Commun. 342 (2006) 681-684] criticize our results by stating that "all previous simple correlation analyses of GC versus temperature have ignored the fact that genomic GC content is influenced by multiple factors including both intrinsic mutational bias and extrinsic environmental factors". This statement, besides being erroneous, is surprising because it applies in fact not to ours but to the authors' article. Here, we rebut the points raised by Wang et al. and review some issues that have been a matter of debate, regarding the influence of environmental factors upon GC content in prokaryotes. Furthermore, we demonstrate that the relationship that exists between genome size and GC level is valid for aerobic, facultative, and microaerophilic species, but not for anaerobic prokaryotes. 相似文献
64.
Frederico Figueiredo Amancio Tiago Pires Heringer Cristina da Cunha Hueb Barata de Oliveira Liliane Boaventura Fassy Frederico Bruzzi de Carvalho Daniela Pagliari Oliveira Claudio Dornas de Oliveira Fernando Otoni Botoni Fernanda do Carmo Magalh?es José Roberto Lambertucci Mariangela Carneiro 《PloS one》2015,10(6)
The purpose of our study was to describe the clinical profile of dengue-infected patients admitted to Brazilian intensive care units (ICU) and evaluate factors associated with death. A longitudinal, multicenter case series study was conducted with laboratory-confirmed dengue patients admitted to nine Brazilian ICUs situated in Minas Gerais state, southeastern Brazil from January 1, 2008, to December 31, 2013. Demographic, clinical and laboratory data; disease severity scores; and mortality were evaluated. A total of 97 patients were studied. The in-ICU and in-hospital mortality rates were 18.6% and 19.6%, respectively. Patients classified as having severe dengue according to current World Health Organization classifications showed an increased risk of death in a univariate analysis. Nonsurvivors were older, exhibited lower serum albumin concentrations and higher total leukocyte counts and serum creatinine levels. Other risk factors (vomiting, lethargy/restlessness, dyspnea/respiratory distress) were also associated with death in a univariate analysis. Multivariate analysis indicated that in-hospital mortality was significantly associated with Acute Physiology and Chronic Health Evaluation II and the Sequential Organ Failure Assessment score. The ICU and in-hospital mortality observed in this study were higher than values reported in similar studies. An increased frequency of ICU admission due to severe organ dysfunction, higher severity indices and scarcity of ICU beds may partially explain the higher mortality. 相似文献
65.
Chaves DF Ferrer PP de Souza EM Gruz LM Monteiro RA de Oliveira Pedrosa F 《Proteomics》2007,7(20):3759-3763
Herbaspirillum seropedicae is an endophytic diazotroph associated with economically important crops such as rice, sugarcane, and wheat. Here, we present a 2-D reference map for H. seropedicae. Using MALDI-TOF-MS we identified 205 spots representing 173 different proteins with a calculated average of 1.18 proteins/gene. Seventeen hypothetical or conserved hypothetical ORFs were shown to code for true gene products. These data will support the genome annotation process and provide a basis on which to undertake comparative proteomic studies. 相似文献
66.
Maria Siller Rajendra P Janapatla Zaid A Pirzada Christine Hassler Daniela Zinkl Emmanuelle Charpentier 《BMC microbiology》2008,8(1):1-17
Background
The luxS/AI-2 signaling pathway has been reported to interfere with important physiological and pathogenic functions in a variety of bacteria. In the present study, we investigated the functional role of the streptococcal luxS/AI-2 system in metabolism and diverse aspects of pathogenicity including the adaptation of the organism to stress conditions using two serotypes of Streptococcus pyogenes, M1 and M19.Results
Exposing wild-type and isogenic luxS-deficient strains to sulfur-limited media suggested a limited role for luxS in streptococcal activated methyl cycle metabolism. Interestingly, loss of luxS led to an increased acid tolerance in both serotypes. Accordingly, luxS expression and AI-2 production were reduced at lower pH, thus linking the luxS/AI-2 system to stress adaptation in S. pyogenes. luxS expression and AI-2 production also decreased when cells were grown in RPMI medium supplemented with 10% serum, considered to be a host environment-mimicking medium. Furthermore, interaction analysis with epithelial cells and macrophages showed a clear advantage of the luxS-deficient mutants to be internalized and survive intracellularly in the host cells compared to the wild-type parents. In addition, our data revealed that luxS influences the expression of two virulence-associated factors, the fasX regulatory RNA and the virulence gene sibA (psp).Conclusion
Here, we suggest that the group A streptococcal luxS/AI-2 system is not only involved in the regulation of virulence factor expression but in addition low level of luxS expression seems to provide an advantage for bacterial survival in conditions that can be encountered during infections. 相似文献67.
Francisco Romero Francisco Javier Caballero Francisco Castillo José Manuel Roldán 《Archives of microbiology》1985,143(2):111-116
Anti-glutamine synthetase serum was raised in rabbits by injecting purified glutamine synthetase (GS) of the phototrophic bacterium Rhodopseudomonas capsulata E1F1. The antibodies were purified to monospecificity by immunoaffinity chromatography in GS-sepharose gel. These anti-GS antibodies were used to measure the antigen levels in crude extracts from bacteria, grown phototrophically with dinitrogen, nitrate, nitrite, ammonia, glutamate, glutamine or alanine as nitrogen sources. The amount of GS detected by rocket immunoelectrophoresis was proportional to Mn2+-dependent transferase activity measured in the crude extracts. Addition of GS inhibitor l-methionine-d,l-sulfoximine (MSX) to the actively growing cells promoted increased antigen levels, that were not found in the presence of glutamine or chloramphenicol. The ammonia-induced decrease in GS relative levels was reverted by MSX. GS levels remained constant when phototrophically growing cells were kept in the dark.Abbreviations GS
glutamine synthetase
- MOPS
2-(N-morpholine) propane sulfonate
- MSX
l-methionine-d,l-sulfoximine 相似文献
68.
69.
Histone hyperacetylation in mitosis prevents sister chromatid separation and produces chromosome segregation defects 下载免费PDF全文
Posttranslational modifications of core histones contribute to driving changes in chromatin conformation and compaction. Herein, we investigated the role of histone deacetylation on the mitotic process by inhibiting histone deacetylases shortly before mitosis in human primary fibroblasts. Cells entering mitosis with hyperacetylated histones displayed altered chromatin conformation associated with decreased reactivity to the anti-Ser 10 phospho H3 antibody, increased recruitment of protein phosphatase 1-delta on mitotic chromosomes, and depletion of heterochromatin protein 1 from the centromeric heterochromatin. Inhibition of histone deacetylation before mitosis produced defective chromosome condensation and impaired mitotic progression in living cells, suggesting that improper chromosome condensation may induce mitotic checkpoint activation. In situ hybridization analysis on anaphase cells demonstrated the presence of chromatin bridges, which were caused by persisting cohesion along sister chromatid arms after centromere separation. Thus, the presence of hyperacetylated chromatin during mitosis impairs proper chromosome condensation during the pre-anaphase stages, resulting in poor sister chromatid resolution. Lagging chromosomes consisting of single or paired sisters were also induced by the presence of hyperacetylated histones, indicating that the less constrained centromeric organization associated with heterochromatin protein 1 depletion may promote the attachment of kinetochores to microtubules coming from both poles. 相似文献
70.
Montero M Lobatón CD Gutierrez-Fernández S Moreno A Alvarez J 《The Journal of biological chemistry》2003,278(50):49972-49979
In HeLa cells, histamine induces production of inositol 1,4,5-trisphosphate (InsP3) and release of Ca2+ from the endoplasmic reticulum (ER). Ca2+ release is typically biphasic, with a fast and brief initial phase, followed by a much slower and prolonged one. In the presence of inhibitors of protein kinase C (PKC), including staurosporine and the specific inhibitors GF109203X and Ro-31-8220, the fast phase continued until the ER became fully empty. On the contrary, treatment with phorbol 12,13-dibutyrate inhibited Ca2+ release. Staurosporine had no effect on InsP3-induced Ca2+ release in permeabilized cells and did not modify either histamine-induced InsP3 production. These data suggest that histamine induces Ca2+ release and with a short lag activates PKC to down-regulate it. Consistently, Ca2+ oscillations induced by histamine were increased in amplitude and decreased in frequency in the presence of PKC inhibitors. We show also that mitochondrial [Ca2+] was much more sensitive to changes in ER-Ca2+ release induced by PKC modulation than cytosolic [Ca2+]. PKC inhibitors increased the histamine-induced mitochondrial [Ca2+] peak by 4-fold but increased the cytosolic [Ca2+] peak only by 20%. On the contrary, PKC activation inhibited the mitochondrial [Ca2+] peak by 90% and the cytosolic one by only 50%. Similarly, the combination of PKC inhibitors with the mitochondrial Ca2+ uniporter activator SB202190 led to dramatic increases in mitochondrial [Ca2+] peaks, with little effect on cytosolic ones. This suggests that activation of ER-Ca2+ release by PKC inhibitors could be involved in apoptosis induced by staurosporine. In addition, these mechanisms allow flexible and independent regulation of cytosolic and mitochondrial [Ca2+] during cell stimulation. 相似文献