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3.
Anesth Analg ; 114(3): 622-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22190557

RESUMO

BACKGROUND: Waterless antiseptic surgical hand scrub (1% chlorhexidine gluconate and 61% ethyl alcohol, Avagard™; 3M Health Care, St. Paul, MN), alcohol-only cleanser (62% ethyl alcohol), and traditional surgical scrub (5-minute scrub with 4% chlorhexidine soap using a sterile scrub brush with water) are techniques used for hand cleansing and disinfection. We hypothesized that alcohol-only cleanser and waterless antiseptic scrub (Avagard) would be as effective as a traditional surgical scrub for hand cleansing before placement of central venous catheters. METHODS: Fingers of subjects were plate-cultured for 24 hours after 5 methods of hand cleansing: method 1: traditional surgical scrub (n = 49 plates produced by 14 subjects); method 2: traditional surgical scrub (5-minute scrub with water, brush, and 4% chlorhexidine soap) followed by a 15-minute break, then alcohol-only cleanser (62% alcohol) (n = 49 plates produced by 14 subjects); method 3: alcohol-only cleanser alone (n = 49 plates produced by 14 subjects); method 4: alcohol-only cleanser (62% alcohol), followed by a 15-minute break, then traditional surgical scrub (5-minute scrub with brush, and 4% chlorhexidine soap with water) (n = 49 plates produced by 14 subjects); and method 5: waterless surgical scrub (Avagard) alone (n = 116 plates produced by 38 subjects). The 15-minute break was introduced to allow a short period of recontamination, and to test for residual effects from prior cleansing. RESULTS: Alcohol-only cleanser alone (method 3) was significantly less effective than the traditional surgical scrub (method 1) (P < 0.001; 82% plate growth). Waterless surgical scrub (Avagard) (method 5) had a 0% observed difference (95% confidence interval [CI]: -14% to 11%) compared with the traditional 5-minute scrub (method 1) (P = 0.99; 16% plate growth). When a traditional surgical scrub was used first followed by a 15-minute period of recontamination, there was a 6% observed difference in method 2 from reference (method 1) (95% CI: -10% to 22%), and 0% observed difference in method 4 from reference (95% CI: -15% to 15%). CONCLUSION: As the initial cleansing method, the alcohol-only cleanser (method 3) was significantly less effective than the traditional surgical scrub (method 1) (P < 0.001).


Assuntos
Cateterismo Venoso Central/normas , Desinfecção/normas , Etanol/administração & dosagem , Desinfecção das Mãos/normas , Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Clorexidina/análogos & derivados , Contagem de Colônia Microbiana/métodos , Desinfecção/métodos , Feminino , Desinfecção das Mãos/métodos , Humanos , Masculino , Sabões/administração & dosagem
4.
J Endocrinol Invest ; 33(10): 745-50, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20479568

RESUMO

Activation of the progesterone receptor (PR) inhibits cell proliferation in various reproductive tissues. However, the molecular mechanisms underlying the regulation of cell proliferation by PR remain poorly understood. It is well established that Krüppel-like factor 4 (KLF4), a family of zinc fingercontaining transcription factors, induces cell cycle arrest in epithelial cells. In this study, we investigated whether KLF4 served as a target of PR activation during cell proliferation using human endometrial epithelial cells. PR agonists, progesterone and dienogest, were found to produce a lasting increase in the expression of KLF4 mRNA, followed by a decrease in cyclin D1 mRNA, and inhibit cell proliferation with G0/G1 arrest. KLF4 knockdown using KLF4 small interferingRNA abrogated the inhibition of cell proliferation by PR agonists. In addition, forced expression of KLF4 inhibited cyclin D1 promoter transactivation. These results suggest that PR agonists induce KLF4 expression and then inhibit cyclin D1 expression, and consequently inhibit cell proliferation in human endometrial epithelial cells. In terms of human reproductive tissue, KLF4 may be a factor concerning cell cycle, directly responsive to PR activation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endométrio/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/fisiologia , Progesterona/farmacologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Fase G1/genética , Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Genes bcl-1/efeitos dos fármacos , Genes bcl-1/fisiologia , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores de Progesterona/agonistas , Receptores de Progesterona/metabolismo , Receptores de Progesterona/fisiologia , Fase de Repouso do Ciclo Celular/genética
5.
J Educ Perioper Med ; 22(4): E648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33447647

RESUMO

BACKGROUND: No studies have examined how journal clubs (JCs) are implemented in anesthesiology residency training programs. The goal of the study was to close this gap by (1) examining the format, content, and goals of JCs; (2) identifying features associated with higher resident attendance and JC success; and (3) examining program directors' perspectives on JCs. METHODS: A 41-question survey was sent to anesthesiology program directors. Answers were analyzed using multivariable logistic regression, multivariable linear regression, and exploratory factor analysis. RESULTS: Out of 117 surveys sent across the United States, 80 program directors responded (68.4% response rate). Of the 80 programs, 77 (96.3%) programs have a JC, with 93.2% of them existing for more than 2 years. Most JCs (62.5%) neither formally appraised articles before meetings, nor formally evaluated their JC (59.7%). Faculty alone organized 44.4% and moderated 69.9% of the JCs. The role of residents was primarily limited to presenting selected articles with faculty guidance (83.3%). The average resident attendance was 49.7%. A multivariable linear regression analysis identified mandatory resident attendance, faculty turnout of >5 members, and longer intervals between JC meetings as features associated with higher resident attendance. Only 49.3% of JCs were successful as defined a priori by resident attendance >50% and longevity of ≥2 years. Features associated with JC success based on multivariable logistic regression included mandatory resident attendance and complimentary food. CONCLUSIONS: This largest survey of JCs in anesthesiology found that while JCs are widely established, half of them could be improved.

6.
J Inherit Metab Dis ; 32 Suppl 1: S37-40, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19408133

RESUMO

We report a Japanese girl affected with a neonatal-onset form of propionic acidaemia (PA). She developed severe metabolic crisis after dehydration at 2 years of age. Bradycardia with complete atrioventricular block responded to haemodiafiltration, but severe cardiac failure was refractory to inotropic treatment. She was diagnosed with acute cardiac dysfunction caused by PA-induced metabolic crisis. Extracorporeal membrane oxygenation (ECMO), a technique for providing mechanical circulatory support, was required. This is the first case report of a PA patient who recovered from a life-threatening metabolic crisis with cardiac failure by ECMO. Cardiac failure may be a cause of death, but it is occasionally an under-recognized complication. Mitochondrial dysfunction in the myocardium due to propionyl-CoA could contribute to the pathomechanism of cardiac complications of PA. We believe that ECMO should be attempted in PA patients with cardiac failure, in addition to haemodiafiltration and other therapeutic measures, because doing so may lead to the recovery of cardiac dysfunction, as was evident in our patient. In conclusion, prompt investigations and management of cardiac complications should be performed immediately during PA-induced metabolic crises.


Assuntos
Oxigenação por Membrana Extracorpórea , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Acidemia Propiônica/complicações , Pré-Escolar , Estado Terminal , Feminino , Hemodiafiltração , Humanos , Acidemia Propiônica/terapia , Fatores de Tempo
8.
Trends Biochem Sci ; 26(8): 465-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504612

RESUMO

Three enzymes, peptidyl-arginine deiminase from Porphyromonas gingivalis, arginine deiminase and amidinotransferase are traditionally classified separately. By combining PSI-BLAST and FUGUE, data presented in this article describe how these enzymes belong to a novel superfamily, adopting a common fold and sharing similar catalytic mechanisms.


Assuntos
Amidinotransferases/metabolismo , Guanidinas/metabolismo , Hidrolases/metabolismo , Amidinotransferases/química , Sequência de Aminoácidos , Catálise , Hidrolases/química , Dados de Sequência Molecular , Porphyromonas gingivalis/enzimologia , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas , Homologia de Sequência de Aminoácidos
9.
Trends Biochem Sci ; 23(7): 239-42, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9697410

RESUMO

Sequence analyses show that Spätzle, the Drosophila melanogaster Toll-receptor ligand, shows striking similarity to nerve growth factor and coagulogen. Comparative modelling suggests that Spätzle adopts a cystine-knot fold and forms a dimer that contains a single, intermolecular disulphide bridge. Proteolytically cleaved Spätzle could therefore dimerize and activate the Toll receptor by inducing receptor dimerization.


Assuntos
Proteínas de Drosophila , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Sequência de Aminoácidos , Animais , Proteínas Sanguíneas/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Insetos/genética , Modelos Moleculares , Dados de Sequência Molecular , Fatores de Crescimento Neural/genética , Conformação Proteica , Homologia de Sequência de Aminoácidos
11.
J Endocrinol Invest ; 31(7): 636-41, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18787383

RESUMO

Dienogest is a selective progestin that has been shown to arrest ovarian follicular development in women, without affecting gonadotropin secretion. As luteal progesterone or exogeneous progestins are known to suppress ovarian folliculogenesis via the inhibition of gonadotropin secretion, this action of dienogest on ovaries seems to be unique. To examine the underlying mechanism of the antifolliculogenic effect of dienogest, female cynomolgus monkeys were treated with a single oral dose of 0.1 mg/kg dienogest on day 7 of the menstrual cycle. Plasma FSH, estradiol (E2), and progesterone levels were measured up to 15 days after dosing. In an additional experiment, ovaries were excised 24 h after dosing for histological examinations. As a result, plasma E2 level declined within 24 h after dosing, while dienogest did not decreased FSH level prior to E2 decline. After decline of E2 level, the low level of E2 was sustained for more than 11 days. It is considered that a single oral dose of dienogest induced atresia of the dominant follicle. In the histological examination, two out of three animals showed decline in E2 level. The ovarian dominant follicles from these animals showed apoptotic changes in granulosa cells with scattered aromatase expression within 24 h after dosing. These results indicate that the induction of atresia of the ovarian dominant follicle by direct action would be a possible mechanism of dienogest to inhibit plasma E2 level.


Assuntos
Apoptose/efeitos dos fármacos , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Células da Granulosa , Antagonistas de Hormônios/farmacologia , Nandrolona/análogos & derivados , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Animais , Feminino , Atresia Folicular/metabolismo , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/fisiologia , Humanos , Macaca fascicularis , Ciclo Menstrual/fisiologia , Nandrolona/farmacologia , Folículo Ovariano/citologia , Progesterona/sangue , Progestinas/farmacologia
12.
J Thorac Cardiovasc Surg ; 155(6): 2455-2463.e5, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29548590

RESUMO

OBJECTIVE: The study objective was to identify patients who are likely to develop progressive kidney dysfunction (acute kidney disease) before their hospital discharge after cardiac surgery, allowing targeted monitoring of kidney function in this at-risk group with periodic serum creatinine measurements. METHODS: Risks of progression to acute kidney disease (a state in between acute kidney injury and chronic kidney disease) were modeled from acute kidney injury stages (Kidney Disease: Improving Global Outcomes) in patients undergoing cardiac surgery. A modified Poisson regression with robust error variance was used to evaluate the association between acute kidney injury stages and the development of acute kidney disease (defined as doubling of creatinine 2-4 weeks after surgery) in this observational study. RESULTS: Acute kidney disease occurred in 4.4% of patients with no preexisting kidney disease and 4.8% of patients with preexisting chronic kidney disease. Acute kidney injury predicted development of acute kidney disease in a graded manner in which higher stages of acute kidney injury predicted higher relative risk of progressive kidney disease (area under the receiver operator characteristic curve = 0.82). This correlation persisted regardless of baseline kidney function (P < .001). Of note, development of acute kidney disease was associated with higher mortality and need for renal replacement therapy. CONCLUSIONS: The degree of acute kidney injury can identify patients who will have a higher risk of progression to acute kidney disease. These patients may benefit from close follow-up of renal function because they are at risk of progressing to chronic kidney disease or end-stage renal disease.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Insuficiência Renal Crônica , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/patologia , Estudos Retrospectivos
13.
BMC Bioinformatics ; 8 Suppl 1: S15, 2007 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-17430559

RESUMO

BACKGROUND: Thermophilic organisms are able to live at high temperatures ranging from 50 to > 100 degrees C. Their proteins must be sufficiently stable to function under these extreme conditions; however, the basis for thermostability remains elusive. Subtle differences between thermophilic and mesophilic molecules can be found when sequences or structures from homologous proteins are compared, but often these differences are family-specific and few general rules have been derived. The availability of complete genome sequences has now made it feasible to perform a large-scale comparison between mesophilic and thermophilic proteins, the latter of which primarily come from archaeal genomes although a few complete genomes of thermophilic eubacteria are also available. RESULTS: We compared mesophilic proteins with their thermophilic counterparts of archaeal or eubacterial origins independently. This was based on the assumption that in these two kingdoms, different mechanisms may have been exploited for the adaptation of proteins at high temperatures. We derived the environment specific amino acid compositions of thermophilic proteins from 10 archaeal and seven eubacterial genomes, by aligning a large number of sequences from thermophilic proteins with their close mesophilic homologues of known three-dimensional (3D) structure. We further analysed environment specific substitutions, which lead from mesophilic proteins to either archaeal or eubacterial thermophilic proteins. CONCLUSION: Our comparisons were based on homology-based structural predictions for a large number of thermophilic proteins. We demonstrated that thermal adaptation in the archaeal and eubacterial kingdoms is achieved in different ways. The main differences concern the usage of Gln, Ile and positively charged amino acids. In particular archaeal organisms appeared to have acquired thermostability by substituting non-charged polar amino acids (such as Gln) with Glu and Lys, and non-polar amino acids with Ile on the surface of proteins.


Assuntos
Archaea/química , Archaea/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Mapeamento Cromossômico/métodos , Meio Ambiente , Análise de Sequência de Proteína , Adaptação Fisiológica/genética , Substituição de Aminoácidos , Sequência Conservada , Alinhamento de Sequência , Temperatura
14.
Curr Opin Struct Biol ; 5(3): 377-82, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7583636

RESUMO

What is the significance of three-dimensional structural similarity? This fundamental question still remains unanswered in spite of advances in automatic structure comparison methods that have been made in the last few years. The answer to this question will give us a much deeper insight into the principles of protein architecture.


Assuntos
Conformação Proteica , Proteínas/química , Animais , Humanos , Alinhamento de Sequência
18.
Structure ; 7(2): 227-36, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10368289

RESUMO

BACKGROUND: Six-stranded beta barrels with a pseudo-twofold axis are found in several proteins. One group comprises a Greek-key structure with all strands antiparallel; an example is the N-terminal domain of ferredoxin reductase. Others involve parallel strands forming two psi structures (the double-psi beta barrel). A recently discovered example of the latter class is aspartate-alpha-decarboxylase (ADC) from Escherichia coli, a pyruvoyl-dependent tetrameric enzyme involved in the synthesis of pantothenate. RESULTS: Visual inspection and automated database searches identified the six-stranded double-psi beta barrel in ADC, Rhodobacter sphaeroides dimethylsulfoxide (DMSO) reductase, E. coli formate dehydrogenase H (FDHH), the plant defense protein barwin, Humicola insolens endoglucanase V (EGV) and, with a circular permutation, in the aspartic proteinases. Structure-based sequence alignments revealed several interactions including hydrophobic contacts or sidechain-mainchain hydrogen bonds that position the middle beta strand under a psi loop, which may significantly contribute to stabilizing the fold. The identification of key interactions allowed the filtering of weak sequence similarities to some of these proteins, which had been detected by sequence database searches. This led to the prediction of the double-psi beta-barrel domain in several families of proteins in eukaryotes and archaea. CONCLUSIONS: The structure comparison and clustering study of double-psi beta barrels suggests that there could be a common homodimeric ancestor to ADC, FDHH and DMSO reductase, and also to barwin and EGV. There are other protein families with unknown structure that are likely to adopt the same fold. In the known structures, the protein active sites cluster around the psi loop, indicating that its rigidity, protrusion and free mainchain functional groups may be well suited to providing a framework for catalysis.


Assuntos
Proteínas Ferro-Enxofre , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Celulase/química , Formiato Desidrogenases/química , Glutamato Descarboxilase/química , Hidrogenase/química , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multienzimáticos/química , Oxirredutases/química , Proteínas de Plantas/química , Alinhamento de Sequência
19.
J Mol Biol ; 310(1): 243-57, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11419950

RESUMO

FUGUE, a program for recognizing distant homologues by sequence-structure comparison (http://www-cryst.bioc.cam.ac.uk/fugue/), has three key features. (1) Improved environment-specific substitution tables. Substitutions of an amino acid in a protein structure are constrained by its local structural environment, which can be defined in terms of secondary structure, solvent accessibility, and hydrogen bonding status. The environment-specific substitution tables have been derived from structural alignments in the HOMSTRAD database (http://www-cryst.bioc. cam.ac.uk/homstrad/). (2) Automatic selection of alignment algorithm with detailed structure-dependent gap penalties. FUGUE uses the global-local algorithm to align a sequence-structure pair when they greatly differ in length and uses the global algorithm in other cases. The gap penalty at each position of the structure is determined according to its solvent accessibility, its position relative to the secondary structure elements (SSEs) and the conservation of the SSEs. (3) Combined information from both multiple sequences and multiple structures. FUGUE is designed to align multiple sequences against multiple structures to enrich the conservation/variation information. We demonstrate that the combination of these three key features implemented in FUGUE improves both homology recognition performance and alignment accuracy.


Assuntos
Biologia Computacional/métodos , Dobramento de Proteína , Proteínas/química , Software , Algoritmos , Substituição de Aminoácidos , Sequência Conservada , Bases de Dados como Assunto , Ligação de Hidrogênio , Internet , Estrutura Secundária de Proteína , Sensibilidade e Especificidade , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Solventes
20.
Kyobu Geka ; 58(2): 128-32, 2005 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-15724475

RESUMO

Autologous fibrin sealant (AFS) which is not based on the conventional method of co-administering fibrinogen, thrombin and aprotinin was prepared by Vivostat system, and was used in coronary artery bypass grafting (CABG). The purpose of this study was to investigate the safety and efficacy of the AFS prepared by the Vivostat system. In 6 of 68 cases of CABG, normal AFS was not prepared due to device failures. AFS was prepared and sprayed in 62 cases. There were the total of 230 anastomosis sprayed AFS and the bleeding could not seen in 225 anastomosis. Surgical hemostatic procedures (4 cases) were or other sealant usage (1 case) was performed 5 bleeding anastomosis sites. The rate of hemostasis at the anastomosis using AFS was 97.8%. This study was conducted in patients undergoing CABG. In this group of patients, a number of commercial available fibrin sealant products are routinely used. The usefulness of Vivostat as medical device to prepare and administer AFS was confirmed in this study.


Assuntos
Ponte de Artéria Coronária , Adesivo Tecidual de Fibrina/normas , Adesivo Tecidual de Fibrina/uso terapêutico , Hemostasia Cirúrgica , Adulto , Idoso , Coleta de Amostras Sanguíneas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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