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1.
Antimicrob Agents Chemother ; 57(4): 1998-2000, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23403427

RESUMO

Central venous catheters commonly develop central line-associated bloodstream infections. In vitro antibiotic lock therapy (ALT) was simulated on 10 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates imbedded in biofilm-coated silicon disks. Five days of 4-h daily exposures to daptomycin (2.5 mg/ml) in 25% ethanol or minocycline (3 mg/ml) plus 25% ethanol and 30 mg/ml EDTA resulted in significantly greater elimination of MRSA colonization than treatment with minocycline alone.


Assuntos
Biofilmes/efeitos dos fármacos , Daptomicina/farmacologia , Ácido Edético/farmacologia , Etanol/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Minociclina/farmacologia , Combinação de Medicamentos
2.
AIDS Res Hum Retroviruses ; 27(6): 659-67, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21054216

RESUMO

The purpose of this study was to determine if switching to an Lopinavir/ritonavir (LPV/r)-containing regimen resulted in greater immune reconstitution in patients with immunologic failure despite complete viral suppression with highly active antiretroviral therapy (HAART). Twenty patients with partial or no immune response to HAART despite viral suppression were enrolled. Ten were randomized to stay on their current regimen and 10 were randomized to LPV/r plus their current NRTI backbone. T cell subsets, ex vivo apoptosis, and the percent of circulating cells with detectable intracellular HIV-1 RNA were measured. The mean increase in CD4(+) count at 6 months was 116/mm(3) (172-288) for the LPV/r-containing arm versus 32/mm(3) (264-296) for continuation regimens (p = 0.03). The number of patients with an increase ≥50 cells/mm(3) was also greater in the LPV/r arm (7/9 versus 2/10, p = 0.01). This paralleled a decrease in ex vivo apoptosis of naive CD4(+) T cells at 6 months (21.7-11.0% for the LPV/r arm versus 17.3-18.9% for the continuation arm, p = 0.04) and memory cells (21.1-14.1% for LPV/r versus 20.2-17.9% for continuation arm, NSS). Switching patients to an LPV/r-containing regimen improved CD4(+) counts in patients with prior immunologic failure, and this may be due to an effect of LPV/r on apoptosis.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Pirimidinonas/administração & dosagem , Ritonavir/administração & dosagem , Adulto , Contagem de Linfócito CD4 , Feminino , HIV-1/isolamento & purificação , Humanos , Lopinavir , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Resultado do Tratamento , Carga Viral
3.
Gen Comp Endocrinol ; 166(2): 365-71, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20036667

RESUMO

Despite the importance of the western white-bearded wildebeest (Connochaetes taurinus mearnsi) to the Serengeti-Mara ecosystem, surprisingly little is known about the reproductive physiology of this keystone species. A longitudinal, non-invasive endocrine study was conducted on female wildebeest captured from the Serengeti-Mara migration and maintained for approximately 16 months in large fenced enclosures within the species' natural range. An intact bull was introduced to a female subgroup (n=5), while remaining females (n=10) were unexposed to a male. Fecal progestagen patterns reflected ovarian activity and pregnancy. In non-pregnant animals, luteal and inter-luteal baseline progestagen values differed (p<0.001) over time, thereby allowing identification of recurrent estrous cycles. The average durations of the luteal phase, estrous cycle, gestation, and post-partum anestrus were 14.3+/-0.5, 22.6+/-1.0, 240.8+/-11.7, and 104.1+/-15.6 d, respectively. Annual reproductive patterns indicated a distinctive period of ovarian activity that extended from 13 May through 3 December (203.5+/-29.9 d) with all unmated females displaying from one to 14 estrous cycles. Progestagens were higher (p <0.001) in pregnant (n=4) than non-pregnant (n=10) cows. These data (1) reveal the value of fecal hormone monitoring for establishing the first ever endocrine profiles of female wildebeest in semi-free-living conditions in their native range, and (2) indicate that the species is a seasonal breeder that is polyestrous and a spontaneous ovulator.


Assuntos
Ciclo Estral/metabolismo , Progestinas/metabolismo , Reprodução/fisiologia , Ruminantes/metabolismo , Animais , Cruzamento , Ecossistema , Fezes/química , Feminino , Quênia , Lactação , Fase Luteal/metabolismo , Masculino , Parto , Gravidez , Progestinas/análise , Estações do Ano , Tanzânia
4.
J Clin Microbiol ; 45(7): 2105-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17507510

RESUMO

Clinical presentations for viral respiratory tract infections are often nonspecific, and a rapid, high-throughput laboratory technique that can detect a panel of common viral pathogens is clinically desirable. We evaluated two multiplex reverse transcription-PCR (RT-PCR) products coupled with microarray-based systems for simultaneous detection of common respiratory tract viral pathogens. The NGEN respiratory virus analyte-specific assay (Nanogen, San Diego, CA) detects influenza A virus (Flu-A) and Flu-B, parainfluenza virus 1 (PIV-1), PIV-2, and PIV-3, and respiratory syncytial virus (RSV), while the ResPlex II assay (Genaco Biomedical Products, Inc., Huntsville, AL) detects Flu-A, Flu-B, PIV-1, PIV-2, PIV-3, PIV-4, RSV, human metapneumovirus (hMPV), rhinoviruses (RhVs), enteroviruses (EnVs), and severe acute respiratory syndrome (SARS) coronavirus (CoV). A total of 360 frozen respiratory specimens collected for a full year were tested, and results were compared to those obtained with a combined reference standard of cell culture and monoplex real-time TaqMan RT-PCR assays. NGEN and ResPlex II gave comparable sensitivities for Flu-A (82.8 to 86.2%), Flu-B (90.0 to 100.0%), PIV-1 (87.5 to 93.8%), PIV-3 (66.7 to 72.2%), and RSV (63.3 to 73.3%); both assays achieved excellent specificities (99.1 to 100.0%) for these five common viruses. The ResPlex II assay detected hMPV in 13 (3.6%) specimens, with a sensitivity of 80.0% and specificity of 99.7%. The ResPlex II assay also differentiated RSV-A and RSV-B and gave positive results for RhV and EnV in 31 (8.6%) and 19 (5.3%) specimens, respectively. PIV-2, PIV-4, and SARS CoV were not detected in the specimens tested. The two systems can process 80 (NGEN) and 96 (ResPlex II) tests per run, with a hands-on time of approximately 60 min and test turnaround times of 6 h (ResPlex II) and 9 h (NGEN). Multiple-panel testing detected an additional unsuspected 9 (3.4%) PIV-1 and 10 (3.7%) PIV-3 infections. While test sensitivities for RSV and PIV-3 need improvement, both the NGEN and ResPlex II assays provide user-friendly and high-throughput tools for simultaneous detection and identification of a panel of common respiratory viral pathogens in a single test format. The multiplex approach enhances diagnosis through detection of respiratory viral etiologic agents in cases in which the presence of the agent was not suspected and a test was not ordered by the clinicians.


Assuntos
Infecções por Vírus de RNA/virologia , Vírus de RNA/isolamento & purificação , Doenças Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Viroses/virologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Vírus de RNA/classificação
5.
Tunis Med ; 79(2): 65-81, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11414062

RESUMO

Intracellular diseases are difficult to treat and constitute a major problem for modern medicine. In this type of diseases, a TH-1 immune response favors protection, while a TH-2 response is detrimental to the host. Current vaccines are using antigens to initiate an immune response regardless of its nature and its mechanism. New vaccines are designed to combine selected antigens with potent adjuvants to stimulate the appropriate pathway of the immune system and deliver a lasting protective immunity. The Mycobacterium recombinant vaccine system for treatment of intracellular diseases utilizes antigen delivery systems in the form of non pathogenic Mycobacterium strains, genetic transfer systems in the form of cloning and expression vectors, and related technologies to provide products containing non toxic immuno-regulating Mycobacterium adjuvants, non toxic immuno-stimulating exogenous antigens specific for a variety of diseases, and non toxic amounts of cytokines that boost the TH-1 pathway. The cloning and expression Mycobacterium vectors include both pAL5000-based extra-chromosomal and D29-based integrative vectors.


Assuntos
Vacinas Bacterianas/imunologia , Mycobacterium/imunologia , Vacinas Sintéticas/imunologia , Adjuvantes Imunológicos , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Vacinas Bacterianas/uso terapêutico , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Infecções/imunologia , Infecções/terapia , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T/imunologia , Vacinas Sintéticas/uso terapêutico
6.
Int J Parasitol ; 29(9): 1351-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10579423

RESUMO

Associations between Human Leukocyte Antigen (HLA) (i.e. human major histocompatibility complex [MHC]) genes and susceptibility to infections and inflammatory processes have been described, but causal relationships have not been proven. We characterized effects of HLA-DQ alleles on outcome of congenital toxoplasma infection and found that among Caucasians, the DQ3 gene frequency was significantly higher in infected infants with hydrocephalus (0.783) than infected infants without hydrocephalus (0.444) or published normal controls (0.487). We then developed a novel animal model to definitively determine the effect of these HLA DQ molecules on the severity of toxoplasmosis. Human MHC-Class II transgenes reduced parasite burden and necrosis in brains of mice infected with Toxoplasma gondii. Consistent with the observed association between DQ3 and hydrocephalus in human infants, in the murine model the DQ3(DQ8; DQB1*0302) gene protected less than DQ1 (DQ6; DQB1*0601). Our findings definitively prove a cause and effect relationship between human MHC genes and resistance to infection, provide novel means to characterise human immune responses that are protective or pathogenic in infections, and are important for vaccine development.


Assuntos
Antígenos HLA-DQ/genética , Hidrocefalia/imunologia , Toxoplasmose Congênita/imunologia , Animais , Encéfalo/patologia , Feminino , Frequência do Gene , Genes MHC da Classe II , Homozigoto , Humanos , Hidrocefalia/complicações , Hidrocefalia/diagnóstico , Lactente , Transmissão Vertical de Doenças Infecciosas , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Transgênicos , Grupos Raciais , Toxoplasmose Congênita/complicações , Toxoplasmose Congênita/diagnóstico
7.
Antimicrob Agents Chemother ; 42(8): 2036-40, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9687403

RESUMO

Addition of paclitaxel (Taxol) at a concentration of 1 microM to Toxoplasma gondii-infected human foreskin fibroblasts arrested parasite multiplication. Division of the T. gondii tachyzoite nucleus was inhibited, leading to syncytium-like parasite structures within the fibroblasts by 24 h after infection and treatment of the cultures. By 4 days after infection and treatment of the cultures with paclitaxel, this inhibition was irreversible, since the arrested intracellular form was incapable of leaving the host cell, infecting new cells, and initiating the growth of tachyzoites with normal morphology. Specifically, when paclitaxel was added to infected cells for 4 days and then removed by washing and the infected, paclitaxel-treated cells were cultured for 4 more days, there were no remaining T. gondii organisms with normal morphology. Syncytium-like structures in the cultures that were infected and treated with paclitaxel for 8 days were similar in appearance to those in preparations of infected paclitaxel-treated fibroblasts that had been cultured for 24 to 48 h. Pretreatment of the tachyzoites for 1 h with paclitaxel followed by the removal of the paclitaxel by repeatedly centrifuging and resuspending the parasites in fresh medium without paclitaxel and then adding fresh medium prior to culture of the parasites with fibroblasts did not prevent their invasion of fibroblasts but did affect their subsequent ability to replicate within fibroblasts. Pretreatment of the fibroblasts with paclitaxel also diminished subsequent replication of T. gondii in such host cells after 8 days. Thus, paclitaxel alters the ability of T. gondii to replicate in host cells. Inhibition of parasite microtubules by such compounds at concentrations which do not interfere with the function of host cell microtubules may be useful for development of novel medicines to treat T. gondii infections in the future.


Assuntos
Paclitaxel/farmacologia , Toxoplasma/efeitos dos fármacos , Animais , DNA/biossíntese , Humanos , Toxoplasma/crescimento & desenvolvimento
9.
Immunology ; 85(3): 419-28, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7558130

RESUMO

Control of resistance to cyst burden following per-oral infection with Toxoplasma gondii has been mapped previously to a region of mouse chromosome 17 of approximately 140 kb. This region is contiguous with and contains the class I gene, Ld. Resistance to development of toxoplasmic encephalitis has also been reported to be controlled by genes in this region of H-2. TNF-alpha, D and L genes, as well as unidentified genes, are also in this region. The work described here was performed to identify definitively the gene(s) in this 140 kb region that confers resistance to cysts and encephalitis. The study demonstrates that relative resistance to T. gondii organisms and cyst burden in brain, and toxoplasmic encephalitis, 30 days following per-oral T. gondii infection is correlated absolutely with the presence of the Ld gene in inbred, recombinant, mutant and C3H.Ld transgenic mice. Mice with the Ld gene had lower cyst burdens and less encephalitis than those without the Ld gene. Specifically, 30 days after infection mice with the Ld gene had minimal perivascular inflammation and meningeal inflammation and very few Toxoplasma cysts or organisms in immunoperoxidase-stained preparations of their brains. Mice without the Ld gene had a similar pattern of inflammation, but in addition they had collections of inflammatory cells in the brain parenchyma. Free tachyzoites were found within these foci of inflammation and cysts were present in these areas as well as in contiguous areas without inflammatory cells. There were CD4+ and CD8+ T lymphocytes in the areas of inflammation and throughout the brain parenchyma. Mice that were resistant to cysts and encephalitis had little detectable brain cytokine mRNA expression, while mice that were susceptible had elevated levels of mRNA for a wide range of cytokines, consistent with their greater amounts of inflammation. The present work definitively demonstrates that a Ld-restricted response decreases the number of organisms and cysts within the brain and thereby limits toxoplasmic encephalitis and levels of interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), IL-6, IL-10, transforming growth factor-beta (TGF-beta), IL-1 alpha, IL1 beta and macrophage inhibiting protein (MIP) mRNA in the brain 30 days after per-oral infection.


Assuntos
Encefalite/genética , Antígenos H-2/genética , Toxoplasmose Animal/genética , Toxoplasmose Cerebral/genética , Animais , Encéfalo/parasitologia , Citocinas/biossíntese , Citocinas/genética , Encefalite/imunologia , Feminino , Imunidade Inata/genética , Camundongos , Camundongos Endogâmicos , RNA Mensageiro/genética , Especificidade da Espécie , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/patologia , Toxoplasmose Cerebral/imunologia , Toxoplasmose Cerebral/patologia
11.
Intensive Care Med ; 21(4): 365-83, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7650262

RESUMO

Ventilator-associated pneumonia (VAP) is an infection of the lung parenchyma developing in patients on mechanical ventilation for more than 48 h. VAP is associated with a remarkably constant spectrum of pathogenic bacteria, most of which are aerobic Gram-negative bacilli (AGNB) and, to a lesser extent Staphyloccus aureus. Most authorities agree that VAP develops as a result of aspiration of secretions contaminated with pathogenic organisms, which appear to be endogenously acquired. These pathogens gain access to the distal airways by mechanical reflux and aspiration of contaminated gastric contents and also by repetitive inoculation of contaminated upper airway secretions into the distal tracheobronchial tree. Persistence of these organisms in the upper airways involves their successful colonization of available surfaces. Although exogenous acquisition can occur from the environment, the rapidity at which critically ill patients acquire AGNB in the upper airways in conjunction with the low rate of AGNB colonization of health-care workers exposed to the same environment favors the presence of endogenous proximate sources of AGNB and altered upper airway surfaces that are rendered receptive. Proximate sources of AGNB remain unclear, but potential sites harboring AGNB prior to illness include the upper gastrointestinal tract, subgingival dental plaque, and the periodontal spaces. Following illness or antibiotic therapy, competitive pressures within the oropharynx favor AGNB adherence to epithelial cells, which lead to oropharyngeal colonization. Similar dynamic changes in contiguous structures (oropharynx, trachea, sinuses, and the upper gastrointestinal tract) lead to the transcolonization of these structures with pathogenic bacteria. Following local colonization or infection, these structures serve as reservoirs of AGNB capable of inoculating the lower airways. As the oropharynx becomes colonized with AGNB, contaminated oropharyngeal secretions reach the trachea, endotracheal tube, and ventilator circuit. Contaminated secretions pooled above the endotracheal tube cuff gain access to the trachea and inner lumen of the endotracheal tube by traversing endotracheal tube cuff folds. Amorphic particulate deposits containing AGNB form along the endotracheal tube and are capable of being propelled into the distal airways by ventilator-generated airflow or by tubing manipulation. Bacteria embedded within this type of amorphous matrix are particularly difficult for the host to clear. If host defenses fail to clear the inoculum, then bacterial proliferation occurs, and the host inflammatory response progresses to bronchopneumonia.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Infecção Hospitalar/microbiologia , Pneumonia Bacteriana/microbiologia , Respiração Artificial/efeitos adversos , Aderência Bacteriana , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Contaminação de Equipamentos , Humanos , Pneumonia Aspirativa , Pneumonia Bacteriana/prevenção & controle , Pneumonia Bacteriana/transmissão
13.
J Biol Chem ; 269(31): 20139-48, 1994 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-8051102

RESUMO

Protein phosphatase 2A (PP2A) is composed of structural (A), catalytic (C), and regulatory subunits (B). Immunological analyses identified B alpha/PR55 alpha as the major regulatory subunit of brain PP2A while a unique B' subunit was associated with the cardiac enzyme. Recombinant PP2A heterotrimers were purified from insect cells infected with baculoviruses expressing A and C, in combination with viruses expressing B alpha/PR55 alpha, B beta/PR55 beta, or SV40 small tumor antigen (st). Phosphatase activities of rAC-B alpha and rAC-B beta were similar to those for brain AC-B alpha, while rAC-st was 50-80% less active. Heparin had no effect on rAC-st myosin light chain phosphatase activity, while the B subunit-containing forms were stimulated 2-3-fold. Protamine caused a 3-4-fold increase in AC-B alpha and rAC-st activities and a marked activation of rAC-B beta (6-fold) and AC-B' (10.5-fold). When histone H1 was used as substrate, all of the heterotrimers were stimulated approximately 4-fold by heparin. The activity of AC-B' and rAC-B beta were increased 2-fold by Mn2+, while a 6-fold stimulation was observed with rAC-st. Chemical cross-linking of AC-B alpha and AC-B beta generated 200-kDa complexes, while AC-st was present as a 150-kDa complex. These results demonstrate that different regulatory proteins affect enzyme activity and the response to agents that modify PP2A activity in vitro. Different PP2A heterotrimers are likely to have distinct functions in vivo, and changes in subunit composition will have an important impact on signal transduction pathways.


Assuntos
Isoenzimas/química , Fosfoproteínas Fosfatases/química , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Sequência de Bases , Sítios de Ligação , Encéfalo/enzimologia , Bovinos , Linhagem Celular , Clonagem Molecular , Reagentes de Ligações Cruzadas , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Humanos , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Dados de Sequência Molecular , Mariposas , Miocárdio/enzimologia , Fosfoproteínas Fosfatases/isolamento & purificação , Fosfoproteínas Fosfatases/metabolismo , Proteína Fosfatase 2 , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
14.
J Biol Chem ; 267(30): 21864-72, 1992 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-1328247

RESUMO

The alpha form of the A subunit of human protein phosphatase 2A was expressed in insect cells following infection with a recombinant baculovirus. A alpha was expressed as a soluble protein that comprised approximately 10% of total cellular protein. The expressed A alpha subunit was purified by chromatography on amino-hexyl-Sepharose and Mono Q with a yield of 2 mg/500-ml culture. The recombinant protein had the same apparent molecular mass as the bovine cardiac protein and was devoid of myosin light chain phosphatase activity. Biological activity of expressed A was assessed by assays of complex formation with the catalytic (C) and B subunits, purified from bovine cardiac tissue, and by inhibition of phosphatase activity. Purified A alpha had a high apparent affinity for C (IC50 = 0.10 nM) and bound with a stoichiometry of 1 mol of A/mol of C. Interaction of A alpha with the catalytic subunit caused a maximal inhibition of myosin light chain and phosphorylase phosphatase activities of 50 and 79%, respectively. The AC complex prepared by reconstitution of recombinant A alpha with C had the same electrophoretic mobility in nondenaturing polyacrylamide gels and the same elution volume when chromatographed on a size exclusion column as the native AC complex purified from cardiac muscle. Similar chromatographic profiles were also observed for the heterotrimer reconstituted from recombinant A alpha, purified B and C, and the native bovine cardiac heterotrimeric holoenzyme. Cross-linking of the native enzyme and the reconstituted heterotrimer generated the same pattern of high molecular weight species. Immunological analyses of these complexes demonstrated that distinct cross-linked forms composed of ABC, AC, AB, and BC were obtained. These results suggest that each of the three subunits of protein phosphatase 2A forms direct contacts with both of the others.


Assuntos
Fosfoproteínas Fosfatases/biossíntese , Animais , Baculoviridae , Catálise , Bovinos , Células Cultivadas , Cromatografia em Gel , Clonagem Molecular , Reagentes de Ligações Cruzadas , DNA , Humanos , Miocárdio/enzimologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Proteína Fosfatase 2 , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
15.
Death Stud ; 16(1): 1-15, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-10117181

RESUMO

We sought to identify variables that contribute to euthanasia attitude and behavior, including demographics, death fears, experience with death, attitudes toward patient autonomy, and level of moral development. Subjects were 137 registered nurses from the southeastern United States representing 13 clinical nursing areas. Principal components analysis identified four factors that together explained 62.9% of total variance. These factors were belief in afterlife, nursing experience, liberal or conservative political view, and personal values. Variables identified through factor analysis were entered into regression analyses. These analyses showed that increased religious belief, years of nursing experience, and propensity to view death as an end of existence predicted opposition to euthanasia. Predictors for euthanasia support included a liberal political view, more experience with dying patients, and the belief that patients should have a personal responsibility for their own health-care decisions.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Morte , Eutanásia/estatística & dados numéricos , Enfermeiras e Enfermeiros/psicologia , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Coleta de Dados , Eutanásia Ativa Voluntária , Liberdade , Humanos , Desenvolvimento Moral , Princípios Morais , Enfermeiras e Enfermeiros/estatística & dados numéricos , Autonomia Pessoal , Política , Análise de Regressão , Religião , South Carolina , População Branca/psicologia , População Branca/estatística & dados numéricos
16.
Chest ; 100(4): 943-52, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1914609

RESUMO

Most patients with adult respiratory distress syndrome (ARDS) survive the initial insult which caused respiratory failure only to succumb later to sepsis caused by nosocomial pneumonia or to pulmonary fibrosis. Clinical criteria and analysis of the tracheal aspirate are notoriously inadequate for establishing a diagnosis of ventilator-associated pneumonia. We implemented a comprehensive diagnostic protocol to determine the cause of sepsis in ARDS patients who had been ventilated for more than three days and who had no bronchoscopic evidence of pneumonia. Nine patients with late ARDS who had fever (89 percent), leukocytosis (89 percent), a new localized infiltrate (78 percent), purulent tracheal secretions (89 percent), low systemic vascular resistance (50 percent), and marked uptake of gallium in the lungs (100 percent) had no source of infection identified. Open-lung biopsy specimens from seven patients showed the fibroproliferative phase of diffuse alveolar damage and confirmed absence of pneumonia. Treatment with prolonged high doses of corticosteroids was associated with a marked and rapid improvement in lung injury score (p less than 0.003 at five days). Our findings indicate that the fibroproliferative process occurring in the lungs of patients with late ARDS gives rise to clinical manifestations identical to those of pneumonia and is potentially responsive to steroid treatment.


Assuntos
Pulmão/patologia , Hemissuccinato de Metilprednisolona/uso terapêutico , Fibrose Pulmonar/patologia , Síndrome do Desconforto Respiratório/complicações , Adulto , Biópsia , Infecção Hospitalar/diagnóstico , Diagnóstico Diferencial , Feminino , Febre de Causa Desconhecida/etiologia , Humanos , Leucocitose/etiologia , Masculino , Projetos Piloto , Pneumonia/diagnóstico , Fibrose Pulmonar/complicações , Síndrome do Desconforto Respiratório/tratamento farmacológico
17.
J Biol Chem ; 266(20): 13251-60, 1991 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-1649186

RESUMO

Protein phosphatase 2A consists of a heterotrimeric complex composed of a catalytic subunit (C) and two associated subunits (A and B). Limited tryptic digestion of the heterotrimeric ABC form resulted in the selective degradation of the Mr = 55,000 B subunit to a 48-kDa polypeptide. The cleavage sites were determined to be within a 3-7-kDa region of the COOH terminus. Proteolysis led to dissociation of the B subunit from the enzyme complex and correlated with an increase in cardiac myosin light chain, smooth muscle myosin light chain peptide, and Leu-Arg-Arg-Ala-Ser-Leu-Gly (Kemptide) phosphatase activity. Purification of the digestion products and native gel electrophoresis indicated that dissociation of the B subunit was responsible for the increase in phosphatase activity. Kinetic analyses with several substrates revealed that dissociation of the B subunit resulted in a 2-7-fold increase in Vmax and a 1.6-5 fold increase in Km. Proteolytic dissociation of the B subunit increased the sensitivity of protein phosphatase 2A to inhibition by okadaic acid. Inhibition of the trypsinized enzyme was very similar to that observed for the purified AC form of protein phosphatase 2A. Incubation of the ABC complex with N-ethylmaleimide resulted in dissociation of the C subunit and generation of an AB complex. Selective release of the C subunit indicated that the B subunit interacts directly with the A subunit and that one or more free sulfhydryls are required to maintain the heterotrimeric structure of protein phosphatase 2A. Treatment of the enzyme with heparin resulted in an increase in specific activity that was due to the release of the B subunit from the complex. These results provide evidence that the B subunit binds directly to the A subunit to modulate enzyme activity and substrate specificity and that the COOH-terminal region of this protein is important for interaction with the AC complex. Dissociation of the B subunit by polyanionic substances related to heparin may represent a mechanism for regulating the activity of this enzyme.


Assuntos
Etilmaleimida/farmacologia , Heparina/farmacologia , Fosfoproteínas Fosfatases/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Soros Imunes , Immunoblotting , Cinética , Substâncias Macromoleculares , Dados de Sequência Molecular , Peso Molecular , Miocárdio/enzimologia , Quinase de Cadeia Leve de Miosina/metabolismo , Fragmentos de Peptídeos/isolamento & purificação , Peptídeos/síntese química , Peptídeos/imunologia , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/isolamento & purificação , Proteína Fosfatase 2 , Especificidade por Substrato , Tripsina/metabolismo
18.
Mol Cell Biol ; 11(4): 1988-95, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1706474

RESUMO

Soluble, monomeric simian virus 40 (SV40) small-t antigen (small-t) was purified from bacteria and assayed for its ability to form complexes with protein phosphatase 2A (PP2A) and to modify its catalytic activity. Different forms of purified PP2A, composed of combinations of regulatory subunits (A and B) with a common catalytic subunit (C), were used. The forms used included free A and C subunits and AC and ABC complexes. Small-t associated with both the free A subunit and the AC form of PP2A, resulting in a shift in mobility during nondenaturing polyacrylamide gel electrophoresis. Small-t did not interact with the free C subunit or the ABC form. These data demonstrate that the primary interaction is between small-t and the A subunit and that the B subunit of PP2A blocks interaction of small-t with the AC form. The effect of small-t on phosphatase activity was determined by using several exogenous substrates, including myosin light chains phosphorylated by myosin light-chain kinase, myelin basic protein phosphorylated by microtubule-associated protein 2 kinase/ERK1, and histone H1 phosphorylated by protein kinase C. With the exception of histone H1, small-t inhibited the dephosphorylation of these substrates by the AC complex. With histone H1, a small stimulation of dephosphorylation by AC was observed. Small-t had no effect on the activities of free C or the ABC complex. A maximum of 50 to 75% inhibition was obtained, with half-maximal inhibition occurring at 10 to 20 nM small-t. The specific activity of the small-t/AC complex was similar to that of the ABC form of PP2A with myosin light chains or histone H1 as the substrate. These results suggested that small-t and the B subunit have similar qualitative and quantitative effects on PP2A enzyme activity. These data show that SV40 small-antigen binds to purified PP2A in vitro, through interaction with the A subunit, and that this interaction inhibits enzyme activity.


Assuntos
Antígenos Virais de Tumores/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Vírus 40 dos Símios/imunologia , Animais , Bovinos , Histonas/metabolismo , Manganês/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Mariposas , Proteína Básica da Mielina/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Proteínas Quinases/metabolismo , Proteína Fosfatase 2 , Especificidade por Substrato
19.
Endocrinology ; 127(1): 63-8, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1694500

RESUMO

Extensive remodeling of the follicular extracellular matrix occurs during the process of ovulation. This remodeling involves the breakdown of collagen, which is regulated, in part, by the action of the metalloproteinase collagenase and its associated inhibitors. In the present study, follicular metalloproteinase inhibitors were characterized to determine whether they were serum-borne or of ovarian origin, possibly a tissue-derived inhibitor known as tissue inhibitor of metalloproteinase (TIMP). Human follicular fluid and granulosa cells were obtained from preovulatory follicles of patients in an in vitro fertilization program. Chromatographic separation of follicular fluid on Sepharose 6B resulted in two peaks of inhibitory activity. The large molecular radius (Mr) inhibitor was similar in size to the serum-borne metalloproteinase inhibitor alpha 2-macroglobulin (i.e. Mr 700,000) whereas the small Mr inhibitor approximated the size of TIMP (i.e. Mr 29,000). Incubation of aliquots from either of the two peaks of inhibitor activity or an alpha 2-macroglobulin standard with an antibody to alpha 2-macroglobulin decreased the inhibitory activity in both the large Mr peak and the alpha 2-macroglobulin standard by 86.6 +/- 1.7% and 71.5 +/- 7.7% (n = 4, P less than 0.005), respectively, implying cross-reactivity with the alpha 2-macroglobulin antibody. The inhibitory activity in the small Mr peak, however, was unchanged. Northern analysis of total granulosa cell RNA demonstrated TIMP messenger RNA (mRNA) in all eight granulosa cell samples examined whereas alpha 2-macroglobulin mRNA was virtually undetectable. A positive correlation (r = 0.85, P less than 0.01) was observed between the levels of TIMP mRNA and the ratio of the follicular estradiol-progesterone concentration. However, inhibitor activity in the follicular fluid was not correlated with the levels of TIMP mRNA (r = 0.05). These findings confirm the presence of alpha 2-macroglobulin in follicular fluid and demonstrate that human preovulatory granulosa cells contain mRNA for TIMP, an inhibitor that regulates metalloproteinases such as collagenase, gelatinase, and proteoglycanase. Additionally, the expression of TIMP mRNA is steroid related and may be hormonally regulated. It is proposed that TIMP produced in the granulosa cell compartment in conjunction with alpha 2-macroglobulin from the serum may act to control the site and extent of ovarian connective tissue remodeling.


Assuntos
Glicoproteínas/isolamento & purificação , Metaloendopeptidases/antagonistas & inibidores , Ovário/análise , Ovulação/fisiologia , alfa-Macroglobulinas/análise , Anticorpos/farmacologia , Estradiol/análise , Feminino , Líquido Folicular/análise , Glicoproteínas/genética , Glicoproteínas/farmacologia , Células da Granulosa/análise , Humanos , Peso Molecular , Progesterona/análise , RNA Mensageiro/análise , Inibidores Teciduais de Metaloproteinases , alfa-Macroglobulinas/imunologia
20.
Percept Mot Skills ; 69(3 Pt 1): 1037-8, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2608382

RESUMO

Further comment and analyses of data from 103 alcoholics indicate less internal consistency in alcoholics' responding than in normals, no tendency for innovative alcoholics to engage in more hostile/aggressive behaviors than adaptor alcoholics, and a likelihood that more than three factors for alcoholics would be required to account for variance comparable to that for nonalcoholic persons.


Assuntos
Alcoolismo/psicologia , Testes de Personalidade , Adaptação Psicológica , Criatividade , Humanos , Psicometria , Conformidade Social
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