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1.
Lett Appl Microbiol ; 76(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906280

RESUMO

Efficacy of cleaning methods against SARS-CoV-2 suspended in either 5% soil load (SARS-soil) or simulated saliva (SARS-SS) was evaluated immediately (hydrated virus, T0) or 2 hours post-contamination (dried virus, T2). Hard water dampened wiping (DW) of surfaces, resulted in 1.77-3.91 log reduction (T0) or 0.93-2.41 log reduction (T2). Incorporating surface pre-wetting by spraying with a detergent solution (D + DW) or hard water (W + DW) just prior to dampened wiping did not unilaterally increase efficacy against infectious SARS-CoV-2, however, the effect was nuanced with respect to surface, viral matrix, and time. Cleaning efficacy on porous surfaces (seat fabric, SF) was low. W + DW on stainless steel (SS) was as effective as D + DW for all conditions except SARS-soil at T2 on SS. DW was the only method that consistently resulted in > 3-log reduction of hydrated (T0) SARS-CoV-2 on SS and ABS plastic. These results suggest that wiping with a hard water dampened wipe can reduce infectious virus on hard non-porous surfaces. Pre-wetting surfaces with surfactants did not significantly increase efficacy for the conditions tested. Surface material, presence or absence of pre-wetting, and time post-contamination affect efficacy of cleaning methods.


Assuntos
COVID-19 , Vírus , Humanos , SARS-CoV-2 , Desinfecção/métodos , Detergentes/farmacologia , Tato , COVID-19/prevenção & controle , Água
2.
J Occup Environ Hyg ; 19(8): 455-468, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35687041

RESUMO

The list of EPA-approved disinfectants for coronavirus features many products for use on hard, non-porous materials. There are significantly fewer products registered for use on porous materials. Further, many common, high-touch surfaces fall in between non-porous materials such as glass and porous materials such as soft fabrics. The objective of this study was to assess the efficacy of selected commercially available disinfectant products against coronaviruses on common, high-touch surfaces. Four disinfectants (Clorox Total 360, Bleach solution, Vital Oxide, and Peroxide Multi-Surface Cleaner) were evaluated against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV in cell culture medium was inoculated onto four materials: stainless steel, latex-painted drywall tape, Styrene Butadiene rubber (rubber), and bus seat fabric. Immediately (T0) or 2-hr (T2) post-inoculation, disinfectants were applied by trigger-pull or electrostatic sprayer and either held for recommended contact times (Spray only) or immediately wiped (Spray and Wipe). Recovered infectious MHV was quantified by median tissue culture infectious dose assay. Bleach solution, Clorox Total 360, and Vital Oxide were all effective (>3-log10 reduction or complete kill of infectious virus) with both the Spray Only and Spray and Wipe methods on stainless steel, rubber, and painted drywall tape when used at recommended contact times at both T0 and T2 hr. Multi-Surface Cleaner unexpectedly showed limited efficacy against MHV on stainless steel within the recommended contact time; however, it showed increased (2.3 times greater efficacy) when used in the Spray and Wipe method compared to Spray Only. The only products to achieve a 3-log10 reduction on fabric were Vital Oxide and Clorox Total 360; however, the efficacy of Vital Oxide against MHV on fabric was reduced to below 3-log10 when applied by an electrostatic sprayer compared to a trigger-pull sprayer. This study highlights the importance of considering the material, product, and application method when developing a disinfection strategy for coronaviruses on high-touch surfaces.


Assuntos
COVID-19 , Desinfetantes , Vírus da Hepatite Murina , Animais , Desinfetantes/farmacologia , Desinfecção/métodos , Camundongos , Borracha/farmacologia , SARS-CoV-2 , Hipoclorito de Sódio/farmacologia , Aço Inoxidável/farmacologia
4.
Science ; 285(5436): 2126-9, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10497130

RESUMO

Cell proliferation requires cell growth; that is, cells only divide after they reach a critical size. However, the mechanisms by which cells grow and maintain their appropriate size have remained elusive. Drosophila deficient in the S6 kinase gene (dS6K) exhibited an extreme delay in development and a severe reduction in body size. These flies had smaller cells rather than fewer cells. The effect was cell-autonomous, displayed throughout larval development, and distinct from that of ribosomal protein mutants (Minutes). Thus, the dS6K gene product regulates cell size in a cell-autonomous manner without impinging on cell number.


Assuntos
Drosophila melanogaster/enzimologia , Drosophila melanogaster/crescimento & desenvolvimento , Proteínas Quinases S6 Ribossômicas/metabolismo , Asas de Animais/citologia , Animais , Sequência de Bases , Constituição Corporal , Contagem de Células , Divisão Celular , Tamanho Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Células Epiteliais/citologia , Feminino , Genes de Insetos , Larva/citologia , Larva/crescimento & desenvolvimento , Masculino , Metamorfose Biológica , Dados de Sequência Molecular , Mutação , Proteínas Quinases S6 Ribossômicas/genética , Asas de Animais/crescimento & desenvolvimento
5.
Science ; 288(5473): 2045-7, 2000 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-10856218

RESUMO

Because ribosome biogenesis plays an essential role in cell proliferation, control mechanisms may have evolved to recognize lesions in this critical anabolic process. To test this possibility, we conditionally deleted the gene encoding 40S ribosomal protein S6 in the liver of adult mice. Unexpectedly, livers from fasted animals deficient in S6 grew in response to nutrients even though biogenesis of 40S ribosomes was abolished. However, liver cells failed to proliferate or induce cyclin E expression after partial hepatectomy, despite formation of active cyclin D-CDK4 complexes. These results imply that abrogation of 40S ribosome biogenesis may induce a checkpoint control that prevents cell cycle progression.


Assuntos
Divisão Celular , Fígado/citologia , Fígado/fisiologia , Biossíntese de Proteínas , Proteínas Proto-Oncogênicas , Proteínas Ribossômicas/fisiologia , Animais , Ciclina D1/biossíntese , Ciclina D1/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Quinases Ciclina-Dependentes/metabolismo , DNA/biossíntese , Privação de Alimentos , Fase G1 , Deleção de Genes , Marcação de Genes , Hepatectomia , Interferon-alfa/farmacologia , Fígado/metabolismo , Regeneração Hepática , Camundongos , Camundongos Endogâmicos , Fosforilação , Polirribossomos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Ribossômico/metabolismo , Proteína S6 Ribossômica , Proteínas Ribossômicas/genética , Ribossomos/metabolismo , Fase S
6.
Eur J Echocardiogr ; 9(5): 646-54, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18296398

RESUMO

AIMS: To determine the feasibility of strain rate imaging (SRI) in the objective detection of exercise-induced ischaemia. METHODS AND RESULTS: Sixteen patients undergoing elective percutaneous coronary intervention (PCI) underwent treadmill exercise stress echocardiography (ESE) pre- and post-PCI. Measurement of systolic SRI parameters was attempted in all myocardial segments at baseline, peak stress, and in recovery. Segments were divided into those supplied by target (Group 1) and non-target vessels (Group 2). Percutaneous coronary intervention was successful in all patients. In Group 1, there was no significant difference in post-systolic strain rate (SRps) at baseline or at peak stress but there was significantly greater SRps pre-PCI compared with post-PCI at 30 min into recovery (-0.37 +/- 0.53 vs. -0.07 +/- 0.44 s(-1), P = 0.004). There were similar findings with the SRps index [ratio of SRps:peak systolic strain rate (SRsys)]. Group 2 segments did not demonstrate any significant differences in SRI parameters pre- and post-PCI. At peak exercise pre-PCI, Group 1 segments had significantly delayed time to SRsys compared with Group 2 (0.12 +/- 0.05 vs. 0.09 +/- 0.05 s, P = 0.013), a difference that was abolished post-PCI. CONCLUSION: This suggests a potential role for SRI in the objective detection of exercise-induced ischaemia by echocardiography at peak stress and during recovery at the time of improved image quality.


Assuntos
Angioplastia Coronária com Balão , Ecocardiografia sob Estresse , Teste de Esforço , Tolerância ao Exercício , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/terapia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole , Fatores de Tempo
7.
Mol Cell Biol ; 13(4): 2524-35, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8384310

RESUMO

We have characterized two P-element-induced, lethal mutations in Drosophila melanogaster which affect the larval hemocytes, mediators of the insect immune response. Each mutant displays larval melanotic tumors characteristic of mutations affecting the insect cellular immune system, and the moribund animals develop grossly hypertrophied hematopoietic organs because of increased cell proliferation and extra rounds of endoreduplication in some hematopoietic cells. Surprisingly, these mutations are due to P element insertions in the 5' regulatory region of the Drosophila gene encoding ribosomal protein S6 and cause a reduction of S6 transcript abundance in mutant larvae.


Assuntos
Drosophila melanogaster/genética , Proteínas Ribossômicas/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Elementos de DNA Transponíveis , Drosophila melanogaster/citologia , Expressão Gênica , Regulação da Expressão Gênica , Genes de Insetos , Genes Letais , Células-Tronco Hematopoéticas/fisiologia , Humanos , Hibridização In Situ , Dados de Sequência Molecular , Mutagênese Insercional , Mutação , Oligodesoxirribonucleotídeos/química , RNA Mensageiro/genética , Ratos , Mapeamento por Restrição , Proteína S6 Ribossômica , Alinhamento de Sequência , Cromossomo X
8.
Mol Cell Biol ; 10(9): 5007-10, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2167445

RESUMO

A promoter sequence between nucleotide -51 and nucleotide -10 in the human alcohol dehydrogenase gene ADH2 has been shown to bind the transcription factor CCAAT/enhancer-binding protein (C/EBP). A series of 5'-end deletions of the ADH2 promoter was cotransfected with a C/EBP expression plasmid in a human hepatoma cell line, and trans activation by C/EBP was seen when at least 171 base pairs of 5'-flanking DNA was present. Mutations in the ADH2 promoter indicate that the mechanism of C/EBP trans activation involves two binding sites, one located just upstream of the TATA box and one located in an unusual location between the TATA box and the transcription start point.


Assuntos
Álcool Desidrogenase/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Enzimológica da Expressão Gênica , Regiões Promotoras Genéticas , Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma Hepatocelular , Linhagem Celular , Genes , Humanos , Neoplasias Hepáticas , Mutação , Transfecção
9.
Mol Cell Biol ; 11(3): 1638-46, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1996113

RESUMO

Retinoic acid regulation of one member of the human class I alcohol dehydrogenase (ADH) gene family was demonstrated, suggesting that the retinol dehydrogenase function of ADH may play a regulatory role in the biosynthetic pathway for retinoic acid. Promoter activity of human ADH3, but not ADH1 or ADH2, was shown to be activated by retinoic acid in transient transfection assays of Hep3B human hepatoma cells. Deletion mapping experiments identified a region in the ADH3 promoter located between -328 and -272 bp which confers retinoic acid activation. This region was also demonstrated to confer retinoic acid responsiveness on the ADH1 and ADH2 genes in heterologous promoter fusions. Within a 34-bp stretch, the ADH3 retinoic acid response element (RARE) contains two TGACC motifs and one TGAAC motif, both of which exist in RAREs controlling other genes. A block mutation of the TGACC sequence located at -289 to -285 bp eliminated the retinoic acid response. As assayed by gel shift DNA binding studies, the RARE region (-328 to -272 bp) of ADH3 bound the human retinoic acid receptor beta (RAR beta) and was competed for by DNA containing a RARE present in the gene encoding RAR beta. Since ADH catalyzes the conversion of retinol to retinal, which can be further converted to retinoic acid by aldehyde dehydrogenase, these results suggest that retinoic acid activation of ADH3 constitutes a positive feedback loop regulating retinoic acid synthesis.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Tretinoína/farmacologia , Sequência de Bases , Análise Mutacional de DNA , Humanos , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica , Transfecção , Tretinoína/metabolismo , Células Tumorais Cultivadas
10.
Mol Cell Biol ; 8(10): 4314-21, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3141788

RESUMO

We describe a Drosophila DNA clone of tandemly duplicated genes encoding an amino acid sequence nearly identical to human ribosomal protein S14 and yeast rp59. Despite their remarkably similar exons, the locations and sizes of introns differ radically among the Drosophila, human, and yeast (Saccharomyces cerevisiae) ribosomal protein genes. Transcripts of both Drosophila RPS14 genes were detected in embryonic and adult tissues and are the same length as mammalian S14 message. Drosophila RPS14 was mapped to region 7C5-9 on the X chromosome. This interval also encodes a previously characterized Minute locus, M(1)7C.


Assuntos
Drosophila melanogaster/genética , Proteínas Ribossômicas/genética , Cromossomo X , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Genes , Dados de Sequência Molecular , Família Multigênica , RNA Mensageiro/genética , Mapeamento por Restrição , Transcrição Gênica
11.
Postgrad Med J ; 83(977): 206-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17344578

RESUMO

PURPOSE: To evaluate the predictive value of N-terminal pro B-type natiuretic peptide (NT-proBNP) reference cut-off values as diagnostic markers for left ventricular systolic dysfunction (LVSD). STUDY DESIGN: A retrospective study assessing the use of NT-proBNP in the diagnostic algorithm for the investigation of patients with suspected signs and symptoms of LVSD presenting to primary care. RESULTS: A generic NT-proBNP cut-off (150 ng/l) value has similar negative and positive predictive valves, specificity and sensitivity compared to age and sex specific cut-off values. CONCLUSION: When using NT-proBNP as a triage tool for screening patients with signs and symptoms suggestive of LVSD, a simple generic cut-off level is as effective as more complex age sex specific cut-off values.


Assuntos
Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Disfunção Ventricular Esquerda/diagnóstico , Adulto , Idoso , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Aliment Pharmacol Ther ; 45(10): 1329-1338, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28318043

RESUMO

BACKGROUND: Transplacental transfer of infliximab and adalimumab results in detectable drug levels in the cord blood and infant. AIM: To determine if pregnancy influenced the pharmacokinetics of anti-TNF agents in women with inflammatory bowel disease. METHODS: Twenty-five women from the University of Calgary inflammatory bowel disease(IBD) pregnancy clinic on maintenance infliximab or adalimumab were recruited prospectively with serum bio-banking performed each trimester. Infliximab trough and adalimumab steady-state levels were the outcomes of interest and were analysed using the ANSER infliximab and adalimumab assays. Multivariate linear mixed-effects models were constructed to assess infliximab and adalimumab drug levels during pregnancy adjusting for the clinical covariates of albumin, BMI and CRP. RESULTS: Fifteen women (eight Crohn's disease, seven ulcerative colitis) received infliximab and 10 women with 11 pregnancies were treated with adalimumab. Median age was 29.6 years (IQR: 27.6-31.2 years). Median disease duration was 9.2 years (IQR: 3.16-15.0 years). Median trough infliximab concentrations were 8.50 µg/mL (IQR: 7.23-10.07 µg/mL), 10.31 µg/mL (IQR: 7.66-15.63 µg/mL) and 21.02 µg/mL (IQR: 16.01-26.70 µg/mL) at trimesters 1, 2 and 3 respectively. Significant changes in albumin and BMI (P < 0.05) but not CRP (P > 0.05) were documented throughout pregnancy. After adjusting for albumin, BMI and CRP, infliximab trough levels increased during pregnancy, by 4.2 µg/mL per trimester (P = 0.02), while adalimumab drug levels remained stable (P > 0.05). CONCLUSIONS: Infliximab levels rise during pregnancy, whereas adalimumab levels remain stable after accounting for changes in albumin, BMI and CRP. Therapeutic drug monitoring in the second trimester may be useful in guiding dosing in the third trimester.


Assuntos
Adalimumab/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Infliximab/farmacocinética , Troca Materno-Fetal , Adalimumab/farmacologia , Adalimumab/uso terapêutico , Adolescente , Adulto , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Monitoramento de Medicamentos , Feminino , Humanos , Infliximab/uso terapêutico , Troca Materno-Fetal/efeitos dos fármacos , Placenta/efeitos dos fármacos , Placenta/metabolismo , Circulação Placentária , Gravidez , Fator de Necrose Tumoral alfa/farmacocinética , Fator de Necrose Tumoral alfa/uso terapêutico , Adulto Jovem
13.
Health Soc Care Community ; 14(4): 329-40, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16787484

RESUMO

Migration has become a profound global phenomenon in this century. In Canada, uncoordinated policies, including those related to immigration, resettlement, employment, and government funding for health and social services, present barriers to immigrant women caregivers. The purpose of this paper is to share relevant insights from individual and group interviews with immigrant women family caregivers, service providers and policy influencers, and discuss these in relation to immigration, health and social policy, and programme trends in Canada. The present authors conducted individual interviews with immigrant women family caregivers (n = 29) in phase 1, followed by two group interviews with women family caregivers (n = 7), and two group interviews with service providers and policy-makers (n = 15) in phase 2. Using an inductive approach, the authors employed thematic content data analysis. Immigrant women experienced barriers to health and social services similar to Canadian-born family caregivers, particularly those who have low incomes, jobs with limited flexibility and heavy caregiving demands. These immigrant women family caregivers avoided certain formal services for a variety of reasons, including lack of cultural sensitivity. However, their challenges were compounded by language, immigration and separation from family in the home country. The identified barriers to support reinforce the importance of modifying and expanding policies and programmes affecting immigrant women's ability to care for family members with illnesses or disabilities within the context of Canadian society. Participants recommended changes to policies and programmes to deal with information, transportation, language, attitudinal and network barriers. The various barriers to services and programmes which were experienced by immigrant women caregivers underscore the importance of reviewing policies affecting immigration, caregiving, and access to health and social services. Intersectoral collaboration among agencies is essential to reduce the barriers identified in the present study, and to establish services which are linguistically and culturally appropriate.


Assuntos
Cuidadores , Emigração e Imigração , Acessibilidade aos Serviços de Saúde/organização & administração , Serviço Social/organização & administração , Mulheres , Povo Asiático , Canadá , Feminino , Política de Saúde , Humanos , Fatores Socioeconômicos
14.
Echo Res Pract ; 3(3): 85-93, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27628098

RESUMO

Herceptin (Trastuzumab) is a widely used and effective drug for the treatment of Her2+ breast cancer but its cardiotoxic side effects require regular monitoring by echocardiography. A 10% reduction in left ventricular ejection fraction can lead to suspension of treatment and therefore has significant implications for patient prognosis in terms of cardiac and cancer outcomes. Assessment of LV function by conventional 2D biplane method of discs (2DEF) has limitations in accuracy and reproducibility. Global longitudinal strain (GLS) is becoming more widely available and user friendly. It has been shown to demonstrate myocardial damage earlier in treatment than 2DEF, allowing the option of pharmacological intervention at a pre-clinical stage and preventing the interruption of Herceptin. This study compares the reproducibility of GLS with that of 2DEF in a routine clinical environment. Fifty echocardiograms performed on female patients undergoing Herceptin treatment were used to measure both 2DEF and GLS within the recommended standard appointment time of 40 min. The data were re-measured (blind) by the same operator a minimum of 14 days later to determine intra-operator variation. These data were also measured by a second operator (blind), to assess inter-operator variation. Analysis by direct comparison, intra-class correlation (ICC), coefficient of variation (CV) and Bland-Altman plots demonstrated that GLS is a more reproducible measurement than 2DEF. This is important to prevent clinical decisions being erroneously based on variation in operator measurement. The investigation also shows that with advances in machine software this is a practical addition to routine assessment rather than merely a research tool.

15.
Peptides ; 80: 32-39, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26752717

RESUMO

Increased understanding of the molecular components involved in mollusc reproduction may assist in understanding the evolutionary adaptations used by animals, including hermaphrodites, to produce offspring. The neuropeptide conopressin, a member of the vasopressin/oxytocin-like peptide family, can modulate various reproductive activities in invertebrates. In this study, we used the hermaphroditic land snail, Theba pisana, to investigate the presence and tissue-specific distribution of a conopressin gene. Our transcriptomic analysis of T. pisana CNS sheath tissue has revealed two conopressin gene transcripts (Tpi-conopressin-1 and Tpi-conopressin-2), each encoding for precursors containing an identical conopressin nonapeptide and a variable neurophysin. T. pisana conopressins share high identity with other land snails and slugs, as well as other mollusc and vertebrate vasopressin/oxytocin, supported by phylogenetic analysis. Conserved residues in the T. pisana neurophysin are important for peptide binding, and we present molecular dynamic models demonstrating the most likely stable structure of the Tpi-conopressin-1 peptide when associated with neurophysin. RT-PCR shows that Tpi-conopressin-1 is additionally expressed in reproductive tissues, including the dart sac, where abundant spatial expression throughout the sac region is found; this implies a role in 'love' dart synthesis or dart injection during mating. The presence of a conopressin receptor in the CNS sheath indicates CNS neural excitation. In summary, this study represents a detailed molecular analysis of conopressin in a land snail.


Assuntos
Peptídeos/genética , Peptídeos/metabolismo , Precursores de Proteínas/metabolismo , Caramujos/química , Animais , Expressão Gênica , Simulação de Dinâmica Molecular , Neurofisinas/química , Ocitocina/análogos & derivados , Ocitocina/química , Peptídeos/química , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores de Proteínas/química , Precursores de Proteínas/genética , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Homologia de Sequência de Aminoácidos , Caramujos/genética , Caramujos/metabolismo
16.
Biochim Biophys Acta ; 1399(2-3): 181-6, 1998 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-9765594

RESUMO

Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is expressed in a tissue-specific fashion with high levels in liver, heart, kidney, and muscle, and low levels in most other tissues. The ALDH2 promoter was found to bind nuclear proteins at a pair of adjacent sites approximately 300 bp upstream from the translation start site, each of which was contacted at motifs containing the hexamer A/GGGTCA. The 3' site was shown to bind in vitro translated HNF-4. It was also shown by electrophoretic mobility shift assay utilizing antibodies against nuclear factors and rat liver nuclear extracts to be bound by hepatocyte nuclear factor 4 (HNF-4), chicken ovalbumin upstream promoter transcription factor I and II, and retinoid X receptors. A reporter construct containing four copies of this promoter element was activated by co-transfection of an HNF-4 expression plasmid in COS-1 and hepatoma cell lines. These results suggest that the tissue specificity of ALDH2 expression is in part determined by its activation by HNF-4.


Assuntos
Aldeído Desidrogenase/genética , Proteínas de Ligação a DNA/genética , Fígado/metabolismo , Aldeído Desidrogenase/metabolismo , Aldeído-Desidrogenase Mitocondrial , Animais , Células COS , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Humanos , Fígado/enzimologia , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Musculares/enzimologia , Regiões Promotoras Genéticas , Transfecção , Células Tumorais Cultivadas
17.
J Mol Biol ; 290(4): 859-65, 1999 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-10398587

RESUMO

The enoyl-acyl carrier protein reductase (ENR) is involved in bacterial fatty acid biosynthesis and is the target of the antibacterial diazaborine compounds and the front-line antituberculosis drug isoniazid. Recent studies suggest that ENR is also the target for the broad-spectrum biocide triclosan. The 1.75 A crystal structure of EnvM, the ENR from Escherichia coli, in complex with triclosan and NADH reveals that triclosan binds specifically to EnvM. These data provide a molecular mechanism for the antibacterial activity of triclosan and substantiate the hypothesis that its activity results from inhibition of a specific cellular target rather than non-specific disruption of the bacterial cell membrane. This has important implications for the emergence of drug-resistant bacteria, since triclosan is an additive in many personal care products such as toothpastes, mouthwashes and soaps. Based on this structure, rational design of triclosan derivatives is possible which might be effective against recently identified triclosan-resistant bacterial strains.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/química , Oxirredutases/antagonistas & inibidores , Triclosan/farmacologia , Compostos de Boro/farmacologia , Cristalografia , Resistência Microbiana a Medicamentos , Enoil-(Proteína de Transporte de Acila) Redutase (NADH) , Escherichia coli/enzimologia , Proteínas de Escherichia coli , Ácido Graxo Sintase Tipo II , Modelos Moleculares , NAD/química , Oxirredutases/química , Triclosan/química
18.
Leukemia ; 9(9): 1499-507, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7658719

RESUMO

Experiments were performed to elucidate the mechanism through which p210 BCR-ABL, by its downstream signals, regulates c-myc messenger RNA expression in hematopoietic cells. We studied a model system in which stable expression of p210 BCR-ABL in interleukin-3 (IL-3) dependent murine myeloid cell lines led to growth factor independent transformation. Active c-myc transcription was observed in p210 BCR-ABL transformed cells by nuclear run-on assay, and in heterologous reporter assays performed with the 5' regulatory region of murine c-myc linked to firefly luciferase. Transcription initiation occurred primarily from the P2 promoter in p210 BCR-ABL transformed cells. Cis and trans elements responsible for transcription initiation from the c-myc P2 promoter were studied. Expression of E2F1 protein in p210 BCR-ABL transformed cells accounted, in part, for binding to the E2F site of the P2 c-myc promoter. The functional importance of E2F1 expression in p210 BCR-ABL transformed cells toward c-myc transcription was established in reporter assays performed with the P2 c-myc promoter containing either wild-type or mutant E2F sites. Mutation of the E2F motif of P2 5' c-myc reduced activity of the promoter by 50%. By gel mobility shift, E2F1 was found in P2 c-myc band shift complexes along with the cyclin-dependent kinase 2. Therefore, coupling of E2F to components of the retinoblastoma-cyclin pathway defines a route from p210 BCR-ABL to c-myc transcription, which is required for p210 BCR-ABL transformation.


Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Proteínas de Fusão bcr-abl , Genes myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Ligação Competitiva , Linhagem Celular Transformada , DNA/metabolismo , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Genes Reporter , Luciferases/metabolismo , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Proteína 1 de Ligação ao Retinoblastoma , Fator de Transcrição DP1
19.
Arch Dis Child Fetal Neonatal Ed ; 90(6): F523-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15863489

RESUMO

OBJECTIVE: To assess the accuracy of measurements of end tidal carbon dioxide (CO2) during neonatal transport compared with arterial and transcutaneous measurements. DESIGN: Paired end tidal and transcutaneous CO2 recordings were taken frequently during road transport of 21 ventilated neonates. The first paired CO2 values were compared with an arterial blood gas. The differences between arterial CO2 (Paco2), transcutaneous CO2 (TcPco2), and end tidal CO2 (Petco2) were analysed. The Bland-Altman method was used to assess bias and repeatability. RESULTS: Petco2 correlated strongly with Paco2 and TcPco2. However, Petco2 underestimated Paco2 at a clinically unacceptable level (mean (SD) 1.1 (0.70) kPa) and did not trend reliably over time within individual subjects. The Petco2 bias was independent of Paco2 and severity of lung disease. CONCLUSIONS: Petco2 had an unacceptable under-recording bias. TcPco2 should currently be considered the preferred method of non-invasive CO2 monitoring for neonatal transport.


Assuntos
Dióxido de Carbono/análise , Cuidado do Lactente/métodos , Transporte de Pacientes , Monitorização Transcutânea dos Gases Sanguíneos , Capnografia , Dióxido de Carbono/sangue , Humanos , Recém-Nascido , Monitorização Fisiológica/métodos , Pressão Parcial , Reprodutibilidade dos Testes , Respiração Artificial , Insuficiência Respiratória/sangue , Insuficiência Respiratória/metabolismo , Insuficiência Respiratória/terapia
20.
J Leukoc Biol ; 56(5): 636-43, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7964170

RESUMO

Antibody-facilitated macrophage (MP) destruction of Trypanosoma musculi involves ingestion and intracellular degradation of the parasites. It is likely, however, as we show here, that death of the trypanosomes is extracellular and it is the corpses that are ingested by MPs. We have utilized both peritoneal MPs and a cloned line (WLG 5) of mouse MPs to analyze the killing of T. musculi. Both types of MP were more effective when activated by interferon-gamma (IFN-gamma) rather than lipopolysaccharide (LPS). When activated by both, LPS diminished the killing activity stimulated by IFN-gamma, perhaps by changing the spectrum of lysins/toxins released by the MPs. Nitric oxide (NO) was found to be toxic for T. musculi and to be responsible, in part, for MP killing of the parasites. Although antibody and complement in concert caused lysis of T musculi, complement was not required for MP killing of the parasites. In the course of this investigation, we developed an in vitro system, involving line 5 MPs and plasma from infected mice containing resident parasites, that should prove satisfactory for detailed analyses of the mechanisms of the antibody-dependent, cell-mediated cure of T. musculi infection.


Assuntos
Ativação de Macrófagos/fisiologia , Macrófagos/fisiologia , Fagocitose/fisiologia , Trypanosoma/fisiologia , Animais , Citotoxicidade Celular Dependente de Anticorpos , Adesão Celular , Soros Imunes/imunologia , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Óxido Nítrico/biossíntese , Gravação de Videoteipe/métodos
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