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1.
Gynecol Oncol ; 159(1): 195-200, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32771277

RESUMO

OBJECTIVE: Determine the incidence and identify factors associated with potentially avoidable hospital readmissions due to uncontrolled symptoms or minor complications after surgery for gynecologic cancers. METHODS: Women who underwent major abdominal or pelvic surgery for a gynecologic malignancy between 2015 and 2017 were identified from the National Surgical Quality Improvement Program targeted hysterectomy dataset. Hospital readmissions within 30 days of surgery were categorized as indicated readmissions or potentially avoidable readmissions by three independent reviewers. Demographic, clinical, and operative covariates were evaluated to determine their association with type of readmission using bivariable tests and adjusted multinomial logistic regression models. RESULTS: A total of 20,986 women were identified. 19,814 (94.4%) were not readmitted, 894 (4.3%) were indicated readmissions, and 278 (1.3%) were potentially avoidable readmissions. Among those readmitted, 24% were potentially avoidable readmissions. Presence of ascites, increasing length of stay, and discharge to facility were associated with an increased risk of indicated and potentially avoidable readmissions. Age < 60 years old (RR 1.4, 95%CI 1.1-1.8), BMI ≥ 30 (RR 1.7, 95%CI 1.3-2.3), history of abdominal/pelvic surgery (RR 1.6, 95%CI 1.2-2.1), cervical cancer (RR 2.1, 95%CI 1.4-3.1), and open surgery (RR 2.1, 95%CI 1.4-3.2) were associated with an increased risk of a potentially avoidable readmission but not with increased risk of an indicated readmission. Median time to readmission did not differ between the two readmission groups (indicated = 8 days; avoidable = 7 days; p = .72). CONCLUSIONS: Among women with gynecologic cancer, 24% of all unplanned readmissions were attributed to uncontrolled symptoms or minor complications that were potentially avoidable. Age <60 years old, history of previous abdominal/pelvic surgery, obesity, cervical cancer, and open surgery were associated with an increase in risk of a potentially avoidable readmission.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Fatores Etários , Índice de Massa Corporal , Comorbidade , Conjuntos de Dados como Assunto , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Femininos/epidemiologia , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
2.
Gynecol Oncol ; 158(2): 331-338, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32553589

RESUMO

OBJECTIVES: Estimate the association between non-surgical management (NSM) (e.g. hormonal or radiation therapy) and overall survival among women with stage I endometrioid endometrial cancer (EEC) and identify patient and facility characteristics associated with receipt of NSM. METHODS: Women >45 years of age with clinical stage I EEC were identified in the National Cancer Database from 2004 to 2016. Women treated with NSM were compared with women treated initially with hysterectomy. Patient and facility characteristics associated with NSM were evaluated using logistic regression models. Association with overall survival was examined using log-rank tests, Kaplan-Meier curves, and Cox proportional hazards regression models with and without propensity score matching (PSM). RESULTS: A total of 112,469 women underwent treatment for stage I EEC between 2004 and 2016. 2776 (3%) received NSM, of whom 1987 (71%) received radiation therapy, 688 (25%) received hormonal therapy, and 101 (4%) received both. Older age, black race, higher Charlson-Deyo scores, Medicaid insurance, and low annual facility hysterectomy volume were associated with receiving NSM. The 5-year survival rate was 40% (95%CI: 37%-42%) for women with NSM compared to 89% (95%CI: 88%-89%) for hysterectomy. Women treated with NSM died at a faster rate than those who underwent primary hysterectomy (HR 7.6, 95%CI: 7.2-8.0; p < 0.001). This statistically significant difference in survival persisted in adjusted Cox proportional hazards models and after PSM. CONCLUSIONS: Women treated with NSM had a significantly higher risk of death compared to those undergoing hysterectomy for stage I EEC. Caution should be used when selecting patients for NSM given its worse outcomes.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Endometrioide/radioterapia , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/radioterapia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Endometrioide/mortalidade , Quimiorradioterapia , Estudos de Coortes , Bases de Dados Factuais , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Estados Unidos/epidemiologia
3.
J Org Chem ; 84(18): 11612-11622, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31433183

RESUMO

An operationally simple nickel-catalyzed hydroarylation reaction for alkynes is described. This three-component coupling reaction utilizes commercially available alkynes and aryl bromides, along with water and Zn. An air-stable and easily synthesized Ni(II) precatalyst is the only entity used in the reaction that is not commercially available. This reductive cross-coupling reaction displays a fairly unusual anti selectivity when aryl bromides with ortho substituents are used. In addition to optimization data and a preliminary substrate scope, complementary experiments including deuterium labeling studies are used to provide a tentative catalytic mechanism. We believe this report should inspire and inform other Ni-catalyzed carbofunctionalization reactions.


Assuntos
Alcinos/química , Hidrocarbonetos Aromáticos/síntese química , Hidrocarbonetos Bromados/química , Níquel/química , Água/química , Complexos de Coordenação/química , Hidrocarbonetos Aromáticos/química , Estrutura Molecular , Oxirredução , Estereoisomerismo
4.
Leukemia ; 31(2): 340-349, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27431016

RESUMO

The lymph node (LN) is the site of chronic lymphocytic leukemia (CLL) cell activation and proliferation. Aberrant microRNA (miRNA) expression has been shown to have a role in CLL pathogenesis; however, a comparison of miRNA expression between CLL cells in the LN and the peripheral blood (PB) has previously not been reported. On the basis of the analysis of 17 paired LN and PB samples from CLL patients, we identify a panel of miRNAs that are increased in LN CLL cells correlating with an activation phenotype. When evaluated in CLL cells from 38 patients pre and post treatment with ibrutinib, a subset of these miRNAs (miR-22, miR-34a, miR-146b and miR-181b) was significantly decreased in response to ibrutinib. A concomitant increase in putative miRNA target transcripts (ARID1B, ARID2, ATM, CYLD, FOXP1, HDAC1, IBTK, PTEN and SMAD4) was also observed. Functional studies confirmed targets of ibrutinib-responsive miRNAs to include messenger RNA transcripts of multiple tumor suppressors. Knockdown of endogenous miR-34a and miR146b resulted in increased transcription of tumor suppressors and inhibition of cell proliferation. These findings demonstrate that ibrutinib downregulates the expression of a subset of miRNAs related to B-cell activation leading to increased expression of miRNA targets including tumor suppressors and a reduction in cell proliferation.


Assuntos
Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor , Leucemia Linfocítica Crônica de Células B/genética , MicroRNAs/genética , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Adenina/análogos & derivados , Adulto , Idoso , Antígenos CD19/genética , Antígenos CD19/metabolismo , Linfócitos B/metabolismo , Linfócitos B/patologia , Biomarcadores/metabolismo , Proliferação de Células/efeitos dos fármacos , Análise por Conglomerados , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Piperidinas , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Interferência de RNA , RNA Mensageiro/genética
5.
Br J Cancer ; 113(3): 484-91, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26180921

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) lacks reliable serological biomarkers for predicting patients' survival and response to treatment. The present study examined the capability of serum LAMC2 and four known tumour markers for disease prognosis and patients' risk stratification. METHODS: LAMC2, CA 125, CEA, CYFRA 21-1 and SCC levels were retrospectively measured in sera obtained from 127 patients diagnosed with NSCLC by commercial immunoassays. Prognostic performance of the markers was compared with established clinical parameters and multivariate models were constructed to assess the prognostic complementarity of variables. RESULTS: LAMC2 showed significant prognostic ability for overall survival (hazards ratio: 1.607, 95% confidence interval: 1.268-2.037, P<0.0001) in the full cohort. LAMC2 and CYFRA 21-1 combination enhanced prognostic models based on common clinical parameters (c-index: 0.81 vs 0.72, P=0.00018), further enabling stratification of patients into clear risk groups. A bootstrap-based cross-validation analysis was supportive of our findings. Combination of LAMC2 and CA 125 showed similar performance. CONCLUSIONS: Our preliminary study proposes LAMC2 as a novel NSCLC prognostic factor. LAMC2 combined with CA 125 and CYFRA 21-1 could aid in clinical prediction of NSCLC patients' overall survival and inform clinical practice. Larger studies are necessary to unravel LAMC2's full potential as a new NSCLC biomarker.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Laminina/sangue , Neoplasias Pulmonares/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Antígeno Ca-125/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Queratina-19/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
7.
Am J Ind Med ; 49(9): 761-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16917830

RESUMO

BACKGROUND: It has been shown that exposure in intense exposure in swine barn facilities is associated with increased respiratory symptoms and reduction in pulmonary functions. This study investigated if systemic response could be predicted by FEV(1) response following swine barn exposure. METHODS: Naïve males were tested at baseline, low and high endotoxin and dust levels. Subjects were classified as "more responsive" (n = 9) or "less responsive" (n = 11) based on FEV(1) reduction following high endotoxin exposure. Health measures included pulmonary function testing, blood samples and nasal lavage. Environmental samples were collected from the barn. RESULTS: White blood cells and blood lymphocytes at low exposure were significantly greater in those who were "more responsive" compared to those who were "less responsive". There was a significant increase in blood lymphocytes, serum IL6, total nasal lavage cells and nasal IL8 at high exposure among "more responsive" subjects compared to "less responsive" subjects. CONCLUSIONS: Respiratory response to high-level endotoxin and dust exposure predicts evidence of inflammatory response throughout a range of endotoxin and dust exposures.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Poeira/análise , Endotoxinas/efeitos adversos , Abrigo para Animais , Hipersensibilidade/epidemiologia , Exposição Ocupacional/efeitos adversos , Doenças Respiratórias/epidemiologia , Suínos , Adolescente , Adulto , Poluentes Ocupacionais do Ar/análise , Criação de Animais Domésticos , Animais , Biomarcadores/análise , Estudos Cross-Over , Endotoxinas/análise , Humanos , Hipersensibilidade/imunologia , Interleucina-6/análise , Interleucina-8/análise , Masculino , Exposição Ocupacional/análise , Testes de Função Respiratória , Doenças Respiratórias/imunologia , Estatísticas não Paramétricas
8.
Chest ; 118(3): 852-60, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10988215

RESUMO

STUDY OBJECTIVES: A study was conducted to evaluate the acute health effects of wearing an N-95 disposable respirator in a swine confinement facility. DESIGN: A crossover trial design was used in the study. SETTING: The study was carried out at the research facilities of the Centre for Agricultural Medicine, the Royal University Hospital, and the Prairie Swine Centre Inc, Saskatoon, Saskatchewan, Canada. PARTICIPANTS: Twenty-one nonsmoking healthy male subjects with no previous swine barn exposure participated in the study. INTERVENTIONS: The subjects participated in a laboratory session (baseline day), a 4-h exposure in a traditional swine room wearing the respirator (intervention day), and a 4-hour exposure in a traditional swine room without a respirator (nonintervention day). MEASUREMENTS: Lung function, methacholine challenge tests, blood counts, nasal lavage, and cytokines in serum and nasal lavage fluid. RESULTS: Mean (+/- SE) shift change in FEV(1), from preexposure to postexposure, was highest on nonintervention day (-8.1+/-1.01%) and was significantly different from intervention day (0.32+/-0.62%; p<0.0001) and baseline day (1.57+/-0.51%; p<0.0001). Similar patterns were observed in the mean values of the provocative concentration of a substance (methacholine) causing a 20% fall in FEV(1) (nonintervention day, 130.4+/-36.9 mg/mL; intervention day, 242.0+/-38.0 mg/mL; and baseline day, 328.0 mg/mL +/-34.1 mg/mL). Significant increases in serum neutrophil levels and nasal cell counts were observed on the nonintervention day in comparison to the baseline and intervention days. Significant increases also were found in the levels of cytokines interleukin (IL)-6 and IL-8 in nasal lavage fluid and in the levels of IL-6 in serum for the nonintervention day in comparison to the other 2 days. CONCLUSIONS: The results demonstrate that an N-95 disposable respirator can help to significantly reduce acute negative health effects in subjects not previously exposed to a swine barn environment.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Hiper-Reatividade Brônquica/prevenção & controle , Equipamentos Descartáveis , Doenças Profissionais/prevenção & controle , Dispositivos de Proteção Respiratória , Adolescente , Adulto , Animais , Hiper-Reatividade Brônquica/etiologia , Hiper-Reatividade Brônquica/metabolismo , Hiper-Reatividade Brônquica/fisiopatologia , Testes de Provocação Brônquica/métodos , Estudos Cross-Over , Equipamentos Descartáveis/normas , Humanos , Interleucina-6/sangue , Interleucina-8/metabolismo , Contagem de Leucócitos , Masculino , Cloreto de Metacolina , Líquido da Lavagem Nasal/química , Líquido da Lavagem Nasal/citologia , Doenças Profissionais/etiologia , Doenças Profissionais/metabolismo , Doenças Profissionais/fisiopatologia , Controle de Qualidade , Testes de Função Respiratória , Dispositivos de Proteção Respiratória/normas , Inquéritos e Questionários
10.
J Appl Toxicol ; 20(1): 69-80, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10641018

RESUMO

Eight phthalate esters, with alcohol chain lengths of 1-11 carbon atoms and with various degrees of branching, were tested in vitro in the L5178Y mouse lymphoma mammalian cell mutation assay and in the Balb/3T3 cell transformation assay. The tests were performed as part of a voluntary testing agreement between the Chemical Manufacturers Association's Phthalate Esters Panel and the United States Environmental Protection Agency (US EPA). The esters tested were: dimethyl phthalate (DMP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), di-¿n-hexyl, n-octyl, n-decyl¿ phthalate (610P), di-isononyl phthalate (DINP), di-¿heptyl, nonyl, undecyl¿ phthalate (711P), di-isodecyl phthalate (DIDP) and di-undecyl phthalate (DUP). Both DMP and DBP were found to produce significant increases in the mutant frequency in the mouse lymphoma assay in the presence but not in the absence of an Aroclor-induced rat liver activation system (S-9). Ester 610P gave equivocal results in the mouse lymphoma assay in the presence and absence of rat liver S-9. There was no indication of mutagenic potential for any of the other test materials in the mouse lymphoma assay, and none of the test materials increased transformation frequency in the Balb/3T3 cell transformation assay. Aldehyde metabolites of the de-esterified alcohols are postulated to play a role in the positive results for DMP and DBP.


Assuntos
Testes de Carcinogenicidade , Testes de Mutagenicidade , Ácidos Ftálicos/toxicidade , Células 3T3 , Animais , Transformação Celular Neoplásica , Ésteres , Leucemia L5178 , Camundongos , Camundongos Endogâmicos BALB C , Ácidos Ftálicos/metabolismo , Ratos , Células Tumorais Cultivadas
11.
Food Chem Toxicol ; 37(9-10): 931-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10541447

RESUMO

Plant-derived polyphenolics and other chemicals with antioxidant properties have been reported to inhibit the expression of genotoxic activity by pro-oxidant chemicals (Sai et al., 1992, 1994; Teel and Castonguay, 1992). In vitro and in vivo studies with ionizing radiation suggest that hydroquinone (HQ) may have similar protective effects (Babaev et al., 1994). The present study was conducted to determine whether HQ is capable of inhibiting the induction of micronuclei in the bone marrow of mice following exposure to an oxidant, potassium bromate or KBrO3 (Nakajima et al., 1989; Sai et al., 1992, 1994). To be able to interpret the results of this work, it was also necessary to determine whether HQ is itself genotoxic when fed in the diet. HQ diets (0.8%) fed to mice for 6 days reduced the background incidence of micronuclei compared with the basal diet. KBrO3 dosed ip (12.5-100 mg/kg) produced a dose-dependent increase in micronuclei as reported by others. Mice fed 0.8% HQ diets 6 days, and then dosed intraperitoneally with KBrO3, showed a 36% reduction in micronuclei across the range of KBrO3 dose levels. This effect was associated with a reduction in the background micronucleus response as well as a reduction in response to KBrO3. Statistical significance (P < or = 0.05), observed at a dose of 25 mg/kg KBrO3 in the mice fed the control diet, was abolished in the group fed 0.8% HQ. When mice were given 50 mg HQ/kg by oral gavage and then given 50 mg KBrO3/kg ip 20 min later, the micronucleus response induced by KBrO3, was lower in animals given HQ. The results of this study demonstrate that large doses of HQ may be given orally without induction of micronuclei or bone marrow depression, that HQ reduces the background micronucleus response in animals fed a basal diet, and that the HQ reduces the micronucleus response to KBrO3 as well as background incidence of micronuclei in KBrO3-dosed animals. The protective effect of HQ may be due to enzyme induction or a direct antioxidant effect of HQ against oxidants commonly present in the diet.


Assuntos
Antimutagênicos/farmacologia , Bromatos/toxicidade , Hidroquinonas/farmacologia , Mutagênicos/toxicidade , Administração Oral , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/ultraestrutura , Bromatos/administração & dosagem , Dieta , Interações Medicamentosas , Feminino , Hidroquinonas/administração & dosagem , Hidroquinonas/sangue , Injeções Intraperitoneais , Masculino , Camundongos , Testes para Micronúcleos
12.
Mutat Res ; 442(2): 133-47, 1999 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-10393282

RESUMO

It has been reported that 14C-labeled methyl-n-amyl ketone (MAK, 2-heptanone) is able to bind spontaneously, in vitro, to isolated rat liver DNA to the extent of 400 pmol/mg DNA; and that 14C-MAK, when given by gavage to female Fischer 344 rats, resulted in HPLC chromatograms of isolated, hydrolyzed liver DNA in which some radiolabel was not associated with the four normal DNA bases dA, dT, dC, and dG. The present studies were undertaken to re-examine the hypothesis that MAK is able to bind to rat liver DNA. In the in vitro study, liver nuclear DNA was incubated with [2-14C]-labeled MAK (25 mCi/mmol) in the absence, or in the presence of rat liver microsomes, precipitated, washed free of unbound MAK, and counted by scintillation spectrometry. No binding to DNA by MAK was detectable. In the in vivo study, groups of five female F344 rats were exposed by inhalation to 0, 80, 400, or 1000 ppm MAK for 6 h/day for 10 days. DNA was purified from the liver nuclei of the 0 and 1000 ppm dosed animals, and 32P-postlabeling techniques were used to assay for adducts. No DNA adducts were detected using these techniques. It was concluded that MAK lacks the ability to bind to rat liver DNA in vitro and in vivo.


Assuntos
Adutos de DNA/metabolismo , Cetonas/metabolismo , Fígado/metabolismo , Animais , Autorradiografia , Cromatografia em Camada Fina , DNA/isolamento & purificação , Feminino , Fígado/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Radioisótopos de Fósforo , Ratos , Ratos Endogâmicos F344
13.
Mediators Inflamm ; 8(1): 37-41, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10704088

RESUMO

On the basis that ozone (O3) can upregulate cellular antioxidant enzymes, a morphological, biochemical and functional renal study was performed in rats undergoing a prolonged treatment with O3 before renal ischaemia. Rats were divided into four groups: (1) control, a medial abdominal incision was performed to expose the kidneys; (2) ischaemia, in animals undergoing a bilateral renal ischaemia (30 min), with subsequent reperfusion (3 h); (3) O3 + ischaemia, as group 2, but with previous treatment with O3 (0.5 mg/kg per day given in 2.5 ml O2) via rectal administration for 15 treatments; (4) O2 + ischaemia, as group 3, but using oxygen (O2) alone. Biochemical parameters as fructosamine level, phospholipase A, and superoxide dismutases (SOD) activities, as well as renal plasma flow (RPF) and glomerular filtration rate (GFR), were measured by means of plasma clearance of p-amino-hippurate and inulin, respectively. In comparison with groups 1 and 3, the RPF and GFR were significantly decreased in groups 2 and 4. Interestingly, renal homogenates of the latter groups yielded significantly higher values of phospholipase A activity and fructosamine level in comparison with either the control (1) and the O3 (3) treated groups. Moreover renal SOD activity showed a significant increase in group 3 without significant differences among groups 1, 2 and 4. Morphological alterations of the kidney were present in 100%, 88% and 30% of the animals in groups 2, 4 and 3, respectively. It is proposed that the O3 protective effect can be ascribed to the substantial possibility of upregulating the antioxidant defence system capable of counteracting the damaging effect of ischaemia. These findings suggest that, whenever possible, ozone preconditioning may represent a prophylactic approach for minimizing renal damage before transplantation.


Assuntos
Isquemia , Rim/irrigação sanguínea , Ozônio/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Animais , Tolerância a Medicamentos , Frutosamina/metabolismo , Inulina/farmacocinética , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Fosfolipases A/metabolismo , Ratos , Ratos Wistar , Reperfusão , Superóxido Dismutase/metabolismo , Temperatura , Ácido p-Aminoipúrico/farmacocinética
15.
Mol Cell Biol ; 18(5): 2502-13, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9566871

RESUMO

Ty1 retrotransposons in Saccharomyces cerevisiae are maintained in a state of transpositional dormancy. We isolated a mutation, rtt100-1, that increases the transposition of genomic Ty1 elements 18- to 56-fold but has little effect on the transposition of related Ty2 elements. rtt100-1 was shown to be a null allele of the FUS3 gene, which encodes a haploid-specific mitogen-activated protein kinase. In fus3 mutants, the levels of Ty1 RNA, protein synthesis, and proteolytic processing were not altered relative to those in FUS3 strains but steady-state levels of TyA, integrase, and reverse transcriptase proteins and Ty1 cDNA were all increased. These findings suggest that Fus3 suppresses Ty1 transposition by destabilizing viruslike particle-associated proteins. The Fus3 kinase is activated through the mating-pheromone response pathway by phosphorylation at basal levels in naive cells and at enhanced levels in pheromone-treated cells. We demonstrate that suppression of Ty1 transposition in naive cells requires basal levels of Fus3 activation. Substitution of conserved amino acids required for activation of Fus3 derepressed Ty1 transposition. Moreover, epistasis analyses revealed that components of the pheromone response pathway that act upstream of Fus3, including Ste4, Ste5, Ste7, and Ste11, are required for the posttranslational suppression of Ty1 transposition by Fus3. The regulation of Ty1 transposition by Fus3 provides a haploid-specific mechanism through which environmental signals can modulate the levels of retrotransposition.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Quinases Ativadas por Mitógeno , Recombinação Genética , Retroelementos/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , DNA Complementar/metabolismo , DNA Fúngico/metabolismo , Proteínas Fúngicas/genética , Haploidia , Integrases/metabolismo , Fator de Acasalamento , Mutação , Peptídeos , Feromônios , Processamento de Proteína Pós-Traducional , RNA Fúngico/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , Transdução de Sinais
16.
Can Respir J ; 5(6): 472-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10070175

RESUMO

OBJECTIVE: To determine predictors of longitudinal changes in pulmonary function in swine confinement workers. DESIGN: Longitudinal study conducted from November 1989 to June 1991 and January 1994 to May 1995. SETTING: Swine confinement workers in Saskatchewan. PARTICIPANTS: Forty-two swine confinement workers who were studied in 1989/90 and studied again in 1994/95. RESULTS: Of 98 male swine confinement workers (mean age SD 36.3 11.1 years) studied at baseline, 42 were studied again five years following. Complete information on baseline across-shift pulmonary function (preshift forced expiratory volume in 1 s [FEV1], forced vital capacity [FVC], and every 2 h FEV1 and FVC during the shift), and five-year follow-up pulmonary function (with FEV1 and FVC) were available on all 42 subjects. Mean across-shift changes (preshift measurement to last measurement of the day) at baseline were -159. 8 61.7 mL in FEV1 and -35.3 65.6 mL in FVC. Mean annual rate change between baseline and follow-up for FEV1 was -53.9 61.7 mL/year and for FVC -48.9 71.6 mL/year. After adjusting for age, height, smoking and hours spent in the barn, the baseline across-shift change in FEV1 and FVC was a significant predictor of annual rate change in FEV1 (P=0.01) and FVC (P=0.02), respectively. To determine the effects of indoor air quality on longitudinal lung function decline, indoor air environmental measurements were analysed. Complete information on respiratory health and indoor air quality was available on 34 of the 42 subjects. Assessment of indoor environment of swine barns included a summer and winter measurement for airborne dust, gases and endotoxin levels. After adjusting for age, height, smoking, ammonia and hours spent in the barn, the endotoxin level (Eu/mg)was a significant predictor of annual rate change for FEV1 but not FVC. CONCLUSIONS: These results suggest that shift change is an important predictor of longitudinal changes in lung function in swine confinement workers and that endotoxin exposures may mediate annual decline in FEV1 in these workers.


Assuntos
Criação de Animais Domésticos , Pulmão/fisiologia , Saúde Ocupacional , Suínos , Adolescente , Adulto , Fatores Etários , Poluentes Ocupacionais do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Amônia/análise , Animais , Estatura , Dióxido de Carbono/análise , Poeira/análise , Endotoxinas/análise , Seguimentos , Volume Expiratório Forçado/fisiologia , Previsões , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Saskatchewan , Fumar/fisiopatologia , Capacidade Vital/fisiologia
17.
Am J Respir Crit Care Med ; 156(2 Pt 1): 410-7, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9279217

RESUMO

A crossover trial was conducted to evaluate the acute human health effects of a dust control technology in a swine confinement facility. Twenty lifetime nonsmoking male subjects, with no evidence of allergy or asthma and no previous swine barn exposure, participated in the study, which included a laboratory session (baseline), 5-h exposure in a swine room sprinkled with canola oil (treatment) and 5-h exposure in a traditional swine room (control). Mean values of inhalable dust concentrations and endotoxin levels in the control room were significantly greater than those observed in the treatment room. Mean shift changes in FEV1 from preexposure to end of exposure were 1.1% (standard error, 0.63%) on baseline day, -1.9% (0.63%) on treatment day, and -9.9% (1.12%) on control day; the differences in the shift changes were statistically significant. Mean value of methacholine concentration that reduced the FEV1 by 20% (PC20) in bronchoprovocation tests on baseline day was significantly different from that on treatment day (p = 0.04) and that on control day (p < 0.001). Significant increases were also observed in white blood cell counts and nasal lavage cell counts on the control day in comparison with the other two days. Blood neutrophil counts after control room exposure were twice those observed on baseline and after exposure to the treatment room. Significant differences were also observed in IL-1 beta, IL-6, and IL-8 nasal lavage cytokines and in IL-6 serum cytokine. These results suggest that the canola oil dust control method is effective in improving indoor air quality in swine barns and reducing acute health effects in naive healthy subjects.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Criação de Animais Domésticos , Poeira/prevenção & controle , Ácidos Graxos Monoinsaturados/administração & dosagem , Abrigo para Animais , Adolescente , Adulto , Doenças dos Trabalhadores Agrícolas/etiologia , Doenças dos Trabalhadores Agrícolas/fisiopatologia , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Animais , Estudos Cross-Over , Poeira/efeitos adversos , Humanos , Masculino , Óleo de Brassica napus , Testes de Função Respiratória/métodos , Testes de Função Respiratória/estatística & dados numéricos , Saskatchewan , Inquéritos e Questionários , Suínos , Fatores de Tempo
18.
Chest ; 111(6): 1733-41, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9187201

RESUMO

We conducted a longitudinal study to determine the annual rate decline in pulmonary function measurements in male swine confinement workers. For comparison, a grain farming group and a nonfarming rural-dwelling control group were also chosen for the longitudinal study. Two hundred seventeen swine confinement workers, 218 grain farmers, and 179 nonfarming control subjects had valid pulmonary function measurements at the baseline observation conducted in 1990 to 1991 and at the second observation conducted in 1994 to 1995. The swine confinement workers were younger (mean age=38.3+/-11.7 [SD] years) than the nonfarming control subjects (42.6+/-10.4 years) and the grain farmers (44.5+/-11.9 years). When stratified by age, nonfarming control subjects had the lowest mean annual rate decline in FEV1 and FVC in all age categories. The swine confinement workers had the largest annual rate decline in FEV1 and FVC, and this was most obvious in the middle age categories. After controlling for age, height, smoking, and baseline pulmonary function, swine confinement workers had excess annual decline of 26.1 mL in FEV1 (p=0.0005), 33.5 mL in FVC (p=0.0002), and 42.0 mL/s in forced expiratory flow between 25% and 75% of FVC (FEF[25-75%]) (p=0.02) over nonfarming control subjects. Grain farmers had excess annual decline of 16.4 mL in FEV1 (p=0.03), 26.7 mL in FVC (p=0.002), and 11.2 mL/s in FEF(25-75%) (p=0.38) over control subjects. These findings suggest that workers engaged in the swine industry and grain farmers appear prone to accelerated yearly losses in lung function and may therefore be at risk for the future development of chronic airflow limitation.


Assuntos
Criação de Animais Domésticos , Pulmão/fisiologia , Adulto , Envelhecimento/fisiologia , Agricultura , Animais , Grão Comestível , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória/estatística & dados numéricos , População Rural , Saskatchewan , Fumar/fisiopatologia , Suínos
19.
J Invest Surg ; 9(6): 415-22, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8981214

RESUMO

Hypercholesterolemia induces venous vasomotor dysfunction. This study examines the endothelial and smooth muscle cell vasoreactivity of external jugular veins from rabbits fed either a normal or a 1% cholesterol diet for 8 weeks with and without L-arginine supplementation (2 g/kg day-1 orally for the last 5 weeks). Isometric tension studies were performed on harvested jugular veins. Concentrations of serum cholesterol were 20-fold higher than controls and serum L-arginine twofold higher than untreated animals. Hypercholesterolemia induced hypersensitivity to norepinephrine (p < .05), bradykinin (p < .05), and histamine (p < .05) with a contractile response to serotonin compared to controls. L-Arginine supplementation decreased bradykinin hypersensitivity but had no effect on the changes in norepinephrine serotonin and histamine responses compared to controls. Hypercholesterolemia interfered with relaxation induced by acetylcholine but with L-arginine, normal acetylcholine-induced, endothelium-dependent relaxation returned (54 +/- 10%, compared to 40 +/- 14% in control veins; p > .05). Non-endothelium-dependent relaxation to sodium nitroprusside of precontracted veins was unaffected by the presence of high cholesterol concentrations. This study suggests that L-arginine therapy may ameliorate hypercholesterolemia-induced functional abnormalities in endothelial cells.


Assuntos
Arginina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Hipercolesterolemia/fisiopatologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Arteriosclerose/induzido quimicamente , Arteriosclerose/tratamento farmacológico , Arteriosclerose/fisiopatologia , Bradicinina/farmacologia , Dieta , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Histamina/farmacologia , Hipercolesterolemia/induzido quimicamente , Veias Jugulares/patologia , Veias Jugulares/fisiopatologia , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/citologia , Nitroprussiato/farmacologia , Norepinefrina/farmacologia , Cloreto de Potássio/farmacologia , Coelhos , Serotonina/farmacologia , Vasodilatadores/farmacologia
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