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1.
Int J Oral Maxillofac Surg ; 50(4): 423-430, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32847711

RESUMO

The aim of this study was to analyse the rates of metastatic events and clinical outcomes of patients with adenoid cystic carcinoma (ACC) of the minor salivary glands and to critically evaluate the role of surgical therapy. A retrospective cohort study was designed including all patients with ACC of the oral minor salivary glands treated in the study department during the years 2010-2017. Relevant clinicopathological data were analysed to determine factors with an impact on overall survival (OS) and progression-free survival (PFS). Forty-one patients with primary ACC of the oral cavity and the oropharynx were included. Cervical metastases were found in 14 patients (34.1%) and were shown to have a significant negative impact on OS (P=0.009) and PFS (P=0.03). Sixteen patients developed disease recurrence during follow-up (39.0%) and most patients exhibited local disease recurrence with or without regional or distant metastases (14/16, 87.5%). Local recurrence was treated successfully with surgery in five cases. We recommend surgical therapy for patients with ACC of the minor salivary glands, including elective neck dissection and microvascular reconstruction, to optimize the planning of adjuvant therapy.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias das Glândulas Salivares , Carcinoma Adenoide Cístico/cirurgia , Humanos , Recidiva Local de Neoplasia , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/cirurgia , Glândulas Salivares Menores/cirurgia
2.
Cell Death Differ ; 22(7): 1219-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25571972

RESUMO

Tissue damage due to apoptotic or necrotic cell death typically initiates distinct cellular responses, leading either directly to tissue repair and regeneration or to immunological processes first, to clear the site, for example, of potentially damage-inducing agents. Mesenchymal stem cells (MSC) as well as immature dendritic cells (iDC) and monocytes migrate to injured tissues. MSC have regenerative capacity, whereas monocytes and iDC have a critical role in inflammation and induction of immune responses, including autoimmunity after tissue damage. Here, we investigated the influence of apoptotic and necrotic cell death on recruitment of MSC, monocytes and iDC, and identified hepatocyte growth factor (HGF) and the alarmin high mobility group box 1 (HMGB1) as key factors differentially regulating these migratory responses. MSC, but not monocytes or iDC, were attracted by apoptotic cardiomyocytic and neuronal cells, whereas necrosis induced migration of monocytes and iDC, but not of MSC. Only apoptotic cell death resulted in HGF production and HGF-mediated migration of MSC towards the apoptotic targets. In contrast, HMGB1 was predominantly released by the necrotic cells and mediated recruitment of monocytes and iDC via the receptor of advanced glycation end products. Moreover, necrotic cardiomyocytic and neuronal cells caused an HMGB1/toll-like receptor-4-dependent inhibition of MSC migration towards apoptosis or HGF, while recruitment of monocytes and iDC by necrosis or HMGB1 was not affected by apoptotic cells or HGF. Thus, the type of cell death differentially regulates recruitment of either MSC or monocytes and iDC through HGF and HMGB1, respectively, with a dominant, HMGB1-mediated role of necrosis in determining tropism after tissue injury.


Assuntos
Apoptose , Células Dendríticas/fisiologia , Proteína HMGB1/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Células-Tronco Mesenquimais/fisiologia , Monócitos/fisiologia , Necrose , Animais , Quimiotaxia , Humanos , Inflamação , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Regeneração
3.
J Intern Med ; 267(4): 418-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20433584

RESUMO

OBJECTIVES: Too vigorous exercise or activity increase frequently triggers postexertional malaise in people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a primary characteristic evident in up to 95% of people with ME/CFS. The present study aimed at examining whether two different types of exercise results in changes in health status, circulating elastase activity, interleukin (IL)-1beta and complement C4a levels. DESIGN: Comparative experimental design. SETTING: University. SUBJECTS: Twenty-two women with ME/CFS and 22 healthy sedentary controls INTERVENTIONS: participants were subjected to a submaximal exercise (day 8) and a self-paced, physiologically limited exercise (day 16). Each bout of exercise was preceded and followed by blood sampling, actigraphy and assessment of their health status. RESULTS: Both submaximal exercise and self-paced, physiologically limited exercise resulted in postexertional malaise in people with ME/CFS. However, neither exercise bout altered elastase activity, IL-1beta or complement C4a split product levels in people with ME/CFS or healthy sedentary control subjects (P > 0.05). Postexercise complement C4a level was identified as a clinically important biomarker for postexertional malaise in people with ME/CFS. CONCLUSIONS: Submaximal exercise as well as self-paced, physiologically limited exercise triggers postexertional malaise in people with ME/CFS, but neither types of exercise alter acute circulating levels of IL-1beta, complement C4a split product or elastase activity. Further studying of immune alterations in relation to postexertional malaise in people with ME/CFS using multiple measurement points postexercise is required.


Assuntos
Complemento C4a/metabolismo , Exercício Físico/fisiologia , Síndrome de Fadiga Crônica/metabolismo , Fadiga/metabolismo , Interleucina-1beta/sangue , Elastase Pancreática/sangue , Adulto , Estudos de Casos e Controles , Síndrome de Fadiga Crônica/fisiopatologia , Feminino , Humanos , Inquéritos e Questionários
4.
J Exp Biol ; 213(4): 572-84, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20118308

RESUMO

Mammals chew more rhythmically than lepidosaurs. The research presented here evaluated possible reasons for this difference in relation to differences between lepidosaurs and mammals in sensorimotor systems. Variance in the absolute and relative durations of the phases of the gape cycle was calculated from kinematic data from four species of primates and eight species of lepidosaurs. The primates exhibit less variance in the duration of the gape cycle than in the durations of the four phases making up the gape cycle. This suggests that increases in the durations of some gape cycle phases are accompanied by decreases in others. Similar effects are much less pronounced in the lepidosaurs. In addition, the primates show isometric changes in gape cycle phase durations, i.e. the relative durations of the phases of the gape cycle change little with increasing cycle time. In contrast, in the lepidosaurs variance in total gape cycle duration is associated with increases in the proportion of the cycle made up by the slow open phase. We hypothesize that in mammals the central nervous system includes a representation of the optimal chew cycle duration maintained using afferent feedback about the ongoing state of the chew cycle. The differences between lepidosaurs and primates do not lie in the nature of the sensory information collected and its feedback to the feeding system, but rather the processing of that information by the CNS and its use feed-forward for modulating jaw movements and gape cycle phase durations during chewing.


Assuntos
Primatas/fisiologia , Répteis/fisiologia , Animais , Fenômenos Biomecânicos , Lagartos/fisiologia , Mastigação
5.
Schizophr Res ; 98(1-3): 66-78, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17765477

RESUMO

BACKGROUND: Non-adherence with medication is a critical limitation in current long-term treatment of schizophrenia and a primary factor in poor quality-of-life outcomes. However, few treatments have addressed this shortcoming using an implantable drug delivery approach. The goal of this study was to provide in vitro and in vivo proof of concept for a long-term implantable risperidone delivery system in mice. METHODS: Implantable formulations of risperidone were created using the biodegradable polymer Poly Lactic co Glycolic Acid (PLGA) combined with various drug loads. Implant bioactivity was tested using in vitro release and stability studies, as well as in vivo pharmacokinetic and behavioral studies in mice. RESULTS: The pattern of risperidone release is influenced by various parameters, including polymer composition and drug load. In vitro measures demonstrate that risperidone is stable in implants under physiological conditions. Behavioral measures demonstrate the bioactivity of risperidone implants delivering 3 mg/kg/day in mice, while pharmacokinetic analyses indicate that reversibility is maintained throughout the delivery interval. CONCLUSIONS: The current report suggests that implantable formulations are a viable approach to providing long-term delivery of antipsychotic medications based on in vivo animal studies and pharmacokinetics. Implantable medications demonstrated here can last two months or longer while maintaining coherence and removability past full release, suggesting a potential paradigm shift in the long-term treatment of schizophrenia.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Implantes de Medicamento/farmacocinética , Modelos Animais , Risperidona/farmacocinética , Animais , Comportamento Animal/efeitos dos fármacos , Materiais Biocompatíveis , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/instrumentação , Desenho de Fármacos , Implantes de Medicamento/farmacologia , Potenciais Evocados Auditivos/efeitos dos fármacos , Potenciais Evocados Auditivos/fisiologia , Humanos , Técnicas In Vitro , Ácido Láctico , Camundongos , Camundongos Endogâmicos C57BL , Cooperação do Paciente , Poliésteres , Ácido Poliglicólico , Polímeros , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/fisiologia , Risperidona/farmacologia , Esquizofrenia/tratamento farmacológico
7.
Sex Dev ; 1(4): 255-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18391536

RESUMO

Modes of sex determination are quite variable in vertebrates. The developmental decision to form a testis or an ovary can be influenced by one gene, several genes, environmental variables, or a combination of these factors. Nevertheless, certain morphogenetic aspects of sex determination appear to be conserved in amniotes. Here we clone fragments of nine candidate sex-determining genes from the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination (TSD). We then analyze expression of these genes during the thermosensitive period of gonad development. In particular, we compare gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature. Expression of Dmrt1 and Sox9 mRNA increased gradually at the male-producing temperature, but was suppressed at the female-producing temperature. This finding suggests that Dmrt1 and Sox9 play a role in testis development. In contrast, expression of aromatase, androgen receptor (Ar), and Foxl2 mRNA was constant at the male-producing temperature, but increased several-fold in embryos at the female-producing temperature. Aromatase, Ar, and Foxl2 may therefore play a role in ovary development. In addition, there was a small temperature effect on ER alpha expression with lower mRNA levels found in embryos at the female-producing temperature. Finally, Dax1, Fgf9, and SF-1 were not differentially expressed during the sex-determining period, suggesting these genes are not involved in sex determination in the snapping turtle. Comparison of gene expression profiles among amniotes indicates that Dmrt1 and Sox9 are part of a core testis-determining pathway and that Ar, aromatase, ER alpha, and Foxl2 are part of a core ovary-determining pathway.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Diferenciação Sexual/genética , Temperatura , Tartarugas/genética , Animais , Sequência de Bases , Receptor alfa de Estrogênio/genética , Feminino , Gônadas/embriologia , Gônadas/metabolismo , Masculino , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Androgênicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Processos de Determinação Sexual , Fator Esteroidogênico 1/genética , Fatores de Transcrição/genética , Tartarugas/embriologia
8.
MMWR Suppl ; 54: 41-6, 2005 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-16177692

RESUMO

INTRODUCTION: Over-the-counter (OTC) medications are frequently used during the initial phase of illness, and increases in their sales might serve as an early indicator of communitywide disease outbreaks. Since August 2002, the New York City (NYC) Department of Health and Mental Hygiene (DOHMH) has tracked OTC medication sales to enhance detection of natural and intentional infectious disease outbreaks. OBJECTIVES: This report describes the surveillance system and presents results from retrospective analyses and a comparison between citywide trends in OTC medication sales and emergency department (ED) visits. METHODS: Sales data transmitted daily to DOHMH are categorized into two groups: influenza-like illness (ILI), which includes cough and influenza medications, and gastrointestinal illness (GI), which includes major brand and generic antidiarrheals. Cyclical, linear regression models were used to identify significant (p<0.05) increases in the daily ratio of ILI to analgesics sales (analgesics are used as a denominator in the absence of total sales). Daily and weekly average ratios of GI to analgesic sales were analyzed. Citywide trends in OTC ILI and GI medication sales were compared with ED visits for fever/influenza and diarrhea syndromes. RESULTS: Citywide ILI drug sales were highest during annual influenza epidemics and elevated during spring and fall allergy seasons, similar to trends in the ED fever/influenza syndrome. ILI sales did not consistently provide earlier warning than the ED system of communitywide influenza. GI drug sales increased during the fall and peaked during early winter and after the blackout of August 2003. Unlike ED diarrheal visits, GI medication sales did not substantially increase during late winter (February-March). CONCLUSION: Citywide OTC medication sales can provide indications of communitywide illness, including annual influenza epidemics. Antidiarrheal medication sales were more sensitive to increases in GI caused by norovirus and influenza than illness caused by rotavirus. OTC medication sales can be considered as an adjunct syndromic surveillance system but might not be as sensitive as ED systems.


Assuntos
Comércio/estatística & dados numéricos , Surtos de Doenças/prevenção & controle , Medicamentos sem Prescrição , Vigilância da População/métodos , Uso de Medicamentos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Humanos , Cidade de Nova Iorque/epidemiologia , Informática em Saúde Pública , Estudos Retrospectivos
9.
MMWR Suppl ; 53: 23-7, 2004 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-15714622

RESUMO

New York City's first syndromic surveillance systems were established in 1995 to detect outbreaks of waterborne illness. In 1998, daily monitoring of ambulance dispatch calls for influenza-like illness began. After the 2001 World Trade Center attacks, concern about biologic terrorism led to the development of surveillance systems to track chief complaints of patients reporting to emergency departments, over-the-counter and prescription pharmacy sales, and worker absenteeism. These systems have proved useful for detecting substantial citywide increases in common viral illnesses (e.g., influenza, norovirus, and rotavirus). However, the systems have not detected more contained outbreaks earlier than traditional surveillance. Future plans include monitoring school health and outpatient clinic visits, augmenting laboratory testing to confirm syndromic signals, and conducting evaluation studies to identify which of these systems will be continued for the long term.


Assuntos
Vigilância da População/métodos , Informática em Saúde Pública/tendências , Bioterrorismo/prevenção & controle , Doenças Transmissíveis Emergentes/prevenção & controle , Surtos de Doenças/prevenção & controle , Humanos , Cidade de Nova Iorque
10.
Nucleic Acids Res ; 29(16): 3327-34, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11504870

RESUMO

In addition to the cap-dependent mechanism, eukaryotic initiation of translation can occur by a cap-independent mechanism which directs ribosomes to defined start codons enabled by internal ribosome entry site (IRES) elements. IRES elements from poliovirus and encephalomyocarditis virus are often used to construct bi- or oligocistronic expression vectors to co-express various genes from one mRNA. We found that while cap-dependent translation initiation from bicistronic mRNAs remains comparable to monocistronic expression, internal initiation mediated by these viral IRESs is often very inefficient. Expression of bicistronic expression vectors containing the hepatitis B virus core antigen (HBcAg) together with various cytokines in the second cistron of bicistronic mRNAs gave rise to very low levels of the tested cytokines. On the other hand, the HBcAg was well expressed when positioned in the second cistron. This suggests that the arrangement of cistrons in a bicistronic setting is crucial for IRES-dependent translation of the second cistron. A systematic examination of expression of reporter cistrons from bicistronic mRNAs with respect to position was carried out. Using the dual luciferase assay system we show that the composition of reading frames on a bicistronic mRNA and the order in which they are arranged define the strength of IRES-dependent translation. Although the cellular environment and the nature of the IRES element influence translation strength the dominant determinant is the nature and the arrangement of cistrons on the mRNA.


Assuntos
Ordem dos Genes/genética , Genes/genética , Biossíntese de Proteínas/genética , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico/genética , Ribossomos/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Códon/genética , Citocinas/genética , Vírus da Encefalomiocardite/genética , Regulação da Expressão Gênica , Genes Reporter/genética , Vetores Genéticos/genética , Mutação/genética , Fases de Leitura Aberta/genética , Poliovirus/genética , Regiões Promotoras Genéticas/genética , RNA Mensageiro/metabolismo , Especificidade por Substrato , Transfecção , Proteínas do Core Viral/genética
11.
J Expo Anal Environ Epidemiol ; 10(5): 446-60, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11051535

RESUMO

Substantial evidence supports an association of particulate matter (PM) with cardiorespiratory illnesses, but little is known regarding characteristics of PM that might contribute to this association and the mechanisms of action. The Atlanta superstation sponsored by the Electric Power Research Institute as part of the Aerosol Research and Inhalation Epidemiology Study (ARIES) study is monitoring chemical composition of ambient particles by size fraction, as well as a comprehensive suite of other pollutants, at a site in downtown Atlanta during the 25-month period, August 1, 1998-August 31, 2000. Our investigative team is making use of this unique resource in several morbidity studies, called the "Study of Particulates and Health in Atlanta (SOPHIA)". The study includes the following components: (1) a time series investigation of emergency department (ED) visits for the period during which the superstation is operating; (2) a time series investigation of ED visits during the 5 years prior to implementation of the superstation; and (3) a study of arrhythmic events in patients equipped with automatic implantable cardioverter defibrillators (AICDs) for the period January 1, 1993-August 31, 2000. Thirty-three of 39 Atlanta area EDs are participating in the ED studies, comprising over a million annual ED visits. In this paper, we present initial analyses of data from 18 of the 33 participating EDs. The preliminary data set includes 1,662,713 ED visits during the pre-superstation time period and 559,480 visits during the superstation time period. Visits for four case groupings--asthma, chronic obstructive pulmonary disease (COPD), dysrhythmia, and all cardiovascular diseases (CVDs) combined--have been assessed relative to daily air quality indices, controlling for long-term temporal trends and meteorologic variables, using general linear models, generalized estimating equations and generalized additive models. Single-pollutant models predicting case visitation rates using moving averages of 0-, 1-, and 2-day lagged air quality variables were run. For the pre-superstation period, PM10 (24-h), ozone (8-h), SO2 (1-h), NO2 (1-h) and CO (1-h) were studied. For the first 12 months of superstation operation, the following air quality variables of a priori interest were available: ozone (8-h), NO2 (1-h), SO2 (1-h), CO (1-h), and 24-h measurements of PM10, coarse PM (PM 2.5-10 microm), PM2.5, polar VOCs, 10-100 nm particulate count and surface area, and in the PM2.5 fraction: sulfates, acidity, water-soluble metals, organic matter (OM), and elemental carbon (EC). During the pre-superstation time period, statistically significant, positive associations were observed for adult asthma with ozone, and for COPD with ozone, NO2 and PM10. During the superstation time period, the following statistically significant, positive associations were observed: dysrhythmia with CO, coarse PM, and PM2.5 EC; and all CVDs with CO, PM2.5 EC and PM2.5 OM. While covariation of many of the air quality indices limits the informativeness of this analysis, the study provides one of the first assessments of PM components in relation to ED visits.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Monitoramento Ambiental/métodos , Doenças Respiratórias/epidemiologia , Adulto , Poluentes Atmosféricos/análise , Doenças Cardiovasculares/etiologia , Coleta de Dados , Monitoramento Epidemiológico , Feminino , Georgia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial , Doenças Respiratórias/etiologia , Estatísticas não Paramétricas , População Urbana
12.
Fam Med ; 32(7): 456-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10916712

RESUMO

We describe here a feasible and data-based approach for obtaining important information about the percentage of our medical school graduates who primarily provide health care to the medically underserved. The logic and data used in our methodology have been acceptable to funding agencies. After making the initial investment in developing this approach, we can execute it at low cost to respond to relevant inquiries about the practice activities of our graduates. Other programs that can produce a computerized listing of post-residency graduates' practice locations can follow the procedure outlined above to demonstrate qualification for funding preferences.


Assuntos
Medicina de Família e Comunidade/educação , Área Carente de Assistência Médica , Área de Atuação Profissional/estatística & dados numéricos , Faculdades de Medicina/economia , Apoio ao Desenvolvimento de Recursos Humanos , Coleta de Dados/métodos , Sistemas de Gerenciamento de Base de Dados , Humanos , Michigan , Faculdades de Medicina/estatística & dados numéricos
13.
Am J Trop Med Hyg ; 62(6): 714-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11304061

RESUMO

In 1993 Sin Nombre virus was recognized as the cause of hantavirus pulmonary syndrome (HPS) and the deer mouse (Peromyscus maniculatus) was identified as the reservoir host. Surveillance by the Centers for Disease Control and Prevention and state health departments includes investigation to determine the likely site(s) and activities that led to infection, an environmental assessment of the home and workplace, and possibly rodent trappings at these sites. As of December 31, 1998, there were 200 confirmed cases from 30 states (43% case-fatality ratio). The national HPS case registry was examined to determine the incubation period of HPS. Review of 11 case-patients with well-defined and isolated exposure to rodents suggests that the incubation period of HPS is 9 to 33 days, with a median of 14-17 days. Case investigations allow a better understanding of the incubation time of HPS and may define high-risk behaviors that can be targeted for intervention.


Assuntos
Reservatórios de Doenças , Exposição Ambiental , Síndrome Pulmonar por Hantavirus/transmissão , Orthohantavírus , Peromyscus/virologia , Doenças dos Roedores/virologia , Adulto , Animais , Feminino , Infecções por Hantavirus/transmissão , Infecções por Hantavirus/veterinária , Infecções por Hantavirus/virologia , Síndrome Pulmonar por Hantavirus/virologia , Habitação , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Peromyscus/fisiologia , Recreação , Sistema de Registros , Fatores de Tempo
14.
Methods Mol Med ; 29: 313-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-21374331

RESUMO

DNA-based vaccination is a potent technique to prime cellular (T-cell mediated) immune responses (reviewed in 1). Many details of the priming of T-cell precursors by antigen translated from injected expression plasmid DNA are unknown. The relevant cell that is transfected in situ after DNA vaccination and that can process and present the protein in an immunogenic form has not yet been identified. Alternatively, the transfected cell may initiate 'cross-priming' in vivo by transferring processed antigen to a professional antigen-presenting cell (APC).

15.
Vaccine ; 16(4): 353-60, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9607055

RESUMO

Genes encoding the small (S) surface antigen (HBsAg) or the core (C) antigen (HBcAg) of hepatitis B virus (HBV) were cloned into the monocistronic expression vectors pCMV-1 or pCMV-2 under HCMV-IE promoter control. Coding fragments of these vectors were fused to generate a dicistronic expression construct pCMV/C-S in which the antigens HBcAg and HBsAg are coexpressed. Transient in vitro transfection studies demonstrated that HBcAg and HBsAg are coexpressed from this construct. Vaccination of mice of different H-2 haplotypes with mono- or dicistronic expression plasmids induced humoral and cellular immune responses to HBsAg and the HBcAg. In particular, intramuscular injection of 'naked' dicistronic plasmid DNA into mice elicited polyvalent humoral and cytotoxic T lymphocyte responses to HBsAg and HBcAg. The studies demonstrate that dicistronic expression plasmids are a novel way to construct a polyvalent vaccine against HBV that comprises HBsAg and HBcAg as immunogens.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Vacinas de DNA/administração & dosagem , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmídeos , Transfecção
16.
J Gen Virol ; 79 ( Pt 3): 587-90, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9519838

RESUMO

In small RNA viruses, arm-like segments located at the N or C termini have been suggested as mediators in the assembly of the capsid proteins. In many cases the arms of several subunits converge at a common point (the symmetry axis). Recent advances in studies of the hepatitis B virus (HBV) core protein attest the convergence of the segments preceding the protamine region, around the symmetry axis, where five or six HBc protein subunits converge. We report a mutation study of the region that we have suggested forms an arm-like structure, which reveals that a single mutation, Pro-138 --> Gly, prevents the full-length HBV core protein self-assembling into particles.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/química , Vírus da Hepatite B/química , Prolina/fisiologia , Proteínas do Core Viral/química , Sequência de Aminoácidos , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , Dados de Sequência Molecular , Mutagênese , Dobramento de Proteína , Estrutura Secundária de Proteína , Células Tumorais Cultivadas , Proteínas do Core Viral/genética , Proteínas do Core Viral/metabolismo
17.
Free Radic Biol Med ; 18(2): 185-94, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7744301

RESUMO

Lipoxygenase products were quantified in human mixed saliva and in saliva fractions obtained from a parotid or submandibular gland using gas chromatography-mass spectrometry and stable isotope dilution. In glandular saliva, only linoleic acid was detected at levels of 20-30 ng/ml. In contrast, mixed saliva showed a linoleic acid concentration of around 300 ng/ml, arachidonic acid levels of around 30 ng/ml, hydroxyoctadecadienoic acid (HODE) levels between 5 and 10 ng/ml, and hydroxyeicosatetraenoic acid (HETE) levels up to 25 ng/ml. By far the most abundant HETE was 12-HETE, and incubation experiments with arachidonic acid showed the presence of a substantial 12-lipoxygenase activity in human mixed saliva, but not in saliva fractions. This activity was identified as 12(S)-lipoxygenase activity by chiral analysis of the reaction product. Investigating mixed saliva and glandular saliva of patients with squamous cell carcinoma in the upper aerodigestive tract and of controls, most patients showed elevated levels of free arachidonic acid and elevated HETE levels. Besides a moderate increase in 12-HETE levels, markedly elevated concentrations of 5-HETE and 15-HETE were observed for the carcinoma patients. The level of free arachidonic acid and the quantitative HETE profile appear to be good markers for the inflammatory processes occurring in the oral mucosa and in saliva in response to the development of squamous cell carcinoma.


Assuntos
Ácidos Linoleicos Conjugados , Lipoxigenase/metabolismo , Neoplasias Bucais/enzimologia , Saliva/enzimologia , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico , Ácido Araquidônico/metabolismo , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Ácidos Linoleicos/metabolismo , Glândula Parótida/enzimologia , Glândula Submandibular/enzimologia
18.
Anal Biochem ; 224(1): 227-34, 1995 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7710076

RESUMO

An assay for the quantitative determination of the hydroxylation profile of long-chain fatty acids is described for gas chromatography negative-ion chemical ionization mass spectrometry and stable isotope dilution using [carboxyl-18O2]-labeled internal standards. The assay has been applied to the study of fatty acids isolated from body fluids, tissue, and cultured cells. Examples for the analyses of biological systems expressing 5-, 8-, 12-, or 15-lipoxygenase activity are given and the most important sources of analytical errors are addressed. Increased specificity compared to analysis by negative-ion chemical ionization, at the cost of sensitivity, can be achieved by the use of positive-ion electron impact ionization for the investigation of hydrogenated pentafluorobenzylester/trimethylsilylether derivatives. The method described provides complete, specific, and quantitative profiles of hydroxylated fatty acids originally present in biological samples or generated in vitro by incubation with polyunsaturated fatty acid substrates such as linoleic or arachidonic acid.


Assuntos
Ácidos Linoleicos Conjugados , Lipoxigenase/metabolismo , Animais , Linhagem Celular , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ácidos Hidroxieicosatetraenoicos/análise , Ácidos Linoleicos/análise , Camundongos
19.
Chemotherapy ; 38(6): 376-87, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1288961

RESUMO

BAY Y3118, 1-cyclopropyl-7-(2,8-diazabicyclo[4.3.0]non-8-yl)-6-fluoro-8- chloro-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid hydrochloride, is a new fluoroquinolone with antibacterial activity against an expanded spectrum of species including Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Enterococcus faecium, Streptococcus pneumoniae, Streptococcus pyogenes, and also anaerobes such as Bacteriodes fragilis and Clostridium perfringens. MIC90s for S. aureus, S. epidermidis, E. faecalis, and S. pneumoniae clinical isolates were 0.125, 0.25, 0.125 and 0.25 micrograms/ml, respectively. Against methicillin- and/or quinolone-resistant S. aureus, MIC50 levels of BAY Y3118 were 10- to 100-fold lower than those of tosufloxacin, sparfloxacin, or ciprofloxacin. The potency of BAY Y3118 against all members of the Enterobacteriaceae generally was equal to or 2-fold greater than that of ciprofloxacin or tosufloxacin. BAY Y3118 was also highly active against Haemophilus influenzae, Moraxella catarrhalis, Acinetobacter spp. and Pseudomonas aeruginosa. Increasing inoculum concentrations had a minimal effect on MIC determinations. The drug was determined to be bactericidal based upon reference MBCs and time-kill curves. From the results presented here, it was concluded that this new compound surpasses other known 4-quinolones both in spectrum and activity and that its further evaluation by in vitro, in vivo, and clinical studies seems warranted.


Assuntos
Anti-Infecciosos/farmacologia , Fluoroquinolonas , Bactérias Anaeróbias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Quinolonas/farmacologia , Resistência Microbiana a Medicamentos/genética , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mutação , Fatores de Tempo
20.
Can Vet J ; 31(10): 697-9, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17423677

RESUMO

The purpose of this study was to examine the litter size and stillbirth rate associated with cesarean-derived litters and to examine the relationship between the number of previous cesarean sections a sow had experienced and litter size. The records of 856 cesarean sections during a ten-year period from 1978 to 1988 were examined. The mean litter size was 10.6 +/- 3.2 and the mean number of stillborn pigs per litter was 0.2 +/- 0.8. The low level of stillbirth observed in this study provides supportive evidence to many earlier publications suggesting that the majority of stillborn pigs die during the birth process itself.A negative correlation between the number of previous cesarean sections a sow had experienced and litter size (r(2) = 0.015, p < 0.001) was observed. The slope of the regression line was -0.55, suggesting that litter size is reduced by approximately one-half a piglet for each cesarean section the sow has previously experienced. There are many factors which influence the variation in litter size. The small correlation coefficient (r(2) = 0.015) observed in this study indicates that only 1.5% of the variation in litter size can be explained by the number of previous cesarean sections that the sow has experienced.

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