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1.
Occup Med (Lond) ; 74(2): 146-151, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38369319

RESUMO

BACKGROUND: Evidence synthesis in the field of occupational safety and health (OSH) has been continuously growing over the last two decades. With over 100 systematic reviews now published, the Cochrane Work Review group has played an important role in this development and the Cochrane Thematic Group 'Work & Health & Social Security' was established recently to combine evidence from both the OSH and insurance medicine fields. Worldwide, many organizations produce and synthesize evidence in OSH that can complement and support each other. We believe that a global network including Cochrane and others can collaborate on methods development and in the production, synthesis, use and dissemination of different types of evidence even more effectively. AIMS: To determine if establishing a global network for evidence synthesis in OSH is feasible. METHODS: We conducted a survey of international and national institutions between November 2022 and January 2023 using LimeSurvey. Participants included representatives of affiliated and sustaining members of the International Commission on Occupational Health, national institutes for OSH, academia and other international organizations. RESULTS: From 151 invitations, we received responses from 57 representatives of 54 organizations. Representatives reported that their organization will contribute financially on an annual basis (n = 1) or provide in-kind support (n = 10), and will probably be able to provide financial or in-kind support (n = 25). CONCLUSIONS: The feasibility criterion was met and an international network is being established.


Assuntos
Saúde Ocupacional , Humanos , Estudos de Viabilidade , Inquéritos e Questionários
3.
Endosc Ultrasound ; 3(Suppl 1): S15-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26425516

RESUMO

INTRODUCTION: The objective of this case series study by retrospective analysis was to determine the relevance of endoscopic ultrasound (EUS) in therapeutic decision esophageal cancer. MATERIAL AND METHODS: Using medical records of the Department of Endoscopy of Santa Casa de São Paulo, we have collected data from 16 patients, in 4 years, diagnosed of esophageal cancer, and presented in the form of clinical cases to a specialist surgeon in esophageal cancer and a clinical oncologist, for therapeutic evaluation before and after the outcome of EUS. RESULTS: Both of them choose non-resective and not curative methods (68.8% by surgeon vs. 87.5% oncologist) before EUS. The best treatment by the surgeon was chemotherapy and palliative radiotherapy associated (25%) and palliative endoscopic prostheses (25%), and by the oncologist, neoadjuvant chemotherapy and radiotherapy associated (56.2%). After EUS, the resective surgical treatment was the both choice in only 6.2% of cases, and the rest of 93.8%, non-resective. The surgeon choice was chemotherapy and palliative radiotherapy associated (44%), and oncologist choice was neoadjuvant chemotherapy and radiotherapy associated (44%). Analysis by the Chi-square method, comparing respective versus non-resective treatment, surgeon versus oncologist, with and without the EUS, obtained values of P = 0.39 and P = 0.46, respectively. The comparison between healing and non-healing treatment had the same P value. Regarding the change in behavior (resective vs. non-resective), there was a change of approach by the surgeon in 25% of cases (P = 0.17) and the oncologist moved conduct in 6.25% of cases. Comparing the changing of behavior among experts, the P value was 0.33. Despite evidence of behavior change after the EUS, the statistical point of view, the P value had no significant relevance. The main factor involved is probably due to a reduced number of sample cases. However, this is a pilot study, and is needed other with a larger number of cases. CONCLUSION: The data obtained allow us to conclude that EUS proved to be an important test for the change in staging and therapeutic management of esophageal cancer.

4.
Clin Ter ; 161(5): 461-4, 2010.
Artigo em Italiano | MEDLINE | ID: mdl-20949245

RESUMO

Chronic fatigue syndrome (CFS) is a clinical syndrome characterized by profound disabling chronic fatigue associated with a wide array of other physical symptoms. Its etiology is currently unknown. Among the various hypotheses, considerable interest has been placed in the hypothalamus-pituitary-adrenal axis as a possible target of the pathogenesis of CFS. This article reviews the available scientific evidence about a role of hypothalamic-pituitary-adrenal axis in the pathogenesis of chronic fatigue syndrome.


Assuntos
Síndrome de Fadiga Crônica/etiologia , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia
5.
G Ital Med Lav Ergon ; 32(4 Suppl): 92-4, 2010.
Artigo em Italiano | MEDLINE | ID: mdl-21438227

RESUMO

A study leaded in 2005 by the ILO on diet habits in different countries pointed out that poor diet at the workplace (leading to malnutrition or overweight and obesity) costs up to 20% & in lost productivity. Obesity is a major cause for absenteeism and can modify physiologic and immune responses to neurotoxins and chemical agents. Obese subjects show a higher risk to develop cardiovascular diseases, musculoskeletal disorders, due to exposure to vibrations, etc; quite often these workers are discriminated, are more sensitive to work-related stress and might experience a reduced self-esteem. Obesity can cause relevant working handicaps linked to reduction of agility, to early fatigue and to difficulties in identifying and use of suitable PPE. As a consequence, obese workers show a higher rate of work accidents and may receive some restrictions in the fitness assessment carried out by the occupational health physician during periodical examinations.


Assuntos
Dieta , Promoção da Saúde , Obesidade/prevenção & controle , Saúde Ocupacional , Humanos
6.
Acta Otolaryngol ; 128(8): 915-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18607955

RESUMO

CONCLUSIONS: The absence of recurrences after final nasal reconstruction demonstrates the reliability of our three-stage strategy and the necessity to delay nasal reconstruction, focusing attention on oncological safety for nasal non-melanoma skin cancer (NMSC) with mucosal invasion. OBJECTIVES: To validate a therapeutic strategy aimed at oncological safety and minimization of possible recurrences after full-thickness excision of nasal NMSC with mucosal invasion. The strategy was divided into three stages: surgical excision with clinically safe perilesional skin margins and extemporary frozen section histological control; 8-15 months follow-up leaving the nasal defect unreconstructed with a 'wait and see' strategy; new extemporary histological control of defect margins and, if negative, definitive reconstruction. PATIENTS AND METHODS: Twenty patients affected by nasal NMSC with mucosal invasion were treated and followed up. RESULTS: Basal cell carcinoma was the most common lesion (75%), followed by squamous cell carcinoma (25%). Ultrasonography excluded lymphatic involvement for SCC. Before final reconstruction, extemporary histological examination revealed the presence of tumour cells in three patients. After tumour extirpation, these patients were resubmitted to a new follow-up period before reconstruction. No recurrences were observed after definitive nasal reconstruction in all patients during the 5-year follow-up.


Assuntos
Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Nasais/cirurgia , Rinoplastia/métodos , Neoplasias Cutâneas/cirurgia , Idoso , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal , Invasividade Neoplásica , Neoplasias Nasais/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Resultado do Tratamento
7.
Dis Esophagus ; 21(5): 461-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18430188

RESUMO

Chagas' disease (CD) is highly prevalent in South America. Brazilian surgeons and gastroenterologists gained valuable experience in the treatment of CD esophagopathy (chagasic achalasia) due to the high number of cases treated. The authors reviewed the lessons learned with the treatment of achalasia by different centers experienced in the treatment of Chagas' disease. Preoperative evaluation, endoscopic treatment (forceful dilatation and botulinum toxin injection), Heller's myotomy, esophagectomy, conservative techniques other than myotomy, and reoperations are discussed in the light of personal experiences and review of International and Brazilian literature. Aspects not frequently adopted by North American and European surgeons are emphasized. The review shows that nonadvanced achalasia is frequently treated by Heller's myotomy. Endoscopic treatment is reserved to limited cases. Treatment for end-stage achalasia is not unanimous. Esophagectomy was a popular treatment in advanced disease; however, the morbidity/mortality associated to the procedure made some authors seek different alternatives, such as Heller's myotomy and cardioplasties. Minimally invasive approach to esophageal resection may change this concept, although few centers perform the procedure routinely.


Assuntos
Doença de Chagas/cirurgia , Acalasia Esofágica/cirurgia , Esôfago/patologia , Brasil , Cateterismo/métodos , Doença de Chagas/mortalidade , Doença de Chagas/terapia , Acalasia Esofágica/mortalidade , Acalasia Esofágica/terapia , Esofagectomia/métodos , Esofagoplastia/métodos , Esofagoscopia/métodos , Esôfago/cirurgia , Feminino , Humanos , Injeções Intralesionais , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fármacos Neuromusculares/uso terapêutico , Prognóstico , Medição de Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Resultado do Tratamento
8.
Aust Dent J ; 53(1): 26-33, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18304238

RESUMO

BACKGROUND: General dental care can effectively control disease and restore damaged tissue, yet little is known about its impact on patients' subjective oral health, namely treatment goals and oral health-related quality of life (OHRQoL). This study aimed to evaluate change in both aspects of subjective oral health among elderly adults receiving publicly-funded, general dental care. METHODS: We conducted a prospective, single-group intervention study of adults aged 75+ years receiving care through the South Australian Dental Service (SADS). Before receiving dental care, subjects completed the Oral Health Impact Profile (OHIP-14) questionnaire which evaluates OHRQoL. In this questionnaire, subjects rated the extent to which they had attained a self-nominated oral health goal. Dentists provided standard-of-care treatment and six months later the OHIP-14 and goal attainment questions were re-administered. RESULTS: Among the 253 adults studied, overall improvements in OHRQoL were observed (p < 0.05), although the effect was dependent on pre-treatment goal: mean OHIP-14 scores did not change significantly for subjects whose goal was less pain/discomfort while significant improvements were observed for subjects with other treatment goals. In contrast, mean goal attainment ratings improved significantly (P < 0.05), regardless of treatment goal categories. CONCLUSIONS: Dental care was associated with improvements in subjective oral health, although different patterns of improvement were observed for OHRQoL compared with goal attainment ratings.


Assuntos
Assistência Odontológica para Idosos , Objetivos , Saúde Bucal , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Assistência Odontológica Integral/classificação , Assistência Odontológica para Idosos/classificação , Dentaduras , Dor Facial/prevenção & controle , Feminino , Seguimentos , Nível de Saúde , Humanos , Arcada Parcialmente Edêntula/classificação , Masculino , Mastigação/fisiologia , Estudos Prospectivos
9.
G Ital Med Lav Ergon ; 29(3 Suppl): 492-4, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18409793

RESUMO

The authors present the section, part of the ISPESL's website, dedicated to tobacco smoke at work. In this subdivision many topics regarding problems caused by tobacco smoke in the workplaces are gathered and discussed so that different personnel responsible for health and prevention at work can find a technical answer to take part to the improvement of the psychophysical welfare of both smokers and non smokers. The general information section has collected the relative Italian and international laws regarding smoking in the workplace along with representative court cases, and some publications and essays which have been presented on this topic. Inside the section dedicated to the employers and companies, the authors have posted useful importation on smoking in the workplace which includes some tools that can turn to be interesting to those who are supposed to be involved with prevention, the updated addresses of the national public antismoking centers, experiences and activities against tobacco smoke of national and international companies, events regarding smoke at work, informative sheets and leaflets for smokers, link to other site that argue about this topic. Moreover, there is a section dedicated to a forum where Internet user can share their experiences and thoughts on workplaces free from tobacco smoke.


Assuntos
Internet , Saúde Ocupacional , Prevenção do Hábito de Fumar , Poluição por Fumaça de Tabaco/prevenção & controle , Local de Trabalho , Humanos
10.
Acta Chir Plast ; 48(4): 123-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17294911

RESUMO

Discovered in 1830, paraffin oil, a purified hydrocarbon from petroleum, has been used in the past as an augmentation material in various parts of the human body, for restoration body defects or aesthetic body contouring. We illustrated the case of an 18-year-old guy who self-injected some paraffin oil (Baby Johnson's Oil) in his lips, cheek and chin, with aesthetical purpose. We showed the classical course and proper management of paraffinoma's lesions. The need for complete excision of all involved tissue to treat the condition successfully is illustrated, and a clinical, pathological and histological discussion is presented. To our knowledge paraffinoma of the face caused by a self-injection of mineral oil has been never reported in literature.


Assuntos
Técnicas Cosméticas/efeitos adversos , Óleos/administração & dosagem , Parafina/administração & dosagem , Adolescente , Humanos , Injeções Subcutâneas , Masculino
11.
J Biol Chem ; 276(47): 43541-7, 2001 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-11557765

RESUMO

Recently, we and others have reported that mRNAs may be polyadenylated in plant mitochondria, and that polyadenylation accelerates the degradation rate of mRNAs. To further characterize the molecular mechanisms involved in plant mitochondrial mRNA degradation, we have analyzed the polyadenylation and degradation processes of potato atp9 mRNAs. The overall majority of polyadenylation sites of potato atp9 mRNAs is located at or in the vicinity of their mature 3'-extremities. We show that a 3'- to 5'-exoribonuclease activity is responsible for the preferential degradation of polyadenylated mRNAs as compared with non-polyadenylated mRNAs, and that 20-30 adenosine residues constitute the optimal poly(A) tail size for inducing degradation of RNA substrates in vitro. The addition of as few as seven non-adenosine nucleotides 3' to the poly(A) tail is sufficient to almost completely inhibit the in vitro degradation of the RNA substrate. Interestingly, the exoribonuclease activity proceeds unimpeded by stable secondary structures present in RNA substrates. From these results, we propose that in plant mitochondria, poly(A) tails added at the 3' ends of mRNAs promote an efficient 3'- to 5'- degradation process.


Assuntos
Exodesoxirribonucleases/metabolismo , Mitocôndrias/genética , Conformação de Ácido Nucleico , RNA Mensageiro/metabolismo , Solanum tuberosum/enzimologia , Sequência de Bases , DNA Complementar , Exodesoxirribonuclease V , Hidrólise , Cinética , Dados de Sequência Molecular , RNA Mensageiro/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico
12.
AIDS Res Hum Retroviruses ; 17(4): 337-48, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11242520

RESUMO

The surface envelope glycoprotein gp46 of the human T cell leukemia virus type 1 elicits a strong immune response. Its protective role against HTLV-1 infection in animal models is well established, suggesting that recombinant envelope glycoproteins or synthetic peptides could be used as an effective vaccine. However, reports have indicated that some variations in envelope sequences may induce incomplete cross-neutralization between HTLV-1 strains. To identify amino acid changes that might be involved in induction of specific neutralizing antibodies, we studied sera from three patients (2085, 2555, and 2709) infected by HTLV-1 with surface glycoprotein gp46 harboring variations in amino acid sequence at positions 39, 72, 265, and 290. Inhibition of syncytia induced by parental, chimeric, or point-mutated envelope proteins indicated that sera 2555 and 2709 primarily recognized neutralizable epitopes located in N- and C-terminal parts of the gp46 glycoprotein. Amino acids changes at positions 39, 265, and 290 greatly impaired recognition of neutralizing epitopes recognized by these two sera. These results demonstrate that amino acid changes in envelope glycoprotein gp46 can induce strain-specific neutralizing antibodies in some patients. On the other hand, the neutralizing activity of serum 2085 was not affected by amino acid changes at positions 39, 265, and 290, suggesting that the neutralizing antibodies present in this serum were directed against epitopes located in other parts of the molecule, possibly those located in the central domain of the molecule, which has the same amino acid sequence in the three viruses.


Assuntos
Produtos do Gene env/química , Produtos do Gene env/imunologia , Variação Genética/genética , Anticorpos Anti-HTLV-I/sangue , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Proteínas Oncogênicas de Retroviridae/química , Proteínas Oncogênicas de Retroviridae/imunologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Produtos do Gene env/genética , Células Gigantes/fisiologia , Anticorpos Anti-HTLV-I/imunologia , Antígenos HTLV-I/imunologia , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/virologia , Humanos , Dados de Sequência Molecular , Mutação , Testes de Neutralização , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Oncogênicas de Retroviridae/genética , Transfecção
13.
Virus Genes ; 23(3): 257-61, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11778693

RESUMO

An anomalous high frequency of ATL was observed in a remote 'noir maroons' village of French Guiana. Since it is not clear if HTLV-I is responsible for different frequencies of disease in different geographical areas, we undertook a comparison of the population with a similar one located in Gabon. We found a much higher degree of gp46 surface envelope glycoprotein sequence conservation in the Guianese village than in the Gabonese one.


Assuntos
Variação Genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Leucemia-Linfoma de Células T do Adulto/virologia , Sequência de Bases , Sequência Conservada , DNA Viral , Feminino , Guiana Francesa/epidemiologia , Gabão/epidemiologia , Produtos do Gene env/genética , Humanos , Leucemia-Linfoma de Células T do Adulto/epidemiologia , Masculino , Dados de Sequência Molecular , Filogenia , Proteínas Oncogênicas de Retroviridae/genética , Alinhamento de Sequência
14.
Rev Assoc Med Bras (1992) ; 46(2): 98-105, 2000.
Artigo em Português | MEDLINE | ID: mdl-11022349

RESUMO

UNLABELLED: Treatment of chemical agent ingestion remain controversial. The incidence of these episodes has increased over the several last decades due to a variety reasons. PURPOSE: To analyze the occurrence, complications and results of the treatment of chemically induced esophagogastric injury. METHODS: Twenty-one adult patients with chemically induced esophagogastric injury were retrospectively studied. The patients were admitted up to 23 days after ingestion of a chemical agent to the Emergency Department of Santa Casa of Sao Paulo University Hospital from August, in a 12-year period. The mean age was 32.1 years. Eleven patients were of the female gender, which attempted suicide. Soda was the most ingested agent (76.2%), muriatic acid was present in three cases (14.3%) followed by one case of sulfur acid and another one of ammonia (4.8% each). RESULTS: Injuries of the Larynx and Pharynx were frequently associated with those of the esophagus, accounting for 18 cases (85.7%). Esophageal, gastric and duodenal injuries were assessed and classified according to endoscopic features. Five cases each of severe esophageal or gastric lesions were present. CONCLUSION: Treatment and outcome varied and suggested placement of esophageal tube to be harmful. Global mortality rate was 28.6% with the highest rate related to esophageal injuries of the third degree.


Assuntos
Queimaduras Químicas/diagnóstico , Cáusticos/efeitos adversos , Doenças do Esôfago/induzido quimicamente , Gastropatias/induzido quimicamente , Ácidos Sulfúricos/efeitos adversos , Adolescente , Queimaduras Químicas/mortalidade , Queimaduras Químicas/terapia , Doenças do Esôfago/mortalidade , Doenças do Esôfago/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Hidróxido de Sódio/efeitos adversos , Gastropatias/mortalidade , Gastropatias/terapia , Tentativa de Suicídio
15.
Rev. Assoc. Med. Bras. (1992) ; 46(2): 98-105, abr.-jun. 2000. tab
Artigo em Português | LILACS | ID: lil-268360

RESUMO

O tratamento da ingestão de agentes químicos corrosivos continua controverso. A incidência desses episódios tem aumentado nas últimas décadas por várias razões. OBJETIVO: Analisar a ocorrência, as complicações e os resultados do tratamento da lesão esôfago - gástrica causada por agentes químicos. MÉTODOS: Foram estudados retrospectivamente 21 pacientes adultos com lesão esôfago-gástrica, causada por ingestão de substância química, admitidos até 23 dias após o episódio, no Serviço de Emergência da Santa Casa de Misericórdia de São Paulo num período de 12 anos. A média de idade foi 32,1 anos e 11 doentes pertenciam ao sexo feminino, as quais mais freqüentemente tinham intenções suicidas. A soda cáustica foi o produto mais ingerido (76,2 por cento), ingestão de ácido muriático ocorreu em três casos (14,3 por cento), amoníaco e ácido sulfúrico em um caso (4,8 por cento) cada. RESULTADOS: As lesões faríngeas e laríngeas estiveram freqüentemente associadas às lesões de esôfago, presentes em 18 casos (85,7 por cento). As lesões esofágicas, gástricas e duodenais foram avaliadas e classificadas por endoscopia. Lesões graves esofágicas ou gástricas estiveram presentes em cinco casos cada. CONCLUSÃO: O tratamento e os resultados foram variados, mas sugeriram que a sondagem esofágica foi prejudicial. A mortalidade global foi 28,6 por cento, mais elevada na lesão esofágica grau 3.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Pessoa de Meia-Idade , Queimaduras Químicas/diagnóstico , Cáusticos/efeitos adversos , Doenças do Esôfago/induzido quimicamente , Gastropatias/induzido quimicamente , Ácidos Sulfúricos/efeitos adversos , Queimaduras Químicas/mortalidade , Queimaduras Químicas/terapia , Doenças do Esôfago/mortalidade , Doenças do Esôfago/terapia , Estudos Retrospectivos , Hidróxido de Sódio/efeitos adversos , Gastropatias/mortalidade , Gastropatias/terapia , Tentativa de Suicídio
16.
J Chromatogr B Biomed Sci Appl ; 737(1-2): 85-95, 2000 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-10681045

RESUMO

The carboxyl half of the surface envelope protein of HTLV-I contains the major immunodominant and neutralizable domains. Using two affinity chromatography steps and a combination of high salt concentration and non-ionic detergent, we purified this part of the envelope protein from Escherichia coli. Analysis of some immmunological and biological properties of this protein indicated that it was folded in a way that preserved the correct structure of this domain of the HTLV-I envelope protein. It could be utilized in structural studies to further understand the mechanisms of HTLV-I entry and to better define the component(s) of an effective vaccine.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/química , Proteínas do Envelope Viral/química , Bactérias/genética , Cromatografia de Afinidade/métodos , Eletroforese em Gel de Poliacrilamida , Vetores Genéticos , Células Gigantes/citologia , Anticorpos Anti-HTLV-I/sangue , Humanos , Dobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/isolamento & purificação
17.
FEBS Lett ; 458(3): 337-42, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10570936

RESUMO

The proteins involved in mitochondrial mRNA processing and degradation in higher plants have yet to be identified. As a first step towards this aim, we report here the characterisation of a nuclear-encoded DExH box RNA helicase (AtSUV3) localised in Arabidopsis thaliana mitochondria. The AtSUV3 mRNA is assembled from the 16 exons of a weakly expressed unique gene and the predicted protein has a calculated molecular weight of 63.6 kDa. Subcellular fractionation of transgenic plants expressing AtSUV3/GUS fusion proteins localises this protein in mitochondria. The N-terminal domain of AtSUV3 containing the motifs characteristic of DExH box RNA helicases exhibits a low endogenous ATPase activity in vitro which can be stimulated by the presence of mitochondrial RNA, confirming that AtSUV3 is an RNA helicase.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/enzimologia , Proteínas de Plantas/genética , RNA Helicases/genética , RNA/metabolismo , Adenosina Trifosfatases/metabolismo , Sequência de Aminoácidos , RNA Helicases DEAD-box , Regulação da Expressão Gênica de Plantas , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Proteínas de Plantas/química , Plantas Geneticamente Modificadas , Pseudogenes , RNA Helicases/química , RNA Mensageiro/metabolismo , RNA Mitocondrial , Proteínas Recombinantes de Fusão , Homologia de Sequência de Aminoácidos , Solanum tuberosum/genética
18.
J Virol ; 73(11): 9369-76, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10516045

RESUMO

The nucleotide sequence of human T-cell leukemia virus type 1 (HTLV-1) is highly conserved, most strains sharing at least 95% sequence identity. This sequence conservation is also found in the viral env gene, which codes for the two envelope glycoproteins that play a major role in the induction of a protective immune response against the virus. However, recent reports have indicated that some variations in env sequences may induce incomplete cross-reactivity between HTLV-1 strains. To identify the amino acid changes that might be involved in the antigenicity of neutralizable epitopes, we constructed expression vectors coding for the envelope glycoproteins of two HTLV-1 isolates (2060 and 2072) which induced human antibodies with different neutralization patterns. The amino acid sequences of the envelope glycoproteins differed at four positions. Vectors coding for chimeric or point-mutated envelope proteins were derived from 2060 and 2072 HTLV-1 env genes. Syncytium formation induced by the wild-type or mutated envelope proteins was inhibited by human sera with different neutralizing specificities. We thus identified two amino acid changes, I173-->V and A187-->T, that play an important role in the antigenicity of neutralizable epitopes located in this region of the surface envelope glycoprotein.


Assuntos
Anticorpos Antivirais/imunologia , Glicoproteínas/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Sequência de Aminoácidos , Anticorpos Antivirais/sangue , Linhagem Celular , Efeito Citopatogênico Viral , Genes env/genética , Células Gigantes/fisiologia , Glicoproteínas/química , Glicoproteínas/genética , Vírus Linfotrópico T Tipo 1 Humano/química , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Testes de Neutralização , Mutação Puntual , Proteínas Recombinantes de Fusão/imunologia , Transfecção , Proteínas do Envelope Viral/genética
19.
EMBO J ; 18(13): 3757-66, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10393190

RESUMO

In sunflower, PET1-cytoplasmic male sterility is correlated with the presence of a novel mitochondrial gene (orf522) located 3' to the atpA gene. The dicistronic atpA-orf522 transcripts are preferentially destabilized in male florets of 'restored to fertility' plants as compared with sterile plants. In this report, we show that atpA-orf522 transcripts may be polyadenylated in vivo at their 3' termini and that a tissue-specific increase in the level of polyadenylated atpA-orf522 transcripts correlates with the tissue-specific instability of atpA-orf522 mRNAs in male florets of the restored hybrid plants. In addition, we have identified two distinct ribonuclease activities in sunflower mitochondria, one of which preferentially degrades polyadenylated as compared with non-polyadenylated RNA substrates corresponding to the 3' UTR of atpA-orf522 transcripts. These in vivo and in vitro results show that polyadenylation is involved in the degradation pathway of the mitochondrial atpA-orf522 transcripts and that polyadenylation can be developmentally regulated by a nuclear gene(s) upon restoration of fertility.


Assuntos
Citoplasma/genética , Helianthus/genética , Helianthus/fisiologia , Mitocôndrias/genética , Poli A/metabolismo , RNA Mensageiro/metabolismo , Regiões 3' não Traduzidas/genética , Sequência de Bases , Núcleo Celular/genética , Quimera/genética , Fertilidade , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Helianthus/citologia , Cinética , Mitocôndrias/enzimologia , Fases de Leitura Aberta/genética , Especificidade de Órgãos , Estruturas Vegetais/genética , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Ribonucleases/isolamento & purificação , Ribonucleases/metabolismo , Solanum tuberosum/enzimologia , Especificidade por Substrato
20.
AIDS Res Hum Retroviruses ; 15(10): 909-20, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10408728

RESUMO

By the use of sera of human T cell leukemia virus type I (HTVL-I)-infected individuals it was shown that amino acid substitutions at positions 192 (proline to serine) and 250 (serine to proline) in major immunodominant regions (175-199 and 239-261) of the surface envelope glycoprotein (gp46) of the virus may influence the humoral response. Since human sera are polyclonal in nature, one cannot readily discriminate between an immunoglobulin-specific recognition and multiple bindings of diverse antibodies. To overcome this difficulty we generated murine monoclonal antibodies to synthetic peptides mimicking all or portions of these gp46 regions. The reactivity of some of these antibodies to synthetic peptides harboring (or not harboring) the preceding amino acid substitutions at position 192 or 250, to denatured gp46 by Western blotting, and to live (variously substituted) HTLV-I-infected cells, combined with blocking experiments with various peptides, allow us to conclude that the major epitopes (positions 183-191, 190-197, 190-199, and 246-252) in the two immunodominant regions may elicit different antibody responses according to their sequences. It is worth noting that in a reporter gene inhibition assay, it was found that a neutralizing monoclonal antibody (MF1), the epitope for which is located between residues 190 and 197, had a high level of activity when cells (2060) harboring a gp46 with proline at position 192 were used and had no activity toward cells (1010) with a serine at this position. Therefore our results establish that certain amino acid substitutions of gp46 may drastically affect the antigenicity of the molecule and the biological activity of the antibodies elicited.


Assuntos
Anticorpos Antideltaretrovirus/imunologia , Antígenos de Deltaretrovirus/imunologia , Epitopos de Linfócito B/imunologia , Produtos do Gene env/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Epitopos Imunodominantes/imunologia , Peptídeos/imunologia , Proteínas Oncogênicas de Retroviridae/imunologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Anticorpos Antideltaretrovirus/biossíntese , Antígenos de Deltaretrovirus/química , Mapeamento de Epitopos , Técnica Indireta de Fluorescência para Anticorpo , Produtos do Gene env/síntese química , Humanos , Immunoblotting , Epitopos Imunodominantes/química , Isotipos de Imunoglobulinas/imunologia , Fígado/citologia , Fígado/imunologia , Camundongos , Dados de Sequência Molecular , Peptídeos/síntese química , Proteínas Oncogênicas de Retroviridae/síntese química , Células Vero
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