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1.
Artigo em Inglês | MEDLINE | ID: mdl-34492509

RESUMO

Analytical methods used for quality control of plants and plant extracts are based on the identification and quantification of chemical markers to manage batch reproducibility and efficacy. The aim of this work was to assess the performance of a High Performance Thin Layer Chromatography (HPTLC) method developed for quality control of industrial dry extracts of ribwort plantain (P. lanceolata L.), using 2,2-diphenyl 1-picrylhydrazyle (DPPH) effect directed chemical reaction for antioxidant activity of acteoside, a phenylethanoid glycoside commonly used as a marker for P. lanceolata L., and to demonstrate the applicability of the Life Cycle Management of Analytical Methods concept to quantitative HPTLC-DPPH methods. The first step was the determination of the Analytical Target Profile (ATP) and Target Measurement Uncertainty (TMU), taking into account the quality control requirements for such extracts and the detection method applicable range. Once the desired range was established, an evaluation of the calibration function was conducted using several calibration models. Due to the lack of reference samples, spiked samples were used to evaluate the accuracy of the method by means of Total Analytical Error (TAE) determination, using prediction intervals calculation for the selected calibration functions. Measurement Uncertainty (MU) was also estimated, allowing the final choice of the calibration function to be used for quality control, giving the most fit for purpose performance level in accordance with the product specifications. As Life Cycle Management of the method also includes its routine use, the Measurement Uncertainty was checked on spiked and unspiked extract samples with different dilution levels, in order to verify the accordance of results between spiked and unspiked samples and to prepare a replication strategy to be applied during the routine use of the method.


Assuntos
Compostos de Bifenilo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Glucosídeos , Fenóis , Picratos/metabolismo , Plantago/química , Compostos de Bifenilo/química , Glucosídeos/análise , Glucosídeos/química , Glucosídeos/metabolismo , Limite de Detecção , Modelos Lineares , Fenóis/análise , Fenóis/química , Fenóis/metabolismo , Picratos/química , Extratos Vegetais/química , Reprodutibilidade dos Testes
2.
R Soc Open Sci ; 7(4): 191429, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32431861

RESUMO

There is a paucity of information on the foraging ecology, especially individual use of sea-ice features and icebergs, over the non-breeding season in many seabird species. Using geolocators and stable isotopes, we defined the movements, distribution and diet of adult Antarctic petrels Thalassoica antarctica from the largest known breeding colony, the inland Svarthamaren, Antarctica. More specifically, we examined how sea-ice concentration and free-drifting icebergs affect the distribution of Antarctic petrels. After breeding, birds moved north to the marginal ice zone (MIZ) in the Weddell sector of the Southern Ocean, following its northward extension during freeze-up in April, and they wintered there in April-August. There, the birds stayed predominantly out of the water (60-80% of the time) suggesting they use icebergs as platforms to stand on and/or to rest. Feather δ15N values encompassed one full trophic level, indicating that birds fed on various proportions of crustaceans and fish/squid, most likely Antarctic krill Euphausia superba and the myctophid fish Electrona antarctica and/or the squid Psychroteuthis glacialis. Birds showed strong affinity for the open waters of the northern boundary of the MIZ, an important iceberg transit area, which offers roosting opportunities and rich prey fields. The strong association of Antarctic petrels with sea-ice cycle and icebergs suggests the species can serve, year-round, as a sentinel of environmental changes for this remote region.

3.
Acta Cient Venez ; 51(1): 45-52, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-10974707

RESUMO

The resistance to cytotoxic drugs represents a major obstacle to successful cancer therapy. The intrinsic resistance of tumoral cells is one of major causes of treatment failure. The overexpression of a membrane associated glycoprotein, P-glycoprotein, in tumoral cell lines, resistant to a wide range of drugs, permitted the description of a multidrug resistance (MDR) phenotype. This P-glycoprotein, which appears to play a role in drug efflux is encoded by the mdr1 gene in humans. The frequent mdr1 gene overexpression in clinically resistant tumours suggest that this gene may be the cause of treatment failure in human cancer. This review summarizes recent developments in this area, which suggest that both the activity of the pump and its genetic regulation are potential targets for new anticancer therapies.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Neoplasias/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Membrana Celular/metabolismo , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , Genes MDR/genética , Humanos , Fenótipo
4.
Occup Environ Med ; 55(3): 180-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9624269

RESUMO

OBJECTIVES: To study the determinants of signs of carpal tunnel syndrome (CTS) in repetitive industrial work, with special attention to occupational constraints at group level and management practices of the companies. METHOD: A cross sectional study was conducted in three sectors: assembly line; clothing and shoe industry; food industry. A total of 1210 workers in repetitive work, from 53 different companies, was compared with a control group of 337 workers. Constraints at the workplace were partly self declared, and partly assessed by the occupational physicians in charge of the employees of the company. The definition of CTS was based on a standardised clinical examination. RESULTS: CTS was associated with repetitive work, especially packaging. It was more frequent among subjects who declared psychological and psychosomatic problems and those with a body mass index > or = 27. Dissatisfaction with work, lack of job control, short cycle time, and having to press repeatedly with the hand were associated with the syndrome. An odds ratio (OR) of 2.24 was found for "just in time" production. CONCLUSION: The results emphasise the complexity of the determinants of CTS, the role of psychosocial factors at work and the potentially negative effects of some practices of the companies aimed at enhancing their competitiveness.


Assuntos
Síndrome do Túnel Carpal/etiologia , Adulto , Índice de Massa Corporal , Síndrome do Túnel Carpal/epidemiologia , Síndrome do Túnel Carpal/psicologia , Vestuário , Estudos Transversais , Transtornos Traumáticos Cumulativos/epidemiologia , Transtornos Traumáticos Cumulativos/etiologia , Transtornos Traumáticos Cumulativos/psicologia , Feminino , Indústria Alimentícia , França/epidemiologia , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Doenças Profissionais/psicologia , Embalagem de Produtos , Fatores de Risco , Indústria Têxtil , Tolerância ao Trabalho Programado
5.
Rev Fr Transfus Hemobiol ; 35(3): 205-10, 1992 Jul.
Artigo em Francês | MEDLINE | ID: mdl-1329793

RESUMO

Hepatitis C virus (HCV) discovery and introduction of anti-HCV antibodies screening in blood transfusion imply the necessity of a good blood donations and blood donors policy. Detection of a seropositivity during the screening must be completed with a confirmatory test. The results are directly used to inform donors and define the blood products policy. Donors with positive results on confirmatory test are discarded and have physical and biological examinations in hepatology. Individuals with indeterminate or negative results must be retested for the HCV serology. Furthermore, because of a rapid improvement in the fields of technology, diagnosis and therapy of HCV, an adaptation of the policy is necessary.


Assuntos
Doadores de Sangue , Transfusão de Sangue/normas , Política de Saúde , Anticorpos Anti-Hepatite/sangue , Hepatite C/prevenção & controle , Programas de Rastreamento , França , Hepacivirus/imunologia , Hepatite C/transmissão , Humanos , Reação Transfusional
6.
Rev Fr Transfus Hemobiol ; 35(3): 171-82, 1992 Jul.
Artigo em Francês | MEDLINE | ID: mdl-1384522

RESUMO

Anti-HCV systematic screening on blood donation was mandatory in France since first of March 1991. Two laboratories (Ortho-Chiron and Abbott) have introduced in Europe successively two kinds of hepatitis C positive diagnosis with 1st and 2nd generation ELISA screening and confirmatory assays. The aim of this multicentric study was to evaluated the sensibility and specificity of these tests. For that, they used 10,090 blood sera. As a result we have seen that the new "second generation" screening assays have a higher sensitivity without less of specificity for the confirmatory tests.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite C/prevenção & controle , Immunoblotting , Programas de Rastreamento/métodos , Kit de Reagentes para Diagnóstico , Antígenos Virais/imunologia , Doadores de Sangue , Hepatite C/diagnóstico , Anticorpos Anti-Hepatite C , Humanos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Transfusion ; 31(9): 792-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1755082

RESUMO

To evaluate accurately the current performance of filtration, the French Produits Sanguins Labiles study group, composed of 21 transfusion teams, conducted a large-scale 6-month study involving over 1400 filtrations and 3000 controls. Some 745 standard red cell concentrates (RBC concentrates) and 690 concentrates previously white cell (WBC)-reduced by removal of buffy coat (BC-poor RBC concentrates) were filtered using six commercially available filters: at least 170 results were collected per filter, spread among a minimum of three teams. Prefiltration controls show that the removal (manual and automated) of the buffy coat results in an initial WBC reduction of approximately 63 percent, along with a hemoglobin loss of 4 g (7%). After filtration, residual WBCs were counted in the Nageotte manual counting chamber. The reliability of this counting method, which is simple and adapted to low WBC concentrations, was characterized in this study by a 25-percent coefficient of variation (CV) for a concentration of 2.5 WBCs per microL (i.e, 0.6 x 10(6) WBCs/filtered unit). The analysis of the results shows that, for five of six filters (1 filter was excluded), the postfiltration median value of residual WBCs was 1.1 x 10(6) in filtered RBC concentrates (n = 590), whereas it was 0.34 x 10(6) in filtered BC-poor RBC concentrates (n = 581). The difference is significant (p less than 10(-8), Wilcoxon test). Hemoglobin loss due to filtration varies according to the filter, from 5.7 +/- 2.2 to 17.3 +/- 2.5 g.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Remoção de Componentes Sanguíneos/métodos , Eritrócitos , Contagem de Leucócitos , Filtração , Hemoglobinas/análise , Humanos
8.
Rev Fr Transfus Hemobiol ; 34(4): 285-94, 1991 Jul.
Artigo em Francês | MEDLINE | ID: mdl-1910349

RESUMO

By now in France HBV seric markers (Ag HBs and Ac HBc) and transaminases level (ALT) screenings are compulsory by law in blood donors. People whose blood donation is discarded should be informed. A clinical, epidemiological and virological survey of such donors is required to differentiate healthy Ag HBs carriers and patients suffering from hepatitis B (who may eventually be treated). Similar guidelines may be recommended for the blood donors presenting high transaminases level without HBV seric markers in order to find a cause for such impaired biochemical tests: overweight, alcohol, drug consumption, auto-immune liver disease, genetic disorder, Non-A, Non-B, Non-C hepatitis....


Assuntos
Doadores de Sangue , Anticorpos Anti-Hepatite/análise , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/análise , Hepatite B/diagnóstico , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Conhecimentos, Atitudes e Prática em Saúde , Hepatite/diagnóstico , Hepatite C/diagnóstico , Humanos , Educação de Pacientes como Assunto , Testes Sorológicos
10.
Rev Mal Respir ; 7(1): 31-7, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2251432

RESUMO

We have analysed the symptoms and respiratory function of a group of cheese processors making gruyère Comté in relation to a group of controls: 96 male cheese workers (mean age 36 +/- 11.1) and 97 controls who were of the male sex and of comparable age, height, weight and smoking habits. The cheese workers had a lower educational and professional level (p less than 0.01) and had a higher level of alcohol consumption than the controls (p less than 0.05). The prevalence of chronic bronchitis and of dyspnoea in the cheese workers (respectively 13.5 and 23.9%) was not significantly different from that in the controls (10.3 and 35%). 5 cheese workers (5.2%) were suspected of having occupational asthma; 5 (5.2%) were suspected of having hypersensitivity pneumonia (cheese workers' disease): 41 (42.7%) had signs of conjunctivitis during work, of whom 30 occurred only in the hot cellars. The respiratory function parameters measured were identical in the two groups (vital capacity, FEV1, mean expiratory flow at 25% and 75% of vital capacity). In conclusion, evidence of allergic problems (asthma, hypersensitivity pneumonia and conjunctivitis) seems to be frequent in refiners of Comté but the cases identified need to be confirmed; cheese refiners of Comté do not seem to have any particular risks of chronic bronchitis and of alteration of respiratory function.


Assuntos
Queijo , Manipulação de Alimentos , Pneumopatias/epidemiologia , Doenças Profissionais/epidemiologia , Transtornos Respiratórios/epidemiologia , Adulto , Alveolite Alérgica Extrínseca/epidemiologia , Bronquite/epidemiologia , França/epidemiologia , Humanos , Pneumopatias/fisiopatologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/fisiopatologia , Transtornos Respiratórios/fisiopatologia , Fumar/epidemiologia , Espirometria
11.
Chir Pediatr ; 25(1): 37-42, 1984.
Artigo em Francês | MEDLINE | ID: mdl-6539656

RESUMO

Foetus in foetu is a very unusual cause of abdominal mass in the infancy. Twenty cases only have been quoted in the literature. Two others cases are added, concerning two girls: a three months infant, second born from a genuine twin pregnancy, and a four weeks newborn whose the mass was discovered before the birth, on routine ultrasonography. In together, the diagnosis was made in operating room, then confirmed by pathologic studies. Literature data are recorded, and the difference between teratomas and foetus in foetu is point. The pathogeny remains obscure. It could result from the inclusion of a parasite twin in his bearer, become during embryologic stage of the delimitation.


Assuntos
Morte Fetal/diagnóstico , Reabsorção do Feto/diagnóstico , Neoplasias Retroperitoneais/diagnóstico , Teratoma/diagnóstico , Gêmeos Unidos/embriologia , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Lactente , Cariotipagem , Gravidez , Espaço Retroperitoneal , Gêmeos Monozigóticos , Ultrassonografia , Urografia
12.
In Vitro ; 18(9): 739-49, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7173948

RESUMO

A human cell line has been established from a transplantable xenografted human testicular tumor, which, both in the original tumor and in the xenograft, exhibited the histological characteristics of an undifferentiated malignant teratoma (embryonal cell carcinoma). The cells in culture were undifferentiated by biochemical, morphological, and ultrastructural criteria, growing as small islands of cells that tended to form aggregates at high density. The cells showed some variation in chromosome number with 30 to 40% of the cells having a normal human karyotype. The cells expressed high levels of alkaline phosphatase, which by heat inactivation and inhibition studies was 40 to 50% placental type alkaline phosphatase. None of the cultures produced human chorionic gonadotrophin, alphafetoprotein, carcinoembryonic antigen, or fibronectin, although at high cell densities plasminogen activator could be detected at low levels. Cell surface studies showed that the cells shared antigens with the murine embryonal carcinoma cell line F9, expressed beta 2-microglobulin at very low and variable levels, and bound the lectin peanut agglutinin. These studies suggest that this cell line has some of the characteristics described for murine embryonal carcinoma cell lines.


Assuntos
Linhagem Celular , Teratoma/patologia , Neoplasias Testiculares/patologia , Fosfatase Alcalina/análise , Humanos , Isoenzimas , Cariotipagem , L-Lactato Desidrogenase/análise , Masculino , Metástase Neoplásica , Teratoma/enzimologia , Neoplasias Testiculares/enzimologia
14.
Cancer Res ; 41(4): 1422-7, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6163522

RESUMO

Monolayer cultures of nine human testicular germ cell tumors have been attempted, and five have been established as proliferating long-term cultures. All five grew in suspension in nutrient agar, but three proliferated in monolayer culture only when in contact with stromal cells derived from the tumors. Two have been established as "pure" lines, and one of these has been cloned. All contain elevated levels of alkaline phosphatase, approximately one-half of which displays placental isoenzymic characteristics. Three tumor cultures formed differentiated tissues and synthesized significant quantities of beta-chorionic gonadotrophin or carcinoembryonic antigen for a brief period after a 5-month culture. These properties were subsequently lost and could not be reinduced.


Assuntos
Linhagem Celular , Disgerminoma/patologia , Neoplasias Testiculares/patologia , Fosfatase Alcalina/análise , Antígeno Carcinoembrionário/análise , Divisão Celular , Gonadotropina Coriônica/análise , Técnicas Citológicas , Disgerminoma/metabolismo , Humanos , Masculino , Ativadores de Plasminogênio/análise , Neoplasias Testiculares/metabolismo , Fatores de Tempo , alfa-Fetoproteínas/análise
15.
In Vitro ; 16(8): 639-46, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7419234

RESUMO

The preparation of highly purified monolayer cultures of human cytotrophoblast cells essentially free of stromal and syncytial cells is described. Such cells subsequently form multinucleate syncytial cells in vitro. This is accompanied by the synthesis of heat-stable alkaline phosphatase and beta-HCG. A significant proportion of the multinucleate cells that form in monolayer cultures of early placentae arise as a result of an amitosis. It is suggested that this in vitro behavior may reflect an in vivo process.


Assuntos
Trofoblastos/citologia , Fosfatase Alcalina/biossíntese , Divisão Celular , Membrana Celular/ultraestrutura , Movimento Celular , Separação Celular , Células Cultivadas , Gonadotropina Coriônica/biossíntese , Feminino , Humanos , Gravidez , Trofoblastos/metabolismo
19.
Gut ; 12(3): 194-6, 1971 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-5552187

RESUMO

The behaviour of the juvenile polyp in vitro and its cellular development from explants have been studied using cellular dispersion by the trypsinization technique. Only the fibroblastic cells have been found to grow. The significance of this finding suggests that the juvenile polyp is a hamartoma.


Assuntos
Técnicas de Cultura , Pólipos Intestinais/patologia , Neoplasias Retais/patologia , Criança , Pré-Escolar , Fibroblastos/citologia , Hamartoma/patologia , Humanos , Lactente , Tripsina
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