Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
J Struct Biol ; 215(4): 108038, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37858875

RESUMEN

Transcription of specific genes in bacteria under environmental stress is frequently initiated by extracytoplasmic function (ECF) σ factors. ECFs σ factors harbour two conserved domains, σ2 and σ4, for transcription initiation by recognition of the promoter region and recruitment of RNA polymerase (RNAP). The crystal structure of Streptomyces tsukubaensis SigG1, an ECF56-family σ factor, was determined revealing σ2, σ4 and the additional carboxi-terminal domain SnoaL_2 tightly packed in a compact conformation. The structure of anti-sigma RsfG was also determined by X-ray crystallography and shows a rare ß-barrel fold. Analysis of the metal binding motifs inside the protein barrel are consistent with Fe(III) binding, which is in agreement with previous findings that the Streptomyces tsukubaensis ECF56 SigG1-RsfG system is involved in metal-ion homeostasis.


Asunto(s)
Factor sigma , Streptomyces , Factor sigma/genética , Factor sigma/química , Factor sigma/metabolismo , Proteínas Bacterianas/química , Compuestos Férricos , Modelos Moleculares , Streptomyces/genética , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/química , Regulación Bacteriana de la Expresión Génica
2.
Eur Thyroid J ; 11(4)2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35900859

RESUMEN

Objective: To understand whether thyroid cells can be directly infected by the SARS-CoV-2 virus and to establish a putative correlation with the expression of the host entry machinery: ACE-2, TMPRSS2, and furin. Methods: We assessed the presence of SARS-CoV-2 virus at the gene level by RT-PCR, viral RNA transcripts localization by in situ hybridization, and by detecting viral proteins by immunohistochemistry for the nucleocapsid and the spike proteins. Furthermore, we also described the immunoexpression of key host factors for virus entry in the COVID-19 thyroid samples. Results: We performed RT-PCR for SARS-CoV-2 in all autopsy specimens and detected viral genome positivity in 13 of 15 thyroid tissues and in a lung specimen. In 9 of the 14 positive samples, we were also able to confirm SARS-CoV-2 signal by in situ hybridization. Immunohistochemistry for the viral nucleocapsid and spike protein was also positive for ten and nine of the RT-PCR-positive cases, respectively, but revealed a lower sensitivity. We also described, for the first time in a COVID-19 series, the immunohistochemical expression of ACE-2, TMPRSS2, and furin in the thyroid. Conclusions: Our results obtained in thyroid specimens from deceased COVID-19 patients indicate that thyrocytes can be directly infected by SARS-CoV-2 since we detected the presence of SARS-CoV-2 genome in follicular cells. Nevertheless, we did not find a clear correlation between the presence of viral genome and the expression of the host factors for virus entry, namely ACE-2, TMPRSS2, and furin.

3.
Chaos ; 32(5): 053126, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35649974

RESUMEN

In the realm of Boltzmann-Gibbs statistical mechanics, there are three well known isomorphic connections with random geometry, namely, (i) the Kasteleyn-Fortuin theorem, which connects the λ → 1 limit of the λ-state Potts ferromagnet with bond percolation, (ii) the isomorphism, which connects the λ → 0 limit of the λ-state Potts ferromagnet with random resistor networks, and (iii) the de Gennes isomorphism, which connects the n → 0 limit of the n-vector ferromagnet with self-avoiding random walk in linear polymers. We provide here strong numerical evidence that a similar isomorphism appears to emerge connecting the energy q-exponential distribution ∝ e (with q = 4 / 3 and ß ω = 10 / 3) optimizing, under simple constraints, the nonadditive entropy S with a specific geographic growth random model based on preferential attachment through exponentially distributed weighted links, ω being the characteristic weight.

4.
Cancers (Basel) ; 14(11)2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35681562

RESUMEN

SARS-CoV-2 pandemics have been massively characterized on a global scale by the rapid generation of in-depth genomic information. The main entry gate of SARS-CoV-2 in human cells is the angiotensin-converting enzyme 2 (ACE2) receptor. The expression of this protein has been reported in several human tissues, suggesting a correlation between SARS-CoV-2 organotropism and ACE2 distribution. In this study, we selected (a series of) 90 patients who were submitted to surgery for tumor removal between the beginning of the SARS-CoV-2 pandemic and the closure of operating rooms (by the end of March 2020) in two different countries-Portugal and Brazil. We evaluated the expressions of ACE2 and furin (another important factor for virus internalization) in colon (n = 60), gastric (n = 19), and thyroid (n = 11) carcinomas. In a subseries of cases with PCR results for SARS-CoV-2 detection in the peri-operatory window (n = 18), we performed different methodological approaches for viral detections in patient tumor samples. Our results show that colon and gastric carcinomas display favorable microenvironments to SARS-CoV-2 tropism, presenting high expression levels of ACE2 and furin. From the subseries of 18 cases, 11 tested positive via PCR detection performed in tumor blocks; however, a direct association between the ACE2 expression and SARS-CoV-2 infection was not demonstrated in cancer cells using histology-based techniques, such as immunohistochemistry or in situ hybridization. This study raises the possibility of ACE2-mediated viral tropism in cancer tissues to be clarified in future studies.

5.
Sci Rep ; 10(1): 21728, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-33303917

RESUMEN

Extracytoplasmic function (ECF) sigma factors are key transcriptional regulators that prokaryotes have evolved to respond to environmental challenges. Streptomyces tsukubaensis harbours 42 ECFs to reprogram stress-responsive gene expression. Among them, SigG1 features a minimal conserved ECF σ2-σ4 architecture and an additional C-terminal extension that encodes a SnoaL_2 domain, which is characteristic for ECF σ factors of group ECF56. Although proteins with such domain organisation are widely found among Actinobacteria, the functional role of ECFs with a fused SnoaL_2 domain remains unknown. Our results show that in addition to predicted self-regulatory intramolecular amino acid interactions between the SnoaL_2 domain and the ECF core, SigG1 activity is controlled by the cognate anti-sigma protein RsfG, encoded by a co-transcribed sigG1-neighbouring gene. Characterisation of ∆sigG1 and ∆rsfG strains combined with RNA-seq and ChIP-seq experiments, suggests the involvement of SigG1 in the morphological differentiation programme of S. tsukubaensis. SigG1 regulates the expression of alanine dehydrogenase, ald and the WhiB-like regulator, wblC required for differentiation, in addition to iron and copper trafficking systems. Overall, our work establishes a model in which the activity of a σ factor of group ECF56, regulates morphogenesis and metal-ions homeostasis during development to ensure the timely progression of multicellular differentiation.


Asunto(s)
Proteínas Bacterianas/fisiología , Homeostasis/genética , Hierro/metabolismo , Factor sigma/fisiología , Streptomyces/genética , Streptomyces/fisiología , Transformación Bacteriana/genética , Regulación Bacteriana de la Expresión Génica , Streptomyces/metabolismo
6.
Antibiotics (Basel) ; 9(10)2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33076498

RESUMEN

The oxidative stress response is a key mechanism that microorganisms have to adapt to changeling environmental conditions. Adaptation is achieved by a fine-tuned molecular response that extends its influence to primary and secondary metabolism. In the past, the role of the intracellular redox status in the biosynthesis of tacrolimus in Streptomyces tsukubaensis has been briefly acknowledged. Here, we investigate the impact of the oxidative stress response on tacrolimus biosynthesis in S. tsukubaensis. Physiological characterization of S. tsukubaensis showed that the onset of tacrolimus biosynthesis coincided with the induction of catalase activity. In addition, tacrolimus displays antioxidant properties and thus a controlled redox environment would be beneficial for its biosynthesis. In addition, S. tsukubaensis ∆ahpC strain, a strain defective in the H2O2-scavenging enzyme AhpC, showed increased production of tacrolimus. Proteomic and transcriptomic studies revealed that the tacrolimus over-production phenotype was correlated with a metabolic rewiring leading to increased availability of tacrolimus biosynthetic precursors. Altogether, our results suggest that the carbon source, mainly used for cell growth, can trigger the production of tacrolimus by modulating the oxidative metabolism to favour a low oxidizing intracellular environment and redirecting the metabolic flux towards the increase availability of biosynthetic precursors.

7.
Sci Rep ; 5: 12887, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26256439

RESUMEN

Streptomyces are aerobic Gram-positive bacteria characterized by a complex life cycle that includes hyphae differentiation and spore formation. Morphological differentiation is triggered by stressful conditions and takes place in a pro-oxidant environment, which sets the basis for an involvement of the oxidative stress response in this cellular process. Characterization of the phenotypic traits of Streptomyces natalensis ΔkatA1 (mono-functional catalase) and ΔcatR (Fur-like repressor of katA1 expression) strains in solid medium revealed that both mutants had an impaired morphological development process. The sub-lethal oxidative stress caused by the absence of KatA1 resulted in the formation of a highly proliferative and undifferentiated vegetative mycelium, whereas de-repression of CatR regulon, from which KatA1 is the only known representative, resulted in the formation of scarce aerial mycelium. Both mutant strains had the transcription of genes associated with aerial mycelium formation and biosynthesis of the hyphae hydrophobic layer down-regulated. The first round of the programmed cell death (PCD) was inhibited in both strains which caused the prevalence of the transient primary mycelium (MI) over secondary mycelium (MII). Our data shows that the first round of PCD and morphological differentiation in S. natalensis is dependent on oxidative stress in the right amount at the right time.


Asunto(s)
Apoptosis , Estrés Oxidativo , Streptomyces/fisiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Catalasa/genética , Catalasa/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo , Electroforesis en Gel Bidimensional , Genoma Bacteriano , Secuenciación de Nucleótidos de Alto Rendimiento , Viabilidad Microbiana , Microscopía Confocal , Micelio/metabolismo , Estrés Oxidativo/genética , Reacción en Cadena de la Polimerasa , Proteoma/análisis , Esporas Bacterianas , Streptomyces/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
8.
BMC Genomics ; 15: 371, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24885229

RESUMEN

BACKGROUND: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. RESULTS: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org. CONCLUSIONS: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.


Asunto(s)
Etiquetas de Secuencia Expresada , Quercus/genética , Transcriptoma , ADN de Plantas/análisis , Biblioteca de Genes , Filogenia , Quercus/crecimiento & desarrollo , Análisis de Secuencia de ADN
9.
Rev Bras Epidemiol ; 14(3): 467-77, 2011 Sep.
Artículo en Portugués | MEDLINE | ID: mdl-22069014

RESUMEN

INTRODUCTION: Sexually Transmitted Infections (STIs) in women remain a public health challenge due to high prevalence, difficulties to implement early diagnosis strategies and high rates of complications. OBJECTIVE: Identify the prevalence of STIs among users of a primary health care clinic in São Paulo. METHODS: Women, 18 to 40 years of age, were invited to self-collect vaginal specimens to be tested for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis by Polymerase Chain Reaction (PCR). Women were also invited to answer a demographic and sexual history questionnaire, either on the computer or face-to-face. RESULTS: The prevalence of STIs obtained from the 781 women included in the study was: Chlamydia trachomatis: 8.4%, Neisseria gonorrhoeae: 1.9%, and Trichomonas vaginalis: 3.2%. Thirteen percent tested positive for at least one out of the three STIs. The variables associated independently with a higher risk of STIs were: age under 20-years-old, more than two lifetime sexual partners, and self-perception of STI risk. The use of condoms as a contraceptive method proved to be a protective factor. CONCLUSION: The high prevalence found among these women indicates the need for the implementation of STI screening strategies in primary care settings in Brazil.


Asunto(s)
Enfermedades de Transmisión Sexual/diagnóstico , Adulto , Brasil , Diagnóstico Precoz , Femenino , Humanos , Prevalencia , Atención Primaria de Salud , Enfermedades de Transmisión Sexual/epidemiología , Encuestas y Cuestionarios , Adulto Joven
10.
Rev. bras. epidemiol ; 14(3): 467-477, set. 2011. tab
Artículo en Portugués | LILACS | ID: lil-604619

RESUMEN

INTRODUÇÃO: Infecções Sexualmente Transmissíveis (IST) em mulheres permanecem um desafio para a Saúde Pública: elevada prevalência, dificuldade para implantação de estratégias de diagnóstico precoce e elevada ocorrência de sequelas. OBJETIVO: Identificar a prevalência de IST em usuárias de um serviço de atenção primária à saúde em São Paulo. MÉTODOS: Mulheres de 18 a 40 anos foram convidadas para realizar autocoleta de secreção vaginal para a detecção de Chlamydia trachomatis, Neisseria gonorrhoeae e Trichomonas vaginalis por meio de Reacão em Cadeia da Polimerase (PCR). As mulheres também responderam a um questionário com questões demográficas e relativas à história sexual face a face ou autoaplicado por meio de um computador. RESULTADOS: Das 781 mulheres incluídas no estudo, as prevalências obtidas foram: Chlamydia trachomatis (8,4 por cento), Neisseria gonorrhoeae (1,9 por cento) e Trichomonas vaginalis (3,2 por cento). A positividade para pelo menos uma das três IST foi de 13 por cento. As variáveis associadas independentemente com maior risco de IST foram: idade menor que 20 anos, mais de dois parceiros sexuais na vida e percepção de risco para IST; o uso de preservativo como método contraceptivo foi um fator protetor. CONCLUSÃO: A prevalência encontrada em usuárias indica a necessidade da implantação de estratégias de rastreamento de IST em serviços de atenção primária.


INTRODUCTION: Sexually Transmitted Infections (STIs) in women remain a public health challenge due to high prevalence, difficulties to implement early diagnosis strategies and high rates of complications. OBJECTIVE: Identify the prevalence of STIs among users of a primary health care clinic in São Paulo. METHODS: Women, 18 to 40 years of age, were invited to self-collect vaginal specimens to be tested for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis by Polymerase Chain Reaction (PCR). Women were also invited to answer a demographic and sexual history questionnaire, either on the computer or face-to-face. RESULTS: The prevalence of STIs obtained from the 781 women included in the study was: Chlamydia trachomatis: 8.4 percent, Neisseria gonorrhoeae: 1.9 percent, and Trichomonas vaginalis: 3.2 percent. Thirteen percent tested positive for at least one out of the three STIs. The variables associated independently with a higher risk of STIs were: age under 20-years-old, more than two lifetime sexual partners, and self-perception of STI risk. The use of condoms as a contraceptive method proved to be a protective factor. CONCLUSION: The high prevalence found among these women indicates the need for the implementation of STI screening strategies in primary care settings in Brazil.


Asunto(s)
Adulto , Femenino , Humanos , Adulto Joven , Enfermedades de Transmisión Sexual/diagnóstico , Brasil , Diagnóstico Precoz , Prevalencia , Atención Primaria de Salud , Encuestas y Cuestionarios , Enfermedades de Transmisión Sexual/epidemiología
11.
BIS, Bol. Inst. Saúde (Impr.) ; 13(2): 177-181, out. 2011.
Artículo en Portugués | Sec. Est. Saúde SP, SESSP-ISPROD, Sec. Est. Saúde SP, SESSP-ISACERVO | ID: biblio-1047490

RESUMEN

Fluxos migratórios hoje se constituem como uma questão social. Provocados por determinações políticas, econômicas, religiosas etc., resultam em impactos sociais. O Brasil destaca-se no cenário econômico, atraindo populações vizinhas por melhores condições de vida para grandes cidades, como é o caso de São Paulo, inserindo-se, a maioria, de forma precária. O maior contingente migratório é boliviano, com acentuada situação de vulnerabilidade e exclusão social, demandando cuidados específicos para proteção da saúde. Nesse contexto, o debate torna-se necessário para as políticas públicas e, dentre elas, as de saúde, referenciadas no Sistema Único de Saúde. Esse artigo objetiva descrever experiência em Atenção Primária à Saúde aos bolivianos que vivem no centro da cidade de São Paulo. É fundamental incorporar, no cuidado, questões relacionadas à identidade cultural, à desigualdade de gênero e à territorialização. Os programas de saúde, em geral, não são resolutivos para esse grupo. O "cardápio" que os serviços de saúde oferecem não provoca vínculos e não reconhece suas necessidades, particularmente em relação às mulheres, em maior vulnerabilidade ­ violências domésticas e no trabalho. Identificar as situações de vulnerabilidades, valorizando suas identidades, reconhecendo suas necessidades, entre outros elementos, tem nos pautado na organização do cuidado desse grupo, favorecendo, desse modo, a proteção e promoção da saúde e a inclusão social.


Asunto(s)
Humanos , Atención Primaria de Salud , Marginación Social , Migración Humana
12.
Cien Saude Colet ; 15 Suppl 1: 1377-81, 2010 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-20640297

RESUMEN

Data from the Brazilian Ministry of Health shows that the breast cancer is one of the leading causes of women's death, despite the enhancements in treatment and diagnosis of this disease. Successive explanatory advertising campaigns emphasized the methods available for prevention: auto examination, clinical examination by a health care professional and mammography. Regardless of their relevance, only these strategies did not reduced incidence of breast cancer, since they do not impact on the oncogenesis factors. The objective of this article is to develop a health promotion activity through the reinforcement of the previous knowledge and aggregation of new information about breast cancer of a basic health unit. The methodology used was a transversal study of pedagogical intervention in the waiting rooms of a basic health unit. The pedagogical intervention was composed by an interactive questionnaire, lecture and discussion about the topic associated with a qualitative and quantitative evaluation of the activity. The proposed activity had positive results since the participants had qualitative and quantitative improvement in their knowledge and also a good interactivity with the researchers.


Asunto(s)
Neoplasias de la Mama/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Salud Pública , Encuestas y Cuestionarios
13.
Ciênc. Saúde Colet. (Impr.) ; 15(supl.1): 1377-1381, jun. 2010. tab
Artículo en Portugués | LILACS | ID: lil-555670

RESUMEN

No Brasil, dados do Ministério da Saúde apontam o câncer de mama como principal causa de morte em mulheres, apesar dos avanços no diagnóstico e tratamento desta enfermidade. Sucessivas campanhas de esclarecimento à população enfatizaram os meios disponíveis para prevenção: autoexame, exame clínico por profissional da saúde e a mamografia. Apesar da sua importância, estas estratégias isoladamente não reduziram a incidência deste agravo à saúde, já que não atuam nos fatores predisponentes para sua iniciação. O objetivo desse estudo foi desenvolver uma atividade de promoção à saúde através do reforço de conhecimentos existentes e agregação de novas informações sobre o câncer de mama no contexto de Unidade Básica de Saúde. Trata-se de um estudo transversal de intervenção pedagógica em salas de espera de Unidade Básica de Saúde. A intervenção pedagógica foi realizada através de questionário interativo, palestra informativa e discussão livre sobre o tópico, associados à avaliação quantitativa e qualitativa desta intervenção. A abordagem proposta foi positiva, uma vez que houve melhora quantitativa e qualitativa da compreensão do público sobre os temas abordados, boa interatividade entre os palestrantes e o público, e criação de agentes multiplicadores de conhecimento.


Data from the Brazilian Ministry of Health shows that the breast cancer is one of the leading causes of women's death, despite the enhancements in treatment and diagnosis of this disease. Successive explanatory advertising campaigns emphasized the methods available for prevention: auto examination, clinical examination by a health care professional and mammography. Regardless of their relevance, only these strategies did not reduced incidence of breast cancer, since they do not impact on the oncogenesis factors. The objective of this article is to develop a health promotion activity through the reinforcement of the previous knowledge and aggregation of new information about breast cancer of a basic health unit. The methodology used was a transversal study of pedagogical intervention in the waiting rooms of a basic health unit. The pedagogical intervention was composed by an interactive questionnaire, lecture and discussion about the topic associated with a qualitative and quantitative evaluation of the activity. The proposed activity had positive results since the participants had qualitative and quantitative improvement in their knowledge and also a good interactivity with the researchers.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Neoplasias de la Mama/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Estudios Transversales , Salud Pública , Encuestas y Cuestionarios
14.
Gynecol Endocrinol ; 20(5): 249-57, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16019369

RESUMEN

OBJECTIVE: The aim of the study was to investigate the impact of the climacterium (before and after menopause) on platelet activation. BACKGROUND: Platelet activation has been associated to the risk of cardiovascular disease. There is much speculation about the relationship between platelet function and sex steroids, due to peculiarities of platelet action between the genders, including concerns about the influence of low estradiol status in menopausal women. METHODS: By means of a cross-sectional study design, 37 female patients divided into two groups were compared. Group A consisted of ten women, mean age 43.9 years, in the premenopausal period, with normal estrogen levels; and Group B comprised 27 patients, mean age 53.0 years, who had all reached menopause. Platelet activation markers, namely P-selectin and glycoprotein IIb-IIIa complex (GPIIb-IIIa), were evaluated by flow cytometry with monoclonal antibodies. A binding index was calculated for both parameters (percentage of positive platelets x mean fluorescence of positive platelets). Also, thromboxane A2 was quantified by means of its main plasma metabolite, thromboxane B2, by enzyme immunoassay. RESULTS: P-selectin and GPIIb-IIIa expression results revealed lower platelet activation status after menopause, as there was a decrease in both the percentage of P-selectin+ platelets and of GPIIb-IIIa mean fluorescence of positive platelets, lowering both binding indices. P-selectin binding index differed significantly between Group A (12.3 +/- 3, n = 10) and Group B (6.2 +/- 2.9, n = 27; mean +/- standard deviation (SD), p < 0.001). GPIIb-IIIa binding index also differed significantly between both groups (Group A: 18.8 +/- 2.3, n = 10 vs. Group B: 16.2 +/- 3.1, n = 27; mean +/- SD, p < 0.0018). Plasma concentration of thromboxane B2 was 1.07 +/- 0.5 pg/well before menopause (Group A, n = 10) and 1.9 +/- 4.1 pg/well after menopause (Group B, n = 27), not significantly different (mean +/- SD, baseline x therapy, p = 0.85). CONCLUSIONS: After the menopause, climacteric women--whose estradiol status is low--have a decreased activation platelet status compared with premenopausal women. Nevertheless, further studies on a larger sample are necessary for conclusive data regarding cardiovascular disease.


Asunto(s)
Menopausia/sangre , Activación Plaquetaria , Adulto , Anciano , Anticuerpos Monoclonales , Estudios Transversales , Femenino , Citometría de Flujo , Humanos , Modelos Logísticos , Persona de Mediana Edad , Selectina-P/sangre , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo
15.
Int J Cardiol ; 99(3): 449-54, 2005 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-15771927

RESUMEN

OBJECTIVE: This study shows the effect of hormone replacement therapy (HRT), using oral estrogen exclusively or in combination with progestin, on platelet activation in healthy menopaused women. BACKGROUND: Recent evidence from studies of postmenopausal HRT in healthy women demonstrated a short-time increased risk of coronary heart disease. Platelet activation, which generates vasoconstrictory thromboxane A(2) (TxA(2)), has been related to the risk of cardiovascular diseases. METHODS: By means of a placebo-controlled study twenty-seven postmenopausal patients were continuously orally administered estrogen in combination with progestin or estrogen exclusively for an 8-week period. Platelet activation was evaluated by flow cytometric P-selectin expression and by enzyme immunoassay plasmatic TxA(2) (TxB(2)) concentrations. RESULTS: P-selectin binding index changed from 6.3+/-3.6 to 7.0+/-3 in the placebo group (n=10); from 5.9+2.2 to 7.9+/-3.3 in the E+P group (n=8) and from 6.4+2.7 to 7.1+/-1.9 in the E group (n=9). Plasma concentrations of TxB(2) before and after intervention, changed from 1.2+1.2 to 1.5+1.4 (pg/well) in the placebo group; significantly (p=0.005) in the E+P group (n=8), from 0.9+0.3 to 6.1+6.5 (pg/well), and from 1.3+1.5 to 0.8+0.4 (pg/well) in the E group (n=8; mean+standard deviation, basal x therapy, p<0.05). CONCLUSIONS: Healthy menopaused women who were administered estradiol in association with norethisterone continuously had an increase of plasmatic thromboxane, possibly determined by platelet activation, which indicates a higher short-term thrombotic risk. P-selectin expression analyses failed to demonstrate the impact of HRT on platelets.


Asunto(s)
Terapia de Reemplazo de Estrógeno , Activación Plaquetaria/efectos de los fármacos , Tromboxano B2/sangre , Anciano , Estrógenos/farmacología , Femenino , Humanos , Persona de Mediana Edad , Selectina-P/sangre , Activación Plaquetaria/fisiología , Progestinas/farmacología
16.
Rev. bras. hematol. hemoter ; 25(3): 161-168, July-Sept. 2003. tab
Artículo en Portugués | LILACS | ID: lil-355439

RESUMEN

A variante de hemoglobina (Hb) D mais comum, Hb D Los Angeles ou D Punjab, é originada de uma transversão GAA->CAA no códon 121 da globina beta; essa mutação resulta na substituição do ácido glutâmico por glutamina na proteína. É a terceira variante de hemoglobina mais freqüente da população brasileira. Como as hemoglobinas D apresentam migração similar à hemoglobina S em pH alcalino, e com a hemoglobina A em pH ácido, são necessários vários testes para o correto diagnóstico. No presente estudo objetivou-se relacionar os diferentes procedimentos laboratoriais de rotina diagnóstica, além da análise molecular, para estabelecer o perfil de Hb D Los Angeles no Brasil. Foram analisados 47 indivíduos da população brasileira com provável Hb D Los Angeles, por vários procedimentos eletroforéticos em diferentes condições de pH, além da cromatografia líquida de alta pressão, e testes moleculares para confirmação da mutação. Foram encontrados quatro tipos de combinações de hemoglobinas: 42 indivíduos portadores de hemoglobina AD Los Angeles, dois indivíduos com doença de Hb S/D Los Angeles, dois indivíduos com Hb D Los Angeles e talassemia beta e um indivíduo com Hb D Los Angeles e Hb Lepore. Os indivíduos heterozigotos para D Los Angeles são assintomáticos, entretanto, em associação com outras variantes e talassemias podem apresentar graus variáveis de manifestações clínicas. Os resultados apresentados enfatizaram a necessidade da associação de várias metodologias para a identificação da Hb D Los Angeles, além de auxiliar na elucidação de combinações raras


The most common Hb D variant, the Hb D-Los Angeles,also know as Hb D-Punjab, originates through aGAA¨CAA change at the 121 codon of the ƒÀ globingene; this mutation results in the replacement ofglutamic acid for glutamine in the protein. It is thethird most common hemoglobin variant in theBrazilian population. This variant has electrophoreticmigration in alkaline pHs similar to Hb S and identicalmigration to hemoglobin A in acidic pHs. Thus, severaltechniques are necessary for its correct diagnosis. Thepurpose of this work was to relate the differentlaboratorial techniques and molecular analyses to determinethe profile of Hb D Los Angeles in Brazil. Fortysevenindividuals from the Brazilian population withHb D Los Angeles were studied. Multiple electrophoresisin several experimental conditions were carried out,in addition to high performance liquid chromatography (HPLC) and molecular analysis to confirm thismutation. Four compound heterozygotes were observed:42 individuals heterozygous Hb AD Los Angeles, twowith Hb S/D Los Angeles disease, two individuals withHb D Los Angeles and beta-thalassemia and one withHb D Los Angeles and Hb Lepore. The heterozygoushemoglobin D Los Angeles is asymptomatic, even thoughits association with other variants and thalassemias maypresent varying degrees of clinical manifestations. Theresults presented emphasize the significance of theassociation of different laboratorial techniques for DLos Angeles diagnosis, and help to elucidate rarecombinations.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Adolescente , Adulto Joven , Persona de Mediana Edad , Recién Nacido , Preescolar , Niño , Técnicas de Laboratorio Clínico , Hemoglobinas
17.
J. bras. ginecol ; 106(5): 143-7, maio 1996. tab
Artículo en Portugués | LILACS | ID: lil-198242

RESUMEN

Para 1.301 adolescentes dos sexos masculinos e feminino foram distribuídos questionários relacionados às suas atividades sexuais. Dos resultados auferidos verificou-se ser mais precoce a iniciaçao sexual entre os masculinos. O tipo sexual mais frequente foi o vaginal, seguido do orovaginal. O adolescente masculino é mais poligâmico e entre eles é mais frequente o homossexualismo


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adolescente , Encuestas y Cuestionarios , Conducta Sexual
18.
Rev. bras. patol. clín ; 24(1): 6-9, jan.-mar. 1988. tab
Artículo en Portugués | LILACS | ID: lil-61005

RESUMEN

A sensibilidade de Streptococcus agalactiae frente a 13 antimicrobianos foi verificada pelo teste da difusäo em ágar. As amostras testadas foram sensíveis a ampicilina, cefalotina, cefoxitina, clindamicina, cloranfenicol, eritromicina, lincomicina, penicilina, rifampicina e vancomicina, apresentando sensibilidade variável para a tetra ciclina e resistência a canamicina e tobramicina. Foram também determinadas, para as estirpes, as concentraçöes mínimas inibitórias (CMIs) pelo teste da diluiçäo em ágar para 6 antimicrobianos. Para a ampicilina, cefalotina, clindamicina, lincomicina e penicilina, as CMI50 e CMI90 apresentaram valores similares aos encontrados para a CMI. Para a eritromicina, a CMI90 (0,12 microng/ml) foi duas vezes maior que a CMI50


Asunto(s)
Aminoglicósidos/farmacología , Ampicilina/farmacología , Técnicas Bacteriológicas , Cefoxitina/farmacología , Cefalotina/farmacología , Cloranfenicol/farmacología , Clindamicina/farmacología , Eritromicina/farmacología , Lincomicina/farmacología , Penicilinas/farmacología , Rifampin/farmacología , Streptococcus agalactiae/efectos de los fármacos , Tetraciclinas/farmacología , Tobramicina/farmacología , Vancomicina/farmacología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Microbiana , Serotipificación , Streptococcus agalactiae/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...