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1.
J Appl Microbiol ; 125(4): 1208-1215, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29920871

RESUMEN

AIMS: To improve RT-qPCR with an internal control and a synthetic standard curve to detect HEV in HIV co-infected patients. METHODS AND RESULTS: A single-stranded RNA (ssRNA) and a double-stranded DNA (dsDNA) synthetic curve were designed, compared to the international reference panel for HEV genotypes, and tested to quantify and detect a reference panel for HEV genotypes. The detection limit of the RNA synthetic curve (50 copies per ml) was better than the DNA synthetic curve (100 copies per ml) and the WHO standard curve (250 copies per ml). Then, 280 serum samples from HIV-positive patients were tested for HEV RNA, which was detected in 3·6% of serum samples. The viral load ranged from 2 × 102 copies per ml to 4·78 × 108 copies per ml. HEV IgM/IgG antibodies were not detected in the RNA-positive patients. Sequencing analysis of HEV showed that the virus belongs to genotype 3 (HEV GT3). CONCLUSIONS: Real-time PCR was a useful tool to estimate co-infection with HEV/HIV, even in patients with low viral loads and undetectable anti-HEV IgG and IgM antibodies. SIGNIFICANCE AND IMPACT OF THE STUDY: Hepatitis E virus genotype 3 (HEV GT3) has been associated with silent chronic hepatitis and cirrhosis in HIV-positive subjects worldwide, but there is a lack of data on this co-infection in Brazil.


Asunto(s)
Infecciones por VIH/sangre , Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/virología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Adulto , Brasil , Coinfección/sangre , Coinfección/virología , Femenino , Genotipo , Infecciones por VIH/virología , Hepatitis E/sangre , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/inmunología , Virus de la Hepatitis E/fisiología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Carga Viral
2.
Lett Appl Microbiol ; 66(4): 313-320, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29330866

RESUMEN

This study aimed to assess anthropogenic impact of surrounding population in the Private Reserve of Natural Heritage at Pantanal, the world's largest freshwater wetland ecosystem located in the centre of South America. Viral aetiological agents of acute gastroenteritis as rotavirus A (RVA), noroviruses, human adenoviruses, klassevirus and of hepatitis, as hepatitis A virus, were investigated in different aquatic matrices. Annual collection campaigns were carried out from 2009 to 2012, alternating dry and rainy seasons. Viral particles present in the samples were concentrated by the adsorption-elution method, with negatively charged membranes, and detected by qualitative and quantitative PCR. From a total of 43 samples at least one virus was detected in 65% (28) of them. Viruses were detected in all matrices with concentrations ranging from 2 × 102 to 8·3 × 104 genome copies per litre. A significant higher RVA frequency was observed in the dry season. Our data revealing dissemination of human enteric viruses in water matrices both inside and outside the reserve could be useful to trace faecal contamination in the environment and to minimize the risk of infection by exposure of susceptible individuals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is part of a collaborative project designed to investigate the environmental and health conditions of the Private Reserve of Natural Heritage at Pantanal, the largest seasonally flooded wetland in the world. The project aimed to promote health and quality of human and wildlife extending technical-scientific knowledge about pathogens present in the region. By assessing the occurrence of human enteric viruses in different water matrices we demonstrated the anthropogenic impact of surrounding population and pointed out the potential risk of infection by exposure of susceptible individuals.


Asunto(s)
Adenoviridae/aislamiento & purificación , Enterovirus/aislamiento & purificación , Gastroenteritis/virología , Virus de la Hepatitis A/aislamiento & purificación , Norovirus/aislamiento & purificación , Parques Recreativos , Rotavirus/aislamiento & purificación , Enfermedades Transmitidas por el Agua/virología , Adenoviridae/genética , Antígenos Virales , Brasil/epidemiología , Ecosistema , Enterovirus/genética , Heces/virología , Agua Dulce/virología , Gastroenteritis/epidemiología , Virus de la Hepatitis A/genética , Humanos , Norovirus/genética , Lluvia/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Rotavirus/genética , Estaciones del Año , Microbiología del Agua , Enfermedades Transmitidas por el Agua/epidemiología
3.
J Plant Physiol ; 221: 32-42, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29223880

RESUMEN

Plants developed receptors for solar UV-A/B radiation, which regulate a complex network of functions through the plant's life cycle. However, greenhouse grown crops, like tomato, are exposed to strongly reduced UV radiation, contrarily to their open-field counterparts. A new paradigm of modern horticulture is to supplement adequate levels of UV to greenhouse cultures, inducing a positive mild stress necessary to stimulate oxidative stress pathways and antioxidant mechanisms. Protected cultures of Solanum (cv MicroTom) were supplemented with moderate UV-A (1h and 4h) and UV-B (1min and 5min) doses during the flowering/fruiting period. After 30days, flowering/fruit ripening synchronization were enhanced, paralleled by the upregulation of blue/UV-A and UV-B receptors' genes cry1a and uvr8. UV-B caused moreover an increase in the expression of hy5, of HY5 repressor cop1 and of a repressor of COP1, uvr8. While all UV-A/B conditions increased SOD activity, increases of the generated H2O2, as well as lipid peroxidation and cell mebrane disruption, were minimal. However, the activity of antioxidant enzymes downstream from SOD (CAT, APX, GPX) was not significant. These results suggest that the major antioxidant pathways involve phenylpropanoid compounds, which also have an important role in UV screening. This hypothesis was confirmed by the increase of phenolic compounds and by the upregulation of chs and fls, coding for CHS and FLS enzymes involved in the phenylpropanoid synthesis. Overall, all doses of UV-A or UV-B were beneficial to flowering/fruiting but lower UV-A/B doses induced lower redox disorders and were more effective in the fruiting process/synchronization. Considering the benefits observed on flowering/fruiting, with minimal impacts in the vegetative part, we demonstrate that both UV-A/B could be used in protected tomato horticulture systems.


Asunto(s)
Antioxidantes/metabolismo , Estrés Oxidativo/efectos de la radiación , Solanum lycopersicum/efectos de la radiación , Rayos Ultravioleta , Redes y Vías Metabólicas
5.
Toxicol Lett ; 249: 29-41, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27021274

RESUMEN

Surface coating of silver nanoparticles may influence their toxicity, in a way yet to decipher. In this study, human keratinocytes (HaCaT cells) were exposed for 24 and 48h to well-characterized 30nm AgNPs coated either with citrate (Cit30 AgNPs) or with poly(ethylene glycol) (PEG30 AgNPs), and assessed for cell viability, reactive oxygen species (ROS), cytokine release, apoptosis and cell cycle dynamics. The results showed that Cit30 AgNPs and PEG30 AgNPs decreased cell proliferation and viability, the former being more cytotoxic. The coating molecules per se were not cytotoxic. Moreover, Ag(+) release and ROS production were similar for both AgNP types. Cit30 AgNPs clearly induced apoptotic death, while cells exposed to PEG30 AgNPs appeared to be at an earlier phase of apoptosis, supported by changes in BAX, BCL2 and CASP-3 expressions. Concerning the impact on cell cycle dynamics, both Cit30 and PEG30 AgNPs affected cell cycle regulation of HaCaT cells, but, again, citrate-coating induced more drastic effects, showing earlier downregulation of cyclin B1 gene and cellular arrest at the G2 phase. Overall, this study has shown that the surface coating of AgNPs influences their toxicity by differently regulating cell-cycle and cell death mechanisms.


Asunto(s)
Ácido Cítrico/farmacología , Queratinocitos/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Polietilenglicoles/farmacología , Plata/toxicidad , Anexina A5/análisis , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citocinas/metabolismo , Citometría de Flujo , Humanos , Especies Reactivas de Oxígeno/metabolismo
6.
Comput Methods Programs Biomed ; 109(3): 269-82, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23122302

RESUMEN

Cancer is the leading cause of death in economically developed countries and the second leading cause of death in developing countries. Malignant brain neoplasms are among the most devastating and incurable forms of cancer, and their treatment may be excessively complex and costly. Public health decision makers require significant amounts of analytical information to manage public treatment programs for these patients. Data mining, a technology that is used to produce analytically useful information, has been employed successfully with medical data. However, the large-scale adoption of this technique has been limited thus far because it is difficult to use, especially for non-expert users. One way to facilitate data mining by non-expert users is to automate the process. Our aim is to present an automated data mining system that allows public health decision makers to access analytical information regarding brain tumors. The emphasis in this study is the use of ontology in an automated data mining process. The non-experts who tried the system obtained useful information about the treatment of brain tumors. These results suggest that future work should be conducted in this area.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Minería de Datos/métodos , Algoritmos , Neoplasias Encefálicas/epidemiología , Simulación por Computador , Bases de Datos Factuales , Toma de Decisiones , Sistemas de Apoyo a Decisiones Clínicas , Humanos , Clasificación Internacional de Enfermedades , Salud Pública/métodos , Integración de Sistemas
7.
J Infect ; 47(2): 125-8, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12860145

RESUMEN

OBJECTIVE: HAV infection in patients with pre-existing chronic liver disease has been associated with increased rate of fulminant hepatitis and mortality. The aim of this study was to investigate the presence of serological and molecular HAV markers in a population of HCV infected patients. PATIENTS AND METHODS: The presence of total and IgM anti-HAV antibodies was investigated in 197 patients (mean age 44.8+/-12.5 years) referred to the Brazilian Reference Center for Viral Hepatitis and who tested positive for anti-HCV antibodies and HCV RNA. HAV RNA was investigated by reverse transcription-nested PCR in these patients.Results. One hundred seventy patients (86%) had total, but not IgM anti-HAV antibodies, being therefore, immune to hepatitis A, while 27 (14%) were not. A high proportion (6/27, 22%) of the susceptible patients presented markers of recent HAV infection: One patient was IgM anti-HAV positive, three were HAV RNA positive, and two presented both markers. By nucleotide sequencing, it was demonstrated that the HAV isolates infecting these patients belonged to subgenotypes 1A and 1B. CONCLUSIONS: Superinfection with HAV was a common event in the group of HCV infected patients under study. Implementation of hepatitis A vaccination should be considered for this population.


Asunto(s)
Hepatitis A/complicaciones , Hepatitis A/epidemiología , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Adulto , Brasil/epidemiología , Femenino , Hepatitis A/genética , Anticuerpos de Hepatitis A/sangre , Hepatitis C/genética , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Heart ; 89(4): 427-31, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12639873

RESUMEN

OBJECTIVE: To evaluate perioperative results and long term survival in patients with severe left ventricular (LV) dysfunction undergoing coronary artery bypass grafting (CABG) using non-cardioplegic methods. METHODS: From April 1990 through December 1999, 4100 consecutive patients underwent isolated CABG using hypothermic ventricular fibrillation. Of these, 141 (3.4%) had severe LV dysfunction (ejection fraction < 30%). Mean age was 58.3 (9.6) years. 64 patients (45.4%) were in Canadian Cardiovascular Society class III or IV and 16 (11.3%) were subjected to urgent or emergent surgery. A previous myocardial infarction was recorded in 127 (90.1%). The majority (89.4%) had triple vessel and 26 (18.4%) had left main disease. The mean number of grafts per patient was 3.1. At least one internal thoracic artery was used in all patients and 21 (14.8%) had bilateral internal thoracic artery grafts (1.2 arterial grafts per patient). RESULTS: Perioperative mortality was 2.8% (4 patients) and the incidence of acute myocardial infarction 2.8%. 50 (35.5%) patients required inotropes but only 16 (11.3%) required it for longer than 24 hours; 5 patients (3.5%) needed mechanical support. The incidence of renal failure was 3.5%. Mean duration of hospital stay was 9.6 (8.3) days. Follow up was 95% complete and extended for a mean of 57 (30) months. Late mortality was 11.5%. Actuarial survival rates at 1, 3, and 5 years were 96%, 91%, and 86%, respectively. CONCLUSIONS: Non-cardioplegic techniques are safe and effective in preserving the myocardium during CABG in patients with coronary artery disease and poor LV function, with low operative mortality and morbidity, and encouraging medium to long term survival rates.


Asunto(s)
Puente de Arteria Coronaria/métodos , Disfunción Ventricular Izquierda/cirugía , Implantación de Prótesis Vascular/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Estudios Prospectivos , Factores de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Disfunción Ventricular Izquierda/mortalidad
9.
Eur J Cardiothorac Surg ; 21(2): 181-6, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11825721

RESUMEN

OBJECTIVE: To demonstrate that staged, consecutive, carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG) are safe, perhaps preferable, alternative for the treatment of patients with severe carotid and coronary artery disease. METHODS: During an 8-year period ending December 1999, 77 (2.1%) of 3633 consecutive patients who were referred for isolated coronary surgery were found to have significant carotid disease and underwent CEA, and subsequently, CABG. The mean age was 65.2 +/- 5.9 years and 66 (85.7%) were males. The majority (84.4%) had triple vessel and 19.4% had left main disease. Carotid disease was unilateral in 71 patients (92.2%) and bilateral in six (7.8%), and 57 (74.0%) were neurologically asymptomatic. Only obstructions >70% were considered for endarterectomy. RESULTS: Eighty-three isolated CEAs were performed with direct clamping of the artery (mean 20.1 +/- 5.9 min) in all but one. There were no deaths. There were two strokes (2.4%) and three (3.6%) myocardial infarctions (MI). The mean admission time was 6.0 +/- 3.5 days. The staging interval was 32.4 days. During coronary surgery, a mean of 2.9 coronary grafts/patient was performed and all but one patient received at least one IMA graft. One patient (1.3%) died. There were two cases (2.6%) of MI and three patients (3.9%) had a stroke. Hence, the overall rates of perioperative mortality, MI and stroke were 1.3, 6.3 and 6.3%, respectively. The mean admission time was 8.3 +/- 6.0 days. CONCLUSIONS: Staging of carotid and coronary operations resulted in low global perioperative mortality and morbidity rates in these high-risk patients and is a good alternative therapeutic option.


Asunto(s)
Estenosis Carotídea/complicaciones , Estenosis Carotídea/cirugía , Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/cirugía , Endarterectomía Carotidea/métodos , Anciano , Estenosis Carotídea/mortalidad , Terapia Combinada , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Probabilidad , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Resultado del Tratamiento
10.
Boll Chim Farm ; 140(3): 160-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11486606

RESUMEN

The tetanus purified anatoxin is used in the preparation of the tetanus toxoid and multiple vaccines (dT, DT and DTP), all of them strictly following specifications established by the WHO with a minimum antigenic purity equal to 1,000 Lf/mgPN. Aiming to establish more sensitive and accurate methods for purification, samples from four different lots of tetanus anatoxin were submitted to gel filtration in twenty independent trials using the Sephacryl S-100 HR and S-200 HR resins. The Authors were careful to optimize their parameters of performance as to sample volume, elution and selectivity flow for tetanus anatoxin purification, allowing their use in industrial scale. The Sephacryl S-100 HR resin presented the best selectivity, that is, the best separation, allowing a greater linear-flow and, consequently, the best purity index. Satisfactory results were also achieved with the Sephacryl S-200 HR resin after optimization of chromatographic parameters for elution flow and volume of the sample applied. The good results of purification obtained, as well as the high chemical stability, have pointed out both the Sephacryl S-100 HR and S-200 HR resins as equally efficient for industrial production.


Asunto(s)
Toxoide Tetánico/aislamiento & purificación , Resinas Acrílicas , Cromatografía en Gel , Nitrógeno/química
11.
J Med Virol ; 63(4): 265-70, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11241456

RESUMEN

Eight cases of de novo hepatitis C virus (HCV) infection in a haemodialysis unit in Rio de Janeiro, Brazil, were retrospectively studied. HCV viraemia was demonstrated by RT nested PCR in seven of the seroconverters. Genotyping showed that six patients were infected with a genotype 1b strain and one with a genotype 1a strain. A phylogenetic analysis of nucleotide sequences of the HCV core region revealed that five of the six 1b isolates form a separate cluster when compared with other 38 HCV 1b core sequences randomly chosen from the GenBank. The revealed sequence similarities indicated the nosocomial spread of a single HCV strain within the unit. To investigate whether the patients infected with the same viral isolate display similar patterns of antibody response to individual proteins, serial serum samples were examined. A line immunoassay for qualitative and semi-quantitative determination of specific antibodies against recombinant and synthetic HCV antigens was employed. Despite infection with the same virus strain, the patients sera demonstrated different patterns of reactivity against individual structural and nonstructural HCV proteins immediately after seroconversion. For each patient, however, antibody responses remained mostly stable throughout the follow-up of 8 to 24 months.


Asunto(s)
Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/inmunología , Diálisis Renal , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Hepacivirus/aislamiento & purificación , Hepatitis C/sangre , Hepatitis C/virología , Humanos , Datos de Secuencia Molecular , Filogenia , Estudios Prospectivos , ARN Viral/análisis , Proteínas Recombinantes/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Ácido Nucleico , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunología , Proteínas no Estructurales Virales/inmunología , Proteínas Estructurales Virales/inmunología , Viremia
12.
Boll Chim Farm ; 138(7): 364-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10597658

RESUMEN

The tetanus purified anatoxin is used in the preparation of multiple immunoprophylactics. WHO (World Health Organization) specifies that the tetanus anatoxin must exhibit a degree of purity greater than or equal to 1,000 Lf/mg protein nitrogen (PN). Today liquid chromatography is a well established technique for the purification of tetanus anatoxin and several different methods are used in production scale. On a small scale, we purified tetanus anatoxin on Sephacryl S-200 High Resolution (gel filtration) and we obtained a successful high-yield purification. On the basis of these results, by combining conventional tangential flow filtration (TFF) at 50,000 N.M.W.L. (Nominal Molecular Weight Limit) ultrafiltration membrane with gel filtration on Sephacryl S-200 High Resolution, we have been able to purify 14 lots of tetanus anatoxin using the Bioprocess System (Amersham Pharmacia Biotech) to a large scale operation. Using this method, 77,401,332 doses of tetanus toxoid were prepared in 14 consecutive lots, supporting the reproducibility and reliability of the method presented here.


Asunto(s)
Toxina Tetánica/aislamiento & purificación , Resinas Acrílicas , Cromatografía por Intercambio Iónico , Industria Farmacéutica , Peso Molecular
13.
APMIS ; 107(11): 1020-2, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10598874

RESUMEN

Pseudohyphae formation by Candida albicans blastoconidia, as seen in vaginal smears, is a phenotypical change commonly assumed to mean fungal invasiveness, i.e. not mere colonization. C. albicans forms germ tubes in vitro in the presence of serum. In our search for inhibitory components of germ tube formation, we decided to study fibrinogen. The inhibition of germ tube formation by clinical isolates of C. albicans was evaluated in the presence of serial concentrations of fraction I, type IV and fraction I, type Is of fibrinogen from bovine plasma. Fibrinogen showed a dose-dependent, pH-independent inhibitory effect on the germ tube formation by C. albicans.


Asunto(s)
Candida albicans/efectos de los fármacos , Candida albicans/patogenicidad , Fibrinógeno/farmacología , Animales , Antifúngicos/administración & dosificación , Antifúngicos/farmacología , Sangre/microbiología , Candidiasis Vulvovaginal/inmunología , Candidiasis Vulvovaginal/microbiología , Bovinos , Relación Dosis-Respuesta a Droga , Femenino , Fibrinógeno/administración & dosificación , Fibrinógeno/inmunología , Humanos , Técnicas In Vitro , Fenotipo , Frotis Vaginal , Virulencia/efectos de los fármacos
14.
J Am Soc Nephrol ; 10(11): 2382-91, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10541298

RESUMEN

Although diabetic nephropathy is often a low renin state, the renin system appears to be implicated in its pathogenesis. In this study, it was hypothesized that the low plasma renin activity (PRA) is misleading, masking and perhaps reflecting an activated intrarenal renin system. PRA and renal vascular responses (inulin and para-aminohippurate clearance) to graded doses of an angiotensin II (AngII) antagonist, irbesartan, were assessed in eight healthy volunteers and 12 patients with type 2 diabetes mellitus and nephropathy on a 10 mmol Na intake, to activate the renin system. Basal PRA was suppressed in type 2 diabetes mellitus compared with the healthy subjects (0.58 +/- 0.14 versus 1.58 +/- 0.28 ng/L per s, mean +/- SEM; P < 0.01). Despite the low PRA, renal perfusion rose more in response to irbesartan in type 2 diabetes mellitus (714 +/- 83 to 931 +/- 116 ml/min; P = 0.002) than normal (624 +/- 29 to 772 +/- 49 ml/min; P = 0.008). The youngest patients were hyperfiltrating and showed the largest rise in renal plasma flow in response to irbesartan, whereas renal plasma flow rose less and GFR fell in patients with low basal GFR. PRA rose in response to irbesartan more gradually in the patients with type 2 diabetes mellitus, but ultimately matched the normal response. To account for the apparent paradox of a heightened renal hemodynamic response to an AngII antagonist in the face of a low PRA in type 2 diabetes mellitus, and the rise in PRA following the AngII antagonist, it is proposed that there is increased intrarenal AngII production in type 2 diabetes mellitus. This increase could account for suppressed circulating renin, the exaggerated renal vasodilator response to irbesartan, and the therapeutic effectiveness of interrupting the renin system in diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/fisiopatología , Renina/sangre , Adulto , Angiotensinógeno/biosíntesis , Compuestos de Bifenilo/farmacología , Presión Sanguínea , Índice de Masa Corporal , Nefropatías Diabéticas/sangre , Tasa de Filtración Glomerular , Humanos , Irbesartán , Persona de Mediana Edad , Circulación Renal , Tetrazoles/farmacología
15.
Am J Hypertens ; 12(4 Pt 1): 348-55, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10232494

RESUMEN

We have recently reported a combination of renal features that suggests independent angiotensin-mediated control of the renal circulation in the majority of hypertensive patients with type II diabetes. To ascertain whether other tissue elements of the renin-angiotensin-aldosterone system (RAAS) also were activated, we examined the adrenal response to angiotensin II (AngII) infusion on a low salt diet. We assessed also the renin response to the upright position in patients on a low salt diet and renin suppression in patients on a high salt diet. We compared responses in 42 hypertensive patients with type II diabetes (53.1 +/- 1.4 years, mean +/- SEM), 25 healthy controls (52.6 +/- 4.4 years); and 137 essential hypertensives without diabetes (43.3 +/- 1.2 years). A low renin state, defined as a plasma renin activity (PRA) <2.5 ng angiotensin I (AI)/mL/h after 5 to 7 days on a 10-mmol Na diet and 2 h of upright posture, was found in 21% of the essential hypertensives, but in only 14% of patients with type II diabetes. On this diet, PRA increased from 2.7 +/- 0.4 supine to 10.1 +/- 1.3 ng AI/mL/h upon standing in healthy subjects. In patients with type II diabetes, PRA was 3.6 +/- 0.4 and increased to 9.1 +/- 1.0 ng AI/mL/h. On a high salt (200 mmol) diet, healthy subjects showed the expected PRA suppression (0.3 +/- 0.1), but in patients with type II diabetes the PRA was less suppressed (1.2 +/- 0.3 ng AI/mL/h; P = .003). Thus, in most hypertensive patients with type II diabetes the RAAS shows normal activation, but is poorly suppressible. AngII infused intravenously to assess adrenal responsiveness in patients on a low salt diet caused an essentially identical increase in aldosterone concentration in patients with type II diabetes (21.1 +/- 1.7 to 44.0 +/- 5.9 ng/dL) and in essential hypertension (20.6 +/- 1.4 to 43.7 +/- 2.8 ng/ dL). The frequency of nonmodulation assessed as a blunted adrenal response to AngII infusion was identical in type II diabetes (47%) and in essential hypertension (46%) after exclusion of the low renin patients. Thus, at the level of one tissue renin system, the adrenal glomerulosa, responses were unaltered in patients with type II diabetes. The relative unresponsiveness of the renal blood supply to infused AngII in type II diabetes in association with an enhanced renal vasodilator response to angiotensin converting enzyme inhibition probably reflects local, intrarenal actions secondary to the diabetic state. The infrequency of a low renin state, and the inappropriately high renin levels on a high salt intake, provide a rational basis for pharmacologic interruption of the renin system to treat patients with type II diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Sistema Renina-Angiotensina/efectos de los fármacos , Adulto , Anciano , Aldosterona/sangre , Angiotensina II/farmacología , Diabetes Mellitus Tipo 2/complicaciones , Dieta Hiposódica , Femenino , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Postura , Renina/sangre , Renina/efectos de los fármacos , Vasoconstrictores/farmacología , Zona Glomerular/efectos de los fármacos
16.
J Med Virol ; 57(3): 259-63, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10022797

RESUMEN

A recent report has described the molecular cloning and characterization of a novel, single-stranded DNA virus, named TT virus (TTV), which was present in the sera of Japanese patients with posttransfusion hepatitis of unknown etiology [Okamoto et al. (1998) Hepatology Research 10:1-16]. Using a nested polymerase chain reaction assay, sera from Brazilian patients with acute non A-C hepatitis and blood donors were examined for the presence of TTV DNA sequences. Thirty-seven of 52 (71%) patients with acute non A-C hepatitis and 45 of 72 (62%) blood donors were found to have TTV sequences in their sera. Such a high proportion in blood donors indicated that TTV infection is common in the general Brazilian population. Partial nucleotide sequences (326 bases in open reading frame 1) from seven isolates were determined. By phylogenetic analysis, four TTV strains were classified into the genomic subgroup G1a described previously. The three others belonged to subgroup G1b. Sequence homologies between strains belonging to a same subgroup were 92.9-99.1%, whereas homologies of 85.9-90.2% were calculated between isolates from different subgroups.


Asunto(s)
Donantes de Sangre , Virus ADN , Hepatitis Viral Humana/epidemiología , Adolescente , Adulto , Anciano , Secuencia de Bases , Brasil/epidemiología , Niño , Virus ADN/clasificación , Virus ADN/genética , Virus ADN/aislamiento & purificación , ADN Viral , Femenino , Hepatitis Viral Humana/sangre , Hepatitis Viral Humana/virología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Prevalencia
17.
J Hepatol ; 29(3): 352-61, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9764980

RESUMEN

BACKGROUND/AIMS: A sequence of 40 amino acids within the nonstructural protein 5A of hepatitis C virus (HCV) has been suggested to be an interferon sensitivity determining region (ISDR). The variations in the ISDR after 12-14 years of chronic infection and the correlation between ISDR and interferon response were studied in patients who were infected by the same HCV isolate. METHODS: We determined the HCV-ISDRs of 13 chronically infected patients by direct sequencing of polymerase chain reaction products. All patients were infected by isolate HCV-AD78, but differed with respect to their sensitivity to interferon. Four patients were complete responders, two patients were non-responders, and seven showed a partial response. RESULTS: The ISDR of HCV-AD78 differed from a prototypical HCV-1b sequence in one amino acid and was therefore classified as an intermediate type. Direct sequencing of the HCV-ISDRs of the patients 12-14 years after infection, but before interferon therapy, revealed a rate of 2.2x10(-3) nucleotide substitutions per site per year, resulting in only single intermediate type amino acid exchanges. All sequences ranked with the intermediate type. Moreover, during interferon treatment no selection to a wild type ISDR was observed in five partial responders. CONCLUSIONS: Within the homogeneous patient group examined here, no correlation was found between the ISDR and the interferon response. Recent studies found only a small number of mutant type ISDRs in Europe. Additionally, our results indicate that the ISDR is a stable sequence element. This provides an explanation for the divergent data relating to the importance of the ISDR in different geographical regions.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Interferones/uso terapéutico , Proteínas no Estructurales Virales/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Secuencia de Bases , Femenino , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad
18.
Clin Diagn Virol ; 9(1): 1-7, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9562852

RESUMEN

BACKGROUND: The recently discovered hepatitis G virus (HGV) belongs, as hepatitis C virus (HCV), to the Flaviviridae family. HGV has been isolated from the serum of patients with non A-E hepatitis. However, the association of HGV with hepatitis is uncertain. OBJECTIVE: To determine the HGV prevalence in blood donors and in patients with liver disease and to evaluate a possible correlation between HGV infection and liver disease. STUDY DESIGN: Sera from a total of 113 consecutive patients with chronic liver disease were submitted to a series of liver enzymes and function tests and analyzed for the presence of HBsAg, anti-HBs, anti-HBc, anti-HCV, HCV RNA and HGV RNA. Prevalence of HGV RNA was determined in a group of 87 blood donors. RESULTS: Nine (10%) sera from blood donors and 15 (13%) sera from patients with chronic liver disease were HGV RNA positive. Some 28 (25%) patients were HCV RNA positive, with genotypes 1a, 1b and 3 present in 10, 12 and 5 patients, respectively. A total of 20 (18%) patients were HBsAg carriers. Five (4%) patients were double infected (one with HBV + HCV, one with HBV + HGV and three with HCV + HGV). CONCLUSION: The proportion (10%) of HGV-infected blood donors was very high when compared with other countries. The results did not allow to establish HGV as an etiologic agent for chronic liver disease. The parenteral route was the presumed means of HGV transmission for only one-third of the patients.


Asunto(s)
Donantes de Sangre , Flaviviridae/aislamiento & purificación , Hepatopatías/virología , Adulto , Anciano , Biomarcadores/sangre , Brasil/epidemiología , Enfermedad Crónica , Femenino , Flaviviridae/genética , Flaviviridae/inmunología , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Hepacivirus/aislamiento & purificación , Antígenos de Superficie de la Hepatitis B/inmunología , Anticuerpos contra la Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/aislamiento & purificación , Hepatitis Viral Humana/sangre , Hepatitis Viral Humana/epidemiología , Humanos , Hepatopatías/sangre , Hepatopatías/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , ARN Viral
19.
J Gen Virol ; 79 ( Pt 12): 3085-9, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9880026

RESUMEN

Recently a new human virus, TT virus (TTV) was identified in the serum of a patient with post-transfusion hepatitis of unknown aetiology. Comparative sequence analysis of a 222 nt fragment of ORF 1 of TTV was performed to assess the genomic variability of this virus. Phylogenetic analysis of the nucleotide sequences of 76 TTV isolates collected in 17 countries segregated them into two major groups: TTV 1 and TTV 2. The TTV 1 group comprised two distinct subgroups, which corresponded to previously described TTV subtypes 1a and 1b. The TTV 2 group was separated into four main branches, two of which included sequences previously provisionally attributed as TTV types 2 and 3. Bootstrap resampling, however, did not support the reliability of this grouping, suggesting that the isolates in the TTV 2 group should be considered as subtypes of a single type rather than different TTV types.


Asunto(s)
Virus ADN/genética , Hepatitis/virología , Secuencia de Bases , Virus ADN/clasificación , ADN Viral , Variación Genética , Hepatitis/sangre , Hepatitis/clasificación , Humanos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Análisis de Secuencia de ADN
20.
Rev Port Cardiol ; 17(12): 967-73, 1998 Dec.
Artículo en Portugués | MEDLINE | ID: mdl-9973857

RESUMEN

At present, the treatment for acute myocardial infarction is revascularization during the critical initial period of six hours after the beginning of coronary occlusion. Despite the fact that surgery performed within this time period presents a hospital of mortality around 2%, and with excellent results in the long term, it is seldom used due to logistic limitations and capabilities of hospital infrastructures, high costs and the possibility of the surgical team initiating surgery inside the useful time period. Surgery is thus limited to the patients with suitable anatomy, who are not candidates or had failure of thrombolytic/angioplasty therapy and are in the six-hour period after initiation of symptoms. Surgery performed at a later stage has good results if performed in a non emergency situation, specially after the first 72 hours. Surgery continues to be the only treatment for the mechanical complications of infarction, and good results have recently been shown in ventricular septal ruptures, with hospital mortality of 14%, due to the use of an endoventricular patch in patients operated early, before the consequences of low cardiac output develop at systemic level. In the surgical treatment of mitral regurgitation, the tendency has been to use repair techniques whenever possible, but still with hospital mortality up to 15%. The recent advances of the techniques and tactics of myocardial preservation during surgery have made a very significant contribution to the better results we see today.


Asunto(s)
Infarto del Miocardio/cirugía , Puente de Arteria Coronaria , Rotura Cardíaca Posinfarto/etiología , Rotura Cardíaca Posinfarto/cirugía , Humanos , Insuficiencia de la Válvula Mitral/etiología , Insuficiencia de la Válvula Mitral/cirugía , Infarto del Miocardio/complicaciones , Factores de Riesgo , Factores de Tiempo
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