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2.
J Parasitol ; 106(2): 295-307, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32316032

RESUMO

Cyclospora cayetanensis is a coccidian parasite of humans of known and growing importance. However, we are surprisingly naïve as to our understanding of how to diagnose it and how it develops inside the human body. Here we provide details of the developmental stages of C. cayetanensis in the gallbladder of a 33-yr-old male with human immunodeficiency virus. The gallbladder was removed surgically in 2001 because of severe abdominal pain. For the present study, the archived paraffin block of gallbladder was processed for light microscopy and transmission electron microscopy (TEM). Histological sections were examined after staining with hematoxylin and eosin (HE) or using the periodic acid Schiff (PAS) reaction. Immature and mature asexual stages, gamonts, and oocysts were seen in epithelial cells, both in the superficial epithelium and in glands. The merozoites were present singly, in pairs, and 3 or more in a single parasitophorous vacuole in the host cytoplasm. Up to 6 nuclei were seen in immature schizonts without evidence of merozoite formation. Mature schizonts were 7.6 × 5.1 µm and contained up to 10, 3-4 µm long merozoites. Merozoites were 0.6 to 2.0 µm wide, and their shape varied from pear-shaped to slender. Merozoites were generally PAS-positive; however, some were intensely positive, some had only minute granules, while others were PAS-negative. The microgamonts (male) were 6.6 × 5.2 µm and contained fewer than 20 microgametes around a residual body. The microgametes were up to 2 µm long and were flagellated. Macrogamonts (female) contained distinctive eosinophilic wall-forming bodies that varied in size and were less than 1 µm in HE-stained sections. Macrogamonts were 5.8-6.5 × 5.3-6.5 µm. Oocysts in sections were unsporulated and had a diameter of 5.7-7.5 µm. The TEM examination confirmed the histologic findings. The DNA extracted from paraffin sections was confirmed as C. cayetanensis with real-time PCR. The detailed description of the life cycle stages of C. cayetanensis reported here in an immunosuppressed patient could facilitate histopathologic diagnosis of this parasite. We have shown that the parasite's development more closely resembles that of Cystoisospora than Eimeria and that the parasite has multiple nuclei per immature meront indicating schizogony, and we have undermined evidence for a Type II meront.


Assuntos
Cyclospora/crescimento & desenvolvimento , Ciclosporíase/parasitologia , Vesícula Biliar/parasitologia , Infecções por HIV/complicações , Adulto , Cyclospora/genética , Cyclospora/ultraestrutura , Ciclosporíase/imunologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Feminino , Vesícula Biliar/patologia , Vesícula Biliar/ultraestrutura , Humanos , Hospedeiro Imunocomprometido , Estágios do Ciclo de Vida , Masculino , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase em Tempo Real
3.
J Nutr Health Aging ; 24(1): 113-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31886817

RESUMO

AIM: To evaluate the ability of the Short Physical Performance Battery (SPPB) for predicting 1-year adverse outcomes of acutely ill older outpatients. METHODS: Prospective study with 512 acutely ill older outpatients (79.4±8.3 years, 63% female) in an acute care day hospital. The SPPB was administered at admission. Participants were classified as low (0-4 points), intermediate (5-8 points), or high (9-12 points) performance. Primary outcomes were new dependence in basic activities of daily living (ADL), hospitalization, and death at 1 year. Cox models tested whether the SPPB predicted outcomes after adjustment for sociodemographic factors, comorbidities and well-known geriatric conditions. We also estimated whether the chair-stand and balance tests improve the SPPB's ability to identify patients at high risk of adverse outcomes. RESULTS: Patients with intermediate or low SPPB performance were at higher risk of 1-year new ADL dependence (32% vs 13%: adjusted hazard ratio [aHR]=2.00; 95%CI=1.18-3.37; 58% vs 13%: aHR=3.40; 95%CI=2.00-5.85, respectively), hospitalization (43% vs 29%: aHR=1.56; 95%CI=1.04-2.33; 44% vs 29%: aHR=1.80; 95%CI=1.15-2.82), and death (18% vs 6%: aHR=2.54; 95%CI=1.17-5.53; 21% vs 6%: aHR=2.70; 95%CI=1.17-6.21). Use of all three components (versus gait speed alone) improved predictions of new ADL dependence (Harrell's C=0.73 vs 0.70;P=0.01), hospitalization (Harrell's C=0.60 vs 0.57;P=0.04), and death (Harrell's C=0.67 vs 0.62;P=0.04). CONCLUSIONS: The SPPB is as a powerful tool for identifying acutely ill older outpatients at high-risk of adverse outcomes. The combination of the three components of the SPPB resulted in better predictive performance than gait speed alone.


Assuntos
Avaliação Geriátrica/métodos , Força Muscular/fisiologia , Desempenho Físico Funcional , Equilíbrio Postural/fisiologia , Velocidade de Caminhada/fisiologia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Hospitalização , Humanos , Masculino , Pacientes Ambulatoriais , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
4.
Sci Total Environ ; 648: 398-407, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121039

RESUMO

This paper is focused on the hydrogeochemical characterization of the Negro River along its course, as well as in the proposal of a functioning model for the contamination processes in order to establish potential cause-effect relationships between water quality, geology (ARD), mining activities (AMD) and the tectonic framework as transmission vector of acidity, metals and sulphates. The scenario shows a heavily-contaminated river compared to the unaffected regional background. By graphical and statistical treatments of physico-chemical data of Negro River and the unaffected values of regional background and other AMD/ARD representative rivers' it is possible to conclude that Antamina Mine, is not the cause of the Negro River contamination, without the need of isotopic tracers, but just through the inexistent concentrations of Cu, Bi and Mo found in the waters. In the proposed contamination model, climatic factors (glacial retreat) activate geological (ARD) processes. The tectonic scenario (faults) intervenes as a transport medium of the contamination flux from the sulphide oxidation surface in upper altitudes until the spring in lower altitudes. At the end, it is concluded that this contamination comes from the recent glacial retreat in areas near the Cordillera Blanca that has left massive amounts of sulphide materials exposed to weathering conditions, oxidizing naturally (ARD processes) and finally contributing to the contamination of the Negro River through faults. In this case, we would face an ARD process in the strict sense, which is the direct oxidation of sulphides outcropping in the upper part of the mountain with the generation of sulphates, the release of hydrogen ions and the consequent generation of acid and the dissolution of the metals. This ARD process would come from the glacial retreat, which, through the faults, transports contaminated water until the spring.

5.
Chemosphere ; 211: 736-744, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30099158

RESUMO

Aljustrel mining area (South Portugal) belongs to the Iberian Pyrite Belt (IPB). It is classified of high environmental risk due to its large tailings and to the Acid Mine Drainage (AMD) affected waters, generated by sulphides' oxidation. Integrating biological parameters (for the first time) in the input data matrix of the software PreFuRGe, allowed a better discrimination of the diatoms' responses to the stimuli caused by the hydrochemical changes imposed by the processes affecting water quality. Each hydrochemical scenario, was modeled by imposing maximum and minimum limits for each antecedent, according to the conditions imposed by the consequent, which in this case were the number of diatom species and pH. Thus, PreFuRGe evidenced some qualitative aspects that could not be achieved by classic statistics. pH appeared as the main discriminator of diversity and diatom species composition, nevertheless and due to the complex environment under study other chemical interactions must be considered: (a) AMD waters, with extremely low pH values, but also with extremely high hydrogeochemical complexity, represented by a mixture of metals, do not allow to associate, unequivocally, the reduction in diatom diversity to pH, but also to high metal (loid)s concentrations; (b) in the most alkaline waters, with higher abundance of diatom species, average to high concentrations of Na and Cl (due to Cenozoic sediments) do not seem to affect diatom diversity. This methodology proved to be an efficient tool to establish, for the first time, cause-effect relationships, improving the comprehension between biological (diatoms) and hydrochemical parameters.


Assuntos
Monitoramento Ambiental/métodos , Lógica Fuzzy , Mineração/métodos , Poluentes Químicos da Água/química , Portugal , Poluentes Químicos da Água/análise
7.
Cytopathology ; 24(2): 81-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21999617

RESUMO

BACKGROUND: Follicular lesion of undetermined significance (FLUS) was introduced for fine needle aspiration (FNA) cytology in which there is insufficient evidence to classify the lesion as follicular neoplasm/suspicious of follicular neoplasm or suspicious for malignancy. The recommended management was repeat FNA and correlation with clinical and radiological data. In 2009 we started a joint clinicopathological protocol to improve management of FLUS, recommending follow-up with repeat FNA at 6months. The aim of this study was to report on the audit of results of this protocol. METHODS: We reviewed the medical records of the patients with FLUS at a single hospital. Between 2007 and 2010 we found 135 cases with this diagnosis (3.6%). We only had long enough follow-up information for the 95 patients that were included in the present study. RESULTS: FLUS was diagnosed in 74 FNAs before protocol implementation (3.2%) and 61 FNAs after (4.2%), with follow-up of 46 and 49 patients, respectively. Before 2009, 38/46 (82.6%) patients had surgical excisions, compared with 32/49 (65.3%): a significant reduction of 17% in the number requiring surgery (P=0.05). We have also shown a reduction in the median time to surgery (11.9 versus 2.9 months). Despite the joint protocol, the FNA was only repeated in two patients. The histological diagnoses were similar in the two periods of time: 31.6% and 31.3% follicular adenomas; 13.1% and 3.1% (P=0.2) papillary carcinoma (follicular variant). CONCLUSIONS: Implementation of a joint protocol reduced the number of surgical operations in patients with FLUS but in most cases FNA was not repeated as recommended. Excision was justified in one-third of operated patients. Less than 15% of lesions were malignant, which is in accordance with previous reports in the literature.


Assuntos
Adenocarcinoma Folicular/diagnóstico , Carcinoma/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/diagnóstico , Adenocarcinoma Folicular/patologia , Biópsia por Agulha Fina , Carcinoma/patologia , Carcinoma Papilar , Citodiagnóstico , Humanos , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia
8.
Environ Int ; 44: 18-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22387227

RESUMO

Exposure to air pollution has been related with the most varied adverse health outcomes. This study aims to assess the impact of air pollution on the emergency hospitalization for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part I aims to: i) evaluate the concentrations of PM(10), SO(2) and CO at two sites in Rio de Janeiro and compare them; ii) analyse the concentrations observed according to the national and international standards; and iii) analyse the air pollutants behaviour, namely, annually, seasonally, daily and considering weekdays/weekends variations. The pollutant concentrations were measured at two different sites in Rio de Janeiro and the analysis was performed for the period between September 2000 and December 2005. Results showed that PM(10) concentrations in Rio de Janeiro exceeded the daily and annual standards imposed by the European Union, the Brazilian legislation and WHO guidelines. Regarding SO(2) and CO, concentrations were, generally, below both European and Brazilian standards. Nevertheless, considering WHO guidelines, SO(2) threshold for daily concentrations (20 µg m(-3)) was exceeded around 150 times. Behaviour assessment showed that the influence of traffic is a major factor affecting the air pollution in Rio de Janeiro. Considering the results achieved and the proven health effects of air pollution, strategies should be defined for its reduction, particularly concerning particulate matter, and consequently contribute to the protection of public health.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Brasil , Monóxido de Carbono/análise , Humanos , Morbidade , Material Particulado/análise , Doenças Respiratórias/induzido quimicamente , Dióxido de Enxofre/análise
9.
Environ Int ; 43: 1-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22446713

RESUMO

The effects of air pollution on health have been studied worldwide. Given that air pollution triggers oxidative stress and inflammation, it is plausible that high levels of air pollutants cause higher number of hospitalisations. This study aimed to assess the impact of air pollution on the emergency hospitalisation for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part II aimed to estimate the association between the concentrations of PM10, SO2 and CO observed in Rio de Janeiro and the number of emergency hospitalisations at a central hospital due to respiratory diseases. The pollutant concentrations were measured at two different sites in Rio de Janeiro, but the excess relative risks were calculated based on the concentrations observed at one of the sites, where limits were generally exceeded more frequently, between September 2000 and December 2005. A time series analysis was performed using the number of hospitalisations, divided in three categories (children until 1 year old, children aged between 1 and 5 years old and elderly with 65 years old or more) as independent variable, the concentrations of pollutants as dependent variables and temperature, relative humidity, long term trend, and seasonality as confounders. Data were analysed using generalised additive models with smoothing for some of the dependent variables. Results showed an excess risk of hospitalisation for respiratory disease higher than 2% per 10 µg m⁻³ increase in PM10 concentrations for children under 5 years old, of 2% per 10 µg m⁻³ increase in SO2 for elderly above 65 years old and around 0.1% per 10 µg m⁻³ increase in CO for children under 1 year and elderly. Other studies have found associations that are in agreement with the results achieved in this study. The study suggests that the ambient levels of air pollutants experienced in Rio de Janeiro between 2000 and 2005 were linked to the number of hospitalisations for respiratory diseases among children and elderly.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Brasil , Monóxido de Carbono/análise , Pré-Escolar , Exposição Ambiental/análise , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Morbidade , Material Particulado/análise , Medição de Risco , Dióxido de Enxofre/análise
11.
Clin Transl Oncol ; 11(1): 54-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19155205

RESUMO

INTRODUCTION: To evaluate the sequential administration of doxorubicin (A) and cyclophosphamide (C) followed by weekly docetaxel in women with stage II to IIIA breast cancer. PATIENTS AND METHODS: Patients received 60 mg/m(2) of A and 600 mg/m(2) of C every three weeks for four cycles followed by 12 infusions of weekly docetaxel at a dose of 36 mg/m(2) and with a 2-week resting period. RESULTS: Sixty-three women were included. On an intention-to- treat basis, clinical response rate was 90% (95% CI: 83-98), with 46% complete responses. Breast-conserving surgery could be performed in 43 patients (68%). Complete pathological responses in the breast were confirmed in 17% of patients. No correlations between levels of expression of topoisomerase II alpha, survivin or p27 and the pathological response were detected. The study treatment was generally well tolerated. CONCLUSION: Neoadjuvant AC followed by weekly docetaxel is a feasible regimen for patients with early-stage breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/biossíntese , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , DNA Topoisomerases Tipo II/biossíntese , Proteínas de Ligação a DNA/biossíntese , Docetaxel , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/biossíntese , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Antígeno Nuclear de Célula em Proliferação/biossíntese , Survivina , Taxoides/administração & dosagem , Taxoides/efeitos adversos
12.
Clin. transl. oncol. (Print) ; 11(1): 54-59, ene. 2009.
Artigo em Inglês | IBECS | ID: ibc-123576

RESUMO

INTRODUCTION: To evaluate the sequential administration of doxorubicin (A) and cyclophosphamide (C) followed by weekly docetaxel in women with stage II to IIIA breast cancer. PATIENTS AND METHODS: Patients received 60 mg/m(2) of A and 600 mg/m(2) of C every three weeks for four cycles followed by 12 infusions of weekly docetaxel at a dose of 36 mg/m(2) and with a 2-week resting period. RESULTS: Sixty-three women were included. On an intention-to- treat basis, clinical response rate was 90% (95% CI: 83-98), with 46% complete responses. Breast-conserving surgery could be performed in 43 patients (68%). Complete pathological responses in the breast were confirmed in 17% of patients. No correlations between levels of expression of topoisomerase II alpha, survivin or p27 and the pathological response were detected. The study treatment was generally well tolerated. CONCLUSION: Neoadjuvant AC followed by weekly docetaxel is a feasible regimen for patients with early-stage breast cancer (AU)


No disponible


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase II como Assunto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante/métodos , DNA Topoisomerases Tipo II/biossíntese , Antígenos de Neoplasias/biossíntese , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Imuno-Histoquímica , Proteínas Associadas aos Microtúbulos/biossíntese
13.
Diagn Cytopathol ; 29(5): 280-2, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14595796

RESUMO

Liver involvement by multiple myeloma as space-occupying lesions is a rare condition with only a few cases reported in the literature. We present a case of a 68-year-old man with a prostatic adenocarcinoma who developed a multiple myeloma as a second primary malignancy. Hepatic nodules were discovered in the tomographic study. Fine-needle aspiration of one of the hepatic lesions showed a pleomorphic plasmacytoid tumor. Immunocytochemistry using p63 and kappa-chain antibodies was useful in determining the plasmacytic nature of the cells.


Assuntos
Adenocarcinoma/patologia , Neoplasias Hepáticas/patologia , Segunda Neoplasia Primária/patologia , Plasmocitoma/patologia , Neoplasias da Próstata/patologia , Idoso , Biópsia por Agulha Fina , Diagnóstico Diferencial , Humanos , Cadeias kappa de Imunoglobulina/metabolismo , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Segunda Neoplasia Primária/metabolismo
14.
Clin Exp Dermatol ; 27(2): 132-4, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11952706

RESUMO

Classically, recall dermatitis refers to chemotherapy-induced reactivation of skin damage caused by radiotherapy months, or even years, earlier. The concept of recall dermatitis has now been extended to include radiation recall dermatitis induced by other drugs, ultraviolet radiation, extravasation of drugs, and allergic contact dermatitis. We now describe recall dermatitis along the residual cutaneous lesions of a previous thoracic herpes zoster in a patient who developed a drug eruption after oral administration of aciclovir. The most striking feature consisted of confluent linear erythema along the dermatomes previously involved by the herpes zoster episode. Histopathologic study demonstrated small foci of spongiosis, vacuolar changes involving the basal layer of the epidermis and single necrotic keratinocytes scattered within the epidermis. The papillary dermis appeared oedematous and with dilated blood capillaries surrounded by a sparse inflammatory infiltrate composed mainly of lymphocytes. Serial sections failed to demonstrate cytologic changes of herpes varicella zoster infection. We interpreted this case as an example of recall dermatitis because the widespread cutaneous eruption secondary to aciclovir was more intense in skin previously compromised by herpes varicella zoster infection. To the best of our knowledge, recall dermatitis has not been described before at the site of previous involvement by herpes zoster.


Assuntos
Aciclovir/efeitos adversos , Antivirais/efeitos adversos , Toxidermias/etiologia , Herpes Zoster/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade
15.
Circulation ; 104(15): 1822-30, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11591621

RESUMO

BACKGROUND: We recently obtained evidence demonstrating that cultured bovine endothelial cells contain cytosolic proteins that form complexes with the 3'-untranslated region of endothelial nitric oxide synthase (eNOS) mRNA and are associated with its destabilization. The aim of this study was to determine the presence of such proteins and eNOS expression in hypercholesterolemic rabbits as an in vivo model of endothelial dysfunction. METHODS AND RESULTS: Endothelium-dependent relaxation to acetylcholine and the calcium ionophore A23187 was reduced in aortic segments from hypercholesterolemic rabbits compared with controls. Treatment of hypercholesterolemic rabbits with cerivastatin (0.1 mg. kg body wt(-1). d(-1)) restored endothelium-dependent relaxation. Aortic eNOS expression was reduced in hypercholesterolemic rabbits and was accompanied by enhanced binding activity of a 60-kDa cytosolic protein and reduced stability of eNOS mRNA. Cerivastatin treatment upregulated eNOS expression and reduced the interaction of the cytosolic protein with the 3'-untranslated region of eNOS mRNA. Mononuclear cells from hypercholesterolemic rabbits also showed a marked reduction of eNOS expression and eNOS mRNA stability and an increase in binding activity of the cytosolic protein, which were also prevented by cerivastatin treatment. CONCLUSIONS: These results demonstrate the presence of a 60-kDa protein that binds to eNOS mRNA and reductions in eNOS expression in both vascular wall and mononuclear cells that are prevented by cerivastatin.


Assuntos
Regulação da Expressão Gênica , Hipercolesterolemia/fisiopatologia , Leucócitos Mononucleares/enzimologia , Óxido Nítrico Sintase/metabolismo , Piridinas/farmacologia , Regiões 3' não Traduzidas/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Citosol/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/tratamento farmacológico , Técnicas In Vitro , Ionóforos/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Substâncias Macromoleculares , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo III , Ligação Proteica/efeitos dos fármacos , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , Coelhos , Especificidade por Substrato , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
16.
Rev Esp Cardiol ; 54(7): 880-6, 2001 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-11446964

RESUMO

BACKGROUND: Although different studies have evaluated the ability of endothelial cells to produce NO in the setting of the endothelial dysfunction associated with hypertension, less it is known about the soluble guanylate cyclase system. AIM: To analyze the level of expression of sGC in the vascular wall in Stroke-prone spontaneously hypertensive rats (SHRSP). Moreover, the effect of treatment with an alpha1 adrenergic antagonist, doxazosin, on sGC expression was also evaluated. METHODS: The study was performed in 24 untreated 20-week-old SPSHR and 12 SPSHR treated orally with doxazosin (10 mg/Kg bw/day; for 15 days). A group of normotensive Wistar-Kyoto (WKY) rats were used as controls (n = 12). RESULTS: Isolated aortic segments from SHRSP showed impaired response to SNP. Doxazosin treatment prevented impaired vasodilatory response to SNP. Expression of the beta1 sGC in the vascular wall of SHRSP determined by Western blot and immunohistochemistry was markedly reduced with respect to that of WKY. Doxazosin treatment increased of beta1 sGC expression in treated SHRSP particularly at the medium level with respect to that of untreated SHRSP. CONCLUSION: SHRSP showed reduced expression of beta1 sGC in the vascular wall and an impaired vasodilator response to SNP which improved with doxazosin treatment. These results suggest the role the sGC system may play in the global treatment of endothelial dysfunction.


Assuntos
Anti-Hipertensivos/uso terapêutico , Modelos Animais de Doenças , Doxazossina/uso terapêutico , Guanilato Ciclase/biossíntese , Hipertensão/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Masculino , Nitroprussiato/farmacologia , Ratos , Ratos Endogâmicos SHR , Vasodilatadores/farmacologia
17.
Hypertension ; 37(4): 1171-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11304520

RESUMO

The mechanisms by which persistent proteinuria induces interstitial inflammation and fibrosis are not well known, although nuclear factor-kappaB (NF-kappaB), which regulates the transcription of many genes involved in renal injury, could be implicated. In rats with intense proteinuria, we studied the renal activation of NF-kappaB as well as the potential involvement of the vasoactive hormones angiotensin II (Ang II) and endothelin-1 (ET-1). Uninephrectomized Wistar-Kyoto rats receiving 1 g/d of BSA had proteinuria but no renal morphological lesions at day 1. By contrast, tubular atrophy and/or dilation and mononuclear cell infiltration were observed after 8 or 28 days of BSA administration, coinciding with maximal proteinuria. In relation to control uninephrectomized rats, the renal cortex of nephritic rats showed an increment in the activation of NF-kappaB at all time periods studied. By in situ Southwestern histochemistry, NF-kappaB activity was mainly localized in proximal tubules, interstitial mononuclear cells, and, to a lesser extent, the glomeruli. The administration of the ACE inhibitor quinapril plus the ET(A)/ET(B) receptor antagonist bosentan during 28 days to BSA-overloaded animals diminished proteinuria, renal lesions, and NF-kappaB activity more markedly than single drugs. Cultured tubular epithelial cells exposed to BSA revealed an intense NF-kappaB activation in a time- and dose-dependent manner. Incubation of cells with receptor antagonists of Ang II (AT(1): losartan and AT(2): PD-123,319) or ET-1 (ET(A): BQ123 and ET(B): IRL1038) inhibited significantly the BSA-induced NF-kappaB activity (90%, 75%, 90%, and 60% of inhibition versus basal, respectively). Our results show that overload proteinuria causes NF-kappaB activation in tubular epithelial cells both in vivo and in vitro. The vasoactive peptides Ang II and ET-1 appear to be implicated in this effect. The results reveal a novel mechanism of perpetuation of renal damage induced by persistent proteinuria.


Assuntos
Endotelina-1/metabolismo , Túbulos Renais/metabolismo , NF-kappa B/metabolismo , Nefrite/patologia , Nefrite/urina , Proteinúria/metabolismo , Análise de Variância , Angiotensina II/antagonistas & inibidores , Angiotensina II/metabolismo , Animais , Atrofia , Linhagem Celular , Células Epiteliais/metabolismo , Feminino , Córtex Renal/metabolismo , Córtex Renal/patologia , Túbulos Renais/patologia , Nefrectomia , Ratos , Ratos Endogâmicos WKY
18.
Surgery ; 129(3): 255-66, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231453

RESUMO

BACKGROUND: The current study evaluated whether biliary tract obstruction stimulates inducible nitric oxide synthase (iNOS) protein expression in the liver and analyzed the implication of lymphomononuclear cells and interleukin-4 (IL-4). METHODS: Male Wistar rats were used. Bile flow interruption was achieved by a complete division of the extrapancreatic common bile duct. iNOS expression was determined by both the Western blot technique and immunohistochemistry. RESULTS: iNOS protein was markedly expressed in the liver 7 days after bile duct obstruction. Treatment with thymostimulin (TP-1), a partially purified thymic extract, reduced the intensity of the expression of iNOS protein in the liver after bile duct ligation. Recent data have suggested that IL-4 attenuates iNOS protein expression. We then analyzed the involvement of this anti-inflammatory cytokine on the modulation of iNOS expression in the liver. The liver from rats that underwent bile duct ligation (BDL) showed a lower content of IL-4 than that of sham-operated (SO) rats. TP-1 treatment increased the content of IL-4 in the liver. Liver slices incubated in vitro with Escherichia coli lipopolysaccharide (LPS, 10 microg/mL) stimulated the expression of iNOS protein. The level of LPS-induced iNOS expression was reduced by lymphomononuclear cells obtained from sham-operated animals. However, lymphomononuclear cells isolated from BDL rats potentiated the induction of iNOS expression by LPS-stimulated liver. However, lymphomononuclear cells from TP-1-treated BDL rats failed to modify LPS-stimulated iNOS expression. The different effect of lymphomononuclear cells on the modulation of iNOS expression in the liver was associated with their ability to generate IL-4. CONCLUSIONS: The liver of jaundiced rats markedly expressed iNOS protein, which was associated to modifications in the content of IL-4 in the liver. Furthermore, lymphomononuclear cells modulate iNOS protein expression in the liver by a mechanism in which IL-4 is involved.


Assuntos
Colestase/enzimologia , Leucócitos Mononucleares/fisiologia , Fígado/enzimologia , Óxido Nítrico Sintase/metabolismo , Animais , Ductos Biliares , Interleucina-4/metabolismo , Ligadura , Fígado/metabolismo , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Wistar , Extratos do Timo/farmacologia
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