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1.
Genes Immun ; 13(2): 197-201, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21866115

RESUMEN

Non-Hodgkin lymphoma (NHL) has been associated with immunological defects, chronic inflammatory and autoimmune conditions. Given the link between immune dysfunction and NHL, genetic variants in toll-like receptors (TLRs) have been regarded as potential predictive factors of susceptibility to NHL. Adequate anti-tumoral responses are known to depend on TLR9 function, such that the use of its synthetic ligand is being targeted as a therapeutic strategy. We investigated the association between the functional rs5743836 polymorphism in the TLR9 promoter and risk for B-cell NHL and its major subtypes in three independent case-control association studies from Portugal (1160 controls, 797 patients), Italy (468 controls, 494 patients) and the US (972 controls, 868 patients). We found that the rs5743836 polymorphism was significantly overtransmitted in both Portuguese (odds ratio (OR), 1.85; P=7.3E-9) and Italian (OR, 1.84; P=6.0E-5) and not in the US cohort of NHL patients. Moreover, the increased transcriptional activity of TLR9 in mononuclear cells from patients harboring rs5743836 further supports a functional effect of this polymorphism on NHL susceptibility in a population-dependent manner.


Asunto(s)
Linfoma no Hodgkin/genética , Polimorfismo Genético , Receptor Toll-Like 9/genética , Femenino , Genética de Población , Humanos , Linfoma no Hodgkin/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo
2.
Environ Res ; 110(5): 424-7, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20307876

RESUMEN

Chromated copper arsenate (CCA) was widespread used as a chemical wood preservative with application in the construction of playground equipment, fences, jetties, and naval. Environmental protection agency (EPA) had limited the use of CCA-treated wood on 2002, due to probable implications on both human and environmental health. Although this fact, several industries pursue the use of this product within their manufactories. In addition, the durability of this wood for 60 years, makes these treated products an hazard to the public health. In the present work, studies were explored exposing mice to CCA, during 14, 24, 48, and 96 h for the assessment of acute toxicity of CCA. Kidney and liver were removed, prepared for histology and for metalloid, and copper content evaluation by high resolution inductively coupled plasma mass spectroscopy. The histological results evidenced apparently normal structures for control animals and group exposed to As2O5. On the contrary, the renal sections of the animals treated with CCA revealed epithelium cells desquamation, hyaline, and granular casts in renal tubules lumen. Furthermore, high levels of arsenic were detected in the kidney of animals treated with CCA over 14 and 48 h, being significantly greater than controls. Although this approach underlines the potential hazard of CCA on some vital organs, further testing may be required to establish the impacts on other functions.


Asunto(s)
Arseniatos/toxicidad , Contaminantes Ambientales/toxicidad , Animales , Arseniatos/metabolismo , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Contaminantes Ambientales/metabolismo , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR , Tamaño de los Órganos/efectos de los fármacos , Pruebas de Toxicidad Aguda
3.
Int J Antimicrob Agents ; 31(1): 37-45, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18006283

RESUMEN

Tuberculosis (TB) is a leading cause of death amongst infectious diseases. The low permeation of antimycobacterial agents and their difficult access to infected macrophages necessitate long-term use of high drug doses. Liposomes preferentially accumulate in macrophages, increasing the efficacy of antibiotics against intracellular parasites. In the present work, several rifabutin (RFB) liposomal formulations were developed and characterised and their in vivo profile was compared with free RFB following intravenous administration. With the RFB liposomal formulations tested, higher concentrations of the antibiotic were achieved in liver, spleen and lungs 24h post administration compared with free RFB. The concentration of RFB in these organs was dependent on the rigidity of liposomal lipids. The liposomal RFB formulation prepared with dipalmitoyl phosphatidylcholine:dipalmitoyl phosphatidylglycerol (DPPC:DPPG) was the most effective and was selected for biological evaluation in a mouse model of disseminated TB. Compared with mice treated with free RFB, mice treated with the DPPC:DPPG RFB formulation exhibited lower bacterial loads in the spleen (5.53 log(10) vs. 5.18 log(10)) and liver (5.79 log(10) vs. 5.41 log(10)). In the lung, the level of pathology was lower in mice treated with encapsulated RFB. These results suggest that liposomal RFB is a promising approach for the treatment of extrapulmonary TB in human immunodeficiency virus co-infected patients.


Asunto(s)
Antituberculosos/administración & dosificación , Rifabutina/administración & dosificación , Tuberculosis/tratamiento farmacológico , Animales , Antituberculosos/farmacocinética , Antituberculosos/uso terapéutico , Química Farmacéutica , Liposomas , Hígado/química , Hígado/microbiología , Pulmón/química , Pulmón/microbiología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Rifabutina/farmacocinética , Rifabutina/uso terapéutico , Bazo/química , Bazo/microbiología , Factores de Tiempo
4.
Med Trop (Mars) ; 68(2): 137-43, 2008 Apr.
Artículo en Francés | MEDLINE | ID: mdl-18630045

RESUMEN

This article presents follow-up data from the first patient in whom Mycobacterium ulcerans infection (MUI) was documented by PCR, genotyping and culture in the Republic of Congo-Brazzaville. Findings show the importance of regular clinical and microbiological evaluation for the disseminated form of the disease. The patient was probably infected in Pointe Noire where MUI has been described but never documented. Culture of specimens collected before antibiotic treatment showed that the bacterium was sensitive to the antibiotics being administered (streptomycin and rifampin) and was identical to isolates from Atlantic-coast regions of West Africa where MUI is endemic. The patient was treated with streptomycin and rifampin for 12 weeks in association with surgery. During treatment clinical examination was performed every day and microbiological analysis every two weeks. The duration of follow-up from the end of specific antibiotic treatment was 26 months. Medical treatment failed to prevent bone involvement and fistulae that were treated by surgery. However medical treatment may have limited dissemination of the disease. Serial microbiological evaluation was useful to detect bone involvement in this patient, but persistent positive gene amplification is not a proof of active disease. This study confirms that MUI is still endemic in the region of Pointe Noire. This finding underlines the need to optimize epidemiologic surveillance, laboratory diagnostic capabilities, and therapeutic management in the Republic of Congo-Brazzaville.


Asunto(s)
Úlcera de Buruli/diagnóstico , ADN Bacteriano/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Adulto , Antibacterianos/uso terapéutico , Biopsia , Úlcera de Buruli/terapia , Congo , Estudios de Seguimiento , Genotipo , Humanos , Masculino , Mycobacterium ulcerans/genética , Piel/patología
5.
J Healthc Qual Res ; 33(1): 23-32, 2018.
Artículo en Español | MEDLINE | ID: mdl-29463453

RESUMEN

INTRODUCTION: Pharmaceutical care to outpatients is currently one of the main occupations of hospital pharmacy services (PEX). There are several questionnaires to measure the satisfaction of the PEX of a pharmacy service, and the results of these questionnaires can generate improvement actions that result in satisfaction. OBJECTIVES: To verify if a satisfaction questionnaire for outpatients is valid for the generation of improvements in the care provided, and if after its implementation, the same questionnaire is able to detect changes in satisfaction. MATERIAL AND METHOD: Prospective study of a single center carried out in a tertiary hospital in 2015 and 2016. A questionnaire previously validated with 16 Likert-type items was used. Demographic and classification data were collected. A descriptive analysis was performed and the internal consistency was calculated using the Cronbach's α value. RESULTS: A total of 258 questionnaires were collected in 2015 and 493 in 2016. There were no differences in the baseline characteristics of the patients and users of the service. The items with the lowest satisfaction scores in 2015 (comfort of the waiting room, dispensing privacy, drug pick-up time and medication pick-up time) guided the improvement actions to be implemented. In 2016 there was an improvement in the waiting time until collection in 12.3% (p = 0.002); in the comfort of the waiting room 4.9% (p = 0.304); business hours for medication collection, 10.7% (p = 0.013); and in the confidentiality of the dispensation 4% (p = 0.292). The remaining scores fluctuated minimally, with no statistical significance at all. A 5.1% improvement in overall satisfaction was found (p < 0.001). Satisfaction values obtained as a whole were high. CONCLUSIONS: The satisfaction questionnaire is a valid instrument for generating actions to improve the care received in an outpatient unit of a pharmacy service. This same questionnaire is a tool to monitor the changes implemented to improve the care received.


Asunto(s)
Atención Ambulatoria , Satisfacción del Paciente , Servicio de Farmacia en Hospital , Medicamentos bajo Prescripción/provisión & distribución , Adulto , Confidencialidad , Grupos Diagnósticos Relacionados , Escolaridad , Humanos , Persona de Mediana Edad , Ocupaciones , Satisfacción del Paciente/estadística & datos numéricos , Relaciones Profesional-Paciente , Estudios Prospectivos , Mejoramiento de la Calidad , Encuestas y Cuestionarios , Centros de Atención Terciaria , Tiempo de Tratamiento
6.
J Nutr Health Aging ; 22(6): 664-675, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29806855

RESUMEN

Aging and disease-related malnutrition are well associated with loss of muscle mass and function. Muscle mass loss may lead to increased health complications and associated increase in health care costs, especially in hospitalized individuals. High protein oral nutritional supplements enriched with ß-hydroxy-ß-methylbutyrate (HP-ONS+HMB) have been suggested to provide benefits such as improving body composition, maintaining muscle mass and function and even decreasing mortality rates. The present review aimed to examine current evidence on the effect of HP-ONS+HMB on muscle-related clinical outcomes both in community and peri-hospitalization patients. Overall, current evidence suggests that therapeutic nutrition such as HP-ONS+HMB seems to be a promising tool to mitigate the decline in muscle mass and preserve muscle function, especially during hospital rehabilitation and recovery.


Asunto(s)
Desnutrición/dietoterapia , Desnutrición/prevención & control , Músculo Esquelético/fisiología , Sarcopenia/dietoterapia , Sarcopenia/prevención & control , Valeratos/uso terapéutico , Envejecimiento , Composición Corporal , Suplementos Dietéticos , Humanos , Fenómenos Fisiológicos Musculoesqueléticos/efectos de los fármacos , Estado Nutricional
7.
J Inherit Metab Dis ; 30(4): 615, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17694357

RESUMEN

The newborn screening programme started in Brazil (1976) through isolated initiatives, without governmental directions and/or policies. According to Health Ministry (2000) data the coverage was 55% and unevenly distributed. Only 17 out of 27 Brazilian states had more than 30% coverage. Public budgets covered only diagnostic examinations. There were no official data about assistance, patient follow-up or detected disorders. The creation of the National Programme (2001) has provided new perspective for newborn screening (NBS) in the public health system. It has provided important official data and established management and care units for each state: Reference Services in Newborn Screening. The programme screened about 13 million newborns from October 2001 to December 2005. The coverage increased to 80.2% (2005) and 74% of the states presented coverage of over 70%. Within 34 accredited Reference Services in 27 Brazilian states, all provide screening for PKU and CH. Ten of them provide screening for haemoglobinopathies as well, and three of them provide also for CF. The Reference Services altogether count on at least 170 health professionals, such as paediatricians, endocrinologists, nutritionists, psychologists and social workers. They are qualified to assist positive cases, within the policies established by the National Programme. There has been significant increase in NBS coverage and follow-up assuredness, including detected cases before the National Programme (10,935 positive cases) mostly in those regions where the programme did not exist. There has been significant evolution in the Newborn Screening as a Public Health Program in Brazil due to the government's commitment (federal and each component state).


Asunto(s)
Hipotiroidismo Congénito/diagnóstico , Tamizaje Neonatal/métodos , Fenilcetonurias/diagnóstico , Salud Pública/métodos , Brasil , Hipotiroidismo Congénito/sangre , Política de Salud , Humanos , Recién Nacido , Exámenes Obligatorios , Programas Nacionales de Salud , Fenilcetonurias/sangre , Atención Primaria de Salud/normas
8.
Chemotherapy ; 53(5): 344-55, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17785971

RESUMEN

BACKGROUND: The goal of this study was to develop an animal model of intestinal injury induced by 5-fluorouracil (5-FU) in pigs. METHODS: Six domestic pigs were used as control (healthy group) and another 6 malnourished pigs orally received 5-FU (treated group). After 4 weeks of treatment, pigs were sacrificed and jejunum, ileum and colon were isolated for histological, immunological and biochemical analyses. RESULTS: 5-FU caused a decrease in the intestinal mass. Disaccharidase, and phosphate alkaline activities, and glutathione redox cycle were disrupted by 5-FU. Histopathological alterations in the crypts and villous were greater in the small intestine than in the colon. 5-FU decreased the number of peripheral and intestinal leukocytes, promoting an increase in T-cytotoxic cells and a decrease in T-helper and B cells. CONCLUSION: This pig model of intestinal dysfunction closely mimics the common side effects of cancer chemotherapy in humans, and provides a useful tool for evaluating novel antimucotoxic agents.


Asunto(s)
Fluorouracilo/toxicidad , Intestinos/efectos de los fármacos , Modelos Animales , Porcinos , Animales , Peso Corporal/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Fluorouracilo/administración & dosificación , Glutatión/metabolismo , Mucosa Intestinal/citología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Intestinos/citología , Microscopía Electrónica de Transmisión , Oxidación-Reducción
9.
Exp Gerontol ; 41(1): 25-31, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16260109

RESUMEN

The effect of aging on basal and hypoxia/reoxygenation levels of both oxidative stress (protein carbonyl and TBARS) and antioxidative-enzyme activity (Cu/Zn-SOD; Mn-SOD; Catalase, CAT; Se-independent and Se-dependent glutathione peroxidase, GPX; glutathione transferase, GST and glutathione reductase, GR) has been studied in the cerebral cortex of adult and old rats. Oxidative stress markers increased with aging and show an age-dependent post-hypoxic response. Moreover, aging caused either no change (GST, GR and CAT) or an increase (Se-GPX, Cu/Zn-SOD, Mn-SOD) in the basal activity of the enzymes analysed. Only Se-independent GPX activity decreases. However, we detected an age-dependent response of SODs to the hypoxic injury. The early and sustained Cu/Zn-SOD activity rise in adult animals became late and weak in aged animals. Meanwhile, aging slowed the Mn-SOD post-hypoxic response although this activity was consistently higher in aged rats. Aging eliminated the post-hypoxic CAT response, but, perhaps offset by increased GPX activity, did not affect the GST response and slightly reduced post-hypoxic GR activity. In conclusion, aging rise basal ROS production, does not diminish or even increase the antioxidative-enzyme activity, and may slow but does not usually eliminate the enzymatic antioxidant response to the increased post-hypoxic ROS generation.


Asunto(s)
Envejecimiento/fisiología , Corteza Cerebral/enzimología , Hipoxia Encefálica/fisiopatología , Animales , Antioxidantes/metabolismo , Hipoxia Encefálica/enzimología , Peroxidación de Lípido , Masculino , Oxidación-Reducción , Estrés Oxidativo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
10.
Brain Res ; 1054(1): 88-94, 2005 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-16054596

RESUMEN

Aged brain shows reduced biological plasticity to meet emergency conditions such as ischemia, a process in which nitric oxide (NO) and apoptosis have been shown to play important roles. Using a model of transient global ischemia, we have analyzed the NO system and the p53, bax and bcl-2 response in the cerebral cortex of aged rats. Although immediately after ischemia the NO level is maintained, the reperfusion period increases NO concentrations together with the following: (i) greater bulk-protein nitration mainly due to a 50-kDa immunoreactive band; (ii) an increase in p53 protein; and (iii) an up-regulation of Bax together with a down-regulation of Bcl-2. These results match up with induced endothelial nitric oxide synthase expression immediately after ischemia and in neuronal nitric oxide synthase with the reperfusion. However, inducible nitric oxide synthase was not altered with ischemia/reperfusion. Altogether, these data suggest that NO production in cerebral cortex of aged ischemic animals is due to the constitutive NO synthase isoforms. This response is accompanied by the increased expression of pro-apoptotic proteins.


Asunto(s)
Envejecimiento/metabolismo , Isquemia Encefálica/metabolismo , Corteza Cerebral/metabolismo , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico/metabolismo , Animales , Western Blotting/métodos , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/fisiología , Humanos , Masculino , NADPH Deshidrogenasa/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Proteína p53 Supresora de Tumor/metabolismo , Proteína X Asociada a bcl-2
11.
Artículo en Inglés | MEDLINE | ID: mdl-26025886

RESUMEN

The main objective of this work was to develop a method to measure Leucine (Leu) and ß-hydroxymethylbutyrate (HMB) at basal levels in serum, urine, milk and brain microdialysates in rats. Ultrahigh performance liquid chromatography-electrospray-tandem mass spectrometry (UHPLC-ESI-MS/MS) was used as analytical technique. The sample treatment was simple and consisted of dilution with methanol and centrifugation for serum and urine, dilution with water and filtration with an Amicon filter for milk, and treatment with formic acid with no further dilution for microdialyzates. The procedures for sampling and the UHPLC-MS/MS parameters were accurately optimized to achieve the highest recoveries and to enhance the analytical characteristics of the method. For chromatographic separation, an Acquity UPLC BEH Amide column using acetonitrile-water gradient with formic acid as additive was used. The total run time was 4min. The analytical characteristics (accuracy, selectivity and sensitivity) of the proposed method were evaluated. The limits of detection (LODs) obtained ranged from 0.4 to 7ngmL(-1) and the limits of quantification (LOQs) from 1 to 22ngmL(-1). Precision, expressed as relative standard deviation (% RSD), was lower than 15% in all cases, and the determination coefficient (R(2)) was equal or higher than 99.0% with a residual deviation for each calibration point lower than ±25%. Mean recoveries were between 85 and 115%. The method was successfully applied to these matrices being able to detect significant differences between physiological situations, strains and stages of life.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Leucina/análisis , Valeratos/análisis , Animales , Animales Recién Nacidos , Química Encefálica , Ayuno/fisiología , Femenino , Lactancia/fisiología , Límite de Detección , Masculino , Leche/química , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
12.
Neuroscience ; 126(4): 879-87, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15207323

RESUMEN

This study examines the expression and cellular distribution pattern of nitric oxide synthase (NOS) isoforms, nitrotyrosine-derived complexes, and the nitric oxide (NO) production in the cerebellum of rats with cirrhosis induced by thioacetamide (TAA). The results showed local changes in the tissue distribution pattern of the NOS isoforms and nitrated proteins in the cerebellum of these animals. Particularly, eNOS immunoreactivity in perivascular glial cells of the white matter was detected only in TAA-treated animals. In addition, although neither neuronal NOS (nNOS) nor inducible NOS (iNOS) cerebellar protein levels appeared to be affected, the endothelial NOS (eNOS) isoform significantly increased its expression, and NO production slightly augmented in TAA-treated rats. These NOS/NO changes may contribute differently to the evolution of the hepatic disease either by maintaining the guanosine monophosphate-NO signal transduction pathways and the physiological cerebellar functions or by inducing oxidative stress and cell damage. This model gives rise to the hypothesis that the upregulation of the eNOS maintains the physiological production of NO, while the iNOS is silenced and the nNOS remains unchanged. The differential NOS-distribution and expression pattern may be one of the mechanisms involved to balance cerebellar NO production in order to minimize TAA toxic injury. These data help elucidate the role of the NOS/NO system in the development and progress of hepatic encephalopathy associated with TAA cirrhosis.


Asunto(s)
Cerebelo/metabolismo , Cirrosis Hepática Experimental/metabolismo , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico/metabolismo , Tirosina/análogos & derivados , Animales , Western Blotting/métodos , Modelos Animales de Enfermedad , Regulación Enzimológica de la Expresión Génica , Inmunohistoquímica/métodos , Cirrosis Hepática Experimental/inducido químicamente , Masculino , NADPH Deshidrogenasa/metabolismo , Nitratos/metabolismo , Óxido Nítrico Sintasa de Tipo I , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Nitritos/metabolismo , Ratas , Ratas Wistar , Tioacetamida , Tirosina/metabolismo , Regulación hacia Arriba
13.
J Chem Neuroanat ; 21(4): 289-94, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11429270

RESUMEN

The distribution of nitrergic nervous structures in the trout kidney was studied by peroxidase-linked ABC immunostaining procedures using a polyclonal antibody raised against the neuronal isoform of nitric oxide synthase. The nitrergic plexus reaches the kidney along the vasculature, mainly running with the postcardinal vein where nitrergic fibres, microganglia like cellular clusters and isolated neurones were detected. The atubular head-kidney only showed isolated nitrergic fibres close to the larger arteries. On the other hand, the collecting tubules, collecting ducts, large arteries and glomerular arterioles of the tubular middle and posterior trunks were innervated by nitrergic fibres even though immunoreactive neurones were also observed in close apposition to some tubular elements and large arteries. These results suggest that, according to morphofunctional differences between the fish and mammalian kidneys, nitrergic neural structures may be involved in the control of particular renal functions in the rainbow trout.


Asunto(s)
Riñón/enzimología , Óxido Nítrico Sintasa/metabolismo , Oncorhynchus mykiss/metabolismo , Animales , Inmunohistoquímica , Fibras Nerviosas/enzimología , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa de Tipo I
14.
Microsc Res Tech ; 43(1): 34-42, 1998 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9829457

RESUMEN

The frequency of astrocytes, microglia plus oligodendrocytes, and pericytes displaying nuclei was analyzed and quantified in 160-microm-wide strips of the parietal cortex (Par1 region) from young and aged Wistar rats. The study was performed on two groups of rats aged 3-4 and 32-36 months. Quantifications of the glial cell types and pericytes were made in 1-microm-thick sections stained with toluidine blue. Ultrathin sections were also made to analyze the ultrastructural features of these cells during aging. Astrocytes and pericytes increased in number by about 20% and 22%, respectively, with age. These increases were most significant in layers II-IV and V for both cellular types. Clusters of astrocytes were common in these layers of aging rats. The ultrastructural analysis also indicated changes in all cell types that stored inclusions and vacuoles with age, which were particularly abundant in microglial cells. End-feet astrocytes and pericytes surrounding the vascular wall also contained vacuoles and inclusions, and consequently the vascular wall increased in thickness. In conclusion, the aging process increased astrocyte and pericyte populations, but not microglia plus oligodendrocyte populations, in the rat parietal cortex. Although no significant change in nuclear size could be observed in any cell type, all glial cells as well as pericytes underwent morphological ultrastructural changes. These modifications may result from the need to correct possible homeostatic imbalances during aging.


Asunto(s)
Envejecimiento/fisiología , Neuroglía/fisiología , Neuroglía/ultraestructura , Lóbulo Parietal/ultraestructura , Pericitos/fisiología , Pericitos/ultraestructura , Animales , Recuento de Células , Senescencia Celular/fisiología , Microscopía Electrónica , Neuroglía/citología , Lóbulo Parietal/citología , Lóbulo Parietal/fisiología , Pericitos/citología , Ratas , Ratas Wistar
15.
Microsc Res Tech ; 43(1): 75-88, 1998 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9829462

RESUMEN

Neuronal and inducible nitric oxide synthase (nNOS and iNOS) and nitrotyrosine immunoreactivities were localized and semiquantitatively assessed in the cerebral cortex of aged rats by means of light microscopic immunocytochemistry and Western blotting, using a new series of specific polyclonal antibodies. In the aged rats the strongly nNOS-immunoreactive multipolar neurons found in layers II-VI of the cortex of young rats were seen in similar numbers, but showed varicose, vacuolated, and fragmented processes, with an irregular outline and loss of spines. A large number of more weakly nNOS-positive neurons, characterized by a ring of immunoreactive cytoplasm, and not seen in young rats, were observed in layers II-VI of aged rat cortex. While no iNOS-immunopositive neurons were found in the cortex of young rats, a large number of such neurons appeared throughout the aged rat cortex. Nitrotyrosine-positive cells outnumbered total NOS-positive neurons in the cortex of young rats, but this relation was inverted in the aged rats, although these showed a slight increase in the number and staining intensity of nitrotyrosine-positive cells. Western blots of brain extracts showed a several-fold increase in both nNOS- and iNOS-immunoreactive bands in the aged rat, but a less marked increase in nitrotyrosine-containing proteins. The results suggest that while nNOS and iNOS expression is substantially increased in the aged rat cortex, this is not necessarily accompanied by a proportionate increase in nitric oxide synthesis. The mechanisms underlying the increased expression of nNOS and iNOS, and the functional implications of this increase, require elucidation.


Asunto(s)
Envejecimiento/patología , Corteza Cerebral/química , Proteínas del Tejido Nervioso/análisis , Óxido Nítrico Sintasa/análisis , Tirosina/análisis , Albinismo , Animales , Western Blotting , Corteza Cerebral/patología , Inmunohistoquímica , Masculino , Óxido Nítrico Sintasa de Tipo I , Óxido Nítrico Sintasa de Tipo II , Ratas , Ratas Wistar , Tirosina/análogos & derivados
16.
Neurosci Lett ; 226(2): 99-102, 1997 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-9159499

RESUMEN

We studied the distribution of neuronal nitric oxide synthase (nNOS) in the rat liver with a specific polyclonal antibody by using immunocytochemical procedures in the light microscopic level. Immunoreactive varicose nerve fibers were found forming a dense plexus around the interlobular hepatic artery and the interlobular bile duct in the hepatic hilus, and in the hepatic artery ramifications of the portal triads. The density of nNOS positive nerve fibers decreases with successive portal ramifications, and some non-immune positive nerve fibers were found in the distal portions of the arterial vessels. The presence of the nNOS positive nerve fibers suggests that the possible main functional role could be related with the regulation of hepatic blood circulation and hepatobiliary activities.


Asunto(s)
Hígado/inervación , Fibras Nerviosas/enzimología , Neuronas/enzimología , Óxido Nítrico Sintasa/análisis , Animales , Conductos Biliares Intrahepáticos/inervación , Arteria Hepática/inervación , Inmunohistoquímica , Hígado/citología , Masculino , Sistema Porta/inervación , Ratas , Ratas Wistar
17.
Neurosci Lett ; 243(1-3): 45-8, 1998 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-9535109

RESUMEN

The aim of this work was to study the nitrergic innervation in the liver of the cat using immunocytochemical procedures. At the hepatic hilus, a rich plexus of neuronal nitric oxide synthase immunoreactive (nNOS-IR) nerve fibers and ganglia was detected around the interlobular branch of the bile duct. nNOS-IR nerve fibers were observed running with the components of the intralobular portal triads located close to the hepatic hilus, as well as with a few vessels and ducts of the deeper parenchyma. These latter fibers, beside others located in Glisson's capsule, occasionally showed short ramifications entering the parenchyma itself. The present results suggest that, in the cat liver, nNOS is involved in the autonomic control of hepatic blood flow, with a limited role in the regulation of hepatobiliary excretory activity and hepatocellular metabolic function.


Asunto(s)
Hígado/inervación , Fibras Nerviosas/enzimología , Óxido Nítrico Sintasa/análisis , Óxido Nítrico/análisis , Animales , Gatos , Ganglios Autónomos/química , Ganglios Autónomos/enzimología , Masculino , Fibras Nerviosas/química
18.
Trans R Soc Trop Med Hyg ; 76(3): 403-6, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7112662

RESUMEN

We compare results of one Bell and one Kato-Katz examination performed on each of 315 stool specimens from residents in an area in north-eastern Brazil endemic for schistosomiasis mansoni. The prevalence of Schistosome infection detected by the Bell technique was 76% and by the Kato-Katz technique was 63%. 81% (44/54) of the infections missed by a Kato-Katz smear were light infections (one of 50 epg range by Bell examination). Over, all, 55% (44/80) of stools in this egg count range by the Bell technique were negative on a single Kato-Katz smear. This implies that five Kato-Katz smears per stool would ensure a 95% probability (0.55(5) X 100) of detecting such light infections. However, a single Kato-Katz smear detected eggs in 97% (124/128) of stools with a Bell count greater than 100 epg. For stools positive by both methods the egg counts per gram of stool were higher (p less than 0.001) by Kato-Katz examination. Geometric mean egg counts for the infected population were 199 epg by the Kato-Katz and 92 epg by the Bell methods. 64% (59 v. 36) more persons were classified as heavily infected (greater than 400 epg) by the Kato-Katz method than by the Bell method. The differing measurements of schistosome infection obtained with the Bell and Kato-Katz methods must be considered when comparing data on morbidity-infection relationships.


Asunto(s)
Heces/parasitología , Esquistosomiasis/parasitología , Humanos , Recuento de Huevos de Parásitos/métodos , Schistosoma mansoni/aislamiento & purificación
19.
Clin Nutr ; 23(1): 43-51, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14757392

RESUMEN

BACKGROUND & AIMS: We have previously reported the antifibrotic effect of dietary nucleotides in cirrhotic rats. In this work, we used primary rat hepatocytes, a liver stellate cell line (CFSC-2G) and co-cultures of both cell types to investigate the effects of exogenous nucleosides on the gene expression of various extracellular matrix components and on markers of liver function, and to ascertain whether the effects found in vivo are due to CFSC-2G, hepatocytes, or are the consequence of cell-cell interactions. RESULTS: Nucleosides enhanced fibronectin, laminin, and alpha1(I) procollagen levels in CFSC-2G and hepatocytes, as well as collagen synthesis and secretion in CFSC-2G. In contrast, nucleosides lowered fibronectin, laminin and alpha1(I) procollagen levels, and decreased collagen synthesis in co-cultures. Matrix metalloproteinase-13 content and collagen secretion increased in co-cultures incubated with nucleosides. Albumin increased in hepatocytes and co-cultures incubated in the presence of nucleosides. CONCLUSIONS: Nucleosides modulate the production of extracellular matrix in single cultures of hepatocytes and of CFSC-2G, and in co-cultures. This effect seems to be regulated at the translational level. The opposite behavior of single cultures and co-cultures is probably due to the fact that the latter model reproduces many of the physical and functional relationships observed in vivo between hepatocytes and stellate cells.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Matriz Extracelular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hígado/citología , Nucleósidos/administración & dosificación , Animales , Línea Celular , Técnicas de Cocultivo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiología , Proteínas de la Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/fisiología , Laminina/metabolismo , Hígado/fisiología , Masculino , Modelos Animales , Procolágeno/metabolismo , Ratas , Ratas Wistar
20.
Clin Nutr ; 22(4): 391-9, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12880607

RESUMEN

BACKGROUND & AIMS: Dietary nucleotides are reported to influence the growth and functioning of the liver. The objective of the study was to evaluate the uptake and incorporation of exogenous nucleosides by hepatic cells, and the potential implications for cell proliferation and function. METHODS: Liver stellate cell line CFSC-2G and primary hepatocytes in single and mixed cultures were exposed to mixtures of nucleosides and the concentrations of nucleoside derivatives were determined in the cultures, by high-performance liquid chromatography. Cell proliferation (DNA synthesis, cell cycle) and function (adenylate charge, albumin content, mitochondrial succinate dehydrogenase activity) were also evaluated. RESULTS: The exogenous nucleosides increased the intracellular concentrations of UTP, UDP-glucose, CDP-choline and NAD(+), in the single cultures of CFSC-2G and hepatocytes. Modification of the intracellular nucleotide pool paralleled changes in cell functional status, as indicated by increased adenylate charge and albumin content in hepatocyte cultures and in their co-cultures with CFSC-2G, and by increased succinate dehydrogenase activity in hepatocytes. CONCLUSION: Exogenous nucleosides were taken up by CFSC-2G and hepatocytes, which modified the intracellular concentrations of nucleotides, improved the functional status of hepatocytes, and partially restored the impaired adenylate charge of the co-cultures.


Asunto(s)
Hepatocitos/efectos de los fármacos , Hepatocitos/fisiología , Hígado/citología , Nucleósidos/administración & dosificación , Albúminas/análisis , Animales , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , División Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Técnicas de Cocultivo , ADN/biosíntesis , Hígado/fisiología , Masculino , Nucleósidos/metabolismo , Nucleósidos/farmacología , Ratas , Ratas Wistar
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