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1.
Z Naturforsch C J Biosci ; 77(11-12): 525-529, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36112782

RESUMEN

Essential oils obtained from medicinal plants show high therapeutic potential against several types of pathologies, including Alzheimer's disease. The purpose of this work was to study the chemical composition and anticholinesterase inhibitory activity of the essential oil obtained from Lepisanthes rubiginosa leaves collected from Malaysia. Twenty-four components were identified using gas chromatography-flame ionization detection (GC-FID) and gas chromatography/mass spectrometry (GC-MS), which represent 99.5% of the essential oil. The identified major components include α-cadinol (40.0%), safrole (12.6%), α-amorphene (9.5%), (E)-isosafrole (5.0%), δ-cadinene (4.2%), and t-muurolol (4.1%). Anticholinesterase activity was assessed using Ellman method, and the essential oil demonstrated a moderate inhibitory activity against acetylcholinesterase (I%: 75.2%) and butyrylcholinesterase (I%: 70.2%) at conconcetration of 1000 µg/mL. The current study is the first to report chemical composition and anticholinesterase activity of the essential oil obtained from L. rubiginosa, which may have implications on the characterization, pharmaceutical, and therapeutic applications of Lepisanthes genus essential oils.


Asunto(s)
Aceites Volátiles , Aceites Volátiles/química , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa , Butirilcolinesterasa , Cromatografía de Gases y Espectrometría de Masas
2.
J Chem Inf Model ; 60(12): 5832-5852, 2020 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-33326239

RESUMEN

We present a supercomputer-driven pipeline for in silico drug discovery using enhanced sampling molecular dynamics (MD) and ensemble docking. Ensemble docking makes use of MD results by docking compound databases into representative protein binding-site conformations, thus taking into account the dynamic properties of the binding sites. We also describe preliminary results obtained for 24 systems involving eight proteins of the proteome of SARS-CoV-2. The MD involves temperature replica exchange enhanced sampling, making use of massively parallel supercomputing to quickly sample the configurational space of protein drug targets. Using the Summit supercomputer at the Oak Ridge National Laboratory, more than 1 ms of enhanced sampling MD can be generated per day. We have ensemble docked repurposing databases to 10 configurations of each of the 24 SARS-CoV-2 systems using AutoDock Vina. Comparison to experiment demonstrates remarkably high hit rates for the top scoring tranches of compounds identified by our ensemble approach. We also demonstrate that, using Autodock-GPU on Summit, it is possible to perform exhaustive docking of one billion compounds in under 24 h. Finally, we discuss preliminary results and planned improvements to the pipeline, including the use of quantum mechanical (QM), machine learning, and artificial intelligence (AI) methods to cluster MD trajectories and rescore docking poses.


Asunto(s)
Antivirales/química , Tratamiento Farmacológico de COVID-19 , SARS-CoV-2/efectos de los fármacos , Proteínas no Estructurales Virales/química , Inteligencia Artificial , Sitios de Unión , Simulación por Computador , Bases de Datos de Compuestos Químicos , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Simulación del Acoplamiento Molecular , Conformación Proteica , Glicoproteína de la Espiga del Coronavirus/química , Relación Estructura-Actividad
3.
PLoS One ; 14(10): e0222404, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31600212

RESUMEN

Conjugated linoleic acid was detected in rabbit caecotrophs, due to the presence of microbial lipid activity in rabbit cecum. However, the effect of CLA as a functional food in growing rabbit is not well established. Therefore, this study was conducted to determine the effect of CLA on production, meat quality, and its nutrigenomic effect on edible parts of rabbit carcass including skeletal muscle, liver, and adipose tissue. Therefore, seventy five weaned V-Line male rabbits, 30 days old, were randomly allocated into three dietary treatments receiving either basal control diet, diet supplemented with 0.5% (CLAL), or 1% CLA (CLAH). Total experimental period (63 d) was segmented into 7 days adaptation and 56 days experimental period. Dietary supplementation of CLA did not alter growth performance, however, the fat percentage of longissimus lumborum muscle was decreased, with an increase in protein and polyunsaturated fatty acids (PUFA) percentage. Saturated fatty acids (SFA) and mono unsaturated fatty acids (MUFA) were not increased in CLA treated groups. There was tissue specific sensing of CLA, since subcutaneous adipose tissue gene expression of PPARA was downregulated, however, CPT1A tended to be upregulated in liver of CLAL group only (P = 0.09). In skeletal muscle, FASN and PPARG were upregulated in CLAH group only (P ≤0.01). Marked cytoplasmic vacuolation was noticed in liver of CLAH group without altering hepatocyte structure. Adipocyte size was decreased in CLA fed groups, in a dose dependent manner (P <0.01). Cell proliferation determined by PCNA was lower (P <0.01) in adipose tissue of CLA groups. Our data indicate that dietary supplementation of CLA (c9,t11-CLA and t10,c12- CLA) at a dose of 0.5% in growing rabbit diet produce rabbit meat rich in PUFA and lower fat % without altering growth performance and hepatocyte structure.


Asunto(s)
Dieta , Ácidos Grasos Insaturados/metabolismo , Ácidos Linoleicos Conjugados/farmacología , Músculo Esquelético/metabolismo , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Composición Corporal/efectos de los fármacos , Suplementos Dietéticos , Ácidos Grasos/metabolismo , Humanos , Lípidos/análisis , Hígado/metabolismo , Carne/análisis , Músculo Esquelético/efectos de los fármacos , Nutrigenómica , Conejos , Grasa Subcutánea/efectos de los fármacos , Grasa Subcutánea/metabolismo
4.
Osteoporos Int ; 29(10): 2251-2260, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29943190

RESUMEN

Information regarding the prevalence and risk of osteoporosis among American Indian (AI) women is limited. This study showed that with increasing AI blood quantum, the prevalence of osteoporosis at the hip based on BMD T-scores decreased and this appeared to be independent of other risk factors. INTRODUCTION: This study was designed to investigate the effects of AI blood quantum (BQ) on osteoporosis prevalence and risk in a cohort of AI women in Oklahoma. METHODS: Women (n = 301), aged 50 years and older, were recruited to participate in the Oklahoma American Indian Women's Osteoporosis Study. Baseline bone density, fracture history, bone biochemical markers, and potential risk factors were assessed. Participants were stratified by AI BQ into BQ1 ≤ 25%, BQ2 = 25-49%, BQ3 = 50-74%, and BQ4 = 75-100%. The effects of BQ on the prevalence and risk of osteoporosis were evaluated. RESULTS: Based on T-scores, one in approximately eight women in the study was osteoporotic at one or more sites. The prevalence of osteoporosis decreased (p < 0.05) with increasing BQ, especially at the hip, trochanteric, and intertrochanter regions. No differences in bone-specific alkaline phosphatase and C-telopeptide were observed across BQ that could account for the differences in bone density. 25-OH vitamin D decreased with increasing BQ, but mean for each BQ1-4 was > 40 ng/mL. Fracture history did not differ across BQ, and though 52% of the population consumed less than the RDA for calcium, no effect of BQ was observed. CONCLUSIONS: In this cohort of women who identified as AI, greater Indian BQ was associated with a decrease in the prevalence of osteoporosis.


Asunto(s)
Indígenas Norteamericanos/estadística & datos numéricos , Osteoporosis Posmenopáusica/etnología , Anciano , Antropometría/métodos , Composición Corporal/fisiología , Densidad Ósea/fisiología , Calcio de la Dieta/administración & dosificación , Estudios Transversales , Suplementos Dietéticos , Femenino , Humanos , Persona de Mediana Edad , Oklahoma/epidemiología , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/etnología , Fracturas Osteoporóticas/fisiopatología , Prevalencia , Medición de Riesgo/métodos
5.
Eur J Clin Nutr ; 71(9): 1121-1128, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28656968

RESUMEN

BACKGROUND/OBJECTIVES: This study evaluated nutrition after oesophago-gastric resection and the influence of home jejunostomy feeding in the six months after surgery. SUBJECTS/METHODS: Data on nutritional intake and physiologic measures were collected as part of a randomised trial with measurements taken before and up to six months after surgery. RESULTS: A total of 41 participants (32 oesophagectomy, 9 total gastrectomy) received home jejunostomy feeding (n=18) or usual care without feeding (n=23). At hospital discharge, oral intakes were adequate for energy and protein in 9% and 6%, respectively. By three and six months, these values had increased to 61% and 55%, 94% and 77% respectively. Six participants (26%) who received usual care required rescue feeding. Six weeks after hospital discharge, energy intakes were met in those who received jejunal feeding because of the contribution of enteral nutrition. Jejunal feeding did not affect oral intake, being similar in both groups (fed: 77% estimated need, usual care: 79%). At three months, inadequate micronutrient intakes were seen in over one third. Compared to baseline values, six weeks after surgery, weight loss exceeding 5% was seen in 5/18 (28%) who received feeding, 14/17 (82%) who received usual care and 5/6 (83%) of those who required rescue feeding, P=0.002. Weight loss averaged 4.1% (fed), 10.4% (usual care) and 9.2% (rescue fed), P=0.004. These trends persisted out to six months. CONCLUSIONS: Supplementary jejunostomy feeding made an important contribution to meeting nutrition after oesophago-gastric resection. Importantly, oral nutritional intake was not compromised dispelling the assertion that jejunal feeding deincentivises patients from eating.


Asunto(s)
Ingestión de Energía , Nutrición Enteral , Esofagectomía , Femenino , Gastrectomía , Humanos , Irlanda , Yeyunostomía , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud , Estado Nutricional , Periodo Posoperatorio , Estudios Prospectivos , Resultado del Tratamiento
6.
BMC Nephrol ; 18(1): 101, 2017 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-28340561

RESUMEN

BACKGROUND: Contrast induced nephropathy (CIN) is the commonest cause of iatrogenic renal injury and its incidence has increased with the advent of complex endovascular procedures. Evidence suggests that ascorbic acid (AA) has a nephroprotective effect in percutaneous coronary interventions when contrast media are used. A variety of biomarkers (NGAL, NGAL:creatinine, mononuclear cell infiltration, apoptosis and RBP-4) in both the urine and kidney were assayed using a mouse model of CIN in order to determine whether AA can reduce the incidence and/or severity of renal injury. METHODS: Twenty-four BALB/c mice were divided into 4 groups. Three groups were exposed to high doses of contrast media (omnipaque) in a well-established model of CIN, and then treated with low or high dose AA or placebo (saline). CIN severity was determined by measurement of urinary neutrophil gelatinase-associated lipocalin (NGAL):creatinine at specific time intervals. Histological analysis was performed to determine the level of mononuclear inflammatory infiltration as well as immunohistochemistry to determine apoptosis in the glomeruli by staining for activated caspase-3 and DNA nicking (TUNEL assays). Reverse transcriptase PCR (rtPCR) of mRNA transcripts prepared from mRNA extracted from mouse kidneys was also performed for both lipocalin-2 (Lcn2) encoding NGAL and retinol binding protein-6 (RBP4) genes. NGAL protein expression was also confirmed by ELISA analysis of kidney lysates. RESULTS: Urinary NGAL:creatinine ratio was significantly lower at 48 h with a 44% and 62% (204.3µg/mmol versus 533.6µg/mmol, p = 0.049) reduction in the low and high dose AA groups, respectively. The reduced urinary NGAL:creatinine ratio remained low throughout the time period assessed (up to 96 h) in the high dose AA group. In support of the urinary analysis ELISA analysis of NGAL in kidney lysates also showed a 57% reduction (12,576 ng/ml versus 29,393 ng/ml) reduction in the low dose AA group. Immunohistochemistry for apoptosis demonstrated decreased TUNEL and caspase-3 expression in both low and high dose AA groups. CONCLUSIONS: Ascorbic acid reduced the frequency and severity of renal injury in this murine model of CIN. Further work is required to establish whether AA can reduce the incidence of CIN in humans undergoing endovascular procedures.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Medios de Contraste/toxicidad , Yohexol/toxicidad , Riñón/efectos de los fármacos , Lesión Renal Aguda/metabolismo , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/efectos de los fármacos , Caspasa 3/metabolismo , Creatinina/orina , Modelos Animales de Enfermedad , Procedimientos Endovasculares , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Riñón/metabolismo , Riñón/patología , Lipocalina 2/efectos de los fármacos , Lipocalina 2/metabolismo , Lipocalina 2/orina , Ratones , Ratones Endogámicos BALB C , Proteínas Plasmáticas de Unión al Retinol/efectos de los fármacos , Proteínas Plasmáticas de Unión al Retinol/metabolismo
7.
Mar Pollut Bull ; 100(1): 327-333, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26323859

RESUMEN

Fungi of the Ascomycota phylum were isolated from oil-soaked sand patties collected from beaches following the Deepwater Horizon oil spill. To examine their ability to degrade oil, fungal isolates were grown on oiled quartz at 20°C, 30°C and 40°C. Consistent trends in oil degradation were not related to fungal species or temperature and all isolates degraded variable quantities of oil (32-65%). Fungal isolates preferentially degraded short (

Asunto(s)
Ascomicetos/aislamiento & purificación , Ascomicetos/metabolismo , Contaminación por Petróleo , Petróleo/metabolismo , Alcanos/química , Alcanos/metabolismo , Biodegradación Ambiental , Contaminantes Ambientales/química , Contaminantes Ambientales/metabolismo , Golfo de México , Peso Molecular , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo , Cuarzo , Dióxido de Silicio
8.
Int J Obes (Lond) ; 39(1): 98-104, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23924758

RESUMEN

BACKGROUND: Environmental exposures during critical periods of prenatal and early postnatal life affect the development of mammalian body weight regulatory mechanisms, influencing lifelong risk of obesity. The specific biological processes that mediate the persistence of such effects, however, remain poorly understood. OBJECTIVE: The objectives of this study were to determine the developmental timing and physiological basis of the obesity-promoting effect previously reported in offspring of obese agouti viable yellow (A(vy)/a) mothers. DESIGN: Newborn offspring of obese A(vy)/a and lean (a/a) mothers were cross-fostered shortly after birth to study separately the effects of in utero or suckling period exposure to A(vy)/a dams. Body composition, food intake, physical activity and energy expenditure were measured in offspring shortly after weaning and in adulthood. RESULTS: Offspring of obese A(vy)/a dams paradoxically experienced fetal growth restriction, which was followed by adult-onset obesity specifically in females. Our main analyses focused on wild-type (a/a) offspring, because a subset of adult A(vy)/a offspring contracted a kidney disease resembling diabetic nephropathy. Detailed physiological characterization demonstrated that, both shortly after weaning and in adulthood, female wild-type mice born to A(vy)/a mothers are not hyperphagic but have reduced physical activity and energy expenditure. No such coordinated changes were detected in male offspring. Mediational regression analysis of our longitudinal data supported a causal pathway in which fetal growth restriction persistently reduces physical activity, leading to adult obesity. CONCLUSIONS: Our data are consistent with several recent human epidemiological studies showing female-specific effects of perinatal nutritional restriction on later obesity, and provide the novel mechanistic insight that this may occur via permanent and sex-specific changes in one's inherent propensity for physical activity.


Asunto(s)
Animales Recién Nacidos , Retardo del Crecimiento Fetal/metabolismo , Hipotálamo/metabolismo , Obesidad/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Animales , Metilación de ADN , Ingestión de Alimentos , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Hipotálamo/fisiopatología , Ratones , Actividad Motora , Obesidad/fisiopatología , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología
9.
Bioorg Med Chem Lett ; 21(19): 5863-5, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21855334

RESUMEN

Stimulation of toll-like receptor 2 (TLR2) by bacterial lipoproteins induces fast non-specific immune responses against pathogens followed by slow but specific adaptive immune responses. Development of synthetic TLR2 agonists/antagonists would be useful in the prevention of different infectious and immunologic disorders. The current study reports synthesis and TLR2 activity of two simple TLR2 ligands, which feature minimal structural requirement for TLR2 activity (two long lipid chains) and stimulate agonistic activity at nanomolar concentration.


Asunto(s)
Lipopéptidos/síntesis química , Lipopéptidos/farmacología , Receptor Toll-Like 2/metabolismo , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Células HEK293 , Humanos , Inmunidad Innata , Ligandos , Lipopéptidos/química , Lipopéptidos/inmunología , Luciferasas/análisis , Conformación Molecular , Estereoisomerismo , Receptor Toll-Like 2/biosíntesis , Receptor Toll-Like 2/química
10.
Neuroscience ; 171(1): 187-95, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-20801195

RESUMEN

Previous studies have demonstrated that catecholaminergic, tyrosine hydroxylase (TH)-immunoreactive (IR) perikarya and fibers are widely distributed in the human hypothalamus. Since TH is the key and rate-limiting enzyme for catecholaminergic synthesis, these IR neurons may represent dopaminergic, noradrenergic or adrenergic neural elements. However, the distribution and morphology of these neurotransmitter systems in the human hypothalamus is not entirely known. Since the different catecholaminergic systems can be detected by identifying the neurons containing the specific key enzymes of catecholaminergic synthesis, in the present study we mapped the catecholaminergic elements in the human hypothalamus using immunohistochemistry against the catecholaminergic enzymes, TH, dopamine beta-hydroxylase (DBH) and phenylethanolamine-N-methyltransferase (PNMT). Only a few, PNMT-IR, adrenergic neuronal elements were found mainly in the infundibulum and the periventricular zone. DBH-IR structures were more widely distributed in the human hypothalamus occupying chiefly the infundibulum/infundibular nucleus, periventricular area, supraoptic and paraventricular nuclei. Dopaminergic elements were detected by utilizing double label immunohistochemistry. First, the DBH-IR elements were visualized; then the TH-IR structures, that lack DBH, were detected with a different chromogen. In our study, we conclude that all of the catecholaminergic perikarya and the majority of the catecholaminergic fibers represent dopaminergic neurons in the human hypothalamus. Due to the extremely small number of PNMT-IR, adrenergic structures in the human hypothalamus, the DBH-IR fibers represent almost exclusively noradrenergic neuronal processes. These findings suggest that the juxtapositions between the TH-IR and numerous peptidergic systems revealed by previous reports indicate mostly dopaminergic synapses.


Asunto(s)
Mapeo Encefálico , Catecolaminas/metabolismo , Hipotálamo/citología , Neuronas/metabolismo , Anciano , Anciano de 80 o más Años , Dopamina beta-Hidroxilasa/metabolismo , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Neuronas/citología , Feniletanolamina N-Metiltransferasa/metabolismo , Cambios Post Mortem , Tirosina 3-Monooxigenasa/metabolismo
11.
J Med Chem ; 51(1): 167-72, 2008 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-18072728

RESUMEN

The development of 16 self-adjuvanting group A streptococcal vaccine candidates, composed of (i) a universal helper T-cell epitope (P25), (ii) a target GAS B-cell epitope (J14), and (iii) a lipid moiety, is described. Systemic J14-specific IgG antibodies were detected following subcutaneous immunization of BALB/c (H-2 (d)) mice with each construct without the need for an additional adjuvant. The effect of changing the order of P25, J14, and lipid moiety attachment or incorporation of P25 and J14 into a lipid-core peptide system on antibody titers was assessed. The point of lipid moiety attachment had the greatest influence on systemic J14-specific IgG antibody titers. Overall, the best vaccines featured a C-terminal lipid moiety, conjugated through a lysine residue to P25 at the N-terminus, and J14 on the lysine side chain.


Asunto(s)
Aminoácidos/química , Lípidos/química , Vacunas Estreptocócicas/síntesis química , Streptococcus pyogenes/inmunología , Vacunas de Subunidad/síntesis química , Animales , Epítopos de Linfocito B , Epítopos de Linfocito T , Femenino , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Vacunas Estreptocócicas/inmunología , Relación Estructura-Actividad , Vacunas de Subunidad/inmunología , Vacunas Sintéticas/inmunología
12.
Br J Anaesth ; 90(4): 504-7, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12644425

RESUMEN

BACKGROUND: Possible utility of high-dose i.v. melatonin as an anaesthetic adjuvant has not been studied. This study compared its effects with thiopental and propofol. METHODS: Sprague Dawley rats were assigned to receive bolus or cumulative i.v. doses of melatonin, thiopental or propofol. Righting reflex, hindpaw withdrawal to a noxious stimulus, response to tail clamping and haemodynamic effects were assessed. RESULTS: Melatonin caused a dose-dependent increase in paw withdrawal threshold and the percent of rats displaying loss of the righting reflex. Melatonin was comparable to thiopental and propofol in terms of its rapid onset of hypnosis. The mean ED(50) values for loss of righting reflex were 5.4 (SEM 1.2), 12.5 (1.1) and 178 (1.1) mg kg(-1) for propofol, thiopental and melatonin, respectively. The percent of rats displaying loss of response to tail clamping was greater with propofol than with melatonin (P<0.05). Haemodynamic changes produced by melatonin or propofol were similar in onset and magnitude. CONCLUSIONS: I.V. melatonin can exert hypnotic effects similar to those observed with thiopental and propofol. Melatonin exhibited significant antinociceptive effects but was less effective in abolishing the response to tail clamping.


Asunto(s)
Adyuvantes Anestésicos/farmacología , Anestésicos Intravenosos/farmacología , Melatonina/farmacología , Umbral del Dolor/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Hemodinámica/efectos de los fármacos , Masculino , Dimensión del Dolor/métodos , Propofol/farmacología , Ratas , Ratas Sprague-Dawley , Reflejo/efectos de los fármacos , Tiopental/farmacología
13.
J Ethnopharmacol ; 83(3): 209-17, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12426088

RESUMEN

In this study the long term (6 months) toxicological effect of varying levels of Catha edulis leaves were examined on the plasma concentration of liver enzymes as well as the histopathology of tissue sections of the liver. Both biochemical and histopathological data presented demonstrate signs of C. edulis toxicity. Our results show a significant increase in plasma levels of Alkaline phosphatase (ALP), Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) with all levels of C. edulis leaves tested and throughout the treatment period. The increase of ALP was more prominent than both ALT and AST at the higher level of 30%. Plasma levels of AST though were only moderately increased at the higher level of 30% at the early stage of treatment (3 months) it significantly increased with all levels of C. edulis leaves in the long term (4-6 months). In addition, a time-dependent gradual increase in indirect bilirubin with a concomitant decrease in direct bilirubin levels were observed with the lower level of C. edulis (10%) with no signs of haemolysis. Histopathology of tissue sections of liver display evidences of increasing chronic inflammation with porto-portal fibrosis in the tissue sections obtained from animals treated with both 20 and 30% C. edulis.


Asunto(s)
Catha/toxicidad , Hígado/efectos de los fármacos , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Aspartato Aminotransferasas/sangre , Relación Dosis-Respuesta a Droga , Hígado/patología , Hojas de la Planta , Conejos
14.
Int Endod J ; 35(9): 775-83, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12449029

RESUMEN

AIM: The purpose of this study was to evaluate healing responses following repair of furcation perforations, with and without an internal matrix. Two matrix materials, HAPSET (65% non-resorbable hydroxyapatite and 35% plaster of paris) and hydroxyapatite were compared. METHODOLOGY: Four adult female baboons (Papio anubis) served as experimental models. Furcation perforations were made in the molar and premolar teeth, which were then randomly assigned to one of the five groups, according to the method of perforation repair: 1 Experimental group 1 (16 teeth): The matrix material was HAPSET and the sealing material, amalgam. 2 Experimental group 2 (16 teeth): The matrix material was hydroxyapatite and the sealing material, amalgam. 3 Experimental group 3 (16 teeth): No matrix was placed. The sealing material was amalgam. 4 Positive control group (16 teeth): The perforation was not sealed. 5 Negative control group (16 teeth): No perforation was made. The animals were sacrificed at 1 week and 1, 3 and 7 months. Specimens were prepared for examination with light microscopy. RESULTS: The data revealed that when amalgam was used alone without a matrix, there was marked extrusion of the material into the underlying bone with an associated severe inflammatory response, which continued throughout the observational period. When an internal matrix was used, there was an initial acute inflammatory response that diminished with time such that at 7 months, 75% of these specimens were free of inflammation. There was no difference in the tissue response to the different matrix materials. HAPSET and hydroxyapatite underwent connective tissue encapsulation in the early stages followed by new bone deposition in direct contact with the materials. CONCLUSIONS: Within this animal model healing responses are better when an internal matrix, whether HAPSET or hydroxyapatite, is used in the repair of furcation perforations.


Asunto(s)
Proceso Alveolar/lesiones , Materiales Biocompatibles/uso terapéutico , Sustitutos de Huesos/uso terapéutico , Sulfato de Calcio/uso terapéutico , Cavidad Pulpar/lesiones , Durapatita/uso terapéutico , Raíz del Diente/lesiones , Proceso Alveolar/patología , Proceso Alveolar/cirugía , Animales , Diente Premolar , Tejido Conectivo/patología , Amalgama Dental , Cavidad Pulpar/patología , Cavidad Pulpar/cirugía , Modelos Animales de Enfermedad , Epitelio/patología , Femenino , Células Gigantes/patología , Diente Molar , Osteoblastos/patología , Osteoclastos/patología , Osteogénesis , Papio , Bolsa Periodontal/patología , Distribución Aleatoria , Materiales de Obturación del Conducto Radicular , Obturación del Conducto Radicular , Factores de Tiempo , Raíz del Diente/patología , Raíz del Diente/cirugía , Cicatrización de Heridas
15.
Phytother Res ; 16(2): 127-32, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11933113

RESUMEN

In this study the short term (3 months) toxicological effects of varying levels of Catha edulis leaves were examined on the plasma concentration of liver enzymes and the histopathology of tissue sections of various organs including the liver, kidneys, spleen and testis. Both the biochemical and histopathological data demonstrated, initial signs of Catha edulis toxicity. Our results show a significant increase in plasma levels of alkaline phosphatase (ALP) and alanine aminotransferase (ALT) with all levels of Catha edulis leaves tested and throughout the treatment period. The increase of ALP was more prominent than that of ALT. The plasma levels of aspartate aminotransferase (AST) were only moderately increased at the higher dose (30%) in the later stages of treatment. In addition, a time-dependent gradual increase in indirect bilirubin with a concomitant decrease in direct bilirubin levels was observed with the 30% Catha edulis with no signs of haemolysis. The histopathology of tissue sections of the liver displayed evidence of congestion of the central liver veins as well as acute hepatocellular degenerative and regenerative activities in the tissue sections obtained from animals treated with both 20% and 30% Catha edulis. Similarly, histopathological examination of the tissue sections of the kidneys showed some lesions, and the degree of the lesion increased as the dose of Catha edulis leaves increased including: the presence of fat droplets particularly seen in the upper cortical tubules; acute cellular swelling; hyaline tubules; and acute tubular nephrosis. In contrast, Catha edulis treatment did not affect the spleen and increased the rate of spermatogenesis in male rabbits with the spermatozoa being quite evident, the Leydig cells were in good condition and were not affected by the doses given.


Asunto(s)
Catha/toxicidad , Enzimas/efectos de los fármacos , Hojas de la Planta/toxicidad , Alanina Transaminasa/efectos de los fármacos , Alanina Transaminasa/metabolismo , Fosfatasa Alcalina/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Animales , Aspartato Aminotransferasas/efectos de los fármacos , Aspartato Aminotransferasas/metabolismo , Bilirrubina/metabolismo , Dieta , Enzimas/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Conejos , Testículo/efectos de los fármacos , Testículo/patología , Factores de Tiempo
16.
J Biomed Mater Res ; 58(6): 651-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11745517

RESUMEN

Hydroxyapatite coatings have been deposited on titanium cp by plasma spray, sol-gel, and sputtering techniques for dental implant applications. The latter two techniques are of current interest, as they allow coatings of micrometer dimensions to be deposited. Coating morphology, composition, and structure have been investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). All coatings were homogeneous and exhibited a rough morphology suitable for implant applications. The sputtered (after annealing), plasma spray, and sol-gel coatings all showed diffraction peaks corresponding to hydroxyapatite. The surface contaminants were observed to be different for the different coating types. The sputtered coatings were found to have a composition most similar to hydroxyapatite; the sol-gel deposits also showed a high concentration of hydroxyl ions. A discrepancy in the Ca/P ratio was observed for the plasma spray coatings, and a small concentration of carbonate ions was found in the sputter-deposited coatings. The in vitro cell-culture studies using MG63 osteoblast-like cells demonstrated the ability of cells to proliferate on the materials tested. The sol-gel coating promotes higher cell growth, greater alkaline phosphatase activity, and greater osteocalcin production compared to the sputtered and plasma-sprayed coatings.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Durapatita/química , Metalurgia/métodos , Titanio/química , Fosfatasa Alcalina/análisis , Calcio/análisis , División Celular/efectos de los fármacos , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Materiales Biocompatibles Revestidos/toxicidad , Durapatita/toxicidad , Geles , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Osteoblastos/efectos de los fármacos , Osteocalcina/biosíntesis , Fósforo/análisis , Polvos , Análisis Espectral , Difracción de Rayos X
17.
AJR Am J Roentgenol ; 175(5): 1449-52, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11044061

RESUMEN

OBJECTIVE: We sought to determine if dedicated gastrointestinal technologists could be trained to properly perform esophagography and double-contrast barium enema examinations. SUBJECTS AND METHODS: Ninety-four patients undergoing double-contrast barium enema examinations and 123 patients undergoing esophagographic examinations were included in the study. The study was conducted over a 4-month period, with examinations performed by eight gastrointestinal technologists, 10 radiology residents, and four staff radiologists. Four random lists were generated for each set of examinations. Each staff gastrointestinal radiologist, who was unaware of who had performed the examination, independently scored the representative radiographs. RESULTS: For the double-contrast barium enema examinations, no statistically significant differences were found between the technologists and residents for amount of barium used, degree of distention, cecal opacification, and quality of spot radiographs. The technologist-performed examinations had a statistically significant lower mean fluoroscopy time (3.2 min, compared with 4.0 min for staff radiologists and 5.7 min for residents). For the esophagrams, no statistically significant differences between technologists and residents were found for single-contrast esophagrams; radiographs of the gastric cardia; assessment of motility, reflux, and transit of a solid bolus; and fluoroscopy time. Double-contrast esophagrams obtained by technologists received a better mean score than did those of the residents. CONCLUSION: Radiology technologists can be trained to perform high-quality esophagography and double-contrast barium enema examinations without an unacceptably high radiation dose.


Asunto(s)
Sistema Digestivo/diagnóstico por imagen , Fluoroscopía , Tecnología Radiológica/educación , Adulto , Anciano , Anciano de 80 o más Años , Sulfato de Bario/administración & dosificación , Cardias/diagnóstico por imagen , Ciego/diagnóstico por imagen , Distribución de Chi-Cuadrado , Medios de Contraste/administración & dosificación , Enema , Esófago/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Fluoroscopía/métodos , Fluoroscopía/normas , Reflujo Gastroesofágico/diagnóstico por imagen , Motilidad Gastrointestinal/fisiología , Humanos , Internado y Residencia , Masculino , Persona de Mediana Edad , Intensificación de Imagen Radiográfica , Radiología/educación , Factores de Tiempo
18.
J Clin Invest ; 103(5): 723-9, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10074490

RESUMEN

We have investigated the cellular pathology of the syndrome called thiamine-responsive megaloblastic anemia (TRMA) with diabetes and deafness. Cultured diploid fibroblasts were grown in thiamine-free medium and dialyzed serum. Normal fibroblasts survived indefinitely without supplemental thiamine, whereas patient cells died in 5-14 days (mean 9.5 days), and heterozygous cells survived for more than 30 days. TRMA fibroblasts were rescued from death with 10-30 nM thiamine (in the range of normal plasma thiamine concentrations). Positive terminal deoxynucleotide transferase-mediated dUTP nick end-labeling (TUNEL) staining suggested that cell death was due to apoptosis. We assessed cellular uptake of [3H]thiamine at submicromolar concentrations. Normal fibroblasts exhibited saturable, high-affinity thiamine uptake (Km 400-550 nM; Vmax 11 pmol/min/10(6) cells) in addition to a low-affinity unsaturable component. Mutant cells lacked detectable high-affinity uptake. At 30 nM thiamine, the rate of uptake of thiamine by TRMA fibroblasts was 10-fold less than that of wild-type, and cells from obligate heterozygotes had an intermediate phenotype. Transfection of TRMA fibroblasts with the yeast thiamine transporter gene THI10 prevented cell death when cells were grown in the absence of supplemental thiamine. We therefore propose that the primary abnormality in TRMA is absence of a high-affinity thiamine transporter and that low intracellular thiamine concentrations in the mutant cells cause biochemical abnormalities that lead to apoptotic cell death.


Asunto(s)
Anemia Megaloblástica/patología , Apoptosis , Sordera/patología , Diabetes Mellitus/patología , Fibroblastos/patología , Tiamina/farmacología , Anemia Megaloblástica/genética , Anemia Megaloblástica/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/genética , Proteínas Portadoras/genética , Células Cultivadas , Sordera/genética , Sordera/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Fibroblastos/metabolismo , Humanos , Mutación , Síndrome , Tiamina/genética
19.
JPEN J Parenter Enteral Nutr ; 23(2): 67-74, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10081995

RESUMEN

BACKGROUND: The absence of drug compatibility information with 3-in-1 parenteral nutrition admixtures has been problematic. The purpose of this project was to evaluate the physical compatibility of 106 selected drugs during simulated Y-site injection into nine different 3-in-1 parenteral nutrition admixture formulations. METHODS: Four-milliliter samples of each of the representative 3-in-1 parenteral nutrition admixture formulations were combined in a 1:1 ratio with 4-mL samples of each of 106 drugs, including supportive care drugs, anti-infectives, and antineoplastic drugs. Six replicate samples of each combination were prepared. Two samples were evaluated initially after mixing, two more after 1 hour, and the last two after 4 hours at 23 degrees C. At each test interval, the samples were subjected to centrifugation, causing the fat to rise to the top. The top fat layer and most of the aqueous phase were removed, and the remaining liquid was diluted with about 7 mL of particle-free, high-performance liquid chromatography-grade water to facilitate observation of any particulates that might have formed. Visual examinations were performed in normal diffuse fluorescent laboratory light and under high-intensity, monodirectional light. RESULTS: Most of the drugs tested were physically compatible with the 3-in-1 parenteral nutrition admixtures for 4 hours at 23 degrees C. However, 23 drugs exhibited various incompatibilities with one or more of the parenteral nutrition admixtures. Six drugs resulted in the formation of precipitate with some or all of the admixtures. Seventeen drugs caused disruption of the emulsion, usually with oiling out. CONCLUSIONS: Most of the test drugs were physically compatible with the nine representative 3-in-1 parenteral nutrition admixtures. However, the 23 drugs that resulted in incompatibilities should not be administered simultaneously with the incompatible parenteral nutrition admixtures via a Y injection site.


Asunto(s)
Incompatibilidad de Medicamentos , Nutrición Parenteral , Amicacina/administración & dosificación , Amicacina/química , Aminoácidos/administración & dosificación , Aminoácidos/química , Fenómenos Químicos , Precipitación Química , Química Física , Electrólitos/administración & dosificación , Electrólitos/química , Emulsiones Grasas Intravenosas/administración & dosificación , Emulsiones Grasas Intravenosas/química , Glucosa/administración & dosificación , Glucosa/química , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/química , Soluciones
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