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BACKGROUND: The 95-95-95 UNAIDS global strategy was adapted to end the AIDS epidemic by 2030. The target is based on the premise that early detection of HIV-infected persons and linking them to treatment regardless of their CD4 counts will lead to sustained viral suppression. HIV testing strategies to increase uptake of testing in Western and Central Africa remain inadequate. Hence, a high proportion of people living with HIV in this region do not know their status. This report describes the implementation of a community based multi-disease health screening (also known as "Know Your Status" -KYS), as part of basic science research, in a way that contributed to achieving public health goals. METHODS: A community based multi-disease health screening was conducted in 7 communities within the Eastern region of Ghana between November 2017 and April 2018, to recruit and match HIV seronegative persons to HIV seropositive persons in a case-control HIV gut microbiota study. Health assessments included blood pressure, body mass index, blood sugar, Hepatitis B virus, syphilis, and HIV testing for those who consented. HIV seronegative participants who consented were consecutively enrolled in an ongoing HIV gut microbiota case-control study. Descriptive statistics (percentages) were used to analyze data. RESULTS: Out of 738 people screened during the exercise, 700 consented to HIV testing and 23 (3%) were HIV positive. Hepatitis B virus infection was detected in 4% (33/738) and Syphilis in 2% (17/738). Co-infection of HIV and HBV was detected in 4 persons. The HIV prevalence of 3% found in these communities is higher than both the national prevalence of 1.7% and the Eastern Regional prevalence of 2.7 in 2018. CONCLUSION: Community based multi-disease health screening, such as the one undertaken in our study could be critical for identifying HIV infected persons from the community and linking them to care. In the case of HIV, it will greatly contribute to achieving the first two 95s and working towards ending AIDS by 2030.
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Infecciones por VIH , Tamizaje Masivo , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Diagnóstico Precoz , Prevalencia , Continuidad de la Atención al Paciente , Tamizaje Masivo/métodos , Hepatitis B/diagnóstico , Sífilis/diagnóstico , Estudios Transversales , Humanos , Masculino , Femenino , Adulto , Servicios de Salud Comunitaria , Prueba de VIH , Coinfección/epidemiología , Ghana/epidemiologíaRESUMEN
Recent studies have demonstrated that neuromuscular junctions are co-innervated by sympathetic neurons. This co-innervation has been shown to be crucial for neuromuscular junction morphology and functional maintenance. To improve our understanding of how sympathetic innervation affects nerve-muscle synapse homeostasis, we here used in vivo imaging, proteomic, biochemical, and microscopic approaches to compare normal and sympathectomized mouse hindlimb muscles. Live confocal microscopy revealed reduced fiber diameters, enhanced acetylcholine receptor turnover, and increased amounts of endo/lysosomal acetylcholine-receptor-bearing vesicles. Proteomics analysis of sympathectomized skeletal muscles showed that besides massive changes in mitochondrial, sarcomeric, and ribosomal proteins, the relative abundance of vesicular trafficking markers was affected by sympathectomy. Immunofluorescence and Western blot approaches corroborated these findings and, in addition, suggested local upregulation and enrichment of endo/lysosomal progression and autophagy markers, Rab 7 and p62, at the sarcomeric regions of muscle fibers and neuromuscular junctions. In summary, these data give novel insights into the relevance of sympathetic innervation for the homeostasis of muscle and neuromuscular junctions. They are consistent with an upregulation of endocytic and autophagic trafficking at the whole muscle level and at the neuromuscular junction.
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In the original publication of this article [1], the institutional author's name needs to be revised from The Paediatric Chairs of Canada Mark Bernstein to The Paediatric Chairs of Canada.
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Neuromuscular junctions (NMJs) mediate skeletal muscle contractions and play an important role in several neuromuscular disorders when their morphology and function are compromised. However, due to their small size and sparse distribution throughout the comparatively large, inherently opaque muscle tissue the analysis of NMJ morphology has been limited to teased fiber preparations, longitudinal muscle sections, and flat muscles. Consequently, whole mount analyses of NMJ morphology, numbers, their distribution, and assignment to a given muscle fiber have also been impossible to determine in muscle types that are frequently used in experimental paradigms. This impossibility is exacerbated by the lack of optical tissue clearing techniques that are compatible with clear and persistent NMJ stains. Here, we present MYOCLEAR, a novel and highly reproducible muscle tissue clearing protocol. Based on hydrogel-based tissue clearing methods, this protocol permits the labeling and detection of all NMJs in adult hindleg extensor digitorum longus muscles from wildtype and diseased mice. The method is also applicable to adult mouse diaphragm muscles and can be used for different staining agents, including toxins, lectins, antibodies, and nuclear dyes. It will be useful in understanding the distribution, morphological features, and muscle tissue context of NMJs in hindleg muscle whole mounts for biomedical and basic research.
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Vertebrate neuromuscular junctions (NMJs) have been conceived as tripartite synapses composed of motor neuron, Schwann cell, and muscle fiber. Recent work has shown the presence of sympathetic neurons in the immediate vicinity of NMJs and experimental and clinical findings suggest that this plays an eminent role in adult NMJ biology. The present study examined the postnatal development and distribution of sympathetic innervation in different muscles using immunofluorescence, confocal microscopy, and Western blot. This demonstrates the proximity of sympathetic neurons in diaphragm, extensor digitorum longus, tibialis anterior, soleus, and levator auris longus muscles. In extensor digitorum longus muscle, sympathetic innervation of NMJs was quantified from perinatal to adult stage and found to increase up to two months of age. In diaphragm muscle, an extensive network of sympathetic neurons was prominent along the characteristic central synapse band. In summary, these data demonstrate that an elaborate sympathetic innervation is present in several mouse skeletal muscles and that this is often next to NMJs. Although the presence of sympathetic neurons at the perisynaptic region of NMJs increased during postnatal development, many synapses were already close to sympathetic neurons at birth. Potential implications of these findings for treatment of neuromuscular diseases are discussed.
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Músculo Esquelético/inervación , Animales , Ratones , Ratones Endogámicos C57BL , Neuronas Motoras/metabolismo , Neuronas Motoras/fisiología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiología , Músculo Esquelético/metabolismo , Unión Neuromuscular/metabolismo , Unión Neuromuscular/fisiología , Neuropéptido Y/metabolismo , Sinapsis/metabolismo , Sinapsis/fisiología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
BACKGROUND: Pediatrician and pediatric subspecialist density varies substantially among the various Canadian provinces, as well as among various states in the US. It is unknown whether this variability impacts health outcomes. To study this knowledge gap, we evaluated pediatric asthma admission rates within the 2 Canadian provinces of Manitoba and Saskatchewan, which have similarly sized pediatric populations and substantially different physician densities. METHODS: This was a retrospective cross-sectional cohort study. Health regions defined by the provincial governments, have, in turn, been classified into "peer groups" by Statistics Canada, on the basis of common socio-economic characteristics and socio-demographic determinants of health. To study the relationship between the distribution of the pediatric workforce and health outcomes in Canadian children, asthma admission rates within comparable peer group regions in both provinces were examined by combining multiple national and provincial health databases. We generated physician density maps for general practitioners, and general pediatricians practicing in Manitoba and Saskatchewan in 2011. RESULTS: At the provincial level, Manitoba had 48.6 pediatricians/100,000 child population, compared to 23.5/100,000 in Saskatchewan. There were 3.1 pediatric asthma specialists/100,000 child population in Manitoba and 1.4/100,000 in Saskatchewan. Among peer-group A, the differences were even more striking. A significantly higher number of patients were admitted in Saskatchewan (590.3/100,000 children) compared to Manitoba (309.3/100,000, p < 0.0001). CONCLUSIONS: Saskatchewan, which has a lower pediatrician and pediatric asthma specialist supply, had a higher asthma admission rate than Manitoba. Our data suggest that there is an inverse relationship between asthma admissions and pediatrician and asthma specialist supply.
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Asma/terapia , Médicos/provisión & distribución , Especialización , Adolescente , Asma/epidemiología , Niño , Preescolar , Estudios Transversales , Bases de Datos Factuales , Odontólogos/provisión & distribución , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Manitoba/epidemiología , Pediatras/provisión & distribución , Estudios Retrospectivos , Saskatchewan/epidemiología , Resultado del TratamientoRESUMEN
OBJECTIVE: To determine if the effects of using the Steps to Freedom would be beneficial for a group of individuals who attended a Christian Conference. METHODS: A user-friendly 12-item questionnaire was used to monitor the outcomes of Steps to Freedom addressing six symptom/behavioral problems and six function areas. In addition, the Symptom Checklist-90 R (SCL-90-R) questionnaire was employed to document the validity of the shorter questionnaire. The questionnaires were completed before and after the administration of the Steps to Freedom. The Wilcoxon matched pairs test was used to measure the significance of the findings for the 12-item questionnaire. RESULTS: Thirty-three clients who went through the Steps to Freedom showed statistically significant improvement (P < or = 0.005) at 3 to 4 months in all symptom/behavior categories (items 1-6). All function areas (items 7-12) also demonstrated statistically significant improvement (P < or = 0.05). A comparison group who did not attend the conference or receive counseling showed no significant changes during the same period. CONCLUSIONS: These significant preliminary findings need to be confirmed by additional studies. Steps to Freedom model prayers, used by individual patients personally and/or with a counselor, could expand the care and hopefully lower the cost of mental illness.
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Curación por la Fe/métodos , Trastornos Mentales/terapia , Adulto , Ansiedad/terapia , Estudios de Casos y Controles , Consejo , Depresión/terapia , Femenino , Humanos , MasculinoRESUMEN
Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM) are promising cancer chemopreventive agents in rodent models, but there is a paucity of data on their pharmacokinetics and tissue disposition. The disposition of I3C and its acid condensation products, DIM, [2-(indol-3-ylmethyl)-indol-3-yl]indol-3-ylmethane (LTr(1)), indolo[3,2b]carbazole (ICZ) and 1-(3-hydroxymethyl)-indolyl-3-indolylmethane (HI-IM) was studied, after oral administration of I3C (250 mg/kg) to female CD-1 mice. Blood, liver, kidney, lung, heart, and brain were collected between 0.25 and 24 h after administration and the plasma and tissue concentrations of I3C and its derivatives determined by high-performance liquid chromotography. I3C was rapidly absorbed, distributed, and eliminated from plasma and tissues, falling below the limit of detection by 1 h. Highest concentrations of I3C were detected in the liver where levels were approximately 6-fold higher than those in the plasma. Levels of DIM, LTr(1), and HI-IM were much lower, although they persisted in plasma and tissues for considerably longer. DIM and HI-IM were still present in the liver 24 h after I3C administration. Tissue levels of DIM and LTr(1) were found to be in equilibrium with plasma at almost every time point measured. In addition to acid condensation products of I3C, a major oxidative metabolite (indole-3-carboxylic acid) and a minor oxidative metabolite (indole-3-carboxaldehyde) were detected in plasma of mice after oral administration of I3C. ICZ was also tentatively identified in the liver of these mice. This study shows for the first time that, after oral administration to mice, I3C, in addition to its acid condensation products, is absorbed from the gut and distributed systemically into a number of well-perfused tissues, thus allowing the possibility for some pharmacological activity of the parent compound in vivo.
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Anticarcinógenos/administración & dosificación , Anticarcinógenos/farmacocinética , Indoles/administración & dosificación , Indoles/farmacocinética , Administración Oral , Animales , Anticarcinógenos/sangre , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Femenino , Depuradores de Radicales Libres/administración & dosificación , Depuradores de Radicales Libres/sangre , Depuradores de Radicales Libres/farmacocinética , Indoles/sangre , Hígado/metabolismo , Ratones , Modelos Químicos , Oxígeno/metabolismo , Perfusión , Factores de Tiempo , Distribución TisularRESUMEN
The effect of protein calorie malnutrition (PCM) on the pharmacokinetics of ketamine (KET) enantiomers has been investigated. Six control and six PCM rats were administered 85 mg/kg racemic KET by intramuscular injection, and plasma concentrations of (S)- and (R)-KET, norketamine (NKET), and 5,6-dehydronorketamine (DNK) were measured using enantioselective gas chromatography. Pharmacokinetic profiles were analyzed using standard noncompartmental and compartmental modeling methods. The volumes of distribution were similar between control and PCM rats for (S)- and (R)-KET. However, total clearance of both KET enantiomers was decreased, resulting in an increase in systemic exposure (p < 0.05). The KET absorption rate was also increased in PCM rats. A decrease in the clearance of both NKET enantiomers led to a significant increase in exposure in PCM rats (p < 0.005), and modeling results could not exclude the possibility that PCM induced an increase in the fraction of KET following the NKET pathway, which may further contribute to this increase in exposure. An increase in exposure to DNK enantiomers was also evident in PCM animals compared with controls [p < 0.005 (DNK1); N.S. (DNK2)], which was in concordance with the decrease in apparent clearance values. These results show that PCM significantly alters the pharmacokinetics of KET and several of its metabolites.
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Ketamina/sangre , Ketamina/farmacocinética , Desnutrición Proteico-Calórica/metabolismo , Animales , Masculino , Desnutrición Proteico-Calórica/sangre , Ratas , Ratas Sprague-DawleyRESUMEN
3,3'-Diindolylmethane (DIM) is a naturally occurring indole, which is currently under investigation as a potential chemopreventive agent. The concentrations of DIM in plasma, liver, kidney, lung, heart, and brain tissues were determined following oral administration of two different formulations to mice (250 mg/kg). Mice were sacrificed periodically from 0 to 24 h after administration of either a crystalline or an absorption-enhanced formulation (Bio-Response-DIM; Indolplex) of DIM, and plasma and tissue concentrations were determined by high-performance liquid chromatography (UV detection, 280 nm). A physiologically based pharmacokinetic (PBPK) model was developed to characterize the pharmacokinetic properties of the two different formulations. The final model included parameters reflecting linear first-order absorption, systemic clearance, and distributional clearance in the remainder compartment, which were considered independent of formulation. All pharmacokinetic profiles from the two formulations were fitted simultaneously to estimate unknown model parameters. Plasma and tissue concentration-time profiles exhibited a rapid rise to peak values at 0.5 to 1 h, followed by a polyexponential decline with an extended terminal phase. These profiles were well described by the final model and unknown parameters were estimated with relatively low coefficients of variation. Relative drug exposure and absorption parameters suggest that BioResponse-DIM exhibited approximately 50% higher bioavailability than the crystalline formulation. Clearance of DIM was estimated as 7.18 ml/h. This is the first study to characterize the pharmacokinetics of DIM in mice, and the established PBPK model should prove useful in the design and analysis of future preclinical studies aimed at evaluating the in vivo pharmacological effects of DIM.
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Anticarcinógenos/farmacocinética , Indoles/farmacocinética , Administración Oral , Animales , Anticarcinógenos/sangre , Área Bajo la Curva , Química Farmacéutica , Cromatografía Liquida , Femenino , Indoles/sangre , Ratones , Ratones Endogámicos , Modelos Biológicos , Distribución TisularRESUMEN
The release of asbestos during maintenance and removal of resilient floor covering is of concern to health professionals and many regulators. This study assesses the asbestos levels observed during removal of resilient floor covering products using the "Recommended Work Practices" (1995) of the Resilient Floor Covering Institute or other methods requiring containment (Controls). The 1995 "work practices" require wet removal or dry heat removal but do not require the use of respirators. Wet removals of sheet vinyl/separated backing, 12" x 12" vinyl asbestos tile/mastic, and 9" x 9" asphalt tiles/mastic were conducted and the air was sampled during each procedure. Settled dust samples were collected at the sites of RFCI square tile removal and pieces of each type of tile were broken in a mini-enclosure to evaluate asbestos emissions. Analyses of the air samples collected during the removals showed that the RFCI methods did not produce asbestos counts significantly different from the Control methods requiring containment. Only a small number (0.7%) of fibers and structures, counted and measured by Analytical Transmission Electron Microscopy, would have been counted using the rules for Phase Contrast Microscopy in the 7400 method specified by Occupational Safety and Health Administration regulations. This indicates workers in similar situations without respirators are likely to have unknown exposure levels. A high percentage of these fibers and structures are 5 micrometers or less in length, smaller than 0.5 micrometer in diameter, and are easily inhaled. The RFCI air sample and settled dust data may cause regulators to consider requiring respiratory protection, cleanup procedures, and methods to control asbestos migration. Other areas that might be addressed are clearance levels and their measurement, removal area size, bulk sample analysis by transmission electron microscopy if polarized light microscopy reports less than 1 percent asbestos, better worker exposure evaluation, and supervisor/worker training in accordance with the Model Accreditation Plan.
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Contaminantes Ocupacionales del Aire/análisis , Amianto/análisis , Monitoreo del Ambiente/métodos , Pisos y Cubiertas de Piso , Fibras Minerales/análisis , Monitoreo del Ambiente/normas , Humanos , Microscopía Electrónica de Transmisión de Rastreo , Microscopía de Contraste de Fase , Estados UnidosRESUMEN
A high-performance liquid chromatographic method was developed for the simultaneous determination of indole-3-carbinol (I3C), 3,3'-diindolylmethane (DIM), [2-(indol-3-ylmethyl)-indol-3-yl]indol-3-ylmethane (LTr(1)), and indolo[3,2b]carbazole (ICZ). Compounds were extracted from mouse plasma using tert.-butyl methyl ether, incorporating 4-methoxy-indole as internal standard. Chromatographic separation utilized a Waters Symmetry RP18 in tandem with a Thermoquest BDS C(18) column, an acetonitrile-water gradient and UV (280 nm) in series with fluorescence (ex. 335 nm; em. 415 nm) detection. Calibration curves were linear (r(2)>0.99) between 50 and 15,000 ng/ml for I3C; 150 and 15,000 ng/ml for LTr(1); and 0.15 and 37.5 ng/ml for ICZ and the method was reproducible and precise (within-day and between-day coefficients of variation below 9.7 and 13%, respectively). The method described is suitable for comprehensive pharmacokinetic studies with indole-3-carbinol.
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Cromatografía Líquida de Alta Presión/métodos , Indoles/sangre , Calibración , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría UltravioletaRESUMEN
Asbestos has been used in many applications, but possibly one of the more unique was in the manufacturing of filters for cigarettes. The type of asbestos used in this application was crocidolite. Data from several resources indicate that crocidolite was one of the least utilized types of commercial asbestos in the United States. The present study provides quantitative tissue burden analysis data for two mesothelioma cases where the work histories included manufacturing of cigarette filters that contained crocidolite. The data include the number of asbestos bodies and uncoated fibers per gram of tissue, as well as the dimensions of these structures. The conclusion of the findings indicates that the individuals had an appreciable homogeneous exposure to crocidolite asbestos.
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Asbesto Crocidolita/efectos adversos , Mesotelioma/etiología , Neoplasias Pleurales/etiología , Industria del Tabaco , Anciano , Resultado Fatal , Humanos , Masculino , Mesotelioma/patología , Exposición Profesional , Neoplasias Pleurales/patologíaRESUMEN
Curcumin, the major yellow pigment in turmeric, prevents the development of adenomas in the intestinal tract of the C57Bl/6J Min/+ mouse, a model of human familial APC. To aid the rational development of curcumin as a colorectal cancer-preventive agent, we explored the link between its chemopreventive potency in the Min/+ mouse and levels of drug and metabolites in target tissue and plasma. Mice received dietary curcumin for 15 weeks, after which adenomas were enumerated. Levels of curcumin and metabolites were determined by high-performance liquid chromatography in plasma, tissues, and feces of mice after either long-term ingestion of dietary curcumin or a single dose of [(14)C]curcumin (100 mg/kg) via the i.p. route. Whereas curcumin at 0.1% in the diet was without effect, at 0.2 and 0.5%, it reduced adenoma multiplicity by 39 and 40%, respectively, compared with untreated mice. Hematocrit values in untreated Min/+ mice were drastically reduced compared with those in wild-type C57Bl/6J mice. Dietary curcumin partially restored the suppressed hematocrit. Traces of curcumin were detected in the plasma. Its concentration in the small intestinal mucosa, between 39 and 240 nmol/g of tissue, reflects differences in dietary concentration. [(14)C]Curcumin disappeared rapidly from tissues and plasma within 2-8 h after dosing. Curcumin may be useful in the chemoprevention of human intestinal malignancies related to Apc mutations. The comparison of dose, resulting curcumin levels in the intestinal tract, and chemopreventive potency suggests tentatively that a daily dose of 1.6 g of curcumin is required for efficacy in humans. A clear advantage of curcumin over nonsteroidal anti-inflammatory drugs is its ability to decrease intestinal bleeding linked to adenoma maturation.
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Adenoma/prevención & control , Poliposis Adenomatosa del Colon/prevención & control , Antineoplásicos/farmacología , Antineoplásicos/farmacocinética , Neoplasias del Colon/prevención & control , Curcumina/farmacología , Curcumina/farmacocinética , Predisposición Genética a la Enfermedad , Poliposis Adenomatosa del Colon/veterinaria , Administración Oral , Animales , Modelos Animales de Enfermedad , Hemorragia Gastrointestinal/prevención & control , Genes APC , Hematócrito , Masculino , Ratones , Ratones Endogámicos C57BL , Mutación Puntual , Distribución TisularRESUMEN
Advances in chiral chromatographic separations have given pharmacologists and toxicologists the tools to examine unexpected clinical results involving chiral drugs. The ability to unravel complex phenomena associated with drug transport and drug metabolism is presented in this manuscript. The relation between the chirality of the drug mefloquine and the intracellular concentrations of the drug cyclosporine is illustrated by examining the effect of the enantiomers of mefloquine on the transport activity of P-glycoprotein (Pgp). These studies were conducted using a liquid chromatographic column containing immobilized Pgp. The results demonstrated that (+)-mefloquine competitively displaced the Pgp substrate cyclosporine whereas (-)-mefloquine had no effect on cyclosporine-Pgp binding. The data suggest that cyclosporine cellular and CNS concentrations can be increased through the concomitant administration of (+)-mefloquine. The use of chirality in clinical and forensic situations is also illustrated by the metabolism of the enantiomers of ketamine (KET). The plasma concentrations of (+)-KET and (-)-KET and the norketamine metabolites (+)-NK and (-)-NK were measured in rat plasma using enantioselective gas chromatography. The separations were accomplished using a gas chromatography chiral stationary phase based on beta-cyclodextrin. The pharmacokinetic profiles of (+)-, (-)-KET and (+)-, (-)-NK were determined in control and protein-calorie malnourished (PCM) rats to determine the effect of PCM on ketamine metabolism and clearance. The results indicate that PCM produced a significant and stereoselective decrease in KET and NK metabolism. The data suggest that the effects of environmental factors (smoking, alcohol use, diet) and drug interactions (coadministered agents) can be measured using the changes in stereochemical metabolic and pharmacokinetic patterns of KET and similar drugs.
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Cromatografía de Gases/métodos , Monitoreo de Drogas/métodos , Medicina Legal/métodos , Toxicología/métodos , Ciclosporina/análisis , Ciclosporina/química , Humanos , Isomerismo , Ketamina/análisis , Ketamina/química , Mefloquina/análisis , Mefloquina/químicaRESUMEN
The effect of disease state on drug metabolism has been investigated using the relationship between genotype and metabolic phenotype. The two polymorphic probes, N-acetyltransferases-2 (NAT2) and cytochrome P450 2C19 (CYP2C19), were respectively used in HIV+/AIDS patients and patients with advanced cancer. The results of the studies suggest that advanced disease produces discordances between genotype and phenotype, indicating a reduction in the metabolic capabilities of these individuals. Thus, polymorphic enzymes such as CYP2C19 and NAT2 can be used to probe changes in drug-metabolizing enzyme capacities. The development of genotype/phenotype discordances should reflect general changes in metabolic capabilities and, thus, alterations in the activities of other important enzymes such as CYP3A. The data also suggest that the genotype/phenotype probes can be used to optimize the clinical treatment of patients with advanced disease states.
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Progresión de la Enfermedad , Genotipo , Preparaciones Farmacéuticas/metabolismo , Fenotipo , Animales , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismoRESUMEN
Curcumin, the yellow pigment in turmeric, prevents malignancies in the intestinal tract of rodents. It is under clinical evaluation as a potential colon cancer chemopreventive agent. The systemic bioavailability of curcumin is low, perhaps attributable, at least in part, to metabolism. Indirect evidence suggests that curcumin is metabolized in the intestinal tract. To investigate this notion further, we explored curcumin metabolism in subcellular fractions of human and rat intestinal tissue, compared it with metabolism in the corresponding hepatic fractions, and studied curcumin metabolism in situ in intact rat intestinal sacs. Analysis by high-performance liquid chromatography, with detection at 420 or 280 nm, permitted characterization of curcumin conjugates and reduction products. Chromatographic inferences were corroborated by mass spectrometry. Curcumin glucuronide was identified in intestinal and hepatic microsomes, and curcumin sulfate, tetrahydrocurcumin, and hexahydrocurcumin were found as curcumin metabolites in intestinal and hepatic cytosol from humans and rats. The extent of curcumin conjugation was much greater in intestinal fractions from humans than in those from rats, whereas curcumin conjugation was less extensive in hepatic fractions from humans than in those from rats. The curcumin-reducing ability of cytosol from human intestinal and liver tissue exceeded that observed with the corresponding rat tissue by factors of 18 and 5, respectively. Curcumin sulfate was identified in incubations of curcumin with intact rat gut sacs. Curcumin was sulfated by human phenol sulfotransferase isoenzymes SULT1A1 and SULT1A3. Equine alcohol dehydrogenase catalyzed the reduction of curcumin to hexahydrocurcumin. The results show that curcumin undergoes extensive metabolic conjugation and reduction in the gastrointestinal tract and that there is more metabolism in human than in rat intestinal tissue. The pharmacological implications of the intestinal metabolism of curcumin should be taken into account in the design of future chemoprevention trials of this dietary constituent.