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1.
J Diabetes Metab Disord ; 22(2): 1373-1383, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37975104

RESUMEN

Purpose: This current research study was designed to investigate beneficial effects of R. humilis (Rivina humilis) against streptozotocin-induced diabetic rats. Methods: The R. humilis ethanol extract was prepared using soxhlet and its phenol content was determined. The type-2 diabetes was induced in rats by giving fructose mixed drinking water and single dose of streptozotocin. Oral glucose tolerance test (OGTT) was performed after 72 h of streptozotocin to check ability of extract to utilize oral glucose load with 2 h. The extract was also tested for its potentials to reduce blood glucose (BGL) and diabetic complications by administering to diabetic rats for 21 days. Blood glucose was determined on day 1, 7, 14 and 21. At 21st day, blood samples were collected from experimental rats were euthanized to collect pancreas and liver. Liver and kidney function tests, HbAc1 and lipid profile was established from blood samples. Pancreas was subjected to histopathological examination and liver was used to determine antioxidant enzymes. In vitro study was done to investigate the effect of extract on glucose utilization by rat hemidiaphragm. Results: In OGTT, administration of extract could stimulate glucose utilization which was witnessed by significant BGL reduction at 90 and 120 min in therapeutic groups compare to diabetics. In chronic study, we observed significant reduction in BGL on 21st day and all tests performed to determine liver and kidney function, HbAc1, vitamin E were normal in extract treated groups. There was significant increase in liver antioxidant enzymes in therapeutic groups which revealed regeneration of ß-cells in therapeutic groups. Conclusion: The results of research demonstrated significant antidiabetic potentials in R. humilis. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01258-6.

2.
J Clin Oncol ; 41(14): 2511-2522, 2023 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-36626695

RESUMEN

PURPOSE: To characterize racial and ethnic disparities and trends in opioid access and urine drug screening (UDS) among patients dying of cancer, and to explore potential mechanisms. METHODS: Among 318,549 non-Hispanic White (White), Black, and Hispanic Medicare decedents older than 65 years with poor-prognosis cancers, we examined 2007-2019 trends in opioid prescription fills and potency (morphine milligram equivalents [MMEs] per day [MMEDs]) near the end of life (EOL), defined as 30 days before death or hospice enrollment. We estimated the effects of race and ethnicity on opioid access, controlling for demographic and clinical factors. Models were further adjusted for socioeconomic factors including dual-eligibility status, community-level deprivation, and rurality. We similarly explored disparities in UDS. RESULTS: Between 2007 and 2019, White, Black, and Hispanic decedents experienced steady declines in EOL opioid access and rapid expansion of UDS. Compared with White patients, Black and Hispanic patients were less likely to receive any opioid (Black, -4.3 percentage points, 95% CI, -4.8 to -3.6; Hispanic, -3.6 percentage points, 95% CI, -4.4 to -2.9) and long-acting opioids (Black, -3.1 percentage points, 95% CI, -3.6 to -2.8; Hispanic, -2.2 percentage points, 95% CI, -2.7 to -1.7). They also received lower daily doses (Black, -10.5 MMED, 95% CI, -12.8 to -8.2; Hispanic, -9.1 MMED, 95% CI, -12.1 to -6.1) and lower total doses (Black, -210 MMEs, 95% CI, -293 to -207; Hispanic, -179 MMEs, 95% CI, -217 to -142); Black patients were also more likely to undergo UDS (0.5 percentage points; 95% CI, 0.3 to 0.8). Disparities in EOL opioid access and UDS disproportionately affected Black men. Adjustment for socioeconomic factors did not attenuate the EOL opioid access disparities. CONCLUSION: There are substantial and persistent racial and ethnic inequities in opioid access among older patients dying of cancer, which are not mediated by socioeconomic variables.


Asunto(s)
Analgésicos Opioides , Neoplasias , Masculino , Humanos , Anciano , Estados Unidos/epidemiología , Analgésicos Opioides/uso terapéutico , Evaluación Preclínica de Medicamentos , Medicare , Detección Precoz del Cáncer , Neoplasias/tratamiento farmacológico , Muerte , Pronóstico , Blanco
3.
J Med Chem ; 63(23): 14740-14760, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-33226226

RESUMEN

The discovery of a pan-genotypic hepatitis C virus (HCV) NS3/4A protease inhibitor based on a P1-P3 macrocyclic tripeptide motif is described. The all-carbon tether linking the P1-P3 subsites of 21 is functionalized with alkyl substituents, which are shown to effectively modulate both potency and absorption, distribution, metabolism, and excretion (ADME) properties. The CF3Boc-group that caps the P3 amino moiety was discovered to be an essential contributor to metabolic stability, while positioning a methyl group at the C1 position of the P1' cyclopropyl ring enhanced plasma trough values following oral administration to rats. The C7-fluoro, C6-CD3O substitution pattern of the P2* isoquinoline heterocycle of 21 was essential to securing the targeted potency, pharmacokinetic (PK), and toxicological profiles. The C6-CD3O redirected metabolism away from a problematic pathway, thereby circumventing the time-dependent cytochrome P (CYP) 450 inhibition observed with the C6-CH3O prototype.


Asunto(s)
Antivirales/farmacología , Péptidos Cíclicos/farmacología , Inhibidores de Serina Proteinasa/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Animales , Antivirales/síntesis química , Antivirales/metabolismo , Antivirales/farmacocinética , Células CHO , Cricetulus , Descubrimiento de Drogas , Estabilidad de Medicamentos , Hepacivirus/efectos de los fármacos , Hepacivirus/enzimología , Pruebas de Sensibilidad Microbiana , Microsomas Hepáticos/metabolismo , Estructura Molecular , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/metabolismo , Péptidos Cíclicos/farmacocinética , Ratas , Inhibidores de Serina Proteinasa/síntesis química , Inhibidores de Serina Proteinasa/metabolismo , Inhibidores de Serina Proteinasa/farmacocinética , Relación Estructura-Actividad
4.
Indian J Endocrinol Metab ; 20(5): 631-637, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27730072

RESUMEN

BACKGROUND: Long-term therapy with metformin was shown to decrease the Vitamin B12 level and manifested as peripheral neuropathy. AIM: The aim of this study is to define the prevalence of Vitamin B12 deficiency in early Type 2 diabetic patients (duration ≤5 years or drug treatment ≤3 years) and the relationship among metformin exposure and levels of cobalamin (Cbl), folic acid, and homocysteine (Hcy) with severity of peripheral neuropathy. METHODOLOGY: This is a cross-sectional study involving randomly selected ninety patients (male 56, female 34) between age groups of 35 and 70 years, comparing those who had received >6 months of metformin (Group A) (n = 35) with those without metformin (Group B) (n = 35) and patients taking metformin with other oral hypoglycemic agent (Group C) (n = 20). Comparisons were made clinically, biochemically (serum Cbl, fasting Hcy, and folic acid), and with electrophysiological measures (nerve conduction studies of all four limbs). Comorbidities contributing to neuropathy were excluded from the study. RESULTS: Group A patients (54.28%) were prone to develop peripheral neuropathy comparing Group B (28.57%) and Group C (35%). There was significantly low plasma level of Cbl in Group A (mean 306.314 pg/ml) than in Group B (mean 627.543 pg/ml) and Group C (mean 419.920 pg/ml). There was insignificant low-level plasma folic acid in Group A (16.47 ng/ml) than in Group B (16.81 ng/ml) and Group C (22.50 ng/ml). There was significantly high level of Hcy in Group A (mean 17.35 µmol/L) and Group C (mean 16.99 µmol/L) than in Group B (mean 13.22 µmol/L). Metformin users even for 2 years showed evidence of neuropathy on nerve conduction velocity though their body mass index and postprandial blood sugar were maintained. There was significant difference in between groups regarding plasma Cbl, folic acid, and Hcy level as significance level <0.05 in all three groups (F [2, 87] = 28.1, P = 0.000), (F [2, 87] = 7.43, P = 0.001), (F [2, 87] = 9.76, P = 0.000). Post hoc study shows significant (P < 0.05) lowering of Cbl and Hcy level in Group A (mean = 306.314, standard deviation [SD] = 176.7) than in Group C (mean = 419.92, SD = 208.23) and Group B (mean = 627.543, SD = 168.33). DISCUSSION: Even short-term treatment with metformin causes a decrease in serum Cbl folic acid and increase in Hcy, which leads to peripheral neuropathy in Type 2 diabetes patients. A multicenter study with heterogeneous population would have increased the power of the study. We suggest prophylactic Vitamin B12 and folic acid supplementation or periodical assay in metformin user.

5.
Anal Biochem ; 501: 56-65, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26874021

RESUMEN

Kynurenine aminotransferases convert kynurenine to kynurenic acid and play an important role in the tryptophan degradation pathway. Kynurenic acid levels in brain have been hypothesized to be linked to a number of central nervous system (CNS) disorders. Kynurenine aminotransferase II (KATII) has proven to be a key modulator of kynurenic acid levels in brain and, thus, is an attractive target to treat CNS diseases. A sensitive, high-throughput, label-free RapidFire mass spectrometry assay has been developed for human KATII. Unlike other assays, this method is directly applicable to KATII enzymes from different animal species, which allows us to select proper animal model(s) to evaluate human KATII inhibitors. We also established a coupled fluorescence assay for human KATII. The short assay time and kinetic capability of the fluorescence assay provide a useful tool for orthogonal inhibitor validation and mechanistic studies.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Pruebas de Enzimas/métodos , Inhibidores Enzimáticos/farmacología , Transaminasas/antagonistas & inhibidores , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Enfermedades del Sistema Nervioso Central/tratamiento farmacológico , Enfermedades del Sistema Nervioso Central/enzimología , Inhibidores Enzimáticos/química , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Ácido Quinurénico/metabolismo , Espectrometría de Masas/métodos , Espectrometría de Fluorescencia/métodos , Transaminasas/metabolismo
6.
Nat Prod Commun ; 4(4): 553-6, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19476004

RESUMEN

A water-soluble protein containing glucan was isolated from an edible mushroom, Termitomyces microcarpus (var). It was found to contain 55% of carbohydrate and 40% of protein. The protein part was found to consist of glutamine, arginine, isoleucine, leucine and phenylalanine. The structure of the glucan was analyzed on the basis of total acid hydrolysis, methylation, periodate oxidation and NMR studies (1H, 13C, TOCSY, DQF-COSY, NOESY, and HMQC), and the repeating unit of the glucan is established as: --> 6)-alpha-D-Glcp-(1-->.


Asunto(s)
Glucanos/química , Termitomyces/química , Conformación de Carbohidratos , Glucanos/aislamiento & purificación , Resonancia Magnética Nuclear Biomolecular , Solubilidad
7.
Carbohydr Res ; 343(2): 341-9, 2008 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-18054349

RESUMEN

A water-soluble polysaccharide was isolated from the aqueous extract of the stem of Lagenaria siceraria. The polysaccharide was found to be constituted of methyl d-galacturonate, 2-O-methyl-D-xylose, and d-xylose in a ratio of 1:1:1. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, NMR studies ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, HSQC, and HMBC), and MALDI-TOF MS analysis, the structure of the repeating unit of the polysaccharide is determined as.


Asunto(s)
Plantas/química , Polisacáridos/química , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Extractos Vegetales , Solubilidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Agua
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