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1.
Front Public Health ; 10: 858402, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903375

RESUMEN

The number of immigrants seeking entry into the U.S. through asylum requests or through irregular means is increasing, and most come from the Northern Triangle of El Salvador, Guatemala, and Honduras. Immigrants come fleeing extreme poverty, violence, health and social inequities, and drastic climate changes. Most had limited access to healthcare at home, and even more limited care along the journey. Those that are allowed entry into the U.S., are confronted with feeling unwelcome in many communities, having to navigate an array of local, state, and federal laws that regulate access to healthcare. We need immigration policies that preserve the health, dignity with a multinational policy for provision of healthcare through a human rights lens from point of origin to point of destination.


Asunto(s)
Emigrantes e Inmigrantes , Derechos Humanos , Atención a la Salud , Guatemala , Humanos , México
2.
Toxins (Basel) ; 13(9)2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34564668

RESUMEN

Glutathione S-transferases are a family of detoxifying enzymes that catalyze the conjugation of reduced glutathione (GSH) with different xenobiotic compounds using either Ser, Tyr, or Cys as a primary catalytic residue. We identified a novel GST in the genome of the shrimp pathogen V. parahaemolyticus FIM- S1708+, a bacterial strain associated with Acute Hepatopancreatic Necrosis Disease (AHPND)/Early Mortality Syndrome (EMS) in cultured shrimp. This new GST class was named Gtt2. It has an atypical catalytic mechanism in which a water molecule instead of Ser, Tyr, or Cys activates the sulfhydryl group of GSH. The biochemical properties of Gtt2 from Vibrio parahaemolyticus (VpGSTT2) were characterized using kinetic and crystallographic methods. Recombinant VpGSTT2 was enzymatically active using GSH and CDNB as substrates, with a specific activity of 5.7 units/mg. Low affinity for substrates was demonstrated using both Michaelis-Menten kinetics and isothermal titration calorimetry. The crystal structure showed a canonical two-domain structure comprising a glutathione binding G-domain and a hydrophobic ligand H domain. A water molecule was hydrogen-bonded to residues Thr9 and Ser 11, as reported for the yeast Gtt2, suggesting a primary role in the reaction. Molecular docking showed that GSH could bind at the G-site in the vicinity of Ser11. G-site mutationsT9A and S11A were analyzed. S11A retained 30% activity, while T9A/S11A showed no detectable activity. VpGSTT2 was the first bacterial Gtt2 characterized, in which residues Ser11 and Thr9 coordinated a water molecule as part of a catalytic mechanism that was characteristic of yeast GTT2. The GTT2 family has been shown to provide protection against metal toxicity; in some cases, excess heavy metals appear in shrimp ponds presenting AHPND/EMS. Further studies may address whether GTT2 in V. parahaemolyticus pathogenic strains may provide a competitive advantage as a novel detoxification mechanism.


Asunto(s)
Glutatión Transferasa/genética , Penaeidae/microbiología , Vibrio parahaemolyticus/genética , Animales , Genoma , Filogenia , Análisis de Secuencia
3.
Molecules ; 24(19)2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31581425

RESUMEN

The Cu2+, Mn2+, and Fe3+ complexes of a 14 membered macrocycle were synthesized and their antioxidant capacities were evaluated against ABTS and DPPH radicals, with the objective of collecting insights into the biomimetic role of the central metal ions. The macrocycle, abbreviated as H2L14, is a derivative of EDTA cyclized with 1,4-diamine, and the moderately flexible macrocyclic frame permits the formation of [ML14·H2O] chelates with octahedral coordination geometries common among the metal ions. The metal complexes were characterized by electrospray-ionization mass spectrometry, Fourier transform infrared spectroscopy, and Raman and X-ray photoelectron spectroscopic methods, as well as thermogravimetric analysis; the octahedral coordination geometries with water coordination were optimized by DFT calculations. The antioxidant assays showed that [FeL14·H2O]+ was able to scavenge synthetic radicals with moderate capacity, whereas the other metal chelates did not show significant activity. The Raman spectrum of DPPH in solution suggests that interaction was operative between the Fe3+ chelate and the radical so as to cause scavenging capability. The nature of the central metal ions is a controlling factor for antioxidant capacity, as every metal chelate carries the same coordination geometry.


Asunto(s)
Antioxidantes/síntesis química , Complejos de Coordinación/síntesis química , Ácido Edético/química , Compuestos Macrocíclicos/síntesis química , Antioxidantes/química , Complejos de Coordinación/química , Cobre/química , Teoría Funcional de la Densidad , Hierro/química , Compuestos Macrocíclicos/química , Manganeso/química , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
4.
ACS Omega ; 4(27): 22487-22496, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31909331

RESUMEN

With the objective of studying the conformational and macrocyclic effects of selected metal chelates on their peroxidase activities, Cu2+ and Fe3+ complexes were synthesized with a macrocyclic derivative of ethylenediaminetetraacetic acid and o-phenylenediamine (abbreviated as edtaodH2) and its new open-chain analogue (edtabzH2). The Fe3+ complex of edtaodH2 has a peroxidase-like activity, whereas the complex of edtabzH2 does not. The X-ray study of the former shows the formation of a dimeric molecule {[Fe(edtaod)]2O} in which each metal with an octahedral coordination is overposed over the macrocyclic cavity, as a result of rigid macrocyclic frame, to form an Fe-O-Fe bridge; the exposure of the central metal to the environment facilitates the capture of oxygen to drive the biomimetic activity. The peroxidase-inactive Fe3+ complex consists of a mononuclear complex ion [Fe(edtabz)(H2O)]+, the metal ion of which is suited in a distorted pentagonal bipyramid to be protected from environmental oxygen. The copper(II) complexes, which have mononuclear structures with high thermodynamic stability compared with the iron(III) complexes, show no peroxidase activity. The steric effects play a fundamental role in the biomimetic activity.

5.
Subst Use Misuse ; 49(8): 941-54, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24779493

RESUMEN

Drug use among older adults is a growing concern, particularly for the burgeoning Hispanic population. Older adults seeking drug treatment will double over the next decade to almost 6 million. Cultural factors influence drug use, and more specifically, Hispanic cultural values influence heroin use. This study explored Mexican-American injection drug users' adherence to traditional Hispanic cultural values and their impact on cessation. Ethnographic interviews endorsed contextualized influences of values on heroin use. Cultural values functioned dichotomously, influencing both initiation and cessation. Understanding the impact of cultural values on substance abuse is critical given the changing demographics in American society.


Asunto(s)
Cultura , Dependencia de Heroína/etnología , Americanos Mexicanos/psicología , Abuso de Sustancias por Vía Intravenosa/etnología , Síndrome de Abstinencia a Sustancias/etnología , Anciano , Anciano de 80 o más Años , Dependencia de Heroína/rehabilitación , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Factores de Riesgo , Abuso de Sustancias por Vía Intravenosa/rehabilitación , Síndrome de Abstinencia a Sustancias/prevención & control , Encuestas y Cuestionarios , Texas
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