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1.
Artigo em Inglês | MEDLINE | ID: mdl-33478176

RESUMO

In the Gulf of California; mineral deposits have contributed to high metal contents in coastal environments. This study examined cadmium; lead; copper; zinc; and iron contents in three fish species; Kyphosus vaigiensis (herbivore), Stegastes rectifraenum (omnivore), and Balistes polylepis (carnivore) at two mining sites. Metal concentrations were analyzed by atomic absorption spectrophotometry and stable nitrogen and carbon isotopes were estimated using mass spectrophotometry. Also, we assessed the risk to human health from the consumption of these three species based on permissible limits; although only two of them (Kyphosus and Balistes) are consumed as food. Metal concentrations differed among fish species; except for iron. The highest concentrations of metals were not always recorded in the species at the highest trophic level; i.e., Balistes. The highest concentrations (dry weight) recorded were cadmium (0.21 ± 0.03 µg g-1) and lead (1.67 ± 0.26 µg g-1), in S. rectifraenum; copper (1.60 ± 0.49 µg g-1) and zinc (67.30 ± 8.79 µg g-1), in B. polylepis; and iron (27.06 ± 2.58 µg g-1), in K. vaigiensis. Our findings show that each element accumulates differently in particular marine organisms; depending on the physiology of the species and the biogeochemistry of its habitat; which in turn is affected by the anthropogenic activities in adjacent areas. No risk of heavy metals toxicity is expected from the human consumption of the species and sites studied.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31654830

RESUMO

Cadmium (Cd) occurs naturally; however, its concentration can increase with anthropogenic activities. Excess Cd increases reactive oxygen species (ROS) production and oxidative damage, which can lead to pathological conditions. Marine mammals accumulate Cd in the liver and the kidney; yet, there are no reports of Cd-associated tissue damage in whales, seals or dolphins. Response to Cd exposure (0-5.0 µM CdCl2 for 1-12 h) was analyzed and compared in primary skeletal muscle cells isolated from northern elephant seals (Mirounga angustirostris) and humans (Homo sapiens). Antioxidant enzyme activities (glutathione S-transferase, glutathione reductase, glutathione peroxidase), glutathione concentration, and protein carbonyl levels (an indicator of oxidative damage) were quantified. Glutathione levels were higher in northern elephant seal than in human cells. Protein carbonyl content in cells exposed to Cd was lower and had a smaller variability range in elephant seals than in humans. Generalized linear models (GLIM) identified Cd exposure and antioxidant defenses as significant contributors to protein carbonyl variability in human but not in elephant seal cells. These results suggest that the previously observed differences in circulating and tissue glutathione levels between marine and terrestrial mammals are maintained under cell culture conditions and that northern elephant seal and human muscle cells respond differently to Cd exposure. The results also suggest that the observed differences could potentially be associated with the protective mechanisms that allow northern elephant seals to tolerate extreme conditions that result in increased ROS generation (e.g. diving, sleep apnea, fasting) with no oxidative damage.


Assuntos
Cádmio/toxicidade , Fibras Musculares Esqueléticas/efeitos dos fármacos , Músculo Esquelético/citologia , Focas Verdadeiras/fisiologia , Animais , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Carbonilação Proteica
3.
Chemosphere ; 234: 702-714, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31234087

RESUMO

INTRODUCTION: Previous studies of mercury (Hg) in pregnant women in the area of La Paz, Baja California Sur (BCS), Mexico found a proportion of individuals had concentrations of total Hg ([THg]) above some thresholds of concern set by health agencies. The [THg] were associated with fish and seafood consumption as well as other factors; although it was unclear which marine diet items could potentially be contributing to the concentrations observed. METHOD: We examined [THg] and monomethylmercury concentration ([MeHg+]) in the archived hair of 70 pregnant women from BCS as well as in diet items including fish, shellfish, and staple items (rice, beans, corn, and flour). We measured stable isotopes of carbon and nitrogen and employed a Bayesian stable isotope mixing model to investigate the proportion of fish and seafood in the isotopic profiles of archived hair samples. RESULTS: Concentrations of Hg species were low in staple foods and ranged from below detection limit to 5.71 parts per billion (ppb) wet weight. In hair, geometric mean [THg] was 658 ppb and [MeHg+] was 395 ppb, which were lower than previous reports. Percent MeHg+ was positively correlated with higher δ15N values. CONCLUSIONS: The largest carbon contributors to the diet of the study participants were corn and rice, and our analysis of fish contribution to diet varyingly agreed with the self-reported fish consumption. This report highlights the ability to discriminate potential sources of Hg from a diverse diet and the limitations of dietary recall studies.


Assuntos
Carbono/análise , Peixes/metabolismo , Cabelo/química , Mercúrio/análise , Isótopos de Nitrogênio/análise , Nitrogênio/análise , Alimentos Marinhos/análise , Adolescente , Adulto , Animais , Teorema de Bayes , Dieta , Feminino , Humanos , México , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
4.
J Trace Elem Med Biol ; 51: 36-41, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30466936

RESUMO

Breast milk contains micronutrients that function as cofactors of antioxidant enzymes. High concentrations of iron (Fe) and copper (Cu) can increase the production of reactive oxygen species (ROS). This study aimed to assess the relationship between the activity of antioxidant enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST)) and the concentration of the micronutrients Fe, Cu and zinc (Zn) in breast milk. Breast milk samples were collected from 108 mothers (7-10 days postpartum, transitional milk). The samples were grouped into three groups according to the number of pregnancies (one, two and three or more pregnancies), also grouped according to the body mass index (BMI) suggested by the World Health Organization (WHO) in underweight, normal weight, overweight and obese. Breast milk Fe, Cu and Zn concentrations were determined by atomic absorption spectrophotometry and the activity of the antioxidant enzymes was determined by spectrophotometry. An increase in GPx, SOD and GST activities in relation to the number of pregnancies was found (p = 0.05, p = 0.04 and p < 0.01, respectively). An inverse relationship between GST activity and BMI was found (p = 0.05). A positive correlation was observed between Cu and Zn concentrations (r = 0.52, p < 0.05). A negative correlation was found between Cu concentration and catalase activity (r = -0.22, p < 0.05); Fe content was negatively correlated with GPx and GST activities (r = -0.32, r = -0.22, respectively, p < 0.05). The activities of antioxidant enzymes (GPx, SOD and GST) may be affected by the number of pregnancies and contribute to prevent oxidation of nutritional molecules in breast milk.


Assuntos
Antioxidantes/metabolismo , Micronutrientes/análise , Leite Humano/química , Leite Humano/enzimologia , Adolescente , Adulto , Catalase/metabolismo , Cobre/análise , Feminino , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Humanos , Ferro/análise , Superóxido Dismutase/metabolismo , Adulto Jovem , Zinco/análise
5.
J Ethnopharmacol ; 225: 159-168, 2018 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-29990521

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The medicinal plant Sedum oxypetalum Kunth (Crassulaceae), locally known as Jiote or in general Siempreviva (always alive) has been traditionally used by people of the Mexican community of Tenango del Valle as a home remedy to treat periodontal diseases, inducing teeth strengthening. Consequently, the aim of this work was to investigate its capacity directed to mineralized tissues regeneration. MATERIALS AND METHODS: The aerial parts of the plant were processed and its aqueous extract (AE) was chemically characterized. The AE and its components sedoheptulose and syngenite were tested for either osteogenic differentiation or mineral-nucleation induction respectively. RESULTS: The AE and one of its components (sedoheptulose) were shown to promote the proliferation and/or osteogenic differentiation by Human Periodontal Ligament-Derived Cells (hPDLs), while inducing the mineralization process. The AE also promoted the nucleation of octacalcium phosphate and its component syngenite, the hydroxyapatite crystals formation in vitro. CONCLUSION: The findings reported herein support the traditional use of S. oxypetalum due to its potential capacity to promote the regeneration of mineralized tissues.


Assuntos
Ligamento Periodontal/citologia , Extratos Vegetais/farmacologia , Sedum , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Osteogênese , Extratos Vegetais/análise , Sulfatos/análise , Sulfatos/farmacologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-29498700

RESUMO

The mining activity in the San Antonio-El Triunfo district, located in a mountainous region at 60 km southeast of La Paz, occured for more than 250 years and left behind severe contamination of soils and riverbed sediments which led to elevated concentrations of arsenic and other trace elements in the surface- and groundwater of the region. Although the main mining activity ended around 1911, contamination is still beeing distributed, especially from left behind tailings and mine waste piles. The contamination levels in the groundwater have been reported in several studies, but there is little information available on the surface water quality, and especially the temporal variation. In this study, we analyzed the surface water of the La Junta creek, in the southern part of the San Antonio-El Triunfo mining district. The working hypothesis was that by means of a spatial analysis of surface water and shallow groundwater, in combination with the temporal observation of the concentrations in runoff water, the effects of different sources of arsenic (natural geogene anomalies, due to historic mining activity, and hydrothermal related impact) in the La Junta creek can be recognized. This present study revealed that historic mining activity caused a mojor impact of arsenic but less contamination was observed than in the northern part of the district and elevated arsenic concentrations in stream water generally occurred during times of low streamflow.


Assuntos
Arsênico/análise , Monitoramento Ambiental , Mineração , Rios/química , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , México
7.
Rev. Col. Méd. Cir. Guatem ; 156(1): 47-50, 2017 jul. ilus
Artigo em Espanhol | LILACS | ID: biblio-982135

RESUMO

La mordedura por araña del género Loxosceles produce dermonecrosis en el sitio de la lesión y complicaciones sistémicas secundarias a reacciones enzimáticas de su veneno, lo que aumenta la tasa de mortalidad. El objetivo es reportar cuatro casos de loxoscelismo atendidos en el hospital General San Juan de Dios, donde los pacientes tuvieron una evolución satisfactoria a pesar de la inexistencia del antiveneno como manejo ideal de la toxicidad (AU)


Assuntos
Humanos , Feminino , Picaduras de Aranhas/tratamento farmacológico , Venenos de Aranha/efeitos adversos , Aranha Marrom Reclusa/patogenicidade , Hemólise , Guatemala
8.
Nutr Hosp ; 34(1): 59-64, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28244773

RESUMO

INTRODUCTION: Breast milk contains molecules needed for the development of children; the integrity and function of these molecules is affected by the presence of pro-oxidants. Protein carbonyls are mainly produced as a result of the interaction of metals with reactive oxygen species (ROS), which may initiate a chain reaction that promotes molecular oxidation. OBJECTIVE: This study aimed to determine the association between the concentration of protein carbonyls with the concentration of trace elements (lead [Pb], cadmium [Cd] and selenium [Se]), superoxide radical (O2•-) production, and glutathione (GSH) content, as well with the activity of the main antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], glutathione reductase [GR] and glutathione S-transferase [GST]) in breast milk. METHODS: In this study 108 transitional milk samples (7-10 days) were analyzed. Antioxidant enzyme activities, O2•-production, protein carbonyl and GSH concentrations were analyzed by spectrophotometry. Trace element concentration was quantified by atomic absorption spectrophotometry. Generalized linear modelling was used to assess the relationship between protein carbonyls concentration with oxidative stress indicators and trace elements concentration. RESULTS: Cd and Pb were detected in 21.3 and 55.6% of breast milk samples, respectively. The median concentration of Cd was 0.01 µg L-1 (0.01-3.52 µg L-1) and Pb concentration was 2.61 µg L-1 (0.08-195.20 µg L-1). According to the best-fit model, the main factors contributing to protein carbonyl concentrations were the activity of GPx, GR, and concentration of GSH, Se, Pb and Cd. CONCLUSIONS: According to the generalized linear model, the activity of GPx and GR, could help explain protein oxidation induced by Pb and Cd in breast milk.


Assuntos
Antioxidantes/análise , Metais/química , Proteínas do Leite/química , Leite Humano/química , Adulto , Feminino , Glutationa Peroxidase/química , Glutationa Redutase/química , Humanos , Metais/efeitos adversos , Metais Pesados/efeitos adversos , Metais Pesados/química , Oxirredução , Carbonilação Proteica/efeitos dos fármacos
9.
Nutr. hosp ; 34(1): 59-64, ene.-feb. 2017. tab
Artigo em Inglês | IBECS | ID: ibc-161142

RESUMO

Introduction: Breast milk contains molecules needed for the development of children; the integrity and function of these molecules is affected by the presence of pro-oxidants. Protein carbonyls are mainly produced as a result of the interaction of metals with reactive oxygen species (ROS), which may initiate a chain reaction that promotes molecular oxidation. Objective: This study aimed to determine the association between the concentration of protein carbonyls with the concentration of trace elements (lead [Pb], cadmium [Cd] and selenium [Se]), superoxide radical (O2 •-) production, and glutathione (GSH) content, as well with the activity of the main antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], glutathione reductase [GR] and glutathione S-transferase [GST]) in breast milk. Methods: In this study 108 transitional milk samples (7-10 days) were analyzed. Antioxidant enzyme activities, O2 •- production, protein carbonyl and GSH concentrations were analyzed by spectrophotometry. Trace element concentration was quantified by atomic absorption spectrophotometry. Generalized linear modelling was used to assess the relationship between protein carbonyls concentration with oxidative stress indicators and trace elements concentration. Results: Cd and Pb were detected in 21.3 and 55.6% of breast milk samples, respectively. The median concentration of Cd was 0.01 μg L-1 (0.01-3.52 μg L-1) and Pb concentration was 2.61 μg L-1 (0.08-195.20 μg L-1). According to the best-fi t model, the main factors contributing to protein carbonyl concentrations were the activity of GPx, GR, and concentration of GSH, Se, Pb and Cd. Conclusions: According to the generalized linear model, the activity of GPx and GR, could help explain protein oxidation induced by Pb and Cd in breast milk (AU)


Introducción: la leche materna contiene las moléculas necesarias para el desarrollo de los niños; la integridad y función de estas moléculas se afecta por la presencia de prooxidantes. Los carbonilos proteicos se producen principalmente como resultado de la interacción de metales con especies reactivas de oxígeno (ERO), los cuales pueden iniciar una reacción en cadena que promueve la oxidación molecular. Objetivo: este estudio tiene como objetivo determinar la asociación entre la concentración de carbonilos proteicos con la concentración de elementos traza (plomo [Pb], cadmio [Cd] y selenio [Se]), producción de radical superóxido (O2 •-), y contenido de glutatión (GSH), así como con la actividad de las principales enzimas (superóxido dismutasa [SOD], catalasa [CAT], glutatión peroxidasa [GPx], glutatión reductasa [GR] y glutatión S-transferasa [GST]) en leche materna. Métodos: en este estudio se analizaron 108 muestras de leche de transición (7-10 días). La actividad de las enzimas antioxidantes, producción de O2 •-, concentración de carbonilos proteicos y GSH se analizaron por espectrofotometría. La concentración de elementos traza se cuantificó por espectrometría de absorción atómica. Se utilizó un modelo lineal generalizado para evaluar la relación entre la concentración de carbonilos proteicos con los indicadores de estrés oxidativo y las concentraciones de elementos traza. Resultados: Cd y Pb fueron detectados en 21,3 y 55,6% de las muestras de leche materna, respectivamente. La mediana de la concentración de Cd fue 0,01 μg l-1 (0,01-3,52 μg l-1) y para la concentración de Pb fue 2,61 μg l-1 (0,08-195,20 μg l-1). De acuerdo con el modelo de mejor ajuste, los principales factores de afectan la concentración de carbonilos proteicos, son la actividad de GPx y GR, y las concentraciones de GSH, Se, Pb y Cd. Conclusiones: de acuerdo con el modelo lineal generalizado, la actividad de GPx y GR podría ayudar a explicar la oxidación proteica, inducida por Pb y Cd en leche materna (AU)


Assuntos
Humanos , Lactente , Estresse Oxidativo/fisiologia , Leite Humano/fisiologia , Proteínas do Leite/biossíntese , Marcadores Inorgânicos/análise , Antioxidantes/análise , Oligoelementos/isolamento & purificação , Superóxidos/análise , Glutationa/isolamento & purificação , Leite Humano/enzimologia
11.
Bull Environ Contam Toxicol ; 97(1): 44-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27207229

RESUMO

Areas where abandoned metal-extraction mines are located contain large quantities of mineral wastes derived from environmentally unsafe mining practices. These wastes contain many pollutants, such as heavy metals, which could be released to the environment through weathering and leaching, hence becoming an important source of environmental metal pollution. This study evaluates differences in the levels of lead, iron, nickel, manganese, copper and cadmium in rodents sharing the same type of diet under different microhabitat use in arid areas with past mining activities. Samples of soil, roots, branches and seeds of Palo Adán (Fouquieria diguetii) and specimens of two rodent species (Chaetodipus arenarius and C. spinatus) were collected in areas with impact from past metal mining activities as well as from areas with no mining impact. Both rodent species mirrored nickel and iron levels in soil and seeds, as well as lead levels in soil; however, C. arenarius accumulated higher levels of manganese, copper and cadmium.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Mineração , Oligoelementos/análise , Animais , Meio Ambiente , Poluição Ambiental/análise , Roedores , Solo/química , Poluentes do Solo/análise
12.
J Environ Sci Health B ; 51(7): 435-45, 2016 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-27050678

RESUMO

This study examines the potential public health risk due to the massive use of organochlorine pesticides (OCs) in agriculture in the Gulf of California. Specimens of the clam Chione californiensis were collected from three coastal lagoons (Yavaros, Altata and Reforma). Sites were classified as polluted/nonpolluted based on the presence/absence of OCs as an indicator of the persistence of these pollutants; in polluted sites, the time elapsed since pesticide application (past or recent) was estimated. Screening values (SV) for protecting human health as per the U.S. Environmental Protection Agency (EPA) were used for risk assessment. OCs detected were ranked according to frequency of occurrence as follows: γ-chlordane (75%) > endrin (54%) > aldrin (48%) > heptachlor, and dichlorodiphenyl-trichloroethane (DDE) (37%) > ß-heptachlor epoxide (30%) > lindane (α-BHC, δ-BHC) and endosulphan I (≤ 6%). Specifically, OCs detected at the highest concentration were heptachlor in Yavaros (0.0168 µgg(-1)) and Altata (0.0046 µgg(-1)), and aldrin in Reforma (0.0019 µgg(-1)). ß-Heptachlor epoxide in Altata and Reforma was the only OC with a concentration exceeding the EPA Screening Value. From our results and based on the monthly consumption limit set forth by EPA, the maximum safe consumption of clams to avoid a carcinogenic risk derived from ß-heptachlor epoxide in the fishing villages of Yavaros and Altata is 4 servings per month (1 serving = 0.227 kg) by a 70-kg person. These findings suggest that concentrations of OCs and their isomers in C. californiensis populations reflect environmental persistence as well as recent inputs of OCs into coastal lagoons in the Gulf of California.


Assuntos
Bivalves/química , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Frutos do Mar/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Animais , California , Monitoramento Ambiental , Humanos , Medição de Risco
13.
Nutr. hosp ; 33(2): 422-430, mar.-abr. 2016. tab, graf
Artigo em Inglês | IBECS | ID: ibc-153323

RESUMO

Introduction: Organochlorine pesticides (OCPs) can increase the production of reactive oxygen species (ROS), the effects of which can be countered by the antioxidant system, also present in breast milk. Objective: To evaluate the indicators of oxidative stress in breast milk associated to the presence of OCPs, and their relationship with seafood intake. Methods: Breast milk was collected from 108 lactating women. Indicators of oxidative stress (antioxidant enzyme activity, glutathione concentration, superoxide radical [O2 •-] production, lipid peroxidation and carbonylated protein concentration) were analyzed by spectrophotometry. OCPs concentrations were measured by gas chromatography. Results and discussion: O2 •- production had no significant relationship with OCPs concentrations. Significant correlations between OCPs concentrations and antioxidant enzyme activities (glutathione reductase [GR] activity and aldrin concentration [r = - 0.5], superoxide dismutase [SOD] activity and α-HCH concentration [r = 0.45]) were found. Oxidative damage had a low correlation with OCPs content (r < 0.30, p < 0.05). It is possible that OCP’s levels are not sufficient to increase O2 •- production, that production of ROS other than O2 •- is increased, or that the antioxidant capacity is sufficient to avoid oxidative damage in breast milk. Conclusion: Results from this study suggest that marine diet is not a determinant factor in the level of contamination by OCP’s or in the oxidative damage in breast milk (AU)


Introducción: los plaguicidas organoclorados (POC) pueden incrementar la producción de especies reactivas de oxígeno (ERO). Tales efectos pueden ser contrarrestados por el sistema antioxidante, el cual se encuentra también en la leche materna. Objetivo: evaluar los indicadores de estrés oxidativo en leche materna asociados a la presencia de POC y su relación con la ingesta de alimentos marinos. Métodos: la leche materna fue colectada de 108 mujeres lactantes. Los indicadores de estrés oxidativo (actividad enzimática antioxidante, concentración de glutatión, producción de radical superóxido [O2 •-], concentración de peroxidación de lípidos y carbonilos proteicos) se analizaron por espectrofotometría. Las concentraciones de POC se midieron por cromatografía de gases. Resultados y discusión: la producción de O2 •- no presentó relación significativa con las concentraciones de POC. Se encontraron correlaciones significativas entre las concentraciones de POC y la actividad de las enzimas antioxidantes (actividad de glutatión reductasa [GR] y concentración de aldrín [r = - 0,5], actividad de superóxido dismutasa [SOD] y concentración de α-HCH [r = 0,45]). El daño oxidativo mostró baja correlación con el contenido de POC (r < 0,30, p < 0,05). Es posible que los niveles de POC no sean suficientes para incrementar la producción de O2 •-, ya sea que el incremento en la producción de ERO se deba a especies reactivas diferentes a O2 •- o debido a que la capacidad antioxidante es suficiente para evitar el daño oxidativo en leche materna. Conclusión: los resultados de este estudio sugieren que la dieta marina no es un factor determinante en el nivel de contaminación por POC, ni en el daño oxidativo presente en leche materna (AU)


Assuntos
Humanos , Masculino , Feminino , Leite Humano/química , Antioxidantes/isolamento & purificação , Espécies Reativas de Oxigênio/isolamento & purificação , Inseticidas Organoclorados/análise , Espectrofotometria , Alimentos Marinhos/efeitos adversos , Estresse Oxidativo/fisiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-26506131

RESUMO

In mammalian tissues under hypoxic conditions, ATP degradation results in accumulation of purine metabolites. During exercise, muscle energetic demand increases and oxygen consumption can exceed its supply. During breath-hold diving, oxygen supply is reduced and, although oxygen utilization is regulated by bradycardia (low heart rate) and peripheral vasoconstriction, tissues with low blood flow (ischemia) may become hypoxic. The goal of this study was to evaluate potential differences in the circulating levels of purine metabolism components between diving and exercise in bottlenose dolphins (Tursiops truncatus). Blood samples were taken from captive dolphins following a swimming routine (n=8) and after a 2min dive (n=8). Activity of enzymes involved in purine metabolism (hypoxanthine guanine phosphoribosyl transferase (HGPRT), inosine monophosphate deshydrogenase (IMPDH), xanthine oxidase (XO), purine nucleoside phosphorylase (PNP)), and purine metabolite (hypoxanthine (HX), xanthine (X), uric acid (UA), inosine monophosphate (IMP), inosine, nicotinamide adenine dinucleotide (NAD(+)), adenosine, adenosine monophosphate (AMP), adenosine diphosphate (ADP), ATP, guanosine diphosphate (GDP), guanosine triphosphate (GTP)) concentrations were quantified in erythrocyte and plasma samples. Enzymatic activity and purine metabolite concentrations involved in purine synthesis and degradation, were not significantly different between diving and exercise. Plasma adenosine concentration was higher after diving than exercise (p=0.03); this may be related to dive-induced ischemia. In erythrocytes, HGPRT activity was higher after diving than exercise (p=0.007), suggesting an increased capacity for purine recycling and ATP synthesis from IMP in ischemic tissues of bottlenose dolphins during diving. Purine recycling and physiological adaptations may maintain the ATP concentrations in bottlenose dolphins after diving and exercise.


Assuntos
Golfinho Nariz-de-Garrafa/sangue , Mergulho , Eritrócitos/metabolismo , Hipóxia/sangue , Condicionamento Físico Animal , Purinas/metabolismo , Respiração , Animais , Eritrócitos/enzimologia , Feminino , Masculino , Metaboloma
15.
J Clin Microbiol ; 53(8): 2753-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26019205

RESUMO

We describe a fatal case of polymicrobial meningitis in a human immunodeficiency virus-infected patient from Guatemala caused by Cryptococcus liquefaciens and Mycobacterium tuberculosis complex. Central nervous system infections caused concurrently by these species are extremely rare. This is also the first report of disseminated disease caused by C. liquefaciens.


Assuntos
Coinfecção/diagnóstico , Cryptococcus/isolamento & purificação , Infecções por HIV/complicações , Meningite Criptocócica/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/diagnóstico , Adulto , Análise por Conglomerados , Coinfecção/patologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Evolução Fatal , Feminino , Guatemala , Humanos , Meningite Criptocócica/complicações , Meningite Criptocócica/patologia , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Tuberculose Meníngea/complicações , Tuberculose Meníngea/patologia
16.
Nutr Hosp ; 31(5): 2289-96, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25929406

RESUMO

Purine nucleoside phosphorylase (PNP) is an ubiquitous enzyme which plays an important role in arsenic (As) detoxification. As is a toxic metalloid present in air, soil and water; is abundant in the environment and is readily transferred along the trophic chain, being found even in human breast milk. Milk is the main nutrient source for the growth and development of neonates. Information on breast milk synthesis and its potential defense mechanism against As toxicity is scarce. In this study, PNP and antioxidant enzymes activities, as well as glutathione (GSH) and total arsenic (TAs) concentrations, were quantified in breast milk samples. PNP, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) activities and GSH concentration were determined spectrophotometrically; TAs concentration ([TAs]) was measured by atomic absorption spectrometry. Data suggest an increase in PNP activity (median = 0.034 U mg protein-1) in the presence of TAs (median = 1.16 g L(-1)). To explain the possible association of PNP activity in breast milk with the activity of the antioxidant enzymes as well as with GSH and TAs concentrations, generalized linear models were built. In the adjusted model, GPx and GR activities showed a statistically significant (p<0.01) association with PNP activity. These results may suggest that PNP activity increases in the presence of TAs as part of the detoxification mechanism in breast milk.


Assuntos
Antioxidantes/análise , Arsênico/efeitos adversos , Leite Humano/química , Purina-Núcleosídeo Fosforilase/análise , Adulto , Feminino , Humanos , Inativação Metabólica , México , Leite Humano/enzimologia
17.
Nutr. hosp ; 31(5): 2289-2296, mayo 2015. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-140403

RESUMO

Purine nucleoside phosphorylase (PNP) is an ubiquitous enzyme which plays an important role in arsenic (As) detoxification. As is a toxic metalloid present in air, soil and water; is abundant in the environment and is readily transferred along the trophic chain, being found even in human breast milk. Milk is the main nutrient source for the growth and development of neonates. Information on breast milk synthesis and its potential defense mechanism against As toxicity is scarce. In this study, PNP and antioxidant enzymes activities, as well as glutathione (GSH) and total arsenic (TAs) concentrations, were quantified in breast milk samples. PNP, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) activities and GSH concentration were determined spectrophotometrically; TAs concentration ([TAs]) was measured by atomic absorption spectrometry. Data suggest an increase in PNP activity (median = 0.034 U mg protein-1) in the presence of TAs (median = 1.16 g L-1). To explain the possible association of PNP activity in breast milk with the activity of the antioxidant enzymes as well as with GSH and TAs concentrations, generalized linear models were built. In the adjusted model, GPx and GR activities showed a statistically significant (p<0.01) association with PNP activity. These results may suggest that PNP activity increases in the presence of TAs as part of the detoxification mechanism in breast milk (AU)


Purina nucleósido fosforilasa (PNP) es una enzima ubicua que desempeña un papel importante en la desintoxicación del arsénico (As). As es un metaloide tóxico presente en el aire, el suelo y el agua; es abundante en el medio ambiente y se transfiere fácilmente a lo largo de la cadena trófica, encontrándose incluso en la leche materna humana. Información sobre la síntesis de la leche materna y su potencial mecanismo de defensa contra tóxicos es escasa. En este estudio, se cuantificó la actividad de PNP y de las enzimas antioxidantes así como la concentración de glutatión (GSH) y de arsénico total ([TAs]) en muestras de leche materna. La actividad de PNP, superóxido dismutasa (SOD), catalasa (CAT), glutatión S-transferasa (GST), glutatión peroxidasa (GPx), glutatión reductasa (GR) y la concentración de GSH se determinaron por espectrofotometría; la [TAs] se midió por espectrometría de absorción atómica. Los datos sugieren un incremento en la actividad de PNP (mediana= 0.034 U mg proteína-1) con la presencia de TAs (mediana= 1.16 g L-1). Para explicar la posible asociación de la actividad de las enzimas antioxidantes y la concentración de GSH, así como [TAs], con la actividad de PNP en la leche materna, se construyeron modelos lineales generalizados. En el modelo ajustado, la actividad de GPx y GR presentó una asociación estadística (p<0.01) con la actividad de PNP. Los resultados pueden sugerir que la actividad de PNP aumenta con la presencia de TAs como parte del mecanismo de desintoxicación en la leche materna (AU)


Assuntos
Feminino , Humanos , Intoxicação por Arsênico/epidemiologia , Arsênico/isolamento & purificação , Exposição Ambiental/estatística & dados numéricos , Leite Humano/química , Inativação Metabólica/fisiologia , Fosforilases/análise , Nucleotídeos de Purina/análise , Antioxidantes/farmacocinética , Estresse Oxidativo
18.
Nutr Hosp ; 30(2): 436-46, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25208800

RESUMO

Breast milk is regarded as an ideal source of nutrients for the growth and development of neonates, but it can also be a potential source of pollutants. Mothers can be exposed to different contaminants as a result of their lifestyle and environmental pollution. Mercury (Hg) and arsenic (As) could adversely affect the development of fetal and neonatal nervous system. Some fish and shellfish are rich in selenium (Se), an essential trace element that forms part of several enzymes related to the detoxification process, including glutathione S-transferase (GST). The goal of this study was to determine the interaction between Hg, As and Se and analyze its effect on the activity of GST in breast milk. Milk samples were collected from women between day 7 and 10 postpartum. The GST activity was determined spectrophotometrically; total Hg, As and Se concentrations were measured by atomic absorption spectrometry. To explain the possible association of Hg, As and Se concentrations with GST activity in breast milk, generalized linear models were constructed. The model explained 44% of the GST activity measured in breast milk. The GLM suggests that GST activity was positively correlated with Hg, As and Se concentrations. The activity of the enzyme was also explained by the frequency of consumption of marine fish and shellfish in the diet of the breastfeeding women.


Assuntos
Arsênico/farmacologia , Peixes , Contaminação de Alimentos , Alimentos , Glutationa Transferase/efeitos dos fármacos , Mercúrio/farmacologia , Leite Humano/efeitos dos fármacos , Leite Humano/enzimologia , Selênio/farmacologia , Frutos do Mar , Animais , Arsênico/análise , Interações Medicamentosas , Ingestão de Alimentos , Feminino , Contaminação de Alimentos/análise , Humanos , Mercúrio/análise , Leite Humano/química , Selênio/análise
19.
Nutr Hosp ; 30(3): 540-7, 2014 Sep 01.
Artigo em Espanhol | MEDLINE | ID: mdl-25238829

RESUMO

INTRODUCTION: Breast milk is a specific combination of nutrients and immunologic factors; however, milk components may be exposed to oxidation processes, which can in turn be counteracted by antioxidant molecules such as vitamins and antioxidant enzymes, amongst others. Both antioxidant defences and oxidative damage can be affected by age, number of pregnancies and other factors. OBJECTIVE: To compare antioxidant defences and oxidative damage indicators in breast milk, according to age of women and number of pregnancies. METHOD: Activity of the main antioxidant enzymes, glutathione concentration, oxidative damage to lipids (thiobarbituric acid reactive substances, TBARS) and oxidative damage to proteins (protein carbonyls) was measured in breast milk using spectrophotometric techniques. Data were grouped according to number of pregnancies (1, 2 and 3 or more) and were related to the age of mothers. RESULTS: Significant differences among groups according to number of pregnancies were found in TBARS levels (p = 0.04) and GST activity (p < 0.01). Also linear correlations between age, lipid peroxidation and GST activity were found. CONCLUSION: The age and number of pregnancies apparently increase lipid oxidation in milk due to increased metabolism and production of reactive oxygen species. However, TBARS levels remain relatively low probably because of the mother's antioxidant defenses, particularly GST.


Assuntos
Antioxidantes/análise , Lactação/metabolismo , Leite Humano/química , Paridade , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Estresse Oxidativo , Adulto Jovem
20.
Nutr. hosp ; 30(3): 540-547, sept. 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-143775

RESUMO

Introducción: La leche materna es una combinación específica de nutrientes y factores inmunológicos; sin embargo, sus componentes pueden estar expuestos a procesos de oxidación, mismos que pueden ser contrarrestados por moléculas antioxidantes como vitaminas y enzimas, entre otros. Tanto las defensas antioxidantes como el daño oxidativo pueden ser afectados por la edad, número de gestas y otros factores. Objetivo: Comparar el contenido de antioxidantes e indicadores de daño oxidativo en leche materna de acuerdo a la edad de las mujeres y el número de gestas. Metodología: Se midió la actividad de las principales enzimas antioxidantes, la concentración de glutatión, el daño oxidativo a lípidos (sustancias reactivas al ácido tiobarbitúrico, TBARS) y daño a proteínas (carbonilos proteicos) en leche materna utilizando técnicas espectrofotométricas. Se agruparon los datos de acuerdo al número de gestas (1, 2 y 3 o más) y se correlacionó con la edad de las madres. Resultados: Se encontraron diferencias significativas en los niveles de TBARS (p = 0.04) y la actividad de glutatión S-transferasa (GST, p < 0.01) entre los grupos de acuerdo al número de gestas. Así mismo, se encontraron correlaciones lineales entre la edad, el daño oxidativo a lípidos y la actividad de GST. Conclusión: La edad y el número de gestas al parecer incrementan la oxidación de los lípidos presentes en leche materna debido al aumento en el metabolismo y la producción de especies reactivas de oxígeno. Sin embargo, los niveles de TBARS se mantienen relativamente bajos posiblemente debido a las defensas antioxidantes, particularmente GST, de la madre (AU)


Introduction: Breast milk is a specific combination of nutrients and immunologic factors; however, milk components may be exposed to oxidation processes, which can in turn be counteracted by antioxidant molecules such as vitamins and antioxidant enzymes, amongst others. Both antioxidant defences and oxidative damage can be affected by age, number of pregnancies and other factors. Objective: To compare antioxidant defences and oxidative damage indicators in breast milk, according to age of women and number of pregnancies. Method: Activity of the main antioxidant enzymes, glutathione concentration, oxidative damage to lipids (thiobarbituric acid reactive substances, TBARS) and oxidative damage to proteins (protein carbonyls) was measured in breast milk using spectrophotometric techniques. Data were grouped according to number of pregnancies (1, 2 and 3 or more) and were related to the age of mothers. Results: Significant differences among groups according to number of pregnancies were found in TBARS levels (p = 0.04) and GST activity (p < 0.01). Also linear correlations between age, lipid peroxidation and GST activity were found. Conclusion: The age and number of pregnancies apparently increase lipid oxidation in milk due to increased metabolism and production of reactive oxygen species. However, TBARS levels remain relatively low probably because of the mother’s antioxidant defenses, particularly GST (AU)


Assuntos
Humanos , Antioxidantes/isolamento & purificação , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Leite Humano/enzimologia , Idade Materna , Número de Gestações , Estresse Oxidativo , Enzimas/análise , Glutationa/análise
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