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1.
Food Chem ; 167: 418-24, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25149006

RESUMEN

The incidence of chronic diseases increases with advancing age of the population. A commonly discussed cause of chronic diseases is oxidative stress, which occurs in the body when there is an imbalance between the formation and inactivation of so-called reactive oxygen species (ROS). Epidemiological data suggest that a 'healthy diet', with a high content of flavonoids indicates preventive properties and correlates with an inverse effect with respect to the risk of chronic diseases. Berries (especially bilberries, Vaccinium myrtillus L.) are an important source of these flavonoids. In this study, we investigated, in vitro, the antioxidative properties of fractions obtained from a commercially available anthocyanin-rich bilberry extract (BE). As markers for antioxidative activity, the intracellularly generated ROS levels, oxidative DNA damage, and total glutathione (tGSH) levels were determined in the human colon cell lines Caco-2 and HT-29. In Caco-2 cells, the ROS levels and, in both cell lines, the oxidative DNA damage, were significantly reduced in the presence of the original BE and phenolcarbonic acid-rich fraction. Total GSH levels were slightly increased after pretreatment with BE, phenolcarbonic acid and the polymeric fractions, but not with the anthocyanin fraction. In summary, the BE and the therefrom-isolated phenolcarbonic acid-rich fraction, showed the most potent antioxidative activity whereas the polymeric and anthocyanin-rich fraction, in total, were less active.


Asunto(s)
Antocianinas/química , Fraccionamiento Químico/métodos , Extractos Vegetales/química , Vaccinium myrtillus/química , Antioxidantes , Daño del ADN , Flavonoides , Frutas/metabolismo , Humanos , Estrés Oxidativo , Especies Reactivas de Oxígeno
2.
HIV Med ; 12(2): 78-86, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20500231

RESUMEN

BACKGROUND: The pathogenesis of HIV/hepatitis C virus (HCV) coinfection is poorly understood. We examined markers of oxidative stress, plasma antioxidants and liver disease in HIV/HCV-coinfected and HIV-monoinfected adults. METHODS: Demographics, medical history, and proof of infection with HIV, hepatitis A virus (HAV), hepatitis B virus (HBV) and HCV were obtained. HIV viral load, CD4 cell count, complete blood count (CBC), complete metabolic panel, lipid profile, and plasma concentrations of zinc, selenium, and vitamins A and E were determined. Malondialdehyde (MDA) and glutathione peroxidase concentrations were obtained as measures of oxidative stress. Aminotransferase to platelet ratio index (APRI) and fibrosis index (FIB-4) markers were calculated. RESULTS: Significant differences were found between HIV/HCV-coinfected and HIV-monoinfected participants in levels of alanine aminotransferase (ALT) (mean±standard deviation: 51.4±50.6 vs. 31.9±43.1 U/L, respectively; P=0.014), aspartate aminotransferase (AST) (56.2±40.9 vs. 34.4±30.2 U/L; P<0.001), APRI (0.52±0.37 vs. 0.255±0.145; P=0.0001), FIB-4 (1.64±.0.91 vs. 1.03±0.11; P=0.0015) and plasma albumin (3.74±0.65 vs. 3.94±0.52 g/dL; P=0.038). There were no significant differences in CD4 cell count, HIV viral load or antiretroviral therapy (ART) between groups. Mean MDA was significantly higher (1.897±0.835 vs. 1.344± 0.223 nmol/mL, respectively; P=0.006) and plasma antioxidant concentrations were significantly lower [vitamin A, 39.5 ± 14.1 vs. 52.4±16.2 µg/dL, respectively (P=0.0004); vitamin E, 8.29±2.1 vs. 9.89±4.5 µg/mL (P=0.043); zinc, 0.61±0.14 vs. 0.67±0.15 mg/L (P=0.016)] in the HIV/HCV-coinfected participants than in the HIV-monoinfected participants, and these differences remained significant after adjusting for age, gender, CD4 cell count, HIV viral load, injecting drug use and race. There were no significant differences in glutathione peroxidase concentration, selenium concentration, body mass index (BMI), alcohol use or tobacco use between groups. Glutathione peroxidase concentration significantly increased as liver disease advanced, as measured by APRI (ß=0.00118; P=0.0082) and FIB-4 (ß=0.0029; P=0.0177). Vitamin A concentration significantly decreased (ß=-0.00581; P=0.0417) as APRI increased. CONCLUSION: HIV/HCV coinfection is associated with increased oxidative stress and decreased plasma antioxidant concentrations compared with HIV monoinfection. Research is needed to determine whether antioxidant supplementation delays liver disease in HIV/HCV coinfection.


Asunto(s)
Hepatitis C/sangre , Hepatitis C/complicaciones , Estrés Oxidativo/fisiología , Abuso de Sustancias por Vía Intravenosa/sangre , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Antioxidantes/metabolismo , Recuento de Linfocito CD4 , Femenino , Florida , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Humanos , Masculino
3.
Neurosci Lett ; 345(1): 13-6, 2003 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-12809977

RESUMEN

When exposed to female odors, testosterone-primed male mice show a robust expression of immediate early genes in the vomeronasal organ (VNO) and associated accessory olfactory structures. We asked whether the superior cervical ganglia (SCG), which provide autonomic inputs to the VNO, are required for odor induction of Fos. Gonadally intact male mice received sham, unilateral, or bilateral SCG lesions and were exposed to odors from estrous females. In comparison to clean bedding, female odors significantly increased neuronal Fos immunoreactivity in sites throughout the VNO projection pathway, but these responses were not reliably modified by SCG removal. Thus, noradrenergic inputs to the VNO, which regulate a pumping mechanism thought to facilitate entrance of chemosignals into the VNO lumen, are not required for odors to induce Fos in the mouse accessory olfactory system.


Asunto(s)
Bulbo Olfatorio/metabolismo , Feromonas , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Ganglio Cervical Superior/fisiología , Órgano Vomeronasal/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Femenino , Hipotálamo/metabolismo , Masculino , Ratones , Núcleos Septales/metabolismo
4.
Proc Natl Acad Sci U S A ; 99(14): 9231-6, 2002 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-12093923

RESUMEN

To determine whether calcium polyvalent cation-sensing receptors (CaRs) are salinity sensors in fish, we used a homology-based cloning strategy to isolate a 4.1-kb cDNA encoding a 1,027-aa dogfish shark (Squalus acanthias) kidney CaR. Expression studies in human embryonic kidney cells reveal that shark kidney senses combinations of Ca(2+), Mg(2+), and Na(+) ions at concentrations present in seawater and kidney tubules. Shark kidney is expressed in multiple shark osmoregulatory organs, including specific tubules of the kidney, rectal gland, stomach, intestine, olfactory lamellae, gill, and brain. Reverse transcriptase-PCR amplification using specific primers in two teleost fish, winter flounder (Pleuronectes americanus) and Atlantic salmon (Salmo salar), reveals a similar pattern of CaR tissue expression. Exposure of the lumen of winter flounder urinary bladder to the CaR agonists, Gd(3+) and neomycin, reversibly inhibit volume transport, which is important for euryhaline teleost survival in seawater. Within 24-72 hr after transfer of freshwater-adapted Atlantic salmon to seawater, there are increases in their plasma Ca(2+), Mg(2+), and Na(+) that likely serve as a signal for internal CaRs, i.e., brain, to sense alterations in salinity in the surrounding water. We conclude that CaRs act as salinity sensors in both teleost and elasmobranch fish. Their tissue expression patterns in fish provide insights into CaR functions in terrestrial animals including humans.


Asunto(s)
Calcio/metabolismo , Peces/metabolismo , Secuencia de Aminoácidos , Animales , Células Cultivadas , ADN Complementario/genética , Cazón/genética , Cazón/metabolismo , Peces/genética , Lenguado/genética , Lenguado/metabolismo , Humanos , Riñón/metabolismo , Magnesio/metabolismo , Datos de Secuencia Molecular , Estructura Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Sensibles al Calcio , Receptores de Superficie Celular/química , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Salmo salar/genética , Salmo salar/metabolismo , Agua de Mar , Homología de Secuencia de Aminoácido , Sodio/metabolismo , Cloruro de Sodio , Distribución Tisular , Transfección , Vejiga Urinaria/metabolismo
5.
Mol Genet Genomics ; 265(6): 1097-103, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11523782

RESUMEN

Microsatellites, very short tandemly repeated DNA sequences, are being extensively used in evolutionary genetics and molecular breeding of crop plants, because of their high degree of allelic variability, which is presumably caused by a high rate of mutation that changes microsatellite array length. In humans and various animals, mutation rates vary greatly and fall within the range of 10(-3) to 10(-6). In plants, the mutation rate at microsatellite loci seems to be higher than in animals, but no experimental estimates are available yet. Here, we report high spontaneous mutation rates (micro) and mutational bias at fifteen perfect (TAA)n microsatellite loci in inbred populations of chickpea. We show a significantly higher mutation rate, averaged across all loci, in the long-lived variety Ghab 2 (mu = 1.0 x 10(-2); detected in 16,050 allele-generations) compared to the variety Syrian Local (mu = 3.9 x 10(-3); detected in 15,600 allele-generations), which has a short life-span, with the majority of mutants (96.9%) in both varieties differing by < or = 1 repeat unit. Compared to animals, higher mutation rates in chickpea are likely to be due to the presence of long (TAA)n microsatellite repeat arrays and the larger number of DNA replications that meristematic initials of the plants undergo before reaching the reproductive phase. Thus, the long-lived variety undergoes more DNA replications, resulting in an accumulation of more mutations than in the variety with the shorter life-span.


Asunto(s)
ADN de Plantas/genética , Fabaceae/genética , Repeticiones de Microsatélite/genética , Mutación , Plantas Medicinales , Expansión de Repetición de Trinucleótido/genética , Secuencia de Bases , ADN de Plantas/química , Secuencias Repetitivas de Ácidos Nucleicos
6.
J Neuroendocrinol ; 13(6): 551-60, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11412342

RESUMEN

Previous research demonstrated that exposing gonadectomized adult ferrets to odours in oestrous female bedding induced nuclear Fos-immunoreactivity (Fos-IR; a marker of neuronal activity) in the main as opposed to the accessory olfactory system in a sexually dimorphic fashion, which was further augmented in both sexes by treatment with testosterone propionate. Ferrets are born in an altricial state and presumably use maternal odour cues to locate the nipples until the eyes open after postnatal (P) day 23. We investigated whether maternal odours augment neuronal Fos preferentially in the main versus accessory olfactory system of neonatal male and female ferret kits. Circulating testosterone levels peak in male ferrets on postnatal day P15, and mothers provide maximal anogenital stimulation (AGS) to males at this same age. Therefore, we assessed the ability of maternal odours to augment Fos-IR in the accessory olfactory bulb (AOB), the main olfactory bulb (MOB) and other forebrain regions of male and female ferret kits on P15 and investigated whether artificial AGS (provided with a paintbrush) would further enhance any effects of maternal odours. After separation from their mothers for 4 h, groups of male and female kits that were placed for 1.5 h with their anaesthetized mother had significantly more Fos-IR cells in the MOB granule cell layer and in the anterior-cortical amygdala, but not in the AOB cell layer, compared to control kits that were left on the heating pad. Artificial AGS failed to amplify these effects of maternal odours. Maternal odours (with or without concurrent AGS) failed to augment neuronal Fos-IR in medial amygdaloid and hypothalamic regions that are activated in adult ferrets by social odours. In neonatal ferrets of both sexes, as in adults, socially relevant odours are detected by the main olfactory epithelium and initially processed by the MOB and the anterior-cortical amygdala. In neonates, unlike adults, medial amygdaloid and hypothalamic neurones either do not respond to these inputs or respond in a manner that fails to induce Fos expression.


Asunto(s)
Hurones/fisiología , Odorantes , Bulbo Olfatorio/metabolismo , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Envejecimiento , Animales , Femenino , Hipotálamo/metabolismo , Masculino , Madres , Neuronas/metabolismo , Área Preóptica/metabolismo , Proteínas Proto-Oncogénicas c-fos/análisis , Testosterona/sangre
7.
Cancer Res ; 61(4): 1457-63, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11245451

RESUMEN

Beta-carotene has established efficacy in animal models of oral carcinogenesis and has been shown to regress oral precancerous lesions in humans. The purpose of this study was to see whether these effects extended to the prevention of oral/pharyngeal/laryngeal (head and neck) cancer in humans. The subject population for this randomized, placebo-controlled, double-blinded clinical trial included 264 patients who had been curatively treated for a recent early-stage squamous cell carcinoma of the oral cavity, pharynx, or larynx. Patients were assigned randomly to receive 50 mg of beta-carotene per day or placebo and were followed for up to 90 months for the development of second primary tumors and local recurrences. After a median follow-up of 51 months, there was no difference between the two groups in the time to failure [second primary tumors plus local recurrences: relative risk (RR), 0.90; 95% confidence interval (CI), 0.56-1.45]. In site-specific analyses, supplemental beta-carotene had no significant effect on second head and neck cancer (RR, 0.69; 95% CI, 0.39-1.25) or lung cancer (RR, 1.44; 95% CI, 0.62-3.39). Total mortality was not significantly affected by this intervention (RR, 0.86; 95% CI, 0.52-1.42). Whereas none of the effects were statistically significant, the point estimates suggested a possible decrease in second head and neck cancer risk but a possible increase in lung cancer risk. These effects are consistent with the effects observed in trials using intermediate end point biological markers in humans, in which beta-carotene has established efficacy in oral precancerous lesions but has no effect or slightly worsens sputum cytology, and in animal carcinogenicity studies, in which beta-carotene has established efficacy in buccal pouch carcinogenesis in hamsters but not in animal models of respiratory tract/lung carcinogenesis, with some suggestions of tumor-promoting effects in respiratory tract/lung. If our results are replicated by other ongoing/completed trials, this suggests a critical need for mechanistic studies addressing differential responses in one epithelial site (head and neck) versus another (lung).


Asunto(s)
Anticarcinógenos/uso terapéutico , Antioxidantes/uso terapéutico , Carcinoma de Células Escamosas/prevención & control , Neoplasias de Cabeza y Cuello/prevención & control , Neoplasias Primarias Secundarias/prevención & control , beta Caroteno/uso terapéutico , Adulto , Anciano , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/mortalidad , Suplementos Dietéticos , Método Doble Ciego , Femenino , Neoplasias de Cabeza y Cuello/sangre , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Secundarias/sangre , Neoplasias Primarias Secundarias/mortalidad , Placebos , beta Caroteno/sangre
8.
Platelets ; 12(8): 456-61, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11798394

RESUMEN

The present case-control study compared 26 HIV+ drug users having persistent thrombocytopenia (TCP<150 000/mm(3)) with 54 available age, gender and HIV CDC classification matched controls with normal platelet counts. Participants were followed longitudinally over a 2-year period (1998-2000), and hematological alterations evaluated in relationship to antiretroviral treatment, drug use and nutritional (selenium) status. Demographic information and medical history, including antiretroviral treatment were obtained. Blood was drawn for complete cell blood count, T lymphocytes and viral load. Sixty-nine percent of the individuals with persistent TCP and 49% of the controls were receiving antiretrovirals. At baseline, no significant differences in CD4 existed between the two groups. Over time, CD4 cell count declined in the cases (P = 0.05) and a significantly higher proportion of the cases (38%) developed AIDS (CD4<200 cell/mm(3)), as compared to the controls (18%, P = 0.004). A high risk for development of thrombocytopenia was observed with specific drug use (heroin 2.96 times, P = 0.0007), selenium levels below 145 microg/l (6 times, P = 0.008), and abnormal liver enzyme (SGOT) levels (2 times, P = 0.002). Together, these results indicate a number of factors that may be sensitive predictors of thrombocytopenia, which, despite antiretroviral treatment, appears to be related to more rapid disease progression in drug users.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Abuso de Sustancias por Vía Intravenosa/complicaciones , Trombocitopenia/complicaciones , Adulto , Terapia Antirretroviral Altamente Activa , Aspartato Aminotransferasas/efectos adversos , Aspartato Aminotransferasas/análisis , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estado Nutricional , Recuento de Plaquetas , Selenio/análisis , Carga Viral
9.
J Acquir Immune Defic Syndr ; 25 Suppl 1: S49-52, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11126427

RESUMEN

Nutritional deficiencies are widespread among HIV-1-seropositive male and female drug abusers (injecting drug users, or IDUs), among men who have sex with men (MSM), and among children, although the prevalence of nutritional alterations varies among the groups. Low levels of vitamin A, vitamin B12, zinc, and selenium are common and have been demonstrated to be associated with disease progression and HIV-1 related mortality, independent of CD4 count <200 cells/mm3 at baseline and CD4 count over time. When all nutrient factors that are associated with survival are considered together, only selenium deficiency is a significant predictor of mortality. The profound effect of selenium on disease progression may reflect selenium's action in antioxidant defense systems, as well as gene regulation.


Asunto(s)
Infecciones por VIH/complicaciones , VIH-1 , Micronutrientes/fisiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Infecciones por VIH/mortalidad , Infecciones por VIH/fisiopatología , Humanos , Lactante , Masculino , Micronutrientes/deficiencia , Selenio/deficiencia , Selenio/fisiología
10.
J Infect Dis ; 182 Suppl 1: S69-73, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10944486

RESUMEN

An important role for selenium in human immunodeficiency virus (HIV) disease has been proposed. Decreased selenium levels, as found in persons with HIV infection or AIDS, are sensitive markers of disease progression. Selenium deficiency, an independent predictor of mortality in both HIV-1-infected adults and children, is an essential micronutrient that is associated with an improvement of T cell function and reduced apoptosis in animal models. In addition, adequate selenium may enhance resistance to infections through modulation of interleukin (IL) production and subsequently the Th1/Th2 response. Selenium supplementation up-regulates IL-2 and increases activation, proliferation, differentiation, and programmed cell death of T helper cells. Moreover, selenium supplementation may down-regulate the abnormally high levels of IL-8 and tumor necrosis factor-alpha observed in HIV disease, which has been associated with neurologic damage, Kaposi's sarcoma, wasting syndrome, and increased viral replication. Together, these findings suggest a new mechanism through which selenium may affect HIV-1 disease progression.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/sangre , Infecciones por VIH/sangre , VIH-1 , Interleucinas/sangre , Selenio/sangre , Linfocitos T/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Adulto , Niño , Infecciones por VIH/inmunología , VIH-1/efectos de los fármacos , VIH-1/fisiología , Humanos , Selenio/farmacología , Células TH1/inmunología , Células Th2/inmunología , Replicación Viral/efectos de los fármacos
12.
Behav Neurosci ; 113(2): 391-400, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10357463

RESUMEN

Gonadectomized, estradiol-treated male and female ferrets (Mustela furo) received intracerebroventricular (i.c.v.) infusions of 4 doses of the galanin receptor antagonist M40 or galanin and were allowed to approach breeding male or female ferrets that were placed behind wire mesh barriers in the goal boxes of a T maze. After i.c.v. infusion of saline, subjects strongly preferred to approach stimulus ferrets of the opposite sex. Male and female subjects approached these preferred stimulus animals on significantly fewer trials after i.c.v. infusion of the 2 highest doses of M40, whereas this drug failed to affect males' coital behavior in separate tests with an estrous female. Endogenous galanin may facilitate neural reward mechanisms that control heterosexual partner preference in both sexes.


Asunto(s)
Galanina/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , Conducta Sexual Animal/efectos de los fármacos , Conducta Sexual Animal/fisiología , Análisis de Varianza , Angiotensina II/farmacología , Animales , Femenino , Hurones , Heterosexualidad , Hipotálamo/citología , Inyecciones Intraventriculares , Masculino , Aprendizaje por Laberinto , Área Preóptica/citología , Caracteres Sexuales , Cloruro de Sodio/administración & dosificación
13.
J Acquir Immune Defic Syndr Hum Retrovirol ; 20(5): 508-13, 1999 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10225235

RESUMEN

OBJECTIVE: To determine the independent contribution of specific nutritional factors on disease progression and survival in HIV-1-infected children. POPULATION: HIV-infected children (N = 24), who were perinatally exposed to the virus and symptomatic, were recruited between October and December of 1990 from the Jackson Memorial Pediatric Immunology Clinic, Miami, Florida, and observed for 5 years. METHODS: Immune status was measured by CD4 cell count; nutritional status was determined using serum albumin and plasma trace elements including iron, zinc, and selenium. Cox proportional hazards regression models were used to evaluate the relationship of these parameters to survival. Use of antiretroviral treatment was considered in the statistical model, and age at death was considered a parameter of disease progression. RESULTS: Over the course of the study, 12 children died of HIV-related causes. The final Cox multivariate analysis indicated that, of the variables evaluated, only CD4 cell count below 200 (risk ratio [RR] = 7.05; 95% confidence interval [CI], 1.87-26.5); p = .004], and low levels of plasma selenium (RR = 5.96; 95% CI, 1.32-26.81; p = .02) were significantly and independently related to mortality. Among the children who died, those with low selenium levels (< or =85 microg/L), died at a younger age, suggesting more rapid disease progression. CONCLUSIONS: In pediatric HIV-infection, low plasma level of selenium is an independent predictor of mortality, and appears to be associated with faster disease progression.


Asunto(s)
Seropositividad para VIH/mortalidad , Selenio/deficiencia , Niño , Preescolar , Femenino , Seropositividad para VIH/fisiopatología , Humanos , Lactante , Masculino , Estado Nutricional , Factores de Riesgo
14.
Mol Gen Genet ; 261(2): 354-63, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10102371

RESUMEN

A set of 12 randomly selected (TAA)n microsatellite loci of the cultivated chickpea (Cicer arietinum L.) were screened in a worldwide sample comprising 72 landraces, four improved cultivars and two wild species of the primary gene pool (C. reticulatum and C. echinosperum) to determine the level and pattern of polymorphism in these populations. A single fragment was amplified from all the accessions with each of 12 sequence-tagged microsatellite site markers, except for one locus where no fragment was obtained from either of the two wild species. There was a high degree of intraspecific polymorphism at these microsatellite loci, although isozymes, conventional RFLPs and RAPDs show very little or no polymorphism. Overall, the repeat number at a locus (excluding null alleles) ranged from 7 to 42. The average number of alleles per locus was 14.1 and the average genetic diversity was 0.86. Based on the estimates obtained, 11 out of the 12 frequency distributions of alleles at the loci tested can be considered to be non-normal. A significant positive correlation between the average number of repeats (size of the locus) and the amount of variation was observed, indicating that replication slippage may be the molecular mechanism involved in generation of variability at the loci. A comparison between the infinite allele and stepwise mutation models revealed that for 11 out of the 12 loci the number of alleles observed fell in between the values predicted by the two models. Phylogenetic analysis of microsatellite polymorphism in C. arietinum showed no relationship between accession and geographic origin, which is compatible with the recent expansion of this crop throughout the world.


Asunto(s)
Alelos , Fabaceae/genética , Genes de Plantas , Variación Genética , Plantas Medicinales , Repeticiones de Trinucleótidos , Fabaceae/clasificación , Filogenia
15.
Biol Reprod ; 59(6): 1454-63, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9828192

RESUMEN

A carnivore, the ferret possesses a vomeronasal organ--accessory olfactory bulb (VNO-AOB) projection to the hypothalamus; however, little is known about its function. Pheromones in soiled bedding from estrous female ferrets or an artificial peppermint odor significantly augmented nuclear Fos protein immunoreactivity (Fos-IR), a marker of neural activation, in several main olfactory bulb (MOB) sites but not in the AOB of gonadectomized male and females. Testosterone propionate (TP) significantly augmented the MOB's neuronal Fos responses to estrous females' pheromones, but not to peppermint. Estrous odors, but not peppermint, also augmented neuronal Fos-IR in the medial preoptic area (mPOA) of female, but not male, subjects. Pheromones in soiled bedding from breeding male ferrets significantly augmented neuronal Fos-IR in the MOB and in the medial amygdala of gonadectomized, TP-treated male and female subjects. Again, male pheromones failed to influence neuronal Fos-IR in the AOB of either sex, and only females showed significant increases in neuronal Fos-IR in the lateral aspect of the ventromedial nucleus and mPOA. These results point to an essential role among higher mammals of the main olfactory epithelium-MOB projection to the hypothalamus in detecting and processing pheromones. Gonadectomized ferrets showed significant increases in sniffing behavior when placed on either female or male bedding. This occurred regardless of whether they had received TP or oil vehicle, suggesting that testosterone's facilitation of neuronal Fos responses to estrous females' odors in the MOB of both sexes cannot be attributed to increased scent gathering. Androgen receptor-IR was present in the MOB granule cell layer of male and female ferrets, raising the possibility that testosterone acts directly on these cells to augment their responsiveness to pheromones.


Asunto(s)
Hurones/metabolismo , Hipotálamo/metabolismo , Bulbo Olfatorio/metabolismo , Feromonas/farmacología , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Testosterona/farmacología , Animales , Conducta Animal/fisiología , Estro/fisiología , Femenino , Masculino , Mentha piperita , Neuronas/metabolismo , Odorantes , Extractos Vegetales , Proteínas Proto-Oncogénicas c-fos/análisis , Caracteres Sexuales
16.
Am J Clin Nutr ; 68(3): 642-7, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9734742

RESUMEN

High doses of beta-carotene, a lipid-soluble nutrient, may affect the plasma concentrations of other lipid-soluble nutrients. The purpose of this study was to assess the effects of long-term daily supplementation with beta-carotene (50 mg/d) on circulating concentrations of other carotenoids, retinol, and alpha-tocopherol over time. Data were available from 259 men and women participating in the Carotene Prevention Trial, a 2-center chemoprevention trial designed to determine whether supplemental beta-carotene can prevent second malignant tumors in patients cured of an early stage cancer of the oral cavity, pharynx, or larynx. Up to 2 blood samples were obtained before the intervention (before and after a 1-mo placebo run-in), with postrandomization samples obtained at 3, 12, 24, 36, 48, and 60 mo. Supplementation with beta-carotene produced a persistent 9- to 10-fold increase in median plasma beta-carotene concentrations (225 nmol/L at baseline to 2255 nmol/L at 3 mo) and a persistent 2-fold increase in median plasma alpha-carotene concentrations (45 nmol/L at baseline to 95 nmol/L at 3 mo). Concentrations of retinol, alpha-tocopherol, lycopene, and lutein/zeaxanthin were not affected by supplemental beta-carotene. Up to 5 y of daily supplementation with beta-carotene increased circulating concentrations of alpha- and beta-carotene, but did not alter concentrations of lycopene, lutein/zeaxanthin, retinol, or alpha-tocopherol.


Asunto(s)
Carotenoides/sangre , Suplementos Dietéticos , Vitamina A/sangre , Vitamina E/sangre , beta Caroteno/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , beta Caroteno/uso terapéutico
17.
Nutr Rev ; 56(1 Pt 2): S135-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9481135

RESUMEN

Selenium deficiency has been demonstrated to be a significant predictor of HIV-related mortality, independent of CD4 over time, CD4 < 200 at baseline, and antiretroviral treatment. Although selenium deficiency in healthy humans is relatively rare (Cohen et al. 1989, Lockitch, 1989), a number of studies have documented a decline in plasma selenium levels and decreased glutathione peroxidase activity in individuals with HIV/AIDS (Dworkin et al. 1988, Cirelli et al. 1991, Mantero-Atienza et al. 1991, Staal et al. 1992, Allavena et al. 1995). These findings are of particular concern in light of selenium's influence on immune function, viral replication, and survival. As recent investigations (Delmas-Beauvieux et al. 1996) indicate that supplementation with selenium may help to increase the enzymatic defense systems in HIV-infected patients, further studies to determine possible mechanisms and clinical trials to evaluate the effect of selenium supplementation on HIV disease progression are essential.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/mortalidad , Micronutrientes , Estado Nutricional , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Femenino , Humanos , Masculino , Trastornos Nutricionales/complicaciones
18.
Artículo en Inglés | MEDLINE | ID: mdl-9342257

RESUMEN

To determine the independent contribution of specific immunologic and nutritional factors on survival in HIV-1 disease, CD4 cell count, antiretroviral treatment, plasma levels of vitamins A, E, B6, and B12 and minerals selenium and zinc were considered in relation to relative risk for HIV-related mortality. Immune parameters and nutrients known to affect immune function were evaluated at 6-month intervals in 125 HIV-1-seropositive drug-using men and women in Miami, FL, over 3.5 years. A total of 21 of the HIV-1-infected participants died of HIV-related causes during the 3.5-year longitudinal study. Subclinical malnutrition (i.e., overly low levels of prealbumin, relative risk [RR] = 4.01, p < 0.007), deficiency of vitamin A (RR = 3.23, p < 0.03), vitamin B12 deficiency (RR = 8.33, p < 0.009), zinc deficiency (RR = 2.29.1, p < 0.04), and selenium deficiency (RR = 19.9, p < 0.0001) over time, but not zidovudine treatment, were shown to each be associated with HIV-1-related mortality independent of CD4 cell counts <200/mm3 at baseline, and CD4 counts over time. When all factors that could affect survival, including CD4 counts <200/mm3 at baseline, CD4 levels over time, and nutrient deficiencies were considered jointly, only CD4 counts over time (RR = 0.69, p < 0.04) and selenium deficiency (RR = 10.8, p < 0.002) were significantly associated with mortality. These results indicate that selenium deficiency is an independent predictor of survival for those with HIV-1 infection.


Asunto(s)
Infecciones por VIH/mortalidad , VIH-1 , Selenio/deficiencia , Adulto , Avitaminosis/complicaciones , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , VIH-1/inmunología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Trastornos Nutricionales/complicaciones , Estado Nutricional , Prealbúmina/análisis , Modelos de Riesgos Proporcionales , Factores de Riesgo , Trastornos Relacionados con Sustancias/complicaciones , Zinc/deficiencia
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