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1.
Clin Rheumatol ; 35(2): 513-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26024586

RESUMEN

Alkaptonuria (AKU) is a rare genetic disease resulting in severe, rapidly progressing, early onset multi-joint osteoarthropathy. A potential therapy, nitisinone, is being trialled that reduces the causative agent; homogentisic acid (HGA) and in a murine model has shown to prevent ochronosis. Little is currently known about the effect nitisinone has on osteoarticular cells; these cells suffer most from the presence of HGA and its polymeric derivatives. This led us to investigate nitisinone's effect on chondrocytes and osteoblast-like cells in an in vitro model. Human C20/A4 immortalized chondrocytes, and osteosarcoma cells MG63 cultured in DMEM, as previously described. Confluent cells were then plated into 24-well plates at 4 × 10(4) cells per well in varying concentrations of nitisinone. Cells were cultured for 7 days with medium changes every third day. Trypan blue assay was used to determine viability and the effect of nitisinone concentration on cells. Statistical analysis was performed using analysis of variance, and differences between groups were determined by Newman-Keuls post-test. Analysis of C20/A4 chondrocyte and MG63 osteoblast-like cell viability when cultured in different concentrations of nitisinone demonstrates that there is no statistically significant difference in cell viability compared to control cultures. There is currently no literature surrounding the use of nitisinone in human in vitro models, or its effect on chondrocytes or osteoblast like cells. Our results show that nitisinone does not appear detrimental to cell viability of chondrocytes or osteoblast-like cells, which adds to the evidence that this therapy could be useful in treating AKU.


Asunto(s)
4-Hidroxifenilpiruvato Dioxigenasa/antagonistas & inhibidores , Alcaptonuria/tratamiento farmacológico , Condrocitos/efectos de los fármacos , Ciclohexanonas/uso terapéutico , Nitrobenzoatos/uso terapéutico , Osteoblastos/efectos de los fármacos , Línea Celular Tumoral , Ciclohexanonas/farmacología , Evaluación Preclínica de Medicamentos , Humanos , Nitrobenzoatos/farmacología
2.
Int J Biol Macromol ; 82: 927-32, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26546869

RESUMEN

The macromolecule sodium lignosulfonate (SL) has been investigated as dispersing agent for aqueous alumina colloids as a renewable alternative to usual petrochemical stabilizing agents. Optimization of the SL concentration necessary to stabilize the alumina suspension at different pH values was determined by viscometer. The results showed that addition of 250 ppm of the total suspension mass led to about 70% viscosity reduction of the suspension, whereas zeta potential analysis revealed negative values for the SL suspensions throughout the pH range investigated, suggesting that the alumina particles were covered by negatively charged SL molecules. Particle size investigation informed that the average particle diameter of the SL suspensions was smaller compared to that of the pristine particles. Sedimentation time for the SL suspensions was dramatically longer than that for the pristine one. The reported data strongly corroborated that SL is a suitable renewable dispersing agent for aqueous alumina colloids.


Asunto(s)
Óxido de Aluminio/química , Lignina/análogos & derivados , Concentración de Iones de Hidrógeno , Lignina/química , Tamaño de la Partícula , Porosidad , Viscosidad
3.
Chem Sci ; 6(12): 7293-7304, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28757988

RESUMEN

A new set of [Cu(phen)2]+ based rotaxanes, featuring [60]-fullerene as an electron acceptor and a variety of electron donating moieties, namely zinc porphyrin (ZnP), zinc phthalocyanine (ZnPc) and ferrocene (Fc), has been synthesized and fully characterized with respect to electrochemical and photophysical properties. The assembly of the rotaxanes has been achieved using a slight variation of our previously reported synthetic strategy that combines the Cu(i)-catalyzed azide-alkyne cycloaddition reaction (the "click" or CuAAC reaction) with Sauvage's metal-template protocol. To underline our results, complementary model rotaxanes and catenanes have been prepared using the same strategy and their electrochemistry and photo-induced processes have been investigated. Insights into excited state interactions have been afforded from steady state and time resolved emission spectroscopy as well as transient absorption spectroscopy. It has been found that photo-excitation of the present rotaxanes triggers a cascade of multi-step energy and electron transfer events that ultimately leads to remarkably long-lived charge separated states featuring one-electron reduced C60 radical anion (C60˙-) and either one-electron oxidized porphyrin (ZnP˙+) or one-electron oxidized ferrocene (Fc˙+) with lifetimes up to 61 microseconds. In addition, shorter-lived charge separated states involving one-electron oxidized copper complexes ([Cu(phen)2]2+ (τ < 100 ns)), one-electron oxidized zinc phthalocyanine (ZnPc˙+; τ = 380-560 ns), or ZnP˙+ (τ = 2.3-8.4 µs), and C60˙- have been identified as intermediates during the sequence. Detailed energy diagrams illustrate the sequence and rate constants of the photophysical events occurring with the mechanically-linked chromophores. This work pioneers the exploration of mechanically-linked systems as platforms to position three distinct chromophores, which are able to absorb light over a very wide range of the visible region, triggering a cascade of short-range energy and electron transfer processes to afford long-lived charge separated states.

4.
S Afr Med J ; 104(12): 874-80, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26042271

RESUMEN

BACKGROUND: South Africa (SA) has the highest burden of childhood HIV infection globally, and has high rates of adolescent and youth pregnancy. OBJECTIVE: To explore risks associated with pregnancy in young HIV-infected women, we compared mother-to-child transmission (MTCT) of HIV and maternal and infant health outcomes according to maternal age categories. METHODS: A cohort of HIV-positive pregnant women and their infants were followed up at three sentinel surveillance facilities in the Nelson Mandela Bay Metropolitan (NMBM) district, Eastern Cape Province, SA. Young women were defined as 24 years old and adolescents as 19 years. The effect of younger maternal age categories on MTCT and maternal and child health outcomes was assessed using log-binomial and Cox regression controlling for confounding, using women aged > 24 years as the comparison group. RESULTS: Of 956 mothers, 312 (32.6%) were young women; of these, 65 (20.8%) were adolescents. The proportion of young pregnant women increased by 24% between 2009/10 and 2011/12 (from 28.3% to 35.1%). Young women had an increased risk of being unaware of their HIV status when booking (adjusted risk ratio (aRR) 1.37; 95% confidence interval (CI) 1.21 - 1.54), a reduced rate of antenatal antiretroviral therapy (ART) uptake (adjusted hazard ratio 0.46; 95% CI 0.31 - 0.67), reduced early infant HIV diagnosis (aRR 0.94; 95% CI 0.94 - 0.94), and increased MTCT (aRR 3.07; 95% CI 1.18 - 7.96; adjusted for ART use). Of all vertical transmissions, 56% occurred among young women. Additionally, adolescents had increased risks of first presentation during labour (aRR 3.78; 95% CI 1.06 - 13.4); maternal mortality (aRR 35.1; 95% CI 2.89 - 426) and stillbirth (aRR 3.33; 95% CI 1.53 - 7.25). CONCLUSION: An increasing proportion of pregnant HIV-positive women in NMBM were young, and they had increased MTCT and poorer maternal and infant outcomes than older women. Interventions targeting young women are increasingly needed to reduce pregnancy, HIV infection and MTCT and improve maternal and infant outcomes if SA is to attain its Millennium Development Goals.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/epidemiología , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo , Adolescente , Adulto , Factores de Edad , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/virología , Riesgo , Sudáfrica/epidemiología , Adulto Joven
5.
Int J Tuberc Lung Dis ; 17(10 Suppl 1): 48-55, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24020602

RESUMEN

OBJECTIVE: To conduct an impact assessment of an intervention to enhance the provision of community-based integrated services for tuberculosis (TB), human immunodeficiency virus (HIV) and prevention of mother-to-child transmission (PMTCT). METHODS: The intervention consisted of a combination of training of community care workers (CCWs), structural adjustments, harmonisation of scope of practice and stipend of CCWs and enhanced supervision of CCWs to provide comprehensive TB-HIV/PMTCT services in a rural South African district. A before and after study design was used with a household survey to assess the operational effectiveness of the intervention. Six clusters were randomised into intervention and control arms. Quantitative data were analysed using logistic regression, adjusting for cluster design. RESULTS: Logistic regression analyses of the survey data show that CCWs from the intervention arm performed better in the provision of TB-HIV/PMTCT services, such as screening for TB and sexually transmitted infections, adherence to anti-tuberculosis treatment and antiretroviral therapy and counselling on infant feeding compared to the control CCWs (P < 0.05). However, intervention CCWs performed worse in the integrated management of childhood illnesses education and social welfare referrals (P < 0.05). The uptake of HIV testing increased significantly in the intervention arm, from 55% to 78% (P < 0.001). CONCLUSION: The intervention was effective in enhancing the provision of community-based TB-HIV and PMTCT services. However, attention to other primary health care services is required to ensure that all key services are provided.


Asunto(s)
Servicios de Salud Comunitaria/organización & administración , Prestación Integrada de Atención de Salud/organización & administración , Infecciones por VIH/terapia , Tuberculosis/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/uso terapéutico , Antituberculosos/administración & dosificación , Antituberculosos/uso terapéutico , Análisis por Conglomerados , Estudios Transversales , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Modelos Logísticos , Masculino , Tamizaje Masivo/métodos , Cumplimiento de la Medicación , Persona de Mediana Edad , Embarazo , Población Rural , Sudáfrica , Tuberculosis/diagnóstico , Tuberculosis/prevención & control , Adulto Joven
6.
Environ Entomol ; 42(4): 658-67, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23905728

RESUMEN

Fungal entomopathogens are widely distributed across natural and managed systems, with numerous host species and likely a wide range of community impacts. While the potential for fungal pathogens to provide biological control has been explored in some detail, less is known about their community interactions. Here we investigate the effects of fungal epizootics of the entomopathogen Lecanicillium lecanii (Zimmerman) on a keystone mutualism between Azteca instabilis (F. Smith), a dominant arboreal ant, and the green coffee scale (Coccus viridis Green), as well as broader impacts on a coffee agroecosystem ant community. We hypothesized that seasonal epizootics cause shifts in the foraging ranges of A. instabilis as the ants adapt to the loss of the resource. We further hypothesized that the magnitude of these shifts depends on the availability of alternate resources located in neighboring shade trees. To test these hypotheses, we induced an epizootic in experimental sites, which were compared with control sites. Surveys of ant activity were undertaken pre- and post-epizootic. We found a decrease in foraging activity of A. instabilis and increase in activity of other ant species in the experimental sites post-epizootic. The decrease in abundance of A. instabilis foragers was greater on plants in which an epizootic was induced than in other plants. This relationship was modified by shade tree density where higher shade tree density was associated with larger decreases in A. intabilis foraging activity in coffee plants. These results demonstrate the potential for fungal entomopathogens to influence the structure and diversity of ecological communities.


Asunto(s)
Hormigas/fisiología , Biota , Hemípteros/microbiología , Hypocreales/fisiología , Simbiosis , Animales , Café/crecimiento & desarrollo , Ecosistema , Conducta Alimentaria , México , Densidad de Población
7.
J Endocrinol ; 217(1): R1-11, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23418361

RESUMEN

The melanocortin receptor (MCR) family consists of five G-protein-coupled receptors (MC1R-MC5R) with diverse physiological roles. MC1R controls pigmentation, MC2R is a critical component of the hypothalamic-pituitary-adrenal axis, MC3R and MC4R have a vital role in energy homeostasis and MC5R is involved in exocrine function. The melanocortin receptor accessory protein (MRAP) and its paralogue MRAP2 are small single-pass transmembrane proteins that have been shown to regulate MCR expression and function. In the adrenal gland, MRAP is an essential accessory factor for the functional expression of the MC2R/ACTH receptor. The importance of MRAP in adrenal gland physiology is demonstrated by the clinical condition familial glucocorticoid deficiency, where inactivating MRAP mutations account for ∼20% of cases. MRAP is highly expressed in both the zona fasciculata and the undifferentiated zone. Expression in the undifferentiated zone suggests that MRAP could also be important in adrenal cell differentiation and/or maintenance. In contrast, the role of adrenal MRAP2, which is highly expressed in the foetal gland, is unclear. The expression of MRAPs outside the adrenal gland is suggestive of a wider physiological purpose, beyond MC2R-mediated adrenal steroidogenesis. In vitro, MRAPs have been shown to reduce surface expression and signalling of all the other MCRs (MC1,3,4,5R). MRAP2 is predominantly expressed in the hypothalamus, a site that also expresses a high level of MC3R and MC4R. This raises the intriguing possibility of a CNS role for the MRAPs.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Glándulas Suprarrenales/embriología , Animales , Proteínas Portadoras/química , Regulación de la Expresión Génica , Humanos , Hipotálamo/metabolismo , Proteínas de la Membrana/química , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Receptores de Melanocortina/biosíntesis , Receptores de Melanocortina/química , Receptores de Melanocortina/metabolismo
8.
J Comput Assist Tomogr ; 36(6): 725-31, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23192211

RESUMEN

BACKGROUND: Radiation therapy can result in osteoradionecrosis (ORN) and mucosal ulceration predisposing to infection. METHODS: Fourteen patients presenting with infectious sequelae related to mandibular ORN were retrospectively reviewed. RESULTS: In most patients, infection followed diagnosis of ORN; but in 4 patients, ORN was not diagnosed until after the time of infection and imaging. An early imaging finding of ORN was lingual cortical defects near the last molar. Pain followed by erythema, purulent drainage, and subperiosteal abscess by imaging were the most common signs of infection. In most patients, conservative management eventually failed and segmental mandibulectomies were required. CONCLUSIONS: Soft tissue infection with characteristic bone findings such as subperiosteal abscess and cortical bone erosions helps to distinguish infected ORN from recurrent tumor or sterile ORN. In patients previously treated with radiation who present with infection, pain or an avid PET scan with bone involvement, the mandible should be scrutinized.


Asunto(s)
Enfermedades Óseas Infecciosas/diagnóstico por imagen , Enfermedades Mandibulares/diagnóstico por imagen , Osteorradionecrosis/complicaciones , Infecciones de los Tejidos Blandos/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Antiinfecciosos/uso terapéutico , Enfermedades Óseas Infecciosas/etiología , Enfermedades Óseas Infecciosas/terapia , Femenino , Estudios de Seguimiento , Humanos , Oxigenoterapia Hiperbárica/métodos , Masculino , Mandíbula/diagnóstico por imagen , Enfermedades Mandibulares/etiología , Enfermedades Mandibulares/terapia , Osteotomía Mandibular , Persona de Mediana Edad , Osteorradionecrosis/terapia , Dolor/etiología , Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Infecciones de los Tejidos Blandos/etiología , Infecciones de los Tejidos Blandos/terapia , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
9.
Clin Trials ; 7(6): 744-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20833684

RESUMEN

PURPOSE: To evaluate two recruitment strategies used during the full-scale randomized, placebo-controlled Selenium and Vitamin E Cancer Prevention Trial (SELECT) at one clinical center. BACKGROUND: Recruitment of participants to cancer prevention trials is challenging and costly and more efficient methods are needed. METHODS: SELECT participants were males ≥60 years old who were solicited with two recruitment strategies. In the control strategy, potential participants, identified through purchased mailing lists, were sent a SELECT invitation letter. In the 'spouse' strategy, letters were sent to married postmenopausal women already participating in the Women's Health Initiative (WHI) at our clinical center asking them to provide an enclosed SELECT invitation letter (identical to the one in the control strategy) to the 'man in her life'. Our hypothesis was that SELECT recruitment of men would be enhanced by this indirect mailing to their spouses already participating in a similar program. RESULTS: In the control strategy, 183,315 invitation letters were mailed to 60,000 men; cumulative response was 2.16%; 600 men ultimately enrolled in SELECT (15.1% of respondents) for a mailing recruitment cost of $259 per participant. In the spouse strategy, 800 women participating in WHI clinical studies had husbands; of the 2214 invitation letters mailed to this group of women, cumulative response was 2.75%; 34 men ultimately enrolled in SELECT (55.7% of respondents) for a mailing recruitment cost of $59 per participant. LIMITATION: Process information on how invitation letters were handled in the spouse strategy was not collected. CONCLUSION: A direct mail recruitment strategy was successful in recruiting men to a cancer prevention trial. A recruitment strategy involving indirect mailing to married women participating in a similar research program in the same center did not increase initial response substantially, but a higher proportion of respondents ultimately entered the prevention trial.


Asunto(s)
Antioxidantes/uso terapéutico , Selección de Paciente , Neoplasias de la Próstata/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Selenio/uso terapéutico , Vitamina E/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
10.
Water Sci Technol ; 62(3): 510-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20705997

RESUMEN

The bulk and retail water companies of the greater Melbourne area are developing the 2009 Metropolitan Sewerage Strategy to provide sustainable sewerage services to 2060. The objective of the strategy is to establish long term principles and near term actions to produce a robust sewage management system for Melbourne. Melbourne's existing sewerage system is largely centralised and discharges to two major treatment plants. Several small satellite treatment plants service local urban areas generally more distant from the centralised system. Decentralised and on-site wastewater systems are options for future sewage management and could play a role in local recycling. A portfolio of 18 on-site and decentralised concept designs was developed, applicable to the full range of urban development types in Melbourne. The concepts can be used in evaluation of metropolitan system configurations as part of future integrated water cycle planning. The options included secondary and tertiary treatment systems incorporating re-use of water for non potable uses, urine separation, black and greywater separation and composting toilets. On-site and cluster treatment systems were analysed. Each option is described by its indicative capital and operating costs, energy use and water and nutrient balances. This paper summarises and compares the portfolio mix of decentralized and on-site options in Melbourne's context.


Asunto(s)
Ciudades , Ingeniería Sanitaria/métodos , Aguas del Alcantarillado , Conservación de los Recursos Naturales/métodos , Fuentes Generadoras de Energía/economía , Vivienda , Humanos , Nitrógeno/química , Fósforo/química , Ingeniería Sanitaria/economía , Ingeniería Sanitaria/tendencias , Victoria , Contaminantes del Agua , Contaminación del Agua/prevención & control
11.
Neurotoxicol Teratol ; 32(2): 171-81, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19818397

RESUMEN

Consuming omega-3 fatty acids (omega-3 FA) during pregnancy and lactation is beneficial to fetal and infant development and might reduce the incidence and severity of preterm births by prolonging pregnancy. Consequently, supplementing maternal diets with large amounts of omega-3 FA is gaining acceptance. However, both over- and under-supplementation with omega-3 FA can harm offspring development. Adverse fetal and neonatal conditions in general can enhance age-related neural degeneration, shorten life span and cause other adult-onset disorders. We hypothesized that maternal over- and under-nutrition with omega-3 FA would shorten the offspring's life span and enhance neural degeneration in old adulthood. To test these hypotheses, female Wistar rats were randomly assigned to one of the three diet conditions starting from day 1 of pregnancy through the entire period of pregnancy and lactation. The three diets were Control omega-3 FA (omega-3/omega-6 ratio approximately 0.14), Excess omega-3 FA (omega-3/omega-6 ratio approximately 14.5) and Deficient omega-3 FA (omega-3/omega-6 ratio approximately 0% ratio). When possible, one male and female offspring from each litter were assessed for life span and sensory/neural degeneration (n=15 litters/group). The Excess offspring had shorter life spans compared to their Control and Deficient cohorts (mean+/-SEM=506+/-24, 601+/-14 and 585+/-21 days, p

Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Ácidos Grasos Omega-3/toxicidad , Longevidad/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Envejecimiento/patología , Envejecimiento/fisiología , Animales , Vías Auditivas/efectos de los fármacos , Vías Auditivas/fisiopatología , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Encéfalo/crecimiento & desarrollo , Grasas de la Dieta/toxicidad , Modelos Animales de Enfermedad , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Femenino , Lactancia/efectos de los fármacos , Lactancia/metabolismo , Longevidad/fisiología , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/patología , Presbiacusia/inducido químicamente , Presbiacusia/fisiopatología , Ratas , Ratas Wistar , Tiempo
12.
Neurotoxicol Teratol ; 31(1): 26-33, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18834936

RESUMEN

Consuming omega-3 fatty acids (omega-3 FA) during pregnancy and lactation benefits fetal and infant brain development and might reduce the severity of preterm births by prolonging pregnancy. However, diets that are relatively rich in omega-3 FA can adversely affect fetal and infant development and the auditory brainstem response (ABR), a measure of brain development and sensory function. We previously examined the offspring of female rats fed excessive, adequate or deficient amounts of omega-3 FA during pregnancy and lactation. The 24-day-old offspring in the Excess group, compared to the Control group, had postnatal growth retardation and poor hearing acuity and prolonged neural transmission times as evidenced by the ABR. The Deficient group was intermediate. The current study followed these offspring to see if these poor outcomes persisted into young adulthood. Based on prior findings, we hypothesized that the Excess and Deficient offspring would "catch-up" to the Control offspring by young adulthood. Female Wistar rats received one of the three diet conditions from day 1 of pregnancy through lactation. The three diets were the Control omega-3 FA condition (omega-3/omega-6 ratio approximately 0.14), the Excess omega-3 FA condition (omega-3/omega-6 ratio approximately 14.0) and Deficient omega-3 FA condition (omega-3/omega-6 ratio approximately 0% ratio). The Control diet contained 7% soybean oil; whereas the Deficient and Excess omega-3 FA diets contained 7% safflower oil and 7% fish oil, respectively. One male and female offspring per litter were ABR-tested as young adults using tone pip stimuli of 2, 4, 8 and 16 kHz. The postnatal growth retardation and prolonged neural transmission times in the Excess and Deficient pups had dissipated by young adulthood. In contrast, the Excess group had elevated ABR thresholds (hearing loss) at all tone pip frequencies in comparison to the Control and Deficient groups. The Deficient group had worse ABR thresholds than the Control group in response to the 8 kHz tone pips only. The Excess group also had ABR amplitude-intensity profiles suggestive of hyperacusis. These results are consistent with the Barker hypothesis concerning the fetal and neonatal origins of adult diseases. Thus, consuming diets that are excessively rich or deficient in omega-3 FA during pregnancy and lactation seems inadvisable because of risks for long-lasting adverse effects on brain development and sensory function.


Asunto(s)
Ácidos Grasos Omega-3/toxicidad , Lactancia/fisiología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Envejecimiento/psicología , Análisis de Varianza , Animales , Dieta , Electrodos , Femenino , Audición/efectos de los fármacos , Audición/fisiología , Masculino , Embarazo , Resultado del Embarazo , Efectos Tardíos de la Exposición Prenatal/psicología , Ratas , Ratas Wistar , Umbral Sensorial/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología
13.
J Environ Radioact ; 73(1): 29-48, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15001294

RESUMEN

Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of (99)Tc, as a result of the treatment of previously stored waste, with consequent increases in (99)Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of (99)Tc and (137)Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of (99)Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of (99)Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg(-1) (fresh weight (fw)) in crabs and 124 to 216 Bq kg(-1) (fw) in lobsters, with no observed seasonal variations. Activity concentrations of (137)Cs in both crab and lobster were lower, ranging from <0.16 to 0.85 Bq kg(-1) for crab meat (fw) and <0.3 to 3.3 Bq kg(-1) for lobster meat (fw). A statistically significant increase in activity concentrations of (137)Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves during the active feeding period over the summer. At all times, uptake of (99)Tc is higher in the brown meat fraction of both crabs and lobsters, whilst (137)Cs is more uniformly distributed. These results are used to discuss the implications for sampling and monitoring programmes.


Asunto(s)
Braquiuros , Cesio/farmacocinética , Nephropidae , Tecnecio/farmacocinética , Contaminantes Radiactivos del Agua/farmacocinética , Animales , Cesio/análisis , Radioisótopos de Cesio/análisis , Radioisótopos de Cesio/farmacocinética , Monitoreo del Ambiente , Contaminación de Alimentos , Irlanda , Movimiento , Dinámica Poblacional , Alimentos Marinos , Estaciones del Año , Tecnecio/análisis , Distribución Tisular , Contaminantes Radiactivos del Agua/análisis
14.
Drug Metab Dispos ; 31(11): 1382-90, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14570771

RESUMEN

Assessment of the pharmacokinetics of [14C]2-[3-[3-[(5-ethyl-4'-fluoro-2-hydroxy[1,1'-biphenyl]-4-yl)oxy]propoxy]-2-propylphenoxy-]benzoic acid ([14C]LY293111), an experimental anti-cancer agent, suggested long-lived circulating metabolites in rats. In vivo metabolites of LY293111 were examined in plasma, bile, urine, and feces of Fischer 344 (F344) rats after oral administration of [14C]LY293111. Metabolites were profiled by high-performance liquid chromatography-radiochromatography, and identified by liquid chromatography (LC)/mass spectrometry and LC/NMR. The major in vivo metabolites of LY293111 identified in rats were phenolic (ether), acyl, and bisglucuronides of LY293111. Measurement of radioactivity in rat plasma confirmed that a fraction of LY293111-derived material was irreversibly bound to plasma protein and that this bound fraction increased over time. This was consistent with the observed disparity in half-lives between LY293111 and total radioactivity in rats and monkeys, and is likely due to covalent modification of proteins by the acyl glucuronide. In vitro metabolism of [14C]LY293111 in liver slices from CD-1 mice, F344 rats, rhesus and cynomolgus monkeys, and humans indicates that glucuronidation was the primary metabolic pathway in all species. The acyl glucuronide was the most prevalent radioactive peak (16% of total 14C) produced by F344 rat slices, whereas the ether glucuronide was the major metabolite in all other species (26-36% of total 14C). Several minor hydroxylated metabolites were detected in F344 rat slice extracts but were not observed in other species. The data presented suggest that covalent modification of proteins by LY293111 acyl glucuronide is possible in multiple species, although the relative reactivity of this metabolite appears to be low compared with those known to cause adverse drug reactions.


Asunto(s)
Benzoatos/sangre , Benzoatos/farmacocinética , Animales , Benzoatos/química , Evaluación Preclínica de Medicamentos/métodos , Femenino , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Macaca fascicularis , Macaca mulatta , Masculino , Ratones , Persona de Mediana Edad , Ratas , Ratas Endogámicas F344 , Especificidad de la Especie
15.
Stat Med ; 21(20): 3023-33, 2002 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-12369079

RESUMEN

In a complex seven-period cross-over trial to study the effects of a drug in attenuating capsaicin-induced coughing, counts of numbers of coughs were recorded 32 times in each period. Subjects were subjected to four escalating levels of capsaicin at each of one and five hours after treatment, with counts of coughs being recorded in four one-minute intervals at each level. Such longitudinal count studies often show considerable individual variability about any regression curve that might be fitted. We develop a non-linear autoregressive model for such count data that also allows for overdispersion.


Asunto(s)
Tos/tratamiento farmacológico , Estudios Cruzados , Modelos Estadísticos , Tiazoles/farmacología , Agonistas Adrenérgicos beta/farmacología , Albuterol/farmacología , Capsaicina/administración & dosificación , Tos/inducido químicamente , Domperidona/farmacología , Antagonistas de Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Estudios Longitudinales , Masculino , Receptores de Dopamina D2/agonistas
16.
Int J Vitam Nutr Res ; 71(5): 293-301, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11725694

RESUMEN

The effectiveness of a nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogens from the ingested androgens was investigated in healthy 30- to 59-year old men. Subjects were randomly assigned to consume DION (300 mg androstenedione, 150 mg dehydroepiandrosterone, 540 mg saw palmetto, 300 mg indole-3-carbinol, 625 mg chrysin, and 750 mg Tribulus terrestris per day; n = 28) or placebo (n = 27) for 28 days. Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured before and throughout the 4-week supplementation period. Serum concentrations of total testosterone and PSA were unchanged by supplementation. DION increased (p < 0.05) serum androstenedione (342%), free testosterone (38%), dihydrotestosterone (71%), and estradiol (103%) concentrations. Serum HDL-C concentrations were reduced by 5.0 mg/dL in DION (p < 0.05). Increases in serum free testosterone (r2 = 0.01), androstenedione (r2 = 0.01), dihydrotestosterone (r2 = 0.03), or estradiol (r2 = 0.07) concentrations in DION were not related to age. While the ingestion of androstenedione combined with herbal products increased serum free testosterone concentrations in older men, these herbal products did not prevent the conversion of ingested androstenedione to estradiol and dihydrotestosterone.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Androstenodiona/uso terapéutico , Deshidroepiandrosterona/uso terapéutico , Suplementos Dietéticos , Hormonas Esteroides Gonadales/sangre , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Adulto , Factores de Edad , Análisis de Varianza , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Testosterona/sangre
17.
J Am Coll Nutr ; 20(5): 520-8, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11601567

RESUMEN

OBJECTIVE: The effectiveness of an androgenic nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogen was investigated in healthy 3 to 58 year old men. DESIGN: Subjects were randomly assigned to consume a nutritional supplement (AND-HB) containing 300-mg androstenediol, 480-mg saw palmetto, 450-mg indole-3-carbinol, 300-mg chrysin, 1,500 mg gamma-linolenic acid and 1.350-mg Tribulus terrestris per day (n = 28), or placebo (n = 27) for 28 days. Subjects were stratified into age groups to represent the fourth (30 year olds, n = 20), fifth (40 year olds, n = 20) and sixth (50 year olds, n = 16) decades of life. MEASUREMENTS: Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate specific antigen and lipid concentrations were measured before supplementation and weekly for four weeks. RESULTS: Basal serum total testosterone, estradiol, and prostate specific antigen (PSA) concentrations were not different between age groups. Basal serum free testosterone concentrations were higher (p < 0.05) in the 30- (70.5 +/- 3.6 pmol/L) than in the 50 year olds (50.8 +/- 4.5 pmol/L). Basal serum androstenedione and dihydrotestosterone (DHT) concentrations were significantly higher in the 30- (for androstenedione and DHT, respectively, 10.4 +/- 0.6 nmol/L and 2198.2 +/- 166.5 pmol/L) than in the 40- (6.8 +/- 0.5 nmol/L and 1736.8 +/- 152.0 pmol/L) or 50 year olds (6.0 +/- 0.7 nmol/L and 1983.7 +/- 147.8 pmol/L). Basal serum hormone concentrations did not differ between the treatment groups. Serum concentrations of total testosterone and PSA were unchanged by supplementation. Ingestion of AND-HB resulted in increased (p < 0.05) serum androstenedione (174%), free testosterone (37%), DHT (57%) and estradiol (86%) throughout the four weeks. There was no relationship between the increases in serum free testosterone, androstenedione, DHT, or estradiol and age (r2 = 0.08, 0.03, 0.05 and 0.02, respectively). Serum HDL-C concentrations were reduced (p < 0.05) by 0.14 mmol/L in AND-HB. CONCLUSIONS: These data indicate that ingestion of androstenediol combined with herbal products does not prevent the formation of estradiol and dihydrotestosterone.


Asunto(s)
Anabolizantes/administración & dosificación , Androstenodiol/administración & dosificación , Suplementos Dietéticos , Estradiol/sangre , Testosterona/sangre , Administración Oral , Adulto , Factores de Edad , Androstenodiona/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Placebos , Antígeno Prostático Específico/sangre , Factores de Tiempo
18.
Clin Orthop Relat Res ; (391 Suppl): S14-25, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11603698

RESUMEN

The symptomatic degeneration of articular cartilage and associated arthritis is among the most prevalent chronic conditions in the United States and the population most at risk is increasing. It is the leading cause of limitations in activities of daily living and is second to heart disease in causing work disability. The current and future socioeconomic impact of chronic articular cartilage disease on the healthcare system will be magnified by increasing numbers of patients who will seek relief of their symptoms and their disability to remain active. Because these individuals live longer and remain active, the proportion of their life living with symptoms and disability from articular cartilage degeneration increases. The economic, psychologic, and social impact of degenerative articular cartilage can be enormous for these individuals but it also impacts their family and society. The direct traditional medical costs and indirect economic and wage loss from arthritis in individuals the United States has reached in excess of $65 billion annually and is expected to increase as the population ages. In addition, the expenditures for complementary and alternative professional services and therapies for arthritis is increasing and is also in the billions of dollars annually. Because of these escalating costs, documenting the value of the patient and cost effectiveness to society of prevention and treatment programs for symptomatic articular cartilage degeneration will be required.


Asunto(s)
Cartílago Articular , Osteoartritis/diagnóstico , Terapias Complementarias , Predicción , Costos de la Atención en Salud , Humanos , Osteoartritis/economía , Osteoartritis/epidemiología , Osteoartritis/terapia , Factores de Riesgo
19.
Environ Pollut ; 112(1): 53-60, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11202654

RESUMEN

Phosphorus (P) surface run-off losses were studied following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farm yard manure (FYM) and inorganic nitrogen (N) and P fertiliser were compared, over a 4-year period (1993-97). N losses from the same studies are reported in a separate paper. The application of cattle FYM and, especially slurry, to the silty clay loam soil increased both particulate and soluble P loss in surface water flow. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increased application of slurry solids increased all forms of P loss via surface run-off; the results suggested that a threshold for greatly increased risk of P losses via this route, as for N, occurred at ca. 2.5-3.0 t/ha solids loading. This approximates to the 50 m3/ha application rate limit suggested for slurry within UK 'good agricultural practice'. The studies also provided circumstantial evidence of the sealing of the soil surface by slurry solids as the major mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Losses of total and soluble P, recorded for each of the 4 years of experiments, reached a maximum of only up to 2 kg/ha total P (TP), even after slurry applications initiating run-off. Whilst these losses are insignificant in agronomic terms, peak concentrations of P (up to 30,000 micrograms/l TP) in surface water during a run-off event, could be of considerable concern in sensitive catchments. Losses of slurry P via surface run-off could make a significant contribution to accelerated eutrophication on entry to enclosed waters, particularly when combined with high concentrations of NO3(-)-N. Restricting slurry application rates to those consistent with good agronomic practice, and within the limits specified in existing guidelines on good agricultural practice, offers the simplest and most effective control measure against this potentially important source of diffuse pollution.


Asunto(s)
Agricultura , Estiércol , Fósforo/química , Contaminantes del Agua , Agricultura/métodos , Animales , Bovinos , Inglaterra , Agua Dulce
20.
J Clin Endocrinol Metab ; 85(11): 4074-80, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11095435

RESUMEN

In young men, chronic ingestion of 100 mg androstenedione (ASD), three times per day, does not increase serum total testosterone but does increase serum estrogen and ASD concentrations. We investigated the effects of ASD ingestion in healthy 30- to 56-yr-old men. In a double-blind, randomly assigned manner, subjects consumed 100 mg ASD three times daily (n = 28), or placebo (n = 27) for 28 days. Serum ASD, dihydrotestosterone (DHT), free and total testosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured at week 0 and each week throughout the supplementation period. Serum total testosterone and PSA concentrations did not change with supplementation. Elevated serum concentrations of ASD (300%), free testosterone (45%), DHT (83%), and estradiol (68%) were observed during weeks 1-4 in ASD (P < 0.05). There was no relationship between age and changes in serum ASD (r2 = 0.024), free testosterone (r2 = 0.00), or estradiol (r2 = 0.029) concentrations with ASD, whereas the serum DHT response to ASD ingestion was related to age (r2 = 0.244; P < 0.05). Serum concentrations of high-density lipoprotein cholesterol were decreased by 10% during the supplementation period (P < 0.05). These results suggest that the ingestion of 100 mg ASD, three times per day, does not increase serum total testosterone or PSA concentrations but does elicit increases in ASD, free testosterone, estradiol, and DHT and decreases serum high-density lipoprotein cholesterol concentrations.


Asunto(s)
Afecto , Androstenodiona/sangre , Androstenodiona/farmacología , Testosterona/sangre , Administración Oral , Adulto , Factores de Edad , Androstenodiona/administración & dosificación , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Estradiol/sangre , Humanos , Masculino , Persona de Mediana Edad , Placebos , Antígeno Prostático Específico/sangre , Factores de Tiempo
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