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1.
J Womens Health (Larchmt) ; 33(7): 870-878, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38465503

RESUMEN

Background: Symptoms of mental distress increased sharply during the COVID-19 pandemic, especially among older adolescents and young adults. Mental health distress may make it more challenging for young people to seek other needed health care, including contraception. This study explored the association of symptoms of depression, anxiety, and stress with delays in getting a contraceptive method or prescription. Materials and Methods: Data from a supplementary study (May 15, 2020-March 20, 2023) to a cluster randomized trial in 29 sites in Texas and California were used. The diverse study sample included community college students assigned female at birth of ages 18-29 years (n = 1,665 with 7,023 observations over time). We measured the association of depression (CES-D [Center for Epidemiologic Studies Depression Scale]) or anxiety and stress (DASS-21 [Depression Anxiety Stress Scales]) symptoms with delayed contraceptive care-seeking with mixed-effects multivariable regression with random effects for individual and site. We controlled for age and sociodemographic factors important for access to care. Results: Over one-third of participants (35%) reported they delayed getting the contraceptive method they needed. Multivariable regression results showed increased odds of delayed contraceptive care among participants with symptoms of depression (adjusted odds ratio [aOR] 1.58, 95% confidence interval [CI] 1.27-1.96). Likewise, delays were associated with anxiety and stress symptoms (aOR 1.46, 95% CI 1.17-1.82). Adolescents were more likely to delay seeking contraception than young adults (aOR 1.32, 95% CI 1.07-1.63). Conclusions: Results showed a strong association between mental distress and delayed contraception. Interventions are needed to increase contraceptive access for young people delaying care, along with supportive mental health care services, including for adolescents who face elevated odds of delay. ClinicalTrials.gov Identifier: NCT03519685.


Asunto(s)
Ansiedad , Depresión , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Depresión/epidemiología , Ansiedad/epidemiología , Aceptación de la Atención de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/psicología , Estrés Psicológico/epidemiología , COVID-19/psicología , COVID-19/epidemiología , California/epidemiología , Texas/epidemiología , Anticoncepción/estadística & datos numéricos , Anticoncepción/psicología , Salud Mental/estadística & datos numéricos , Distrés Psicológico , SARS-CoV-2 , Accesibilidad a los Servicios de Salud/estadística & datos numéricos
2.
Nat Commun ; 12(1): 4551, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34315879

RESUMEN

Cornelia de Lange syndrome (CdLS) is a rare disease affecting multiple organs and systems during development. Mutations in the cohesin loader, NIPBL/Scc2, were first described and are the most frequent in clinically diagnosed CdLS patients. The molecular mechanisms driving CdLS phenotypes are not understood. In addition to its canonical role in sister chromatid cohesion, cohesin is implicated in the spatial organization of the genome. Here, we investigate the transcriptome of CdLS patient-derived primary fibroblasts and observe the downregulation of genes involved in development and system skeletal organization, providing a link to the developmental alterations and limb abnormalities characteristic of CdLS patients. Genome-wide distribution studies demonstrate a global reduction of NIPBL at the NIPBL-associated high GC content regions in CdLS-derived cells. In addition, cohesin accumulates at NIPBL-occupied sites at CpG islands potentially due to reduced cohesin translocation along chromosomes, and fewer cohesin peaks colocalize with CTCF.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Síndrome de Cornelia de Lange/genética , Genoma Humano , Transcriptoma/genética , Diferenciación Celular/genética , Cromatina/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Estabilidad Proteica , Cohesinas
3.
Cell Death Dis ; 11(2): 82, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-32015347

RESUMEN

The long isoform of Fas apoptosis inhibitory molecule (FAIM-L) is a neuron-specific death receptor antagonist that modulates apoptotic cell death and mechanisms of neuronal plasticity. FAIM-L exerts its antiapoptotic action by binding to X-linked inhibitor of apoptosis protein (XIAP), an inhibitor of caspases, which are the main effectors of apoptosis. XIAP levels are regulated by the ubiquitin-proteasome pathway. FAIM-L interaction with XIAP prevents the ubiquitination and degradation of the latter, thereby allowing it to inhibit caspase activation. This interaction also modulates non-apoptotic functions of caspases, such as the endocytosis of AMPA receptor (AMPAR) in hippocampal long-term depression (LTD). The molecular mechanism of action exerted by FAIM-L is unclear since the consensus binding motifs are still unknown. Here, we performed a two-hybrid screening to discover novel FAIM-L-interacting proteins. We found a functional interaction of SIVA-1 with FAIM-L. SIVA-1 is a proapoptotic protein that has the capacity to interact with XIAP. We describe how SIVA-1 regulates FAIM-L function by disrupting the interaction of FAIM-L with XIAP, thereby promoting XIAP ubiquitination, caspase-3 activation and neuronal death. Furthermore, we report that SIVA-1 plays a role in receptor internalization in synapses. SIVA-1 is upregulated upon chemical LTD induction, and it modulates AMPAR internalization via non-apoptotic activation of caspases. In summary, our findings uncover SIVA-1 as new functional partner of FAIM-L and demonstrate its role as a regulator of caspase activity in synaptic function.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis , Proteínas Inhibidoras de la Apoptosis/metabolismo , Plasticidad Neuronal , Animales , Proteínas Reguladoras de la Apoptosis/genética , Caspasa 3/metabolismo , Células Cultivadas , Células HEK293 , Hipocampo/citología , Hipocampo/metabolismo , Humanos , Ratones , N-Metilaspartato/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Células PC12 , Unión Proteica , Ratas , Receptores AMPA/metabolismo , Ubiquitinación
4.
Rev Med Inst Mex Seguro Soc ; 46(6): 591-6, 2008.
Artículo en Español | MEDLINE | ID: mdl-19263661

RESUMEN

OBJECTIVE: To compare the correlation between C reactive protein (CRP) and erythrosedimentation rate (ESR) with rheumatoid arthritis (RA) activity. METHODS: Cross-sectional study, in patients with RA. All were assessed by a rheumatologist who evaluated the RA disease activity according to the American College of Rheumatology score. Blood sample was dropped to test CRP and ESR levels. The correlation between CRP and ESR with RA disease activity was estimated using rho Spearman coefficient. RESULTS: We included 80 patients, mean age of 50.5 +/- 11.0 years. 62.5% had some degree of disease activity. We found that CRP had a high correlation with all parameters of disease activity included: number of tenders joins (r = 0.352, p = 0.001), number of painful joins (r = 0.327, p = 0.003), VAS of join pain (r = 0.385, p < 0.0001), VAS of global disease activity estimated by the patient (r = 0.325, p = 0.003), VAS of global disease activity estimated by the rheumatologist (r = 0.486, p < 0.0001), and HAQ score (r = 0.310, p= 0.005). In contrast the ESR only had correlation with the HAQ score (r = 0.310, p = 0.005). CONCLUSIONS: Our results suggest that CRP is a better test to support the clinical evaluation of disease activity in RA.


Asunto(s)
Artritis Reumatoide/sangre , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
5.
Gac. méd. Méx ; 157(supl.3): S55-S67, feb. 2021. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1375504

RESUMEN

Resumen La propagación tan rápida del nuevo coronavirus 2 del síndrome respiratorio agudo grave (SARS-CoV-2), que se informó por primera vez en Wuhan (China) a finales de diciembre de 2019, y produce la enfermedad caracterizada por neumonía llamada enfermedad por coronavirus 2019 (COVID-19), ha causado un impacto significativo en los sistemas de salud en todo el mundo y la interrupción de la vida cotidiana. A finales de junio el número de casos confirmados es de 9,188,362 millones, con más de 474,339 muertes, y aproximadamente 4,937,282 personas recuperadas. Las estrictas medidas para restricción de la movilidad y medidas de distanciamiento social impuestas por los gobiernos, más el miedo y pánico resultado de manera abrumadora entre el público general, ha comprometido de manera importante la sostenibilidad del suministro de sangre segura, el cual se vuelve particularmente desafiante. La demanda de sangre y productos sanguíneos puede disminuir durante una pandemia debido al aplazamiento de cirugías electivas. Medidas como el distanciamiento físico y el bloqueo total de las ciudades, las provincias o países que intentan frenar la propagación de la infección pueden provocar una disminución importante en el suministro y una escasez general de productos sanguíneos. Los hospitales deben contar con un plan de manejo de sangre para emergencias en la planificación de preparación sobre la sostenibilidad y seguridad del suministro de sangre. Esta revisión considera el impacto de la pandemia de COVID-19 en el suministro de sangre y especifica aspectos importantes del manejo de los donantes, y la utilización apropiada de los componentes sanguíneos.


Abstract The rapid spread of the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was first reported in Wuhan (China) in late December 2019, and produces the disease characterized by pneumonia called coronavirus disease 2019 (COVID-19), has caused a significant impact on health systems worldwide and disruption of daily life; at the end of June the number of confirmed cases is 9,188,362 million with more than 474,339 deaths, and approximately 4,937,282 people recovered. Strict measures to restrict mobility, social distancing measures imposed by governments, plus overwhelming fear and panic among the general public, have significantly compromised the sustainability of the safe blood supply, it becomes particularly challenging. The demand for blood and blood products may decrease during a pandemic due to the postponement of elective surgeries, measures such as physical distancing and the total blockade of cities, provinces or countries that try to stop the spread of the infection can cause a significant decrease in the supply and a general shortage of blood products. Hospitals must have a blood management plan for emergencies in preparedness planning on the sustainability and safety of the blood supply. This review considers the impact of the COVID-19 pandemic on blood supply and specifies important aspects of donor management, and the proper use of blood components.

6.
Nat Commun ; 7: 11581, 2016 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-27181366

RESUMEN

Cyclin D1 (Ccnd1) together with its binding partner Cdk4 act as a transcriptional regulator to control cell proliferation and migration, and abnormal Ccnd1·Cdk4 expression promotes tumour growth and metastasis. While different nuclear Ccnd1·Cdk4 targets participating in cell proliferation and tissue development have been identified, little is known about how Ccnd1·Cdk4 controls cell adherence and invasion. Here, we show that the focal adhesion component paxillin is a cytoplasmic substrate of Ccnd1·Cdk4. This complex phosphorylates a fraction of paxillin specifically associated to the cell membrane, and promotes Rac1 activation, thereby triggering membrane ruffling and cell invasion in both normal fibroblasts and tumour cells. Our results demonstrate that localization of Ccnd1·Cdk4 to the cytoplasm does not simply act to restrain cell proliferation, but constitutes a functionally relevant mechanism operating under normal and pathological conditions to control cell adhesion, migration and metastasis through activation of a Ccnd1·Cdk4-paxillin-Rac1 axis.


Asunto(s)
Ciclina D1/metabolismo , Citoplasma/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Paxillin/metabolismo , Animales , Línea Celular Tumoral , Membrana Celular/metabolismo , Ciclina D1/deficiencia , Quinasa 4 Dependiente de la Ciclina/metabolismo , Regulación hacia Abajo/genética , Fibroblastos/metabolismo , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Ratones , Invasividad Neoplásica , Metástasis de la Neoplasia , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Ratas , Especificidad por Sustrato , Proteína de Unión al GTP rac1/metabolismo
7.
Oncotarget ; 7(19): 26979-91, 2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27105504

RESUMEN

Cyclin D1 (Ccnd1) is a proto-oncogen amplified in many different cancers and nuclear accumulation of Ccnd1 is a characteristic of tumor cells. Ccnd1 activates the transcription of a large set of genes involved in cell cycle progress and proliferation. However, Ccnd1 also targets cytoplasmic proteins involved in the regulation of cell migration and invasion. In this work, we have analyzed by immunohistochemistry the localization of Ccnd1 in endometrial, breast, prostate and colon carcinomas with different types of invasion. The number of cells displaying membranous or cytoplasmic Ccnd1 was significantly higher in peripheral cells than in inner cells in both collective and pushing invasion patterns of endometrial carcinoma, and in collective invasion pattern of colon carcinoma. Also, the cytoplasmic localization of Ccnd1 was higher when tumors infiltrated as single cells, budding or small clusters of cells. To evaluate cytoplasmic function of cyclin D1, we have built a variant (Ccnd1-CAAX) that remains attached to the cell membrane therefore sequestering this cyclin in the cytoplasm. Tumor cells harboring Ccnd1-CAAX showed high levels of invasiveness and metastatic potential compared to those containing the wild type allele of Ccnd1. However, Ccnd1-CAAX expression did not alter proliferative rates of tumor cells. We hypothesize that the role of Ccnd1 in the cytoplasm is mainly associated with the invasive capability of tumor cells. Moreover, we propose that subcellular localization of Ccnd1 is an interesting guideline to measure cancer outcome.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Ciclina D1/metabolismo , Citoplasma/metabolismo , Neoplasias/metabolismo , Secuencias de Aminoácidos/genética , Animales , Biomarcadores de Tumor/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Membrana Celular/metabolismo , Células Cultivadas , Neoplasias del Colon/metabolismo , Ciclina D1/genética , Neoplasias Endometriales/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones Desnudos , Ratones SCID , Microscopía Confocal , Invasividad Neoplásica , Neoplasias de la Próstata/metabolismo
8.
Psychopharmacology (Berl) ; 178(4): 431-9, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15765258

RESUMEN

RATIONALE: In adult rats, the partial D(2)-like agonist terguride acts as an antagonist at normosensitive D(2)-like post-synaptic receptors, while it acts as an agonist at the same receptors during states of low dopaminergic tone. OBJECTIVE: The purpose of the present study was to determine whether partial D(2)-like agonists exhibit both antagonistic and agonistic actions during the preweanling period. METHODS: In experiments 1 and 2 (examining the agonistic actions of terguride), preweanling rats were either given an escalating regimen of amphetamine to induce a state of amphetamine withdrawal or pretreated with the tyrosine hydroxylase inhibitor AMPT. Distance traveled was measured after rats were injected with saline, terguride (0.4-1.6 mg/kg), or the full D(2)-like receptor agonist NPA (0.01 mg/kg). In experiment 3 (examining the antagonistic actions of terguride), preweanling rats were pretreated with terguride 30 min before they were tested with saline, NPA (0.05 mg/kg), or amphetamine (1.5 mg/kg). RESULTS: NPA had an exaggerated locomotor activating effect when tested under conditions of amphetamine withdrawal, while the partial D(2)-like agonist did not enhance distance traveled under any circumstance. Similarly, NPA increased and terguride did not affect the distance-traveled scores of AMPT-pretreated rats. In experiment 3, terguride pretreatment significantly reduced the distance traveled of amphetamine-treated and NPA-treated rats. CONCLUSIONS: The behavioral evidence indicates that, during the preweanling period, terguride antagonizes D(2)-like post-synaptic receptors in a state of high dopaminergic tone; however, there is no evidence that terguride is capable of stimulating D(2)-like post-synaptic receptors during states of low dopaminergic tone.


Asunto(s)
Antagonistas de Dopamina/farmacología , Dopamina/fisiología , Lisurida/análogos & derivados , Receptores de Dopamina D2/administración & dosificación , Receptores de Dopamina D2/agonistas , Animales , Animales Recién Nacidos , Apomorfina/efectos adversos , Apomorfina/análogos & derivados , Apomorfina/farmacología , Peso Corporal/efectos de los fármacos , Cuerpo Estriado/química , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Dextroanfetamina/administración & dosificación , Dextroanfetamina/efectos adversos , Dextroanfetamina/metabolismo , Antagonistas de los Receptores de Dopamina D2 , Hipercinesia/inducido químicamente , Lisurida/farmacología , Metiltirosinas/administración & dosificación , Metiltirosinas/farmacocinética , Actividad Motora/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Síndrome de Abstinencia a Sustancias/metabolismo , Síndrome de Abstinencia a Sustancias/fisiopatología , Tirosina 3-Monooxigenasa/administración & dosificación , Tirosina 3-Monooxigenasa/antagonistas & inhibidores , Tirosina 3-Monooxigenasa/farmacocinética
9.
Pharmacotherapy ; 23(7): 823-34, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12885095

RESUMEN

OBJECTIVES: To study the efficacy and safety of 4-aminopyridine (4-AP), and to document sensorimotor changes after discontinuation of the drug in patients with long-term spinal cord injury. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: Clinical research unit. PATIENTS: Twenty-seven patients with long-term spinal cord injury. INTERVENTION: Patients were randomized to receive either oral 4-AP 5 mg/day, which was increased by 5 mg/week to a maximum dosage of 30 mg/day, or placebo for 12 weeks. They switched to the opposite treatment for the next 12 weeks. MEASUREMENTS AND MAIN RESULTS: Twenty-five patients finished the study. The results from the first 12 weeks were used to test efficacy. Positive gains in motor function, sensation, and independence occurred more frequently in patients receiving 4-AP (69%) than those receiving placebo (46%). Significant functional improvement was also noted in those treated with 4-AP (chi2, p=0.042). When each evaluation scale was considered separately, significant improvement was seen only in motor function (4-AP 92% vs placebo 46%, Fisher exact test, p=0.03). Persistent effects of the drug were assessed at week 24 in the group that initially received 4-AP. A persistent, significant 4-AP effect was observed in evaluations of sensation and independence (67% and 83% of patients, respectively; Wilcoxon signed rank test, p=0.032 and 0.042, respectively). Fourteen (56%) patients had 26 adverse reactions. One moderate adverse reaction--posterior tibial artery vasospasm--and 25 mild adverse reactions, such as dry mouth, dizziness, nausea, gastritis, oral and peripheral paresthesia, resolved adequately. Six (24%) patients experienced transitory alterations of enzyme levels (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and creatine kinase) and thrombocytopenia. CONCLUSION: Patients who received 4-AP showed significant improvement in motor function, and a persistent effect on sensation and independent function occurred. The drug is safe; however, after starting 4-AP therapy, patients must be carefully monitored for the possible occurrence of peripheral vasospasm.


Asunto(s)
4-Aminopiridina/efectos adversos , 4-Aminopiridina/uso terapéutico , Bloqueadores de los Canales de Potasio/efectos adversos , Bloqueadores de los Canales de Potasio/uso terapéutico , Traumatismos de la Médula Espinal/tratamiento farmacológico , 4-Aminopiridina/administración & dosificación , Administración Oral , Adulto , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/efectos de los fármacos , Bloqueadores de los Canales de Potasio/administración & dosificación , Umbral Sensorial/efectos de los fármacos , Traumatismos de la Médula Espinal/fisiopatología , Resultado del Tratamiento
10.
Cell Cycle ; 12(15): 2510-7, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23839032

RESUMEN

The function of Cyclin D1 (CycD1) has been widely studied in the cell nucleus as a regulatory subunit of the cyclin-dependent kinases Cdk4/6 involved in the control of proliferation and development in mammals. CycD1 has been also localized in the cytoplasm, where its function nevertheless is poorly characterized. In this work we have observed that in normal skin as well as in primary cultures of human keratinocytes, cytoplasmic localization of CycD1 correlated with the degree of differentiation of the keratinocyte. In these conditions, CycD1 co-localized in cytoplasmic foci with exocyst components (Sec6) and regulators (RalA), and with ß1 integrin, suggesting a role for CycD1 in the regulation of keratinocyte adhesion during differentiation. Consistent with this hypothesis, CycD1 overexpression increased ß1 integrin recycling and drastically reduced the ability of keratinocytes to adhere to the extracellular matrix. We propose that localization of CycD1 in the cytoplasm during skin differentiation could be related to the changes in detachment ability of keratinocytes committed to differentiation.


Asunto(s)
Adhesión Celular , Diferenciación Celular , Ciclina D1/metabolismo , Queratinocitos/metabolismo , Piel/citología , Células Cultivadas , Citoplasma/metabolismo , Matriz Extracelular/metabolismo , Humanos , Integrina beta1/metabolismo , Queratinocitos/fisiología , Transporte de Proteínas , Proteínas de Transporte Vesicular/metabolismo
11.
Talanta ; 74(4): 871-8, 2008 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18371722

RESUMEN

Radial basis neural networks (RBNNs) were developed and evaluated for discrimination of specimens of 'aguardiente de Cocuy', a spirituous beverage produced in the northwestern region of Venezuela. The beverage is distilled from the must of Agave cocui Trelease in an artisanship fashion with little quality control. Forty specimens, with known concentrations of copper, iron, and zinc, were used in this study. The specimens were previously collected in various locations around Sucre Municipality (Falcón State) and Urdaneta Municipality (Lara State). The normalized concentrations of these elements served as indirect descriptors of origin (input data). They were presented to the neural networks through 1-3 input nodes in seven different combinations. In addition, two categories (two collection sites) and four categories (two collection sites+two manufacturing conditions) were designated as output data, in order to assess the impact of such selection on the discrimination performance. The overall performance of the four-category RBNNs was as follows (the input data is indicated in parentheses): (Cu-Fe)>(Cu-Zn)>(Cu)>(Zn)>(Fe-Zn)>(Cu-Fe-Zn)>(Fe). In this case, the highest percentage of correct hits was 82.5%. For the two-category RBNNs, the performance decreased as indicated below: (Cu)>(Cu-Fe)>(Cu-Zn)>(Fe-Zn)>(Zn) approximately (Cu-Fe-Zn)>(Fe). The reduction in the number of categories led to an increase in the discrimination performance of all the RBNNs, the best of which was 90.0%. The possibility of discriminating specimens of 'aguardiente de Cocuy' with such an accuracy, based on a single-element determination, is particularly attractive as it would result in a reduction of analysis' costs and laboratory's response time.


Asunto(s)
Bebidas Alcohólicas/análisis , Redes Neurales de la Computación , Oligoelementos/análisis
12.
Nucleus (La Habana) ; (54): 1-7, jul.-dic. 2013.
Artículo en Español | LILACS | ID: lil-738981

RESUMEN

Para la aplicación exitosa de la técnica del en estudios de erosión del suelo es necesario establecer correctamente el inventario de referencia que representa la entrada total de este radionúclido a la superficie terrestre. En tal sentido, se selecciona un sitio que no haya sido perturbado ni por la erosión ni por el depósito, reconocido como sitio de referencia. En la práctica encontrar estos sitios suele ser difícil. El objetivo de esta investigación fue establecer el inventario de referencia de para localidades de la provincia de Cienfuegos. Quedó establecido que el intervalo de confianza del inventario de referencia de es [1082; 1266] , con una confiabilidad del 90% y el coeficiente de variación del inventario de referencia en las localidades investigadas fue de 11%. Estos valores están en correspondencia con los reportados por otros autores para sitios similares. Asimismo, se determinó la dependencia lineal entre los inventarios de y los promedios históricos de las precipitaciones, con un coeficiente de correlación de 0.94. Esta función lineal se podrá utilizar en la estimación de los inventarios de referencia donde sea complejo encontrar sitios de referencia y por el contrario se disponga de suficiente información respecto a las precipitaciones.


For the successful application of the technique in soil erosion studies, it is necessary to establish the reference inventory correctly as it represents the total entrance of this radionuclide into the earth’s surface. In this sense, a site that has not been perturbed neither for the erosion nor for the deposit, is selected as reference site. In practice to find such sites is usually difficult. The objective of this research was to establish the reference inventory of for the studied localities of Cienfuegos province. It was established that the confidence interval at 90% of probability of the reference inventory is [1082; 1266] , and the variation coefficient of the reference inventory in the researched localities was of 11%. These values are in correspondence with those reported by other authors for similar places. Also the lineal dependence between the inventories of and the historical averages of the precipitations was determined, with a correlation coefficient of 0.94. This lineal function will be able to be used to obtain or to confirm the reference inventories from rainfall data.

14.
Nucleus (La Habana) ; (50): 31-35, jul.-dic. 2011.
Artículo en Español | LILACS | ID: lil-738953

RESUMEN

RESUMEN Las explosiones nucleares de gran potencia a cielo abierto, debido a las pruebas de armas nucleares o como consecuencia de accidentes que han tenido lugar, son las principales causas de que gran número de radionúclidos se haya dispersado en todo el globo terráqueo. Entre estos se encuentra el cesio-137, que al llegar al suelo se adhiere fuertemente a sus partículas más finas. Ello, junto a su período de semidesintegración de 30 años y su fácil detección por gamma espectrometría hacen que se use como radiotrazador de los movimientos del suelo. Esta técnica, ampliamente usada y validada en diferentes entornos en todo el mundo, también fue previamente validada y se demostró su eficacia en la provincia de Cienfuegos. El objetivo de esta investigación fue estudiar mediante el uso del cesio 137, la redistribución del suelo y cuantificar la erosión en áreas protegidas de la provincia, donde las pérdidas de suelo y el arrastre de sedimentos son las principales causas del deterioro de estos ecosistemas con las consiguientes pérdidas económicas y ambientales. Los resultados obtenidos se interpolaron, empleando el método kriging mediante el software gvSIG, obteniendo un mapa de la distribución del suelo en las parcelas estudiadas, y garantizando una mejor visibilidad al respecto. El método se puede aplicar en otros lugares donde sea necesario conocer la magnitud de los problemas de erosión y la redistribución del suelo en el paisaje, lo cual puede ser muy útil para trazar los planes de reordenamiento de los usos del suelo.


ABSTRACT The large-scale nuclear explosions as a result of nuclear weapons tests or nuclear accidents are the main causes of/for the great dispersion of artificial radionuclides all over the world. One of these radionuclides is cesium-137, which is strongly fixed to the fine soils particles. This fact, together with its half-life of 30 years and its easy detection by gamma spectrometry have turned cesium 137, in a good radiotracer of soil movement. This technique has been widely used and validated in different landscapes throughout the world. Its effectiveness was also previously validated and proved in Cienfuegos province as well. This research was aimed at using the cesium-137 technique to study soil redistribution and quantify erosion in the so called Protected Areas in Cienfuegos province, where soil loss and sediment transport are the main causes of deterioration of these ecosystems with the consequent economic and / or environmental losses. The results were represented in a map using the gvSIG software by kriging, thus achieving greater visibility of the soil redistribution in the studied plot. The methodology used in this study could be used in other places wherever the magnitude of erosion problemsas well as knowing the soil redistribution plot pattern in the landscape are necessary and very useful to elaborate plans for rearrangement in land use management.

15.
Anal Bioanal Chem ; 381(3): 788-94, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15688156

RESUMEN

A generalized regression artificial neural network (GRANN) was developed and evaluated for modeling cadmium's nonlinear calibration curve in order to extend its upper concentration limit from 4.0 microg L-1 up to 22.0 microg L-1. This type of neural network presents important advantages over the more popular backpropagation counterpart which are worth exploiting in analytical applications, namely, (1) a smaller number of variables have to be optimized, with the subsequent reduction in "development hassle"; and, (2) shorter development times, thanks to the fact that the adjustment of the weights (the artificial synapses) is a non-iterative, one-pass process. A backpropagation artificial neural network (BPANN), a second-order polynomial, and some less frequently employed polynomial and exponential functions (e.g., Gaussian, Lorentzian, and Boltzmann), were also evaluated for comparison purposes. The quality of the fit of the various models, assessed by calculating the root mean square of the percentage deviations, was as follows: GRANN>Boltzmann>second-order polynomial>BPANN>Gauss>Lorentz. The accuracy and precision of the models were further estimated through the determination of cadmium in the certified reference material "Trace Metals in Drinking Water" (High Purity Standards, Lot No. 490915), which has a cadmium certified concentration (12.00+/-0.06 microg L-1) that lies in the nonlinear regime of the calibration curve. Only the models generated by the GRANN and BPANN accurately predicted the concentrations of a series of solutions, prepared by serial dilution of the CRM, with cadmium concentrations below and above the maximum linear calibration limit (4.0 microg L-1). Extension of the working range by using the proposed methodology represents an attractive alternative from the analytical point of view, since it results in less specimen manipulation and consequently reduced contamination risks without compromising either the accuracy or the precision of the analyses. The implementation of artificial neural networks also helps to reduce the trial-and-error task of looking for the right mathematical model from among the many possibilities currently available in the various scientific and statistic software packages.

16.
Rev. cuba. med ; 48(3): 28-35, jul.-sep. 2009.
Artículo en Español | LILACS | ID: lil-628867

RESUMEN

La población de hemodiálisis constituye un grupo de alto riesgo en el caso de la infección por el virus de la hepatitis C. Se realizó un análisis multicéntrico de la prevalencia de la infección por el virus de la hepatitis C en las unidades de diálisis de la región occidental aplicando las técnicas serológicas y moleculares, y se observó si existían diferencias significativas en cuanto a la aplicación de ambas técnicas. Se obtuvieron valores elevados de prevalencia de anticuerpos anti-VHC en todas las unidades de diálisis (76 %), así como la calculada aplicando la detección del ARN viral (55 %). No se hallaron diferencias significativas (k) en cuanto a la aplicación de ambas técnicas en la mayoría de las unidades de diálisis analizadas. La elevada prevalencia viral se asocia a la transmisión nosocomial provocada por el incumplimiento de las normas de precaución universal establecidas.


Hemodialysis population is a high risk group related to hepatitis C virus infection. Authors made a multicenter analysis on infection prevalence of hepatitis C virus in dialysis units of western region applying serologic and molecular techniques observing if there significant differences as regards the application of both techniques. We achieved high values of anti-CHV antibody prevalence in all dialysis units (76 %) as well as the estimated prevalence applying viral RNA detection (55 %). There were not significant differences (k) as regards application of both techniques in most of analyzed dialysis units. Viral high prevalence is associated with nosocomial transmission caused by no-fulfillment of established universal precaution standards.

17.
Nucleus (La Habana) ; (44): 8-14, jul.-dic. 2008.
Artículo en Español | LILACS | ID: lil-738911

RESUMEN

RESUMEN El principal objetivo de esta investigación fue desarrollar y validar un método de separación radioquímica del plutonio, factible desde el punto de vista económico y práctico en las condiciones de Cuba que nos permitiera determinar los niveles de plutonio en los sedimentos marinos de la bahía de Cienfuegos. El método de separación radioquímica seleccionado fue el de cromatografía aniónica y la técnica de medición, la espectrometría de masa con cuadrupolo y plasma inducido asociado. El método se aplicó a una muestra de referencia certificada, realizándose seis repeticiones y obteniéndose una buena correspondencia entre el valor medio medido de plutonio y su valor medio certificado. Se comprobó la buena reproducibilidad del método, ya que se obtuvo un coeficiente de variación de 11% para 95% de probabilidad. Los resultados de la aplicación del método validado, revelan que la presencia de plutonio en las muestras analizadas se debe únicamente a las precipitaciones radiactivas globales.


ABSTRACT The main objective of this research was to develop and to validate a method of radiochemical separation of plutonium, suitable from the economic and practical point of view, in Cuba conditions. This method allowed us to determine plutonium activity levels in the marine sediments from Cienfuegos Bay. The selected method of radiochemical separation was that of anionic chromatography and the measure technique was the quadrupole inductively coupled plasma mass spectrometry. The method was applied to a certified reference material, six repetitions were carried out and a good correspondence between the average measured value and the average certified value of plutonium was achieved, so the trueness of the method was demonstrated. It was also proven the precision of the method, since it was obtained a variation coefficient of 11% at 95% confidence level. The obtained results show that the presence of plutonium in the analyzed marine sediment samples is only due to the global radioactive fallout.

18.
Rev. cuba. med. mil ; 26(2): 110-5, jul.-dic. 1997. tab
Artículo en Español | LILACS | ID: lil-223104

RESUMEN

Se realizó un estudio clínico fase II con 60 pacientes para conocer la eficacia del tratamiento con láser helio-neón en las pérdidas óseas horizontales. Los pacientes se dividieron en 2 grupos de 30: un grupo de estudio, en el que se realizó colgajo Kirkland e irradiación con láser helio-neón en una sola dosis de 3 J/cm² en el acto quirúrgico, y un grupo control al que solamente se le realizó colgajo Kirkland. En las mediciones se utilizaron pie de rey y radiografías periapicales. Se utilizó el equipo Lasermed 101 M de fabricación cubana con potencia de salida de 2MW y fibra óptica. Se aplicó el índice de Love para medir la eficiencia del cepillado. El 100 por ciento de los pacientes con periodontitis simple incipiente tuvieron ganancia ósea parcial, mientras que de los que presentaban periodontitis simple moderada, el 83 por ciento mostró ganancia ósea total en el 10 por ciento del grupo tratado; sin embargo, el grupo control se mantuvo sin cambios en el 100 por ciento. En el índice de Love los pacientes que se mantuvieron estables del grupo que había recibido tratamiento con láser presentaron valores superiores al 20 por ciento. Se concluyó que el tratamiento con láser helio-neón en el acto quirúrgico resultó eficaz


Asunto(s)
Humanos , Masculino , Femenino , Regeneración Tisular Dirigida , Periodontitis/radioterapia , Periodontitis/cirugía , Rayos Láser/uso terapéutico , Higiene Bucal
19.
Acta méd. domin ; 17(6): 218-21, nov.-dic. 1995. ilus
Artículo en Español | LILACS | ID: lil-269087

RESUMEN

Antecedentes: Jesús, en el huerto de Getsemaní, poco antes de entrar en su pasión, según relatan los evangelistas "su sudor se convirtió en gruesas gotas de sangre que caían hasta el suelo. Además de este caso, solamente dos casos mas hemos encontrado reportados en la literatura médica mundial. Materiales: Paciente femenina de 22 años de edad, raza blanca, natural y residente en el paraje Soledad, Moca, Prov. Espaillat, R.D. y su hijo varón de tres años de edad, en quienes se reportan sudoración de sangre en mas de una oportunidad, Conclusión: se trata sin lugar a dudas de casos de hematohidrosis, algo excepcional reportado, posiblemente por primera vez en la República Dominicana


Asunto(s)
Humanos , Femenino , Adulto , Preescolar , Glándulas Sudoríparas/anomalías , Sudor/metabolismo
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