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1.
J Sport Exerc Psychol ; 37(5): 559-64, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26524101

RESUMEN

The abrupt onset of a visual stimulus typically results in overt attentional capture, which can be quantified by saccadic eye movements. Here, we tested whether attentional capture following onset of task-irrelevant visual stimuli (new object) is reduced after a bout of intense physical exercise. A group of participants performed a visual search task in two different activity conditions: rest, without any prior effort, and effort, immediately after an acute bout of intense exercise. The results showed that participants exhibited (1) slower reaction time of the first saccade toward the target when a new object was simultaneously presented in the visual field, but only in the rest activity condition, and (2) more saccades to the new object in the rest activity condition than in the effort activity condition. We suggest that immediately after an acute bout of effort, participants improved their ability to inhibit irrelevant (distracting) stimuli.


Asunto(s)
Atención/fisiología , Ejercicio Físico/fisiología , Movimientos Oculares/fisiología , Reconocimiento Visual de Modelos/fisiología , Desempeño Psicomotor/fisiología , Adulto , Femenino , Humanos , Masculino , Adulto Joven
2.
Psychol Res ; 78(2): 248-65, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23605318

RESUMEN

Recent evidence led to the conclusion that addition problems are biased towards overestimation, regardless of whether information is conveyed by symbolic or non-symbolic stimuli (the Operational Momentum effect). The present study focuses on the role of operands in the overestimation of addition problems. Based on the tie effect, and on recent evidence that the nature of operands biases addition problems towards an underestimation when operands are repeated, but towards an overestimation when different, we aim here to further elucidate the contribution of operands to addition problems. Experiment 1 replicates the underestimation of repeated-operand additions and overestimation of different-operand additions, with large numbers (around 50), and explores whether these effects also apply to small operand additions (around 10). Experiment 2 further explores the overestimation of different-operand additions by investigating the roles of operand order and numerical distance between operands. The results show that both factors have an impact on the overestimation size, but are not crucial for overestimation to occur. The results are discussed in terms of arithmetic strategies, spatial organization of numbers and magnitude representation.


Asunto(s)
Cognición , Solución de Problemas , Adolescente , Adulto , Femenino , Humanos , Masculino , Matemática , Tiempo de Reacción , Adulto Joven
3.
Acta Gastroenterol Latinoam ; 43(2): 146-8, 2013 Jun.
Artículo en Español | MEDLINE | ID: mdl-23940918

RESUMEN

Biliary obstructions are infrequently caused by foreign bodies. We present an unusual case of angiographically placed metallic coils into the intrahepatic arteries to provide hemostasis, that subsequently eroded into the common bile duct leading to obstructive jaundice and cholangitis a year later. In patients with history of invasive procedures, the possibility of foreign body migration into the common bile duct should always be considered in the differential diagnosis of obstructive jaundice and cholangitis.


Asunto(s)
Colangitis/etiología , Colestasis/etiología , Migración de Cuerpo Extraño/complicaciones , Enfermedad Aguda , Embolización Terapéutica/efectos adversos , Embolización Terapéutica/instrumentación , Arteria Hepática , Humanos , Masculino , Persona de Mediana Edad
4.
Antioxidants (Basel) ; 11(10)2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36290638

RESUMEN

Oxidative stress is an important component of many diseases including cancer, along with inflammatory and neurodegenerative processes. Natural antioxidants have emerged as promising substances to protect the human body against reactive oxygen and nitrogen species. The present study evaluates the inhibition of nitric oxide (NO) production in LPS-stimulated RAW 264.7 murine macrophages and the free radical scavenging activity of Croton linearis Jacq. leaves. UPLC-QTOF-MS analysis identified 18 compounds: nine alkaloids with a morphinane, benzylisoquinoline or aporphine nucleus, and nine O-glycosylated-flavonoids with quercetin, kaempferol and isorhamnetin as the aglycones. The crude extract (IC50 21.59 µg/mL) and the n-hexane fraction (IC50 4.88 µg/mL) significantly reduced the NO production in LPS-stimulated macrophages but with relatively high cytotoxicity (CC50 75.30 and CC50 70.12 µg/mL, respectively), while the ethyl acetate fraction also showed good activity (IC50 40.03 µg/mL) without affecting the RAW 264.7 cell viability. On the other hand, the crude extract, as well as the dichloromethane and ethyl acetate fractions, showed better DPPH and ABTS free radical scavenging activities. Considering the chemical composition and the activity observed for Croton linearis leaves, they may be considered a good source of antioxidants to combat oxidative damage-related diseases.

5.
Am Surg ; 76(11): 1244-50, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21140693

RESUMEN

The aim of this study is to analyze the clinical outcome of gastrointestinal stromal tumors (GISTs) and to determine new prognostic factors. We perform a retrospective study of all the patients diagnosed with GIST in any location and operated on between 2000 and 2008 at our institution. We analyzed 35 patients, 16 males (45.7%) and 19 females (54.3%), with a mean age of 64 +/- 13.8 years. The tumors were located in the stomach in 22 patients (62.9%), in the small bowel in 10 (28.6%), and the retroperitoneum in three (8.6%). Referring to gastric GIST, endoscopy revealed an ulceration in the mucosa in five cases, suggesting an epithelial neoplasm. In all these cases, pathology of the biopsy specimen was nonconclusive. Survival rate at 1 and 5 years was 94.3 and 88.6 per cent, respectively. Disease-free survival at 1 and 2 years was 91.4 and 88.6 per cent, respectively. Analyzing prognostic factors, a lower disease-free survival was observed among patients with constitutional syndrome at diagnosis (P = 0.000), small bowel GIST (P = 0.037), and tumors not expressing actin (P = 0.015). A lower global survival was observed among men (P = 0,036), patients with an abdominal mass (P = 0.033) or with constitutional syndrome (P = 0.007) at diagnosis and tumors at a retroperitoneal location (P = 0.0002). Gastric GIST may be confused with epithelial neoplasms, modifying the surgery. In our patients, masculine gender, constitutional syndrome and abdominal mass at diagnosis, small bowel and retroperitoneal location, and actin negative tumors are bad prognostic factors.


Asunto(s)
Actinas/metabolismo , Tumores del Estroma Gastrointestinal/metabolismo , Tumores del Estroma Gastrointestinal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Biopsia con Aguja Fina , Endoscopía Gastrointestinal , Endosonografía , Femenino , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/patología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
6.
Am Surg ; 76(12): 1408-11, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21265357

RESUMEN

Laparoscopic surgery has become the elective approach for the surgical treatment of gastroesophageal reflux disease in the last decade. Outcome data beyond 10 years are available for open fundoplication, with good-to-excellent results, but few studies report long-term follow-up after laparoscopic fundoplication. We performed a retrospective study of all the patients that underwent laparoscopic Nissen and Toupet fundoplications as antireflux surgery between 1995 and 1998 in our institution. To evaluate the long-term results, a face-to-face interview was performed in 2009. One hundred and six patients were included in the study. Surgical techniques performed were Nissen fundoplication (NF) in 56 patients and Toupet (TF) in 50. Complication rate was 4 per cent in both groups (nonsignificant [NS]). Two patients (4%) of NF required reoperation because of dysphagia. After 10 years, 10 per cent of the patients remain symptomatic in both groups. Fifteen per cent of NF take daily inhibitors of the proton pump versus 14 per cent of TF (NS). Twenty per cent of NF refer dysphagia, all of them without evidence of stenosis at endoscopy or contrasted studies. The satisfaction rate of the patients was 96 per cent in NF and 98 per cent in TF. Laparoscopic Toupet fundoplication seems to be as safe and long-term effective as Nissen, but with a lower incidence of postoperative dysphagia. In our experience Toupet fundoplication should be the elective approach for the surgical treatment of gastroesophageal reflux disease.


Asunto(s)
Fundoplicación/métodos , Reflujo Gastroesofágico/cirugía , Adulto , Anciano , Femenino , Humanos , Laparoscopía , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Cir Esp ; 88(2): 92-6, 2010 Aug.
Artículo en Español | MEDLINE | ID: mdl-20561608

RESUMEN

INTRODUCTION: Acute cholecystitis treatment may initially be surgical or conservative with subsequent surgery; we reviewed the cases found in our centre, including their treatment and outcome. MATERIAL AND METHODS: We conducted a retrospective study of treatment in 178 patients with acute cholecystitis during one year. We evaluated variables associated with patient characteristics, as well as clinical data, diagnostic tests, treatment and outcome. RESULTS: The majority (70.2%) was treated conservatively (group A), and 29.8% were operated on in the first 72 h (group B). In group A, 96 patients were treated with antibiotics, 15 with antibiotic therapy and cholecystectomy, and 12 with antibiotics and ERCP. In group B urgent laparoscopic cholecystectomy was performed in 60.4%, and 35.8% had open cholecystectomy. In group A, admission time was 11 days, with satisfactory progress in 79.2%, mortality rate of 5.6% and 10.7% of readmissions. In group B, operation time was 111 +/- 43 min, a mean of 8.7 days hospital stay, and 68% of cases did not require further treatment after surgery. Outcome was satisfactory in all but 7, there was no mortality in this group. We had a return rate of 2%. CONCLUSIONS: A significant proportion of conservative treatment was carried out at the expense of emergency surgery, although in absolute numbers conservative treatment seems to have a higher rate of complications, mortality and hospitalisation time.


Asunto(s)
Colecistitis/cirugía , Enfermedad Aguda , Anciano , Colecistectomía/métodos , Colecistectomía/normas , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
9.
Int J Med Sci ; 6(6): 301-4, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19774200

RESUMEN

Klebsiella pneumoniae isolated in community-acquired pneumonia is increasingly found in primary pyogenic liver abscesses. The presence of magA in K. pneumoniae has been implicated in hypermucoviscosity and virulence of liver abscess isolates. The K2 serotype has also been strongly associated with hypervirulence. We report the isolation of non-magA, K2 K. pneumoniae strain from a liver abscess of a Saint Kitt's man who survived the invasive syndrome.


Asunto(s)
Absceso Encefálico/microbiología , Klebsiella pneumoniae/aislamiento & purificación , Absceso Hepático/microbiología , Secuencia de Bases , Absceso Encefálico/diagnóstico por imagen , Cartilla de ADN , Humanos , Klebsiella pneumoniae/genética , Absceso Hepático/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , San Kitts y Nevis , Tomografía Computarizada por Rayos X
10.
Am Surg ; 75(12): 1179-82, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19999908

RESUMEN

The volvulus of the small bowel is a surgical emergency, causing small bowel obstruction. We performed a retrospective study of all the patients diagnosed and treated with small bowel volvulus between 1977 and 2007 at our institution. One hundred twenty-nine patients were analyzed. Thirty-nine patients presented primary volvulus and 90 secondary ones. The most frequent symptom was sudden abdominal pain. CT scan was the best diagnostic method with an accuracy of 83 per cent. Necrotic small bowel loops appeared in 46.5 per cent of the patients. Eighteen patients had postoperative complications (14%). Mortality rate was 9.3 per cent. A higher mortality is observed among patients with previous abdominal surgeries and cardiopathies. Necrotic loops are associated with higher mortality and incidence of surgical complications; patients with diabetes are associated with a higher incidence of necrotic loops. Cardiopathies are associated with more frequent medical and surgical complications. Recurrence rate was 3.9 per cent associated with simple devolvulation. Primary volvulus are more frequent among males and patients with diabetes. Jejunal location is associated with primary volvulus and these correlate with a higher incidence of necrotic loops. Primary volvulus presents a higher incidence of surgical complications. A bowel obstruction with sudden abdominal pain must be suspicious of small bowel volvulus. The main aim is to achieve an early diagnosis to prevent a necrotic small bowel. CT scan is the imaging test with the best diagnostic accuracy. Primary volvulus, the presence of necrotic loops, and patients with cardiopathies, diabetes mellitus, and with previous abdominal surgery are associated with a worse outcome.


Asunto(s)
Vólvulo Intestinal/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neuropatías Diabéticas/complicaciones , Femenino , Humanos , Vólvulo Intestinal/diagnóstico , Vólvulo Intestinal/etiología , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Necrosis , Estudios Retrospectivos , Adulto Joven
11.
Accid Anal Prev ; 126: 198-208, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-29061281

RESUMEN

Attention lapses and fatigue are a main source of impaired performance that can lead to accidents. This study analyzed electroencephalographic (EEG) dynamics and body skin temperature as markers of attentional fluctuations in non-sleep deprived subjects during a 45min Psychomotor Vigilance Task (PVT). Independent Component Analysis and time-frequency analysis were used to evaluate the EEG data. Results showed a positive association between distal and distal-to-proximal gradient (DPG) temperatures and reaction time (RT); increments in EEG power in alpha-, theta- and beta-band frequencies in parieto-occipital, central-medial and frontal components, were associated with poor performance (slower RT) in the task. This generalized power increment fits with an increased activity in the default mode network, associated with attention lapses. This study highlights the potential use of the PVT as a tool to obtain individual physiological indices of vigilance and fatigue that could be applied to other vigilance tasks typically performed in occupational settings.


Asunto(s)
Atención/fisiología , Desempeño Psicomotor/fisiología , Temperatura , Vigilia/fisiología , Adulto , Electroencefalografía , Fatiga/complicaciones , Femenino , Humanos , Tiempo de Reacción/fisiología , Adulto Joven
12.
Foods ; 8(11)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739559

RESUMEN

Increasing interest in constituents and dietary supplements has created the need for more efficient use of this information in nutrition-related fields. The present work aims to obtain optimal models to predict the total antioxidant properties of food matrices, using available information on the amount and class of flavonoids present in vegetables. A new dataset using databases that collect the flavonoid content of selected foods has been created. Structural information was obtained using a structural-topological approach called TOPological Sub-Structural Molecular (TOPSMODE). Different artificial intelligence algorithms were applied, including Machine Learning (ML) methods. The study allowed us to demonstrate the effectiveness of the models using structural-topological characteristics of dietary flavonoids. The proposed models can be considered, without overfitting, effective in predicting new values of Oxygen Radical Absorption capacity (ORAC), except in the Multi-Layer Perceptron (MLP) algorithm. The best optimal model was obtained by the Random Forest (RF) algorithm. The in silico methodology we developed allows us to confirm the effectiveness of the obtained models, by introducing the new structural-topological attributes, as well as selecting those that most influence the class variable.

13.
Am Surg ; 74(1): 27-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18274424

RESUMEN

Most duodenal diverticula are asymptomatic, incidentally discovered at endoscopy or barium studies. Upper gastrointestinal bleeding has been described, but it is an infrequent complication. We describe the 14th case reported in the literature of massive upper gastrointestinal bleeding originating from a duodenal diverticulum.


Asunto(s)
Divertículo/complicaciones , Divertículo/diagnóstico , Enfermedades Duodenales/complicaciones , Enfermedades Duodenales/diagnóstico , Hemorragia Gastrointestinal/etiología , Divertículo/cirugía , Enfermedades Duodenales/cirugía , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/cirugía , Humanos , Masculino , Persona de Mediana Edad
14.
J Sport Health Sci ; 7(4): 497-504, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30450260

RESUMEN

PURPOSE: The present study aimed to investigate the relationship between different types of sport expertise (externally-paced vs. self-paced sports) and vigilance performance in children by evaluating the cardiovascular fitness level of the participants. METHODS: Three groups of children (11.0 ± 0.2 years) differentiated in terms of their regular sport participation (football players, n = 20; track and field athletes, n = 20; non-athletic controls, n = 20) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In another session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance under 2 conditions of velocity demands (normal vs. speed). RESULTS: The results revealed that both groups of sport practitioners had higher cardiovascular fitness than non-athlete controls. In contrast, no significant differences in the performance PVT were found between track and field athletes and controls. Crucially, football players showed better performance in the PVT than track and field athletes and controls. These between-group differences were not modulated by the speed demands of the task. CONCLUSION: The major novel finding of this research points to a positive relationship between sport participation and vigilance performance during childhood. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between regular exercise and cognitive functioning: the "cardiovascular fitness" and the "cognitive component skills" hypotheses.

15.
Front Psychol ; 9: 688, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29867659

RESUMEN

Attention maintenance is highly demanding and typically leads to vigilance decrement along time on task. Therefore, performance in tasks involving vigilance maintenance for long periods, such as driving, tends to deteriorate over time. Cognitive performance has been demonstrated to fluctuate over 24 h of the day (known as circadian oscillations), thus showing peaks and troughs depending on the time of day (leading to optimal and suboptimal times of day, respectively). Consequently, vigilance decrements are more pronounced along time on task when it is performed at suboptimal times of day. According to research, light exposure (especially blue-enriched white) enhances alertness. Thus, it has been proposed to prevent the vigilance decrement under such adverse circumstances. We aimed to explore the effects of blue-enriched white light (vs. dim light) on the performance of a simulated driving task at a suboptimal time of day. A group of evening-types was tested at 8 am, as this chronotype had previously shown their largest vigilance decrement at that time. In the dim light condition, vigilance decrements were expected on both subjective (as increments in the Karolinska Sleepiness Scale scores) and behavioral measures [as slower reaction times (RTs) in the auditory Psychomotor Vigilance Task, slower RTs to unexpected events during driving, and deteriorated driving accuracy along time on task]. Physiological activation was expected to decrease (as indexed by an increase of the distal-proximal temperature gradient, DPG). Under blue-enriched white light, all these trends should be attenuated. Results from the control dim light condition replicated the vigilance decrement in all measures. Most important, the blue-enriched white light attenuated this decrement, leading to both lower DPG and faster RTs. However, it impaired accuracy of driving performance, and did not have any effect on subjective sleepiness. We conclude that exposure to blue-enriched light provides an effective countermeasure to enhance vigilance performance at suboptimal times of day, according to measures such as RTs. However, it should be considered that alerting effects of light could impair accuracy in precision tasks as keeping a proper car position. The current findings provide ergonomic implications for safety and fatigue related management systems.

16.
Front Psychol ; 8: 997, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28690558

RESUMEN

Vigilance usually deteriorates over prolonged driving at non-optimal times of day. Exposure to blue-enriched light has shown to enhance arousal, leading to behavioral benefits in some cognitive tasks. However, the cognitive effects of long-wavelength light have been less studied and its effects on driving performance remained to be addressed. We tested the effects of a blue-enriched white light (BWL) and a long-wavelength orange light (OL) vs. a control condition of dim light on subjective, physiological and behavioral measures at 21:45 h. Neurobehavioral tests included the Karolinska Sleepiness Scale and subjective mood scale, recording of distal-proximal temperature gradient (DPG, as index of physiological arousal), accuracy in simulated driving and reaction time in the auditory psychomotor vigilance task. The results showed that BWL decreased the DPG (reflecting enhanced arousal), while it did not improve reaction time or driving performance. Instead, blue light produced larger driving errors than OL, while performance in OL was stable along time on task. These data suggest that physiological arousal induced by light does not necessarily imply cognitive improvement. Indeed, excessive arousal might deteriorate accuracy in complex tasks requiring precision, such as driving.

17.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1537056

RESUMEN

Los ovinos criollos de pelo (OCP) desarrollaron ventajas adaptativas al climática tropical, que le permiten tener resistencia a enfermedades, alta fertilidad y prolificidad; sin embargo, se reportan pocas investigaciones sobre la productividad de los OCP en sistemas asociados al cultivo de la caña, lo que hace necesario realizar investigaciones, que permitan fomentar sus atributos. El objetivo del presente trabajo fue analizar la productividad y el desarrollo corporal de un cruce de OCP, mediante parámetros productivos y curvas de crecimiento. Se utilizaron 180 animales de partos simples y múltiples; se registró el peso al nacimiento (PN), al destete (PD), a los 210 días (PAJ210) y las ganancias diarias predestete (GDPRE) y posdestete (GDPOS). Los datos, se analizaron mediante estadística descriptiva, con un GLM, con los efectos sexo (S), tipo de nacimiento (TN), número de partos (NP) y época de nacimiento (EPONAC). Se emplearon los modelos no lineales Gompertz, Logístico, Brody, Richards y Von Bertalanffy, en 1.455 registros de pesos, a diferentes edades, para realizar las curvas de crecimiento. Los análisis, se efectuaron con el paquete estadístico SAS. Se consideraron los coeficientes R2, AIC y BIC, obtenidos por el método de Gauss-Newton, para seleccionar el modelo de mejor ajuste. Los machos presentaron mayores promedios en las variables PN, PD, PAJ210 y GDPOS. El TN afectó todas las variables; el PN y las GDPOS fueron afectadas por el NP y, la EPONAC, afectó PN, las GDPRE, el PAJ210 y las GDPOS. El modelo de mejor ajuste para las curvas de crecimiento fue la de Richards.


The creole hair sheep (CHS) developed adaptive advantages to the tropical climate, which allow them to have resistance to diseases, high fertility and prolificacy. Currently, there is little research on the productivity of CHS in systems associated with the cultivation of sugarcane, which makes it necessary to carry out research to promote its attributes. The purpose of this research was to analyze the productivity and body development of a crossing of CHS, using production parameters and growth curves.180 animals of single and multiple births were used; the follow weight was recorded: at birth (WB), at weaning (WW); at 210 days (W210), and furthermore, daily gains of pre-weaning (WDPRE) and post-weaning (WPPOS) were recorded. The data were analyzed using descriptive statistics with a GLM with the effects sex (S), type of birth (TB), number of births (NB) and period of birth (PB). The non-linear models Gompertz, Logistic, Brody, Richards and Von Bertalanffy were used in 1455 records of weights at different ages to perform growth curves. All analyzes were performed with the SAS statistical package. The R2, AIC and BIC coefficients obtained by the Gauss-Newton method were considered to select the best fit model. The males presented higher averages in the variables WB, WW, W210) and WPOS. The TB affected all the variables; The WB and the WPPOS were affected by the NB and the PB affected the WB, the WDPRE, the W210 and the WPPOS. The best fit model for the growth curves was of Richards.

18.
Sci Rep ; 7(1): 516, 2017 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-28364128

RESUMEN

Biogenesis and function of microRNAs can be influenced by genetic variants in the pri-miRNA sequences leading to phenotypic variability. This study aims to identify single nucleotide polymorphisms (SNPs) affecting the expression levels of bone-related mature microRNAs and thus, triggering an osteoporotic phenotype. An association analysis of SNPs located in pri-miRNA sequences with bone mineral density (BMD) was performed in the OSTEOMED2 cohort (n = 2183). Functional studies were performed for assessing the role of BMD-associated miRNAs in bone cells. Two SNPs, rs6430498 in the miR-3679 and rs12512664 in the miR-4274, were significantly associated with femoral neck BMD. Further, we measured these BMD-associated microRNAs in trabecular bone from osteoporotic hip fractures comparing to non-osteoporotic bone by qPCR. Both microRNAs were found overexpressed in fractured bone. Increased matrix mineralization was observed after miR-3679-3p inhibition in human osteoblastic cells. Finally, genotypes of rs6430498 and rs12512664 were correlated with expression levels of miR-3679 and miR-4274, respectively, in osteoblasts. In both cases, the allele that generated higher microRNA expression levels was associated with lower BMD values. In conclusion, two osteoblast-expressed microRNAs, miR-3679 and miR-4274, were associated with BMD; their overexpression could contribute to the osteoporotic phenotype. These findings open new areas for the study of bone disorders.


Asunto(s)
Huesos/metabolismo , MicroARNs/genética , Osteoporosis/genética , Polimorfismo de Nucleótido Simple , Anciano , Alelos , Densidad Ósea , Calcificación Fisiológica , Células Cultivadas , Estudios de Cohortes , Biología Computacional/métodos , Expresión Génica , Frecuencia de los Genes , Genotipo , Humanos , MicroARNs/química , Persona de Mediana Edad , Conformación de Ácido Nucleico , Osteoblastos/metabolismo , Osteoporosis/metabolismo , Osteoporosis/patología , Transcriptoma
19.
J Mol Graph Model ; 25(3): 275-88, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16487735

RESUMEN

We use the topological sub-structural molecular design (TOPS-MODE) approach to formulate structural alert rules for chromosome aberration (CA) of organic compounds. First, a classification model was developed to group chemicals as active/inactive respect to CA. A procedure for extracting structural information from orthogonalized TOPS-MODE descriptors was then implemented. The contributions of bonds to CA in all the molecules studied were then generated using the orthogonalized classification model. Using this information we propose 22 structural alert rules which are ready to be implemented in expert systems for the automatic prediction of CA. They include, among others, structural alerts for N-nitroso compounds (ureas, urethanes, guanidines, triazines), nitro compounds (aromatic and heteroaromatic), alkyl esters or phosphoric acids, alkyl methanesulfonates, sulphonic acids and sulphonamides, epoxides, aromatic amines, azaphenanthrene hydrocarbons, etc. The chemico-biological analysis of some of the structural alerts found is also carried out showing the potential of TOPS-MODE as a knowledge generator.


Asunto(s)
Automatización , Aberraciones Cromosómicas , Compuestos Orgánicos/química , Relación Estructura-Actividad Cuantitativa , Simulación por Computador , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad
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