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1.
Artículo en Inglés | MEDLINE | ID: mdl-39359132

RESUMEN

AIM: To compare the effectiveness of 50 and 100 µg of carbetocin with 10 IU of oxytocin for the prevention of postpartum hemorrhage (PPH). METHODS: This was a triple-blind, non-inferiority trial involving pregnant women recruited at term. We compared two doses of carbetocin (50 and 100 µg) with 10 IU of oxytocin administered as uterotonic agent after vaginal or cesarean delivery. Uterine contractility was assessed at 2- and 5-min after uterotonic administration. The association between adequate uterine tone and PPH with the patients' characteristics were examined using the chi-square test. Effect of the drugs on the odds of developing PPH was examined using logistics regressions. All analyses were conducted using STATA (StataCorp L.L.C.) with a significance level set at 0.05. RESULTS: In total, 324 women (50 µg carbetocin group-111, 100 µg carbetocin group-106, and oxytocin group-107) participated in the study. There was a significantly higher proportion of women with adequate uterine tone in those that had 100 µg carbetocin relative to 50 µg and 10 IU oxytocin at 5 min (p < 0.001). Patients who received oxytocin had a higher average blood loss than women that had either 50 or 100 µg carbetocin (p = 0.128). There was a significant difference in the need for additional uterotonic, with a higher proportion of participants among those who received 10 IU of oxytocin (p < 0.001). CONCLUSION: Patients that had 100 µg of carbetocin had a better adequate uterine tone at the fifth minute compared to those who had 50 µg and 10 IU of oxytocin. Generally, carbetocin use was less likely associated with risk of PPH and use of additional intervention.

2.
Proc Natl Acad Sci U S A ; 117(31): 18477-18488, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32669436

RESUMEN

With the recent explosion in the size of libraries available for screening, virtual screening is positioned to assume a more prominent role in early drug discovery's search for active chemical matter. In typical virtual screens, however, only about 12% of the top-scoring compounds actually show activity when tested in biochemical assays. We argue that most scoring functions used for this task have been developed with insufficient thoughtfulness into the datasets on which they are trained and tested, leading to overly simplistic models and/or overtraining. These problems are compounded in the literature because studies reporting new scoring methods have not validated their models prospectively within the same study. Here, we report a strategy for building a training dataset (D-COID) that aims to generate highly compelling decoy complexes that are individually matched to available active complexes. Using this dataset, we train a general-purpose classifier for virtual screening (vScreenML) that is built on the XGBoost framework. In retrospective benchmarks, our classifier shows outstanding performance relative to other scoring functions. In a prospective context, nearly all candidate inhibitors from a screen against acetylcholinesterase show detectable activity; beyond this, 10 of 23 compounds have IC50 better than 50 µM. Without any medicinal chemistry optimization, the most potent hit has IC50 280 nM, corresponding to Ki of 173 nM. These results support using the D-COID strategy for training classifiers in other computational biology tasks, and for vScreenML in virtual screening campaigns against other protein targets. Both D-COID and vScreenML are freely distributed to facilitate such efforts.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Aprendizaje Automático , Bibliotecas de Moléculas Pequeñas/farmacología , Bases de Datos de Proteínas , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos/instrumentación , Humanos
3.
Appetite ; 169: 105807, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34798222

RESUMEN

Median nerve stimulation (MNS) in the existing literature has been used for treating gastrointestinal disorders and amelioration of nausea and vomiting. Recently, studies have shown that MNS can also exert effects on olfactory performances and corresponding anatomical regions through the activation of vagal pathways. This study aimed to test effects of specific frequencies of MNS on food-related attention and appetite. The experiment used an odourised, dot probe task for testing food-related attention and a combination of behavioural (i.e., visual analogue scales; VAS) and physiological approaches (i.e., electrocardiograph; ECG - root mean square of successive differences between normal heartbeats-RMSSD: parasympathetic nervous system activation (RMSSD), stress index-SI: sympathetic nervous system activation) for measuring hunger, appetite, and satiation. Twenty-four healthy, male adults completed a VAS and dot probe task before and after receiving either 40 Hz-, 80 Hz-, 120 Hz MNS or sham (control) across four different sessions with continuous ECG recording throughout each session. Data from the dot probe task were analysed using repeated-measures ANOVA, while pair-wise tests were used for ECG recordings and VAS. Improvements on the dot probe task, not specific to odour-food congruence were found after 40 Hz MNS (p-value = 0.048; strong effect size (0.308 partial eta squared)) while increased ratings of hunger (VAS) (p-value = 0.03, small effect size (0.47 Cohen-D)) and RMSSD scores (p-value < 0.001; medium effect size (0.76 Cohen-D)) were found after 120 Hz MNS. These findings implore further testing of MNS frequency parameters on improving RMSSD, a characteristic marker of measuring parasympathetic/autonomic nervous system activation pertaining to the vagal network. Furthermore, improving sympathovagal balance is associated with cardiovascular benefits in numerous health-related conditions such as obesity, hypertension and diabetes.


Asunto(s)
Apetito , Nervio Mediano , Adulto , Apetito/fisiología , Atención , Sistema Nervioso Autónomo/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino
4.
Sensors (Basel) ; 22(12)2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35746395

RESUMEN

Parkinson's disease affects millions worldwide with a large rise in expected burden over the coming decades. More easily accessible tools and techniques to diagnose and monitor Parkinson's disease can improve the quality of life of patients. With the advent of new wearable technologies such as smart rings and watches, this is within reach. However, it is unclear what method for these new technologies may provide the best opportunity to capture the patient-specific severity. This study investigates which locations on the hand can be used to capture and monitor maximal movement/tremor severity. Using a Leap Motion device and custom-made software the volume, velocity, acceleration, and frequency of Parkinson's (n = 55, all right-handed, majority right-sided onset) patients' hand locations (25 joints inclusive of all fingers/thumb and the wrist) were captured simultaneously. Distal locations of the right hand, i.e., the ends of fingers and the wrist showed significant trends (p < 0.05) towards having the largest movement velocities and accelerations. The right hand, compared with the left hand, showed significantly greater volumes, velocities, and accelerations (p < 0.01). Supplementary analysis showed that the volumes, acceleration, and velocities had significant correlations (p < 0.001) with clinical MDS-UPDRS scores, indicating the potential suitability of using these metrics for monitoring disease progression. Maximal movements at the distal hand and wrist area indicate that these locations are best suited to capture hand tremor movements and monitor Parkinson's disease.


Asunto(s)
Enfermedad de Parkinson , Temblor , Mano , Humanos , Movimiento , Enfermedad de Parkinson/diagnóstico , Calidad de Vida , Temblor/diagnóstico
5.
Afr J Reprod Health ; 26(11s): 44-53, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585123

RESUMEN

According to UNAIDS, the 90-90-90 strategy calls for 90% of HIV-infected individuals to be diagnosed by 2020, 90% of whom will be on anti-retroviral therapy (ART) and 90% of whom will achieve sustained virologic suppression. HIV counselling and testing (HCT) is an important entry point for effective prevention of mother-to-child transmission of HIV. However, evidence abounds that HCT is often missed by pregnant women during antenatal care in Nigeria. We used secondary data from the 2018 Nigerian National Nutrition and Health Survey (NNHS) to determine the pattern of missed opportunities within the HCT algorithm and the factors associated with the missed opportunities. Of the 8,329 eligible women, 2,327 (27.9%) missed HCT because of lack of antenatal care; 1,493 (24.9%) missed HIV pre-test counselling; 180 (4.0%) missed HIV testing after participating in pre-test counselling, while 793 (18.2%) missed collection of HIV result and post-test counselling. Generally, most of the women that missed HCT were from the North West (43.3%) and had their antenatal care with traditional birth attendants. The odds of missing ANC were higher in women in the Northern and Southern regions. Concerning pre-test HIV counselling, the odds of missing it were higher among women in the Northwest and Southeast while the odds of missing post-test counselling of HIV test were higher among women in the Northeast and Southeast relative to other regions. Using TBA as a care provider was associated with higher odds of women missing pre-test and post-test counselling of HIV during ANC compared to those that used doctors or midwives or CHEWs. Missed opportunities are common in different stages of HIV counselling and testing pathway in Nigeria, particularly in the Northern regions. Future studies would need to identify the specific reasons for these missed opportunities, enabling the targeting of more specific policy reform and interventions.


Asunto(s)
Infecciones por VIH , Complicaciones Infecciosas del Embarazo , Femenino , Embarazo , Humanos , Mujeres Embarazadas , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/prevención & control , Nigeria , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Atención Prenatal , Consejo , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Encuestas Epidemiológicas
6.
Afr J Reprod Health ; 26(11s): 54-61, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585124

RESUMEN

Globally, malnutrition among under-five children remains a public health concern. There is increasing concern at research and policy levels about anthropometric failure and the double burden of child malnutrition across different groups of children. The objective of this study was to describe the magnitude and distribution of various forms of anthropometric failure (AF) among children under age five in Nigeria. We used the 2018 National Nutrition and Health Survey data collected among 19,471 under-five children in Nigeria. The most prevalent AF was stunting only (17.7%) followed by stunting and underweight (13.9%). Wasting, stunting and underweight was found among 3.5% of the sample. Wasting, stunting and underweight was most common in age 6-11 months (7.0%) and 12-23 months (6.9%). Overall, about 1 out of 5 under-five children has multiple anthropometric failure. The peak age group for multiple AFs was between six months and 35 months. Multiple AF was less likely among females compared to males (RR=0.74, CI: 0.69, 0.80). The risk of multiple AF was higher in both North East (RR=2.15, CI: 1.78, 2.59) and North West (RR=2.98, CI: 2.51, 3.55) relative to the North Central. In contrast, the risk was lesser in the South East (RR=0.75, CI: 0.59, 0.95) and other southern regions. The study showed that multiple anthropometric failure is a common problem among children in Nigeria. Programmes that will support prevention and early identification of different types of malnutrition among under-five children across States in Nigeria are recommended.


Asunto(s)
Desnutrición , Delgadez , Masculino , Femenino , Humanos , Niño , Lactante , Delgadez/epidemiología , Prevalencia , Nigeria/epidemiología , Desnutrición/epidemiología , Trastornos del Crecimiento/epidemiología , Encuestas Epidemiológicas
7.
Afr J Reprod Health ; 26(11s): 62-68, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585125

RESUMEN

In general, family planning uptake promotes healthy living among couples and their children, in addition to aiding national development. This study was a secondary analysis of data collected from two nationally representative data - 2015 and 2018 National Nutrition and Health Surveys (NNHS) - aimed at measuring the uptake of modern and traditional contraceptive methods among women of reproductive age in Nigeria. The data were analysed by presenting differentials in prevalence of modern and traditional contraceptives between 2015 and 2018. The results showed that during the periods modern contraceptive uptake in Nigeria ranged between 10% and 17%. By contrast, the prevalence of the traditional methods was 8.3% and 10.0%. Within four years (2015-2018), the average national modern contraceptive uptake among women increased by 7%, while the traditional contraceptive uptake reduced by 2%. The uptake of both modern and traditional contraceptive methods varied by ages group of women, geo-political regions, and State of residence. We conclude that the uptake of modern contraception is below expectation in all regions in Nigeria. The uptake is worse in the northern regions as compared to the southern regions. Government needs to invest more to increase access to and utilization of modern contraceptive methods.


Asunto(s)
Anticoncepción , Servicios de Planificación Familiar , Niño , Femenino , Humanos , Nigeria , Anticoncepción/métodos , Anticonceptivos , Conducta Anticonceptiva
8.
Afr J Reprod Health ; 26(11s): 77-85, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585127

RESUMEN

Clinical competence of primary healthcare (PHC) workers is important in the delivery of maternal and child health care and services. In this cross-sectional study, we investigated the diagnostic accuracy and adherence to clinical guidelines for the management of some clinical conditions such as malaria, diarrhea, pneumonia, neonatal asphyxia and postpartum hemorrhage, as a proxy to measure the clinical competence of frontline health workers in PHCs in selected states in Nigeria. Ninety PHC facilities were randomly selected in each State and the FCT. Of the 3330 health workers, only 36.0% were able to correctly diagnose the five selected medical conditions. There was a significant difference in the diagnostic accuracy of the health workers with the doctors having highest diagnostic accuracy (65.5%) compared to other health workers (p <0.001). Adherence to the management guidelines was generally poor across all cadres of health workers and this pattern appear similar across the geopolitical regions in the country. The highest adherence to guidelines was observed among medical doctors (38.2%). The diagnostic accuracy and adherence to national guidelines for managing patients was poor among health workers, particularly, among other cadres except doctors. PHC workers in Nigeria need continuous training to enhance their clinical competence to improve quality of maternal and child health care.


Asunto(s)
Salud Infantil , Competencia Clínica , Niño , Recién Nacido , Femenino , Embarazo , Humanos , Nigeria , Estudios Transversales , Personal de Salud
9.
Afr J Reprod Health ; 26(11s): 69-76, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585126

RESUMEN

Despite the availability of healthcare centres for the provision of antenatal care (ANC) services in Nigeria, the services are still underutilized by pregnant women. ANC services not only reduce maternal mortality and birth defects, but also have a strong link to many causes of maternal deaths. This study explored the individual and ecological relationships between antenatal care, skilled birth assistance during delivery, and family planning use across states in Nigeria. This study was a secondary analysis of data from the 2018 National Nutrition and Health Survey (NNHS) carried out among 24,985 women aged 15-49 years in the 36 states and the Federal Capital Territory (FCT) in Nigeria. Analysis was carried out at the level of individual women and at the ecological level. Only 68.3% visited a health professional (doctors, nurses, midwives, community health extension workers, and community health officers) for ANC in the most recent pregnancy before the survey. At delivery, 44.9% were assisted by delivery attendants with about half (50.1%) assisted by non-professional (traditional birth attendants, relatives and friends) during delivery. There was a significant variation in use of modern family planning (FP) across types of ANC provider. There was a strong positive correlation between ANC utilisation and skilled birth attendance (SBA) (r=0.706, p <0.001), and between SBA and FP (r=0.730, p <0.001). These results have implications for the design of appropriate interventions for strengthening the role of healthcare providers to enhance ANC patronage, utilization of safe delivery services and sustained use of reproductive health services.


Asunto(s)
Servicios de Salud Materna , Partería , Embarazo , Femenino , Humanos , Atención Prenatal , Servicios de Planificación Familiar , Nigeria , Parto
10.
Afr J Reprod Health ; 26(11s): 86-97, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585128

RESUMEN

This study used a nationally representative cross-sectional data from 2018 Nigeria Demographic Health Survey (NDHS) to investigate the prevalence and factors associated with anaemia in children aged less than five years in Nigeria. Anaemia was defined as haemoglobin level <11.0g/dl, while explanatory variables included parental profile, social and environmental factors. Descriptive analyses and multivariable Poisson regression models were fitted using Stata 15 software. Associated factors were quantified using Prevalence Ratio (PR) with 95% confidence interval (CI). Of the 5834 children aged 6-59 months, 51.9% were male. The prevalence of anaemia among under-five children was 71.6% (95% CI: 69.9-73.2). Childhood anaemia was associated with history of maternal anaemia (PR 1.06; CI 1.05-1.08); having underweight mothers (PR 1.02; CI 1.00-1.05); being a Muslim (PR 1.05; CI 1.02-1.08), Igbo (PR 1.07; CI 1.01-1.14) and Hausa (PR 1.04; CI 1.01-1.07) ethnic group. Further, children from South-South (PR 1.09; CI 1.06-1.13) and South-West (PR 1.06; CI 1.02-1.10) and those currently breastfeeding (PR 1.06; CI 1.04-1.07) had higher risk of anaemia. However, children from middle (PR 0.94; CI 0.91-0.97), or higher wealth indices were less likely to have anaemia. Maternal socio-economic and nutritional characteristics were identified as key predictors of under-five anaemia. Strategies are needed to mitigate the effect of poverty and tweak new and existing nutritional intervention programs to make them responsive to socio-cultural peculiarities across the various geo-political regions of Nigeria.


Asunto(s)
Anemia , Madres , Femenino , Humanos , Masculino , Niño , Nigeria/epidemiología , Estudios Transversales , Anemia/epidemiología , Lactancia Materna , Prevalencia , Factores de Riesgo , Factores Socioeconómicos
11.
Afr J Reprod Health ; 26(11s): 28-43, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37585122

RESUMEN

Early initiation of breastfeeding (EIBF) is an essential first step in exclusive breastfeeding that is expected to commence within an hour after childbirth. This study examined the prevalence and the factors associated with EIBF among nursing mothers in Nigeria based on an analysis of the 2003, 2008, 2013, and 2018 Nigerian Demographic Health Survey (NDHS) data. The prevalence of early breastfeeding initiation by women's demographic, socio-economic and reproductive characteristics were computed for each of the survey rounds. The differences in the prevalence estimates for early breastfeeding initiation between the last two survey periods were calculated. A crude and adjusted model to examine association between explanatory variables and early breastfeeding initiation were fitted using Poisson regression model. The mean age of respondents was 29 years (SD=7.3). The prevalence of EIBF increased from 31.5% in 2003 (95% CI 28.4-34.5) to 43.8% in 2018 (95% CI 42.6-45.0), with a decline to 35.3% in 2013 (95% CI 34.0-36.7). The identified risk factors associated with EIBF were being 35-39 years, having at least a primary education, lower wealth quintiles, multiparity, and delivery in a public hospital. EIBF was lower among women that had skilled occupation, access to media, decided to delay pregnancy, history of previous caesarean section, small size baby at birth, and women who received antenatal care. The results indicate that the proportion of women with EIBF in Nigeria is low. Addressing the barriers identified in this paper will help promote EIBF practices in the country.


Asunto(s)
Lactancia Materna , Cesárea , Lactante , Recién Nacido , Femenino , Embarazo , Humanos , Adulto , Nigeria/epidemiología , Prevalencia , Factores Socioeconómicos , Factores de Tiempo , Madres
12.
Sensors (Basel) ; 20(21)2020 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-33105890

RESUMEN

(1) Background: Acute acoustic (sound) stimulus prompts a state of defensive motivation in which unconscious muscle responses are markedly enhanced in humans. The orbicularis oculi (OO) of the eye is an easily accessed muscle common for acoustic startle reaction/response/reflex (ASR) investigations and is the muscle of interest in this study. Although the ASR can provide insights about numerous clinical conditions, existing methodologies (Electromyogram, EMG) limit the usability of the method in real clinical conditions. (2) Objective: With EMG-free muscle recording in mind, our primary aim was to identify and investigate potential correlations in the responses of individual and cooperative OO muscles to various acoustic stimuli using a mobile and wire-free system. Our secondary aim was to investigate potential altered responses to high and also relatively low intensity acoustics at different frequencies in both sitting and standing positions through the use of biaural sound induction and video diagnostic techniques and software. (3) Methods: This study used a mobile-phone acoustic startle response monitoring system application to collect blink amplitude and velocity data on healthy males, aged 18-28 community cohorts during (n = 30) in both sitting and standing postures. The iPhone X application delivers specific sound parameters and detects blinking responses to acoustic stimulus (in millisecond resolution) to study the responses of the blinking reflex to acoustic sounds in standing and sitting positions by using multiple acoustic test sets of different frequencies and amplitudes introduced as acute sound stimuli (<0.5 s). The single acoustic battery of 15 pure-square wave sounds consisted of frequencies and amplitudes between 500, 1000, 2000, 3000, and 4000 Hz scales using 65, 90, and 105 dB (e.g., 3000 Hz_90 dB). (4) Results: Results show that there was a synchronization of amplitude and velocity between both eyes to all acoustic startles. Significant differences (p = 0.01) in blinking reaction time between sitting vs. standing at the high intensity (105 dB) 500 Hz acoustic test set was discovered. Interestingly, a highly significant difference (p < 0.001) in response times between test sets 500 Hz_105 dB and 4000 Hz_105 dB was identified. (5) Conclusions: To our knowledge, this is the first mobile phone-based acoustic battery used to detect and report significant ASR responses to specific frequencies and amplitudes of sound stimulus with corresponding sitting and standing conditions. The results from this experiment indicate the potential significance of using the specific frequency, amplitude, and postural conditions (as never before identified) which can open new horizons for ASR to be used for diagnosis and monitoring in numerous clinical and remote or isolated conditions.


Asunto(s)
Teléfono Celular , Postura , Reflejo de Sobresalto , Estimulación Acústica , Adolescente , Adulto , Parpadeo , Electromiografía , Humanos , Masculino , Adulto Joven
13.
Appetite ; 125: 152-159, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29427692

RESUMEN

Researchers have long sought to pinpoint factors underpinning individual differences in eating behaviour. Emerging data from eye-tracking studies have suggested that attentional biases to food exist among individuals and food types. However, such studies have thus far relied on food images and computerised tasks, limiting real-world implications. The present study tested 32 healthy male participants (16 being overweight) for attentional biases in an ad libitum buffet setting, using wearable eye-trackers. The eye-tracking analyses suggested that sugar content moderated visual fixation biases (p < 0.05), whereas BMI exerted significant effects on pupil diameter (p < 0.05). In addition, findings from the study revealed tripartite relationships between eye-tracking, self-reported liking, and ad libitum intake. Although visual fixation in the "view" condition was correlated with liking for high-calorie food, further analyses showed that this measure was not a strong predictor of food selection. Instead, visual fixation during the selection task could be the key predictor for selection of savoury food. In contrast, neither eye-tracking nor self-reported measures could adequately predict selection of desserts, implicating distinct decision-making processes for different types of food. Due to the small sample size, findings from this study should be replicated in future research. Overall, this study highlights the importance of realistic experimental settings in eye-tracking studies for understanding eating behaviour.


Asunto(s)
Conducta de Elección/fisiología , Fijación Ocular/fisiología , Preferencias Alimentarias/fisiología , Sobrepeso/psicología , Delgadez/psicología , Adulto , Sesgo Atencional , Conducta Alimentaria , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
14.
J Cogn Neurosci ; 29(8): 1433-1444, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28387589

RESUMEN

Decisions are made based on the integration of available evidence. The noise in evidence accumulation leads to a particular speed-accuracy tradeoff in decision-making, which can be modulated and optimized by adaptive decision threshold setting. Given the effect of pre-SMA activity on striatal excitability, we hypothesized that the inhibition of pre-SMA would lead to higher decision thresholds and an increased accuracy bias. We used offline continuous theta burst stimulation to assess the effect of transient inhibition of the right pre-SMA on the decision processes in a free-response two-alternative forced-choice task within the drift diffusion model framework. Participants became more cautious and set higher decision thresholds following right pre-SMA inhibition compared with inhibition of the control site (vertex). Increased decision thresholds were accompanied by an accuracy bias with no effects on post-error choice behavior. Participants also exhibited higher drift rates as a result of pre-SMA inhibition compared with the vertex inhibition. These results, in line with the striatal theory of speed-accuracy tradeoff, provide evidence for the functional role of pre-SMA activity in decision threshold modulation. Our results also suggest that pre-SMA might be a part of the brain network associated with the sensory evidence integration.


Asunto(s)
Toma de Decisiones/fisiología , Inhibición Psicológica , Percepción de Movimiento/fisiología , Corteza Motora/fisiología , Ritmo Teta/fisiología , Teorema de Bayes , Mapeo Encefálico , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Modelos Neurológicos , Estimulación Luminosa , Tiempo de Reacción/fisiología , Recompensa , Estimulación Magnética Transcraneal , Adulto Joven
15.
PLoS Comput Biol ; 12(3): e1004825, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27010473

RESUMEN

Metabolic efficiency depends on the balance between supply and demand of metabolites, which is sensitive to environmental and physiological fluctuations, or noise, causing shortages or surpluses in the metabolic pipeline. How cells can reliably optimize biomass production in the presence of metabolic fluctuations is a fundamental question that has not been fully answered. Here we use mathematical models to predict that enzyme saturation creates distinct regimes of cellular growth, including a phase of growth arrest resulting from toxicity of the metabolic process. Noise can drive entry of single cells into growth arrest while a fast-growing majority sustains the population. We confirmed these predictions by measuring the growth dynamics of Escherichia coli utilizing lactose as a sole carbon source. The predicted heterogeneous growth emerged at high lactose concentrations, and was associated with cell death and production of antibiotic-tolerant persister cells. These results suggest how metabolic networks may balance costs and benefits, with important implications for drug tolerance.


Asunto(s)
Puntos de Control del Ciclo Celular/fisiología , Enzimas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/citología , Escherichia coli/crecimiento & desarrollo , Modelos Biológicos , Proliferación Celular/fisiología , Simulación por Computador , Activación Enzimática , Tasa de Depuración Metabólica , Proteínas de Transporte de Monosacáridos/metabolismo , Simportadores/metabolismo , beta-Galactosidasa/metabolismo
16.
Toxicol Ind Health ; 32(7): 1328-34, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25537622

RESUMEN

The aim of this study was to investigate the effects of taurine (TA) on serum lipid profiles following chronic coadministration of chlorpyrifos (CP) and lead acetate (Pb) in male Wistar rats. Fifty rats randomly distributed into five groups served as subjects. Distilled water (DW) was given to DW group, while soya oil (SO; 1 mL kg(-1)) was given to SO group. The TA group was treated with TA (50 mg kg(-1)). The CP + Pb group was administered sequentially with CP (4.25 mg kg(-1); 1/20th median lethal dose (LD50)) and Pb at 233.25 mg kg(-1) (1/20th LD50), while the TA + CP + Pb group received TA (50 mg kg(-1)), CP (4.25 mg kg(-1)), and Pb (233.25 mg kg(-1)) sequentially. The treatments were administered once daily by oral gavage for 16 weeks. The rats were euthanised, and the blood samples were collected at the termination of the study. Sera obtained from the blood samples were analyzed for total cholesterol, high-density lipoprotein cholesterol, triglycerides, and malondialdehyde, and also the activities of serum antioxidant enzymes including superoxide dismutase, catalase and glutathione peroxidase were analyzed. The low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, and atherogenic index were calculated. The results showed that CP and Pb induced alterations in the serum lipid profiles and evoked oxidative stress. TA alleviated the disruptions in the serum lipid profiles of the rats partially by mitigating oxidative stress. It was concluded that TA may be used for prophylaxis against serum lipid disorders in animals that were constantly co-exposed to CP and Pb in the environment.


Asunto(s)
Cloropirifos/toxicidad , Plomo/toxicidad , Taurina/farmacología , Animales , Catalasa/sangre , Cloropirifos/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Glutatión Peroxidasa/sangre , Plomo/sangre , Masculino , Malondialdehído/sangre , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Superóxido Dismutasa/sangre , Triglicéridos/sangre
17.
Malar J ; 13 Suppl 1: 495, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26651480

RESUMEN

BACKGROUND: An initial study of genetic diversity of Plasmodium falciparum in Asembo, western Kenya showed that the parasite maintained overall genetic stability 5 years after insecticide-treated bed net (ITN) introduction in 1997. This study investigates further the genetic diversity of P. falciparum 10 years after initial ITN introduction in the same study area and compares this with two other neighbouring areas, where ITNs were introduced in 1998 (Gem) and 2004 (Karemo). METHODS: From a cross-sectional survey conducted in 2007, 235 smear-positive blood samples collected from children ≤15-year-old in the original study area and two comparison areas were genotyped employing eight neutral microsatellites. Differences in multiple infections, allele frequency, parasite genetic diversity and parasite population structure between the three areas were assessed. Further, molecular data reported previously (1996 and 2001) were compared to the 2007 results in the original study area Asembo. RESULTS: Overall proportion of multiple infections (MA) declined with time in the original study area Asembo (from 95.9 %-2001 to 87.7 %-2007). In the neighbouring areas, MA was lower in the site where ITNs were introduced in 1998 (Gem 83.7 %) compared to where they were introduced in 2004 (Karemo 96.7 %) in 2007. Overall mean allele count (MAC ~ 2.65) and overall unbiased heterozygosity (H e  ~ 0.77) remained unchanged in 1996, 2001 and 2007 in Asembo and was the same level across the two neighbouring areas in 2007. Overall parasite population differentiation remained low over time and in the three areas at FST < 0.04. Both pairwise and multilocus linkage disequilibrium showed limited to no significant association between alleles in Asembo (1996, 2001 and 2007) and between three areas. CONCLUSIONS: This study showed the P. falciparum high genetic diversity and parasite population resilience on samples collected 10 years apart and in different areas in western Kenya. The results highlight the need for long-term molecular monitoring after implementation and use of combined and intensive prevention and intervention measures in the region.

18.
Eur J Dent Educ ; 18(3): 154-61, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24330036

RESUMEN

OBJECTIVES: Knowledge of nicotine replacement therapy (NRT) is a competency that is expected from receiving training in the treatment for tobacco dependence. This study therefore assessed the knowledge of dental students in 43 countries about NRT. METHODS: The 2005-2011 dental Global Health Professions Student Survey data were analysed for 13,040 third-year dental students from 43 countries. Knowledge about NRT was self-reported and country-specific prevalence estimates were calculated. To assess for correlates of knowledge about NRT amongst dental students, a multivariate logistic regression model was fitted (P < 0.05), with pooled data from all 43 countries. The model assessed for geographical location, gross national income, tobacco cessation training in school, sex, current tobacco use and survey year. RESULTS: Amongst all dental students, the proportion that knew about NRT ranged from 37.0% (Mongolia) to 97.6% (Slovakia). The odds of knowing about NRT were lower amongst dental students in the Eastern Mediterranean region (aOR = 0.52; 95% CI: 0.34-0.79) compared to those in the European region. Dental students in upper-middle-income (aOR = 2.46; 95% CI: 1.57-3.85) and high-income countries (aOR=4.55; 95% CI: 2.28-9.09) both had higher odds of knowing about NRT compared to dental students in low-income countries. Also, current use of any tobacco product and receipt of tobacco cessation training in school were both associated with higher likelihood of knowing about NRT. No significant gender differences in knowledge of NRT were observed. CONCLUSIONS: A large proportion of dental students in several countries knew about NRT. However, disparities in knowledge existed across regions. Enhanced efforts are needed to formally train dental students on tobacco cessation techniques.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Estudiantes de Odontología/psicología , Dispositivos para Dejar de Fumar Tabaco , Cese del Uso de Tabaco , Adulto , Educación en Odontología , Femenino , Humanos , Masculino , Autoinforme , Encuestas y Cuestionarios
19.
Afr J Med Med Sci ; 43(3): 195-204, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26223136

RESUMEN

BACKGROUND: Logistic regression model is widely used in health research for description and predictive purposes. Unfortunately, most researchers are sometimes not aware that the underlying principles of the techniques have failed when the algorithm for maximum likelihood does not converge. Young researchers particularly postgraduate students may not know why separation problem whether quasi or complete occurs, how to identify it and how to fix it. OBJECTIVE: This study was designed to critically evaluate convergence issues in articles that employed logistic regression analysis published in an African Journal of Medicine and medical sciences between 2004 and 2013. METHODS: Problems of quasi or complete separation were described and were illustrated with the National Demographic and Health Survey dataset. A critical evaluation of articles that employed logistic regression was conducted. RESULTS: A total of 581 articles was reviewed, of which 40 (6.9%) used binary logistic regression. Twenty-four (60.0%) stated the use of logistic regression model in the methodology while none of the articles assessed model fit. Only 3 (12.5%) properly described the procedures. Of the 40 that used the logistic regression model, the problem of convergence occurred in 6 (15.0%) of the articles. CONCLUSION: Logistic regression tends to be poorly reported in studies published between 2004 and 2013. Our findings showed that the procedure may not be well understood by researchers since very few described the process in their reports and may be totally unaware of the problem of convergence or how to deal with it.


Asunto(s)
Modelos Logísticos , Investigación/estadística & datos numéricos , África , Conjuntos de Datos como Asunto , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Funciones de Verosimilitud , Edición/normas
20.
SADJ ; 69(6): 272-4, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26548202

RESUMEN

There is ongoing debate as to whether persons of different racial/ethnic groups are biologically significantly different, and, if such differences exist, whether they are relevant in relation to disease susceptibility and to treatment outcomes. There is also debate about the benefits of using race/ethnicity as a factor in clinical decision making, and as a variable in biomedical or public health research, because of the emotional sensitivities attached to race/ethnic categorisation. Such categorisation may also divert attention from underlying issues such as socioeconomic status and lack of access to modern health care. In this short article we will discuss these controversies, and will emphasize the importance of responsible and sensitive use of race/ethnicity as a variable in biomedical research and in clinical practice.


Asunto(s)
Investigación Biomédica , Enfermedad/etnología , Etnicidad , Grupos Raciales , Susceptibilidad a Enfermedades/etnología , Escolaridad , Etnicidad/genética , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad/etnología , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Accesibilidad a los Servicios de Salud , Disparidades en Atención de Salud/etnología , Humanos , Prejuicio/etnología , Grupos Raciales/genética , Clase Social , Resultado del Tratamiento
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