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991.
The aim of the study was threefold: (a) to test a before-school physical activity intervention (Active-Start) on academic performance, selective attention, and concentration capacity; (b) to test the effect of the Active-Start intervention on anthropometry, body composition, and physical fitness parameters; and (c) whether the physical fitness components are moderators of the effect of the Active-Start program on academic performance, selective attention, and concentration capacity in Chilean children. The Active-Start intervention was a RCT which comprised 170 children (8-10 years old) from three public schools with low socioeconomic status from the city of Santiago (Chile). The exercise intervention was delivered daily, before starting the first school-class (8:00-8:30 am ) for 8 weeks. Changes in academic performance, selective attention and concentration capacity, anthropometric, body composition, and physical fitness parameters were measured. The analyses used were mixed regression models for repeated measures over time. No statistically significant changes in attention and concentration capacity were found. However, significant changes were seen in language (0.63; 95% CI 0.49-0.77) and mathematics (0.49; 95% CI 0.32-0.66) performance (P < .001). Also, improvements were seen in fat mass, fat-free mass, muscular, and cardiorespiratory fitness (all P < .05). The Johnson-Neyman technique revealed a significant relationship between the effect of intervention and attention and concentration when change in cardiorespiratory fitness was above, but not below, 3.05 and 0.70 mL/kg/min, respectively. Implementing before-school physical activity programs such as the Active-Start to enhance the cardiorespiratory fitness may benefit attention capacity and academic success among schoolchildren.  相似文献   
992.
The aim of the study was twofold: (a) to examine the association between health-related physical fitness and attention capacity in Latin American children and adolescents with overweight and obesity and (b) to test whether body composition outcomes are moderators of this association. A cross-sectional design was used to study 201 overweight/obese participants (12.1 ± 2.1 years of age; 34.3% girls) from Chile (Active-Start study) and Colombia (HEPAFIT study). Body composition, muscular fitness, speed-agility, and cardiorespiratory fitness were evaluated using two similar test batteries (ALPHA and FUPRECOL). Attention capacity was measured by the d2 Test. Linear regression and moderation analyses were conducted. Linear regression analysis revealed an association between muscular fitness (β = 0.245, P = .015), speed-agility (β = −0.16, P = .027), cardiorespiratory fitness (β = 0.331, P < .001) and overall fitness score (β = 0.210; P = .004) and attention capacity (all analyses were controlled for age, sex, peak height velocity, maternal education, and study setting). Moderation analysis using the Johnson-Neyman technique revealed that the effect of the relationship between muscular fitness score and speed-agility and attention capacity was stronger as fat mass and fat mass index increased. In conclusion, physical fitness components are associated with higher attention capacity in youth with overweight/obesity, but body composition seems to moderate these relationships. Randomized controlled trials in this population would help to better understand whether improvements in different components of physical fitness lead to better attention capacity, especially in youth with excess adiposity.  相似文献   
993.
994.
995.
Background: Acute radiation enteritis is a common adverse effect related to radiotherapy (RT). Glutamine is an immune modulator and antioxidant amino acid that can exert a protective role in patients receiving abdominal or pelvic radiation. The aim of this study was to test if glutamine prevents radiation enteritis during RT. Materials and Methods: Double‐blind, randomized, controlled trial including 69 patients who needed RT because of pelvic or abdominal malignancies and received glutamine (30 g/d) or placebo (casein, 30 g/d). Enteritis was evaluated according to the Radiation Therapy Oncology Group scale, intestinal inflammation using fecal calprotectin, and gut integrity with citrulline. The incidence of enteritis was analyzed by Kaplan‐Meier curves, and the hazard ratio (HR) was calculated using Cox regression. Results: Patients were predominantly male (65.2%), with an average (SD) age of 66.6 (9.9) years, with urologic (44.9%), rectal (24.6%), or gynecological cancer (23.1%). More patients developed enteritis with glutamine than with the placebo (55.9% vs 22.0%; P = .002), with an HR of 1.59 (95% confidence interval, 0.62–4.05). There were no differences in final calprotectin levels (glutamine, 57.9 [85.8] mg/kg vs placebo, 54.0 [57.7] mg/kg; P = .182) or the number of patients with values >50 mg/kg (glutamine, 58.1% vs placebo, 54.6%; P = .777). Final citrulline levels were similar between groups (glutamine, 26.31 [10.29] mmol/L vs placebo, 27.69 [12.31] mmol/L; P = .639), without differences in the number of patients with <20 mmol/L (glutamine, 24.1% vs placebo, 25.0%; P = .938). Citrulline concentration was reduced during RT with placebo but remained unchanged with glutamine. Conclusion: Glutamine does not prevent the development of enteritis during RT.  相似文献   
996.

Introduction

The objective of this article is to present the rationale and baseline results for a randomized controlled pilot trial using economic incentives to reduce HIV and sexually transmitted infection (STI) risk among male sex workers (MSWs) in Mexico City.

Methods

Participants (n=267) were tested and treated for STIs (chlamydia, gonorrhoea, syphilis and HIV) and viral hepatitis (hepatitis B and C), received HIV and STI prevention education and were randomized into four groups: (1) control, (2) medium conditional incentive ($50/six months), (3) high conditional incentive ($75/six months) and (4) unconditional incentive ($50/six months). In the conditional arms, incentives were contingent upon testing free of new curable STIs (chlamydia, gonorrhoea and syphilis) at follow-up assessments.

Results

Participants’ mean age was 25 years; 8% were homeless or lived in a shelter, 16% were unemployed and 21% lived in Mexico City less than 5 years. At baseline, 38% were living with HIV, and 32% tested positive for viral hepatitis or at least one STI (other than HIV). Participants had a mean of five male clients in the previous week; 18% reported condomless sex with their last client. For 37%, sex work was their main occupation and was conducted mainly on the streets (51%) or in bars/discotheques (24%) and hotels (24%). The average price for a sex transaction was $25 with a 35% higher payment for condomless sex.

Conclusions

The findings suggest that economic incentives are a relevant approach for HIV prevention among MSWs, given the market-based inducements for unprotected sex. This type of targeted intervention seems to be justified and should continue to be explored in the context of combination prevention efforts.  相似文献   
997.

INTRODUCTION

Bochdalek hernia presentation in adulthood is rare. The presentation in newborns is the most common, manifesting with data from respiratory failure secondary to pulmonary hypoplasia, requiring urgent surgical intervention with high morbidity and mortality.

PRESENTATION OF CASE

We present the case of a 33 year old woman admitted in the emergency room with severe abdominal pain in the left upper quadrant and disnea. After physical examination and laboratory test we diagnose mild acute pancreatitis. The patient haven’t colelitiasis by ulstrasound or any risk factor for pancreatitis. Initially she received medical treatment and was discharged after one week. After four weeks she presented the same symptoms in two different occasions, with severe and mild pancreatitis respectively. A computed tomography report a left posterolateral diafragmatic hernia. In spite of the rare association of pancreatitis and Bochdalek hernia, we realized it as the etiology until the second event and planned his surgery. We made a posterolateral torachotomy and diafragmatic plasty with a politetrafluoroetileno mesh and after a 6 months follow up she has coursed asymptomatic.

DISCUSSION

The high rate of complications in this type of hernia requires us to perform surgical treatment as the hernia is detected. In this case it is prudent medical treatment prior to surgical correction despite this being the origin of the pancreatitis, because the systemic inflammatory response added by the surgical act could result in a higher rate of complications if not performed at the appropriate time. There is no precise rule to determine the type of approach of choice in this type of hernia which thoracotomy or laparotomy may be used.

CONCLUSION

Bochdalek hernia is a rare find in adults who require treatment immediately after diagnosis because of the high risk of complications. When presented with data from pancreatitis is recommended to complete the medical treatment of pancreatitis before surgery to obtain the best results, unless it exist another abdominal complication.  相似文献   
998.

OBJECTIVE:

to describe the experience of Latin American working women regarding immigration, taking into account the expectations and conditions in which this process takes place.

METHOD:

ethnographic qualitative study. Data collection was performed by means of semi-structured interviews with 24 Latin American immigrant women in Spain. The information collected was triangulated through two focal groups.

RESULTS:

the expectations of migrant women focus on improving family living conditions. Social support is essential for their settling and to perform daily life activities. They declare they have adapted to the settlement country, although they live with stress. They perceive they have greater sexual freedom and power with their partners but keep greater responsibility in childcare, combining that with the role of working woman.

CONCLUSIONS:

migrant women play a key role in the survival of households, they build and create new meanings about being a woman, their understanding of life, their social and couple relationships. Such importance is shaped by their expectations and the conditions in which the migration process takes place, as well as their work integration.  相似文献   
999.
Current knowledge concerning the molecular mechanisms of the cellular response to excitotoxic insults in neurodegenerative diseases is insufficient. Although glutamate (Glu) has been widely studied as the main excitatory neurotransmitter and principal excitotoxic agent, the neuroprotective response enacted by neurons is not yet completely understood. Some of the molecular participants have been revealed, but the signaling pathways involved in this protective response are just beginning to be identified. Here, we demonstrate in vivo that, in response to the cell damage and death induced by Glu excitotoxicity, neurons orchestrate a survival response through the extracellular signal-regulated kinase (ERK) signaling pathway by increasing ERK expression in the rat hippocampal (CA1) region, allowing increased neuronal survival. In addition, this protective response is specifically reversed by U0126, an ERK inhibitor, which promotes cell death only when it is administered together with Glu. Our findings demonstrate that the ERK signaling pathway has a neuroprotective role in the response to Glu-induced excitotoxicity in hippocampal neurons. Therefore, the ERK signaling pathway may be activated as a cellular response to excitotoxic injury to prevent damage and neural loss, representing a novel therapeutic target in the treatment of neurodegenerative diseases.  相似文献   
1000.

Purpose

Determine the structure of depressive symptoms among adolescents and older adults through the person-centered approach of latent class analysis (LCA).

Methods

The study is based on data from two independent samples collected in Mexico City (2,444 adolescents and 2,223 older adults) which included the revised version of the CES-D. The presence or absence of depressed mood (dysphoria), diminished pleasure (anhedonia), drastic change in weight, sleep problems, thinking and concentration difficulties, excessive or inappropriate guilt, fatigue, psychomotor agitation/retardation, and suicide ideation were used in LCA to determine the structure of depressive symptoms for adolescents and older adults.

Results

Adolescents reported higher excessive or inappropriate guilt compared to older adults, while older adults had higher proportions of anhedonia, sleep problems, fatigue, and psychomotor agitation/retardation. Similar proportions were found in other symptoms. The LCA analysis showed the best fit with four latent classes (LC): LC 1, “symptoms suggestive of major depressive episode (MDE)” with prevalence of 5.9 % (n = 144) and 10.3 % (n = 230) among adolescents and older adults, respectively; LC 2, “probable MDE symptoms” 18.2 % (n = 446) and 23.0 % (n = 512); LC 3, “possible MDE” 27.7 % (n = 676) and 21.8 % (n = 485); LC 4, “without significant depressive symptoms” 48.2 % (n = 1,178) and 44.8 % (n = 996). The differences in item thresholds between the two groups (adolescents vs. older adults) were statistically significant (Wald test = 255.684, df = 1, p < 0.001).

Conclusions

This study documented important similarities and differences in the structure of depressive symptoms between adolescents and older adults that merit acknowledgment, further study, and consideration of their potential clinical and public health implications.  相似文献   
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