The influence of fasting and energy restricting diets on IGF-1 levels in humans: A systematic review and meta-analysis

BackgroundFasting and energy restricting diets have a potential means of delaying or preventing the onset of a range of age-related metabolic and neoplastic diseases. Consistently at the centre of this effect appears to be a significant reduction in circulating IGF-1 levels. The aim of the current systematic review and meta-analysis was to determine the influence of fasting and energy restriction on IGF-1 levels in human subjects.MethodsA comprehensive systematic search was conducted from onset of the database to February 2019 in Embase, MEDLINE/PubMed, and SCOPUS to identify randomized clinical trials that investigating the impact of fasting or energy restriction circulating IGF-1 levels. Effect size was reported as weighted mean difference (WMD) and 95% confidence intervals (CI) using a random-effects models. Subgroup analysis was performed to identify the probable source of heterogeneity among trials.ResultsTotal pooling of fasting and energy restriction randomised controlled trials in WMD analysis revealed no significant effect on circulating IGF-1 levels (WMD: −16.41 ng/ml, 95% CI: −35.88, 3.07). Sub grouped analysis fasting regimens appeared to substantially reduce IGF-1 (WMD: -28.87 ng/ml, 95% CI: −43.69, −14.05, I² = 00%), energy restricting regimens failed to do the same (WMD: -10.98 ng/ml, 95% CI: −33.08, 11.11, I² = 90%). Within this final subgrouping, it was observed that only energy restriction regimens of 50% or greater of normal daily energy intake were capable of significantly reducing IGF-1 levels (WMD: -36.57 ng/ml, 95% CI: −59.19, −13.95, I² = 00%). Finally, a meta regression were noted in which the percentage restriction of daily energy intake inversely correlated with plasma IGF-1 levels (p = 0.04).ConclusionThis study uncovered that fasting significantly reduced levels of IGF-1, while energy restriction diets were successful only when intake was reduced by 50% or more.     

Objective sleep disturbance is associated with poor response to cognitive and behavioral treatments for insomnia in postmenopausal women

Study objectivesTo determine whether insomnia patients with objective sleep disturbance are less responsive to cognitive and behavioral treatments than those without objective sleep disturbance, characterize effects of insomnia therapy on objective sleep, and determine whether reductions in nocturnal cognitive arousal correspond to changes in objective sleep.MethodsSecondary analysis of a single-site, randomized controlled trial. 113 postmenopausal women (56.40 ± 5.34 years) with menopause-related insomnia disorder were randomized to three treatment conditions: cognitive-behavioral therapy for insomnia (CBTI), sleep restriction therapy (SRT), or sleep education control. Primary outcomes were the Insomnia Severity Index (ISI) and polysomnography (PSG) sleep parameters and were collected at pretreatment, posttreatment, and six-month follow-up.ResultsPatients with lower pretreatment PSG sleep efficiency had lower rates of insomnia remission after active treatment relative to those with higher sleep efficiency (37.8% vs 61.8%). Neither CBTI and SRT produced clinically meaningful effects on PSG sleep. Exploratory analyses revealed that reductions in nocturnal cognitive arousal were associated with decreases in PSG sleep latency, but not wake after sleep onset.ConclusionsOur findings support an emerging literature suggesting that insomnia patients with objective sleep disturbance may have blunted response to insomnia therapy. Research is needed to enhance treatments to better improve insomnia in patients with objective sleep disturbance. A lack of observed CBTI and SRT effects on PSG sleep suggests that these therapies may be presently ill-designed to improve objective sleep. Nocturnal cognitive arousal may represent an entry point to improve objective sleep latency in insomnia.NameBehavioral Treatment of Menopausal Insomnia: Sleep and Daytime Outcomes. URL: clinicaltrials.gov. Registration: NCT01933295.     

表没食子儿茶素-3-没食子酸酯对宫内生长受限大鼠肝脏脂代谢的影响和机制

目的 探讨表没食子儿茶素-3-没食子酸酯（EGCG）对宫内生长受限（IUGR）大鼠肝脏脂代谢的影响和机制。方法 采用母鼠孕期全程限食法建立IUGR大鼠模型，随机分为IUGR组和EGCG组，EGCG组大鼠在离乳后用含EGCG的饮用水喂养至10周，同时设立正常对照组，每组8只。13周龄时，测量各组大鼠体重后，采集大鼠血液及肝脏组织标本，检测各组大鼠血清空腹总胆固醇（TC）、甘油三酯（TG）、游离脂肪酸（FFA）、血糖（FPG）、胰岛素（FINS）和肝脏脂质水平，计算稳态模型评估胰岛素抵抗（HOMA-IR）和脂肪组织胰岛素抵抗（adipo-IR），观察肝脏组织病理切片，并采用实时荧光定量PCR法检测肝脏相关基因的相对表达水平。结果 13周龄时，各组大鼠体重比较差异无统计学意义（P=0.067）。各组间的FPG、FFA、FINS、HOMA-IR和adipo-IR水平比较差异均有统计学意义（P < 0.05）。各组间的血清TC和TG水平比较差异无统计学意义（P > 0.05），但在肝脏中IUGR组TC和TG水平均明显高于EGCG组（P < 0.05）。油红染色结果提示，IUGR大鼠的肝脏脂肪储积明显增加，而EGCG能够改善该现象。PCR结果显示，与对照组相比，IUGR组的Ampk mRNA及Adipor1 mRNA表达水平降低，Srebf1 mRNA表达水平增加（P < 0.05），EGCG能逆转IUGR大鼠Ampk mRNA及Srebf1 mRNA的表达水平，且与对照组比较差异无统计学意义（P > 0.05）。结论 早期EGCG干预可能通过Ampk/Srebf1通路下调脂肪酸的从头合成，并通过改善肝细胞的胰岛素抵抗，从而降低IUGR大鼠的肝脏脂肪积累。     

Does the video head impulse test replace caloric testing in the assessment of patients with chronic dizziness? A systematic review and meta-analysis

IntroductionCaloric testing is the most frequently used test to assess peripheral vestibular function since the beginning of the 20th century. However, the video head impulse test, vHIT, has gained prominence in the field of neurotology, as it is a faster examination, easier to perform and less uncomfortable for the patient.ObjectiveTo compare, through systematic review and meta-analysis, the proportion of altered cases between vHIT tests and caloric testing in patients with chronic dizziness, in addition to assessing the sensitivity and specificity of vHIT, with caloric testing as the gold standard.MethodsThe literature search was carried out in the PubMed, Scopus, BVS-Bireme, Web of Science, Embase, Cochrane and ProQuest indexed databases, with no restrictions regarding the publication period. All articles that contained the results of the two tests were included in the evaluation of patients with dizziness. Two researchers independently conducted data selection and extraction from the studies, strictly following the inclusion and exclusion criteria defined in the research protocol. In case of disagreement during the selection, a discussion was carried out with a third evaluator.ResultsEleven of the 1293 initial articles met the eligibility criteria and were analyzed. 2670 patients were evaluated, of which 1112 (41.6%) were males and 1558 (58.4%) females, with a mean age of 51.6 years. The proportion of altered results in the vHIT was 21% (95%CI 9% –33%), and 55% in the caloric testing (95%CI 43% –67%).ConclusionThe vHIT does not substitute for caloric testing. The tests are complementary in assessing the patient with dizziness, as they describe the tonotopy of the ampullary crest at different frequency ranges of stimulation. In chronic cases, the vHIT has a low sensitivity and high diagnostic specificity in comparison to caloric testing.     

The continuum of hip range of motion: From soft-tissue restriction to bony impingement

Traditional studies of hip kinematics have not identified which anatomic structures limit the range of motion (ROM) when the hip is placed in different maneuvers. In this study, we attempted to answer two questions: (a) During which maneuvers is the motion of the hip limited by bony impingement between the femur and pelvis? (b) When is hip ROM determined by the constraint of soft tissues and to what extent? ROM of eight cadaveric hips was measured in 17 maneuvers using a motion capture system. The maneuvers were recreated in silico using 3D CT models of each specimen to detect the occurrence of bony impingement. If bony impingement was not detected, the variable component of 3D hip motion was increased until a collision was detected. The difference between the virtual ROM at the point of bony impingement and the initial ROM measured experimentally was termed as the soft-tissue restriction. The results showed that bony impingement was present in normal hips during maneuvers consisting of high abduction with flexion, and high flexion combined with adduction and internal rotation. At impingement-free maneuvers, the degree of soft tissue restriction varies remarkably, ranging from 4.9° ± 3.8° (internal rotation) at 90° of flexion to 80.0° ± 12.5° (internal rotation) at maximum extension. The findings shed light on the relative contributions of osseous and soft tissues to the motion of the hip in different maneuvers and allow for a better understanding of physical exams of different purposes in diagnosing bone- or soft tissue-related diseases.