Changes in the microvasculature with age

The microvasculature of various organs of the rat and of the mesentery of the cat were examined for histochemical changes as a function of age, using the periodic acid-Schiff (PAS) reaction. Arterioles, minute arteries, and nonmuscular venules were histochemically unchanged to approximately 17 months of age in the rat and 8 years in the cat. Subsequently, focal areas of PAS-positive material developed in the media of arterioles and small arteries and increased in extent and severity with age. The adventitia of nonmuscular venules normally stains slightly positive due to the mucopolysaccharide coating of collagen fibers. With age this adventitial layer becomes more intensely PAS-positive. In the 26-month-old rat and 19-year-old cat, the media of arterioles and small arteries were extensively hyalinized. Lesions of arteriosclerosis were not present. These observations, in consort with prior observations of others in various mammals, indicate that there is a regular systematic alteration of various elements of the microcirculation with age. A possible relationship between these anatomical changes and tissue exchange is considered.     

Follow-up catheterization of patients with myocardial infarction during coronary artery bypass surgery.

Of 197 consecutive patients having aortocoronary bypass grafts over a 30 month period, 38 (19 per cent) had ECG evidence of myocardial infarction. The infarctions occurred more commonly in patients receiving multiple grafts. The infarctions were usually in areas supplied by grafted vessels. The infarctions occurred most often in the inferior wall, even when multiple vessels were grafted. Eleven patients with intraoperative infarction have had repeat postoperative coronary arteriograms. Seven had all grafts patent; three of these patients had hypokinesis of the infarcted wall. Four of the 11 patients had one or more occluded grafts; three of these patients had an area of hypokinesis. We conclude that intraoperative myocardial infarction is a common problem in aortocoronary bypass surgery and is not necessarily caused by graft occlusion.     

Association of diet quality,physical activity,and abdominal obesity with metabolic syndrome z-score in black and white adolescents in the US

Background and aimsMetabolic syndrome (MetS) affects ～10% of adolescents and is associated with cardiometabolic disease risk. The most prevalent MetS component is abdominal obesity. Healthy diet and physical activity (PA) are inversely associated with abdominal obesity and may reduce MetS risk in youth. Our aim was to examine associations of diet, activity, and abdominal obesity with MetS z-score (MetS-z).Methods and resultsAn analysis of National Health and Nutrition Examination Survey (NHANES) 2011–2016 data in adolescents was performed. Healthy Eating Index (HEI)- 2015 scores were calculated for diet quality, PA habits were used to determine alignment with national guidelines, and abdominal obesity was assessed by sagittal abdominal diameter (SAD). MetS-z represented severity or potential risk for MetS. Multivariable regression evaluated the relationships of HEI, SAD and PA with MetS-z. Among 1214 black and white adolescents, SAD was significantly associated with MetS-z [β (95% CI) = 0.17 (0.16, 0.19); P <0.0001] while HEI-2015 components showed associations with MetS-z overall (HEI total, dairy, and sodium scores), and by sex (total, refined grains, dairy for males; added sugar, protein, whole grains for females). Mean HEI-2015 score was 47.4/100 (51.6 using the population-ratio method), and the proportion of adolescents meeting national PA guidelines was 37.6%, yet PA was not a significant predictor of MetS-z.ConclusionsUS adolescents have poor diet quality and fewer than half meet PA guidelines. Strategies for preventing MetS and related conditions in adolescence should focus on weight management – specifically, abdominal fat reduction – with individualized diet counseling.     

Improvement of Risk Prediction After Transcatheter Aortic Valve Replacement by Combining Frailty With Conventional Risk Scores

Objectives

This study sought to evaluate whether frailty improves mortality prediction in combination with the conventional scores.

Effects of thyroxine on Na+,K+-ATPase and norepinephrine turnover in brown adipose tissue of obese (ob/ob) mice

Thyroxine treatment improves some of the defective thermogenic properties of obese (ob/ob) mice. Because brown adipose tissue (BAT) is an important thermogenic organ in mice, effects of thyroxine treatment on Na+, K+-ATPase, a thyroid-hormone responsive enzyme, and on rates of norepinephrine (NE) turnover, an indicator of sympathetic nervous system activity, in BAT of lean and obese mice were evaluated. Female mice, six weeks old, were injected with approximately 4 micrograms thyroxine daily for 2 weeks. Numbers of Na+, K+-ATPase enzyme units in BAT were similar in control lean and obese mice. Thyroxine treatment increased numbers of Na+, K+-ATPase enzyme units by 60% and 100% in lean and obese mice, respectively, indicating that the BAT of obese mice was responsive to thyroxine treatment. Fractional rates of NE turnover were 75% faster in BAT of control lean mice than in obese mice. Thyroxine treatment decreased functional rates of NE turnover in BAT of lean mice by 35%, but had no effect on NE turnover in BAT of obese mice. Rates of NE turnover in heart and pancreas of control lean and obese mice were unaffected by phenotype. Although the decreases in fractional rates of NE turnover in heart (-23%) and pancreas (-11%) of lean mice in response to thyroxine injections were not statistically significant, the calculated rates of NE turnover (fractional rate of NE turnover times the NE content of the organ) in these organs of lean mice were decreased 25% to 30% (P less than 0.05) in response to thyroxine. Thyroxine injections did not affect NE turnover in either heart or pancreas of obese mice.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparisons of prostaglandin vasoactive effects and interactions in the in vivo microcirculation of the rat urinary bladder

A combination of techniques for in vivo transillumination, topical application of vasoactive agents, and direct microscopic observation of microcirculatory responses was utilized to evaluate the vasomotor actions of prostaglandins (PGs) E₁, E₂, F_1α, F_2α, A₁, and A₂ on rat urinary bladder arterioles and venules. The effects of PGE₁ and histamine (HIS) on arteriolar responsiveness to norepinephrine (NE), serotonin (5-HT), and PGF_2α were measured. Histochemical studies were completed to determine the primary site of prostaglandin (PG) metabolic deactivation in the urinary bladder. Arteriolar dilatation occurred with HIS, PGE₁, PGE₂, PGA₁, PGA₂, and PGF_1α, all of which (with the exception of HIS) demonstrated significant dose-related responses. Overall, PGE₁ and PGE₂ were of greatest potency. Significant dose-related arteriolar constriction occurred with NE > PGF_2α > 5-HT (in order of decreasing potency). HIS, PGE₁, PGE₂, and PGA₁ produced significant venular dilatation; PGE₁ and HIS were dose related. Only NE resulted in significant venoconstriction. Arteriolar responsiveness to NE and PGF_2α decreased after pretreatment with PGE₁ but was unchanged by HIS pretreatment, whereas application of 5-HT following pretreatment with PGE₁ or HIS produced equivalent levels of arteriolar constriction. The primary site of deactivation of PGE₁ was histochemically localized to bundles of smooth muscle fibers in the muscular coat of the rat urinary bladder wall.     

Relationship between urinary cotinine and serum vitamin A levels in Korean adults: the Korea National Health and Nutrition Examination Survey (KNHANES), 2016–2018

ObjectiveTo examine the relationship between urinary cotinine and serum vitamin A levels in Korean adults.MethodsA total of 4445 adults (age ≥19 years) participating in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2016 to 2018 were classified by sex and as smokers/electronic cigarette users (SE) or non-smokers (NS). Data were analyzed using complex sample general linear models.ResultsThere were no differences in dietary intake of vitamin A, carotene, or retinol between the SE and NS groups. Adjusted mean serum vitamin A levels were higher in the SE group compared with those in the NS group (0.63 mg/L vs 0.60 mg/L among men; 0.55 mg/L vs 0.51 mg/L among women). Among all participants, urinary cotinine and serum vitamin A levels were positively correlated (R² = 0.037). However, no correlation was observed in either the SE or NS groups individually. In a model adjusted for age, body mass index, sex, frequency of binge drinking, and dyslipidemia, a stronger correlation was observed (R² = 0.244).ConclusionIn Korean adults, urinary cotinine levels were positively associated with serum vitamin A levels. Mean serum vitamin A levels were significantly higher in the SE group compared with the NS group.     

The relationship between positive and negative automatic thought and activity in the prefrontal and temporal cortices: A multi-channel near-infrared spectroscopy (NIRS) study

Background

Recently, neurobiological studies of the cognitive model of depression have become vastly more important, and a growing number of such studies are being reported. However, the relationship between the proportion of positive and negative automatic thought and activity in the prefrontal and temporal cortices has not yet been explored. We examined the relationship between brain activity and the proportion of positive and negative automatic thought in patients with major depressive disorder (MDD), using multi-channel near-infrared spectroscopy (NIRS).

Methods

We recruited 75 individuals with MDD (36 females; mean age=39.23±12.49). They completed the Hamilton Rating Scale for Depression, Automatic Thoughts Questionnaire-Revised, Japanese version of the National Adult Reading Test, and the State-Trait Anxiety Inventory. Brain activation was measured by 52-channel NIRS.

Results

We found that activation in the vicinity of the right superior temporal gyrus is related to a deviation to negative of the proportion of positive and negative thoughts in individuals with MDD. Left dorsolateral prefrontal cortex activity was higher in the group with comparatively frequent positive thought.

Limitations

Our participants were patients taking antidepressant medication, which is known to influence brain activity. Second, the poor spatial resolution of NIRS increases the difficulty of identifying the measurement position.

Conclusions

We found that activation of the prefrontal and temporal cortices is related to the proportion of automatic thoughts in the cognitive model of depression.     

青少年早中期焦虑的发展及其与未来规划的关系:追踪研究

目的:探讨青少年早中期焦虑的发展特点及其与未来规划的动态关系。方法:从山东省选取8年级和10年级的学生共1077人作为追踪样本,采用状态—特质焦虑量表和未来规划问卷进行测查。运用交叉滞后回归分析考察了两变量之间的因果关系。结果:①在两次测量中,青少年中期的特质焦虑和状态焦虑水平均高于青少年早期;在间隔一年半的两次测量中,青少年早期的焦虑水平有所上升,青少年中期的焦虑水平保持相对稳定。②在焦虑和未来规划的纵向关系中,前测的状态焦虑和特质焦虑均负向预测后测的教育探索、教育投入、职业探索和职业投入;仅前测教育投入可以负向预测后测状态焦虑。结论:在青少年早中期,焦虑可以看作是个体未来规划的前因变量。     

虚拟现实技术对弱视儿童视功能的影响

目的探讨虚拟现实技术在弱视儿童视功能检查与治疗中的临床效果。方法选取医院2019年5月—2020年3月经检查收治的100例弱视患儿(200只眼)为研究对象,按照基础资料组间均衡可比的原则分为对照组和观察组,各组50例(100眼)。对照组实施国际标准视力表进行常规远近视力检查及传统治疗方法,观察组在对照组基础上实施虚拟现实技术,比较两组患儿治疗后视功能水平。结果治疗后观察组患儿在同时视功能方面与对照组差异无统计学意义(P>0.05);观察组在融合、立体视功能、动态立体视功能方面明显优于对照组,差异有统计学意义(P<0.05)。结论对弱视患儿视功能检查与治疗过程采用虚拟现实技术,可有效提升检查及治疗效果,改善视功能。