Discordance of physiological and biochemical response to smoking and to psychological stress

Both smoking and psychological stress produce marked effects upon cardiovascular function, and several studies have demonstrated that in combination they produce additive or potentiating effects. More recently, it has been reported that individuals strongly reactive to psychological stress are also strongly reactive to nicotine. In an attempt to replicate and extend those findings, we examined reactivity to smoking and competitive mental arithmetic across several physiological and biochemical variables. Despite stable responding across mental arithmetic trials, we were unable to demonstrate significant correlations between reactivity to smoking and to a psychological stressor. We further observed that anxiety level, when low, was a poor predictor of desire to smoke and of withdrawal, whereas higher anxiety levels were more tightly linked to these measures. These findings have implications for the iDen tification of individuals at risk of cardiovascular disease as well as for the design of smoking treatment and relapse prevention programs.     

Application of radioimmunoassay to the renin-angiotensin system and to aldosterone

Many of the factors regulating the renin-angiotensin system have been defined by means of a bioassay method based on the hypertensive effect, in the nephrectomized rat, of angiotensin II generated by the action of renin on its plasma substrate. The bioassay has now been largely replaced by a simpler and more sensitive radioimmunoassay based on the generation of angiotensin I in the same system. The radioimmunoassay of aldosterone in plasma has been possible using antisera developed to aldosterone-albumin conjugates. Cross-reactivity to other steroids is low, but their greater abundance in plasma necessitates chromatographic purification before the immunoassay step. The radioimmunoassay of aldosterone in plasma is simpler and more sensitive than measurement by double isotopic techniques. Simultaneous measurement of renin activity and aldosterone in plasma, now possible by radioimmunoassay, should provide a more precise definition of the interrelationship of the two hormonal systems.     

Ventilatory responses of aged male and female rats to hypercapnia and to hypoxia

Ventilatory parameters such as tidal volume, minute ventilation (VE), and inspiratory flow rate decrease in 24- vs. 12-month-old male and female rats. Differences between male and female values are maintained with age. Ventilatory response male and female rats exhibit to hypercapnia is altered by a decrease of the intercept, but not the slope value. The pattern of breathing exhibited by young females and males in response to hypercapnia (i.e. an increase of VT and f) is different than that noted in old males and females (i.e. an increase in VT only). In contrast, the ventilatory response both of slope and intercept male rats show by 24 months is decreased compared to the 12-month value; but the slope value is actually increased in the older vs. younger female rats in response to hypoxia.     

Adaptation to chronic illness and disability and its relationship to perceptions of independence and dependence

This study extends research on living with chronic physical illness and disability by examining how adaptation processes are associated with different activity domains and how the combination of adaptations and activity domains relate to older adults' perceptions of their independence and dependence, helplessness, emotional reactivity, and coping efficacy. The study investigated the behavioral efforts that 286 older adults with osteoarthritis and/or osteoporosis used to adapt to disability arising from their condition. The findings revealed that adults used a wide range of adaptations, including compensations for loss, optimizing performance, limiting or restricting activities, and gaining help from others. The relative use of each of these adaptations varied across 5 domains of activity: personal care, in-home mobility, community mobility, household activities, and valued activities. Moreover, older adults' perceptions of their independence, dependence, helplessness, emotional reactivity, and coping efficacy varied depending on the domain of activity examined and the type of adaptation used.     

Identification of barriers to insulin therapy and approaches to overcoming them

Poor glycaemic control in type 2 diabetes (T2D) is a global problem despite the availability of numerous glucose‐lowering therapies and clear guidelines for T2D management. Tackling clinical or therapeutic inertia, where the person with diabetes and/or their healthcare providers do not intensify treatment regimens despite this being appropriate, is key to improving patients’ long‐term outcomes. This gap between best practice and current level of care is most pronounced when considering insulin regimens, with studies showing that insulin initiation/intensification is frequently and inappropriately delayed for several years. Patient‐ and physician‐related factors both contribute to this resistance at the stages of insulin initiation, titration and intensification, impeding achievement of optimal glycaemic control. The present review evaluates the evidence and reasons for this delay, together with available methods for facilitation of insulin initiation or intensification.     

Binding of iodinated rat and ovine prolactins to prolactin receptors and to its antibodies

Most studies of prolactin receptors in rat tissues have not used the homologous 125I-labeled rat prolactin as tracers, but rather 125I-labeled ovine or human prolactin. We have compared the effect of different methods of iodination on the specific binding of rat and ovine prolactin to sites in the seminal vesicle of rats and the liver of mice post-partum. Ovine prolactin, either iodinated with lactoperoxidase or with mild chloramine-T (10 micrograms), showed 3 times the specific binding of correspondingly-iodinated rat prolactin. This greater sensitivity of rat prolactin to oxidative damage during iodination, as compared with ovine prolactin is further shown by the difference in Sephadex G-100 elution constant of unlabeled and labeled rat prolactin. .This difference was absent in the case of ovine prolactin. Parallel studies of the binding of the labeled hormone to homologous antibody revealed that immunoreactivity of labeled ovine prolactin was not affected by any of the iodination methods. Rat-prolactin immunoreactivity was depressed by lactoperoxidase iodination as compared with chloramine-T iodination. Rat prolactin was also less potent than ovine prolactin in inhibiting the binding of homologous and heterologous labeled hormone to its receptors, to a larger degree than could be expected from the bioassay potency of the various hormone preparations. These results reflect the greater sensitivity to damage of the biologically active site of rat prolactin, as compared with the ovine hormone.     

不同HBV基因型感染慢性乙型肝炎患者对核苷(酸)类药物治疗的应答反应比较

目的研究与探讨HBV基因型与慢性乙型肝炎患者肝组织病理学变化及对核苷(酸)类抗病毒药物疗效的关系。方法随机将慢性HBV感染者541例分为4组:拉米夫定组136例、替比夫定组135例、恩替卡韦组135例和阿德福韦组135例,各治疗48周。治疗前应用聚合酶链反应法确定HBV基因型,并于治疗前和治疗48周时分别检测肝功能、HBV DNA和HBV M。其中109例行肝组织病理学检查。结果本组HBV B基因型94例(17.38%),C型410例(75.79%),B/C混合型37例(6.84%),未检出其他基因型;在B型感染者,肝组织G3占37.3%、S313.0%,C型感染者G3占8.7%、S3占22.7%,B基因型与C基因型之间比较,有统计学意义(P<0.05);在拉米夫定、恩替卡韦和替比夫定治疗患者,B型、C型和B/C混合型之间疗效的比较,有统计学差异(P<0.05),而在阿德福韦酯治疗患者,几种不同的基因型感染患者疗效无统计学差异(P>0.05)。结论 HBV基因型与患者肝组织病理学改变及对核苷类抗病毒治疗的疗效密切相关。     

The surgical approach to management of pediatric obesity: When to refer and what to expect

Weight loss surgery is recommended for adult patients with morbid obesity and has been used on a case by case basis in the pediatric population. Surgery, however, is just a tool added to the two mainstays of therapy for obesity: 1.) controlled dietary intake and 2.) increases in activity and exercise behaviors. For the pediatric population, the health consequences of obesity are profound with increased cardiovascular risk during adolescence and increased mortality in adulthood. Currently accepted guidelines for weight loss surgery referral use BMI cut points that are the same as for adults: BMI ≥ 35 kg/m² and serious comorbidities of obesity or BMI ≥ 40 kg/m² with minor comorbidities of obesity. A multidisciplinary approach to weight management must be utilized, and a lifetime of follow-up must be addressed. The most commonly performed operations for obesity are laparoscopic adjustable gastric banding (LAGB) and laparoscopic Roux-en-Y gastric bypass (LRYGB). LAGB is safer and does not permanently alter gastrointestinal continuity; however, LAGB is not currently approved for implantation in adolescent patients. LRYGB involves a complex, permanent altering of the gastrointestinal anatomy and is associated with more complications around the time of surgery and is not subject to FDA approval because there is no associated implant. In each operation, appetite is suppressed by construction of a virtual (LAGB) or real (LRYGB) pouch. The dynamics and speed of appetite suppression and, consequently, weight loss are typically different for each operation though longer-term outcomes may be similar. Short- and long-term risks of surgery must be carefully weighed against the benefits of the associated weight loss for each patient. The patient must be empowered to understand the importance of lifestyle and behavior in achieving long-term health.