RBC volume deficiency in patients with excessive orthostatic decrease in cerebral blood flow velocity

BackgroundOrthostatic intolerance (OI) is common but heterogeneous. There is a subgroup of OI patients who have excessive decrease in cerebral blood flow velocity (CBFV) of bilateral middle cerebral arteries (MCAs) during head-up tilt without systemic blood pressure change. This study evaluated the role of blood volume reduction in such patients.MethodsPatients with idiopathic OI who had excessive orthostatic decrease (>20% of the supine level) in mean CBFV of bilateral MCAs and who also received blood volume determination were collected. The chromium (⁵¹Cr) dilution method was used for red blood cell (RBC) volume determination in these patients. The blood volume was expressed as a percentage of the expected volume. These patients were further divided into two groups, those with postural tachycardia syndrome (POTS group) and those without (non-POTS group). The data of RBC volume were compared between the two groups. Besides, we used multivariate linear regression to evaluate the factors that predict RBC volume.ResultsTwenty-five patients (13 females, median age = 28 years) were enrolled in this study. Nine of these patients had POTS (5 females, median age = 26 years) and 16 did not (8 females, median age = 29.5 years). Compared with the expected volume, the RBC volume was significantly reduced in all patients (median = 82% of the expected volume). Moreover, the RBC volume was significantly lower in the POTS group than that in the non-POTS group (78% vs. 85% of the expected volume, p = 0.013). The orthostatic decrease of MCA flow velocity was 28.3% in the POTS group and 32.5% in the non-POTS group (p = 0.140). The orthostatic pulsatility index increment was 15.4% in the POTS group and 20.5% in the non-POTS group (p = 0.438). Moreover, basic demography and hemoglobin levels were not different between the two groups. After multivariate linear regression (dependent variables including age, sex, body surface, and groups), only the presence of POTS significantly predicted the RBC volume (p = 0.006).ConclusionThe results of our study indicated that low RBC volume may play an important role in the pathophysiology of OI in this group of patients. Moreover, its role seems even more relevant in patients with POTS than in those without. Further studies for mechanistic evaluation are needed in the future.     

Non-adherence to statin therapy: a major challenge for preventive cardiology

Background: Hypercholesterolemia is a major risk factor for atherosclerosis and cardiovascular disease, the leading cause of death worldwide. In the last twenty years, effective lipid-lowering therapies, particularly statins, have become widely available to prevent and reverse the progression of disease. However, there is a significant gap between expected and actual benefits; this may be attributed to poor adherence to statin therapy. Objective: To define the extent, causes (including psychological aspects), consequences and management of non-adherence to statins. Methods: Literature using PubMed and Medline up to and including 30 July 2009. Results: Adherence to statin therapy is suboptimal in both primary and secondary prevention of cardiovascular disease. Causes vary, and include patient factors (e.g., comorbidities, financial constraints, psychological issues), practitioner factors (e.g., poor knowledge of adherence, time constraints, poor communication skills and patient–doctor working alliance) and system factors (e.g., medication costs, lack of clinical monitoring, drug side effects). Non-adherence is associated with adverse health outcomes and increased costs of healthcare. A framework, based on a multidisciplinary approach, for addressing non-adherence, including managing the statin-intolerant patient, is presented. Conclusions: Non-adherence to statins is a significant issue for the prevention and treatment of cardiovascular disease. Increased awareness of the causes and solutions for overcoming non-adherence, including safer prescribing, improvement in physician–patient alliance and reduction in drug costs, will enhance the cost-effectiveness of the use of statins and significantly improve patient care and outcomes.     

Everyday Experiences of Women Posttreatment After Breast Cancer: The Role of Uncertainty,Hassles, Uplifts,and Coping on Depressive Symptoms

Considerable research has examined the experiences of women at risk, during diagnosis, and throughout treatment of breast cancer; however, less in known about these women posttreatment. Many women report dealing with extensive long-standing ailments such as lymphedema and fatigue, as well as a fear of illness recurrence. However, women posttreatment also report finding benefit and meaning from their cancer occurrence. These orthogonal outcomes may be related to the uncertainty an individual is able to tolerate. Thus, this online study examined Canadian women who completed treatment for breast cancer (n = 42), and women in a control condition (n = 42), responses to the daily experience of hassles and uplifts, intolerance of uncertainty, coping strategies, and depressive symptoms. Although depressive symptoms and daily hassles did not differ between the two groups of women, women with a previous cancer experience reported a greater amount and frequency of daily uplifts, and hassle intensity predicted fewer depressive symptoms among women posttreatment compared to healthy controls. Furthermore, hassle intensity mediated the relationship between intolerance of uncertainty and depressive symptoms, but only for women in the control condition. Last, for women posttreatment only, the use of emotion-focused coping to deal with a fear of cancer recurrence mediated the relationship between intolerance of uncertainty and depressive symptoms, whereas problem-focused, avoidant, or cognitive-restructuring coping strategies did not. These results point to the need to provide resources to women posttreatment, but also that those women who survive breast cancer can obtain benefits from the experience.     

血清生长激素释放肽水平与早产儿喂养不耐受相关性研究

目的测定早产儿生后24 h内血清生长激素释放肽(Ghrelin)水平,探讨其与早产儿喂养不耐受的相关性。方法选取2012年5月至2012年10月生后24 h内入住安徽医科大学第一附属医院新生儿科无伴发疾病的早产儿52例(年龄<24 h)作为研究对象,采用ELISA法测定生后24 h内的血清Ghrelin水平,同时记录其喂养情况,根据是否发生喂养不耐受分为喂养不耐受组(24例)与无喂养不耐受组(28例)两组,比较两组血清Ghrelin水平。结果喂养不耐受组生后24h内血清Ghrelin水平明显低于无喂养不耐受组,差异有统计学意义[(604.79±28.07)pg/ml vs(650.75±34.34)pg/ml,P<0.05]。结论血清Ghrelin水平与早产儿喂养不耐受发生有关,早期检测血清Ghrelin水平对预测早产儿喂养不耐受有一定价值;外源性Ghrelin可能具有改善早产儿肠内喂养耐受性的作用。     

Ingested Mineral Fibers

Three different laboratories independently investigated the ability of ingested mineral fibers to penetrate tissues in rats. All concluded that there was no evidence of tissue penetration by ingested mineral fibers.

These experimental observations are supported by the findings in coal and hard-rock miners who swallow, during their lifetime, nearly 100 times the amount of dust that is stored in their lungs. The intestinal wall or mesenteric lymph nodes of these people show no evidence of storage of the ingested dust particles. Animals fed asbestos over much of their lifetime and allowed to live to the age of cancer production, failed to provide evidence of a cancerogenic effect.     

High-resolution melting analysis using unlabeled probe and amplicon scanning simultaneously detects several lactase persistence variants

Abstract

Lactase persistence and thereby tolerance to lactose is a common trait in people of Northern European descent. It is linked to the LCT ?13910C>T variant located in intron 13 of the MCM6 gene 13.9 kb upstream of the lactase (LCT) gene. In people of African and Middle Eastern descent, lactase persistence can be associated with other variants nearby the ?13910C>T variant, limiting the use of the ?13910C>T-based SNP analysis, e.g. TaqMan assays for the diagnosis of lactose intolerance. Using high-resolution melting analysis, we identified five samples that were heterozygous for the ?13915T>G variant among 78 patients genotyped as ?13910C/C by a TaqMan assay. All samples originated from patients of probable Middle Eastern descent. In order to detect the ?13910 and ?13915 variants simultaneously, we developed a new high-resolution melting (HRM) analysis assay based on unlabeled probe genotyping and simultaneous amplicon scanning analysis. By using this assay we were able to distinguish the ?13910 and ?13915 genotypes clearly. Furthermore, we identified two rare variants, the ?13907C>G and ?13913T>C. With this method, based on an inexpensive unlabeled probe, it is possible to simultaneously detect the ?13910C>T and ?13915T>G variants in addition to rarer variants surrounding the ?13910 site. This new method may contribute to improve the diagnostic performance of the genetic analysis for lactose intolerance.