Polymorphonuclear leukocytic sialic acid and sialidase activity in obesity

The level of sialic acid in the obese polymorphonuclear leukocytes (PMNL) was found to be significantly reduced as compared to normal. Activity of sialic acid degrading enzyme, sialidase, was found to be increased in the obese state. Restoration in both sialic acid content and sialidase activity was also evidenced in the PMNL of treated obese patients.     

注意:概念、测验和教师等级评定

本文的理论部分探讨注意的性质、注意的测验和测量，以及注意缺陷的鉴定。注意具有选择性，它包含着对冲动反应的抑制和对分心的克服。第二部分讨论三项经验研究，这些研究探索了注意等级评定量表的使用，该量表由教师对儿童在课堂情境下的注意情况进行等级评定。研究发现，教师的等级评定可以预测课外情境中儿童在注意测验上的表现。这些等级评定具有显著的预测性，正如该测验的结果所表明的，教师一直关注着儿童注意的一个重要方面，即对分心的抵制。在结论性评述中，讨论了可能导向注意缺陷改善的动态测试。第三部分是附录部分，例举了若干注意力测验。     

Groundwater scarcity impact on inclusiveness and women empowerment: Insights from school absenteeism of female students in two watersheds in India

A survey was conducted in eight secondary schools located in two watersheds in Gujarat and Rajasthan (semi-arid region of India) to assess students’ perceptions about groundwater scarcity issues and the impact of the scarcity on their educational opportunities. Survey responses to a detailed questionnaire by a cohort of students in both watersheds; school attendance records of year 8 class students (13–14 years old) and responses gathered via a socio-economic survey involving 500 families in the study area were used in the study. In both watersheds, >90% students identified groundwater scarcity as a major issue. Required to work at home or farm, about 65% students in Gujarat and 60% in Rajasthan missed school for up to 2 days/month; and a smaller proportion (～ 30%) missed schools for 4 or more days/month. School absenteeism was found to be linked with gender; female students missed schools more frequently than their male counterpart. The school attendance records in Rajasthan showed that the frequency of female students missing schools for 5 or more days/month was on an average 2–10 times greater than that for males. The gender difference in absenteeism in all schools was statistically significant (P?<?.018**). The study highlighted that groundwater scarcity in the study area, and consequent demand on their time for household work including fetching drinking water are contributing factors towards limiting their educational and economic opportunities. Groundwater scarcity can be one of the key factors that can limit inclusiveness and empowerment of women and need to be considered in policy-making.     

Plate Tectonics and Europa’s Icy Shell

A unique attribute of Earth is the presence of plate tectonics. Not only does it give rise to continents, mountain chains, and ocean basins but also promotes a high level of biodiversity. It is the reason for the formation of the so-called ‘Pacific Ring of Fire’ – a belt of intense volcanic activity and a large number of earthquakes surrounding the Pacific ocean. But what drives the plate motion? Did Earth always have plate tectonics? These are some fascinating geoscientific questions. In trying to answer these questions, an effort is made to impress upon the reader the vast ocean of uncertainty, and hence the opportunity, in the field of Earth and Planetary Sciences. To make it more engaging, the article provides a peek into the long process which culminated in the present-day theory of plate tectonics on Earth. While the first half of the article focuses on subduction and its cause, the second half summarizes a recent finding made on the surface of Europa. In view of readability across disciplines, the complex subject details are kept to bare minimum.     

Role of Homocysteine in Cognitive Impairement and Alzheimer’s Disease

A high circulating concentration of the non proteinogenic amino acid homocysteine has been implicated as a risk factor for Alzheimer’s Disease and its prodromal stage, mild cognitive impairement. Furthermore, hyperhomocysteinaemia has been directly attributed to a deficiency in vitamins B12, folate, and B6. Several studies have demonstrated decrease in progression of mild cognitive impairement to Alzheimer’s Disease, and some have even shown an improvement in cognition after vitamin supplements with B12 and folate. Plausible mechanisms linking hyperhomocysteinaemia to Alzheimer’s and cognitive impairement have been hypothesized and demonstrated in hyperhomocysteinemic mice models. However, some studies have not elucidated any benefit of vitamin supplements in subjects with cognitive impairment. Hence, multicentric clinical studies need to be conducted to substantiate the mechanisms of neuronal degeneration due to hyperhomocysteinaemia and to demonstrate the beneficial effect of folate, B6 and B12 supplements on cognition.     

Toxic effects of Litsea elliptica Blume essential oil on red blood cells of Sprague-Dawley rats

Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, che-mopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinoeyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.     

Epigallocatechin-3-gallate affects the growth of LNCaP cells via membrane fluidity and distribution of cellular zinc

Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:l was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane,decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG.     

Perspective: Flicking with flow: Can microfluidics revolutionize the cancer research?

According to the World Health Organization, cancer is one of the leading causes of death worldwide. Cancer research, in its all facets, is truly interdisciplinary in nature, cutting across the fields of fundamental and applied sciences, as well as biomedical engineering. In recent years, microfluidics has been applied successfully in cancer research. There remain, however, many elusive features of this disease, where microfluidic systems could throw new lights. In addition, some inherent features of microfluidic systems remain unexploited in cancer research. In this article, we first briefly review the advancement of microfluidics in cancer biology. We then describe the biophysical aspects of cancer and outline how microfluidic system could be useful in developing a deeper understanding on the underlying mechanisms. We next illustrate the effects of the confined environment of microchannel on cellular dynamics and argue that the tissue microconfinement could be a crucial facet in tumor development. Lastly, we attempt to highlight some of the most important problems in cancer biology, to inspire next level of microfluidic applications in cancer research.     

Association of CETP and LIPC Gene Polymorphisms with HDL and LDL Sub-fraction Levels in a Group of Indian Subjects: A Cross-Sectional Study

There is an increasing interest to understand the molecular basis of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) subfractions and their association with coronary artery disease (CAD). The formation of these subfractions is greatly influenced by hepatic lipase (HL) and cholesteryl ester transfer protein (CETP) enzymes. To identify genetic markers influencing LDL and HDL subfractions and their role in CAD we performed a case–control genetic association study on 117 healthy controls and 119 angiographically verified CAD patients. Biochemical analysis was performed using standard assays. HDL-C and LDL-C subfractions were estimated using precipitation methods. Genotyping of C-514T (rs1800588) in the LIPC gene for HL and I405V (rs5882) in the CETP gene was done using PCR-based restriction enzyme analysis and sequencing. Both the polymorphisms were not associated with CAD. The C-514T was associated with increased HDL₃-C levels in controls (P = 0.049). The I405V polymorphism was found to be associated with low levels of small dense, LDL (P = 0.038). A multiple regression analysis showed that the effects were dependent on gender and triglyceride levels. We conclude that these polymorphisms are not associated with CAD but are important determinants of HDL-C and small dense LDL particles in our population.