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21.
In healthcare practice, the sedimentation rate of red blood cells (erythrocytes) is a widely used clinical parameter for screening of several ailments such as stroke, infectious diseases, and malignancy. In a traditional pathological setting, the total time taken for evaluating this parameter varies typically from 1 to 2 h. Furthermore, the volume of human blood to be drawn for each test, following a gold standard laboratory technique (alternatively known as the Westergren method), varies from 4 to 5 ml. Circumventing the above constraints, here we propose a rapid (∼1 min) and highly energy efficient method for the simultaneous determination of hematocrit and erythrocyte sedimentation rate (ESR) on a microfluidic chip, deploying electrically driven spreading of a tiny drop of blood sample (∼8 μl). Our unique approach estimates these parameters by correlating the same with the time taken by the droplet to spread over a given radius, reproducing the results from more elaborate laboratory settings to a satisfactory extent. Our novel methodology is equally applicable for determining higher ranges of ESR such as high concentration of bilirubin and samples corresponding to patients with anemia and patients with some severe inflammation. Furthermore, the minimal fabrication steps involved in the process, along with the rapidity and inexpensiveness of the test, render the suitability of the strategy in extreme point-of-care settings. 相似文献
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Cynthia R. Chambers Michael L. Wehmeyer Yumiko Saito Kerry M. Lida Youngsun Lee Vandana Singh 《Exceptionality》2013,21(1):3-15
Abstract Promoting self-determination has become an important aspect of the educational programs of students with disabilities. There is now a sufficient literature base to support some syntheses that enable researchers to judge their progress in this area to date and to provide direction for future research and practice. For this study, we conducted a literature review of studies that measured or examined global self-determination. 相似文献
24.
Suparna Dhara Anindya Dasgupta Jayanta Kumar Rout Ushasi Banerjee Sayantan Dasgupta Arindam Ghosh 《Indian journal of clinical biochemistry : IJCB》2015,30(1):99-103
Psoriasis is a chronic inflammatory disease associated with an increased insulin resistance, obesity and cardiovascular risk. The present study was aimed to assess insulin resistance and pattern of body fat deposition in psoriasis. Body mass index (BMI) and waist circumference (WC) were measured in 40 psoriatic patients and 46 age- and sex-matched control subjects. Fasting blood glucose (FBG) and serum insulin level were measured by standard photometric method and ELISA respectively. HOMA-IR (homeostatic model of insulin resistance) was calculated by appropriate software. The results indicated that case and control groups were comparable in terms of age and sex (p = 0.934) with an increased prevalence of psoriasis among male subjects (60 %). FBG and mean WC between the two groups were statistically not significant (p value = 0.271 and 0.21 respectively). BMI was significantly higher in case group compared to the control group (p = 0.049). Serum insulin level and insulin resistance in the psoriatic patients were significantly higher (p value <0.001). Multiple regression analysis revealed that insulin resistance (measured by HOMA) was dependent on BMI and WC at a significance level of p < 0.001 and 0.043 respectively. Therefore, the psoriatic patients in this region have significantly high amount of fasting serum insulin level along with an increased IR though their FBG level remains normal. Furthermore, these abnormalities are significantly dependent on total body fat as well as abdominal fat deposits. We suggest that psoriatic patients need to be evaluated for metabolic syndrome and managed accordingly. 相似文献
25.
R. Dhananjayan T. Malati Y. Rupasree Vijay Kumar Kutala 《Indian journal of clinical biochemistry : IJCB》2015,30(3):263-270
The present work was aimed to study the association of one carbon genetic variants, hyperhomocysteinemia and oxidative stress markers, i.e., serum nitrite, plasma malondialdehyde (MDA) and glutathione (GSH) on intimal medial thickening (IMT) in patients with type 2 diabetes mellitus (T2D). A total number of 76 subjects from ACS Medical College and Hospital, Chennai, India were included in the study, i.e., Group I (n = 42) of T2D and Group II (n = 34) of age- and sex matched healthy controls. The glycated haemoglobin was measured by ion-exchange resin method; plasma homocysteine by Enzyme Linked Immunosorbant Assay method; serum nitrite (nitric oxide, NO), plasma MDA and GSH by spectrophotometric methods; the IMT by high frequency ultrasound. The polymorphisms of one carbon genetic variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism and amplified fragment length polymorphism methods. Results indicate that methyltetrahydrofolate homocysteine methyl transferase (MTR) A2756G allele was found to be protective in T2D and the other variants were not significantly associated with T2D. Glutamate carboxypeptidase II (GCP II) C1561T (r = 0.34; p = 0.05) and methylene tetrahydrofolate reductase (MTHFR) C677T (r = 0.35; 0.04) showed positive correlation with plasma homocysteine in T2D cases. In this study, MTR A2756G allele was found to be protective in T2D; GCP II C1561T and MTHFR C677T showed positive association with plasma homocysteine in T2D cases. Among all the genetic variants, MTR A2756G was found influence IMT. RFC 1 G80A and TYMS 5′-UTR 2R3R showed synergistically interact with MTR A2756G in influencing increase in IMT. 相似文献
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Ranbir Singh Malik 《Asia Pacific Journal of Education》2015,35(1):27-39
Evidence from Australia lends support to the “Asian high achieving syndrome” in Chinese-Australian students and “self-deprivation syndrome” in Anglo-Australian students. Applying ethnographic case studies approach for doctoral thesis the author collected data on a longitudinal basis from homes and school of these students. All of these students attended the same school located in a predominantly middle class suburb of Perth Metropolitan area in Western Australia. Chinese-Australian families had settled in Perth from Malaysia, Singapore and Hong Kong, whereas Anglo-Australian families had been residing in Perth for three generations. Impetus to revisit these students (now young adults with their own families) 10 years later came from an urge to test the validity of the prediction the author had made in the concluding chapter of his doctoral thesis. The author had claimed that “if Anglo-Australian parents keep on dwelling in the era of 1950s and 1960s and do not change their laid-back attitude about education, their children could eventually be under-privileged in their own country”. Ten years later, the author undertook a follow-up study on these young adults from six of the eight original families in order to find out their occupational destinations and future aspirations. Data for the follow-up study were collected from these young adults and their parents. These research cases were interviewed twice, each time approximately for two hours and their parents were interviewed once for two to three hours. The purpose of this paper is to report the findings of the follow-up study which reveals a remarkable relationship between the attitude towards schooling and academic performance with their subsequent occupational destination. 相似文献
28.
What should children and young adolescents read? Recent changes in the English curriculum have once again shifted the focus towards more canonical texts, but does featuring such texts on the course necessarily equate to rigorous teaching and in-depth learning? Through a self-examination of her own reading history, the author argues for a dialogic approach to reading and text selection instead, so that students may negotiate better understandings of themselves and their own socio-cultural contexts. 相似文献
29.
Gururao Hariprasad Divya Kota Sundararajan Baskar Singh Alagiri Srinivasan Souparno Adhikary 《Indian journal of clinical biochemistry : IJCB》2014,29(4):430-441
Clonorchis sinensis or the Chinese liver fluke is one of the most prevalent parasites affecting a major population in the oriental countries. The parasite lacks lipid generating mechanisms but is exposed to fatty acid rich bile in the liver. A secretory phospholipase A2, an enzyme that breaks down complex lipids, is important for the growth of the parasite. The enzyme is also implicated in the pathogenesis leading up to the hepatic fibrosis and its complications including cancer. The five isoforms of this particular enzyme from the parasite therefore qualify as potential drug targets. In this study, a detailed structural and ligand binding analysis of the isoforms has been done by modeling. The overall three dimensional structures of the isoforms are well conserved with three helices and a β-wing stabilized by four disulfide bonds. There are characteristic differences at the calcium binding loop, hydrophobic channel and the C-terminal domain that can potentially be exploited for drug binding. But the most significant feature pertains to the catalytic site where the isoforms exhibit three variations of either a histidine-aspartate-tyrosine or histidine-glutamate-tyrosine or histidine-aspartate-phenylalanine. Molecular docking studies show that isoform specific residues and their conformations in the substrate binding hydrophobic channel make unique interactions with certain inhibitor molecules resulting in a perfect tight fit. The proposed ligand molecules have a predicted affinity in micro-molar to nano-molar range. Interestingly, few of the ligand binding interaction patterns is in accordance to the phylogenetic studies to thereby establish the usefulness of evolutionary mechanisms in aiding ligand design. The molecular diversity of the parasitic PLA2 described in this study provides a platform for personalized medicine in the therapeutics of clonorchiasis.
Electronic supplementary material
The online version of this article (doi:10.1007/s12291-013-0377-1) contains supplementary material, which is available to authorized users. 相似文献30.
Droplet-based microfluidics has gained extensive research interest as it overcomes several challenges confronted by conventional single-phase microfluidics. The mixing performance inside droplets/slugs is critical in many applications such as advanced material syntheses and in situ kinetic measurements. In order to understand the effects of operating conditions on the mixing performance inside liquid slugs generated by a microfluidic T-junction, we have adopted the volume of fluid method coupled with the species transport model to study and quantify the mixing efficiencies inside slugs. Our simulation results demonstrate that an efficient mixing process is achieved by the intimate collaboration of the twirling effect and the recirculating flow. Only if the reagents are distributed transversely by the twirling effect, the recirculating flow can bring in convection mechanism thus facilitating mixing. By comparing the mixing performance inside slugs at various operating conditions, we find that slug size plays the key role in influencing the mixing performance as it determines the amount of fluid to be distributed by the twirling effect. For the cases where short slugs are generated, the mixing process is governed by the fast convection mechanism because the twirling effect can distribute the fluid to the flow path of the recirculating flow effectively. For cases with long slugs, the mixing process is dominated by the slow diffusion mechanism since the twirling effect is insufficient to distribute the large amount of fluid. In addition, our results show that increasing the operating velocity has limited effects on improving the mixing performance. This study provides the insight of the mixing process and may benefit the design and operations of droplet-based microfluidics. 相似文献