Mediator-free total cholesterol estimation using a bi-enzyme functionalized nanostructured gold electrode

We report the fabrication of a bi-enzyme functionalized nanostructured Au electrode for the mediator-free determination of total cholesterol. A one-step electrochemical route for the synthesis, functionalization and deposition of Au nanostructures via the electroreduction of gold chloride onto indium tin oxide (ITO) coated glass plates has been proposed. The covalent biofunctionalization of the optimized Au electrode was done with cholesterol esterase (ChEt) and cholesterol oxidase (ChOx) to investigate the kinetic parameters and the sensing characteristics. The ChEt-ChOx/Glu-NanoAu/ITO bioelectrode has a surface-controlled electrode reaction with an electron transfer coefficient and a charge transfer rate constant of 0.68 and 7.09 s(-1), respectively. Under the optimal conditions, the bioelectrode undergoes a direct electron transfer reaction and exhibits a high sensitivity of 0.53 mA mM(-1) cm(-2) and a low detection limit of 1.57 mu M for cholesterol ester without the use of any redox mediator. In addition, the kinetic analysis reveals that the bioelectrode exhibits a surface concentration of 8.82 x 10(-12) mol cm(-2). The sensor has also been validated with clinical samples. The proposed biosensor shows good sensitivity, stability and selectivity towards total cholesterol and may thus find implications in the fabrication of biosensing devices

Real-time sensing of static displacement and vibrations using HOM interference based quantum sensor

Hong-Ou-Mandel (HOM) interference, bunching of two indistinguishable photons on a balanced beam-splitter, has emerged as a promising tool for quantum sensing. The interference dip-width, thus the spectral-bandwidth of interfering pair-photons, highly influences the resolution of HOM-based sensors. Typically, the pair-photons bandwidth, generated through parametric down-conversion, is increased using bulky and expensive ultrafast lasers, limiting their use outside the lab. Here we show the generation of pair-photons with flexible spectral-bandwidth even using single-frequency, continuous-wave diode laser enabling high-precision, real-time sensing. Using 1-mm-long periodically-poled KTP crystal, we produced degenerate, high-brightness, paired-photons with spectral-bandwidth of 163.42$\pm$1.68 nm resulting in a HOM-dip width of 4.01$\pm$0.04 $\mu$m to measure a displacement of 60 nm, and vibration amplitude of $205\pm0.75$ nm with increment (resolution) of $\sim$80 nm, and frequency of 8 Hz. Deployment of Fisher-information and maximum likelihood estimator enables optical delay measurement as small as 4.97 nm with precision (Cram\'er-Rao bound) and accuracy of 0.89 and 0.54 nm, respectively. The 17$\times$ enhancement of Fisher-information for the use of 1 mm crystal over 30 mm empowers the HOM-based sensor achieving any arbitrary precision (say $\sim$5 nm) in small number of iterations ($\sim$3300) and time (19 minutes); establishing it's capability for real-time, precision-augmented, in-field quantum sensing applications

Effect of Ionic Strength on Porphyrin Drugs Interaction with Quadruplex DNA Formed by the Promoter Region of C-myc and Bcl2 Oncogenes

C-myc and Bcl2 are well characterized oncogenes that are capable of forming G-quadruplex structures. Promoter regions of C-myc and Bcl2 forming G-quadruplex structures are chemically synthesized and G-quadruplex structure is formed in presence of 100 mM potassium ion. Three different porphyrin drugs, namely TMPyP2, TMPyP3, and TMPyP4 are allowed to interact with quadruplex DNA complex and the site and nature of interaction are studied. Drug interactions with quadruplex DNA were carried out in different potassium ionic strengths using fluorescence spectroscopy. It is found that fluorescence hypochromicity decreases with an increase in ionic strength in the case of TMPyP4, TMPyP3, and TMPyP2. Fluorescence titration studies and Job plots indicate that four molecules of TMPyP4, two molecules of TMPyP3 and TMPyP2 are interacting with one molecule of quadruplex DNA

Assessment of pulmonary function in patients with type 2 diabetes mellitus: a case-control study

Background:As other microvascular complications, respiratory involvement is far less studied among patients with type-2 Diabetes Mellitus (DM). Objective: to study the extent of pulmonary function limitation among patients with type-2 DM.  Methods:Hospital based matched case-control study.Results:Total of 90 cases and 90 controls matched for age, sex, height and weight were recruited. Patients with DM had neuropathy [63.3% (57; male=27: Female: 30)], retinopathy [44.4% (40; male=22: Female: 18)], nephropathy [41.1% (37; male=17: Female: 20)] and microalbuminuria [14.4% (13; male=5: Female: 8)]. All cases and 88 controls observed with FEV1:FVC ratio of >70.0%, further assessment for delineation of normal and restrictive pattern patients with high level of predicted values of FEV1 as compare to FVC showed that significantly (P = 0.00) more (Cases: 76.6%; Controls: 42.2%) cases had FEV1 >FVC predicted levels as compare to controls, means among diabetics odds of restrictive pattern of lung abnormality is four times (OR: 4.4; CI: 2.3-8.5) more as compare to non-diabetics. In addition a long duration of DM was significantly (r: 0.39; P = 0.00) positively correlated with lung dysfunction.  Conclusion: Patients with type 2 DM patients as compare to its controls observed with restrictive pattern of lung dysfunction.

Real Time Water Quality Monitoring and Flow Diverting System

Nowadays, almost every person on earth is facing trouble because of growing population, aging infrastructure and pollution. There are several types of pollution namely: Soil, Land, Water, Air etc. Water is a very precious resource for all living beings and its pollution is a grave concern for the society. One major reason for water pollution is industrial waste. The indiscriminate discharge of these wastewater streams into the environment pollutes the receiving bodies. The traditional method to challenge pH, turbidity and other parameters is to collect samples manually and then send them to laboratory for quality check. However, it has been unable to achieve water quality examining. The proposed system consists of model based on IoT platform and uses temperature, pH and turbidity sensors to check the water quality. Water quality is monitored and data from the sensors are sent to the web server at regular interval of time under RaspberryPi-3 using internet. The proposed system is free from any external or human interference and it can be used for water bodies like rivers and ponds

Assessment of the Self-Perception of Dental Appearance, Its Comparison with Orthodontist's Assessment and Demand for Treatment in Eastern Nepalese Patients

Aims. The aim of this study was to assess the self-perception of dental appearance among Eastern Nepalese patients using aesthetic component (AC) of the index of orthodontic treatment need (IOTN) and to compare it with that of an orthodontist's assessment using the same scale and determine whether gender, area of residence, and level of education influence subject's self-perception and orthodontist's ratings. Methods. A total of 252 subjects (equal number of male and female) were conveniently selected. The average ages of subjects were 22.33 ± 2.114 years. The level of subject's perception and orthodontist's assessment was analyzed by nonparametric Chi square test. Kappa coefficient was done to verify its agreement. The Spearman's correlation test was used to check the association of educational level and age. Mann-Whitney test was used to check the associations of sex and areas of residence. Results. The demand for treatment was significantly associated with the perception of the subject and orthodontist's assessment. However, age, gender, and educational level were statistically insignificant in influencing subject perception and orthodontist's assessment. Conclusion. Patient's self-perception should be given equal importance while planning orthodontic treatment

Prevalence Of Tuberculin Skin Test Positivity In Patients Of Early Rheumatoid Arthritis- Study from a tertiary care centre in North India.

Objective: To assess the prevalence of tuberculin skin test (TST) positivity in early rheumatoid arthritis patients (< 6months disease duration) using Tuberculin sensitivity testing in a TB endemic country. Method: Included in this cross-sectional study were 200 patients of early rheumatoid arthritis divided into three groups- treatment naïve, patients on methotrexate only and methotrexate plus low dose corticosteroids. Results: 200 early RA patients and 60 healthy controls were included in this study. The median age of the study population was 43 years (IQR 33-51) with a mean disease duration of 3.4 ± 2.1 months. 54 patients (27%) with early RA and 22 healthy control (36.7%) had TST positive (p=0.1). Conclusion: Tuberculin positivity is low among patients with early RA as compared to the general population. The use of low dose steroids or methotrexate doesn’t affect the tuberculin anergy

Expression Of Mir-34a In T-cells Infected By Human T-lymphotropic Virus 1

Human T-lymphotropic virus 1 (HTLV-1) immortalizes T-cells and is the causative agent of adult T-cell leukemia/lymphoma (ATLL). HTLV-1 replication and transformation are governed by multiple interactions between viral regulatory proteins and host cell factors that remain to be fully elucidated. The present study investigated the impact of HTLV-1 infection on the expression of miR-34a, a microRNA whose expression is downregulated in many types of cancer. Results of RT-PCR assays showed that five out of six HTLV-1-positive cell lines expressed higher levels of miR-34a compared to normal PBMC or purified CD4+ T-cells. ATLL cell line ED, which did not express miR-34a, showed methylation of the miR-34a promoter. Newly infected PBMC and samples from 10 ATLL patients also showed a prominent increase in miR-34a expression compared to PBMC controls. The primary miR-34a transcript expressed in infected cell line C91PL contained binding motifs for NF-kappa B and p53. Pharmacological inhibition of NF-kappa B with Bay 11-7082 indicated that this pathway contributes to sustain miR-34a levels in infected cells. Treatment of infected cell lines with the p53 activator nutlin-3a resulted in a further increase in miR-34a levels, thus confirming it as a transcriptional target of p53. Nutlin-3a-treated cells showed downregulation of known miR-34a targets including the deacetylase SIRT1, which was accompanied by increased acetylation of p53, a substrate of SIRT1. Transfection of C91PL cells with a miR-34a mimic also led to downregulation of mRNA targets including SIRT1 as well as the pro-apoptotic factor BAX. Unlike nutlin-3a, the miR-34a mimic did not cause cell cycle arrest or reduce cell viability. On the other hand, sequestration of miR-34a with a sponge construct resulted in an increase in death of C91PL cells. These findings provide evidence for a functional role for miR-34a in fine-tuning the expression of target genes that influence the turnover of HTLV-1-infected cells