Sub 20 nm Short Channel Carbon Nanotube Transistors

Carbon nanotube field-effect transistors with sub 20 nm long channels and on/off current ratios of > 1000000 are demonstrated. Individual single-walled carbon nanotubes with diameters ranging from 0.7 nm to 1.1 nm grown from structured catalytic islands using chemical vapor deposition at 700 degree Celsius form the channels. Electron beam lithography and a combination of HSQ, calix[6]arene and PMMA e-beam resists were used to structure the short channels and source and drain regions. The nanotube transistors display on-currents in excess of 15 microA for drain-source biases of only 0.4 Volt.Comment: Nano Letters in pres

Self care activities among patients with diabetes attending a tertiary care hospital in Mangalore Karnataka, India

Background: Increasing prevalence of diabetes in India is resulting in an epidemiological transition. The care of the people with diabetes is traditionally seen as doctor centered, but the concept of self‑care of people with diabetes is a new domain and is proven beneficial. Aim: The aim was to determine the practice of self‑care activities among people with diabetes attending a tertiary care hospital in Mangalore. Subjects and Methods: A facility‑based cross‑sectional study was conducted in Government Wenlock Hospital, Mangalore during September–October 2012. A total of 290 patients with >1‑year duration of diabetes mellitus (DM) were asked to respond to summary diabetes self‑care activities questionnaire after obtaining the consent from them. The statistical analysis was performed in terms of descriptive statistics and association between the variables was tested using Mann–Whitney U‑test. Results: A healthy eating plan on a daily basis was followed by 45.9% (133/290) of the participants, daily exercises for 30 min were followed by 43.4% (126/290), and regular blood sugar monitoring was done by 76.6% (222/290). Regarding the adherence to oral hypoglycemic agents and insulin, daily adherence to medication was seen among 60.5% (155/256) and 66.9% (138/206) were found to be adherent to insulin injections on a daily basis. Conclusions: Self‑care practices were found to be unsatisfactory in almost all aspects except for blood sugar monitoring and treatment adherence. As these practices are essential for prevention of complications and better quality‑of ‑life, more efforts should be put to educate the people with diabetes.Keywords: Cross‑sectional studies, Diabetes mellitus, India, Self‑car

CHRONIC ORAL TOXICITY STUDIES OF CRUDE ETHANOLIC EXTRACT AND ETHANOLIC FRACTION OF PELLIONIA HEYNEANA WEDD. LEAF IN WISTAR RATS

Objective: Pellionia heyneana Wedd. leaf has been used by the Cholanaikan tribe as a traditional medicine to enhance immunity and also to treat various liver ailments. However, no scientific reports are available regarding its long term toxicity studies. The objective of the present study was to investigate the chronic oral toxicity study of P. heyneana leaf.Methods: In the present study, scientific evaluation of oral toxicity of P. heyneana crude ethanolic leaf extract (PHLE) and leaf ethanolic fraction (PHEF) were carried out in Wistar rats. Animals were fed with three varying concentrations (500 mg/kg, 1000 mg/kg and 1500 mg/kg) of PHLE and PHEF for 90 d. During the study period, all the animals were closely observed for any morbidity or mortality, food and water intake, body weight etc. The effect of PHLE and PHEF on animal behaviour, metabolism, liver function, kidney function, blood glucose level, in vivo antioxidant status, haematological parameters, histopathology of internal organs etc. were evaluated after 90 d chronic toxicity study.Results: All the animals administered with PHLE/PHEF up to 1500 mg/kg dose did not show any deleterious changes in normal metabolism, histopathology of internal organs, haematological and biochemical indices.Conclusion: All these results revealed that PHLE and PHEF of P. heyneana are non toxic in long term oral administration in Wistar rats.Â

Ameliorative effect of ethanolic extract of roots of Tetracera akara (Burm. f.) Merr. on D-galactosamine induced hepatotoxicity in Wistar rats by downregulation of inflammatory mediators like TNFα, COX-2 and iNOS

161-171Tetracera akara, a climbing shrub locally called Nennalvalli or Pattuvalli, is an ethnomedicinal plant used by Kani tribe of Kerala to treat chronic liver disorders and inflammatory conditions.  The present study was aimed to evaluate the hepatoprotective activity of ethanolic extract of roots of Tetracera akara root on D-Galactosamine induced hepatotoxicity in Wistar rats. Hepatotoxicity was induced in Wistar rats by intraperitoneal injection of D-GalN (400 mg/kg in saline) in Wistar rats. Ethanolic extract of T. akara root (TA ETH) was administered to the experimental rats in varying doses of (50, 150 and 300 mg/kg/day), p. o. for 7 days. The hepatoprotective effect was evaluated by the estimation of biochemical markers of hepatic injury, anti-oxidant status of the liver by estimating hepatic catalase, superoxide dismutase, glutathione and malondialdehyde, gene and protein expression level of inflammatory marker genes and histopathological evaluation of experimental animals. Administration of TA ETH (150 and 300 mg/kg) significantly (P ≤0.05) restored the levels of serum bilirubin, protein and other hepatic enzymes almost comparable to the standard drug Silymarin-treated groups. The levels of antioxidant enzymes like SOD and CAT were elevated and lipid peroxidation was inhibited as evident from the reduced levels of MDA. The gene expression studies by quantitative PCR method showed that TA ETH significantly (P ≤0.05) downregulated pro inflammatory cytokines, inflammatory COX-2 genes and upregulated IL 10 gene levels in D-GalN induced liver tissue, which was further confirmed in protein estimation by ELISA method. The histopathological observations were in correlation with the biochemical findings showing the presence of normal hepatic architecture, which further evidenced the hepatoprotective effect of TA ETH. Ethanolic extract of the root of T. akara possesses significant hepatoprotective activity mainly by scavenging reactive free radicals, boosting the endogenous antioxidant system in liver and inhibiting pro-inflammatory mediator like TNF α, COX-2, iNOS and promoting the anti-inflammatory IL 10, thus substantiating the tribal claim

ANTI-INFLAMMATORY AND ANALGESIC ACTIVITY OF ARENGA WIGHTII GRIFF.-AN ENDEMIC PALM OF WESTERN GHATS

Objective: The present study aims to scientifically validate the anti-inflammatory and analgesic activities of Arenga wightii.Methods: The stem pith was excised from mature palm, sliced into small pieces, shade dried and powdered. The powder was extracted with ethanol, concentrated under reduced pressure and the crude extract was referred to as AW. The anti-inflammatory and analgesic activity of AW was analyzed in Wistar rats and Swiss albino mice.Results: The results revealed that the ethanolic extract of the stem pith of A. wightii showed a dose dependent anti-inflammatory and analgesic activity, which was comparable to the standards, indomethacin and acetyl salicylic acid respectively.Conclusion: The results of the current study reveal that A. wightii possesses significant anti-inflammatory and analgesic activity.Â

The Pharmacokinetics of ofloxacin, rifampicin, isoniazid and pyrazinmide when administered alone and in combination

The present study assesses the bioavailability of Ofloxacin (O) following single oral administration of the drug along with Rifampicin (R), or Isoniazid (H), or Pyrazinamide (Z) or a combination of three drugs. Information on the pharmacokinetics of O in the presence of R, H and Z based on the blood concentrations upto 8 hours, on the proportions of the doses of the drugs and their metabolites excreted in urine upto 8 hours and also the effect of O on the other antituberculosis (TB) drugs in terms of absorption and interactions are extensively studied. The bioavailability indices of these drugs are assessed. The investigation was undertaken in a total of 12 male healthy volunteers and each volunteer was investigated on four different occasions at weekly intervals. A partially balanced incomplete block design was employed and the allocation of O or the drug combinations was at random. Plasma concentrations of O, R, H and Z were determined. Urinary excretion of these drugs, together with their primary metabolites was also determined. Various pharmacokinetic parameters were calculated. The results have shown that the bioavailability of O is not impaired when administered with other antituberculosis drugs like R, H and Z and does not exercise any therapeutic penalty. The bioavailability of other anti-TB drugs like R, H and Z does not get affected when administered along with O. Human bioavailability studies, in general, provide direct straightforward information on the degree of absorption and biotransformation of drugs. The results of the present study indicate that the pharmacokinetic properties of O, R, H and Z as assessed after individual and combined administration of these drugs do not get affected or altered. Since there are no interactions among these drugs, the use of 0 in the treatment of pulmonary tuberculosis is justified

X-ray crystallographic and structural studies of (benzothiazol-2-yl)ethanesulphonamide, and its antimicrobial properties

N-(benzothiazol-2-yl)ethanesulphonamide (ES2ABT) was synthesized by the condensation of 2-aminobenzothiazole and ethanesulphonylchloride in acetone at 130 °C. The resulting crude precipitates were recrystallized in absolute ethanol. ES2ABT was characterized using X-ray crystallography, mass spectrometry, elemental microanalysis, UV/VIS spectrophotometry, infra red, proton and 13C NMR spectroscopies. The antimicrobial tests of the compound were carried out on both multi-resistant bacterial strains isolated under clinical conditions and cultured species using agar-well diffusion method. The multi-resistant bacterial strains used were Escherichia coli, Proteus species, Pseudomonas aeroginosa and Staphylococcus aureus which were isolated from dogs. The culture species were Pseudomonas aeruginosa (ATCC 27853), Escherichia Coli (ATCC 25922) Staphylococcus aureus (ATCC 25923), and the fungi, Candida krusei (ATCC 6258) and Candida albicans (ATCC 90028). The tests were both in vitro and in vivo. Thus the Inhibition Zone Diameter (IZD), the Minimum Inhibitory Concentration (MIC), and the Lethal and Effective Concentrations (LC50 and EC50) were determined. The antimicrobial activity of the compound was compared with those of Ciprofloxacin and trimethoprim-sulphamethoxazole as antibacterial agents and Fluconazole as an antifungal drug. The compound showed varying activity against the cultured typed bacteria and fungi used. However, ES2ABT was less active than the antibacterial standard drugs used but not Fluconazole which did not show any activity against Candida krusei (ATCC 6258). The Lethal Concentration (LC50) is 338.80 ± 28.6 ppm. This is within the permissible concentrations. Key words: N-(benzothiazol-2-yl)ethanesulphonamide, antimicrobial, in vivo, in vitr

Coupling of a single-photon emitter in nanodiamond to surface plasmons of a nanochannel-enclosed silver nanowire

A finite element method is applied to study the coupling between a nitrogen vacancy (NV) single photon emitter in nanodiamond and surface plasmons in a silver nanowire embedded in an alumina nanochannel template. We investigate the effective parameters in the coupled system and present detailed optimization for the maximum transmitted power at a selected optical frequency (650 nm). The studied parameters include nanowire length, nanowire diameter, distance between the dipole and the nanowire, orientation of the emitter and refractive index of the surrounding. It is found that the diameter of the nanowire has a strong influence on the propagation of the surface plasmon polaritons and emission power from the bottom and top endings of the nanowire. © 2014 Optical Society of America