Chemical composition of Nigella sativa Linn : Part 2 Recent advances

The black cumin or Nigella sativa L. seeds have many acclaimed medicinal properties such as bronchodilatory, hypotensive, antibacterial, antifungal, analgesic, anti-inflammatory and immunopotentiating. This review article is an update on the previous article published on Nigella sativa L. in this journal in 1999. It covers the medicinal properties and chemical syntheses of the alkaloids isolated from the seeds of the herb

Non-Invasive Induction Link Model for Implantable Biomedical Microsystems: Pacemaker to Monitor Arrhythmic Patients in Body Area Networks

In this paper, a non-invasive inductive link model for an Implantable Biomedical Microsystems (IBMs) such as, a pacemaker to monitor Arrhythmic Patients (APs) in Body Area Networks (BANs) is proposed. The model acts as a driving source to keep the batteries charged, inside a device called, pacemaker. The device monitors any drift from natural human heart beats, a condition of arrythmia and also in turn, produces electrical pulses that create forced rhythms that, matches with the original normal heart rhythms. It constantly sends a medical report to the health center to keep the medical personnel aware of the patient's conditions and let them handle any critical condition, before it actually happens. Two equivalent models are compared by carrying the simulations, based on the parameters of voltage gain and link efficiency. Results depict that the series tuned primary and parallel tuned secondary circuit achieves the best results for both the parameters, keeping in view the constraint of coupling co-efficient (k), which should be less than a value \emph{0.45} as, desirable for the safety of body tissues.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

Prevalent phenotypes and antibiotic resistance in Escherichia coli and Klebsiella pneumoniae at an Indian tertiary care hospital: plasmid-mediated cefoxitin resistance

SummaryBackgroundThe β-lactam antibiotics, in combination with aminoglycosides, are among the most widely prescribed antibiotics. However, because of extensive and unnecessary use, resistance to these drugs continues to increase. In recent years, resistance in the Indian bacterial population has increased markedly, the majority showing complex mechanisms. Due to increased transcontinental movement of the human population, it would be wise to know the prevalence and resistance complexity of these strains, well in advance, in order to formulate a policy for empirical therapy.MethodsOne hundred and eighty-one isolates of Escherichia coli and 61 isolates of Klebsiella pneumoniae obtained from 2655 non-repeat samples of pus (912) and urine (1743) were studied, and their resistance rates and patterns were noted. The isolates were analyzed for prevalent aminoglycoside and cephalosporin resistance phenotypes and for the presence of extended spectrum β-lactamase (ESBL) and AmpC enzymes by spot-inoculation and modified three-dimensional tests developed in our laboratory. Fourteen isolates of E. coli and six of K. pneumoniae, resistant to all of the antibiotics tested, were selected for plasmid screening, curing, and transconjugation experiments, and for comparative evaluation of the double disk synergy test (DDST) and modified three-dimensional test (TDT) for detection of β-lactamases.ResultsUrinary E. coli isolates showed maximum susceptibility to amikacin (57.1%), followed by tobramycin (38.5%) and gentamicin (31.9%). Eighteen (19.8%) isolates were susceptible to cefotaxime, whereas 11 (12.1%) were susceptible to ceftriaxone. The K. pneumoniae isolates from urine samples showed maximum susceptibility to tobramycin (63.6%) followed by amikacin (54.5%). Of the K. pneumoniae isolates, 31.8% were susceptible to cefotaxime and 13.6% were susceptible to ceftriaxone. A more or less similar trend of antibiotic susceptibility was noted in E. coli and K. pneumoniae isolates from pus samples. Twenty-six (14.4%) E. coli and 15 (24.6%) K. pneumoniae isolates were found to be ESBL-producers by NCCLS-ESBL phenotypic confirmatory test. Eighteen (9.9%) E. coli and 19 (31.1%) K. pneumoniae isolates were found to be AmpC enzyme-producers by our modified TDT. The simultaneous occurrence of ESBL and AmpC enzymes was noted in 7.7% and 9.8% isolates of E. coli and K. pneumoniae, respectively.ConclusionsThe prevalence of multidrug-resistant bacterial isolates is quite high in our bacterial population. On comparative evaluation of DDST and TDT in resistant isolates, TDT was found to be the better method, detecting ESBLs in 80% of isolates compared to 15% with DDST. A 19.9-kb plasmid was consistently present in all the screened isolates of E. coli and K. pneumoniae, and was inferred to encode cefoxitin and tetracycline resistance based on curing and transconjugation experiments

Electronic Tuning of Zinc Oxide by Direct Fabrication of Chromium (Cr) incorporated photoanodes for Visible-light driven Water Splitting Applications

This is the final version. Available on open access from Nature Research via the DOI in this recordHerein, we report the synthesis of Cr incorporated ZnO sheets arrays microstructures and construction of photoelectrode through a direct aerosol assisted chemical vapour deposition (AACVD) method. The as-prepared Cr incorporated ZnO microstructures were characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, powdered X-ray spectroscopy, X-ray photoelectron spectroscopy and UV-Vis diffused reflectance spectroscopy. The Cr incorporation in ZnO red shifted the optical band gap of as-prepared photoanodes. The 15% Cr incorporation in ZnO has shown enhanced PEC performance. The AACVD method provides an efficient in situ incorporation approach for the manipulation of morphological aspects, phase purity, and band structure of photoelectrodes for an enhanced PEC performance.Higher Education Commission of PakistanUniversity of Mancheste