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Abstract  

The object of the present paper is to study quasi-conformally flat weakly Ricci symmetric manifolds.

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Abstract  

Forty brands of tobacco used in Indian cigarettes, 20 brands of bidis (tobacco rolled in wrapper leaves), 15 brands of chewing tobacco and 15 brands of snuff tobacco were analyzed by nuclear and allied techniques. The elements measured into tobacco can be grouped into seven categories from less than 1 ppm to 5% by weight. Concentration level varied from 0.5-5% for (Ca, K, Cl), 400-1500 ppm (Fe), 200-600 ppm (Na), 100-300 ppm (Ti, Mn, Br and Sr), 10-100 ppm (Cu, Zn and Rb), 1-10 ppm (Cr, Ni, Pb and La) and less than 1 ppm (As, Co, Cd, Sb, Hg and Eu). Among the above elements Cr, Ni, As, Cd, Pb, Hg and Sb are considered toxic. The percentage transfer of the elements from cigarette tobacco to smoke particles during smoking was also estimated using a smoking machine and collecting the smoke particles on a filter paper. The results show that Br, Cr, Sb and Zn have high percentage transfer from tobacco to its smoke of the order of 2-15%. Out of these Sb has the highest 15%. Cobalt, Fe and Sc have lowest percentage of transfer of the order of less than 1%. The percent transfer of these elements from tobacco to tobacco smoke is higher in case of bidis (1.5-3.0 times) as compared to cigarettes. In cigarettes also non-filter cigarettes have higher transfer (2-3 times) as compared to filter tip cigarettes.

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Abstract  

The object of the present paper is to study decomposable weakly conformally symmetric Riemannian manifolds with several non-trivial examples.

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The impact of high temperature stress, normally encountered during grain development phases in wheat under late sown conditions, was studied by measuring grain growth rate (mg day−1 grain−1), grain yield (g plant−1) in relation to ADP glucose pyrophosphorylase (AGPase) activity (nmol mg−1 min−1), a key regulatory enzyme in starch biosynthesis. The experimental material comprised nine genetically diverse homozygous genotypes of spring wheat and their six F1s. These were grown in randomised block design with three replications at CCS Haryana Agricultural University, Hisar, India on two dates of sowing 26th November, 2007 (timely, E1) and 24th December, 2007 (late, E2). The rate of grain growth was greatly reduced as temperature increased in late sown environment. Grain growth rate among the parental genotypes was highest in UP 2425 and cross PBW 343 × PBW 435 in both the environments. Mean ADP glucose pyrophosphorylase (AGPase) activity was maximum at 14 days after anthesis in timely sown while in late sown the activity was maximum at 21 days after anthesis in PBW 435, EIGN 1 and EIGN 8 and crosses EIGN 8 × UP 2425, EIGN 1 × Raj 3765 and PBW 343 × PBW 435. A significant positive association in both timely and late sown environments was evident between grain yield and grain growth rate, while in late sown environment, strong positive and significant correlation was observed between grain yield and grain growth rate and also between grain growth rate and AGPase activity in crosses PBW 343 ×WH 283, PBW 343 × WH 542 and PBW 343 × PBW 435. This suggested that increase in grain growth rate and AGPase activities resulted in increase in grain yield and have considerable impact on the yield performance of wheat.

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Abstract  

Toxic trace metals like mercury, arsenic and cadmium have been determined in widely used Indian chewing tobacco and cigarette tobacco by neutron activation followed by sequential radiochemical separation (RNAA). Differential Pulse Anodic Stripping Voltammetry (DPASV) has been used for the estimation of lead, cadmium and copper in cigarette tobacco and its smoke aerosols. The reliability of the data has been assured by analyzing standard reference materials, bovine liver (NBS-1577) and orchard leaves (NBS-1571), and intercomparison of the Pb, Cd and Cu values by three techniques, namely, RNAA, DPASV and Energy Dispersive X-ray Flourescence technique (EDXRF). The levels of Hg, Cd, As, Pb and Cu in cigarette and chewing tobacco and the estimated intake of Cd, Cu and Pb to the smoker are presented and discussed.

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Abstract  

The present study is performed to compare the electrophilic substitution radioiodination reaction of two non-steroidal anti-inflammatory drugs namely, Piroxicam (Pirox) and Meloxicam (Melox) with 125I where both chloramine-T (CAT) and iodogen were used as oxidizing agents. The factors affecting the percent of radiochemical yields such as drug concentration, pH of the reaction mixtures, different oxidizing agents, reaction time, temperature and different organic media were studied to optimize the conditions for labeling of Pirox and Melox and to obtain high radiochemical yields. The maximum radiochemical yield of 125I-Piroxicam (125I-Pirox) was 94% using 3.7 MBq of Na125I, 0.4 mM of Pirox as substrate, 3.6 mM of chloramine-T (CAT) as oxidizing agent in acetone at neutral pH = 7 and at 60 °C within 20 min where the maximum radiochemical yield of 125I-Melox was 92% using 0.7 mM of Melox as substrate, 0.62 mM of iodogen as oxidizing agent in acetone at neutral pH = 7 and at 25 °C within 30 min. The radiochemical yields were determined by TLC and high-pressure liquid chromatography (HPLC). Tracers showed good localization in inflamed muscle either septic or sterile. The collected data indicates that Pirox and Melox can be used as antiinflammatory imaging agents at 24 and 2 h post injection, respectively.

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Abstract  

This study describes a fast and efficient method for radiolabeling of etodolac with iodine-125 [125I], where both chloramine-T and iodogen were used as oxidizing agents. The labeling reaction was carried out via electrophilic substitution of hydrogen atom with the iodonium cation I+. The labeling yield was found to be influenced by different factors such as drug concentration, pH of the reaction mixtures, different oxidizing agents, reaction time, temperature and different organic media. The radiochemical yield (RCY) was determined by TLC system using methylene chloride:ethyl acetate (3:7 v/v) as a developing solvent and by electrophoresis using cellulose acetate moistened with 0.02 M phosphate buffer pH 7. The maximum radiochemical yield of [125I]Etodolac (87.7%) was obtained. Labeled etodolac shows a good localization in inflamed muscle. It excretes mainly via kidney and to some via liver.

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Summary

A stability-indicating reversed-phase high-performance liquid chromatographic method has been developed for analysis of gemifloxacin in tablet formulations. When the drug was subjected to forced degradation under acidic, basic, thermal, oxidative, and photolytic conditions, the degradation products produced were successfully separated on a 250 mm × 4.6 mm, 5-μm particle, C18 column with ammonium acetate buffer (pH 2.7; 0.05 m)-acetonitrile 70:30 (υ/υ) as mobile phase at a flow rate of 0.7 mL min−1. Diode-array detection was performed at 272 nm. The method was validated in accordance with ICH guidelines. Response was a linear function of concentration over the range 0.256–128 μg mL−1 (correlation coefficient 0.9990). The limits of detection and quantification were 10 and 30 ng mL−1, respectively. Separation of gemifloxacin from its stress-induced degradation products and excipients was adequate; resolution was >1.5 within 11 min. The purity index for the gemifloxacin peak after all types of stress was >0.999, indicating complete separation of the analyte peak from the degradation products. The method can therefore be regarded as stability-indicating. It is rapid, and suitable for purity and assay determination not only for routine quality control but also in stability studies.

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European Journal of Microbiology and Immunology
Authors: E. Sapi, K. Balasubramanian, A. Poruri, J. S. Maghsoudlou, K. M. Socarras, A. V. Timmaraju, K. R. Filush, K. Gupta, S. Shaikh, P. A. S. Theophilus, D. F. Luecke, A. MacDonald, and B. Zelger

Lyme borreliosis, caused by the spirochete Borrelia burgdorferi sensu lato, has grown into a major public health problem. We recently identified a novel morphological form of B. burgdorferi, called biofilm, a structure that is well known to be highly resistant to antibiotics. However, there is no evidence of the existence of Borrelia biofilm in vivo; therefore, the main goal of this study was to determine the presence of Borrelia biofilm in infected human skin tissues. Archived skin biopsy tissues from borrelial lymphocytomas (BL) were reexamined for the presence of B. burgdorferi sensu lato using Borrelia-specific immunohistochemical staining (IHC), fluorescent in situ hybridization, combined fluorescent in situ hybridization (FISH)–IHC, polymerase chain reaction (PCR), and fluorescent and atomic force microscopy methods. Our morphological and histological analyses showed that significant amounts of Borrelia-positive spirochetes and aggregates exist in the BL tissues. Analyzing structures positive for Borrelia showed that aggregates, but not spirochetes, expressed biofilm markers such as protective layers of different mucopolysaccharides, especially alginate. Atomic force microscopy revealed additional hallmark biofilm features of the Borrelia/alginate-positive aggregates such as inside channels and surface protrusions. In summary, this is the first study that demonstrates the presence of Borrelia biofilm in human infected skin tissues.

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