Impact of Presence of Children on Indoor Tobacco Restrictions in Households of Urban and Rural Adult Tobacco Users

Objectives

Secondhand smoke exposure in children is changing as a result of new public policy and electronic nicotine products (e-cigarettes). We examined factors related to self-imposed indoor household tobacco restrictions, with emphasis on children in the household and associations with combustible and noncombustible product use.

Escherichia coli O157 in the rectoanal mucosal region of cattle

The rectoanal junction mucosal region is the site of colonization of Escherichia coli O157 in cattle. Our objective was to determine the genetic relatedness of E. coli O157 in the mucosa of the rectoanal junction to isolates from colon contents and feces. Colon contents and rectums were collected from cattle at harvest. Rectums were opened and feces were sampled with a cotton swab. The mucosa of the rectum was cleansed free of visible feces with water and saline. The region, 2 to 5 cm proximal to the rectoanal junction, was swabbed with a foam-tipped applicator and then incisions were made in this region and the submucosa was swabbed with an applicator. Isolation and identification of E. coli O157 was performed in accordance with well-documented methods. Prevalence of E. coli O157 in the colon contents, feces, rectal mucosa, and rectal submucosa was 21%, 29%, 54%, and 34%, respectively. Pulsed-field gel electrophoresis was used to compare clonal similarity among isolates from different sampling regions. Sixty-seven cattle had E. coli O157 isolated from the rectal mucosa swab and feces of which 82% were clonally similar (dice similarity >95%) within animal. Escherichia coli O157 isolates from feces and colon contents were similar in 76% of cattle, but E. coli O157 isolates from the rectoanal mucosal swab and colon contents were only similar in 61.4% of cattle. Our results suggest that E. coli O157 in the feces may be from two sources, colonized in the rectoanal mucosa or transient in the gastrointestinal tract.     

Transcriptional Dependencies in Diffuse Intrinsic Pontine Glioma

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Paraffin-embedded tissue as a source of RNA for gene expression analysis in oral malignancy

OBJECTIVE: To assess the feasibility of using archival oral mucosal tissue to examine gene expression at the ribonucleic acid (RNA) level.
MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion.     

Spectrophotometric methods for the rapid determination of menadione and menadione sodium bisulphite and their application in pharmaceutical preparations

Two simple, rapid and sensitive spectrophotometric determination of menadione and its sodium bisulphite derivative (MSB) have been carried out. The first method involves the reaction of menadione and its sodium bisulphite derivative with 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) is sodium hydroxide medium to give blue coloured product having maximum absorption at 625 nm and the coloured species is stable for more than 1 h. The Beer's law is obeyed in the range 0.4-16 microg ml(-1). The second method proposes the reaction of menadione and its sodium bisulphite derivative with resorcinol in concentrated sulphuric acid medium to give red coloured product having maximum absorption at 520 nm and is stable for 3 h. The Beer's law was obeyed in the range of 1-24 microg ml(-1). Molar absorptivity for the above two methods were found to be 7.6 x 10(3) and 4.5 x 10(3) l mol(-1) cm(-1), respectively. All the measurements were carried out at room temperature. These two methods have been successfully applied for menadione and its sodium bisulphite derivatives in injections and tablets of pharmaceutical formulations. The results compare favourably with official method.     

Stability indicating RP-LC determination of sildenafil citrate (Viagra) in pure form and in pharmaceutical samples

A simple, precise, sensitive and stability-indicating reverse-phase high performance liquid chromatographic (RP-HPLC) method has been developed for the quantitation of sildenafil citrate (SC) in pure form and its pharmaceutical formulations. Method employs water and acetonitrile (48:52 v/v) as mobile phase with flow rate of 1 ml min(-1), LiChrospher C18-5 microm (25 x 0.46 cm) column and UV detection set at 245 nm. The internal standard method using piroxicam (PX) as the internal standard is used. The linear dynamic range of SC was found to be 0.05-7.5 microg ml(-1). The proposed method is successfully employed for the determination of SC in the tablets. The excipients present in the formulations do not interfere with the assay procedure. Analytical parameters were calculated and full statistical evaluation is included.     

Influence of Heat Treatment and Reinforcements on Tensile Characteristics of Aluminium AA 5083/Silicon Carbide/Fly Ash Composites

The effect of reinforcements and thermal exposure on the tensile properties of aluminium AA 5083–silicon carbide (SiC)–fly ash composites were studied in the present work. The specimens were fabricated with varying wt.% of fly ash and silicon carbide and subjected to T6 thermal cycle conditions to enhance the properties through “precipitation hardening”. The analyses of the microstructure and the elemental distribution were carried out using scanning electron microscopic (SEM) images and energy dispersive spectroscopy (EDS). The composite specimens thus subjected to thermal treatment exhibit uniform distribution of the reinforcements, and the energy dispersive spectrum exhibit the presence of Al, Si, Mg, O elements, along with the traces of few other elements. The effects of reinforcements and heat treatment on the tensile properties were investigated through a set of scientifically designed experimental trials. From the investigations, it is observed that the tensile and yield strength increases up to 160 °C, beyond which there is a slight reduction in the tensile and yield strength with an increase in temperature (i.e., 200 °C). Additionally, the % elongation of the composites decreases substantially with the inclusion of the reinforcements and thermal exposure, leading to an increase in stiffness and elastic modulus of the specimens. The improvement in the strength and elastic modulus of the composites is attributed to a number of factors, i.e., the diffusion mechanism, composition of the reinforcements, heat treatment temperatures, and grain refinement. Further, the optimisation studies and ANN modelling validated the experimental outcomes and provided the training models for the test data with the correlation coefficients for interpolating the results for different sets of parameters, thereby facilitating the fabrication of hybrid composite components for various automotive and aerospace applications.