Heated tobacco products- well known or well understood? A national cross-sectional study on knowledge, attitudes and usage in Pakistan.

BACKGROUND: Heated tobacco products (HTPs) are reshaping the tobacco industry and just recently, a plan was sought to regularize HTPs in Pakistan. Pakistan provides an intriguing case study in this context, as tobacco use is deeply ingrained in public use. To ensure that future evidence-based policy recommendations are grounded in the public's knowledge, attitudes, and usage of HTPs, a nationwide survey must be conducted. METHODS: A cross-sectional study was conducted using an online-based questionnaire nationwide in Pakistan. The questionnaire was validated and distributed through convenience sampling. The questionnaire assessed participants' knowledge, attitudes, and usage of HTPs. Descriptive statistics was used to describe participants' response and linear regression was performed at a p-value of < 0.05 using SPSS version 26. RESULTS: In our sample of 1195 respondents (mean age of 33 years, 41.8% males and 58.2% females), 54.7% had previously heard about HTPs and 16.9% reported using HTPs at least once. Additionally, 38.24% were unsure of the legality of HTP use. Those with monthly household incomes of PKR 100,000 to 500,000, were more likely to have higher knowledge scores (OR:1.80[1.07-3.04]). On the other hand, males (OR:0.70 [0.55-0.89]) and respondents from Balochistan (OR:0.40 [0.22-0.71]) were more likely to have lower knowledge scores. The strongest motivators were the enjoyability of HTPs (55.73%) and usage as a cigarette alternative (54.64%), while the strongest deterrents were the negative health effects (82.68%) and potential for addiction (81.01%). CONCLUSION: Our study underscores the need for awareness campaigns and interventions concerning HTPs, given prevalent preconceived notions and mixed attitudes among respondents. It was found that women and households with higher incomes scored higher on knowledge. Subjective enjoyment and a substitute for cigarettes were important motivators, but the most mentioned deterrents were the possibility of addiction and the detrimental effects on health. These insights form the basis for informed policy making for non-cigarette tobacco products.

Comparative study of five topological invariants of supramolecular chain of different complexes of N-salicylidene-L-valine.

L-valine is a crucial amino acid that has rising market demand and numerous uses. It can be used to make specific nutrients, animal feed additives, cosmetic ingredients, and other things in the medical and agricultural fields. N-salicylidene-L-valine (NsLv) is attracting a lot of attention due to its unusual structure and enhanced catalytic and cytotoxic activities. Topological index is a numerical value which is associated with the molecular structure. It is very helpful to predict physio-chemical properties and Quantitative structure-activity relationship and Quantitative structure-property relationship modeling. We study the supramolecular chain (Sc) in the dialkyl tin of complexes 2, 3 and 4 of NsLv to better understand this structure and its topological index-related characteristics. Additionally, we compare topological indices and analyze how these structures relate to one another using concrete examples.

Sequencing, biochemical characterization, crystal structure and molecular dynamics of cellobiohydrolase Cel7A from Geotrichum candidum 3C.

The ascomycete Geotrichum candidum is a versatile and efficient decay fungus that is involved, for example, in biodeterioration of compact discs; notably, the 3C strain was previously shown to degrade filter paper and cotton more efficiently than several industrial enzyme preparations. Glycoside hydrolase (GH) family 7 cellobiohydrolases (CBHs) are the primary constituents of industrial cellulase cocktails employed in biomass conversion, and feature tunnel-enclosed active sites that enable processive hydrolytic cleavage of cellulose chains. Understanding the structure-function relationships defining the activity and stability of GH7 CBHs is thus of keen interest. Accordingly, we report the comprehensive characterization of the GH7 CBH secreted by G. candidum (GcaCel7A). The bimodular cellulase consists of a family 1 cellulose-binding module (CBM) and linker connected to a GH7 catalytic domain that shares 64% sequence identity with the archetypal industrial GH7 CBH of Hypocrea jecorina (HjeCel7A). GcaCel7A shows activity on Avicel cellulose similar to HjeCel7A, with less product inhibition, but has a lower temperature optimum (50 °C versus 60-65 °C, respectively). Five crystal structures, with and without bound thio-oligosaccharides, show conformational diversity of tunnel-enclosing loops, including a form with partial tunnel collapse at subsite -4 not reported previously in GH7. Also, the first O-glycosylation site in a GH7 crystal structure is reported--on a loop where the glycan probably influences loop contacts across the active site and interactions with the cellulose surface. The GcaCel7A structures indicate higher loop flexibility than HjeCel7A, in accordance with sequence modifications. However, GcaCel7A retains small fluctuations in molecular simulations, suggesting high processivity and low endo-initiation probability, similar to HjeCel7A. DATABASE: Structural data are available in the Protein Data Bank under the accession numbers 5AMP, 4ZZV, 4ZZW, 4ZZT, and 4ZZU. The Geotrichum candidum GH family 7 cellobiohydrolase nucleotide sequence is available in GenBank under accession number KJ958925. ENZYMES: Glycoside hydrolase family 7 reducing end acting cellobiohydrolase.

A novel multiprotein complex is required to generate the prechylomicron transport vesicle from intestinal ER.

Dietary lipid absorption is dependent on chylomicron production whose rate-limiting step across the intestinal absorptive cell is the exit of chylomicrons from the endoplasmic reticulum (ER) in its ER-to-Golgi transport vesicle, the prechylomicron transport vesicle (PCTV). This study addresses the composition of the budding complex for PCTV. Immunoprecipitation (IP) studies from rat intestinal ER solubilized in Triton X-100 suggested that vesicle-associated membrane protein 7 (VAMP7), apolipoprotein B48 (apoB48), liver fatty acid-binding protein (L-FABP), CD36, and the COPII proteins were associated on incubation of the ER with cytosol and ATP. This association was confirmed by chromatography of the solubilized ER over Sephacryl S400-HR in which these constituents cochromatographed with an apparent kDa of 630. No multiprotein complex was detected when the ER was chromatographed in the absence of PCTV budding activity (resting ER or PKCzeta depletion of ER and cytosol). Treatment of the ER with anti-apoB48 or anti-VAMP7 antibodies or using gene disrupted L-FABP or CD36 mice all significantly inhibited PCTV generation. A smaller complex (no COPII proteins) was formed when only rL-FABP was used to bud PCTV. The data support the conclusion that the PCTV budding complex in intestinal ER is composed of VAMP7, apoB48, CD36, and L-FABP, plus the COPII proteins.