البحث و الابتكار

Abstract Background: The rising use of e-cigarettes among adolescents presents a growing public health concern, particularly in countries like Saudi Arabia, where tobacco marketing regulation is still evolving. Although marketing is a known driver of youth tobacco uptake, evidence from the Eastern Mediterranean region remains limited. This study examined the association between exposure to e-cigarette marketing and current use among Saudi adolescents using nationally representative data. Methods: We analysed cross-sectional data from the 2022 Global Youth Tobacco Survey (GYTS) in Saudi Arabia, a nationally representative, school-based survey of adolescents aged 13–15 years. Key exposures included seeing a point-of-sale (POS) advertisement and being offered a free e-cigarette. A composite marketing exposure score (0, 1, or 2 exposures) was created. The outcome was current e-cigarette use, defined as use on at least one day in the past 30 days. Survey-weighted logistic regression models estimated crude and adjusted odds ratios (aORs), adjusting for age, sex, parental smoking, and peer smoking. Sex-stratified analyses were also conducted. Results: Among 5,610 adolescents, 300 (5.4%) reported current e-cigarette use. Of all respondents, 5.7% had been offered a free e-cigarette and 19.7% had seen a POS advertisement. Both exposures were significantly associated with current e-cigarette use: free product offer (aOR: 6.57; 95% CI: 4.61–9.36; p < 0.001) and POS ad exposure (aOR: 2.66; 95% CI: 1.79–3.97; p < 0.001). A dose–response relationship was observed, with those exposed to both forms of marketing having 15 times the odds of current use (aOR: 15.05; 95% CI: 7.81–29.02; p < 0.001). Associations were significant for both males and females. Conclusion: Exposure to e-cigarette marketing is a strong and consistent predictor of adolescent use in Saudi Arabia. These findings support urgent policy action to restrict youth-targeted tobacco promotions.

Since the discovery of proprotein convertase subtilisin kexin 9 (PCSK9) in 2003, this PC has attracted a lot of attention from the scientific community and pharmaceutical companies. Secreted into the plasma by the liver, the proteinase K–like serine protease PCSK9 binds the low-density lipoprotein (LDL) receptor at the surface of hepatocytes, thereby preventing its recycling and enhancing its degradation in endosomes/lysosomes, resulting in reduced LDL-cholesterol clearance. Surprisingly, in a nonenzymatic fashion, PCSK9 enhances the intracellular degradation of all its target proteins. Rare gain-of-function PCSK9 variants lead to higher levels of LDL-cholesterol and increased risk of cardiovascular disease; more common loss-of-function PCSK9 variants are associated with reductions in both LDL-cholesterol and risk of cardiovascular disease. It took 9 years to elaborate powerful new PCSK9-based therapeutic approaches to reduce circulating levels of LDL-cholesterol. Presently, PCSK9 monoclonal antibodies that inhibit its function on the LDL receptor are evaluated in phase III clinical trials. This review will address the biochemical, genetic, and clinical aspects associated with PCSK9’s biology and pathophysiology in cells, rodent and human, with emphasis on the clinical benefits of silencing the expression/activity of PCSK9 as a new modality in the treatment of hypercholesterolemia and associated pathologies.

Navigated total knee arthroplasty (TKA) is promoted as a means to improve limb and prosthesis alignment. This study involved a systematic review and meta-analysis for all randomized controlled trials in the literature from 1986 to 2009 comparing alignment outcomes between navigated and conventional TKA. Alignment outcomes were pooled using a random-effects model, and heterogeneity was explored. Twenty-three randomized controlled trials were identified comparing navigated vs conventional TKA involving 2541 patients. Patients who underwent navigated TKA had a significantly lower risk of implant malalignment at more than 3° as well as more than 2°. In addition, the risk of malalignment was reduced for the coronal plane tibial and femoral components as well as femoral and tibial slope. This meta-analysis demonstrates that navigated TKA provides significant improvement in prosthesis alignment.