Development and characterization of electronic-cigarette exposure generation system (Ecig-EGS) for the physico-chemical and toxicological assessment of electronic cigarette emissions

Electronic cigarettes (e-cig) have been introduced as a nicotine replacement therapy and have gained increasing attention and popularity. However, while findings on possible toxicological implications continue to grow, major knowledge gaps on both the complex chemistry of the exposure and toxicity exist, prohibiting public health assessors from assessing risks. Here, a versatile electronic cigarette exposure generation system (Ecig-EGS) has been developed and characterized. Ecig-EGS allows generation of real world e-cig emission profiles under controlled operational conditions, real time monitoring and time-integrated particle/gas sampling for physico-chemical characterization, and toxicological assessment (both in vitro and in vivo). The platform is highly versatile and can be used with all e-cig types. It enables generation of precisely controlled e-cig exposure while critical operational parameters and environmental mixing conditions can be adjusted in a systematic manner to assess their impact on complex chemistry and toxicity of emissions. Results proved the versatility and reproducibility of Ecig-EGS. E-cig emission was found to contain 10⁶–10⁷ particles/cm³ with the mode diameter around 200?nm, under air change rate of 60/h. Elevated CO₂ and volatile organic specie generation was also observed. Furthermore, environmental mixing conditions also influenced e-cig emission profile. The versatility of Ecig-EGS will enable linking of operational and environmental parameters with exposure chemistry and toxicology and help in assessing health risks.     

A computerized exposure system for animal models to optimize nicotine delivery into the brain through inhalation of electronic cigarette vapors or cigarette smoke

Pre-clinical studies investigated the effects of chronic exposure to nicotine on lungs, kidneys and brains using animal models. Most of these studies delivered nicotine into the circulatory and central nervous systems (CNS) through intraperitoneal injection or oral consumption methods. Few studies used inhalation machine system for nicotine delivery into brains in rodents to mimic human exposure to cigarettes. However, finding a more accurate and clinically relevant method of nicotine delivery is critical. A computerized inhalation machine has been designed (SciReq) and is currently employed in several institutions. The computerized machine delivers electronic (e)-cigarette vapor as well as tobacco smoke to rodents using marketed e-cigarette devices or tobacco cigarettes. This provides evidence about clinical effects of nicotine delivery by traditional methods (combustible cigarettes) and new methodologies (e-cigarettes) in physiological systems. Potential neurobiological mechanisms for the development of nicotine dependence have been determined recently in mice exposed to e-cigarette vapors in our laboratory using SciReq system. In this review article, the discussion focuses on the efficiency and practical applicability of using this computerized inhalation exposure system in inducing significant changes in brain protein expression and function as compared to other nicotine delivery methods. The SciReq inhalation system utilized in our laboratory and others is a method of nicotine delivery to the CNS, which has physiological relevance and mimics human inhalant exposures. Translation of the effects of inhaled nicotine on the CNS into clinical settings could provide important health considerations.     

Preparation and in vitro characterization of glibenclamide-loaded alginate hexyl-amide beads: a novel drug delivery system to improve the dissolution rate

Abstract

Objective: This investigation aimed to synthesize amphiphilic hexyl amidic derivative of alginate to be used in the preparation of glibenclamide-loaded release system of improved dissolution rate.

Materials and methods: Hexyl amine was associated to the activated carboxylic acid moieties of alginate to synthesize alginate hexyl amide polymer (AHAP). This polymer in comparison to alginate was used in different concentrations for preparing beads containing glibenclamide by an ionic gelation using Ca⁺⁺ as gelling ion. The prepared beads were characterized by DSC, FTIR and scanning electron microscope. The swelling behavior, drug loading capacity and release behavior were studied.

Results and discussion: The results showed that the prepared AHAP beads were smaller in size and more spherical. The surface was highly corrugated with much and wider pore size. The beads showed a high drug loading capacity and efficacy that was affected by the polymer concentration. The drug release rate from AHAP beads reached 100% after 4, 8 and 12 hours in comparison to 75.3%, 73.2% and 69.2% from alginate beads at 3%, 2% and 1% polymer concentrations, respectively.

Conclusion: It can thus be concluded that the amphiphilic AHAP-based bead is a simple and efficient delivery system of promising industrial significance for the improvement of the dissolution rate.     

选择最佳氧气流量对AECOPD患者实施氧气雾化吸入的临床研究

目的探讨老年AECOPD患者进行氧气雾化吸入疗法时最适宜的氧流量。方法对125例采取氧气雾化吸入疗法的AECOPD患者,按照4L/min,5L/min,6L/min,7L/min,8L/min的氧流量随机分为5组,观察患者雾化吸入前后的心率、末梢脉氧饱和度、患者舒适度及1小时内咯痰量的变化。结果氧气流量为6L/min,患者舒适度得分最高,同时1h咯痰量最多。组间比较,舒适度得分均有差异(P<0.05);6L/min氧流量的1h内咯痰量与4L/min、5L/min比较有明显差异(P<0.05);氧流量4～6L/min时,雾化前后心率变化较小(P>0.05),7～8L/min时,雾化前后心率变化较大(P<0.05);各组雾化后脉氧均明显增加增加(P<0.05)。结论在AECOPD患者进行氧气雾化疗法时,采用氧流量在6L/min,可达到最佳的雾化效果。     

Making the case for integrated assessments of the biological,social, and system determinants of treatment for breast cancer to understand and improve outcomes in patients everywhere

Abstract

Breast cancer treatment requires multidisciplinary action, which entails the collaboration of healthcare professionals with the goal of improving outcomes in a particular group of patients. Multidisciplinary actions target for example various components of the health care process, including medication regimens, lifestyle modifications, self-management, and patient education. Health care professionals need to understand and manage the cultural diversity of patients and avoid allowing unconscious biases and stereotypes to affect their interactions with patients.