Poor water solubility is the primary obstacle preventing the development of many pharmacologically active compounds into oral preparations. Self-nanoemulsifying drug delivery systems(SNEDDS) have become a widely used strategy to enhance the oral bioavailability of poorly soluble drugs by inducing a supersaturated state, thereby improving their apparent solubility and dissolution rate. However, the supersaturated solutions formed in SNEDDS are thermodynamically unstable systems with solubility levels exceeding the crystalline equilibrium solubility, making them prone to drug precipitation in the gastrointestinal tract and ultimately hindering drug absorption. Therefore, maintaining a stable supersaturated state is crucial for the effective delivery of poorly soluble drugs. Incorporating polymers as precipitation inhibitors(PPIs) into the formulation of supersaturated self-nanoemulsifying drug delivery systems(S-SNEDDS) can inhibit drug aggregation and crystallization, thus maintaining a stable supersaturated state. This has emerged as a novel preparation strategy and a key focus in SNEDDS research. This review explores the preparation design of SNEDDS and the technical challenges involved, with a particular focus on polymer-based S-SNEDDS for enhancing the solubility and oral bioavailability of poorly soluble drugs. It further elucidates the mechanisms by which polymers participate in transmembrane transport, summarizes the principles by which polymers sustain a supersaturated state, and discusses strategies for enhancing drug absorption. Altogether, this review provides a structured framework for the development of S-SNEDDS preparations with stable quality and reduced development risk, and offers a theoretical reference for the application of S-SNEDDS technology in improving the oral bioavailability of poorly soluble drugs.
Solubility ; Administration, Oral ; Polymers/chemistry* ; Drug Delivery Systems/methods* ; Humans ; Emulsions/chemistry* ; Biological Availability ; Animals ; Pharmaceutical Preparations/administration & dosage*

BACKGROUNDWith industrial and econom ic development in recent decades in South China, cancer incidence may have changed due to the changing lifestyle and environment. However, the trends of lung cancer and the roles of smoking and other environmental risk factors in the development of lung cancer in rural areas of South China remain unclear. The purpose of this study was to explore the lung cancer incidence trends and the possible causes of these trends.

METHODSJoinpoint regression analysis and the age-period-cohort (APC) model were used to analyze the lung cancer incidence trends in Sihui, Guangdong province, China between 1987 and 2011, and explore the possible causes of these trends.

RESULTSA total of 2,397 lung cancer patients were involved in this study. A 3-fold increase in the incidence of lung cancer in both sexes was observed over the 25-year period. Joinpoint regression analysis showed that while the incidence continued to increase steadily in females during the entire period, a sharp acceleration was observed in males starting in 2005. The full APC model was selected to describe age, period, and birth cohort effects on lung cancer incidence trends in Sihui. The age cohorts in both sexes showed a continuously significant increase in the relative risk (RR) of lung cancer, with a peak in the eldest age group (80-84 years). The RR of lung cancer showed a fluctuating curve in both sexes. The birth cohorts identified an increased trend in both males and females; however, males had a plateau in the youngest cohorts who were born during 1955-1969.

CONCLUSIONSIncreasing trends of the incidence of lung cancer in Sihui were dominated by the effects of age and birth cohorts. Social aging, smoking, and environmental changes may play important roles in such trends.

Aging ; China ; Female ; Humans ; Incidence ; Lung Neoplasms ; Male ; Risk Factors ; Smoking

Objective To assess the value of three-dimensional contrast-enhanced ultrasonography (3D-CEUS) in evaluation of hepatic arteries variants.Methods Both two-dimensional contrast-enhanced ultrasonography (2D-CEUS) and 3D-CEUS were used to assess 30 patients including living donor candidates and patients with upper abdomen tumors.The reference standard was operation or CTA or DSA or MRA,and the accuracy for detecting hepatic artery variants provided by the two methods was evaluated.Arterial anatomic types were defined by using Michels classification.Results The total accuracy for detecting hepatic artery anatomy types by 2D-CEUS was 40.0% (12/30),while 83.3% (25/30) by 2D-CEUS.For convention anatomy types the accuracy on 2D-CEUS and 3D-CEUS were 40.9%(9/22)and 90.9%(20/22),respectively.The difference was statistically significant (P<0.05).For anatomy variants types the accuracy on 2D-CEUS and 3D-CEUS were 37.5%(3/8)and 62.5%(5/8),respectively.No significant difference between these two methods was observed.Conclusion 3D-CEUS was a new method in diagnosis of hepatic arteries anatomy types with practical clinical value in evaluation of the living liver donors.