Amphiphilic Block Copolymers Containing Benzenesulfonyl Azide Groups as Visible Light-Responsive Drug Carriers for Image-Guided Delivery.

Nanoparticles (NPs) containing light-responsive polymers and imaging agents show great promise for controlled drug delivery. However, most light-responsive NPs rely on short-wavelength excitation, resulting in poor tissue penetration and potential cytotoxicity. Moreover, excessively sensitive NPs may prematurely release drugs during storage and circulation, diminishing their efficacy and causing off-target toxicity. Herein, we report visible-light-responsive NPs composed of an amphiphilic block copolymer containing responsive 4-acrylamide benzenesulfonyl azide (ABSA) and hydrophilic N,N'-dimethylacrylamide (DMA) units. The polymer pDMA-ABSA was loaded with the chemotherapy drug dasatinib and zinc tetraphenylporphyrin (ZnTPP). ZnTPP acted as an imaging reagent and a photosensitizer to reduce ABSA upon visible light irradiation, converting hydrophobic units to hydrophilic units and disrupting NPs to trigger drug release. These NPs enabled real-time fluorescence imaging in cells and exhibited synergistic chemophotodynamic therapy against multiple cancer cell lines. Our light-responsive NP platform holds great promise for controlled drug delivery and cancer theranostics, circumventing the limitations of traditional photosensitive nanosystems.

Epidemiology of gastroesophageal reflux disease: a general population-based study in Xi'an of Northwest China.

AIM: Gastroesophageal reflux disease (GERD) is a common disorder in the Western population, but detailed population-based data in China are limited. The aim of this study was to understand the epidemiology of symptomatic gastroesophageal reflux (SGER) in adults of Xi'an, a northwestern city of China, and to explore the potential risk factors of GERD. METHODS: Symptoms suggestive of GERD, functional dyspepsia (FD), irritable bowel syndrome (IBS), upper respiratory diseases and some potential risk factors were investigated in a face-to-face manner in a region-stratified random samples of 2789 residents aged 18-70 years in Xi'an by using a standardized questionnaire. METHODS: With a response rate of 91.8%, the prevalence of SGER was 16.98% (95% CI, 14.2-18.92) in Xi'an adults, and no gender-related difference was observed (P<0.05). SGER was more common among subjects aged 30-70 years than in those aged 18-29 years (P<0.01). The prevalence of SGER in rural, urban and suburban subjects was 21.07%, 17.44% and 12.12%, respectively, and there was a significant difference between rural, urban and suburban regions (P<0.05). Compared with subjects without SGER, the prevalence of symptoms suggestive of FD and IBS, pneumonia, asthma, bronchitis, laryngitis, pharyngitis, chronic cough, wheeze, globus sensation, oral ulcer and snore was significantly increased in subjects with SGER (P<0.01). Heavy smoking (OR=5.76; CI, 3.70-6.67), heavy alcohol use (OR=2.85; CI, 1.67-4.49), peptic ulcer (OR=5.76; CI, 3.99-8.32), cerebral palsy (OR=3.97; CI, 1.97-8.00), abdominal operation (OR=2.69; CI, 1.75-4.13), obesity (OR=2.16; CI, 1.47-3.16), excessive food intake (OR=1.43; CI, 1.17-1.15), sweet food (OR=1.23; CI, 0.89-1.54), and consumption of coffee (OR=1.23; CI, 0.17-2.00) were independently associated with SGER. The episodes of GERD were commonly precipitated by dietary factors (66.05%), followed by body posture (26.54%), ill temper (23.72%), fatigue (22.32%) and stress (10.93%). CONCLUSION: GERD is common in Xi'an's adult population with a mild or moderate degree. The etiology and pathogenesis of GERD are probably associated with FD, IBS, and some respiratory, laryngopharyngeal and odontostological diseases or symptoms. Some lifestyles, diseases and dietary factors are the risk factors of GERD.