Photocatalytic Three-Component Reaction for the Synthesis of Multifunctional Diaryl Sulfides.

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

Mental health issues in parents of children with autism spectrum disorder: A multi-time-point study related to COVID-19 pandemic.

Given the unpredictability and challenges brought about by the 2019 novel coronavirus (COVID-19) pandemic, this study aimed to investigate the impact trend of the prolonged pandemic on the mental health of parents of children with autism spectrum disorder (ASD). The 8112 participants included parents of children with ASD and parents of typically developing (TD) children at two sites (Heilongjiang and Fujian province, China). The parents completed a set of self-report questionnaires covering demographic characteristics, influences related to COVID-19, COVID-19 concerns and perceived behaviors, as well as the Connor-Davidson resilience scale (CD-RISC), self-rating anxiety scale (SAS), and self-rating depression scale (SDS) by means of an online survey platform. Data were collected by three cross-sectional surveys carried out in April 2020 (Time 1), October 2020 (Time 2), and October 2021 (Time 3). The results of quantitative and qualitative comparisons showed that: (i) parents of children with ASD had lower levels of resilience, and more symptoms of anxiety and depression than parents of TD children at each time point (all P < 0.05); and (ii) there were significant time-cumulative changes in resilience, anxiety, and depression among all participants (all P < 0.05). The logistic regression analyzes after adjusting for demographic characteristics revealed that the following factors were significantly associated with poor resilience and a higher rate of anxiety and depression in parents of children with ASD: time-point, the effect of COVID-19 on children's emotions and parents' emotions, changes in relationships, changes in physical exercise, changes in daily diet during the COVID-19 pandemic, and COVID-19-related psychological distress. In conclusions, the parents did not report improvements in resilience, anxiety, or depression symptoms from Time 1 to Time 2 or 3, indicating that cumulative mental health issues increased when, surprisingly, the COVID-19 restrictions were eased. The psychological harm resulting from the COVID-19 pandemic is far-reaching, especially among parents of children with ASD.

Floating matrix dosage form for dextromethorphan hydrobromide based on gas forming technique: in vitro and in vivo evaluation in healthy volunteers.

The objective of this study was to develop the dextromethorphan hydrobromide sustained-release (DMB-SR) tablets using floating technique to prolong the gastric residence time and compared their pharmacokinetic behavior with conventional sustained release tablets. DMB-SR floating tablets were prepared employing hydroxypropyl methylcellulose (HPMC) as hydrophilic gel material, sodium bicarbonate as gas-generating agent and hexadecanol as floating assistant agent. An orthogonal experiment design method was used to select the optimized formulation. The floating tablets were evaluated for uniformity of weight, hardness, friability, drug content, floating characteristics, in vitro release and in vivo bioavailability. The optimized tablets were prepared with HPMC K4M 25 mg, sodium bicarbonate 20 mg and hexadecanol 18 mg. The prepared tablets could float within 3 min and maintain for more than 24 h. The data of physical parameters were all lie within the limits. Drug release at 12 h was more than 85%. The comparative pharmacokinetic study was performed by administration of the DMB-SR floating tablets and conventional DMB-SR tablets. The area under curve of plasma concentration-time (AUC) of floating tablets was slightly higher than that of reference tablets, T(max) was prolonged apparently. The results showed the floating tablets are a feasible approach for the sustained-release preparation of drugs, which have limited absorption sites in the stomach.

Preparation of rosiglitazone maleate sustained-release floating microspheres for improved bioavailability.

The object of this study was to prepare rosiglitazone maleate (RM) sustained-release floating microspheres and investigate their pharmacokinetics. RM microspheres were prepared with ethyl cellulose (EC) and octadecyl alcohol as the carrier materials by an emulsion-solvent diffusion method, and the properties of morphology in vitro floating capability, drug loading (DL), entrapment efficiency (EE), in vitro release and in vivo pharmacokinetics were investigated. The prepared microspheres had a completely spherical shape. The percentage of microspheres floating after 12 h was (91.45 +/- 1.62)%, and the DL and EE were (9.31 +/- 0.31)% and (89.55 +/- 1.65)% respectively. Pharmacokinetic studies demonstrated that the RM floating microspheres were superior to commercial tablets in terms of the decrease in peak plasma concentration and maintenance of RM concentration in plasma. The area under the curve of plasma concentration-time (AUC) of the floating microspheres was equivalent to that of reference tablets. The results showed that floating microspheres are a feasible approach for the sustained-release preparation of drugs which have limited absorption sites in the upper small intestine.

Preparation and enhanced oral bioavailability of cryptotanshinone-loaded solid lipid nanoparticles.

In this study, solid lipid nanoparticles (SLNs) were successfully prepared by an ultrasonic and high-pressure homogenization method to improve the oral bioavailability of the poorly water-soluble drug cryptotanshinone (CTS). The particle size and distribution, drug loading capacity, drug entrapment efficiency, zeta potential, and long-term physical stability of the SLNs were characterized in detail. A pharmacokinetic study was conducted in rats after oral administration of CTS in different SLNs, and it was found that the relative bioavailability of CTS in the SLNs was significantly increased compared with that of a CTS-suspension. The incorporation of CTS in SLNs also markedly changes the metabolism behavior of CTS to tanshinone IIA. These results indicate that CTS absorption is enhanced significantly by employing SLN formulations, and SLNs represent a powerful approach for improving the oral absorption of poorly soluble drugs.

[Apoptosis in detached corn root cap cells under fluorescent microscope].

Apoptosis in detached corn root cap cells under fluorescent microscope was studied. Homokaryon maize B37 inbred lines was tested and the detached corn root cap cells with cell wall might be stained using Hoechst33342. Apoptosis was found under fluorescence microscope treated by culture filtrate of HMC toxin. The sensitivity of HMC toxin to C cytoplasm was greater than N cytoplasm and there was more resistance response in detached corn root cap cells of N cytoplasm than C cytoplasm. Besides, apoptosis did not coincide at different processing times. These indicated that special disease response occurred in the course of apoptosis in detached corn root cap cells of C cytoplasm maize led by HMC which may be collective result of nucleus and cytoplasm.