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Bacterial wound infection has emerged as a pivotal threat to human health worldwide, and the situation has worsened owing to the gradual increase in antibiotic‐resistant bacteria caused by the improper use of antibiotics. To reduce the use of antibiotics and avoid the increase in antibiotic‐resistant bacteria, researchers are increasingly paying attention to photodynamic therapy, which uses light to produce reactive oxygen species to kill bacteria. Treating bacteria‐infected wounds by photodynamic therapy requires fixing the photosensitizer (PS) at the wound site and maintaining a certain level of wound humidity. Hydrogels are materials with a high water content and are well suited for fixing PSs at wound sites for antibacterial photodynamic therapy. Therefore, hydrogels are often loaded with PSs for treating bacteria‐infected wounds via antibacterial photodynamic therapy. In this review, we systematically summarised the antibacterial mechanisms and applications of PS‐loaded hydrogels for treating bacteria‐infected wounds via photodynamic therapy. In addition, the recent studies and the research status progresses of novel antibacterial hydrogels are discussed. Finally, the challenges and future prospects of PS‐loaded hydrogels are reviewed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence of falls in elderly aged 65 years and above among outpatients and inpatients, and to analyze its related factors and identify prevention strategies. Methods: A retrospective analysis was conducted on 451 patients aged 65 years and above who received comprehensive geriatric assessment in outpatients and inpatients from the Department of Geriatrics in the Second Xiangya Hospital from March 2021 to March 2022. According to whether there had been at least one fall in the past year, the patients were divided into a fall group and a non‐fall group. Data were collected from the We‐Chat applet of comprehensive geriatric assessment. A t test and chi‐square test were performed to compare the difference between the two groups. Logistic regression analysis was then conducted to identify factors associated with falls. Results: (1) The incidence of falls among the outpatient and inpatient was 28.8%. (2) The rate of light, moderate, and heavy dependence on daily living ability and decreased mobile balance ability were higher in the fall group than those in the non‐fall group. The average calf circumference in the fall group was significantly lower than that in the non‐fall group. (3) The prevalence of diabetes and eye diseases in the fall group was significantly higher than that in the non‐fall group. (4) The percentage of insomnia and suspicious insomnia cases in the fall group was higher than that in the non‐fall group. The mean scores for dysphagia, frailty, and incontinence were higher and the mean malnutrition score was lower in the fall group than in the non‐fall group. (5) Multiple logistic regression analysis showed that frailty, insomnia, and malnutrition were independent influencing factors of fall (OR = 1.955, 1.652, 10.719, P = 0.044, 0.041, 0.025, respectively). Conclusions: The incidence of falls among outpatients and inpatients aged 65 years and above is high. Frailty, insomnia, and malnutrition are the main factors influencing falls in these patients. [ABSTRACT FROM AUTHOR]

Au-Fe3O4 nanoparticles were widely used as nanoplatforms for biologic applications through readily further functionalization. Dopamine (DA)-coated superparamagnetic iron oxide (SPIO) nanoparticles (DA@Fe3O4) have been successfully synthesized using a one-step process by modified coprecipitation method. Then 2-3 nm gold nanoparticles were easily conjugated to DA@Fe3O4 nanoparticles by the electrostatic force between gold nanoparticles and amino groups of dopamine to afford water-soluble Au-Fe3O4 hybrid nanoparticles. A detailed investigation by dynamic light scatting (DLS), transmission electron microscopy (TEM), fourier transform infrared (FT-IR) and X-ray diffraction (XRD) were performed in order to characterize the physicochemical properties of the hybrid nanoparticles. The hybrid nanoparticles were easily functionalized with a targeted small peptide A54 (AGKGTPSLETTP) and fluorescence probe fluorescein isothiocyanate (FITC) for liver cancer cell BEL-7402 imaging. This simple approach to prepare hybrid nanoparticles provides a facile nanoplatform for muti-functional derivations and may be extended to the immobilization of other metals or bimolecular on SPIO surface. [ABSTRACT FROM AUTHOR]

A one-pot synthesis of new oxindole-fused polycyclic scaffolds is reported. The process involves a three-component [3+2] cycloaddition followed by cyclization through an intramolecular Michael addition. The reaction gives easy access to oxindole-fused spirotetrahydrofurochromans in moderate to good yields with high regio- and diastereoselectivity. These compounds could be useful for for drug discovery. Further modification was achieved by reduction of the nitro group, and intramolecular amide formation to give the corresponding lactams. The resulting heterocyclic products show good inhibitory activity against the enzyme PTP1B in vitro. [ABSTRACT FROM AUTHOR]

The chiral RhI-diene-catalyzed asymmetric three-component reaction of aryldiazoacetates, aromatic amines, and β-nitroacrylates was achieved to obtain γ-nitro-α-amino-succinates in good yields and with high diastereo- and enantioselectivity. This reaction is proposed to proceed through the enantioselective trapping of RhI-associated ammonium ylides by nitroacrylates. This new transformation represents the first example of RhI-carbene-induced ylide transformation. [ABSTRACT FROM AUTHOR]

An elegant synergistic catalytic system comprising a ruthenium complex with a chiral Brønsted acid was developed for a four-component Mannich/cascade aza-Michael reaction. The ruthenium-associated ammonium ylides successfully trapped with in situ generated imines indicates a stepwise process of proton transfer in the ruthenium-catalyzed carbenoid NH insertion reaction. The different decomposition abilities of various ruthenium complexes towards diazo compounds were well explained by the calculated thermodynamic data. The transformation features a mild, rapid, and efficient method for the synthesis of enantiomerically pure 1,3,4-tetrasubstituted tetrahydroquinolines bearing a quaternary stereogenic carbon center from simple starting precursors in moderate yields with high diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

Trapped: A Michael‐aldol‐type cascade reaction including the trapping of an oxonium ylide through a delayed proton shift leads to the formation of multiple stereocenters in a mild one‐pot synthesis. Enantiomerically pure indanol derivatives with four stereocenters and a stereogenic quaternary carbon center were easily obtained through this method in moderate to good yields. [ABSTRACT FROM AUTHOR]

Gold nanoshells have shown a great potential for use as agents in a wide variety of biomedical applications, and some of which require the delivery of large numbers of gold nanoshells onto or into the cells. Here, we develop a ready method to enhance the cellular uptake of gold nanoshells by modifying with meso-2,3-dimercaptosuccinic acid (DMSA). The quantifiable technique of inductively coupled plasma atomic emissions spectroscopy (ICP-AES) and transmission electron microscopy (TEM) were used to investigate the cellular uptake of unmodified and DMSA-modified gold nanoshells. Three cell lines (RAW 264.7, A549, and BEL-7402) were involved and the results indicated that the cellular uptake of the DMSA-modified gold nanoshells was obviously enhanced versus the unmodified gold nanoshells. The reason possibly lies in the nonspecific adsorption of serum protein on the DMSA-modified gold nanoshells (DMSA-GNs), which consequently enhanced the cellular uptake. As a continued effort, in vitro experiments with endocytic inhibitors suggested the DMSA-GNs internalized into cells via receptor-mediated endocytosis (RME) pathway. This study has provided a valuable insight into the effects of surface modification on cellular uptake of nanoparticles. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the stability and activity of α-chymotrypsin (CT) that has been immobilized on carboxyl-functionalized magnetic nanogels. Under the study, the impact of protease and surfactants on enzyme stability and the catalytic activity of the immobilized enzyme with regard to protein substrate have been determined. Findings indicate that CT sustained activity despite immobilization. The stability of CT is associated with the structural rigidity of the enzyme.

The article presents chemical equations related to the article on the synthesis of Aryl Serine derivatives by C. Wang and colleagues, published in the "Tetrahedron" in 2013.

The article mentions the advancement of chiral bronsted acids as cooperative catalysts for multicomponent and cascade reactions, published in the 2013 issue of "Asian Journal of Organic Chemistry."

Ammonium ylides generated in situ from aryldiazo acetates and arylamines undergo Mannich-type reaction with N-sulfonyl aldimines to produce α,β-diamino acid derivatives. [ABSTRACT FROM AUTHOR]