Antibacterial black phosphorus nanosheets for biomedical applications.

Bacterial infections pose a significant threat to human health and a heavy burden on the global healthcare system. Antibiotics are the primary treatment, but they can lead to bacterial resistance and adverse side effects. Two-dimensional (2D) nanomaterials such as graphene, MoS2, and MXene have emerged as novel antibacterial agents due to their potential to circumvent bacterial resistance. Among the 2D nanomaterials, black phosphorus nanosheets (BPNs) have attracted great research interest due to their excellent biocompatibility. BPNs possess unique properties, such as a high specific surface area, tunable bandgap, and easy surface functionalization, enabling them to combat bacteria through physical disruption of bacterial membranes, photothermal and photodynamic therapies. However, the low preparation efficiency and inevitable oxidative degradation of BPNs have limited their wide application. This review provides a comprehensive overview of recent advances in antibacterial research on BPNs, encompassing their preparation methods, structural and physicochemical properties, antibacterial mechanisms, and potential applications. By addressing the challenges and prospects of using BPNs as an alternative to antibiotics, this review provides valuable insights and guidance for utilizing BPNs in shaping the future of antibacterial therapy.

Jinhua Qinggan granules attenuates acute lung injury by promotion of neutrophil apoptosis and inhibition of TLR4/MyD88/NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Acute lung injury (ALI) is one of the fatal complications of respiratory virus infections such as influenza virus and coronavirus, which has high clinical morbidity and mortality. Jinhua Qinggan granules (JHQG) has been approved by China Food and Drug Administration in the treatment of H1N1 influenza and mild or moderate novel coronavirus disease 2019 (COVID-19), which is an herbal formula developed based on Maxingshigan decoction and Yinqiao powder that have been used to respiratory diseases in China for thousands of years. However, the underlying mechanism of JHQG in treating infectious diseases remains unclear. AIM OF THE STUDY: This study investigated the effects of JHQG on neutrophil apoptosis and key signaling pathways in lipopolysaccharide (LPS) -induced ALI mice in order to explore its mechanism of anti-inflammation. MATERIALS AND METHODS: The effect of JHQG on survival rate was observed in septic mouse model by intraperitoneal injection of LPS (20 mg/kg). To better pharmacological evaluation, the mice received an intratracheal injection of 5 mg/kg LPS. Lung histopathological changes, wet-to-dry ratio of the lungs, and MPO activity in the lungs and total protein concentration, total cells number, TNF-α, IL-1ß, IL-6, and MIP-2 levels in BALF were assessed. Neutrophil apoptosis rate was detected by Ly6G-APC/Annexin V-FITC staining. Key proteins associated with apoptosis including caspase 3/7 activity, Bcl-xL and Mcl-1 were measured by flow cytometry and confocal microscope, respectively. TLR4 receptor and its downstream signaling were analyzed by Western blot assay and immunofluorescence, respectively. RESULTS: JHQG treatment at either 6 or 12 g/kg/day resulted in 20% increase of survival in 20 mg/kg LPS-induced mice. In the model of 5 mg/kg LPS-induced mice, JHQG obviously decreased the total protein concentration in BALF, wet-to-dry ratio of the lungs, and lung histological damage. It also attenuated the MPO activity and the proportion of Ly6G staining positive neutrophils in the lungs, as well as the MIP-2 levels in BALF were reduced. JHQG inhibited the expression of Mcl-1 and Bcl-xL and enhanced caspase-3/7 activity, indicating that JHQG partially acted in promoting neutrophil apoptosis via intrinsic mitochondrial apoptotic pathway. The levels of TNF-α, IL-1ß, and IL-6 were significantly declined in LPS-induced mice treated with JHQG. Furthermore, JHQG reduced the protein expression of TLR4, MyD88, p-p65 and the proportion of nuclei p65, suggesting that JHQG treatment inhibited TLR4/MyD88/NF-κB pathway. CONCLUSION: JHQG reduced pulmonary inflammation and protected mice from LPS-induced ALI by promoting neutrophil apoptosis and inhibition of TLR4/MyD88/NF-κB pathway, suggesting that JHQG may be a promising drug for treatment of ALI.

Highly Stretchable and Conductive Self-Healing Hydrogels for Temperature and Strain Sensing and Chronic Wound Treatment.

Flexible bioelectronics for biomedical applications requires a stretchable, conductive, self-healable, and biocompatible material that can be obtained by cost-effective chemicals and strategies. Herein, we synthesized polypyrrole or Zn-functionalized chitosan molecules, which are cross-linked with poly(vinyl alcohol) to form a hydrogel through dynamic di-diol complexations, hydrogen bonding, and zinc-based coordination bonds. These multiple dynamic interactions endow the material with excellent stretchability and autonomous self-healing ability. The choice of Food and Drug Administration (FDA)-approved materials (poly(vinyl alcohol) and chitosan) as the matrix materials ensures the good biocompatibility of the hydrogel. The conductivity contributed by the polypyrrole allowed the hydrogel to sense strain and temperature, and the coordinated Zn significantly enhanced the antibacterial activity of the hydrogel. Moreover, using a diabetic rat model, we have proved that this hydrogel is capable of promoting the healing of the infected chronic wounds with electrical stimulation.

Preparation and application of polyvinyl alcohol-decorated cell membrane chromatography for screening anti-osteoporosis components from Liuwei Dihuang decoction-containing serum.

Cell membrane chromatography is a powerful tool for screening active components from complex matrices. New cell membrane carriers need to be developed to increase the coverage of cell membranes on the surface of stationary phases, thereby improving cell membrane chromatographic retention. In this work, we prepared polyvinyl alcohol-poly dimethyl diallyl ammonium chloride modified silica gel as a cell membrane carrier. Osteoblast cell was used as cell membrane source, which was widely used to evaluate the osteogenic activity of drugs. The new cell membrane chromatographic stationary phase was used to screen anti-osteoporosis components in Liuwei Dihuang decoction-containing serum. The chemical structures of the new modified materials were characterized by scanning electronic microscopy, Fourier transform infrared spectroscopy, and elemental analysis characterization. Compared with the common cell membrane column, the cell membrane coverage of this modified material was increased by 30%, and thus provided a stronger retention effect in positive drugs. Nineteen metabolites in rat serum samples were retained on the cell membrane chromatography and identified by ultra-high-performance liquid chromatography/time-of-flight mass spectrometry. Among those, four components (morroniside, catalpol, loganin, and acteoside) were selected for in vitro pharmacodynamics validation. They significantly increased the osteoblast proliferation. The new modified material was successfully applied to screen anti-osteoporosis components from Liuwei Dihuang Decoction-containing serum.

Co-assembled supramolecular hydrogels of cell adhesive peptide and alginate for rapid hemostasis and efficacious wound healing.

Injectable hydrogels are promising materials for applications in non-compressive wound management. Yet difficulties remain for the fabrication of mechanically stable hydrogel materials with inherent functionalities in both hemostatic control and wound healing without additional supplements of growth factors. Herein, we reported the co-assembly of a cell adhesive peptide conjugate (Pept-1) and alginate (ALG), to confer supramolecular hydrogels with excellent mechanical properties and high efficacy in both hemostatic control and wound healing requiring no additional growth factors. The co-assembling process of Pept-1 and ALG, which was mediated by electrostatic interactions and metal chelation, afforded a composite hydrogel with denser nanofibrillar structures and better mechanical strength when comparing to the Pept-1 gel alone. As-prepared Pept-1/ALG hydrogels exhibited excellent injectability and thixotropic properties, making them ideal materials for wound dressing. The composite hydrogel induced fast hemostasis when spiked with whole blood in vitro, and reduced the amount of bleeding to ∼18% of the untreated control in a liver puncture mouse model. Meanwhile, it promoted adhesion and migration of fibroblast NIH3T3 cells in vitro, and accelerated the rate of wound healing in a full-thickness skin defect model of mice. In addition, the Pept-1/ALG hydrogel showed excellent biocompatibility with no obvious hemolytic activity. In future, the strategy of utilizing co-assembled nanostructures composed of biofunctional peptides and polysaccharides could be further exploited to construct a broad range of nanocomposite materials for a variety of biomedical applications.

[Rapid screening of anti-osteoporosis active ingredients from Liuwei Dihuang Decoction by osteoblast membrane chromatography/ultra-high performance liquid chromatography-time of flight mass spectrometry].

A method was established for determination of potential anti-osteoporosis ingredients from Liuwei Dihuang Decoction by osteoblast cell membrane chromatography/ultra-performance liquid chromatography/time-of-flight mass spectrometry (CMC/UPLC-TOF/MS). The osteoblasts were used as the source of cell membrane for the preparation of CMC stationary phase. An osteoblast CMC column (10 mm×2 mm) was prepared by coating silica gel (0.05 g) with cell membrane. The active ingredients in the aqueous extract of Liuwei Dihuang Decoction (90 g/L) were first screened by CMC. Water was used as the mobile phase, and the flow rate was 0.20 mL/min. Then, the eluates of the CMC were qualitatively analyzed by UPLC-TOF/MS using a WATERS ACQUITY UPLC BEH C18 column (10 mm×2 mm). Acetonitrile-water was used as the mobile phase at a flow rate of 0.40 mL/min. This method could quickly and selectively identify 16 potential anti-osteoporotic active ingredients from Liuwei Dihuang Decoction. Due to high catalpol content in Liuwei Dihuang Decoction and its good affinity with CMC column, catapol was selected for in vivo and in vitro pharmacological examinations. It was found that catalpol (1-10 µmol/L) could significantly promote the proliferation of osteoblasts in a dose-dependent manner. It also significantly increased the area of bone staining in osteoporosis zebrafish model. The osteoblast CMC/UPLC-TOF/MS method could quickly screen the anti-osteoporosis active ingredients in complex traditional Chinese medicine prescriptions, and had the advantages of simple operation, high efficiency and high sensitivity.

Preparation of micro-cell membrane chromatographic columns with polyvinyl alcohol-modified polyether ether ketone tube as cellular membrane carrier.

Cell membrane chromatography is a promising technique for screening active components from complex matrices. Unfortunately, the large consumption of cells and low resolutions of analytes limit the applications of this method. Herein, we report polyether ether ketone tube as a novel cellular membrane carrier for cell membrane chromatography. Its inner surface is firstly coated by polyvinyl alcohol and then cell membranes are physically adsorbed onto the polyvinyl alcohol layer. To verify this approach, osteoclast and osteoblast micro-column were prepared and characterized by calcitonin and verapamil, respectively. Comparing with common cell membrane chromatographic column, the micro-cell membrane chromatographic columns showed about 1000-fold decrease of cell consumption and satisfactory retention behavior. The developed column was applied to screen potential active components from Cortex Phellodendri Chinensis. A total of 18 components in Cortex Phellodendri Chinensis extract were observed as having retention property of osteoclast micro-cell membrane chromatographic column, while 10 components retained on osteoblast micro-cell membrane chromatographic column. The results of in vitro assay showed that berberine, obacunoic acid and phellodendrine had an obvious inhibitory effect on osteoclast differentiation and function. Berberine and tetrahydropalmatine increased the osteoblast proliferations and mineralized nodules density. This cell membrane/polyvinyl alcohol column can be applied to various biological chromatography models.

Chemical constituents of Pholidota cantonensis.

Two 9,10-dihydrophenanthrenes trivially named phocantol and phocantone, two diterpenoid glycosidesnamed phocantoside A and phocantoside B were isolated from the ethanol extract of the air-dried whole plant of Pholidota cantonensis Rolfe, together with seventeen known compounds. The structures of the four compounds were identified as 1-hydroxy-2,7-dimethoxy-9,10-dihydrophenanthro-[4,5-bcd]furan, 5-hydroxy-2,7-dimethoxy-9,10-dihydro-1,4-phenanthrenedione, (8R,13E)-ent-labd-13-ene-3α,8,15-triol 15-O-ß-D-gluco-pyranoside and (5S,8R,9S,10R)-cis-cleroda-3,13(E)-diene-15,18-diol 15-O-ß-D-glucopyranosyl-18-O-ß-D-glucopyranoside by chemical and spectroscopic methods, including 1D and 2D NMR. Twenty compounds were evaluated for their cytotoxic activities against mouse leukemia p388D1 cancer cells, and compound phocantone, phocantoside A, tanshinone IIA and syringate exhibited cytotoxic activity against the mouse leukemia p388D1 cancer cells with IC50 values ranging from 13.37 to 27.5 µM.

[Effect of Jiangang Yishen Recipe on high insulin induced cell proliferation of human glomerular mesangial cells and the expression of insulin receptor substrate 1 and phosphatidylinositol-3-kinase].

OBJECTIVE: To investigate the effect of Jiangtang Yishen Recipe (JTYSR) on high insulin induced cell proliferation of human glomerular mesangial cells (HMCs) and the expression of insulin receptor substrate 1 (IRS-1) and phosphatidylinositol-3-kinase (PI-3K). METHODS: HMCs were divided into 4 groups, i.e., the negative control group, the high insulin model group, the JTYSR group, and the LY294002 group. The concentration of insulin, JTYSR, and LY294002 was respectively confirmed by pre-experiment. Different culture solution was respectively added for different groups. RPMI1640 culture solution was added for HMCs in the negative control group, while HMCs in the rest 3 groups were cultured by 100 nmol/L insulin for 24 h. Meanwhile, HMCs from the JTYSR group and the LY294002 group were exposed to 125 mg/L JTYSR and 80 micromol/L LY294002 respectively for further 48 h. The proliferation of HMCs was detected by MTT and flow cytometry. The protein expression of IRS-1 and PI-3K in HMC was detected by immunohistochemical assay and Western blot. Results The proliferation of HMCs induced by high insulin could be significantly lowered, and the protein expression of IRS-1 and PI-3K could be down-regulated in the JTYSR group and the LY294002 group (P <0.01). Compared with the LY294002 group, the protein expression of IRS-1 and PI-3K could be slightly down-regulated in the JTYSR group (P <0.05). CONCLUSION: JTYSR could lower high insulin induced proliferation of HMCs, and its mechanism might be related to insulin signaling pathway.

[Chemical constituents of Gentiana rhodantha].

OBJECTIVE: To determine the chemical constituents of Gentiana rhodantha. METHOD: To isolate the constituents, column chromatography over silica gel, MCI, Sephadex LH-20 and C18 reverse-phased silica gel were used. Spectroscopic methods were used to elucidate the structures of the isolated compounds. RESULT: Sixteen compounds were isolated and elucidated as ten phonemic compounds, namely 1,3,7,8-tetrahydroxylxanthone (1), rhodanthenone D (2), 1,3,6,7-tetrahydroxylxanthone (3), 1,3,7-trihydroxy-4,8-dimethoxyxanthone (4), quercetin (5), isoorientin (6), mangiferin (7), norswertianolin (8), gallic acid ethyl ester (9) and salicylic acid (10), and six triterpenes including alpha-amyrin (11), erythrodiol 3-O-palmitate (12), ursolic aldehyde (13), uvaol 3-O-acetyl (14), ursolic acid (15) and 2alpha-hydroxyursolic acid (16). CONCLUSION: Compounds 4-6, 8, 10-12, 15 and 16 were isolated from this plant for the first time. Compounds 1 and 3 were obtained firstly from the genus Gentiana and compounds 9, 13-14 were firstly from the family Gentianaceae.

Effects of QWBZP on T-cell subsets and their cytokines in intestinal mucosa of HRV infection suckling mice.

AIM OF THIS STUDY: Qiwei Baizhu Powder (QWBZP) is a traditional herbal prescription that has been used traditionally for the treatment of infantile diarrhea, including the infantile diarrhea caused by Human Rotavirus (HRV). In this study, we investigated the pharmacological activity of QWBZP extract. MATERIALS AND METHODS: NIH suckling mice with HRV induced diarrhea were used. Density of CD3(+), CD4(+) and CD8(+) T cells, mRNA expression of IL-2, IFN-gamma, IL-4 and IL-10 in intestinal mucosa epithelial cells were assayed. RESULTS: QWBZP extract promoted the expressions of mRNA of IL-2, IL-4, IL-10 and IFN-gamma in intestinal mucosa epithelial cells. Also, we found that the density of CD8(+) cells in intestinal mucosa epithelial cells was significantly lower in QWBZP group than in Model group, while the density of CD8(+) cells was significantly higher in QWBZP group than in Model group. CONCLUSION: These data suggest that QWBZP extract may exhibit antiviral effects through modulating the densities of T-cell subsets and the expressions of their cytokines in small intestinal mucosa epithelial cells.

[Experimental research of songzhi pills on inducement of interferon in mice and rats].

OBJECTIVE: To develop a new drug of treating the hepatitis C virus by studing the mechanisms of songzhi pills. METHOD: The four-wee old mice and two-month old rats were chosen to induce interferon. RESULT: The contents of interferon among the groups treated with songzhi pills were significantly higher than those of the normal group and the model group (P < 0.01), CONCLUSIONS: Songzhi pills may have the function of inducing interferon.