Colorimetric screening model for identification of menaquinone-7 (MK-7) producing strains.

In this study, a novel colorimetric screening method for identifying menaquinone-7 (MK-7) producing strains was established using potassium permanganate. To our knowledge, this method represents the first direct screening methodology for the identification of MK-7 producing strains. Utilizing this screening method, a new MK-7 producing strain, Bacillus subtilis GSA-184, was identified from the soil of the Tibetan Plateau. Under the optimized fermentation medium (50 g/L glycerol, 30 g/L yeast extract powder, 100 g/L soybean peptone, 1 g/L KH2PO4, and 1 g/L MnSO4), the production of MK-7 was increased to 25.7 mg/L. Additionally, the maximum production of MK-7 reached 36.46 mg/L after 48 h in a 5-L fermenter. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04097-1.

Discovery of a cinnamyl piperidine derivative as new neddylation inhibitor for gastric cancer treatment.

Targeting neddylation pathway has been recognized as an attractive anticancer therapeutic strategy, thus discovering potent and selective neddylation inhibitors is highly desirable. Our work reported the discovery of novel cinnamyl piperidine compounds and their antitumor activity in vitro and in vivo. Among these compounds, compound 4g was identified as a novel neddylation inhibitor and decreased the neddylation levels of cullin 1, cullin 3 and cullin 5. Mechanistic studies demonstrated that compound 4g could inhibit the migration ability of gastric cancer cells and induce apoptosis partly mediated by the Nrf2-Keap1 pathway. Furthermore, in vivo anti-tumor studies showed that 4g effectively inhibited tumor growth without obvious toxicity. Collectively, the cinnamyl piperidine derivatives could serve as new lead compounds for developing highly effective neddylation inhibitors for gastric cancer therapy.

Industrial kinetic resolution of d,l-pantolactone by an immobilized whole-cell biocatalyst.

Immobilized whole-cells of Pichia pastoris harboring recombinant d-lactonase were entrapped in calcium alginate gels and used as an efficient biocatalyst for catalytic kinetic resolution of d,l-pantolactone. The immobilized whole-cell biocatalyst exhibited good catalytic stability, which was applied for stereospecific hydrolysis of d-pantolactone for up to 56 repeated batch reactions without obvious loss in the catalytic activity and enantioselectivity.

Serum Antibody and Glomerular Antigen of Antiphospholipase A2 Receptor in Chinese Patients with Idiopathic Membranous Nephropathy.

BACKGROUND: M-type phospholipase A2 receptor (PLA2R) is the first autoantigen responsible for idiopathic membranous nephropathy (IMN). However, serum PLA2R antibody (PLA2R-Ab) can be inaccurate in distinguishing between IMN and secondary membranous nephropathy, while renal PLA2R antigen (PLA2R-Ag) emerges as an ancillary diagnostic. The present study is aimed at examining the associations between PLA2R-Ab in sera and PLA2R-Ag in kidneys in IMN patients. METHODS: A total of 93 patients with IMN were retrospectively identified. Their serum PLA2R-Ab and renal PLA2R-Ag expression levels were determined, and the clinical correlations between these parameters and clinical features were examined. RESULTS: The sensitivities of serum PLA2R-Ab and renal PLA2R-Ag for diagnosing IMN were 74.2% and 88.2%, respectively (P < 0.001), with poor consistency. Higher serum PLA2R-Ab levels were correlated to stronger renal PLA2R-Ag expression (P = 0.048). Patients with positive PLA2R-Ab significantly differed from those with negative levels, in terms of proteinuric levels over 24 hours (4.54 vs. 3.46 g/day, P = 0.015) and serum albumin (23.28 vs. 27.95 g/L, P = 0.038). Among patients with positive renal PLA2R-Ag, patients with positive PLA2R-Ab had significantly higher 24-hour proteinuria, when compared to patients with negative PLA2R-Ab (4.57 vs. 3.08 g/day, P = 0.005). Among those with positive PLA2R-Ab in sera, their PLA2R-Ab levels were correlated with the estimated glomerular filtration and serum creatinine. CONCLUSION: Serum PLA2R-Ab exhibits a closer correlation with proteinuric severity and renal function, when compared to renal PLA2R-Ag.

Biocatalytic kinetic resolution of d,l-pantolactone by using a novel recombinant d-lactonase.

d-Pantolactone is a key chiral intermediate for the synthesis of d-pantothenic acid and its derivatives. Biocatalytic kinetic resolution of d,l-pantoyl lactone using d-lactonase is an efficient route to synthesize d-pantolactone. In this study, we report the expression of a novel d-lactonase TSDL in Escherichia coli host. The recombinant TSDL exhibited high hydrolysis activity and enantioselectivity toward d-pantolactone. The reaction conditions of the recombinant TSDL-catalyzed kinetic resolution of d,l-pantolactone was systematically investigated by whole cell biocatalysis. In addition, a preparative-scale reaction for bioproduction of d-pantoic acid was examined under optimized reaction conditions. This study presented an alternative enzymatic process for kinetic resolution of d,l-pantolactone.

Nimodipine rescues N-methyl-N-nitrosourea-induced retinal degeneration in rats.

BACKGROUND: That nimodipine (NMD) is potentially useful for ophthalmic treatment. However, the effect of NMD is unknown on retinal degenerative diseases. OBJECTIVE: The purpose of the present study was to investigate the effect of NMD on N-methyl-N-nitrosourea (MNU)-induced retinal degeneration (RD) and elucidate its possible mechanisms. MATERIALS AND METHODS: Morphological observation of NMD on MNU-induced RD was evaluated by light microscopy and electron microscopy. Nonenzymatic antioxidant glutathione (GSH) was measured by a colorimetric method. Transforming growth factor-beta (TGF-ß) was measured by enzyme-linked immunosorbent assay (ELISA). Telomerase was detected by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The significantly protective effect of NMD on MNU-induced RD was demonstrated morphologically. NMD increased the content of GSH and decreased the level of TGF-ß in rat retina. RT-PCR analysis demonstrated that NMD treatment significantly decreased mRNA level of telomerase. CONCLUSION: These data suggest that NMD inhibit MNU-induced RD in rats. The expressions of TGF-ß, telomerase and GSH contents might partially contribute to its protective effects on MNU-induced RD.

Reduction of cyclophosphamide-induced DNA damage and apoptosis effects of ginsenoside Rb(1) on mouse bone marrow cells and peripheral blood leukocytes.

The present study investigated the protective effects of ginsenoside Rb(1) (GRb(1)) against genotoxicity induced by cyclophosphamide (CP). Single cell gel electrophoresis, flow cytometry assay with annexin V-FITC/propidine iodide (PI) and acridine orange (AO)/ethidium bromide (EB) staining assay were employed to measure DNA damage and cell apoptosis, respectively. The activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GPx) and the malondialdehyde (MDA) content were also investigated by a number of colormetric methods. The results showed that the CP produced significant DNA damage and cell apoptosis in mouse bone marrow cells or peripheral blood leukocytes, markedly inhibited the activities of T-SOD and GPx, and markedly increased the MDA content. GRb(1) significantly inhibited DNA damages and cell apoptosis in mouse bone marrow cells or peripheral blood leukocytes induced by CP and antagonized the reduction of CP-induced T-SOD and GPx activities, and inhibited the increase in MDA content induced by CP. The anti-tumor study of GRb(1) showed that GRb(1) did not affect the anti-tumor activities of CP. In conclusion, GRb(1) had significant protective effects against DNA damage and apoptosis induced by CP.

Protective effects of ginsenoside Rg(3) against cyclophosphamide-induced DNA damage and cell apoptosis in mice.

Despite the significant anti-tumor activities, cyclophosphamide (CP) also shows cytotoxicity to normal cells. In order to explore the protective effects of drugs against CP-induced adverse effects, 20(S)-ginsenoside Rg(3) was tested for its possibly protective activities on CP-induced DNA damage and cell apoptosis in mouse bone marrow cells or peripheral lymphocyte cells. In the current study, the alkaline single cell gel electrophoresis (comet assay), flow cytometry assay with annexin V-FITC/PI and AO/EB staining assay were employed to measure DNA strand breakage and cell apoptosis, respectively. The activities of SOD and GPx and the contents of MDA were also tested by the various colormetric methods. The results showed that CP at a dose of 100 mg/kg, i.p. significantly caused DNA damages in both mouse bone marrow cells and peripheral lymphocyte cells, and markedly inhibited the activities of GPx and SOD and increased MDA contents in mouse blood. Moreover, CP at a dose of 200 mg/kg, i.p. triggered apoptosis in mouse bone marrow cells. On the other hand, 20(S)-ginsenoside Rg(3) orally administered at a dose of 20 mg/kg to the animals once a day for 2 days significantly inhibited CP-induced DNA damages in mouse bone marrow cells and peripheral lymphocyte cells, decrease the apoptotic numbers of bone marrow cells, antagonized the reduction of the activities of SOD and GPx, and the increase in MDA contents. In conclusion, 20(S)-ginsenoside Rg(3) showed the significant protective effects on CP-induced cell DNA damage and apoptosis. These effects might be partially attributed to its protective actions against CP-induced oxidative stress.

Protective effects of total saponins from stem and leaf of Panax ginseng against cyclophosphamide-induced genotoxicity and apoptosis in mouse bone marrow cells and peripheral lymphocyte cells.

BACKGROUND: Cyclophosphamide (CP), commonly used anti-cancer, induces oxidative stress and is cytotoxic to normal cells. It is very important to choice the protective agent combined CP to reduce the side effects in cancer treatment. Ginsenosides are biological active constituents of Panax ginseng C.A. Meyer that acts as the tonic agent for the cancer patients to reduce the side effects in the clinic application. Because CP is a pro-oxidant agent and induces oxidative stress by the generation of free radicals to decrease the activities of anti-oxidant enzymes, the protective effects of the total saponins from stem and leaf of P. ginseng C.A. Meyer (TSPG) act as an anti-oxidant agent against the decreased anti-oxidant enzymes, the genotoxicity and apoptosis induced by CP was carried out. METHODS: The alkaline single cell gel electrophoresis was employed to detect DNA damage; flow cytometry assay and AO/EB staining assay were employed to measure cell apoptosis; the enzymatic anti-oxidants (T-SOD, CAT and GPx) and non-enzymatic anti-oxidant (GSH) were measured by the various colorimetric methods. RESULTS: CP induced the significant DNA damage in mouse peripheral lymphocytes in time- and dose-dependent manners, inhibited the activities of T-SOD, GPx and CAT, and decreased the contents of GSH in mouse blood, triggered bone marrow cell apoptosis at 6 and 12h. TSPG significantly reduced CP-induced DNA damages in bone marrow cells and peripheral lymphocyte cells, antagonized CP-induced reduction of T-SOD, GPx, CAT activities and the GSH contents, decreased the bone marrow cell apoptosis induced by CP. CONCLUSIONS: TSPG, significantly reduced the genotoxicity of CP in bone marrow cells and peripheral lymphocyte cells, and decreased the apoptotic cell number induced by CP in bone marrow cells. The effects of TSPG on T-SOD, GPx, CAT activities and GSH contents might partially contribute to its protective effects on CP-induced cell toxicities.

[Application of Edgewise appliance for fixation of dislocated permanent anterior teeth caused by trauma].

PURPOSE: To evaluate the clinical effect of edgewise appliance in the fixation of dislocated permanent anterior teeth caused by trauma. METHODS: 69 traumatically avulsed teeth without fracture in 37 patients were treated by fixing the teeth with Edgewise appliance. There were three kinds of dislocated permanent anterior teeth: half dislocated teeth, complete dislocated teeth and embedding avulsed teeth. The half dislocated teeth were gently reset instead of violence and fixed for 2-4 weeks or so. The complete dislocated teeth were replanted after the traumatic teeth and alveolus dens were appropriately treated and fixed for 4-6 weeks or so, the last kind of teeth with definitive dental root could be gently drew, reset and fixed with Edgewise appliance in which traction curve was added to. The embedding or traumatic avulsed teeth were appropriately fixed for 6-8 weeks. RESULTS: Patients were followed up for 3 years. Among the 69 traumatic teeth treated with Edgewise appliance, the treatment result was excellent in 32 teeth, fair in 35 teeth, failed in 2 teeth. The overall effective rate was 97.10%. CONCLUSIONS: Edgewise appliance is safe, effective, and feasible for patients with traumatically dislocated permanent anterior teeth.