[Systematic analysis on chemical constituents of Mori Cortex, mulberry root bark and its phellem layer based on HPLC-ESI-MS].

In this study, HPLC-ESI-MS and HPLC methods were established to explore the differences in the main chemical components and content of Mori Cortex with(mulberry root bark) and without(Mori Cortex) the phellem layer from both qualitative and quantitative aspects. The HPLC-ESI-MS method was used for quality analysis in positive and negative ion modes, and 33 compounds were identified in mulberry root bark, 22 compounds in Mori Cortex, and 26 compounds in phellem layer; mulberry root bark and Mori Cortex shared 22 components, and mulberry root bark has 11 unique compounds; Mori Cortex and its phellem layer shared 15 components, while Mori Cortex has 7 unique compounds. HPLC method was used to simultaneously determine 7 major constituents, including mulberroside A, chlorogenic acid, dihydromorin, oxyresveratrol, moracin O, kuwanon G, and kuwanon H, and the developed method showed good linearity(r>0.998 9) within the concentration range and the recoveries varied from 99.88% to 103.0%, and the RSD was 1.7%-2.9%. The HPLC results showed that the contents of the 7 compounds have great differences in 13 batches samples, compared with mulberry root bark, the contents of mulberroside A, chlorogenic acid, dihydromorin and moracin O of Mori Cortex were increased, while the contents of oxyresveratrol, kuwanon G and kuwanon H were decreased after peeling process. These results can provide a basis for the rationality and quality control of Mori Cortex required to remove the phellem layer.

Inhibition of biofilm in Bacillus amyloliquefaciens Q-426 by diketopiperazines.

Biofilm formation can make significant effects on bacteria habits and biological functions. In this study, diketopiperazines (DKPs) produced by strain of Bacillus amyloliquefaciens Q-426 was found to inhibit biofilm formed in the gas-liquid interface. Four kinds of DKPs were extracted from B. amyloliquefaciens Q-426, and we found that 0.04 mg ml(-1) DKPs could obviously inhibit the biofilm formation of the strain. DKPs produced by B. amyloliquefaciens Q-426 made a reduction on extracellular polymeric substance (EPS) components, polysaccharides, proteins, DNAs, etc. Real-time PCR was performed to determine that whether DKPs could make an obvious effect on the expression level for genes related to biofilm formation in the strain. The relative expression level of genes tasA, epsH, epsG and remB which related to proteins, extracellular matrix, and polysaccharides, were downregulated with 0.04 mg ml(-1) DKPs, while the expression level of nuclease gene nuc was significantly upregulated. The quantitative results of the mRNA expression level for these genes concerted with the quantitative results on EPS levels. All of the experimental results ultimately indicated that DKPs could inhibit the biofilm formation of the strain B. amyloliquefaciens Q-426.

Intensive chemotherapy with dual induction and ALL-like consolidation for childhood acute myeloid leukemia: a respective report from multiple centers in China.

Background: Pediatric acute myeloid leukemia (AML) has poor prognosis and high rate of relapse and mortality, and exploration of new treatment options is still critically needed. Objectives: To summarize the outcome of our new treatment strategies for pediatric AML, which is characterized by dual induction and acute lymphoblastic leukemia (ALL) elements consolidation. Design: Retrospective, single-arm study. Methods: From July 2012 to December 2019, an intensive chemotherapy protocol was used for newly diagnosed children with AML, which contains dual induction, three courses of consolidations based on high-dose cytarabine, and two courses of consolidations composed of high-dose methotrexate, vincristine, asparaginase, and mercaptopurine (ALL-like elements). Blasts were monitored by bone marrow smears at intervals, and two lumbar punctures were performed during chemotherapy. We retrospectively analyzed the efficacy and safety of this study. The last follow-up was on 26 May 2023. Results: A total of 70 pediatric AMLs were included. The median age at diagnosis was 6.7 (0.5-16.0) years. The median initial WBC count was 23.74 × 109/L, 11 of whom ⩾100 × 109/L. After dual induction, there were 62 cases of complete remission (CR), 5 cases of partial remission, and 3 cases of nonremission. The CR rate was 88.57%. The median follow-up time was 5.8 (0.2-9.4) years, the 5-year overall survival was 78.2% ± 5%, the event-free survival (EFS) was 71.2% ± 5.6%, and the cumulative recurrence rate was 27.75%. The 5-year EFS of patients with initial WBC < 100 × 109/L (n = 59) and ⩾100 × 109/L (n = 11) were 76.4% ± 5.7% and 45.5% ± 15% (p = 0.013), respectively. A total of 650 hospital infections occurred. The main causes of infection were respiratory tract infection (26.92%), septicemia (18.46%), stomatitis (11.85%), and skin and soft-tissue infection (10.46%). Conclusion: This intensive treatment protocol with dual induction and ALL-like elements is effective and safe for childhood AML. Initial WBC ⩾ 100 × 109/L was the only independent risk factor in this cohort. Trial registration: It is a retrospective study, and no registration on ClinicalTrials.gov.

One-step detection of Bean pod mottle virus in soybean seeds by the reverse-transcription loop-mediated isothermal amplification.

BACKGROUND: Bean pod mottle virus (BPMV) is a wide-spread and destructive virus that causes huge economic losses in many countries every year. A sensitive, reliable and specific method for rapid surveillance is urgently needed to prevent further spread of BPMV. METHODS: A degenerate reverse-transcription loop-mediated isothermal amplification (RT-LAMP) primer set was designed on the conserved region of BPMV CP gene. The reaction conditions of RT-LAMP were optimized and the feasibility, specificity and sensitivity of this method to detect BPMV were evaluated using the crude RNA rapidly extracted from soybean seeds. RESULTS: The optimized RT-LAMP parameters including 6 mM MgCl2, 0.8 M betaine and temperature at 62.5-65°C could successfully amplify the ladder-like bands from BPMV infected soybean seeds. The amplification was very specific to BPMV that no cross-reaction was observed with other soybean viruses. Inclusion of a fluorescent dye makes it easily be detected in-tube by naked eye. The sensitivity of RT-LAMP assay is higher than the conventional RT-PCR under the conditions tested, and the conventional RT-PCR couldn't be used for detection of BPMV using crude RNA extract from soybean seeds. CONCLUSION: A highly efficient and practical method was developed for the detection of BPMV in soybean seeds by the combination of rapid RNA extraction and RT-LAMP. This RT-LAMP method has great potential for rapid BPMV surveillance and will assist in preventing further spread of this devastating virus.

Hymerhabdrin A, a novel diterpenoid with antifouling activity from the intertidal sponge Hymerhabdia sp.

Hymerhabdrin A (1), a diterpenoid possessing a novel 6/6/5 fused-ring skeleton, together with four known sterols were isolated from an intertidal marine sponge Hymerhabdia sp. Their structures were elucidated by extensive spectroscopic methods, and the relative and absolute configurations of 1 were determined by NOESY analysis and electronic circular dichrosim calculations, respectively. Hymerhabdrin A (1) exhibited significant antifouling activity against Balanus amphitrite larval with LC50 (lethal concentration 50) value of 3.6 µg ml-1.

Chemical constituents and their bioactivities from the fruits of Vitex negundo var. cannabifolia.

Phytochemical investigation of the fruits of Vitex negundo var. cannabifolia led to the isolation of 22 compounds (1-22). Their structures were elucidated mainly by spectroscopic analysis and comparison with the literature data. Among them, compounds 1 and 2 were two new artificial lignans. Primary bioassay showed that the polymethoxyflavones 9-12 displayed moderate-to-weak cytotoxicity against human HepG2 and rat C6 cell lines, while the triterpenoids 13-17 exhibited significant brine shrimp lethality with LC50values of 7.5-29.4 µM.

Flavonoids from the halophyte Apocynum venetum and their antifouling activities against marine biofilm-derived bacteria.

Eleven flavonoids were isolated from the leaves of the halophyte Apocynum venetum. Among them, the isolation of plumbocatechin A (1), 8-O-methylretusin (2) and kaempferol 3-O-(6″-O-acetyl)-ß-D-galactopyranoside (7) was reported for the first time from this plant. Their structures were identified by using spectral methods, including 2D NMR experiments, and confirmed by comparing with the literature data. In addition, the antifouling activities of these compounds against the marine fouling bacteria, Bacillus thuringiensis, Pseudoalteromonas elyakovii and Pseudomonas aeruginosa, have been evaluated in this article.