[Analysis of saliva and intestinal microbial community in children with severe caries based on 16S rDNA high-throughput sequencing technology].

PURPOSE: The characteristics of saliva and intestinal microbial community in children with high caries and no caries were analyzed by 16S rDNA high-throughput sequencing. METHODS: Among 431 children aged 3-5 years old in Zunyi City who were investigated previously by our team, 25 children in the high caries group and the same in the caries-free group were selected for fecal and saliva samples. 16S rDNA high-throughput sequencing was used to analyze the bacterial flora structure of the samples and identify the species with different relative abundance at the species level. SPSS 18.0 software package was used for data analysis. RESULTS: The diversity of intestinal flora in the high caries group was higher than that in the caries-free group, and the difference was statistically significant(P＜0.05). The diversity of salivary flora in the high caries group was more than that in the caries-free group, with no significant difference(P＞0.05). At phylum level,there was no significant difference in intestinal and salivary flora between children with high caries and children without caries. At gene level, Blautia, [Eubacterium] hallii group and [Eubacterium] eligens group in the intestine of caries-free group were significantly higher than those of high caries group(P＜0.05), while Parasutterella and Christensenellaceae R-7 group were significantly lower than those of high caries group(P＜0.05). At gene level, Peptostreptococcus in saliva of caries-free group was significantly higher than that in high caries group(P＜0.05). Dialister, Kingella, Escherichia-Shigella and Treponema in saliva of caries-free group were significantly lower than those in high caries group(P＜0.05). CONCLUSIONS: There are significant differences in species composition of intestinal flora but no in salivary flora between children with high caries and children without caries.

Development and validation of a random survival forest model for predicting long-term survival of early-stage young breast cancer patients based on the SEER database and an external validation cohort.

Young breast cancer (YBC) patients often face a poor prognosis, hence it's necessary to construct a model that can accurately predict their long-term survival in early stage. To realize this goal, we utilized data from the Surveillance, Epidemiology, and End Results (SEER) databases between January 2010 and December 2020, and meanwhile, enrolled an independent external cohort from Tianjin Medical University Cancer Institute and Hospital. The study aimed to develop and validate a prediction model constructed using the Random Survival Forest (RSF) machine learning algorithm. By applying the Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis, we pinpointed key prognostic factors for YBC patients, which were used to create a prediction model capable of forecasting the 3-year, 5-year, 7-year, and 10-year survival rates of YBC patients. The RSF model constructed in the study demonstrated exceptional performance, achieving C-index values of 0.920 in the training set, 0.789 in the internal validation set, and 0.701 in the external validation set, outperforming the Cox regression model. The model's calibration was confirmed by Brier scores at various time points, showcasing its excellent accuracy in prediction. Decision curve analysis (DCA) underscored the model's importance in clinical application, and the Shapley Additive Explanations (SHAP) plots highlighted the importance of key variables. The RSF model also proved valuable in risk stratification, which has effectively categorized patients based on their survival risks. In summary, this study has constructed a well-performed prediction model for the evaluation of prognostic factors influencing the long-term survival of early-stage YBC patients, which is significant in risk stratification when physicians handle YBC patients in clinical settings.

The complete mitochondrial genome of the freshwater crab Tenuilapotamon latilum kaiyangense Dai et Li,1985 (Decapoda: Brachyura: Potamoidea).

We first reported the complete mitochondrial genome of Tenuilapotamon latilum kaiyangense (Decapoda: Brachyura: Potamoidea). The genome is 19,294 bp in length, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region. The whole mitochondrial genome is characterized by the apparent AT bias (74.19%). This research provides DNA data for further researches on population genetics and phylogenetics.

The complete mitochondrial genome of the freshwater crab Bottapotamon lingchuanense Türkay and Dai 1997 (Decapoda: Brachyura: Potamoidea).

We report the complete mitochondrial genome of Bottapotamon lingchuanense for the first time, which is found to be 17,612 base pairs in length, and contains 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA), and 1 non-coding AT-rich region known as the D-loop. In addition, the mitogenome has 17 intergenic regions ranging from 1 to 1512 bp in length. The mitochondrial genome of B. lingchuanense is the first mitochondrial genome under the genus Bottapotamon, providing DNA data for species identification, enriching the species diversity of Brachyura. The maximum-likelihood (ML) tree and Bayesian inference (BI) tree based on the 13 PCGs of mitochondrial genome of Brachyura species showed similar topologies with high confidence, and the analysis results were consistent with the current mainstream classification system. The results indicating that B. lingchuanense is closely related to Neilupotamon sinense, Sinopotamon, and Tenuilapotamon, and it is likely to be derived from them.

Systematic Review and Pharmacological Considerations for Chloroquine and Its Analogs in the Treatment for COVID-19.

COVID-19 has been announced pandemic by WHO and over 17,000,000 people infected (Till April 21st 2020). The disease is currently under control in China, with a curative rate of 86.8%. Chloroquine (CQ) is an old anti-malarial drug with good tolerability, which had proved to be effective in previous SARS-coronavirus, which spread and disappeared between 2002-2003. In vitro studies demonstrated the efficacy of CQ in curing COVID-19. Consequently, via analytical PBPK modeling, a further preliminary clinical trial has proved the efficacy and safety of CQ in China., and multiple clinical trials were registered and approved to investigate the activity of other analogs of CQ against COVID-19. We have listed all the clinical trials and made a meta-analysis of published data of hydroxychloroquine (HCQ). HCQ could increase the CT improvement and adverse reactions (ADRs) significantly though there was considerable heterogeneity among current researches. Actually, CQ and its analogs have unique pharmacokinetic characteristics, which would induce severe side effects in some circumstances. We have then summarized pharmacological considerations for these drugs so as to provide to the busy clinicians to avoid potential side effects when administered CQ or its analogs to COVID-19 patients, especially in the elderly, pediatrics, and pregnancies.

Peripheral and cerebral abnormalities of the tryptophan metabolism in the depression-like rats induced by chronic unpredicted mild stress.

Tryptophan (TRP) metabolism could occur both peripherally and centrally, which plays an essential role in brain and gastrointestinal disorders. The participation of TRP metabolism in the bidirectional brain-gut interactions is of value to better understand the mechanism of the pathophysiology of depression. To compare the difference between peripheral and cerebral TRP metabolism in depression, the chronic unpredicted mild stress (CUMS) was used to induce depressive-like syndrome in rats. After the rats were subjected to CUMS for five weeks, TRP and its metabolites were determined by prominence ultrafast liquid chromatography (UFLC) coupled with a QTRAP 5500 mass spectrometer (UFLC-QTRAP-5500/MS), and the expression of TRP metabolic enzymes were examined by Real-time quantitative PCR (qRT-PCR). CUMS induced TRP metabolism abnormalities in the colon, cortex and hippocampus of rats. There were regional metabolism differences, but the common points were the upregulation of indoleamine-2,3-dioxygenase 1 (IDO1) and the increased contents of Kynurenine (KYN), which suggested that KYN pathway (KP) was more favored than the serotonin (5-HT) pathway in the TRP metabolism under CUMS in the three regions studied. More importantly, KYN was preferentially metabolized into neurotoxic 3-hydroxycaninuric acid (3-HK) branch in the cortex and hippocampus while Kynurenic acid (KA) branch in the colon under CUMS. Interestingly, according to the Pearson's correlation coefficients, there may be correlations between the colonic KYN and cerebral 3-HK and KA. It advances our understanding of the role of TRP metabolism in gut-brain communication and provides new research ideas and methods for depression.

Study on the Material Basis of Neuroprotection of Myrica rubra Bark.

Background: Increasing attention has been given to the search for neuroprotective ingredients from natural plants. Myrica rubra bark (MRB) has been used in traditional oriental medicine for over thousand years and has potential neuroprotection. Methods and Results: Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was used to identify the compounds in MRB extract, and the MTT assay was performed to evaluate the neuroprotection of six major compounds from MRB against glutamate-induced damage in PC12 cells. The result displayed nineteen compounds were identified, and myricitrin and myricanol 11-sulfate were shown to have neuroprotection, which prevented cell apoptosis through alleviating oxidative stress by reducing the levels of reactive oxygen species and methane dicarboxylic aldehyde, as well as by enhancing the activities of superoxide dismutase. Conclusions: Several active compounds from MRB may offer neuroprotection and have the potential for the development of new drugs against central nervous system diseases.

Colonization on Cucumber Root and Enhancement of Chlorimuron-ethyl Degradation in the Rhizosphere by Hansschlegelia zhihuaiae S113 and Root Exudates.

The colonization of Hansschlegelia zhihuaiae S113 and its degradation of the herbicide chlorimuron-ethyl in the cucumber rhizosphere was investigated. The results reveal that S113 colonized the cucumber roots (2.14 × 105cells per gram of roots) and were able to survive in the rhizosphere (maintained for 20 d). The root exudates promoted colonization on roots and increased the degradation of chlorimuron-ethyl by S113. Five organic acids in cucumber-root exudates were detected and identified by HPLC. Citric acid and fumaric acid significantly stimulated S113 colonization on cucumber roots, with 18.4 and 15.5% increases, respectively, compared with the control. After irrigation with an S113 solution for 10 days, chlorimuron-ethyl could not be detected in the roots, seedlings, or rhizosphere soil, which allowed for improved cucumber growth. Therefore, the degradation mechanism of chlorimuron-ethyl residues by S113 in the rhizosphere could be applied in situ for the bioremediation of chlorimuron-ethyl contaminated soil to ensure crop safety.

Biochemical characterization of an enantioselective esterase from Brevundimonas sp. LY-2.

BACKGROUND: Lactofen, a member of the diphenylether herbicides, has high activity and is commonly used to control broadleaf weeds. As a post-emergent herbicide, it is directly released to the environment, and easily caused the pollution. This herbicide is degraded in soil mainly by microbial activity, but the functional enzyme involved in the biodegradation of lactofen is still not clear now. RESULTS: A novel esterase gene lacH, involved in the degradation of lactofen, was cloned from the strain Brevundimonas sp. LY-2. The gene contained an open reading frame of 921 bp, and a putative signal peptide at the N-terminal was identified with the most likely cleavage site between Ala 28 and Ala 29. The encoded protein, LacH, could catalyze the hydrolysis of lactofen to form acifluorfen. Phylogenetic analysis showed that LacH belong to family V of bacterial lipolytic enzymes. Biochemical characterization analysis showed that LacH was a neutral esterase with an optimal pH of 7.0 and an optimal temperature of 40 °C toward lactofen. Besides, the activity of LacH was strongly inhibited by Hg2+ and Zn2+. LacH preferred short chain p-nitrophenyl esters (C2-C6), exhibited maximum activity toward p-nitrophenyl acetate. Furthermore, the enantioselectivity of LacH during lactofen hydrolysis was also studied, and the results show that R-(-)-lactofen was degraded faster than S-(+)-lactofen, indicating the occurrence of enantioselectivity in the enzymatic reaction. CONCLUSIONS: Our studies characterized a novel esterase involved in the biodegradation of diphenylether herbicide lactofen. The esterase showed enantioselectivity during lactofen degradation, which revealed the occurrence of enzyme-mediated enantioselective degradation of chiral herbicides.

The Effects of Rheum palmatum L. on the Pharmacokinetic of Major Diterpene Alkaloids of Aconitum carmichaelii Debx. in Rats.

BACKGROUND AND OBJECTIVES: Aconitum carmichaelii Debx. (Fuzi) is usually compatible with Rheum palmatum L. (Dahuang) in clinic. The study is conducted to investigate the influence of Dahuang on the pharmacokinetics of Fuzi. METHODS: Twelve rats were randomly divided into two groups. Fuzi group was orally administered a single dose of 38.4 mg/kg total alkaloids from Fuzi, and Fuzi-Dahuang group was given 38.4 mg/kg total alkaloids from Fuzi and 76.8 mg/kg Dahuang anthraquinones at the same time. The plasma concentrations of aconitine (AC), mesaconitine (MC), and hypaconitine (HC), benzoylaconine (BAC), benzoylmesaconine (BMC), benzoylhypaconine (BHC), and aconine (ACN) were determined by ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry method. The pharmacokinetic parameters were calculated including maximum plasma concentration (C max), area under the plasma concentration-time curve in all time-points (AUClast), apparent volume of distribution (V z/F), apparent plasma clearance (CL/F), elimination half-life (T 1/2), and time to achieve maximum concentration (T max). RESULTS: AUClast of diester diterpene alkaloids (DDAs) were 58.20, 169.78, 278.48 ng·h/mL for AC, MC, and HC in Fuzi-Dahuang group which were remarkably lower than that in Fuzi group (71.62, 183.13, 410.59 ng·h/mL for AC, MC, HC). CL/F was significantly increased from 173.88 to 218.85 mL/h for AC, 433.22 to 800.21 mL/h for MC, 1150.61 to 1307.30 mL/h for HC after combination. However, with the significantly increased C max, AUClast of monoester diterpene alkaloids (MDAs) and amine diterpenoid alkaloids (ADAs) were 152.42, 1238.95, 287.96, 123.33 ng·h/mL for BAC, BHC, BMC, ACN in Fuzi-Dahuang group which were remarkably higher than that in Fuzi group (54.47, 1105.48, 200.75, 86.48 ng·h/mL for BAC, BHC, BMC, ACN). At the same time, CL/F was significantly decreased from 1030.15 to 607.09, 3594.06 to 1437.54, 1441.23 to 1310.14, and 391.30 to 239.50 mL/h for each one after combination. CONCLUSIONS: Fuzi diterpene alkaloids pharmacokinetics was greatly influenced by Dahuang which may account for the compatibility mechanism of effect-enhancing and toxicity-reducing.

Cloning, expression and mutation of a triazophos hydrolase gene from Burkholderia sp. SZL-1.

Triazophos is a broad-spectrum and highly effective insecticide, and the residues of triazophos have been frequently detected in the environment. A triazophos-degrading bacterium, Burkholderia sp. SZL-1, was isolated from a long-term triazophos-polluted soil. Strain SZL-1 could hydrolyze triazophos to 1-phenyl-3-hydroxy-1,2,4-triazole, which was further utilized as the carbon sources for growth. The triazophos hydrolase gene trhA, cloned from strain SZL-1, was expressed and homogenously purified using Ni-nitrilotriacetic acid affinity chromatography. TrhA is 55 kDa and displays maximum activity at 25°C, pH 8.0. This enzyme still has nearly 60% activity at the range of 15°C-50°C for 30 min. TrhA was mutated by sequential error prone PCR and screened for improved activity for triazophos degradation. One purified variant protein (Val89-Gly89) named TrhA-M1 showed up to 3-fold improvement in specific activity against triazophos, and the specificity constants of Kcat and Kcat/Km for TrhA-M1 were improved up to 2.3- and 8.28-fold, respectively, compared to the wild-type enzyme. The results in this paper provided potential material for the contaminated soil remediation and hydrolase genetic structure research.