L-tryptophan anaerobic fermentation for indole acetic acid production: Bacterial enrichment and effects of zero valent iron.

Indole acetic acid (IAA) as a plant hormone, was one of the valuable products of anaerobic fermentation. However, the enriching method remained unknown. Moreover, whether zero valent iron (ZVI) could enhance IAA production was unexplored. In this work, IAA producing bacteria Klebsiella (63 %) was enriched successfully. IAA average production rate and concentration were up to 3 mg/L/h and 56 mg/L. With addition of 1 g/L ZVI, IAA average production rate and concentration was increased for 2 and 3 folds. Mechanisms indicated ZVI increased Na+K+-ATP activity and electron transport activity for 2 folds and 1 fold. Moreover, macro transcription determined indole pyruvate pathway activity like primary-amine oxidase, indole pyruvate decarboxylase and aldehyde dehydrogenase were increased for 146 %, 187 %, and 557 %, respectively. Therefore, ZVI was suitable for enhancement IAA production from mixed culture anaerobic fermentation.

Modular Synthesis of Fluoro-Substituted Furan Compounds via Controllable Fluorination of Biomass-Based 5-HMF and Its Derivatives.

5-Hydroxymethylfurfural (5-HMF) is regarded as one of the most promising platform feedstocks for producing valuable chemicals, fuels, and materials. In this study, we present a controllable fluorination technique for biomass-based 5-HMF and its oxygenated derivatives. This technique allows us to synthesize mono-fluoromethyl, difluoromethyl, and acylfluoro-substituted furan compounds by adjusting experimental conditions such as different fluorine sources and mole ratio. To gain a deeper understanding the reactivity order, we conducted intermolecular and intramolecular competition experiments. The results revealed that the hydroxyl group exhibited the highest reactivity, followed by the aldehyde group. This finding provides important theoretical support and opens up the possibility of selective fluorination. The reaction offers several advantages, including mild conditions, no need for inert gas protection, and easy operation. Furthermore, the fluoro-substituted furan compounds can be further transformed for the preparation of drug analogs, offering a new route for the high-value utilization of biomass molecules.

Tunable Synthesis of Monofluoroalkenes and Gem-Difluoroalkenes via Solvent-Controlled Rhodium-Catalyzed Arylation of 1-Bromo-2,2-difluoroethylene.

Divergent synthesis of fluorine-containing scaffolds starting from a suite of raw materials is an intriguing topic. Herein, we report the solvent-controlled rhodium-catalyzed tunable arylation of 1-bromo-2,2-difluoroethylene. The selection of the reaction solvents provides switchable defluorinated or debrominated arylation from readily available feedstock resources (both arylboronic acids/esters and 1-bromo-2,2-difluoroethylene are commercially available). This switch is feasible because of the difference in coordination ability between the solvent (CH2 Cl2 or CH3 CN) and the rhodium center, resulting in different olefin insertion. This protocol allows the convenient synthesis of monofluoroalkenes and gem-difluoroalkenes, both of which are important scaffolds in the fields of medicine and materials. Moreover, this newly developed solvent-regulated reaction system can be applied to the site-selective dechlorinated arylation of trichloroethylene. Overall, this study provides a useful strategy for the divergent synthesis of fluorine-containing scaffolds and provides insight into the importance of solvent selection in catalytic reactions.

Therapeutic effect of demethylated hydroxylated phillygenin derivative on Helicobacter pylori infection.

Modifying and transforming natural antibacterial products is a novel idea for developing new efficacious compounds. Phillygenin has an inhibitory effect on H. pylori. The aim of the present study was to prepare a phillygenin derivative (PHI-Der) through demethylation and hydroxylation. The minimum inhibitory concentration of 18 strains of H. pylori from different sources was 8-32 µg/mL in vitro, and the activity increased 2-8 times than that of phillygenin. PHI-Der could significantly inhibit the colonization of H. pylori in vivo, reduce the inflammatory response, and promote the repair of inflammatory damage. Further, we used SwissTargetPrediction to predict that its main targets are ALOX5, MCL1, and SLC6A4, and find that it can inhibit bacterial biofilm formation and reduce bacterial infection of cells. It can enhance the intracellular oxidative capacity of H. pylori to inhibit H. pylori growth. Further, it could prevent the oxidation of H. pylori-infected cells and reduce the inflammatory response, which plays a role in protection. In conclusion, compared to phillygenin, PHI-Der had better antibacterial activity and was more effective in treating H. pylori infection. It has characteristics of high safety, specificity, resistance to drug resistance and better antibacterial activity than phillygenin, it's a good antioxidant for host cells.

[Clinical Analysis of Elderly Patients with AML/High-Risk MDS].

OBJECTIVE: To analyze the clinical features of acute myeloid leukemia (AML)/high-risk myelodysplastic syndrome (MDS) patients aged over 60 years old. METHODS: The clinical data of 61 elderly newly diagnosed patients with AML and high-risk MDS who submitted to the Department of Hematology/Oncology of the First Affiliated Hospital of Tsinghua University from January 2009 to April 16, 2021 were retrospectively analyzed. These patients were divided into chemotherapy group (45 cases) and supportive treatment group (16 cases). The overall survival (OS) was analyzed by Kaplan-Meier method, and the prognostic factors of survival were analyzed by multivariate Cox regression. RESULTS: After 2 cycles of induction chemotherapy, the complete remission (CR) rate was 37.8% (17/45), and overall response rate was 62.2% (28/45) in the chemotherapy group. The median OS in the chemotherapy group and supportive treatment group was 11.3 (0.07-43) and 1.6 (0.33-7.72) months, respectively (P<0.001). The median OS in patients who reached CR or did not reach after 1 cycle of induction chemotherapy was 19.8 (10-30.63) and 8.17 (0.07-43) months, respectively (P<0.05), while after 2 cycles was 22.7 (4.2-43) and 7.26 (0.07-26) months, respectively (P<0.001). Univariate analysis showed that age > 80 years old, CCI score > 2, PS score > 2 and supportive treatment were the adverse prognostic factors for OS. Further multivariate analysis suggested that chemotherapy was the only independent prognostic factor for OS (HR=0.140, 95%CI: 0.048-0.409, P<0.001). In the chemotherapy group, univariate analysis showed that CCI score > 2 and failure to reach CR after induction chemotherapy were poor prognostic factors. Multivariate analysis showed that CCI score > 2 (HR=0.139, 95%CI: 0.050-0.384, P<0.001) and failure to achieve CR after induction chemotherapy (HR=0.103, 95%CI: 0.041-0.259, P<0.001) were the adverse prognostic factors for OS. The patients were tolerant to side-effect of chemotherapy. CONCLUSION: Appropriate chemotherapy can prolong the survival of elderly patients with AML and high-risk MDS.

Synthesis of gem-Difluorinated 1,3-Dienes via Synergistic Cu/Pd-Catalyzed Borodifluorovinylation of Alkynes.

gem-Difluoroalkenes (=CF2), which normally act as metabolically stable bioisosteres for carbonyl groups (C═O), are widely applied in agrochemicals and pharmaceuticals and are also used as building blocks in organic synthesis. Herein, an example of Cu/Pd-catalyzed borodifluorovinylation was achieved using alkynes, difluoroethylene bromide, and B2pin2 as chemical feedstocks, providing the corresponding conjugated gem-difluoroalkene scaffold with good functional group compatibility. Moreover, an array of fluorinated synthons can be obtained through further transformations.

Promoter methylation-regulated miR-148a-3p inhibits lung adenocarcinoma (LUAD) progression by targeting MAP3K9.

Lung adenocarcinoma (LUAD) characterized by high metastasis and mortality is the leading subtype of non-small cell lung cancer. Evidence shows that some microRNAs (miRNAs) may act as oncogenes or tumor suppressor genes, leading to malignant tumor occurrence and progression. To better understand the molecular mechanism associated with miRNA methylation in LUAD progression and clinical outcomes, we investigated the correlation between miR-148a-3p methylation and the clinical features of LUAD. In the LUAD cell lines and tumor tissues from patients, miR-148a-3p was found to be significantly downregulated, while the methylation of miR-148a-3p promoter was notably increased. Importantly, miR-148a-3p hypermethylation was closely associated with lymph node metastasis. We demonstrated that mitogen-activated protein (MAP) kinase kinase kinase 9 (MAP3K9) was the target of miR-148a-3p and that MAP3K9 levels were significantly increased in both LUAD cell lines and clinical tumor tissues. In A549 and NCI-H1299 cells, overexpression of miR-148a-3p or silencing MAP3K9 significantly inhibited cell growth, migration, invasion and cytoskeleton reorganization accompanied by suppressing the epithelial-mesenchymal transition. In a nude mouse xenograft assay we found that tumor growth was effectively inhibited by miR-148a-3p overexpression. Taken together, the promoter methylation-associated decrease in miR-148a-3p could lead to lung cancer metastasis by targeting MAP3K9. This study suggests that miR-148a-3p and MAP3K9 may act as novel therapeutic targets for the treatment of LUAD and have potential clinical applications.

[Effects of exogenous methylglyoxal on chesnut seedlings under drought stress]. / å¤–æºç”²åŸºä¹™äºŒé†›å¯¹å¹²æ—±èƒè¿«ä¸‹æ¿æ —å¹¼è‹—çš„å½±å“.

Methylglyoxal (MG) is a novel signaling molecule with multiple functions in plants. To explore the effects of MG on Chinese chestnut (Castanea mollissima) under drought stress, two-year-old 'Huangpeng' chestnut seedlings were treated with 15% polyethylene glycol (PEG) coupled with MG or its scavenger N-acetyl-L-cys-teine (NAC). We measured the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), and glyoxalase enzymes, including glyoxalase Ⅰ (GlyⅠ) and glyoxalase Ⅱ(GlyⅡ). Contents of antioxidants such as endogenous MG, malondialdehyde (MDA), H2O2, and O2-· as well as the osmotic adjustment substances including proline (Pro), soluble sugar (SS), glycine betaine (GB) were also detected. The results showed that 0.5 mmol·L-1 MG significantly increased the activities of antioxidant enzymes (SOD, POD, CAT, APX, GR) and glyoxalase enzymes (GlyⅠ, GlyⅡ) in leaves of chestnut seedlings under drought stress, elevated the contents of osmotic adjustment substances (Pro, SS, GB) and antioxidant substances (ASA, GSH), and reduced the contents of MG, MDA, H2O2, O2-· and dehydroascorbate (DHA). Drought stress induced damages such as membrane lipid peroxidation and osmotic stress was alleviated by MG, leading to an overall improved adaptability of chestnut to drought stress. Moreover, the addition of MG scavenger NAC could reverse the effects induced by MG, indicating that MG had positive impacts on drought resistance of chestnut plants. Our study provided a theoretical basis for further exploring the mechanism of MG in alleviating drought stress induced symptoms in chestnut.

Polymerase chain reaction-based assays facilitate the breeding and study of mouse models of Klinefelter syndrome.

Klinefelter syndrome (KS) is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia. The breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological mechanism. Karyotyping and fluorescence in situ hybridization are reliable methods for identifying chromosomal contents. However, technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target mice. To overcome these limitations, we developed three polymerase chain reaction-based assays to measure specific genetic information, including presence or absence of the sex determining region of chromosome Y (Sry), copy number of amelogenin, X-linked (Amelx), and inactive X specific transcripts (Xist) levels. Through a combined analysis of the assay results, we can infer the karyotype of target mice. We confirmed the utility of our assays with the successful generation of KS mouse models. Our assays are rapid, inexpensive, high capacity, easy to perform, and only require small sample amounts. Therefore, they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.

Transition-Metal-Free Valorization of Biomass-derived Levulinic Acid Derivatives: Synthesis of Curcumene and Xanthorrhizol.

Levulinic acid (LA) is acknowledged one of the most promising biomass-derived platform molecules and can be transformed into various value-added chemicals. Here, we report a new reaction process for the valorization of LA derivatives under transition-metal-free condition. The protocol combined with the conversion of the levulinate to tosylhydrazone and base promoted arylation, acylation, and etherification cross-coupling. Moreover, our method was applied to synthesize three biologically active molecules, rac-curcumene, rac-xanthorrhizol and rac-4,7-dimethyl-l-tetralone. This reaction discloses a new avenue for the high-value utilization of platform molecules.

Effects of artificial light at night on foraging behavior and vigilance in a nocturnal rodent.

Artificial light at night has greatly changed the physical environment for many organisms on a global scale. As an energy efficient light resource, light emitting diodes (LEDs) have been widely used in recent years. As LEDs often have a broad spectrum, many biological processes may be potentially affected. In this study, we conducted manipulated experiments in rat-proof enclosures to explore the effects of LED night lighting on behavior of a nocturnal rodent, the Mongolian five-toed jerboa (Allactaga sibirica). We adopted the giving-up density (GUD) method and camera video trapping to study behavioral responses in terms of patch use, searching efficiency and vigilance. With the presence of white LED lighting, jerboas spent less time in patches, foraged less intensively (with higher GUDs) and became vigilant more frequently, while their searching efficiency was higher than under dark treatment. Although both positive and negative effects of LEDs on foraging were detected, the net effect of LEDs on jerboas is negative, which may further translate into changes in population dynamics, inter-specific interaction and community structure. To our knowledge, this is the first field study to explore how LED lighting affect foraging behavior and searching efficiency in rodents. Our results may have potential implications for practices such as pest control.

The dual-catalyzed boryldifluoroallylation of alkynes: an efficient method for the synthesis of skipped gem-difluorodienes.

The Cu/Pd-catalyzed boryldifluoroallylation of alkynes was achieved, providing the corresponding skipped gem-difluorodiene scaffolds with high regio- and stereoselectivity in moderate to excellent yields. This new approach has good functional group compatibility for both alkynes and 3,3-difluoro-substituted allylic esters. Moreover, an array of synthetic building blocks, skipped dienes, trienes, and drug mimics can be obtained via further transformations.

Arabidopsis mtHSC70-1 plays important roles in the establishment of COX-dependent respiration and redox homeostasis.

The 70 kDa heat shock proteins function as molecular chaperones and are involved in diverse cellular processes. However, the functions of the plant mitochondrial HSP70s (mtHSC70s) remain unclear. Severe growth defects were observed in the Arabidopsis thaliana mtHSC70-1 knockout lines, mthsc70-1a and mthsc70-1b. Conversely, the introduction of the mtHSC70-1 gene into the mthsc70-1a background fully reversed the phenotypes, indicating that mtHSC70-1 is essential for plant growth. The loss of mtHSC70-1 functions resulted in abnormal mitochondria and alterations to respiration because of an inhibition of the cytochrome c oxidase (COX) pathway and the activation of the alternative respiratory pathway. Defects in COX assembly were observed in the mtHSC70-1 knockout lines, leading to decreased COX activity. The mtHSC70-1 knockout plants have increased levels of reactive oxygen species (ROS). The introduction of the Mn-superoxide dismutase 1 (MSD1) or the catalase 1 (CAT1) gene into the mthsc70-1a plants decreased ROS levels, reduced the expression of alternative oxidase, and partially rescued growth. Taken together, our data suggest that mtHSC70-1 plays important roles in the establishment of COX-dependent respiration.

Zinc finger E-box-binding homeobox 1 mediates aerobic glycolysis via suppression of sirtuin 3 in pancreatic cancer.

AIM: To uncover the roles of tumor-promoting gene ZEB1 in aerobic glycolysis regulation and shed light on the underlying molecular mechanism. METHODS: Endogenous zinc finger E-box binding homeobox-1 (ZEB1) was silenced using a lentivirus-mediated method, and the impact of ZEB1 and methyl-CpG binding domain protein 1 (MBD1) on aerobic glycolysis was measured using seahorse cellular flux analyzers, reactive oxygen species quantification, and mitochondrial membrane potential measurement. The interaction between ZEB1 and MBD1 was assessed by co-immunoprecipitation and immunofluorescence assays. The impact of ZEB1 and MBD1 interaction on sirtuin 3 (SIRT3) expression was confirmed by quantitative polymerase chain reaction, western blotting, and dual-luciferase and chromatin-immunoprecipitation assays. RESULTS: ZEB1 was a positive regulator of aerobic glycolysis in pancreatic cancer. ZEB1 transcriptionally silenced expression of SIRT3, a mitochondrial-localized tumor suppressor, through interaction with MBD1. CONCLUSION: ZEB1 silenced SIRT3 expression via interaction with MBD1 to promote aerobic glycolysis in pancreatic cancer.

Determination of sitafloxacin in human plasma by liquid chromatography-tandem mass spectrometry method: application to a pharmacokinetic study.

A high-performance liquid chromatographic-tandem mass spectrometric (HPLC-MS/MS) method was developed and validated to determine sitafloxacin in human plasma with dextrorphan as internal standard. Chromatographic separation was performed on a ZORBAX SB-C18 column (3.5µm, 2.1mm×100mm) with the mobile phase of methanol/water (containing 0.1% formic acid) (46:54, v/v) at a flow rate of 0.2mL/min. Quantification was performed using multiple-reaction monitoring of the transitions at m/z 410.2 → 392.2 for sitafloxacin and m/z 258.1 → 157.1 for dextrorphan, respectively. The calibration curve was linear over the range of 5-2500ng/mL with the lower limit of quantification of 5ng/mL for sitafloxacin. The intra- and inter-day precisions were less than 8.3% and the deviations of assay accuracies were within ±4.1%. Sitafloxacin was sufficiently stable under all relevant analytical conditions. This method was successfully applied to the pharmacokinetic study of sitafloxacin in healthy Chinese volunteers.

Simultaneous quantitative analysis of dextromethorphan, dextrorphan and chlorphenamine in human plasma by liquid chromatography-electrospray tandem mass spectrometry.

A sensitive and accurate HPLC-MS/MS method was developed for the simultaneous determination of dextromethorphan, dextrorphan and chlorphenamine in human plasma. Three analytes were extracted from plasma by liquid-liquid extraction using ethyl acetate and separated on a Kromasil 60-5CN column (3 µm, 2.1 × 150 mm) with mobile phase of acetonitrile-water (containing 0.1% formic acid; 50:50, v/v) at a flow rate of 0.2 mL/min. Quantification was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode using positive electrospray ionization. The calibration curve was linear over the range of 0.01-5 ng/mL for dextromethorphan, 0.02-5 ng/mL for dextrorphan and 0.025-20 ng/mL for chlorphenamine. The lower limits of quantification for dextromethorphan, dextrorphan and chlorphenamine were 0.01, 0.02 and 0.025 ng/mL, respectively. The intra- and inter-day precisions were within 11% and accuracies were in the range of 92.9-102.5%. All analytes were proved to be stable during sample storage, preparation and analytic procedures. This method was first applied to the pharmacokinetic study in healthy Chinese volunteers after a single oral dose of the formulation containing dextromethorphan hydrobromide (18 mg) and chlorpheniramine malaeate (8 mg).

Ligamentum teres hepatis patch enhances the healing of pancreatic fistula after distal pancreatectomy.

Pancreatic fistula is one of the most common complications after the distal pancreatectomy. Many methods have been tried to solve the problem, but no one is optimal, especially for the soft pancreatic stump cases. This study used ligamentum teres hepatis as a patch to cover the pancreatic stump. Between October 2010 and December 2012, seventy-seven patients who had undergone distal pancreatectomy with a soft pancreatic stump were divided into two groups: group A (n=39, patients received conventional ligated main pancreatic duct method) and group B (n=38, patients underwent a coverage procedure). Patients in group A had a longer recovery from postoperative pancreatic fistula than those in group B (16.4+/-3.5 vs 10.8+/-1.6 days, P<0.05). The coverage procedure with ligamentum teres hepatis is a safe, effective and convenient method for patients with a soft pancreas remnant during distal pancreatectomy.

[Progress in the study of some important natural bioactive cyclopeptides].

Natural cyclopeptides are hot spots in chemical and pharmaceutical fields because of the wide spreading bio-resources, complex molecular structures and various bioactivities. Bio-producers of cyclopeptides distribute over almost every kingdom from bacteria to plants and animals. Many cyclopeptides contain non-coded amino acids and non-pepditic bonds. Most exciting characteristic of cyclopeptides is a range of interesting bioactivities such as antibiotics gramicidin-S (2), vancomycin (3) and daptomycin (4), immunosuppressive cyclosporin-A (1) and astin-C (8), and anti-tumor aplidine (5), RA-V (6) and RA-VII (7). Compounds 1-4 are being used in clinics; compounds 5-8 are in the stages of clinical trial or as a candidate for drug research. In this review, the progress in chemical and bioactive studies on these important natural bioactive cyclopeptides 1-8 are introduced, mainly including discovery, bioactivity, mechanism, QSAR and synthesis.

Cyclopeptide Alkaloids from Ziziphus apetala.

Six novel Ia3-type cyclopeptide alkaloids (1-6) were isolated from stems of Ziziphus apetala. Compound 5 and the known compounds mauritine A (7) and mauritine F (8) were isolated from the roots. Their structures were determined by spectroscopic analyses and chemical methods. The total alkaloids from the roots and the isolated cyclopeptide alkaloids were tested for antidepressant behavior on mice, cytotoxicity, and 11ß-hydroxysteroid dehydrogenase (11ß-HSD) inhibition in vitro. Only mauritine A (7) showed inhibitory activity on 11ß-HSD1, with IC50 values of 52.0 (human) and 31.2 µg/mL (mouse).

Effects of social exclusion on depressive symptoms: elderly Chinese living alone in Shanghai, China.

Research has identified social exclusion as one of the social determinants of health. There are risks of social exclusion in later life in recent years. However, despite the fact that China has the largest aging population in the world and reports a rapid growth in the proportion of older people living alone, research on the role of social exclusion on depression is limited. This study examined the effects of social exclusion on depressive symptoms in older Chinese who are living alone in China, based on the data from one Shanghai neighbourhood. The data used were obtained between August and October 2008 through face-to-face interviews, using a structured survey questionnaire, from a simple random sample of 228 Chinese 60 and older living alone in a Shanghai community. Depressive symptoms were measured by a 15-item Chinese version Geriatric Depression Scale. Social exclusion was represented by income adequacy, social relations, civic participation, and housing condition. Over 30% of participants reported symptoms of a mild or above mild level of depression. When controlled for the demographics and health variables in hierarchical multiple regression, social exclusion variables, represented by a lower level income adequacy, a less favourable housing condition, and feeling more lonely correlated significantly with more depressive symptoms. Contrary to previous studies on depression in the older adults in China, this study has obtained findings indicating that social exclusion variables are more important than other socio-demographic factors in the context of contemporary China. While two significant social exclusion variables (i.e. income and housing) are related to structural changes in the economic context in China, the intra-personal role of feeling lonely that ties strongly living alone and role of older adults in an increasingly competitive market economy should not be underestimated. To address depression and mental health of older Chinese who live alone, social policies and programs to reduce various forms of social exclusion should be developed. In additional to providing assistance in financial support and housing improvement, services to strengthen the social networks and social relations of these older people are essential.