tert-Butyl Nitrite-Induced Radical Nitrile Oxidation Cycloaddition: Synthesis of Isoxazole/Isoxazoline-Fused Benzo 6/7/8-membered Oxacyclic Ketones.

A practical metal-free and additive-free approach for the synthesis of 6/7/8-membered oxacyclic ketone-fused isoxazoles/isoxazolines tetracyclic or tricyclic structures is reported through Csp3-H bond radical nitrile oxidation and the intramolecular cycloaddition of alkenyl/alkynyl-substituted aryl methyl ketones. This convenient approach enables the simultaneous formation of isoxazole/isoxazoline and 6/7/8-membered oxacyclic ketones to form polycyclic architectures by using tert-butyl nitrite (TBN) as a non-metallic radical initiator and N-O fragment donor.

Quaternized chitosan-based organic-inorganic nanohybrid nanoparticles loaded with prothioconazole for efficient management of fungal diseases with minimal environmental impact.

Poor foliar deposition and retention of pesticides results in serious pesticide residues and environmental pollution. Organic-inorganic hybridized nanoparticles (OIHN), combining the advantages of organic and inorganic materials, can be used as carriers to load pesticides for efficient and safe application. Herein, a novel multifunctional OIHN composed of mesoporous silica nanoparticles (MSNs) and cationic chitosan quaternary ammonium salt (HACC) was constructed and used as a delivery system for prothioconazole (PTC). The resultant PTC@MSNs-HACC exhibited a remarkable loading capacity of 39.07 wt% and demonstrated enhanced PTC release (31.47 %) under alkaline conditions. The UV-shielding properties of MSNs efficiently shielded PTC from photodegradation, increasing its photostability by over threefold. The strong positive charge of HACC conferred excellent adhesion of PTC@MSNs-HACC to fungal cell membranes, leading to high deposition on wheat leaves with improved rain-wash resistance (increased by 30 %). Consequently, PTC@MSNs-HACC (EC50: 12.48 mg/L) exhibited superior wheat scab control compared to PTC emulsifiable concentrate (EC50: 28.49 mg/L). Additionally, PTC@MSNs-HACC displayed excellent uptake and transport in plants, ensuring plant safety and reducing toxicity to zebrafish by >1-fold. The potential application of the developed PTC@MSNs-HACC in agricultural production holds significant promise and is anticipated to find widespread use in the future.

Protease inhibitor ASP enhances freezing tolerance by inhibiting protein degradation in kumquat.

Cold acclimation is a complex biological process leading to the development of freezing tolerance in plants. In this study, we demonstrated that cold-induced expression of protease inhibitor FmASP in a Citrus-relative species kumquat [Fortunella margarita (Lour.) Swingle] contributes to its freezing tolerance by minimizing protein degradation. Firstly, we found that only cold-acclimated kumquat plants, despite extensive leaf cellular damage during freezing, were able to resume their normal growth upon stress relief. To dissect the impact of cold acclimation on this anti-freezing performance, we conducted protein abundance assays and quantitative proteomic analysis of kumquat leaves subjected to cold acclimation (4°C), freezing treatment (-10°C) and post-freezing recovery (25°C). FmASP (Against Serine Protease) and several non-specific proteases were identified as differentially expressed proteins induced by cold acclimation and associated with stable protein abundance throughout the course of low-temperature treatment. FmASP was further characterized as a robust inhibitor of multiple proteases. In addition, heterogeneous expression of FmASP in Arabidopsis confirmed its positive role in freezing tolerance. Finally, we proposed a working model of FmASP and illustrated how this extracellular-localized protease inhibitor protects proteins from degradation, thereby maintaining essential cellular function for post-freezing recovery. These findings revealed the important role of protease inhibition in freezing response and provide insights on how this role may help develop new strategies to enhance plant freezing tolerance.

Enhanced control efficacy of spinosad on corn borer using polylactic acid encapsulated mesoporous silica nanoparticles as a smart delivery system.

Asion corn borer (Ostrinia furnacalis (Guenee)) is one of the most important factors affecting the normal growth and yield of corn. However, chemical control methods currently in use cause severe pollution. In the present study, aminated mesoporous silica nanoparticles (MSNs-NH2) and polylactic acid (PLA) were used as the carrier and capping agent respectively to construct an insect gut microenvironment nano-response system that loaded spinosad, a biopesticide used to control O. furnacalis. The resulting spinosad@MSNs-PLA demonstrated high loading capacity (38.6 %) and improved photostability of spinosad. Moreover, this delivery system could intelligently respond to the intestinal microenvironment of the corn borer's gut and achieve the smart release of spinosad. Compared with the conventional pesticide, spinosad@MSNs-PLA exhibited superior efficacy in controlling the O. furnacalis and could uptake and transport in maize plants without adverse effects on their growth. Furthermore, the toxicity of spinosad@MSNs-PLA on zebrafish was reduced by over 50 times. The prepared spinosad@MSNs-PLA has great potential and could be widely applied in agricultural production in the future. This approach could improve the utilization of pesticide and reduce environmental pollution. In addition, MSNs-PLA nano vectors provide new ideas for the control of other borer pests.

Reduced SUMOylation of Nrf2 signaling contributes to its inhibition induced by amyloid-ß.

Oxidative stress induced by amyloid-ß (Aß) has been considered as one of the important mechanisms in the development of Alzheimer disease (AD). The inhibition of endogenous antioxidant Nrf2 signaling in the brain of AD patients aggravates the oxidative damage, however, the causes of Nrf2 signaling inhibition are unclear. It is reported that smallubiquitin-like modification (SUMOylation) is involved in the process of oxidative injury. To investigate whether and how SUMOylation was involved in the inhibition of Nrf2 signaling pathway induced by Aß, Aß intrahippocampal injection rat model and Aß treated SH-SY5Y cell model were used in the current study. Small interfering RNA and lentivirus transfection were used to intervene SUMOylation, and the level of SUMOylation was assessed by immunoprecipitation. The present in vivo and in vitro studies revealed that SUMOylation levels of Nrf2 and MafF, as well as the overall SUMOylation level were reduced under long-term Aß insult. Meanwhile, the binding of Nrf2 to MafF was decreased, accompanied by low interaction with antioxidant response element (ARE) area of gene. Down-regulation of SUMO protein exacerbated the Aß-induced inhibition of Nrf2 signaling pathway, while, enhancement of SUMOylation of Nrf2 and MafF by overexpression of Ubc9 reversed this process. These results imply that reduction in SUMOylation induced by Aß contributed to the inhibition of Nrf2 signaling, and SUMOylation might be a potential therapeutic target of AD.

Comparative Analysis of Acanthopanacis Cortex and Periplocae Cortex Using an Electronic Nose and Gas Chromatography-Mass Spectrometry Coupled with Multivariate Statistical Analysis.

Chinese Herbal Medicines (CHMs) can be identified by experts according to their odors. However, the identification of these medicines is subjective and requires long-term experience. The samples of Acanthopanacis Cortex and Periplocae Cortex used were dried cortexes, which are often confused in the market due to their similar appearance, but their chemical composition and odor are different. The clinical use of the two herbs is different, but the phenomenon of being confused with each other often occurs. Therefore, we used an electronic nose (E-nose) to explore the differences in odor information between the two species for fast and robust discrimination, in order to provide a scientific basis for avoiding confusion and misuse in the process of production, circulation and clinical use. In this study, the odor and volatile components of these two medicinal materials were detected by the E-nose and by gas chromatography-mass spectrometry (GC-MS), respectively. An E-nose combined with pattern analysis methods such as principal component analysis (PCA) and partial least squares (PLS) was used to discriminate the cortex samples. The E-nose was used to determine the odors of the samples and enable rapid differentiation of Acanthopanacis Cortex and Periplocae Cortex. GC-MS was utilized to reveal the differences between the volatile constituents of Acanthopanacis Cortex and Periplocae Cortex. In all, 82 components including 9 co-contained components were extracted by chromatographic peak integration and matching, and 24 constituents could be used as chemical markers to distinguish these two species. The E-nose detection technology is able to discriminate between Acanthopanacis Cortex and Periplocae Cortex, with GC-MS providing support to determine the material basis of the E-nose sensors' response. The proposed method is rapid, simple, eco-friendly and can successfully differentiate these two medicinal materials by their odors. It can be applied to quality control links such as online detection, and also provide reference for the establishment of other rapid detection methods. The further development and utilization of this technology is conducive to the further supervision of the quality of CHMs and the healthy development of the industry.

AMPK induces degradation of the transcriptional repressor PROX1 impairing branched amino acid metabolism and tumourigenesis.

Tumour cell metabolic plasticity is essential for tumour progression and therapeutic responses, yet the underlying mechanisms remain poorly understood. Here, we identify Prospero-related homeobox 1 (PROX1) as a crucial factor for tumour metabolic plasticity. Notably, PROX1 is reduced by glucose starvation or AMP-activated protein kinase (AMPK) activation and is elevated in liver kinase B1 (LKB1)-deficient tumours. Furthermore, the Ser79 phosphorylation of PROX1 by AMPK enhances the recruitment of CUL4-DDB1 ubiquitin ligase to promote PROX1 degradation. Downregulation of PROX1 activates branched-chain amino acids (BCAA) degradation through mediating epigenetic modifications and inhibits mammalian target-of-rapamycin (mTOR) signalling. Importantly, PROX1 deficiency or Ser79 phosphorylation in liver tumour shows therapeutic resistance to metformin. Clinically, the AMPK-PROX1 axis in human cancers is important for patient clinical outcomes. Collectively, our results demonstrate that deficiency of the LKB1-AMPK axis in cancers reactivates PROX1 to sustain intracellular BCAA pools, resulting in enhanced mTOR signalling, and facilitating tumourigenesis and aggressiveness.

The differences in learning motivation of college freshmen in Northwest China.

The study aimed to investigate the learning motivation of freshmen from a university in Northwest China, which can supply a reference for improving their learning quality and objectives. Data were collected from 800 freshmen of different majors with a learning motivation questionnaire. Differences in learning motivation between different majors, genders, regions, and students are studied. The results show that gender, seeking knowledge orientation, and material pursuit have significant effects on students' learning motivation. The gender had a significant impact on personal achievement and the only child or not had an obvious effect on material pursuit, while other factors had no obvious difference in gender, regional, and only child or not, while other factors on the gender, regional, and whether the one-child had no obvious difference. According to the results of the research, measures to improve learning motivation are proposed. Our research results provide a reference for improving learning attitude and the quality of universities.

Investigation and research on the current situation of ethics and morality of medical postgraduate supervisors / 中华医学教育探索杂志

Objective:To explore the evaluation and demand of clinical medical postgraduates for the supervisors' ethics and morality, and to explore ways to construct their ethics and morality in medical education.Methods:In the study, 2 268 clinical medical postgraduates in a medical university in Jiangsu Province were investigated with their satisfaction, compliance and suggestions. Rank sum test was carried out for the satisfaction by using SPSS 26.0, and qualitative analysis was carried out for suggestions.Results:The overall satisfaction of graduate students to the ethics and morality of supervisors was high. All the items described in the supervisors' ethics were "very consistent" more than 80%. Through qualitative analysis, the feedback were divided into six themes namely "supervision and feedback", "supervisor training", "reward and punishment system", "communication", "caring for students" and "academic guidance".Conclusion:The evaluation of clinical medical supervisors' ethics and morality is generally at a high level. The cultivation and guidance of supervisors' ethics and morality, supervision mechanism, and reward and punishment system still need to be improved.

The Relationship Between Perceived Stress, State-Trait Anxiety, and Sleep Quality Among University Graduates in China During the COVID-19 Pandemic.

The study aimed to investigate the relationship among perceived stress, state-trait anxiety, and sleep quality of graduates to provide a reference for improving their psychological status and attitude adjustment of job-searching during the COVID-19 pandemic. The research was conducted in a descriptive cross-sectional online survey between May 2020 and August 2020. The data were collected from 1,200 participants by using the personal information form prepared by the researchers in line with the literature, the Perceived Stress Scale, the State-Trait Anxiety Inventory, and the Pittsburgh Sleep Quality Index (PSQI). Among the surveyed participants, 47.67% were female, and 10.92% were medical students. The mean perceived stress, state anxiety, trait anxiety, and sleep quality were moderate and found as 31.4±6.69, 46.67±5.80, 49.45±5.54, and 5.94±2.47, respectively. The detection rates of state anxiety and trait anxiety were 48.63 and 49.50%, respectively. There was no significant difference in the detection rate of state anxiety and trait anxiety among different genders and majors (p >0.05). The detection rate of state anxiety and trait anxiety of rural family students was higher than that of urban family students (p <0.01). The score on the PSQI was positively associated with the scores on the perceived stress, state anxiety, and trait anxiety scales (p <0.001 for each model). Sleep quality was associated with increased perceived stress, state anxiety, and trait anxiety among graduates in China. Collectively, the study revealed the relationship between perceived stress, state-trait anxiety, and sleep quality among university graduates in China during the COVID-19 pandemic. Our results offer novel practical implications for all circles of the society to ensure students' health under the context of the COVID-19 epidemic.

Mg/ZrO2 Metal Matrix Nanocomposites Fabricated by Friction Stir Processing: Microstructure, Mechanical Properties, and Corrosion Behavior.

Magnesium (Mg) and its alloys have attached more and more attention because of their potential as a new type of biodegradable metal materials. In this work, AZ31/ZrO2 nanocomposites with good uniformity were prepared successfully by friction stir processing (FSP). The scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to characterize the microstructure of the composites. The mechanical properties, electrochemical corrosion properties and biological properties were evaluated. In addition, the effect of reinforced particles (ZrO2) on the microstructure and properties of the composite was studied comparing with FSP AZ31 Mg alloy. The results show that compared with the base metal (BM), the AZ31/ZrO2 composite material achieves homogenization, densification, and grain refinement after FSP. The combination of dynamic recrystallization and ZrO2 particles leads to grain refinement of Mg alloy, and the average grain size of AZ31/ZrO2 composites is 3.2 µm. After FSP, the c-axis of grain is deflected under the compression stress of shoulder and the shear stress of pin. The ultimate tensile strength (UTS) and yield strength (YS) of BM were 283 and 137 MPa, respectively, the UTS and YS of AZ31/ZrO2 composites were 427 and 217 MPa, respectively. The grain refinement and Orowan strengthening are the major strengthening mechanisms. Moreover, the corrosion resistance in simulated body fluid of Mg alloy is improved by grain refinement and the barrier effect of ZrO2.

C24-Ceramide Drives Gallbladder Cancer Progression Through Directly Targeting Phosphatidylinositol 5-Phosphate 4-Kinase Type-2 Gamma to Facilitate Mammalian Target of Rapamycin Signaling Activation.

BACKGROUND AND AIMS: The wide prevalence of chemoresistance and compromised early diagnosis of gallbladder cancer (GBC) has led to poor patient prognosis, requiring sustained efforts for the identification of effective biomarkers and therapeutic intervention. Ceramides have emerged as intracellular signaling molecules linked to tumorigenesis and therapeutic response in cancers. However, the clinical relevance of ceramides with GBC has not been investigated. APPROACH AND RESULTS: In the present study, we revealed aberrant gene expressions (e.g., serine palmitoyltransferase 1 [SPTLC1] and ceramide synthase 2 [CERS2]) of de novo ceramide biosynthesis and length-specific ceramide production in GBC tissues. Analyses of serum ceramide pattern in healthy controls, gallbladder stone, and GBC patients identified C24-Ceramide as a potential diagnostic biomarker for patients with GBC. Importantly, elevation of SPTLC1, CERS2, and its product, C24-Ceramide, was associated with tumor staging, distal metastasis, and worse prognosis. In line with this, C24 -Ceramide promoted GBC cell proliferation and migration in vitro and in vivo. Mechanistically, C24-Ceramide directly bound to phosphatidylinositol 5-phosphate 4-kinase type-2 gamma (PIP4K2C), a regulator of mammalian target of rapamycin (mTOR), to facilitate mTOR complex formation and activation. C6-Ceramide, an analogue of natural ceramide, competed with C24-Ceramide for PIP4K2C binding, thereby abrogating C24-Ceramide-mediated mTOR signaling activation and oncogenic activity. Furthermore, stimulation with C6-Ceramide significantly suppressed the proliferative and metastatic capacity of GBC cells in vitro and in vivo, which was dependent on PIP4K2C. CONCLUSIONS: Our findings highlight the clinical relevance of ceramide metabolism with GBC progression and identify C24-Ceramide as a diagnostic biomarker for GBC. We propose that PIP4K2C is indispensable for C6-Ceramide as a potential therapeutic intervention for GBC through a direct competition with C24-Ceramide.

Autophagy Activated by Peroxiredoxin of Entamoeba histolytica.

Autophagy, an evolutionarily conserved mechanism to remove redundant or dangerous cellular components, plays an important role in innate immunity and defense against pathogens, which, in turn, can regulate autophagy to establish infection within a host. However, for Entamoeba histolytica, an intestinal protozoan parasite causing human amoebic colitis, the interaction with the host cell autophagy mechanism has not been investigated. In this study, we found that E. histolytica peroxiredoxin (Prx), an antioxidant enzyme critical for parasite survival during the invasion of host tissues, could activate autophagy in macrophages. The formation of autophagosomes in macrophages treated with recombinant Prx of E. histolytica for 24 h was revealed by immunofluorescence and immunoblotting in RAW264.7 cells and in mice. Prx was cytotoxic for RAW264.7 macrophages after 48-h treatment, which was partly attributed to autophagy-dependent cell death. RNA interference experiments revealed that Prx induced autophagy mostly through the toll-like receptor 4 (TLR4)-TIR domain-containing adaptor-inducing interferon (TRIF) pathway. The C-terminal part of Prx comprising 100 amino acids was the key functional domain to activate autophagy. These results indicated that Prx of E. histolytica could induce autophagy and cytotoxic effects in macrophages, revealing a new pathogenic mechanism activated by E. histolytica in host cells.

Clinical Efficacy of Modified Danggui Niantongtang Combined with Xuanbitang in Treating Damp-heat Type Acute Gouty Arthritis / 中国实验方剂学杂志

Objective:To observe the clinical efficacy of modified Danggui Niantongtang combined with Xuanbitang in treating damp-heat type acute gouty arthritis, and investigate its effect on levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α). Method:Totally 126 patients were randomly divided into control group and observation group, with 63 cases in each group. In addition to non-medication treatment, patients in control group were given conventional western medicine treatment for 1 week, while patients in observation group were given modified Danggui Niantongtang combined with Xuanbitang for 1 week. The levels of IL-1β，IL-6，IL-8，TNF-α before and after treatment were observed. Result:The total effective rate was 79.37% in control group and 95.24% in observation group, with significant differences (P<0.05). After treatment, the scores of arthralgia, tenderness, swelling, activity restriction in both groups were significantly decreased (P<0.01), and those in observation group were lower than those in control group (P<0.05). The levels of uric acid (UA), high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR) were significantly decreased (P<0.01) after treatment, and those in observation group were lower than those in the control group (P<0.05). The levels of IL-1β，IL-6，IL-8，TNF-α were significantly decreased (P<0.01) after treatment, and those in the observation group were lower than those in the control group (P<0.05). Conclusion:Compared with conventional western medicine treatment, modified Danggui Niantongtang combined with Xuanbitang has a better efficacy in treating damp-heat type acute gouty arthritis and reducing levels of IL-1β，IL-6，IL-8，TNF-α.

Combined postoperative adjuvant transarterial chemoembolization and portal vein chemotherapy to treat patients with hepatocellular carcinoma and portal vein tumor thrombosis: a meta-analysis / 中华肝胆外科杂志

Objective:To systematically review the clinical effectiveness of combined postoperative adjuvant transcatheter arterial chemoembolization (TACE) with portal vein chemotherapy (PVC) versus TACE alone in patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT).Methods:Databases including PubMed, Embase, Cochrane Library, Medline, Web of Science, CNKI, China Biology Medicine, Wan Fang and VIP were searched from Jan 1st 2000 to Jun 30th 2019 for eligible studies on clinical effectiveness of combined postoperative adjuvant TACE with PVC versus TACE alone in patients with HCC and PVTT. The primary endpoints were overall survival (OS) and disease-free survival (DFS). The secondary endpoint was adverse events. These endpoints were evaluated by odds ratio ( OR) and 95% confidence interval ( CI) using Review Manager 5.3 software. Results:Nine studies with 642 patients were enrolled in this meta-analysis. There were 323 patients in the TACE group and 319 patients in the TACE plus PVC group. The pooled OR for the 1-, 2-, and 3-year OS were all significantly better in the TACE plus PVC group than the TACE group (1-year OS, OR=2.20, 95% CI: 1.53-3.17; 2-year OS, OR=2.44, 95% CI: 1.69-3.53; 3-year OS, OR=2.30, 95% CI: 1.52-3.46) (all P<0.05). Similarly, significantly better results were observed in the pooled OR for the 1-, 2-, and 3-year DFS (1-year DFS, OR=2.56, 95% CI: 1.70-3.86; 2-year DFS, OR=2.27, 95% CI: 1.19-4.32; 3-year DFS, OR=3.03, 95% CI: 1.55-5.92) (all P<0.05). There were no significant differences in the incidences of adverse events between the two groups (all P>0.05). Conclusion:Postoperative adjuvant TACE combined with PVC for patients with HCC and PVTT was safe and effective, and was significantly better than TACE alone in long-term prognosis. Large-scale, multi-center, prospective studies are needed to support the conclusion.

Cholesterol depletion sensitizes gallbladder cancer to cisplatin by impairing DNA damage response.

Gallbladder cancer (GBC) is the common malignancy of the bile tract system with extremely poor clinical outcomes, owing to its metastatic property and intrinsic resistance to the first-line drugs. Although it is well-established that cholesterol abnormity contributes to gallstone formation, a leading risk factor for GBC, the link of cholesterol homeostasis with GBC has not been investigated. The present study systematically examined the genes implicated in cholesterol homeostasis, and revealed altered gene expressions of de novo cholesterol biosynthesis and sterol sulfonation (SULT2B1), reduced bile acid synthesis (CYP7B1 and CYP39A1) and impaired sterol efflux (ABCA1, ABCG5, LCAT, and CETP) in GBC tissues. Suppression of cholesterol biosynthesis by lovastatin inhibited GBC cell proliferation possibly through attenuating the DNA repair process. Further investigation revealed lovastatin sensitized GBC cells to cisplatin-induced apoptosis and suppressed the activation of CHK1, CHK2, and H2AX during DNA damage response. By using chemically distinct statins, HMGCR depletion or supplementing mevalonate, the product of HMGCR, we showed the inhibitory effects on DNA repair process of lovastatin were due to the blockage of the mevalonate pathway. Subcutaneous xenograft mice model suggested lovastatin promoted the therapeutic efficacy of cisplatin, and significantly prolonged the survival times of tumor-bearing mice. Moreover, HMGCR ablation repressed tumor growth in vivo, which can be rescued partially by restored expression of HMGCR, suggesting the on-target effects of lovastatin. Therefore, our study provides the clinical relevance of cholesterol homeostasis with GBC progression, and highlights a novel intervention of combined use of lovastatin and cisplatin for GBC.

An E. coli-produced single-chain variable fragment (scFv) targeting hepatitis B virus surface protein potently inhibited virion secretion.

Hepatitis B virus (HBV) envelopes as well as empty subviral particles carry in their lipid membranes the small (S), middle (M), and large (L) surface proteins, collectively known as hepatitis B surface antigen (HBsAg). Due to their common S domain all three proteins share a surface-exposed hydrophilic antigenic loop (AGL) with a complex disulfide bridge-dependent structure. The AGL is critical for HBV infectivity and virion secretion, and thus represents a major target for neutralizing antibodies. Previously, a human monoclonal antibody (mAb) targeting a conformational epitope in the AGL, IgG12, exhibited 1000-fold higher neutralizing activity than hepatitis B immune globulin (HBIG). Here we designed a single-chain variable fragment (scFv) homolog of IgG12, G12-scFv, which could be efficiently produced in soluble form in the cytoplasm of E. coli SHuffle cells. Independent in vitro assays verified specific binding of G12-scFv to a conformational S epitope shared with IgG12. Despite 20-fold lower affinity, G12-scFv but not an irrelevant scFv potently neutralized HBV infection of susceptible hepatoma cells (IC50 = 1.8 nM). Strikingly, low concentrations of G12-scFv blocked virion secretion from HBV producing cells (IC50 = 1.25 nM) without disturbing intracellular viral replication, whereas extracellular HBsAg was reduced only at >100-fold higher though still nontoxic concentration. The inhibitory effects correlated with S binding specificity and presumably also G12-scFv internalization into cells. Together these data suggest G12-scFv as a highly specific yet easily accessible novel tool for basic, diagnostic, and possibly future therapeutic applications.

VCAM-1-mediated neutrophil infiltration exacerbates ambient fine particle-induced lung injury.

BACKGROUND: Fine ambient particle matter (PM2.5) induces inflammatory lung injury; however, whether intratracheal administration of PM2.5 increases pulmonary polymorphonuclear leukocyte (PMN) infiltration, the mechanism of infiltration, and if these cells exacerbate PM2.5-induced lung injury are unknown. METHODS: Using 32,704 subjects, the association between blood PMNs and ambient PM2.5 levels on the previous day was retrospectively analyzed. Neutropenia was achieved by injecting mice with PMN-specific antibodies. Inhibition of PMN infiltration was achieved by pretreating PMNs with soluble vascular cell adhesion molecule-1 (sVCAM-1). The effects of PMNs on PM2.5-induced lung injury and endothelial dysfunction were observed. RESULT: Short-term PM2.5 (> 75 µg/m3 air) exposure increased the PMN/white blood cell ratio and the PMN count in human peripheral blood observed during routine examination. A significant number of PM2.5-treated PMNs was able to bind sVCAM-1. In mice, intratracheally-instilled PM2.5 deposited in the alveolar space and endothelial cells, which caused significant lung edema, morphological disorder, increased permeability of the endothelial-alveolar epithelial barrier, and PMN infiltration with increased VCAM-1 expression. Depletion of circulatory PMNs inhibited these adverse effects. Replenishment of untreated PMNs, but not those pretreated with soluble VCAM-1, restored lung injury. In vitro, PM2.5 increased VCAM-1 expression and endothelial and epithelial monolayer permeability, and promoted PMN adhesion to, chemotaxis toward, and migration across these monolayers. PMNs, but not those pretreated with soluble VCAM-1, exacerbated these effects. CONCLUSION: VCAM-1-mediated PMN infiltration was essential for a detrimental cycle of PM2.5-induced inflammation and lung injury. Results suggest that drugs that inhibit PMN function might prevent acute deterioration of chronic pulmonary and cardiovascular diseases triggered by PM2.5.

Clinical Efficacy of Modified Bingtitang in Treatment of Type 2 Diabetes Mellitus and Effect on Pancreas Islet Function / 中国实验方剂学杂志

Objective:To investigate the clinical efficacy of modified Bingtitang in treatment of type 2 diabetes mellitus(T2DM) and its effect on pancreas islet function. Method:A total of 108 patients with T2DM were divided into two groups according to the digital number table method, with 54 cases in each group. The control group were given routine therapy of diabetic diet, proper exercise and blood sugar control, while the treatment group were orally given traditional Chinese medicine (TCM) and modified Bingtitang in addition to the therapy of the control group. The blood sugar, pancreas islet function-related indexes, TCM syndrome score, serum retinol binding protein 4 (RBP4) and Betatrohin levels were compared between two groups before and after treatment. The total effective rate was also compared. Result:After treatment, the fasting blood glucose (FPG), glycated hemoglobin (HbA1c), blood glucose variation coefficient (CV-FPG), insulin resistance index (HOMA-IR) of the treatment group were lower than those of control group (PΔI30/ΔG30)of treatment group were higher than those of the control group (PPPPConclusion:In addition to the routine treatment, modified Bingtitang can effectively control blood sugar, improve pancreas islet function, and alleviate TCM syndromes, with a significant effect on T2DM. Its mechanism may be related to the regulation of serum RBP4 and Betatrohin levels.

Molecular and biochemical characterization of key enzymes in the cysteine and serine metabolic pathways of Acanthamoeba castellanii.

BACKGROUND: Acanthamoeba spp. can cause serious human infections, including Acanthamoeba keratitis, granulomatous amoebic encephalitis and cutaneous acanthamoebiasis. Cysteine biosynthesis and the L-serine metabolic pathway play important roles in the energy metabolism of Acanthamoeba spp. However, no study has confirmed the functions of cysteine synthase (AcCS) in the cysteine pathway and phosphoglycerate dehydrogenase (AcGDH) or phosphoserine aminotransferase (AcSPAT) in the non-phosphorylation serine metabolic pathway of Acanthamoeba. METHODS: The AcCS, AcGDH and AcSPAT genes were amplified by PCR, and their recombinant proteins were expressed in Escherichia coli. Polyclonal antibodies against the recombinant proteins were prepared in mice and used to determine the subcellular localisation of each native protein by confocal laser scanning microscopy. The enzymatic activity of each recombinant protein was also analysed. Furthermore, each gene expression level was analysed by quantitative PCR after treatment with different concentrations of cysteine or L-serine. RESULTS: The AcCS gene encodes a 382-amino acid protein with a predicted molecular mass of 43.1 kDa and an isoelectric point (pI) of 8.11. The AcGDH gene encodes a 350-amino acid protein with a predicted molecular mass of 39.1 kDa and a pI of 5.51. The AcSPAT gene encodes a 354-amino acid protein with a predicted molecular mass of 38.3 kDa and a pI of 6.26. Recombinant AcCS exhibited a high cysteine synthesis activity using O-acetylserine and Na2S as substrates. Both GDH and SPAT catalysed degradation, rather than synthesis, of serine. Exogenous L-serine or cysteine inhibited the expression of all three enzymes in a time- and dose-dependent manner. CONCLUSIONS: This study demonstrated that AcCS participates in cysteine biosynthesis and serine degradation via the non-phosphorylation serine metabolic pathway, providing a molecular basis for the discovery of novel anti-Acanthamoeba drugs.