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Ferroelectricity in two-dimensional (2D) systems generally arises from phonons and has been widely investigated. On the contrary, electronic ferroelectricity in 2D systems has been rarely studied. Using first-principles calculations, the ferroelectric behavior of the buckled blue SiSe monolayer under strain are explored. It is found that the direction of the out-of-plane ferroelectric polarization can be reversed by applying an in-plane strain. And such polarization switching is realized without undergoing geometric inversion. Besides, the strain-triggered polarization reversal emerges in both biaxial and uniaxial strain cases, indicating it is an intrinsic feature of such a system. Further analysis shows that the polarization switching is the result of the reversal of the magnitudes of the positive and negative charge center vectors. And the variation of buckling is found to play an important role, which results in the switch. Moreover, a non-monotonic variation of band gap with strain is revealed. Our findings throws light on the investigation of novel electronic ferroelectric systems.

Background: With improving living standards, the incidence of cervical spondylotic myelopathy (CSM) has become increasingly high., Objective: The study aims to explore the effect of diversified health-promoting models on rehabilitation exercises in patients with CSM after an operation., Method: This was a randomized controlled trial, wherein 107 patients with CSM treated by neurosurgery were selected as the subjects. Of those, 52 patients in the control group adopted the conventional health-promoting model, while the remaining 55 patients in the intervention group adopted diversified health-promoting models. The effect of rehabilitation exercises in the two groups was evaluated according to the self-efficacy rehabilitation outcome scale, grip strength measurement of the affected limb, and Barthel index., Results: At Day 3 post-operation and before discharge, the self-efficacy management of rehabilitation exercises in the intervention group was better than that of the control group (P< 0.05). The grip strength measurement of the affected limb, Japanese Orthopedic Association score of the cervical vertebra, and Barthel index of the two groups at Day 3 post-operation were lower than before the intervention and were not statistically significant (P> 0.05). However, these three items before discharge were improved when compared with those of before intervention and were statistically significant (P< 0.05)., Conclusion: Postoperative rehabilitation exercises guided by the diversified health-promoting models for patients with CSM can improve the patients' self-efficacy management ability in rehabilitation exercises, help improve grip strength, and promote the recovery of cervical vertebra function, thereby improving the patients' quality of life.

Background: The association of metabolic syndrome (MetS) with depression has been previously reported; however, the results are ambiguous due to imbalanced confounding factors. Propensity score-based analysis is of great significance to minimize the impact of confounders in observational studies. Thus, the current study aimed to clarify the influence of MetS on depression incidence in the U.S. adult population by using propensity score (PS)-based analysis., Methods: Data from 11,956 adults aged 20-85 years from the National Health and Nutrition Examination Survey (NHANES) database between 2005 and 2018 were utilized. Using 1:1 PS matching (PSM), the present cross-sectional study included 4,194 participants with and without MetS. A multivariate logistic regression model and three PS-based methods were applied to assess the actual association between MetS and depression incidence. Stratified analyses and interactions were performed based on age, sex, race, and components of MetS., Results: After PSM, the risk of developing depression in patients with MetS increased by 40% in the PS-adjusted model (OR = 1.40, 95% confidence interval [CI]: 1.202-1.619, P < 0.001), and we could still observe a positive association in the fully adjusted model (OR = 1.37, 95% CI: 1.172-1.596, P < 0.001). Regarding the count of MetS components, having four and five conditions significantly elevated the risk of depression both in the PS-adjusted model (OR = 1.78, 95% CI: 1.341-2.016, P < 0.001 vs. OR = 2.11, 95% CI: 1.626-2.699, P < 0.001) and in the fully adjusted model (OR = 1.56, 95 CI%: 1.264-1.933, P < 0.001 vs. OR = 1.90, 95% CI: 1.458-2.486, P < 0.001). In addition, an elevation in MetS component count was associated with a significant linear elevation in the mean score of PHQ-9 (F =2.8356, P < 0.001). In the sensitivity analysis, similar conclusions were reached for both the original and weighted cohorts. Further interaction analysis revealed a clear gender-based difference in the association between MetS and depression incidence., Conclusion: MetS exhibited the greatest influence on depression incidence in US adults, supporting the necessity of early detection and treatment of depressive symptoms in patients with MetS (or its components), particularly in female cases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Zhou, Shao, Hu, Wen and Xia.)

The thermal stability of enzymes dramatically limits their application in the industrial field. Based on the crystal structure, we conducted a semi-rational design according to the B-factor and free energy values to improve the stability of dextranase from Streptococcus mutans (SmdexTM). The B-factor values of Asn102, Asn503, Asp501 and Asp500 were the highest predicted by B-FITTER. Then Rosetta was used to simulate the saturation mutations of Asn102, Asn503, Asp501 and Asp500. The mutated amino acid was designed according to the change of acG. The results showed that the thermal stability of N102P, N102C, D500G, and D500T was improved, and the half-lives of N102P/D500G and N102P/D500T at 45 °C were increased to 3.14 times and 2.44 times, respectively. Analyzing the interaction of amino acids by using Discovery Studio 4.5, it was observed that the thermal stability of dextranase was improved due to the increase in hydrophobicity and the number of hydrogen bonds of the mutant enzyme. The catalytic efficiency of N102P/D500T was increased. Compared with the hydrolyzed products of SmdexTM, the mutant enzymes do not change the specificity of hydrolysates., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Improving enzyme stability is very important for enzyme applications. Structural modification is a reliable and effective method to improve the characteristics of protein. By artificially extending the C-terminus, 6 domain modification variants of different sizes were constructed, and a new enzyme species with high stability was obtained. Experimental results affirmed that high stability can be achieved by decreasing the degree of domain freedom. The optimum temperatures of domain modification variants were improved by 10 °C compared with the original enzyme. Specifically, compared with the original enzyme, the half-life of the variant dexYG-fdx (D-F) was increased to 280% under 35 °C and 200% under 45 °C, and the pH tolerance range was wider. Further structural simulations and molecular docking studies provided a reasonable explanation (The increased domain reduced the degree of freedom of the enzyme terminal to some extent) for this variant to increase stability and produce dextran. This study can provide valuable information for increasing the characteristics of recombinant dextransucrase., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Bioglycosylation is an efficient strategy to improve biological activities and physicochemical properties of natural compounds to develop structural modifications of drugs. In this study, an N555 residue was identified as a candidate for site-directed mutagenesis through sequence alignment with GTF180ΔN. Caffeic acid phenethyl ester (CAPE) was used as an acceptor substrate. Two generated mutants, N555Q and N555E, demonstrated significant specificity of distribution of products. Under identical conditions, the conversion rates of diglycoside products (CAPE-2G) generated by the N555E (80.8%) and N555Q (84.5%) mutants were 3.30- and 3.46-fold higher than those generated by the original enzyme (24.4%). The structural simulation results demonstrated that a new hydrogen bond was formed between the N555 residue and CAPE, and the N555 residue was closely related to substrate elongation. These results provide a reference for subsequent studies. Suitable mutants for transfer of diglycosides have important application potential in the food and pharmaceutical industries.

The structural modification of polysaccharides directly affects their physicochemical properties and applications. Dextran, a chained polysaccharide, consists of multiple d-glucose molecules with repetitive structures. In this study, the physicochemical properties of oxidized dextran (DO) at different concentrations of NaClO/NaBr and H 2 O 2 were compared. The results showed that NaClO/NaBr oxidation is more conducive to the formation of carboxyl groups. Oxidized dextran with NaClO/NaBr (DOB) showed good iron (III) chelating ability, and the DOB‑iron (III) complex (DOBIC) had an iron content of 28.31%. According to structural analysis, NaClO/NaBr (2 g/100 g of active chlorine) and H 2 O 2 (4 g/100 g), respectively, oxidize the C1 and C2 hydroxyl groups of dextran to carboxyl groups and open the ring when DO and iron have the strongest chelation ability. The complex is indeed a chelate iron complex, and iron core is composed of iron oxyhydroxide or the β-FeOOH mineral polymorph. These results indicate that DOBIC is expected to be a good iron supplement or food additive to strengthen iron., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Polysaccharide-modified flocculants as natural polymeric flocculants are receiving increased attention in the field of water treatment. In this study, a novel high-efficiency and ecofriendly flocculant was synthesized using dextran and chitosan. The flocculant-production method was based on a microwave-heating-initiated graft reaction. Results of Fourier transform infrared spectroscopy, nuclear magnetic resonance imaging, X-ray diffraction, elemental analysis, thermogravimetric analysis, and field-emission scanning electron microscopy confirmed that the grafting was successful. The influences of temperature, flocculant dosage, and pH on flocculation efficiency were investigated. Results indicated that 93.6% of the kaolin solid suspended particles were removed by the flocculant. Previous studies on the flocculation mechanism have shown that flocculation comprises adsorption bridging, charge neutralization, and sweeping flocculation. All these findings indicated the broad prospects of the improved dextran in treating industrial wastewater and developing novel high-performance flocculants., (Copyright © 2019. Published by Elsevier B.V.)

Bioglycosylation is an efficient strategy to improve the biological activity and physicochemical properties of natural compounds for therapeutic drug development. In this study, two caffeic acid phenethyl ester (CAPE) glucosides (G-CAPE and 2G-CAPE) were synthesized by transglycosylation with dextransucrase from Leuconostoc mesenteroides 0326 with CAPE as an acceptor and sucrose as a donor. The products were purified and the structures were characterized. The physicochemical properties, anti-inflammatory activity, and cytotoxicity of the two CAPE glucosides were measured. The water solubility of G-CAPE and 2G-CAPE is 35 and 90 times higher, respectively, than that of CAPE. Compared to CAPE, the monoglycoside product showed superior anti-inflammatory effects, and its inhibition rate of NO, IF-6, and TNF-α is 93.4%, 76.81%, and 56.58% in RAW 264.7 macrophages, respectively, at 20 μM. Also, the cytotoxicity of both products was significantly improved. These glycosylation-modified CAPEs circumvent some of the flaws in CAPE application in anti-inflammatory drugs.

Dextran produced by dextransucrase hold strong potential for industrial applications. The exact determinants of the linkage specificity of glucansucrase enzymes have remained largely unknown. Previous studies have investigated the relationships between structure and linkage specificity of the dextransucrase DSR from Leuconostoc mesenteroides by the site-directed mutagenesis of the catalytic pocket. The glycosidic linkage of dextran produced by mutant enzymes changed slightly by 3% to 20%. The mutagenesis dextransucrases were constructed by inserting an amino acid into a catalytic pocket to investigate the product specificities of dextransucrase thoroughly. The sequence and structural analysis of glycoside-hydrolase family 70 enzymes led to two sequences (Motif II and Motif IV) being targeted, which were inserted by saturation mutagenesis and simultaneously recombined between A552 and V553, D662, and S663. Variants with catalytic activity were screened of the library, which synthesizes high molecular weight α-glucans with different proportions of α(1-4) linkages, which ranges from 0% to 52%. Mutant sequence analysis, biochemical characterization, and molecular modeling studies revealed the mechanism of product specificities. The mutant dextransucrase, which synthesizes hyperbranched dextran, were obtained by the novel mutagenesis method. The different properties of dextran provide the foundation for subsequent studies and application., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Dextransucrase (DSR, EC2.4.5.1) from Leuconostoc mesenteroides 0326 which catalyzes sucrose to produce dextran, are popularly used in food and medicine industries. However, its poor kinetic stability especially at higher temperatures is a limiting factor for developing industrial applications. The aim of this study is to improve the enzyme activity and thermal stability of dextransucrase by single, double and triple mutations of proline and lysine. In this work, Pro-473, Pro-678, and Pro-856 were selected as engineering targets and individually replaced with serine. Lys-378, Lys-725, and Lys-955 were replaced with threonine, respectively. Mutant P473S/P856S (MW: 170kDa) was selected as the highest enzymatic activity mutant from fourteen mutants. Specifically, the mutant P473S/P856S showed a significant increase in thermal inactivation with a 7.4-fold increase in half-life at 35°C and a 2-fold increase in catalytic efficiency compared with the wild-type. The results of structural simulation are demonstrated that the new intramolecular hydrogen bonds in mutated enzymes increased structural stability, thereby increasing the thermal stability. The thermal stable mutants have an enormous application potential in food and pharmaceutical industry., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Dextran is an interesting starting material to design new functional polymers by chemical modification. Potential applications of dextran in water treatment should be increasingly developed and the structure properties of dextran derivatives should be focused on. In the study, dextran ester was synthesized through the esterification reaction of hydroxyl. The structure and some physicochemical properties of synthesized dextran ester were characterized and further analyzed. And we found that dextran ester could exert desirable flocculation performance in both kaolin and sugarcane juice under acidic conditions but not lower than pH 4. Our obtained flocculant was readily-available, sustainable and environmental friendly, which is suitable for juice flocculation process., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Dextrans with distinct molecular size and structure are increasingly being used in the food and pharmaceutical industries. Dextran is produced by dextransucrase (DSR, EC2.4.5.1), which is produced by Leuconostoc mesenteroides. DSR belongs to glycosyl hydrolase family (GH70) and synthesizes branched α-glucan (dextran) with both 5% α(1-3) and 95% α(1-6) glycosidic linkages. The DSR gene dex-YG (Genebank, Accession No. DQ345760) was cloned from the wild strain Leuconostoc mesenteroides 0326. This study generated a series of C-terminally truncated variants of dextransucrase and substituting the amino-acid residues in the active site of DSR. With shorter length of DSR, its polysaccharide-synthesizing capability was impaired heavily, whereas oligosaccharide (acting as prebiotics)-synthesizing capability increased significantly, efficiently producing special sizes of dextran. All truncated mutant enzymes were active. Results demonstrated that the catalytic domain dextransucrase was likely in 800 aa or less. Based on the three-dimensional structure model of dextransucrase built through homology modeling methods, the DSR and its mutants with the acceptor substrate of maltose and donor substrate of sucrose were studied by molecular-docking method. Substituting these amino-acid residues significantly affected enzyme activities. Compared with the wild-type dextran, mutant enzymes catalyzed the synthesis of a-glucan with 1-9% α(1-3) and 90-98% α(1-6) branching linkages. Some mutants introduced a small amount of α(1-4) linkages and α(1-2) linkages. This strategy can be effectively used for the rational protein design of dextransucrase., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Metabolomics was applied to the liquid chromatography-mass spectrometry urinary metabolic profile of type 2 diabetes (T2DM) mice treated with mulberry 1-deoxynojirimycin (DNJ). The serum biochemical indicators related to T2DM like blood glucose, insulin, triglyceride, total cholesterol, nitrogen, malondialdehyde, and creatinine decreased significantly in the treated group. The histopathological changes in liver cells were marked by deformations and disruptions in central area of nuclei in DM mice, whereas DNJ treatment recovered regular liver cells with normal nuclei. Most of the metabolites of T2DM were significantly different from healthy controls in the bulk data generated. The level of 16 metabolites showed that the diabetic group was closer to the healthy group as the DNJ treatment time prolonged. Moreover, DNJ inhibited the activity of glucosidase on glucose, lipid, and amino acid metabolism. Our results showed the mechanism of DNJ treatment of T2DM and could fetch deep insights into the potent metabolite markers of the applied antidiabetic interventions.

Objective: To explore the feasibility of passage, cryopreservation, and recovery of osteoclasts in order to develop new techniques facilitating osteoclast research., Methods: Passage of osteoclasts: adult male SD rat(SPF grade, weight of 250 g) was sacrificed and the abdominal aorta was exposed for blood draw. Monocytes isolated from peripheral circulation was treated with RANKL and M-CSF for 2 weeks. After formation of osteoclasts, they were trypsinized with pipetting, centrifuged, re-suspended with α-MEM containing RANKL and M-CSF, and cultured in 6 well-plates and 35 mm culture dishes. Freezing of osteoclasts: trypsinized osteoclasts were centrifuged and resuspended with DMSO, FBS, α-MEM (1:2:7), and were stored in liquid nitrogen(-196 °C). Recovery of osteoclasts: frozen osteoclasts were taken out of liquid nitrogen tank and thawed quickly at 37 °C in water bath. After wash with PBS, the cells were resuspended with α-MEM containing RANKL and M-CSF, and were cultured in 6 well dishes and 35 mm culture dishes. Meanwhile, cells were checked with inverted phase contrast microscope and observed in the live cell station for real time imaging. TRAP staining was performed 3 days after plating., Results: Trypsinization together with pipetting and shaking can detach the adherent osteoclasts, and the resuspended cells can be used for passage and storage in liquid nitrogen. The passaged cells became fully attached to the culture dishes in 2 hours, and the multinucleated feature could be clearly seen. The osteoclasts recovered from liquid nitrogen could completely spread out for 2 to 3 hours so that the multinucleated cells were clearly seen. These cells were still TRAP positive., Conclusions: Although osteoclasts strongly adhere to the bottom of culture dishes, a large majority of the osteoclasts can be detached after appropriate digestion with trypsin, pipetting and shaking. These cells can be used for passage and cryopreservation. After recovering from liquid nitrogen, these cells still preserve the viability and the feature of osteoclasts. The results provide a new and powerful tool for future study of osteoclast biology., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

Dextranase can hydrolyze dextran to low-molecular-weight polysaccharides, which have important medical applications. In the study, dextranase-producing strains were screened from various soil sources. The strain H6 was identified as Talaromyces pinophilus by a standard ITS rDNA analysis. Crude dextranase was purified by ammonium sulfate fractionation and Sepharose 6B chromatography, which resulted in a 6.69-fold increase in the specific activity and an 11.27% recovery. The enzyme was 58 kDa, lower than most dextranase, with an optimum temperature of 45 °C and an optimum pH of 6.0, and identified as an endodextranase. It was steady over a pH range from 3.0 to 10.0 and had reasonable thermal stability. The dextranase activity was increased by urea, which enhanced its activity to 115.35% and was conducive to clinical dextran production. Therefore, T. pinophilus H6 dextranase could show its superiority in practical applications.

Dextransucrase (EC2.4.5.1) from strain Leuconostoc mesenteroides 0326, which synthesizes dextran and oligosaccharides, which act as prebiotics, are popularly used in such industries as food and medicine. A novel dextransucrase efficient in synthesizing oligosaccharides was designed. We constructed the truncation mutant DSR-S1-ΔA (residues 1-3087bp) by deleting the 1494bp fragment of the C-terminal. The novel enzyme (MW: 110kDa) loss activity, when sucrose was used as only substrate. After adding an acceptor, DSR-S1-ΔA was fully activated but with heavily impaired polysaccharide synthesis ability. Instead, the enzyme produced a large amount of oligosaccharides. DSR-S1-ΔA showed transglycosylation for synthesizing more oligosaccharides of lower degree of polymerization (DP) with different acceptors, and it also improved the selection range of dextransucrase acceptor response to acceptors. The enzyme developed in this study can be applied in glycodiversifcation studies., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Polysaccharide-modified flocculant is a notable material in the field of wastewater treatment. Synthesis of biopolysaccharide derivatives as eco-friendly flocculants is remarkably desired for environmental protection. This work presents an efficient flocculant synthesized through copolymerization of acrylamide, sodium acrylate (AS), and dextran. Physicochemical properties of the flocculant were evaluated. Process parameters of coal-washing wastewater flocculation were tested using Response Surface Method. The application of graft polymers exhibited efficient flocculation performance at low level of flocculant dosage in alkalescent environment. The improved dextran contributes to handle industrial effluent and sanitary sewage., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Cancer immunotherapy has made an extraordinary journey from bench to bedside. Blocking the interactions between programmed cell death protein 1 (PD-1) and its ligand, PD-L1, has emerged as a promising immunotherapy for treating cancer. Here, we review the development of drugs targeting the PD-1/PD-L1 pathway. We discuss the monoclonal antibodies (mAbs) approved or in clinical trials, peptides and patented small molecules developed against this pathway. Such compounds have the potential to treat cancer as well as chronic virological diseases. We also detail PD-1/PD-L1 interactions, an understanding of which will be useful for the rational design of small-molecule therapeutics that disrupt the PD-1/PD-L1 pathway. It is likely that more mAbs targeting the PD-1/PD-L1 pathway will be approved for the treatment of a range of cancers. By contrast, it is likely to be more difficult to successfully develop small molecules or peptides and for them to reach the clinic., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: To investigate the anti-tumor activity and molecular mechanism of Tonglian Decoction (, TLD) on esophageal carcinoma Eca109 cells., Methods: Eca109 cells were treated with TLD and its separated formulae, including the clearing-heat and detoxification formula (Q), activating-blood and promoting-qi formula (H) and nourishing-yin and blood formula (Z). Cell proliferation was measured using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, cell morphology was observed using a microscope, the cell cycle was measured using flow cytometry and the activity of the nuclear factor-kappa B (NF-κB) signal pathway was detected by Western blot., Results: The half maximal inhibitory concentrations of TLD, Q and H were 386, 771 and 729 mg/L, respectively. TLD, Q and H significantly inhibited cell proliferation, with 69.43%, 60.84% and 61.90% of treated cells in the G phase of the cell cycle. The percentage of cells in S phase increased significantly after treatment with TLD, Q, and H compared with the control group (P<0.05), and TLD showed the strongest effect. Z had no influence on the cell cycle compared with the control group (P>0.05). Western blot detection indicated slight differences in the inhibition of the NF-κB pathway by the different formulae. TLD formula strongly inhibited IKKβ, NF-κB, interleukin-6 and tumor necrosis factor-α expression compared with the control group., Conclusions: TLD inhibited Eca109 cell proliferation by arresting cells in S phase. The possible mechanism might be related to inhibiting the NF-κB transduction cascade. The combination of the herbs found in the three separate formulae, H, Q and Z, work synergistically in TLD to produce the inhibitory effects of TLD treatment on Eca109 proliferation.

Objective: To explore the association of insulin resistance and β cell function with lipid metabolism in middle-aged and elderly Hui and Han populations., Methods: A total of 1000 subjects age over 40 years were recruited from five urban communities in Yinchuan and Wuzhong cities of Ningxia. The composition ratio between Hui and Han nationality was 1:2. A questionnaire-based survey was performed. Physical examinations were carried out to measure the height, body mass, waistline, and hipline. The levels of triglyceride (TG), total cholesterol (TC), blood uric acid (BUA), fasting blood glucose and insulin were measured. The boby mass index (BMI), waist-hip ratio (WHR), and secretion related index including insulin resistance index (IR), insulin sensitivity index (IAI), and beta cell function index (HBCI) were calculated., Results: The BMI, WHR, IAI, HBCI, and the prevalence rate of diabetes in Hui nationality were significantly higher than those in Han nationality (P<0.01). The levels of BUA, fasting blood glucose, TC, and IR in Han nationality were significantly lower than those in Hui nationality (P<0.01). In Hui populations, TG, BMI, WHR, and BUA were positively correlated with IR (r=0.234, r=0.193, r=0.143, and r=0.129, respectively; P<0.01) and were negatively correlated with IAI (r=-0.234, r=-0.193, r=-0.143, r=-0.129, respectively; P<0.01), whereas TC was negatively correlated with HBCI (r=-0.169, P<0.01). In Han populations, TC, TG, BMI, WHR, and BUA were positively correlated with IR (r=0.140, r=0.257, r=0.288, r=0.163, r=0.104, P<0.01) and negatively correlated with IAI (r=-0.140, r=-0.257, r=-0.288, r=-0.163, and r=-0.104, P<0.01), whereas BMI was negatively correlated with HBCI (r=-0.111, P<0.01). After the influential factors such as gender, nationality, and age were adjusted, the TC, TG, BMI, WHR, BUA levels were positively correlated with IR (r=0.109, r=0.256, r=0.253, r=0.139, and r=0.142, P<0.01) and negatively correlated with IAI (r=-0.109, r=-0.256, r=-0.253, r=-0.139, and r=-0.142, P<0.01). TC and BMI were negatively correlated with HBCI (r=-0.113, r=-0.086, P<0.01). TG and BMI were independently associated with IR and IAI (r=0.218, r=0.182, r=-0.218, r=-0.182), while TC and BMI were independently associated with HBCI (r=-0.113, r=-0.086)., Conclusions: The distributions of TC, TG, BMI, WHR, BUA, IR, IAI, and HBCI differ between Han and Hui populations. The development of insulin resistance is closely related with the increased levels of TC, TG, BMI, WHR, and BUA. However, the HBCI increases with the increased level of TC and BMI. TG and BMI may be related with insulin resistance. Also, TC and BMI may affect the secretion function of β cells.

Metalloproteins have attracted momentous attentions for the treatment of many human diseases, including cancer, HIV, hypertension, etc. This article reviews the progresses that have been made in the field of drug development of metalloprotein inhibitors, putting emphasis on the targets of carbonic anhydrase, histone deacetylase, angiotensin converting enzyme, and HIV-1 integrase. Many other important metalloproteins are also briefly discussed. The binding and coordination modes of different marketed metalloprotein inhibitors are stated, providing insights to design novel metal binding groups and further novel inhibitors for metalloproteins.

Several studies have indicated that a caloric restriction mimetic or treatment for type 2 diabetes may reverse brain aging. Therefore, we investigated the effect of 1-deoxynojirimycin (DNJ), an alkaloid acting as an inhibitor of α-glucosidase, on age-related behavioral and biochemical changes. SAMP8 mice were randomly assigned to a control group labeled "old" or to the 10- or 20-mg/kg/day DNJ groups. The mice in the DNJ groups were administered DNJ orally from 3 to 9 months of age, and then, a "young" control group was added to analyze the age effect. The old controls exhibited significant declines in sensorimotor ability, open-field anxiety, spatial and nonspatial memory abilities, and age-related biochemical changes, including decreased serum insulin level; increased levels of insulin-like growth factor 1 receptor, presynaptic protein synaptotagmin-1, and astrocyte activation; and decreased levels of insulin receptor, brain-derived neurotrophic factor, presynaptic protein syntaxin-1, and acetylation of histones H4 at lysine 8 in the dorsal hippocampus. Significant correlations exist between the age-related behavioral deficits and the serological and histochemical data. Chronic DNJ treatment alleviated these age-related changes, and the 20-mg/kg/day DNJ group showed more significant improvement. Thus, DNJ may have the potential to maintain successful brain aging.

Objective. The purpose of the study was to elucidate the molecular mechanism of tenacissoside H (TDH) inhibiting esophageal carcinoma infiltration and proliferation. Methods. In vitro, EC9706 cells were treated with TDH. Cells proliferation and cell cycle were assayed. PI3K and NF-κB mRNAs expression were determined by real time PCR. In vivo, model of nude mice with tumor was established. Mice were treated with TDH. Inhibition ratio of tumor volume was calculated. PCNA expression was examined. Protein expression in PI3K/Akt-NF-κB signaling pathway was determined. Results. In vitro, TDH significantly inhibited cells proliferation in a time-and-dose-dependent manner. TDH arrested the cell cycle in S phase and significantly inhibited PI3K and NF-κB mRNA expression, compared with blank controlled group (P < 0.05). In vivo, TDH strongly inhibits tumor growth and volume. PCNA expression was significantly decreased after treatment of TDH. TDH downregulated proteins expression in PI3K/Akt-NF-κB transduction cascade (P < 0.05). Conclusion. TDH inhibited esophageal carcinoma infiltration and proliferation both in vitro and in vivo. The anticancer activity has relation to arresting the cell cycle at the S phase, inhibited the PCNA expression of transplanted tumors in nude mice, and regulated the protein expression in the PI3K/Akt-NF-κB transduction cascade.

By using modified Levins and Petraitis formulae, this paper determined the niche breadth and niche overlap of the phytoplankton's dominant species in Dianshan Lake of East China, and analyzed the relationships between the niche breadth and niche overlap and the density and dominance of the dominant species. The niche breadth and niche overlap of the dominant species differed in different periods, and different dominant species had different adaptive capacity to the environmental factors. Based on their niche breadth in different seasons, the dominant species in the Lake could be classified into four groups, among which, Chroomonas acuta and Chlorella vulgaris had broader niche, more quantity, wider distribution, and better use of environmental resources. During cyanobacterial blooms, the niche overlap among Cyanophyta species was comparatively higher, Microcystis aeruginosa had broader niche breadth, but other species showed lower niche breadth. Correlation analysis showed that the dominance of the dominant species in different seasons had significant correlation with their niche breadth, and the dominant species density had significant correlation with their niche overlap.

Based on the investigation data of phytoplankton in Dianshan Lake from May to October in 2009, the characteristics of phytoplankton community and the dominant species succession are studied. The results show that Cyanophyta and Chlorophta are the main taxa. Cyanophyta is dominant in cell abundance and Chlorophta is dominant in species variety. From the flat distribution, the species variety and density of Cyanophyta are higher in west and southwest. The peak of cell density reaches 23.40 x 10(7) cells x L(-1) in September due to the occurrence of cyanobacterial bloom, Cyanophyta account for 90.3 percents, with significant differences in each point (ANOVA, P < 0.05). An obvious succession of phytoplankton species is found, Microcystis of Cyanophyta become the dominant taxa and then conglutinated together to form water bloom. Temperature and pH are the main factors that affect the cyanobacterial bloom, and wind direction is an important reason for the horizontal distribution of the bloom-forming Microcystis. The phytoplankton diversity index is poor in central and western sites, diversity index decreases during cyanobacterial bloom and the community structures are simple.

Objective: To establish an early warning model to simulate the outbreak of influenza based on weather conditions and Yunqi theory, an ancient calendar theory of Chinese medicine (CM)., Methods: Tianjin, a northeastern city in China, was chosen as the region of research and applied the influenza-like illness attack rate (ILI)% as the baseline and warning line to determine the severity of influenza epidemic. Then, an influenza early warning model was constructed based on the theory of rough set and support vector machines (RS-SVM), and the relationship between influenza and meteorology was explored through analyzing the monitoring data., Results: The predictive performance of the model was good, which had achieved 81.8% accuracy when grouping the obtained data into three levels that represent no danger, danger of a light epidemic, and danger of a severe epidemic. The test results showed that if the host qi and guest qi were not balanced, this kind of situation was more likely to cause influenza outbreaks., Conclusions: The outbreak of influenza closely relates to temperature, humidity, visibility, and wind speed and is consistent with some part of CM doctrine. The result also indicates that there is some reasonable evidence in the Yunqi theory.

To understand the relationship between the spatial-temporal variations of phytoplankton primary productivity and its environmental factors in Dianshan Lake, monthly survey was carried out from April, 2009 to March, 2010, with the method of white and black bottles. The result shows that seasonal variation of primary productivity (calculated according to carbon, following the same) is summer [0.95 g x (m3 x d)(-1)] > winter [0.83 g x (m3 x d)(-1)] > spring [0.77 g x (m3 x d)(-1)] > autumn [0.62 g x (m3 x d)(-1). From the flat distribution, primary productivity is higher in northern and southern parts than that in east and west, with no significant differences in each point (p > 0.05). From the vertical distribution, phytoplankton light availability is an important limiting factor. Primary production of 0. 3 m underwater is higher than that of 0.5 m. However, primary production of 0.3 m level in summer is lower because of light inhibition. Seasonal changes in primary productivity may be due to phytoplankton community structure and replacement of the dominant species. There are significantly positive correlation between Chlorophyll a (Chl-a) and phytoplankton density with primary productivity (p < 0.01), and Chl-a has better correlation with primary productivity. Phytoplankton biomass shows a positive reaction to its productivity and may preliminary provide a reference for the number of phytoplankton.