An excellent colorimetric and "turn off" fluorescent probe for tetrahydrofuran based on a luminescent macrocyclic samarium(iii) complex.

In this paper we report a novel probe based on a luminescent 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(iii) complex Sm-2e, originating from the dialdehyde H2Qe and 1,2-bis(2-aminoethoxy)ethane precursors, which is synthesized by the Sm(iii) ion template method. X-ray structural analyses confirm that each ten-coordinate Sm(iii) center with the coordination geometry of a distorted bicapped square antiprism is fully encapsulated by a flexible macrocyclic ligand H2L2e to form a "lasso-type" architecture, and this architecture could enable efficient energy transfer in various solvents confirmed by long lifetimes (33.5-65.2 µs) and high quantum yields (0.23-0.76%) of the Sm(iii) ion. Simultaneously, complex Sm-2e could serve as a probe for sensing organic solvents. Particularly, this complex probe Sm-2e exhibits a highly selective, rapid and sensitive response to tetrahydrofuran (THF), which is easily distinguished by a large absorption shift, even visible to the naked eye, and complete fluorescence quenching. Moreover, the limit of detection for THF is about 0.20% determined by titration experiments, and good selectivity for THF could still be realized in mixture solvents. Consequently, this colorimetric and "turn off" fluorescent probe Sm-2e could be a valuable candidate as a sensor material for sensing THF which has been rarely reported.

Effects of loneliness and isolation on cardiovascular diseases: a two sample Mendelian Randomization Study.

BACKGROUND: Loneliness and isolation are associated with multiple cardiovascular diseases (CVDs), but there is a lack of research on whether they were causally linked. We conducted a Mendelian Randomization (MR) study to explore causal relationships between loneliness and isolation and multiple CVDs. METHODS: Single nucleotide polymorphisms associated with loneliness and isolation were identified from a genome-wide association study (GWAS) of 455,364 individuals of European ancestry in the IEU GWAS database. Summary data for 15 CVDs were also obtained from the IEU GWAS database. We used three MR methods including inverse variance weighting, MR-Egger, and weighted median estimation to assess the causal effect of exposure on outcomes. Cochran's Q test and MR-Egger intercept test were used to evaluate the heterogeneity and pleiotropy. RESULTS: MR analysis showed that loneliness and isolation were significantly associated with essential hypertension (OR = 1.07, 95% CI: 1.03-1.12), atherosclerotic heart disease (OR = 1.04; 95% CI: 1.02-1.06), myocardial infarction (OR = 1.02; 95% CI: 1-1.04) and angina (OR = 1.04; 95% CI =1.02-1.06). No heterogeneity and pleiotropy effects were found in this study. CONCLUSIONS: Causal relationship of loneliness and isolation with CVDs were found in this study.

Gas6 Promotes Microglia Efferocytosis and Suppresses Inflammation Through Activating Axl/Rac1 Signaling in Subarachnoid Hemorrhage Mice.

Early brain injury (EBI) following subarachnoid hemorrhage (SAH) is characterized by rapid development of neuron apoptosis and dysregulated inflammatory response. Microglia efferocytosis plays a critical role in the clearance of apoptotic cells, attenuation of inflammation, and minimizing brain injury in various pathological conditions. Here, using a mouse SAH model, we aim to investigate whether microglia efferocytosis is involved in post-SAH inflammation and to determine the underlying signaling pathway. We hypothesized that TAM receptors and their ligands regulate this process. To prove our hypothesis, the expression and cellular location of TAM (Tyro3, Axl, and Mertk) receptors and their ligands growth arrest-specific 6 (Gas6) and Protein S (ProS1) were examined by PCR, western blots, and fluorescence immunostaining. Thirty minutes after SAH, mice received an intraventricular injection of recombinant Gas6 (rGas6) or recombinant ProS1 (rPros1) and underwent evaluations of inflammatory mediator expression, neurological deficits, and blood-brain barrier integrity at 24 h. Microglia efferocytosis of apoptotic neurons was analyzed in vivo and in vitro. The potential mechanism was determined by inhibiting or knocking down TAM receptors and Rac1 by specific inhibitors or siRNA. SAH induced upregulation of Axl and its ligand Gas6. The administration of rGas6 but not rPros1 promoted microglia efferocytosis, alleviated inflammation, and ameliorated SAH-induced BBB breakdown and neurological deficits. The beneficial effects of rGas6 were arrogated by inhibiting or knocking down Axl and Rac1. We concluded that rGas6 attenuated the development of early brain injury in mice after SAH by facilitating microglia efferocytosis and preventing inflammatory response, which is partly dependent on activation of Axl and Rac1.

Imine bond transformation of a dynamic Sm(III) macrocycle-based chemosensor: The indirect approach for detecting cyanuric chloride.

Herein, we report our strategy to develop the efficient chemosensor and real-time monitoring technique for cyanuric chloride (TCT) detection. A luminescent macrocyclic mononuclear Sm(III) complex Sm-2k bearing with two dynamic imine bonds has been constructed via the template synthesis between dialdehyde H2Qk and matched diamine 1,2-bis(2-aminoethoxy)ethane. Sensing experiments reveal that complex Sm-2k exhibits the turn-off fluorescent and colorimetric response for TCT in CH3OH. It is especially encouraging that this optical sensing process is not only rapid within 60 s but also high-efficient in the presence of TCT analogues as well as sensitive with the low limit of detection (LOD, 1.74 µM) and wide linear sensing range. Mechanism studies demonstrate that TCT sensing is mainly based on the imine bond transformation of probe Sm-2k, which is due to the increased acidity induced by TCT. Meanwhile, a smartphone-based analytical method was developed to make complex Sm-2k accessible for the real-time TCT detection by RGB value outputs. It is believed that this work can shed some constructive lights on design of chemosensors and convenient detection technique for highly reactive analytes.

[Fine root biomass, production, and turnover rate in a temperate deciduous broadleaved forest in the Maoer Mountain, China]. / å¸½å„¿å±±æ¸©å¸¦è½å¶é˜”å¶æž—ç»†æ ¹ç”Ÿç‰©é‡ã€ç”Ÿäº§åŠ›å’Œå‘¨è½¬çŽ‡.

Fine roots play an important role in energy flow and substance cycling in forests. How-ever, the estimates of biomass, production and turnover of fine roots remain large uncertainties, and the mechanism underlying local-scale spatial variation in fine roots is still unclear. In a temperate secondary forest in the Maoer Mountain in Northeast China, we investigated the vertical distribution of fine root biomass and necromass at the 0-100 cm profile and the dynamics, production and turnover rate of fine root in 0-20 cm soil layer. The sequential coring (including the Decision Matrix and the Maximum-Minimum formula) and the ingrowth core (3 cm diameter and 5 cm diameter) were compared in estimating production and turnover rate of fine roots. Forest stand variables that might affect fine roots were also explored. The results showed that 76.8% of fine root biomass and 62.9% of necromass concentrated in the 0-20 cm soil layer, and that both decreased exponentially with increa-sing soil depth. The seasonal variation in both fine root biomass and necromass was not significant in 0-20 cm soil layer, which might be related to the negligible snowfall in winter and the extremely high precipitation in summer. There was no significant difference in the results of the estimated fine root production between two diameter ingrowth cores. After log-transformed, fine root production and turnover rate estimated by the Decision Matrix, the Maximum-Minimum formula and ingrowth cores were significantly different among methods. With the increases of soil nutrient concentrations, fine root biomass/fine root necromass ratio significantly increased, fine root necromass significantly decreased, whereas fine root biomass, productivity, and turnover rate were not related to soil nutrient. There was a significant positive correlation between fine root production and aboveground woody biomass increment in the previous-year but not current-year.

The Long Non-coding RNA LINC01705 Regulates the Development of Breast Cancer by Sponging miR-186-5p to Mediate TPR Expression as a Competitive Endogenous RNA.

Long non-coding RNAs (lncRNAs) may be a regulatory factor of tumorigenesis. However, it is unclear what its biomechanisms are in breast cancer. In this study, different lncRNAs were detected in breast cancer through microarray analysis (GSE119233) and LINC01705 was selected for further study. qRT-PCR was then utilized for the detection of LINC01705 expression in breast cancer cells. A transwell assay, flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU), a cell counting Kit-8 (CCK-8), and a wound-healing assay were performed to determine cell migration, invasion, apoptosis, and proliferation in breast cancer, respectively. For the identification of potential targets of LINC01705, dual-luciferase reporter gene and bioinformatics assays were conducted. Moreover, for the clarification of their interaction and roles in the regulation of the occurrence of breast cancer, Western blotting and RIP assays were conducted. Our findings revealed high LINC01705 expression in breast cancer tissues relative to adjacent non-cancerous tissues (n = 40, P < 0.001). Overexpression of LINC01705 notably enhanced cell migration and proliferation in breast cancer. In addition, LINC01705 positively regulated the translocated promoter region, nuclear basket protein (TPR) through competition with miR-186-5p. In conclusion, our results suggest that LINC01705 is implicated in the progression of breast cancer via competitively binding to miR-186-5p as a competing endogenous RNA (ceRNA), thereby regulating TPR expression.

Heart failure and left ventricular dysfunction in older patients with chronic kidney disease: the China Hypertension Survey (2012-2015).

BACKGROUND: Heart failure (HF) is a leading cause of hospitalization and mortality for older chronic kidney disease (CKD) patients. However, the epidemiological data is scarce. We aimed to determine the prevalence of left ventricular (LV) dysfunction and HF, and to explore the risk factors for HF among those patients. METHODS: This is a cross-sectional analysis of the China Hypertension Survey conducted between October 2012 and December 2015. A total of 5, 808 participants aged ≥ 65 years were included in the analysis. Self-reported history of HF and any other cardiovascular diseases was acquired. 2-D and Doppler echocardiography were used to assess LV dysfunction. CKD was defined as either estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m2 or urinary albumin to creatinine ratio (ACR) ≥ 30 mg/g. RESULTS: Among CKD patients aged ≥ 65 years, the weighted prevalence of HF, heart failure with preserved ejection fraction (HFpEF), heart failure with mid-range ejection fraction (HFmrEF), and heart failure with reduced ejection fraction (HFrEF) was 4.8%, 2.5%, 0.8%, and 1.7%, respectively. The weighted prevalence of HF was 5.0% in patients with eGFR < 60 mL/min per 1.73 m2, and was 5.9% in patients with ACR ≥ 30 mg/g. The prevalence of LV systolic dysfunction was 3.1%, and while it was 8.9% for moderate/severe diastolic dysfunction. Multivariate analysis showed that smoking was significantly associated with the risk of HF. Furthermore, age, smoking, and residents in rural areas were significantly associated with a risk of LV diastolic dysfunction. CONCLUSIONS: The prevalence of HF and LV dysfunction was high in older patients with CKD, suggesting that particular strategies will be required.

Series of Highly Luminescent Macrocyclic Sm(III) Complexes: Functional Group Modifications Together with Luminescence Performances in Solid-State, Solution, and Doped Poly(methylmethacrylate) Film.

Here, we report our trials to regulate the luminescence performance of the macrocyclic samarium(III) complex and prepare four excellent luminescent Sm(III) complex-doped poly(methylmethacrylate) (PMMA) composites. Four 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(III) complexes, Sm-2 a -Sm-2 d , originating from dialdehydes with different pendant arms and 1,2-bis(2-aminoethoxy)ethane, have been constructed by the template method. Crystal structures reveal that every Sm(III) ion with the coordination geometry of a distorted bicapped square antiprism is capsulated by the macrocyclic cavity environment forming the "lasso-type" protection. Relative photophysical properties of macrocyclic Sm(III) complexes are carefully investigated in solid-state, methanol solution, and doped PMMA film, and all these show characteristic emissions of the Sm(III) ion associated with satisfactory lifetimes and quantum yields in all media, which could be comparable to reported outstanding examples. Especially, the luminescence performance for this type of Sm(III) complex could be regulated in the solid state by the use of different functional groups in the pendant arm while it is not achieved in solution and the doped PMMA composite. High emitting and air-stable plastic materials could be obtained when these Sm(III) complexes are doped in PMMA with 0.1 wt % mixing ratio, and the corresponding maximum lifetime and quantum yield are 61.2 µs and 0.63% in the case of complex Sm-2 a , respectively. We believe that these highly luminescent "lasso-type" Sm(III) complexes and doped PMMA composites are valuable references in the design of luminescent lanthanide(III) hybrid materials.

[Validation and generalizability of the predictive model of ischemic cardiovascular diseases in Chinese].

OBJECTIVE: To evaluate the applicability of developed prediction models of ischemic cardiovascular diseases (ICVD) in Chinese to other Chinese populations. METHOD: We used the independent prospective cohort established in early 1990's from China Multi-Center Collaborative Study of Cardiovascular Epidemiology (MUCA), as the validation cohort, to test the hypothesis. The area under ROC curve (AUC) based on the application of the Cox optimal model and the simplified model to the validation cohort were calculated and to test the ability of the prediction models to discriminate events from nonevents. Applicability was evaluated by comparing the mean probability estimates in each decile of probability in the validation cohort with the observed incidence with the Hosmer-Lemeshow test. RESULTS: The validation cohort enrolled a total of 17 329 men and women aged 35 to 59 years baseline 1992 - 1994. In this paper, we used data from the remaining 15 100 participants after excluding 2229 subjects for at missing value of risk factors. During 11-year follow up of the cohort, there were 347 ICVD events (206 for men and 141 for women), including 83 coronary heart disease events (56 men and 27 women) and 268 ischemic strokes (154 men and 114 women). ROC curves for men and women showed good and almost identical discrimination for optimal model (the AUCs (95% CI) were 0.796 (0.762 - 0.829) for men and 0.791 (0.755 - 0.828) for women), simplified model (the AUCs (95% CI) were 0.792 (0.758 - 0.825) for men and 0.783 (0.746 - 0.821) for women) and score system (the AUCs (95% CI) were 0.791 (0.757 - 0.825) for men and 0.779 (0.741 - 0.817) for women) in the validation cohort. The predicted 10-year risk of ICVD by optimal models and observed incidence of ICVD in the validation cohort in each decile were compared. Hosmer-Lemeshow chi2 was 3.7 for men (P = 0.879) and 27.7 for women (P < 0.001). Whereas the largest difference between the observed rate and the predicted rate was only 1%. CONCLUSIONS: The prediction models for estimating 10-year risk of ICVD had satisfied predictive capability when they were applied to the validation cohort and are applicable to other Chinese populations.

Protective effects of traditional Tibetan medicine Zuo-Mu-A Decoction () on the blood parameters and myocardium of high altitude polycythemia model rats.

OBJECTIVE: To explore the protective effects of Tibetan medicine Zuo-Mu-A Decoction (, ZMAD) on the blood parameters and myocardium of high altitude polycythemia (HAPC) model rats. METHODS: Forty male Wistar rats were randomly divided into 4 groups by a random number table, including the normal, model, Rhodiola rosea L. (RRL) and ZMAD groups (10 in each group). Every group was raised in Lhasa to create a HAPC model except the normal group. After modeling, rats in the RRL and the ZMAD groups were administered intragastrically with RRL (20 mL/kg) and ZMAD (7.5 mL/kg) once a day for 2 months, respectively; for the normal and the model groups, 5 mL of distilled water was administered intragastrically instead of decoction. Then routine blood and hematologic rheology parameters were taken, levels of erythropoietin and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were tested, and ultrastructural change in the left ventricular myocardium was observed using transmission electron microscopy. RESULTS: Compared with the model group, ZMAD significantly reduced the red blood cell count, hemoglobin levels, whole blood viscosity at low/middle shear rates, plasma viscosity, erythrocyte electrophoretic time, erythropoietin and 8-OHdG levels, and also increased the erythrocyte deformation index (P<0.05). There was no difference in all results between the RRL and the ZMAD groups. The cardiac muscle fibers were well-protected, mitochondrial matrix swelled mildly and ultrastructure changes were less prominent in the ZMAD group compared with the model group. CONCLUSION: ZMAD has significant protective effects on the blood parameters against HAPC, and also has the beneficial effect in protecting against myocardial injury.

[A cohort study on parental history of hypertension and the risk of cardiovascular disease in Chinese population].

OBJECTIVE: To assess the relationship between parental history of hypertension and the incidence of cardiovascular disease in Chinese populations. METHODS: A total of 15 131 individuals (7015 men and 8116 women, aged from 35 to 59 years) in China were enrolled and followed up from 1992 to 2005. The information on the parental history of hypertension of the participants was collected. The individuals were divided into three groups according to their parental history of hypertension: those without parental history of hypertension (group 1), those with one parent history of hypertension (group 2) and those with both parents history of hypertension (group 3). The hazard ratio and its 95% confidence interval were calculated using the Cox proportional hazard model. RESULTS: There were 448 cardiovascular events (including 82 cardiac events and 370 stroke events and 4 with both cardiac and stroke events) during the 163 858 person-years of observation. After adjusting for age, smoking and drinking, the hazard ratio for cardiovascular disease for group 1, group 2 and group 3 were 1.00, 1.34 (1.01 - 1.78), 2.58 (1.62 - 4.11) in men respectively and 1.00, 1.77 (1.27 - 2.45), 2.55 (1.44 - 4.54) in women respectively. After further adjusting for serum total cholesterol (TC), high density lipid cholesterol (HDL-C), fasting glucose, body mass index (BMI) and systolic blood pressure (SBP) in the model, the hazard ratio for cardiovascular disease for those three groups were 1.00, 1.01 (0.76 - 1.35), 1.72 (1.07 - 2.75) in men respectively and 1.00, 1.31 (0.94 - 1.84), 1.76 (0.98 - 3.15) in women respectively. CONCLUSION: The individuals with parental history of hypertension have a higher risk of cardiovascular disease, especially for those with both parents history of hypertension.

[The cut-off point of waist circumference for identifying metabolic syndrome in Chinese adults].

OBJECTIVE: Metabolic syndrome has attracted more attention from scientists of related areas due to its association with increased risk of cardiovascular disease and diabetes. The clinical identification criteria for metabolic syndrome issued by ATP III of NECP indicate the enlarged waist as the first component using the cut-offs derived from Caucasians. The purpose of this study is to investigate the appropriate cut-offs of waist circumference for Chinese adults as a component of metabolic syndrome. METHODS: Database of 13732 Chinese adults with 35 - 59 years from the risk factor survey in 1998 (the 9(th) Five Year National Project on trends and prediction of cardiovascular disease) was used to analyze the ORs of clustering of risk components by different strata of waist circumference. The sensitivity, specificity and distance in ROC curve by different cut-offs of waist circumference for identifying two or more risk components of metabolic syndrome were estimated to find the cut-off point for men and women with the shortest distance in ROC curve. RESULTS: The ORs of clustering of risk components increased significantly with the size of waist circumference. The waist circumference (>/= 85 cm for men, >/= 80 cm for women) corresponded to the shortest distance in ROC curve, namely, at these cut-offs, the rates of false positive and false negative for identifying clustering of two or more risk components were the minimum. CONCLUSIONS: If a person had three or more of the following components, metabolic syndrome could be defined: waist circumference >/= 85 cm in men or >/= 80 cm in women, SBP >/= 130 mm Hg or DBP >/= 85 mm Hg, TG >/= 1.69 mmol/L, HDL-C < 1.03 mmol/L and fasting blood glucose >/= 6.1 mmol/L. The prevalence of metabolic syndrome was 19.3% and 13.9% in middle-aged men and women respectively. In these patients the combination of enlarged waist, high blood pressure and high TG was the most frequent. This recommendation need further confirmed in representative sample of Chinese population.

[A cohort study on the relationship between nutrients intake and the incidence of hypertension in middle-aged Chinese].

OBJECTIVE: To explore the relationship between nutrient intake and the incidence of hypertension in middle-aged Chinese. METHODS: A prospective study was conducted in 653 men and women of Beijing and Guanzhou, aged 35-59 years. The subjects had no hypertension or other cardiovascular diseases at baseline risk factor and dietary survey carried out in 1983-1984. The baseline information of nutrient intake was collected by using a 24-hour recall method on three consecutive days. The incidence of hypertension was determined through the follow-up survey in 1993-1994. The subjects were categorized into three groups according to tritiles of each baseline nutrient intake and the relative risk for hypertension incidence in each group was calculated by using the logistic regression model with the group of lowest risk as the referent. RESULTS: During the period of 1983-1984 to 1993-1994, 170 among 653 subjects had developed hypertension; 92 were men and 78 were women. After adjustment for other risk factors, the relative risk of hypertension for different protein intake groups was 1.0, 0.87 (95% CI 0.54-1.40) and 0.52 (95% CI 0.32-0.87), respectively, and the p value for trend analysis was 0.011; the relative risk of hypertension for different sodium intake groups was 1.0, 1.12 (95% CI 0.66-1.88) and 1.85 (95% CI 1.09-3.14), respectively, and the p value for trend analysis was 0.015. There was no significant relationship between the other nutrient intake and hypertension incidence. CONCLUSION: Among middle-aged Chinese, protein and sodium may be two of the most important dietary factors affecting the incidence of hypertension. Increasing protein intake and reducing sodium intake might be helpful for the prevention of hypertension.

Proportion of different subtypes of stroke in China.

BACKGROUND AND PURPOSE: The goal of this article is to clarify the proportion of stroke subtypes in China, where stoke is the most common cause of death. METHODS: A total of 16,031 first-ever strokes in subjects >or=25 years of age were identified in 1991 to 2000 from 17 Chinese populations through a community-based cardiovascular disease surveillance program in the China Multicenter Collaborative Study of Cardiovascular Epidemiology. World Health Organization diagnosis criteria were used for classification of stroke subtypes. RESULTS: CT scan rate of stroke cases reached a satisfactorily high level only after 1996 in the study populations. In 8268 first-ever stroke events from 10 populations with CT scan rate >75% in 1996 to 2000, 1.8% were subarachnoid hemorrhage, 27.5% were intracerebral hemorrhage, 62.4% were cerebral infarction, and 8.3% were undetermined stroke. The proportion of intracerebral hemorrhage varied from 17.1% to 39.4% and that for cerebral infarction varied from 45.5% to 75.9% from population to population. The ratio of ischemic to hemorrhagic stroke ranged from 1.1 to 3.9 and averaged 2.0). The 28-day fatality rate was 33.3% for subarachnoid hemorrhage, 49.4% for intracerebral hemorrhage, 16.9% for cerebral infarction, and 64.6% for undetermined stroke. CONCLUSIONS: In our study, ischemic stroke was more frequent and its proportion was higher than hemorrhagic stroke in Chinese populations. Although hemorrhagic stroke was more frequent in Chinese than in Western populations, the variation in the proportion of stroke subtypes among Chinese populations could be as large as or larger than that between Chinese and Western populations.

[The incidence of ischemic and hemorrhagic stroke in Chinese populations].

OBJECTIVE: To study the ratio of ischemic to hemorrhagic stroke incidence in Chinese populations. METHODS: Fifteen populations in China, each including about 100,000 residents, were monitored from 1991 to 2000 for the occurrence of stroke. Stroke was classified as hemorrhagic, ischemic and unclassified based on the clinical data and CT scan results respectively. RESULTS: The average CT scan rate in stroke patients from 1996 to 2000 varied from 14.8% to 97.5% among the 15 population and the average ratio of ischemic to hemorrhagic stroke ranged from 0.23:1 to 4.38:1; the correlation coefficient between the ratio and CT scan rate is 0.7 (P = 0.003). In all the populations with CT scan rate greater than 80%, the ischemic to haemorrhagic ratios were all greater than 1.0. From 1991 to 2000 in 12 populations with complete data, the CT scan rate in stroke patients rose from 41.1% to 88.3% and the ischemic to hemorrhagic ratio rose from 1.25:1 to 1.85:1. The correlation coefficient between the ratio and the CT scan rate was 0.9 (P < 0.001). In patients having CT scan, the ischemic to hemorrhagic ratio was greater than 1.0 in all the years. CONCLUSION: The predominant type of stroke in Chinese population is ischemic. The low CT scan rate in some populations is the main reason for the false impression predominantly hemorrhagic stroke.

Homology modelling and site-directed mutagenesis studies of the epoxide hydrolase from Phanerochaete chrysosporium.

Three-dimensional structural model of epoxide hydrolase (PchEHA) from Phanerochaete chrysosporium was constructed based on X-ray structure of Agrobacterium radiobacter AD1 sEH using SWISS-MODEL server. Conserved residues constituting the active site cavity were identified, of which the functional roles of 14 residues were determined by site-directed mutagenesis. In catalytic triad, Asp105 and His308 play a leading role in alkylation and hydrolysis steps, respectively. Distance between Asp105 and epoxide ring of substrate may determine the regiospecificity in the substrate docking model. Asp277 located at the entrance of substrate tunnel is concerned with catalysis but not essential. D307E had the highest activity and lower enantioselectivity among 14 mutants, suggesting Asp307 may be involved in choice of substrate configuration. Y159F and Y241F almost exhibited no activity, indicating that they are essential to bind substrate and facilitate opening of epoxide ring. Besides, His35-Gly36-Asn37-Pro38, Trp106 and Trp309 surrounding Asp105, may coordinate the integration of active site cavity and influence substrate binding. Especially, W106I reversed the enantioselectivity, perhaps due to more deteriorative impact on the preferred (R)-styrene oxide. Gly65 and Gly67 occurring at ß-turns and Gly36 are vital in holding protein conformation. Conclusively, single conserved residue around the active sites has an important impact on catalytic properties.

Characterization of a unique proline iminopeptidase from white-rot basidiomycetes Phanerochaete chrysosporium.

A putative gene encoding proline iminopeptidase (PchPiPA) was cloned from Phanerochaete chrysosporium BKM-F-1767 by RT-PCR and expressed successfully in Escherichia coli. The cDNA is 942 bp in length and encodes 313 amino acids. The recombinant enzyme was only able to hydrolyze Pro-pNA among the tested synthetic substrates. There is no activity detected toward Leu-pNA, Phe-pNA and Tyr-pNA, as well as GGG-pNA, SGR-pNA, AAV-pNA, AAPL-pNA, AAVA-pNA. And the recombinant enzyme could cleave the peptides derived from enzyme-hydrolytic natural proteins to release free lysine, which was confirmed using synthetic oligopeptides with lysine at N termini as substrate. The optimal pH and temperature for this enzyme were 8.0 and 45 degrees C, respectively. The catalytic activity was inhibited slightly by Mg(2+), Al(3+), Ca(2+), Fe(3+), Fe(2+) and Ba(2+); strongly by Ni(2+), Mn(2+) and Co(2+), and almost inactivated by Zn(2+), Cu(2+) and Hg(2+). In addition, the enzyme was not sensitive to EDTA-Na(2), as well as redoxes of DTT, beta-ME and H(2)O(2). The protease inhibitors of benzamidine hydrochloride and phenylmethyl sulfonyfluoride caused a moderate inhibition. The V(max), K(m) and k(cat) toward Pro-pNA were 347.86 mumol min(-1) mg(-1), 2.15 mM and 218.10 S(-1), respectively. The deduced catalytic triad of Ser(107), Asp(264) and His(292) was confirmed by site-directed mutagenesis because the individual replacement of Ser(107) to Asp, Asp(264) to Ala or His(292) to Leu led complete inactivation. Transcriptional analysis by RT-PCR showed that PchPiPA could be expressed under ligninolytic and non-ligninolytic conditions. Conclusively, it was suggested that the proline iminopeptidase may be a member of the proteolytic system in this fungus. The availability of recombinant protein may be potentially used in certain proteolytic processing.

[Hypertension Control in Communities (HCC): evaluation result of blood pressure management among hypertensive].

OBJECTIVE: To determine the effects related to community-based standardized blood pressure management programs on the control of hypertension. METHODS: A protocol of community-based standardized blood pressure management was developed based on the current Chinese guideline for prevention, treatment of hypertension. Grass-roots caretakers from community health service centers across China were trained using this protocol and required to manage hypertensive patients according to the protocol. Patients were treated on therapeutic life style change or/and medication, and followed up based on the criteria of risk stratification. The control rate of hypertension was evaluated after 1 year. Effect of intervention (EI) was estimated as '1 year rate (mean)' minus the number showed at the baseline. RESULTS: By the end of 2008, a total of 29 411 hypertensive patients (47.2% for male, mean age 61.4 +/- 10.9 years) with full information had been under management for one year according to the protocol. Among all patients, 8.9% were classified as under low risk, 50.8% as moderate risk and 40.3% as high and very high risk showed in baseline data. After standardized management, the EI of smoking, drinking and systolic/diastolic blood pressure were -7.1% (P < 0.05), -7.3% (P < 0.05), and -14.8-8.3 mm Hg (P < 0.05), respectively. However, EI of overweight/obesity was 0.3% (P > 0.05). For all patients, the control rate rose to 74.7%, with EI as 53.1%, and all of the sub-groups, including age, risk stratification, had significant increases. The longer the management was under, the higher the control rate was seen. Results from the multivariate logistic regression showed that older age, male and having higher blood level were adverse factors for the undertaking the control and management programs of hypertension. CONCLUSION: Results from our study showed that standardized management could significantly improve the program on the control of hypertension at the community level, in China.

[A cohort study on parental history and risk factors of stroke in Chinese population].

OBJECTIVE: To assess the relationship between parental history and the incidence of stroke in Chinese populations. METHODS: A total of 15,131 individuals (7015 men and 8116 women, aged from 35 to 59 years) in China were enrolled and followed up from 1992 to 2005. Information on the parental history of stroke of the participants was collected at baseline study under face to face interview. Individuals were divided into three groups according to their parental history of hypertension: those with no parental history of hypertension (Group 1), those with only one parent having the history of hypertension (Group 2) and those with both parents having the history of hypertension (Group 3). The hazard ratio and its 95% confidence interval were calculated using the Cox proportional hazard model. RESULTS: There were 370 stroke events during 163 858 person-years of observation. After adjusting for age and sex, the hazard ratioon stroke for group 1, group 2 and group 3 were 1.00, 1.74 (1.33-2.29), 3.61 (1.86-7.01), respectively. After adjusting for age, sex, smoking, drinking, serum total cholesterol (TC), high density lipid cholesterol (HDL-C), fasting glucose, body mass index (BMI) and systolic blood pressure (SBP) in the model, the hazard ratio for stroke of those three groups were 1.00, 1.34 (1.02-1.77), 2.50 (1.29-4.87), respectively. CONCLUSION: Individuals with parental history of stroke had a higher risk of stroke, and this was especially true for those with both parents having the history of stroke.