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Carbon dots (CDs) with average diameter of 3.1 ± 0.5 nm were facilely synthesized with candle soot through hydrothermal reaction in sodium hydroxide aqueous solution. The as-prepared CDs were covered with a lot of hydroxyls, possessed properties of good water-solubility, anti-photobleaching, salt tolerance, and low cytotoxicity, and had a fluorescence quantum yield (QY) of about 5.5%. The fluorescence of the hydroxyls-coated CDs could be selectively quenched by metal ions such as Cr3+, Al3+ and Fe3+, which is because these metals can easily combine with the hydroxyl groups on the surface of CDs and induce aggregation of hydroxyls-coated CDs. Experiments showed that the quenching of Cr3+ had a Sterm-Volmer constant of 1.03 × 107 M-1 with a liner range of 1.0-25.0 μM and detection limit of 60 nM (3σ).

Gold nanoparticles (AuNPs) have the unique property of plasmon resonance absorption (PRA). In this contribution, universal colorimetric detection of oxidants was achieved using cysteine induced AuNPs aggregation, which leads to a red-shift of in the PRA. The SH group of a cysteine molecule can be oxidized into a –S–S– bond in the presence of oxidants such as H2O2 or 1O2, which leads to reduced aggregation in the AuNPs. These blue-shifts of the PRA from 740 nm to 531 nm, and results in a blue-to-red color change. It was found that the ratio of absorbance at 740 nm to that at 531 nm ( A 740/ A 531) was in proportion to the concentrations of H2O2 and 1O2. Also, this colorimetric method can be successfully applied to detecting H2O2 in rat brains, which offers performance similar to flow injection-chemiluminescence.

Background In developed countries, hospitalized patients with acute medical conditions are at significant risk for venous thromboembolism (VTE). Little is known about VTE risk and prophylaxis practices in China. Objective To determine the VTE risk and the frequency of recommended VTE prophylaxis in hospitalized Chinese patients with acute medical conditions. Methods Multi-center, cross-sectional, observational study. Eligibility criteria: ≥ 30 years, admitted to an intensive care unit (ICU)/coronary care unit (CCU) for acute medical illness, had ≥ 1 VTE risk factor/1 disease that predisposes to VTE, and provided informed consent. We used 2004 American College of Chest Physicians (ACCP) evidence-based consensus guidelines to assess VTE risk and the frequency of recommended VTE prophylaxis. Results 1247 patients from 19 hospitals in 11 cities across 11 provinces of China were enrolled from July 2007 to June 2008. 57.3% patients had > 2 VTE risk factors. Only 20.2% received ACCP-recommended VTE prophylaxis (CCU patients: 22.7%, ICU patients: 16.9%, p = 0.0117). Limitations Excluding some patients with VTE risk factors did not allow assessment of the prevalence of VTE risk in the acute hospital-care setting. We could not determine whether the duration of prophylaxis complied with the ACCP recommendations. Our results may not be representative of hospitals in small cities/rural areas in China. Conclusions The prevalence of VTE risk factors in Chinese patients was similar to that in developed countries; however, only a small proportion of eligible patients received the recommended VTE prophylaxis. Our findings highlight the need for dissemination and implementation of appropriate VTE prophylaxis guidelines in China.

Biotransformation of L-phenylalanine (L-Phe) to 2-phenylethanol (2-PE) was limited by product cytotoxicity. In order to improve 2-PE production, a biotransformation strategy applying in situ product adsorption was investigated. Resin HZ818 was chosen from several macroporous adsorbent resins, which adsorbed the most 2-PE and the least L-Phe. When 7% (dry w/v) resin HZ818 was added to the biotransformation system, 6.6 g l−1 2-PE was obtained from 12 g l−1 L-Phe, with a molar yield of 74.4%. Compared to the biotransformation without addition of adsorbent resin, the product concentration was improved by 66.2%. Adsorption of the produced 2-PE onto the resin facilitated product recovery and made the process more feasible for industrial application.

This paper attempts an investigation of the impact of the China factor on the global commodity and ocean shipping freight volatilities in recent years. It measures China's contribution to the incremental growth in demand for selected bulk commodities and ocean shipping in the world. China's impact on price volatilities is statistically analyzed through a conventional econometric framework.

Precision medicine is a new medical concept and medical model, which is based on personalized medicine, rapid progress of genome sequencing technology and cross application of biological information and big data science. Precision medicine improves the diagnosis and treatment of gastric cancer to provide more convenience through more profound analyses of characteristics, pathogenesis and other core issues in gastric cancer. Cancer clinical database is important to promote the development of precision medicine. Therefore, it is necessary to pay close attention to the construction and management of the database. The clinical database of Sun Yat-sen University Cancer Center is composed of medical record database, blood specimen bank, tissue bank and medical imaging database. In order to ensure the good quality of the database, the design and management of the database should follow the strict standard operation procedure(SOP) model. Data sharing is an important way to improve medical research in the era of medical big data. The construction and management of clinical database must also be strengthened and innovated.

A 107-cm-long lake core was drilled in South Hongshan Lake (35°10′N, 80°04′E, 5060 m a.s.l.) shows 150 yr of environmental change as inferred from ostracoda assemblages. Four species of ostracoda, which belong to four genera, have been identified. The ostracoda distribution in the core can be divided into six ostracoda assemblages as follows: OA1—Ilyocypris biplicata–Limnocythere inopinata assemblage; OA2—Limnocythere inopinata–Leucocythere mirabilis assemblage; OA3—Leucocythere mirabilis–Limnocythere inopinata assemblage, in which dominant species is Limnocythere inopinata; OA4—Nearly ostracoda free; OA5—Eucypris inflata–Limnocythere inopinata assemblage; and OA6—Limnocythere inopinata changes from dominant to sole species. These ostracoda assemblages, together with other proxies, imply the following environmental sequence for the past 150 yr in the study area. Shallow moving water appears in A.D. 1850–1884, followed by a warm-humid climate in 1884–1922. Lake level decreased and water temperatur...

Circulating tumor cells (CTCs) have been detected by us and others in cancer patient blood. However, little is known about how to specifically capture and deactivate CTCs in vivo, which may lead to successful metastasis prevention in asymptomatic cancer survivors after surgery. We hypothesize that the dual antibody conjugates may have the advantage of capturing CTCs specifically over their single antibody counterparts. Here we show that the surface-functionalized dendrimers can be sequentially coated with two antibodies directed to surface biomarkers (EpCAM and Slex) of human colorectal CTCs. The dual antibody-coated dendrimers exhibit a significantly enhanced specificity in capturing CTCs in the presence of interfering blood cells, and in both eight-patient bloods and nude mice administered with the labeled CTCs in comparison to their single antibody-coated counterparts. The dual antibody-coated conjugates down-regulate the captured CTCs. This study provides the first conceptual evidence that two antibodies can be biocompatibly conjugated to a nanomaterial to capture and down-regulate CTCs in vivo with the enhanced specificity.

Ursolic acid (UA) is a natural product which has been shown to possess a wide range of pharmacological activities, in particular those with anticancer activity. In this study, 13 novel ursolic acid derivatives were designed and synthesized in an attempt to further improve compound potency. The structures of the newly synthesized compounds were confirmed using mass spectrometry, infrared spectroscopy, and (1) H NMR. The ability of the UA derivatives to inhibit cell growth was assayed against both various tumor cell lines and a non-pathogenic cell line, HELF. Analysis of theoretical toxicity risks for all derivatives was performed using OSIRIS and indicated that the majority of compounds would present moderate to low risks. Pharmacological results indicated that the majority of the derivatives were more potent growth inhibitors than UA. In particular, 5b demonstrated IC50 values ranging from 4.09 ± 0.27 to 7.78 ± 0.43 μm against 12 different tumor cell lines. Flow cytometry analysis indicated that 5b induced G0/G1 arrest in three of these cell lines. These results were validated by structural docking studies, which confirmed that UA could bind to cyclins D1 (Cyc D1) and cyclin-dependent kinases (CDK6), the key regulators of G0/G1 transition in cell cycle, while the piperazine moiety of 5b could bind with glucokinase (GK), glucose transporter 1 (GLUT1), and ATPase, which are the main proteins involved in cancer cell metabolism. Acridine orange/ethidium bromide staining confirmed that 5b was capable of inducing apoptosis and decreasing cell viability in a dose-dependent manner.

PRISMA 2009 checklist in current meta-analysis. (DOC 70Â kb)

Newcastle-Ottawa Quality Assessment Scale. (PDF 36Â kb)

The 1.07-m long lake core with 1 cm interval cutting, which was obtained by drilling in the South Hongshan Lake of Northwest Tibet, was dated by the Pb-210 and (CS)-C-137 methods, and a 150-year consecutive lake sedimentary sequence (1840-1997) with 1.4 year resolution was obtained. Some environmental proxies, such as the total organic carbon (TOC), total nitrogen (TN), ratio of TOC to TN (TOC/TN), trace chemistry elements (TCE), CaCO3, grain size, richness of ostracoda etc. showed that they are of well coincidence. These results implied that the environmental background varied from the cold-wet period in the late 19th century, to the warm-wet period from the end of the 19th century to the 1920s and to the warm-dry period since the 1920s. There were sub-variations since the 1920s: the cold-dry/warm-wet fluctuation from 1922 to 1960, the intensively warm-dry period since 1960 with a short cold-wet period in the mid-1970s to the end of the 1980s. The humid period from the mid-1970s to the end of the 1970s and the dry period beginning from the early 1980s were well documented by climatic data of the nearby weather station records while the grain size was well correlated to the annual precipitation. Compared with the records from Guliya ice core in the same area, the TOC proxy in the lake core indicating warm/cold conditions well corresponded to the delta(18)O records representing temperature variations in the ice core. However, the proxies with dry/wet significance in the lake core were different from the variations of snow accumulation reflected by the ice core. It can be concluded that the chosen environmental proxies have clear environmental significance and the lake sediments can reflect climatic and environmental changes at high-resolution.

Metastatic soft tissue sarcomas (STS) represent enormous challenges to improve the low survival rate, which is almost the same as past 2 decades ago, although surgery, radiotherapy and radiofrequency ablation has been accepted in the treatment of metastatic STS. Moreover, STS varies between elderly and younger victims in the aspect of diagnoses, prognosis, and treatment strategies. In order to evaluate the role of local treatment in improving prognosis for patients with metastatic STS and select the proper candidates who will benefit from local therapy, a single-institution nearly 50-year experience were collected and reviewed. Finally, we found that local treatments could improve treatment response and survival, but overall survival advantage could not be seen in elderly patients. This conclusion from a single institution could serve as a basis for future prospective multi-institutional large-scale studies.

A novel and rapid spectrofluorometry method for the recognition of 6-mercaptopurine (6-MP) has been developed based on luminescent metal-organic frameworks Fe-MIL-88NH2 as fluorescent probe. The strong fluorescence of Fe-MIL-88NH2 at 430 nm could be quenched by 6-MP directly, and the Fe-MIL-88NH2 shows high selectivity for 6-MP compared to other thiol-containing amino acids such as homocysteine (Hcy), cysteine (Cys), glutathione (GSH), etc. Under optimal conditions, the relative fluorescence intensity was linearly proportional to the concentration of 6-MP in the range of 5-600 μM with the detection limit at 1.17 μM (S/N=3). Furthermore, the present approach has been successfully applied to the determination of 6-MP in human serum samples. The possible fluorescence quenching mechanism has also been investigated, where it is revealed that the quenching was attributed to competition of absorption of the light source energy as well as electron transfer between Fe-MIL-88NH2 and 6-MP.

Ursolic acid (UA) is a naturally bioactive product that exhibits potential anticancer effects. The relatively safe and effective molecule intrigued us to explore a way to further improve its anti-cancer activity and tumor-targeting specificity. In the present study, a series of structural modifications of UA was achieved, which resulted in significant increase in growth inhibition on various cancer cell lines with minimal effects on normal cells. The leading molecule US597 (UA-4) caused depolarization of mitochondrial membrane potential, cell arrest in G0/G1 phase and apoptosis/necrosis in a dose-dependent manner. Structural docking suggested that the carbon chains of the modified UA derivatives compete strongly with glucose for binding to glucokinase, the key glycolysis enzyme presumably active in cancer cells. The combination of 2-deoxy-D-glucose (2-DG) and UA-4 induced cell cycle arrest in G2/M phase, promoted caspase-dependent cell death, reduced hexokinase activity, aggravated depletion of intracellular ATP, decreased lactate production and synergistically inhibited cancer cell growth in vitro (HepG2) and in vivo (H22). Collectively, our findings suggest that the structural modification enhances efficacy and selectivity of UA, and the combination of UA-4 with 2-DG produces synergistic inhibition on hepatoma cell proliferation by dual targeting of apoptosis and glycolysis.

To investigate changes in clinicopathological features and survival of patients with gastrectomy at a single institution in China.From January 1990 to December 2009, clinicopathological data of 2518 cases of gastric cancer patients who underwent surgical resection in the Sun Yat-sen University Cancer Center were analyzed retrospectively. The overall survival rate was determined using Kaplan-Meier method and log-rank test was used to determine significance. The prognosis was analyzed using univariate analysis and multivariate analysis by Cox proportional hazards model. Clinical features, pathological findings and survival differences were compared in this cohort between two consecutive periods(1990-1999 and 2000-2009).The 5-year survival rates for the whole cohort and those undergoing radical resection was 48.1% and 53.7%, respectively. In the first period, the 5-year survival rate for the whole cohort and for patients undergoing radical resection was 40.1% and 45.7%. In the second period, the 5-year survival rates for whole cohort and for patients undergoing radical resection was 51.5% and 57.1%, respectively. For those who underwent radical resection, the mean number of lymph node dissection was significantly higher in the recent period (20.1±8.3 vs. 9.5±6.0, P0.01). On multivariate analysis by means of the Cox proportional hazard model, age, location, tumor size, histological type, radical resection, lymphatic/venous invasion, depth of invasion, nodal status, number of retrieved lymph nodes, and treatment period were independent factors (P0.05). The constitution, number of retrieved lymph nodes, and survival rate were all improved between the two intervals (P0.05).The overall survival rate has gradually increased in gastric cancer patients over the past 20 years.

The systemic analyses have been carried out in this paper to the paleolake shorelines, paleolake sediments and paleoclimatic proxies of 20 lakes, in which there were 12 kaBP dating data on the Tibetan Plateau. The results showed that the paleolake level had apparently risen during 14-11 kaBP, the glaciers melting period, in the Tibetan area and Northwest China. Especially, much more increasing amplitude supplied by thawy glaciers water occurred than in the best period of Holocene. The temperate-humid climate around 12 kaBP appeared in the Tibetan area and even in the whole China. This event may be compared with the Bolling/Allerod warm period which was reflected by Europe and Greenland ice core records. It showed that the B/A event was not a regional one in the North Atlantic area.

The microarray of DNA probes with 5 -NH2 and 5 -Tex/3 -NH2 modified terminus on 10 μm carboxylate functional beads surface in the presence of 1-ethyl-3-(3-dimethylaminopropyl)- carbodiimide (EDC) is characterized in the present paper. It was found that the microarray capacity of DNA probes on the beads surface depends on the pH of the aqueous solution, the concentration of DNA probe and the total surface area of the beads. On optimal conditions, the minimum distance of 20 mer single-stranded DNA probe microarrayed on beads surface is about 14 nm, while that of 20 mer double-stranded DNA probes is about 27 nm. If the probe length increases from 20 mer to 35 mer, its microarray density decreases correspondingly. Mechanism study shows that the binding mode of DNA probes on the beads surface is nearly parallel to the beads surface.

A 12.4 m core collected from the eastern part of Lake Bangong provided a continuous Holocene record. This core was analyzed for diatoms, ostracods, charophytes, content in total organic carbon and identification of organic particles contained in the sediments. The record is remarkable for the abundance and diversity of its microorganisms. An oligo- to mesosaline marsh occupied the core site before 9.5 ka B.P. Bangong was most likely closed. A sudden filling of the lake basin by dilute, nutrient-poor water occurs around 9.4 ka B.P. Maximum lake extent seems to have occurred around 9.4–8.7 ka B.P. Generally freshwater, relatively deep conditions were maintained up to 6.3 ka B.P., although interrupted by short-term regressive events between 8.6 and 7.5 ka B.P. A trend towards palustral conditions begins after 6.3 ka B.P. and the interval 3.9-3.2 ka B.P., rich in detrital organic material, coincides with an extremely low lake level. A last lacustrine episode of minor amplitude is recorded from about 3 to 2 ka B.P., before the closure of the system leading again to slightly saline conditions. The resemblances and synchronism between environmental changes recorded at Bangong and in Lake Sumxi, situated 200 km northwards and 800 m higher in elevation, indicate that regional climatic changes have been the major driving factor on ecological and hydrobiological changes in lakes of western Tibet.

Vehicle mass and road gradient are the important parameters for engine torque control, transmission shift scheduling and vehicle longitudinal control. It will add manufacturing cost to use more sensors to obtain these values. Therefore, there is increasing concern on the estimation methods of vehicle mass and road gradient based on the vehicle model. In this paper, on the premise of no additional sensors, the engine torque, engine speed, velocity, acceleration/brake/clutch pedal signals and gear from the CAN bus are used as the original data. The estimation methods of vehicle mass and road gradient are studied by applying vehicle dynamic, Luenberger state observer and Recursive Least Square with varying forgetting factors. Furthermore, the real time estimation arithmetic is validated through dSPACE/MicroAutoBox system on FAW J5 commercial vehicle.

A novel spectrofluorometric method for the determination of furosemide (FUR) is described. The method is based on enhancement of fluorescence emission of FUR in the presence of zinc (II) complexes of 1,4-bis(imidazol-1-ylmethyl)benzene. Under optimum conditions, the enhanced fluorescence intensity is linearly related to the concentration of FUR. The proposed method has been successfully applied to the determination of FUR in pharmaceutical preparations. The possible mechanism of this reaction is discussed briefly based on data from fluorescence spectroscopy, UV-vis absorption and infrared spectroscopy.

Though various cognitive radio schemes have been developed, they have not considered the problem of co-channel interference for cognitive users (CU) and primary user (PU)to share a OFDM channel, also well as MIMO-OFDM channel. This paper proposes a scheme that allows PU and CU share a same frequency band, while there are two problems to be solved: the interference of CU to PU, and interference of PU to CU. To solve the first problem, this paper proposes an ICA preceding scheme to cancel the interference of CU to PU, the preceding scheme involves the design of cognitive transmitters. To solve the second problem, this paper proposes CU receiver algorithm, we use inverse matrix to cancel the PU signal interference. The proposed scheme is not limited in the case that a MIMO-OFDM system of cognitive users in a wide spectrum range, and the primary user operates at a narrower channel bandwidth in overlap with the channel of the cognitive user. We designed an ICA CU system as a 2 × 2 MIMO OFDM system, while we need not change the PU systems' design. The simulation of the bit error rate of proposed ICA CU system verifies the proposed scheme.

This paper attempts an investigation on the impact of Chinas factor on the global commodity and ocean shipping freight volatilities in recent years. It measures Chinas contribution to the incremental demand growth for selected bulk commodities and ocean shipping in the world. Chinas impact on the price volatilities is statistically analyzed through a conventional econometric framework.

This paper documents China’s experience of transforming its food production and commerce from a centrally planned regime to a market system. The reforms have progressed in three steps: (a) raising agricultural procurement prices, (b) introducing market mechanisms to replace state controls, and (c) moving towards complete market operations. This series of reforms boosted agricultural production, raised per capita consumption of food products, and strengthened national food security. Agricultural price reforms in China in the past three decades suggest that right policies and institutions are essential in solving its food problems. Este artículo documenta la experiencia de China en la transformación de un sistema de producción de alimentos centralmente planificado a uno basado en el sistema de mercado. La reforma ha progresado en tres etapas: a) aumento de los precios agrícolas pagados por el Estado; b) introducción de los mecanismos de mercado; y c) avances hacia la realización total de operaciones de mercado. Esta serie de reformas incrementó la producción de alimentos y fortaleció la seguridad alimentaria nacional. Las reformas de precios agrícolas en China durante las tres décadas pasadas sugieren que las políticas correctas y las instituciones son esenciales para resolver los problemas alimentarios. Cet article est dédié à l’étude de la transformation connue par la production d’aliments en Chine comme conséquence du passage, d’un système de planification central, à un système de marché. Les dites réformes ont été menées en trois étapes: a) Augmentation des prix agricoles payés par l’État; b) introduction des mécanismes de marché; et c) avancements vers la réalisation totale des opérations sur la base des principes de marché. Cette transformation vers un système marchande a stimulé l’accroissement de la production d’aliments. D’ailleurs, elle a renforcé la sécurité alimentaire nationale. Le bilan des réformes des prix agricoles en Chine pendant les trois dernières décennies montre que les politiques correctes et la performance des institutions sont des éléments essentiels pour résoudre les problèmes alimentaires.

An intelligent microprocessor based TLD reader Model RGD-3 has been developed for routine TLD monitoring and other TL related measurement.With various optimizd designs, the TLD reader shows its high versatility, stability, reliability and especially its good environmental adaptability in the hot and wet climates. The performance of the RGD-3 TLD reader meets all the requirements of the International Standard (IEC-166: 1991) for the “Thermoluminescence Dosimetry system for Personal & Environmental Monitoring”. Its high benefit-cost ratio affords great potential for use especially in developing countries.

The cefazolin can be detected according to the change of solution color resulting from the plasmonic resonance absorption of AuNPs.The absorbance ratio at 520/660 nm of AuNPs is proportional to the concentration of cefazolin in the range of 0.1~5.0 μmol/L with the detection limit of 14 nmol/L.This method could be extended to the determination of cefazolin sodium powder injection,the recovery of cefazolin was in the range of 97.4%~100.2% while the relative standard deviation was less than 6.1%.

Apolipoprotein-E (ApoE) has been implicated in Alzheimer’s disease, atherosclerosis, and other unresolvable inflammatory conditions but a common mechanism of action remains elusive. We found in ApoE-deficient mice that oxidized lipids activated the classical complement cascade (CCC), resulting in leukocyte infiltration of the choroid plexus (ChP). All human ApoE isoforms attenuated CCC activity via high-affinity binding to the activated CCC-initiating C1q protein (KD~140–580 pM) in vitro, and C1q–ApoE complexes emerged as markers for ongoing complement activity of diseased ChPs, Aβ plaques, and atherosclerosis in vivo. C1q–ApoE complexes in human ChPs, Aβ plaques, and arteries correlated with cognitive decline and atherosclerosis, respectively. Treatment with small interfering RNA (siRNA) against C5, which is formed by all complement pathways, attenuated murine ChP inflammation, Aβ-associated microglia accumulation, and atherosclerosis. Thus, ApoE is a direct checkpoint inhibitor of unresolvable inflammation, and reducing C5 attenuates disease burden. ApoE is a direct checkpoint inhibitor of unresolvable inflammation in neurodegenerative and cardiovascular diseases