Injury control: an opportunity for China

Injury control is an important health issue in China, but has been less well explored than in other countries. To encourage health policy makers to give greater attention to injury control, this report highlights the great damage caused by injuries and the neglected status of injury control in China. China's situation and the experiences and lessons from industrialized countries, especially the USA, are summarized. Finally, two opportunities to improve injury control in China are identified: establishment of a mechanism for multi-department coordination and collaboration; and improvement of injury data surveillance.

Electrochemical Assay of Human Islet Amyloid Polypeptide and Its Aggregation

Square wave voltammetry is used in this work to detect human islet amyloid polypeptide (hIAPP) by using the oxidized signal of the tyrosine residue in hIAPP. A detection limit of 1×10^-6 M for hIAPP has been obtained. A kinetic study of the aggregation process has been carried out according to the relationship between the anodic peak current in the square wave voltammograms of hIAPP and the incubation period. The results show that the nucleation starts in the first hour of incubation and then, during the next two hours, aggregation may occur rapidly. hIAPP can therefore be monitored with a label-free electrochemical method with low detection limit and high sensitivity. This electrochemical method can be also utilized to study the kinetics of hIAPP aggregation, and it may be also employed to study the conformational changes of the polypeptide.

In vivo cartilage contact deformation in the healthy human tibiofemoral joint

OBJECTIVES

In vivo cartilage contact deformation is instrumental for understanding human joint function and degeneration. This study measured the total deformation of contacting articular cartilage in the human tibiofemoral joint during in vivo weight-bearing flexion.

METHODS

Eleven healthy knees were magnetic resonance (MR) scanned and imaged with a dual fluoroscopic system while the subject performed a weight-bearing single-leg lunge. The tibia, femur and associated articulating cartilage were constructed from the MR images and combined with the dual fluoroscopic images to determine in vivo cartilage contact deformation from full extension to 120 degrees of flexion.

RESULTS

In both compartments, minimum peak compartmental contact deformation occurred at 30 degrees of flexion (24 +/- 6% medial, 17 +/- 7% lateral) and maximum peak compartmental deformation occurred at 120 degrees of flexion (30 +/- 13% medial, 30 +/- 10% lateral) during the weight-bearing flexion from full extension to 120 degrees. Average medial contact areas and peak contact deformations were significantly greater than lateral compartment values (P < 0.05). In addition, cartilage thickness in regions of contact was on average 1.4- and 1.1-times thicker than the average thickness of the tibial and femoral cartilage surfaces, respectively (P < 0.05).

CONCLUSIONS

These data may provide base-line knowledge for investigating the effects of various knee injuries on joint contact biomechanics and the aetiology of cartilage degeneration.

Anomalous line shape of the cross section for e{+}e{-}--> hadrons in the center-of-mass energy region between 3.650 and 3.872 GeV

We observe an obvious anomalous line shape of the e;{+}e;{-}--> hadrons total cross sections in the energy region between 3.700 and 3.872 GeV. It is inconsistent with the explanation for only one simple psi(3770) resonance with a statistical significance of 7sigma. The anomalous line shape may be explained by two possible enhancements of the inclusive hadron production near the center-of-mass energies of 3.764 and 3.779 GeV, indicating that either there is likely a new structure in addition to the psi(3770) resonance around 3.773 GeV, or there are some physics effects reflecting the DD[over ] production dynamics.

Probing the superconducting energy gap from infrared spectroscopy on a Ba0.6K0.4Fe2As2 single crystal with Tc=37 K

We performed optical spectroscopy measurement on a superconducting Ba0.6K0.4Fe2As2 single crystal with T{c}=37 K. Formation of the superconducting energy gaps in the far-infrared reflectance spectra below T{c} is clearly observed. A flat and close to unity reflectance is observed roughly below 150 cm;{-1} for T<<T{c}, following an s-wave pairing line shape. A more rapid decrease occurs near 200 cm;{-1}, leading to a peak in the ratio of the reflectance at T<<T{c} over that for T>or=T{c}. We determined the absolute value of the penetration depth at 10 K as lambda approximately 2000+/-80 A. A spectral weight analysis shows that the Ferrell-Glover-Tinkham sum rule is satisfied at low energy scale, less than 6Delta.

Postprandial blood glucose response to a standard test meal in insulin-requiring patients with diabetes treated with insulin lispro mix 50 or human insulin mix 50

AIM

To compare the 2-h postprandial blood glucose (PPBG) excursion following a standard test meal in insulin-requiring patients with diabetes treated twice daily with human insulin mix 50 vs. insulin lispro mix 50 (LM50).

METHODS

This was a multicentre, randomised, open-label, crossover comparison of two insulin treatments for two 12-week treatment periods in 120 Chinese patients. One- and 2-h PPBG and excursion values were obtained following a standardised test meal. Fasting blood glucose (FBG), haemoglobin A1c (HbA1c), insulin dose, rate of hypoglycaemia and safety data were obtained. A crossover analysis using SAS Proc MIXED was employed.

RESULTS

Mean 2-h PPBG excursion decreased from 6.32 +/- 3.07 mmol/l at baseline to 3.47 +/- 2.97 mmol/l at end-point in the LM50 group, and from 6.31 +/- 2.88 at baseline to 5.02 +/- 3.32 mmol/l at end-point in the human insulin mix 50 group (p < 0.001). Two-hour PPBG (p = 0.004) and 1-h PPBG excursion (p < 0.001) were significantly lower with LM50 as compared with human insulin mix 50. Both treatment groups were equivalent for HbA1c control, 1-h PPBG and insulin dose requirements. Mean FBG was higher with LM50 than with human insulin mix 50 (p = 0.023). The overall incidence of treatment-emergent adverse events and hypoglycaemia rate per 30 days were similar between treatment groups.

CONCLUSIONS

Insulin lispro mix 50 provided better postprandial glycaemic control compared with human insulin mix 50 while providing the convenience of injecting immediately before meals. Both treatments were generally well tolerated by all randomly assigned patients.

Inhibition of metastasis to lung of a human nasopharyngeal carcinoma cell line CNE- 2L2 transfected with pRc/ CMV-antisense 6A8 cDNA in nude mice

The growth of CNE-2L2 cell, a cloned line of human nasopharyngeal carcinoma with a high potentiality of metastasis to lung was inhibited to a certain extent after transfection with a recombinant antisense expression vector of a cDNA encoding a human alpha-mannosidase (pRc/CMV-antisense 6A8 cDNA) (the Genbank accession number of 6A8 cDNA is U37248) in comparison with that of the cell transfected with the Mock and of the wild cell. Two months after a subcutaneous inoculation of CNE-2L2 cell into the axilla of nude mice metastatic lesions in the lung were observed in 9/10 mice (90%) with grade III in 8 mice and grade II in one mouse in the wild cell group, in 6/8 mice (75 %) with grade III in one mouse, grade II in 2 mice and grade I in 3 mice in the Mock-transfection group, in only 3/10 mice (30%) with all grade I in pRc/CMV-antisense 6A8 cDNA-transfection group.

Combination of aptamer with gold nanoparticles for electrochemical signal amplification: application to sensitive detection of platelet-derived growth factor

In this paper, we report a novel electrochemical detection approach for platelet-derived growth factor (PDGF) via "sandwich" structure and gold nanoparticles (Au-NPs) mediated amplification technique. The "sandwich" structure is fabricated based on the fact that PDGF has two aptamer-binding sites, which makes it possible for one PDGF molecule to connect with two aptamers simultaneously. It is found that this electrochemical system with "sandwich" structure and Au-NPs can significantly amplify the signal of electrochemical probe [Ru(NH(3))(5)Cl](2+) for PDGF detection, and thus increase the detection sensitivity significantly. As a result, this PDGF detection approach obtains an extraordinarily low detection limit of 1 x 10(-14)M for purified samples, 1 x 10(-12)M for contaminated-ridden samples or undiluted blood serum. This detection approach can also exhibit good stability and excellent specificity.

Segmentation of touching cell nuclei using gradient flow tracking

Reliable cell nuclei segmentation is an important yet unresolved problem in biological imaging studies. This paper presents a novel computerized method for robust cell nuclei segmentation based on gradient flow tracking. This method is composed of three key steps: (1) generate a diffused gradient vector flow field; (2) perform a gradient flow tracking procedure to attract points to the basin of a sink; and (3) separate the image into small regions, each containing one nucleus and nearby peripheral background, and perform local adaptive thresholding in each small region to extract the cell nucleus from the background. To show the generality of the proposed method, we report the validation and experimental results using microscopic image data sets from three research labs, with both over-segmentation and under-segmentation rates below 3%. In particular, this method is able to segment closely juxtaposed or clustered cell nuclei, with high sensitivity and specificity in different situations.

Preparation of biofilm electrode with Xanthomonas sp. and carbon nanotubes and the application to rapid biochemical oxygen demand analysis in high-salt condition

A Xanthomonas sp. was isolated from the sludge on the drain outlet of a pharmaceutical factory. Then, the bacterium and carbon nanotubes (CNTs) were co-attached to an oxygen electrode for rapid analysis of biochemical oxygen demand (BOD). The response current was linear with BOD values in the range 10 to 300 mg/L for standard BOD solution with a response time of 35 seconds (R = 0.9994) and 20 to 580 mg/L for pharmaceutical wastewater with a response time < or =200 seconds (R = 0.9985), which means that this modified electrode might be used for online BOD analysis of pharmaceutical wastewater. Further studies revealed that the modified electrode can be used for BOD measurement in a high-salt condition. Also, the bacterium/CNTs biofilm can maintain its activity and good performance, even after being sealed and stored at 4 degrees C for 50 days.

Superconducting properties of the Fe-based layered superconductor LaFeAsO0.9F0.1-delta

We have employed a new route to synthesize single phase F-doped LaOFeAs compound and confirmed the superconductivity above 20 K in this Fe-based system. We show that the new superconductor has a rather high upper critical field of over 50 T. A clear signature of superconducting gap opening below T(c) was observed in the far-infrared reflectance spectra, with 2Delta/kT(c) approximately 3.5-4.2. Furthermore, we show that the new superconductor has electron-type conducting carriers with a rather low-carrier density.

Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO1-xFxFeAs

A series of layered CeO1-xFxFeAs compounds with x=0 to 0.20 are synthesized by the solid state reaction method. Similar to the LaOFeAs, the pure CeOFeAs shows a strong resistivity anomaly near 145 K, which was ascribed to the spin-density-wave instability. F doping suppresses this instability and leads to the superconducting ground state. Most surprisingly, the superconducting transition temperature could reach as high as 41 K. Such a high T_{c} strongly challenges the classic BCS theory based on the electron-phonon interaction. The closeness of the superconducting phase to the spin-density-wave instability suggests that the magnetic fluctuation plays a key role in the superconducting pairing mechanism. The study also reveals that the Ce 4f electrons form local moments and are ordered antiferromagnetically below 4 K, which could coexist with superconductivity.

GABA-mediated inhibition correlates with orientation selectivity in primary visual cortex of cat

Orientation selectivity is an important emergent property of neurons in the primary visual cortex, and inhibition is thought to play an important role in establishing this selectivity. But the relationship between strength of inhibition and orientation selectivity is unclear. To investigate this relationship, we electrophoretically applied the inhibitory transmitter GABA and the GABA(A) antagonist bicuculline on the same individual area 17 neurons in anesthetized cats. Neurons were classified as weakly orientation-selective, moderately orientation-selective, or strongly orientation-selective, according to the values of an orientation bias index. Orientation bias, half-width of the tuning curve at half-height and an orientation-specificity index (orthogonal to optimal ratio) were compared with or without GABA and bicuculline administration. GABA improved orientation selectivity with the greatest effects on weakly orientation-selective cells, smaller effects on moderately orientation-selective cells, and minimal effects on strongly orientation-selective cells; bicuculline diminished orientation selectivity the most on moderately and strongly orientation-selective cells, with minimal effects on weakly orientation-selective cells. We also found that orientation selectivity correlated with the level of neurons' spontaneous activity. These results suggest that the degree of orientation selectivity of an area 17 neuron correlates with its endogenous inhibition strength, and that GABAergic inhibition can bi-directionally regulate orientation selectivity. This correlation indicates that GABA-mediated inhibition plays an important role in establishing sharp orientation selectivity of individual neurons.

The metal-insulator-like and insulator-metal-like behaviors in antimony

The resistivity and Hall resistivity of semimetallic antimony were measured from 2 to 300 K in magnetic fields up to 14 T. We found that in low field, the resistivity shows metallic behavior. In a modest field, the resistivity decreases to a minimum and then increases with decreasing temperature, showing a metal-insulator-like transition. In high field, the resistivity drops at low temperatures, showing an insulator-metal-like transition. The metal-insulator-like behavior can be explained by the competition of zero field resistivity and magneto-resistance, which is reciprocal to the zero field resistivity. The insulator-metal-like behavior can be explained by the imbalance of two carrier densities which changes the magneto-resistance from being reciprocal to proportional to the zero field resistivity.