[Biomechanical analysis of four internal fixations for Pauwels â ¢ femoral neck fractures with defects].

OBJECTIVE: To investigate the biomechanical characteristics of different internal fixations for Pauwels type Ⅲ femoral neck fracture with defect, and provide reference for the treatment of femoral neck fracture. METHODS: Three-dimensional (3D) finite element models of femoral neck fractures were established based on CT images, including fracture and fracture with defects. Four internal fixations were simulated, namely, inverted cannulated screw(ICS), ICS combined with medial buttress plate, the femoral neck system (FNS) and FNS combined with medial buttress plate. The von Mises stress, model stiffness and fracture displacements of fracture models under 2 100 N axial loads were measured and compared. RESULTS: When femoral neck fracture was fixed by ICS and FNS, the peak stress was mainly concentrated on the surface of the screw near the fracture line, and the peak stress of FNS is higher than that of ICS;When the medial buttress plate was combined, the peak stress was increased and transferred to medial buttress plate, with more obvious of ICS fixation. For the same fracture model, the stiffness of FNS was higher than that of ICS. Compared with femoral neck fracture with defects, fracture model showed higher stiffness in the same internal fixation. The use of medial buttress plate increased model stiffness, but ICS increased more than FNS. The fracture displacement of ICS model exceeded that of FNS. CONCLUSION: For Pauwels type Ⅲ femoral neck fracture with defects, FNS had better biomechanical properties than ICS. ICS combined with medial buttress plate can better enhance fixation stability and non-locking plate is recommended. FNS had the capability of shear resistance and needn't combine with medial buttress plate.

[Characterization and Exposure Risk Assessment of Non-phthalate Plasticizers in House Dust from Guangzhou].

Although non-phthalate plasticizers are widely used in various consumer products as substitutes for phthalates, currently little is known about their environmental occurrence and the risks of human exposure. To characterize the pollution and human exposure risk in indoor environments, house dust samples collected from 83 households in Guangzhou were analyzed for twelve typical non-phthalate plasticizers. Results showed that dioctyl terephthalate (DEHT), trioctyl trimellitate (TOTM), acetyl lemon tributyl ester (ATBC), heptylnonyl adipate, di(2-ethylhexyl) adipate, and trioctyl trimellitate were detected in all samples. The total concentrations of non-phthalate plasticizers ranged from 22.4 to 615 µg ·g-1 with a median of 101 µg ·g-1. DEHT had the highest concentrations (9-487 µg ·g-1), followed by TOTM (0.3-87 µg ·g-1) and ATBC (1.7-50 µg ·g-1). Daily intakes via dust ingestion for adults and children were estimated based on the dust concentrations. The total daily intake of children was 367 ng ·(kg ·d)-1, which was 8-9 times higher than that of adults[43 ng ·(kg ·d)-1]. Further risk assessment through the hazard quotient approach showed that the exposure of adults and children to non-phthalic plasticizers via dust ingestion was within an acceptable risk range.

Epalrestat protects against diabetic peripheral neuropathy by alleviating oxidative stress and inhibiting polyol pathway.

Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.

Genome Sequence of an Extensively Drug-Resistant Strain of Klebsiella pneumoniae, Strain YN-1, with Carbapenem Resistance.

The emergence and spread of multidrug-resistant (MDR) Klebsiella pneumoniae has been regarded as one of the major challenges among health care-associated infections worldwide. Here, we report the draft genome sequence of an extensively drug-resistant (XDR) K. pneumoniae strain isolated in 2013 from Yunnan Province, China.

Genome Sequence of a Pandrug-Resistant Pseudomonas aeruginosa Strain, YN-1.

A highly rampant multidrug-resistant strain of Pseudomonas aeruginosa appeared in a hospital in Yunnan Province, China. Here, we report the genome sequence of the pandrug-resistant (PDR) P. aeruginosa strain recovered from a patient in 2013.