This finding suggests that THP-1 cells are well differentiated by 5 ng/ml PMA, and that the resulting differentiated macrophages respond well to secondary weak stimuli without being overwhelmed by undesirable gene upregulation induced by PMA.

Summary.  Background: In Asian patients undergoing surgery, the incidence of venous thromboembolism (VTE) is thought to be low relative to Western patients, and the routine use of thromboprophylaxis is controversial. Objectives: The aim of this work was to study the epidemiology of VTE in Asian patients undergoing orthopedic surgery without thromboprophylaxis. Patients and methods: We performed a prospective observational study of a cohort of consecutive Asian patients hospitalized for total hip or knee replacement or hip fracture surgery without thromboprophylaxis. The primary study outcome was the incidence of the composite of symptomatic VTE or sudden death at hospital discharge. This outcome was also assessed at 1 month's follow‐up. Results: Between April 2001 and July 2002, 2420 patients were enrolled. Median age was 68 years and the median duration of hospital stay was 13 days. The rate of symptomatic VTE or sudden death as notified by investigators was 2.3%[55 patients, 99% confidence interval (CI) 1.6, 3.2] and 1.2% (28 patients, 99% CI 0.7, 1.8) after adjudication by an independent committee. Chronic heart failure, varicose veins and a history of VTE were independent risk factors (P < 0.05) for the occurrence of the primary endpoint. At 1 month's follow‐up, the incidence of adjudicated symptomatic VTE or sudden death was 1.5% (35/2264 patients). Conclusion: In Asian patients, the incidence of symptomatic VTE after major orthopedic surgery is not low, consistent with the rates observed in Western countries. The use of thromboprophylaxis should be considered in Asian patients undergoing such high‐risk surgical procedures.

Vascularized fibular grafting has been used for treatment of osteonecrosis of the femoral head and although some reports demonstrate successful short- to mid-term outcomes, long-term results are still unknown. We retrospectively reviewed 135 patients (151 hips) who underwent vascularized fibular grafting for osteonecrosis of the femoral head. One-hundred and ten patients (124 hips) were followed for a minimum 10 years (mean, 13.9 years; range, 10-23.7 years). The mean Harris hip score improved from 72 to 88. At the latest followup, we found improved or unchanged radiographs in 37 of 59 hips initially Stage II hips and 39 of 65 Stage III hips. Thirteen hips (13 patients) (10.5%) failed treatment and underwent total hip arthroplasty. The location and size of the necrotic lesion and the patient's age influenced long-term survival of the graft. Postoperative complications included clawing of the big toe in 17 patients, partial peroneal nerve palsy in two, and superficial infection in two. Subtrochanteric fracture occurred in two hips. The data suggest free vascularized fibular grafting was successful in maintaining joint function and delaying the need for joint replacement procedure. Graft survival was associated with the patient's age and size and location of the lesion but not etiology and stages of the disease.

In lithium ion battery composite anodes that are derived from graphite particles bound together by a polymeric binder of 5-7 wt %, it is well-known that the type and content of the binder influence the formation of a solid electrolyte interphase and the electrochemical behavior. However, the nature of the interaction between the graphite particles and binder has not been extensively studied. We describe here the interaction of poly(vinylidene fluoride) (PVDF) with graphite based on the characteristics of the precursor slurry and the surface chemistry and morphology of the final composite anodes. The slurry was characterized by dynamic viscosity measurements and the solid composite by atomic force microscopy, lateral force microscopy, electron probe X-ray microanalysis, and X-ray photoelectron spectroscopy. The final film properties correlate with the suspension viscosity, which varies over 6 orders of magnitude for eight different carbon samples. In the composite film, PVDF preferentially deposits on the edges and grain boundaries of the graphite particles with a maximum of 40% of the surface of graphite being covered by the polymer. We correlate an increase in the homogeneity of the PVDF distribution in the final composite film with an increase in the slurry viscosity and interpret this observation in terms of PVDF/graphite interaction.

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We have determined the dependence of the surface distribution of poly(vinylidene fluoride) (PVDF) on molecular weight and functionality of PVDF and solvent evaporation kinetics in a graphite composite film analogous to that used as an anode in a lithium ion battery. The homogeneity of the PVDF surface distribution on the graphite particles is determined from fluorine dot mappings, which are detected using energy-dispersive spectroscopy and electron probe X-ray microanalysis. The results are quantified with a standard deviation method and a spatial autocorrelation function approach, which yield consistent results. We have also examined the electrochemical performance of the anodes with cyclic voltammetry and impedance spectroscopy and correlated the electrochemical properties with the homogeneity of PVDF distribution in the final film. Hydroxyl-modified PVDF shows more homogeneous distribution compared to unmodified PVDF. Furthermore, the homogeneity of PVDF distribution on the graphite increases as the solvent evaporation rate increases. Samples with homogeneous PVDF distribution show higher electrochemical capacity and lower resistance, which can be explained in terms of solid electrolyte interphase film formation, binding capability, binder swelling, and electrochemically active sites of the modified PVDF.

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