Pyomyositis in childhood: a case report

Pyomyositis is a primary infection of skeletal muscle. We report the case of a previously healthy six-year-old who suffered from pyomyositis in the right lower back. He presented with lower back pain and low-grade fever for one week. After a series of laboratory and imaging studies, the diagnosis of right multifidus muscle pyomyositis with abscess formation was made. The patient recovered rapidly after incision and drainage therapy, accompanied by antibiotic treatment. Methicillin-resistant Staphylococcus aureus was cultured from the abscess discharge. It was strongly suspected that herbal medicines and common cold medication the patient had been prescribed before admission to our hospital produced a masking effect that delayed the diagnosis.     

Anti-GBM glomerulonephritis in mice lacking nitric oxide synthase type 2

To determine the relationship between quantitative Doppler parameters of portal, hepatic, and splanchnic circulation and hepatic venous pressure gradient (HVPG), variceal size, and Child-Pugh class in patients with alcoholic cirrhosis, we studied forty patients with proved alcoholic cirrhosis who underwent Doppler ultrasonography, hepatic vein catheterization, and esophagoscopy. The following Doppler parameters were recorded: time-averaged mean blood velocity, volume flow of the main portal vein flow, and resistance index (RI) of the hepatic and of the superior mesenteric artery. Doppler findings were compared with HVPG, presence and size of esophageal varices, and Child-Pugh class. There was a significant inverse correlation between portal velocity and HVPG (r = -.69), as well as between portal vein flow and HVPG (r = -.58). No correlation was found between RI in the hepatic artery or superior mesenteric artery and HVPG. No correlation was found between portal vein measurements and presence and size of varices. Severe liver failure was associated with lower portal velocity and flow. In patients with alcoholic cirrhosis, only portal vein blood velocity and flow, but neither hepatic nor mesenteric artery RI, are correlated to the severity of portal hypertension and to the severity of liver failure.     

Postbuckling of Axially Loaded Functionally Graded Cylindrical Panels with Piezoelectric Actuators in Thermal Environments

A compressive postbuckling analysis is presented for a functionally graded cylindrical panel with piezoelectric actuators subjected to the combined action of mechanical, electrical, and thermal loads. The temperature field considered is assumed to be of uniform distribution over the panel surface and through the panel thickness and the electric field considers only the transverse component EZ. The material properties of the presently considered functionally graded materials (FGMs) are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents, whereas the material properties of the piezoelectric layers are assumed to be independent of the temperature and the electric field. The governing equations are based on a higher-order shear deformation theory with a von Kármán-Donnell-type of kinematic nonlinearity. A boundary layer theory for shell buckling is extended to the case of hybrid FGM cylindrical panels of finite length. The nonlinear prebuckling deformations and initial geometric imperfections of the panel are both taken into account. A singular perturbation technique is employed to determine the buckling loads and postbuckling equilibrium paths. The numerical illustrations concern the compressive postbuckling behavior of perfect and imperfect FGM cylindrical panels with fully covered piezoelectric actuators, under different sets of thermal and electrical loading conditions. The effects due to temperature rise, volume fraction distribution, applied voltages, panel geometric parameters, in-plane boundary conditions, as well as initial geometric imperfections are studied.     

HIV infection among male prisoners in South Australia, 1989 to 1994

The prevalence of human immunodeficiency virus (HIV) in male prisoners in South Australia from July 1989 to June 1994 was ascertained from a repeated cross-sectional study. We also compared the criminological and demographic characteristics and histories of drug use of 39 HIV-infected prisoners and a randomly selected sample of 86 uninfected prisoners admitted at the same time. The numbers of HIV-infected prisoners in prison in any month ranged from 4 to 12. Prevalence among the total prison population ranged from 0.4 per cent to 1.4 per cent, and among the subpopulation of injecting drug users from 1.25 per cent to 4.36 per cent. Many HIV-infected prisoners continued after their diagnosis to have lifestyles that resulted in imprisonment. Infected prisoners were significantly older, had spent longer in prison and were more likely to be users of heroin (OR = 13.1) and methadone (OR = 25.4) than controls. Infection with HIV among South Australian prisoners has been continuous since at least the mid-1980s. The recidivism among many of the infected prisoners contributes to the variation in prevalence but also raises concerns about their management. Greater effort to minimise the recidivism of the HIV-infected prisoners could reduce the prevalence of HIV in the prison population.     

Finite element piezothermoelasticity analysis and the active control of FGM plates with integrated piezoelectric sensors and actuators

 An efficient finite element model is presented for the static and dynamic piezothermoelastic analysis and control of FGM plates under temperature gradient environments using integrated piezoelectric sensor/actuator layers. The properties of an FGM plate are functionally graded in the thickness direction according to a volume fraction power law distribution. A constant displacement-cum-velocity feedback control algorithm that couples the direct and inverse piezoelectric effects is applied to provide active feedback control of the integrated FGM plate in a closed loop system. Numerical results for the static and dynamic control are presented for the FGM plate, which consists of zirconia and aluminum. The effects of the constituent volume fractions and the influence of feedback control gain on the static and dynamic responses of the FGM plates are examined. Received: 13 March 2002 / Accepted: 5 March 2003 The work described in this paper was supported by a grant awarded by the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. CityU 1024/01E).     

Role of base plate rotational speed in controlling spheroid size distribution and minimizing oversize particle formation during spheroid production by rotary processing

The occurrence of material adhesion and formation of oversize particles in the product yield during one-pot spheroid production by rotary processing leads to a less predictable process and a decrease in the usable portion of the total product yield obtained from each production run. The use of variable speeds of the rotating frictional base plate during the spheronization run was investigated for achieving optimal spheroid production. When the base plate speed was increased during liquid addition, the greater centrifugal forces generated improved liquid distribution and the mixing of the moist powder mass, resulting in a decrease in the amount of oversize particles formed. When the base plate was maintained at a high speed throughout the run, the amount of oversize particles and mean spheroid size increased, and a greater “between batch” mean spheroid size variability was also observed. The findings showed that, when higher speeds were used, the residence time must be adjusted accordingly to avoid excessive coalescence and growth while maintaining even liquid distribution. A “low-high-low” speed variation during rotary processing may be used to produce spheroids with a narrow size distribution and with a minimal amount of oversize particles in the total product yield.     

Clinical Evaluation of Burn Injuries Using an Optical Reflectance Technique

In a multiyear clinical study, the authors tested the reliability of an optical technique for diagnosing tissue damage on burn wounds. Optical reflectivity was measured using a convenient, bedside, noninvasive instrument (the Burn Depth Indicator), which was designed and built by one of the authors. The results show that this optical technique is more accurate than conventional methods for predicting the healing time of burn wounds which are otherwise difficult to assess. The optical properties of burn wounds were modeled using a three layer Kubelka-Munk model. We found that eschar thickness and the volume fraction and oxygen saturation of blood in the dermis determine the optical properties of the burn. These factors, in turn, are known to correlate with the burn depth and healing potential.     

The use of taped skin closure in orthopaedic wounds

Currently, there are two methods of cervical conization, the laser and the cold knife. This retrospective review examined 217 laser cases and 205 cold knife cases to see which method was superior. The cold knife was shown to have a shorter operative time and a lower overall cost to the patient; however, it was associated with more intraoperative blood loss and more overnight admissions for observation. There were no differences in post operative bleeding complications requiring a visit to the emergency room or to the operating room. It is concluded that overall, there is no clearly superior method of conization for the treatment of cervical intra-epithelial neoplasia.