Tropical pyomyositis

A 22 year old male presented with symptoms of diffuse muscle pain and multiple abnormal laboratory findings that were eventually attributed to tropical myositis. Computed tomography scan was more reliable than ultrasound and served as a guide to needle aspiration and pathologic diagnosis.     

Alpha-thalassemia in two Mediterranean populations

We used restriction endonuclease analysis to determine the incidence of alpha-thalassemia in two Mediterranean islands. In a random population sample, the gene frequency of deletion-type alpha-thalassemia-2 (- alpha) was 0.18 in Sardinians and 0.07 in Greek Cypriots. All cases were the rightward crossover type. From these frequencies and the known incidence of hemoglobin-H disease in these populations, we calculated the frequency of the alpha-thalassemia-1 genotype (--) and determined that it was low. We also found that beta-thalassemia homozygotes in sardinia have a higher incidence of alpha-thalassemia than normals and beta thalassemia heterozygotes because a significantly greater number of these homozygotes are also homozygous for the alpha-thalassemia-2 lesion. These findings support the theory that coinheritance of alpha- thalassemia mitigates the severity of beta-thalassemia and suggest that the protection is most pronounced when two alpha-globin genes are deleted.     

Altered expression of the adenine nucleotide translocase isoforms and decreased ATP synthase activity in skeletal muscle mitochondria in heart failure

Exercise intolerance is a component of heart failure (HF) syndrome. We aimed to identify the defects in skeletal muscle mitochondria which may contribute to the development of peripheral myopathy. Subsarcolemmal (SSM) and interfibrillar (IFM) mitochondria were isolated from gastrocnemius muscle of control dogs (N = 5) and dogs with pacing-induced HF (N = 5). The measurement of integrated mitochondrial function (oxidative phosphorylation) and of individual activities of mitochondrial electron transport chain (ETC) complexes was complemented with the assessment of the amount and activity of the components of the phosphorylation apparatus. Both populations of skeletal muscle mitochondria isolated from HF have significantly decreased ADP-stimulated (state 3) respiratory rates with complex I, II and III substrates. The decrease in respiratory rates of skeletal muscle SSM are neither relieved upon collapsing the mitochondrial potential with an uncoupler nor increased in the presence of maximal ADP concentrations showing a defect in the ETC, which needs further investigation. In contrast, respiratory rates of skeletal muscle IFM from HF were relieved with the uncoupler and partially improved in the presence of maximal ADP concentrations. In these IFM, alterations in the phosphorylation apparatus were detected with a decreased amount of ANT isoform 2 and increased amount of isoform 1. The IFM dysfunction may be explained by this shift in ANT isoforms. In conclusion, pacing-induced HF causes a decrease in the oxidative phosphorylation of skeletal muscle mitochondria due to defects in the ETC and phosphorylation apparatus.     

Clinical controversy in orbitary cholesteatoma

Cholesterol granulomas are tumor-like lesions very rarely encountered in the orbital, frontal sinus, and maxillary sinus sites but with higher frequency in the middle-ear and petrous apex. Theoretically, cholesterol granulomas develop as a reaction to localized hemorrhages, often occurring in bony sites with no blood and blood products drainage. We present 5 cases with exophthalmoses, namely, 3 cases with granuloma and 2 cases with cholesteatoma, all being characterized by the presence of cholesterol spikes at the histologic examination. Henderson (Orbital tumors. 3rd ed. New York: Raven Press; 1994) reports cholesterol spikes in medical literature as structures with different histologic names as hematic cyst, intraorbital hematoma, subperiostal hemorrhages, chocolate cyst, and xanthomatosis reactive lesions of bone. In fact, cholesterol granuloma is the term for the pocket of hematogenous debris found in the frontal bone at surgery. We try to review the spectrum of clinical-pathological and radiographic features that characterize cholesterol granuloma but with the same surgical way management.     

An EPID response calculation algorithm using spatial beam characteristics of primary, head scattered and MLC transmitted radiation

We have developed an independent algorithm for the prediction of electronic portal imaging device (EPID) response. The algorithm uses a set of images [open beam, closed multileaf collimator (MLC), various fence and modified sweeping gap patterns] to separately characterize the primary and head-scatter contributions to EPID response. It also characterizes the relevant dosimetric properties of the MLC: Transmission, dosimetric gap, MLC scatter [P. Zygmansky et al., J. Appl. Clin. Med. Phys. 8(4) (2007)], inter-leaf leakage, and tongue and groove [F. Lorenz et al., Phys. Med. Biol. 52, 5985-5999 (2007)]. The primary radiation is modeled with a single Gaussian distribution defined at the target position, while the head-scatter radiation is modeled with a triple Gaussian distribution defined downstream of the target. The distances between the target and the head-scatter source, jaws, and MLC are model parameters. The scatter associated with the EPID is implicit in the model. Open beam images are predicted to within 1% of the maximum value across the image. Other MLC test patterns and intensity-modulated radiation therapy fluences are predicted to within 1.5% of the maximum value. The presented method was applied to the Varian aS500 EPID but is designed to work with any planar detector with sufficient spatial resolution.     

The long-term effectiveness of generic adult fixed-dose combination antiretroviral therapy for HIV-infected Ugandan children

Background

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

Objective

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

Methods

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

Results

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.

Conclusion

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.