Diagnostic thoracic-computed tomography in radiotherapy for loco-regional recurrent breast carcinoma

OBJECTIVE: To define the composition of cytoplasmic inclusions forming stacks and concentric whorls in histiocytes and mesothelial cells of serous fluids, imparting to them a resemblance to Gaucher cells, and to draw conclusions on the mechanism of their formation. STUDY DESIGN: Three serous fluids (one pleural and two pericardial) containing a fair number of the cells referred to were progressively subjected to the following studies: (1) cytochemistry for mucopolysaccharides, proteins, phospholipids and hemoglobin; (2) immunocytochemistry for immunoglobulins IgA, IgG, IgM and lysozyme; (3) transmission electron microscopy (TEM), and (4) scanning electron microscopy-based energy dispersive X-ray microanalysis (SEM-EDAX). RESULTS: All three specimens were blood stained and contained large numbers of histiocytes and mesothelial cells, arranged singly and in groups, with abundant cytoplasmic inclusions. The inclusions stained strongly positive for phospholipids, weakly positive for hemoglobin and negative for all other substances examined by cytochemistry and immunocytochemistry. By TEM the inclusions had a concentric lamellar membranous structure, reminiscent of myelinosomes or lamellar bodies of lipid-forming or -storing cells. There was also phagocytosis by histiocytes and mesothelial cells of red blood cells, which were mostly in a degenerated state. SEM-EDAX of inclusion-bearing cells showed a modest peak for phosphorus and a variable but small peak for iron, which corroborated the cytochemical and TEM findings. CONCLUSION: Since there was not metabolic or other systemic disease in the patients to account for these cells, we posit that phospholipids derived from cell membranes of phagocytized cells, especially red blood cells, provide the building blocks for the formation of such inclusions as they enter the metabolic pathway of phagocytic cells (mesothelial cells and histiocytes) and appear in their lysosomal structures. It is advantageous for cytologists to be familiar with significance of such changes and not to mistake them for metabolic or other systemic disease.     

Human neutrophils secrete vascular endothelial growth factor

Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that plays a pivotal role in mediating neovascularization as well as other endothelial cell alterations during inflammation. In this study, we demonstrate that human neutrophils are a source of VEGF. We observed that isolated blood neutrophils released VEGF in response to different stimuli and we demonstrated by immunohistochemistry that neutrophils infiltrating inflamed tissues contain VEGF. These results indicate that neutrophil-derived VEGF may be instrumental in regulating vascular responses during acute and chronic inflammation.     

A technique for the fast calculation of three-dimensional photon dose distributions using the superposition model

Techniques for reducing computation time in 3D photon dose calculations are addressed with specific emphasis given to the convolution/superposition approach. A single polyenergetic superposition model calculating absorbed dose per incident photon fluence (Gy cm2) was developed in terms of TERMA and a total energy deposition kernel (a total point spread function). A novel approach was devised for reducing calculation time. The method, named the CF method, was based on the use of a conventional, fast model (here a modified power-law method was used) for the generation of 3D dose distributions on a fine dose matrix. Superposition calculations were carried out on a coarse matrix and calculation speed was increased simply by reducing the number of calculations. A set of correction factors was derived on the coarse grid from the ratio of the dose values from superposition to those from the conventional algorithm. These were interpolated onto the fine matrix and used to modify the dose calculation from the conventional algorithm. The method was tested in a worst-case example where large dose gradients were present and in a clinically relevant irradiation geometry. It is shown that the time required for the generation of a 3D matrix with superposition can be reduced by at least a factor of 100 with no significant loss in accuracy.     

Smoking among males in a low socioeconomic area of Karachi

Approximately half of the families in Pakistan reported having at least one smoker in 1992. Smokers were less educated, poorer and more likely to come from a rural background than non-smokers. The proportion of family earnings in poor families with marginal incomes, may be substantial. We conducted this survey to determine the prevalence of cigarette smoking in males over 15 years of age in Azam Basti, an urban squatter settlement of Karachi where 31% of the children less than 5 years old were malnourished. A pretested, structured questionnaire was administered to males aged fifteen years and above, from randomly selected homes in Azam Basti. In our sample of 102 persons the respondents were 38 years old on average, and earned about Rs. 4,500 (US $130) per month. Persons with 10 or more years of education were thrice as likely to have never smoked as compared to those with less than ten years of schooling, (OR = 3.6, 95% confidence interval 1.2, 11.4). Current smokers were more than twice as likely as non-smokers to have monthly household incomes less than Rs. 5000 (US $140) (OR = 2.4, 95% confidence interval 0.8, 7.3). Smoking is common in urban squatter settlements in Pakistan. Parental smoking and its relationship with malnutrition in children under five is not well documented or publicized, even though there is evidence that it has a contribution. We propose that primary health care programs consider smoking prevention and cessation as community based interventions.