Pediatric pulmonology
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Pediatric pulmonology · Dec 2003
Review Comparative StudyImpact of HIV on childhood respiratory illness: differences between developing and developed countries.
The main differences of the impact of HIV on childhood respiratory illness between developed and developing countries, and particularly some countries in Africa, are the scale of the problem and the lack of resources to address problems of prevention, diagnosis, and management. Recent data from HIV-infected African children are reviewed and show that the pattern of respiratory disease in these children is not markedly different to the pattern that was reported from the USA and Europe prior to the use of antiretroviral therapy and routine Pneumocystis jiroveci pneumonia (PCP) prophylaxis for HIV-exposed infants. Bacterial pneumonia is very common in all age groups. ⋯ One difference is that pulmonary tuberculosis (PTB) is relatively more common in HIV-infected African children. This is likely to reflect the higher prevalence of smear-positive PTB in the region and therefore of exposure/infection compared to developed countries. Autopsy studies have provided a lot of useful data, but more prospective clinical and intervention studies from different parts of the region are needed in order to improve clinical diagnosis and management.
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Pediatric pulmonology · Dec 2003
Comparative StudyProduction of TNF-alpha by polymorphonuclear leukocytes during mechanical ventilation in the surfactant-depleted rabbit lung.
Previous studies showed that the production of tumor necrosis factor-alpha (TNF-alpha) and the number of recovered cells were much higher in the conventional mechanical ventilation (CMV) group than in the high-frequency oscillation (HFO) group at the end of mechanical ventilation in this model. But the type of cells that generated TNF-alpha in the lungs remained unclear. It was shown that the alveolar macrophage was the source of TNF-alpha in the early stage, but that in the later stage, the cells in the lung lavage fluid contained almost no macrophages. ⋯ The level of TNF-alpha was significantly greater in the CMV group after ventilation (P < 0.05). We performed RT-PCR analysis, in which we showed the presence of TNF-alpha mRNA in the intraalveolar cells (PMN) after 4 hr of CMV, and then demonstrated a positive immunofluorescence reaction to anti-TNF-alpha antibody in PMN separated from the lavage fluid. Our conclusion is that in this surfactant-depleted lung model, PMN is one of the sources of TNF-alpha in the lavage fluid after 4 hr of CMV.