Contribution of common and recently described respiratory viruses to annual hospitalizations in children in South Africa.

The contribution of viruses to lower respiratory tract disease in sub-Saharan Africa where human immunodeficiency virus may exacerbate respiratory infections is not well defined. No data exist on some of these viruses for Southern Africa. Comprehensive molecular screening may define the role of these viruses as single and co-infections in a population with a high HIV-AIDS burden. To address this, children less than 5 years of age with respiratory infections from 3 public sector hospitals, Pretoria South Africa were screened for 14 respiratory viruses, by PCR over 2 years. Healthy control children from the same region were included. Rhinovirus was identified in 33% of patients, RSV (30.1%), PIV-3 (7.8%), hBoV (6.1%), adenovirus (5.7%), hMPV (4.8%), influenza A (3.4%), coronavirus NL63 (2.1%), and OC43 (1.8%). PIV-1, PIV-2, CoV-229E, -HKU1, and influenza B occurred in <1.5% of patients. Most cases with adenovirus, influenza A, hMPV, hBoV, coronaviruses, and WU virus occurred as co-infections while RSV, PIV-3, and rhinovirus were identified most frequently as the only respiratory pathogen. Rhinovirus but not RSV or PIV-3 was also frequently identified in healthy controls. A higher HIV sero-prevalence was noticed in patients with co-infections although co-infections were not associated with more severe disease. RSV, hPMV, PIV-3, and influenza viruses had defined seasons while rhinovirus, adenovirus, and coronavirus infections occurred year round in this temporal region of sub-Saharan Africa.

Viral etiology of severe pneumonia among Kenyan infants and children.

CONTEXT: Pneumonia is the leading cause of childhood death in sub-Saharan Africa. Comparative estimates of the contribution of causative pathogens to the burden of disease are essential for targeted vaccine development. OBJECTIVE: To determine the viral etiology of severe pneumonia among infants and children at a rural Kenyan hospital using comprehensive and sensitive molecular diagnostic techniques. DESIGN, SETTING, AND PARTICIPANTS: Prospective observational and case-control study during 2007 in a rural Kenyan district hospital. Participants were children aged 1 day to 12 years, residing in a systematically enumerated catchment area, and who either were admitted to Kilifi District Hospital meeting World Health Organization clinical criteria for severe pneumonia or very severe pneumonia; (2) presented with mild upper respiratory tract infection but were not admitted; or (3) were well infants and children attending for immunization. MAIN OUTCOME MEASURES: The presence of respiratory viruses and the odds ratio for admission with severe disease. RESULTS: Of 922 eligible admitted patients, 759 were sampled (82% [median age, 9 months]). One or more respiratory viruses were detected in 425 of the 759 sampled (56% [95% confidence interval {CI}, 52%-60%]). Respiratory syncytial virus (RSV) was detected in 260 participants (34% [95% CI, 31%-38%]) and other respiratory viruses were detected in 219 participants (29%; 95% CI, 26%-32%), the most common being Human coronavirus 229E (n = 51 [6.7%]), influenza type A (n = 44 [5.8%]), Parainfluenza type 3 (n = 29 [3.8%]), Human adenovirus (n = 29 [3.8%]), and Human metapneumovirus (n = 23 [3.0%]). Compared with well control participants, detection of RSV was associated with severe disease (5% [corrected] in control participants; adjusted odds ratio, 6.11 [95% CI, 1.65-22.6]) while collectively, other respiratory viruses were not associated with severe disease (23% in control participants; adjusted odds ratio, 1.27 [95% CI, 0.64-2.52]). CONCLUSION: In a sample of Kenyan infants and children admitted with severe pneumonia to a rural hospital, RSV was the predominant viral pathogen.

The effect of Ge, Si and Sn phthalocyanine photosensitizers on cell proliferation and viability of human oesophageal carcinoma cells.

The photodynamic activity of water soluble mixed sulfonated metallophthalocyanines complexes: GePcSmix, SnPcSmix and SiPcSmix on human oesophageal carcinoma (SNO) cells are reported, and compared with the activity of the unmetallated H2PcSmix and of the newly synthesized water soluble adjacently substituted binaphthalo phthalocyanine (complex 3). The alkaline phosphate (ALP) showed damage to the cell membrane in the presence of complex 3 without irradiation. The GePcSmix complex caused a relatively large increase in inflammation and a high intracellular ATP.

The effects of two metallophthalocyanines on the viability and proliferation of an esophageal cancer cell line.

OBJECTIVE: The objective of this study was to establish the influence of two metallophthalocyanine photosensitizers, in their inactive and activated forms, on the cellular reactions of esophageal cancer cells. BACKGROUND DATA: Photodynamic therapy (PDT) is an alternative used in the treatment of cancer. During PDT, the activated compound produces cytotoxic singlet molecular oxygen ((1)O(2)), which ultimately leads to cell death. Esophageal cancer has become one of the most common cancers to occur in the world, and the incidence in South Africa is high, especially within the black male population. METHODS: Optimal photosensitizer concentration was determined by following the viability of esophageal cancer (SNO) cells treated with a range of concentrations of two metallophthalocyanine photosensitizers, GePcSmix and AlPcSmix, activated by irradiation at a fluence of 20 J/cm(2). Changes in cell morphology were observed after treatment with optimal photosensitizer concentrations, and the effect of the treatment on cell proliferation and cytotoxicity were studied. RESULTS: Cell viability decreased in a dose-dependent manner after PDT, while the photosensitizers in their inactive forms did not have an effect on the cells. The altered morphology of cells after PDT was indicative of a necrotic mode of cell death. The optimal photosensitizer concentrations reduced cell proliferation by more than 50% and a significant reduction in cytotoxicity, as detected by lactate dehydrogenase release, was observed following PDT. CONCLUSION: Under the studied parameters PDT using GePcSmix and AlPcSmix in vitro could be a useful therapy for esophageal cancer since the photosensitizers alone caused no damage, but cell death is imminent post-PDT.