[Bilharziasis--problem disease in developing countries].

2,4-Dichlorophenol (2,4-DCP) degrading mixed culture was immobilized in polyvinyl alcohol jel beads and supplemented to sequencing batch reactors (SBR) to treat 2,4-DCP containing wastewater. Impacts of bioaugmentation level on the performance of bioaugmented systems were studied. Results show that inoculum size affected the start-up time of the SBR systems. For the non-augmented SBR system, nine days was needed for the system to start-up, whereas it only took six, four, three and two days for the SBRs with 1.9%, 3.7%, 5.6% and 9.3% immobilized culture, respectively. In addition, bioaugmented SBR systems demonstrated stronger capacity to cope with high 2,4-DCP shock loading than the control system. The control SBR failed to treat 2,4-DCP at 166 mg/l in influent, while the SBR with 1.9% inoculation could successfully cope with 2,4-DCP at 166 mg/l, but failed at 250 mg/l, and the SBR with 3.7%, 5.6% and 9.3% immobilized culture could successfully degrade 250 mg/l 2,4-DCP in feed. Furthermore, the contributions to the removal of 2,4-DCP by the introduced and indigenous culture in an augmented SBR system at various operation stages were investigated. It was found that augmented culture played the primary role in degrading 2,4-DCP at the beginning of system start-up, but after one-month operation, both the indigenous and the introduced culture posed strong ability to degrade 2,4-DCP.

Anthelmintics↗

PubMed2003

Schistosomiasis and the kidney.

Schistosomiasis is a parasitic infection that affects 200 million people and is directly responsible for an annual death of 20,000 patients. Three species are responsible for most of the morbidity in humans: Schistosoma hematobium in Africa, S. mansoni in Africa and South America, and S. Japonicum in the Far East. Renal involvement occurs mostly with S. hematobium infection as a consequence of fibrosis and calcification of tissue-trapped ova in the lower urinary tract, leading to obstruction, reflux, infection, and stone formation. The resulting interstitial nephritis may present with tubular dysfunction syndrome before it progresses to end-stage renal disease. The bladder lesions also are precancerous. Immune complexes containing S. hematobium or S. mansoni worm antigens may deposit in the glomeruli leading to 5 classes of glomerulonephritis: mesangioproliferative; exudative; mesangiocapillary (membranoproliferative); focal segmental sclerosis; and amyloidosis. Exudative lesions occur in the presence of Salmonella coinfection. Membranoproliferative and focal segmental sclerosis correlate with the degree of associated schistosomal hepatic fibrosis, with immunoglobulin (Ig) A playing a major role in their pathogenesis. Amyloidosis occurs in prolonged infection and correlates with the antigen load. Although the acute and early chronic lesions regress under antiparasitic treatment (eg, praziquantel), chronic sequelae are irreversible. End-stage renal disease obviously requires dialysis and transplantation.

Anthelmintics↗