Human cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis in Santiago del Estero, Argentina: identification of parasites by monoclonal antibodies and isoenzymes

Bacteroides forsythus is a fastidious anaerobic Gram-negative organism associated with active periodontal disease. The ability of random amplified polymorphic DNA (RAPD) fingerprinting to generate species-specific markers was exploited towards the construction of a polymerase chain reaction (PCR)-DNA probe assay specific for B. forsythus. The strategy included the four following steps: (1) construction of a first generation DNA probe based on a 507-bp RAPD species-specific marker; (2) cloning and sequencing the 507-bp RAPD marker; (3) design of the primer pair Bf 392-1/Bf 392-2 flanking a 392-bp specific internal sequence; and (4) synthesis of quantities of a 392-bp second generation DNA probe by PCR amplification. The PCR-DNA probe assay includes a PCR amplification of a 392-bp specific sequence in the genomic DNA of B. forsythus strains followed by hybridization with the 392-bp digoxigenin-labelled second generation probe. We observed strong, specific hybridization with the amplified DNAs from 11 stains of B. forsythus and no cross-hybridization with the PCR products from 22 foreign species. The PCR-DNA probe assay must be seen as a highly specific and sensitive method for the detection of B. forsythus in mixed infections.     

The infected urachal cyst: primary excision versus a staged approach

PURPOSE: We compared outcomes following single or 2-stage repair of infected urachal cysts in the pediatric population. MATERIALS AND METHODS: We reviewed the records of 17 patients 1 day to 14 years old (median age 22 months) with a urachal cyst. Immediate cyst excision was performed in 6 patients without infection, while those with an abscess underwent single or 2-stage repair. RESULTS: Median postoperative hospital stay for the urachal abscess group was 14 and 11.5 days for single and 2-stage procedures, respectively. After immediate excision postoperative complications developed in each case, although none occurred with a 2-stage approach. CONCLUSIONS: In the absence of infection, urachal cyst excision affords the most benign postoperative course. However, when infection is present, perioperative drainage with subsequent total excision, including a cuff of bladder, may offer the most effective surgical option.     

Molecular cloning of murine CC CKR-4 and high affinity binding of chemokines to murine and human CC CKR-4

We have cloned the murine homologue of human CC Chemokine Receptor-4 (CC CKR-4). In equilibrium competition binding assays performed in undifferentiated HL-60 cells transfected with human and murine CC CKR-4 cDNA, the IC50 values for the binding of [125I]macrophage inflammatory protein-1 alpha to human and murine CC CKR-4 were 14.5 +/- 9.0 nM and 10.1 +/- 3.0 nM, respectively, and the IC50 values for the binding of [125I]RANTES to human and murine CC CKR-4 were 9.3 +/- 3.0 nM and 5.7 +/- 2.6 nM, respectively. The cDNA clone for murine CC CKR-4 is 1531 bp, and the largest open reading frame encodes a protein of 360 amino acids that is 85% identical to human CC CKR-4. Murine CC CKR-4 was detected in the thymus and T-cell lines by Northern blot analysis. This first report of direct binding of chemokines to CC CKR-4 demonstrates that the highly homologous human and murine receptors have similar binding characteristics and tissue distribution.     

Experimental studies on the mechanisms of tiaprofenic acid photosensitization

Red blood cell lysis and histidine degradation, photosensitized by tiaprofenic acid (TIA), were investigated. Photohaemolysis was markedly enhanced in oxygenated solutions, but was also intense in the presence of nitrogen. Photohaemolysis was inhibited by butylated hydroxyanisole and reduced glutathione, but was unaffected by sodium azide, superoxide dismutase and mannitol. The TIA-induced photo-oxidation of histidine was greatly enhanced in the presence of oxygen and almost completely inhibited in solutions bubbled with nitrogen. Sodium azide, butylated hydroxyanisole and reduced glutathione inhibited the photodegradation of histidine. Phototoxicity to histidine was unaffected by mannitol and superoxide dismutase. The overall results suggest that molecular mechanisms involving free radicals and singlet oxygen are responsible for TIA-photosensitized reactions. These two in vitro models (photohaemolysis and histidine degradation) represent different mechanisms of phototoxicity, but complement one another in the investigation of potential phototoxic substances.