The efficacy of a novel antibacterial hydroxyapatite nanoparticle-coated indwelling urinary catheter in preventing biofilm formation and catheter-associated urinary tract infection in rabbits

The aim of this study was to investigate of the efficacy and reliability of a novel antimicrobial hydroxyapatite (HA) nanoparticle coating of urethral catheters, in the prophylaxis of biofilm formation and bacteriuria in rabbits. A total of 60 male rabbits were randomized to the control and study groups and each group was divided into three subgroups depending on 3, 5 and 7 days of the urethral catheterization period. The rabbits in the study group were catheterized with Ag⁺-incorporated nano-HA coated urethral catheters and those in the control group with standard silicon–latex urethral catheters. Urine and catheter surface smear samples were conducted for bacteriological analysis. Catheter cross-section samples were undergone measuring of biofilm thickness. Tissue samples of bladder and urethra were inspected for histological changes. The results indicate that at the end of 7 days of the catheterization period, the number of the rabbits with bacteriuria was significantly lower in the study group versus control group (p ^¶ = 0.020). The biofilm formation on luminal surface of the catheters was significantly thinner in the study group versus control group, at the end of 5 and 7 days of the catheterization period (0.035 and 0.035, respectively).No histological adverse change or particle penetration was detected in the urothelium. In conclusion, it was observed that Ag⁺ + HA nanoparticle coating significantly lowered the incidence of catheter-related bacteriuria and decreased biofilm formation, at the end of 7 days study period. The novel antimicrobial urethral catheter coating appeared to have a potential in the prophylaxis of catheter-induced urinary tract infections.     

Non-Hodgkin's lymphoma of the gastrointestinal tract: an analysis of clinical and pathologic features affecting outcome

Clinical and histopathologic data from 87 patients with primary non-Hodgkin's lymphoma of the gastrointestinal (GI) tract diagnosed between 1974 and 1984 were reviewed. B-cell lymphomas of intermediate- or high-grade histology constituted 78% of lesions. Stage of disease varied with histologic grade, with a preponderance of advanced disease (stages IIIE and IV) in patients with low-grade lymphoma (15 of 21) (71%), compared with higher grade lesions (38%, P = .01). Among patients with nonlocalized (stages IIE through IV) lymphoma of intermediate- or high-grade histology, surgical resection of the primary focus afforded a higher rate of complete remission (CR) (70% v 50%) and sustained CR (61% v 21%, P = .04) after cytotoxic therapy compared with the nonresected cohort. The median survival in the resected group was 51 months + compared with 13 months in the nonresected patients (P = .012). Differences in outcome were attributable to a high risk of treatment-related complications (perforation and/or hemorrhage) (43% v 0%, P = .001) and local relapse (29% v 4%, P = .05) in nonresected individuals. Life-threatening local complications were not observed in patients with low-grade lymphoma managed solely with medical therapy. Histologic findings from surgically staged patients identified presence of extravisceral disease and intermediate- or high-grade tumor histology as features predictive of transmural invasion, enabling potential identification of patients who might be optimally managed by resection of the primary GI focus before initiation of cytotoxic therapy.     

Trimethoprim interferes with serum methotrexate assay by the competitive protein binding technique

Administration of Bactrim (a combination of trimethoprim and sulfamethoxazole) to a patient who also was receiving methotrexate caused a significant increase in apparent plasma methotrexate concentrations as determined by competitive protein binding assay with use of dihydrofolate reductase (EC 1.5.1.3) from Lactobacillus casei as the binding protein. This spurious increase was caused by trimethoprim in the patient's plasma. A plasma trimethoprim concentration of 0.1 mg/L inhibited binding of radiolabeled methotrexate to dihydrofolate reductase by 50%. In contrast, radioimmunoassay for methotrexate was not affected by concomitant administration of trimethoprim. The competitive protein binding assay for methotrexate should not be used in patients being treated with Bactrim or Septra (a similar combination). However, the L. casei competitive protein binding assay technique can be used to assay plasma trimethoprim concentrations with sensitivity to 0.02 mg of trimethoprim per liter.     

Rhabdomyolysis-induced acute renal failure associated with legionnaires' disease

Legionnaires' disease (LD) is a systemic infectious disease primarily involving the lungs. Rhabdomyolysis, with subsequent acute renal failure, is an infrequently recognized entity associated with high mortality rates in LD patients. As in the case presented herein, initial respiratory signs and symptoms may not be prominent. Early diagnosis and appropriate treatment can be life-saving.