Human urine certified reference material CZ 6010: creatinine and toluene metabolites (hippuric acid and o-cresol) and a benzene metabolite (phenol)

A reference material for the biological monitoring of occupational exposure to toluene, benzene and phenol was prepared. O-cresol and hippuric acid (metabolites of toluene) are used for the biological monitoring of occupational exposure to toluene. Phenol, a metabolite of benzene, is used for the biological monitoring of exposure to benzene, but phenol can of course also be used as an indicator of exposure to phenol as well. The reference material (RM) used for the determination of these metabolites was prepared by freeze-drying pooled urine samples obtained from healthy persons occupationally exposed to toluene and those taking part in an inhalation experiment. Tests for homogeneity and stability were performed by determining urine concentrations of o-cresol, hippuric acid, creatinine and phenol. To investigate the stability of the RM, the urinary concentrations of o-cresol and phenol were monitored for eighteen months using GC and HPLC, while those of hippuric acid and creatinine were followed for five and six years, respectively, using HPLC. Analysis of variance showed that the concentrations did not change. The certified concentration values (and their uncertainties) of the substances in this reference material (phenol concentration c=6.46+/-0.58 mg l(-1); o-cresol concentration c=1.17+/-0.15 mg l(-1); hippuric acid concentration c=1328+/-30 mg l(-1); creatinine concentration c=0.82+/-0.10 g l(-1)) were evaluated via the interactive statistical programme IPECA.

Influence of intraocular lens material on the development of acute endophthalmitis after cataract surgery?

PurposeTo investigate the causal relationship between acute postoperative endophthalmitis (POE) after cataract surgery and the biomaterial properties of the intraocular lens (IOLs) implanted.MethodsThis retrospective cohort study included all patients who had undergone cataract surgery with IOL implantation at the Lyon Croix-Rousse University Hospital between 1st January 1994 and 31st December 2004. Details respecting the type of IOL implanted (material and manufacturer) were meticulously recorded. The number of patients presenting with POE within 6 weeks of cataract surgery was documented together with their medical characteristics. These data were then compared, and Fisher's exact test was used to establish the significance of any apparent associations.ResultsEight of the 5837 eyes manifested acute POE (0.14%). Seven of these were composed of polymethylmethacrylate (PMMA) and one of heparinized PMMA. Patients with PMMA IOLs carried a higher risk of developing POE than did those implanted with either heparinized PMMA (P=0.001), hydrophilic acrylic, or hydrophobic acrylic IOLs (P=0.002).ConclusionsThe incidence of acute POE after cataract surgery in our hospital is similar to that currently reported for other institutions in developed countries. Our results add further evidence that IOL material and type are factors contributing to the risk to develop an acute POE after cataract surgery, and that PMMA IOLs may be associated with an increased risk of POE.Eye advance online publication, 15 September 2006; doi:10.1038/sj.eye.6702544.

Maxillary sinus floor elevation using the (transalveolar) osteotome technique with or without grafting material. Part I: Implant survival and patients' perception

OBJECTIVES: To analyze the survival and success rates of implants installed utilizing the (transalveolar) osteotome technique, to compare peri-implant soft tissue parameters and marginal bone levels of osteotome-installed implants with implants placed using standard surgical procedures, and to evaluate patient-centered outcomes. MATERIAL AND METHODS: During 2000 to 2005, 252 Straumann dental implants were inserted in 181 patients. The surgical technique was a modification of the original osteotome technique presented by Summers. In addition to the clinical examination, the patients were asked to give their perception of the surgical procedure, utilizing a visual analogue scale. RESULTS: The cumulative survival rate of the osteotome-installed implants after a mean follow-up time of 3.2 years, was 97.4% (95% confidence intervals: 94.4-98.8%). From the 252 implants inserted, three were lost before loading and another three were lost in the first and second year. According to residual bone height the survival was 91.3% for implant sites with < or =4 mm residual bone height, and 90% for sites with 4 mm and 5 mm, when compared with that of 100% in sites with bone height of above 5 mm. According to implant length the survival rates were 100% for 12 mm, 98.7% for 10 mm, 98.7% for 8 mm and only 47.6% for 6 mm implants. Soft tissue parameters (pocket probing depth, probing attachment level, bleeding on probing and marginal bone levels) did not yield any differences between the osteotome-installed and the conventionally placed implants. More than 90% of the patients were satisfied with the implant therapy and would undergo similar therapy again if necessary. The cost associated with implant therapy was considered to be justified. CONCLUSION: In conclusion, the osteotome technique was a reliable method for implant insertion in the posterior maxilla, especially at sites with 5 mm or more of preoperative residual bone height and a relatively flat sinus floor.

Early reherniation of disk material in eleven dogs with surgically treated thoracolumbar intervertebral disk extrusion.

OBJECTIVE To report findings and outcomes of dogs with reherniation of nuclear material within 7 days of hemilaminectomy for acute thoracolumbar (TL) intervertebral disk extrusion. STUDY DESIGN Retrospective case series. ANIMALS Chondrodystrophic dogs (n = 11). METHODS Dogs with acute neurologic decline within 1 week of surgical decompression for TL disk extrusion were identified. Advanced imaging was used to document extradural spinal cord compression at the previous surgery site. Ten dogs had a 2nd decompressive surgery to remove extruded nuclear material. RESULTS All dogs had acute neurologic deterioration (average, 2 neurologic grades) 2-7 days after initial hemilaminectomy. Computed tomography (CT; n = 10) or myelography (n = 1) documented extradural spinal cord compression compatible with extruded disk material at the previous hemilaminectomy site. Dogs that had a 2nd surgical decompression improved neurologically within 24 hours and were paraparetic at discharge. The single dog that did not have decompressive surgery did not regain deep nociception during 185-day follow-up. CONCLUSIONS Early reherniation at the site of previous hemilaminectomy can produce acute deterioration of neurologic function and should be investigated with diagnostic imaging. Repeat decompressive surgery can lead to functional recovery.