Evaluation of a non-name-based HIV reporting system in San Francisco

OBJECTIVE: To develop and evaluate a non-name-based HIV reporting system. METHODS: A population-based study of the accuracy of a set of non-name codes and a prospective study of a laboratory-initiated HIV surveillance system conducted at a county hospital (site 1) and a health maintenance organization (site 2). Participants were persons reported with AIDS in San Francisco and patients with a positive test result for HIV antibody, p24 antigen, viral load, or a CD4 count at the study sites. RESULTS: Proper match rate was 95% for records with complete codes and records with at least 50% of the codes. Proper non-match rate was 99% for records with all code elements and 96% for records with at least 50% of the elements. Completeness of reporting was 89% (site 1) and 87% (site 2). Median number of days between test and receipt of test report at the health department was 9 days at site 1 and 7 days at site 2. During 1999, 78% of HIV-infected patients at site 1 and 87% at site 2 had an HIV-specific laboratory test. CONCLUSIONS: A non-name-based laboratory reporting system for HIV is feasible.     

Preparation of epoxy-SiO2 hybrid sol-gel material for bone cement

An organic-inorganic hybrid material, epoxy-SiO(2), was prepared by incorporating epoxy structure units covalently into a SiO(2) glass network via the sol-gel approach. The precursor was obtained by the reaction of diglycidyl ether of bisphenol A (DGEBA) with 3-aminopropyl trimethoxysilane (APTS). The precursor was then hydrolyzed and co-condensated with tetraethyl orthosilicate (TEOS) in tetrahydrofuran (THF) at room temperature to yield epoxy-SiO(2) hybrid sol-gel material having a 50 wt % SiO(2) content. Thermal properties of the hybrid material were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The hybrid sol-gel material epoxy-SiO(2) was the solid, powder component of bone cement. The liquid component contains bis-phenol-A glycidyl methacrylate (Bis-GMA), triethyleneglycol dimethacrylate (TEGDMA), and methyl methacrylate (MMA) with 25, 55, and 20 vol %, respectively. We discuss the comparison between the new epoxy-SiO(2) bone cement and the commercial Simplex P bone cement. Mechanical properties such as Young's modulus, compressive strength, hardness, and impact strength of the new epoxy-SiO(2) bone cement exceeded those of Simplex P bone cement. The tensile and bending strengths of the new epoxy-SiO(2) bone cement were approximately the same as those of Simplex P bone cement. In order to evaluate the biocompatibility of the new bone cement, an MTT test and optical microscopy were conducted in cell culture. Results indicated that the new epoxy-SiO(2) bone cement exhibits very low cytotoxicity compared with Simplex P bone cement.     

In vivo acquisition of ceftriaxone resistance in Salmonella enterica serotype anatum

The emergence of resistance to antimicrobial agents within the salmonellas is a worldwide and severe problem. A case of treatment failure due to the emergence of resistance to ceftriaxone in Salmonella enterica serotype Anatum was studied. S. enterica serotype Anatum and Escherichia coli, both of which are susceptible to ceftriaxone, were initially isolated from a diabetic patient hospitalized for the treatment of wound and urinary tract infections. Resistant S. enterica serotype Anatum and E. coli strains were isolated concomitantly 2 weeks after the initiation of ceftriaxone therapy. The patient eventually died of a sepsis caused by the ceftriaxone-resistant salmonella. PCR, nucleotide sequence analysis, and DNA-DNA hybridization identified a bla(CTX-M-3) gene located on a 95.1-kb plasmid from the ceftriaxone-resistant isolates of S. enterica serotype Anatum and E. coli. The plasmid was proved to be conjugative. Molecular fingerprinting showed that the susceptible and resistant strains were genetically indistinguishable. The emergence of resistance to ceftriaxone in S. enterica serotype Anatum was due to the in vivo acquisition of a plasmid containing the bla(CTX-M-3) gene and was the cause for treatment failure in this patient.     

Differential persistence among genomovars of the Burkholderia cepacia complex in a murine model of pulmonary infection

Cystic fibrosis patients infected with strains from different genomovars of the Burkholderia cepacia complex can experience diverse clinical outcomes. To identify genomovar-specific determinants that might be responsible for these differences, we developed a pulmonary model of infection in BALB/c mice. Mice were rendered leukopenic by administration of cyclophosphamide prior to intranasal challenge with 1.6 x 10(4) bacteria. Five of six genomovar II strains persisted at stable numbers in the lungs until day 16 with minimal toxicity, whereas zero of seven genomovar III strains persisted but resulted in variable toxicity. We have developed a chronic pulmonary model of B. cepacia infection which reveals differences among genomovars in terms of clinical infection outcome.     

Restorative management of the worn dentition: 2. Localized anterior toothwear

This is the second paper in a four-part series detailing the relative merits of the treatment strategies, clinical techniques and dental materials for the restoration of health, function and aesthetics for the dentition. In this paper the management of wear in the anterior dentition is discussed, using three case studies as illustration.     

Restorative management of the worn dentition: 3. Localized posterior toothwear

In the management of localized posterior occlusal toothwear, care must be taken not only in determining whether the worn teeth are restorable, but also the desirable occlusal scheme. Assessments of the periodontal, endodontic, and coronal tooth tissues, and the occlusal relationship are necessary for a comprehensive treatment plan for worn posterior teeth.