Radiographic features of periodontal bone defects: evaluation of digitized images.

OBJECTIVES: Radiographic evaluation of periodontal conditions is a difficult process because of the many limitations inherent to this complementary examination and the lack of image specificity for different types of bone defects. The objectives of this study are to utilize digitized imaging resources to describe the radiographic features of different types of periodontal bone defects produced artificially in dry mandibles. METHODS: 14 dry mandibles were utilized, in which periodontal bone defects were produced. Digital photographs and conventional radiographs of each site were obtained in a standardized manner, before and after producing these defects. The radiographs were then digitized, displayed on the screen and evaluated by three examiners. RESULTS: Most of the bone defects presented distinct imaging characteristics that allowed them to be identified, with the exception of one-, two- and three-wall infrabony defects. The defects that were most easily interpreted were horizontal and vertical defects and the most difficult were defects in the radicular septum. CONCLUSIONS: Despite the importance of imaging diagnoses in reaching clinical decisions regarding treatment, such diagnoses for different types of periodontal bone defects are extremely difficult to make. In the present study, the utilization of digital tools for interpreting digitized radiographic images facilitated the process.

Spatial distribution of the Human T-Lymphotropic Virus types I and II (HTLV-I/II) infection among blood donors of Hemominas Foundation, Belo Horizonte, Minas Gerais State, Brazil, 1994-1996.

We conducted a cross-sectional study of the spatial distribution of HTLV-I/II infection among blood donors of Hemominas Foundation, living in Belo Horizonte, from 1994 to 1996. Study population (1,022) was composed by 533 cases (positive Western Blot (WB), indeterminate WB and ELISA positive without WB result) and a random sample of 489 non-cases (HTLV-I/II serum negative). Cases and non-cases were georeferenced using the exact or an approximation of the household address reported at the blood donation interview. Using multivariate analysis, cases with WB result are less likely to be reposition blood donors compared to voluntary ones (OR = 0.70; CI 95%: 0.50-0.99). Using the difference between univariate K functions, we found no evidence that cases and non-cases differ in their spatial distribution. We found no evidence that cases with and without WB result differ in the distance between their residence and Hemominas Foundation. No donors without WB result were georeferenced by the exact address. These donors could not have received the Hemominas letter inviting them to return to collect the second blood sample.

Novel microbial lipases: catalytic activity in reactions in organic media.

2,000 microbial strains were isolated from soil samples and tested to determine their lipolytic activity by employing screening techniques on solid and in liquid media. Culture broths were initially tested with 1,2-O-dilauryl-rac-glycero-3-glutaric acid-resorufinyl ester, a chromogenic substrate specific for lipases. Fourteen lipase-producing microorganisms were selected and their taxonomic identification was carried out. Hydrolysis of tributyrin or olive oil and the esterification of oleic acid with heptanol were selected to preliminary evaluate the catalytic activity of these lipases. All the selected lipases catalysed this esterification reaction with good yields. Resolution of (R,S)-2-(4-isobutylphenyl) propionic acid, (R,S)-1-phenylethanol, (R,S) 1-phenylethylamine and of (R) or (S) glycidol were performed to evaluate the stereoselectivity of these novel enzymes as biocatalysts in reactions in organic media. Lipases from the fungi Fusarium oxysporum and Ovadendron sulphureo-ochraceum gave the best yields and enantioselectivities in the resolution of racemic ibuprofen and 1-phenylethanol. Several lipases displayed a high stereoselectivity in the resolution of chiral amines by an alcoxycarbonylation reaction.

Ethical issues in a Brazilian hospital.

PURPOSE: The objective of this paper is to discuss ethical issues such as data protection, confidentiality, and patient freedom taking two ongoing studies as examples. METHODS: The two studies are being carried out at a public hospital in southern Brazil. Study 1 evaluates inadequate use of drugs (mainly vancomycin) and aims at reviewing criteria for drug use control. It includes records of 100 patients whose prescriptions are dispensed at the hospital's pharmacy. A major ethical concern in this study was to ensure data confidentiality. Study 2 evaluates treatment adherence by hypertension patients with a focus on hydrochlorothiazide. Here, in addition to data protection, a major ethical concern was the ability of patients to understand the informed consent form and therefore freely enter or refuse to enter the study. Both projects were approved by the Institutional Review Board at Hospital de Clínicas de Porto Alegre. RESULTS: In both studies, data confidentiality is ensured by the removal of all personal information from the forms used for data analysis. In Study 2, readability of the informed consent was considered adequate by the IRB for the population served by the clinic, and one-third of the patients who were contacted agreed to participate in the study. CONCLUSIONS: To obtain reliable results, basic ethical principles must be observed throughout the planning and execution of research projects, whether data are obtained from medical records or from actual interaction with patients. Thus, monitoring by an Institutional Review Board or equivalent is of paramount importance.

Evidence of inappropriate use of vancomycin in a university affiliated hospital in Brazil.

OBJECTIVE: To evaluate the appropriateness of use of vancomycin in a University affiliated Hospital in Brazil. METHODS: One hundred sequential therapeutic courses of vancomycin were retrospectively examined through a chart review. The prescriptions were evaluated in terms of indication, use of critical process indicators, and use of outcome measurements according to an adapted version of the criteria recommended by the American Society of Health-System Pharmacists. RESULTS: The indication for use was appropriate in 39% of the cases. Critical process indicators indicated frequent inappropriate use, mainly in relation to a low frequency of bacterial cultures (54%), infrequent determination of creatinine levels prior to therapy (57%), incorrect dosage (42%), incorrect duration of therapy (63%), and infrequent determination of serum levels of vancomycin (73%). It was impossible to evaluate outcome measurements, since data were not collected in most patients. Larger discrepancies between recommendation and practice were detected in Paediatrics and Paediatric Pneumology Services. CONCLUSION: The misuse of vancomycin in our hospital is very common according to standard guidelines, demanding new policies of control in order to diminish the possibility of the emergence of multi-resistant strains.