Lipid and protein histochemistry of enamel — Effects of fluoride

Summary Staining reactions for a number of histochemical procedures for lipophilic staining and protein were studied in the enamel matrix along the length of rat incisors. Sudan Black gave a positive stain across the whole thickness of very early enamel (up to 30 m) but this staining only continued as a narrow band close to the ameloblasts as the enamel matured. A variety of tests for protein produced almost identical staining patterns in enamel matrix up to 100 m thick. Since the pattern of lipid staining persisted, after using a number of procedures which could normally be expected to remove lipid, it is suggested that Sudan Black positive staining may be due to lipophilic protein rather than lipid itself. Fluoride did not significantly alter the staining reactions for lipid and protein but did proceduce matrix which was much more effectively stained by cross-linking agents FFDNB and FF sulphene.     

Value of P-glycoprotein and clinicopathologic factors as the basis for new treatment strategies in high-grade osteosarcoma of the extremities.

PURPOSE: To evaluate the prognostic value of P-glycoprotein and clinicopathologic parameters in a large series of high-grade osteosarcoma (OS) patients treated at the Rizzoli Institute. PATIENTS AND METHODS: With the use of immunohistochemistry, P-glycoprotein was assessed in 149 patients with primary, nonmetastatic, high-grade OS who were homogeneously treated with chemotherapy protocols based on doxorubicin, high-dose methotrexate, and cisplatin and the addition of ifosfamide in the postoperative phase. RESULTS: P-glycoprotein positivity was found in 47 of 149 cases (32%) and was significantly associated with a higher incidence of relapse and a worse outcome, as was age younger than 12 years and tumor volume greater then 150 mL at diagnosis. Multivariate analysis further confirmed the prognostic value of these parameters, which all were independent adverse prognostic factors. Event-free survival and proportional hazards regression analyses confirmed that overexpression of P-glycoprotein at clinical onset is the most important adverse prognostic factor for high-grade OS patients treated with these chemotherapy protocols. CONCLUSION: Increased P-glycoprotein levels, together with tumor volume and age, should be taken into consideration to identify, at time of diagnosis, subgroups of OS patients with a higher risk of recurrence. This subgroup identification will constitute the basis for drawing individualized treatment protocols on the basis of risk evaluation, with the aim of using more aggressive chemotherapy, or combination chemotherapy with other adjuvants, only in those patients for which more aggressive regimens are strictly necessary and warranted.     

Quality improvement in immunization delivery following an unsuccessful immunization recall.

OBJECTIVES: Within a clinic serving disadvantaged children, 1) to evaluate a multifaceted quality improvement (QI) project to improve immunization (IZ) up-to-date (UTD) rates and 2) to assess the efficacy of IZ reminder/recall performed following QI. METHODS: A year-long QI project followed by a trial of reminder/recall. QI interventions were targeted at previously identified barriers to IZ and were designed specifically to improve the efficacy of reminder/recall. QI interventions were designed to 1) increase the use of medical record releases to document IZs received elsewhere; 2) improve the accuracy of parental contact information; and 3) reduce missed opportunities by utilizing chart prompts, provider education, and provider reminders. Following QI, we conducted a randomized trial of reminder/recall. RESULTS: UTD rates for 7-11 month olds increased from 21% before the QI project to 52% after (P <.0001); rates for 12-18 month olds increased from 16% before QI to 44% after (P <.0001); 19-25 month olds 18% before to 33% after (P <.001). After QI, an average of 61 records per month were updated with IZs received elsewhere. However, the accuracy of parental contact information worsened (29% unreachable before QI vs 44% after, P <.001) and missed opportunities did not improve (8% before vs 6% after, P = not significant [NS]). A subsequent trial of reminder/recall did not increase UTD rates, with 17% of recalled children brought UTD vs 16% of controls (P = NS). CONCLUSIONS: Clinic-based QI increased documented UTD rates in a disadvantaged patient population. However, IZ reminder/recall did not further increase UTD rates above the rates achieved by the QI process.     

Mortality after aortic valve replacement: results from a nationally representative database

Background. Nationally representative estimates of in-hospital mortality after aortic valve replacement are needed to evaluate whether results from The Society of Thoracic Surgeons National Cardiac Surgery Database are applicable to other institutions in the United States performing these procedures.

Methods. Data from the 1994 Nationwide Inpatient Sample were used to estimate the patient characteristics and in-hospital mortality rates associated with aortic valve replacements performed in nonfederal hospitals in the United States. Procedural and hospital characteristics were examined for possible associations with in-hospital mortality.

Results. An estimated 46,397 aortic valve replacements were performed. In-hospital mortality occurred in 4.3% of first-time isolated aortic valve replacements and 6.4% overall. The highest quartile of procedure-specific hospital volume, compared with the lowest quartile, was associated with lower in-hospital mortality (adjusted odds ratio, 0.58; 95% confidence interval, 0.42 to 0.81).

Conclusions. The in-hospital mortality rates observed in this study are very similar to those reported from The Society of Thoracic Surgeons database. These data provide substantial evidence that results from The Society of Thoracic Surgeons database are representative of those achieved at other institutions. However, procedure-specific hospital volume must be considered in applying these results to individual institutions.     

The influence of children's self-report trait anxiety and depression on visual search for emotional faces

BACKGROUND: This study presents two experiments that investigated the relationship between 7- and 10-year-olds' levels of self-report trait anxiety and depression and their visual search for threatening (angry faces) and non-threatening (happy and neutral faces) stimuli. METHOD: In both experiments a visual search paradigm was used to measure participants' reaction times to detect the presence or absence of angry, happy or neutral schematic faces (Experiment 1) or cartoon drawings (Experiment 2). On target present trials, a target face was displayed alongside three, five or seven distractor items. On target absent trials all items were distractors. RESULTS: Both experiments demonstrated that on target absent (but not present) trials, increased levels of anxiety produced significantly faster search times in the angry face condition, but not in the neutral condition. In Experiment 2 there was some trend towards significance between anxiety and searches for happy faces in absent trials. There were no effects of depression on search times in any condition. CONCLUSION: The results support previous work highlighting a specific link between anxiety and attention to threat in childhood.     

HCV seroconversion among never-injecting heroin users at baseline: No predictors identified other than starting injection

BACKGROUND: Heroin users who do not inject constitute a large pool of drug users with a potentially important impact on public health. We aimed to estimate the incidence of hepatitis C virus (HCV) among heroin users who had never injected (NIDUS) at baseline, and the effect of starting injecting during follow-up, other percutaneous exposures, sharing snorting paraphernalia, cocaine/crack use, and risky sexual behaviour on HCV-seroconversion. METHODS: Prospective cohort of 305 HCV-negative NIDUs at baseline, aged 18-30 and street-recruited in three Spanish cities in 2001-2003. Computer-assisted personal interviews were conducted and dried blood-spot samples were collected. Bivariate and multivariable Poisson models were used. RESULTS: Among the 305 never-injectors who were HCV-negative at baseline, 197 (64.6%) were followed-up and 21 seroconverted [HCV-incidence rate=5.8/100 person-years at risk (pyar) (95% CI: 3.6-8.9)]. HCV incidence in new-injectors was 28.4/100pyar [(95% CI, 14.7-49.7) vs. 2.8/100pyar (95% CI, 1.3-5.4)] among NIDUs. Of the risk exposures considered, starting injecting was the only predictor of HCV-seroconversion [adjusted relative risk=10.1, 95% CI: 3.8-26.7]. CONCLUSION: The HCV-seroconversion rate was 10 times higher among new-injectors than never-injectors. No predictors other than starting injecting were found for HCV-seroconversion. Harm reduction interventions to prevent HCV infection should include prevention of drug injection.