Computer-aided dermoscopy for diagnosis of melanoma

Background

Recently, it has been observed that Video Display Terminals (VDTs) usage for long periods can cause some dermatological manifestations on the face. An analytical cross-sectional study was designed in order to determine this relationship.

Methods

In this study, 600 office workers were chosen randomly from an organization in Tehran (Iran). The subjects were then divided into two groups based on their exposure to VDTs. 306 workers were considered exposure negative (non VDT user) who worked less than 7 hours a week with VDTs. The remainders 294 were exposure-positive, who worked 7 hours or more with VDTs. The frequency of dermatologic manifestations was compared in these two groups.

Results

In the exposure-positive and exposure-negative groups, the frequency of these dermatologic manifestations were 27 and 5 respectively. After statistical analysis, a P.value of < 0.05 was obtained indicating a statistically significant difference between these two groups for dermatological manifestations.

Conclusion

According to our study, there is a relationship between dermatologic manifestations on the face and exposure to VDTs.     

Beta-blocker use is associated with improved outcomes in adult burn patients

BACKGROUND: There is no direct evidence that beta-blockers improve mortality in burn victims. Beta-blockers attenuate hypermetabolic states in burned children, and perioperative use in elective adult cases has beneficial effects, which suggests that beta-blockers may also improve burn outcomes. However, beta-blockers decrease cardiac output and may decrease oxygen delivery, and theoretically may increase mortality. What is the effect of beta-blockers on healing time and mortality in burn patients? METHODS: This was a retrospective cohort study. We identified three cohorts of adult burn patients between 1996 and 2001: all who were on beta-blockers (BB) before their injury (PMH BB); all who were initiated on BB during their hospitalization for management of hypertension or tachyarrhythmia (HOSP BB); and control, who were never treated with beta-blockers. For each patient in the PMH BB and HOSP BB groups, two patients were placed in the control cohort by matching age and total body surface area burn. Premorbid conditions such as diabetes, hypertension, cardiac disease, renal insufficiency, and diuretic and calcium channel blocker use were analyzed. Multivariate regression models were used to identify independent modifiers. RESULTS: There were 21 PMH BB, 22 HOSP BB, and 86 control patients. All PMH BB patients remained on their BB regimen in the hospital. HOSP BB patients were initiated on beta-blockers at a mean of 8.8 days postinjury. There were no differences in age (mean, 58 +/- 17 years), total body surface area burned (mean, 14 +/- 12%), or mechanism of injury among the cohorts. The mortality rate was 5% for the PMH BB cohort, 27% for the HOSP BB cohort, and 13% for controls. The mean healing times were 51 +/- 29 days for PMH BB patients, 79 +/- 54 days for HOSP BB patients, and 60 +/- 39 for controls. In multivariate analyses, PMH BB was associated with a significant decrease in fatal outcome and healing time (p < or = 0.05 compared with control). CONCLUSION: Beta-blockers have the potential to improve adult burn outcomes. Postinjury treatment should be studied in a randomized, clinical trial.     

Delayed repair for blunt thoracic aortic injury: is it really equivalent to early repair?

BACKGROUND: Blunt thoracic aortic injury (BTAI) is a severe injury that traditionally has mandated immediate surgical repair. Delaying operative intervention for BTAI can allow other life-threatening injuries to be managed first, but potentially increases the risk of aortic rupture and death. The objective of this study was to evaluate the outcome of delayed repair (DR) compared with early repair (ER) for BTAI and to assess the effectiveness of a protocol for medical control of systolic blood pressure and heart rate in those patients whose repairs were delayed. METHODS: This study is a retrospective review of University of Michigan Health System (UMHS) data from January 1, 1992, through March 1, 2003. ER was defined as operative repair within 16 hours from the time of injury. A similar analysis was conducted for patients with BTAI selected from the National Trauma Data Bank. RESULTS: For the UMHS data, there were 45 patients in the DR group and 33 patients in the ER group. Mortality in the ER group versus the DR group was 9% versus 20%. Multivariate analysis adjusting for age, Injury Severity Score, abdominal Abbreviated Injury Scale score, Glasgow Coma Scale score, and intubation status demonstrated an odds ratio for death from ER compared with DR of 1.72 (p = 0.57). Patients undergoing DR had an absolute increase in hospital length of stay (33.1 vs. 20.9 days) and complication rate (2.1 vs. 1.5 incidents per patient). A similar result was obtained for multivariate analysis of the National Trauma Data Bank data, with an odds ratio of 1.40 (p = 0.51) for death from ER versus DR. UMHS patients whose repairs were delayed achieved target systolic blood pressure and heart rate for 76% and 74% of the hourly measurements recorded, respectively. CONCLUSION: Patients with BTAI can safely undergo delayed aortic repair if other injuries warrant a higher treatment priority without increasing their overall risk of mortality. Delayed repair is, however, associated with a higher complication rate.     

The prevalence of antibodies to hepatitis A among preschool children in an urban setting in Turkey

The prevalence of antibodies to hepatitis A virus (HAV) was investigated in 114 children (59.7 per cent males) aged 4-6 years, in the campus area of Middle East Technical University, Ankara, Turkey. The prevalence of hepatitis A antibody in this age group was 11.4 per cent (13/114). The rate of immunized children against hepatitis A was 3.65 per cent (5/137). In conclusion the prevalence of anti-HAV demonstrates the susceptibility of other preschool children to hepatitis A. This may be a cause for considering hepatitis A vaccination before preschool attendance in Turkey.     

A pilot study to predict high cost patients in the pre-operative setting

Introduction: The National Surgical Quality Improvement Program (NSQIP) previously demonstrated that certain clinical variables predict surgical mortality and morbidity. We examined whether these clinical variables could also predict the cost of care in the private sector. Methods: All 1,008 patients enrolled into the NSQIP at our institution between October 2001 and June 2002 were tracked for cost incurred by the health system using our internal cost accounting database. The original data collection of clinical data and outcomes was via a trained nurse reviewer through direct chart review and patient interview. A model for predicting cost was created via multiple linear regression systematically testing 44 preoperative variables against log-transformed cost. This model was then recalculated using the statistically significant variables from the initial model with the inclusion of a variable denoting occurrence of a complication. Testing was also performed to fit the model to only those without post-operative complications as well as those that survived. Results: While 31 variables were significant when tested separately, after considering interaction, a single model was derived from the 15 statistically significant (p < 0.05) preoperative variables predicted 65% of the variation in hospital costs (adjusted R² = 0.650). Top predictors of increased costs included: operation requiring inpatient stay, high ASA classification, low albumin, use of general anesthesia, high surgical complexity, and high BUN. Though complications were significantly correlated with increased costs, including whether complications actually occurred only improved the best overall model’s predictive capability by an additional 2% of the variation in costs for the entire population (adjusted R² = 0.669). Testing the model’s output in the subset of patients that avoided complications yielded an R² of 0.438. Conclusions: High cost patients can be predicted in the preoperative setting. These factors predicted higher costs even cases that did not have complications as viewed after the fact. It may be feasible to create benchmarking studies that “risk-adjust” costs as they relate to specific patient populations, which will allow for comparisons across institutions of cost-effectiveness. Institutions treating higher risk patients should seek increased reimbursement for these populations in order to match costs with revenues.     

Hydrophobic and ionic factors in the binding of local anesthetics to the major variant of human alpha1-acid glycoprotein

Understanding the interaction of local anesthetics (LAs) with plasma proteins is essential to understanding their systemic pharmacology and toxicology. The molecular determinants of LA binding to the major variant (F1*S) of human alpha1-acid glycoprotein (AGP) were therefore investigated spectrofluorometrically using whole AGP and a novel, F1*S variant-selective probe previously developed in our laboratory. Equilibrium- competitive displacement of this probe by LAs, observed by the recovery of AGP's fluorescence as the quenching probe was displaced from its high-affinity site, was characterized by inhibitory dissociation constants for the various LAs. The importance of electrostatic factors was assessed by examining the pH dependent binding of an ionizable LA, lidocaine, using the quaternary lidocaine derivative QX-314 [N-(2,6-dimethylphenylcarbamoylmethyl) triethylammonium chloride] to control for pH dependent ionization of AGP. Uncharged lidocaine bound with at least 8 times the affinity of protonated lidocaine (K(D) = 4.0 +/- 0.6 microM and >32 microM, respectively). This result is inconsistent with the current model of the AGP-binding site, which depicts a buried pocket having a negatively charged region that interacts with the amino termini of basic drugs. Consistent with the model, however, two sets of structurally homologous LAs (mepivacaine, ropivacaine, bupivacaine, and lidocaine, RAD-240, RAD-241, RAD-242, L-30, W-6603) demonstrated a strong positive correlation between hydrophobicity (measured as the octanol:buffer partition coefficient of the neutral species) and their free energies of dissociation. Given that the tertiary structure of AGP has proven refractory to resolution, these structure-activity studies should contribute to understanding the nature of the binding site on this important protein.     

Orexin A immunoreactivity and preproorexin mRNA in the brain of Zucker and WKY rats

The primary role of the orexins was originally believed to be appetite regulation, but is now believed to be the regulation of sleep, arousal and locomotor activity. Orexin A immunoreactivity (orexin A-IR) and prepro-orexin mRNA were measured in the CNS of obese and lean Zucker rats. There were no differences in orexin A-IR or prepro-orexin mRNA levels between obese and lean Zucker rats. The orexins are therefore unlikely to be important in this model of obesity. Levels of orexin A-IR and prepro-orexin mRNA were measured in the CNS of Wistar-Kyoto (WKY) rats, which are hypoactive and have abnormal sleep architecture. Compared to Wistar rats, WKY rats had significantly lower orexin A-IR (with differences of up to 100% in some brain regions) and prepro-orexin mRNA levels. These observations suggest that the sleep and activity phenotype of the WKY strain may be related to orexin deficiency and that this strain may be a useful model of partial orexin deficiency.     

Using coronary calcification scanning in the clinical practice of preventive cardiology

Preventive therapies such as cholesterol reduction significantly reduce the risk of acute coronary events. Diagnostic tools that identify asymptomatic coronary atherosclerosis would permit initiation of aggressive preventive therapies at an earlier stage of coronary disease. Histologic and angiographic data demonstrate that coronary calcium has a very high sensitivity for the presence of coronary plaque. Therefore, coronary calcification can be regarded as a marker for coronary atherosclerosis. Coronary calcium scanning has been suggested as a tool for identification of a high-risk asymptomatic patient group. It can be utilized to guide the aggressiveness of risk factor modification and therapeutic preventive interventions toward those at higher risk for future events. Based on the available data, we review the clinical use of coronary calcium scanning in preventive cardiology.