Influence of applied quantity of sunscreen products on the sun protection factor--a multicenter study organized by the DGK Task Force Sun Protection

It is often debated that the protection against solar-induced erythema under real conditions is dependent upon the amount of sunscreen applied. It is believed that when too little is applied a lower sun protection than indicated on the label will result. The aim of this study was to quantify this effect. In this multicenter study, the influence of three different amounts (0.5, 1.0, 2.0 mg/cm(2)) of three commercial sunscreen products in three reliable test centers was investigated according to the test protocol of The International Sun Protection Factor Test Method. The main result was a linear dependence of the SPF on the quantity applied. Taking into consideration the volunteer-specific variations, an exponential dependence of confidence interval of the in vivo SPF and amount applied was found. The highest amount applied (2.0 mg/cm(2)) was linked to the lowest confidence intervals. Thus, from the point of view of producing reliable and reproducible in vivo results under laboratory conditions, the recommendation of this multicenter study is an application quantity of 2.0 mg/cm(2).     

Comparison of quantitative computed tomography-based measures in predicting vertebral compressive strength

Patient-specific measures derived from quantitative computed tomography (QCT) scans are currently being developed as a clinical tool for vertebral strength prediction. QCT-based measurement techniques vary greatly in structural complexity and generally fall into one of three categories: (1) bone mineral density (BMD), (2) "mechanics of solids" (MOS) models, such as minimum axial rigidity (the product of axial stiffness and vertebral height), or (3) three-dimensional finite element (FE) models. There is no clear consensus as to the relative performance of these measures due to differences in experimental protocols, sample sizes and demographics, and outcome metrics. The goal of this study was to directly compare the performance of QCT-based assessment techniques of varying degrees of structural sophistication in predicting experimental vertebral compressive strength. Eighty-one human thoracic vertebrae (T6-T10) from 44 donors cadavers (F=32, M=12; 85+/-8 years old, max=97 years old, min=54 years old) were QCT scanned and destructively tested in uniaxial compression. The QCT scans were processed to generate FE models and various BMD and MOS measures, including trabecular bone mineral density (tBMD), integral bone mineral density (iBMD), and axial rigidity. Bone mineral density was weakly to moderately predictive of compressive strength (R(2)=0.16 and 0.62 for tBMD and iBMD, respectively). In vitro vertebral strength was strongly correlated with both axial rigidity (R(2)=0.81) and FE strength measurements (R(2)=0.80), and the predictive capabilities of these two metrics were statistically equivalent (p>0.05 for differences between FE and axial rigidity). The results of this study indicate that non-invasive predictive measures of vertebral strength should include some level of structural sophistication, specifically, gross geometric and material property distribution information. For uniaxial compression of isolated vertebrae, which is the current biomechanical testing paradigm for new non-invasive strength assessment techniques, QCT-based FE and axial rigidity measures are equivalent predictors of experimental strength. However, before abandoning the FE method in favor of more simplistic techniques, future work should investigate the performance of the FE method versus MOS measures for more physiologically representative loading conditions, e.g., anterior bending or in situ loading with intervertebral discs intact.     

Neurological, neuropsychological, and functional outcome following treatment for unruptured intracranial aneurysms.

The objective of this study was to carry out a detailed investigation of the neurological, neuropsychological, and return-to-work status of treatment for unruptured intracranial aneurysms (UIAs). A prospective design was used to evaluate the outcome of UIA treatment in a group of 26 UIA patients. Over a 24-month period UIA patients were assessed prior to treatment, during hospitalization, at three months and at six months following treatment. Their performance was compared to a group of 20 matched controls. Neurological morbidity as a result of the UIA treatment was 5%, as assessed by the Glasgow Outcome Scale (GOS) or Rankin at 3 months. The Telephone Interview for Cognitive Status (TICS) proved to be unreliable as a measure of cognitive change. Reliability of change analysis was more sensitive than group analysis, and revealed a pattern of cognitive deficits in 10% of patients as a result of the UIA treatment. In addition, 25% of patients reported a change in work role as a result of the UIA treatment. While 10% of patients sustained mild to moderate neurological and cognitive impairments 3 to 6 months following UIA treatment, their deficits were not as wide-ranging nor as severe as those sustained by patients who survive a subarachnoid hemorrhage (SAH).     

Treatment strategy of vascular complications of acute aortic dissection]

Aortic branch occlusion may constitute the mode of presentation or become an important focus of treatment in patients sustaining acute aortic dissection. We reviewed the outcome of 187 consecutive patients (149 males and 38 females, mean age 58 yrs) with acute dissection of the thoracic aorta who were admitted and operated in our clinic during a 13-year period. We assessed the incidence, the consequences and the specific management of stenotic and obstructive lesions of the aorta and its branches. Noncardiac vascular complications occurred in 59 patients (32%); out of these complications, 38 were associated with dissection type A (incidence 28%) and 21 with dissection type B (incidence 48%). Trend towards decreasing overall surgical mortality was observed in the second part (1983-1989) of the study when compared with the first part (1977-1982): it was 28% versus 12%. Although aortic rupture and cardiac tamponade were the strongest correlate of morbidity and mortality, death specifically related to vascular complication was more common when such malperfusion occurred in the carotid, coelio-mesenteric and renal circulation. Proximal aortic repair at the site of the intimal tear with obliteration of the false lumen may have restore adequate distal circulation in 27 patients in whom improvement of the visceral or peripheral ischemia was observed after the thoracic aortic repair. Additional procedures (immediately after the thoracic repair or later on) were necessary in 15 patients to restore adequate perfusion in the compromised area. Early aggressive thoracic aortic repair followed in selected patients by additive vascular procedures can save some patients with compromise visceral or peripheric circulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gender differences in age and BMI distributions in partial upper airway obstruction during sleep

The obstructive sleep apnea-hypopnea syndrome occurs more frequently and with higher apnea-hypopnea indices in men than in women. To investigate the gender differences we extended our respiratory analyses during sleep to cover not only periodic obstruction (apnea and hypopnea) but also nonperiodic partial upper airway obstruction during sleep and their associations with increasing age or body mass index (BMI). The clinical sleep recordings with the static-charge-sensitive bed (SCSB) and oximeter were reviewed in 233 age and BMI-matched men-women pairs. Periodic obstruction increased with increasing BMI only in men. Nonperiodic partial obstruction increased with moderate to morbid obesity in women and men after the age of 65 years. Our findings suggest that while partial upper airway obstruction increases with increasing age and BMI in both genders, men have a gender specific BMI dependent predisposition for periodic obstruction (obstructive sleep apnea). The apnea-hypopnea index is likely to underestimate the impact of sleep-disordered breathing, particularly in elderly patients.     

Standardized definitions of failure modes for female condoms

Definitions of male condom failure modes are now well documented, and failure events are usually reported as the proportion of the total number of condoms used and the proportion of men/couples who experience an event. The lack of standardized definitions for female condom (FC) failure has led to variability in reporting and hence difficulties in making comparisons across studies. As a result, the World Health Organization convened a technical review committee meeting in January 2006 through which the members compiled and agreed to a standard list of terms and definitions for each of the failure modes. These failure modes apply to FCs currently marketed or in advanced stages of clinical testing. They were designed to assist in the review and comparative assessment of different FCs.