Effect of sodium hypochlorite decontamination on the DNA recovery from human teeth

Genetic identification of skeletal human remains is often realized by short tandem repeat (STR) genotyping of nuclear DNA. Dental DNA is preferred to DNA from bone for the better protection of the endogenous DNA. Especially if whole tooth grinding is intended to access the DNA, contaminations with exogenous DNA have to be avoided. The immersion of the tooth in sodium hypochlorite (NaOCl, known as bleach) is one common procedure to clean the outer surface from extraneous DNA and PCR inhibitors. To investigate the impact of bleaching on endogenous DNA and the decontamination success, 71 recently extracted teeth were differently treated with sodium hypochlorite (2.5 or 5.0% NaOCl for 30 or 60 s, 5.0% NaOCl for 10 min, and control group) in the beginning of the extraction process, whereas equally handled afterwards. Quantitative and qualitative evaluation of the extracted DNA was performed. There was a great variation for the DNA concentration of the extracts even within a group of the same NaOCl treatment. Complete DNA profiles from single persons with alleles for the 16 ESS (European Standard Set) STR loci were obtained for all regarded teeth. A statistically significant difference between the DNA yields of the treatment groups was not determined. Moreover, a negative effect of NaOCl (2.5% and 5.0%) on the DNA recovery could not be observed. Significant larger amounts of DNA were extracted from anterior teeth in contrast to posterior teeth.     

Ängste und Stress infolge der Corona-Krise

Zeitschrift für Psychodrama und Soziometrie - Dieser Beitrag der Zeitschrift für Psychodrama und Soziometrie zeigt auf, wie die Corona-Pandemie und ihre Begleiterscheinungen das...     

A detailed report on the measures taken in the Department of Conservative Dentistry and Periodontology in Munich at the beginning of the COVID-19 outbreak

Clinical Oral Investigations - The corona disease (COVID-19) is developing into one of the greatest challenges for healthcare professionals around the world. In this article, we report the detailed...     

Estimating cumulative incidence functions in competing risks data with dependent left-truncation

Both delayed study entry (left-truncation) and competing risks are common phenomena in observational time-to-event studies. For example, in studies conducted by Teratology Information Services (TIS) on adverse drug reactions during pregnancy, the natural time scale is gestational age, but women enter the study after time origin and upon contact with the service. Competing risks are present, because an elective termination may be precluded by a spontaneous abortion. If left-truncation is entirely random, the Aalen-Johansen estimator is the canonical estimator of the cumulative incidence functions of the competing events. If the assumption of random left-truncation is in doubt, we propose a new semiparametric estimator of the cumulative incidence function. The dependence between entry time and time-to-event is modeled using a cause-specific Cox proportional hazards model and the marginal (unconditional) estimates are derived via inverse probability weighting arguments. We apply the new estimator to data about coumarin usage during pregnancy. Here, the concern is that the cause-specific hazard of experiencing an induced abortion may depend on the time when seeking advice by a TIS, which also is the time of left-truncation or study entry. While the aims of counseling by a TIS are to reduce the rate of elective terminations based on irrational overestimation of drug risks and to lead to better and safer medical treatment of maternal disease, it is conceivable that women considering an induced abortion are more likely to seek counseling. The new estimator is also evaluated in extensive simulation studies and found preferable compared to the Aalen-Johansen estimator in non–misspecified scenarios and to at least provide for a sensitivity analysis otherwise.     

Hemoglobin,alkalic phosphatase,and C‐reactive protein predict the outcome in patients with liposarcoma

Data on prognostic biomarkers in soft tissue sarcomas are scarce. The aim of the study was to define prognostic markers in patients with a liposarcoma, a subtype of sarcoma derived from adipose tissue. We restrospectively reviewed 85 patients with liposarcoma treated at our department from May 1994 to October 2011. Kaplan–Meier curves, uni‐, and multivariable Cox proportional hazard models and competing risk analysis were performed to evaluate the association between putative biomarkers with disease‐specific and overall survival. We observed a significant association between both alkalic phosphatase (ALP; subhazard ratio [SHR] per 1 unit increase: 1.35; 95%CI 1.10–1.65; p = 0.005) and C‐reactive protein (CRP; SHR per 1 mg/dl increase: 2,57; 95%CI 1.36–4,86; p = 0.004) with disease‐specific survival. Hemoglobin (Hb) (HR per 1 g/dl increase: 065; 95%CI 0.48–0.87; p = 0.003) was associated with overall survival. These associations prevailed after multivariable adjustment for AJCC tumor stage. This study identifies CRP and ALP as novel independent predictors of disease‐specific survival in patients with liposarcoma. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:765–770, 2015.