Is immunohistochemistry a useful tool in the postmortem recognition of myocardial hypoxia in human tissue with no morphological evidence of necrosis?

Myocytes in the border zone of myocardial infarction are under severe hypoxia without characteristic morphology of necrosis, and show ultrastructural features similar to those seen within the first hours after coronary occlusion. This study was carried out to evaluate the possibility that immunohistochemical methods could be used for the early diagnosis of myocardial infarction by detecting areas of hypoxia. Nineteen human sections of formalin-fixed paraffin-embedded myocardial samples showing a necrotic area and its border were submitted to immunohistochemical staining with the markers antimuscle actin, antimyoglobin, antitroponin T, antifibronectin, and anticomplement component C9. Sections were also subjected to azan trichrome and hematoxylin-basic fuchsin-picric (HBFP) staining techniques. Immunohistochemistry and azan trichrome showed that in the border zone there was a pattern of reaction intermediate between the infarcted area and the normal myocardium. The HBFP failed to distinguish these two areas. In conclusion, immunohistochemistry and azan trichrome can recognize myocardial hypoxia. Because hypoxia is an invariable condition in infarction, these techniques can be used to confirm suspected cases of myocardial infarction in which necrosis is not yet evident. However, considering that agonal states may be associated with generalized hypoxia, further studies are needed to confirm the reliability of this procedure in the earlier phases of myocardial infarction.     

Forensic comparison of soils by bacterial community DNA profiling

This preliminary investigation has shown that a soil microbial community DNA profile can be obtained from the small sample of soil recovered from the sole of a shoe, and from soil stains on clothing. We have also shown that these profiles are representative of the site of collection and therefore could potentially be used as associative evidence to prove a link between suspects and crime scenes. Soil community profiles were obtained using the T-RFLP fingerprinting method that uses fluorescent primer technology and semi-automated analysis techniques similar to those used in human DNA profiling in forensic laboratories.     

A Fast, Easy, and Efficient Estimator for Multiparty Electoral Data

Katz and King have previously developed a model for predictingor explaining aggregate electoral results in multiparty democracies.Their model is, in principle, analogous to what least-squaresregression provides American political researchers in that two-partysystem. Katz and King applied their model to three-party electionsin England and revealed a variety of new features of incumbencyadvantage and sources of party support. Although the mathematicsof their statistical model covers any number of political parties,it is computationally demanding, and hence slow and numericallyimprecise, with more than three parties. In this paper we producean approximate method that works in practice with many partieswithout making too many theoretical compromises. Our approachis to treat the problem as one of missing data. This allowsus to use a modification of the fast EMis algorithm of King,Honaker, Joseph, and Scheve and to provide easy-to-use software,while retaining the attractive features of the Katz and Kingmodel, such as the t distribution and explicit models for uncontestedseats.     

Fairness and Rejection in the Ultimatum Bargaining Game

The ultimatum game is a standard instrument for laboratory experimentalists.It has been replicated in a large number of environments andpoints to special considerations for fairness. Although it hasbeen popular in the experimental community, researchers havenot harnessed all the statistical power they should to evaluatethe dynamics at work in this type of a bargaining game. Thisresearch uses two planned treatments, the first involving asignaling condition concerning a subject's "type," and the seconda price effect built into the structure of the game. We findthat there are no significant main effects as a result of thesignaling condition of a subject's type, but that there arestrong effects as a result of the different payoff parameters.Using a variety of multivariate models we find important, nonobviousinteractions with the gender of the subjects. The lesson thatwe take away from this research is that experimentalists canlearn more from data collected in the tightly controlled laboratoryenvironment by using statistical techniques that complementtheir research designs.     

Virtopsy: postmortem minimally invasive angiography using cross section techniques--implementation and preliminary results

Postmortem investigation is increasingly supported by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). This led to the idea to implement a noninvasive or minimally invasive autopsy technique. Therefore, a minimally invasive angiography technique becomes necessary, in order to support the vascular cross section diagnostic. Preliminary experiments investigating different contrast agents for CT and MRI and their postmortem applicability have been performed using an ex-vivo porcine coronary model. MSCT and MRI angiography was performed in the porcine model. Three human corpses were investigated using minimally invasive MSCT angiography. Via the right femoral artery a plastic tube was advanced into the aortic arch. Using a flow adjustable pump the radiopaque contrast agent meglumine-ioxithalamate was injected. Subsequent MSCT scanning provided an excellent anatomic visualization of the human arterial system including intracranial and coronary arteries. Vascular pathologies such as calcification, stenosis and injury were detected. Limitations of the introduced approach are cases of major vessel injury and cases that show an advanced stage of decay.     

STR-typing of human DNA from human fecal matter using the QIAGEN QIAamp stool mini kit

The purpose of this study was to compare the effectiveness of the QIAGEN QIAamp Stool Mini Kit against a standard phenolchloroform procedure for the extraction, quantitation, and STR-typing of human nuclear DNA from human feces. Stools from six subjects were sampled by swabbing and excision. Samples extracted with the QIAamp kit gave a wide range of DNA yields, whereas those extracted by the organic method yielded no DNA. DNA was not recovered from one subject's stools by either procedure. The QIAamp extracts were amplified with the Profiler Plus and COfiler kits, and PCR inhibition was observed with DNA extracts that were further concentrated. Substitution of water or TE-4 for the QIAamp elution buffer eliminated most, if not all, of the inhibition. A modified QIAamp procedure was used to extract thirty samples, which were subjected to one of five environmental conditions. DNA was recovered from all of these samples, and typing results were obtained on 93% of the samples.