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A New York City homicide case was investigated at the request of the District Attorney's office. The deceased had been violently beaten about the face, neck, and chest area. The bludgeoning left the victim unrecognizable, and produced blood-spatter patterns at the scene that attained heights over nine feet. The suspect claimed that he reacted in self-defense to the victim's attack with a table leg at which point he "knocked him down" and possibly "kicked him a few times." Our investigation was intended to determine whether the bloodspatter patterns observed at the crime scene were consistent with the statements made by the defendant. Conclusions were drawn from an analysis of the crime scene, autopsy photos and report, physical evidence submitted to the laboratory, and reconstruction experimentation performed at the Office of Chief Medical Examiner (OCME). The spatter patterns observed at the scene were found to be consistent with those that would be produced from a "stomping" incident.

The identification of the hallucinogen, 2,5-dimethoxy-amphetamine, in illicit seizures using spectroscopic techniques is described. The difficulties in the interpretation of the IR spectra as a result of positional isomers and also the anomalies found during GC analysis are covered. The NMR and mass spectroscopic data are explained.

Heart cells growing as monolayer cells in tissue culture have the ability to beat (1) . After several day in culture these same cells cease functioning and lose the morphology characteristic of beating cells . This process by which heart cells lose their ability to beat in culture has been described as dedifferentiation (2) . While studying the effect of steroids on beating, McCarl et al . (3) demonstrated that cortisol not only will enhance the per cent of beating in heart cell cultures, but also will re-initiate beating in those cells which have ceased to function . Thus, cortisol restores and maintains the functionally differentiated state of the heart cell in culture . Since cortisol is instrumental in maintaining the differentiated state of heart cells in culture, studies were performed to determine how the hormone controls the beating phenomenon in heart cells . This report is concerned with the effects of cortisol on RNA and protein synthesis in heart cells and their relationship to beating.

The screening of autopsy specimens, vaginal, buccal, and rectal swabs, for the presence of seminal fluid in rape homicide investigations utilizing classical techniques can lead to erroneous results. In the absence of spermatozoa, techniques are needed which can help to identify seminal fluid. This report illustrates the use of a multi-enzyme electrophoretic approach identifying seminal acid phosphatase (SAP) and lactic acid dehydrogenase (LDH-X) as an initial screening procedure. Subsequent analyses for the presence of acid and alkaline phosphatase (semiquantitative) yield information which can help identify false-positive SAP's. Additionally, salivary amylase can be tentatively identified using the same multi-enzyme procedure which informs the investigator of possible salivary contamination of the sample and possible erroneous PGM results. Statistics utilizing the multi-enzyme approach in case work are also presented.

DNA purified from more than 170 forensic samples was characterized by restriction fragment length polymorphism analysis. DNA isolated from dried blood stains, various tissues, and semen stains was digested with the restriction endonuclease Pst 1, size separated by agarose gel electrophoresis, transferred to nylon membrane and hybridized with IM probes which recognize hypervariable regions in the human genome. The size of DNA fragments, reacting to these probes, was measured with a computer assisted digitizing system and a likelihood of identity calculated from databases containing the frequency of the alleles identified with each probe. The combined discrimination potential with 4 DNA probes that hybridize to hypervariable regions is greater than 108. The present report also summarizes some of our experience in the analysis of forensic biological evidence.

Deoxyribonucleic acid (DNA) was recovered from dried bloodstains aged up to three years and shown to be of high molecular weight. DNA was digested with restriction endonucleases and fractionated by agarose gel electrophoresis. Following transfer to a filter, DNA was hybridized with two different radioactively labeled recombinant probes which recognize highly polymorphic regions in human DNA. The autoradiographic pattern observed was not altered by sample age, and the size of the alleles was consistent with those observed in the general population. Therefore, DNA of high molecular weight prepared from dried blood samples can be used for identification.

We have examined the possibility of using DNA purified from dried blood stains for the analysis of restriction fragment length polymorphisms. High molecular weight DNA was recovered from blood dried on cotton cloth, aged from one day to three years. These DNA samples were digested with restriction endonucleases, separated by agarose gel electrophoresis and hybridized to recombinant DNA probes that recognize two different highly polymorphic DNA sequences. A set of controlled samples was aged at room temperature for up to 28 days. The polymorphic DNA pattern observed with each probe remained the same at all time points. The patterns of DNA polymorphisms observed in the two and three year old dried blood stains was consistent with patterns observed in the general population. These results indicate that DNA recovered from dried blood stains can be used for identification purposes.

A literature search concerning methods of analysis of fibers for forensic purposes has been completed. The results suggest that combined pyrolysis-gas chromatography (PGC) meets all the requirements for use in forensic analyses. Data are presented from a collaborative study conducted by the Institute of Petroleum, Gas Chromatography Discussion Group, concerning the use of PGC for polymer analysis. Their results suggest that with standardized techniques PGC would provide interlaboratory reproducibility.

This study was designed to analyze the effects of common environmental insults on the ability to obtain deoxyribonucleic acid (DNA) restriction fragment-length polymorphisms (RFLP) patterns from laboratory prepared specimens. The environmental conditions studied include the exposure of dried bloodstains to varying amounts of relative humidity (0, 33, 67, and 98%), heat (37 degrees C), and ultraviolet light for periods of up to five days. In addition, the effect of drying over a four-day period in whole blood collected with and without ethylenediaminetetraacetate (EDTA) was examined. The results of the study showed that, under the conditions studied, the integrity of DNA is not altered such that false RFLP patterns are obtained. The only effect observed was that the overall RFLP pattern becomes weaker, but individual RFLP fragments are neither created nor destroyed.

This study was designed to analyze the effects of the environment and substrata on the quality of deoxyribonucleic acid (DNA) isolated from evidentiary specimens. The quality of DNA isolated from actual casework specimens was determined by measuring its size by agarose gel electrophoresis. The information obtained could be used to predict the suitability of the DNA in the samples for restriction fragment length polymorphism (RFLP) analysis. The evidentiary specimens chosen for DNA were classified according to substrate (scrapings, plastic bags, synthetics, denim, and carpet) and according to a subjective evaluation of the condition of the stain (soiled, damp, or putrefied) and to its size (small or large). The results show that DNA of sufficient quality and high molecular weight (HMW) can be reliably isolated from bloodstains deposited on evidentiary items which have an unknown environmental history and which have dried onto a variety of substrata. Subsequent RFLP analysis of a selected number of these samples verified that the DNA was suitable for this type of analysis.