Biomedical subjects

J Subke

Publications and source records attributed to J Subke.

9 recordsLinked to original sources

PubMed2004

[Observation and control of hepatic specimens with MRI and MRS].

PURPOSE: The purpose of this study was to observe the process of fixation in liver specimens non-invasively by means of magnetic resonance. The fixation process of several formaldehyde-containing solutions was monitored with MRI and MRS at two different temperatures. MATERIALS AND METHODS: Liver specimens were conserved in aqueous fixative solutions containing formaldehyde concentrations of 0.7, 1.8, 4 and 7.2 % and at different temperatures of 5 degrees C and 20 degrees C. MRI was performed with T1-, T2- and PD-weighted TSE sequences, a 2D FLASH-sequence with and without magnetization transfer, and a FISP 3D-sequence on a clinical 1.5 Tesla MR whole-body unit, and MRS with (1)H-spectroscopic methods (STEAM-sequence) on a 3 Tesla MR whole-body unit. RESULTS: The diffusion of formaldehyde into the tissue was best identified on PD- and T1-weighted images as a band under the liver surface with increasing thickness, penetrating especially fast during the first three days. Spectroscopic measurements revealed the rising formaldehyde concentration in the inner part of the organs. Temperature had no significant influence on the velocity of immersing, but cooling conditions produced less gas-filled caverns due to reduced undesired decomposition processes. CONCLUSION: The spatial and temporal process of ongoing fixation in the liver can be monitored by MRI. MRS confirms a rising concentration of formaldehyde during ongoing fixation.

Fixatives↗

PubMed2001

Delimitation of the time of death by immunohistochemical detection of glucagon in pancreatic alpha-cells.

To improve the possibilities of delimitating the time of death after longer laytime it was examined if this is possible by immunohistochemical glucagon detection. The results show that in our examination material the pancreatic alpha-cells of up to 6-day-old corpses produce a positive immunoreaction towards glucagon in all cases whereas none of the corpses older than 14 days show such a reaction. This means that in the case of a negative immunoreaction the time of death can be assumed to lie more than 7 days before the autopsy. The fact that a negative immunoreaction occurs consistently after 14 days leads to the conclusion that when glucagon has been stained in a specimen, the death of the respective person must lie a maximum of 13 days earlier, whereby under markedly different conditions to the ones of the cases here examined, a negative immunoreaction could happen earlier and a positive immunoreaction even later.

Autopsy↗

PubMed2001

Delimitation of the time of death by immunohistochemical detection of calcitonin.

To improve the possibilities of delimitating the time of death after longer laytime it was examined if this is possible by immunohistochemical detection of calcitonin. The results show that in our examination material the c-cells of the thyroid glands of up to 4-day-old corpses produce a positive immunoreaction towards calcitonin in all cases whereas none of the corpses older than 13 days show such a reaction. This means that in the case of a negative immunoreaction the time of death can be assumed to lie >4 days before the autopsy. The fact that a negative immunoreaction occurred consistently after 13 days leads to the conclusion that when calcitonin has been stained in a specimen, the death of the respective person must lie a maximum of 12 days earlier, whereby these time-limits may change in considerably different surrounding conditions.

Calcitonin↗

PubMed2000

Streifenlichttopometrie (SLT): a new method for the three-dimensional photorealistic forensic documentation in colour.

By means of the new method of Streifenlichttopometrie (SLT) it is possible to record the complete body surface of casualties in a practically photorealistic fashion, i.e. three-dimensionally and in colour. In comparison with the classic method of Photogrammetry Streifenlichttopometrie (SLT) is remarkably faster (10,000 points/s instead of 1 point/s) and in addition the colour of every point measured upon the corpse's surface is instantly recorded. Taking into consideration the resolution required and the qualities of the camera system the body surface is recorded in 'patches', i.e., areas of a defined extension (in the present case 500 mmx500 mmx200 mm) which are marked with a body fixed reference frame to grant the exact matching of the data after the recording process. Length, perimeter, square and volume of the body segments and injuries can be determined. Furthermore the natural colour of the wounds can be used for an immediate classification according to the intensity of the impact forces. In addition the 3-D coordinates of the body surface including the wounds can be transferred into an animated computer simulation for the reconstruction of the traumatic events.

Accidents↗

PubMed2000

Immunohistochemical detection of methadone in the human brain.

To develop a method of detecting methadone in the human brain by immunohistochemistry, brain tissue of frontal cortex, cerebellum, hippocampus, basal ganglions and brain stem from victims of a lethal methadone overdose was examined. The staining was performed with a monoclonal anti-methadone antibody from the mouse, originally developed for immunochemichal purposes (ELISA). With the help of the DAKO((R)) Catalyzed Signal Amplification (CSA) System, a specific positive immunoreaction was obtained in the neurons of the frontal cortex and hippocampus, as compared with specimen from deaths without exposition to methadone. Thus, along with metamphetamine, phenobarbital, morphine and insulin, immunohistochemical detection is also possible for methadone and the intake of this medicament can now be proven morphologically.

Adult↗

PubMed2000

Delimitation of the time of death by immunohistochemical detection of thyroglobulin.

To improve the possibilities to delimit the time of death after longer laytime it was examined if this is possible by immunohistochemical detection of thyroglobulin. The results show that in our examination material the colloid and the follicular cells of the thyroid glands of up to 5-day-old corpses produce a positive immunoreaction towards thyroglobulin in all cases whereas none of the corpses older than 13 days show such a reaction. This means that in case of a negative immunoreaction the time of death can be assumed to lie more than 6 days before the autopsy. The fact that a negative immunoreaction occurs consistently after 13 days leads to the conclusion that when thyroglobulin has been stained in a specimen, the death of the respective person must lie a maximum of 12 days earlier, whereby these time-limits may change in considerably different surrounding conditions.

Death↗

PubMed2000

Demonstration of morphine in ganglion cells of the hippocampus from victims of heroin overdose by means of anti-morphine antiserum.

To investigate the topography of morphine distribution in the human brain, a method has been developed to detect morphine immunohistochemically. In this study hippocampus tissue from victims of heroin overdose (blood morphine concentrations 220 ng/g-1500 ng/g; 6-MAM positive urine sample), known for its high concentration of mu-opiate receptors was used. The immunohistochemical staining was performed with an anti-morphine antiserum originally developed for radio-immunoassays. In comparison with control specimens from cases of sudden death without morphine exposition or a history of heroin abuse, the brains from victims of heroin overdose showed selectively stained ganglion cells, axons and dendrites, suggesting a massive concentration of morphine in the neuronal structures.

Adult↗

PubMed1999

Delimitation of the time of death by immunohistochemical detection of insulin in pancreatic beta-cells.

To improve the possibilities to delimitate the time of death after longer laytime, it was examined if this is possible by immunohistochemical insulin detection. The results show that in our examination material, the pancreatic beta-cells of up to 12-day-old corpses produce a positive immunoreaction towards insulin in all cases, whereas none of the corpses older than 30 days show such a reaction. This means that in case of a negative immunoreaction, the time of death can be assumed to lie more than 12 days before the autopsy. The fact that a negative immunoreaction occurs consistently after 30 days leads to the conclusion that when insulin has been stained in a specimen, the death of the respective person must lie a maximum of 29 days earlier, whereby these time-limits may change in considerably different surrounding conditions.

Autolysis↗

PubMedDate not supplied

[Gunshot reconstructions based on individually parametrical 3-dimensional victim models].

In cases of lethal firearm injuries computer enhanced anatomical feasibility studies can provide unambiguous clues concerning self-versus extraneous infliction. To this end individualized digital 3-dimensional geometrical models of the victim and the weapon are generated true to scale with the help of the CAD software (POSER Version 4, egi.sys AG). All anatomical data relevant to the motion apparatus and the range of movement as well as the injuries of the individual victim are carefully documented and serve as input parameters for the digital geometrical model. The bullet path is visualized as a cylinder between entrance and exit wound. A series of simulation sequences then can be carried out by the variation of anatomically possible shot positions and the virtual grasp of the weapon. An exact alignment of the firearm's barrel and the bullet path is a reliable statement for the feasibility of self-infliction. In addition to circumstantial evidence the digital reconstruction of the firearm shot admits of unambiguous conclusions about the course of the traumatic event.

Adult↗