Biomedical subjects

J Sammler

Publications and source records attributed to J Sammler.

4 recordsLinked to original sources

PubMed1997

Identification of fatty acid methyl esters (FAMEs) in postmortem tissue. A new marker of alcohol abuse?

Based on a method that combines thin layer chromatography and gas chromatography, it proved possible to detect postmortem fatty acid methyl esters (FAMEs) in human tissues (pancreas, liver, heart and adipose tissue). The highest concentrations were found in the pancreas, medium concentrations in the liver and adipose tissue and the lowest concentration in heart tissue. All tissues contained higher concentrations of unsaturated FAMEs than saturated FAMEs. In order to evaluate the influence of alcohol consumption on the formation of FAMEs, the decreased were divided into three groups: control group, chronic alcoholics (who were alcohol free at the time of death), and acutely alcohol-intoxicated subjects (so intoxicated at the time of death with no evidence of chronic alcohol abuse). In comparison to the control group, the organs of the chronic alcoholics showed only slight values, the tissues of the acutely intoxicated subjects were obviously higher. Based on the varying concentration distribution in the three groups, it seemed that postmortem differentiation of the alcohol consumption which existed before the time of death would be possible. After further investigation with a greater number of samples, FAMEs could become a useful supplement to existing alcohol markers in the future.

Adipose Tissue↗

PubMed1992

[Precision control in blood alcohol determination].

The German supreme court (BGH [1]) summons that by proclaiming four or five single measuring values of every blood alcohol determination to prove that the resulting standard deviation lies under the highest amount stated in the official verdict of 1989 (10). On the one hand the control of the proceedings must be guaranteed by the successful participation of the ring tests, yet on the other hand the evidence to retroactively prove the accuracy of every blood alcohol determination from it's single values is always called for anew. In the example case the average value is 1.11 g/1000, the standard deviation is 0.036 g/1000. The standard deviation summoned by the BGH (1) is thereby exceeded. On account of the fundamental scientific regularies the parameter standard deviation is not qualified to retroactively verify the required accuracy of the procedure by means of the single values. The blood alcohol result in question can be used without proviso. A reduction of the present approved 10% variation of the single values is not significant. Only according to todays accuracy requirements does this limit nearly appear to be appropriate.

Alcoholic Intoxication↗

PubMed1989

Hypoxia-induced acute changes in capillary and fiber density and capillary red cell distribution in the rat heart.

The influence of acute hypoxia (respiration gas 12%, 10%, and 8% O2 and asphyxia, respectively) on 1) the density of perfused capillaries and muscle fibers, and 2) the capillary red cell distribution was investigated in the left heart of anesthetized rats. To observe capillaries and fibers, fluorescein isothiocyanate-labeled (FITC)-gamma-globulin and lissamine-rhodamine-B200-labeled (RB200) myoglobin were injected intravenously as labels of the perfused intravasal and the extracellular space, respectively. The hypoxic conditions were induced subsequently and maintained for 3 minutes. After this period the heart was rapidly frozen for histological demonstration of the dyes. Ventilation with 12% or 10% O2 did not induce any changes in the density of perfused capillaries; however, 8% O2 in respiration gas did lead to a significant increase (capillaries/mm2: subepicardium, 4,180, controls, 3,620; subendocardium, 3,930, controls, 3,240). A similar increase was found in the asphyxia group (capillaries/mm2: subepicardium, 4,170; subendocardium, 3,700). The increases in the density of perfused capillaries were paralleled by rises in fiber density. This leads to the conclusion that the changes in capillary counts were caused by fiber elongation with a resultant decrease in intercapillary distances. This assumption was supported by observations that there were no signs of changes in ventricular segment length during respiration of 12% or 10% O2 but that an increase did occur with 8% oxygen and with asphyxia. Densities of perfused capillaries exactly coincided with anatomical densities (demonstrated by additional labeling of capillary basement membranes with isolectin B4) in normoxic and asphyctic hearts. The distribution of red cells in the capillaries, determined in histological sections, did not differ appreciably under hypoxia due to reduced O2 in respiration air (12%) or asphyxia. The results obtained indicate that 1) extreme hypoxic states cause the capillaries to move closer to each other due to elongation of myocardial fibers and 2) red cell distribution is not altered during these conditions.

Acute Disease↗

PubMed1984

Method for measurement of heart rate in awake, noninstrumented small mammals.

A method is described that enables the researcher to determine the heart rate in awake, noninstrumented small animals by recording the electrocardiogram (ECG) via the paws. Single animals are placed in a cage that has metal plates built into its floor. Through switches any two plates can be connected with an ECG recorder whenever contact with at least one front and one hind paw is made. The heart rate is then determined by measuring the number of R waves per unit of time. In rats of 140 and 300 g body wt mean resting heart rates of 384 +/- 10 and 320 +/- 4 beats/min, respectively, have been measured with this method.

Animals↗