1. |
- Druid, Henrik, et al.
(author)
-
A compilation of fatal and control concentrations of drugs in postmortem femoral blood
- 1997
-
In: Journal of Forensic Sciences. - 0022-1198 .- 1556-4029. ; 42:1, s. 79-87
-
Journal article (peer-reviewed)abstract
- A compilation of postmortem femoral blood concentrations of drugs is presented. The samples are collected from cases in which the cause of death was: A) certified intoxication by one substance alone, B) certified intoxication by more than one substance and/or alcohol, and C) certified other cause of death without incapacitation due to drugs. The concentrations were compared with blood concentrations detected in suspected drugged drivers (D), and with previously published fatal and therapeutic concentrations. The special features of this compilation are: 1) exclusively femoral blood concentrations are quoted, 2) all analyses are based on samples handled according to a standardized, quality-controlled procedure, 3) two control groups are included, and 4) one-substance-only intoxications are separated from other intoxications. The material is based on a selection of 15,800 samples sent to the Department of Forensic Chemistry in Linkoping, Sweden, during 1992 to 1995 from the six forensic pathology units in Sweden, and the list includes 83 drugs. The compilation includes drugs, where previously published data are scarce. Furthermore, the data gathered from cases with other cause of death than intoxication (group C) constitute a new kind of reference information, which probably offers a better estimate of obviously non fatal levels in postmortem blood than any compilation of therapeutic concentrations in living subjects. The possible factors influencing postmortem drug concentrations are discussed.
|
|
3. |
- Druid, Henrik
(author)
-
Experimental acute ischemic renal failure and anticoagulation
- 1998
-
Doctoral thesis (other academic/artistic)abstract
- This thesis is based on experimental studies on acute renal failure (ARF) in rats. The model employed is that of renal artery clamping, which causes a standardized, ischemic trauma to the kidney. The proximate objective of the investigations was to study iflocal coagulation in the kidney may be induced by a pure ischemic trauma, and whether such a coagulation could be of importance for the development of ARF in this experimental model.The content of isotope-labeled fibrinogen and albumin was determined in postischemic kidneys and controls. After 60rnin of unilateral ischemia, the fibrin(ogen)/degradation products (FIB) and albumin content of the kidney increased rapidly and significantly, approximately averaging 200% of controls. The total kidney weight increased only to 130% of controls. Pretreatment with heparin in a dose of 2000 IU/kg BW, markedly attenuated the increase in kidney weight and content of FIB and albumin.Pretreatment with a lower dose of heparin, 400 IU!kg BW, and warfarin (given intraperitoneally 24 h before the experiment) produced a similar reduction of these parameters, whereas pretreatment with a heparin analog, devoid of anticoagulant effect, did not.In post-ischemic kidneys, scanning electron microscopy (SEM) of cautiously handled freezedried tissue revealed granular and fibrillary material in the tubules and in Bowman's space, at some locations displaying prominent network patterns. Immunofluorescence against FIB showed immunoreactive material in vasa recta, the peritubular capillaries, Bowman's space and in the tubules. By transmission electron microscopy (TEM), fibrin strands lacking periodicity were seen. As compared to controls, the postischemic kidneys generally showed a marked dilatation of Bowman's capsule. No fibrin deposition was seen in heparin pretreated animals.To determine if anticoagulation exerts the described effects by prevention of tubular obstructions or by attenuation of increased glomerular permeability, morphometry of glomeruli was performed by light microscopy and TEM Postischemic kidneys from rats pretreated with saline showed a marked widening of Bowman's space, most likely due to tubular obstruction, whereas Bowman's space width in anticoagulated rats did not differ from controls. Structural changes of the podocyte foot processes as a marker of increased macromolecular permeability were severe in both saline pretreated and anticoagulated kidneys.Glomerular filtration rate fell to 6% of controls after 40 min of ischemia. Warfarin-pretreatment attenuated this decrease significantly. Urinary protein excretion increased in both salinepretreated and anticoagulated rats. The excretion of FIB was significantly increased in warfarinpretreated rats, consistent with the previous observation of an attenuation of FIB content of postischemic kidneys by anticoagulation. This result thus suggests that warfarin did not prevent macromolecular sieving, but reduced the formation of protein-containing tubular casts.In summary, these studies show that a pure ischemic injury to the kidney results in a local coagulation in the kidney, most prominently within Bowman's space and in the tubules. It is suggested that the increased glomerular permeability to macromolecules causes sieving of fibrinogen, which may precipitate in Bowman's space and tubuli and promote the development of tubular obstructions.
|
|