Acute effects of carbon monoxide and cyanide on hepatic mitochondrial function

The effects of carbon monoxide and cyanide on the hepatic redox state and energy charge were investigated. Rats were used for the experiment under pentobarbital anesthesia. Immediately after laparotomy, a rat was placed in an animal chamber made of a transparent plastic box and exposed to a test gas for 3 min. Every test gas was produced in a gas chamber connected to the animal chamber with a flexible tube. HCN was produced from NaCN and H2SO4. In the CO inhalation experiment, various amounts of CO were introduced into the gas chamber. Immediately after an exposure, about 2 g liver was frozen in situ with a precooled clamp. Oozed blood from the wound surface was sampled. Concentrations of ATP, ADP, AMP, acetoacetate, and beta-hydroxybutyrate in hepatic mitochondria were determined, and the redox state and the energy charge were calculated. For cyanide as well as CO, significant negative correlations were found between the concentration in the blood and the redox state. The same held true for the energy charge. The redox state showed a slight increase at low concentrations of both gases; however, thereafter it began to decrease sharply with increases in concentrations. When concentrations of the toxicant in the blood reached certain levels, a kind of turning point, beyond which the redox state does not decrease any more, was observed. It was about 40% for HbCO and about 2.0 micrograms/ml for cyanide, and the points seemed to be related to the concentrations, beyond which cells are irreversibly damaged. On the other hand, the energy charge did not change at low concentrations. With an increase in toxicant concentrations, the energy charge decreased drastically. The rate of decrease in the energy charge became higher when blood concentrations exceeded certain levels. It was about 40% for HbCO and 2.0 micrograms/ml for cyanide. The presence of low levels of blood cyanide did not affect the relationship between the energy charge and the HbCO concentration.     

Aging studies on fingerprint residues using thin-layer and high performance liquid chromatography

The chemical substances of perspiration found in latent fingerprint residue may hold the key for dating latent fingerprints. To study the chemical transformations of these components as a function of time and environment, fingerprint residues from four males and four females were analysed by thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC). Three major and two or three minor components were detected by both methods and the variation in the quantity of the major components with time was observed.     

Accidental poisonings involving carbon monoxide, heating systems, and confined spaces

Eleven incidents of carbon monoxide (CO) intoxication resulting in sixteen fatalities are reported. All of the cases involved heating systems as either the source or the means of distributing the CO. Blood samples were analyzed for ethanol and CO. Elevated blood CO saturations were found in 14 of the 16 victims while none of the victims had a blood ethanol concentration greater than 0.10% (w/v).     

Genetic polymorphism at three STR loci--CSF1PO, HUMTHO1 and TPOX, and the AMP-FLP locus D1S80 for the Chinese population in Hong Kong

Allele frequencies for three STR loci, namely, CSF1PO, HUMTHO1 and TPOX, and the AMP-FLP locus D1S80 were obtained from a sample of 351 unrelated Chinese in Hong Kong.     

Pesticide poisoning initially suspected as a natural death

A pesticide poisoning victim suspected initially as having died a natural death was autopsied. The victim was a 47-year-old male. Macroscopically, signs of acute death and, in particular, general erosion in the mucosa of the airways and esophagus were observed. In the gastric contents, which had a pungent smell and a greenish-brown color, 5.00 g/L of propanil, 1.27 g/L of carbaryl, 0.38 g/L of ethylbenzene, and 0.32 g/L of xylene were detected. In the blood (serum), 21.6 mg/L of propanil, 8.1 mg/L of carbaryl, 1.7 mg/L of ethylbenzene, and 4.0 mg/L of xylene were identified. Postmortem methemoglobinemia (45%) was recognized. The cause of death was considered to have been pesticide poisoning; propanil was probably most responsible for his death. The police considered the case to be "death with illness as the suspected cause." By performing an autopsy, however, we were able to clarify that the cause of death was pesticide poisoning.     

Spectra interference between diquat and paraquat by second derivative spectrophotometry

A rapid and accurate method, combining solid-phase extraction and second-order derivative spectrophotomety approaches, is developed for the simultaneous determination of diquat (DQ) and paraquat (PQ) in blood, tissue and urine samples. Supernatant resulting from the precipitation of protein (with trichloroacetic acid) in plasma and tissue or Amberlite IRA-401 resin treated urine are passed through a mini-column packed with Wakogel gel (Silica gel). Analytes are then eluted with a non-organic solvent, 0.2mol/l HCl solution containing 2mol/l NH(4)Cl. UV spectrum of the eluent in 220-350nm range provides effective screen to detect the presence of DQ and/or PQ. In the presence of DQ or PQ alone, the analyte present is quantitated by conventional zero- or second-order derivative spectrophotometry. The calibration curve in the 0.1-5.0mg/l range for either analyte obeys Beer's law. When both DQ and PQ are present, their concentrations are determined by the peak amplitudes of their respective second-derivative spectra after the addition of alkaline dithionite reagent. Interference is negligible when the DQ/PQ concentration ratio is within the 5.0-0.2 range.Using a 2-ml of sample size, the detection limits for DQ and PQ in plasma are 0.02 and 0.005mg/l. The corresponding detection limits for urine samples (10ml sample size) are 0.004 and 0.001mg/l. Recoveries of DQ and PQ in triplicate plasma and urine samples spiked with 0.5mg/l of analytes are 93 and 85%. The precision of the proposed method resulting from triplicate study of spiked urine samples varies from 3.2 to 4.6% at 0.5mg/l of DQ and PQ, respectively.     

Posttraumatic thrombosis of the middle cerebral artery

Posttraumatic cerebral infarction resulting from carotid or cerebral artery occlusion is rare. Traumatic dissection of the carotid artery is the most frequent cause of infarction, whereas posttraumatic thrombosis of the cerebral artery is very rare. The authors describe a case of posttraumatic thrombosis of the left middle cerebral artery. Early in the morning, a 16-year-old boy was found unconscious in the parking lot of a supermarket. He had received fist blows and kicks to the head, face, body, back, and hip during the night. Computed tomography 10 hours after the violence revealed a gross cerebral infarction in the area of the left middle cerebral artery. He died 9 days after the violence. The autopsy revealed a thrombosis in the left middle cerebral artery. Microscopically, granulation tissue in the intima and a rupture of the internal elastic lamina were observed near the beginning of the artery. It was concluded that the blows to the head and face caused a partial rupture in the arterial wall, leading to thrombosis and cerebral infarction.     

Cytochrome b gene for species identification of the conservation animals

A partial DNA sequence of cytochrome b gene was used to identify the remains of endangered animals and species endemic to Taiwan. The conservation of animals species included in this study were: the formosan gem-faced civets, leopard cats, tigers, clouded leopards, lion, formosan muntjacs, formosan sika deers, formosan sambars, formosan serows, water buffalo, formosan pangolins and formosan macaques. The control species used included domestic cats, domestic dogs, domestic sheeps, domestic cattles, domestic pigs and humans. Heteroplasmy was detected in the formosan macaque, domestic pig and domestic cats. The frequencies of heteroplasmy in these animals were about 0.25% (1 in 402bp). Sequences were aligned by Pileup program of GCG computer package, and the phylogenetic tree was constructed by the neighbor-joining method. The results of sequence comparison showed that the percentage range of sequence diversity in the same species was from 0.25 to 2.74%, and that between the different species was from 5.97 to 34.83%. The results of phylogenetic analysis showed that the genetic distance between the different species was from 6.33 to 40.59. Animals of the same species, both the endangered animal species and domestic animals, were clustered together in the neighbor-joining tree. Three unknown samples of animal remains were identified by this system. The partial sequence of cytochrome b gene adopted in this study proved to be usable for animal identification.     

Limits of the Lamendin method in age determination.

This study shows that epithelial attachment level, used as age determination criterion in Lamendin's method, is not reliable for adults of either sex above the age of 49 years with periodontal diseases in any quadrant. The underestimation of calculated age increases from 7 to 19 years with chronological age. On the other hand, the present paper confirms the pertinence of dentin translucency as an age indicator in Lamendin's method.