Search PubMed⌕ Search

Biomedical subjects

J Rajs

Publications and source records attributed to J Rajs.

At least 37 records · Page 2Linked to original sources
PubMed1996

Hydroperoxide-induced nucleotide degradation and adenosine formation in isolated rat cardiomyocytes.

The effect of tert-butyl hydroperoxide (tBH) on the nucleotide level in isolated cardiomyocytes from adult rats was examined. Incubation of myocytes with the hydroperoxide resulted in loss of both ATP and NAD from mitochondria and cytosol. In contrast, only the cytosolic level of NADP was increased. The effect on myocyte content of ADP and AMP was less pronounced. A significant increase in formation and release of adenosine also occurred in tBH-exposed cells. Treatment of cardiomyocytes with tBH resulted in a progressive decline of rod-shaped and viable cells, which was accompanied by an increase in numbers of hypercontracted and round myocytes in the incubation mixture. Electron microscopic examination showed an intense contraction of the cells. In summary our results demonstrate that plasma membrane damage and hypercontraction are early manifestations of tBH-induced injury to isolated cardiomyocytes. The depletion of ATP and formation of adenosine also suggest that degradation of adenine nucleotides may contribute to the cytotoxicity caused by tBH. Possible mechanisms involved in the ATP depletion are discussed.

Adenine Nucleotides↗
PubMed1996

Pathology of the heart after overhydration with glycine solution in the mouse.

Glycine solution, which is widely used for irrigation in endoscopic surgery, has recently been suspected to have acute or subacute cardiotoxic properties. Therefore, the hearts of 46 mice that survived an intravenous infusion of 0.21/kg glycine 1.1%, 1.5% or 2.2% were examined for pathological alterations between 2 h and 7 weeks after the infusions. Half the animals developed extensive dilatation of the interstitium. Hypoxic events were evidenced by leakage of myoglobin from myocytes in 32 animals and correlated with dilatation of the interstitium. Focal necrosis with an inflammatory cell reaction and replacement of the myocardial tissue with granulation and fibrous tissue were observed after five glycine infusions. Pathological changes were mild or absent in five mice given mannitol solution and in three to which no infusion was given.

Animals↗
PubMed1996

Morphological and X-ray microanalytical changes in mammalian tissue after overhydration with irrigating fluids.

We compared morphological changes in the heart, brain, liver and kidneys after giving 100 ml/kg of 5 irrigating fluids by intravenous infusion to 30 rabbits. Glycine 1.5% and 1.0%, both with ethanol 1% as a tracer for absorption, received the highest scores for tissue swelling and were sometimes followed by focal necrosis and an inflammatory cell reaction in subendocardial areas of the heart. Three rabbits died shortly after infusion of glycine 1.5% + ethanol 1%, the deaths being preceded by bradycardia and an irregular cardiac rhythm. This solution also lowered the intracellular potassium and chlorine content as shown by X-ray microanalysis of myocardial cells. Mannitol 3% + ethanol 1% produced the most favorable outcome in our evaluation, with the lowest scores for tissue swelling, while sorbitol 2% + mannitol 1% and normal saline took intermediate positions.

Animals↗
PubMed1995

Mortality among HIV-infected intravenous drug addicts in Stockholm in relation to methadone treatment.

The aim of the study was to estimate the mortality rate and evaluate the causes of death in all diagnosed HIV-positive IDUs in the Stockholm area, 1986-90, and to compare the risk of death of those who received methadone treatment with that of those never admitted to or discharged from the programme. Data were collected from the Swedish National Bacteriological Laboratory, the Methadone Maintenance Programme (MMTP) and the Department of Forensic Medicine, as well as from hospitals in the Stockholm region. In Sweden 90% of all IDUs are HIV-tested. Most deceased IDUs are examined forensically. This examination always includes HIV-testing. During the observation period, 472 HIV-infected IDUs were reported from the Stockholm area. Of these addicts 135 participated in the methadone maintenance programme for a shorter or longer time during the study period. Most of them had received the HIV-diagnosis more than 1 year before first entering the programme. Sixty-nine subjects died during the observation period. A majority, 52 persons, died from violence or poisoning. Seventeen died from somatic complications of drug abuse. Nine of them were diagnosed as suffering from AIDS. Eight of the deceased had participated in the MMTP. The relative risk of death from external violence and poisoning was 0.25 (95% confidence interval 0.1-1.0) when participants in the MMTP were compared with HIV-infected IDUs never attending the programme. When all causes of death are compared the relative risk was 0.8. Those patients discharged from the programme have a higher mortality rate than those who never participated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Brain weight and sudden infant death syndrome.

Increased brain weights have been reported in the literature to occur among infants who have died from sudden infant death syndrome, suggesting that cerebral edema might play a role in the cause of death among these children. We have compared brain weights from children between the ages of 1 week and 1 year, autopsied between 1980 and 1992. One group consisted of 125 victims of sudden infant death syndrome and the other of 38 children who had died with a diagnosis other than the sudden infant death syndrome. Brain weights from both groups exceeded the 50th percentile in previously published reference material. We were unable to show any significant differences between the groups in either the ratio between observed and expected brain weights or the ratio between brain weight and body weight. We conclude that there is no evidence for the notion that victims of sudden infant death syndrome have an increased brain weight. Other authors (in previous studies) may have overlooked the low overall weight at gestational age of prematurely born children while collecting data for reference levels. A revision of the figures seems to be necessary.

Anthropometry↗
PubMed1995

Effect of moderate ethanol intake on the heart: biochemical and morphological studies with isolated cardiomyocytes from rats fed a low-protein diet.

OBJECTIVE: It has been shown that chronic consumption of ethanol can impair myocardial function and result in morphological changes of the heart. The purpose of this work was to evaluate relations between changes in energy metabolism and changes of cell morphology. METHOD: Long-term effects of moderate ethanol consumption on the heart were examined in isolated cardiomyocytes from rats fed a pellet with low-protein content for 6 months. Digitonin treatment of the cardiomyocytes was used to separate mitochondrial and cytosolic fractions. RESULTS: A greater fraction of contracted myocytes was isolated from ethanol- and glucose-treated rats, than from rats fed only glucose and/or water as liquid supplement. There were changes of the ultrastructure of myocytes from ethanol and glucose-treated rats, which included mitochondrial degeneration, accumulation of fat droplets and depletion of the glycogen content. An elevated cytosolic level of nucleotides (ATP, ADP and NAD) and disappearance of magnesium from the mitochondrial fraction were observed in myocytes from rats fed ethanol and glucose. The release of adenosine was also found to be inhibited in these cells. CONCLUSIONS: Our results show that moderate ethanol consumption by rats during protein-restricted conditions produces subclinical changes of cardiomyocyte ultrastructure and alteration of cell morphology. Furthermore, the results indicate that changes of the energy homeostasis in myocytes and inhibition of sarcolemmal adenosine transport are early events that appear to precede the histological alterations.

Alcohol Drinking↗
PubMed1994

Nicotine and cotinine levels in pericardial fluid in victims of SIDS.

We have analyzed the levels of nicotine and cotinine in pericardial fluid in 24 consecutively autopsied cases of sudden unexpected death in infants aged one to six months. Our aim was to determine to what extent victims of sudden infant death may have been exposed to passive smoking near the time of death. Sixteen of the decreased infants were classified as SIDS at autopsy. Other contributing causes of death, predominantly infections, were found in eight cases. Eight infants (30%) had cotinine levels less than 2 ng, indicating that no significant exposure to nicotine had occurred near the time of death. Of the remaining 70%, five had been moderately exposed, seven markedly exposed and four heavily exposed (cotinine levels 2-10 ng, 10-50 ng and more than 50 ng, respectively). Since only 18% of Swedish women smoke after childbearing we conclude that nicotine exposure in infants who died suddenly was much higher than one would otherwise expect. It is hypothesized that high concentrations of nicotine and nicotine metabolites around the heart may affect cardiac function and thus play a role in the mechanisms causing SIDS or other categories of sudden unexpected death.

Cotinine↗
PubMed1992

HIV-1- prevalence among drug deaths in major cities of central and northern Europe.

Since 1985, a number of Institutes of Forensic Medicine in Germany have cooperated in a multicenter study, to provide a constant monitoring of HIV-1-prevalence among drug related deaths. In 1990/91, the Institutes in Copenhagen, Stockholm, Vienna and Zürich also participated in this study. HIV-1-prevalence is decreasing in the German cities, whereas the epidemiological development is not uniform in the other major cities. Regional differences are obvious. In 1991, the prevalence rates were as follows: Berlin 15% (n = 220), Hamburg 4% (n = 179), Frankfurt 17% (n = 167), Munich 9% (n = 136), Stockholm 10% (n = 79), Copenhagen 14% (n = 130), Vienna 20% (n = 56), and Zürich 23% (n = 84).

Acquired Immunodeficiency Syndrome↗
PubMed1992

Suicide related to human immunodeficiency virus infection in Stockholm.

During a 5-year period (July 1, 1985 to June 30, 1990), a systematic investigation of medicolegal autopsy cases with regard to the occurrence of human immunodeficiency virus (HIV) infection was carried out at the Department of Forensic Medicine in Stockholm, Sweden. Cases where a positive result was obtained from enzyme-linked immunosorbent assay and Western blotting were counted as HIV-positive (85 instances among 16,938 deaths, or 0.50%). Of these deaths, 21 (25%) were suicides. The number and proportion of suicides among HIV-positive homo- and bisexual males increased during the study period but remained unchanged for infected intravenous drug addicts. This increase of suicides among homo- and bisexual males could be related to the duration of the infection and to the manifestation of acquired immunodeficiency syndrome (AIDS) symptoms. Only 1 of the 21 suicides occurred in a hospital; 17 were committed in the homes of the deceased and 3 outdoors. Medicinal drug overdosage was the dominant choice of suicide method. Six of 12 homo- and bisexual males who committed suicide were of non-Swedish origin, i.e. immigrants, likely to have a less stable social network and thereby probably receiving less psychosocial support than the native population.

AIDS Dementia Complex↗
PubMed1991

Poisoning with sodium hypochlorite solution. Report of a fatal case, supplemented with an experimental and clinico-epidemiological study.

A case of fatal poisoning in a 1-year-old girl after ingestion of a household cleanser containing 4.5% sodium hypochlorite (Klorin) in an alkaline solution (pH 12.0) is reported. The forensic medical and toxicological investigations were supplemented by animal studies. These studies indicate that 5, 10, and 15 ml of Klorin/kg body wt given to rats is highly toxic, and that local tissue damage and secondary systemic involvement develops with a severity corresponding to the amount administered. The rats, all of which died, showed various degrees of degeneration and necrosis of the esophagoventricular mucosus membranes, changes analogous to those found at the autopsy of the child. A follow-up investigation of similar cases reported to the Swedish Poison Information Centre, during a limited time, was made to complete the picture.

Accidents↗
PubMed1990

Immunofluorescence demonstration of digoxin in human myocardial tissue and isolated rat cardiac myocytes with monoclonal antibodies.

The aim of the present investigation was to identify the morphological correlates of digoxin binding sites in human heart muscle tissue and isolated viable rat heart myocytes. Cardiac glycoside linked to myocardial cells was demonstrated by monoclonal digoxin specific antibody and by FITC-conjugated anti-mouse immunoglobin serum. This versatile immunofluorescence method can be used in diagnostic and experimental studies of cardiac glycoside binding.

Animals↗
PubMed1989

HIV-related deaths outside medical institutions in Stockholm.

During a 3-year period (August 1st, 1985 to July 31st, 1988) a systematic investigation of medico-legal autopsy cases with regard to the presence of antibodies for HIV-virus was carried out at the Department of Forensic Medicine in Stockholm, Sweden. Prior to autopsy, blood samples were taken from femoral or subclavian veins and were investigated by use of ELISA-screening and Western blotting test. During the first year of study, HIV infection was demonstrated in 11 out of 3464 deaths (0.32%), during the second year in 29 out of 3483 deaths (0.83%), and during the last year in 13 out of 3107 deaths (0.42%). It was shown that 48 out of the total of 53 HIV positive cases were previously registered, but information about the infection was available to the autopsist in only 27 cases. Drug addicts dominated 41 of 53 cases. There were only eight homo- and bisexual males, two non drug addict Central Africans and two persons who received blood transfusions. Eight of the 53 persons died of natural causes whereas 45 deaths were due to violence and drugs. The causes of death of the HIV positive drug addicts were compared to the causes of death of the HIV negative addicts. The HIV positive drug addicts tended to die suddenly in connection with the intravenous administration of heroin and at lower blood concentrations of morphine more often than the HIV-negative addicts. No increase in the suicide frequency was noted in drug addicts in Stockholm during the studied period.

Acquired Immunodeficiency Syndrome↗