Supravital expression of heat-shock proteins

State-of-the-Art on Wound Vitality Evaluation: A Systematic Review

The vitality demonstration refers to determining if an injury has been caused ante- or post-mortem, while wound age means to evaluate how long a subject has survived after the infliction of an injury. Histology alone is not enough to prove the vitality of a lesion. Recently, immunohistochemistry, biochemistry, and molecular biology have been introduced in the field of lesions vitality and age demonstration. The study was conducted according to the preferred reporting items for systematic review (PRISMA) protocol. The search terms were "wound", "lesion", "vitality", "evaluation", "immunohistochemistry", "proteins", "electrolytes", "mRNAs", and "miRNAs" in the title, abstract, and keywords. This evaluation left 137 scientific papers. This review aimed to collect all the knowledge on vital wound demonstration and provide a temporal distribution of the methods currently available, in order to determine the age of lesions, thus helping forensic pathologists in finding a way through the tangled jungle of wound vitality evaluation.

Renal expression of Hsp27, 60, and 70 in cases of fatal hypothermia

Macromorphological findings can be missing in cases of fatal hypothermia when the agonal period is very short because of a large difference between environmental and core body temperatures. Expression of heat shock proteins (Hsps) increases under endogenous and exogenous cellular stresses such as thermal stress. These stress proteins can be revealed by immunohistochemical staining. Forty-five cases of death due to hypothermia and a control group of 100 deaths without any antemortem thermal stress were examined for Hsp27, 60, and 70 expression in renal tissue because renal tissue is sensitive to cellular stress. The results revealed no significant difference between Hsp27, 60, and 70 expression in both groups (28.8% positive staining in the study group and 19.0% positive staining in the control group), which is contradictory to a previous study on expression of Hsp70 in renal tissue in cases of fatal hypothermia. Hence, it is currently unclear whether immunohistochemical staining of Hsps supports a morphological diagnosis of fatal hypothermia.

Role of Heat Shock Proteins (HSP70 and HSP90) in Viral Infection

Heat shock proteins (HSPs) are a large group of chaperones found in most eukaryotes and bacteria. They are responsible for the correct protein folding, protection of the cell against stressors, presenting immune and inflammatory cytokines; furthermore, they are important factors in regulating cell differentiation, survival and death. Although the biological function of HSPs is to maintain cell homeostasis, some of them can be used by viruses both to fold their proteins and increase the chances of survival in unfavorable host conditions. Folding viral proteins as well as replicating many different viruses are carried out by, among others, proteins from the HSP70 and HSP90 families. In some cases, the HSP70 family proteins directly interact with viral polymerase to enhance viral replication or they can facilitate the formation of a viral replication complex and/or maintain the stability of complex proteins. It is known that HSP90 is important for the expression of viral genes at both the transcriptional and the translational levels. Both of these HSPs can form a complex with HSP90 and, consequently, facilitate the entry of the virus into the cell. Current studies have shown the biological significance of HSPs in the course of infection SARS-CoV-2. A comprehensive understanding of chaperone use during viral infection will provide new insight into viral replication mechanisms and therapeutic potential. The aim of this study is to describe the molecular basis of HSP70 and HSP90 participation in some viral infections and the potential use of these proteins in antiviral therapy.

Death in the sauna-vitality markers for heat exposure

In sauna-associated deaths, the vitality of heat exposure is of great importance. Two case reports address this. First, we present the case of a 77-year-old man who was found dead in the sauna of his family home. When found, the sauna door was closed, and the sauna indicated a temperature of 78 °C. The body had already begun to decay and was partially mummified when it was found. In the other case, a 73-year-old woman was found dead in the sauna by her husband. In this case, the sauna door was also closed. The sauna was still in operation at a temperature of approximately 70 °C. Epidermal detachments were found. In both autopsies and their follow-up examinations, there were no indications of a cause of death competing with heat shock. The expression of heat shock proteins in kidneys and lungs and the expression of aquaporin 3 in skin were investigated to detect pre-mortal temperature influences.

Expression of HSP70 family mRNAs in albino northern snakehead, Channa argus: Response to extreme temperature stress and bacterial infection

The wild albino northern snakehead, Channa argus, has only been found in Jialing Rivers System of China so far. It is easy to be affected by the environmental factors such as temperature changes and bacterial infection, thus causing a huge economic loss. Therefore, this study cloned a 2,213 bp cDNA that encodes a protein of heat shock protein 70 (CaHSP70), which has an open reading frame (ORF) that encodes 639 amino acids and the corresponding polypeptides of 70.50 kDa. And the oretical isoelectric point (pI) of CaHSP70 is 5.79. Additionally, we also cloned a cDNA for heat shock cognate protein 70 (CaHSC70) with a total length of 2,300 bp. And the ORF of CaHSC70 encodes 648 amino acids and 71.18 kDa peptides. The pI of CaHSC70 is 5.22. Moreover, the cDNA length of stress-70 protein mitochondrial (CaHSPA9) is 2,944 bp with an ORF that encodes 679 amino acids, polypeptides of 73.74 kDa, and a pI of 6.68. The quantitative real-time PCR (qRT-PCR) analysis showed that the mRNA expression levels of CaHSP70, CaHSC70, and CaHSPA9 genes were tissue-specific in the control groups. After the heat shock at 37 °C, the mRNA expression levels of CaHSP70 were extremely significantly upregulated in the kidney, liver, spleen, and brain tissues, while fewer mRNA expression levels of CaHSC70 and CaHSPA9 showed a relatively induction in these tissues. In contrast, after the cold shock at 8.5 °C, fewer mRNA expression levels of CaHSP70, CaHSC70, and CaHSPA9 showed the changes of expression in all the tissues, compared to heat shock. In addition, CaHSP70, CaHSC70, and CaHSPA9 mRNA expression levels showed an overall trend of first upregulating and then falling after Edwardsiella tarda (strain No. DL1,476) challenge. In conclusion, this study demonstrated that temperature had a great effect on the mRNA expression levels of CaHSP70, CaHSC70, and CaHSPA9, and the mRNA expression levels of these three genes were also sensitive to pathogen infection, especially CaHSP70 in the albino C. argus.

Fire exposure after lethal hypothermia

A 49-year-old woman was found dead in her apartment after a fire began in her building. During the forensic autopsy, 3rd to 4th degree burns were found on the woman's body, but there were no indications that she was alive when the fire started. Interestingly, hemorrhagic gastric mucosa erosions, as well as bloody contents in the esophagus, stomach, and intestines, were observed. However, the source of the bleeding could not be found. The cause of death was therefore determined to be hypothermia with postmortem fire exposure. The cause of the hypothermia could possibly have been high internal blood loss. The organs showed early signs of putrefaction. It was theorized that the woman had not died immediately before the fire began, but rather a few days before. Examination of heat shock proteins (HSPs) to evaluate premortem thermal influences did not reveal HSP 27, 60, or 70 expression in renal tissue, possibly because of the putrefaction. However, Sudan staining of this tissue revealed a fatty degeneration of renal tubular cells. Opposing temperature influences, as in this case, are rather rare and require thorough investigations.

Suicidal strangulation with a lashing belt

Ligature strangulation causes death due to neck compression without suspension. However, suicidal ligature strangulation is rare. The suicide of a 32-year-old man is presented. After a dispute, the man was found outdoors with a lashing belt around his neck which had been pulled tight with a ratchet. Conjunctival petechiae were found, but hemorrhages in the soft tissues were not observed. The hyoid bone and larynx did not show fractures or hemorrhage. Other injuries as well as signs of defence were not observed. The differentiation between homicidal and suicidal ligature strangulation can be difficult and requires careful investigation and collaboration by police and forensic pathologists.

Vital reactions - An updated overview

The question whether an injury was sustained during life or not is one of the most important subjects in forensic medicine. Therefore, vital reactions have been a main research topic in forensic medicine for a long period and many renowned forensic pathologists have devoted important papers to this field. The research area ranges from macroscopically visible organ reactions, over tissue alterations (enzyme histochemistry, later on immunohistochemistry with a wide range of enzymes and other analytes, molecular pathology) to biochemical responses to injury. Especially in the field of immunohistochemistry and molecular pathology much progress has been achieved in the last years (e.g. heat-shock-proteins or positive aquaporine3-staining in mechanical skin trauma). Furthermore, 20 years after its implementation postmortem imaging also contributes to the detection and visualization of vital signs. The aim of the present review is to provide an update on forensically relevant vital signs/vital reactions. Systemic vital reactions especially of the circulatory and respiratory system as well as local vital reactions will be addressed. Vital reactions of different organ systems will be discussed in detail regarding pathogenesis and possible postmortem evolution. Current research on immunohistochemically detectable vital reactions (heat-shock-protein expression, aquaporine3-staining in mechanical trauma of the skin) will be addressed as well as biochemical vital reactions (agonochemical stress reaction, myoglobine in electrocution death, hypoxanthine as marker of hypoxia).