Suitability of miRNA assessment in postmortem interval estimation.

OBJECTIVE: The aim of this review was to explore recent pieces of evidence focused on the use of miRNAs for PMI estimation both in humans and animal experiments, with particular interest on the best miRNAs to use as reference/target markers in different tissues or biological fluids. MiRNAs are innovative biomarkers used in clinical and research field; they appear very attractive, being introduced in forensic research scenarios even for PMI estimation. MATERIALS AND METHODS: Data from PubMed and Scopus were analyzed from January 2013 to August 2020. Based on inclusion/exclusion criteria, high-quality articles have been selected to become the subject of this review. RESULTS: A total of 737 papers were found but, after titles/abstracts screening for inclusion criteria and a full-text careful selection, 33 papers were deeply studied. After the exclusion of 19 papers, 15 articles remained. Eight papers dealt with animals (mice/rats), two both with animals and humans (for method validation previously built), while 5 exclusively with humans. Myocardium (6/15) and brain (6/15) were the most studied tissues, respectively in mice/rats and humans. PMI considered was up to 7.5 days in mouse studies and less than 3 days in human models. CONCLUSIONS: Because of their significant stability in both early and long PMI, miRNAs are the cleverest reference markers to be used. Temperature and environmental conditions influence mostly mRNA, while miRNAs are less susceptible to them. The best miRNA to choose depends on its tissue specificity, i.e., miR-9 and miR-125 in brain or miR-1 and miR-133 in skeletal muscle/heart.

SARS-CoV-2 identification in lungs, heart and kidney specimens by transmission and scanning electron microscopy.

From two COVID-19-related deaths, samples of lung, heart and kidney were collected and processed for Transmission and Scanning Electron Microscopy (TEM and SEM) with the aim of identifying the virus. Virions of SARS-CoV-2 were found in all tissues by TEM and SEM, corroborating the hypothesis that the virus enters the cells of different organs. This is the first report identifying SARS-CoV-2 in different human tissues by TEM and SEM.

Flutamide-induced hepatotoxicity: ethical and scientific issues.

OBJECTIVE: Flutamide (FLU) is a non-steroidal antiandrogen drug approved for the treatment of advanced prostate cancer. While this indication limits the use to male patients, FLU is widely prescribed to women, off-label, for the treatment of polycystic ovary syndrome (POCS) related hirsutism and acne. According to the literature, its assumption is associated with a higher incidence of adverse events in women than in male patients. MATERIALS AND METHODS: A literature search was conducted in main databases targeting unwilling FLU effects in hepatic and reproductive function. References in the selected paper were also considered as an additional source of data. Human- and animal-based studies were separately considered. RESULTS: Twenty-three human-based studies were evaluated: ten were case reports, six were retrospective studies, four were prospective, two were surveillance studies, while the last was an observational study. Nine animal-based studies were also evaluated. CONCLUSIONS: Scientific contributions highlight that FLU is responsible for specific hepatotoxic profiles in the female gender. From the ethical point of view, off-label prescribing of FLU in women is not only substantially unlawful, but also, without major safeguards being granted, a potential source of liability for prescribers.

Analysis of immunohistochemical expression of inducible nitric oxide synthase for the evaluation of agonal time in forensic medicine.

Although establishing agony is crucial in forensic practice, the identification of specific signs indicative of a detailed duration of agony is however not of immediate execution. Nitric oxide (NO) is the most important messenger molecule in the modulation of vascular tone and it is produced during stress conditions by inducible nitric oxide synthase (iNOS), as occurs during agony. The aim of this study was to investigate the relationship between immunohistochemical expression of iNOS, and agonal time (T), defined as the interval between the onset of a hypoxic-ischemic injury and the death. INOS expression was evaluated by measuring the average of signal intensity (SI) from cytoplasm of 300 smooth muscle cells of sample of renal artery, performed by ImageJ software: high values of SI correspond to a low enzyme expression and vice versa. We aimed also to check if gender, age, type of death (violent or natural death), post mortem interval, and storage in cold chamber influenced SI. We assessed 50 autopsied cases, of which 28 violent and 22 natural deaths, with a well-known T in a range between 1 and 631 min. Statistical analysis was performed to estimate the relationship between SI and the other variables. Results pointed out that only SI is related to T, and since data showed a bi-phase relationship between T and SI, we used a piecewise regression method for estimation of T as function of SI. The transition from the first to the second phase takes place at SI = 117.5 which corresponds to a T of 29.5 min. In conclusion, the study demonstrates that iNOS is a good marker for estimating T and the final regression model can be used in many forensic activities.

Effects of ketamine on psychomotor, sensory and cognitive functions relevant for driving ability.

Ketamine is a dissociative anesthetic. The misuse of ketamine as a recreational drug has increased over the last decade, especially in rave parties or clubs. Short-term ketamine pilot protocols have been undertaken for treatment-resistant depressive clients. In this study, we review and comment on the evidence relating to the potential of ketamine as a causative/contributory factor in traffic accidents. To determine the causal role of ketamine in traffic accidents, a literature search on the psychomotor, cognitive, visual and perceptual functions related to safe driving was conducted. Furthermore, to interpret related data better, an overview of ketamine and its congeners' clinical pharmacology issues, recreational psychoactive effects, and identification in biological specimens is also provided.

GHEP-ISFG proficiency test 2011: Paper challenge on evaluation of mitochondrial DNA results.

The GHEP-ISFG Working Group performed a collaborative exercise to monitor the current practice of mitochondrial (mt)DNA reporting. The participating laboratories were invited to evaluate a hypothetical case example and assess the statistical significance of a match between the haplotypes of a case (hair) sample and a suspect. A total of 31 forensic laboratories participated of which all but one used the EMPOP database. Nevertheless, we observed a tenfold range of reported LR values (32-333.4), which was mainly due to the selection of different reference datasets in EMPOP but also due to different applied formulae. The results suggest the need for more standardization as well as additional research to harmonize the reporting of mtDNA evidence.

Histopathological markers for the diagnosis of anaphylactic death.

The postmortem diagnosis of anaphylactic death may be frustrating when victims are not hospital patients, even more so when they are recovered dead. The frequent lack of specific morphological findings in such cases means that diagnosis by the forensic pathologist must rely solely on exclusion criteria or circumstantial evidence. However, a diagnostic approach based on case history, analysis of circumstances, available clinical and necropsy findings, as well as toxicology, histopathology and biohumoral data, often allows demonstration of the cause of death. Some useful reflections on microscopic morphological data have come from two recent cases, where thorough data collection provided a reasonably certain diagnosis of anaphylactic death and systemic inflammatory response syndrome-related cardiac arrest, respectively. In both cases tissue histopathology proved crucial, since histochemical (GIEMSA) and immunohistochemical analysis (CD117 and tryptase) documented a large number of mast cells in tissues, particularly the laryngeal wall, and a discrepancy between cells positive for GIEMSA and tryptase and those positive for CD117. Staining for CD117 was also detected in cells with dendrite morphology and in a subpopulation of small lymphocytes with incised nuclei. The morphological findings of these cases are discussed, especially those obtained with immunohistochemistry, and the need for the latter data to be interpreted by experienced medical staff in the framework of a thorough analysis of all the data collected is highlighted.

Multiplex mtDNA coding region SNP assays for molecular dissection of haplogroups U/K and J/T.

Mitochondrial DNA (mtDNA) U/K and J/T are sister haplogroups within the superhaplogroup R. They are both common in Europe, with a combined overall frequency similar to the one reported for H, the most common European haplogroup (40-50%). In this study, we selected 159 Italian subjects, already ascribed to U/K and J/T by RFLP typing, and assigned each mtDNA to specific clades/subclades by investigating at least one diagnostic coding region SNP. For each sister haplogroup, one multiplex PCR and one SNaPshot minisequencing reaction were set up targeting 16 U/K and 7 J/T coding region SNPs. Each mtDNA sample was clearly assigned to a specific subclade, which could be further subdivided into several minor sub-branches according to peculiar HVS I/II motifs. Such a molecular dissection of haplogroups U/K and J/T could be extremely useful to reduce the overall analysis time and labor intensive sequencing procedures in high volume forensic casework, for example when it is important to rapidly exclude samples in order to restrict the number of suspects.

Engraftment capacity of mesenchymal cells following hematopoietic stem cell transplantation in patients receiving reduced-intensity conditioning regimen.

The engraftment ability of mesenchymal cells was investigated in 26 patients receiving allogeneic transplantation from HLA-identical siblings with reduced-intensity conditioning (RIC). The stem cell source was bone marrow (BM) in eight patients and G-CSF-mobilized peripheral blood hematopoietic cells in 18 cases. A total of 32 patients engrafted very quickly and the chimerism evaluation (both on myeloid and on lymphoid subsets) showed that they were full donor by day 60. At the time of the study they were in complete hematological remission and displayed a full donor hematopoiesis. Two patients showed early disease progression while one did not engraft. Forty-eight out-marrow samples harvested from the 26 patients generated a marrow stromal layer adequate for the chimerism evaluation. Monocyte-macrophage contamination of marrow stromal layers was always reduced below 2% by repeated trypsinizations and treatment with the leucyl-leucine (leu-leu) methyl ester. The chimerism evaluation was performed by PCR analysis of STRs microsatellites and the amelogenin locus, by using capillary electrophoresis (CE) and by FISH analysis in case of the sex mismatch. In eight patients, a partial donor origin of stromal cells was shown (7-86% cells of donor). The source of hematopoietic cells was BM in three patients and mobilized peripheral blood in the other five.

Subtyping mtDNA haplogroup H by SNaPshot minisequencing and its application in forensic individual identification.

Sequence variation of the hypervariable segments (HVS) I/II of mitochondrial DNA (mtDNA) and the haplogroup affiliation were determined in a sample of 271 Italian subjects. This analysis showed that 42% of the individuals could be ascribed to H, the most frequent haplogroup in European Caucasian populations. This fraction was then screened for specific single nucleotide polymorphisms located in the coding region to identify H subclades H1-H15. We set up two multiplex polymerase chain reactions and specific SNaPshot assays to investigate the frequency distribution of these subgroups in our population sample and to examine their usefulness in discriminating among commonly shared HVS I/II sequences. This allowed the assignment of a large portion of the mtDNAs ( approximately 70%) to specific subhaplogroups, with H1 and H5 being the most represented. About two-thirds of the individuals sharing common HVS I/II sequences were subdivided and ascribed to specific H subhaplogroups with a significant reduction of the frequencies of the most common mtDNA haplotypes. Haplogroup H subtyping could thus be extremely useful in forensic identification when many samples have to be analysed and compared, avoiding excessive time-consuming and labor-intensive sequencing analysis.

Polymorphism of the mitochondrial DNA control region in Italians.

Mitochondrial DNA sequences of the hypervariable regions HVI and HVII were analysed in 83 Caucasians living in central Italy to expand the database for forensic identification purposes, and 75 different haplotypes resulting from 62 polymorphic positions in HVI and 44 in HVII were observed. The most frequent haplotype (263G, 309.1C, 315.1C) was shared by 7 individuals, 2 haplotypes were shared by 2 individuals, and 72 were unique. The genetic diversity was found to be 0.99 and the random match probability 1.9%. A condition of sequence heteroplasmy was found in only one case at nt 16311, whereas a length heteroplasmy was found in the homopolymeric stretch of cytosines 303-315. Our results indicate that in direct sequencing beyond the poly-cytosine stretch, the overlap is due to length heteroplasmy, whereas the blurred signal occurs when the stretch is composed of more than 10 cytosines.

Effects of single dose of gamma-hydroxybutyric acid and lorazepam on psychomotor performance and subjective feelings in healthy volunteers.

OBJECTIVE: This study investigated the possible effects of gamma-hydroxybutyric acid (GHB) on human psychomotor performance and subjective feelings important for the safety of skilled performance. METHODS: Twelve healthy volunteers, six males and six females, aged 22-36 years, participated as subjects. Drugs and placebo were administered according to a single-dose, double-blind, balanced, four-way, crossover design. Treatments were separated by a wash-out period of 1 week and consisted of placebo, lorazepam 0.03 mg x kg(-1), GHB 12.5 mg x kg(-1) and GHB 25 mg x kg(-1). Subjects' psychomotor performance was assessed at baseline and at 15, 60, 120 and 180 min after treatment. Mood was assessed using 16 visual analogue scales, before treatment and 120 min later. Psychomotor performance was measured using the following tests: Critical Flicker Fusion. Response Competition Test, Critical Tracking Task, Choice Reaction Time and Visual Vigilance Task. RESULTS: GHB at both doses had no effects on attention, vigilance, alertness, short-term memory or psychomotor co-ordination (delta-placebo, P > 0.05); calmness increased with the lower dose and contentedness decreased significantly at both doses (delta-baseline, P < 0.05); adverse effects were limited to slight subjective feelings of dizziness and dullness, which disappeared 30-60 min after administration of the dose. Lorazepam caused impairment of psychometric functions. CONCLUSION: After single therapeutic doses, GHB does not induce changes in psychomotor performance and therefore the drug does not influence the ability to drive or work. However, repeated reports of the abuse potential of GHB and its usefulness in treating ethyl alcohol addiction indicate that it may play an "agonist-like" role, which means that it should only used under close medical supervision.

Allele typing of short tandem repeats by capillary electrophoresis.

Capillary electrophoresis with laser-induced fluorescence was applied to the analysis of six STRs and the amelogenin sex test with the purpose of verifying accuracy and precision of the sizing method with the GS500 internal standard. Sequenced dye-labeled, PCR-amplified alleles from amelogenin, HumVWA31, HumTH01, HumF13A01, HumFIBRA, D21S11 and HumCSF1PO loci were run several times on the same capillary and on multiple capillaries and the offset of computer-measured fragment sizes from the expected molecular weights was calculated and analysed. All loci except D21S11 showed a poor degree of accuracy. Precision results from run-to-run and day-to-day injections displayed a maximum standard deviation (SD) > 0.15 nt for HumVWA31, HumF13A01, D21S11 and HumFIBRA, although the maximum range of calculated sizes in multiple runs was lower than 1 basepair. No variation in precision was observed according to the quality of the DNA template. Allele typing by comparison with allelic ladders for each locus is recommended.

Polymorphism and sequence variations of the HumCD4 pentameric microsatellite in an Italian population sample.

A sample of 265 subjects from central Italy was analyzed at the HumCD4 locus by polymerase-chain-reaction (PCR). Phenotypes were identified by comparison with a sequenced ladder, after high-resolution horizontal polyacrylamide gel electrophoresis (PAGE) followed by silver staining. A set of representative alleles was sequenced by Taq-cycle-sequencing with dye terminator labeling and capillary gel electrophoresis strategies. Eight common alleles--5, 6, 7, 8, 9, 10, 11, 12--and a rare larger 14, never before described in Caucasians, were found. Allele and genotype frequencies were similar to those described in former studies on Caucasians, with a prevalency of alleles number 5, 6, 10. Sequence analysis showed that the polymorphism is due to a pentameric TTTTC basic motif, tandemly repeated, and that from allele number 10 onwards the fourth repeat presents a T to C translation (CTTTC). Instead, allele number 9 may exist in two forms, because 75% of alleles examined in this study presented the CTTTC motif at the fourth position, while the remaining 25% had the basic repeat structure.

Polymerase chain reaction typing of D21S11 short tandem repeat polymorphism by capillary electrophoresis. Allele frequencies and sequencing data in a population sample from central Italy.

Blood samples were collected from 100 individuals living in Central Italy and analysed for STR locus D21S11 by capillary electrophoresis on an ABI Prism 310 genetic analyzer. For fragment sizing, PCR amplification products, obtained using a 6-FAM 5'-labeled reverse primer and an unlabeled forward primer, were run with an internal size standard labeled with TAMRA dye and typed using the local reciprocal method. An allele ladder consisting of a mix of sequenced amplified products was also prepared. An Italian population database was established. No deviation from Hardy-Weinberg equilibrium was observed. The result of statistical analysis were highly informative (PD = 0.94; mean exclusion change = 0.66). DNA sequencing was performed on a set of representative alleles by Taq cycle sequencing using dye terminator labeling chemistry. A new structural variant was found.

PCR analysis of the STR HUMF13A01 in a population sample of central Italy.

A population genetic study was carried out on an Italian sample of Central Italy (n = 159) using the short tandem repeat (STR) system HUMF13A01. After vertical electrophoresis in denaturing polyacrylamide gel, 11 alleles were found. No deviation from the Hardy-Weinberg equilibrium were observed. The power of discrimination (PD) was 0.91 and the chance of exclusion was 0.59. The allelic comparison with previous Italian population studies showed no significant difference.

Opiate-related death: morphometric study of neurons from the dorsal motor nucleus of the vagus nerve.

The aim of this work is to verify the presence of objectively observable morphological alterations caused by the direct action of opiates on brain structures controlling respiration in cases of drug-related deaths. A computer-assisted morphometric study was carried out on the Dorsal Motor Nucleus of the Vagus Nerve (DMNV) in seven subjects (four of whom died of drug overdose, and 3 controls). Serial sections 10-15 microns thick were stained according to Nissl. The sections were then examined under the optical microscope and 200 fields per subject were digitalized. The resulting images, regarding at least 700 neurons per subject were segmented using a semi-automatic procedure and analysed by the Optilab software. The data obtained were subjected to cluster analysis to identify the neuron classes in the DMNV. Each subject was characterized with a vector of percentages indicating the fraction of neurons falling in each of these classes. Discriminant analysis was then applied to verify to what extent the variables discriminated between the two populations. Results indicated that: the statistical methods adopted have a good power of discrimination; in subjects who died of opiate overdose, the neurons are distributed to a greater extent in classes composed of smaller neurons than in controls.

Italian population data on the loci LDLR, GYPA, HBGG, D7S8 and GC.

Allele and genotype frequencies for the five loci LDLR, GYPA, HBGG, D7S8 and GC were determined for 374 unrelated Italians using a multiplex PCR-amplification and typing commercial kit. The distribution of the genotype frequencies showed no deviations from Hardy-Weinberg expectations. The combined power of discrimination and chance of exclusion for all five loci were 0.999 and 0.702, respectively. A test for homogeneity was performed and no significant differences were observed among the Caucasian population samples.