Forensic species identification: practical guide for animal and plant DNA analysis.

The importance of non-human DNA in the forensic field has increased greatly in recent years, together with the type of applications. The molecular species identification of animal and botanical material may be crucial both for wildlife trafficking and crime scene investigation. However, especially for forensic botany, several challenges slow down the implementation of the discipline in the routine.Although the importance of molecular analysis of animal origin samples is widely recognized and the same value is acknowledged to the botanical counterpart, the latter does not find the same degree of application.The availability of molecular methods, especially useful in cases where the material is fragmented, scarce or spoiled preventing the morphological identification, is not well known. This work is intended to reaffirm the relevance of non-human forensic genetics (NHFG), highlighting differences, benefits and pitfalls of the current most common molecular analysis workflow for animal and botanical samples, giving a practical guide. A flowchart describing the analysis paths, divided in three major working areas (inspection and sampling, molecular analysis, data processing and interpretation), is provided. More real casework examples of the utility of non-human evidence in forensic investigations should be shared by the scientific community, especially for plants. Moreover, concrete efforts to encourage initiatives in order to promote quality and standardization in the NHFG field are also needed.

Unexpected intrauterine fetal death in parvovirus B19 fetal infection.

Parvovirus B19 infection during pregnancy can be transmitted to the fetus through the placenta. The consequences for the health of the fetus are very variable and can be very serious. They include intrauterine fetal death (IUFD) and miscarriage, which can lead to medico-forensic questions. For the most part, cases of IUFD take place during the second trimester of gestation and present an anatomopathologic picture characteristic of fetal infection with hydrops, placental edema, serous effusion, and erythroblastosis with nuclear inclusions. Endocardial fibroelastosis, medullar and thymic hypoplasia, and hepatic hemosiderosis are frequently present. In the third trimester, the cases are less frequent, not accompanied by hydrops, and can depend more on placental compromise than on direct infection of the fetus. We present 5 cases of IUFD resulting from parvovirus B19 and we discuss the pathogenetic and anatomopathologic aspects and obstetric liability. In 4 cases, the IUFD took place suddenly, in the absence of symptoms, in women who had not previously shown any symptom of the viral infection. In one case, the patient was hospitalized following an ultrasound diagnosis of fetal hydrops and IUFD took place 5 days after admission. Of these cases 3 were verified in the second trimester and 2 in the third trimester. Only the cases of the second trimester and one of the 2 cases of the third trimester presented the characteristic aspects of fetal infection. The other case of third trimester was characterized by placental involvement.

Spontaneous umbilical cord hematoma: an unusual cause of fetal mortality: a report of 3 cases and review of the literature.

Spontaneous hematoma of the umbilical cord represents a rare cause of fetal morbidity and mortality and the outcome is poor in half of the cases. There are many risk factors, such as infections, morphologic anomalies, alterations of the vessel walls, prolapses, twisting and traction of the cord, but in many cases the causes remain unknown. We present 3 cases of umbilical cord hematoma which took place at the end of the pregnancy and were followed by perinatal death of the fetus. In the 3 cases, which were autopsied including macroscopical and histopathologic examination of the placenta and the umbilical cord, a cordonal pathology was present; in all cases, there were alterations of the vascular wall, and in the third case inflammatory vasculopathy was found. In all 3 cases, the cause of death was attributed to acute anoxia due to the cordonal hematoma.

The role of ethyl glucuronide in supporting medico-legal investigations: Analysis of this biomarker in different postmortem specimens from 21 selected autopsy cases.

Ethanol determination in postmortem blood is one of the most frequently requested analyses in legal medicine and forensic toxicology. Ethyl glucuronide is a non-oxidative ethanol metabolite. It is also a useful marker of ante-mortem alcohol ingestion when ethanol itself has been completely eliminated from the body and could be considered in autopsy cases to obtain more reliable indications. The aim of the present study was to investigate the ethyl glucuronide distribution in postmortem specimens from autopsy cases found to be positive for ethanol. We presented 21 autopsy cases in which central blood, peripheral blood and liver samples were available. Specimens were analyzed for ethyl glucuronide by liquid chromatography tandem mass spectrometry; we also recorded postmortem interval, case history, cause of death, use of drugs, metabolic disorders if present, putrefaction if present, history of ethanol abuse and information about ethanol intake before death. Our aim was to evaluate and to compare the ethyl glucuronide levels in different matrices taken from the same subject in order to provide a better understanding of the interpretation of postmortem ethyl glucuronide concentrations.

Lateral saccular laryngeal cyst and unexpected asphyxial death.

We present the case of a 41-year-old man with a herniated saccular laryngeal cyst in the left cervical region who died unexpectedly at home from acute asphyxia. A few days before death the patient complained an obvious palpable swelling on the left side of the neck. The autopsy showed an oval-shaped mass originating on the wall of the larynx and herniating into the extralaryngeal region. The critical reduction of the laryngeal lumen originated from an intense oedema of the laryngeal mucosa above the cyst, concurrent with an inflammatory process of the cystic wall, with probable associated glottis laryngospasm mediated by the superior laryngeal nerve. The rapid evolution of oedema was favoured by the extreme relaxation of the connective tissue of the laryngeal mucosa in the supraglottic and aryepiglottic regions which explains the sudden death. The case is useful for delineating the problems related to the possible evolution of laryngeal cysts, the mechanisms of asphyxial complications, the pathological diagnosis and the medico-forensic aspects.