Archaeological occurrences and historical review of the human amoeba,Entamoeba histolytica,over the past 6000 years

Understanding parasite history and the evolution of host/parasite relationships is one of the most important aspects of paleoparasitology. Within the framework of this research topic, this paper focuses on the human pathogenic amoeba, Entamoeba histolytica. The compilation of all the available archaeological data concerning this parasite leads to a first glimpse of the history of this parasite of current medical importance. Paleoparasitological investigation into this parasite uses immunological techniques and shows that the modern strain of E. histolytica has been present in Western Europe since at least the Neolithic period (3700 years BCE), and could have originated in the Old World. The appearance of the modern amoeba strain in the pre-Columbian Americas and the Middle East around the 12th century CE gives rise to hypotheses as to how human migrations (Atlantic or Pacific routes) contributed to the diffusion of this pathogen, resulting in its current distribution. This compilation proves that parasites are valuable proxies for studying past human and animal migrations, and should be given more consideration in the future.     

Association of low-activity MAOA allelic variants with violent crime in incarcerated offenders

The main enzyme for serotonin degradation, monoamine oxidase (MAO) A, has recently emerged as a key biological factor in the predisposition to impulsive aggression. Male carriers of low-activity variants of the main functional polymorphism of the MAOA gene (MAOA-uVNTR) have been shown to exhibit a greater proclivity to engage in violent acts. Thus, we hypothesized that low-activity MAOA-uVNTR alleles may be associated with a higher risk for criminal violence among male offenders. To test this possibility, we analyzed the MAOA-uVNTR variants of violent (n = 49) and non-violent (n = 40) male Caucasian and African-American convicts in a correctional facility. All participants were also tested with the Childhood Trauma Questionnaire (CTQ), Barratt Impulsivity Scale (BIS-11) and Buss-Perry Aggression Questionnaire (BPAQ) to assess their levels of childhood trauma exposure, impulsivity and aggression, respectively. Our results revealed a robust (P < 0.0001) association between low-activity MAOA-uVNTR alleles and violent crime. This association was replicated in the group of Caucasian violent offenders (P < 0.01), but reached only a marginal trend (P = 0.08) in their African American counterparts. While violent crime charges were not associated with CTQ, BIS-11 and BPAQ scores, carriers of low-activity alleles exhibited a mild, yet significant (P < 0.05) increase in BIS-11 total and attentional-impulsiveness scores. In summary, these findings support the role of MAOA gene as a prominent genetic determinant for criminal violence. Further studies are required to confirm these results in larger samples of inmates and evaluate potential interactions between MAOA alleles and environmental vulnerability factors.     

Genetic polymorphisms of twelve X-STRs of the investigator Argus X-12 kit and additional six X-STR centromere region loci in an Egyptian population sample

Recently, many researchers have focused on analysis of different X-chromosomal STRs as they bear the potential to efficiently complement the analysis of autosomal and Y-chromosomal STRs in solving special complex kinship deficiency cases. In the current study we examined a sample of 250 unrelated Egyptian males with the Investigator Argus X-12 kit (Qiagen GmbH, Hilden, Germany) which detects 12 X-STR markers distributed over the entire X-chromosome as four closely linked clusters. Microvariant off ladder alleles as well as null alleles have been detected in some loci. Furthermore, discordant results were observed between the Investigator Argus X-12 and the Mentype^® Argus X-8 kits (Biotype AG, Dresden, Germany). New primers were designed for loci DXS10101, DXS10146 and DXS10148 to correct the allele drop outs observed in these loci with the Investigator Argus X-12 kit. Additionally, DNA sequence analysis revealed the polymorphisms responsible for the allele drop outs. Furthermore, six additional X-STRs (DXS10161, DXS10159, DXS10162, DXS10163, DXS10164 and DXS10165) located in the centromere region at Xp11.21–Xq11.1 were examined in a single multiplex reaction. Allele and haplotype frequencies as well as different forensic statistical parameters of the 18 X-STR loci tested indicated that they are highly informative in different forensic applications in the Egyptian population. However, some modifications still need to be performed on the Investigator Argus X-12 kit before its use in forensic casework is validated.     

Multi-tissue DNA methylation age: Molecular relationships and perspectives for advancing biomarker utility

The multi-tissue DNA methylation estimator of chronological age (DNAm-age) has been associated with a wide range of exposures and health outcomes. Still, it is unclear how DNAm-age can have such broad relationships and how it can be best utilized as a biomarker. Understanding DNAm-age’s molecular relationships is a promising approach to address this critical knowledge gap. In this review, we discuss the existing literature regarding DNAm-age’s molecular relationships in six major categories: animal model systems, cancer processes, cellular aging processes, immune system processes, metabolic processes, and nucleic acid processes. We also present perspectives regarding the future of DNAm-age research, including the need to translate a greater number of ongoing research efforts to experimental and animal model systems.     

Utilising allelic dropout probabilities estimated by logistic regression in casework

Some advanced methods for DNA profile interpretation require a probability for the event of dropout. Methods have been suggested based on logistic regression. Two of these respectively use a proxy for template that is constant across loci and one that is modelled using an exponential curve. Both of these methods allow different modelling constants from each locus. A variant of the model using an exponential curve is discussed. This variant constrains the constants to be the same for every locus. We test these two methods and the variant by developing the constants (training) on one set of data and testing them on another. This mimics the likely use in casework. We find that the new variant appears to be the most useful in that it performs better than the other two options when trained on one data set and used on another. The hypothesised reason for this is that locus to locus variation in amplification efficiency varies with time, multimix batch, or from sample to sample.     

Unexpected findings and misdiagnoses in coroner’s autopsies performed for trauma at the University of the West Indies,Kingston, Jamaica

There has been significant improvement in medical diagnostic technology, but discrepancy rates between clinical and postmortem diagnoses remain relatively high. This study aimed to identify misdiagnoses and missed (unexpected) findings documented during complete coroner’s autopsies performed for trauma at the University of the West Indies (UWI) and evaluate their influence on patient outcome. We retrospectively reviewed the reports of all coroner’s autopsies performed for trauma, between 2003 and 2012, at the UWI. For each case, we extracted age, gender, trauma type, mechanism and topography, clinical and postmortem diagnoses and hospitalization duration. The data were used to calculate frequencies, proportions and discrepancy rates. 955 coroner’s autopsies were performed during the 10-year period; reports were available for 933. 396 of these were performed for trauma; 365 met the inclusion criteria. 260 (71.2%) of the 365 autopsies had at least one discrepancy. There were 746 clinical and 1118 autopsy diagnoses; 382 were discrepant (372 missed [unexpected] diagnoses, 6 mis-diagnoses and 4 over-diagnoses). The discrepancy rate (misdiagnoses and missed diagnoses) was 33.8%, and the majority (55%) occurred in patients hospitalized for <1 day. Cardiopulmonary diseases were the most commonly missed diagnoses. The discrepancy rate was intermediate to those previously reported in the literature. The short hospitalization duration in most patients suggests that limited time for clinical investigation may be a contributor to discrepancy. However, increased awareness among clinicians of the common major missed diagnoses should enhance their early diagnosis, even when clinical signs are subtle, hopefully producing improved patient outcome.