Which short tandem repeat polymorphisms are required for identification? Lessons from complicated kinship cases

This paper presents 5 examples of complicated deficient parentage cases, which were sufficiently resolved by extensive DNA typing using short tandem repeat (STR) and restriction fragment length polymorphisms (RFLPs). The latter have greatly contributed to the solution of deficiency cases, although their application is only feasible, if high molecular weight DNA and time are in abundance. This apart, RFLP technique is available in a few laboratories only, and its extinction can be expected in medium term. This development will pose a problem unless more highly polymorphic STR systems are at the service of forensic genetic laboratories. The required "new" additional STR polymorphisms must be able to fully replace RFLPs in terms of their respective information content. STR loci of this quality are e.g. ACTBP2 (SE33), D5S2360, and gonosomal loci. Moreover, the newly introduced STR kit "Humantype Chimera" is considered valuable from this point of view.     

Attractive properties of sexual pheromones in mice: innate or learned?

It is generally assumed that chemical signals (sexual pheromones) constitute the primary stimulus for sexual attraction in many mammals. However, it is unclear whether these pheromones are volatile or nonvolatile and which sensory systems are involved in their detection (vomeronasal and/or olfactory). Moreover, it has been demonstrated that experience influences the behavioral response to sexual pheromones and the sensory systems implicated. In order to clarify this issue, the attractive properties of volatile and nonvolatile components of the male-soiled bedding have been analyzed in female mice that had no previous experience with adult male-derived chemical signals (chemically na?ve females) using two-choice preference tests. The results indicate that some nonvolatile male-derived substances exert an innate attraction to females, but volatiles derived from male-soiled bedding do not attract chemically nai;ve females. Therefore, the primary attractive sexual pheromone includes a nonvolatile compound (e.g. major urinary proteins, MUPs). On the other hand, male-derived volatiles become attractive to females because of repeated exposure to male-soiled bedding. This represents a Pavlovian-like associative learning in which previously neutral volatiles (very likely odorants) acquire attractive properties by association with the nonvolatile, innately attractive pheromone(s). These findings indicate that not only the sexual but also the 'chemical' experience (previous experience with sexual pheromones) has to be taken into account to interpret the role of chemicals as releaser or primer pheromones. The sensory systems involved in the detection of these stimuli and the neural basis of the odor-pheromone association are discussed.     

Nonexpressing homozygotes for C282Y hemochromatosis: minority or majority of cases?

Genetic testing for the C282Y mutation of the HFE gene has been a major advance in the diagnosis of hereditary hemochromatosis. In most studies, more than 90% of typical hemochromatosis patients are homozygous for the C282Y mutation. Large-scale population screening studies in predominantly Caucasian populations have demonstrated a high prevalence of C282Y homozygotes of approximately 1 in 300. Despite this high prevalence by genetic testing, the clinical diagnosis of hemochromatosis and mortality from the disease are much less common. One possibility is the presence of many undiagnosed cases with nonspecific symptoms, and deaths occurring that are attributed to liver disease, diabetes, and heart disease without the recognition of iron overload secondary to hemochromatosis. Another possibility is a high prevalence of nonexpressing homozygotes. In this review, the available data on nonexpressing C282Y homozygotes is collected including information on pathogenesis, environmental interactions, and implications for population screening using genetic testing.     

Inferring antibiotic susceptibility from metagenomic data: dream or reality?

BackgroundThe diagnosis of bacterial infections continues to rely on culture, a slow process in which antibiotic susceptibility profiles of potential pathogens are made available to clinicians 48 hours after sampling, at best. Recently, clinical metagenomics, the metagenomic sequencing of samples with the purpose of identifying microorganisms and determining their susceptibility to antimicrobials, has emerged as a potential diagnostic tool that could prove faster than culture. Clinical metagenomics indeed has the potential to detect antibiotic resistance genes (ARGs) and mutations associated with resistance. Nevertheless, many challenges have yet to be overcome in order to make rapid phenotypic inference of antibiotic susceptibility from metagenomic data a reality.ObjectivesThe objective of this narrative review is to discuss the challenges underlying the phenotypic inference of antibiotic susceptibility from metagenomic data.SourcesWe conducted a narrative review using published articles available in the National Center for Biotechnology Information PubMed database.ContentWe review the current ARG databases with a specific emphasis on those which now provide associations with phenotypic data. Next, we discuss the bioinformatic tools designed to identify ARGs in metagenomes. We then report on the performance of phenotypic inference from genomic data and the issue predicting the expression of ARGs. Finally, we address the challenge of linking an ARG to this host.ImplicationsSignificant improvements have recently been made in associating ARG and phenotype, and the inference of susceptibility from genomic data has been demonstrated in pathogenic bacteria such as Staphylococci and Enterobacterales. Resistance involving gene expression is more challenging however, and inferring susceptibility from species such as Pseudomonas aeruginosa remains difficult. Future research directions include the consideration of gene expression via RNA sequencing and machine learning.     

Mixed anxiety-depression in a 1 year follow-up study: shift to other diagnoses or remission?

BACKGROUND: In 1992, the ICD-10 introduced the concept of mixed anxiety-depression disorder (MAD). However, a study examining the stability of this ICD-10-diagnosis is lacking. Our objective was to examine the 12 month outcome of MAD in comparison to the outcome of depression, anxiety, and comorbid depression and anxiety. METHODS: 85 MAD patients, 496 patients with major depression, 296 patients with anxiety disorders, and 306 comorbid patients were reassessed after 12 months. Rates of depression, anxiety, and MAD were compared using chi(2)-tests. RESULTS: While depressive disorders and anxiety disorders showed relatively high stability, MAD Patients had no higher rates of MAD at follow-up than patients with depression, anxiety or both. LIMITATIONS: Detailed information regarding treatment and disorders during the follow-up interval was lacking. Prevalence rates of MAD in single centres were too small for contrasting centres. CONCLUSIONS: MAD cannot be seen as a stable diagnosis: Most of MAD patients remit; many of them shift to other diagnoses than depression or anxiety. The ICD-10 criteria have to be specified more exactly.     

Mixed tumor or myoepithelioma of the skin? Histologic and immunohistochemical features

Mixed tumor, first reported in the parotid gland, is formed from the proliferation of epithelial and myoepithelial cells in a mesenchymatous stroma. We report the case of a woman hospitalized for a subcutaneous nodule of the thigh, characterized by a fast increased in size in 8 months. Microscopic analysis showed a proliferation of grouped and isolated spindle cells, without atypia or mitotic features. Few tubular features were noted. Stroma was hyalinized or myxoid. Neoplastic cells displayed immunohistochemical positivity with smooth muscle actin, keratin and S-100 protein. This neoplasm appeared mesenchymatous. The diagnosis was mixed tumor with a predominant myoepithelial component. This case underlines the difficulties encountered in defining this neoplasm. Some authors consider that myoepithelioma is a monophasic variant of mixed tumor; others consider that myoepithelioma is different from mixed tumor because its is more aggressive prognosis. The evolution of our case suggests that a myoepithelial differentiation should be a ma of poor prognosis.     

The first two cases of 2019-nCoV in Italy: Where they come from?

A novel Coronavirus, 2019-nCoV, has been identified as the causal pathogen of an ongoing epidemic, with the first cases reported in Wuhan, China, last December 2019, and has since spread to other countries worldwide, included Europe and very recently Italy. In this short report, phylogenetic reconstruction was used to better understand the transmission dynamics of the virus from its first introduction in China focusing on the more recent evidence of infection in a couple of Chinese tourists arrived in Italy on 23rd January 2020 and labeled as Coronavirus Italian cases. A maximum clade credibility tree has been built using a dataset of 54 genome sequences of 2019-nCoV plus two closely related bat strains (SARS-like CoV) available in GenBank. Bayesian time-scaled phylogenetic analysis was implemented in BEAST 1.10.4. The Bayesian phylogenetic reconstruction showed that 2019-2020 nCoV firstly introduced in Wuhan on 25 November 2019, started epidemic transmission reaching many countries worldwide, including Europe and Italy where the two strains isolated dated back 19 January 2020, the same that the Chinese tourists arrived in Italy. Strains isolated outside China were intermixed with strains isolated in China as evidence of likely imported cases in Rome, Italy, and Europe, as well. In conclusion, this report suggests that further spread of 2019-nCoV epidemic was supported by human mobility and that quarantine of suspected or diagnosed cases is useful to prevent further transmission. Viral genome phylogenetic analysis represents a useful tool for the evaluation of transmission dynamics and preventive action.     

Leukocyte circulation: one-way or round-trip? Lessons from primary immunodeficiency patients

The identification of chemokines has profoundly changed the way we interpret the immune response, elucidating the mechanism by which inflammatory cells are recruited to the site of infection by local secretion of chemoattractants such as CXC chemokine ligand 8 (CXCL8)/interleukin-8, chemokine ligand 2 (CCL2)/monocyte chemoattractant protein 1. This novel view of the immune response has been remodeled further following observations that lymphoid tissue development derives from the coordinated secretion of homeostatic chemokines such as CCL19, CCL21, and CXCL13, which mediate recruitment and clustering of the cells involved in lymphoid organogenesis. The study of primary immunodeficiencies has demonstrated that the number of circulating leukocytes is dependent on migration amongst bone marrow, blood circulation, and inflamed tissues. Defects of leukocyte adhesion and chemotaxis as a result of mutations of beta2-integrins lead to abnormal leukocytosis and susceptibility to skin infections, as observed in leukocyte adhesion deficiency. Conversely, neutropenia in children with myelokathexis is a result of leukocyte retention in the bone marrow because of the mutations of CXC chemokine receptor 4, which affect the capacity of cells to recirculate between blood and bone marrow. Moreover, the identification of the genetic basis of primary immunodeficiencies has shown that many primary immunodeficiencies such as Wiskott-Aldrich syndrome and common variable immunodeficiencies are characterized by altered migration of leukocytes and/or disregulation of cellular response to chemokines. This paper will be focused on the interpretation of primary immunodeficiencies as defects in leukocyte circulation between blood and primary and secondary organs.     

Additional slides from residual ThinPrep Pap tests: Of potential diagnostic benefit in equivocal cases?

The aim of this study was to further evaluate the diagnostic significance of additional slides prepared from residual ThinPrep (TP) Pap Tests. Up to 10 repeat slides were prepared from 105 residual TP cervical samples. All additional slides were evaluated for the presence of diagnostic elements which were not found on the primary TP slide. After the evaluation of the repeat slides, an upgraded diagnosis was noted in 15 cases (14.3%). The reclassified cases included: three negative cases reclassified as two ASC-US and as one LSIL, seven cases of ASC-US reclassified as six LSIL and as one HSIL, and five cases of LSIL reclassified as HSIL. The highest rate (7/15 cases, 46.7%) of cases with an upgraded diagnosis was noted in the ASC-US diagnostic category. Our results suggest that repeat processing of residual TP cervical samples may represent an adjunctive diagnostic tool for a more accurate classification of ASC-US cases. Nevertheless, the practical value of this approach seems to be limited by its significant cost and its uncertain effectiveness.     

Deviations from protocol in a complex trauma environment: errors or innovations?

Protocol standardizations are important for consistent and safe practices. However, complex clinical environments are highly dynamic in nature and often require clinicians, confronted with non-standard situations, to adjust and deviate from standard protocol. Some of these deviations are errors which can result in harmful outcomes. On the other hand, some of the deviations can be innovations, which are dynamic adjustments to the protocols made by people to adapt the current operational conditions and achieve high accuracy and efficiency. However, there is very little known about the underlying cognitive processes that are related to errors and innovations. In this study we investigate the extent to which deviations are classified as errors or innovations, as a function of expertise in a trauma setting. Field observations were conducted in a Level 1 trauma unit. A total of 10 trauma cases were observed and collected data was analyzed using measures that included customized activity-error-innovation ontology, timestamps and expertise of the team members. The results show that expertise of the caregivers and criticality of a patient's condition in critical care environment influence the number and type of deviations from standard protocol. Experts' deviations were a combination of errors and innovations; whereas the novices' deviations were mostly errors. This research suggests that a novel approach must be taken into consideration for the design of protocols (including standards) and compliance measurements in complex clinical environments.