The effects of masseter muscle paralysis on facial bone growth

BACKGROUND: Understanding the effects of muscle function on facial bone growth may help us treat children with facial anomalies. Facial bone growth is known to be a result of both genetic and epigenetic influences. One of the main epigenetic factors controlling growth is thought to be muscle action. The purpose of this study was to establish a model of single facial muscle paralysis and to identify the effects masseter muscle paralysis has on mandible and zygoma growth. METHODS: Twenty New Zealand white rabbits were divided into control, paralysis, and sham groups. Masseter muscle paralysis was achieved with botulinum toxin A (BTX). Computed tomographic and single-photon emission computed tomography (SPECT) scans and cephalometric measurements were performed. Masseter weights and mandible and zygoma volumes, shapes, and metabolism were measured. RESULTS: Eighteen animals completed the study. Significant decreases in zygoma and mandible volumes with minimal changes in shape were seen on the paralyzed sides. SPECT showed a decrease in bone production in both zygomas and mandibles on the paralyzed sides. CONCLUSIONS: An animal model has been created in which the effects of single muscle paralysis on bone growth can be studied. Masseter muscle function may be responsible in maintaining mandible and zygoma volume by controlling bone production. Masseter function alone has less influence on mandible and zygoma shape.     

Regional differences in epidermal thickness and behavioral response following partial denervation of the rat paw

In order to investigate the relation between changes in epidermal thickness and pain-related behavior in different rat hind paw areas we performed partial denervation using two experimental models of neuropathic pain injury: spinal nerve ligation (SNL) and chronic constriction injury (CCI). Denervation produced significant epidermal thinning in both models. The most pronounced thinning was observed in the lateral paw region of the SNL group. Both models showed increase in hyperalgesic response during the postoperative period and no behavioral differences between testing regions. Our study showed that partial denervation induces regional differences in epidermal thinning but not in pain-related behavior.     

Transthoracic Echocardiography-Based Prediction Model of Adverse Event Risk in Patients with COVID-19

Cardiopulmonary disorders cause a significant increase in the risk of adverse events in patients with COVID-19. Therefore, the development of new diagnostic and treatment methods for comorbid disorders in COVID-19 patients is one of the main public health challenges. The aim of the study was to analyze patient survival and to develop a predictive model of survival in adults with COVID-19 infection based on transthoracic echocardiography (TTE) parameters. We conducted a prospective, single-center, temporary hospital-based study of 110 patients with moderate to severe COVID-19. All patients underwent TTE evaluation. The predictors of mortality we identified in univariate and multivariable models and the predictive performance of the model were assessed using receiver operating characteristic (ROC) analysis and area under the curve (AUC). The predictive model included three factors: right ventricle (RV)/left ventricle (LV) area (odds ratio (OR) = 1.048 per 1/100 increase, p = 0.03), systolic pulmonary artery pressure (sPAP) (OR = 1.209 per 1 mm Hg increase, p < 0.001), and right ventricle free wall longitudinal strain (RV FW LS) (OR = 0.873 per 1% increase, p = 0.036). The AUC-ROC of the obtained model was 0.925 ± 0.031 (95% confidence interval (95% CI): 0.863–0.986). The sensitivity (Se) and specificity (Sp) measures of the models at the cut-off point of 0.129 were 93.8% and 81.9%, respectively. A binary logistic regression method resulted in the development of a prognostic model of mortality in patients with moderate and severe COVID-19 based on TTE data. It may also have additional implications for early risk stratification and clinical decision making in patients with COVID-19.     

Genetic sub-structuring of Croatian island populations in the Southeastern European context: a meta-analysis

AimTo use the method of meta-analysis to assess the influence of island population isolation on the sub-structuring of the Croatian population, as well as the influence of regional population groups on the sub-structuring of the Southeastern European population with regard to basic population genetic statistical parameters calculated by using STR locus analysis.MethodsBio-statistical analyses were performed for 2877 unrelated participants of both sexes from Southeastern Europe. Nine autosomal STR loci (D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S82) were analyzed by using standard F-statistics and population structure analysis (Structure software).ResultsGenetic differentiation of Croatian subpopulations assessed with the F_ST method was higher at the level of the Croatian population (0.005) than at the level of Southeastern Europe (0.002). The island of Vis showed the most pronounced separation in the Croatian population, and Albanians from Kosovo in the population of Southeast Europe, followed by Croatia, Bosnia and Herzegovina, and Hungary.ConclusionThe higher structure of Croatian subpopulations in relation to Southeastern Europe suggest a certain degree of genetic isolation, most likely due to the influence of endogamy within rural island populations.

The island populations of the eastern Adriatic have been the subject of multidisciplinary anthropological research for almost 50 years, starting with the pioneering work of Rudan et al in 1972 (1). A number of specific features of these rural populations has been revealed, which make them exceptional models for studying ethno-cultural, historical, migratory, and demographic characteristics of this region. More specifically, evolutionary forces (bottleneck effect and genetic drift) increase genome homogeneity within the genetic structure of such island isolates by eliminating certain genetic traits in favor of others and increasing the likelihood of finding low-impact alleles (2,3). The reduced genetic and environmental diversity makes genetically isolated populations suitable for the study of different complex and rare Mendelian hereditary diseases, since the combined action of genetic drift, inbreeding, and founder effect increases the prevalence of such diseases when compared with the general population.Southeastern Europe was one of Europe’s glacial refugia during the ice age, and the origin of postglacial resettlement of Europe in the Paleolithic and Neolithic. Due to this specific role and its position at the crossroads of migrations to and from Europe, this area was extensively investigated in the field of population genetics (4-7). Different genetic markers have been used to investigate the genetic landscape of Europe and determine the patterns of population sub-structuring at the regional and continental level (8). As a part of the comprehensive anthropological research on the population structure of Croatian island isolates, microsatellite DNA from different subpopulations has been previously analyzed to determine genetic diversity, population structure, and the degree of isolation of island populations (9). Similar studies were also conducted on a representative sample of the general Croatian population and other isolated populations from Southeastern Europe (10-12).This study represents a continuation of previous anthropogenetic research (6,13-16). We used statistical and analytical methods of meta-analysis to synthesize data from previously conducted, mutually independent studies of island and continental populations of Croatia and Southeastern Europe (Figure 1) based on analyses of autosomal STR markers, and data analyzed in this study for the first time.Open in a separate windowFigure 1Division of the sample into two hierarchical groups (left) and geographical position of the investigated Croatian subpopulations (right). NDI – North Dalmatian islands.The aim of this study was to determine the genetic characteristics of populations from Southeastern Europe, with special reference to Croatian island populations, and to investigate the effect of specific intrapopulation genetic structure on interpopulation relationships. Namely, a specific aim was to investigate the influence of island population isolation on the sub-structuring of the Croatian population, and the influence of regional population groups on the sub-structuring of Southeastern Europe with regard to basic population genetic statistical parameters calculated by using STR locus analysis.     

Influence of genetic substructuring of statistical forensic parameters on genetic short tandem repeat markers in the populations of Southeastern Europe

AimTo investigate the influence of specific intrapopulation genetic structures on interpopulation relationships. Special focus was the influence of island population isolation on the substructuring of the Croatian population, and the influence of regional population groups on the substructuring of Southeast European populations.MethodsAutosomal short tandem repeat (STR) loci were analyzed by using four forensic parameters: matching probability (PM), power of discrimination (PD), power of exclusion (PE), and polymorphic information content (PIC) on a sample of 2877 unrelated participants of both sexes. A sample set comprising 590 participants was analyzed for the first time, and 2287 participants were included from previous studies. The analysis was performed with PowerStats v. 1.2.ResultsThe analysis of forensic parameters for all nine loci in the Croatian subpopulations showed the largest deviations in the populations of the islands of Korčula and Hvar. The smallest deviations were found in the mainland population. As for Southeast European populations, the largest deviations were found in the population of North Macedonia, followed by Romania, Albanians from Kosovo, and Montenegro, while the smallest deviations were found in the population of Hungary.ConclusionThe comparison of forensic parameters between different subpopulations of Croatia and Southeast Europe indicates that the isolation of individual Croatian subpopulations and rare alleles in their gene pool affect the values of forensic parameters. Specific features of (sub)populations should be taken into account for appropriate sampling of the total population when creating a DNA database of STR markers.

Microsatellite markers are used in forensic research due to their high power of discrimination (PD) (usually >0.9, with observed heterozygosity >70%), position at separate chromosome locations (to avoid closely related loci), consistency and reproducibility of results after multiplication with other markers, and rare occurrences of stutter products (1). The use of short tandem repeat (STR) markers in paternity testing and forensic genetic analysis increases the PE from an initial 30% to 40% for blood typing, 80% for tissue typing, HLA analysis, 90% for combinations of HLA analysis with serological tests, and finally 99.99% for RFLP analysis to a minimum of 99.999% (2-4). In forensic research, the advantage of microsatellite markers is the possibility of simultaneous analysis of multiple loci in multiplex STR systems, which allows a high degree of individualization in identifying traces. In forensic applications where DNA is usually degraded, microsatellite markers of 100 to 400 bp are better markers than minisatellites (VNTRs) of 400 to 1000 bp (4).Microsatellite DNA differs for each person, but two people may have the same allelic variants at one or more STR loci. However, the probability of finding allelic variants in two individuals at, for example, 15 STR loci, analyzed using the PowerPlex 16 kit for the white population is 1.83 × 10¹⁷ (5). The average mutation rate for loci is variable, but its values are below 0.1%. Based on previous forensic research, the loci with the lowest mutation rate are CSF1PO, TH01, TPOX, D5S818, and D8S1179, while D21S11, FGA, D7S820, D16S539, and D18S51 have a significantly higher mutation rate (2,6-8).Specific population DNA databases serve to determine the genetic diversity of populations and to facilitate statistical calculations in forensic genetics. They are not based on individual DNA profiles, but the profiles represented in a particular population are used to determine allelic frequencies for further statistical calculations, ie, analysis of forensic identification parameters based on the assessment of PM, PD, PE, degree of loci heterozygosity (H), and likelihood ratio (LR). In order to form the most representative database of a certain population, it is important to investigate the genetic diversity of the population, its features, size, isolation, and the degree of genetic differentiation in relation to neighboring and distant populations (4).Therefore, the aim of this study was to investigate the existence of substructured subpopulations in Croatia, and the impact of their specific intrapopulation genetic structure on interpopulation relationships, and how these relationships affect the basic forensic statistical parameters of genetic STR markers.     

Data from a microdosed recombinant human erythropoietin administration study applying the new biotinylated clone AE7A5 antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis protocol

Erythropoietin (EPO) is a hormone, which stimulates the production of red blood cells. Due to its performance-enhancing effect, it is prohibited by the World Anti-Doping Agency (WADA). In order to reduce the detection window of EPO doping, athletes have been applying low doses of recombinant EPO (e.g., <10 IU/kg body weight, daily or every second day) instead of larger doses twice or more per week (e.g., 30 IU/kg). Microdoses of Retacrit (epoetin zeta), an EPO biosimilar, were administered intravenously and subcutaneously to human males and females. Urine and serum samples were collected and analysed applying the new biotinylated clone AE7A5 EPO antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis (SAR-PAGE) protocol. With the improved protocol, microdosed Retacrit (7.5 IU/kg body weight [BW]) was detectable for at least 52 h after intravenous administration. Detection windows were approximately the same for serum and urine and doubled after subcutaneous administration (~104 h). Previous studies applying different electrophoretic techniques and the not further optimized SAR-PAGE protocol revealed considerably shorter detection windows for recombinant human erythropoietin (rhEPO) microdoses. Because the new biotinylated antibody performed significantly more sensitive than the nonbiotinylated version, the new protocol will improve the sensitivity and hence detectability of recombinant EPO in doping control.