A threat to a virtual hand elicits motor cortex activation

We report an experiment where participants observed an attack on their virtual body as experienced in an immersive virtual reality (IVR) system. Participants sat by a table with their right hand resting upon it. In IVR, they saw a virtual table that was registered with the real one, and they had a virtual body that substituted their real body seen from a first person perspective. The virtual right hand was collocated with their real right hand. Event-related brain potentials were recorded in two conditions, one where the participant’s virtual hand was attacked with a knife and a control condition where the knife only struck the virtual table. Significantly greater P450 potentials were obtained in the attack condition confirming our expectations that participants had a strong illusion of the virtual hand being their own, which was also strongly supported by questionnaire responses. Higher levels of subjective virtual hand ownership correlated with larger P450 amplitudes. Mu-rhythm event-related desynchronization in the motor cortex and readiness potential (C3–C4) negativity were clearly observed when the virtual hand was threatened—as would be expected, if the real hand was threatened and the participant tried to avoid harm. Our results support the idea that event-related potentials may provide a promising non-subjective measure of virtual embodiment. They also support previous experiments on pain observation and are placed into context of similar experiments and studies of body perception and body ownership within cognitive neuroscience.     

Thalamic diffusion differences related to cognitive function in white matter lesions

Cerebral white matter lesions (WMLs) are related to cognitive deficits, probably due to a disruption of frontal–subcortical circuits. We explored thalamic diffusion differences related to white matter lesions (WMLs) and their association with cognitive function in middle-aged individuals. Ninety-six participants from the Barcelona-AsIA Neuropsychology Study were included. Participants were classified into groups based on low grade and high grade of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs). Tract-Based Spatial Statistics was used to study thalamic diffusion differences between groups. Mean fractional anisotropy (FA) values in significant areas were calculated for each subject and correlated with cognitive performance. Participants with high-grade PVHs and DWMHs showed lower FA thalamic values compared to those with low-grade PVHs and DWMHs, respectively. Decreased FA thalamic values in high-grade DWMHs, but not high-grade PVH, were related to lower levels of performance in psychomotor speed, verbal fluency, and visuospatial skills. Thalamic diffusion differences are related to lower cognitive function only in participants with high-grade DWMHs. These results support the hypothesis that fronto–subcortical disruption is associated with cognitive function only in DWMHs.     

Selected angiogenic cytokines in systemic lupus erythematosus patients

The objective of this study was to determine the serum concentration of angiogenic factors (vascular endothelial growth factor, VEGF; transforming growth factor beta, TGF-β1; hepatic growth factor, HGF; basic fibroblast growth factor, bFGF; tumor necrosis factor alpha, TNF-α; soluble vascular endothelial growth factor receptor 1, sVEGF-R1; soluble vascular endothelial growth factor receptor 2, sVEGF-R2), the relationships among them and to assess the relation of their levels with the applied therapy in 48 females with systemic lupus erythematosus (SLE; 37 long-term treated +11 newly diagnosed). The control group consisted of 24 healthy women. A statistically significant increase of sVEGF-R2 and significant decrease of sVEGF-R1 were observed in the subgroup of newly diagnosed SLE patients as compared to the control subjects. No significant differences were found between serum angiogenic factors in the long-term treated subgroup and the control, the long-term treated subgroup and the newly diagnosed SLE patients after a 3-month treatment, and the subgroup of newly diagnosed SLE patients before therapy and after a 3-month treatment. The significant decrease in the serum of sVEGF-R2 was revealed in the subgroup treated for a long-time as compared to the subgroup of newly diagnosed untreated SLE patients. The analysis of relationships between serum concentration of sVEGF-R1 and other cytokines levels revealed positive correlation with concentration of VEGF and TNF-α in the total group of patients. In the newly diagnosed untreated subgroup, a strong positive correlation between concentration of sVEGF-R1 and bFGF was observed. Furthermore, a moderate positive correlation between concentration of sVEGF-R1 and the level of VEGF was revealed in the long-term treated patients. The association between sVEGF-R2 and HGF was also noted in this subgroup. The obtained data suggest the necessity of further investigations to determine the importance of angiogenic factors in pathogenesis and therapy of SLE.     

Chromosome microarray analysis should be offered to all invasive prenatal diagnostic testing following a normal rapid aneuploidy test result

Chromosomal microarray analysis (CMA) has now replaced karyotyping in the analysis of prenatal cases with a fetal structural anomaly, whereas in those pregnancies undergoing invasive prenatal diagnosis with a normal fetal ultrasound, conventional karyotyping is still performed. The aims of this study were to establish the diagnostic yield of CMA in prenatal diagnosis, and to provide new data that might contribute to reconsider current practices. We reviewed 2905 prenatal samples with a normal rapid aneuploidy detection test referred for evaluation by CMA testing. Our study revealed pathogenic and reported susceptibility copy number variants associated with syndromic disorders in 4.8% (n = 138/2905) of cases, being 2.8% (n = 81/2905) the estimated added diagnostic value of CMA over karyotyping. Clinically significant CMA abnormality was detected in 5.4% (107/1975) of the fetuses with ultrasound anomalies and in 1.4% (5/345) of those considered as low-risk pregnancies. Our series shows that in prenatal samples, CMA increases 2-fold the diagnostic yield achieved by conventional karyotyping.     

Photo‐Crosslinked Side‐Chain Liquid‐Crystalline Elastomers for Microsystems

Photo‐crosslinkable side‐chain liquid‐crystalline polymers (LCPs) containing photoreactive benzophenone cores are synthesized in order to obtain their corresponding side‐chain liquid‐crystalline elastomers (LCEs). This strategic synthesis allows thin elastomeric films and their integration into microsystems for actuators and micromachines to be obtained. As an example of this principle, a gripper was developed. The position of its arms can be changed by applying voltages from 1.5 to 3.5 V at different rates. Small changes in the liquid‐crystalline elastomer film cause strains of up to 150% in the microdevice and the capacity to move up to 400 times its own mass due to the nematic‐to‐isotropic transformation.

     

FGF-4 increases in vitro expansion rate of human adult bone marrow-derived mesenchymal stem cells

Human bone marrow-derived mesenchymal stem cells (MSCs) exhibit limited in vitro growth. Fibroblast growth factors (FGFs) elicit a variety of biological responses, such as cell proliferation, differentiation and migration. FGF-4 represents one of the FGFs with the highest cell mitogenic activity. We studied the effect of FGF-4 on MSCs growth and pluripotency. MSCs duplication time (Td) was significantly reduced with FGF-4 compared to controls (2.2 +/- 0.2 vs. 4.1 +/- 0.2 days, respectively; p = 0.03) while BMP-2 and SCF-1 did not exert a significant growth effect. MSC expression of surface markers, differentiation into adipogenic and osteogenic lineages, and baseline expression of cardiomyogenic genes were unaffected by FGF-4. In summary, exogenous FGF-4 increases the rate at which MSC proliferate and has no significant effect on MSC pluripotency.     

Structures and serology of the O-antigens of Proteus strains classified into serogroup O17 and former serogroup O35

Introduction Bacteria of the genus Proteus are facultative pathogens which commonly cause urinary tract infections. Based on the serological specificity of the O-chain polysaccharide of the lipopolysaccharide (O-polysaccharide, O-antigen), strains of P. mirabilis and P. vulgaris have been classified into 60 serogroups. Studies on the chemical structure and serological specificity of the O-antigens aim at the elucidation of the molecular basis and improvement of the serological classification of these bacteria. Materials and Methods The O-polysaccharide was prepared by acetic acid degradation of the lipopolysaccharide isolated from dried bacterial mass of each strain by hot phenol/water extraction. ¹H- and ¹³C-NMR spectroscopy was used for structural studies. Serological studies were performed with rabbit O-antisera using enzyme immunosorbent assay, passive hemolysis test, and the inhibition of reactions in these assays as well DOC-PAGE and Western blot. Results Four Proteus strains belonging to serogroups O17 and O35 were found to possess similar O-polysaccharide structures, in particular having the same carbohydrate backbone built up of tetrasaccharide repeating units. However, they differ in the presence or absence of additional substituents, such as phosphoethanolamine in P. mirabilis O17 and glucose in P. penneri O17, as well as in the pattern and degree of O-acetylation of various monosaccharide residues. Serological studies also showed close relationships between the O-antigens studied. Conclusions Based on these data it is proposed to reclassify strain P. mirabilis PrK 61/57, formerly representing the O35 serogroup, into the serogroup O17 in the Kauffman-Perch classification system of Proteus.     

The Impact of Psychosis on Sexual Functioning: A Systematic Review

BackgroundSexual dysfunction among psychotic patients is highly prevalent. However, most research has focused on antipsychotic side effects on sexual functioning.AimTo provide evidence by means of a systematic review of the literature about the impact of psychosis on sexual functioning among unmedicated patients.MethodsSystematic search of MEDLINE (PubMed), Scopus, and Google Scholar for studies that reported sexual functioning among psychotic patients, who were drug-naïve or drug-free for at least 3 weeks before the study. Studies were published in English language between January 1994 and October 2019. We used the approach recommended by PRISMA, and the selection process was carried out by 2 reviewers.OutcomesThe outcome measures were sexual function and sexual dysfunctions.ResultsA total of 734 articles were obtained, 658 were obtained after duplicates were removed, 612 were excluded after reading the title and abstract, and 46 were included for a complete review of the articles. 5 papers were finally included. A total of 770 cases were included in the systematic review. The prevalence of sexual dysfunction in psychosis varied from 16.8% to 70% and in ultra-high state was 50%. It is noteworthy that those ultra–high-risk (prodromal) patients who develop psychosis had higher rates of sexual impairment. Therefore, we found higher rates of sexual dysfunction among untreated patients, both psychotic and ultra-high risk patients, than healthy controls.Clinical ImplicationsThe assessment of sexual behavior should be a part of routine psychiatric examination not only in psychotic but also in ultra–high-risk patients.Strengths & LimitationsThis is the first systematic review about the impact of psychosis on sexual functioning among unmedicated patients. However, scarce and heterogeneous studies were identified.ConclusionsImpaired sexual functioning is common in the onset of psychosis (or during ultra–high-risk state) and prior to the beginning of treatment. This suggests that psychotic symptoms and sexual dysfunction may have common etiological pathways at the psychosocial and neurobiological levels.Vargas-Cáceres S, Cera N, Nobre P, et al. The Impact of Psychosis on Sexual Functioning: A Systematic Review. J Sex Med 2021;18:457–466.     

Game theoretical mapping of white matter contributions to visuospatial attention in stroke patients with hemineglect

White matter bundles linking gray matter nodes are key anatomical players to fully characterize associations between brain systems and cognitive functions. Here we used a multivariate lesion inference approach grounded in coalitional game theory (multiperturbation Shapley value analysis, MSA) to infer causal contributions of white matter bundles to visuospatial orienting of attention. Our work is based on the characterization of the lesion patterns of 25 right hemisphere stroke patients and the causal analysis of their impact on three neuropsychological tasks: line bisection, letter cancellation, and bells cancellation. We report that, out of the 11 white matter bundles included in our MSA coalitions, the optic radiations, the inferior fronto‐occipital fasciculus and the anterior cingulum were the only tracts to display task‐invariant contributions (positive, positive, and negative, respectively) to the tasks. We also report task‐dependent influences for the branches of the superior longitudinal fasciculus and the posterior cingulum. By extending prior findings to white matter tracts linking key gray matter nodes, we further characterize from a network perspective the anatomical basis of visual and attentional orienting processes. The knowledge about interactions patterns mediated by white matter tracts linking cortical nodes of attention orienting networks, consolidated by further studies, may help develop and customize brain stimulation approaches for the rehabilitation of visuospatial neglect.