Repetitive Transcranial Magnetic Stimulation of Dorsolateral Prefrontal Cortex Affects Performance of the Wisconsin Card Sorting Task during Provision of Feedback

Early functional neuroimaging studies of tasks evaluating executive processes, such as the Wisconsin card sorting task (WCST), only assessed trials in blocks that may contain a large amount of different cognitive processes. More recently, we showed using event-related fMRI that the dorsolateral prefrontal cortex (DL-PFC) significantly increased activity during feedback but not matching periods of the WCST, consistent with its proposed role in the monitoring of information in working memory. Repetitive transcranial magnetic stimulation (rTMS) is a method that allows to disrupt processing within a given cortical region and to affect task performance for which this region is significantly solicited. Here we applied rTMS to test the hypothesis that the DL-PFC stimulation influences monitoring of working memory without interfering with other executive functions. We applied rTMS to the right DL-PFC and the vertex (control site) in different time points of the WCST. When rTMS was applied to the DL-PFC specifically during the period when subjects were receiving feedback regarding their previous response, WCST performance deteriorated, while rTMS did not affect performance during matching either when maintaining set or during set-shifting. This selective impairment of the DL-PFC is consistent with its proposed role in monitoring of events in working memory

Calsyntenins Function as Synaptogenic Adhesion Molecules in Concert with Neurexins

SummaryMultiple synaptic adhesion molecules govern synapse formation. Here, we propose calsyntenin-3/alcadein-β as a synapse organizer that specifically induces presynaptic differentiation in heterologous synapse-formation assays. Calsyntenin-3 (CST-3) is highly expressed during various postnatal periods of mouse brain development. The simultaneous knockdown of all three CSTs, but not CST-3 alone, decreases inhibitory, but not excitatory, synapse densities in cultured hippocampal neurons. Moreover, the knockdown of CSTs specifically reduces inhibitory synaptic transmission in vitro and in vivo. Remarkably, the loss of CSTs induces a concomitant decrease in neuron soma size in a non-cell-autonomous manner. Furthermore, α-neurexins (α-Nrxs) are components of a CST-3 complex involved in CST-3-mediated presynaptic differentiation. However, CST-3 does not directly bind to Nrxs. Viewed together, these data suggest that the three CSTs redundantly regulate inhibitory synapse formation, inhibitory synapse function, and neuron development in concert with Nrxs

Myeloid cells protect corneal nerves against sterile injury through negative-feedback regulation of TLR2–IL-6 axis

Background Mounting evidence suggests that the immune system plays detrimental or protective roles in nerve injury and repair. Main body Herein we report that both CD11bhiLy6Ghi and CD11bhiLy6ChiLy6Glo myeloid cells are required to protect corneal nerves against sterile corneal injury. Selective depletion of CD11bhiLy6Ghi or CD11bhiLy6ChiLy6Glo cells resulted in aggravation of corneal nerve loss, which correlated with IL-6 upregulation. IL-6 neutralization preserved corneal nerves while reducing myeloid cell recruitment. IL-6 replenishment exacerbated corneal nerve damage while recruiting more myeloid cells. In mice lacking Toll-like receptor 2 (TLR2), the levels of IL-6 and myeloid cells were decreased and corneal nerve loss attenuated, as compared to wild-type and TLR4 knockout mice. Corneal stromal fibroblasts expressed TLR2 and produced IL-6 in response to TLR2 stimulation. Conclusion Collectively, our data suggest that CD11bhiLy6Ghi and CD11bhiLy6ChiLy6Glo myeloid cells confer corneal nerve protection under sterile injury by creating a negative-feedback loop to suppress the upstream TLR2–IL-6 axis that drives corneal nerve loss

Diurnal variation in quantitative pupillary reactivity in large hemispheric stroke

Background Pupillary light reflex (PLR) assessment is an important neurological examination reflecting neurological deterioration in severe stroke cases. This study investigated the impact of diurnal variation in the PLR using quantitative pupillometry in stable patients with large hemispheric stroke. Methods We included 35 patients with large hemispheric stroke without neurological worsening, who were admitted to the neurological intensive care unit between April 2017 and November 2021. Quantitative pupillometry was performed every 4 hours. Pupillometer parameters of maximum pupil size, percentage of constriction (%CH), latency (LAT), constriction velocity (CV), dilation velocity (DV), maximum constriction velocity (MCV), and neurological pupil index (NPi) score were recorded. We evaluated changes in the pupillometer parameters over time using linear mixed model analysis. Results The diurnal variations revealed that the following parameters were significantly higher at 04:00 than at 20:00: maximum pupil size (right [Rt]: 3.59 vs. 3.21 mm, P<0.001; left [Lt]: 3.51 vs. 3.18 mm, P<0.001), %CH (Rt: 31.48 vs. 25.72, P<0.001; Lt: 31.42 vs. 24.98, P<0.001), CV (Rt: 1.97 vs. 1.68 mm/sec, P<0.001; Lt: 1.98 vs. 1.65 mm/sec, P<0.001), and DV (Rt: 0.97 vs. 0.84 mm/sec, P<0.001; Lt: 0.94 vs. 0.82 mm/sec, P=0.001). However, no significant diurnal variations were observed in the NPi values. Conclusion Pupillary dynamics based on quantitative pupillometer parameters, including the NPi, demonstrated diurnal variations over 24 hours in large hemispheric stroke patients without neurological worsening. However, all changes in the pupillometer parameters were within normal ranges

A fatal case of acute pulmonary embolism caused by right ventricular masses of acute lymphoblastic lymphoma-leukemia in a 13 year old girl

We report a case of a 13-year-old girl with acute lymphoblastic lymphoma-leukemia, who presented with a cardiac metastasis in the right ventricle, resulting in a pulmonary embolism. At the time of her leukemia diagnosis, a cardiac mass was incidentally found. The differential diagnosis for this unusual cardiac mass included cardiac tumor, metastasis, vegetation, and thrombus. Empirical treatment was initiated, including anticoagulation and antibiotics. She underwent plasmapheresis and was administered oral prednisolone for her leukemia. Five days later, she experienced sudden hemodynamic collapse and required extracorporeal membrane oxygenation insertion and emergency surgery. These interventions proved futile, and the patient died. Pathology revealed that the cardiac mass comprised an aggregation of small, round, necrotic cells consistent with leukemia. This is the first known case of acute lymphoblastic leukemia presenting as a right ventricular mass, with consequent fatal acute pulmonary embolism. A cardiac mass in a child with acute leukemia merits investigation to rule out every possible etiology, including vegetation, thrombus, and even a mass of leukemic cells, which could result in the fatal complication of pulmonary embolism

Atrophic Gastritis: A Related Factor for Osteoporosis in Elderly Women

Purpose Osteoporosis poses a great threat to the aging society. Hypochlorhydric or achlorhydric conditions are risk factors for osteoporosis. Atrophic gastritis also decreases gastric acid production; however, the role of atrophic gastritis as a related factor for osteoporosis is unclear. We investigated the relationship between atrophic gastritis and osteoporosis in postmenopausal women over 60 years of age. Subjects and Methods A total of 401 postmenopausal women were included in this cross-sectional study, which was conducted during their medical check-ups. Bone mineral densitometry was measured using a dual energy X-ray absorptiometry. Atrophic gastritis was defined endoscopically if gastric mucosa in the antrum and the body were found to be atrophied and thinned and submucosal vessels could be well visualized. Results: The proportion of people with atrophic gastritis was higher in the osteoporotic group than in the group without osteoporosis. A linear relationship was observed in the proportion of atrophic gastritis according to the categories of normal, osteopenia, and osteoporosis at the lumbar spine (p for trend = 0.039) and femur (p for trend = 0.001). A multiple logistic regression analysis revealed that the presence of atrophic gastritis was associated with an increased odds of osteoporosis after adjusting for age, body mass index, triglyceride, high-density lipoprotein cholesterol, alcohol consumption, and smoking status (odds ratio 1.89, 95% confidence interval 1.15–3.11). Conclusions: Atrophic gastritis is associated with an increased likelihood of osteoporosis in Korean elderly women