Age distribution and disease severity of COVID-19 patients continued to change in a time-dependent manner from May 2021 to April 2022 in the regional core hospital in Japan.

The present retrospective study aimed to examine the real-world data regarding time-dependent changes in the age distribution of patients with coronavirus disease 2019 (COVID-19) as well as the severity and infectivity in a regional core hospital in Japan. Patients with COVID-19 who visited the fever outpatient branch in Takagi Hospital during phase I (May 1 to December 31, 2021), and during phase II (January 1 to April 30, 2022) were evaluated. The age distribution of outpatients and the characteristics of inpatients aged > 75 years were compared between phases I and II. The age distribution of outpatients shifted from the older generation in phase I to the younger generation in phase II (p < 0.01). Disease severity might be reduced in a time-dependent manner with a decrease in the hospitalization rate (phase I: 145/368 (39.4%); phase II: 104/1496 (7.0%); p < 0.01) and mortality rate (phase I: 10/368 (2.7%); phase II: 7/1496 (0.5%); p < 0.01). The number of patients increased in phase II (374.0/month) compared to that in phase I (36.8/month). Regarding the older inpatients, the disease severity of COVID-19 and hospitalization days were reduced in phase II compared to those in phase I (p < 0.01, each). In conclusion, the present study suggests a change in the age distribution of patients with COVID-19, a decrease in toxicity, and an increase in infectivity of severe acute respiratory syndrome coronavirus 2 in a time-dependent manner.

De novo KCNT1 mutations in early-onset epileptic encephalopathy.

KCNT1 mutations have been found in epilepsy of infancy with migrating focal seizures (EIMFS; also known as migrating partial seizures in infancy), autosomal dominant nocturnal frontal lobe epilepsy, and other types of early onset epileptic encephalopathies (EOEEs). We performed KCNT1-targeted next-generation sequencing (207 samples) and/or whole-exome sequencing (229 samples) in a total of 362 patients with Ohtahara syndrome, West syndrome, EIMFS, or unclassified EOEEs. We identified nine heterozygous KCNT1 mutations in 11 patients: nine of 18 EIMFS cases (50%) in whom migrating foci were observed, one of 180 West syndrome cases (0.56%), and one of 66 unclassified EOEE cases (1.52%). KCNT1 mutations occurred de novo in 10 patients, and one was transmitted from the patient's mother who carried a somatic mosaic mutation. The mutations accumulated in transmembrane segment 5 (2/9, 22.2%) and regulators of K(+) conductance domains (7/9, 77.8%). Five of nine mutations were recurrent. Onset ages ranged from the neonatal period (<1 month) in five patients (5/11, 45.5%) to 1-4 months in six patients (6/11, 54.5%). A generalized attenuation of background activity on electroencephalography was seen in six patients (6/11, 54.5%). Our study demonstrates that the phenotypic spectrum of de novo KCNT1 mutations is largely restricted to EIMFS.

Different perceptual sensitivities for Chernoff's face between children and adults.

The aim of this study was to investigate the differences between children and adults in recognizing facial expressions of simple line drawings of "Chernoff's face". First, the angles of the eyebrows and mouth of Chernoff's face were changed in a stepwise way with a personal computer, and the emotional response of the subjects was evaluated by a questionnaire. Second, three drawings of non-target stimuli (neutral face, angry face, and wheelchair) and target stimuli were used to elicit event-related potentials (ERPs). Children had higher scores for the facial expressions than adults, and relied much more on the angles of the eyebrows and mouth. The major ERP findings were (1) the latencies of P100 and N170 were significantly longer in children than adults, (2) the amplitudes of P100 were significantly larger in children than adults, but the N170 amplitudes were not significantly different, and (3) a slow negative shift was recorded with a latency of 240-460ms at the posterior-temporal site for angry face compared with neutral face in adults but not in children. These results suggest that the differences in the electrophysiological recognition of facial expressions can be set at 240ms after appearance of the Chernoff's face in adults but not in children.

[A case of parietal lobe epilepsy with ictal laughter].

We report here about an 8-year-old boy with parietal lobe epilepsy (PLE) and ictal laughter. At the age of 6, he began to experience drop seizures, followed by sensory fits. Interictal EEG showed frequent spikes at C3, C4, P3 and Cz. Despite treatment with antiepileptic drugs, he often fell down in seizures after feeling abnormal sensations in the right shoulder. On ictal video EEG at the age of 7 years, (1) he became motionless and complained of fear and pain in the right hand, (2) he had clonic seizures of the right upper limb and fell down to his left, (3) he laughed though he did not feel funny. Ictal EEG showed spikes which originated in Pz and then were generalized. In many of the previously reported cases, ictal laughter is associated with hypothalamic hamartomas, infantile spasms,. complex partial seizures of frontal, temporal, or parietal origin. We diagnosed the present case as having PLE. However, other localization could not be roled out because the spikes were generalized quickly. To date, there are two reported cases of ictal laughter with PLE, but ictal EEG is lacking in these patients. Ictal laughter is rare in non-lesional cryptogenic PLE, but it may imply PLE's pathogenesis.

Non-invasive evaluation of face and motion perception in humans.

The neural mechanisms for the perception of face and motion were studied using psychophysical threshold measurements, event-related potentials (ERPs), and functional magnetic resonance imaging (fMRI). A face-specific ERP component, N170, was recorded over the posterior temporal cortex. Removal of the high-spatial-frequency components of the face altered the perception of familiar faces significantly, and familiarity can facilitate the cortico-cortical processing of facial perceptions. Similarly, the high-spatial-frequency components of the face seemed to be crucial for the recognition of facial expressions. Aging and visuospatial impairments affected motion perception significantly. Two distinct components of motion ERPs, N170 and P200, were recorded over the parietal region. The former was related to horizontal motion perception while the latter reflected the perception of radial optic flow motion. The results of fMRI showed that horizontal movements of objects and radial optic flow motion were perceived differently in the V5/MT and superior parietal lobe. We conclude that an integrated approach can provide useful information on spatial and temporal processing of face and motion non-invasively.