Wearing a face mask during controlled-intensity exercise is not a risk factor for exertional heatstroke: A pilot study.

AIM: This study aimed to measure the influence of wearing face masks on individuals' physical status in a hot and humid environment. METHODS: Each participant experienced different physical situations: (i) not wearing a mask (control), (ii) wearing a surgical mask, (iii) wearing a sport mask. An ingestible capsule thermometer was used to measure internal core body temperature during different exercises (standing, walking, and running, each for 20 min) in an artificial weather room with the internal wet-bulb globe temperature set at 28°C. The change in the participants' physical status and urinary liver fatty acid-binding protein (L-FABP) were measured. RESULTS: Six healthy male volunteers were enrolled in the study. In each participant, significant changes were observed in the heart rate and internal core temperatures after increased exercise intensity; however, no significant differences were observed between these parameters and urinary L-FABP among the three intervention groups. CONCLUSION: Mask wearing is not a risk factor for heatstroke during increased exercise intensity.

Midbrain volume increase in patients with panic disorder.

AIM: Although recent studies suggest abnormalities of the cerebral cortex, limbic structures, and brain stem regions in panic disorder (PD), the extent to which the midbrain is associated with PD pathophysiology is unclear. The aim of this study was to investigate structural abnormalities of the midbrain using magnetic resonance imaging and to determine if there is a clinical correlation between midbrain volume and clinical measurements in patients with PD. METHODS: Thirty-eight patients with PD (PD group) and 38 healthy controls (HC group) participated in this study. The midbrain was measured with a manual tracing method with high spatial resolution magnetic resonance imaging. The Panic Disorder Severity Scale and Global Assessment of Functioning were used to examine the correlation between volume abnormality and clinical symptoms and functioning in the PD group. RESULTS: Relative midbrain volume was larger in the PD group than in the HC group. The relative volume of the dorsal midbrain was larger in the PD group, while the volume of the ventral midbrain was not. We found a significant positive correlation between relative dorsal midbrain volume and total Panic Disorder Severity Scale score, and a significant negative correlation between relative dorsal midbrain volume and Global Assessment of Functioning score in the PD group. CONCLUSIONS: Our findings suggest that the dorsal midbrain is associated with PD pathophysiology. The midbrain volume increase may reflect PD severity.

Promomycin, a polyether promoting antibiotic production in Streptomyces spp.

Widespread interspecific stimulation of antibiotic production occurs in strains of Streptomyces owing to the activity of diffusible substances, as previously determined in our investigations of the cross-feeding effect. In this study, we newly isolated a substance produced by a Streptomyces strain closely related to Streptomyces scabrisporus, based on the observation that this substance induced the production of an unknown antibiotic in another strain related to Streptomyces griseorubiginosus. This substance, named promomycin, is a polyether structurally related to lonomycin. Promomycin itself had an antibiotic activity, but it stimulated antibiotic production in multiple Streptomyces strains at sub-inhibitory concentrations. Evidence implies that this stimulation effect is widespread within this group of bacteria.

Use of restraint in a general hospital psychiatric unit in Japan.

Few analyses have been carried out in Japan concerning factors contributing to physical restraint of patients. We compared demographic data for 241 inpatients who were restrained during a 4-year period with data for 1093 inpatients who were not restrained in a general hospital psychiatric unit in Japan. Increased likelihood of restraint use was associated with older age, male gender, off-hours admission, involuntary hospitalization, transfer from other departments of the hospital, frequent hospitalization, absence of previous treatment, physical complications, history of suicide attempts, organic mental disorders, mental and behavioral disorders from psychoactive substance use, schizophrenia, schizotypal and delusional disorders. Importantly, physical complications not only were more prevalent among restrained than unrestrained patients, but additionally in restrained patients physical complications were associated with more prolonged hospitalization and periods under restraint than were associated with assaultive behavior or periods of unconsciousness. In conclusion, general hospital psychiatric units in Japan often treat patients with psychiatric disorders or symptoms that were associated with physical problems. Particular caution is needed in deciding whether such patients should be restrained since hospitalization may be prolonged or functional status compromised.

[Progressive structural abnormalities in the brain of the schizophrenic].

One hundred years ago, Kraepelin hypothesized that cerebral damage might cause dementia praecox. Many patients with schizophrenia show progressive clinical deterioration, although the evidence has remained unclear for the organic brain damage. Recently, brain abnormalities have been suggested, including enlargement of the lateral ventricles and reduction of the frontal and temporal lobes, due to the development of magnetic resonance imaging (MRI). Changes in brain structures have also been reported in the clinical course of schizophrenia. These structural brain studies have played important roles in clarifying the pathophysiology of schizophrenia and understanding the association of clinical symptoms with morphological brain change. However, there have been inconsistencies in the results on progressive structural changes. The selection of the patients, effects of medication, and social environmental factors may account for these inconsistencies. We have reviewed recent studies that found structural changes in the brain, including subcortical and ventricular of the schizophrenia.

Psychomotor retardation correlates with frontal hypoperfusion and the Modified Stroop Test in patients under 60-years-old with major depression.

Frontal hypoperfusion and frontal dysfunction have been reported in patients with major depression. It was also found that frontal hypoperfusion correlated with frontal dysfunction evaluated by neuropsychological tests in depressive patients aged 60 or over. These findings suggested that depression may cause frontal dysfunction and frontal hypoperfusion, and that these pathophysiological changes are manifested as psychomotor retardation. We performed single photon emission computed tomography and Modified Stroop Test on 35 patients with depression aged 25-83 to investigate association of depressive symptoms and psychological tests with cerebral blood perfusion. Additionally, we divided the patients into a younger (less than 60 years old) and an older (60 or over) group to examine the effect of age. Significant correlations were found between frontal perfusion, interference measure on Modified Stroop Test, and psychomotor retardation in all patients. These correlations were also found in the younger group. There was no significant difference on frontal perfusion, interference measure of the Modified Stroop Test, and psychomotor retardation between the two groups. The present findings suggest that frontal hypoperfusion, frontal dysfunction, and psychomotor retardation were associated with one another in not only the old but also the young patients with depression.

[A case with late-onset MELAS with hallucination and delusion].

We report a 53-year-old male patient with late onset mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes(MELAS) with hallucination and delusion. The patient manifested various neurological symptoms including perceptive deafness, muscle weakness of limbs with loss of consciousness, sensory abnormalities in hands, feet and a face, abnormal sense of taste, tremor, palsy of upward eye movement and weak deep tendon reflexes prior to the psychotic episode. He was diagnosed as MELAS, because of high serum lactic acid and pyruvic acid, and the point mutation in the mitochondrial DNA 3243. SPECT imaging showed decreased perfusion in occipital cortex and thalamus. These SPECT changes improved after disappearing visual hallucination. Hallucination might be caused by delirium due to stroke-like episode. Dysfunction in the occipital cortex and thalamus might be involved with this perfusion change.