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Physical exercise, even stress-free very-light-intensity exercise such as yoga and very slow running, can have beneficial effects on executive function, possibly by potentiating prefrontal cortical activity. However, the exact mechanisms underlying this potentiation have not been identified. Evidence from studies using pupillometry demonstrates that pupil changes track the real-time dynamics of activity linked to arousal and attention, including neural circuits from the locus coeruleus to the cortex. This makes it possible to examine whether pupil-linked brain dynamics induced during very-light-intensity exercise mediate benefits to prefrontal executive function in healthy young adults. In this experiment, pupil diameter was measured during 10 min of very-light-intensity exercise (30% V˙o 2peak ). A Stroop task was used to assess executive function before and after exercise. Prefrontal cortical activation during the task was assessed using multichannel functional near-infrared spectroscopy (fNIRS). We observed that very-light-intensity exercise significantly elicited pupil dilation, reduction of Stroop interference, and task-related left dorsolateral prefrontal cortex activation compared with the resting-control condition. The magnitude of change in pupil dilation predicted the magnitude of improvement in Stroop performance. In addition, causal mediation analysis showed that pupil dilation during very-light-intensity exercise robustly determined subsequent enhancement of Stroop performance. This finding supports our hypothesis that the pupil-linked mechanisms, which may be tied to locus coeruleus activation, are a potential mechanism by which very light exercise enhances prefrontal cortex activation and executive function. It also suggests that pupillometry may be a useful tool to interpret the beneficial impact of exercise on boosting cognition., Competing Interests: Declaration of Competing Interest The authors do not declare any competing interests., (Copyright © 2023. Published by Elsevier Inc.)

Although it has been hypothesized that moderate to vigorous exercise immediately modulates cognition via ascending arousal system activation, such activation during very-light to light exercise has remained uncertain. Here, we aimed to uncover the exact exercise intensity necessary for ascending arousal system activation using pupillometry. The pupil diameter, psychological arousal, and ventilation during graded exercise of 26 young males were analyzed based on %[Formula: see text]. Pupils dilated with very-light exercise compared to rest, stabilized, and then drastically increased again with moderate exercise and above. Pupil dilation with very-light exercise was positively correlated with increases in psychological arousal. Thus, we have shown that there are two phases of pupil dilation during graded exercise: one with very-light exercise coinciding with psychological arousal response, and the other with moderate exercise or above similar to the ventilation increase pattern. This unique pupil dilation pattern provides physiological evidence of ascending arousal system activation with very-light exercise., (© 2022. The Author(s).)

Infection from fluoroquinolone-resistant Enterobacteriaceae is an increasing health problem worldwide. In the present study, we developed a pyrosequencing-based high-throughput method for analyzing the nucleotide sequence of the quinolone resistance-determining regions (QRDRs) of gyrA and parC. By using this method, we successfully determined the QRDR sequences of 139 out of 140 clinical Escherichia coli isolates, 28% of which were nonsusceptible to ciprofloxacin. Sequence results obtained by the pyrosequencing method were in complete agreement with those obtained by the Sanger method. All fluoroquinolone-resistant isolates (n = 35; 25%) contained mutations leading to three or four amino acid substitutions in the QRDRs. In contrast, all isolates lacking a mutation in the QRDR (n = 81; 57%) were susceptible to ciprofloxacin, levofloxacin, and nalidixic acid. The qnr determinants, namely, the qnrA, qnrB, and qnrS genes, were not detected in the isolates, and the aac(6')-Ib-cr gene was detected in 2 (1.4%) of the isolates. Multilocus sequence typing of 34 randomly selected isolates revealed that sequence type 131 (ST131) (n = 7; 20%) is the most prevalent lineage and is significantly resistant to quinolones (P < 0.01). The genetic background of quinolone-susceptible isolates seemed more diverse, and interestingly, neighboring STs of ST131 in the phylogenetic tree were all susceptible to ciprofloxacin. In conclusion, our investigation reveals the relationship between fluoroquinolone resistance caused by mutations of QRDRs and the population structure of clinical extraintestinal E. coli isolates. This high-throughput method for analyzing QRDR mutations by pyrosequencing is a powerful tool for epidemiological studies of fluoroquinolone resistance in bacteria.

A 47-year-old woman was admitted to hospital with severe Legionella pneumonia. The respiratory symptoms improved dramatically and the X-rays revealed a decrease in the diffuse chest infiltrates after treatment with erythromycin and rifampicin. However, chest CT scans showed that the reticulonodular opacities persisted for several weeks after the onset of pneumonia. Two months after admission, the chest X-rays showed the progression of small nodules in both lungs and there was increasing respiratory distress. A diagnosis of miliary tuberculosis was confirmed. The present case should alert physicians to this potentially confusing combination of respiratory pathogens.

Background: Angiogenesis is a prerequisite for airway remodeling in bronchial asthma. Several growth factors may play important roles in inflammation and angiogenesis through effects on inflammatory cell infiltration or neovascularization., Objective: We sought to compare bronchial vascularity and expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and angiogenin in bronchial biopsy specimens from asthmatic and healthy control subjects., Methods: Bronchial biopsy specimens were obtained from 16 asthmatic subjects and 9 normal control subjects. The number of vessel profiles and the vascular area per unit area on a histologic section were estimated by using computerized image analysis after staining for type IV collagen in vessel walls. Numbers of VEGF+, bFGF+, and angiogenin+ cells were determined by means of immunoreactivity., Results: The airways of asthmatic subjects had significantly more vessels (P < .05) and greater vascular area (P < .001) than that observed in control subjects. Asthmatic subjects exhibited higher VEGF and bFGF and angiogenin immunoreactivity in the submucosa than did control subjects (P < .001, respectively). Significant correlations were detected between the vascular area and the numbers of angiogenic factor-positive cells (VEGF: rs = 0.93, P < .001; bFGF: rs = 0.83, P < .001; angiogenin: rs = 0.88, P < .001) within the asthmatic airways. Furthermore, the degree of vascularity was inversely correlated with airway caliber and airway responsiveness. Colocalization analysis revealed that the angiogenic factor-positive cells were CD34+ cells, eosinophils, and macrophages., Conclusion: Our results suggest that increased vascularity of the bronchial mucosa in asthmatic subjects is closely related to the expression of angiogenic factors, which may then contribute to the pathogenesis of asthma.

A 51 year-old man fitted with a dental prosthesis was hospitalized with buccal swelling, fever and chest pain. Laboratory data showed marked inflammatory changes, and chest radiography and CT scanning revealed small nodular shadows within the lung. A diagnosis of multiple lung abscesses secondary to a buccal abscess possibly caused by the prosthesis was made from needle aspiration biopsies of the lung nodules and of a buccal lesion. Klebsiella pneumoniae was isolated from these lesions and from a blood culture. The patient was successfully treated with antibiotics and by surgical drainage of the buccal abscess. It is important to note that the patient was immunodeficient at the time as a result of diabetes and alcohol intoxication.