A 12-week physical and cognitive exercise program can improve the efficiency of brain activation during cognitive tasks in older adults, which is associated with improvements in memory and executive function.

BackgroundThe anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task.Methodology/Principal FindingsSixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial.Conclusions/SignificanceThe results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing.

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The long-term clinical course, prognosis, and optimal management of symptoms and conditions after the acute phase of coronavirus disease 2019 remain to be elucidated. The purpose of this study was to clarify the characteristics of patients referred to a COVID-19 aftercare (CAC) clinic established at a tertiary academic hospital in Japan. MethodsThis study was a descriptive case series study. All patients who visited the CAC clinic between February 15 and September 17 in 2021 were included. Patients' background, chief complaints, and clinical courses after the onset of COVID-19 were described. ResultsA total of 87 Japanese patients (median age, 40.0 years; interquartile range [IQR], 26.5-53.0 years; 52.9% women) were referred to the CAC clinic. The median interval between the onset of COVID-19 and the visit to the clinic was 79.0 (IQR, 52.5-112.0) days. Referral sources were hospitals (36 patients), clinics (47 patients), a local healthcare center (3 patients), and other (1 patient). The most common chief complaint was general fatigue (50.4%) followed by dysosmia (28.7%), dysgeusia (26.4%), hair loss (18.4%), headache (17.2%), dyspnea (16.1%), and dyssomnia (13.1%). Respiratory symptoms were common in the early stages of the disease but were less common as the chief complaints when visiting the clinic. On the other hand, neurological, psychiatric, and extremity symptoms were predominant one month after the onset of COVID-19. ConclusionsRegardless of the severity in the acute phase, patients visiting our CAC clinic suffered from a variety of symptoms. General physicians skilled in using a comprehensive approach would be optimal to see patients with such complex symptoms.

The prevalence of high scorers is comparable to those reported in other countries. The use of the questionnaire was helpful in drawing the attention of mothers and health care professionals to issues of mental health.

BackgroundInherited retinal degeneration (IRD) refers to a heterogenous group of progressive diseases that cause death of photoreceptor cells and subsequent vision loss. These diseases often affect the peripheral retina, objective evaluation of which has been difficult until recently. Fundus autofluorescence (FAF) is a non-invasive retinal imaging technique that depicts the distribution of intrinsic fluorophores in the retina. The primary source of retinal autofluorescence is lipofuscin, which is contained in the retinal pigment epithelium (RPE). Excessive accumulation of lipofuscin and a window defect attributable to loss of photoreceptor pigment result in increased FAF whereas loss of the RPE results in decreased FAF. These changes can be seen during the course of IRD.MainbodyWhile conventional modalities are limited in their angle of view, recent technologic advances, known as wide-field and ultra-widefield FAF imaging, have enabled visualization of the far peripheral retina. Although clinical application of this technique in patients with IRD is still in its infancy, some studies have already indicated its usefulness. For example, an area with decreased FAF correlates well with a visual field defect in an eye with retinitis pigmentosa (RP) or cone-rod dystrophy. An abnormal FAF pattern may help in the diagnosis of IRD and associated diseases. In addition, female carriers of X-linked RP and female choroideremia show characteristic appearance. Conversely, absence of abnormal FAF despite severe retinal degeneration helps differentiation of cancer-associated retinopathy.ConclusionThis paper reviews the principles of FAF, wide-field imaging, and findings in specific diseases. Wide-field imaging, particularly wide-field FAF, will provide further information for the characteristics, prognosis, and pathogenesis of IRD.

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Background: Intestinal absorption of levofloxacin (LFX) is decreased by the concomitant administration of antacids due to the formation of insoluble chelate complexes with various metal cations. Methods: The following four ester prodrugs of LFX—cilexetil ester (LFX-CLX), medoxomil ester (LFX-MDX), ethoxycarbonyl 1-ethyl hemiacetal ester (LFX-EHE) and pivaloyloxymethyl ester (LFX-PVM) — were synthesized. Then, the lipophilicity, in vitro chelate formation with aluminum chloride (AlCl3), chemical and enzymatic stability, minimum inhibitory concentrations (MICs) against some bacteria, and the efficacy in preventing chelate formation of prodrugs with aluminum hydroxide (Al(OH)3) in rabbits were evaluated. Results: The synthesized ester prodrugs of LFX exhibited high purity and higher lipophilicities than LFX depending on the ester moieties. MICs of the prodrugs against S. aureus, E. coli, and P. aeruginosa were more than 10 times higher than those of LFX. Prodrugs were stable chemically but unstable enzymatically and generated LFX in biological specimens. When AlCl3 solution was mixed with LFX solution in vitro, insoluble chelate complex was formed immediately. In rabbits, co-administration of Al(OH)3 with LFX reduced the oral bioavailability of LFX by approximately 40%. In contrast, no precipitation was observed when AlCl3 solution was mixed with each prodrug solution in vitro, and co-administration of Al(OH)3 exerted no significant effect on the oral bioavailability of LFX when each prodrug was administered in rabbits. Conclusion: The ester prodrug approach of LFX could be a feasible strategy for avoiding chelate formation with aluminum ion in vivo.