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The early detection of cognitive decline in older adults is crucial for preventing dementia. This mini-review focuses on electroencephalography (EEG) markers of early dementia-related precursors, including subjective cognitive decline, subjective memory complaints, and cognitive frailty. We present recent findings from EEG analyses identifying high dementia risk in older adults, with an emphasis on conditions that precede mild cognitive impairment. We also cover event-related potentials, quantitative EEG markers, microstate analysis, and functional connectivity approaches. Moreover, we discuss the potential of these neurophysiological markers for the early detection of cognitive decline as well as their correlations with related biomarkers. The integration of EEG data with advanced artificial intelligence technologies also shows promise for predicting the trajectory of cognitive decline in neurodegenerative disorders. Although challenges remain in its standardization and clinical application, EEG-based approaches offer non-invasive, cost-effective methods for identifying individuals at risk of dementia, which may enable earlier interventions and personalized treatment strategies.

Abstract Background and Aim We evaluated whether diffusion kurtosis and tensor imaging (DKI/DTI) could reveal microstructural alterations in the brains of patients with functional gastrointestinal disorders (FGIDs), and whether imaging findings were correlated with health‐related quality of life (HRQOL). Methods Twelve patients with FGIDs fulfilling the Rome IV criteria, and seven healthy controls were examined using a 3 T magnetic resonance (MR) scanner. Tract‐based spatial statistics and regions of interest analyses were performed to compare the mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) between patients with FGIDs versus controls. HRQOL was assessed in patients with FGIDs using the eight‐item short form of the Medical Outcome Study Questionnaire (SF‐8) and the Gastrointestinal Symptom Rating Scale. Results Patients with FGIDs had extensive, widespread regions of reduced MD in the white matter in comparison with healthy controls, whereas no significant differences were observed in MK and FA. No significant differences in deep gray matter for the MK, FA, and MD values were observed between patients with FGIDs and controls. In patients with FGIDs, the FA values in the globus pallidus had a significant and negative correlation with SF‐8 (a mental component summary) (r = −0.797, P = 0.01 uncorrected for multiple comparisons). Conclusions DKI/DTI can help identify microstructural white matter alterations in patients with FGIDs. The FA values in the globus pallidus may be useful for a severity assessment of FGIDs.

Background: While type 2 diabetes (T2D) is a major risk for ischemic stroke, the associated vessel wall characteristics remain essentially unknown. This study aimed to clarify intracranial vascular changes on three-dimensional vessel wall imaging (3D-VWI) using fast spin echo by employing 7Tesla (7T) magnetic resonance imaging (MRI) in T2D patients without advanced atherosclerosis as compared to healthy controls. Methods: In 48 T2D patients and 35 healthy controls, the prevalence of cerebral small vessel diseases and intracranial plaques were evaluated by 3D-VWI with 7T MRI. Results: The prevalence rate of lacunar infarction was significantly higher in T2D than in controls (n = 8 in T2D vs. n = 0 in control, p = 0.011). The mean number of intracranial plaques in both anterior and posterior circulation of each subject was significantly larger in T2D than in controls (2.23 in T2D vs. 0.94 in control, p < 0.01). In T2D patients, gender was associated with the presence of intracranial plaques. Conclusion: This is the first study to demonstrate the high prevalence of intracranial plaque in T2D patients with neither confirmed atherosclerotic disease nor symptoms by performing intracranial 3D-VWI employing 7TMRI. Investigation of intracranial VWI with 7T MRI is expected to provide novel insights allowing early intensive risk management for prevention of ischemic stroke in T2D patients.

Among the several functions of the nasal cavity, temperature and humidity adjustments are important for preserving the trachea and lungs. The functions of the nasal cavity have been clarified in experiments investigating the conditions in the nasal cavity. However, the difficulties of noninvasive measurements have rendered nasal cavity simulations an attractive alternative. Data are readily obtained from a simulated result. In this study, airflow, temperature, and humidity transfer in the human nasal cavity were investigated in a nasal cavity wall model of temperature and humidity transport. The simulated result was verified by comparison with experimental data. A reasonable agreement was attained between experimental data and a model incorporating the latent heat effect. The model simulates heat and water exchange in the nasal cavity. In all cases, the temperature and humidity of the inhaled air were adjusted to suitable physiological values. Temperature and humidity gradients were highest at the front of the nasal cavity. The influence of latent heat was clarified by comparing simulation results with and without latent heat under several inhaled air conditions. In the hot-humid inhaled air case, temperature in the Kiesselbach area was increased by latent heat of condensation, and relative humidity declined. In the other inhaled air cases, the temperature in the Kiesselbach area was decreased by latent heat of evaporation, while relative humidity increased. Latent heat effect was particularly influential in the hot inhaled air case.

We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD) with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved "Out of Africa" to explore the more severe climates of Eurasia.

The nasal cavity performs several important functions for the inhaled air, such as temperature and humidity adjustments. Although it is necessary to obtain velocity, temperature, and humidity distributions during inhalation in order to understand the nasal cavity's functions, it is difficult to measure them noninvasively in the nasal cavity. Therefore, we have continued to study nasal flow simulation with heat and humidity transport. In such a simulation, the governing equations include a continuum equation and the equations describing momentum, energy, and water transport. The temperature and humidity of the inhaled air are adjusted by heat and water exchange on the nasal cavity wall's surface. Therefore, in the simulation, these roles of the wall in the energy and water transport equations were included as the boundary conditions. Although in related studies of nasal flow simulation with heat and humidity transport, the nasal cavity wall's surface temperature and humidity were constant, here they were treated as degrees of using Newton's cooling law. A flow including temperature and humidity in a realistic human nasal cavity shape was simulated. The simulation results agreed well with the measurements reported by Keck at al. Therefore, this study concludes that our model can simulate the heat and humidity exchange occurring in the nasal cavity. In addition, it was found that the temperature and humidity adjustment functions worked effectively in the front and narrow regions of the nasal cavity.

Several qualitative features distinguish bipedal from quadrupedal locomotion in mammals. In this study we show quantitative differences between quadrupedal and bipedal gait in the Japanese monkey in terms of gait patterns, trunk/hindlimb kinematics, and electromyographic (EMG) activity, obtained from 3 macaques during treadmill walking. We predicted that as a consequence of an almost upright body axis, bipedal gait would show properties consistent with temporal and spatial optimization countering higher trunk/hindlimb loads and a less stable center of mass (CoM). A comparatively larger step width, an ~9% longer duty cycle, and ~20% increased relative duration of the double-support phase were all in line with such a strategy. Bipedal joint kinematics showed the strongest differences in proximal, and least in distal, hindlimb joint excursions compared with quadrupedal gait. Hindlimb joint coordination (cyclograms) revealed more periods of single-joint rotations during bipedal gait and predominance of proximal joints during single support. The CoM described a symmetrical, quasi-sinusoidal left/right path during bipedal gait, with an alternating shift toward the weight-supporting limb during stance. Trunk/hindlimb EMG activity was nonuniformally increased during bipedal gait, most prominently in proximal antigravity muscles during stance (up to 10-fold). Non-antigravity hindlimb EMG showed altered temporal profiles during liftoff or touchdown. Muscle coactivation was more, but muscle synergies less, frequent during bipedal gait. Together, these results show that behavioral and EMG properties of bipedal vs. quadrupedal gait are quantitatively distinct and suggest that the neural control of bipedal primate locomotion underwent specific adaptations to generate these particular behavioral features to counteract increased load and instability. NEW & NOTEWORTHY Bipedal locomotion imposes particular biomechanical constraints on motor control. In a within-species comparative study, we investigated joint kinematics and electromyographic characteristics of bipedal vs. quadrupedal treadmill locomotion in Japanese macaques. Because these features represent (to a large extent) emergent properties of the underlying neural control, they provide a comparative, behavioral, and neurophysiological framework for understanding the neural system dedicated to bipedal locomotion in this nonhuman primate, which constitutes a critical animal model for human bipedalism. [ABSTRACT FROM AUTHOR]

The nasal passages mainly adjust the temperature and humidity of inhaled air to reach the alveolar condition required in the lungs. By contrast to most other non-human primates, macaque monkeys are distributed widely among tropical, temperate and subarctic regions, and thus some species need to condition the inhaled air in cool and dry ambient atmospheric areas. The internal nasal anatomy is believed to have undergone adaptive modifications to improve the airconditioning performance. Furthermore, the maxillary sinus (MS), an accessory hollow communicating with the nasal cavity, is found in macaques, whereas it is absent in most other extant Old World monkeys, including savanna monkeys. In this study, we used computational fluid dynamics simulations to simulate the airflow and heat and water exchange over the mucosal surface in the nasal passage. Using the topology models of the nasal cavity with and without the MS, we demonstrated that the MS makes little contribution to the airflow pattern and the air-conditioning performance within the nasal cavity in macaques. Instead, the inhaled air is conditioned well in the anterior portion of the nasal cavity before reaching the MS in both macaques and savanna monkeys. These findings suggest that the evolutionary modifications and coetaneous variations in the nasal anatomy are rather independent of transitions and variations in the climate and atmospheric environment found in the habitats of macaques. [ABSTRACT FROM AUTHOR]

Background. Ballet dance involves extreme range of motion (ROM) in the hip joint. This ROM can cause injuries including labral strain, tears, and subluxation episodes. Case Presentation. A 69-year-old female classical ballet dance instructor presented bilateral hip pain. The plain radiograph showed end-stage osteoarthritic change in the bilateral hip. She could neither dance nor perform daily activities. Bilateral hybrid total hip arthroplasty (THA) was performed. After surgery, she was able to demonstrate the split position on the floor as an active classical ballerina. The plain radiograph was taken in the split position, and the radiograph did not show any characteristics of impingement or subluxation of the femoral head. Conclusion. She was able to continue working as a classical ballet instructor after bilateral THA. Additionally, any characteristics of impingement or subluxation of the femoral head were not revealed in the postoperative radiograph in the split position.

Background. A stress fracture of the second metatarsal base in soccer players is extremely rare. In this case study, we report a nonunion of a stress fracture at the base of the second metatarsal in a female soccer player who had persistent pain despite continued conservative treatment, who then was treated with the bridging plate fixation technique. Case Report. A 19-year-old female college soccer player complained of pain on the dorsum of her right midfoot during a game without history of trauma and was conservatively treated for 6 months. Radiographic examination showed an oblique fracture with small bone fragment at the proximal base of the second metatarsal and computed tomography demonstrated sclerotic change around the fracture site. We diagnosed her with nonunion of a stress fracture at the base of the second metatarsal and performed operative treatments using autogenous cancellous iliac bone grafting and plate fixation bridging a second metatarsal and medial cuneiform with a locking plate. At 4 months after the initial surgery, she was able to return to playing soccer at preinjury level without complications or pain. Conclusion. We report a rare case of nonunion of a stress fracture at the base of the second metatarsal in a female soccer player without underlying diseases. Surgical treatment was applied, because the conservative treatment was ineffective for 6 months and led to nonunion. The plate fixation technique bridging the second metatarsal and medial cuneiform was a useful option to attain the bone fusion for small fracture fragment for a treatment of nonunion of a stress fracture at the base of the second metatarsal.