Highly porous nature of a primitive asteroid revealed by thermal imaging.

Carbonaceous (C-type) asteroids1 are relics of the early Solar System that have preserved primitive materials since their formation approximately 4.6 billion years ago. They are probably analogues of carbonaceous chondrites2,3 and are essential for understanding planetary formation processes. However, their physical properties remain poorly known because carbonaceous chondrite meteoroids tend not to survive entry to Earth's atmosphere. Here we report on global one-rotation thermographic images of the C-type asteroid 162173 Ryugu, taken by the thermal infrared imager (TIR)4 onboard the spacecraft Hayabusa25, indicating that the asteroid's boulders and their surroundings have similar temperatures, with a derived thermal inertia of about 300 J m-2 s-0.5 K-1 (300 tiu). Contrary to predictions that the surface consists of regolith and dense boulders, this low thermal inertia suggests that the boulders are more porous than typical carbonaceous chondrites6 and that their surroundings are covered with porous fragments more than 10 centimetres in diameter. Close-up thermal images confirm the presence of such porous fragments and the flat diurnal temperature profiles suggest a strong surface roughness effect7,8. We also observed in the close-up thermal images boulders that are colder during the day, with thermal inertia exceeding 600 tiu, corresponding to dense boulders similar to typical carbonaceous chondrites6. These results constrain the formation history of Ryugu: the asteroid must be a rubble pile formed from impact fragments of a parent body with microporosity9 of approximately 30 to 50 per cent that experienced a low degree of consolidation. The dense boulders might have originated from the consolidated innermost region or they may have an exogenic origin. This high-porosity asteroid may link cosmic fluffy dust to dense celestial bodies10.

Effects of Exercise Training on Mitochondrial Fatty Acid ß-Oxidation in the Kidneys of Dahl Salt-Sensitive Rats.

Exercise training (Ex) has anti-hypertensive and renal protective effects. In this study, we investigate the effects of Ex on mitochondrial fatty acid metabolism in the kidneys of Dahl salt-sensitive (Dahl-S) rats fed a high-salt (HS) diet. Eight-week-old, male Dahl-S rats were divided into three groups: (1) normal-salt diet, sedentary (NS-Sed), (2) HS diet, sedentary (HS-Sed), and (3) HS-Ex. The NS and HS groups were fed a diet containing 0.6% and 8% NaCl, respectively. The HS-Ex group performed treadmill running for 8 weeks (5 days/week; 60 min/day at 16-20 m/min, 0% gradient). Renal function and the expression of enzymes and regulators of ß-oxidation and electron transport chain (ETC) complexes were assessed. HS increased systolic blood pressure and proteinuria, and Ex ameliorated these defects. HS also reduced creatinine clearance, and Ex ameliorated it. HS reduced the renal expression of enzymes of ß-oxidation (carnitine palmitoyltransferase type I (CPTI) and acyl-CoA dehydrogenases (CADs)) and the related transcription factors peroxisome proliferator-activated receptor α (PPARα) and PPARγ-coactivator-1α (PGC-1α), and Ex restored this. HS also reduced the renal expression of enzymes in ETC complexes, and Ex restored this expression. Ex ameliorates HS-induced renal damage by upregulating enzymes involved in fatty acid ß-oxidation and ETC complexes via increases in PPAR-α and PGC-1α expressions in the kidneys of Dahl-S rats. These results suggest that Ex may have beneficial effects on HS-induced mitochondrial dysfunction in the kidney.

Effects of nighttime lavender aromatherapy on mood and physiological indices of stress in healthy young females.

[Purpose] Inhalational aromatherapy using lavender essential oil or essence is known to alleviate pain and anxiety during rehabilitation. However, the effects remain unclear in individuals who are unaware of their pain and anxiety. In this study, we investigated the effects of lavender aromatherapy during sleep in females who did not experience pain or anxiety. [Participants and Methods] The study included 24 healthy females who were randomly allocated to control and aromatherapy groups. The control group used skin patches without aroma, and the aromatherapy group used lavender aroma-infused skin patches for seven consecutive nights. Psychological and physiological indices were measured before, during, and after the intervention. [Results] The lavender aroma-infused skin patches ameliorated a negative mood associated with fatigue and anxiety. However, neither group showed a change in pulse rate and salivary cortisol concentration upon waking. Furthermore, no significant intergroup difference was observed in sleep quality. [Conclusion] Lavender aromatherapy during sleep improved a negative mood associated with fatigue and anxiety in females who did not experience pain and anxiety; however, physiological indices remained unaffected.

Effects of hyperoxia and hypoxia on the proliferation of C2C12 myoblasts.

Hyperoxic conditions are known to accelerate skeletal muscle regeneration after injuries. In the early phase of regeneration, macrophages invade the injured area and subsequently secrete various growth factors, which regulate myoblast proliferation and differentiation. Although hyperoxic conditions accelerate muscle regeneration, it is unknown whether this effect is indirectly mediated by macrophages. Here, using C2C12 cells, we show that not only hyperoxia but also hypoxia enhance myoblast proliferation directly, without accelerating differentiation into myotubes. Under hyperoxic conditions (95% O2 + 5% CO2), the cell membrane was damaged because of lipid oxidization, and a disrupted cytoskeletal structure, resulting in suppressed cell proliferation. However, a culture medium containing vitamin C (VC), an antioxidant, prevented this lipid oxidization and cytoskeletal disruption, resulting in enhanced proliferation in response to hyperoxia exposure of ≤4 h/day. In contrast, exposure to hypoxic conditions (95% N2 + 5% CO2) for ≤8 h/day enhanced cell proliferation. Hyperoxia did not promote cell differentiation into myotubes, regardless of whether the culture medium contained VC. Similarly, hypoxia did not accelerate cell differentiation. These results suggest that regardless of hyperoxia or hypoxia, changes in oxygen tension can enhance cell proliferation directly, but do not influence differentiation efficiency in C2C12 cells. Moreover, excess oxidative stress abrogated the enhancement of myoblast proliferation induced by hyperoxia. This research will contribute to basic data for applying the effects of hyperoxia or hypoxia to muscle regeneration therapy.

Dysphagia worsens short-term outcomes in patients with acute exacerbation of heart failure.

Dysphagia, defined as a dysfunction in any stage or process of eating, is common in patients with acute exacerbation of heart failure (HF). In some diseases, dysphagia worsens in-hospital mortality, length of hospital stay, and discharge disposition. However, it remains unclear whether dysphagia is associated with poor short-term outcomes in HF patients. The objective of the present study was to determine whether dysphagia affects short-term outcomes in patients with acute exacerbation of HF. A total of 327 patients hospitalized with acute exacerbation of HF were eligible for the study. Patients were divided into a dysphagia group (DG) or a non-dysphagia group (NDG) based on results of the functional oral intake scale (FOIS), which evaluates a patient's ability of eating and swallowing. FOIS is a 7-point scale, with a level of ≤ 5 indicating dysphagia. Following the withdrawal of 16 patients, short-term outcomes such as in-hospital mortality, length of hospital stay, and discharge disposition, of 311 patients were analyzed. All indexes of short-term outcomes were significantly worse in the DG than in the NDG. After propensity score matching, which was performed to adjust for baseline characteristics such as age, sex, height, weight, body mass index, medical history, complications, HF severity, ejection fraction, and biochemical data excluding nutritional status, all short-term outcomes remained significantly worse in the DG than in the NDG. Multivariate analysis showed that FOIS was an independent predictor of in-hospital survival, length of hospital stay, and discharge to home. The present study suggested that dysphagia affected short-term outcomes in patients with acute exacerbation of HF. Therefore, early detection and intervention of dysphagia in HF patients are important.

Dysphagia Hinders Hospitalized Patients with Heart Failure from Being Discharged to Home.

Dysphagia, defined as a dysfunction in any stage or process of eating, is common among heart failure (HF) patients. In some diseases state, dysphagia hinders patients from being discharged to home. However, it remains unclear whether dysphagia affects discharge disposition of HF patients. This study aimed to identify the impact of dysphagia on discharge disposition of HF patients. A total of 323 patients, hospitalized with acute exacerbation of HF, were eligible for the study (excluding patients who lived at nursing care facilities before admission). Following the withdrawal of 37 patients, a total of 286 patients were analyzed. Dysphagia was determined using the functional oral intake scale (FOIS), which evaluates a patient's ability to swallow. The FOIS is a 7-point scale, with a level of ≤ 5 indicating dysphagia. Of the 286 patients analyzed, 231 (80.8%) were discharged to home, and 55 were discharged to nursing care facilities or rehabilitation hospitals (non-home). FOIS level was significantly lower, and dysphagia incidence was significantly higher among patients discharged to non-home than among those discharged to home. Multivariate analysis showed that FOIS level was an independent predictor of discharge disposition. Additionally, after propensity score matching, which was performed to adjust for baseline characteristics, FOIS level remained significantly lower in patients discharged to non-home than in those discharged to home. In conclusion, dysphagia hinders patients hospitalized with HF from being discharged to home. We conclude that evaluating dysphagia and its severity on admission is useful for predicting discharge disposition in patients hospitalized with HF.

Angiotensin II upregulates CYP4A isoform expression in the rat kidney through angiotensin II type 1 receptor.

Angiotensin II (AngII) stimulates the renal production and release of 20-hydroxyeicosatetraenoic acids (20-HETE), which is a major metabolite of arachidonic acid catalyzed by CYP4A isoforms. However, the effects of AngII on CYP4A isoform expression in the kidney and its mechanism remains unclear. To clarify the regulation of CYP4A isoform expression by AngII, we examined the chronic effects of AngII and AngII type 1 receptor (AT1-R) blockade on CYP4A isoform expression. Sprague-Dawley rats were infused with vehicle or AngII for 1 week, and the AngII-infused rats were also treated with or without the AT1-R blocker, candesartan. AngII increased CYP4A isoform protein expression in the renal cortex (CO) and outer medulla (OM) in a dose-dependent manner, and candesartan inhibited the AngII-increased CYP4A expression in a dose-dependent manner. AngII increased the CYP4A isoform mRNA expression in the CO and OM, and candesartan inhibited AngII-increased CYP4A isoform mRNA expression. These results indicated that AngII chronically increased the CYP4A isoform expression in the rat kidney. The AngII-induced CYP4A isoform expression was mediated by AT1-R.

Six-Month Lower Limb Aerobic Exercise Improves Physical Function in Young-Old, Old-Old, and Oldest-Old Adults.

The effect of aerobic exercise on physical function and mental health in various adult age groups (young-old, 65-74; old-old, 75-84; oldest-old, ≥ 85 years) is unclear. The aim of this study was to investigate the effects of the Kohzuki Exercise Program (KEP) on physical function and mental health in these age groups. The KEP consisted of 40-min supervised sessions 3 times per week for 6 months as follows: 5 min of warm-up, 30 min of lower limb aerobic exercise, and 5 min of cool-down. A total of 50 participants (22 young-old, 20 old-old, and 8 oldest-old) who participated in the KEP completed at least 88% of the sessions. In statistical analysis, 3 (group: oldest-old, old-old, young-old) × 2 (time: baseline and after 6 months) analyses of variance were used to determine if there were significant main and interaction effects. Significant interactions were probed using the post-hoc paired t test. The Short Physical Performance Battery (SPPB) score showed significant group × time interactions after 6 months (p = 0.031). In the post-hoc test, oldest-old (p < 0.001), old-old (p < 0.001), and young-old (p < 0.01) groups had significantly better physical function after 6 months. However, none of the mental health measures showed group × time interactions at 6-month. Our results suggest that a 6-month KEP led to improved physical function in oldest-old, old-old, and young-old adults. The KEP was effective for oldest-old adults in particular. The KEP exhibits good adherence, making it suitable for a wide age range in society.

Evaluation of bilateral force deficit in shoulder flexion using a handheld dynamometer in healthy subjects.

[Purpose] This study aimed to develop a simple, inexpensive, and accurate method for measuring the strength of shoulder flexion (Experiment 1) and evaluate the bilateral force deficit in shoulder flexion (Experiment 2) in healthy subjects. [Subjects and Methods] In Experiment 1, maximal voluntary contractions (MVCs) in isometric shoulder flexion were measured on both sides using an isometric dynamometer (ID) and a hand-grip dynamometer (HGD), as an alternative dynamometer, in six subjects. In Experiment 2, bilateral force deficit was evaluated using HGD in 21 subjects who performed unilateral and bilateral MVCs in isometric flexions of the shoulder. The peak value of electromyography (PVE) in the lateral head of the biceps brachii and anterior deltoid was measured during MVCs. [Results] In Experiment 1, ID and HGD showed almost similar coefficients of variation. A strong positive correlation was found between the values obtained using the two methods. In Experiment 2, the bilateral force deficit in shoulder flexion associated with a reduced PVE (‒10.9%) was found in 85.7% of subjects. [Conclusion] The reproducibility of measurements was similar between ID and HGD. HGD could evaluate the bilateral force deficit in shoulder flexion and is a practical tool for measuring shoulder strength.

Arterial Stiffness Measured with the Cuff Oscillometric Method Is Predictive of Exercise Capacity in Patients with Cardiac Diseases.

Arterial stiffness is widely used in assessing arteriosclerosis in the background of increased cardiovascular events. Arteriosclerosis also causes reduction in exercise capacity, which is a most important prognostic factor in patients with cardiovascular disease; however, data on the association between arterial stiffness and exercise capacity are limited. Therefore, a simple and noninvasive measurement of arterial stiffness that reflects the central circulation and exercise capacity is needed. The arterial velocity pulse index (AVI) is a parameter of arterial stiffness measurable with the cuff oscillometric method; however, the clinical utility of this method is unclear. We aimed to evaluate the trend of AVI in patients with coronary artery disease (CAD), and the association between AVI and exercise capacity. A cross-sectional study of 116 patients with cardiac disease (34 CAD and 82 non-CAD patients) was performed. Non-CAD patients were those with any cardiac diseases who did not have proven CAD. The results showed that the AVI was significantly higher in CAD patients than non-CAD patients (P < 0.05, analysis of covariance). The AVI was inversely correlated with peakVO2 (r = -0.239, P < 0.05) and was a significant explanatory variable for peakVO2 in stepwise regression analysis (ß = -14.62, t = -2.5, P < 0.05). These results indicate that the AVI is strongly associated with CAD and predictive of the exercise capacity in patients with cardiac diseases. We, therefore, propose that the cuff oscillometric method is clinically useful in evaluating arterial stiffness in patients with cardiac diseases, especially CAD.