Determinants of Anaerobic Threshold at Each Stage of Renal Dysfunction in Patients With Heart Disease.

Patients with heart disease have a low anaerobic threshold (AT), and the determinants of AT may differ, depending on the severity of renal dysfunction. This study aimed to verify the determinants of AT for each stage of renal function in patients with heart disease. We consecutively enrolled 250 patients with heart disease who underwent cardiopulmonary exercise testing in our institution. The patients were divided into 3 groups by their estimated glomerular filtration rate (eGFR): <45, 45 to 59, and ≥60 ml/min/1.73 m2. A multivariate linear regression analysis was performed to evaluate the independent determinants of AT for each group. In total, 201 patients were analyzed. AT decreased with the deterioration of renal function (eGFR <45, 10.9 ± 2.1 vs eGFR 45 to 59, 12.4 ± 2.5 vs eGFR ≥60, 14.0 ± 2.6 ml/min/kg, p <0.001). In the eGFR <45 group, left ventricular ejection fraction and hemoglobin were significantly associated with AT (ß = 0.427, p = 0.006 and ß = 0.488, p = 0.002, respectively). In the eGFR 45 to 59 and ≥60 groups, ΔPETO2 (end-tidal oxygen partial pressure from rest to AT) showed a significant association with AT (ß = 0.576, p <0.001 and ß = 0.308, p = 0.003, respectively). The determinants of AT depended on the stage of renal dysfunction in patients with heart disease. In conclusion, in the eGFR <45 group, the determinants of AT were left ventricular ejection fraction and hemoglobin, whereas in the eGFR 45 to 59 and eGFR ≥60 groups, the determinant of AT was ΔPETO2.

End-tidal oxygen partial pressure is a strong prognostic predictive factor in patients with cardiac disease.

BACKGROUND: Cardiopulmonary exercise testing (CPET) variables represent central and peripheral factors and combined factors in the pathology of patients with cardiac disease. The difference in end-tidal oxygen partial pressure from resting to anaerobic threshold (ΔPETO2 ) may represent predominantly peripheral factors. This study aimed to verify the prognostic significance of ΔPETO2 for major adverse cardiac and cerebrovascular events (MACCE) in cardiac patients, including comparison with the minute ventilation-carbon dioxide production relationship (VE/VCO2 slope), and peak oxygen uptake (VO2 ). METHODS: In total, 185 patients with cardiac disease who underwent CPET were consecutively enroled in this retrospective study. The primary endpoint was 3-year MACCE. The ability of ΔPETO2 , VE/VCO2 slope, and peak VO2 to predict MACCE was examined. RESULTS: Optimal cut-off values for predicting MACCE were 2.0 mmHg for ΔPETO2 (area under the curve [AUC]: 0.829), 29.8 for VE/VCO2 slope (AUC: 0.734), and 19.0 mL/min/kg for peak VO2 (AUC: 0.755). The AUC of ΔPETO2 was higher than those of VE/VCO2 slope and peak VO2 . The MACCE-free survival rate was significantly lower in the ΔPETO2 ≤ 2.0 group versus the ΔPETO2 > 2.0 group (44.4% vs. 91.2%, p < 0.001). ΔPETO2 ≤ 2.0 was an independent predictor of MACCE after adjustment for age and VE/VCO2 slope (hazard ratio [HR], 7.28; p < 0.001) and after adjustment for age and peak VO2 (HR, 6.52; p < 0.001). CONCLUSION: ΔPETO2 was a strong predictor of MACCE independent of and superior to VE/VCO2 slope and peak VO2 in patients with cardiac disease.

Usability and acceptance of crowd-based early warning of harmful algal blooms.

Crowdsensing has become an alternative solution to physical sensors and apparatuses. Utilizing citizen science communities is undoubtedly a much cheaper solution. However, similar to other participatory-based applications, the willingness of community members to be actively involved is paramount to the success of implementation. This research investigated factors that affect the continual use intention of a crowd-based early warning system (CBEWS) to mitigate harmful algal blooms (HABs). This study applied the partial least square-structural equation modeling (PLS-SEM) using an augmented technology acceptance model (TAM). In addition to the native TAM variables, such as perceived ease of use and usefulness as well as attitude, other factors, including awareness, social influence, and reward, were also studied. Furthermore, the usability factor was examined, specifically using the System Usability Scale (SUS) score as a determinant. Results showed that usability positively affected the perceived ease of use. Moreover, perceived usefulness and awareness influenced users' attitudes toward using CBEWS. Meanwhile, the reward had no significant effects on continual use intention.

Older phase 2 cardiac rehabilitation patients engaged in gardening maintained physical function during the COVID-19 pandemic.

This study aimed to clarify the effects of gardening on hemodynamic response, rating of perceived exertion (RPE) during exercise, and body weight in patients in whom phase 2 cardiac rehabilitation (CR) was interrupted due to the Coronavirus disease 2019 (COVID-19) pandemic. Among 76 outpatients participating in consecutive phase 2 CR in both periods from March to April and June to July 2020, which were before and after CR interruption, respectively, at Sanda City Hospital were enrolled. The inclusion criterion was outpatients whose CR was interrupted due to COVID-19. Patients under the age of 65 were excluded. We compared the data of hemodynamic response and RPE during exercise on the last day before interruption and the first day after interruption when aerobic exercise was performed at the same exercise intensity in the gardener group and the non-gardener group. Forty-one patients were enrolled in the final analysis. After CR interruption, the gardener group did not show any significant difference in all items, whereas the non-gardener group experienced significant increase in HR (Peak) (p = 0.004) and worsening of the Borg scale scores for both dyspnea and lower extremity fatigue (p = 0.039 and p = 0.009, respectively). Older phase 2 CR patients engaged in gardening did not show any deterioration in hemodynamic response or RPE during exercise, despite CR interruption and refraining from going outside. Gardening may be recommended as one of the activities that can maintain or improve physical function in older phase 2 CR patients during the COVID-19 pandemic.

Relationship of end-tidal oxygen partial pressure to the determinants of anaerobic threshold in post-myocardial infarction patients.

The anaerobic threshold (AT), obtained during cardiopulmonary exercise testing (CPET), is an important prognostic measure and can be used to develop an exercise prescription in patients after a myocardial infarction (post-MI). The purpose of this study was to examine the central and peripheral determinants of AT in post-MI patients end-tidal oxygen partial pressure (PETO2) measures. We performed cardiopulmonary exercise testing (CPET) on 148 consecutively enrolled post-MI patients to determine PETO2 measured at the AT (AT PETO2) and ΔPETO2 (difference between resting PETO2 and AT PETO2). We subsequently investigated the relationship between these measures of PETO2 and the individual AT for each patient. Multivariate linear regression analysis indicated that AT PETO2 and ΔPETO2 were independently and significantly associated with the AT (ß = -0.344, p < 0.001 and ß = 0.228, p < 0.001, respectively). Furthermore, the independent factors of AT PETO2 were left ventricular ejection fraction (p = 0.005), resting ventilatory equivalent for carbon dioxide (p = 0.002), and resting dead-space gas volume to tidal volume ratio (p < 0.001). However, the independent factors for ΔPETO2 were history of diabetes (p = 0.047), estimated glomerular filtration rate (p = 0.001), and resting systolic blood pressure (p = 0.017). These findings suggested that AT PETO2 was associated with central determinants; whereas, and ΔPETO2 was associated with peripheral determinants, The AT PETO2 and ΔPETO2 provide variable insight regarding the cause of exercise intolerance and can be used to determine appropriate therapies.

Impact of worsening renal function on peak oxygen uptake in patients with acute myocardial infarction.

AIM: Worsening renal function (WRF) induced by acute myocardial infarction (AMI) is a strong predictor of cardiovascular events and mortality. Peak oxygen uptake may contribute to prognosis in AMI patients with WRF, however, the impact of WRF on peak oxygen uptake is unclear. METHODS: Among 154 patients with AMI who underwent emergency percutaneous coronary intervention and participated in phase II cardiac rehabilitation, those who underwent cardiopulmonary exercise testing were consecutively enrolled. WRF was defined as a ≥20% decrease in estimated glomerular filtration rate (eGFR [ml/min/1.73 m2 ]) from admission to that at cardiopulmonary exercise testing. The association of WRF with peak oxygen uptake was evaluated by multivariate regression analysis. The non-WRF group was divided into two subgroups according to eGFR <60/≥60 at cardiopulmonary exercise testing, and eGFR at cardiopulmonary exercise testing and peak oxygen uptake of all three groups were compared. RESULTS: Ninety-four patients were enrolled in the final analysis. Multiple linear regression analysis showed that WRF was associated with peak oxygen uptake (p = .003). Comparing the non-WRF group with eGFR at cardiopulmonary exercise testing <60 and the WRF group, although eGFR at cardiopulmonary exercise testing was similar (p = 1.000), peak oxygen uptake in the WRF group was significantly lower (p = .026). CONCLUSION: WRF, not eGFR at cardiopulmonary exercise testing was significantly associated with peak oxygen uptake in patients with AMI. This result suggests that when considering the relationship between renal function and peak oxygen uptake, WRF must be taken into account.

Impact of the COVID-19 pandemic on phase 2 cardiac rehabilitation patients in Japan.

This study aimed to clarify the effects of the interruption of cardiac rehabilitation (CR) and refraining from going outside due to the COVID-19 pandemic on hemodynamic response and rating of perceived exertion (RPE) during exercise including differences by age in phase 2 CR outpatients. Among 76 outpatients participating in consecutive phase 2 CR in both periods from March to April and June to July 2020, which were before and after CR interruption, respectively, at Sanda City Hospital were enrolled. The inclusion criterion was outpatients whose CR was interrupted due to COVID-19. We compared the data of hemodynamic response and RPE during exercise on the last day before interruption and the first day after interruption when aerobic exercise was performed at the same exercise intensity in the < 75 years group and ≥ 75 years group. Fifty-three patients were enrolled in the final analysis. Post-CR interruption, peak heart rate increased significantly (p = 0.009) in the < 75 years group, whereas in the ≥ 75 years group, weight and body mass index decreased significantly (p = 0.009, 0.011, respectively) and Borg scale scores for both dyspnea and lower extremities fatigue worsened significantly (both, p < 0.001). CR interruption and refraining from going outside due to the COVID-19 pandemic affected the hemodynamic response, RPE during exercise and body weight in phase 2 CR outpatients. In particular, patients aged ≥ 75 years appeared to be placed at an increased risk of frailty.

Increased Heart Rate during Walk Test Predicts Chronic-Phase Worsening of Renal Function in Patients with Acute Myocardial Infarction and Normal Kidney Function.

Chronic-phase worsening renal function (WRF) in patients with acute myocardial infarction (AMI) has been associated with poor prognosis. However, there is no consensus on either the method of prevention or the cause. The aim of this study was to determine factors predictive of chronic-phase WRF from the viewpoint of circulatory dynamics response to exercise during hospitalization of AMI patients without renal dysfunction on admission. We studied 186 consecutively AMI patients who underwent the 200-m walk test. Chronic-phase WRF was defined as a 20% decrease in estimated glomerular filtration rate (eGFR) from baseline to 8-10 months after AMI onset. Heart rate (HR) and systolic blood pressure recorded during the 200-m walk test were evaluated as circulatory dynamics responses. In total, 94 patients were enrolled. Multiple linear regression analysis showed that ΔHR (peak-rest) associated significantly with ΔeGFR (ß = 0.427, p = 0.018). The receiver operating characteristic curve of ΔHR to predict chronic-phase WRF showed an area under the curve of 0.77, with a cut-off value of 22.0 bpm having a 95% sensitivity and 55% specificity. Among circulatory dynamics responses during exercise in the acute phase after AMI, ΔHR was an independent predictor of chronic-phase WRF.

Review of the Japanese records of an endangered grouper, Epinephelus tukula, with comments on its population status (Teleostei, Serranidae).

The Potato Grouper, Epinephelus tukula, is relatively rare worldwide. Records from the northernmost part of its range (Japan) have been few, resulting in a "Critically Endangered" listing on the Red List for Japan. The Japanese records were revised by examining literature, new specimens, photographs, and the internet, and a continuous distribution pattern from the tropical Ryukyu Islands (including adult individuals) to temperate regions affected by the Kuroshio Current were delineated; this suggests the species inhabits tropical Japan and can spread to temperate regions via the warm current. The species possibly reproduces in Japanese waters but further reproductive ecology research is required.

Three-dimensional reconstruction of the axon extending from the dermal photoreceptor cell in the extraocular photoreception system of a marine gastropod, onchidium.

The marine gastropod Onchidium has a multiple photoreceptive system consisting of stalk eyes, dorsal eyes, photosensitive neurons, and extraocular dermal photoreceptor cells (DPCs). The DPCs were widespread all over the dorsal mantle and distributed singly or in groups in the dermis, but were not discernible by the naked eye. The DPC was oval in shape and large in size, and characterized by features specific to gastropod photoreceptor cells such as massive microvilli, photic vesicles, and a depolarized response. DPC-17, one of a group of 19 DPCs, was examined on serial semi-thin sections of 0.4 µm in thickness with a high-voltage transmission electron microscope (HVTEM). The axon emerged specifically from the lateral side between the distal microvillous portion and proximal cytoplasm, travelled through the connective tissue, and joined a small nerve bundle (NB). Two types of supportive cells were found along the length of the axon. The first type was a covering cell (CC) surrounding the surface of the DPC body and continuing onward to the axon sheath. DPC-17 was covered by 11 CCs, while the larger DPC-6 was only covered by four CCs. The second type was a sheath cell (ShC) wrapping the surface of the small NB where the axon of the DPC merged with undefined nerve fibers. The axon extending directly from DPC-17 was reconstructed three-dimensionally (3D) using DeltaViewer software. The 3D-reconstructed image of the sheath of the axon and the CC demonstrated the continuity between the two structures, especially when the image was rotated using DeltaViewer.

Computerized three-dimensional analysis of the heart and great vessels in normal and holoprosencephalic human embryos.

The developing heart and great vessels undergo drastic morphogenetic changes during the embryonic period. To analyze the normal and abnormal development of these organs, it is essential to visualize their structures in three and four dimensions, including the changes occurring with time. We have reconstructed the luminal structure of the hearts and great vessels of staged human embryos from serial histological sections to demonstrate their sequential morphological changes in three dimensions. The detailed structures of the embryonic heart and major arteries in normal and holoprosencephalic (HPE) human embryos could be reconstructed and visualized, and anatomical structures were analyzed using 3D images. By 3D analysis, cardiac anomalies such as double-outlet right ventricle and malrotation of the heart tube were identified in HPE embryos, which were not easily diagnosed by histological observation. Reconstruction and analysis of 3D images are useful for the study of anatomical structures of developing embryos and for identifying their abnormalities.