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1.
Entropy (Basel) ; 26(2)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38392374

RESUMEN

The paper provides a precise error estimate for an asymptotic expansion of a certain stochastic control problem related to relative entropy minimization. In particular, it is shown that the expansion error depends on the regularity of functionals on path space. An efficient numerical scheme based on a weak approximation with Monte Carlo simulation is employed to implement the asymptotic expansion in multidimensional settings. Throughout numerical experiments, it is confirmed that the approximation error of the proposed scheme is consistent with the theoretical rate of convergence.

2.
J Plant Res ; 137(2): 203-213, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281225

RESUMEN

A newly found leaf arrangement to reduce self-shading was observed in a Japanese warm-temperate forest. For monoaxial trees that deploy leaves directly on a single stem, leaf arrangements involving progressive elongation of the petiole and progressive increase in deflection angle (the angle between stem and petiole) from the uppermost to the lowermost leaves act to reduce self-shading. However, the progressive reduction in petiole length and deflection angle from the uppermost to the lowermost leaves should also result in the reduction of self-shading. Nevertheless, the latter leaf arrangement has not been reported previously for any tree species. Four Araliaceae species, namely, Gamblea innovans, Chengiopanax sciadophylloides, Dendropanax trifidus and Fatsia japonica, which are typical monoaxial tree species in Japan, were studied. We examined the crown structure of saplings growing in the light-limited understorey in a Japanese warm-temperate forest. Two evergreen species, Dendropanax trifidus and F. japonica showed progressive petiole elongation and progressive increase in the deflection angle from the uppermost to the lowermost leaves. In contrast, saplings of deciduous species, G. innovans and C. sciadophylloides had a leaf arrangement involving progressive reduction in petiole length and deflection angle from the uppermost to the lowermost leaves. The leaf arrangement has diversified among members of the same family, but all four studied species develop a crown with little self-shading that is adapted for growth in the light-limited understorey. Although trees are likely to be under the same selective pressure to reduce self-shading, this study revealed that there is flexibility in its morphological realisation, which has been poorly appreciated previously.


Asunto(s)
Fotosíntesis , Árboles , Árboles/anatomía & histología , Japón , Bosques , Hojas de la Planta/anatomía & histología
3.
J Plant Res ; 137(1): 79-94, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37812342

RESUMEN

In the Malvaceae family, dynamic solar tracking by leaves is actuated by the deformation of the pulvinus, a thickened region at the leaf blade-petiole junction. While the internal structure is believed to play a crucial role in this process, experimental verification has been challenging due to technical limitations. To address this gap, we developed a semi-automated workflow, which integrates data analysis and image processing to simultaneously analyze the shape and internal structure of a Malvaceae pulvinus using X-ray microtomography. Firstly, we found that kenaf (Hibiscus cannabinus L.), a Malvaceae species with curved pulvini, exhibited solar-tracking leaf movement and selected it as a model system. We employed diffusible iodine-based contrast-enhanced computed tomography to visualize the internal structure of the kenaf pulvinus. Analysis of the pulvini's shape revealed variations in pulvinus morphology, yet plausible prediction of the centerline was accomplished using polar polynomial regression. Upon slicing the pulvini perpendicular to the centerline, we observed distinct gray value gradients along the proximo-distal and adaxial-abaxial axes, challenging threshold-based tissue segmentation. This workflow successfully generated three modified 3D images and derived quantitative parameters. Using these quantitative parameters, we conducted network analysis and found the linkage between the size-normalized cortex cross-sectional area and curvature. Polynomial least absolute shrinkage and selection operator (LASSO) regression revealed the relationship between the size-normalized cortex cross-sectional area and curvature commonly in all three tested samples. This workflow enables simultaneous analysis of the shape and internal structure, significantly improving the reproducibility of Malvaceae leaf pulvinus characterization.


Asunto(s)
Hibiscus , Pulvino , Microtomografía por Rayos X , Reproducibilidad de los Resultados , Hojas de la Planta
4.
PLoS One ; 18(6): e0287114, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37307263

RESUMEN

Phyllostachys nigra var. henonis, a monocarpic bamboo with a 120-year flowering interval, is next predicted to flower in Japan in the 2020s. Because a huge area of the country is presently covered by stands of this species, post-flowering dieback of these stands and ensuing drastic changes in land cover may cause serious social and/or environmental problems. No study on the regeneration of this bamboo species was conducted during the last flowering event in the 1900s, and the regeneration process of this species is thus still unknown. In 2020, we encountered a localized flowering of P. nigra var. henonis in Japan and used this discovery as a rare opportunity to study the initial regeneration process of the species. Over 3 years, more than 80% of culms in the study site bloomed, but no seed was produced. In addition, no established seedlings were located. These facts strongly suggest that P. nigra var. henonis lacks the ability to produce seeds and cannot undergo sexual regeneration. Some bamboo culms were produced after flowering but died within 1 year of emergence. Small, weak culms (dwarf ramets) also appeared after flowering, but most died within 1 year as well. Three years after flowering, all culms had died, with no sign of regeneration detected. According to our 3 years of observation, this bamboo appears to be hard to regenerate-an idea completely contradicted by the fact that this species has long persisted in Japan. We thus considered other possible regeneration modes for P. nigra var. henonis.


Asunto(s)
Reproducción , Japón , Muerte , Poaceae , Regeneración
5.
Sci Rep ; 13(1): 10172, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349406

RESUMEN

Byttneriophyllum tiliifolium is a leaf fossil-species of the family Malvaceae that was distributed widely throughout Eurasia from the Miocene to the Pliocene. An affinity to some Malvadendrina subfamilies has been suggested for Byttneriophyllum-bearing plants, but remains to be clarified due to insufficient information on other organs. Here, we report an exceptional lower Miocene fossil locality in Japan where a monodominant forest of the wood fossil-species Wataria parvipora flourished. Notably, the forest floor was covered by a bed consisting almost exclusively of B. tiliifolium. We observed occurrence modes of B. tiliifolium in this bed that confirmed that these leaves were deposited parautochthonously. These observations imply a biological connection between B. tiliifolium and W. parvipora. The wood and leaf characters together might narrow the affinity of Byttneriophyllum-bearing plants down to Helicterioideae within the Malvadendrina, although it is also possible that Byttneriophyllum-bearing plants constitutes an extinct lineage which is characterized by a combination of morphological traits found in several extant lineages. Our results suggest that Byttneriophyllum-bearing plants started to inhabit swamps no later than the end of the early Miocene when the global temperature was getting warmer.


Asunto(s)
Biodiversidad , Fósiles , Japón , Temperatura , Bosques , Filogenia
6.
Am J Physiol Heart Circ Physiol ; 323(2): H276-H284, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35714176

RESUMEN

ß-Blocker (BB) use is a mainstay for the treatment of heart failure (HF) with reduced ejection fraction (HFrEF), whereas its efficacy for heart failure with preserved ejection fraction (HFpEF) remains controversial. Women outnumber men in HFpEF, whereas men outnumber women in HFrEF. Plasma B-type natriuretic peptide (BNP) is established as a biomarker for HF. We examined whether BB use is associated with plasma BNP levels differently in men and women with HFpEF. The study subjects comprised 721 patients with HFpEF [left ventricular ejection fraction (LVEF) ≥ 50%] (184 men, mean age 78.2 ± 9.2 yr and 537 women, mean age 83.1 ± 8.8 yr), 179 on BB (66 men and 113 women) and 542 no BB (118 men and 424 women), 583 in sinus rhythm (SR) and 138 in atrial fibrillation (AF). A multivariable logistic regression test was used. Plasma BNP levels were higher (P = 0.0005), systolic blood pressure and LVEF lower (P = 0.0003, and P = 0.0059, respectively) on BBs than on no BBs in women, whereas in men, plasma BNP levels, systolic blood pressure, and LVEF were not altered significantly (P = 0.0849, P = 0.9129, and P = 0.4718, respectively) on BBs compared with no BBs in patients with SR. Multivariable logistic regression analysis revealed that BB use and women were a positive and a negative predictor for high BNP levels (P = 0.003 and P = 0.032, respectively) in SR but not in AF. BB use was associated with high-plasma BNP levels and lower LVEF in women but not in men with HFpEF and SR, suggesting that the pathogenesis and treatment of HFpEF may differ in men and women in SR.NEW & NOTEWORTHY Pathogenesis and treatment for heart failure with preserved ejection fraction (HFpEF) may differ in men and women in sinus rhythm (SR).


Asunto(s)
Fibrilación Atrial , Insuficiencia Cardíaca , Antagonistas Adrenérgicos beta/uso terapéutico , Anciano , Anciano de 80 o más Años , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Masculino , Péptido Natriurético Encefálico , Pronóstico , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología
7.
J Cardiol ; 80(1): 56-63, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35282945

RESUMEN

BACKGROUND: This study was performed to investigate whether right ventricular global longitudinal strain (RV-GLS) provides prognostic information in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). METHODS AND RESULTS: Among 129 patients who were diagnosed with ATTRwt-CM at Kumamoto University Hospital from December 2002 to December 2019, 111 patients who had enough information for two-dimensional speckle tracking imaging were retrospectively analyzed. During a median follow-up of 615 days, 26 cardiovascular deaths occurred. Compared with patients in the non-event group, those in the cardiovascular death group were significantly older (81.1 ±â€¯7.4 years vs. 78.2 ±â€¯6.2 years, p = 0.009) and had significantly higher interventricular septal thickness in diastole (16.6 ±â€¯3.1 mm vs. 15.3 ±â€¯2.4 mm, p = 0.048), lower RV-GLS (10.9 ±â€¯2.7% vs. 12.8 ±â€¯3.5%, p = 0.010), and lower right ventricular free wall longitudinal strain (RVFWLS) (13.1 ±â€¯3.3% vs. 15.5 ±â€¯3.8%, p = 0.004). In the univariate Cox proportional hazard analysis, age, left atrial volume index (LAVI), RV-GLS, and RVFWLS were significantly associated with cardiovascular death [age, hazard ratio (HR), 1.10; 95% confidence interval (CI), 1.02-1.19, p = 0.010; LAVI, HR, 1.02; 95% CI, 1.00-1.03, p = 0.009; RV-GLS, HR, 0.86; 95% CI, 0.75-0.97, p = 0.017; RVFWLS, HR 0.89; 95% CI, 0.79-1.00; p = 0.041]. Multivariable Cox proportional hazard analysis showed RV-GLS was significantly and independently associated with cardiovascular death in patients with ATTRwt-CM (HR, 0.86; 95% CI, 0.74-0.99; p = 0.038). Receiver operating characteristic analysis showed that the area under the curve of RV-GLS for cardiovascular death was 0.668 and that the best cut-off value of RV-GLS was 11.59% (sensitivity, 69.2%; specificity, 63.5%). In the Kaplan-Meier analysis, patients with ATTRwt-CM who had low RV-GLS (<11.59%) had a significantly higher probability of total cardiovascular death (p = 0.004) and heart failure-related hospitalization (p = 0.013). CONCLUSION: RV-GLS has significant prognostic value in patients with ATTRwt-CM and provides greater prognostic power than conventional echocardiographic findings.


Asunto(s)
Amiloidosis , Cardiomiopatías , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Humanos , Prealbúmina/genética , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos
8.
ESC Heart Fail ; 9(3): 1731-1739, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35191205

RESUMEN

AIMS: It has been reported that a staging system combining N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T (hs-cTnT) or estimated glomerular filtration rate (eGFR) is useful in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). However, these studies were mainly conducted in Western countries, and their usefulness for the Japanese population is unclear. We examined and validated the staging system using hs-cTnT, eGFR, and B-type natriuretic peptide (BNP) in Japanese patients with ATTRwt-CM. METHODS AND RESULTS: We retrospectively evaluated 176 patients with ATTRwt-CM. The cut-off values of hs-cTnT and eGFR were selected as 0.05 ng/mL and 45 mL/min/1.73 m2 , respectively, based on a previous report. The optimal cut-off value of BNP was 255.6 pg/mL to predict all-cause mortality (sensitivity, 75%; specificity, 58%; area under the curve, 0.69; 95% confidence interval [CI], 0.61-0.78; P < 0.001) based on a receiver operating characteristic curve. We defined the cut-off value of BNP as 250 pg/mL. Increased hs-cTnT (>0.05 ng/mL) and BNP (>250 pg/mL) and decreased eGFR (<45 mL/min/1.73 m2 ) were significant predictors of poor prognosis (P < 0.05). We calculated the score by adding 1 point if hs-cTnT and BNP levels increased or eGFR decreased by more than the cut-off value. The hazard ratio of all-cause death adjusted by age and sex, using score 0 as a reference, was 0.44 (95% CI 0.08-2.49, P = 0.44) for score 1, 3.69 (95% CI 1.21-11.21, P = 0.02) for score 2, and 5.40 (95% CI 1.57-18.54, P = 0.007) for score 3. We divided patients into a low score group (0-1 point) and high score group (2-3 points). Kaplan-Meier analyses revealed significant differences in all-cause death and rehospitalization for heart failure (log rank test; P < 0.001), and after adjusting for sex and age, the hazard ratio of all-cause death was 6.96 (95% Cl 2.88-16.83, P < 0.001) and that for rehospitalization for heart failure was 4.27 (95% Cl 2.26-8.07, P < 0.001) in the high-risk group, compared with those in the low-risk group. The median survival period was 32.0 months in the high-risk group. CONCLUSIONS: This simple staging system, which combines hs-cTnT, BNP, and eGFR, was useful for predicting prognosis in Japanese patients with ATTRwt-CM. This system can objectively evaluate the disease progression of ATTRwt-CM and may be useful for patient selection for disease-modifying therapy.


Asunto(s)
Amiloidosis , Cardiomiopatías , Insuficiencia Cardíaca , Biomarcadores , Cardiomiopatías/diagnóstico , Insuficiencia Cardíaca/diagnóstico , Humanos , Japón/epidemiología , Péptido Natriurético Encefálico , Prealbúmina , Estudios Retrospectivos
9.
J Cardiol ; 79(1): 50-57, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34756766

RESUMEN

BACKGROUND: A significant male predominance has been reported in wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). Hence, female cases of ATTRwt-CM are overlooked, and sex-related differences in ATTRwt-CM remain unclear. This study aimed to examine sex-related differences in clinical characteristics and diagnostic approaches in ATTRwt-CM. METHODS: We retrospectively analyzed 199 consecutive patients who were diagnosed with ATTRwt-CM and evaluated sex-related differences in clinical characteristics, imaging parameters, biomarkers, and diagnostic approaches. RESULTS: Twenty-nine patients (15%) were female. These female patients were significantly older at diagnosis (77.1 ± 6.5 years vs. 82.9 ± 4.8 years; p<0.001) and had a more advanced New York Health Association functional class (2.2 ± 0.7 vs. 2.6 ± 0.8; p = 0.006) than their male counterparts. The median B-type natriuretic peptide levels were significantly higher (236 pg/mL vs. 394 pg/mL; p = 0.017) in female patients. Echocardiography revealed that the mean interventricular septum diameter was thinner (15.7 ± 2.6 mm vs. 14.1 ± 2.5 mm; p = 0.004) and left ventricular ejection fraction (LVEF) was preserved (51.2 ± 10.2% vs. 57.2 ± 9.1%; p = 0.003) in female patients. The mean heart-to-contralateral ratio obtained using 99mTc-labeled pyrophosphate (99mTc-PYP) was significantly lower (1.89 ± 0.33 vs. 1.63 ± 0.20; p < 0.001), moderate to severe aortic stenosis was more frequently observed (5% vs. 45%; p < 0.001), and the frequency of histological diagnosis was significantly lower (77% vs. 59%; p = 0.036) in female patients. CONCLUSIONS: Female patients with ATTRwt-CM were predominantly octogenarians and less hypertrophic and had preserved LVEF and weaker cardiac uptake of the 99mTc-PYP tracer compared with male patients. These characteristics contribute to the underdiagnosis of ATTRwt-CM in female patients.


Asunto(s)
Neuropatías Amiloides Familiares , Cardiomiopatías , Anciano de 80 o más Años , Neuropatías Amiloides Familiares/diagnóstico por imagen , Neuropatías Amiloides Familiares/patología , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Femenino , Humanos , Masculino , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda
10.
Biol Lett ; 17(12): 20210403, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34847752

RESUMEN

The fossil record of terrestrialization documents notable shifts in the environmental and physiological tolerances of many animal and plant groups. However, for certain significant components of modern freshwater and terrestrial environments, the transition out of marine settings remains largely unconstrained. Ostracod crustaceans occupy an exceptional range of modern aquatic environments and are invaluable palaeoenvironmental indicators in the fossil record. However, pre-Carboniferous records of supposed non-marine and marginal marine ostracods are sparse, and the timing of their marine to non-marine transition has proven elusive. Here, we reassess the early environmental history of ostracods in light of new assemblages from the late Silurian of Vietnam. Two, low diversity but distinct ostracod assemblages are associated with estuarine deposits. This occurrence is consistent with previous incidental reports of ostracods occupying marginal and brackish settings through the late Silurian and Devonian. Therefore, ostracods were pioneering the occupation of marginal marine and estuarine settings 60 Myr before the Carboniferous and they were a component of the early phase of transition from marine to non-marine environments.


Asunto(s)
Crustáceos , Estuarios , Animales , Fósiles , Agua Dulce , Plantas
11.
ESC Heart Fail ; 8(6): 5316-5326, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34582129

RESUMEN

AIMS: This study was performed to investigate whether left atrial (LA) strain by echocardiography provides prognostic information in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). METHODS AND RESULTS: Among 129 patients who were diagnosed with ATTRwt-CM at Kumamoto University Hospital from December 2002 to December 2019, 113 patients who had enough information for two-dimensional speckle tracking echocardiography were enrolled in this study. During a median follow-up of 668 days, 28 cardiovascular deaths occurred. Compared with patients in the non-event group, those in the cardiovascular death group were significantly older (81.5 ± 7.4 vs. 78.1 ± 6.1 years, P < 0.01), had a lower incidence of carpal tunnel syndrome (21% vs. 47%, P < 0.05), and had a higher high-sensitivity cardiac troponin T [0.085 (0.063-0.105) vs. 0.049 (0.036-0.079) ng/mL, P < 0.01] and B-type natriuretic peptide concentrations [419 (239-541) vs. 271 (155-462) pg/mL, P < 0.01] and lower estimated glomerular filtration rate (41.8 ± 15.4 vs. 53.4 ± 14.6 mL/min/1.73 m2 , P < 0.01). Electrocardiography showed higher rate of a V1-V3 QS pattern (52% vs. 24%, P < 0.01) and complete left bundle branch block (27% vs. 6%, P < 0.01), and echocardiography showed a significantly lower peak LA strain rate during the contraction phase (0.16 ± 0.13 vs. 0.28 ± 0.27 S-1 , P < 0.05), LA strain during the reservoir phase (LASr) (5.84 ± 2.41 vs. 8.22 ± 4.05%, P < 0.01), and peak LA strain rate during the reservoir phase (0.26 ± 0.09 vs. 0.33 ± 0.15 S-1 , P < 0.05) in the cardiovascular death group than in non-event group. By contrast, conventional echocardiographic findings were not significantly different between these two groups. After adjusting for conventional predictive factors of ATTRwt-CM (age, high-sensitivity cardiac troponin T and B-type natriuretic peptide concentrations, and estimated glomerular filtration rate), multivariable Cox proportional hazard analyses showed that LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt-CM (odds ratio, 0.84; 95% confidence interval, 0.72-0.98; P < 0.05). After adjusting for age and echocardiographic findings associated with cardiovascular death (LA volume index and peak LA strain rate during the contraction phase), LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt-CM (odds ratio, 0.83; 95% confidence interval, 0.70-0.98; P < 0.05). Receiver operating characteristic curve analysis showed that the area under the curve of LASr for cardiovascular death was 0.686 and that the best cut-off value of LASr was 6.69% (sensitivity, 62.4%; specificity, 64.3%). In the Kaplan-Meier analysis, patients with low LASr (<6.69%) had a significantly higher probability of total cardiovascular death (P < 0.05) and heart failure-related hospitalization (P < 0.05). CONCLUSIONS: Left atrial strain during the reservoir phase provides significant prognostic value in patients with ATTRwt-CM even after adjusting for conventional predictive factors.


Asunto(s)
Cardiomiopatías , Prealbúmina , Cardiomiopatías/diagnóstico , Ecocardiografía/métodos , Atrios Cardíacos/diagnóstico por imagen , Humanos , Pronóstico
12.
J Am Heart Assoc ; 10(15): e021069, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34320813

RESUMEN

Background Cardiac fibrosis plays a crucial role in the pathogenesis of dilated cardiomyopathy (DCM). HE4 (human epididymis protein 4) is a secretory protein expressed in activated fibroblasts that exacerbates tissue fibrosis. In the present study, we investigated the clinical utility of HE4 measurement in patients with DCM and its pathophysiological role in preclinical experiments in vivo and in vitro. Methods and Results We measured serum HE4 levels of 87 patients with DCM. Endomyocardial biopsy expressed severe fibrosis only in the high HE4 group (P<0.0001). Echocardiography showed that left ventricular end-diastolic diameter tends to decrease over time (58±7.3 to 51±6.6 mm; P<0.0001) in the low HE4 group (<59.65 pmol/L [median value]). HE4 was significantly associated with risk reduction of mortality and cardiovascular hospitalization in multivariate Cox model. In vivo, HE4 was highly expressed in kidney and lung tissue of mouse, and scarcely expressed in heart. In genetically induced DCM mouse model, HE4 expression increased in kidney but not in heart and lung. In vitro, supernatant from HE4-transfected human embryonic kidney 293T cells enhanced transdifferentiation of rat neonatal fibroblasts and increased expression of fibrosis-related genes, and this was accompanied by the activation of extracellular signal-regulated kinase signaling in cardiac fibroblasts. Treatment with an inhibitor of upstream signal of extracellular signal-regulated kinase or a neutralizing HE4 antibody canceled the profibrotic properties of HE4. Conclusions HE4 functions as a secretory factor, activating cardiac fibroblasts, thereby inducing cardiac interstitial fibrosis. HE4 could be a promising biomarker for assessing ongoing fibrosis and a novel therapeutic target in DCM. Registration URL: https://upload.umin.ac.jp/cgi-open-bin/ctr; Unique identifier: UMIN000043062.


Asunto(s)
Cardiomiopatía Dilatada , Fibrosis Endomiocárdica , Ventrículos Cardíacos , Riñón , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAP , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Biopsia/métodos , Síndrome Cardiorrenal/metabolismo , Síndrome Cardiorrenal/patología , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/mortalidad , Cardiomiopatía Dilatada/patología , Cardiomiopatía Dilatada/terapia , Transdiferenciación Celular , Descubrimiento de Drogas , Fibrosis Endomiocárdica/metabolismo , Fibrosis Endomiocárdica/patología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Hospitalización/estadística & datos numéricos , Humanos , Riñón/metabolismo , Riñón/patología , Ratones , Miocardio/metabolismo , Miocardio/patología , Miofibroblastos/fisiología , Valor Predictivo de las Pruebas , Ratas , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAP/antagonistas & inhibidores , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAP/inmunología , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAP/metabolismo
13.
Nat Metab ; 3(2): 196-210, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33619377

RESUMEN

Ketone bodies are generated in the liver and allow for the maintenance of systemic caloric and energy homeostasis during fasting and caloric restriction. It has previously been demonstrated that neonatal ketogenesis is activated independently of starvation. However, the role of ketogenesis during the perinatal period remains unclear. Here, we show that neonatal ketogenesis plays a protective role in mitochondrial function. We generated a mouse model of insufficient ketogenesis by disrupting the rate-limiting hydroxymethylglutaryl-CoA synthase 2 enzyme gene (Hmgcs2). Hmgcs2 knockout (KO) neonates develop microvesicular steatosis within a few days of birth. Electron microscopic analysis and metabolite profiling indicate a restricted energy production capacity and accumulation of acetyl-CoA in Hmgcs2 KO mice. Furthermore, acetylome analysis of Hmgcs2 KO cells revealed enhanced acetylation of mitochondrial proteins. These findings suggest that neonatal ketogenesis protects the energy-producing capacity of mitochondria by preventing the hyperacetylation of mitochondrial proteins.


Asunto(s)
Metabolismo Energético/fisiología , Cuerpos Cetónicos/biosíntesis , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Acetilación , Animales , Animales Recién Nacidos , Hidroximetilglutaril-CoA Sintasa/genética , Hidroximetilglutaril-CoA Sintasa/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Microvasos/fisiología , Consumo de Oxígeno
14.
New Phytol ; 229(1): 460-468, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32696978

RESUMEN

Roots have played a pivotal role in the conquest of land by vascular plants, yet their origin has remained enigmatic. Palaeobotanical evidence suggests that roots may have originated from subterranean shoots in some lycophyte species. If this hypothesis is correct, it would follow that the roots and shoots of extant lycophytes share fundamental developmental mechanisms. We tracked meristem dynamics in root and shoot apices of Lycopodium clavatum using a thymidine analogue and expression patterns of histone H4, respectively. Then we compared the meristem dynamics of roots and shoots to identify developmental similarities. Both apical meristems contained a quiescent tissue characterised by a low frequency of cell division. Actively dividing cells appeared in the quiescent tissue during dichotomous branching of both roots and shoots. As a result, the parental meristem divides into two daughter meristems, which give rise to new root or shoot apices. These striking similarities in meristem dynamics provide new neobotanical data that support the shoot-origin hypothesis of lycophyte roots. Although Lycopodium roots may have originated from subterranean shoots of Devonian lycophytes, these shoots may have changed into root-bearing axes in other extant lycophyte lineages.


Asunto(s)
Lycopodium , Meristema , División Celular , Raíces de Plantas , Brotes de la Planta
16.
J Cardiol Cases ; 22(3): 140-142, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32884598

RESUMEN

Mycoplasma infection and pregnancy are both characterized by thrombogenesis. A 38-year-old pregnant woman was admitted to a general hospital for mycoplasma pneumonia treatment. She experienced sudden dyspnea and fell into cardiopulmonary arrest. Emergent pulmonary arteriography revealed contrast deficits in the bilateral pulmonary arteries, and she was diagnosed with pulmonary thromboembolism (PTE). Reperfusion treatment and hemodynamic support were initiated. This is a rare case report of PTE attributed to mycoplasma infection during pregnancy. .

17.
ESC Heart Fail ; 7(5): 2829-2837, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32672425

RESUMEN

AIMS: The focus on wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is increasing because of novel treatment options. There is currently no report on a large number of Japanese patients with ATTRwt-CM. The study aimed to examine the characteristics and prognosis of ATTRwt-CM in Japan. METHODS AND RESULTS: Consecutive patients (78.5 ± 6.4 years old at diagnosis) with ATTRwt-CM diagnosed at Kumamoto University Hospital between December 2002 and December 2019 were retrospectively reviewed. Data, including demographic characteristics, co-morbidities, clinical manifestations at diagnosis, laboratory results, electrocardiographic and echocardiographic data, imaging and pathological findings, and treatment were obtained. Of 129 patients included in this study, 110 patients (85%) were male. The median period from initial symptom onset to diagnosis was 15.5 (2-75) months. Heart failure was the most common clinical manifestation leading to diagnosis (61%) and initial manifestations (49%). Of 106 patients, carpal tunnel syndrome was observed in 57 patients (54%), and the median period from initial symptom onset to diagnosis was 96 (48-120) months. Histopathological confirmation of transthyretin amyloid was achieved in 94 patients (73%), including 66 (51%) and 28 cases (22%) with endomyocardial and extracardiac biopsies. During the observation period (median 15.0 [inter-quartile range, 5.4-33.2] months after diagnosis), 34 patients (26%) died. Of these, 27 patients (79%) had cardiovascular deaths (heart failure, 25; sudden death, two). The median survival duration was 58.9 months and the 5 years' survival rate was 48%. According to a multivariate Cox hazard analysis, age [hazard ratio (HR), 1.14; 95% confidence interval (CI), 1.05-1.23, P = 0.002] and low serum sodium levels (HR, 0.89; 95% CI, 0.79-0.996; P = 0.04) contributed to all-cause mortality, and low serum sodium levels contributed to hospitalization for heart failure (HR, 0.86; 95% CI, 0.77-0.96; P = 0.005). CONCLUSIONS: Clinical characteristics and prognosis of ATTRwt-CM patients in Japan were examined. Carpal tunnel syndrome can be considered an indication for diagnosis of ATTRwt-CM. Age and low serum sodium level were significant predictive factors of all survival outcomes. The clinical features of ATTRwt-CM should be recognized to provide appropriate treatment.


Asunto(s)
Neuropatías Amiloides Familiares , Cardiomiopatías , Anciano , Anciano de 80 o más Años , Neuropatías Amiloides Familiares/diagnóstico , Neuropatías Amiloides Familiares/epidemiología , Cardiomiopatías/diagnóstico , Cardiomiopatías/epidemiología , Femenino , Humanos , Japón/epidemiología , Masculino , Prealbúmina , Estudios Retrospectivos
18.
J Plant Res ; 133(3): 291-296, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32002717

RESUMEN

The independent origin of roots in lycophytes and euphyllophytes has been proposed, mainly based on paleobotanical records. However, the question of how roots evolved within these lineages remains unresolved. Root apical meristem (RAM) organization in lycophytes would provide a clue toward understanding the early evolution of roots. Recently, we examined RAM organization in lycophytes (Lycopodiaceae, Isoetaceae, and Selaginellaceae) in terms of cell division activity and anatomy, comparing RAM among vascular plants. Lycophyte RAM exhibited four organization types (I, II, III, and apical); thus, RAM organization in extant lycophytes was more diverse than expected. Type I RAM contained a region with very low cell division frequency, reminiscent of the quiescent center (QC) in seed plant RAM. Although some euphyllophyte RAMs were structurally similar to types II and III and apical cell-type RAM, lycophyte RAM of types II and III had no QC-like area. These results support the paleobotanical predictions that roots evolved several times in lycophytes, as well as in euphyllophytes. In this review, we also introduce recent findings on RAM organization in extant lycophytes and discuss the origin of roots in vascular plants.


Asunto(s)
Lycopodiaceae/crecimiento & desarrollo , Meristema/citología , Raíces de Plantas/citología , Evolución Biológica , División Celular , Lycopodiaceae/citología
19.
Hypertension ; 75(1): 98-108, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31735083

RESUMEN

Sirt (Sirtuin) 7, the most recently identified mammalian sirtuin, has been shown to contribute to appropriate wound healing processes after acute cardiovascular insult. However, its role in the development of cardiac remodeling after pressure overload is unclear. Cardiomyocyte-specific Sirt7-knockout and control mice were subjected to pressure overload induced by transverse aortic constriction. Cardiac hypertrophy and functions were then examined in these mice. Sirt7 protein expression was increased in myocardial tissue after pressure overload. Transverse aortic constriction-induced increases in heart weight/tibial length were significantly augmented in cardiomyocyte-specific Sirt7-knockout mice compared with those of control mice. Histological analysis showed that the cardiomyocyte cross-sectional area and fibrosis area were significantly larger in cardiomyocyte-specific Sirt7-deficient mice. Cardiac contractile functions were markedly decreased in cardiomyocyte-specific Sirt7-deficient mice. Mechanistically, we found that Sirt7 interacted directly with GATA4 and that the exacerbation of phenylephrine-induced cardiac hypertrophy by Sirt7 knockdown was decreased by GATA4 knockdown. Sirt7 deacetylated GATA4 in cardiomyocytes and regulated its transcriptional activity. Interestingly, we demonstrated that treatment with nicotinamide mononucleotide, a known key NAD+ intermediate, ameliorated agonist-induced cardiac hypertrophies in a Sirt7-dependent manner in vitro. Sirt7 deficiency in cardiomyocytes promotes cardiomyocyte hypertrophy in response to pressure overload. Sirt7 exerts its antihypertrophic effect by interacting with and promoting deacetylation of GATA4.


Asunto(s)
Cardiomegalia/metabolismo , Factor de Transcripción GATA4/metabolismo , Miocitos Cardíacos/metabolismo , Sirtuinas/metabolismo , Acetilación , Animales , Cardiomegalia/genética , Cardiomegalia/patología , Factor de Transcripción GATA4/genética , Ratones , Ratones Noqueados , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/patología , Sirtuinas/genética
20.
Disasters ; 43(1): 181-205, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29968919

RESUMEN

This paper evaluates the mitigation effect of Tokai earthquake measures on housing damage using a counterfactual approach. It focuses on those measures that stimulate ex-ante investment in disaster prevention in the supposedly affected area, including earthquake-proof retrofitting and improved housing construction; the effect of the measures on housing losses is estimated monetarily. The study compares factual disaster damage computed using a real distribution of houses with counterfactual damage to a hypothetical housing distribution that would occur if the measures were not implemented. The key findings are: (i) the disaster mitigation effects of Tokai earthquake measures on housing amount to approximately JPY 18 billion (USD 0.18 billion) for Yamanashi Prefecture and JPY 0.26 trillion (USD 2.6 billion) for Shizuoka Prefecture, which would be at the centre of the event; (ii) a before-after comparison biases estimates of the mitigation effect; and (iii) statistically, the measures do not mitigate the housing damage predicted for an earthquake in Tokai.


Asunto(s)
Desastres , Terremotos , Vivienda , Humanos , Japón , Medición de Riesgo/métodos
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