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1.
Artículo en Inglés | MEDLINE | ID: mdl-38939119

RESUMEN

A 79-year-old Japanese woman, who had undergone pancreaticoduodenectomy 6 months prior to presentation owing to pancreatic cancer, complained of jaundice with high fever. Computed tomography revealed proximal bile duct dilatation with complete hepaticojejunostomy anastomotic stricture (HJAS). We performed a single-balloon endoscopy for biliary drainage. The presence of a scar-like feature surrounding the anastomosis was identified as the HJAS. White-light imaging during single-balloon endoscopy revealed that the HJAS contained a milky whitish area (MWA), suggesting that a membranous and fibrosis layer affected continuous inflammation around the center of the anastomosis (within a scar-like feature). Endoscopic dilatation was performed using an endoscopic injection needle, with the MWA used as an indicator. A 23-gauge endoscopic injection needle was used to penetrate the center of the blind lumen within the MWA, and a pinhole was created in the stricture. After confirming the position of the proximal bile duct using a contrast medium with the needle, an endoscopic guidewire with a cannula was inserted into the pinhole. A through-the-scope sequential balloon dilator was used to dilate the stricture, and a plastic stent was inserted into the proximal bile duct. This endoscopic intervention led to positive outcomes. In cases of complete HJAS occlusion, an endoscopic approach to the bile duct is difficult because the anastomotic opening of the HJAS is not visible. Thus, puncturing within the MWA, which can be used as a scar-like landmark within a complete membranous HJAS, is considered a useful endoscopic strategy.

2.
Hypertens Res ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256527

RESUMEN

Hypertension in children and adolescents is associated with increased risk of hypertension and cardiovascular disease (CVD) in adulthood. Therefore, preventing hypertension among children and adolescents is an important public health objective worldwide. Although the importance of hypertension in children and adolescents has increasingly been recognized, the field of research is relatively new and evidence for etiologies, prevention and treatment is sparse. This review mainly summarizes the content regarding hypertension in children and adolescents published in Hypertension Research in 2023/24. Highlights include the following: The prevalence of hypertension was higher in female than male Japanese junior high school students (13.7% vs. 4.7%), but there was no significant gender difference among Japanese senior high school students (7.4% vs. 5.4%). Hematological parameters, including red blood cell counts, hemoglobin counts, hematocrit and iron levels, were positively associated with blood pressure (BP) levels in healthy children and adolescents. Higher-risk longitudinal BP trajectories in early life were associated with increased risk of target organ damage (TOD) and higher combined TOD load in midlife. BP phenotypes (e.g., masked hypertension, white-coat hypertension) assessed using office and 24-h ambulatory BP monitoring were not highly reproducible in children. The salt check sheet was a useful tool for evaluating the approximate dietary salt intake in Japanese children and adolescents. It is recommended that healthcare providers screen for hypertension in children and adolescents and recognize the importance of early intervention for those with elevated BP levels. Beginning in childhood, continuous education on hypertension and proper dietary salt intake are key to reducing the risk of hypertension and decreasing the burden of CVD in adulthood.

4.
Environ Sci Pollut Res Int ; 31(38): 50654-50669, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39103578

RESUMEN

This study extended the theory of planned behaviour (TPB) and applied it to analyse influencing factors of food waste separation intention (FSI) among households in central Vietnam. Partial least squares structural equation modelling (PLS-SEM) was employed to analyse the data. The heterogeneity of factors contributing to FSI in cities of three levels was examined using multi-group analysis (MGA). The results indicate that attitudes, subjective norms (SN), perceived behavioural control (PBC), awareness of benefit (AB), information publicity (IP), facility availability (FA), and trust significantly affected FSI of households. MGA results indicated the heterogeneity of impacts of PBC and attitude on FSI of households among three municipal levels. The results will serve as basic data for waste officers, solid-waste management project leaders, non-governmental organisations (NGOs), and other related stakeholders to lay the foundation of food waste management planning in terms of regional scale and local scale. This study will also aid the creation of a circular economy by providing a scientific base for enhancing food waste separation at source in central Vietnam.


Asunto(s)
Residuos Sólidos , Administración de Residuos , Vietnam , Administración de Residuos/métodos , Eliminación de Residuos , Intención , Humanos , Alimentos , Alimento Perdido y Desperdiciado
5.
Rev Esp Enferm Dig ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967266

RESUMEN

Iatrogenic trauma and perforation are among the most concerning complications of endoscopic retrograde cholangiopancreatography (ERCP). A 76-year-old man presented for management of obstructive jaundice caused by pancreatic cancer. The ERCP was planned for further evaluation of pancreatic cancer and endoscopic biliary drainage. The ERCP scope could not pass because of resistance during the initial attempt to insert it through the pyriform sinus. After two attempts, mild bleeding occurred in the oral cavity, and the ERCP scope was successfully inserted in the esophagus. Tissue debris was observed in the esophagus; however, it was considered attributable to damage during insertion. Because passage was difficult, we placed a guidewire deep in the duodenum to ensure an accurate route and removed the ERCP scope. Then, we switched to direct-view esophagogastroduodenoscopy (EGD) and observed the pyriform sinus. EGD showed an irregular ridge and stenosis, which were determined to comprise a pyriform sinus tumor. Tissue fragments at the ERCP insertion site were retrieved for pathological examination. The ERCP scope was inserted using a guidewire, and biliary drainage was completed. When unexpected resistance is noticed, endoscopic manipulation should be stopped, and a detailed evaluation should be conducted. Endoscopists, particularly trainees with limited procedural experience, should be vigilant of these potential complications.

8.
J Am Heart Assoc ; 12(23): e030992, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38038188

RESUMEN

BACKGROUND: Blood pressure (BP) thresholds for diagnosing and managing hypertension vary for office, home, and ambulatory readings, and between guideline documents. This analysis determined corresponding office, home, and ambulatory BP thresholds using baseline data from the HI-JAMP (Home-Activity Information and Communication Technology-Based Japan Ambulatory Blood Pressure Monitoring Prospective) study, which used a validated "all-in-one" BP monitoring device. METHODS AND RESULTS: Data from 2322 treated patients with hypertension who underwent office BP measurement, then 24-hour ambulatory BP monitoring, then home BP monitoring for 5 days were analyzed. Corresponding BP thresholds for office, home, and ambulatory measurements were determined using Deming regression. Values equivalent to office systolic BP (SBP) of 120 and 140 mm Hg were as follows: 115.9 and 127.7 mm Hg for 24-hour ambulatory SBP; 120.8 and 134.0 mm Hg for daytime ambulatory SBP; 104.9 and 117.9 mm Hg for nighttime ambulatory SBP; and 122.0 and 134.2 mm Hg for morning-evening average home SBP. Deming regression showed that morning-evening average home SBP and daytime ambulatory SBP were almost the same (home SBP=0.99×daytime ambulatory SBP+0.27 mm Hg; r=0.627). Morning-evening average home SBP values of 120 and 135 mm Hg were equivalent to daytime ambulatory SBP values of 119.1 and 133.9 mm Hg, respectively. A home SBP threshold of 130 mm Hg corresponded to 24-hour and nighttime ambulatory SBP values of 123.5 and 113.6 mm Hg, whereas a home SBP threshold of 135 mm Hg corresponded to 24-hour and nighttime ambulatory SBP values of 128.0 and 119.2 mm Hg. CONCLUSIONS: Ambulatory and home BP thresholds in this analysis were similar to those proposed by existing guidelines. The similarity between the home BP and daytime ambulatory BP thresholds was a clinically relevant finding.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión , Humanos , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial/métodos , Estudios Prospectivos , Hipertensión/diagnóstico , Determinación de la Presión Sanguínea
9.
Artículo en Inglés | MEDLINE | ID: mdl-37878534

RESUMEN

For adopting recently introduced hypertension phenotypes categorized using office and out of office blood pressure (BP) for the diagnosis of hypertension and antihypertension drug therapy, it is mandatory to define the corresponding out of office BP with the specific target BP recommended by the major guidelines. Such conditions include white-coat hypertension (WCH), masked hypertension (MH), white-coat uncontrolled hypertension (WUCH), and masked uncontrolled hypertension (MUCH). Here, the authors review the relevant literature and discuss the related issue to facilitate the use of corresponding BPs for proper diagnosis of WCH, MH, WUCH, and MUCH in the setting of standard target BP as well as intensive target BP. The methodology of deriving the corresponding BP has evolved from statistical methods such as standard deviation, percentile value, and regression to an outcome-based approach using pooled international cohort study data and comparative analysis in randomized clinical trials for target BPs such as the SPRINT and STEP studies. Corresponding BPs to 140/90 and 130/80 mm Hg in office BP is important for safe and strict achievement of intensive BP targets. The corresponding home, daytime, and 24-h BPs to 130/80 mm Hg in office BP are 130/80, 130/80, and 125/75 mm Hg, respectively. However, researchers have found some discrepancies among the home corresponding BPs. As tentative criterion for de-escalation of antihypertensive therapy as shown in European guidelines was 120 mm Hg in office BP, corresponding home, daytime, and 24-h systolic BPs to 120 mm Hg in office systolic BP are 120, 120, and 115 mm Hg, respectively.

10.
Hypertension ; 80(11): 2464-2472, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37671575

RESUMEN

BACKGROUND: Home blood pressure (BP) is an important component of digital strategies for hypertension management. However, no studies have used the same device to investigate 24-hour BP control status in relation to different home BP control thresholds. METHODS: Participants in the general practitioner-based, multicenter HI-JAMP study (Home-Activity Information and Communication Technology-Based Japan Ambulatory Blood Pressure Monitoring Prospective) underwent office BP measurement, then 24-hour ambulatory BP monitoring, then home BP monitoring for 5 days. A validated all-in-one BP monitoring device was used to measure office, home, and ambulatory BP. Baseline data were used to investigate ambulatory BP control status in individuals with well-controlled home BP based on the different guideline thresholds (125/75 mm Hg, 130/80 mm Hg, and 135/85 mm Hg). RESULTS: Data from 2269 patients were analyzed. For individuals with well-controlled home BP <135/85 mm Hg (59.5% of the total population), the prevalence of uncontrolled 24-hour (≥130/80 mm Hg), daytime (≥135/85 mm Hg), and nighttime ambulatory BP (≥120/70 mm Hg) was 19.9%, 18.5%, and 33.6%, respectively. Corresponding prevalence rates in the 42.7% of participants with well-controlled home BP <130/80 mm Hg were 13.4%, 12.9%, and 26.0%, and when well-controlled home BP was strictly defined as <125/75 mm Hg (23.9% of the population), prevalence of rates of uncontrolled 24-hour, daytime, and nighttime ambulatory BP were 7.0%, 9.0%, and 15.3%, respectively. CONCLUSIONS: Home BP control status defined using different thresholds could predict 24-hour ambulatory BP control status in treated hypertension. One-third of individuals still had uncontrolled nocturnal hypertension when home BP was controlled to <135/85 mm Hg, but ambulatory BP was quite well controlled when home BP was <125/75 mm Hg.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión , Humanos , Presión Sanguínea/fisiología , Determinación de la Presión Sanguínea , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Estudios Prospectivos
11.
Hypertens Res ; 46(12): 2561-2574, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37605071

RESUMEN

Recent innovations in digital technology have enabled the simultaneous accumulation, and the linking and analysis of time-series big data relating to several factors that influence blood pressure (BP), including biological indicators, physical activity, and environmental information. Various approaches can be used to monitor BP: in the office/clinic; at home; 24-h ambulatory recording; or with wearable and cuffless devices. Of these, home BP monitoring is a reliable and convenient method, and is recommended for hypertension management by current national and international guidelines. This recommendation is based on evidence showing that home BP is an important predictor of cardiovascular, cerebrovascular and kidney disease in patients with hypertension. In addition, lifetime personalized health record (PHR)-based home BP with telemonitoring combined with co-interventions has been shown to lower BP more effectively than the traditional approach based on office BP. Thus, home BP represents a key metric for personalized anticipation medicine, from digital healthcare to digital medicine. This paper summarizes the latest evidence on home BP monitoring and proposes a Hypertension Cardiovascular Outcome Prevention and Evidence in Asia (HOPE Asia) Network consensus on a home BP-centered approach to the management of hypertension.


Asunto(s)
Hipertensión , Humanos , Presión Sanguínea , Hipertensión/diagnóstico , Hipertensión/terapia , Determinación de la Presión Sanguínea/métodos , Monitoreo Ambulatorio de la Presión Arterial , Asia
12.
Hypertens Res ; 46(9): 2113-2123, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37076610

RESUMEN

While home blood pressure (BP) measurement is recommended for hypertension management, the clinical implications of peak home BP values have not been well studied. This study investigated the association between pathological threshold or frequency of peak home BP and cardiovascular events in patients with ≥1 cardiovascular risk factor. The Japan Morning Surge-Home Blood Pressure (J-HOP) study enrolled participants from 2005-2012 with extended follow-up from December 2017 to May 2018, which generated the dataset for this analysis. Average peak home systolic BP (SBP) was defined as average of the highest three BP values on 14-day measurement period. Patients were divided into quintiles of peak home BP, and the risk of stroke, coronary artery disease (CAD) and atherosclerotic cardiovascular disease (ASCVD; stroke+CAD) was determined. In 4231 patients (mean 65 years) followed for 6.2 years there were 94 strokes and 124 CAD events. The adjusted hazard ratio (HR) (95% CI) for the risk of stroke and ASCVD in patients with average peak home SBP in the highest versus lowest quintile was 4.39 (1.85-10.43) and 2.04 (1.24-3.36), respectively. Risk was greatest for stroke in the first 5 years: HR 22.66 (2.98-172.1). The pathological threshold of average peak home SBP for 5-year stroke risk was 176 mmHg. There was a linear association between the number of times peak home SBP > 175 mmHg and stroke risk. Peak home BP was a strong risk factor for stroke, especially within the first 5 years. We propose exaggerated peak home SBP > 175 mmHg as an early and strong novel risk factor for stroke.


Asunto(s)
Enfermedad de la Arteria Coronaria , Hipertensión , Accidente Cerebrovascular , Humanos , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial , Hipertensión/complicaciones , Enfermedad de la Arteria Coronaria/complicaciones , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología
13.
Artículo en Inglés | MEDLINE | ID: mdl-36767594

RESUMEN

Hypertension is the most frequent modifiable risk factor associated with cardiovascular disease (CVD) morbidity and mortality. Even in older people, strict blood pressure (BP) control has been recommended to reduce CVD event risks. However, caution should be exercised since older hypertensive patients have increased physical vulnerability due to frailty and multimorbidity, and older patients eligible for clinical trials may not represent the general population. Medical telemonitoring systems, which enable us to monitor a patient's medical condition remotely through digital communication, have become much more prevalent since the coronavirus pandemic. Among various physiological parameters, BP monitoring is well-suited to the use of such systems, which enable healthcare providers to deliver accurate and safe BP management, even in the presence of frailty and/or living in geographically remote areas. Furthermore, medical telemonitoring systems could help reduce nonadherence to antihypertensive medications and clinical inertia, and also enable multi-professional team-based management of hypertension. However, the implementation of medical telemonitoring systems in clinical practice is not easy, and substantial barriers, including the development of user-friendly devices, integration with existing clinical systems, data security, and cost of implementation and maintenance, need to be overcome. In this review, we focus on the potential of medical telemonitoring for the management of hypertension in older people in Japan.


Asunto(s)
Fragilidad , Hipertensión , Humanos , Anciano , Japón , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Determinación de la Presión Sanguínea , Antihipertensivos/uso terapéutico
14.
Intern Med ; 62(19): 2833-2837, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36792191

RESUMEN

A 70-year-old Japanese man with a submucosal gastric mass that continued to increase in size underwent endoscopic submucosal dissection using the pocket creation method. Histologically, some epithelial cell nuclei were enlarged, but there was little atypia overall and no sign of malignancy, suggesting a diagnosis of submucosal heterotopic gastric gland (SHGG). SHGG that enlarges over time has been associated with gastric cancer, but a preoperative diagnosis is difficult. This case was very valuable, as it enabled us to follow the course of SHGG over a period of about nine years, from the onset to enlargement.


Asunto(s)
Resección Endoscópica de la Mucosa , Neoplasias Gástricas , Masculino , Humanos , Anciano , Endoscopía , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Mucosa Gástrica/cirugía , Mucosa Gástrica/patología
15.
Am J Hypertens ; 36(2): 90-101, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36053278

RESUMEN

BACKGROUND: Inconsistencies between the office and out-of-office blood pressure (BP) values (described as white-coat hypertension or masked hypertension) may be attributable in part to differences in the BP monitoring devices used. METHODS: We studied consistency in the classification of BP control (well-controlled BP vs. uncontrolled BP) among office, home, and ambulatory BPs by using a validated "all-in-one" BP monitoring device. In the nationwide, general practitioner-based multicenter HI-JAMP study, 2,322 hypertensive patients treated with antihypertensive drugs underwent office BP measurements and 24-hour ambulatory BP monitoring (ABPM), consecutively followed by 5-day home BP monitoring (HBPM), for a total of seven BP measurement days. RESULTS: Using the thresholds of the JSH2019 and ESC2018 guidelines, the patients with consistent classification of well-controlled status in the office (<140 mmHg) and home systolic BP (SBP) (<135 mmHg) (n = 970) also tended to have well-controlled 24-hour SBP (<130 mmHg) (n = 808, 83.3%). The patients with the consistent classification of uncontrolled status in office and home SBP (n = 579) also tended to have uncontrolled 24-hour SBP (n = 444, 80.9%). Among the patients with inconsistent classifications of office and home BP control (n = 803), 46.1% had inconsistent ABPM-vs.-HBPM out-of-office BP control status. When the 2017 ACC/AHA thresholds were applied as an alternative, the results were essentially the same. CONCLUSIONS: The combined assessment of the office and home BP is useful in clinical practice. Especially for patients whose office BP classification and home BP classification conflict, the complementary clinical use of both HBPM and ABPM might be recommended.


Asunto(s)
Hipertensión , Hipertensión de la Bata Blanca , Humanos , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial/métodos , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Determinación de la Presión Sanguínea/métodos , Hipertensión de la Bata Blanca/diagnóstico
17.
J Chem Inf Model ; 62(17): 4057-4065, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35993595

RESUMEN

Pharmacokinetic research plays an important role in the development of new drugs. Accurate predictions of human pharmacokinetic parameters are essential for the success of clinical trials. Clearance (CL) and volume of distribution (Vd) are important factors for evaluating pharmacokinetic properties, and many previous studies have attempted to use computational methods to extrapolate these values from nonclinical laboratory animal models to human subjects. However, it is difficult to obtain sufficient, comprehensive experimental data from these animal models, and many studies are missing critical values. This means that studies using nonclinical data as explanatory variables can only apply a small number of compounds to their model training. In this study, we perform missing-value imputation and feature selection on nonclinical data to increase the number of training compounds and nonclinical datasets available for these kinds of studies. We could obtain novel models for total body clearance (CLtot) and steady-state Vd (Vdss) (CLtot: geometric mean fold error [GMFE], 1.92; percentage within 2-fold error, 66.5%; Vdss: GMFE, 1.64; percentage within 2-fold error, 71.1%). These accuracies were comparable to the conventional animal scale-up models. Then, this method differs from animal scale-up methods because it does not require animal experiments, which continue to become more strictly regulated as time passes.


Asunto(s)
Vías de Eliminación de Fármacos , Aprendizaje Automático , Animales , Humanos , Modelos Biológicos , Preparaciones Farmacéuticas
18.
PLoS One ; 17(7): e0270522, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35793335

RESUMEN

The heartwood color of a major plantation tree Cryptomeria japonica shows high variability among clones and cultivars, and brighter heartwood has higher value in the usage of non-laminated wood such as in traditional construction, which makes heartwood color an important trait in breeding of this species. However, the genetic basis of the interactions between genetics and the environment on heartwood color has been understudied while these are necessary for effective breeding programs in multiple environmental condition. The objectives of the present study were to evaluate the effects of genetics and environments on heartwood color and how they interact in contrasting environments, and to identify genomic regions controlling heartwood color in C. japonica across multiple environments. Heartwood color in terms of L*a*b* color space and spectral reflectance was measured in common gardens established in three contrasting sites. Quantitative trait loci (QTL) that affect heartwood color were identified using previously constructed highly saturated linkage maps. Results found that heartwood color was largely genetically controlled, and genotype-by-environment interaction explained one-third of the total genetic variance of heartwood color. The effect of the environment was small compared to the effect of genetics, whereas environmental effects largely varied among heartwood color traits. QTL analysis identified a large number of QTLs with small to moderate effects (phenotypic variation explained of 6.6% on average). Some of these QTLs were stably expressed in multiple environments or had pleiotropic effects on heartwood color and moisture content. These results indicated that genetic variation in phenotypic plasticity plays an important role in regulating heartwood color and that the identified QTLs would maximize the breeding efficiency of heartwood color in C. japonica in heterogeneous environments.


Asunto(s)
Cryptomeria , Sitios de Carácter Cuantitativo , Cryptomeria/genética , Interacción Gen-Ambiente , Genotipo , Fitomejoramiento
19.
DEN Open ; 2(1): e103, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35873508

RESUMEN

Objectives: Early obstruction of a self-expandable metal stent placed for distal malignant biliary obstruction is more likely to occur in the presence of duodenal invasion. An anti-reflux self-expandable metal stent (ARMS) has been developed for the purpose of preventing duodenal fluid reflux into the bile duct. In this study, we evaluated the usefulness and safety of a duckbill-type ARMS (D-ARMS) in the situation of duodenal invasion. Methods: We retrospectively analyzed 10 consecutive patients who received D-ARMS for distal malignant biliary obstruction with duodenal invasion. We evaluated non-occlusion cholangitis, recurrent biliary obstruction (RBO), and adverse events after D-ARMS placement. Results: There were no cases of non-occlusion cholangitis. RBO was observed in 2 patients (20%), and time to RBO was 236 days and 117 days, respectively. The causes of RBO were overgrowth and sludge formation. The median time to RBO was 382 days (range, 117-382 days). Only one adverse event was observed (cholecystitis). Conclusions: D-ARMS shows potential as an optimal ARMS.

20.
Sci Rep ; 12(1): 11243, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35788621

RESUMEN

Understanding the actual situation of radiocesium (137Cs) contamination of trees caused by the Fukushima nuclear accident is essential for predicting the future contamination of wood. Particularly important is determining whether the 137Cs dynamics within forests and trees have reached apparent steady state. We conducted a monitoring survey of four major tree species (Japanese cedar, Japanese cypress, konara oak, and Japanese red pine) at multiple sites. Using a dynamic linear model, we analyzed the temporal trends in 137Cs activity concentrations in the bark (whole), outer bark, inner bark, wood (whole), sapwood, and heartwood during the 2011-2020 period. The activity concentrations were decay-corrected to September 1, 2020, to exclude the decrease due to the radioactive decay. The 137Cs concentrations in the whole and outer bark samples showed an exponential decrease in most plots but a flat trend in one plot, where 137Cs root uptake is considered to be high. The 137Cs concentration ratio (CR) of inner bark/sapwood showed a flat trend but the CR of heartwood/sapwood increased in many plots, indicating that the 137Cs dynamics reached apparent steady state within one year in the biologically active parts (inner bark and sapwood) and after several to more than 10 years in the inactive part (heartwood). The 137Cs concentration in the whole wood showed an increasing trend in six plots. In four of these plots, the increasing trend shifted to a flat or decreasing trend. Overall, the results show that the 137Cs dynamics within forests and trees have reached apparent steady state in many plots, although the amount of 137Cs root uptake in some plots is possibly still increasing 10 years after the accident. Clarifying the mechanisms and key factors determining the amount of 137Cs root uptake will be crucial for predicting wood contamination.


Asunto(s)
Accidente Nuclear de Fukushima , Radioisótopos de Cesio , Corteza de la Planta , Árboles , Madera
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