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1.
Nature ; 630(8017): 660-665, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839955

RESUMO

The capacity for terrestrial ecosystems to sequester additional carbon (C) with rising CO2 concentrations depends on soil nutrient availability1,2. Previous evidence suggested that mature forests growing on phosphorus (P)-deprived soils had limited capacity to sequester extra biomass under elevated CO2 (refs. 3-6), but uncertainty about ecosystem P cycling and its CO2 response represents a crucial bottleneck for mechanistic prediction of the land C sink under climate change7. Here, by compiling the first comprehensive P budget for a P-limited mature forest exposed to elevated CO2, we show a high likelihood that P captured by soil microorganisms constrains ecosystem P recycling and availability for plant uptake. Trees used P efficiently, but microbial pre-emption of mineralized soil P seemed to limit the capacity of trees for increased P uptake and assimilation under elevated CO2 and, therefore, their capacity to sequester extra C. Plant strategies to stimulate microbial P cycling and plant P uptake, such as increasing rhizosphere C release to soil, will probably be necessary for P-limited forests to increase C capture into new biomass. Our results identify the key mechanisms by which P availability limits CO2 fertilization of tree growth and will guide the development of Earth system models to predict future long-term C storage.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Florestas , Fósforo , Microbiologia do Solo , Árvores , Biomassa , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Fósforo/metabolismo , Rizosfera , Solo/química , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Mudança Climática
2.
Nature ; 580(7802): 227-231, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269351

RESUMO

Atmospheric carbon dioxide enrichment (eCO2) can enhance plant carbon uptake and growth1-5, thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO2 concentration6. Although evidence gathered from young aggrading forests has generally indicated a strong CO2 fertilization effect on biomass growth3-5, it is unclear whether mature forests respond to eCO2 in a similar way. In mature trees and forest stands7-10, photosynthetic uptake has been found to increase under eCO2 without any apparent accompanying growth response, leaving the fate of additional carbon fixed under eCO2 unclear4,5,7-11. Here using data from the first ecosystem-scale Free-Air CO2 Enrichment (FACE) experiment in a mature forest, we constructed a comprehensive ecosystem carbon budget to track the fate of carbon as the forest responded to four years of eCO2 exposure. We show that, although the eCO2 treatment of +150 parts per million (+38 per cent) above ambient levels induced a 12 per cent (+247 grams of carbon per square metre per year) increase in carbon uptake through gross primary production, this additional carbon uptake did not lead to increased carbon sequestration at the ecosystem level. Instead, the majority of the extra carbon was emitted back into the atmosphere via several respiratory fluxes, with increased soil respiration alone accounting for half of the total uptake surplus. Our results call into question the predominant thinking that the capacity of forests to act as carbon sinks will be generally enhanced under eCO2, and challenge the efficacy of climate mitigation strategies that rely on ubiquitous CO2 fertilization as a driver of increased carbon sinks in global forests.


Assuntos
Atmosfera/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Sequestro de Carbono , Florestas , Árvores/metabolismo , Biomassa , Eucalyptus/crescimento & desenvolvimento , Eucalyptus/metabolismo , Aquecimento Global/prevenção & controle , Modelos Biológicos , New South Wales , Fotossíntese , Solo/química , Árvores/crescimento & desenvolvimento
3.
Circ J ; 87(8): 1058-1067, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37344406

RESUMO

BACKGROUND: The association between the T-peak to T-end interval (Tp-e) and ventricular arrhythmia (VA) events in cardiac sarcoidosis (CS) is unknown. The purpose of this study was to investigate whether Tp-e was associated with VA events in CS patients with implantable cardioverter defibrillators (ICDs) or cardiac resynchronization therapy defibrillators (CRT-Ds).Methods and Results: We retrospectively studied 50 patients (16 men; mean [±SD] age 56.3±10.5 years) with CS and ICD/CRT-D. The maximum Tp-e in the precordial leads recorded by a 12-lead electrocardiogram after ICD/CRT-D implantation was evaluated. The clinical endpoint was defined as appropriate ICD therapy. During a median follow-up period of 85.0 months, 22 patients underwent appropriate therapy and 10 patients died. Kaplan-Meier analysis revealed that the probability of the clinical endpoint was 28.3% at 2 years and 35.3% at 4 years. The optimal cut-off value of the Tp-e for the prediction of the clinical endpoint was 91 ms, with a sensitivity of 72.7% and a specificity of 87.0% (area under the curve=0.81). Multivariate Cox regression analysis showed that Tp-e ≥91 ms (hazard ratio [HR] 5.10; 95% confidence interval [CI] 1.99-13.1; P<0.001) and a histological diagnosis of CS (HR 3.84; 95% CI 1.28-11.5; P=0.016) were significantly associated with the clinical endpoint. CONCLUSIONS: Tp-e ≥91 ms was a significant predictor of VA events in patients with CS and ICD/CRT-D.


Assuntos
Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Insuficiência Cardíaca , Sarcoidose , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Arritmias Cardíacas/terapia , Terapia de Ressincronização Cardíaca/efeitos adversos , Sarcoidose/terapia , Resultado do Tratamento , Insuficiência Cardíaca/terapia
4.
Pacing Clin Electrophysiol ; 46(3): 264-267, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36161665

RESUMO

A 63-year-old man was admitted to the hospital due to ventricular tachycardia (VT) undersensing, caused by decreased R-wave amplitude in a cardiac resynchronization therapy defibrillator. The R-wave amplitude of VT sensed by the left ventricular (LV) lead was markedly higher than that by the right ventricular (RV) lead; therefore, we reconnected the IS-1 RV lead to the LV IS-1 port and the IS-1 LV lead to the RV IS-1 port to resolve this issue. After discharge, it was confirmed that VT was successfully terminated by the second sequence of intrinsic ATP (iATP, Medtronic, Minneapolis, MN, USA) from the LV lead.


Assuntos
Terapia de Ressincronização Cardíaca , Taquicardia Ventricular , Masculino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento , Taquicardia Ventricular/terapia , Arritmias Cardíacas , Desfibriladores
5.
BMC Nephrol ; 24(1): 1, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597041

RESUMO

BACKGROUND: The improvement of anaemia over time by erythropoiesis stimulating agent (ESA) is associated with better survival in haemodialysis patients. We previously reported that erythrocyte creatine content, a marker of erythropoietic capacity, was a reliable marker to estimate the effectiveness of ESA. The aim of this study was to examine the accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in haemodialysis patients. METHODS: ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the study period. Erythrocyte creatine content and haematologic indices were measured at baseline in 92 patients receiving maintenance haemodialysis. Haemoglobin was also measured 3 months after. Improvement of anaemia was defined as ≥ 0.8 g/dL change in haemoglobin from baseline to 3 months. RESULTS: Erythrocyte creatine content was significantly higher in 32 patients with improvement of anaemia compared to 60 patients with no improvement of anaemia (2.47 ± 0.74 vs. 1.57 ± 0.49 µmol/gHb, P = 0.0001). When 9 variables (erythrocyte creatine content, ESA dose, reticulocyte, haptoglobin, haemoglobin at baseline, serum calcium, intact parathyroid hormone, transferrin saturation and serum ferritin) were used in the multivariate logistic regression analysis, erythrocyte creatine emerged as the most important variable associated with the improvement of anaemia (P = 0.0001). The optimal cut-off point of erythrocyte creatine content to detect the improvement of anaemia was 1.78 µmol/gHb (Area under the curve: 0.86). Sensitivity and specificity of erythrocyte creatine content to detect the improvement of anaemia were 90.6% and 83.3%. CONCLUSION: Erythrocyte creatine content is a reliable marker to predict the improvement of anaemia 3 months ahead in patients receiving maintenance haemodialysis.


Assuntos
Anemia , Eritropoetina , Hematínicos , Oxibato de Sódio , Humanos , Creatina , Anemia/diagnóstico , Anemia/etiologia , Anemia/terapia , Eritrócitos/química , Diálise Renal/efeitos adversos , Hematínicos/uso terapêutico , Hemoglobinas/análise
6.
J Environ Manage ; 337: 117713, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36958277

RESUMO

Roughly 2 billion ha of land are degraded and in need of ecological restoration worldwide. Active restoration frequently involves revegetation, which leads to the dilemma of whether to conduct direct seeding or to plant nursery-grown seedlings. The choice of revegetation method can regulate plant survival and performance, with economic implications that ultimately feed back to our capacity to conduct restoration. We followed a peer-reviewed protocol to develop a systematic map that collates, describes and catalogues the available studies on how seeding compares to planting in achieving restoration targets. We compiled a database with the characteristics of all retrieved studies, which can be searched to identify studies of particular locations and habitats, objectives of restoration, plant material, technical aspects, and outcomes measured. The search was made in eight languages and retrieved 3355 publications, of which 178 were retained. The systematic map identifies research gaps, such as a lack of studies in the global South, in tropical rainforests, and covering a long time period, which represent opportunities to expand field-based research. Additionally, many studies overlooked reporting on important technical aspects such as seed provenance and nursery cultivation methods, and others such as watering or seedling protection were more frequently applied for planting than for seeding, which limits our capacity to learn from past research. Most studies measured outcomes related to the target plants but avoided measuring general restoration outcomes or economic aspects. This represents a relevant gap in research, as the choice of revegetation method is greatly based on economic aspects and the achievement of restoration goals goes beyond the establishment of plants. Finally, we identified a substantial volume of studies conducted in temperate regions and over short periods (0-5 y). This research cluster calls for a future in-depth synthesis, potentially through meta-analysis, to reveal the overall balance between seeding and planting and assess whether the response to this question is mediated by species traits, environmental characteristics, or technical aspects. Besides identifying research clusters and gaps, the systematic map database allows managers to find the most relevant scientific literature on the appropriateness of seeding vs. planting for particular conditions, such as certain species or habitats.


Assuntos
Ecossistema , Plantas , Plântula , Sementes
7.
Int Heart J ; 64(6): 1095-1104, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37967983

RESUMO

Patients with persistent heart failure (HF) with reduced ejection fraction (HFrEF) have a poorer prognosis than those with HF with improved ejection fraction (HFimpEF). However, data on the predictive value of echocardiographic parameters for persistent HFrEF are lacking. We retrospectively studied 443 patients who were diagnosed with HFrEF (EF ≤ 40%) during hospitalization and underwent echocardiography at the 1-year follow-up. We divided them into the 2 groups: HFimpEF (EF > 40%) and persistent HFrEF group at 1-year follow-up, and assessed the predictive value of echocardiographic parameters at discharge for persistent HFrEF. In total, 301/443 patients (68%) were diagnosed with persistent HFrEF and 142/443 (32%) with HFimpEF at the 1-year follow-up. Kaplan-Meier analysis revealed that the persistent HFrEF group had a poorer prognosis than the HFimpEF group (log-rank, P < 0.001). Receiver operating characteristic curve analysis revealed that left ventricular end-systolic diameter (LVESD) had the highest area under the curve (AUC) (0.70; 95% confidence interval [CI]: 0.64-0.75; cutoff value: 55 mm) among various echocardiographic parameters. LVESD was an independent predictor of persistent HFrEF at the 1-year follow-up (odds ratio: 1.07, 95%CI: 1.02-1.12) upon multivariable logistic regression analysis. The incidence of persistent HFrEF was higher in patients with an LVESD ≥ 55 mm than in those with an LVESD < 55 mm (81% versus 55%, Fisher's exact test, P < 0.001). In conclusion, an LVESD (≥ 55 mm) was associated with persistent HFrEF. Focusing on LVESD in daily practice may help clinicians with risk stratification for decision-making regarding management in patients with advanced HF refractory to guideline-directed medical therapy.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/complicações , Volume Sistólico , Estudos Retrospectivos , Prognóstico , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda
8.
BMC Nephrol ; 22(1): 413, 2021 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-34895154

RESUMO

BACKGROUND: One of the main causes of anaemia in patients with end-stage renal disease is relative deficiency in erythropoietin production. Eythropoiesis stimulating agent (ESA), a potent haematopoietic growth factor, is used to treat anaemia in haemodialysis patients. The effect of ESA is usually assessed by haematological indices such as red blood cell count, haemoglobin concentration and haematocrit, but erythrocyte indices do not provide information of the rapid change in erythropoietic activity. As erythrocyte creatine directly assess erythropoiesis, the aim of this study was to evaluate the effect of ESA in haemodialysis patients by measuring the erythrocyte creatine content. METHODS: ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the entire study period. Erythrocyte creatine was measured with haematologic indices in 83 haemodialysis patients. Haemoglobin was also measured 3 months after. RESULTS: ESA dose (152.4 ± 62.9 vs. 82.2 ± 45.5 units/kg/week, P = 0.0001) and erythrocyte creatine (2.07 ± 0.73 vs. 1.60 ± 0.41 µmol/gHb, p = 0.0003) were significantly higher in 27 patients with haemoglobin <10 g/dL compared to 56 patients with haemoglobin ≥10 g/dL. There was a fair correlation between ESA dose and the concentration of creatine in the erythrocytes (r = 0.55, P < 0.0001). Increase in haemoglobin (>0.1 g/dL) was observed in 37 patients, whereas haemoglobin did not increase in 46 patients. Erythrocyte creatine levels were significantly higher in those patients with an increase in haemoglobin compared to those without (2.04 ± 0.64 vs. 1.52 ± 0.39 µmol/gHb, p < 0.0001). When 8 variables (ESA dose, erythropoietin resistance index, C-reactive protein, intact parathyroid hormone, iron supplementation, presence of anaemia, erythrocyte creatine and reticulocyte) were used in the multivariate logistic analysis, erythrocyte creatine levels emerged as the most important variable associated with increase in haemoglobin (Chi-square = 6.19, P = 0.01). CONCLUSION: Erythrocyte creatine, a useful marker of erythropoietic capacity, is a reliable marker to estimate ameliorative effectiveness of ESA in haemodialysis patients.


Assuntos
Anemia/tratamento farmacológico , Creatina/análise , Eritrócitos/química , Eritropoetina/uso terapêutico , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
9.
Int J Cancer ; 147(11): 3224-3235, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818320

RESUMO

The cystine/glutamate antiporter, system xc- , is essential for the efficient uptake of cystine into cells. Interest in the mechanisms of system xc- function soared with the recognition that system xc- presents the most upstream node of ferroptosis, a recently described form of regulated necrosis relevant for degenerative diseases and cancer. Since targeting system xc- hold the great potential to efficiently combat tumor growth and metastasis of certain tumors, we disrupted the substrate-specific subunit of system xc- , xCT (SLC7A11) in the highly metastatic mouse B16F10 melanoma cell line and assessed the impact on tumor growth and metastasis. Subcutaneous injection of tumor cells into the syngeneic B16F10 mouse melanoma model uncovered a marked decrease in the tumor-forming ability and growth of KO cells compared to control cell lines. Strikingly, the metastatic potential of KO cells was markedly reduced as shown in several in vivo models of experimental and spontaneous metastasis. Accordingly, survival rates of KO tumor-bearing mice were significantly prolonged in contrast to those transplanted with control cells. Analyzing the in vitro ability of KO and control B16F10 cells in terms of endothelial cell adhesion and spheroid formation revealed that xCT expression indeed plays an important role during metastasis. Hence, system xc- emerges to be essential for tumor metastasis in mice, thus qualifying as a highly attractive anticancer drug target, particularly in light of its dispensable role for normal life in mice.


Assuntos
Sistema y+ de Transporte de Aminoácidos/genética , Técnicas de Inativação de Genes/métodos , Melanoma/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/genética , Camundongos , Metástase Neoplásica , Transplante de Neoplasias , Taxa de Sobrevida
10.
Zygote ; 27(5): 329-336, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31412969

RESUMO

Mammalian Pou5f1 encodes the POU family class V (POU-V) transcription factor which is essential for the pluripotency of embryonic cells and germ cells. In vertebrates, various POU-V family genes have been identified and classified into the POU5F1 family or its paralogous POU5F3 family. In this study, we cloned two cDNAs named CpPou5f1 and CpPou5f3, which encode POU-V family proteins of the Japanese red bellied newt Cynops pyrrhogaster. In the predicted amino acid sequence encoded by CpPou5f1, the typical MAGH sequence at the N-terminus and deletion of arginine at the fifth position of POU-homeodomain were recognized, but not in the sequence encoded by CpPou5f3. Phylogenetic analysis using Clustal Omega software indicated that CpPou5f1 and CpPou5f3 are classified into the clade of the POU5F1 and POU5F3 families, respectively. In a real-time polymerase chain reaction (RT-PCR) analysis, the marked gene expression of CpPou5f1 was observed during oogenesis and early development up to the tail-bud stage, whereas weak gene expression of CpPou5f3 was detected only in the early stages of oogenesis and gastrula. In adult organs, CpPou5f1 was expressed only in the ovary, while gene expression of CpPou5f3 was recognized in various organs. A regeneration experiment using larval forelimb revealed that transient gene expression of CpPou5f1 occurred at the time of wound healing, followed by gene activation of CpPou5f3 during the period of blastema formation. These results suggest that CpPou5f1 and CpPou5f3 might play different roles in embryogenesis and limb regeneration.


Assuntos
Oogênese/genética , Fatores do Domínio POU/genética , Regeneração/genética , Salamandridae/genética , Animais , Embrião não Mamífero/fisiologia , Extremidades/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Família Multigênica , Filogenia , Salamandridae/embriologia , Salamandridae/fisiologia
11.
Opt Express ; 26(21): 27865-27872, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469844

RESUMO

An efficient preparation process for Al hole array structures emitting wavelength-selective thermal radiation that is based on the anisotropic anodic etching of Al was demonstrated. The formation of an ordered hole array was achieved by a masking process prior to the anodic etching. The present process allows the preparation of large samples because the masking of the Al foil has a high throughput owing to the simple printing process using a flexible stamp. The thermal radiation properties of the Al hole array could be controlled by adjusting the depth and aperture size of the holes.

12.
Glob Chang Biol ; 22(4): 1628-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26546164

RESUMO

Free-air CO2 enrichment (FACE) experiments have demonstrated increased plant productivity in response to elevated (e)CO2, with the magnitude of responses related to soil nutrient status. Whilst understanding nutrient constraints on productivity responses to eCO2 is crucial for predicting carbon uptake and storage, very little is known about how eCO2 affects nutrient cycling in phosphorus (P)-limited ecosystems. Our study investigates eCO2 effects on soil N and P dynamics at the EucFACE experiment in Western Sydney over an 18-month period. Three ambient and three eCO2 (+150 ppm) FACE rings were installed in a P-limited, mature Cumberland Plain Eucalyptus woodland. Levels of plant accessible nutrients, evaluated using ion exchange resins, were increased under eCO2, compared to ambient, for nitrate (+93%), ammonium (+12%) and phosphate (+54%). There was a strong seasonality to responses, particularly for phosphate, resulting in a relatively greater stimulation in available P, compared to N, under eCO2 in spring and summer. eCO2 was also associated with faster nutrient turnover rates in the first six months of the experiment, with higher N (+175%) and P (+211%) mineralization rates compared to ambient rings, although this difference did not persist. Seasonally dependant effects of eCO2 were seen for concentrations of dissolved organic carbon in soil solution (+31%), and there was also a reduction in bulk soil pH (-0.18 units) observed under eCO2. These results demonstrate that CO2 fertilization increases nutrient availability - particularly for phosphate - in P-limited soils, likely via increased plant belowground investment in labile carbon and associated enhancement of microbial turnover of organic matter and mobilization of chemically bound P. Early evidence suggests that there is the potential for the observed increases in P availability to support increased ecosystem C-accumulation under future predicted CO2 concentrations.


Assuntos
Dióxido de Carbono/análise , Eucalyptus , Nitrogênio/análise , Fósforo/análise , Solo/química , Ecossistema , Florestas , Concentração de Íons de Hidrogênio , Resinas de Troca Iônica , Membranas Artificiais , New South Wales , Estações do Ano
13.
Jpn J Ophthalmol ; 68(5): 562-570, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39207651

RESUMO

PURPOSE: To compare surgical results between ab-externo microshunt surgery and trabeculectomy, focusing on postoperative corneal astigmatism. STUDY DESIGN: Retrospective study. METHODS: Subjects were patients with glaucoma who underwent either standalone ab-externo microshunt surgery or trabeculectomy. Data on ophthalmic examinations obtained preoperatively and 1, 3, and 5 months postoperatively were analyzed. To assess corneal astigmatism, two separate data sets measured by anterior segment optical coherence tomography and autorefractometer were evaluated. Multivariate linear mixed model analyses were conducted to identify factors associated with the astigmatism changes. RESULTS: Sixty eyes were examined: 13 eyes underwent microshunt surgery, and 47 eyes underwent trabeculectomy. The total corneal astigmatism measurements by anterior segment optical coherence tomography (AS-OCT) were: - 1.15 ± 0.85 D and - 1.17 ± 0.81 D for the microshunt and trabeculectomy groups, respectively, preoperatively. At five months postoperatively they were - 0.92 ± 0.47 D and - 1.61 ± 0.83 D, respectively (P = 0.807 for the microshunt group and P = 0.005 for the trabeculectomy group: Wilcoxon signed-rank test). AS-OCT also indicated similar results for posterior corneal astigmatism. Autorefractometry also found the total corneal astigmatism was significantly changed only in the trabeculectomy group. The linear mixed model analysis revealed that trabeculectomy (P = 0.001), older age (P = 0.004), and longer postoperative period (P = 0.015) were correlated with greater astigmatism changes. The intraocular pressures significantly decreased following both surgical treatments. CONCLUSIONS: Standalone ab-externo microshunt surgery has less effect on corneal astigmatism during a 5 month period than trabeculectomy. Both surgical procedures significantly reduced intraocular pressure.


Assuntos
Astigmatismo , Glaucoma , Pressão Intraocular , Tomografia de Coerência Óptica , Trabeculectomia , Acuidade Visual , Humanos , Astigmatismo/fisiopatologia , Astigmatismo/cirurgia , Astigmatismo/diagnóstico , Trabeculectomia/métodos , Estudos Retrospectivos , Masculino , Feminino , Tomografia de Coerência Óptica/métodos , Pressão Intraocular/fisiologia , Idoso , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Glaucoma/cirurgia , Glaucoma/fisiopatologia , Glaucoma/diagnóstico , Seguimentos , Córnea/cirurgia , Córnea/diagnóstico por imagem , Complicações Pós-Operatórias , Resultado do Tratamento , Microcirurgia/métodos , Fatores de Tempo , Idoso de 80 Anos ou mais
14.
J Arrhythm ; 40(3): 639-642, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38939789

RESUMO

A 26-year-old man with long QT syndrome (LQTS) underwent subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation. The patient exhibited sinus bradycardia relative to his age. The heart rate decreased, and the QT interval became longer with the administration of ß-blockers, the first-line therapy for LQTS. The patient experienced frequent S-ICD discharges. Subsequently, a single-chamber pacemaker was implanted, and the 12-lead electrocardiogram showed atrial pacing and ventricular sensing at 60 beats per minute with a shorter QTc interval. After converting to "double-device therapy," the patient did not experience any ventricular arrhythmia events.

15.
J Thorac Dis ; 16(2): 1702-1714, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38505041

RESUMO

Background and Objective: Treatment for atrial fibrillation (AF) has evolved significantly, with pulmonary vein isolation (PVI) becoming an established treatment. However, the outcomes following catheter ablation for persistent AF remain unsatisfactory. Hybrid catheter-surgical ablation has emerged as a therapeutic approach for persistent AF, combining the strengths of both interventions. The purpose of this narrative review is to comprehensively examine the current state of knowledge regarding hybrid ablation for AF. Methods: A thorough PubMed search using the terms "hybrid ablation", "atrial fibrillation", "catheter ablation", and "guideline on cardiology" within the timeframe of 1980 to 2024 resulted in 138,969 articles. Consensus on the selected articles was reached through a series of structured meetings and discussions. Key Content and Findings: PVI has demonstrated higher sinus rhythm maintenance rates, especially for paroxysmal AF. However, the efficacy is not as high for persistent AF. Additional ablation strategies, such as linear ablation, complex fractionated atrial electrogram ablation, low voltage zone ablation as well as posterior wall isolation, lack consistent evidence of effectiveness. Hybrid ablation, involving collaboration between cardiac surgeons and electrophysiologists, presents a promising alternative for hard-to-treat AF. Recent studies report favorable outcomes of hybrid ablation, with atrial arrhythmia-free rates ranging from 53.5% to 76%, surpassing those of catheter ablation alone, which might result from better lesion durability or intervention for non-PV foci and left atrial appendage excision or closure during hybrid ablation. The rate of complications associated with hybrid ablation is higher than catheter ablation alone. Conclusions: While favorable outcomes of hybrid ablation for persistent AF have been reported, it is not recommended for all AF patients due to its invasiveness compared to catheter ablation. Additionally, some patients with persistent AF maintain sinus rhythm with catheter ablation alone. More clinical data are needed to determine which patients are suitable candidates for hybrid ablation.

16.
JACC Adv ; 3(8): 101120, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39156115

RESUMO

Background: Managing heart rate (HR) is crucial for enhancing clinical prognosis in patients with heart failure (HF) and atrial fibrillation (AF). Nevertheless, the prognostic impact of HR at discharge in hospitalized HF patients remains unclear. Objectives: This study aimed to determine the HR associated with the lowest risk of death and HF in patients hospitalized with HF and AF. Methods: In this observational study, 334 persistent AF patients were analyzed from a database of 1,930 consecutive HF hospitalizations. Exclusion criteria included sinus rhythm or paroxysmal AF, cardiac pacemakers, or unrecorded HR at discharge. Participants were divided into four groups based on HR at discharge in 10 beats/min increments. The primary endpoint was a composite of death from any cause and rehospitalization due to HF. The association between resting HR and the primary endpoint was determined using Kaplan-Meier analysis and Cox proportional hazards models. Results: The median follow-up period was 389 days, with 133 patients (39.8%) reaching the primary endpoint. Kaplan-Meier analysis revealed a significantly higher primary endpoint incidence in patients with HR >81 beats/min at discharge compared to those with HR <60 beats/min (log-rank test for trend: P = 0.039). Multivariable Cox regression analysis showed that HR >81 beats/min at discharge was associated with the primary endpoint, with a hazard ratio of 1.79 (95% CI: 1.04-3.07), compared to HR <60 beats/min. Conclusions: The findings suggest that controlling HR to less than 80 beats/min at discharge may lead to better clinical outcomes in patients with HF and persistent AF.

17.
Sci Adv ; 10(27): eadl5822, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38959317

RESUMO

The importance of phosphorus (P) in regulating ecosystem responses to climate change has fostered P-cycle implementation in land surface models, but their CO2 effects predictions have not been evaluated against measurements. Here, we perform a data-driven model evaluation where simulations of eight widely used P-enabled models were confronted with observations from a long-term free-air CO2 enrichment experiment in a mature, P-limited Eucalyptus forest. We show that most models predicted the correct sign and magnitude of the CO2 effect on ecosystem carbon (C) sequestration, but they generally overestimated the effects on plant C uptake and growth. We identify leaf-to-canopy scaling of photosynthesis, plant tissue stoichiometry, plant belowground C allocation, and the subsequent consequences for plant-microbial interaction as key areas in which models of ecosystem C-P interaction can be improved. Together, this data-model intercomparison reveals data-driven insights into the performance and functionality of P-enabled models and adds to the existing evidence that the global CO2-driven carbon sink is overestimated by models.


Assuntos
Ciclo do Carbono , Dióxido de Carbono , Eucalyptus , Florestas , Fósforo , Eucalyptus/metabolismo , Dióxido de Carbono/metabolismo , Fósforo/metabolismo , Fotossíntese , Mudança Climática , Ecossistema , Carbono/metabolismo , Modelos Teóricos , Sequestro de Carbono
18.
J Arrhythm ; 39(3): 454-463, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37324755

RESUMO

Background: The long-term relationship between fracture-prone implantable cardioverter-defibrillator (ICD) leads and poor prognosis remains unclear in Japanese patients. Methods: We conducted a retrospective review of the records of 445 patients who underwent implantation of advisory/Linox leads (Sprint Fidelis, 118; Riata, nine; Isoline, 10; Linox S/SD, 45) and non-advisory leads (Endotak Reliance, 33; Durata, 199; Sprint non-Fidelis, 31) between January 2005 and June 2012 at our hospital. The primary outcomes were all-cause mortality and ICD lead failure. The secondary outcomes were cardiovascular mortality, heart failure (HF) hospitalization, and the composite outcome of cardiovascular mortality and HF hospitalization. Results: During the follow-up period (median, 8.6 [4.1-12.0] years), there were 152 deaths: 61 (34%) in patients with advisory/Linox leads and 91 (35%) in those with non-advisory leads. There were 32 ICD lead failures: 27 (15%) in patients with advisory/Linox leads and five (2%) in those with non-advisory leads. Multivariate analysis for ICD lead failure demonstrated that the advisory/Linox leads had a 6.65-fold significantly greater risk of ICD lead failure than non-advisory leads. Congenital heart disease (hazard ratio 2.51; 95% confidence interval 1.08-5.83; p = .03) could also independently predict ICD lead failure. Multivariate analysis for all-cause mortality demonstrated no significant association between advisory/Linox leads and all-cause mortality. Conclusions: Patients who have implanted fracture-prone ICD leads should be carefully followed up for ICD lead failure. However, these patients have a long-term survival rate comparable with that of patients with non-advisory ICD leads in Japanese patients.

19.
Plant Biotechnol (Tokyo) ; 39(2): 119-128, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35937538

RESUMO

In rice, the lysin motif (LysM) receptor-like kinase OsCERK1, originally identified as the essential molecule for chitin-triggered immunity, plays a key role in arbuscular mycorrhizal (AM) symbiosis. As we previously reported, although AM colonization was largely repressed at 2 weeks after inoculation (WAI), arbuscules were observed at 5 WAI in oscerk1 mutant. Conversely, most mutant plants that defect the common symbiosis signaling pathway exhibited no arbuscule formation. Concerning the reason for this characteristic phenotype of oscerk1, we speculated that OsRLK10, which is a putative paralog of OsCERK1, may have a redundant function in AM symbiosis. The protein sequences of these two genes are highly conserved and it is estimated that the gene duplication occurred 150 million years ago. Here we demonstrated that OsCERK2/OsRLK10 induced AM colonization and chitin-triggered reactive oxygen species production in oscerk1 knockout mutant as similar to OsCERK1. The oscerk2 mutant showed a slight but significant reduction of AM colonization at 5 WAI, indicating the contribution of OsCERK2 for AM symbiosis. However, the oscerk2;oscerk1 double-knockout mutant produced arbuscules at 5 WAI as similar to the oscerk1 mutant, indicating that the redundancy of OsCERK1 and OsCERK2 did not explain the mycorrhizal colonization in oscerk1 at 5 WAI. These results indicated that OsCERK2 has a potential to regulate both chitin-triggered immunity and AM symbiosis and at least partially contributes to AM symbiosis in rice though the contribution of OsCERK2 appears to be weaker than that of OsCERK1.

20.
Gen Thorac Cardiovasc Surg ; 70(2): 178-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34716879

RESUMO

Left coronary artery malperfusion is a fatal complication of acute type A aortic dissection. However, effective treatment strategies have not yet been established. Herein, we report two cases of left coronary artery malperfusion successfully treated with different preoperative catheter interventions, followed by a central aortic repair. Preoperative coronary intervention ensuring the blood flow to the left coronary artery might be essential if a coronary angiogram was performed prior to the diagnosis and treatment.


Assuntos
Dissecção Aórtica , Doença Aguda , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Humanos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares
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