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1.
Plant Biol (Stuttg) ; 25(5): 687-695, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37070345

RESUMEN

The reproductive characteristics of understory bamboo and the effects of dieback on overstory tree seedlings through temporal changes in the environment at the forest floor have only been examined in a few bamboo species, due to the unpredictable occurrence of flowering events and long intervals between them but provide valuable information on tree regeneration and succession in a forest with dense dwarf bamboo cover. We investigated environmental conditions and assessed seedlings (< 30-cm tall) of the dwarf bamboo Sasa borealis and overstory tree species at 44-50 measurement points during 2016-2021, which included a S. borealis mass flowering event in 2017. We also conducted seed germination tests to determine germination rates and patterns in S. borealis. Environmental factors affecting seedling recruitment of S. borealis and of overstory trees were analysed using spatiotemporal generalized linear mixed models in the Bayesian framework. We observed gradual temporal changes in the environment, including increasing canopy openness and decreasing maximum height of dead S. borealis culms. The seeds germinated slowly and the emergence of current-year S. borealis seedlings peaked in spring-summer in 2019. The tree seedling density after 2019 increased significantly compared to that before the dieback. The model results suggest that tree seedling establishment was enhanced by increased light availability. Continuous field observation beginning before S. borealis dieback revealed gradually enhanced tree recruitment in response to slow decay of the remaining dead culms and slow recovery of S. borealis. The seedling regeneration pattern of understory bamboo partly contributes to a prolonged opportunity for overstory tree regeneration.


Asunto(s)
Bosques , Plantones , Japón , Teorema de Bayes , Plantones/fisiología , Germinación , Ecosistema
2.
Phys Rev Lett ; 128(7): 072501, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35244436

RESUMEN

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470

3.
BJS Open ; 5(4)2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34355240

RESUMEN

BACKGROUND: Hepatectomy with vascular resection (VR) for perihilar cholangiocarcinoma (PHCC) is a challenging procedure. However, only a few reports on this procedure have been published and its clinical significance has not been fully evaluated. METHODS: Patients undergoing surgical resection for PHCC from 2002-2017 were studied. The surgical outcomes of VR and non-VR groups were compared. RESULTS: Some 238 patients were included. VR was performed in 85 patients. The resected vessels were hepatic artery alone (31 patients), portal vein alone (37 patients) or both (17 patients). The morbidity rates were almost the same in the VR (49.4 per cent) and non-VR (43.8 per cent) groups (P = 0.404). The mortality rates of VR (3.5 per cent) and non-VR (3.3 per cent) were also comparable (P > 0.999). The median survival time (MST) was 45 months in the non-VR group and 36 months in VR group (P = 0.124). Among patients in whom tumour involvement was suspected on preoperative imaging and whose carbohydrate antigen 19-9 (CA19-9) value was 37 U/ml or less, MST in the VR group was significantly longer than that in the non-VR group (50 versus 34 months, P = 0.017). In contrast, when the CA19-9 value was greater than 37 U/ml, MST of the VR and non-VR groups was comparable (28 versus 29 months, P = 0.520). CONCLUSION: Hepatectomy with VR for PHCC can be performed in a highly specialized hepatobiliary centre with equivalent short- and long-term outcomes to hepatectomy without VR.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos , Colangiocarcinoma/cirugía , Hepatectomía , Humanos , Tumor de Klatskin/cirugía
4.
AJNR Am J Neuroradiol ; 42(5): 955-960, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33632737

RESUMEN

BACKGROUND AND PURPOSE: The signal intensity of the thyroid in neonates is high on T1WI. It is affected by gestational and postnatal ages. However, the extent of the influence of these ages is unknown. This study investigated the relationship of signal intensities of the infant thyroid with postnatal and gestational ages and anterior pituitary using 3D gradient-echo T1WI. MATERIALS AND METHODS: This retrospective study included 183 T1-weighted images from 181 infants. Using a multiple linear regression analysis, we evaluated the effects of postnatal and gestational ages on the thyroid-muscle signal intensity ratio. The relationship between the thyroid and anterior pituitary signal intensities on T1WI and the age of the infants was evaluated. RESULTS: Multiple linear regression analysis showed that the thyroid signal intensity was affected negatively by postnatal age at examination and positively by gestational age at birth (P < .01 and P = .04, respectively). According to the standardized partial regression coefficients, the influence of postnatal age at examination was stronger than that of gestational age at birth (-0.72 and 0.13, respectively). The thyroid and anterior pituitary signal intensities reached constant values at 12 weeks' postnatal age, and the mean thyroid-anterior pituitary signal intensity ratios were almost 1 throughout the entire period. CONCLUSIONS: The signal intensity of the infant thyroid on T1WI was more strongly influenced by the postnatal age at examination than the gestational age at birth, and it was almost equal to that of the anterior pituitary.


Asunto(s)
Edad Gestacional , Imagen por Resonancia Magnética/métodos , Glándula Tiroides/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Recién Nacido , Masculino , Hipófisis/diagnóstico por imagen , Estudios Retrospectivos
5.
J Stomatol Oral Maxillofac Surg ; 122(1): 56-61, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32302797

RESUMEN

INTRODUCTION: The assessment of facial symmetry, after mandibular reconstruction, currently relies on subjective esthetic assessment by an evaluator. The present study aimed to compare conventional subjective assessment with quantitative evaluation by three-dimensional (3D) stereophotogrammetry of facial cosmetic symmetry. METHODS: This retrospective study enrolled 20 patients who underwent mandibular reconstruction with free fibula flap after segmental resection between 2014 and 2018. Subjective assessments were performed by seven clinicians at 6-12 months after surgery. Simultaneously, lower face symmetry was measured by 3D stereophotogrammetry with the VECTRA H1 system and recorded as the root mean square deviation (RMSD). Data from the subjective and quantitative evaluations were compared using Spearman's rank correlation coefficient. RESULTS: The results showed that subjective assessments were strongly and negatively correlated with RMSD (P=0.00000128). This confirmed that RMSD, obtained by 3D stereophotogrammetry, reflected the subjective assessment of symmetry in our cohort. CONCLUSIONS: Three-dimensional stereophotogrammetry of facial cosmetic symmetry will be an available quantitative method for patients with head and neck cancer after mandibular reconstruction.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Reconstrucción Mandibular , Humanos , Fotogrametría , Estudios Retrospectivos
8.
Nature ; 571(7765): E7, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31263274

RESUMEN

Change history: In this Article, the original affiliation 2 was not applicable and has been removed. In addition, in the Acknowledgements there was a statement missing and an error in a name. These errors have been corrected online.

9.
Nature ; 568(7753): 487-492, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31019327

RESUMEN

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 108 and 1.3 × 1010 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth's deep mantle than previously estimated.


Asunto(s)
Dióxido de Carbono/análisis , Secuestro de Carbono , Sedimentos Geológicos/química , Biomasa , Isótopos de Carbono , Costa Rica , Sedimentos Geológicos/microbiología , Helio
11.
Clin Radiol ; 74(2): 167.e1-167.e7, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30471748

RESUMEN

AIM: To compare the performance of machine learning using multiparametric magnetic resonance imaging (mp-MRI) and positron-emission tomography (PET) to distinguish between uterine sarcoma and leiomyoma. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and informed consent was waived. Sixty-seven consecutive patients with uterine sarcoma or leiomyoma who underwent pelvic 3 T MRI and PET were included. Of 67 patients, 11 had uterine sarcomas and 56 had leiomyomas. Seven different parameters were measured in the tumours, from T2-weighted, T1-weighted, contrast-enhanced, and diffusion-weighted MRI, and PET. The areas under the receiver operating characteristic curves (AUC) with a leave-one-out cross-validation were used to compare the diagnostic performances of the univariate and multivariate logistic regression (LR) model with those of two board-certified radiologists. RESULTS: The AUCs of the univariate models using MRI parameters (0.68-0.8) were inferior to that of the maximum standardised uptake value (SUVmax) of PET (0.85); however, the AUC of the multivariate LR model (0.92) was superior to that of SUVmax, and comparable to that of the board-certified radiologists (0.97 and 0.89). CONCLUSION: The diagnostic performance of the machine learning using mp-MRI was superior to PET and comparable to that of experienced radiologists.


Asunto(s)
Fluorodesoxiglucosa F18 , Leiomioma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Sarcoma/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Aprendizaje Automático , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Útero/diagnóstico por imagen , Adulto Joven
12.
Transplant Proc ; 50(8): 2388-2391, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30316363

RESUMEN

OBJECTIVES: We investigated the correlation between class II HLA epitope mismatch and antibody-mediated rejection (AMR) episodes in kidney transplant recipients. In patients with AMR, epitope mismatch was also examined for each class II HLA mismatch to determine development of de novo donor-specific antibodies (DSAs). METHODS: We conducted a retrospective study of 167 kidney recipients. The numbers of eplet mismatches were compared between those with (n = 12) and without (n = 155) AMR, and the numbers of eplet mismatches for each type of mismatch in class II HLA among the AMR patients was also compared. RESULTS: Twelve AMR episodes were diagnosed. The total number of eplet mismatches in AMR patients with either HLA-DR or HLA-DQ was greater than those in non-AMR patients (P = .0085 and P = .0041, respectively), though the incidence of HLA class II (DRB1 + DQB) mismatch was not significantly different between the groups (P = .095). The rate of non-AMR status in patients with ≥15 was lower than those with <15 HLA class II (DR or DQ) eplet mismatches (P = .0299 and P = .0128, respectively). Twelve AMR patients had 30 HLA-DRB1/3/4/5 and 32 HLA-DQA/B mismatches. In both HLA-DR and -DQ, de novo DSAs developed against HLAs in association with a greater number of eplet mismatches (P = .0046 and P = .0044, respectively). CONCLUSION: Class II HLA eplet mismatch is a risk factor for de novo DSA and AMR in kidney transplantation recipients. Furthermore, the number of HLA class II eplet mismatches has greater significance as a risk factor than the number of conventional HLA class II mismatches.


Asunto(s)
Rechazo de Injerto/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Trasplante de Riñón , Adulto , Anticuerpos/inmunología , Epítopos/inmunología , Femenino , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Donantes de Tejidos
13.
Transplant Proc ; 50(8): 2581-2582, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30316403

RESUMEN

Living kidney donor guidelines recommend that donors in whom a malignancy is diagnosed should be excluded. Although preoperative screening for malignancies was performed, we experienced a case of living donor with small lymphocytic lymphoma (SLL) at the time of donation. A 53-year-old woman was referred to our hospital for a kidney donation to her son. She had no past medical history of malignancy. We screened the patient using medical examinations, but there was no obvious presence of malignancy. Although preoperative computed tomography showed a small lymph node swelling at the left renal hilum, we diagnosed it as an insignificant lymph node. When a laparoscopic donor nephrectomy was performed, however, we recognized the small lymph node during the surgery and performed a lymphadenectomy. Postoperatively, pathologic examination showed that the small node was lymphocytic lymphoma, known as a low malignant potential disease. Currently, there is no presence of malignancy transmission with the recipient. To the best of our knowledge, this is the first case report of living kidney donor with SLL. Although SLL is considered a low-grade malignancy, it is crucial to follow it carefully in both the donor and the recipient.


Asunto(s)
Trasplante de Riñón/métodos , Leucemia Linfocítica Crónica de Células B , Donadores Vivos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
14.
Phys Rev Lett ; 120(13): 132505, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694189

RESUMEN

We report on the first observation of γ rays emitted from an sd-shell hypernucleus, _{Λ}^{19}F. The energy spacing between the ground state doublet, 1/2^{+} and 3/2^{+} states, of _{Λ}^{19}F is determined to be 315.5±0.4(stat)_{-0.5}^{+0.6}(syst) keV by measuring the γ-ray energy of the M1(3/2^{+}→1/2^{+}) transition. In addition, three γ-ray peaks are observed and assigned as E2(5/2^{+}→1/2^{+}), E1(1/2^{-}→1/2^{+}), and E1(1/2^{-}→3/2^{+}) transitions. The excitation energies of the 5/2^{+} and 1/2^{-} states are determined to be 895.2±0.3(stat)±0.5(syst) and 1265.6±1.2(stat)_{-0.5}^{+0.7}(syst) keV, respectively. It is found that the ground state doublet spacing is well described by theoretical models based on existing s- and p-shell hypernuclear data.

16.
Scand J Surg ; 107(3): 218-223, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29268666

RESUMEN

BACKGROUND AND AIMS: Although some studies have reported the safety of early oral intake after gastrectomy, it still remains controversial. This study focused on the feasibility of a clinical pathway with early oral intake and discharge setting for exclusively laparoscopic distal gastrectomy. MATERIALS AND METHODS: A clinical pathway was applied to 403 patients until December 2014. In the protocol, patients are allowed to take a sip of water and a soft diet on the first and second days after the operation, respectively, and the discharge day is set as the fifth to seventh day after the operation. Clinicopathological variables were prospectively collected, and risk factors for discharge variances were analyzed. RESULTS: The completion rate of the clinical pathway was 76.9%. There were five re-admissions (1.2%). The overall morbidity rate was 18% ( n = 72), and major complications (Clavien-Dindo IIIa or greater) occurred in 13 patients (3%). Complications were the causes for discharge variances in 68 cases (73%), while the attending surgeons' judgment was the cause in 25 cases (27%). On multivariate analysis, age (odds ratio = 2.23, 95% confidence interval = 1.38-3.60, p = 0.001) and operative time (odds ratio = 2.38, 95% confidence interval = 1.45-3.98, p = 0.001) were independent risk factors for discharge variances. CONCLUSION: A high completion rate of a clinical pathway with early oral intake and discharge setting for laparoscopic distal gastrectomy was achievable with an acceptably low re-admission rate. Laparoscopic distal gastrectomy is recommended as a first step for a clinical pathway with an early oral intake and discharge protocol.


Asunto(s)
Vías Clínicas , Gastrectomía , Neoplasias Gástricas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Ingestión de Alimentos , Estudios de Factibilidad , Femenino , Humanos , Laparoscopía , Masculino , Persona de Mediana Edad , Alta del Paciente , Cuidados Posoperatorios
17.
J Chem Phys ; 147(10): 104304, 2017 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-28915746

RESUMEN

The single, double, and triple Auger decays from the 1s shake-up states of O2 have been studied using a multi-electron coincidence method. Efficient populations of two-hole final states are observed in single Auger decays of the π-π* shake-up states, which is understood as a characteristic property of the Auger transitions from shake-up states of an open-shell molecule. The O23+ populations formed by double Auger decays show similar profiles for both the O1s-1 and shake-up states, which is due to the contributions from cascade double Auger processes. While the cascade contributions to the double Auger decays increase with the initial shake-up energy, the probability of direct double Auger processes remains unchanged between the O1s-1 and shake-up states, which implies a weak influence of the excited electron on the double Auger emission that originates from the electron correlation effect.

19.
Clin Pharmacol Ther ; 101(6): 754-762, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27859025

RESUMEN

Drugs under development can cause unpredicted toxicity in humans due to differential drug responsiveness between humans and other disease models, resulting in clinical trial failures. Human induced pluripotent stem cells (iPSCs) are expected to represent a useful tool for toxicity testing. However, among many assays, appropriate cellular assays for predicting neurotoxicity in an iPSC-based model are still uncertain. Here we generated neurons from iPSCs of Charcot-Marie-Tooth disease (CMT) patients. Some CMT patients are sensitive to anticancer drugs and present with an adverse reaction of neuropathy. We analyzed cellular phenotypes and found that mitochondria in neurites of CMT neurons were morphologically shorter and showed slower mobility compared to control. A neurosphere assay showed that treatment with drugs known to cause neuropathy caused mitochondrial aggregations in neurites with adenosine triphosphate shortage in both CMT and control neurons, although more severely in CMT. These findings suggest that the genetically susceptible model could provide a useful tool to predict drug-induced neurotoxicity.


Asunto(s)
Antineoplásicos Fitogénicos/toxicidad , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Modelos Biológicos , Células-Madre Neurales/efectos de los fármacos , Síndromes de Neurotoxicidad/etiología , Toxicología/métodos , Vincristina/toxicidad , Adenosina Trifosfato/metabolismo , Estudios de Casos y Controles , Células Cultivadas , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/metabolismo , Enfermedad de Charcot-Marie-Tooth/patología , Predisposición Genética a la Enfermedad , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Neurogénesis , Síndromes de Neurotoxicidad/genética , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Fenotipo , Medición de Riesgo , Esferoides Celulares
20.
Br J Cancer ; 115(3): 354-63, 2016 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-27310702

RESUMEN

BACKGROUND: Previous studies have revealed that miR-26a-5p and miR-26b-5p act as tumour suppressors in various types of cancer tissues. Here, we aimed to investigate the functional roles of these miRNAs and to identify their regulatory targets in bladder cancer (BC). METHODS: We performed functional assays in BC cells using transfection of mature microRNAs (miRNAs). In silico and luciferase reporter analyses were applied to identify target genes of these miRNAs. The overall survival (OS) of patients with BC was evaluated by the Kaplan-Meier method. RESULTS: miR-26a-5p and miR-26b-5p were significantly downregulated in BC tissues. Restoration of these miRNAs inhibited cell migration and invasion in BC. The gene encoding procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2), a collagen crosslinking enzyme, was directly regulated by miR-26a-5p and miR-26b-5p. Kaplan-Meier analysis revealed that patients with high PLOD2 expression had significantly shorter OS compared with those with low PLOD2 expression (P=0.0153). CONCLUSIONS: PLOD2, which is associated with the stiffness of the extracellular matrix, was directly regulated by miR-26a-5p and miR-26b-5p and may be a good prognostic marker in patients with BC.


Asunto(s)
Genes Supresores de Tumor , MicroARNs/genética , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/genética , Neoplasias de la Vejiga Urinaria/patología , Línea Celular Tumoral , Proliferación Celular , Técnicas de Silenciamiento del Gen , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias de la Vejiga Urinaria/genética
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