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1.
Front Plant Sci ; 14: 1257730, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023841

RESUMO

At present, establishing planted forests, typically composed of not more than two tree species, to avoid forest losses has received increasing attention. In addition, investigating the impact of environmental stress such as waterlogging on different planting patterns is essential for improving wetland ecosystem resilience. Knowledge about the impact of waterlogging on planted forests is crucial for developing strategies to mitigate its adverse effects. Here, we conducted experimentally a simulated pure and mixed planting system composed of two contrasting WL-tolerant species (Cleistocalyx operculatus and Syzygium cumini) to determine their ecophysiological responses based on the type of interaction. Results showed that the aboveground growth performance of S. cumini was better than that of C. operculatus under well-watered conditions regardless of the planting model, which is contrary to the belowground accumulation that was significantly improved in C. operculatus. Intra- and interspecific interactions in different planting models facilitated the growth performance of C. operculatus while provoking a significant competition in S. cumini under waterlogging. Such phenomenon was explained through the remarkable ability of C. operculatus to naturally increase its root network under stress on non-stress conditions compared with S. cumini. In this study, two main factors are proposed to play key roles in the remarkable performance of C. operculatus compared with S. cumini following the planting model under waterlogging. The high level of nitrogen and phosphor absorption through C. operculatus primary roots and the significant starch biosynthesis constituted the key element that characterized the facilitation or competition within the intra- or interspecific interactions shown in C. operculatus compared with S. cumini. Furthermore, the intraspecific competition is more pronounced in S. cumini than in C. operculatus when grown in a pure planting pattern, particularly when subjected to waterlogging. However, when the two species are planted together, this competition is alleviated, resulting in enhanced waterlogging tolerance.

2.
Tree Physiol ; 43(3): 390-403, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36300499

RESUMO

Although environmental factors affecting adventitious root (AR) formation have been examined, how nutrient status affects ARs under waterlogging conditions remains unclear. In this study, plants' performance in responding to AR regulation based on nutrient supply was investigated in terms of plant morphology, physiology and AR traits. Results indicated that Cleistocalyx operculatus possesses higher waterlogging tolerance than Syzygium cumini according to the waterlogging tolerance coefficient, mainly because of the higher fresh weight, porosity and length of AR in C. operculatus. Nutrient supply treatment under a waterlogging condition significantly decreased the fresh weight, length, number, porosity, cortex area of AR and the ratio of cortex-to-stele area in both species relative to those in the waterlogging treatment, but significantly increased the activities and stele areas of AR, and leaf nutrient content. This result showed that nutrient supply caused variations in the morphological and anatomical structures of AR that were more beneficial to improve nutrient transportation than oxygen absorption under waterlogging conditions, supporting the nutrient-priority hypothesis. Moreover, nutrient supply under waterlogging conditions induced greater increase in stele area of ARs, fresh weight of the whole plant, total leaf area, leaf nitrogen level, total chlorophyll content, net photosynthesis rate and maximum photochemical quantum yield of PSII in S. cumini than in C. operculatus, suggesting that S. cumini can transport more nutrients and easily adapts to increase in nutrient supply under waterlogging conditions. Thus, S. cumini have better performance in extracting and utilizing nutrients in the water for plant growth. The findings showed that terrestrial arbor plants have physiological and microstructural mechanisms that respond to nutrient supply under waterlogging conditions and provide novel insights into the phytoremediation of eutrophic water bodies in wetland systems.


Assuntos
Clorofila , Fotossíntese , Água/fisiologia , Nutrientes , Raízes de Plantas/fisiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-36498362

RESUMO

Background: Despite known association of internet addiction with a reduced brain volume and abnormal connectivity, the impact of excessive smartphone use remains unclear. Methods: PubMed, Embase, ClinicalTrial.gov, and Web of Science databases were systematically searched from inception to July 2022 using appropriate keywords for observational studies comparing differences in brain volumes and activations between excessive smartphone users and individuals with regular use by magnetic resonance imaging. Results: Of the 11 eligible studies retrieved from 6993 articles initially screened, seven and six evaluated brain volumes and activations, respectively. The former enrolled 421 participants (165 excessive smartphone users vs. 256 controls), while the latter recruited 276 subjects with 139 excessive smartphone users. The results demonstrated a smaller brain volume in excessive smartphone users compared to the controls (g = −0.55, p < 0.001), especially in subcortical regions (p < 0.001). Besides, the impact was more pronounced in adolescents than in adults (p < 0.001). Regression analysis revealed a significant positive association between impulsivity and volume reduction. Regarding altered activations, the convergences of foci in the declive of the posterior lobe of cerebellum, the lingual gyrus, and the middle frontal gyrus were noted. Conclusions: Our findings demonstrated a potential association of excessive smartphone use with a reduced brain volume and altered activations.


Assuntos
Imageamento por Ressonância Magnética , Smartphone , Adulto , Adolescente , Humanos , Comportamento Impulsivo
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-825028

RESUMO

Objective@# To investigate the diagnosis and treatment of synchronous double primary malignant tumours of the tongue and lung.@*Methods@#A case of adenoid cystic carcinoma(ACC) and lung adenocarcinoma with double primary malignancy was retrospectively analyzed.@*Results@#The tumor of patient′s tongue base gradually grew. MRI showed multiple enlarged lymph nodes on both sides of neck. CT of the chest showed obvious lesions in the anterior basal segment of the right lower lobe. The pathological biopsy of the tongue mass identified ACC, and pathological biopsy of the lung mass identified lung adenocarcinoma. The tongue and lung tumors were both surgically resected, and the tongue defect was repaired at the same time. No residue was found after surgery, and no recurrence was found during the follow-up period. The aesthetic and functional restoration of the lingual region was good.@*Conclusion@#There are few cases of adenoid cystic carcinoma and lung adenocarcinoma with double primary malignancies, and the related diagnosis and treatment are very difficult; the simultaneous removal of double primary malignant tumors may achieve good prognosis.

5.
Ann Surg Oncol ; 25(5): 1237-1244, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29417404

RESUMO

BACKGROUND: Defining the status of solitary pulmonary lesion (SPL) in patients with history of malignancy is important because primary lung cancer (PLC) or intrapulmonary metastasis might indicate different surgical strategies. The aim of this study is to identify factors related to the status of these lesions and construct a clinical model to estimate the pretest probability of PLC. METHODS: From January 2005 to January 2016, 104 patients with previous malignancy and suitable for surgery were retrospectively studied. Univariate and multivariate analyses were performed to identify possible factors related to SPLs. A nomogram was constructed to differentiate PLC from intrapulmonary metastasis. RESULTS: Ninety-seven (93.3%) patients were diagnosed as malignant postoperatively, including 61 patients with intrapulmonary metastasis and 36 patients with PLC. Multivariate analysis showed that site of primary tumor [head and neck squamous cell cancer: odds ratio (OR) = 28.509, P = 0.006; genitourinary cancer: OR = 23.928, P = 0.012], negative lymph node status of primary tumor (OR = 3.154, P = 0.038), spiculation of SPL (OR = 3.972, P = 0.022), and central location of SPL (OR = 4.679, P = 0.026) were four independent factors differentiating PLC from intrapulmonary metastasis. All of these were included in the nomogram. The C-index of the nomogram for predicting probability was 0.82. CONCLUSIONS: Incidence of malignant SPLs was fairly high in patients with history of malignancy. A nomogram including site and lymph node status of primary tumor, and spiculation and location of SPL might be a good tool for differentiating PLC from intrapulmonary metastasis preoperatively and guiding treatment.


Assuntos
Carcinoma de Células Escamosas/secundário , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Pulmonares/secundário , Nomogramas , Nódulo Pulmonar Solitário/patologia , Neoplasias Urogenitais/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico , Adulto Jovem
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