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1.
New Phytol ; 243(2): 607-619, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38764134

RESUMO

Leaf phenology variations within plant communities shape community assemblages and influence ecosystem properties and services. However, questions remain regarding quantification, drivers, and productivity impacts of intra-site leaf phenological diversity. With a 50-ha subtropical forest plot in China's Heishiding Provincial Nature Reserve (part of the global ForestGEO network) as a testbed, we gathered a unique dataset combining ground-derived abiotic (topography, soil) and biotic (taxonomic diversity, functional diversity, functional traits) factors. We investigated drivers underlying leaf phenological diversity extracted from high-resolution PlanetScope data, and its influence on aboveground biomass (AGB) using structural equation modeling (SEM). Our results reveal considerable fine-scale leaf phenological diversity across the subtropical forest landscape. This diversity is directly and indirectly influenced by abiotic and biotic factors (e.g. slope, soil, traits, taxonomic diversity; r2 = 0.43). While a notable bivariate relationship between AGB and leaf phenological diversity was identified (r = -0.24, P < 0.05), this relationship did not hold in SEM analysis after considering interactions with other biotic and abiotic factors (P > 0.05). These findings unveil the underlying mechanism regulating intra-site leaf phenological diversity. While leaf phenology is known to be associated with ecosystem properties, our findings confirm that AGB is primarily influenced by functional trait composition and taxonomic diversity rather than leaf phenological diversity.


Assuntos
Biodiversidade , Florestas , Folhas de Planta , Clima Tropical , Folhas de Planta/fisiologia , Biomassa , Solo , China
2.
Soft Matter ; 20(12): 2767-2776, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38441577

RESUMO

Magnetic nanomaterials are gaining interest for their many applications in technological areas from information science and computing to next-generation quantum energy materials. While magnetic materials have historically been nanostructured through techniques such as lithography and molecular beam epitaxy, there has recently been growing interest in using soft matter self-assembly. In this work, a triblock terpolymer, poly(isoprene-block-styrene-block-ethylene oxide) (ISO), is used as a structure directing agent for aluminosilicate sol nanoparticles and magnetic material precursors to generate organic-inorganic bulk hybrid films with co-continuous morphology. After thermal processing into mesoporous materials, results from a combination of small angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) are consistent with the double gyroid morphology. Nitrogen sorption measurements reveal a type IV isotherm with H1 hysteresis, and yield a specific surface area of around 200 m2 g-1 and an average pore size of 23 nm. The magnetization of the mesostructured material as a function of applied field shows magnetic hysteresis and coercivity at 300 K and 10 K. Comparison of magnetic measurements between the mesoporous gyroid and an unstructured bulk magnetic material, derived from the identical inorganic precursors, reveals the structured material exhibits a coercivity of 250 Oe, opposed to 148 Oe for the unstructured at 10 K, and presence of remnant magnetic moment not conventionally found in bulk hematite; both of these properties are attributed to the mesostructure. This scalable route to mesoporous magnetic materials with co-continuous morphologies from block copolymer self-assembly may provide a pathway to advanced magnetic nanomaterials with a range of potential applications.

3.
Pediatr Surg Int ; 40(1): 191, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012349

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a life-threatening disease that affects premature infants. However, the role of inflammatory biomarkers in identifying surgical/death NEC without pneumoperitoneum remains elusive. PURPOSE: We aimed to verify the value of platelet-to-lymphocyte ratio (PLR) and the combination of white blood cell (WBC), absolute neutrophil count (ANC), absolute lymphocyte count (ALC), neutrophil lymphocyte ratio (NLR), PLR, C reactive protein (CRP) and procalcitonin (PCT) in predicting the severity of NEC, and to construct a model to differ surgically NEC from non-surgically NEC. METHODS: A retrospective analysis was performed on 191 premature infants with NEC. Based on the inclusion and exclusion criteria, 90 infants with Stage II and IIIA NEC were enrolled in this study, including surgical/death NEC (n = 38) and medical NEC (n = 52). The values of inflammatory biomarkers were collected within 24 h of onset. RESULTS: The univariate analysis revealed that the values of WBC (p = 0.040), ANC (p = 0.048), PLR (p = 0.009), CRP (p = 0.016) and PCT (p < 0.01) in surgical/death NEC cohort were significantly higher than medical NEC cohort. Binary multivariate logistic regression analysis indicates that ANC, PLR, CRP, and PCT are capable of distinguishing infants with surgical/death NEC, and the AUC of the regression equation was 0.79 (95% CI 0.64-0.89; sensitivity 0.63; specificity 0.88), suggesting the equation has a good discrimination. IMPLICATIONS FOR PRACTICE AND RESEARCH: Elevated PLR is associated with severe inflammation in surgical/death NEC patients. The prediction modelling of combination of ANC, PLR, CRP and PCT can differentiate surgical/death NEC from infants with medical NEC, which may improve risk awareness and facilitate effective communication between nurses and clinicians. However, multicentre research is needed to verify these findings for better clinical management of NEC.


Assuntos
Biomarcadores , Proteína C-Reativa , Enterocolite Necrosante , Recém-Nascido Prematuro , Humanos , Enterocolite Necrosante/cirurgia , Enterocolite Necrosante/sangue , Enterocolite Necrosante/diagnóstico , Estudos Retrospectivos , Recém-Nascido , Biomarcadores/sangue , Masculino , Feminino , Proteína C-Reativa/análise , Pró-Calcitonina/sangue , Pneumoperitônio/sangue , Inflamação/sangue , Contagem de Leucócitos , Doenças do Prematuro/cirurgia , Doenças do Prematuro/sangue , Doenças do Prematuro/diagnóstico
4.
Angew Chem Int Ed Engl ; : e202408309, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39104033

RESUMO

Advancing the energy-intensive Haber-Bosch process faces significant challenges due to the intrinsic constraints of scaling relations in heterogeneous catalysis. Herein, we reported an approach of bending the "seesaw effect" to regulate the scaling relations over a tailored α-Fe metallic material (α-Fe-110s), realizing highly efficient light-driven thermal catalytic ammonia synthesis rate of 1260 µmol gcatalyst-1 h-1 without additional heating. Specifically, the thermal catalytic activity of α-Fe-110s was significantly enhanced by the novel stepped {110} surface, exhibiting a 3.8-fold increase compared to the commercial fused-iron catalyst with promoters at 350 °C. The photo-induced hot electron transfer further accelerates the dinitrogen dissociation and hydrogenation simultaneously, effectively overcoming the limitation of scaling relation over identical sites. Consequently, the ammonia production rate of α-Fe-110s was further enhanced by 30 times at the same temperature with irradiation. This work designs an efficient and sustainable system for ammonia synthesis and provides a novel approach for regulating the scaling relations in heterogeneous catalysis.

5.
Sensors (Basel) ; 23(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37420596

RESUMO

Optical fiber sensors are newly established gas pipeline leakage monitoring technologies with advantages, including high detection sensitivity to weak leaks and suitability for harsh environments. This work presents a systematic numerical study on the multi-physics propagation and coupling process of the leakage-included stress wave to the fiber under test (FUT) through the soil layer. The results indicate that the transmitted pressure amplitude (hence the axial stress acted on FUT) and the frequency response of the transient strain signal strongly depends on the types of soil. Furthermore, it is found that soil with a higher viscous resistance is more favorable to the propagation of spherical stress waves, allowing FUT to be installed at a longer distance from the pipeline, given the sensor detection limit. By setting the detection limit of the distributed acoustic sensor to 1 nε, the feasible range between FUT and the pipeline for clay, loamy soil and silty sand is numerically determined. The gas-leakage-included temperature variation by the Joule-Thomson effect is also analyzed. Results provide a quantitative criterion on the installation condition of distributed fiber sensors buried in soil for the great-demanding gas pipeline leakage monitoring applications.


Assuntos
Fibras Ópticas , Solo , Física , Argila , Acústica
6.
BMC Cardiovasc Disord ; 22(1): 468, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335294

RESUMO

BACKGROUND: Although catheter ablation (CA) is an effective treatment for non-valvular atrial fibrillation (AF), a good many of patients still have a recurrence following post-operation. Prediction of AF recurrence by evaluating left atrial (LA) phase function with speckle tracking echocardiography (STE) may be helpful for risk stratification and clinical management for AF patients. Therefore, the current study aimed to assess the prognostic value of LA strains in non-valvular AF patients after CA. METHODS: A total of 95 non-valvular AF patients (70.5% paroxysmal AF, 56.8% males, mean age 63.2 ± 9.7 years) were included in this retrospective study between October 2019 and August 2020. Transthoracic echocardiography was performed in all the subjects and STE was used to analyze the LA reservoir strain (LASr), LA conduit strain (LAScd) and LA contractile strain (LASct) during different phases before CA. Patients were followed up with until January 2022. The endpoint was AF recurrence. RESULTS: Over a median follow-up period of 26.0 months (interquartile range, 24.7-26.7 months), 26 patients experienced recurrence and 69 stayed in sinus rhythm. Compared with no-recurrence group, maximum volume of LA (LAVmax), minimum volume of LA (LAVmin) and LA volume index (LAVI) were increased in the recurrence group, while LAEF, LASr and LASct were worsened (P < 0.05). Multivariable logistic regression analysis revealed that LASct was an independent predictor of AF recurrence (odds ratio, 0.89; 95% confidence interval (CI), 0.82-0.97; P = 0.007) and receiver operating characteristic (ROC) curve analysis showed an area under the curve of LASct<8% was 0.70 (95% CI, 0.59-0.79; P = 0.0008). CONCLUSIONS: LASct was of independent predictive value of AF recurrence. LA function assessed by STE may contribute to the risk stratification for AF patients and selection of suitable patients for CA.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Estudos Retrospectivos , Átrios do Coração , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Função do Átrio Esquerdo
7.
BMC Cardiovasc Disord ; 22(1): 134, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361126

RESUMO

INTRODUCTION: Fibrosing mediastinitis (FM) complicated with pulmonary hypertension (PH) has been considered as an important cause of morbidity and mortality. This study was designed to observe the possible effects of abnormal hemodynamics on patients by conducting a between-group comparison according to the presence of markedly increased systolic pulmonary arterial pressure (SPAP), so as to provide more information for clinical management. MATERIALS AND METHODS: Fifty-one patients with clinically diagnosed FM were divided in two groups (SPAP < 50 mmHg group; SPAP ≥ 50 mmHg group) and retrospectively included in the study. Data mainly including demographic factors, echocardiographic data, results of right heart catheter and computed tomography (CT) examination were retrieved from the medical database. Echocardiographic parameters pre- and post- balloon pulmonary angioplasty (BPA) treatment were also collected in 8 patients. RESULTS: Significant changes in cardiac structure, hemodynamics and cardiac function were detected in patients complicated with markedly increased SPAP. Patients in the SPAP ≥ 50 mmHg group had increased right heart diameter, right heart ratio and velocity of tricuspid regurgitation (VTR) (p < 0.05). Deteriorated right heart function was also observed. There was no significant difference in CT findings between the two groups, except that more patients in the SPAP ≥ 50 mmHg group had pleural effusion (p < 0.05). After primary BPA in 8 patients, improvement in the right atrium proportion was observed. CONCLUSIONS: Changes due to significantly increased SPAP in patients with FM include adverse structure and function of the right heart, but differences in CT findings were not significant. Echocardiography has advantages as a noninvasive tool for the evaluation of cardiac structure, function and hemodynamics in patients with FM.


Assuntos
Pressão Arterial , Mediastinite , Humanos , Mediastinite/diagnóstico por imagem , Mediastinite/terapia , Estudos Retrospectivos , Esclerose , Sístole
8.
Clin J Sport Med ; 32(4): 400-407, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34342297

RESUMO

OBJECTIVE: To examine the factor structure of the Sport Concussion Assessment Tool-5 (SCAT5) symptom scale in adolescents on their initial presentation to a concussion clinic within the typical recovery period after concussion (ie, <30 days). We hypothesize that the SCAT5 symptoms represent various clinically meaningful groups. A secondary purpose was to examine the effects of sex on the factor structure of the SCAT5 symptom scale. STUDY DESIGN: Retrospective cross-sectional analysis. SETTING: Tertiary, institutional. PATIENTS: Nine hundred eighty-one adolescents (45% women) aged between 13 and 18 years. INDEPENDENT VARIABLES: Adolescents completed the SCAT5 symptom scale. MAIN OUTCOME MEASURES: The factor structure of SCAT5 examined using a principal axis factor analysis. RESULTS: A 5-factor structure model explained 61% of the variance in symptoms. These 5 factors are identified as Energy (17%), Mental Health (13%), Migrainous (13%), Cognitive (9%), and Vestibulo-Ocular (9%). A similar 5-factor model emerged for each sex, and the proportion of variance in symptoms explained by the 5-factor model was comparable between the sexes. CONCLUSIONS: The findings of this report indicate that the SCAT5 symptoms aggregated into 5 delineated factors, and these factors were largely consistent across the sexes. The delineation of symptoms into 5 factors provides preliminary validation for the presence of different concussion phenotypes. Confirmatory factor analysis is warranted to examine the applicability and clinical utility of the use of the 5-factor structure in a clinical setting.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Adolescente , Traumatismos em Atletas/complicações , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico , Estudos Transversais , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos
9.
New Phytol ; 229(3): 1388-1397, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33073860

RESUMO

That functional traits should affect individual performance and, in turn, determine fitness and population growth, is a foundational assumption of trait-based ecology. This assumption is, however, not supported by a strong empirical base. Here, we measured simultaneously two individual performance metrics (survival and growth), seven traits and 10 environmental properties for each of 3981 individuals of 205 species in a 50-ha stem-mapped subtropical forest. We then modelled survival/growth as a function of traits, environments and trait × environment interactions, and quantified their relative importance at both the species and individual levels. We found evidence of alternative functional designs and multiple performance peaks along environmental gradients, indicating the presence of complicated trait × environment interactions. However, such interactions were relatively unimportant in our site, which had relatively low environmental variations. Moreover, individual performance was not better predicted, and trait × environment interactions were not more likely detected, at the individual level than at the species level. Although the trait × environment interactions might be safely ignored in relatively homogeneous environments, we encourage future studies to test the interactive effects of traits and environments on individual performances and lifelong fitness at larger spatial scales or along experimentally manipulated environmental gradients.


Assuntos
Ecologia , Florestas , Fenótipo
10.
New Phytol ; 229(2): 1078-1090, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32924174

RESUMO

Environmental filtering and limiting similarity mechanisms can simultaneously structure community assemblages. However, how they shape the functional and phylogenetic structure of root neighborhoods remains unclear, hindering the understanding of belowground community assembly processes and diversity maintenance. In a 50-ha plot in a subtropical forest, China, we randomly sampled > 2700 root clusters from 625 soil samples. Focusing on 10 root functional traits measured on 76 woody species, we examined the functional and phylogenetic structure of root neighborhoods and linked their distributions with environmental cues. Functional overdispersion was pervasive among individual root traits (50% of the traits) and accentuated when different traits were combined. Functional clustering (20% of the traits) seemed to be associated with a soil nutrient gradient with thick roots dominating fertile areas whereas thin roots dominated infertile soils. Nevertheless, such traits also were sorted along other environmental cues, showing multidimensional adaptive trait syndromes. Species relatedness also was an important factor defining root neighborhoods, resulting in significant phylogenetic overdispersion. These results suggest that limiting similarity may drive niche differentiation of coexisting species to reduce competition, and that alternative root strategies could be crucial in promoting root neighborhood resource use and species coexistence.


Assuntos
Florestas , Solo , China , Filogenia , Madeira
11.
Bioorg Med Chem Lett ; 47: 128230, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34186178

RESUMO

A series of novel ligustrazine-chalcone hybrids were synthesized and evaluated for their in vitro and in vivo antitumor activities. The results showed that most of these compounds exhibited significant in vitro cytotoxicity against MDA-MB-231, MCF-7, A549 and HepG2 cell lines with IC50 values as low as sub-micromole. Among them, compounds 6c and 6f possessed better comprehensive characteristics for the antiproliferation effects on both MDA-MB-231 (IC50: 6c, 1.60 ± 0.21 µM; 6f, 1.67 ± 1.25 µM) and MCF-7 (IC50: 6c, 1.41 ± 0.23 µM; 6f, 1.54 ± 0.30 µM). They also exhibited the potent colony-formation inhibitory abilities on above two cell lines in both concentration and time dependent manners, as well as the significantly suppression capabilities against the migration of such cell lines in a concentration dependent manner by wound-healing assay. Of note, compound 6c could significantly induce the apoptosis of MDA-MB-231 cells in a concentration dependent manner and inhibited the transformation of the growth cycle of MDA-MB-231 cells and blocked the cell growth cycle in G0/G1 phase. Moreover, the in vivo antiproliferation assay of compound 6c on TNBC model indicated such compound had a remarkable potency against tumor growth with a widely safety window. Further immunohistochemistry analysis illustrated that compound 6c was provided with a potent capacity to significantly reduce the Ki-67 positive rate in a dose dependent manner. All the results suggested that these hybrids presented both in vitro and in vivo proliferation inhibition potency against breast cancer and further development with good therapeutic potential should be of great interest.


Assuntos
Antineoplásicos/farmacologia , Chalcona/farmacologia , Pirazinas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalcona/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Pirazinas/química , Relação Estrutura-Atividade , Neoplasias de Mama Triplo Negativas/patologia
12.
Tohoku J Exp Med ; 254(4): 275-282, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34433731

RESUMO

Nephrotoxicity occasionally occurs during treatment with immune checkpoint inhibitors (ICIs). Few related studies compare the differences between these drugs. This study aimed to systematically characterize nephrotoxicity after ICI initiation. Data were extracted from the US FDA Adverse Event Reporting System (FAERS) database. Disproportionality analysis, including information components (ICs) and reporting odds ratios (RORs), was performed to determine the potential renal toxicity of ICIs. A total of 7,204 reports of renal adverse events (AEs) were identified in the FAERS database. Renal AEs were most commonly reported for nivolumab (46.84%). Strong signals were detected in male patients combined with ICIs. In the clinical application of ICIs, attention should be paid to patients, especially male patients, with acute kidney injury, nephritis, autoimmune nephritis and other nephrotoxic AEs. The use of ICIs is likely to aggravate their condition.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Inibidores de Checkpoint Imunológico , Humanos , Masculino , Nivolumabe/efeitos adversos , Farmacovigilância , Estados Unidos/epidemiologia , United States Food and Drug Administration
13.
BMC Neurol ; 20(1): 289, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736532

RESUMO

BACKGROUND: To evaluate the medium-and long-term effect of intravascular interventional therapy for symptomatic severe basilar artery stenosis supported by multimodal imaging. METHOD: After strict screening of 67 patients with symptomatic severe basilar artery stenosis (70-99%) with atherosclerotic stenosis, 67 patients with symptomatic recurrence after intensive drug treatment were treated with intravascular balloon dilatation and Enterprise stent implantation. Any stroke or death within 30 days after operation and any stroke and restenosis during medium-and long-term follow-up were recorded. RESULTS: ①The mean age of 67 patients (67lesions) was 57 ± 8 years old, and the technical success rate was 100%; ②Preoperative angiography showed that the collateral circulation was poor, and TICI was 1-2a while postoperative angiography showed that TICI was significantly improved to 2b-3; ③The average preoperative stenosis rate was 82 ± 9%, and the postoperative stenosis rate was reduced to 17 ± 10%; ④Before surgery, abnormal perfusion was found in the posterior circulation CTP; After the postoperative re-examination, the posterior circulation of CTP perfusion was significantly improved; ⑤Postoperative symptoms and neurological conditions improved significantly; ⑥Complications of perforating branch event occurred in 1 case after operation, and symptoms were relieved after more than 1 month of medication treatment, and mild neurological dysfunction remained. 1 case developed subacute thrombosis in the stent, which improved after active intra-arterial thrombolysis, and there was no residual neurological dysfunction; and 1 case of micro-guide wire being trapped by the distal vasospasm. ⑦67 patients were followed up by telephone, WeChat or imaging for 36-66 months. CONCLUSIONS: In summary intravascular balloon dilation + Enterprise stent implantation is safe and effective for the treatment of symptomatic severe atherosclerotic stenosis of the basilar artery, with high technical success rate, low perioperative complications, and good mid-term and long-term effects.


Assuntos
Aterosclerose/complicações , Artéria Basilar/diagnóstico por imagem , Procedimentos Endovasculares/métodos , Insuficiência Vertebrobasilar/diagnóstico por imagem , Idoso , Circulação Colateral , Constrição Patológica/diagnóstico por imagem , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Complicações Pós-Operatórias/epidemiologia , Stents , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
14.
Ann Bot ; 124(5): 861-867, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31420646

RESUMO

BACKGROUND AND AIMS: The patterns of niche occupation in functional trait space have been widely studied to understand the processes of community assembly, but are rarely linked to environmental conditions (here, stress and disturbance). In this study, we investigate (1) how the pattern of functional niche occupation, incorporating intraspecific trait variation and covariation, varies along experimental gradients of stress and disturbance, (2) whether habitat filtering and/or limiting similarity modify the pattern, and (3) whether their strength varies as a function of species richness or levels of stress and disturbance. METHODS: We constructed an experimental system consisting of 24 herbaceous plant mesocosms under different levels of stress and disturbance, and measured ten traits on five individuals for each species in each mesocosm. We quantified the total functional niche volume occupied by an entire mesocosm, the functional niche overlap among species within a mesocosm and the average functional niche volume occupied per species, and investigated how these metrics varied from species-poor to species-rich mesocosms along gradients of stress and disturbance. KEY RESULTS: Species richness and functional niche overlap correlated positively to disturbance at low and medium levels of stress, but peaked at the intermediate level of disturbance when stress was high. The total functional niche volume and average functional niche volume did not change significantly along these gradients. Compared to null models, each mesocosm occupied a smaller total functional niche volume (habitat filtering) and the species within each mesocosm overlapped less and were more functionally specialized (limiting similarity). Moreover, the standardized metrics (to the null expectations) did not change significantly under different levels of stress and disturbance. CONCLUSIONS: This experimental evidence shows that both habitat filtering and limiting similarity determine the patterns of functional niche occupation and species richness, but their strength does not change along environmental gradients of stress and disturbance.


Assuntos
Ecossistema , Plantas , Ocupações , Fenótipo
15.
Ecology ; 99(4): 775-781, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29377088

RESUMO

We created 24 mesocosms containing mixtures of herbaceous species arranged along experimentally maintained gradients of stress (external abiotic constraints limiting biomass production) and disturbance (events causing partial or total live biomass destruction) in order to determine the degree to which community assembly is deterministic or historically contingent during succession. In this 7-yr experiment, we found taxonomic divergence and functional convergence during the last 3 yr. Although communities became more functionally dissimilar as the difference in the level of stress increased, they were equally taxonomically different irrespective of the amount of difference between them in terms of stress and disturbance. In addition, comparing communities experiencing the same conditions, taxonomic community structure was more dissimilar as the levels of stress and disturbance decreased. Therefore, community assembly was largely deterministic from a functional perspective but more historically contingent from a taxonomic perspective, and the relative importance of taxonomic historical contingency decreased as the levels of stress and disturbance frequency increased.


Assuntos
Plantas , Biomassa , Ecologia
16.
Luminescence ; 31(1): 38-46, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25920391

RESUMO

Two flavonoids, tectoridin (TD) isolated from rhizomes of Iris tectorum and hydrolyzed aglycone tectorigenin (TG) were prepared and characterized to compare their different interaction ability with human serum albumin (HSA). Based on the results, the affinity of TG-HSA was stronger than that of TD-HAS, and TG combined more closely with HSA than did TD. HSA fluorescence was quenched by TD/TG. The interactions between TD/TG and HSA involved static quenching. The thermodynamic parameters indicated that both binding processes were spontaneous; hydrogen binding and van der Waals force were the main forces between TD and HSA, whereas a hydrophobic interaction was the main binding force between TG and HSA. Synchronous and 3D fluorescence spectra showed that the binding of TD/TG to HSA induced conformational changes. Moreover, a docking study confirmed the experimental results.


Assuntos
Flavonoides/química , Gênero Iris/química , Isoflavonas/química , Simulação de Acoplamento Molecular , Rizoma/química , Albumina Sérica/química , Flavonoides/síntese química , Flavonoides/isolamento & purificação , Humanos , Isoflavonas/isolamento & purificação , Espectrometria de Fluorescência
17.
Ecol Lett ; 18(12): 1406-19, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26415616

RESUMO

Recent studies have shown that accounting for intraspecific trait variation (ITV) may better address major questions in community ecology. However, a general picture of the relative extent of ITV compared to interspecific trait variation in plant communities is still missing. Here, we conducted a meta-analysis of the relative extent of ITV within and among plant communities worldwide, using a data set encompassing 629 communities (plots) and 36 functional traits. Overall, ITV accounted for 25% of the total trait variation within communities and 32% of the total trait variation among communities on average. The relative extent of ITV tended to be greater for whole-plant (e.g. plant height) vs. organ-level traits and for leaf chemical (e.g. leaf N and P concentration) vs. leaf morphological (e.g. leaf area and thickness) traits. The relative amount of ITV decreased with increasing species richness and spatial extent, but did not vary with plant growth form or climate. These results highlight global patterns in the relative importance of ITV in plant communities, providing practical guidelines for when researchers should include ITV in trait-based community and ecosystem studies.


Assuntos
Biodiversidade , Fenótipo , Fenômenos Fisiológicos Vegetais , Especificidade da Espécie
18.
World Allergy Organ J ; 17(4): 100899, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623319

RESUMO

Background: Several observational studies suggest a possible link between lipid-lowering drugs and allergic diseases. However, inferring causality from these studies can be challenging due to issues such as bias, reverse causation, and residual confounding. To investigate the potential causal effect of lipid-lowering drugs, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) inhibitors, on allergic diseases (allergic asthma, allergic conjunctivitis, atopic dermatitis, allergic rhinitis, and allergic urticaria), we performed a Mendelian randomization (MR)-based study. Methods: We employed MR and summary-data-based MR (SMR), analyzing genome-wide association study (GWAS) data from people of European descent. Single nucleotide polymorphisms (SNPs) were employed as instrumental variables. We selected 2 types of genetic measures to represent the impact of lipid-lowering drugs, including genetic variants near or within drug target genes correlated with low-density lipoprotein cholesterol (LDL-C), and expression quantitative trait loci of drug target genes. The inverse-variance weighted (IVW)-MR approach was the primary utilized MR method, while sensitivity analyses were used to test the robustness of the results. We used SMR analysis as a supplementary analytical method, applying the heterogeneity in dependent instruments (HEIDI) test to assess if the observed correlation between gene expression and outcome was due to a linkage situation. Results: The IVW-MR analysis revealed significant evidence for an association between PCSK9-mediated LDL-C reduction and a decrease in the risk of allergic asthma (odds ratio [OR] = 1.31, 95% confidence interval [CI] = 1.11-1.56; P < 0.01). Likewise, SMR analysis discovered an augmented expression of PCSK9 being linked with a heightened susceptibility to allergic asthma (OR = 1.21, 95% CI = 1.03-1.43; P = 0.02). No consistent evidence was found for other associations in either analysis. Conclusion: Our findings support a potential causal relationship between PCSK9 activity and an increased risk of allergic asthma. Thus, PCSK9 inhibitors, which reduce PCSK9 activity, might be considered a priority in future clinical trials investigating drugs for allergic asthma prevention or treatment.

19.
J Med Case Rep ; 18(1): 305, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38926771

RESUMO

BACKGROUND: Testicular metastasis from malignant solid tumors is extremely rare. It is usually found by chance during autopsy or pathological examination of testicular specimens. Therefore, we consider it necessary to report our patient's case of testicular metastasis from colon cancer. CASE PRESENTATION: We report a 61-year-old Han Chinese male patient who presented to our clinic with progressive painless swelling of the right testicle for 2 years. Positron emission tomography-computed tomography scans showed increased 18F-fluorodeoxyglucose metabolism in the right testicle, possibly owing to distant metastasis. His previous medical history suggested that he had undergone laparoscopic-assisted right hemicolectomy for ascending colon cancer 4 years ago. Considering the ascending colon cancer metastasis to the right testicle, we performed a right radical testicular resection through an inguinal approach. Postoperative histological examination showed intestinal metastatic adenocarcinoma. CONCLUSION: Colon cancer metastasis to the testes is uncommon. The clinical and imaging manifestations of this tumor are nonspecific, so the diagnosis relies on postoperative pathology. If testicular metastasis is found, treatment principles for advanced colon cancer should be followed.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Testiculares , Humanos , Masculino , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia , Neoplasias Testiculares/secundário , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Pessoa de Meia-Idade , Adenocarcinoma/secundário , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Colectomia , Orquiectomia , Colo Ascendente/patologia , Fluordesoxiglucose F18
20.
ACS Nano ; 18(29): 19150-19160, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39001859

RESUMO

Soft gels with spatially defined mesoscale distributions of chemical activity that guide and accelerate reactions by chemical nanoconfinement are found ubiquitously in nature but are rare in artificial systems. In this study, we introduce chemically nanostructured bulk organogels with periodically ordered morphologies from self-assembled block copolymer monoliths with a single selectively cross-linked block (xBCP). Ordered bulk organogels are fabricated with various distinct morphologies including hexagonally packed cylinders and two gyroidal three-dimensionally periodic network structures that exhibit macroscopic and nanoscopic structural integrity upon swelling. Small-angle X-ray scattering and transmission electron microscopy confirm that the periodic arrangement of the chemically distinct blocks in the self-assembled xBCP is retained at polymer fractions as low as 15 vol %. Our results reveal that the swelling equilibrium is not exclusively determined by the cross-linked block despite its structural role but is strongly influenced by the weighted interactions between solvent and the individual nanophases, including the non-cross-linked blocks. Therefore, substantial swelling can be obtained even for solvents that the cross-linked block itself has unfavorable interactions with. Since these ordered organogels present a class of solvent-laden bulk materials that exhibit chemically distinct nanoenvironments on a periodic mesoscale lattice, we demonstrate their use for selective infusion templating (SIT) in a proof-of-concept nanoconfined synthesis of poly(acrylonitrile) from which a monolithic ordered gyroidal mesoporous carbon is obtained. Going forward, we envision using xBCP gels and SIT to enable the fabrication of traditionally hard-to-template materials as periodically nanostructured monoliths due to the extensive tunability in their physicochemical parameter space.

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