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1.
J Exp Bot ; 74(1): 162-177, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255986

RESUMO

Rosaceae is an economically important plant family that can be affected by a multitude of pathogenic microbes, some of which can cause dramatic losses in production. As a type of pattern-recognition receptor, receptor-like proteins (RLPs) are considered vital regulators of plant immunity. Based on genome-wide identification, bioinformatic analysis, and functional determination, we investigated the evolutionary characteristics of RLPs, and specifically those that regulate Valsa canker, a devastating fungal disease affecting apple and pear production. A total of 3028 RLPs from the genomes of 19 species, including nine Rosaceae, were divided into 24 subfamilies. Five subfamilies and seven co-expression modules were found to be involved in the responses to Valsa canker signals of the resistant pear rootstock Pyrus betulifolia 'Duli-G03'. Fourteen RLPs were subsequently screened as candidate genes for regulation of resistance. Among these, PbeRP23 (Chr13.g24394) and PbeRP27 (Chr16.g31400) were identified as key resistance genes that rapidly enhance the resistance of 'Duli-G03' and strongly initiate immune responses, and hence they have potential for further functional exploration and breeding applications for resistance to Valsa canker. In addition, as a consequence of this work we have established optimal methods for the classification and screening of disease-resistant RLPs.


Assuntos
Ascomicetos , Malus , Pyrus , Rosaceae , Rosaceae/genética , Rosaceae/metabolismo , Filogenia , Evolução Molecular , Melhoramento Vegetal , Malus/genética , Malus/metabolismo , Pyrus/genética , Pyrus/metabolismo , Ascomicetos/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Exp Biol ; 226(17)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589414

RESUMO

Landing is a critical phase for flying animals, whereby many rely on visual cues to perform controlled touchdown. Foraging honeybees rely on regular landings on flowers to collect food crucial for colony survival and reproduction. Here, we explored how honeybees utilize optical expansion cues to regulate approach flight speed when landing on vertical surfaces. Three sensory-motor control models have been proposed for landings of natural flyers. Landing honeybees maintain a constant optical expansion rate set-point, resulting in a gradual decrease in approach velocity and gentile touchdown. Bumblebees exhibit a similar strategy, but they regularly switch to a new constant optical expansion rate set-point. In contrast, landing birds fly at a constant time to contact to achieve faster landings. Here, we re-examined the landing strategy of honeybees by fitting the three models to individual approach flights of honeybees landing on platforms with varying optical expansion cues. Surprisingly, the landing model identified in bumblebees proved to be the most suitable for these honeybees. This reveals that honeybees adjust their optical expansion rate in a stepwise manner. Bees flying at low optical expansion rates tend to increase their set-point stepwise, while those flying at high optical expansion rates tend to decrease it stepwise. This modular landing control system enables honeybees to land rapidly and reliably under a wide range of initial flight conditions and visual landing platform patterns. The remarkable similarity between the landing strategies of honeybees and bumblebees suggests that this may also be prevalent among other flying insects. Furthermore, these findings hold promising potential for bioinspired guidance systems in flying robots.


Assuntos
Sinais (Psicologia) , Esportes , Abelhas , Animais , Flores , Alimentos , Reprodução
3.
Can J Microbiol ; 69(12): 479-487, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37379574

RESUMO

The surface morphology of mature biofilms is heterogeneous and can be divided into concentric rings wrinkles (I), labyrinthine networks wrinkles (II), radial ridges wrinkles (III), and branches wrinkles (IV), according to surface wrinkle structure and distribution characteristics. Due to the wrinkle structures, channels are formed between the biofilm and substrate and transport nutrients, water, metabolic products, etc. We find that expansion rate variations of biofilms growing on substrates with high and low agar concentrations (1.5, 2.0, 2.5 wt.%) are not in the same phase. In the first 3 days' growth, the interaction stress between biofilm and each agar substrate increases, which makes the biofilm expansion rate decreases before wrinkle pattern IV (branches) comes up. After 3 days, in the later growth stage after wrinkle pattern IV appears, the biofilm has larger expansion rate growing on 2.0 wt.% agar concentration, which has the larger wrinkle distance in wrinkle pattern IV reducing energy consumption. Our study shows that the stiff substrate does not always inhibit the biofilm expansion, although it does in the earlier stage; after that, mature biofilms acquire larger expansion rate by adjusting the growth mode through the wrinkle evolution even in nutrient extremely depletion.


Assuntos
Bacillus subtilis , Biofilmes , Ágar/metabolismo , Bacillus subtilis/metabolismo , Água/metabolismo
4.
Ann Vasc Surg ; 82: 258-264, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34896549

RESUMO

BACKGROUND: Iliac artery aneurysms (IAAs) are life-threatening once ruptured. Although some studies have revealed the pathology of IAAs, clinical information on IAAs is still limited. Moreover, previous studies were conducted in Western countries; thus, we aimed to identify the natural history of iliac artery aneurysms in a Japanese cohort. The purpose of this study was to investigate the IAA expansion rate in a Japanese cohort to consider the management of small IAAs and to identify indications for surgical intervention. METHODS: Patients with iliac artery aneurysms were retrospectively reviewed. The primary outcome was the expansion rate of IAAs. We also investigated the correlation between expansion rate and patients' characteristics. Natural histories, including surgical interventions and rupture, were also assessed. RESULTS: The mean expansion rate in our study was 1.59 ± 1.16 mm/year. There was a positive correlation between expansion rate and aneurysm diameter, which was estimated by y = 0.0052 × (X - 23.270)2 + 0.0632 × X - 0.0517, where y is the expansion rate, and X is aneurysm diameter. The freedom from surgical intervention rate of IAAs was 85.5% at 1 year, 54.0% at 3 years, and 41.5% at 5 years. No factors, except initial aneurysm diameter, were revealed as independent predictors of surgical intervention. We experienced one ruptured IAA, which showed unexpected rapid growth from 30.1 mm to 56.3 mm over 15 months during conservative management. This case demonstrated that IAAs ≥30 mm should be carefully followed up and considered for surgical intervention. CONCLUSIONS: We conclude that larger aneurysms have greater expansion rates. Because IAAs ≥30 mm carry a risk of rapid expansion resulting in rupture, careful follow-up, and surgical intervention should be performed if iliac artery aneurysms are ≥30 mm in diameter.


Assuntos
Implante de Prótese Vascular , Aneurisma Ilíaco , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/etiologia , Aneurisma Ilíaco/cirurgia , Artéria Ilíaca/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
5.
J Exp Bot ; 71(1): 11-21, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31613967

RESUMO

Plant growth is a highly complex biological process that involves innumerable interconnected biochemical and signalling pathways. Many different techniques have been developed to measure growth, unravel the various processes that contribute to plant growth, and understand how a complex interaction between genotype and environment determines the growth phenotype. Despite this complexity, the term 'growth' is often simplified by researchers; depending on the method used for quantification, growth is viewed as an increase in plant or organ size, a change in cell architecture, or an increase in structural biomass. In this review, we summarise the cellular and molecular mechanisms underlying plant growth, highlight state-of-the-art imaging and non-imaging-based techniques to quantitatively measure growth, including a discussion of their advantages and drawbacks, and suggest a terminology for growth rates depending on the type of technique used.


Assuntos
Genótipo , Fenótipo , Desenvolvimento Vegetal , Genômica , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/fisiologia
6.
Dermatol Ther ; 33(6): e14393, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33037725

RESUMO

Meshed skin grafting is a common technique in operations to minimize surgery on the donor site area. However, the donor site area is empirically determined by surgeons due to the lack of a reliable formula to calculate the donor area required to cover a skin defect. To determine the minimal size for donor skin, the expansion rates of 1.5:1, 3:1, and 6:1 meshed skin graft and the area actually covered by them were investigated in real-world operations. About 51 patients who received 57 operations with meshed skin grafts were enrolled in this study. The average clinical coverage rates of area in cases in which 1.5:1, 3:1, or 6:1 meshed skin grafting was performed were 1.02, 1.29, or 2.18, respectively. Those rates were notably low when recipient sites were concave. The average expansion rates of 1.5:1, 3:1, and 6:1 meshed skin grafts were about 1.16, 1.61, and 2.32, respectively. These results indicate that the size of donor skin should be about 85%, 60%, and 45% size of the recipient site to achieve the target 1.5:1, 3:1, and 6:1 meshed skin graft, respectively. In addition, the donor area should be adjusted in consideration of the shape of the recipient sites.


Assuntos
Queimaduras , Transplante de Pele , Humanos , Próteses e Implantes , Pele , Doadores de Tecidos
7.
Dev Growth Differ ; 61(7-8): 431-443, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31565797

RESUMO

Biofilms are communities of tightly associated bacteria encased in an extracellular matrix and attached to surfaces of various objects, such as liquid or solid surfaces. Here we use the multi-channel wide field stereo fluorescence microscope to characterize growth of the Bacillus subtilis biofilm, in which the bacterial strain was triple fluorescence labeled for three main phenotypes: motile, matrix producing and sporulating cells. We used the feature point matching approach analyzing time lapse experimental movies to study the biofilm expansion rate. We found that the matrix producing cells dominate the biofilm expansion, at the biofilm edge, the expansion rate of matrix producing cells was almost the same as the velocity of the whole biofilm; however, the motile and sporulating cells were nearly rest. We also found that the biofilm expansion rate evolution relates to cell differentiation and biofilm morphology, and other micro-environments can influence the biofilm growth, such as nutrient, substrate hardness and colony competition. From our work, we get a deeper understanding of the biofilm growth, which can help us to control and to further disperse the biofilm.


Assuntos
Bacillus subtilis/fisiologia , Biofilmes/crescimento & desenvolvimento , Microscopia de Fluorescência/métodos , Imagem com Lapso de Tempo/métodos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Biofilmes/efeitos dos fármacos , Meios de Cultura/farmacologia , Fluorescência , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Fenótipo , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo , Temperatura
8.
Circ J ; 81(12): 1774-1782, 2017 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-28674268

RESUMO

BACKGROUND: The maximum axial diameter (MAD) of a fusiform abdominal aortic aneurysm (AAA) is an indicator of the risk of expansion or rupture. Apart from smoking and MAD itself, few expansion risk factors have been reported. In this study, we investigated expansion risk factors for AAA.Methods and Results:This retrospective cohort study included 176 patients who attended Tohoku University Hospital with infrarenal fusiform AAA. AAA expansion rate was determined on multidetector computed tomography, and the correlations between expansion rate and the clinical data were analyzed. The median expansion rate was 2.405 mm/year. On univariate analysis, a significant positive correlation with expansion rate was observed for the initial MAD (P<0.001) and significant negative correlations for oral angiotensin receptor blocker usage (P=0.025), height (P=0.005), body weight (P=0.017), total cholesterol (P=0.007), low-density lipoprotein cholesterol (P=0.004), and HbA1c (P=0.037). On logistic regression analysis, significant positive associations with expansion rate were observed for initial MAD (P<0.001) and oral steroid usage (P=0.029) and a negative association for height (P=0.041). CONCLUSIONS: Oral steroid usage is an important risk factor for AAA expansion, independent of other risk factors of atherosclerosis and MAD.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Idoso , Aneurisma da Aorta Abdominal/diagnóstico , Ruptura Aórtica , Estatura , Progressão da Doença , Humanos , Tomografia Computadorizada Multidetectores , Estudos Retrospectivos , Fatores de Risco , Esteroides/efeitos adversos , Esteroides/uso terapêutico
9.
Dig Dis Sci ; 62(5): 1286-1294, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28315029

RESUMO

BACKGROUND AND AIMS: Self-expandable metallic stent insertion has been a mainstream treatment for relieving the obstructive symptoms of malignant gastric outlet obstruction (MGOO), a late-stage complication of gastrointestinal malignancies. This study aims to investigate the predictive value of stent expansion rates in clinical outcomes in patients with MGOO. METHODS: Eighty-seven patients with inoperable MGOO receiving metallic stents were reviewed retrospectively from April 2010 to December 2014. Clinical outcomes, predictors of stent patency, and survival were analyzed. RESULTS: The technical and clinical success rates were 100 and 94.3%, respectively. The median stent patency time was 114 days (range 13-570 days). The median survival time was 133 days (range 13-1145 days). Stent dysfunctions occurred in 28 patients (32.2%), with restenosis accounting for the majority (82%). The stent expansion rate ≥75% at Day 1 predicted the stent patency [hazard ratio (HR) 0.12, P = 0.04]. However, it did not correlate with survival. Non-gastric cancer origins (HR 2.41, P = 0.002) and peritoneal carcinomatosis (HR 2.54, P = 0.001) correlated with poor survival. However, post-stent chemotherapy (HR 0.55, P = 0.03) was related to better outcome. The comparison of clinical outcomes of first and second stent insertions showed no significant difference in the stent expansion rate either at Day 0 and Day 1 (P = 0.97 and P = 0.57). CONCLUSIONS: Self-expandable metallic stent insertion is a safe and effective treatment for relieving the obstructive symptoms. The stent expansion rate ≥75% at Day 1 is a novel stent-related predictor of stent patency.


Assuntos
Obstrução da Saída Gástrica/cirurgia , Stents , Neoplasias Abdominais/complicações , Neoplasias Abdominais/cirurgia , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Obstrução da Saída Gástrica/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Complicações Pós-Operatórias
10.
Microsc Microanal ; 22(1): 63-70, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26810277

RESUMO

An original high-pressure microscopy chamber has been designed for real-time visualization of biological cell growth during high isostatic (gas or liquid) pressure treatments up to 200 MPa. This new system is highly flexible allowing cell visualization under a wide range of pressure levels as the thickness and the material of the observation window can be easily adapted. Moreover, the design of the observation area allows different microscope objectives to be used as close as possible to the observation window. This chamber can also be temperature controlled. In this study, the resistance and optical properties of this new high-pressure chamber have been tested and characterized. The use of this new chamber was illustrated by a real-time study of the growth of two different yeast strains - Saccharomyces cerevisiae and Candida viswanathii - under high isostatic gas pressure (30 or 20 MPa, respectively). Using image analysis software, we determined the evolution of the area of colonies as a function of time, and thus calculated colony expansion rates.


Assuntos
Técnicas Citológicas/instrumentação , Técnicas Citológicas/métodos , Gases , Pressão Hidrostática , Microscopia/instrumentação , Microscopia/métodos , Candida/citologia , Candida/crescimento & desenvolvimento , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento
11.
Materials (Basel) ; 17(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38591432

RESUMO

Using limestone powder (LP), the by-product of manufactured sand, to replace part of fly ash (FA) or manufactured sand could not only turn waste into treasure and decrease the price of concrete, but could also enhance the performance of concrete and reduce environmental pollution. However, the impact of various LP incorporation methods on the performance of mass concrete was inconsistent. In this paper, the effects of LP on the workability, compressive strength, constrained expansion rate, hydration temperature and impermeability of mass concrete were studied by replacing FA or manufactured sand alone and replacing FA and manufactured sand simultaneously. The results showed that the impact of LP on the performance of mass concrete was equal when it replaced FA alone and FA and manufactured sand at the same time. When the replacement amount was 20%, the workability, expansibility and early strength of concrete were improved, but the later strength and impermeability were slightly reduced. The workability, compressive strength, expansibility and impermeability of mass concrete were improved when manufactured sand was replaced alone, and the optimal dosage was 10%. The LP, moreover, reduced the hydration temperature peak of concrete in three kinds of mixing methods, but the temperature peak appeared earlier. At lower dosages, LP optimized pore structure and promoted the early hydration of cement through filler effects and nucleation effects. When LP replaced manufactured sand, the microstructure of concrete was more dense, so the replacement of manufactured sand had a better effect on the improvement of concrete properties. A reference value for the use of LP in mass concrete is provided in this study.

12.
Materials (Basel) ; 17(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063850

RESUMO

The physicochemical properties of steel slag were investigated using SEM and IR, and it was found that free calcium oxide and free magnesium oxide in steel slag produce calcium hydroxide when in contact with water, leading to volume expansion. Thus, the expansion rate of steel slag itself was first investigated, and it was found that the volume expansion of steel slag was more obvious in seven days after water immersion. Then, the cement dosages of 5% and 6% of the steel slag expansion rate and cement-stabilized gravel volume changes between the intrinsic link were further explored after the study found that the cement bonding effect can be partially inhibited due to the volume of expansion caused by the steel slag, so it can be seen that increasing the dosage of cement can reduce the volume expansion of steel slag cement-stabilized gravel with the same dosage of steel slag. Finally, a prediction model of the expansion rate of steel slag cement-stabilized gravel based on the BP (back propagation) neural network was established, which was verified to be a reliable basis for predicting the expansion rate of steel slag cement-stabilized aggregates and improving the accuracy of the proportioning design.

13.
Materials (Basel) ; 16(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629972

RESUMO

Mo, TiH2, Al and graphite elemental powders were used as starting materials for the activation reaction sintering process, which was employed to fabricate porous Mo2TiAlC2. The alteration of phase constitution, volume expansion, porosity, pore size and surface morphology of porous Mo2TiAlC2 with sintering temperatures ranging from 700 °C to 1500 °C were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and pore size tester. Both the pore formation mechanism and activation reaction process at each temperature stage were investigated. The experimental results illustrate that the sintered discs of porous Mo2TiAlC2 exhibit obvious volume expansion and pore structure change during the sintering process. Before 1300 °C, the volume expansion rate and porosity increase with the increment of temperature. However, with the sintering temperature above 1300 °C, the volume expansion rate and porosity decrease. At the final sintering temperature of 1500 °C, porous Mo2TiAlC2 with a volume expansion rate of 35.74%, overall porosity of 47.1%, and uniform pore structure was synthesized. The pore-forming mechanism of porous Mo2TiAlC2 is discussed, and the evolution of pressed pores, the removal of molding agents, the decomposition of TiH2, and the Kirkendall effect caused by different diffusion rates of elements in the diffusion reaction are all accountable for the formation of pores.

14.
J Thorac Dis ; 15(9): 4826-4835, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37868895

RESUMO

Background: Limited studies have focused on the performance of self-expandable valves (SEVs) and balloon-expandable valves (BEVs) in patients with dilatated ascending aorta (AA) undergoing transcatheter aortic valve replacement (TAVR). The present study compared the performance of widely used Edwards BEVs and domestic SEVs in patients with dilatated AA among Chinese population. Methods: We identified and reviewed 207 patients who had baseline AA diameter ≥40 mm and underwent transfemoral TAVR. Patients were divided into two groups: SEV and BEV. The SEVs were locally manufactured valves that have received Chinese regulatory approval (Venus-A, Taurus One, and VitaFlow), while the BEVs were Edwards Sapien XT and Sapien3. Procedural device success and post-procedural changes of AA diameters were compared. Results: The sample size of SEV group was larger than that of BEV group because BEVs were not available in China in the early clinical practice. The overall device success was slightly lower in SEV group compared with BEV group (84.2% vs. 95.8%, P=0.213). However, in the univariable and multivariable logistic regression analyses, only bicuspid aortic valve (BAV) was found to be an independent risk factor for device failure (OR: 2.632, CI: 1.107-6.257, P=0.029). During the median follow-up of 21 months, no statistical difference was found between the two groups regarding the overall survival (83.1%±4.7% vs. 95.8%±4.1%, P=0.533), and no aortic dissection nor rupture was observed. In a subgroup of patients who had follow-up CTs ≥12-month intervals, the AA diameter appeared to remain stable in SEV group with an aortic expansion rate of 0 (-0.4 to 0.8) mm (P=0.102), while it slightly enlarged in BEV group with an aortic expansion rate of 0.4 (-0.4 to 0.6) mm/y (P=0.038). In addition, the AA diameter also slightly enlarged in patients with BAV [0.2 (0 to 1.0) mm/y, P=0.015], while it remained stable in patients with tricuspid aortic valve (TAV) [0 (-0.8 to 0.6) mm/y, P=0.640]. Conclusions: In patients with dilatated AA who underwent TAVR, the type of THVs did not affect the procedural device success. BAV appeared to be a risk factor for both device failure and higher aortic expansion rate in these patients.

15.
Quant Imaging Med Surg ; 13(7): 4493-4503, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37456317

RESUMO

Background: The plaque imaging findings associated with the stent expansion rate (SER) of the carotid artery are not well known. The purpose of this study was to investigate the imaging findings associated with SER. Methods: It was a retrospective investigation. Based on the kind of carotid stents used, retrospective data from 89 patients who had carotid artery stenting (CAS) for atherosclerotic carotid stenosis were gathered and divided into two groups: open-cell stents and closed-cell stents. Patients underwent preoperative carotid high-resolution magnetic resonance vessel wall imaging (HR-VWI). Use HR-VWI to quantitatively evaluate carotid wall thickness and plaque components. Calculate SER using digital subtraction angiography (DSA). All patients' baseline and HR-VWI imaging features were retrospectively analyzed. Simple and multivariable linear regression analysis was used to determine the imaging findings associated with SER of open-cell and closed-cell stents. Results: A total of 89 patients (mean age, 70±8 years; 69 men) were included in the final analysis. Among 89 patients, 35 patients were treated with open-cell stents. Fifty-four patients were treated with closed-cell stents. In the open-cell stents group, the Maximum single-slice calcification circumference score, maximum wall thickness (WTmax), and total calcification location score with P<0.10 in the simple linear regression analysis were included in the multivariable linear regression analysis. The results of the multivariable linear regression revealed that only the Maximum single-slice calcification circumference score (ß=-9.35; 95% CI: -18.15 to -0.56; P=0.03) was associated with SER of open-cell stents. In the closed-cell stents group, the Maximum single-slice calcification circumference score, WTmax, maximum area percentage of calcification, calcification volume, and total calcification location score with P<0.10 in the simple linear regression analysis were included in the multivariable linear regression analysis. The results of the multivariable linear regression revealed that the Maximum area percentage of calcification (ß=-0.67; 95% CI: -1.29 to -0.05; P=0.03), Maximum single-slice calcification circumference score (ß=-8.43; 95% CI: -13.36 to -3.49; P=0.001) and total calcification location score (ß=-0.37; 95% CI: -1.08 to 0.09; P=0.02) were associated with SER of closed-cell stents. Conclusions: Calcified plaques are associated with SER of the carotid artery. Calcification circumference correlates with SER of open-cell stents. Calcification circumference, calcification area, and calcification location are related to SER of closed-cell stents, which may provide a new consideration for clinicians when choosing carotid artery stents.

16.
Polymers (Basel) ; 14(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36015533

RESUMO

In order to obtain high dielectric silicone rubber (SR)-based nanocomposites, graphene (Gr) was added by ultrasonication and mechanical mixing for the preparation of a microporous structure. It was discovered that the Gr content and the expansion rate had a great impact on the cellular structure. Based on the effects of the Gr content and the expansion rate on the dielectric property, hybrid materials were prepared and better properties appeared, as expected. For all samples, the dielectric constant increased with the Gr content until 3 wt% and then decreased. When the Gr content was 3 wt% and the expansion rate was 2, the dielectric constant reached 18.14 (1 kHz), which was 55% higher than that of the non-expansion sample (11.74) and several times that of the pure sample (3~6). Meanwhile, the dielectric loss was less than 0.01. This work proposed a method for producing high dielectric materials with important applications in the field of capacitors, sensors, and micro-resistors.

17.
Front Endocrinol (Lausanne) ; 12: 721213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394010

RESUMO

Background: Type 2 diabetes mellitus (T2DM) patients have a lower risk of abdominal aortic aneurysm (AAA) and its comorbidities, which might be associated with the usage of metformin. The objective of the study was to evaluate the role of metformin in the process of AAA development. Method: PubMed, Embase and Cochrane Library were searched up to May 15th, 2021. We implemented several methods including the risk of bias graph, GRADE system and funnel plot to assess the quality and possible bias of this study. Subgroup analysis and sensitivity analysis were applied to address quality differences and validate the robustness of the final results. Result: Ten articles were enrolled after screening 151 articles searched from databases. The pooled results showed that, compared with T2DM patients without metformin, metformin prescription was associated with a slower annual growth rate of the aneurysm (mean difference (MD) -0.67 cm [95% confidence interval (CI) -1.20 ~ -0.15 cm]). Besides, metformin exposure was associated with a lower frequency of AAA events (odds ratio (OR) 0.61 [95% CI 0.41-0.92]). Conclusion: Metformin alleviated both annual expansion rate and aneurysm rupture frequency in AAA patients with T2DM. Systematic Review Registration: PROSPERO, identifier https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=217859 (CRD42020217859).


Assuntos
Aneurisma da Aorta Abdominal/prevenção & controle , Metformina/uso terapêutico , Aneurisma da Aorta Abdominal/epidemiologia , Comorbidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Humanos , Hipoglicemiantes/uso terapêutico , Fatores de Risco
18.
Plants (Basel) ; 10(1)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440793

RESUMO

Predictions of future crop growth and yield under a changing climate require a precise knowledge of plant responses to their environment. Since leaf growth increases the photosynthesizing area of the plant, it occupies a central position during the vegetative phase. Rice is cultivated in diverse ecological zones largely differing in temperature and relative air humidity (RH). To investigate the effects of temperature and RH during day and night on leaf growth, one variety (IR64) was grown in a growth chamber using 9 day/night regimes around the same mean temperature and RH, which were combinations of 3 temperature treatments (30/20 °C, 25/25 °C, 20/30 °C day/night temperature) and 3 RH treatments (40/90%, 65/65%, 90/40% day/night RH). Day/night leaf elongation rates (LER) were measured and compared to leaf gas exchange measurements and leaf area expansion on the plant level. While daytime LER was mainly temperature-dependent, nighttime LER was equally affected by temperature and RH and closely correlated with leaf area expansion at the plant level. We hypothesize that the same parameters increasing LER during the night also enhance leaf area expansion via shifts in partitioning to larger and thinner leaves. Further, base temperatures estimated from LERs varied with RH, emphasizing the need to take RH into consideration when modeling crop growth in response to temperature.

19.
Ophthalmol Sci ; 1(1): 100005, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36246008

RESUMO

Purpose: To investigate atrophy expansion rate (ER) using ultra-widefield (UWF) fundus autofluorescence (FAF) in Stargardt disease (STGD1). Design: Retrospective, longitudinal study. Participants: Patients with biallelic ABCA4 mutations who were evaluated with UWF FAF and Heidelberg 30° × 30° and 55° × 55° FAF imaging. Methods: Patients with atrophy secondary to STGD1 were classified into genotype groups: group A, biallelic severe or null-like variants with early-onset disease; group B, 1 intermediate variant in trans with severe or null-like variant; and group C, 1 mild variant in trans with severe or null-like variant or late-onset disease. The boundaries of definitely decreased autofluorescence (DDAF) were outlined manually and areas (in square millimeters) were recorded at baseline and follow-up. Bland-Altman analysis was conducted to examine agreement between observers and devices. Linear mixed modeling was used to evaluate predictors of ER in DDAF area and square root area (SRA). Main Outcome Measures: Patient and ocular predictors of DDAF area ER and DDAF SRA ER included age at onset, duration of symptoms, genotype group, baseline visual acuity, and baseline atrophy size. Results: A total of 138 eyes from 69 patients (33 men [47%]; mean age ± standard deviation, 41 ± 20 years; range, 10-83 years) carrying 61 unique ABCA4 variants were recruited. Ultra-widefield FAF measurements were equivalent to Heidelberg 30° × 30° imaging. Baseline DDAF area was the only significant predictor of DDAF area ER (P < 0.001). Age at baseline and genotype group were predictors for DDAF SRA ER. Definitely decreased autofluorescence area ER ranged from 4.65 mm2/year (group A) to 0.62 mm2/year (group C). Conclusions: Ultra-widefield FAF is a feasible and reliable method for assessing atrophy ER in STGD1. The value of ABCA4 mutation severity in predicting atrophy ER warrants further investigation.

20.
J Gastrointest Cancer ; 51(4): 1118-1121, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32860615

RESUMO

PURPOSE: Liver transplantation is a curative treatment option for hepatocellular carcinoma. In this review, we aimed to review liver transplantation criteria for hepatocellular carcinoma and patient survivals. METHODS: We reviewed literature in terms of liver transplant criteria for hepatocellular carcinoma. Patient eligibility criteria, post-transplant survivals, tumor recurrence and expansion of Milan criteria rates were analyzed. RESULTS: The Milan criteria, after being published in 1996, have become for deceased donor liver transplantation in hepatocellular carcinoma worldwide. Later, many transplant centers published their own liver transplant criteria. Most of the criteria consisted of morphological tumor characteristics based on tumor size and number. The newest published one is Malatya criteria. The 5-year overall survival according the all of the criteria is greater than 50%. There were just one paper which compare criteria according to survival and Malatya criteria were the best amongst extended criteria with 5-year OS 79.7% in that study. CONCLUSION: It is clear that morphological criteria consisting only of tumor size and number are insufficient in patient selection for liver transplantation and should thus be combined with biological, inflammatory, radiological, pathological and genetic markers that predict the biological behavior of the tumor. Efforts to find the best criteria are still ongoing and 5-year overall survival should be greater than 60%.


Assuntos
Carcinoma Hepatocelular/terapia , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/terapia , Transplante de Fígado/normas , Recidiva Local de Neoplasia/epidemiologia , Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Humanos , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Seleção de Pacientes , Medição de Risco/métodos , Taxa de Sobrevida , Carga Tumoral
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