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1.
ACS Appl Mater Interfaces ; 13(38): 45315-45324, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34520665

RESUMO

Active targeted therapy for bowel cancer using untethered microrobots has attracted extensive attention. However, traditional microrobots face challenges, such as issues of mobility, biocompatibility, drug loading, sustained-release capabilities, and targeting accuracy. Here, we propose an untethered triple-configurational magnetic robot (TCMR) that is composed of three geometrically nested parts: actuation and guarding, anchoring and seeding, and drug release part. A targeting magnetic driving system actuates the TCMR along the predetermined trajectory to the target position. The pH-sensitive actuation and guarding part formed by electrodeposition is degraded in the intestinal environment and separates from the two other parts. A majority of magnetic nanoparticles encapsulated in this part are retrieved. The anchoring and seeding part anchors the lesion area and seeds the drug release part in the gaps of intestinal villi by hydrolysis. Ultimately, the drug release part containing the therapeutic completes the sustained release to prolong the duration of the therapeutic agent. Cytotoxicity and therapeutic tests reveal that TCMRs are biocompatible and suitable for targeted therapy and have good therapeutic performance. The newly designed TCMR will provide new ideas for targeted therapy, thus expanding the application scope of robotics technology in the biomedical field.

2.
J Cancer ; 12(20): 6254-6264, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539898

RESUMO

Background: The x-ray repair cross-complementing (XRCC) family is essential in DNA repair processes. The predictive roles of XRCCs remain unclear in ovarian carcinomas. Therefore, detecting the relationship between XRCCs expression and ovarian carcinomas prognosis is increasingly pivotal. Methods: Using the "Kaplan-Meier (KM) plotter" database, progression-free survival (PFS) and overall survival (OS) were utilized to evaluate the prognosis of XRCCs mRNA expression in ovarian carcinoma patients with clinical outcomes. Then, mRNA level and protein levels of XRCCs were assessed in normal ovarian cells and ovarian carcinoma cell lines by real-time qPCR, Western blotting and immunofluorescence analysis. Additionally, expression of the XRCCs protein in tissues from ovarian carcinomas and normal ovary was identified by immunohistochemical staining. Results: Higher mRNA levels of XRCC2 and XRCC9 predicted longer PFS and OS in all women with ovarian malignance, while elevated XRCC4 mRNA levels were linked to poor PFS and OS in all ovarian cancer patients. Elevated mRNA of XRCC2 was also correlated with better PFS in patients with serous ovarian carcinomas, and better PFS and OS in grade III and stage III+IV ovarian carcinomas patients. What's more, highly expressed levels of XRCC9 mRNA were also linked to favorable PFS and OS in patients with serous, grade III and stage III+IV ovarian carcinomas. Nevertheless, elevated mRNA expression of XRCC4 was linked to worse PFS and OS for patients with serous, grade III as well as all stages of ovarian malignance. Additionally, when compared to ovarian carcinoma cell lines, elevated mRNA and protein levels of XRCC2 and XRCC9 were detected in normal ovarian cells. Consistently, higher staining of XRCC2 and XRCC9 was also detected in normal ovarian cells than that in ovarian cancer cells. Then, higher staining levels of XRCC2 and XRCC9 were discovered in healthy control tissues than that in ovarian carcinoma tissues. Meanwhile, XRCC4 was identified to be overexpressed in tissues of ovarian malignance as compared to normal control tissues. However, XRCC4 mRNA and protein levels were lower in ovarian cancer cells than that in normal cell line. Conclusion: Elevated XRCC2 and XRCC9 expression levels were observed in normal ovarian cells and tissues than that in ovarian malignance cells and tissues, and exhibited better prognostic value especially in patients with serous, poor differentiated and late stage, suggesting that XRCC2 and XRCC9 may be potent prognostic markers in ovarian cancer patients and can guide personalized surveillance for ovarian malignance.

3.
Sensors (Basel) ; 21(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34300585

RESUMO

The number of wheat ears is an essential indicator for wheat production and yield estimation, but accurately obtaining wheat ears requires expensive manual cost and labor time. Meanwhile, the characteristics of wheat ears provide less information, and the color is consistent with the background, which can be challenging to obtain the number of wheat ears required. In this paper, the performance of Faster regions with convolutional neural networks (Faster R-CNN) and RetinaNet to predict the number of wheat ears for wheat at different growth stages under different conditions is investigated. The results show that using the Global WHEAT dataset for recognition, the RetinaNet method, and the Faster R-CNN method achieve an average accuracy of 0.82 and 0.72, with the RetinaNet method obtaining the highest recognition accuracy. Secondly, using the collected image data for recognition, the R2 of RetinaNet and Faster R-CNN after transfer learning is 0.9722 and 0.8702, respectively, indicating that the recognition accuracy of the RetinaNet method is higher on different data sets. We also tested wheat ears at both the filling and maturity stages; our proposed method has proven to be very robust (the R2 is above 90). This study provides technical support and a reference for automatic wheat ear recognition and yield estimation.


Assuntos
Redes Neurais de Computação , Triticum , Orelha , Aprendizagem , Aprendizado de Máquina
4.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2275-2289, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313044

RESUMO

The feedback relationship between organisms or ecosystems and environment has been a key issue in ecological research. Manipulative experiments with changing biological or environmental factors and large-scale field experiment networks were regarded as effective approaches to understand and accurately quantify the process and mechanisms underlying ecosystem response and adaptation to environmental changes. In recent years, a few networks have been developed, including large-scale networks of field physics simulation experiment (i.e., ECOTRON), ecosystem analysis and experiment platform (AnaEE), international Drought Network, Nutrient Network, and experiment networks based on regional ecological observation stations (i.e., USA-ILTER) at global scale. The development of continent-scale experiment network platform is attracting more attention from the academic community, and will play a more important role in understanding the process and mechanism underlying ecosystem responses to environmental change. We reviewed the development of method and experiment system of ecosystem manipulative experiments, and clearly pointed out that different experiments should form a joint collaborative system to answer fundamental scientific questions about the response and adaptation of ecosystem to global environment change. Manipulative experiments could be classified into four types: 1) Physiological and ecological experiments in closed laboratory equipment; 2) semi-open experiments with changing environmental factors in the field; 3) near-natural field experiments; 4) experiment networks based on field ecological station. Furthermore, we discussed the trends in network design of manipulative experiments focusing on ecosystem response and adaptation to environmental changes and the advantages of large-scale experiments based on natural environmental gradients. We put forward a proposal of integrating the technical advantages of different types of experiments and developing a new generation of field experiment network system. The study discussed the research system based on field experiment network, demonstrated the possibility to understand the patterns and mechanisms of the ecosystem short-term response and long-term adaptation to environmental changes, and proposed some equations to quantify the environmental response of ecosystems. The application of the design plan of the manipulative experiments network proposed here will greatly promote the scientific research level of ecosystems and environmental changes in China and even over the whole world, which has important scientific significance for the national response to climate change and ecological environmental construction.


Assuntos
Mudança Climática , Ecossistema , Aclimatação , China , Tecnologia
5.
BMC Urol ; 21(1): 77, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957905

RESUMO

PURPOSE: To compare the effects of two different methods of laparoscopic pyeloplasty for the treatment of crossing vessels. METHODS: From January 2016 to August 2019, 33 patients with ureteropelvic junction obstruction (UPJO) underwent laparoscopic pyeloplasty at our center, including 21 men and 12 women, ranging from 14 to 66 years of age. There were 20 and 13 cases on the left and right sides, respectively. Patients underwent laparoscopic pyeloplasty (Anderson-Hynes operation). During the operation, either a Hem-o-lok clip suspension or transposition was used to treat the crossing vessels. The double-J stent was removed 8 weeks after the operation. The clinical data of patients were collected and follow-ups were regularly performed after the operation. RESULTS: All the crossing vessels were successfully preserved, and none of them were severed during the operation. The average operation time was 210.6 ± 58.9 min in this group and the average time to manage the crossing vessel was 8.0 ± 3.5 min, 5.9 ± 1.4 min in the suspension group, and 11.7 ± 3.0 min in the transposition group. The dilation of the affected side was 4.8 ± 1.5 cm before operation and 1.2 ± 1.3 cm 3 months after operation. The difference was statistically significant (P < 0.05). Follow-up to February 2020 showed no significant changes in the kidney size in all patients and hydronephrosis was relieved. CONCLUSION: For UPJO patients with crossing vessel compression, the method of Hem-o-lok suspension or vascular transposition can be used to relieve crossing vascular compression and improve the success of pyeloplasty.


Assuntos
Pelve Renal/cirurgia , Laparoscopia , Artéria Renal/anormalidades , Artéria Renal/cirurgia , Obstrução Ureteral/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Adulto Jovem
6.
Phys Chem Chem Phys ; 23(11): 6880-6887, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33725039

RESUMO

Tuning the work functions of materials is of practical interest for maximizing the performance of microelectronic and (photo)electrochemical devices, as the efficiency of these systems depends on the ability to control electronic levels at surfaces and across interfaces. Perovskites are promising compounds to achieve such control. In this work, we examine the work functions of more than 1000 perovskite oxide surfaces (ABO3) using data-driven (machine-learning) analysis and identify the factors that determine their magnitude. While the work functions of the BO2-terminated surfaces are sensitive to the energy of the hybridized oxygen p bands, the work functions of the AO-terminated surfaces exhibit a much less trivial dependence with respect to the filling of the d bands of the B-site atom and of its electronic affinity. This study shows the utility of interpretable data-driven models in analyzing the work functions of cubic perovskites from a limited number of electronic-structure descriptors.

7.
J Back Musculoskelet Rehabil ; 34(4): 565-572, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33554887

RESUMO

BACKGROUND: Persisting shoulder stiffness adversely affects quality of life by causing pain and motion restrictions especially in patients with diabetes. OBJECTIVE: The aim of this study was to evaluate the outcomes of arthroscopic capsular release in patients with idiopathic shoulder stiffness. METHOD: A literature search was conducted in electronic databases and studies were selected by following precise eligibility criteria. Random-effects meta-analyses were performed to estimate the changes at latest follow-up in scores of the Constant, American Shoulder and Elbow Surgeons (ASES), and University of California at Los Angelis (UCLA) scales, Visual Analogue Scale (VAS), and shoulder range of motion. RESULTS: Nineteen studies were included. The follow-up duration was 42 months [95% confidence interval (CI): 32, 51]. Improvements in scores of the Constant, ASES, UCLA scales, and VAS were 48.3 [95% CI: 38.0, 58.6], 44.6 [95% CI: 24.6, 64.6], 19.3 [95% CI: 16.6, 22.0], and -6.1 [95% CI: -6.9, -5.4] respectively (P< 0.05 all). Improvements in the shoulder range of motion were: abduction 82.0 [95% CI: 65.0, 98.9]; forward flexion 75.9 [95% CI: 59.7, 92.1]; external rotation 43.2 [95% CI: 37.5, 49.0]; and internal rotation 25.4 [95% CI: 15.2, 35.5] degrees; P< 0.05 all). CONCLUSION: Arthroscopic capsular release effectively improves shoulder function in patients with idiopathic shoulder stiffness.


Assuntos
Liberação da Cápsula Articular , Artropatias/cirurgia , Articulação do Ombro/cirurgia , Artroscopia , Humanos , Medição da Dor , Amplitude de Movimento Articular , Rotação , Ombro , Resultado do Tratamento , Escala Visual Analógica
9.
Medicine (Baltimore) ; 100(2): e24047, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33466157

RESUMO

INTRODUCTION: Post-transplant lymphoproliferative disease (PTLD) is a series of proliferative diseases of the lymphatic system. Among patients receiving hematopoietic stem cell transplantation (HSCT), PTLD is a prevalent complication that severely affects rates of survival. Ultrasound plays an essential role in the early diagnosis of PTLD. Contrast-enhanced ultrasonography (CEUS) and CEUS-guided biopsy are critical procedures for tumor diagnosis. PATIENT CONCERNS: Herein, we report the case of a 40-year-old male patient with acute lymphoblastic leukemia who received HSCT more than 1 year ago. Sonography revealed a small hypoechoic nodule in the liver four months after HSCT. Eight months after HSCT, larger and more nodules were observed via ultrasound; CT was used to identify the lesions. DIAGNOSES: CEUS and CEUS-guided biopsy were performed, and the pathological diagnosis was PTLD. INTERVENTIONS: The final clinical diagnosis was PTLD, and cyclophosphamide, epirubicin, and dexamethasone were administered as chemotherapy. OUTCOMES: The patient was discharged after his condition improved. CONCLUSION: Ultrasound can be used to effectively detect lesions of PTLD early after HSCT. Furthermore, CEUS and CEUS-guided biopsy were effective for early confirmatory diagnoses of PTLD after HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/etiologia , Adulto , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Humanos , Transtornos Linfoproliferativos/diagnóstico por imagem , Masculino , Ultrassonografia/métodos
10.
Sci Total Environ ; 769: 144559, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33485199

RESUMO

It is well documented that warming can accelerate greenhouse gas (GHG) emissions, further inducing a positive feedback and reinforcing future climate warming. However, how different kinds of GHGs respond to various warming magnitudes remains largely unclear, especially in the cold regions that are more sensitive to climate warming. Here, we concurrently measured carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes and their total balance in an alpine meadow in response to three levels of warming (ambient, +1.5 °C, +3.0 °C). We found warming-induced increases in CH4 uptake, decreases in N2O emissions and increases in CO2 emissions at the annual basis. Expressed as CO2-equivalents with a global warming potential of 100 years (GWP100), the enhancement of CH4 uptake and reduction of N2O emissions offset only 9% of the warming-induced increase in CO2 emissions for 1.5 °C warming, and only 7% for 3.0 °C warming. CO2 emissions were strongly stimulated, leading to a significantly positive feedback to climate system, for 3.0 °C warming but less for 1.5 °C warming. The warming with 3.0 °C altered the total GHG balance mainly by stimulating CO2 emissions in the non-growing season due to warmer soil temperatures, longer unfrozen period, and increased soil water content. The findings provide an empirical evidence that warming beyond global 2 °C target can trigger a positive GHG-climate feedback and highlight the contribution from non-growing season to this positive feedback loop in cold ecosystems.

11.
J Mater Chem B ; 9(4): 1030-1039, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33398321

RESUMO

Small intestine-targeted drug delivery by oral administration has aroused the growing interest of researchers. In this work, the child-parent microrobot (CPM) as a vehicle protects the child microrobots (CMs) under a gastric acid environment and releases them in the small intestinal environment. The intelligent hydrogel-based CPMs with sphere, mushroom, red blood cell, and teardrop shapes are fabricated by an extrusion-dripping method. The CPMs package uniform CMs, which are fabricated by designed microfluidic (MF) devices. The fabrication mechanism and tunability of CMs and CPMs with different sizes and shapes are analyzed, modeled, and simulated. The shape of CPM can affect its drug release efficiency and kinetic characteristics. A vision-feedback magnetic driving system (VMDS) actuates and navigates CPM along the predefined path to the destination and continuously releases drug in the simulated intestinal fluid (SIF, a low Reynolds number (Re) regime) using a new motion control method with the tracking-learning-detection (TLD) algorithm. The newly designed CPM combines the advantages of powerful propulsion, good biocompatibility, and remarkable drug loading and release capacity at the intestinal level, which is expected to be competent for oral administration of small intestine-targeted therapy in the future.


Assuntos
Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Nanopartículas de Magnetita/química , Robótica , Células Cultivadas , Criança , Humanos , Dispositivos Lab-On-A-Chip , Fenômenos Magnéticos , Tamanho da Partícula , Robótica/instrumentação , Propriedades de Superfície
12.
ACS Appl Mater Interfaces ; 12(35): 39505-39514, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32805883

RESUMO

Cyclohexane-1,2,4,5-tetracarboxylic diimide with a nonconjugated core has been incorporated to bridge two conventional triphenylamine units. The obtained monomer has successfully hypsochromically shifted the maximum absorption wavelength by 10 nm in comparison to the one with a pyromellitic diimide bridge. Consequently, a colorless electrochromic (EC) polymer poly(bis(N,N-diphenyl-4-aminophenyl)cyclohexane-1,2,4,5-tetracarboxylic diimide) (PTPA-HDI) was electropolymerized on indium tin oxide (ITO)-coated glass. The morphology, absorption, and spectroelectrochemistry properties of polymer PTPA-HDI films electropolymerized by different scan cycles have been systematically investigated. It is found that comprehensive properties, such as color contrast and initial transparence, can be achieved for the polymer film electropolymerized by 15 scan cycles. Moreover, to realize colorless-to-black electrochromism, an asymmetric viologen derivative 1-(4-cyanophenyl)-1'-hexyl-4,4'-bipyridinium dihexafluorophosphate (HVCN) has been designed and straightforward synthesized. With the introduction of a cyanophenyl group and a hexyl chain on the two pyridinium units, colorless-to-green electrochromism can be realized for this processible viologen derivative. The absorption band at 495 nm of colorated PTPA-HDI compensates well for the valley in the absorption spectrum of colorated HVCN. Therefore, different types of colorless-to-black electrochromic devices (ECDs) are fabricated using polymer PTPA-HDI-deposited ITO electrode and HVCN-based gel electrolyte. Such a supporting electrolyte-free ECD with binary electrochromes exhibits fast coloration, high color contrast, and excellent reversibility. Furthermore, an encryption ECD is demonstrated by switching a black two-dimensional code. In addition, an autodigital display is integrated on a smart window and hence different functions can be realized in a single ECD. Overall, this study may facilitate the understanding of the EC behaviors of binary electrochromes and present a new path to design multifunctional displays.

13.
Small ; 16(23): e1906701, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32378351

RESUMO

A magnetic urchin-like microswimmer based on sunflower pollen grain (SPG) that can pierce the cancer cell membrane and actively deliver therapeutic drugs is reported. These drug loaded microperforators are fabricated on a large scale by sequentially treating the natural SPGs with acidolysis, sputtering, and vacuum loading. The microswimmers exhibit precise autonomous navigation and obstacle avoidance in complex environments via association with artificial intelligence. Assemblies of microswimmers can further enhance individual motion performance and adaptability to complicated environments. Additionally, the experimental results demonstrate that microswimmers with nanospikes can accomplish single-cell perforation for direct delivery under an external rotating magnetic field. Drugs encapsulated in the inner cavity of the microperforators can be accurately delivered to a specific site via remote control. These dual-action microswimmers demonstrate good biocompatibility, high intelligence, precision in single-cell targeting, and sufficient drug loading, presenting a promising avenue for many varieties of biomedical applications.


Assuntos
Inteligência Artificial , Neoplasias , Humanos , Campos Magnéticos , Magnetismo
14.
ACS Nano ; 14(4): 4235-4243, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32223186

RESUMO

Controlling the thermal conductivity of semiconductors is of practical interest in optimizing the performance of thermoelectric and phononic devices. The insertion of inclusions of nanometer size in a semiconductor is an effective means of achieving such control; it has been proposed that the thermal conductivity of silicon could be reduced to 1 W/m/K using this approach and that a minimum in the heat conductivity would be reached for some optimal size of the inclusions. Yet the experimental verification of this design rule has been limited. In this work, we address this question by studying the thermal properties of silicon metalattices that consist of a periodic distribution of spherical inclusions with radii from 7 to 30 nm, embedded into silicon. Experimental measurements confirm that the thermal conductivity of silicon metalattices is as low as 1 W/m/K for silica inclusions and that this value can be further reduced to 0.16 W/m/K for silicon metalattices with empty pores. A detailed model of ballistic phonon transport suggests that this thermal conductivity is close to the lowest achievable by tuning the radius and spacing of the periodic inhomogeneities. This study is a significant step in elucidating the scaling laws that dictate ballistic heat transport at the nanoscale in silicon and other semiconductors.

15.
Glob Chang Biol ; 26(7): 4147-4157, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32301539

RESUMO

Soil nitrification, an important pathway of nitrogen transformation in ecosystems, produces soil nitrate that influences net primary productivity, while the by-product of nitrification, nitrous oxide, is a significant greenhouse gas. Although there have been many studies addressing the microbiology, physiology, and impacting environment factors of soil nitrification at local scales, there are very few studies on soil nitrification rate over large scales. We conducted a global synthesis on the patterns and controlling factors of soil nitrification rate normalized at 25°C by compiling 3,140 observations from 186 published articles across terrestrial ecosystems. Soil nitrification rate tended to decrease with increasing latitude, especially in the Northern Hemisphere, and varied largely with ecosystem types. The soil nitrification rate significantly increased with mean annual temperature (MAT), soil nitrogen content, microbial biomass carbon and nitrogen, soil ammonium, and soil pH, but decreased with soil carbon:nitrogen and carbon:nitrogen of microbial biomass. The total soil nitrogen content contributed the most to the variations of global soil nitrification rate (total coefficient = 0.29) in structural equation models. The microbial biomass nitrogen (MBN; total coefficient = 0.19) was nearly of equivalent importance relative to MAT (total coefficient = 0.25) and soil pH (total coefficient = 0.24) in determining soil nitrification rate, while soil nitrogen and pH influenced soil nitrification via changing soil MBN. Moreover, the emission of soil nitrous oxide was positively related to soil nitrification rate at a global scale. This synthesis will advance our current understanding on the mechanisms underlying large-scale variations of soil nitrification and benefit the biogeochemical models in simulating global nitrogen cycling.


Assuntos
Nitrificação , Solo , Ecossistema , Nitrogênio/análise , Ciclo do Nitrogênio , Microbiologia do Solo
16.
Angew Chem Int Ed Engl ; 59(18): 7122-7130, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32067320

RESUMO

BN-embedded oligomers with different pairs of BN units were synthesized by electrophilic borylation. Up to four pairs of BN units were incorporated in the large polycyclic aromatic hydrocarbons (PAHs). Their geometric, photophysical, electrochemical, and Lewis acidic properties were investigated by X-ray crystallography, optical spectroscopy, and cyclic voltammetry. The B-N bonds show delocalized double-bond characteristics and the conjugation can be extended through the trans-orientated aromatic azaborine units. Calculations reveal the relatively lower aromaticity for the inner azaborine rings in the BN-embedded PAH oligomers. The frontier orbitals of the longer oligomers are delocalized over the inner aromatic rings. Consequently, the inner moieties of the BN-embedded PAH oligomers are more active than the outer parts. This is confirmed by a simple oxidation reaction, which has significant effects on the aromaticity and the intramolecular charge-transfer interactions.

17.
J Hazard Mater ; 389: 121880, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31843402

RESUMO

Low-level radioactive wastes are commonly immobilized in cementitious materials, where cement-based material can incorporate radionuclides into their crystal structure. Specifically, ettringite (Ca6Al2(OH)12(SO4)3∙26H2O) is known to stabilize anionic species, which is appealing for waste streams with radioactive iodine (129I) that persists as iodide (I-) and iodate (IO3-) in the cementitious nuclear waste repository. However, the structural information and immobilization mechanisms of iodine species in ettringite remain unclear. The present results suggested minimal I- incorporation into ettringite (0.05 %), whereas IO3- exhibited a high affinity for ettringite via anion substitution for SO42- (96 %). The combined iodine K-edge extended X-ray absorption fine structure (EXAFS) spectra and first-principles calculations using density functional theory (DFT) suggested that IO3- was stabilized in ettringite by hydrogen bonding and electrostatic forces. Substituting IO3- for SO42- was energetically favorable by -0.41 eV, whereas unfavorable substitution energy of 4.21 eV was observed for I- substitution. Moreover, the bonding charge density analysis of the substituted IO3- and I- anions into the ettringite structure revealed the interaction between intercalated ions with the structural water molecules. These results provided valuable insight into the long-term stabilization of anionic iodine species and their migration in cementitious nuclear waste repository or alkaline environments.

18.
J Parasitol ; 105(6): 878-881, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31730392

RESUMO

The microsporidium Nosema sp. SE is a pathogen that infects the beet armyworm Spodoptera exigua. The complete sequence of its 4,302-base pair (bp) ribosomal ribonucleic acid (rRNA) gene region was obtained by polymerase chain reaction amplification and sequencing. The rRNA organization of Nosema sp. SE was 5'-large subunit (LSU) rRNA-internal transcribed spacer-small subunit (SSU) rRNA-intergenic spacer-5S-3', which corresponded to the pattern of Nosema bombycis. Phylogenetic analysis based on LSU rRNA and SSU rRNA both indicated that the parasite had a close relationship with other true Nosema species, confirming that Nosema sp. SE belongs to true Nosema group of the genus Nosema.


Assuntos
Beta vulgaris/parasitologia , Nosema/genética , Spodoptera/microbiologia , Animais , DNA Fúngico/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/genética , Estágios do Ciclo de Vida , Nosema/classificação , Nosema/crescimento & desenvolvimento , Nosema/ultraestrutura , Filogenia , RNA Ribossômico/química , Alinhamento de Sequência
19.
Oncol Lett ; 18(5): 4789-4797, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31611989

RESUMO

Cell-cycle-associated and expression-elevated protein in tumor (CREPT) functions as a cell cycle modulator that enhances the transcription of cyclin D1 by interacting with RNA polymerase II. CREPT has been identified to be overexpressed in various human cancer types; however, the expression and significance of CREPT in renal cell carcinoma (RCC) has remained largely elusive. In the present study, increased expression of CREPT was identified in 46.7% RCC tissues compared with adjacent normal tissue (31.1%; P=0.032) using immunohistochemistry. Furthermore, overexpression of CREPT was significantly associated with the Tumor-Node-Metastasis stage (χ2=11.967, P=0.001) and Fuhrman grade (χ2=15.453, P<0.001). In addition, increased expression of CREPT was associated with poor overall survival (P=0.021) and disease-free survival (P=0.015) of patients according to Kaplan-Meier analysis. Cellular function assays demonstrated that knockdown of CREPT in the 786-O and 769P RCC cell lines suppressed their proliferative, colony formation, migratory and invasive capacity and led to cell cycle arrest in the G1 phase. In addition, the western blotting analysis demonstrated that CREPT may control the cell cycle through downregulation of cyclin D1 and c-myc. Collectively, the overexpression of CREPT was indicated to be a negative prognostic factor for RCC, and CREPT may serve as a novel therapeutic target for the treatment of RCC.

20.
Nanoscale ; 11(39): 18382-18392, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573587

RESUMO

Recent progress of untethered mobile micromotors has shown immense potential for targeted drug delivery in vivo. However, designing a wireless micromotor with high maneuverability and biocompatibility and achieving controlled drug release with high efficiency at a specific position remains a great challenge. Herein, we present a pine pollen-based micromotor (PPBM) and demonstrate its potential application as a cargo carrier for targeted drug delivery. These multifunctional biohybrid micromotors were massively and inexpensively fabricated by the encapsulation of magnetic particles (Fe3O4) and medicine into the two hollow air sacs of pine pollen, via vacuum loading. PPBMs successfully inherit the intrinsic functionalities of pine pollen: structural uniformity, morphological stability, biocompatibility, autofluorescence (AF) and physicochemical robustness. Under an external magnetic field, the loaded Fe3O4 enables individual and swarm PPBMs to propel precisely in complex biological fluids. Capitalizing on the magnetic nanoparticle aggregation phenomenon under a powerful magnetic field, controlled release of the therapeutic cargo is achieved using a fluid field generated by the rotating magnetic agglomerate. The biohybrid micromotors reported here turn natural pine pollen into active and controllable cargo carriers for biomedical applications.


Assuntos
Doxorrubicina , Campos Magnéticos , Nanopartículas de Magnetita/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Células HeLa , Humanos
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