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1.
Sci Rep ; 14(1): 17766, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090146

RESUMO

Patients with end stage renal disease (ESRD) are at high risk of developing upper tract urothelial carcinoma (UTUC). Due to high recurrence rate of UTUC in contralateral kidney and ureter, and high risk of complications related to surgery and anesthesia, whether it's necessary to remove both kineys and ureters at one time remains in debate. We utilized Taiwanese UTUC Registry Database to valuate the difference of oncological outcomes and perioperative complications between patients with ESRD with unilateral and bilateral UTUC receiving surgical resection. Patients with ESRD and UTUC were divided into three groups, unilateral UTUC, previous history of unilateral UTUC with metachronous contralateral UTUC, and concurrent bilatetral UTUC. Oncological outcomes, perioperative complications, and length of hospital stays were investiaged. We found that there is no diffence of oncological outcomes including overall survival, cancer specific survival, disease free survival and bladder recurrence free survival between these three groups. Complication rate and length of hospital stay are similar. Adverse oncological features such as advanced tumor stage, lymph node involvement, lymphovascular invasion, and positive surgical margin would negatively affect oncological outcomes.


Assuntos
Falência Renal Crônica , Nefroureterectomia , Complicações Pós-Operatórias , Humanos , Nefroureterectomia/métodos , Masculino , Feminino , Falência Renal Crônica/cirurgia , Falência Renal Crônica/complicações , Idoso , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento , Neoplasias Ureterais/cirurgia , Neoplasias Ureterais/complicações , Neoplasias Ureterais/mortalidade , Neoplasias Ureterais/patologia , Carcinoma de Células de Transição/cirurgia , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/complicações , Tempo de Internação , Taiwan/epidemiologia , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Neoplasias Renais/complicações , Recidiva Local de Neoplasia/epidemiologia
2.
PLoS One ; 19(7): e0307696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39038022

RESUMO

It has been reported that Ywhah (14-3-3η) reduces glycolysis. However, it remains unclear about the downstream mechanism by which glycolysis is regulated by 14-3-3η in cardiac hypertrophy. As an important regulator, Yes-associated protein (YAP) interacts with 14-3-3η to participate in the initiation and progression of various diseases in vivo. In this study, the model of H9C2 cardiomyocyte hypertrophy was established by triiodothyronine (T3) or rotenone stimulation to probe into the action mechanism of 14-3-3η. Interestingly, the overexpression of 14-3-3η attenuated T3 or rotenone induced cardiomyocyte hypertrophy and decreased glycolysis in H9C2 cardiomyocytes, whereas the knockdown of 14-3-3η had an opposite effect. Mechanistically, 14-3-3η can reduce the expression level of YAP and bind to it to reduce its nuclear translocation. In addition, changing YAP may affect the expression of lactate dehydrogenase A (LDHA), a glycolysis-related protein. Meanwhile, LDHA is also a possible target for 14-3-3η to mediate glycolysis based on changes in pyruvate, a substrate of LDHA. Collectively, 14-3-3η can suppress cardiomyocyte hypertrophy via decreasing the nucleus translocation of YAP and glycolysis, which indicates that 14-3-3η could be a promising target for inhibiting cardiac hypertrophy.


Assuntos
Proteínas 14-3-3 , Cardiomegalia , Glicólise , L-Lactato Desidrogenase , Miócitos Cardíacos , Tri-Iodotironina , Proteínas de Sinalização YAP , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Animais , Ratos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia , L-Lactato Desidrogenase/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Proteínas de Sinalização YAP/metabolismo , Linhagem Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Isoenzimas/metabolismo , Isoenzimas/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
3.
Mol Cell Endocrinol ; 590: 112271, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38759835

RESUMO

Hyperthyroidism is becoming increasingly important as an independent risk factor for cardiovascular disease, eventually resulting in cardiac hypertrophy and heart failure. The 14-3-3 protein family subtypes regulate many cellular processes in eukaryotes by interacting with a diverse array of client proteins. Considering that the 14-3-3η protein protects cardiomyocytes by affecting mitochondrial function, exploring the biological influence and molecular mechanisms by which 14-3-3η alleviates the cardiac hypertrophy of hyperthyroidism is imperative. In vivo and in vitro, RT-PCR, Western blot, and Mitochondrial tracking assay were performed to understand the molecular mechanism of thyroxine-induced cardiomyocyte hypertrophy. HE staining, transmission electron microscopy, and immunofluorescence were used to observe intuitively changes of hearts and cardiomyocytes. The in vivo and in vitro results indicated that overexpression of the 14-3-3η ameliorated thyroxine-induced cardiomyocyte hypertrophy, whereas knockdown of the 14-3-3η protein aggravated thyroxine-induced cardiomyocyte hypertrophy. Additionally, overexpression of the 14-3-3η protein reduces thyroxine-induced mitochondrial damage and mitophagy in cardiomyocytes. Overexpression of 14-3-3η protein improves excessive mitophagy in the myocardium caused by thyroxine and thus prevents cardiac hypertrophy.


Assuntos
Proteínas 14-3-3 , Cardiomegalia , Mitofagia , Miócitos Cardíacos , Tiroxina , Animais , Masculino , Camundongos , Ratos , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/genética , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Mitofagia/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Tiroxina/farmacologia
4.
Adv Mater ; : e2403835, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814633

RESUMO

This state-of-the-art review is geared toward elucidating the molecular understanding of the carbon-based flame-retardant mechanisms for polymers via holistic characterization combining detailed analytical assessments and computational material science. The use of carbon-based flame retardants, which include graphite, graphene, carbon nanotubes (CNTs), carbon dots (CDs), and fullerenes, in their pure and functionalized forms are initially reviewed to evaluate their flame retardancy performance and to determine their elevation of the flammability resistance on various types of polymers. The early transition metal carbides such as MXenes, regarded as next-generation carbon-based flame retardants, are discussed with respect to their superior flame retardancy and multifunctional applications. At the core of this review is the utilization of cutting-edge molecular dynamics (MD) simulations which sets a precedence of an alternative bottom-up approach to fill the knowledge gap through insights into the thermal resisting process of the carbon-based flame retardants, such as the formation of carbonaceous char and intermediate chemical reactions offered by the unique carbon bonding arrangements and microscopic in-situ architectures. Combining MD simulations with detailed experimental assessments and characterization, a more targeted development as well as a systematic material synthesis framework can be realized for the future development of advanced flame-retardant polymers.

5.
Pestic Biochem Physiol ; 200: 105839, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582601

RESUMO

Lepidopteran insects are refractory to RNA interference (RNAi) response, especially to orally delivered double-stranded RNA (dsRNA). High nuclease activity in the midgut lumen is proposed as one of the major reasons for RNAi insensitivity. We identified three dsRNase genes highly expressed in the midgut of fall armyworm (FAW), Spodoptera frugiperda. The genomic region harboring those three dsRNase genes was deleted using the CRISPR-Cas9-mediated genome editing method. A homozygous line with deletion of three dsRNase genes was produced. dsRNA degradation by midgut lumen contents of mutant larvae was lower than in wild-type larvae. Feeding dsRNA targeting the inhibitor of apoptosis (IAP) gene increased knockdown of the target gene and mortality in mutants compared to wild-type larvae. These results suggest that dsRNases in the midgut contribute to RNAi inefficiency in FAW. Formulations that protect dsRNA from dsRNase degradation may improve RNAi efficiency in FAW and other lepidopteran insects.


Assuntos
Sistemas CRISPR-Cas , RNA de Cadeia Dupla , Animais , Interferência de RNA , Spodoptera/genética , Spodoptera/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , Insetos/genética , Larva/genética , Larva/metabolismo
6.
Adv Sci (Weinh) ; 11(21): e2310115, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38491872

RESUMO

In this work, 2D ferromagnetic M3GeTe2 (MGT, M = Ni/Fe) nanosheets with rich atomic Te vacancies (2D-MGTv) are demonstrated as efficient OER electrocatalyst via a general mechanical exfoliation strategy. X-ray absorption spectra (XAS) and scanning transmission electron microscope (STEM) results validate the dominant presence of metal-O moieties and rich Te vacancies, respectively. The formed Te vacancies are active for the adsorption of OH* and O* species while the metal-O moieties promote the O* and OOH* adsorption, contributing synergistically to the faster oxygen evolution kinetics. Consequently, 2D-Ni3GeTe2v exhibits superior OER activity with only 370 mV overpotential to reach the current density of 100 mA cm-2 and turnover frequency (TOF) value of 101.6 s-1 at the overpotential of 200 mV in alkaline media. Furthermore, a 2D-Ni3GeTe2v-based anion-exchange membrane (AEM) water electrolysis cell (1 cm2) delivers a current density of 1.02 and 1.32 A cm-2 at the voltage of 3 V feeding with 0.1 and 1 m KOH solution, respectively. The demonstrated metal-O coordination with abundant atomic vacancies for ferromagnetic M3GeTe2 and the easily extended preparation strategy would enlighten the rational design and fabrication of other ferromagnetic materials for wider electrocatalytic applications.

7.
Aesthetic Plast Surg ; 48(6): 1067-1075, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37816946

RESUMO

BACKGROUND: Although laser Doppler imaging (LDI) accurately delineates a hypoperfused area to help target hyaluronidase treatment, laser speckle contrast imaging (LSCI) is more appropriate for assessing microvascular hemodynamics and has greater reproducibility than LDI. This study investigated the use of LSCI in the evaluation and treatment of six patients who developed vascular complications after facial dermal filler injections. METHODS: The areas of vascular occlusion were accurately defined in real time by LSCI and were more precise than visual inspections or photographic evidence for guiding needling and hyaluronidase treatment. RESULTS: All patients had achieved satisfactory outcomes as early as Day 2 of treatment and no procedure-related complications were reported after a median follow-up of 9.5 (7-37) days. CONCLUSION: LSCI accurately and noninvasively delineated vascular occlusions in real time among patients experiencing complications of facial dermal filler injections. Moreover, LSCI was more accurate than visual and photographic evaluations. Clinicians can use LSCI to reliably follow-up therapeutic outcomes after salvage interventions for vascular occlusions. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Humanos , Preenchedores Dérmicos/efeitos adversos , Imagem de Contraste de Manchas a Laser , Hialuronoglucosaminidase , Reprodutibilidade dos Testes , Indução Percutânea de Colágeno , Técnicas Cosméticas/efeitos adversos , Ácido Hialurônico
8.
J Agric Food Chem ; 71(42): 15497-15505, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37843053

RESUMO

Azadirachtin has been used to control agricultural pests for a long time; however, the molecular mechanism of azadirachtin on lepidopterans is still not clear. In this study, the fourth instar larvae of fall armyworm were fed with azadirachtin, and then the ecdysis was blocked in the fourth instar larval stage (L4). The prothoracic glands (PGs) of the treated larvae were dissected for RNA sequencing to determine the effect of azadirachtin on ecdysis inhibition. Interestingly, one of the PG-enriched genes, the nuclear hormone receptor 3 (HR3), was decreased after azadirachtin treatment, which plays a critical role in the 20-hydroxyecdysone action during ecdysis. To deepen the understanding of azadirachtin on ecdysis, the HR3 was knocked out by using the CRISPR/Cas9 system, while the HR3 mutants displayed embryonic lethal phenotype; thus, the stage-specific function of HR3 during larval molting was not enabled to unfold. Hence, the siRNA was injected into the 24 h L4 larvae to knock down HR3. After 96 h, the injected larvae were blocked in the old cuticle during ecdysis which is consistent with the azadirachtin-treated larvae. Taken together, we envisioned that the inhibition of ecdysis in the fall armyworm after the azadirachtin treatment is due to an interference with the expression of HR3 in PG, resulting in larval mortality. The results in this study specified the understanding of azadirachtin on insect ecdysis and the function of HR3 in lepidopteran in vivo.


Assuntos
Muda , Receptores Citoplasmáticos e Nucleares , Animais , Muda/genética , Larva/metabolismo , Spodoptera/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
9.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446760

RESUMO

The effect of varying the weight percentage composition (wt.%) of low-cost expandable graphite (EG), ammonium polyphosphate (APP), fibreglass (FG), and vermiculite (VMT) in polyurethane (PU) polymer was studied using a traditional intumescent flame retardant (IFR) system. The synergistic effect between EG, APP, FG, and VMT on the flame retardant properties of the PU composites was investigated using SEM, TGA, tensile strength tests, and cone calorimetry. The IFR that contained PU composites with 40 wt.% EG displayed superior flame retardant performance compared with the composites containing only 20 w.t.% or 10 w.t.% EG. The peak heat release rate, total smoke release, and carbon dioxide production from the 40 wt.% EG sample along with APP, FG, and VMT in the PU composite were 88%, 93%, and 92% less than the PU control sample, respectively. As a result, the synergistic effect was greatly influenced by the compactness of the united protective layer. The PU composite suppressed smoke emission and inhibited air penetrating the composite, thus reducing reactions with the gas volatiles of the material. SEM images and TGA results provided positive evidence for the combustion tests. Further, the mechanical properties of PU composites were also investigated. As expected, compared with control PU, the addition of flame-retardant additives decreased the tensile strength, but this was ameliorated with the addition of FG. These new PU composite materials provide a promising strategy for producing polymer composites with flame retardation and smoke suppression for construction materials.


Assuntos
Retardadores de Chama , Grafite , Poliuretanos , Polímeros , Polifosfatos
10.
Cancers (Basel) ; 15(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37444626

RESUMO

Metastatic castration-resistant prostate cancer (mCRPC) is a progressive stage of prostate cancer that often spreads to the bone. Radium-223, a bone-targeting radiopharmaceutical, has been shown to improve the overall survival in mCRPC in patients without visceral metastasis. However, the impact of prior systemic therapy on the treatment outcome of mCRPC patients receiving radium-223 remains unclear. This study aimed to investigate the optimal choice of systemic therapy before radium-223 in mCRPC patients. The study included 41 mCRPC patients who received radium-223 therapy, with 22 receiving prior enzalutamide and 19 receiving prior abiraterone. The results showed that the median overall survival was significantly longer in the enzalutamide group than in the abiraterone group (25.1 months vs. 14.8 months, p = 0.049). Moreover, the number of patients requiring blood transfusion was higher in the abiraterone group than in the enzalutamide group (9.1% vs. 26.3%, p = 0.16). The study also found that the number of doses of Radium-223 received was significantly associated with overall survival (≥5 vs. <5, HR 0.028, 95%CI 0.003-0.231, p = 0.001). Our study provides insights into the optimal treatment choice for mCRPC prior to radium-223, indicating that enzalutamide prior to radium-223 administration may have better outcomes compared to abiraterone in mCRPC patients without visceral metastasis.

11.
Cancers (Basel) ; 15(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36831576

RESUMO

INTRODUCTION: Sniffer dogs can diagnose lung cancer. However, the diagnostic yields of different samples and training methods for lung cancer remain undetermined. OBJECTIVE: Six dogs were trained in three stages with the aim of improving the diagnostic yield of lung cancer by comparing training methods and specimens. METHODS: The pathological tissues of 53 lung cancer patients and 6 non-lung cancer patients in the Department of Thoracic Surgery of Kaohsiung Chang Gung Hospital were collected, and the exhaled breath samples and urine samples were collected. Urine and exhaled breath samples were also collected from 20 healthy individuals. The specimens were sent to the Veterinary Department of Pingtung University of Science and Technology. RESULTS: The dogs had a very low response rate to urine target samples in the first and second stages of training. The experimental results at the second stage of training found that after lung cancer tissue training, dogs were less likely to recognize lung cancer and healthy controls than through breath target training: the response rate to exhaled breathing target samples was about 8-55%; for urine target samples, it was only about 5-30%. When using exhaled air samples for training, the diagnosis rate of these dogs in lung cancer patients was 71.3% to 97.6% (mean 83.9%), while the false positive rate of lung cancer in the healthy group was 0.5% to 27.6% (mean 7.6%). Compared with using breathing target samples for training, the diagnosis rate of dogs trained with lung cancer tissue lung cancer was significantly lower (p < 0.05). The sensitivity and specificity of lung cancer tissue training (50.4% and 50.1%) were lower than the exhaled breath target training (91.7% and 85.1%). There is no difference in lung cancer diagnostic rate by sniff dogs among lung cancer histological types, location, and staging. CONCLUSION: Training dogs using breathing target samples to train dogs then to recognize exhaled samples had a higher diagnostic rate than training using lung cancer tissue samples or urine samples. Dogs had a very low response rate to urine samples in our study. Six canines were trained on lung cancer tissues and breathing target samples of lung cancer patients, then the diagnostic rate of the recognition of exhaled breath of lung cancer and non-lung cancer patients were compared. When using exhaled air samples for training, the diagnosis rate of these dogs in lung cancer patients was 71.3% to 97.6% (mean 83.9%), while the false positive rate of lung cancer in the healthy group was 0.5% to 27.6% (mean 7.6%). There was a significant difference in the average diagnosis rate of individual dog and overall dogs between the lung cancer group and the healthy group (p < 0.05). When using lung cancer tissue samples for training, lung cancer diagnosis rate of these dogs among lung cancer patients was only 15.5% to 40.9% (mean 27.7%). Compared with using breathing target samples for training, the diagnosis rate of dogs trained with lung cancer tissue lung cancer was significantly lower (p < 0.05). The sensitivity and specificity of lung cancer tissue training (50.4% and 50.1%) were lower than the exhaled breath target training (91.7% and 85.1%). The diagnostic rate of lung cancer by sniffer dogs has nothing to do with the current stage of lung cancer, pathologic type, and the location of tumor mass. Even in stage IA lung cancer, well-trained dogs can have a diagnostic rate of 100%. Using sniffer dogs to screen early lung cancer may have good clinical and economic benefits.

12.
CRISPR J ; 5(6): 813-824, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36374965

RESUMO

Methoprene, a juvenile hormone (JH) analog, is widely used for insect control, but its mode of action is not known. To study methoprene action in the yellow fever mosquito, Aedes aegypti, the E93 (ecdysone-induced transcription factor) was knocked out using the CRISPR-Cas9 system. The E93 mutant pupae retained larval tissues similar to methoprene-treated insects. These insects completed pupal ecdysis and died as pupa. In addition, the expression of transcription factors, broad complex and Krüppel homolog 1 (Kr-h1), increased and that of programmed cell death (PCD) and autophagy genes decreased in E93 mutants. These data suggest that methoprene functions through JH receptor, methoprene-tolerant, and induces the expression of Kr-h1, which suppresses the expression of E93, resulting in a block in PCD and autophagy of larval tissues. Failure in the elimination of larval tissues and the formation of adult structures results in their death. These results answered long-standing questions on the mode of action of methoprene.


Assuntos
Aedes , Febre Amarela , Animais , Metoprene/farmacologia , Metoprene/metabolismo , Aedes/genética , Aedes/metabolismo , Febre Amarela/genética , Edição de Genes , Sistemas CRISPR-Cas/genética , Metamorfose Biológica/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Hormônios Juvenis/genética , Hormônios Juvenis/farmacologia , Hormônios Juvenis/metabolismo , Pupa/genética , Pupa/metabolismo , Larva/genética , Larva/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
Front Genet ; 13: 942884, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35899187

RESUMO

In insects, the shedding of the old exoskeleton is accomplished through ecdysis which is typically followed by the expansion and tanning of the new cuticle. Four neuropeptides, eclosion hormone (EH), ecdysis triggering hormone (ETH), crustacean cardioactive peptide (CCAP) and bursicon (Bur) are known to control ecdysis. However, the regulation of these neuropeptide genes is still poorly understood. Here, we report that in the red flour beetle (RFB) Tribolium castaneum and the fall armyworm (FAW) Spodoptera frugiperda, knockdown or knockout of the SoxC gene caused eclosion defects. The expansion and tanning of wings were not complete. In both RFB and FAW, the knockdown or knockout of SoxC resulted in a decrease in the expression of EH gene. Electrophoretic mobility shift assays revealed that the SfSoxC protein directly binds to a motif present in the promoter of SfEH. The luciferase reporter assays in Sf9 cells confirmed these results. These data suggest that transcription factor SoxC plays a key role in ecdysteroid induction of genes coding for neuropeptides such as EH involved in the regulation of insect eclosion.

14.
J Pers Med ; 12(2)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35207743

RESUMO

BACKGROUND AND OBJECTIVES: Vertebral compression fracture is a major health care problem worldwide due to its direct and indirect negative influence on health-related quality of life and increased health care costs. Although a percutaneous surgical intervention with balloon kyphoplasty or metal expansion, the SpineJack, along with bone cement augmentation has been shown to efficiently restore and fix the lost vertebral height, 21-30% vertebral body height loss has been reported in the literature. Furthermore, the effect of the augmentation approaches and the loss of body height on the biomechanical responses in physiological activities remains unclear. Hence, this study aimed to compare the mechanical behavior of the fractured lumbar spine with different restored body heights, augmentation approaches, and posterior fixation after kyphoplasty using the finite element method. Furthermore, different augmentation approaches with bone cement and bone cement along with the SpineJack were also considered in the simulation. MATERIALS AND METHODS: A numerical lumbar model with an incomplete burst fracture at L3 was used in this study. Two different degrees of restored body height, namely complete and incomplete restorations, after kyphoplasty were investigated. Furthermore, two different augmentation approaches of the fractured vertebral body with bone cement and SpineJack along with bone cement were considered. A posterior instrument (PI) was also used in this study. Physiological loadings with 400 N + 10 Nm in four directions, namely flexion, extension, lateral bending, and axial rotation, were applied to the lumbar spine with different augmentation approaches for comparison. RESULTS: The results indicated that both the bone cement and bone cement along with the SpineJack could support the fractured vertebral body to react similarly with an intact lumbar spine under identical loadings. When the fractured body height was incompletely restored, the peak stress in the L2-L3 disk above the fractured vertebral body increased by 154% (from 0.93 to 2.37 MPa) and 116% (from 0.18 to 0.39 MPa), respectively, in the annular ground substance and nucleus when compared with the intact one. The use of the PI could reduce the range of motion and facet joint force at the implanted levels but increase the facet joint force at the upper level of the PI. CONCLUSIONS: In the present study, complete restoration of the body height, as possible in kyphoplasty, is suggested for the management of lumbar vertebral fractures.

15.
Molecules ; 27(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35011524

RESUMO

Building polymers implemented into building panels and exterior façades have been determined as the major contributor to severe fire incidents, including the 2017 Grenfell Tower fire incident. To gain a deeper understanding of the pyrolysis process of these polymer composites, this work proposes a multi-scale modelling framework comprising of applying the kinetics parameters and detailed pyrolysis gas volatiles (parent combustion fuel and key precursor species) extracted from Molecular Dynamics models to a macro-scale Computational Fluid Dynamics fire model. The modelling framework was tested for pure and flame-retardant polyethylene systems. Based on the modelling results, the chemical distribution of the fully decomposed chemical compounds was realised for the selected polymers. Subsequently, the identified gas volatiles from solid to gas phases were applied as the parent fuel in the detailed chemical kinetics combustion model for enhanced predictions of toxic gas, charring, and smoke particulate predictions. The results demonstrate the potential application of the developed model in the simulation of different polymer materials without substantial prior knowledge of the thermal degradation properties from costly experiments.

16.
Int J Pharm ; 612: 121293, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34808267

RESUMO

The aim of this study was to evaluate the device performance of a new design by comparing with a typical commercial DPI. Computational fluid dynamics (CFD) coupled with the discrete element method (DEM) collision has been utilized in this study to characterize and examine the flow field and particle transportation, respectively. A typical commercial DPI and an in-house designed novel DPI with distinct design features were compared to explore their dispersion capabilities and suitability for delivery to the respiratory tract. For this exploration, realistic oral to larynx and tracheobronchial airway models consisting of bio-relevant features were adopted to enhance practical feasibility. Distinct aerosol performances were observed between the two DPIs in the respiratory tract, where the in-house DPI, in comparison with the commercial DPI, has shown approximately 30% lower deposition fraction in the mouth-throat region with approximately 7% higher escape rate in the tracheobronchial region under the identical inhalation condition. This observation demonstrates that a novel in-house designed DPI provides higher device efficiency over the selected typical commercial DPI.


Assuntos
Inaladores de Pó Seco , Sistema Respiratório , Administração por Inalação , Aerossóis , Simulação por Computador , Desenho de Equipamento , Hidrodinâmica , Tamanho da Partícula , Pós
17.
Molecules ; 26(21)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34771069

RESUMO

Biomass-derived carbon has been recognised as a green, economic and promising flame retardant (FR) for polymer matrix. In this paper, it is considered that the two-dimensional (2D) structure of carbonised peanut shells (PS) can lead to a physical barrier effect on polymers. The carbonised sample was prepared by the three facile methods, and firstly adopted as flame retardants for epoxy resin. The results of thermal gravimetric analysis (TGA) and cone calorimeter tests indicate that the carbon combined with nano Cobalt provides the most outstanding thermal stability in the current study. With 3 wt.% addition of the FR, both peak heat release rate (pHRR) and peak smoke production rate (PSPR) decrease by 37.9% and 33.3%, correspondingly. The flame retardancy mechanisms of the FR are further explored by XPS and TG-FTIR. The effectiveness of carbonised PS can be mainly attributed to the physical barrier effect derived by PS's 2D structure and the catalysis effect from Cobalt, which contribute to form a dense char layer.

18.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34614481

RESUMO

Biofuel cell (BFC) is a kind of bio-cell based on biological enzymes. The enzyme as a catalyst can interconvert renewable and sustainable energy into each other more rapidly, such as the biochemical energy in glucose and ethanol into electrical energy. In this work, artificial blood vessel and fuel cell are based on polyaniline/thermoplastic polyurethane (PANI/TPU) fiber membrane with an average fiber diameter of 1300 nm, a film thickness of 167µm, and a permeability of 18.4 mm s-1. The PANI/TPU fiber membrane was prepared by electrospinning and followedin situpolymerization. The membrane has good flexibility and mechanical properties, and can be stretched up to 200%. The advantages of good hydrophilicity, biocompatibility and high porosity make it possible to efficiently load glucose oxidase and laccase. The prepared BFC can stably output a voltage of 50 mV in simulated blood, and the output electrical signal changes significantly with the change of glucose concentration, which may be used in implantable devices or blood glucose monitoring.

19.
J Affect Disord ; 295: 264-270, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34482058

RESUMO

BACKGROUND: Major depressive disorder (MDD) is the most common mental disorder associated with suicide attempts. When a patient first visits the clinic, clinicians are often expected to make concrete diagnose about acute suicidal risk. However, the timeliness of suicide attempts correlates with patients with MDD has not been tested. METHODS: We divided 1718 first-episode and untreated MDD outpatients into those who did not have suicide attempts (non-attempts), recent suicide attempters (≤14 days before assessment) and long - dated suicide attempters (> 30 days before assessment). Positive Symptom Scale of Positive and Negative Syndrome Scale (PANSS), the 17-item Hamilton Depression Scale, 14 - item Hamilton Anxiety Scale, and clinical global impression of severity scale (CGI-S) was assessed. Body mass index, some glycolipid metabolism and thyroid hormone parameters were measured. A gradient-boosted decision trees statistical model was used to generate equally weighted classification for distinguishing recent and long - dated suicide attempters from non-attempts. RESULTS: The classifier identified higher excitement, hostility, anxiety, depression symptoms and higher free thyroxine (FT4) as risk factors for recent suicide attempters with an estimated accuracy of 87% (sensitivity, 59.1%; specificity, 61.2 %). For long - dated suicide attempters' risk factors, single status, higher anxiety and hostility symptoms, higher LDLC and lower BMI, the estimated accuracy was 88% (sensitivity, 52.8%; specificity, 49.6%). CONCLUSIONS: Risk factors for suicide attempt among patients with MDD can be identified by integrating demographic, clinical, and biological variables as early as possible during the first time see a doctor.


Assuntos
Transtorno Depressivo Maior , Tentativa de Suicídio , Ansiedade , Estudos Transversais , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Humanos , Fatores de Risco
20.
Polymers (Basel) ; 13(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34502893

RESUMO

Room temperature vulcanized (RTV) silicone rubber filled with aluminum trihydrate (ATH) is substantially engaged in electrical outdoor insulation applications. The pristine silicone rubber is highly combustible. ATH filled silicone rubber offers excellent electrical insulation but lacks in providing adequate flame retardancy. This short communication reports the novel results on improved flame retardancy of pristine and ATH filled silicone rubber whilst retaining the electrical insulation properties to a great extent. Results suggest that the presence of only one percent of graphene nanoplatelets with ATH sharply reduces the heat release rate and rate of smoke release. A minor reduction in dielectric breakdown strength and volume resistivity is noticed. Furthermore, permittivity and dielectric loss at power frequency suggest that a marginal 1% concentration of nanoplatelet with ATH is an excellent approach to fabricate flame retardant silicone rubber with an acceptable electrical insulation level.

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