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1.
Adv Healthc Mater ; 13(14): e2303824, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38303578

RESUMO

The limitations of protein-based hydrogels, including their insufficient mechanical properties and restricted biological functions, arise from the highly specific functions of proteins as natural building blocks. A potential solution to overcome these shortcomings is the development of protein-protein hydrogels, which integrate structural and functional proteins. In this study, a protein-protein hydrogel formed by crosslinking bovine serum albumin (BSA) and a genetically engineered intrinsically disordered collagen-like protein (CLP) through Ag─S bonding is introduced. The approach involves thiolating lysine residues of BSA and crosslinking CLP with Ag+ ions, utilizing thiolation of BSA and the free-cysteines of CLP. The resulting protein-protein hydrogels exhibit exceptional properties, including notable plasticity, inherent self-healing capabilities, and gel-sol transition in response to redox conditions. In comparison to standalone BSA hydrogels, these protein-protein hydrogels demonstrate enhanced cellular viability, and improved cellular migration. In vivo experiments provide conclusive evidence of accelerated wound healing, observed not only in murine models with streptozotocin (Step)-induced diabetes but also in zebrafish models subjected to UV-burn injuries. Detailed mechanistic insights, combined with assessments of proinflammatory cytokines and the expression of epidermal differentiation-related proteins, robustly validate the protein-protein hydrogel's effectiveness in promoting wound repair.


Assuntos
Hidrogéis , Soroalbumina Bovina , Cicatrização , Peixe-Zebra , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Soroalbumina Bovina/química , Camundongos , Compostos de Sulfidrila/química , Bovinos , Diabetes Mellitus Experimental , Queimaduras/terapia , Queimaduras/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno/química
2.
Biomater Sci ; 11(24): 7748-7758, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37753880

RESUMO

Genetically encoded collagen-like protein-based hydrogels have demonstrated remarkable efficacy in promoting the healing process in diabetic patients. However, the current methods for preparing these hydrogels pose significant challenges due to harsh reaction conditions and the reliance on chemical crosslinkers. In this study, we present a genetically encoded approach that allows for the creation of protein hydrogels without the need for chemical additives. Our design involves the genetic encoding of paired-cysteine residues at the C- and N-terminals of a meticulously engineered collagen-like recombination protein. The protein-based hydrogel undergoes a gel-sol transition in response to redox stimulation, achieving a gel-sol transition. We provide evidence that the co-incubation of the protein hydrogel with 3T3 cells not only enhances cell viability but also promotes cell migration. Moreover, the application of the protein hydrogel significantly accelerates the healing of diabetic wounds by upregulating the expression of collagen-1α (COL-1α) and Cytokeratin 14 (CK-14), while simultaneously reducing oxidant stress in the wound microenvironment. Our study highlights a straightforward strategy for the preparation of redox-responsive protein hydrogels, removing the need for additional chemical agents. Importantly, our findings underscore the potential of this hydrogel system for effectively treating diabetic wounds, offering a promising avenue for future therapeutic applications.


Assuntos
Diabetes Mellitus , Hidrogéis , Camundongos , Animais , Humanos , Hidrogéis/farmacologia , Cicatrização , Colágeno/metabolismo , Diabetes Mellitus/tratamento farmacológico , Oxirredução
3.
Environ Sci Pollut Res Int ; 30(26): 68691-68700, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37126181

RESUMO

It is a great challenge to develop photocatalysts for the degradation of organic pollutants in the aqueous environment, especially those with excellent catalytic performance under visible light conditions. In this work, using graphene oxide (GO) as an electron shuttle agent and carrier, a hybrid of ZIF-8/NH2-MIL-125(Ti) and GO (ZIF-8/NH2-MIL-125(Ti)/GO) was prepared by a simple two-step solvothermal method. The morphology, structure, and combination of the synthesized catalysts were studied. The results showed that graphene oxide and ZIF-8 formed an in situ load on NH2-MIL-125(Ti). The construction of hybrid materials significantly improved the catalytic activity of NH2-MIL-125(Ti) in the visible light range. The degradation activity of the synthesized catalyst was further tested with reactive red dye. The results showed that the catalyst exhibited excellent catalytic removal efficiency for active red, with a degradation rate of 99.8% within 2 h. The prepared hybrid materials have good application prospects in the field of organic pollutant treatment in water.


Assuntos
Poluentes Ambientais , Grafite , Óxidos , Titânio , Água , Corantes , Eletrônica , Luz
4.
Huan Jing Ke Xue ; 44(3): 1319-1327, 2023 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-36922193

RESUMO

A total of 98 samples were collected to analyze the seasonal variation and source apportionment of carbonaceous components, especially brown carbon (BrC), of PM2.5in Luoyang during 2018-2019. The concentrations of organic carbon (OC) and elemental carbon (EC) ranged from (7.04±1.82) µg·m-3to(23.81±8.68) µg·m-3and (2.96±1.4) µg·m-3to (13.41±7.91) µg·m-3, respectively, showing the seasonal variation of being high in winter and low in summer; the carbonaceous fraction and secondary organic aerosol percentages were higher by 8.33%-141.03% and by 0.77%-63.14%, respectively, compared with that in 2015. The light absorption cross section (MAC) values showed different seasonal variations with the concentration of carbonaceous fraction, shown in descending order as autumn (7.67 m2·g-1)>winter (5.65 m2·g-1)>spring (5.13 m2·g-1)>summer (3.84 m2·g-1). The MAC values ranged from 3.84 to 7.67 m2·g-1 at 445 nm, which was lower than that in coal ash. Seasonal variation in light absorption and the contribution of BrC to total light absorption (babs,BrC,405 nm, babs,BrC,405 nm/babs,405 nm) in descending order was winter (31.57 Mm-1, 33%), autumn (11.40 Mm-1, 25%), spring (4.88 Mm-1, 23%), and summer (2.12 Mm-1, 21%). The proportion of carbonaceous components decreased as haze episodes evolved, whereas the contribution of light absorption of BrC increased, highlighting the important contribution of BrC to the total light absorption. The results of PMF and correlation coefficients of babs,BrC,405 nm and PM2.5 components indicated that motor vehicles and secondary nitrate contributed 27.7% and 24.0%, respectively. Our findings have significant scientific implications for the deep controlling of carbonaceous aerosol, especially for BrC, in Luoyang in the future.

5.
Clin Imaging ; 93: 75-82, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36413877

RESUMO

PURPOSE: To assess differences in the mammographic and sonographic appearance of breast cancer in African American (AA) and Non-Latina White (NLW) women. METHODS: We identified AA and NLW women with biopsy proven ductal carcinoma in situ or invasive breast cancer between June 1, 2015 and May 31, 2018. Racial differences in Breast Imaging and Reporting Data System (BI-RADS) imaging features were analyzed by imaging cohorts, i.e. screen detected vs. clinical presentation, using logistic regression adjusted for histology and molecular subtypes. RESULTS: We analyzed 270 AA women with 278 cancers (166 screen detected, 112 clinical) and 586 NLW women with 599 cancers (397 screen detected, 202 clinical). Compared with NLW women, AA women had higher rates of non-dense breast composition (almost entirely fatty 12.0% vs. 4.6%, scattered fibroglandular 50.9% vs. 45.2%; overall P < 0001) in both cohorts and were less likely to have screen detected architectural distortion, (odds ratio (OR) = 0.38, 95% CI 0.18-0.80). AA women were less likely than NLW women to have screen detected irregular than oval/round masses (mammography: OR = 0.36, 95% CI 0.19-0.68; sonography: OR = 0.48, 95% CI 0.24-0.94), and more likely to present clinically with high density masses (OR = 3.03, 95% CI 1.12-8.20) demonstrating posterior enhancement (OR = 3.02, 95% CI 1.11-8.27). CONCLUSION: There are racial differences in the mammographic and sonographic appearance of breast cancer even after accounting for higher rates of triple negative breast cancer in AA women. Understanding these differences may provide breast imagers with a framework to approach breast cancer diagnosis in the AA population in clinical practice.


Assuntos
Negro ou Afro-Americano , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , População Branca , Mamografia , Densidade da Mama
6.
Nat Commun ; 13(1): 3882, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794100

RESUMO

Mitochondrial dynamics can regulate Major Histocompatibility Complex (MHC)-I antigen expression by cancer cells and their immunogenicity in mice and in patients with malignancies. A crucial role in the mitochondrial fragmentation connection with immunogenicity is played by the IRE1α-XBP-1s axis. XBP-1s is a transcription factor for aminopeptidase TPP2, which inhibits MHC-I complex cell surface expression likely by degrading tumor antigen peptides. Mitochondrial fission inhibition with Mdivi-1 upregulates MHC-I expression on cancer cells and enhances the efficacy of adoptive T cell therapy in patient-derived tumor models. Therefore mitochondrial fission inhibition might provide an approach to enhance the efficacy of T cell-based immunotherapy.


Assuntos
Dinâmica Mitocondrial , Neoplasias , Animais , Endorribonucleases , Complexo Principal de Histocompatibilidade , Camundongos , Dinâmica Mitocondrial/fisiologia , Neoplasias/terapia , Proteínas Serina-Treonina Quinases
7.
Phys Chem Chem Phys ; 23(35): 19862-19871, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525133

RESUMO

Bimodal HDPE models were designed for extension-induced crystallization imitating the architecture of industrial bimodal HDPE copolymerized with ethylene and 1-butene, 1-hexene, or 1-octene. Crystallites of bimodal HDPE experienced the emergence of precursors, shish nuclei, and lamellae. The compact conformation of branched polymers impeded the rolling-over, deposition, and folding of chains on the substrate, and thus the formation of nuclei and lamella. Moreover, this retardation was intensified with the rising branch density and length, causing a depression of crystallinity and an increment of tie-chains concentration. Besides, when branches were all located on long chains, the compact conformation enlarged the resistance to the disentanglement of main chains, thus relatively fewer branched long chains were involved in the precursors or nuclei, resulting in the attenuation of lamella formation. Furthermore, for ethyl branched polymers, the coexistent orthorhombic and monoclinic crystallites were built up, and a few expanded monoclinic cells occurred for butyl branches because of the larger butyl reeling into lamella, while hexagonal crystals were created for ethyl/1-hexyl copolymers because of cocrystallization. Additionally, relative to ethyl, larger butyl and hexyl were preferential to be repelled outside crystals to form tie-chains, and hexyl branched polymers acquired relatively fewer tie-chains because of hexagonal eutectoid.

8.
Front Plant Sci ; 11: 972, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32719700

RESUMO

Bacterial blight, which is one of the most common soybean diseases, is responsible for considerable yield losses. In this study, a novel Xanthomonas vasicola strain was isolated from the leaves of soybean plants infected with bacterial blight under field conditions. Sequencing the X. vasicola genome revealed type-III effector-coding genes. Moreover, the hrpG deletion mutant was constructed. To identify the soybean genes responsive to HrpG, two chromosome segment substitution lines (CSSLs) carrying the wild soybean genome, but with opposite phenotypes following Xanthomonas inoculations, were used to analyze gene expression networks based on RNA sequencing at three time points after inoculations with wild-type Xanthomonas or the hrpG deletion mutant. To further identify the hub genes underlying soybean responses to HrpG, the genes located on the substituted chromosome segments were examined. Finally, a combined analysis with the QTLs for resistance to Xanthomonas identified 35 hub genes in the substituted chromosomal segments that may help regulate soybean responses to Xanthomonas and HrpG. Furthermore, two candidate genes in the CSSLs might play pivotal roles in response to Xanthomonas.

9.
Front Plant Sci ; 11: 453, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508850

RESUMO

In some legume-rhizobium symbioses, host specificity is influenced by rhizobial type III effectors-nodulation outer proteins (Nops). However, the genes encoding host proteins that interact with Nops remain unknown. In this study, we aimed to identify candidate soybean genes associated with NopD, one of the type III effectors of Sinorhizobium fredii HH103. The results showed that the expression pattern of NopD was analyzed in rhizobia induced by genistein. We also found NopD can be induced by TtsI, and NopD as a toxic effector can induce tobacco leaf death. In 10 soybean germplasms, NopD played a positively effect on nodule number (NN) and nodule dry weight (NDW) in nine germplasms, but not in Kenjian28. Significant phenotype of NN and NDW were identified between Dongnong594 and Charleston, Suinong14 and ZYD00006, respectively. To map the quantitative trait locus (QTL) associated with NopD, a recombinant inbred line (RIL) population derived from the cross between Dongnong594 and Charleston, and chromosome segment substitution lines (CSSLs) derived from Suinong14 and ZYD00006 were used. Two overlapping conditional QTL associated with NopD on chromosome 19 were identified. Two candidate genes were identified in the confident region of QTL, we found that NopD could influence the expression of Glyma.19g068600 (FBD/LRR) and expression of Glyma.19g069200 (PP2C) after HH103 infection. Haplotype analysis showed that different types of Glyma.19g069200 haplotypes could cause significant nodule phenotypic differences, but Glyma.19g068600 (FBD/LRR) was not. These results suggest that NopD promotes S. fredii HH103 infection via directly or indirectly regulating Glyma.19g068600 and Glyma.19g069200 expression during the establishment of symbiosis between rhizobia and soybean plants.

10.
Mol Plant Microbe Interact ; 33(6): 798-807, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32186464

RESUMO

In soybean (Glycine max)-rhizobium interactions, the type III secretion system (T3SS) of rhizobium plays a key role in regulating host specificity. However, the lack of information on the role of T3SS in signaling networks limits our understanding of symbiosis. Here, we conducted an RNA sequencing analysis of three soybean chromosome segment substituted lines, one female parent and two derived lines with different chromosome-substituted segments of wild soybean and opposite nodulation patterns. By analyzing chromosome-linked differentially expressed genes in the substituted segments and quantitative trait loci (QTL)-assisted selection in the substituted-segment region, genes that may respond to type III effectors to mediate plant immunity-related signaling were identified. To narrow down the number of candidate genes, QTL assistant was used to identify the candidate region consistent with the substituted segments. Furthermore, one candidate gene, GmDRR1, was identified in the substituted segment. To investigate the role of GmDRR1 in symbiosis establishment, GmDRR1-overexpression and RNA interference soybean lines were constructed. The nodule number increased in the former compared with wild-type soybean. Additionally, the T3SS-regulated effectors appeared to interact with the GmDDR1 signaling pathway. This finding will allow the detection of T3SS-regulated effectors involved in legume-rhizobium interactions.


Assuntos
Genes de Plantas , Glycine max/genética , Rhizobium/fisiologia , Simbiose , Sistemas de Secreção Tipo III , Locos de Características Quantitativas , Análise de Sequência de RNA , Transdução de Sinais , Glycine max/microbiologia
11.
J Prosthet Dent ; 123(1): 163-172, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30982620

RESUMO

STATEMENT OF PROBLEM: Selective laser melting (SLM) Ti-6Al-4V has been used for removable partial dentures, but the impact of SLM Ti-6Al-4V build orientation is not evident. PURPOSE: The purpose of this in vitro study was to investigate the microstructure and properties of SLM Ti-6Al-4V clasps with different build orientations compared with cast Ti-6Al-4V clasps. MATERIAL AND METHODS: Forty-eight clasps were made from Ti-6Al-4V alloys-by SLM with 3 different build orientations (SLM0, SLM45, and SLM90) and cast (CAST) as a control. The microstructure was investigated by using a metallographic microscope and a confocal laser scanning microscope. The fit and surface roughness of the clasps were measured, and the physical properties were evaluated. In addition, the von Mises stresses in the clasps were calculated by finite element analysis. All specimens were then subjected to insertion and removal tests in artificial saliva to model 5 years of clinical use. After these tests, 3-point bend tests were used to analyze the fracture surface of the clasp arms, which were observed by using a scanning electron microscope. All data were statistically analyzed (α=.05). RESULTS: The microstructure of the Ti-6Al-4V specimens was a comixture of α+ß phases. In addition, growth directions of ß grains were approximately parallel to the build orientation, with acicular α grains present between ß grains. SLM0 and SLM45 had significantly higher roughness than SLM90. Even though the fit was inferior to that of SLM90, SLM0 and SLM45 still performed better than cast specimens (P<.05). The finite element analysis showed that the maximum von Mises stress was located on the middle part of the retainer arms and that the values of the 0.50-mm undercut clasps were much lower than the elastic limit. In addition, the decrease of retentive force in SLM90 clasps was less than that of the CAST group (P<.05). CAST clasps showed brittle fracture, whereas all SLM clasps showed ductile fracture. CONCLUSIONS: The microstructure of SLM Ti-6Al-4V affected the properties of clasps by changing the anisotropy of specimens. Among the tested groups, SLM90 clasps had the best fit, the lowest surface roughness, and the best fatigue resistance. Furthermore, SLM Ti-6Al-4V clasps could be engaged into 0.50-mm undercuts.


Assuntos
Prótese Parcial Removível , Grampos Dentários , Lasers , Teste de Materiais , Propriedades de Superfície , Resistência à Tração , Titânio
12.
Mol Genet Genomics ; 294(4): 1049-1058, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30982151

RESUMO

Symbiotic nitrogen fixation is the main source of nitrogen for soybean growth. Since the genotypes of rhizobia and soybean germplasms vary, the nitrogen-fixing ability of soybean after inoculation also varies. A few studies have reported that quantitative trait loci (QTLs) control biological nitrogen fixation traits, even soybean which is an important crop. The present study reported that the Sinorhizobium fredii HH103 gene rhcJ belongs to the tts (type III secretion) cluster and that the mutant HH103ΩrhcJ can clearly decrease the number of nodules in American soybeans. However, few QTLs of nodule traits have been identified. This study used a soybean (Glycine max (L.) Merr.) 'Charleston' × 'Dongnong 594' (C × D, n = 150) recombinant inbred line (RIL). Nodule traits were analysed in the RIL population after inoculation with S. fredii HH103 and the mutant HH103ΩrhcJ. Plants were grown in a greenhouse with a 16-h light cycle at 26 °C and an 8-h dark cycle at 18 °C. Then, 4 weeks after inoculation, plants were harvested for evaluation of nodule traits. Through QTL mapping, 16 QTLs were detected on 8 chromosomes. Quantitative PCR (qRT-PCR) and RNA-seq analysis determined that the genes Glyma.04g060600, Glyma.18g159800 and Glyma.13g252600 might interact with rhcJ.


Assuntos
Glycine max/microbiologia , Locos de Características Quantitativas , Sinorhizobium fredii/crescimento & desenvolvimento , Sistemas de Secreção Tipo III/genética , Mapeamento Cromossômico , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Família Multigênica , Mutação , Melhoramento Vegetal , Proteínas de Plantas/genética , Nódulos Radiculares de Plantas/crescimento & desenvolvimento , Nódulos Radiculares de Plantas/microbiologia , Sinorhizobium fredii/genética , Sinorhizobium fredii/metabolismo , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Sistemas de Secreção Tipo III/metabolismo
13.
RSC Adv ; 9(26): 14599-14608, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35516317

RESUMO

Herein, a porous heddle of poly(vinyl butyral) (PVB) was successfully prepared by thermally induced phase separation with PEG400. A phase diagram of PVB was presented, and the effects of various parameters, such as polymer concentration, extrusion temperature, quenching temperature and take-up speed, on the morphology and properties of the PVB porous heddle were investigated. The pore size and porosity of the heddle increase as the extrusion temperature increases. Furthermore, upon increasing the quenching temperature during the TIPS process, the pore size and mechanical properties decrease, whereas porosity increases. In addition, due to the substantially unchanged crystallinity of the PVB heddle, the tensile strength increases since porosity decreases with the increasing take-up speed. The porosity of the prepared PVB porous heddle reached up to 74.63% when the PVB concentration, the quenching temperature and the extrusion temperature were 20 wt%, 0 °C and 170 °C, respectively. Thus, this porous heddle exhibiting a biconnected structure and significant mechanical properties is promising in the field of porous carrier materials.

14.
RSC Adv ; 9(24): 13631-13645, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35519588

RESUMO

Polytetrafluoroethylene (PTFE) porous membranes are widely used for high-temperature filtration. The polytetrafluoroethylene nanofiber membranes for fine particulate filtration were prepared by sintering the precursor electrospun polytetrafluoroethylene/polyvinyl/boric acid alcohol composite membranes. The effects of PTFE/PVA mass ratio and sintering temperature on the morphology and properties of the prepared membranes were investigated to obtain the PTFE nanofibers with different diameters, and the film has been characterized by SEM, TG, XRD, FT-IR, and EDS, and the mechanical and hydrophobic properties of the membranes were also investigated. The PTFE nanofiber membranes after sintering had nanofiber and nanowire structures. Moreover, the membranes were tested in air filtration. The filtration efficiency and pressure drop were tested to evaluate the membrane permeability and separation properties. The results showed a high filtration efficiency (98%) and a low pressure drop (90 Pa) for 300 nm sodium chloride aerosol particles at a 30 L min-1 airflow velocity and the hydrophobic membranes showed durable self-cleaning properties, which suggested that the PTFE nanofiber membranes were a promising candidate for high temperature filtration applications.

15.
Int J Mol Sci ; 19(11)2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30400148

RESUMO

In some legume⁻rhizobium symbioses, host specificity is influenced by rhizobial nodulation outer proteins (Nops). However, the genes encoding host proteins that interact with Nops remain unknown. We generated an Ensifer fredii HH103 NopP mutant (HH103ΩNopP), and analyzed the nodule number (NN) and nodule dry weight (NDW) of 10 soybean germplasms inoculated with the wild-type E. fredii HH103 or the mutant strain. An analysis of recombinant inbred lines (RILs) revealed the quantitative trait loci (QTLs) associated with NopP interactions. A soybean genomic region containing two overlapping QTLs was analyzed in greater detail. A transcriptome analysis and qRT-PCR assay were used to identify candidate genes encoding proteins that interact with NopP. In some germplasms, NopP positively and negatively affected the NN and NDW, while NopP had different effects on NN and NDW in other germplasms. The QTL region in chromosome 12 was further analyzed. The expression patterns of candidate genes Glyma.12g031200 and Glyma.12g073000 were determined by qRT-PCR, and were confirmed to be influenced by NopP.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glycine max/genética , Glycine max/microbiologia , Sinorhizobium fredii/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Fenótipo , Locos de Características Quantitativas/genética , Nódulos Radiculares de Plantas/metabolismo
17.
RSC Adv ; 8(67): 38245-38258, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-35559087

RESUMO

This study reveals the first attempt to apply PTFE hollow fiber membranes for removing ultrafine particles in PM2.5. The asymmetric polytetrafluoroethylene (PTFE) hydrophobic hollow fiber membranes were prepared through a cold pressing method including paste extrusion, stretching and heating. The reduction ratio, stretching ratio and heating temperature have influences on the morphology, structure, porosity, shrinkage ratio, tensile strength and permeability of the PTFE hollow fiber membranes. The morphological properties of the PTFE hollow fiber membrane were studied using field emission scanning electron microscopy (FESEM). The increase of stretching ratio can improve the pore size and porosity of the hollow membrane, but be negative for the mechanical properties. By changing the reduction ratio we can obtain different inner diameter PTFE hollow fiber membranes. Finally, the PTFE hollow fiber membranes were tested for their performances in the removal of ultrafine particles in PM2.5. The PTFE hollow fiber membranes had the microstructure of nodes interconnected by fibrils, designed to possess the synergistic advantages of porous filters and fibrous filters with a sieve-like outer surface and a fibrous-like porous substrate. Under dead-end filtration, the filtration efficiency is related to the wall thickness, pore size and porosity of the membranes. The air filtration achieved was higher than 99.99% for PM2.5 and 90% for PM0.3, indicating that all the prepared PTFE hollow fiber membranes exhibited satisfactory removal of ultrafine particles performances. Because of the hydrophobicity, PTFE hollow fiber membranes have self-cleaning ability and a large dust-holding capacity of >120 g m-2, slowing down membrane fouling. The fouled filter media after washing retained a high filtration efficiency without obvious deterioration. The hydrophobic PTFE hollow fiber membranes developed in this work exhibited potential applications in air filtration.

18.
PLoS One ; 12(8): e0183026, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813484

RESUMO

Rett syndrome (RTT), a leading cause of intellectual disability in girls, is predominantly caused by mutations in the X-linked gene MECP2. Disruption of Mecp2 in mice recapitulates major features of RTT, including neurobehavioral abnormalities, which can be reversed by re-expression of normal Mecp2. Thus, there is reason to believe that RTT could be amenable to therapeutic intervention throughout the lifespan of patients after the onset of symptoms. A common feature underlying neuropsychiatric disorders, including RTT, is altered synaptic function in the brain. Here, we show that Mecp2tm1.1Jae/y mice display lower presynaptic function as assessed by paired pulse ratio, as well as decreased long term potentiation (LTP) at hippocampal Schaffer-collateral-CA1 synapses. Treatment of Mecp2tm1.1Jae/y mice with D-cycloserine (DCS), an FDA-approved analog of the amino acid D-alanine with antibiotic and glycinergic activity, corrected the presynaptic but not LTP deficit without affecting deficient hippocampal BDNF levels. DCS treatment did, however, partially restore lower BDNF levels in the brain stem and striatum. Thus, treatment with DCS may mitigate the severity of some of the neurobehavioral symptoms experienced by patients with Rett syndrome.


Assuntos
Ciclosserina/farmacologia , Síndrome de Rett/fisiopatologia , Transmissão Sináptica/efeitos dos fármacos , Animais , Apneia , Tronco Encefálico/metabolismo , Tronco Encefálico/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Ciclosserina/administração & dosagem , Modelos Animais de Doenças , Marcha/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Locomoção/efeitos dos fármacos , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Camundongos Transgênicos , Força Muscular/efeitos dos fármacos , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Tremor
19.
Clin Nucl Med ; 42(3): 231-234, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28033224

RESUMO

Despite increasing reliance on CT, MRI, and FDG PET/CT for oncological imaging, whole-body skeletal scintigraphy remains a frontline modality for staging and surveillance of osseous metastatic disease. We present a 54-year-old woman with metastatic breast cancer who received palliative external-beam radiation to the left ilium. Serial follow-up Tc-MDP bone scans demonstrated progressive soft-tissue uptake in her left lower extremity, extending from thigh to leg, with associated enlargement and skin thickening, consistent with lymphedema related to radiation-induced fibrosis. Correlative abdominopelvic CT scans confirmed fibrotic changes in the left thigh.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Linfedema/diagnóstico por imagem , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Feminino , Fibrose/diagnóstico por imagem , Fibrose/etiologia , Fluordesoxiglucose F18 , Humanos , Linfedema/etiologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Radioterapia/efeitos adversos , Medronato de Tecnécio Tc 99m
20.
J Comput Assist Tomogr ; 40(6): 872-879, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27454788

RESUMO

PURPOSE: To assess the ability of computed tomography (CT) to differentiate an atypical lipomatous tumor/well-differentiated liposarcoma (WDLPS) from a WDLPS with a dedifferentiated component (DDLPS) within it. MATERIALS AND METHODS: Forty-nine untreated patients with abdominal atypical lipomatous tumors/well-differentiated liposarcomas who had undergone contrast-enhanced CT were identified using an institutional database. Three radiologists who were blinded to the pathology findings evaluated all the images independently to determine whether a dedifferentiated component was present within the WDLPS. The CT images were evaluated for fat content (≤25% or >25%); presence of ground-glass density, enhancing and/or necrotic nodules; presence of a capsule surrounding the mass; septations; and presence and pattern of calcifications. A multivariate logistic regression model with generalized estimating equations was used to correlate imaging features with pathology findings. Kappa statistics were calculated to assess agreement between the three radiologists. RESULTS: On the basis of pathological findings, 12 patients had been diagnosed with DDLPS within a WDLPS and 37 had been diagnosed with WDLPS. The presence of an enhancing or a centrally necrotic nodule within the atypical lipomatous tumor was associated with dedifferentiated liposarcoma (P = 0.02 and P = 0.0003, respectively). The three readers showed almost perfect agreement in overall diagnosis (κ r = 0.83; 95% confidence interval, 0.67-0.99). CONCLUSIONS: An enhancing or centrally necrotic nodule may be indicative of a dedifferentiated component in well-differentiated liposarcoma. Ground-glass density nodules may not be indicative of dedifferentiation.


Assuntos
Neoplasias Abdominais/diagnóstico por imagem , Lipossarcoma/diagnóstico por imagem , Lipossarcoma/patologia , Radiografia Abdominal/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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