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1.
Chem Sci ; 15(25): 9557-9565, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939138

RESUMO

Sorption-based atmospheric water-harvesting (AWH) could help to solve global freshwater scarcity. The search for adsorbents with high water-uptake capacity at low relative humidity, rapid adsorption-desorption kinetics and high thermal conductivity is a critical challenge in AWH. Herein, we report a MAF-4 (aka ZIF-8)-derived nanoporous carbon (NPCMAF-4-800) with multiple N-doped sites, considerable micropore characteristics and inherent photothermal properties, for efficient water production in a relatively arid climate. NPCMAF-4-800 exhibited optimal water-sorption performance of 306 mg g-1 at 40% relative humidity (RH). An excellent sunlight-absorption rate was realized (97%) attributed to its high degree of graphitization. A proof-of-concept device was designed and investigated for the practical harvesting of water from the atmosphere using natural sunlight. NPCMAF-4-800 achieved an unprecedentedly high water production rate of 380 mg g-1 h-1 at 40% RH, and could produce 1.77 L kg-1 freshwater during daylight hours in an outdoor low-humidity climate of ∼25 °C and 40% RH. These findings may shed light on the potential of MOF-derived porous carbons in the AWH field, and inspire the future development of solar-driven water-generation systems.

2.
Int J Biol Macromol ; 256(Pt 2): 128579, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38048931

RESUMO

As a well-known natural and innocuous plant constituent, cellulose consists of abundant hydroxyl groups and can tightly adsorb onto material surfaces hydrogen bonding, resulting in a superhydrophilic surface. In this work, the hydrophobic polyvinylidene fluoride (PVDF) membranes were modified by immersing them in cellulose hydrogel using a simple one-step process. The modified PVDF membrane exhibited excellent resistance to fouling and oil adhesion, making it highly effective in separating various oil-in-water emulsions. The cellulose-modified PVDF membranes achieved a high oil rejection rate (>99 %) and a maximum separation flux of 2675.2 L·m-2·h-1. Furthermore, even an oil-in-water emulsion containing bovine serum albumin maintained a steady permeation flux after four filtration cycles. Additionally, these cellulose-modified PVDF membranes demonstrated excellent underwater superoleophobicity across a wide range of pH levels and high saline conditions. Overall, these cellulose-modified superhydrophilic PVDF membranes are sustainable, environmentally friendly, easily scalable, and hold great promise for practical applications in oily wastewater treatment.


Assuntos
Incrustação Biológica , Celulose , Polímeros de Fluorcarboneto , Polivinil , Celulose/química , Emulsões , Hidrogéis , Óleos
3.
Phytomedicine ; 120: 155032, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37611463

RESUMO

BACKGROUND: In recent years, Salvia miltiorrhiza and its active substances have remarkably progressed in treating central neurological disorders. Tanshinone IIA (TSA) is an active ingredient derived from the rhizome of Salvia miltiorrhiza that has been found to alleviate the symptoms of several psychiatric illnesses. Post-traumatic stress disorder (PTSD) is a mental disorder that results after experiencing a serious physical or psychological injury. The currently used drugs are not satisfactory for the treatment of PTSD. However, it has been reported that TSA can improve PTSD-like symptoms like learning and memory, cognitive disorder, and depression through multi-target regulation. PURPOSE: This paper discusses the ameliorative effects of TSA on PTSD-like symptoms and the possible mechanisms of action in terms of inhibition of neuronal apoptosis, anti-neuroinflammation, and anti-oxidative stress. Based on the pathological changes and clinical observations of PTSD, we hope to provide some reference for the clinical transformation of Chinese medicine in treating PTSD. METHODS: A large number of literatures on tanshinone in the treatment of neurological diseases and PTSD were retrieved from online electronic PubMed and Web of Science databases. CONCLUSION: TSA is a widely studied natural active ingredient against mental illness. This review will contribute to the future development of TSA as a new clinical candidate drug for improving PTSD-like symptoms.


Assuntos
Salvia miltiorrhiza , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Abietanos/farmacologia , Apoptose , Estresse Oxidativo
4.
Biochim Biophys Acta Mol Cell Res ; 1870(7): 119506, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37263298

RESUMO

Alternative pre-mRNA splicing, which produces various mRNA isoforms with distinct structures and functions from a single gene, is regulated by specific RNA-binding proteins and is an essential method for regulating gene expression in mammals. Recent studies have shown that abnormal change during neuronal development triggered by splicing mis-regulation is an important feature of various neurological diseases. Polypyrimidine tract binding protein 1 (PTBP1) is a kind of RNA-binding proteins with extensive biological functions. As a well-known splicing regulator, it affects the neuronal development process through its involvement in axon formation, synaptogenesis, and neuronal apoptosis, according to the most recent studies. Here, we summarized the mechanism of alternative splicing, structure and function of PTBP1, and the latest research progress on the role of alternative splicing events regulated by PTBP1 in axon formation, synaptogenesis and neuronal apoptosis, to reveal the mechanism of PTBP1-regulated changes in neuronal development process.


Assuntos
Doenças do Sistema Nervoso , Neurogênese , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA , Animais , Mamíferos/genética , Mamíferos/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA/metabolismo , Splicing de RNA , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Doenças do Sistema Nervoso/genética , Neurogênese/genética
5.
J Drug Target ; 31(7): 685-692, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37358358

RESUMO

Mitochondria are a crucial energy source for maintaining neuronal growth and synaptic function. Neurons possess unique morphological characteristics, which make the proper regulation of mitochondrial transport essential for meeting their energy demands. Syntaphilin (SNPH) is capable of specifically targeting the outer membrane of axonal mitochondria, anchoring them to microtubules, and thereby preventing their transport. SNPH also interacts with other mitochondrial proteins to regulate mitochondrial transport. The regulation of mitochondrial transport and anchoring mediated by SNPH is indispensable for axonal growth during neuronal development, maintenance of ATP levels during neuronal synaptic activity, and regeneration of mature neurons following damage. Precise blocking of SNPH may be an effective therapeutic strategy for neurodegenerative diseases and related mental disorders.


Assuntos
Proteínas Associadas aos Microtúbulos , Doenças Neurodegenerativas , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Axônios/metabolismo , Neurônios/metabolismo , Mitocôndrias/metabolismo
6.
Wiley Interdiscip Rev RNA ; 14(2): e1740, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35574699

RESUMO

Central nervous system injury diseases can cause the loss of many neurons, and it is difficult to regenerate. The field of regenerative medicine believes that supplementing the missing neurons may be an ideal method for nerve injury repair. Recent studies have found that down-regulation of polypyrimidine tract binding protein 1 (PTBP1) expression can make glial cells transdifferentiate into different types of neurons, which is expected to be an alternative therapy to restore neuronal function. This article summarized the research progress on the structure and biological function of the PTBP family, the mutual regulation of PTBP1 and PTBP2, their role in neurogenesis, and the latest research progress in targeting PTBP1 to mediate the transdifferentiation of glial cells into neurons, which may provide some new strategies and new ideas for the future treatment of central nervous system injury and neurodegenerative diseases. This article is categorized under: RNA Processing > Splicing Regulation/Alternative Splicing.


Assuntos
Transdiferenciação Celular , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Fatores de Processamento de RNA/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Neurônios/metabolismo , Processamento Alternativo , Neuroglia/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo
7.
Int J Biol Macromol ; 229: 247-259, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36529225

RESUMO

Risk-stratification of acute myeloid leukemia (AML) based on (cyto)genetic aberrations, including hotspot mutations, deletions and point mutations have evolved substantially in recent years. With the development of next-generation sequence technology, more and more novel mutations in the AML were identified. Thus, to unravel roles and mechanism of novel mutations would improve prognostic and predictive abilities. In this study, two novel germline JAK2 His608Tyr (H608Y) and His608Asn (H608N) mutations were identified and the molecular basis of these mutations in the leukemiagenesis of AML was elucidated. Our results indicated that JAK2 H608Y and H608N mutations disrupted the hydrogen bond between Q656 and H608 which reduced the JH2 domain's activity and abolished interactions between JH1 and JH2 domains, forced JAK2 into the active conformation, facilitated the entrance of substrates and thus caused JAK2 hyperactivation. Further studies suggested that JAK2 H608Y and H608N mutations enhanced the cell proliferation and inhibited the differentiation of Ba/F3 and MV4-11 cells via activating the JAK2-STAT5 signaling pathway. Moreover, rescue experiments demonstrated that mutations repaired the hydrogen bond between Q656 and H608 displayed opposite results. Thus, this study revealed the molecular basis of JAK2 H608Y and H608N mutations in the pathology of AML.


Assuntos
Janus Quinase 2 , Leucemia Mieloide Aguda , Humanos , Janus Quinase 2/metabolismo , Mutação , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proliferação de Células/genética , Transdução de Sinais/genética , Diferenciação Celular
8.
Neuropharmacology ; 224: 109365, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36462635

RESUMO

Abscisic acid (ABA), a conserved hormone existing in plants and animals, not only regulates blood glucose and inflammation but also has good therapeutic effects on obesity, diabetes, atherosclerosis and inflammatory diseases in animals. Studies have shown that exogenous ABA can pass the blood-brain barrier and inhibit neuroinflammation, promote neurogenesis, enhance synaptic plasticity, improve learning, memory and cognitive ability in the central nervous system. At the same time, ABA plays a crucial role in significant improvement of Alzheimer's disease, depression, and anxiety. Here we review the previous research progress of ABA on the physiological effects and clinical application in the related diseases. By summarizing the biological functions of ABA, we aim to reveal the possible mechanisms of ameliorative function of ABA on learning and memory, to provide a theoretical basis that ABA as a novel and safe drug improves learning memory and cognitive impairment in central system diseases such as aging, neurodegenerative diseases and traumatic brain injury.


Assuntos
Ácido Abscísico , Doença de Alzheimer , Animais , Ácido Abscísico/farmacologia , Aprendizagem , Cognição
9.
Front Genet ; 13: 898474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051696

RESUMO

Polo-like kinase 4 (PLK4), a key regulator of centriole biogenesis, is frequently overexpressed in cancer cells. However, roles and the mechanism of PLK4 in the leukemiagenesis of acute myeloid leukemia (AML) remain unclear. In this study, the PLK4 inhibitor Centrinone and the shRNA knockdown were used to investigate roles and the mechanism of PLK4 in the leukemiagenesis of AML. Our results indicated that Centrinone inhibited the proliferation of AML cells in a dose- and time-dependent manner via reduced the expression of PLK4 both in the protein and mRNA levels. Moreover, colony formation assay revealed that Centrinone reduced the number and the size of the AML colonies. Centrinone induced AML cell apoptosis by increasing the activation of Caspase-3/poly ADP-ribose polymerase (PARP). Notably, Centrinone caused the G2/M phase cell cycle arrest by decreasing the expression of cell cycle-related proteins such as Cyclin A2, Cyclin B1, and Cyclin-dependent kinase 1 (CDK1). Consistent with above results, knockdown the expression of PLK4 also inhibited cell proliferation and colony formation, induced cell apoptosis, and caused G2/M phase cell cycle arrest without affecting cell differentiation. All in all, this study suggested that PLK4 inhibited the progression of AML in vitro, and these results herein may provide clues in roles of PLK4 in the leukemiagenesis of AML.

10.
Cell Oncol (Dordr) ; 45(5): 1005-1018, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36036884

RESUMO

PURPOSE: FLT3 mutations occurred in approximately one third of patients with acute myeloid leukemia (AML). FLT3-ITD mutations caused the constitutive activation of the RAS/MAPK signaling pathway. Ribosomal S6 Kinases (RSKs) were serine/threonine kinases that function downstream of the Ras/Raf/MEK/ERK signaling pathway. However, roles and mechanisms of RSKs inhibitor LJH-685, and combinational effects of LJH-685 and FLT3 inhibitor FF-10101 on AML cells were till unclear. METHODS: Cell viability assay, CFSE assay, RT-qPCR, Colony formation assay, PI stain, Annexin-V/7-AAD double stain, Western blot, and Xenogeneic transplantation methods were used to used to investigate roles and mechanisms of LJH-685 in the leukemogenesis of AML. RESULTS: LJH-685 inhibited the proliferation and clone formation of AML cells, caused cell cycle arrest and induced the apoptosis of AML cells via inhibiting the RSK-YB-1 signaling pathway. MV4-11 and MOLM-13 cells carrying FLT3-ITD mutations were more sensitive to LJH-685 than that of other AML cell lines. Further studies suggested that LJH-685 combined with Daunorubicin or FF- 10101 synergistically inhibited the cell viability, promoted the apoptosis and caused cycle arrest of AML cells carrying FLT3-ITD mutations. Moreover, in vivo experiments also indicated that LJH-685 combined with FF-10101 or Daunorubicin prolonged the survival time of NSG mice and reduced the leukemogenesis of AML. CONCLUSION: Thus, these observations demonstrated combination of RSK inhibitor LJH-685 and FLT3 inhibitor FF-10101 showed synergism anti-leukemia effects in AML cell lines with FLT3-ITD mutations via inhibiting MAPK-RSKs-YB-1 pathway and provided new targets for therapeutic intervention especially for AML with FLT3-ITD mutations and Daunorubicin-resistant AML.


Assuntos
Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Animais , Camundongos , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Daunorrubicina/farmacologia , Daunorrubicina/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
11.
Front Chem ; 10: 970033, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034660

RESUMO

In this work, a dispersible graphene-based material with a characteristic of aggregation-induced emission (AIE) was prepared by wet chemical reduction of graphene oxide (GO). During the GO reduction process, a conjugated molecule TPEP containing tetraphenylethylene (TPE) and pyrene was employed as a stabilizer because of the π-π interactions and the wrapping effect. The as-prepared rGO-TPEP not only has good dispersion in solution but also processes the AIE feature. Its fluorescence intensity is 2.23 times higher than that of TPEP at the same condition. The unique optical properties and AIE effect enable the rGO-TPEP as a chemical sensor for highly sensitive explosive detection in aggregated state and solid state. In the aggregated state, trace 2,4-dinitrotoluene (DNT) can be detected by the rGO-TPEP even when the concentration is as low as 0.91 ppm, and the quenching constant is as high as 2.47 × 104 M-1.

12.
Photodiagnosis Photodyn Ther ; 39: 102986, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35760351

RESUMO

We report the case of a 20-year-old man with acne conglobata (AC) who was treated with 5-aminolevulinic acid photodynamic therapy (ALA-PDT) sequentially to deroofing, and finally used fractional carbon dioxide laser for esthetic requirements, achieving satisfying results. AC is a severe form of acne vulgaris that can lead to significant scarring and has serious negative effects on a patient's psychological well-being and quality of life. Some cases are likely resistant to currently available treatments. This report describes a promising, and effective method for the treatment of AC.


Assuntos
Acne Conglobata , Acne Vulgar , Fotoquimioterapia , Acne Conglobata/tratamento farmacológico , Acne Vulgar/tratamento farmacológico , Adulto , Ácido Aminolevulínico/uso terapêutico , Humanos , Masculino , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
13.
Ying Yong Sheng Tai Xue Bao ; 33(6): 1539-1546, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35729131

RESUMO

The distribution pattern of forest fuel loading is driven by the interaction of environmental factors, such as terrain and vegetation. Based on field sampling data of surface dead fuels of seven main forest types in southern Jiangxi Province, and according to the classification standard of different time-lags, we constructed structural equation models to explore the relationship between surface fuel loadings and environmental factors such as terrain and vegetation etc. We analyzed the influence path of each factor and its direct, indirect, and total influence. The results showed that the coniferous and broad-leaved mixed forest had the highest loadings and the Phyllostachys heterocycla pure forest had the lowest loadings for all the 1, 10, and 100 h time-lag fuels. The influencing coefficient of environmental factors for 1 h time-lag fuels were ranked as: slope (0.40) > crown height (0.07) > tree species (-0.03) > canopy closure (0.01). For the 10 h time-lag fuels, the environmental factors were ranked as: diameter at breast height (0.15) >tree species (-0.09) > aspect (-0.08) > canopy closure (-0.06). For the 100 h time-lag fuels, the environmental factors were ranked as: aspect (0.25) > diameter at breast height (0.19) > canopy closure (-0.08) > tree species (0.02). The influencing coefficient of environmental factors for the total fuels were ranked as: slope (0.22) > tree species (-0.04), canopy closure (-0.04) > crown height (-0.01).


Assuntos
Florestas , Traqueófitas , China , Modelos Teóricos , Árvores
14.
Membranes (Basel) ; 12(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35448382

RESUMO

A porous substrate plays an important role in constructing a thin-film composite forward osmosis (TFC-FO) membrane. To date, the morphology and performance of TFC-FO membranes are greatly limited by porous substrates, which are commonly fabricated by non-solvent induced phase separation (NIPS) or thermally induced phase separation (TIPS) processes. Herein, a novel TFC-FO membrane has been successfully fabricated by using cellulose triacetate (CTA) porous substrates, which are prepared using a nonsolvent-thermally induced phase separation (N-TIPS) process. The pore structure, permeability, and mechanical properties of CTA porous substrate are carefully investigated via N-TIPS process (CTAN-TIPS). As compared with those via NIPS and TIPS processes, the CTAN-TIPS substrate shows a smooth surface and a cross section combining interconnected pores and finger-like macropores, resulting in the largest water flux and best mechanical property. After interfacial polymerization, the obtained TFC-FO membranes are characterized in terms of their morphology and intrinsic transport properties. It is found that the TFC-FO membrane supported by CTAN-TIPS substrate presents a thin polyamide film full of nodular and worm-like structure, which endows the FO membrane with high water permeability and selectivity. Moreover, the TFC-FO membrane supported by CTAN-TIPS substrate displays a low internal concentration polarization effect. This work proposes a new insight into preparing TFC-FO membrane with good overall performance.

15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1203-1208, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362503

RESUMO

OBJECTIVE: To investigate the relationship between the levels of ferritin, C-reactive protein (CRP), lactate dehydrogenase (LDH) and interleukin-6 (IL-6) in peripheral serum and cytokine release syndrome (CRS) in patients with relapse and/or refractory multiple myeloma (R/R MM) after receiving chimeric antigen receptor T cells (CAR-T) immunotherapy. METHODS: Twenty-eight patients with R/R MM were treated with 1×106/kg humanized CD19 CAR-T and mouse B cell maturation antigen CAR-T cells after pretreatment chemotherapy based on fludarabine and cyclophosphamide. The concentrations of ferritin, CRP, LDH, and IL-6 in peripheral blood were measured regularly within 30 days after infusion, and the correlation between severity of CRS and above indexes was analyzed. RESULTS: Among the 28 patients, 27 cases (96.4%) developed CRS, 24 cases (85.7%) in 1-2 grade CRS and 3 cases (10.7%) in 3-5 grade. The severity grade of CRS of 27 patients was positively correlated with the peak values of ferritin, CRP, LDH, and IL-6 in peripheral blood (r1=0.511, r2=0.375, r3=0.480, r4=0.632). The median peak values of ferritin, CRP, LDH and IL-6 in peripheral serum of patients with grade 3-5 CRS were significantly higher than those in patients with grade 0-2 CRS. CONCLUSION: After receiving CAR-T cellular immunotherapy, the incidence of CRS in patients with R/R MM is higher, but most of them are in grade 1 or 2. The severity of CRS is positively correlated with the levels of ferritin, CRP, LDH and IL-6 in peripheral blood.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Animais , Antígenos CD19 , Síndrome da Liberação de Citocina , Humanos , Imunoterapia Adotiva , Camundongos , Mieloma Múltiplo/terapia , Recidiva Local de Neoplasia
16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1464-1467, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067938

RESUMO

OBJECTIVE: To investigate the prognostic significance of CUEDC1 in patients with acute myeloid leukemia (non-M3). METHODS: 52 cases newly diagnosed AML (non-M3) were selected and enrolled in AML non-M3 group, at the same time, 10 cases of iron doficiency anemia were selected and enrolled in control group. The bone marrow mononuclear cells(BMMC) were isolated from bone marrow of patients, the expression level of CUEDC1 in BMMC was detected by RT-PCR, the expression level of CUEDC1 mRNA in BMMC of AML-subtype patients was compared. The AML patients were divided into low and high expression groups according to the expression level of CUEDC1 mRNA, and the complete remission rate after the first chemothrapy course was compared, and the relative expression level of CUEDC1 mRNA between the remission and the non-remission group were compared. RESULTS: CUEDC1 was expressed in BMMC of 52 newly diagnosed patients with AML (non-M3) of all subtypes, which was higher than that in control group (P<0.05), and the expression level of CUEDC1 mRNA in M5 patients was the highest (P<0.05). In CUEDC1 low expression group, induced complete remisson rate (76.2%,16/21) after the first course of treatment seemed higher than that of the high expression group(67.7%,21/31), but the difference was not statistically significant; the expression level of CUEDC1 mRNA in the remission group of patients with newly diagnosed AML(non-M3) was lower than that in the non-remission group(P<0.05). CONCLUSION: CUEDC1 is highly expressed in newly diagnosed patients with AML, among which the CUEDC1 mRNA expression level in M5 patients is the highest, the expression of CUEDC1 mRNA possibly relates to the prognosis of patients with AML.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda , Medula Óssea , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ferro , Prognóstico , RNA Mensageiro/genética
17.
Polymers (Basel) ; 11(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683573

RESUMO

Lignin is the second most abundant and low-cost natural polymer, but its high value-added utilization is still lack of effective and economic ways. In this paper, waste lignosulfonate (LS) was introduced to fabricate antifouling membrane surfaces via layer-by-layer self-assembly with polyethyleneimine (PEI). The LS/PEI multilayers were successfully deposited on the polysulfone (PSf) membrane, as demonstrated by ATR-FTIR, XPS, Zeta potential measurements, AFM, and SEM. Meanwhile, the effect of the number of bilayers was investigated in detail on the composition, morphologies, hydrophilicity, and antifouling performance of the membrane surface. As a result, with the bilayer numbers increase to 5, the PSf membrane shows smooth surface with small roughness, and its water contact angle reduces to 44.1°, indicating the improved hydrophilicity. Accordingly, the modified PSf membrane with 5 LS/PEI bilayers repels the adsorption of protein, resulting in good antifouling performance. This work provides a green, facile, and low-cost strategy to construct antifouling membrane surfaces.

18.
Int J Biol Macromol ; 137: 1030-1040, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31299252

RESUMO

Activating mutations in JAK2 have been described in patients with various hematologic malignancies including acute myeloid leukemia (AML) and myeloproliferative neoplasms. However, mechanism of these mutations in JAK2's activity, structural stability and pathology of AML remains poorly understood. The JAK2 T875N somatic mutation has been detected in about 5.2% of AML patients. But the structural basis and mechanism of JAK2 T875N mutation in the pathology of AML is still unclear. Our results suggested that JAK2 T875N mutation disrupted the T875 and D873 interaction which destroyed the compact structure of JH1 domain, forced it into the active conformation, facilitated the entrance of substrate and thus led to JAK2 hyperactivation. Mutations (T875N, T875A, D873A and D873G) disrupted the T875 and D873 interaction enhanced JAK2's activity, decreased its structural stability and JH2 domain's activity which further enhanced JAK2's activity, while mutations (T875R, D873E, T875R/D873E) repaired this interaction displayed opposite results. Moreover, JAK2 T875N mutation enhanced the activity of JAK2-STAT5 pathway, promoted the proliferation and transformation of OCI-AML3 cells. This study provides clues in understanding structural basis of T875N mutation caused JAK2 hyperactivation and its roles in the pathology of AML.


Assuntos
Transformação Celular Neoplásica/genética , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mieloide Aguda/patologia , Mutação , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ativação Enzimática/genética , Estabilidade Enzimática/genética , Humanos , Janus Quinase 2/química , Modelos Moleculares , Conformação Proteica
19.
Int J Biol Macromol ; 136: 209-219, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31199972

RESUMO

Janus tyrosine kinase 2 (JAK2) mediates downstream signaling of cytokine receptors in all hematological lineages, constitutively active somatic JAK2 mutations were important for the leukemogenesis of acute leukemia (AL). The JAK2 R867Q somatic mutation is detected in a subset of AL patients. However, roles of JAK2 R867Q mutation in the pathogenesis of AL remain unclear. In this study, homology modeling analysis showed that loss of interaction between R867 and Y613 disrupted the JAK2 JH1/JH2 domain's interactions was responsible for its activation. JAK2 R867Q and mutations (R867A and R867G) abolished this interaction caused JAK2 constitutive activation. While, mutations (R867K, Y613E, R867K/Y613E) repairing this interaction reduced JAK2 R867Q mutation's activity. Furthermore, our studies showed that abolished R867 and Y613 interaction disrupted JH1/JH2 domains' interactions and led to JAK2 constitutive activation. More importantly, mutations (R867Q, R867A and R867G) disrupted this interaction enhanced the activity of JAK2-STAT5 pathway and the proliferation of Ba/F3 and MV4-11 cells. Further study showed that JAK2 R867Q mutation promoted the expression of proliferation marker and inhibited the differentiation marker of Ba/F3 and MV4-11 cells. Thus our studies provide clues in understanding the pathogenesis of JAK2 R867Q mutation in AL.


Assuntos
Janus Quinase 2/química , Janus Quinase 2/metabolismo , Leucemia/genética , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutação , Doença Aguda , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Humanos , Interleucina-3/farmacologia , Janus Quinase 2/genética , Leucemia/patologia , Modelos Moleculares , Proteínas Mutantes/genética , Redobramento de Proteína , Estrutura Secundária de Proteína/genética , Estrutura Terciária de Proteína/genética
20.
Polymers (Basel) ; 11(5)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091763

RESUMO

Nanocomposite membranes are strongly desired to break a trade-off between permeability and selectivity. This work reports new thin film nanocomposite (TFN) forward osmosis (FO) membranes by embedding aluminosilicate nanotubes (ANTs) into a polyamide (PA) rejection layer. The surface morphology and structure of the TFN FO membranes were carefully characterized by FTIR, XPS, FESEM and AFM. The ANTs incorporated PA rejection layers exhibited many open and broad "leaf-like" folds with "ridge-and-valley" structures, high surface roughness and relatively low cross-linking degree. Compared with thin film composite (TFC) membrane without ANTs, the TFN membrane with only 0.2 w/v% ANTs loading presented significantly improved FO water permeability, selectivity and reduced structural parameters. This promising performance can be mainly contributed to the special ANTs embedded PA rejection layer, where water molecules preferentially transport through the nanochannels of ANTs. Molecular dynamic simulation further proved that water molecules have much larger flux through the nanotubes of ANTs than sodium and chloride ions, which are attributed to the intrinsic hydrophilicity of ANTs and low external force for water transport. This work shows that these TFN FO membranes with ANTs decorated PA layer are promising in desalination applications due to their simultaneously enhanced permeability and selectivity.

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