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1.
Carbohydr Polym ; 334: 122016, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553203

RESUMO

This paper reports an environment-friendly biobased foam made with cellulose nanofiber (CNF) and a biobased hyperbranched crosslinker, glycerol succinic anhydride (GSA). As a biobased hyperbranched crosslinker, carboxyl-terminated GSA is synthesized through a straightforward esterification process involving glycerol and succinic anhydride. The GSA-crosslinked CNF (GSA/CNF) foam is prepared using a facile, sustainable, cost-effective, and efficient solvent-exchange method. The resulting foam exhibits notable characteristics, including improved dimensional stability, remarkably low density (13.41 mg/cm3) with high porosity (>99 %), and exceptional compressive strength (494 kPa) and modulus (452 kPa). Further, the foam offers outstanding sound absorption capabilities with a coefficient of 0.986 at 2 kHz and remarkably low thermal conductivity (30.18 mW/mK), significantly lower than commonly used and reported porous materials, indicating its potential as an efficient, environmentally friendly sound absorption and thermal insulation material.

2.
Heliyon ; 10(3): e25272, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38327421

RESUMO

With the increased demand for biobased epoxy thermosets as an alternative to petroleum-based materials in various fields, developing environment-friendly and high-performance natural fiber-biobased epoxy nanocomposites is crucial for industrial applications. Herein, an environment-friendly nanocomposite is reported by introducing cellulose nanofiber (CNF) in situ interaction with lignin-derived vanillin epoxy (VE) monomer and 4, 4´-diaminodiphenyl methane (DDM) hardener that serves as a multifunctional platform. The CNF-VE nanocomposite is fabricated by simply dispersing the CNF suspension to the VE and DDM hardener solution through the in-situ reaction, and its mechanical properties and thermal insulation behavior, wettability, chemical resistance, and optical properties are evaluated with the CNF weight percent variation. The well-dispersed CNF-VE nanocomposite exhibited high tensile strength (∼127.78 ± 3.99 MPa) and strain-at-break (∼16.49 ± 0.61 %), haziness (∼50 %) and UV-shielding properties. The in situ loading of CNF forms covalent crosslinking with the VE and favors improving the mechanical properties along with the homogeneous dispersion of CNF. The CNF-VE nanocomposite also shows lower thermal conductivity (0.26 Wm-1K-1) than glass. The environment-friendly and high-performance nanocomposite provides multiple platforms and can be used for building materials.

3.
Virchows Arch ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388965

RESUMO

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. While induction chemotherapy leads to remission in most patients, a significant number will experience relapse. Therefore, there is a need for novel therapies that can improve remission rates in patients with relapsed and refractory AML. CD70 is the natural ligand for CD27 (a member of the TNF superfamily) and appears to be a promising therapeutic target. Consequently, there is considerable interest in developing chimeric antigen receptor (CAR) T-cell therapy products that can specifically target CD70 in various neoplasms, including AML. In this study, we employed routine diagnostic techniques, such as immunohistochemistry and flow cytometry, to investigate the expression of CD70 in bone marrow samples from treatment-naïve and relapsed AML patients after hypomethylating agents (HMA). Also, we evaluated the impact of HMA on CD70 expression and examined CD70 expression in various leukemic cell subsets and normal hematopoietic progenitors.

4.
Gels ; 10(1)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38247784

RESUMO

In recent years, stimuli-responsive nanogels that can undergo suitable transitions under endogenous (e.g., pH, enzymes and reduction) or exogenous stimuli (e.g., temperature, light, and magnetic fields) for on-demand drug delivery, have received significant interest in biomedical fields, including drug delivery, tissue engineering, wound healing, and gene therapy due to their unique environment-sensitive properties. Furthermore, these nanogels have become very popular due to some of their special properties such as good hydrophilicity, high drug loading efficiency, flexibility, and excellent biocompatibility and biodegradability. In this article, the authors discuss current developments in the synthesis, properties, and biomedical applications of stimulus-responsive nanogels. In addition, the opportunities and challenges of nanogels for biomedical applications are also briefly predicted.

5.
Int J Biol Macromol ; 260(Pt 2): 129370, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218281

RESUMO

Strong, tough and sustainable materials are in high demand in various engineering applications. We demonstrate a potential sustainable hybrid film made from natural cellulose and a biobased slurry. Through a simple and scalable approach, cellulose can be processed into an advanced material with over 2.8 and 9.2-fold increase in dry strength and toughness after curing and a 728-fold increase in wet strength, respectively. In addition, these hybrid composite films display an outstanding antioxidant activity surpassing 90 %, along with excellent ultraviolet radiation shielding and thermal insulation properties. Further, the hybrid films can be fabricated by integrating all-natural materials and still guarantee their unique functionality. We also demonstrate the feasibility of a circular bioeconomy by recycling the hybrid film using a green, deep eutectic solvent to fabricate a recycled hybrid film that displays excellent mechanical and optical properties. When recycling is unsuitable or economical, the hybrid film can naturally degrade in the soil under 6 months. These encouraging findings suggest the promise of cellulose hybrid films as a renewable, low-cost, tough, and strong material with the potential to replace nonrenewable synthetic plastics and products.


Assuntos
Celulose , Raios Ultravioleta , Materiais Dentários , Engenharia , Plásticos
6.
Leukemia ; 38(1): 82-95, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38007585

RESUMO

We identified activin A receptor type I (ACVR1), a member of the TGF-ß superfamily, as a factor favoring acute myeloid leukemia (AML) growth and a new potential therapeutic target. ACVR1 is overexpressed in FLT3-mutated AML and inhibition of ACVR1 expression sensitized AML cells to FLT3 inhibitors. We developed a novel ACVR1 inhibitor, TP-0184, which selectively caused growth arrest in FLT3-mutated AML cell lines. Molecular docking and in vitro kinase assays revealed that TP-0184 binds to both ACVR1 and FLT3 with high affinity and inhibits FLT3/ACVR1 downstream signaling. Treatment with TP-0184 or in combination with BCL2 inhibitor, venetoclax dramatically inhibited leukemia growth in FLT3-mutated AML cell lines and patient-derived xenograft models in a dose-dependent manner. These findings suggest that ACVR1 is a novel biomarker and plays a role in AML resistance to FLT3 inhibitors and that FLT3/ACVR1 dual inhibitor TP-0184 is a novel potential therapeutic tool for AML with FLT3 mutations.


Assuntos
Leucemia Mieloide Aguda , Humanos , Simulação de Acoplamento Molecular , Mutação , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/uso terapêutico , Apoptose , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/uso terapêutico
7.
Int J Biol Macromol ; 256(Pt 2): 128411, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016604

RESUMO

The development of high-strength and intrinsic flame-retardant natural fiber-reinforced green composite (NFRGC) is a landmark for high-performance structural applications. This paper reports a biobased, high-performance, flame-retardant composite material based on diverse bio-resources. Tough and strong cellulose long filaments (CLFs) are combined with vanillin-derived epoxy (VDE) resin to achieve high strength and flame-retardant NFRGC. The green composite was fabricated using a simple hand lay-up and compression molding technique. The green composite showed a noteworthy increment of 100.9 % flexural strength and 346 % flexural modulus compared to the neat VDE resin. Interestingly, despite the highly flammable nature of CLF, the green composite passes a V-0 rating under the UL-94 test, indicating excellent flame-retardant characteristics. Additionally, the green composite demonstrated outstanding hydrophobicity with a water contact angle of 104.2° and good chemical stability in various acidic and organic solvents. The green composite's excellent mechanical and physical properties show its potential for high-strength and flame-retardant structural applications.


Assuntos
Celulose , Retardadores de Chama , Benzaldeídos , Citoesqueleto , Resinas Epóxi
8.
Polymers (Basel) ; 15(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36904466

RESUMO

Aiming to generate wealth from waste and due to their significant fire threats to forests and their rich cellulose content, lignocellulosic pine needle fibers (PNFs) are utilized in this study as a reinforcement of the thermoplastic elastomer styrene ethylene butylene styrene (SEBS) matrix to create environmentally friendly and economical PNF/SEBS composites using a maleic anhydride-grafted SEBS compatibilizer. The chemical interaction in the composites studied by FTIR shows that strong ester bonds are formed between reinforcing PNF, the compatibilizer, and the SEBS polymer, leading to strong interfacial adhesion between the PNF and SEBS in the composites. This strong adhesion in the composite exhibits higher mechanical properties than the matrix polymer indicating a 1150 % higher modulus and a 50 % higher strength relative to the matrix. Further, the SEM pictures of the tensile-fractured samples of the composites validate this strong interface. Finally, the prepared composites show better dynamic mechanical behavior indicating higher storage and loss moduli and Tg than the matrix polymer suggesting their potential for engineering applications.

9.
Polymers (Basel) ; 15(3)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36771874

RESUMO

In this study, a graphene oxide/cellulose composite (GO-cellulose) was prepared usingcellulose and graphene oxide (GO) through ultrasonication, followed by the freeze-dried method. The Brunauer-Emmett-Teller (BET) specific surface area of GO-cellulose (~6.042 m2/g) was higher compared to cellulose (1.023 m2/g).The UV-Visible spectraindicated that the prepared GO-cellulose composite removedphenol efficiently from aqueous solutions with high adsorption power. The effectiveness of the composite for phenol adsorption was examinedunder diverse conditions.The results reveal that the composite optimally improved the adsorption at pH 7 with a dose of 0.125 g/30 L in about 40 min. The adsorption process showed that in optimum conditions, 86 ± 2% of phenol was removed in 40 min with an adsorption capacity of 6.192 mg g-1. The adsorption behavior was well fitted to the pseudo-second-order kinetic model and the Langmuir isotherms at all temperatures.The present study suggests that synthesized GO-cellulose is useful inthe removal of phenol pollutants from aqueous solutions.

10.
Ortop Traumatol Rehabil ; 24(5): 305-309, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36524779

RESUMO

BACKGROUND: Femoral neck fractures are intracapsular hip fractures. There are several surgical implants that have been used to treat femoral neck fractures. Depuy Synthes Products and the lower extremity expert group have developed an innovative femoral neck system (FNS) for fixing femoral neck fractures. With minimally invasive procedures, FNS can provide angular stability. MATERIALS AND METHODS: A non-randomized single centre prospective study was conducted in 30 patients of less than 60 years of age at Maharishi Markandeshwar Institute of Medical Sciences and Research between August 2020 to May 2022. All patients underwent internal fixation with FNS within 48 hours of presentation. RESULTS: Although blood loss and operative time in our operated group was more than that in conventional fixation by cannulated screws, our group had better VAS scores, better Harris scores and lower complication rates. CONCLUSIONS: 1. The Femoral Neck System resulted in better biomechanical properties and good early results in femoral neck fractures. FNS gives both angular stability and rotational stability. The last follow-up in our study showed Harris score to be significantly higher, and the incidence of complications were lower. 2. The combination of FNS bolts with anti-rotation screws avoids the "Z" effect and improves the overall stability and anti-rotation effect. 3. In addition, the novel sliding compression mechanism of FNS allows the fracture ends to come in close contact with each other, benefitting fracture healing.


Assuntos
Fraturas do Colo Femoral , Colo do Fêmur , Humanos , Parafusos Ósseos , Estudos Prospectivos , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos , Resultado do Tratamento
11.
Ortop Traumatol Rehabil ; 24(5): 319-323, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36524782

RESUMO

BACKGROUND: Intracapsular femoral neck fractures can result from trivial trauma in the elderly or high-energy trauma in younger age-groups. In younger patients aged <60 years, the femoral head should be conserved to avoid the long-term complications of replacement arthroplasty. The options of osteosynthesis include closed/ open reduction and internal fixation with/without bone grafting. Internal fixation alone does not provide rigid fixation, owing to cavities in the posterior part of the femoral head and neck. Fibular grafts augment union and provide strength to the posterior cortex during reconstruction of the femoral neck. We evaluated the use of fibular grafting for fresh femoral neck fractures with posterior comminution. MATERIAL AND METHODS: Between November 2019 and March 2022, 20 women and 12 men aged 20 to 60 years underwent osteosynthesis and fibular strut grafting supplemented with 7.0-mm cannulated hip screws for Garden grades III (n=19) and IV (n=13) femoral neck fractures. Clinical and radiological outcomes were evaluated. RESULTS: Patients were followed up for a period of 15 months. According to the Harris hip score, outcome was good to excellent in 23, fair in 7, and poor in 2. 30 of the 32 patients achieved bone union after a mean of 4.5 (range 3.5-5.5) months. In 2 patients, the bone was united with a mean of 10º of varus collapse. Two patients had non-union. Other complications included screw migration in the joint space (n=1) and screw pullout (n=2). No patient had avascular necrosis of the femoral head. CONCLUSION: Fixation with cancellous screws and fibular strut grafts for femoral neck fractures is cost-effective and technically less demanding, and associated with good outcomes.


Assuntos
Fraturas do Colo Femoral , Fraturas Cominutivas , Masculino , Idoso , Humanos , Feminino , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Fíbula/cirurgia , Fixação Interna de Fraturas , Fraturas Cominutivas/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
12.
Front Immunol ; 13: 1018047, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203567

RESUMO

The current global platelet supply is often insufficient to meet all the transfusion needs of patients, in particular for those with alloimmune thrombocytopenia. To address this issue, we have developed a strategy employing a combination of approaches to achieve more efficient production of functional megakaryocytes (MKs) and platelets collected from cord blood (CB)-derived CD34+ hematopoietic cells. This strategy is based on ex-vivo expansion and differentiation of MKs in the presence of bone marrow niche-mimicking mesenchymal stem cells (MSCs), together with two other key components: (1) To enhance MK polyploidization, we used the potent pharmacological Rho-associated coiled-coil kinase (ROCK) inhibitor, KD045, resulting in liberation of increased numbers of functional platelets both in-vitro and in-vivo; (2) To evade HLA class I T-cell-driven killing of these expanded MKs, we employed CRISPR-Cas9-mediated ß-2 microglobulin (ß2M) gene knockout (KO). We found that coculturing with MSCs and MK-lineage-specific cytokines significantly increased MK expansion. This was further increased by ROCK inhibition, which induced MK polyploidization and platelet production. Additionally, ex-vivo treatment of MKs with KD045 resulted in significantly higher levels of engraftment and donor chimerism in a mouse model of thrombocytopenia. Finally, ß2M KO allowed MKs to evade killing by allogeneic T-cells. Overall, our approaches offer a novel, readily translatable roadmap for producing adult donor-independent platelet products for a variety of clinical indications.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Trombocitopenia , Animais , Citocinas/farmacologia , Sangue Fetal , Megacariócitos , Camundongos , Linfócitos T , Quinases Associadas a rho
13.
Int J Biol Macromol ; 222(Pt A): 1304-1313, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36198365

RESUMO

This paper reports a bio-based vanillin-derived epoxy (VDE) resin for bio-based natural fiber-reinforced composites. VDE monomer was synthesized, and curing agents, namely, 4,4´-diaminodiphenyl methane (DDM) and isophorone diamine, were used. The prepared VDE resins with various curing parameters were characterized using FTIR, NMR, tensile test, bending test and water contact angle. Further, the interfacial adhesion feasibility of VDE resins on cellulose film was studied through the single-lap shear joint examination and compared with a commercial epoxy, DGEBA. The VDE-DDM resin exhibited excellent interfacial adhesion with cellulose than VDE-IPDA and DGEBA-DDM resins. The cured VDE-DDM thermoset showed a tensile strength of 86.0 ± 6.5 MPa, thermal stability of 241.0 °C at Td5%, and an elastic modulus of 2.9 ± 0.3 GPa, which is better than the commercial epoxy resin. Besides, the developed VDE-DDM resin was used to fabricate treated-jute fiber (TJF)-reinforced composites. The bio-based VDE-DDM/TJF composite's flexural strength was higher than the commercial epoxy resin composite, DGEBA-DDM/TJF. Furthermore, the phosphorus moiety of the VDE-DDM resin endows flame retardancy to the VDE-DDM/TJF composite during combustion. Overall, the appealing properties of bio-based VDE-DDM/TJF composite render environment-friendly and high-performance structural applications.


Assuntos
Celulose , Resinas Epóxi , Resinas Epóxi/química , Celulose/química , Compostos de Epóxi/química , Compostos Benzidrílicos
14.
Cureus ; 13(4): e14339, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33972897

RESUMO

Introduction Fracture of the clavicle bone is a very common injury owing to its subcutaneous location. Controversy exists about the optimal treatment of midshaft clavicle fractures in the presence of significant displacement and comminution of the fracture. Traditionally, non-surgical management was considered the first treatment option for most clavicle fractures. However, recent evidence shows that the non-surgical option causes more complications than previously reported. The purpose of this study was to compare the clinical and radiological outcomes of conservative treatment and surgical treatment for midshaft clavicle fractures. Materials and methods A total of 45 patients meeting the inclusion criteria were included in this randomized study. The patients were allocated to two groups: conservative and operative on an alternate basis. Patients in the conservative group were managed with figure-of-eight bandage, whereas patients in the operative group were treated surgically by plate fixation. Primary outcome was recorded at six weeks, three months, six months, and 12 months follow-up using the Disabilities of the Arm, Shoulder, and Hand (DASH) and American Shoulder and Elbow Surgeons (ASES) scores. We also assessed patient's satisfaction after the treatment, fracture union, and complication rates among the study cohort. Results The ASES scores were significantly better in the operative group at three months and six months follow-up; however, at 12 months follow-up, there was no significant difference in the score between the groups. Although not statistically significant, the DASH score was better in the operative group than in the conservative group at all the follow-ups. This study showed that the time to union was lesser, rate of non-union was lower, and return to work was faster on the operative group. The mean satisfaction score in the operative and conservative groups was 4.16±0.76 and 4.05±1.24, respectively (p = 0.76). Conclusion This study suggests that open reduction and internal fixation with plate reduced the incidence of mal-union and non-union; however, surgical treatment showed no significant difference in the functional outcome as compared to conservative treatment.

15.
Front Immunol ; 12: 631353, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017325

RESUMO

Acute graft-vs.-host (GVHD) disease remains a common complication of allogeneic stem cell transplantation with very poor outcomes once the disease becomes steroid refractory. Mesenchymal stem cells (MSCs) represent a promising therapeutic approach for the treatment of GVHD, but so far this strategy has had equivocal clinical efficacy. Therapies using MSCs require optimization taking advantage of the plasticity of these cells in response to different microenvironments. In this study, we aimed to optimize cord blood tissue derived MSCs (CBti MSCs) by priming them using a regimen of inflammatory cytokines. This approach led to their metabolic reprogramming with enhancement of their glycolytic capacity. Metabolically reprogrammed CBti MSCs displayed a boosted immunosuppressive potential, with superior immunomodulatory and homing properties, even after cryopreservation and thawing. Mechanistically, primed CBti MSCs significantly interfered with glycolytic switching and mTOR signaling in T cells, suppressing T cell proliferation and ensuing polarizing toward T regulatory cells. Based on these data, we generated a Good Manufacturing Process (GMP) Laboratory protocol for the production and cryopreservation of primed CBti MSCs for clinical use. Following thawing, these cryopreserved GMP-compliant primed CBti MSCs significantly improved outcomes in a xenogenic mouse model of GVHD. Our data support the concept that metabolic profiling of MSCs can be used as a surrogate for their suppressive potential in conjunction with conventional functional methods to support their therapeutic use in GVHD or other autoimmune disorders.


Assuntos
Técnicas de Reprogramação Celular/métodos , Reprogramação Celular/fisiologia , Sangue Fetal/citologia , Doença Enxerto-Hospedeiro/prevenção & controle , Células-Tronco Mesenquimais/metabolismo , Animais , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/imunologia , Citocinas/farmacologia , Feminino , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Camundongos , Camundongos Endogâmicos NOD , Controle de Qualidade
17.
Polymers (Basel) ; 13(7)2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33916412

RESUMO

By increasing the environmental concerns and depletion of petroleum resources, bio-based resins have gained interest. Recently, lignin, vanillin (4-hydroxy-3-methoxybenzaldehyde), and divanillin (6,6'-dihydroxy-5,5'-dimethoxybiphenyl-3,3'-dicarbaldehyde)-based resins have attracted attention due to the low cost, environmental benefits, good thermal stability, excellent mechanical properties, and suitability for high-performance natural fiber composite applications. This review highlights the recent use of lignin, vanillin, and divanillin-based resins with natural fiber composites and their synthesized processes. Finally, discussions are made on the curing kinetics, mechanical properties, flame retardancy, and bio-based resins' adhesion property.

18.
Carbohydr Res ; 499: 108222, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33401229

RESUMO

In this study, novel redox-sensitive nanoparticles based on xylan-lipoic acid (Xyl-LA) conjugate were developed for tumor targeted delivery of niclosamide (Nic) in cancer therapy. The niclosamide loaded xylan-lipoic acid conjugate nanoparticles (Xyl-LA/Nic NPs) showed redox responsive behaviour in presence of reductive glutathione (GSH), which indicate their suitability for intracellular drug release. The obtained Xyl-LA/Nic NPs exhibited uniform particle size (196 ± 1.64 nm), high loading capacity (~28.6 wt %) and excellent blood compatibility. The anticancer activity of the Niclosamide and the Xyl-LA/Nic NPs against the colon carcinoma cell lines (HCT-15, Colo-320) were evaluated by MTT assay and the overall results indicate that the Xyl-LA/Nic NPs significantly enhanced the therapeutic efficiency of niclosamide in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Niclosamida/farmacologia , Ácido Tióctico/química , Xilanos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Niclosamida/química , Oxirredução , Tamanho da Partícula
19.
Int J Radiat Oncol Biol Phys ; 109(1): 60-72, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841681

RESUMO

PURPOSE: Although vascular alterations in solid tumor malignancies are known to decrease therapeutic delivery, the effects of leukemia-induced bone marrow vasculature (BMV) alterations on therapeutic delivery are not well known. Additionally, functional quantitative measurements of the leukemic BMV during chemotherapy and radiation therapy are limited, largely due to a lack of high-resolution imaging techniques available preclinically. This study develops a murine model using compartmental modeling for quantitative multiphoton microscopy (QMPM) to characterize the malignant BMV before and during treatment. METHODS AND MATERIALS: Using QMPM, live time-lapsed images of dextran leakage from the local BMV to the surrounding bone marrow of mice bearing acute lymphoblastic leukemia (ALL) were taken and fit to a 2-compartment model to measure the transfer rate (Ktrans), fractional extracellular extravascular space (νec), and vascular permeability parameters, as well as functional single-vessel characteristics. In response to leukemia-induced BMV alterations, the effects of 2 to 4 Gy low-dose radiation therapy (LDRT) on the BMV, drug delivery, and mouse survival were assessed post-treatment to determine whether neoadjuvant LDRT before chemotherapy improves treatment outcome. RESULTS: Mice bearing ALL had significantly altered Ktrans, increased νec, and increased permeability compared with healthy mice. Angiogenesis, decreased single-vessel perfusion, and decreased vessel diameter were observed. BMV alterations resulted in disease-dependent reductions in cellular uptake of Hoechst dye. LDRT to mice bearing ALL dilated BMV, increased single-vessel perfusion, and increased daunorubicin uptake by ALL cells. Consequently, LDRT administered to mice before receiving nilotinib significantly increased survival compared with mice receiving LDRT after nilotinib, demonstrating the importance of LDRT conditioning before therapeutic administration. CONCLUSION: The developed QMPM enables single-platform assessments of the pharmacokinetics of fluorescent agents and characterization of the BMV. Initial results suggest BMV alterations after neoadjuvant LDRT may contribute to enhanced drug delivery and increased treatment efficacy for ALL. The developed QMPM enables observations of the BMV for use in ALL treatment optimization.


Assuntos
Medula Óssea/irrigação sanguínea , Terapia Neoadjuvante , Neovascularização Patológica , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Doses de Radiação , Animais , Linhagem Celular Tumoral , Camundongos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Dosagem Radioterapêutica , Microambiente Tumoral/efeitos da radiação
20.
Gels ; 6(4)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322561

RESUMO

Novel sodium carboxymethyl cellulose-g-poly (sodium acrylate)/Ferric chloride (CMC-g-PNaA/FeCl3) nanoporous hydrogel beads were prepared based on the ionic cross-linking between CMC-g-PNaA and FeCl3. The structure of CMC and CMC-g-PNaA were elucidated by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, and the elemental composition was analyzed by energy dispersive X-ray analysis (EDX). The physicochemical properties of the CMC-g-PNaA/FeCl3 hydrogel beads were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermogravimetric analysis (TGA). The swelling percentage of hydrogel beads was studied at different time periods. The obtained CMC-g-PNaA/FeCl3 hydrogel beads exhibited a higher nanoporous morphology than those of CMC-g-PNaA and CMC beads. Furthermore, an AFM image of the CMC-g-PNaA/FeCl3 beads shows granule type topology. Compared to the CMC-g-PNaA (189 °C), CMC-g-PNaA/FeCl3 hydrogel beads exhibited improvement in thermal stability (199 °C). Furthermore, CMC-g-PNaA/FeCl3 hydrogel beads depicted a higher swelling percentage capacity of around 1452%, as compared to CMC-g-PNaA (1096%). Moreover, this strategy with preliminary results could be useful for the development of polysaccharide-based hybrid hydrogel beads for various potential applications.

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