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1.
Polymers (Basel) ; 16(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38543433

RESUMO

Enhancing interfacial interactions in fiber-reinforced polymer composites (FRPCs) is crucial for improving their mechanical properties. This can be achieved through the incorporation of nanomaterials or chemically functional agents into FRPCs. This study reports the tailoring of the fiber-matrix interface in FRPCs using non-functionalized graphene nanoplatelets (GNPs) in combination with a waterborne, highly branched, multi-functional polyurethane dispersion (HBPUD). A unique ultrasonic spray deposition technique was utilized to deposit aqueous mixtures of GNP/HBPUDs onto the surfaces of carbon fiber fabrics, which were used to prepare epoxy-prepreg sheets and corresponding FRPC laminates. The influence of the polyurethane (PU) and GNP content and their ratio at the fiber-matrix interface on the tensile properties of resulting high-performance composites was systematically investigated using stress-strain analysis of the produced FRPC plates and SEM analysis of their fractured surfaces. A synergistic stiffening and toughening effect was observed when as low as 20 to 30 mg of GNPs was deposited per square meter of each side of the carbon fiber fabrics in the presence of the multi-functional PU layer. This resulted in a significant improvement in the tensile strength from 908 to 1022 MPa, while maintaining or slightly improving the initial Young's modulus from approximately 63 to 66 MPa.

2.
ACS Omega ; 8(49): 47173-47186, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107921

RESUMO

One-component epoxy resins (OCERs) are proposed to overcome the energy inefficiency and processing difficulties of conventional two-component epoxy resins by employing latent curing agents, specifically thermal latent curing agents (TLCs). Despite recent progress, the need for TLCs with a simple preparation method for different curing agents, epoxy resins, and process conditions remains. Here, tailorable TLCs were prepared by forming complexes between imidazole (Im) and amphiphilic polyoxazoline copolymers with tunable structures and properties by a solvent evaporation method. The obtained TLCs were manually mixed with DGEBA to prepare OCERs. The miscibility of the complexes with DGEBA was studied, considering the functionalities of copolymers. The curing behaviors of TLCs were compared using dynamic Differential Scanning Calorimetry (DSC) studies considering the side chain and composition of the copolymers, copolymer:Im ratio, and concentration of Im in DGEBA. The curing behavior of the promising OCERs was studied by isothermal DSC studies to investigate their stability at different temperatures and curing rate at elevated temperatures revealing the stability of these OCERs.

4.
Indian J Hematol Blood Transfus ; 39(2): 220-227, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37006982

RESUMO

Purpose: The receptor for advanced glycation end products (RAGE) upregulated during the onset and progression of cancer and bone-related pathologies. In this study, we aimed to investigate the role of serum advanced glycation end products (AGEs), soluble RAGE (sRAGE) and high mobility group box 1 (HMGB1), in multiple myeloma (MM). Methods: AGEs, sRAGE and HMGB1 concentrations of 54 newly diagnosed MM patients and 30 healthy volunteers were measured by ELISA. The estimations were done only once at diagnosis. The medical records of the patients were evaluated. Results: There was no significant difference between the AGEs and sRAGE levels between the patient and control groups (p = 0.273, p = 0.313). In ROC analysis, a HMGB1 cutoff value of > 9170 pg/ml accurately discriminated MM patients (AUC = 0.672, 95% CI 0.561-0.77, p = 0.0034). AGEs level was found to be significantly higher in early-stage disease and HMGB1 in advanced disease (p = 0.022, p = 0.026). High HMGB1 levels were detected in patients whose with better first-line treatment response (p = 0.019). At 36 months, 54% of patients with low AGE were alive, compared to 79% of patients with high AGE (p = 0.055). Patients with high HMGB1 levels tended to have a longer PFS (median 43 mo [95% CI; 20.68-65.31] ) compared to patients with low HMGB1 levels (median 25 mo [95% CI; 12.39-37.6], p = 0.054). Conclusion: In this study, a significant elevation of serum HMGB1 level was found in MM patients. In addition, the positive effects of RAGE ligands on treatment response and prognosis were determined.

5.
Healthcare (Basel) ; 11(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37107948

RESUMO

The COVID-19 pandemic has hugely affected the textile and apparel industry. Besides the negative impact due to supply chain disruptions, drop in demand, liquidity problems, and overstocking, this pandemic was found to be a window of opportunity since it accelerated the ongoing digitalization trends and the use of functional materials in the textile industry. This review paper covers the development of smart and advanced textiles that emerged as a response to the outbreak of SARS-CoV-2. We extensively cover the advancements in developing smart textiles that enable monitoring and sensing through electrospun nanofibers and nanogenerators. Additionally, we focus on improving medical textiles mainly through enhanced antiviral capabilities, which play a crucial role in pandemic prevention, protection, and control. We summarize the challenges that arise from personal protective equipment (PPE) disposal and finally give an overview of new smart textile-based products that emerged in the markets related to the control and spread reduction of SARS-CoV-2.

6.
Water Sci Technol ; 87(6): 1529-1541, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37001163

RESUMO

Wastewater from the textile industry contains high concentrations of pollutants, so the wastewater must be treated before it is discharged. In addition, the reuse of treated wastewater should be considered from an environmental point of view, as large volumes of wastewater are produced. Since textile wastewater mainly contains dyestuffs, it must be treated effectively using environmentally friendly technologies. Membrane processes are widely used in textile wastewater treatment as they have distinct advantages over conventional wastewater treatment methods. This study reports the pilot-scale manufacturing and characterization of three different NF membranes. Three different types of membranes were fabricated. The fabricated membranes were compared through characterization by surface properties, chemical structure and morphology. Membranes were tested for pure water flux. Then the synthetic wastewater (SWW) was tested for flux and rejection. Lastly, the textile wastewater was tested. The textile wastewater flux of pure piperazine (PIP), 60% S-DADPS and 0.04% halloysite nanotubes (HNTs) were 22.42, 79.58 and 40.06 L m-2 h-1. It has been proven that the 60% s-DADPS membrane provides up to four times improvement in wastewater flux and simultaneously. In addition, NF membranes produced using HNT and sDADPS on a pilot scale have brought innovation to the literature with the good results obtained.


Assuntos
Nanotubos , Purificação da Água , Águas Residuárias , Argila , Membranas Artificiais , Filtração , Purificação da Água/métodos , Indústria Têxtil , Têxteis
7.
ACS Omega ; 7(44): 40067-40077, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36385860

RESUMO

Poly(2-oxazoline)s (POZs) are widely investigated for their applications in various fields due to their unique properties. To exploit and combine different characteristics of the POZ family, 2-oxazoline monomers can be copolymerized to prepare tailor-made copolymers with the desired glass transition temperature (T g), melting temperature (T m), amphiphilicity, and functionality. Here, we report the synthesis and characterization of 2-oxazoline monomers and a range of POZ copolymers produced, thereof. 2-Propyl-2-oxazoline (PrOZ) and 2-pentyl-2-oxazoline (PeOZ) monomers were synthesized by two different methods starting from nitriles or carboxylic acids. A number of POZ copolymers were synthesized by copolymerization of 2-ethyl-2-oxazoline (EOZ) with either one of PrOZ, PeOZ, or 2-phenyl-2-oxazoline (PhOZ) at three different compositions (25:75, 50:50, and 75:25) and three molecular weights (1000, 2000, and 5000 Da). The successful synthesis of the monomers and copolymers was demonstrated through their structural analysis by 1H NMR and FTIR. SEC results confirmed the targeted molar masses of the copolymers and living nature of the polymerization by showing low dispersity values. Thermal properties of the copolymers were studied using DSC and TGA. DSC studies revealed the amorph and random state of the copolymers with obtained T g values for the copolymers in the range of -3 to 84 °C depending on their molecular weight and type of the side chain. While the presence of longer aliphatic side chains resulted in lower T g values, the presence of 2-phenyl substituents on the polymer led to higher T g values. The decomposition temperatures determined by TGA were in the range of 328 to 383 °C depending on the molecular weight, composition, and side chain of the copolymers. It was observed that higher molecular weights led to higher T g values and decomposition temperatures. While copolymers with aliphatic side chains exhibited a single-step decomposition profile, the decomposition of copolymers having aromatic side chains occurred in multiple steps. The variations in the molecular weight, composition, and side chains of the copolymers resulted in a library of tailorable amphiphilic copolymers suitable for multiple applications ranging from biomedical applications to composite manufacturing.

8.
Scand J Clin Lab Invest ; 82(1): 28-36, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34915774

RESUMO

INTRODUCTION: Inherited factor VII (FVII) deficiency (FVIID) is the most common of inherited rare bleeding disorders. Other determinants of clinical severity apart from FVII level (FVIIL) include genetic and environmental factors. We aimed to identify the cut-off FVIILs for general and severe bleedings in patients with FVIID by using an online national registry system including clinical, laboratory, and demographic characteristics of patients. METHODS: Demographic, clinical, and laboratory data of patients with FVIID extracted from the national database, constituted by the Turkish Society of Hematology, were examined. Bleeding phenotypes, general characteristics, and laboratory features were assessed in terms of FVIILs. Bleeding rates and prophylaxis during special procedures/interventions were also recorded. RESULTS: Data from 197 patients showed that 46.2% of patients had FVIIL< 10%. Most bleeds were of mucosal origin (67.7%), and severe bleeds tended to occur in younger patients (median age: 15 (IQR:6-29)). Cut-off FVIILs for all and severe bleeds were 16.5% and 7.5%, respectively. The major reason for long-term prophylaxis was observed as central nervous system bleeding (80%). CONCLUSION: Our data are consistent with most of the published literature in terms of cut-off FVIIL for bleeding, as well as reasons for prophylaxis, showing both an increased severity of bleeding and younger age at diagnosis with decreasing FVIIL. However, in order to offer a classification similar to that in Hemophilia A or B, data of a larger cohort with information about environmental and genetic factors are required.


Assuntos
Transtornos Herdados da Coagulação Sanguínea , Deficiência do Fator VII , Fator VII/uso terapêutico , Deficiência do Fator VII/diagnóstico , Deficiência do Fator VII/tratamento farmacológico , Deficiência do Fator VII/genética , Hemorragia/prevenção & controle , Humanos , Sistema de Registros , Turquia/epidemiologia
9.
Clin Lymphoma Myeloma Leuk ; 21(11): e922-e927, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34353778

RESUMO

BACKGROUND: Diffuse large B cell lymphoma is the most frequent aggressive non-Hodgkin lymphoma. Predicting response and estimating prognosis earlier makes management of this heterogeneous lymphoma more satisfying. Interim PET response is established in Hodgkin Lymphoma to tailor the therapy but results for non-Hodgkin Lymphoma is unconvincing. In the current study evaluation of interim PET and survival outcomes of 103 DLBCL patients is performed. PATIENTS AND METHODS: About 103 Patients with DLBCL followed up in a single center between 2009 and 2019 were enrolled the study. All patients received R-CHOP chemoimmunotherapy at first line. Interim PET was performed after at least one or more cycles. All PET scans were performed with 18F-FDG isotope as PET/CT. PET scoring results were evaluated according to the 5-Point Deauville Scoring system defined in the National Comprehensive Cancer Network clinical guidelines for iPET and eotPET. 5-P DS of scores of 1 to 3 were defined as negative scans, and scores of 4 to 5 were considered to be positive scans. RESULTS: Forty-six (44.7%) Female and 57 (55.3%) male aged between 25 and 83 (median 57) years newly diagnosed DLBCL patients were enrolled in the study. Median PFS was 21 (interquartile range 8.5-53.7) months and median OS was 33.5 (interquartile range 12.5-62.9) months for the total cohort. Positive predictive value of interim PET according to Deauville scoring system was 65.4% and negative predictive value was 77.9%. CONCLUSION: Our study showed that according to Deauville 5 point scale (D 5PS) scoring system, interim PET-positive patients have shorter both PFS and OS than iPET-negative patients.


Assuntos
Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
10.
Turk J Haematol ; 38(3): 211-217, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-33947178

RESUMO

Objective: Constantly increasing health expenditures lead to the use of generic molecules and generic versions of bortezomib have been used for a long time. The aim of this study is to retrospectively examine the effectiveness, side effects, and reliability of generic bortezomib in newly diagnosed multiple myeloma (MM) patients. Materials and Methods: The data of 95 patients who received four cycles of bortezomib as first- or second-line therapy in a single center were retrospectively recorded. Treatment responses, side effects, and progression-free survival (PFS) rates were calculated and compared. Results: Of the 95 patients, 42 used the original and 53 used the generic molecule. Epidemiological data, MM types, genetic risk groups, laboratory values at diagnosis, and bortezomib treatment lines (as a first line or second) were evaluated and there was no statistical difference between the two groups. When the response rates were evaluated according to International Myeloma Working Group criteria, there was no significant difference (p=0.42). Rates of partial response and higher responses were similar (81% vs. 79.2%, p=0.84). PFS rates were 42.8 months with the original and 37.8 months with the generic molecule (p=0.68). Side effects were seen in 44.2% of all patients, and the most common side effects were neuropathy, cytopenia, and infection. These rates were similar in the two groups (p=0.55). Conclusion: Although this retrospective study is limited in scope, it is the first study comparing the original molecule of bortezomib with a generic version. There were no statistical differences between the two groups in terms of treatment responses, PFS, or side effects. However, large-scale evaluations will help obtain more data on this subject.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Bortezomib/uso terapêutico , Dexametasona/uso terapêutico , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
11.
Int J Lab Hematol ; 43(4): 638-644, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33904653

RESUMO

INTRODUCTION: Hodgkin lymphoma (HL) is unusual among malignancies, with inflammation playing such a prominent role in its pathogenesis. S100A8/A9 (calprotectin) is a heterodimeric protein, which has a role in the inflammatory response and oncogenesis. In this study in HL patients, the correlation between serum S100A8/A9 levels and treatment responses was investigated along with whether this marker is correlated with other inflammatory markers. MATERIALS AND METHODS: Thirty-three HL patients and 20 healthy volunteers were included. Demographic and clinical characteristics were recorded. Calprotectin levels were measured with Human S100A8/A9 Heterodimer Quantikine ELISA kit. Calprotectin levels were measured twice in patients, before and after treatment, and once in the control group. Treatment responses were evaluated with positron emission tomography-computed tomography (PET-CT). RESULTS: The mean age of patients was 44.3 ± 18.1 (66.3% male). The median (IQR) values of S100A8/A9 before and after treatment in the patient group were 4.98 (2.6-7.8) and 1.87 (1.1-4.8)µg/mL. Median (IQR) S100A8/A9 concentration in the control group was 1.41 (0.98-2.73)µg/mL. In patients, pretreatment values were significantly higher than in controls (P < .001). However, median values of patients after treatment and controls were similar. Patient median S100A8/A9 levels were significantly lower post-treatment compared with pretreatment values (P = .001). When inflammatory markers were examined within groups, no relationship was found between markers. In ROC analysis, a S100A8/A9 cutoff value of ≥3.31µg/mL accurately discriminated end-of-treatment PET positivity (AUC = 0.78; 95% CI 0.58-0.98; accuracy = 76.2%). CONCLUSION: S100A8/A9 may be a potential biomarker for treatment response in HL independent of inflammation. This is the first study to investigate and show this finding. However, further large-scale studies are still required.


Assuntos
Biomarcadores Tumorais/sangue , Calgranulina A/sangue , Calgranulina B/sangue , Doença de Hodgkin/sangue , Doença de Hodgkin/terapia , Proteínas de Neoplasias/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Nanomaterials (Basel) ; 11(3)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802645

RESUMO

The morphology of nanostructures is a vital parameter to consider in components comprised of materials exhibiting specific functionalities. The number of process steps and the need for high temperatures can often be a limiting factor when targeting a specific morphology. Here, we demonstrate a repeatable synthesis of different morphologies of a highly crystalline monoclinic phase of vanadium dioxide (VO2(M)) using a one-step hydrothermal method. By adjusting the synthesis parameters, such as pH, temperature, and reducing agent concentration in the precursor, VO2 nanostructures with high uniformity and crystallinity are achieved. Some of these morphologies were obtained via the choice of the reducing agent that allowed us to skip the annealing step. Our results indicate that the morphologies of the nanostructures are very sensitive to the hydrazine hydrate (N2H4.H2O) concentration. Another reducing agent, dodecylamine, was used to achieve well-organized and high-quality VO2(M) nanotubes. Differential scanning calorimetry (DSC) experiments revealed that all samples display the monoclinic-to-tetragonal structural transition (MTST) regardless of the morphology, albeit at different temperatures that can be interpreted as the variations in overheating and undercooling limits. VO2(M) structures with a higher surface to volume ratio exhibit a higher overheating limit than those with low ratios.

13.
Water Sci Technol ; 83(2): 271-283, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33504693

RESUMO

In this paper, ultrafiltration (UF) flat sheet membranes were manufactured by introducing two diverse halloysite nanotubes (HNT) size (5 µm and 63 µm) and five different (0, 0.63, 1.88, 3.13, 6.30 wt %) ratios by wet phase inversion. Some characterization methods which are contact angle, zeta potential, viscosity, scanning electron microscopy (SEM) and Young's modulus measurements were used for ultrafiltration membranes. Synthetic dye waters which were Setazol Red and Reactive Orange were used for filtration performance tests. These dye solutions were filtered in three different pH conditions and three different temperature conditions for pH and temperature resistance to understand how flux and removal efficiency change. The best water permeability results were obtained as 190.5 LMH and 192 LMH, for halloysite nanotubes (HNT) sizes of 5 µm and 63 µm respectively. The best water and dye performance of UF membrane contains 1.88% w/w ratio of HNT, which showed increased water flux and dye flux of membranes according to different HNT concentrations including ultrafiltration membranes.


Assuntos
Nanocompostos , Nanotubos , Argila , Filtração , Membranas Artificiais , Ultrafiltração
14.
ACS Omega ; 5(29): 17962-17972, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32743169

RESUMO

Halloysite nanotubes (HNTs) have attracted great attention in the field of nanotechnology as natural, high value-added nanomaterials. Despite their significant potential as carriers of active agents and fillers in nanocomposite structures, inhomogeneity of HNTs in terms of length and diameter along with their agglomeration tendency poses important obstacles for the utilization of them in a wider range of applications. Here, a facile, three-step separation protocol that allows the sorting of HNTs into agglomeration-free, uniform size fractions is reported. The protocol consists of coating of HNTs with polydopamine to impart hydrophilicity and aqueous dispersibility, followed by their ultrasonication and centrifugation at varying velocities for size-based separation. Particle size distribution analysis by scanning electron microscopy and dynamic light scattering has demonstrated that the separation protocol resulted in uniform HNT fractions of varying agglomeration states and particle sizes. The highest quality fraction obtained with 18% yield was free of agglomerations and consisted of HNTs of uniform lengths and diameters. The polydopamine coating on HNTs which facilitated the separation was demonstrated to be removed by a simple heat treatment that preserved the crystal structure of HNTs. The impact of the separation protocol on the loading and functionalization capacity of halloysites was investigated. Highest quality HNTs presented 4.1-fold increase in lumen loading and 1.9-fold increase in covalent surface coupling ratios compared to the loading and functionalization ratios obtained with raw HNTs. Similarly, sorted, high-quality HNTs were demonstrated to be better dispersed in a polymeric matrix, resulting in polymeric nanocomposites with significantly enhanced mechanical properties compared to nanocomposites prepared with raw HNTs. The three-step separation protocol presented here provides a toolbox that allows sorting of raw HNTs into uniform fractions of different size ranges, from which HNTs of desired qualities required by different applications can be selected.

17.
Sci Rep ; 6: 33178, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27630079

RESUMO

Multimaterial additive manufacturing or three-dimensional (3D) printing of hydrogel structures provides the opportunity to engineer geometrically dependent functionalities. However, current fabrication methods are mostly limited to one type of material or only provide one type of functionality. In this paper, we report a novel method of multimaterial deposition of hydrogel structures based on an aspiration-on-demand protocol, in which the constitutive multimaterial segments of extruded filaments were first assembled in liquid state by sequential aspiration of inks into a glass capillary, followed by in situ gel formation. We printed different patterned objects with varying chemical, electrical, mechanical, and biological properties by tuning process and material related parameters, to demonstrate the abilities of this method in producing heterogeneous and multi-functional hydrogel structures. Our results show the potential of proposed method in producing heterogeneous objects with spatially controlled functionalities while preserving structural integrity at the switching interface between different segments. We anticipate that this method would introduce new opportunities in multimaterial additive manufacturing of hydrogels for diverse applications such as biosensors, flexible electronics, tissue engineering and organ printing.

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