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1.
Anal Chim Acta ; 1316: 342861, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969410

RESUMO

BACKGROUND: The high toxicity of hexavalent chromium [Cr (VI)] could not only cause harmful effects on humans, including carcinogenicity, respiratory issues, genetic damage, and skin irritation, but also contaminate drinking water sources, aquatic ecosystems, and soil, impairing the reproductive capacity, growth, and survival of organisms. Due to these harmful effects, detecting toxic Cr (VI) is of great significance. However, the rapid, simple, and efficient detection at a low Cr (VI) concentration is extremely challenging, especially in an acidic condition (existing as HCrO4-) due to its low adsorption free energy. RESULTS: A diketopyrrolopyrrole-based small molecule (DPPT-PhSMe) is designed and characterized to act as a chemosensor, which allows a high selectivity to Cr (VI) at an acidic condition with a low limit of detection to 10-8 M that is two orders of magnitude lower than the cut of limit (1 µM) recommended by World Health Organization (WHO). Mechanism study indicates that the rich sulfur atoms enhance the affinity to HCrO4-. Combining with favorable features of diketopyrrolopyrrole, DPPT-PhSMe not only allows dual-mode detection (colorimetric and spectroscopic) to Cr (VI), but also enables disposable paper-based sensor for naked-eye detection to Cr (VI) from fully aqueous media. The investigation of DPPT-PhSMe chemosensor for the quantification of Cr (VI) in real life samples demonstrates a high reliability and accuracy with an average percentage recovery of 102.1 % ± 4 (n = 3). SIGNIFICANCE: DPPT-PhSMe represents the first diketopyrrolopyrrole-derived chemosensor for efficient detection to toxic Cr (VI), not only providing a targeted solution to the bottleneck of Cr (VI) detection in acidic conditions (existing as HCrO4-) caused by its low adsorption free energy, but also opening a new scenario for simple, selective, and efficient Cr (VI) detection with conjugated dye molecules.


Assuntos
Cromo , Limite de Detecção , Pirróis , Poluentes Químicos da Água , Cromo/análise , Pirróis/química , Poluentes Químicos da Água/análise , Cetonas/química , Cetonas/análise , Água/química
2.
BMC Oral Health ; 24(1): 760, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965507

RESUMO

BACKGROUND: Preservation of the remaining structures while maintaining an esthetic appearance is a major objective in removable partial prosthodontics. So, the aim of the current study was to compare the stresses induced on the supporting structures by two digitally produced esthetic core materials; Zirconia and Polyetheretherketone when used as an extracoronal attachment in distal extension removable partial dentures using strain gauge analysis. METHODS: A mandibular Kennedy class II stone cast with the necessary abutments' preparations was scanned. The mandibular left canine and first premolar teeth were virtually removed. An acrylic mandibular left canine and first premolar teeth were prepared with heavy chamfer finish line and scanned. Virtual superimposition of the acrylic teeth in their corresponding positions was done. Two strain gauge slots were designed: distal to the terminal abutment and in the residual ridge. Two models and two sets of scanned teeth were digitally printed. The printed teeth were then placed in their corresponding sockets in each model and scanned. The attachment design was selected from the software library and milled out of Zirconia in the model ZR and Polyetheretherketone in the model PE. Five removable partial dentures were constructed for each model. The strain gauges were installed in their grooves. A Universal testing machine was used for unilateral load application of 100 N (N). For each removable partial denture, five measurements were made. The data followed normal distribution and were statistically analyzed by using unpaired t test. P value < 0.05 was considered to be statistically significant. RESULTS: During unilateral loading unpaired t test showed statistically significant difference (p = 0.0001) in the microstrain values recorded distal to the abutment between the models ZR (-1001.6 µÎµ ± 24.56) and PE (-682.6 µÎµ ± 22.18). However, non statistically significant difference (p = 0.3122) was observed in the residual ridge between them; ZR (16.2 µÎµ ± 4.53) and PE (15 µÎµ ± 3.74). CONCLUSIONS: In removable partial dentures, Polyetheretherketone extracoronal attachment induces less stress on the supporting abutments compared to the zirconia one with no difference in the stresses induced by them on the residual ridge.


Assuntos
Benzofenonas , Planejamento de Dentadura , Prótese Parcial Removível , Cetonas , Polímeros , Zircônio , Cetonas/química , Humanos , Zircônio/química , Polietilenoglicóis , Análise do Estresse Dentário , Materiais Dentários/química , Desenho Assistido por Computador , Dente Suporte , Estresse Mecânico , Estética Dentária , Teste de Materiais
3.
Bull Exp Biol Med ; 177(1): 155-161, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38963597

RESUMO

Experimental model of resection craniotomy with subsequent reconstruction of the defect with a polymer implant enables comprehensive assessment of functional and ultrastructural changes during replacement of the damaged tissue. Reconstruction of a skull defect was accompanied by transient motor disturbance in the acute period and did not cause functional disorders and neurological deficits in a delayed period. Histological examination of osteal and brain tissue revealed no pathological reactions that could be associated with the response to the chemical components of the implant.


Assuntos
Benzofenonas , Craniotomia , Polietilenoglicóis , Polímeros , Crânio , Polímeros/química , Animais , Crânio/cirurgia , Crânio/lesões , Crânio/diagnóstico por imagem , Polietilenoglicóis/química , Craniotomia/métodos , Ratos , Masculino , Procedimentos de Cirurgia Plástica/métodos , Cetonas/química , Materiais Biocompatíveis/química , Encéfalo/cirurgia , Ratos Wistar
4.
BMC Oral Health ; 24(1): 765, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970080

RESUMO

OBJECTIVE: To determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials. MATERIALS AND METHODS: One hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass-ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer's instructions. Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α < 0.05. The surface topography was evaluated by scanning electron microscopy (SEM) and analyzed using energy-dispersive X-ray (EDX) spectroscopy to determine changes in the surface chemical composition. RESULTS: Both types of smoking caused significant increases in the surface roughness of all the samples. There was a significant difference in color change between CS and HTP for all materials with different surface finish (P < 0.01) and zirconia had the greatest effect on color change (P < 0.001). In contrast, polyetheretherketone (PEEK) "BioHPP" had the least effect (P < 0.001). CONCLUSION: Exposure to different types of smoking induce changes in the surface topography and color of different esthetic restorative materials. Compared with HTP, conventional cigarette smoke has a greater effect on the surface roughness and color stability of esthetic restorative materials. The glazed surfaces showed less change in surface topography than did the polished surfaces. Zirconia showed better color stability when compared to polyetheretherketone (PEEK).


Assuntos
Cerâmica , Fumar Cigarros , Desenho Assistido por Computador , Materiais Dentários , Porcelana Dentária , Cetonas , Polietilenoglicóis , Polímeros , Propriedades de Superfície , Produtos do Tabaco , Zircônio , Polietilenoglicóis/química , Zircônio/química , Produtos do Tabaco/efeitos adversos , Cerâmica/química , Cetonas/química , Porcelana Dentária/química , Fumar Cigarros/efeitos adversos , Materiais Dentários/química , Benzofenonas , Teste de Materiais , Temperatura Alta , Humanos , Cor , Restauração Dentária Permanente
5.
J Org Chem ; 89(14): 10363-10370, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38955772

RESUMO

The stereoselective synthesis of meso-diaminopimelic acid (meso-DAP), the key cross-linking amino acid of the peptidoglycan cell wall layer in Gram-negative bacteria, and its biological precursor, l,l-DAP, is described. The key step involved stereoselective reduction of a common enone-derived amino acid by substrate- or reagent-based control. Overman rearrangement of the resulting allylic alcohols, concurrent alkene hydrogenation and trichloroacetamide reduction, and subsequent ruthenium-catalyzed arene oxidation completed the synthesis of each stereoisomer. The synthetic utility of this approach was demonstrated with the efficient preparation of an l,l-DAP-derived dipeptide.


Assuntos
Ácido Diaminopimélico , Estereoisomerismo , Ácido Diaminopimélico/química , Ácido Diaminopimélico/síntese química , Aminoácidos/química , Aminoácidos/síntese química , Estrutura Molecular , Catálise , Oxirredução , Cetonas/química
6.
Chin J Dent Res ; 27(2): 161-168, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38953481

RESUMO

OBJECTIVE: To evaluate the effect of different adhesives and veneering resins on the shear bond strength (SBS) of polyetheretherketone (PEEK). METHODS: A total of 138 PEEK specimens were randomly divided into 6 groups according to adhesive material application: Control (C, no application), Adhese Universal (A) (Ivoclar Vivadent, Schaan, Liechtenstein), Gluma Bond Universal (G) (Heraeus Kulzer, South Bend, IN, USA), G-PremioBOND (P) (GC Corporation, Tokyo, Japan), Single Bond Universal (S) (3M, Saint Paul, MN, USA) and visio.link (V) (Bredent, Senden, Germany). Each adhesive group was divided into two subgroups according to the type of veneering material: Estenia direct composite (D) and Gradia Plus indirect composite (IN) (both GC Corporation). After the veneering process, the specimens were aged by thermal cycling. Kruskal-Wallis and Mann-Whitney U tests were used for SBS analysis (P < 0.05). RESULTS: The highest SBS results were obtained in the VIN group, followed by the VD, PD, GIN, AIN, AD, SIN, SD, PIN, GD, CIN and CD groups, respectively (P = 0.001). There were no significant differences in terms of the type of veneering composite when the same adhesive was applied (P > 0.05), except for Gluma Bond Universal (P = 0.009). All the adhesives tested showed clinically acceptable SBS results. CONCLUSION: Visio.link offered the highest adhesion to PEEK, whereas the tested universal adhesives may be used as an alternative to visio.link in clinical settings. It was determined that changing the veneer type has no statistical difference when the same adhesive material is used.


Assuntos
Benzofenonas , Resinas Compostas , Facetas Dentárias , Cetonas , Polietilenoglicóis , Polímeros , Resistência ao Cisalhamento , Cetonas/química , Teste de Materiais , Colagem Dentária , Humanos , Cimentos de Resina , Análise do Estresse Dentário , Bis-Fenol A-Glicidil Metacrilato
7.
J Indian Prosthodont Soc ; 24(3): 252-258, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946508

RESUMO

AIM: This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to assess the shear bond strength (SBS) and color stability of zirconia and PEEK before and after aging, addressing critical concerns in dental restorative applications. SETTINGS AND DESIGN: The current in vitro study used 96 samples, 48 of which were divided into two groups, zirconia and PEEK, before and after thermocycling. A dual-axis chewing simulator was used for thermocycling. SBS was measured using a universal testing machine, and color stability was checked using a reflective spectrophotometer. MATERIALS AND METHODS: Ninety-six samples were categorized into zirconia and PEEK groups, each with subgroups undergoing thermocycling. Samples were prepared using computer-aided design/computer-aided manufacturing milling and veneered with composite resin. Thermocycling involved 10,000 cycles, simulating stress levels equivalent to approximately 1 year of clinical use. SBS was assessed using standardized tests. Stereomicroscopic analysis was performed to evaluate the type of failure. Color stability of the core materials with indirect composite was done using a spectrophotometer before and after aging. STATISTICAL ANALYSIS USED: Statistical analysis included paired t-tests and independent t-tests in SPSS software. RESULTS: The results revealed that SBS values for composite on PEEK decreased from 13.86 ± 0.164 MPa before thermocycling to 13.46 ± 0.185 MPa after thermocycling, with a significant difference (P < 0.005). However, both pre- and postthermocycling values for PEEK were higher than zirconia. The t-test confirmed the lower bond strength of composite to zirconia, with a noteworthy improvement after aging. Stereomicroscopic images revealed adhesive failure for the zirconia group and mixed (adhesive and cohesive) failure for the PEEK group. ΔE values were 3.21 ± 0.127 and 2.93 ± 0.142 for zirconia and PEEK groups, respectively (P < 0.005). CONCLUSION: Within the limitations of this study, it can be deduced that PEEK is a feasible substitute for zirconia when used in conjunction with indirect composite for the fabrication of dental prostheses.


Assuntos
Benzofenonas , Cor , Resinas Compostas , Colagem Dentária , Cetonas , Polietilenoglicóis , Polímeros , Zircônio , Zircônio/química , Cetonas/química , Polietilenoglicóis/química , Polímeros/química , Resinas Compostas/química , Técnicas In Vitro , Colagem Dentária/métodos , Teste de Materiais , Resistência ao Cisalhamento , Materiais Dentários/química , Análise do Estresse Dentário , Humanos
8.
J Indian Prosthodont Soc ; 24(3): 245-251, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946507

RESUMO

AIM: Synthetic inorganic materials are commonly used as reinforcing agents in polyetheretherketone (PEEK) composite, whereas natural organic plant-based reinforcing agents are negligible. Surface hardness, roughness, and wettability are indicative factors of osseointegration behavior to be used as an implant material. This study evaluated micro surface hardness (MSH), nano surface hardness (NSH), surface roughness (SR), and contact angle (CA) of PEEK-Azadirachta indica reinforced at 10 wt%, 20 wt%, and 30 wt%. SETTINGS AND DESIGN: This was an in vitro study. MATERIALS AND METHODS: Neem (A. indica) leaf nanoparticles were prepared and reinforced with PEEK powder at 10%, 20%, and 30% weight ratios by injection molding. Sixty specimens underwent the microhardness and CA testing using a digital microhardness tester, and CA goniometer, respectively, and later nanoindentation test to analyze the nanohardness and SR. STATISTICAL ANALYSIS USED: A one-way ANOVA test with a 95% confidence interval for MSH and NSH, SR, and CA was performed on the samples. A post hoc Bonferroni test was conducted (α = 0.05) to compare the groups. RESULTS: There was a significant increase in nanohardness (P = 0.000) with zero difference in microhardness (P = 0.514). The addition of 10 wt%, 20 wt%, and 30 wt% nanoparticles increased the SR value of the pure PEEK from 273.19 nm to 284.10 (3.99%), 296.91 (8.68%), and 287.54 (5.24%), respectively. In the analysis of the CA, CA 20% shows the lowest angle (63.69) with the highest for control specimens (82.39). There is an increase in the PEEK composite SR with a decrease in CA. CONCLUSIONS: The addition of plant-derived nanoparticles into the PEEK matrix has a significant impact on the hardness and hydrophobicity enhancing cell growth and osteoblastic differentiation during osseointegration of dental implants.


Assuntos
Benzofenonas , Cetonas , Nanopartículas , Polietilenoglicóis , Polímeros , Propriedades de Superfície , Molhabilidade , Polietilenoglicóis/química , Cetonas/química , Nanopartículas/química , Dureza , Técnicas In Vitro , Implantes Dentários , Teste de Materiais/métodos , Folhas de Planta/química
9.
Chem Biol Drug Des ; 104(1): e14581, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38997237

RESUMO

N-heterocyclic compounds are important molecular scaffolds in the search for new drugs, since most drugs contain heterocyclic moieties in their molecular structure, and some of these classes of heterocycles are able to provide ligands for two or more biological targets. Ketene dithioacetals are important building blocks in organic synthesis and are widely used in the synthesis of N-heterocyclic compounds. In this work, we used double vinylic substitution reactions on ketene dithioacetals to synthesize a small library of heterocyclic derivatives and evaluated their cytotoxic activity in breast and ovarian cancer cells, identifying two benzoxazoles with good potency and selectivity. In silico predictions indicate that the two most active derivatives exhibit physicochemical properties within the range of drug-like compounds and showed potential to interact with HDAC8 and ERK1 cancer-related targets.


Assuntos
Antineoplásicos , Etilenos , Compostos Heterocíclicos , Cetonas , Humanos , Linhagem Celular Tumoral , Etilenos/química , Etilenos/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Cetonas/química , Cetonas/farmacologia , Cetonas/síntese química , Relação Estrutura-Atividade , Histona Desacetilases/metabolismo , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Acetais/química , Acetais/farmacologia , Acetais/síntese química , Proteínas Repressoras
10.
J Agric Food Chem ; 72(28): 15778-15787, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38951118

RESUMO

Enzymatic oxygenation of various cyclic ketones into lactones via Baeyer-Villiger monooxygenases (BVMOs) could provide a promising route for synthesizing fragrances and pharmaceutical ingredients. However, unsatisfactory catalytic activity and thermostability restricted their applications in the pharmaceutical and food industries. In this study, we successfully improved the catalytic activity and thermostability of a Baeyer-Villiger monooxygenase (OgBVMO) from Oceanicola granulosus by reshaping the binding pocket. As a result, mutant OgBVMO-Re displayed a 1.0- to 6.4-fold increase in the activity toward branched cyclic ketones tested, accompanied by a 3 °C higher melting point, and a 2-fold longer half-life time (t1/2 (45 °C)). Molecular dynamics simulations revealed that reshaping the binding pocket achieved strengthened motion correlation between amino acid residues, appropriate size of the substrate-binding pocket, beneficial surface characteristics, lower energy barriers, and shorter nucleophilic distance. This study well demonstrated the trade-off between the enzyme activity and thermostability by reshaping the substrate-binding pocket, paving the way for further engineering other enzymes.


Assuntos
Estabilidade Enzimática , Oxigenases de Função Mista , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Sítios de Ligação , Cinética , Biocatálise , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Especificidade por Substrato , Simulação de Dinâmica Molecular , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Temperatura Alta , Cetonas/química , Cetonas/metabolismo
11.
Bioconjug Chem ; 35(7): 944-953, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954775

RESUMO

The chemical synthesis of homogeneously ubiquitylated histones is a powerful approach to decipher histone ubiquitylation-dependent epigenetic regulation. Among the various methods, α-halogen ketone-mediated conjugation chemistry has recently been an attractive strategy to generate single-monoubiquitylated histones for biochemical and structural studies. Herein, we report the use of this strategy to prepare not only dual- and even triple-monoubiquitylated histones but also diubiquitin-modified histones. We were surprised to find that the synthetic efficiencies of multi-monoubiquitylated histones were comparable to those of single-monoubiquitylated ones, suggesting that this strategy is highly tolerant to the number of ubiquitin monomers installed onto histones. The facile generation of a series of single-, dual-, and triple-monoubiquitylated H3 proteins enabled us to evaluate the influence of ubiquitylation patterns on the binding of DNA methyltransferase 1 (DNMT1) to nucleosomes. Our study highlights the potential of site-specific conjugation chemistry to generate chemically defined histones for epigenetic studies.


Assuntos
Histonas , Cetonas , Ubiquitinação , Histonas/química , Histonas/metabolismo , Histonas/síntese química , Cetonas/química , Ubiquitina/química , Humanos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/química , Nucleossomos/química , Nucleossomos/metabolismo
13.
Chem Commun (Camb) ; 60(55): 7025-7028, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38888299

RESUMO

We describe a versatile and tuneable thiol responsive linker system using thiovinylketones, which relies on the conjugate addition-elimination mechanism of Michael acceptors for the traceless release of therapeutics. In a proof-of-principle study, we translate our findings to exhibit potent thiol-cleavable antibiotic prodrugs and antibody-drug conjugates.


Assuntos
Liberação Controlada de Fármacos , Imunoconjugados , Pró-Fármacos , Compostos de Sulfidrila , Pró-Fármacos/química , Compostos de Sulfidrila/química , Humanos , Imunoconjugados/química , Antibacterianos/química , Estrutura Molecular , Cetonas/química
14.
Sci Rep ; 14(1): 14146, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898119

RESUMO

Eribulin (ERI), clinically utilized for locally advanced or metastatic breast tumors, has shown potential links to the immune system. Notably, the cGAS-STING pathway, a key component of innate immunity, has gained prominence. Yet, limited reports explore ERI's effects on the cGAS-STING pathway. Additionally, the nuclear presence of cGAS remains poorly understood. This study uniquely delves into ERI's impact on both the cytosolic cGAS-STING pathway and nuclear cGAS. ERI enhances nuclear localization of cGAS, resulting in hyper-activation of the cGAS-STING pathway in triple-negative breast cancer cells. Reduction of cGAS heightened both cell proliferation and ERI sensitivity. In clinical data using ERI in a neo-adjuvant setting, patients with low cGAS cases exhibited reduced likelihood of achieving pathological complete response after ERI treatment. These findings illuminate the potential of cGAS and IFNß as predictive biomarkers for ERI sensitivity, providing valuable insights for personalized breast cancer treatment strategies.


Assuntos
Núcleo Celular , Furanos , Cetonas , Nucleotidiltransferases , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Nucleotidiltransferases/metabolismo , Feminino , Cetonas/farmacologia , Núcleo Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Furanos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Transdução de Sinais/efeitos dos fármacos , Policetídeos de Poliéter
15.
Water Res ; 259: 121866, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38852393

RESUMO

Although unregulated aliphatic disinfection byproducts (DBPs) had a much higher concentration and cytotoxicity than known aromatic DBPs, a recent study indicated that seven classes of regulated and unregulated priority DBPs (one and two-carbon-atom DBPs) just accounted for 16.2% of disinfected water cytotoxicity in the U.S., meaning some of the highly toxic aliphatic DBPs may be overlooked. Haloketones (HKs) are an essential class of priority DBPs with a 1-100 µg/L concentration in drinking water but lack cytotoxicity data. This study investigated the cytotoxicity of seven HKs using Chinese hamster ovary (CHO) cells. The order for cytotoxicity of HKs from most to least toxic was: 1,3-dichloroacetone (LC50: 1.0 ± 0.20 µM) ≈ 1,3-dibromoacetone (1.5 ± 0.19 µM) ≈ bromoacetone (1.9 ± 0.49 µM) > chloroacetone (4.3 ± 0.22 µM) > 1,1,3-trichloropropanone (6.6 ± 0.46 µM) > 1,1,1-trichloroacetone (222 ± 7.7 µM) > hexachloroacetone (3269 ± 344 µM). The cytotoxicity of HKs was higher than most regulated and priority aliphatic DBPs in mono-halogenated, di-halogenated, and tri-halogenated categories. A prediction model of HK cytotoxicity was developed based on the quantitative structure-activity relationship (QSAR), optimizing structures and computing descriptors with Gaussian 09 W. The average concentrations of HKs in representative drinking water samples from South Carolina (U.S.) and Suzhou (China) were 12.4 and 0.9 µg/L, respectively, accounting for 18.8% and 1.7% of their specific total DBPs measured (i.e. not TOX). For South Carolina drinking water, their contributions to total calculated additive cytotoxicity of aliphatic DBPs and overall drinking water cytotoxicity were 86.7% and 14.0%, respectively, demonstrating that HKs are an essential class of overlooked DBPs with a high contribution to drinking water cytotoxicity. Our study can help to explain the conflict that why regulated and priority DBPs (except HKs) just accounted for 16% of chlorinated drinking water cytotoxicity even enough they had much higher concentration and cytotoxicity than known aromatic DBPs.


Assuntos
Cricetulus , Água Potável , Poluentes Químicos da Água , Animais , Células CHO , Poluentes Químicos da Água/toxicidade , Desinfecção , Purificação da Água , Cricetinae , Cetonas/toxicidade , Desinfetantes/toxicidade
16.
Medicine (Baltimore) ; 103(25): e38431, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905365

RESUMO

BACKGROUND: The research focused on the postoperative effect of using interbody fusion cage in lumbar posterior lamina decompression and interbody fusion with pedicle screw by comparing the postoperative effect of using 3D printing (Ti6Al4V) and PEEK material interbody fusion cage. METHODS: Ninety-one patients with lumbar degenerative diseases from the Department of Spine Surgery of Tianjin Hospital were included in the study cohort. They were divided into 3D group (n = 39) and PEEK group (n = 52) according to the use of interbody fusion cage. The imaging data of the patients were collected and the postoperative data of the 2 groups were compared to evaluate patients' health status and the recovery of lumbar structure and function after operation. RESULTS: Combined with the degree of fusion, the clinical effect of 3D printing titanium alloy interbody fusion cage was comprehensively judged. At the last follow-up, the JOA score, ODI index, VAS, prolo function score, and SF-36 scale of the 2 groups showed that the clinical symptoms were better than those before operation (P < .05). The height of intervertebral disc, the area of intervertebral foramen and the physiological curvature of lumbar vertebrae increased in varying degrees after operation (P < .05). At the last follow-up, the vertebral cage fusion rates were as high as 89.13% and 90.91% in the 3D and PEEK groups, with collapse rates of 6.5% and 4.5%, respectively. There were 10 cases of cage displacement in 3D group and 7 cases of cage displacement in PEEK group. There was no significant difference between the 2 groups (P > .05). CONCLUSIONS: In conclusion, 3D printed (Ti6Al4V) interbody fusion cage can obtain good clinical effect in the surgical treatment of lumbar degenerative diseases. Posterior lumbar lamina decompression, bilateral pedicle screw fixation combined with 3D printed cage interbody fusion is excellent in rebuilding the stability of lumbar vertebrae. 3D printed interbody fusion cage can be an ideal substitute material for intervertebral bone grafting. The stable fusion time of interbody fusion cage after lumbar fusion is mostly from 3 months to half a year after operation.


Assuntos
Ligas , Vértebras Lombares , Impressão Tridimensional , Fusão Vertebral , Titânio , Humanos , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Masculino , Vértebras Lombares/cirurgia , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Parafusos Pediculares , Benzofenonas , Polímeros , Idoso , Polietilenoglicóis , Cetonas , Resultado do Tratamento , Descompressão Cirúrgica/métodos , Descompressão Cirúrgica/instrumentação , Adulto , Degeneração do Disco Intervertebral/cirurgia
17.
Carbohydr Res ; 541: 109167, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823063

RESUMO

This paper describes a mild and efficient catalytic deprotection method for isopropylidene ketals and benzylidene acetals using AcOH/H2O/DME(1,2-Dimethoxyethane). The method effectively removes ketal and acetal protecting groups from 2-deoxyglycosides which are prone to hydrolysis under acidic conditions. Moreover, it enables the selective removal of the terminal ketal over an internal one.


Assuntos
Glicosídeos , Glicosídeos/química , Glicosídeos/síntese química , Água/química , Estereoisomerismo , Cetonas/química , Catálise , Acetais/química , Estrutura Molecular
18.
Biosci Rep ; 44(6)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38836325

RESUMO

Natural and synthetic polymeric materials, particularly soft and hard tissue replacements, are paramount in medicine. We prepared calcium-incorporated sulfonated polyether-ether ketone (SPEEK) polymer membranes for bone applications. The bioactivity was higher after 21 days of immersion in simulated body fluid (SBF) due to calcium concentration in the membrane. We present a new biomaterial healing system composed of calcium and sulfonated polyether ether ketone (Ca-SPEEK) that can function as a successful biomaterial without causing inflammation when tested on bone marrow cells. The Ca-SPEEK exhibited 13 ± 0.5% clot with low fibrin mesh formation compared to 21 ± 0.5% in SPEEK. In addition, the Ca-SPEEK showed higher protein adsorption than SPEEK membranes. As an inflammatory response, IL-1 and TNF-α in the case of Ca-SPEEK were lower than those for SPEEK. We found an early regulation of IL-10 in the case of Ca-SPEEK at 6 h, which may be attributed to the down-regulation of the inflammatory markers IL-1 and TNF-α. These results evidence the innovative bioactivity of Ca-SPEEK with low inflammatory response, opening venues for bone applications.


Assuntos
Materiais Biocompatíveis , Células da Medula Óssea , Cálcio , Polímeros , Fator de Necrose Tumoral alfa , Animais , Camundongos , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Polímeros/química , Polímeros/farmacologia , Cálcio/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Benzofenonas/química , Benzofenonas/farmacologia , Inflamação/tratamento farmacológico , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Cetonas/química , Cetonas/farmacologia , Teste de Materiais , Interleucina-1/metabolismo , Interleucina-10/metabolismo
19.
Chemosphere ; 361: 142524, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844103

RESUMO

Covalent Organic Frameworks (COF) having conjugated backbone are an interesting class of metal-free, visible light active, heterogeneous photocatalysts. Interestingly, synthesis of COF using continuous flow process has emerged as an efficient, alternative method when compared to the traditional batch process. Here, we demonstrate the possibility to engineer the physical properties and hence the adsorption and catalytic activities of a ß-ketoenamine COF by varying monomer flow rate and microreactor design during the continuous flow synthesis. Crystallinity of the COF increases on varying the monomer flow rate from 100 (S-100) to 500 (S-500) and up to 1000 µLmin-1 (S-1000), in an S-shaped microreactor, resulting in an enhanced surface area: 525, 722 and 1119 m2g-1 respectively. The photophysical properties of the COF are also found to vary significantly with the change in flow synthesis conditions. S-1000 is characterized by the highest adsorption of MB, due to its high surface area and accessible pores. On the other hand, S-500 shows the highest photocurrent, a low recombination of photogenerated charges and the lowest charge transfer resistance. Thus, S-500 is found to be the best photocatalyst for the removal of a model pollutant (methylene blue, MB). Further, enhanced photocatalytic removal of MB using S-500 could be achieved by performing the photocatalysis in continuous flow.


Assuntos
Estruturas Metalorgânicas , Catálise , Estruturas Metalorgânicas/química , Adsorção , Luz , Processos Fotoquímicos , Poluentes Químicos da Água/química , Aminas/química , Cetonas
20.
Nanoscale ; 16(27): 12934-12946, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38913123

RESUMO

Polyetheretherketone (PEEK), renowned for its exceptional mechanical properties and bio-stability, is considered a promising alternative to traditional metal-based implants. However, the inferior bactericidal activity and the limited angiogenic and osteogenic properties of PEEK remain the three major obstacles to osseointegration in vivo. To overcome these obstacles, in this work, a versatile heterostructured nanocoating was conceived and equipped on PEEK. This nanocoating was designed to endow PEEK with the ability of photo-activated pathogen disinfection, along with enhanced angiogenesis and osteogenesis, effectively addressing the triple-barrier challenge towards osseointegration. The crafted nanocoating, encompassing diverse nutritional metal elements (Fe3+, Mg2+, and Sr2+) and a fusion peptide adept at promoting angiogenesis and osteogenesis, was seamlessly decorated onto PEEK. The engineered implant exhibited an antibacterial activity of over 94% upon near-infrared illumination by virtue of the photothermal conversion of the polyphenol nanocoating. Simultaneously, the decorated hierarchical nanocoatings synergistically promoted cellular adhesion and proliferation and up-regulated angiogenesis-/osteogenesis-associated cytokine expression in endothelial/osteoblast cells, resulting in superior angiogenic differentiation and osteoinductive capability in vitro. Moreover, an in vivo assay in a rabbit femoral defect model revealed that the decorated implant can achieve ameliorative osseointegrative fixation. Collectively, this work offers a practical and instructive clinical strategy to address the triple-barrier challenge associated with PEEK-based implants.


Assuntos
Antibacterianos , Benzofenonas , Osseointegração , Polietilenoglicóis , Polímeros , Animais , Osseointegração/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Coelhos , Polímeros/química , Polímeros/farmacologia , Polietilenoglicóis/química , Humanos , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Peptídeos/química , Peptídeos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana , Cetonas/química , Cetonas/farmacologia , Proliferação de Células/efeitos dos fármacos , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos
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