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Multitargeting kinase inhibitors recently proved to be a profitable approach for conquering cancer proliferation. The current study represents the design and synthesis of new thiophene, thienopyridine, and thiazoline-based derivatives 4-14a,b. All the target compounds were examined in vitro against three cancer cell lines; the liver (HepG-2), breast (MCF-7), and colon (HCT-116) where the thiophene-based compounds 5a-c, demonstrated the most potent activity. Furthermore, the latter derivatives revealed a safety profile against WI-38 normal cell line of selectivity indices ranging from 4.43 to 17.44. In vitro enzyme assay of 5a-c revealed that the carbohydrazide analog 5c has the most promising multitargeting inhibiting activity against Pim-1, VEGFR-2, and EGFRWT enzymes of IC50 values; 0.037 ± 0.02, 0.95 ± 0.24, and 0.16 ± 0.05 µM, respectively. As it was the most potent analog, 5c was further subjected to cell cycle and apoptosis analysis. The results indicated that it induced preG1 arrest and an apoptotic effect in the early and late stages. Moreover, further apoptosis studies were carried out for 5c to evaluate its proapoptotic potential. Interestingly, 5c enhanced the levels of Bax/Bcl-2 ratio, p53, and active caspase 3 by 18, 6.4, and 24 folds, respectively compared to the untreated cells. The antimicrobial evaluation showed that only compounds 3 and 5a produced broad-spectrum potency, while 5b and 5c exhibited outstanding antifungal effects. Finally, a molecular docking study was carried out to discover the probable interactions of compound 5c with the active sites of Pim-1, VEGFR-2, and EGFRWT kinases.
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Antineoplásicos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases , Relação Estrutura-Atividade , Tienopiridinas/farmacologia , Tiofenos/químicaRESUMO
The supper dissemination of antibiotic waste in water resources has exponentially progressed the vital water and soil pollution that affect human health and the environment. Consequently, there have been several types of research anticipated for the green mineralization of such pollutants. Herein, we intended a surfactant-aided sol-gel formation of lanthanum-doped sodium tantalate (LNTO) nanocrystals. The synthesized 13 nm averaged-size perovskite LNTO nanocrystals were responsive to visible-light irradiation by incorporation of 4.4-5.2 nm oxide nanoparticles, namely Bi2O3, CdO, Fe2O3, and CuO at 4.0 wt% through coprecipitation. The formed nanomaterials unveiled mesostructured surface textures with specific surface areas of 199-229 m2 g-1. The obtained nanoceramics were employed for the mineralization of 10 ppm of ciprofloxacin antibiotic (CPF) as an emerging antibiotic waste in water under visible light irradiation. The CuO-incorporated LNTO exhibited the best photocatalytic oxidation of CPF after 120 min compared with other oxides with an excellent photoreaction rate of 0.0343 min-1 which is 49 times higher than the pure LNTO. The 2.0 gL-1 CuO/LNTO-dose achieved the full photooxidation of CPF at an oxidation speed of 0.0738 min -1 within just 1.0 h of visible light irradiation and magnificent regeneration ability. This enhanced activity of CuO/LNTO is regarded as significant light absorption and a bandgap energy reduction to 2.12 eV. Besides that, the heterojunction between CuO and LNTO amended the photogenerated carrier mobility and separation as concluded from the photoluminescence and photocurrent exploration. This comparative work suggests the proper design of low bandgap oxide decoration of solution-based perovskite oxide photocatalysts for promoting the visible-light mineralization of antibiotics in water.
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Ciprofloxacina , Nanopartículas , Antibacterianos , Catálise , Humanos , Luz , Nanopartículas/química , Óxidos/química , Água/químicaRESUMO
This study was focused on the synthesis of new pyrimidines 4a,b, 5a,b and pyrazoles 6a, b as ATP mimicking tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR). The new compounds were assessed as cytotoxic candidates against human breast cancer cells (MCF-7) and hepatocellular carcinoma cells (HepG-2). All the new compounds appeared as more potent cytotoxic agents than erlotinib, while only compound 4a exhibited more potency than 5-flourouracil and 4b analogue was equipotent to it. Accordingly, the kinase suppression effect of 4a and 4b was further evaluated against EGFRWT, EGFRL858R and EGFRT790M. Both pyrimidine analogues 4a and 4b displayed outstanding inhibitory activity against EGFRWT and its two mutated isoforms EGFRL858R and EGFRT790M in comparing to erlotinib and osimertinib as reference drugs. Additionally, all the new analogues were subjected to antimicrobial assay. Interestingly, both 4a and 4b represented the most promising activity of wide spectrum antimicrobial effect against the examined microbes in comparison to gentamycin and ketoconazole as standard drugs. Moreover, docking results proved the good binding interactions of the compounds 4a and 4b with EGFRWT and EGFRT790M which were in accordance with the results of the in vitro enzyme assay. Additional in silico ADMET studies were performed for the new derivatives which represented their good oral absorption, good drug-likeness properties and low toxicity risks in human.
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Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Aspergillus fumigatus/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Mucorales/efeitos dos fármacos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteus vulgaris/efeitos dos fármacos , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Streptococcus/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Vitamin D is critical for bone physiology. In this study, we quantified Vitamin D Binding Protein (VitDBP) levels in saliva as a measure of Vitamin D during orthodontic tooth movement. METHODS: In this longitudinal study, saliva samples were collected from 73 orthodontic patients for 4 timepoints for the first six months of orthodontic treatment, along with dental casts at the beginning and the end of the study period. The saliva was measured for VitDBP as a biological marker for bone apposition and clinical tooth movement. We used the absolute change in Little's Irregularity Index as a quantitative measure for alignment. In addition, we measured the levels of alkaline phosphatase (ALP) in saliva as a marker of bone turnover. RESULTS: Both low (< 2.75 ng/ml) and high (> 6.48 ng/ml) VitDBP levels were associated with reduced tooth movement. Significant (p < 0.05) seasonal changes in VitDBP using a two-season year model were found with lower levels observed in the summer (Apr-Sept) than in the winter (Oct-Mar). CONCLUSIONS: Clinically significant orthodontic tooth movement is associated with an optimal range of VitDBP in saliva. Normal levels of VitDBP correlated with more orthodontic tooth movement, suggesting a "normal" range of salivary content of VitDBP. Given the strong trend that is independent of the confounding factors (ex. age, race or gender), the predictive value or salivary VitDBP for tooth movement should be studied in larger cohorts in future studies.
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Técnicas de Movimentação Dentária , Proteína de Ligação a Vitamina D , Remodelação Óssea , Humanos , Estudos Longitudinais , SalivaRESUMO
The addition of 2,6-dimethylphenyl isocyanide and t-butyl isocyanide to tetramesityldisilene was examined. In both cases, the initially formed product is an iminodisilirane; however, the iminodisiliranes are unstable under the reaction conditions and react with a second equivalent of the isocyanide to give either a 3-silaazetidine or a novel bicyclic double enamine, respectively. Taken together with the previous examples in the literature, the results demonstrate that subtle differences in the steric bulk of the disilene or the electronic effects of the isocyanide can lead to dramatic differences in the reaction pathway.
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The reaction of benzyl isocyanide, tert-butyl isocyanide, and 2,6-dimethylphenyl isocyanide with tetramesityldigermene (Mes2 Ge=GeMes2 ) was examined. Whereas the addition of benzyl isocyanide gave the C-NC activation product, Mes2 Ge(CH2 Ph)Ge(CN)Mes2 , tert-butyl isocyanide, and 2,6-dimethylphenyl isocyanide did not give stable adducts, rather the rate of conversion of the digermene to the corresponding cyclotrigermane was accelerated. A comparison between the reactivity of the isocyanides with Mes2 Ge=GeMes2 and the Ge(100)-2×1 surface was made and some insights into the surface chemistry are offered.
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The addition of nitromethane to tetramesityldisilene and tetramesityldigermene leads to the formation of the novel 1,3,2,4,5-dioxazadisil- and digermolidine ring systems, respectively. The 1,3,2,4,5-dioxazadisilolidine isomerizes to the 1,4,2,3,5-dioxazadisilolidine ring system, whereas the 1,3,2,4,5-dioxazadigermolidine undergoes ring opening to the isomeric oxime. The preferential formation of the 1,3,2,4,5-dioxazadisilolidine, and its rearrangement to a 1,4,2,3,5-dioxazadisilolidine, provides support for the suggested reaction pathway between nitromethane and the Si(100) 2×1 reconstructed surface.
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Introduction: Gonial angle is an important craniofacial parameter providing information about symmetry and vertical dimensions of the facial skeleton. It can be measured on panoramic radiographs and lateral cephalograms. Reliable assessment of the gonial angle is challenged by the superimpositions associated with lateral cephalograms. The aim of the current study was to assess the precision of panoramic imaging in measuring the gonial angles compared to lateral cephalograms in adult patients with different mandibular divergence patterns. Methods: Panoramic radiographs and lateral cephalograms of 448 adults (18-30 years old) were utilized in the study. The gonial angle was determined on the lateral cephalograms using an online AI-driven assessment tool (WebCephTM) and compared to the panoramic measurements among the different gender, malocclusion, and mandibular divergence groups. Results: Statistically significant differences were recorded between measurements taken on lateral cephalograms or panoramic radiographs (p=0.022). In addition, statistically significant differences were reported in gonial angle measurements on panoramic radiographs among the different mandibular divergence groups (p=0.004) for FMA (p=0.002) for Sn-GoMe. Conclusion: While cephalometry is considered the gold standard tool for reliable gonial angle assessment, panoramic radiographs were more accurate in detecting the differences between the divergence groups in the current study.
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Silver nanoparticles were successfully incorporated into a melamine-based polymer, resulting in the synthesis of (Ag NPs@Bipy-PAN) through a reverse double solvent approach. The synthesised Ag NPs@Bipy-PAN polymer underwent extensive characterisation through Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy and Energy Dispersive X-ray (EDX) and Thermal Gravimetric Analysis. PXRD analysis confirmed the successful encapsulation of Ag nanoparticles and provided insights into the amorphous nature of the polymer following encapsulation. SEM and EDX analyses further corroborated the presence and distribution of Ag nanoparticles on the polymer surface. The biological efficacy of the Ag NPs@Bipy-PAN polymer was evaluated through antibacterial, anti-breast cancer, and biocompatibility assays. The results demonstrated notable antibacterial and anticancer activities, with significant efficacy against bacterial strains and breast cancer cells. Biocompatibility assessments indicated acceptable compatibility, particularly at a concentration of 2.5 mg/mL, compared to untreated control cells. These findings suggest that Ag NPs@Bipy-PAN has considerable potential as a candidate for cancer-targeted and antimicrobial drug delivery systems. The incorporation of silver nanoparticles into the melamine-based polymer enhances the safety profile of these systems in in vivo conditions, making them a viable option for advanced therapeutic applications.
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Antibacterianos , Antineoplásicos , Nanopartículas Metálicas , Prata , Triazinas , Prata/química , Prata/farmacologia , Triazinas/química , Triazinas/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas Metálicas/química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Testes de Sensibilidade Microbiana , Células MCF-7 , Feminino , Polímeros/química , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Difração de Raios XRESUMO
The pursuit of developing sensors, characterized by their fluorescence-intensity enhancement or "turn-on" behavior, for accurately detecting noxious small molecules, such as amines, at minimal levels remains a significant challenge. Metal-organic frameworks (MOFs) have emerged as promising candidates as sensors as a result of their diverse structural features and tunable properties. This study introduces the rational synthesis of a new highly coordinated (6,12)-connected rare earth (RE) alb-MOF-3, by combining the nonanuclear 12-connected hexagonal prismatic building units, [RE9(µ3-O)2(µ3-X)12(OH)2(H2O)7(O2C-)12], with the 6-connected rigid trigonal prismatic extended triptycene ligand. The resulting Y-alb-MOF-3 material is distinguished by its high microporosity and Brunauer-Emmett-Teller surface area of approximately 1282 m2/g, which offers notable hydrolytic stability. Remarkably, it demonstrates selective detection capabilities for primary aliphatic amines in aqueous media, as evidenced by fluorescence turn-on behavior and photoluminescence (PL) titration measurements. This work emphasizes the potential of MOFs as sensors in advancing their selectivity and sensitivity toward various analytes.
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In this work, palladium nanoparticles, supported by polyaminals (Pd@PAN-NA), were synthesized via a reverse double solvent approach and used as a nano catalyst. The thermogravimetric and the elemental analysis revealed that the catalyst had good dispersity and improved thermal stability. The catalytic activity of the prepared Pd@PAN-NA catalyst was studied for a methylene blue chemical reaction in the presence of NaBH4 as a reducing agent. The effect of the catalyst dose, pH, and dye initial concentration were examined to optimize the chemical reduction conditions. The prepared catalyst Pd@PAN-NA removed 99.8% of methylene blue organic dye, indicating its potential effect for treating waste and contaminated water.
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This study aimed to evaluate the clinical outcomes and the frequency of return to sport after the arthroscopic repair of a humeral avulsion of the inferior glenohumeral ligament (HAGL) lesion. Web of Science, Scopus, and Medline via PubMed and OVID were searched to identify the relevant citations. Screening and data extraction were performed independently. The Comprehensive Meta-Analysis software was used for all statistical analyses (CMA; USA version 3.3.070). A total of 18 articles (n = 832 patients; of whom, 379 patients had HAGL) were included. The fixed-effect estimate showed that the percentage of patients who returned to their sports was 89.1% (95% CI = 85% to 92.2%). The mean duration to return was estimated to be 6.65 months (95% CI = 5.10 to 8.20). Postoperatively, the mean Western Ontario Shoulder Instability Index (WOSI), Oxford Shoulder Instability Score (OSIS), and Subjective Shoulder Value (SSV) scores were 88.60 (95% CI = 86.18 to 90.98), 15.02 (95% CI = 7.42 to 22.63), and 86.90 (95% CI = 80.79 to 93.00), respectively. The Rowe score improved significantly postoperatively with a mean difference (MD) of 54.47 (95% CI = 39.28 to 69.66). The University of California - Los Angeles (UCLA) shoulder score increased significantly post-arthroscopic repair (MD = 10.91, 95% CI = 10.07 to 11.76). The current evidence suggests that arthroscopic repair of HAGL lesions is associated with a high percentage of return to sports and improved Rowe score, WOSI, UCLA shoulder score, OSIS scale, and SSV score. The quality of the included studies is moderate; however, these findings are promising and call for further multicenter, prospective studies.
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OBJECTIVE: This study aims to identify the motivations behind orthodontic re-treatment in Saudi Arabia. MATERIALS AND METHODS: This is a cross-sectional study performed through a patient questionnaire. The questionnaire elicited data on the respondents' socio-demographic data, type of previous orthodontic treatment, retention, satisfaction level, and reasons for undergoing orthodontic re-treatment. RESULTS: Four hundred and nineteen responses were received during the study period from June to July 2022. The result showed a pre-dominant female predilection (83, 29%), with the majority belonging to the 21-25 age group (47.26%). Most participants had had one previous orthodontic treatment (77%), with an active treatment time of approximately 1-3 years (55.85%). There was no significant difference between the satisfaction of outcomes after the initial treatment and at the time of the survey. Most participants received retention appliances (69.45%) and were informed about the importance of appliances. The type of retention was mainly removable retainers (47.5%). Around one-third of the sample (31.98%) were interested in seeking orthodontic re-treatment, with self-motivation as the primary drive and improving the smile as the predominant reason. CONCLUSION: The study's findings show that a large portion of the population is seeking orthodontic re-treatment, which must be considered. Self-motivation was a driving force rather than external motivation. The most common reason for seeking orthodontic re-treatment was to improve their smile and the increased esthetic demand.
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Studying the effect of functional groups on the porosity structure and adsorption efficiency of polymer materials is becoming increasingly interesting. In this work, a novel porous polyaminal-linked polymer, based on naphthalene and melamine (PAN-NA) building blocks, was successfully synthesized by a one-pot polycondensation method, and used as an adsorbent for both CO2 and heavy metals. Fourier transform infrared spectroscopy, solid-state 13 C NMR, powder X-ray diffraction, and thermogravimetry were used to characterize the prepared polymer. The porous material structure was established by field-emission scanning electron microscope and N2 adsorption-desorption methods at 77 K. The polymer exhibited excellent uptake of CO2, 133 mg/g at 273 K and 1 bar. In addition, the adsorption behavior of PAN-NA for different metal cations, including Pb(II), Cr(III), Cu(II), Cd(II), Ni(II), and Ba(II), was investigated; a significant adsorption selectivity toward the Pb(II) cation was detected. The influence of pH, adsorbent dose, initial concentrations, and contact time was also assessed. Our results prove that the introduction of naphthalene in the polymer network improves the porosity and, thus, CO2 adsorption, as well as the adsorption of heavy metals.
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BiVO4 has been constructed into heterojunctions with TiO2 to boost the photocatalytic ability under visible illumination. Here, mesoporous BiVO4/TiO2 nanocomposites have been fabricated by a facile sol-gel approach utilizing nonionic surfactant and addressed for morphological, optical, structural, and degradation of ciprofloxacin (CIP) in water under visible illumination as an antibiotic pollutant model. The TEM images demonstrated that the TiO2 NPs are homogenous in terms of shape and size (15 ± 5 nm). The introduction of BiVO4 into mesoporous TiO2 could effectively enhance the rapid separation efficiency of the photoinduced carriers and optical absorption. The 3%BiVO4/TiO2 photocatalyst possessed the best degradation efficiency (100%) within 60 min which was promoted 20-folds larger than TiO2 NPs (5%). 3%BiVO4/TiO2 nanocomposite exhibited the fastest degradation rate (2.15 × 10-2 min-1), which was 40 times faster than bare TiO2 photocatalyst (0.05 × 10-2 min-1). The enhanced photocatalytic ability originated from superior charge separation characteristics and high solar energy absorption in mesopore structures. The recombination rate and mobility of charge carriers were characterized utilizing photoluminescence (PL) and photoelectrochemical measurements. This work highlights the advantages of mesoporous heterojunction BiVO4/TiO2 nanocomposites for photocatalytic performances and provides a multilateral route to design an effective wide-spectrum response photocatalyst for the development of comparable materials. The photocatalytic mechanism for degradation CIP over BiVO4/TiO2 was discussed in detail..
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Poluentes Ambientais , Vanadatos , Fotólise , Vanadatos/química , Bismuto/química , Catálise , Ciprofloxacina/química , Antibacterianos/química , Água , TensoativosRESUMO
The response to the high demand for decreasing the amount of CO2 in the atmosphere, a new polyaminal-based polymer network was designed and successfully prepared through one-pot polycondensation reaction of melamine and [2,2'-Bipyridine]-5,5'-dicarbaldehyde. The formation of the polymer structure was confirmed by FT-IR, solid-state 13C NMR, and powder-X-ray diffraction. The porous properties of the polymeric structure were confirmed by field-emission scanning electron microscope and N2 adsorption-desorption methods at 77 K. The prepared polymer can take up 1.02 mmol/g and 0.71 mmol/g CO2 at 273 K and 298 K, respectively, despite its relatively modest Brunauer-Emmett-Teller (BET) surface area (160.7 m2/g), due to the existence of superabundant polar groups on the pore surfaces.
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Deregulation of various protein kinases is considered as one of the important factors resulting in cancer development and metastasis, thus multi-targeting the kinase family is one of the most important strategies in current cancer therapy. This context represents the design and synthesis of two sets of derivatives bearing a pyrazoline-3-one ring conjugated either with a thieno[3,2-d]thiazole or with a dihydrothiazolo[4,5-d]thiazole scaffold via an NH linker, 3a-d and 5a-d respectively, using the pyrazolinone-thiazolinone derivative 1 as a key precursor. All the newly synthesized compounds were assessed in vitro for their anticancer activity against two cancer cell lines (MCF-7 and HepG-2). The safety profile of the most active cytotoxic candidates 1 and 3c was further examined against the normal cell line WI-38. The compounds 1 and 3c were further evaluated as multi-targeting kinase inhibitors against EGFR, VEGFR-2 and BRAFV600E, exhibiting promising suppression impact. Additionally, the latter compounds were investigated for their impact on cell cycle and apoptosis induction potential in the MCF-7 cell line. Moreover, the antimicrobial activity of all the new analogues was evaluated against a panel of Gram-positive and Gram-negative bacteria, yeast and fungi in comparison to streptomycin and amphotericin-B as reference drugs. Interestingly, both 1 and 3c showed the most promising microbial inhibitory effect. Molecular docking studies showed promising binding patterns of the compounds 1 and 3c with the prospective targets, EGFR, VEGFR-2 and BRAFV600E. Finally, additional toxicity studies were performed for the new derivatives which showed their good drug-like properties and low toxicity risks in humans.
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New synergic behavior is always inspiring scientists toward the formation of nanocomposites aiming at getting advanced materials with superior performance and/or novel properties. Carbon nanotubes (CNT), graphene, fullerene, and graphite as carbon-based are great fillers for polymeric materials. The presence of these materials in the polymeric matrix would render it several characteristics, such as electrical and thermal conductivity, magnetic, mechanical, and as sensor materials for pressure and other environmental changes. This review presents the most recent works in the use of CNT, graphene, fullerene, and graphite as filler in different polymeric matrixes. The primary emphasis of this review is on CNT preparation and its composites formation, while others carbon-based nano-fillers are also introduced. The methods of making polymer nanocomposites using these fillers and their impact on the properties obtained are also presented and discussed.
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A new class of biologically active polymer nanocomposites based on polyvinyl alcohol and reinforced mixed graphene/carbon nanotube as carbon-based nanofillers with a general abbreviation (polyvinyl alcohol/mixed graphene-carbon nanotubes) has been successfully synthesized by an efficient solution mixing method with the help of ultrasonic radiation. Mixed graphene and carbon nanotubes ratio has been prepared (50%:50%) wt by wt. Different loading of mixed graphene-carbon nanotubes (2, 5, 10, 15, and 20 wt%) were added to the host polyvinyl alcohol polymer. In this study, polyvinyl alcohol/mixed graphene-carbon nanotubesa-e nanocomposites were characterized and analyzed by X-ray diffraction, Fourier transform infrared, scanning electron microscopy, transmission electron microscopy, and the thermal stability was measured by thermogravimetric analysis and derivative thermal gravimetric. Fourier transform infrared and X-ray diffraction spectra proved the addition of mixed graphene-carbon nanotubes into polyvinyl alcohol matrix. X-ray diffraction patterns for these nanocomposites showed 2θ = 19.35° and 40° due to the crystal nature of polyvinyl alcohol in addition to 2θ = 26.5° which attributed to the graphite plane of carbon-based nanofillers. Thermal stability of polyvinyl alcohol/mixed graphene-carbon nanotubes nanocomposites was enhanced comparing with pure polyvinyl alcohol. The main degradation step ranged between 360° and 450°C. Moreover, maximum composite degradation temperature has appeared at range from 285°C to 267°C and final composite degradation temperature (FCDT) displayed at a temperature range of 469-491°C. Antibacterial property of polyvinyl alcohol/mixed graphene-carbon nanotubesa-e nanocomposites were tested against Escherichia coli bacteria using the colony forming units technique. Results showed an improvement of antibacterial property. The rate percentages of polyvinyl alcohol/mixed graphene-carbon nanotubesb, polyvinyl alcohol/mixed graphene-carbon nanotubesc, and polyvinyl alcohol/mixed graphene-carbon nanotubesd nanocomposites after 24 h are 6%, 5%, and 7% respectively. However, polyvinyl alcohol/mixed graphene-carbon nanotubese nanocomposite showed hyperactivity, where its reduction percentage remarkably raised up to 100% which is the highest inhibition rate percentage. In addition, polyvinyl alcohol and polyvinyl alcohol/graphene-carbon nanotubesa-d showed colony forming units values/ml 70 × 106 and 65 ± 2 × 106 after 12 h. After 24 h, the colony forming units values/ml were in the range of 86 × 106-95 × 106.
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The addition of a variety of sulfones and a sulfoxide to ditetrelenes (a disilene and a digermene) was examined. The reaction of benzenesulfonyl chloride with tetramesityldisilene or tetramesityldigermene results in the formation of the 1,2-addition products, 2-chlorotetramesityldisilyl- or digermylbenzenesulfinate. The addition of p-toluenesulfonyl chloride to the disilene gave the analogous product, 2-chlorotetramesityldisilyl p-toluenesulfinate. In contrast, benzenesulfonyl fluoride, diphenyl and dimethyl sulfone did not react with either the disilene or the digermene. The unprecedented formation of the sulfinates reveals a selective 2-electron reduction of the sulfur centres using ditetrelenes. The addition reactions of sulfonyl compounds illustrates the potential of ditetrelenes to serve as reducing agents which react rapidly, at room temperature under mild conditions. The reaction of tetramesityldisilene with diphenyl sulfoxide resulted in the formation of tetramesityloxadisilirane and with benzene sulfonic acid resulted in the formation of 1,1,2,2-tetramesityldisilyl benzenesulfonate.