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1.
Chem Commun (Camb) ; 60(30): 4002-4014, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38451211

RESUMO

Application of the borrowing hydrogen strategy facilitates utilization of abundantly available alcohols for linear or branched long-chain alcohols. Selective synthesis of such alcohols is highly challenging and involves the utilization of transition metal catalysts towards the desired cross-coupled product. Herein, we have highlighted recent advances (from 2015 to 2023) towards the synthesis of higher alcohols. Major focus has been given to the development of ligands, including transition metal catalysts. Judicious catalyst design plays a key role in the alkylation process and is summarised in this review.

2.
J Cancer Res Ther ; 20(1): 1-8, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554291

RESUMO

Thyroid carcinoma is the most common malignancy of the endocrine system and accounts for nearly 1.5% of all new cancer cases in India. The incidence of thyroid cancers is on the rise secondary to multiple factors including the widespread use of radiological imaging. Surgery remains the cornerstone of treatment, and radioactive iodine therapy plays a pivotal role in differentiated thyroid cancer. Radiation therapy appears to be an underutilized treatment modality. In this review, we have summarized the role of radiation in the treatment of thyroid cancer.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Humanos , Adenocarcinoma/radioterapia , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/patologia
3.
J Egypt Natl Canc Inst ; 36(1): 4, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38311646

RESUMO

BACKGROUND: Esophageal cancer has a poor survival outcome with 5-year OS at 16.7% despite treatment. Some inflammation-based prognostic indicators like the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been previously studied as potential biomarker for predicting outcome in esophageal cancer. Recently, platelet-to-albumin ratio (PAR) has been reported as a promising prognostic factor in gastrointestinal malignancies. METHODS: We performed a retrospective analysis of prospectively treated patients of carcinoma esophagus to evaluate the prognostic significance of inflammation-based prognostic indicators-neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and a composite inflammation-nutrition index: platelet-to-albumin ratio (PAR) in esophageal cancer. Based on previous studies, the optimal cut-off value of PAR was kept at 5.7 × 10^9, and 2.62 for NLR. RESULTS: A total of 71 patients of locally advanced esophageal cancer treated between 2019 and 2022, with either neoadjuvant or definitive chemoradiotherapy, were included. Median follow-up time was 19 months [range: 7-44 months]. Median OS and PFS in our study cohort were 11.3 months [range: 7-23 months] and 7.8 months [range: 3-17 months], respectively. In univariate analysis, lower PAR was found to be significantly correlated with shorter survival time (HR = 2.41; 1.3-4.76; p = 0.047). There was no association found between the OS and the NLR [HR = 1.09; 0.95-1.26; p = 0.222]. Univariate and multivariate linear and logistic regressions found no association between V15, V10, V5, or V2 of spleen and nadir lymphocyte count or between Dmax or Dmean and nadir lymphocyte counts. CONCLUSION: Present analysis found a trend toward an inverse association between PAR and OS. PAR, in the not-so-distant future, may evolve as a novel, convenient, and inexpensive prognostic indicator in esophageal cancer.


Assuntos
Neoplasias Esofágicas , Linfopenia , Humanos , Prognóstico , Estudos Retrospectivos , Linfócitos/patologia , Biomarcadores , Linfopenia/diagnóstico , Linfopenia/etiologia , Linfopenia/patologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/radioterapia , Inflamação/patologia
4.
Environ Sci Pollut Res Int ; 31(4): 5457-5472, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123767

RESUMO

The application of green synthesized nanocomposites for the prevention of environmental pollution is increasing nowadays. Here, a green composite has been synthesized by embedding MnO2 on Rauvolfia tetraphylla leaves using its leaf extract hereinafter termed as MnO2@RTL, and demonstrated for crystal violet (CV) dye removal from simulated and real wastewater. The surface properties of the material were determined by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), and Brunauer-Emmet-Teller (BET) surface area, pHZPC, and zeta potential. The material exhibits a remarkable adsorption capacity of 61.162 mg/g at 328 K and pH 7. The adsorption was best fitted with Pseudo-second-order kinetic (R2 = 0.998) and a combination of Langmuir and Freundlich isotherm model (R2 = 0.994-0.999). The thermodynamic study revealed spontaneous (ΔG values = - 2.988 to - 4.978 kJ/mol) and endothermic (ΔH values = 6.830 to 11.018 kJ/mol) adsorption. After adsorption, 80% regeneration occurred with 50% methanol, and recycled up to five times. Advantageously, the material was able to remove CV dye in the presence of coexistent ions and from industrial wastewater, confirming field applicability. The adsorption capacity of the material is superior to previously reported materials. The standard deviation and relative standard deviations have been evaluated to be 0.000422-0.000667 and 0.473-0.749%, which suggests the reliability of the experiments. The exhausted material, after recycling, was pyrolyzed to overcome the disposal problem. It was established as a secondary adsorbent with 73% efficiency which makes the material win-win. The material showed antibacterial properties with Staphylococcus aureus bacteria with a zone of inhibition 5 mm.


Assuntos
Rauwolfia , Poluentes Químicos da Água , Águas Residuárias , Violeta Genciana , Antibacterianos/farmacologia , Compostos de Manganês , Reprodutibilidade dos Testes , Óxidos , Termodinâmica , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Am Chem Soc ; 145(49): 27103-27112, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38051543

RESUMO

Nature's design of biological ion channels that demonstrates efficient gating and selectivity brings to light a very promising model to mimic and design for achieving selective and tunable ion transport. Functionalized nanopores that permit modulation of the pore wall charges are a compelling approach to gain control over the ion transport mechanism through the pores. This makes way for employing a noncovalent supramolecular approach for attaining charge reversal of the MOF pore walls using donor-acceptor pairs that can demonstrate strong charge transfer interactions. Herein, robust Zr4+-based mesoporous MOF-808 was postsynthetically modified into an anion-selective nanochannel (MOF-808-MV) by modification with dicationic viologen-based motifs. Charge modulation and even reversal of the MOF-808-MV pore walls were then explored taking advantage of strong charge transfer interactions between the grafted dicationic viologen acceptor moieties and anionic, π-electron-rich donor guest molecules such as pyranine (PYR) and tetrathiafulvalene tetrabenzoic acid (TTF-TA). Tunability of the MOF pore charge from positive to neutral to negative was achieved via simple methodologies such as diffusion control in case of guest molecule like PYR and by pH modulation for pH-responsive guest like TTF-TA. This results in a concomitant modulation in the selectivity of the nanochannel, rendering it from anion-selective to ambipolar to cation-selective. Furthermore, as a real-time application of this ion channel, Na+ ion conductivity (σ = 3.5 × 10-5 S cm-1) was studied at ambient temperature.

6.
ACS Omega ; 8(31): 28002-28025, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37576662

RESUMO

Porous structures with sizes between the submicrometer and nanometer scales can be produced using efficient and adaptable electrospinning technology. However, to approximate desirable structures, the construction lacks mechanical sophistication and conformance and requires three-dimensional solitary or multifunctional structures. The diversity of high-performance polymers and blends has enabled the creation of several porous structural conformations for applications in advanced materials science, particularly in biomedicine. Two promising technologies can be combined, such as electrospinning with 3D printing or additive manufacturing, thereby providing a straightforward yet flexible technique for digitally controlled shape-morphing fabrication. The hierarchical integration of configurations is used to imprint complex shapes and patterns onto mesostructured, stimulus-responsive electrospun fabrics. This technique controls the internal stresses caused by the swelling/contraction mismatch in the in-plane and interlayer regions, which, in turn, controls the morphological characteristics of the electrospun membranes. Major innovations in 3D printing, along with additive manufacturing, have led to the production of materials and scaffold systems for tactile and wearable sensors, filtration structures, sensors for structural health monitoring, tissue engineering, biomedical scaffolds, and optical patterning. This review discusses the synergy between 3D printing and electrospinning as a constituent of specific microfabrication methods for quick structural prototypes that are expected to advance into next-generation constructs. Furthermore, individual techniques, their process parameters, and how the fabricated novel structures are applied holistically in the biomedical field have never been discussed in the literature. In summary, this review offers novel insights into the use of electrospinning and 3D printing as well as their integration for cutting-edge applications in the biomedical field.

7.
RSC Adv ; 13(27): 18568-18604, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37346946

RESUMO

Water is an indispensable part of human life that affects health and food intake. Water pollution caused by rapid industrialization, agriculture, and other human activities affects humanity. Therefore, researchers are prudent and cautious regarding the use of novel materials and technologies for wastewater remediation. Graphdiyne (GDY), an emerging 2D nanomaterial, shows promise in this direction. Graphdiyne has a highly symmetrical π-conjugated structure consisting of uniformly distributed pores; hence, it is favorable for applications such as oil-water separation and organic-pollutant removal. The acetylenic linkage in GDY can strongly interact with metal ions, rendering GDY applicable to heavy-metal adsorption. In addition, GDY membranes that exhibit 100% salt rejection at certain pressures are potential candidates for wastewater treatment and water reuse via desalination. This review provides deep insights into the structure, properties, and synthesis methods of GDY, owing to which it is a unique, promising material. In the latter half of the article, various applications of GDY in desalination and wastewater treatment have been detailed. Finally, the prospects of these materials have been discussed succinctly.

9.
J Org Chem ; 88(11): 7162-7171, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37161856

RESUMO

Herein, we have demonstrated a simple nickel-catalyzed C-3-selective alkylation of 2-oxindoles using a wide variety of secondary alkyl alcohols. As a special highlight, functionalization of the cholesterol derivative was reported. Control experiments, initial mechanistic studies, and deuterium-labeling experiments were performed for the alkylation process.

10.
Chem Commun (Camb) ; 59(12): 1569-1588, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36655919

RESUMO

Metal-organic frameworks (MOFs, also known as porous coordination polymers or PCPs) are a novel class of crystalline porous material. The tailorable porous structure, in terms of size, geometry and function, has attracted the attention of researchers across all disciplines of materials science. One of the many exciting aspects of MOFs is that through directional and reversible coordination bonding, organic linkers (chromophores with metal-coordinating functional groups) and metal ions (and clusters) can be spatially organized in a preconceived geometry. The well-defined spatial geometry of the metals and linkers is very advantageous for optoelectronic functions (solar cells, light-emitting diodes, photocatalysts) of the materials. This feature article evaluates the scope of charge transfer (CT) interactions in MOFs, involving the organic linkers and metal ion or cluster components. Irrespective of the type (size, shape, electronic property) of organic chromophores involved, MOFs provide an insightful path to design and make the CT process efficient. The selected examples of MOFs with CT characteristics do not only illustrate the design principles but render a pathway towards understanding the complex photophysical processes and implementing those for future optoelectronic and catalytic applications.

11.
J Trace Elem Med Biol ; 75: 127107, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36427436

RESUMO

BACKGROUND: Increased incidence of antibiotic-resistant species calls for development of new types of nano-medicine that can be used for healing of bacteria-caused wounds, such as diabetic foot ulcer. As diabetic patients have inefficient defense mechanism against reactive oxygen species (ROS) produced in our body as a by-product of oxygen reduction, the process of wound healing takes longer epithelialisation period. Ceria nanoparticles (CNPs) are well-known for their antibacterial and ROS-scavenging nature. Yet till now no significant effort has been made to conjugate ceria nanoparticles with drugs to treat diabetic wounds. METHODS: In this experiment, CNPs were synthesized in-house and clindamycin hydrochloride was loaded onto it by physical adsorption method for reactive oxygen species responsive drug delivery. Various physico-chemical characterisations such as Transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Energy dispersive X-ray, Thermogravimetric study etc. were performed to affirm the formation of both nanoceria along with drug encapsulated nanoceria. RESULTS: Both of these as-prepared formulations inhibited the growth of Gram-positive as well as Gram-negative bacteria confirmed by Disk diffusion study; exhibiting their antibacterial effect. In-vitro drug release study was carried out in physiological environment both in absence and presence of hydrogen peroxide solution to test the reactive ROS-responsiveness of the drug loaded nanocomposites. It also exhibited faster wound healing in diabetes-induced rats. Therefore, it could successfully lower the amount of serum glucose level, inflammation cytokines, hepatotoxic and oxidative stress markers in diabetic rats as confirmed by various ex vivo tests conducted. CONCLUSION: Thus, drug loaded ceria nanoparticles have the potential to heal diabetic wounds successfully and can be considered to be useful for the fabrication of appropriate medicated suppositories beneficial for diabetic foot ulcer treatment in future.


Assuntos
Diabetes Mellitus Experimental , Pé Diabético , Ratos , Animais , Clindamicina/farmacologia , Clindamicina/uso terapêutico , Pé Diabético/tratamento farmacológico , Espécies Reativas de Oxigênio , Diabetes Mellitus Experimental/tratamento farmacológico , Sistemas de Liberação de Medicamentos
13.
Int J Biol Macromol ; 222(Pt A): 1287-1303, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36191788

RESUMO

Oral cancer is one of the most prevalent malignancies worldwide. Here, to prepare a biocompatible tumor-targeted nanoformulation capable of efficient loading of the hydrophobic drug, DTX, human serum albumin was conjugated to poly(lactide) at different HSA: PLA ratios (1:1, 2, 3). The HSA-(PLA)1-3 conjugates were physicochemically characterized by UV, IR, NMR, GPC, pyrene incorporation, and surface tension analysis. Next, the DTX-loaded DTX@HSA-(PLA)1-3 NPs were prepared by the desolvation-self-assembly technique, which was further optimized by DOE. The NPs were characterized by DLS, SEM, DSC, XRD, CD spectroscopy, SDS-PAGE, drug entrapment and loading efficiencies, kinetic stability, drug release, and hemolysis assays. Murine and human oral cancer cell lines, MOC2 and FaDu, were used in monolayers/multicellular spheroids to assess cellular uptake, the extent of cell viability, and apoptosis induction following NPs treatment. The DTX@HSA-(PLA)1-3 NPs were ~ 149-212 nm size range, drug entrapment, ~75-96 %, and loading efficiency, ~21-27 %. The selected DTX@HSA-(PLA)2 NPs showed time-dependent improved targetability towards cancer cells than HSA NPs, indicating the benefit of HSA polymerization in NPs internalization. A time-dependent decrease in cell viability was observed for both the cell lines with IC50 values, 7.12 ± 1.84 and 6.38 ± 1.63 µg/mL, for FaDu and MOC2 cell lines, respectively (48 h post-treatment). The DTX@ HSA-(PLA)2 NPs treatment induced higher apoptotic marker expressions, cell-cycle arrest in the G2/M-phase, DNA damage, and mitochondrial depolarization than free DTX and DTX@HSA NPs. Further, DTX@HSA-(PLA)2 NPs (iv) showed significantly reduced plasma clearance (p < 0.05) and volume of distribution (Vd) than DTX and DTX@HSA NPs. Therefore, the developed polyprotein NPs offer superior therapeutic effect due to their stable drug incorporation, improved cell internalization, and long circulation, revealing their potential as an effective nanomedicine for oral cancer treatment.


Assuntos
Antineoplásicos , Neoplasias Bucais , Nanopartículas , Humanos , Camundongos , Animais , Docetaxel , Albumina Sérica Humana , Taxoides/química , Nanopartículas/química , Poliésteres , Neoplasias Bucais/tratamento farmacológico , Antineoplásicos/química , Portadores de Fármacos/química , Linhagem Celular Tumoral
14.
ACS Appl Mater Interfaces ; 14(43): 49014-49025, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36278376

RESUMO

In recent years, extensive research has been directed toward the successful preparation of nanoscale luminescent thermometers with high sensitivities operative in a broad temperature range. To achieve this goal, we have devised a unique design and facile multistep synthesis of Zr-ctpy-NMOF@TbxEuy compounds by confining Ln-complexes (Ln = Eu3+/Tb3+) into a robust nanoscale Zr-NMOF (MOF-808) via postsynthetic modification. Covalent grafting of 4-(4'-carboxyphenyl)-2,2':6,2″terpyridine ligand (ctpy) with a high triplet state energy and corresponding immobilization of bimetallic Ln3+ ions resulted in yellow light-emitting Zr-ctpy-NMOF@Tb1.66Eu0.14 to achieve a sensitivity of 5.2% K-1 (thermal uncertainty dT < 1 K) operative over a broad temperature range of 25-400 K. To defeat the odds related to the detection of minute temperature changes using luminescent materials, we prepared a white light-emitting Zr-ctpy-NMOF@Tb1.4Eu0.31 that showed temperature-modulated multispectrum chromism where the color drastically changes from green (at 25 K, Q.Y.: 20.21%) to yellowish-green (at 200 K, Q.Y.: 23.13%) to white (at 300 K, Q.Y.: 26.4%) to orange (at 350 K, Q.Y.: 26.93%) and finally red (at 400 K, Q.Y.: 28.2%) with a high energy transfer efficiency of 49.8%, which is further supported by electron-phonon coupling.

15.
ACS Appl Mater Interfaces ; 14(22): 25220-25231, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35613366

RESUMO

Insights into developing innovative routes for the stabilization of photogenerated charge-separated states by suppressing charge recombination in photocatalysts is a topic of immense importance. Herein, we report the synthesis of a metal-organic framework (MOF)-based composite where CdS nanoparticles (NPs) are confined inside the nanosized pores of Zr4+-based MOF-808, namely, CdS@MOF-808. Anchoring l-cysteine into the nanospace of MOF-808 via postsynthetic ligand exchange allows the capture of Cd2+ ions from their aqueous solution, which are further utilized for in situ growth of CdS NPs inside the nanosized MOF pores. The formation of CdS@MOF-808 opens up a possibility for visible-light photocatalysis as CdS NPs (1-2 nm) are a well-studied semiconductor system with a band gap of ∼2.6 eV. The confinement of the CdS NPs inside the MOF pores, close to the Zr4+ cluster, opens up a shorter electron transfer route from CdS to the catalytic Zr4+ cluster and shows a high rate of H2 evolution (10.41 mmol g-1 h-1) from water with a loading of 3.56 wt % CdS. In contrast, a similar composite in which CdS NPs are stabilized on the external surface of MOF-808 reveals poor activity (0.15 mmol g-1 h-1). CdS NPs stabilized on the MOF-808 surface show slower and inefficient electron transfer kinetics compared to CdS stabilized inside the nanospace of the MOF, as realized by the transient absorption measurements. Therefore, this work unveils the critical role of stabilizing the photosensitizer NPs in close proximity of the catalytic sites in MOF systems towards developing highly efficient H2 evolution photocatalysts.

16.
Dalton Trans ; 50(37): 13002-13011, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581361

RESUMO

Five isostructural 1D porous coordination polymers (PCPs) with a general formula of {[M(L)(DMF)(H2O)]·1.5H2O}n [M = TbIII (1), EuIII (2), YbIII (3), NdIII (4) and ErIII (5)] have been synthesized using a flexible tripodal organic linker (L) and characterized. TbIII (1) and EuIII (2) PCPs exhibit metal-based green and red emission, respectively, whereas YbIII (3), NdIII (4) and ErIII (5) PCPs show near-infrared (NIR) emission. Doping EuIII in 1 in a precisely controlled stoichiometric amount leads to different mixed lanthanide PCPs, {[Tb1-xEux(L)(DMF)(H2O)]·1.5H2O}n (1a-1f) that show tunable emission including that of bright white light. The PCPs decorated with Lewis basic -O- binding sites make them potential candidates for the binding and selective sensing of traces of CuII ions, and this is illustrated for PCP 2 (limit of detection = 0.69 ± 0.02 ppm). The photoluminescence of 2 can be recovered by the introduction of a chelating ligand ethylenediaminetetraacetic acid (EDTA) without any structural disintegration, indicating the potential of the lanthanide PCPs for future sensing applications.

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