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1.
Langmuir ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38961769

RESUMO

A comparative approach is employed for the novel synthesis of a magnetically recoverable ternary nanocomposite consisting of g-C3N4-supported Fe3O4 decorated with coinage metals (Au, Ag, and Cu). This synthesis is achieved through a straightforward and convenient one-step grinding protocol. In situ, the nanoparticles were grown on the g-C3N4-assist Fe3O4 matrix (GCFM), and the agglomeration of these nanoparticles on the matrix creates a pathway for the formation of the nanocomposite (NC). The as-formed CNC was confirmed with the help of characterization analyses, namely XRD, FT-IR, HR-TEM, FE-SEM, XPS, VSM, UV-vis, and NMR studies. Together with NPs and GCFM, with the quantum consequence, the activity of the NC shows better electron transfer via transfer of electrons, which grabs tremendous attention toward it, resulting in enhanced plausible photocatalytic degradation toward pharmaceutical compounds, dyes, and anthropogenic pollutants. The activity of the C-NC hikes at 88% for ciprofloxacin (CX) and 90% for paracetamol (PM); furthermore, the activity of the C-NC hikes at 88% and 87% for xylene Cyanol FF (XCF) and malachite green (MLG), respectively. Interestingly, an added advantage is the formation of a C-C bond (homocoupling reaction) in phenylboronic acid (PA) via a greener solvent under ambient conditions. The yield percentage of the conversion product shows satisfactory results, and its reproducibility was good for the prepared ternary NC. The conversion treatment of anthropogenic pollutants, namely 4-nitrophenol, grasps a high percentage (98%). In addition, the NC shows good activity toward both types of bacteria. The reproducibility of the composite also shows virtuous activity against pharmaceutical as well as toxic contaminants. The as-prepared CNC was specifically engineered to perform both bond formation and bond cleavage of organic molecules under ambient conditions for multiple cycles.

2.
EMBO Rep ; 20(7): e47352, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31267705

RESUMO

Melanoma antigen genes (MAGEs) are emerging as important oncogenic drivers that are normally restricted to expression in male germ cells but are aberrantly expressed in cancers and promote tumorigenesis. Mechanistically, MAGEs function as substrate specifying subunits of E3 ubiquitin ligases. Thus, the activation of germline-specific genes in cancer can drive metabolic and signaling pathways through altered ubiquitination to promote tumorigenesis. However, the mechanisms regulating MAGE expression and activity are unclear. Here, we describe how the MAGE-A3/6 proteins that function as repressors of autophagy are downregulated in response to nutrient deprivation. Short-term cellular starvation promotes rapid MAGE-A3/6 degradation in a proteasome-dependent manner. Proteomic analysis reveals that degradation of MAGE-A3/6 is controlled by the CRL4-DCAF12 E3 ubiquitin ligase. Importantly, the degradation of MAGE-A3/6 by CRL4-DCAF12 is required for starvation-induced autophagy. These findings suggest that oncogenic MAGEs can be dynamically controlled in response to stress to allow cellular adaptation, autophagy regulation, and tumor growth and that CRL4-DCAF12 activity is responsive to nutrient status.


Assuntos
Antígenos de Neoplasias/metabolismo , Proteínas de Neoplasias/metabolismo , Nutrientes/deficiência , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Autofagia , Regulação para Baixo , Células HEK293 , Células HeLa , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios Proteicos
3.
Nanoscale ; 16(25): 12081-12094, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38818925

RESUMO

An innovative means of synthesizing mechanically recoverable ternary nanocomposite (NC) comprising Fe3O4 supported on Oryza sativa husk (OSH) and ornamented with 3d tetra-metals (M = Mn, Co, Ni, Cu) is proposed using a manual grinding method. This NC was prepared via a one-step manual method. The added advantage of this method is the non-usage of solvents during the synthesis of the NC. In situ, the NPs were grown on OSH-supported magnetite NPs, where they combined to form a matrix to facilitate the formation of the metal NPs in it. The as-crafted Oryza sativa husk-supported magnetite @ tetra-metallic nanocore hybrid (OSFTC) was confirmed via several characterisation techniques, such as XRD, FT-IR, HR-TEM, FE-SEM, XPS, VSM, NMR, and UV-vis analysis. The interesting twist in this NC is that the leaching-in of metals toward the core of the NC increases the magnetic nature of the composite as evidenced by VSM analysis. The electrostatic attraction between NPs formed and the matrix plausibly results in enhanced photocatalytic degradation of pharma-waste in an efficient way. The activity of the OSFTC increases for ciprofloxacin and paracetamol by 67 and 71%. Furthermore, the hydrogenation of anthropogenic pollutants via a foreign agent yields a good conversion percentage of 92%. In addition, the noxious hexavalent chromium is converted to a trivalent cation with the help of OSFTC, indicating good conversion under ambient conditions. Herein, OSFTC also exhibited effective activity against both Gram-positive and Gram-negative bacteria. Moreover, the ternary composite demonstrates consistent and commendable activity against pharmaceutical compounds and carcinogenic pollutants. The OSFTC was designed in a way to perform the cleavage of bonds for toxic materials efficiently.

4.
Waste Manag ; 163: 61-72, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37001313

RESUMO

In modern era, electronic wastes are one of the major threats around us, most of them are reused with less efficiency instead of re-usage, and conversion into valuable products is highly recommended. In this work, we report an innovative approach for the synthesis of highly photoluminescent CDs from waste dry-cell batteries through one-step hydrothermal treatment for the detection and degradation of environmental pollutants. The as-prepared CDs were studied by X-ray photoelectron spectroscopy (XPS), HR-TEM studies, X-ray diffractometer (XRD), Raman spectrometer, FTIR spectroscopy, UV-visible spectrophotometer, and spectrofluorometric measurements. The calculated quantum yield for synthesized CDs was around 13 %. The CDs have uniform particle size distribution, strong photoluminescent behavior, and possess high stability against various environmental conditions. Also, CDs display the selective and sensitive detection of Cr6+ and Co2+ and ions with a detection limit of around 0.11 µM and 0.10 µM respectively. The possible mechanism of CDs was also examined. Moreover, the photocatalytic activity of CDs with Bromothymol Blue (BTB) dye was studied. The degradation efficiency of BTB dye can be achieved at around 84 % over 180 min under the irradiation of direct sunlight in presence of H2O2. To date, it's the first time we have recycled waste dry-cell batteries into CDs as an effective probe for the detection and decomposition of environmental pollution. Furthermore, this work provides not only an easier route to make good quality and improved photoluminescent CDs from waste material like used batteries and also paves way for the reconversion of global treating waste. Finally, the outstanding detection capability with multiple properties of as-prepared CDs provides various environmental applications like the detection of pollutants and carcinogenic polluted water treatment.


Assuntos
Azul de Bromotimol , Carbono , Carbono/química , Peróxido de Hidrogênio , Metais , Íons/química
5.
Indian J Ophthalmol ; 67(4): 541-544, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30900590

RESUMO

Digital fundus imaging is being used in diagnosis, documentation, and sharing of many retinal diseases and hence forms an essential part of ophthalmology. The use of smartphones for the same has been ever increasing. There is a need for simpler devices to couple the 20D lens and smartphone so as to take fundus photographs which can help in fundus documentation. This article describes a simple inexpensive technique of preparing a smartphone fundus photography device (Trash To Treasure (T3) Retcam) from the used materials in the clinics within minutes. This article will also review the optical principles of the T3 Retcam and describe the step-by-step method to record good-quality retinal image/videos. This inexpensive device is made by recycling and modifying the plastic hand sanitizer bottle in the clinics/hospitals which can be used for documenting, diagnosing, screening, and academic purposes.


Assuntos
Técnicas de Diagnóstico Oftalmológico/instrumentação , Oftalmoscopia/métodos , Fotografação/instrumentação , Retina/diagnóstico por imagem , Doenças Retinianas/diagnóstico , Telemedicina/métodos , Gravação em Vídeo/instrumentação , Desenho de Equipamento , Fundo de Olho , Humanos , Smartphone
6.
Cell Death Differ ; 26(5): 902-917, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30042493

RESUMO

BCL2A1 is an anti-apoptotic member of the BCL-2 family that contributes to chemoresistance in a subset of tumors. BCL2A1 has a short half-life due to its constitutive processing by the ubiquitin-proteasome system. This constitutes a major tumor-suppressor mechanism regulating BCL2A1 function. However, the enzymes involved in the regulation of BCL2A1 protein stability are currently unknown. Here, we provide the first insight into the regulation of BCL2A1 ubiquitination. We present evidence that TRIM28 is an E3 ubiquitin-ligase for BCL2A1. Indeed, endogenous TRIM28 and BCL2A1 bind to each other at the mitochondria and TRIM28 knock-down decreases BCL2A1 ubiquitination. We also show that TRIM17 stabilizes BCL2A1 by blocking TRIM28 from binding and ubiquitinating BCL2A1, and that GSK3 is involved in the phosphorylation-mediated inhibition of BCL2A1 degradation. BCL2A1 and its close relative MCL1 are thus regulated by common factors but with opposite outcome. Finally, overexpression of TRIM28 or knock-out of TRIM17 reduced BCLA1 protein levels and restored sensitivity of melanoma cells to BRAF-targeted therapy. Therefore, our data describe a molecular rheostat in which two proteins of the TRIM family antagonistically regulate BCL2A1 stability and modulate cell death.


Assuntos
Apoptose/genética , Antígenos de Histocompatibilidade Menor/genética , Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas com Motivo Tripartido/genética , Proteína 28 com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Morte Celular/genética , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosforilação/genética , Complexo de Endopeptidases do Proteassoma/genética , Ligação Proteica/genética , Estabilidade Proteica , Proteólise/efeitos dos fármacos , Ubiquitinação/genética
7.
Sci Adv ; 5(5): eaav4832, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31149633

RESUMO

Ensuring robust gamete production even in the face of environmental stress is of utmost importance for species survival, especially in mammals that have low reproductive rates. Here, we describe a family of genes called melanoma antigens (MAGEs) that evolved in eutherian mammals and are normally restricted to expression in the testis (http://MAGE.stjude.org) but are often aberrantly activated in cancer. Depletion of Mage-a genes disrupts spermatogonial stem cell maintenance and impairs repopulation efficiency in vivo. Exposure of Mage-a knockout mice to genotoxic stress or long-term starvation that mimics famine in nature causes defects in spermatogenesis, decreased testis weights, diminished sperm production, and reduced fertility. Last, human MAGE-As are activated in many cancers where they promote fuel switching and growth of cells. These results suggest that mammalian-specific MAGE genes have evolved to protect the male germline against environmental stress, ensure reproductive success under non-optimal conditions, and are hijacked by cancer cells.


Assuntos
Antígenos Específicos de Melanoma/genética , Neoplasias/genética , Espermatogênese/genética , Estresse Fisiológico/genética , Testículo/fisiologia , Animais , Dano ao DNA , Desoxiglucose/farmacologia , Evolução Molecular , Feminino , Regulação Neoplásica da Expressão Gênica , Células Germinativas , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espermatogônias/efeitos dos fármacos , Inanição
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