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1.
Chem Asian J ; : e202400138, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733617

RESUMEN

The aminotroponiminate (ATI) ligand stabilized germylene cation [(i-Bu)2ATIGe][B(C6F5)4] (2) is found to be an efficient low-valent main-group catalyst for the cyanosilylation of aldehydes and ketones (ATI = aminotroponiminate). It was synthesized by reacting [(i-Bu)2ATIGeCl] (1) with Na[B(C6F5)4]. The catalytic cyanosilylation of diverse aliphatic and aromatic carbonyl compounds (aldehydes and ketones) using 0.075-0.75 mol% of compound 2 was completed within 5-45 min. The catalytic efficiency seen with aliphatic aldehydes was around 15,800 h-1, making compound 2 a capable low-valent main-group catalyst for the aldehyde and ketone cyanosilylation reactions.

2.
Chem Sci ; 15(17): 6465-6477, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38699254

RESUMEN

At the cutting edge of high-performance single-molecule magnets (SMMs) lie lanthanide-based complexes, renowned for their potent magnetic anisotropy. SMMs containing one metal centre are defined as single-ion magnets (SIMs). The performance of SMMs is measured generally via the barrier height for magnetisation reversal (Ueff) and blocking temperature (TB), below which the magnetisation is fully frozen. To enhance the Ueff and TB values in lanthanide-based SMMs, the static crystal field splitting of mJ levels has been effectively adjusted through ligand design, leveraging the oblate/prolate ground state 4f electron density shape. However, the maximum fine-tuning achievable through ligand design, known as the axial limit, has already been reached in this class of compounds. This necessitates new design principles to enhance SMM characteristics to better suit end-user applications. Among other avenues that can be explored to improve SMM characteristics, a deeper understanding of spin-phonon coupling is critical to advancing TB values. However, there are only a handful of examples where this has been deciphered. In this work, using a combination of DFT and ab initio CASSCF calculations, we have performed spin-phonon calculations on five classes of pentagonal bipyramidal Dy(iii) SIMs exhibiting TB values in the range of 4.5 K to 36 K ([Dy(bbpen)Br] (1, H2bbpen = N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-methylpyridyl)ethylenediamine), [Dy(OCMe3)Br(THF)5][BPh4] (2) [Dy(OSiMe3)Br(THF)5] [BPh4] (3), [Dy(LN5)(Ph3SiO)2](BPh4)·CH2Cl2 (4) and [L2Dy(H2O)5][I]3·L2·H2O (5, L = tBuPO(NHiPr)2)). Unlike the method employed elsewhere for the calculation of spin-phonon coupling, in this work, we have employed a set of criteria and intuitively selected vibrational modes to perform the spin-phonon coupling analysis. The approach provided here not only reduces the computational cost significantly but also suggests chemical intuition to improve the performance of this class of compounds. Our calculations reveal that low-energy vibrational modes govern the magnetisation relaxation in these SIMs. A flexible first coordination sphere found on some of the complexes was found to be responsible for low-energy vibrations that flip the magnetisation, reducing the TB values drastically (complexes 2 and 3). On the other hand, a rigid first coordination sphere and a stiff ligand framework move the spin-vibrational coupling that causes the relaxation to lie beyond the secondary coordination sphere, resulting in an increase in TB values. Our calculations also reveal that not only the atoms in the first coordination sphere but also those in the secondary coordination sphere affect the performance of the SMMs. Learning from this exercise, we have undertaken several in silico models based on these vibrations to improve the TB values. Some of these predictions were correlated with literature precedents, offering confidence in the methodology employed. To this end, our comprehensive investigation, involving twenty-three molecules/models and five sets of geometries for pentagonal bipyramidal Dy(iii) single-ion magnets (SIMs), unveils a treasure trove of chemically sound design clues, poised to enhance the TB values in this fascinating molecular realm.

3.
Inorg Chem ; 62(46): 18915-18925, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37947449

RESUMEN

Three mononuclear cobalt(II) tetrahedral complexes [Co(CzPh2PO)2X2] (CzPh2PO = (9H-carbazol-9-yl)diphenylphosphine oxide and X = Cl (1), Br (2), I (3)) have been synthesized using a simple synthetic approach to examine their single-ion magnetic (SIM) behavior. A detailed study of the variation in the dynamic magnetic properties of the Co(II) ion in a tetrahedral ligand field has been carried out by the change of the halide ligand. The axial zero-field splitting parameter D was found to vary from -16.4 cm-1 in 1 to -13.8 cm-1 in 2 and +14.6 cm-1 in 3. All the new complexes exhibit field-induced SIM behavior. The results obtained from ab initio CASSF calculations match well with the experimental data, revealing how halide ions induce a change in the D value as we move from Cl- to I-. The ab initio calculations further reveal that the change in the sign of D is due to the multideterminant characteristics of the ground state wave function of 1 and 2, while single-determinant characteristics are instead observed for 3. To gain a better understanding of the relationship between the structural distortion and the sign and magnitude of D values, magnetostructural D correlations were developed using angular relationships, revealing the importance of structural distortions over the heavy halide effect in controlling the sign of D values. This study broadens the scope of employing electronically and sterically modified phosphine oxide ligands in building new types of air-stable Co(II) SIMs.

4.
Cancers (Basel) ; 15(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37509331

RESUMEN

SELENOF expression is significantly lower in aggressive breast tumors compared to normal tissue, indicating that its reduction or loss may drive breast tumorigenesis. Deletion of SELENOF in non-tumorigenic immortalized breast epithelial MCF-10A cells resulted in enhanced proliferation, both in adherent culture and matrix-assisted three-dimmensional (3D) growth. Modulation of SELENOF in vitro through deletion or overexpression corresponded to changes in the cell-cycle regulators p21 and p27, which is consistent with breast tumor expression data from the METABRIC patient database. Together, these findings indicate that SELENOF affects both proliferation and cell death in normal epithelial and breast cancer cells, largely through the regulation of p21 and p27. In glandular cancers like breast cancer, the filling of luminal space is one of the hallmarks of early tumorigenesis. Loss of SELENOF abrogated apoptosis and autophagy, which are required for the formation of hollow acini in MCF-10A cells in matrix-assisted 3D growth, resulting in luminal filling. Conversely, overexpression of SELENOF induced cell death via apoptosis and autophagy. In conclusion, these findings are consistent with the notion that SELENOF is a breast tumor suppressor, and its loss contributes to breast cancer etiology.

5.
Breast Cancer Res Treat ; 201(3): 561-570, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37477798

RESUMEN

PURPOSE: The oncogenic factor ZNF217 promotes aggressive estrogen receptor (ER)+breast cancer disease suggesting that its inhibition may be useful in the clinic. Unfortunately, no direct pharmacological inhibitor is available. Dimethyl fumarate (DMF) exhibits anti-breast cancer activities, in vitro and in pre-clinical in vivo models. Its therapeutic benefits stem from covalent modification of cellular thiols such as protein cysteines, but the full profile of molecular targets mediating its anti-breast cancer effects remains to be determined. METHODS: ER+breast cancer cells were treated with DMF followed by cysteine-directed proteomics. Cells with modulated ZNF217 levels were used to probe the efficacy of DMF. RESULTS: Covalent modification of ZNF217 by DMF identified by proteomics was confirmed by using a DMF-chemical probe. Inhibition of ZNF217's transcriptional activity by DMF was evident on reported ZNF217-target genes. ZNF217 as an oncogene has been shown to enhance stem-like properties, survival, proliferation, and invasion. Consistent with ZNF217 inhibition, DMF was more effective at blocking these ZNF217-driven phenotypes in cells with elevated ZNF217 expression. Furthermore, partial knockdown of ZNF217 led to a reduction in DMF's efficacy. DMF's in vivo activity was evaluated in a xenograft model of MCF-7 HER2 cells that have elevated expression of ZNF217 and DMF treatment resulted in significant inhibition of tumor growth. CONCLUSION: These data indicate that DMF's anti-breast cancer activities in the ER+HER2+models, at least in part, are due to inhibition of ZNF217. DMF is identified as a new covalent inhibitor of ZNF217.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Dimetilfumarato/farmacología , Dimetilfumarato/uso terapéutico , Receptores de Estrógenos , Transactivadores/genética , Transactivadores/metabolismo , Transactivadores/uso terapéutico , Células MCF-7
6.
Chem Commun (Camb) ; 59(22): 3206-3228, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36789911

RESUMEN

Enhancing blocking temperature (TB) is one of the holy grails in Single Molecule Magnets(SMMs), as any future potential application in this class of molecules is directly correlated to this parameter. Among many factors contributing to a reduction of TB value, Quantum Tunnelling of Magnetisation (QTM), a phenomenon that is a curse or a blessing based on the application sought after, tops the list. Theoretical tools based on density functional and ab initio CASSCF/RASSI-SO methods have played a prominent role in estimating various spin Hamiltonian parameters and establishing the mechanism of magnetization relaxation in this class of molecules. Particularly, various strategies to quench QTM effects go hand-in-hand with experiments, and different methods proposed to quell QTM effects are scattered in the literature. In this perspective, we have explored various approaches that are proposed in the literature to quench QTM effects, and these include the role of (i) local symmetry of lanthanides, (ii) super-exchange interaction in {3d-4f} complexes, (iii) direct-exchange interaction in {radical-4f} and metal-metal bonded complexes to suppress the QTM, (iv) utilizing external stimuli such as an electric field or pressure to modulate the QTM and (v) avoiding QTM effects by stabilising toroidal states in 4f and {3d-4f} clusters. We believe the strategies summarized here will help to design new-generation SMMs.

7.
J Cell Physiol ; 237(8): 3127-3163, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35644005

RESUMEN

Over 20 different growth factors belonging to the bone morphogenetic proteins (BMPs) family have been identified, that were initially discovered as growth factors that promote osteogenesis, and play a vital role in bone remodeling and various developmental processes. Numerous studies have explored the aberrance level of BMPs in various cancer types, questioning their role in tumorigenesis. These growth factors have been studied extensively over the decades to define their function during cancer progression and metastasis. Nonetheless, the BMP expression profiles in clinical samples correlate with cancer prognosis. Based on clinical data, various in vitro, and in vivo findings, it has been reported that BMPs have dual roles, that is, they can act as a tumor suppressor, tumor promoter, and both. On contrary, some studies have reported that BMPs have an oncogenic role while others reported their tumor-suppressive role. So, this creates a knowledge gap in the behavior of different types of BMPs. Thus, this review updates and bridges the knowledge gap while considering the dual behavior of various BMPs including BMP-2, 4, 6, 7, 9, and 10. Moreover, the comprehensive analysis provides insight into the role of different BMPs in cancer potential and how the behavior of BMPs alters in the tissue-dependent context in various cancers by modulating canonical SMAD signaling, various noncanonical pathways such as PI3K/AKT, NF-κB, MAPK, STAT, cMYC, cJUN, and so forth. This review also enlightens the role of BMP heterodimers, several ligand-binding proteins (agonists and antagonists), mutational status of BMP receptors, and the tumor microenvironment in relating to the bi-functional aspects of the BMPs in various cancerous tissues by regulating the levels of BMP's canonical and noncanonical signals.


Asunto(s)
Proteínas Morfogenéticas Óseas , Neoplasias , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Genes Supresores de Tumor , Humanos , FN-kappa B/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Oncogenes , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Microambiente Tumoral
8.
Inorg Chem ; 61(26): 9906-9917, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35727882

RESUMEN

The recently reported compound [DyIIILF](CF3SO3)2·H2O (L = 1,4,7,10-tetrakis(2-pyridylmethyl)-1,4,7,10-tetraaza-cyclododecane) displays a strong axial magnetic anisotropy, due to the short axial Dy-F bond, and single-molecule magnet (SMM) behavior. Following our earlier [DyIIILF]2+ work, herein we report the systematic structural and magnetic study of a family of [LnIIILF](CF3SO3)2·H2O compounds (Ln(III) = 1-Ce, 2-Pr, 3-Nd, 4-Eu, 5-Tb, 6-Ho, 7-Er, 8-Tm, and 9-Yb). From this series, the Ce(III) and Nd(III) analogues show slow relaxation of the magnetization under an applied direct current magnetic field, which is modeled using a Raman process. Complete active space self-consistent field theoretical calculations are employed to understand the relaxation pathways in 1-Ce and 3-Nd and also reveal a large tunnel splitting for 5-Tb. Additional computational studies on model compounds where we remove the axial F- ligand, or replace F- with I-, highlight the importance of the F- ligand in creating a strong axial crystal field for 1-Ce and 3-Nd and for promoting the SMM behavior. Importantly, this systematic study provides insight into the magnetic properties of these lighter lanthanide ions.

10.
Environ Sci Pollut Res Int ; 29(36): 54916-54938, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35314937

RESUMEN

Monitoring of groundwater is essential in the alluvial region of Tarn-Taran district, western Punjab, India where this freshwater source is being overexploited causing quality deterioration, groundwater depletion and posing serious threats to inhabitants. The present integrated study was conducted to appraise quality and suitability of groundwater for drinking/irrigation purposes, hydro-geochemical characteristics, source identification and associated health risks. In this study, 96% and 51% samples were detected with arsenic (As) and uranium (U), respectively higher than their acceptable limits posing high cancerous risks to local inhabitants via ingestion. Further, the quality indices revealed that groundwater of the study region is appropriate for irrigation but not suitable for drinking purposes. Hydro-geochemical studies showed that 83% of samples belonged to Ca2+-Mg2+-HCO3- type with major contribution of natural geogenic processes like rock-water interactions, silicate and carbonate dissolution along with reverse ion-exchange mechanisms in aquifer chemistry. Multivariate statistics revealed that along with geogenic sources, contribution of anthropogenic activities such as injudicious application of agrochemicals and domestic waste discharge was also very significant. Hazard quotient values for As were found to be 2.119 and 2.743 for children and adults, respectively representing both population groups prone to non-cancerous health risks due to As intake. Children were found to be more vulnerable than adults. This study draws an attention of public and local government about the current status of groundwater pollution in Tarn-Taran district, so that proper remediation steps can be taken to ensure the availability of good quality water.


Asunto(s)
Arsénico , Agua Subterránea , Contaminantes Químicos del Agua , Adulto , Arsénico/análisis , Niño , Monitoreo del Ambiente , Humanos , India , Medición de Riesgo , Agua , Contaminantes Químicos del Agua/análisis , Calidad del Agua
11.
Inorg Chem ; 61(14): 5572-5587, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35348317

RESUMEN

The mechanistic investigations between Cu(II) and the anisotropic lanthanides (Ln(III)) are not much explored to date. This is due to the complicated energy spectrum which arises due to the orbital angular momentum of anisotropic lanthanides. Interestingly, the exchange coupling J in Ln(III)-Cu(II) systems was found to be antiferromagnetic for <4f7 metal ions and ferromagnetic for ≥4f7 metal ions, while the net magnitude of JTotal strength gradually decreases moving from f1 to f13. While this is established in several examples, the reason for this intriguing trend is not rationalized. In this article, we have taken up these challenging tasks by synthesizing a family of complexes with the general molecular formula [Cu2Ln(HL)4(NO3)](NO3)2, where Ln = La (1-La), Ce (2-Ce), Pr (3-Pr), Gd (4-Gd), Tb (5-Tb), Dy (6-Dy), and Ho (7-Ho) and HL = C15H15N1O3; (2-methoxy-6-[(E)-2'-hydroxymethyl-phenyliminomethyl]-phenolate) is a monodeprotonated tridentate Schiff base ligand. Detailed dc magnetic susceptibility measurements performed for all the complexes reveal that the Cu(II) ion is coupled ferromagnetically to the respective Ln(III) ion, which has more than seven electrons in the 4f shell, while an antiferromagnetic coupling is witnessed if Ln(III) has less than seven electrons. The strength of the exchange coupling constant was quantitatively determined for representative complexes from the high-field/high-frequency electron paramagnetic resonance spectroscopy which follows the order of 4-Gd (1.50(10) cm-1) > 5-Tb (1.18(10) cm-1) > 6-Dy (0.56(10) cm-1 based on the -2JCu-Ln(SCu1→·JLnz→+SCu2→·JLnz→) spin Hamiltonian. The increased axiality in 5-Tb and 6-Dy due to the presence of 3d ions in the near vicinity of an oblate ion and the increased exchange coupling strength between Cu(II) and Tb(III) or Dy(III) is the ideal combination to stabilize magnetic bistability in these complexes in the absence of an external magnetic field with the effective energy barrier of 15.7 K (τo = 2.49 × 10-6 s) and 12.6 K (τo = 1.70 × 10-5 s), respectively. To rationalize this experimental trend, we have performed ab initio CASSCF and DFT calculations. To compute the J values, we have employed POLY_ANISO routines and utilized the computed data to establish the generic mechanism of magnetic coupling in {Cu-Ln-Cu} motifs. These mechanistic findings reveal the importance of 5d orbitals and their energy with respect to the dx2-y2 orbital of Cu(II) ions in controlling the magnetic coupling of {Cu-4f} complexes.

12.
Inorg Chem ; 61(4): 2141-2153, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35049278

RESUMEN

The present work is part of our ongoing quest for developing functional inorganic complexes using unorthodox pyridyl-pyrazolyl-based ligands. Accordingly, we report herein the synthesis, characterization, and luminescence and magnetic properties of four 3d-4f mixed-metal complexes with a general core of Ln2Zn6 (Ln = Dy, Gd, Tb, and Eu). In stark contrast to the popular wisdom of using a compartmental ligand with separate islands of hard and soft coordinating sites for selective coordination, we have vindicated our approach of using a ligand with overcrowded N-coordinating sites that show equal efficiency with both 4f and 3d metals toward multinuclear cage-cluster formation. The encouraging red and green photolumiscent features of noncytotoxic Eu2Zn6 and Tb2Zn6 complexes along with their existence in nanoscale dimension have been exploited with live-cell confocal microscopy imaging of human breast adenocarcinoma (MCF7) cells. The magnetic features of the Dy2Zn6 complex confirm the single-molecule-magnet behavior with befitting frequency- and temperature-dependent out-of-phase signals along with an Ueff value of ∼5 K and a relaxation time of 8.52 × 10-6 s. The Gd2Zn6 complex, on the other hand, shows cryogenic magnetic refrigeration with an entropy change of 11.25 J kg-1 K-1 at a magnetic field of 7 T and at 2 K. Another important aspect of this work reflects the excellent agreement between the experimental results and theoretical calculations. The theoretical studies carried out using the broken-symmetry density functional theory, ORCA suite of programs, and MOLCAS calculations using the complete-active-space self-consistent-field method show an excellent synergism with the experimentally measured magnetic and spectroscopic data.

13.
Environ Sci Pollut Res Int ; 29(5): 7225-7239, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34472029

RESUMEN

Groundwater samples from Kapurthala (45), Jalandhar (70), and Hoshiarpur (70) districts from northern Punjab, India, were studied for seasonal variation (pre-monsoon and post-monsoon) of uranium distribution and physicochemical parameters, quality and suitability for drinking purposes, source apportionment, and health risks. The average uranium concentration (in µg L-1) in Kapurthala, Jalandhar, and Hoshiarpur districts was 12.7, 18.8, and 7.0, respectively, in pre-monsoon and 8.0, 17.3, and 5.6, respectively, in post-monsoon. In both seasons, uranium concentration was below WHO limit (30 µg L-1) in more than 90% of groundwater samples, and it was found to exhibit positive correlation majorly with TDS, EC, and total alkalinity. Principal component analysis revealed dissolution of rocks/minerals contributing to mineralization of associated aquifers in addition to some anthropogenic activities such as excessive application of fertilizers/pesticides and dumping of domestic waste followed by their seepage into the groundwater table. All groundwater samples fall in very good to good drinking groundwater quality and its quality is more improved in post-monsoon season owing to dilution of various inorganic salts during groundwater recharge in monsoon season. Average Hazard Index (HI) values due to ingestion of U, F-, and NO3- via drinking water for both adults and children were found to be marginally greater than safe limit of 1 with major contribution from F-. It is advisable to local government/public that regular monitoring of groundwater and proper management policies or strategies should be adopted followed by their implementation to control groundwater pollution in three districts.


Asunto(s)
Agua Subterránea , Uranio , Contaminantes Químicos del Agua , Efectos Antropogénicos , Monitoreo del Ambiente , India , Uranio/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua
14.
Chem Sci ; 12(34): 11506-11514, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34667554

RESUMEN

Lanthanide based single molecular magnets (SMMs), particularly dysprocenium based SIMs, are well known for their high energy barrier for spin reversal (U eff) and blocking temperatures (T B). Enhancing these two parameters and at the same time obtaining ambient stability is key to realising end-user applications such as compact storage or as qubits in quantum computing. In this work, by employing an array of theoretical tools (DFT, ab initio CASSCF and molecular dynamics), we have modelled six complexes [(η5-corannulene)Dy(Cp)] (1), [(η5-corannulene)Dy(C6H6)] (2), [(η6-corannulene)Dy(Cp)] (3), [(η6-corannulene)Dy(C6H6)] (4), [(exo-η5-corannulene)Dy(endo-η5-corannulene)] (5), and [(endo-η5-corannulene)Dy(endo-η5-corannulene)] (6) containing corannulene as a capping ligand to stabilise Dy(iii) half-sandwich complexes. Our calculations predict a strong axiality exerted by the Dy-C interactions in all complexes. Ab initio calculations predict a very large barrier height for all six molecules in the order 1 (919 cm-1) ≈ 3 (913 cm-1) > 2 (847 cm-1) > 4 (608 cm-1) ≈ 5 (603 cm-1) ≈ 6 (599 cm-1), suggesting larger barrier heights for Cp ring systems, followed by six-membered arene systems and then corannulene. DFT based molecular dynamics calculations were performed on complexes 3, 5 and 6. For complexes 3 and 5, the geometries that are dynamically accessible are far fewer. The range of U eff computed for molecular dynamics snapshots is high, indicating a possibility of translating the large U eff obtained into attractive blocking temperatures in these complexes, but the converse is found for 6. Furthermore, an in-depth C-H bond vibrational analysis performed on complex 3 suggests that the vibration responsible for reducing the blocking temperature in dysprocenium SIMs is absent here as the C-H bonds are stronger and corannulene steric strain prevents the C(Cp)-Dy-C(Cor) bending. As [(η6-corannulene)TM(X)]+ (TM = Ru, Zr, Os, Rh, Ir and X = C5Me5, C6Me6) are known, the predictions made here have a higher prospect of yielding stability under ambient conditions, a very large U eff value and a high blocking temperature - a life-giving combination to new generation SMMs.

15.
Environ Monit Assess ; 193(4): 159, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33660097

RESUMEN

Mansa district in Malwa region of South-West Punjab has gained significant attention due to elevation in number of patients suffering from diverse diseases especially cancer and consumption of contaminated groundwater could be one of the possible reasons. The present study reports the assessment of 59 groundwater samples from Mansa district by evaluating physicochemical characteristics, potentially toxic element (PTE) contamination and associated health implications followed by analysis of water quality status using various indices. Multivariate statistics were applied for source identification of PTEs in groundwater. The study revealed occurrence of PTEs with mean (µg L-1) dominance order of As (650.8) > U (104.14) > Zn (55.3) > Fe (34.4) > Hg (8.3) > Mn (5.1) > Cu (4.1) > Cr (2.7) > Pb (2.4). One hundred and 71.19% groundwater samples were found to be seriously contaminated with As and U, respectively, and posing high cancer risks to local residents via ingestion. Higher hazard indices of 16.64 and 12.85 for children and adults, respectively, indicated high non-carcinogenic health risks to both population groups but children were observed to be more vulnerable. Correlation analysis showed positive correlations of U with total dissolved solids (TDS), fluoride (F-) and total alkalinity (TA). Principal component analysis (PCA) and cluster analysis (CA) revealed the contribution of both geogenic (weathering of rocks) and anthropogenic sources (overuse of agrochemicals in agricultural lands and release of inefficiently treated industrial effluents) for deteriorating the groundwater quality of study area. The study counsels the inhabitants to consume treated groundwater as ingestion route was identified as the primary route of exposure.


Asunto(s)
Agua Subterránea , Metales Pesados , Contaminantes Químicos del Agua , Adulto , Niño , Monitoreo del Ambiente , Humanos , India/epidemiología , Metales Pesados/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
16.
Artículo en Inglés | MEDLINE | ID: mdl-32427088

RESUMEN

Autophagy is an evolutionarily conserved pathway that eliminates unwanted proteins out of the cell and increases cell survival. However, dysfunctional autophagy is associated with cancer progression, cellular adaptation, cancer metastasis and makes it an attractive therapeutic target. MicroRNAs (miRNAs) are small single-stranded non-coding RNA molecules that usually bind to 3'UTR of mRNAs. This interaction eventually inhibits protein synthesis by repressing translation and/or by degrading mRNAs. miRNAs play a crucial role in the regulation of autophagy and also behave as both tumor suppressors and promoters in colorectal cancer. This paper defines an overall molecular view of how miRNAs regulate the dual role of autophagy in colorectal cancer. It also highlights how long noncoding RNAs modulate miRNAs expression to regulate autophagy in colorectal cancer. Thus, targeting autophagy by miRNAs seems to be a potential therapeutic strategy for colorectal cancer.


Asunto(s)
Autofagia/genética , Neoplasias Colorrectales/patología , MicroARNs/fisiología , Animales , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/terapia , Regulación Neoplásica de la Expresión Génica , Humanos , Transducción de Señal/genética
17.
J Food Biochem ; 44(8): e13333, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32548903

RESUMEN

Omega-3 fatty acids (ω-3FAs) such as Docosahexaenoic acid (DHA) and Eicosapentanoic acid (EPA), are active ingredient of fish oil, which have larger health benefits against various diseases including cardiovascular, neurodegenerative, cancers and bone diseases. Substantial studies documented a preventive role of omega-3 fatty acids in pathological calcification like vascular calcification and microcalcification in cancer tissues. In parallel, these fatty acids improve bone quality probably by preventing bone decay and augmenting bone mineralization. This study also addresses that the functions of ω-3FAs not only depend on tissue types, but also work through different molecular mechanisms for preventing pathological calcification in various tissues and improving bone health. PRACTICAL APPLICATIONS: Practical applications of the current study are to improve the knowledge about the supplementation of omega-3 fatty acids. This study infers that supplementation of omega-3 fatty acids aids in bone preservation in elder females at the risk of osteoporosis and also, on the contrary, omega-3 fatty acids interfere with pathological calcification of vascular cells and cancer cells. Omega-3 supplementation should be given to the cardiac patients because of its cardio protective role. In line with this, omega-3 supplementation should be included with chemotherapy for cancer patients as it can prevent osteoblastic potential of breast cancer patients, responsible for pathological mineralization, and blocks off target toxicities. Administration of omega-3 fatty acid with chemotherapy will not only improve survival of cancer patients, but also improve the bone quality. Thus, this study allows a better understanding on omega-3 fatty acids in combating pathological complications such as osteoporosis, vascular calcification, and breast microcalcification.


Asunto(s)
Calcinosis , Ácidos Grasos Omega-3 , Anciano , Densidad Ósea , Calcinosis/tratamiento farmacológico , Calcinosis/prevención & control , Ácidos Docosahexaenoicos/farmacología , Ácidos Docosahexaenoicos/uso terapéutico , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-3/uso terapéutico , Femenino , Aceites de Pescado , Humanos
18.
Nutr Cancer ; 72(5): 873-883, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31409173

RESUMEN

Microcalcification seems to be an assurance signature for the prediction of breast cancer malignancy. However, neither systematic study for deciphering the molecular mechanism of mammary microcalcification has yet been conducted, nor a mechanistic study has been performed to find out its prevention. Thus, this study firstly aimed at determining if malignant breast tissues/metastatic breast cancer cells exhibit elevated intrinsic osteoblast-like potential responsible for driving the pathological microcalcification in breast tumors. Here, tumor sample analysis showed higher levels of various osteogenic genes (e.g., Runx2, osterix), and increased ALP activity and calcification in malignant breast tissues when compared to benign tissues, indicating the existence of elevated osteoblast-like potential in malignant breast tissues as compared to benign tissues. Similarly, cell culture study found that metastatic MDA-MB-231 cells acquired a higher osteoblast-like potential as compared to less metastatic breast cancer MCF-7 cells. It was also noticed that osteoinducer bone morphogenetic protein 2 (BMP-2) increased osteoblast-like differentiation and calcification potential in breast cancer cells. Moreover, omega-3 fatty acid docosahexaenoic acid (DHA) showed an inhibitory effect on BMP-2 induced osteoblast-like potential presumably by abrogating BMP signaling. Thus, this study for the first time unraveled that DHA may mitigate microcalcification by blocking osteoblast-like potential of breast cancer cells.


Asunto(s)
Proteína Morfogenética Ósea 2/antagonistas & inhibidores , Neoplasias de la Mama/tratamiento farmacológico , Ácidos Docosahexaenoicos/farmacología , Osteoblastos/efectos de los fármacos , Proteína Morfogenética Ósea 2/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Calcinosis/tratamiento farmacológico , Calcinosis/metabolismo , Calcinosis/patología , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Femenino , Humanos , Osteoblastos/metabolismo , Osteoblastos/patología , Transducción de Señal
19.
Mol Cell ; 75(2): 382-393.e5, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31229404

RESUMEN

The iron-sensing protein FBXL5 is the substrate adaptor for a SKP1-CUL1-RBX1 E3 ubiquitin ligase complex that regulates the degradation of iron regulatory proteins (IRPs). Here, we describe a mechanism of FBXL5 regulation involving its interaction with the cytosolic Fe-S cluster assembly (CIA) targeting complex composed of MMS19, FAM96B, and CIAO1. We demonstrate that the CIA-targeting complex promotes the ability of FBXL5 to degrade IRPs. In addition, the FBXL5-CIA-targeting complex interaction is regulated by oxygen (O2) tension displaying a robust association in 21% O2 that is severely diminished in 1% O2 and contributes to O2-dependent regulation of IRP degradation. Together, these data identify a novel oxygen-dependent signaling axis that links IRP-dependent iron homeostasis with the Fe-S cluster assembly machinery.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proteínas F-Box/genética , Chaperonas Moleculares/genética , Complejos Multiproteicos/genética , Complejos de Ubiquitina-Proteína Ligasa/genética , Proteínas de Ciclo Celular/química , Proteínas F-Box/química , Células HeLa , Homeostasis , Humanos , Hierro/metabolismo , Proteínas Reguladoras del Hierro/genética , Proteínas Hierro-Azufre/química , Proteínas Hierro-Azufre/genética , Chaperonas Moleculares/química , Complejos Multiproteicos/química , Oxígeno/metabolismo , Proteolisis , Factores de Transcripción/genética , Complejos de Ubiquitina-Proteína Ligasa/química
20.
PLoS One ; 14(1): e0209435, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30625181

RESUMEN

Metformin, a widely prescribed anti-diabetic drug, shows anticancer activity in various cancer types. Few studies documented that there was a decreased level of LDL and total cholesterol in blood serum of metformin users. Based on these views, this study aimed to determine if metformin exhibits anticancer activity by alleviating cholesterol level in cancer cells. The present study found that treatment of breast cancer MDA-MB-231 cells with metformin significantly decreased cholesterol content with concomitant inhibition of various cholesterol regulatory genes (e.g., HMGCoR, LDLR and SREBP1). Metformin decreased cell viability, migration and stemness in metastatic MDA-MB-231 cells. Similarly, metformin treatment suppressed expressions of anti-apoptotic genes BCL2 and Bcl-xL, and mesenchymal genes vimentin, N-cadherin, Zeb1 and Zeb2 with simultaneous enhancement of apoptotic caspase 3 and Bax, and epithelial genes E-cadherin and keratin 19 expressions, confirming an inhibitory effect of metformin in tumorigenesis. Similar to metformin, depletion of cholesterol by methyl beta cyclodextrin (MBCD) diminished cell viability, migration, EMT and stemness in breast cancer cells. Moreover, metformin-inhibited cell viability, migration, colony and sphere formations were reversed back by cholesterol treatment. Similarly, cholesterol treatment inverted metformin-reduced several gene expressions (e.g., Bcl-xL, BCL2, Zeb1, vimentin, and BMI-1). Additionally, zymography data demonstrated that cholesterol upregulated metformin-suppressed MMP activity. These findings suggested that metformin revealed anticancer activity by lowering of cholesterol content in breast cancer cells. Thus, this study, for the first time, unravelled this additional mechanism of metformin-mediated anticancer activity.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Colesterol/metabolismo , Metformina/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colesterol/genética , Colesterol/farmacología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ensayo de Tumor de Célula Madre
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