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1.
J Chem Phys ; 161(14)2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39377339

RESUMEN

We investigate the two-dimensional behavior of colloidal patchy ellipsoids specifically designed to follow a two-step assembly process from the monomer state to mesoscopic liquid-crystal phases via the formation of the so-called bent-core units at the intermediate stage. Our model comprises a binary mixture of ellipses interacting via the Gay-Berne potential and decorated by surface patches, with the binary components being mirror-image variants of each other-referred to as left-handed and right-handed ellipses according to the position of their patches. The surface patches are designed so as in the first stage of the assembly the monomers form bent-cores units, i.e., V-shaped dimers with a specific bent angle. The Gay-Berne interactions, which act between the ellipses, drive the dimers to subsequently form the characteristic phase observed in bent-core liquid crystals. We numerically investigate-by means of both Molecular Dynamics and Monte Carlo simulations-the described two-step process: we first optimize a target bent-core unit and then fully characterize its state diagram in temperature and density, defining the regions where the different liquid crystalline phases dominate.

2.
Soft Matter ; 19(13): 2370-2376, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36920058

RESUMEN

Furukawa predicted that at late times, the domain growth in binary fluids scales as (t) ∼ t2/3, and the growth is driven by fluid inertia. The inertial growth regime has been highly elusive in molecular dynamics (MD) simulations. We perform coarsening studies of the (d = 3) Stockmayer (SM) model comprising of magnetic dipoles that interact via long-range dipolar interactions as well as the usual Lennard-Jones (LJ) potential. This fascinating polar fluid exhibits a gas-liquid phase coexistence, and magnetic order even in the absence of an external field. From comprehensive MD simulations, we observe the inertial scaling [(t) ∼ t2/3] in the SM fluid for an extended time window. Intriguingly, the fluid inertia is overwhelming from the outset - our simulations do not show the early diffusive regime [(t) ∼ t1/3] and the intermediate viscous regime [(t) ∼ t] prevalent in LJ fluids.

3.
Environ Monit Assess ; 191(6): 403, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31140016

RESUMEN

The magnetic susceptibility (MS) measurements are used for rapid and cost-effective soil surveys and for accessing heavy metal contamination worldwide. In the sub-Himalayan plains of India, nearly 6.05 × 104 km2 area of most the fertile land occurs as interfluve of Late Quaternary age between the two major glacier-fed rivers (Ganga and Yamuna). The vast areal expanse of interfluve terminates at the rivers' confluence in Sangam (25°25'13″N-81°53'22″E), Allahabad. This is the first study of MS soil survey of the interfluve region at the confluence comprising 490 samples from 49 locations. The MS values are between 8.84 and 261.25 × 10-8 m3 kg-1 and the change is more pronounced (8.84-312.65 × 10-8 m3 kg-1) with increasing depth. A sudden increase in the MS between 12- (11.28-303.32 × 10-8 m3 kg-1) and 14-cm (11.21-238.45 × 10-8 m3 kg-1) depth is observed similar to observations worldwide. The high MS hotspots are aligned parallel to major traffic networks of the city suggesting a major contribution emanating from the anthropogenic load. A significant difference has been noted in the MS values of present-day mid-channel bar sediments of Ganga (25.24 × 10-8 m3 kg-1) and Yamuna (116.47 × 10-8 m3 kg-1) Rivers. The laser-induced breakdown spectroscopy (LIBS) data showed the presence of heavy (Fe, Ti, Cr, Cu, Cd, Zn, and Pb) and light (H, C, N, and O) elements supporting MS data. The concentration of toxic elements predicted by partial least squares regression (PLSR) approach concurs with magnetic measurements. The topsoil MS values increase up to a depth of ~ 6.25 cm suggesting the dominant role of anthropogenic source for the increased heavy metal concentration compared with basement contributions.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Ríos/química , Contaminantes del Suelo/análisis , Suelo/química , Urbanización , Ciudades , India , Magnetometría/métodos , Análisis Espectral/métodos
4.
Diagnostics (Basel) ; 14(13)2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39001330

RESUMEN

New forms of interaction made possible by developments in special educational technologies can now help students with dyscalculia. Artificial intelligence (AI) has emerged as a promising tool in recent decades, particularly between 2001 and 2010, offering avenues to enhance the quality of education for individuals with dyscalculia. Therefore, the implementation of AI becomes crucial in addressing the needs of students with dyscalculia. Content analysis techniques were used to examine the literature covering the influence of AI on dyscalculia and its potential to assist instructors in promoting education for individuals with dyscalculia. The study sought to create a foundation for a more inclusive dyscalculia education in the future through in-depth studies. AI integration has had a big impact on educational institutions as well as people who struggle with dyscalculia. This paper highlights the importance of AI in improving the educational outcomes of students affected by dyscalculia.

5.
Phys Rev E ; 108(6-1): 064604, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38243485

RESUMEN

We study self-assembly in a colloidal suspension of magnetic particles by performing comprehensive molecular dynamics simulations of the Stockmayer (SM) model, which comprises spherical particles decorated by a magnetic moment. The SM potential incorporates dipole-dipole interactions along with the usual Lennard-Jones interaction and exhibits a gas-liquid phase coexistence observed experimentally in magnetic fluids. When this system is quenched from the high-temperature homogeneous phase to the coexistence region, the nonequilibrium evolution to the condensed phase proceeds with the development of spatial as well as magnetic order. We observe density-dependent coarsening mechanisms-a diffusive growth law ℓ(t)∼t^{1/3} in the nucleation regime and hydrodynamics-driven inertial growth law ℓ(t)∼t^{2/3} in the spinodal regimes. [ℓ(t) is the average size of the condensate at time t after the quench.] While the spatial growth is governed by the expected conserved order parameter dynamics, the growth of magnetic order in the spinodal regime exhibits unexpected nonconserved dynamics. The asymptotic morphologies have density-dependent shapes which typically include the isotropic sphere and spherical bubble morphologies in the nucleation region, and the anisotropic cylinder, planar slab, cylindrical bubble morphologies in the spinodal region. The structures are robust and nonvolatile, and exhibit characteristic magnetic properties. For example, the oppositely magnetized hemispheres in the spherical morphology impart the characteristics of a Janus particle to it. The observed structures have versatile applications in catalysis, drug delivery systems, memory devices, and magnetic photonic crystals, to name a few.

6.
Bioorg Med Chem Lett ; 21(6): 1706-9, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21320782

RESUMEN

An efficient one step synthesis of new 2-hydroxymethylisoflavone is reported. A series of deoxybenzoin was subjected to cyclization with glyoxal in the presence of basic condition (KOH/EtOH) to afford the 2-hydroxymethyl isoflavone. The structures of compounds 5a-g were confirmed by NMR experiments including (1)H, (13)C, HMBC, HSQC and COSY. These compounds were assessed for stimulation of osteoblast function using primary culture of rat calvarial osteoblasts in vitro. Compounds 5a, 5d, 5f and 5g were potent in stimulating differentiation of osteoblasts as assessed by measuring alkaline phosphatase (ALP) activity. Besides, effect of these analogs was also seen on the transcript levels of osteogenic genes like Runx-2, osteocalcin and Bone morphogenetic protein-2 (BMP-2), involved in osteoblast differentiation and mineralization. Based on quantitative PCR data, compound 5f was found to be the potent followed by 5d. Compound 5f robustly increased the mRNA levels of Runx-2 (8.0 fold), BMP-2 (∼2 fold) and osteocalcin (∼2.0 fold) in osteoblasts. Collectively, we demonstrate osteogenic activity of the novel 2-hydroxymethyl isoflavones with 5f having the most potent activity.


Asunto(s)
Isoflavonas/síntesis química , Osteogénesis/efectos de los fármacos , Animales , Células Cultivadas , Técnicas In Vitro , Isoflavonas/farmacología , Espectroscopía de Resonancia Magnética , Osteoblastos/citología , Osteoblastos/metabolismo , Ratas
7.
Life Sci ; 287: 120118, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34740574

RESUMEN

BACKGROUND: Highest incidence of oral cancer is reported in India with reduced survival rate in the advanced stages due to lack of effective biomarkers. Therefore, it is essential to develop novel biomarkers for the better management of this disease. In the current study, TNFAIP8/TIPE protein family comprising of four proteins is explored for its role in oral cancer. METHODS: IHC analysis of oral cancer TMA and Western blot analysis of tobacco treated oral cancer cells were performed to determine the differential expression of TIPE proteins in oral cancer. Further, CRISPR/Cas9-mediated gene editing was done to generate TIPE proteins' knockouts and MTT, colony formation, wound healing, cell cycle and Western blot analysis were performed to determine the effect of gene knockouts on various cancer hallmarks and the associated molecular targets of TIPE proteins. RESULTS AND DISCUSSION: IHC results revealed that expression of TIPE, TIPE2 and TIPE3 were upregulated and TIPE1 was downregulated in oral cancer tissues compared to normal tissues. Similar results were observed upon treating oral cancer cells with tobacco carcinogens. Furthermore, knockout of TIPE or TIPE2 or TIPE3 significantly reduced the survival, proliferation, colony formation and migration of oral cancer cells whereas knockout of TIPE1 had an opposite effect. Further, TIPE, TIPE2 and TIPE3 knockout-mediated inhibition of proliferation was associated with inhibition of cell cycle progression at S or G2/M phases, and downregulation of proteins involved in cancer progression. We found that TIPE, TIPE1 and TIPE2 proteins regulate oral cancer progression through modulation of Akt/mTOR signaling cascade, whereas TIPE3 acts through an Akt-independent mTOR/STAT3 pathway. CONCLUSION: Collectively, the TIPE proteins were proved to play significant roles in the progression of oral cancer thus warranting research and clinic attention for their therapeutic and prognostic values and raising the importance of specific targeting of TIPE proteins in cancer treatment.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Carcinogénesis/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas Proto-Oncogénicas c-akt/biosíntesis , Factor de Transcripción STAT3/biosíntesis , Serina-Treonina Quinasas TOR/biosíntesis , Proteínas Reguladoras de la Apoptosis/genética , Carcinogénesis/inducido químicamente , Carcinogénesis/genética , Carcinógenos/toxicidad , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/fisiología , Técnicas de Inactivación de Genes/métodos , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias de la Boca/genética , Proteínas Proto-Oncogénicas c-akt/genética , Factor de Transcripción STAT3/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/genética , Nicotiana/toxicidad
8.
Life Sci ; 261: 118372, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32882268

RESUMEN

Despite remarkable progress in understanding and treating oral cancer (OC), it still remains one of the life-threatening diseases and predominant cancers in the world. Therefore, deciphering the molecular mechanisms of this disease would help us to develop highly efficacious therapies. Multiple lines of evidence suggest that calcium and its dysregulation play significant role in the development of various cancers. As an adaptation of survival mechanism, upon depletion of ER calcium stores, store-operated calcium entry (SOCE) has been induced via SOCE channels (SOCC) in various mammalian cells. SOCC are regulated by Orai-1, Orai-2 and Orai-3 located on plasma membrane and two calcium-sensing ER membrane proteins known as stromal interaction molecules (STIM-1 and STIM-2). Hence, the present study was aimed at analysing the role of Orai-1 and Orai-2 in oral cancer and the underlying mechanism. Our results suggest that both Orai-1 and Orai-2 proteins were overexpressed in oral cancer tissues and cell lines (SAS) compared to normal epithelial tissues and cell lines respectively. In addition, silencing of Orai-1 and Orai-2 via chemical SOCE inhibitors and siRNAs inhibited calcium uptake and suppressed oral cancer cell proliferation, colony formation and migration. Furthermore, silencing of Orai-1 and Orai-2 inhibited Akt/mTOR/NF-κB pathway in oral cancer cells. Interestingly, tobacco carcinogen NNN and synthetic carcinogen 4-NQO, enhanced the expression of Orai-1 and Orai-2 in SAS cells. Therefore, we conclude that Orai-1 and Orai-2 have significant role in oral cancer and can be further explored to develop novel therapies for the treatment of this disease.


Asunto(s)
Movimiento Celular , Neoplasias de la Boca/patología , FN-kappa B/metabolismo , Proteína ORAI1/metabolismo , Proteína ORAI2/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Calcio/metabolismo , Señalización del Calcio , Carcinógenos/toxicidad , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Humanos , Neoplasias de la Boca/genética , Transducción de Señal/efectos de los fármacos , Nicotiana/química , Ensayo de Tumor de Célula Madre
9.
Biomolecules ; 9(12)2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31817720

RESUMEN

Lung cancer represents the most common cause of cancer deaths in the world, constituting around 11.6% of all new cancer cases and 18.4% of cancer-related deaths. The propensity for early spread, lack of suitable biomarkers for early diagnosis, as well as prognosis and ineffective existing therapies, contribute to the poor survival rate of lung cancer. Therefore, there is an urgent need to develop novel biomarkers for early diagnosis and prognosis which in turn can facilitate newer therapeutic avenues for the management of this aggressive neoplasm. TIPE2 (tumor necrosis factor-α-induced protein 8-like 2), a recently identified cytoplasmic protein, possesses enormous potential in this regard. Immunohistochemical analysis showed that TIPE2 was significantly upregulated in different stages and grades of lung cancer tissues compared to normal lung tissues, implying its involvement in the positive regulation of lung cancer. Further, knockout of TIPE2 resulted in significantly reduced proliferation, survival, and migration of human lung cancer cells through modulation of the Akt/mTOR/NF-κB signaling axis. In addition, knockout of TIPE2 also caused arrest in the S phase of the cell cycle of lung cancer cells. As tobacco is the most predominant risk factor for lung cancer, we therefore evaluated the effect of TIPE2 in tobacco-mediated lung carcinogenesis as well. Our results showed that TIPE2 was involved in nicotine-, nicotine-derived nitrosamine ketone (NNK)-, N-nitrosonornicotine (NNN)-, and benzo[a]pyrene (BaP)-mediated lung cancer through inhibited proliferation, survival, and migration via modulation of nuclear factor kappa B (NF-κB)- and NF-κB-regulated gene products, which are involved in the regulation of diverse processes in lung cancer cells. Taken together, TIPE2 possesses an important role in the development and progression of lung cancer, particularly in tobacco-promoted lung cancer, and hence, specific targeting of it holds an enormous prospect in newer therapeutic interventions in lung cancer. However, these findings need to be validated in the in vivo and clinical settings to fully establish the diagnostic and prognostic importance of TIPE2 against lung cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Neoplasias Pulmonares , Biomarcadores de Tumor/genética , Carcinogénesis , Línea Celular Tumoral , Proliferación Celular , Silenciador del Gen , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Nicotiana
10.
Biomolecules ; 9(7)2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31252679

RESUMEN

Protein kinase B (Akt) plays a very significant role in various cancers including oral cancer. However, it has three isoforms (Akt1, Akt2, and Akt3) and they perform distinct functions and even play contrasting roles in different cancers. Therefore, it becomes essential to evaluate the isoform-specific role of Akt in oral cancer. In the present study, an attempt has been made to elucidate the isoform-specific role of Akt in oral cancer. The immunohistochemical analysis of oral cancer tissues showed an overexpression of Akt1 and 2 isoforms but not Akt3. Moreover, the dataset of "The Cancer Genome Atlas" for head and neck cancer has suggested the genetic alterations of Akt1 and 2 tend to be associated with the utmost poor clinical outcome in oral cancer. Further, treatment of oral cancer cells with tobacco and its components such as benzo(a)pyrene and nicotine caused increased mRNA levels of Akt1 and 2 isoforms and also enhanced the aggressiveness of oral cancer cells in terms of proliferation, and clonogenic and migration potential. Finally, silencing of Akt1 and 2 isoforms caused decreased cell survival and induced cell cycle arrest at the G2/M phase. Akt1/2 silencing also reduced tobacco-induced aggressiveness by decreasing the clonogenic and migration potential of oral cancer cells. Moreover, silencing of Akt1 and 2 isoforms was found to decrease the expression of proteins regulating cancer cell survival and proliferation such as cyclooxygenase-2, B-cell lymphoma 2 (Bcl-2), cyclin D1, and survivin. Thus, the important role of Akt1 and 2 isoforms have been elucidated in oral cancer with in-depth mechanistic analysis.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Carcinoma de Células Escamosas/patología , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Humanos , Inmunohistoquímica , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Neoplasias de la Boca/patología , Nicotina/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/genética , Nicotiana/efectos adversos , Productos de Tabaco/efectos adversos , Células Tumorales Cultivadas
11.
Menopause ; 19(8): 856-63, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22781783

RESUMEN

OBJECTIVE: Formononetin (Formo) prevents ovariectomy (Ovx)-induced bone loss in rats. However, there are no reports on the curative effects of Formo. The objective of this study was to investigate the ability of Formo in restoring trabecular microarchitecture and promoting new bone formation in osteopenic rats. METHODS: Adult Sprague-Dawley rats were ovariectomized and left for 90 days for osteopenia to develop. After 90 days, Formo (10.0 mg kg d) was given orally for the next 12 weeks to Ovx rats in a therapeutic protocol. Sham-operated, Ovx + vehicle, and Ovx + parathyroid hormone (PTH) groups served as controls. Trabecular microarchitecture, osteoid formation, bone turnover/resorption markers, and bone osteoprotegerin-to-receptor activator for nuclear κB ligand ratio were studied. One-way analysis of variance was used to test significance of effects. RESULTS: Formo treatment significantly restored the lost trabecular microarchitecture in the femurs and tibia of osteopenic Ovx rats and promoted new bone formation. Formo was devoid of any uterine estrogenicity. Serum levels of type I collagen N-terminal propeptide, which is a reliable marker of bone formation, were increased in Ovx rats treated with Formo compared with Ovx + vehicle group, and the levels were comparable with those in the sham group. Formo prevented the Ovx-induced increase in bone turnover markers, including serum osteocalcin and urinary type I collagen degradation product. Furthermore, Formo-treated Ovx rats had an increased bone osteoprotegerin-to-receptor activator for nuclear κB ligand ratio compared with the Ovx + vehicle group. CONCLUSIONS: Daily oral administration of Formo for 12 weeks has a substantial anabolic effect, thus raising the possibility of its use in postmenopausal osteoporosis.


Asunto(s)
Enfermedades Óseas Metabólicas/tratamiento farmacológico , Isoflavonas/administración & dosificación , Ovariectomía , Fitoestrógenos/administración & dosificación , Animales , Enfermedades Óseas Metabólicas/etiología , Enfermedades Óseas Metabólicas/patología , Remodelación Ósea/efectos de los fármacos , Femenino , Fémur/patología , Osteogénesis/efectos de los fármacos , Osteoprotegerina/genética , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Ligando RANK/genética , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Tibia/patología
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