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2.
Int J Pharm ; 656: 124078, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38569978

RESUMEN

The role of tumor stroma in solid tumors has been widely recognized in cancer progression, metastasis and chemoresistance. Cancer-associated fibroblasts (CAFs) play a crucial role in matrix remodeling and promoting cancer cell stemness and resistance via reciprocal crosstalk. Residual tumor tissue after surgical removal as well as unresectable tumors face therapeutic challenges to achieve curable outcome. In this study, we propose to develop a dual delivery approach by combining p21-activated kinase 1 (PAK1) inhibitor (FRAX597) to inhibit tumor stroma and chemotherapeutic agent paclitaxel (PTX) to kill cancer cells using electrospun nanofibers. First, the role of the PAK1 pathway was established in CAF differentiation, migration and contraction using relevant in vitro models. Second, polycaprolactone polymer-based nanofibers were fabricated using a uniaxial electrospinning technique to incorporate FRAX597 and/or PTX, which showed a uniform texture and a prolonged release of both drugs for 16 days. To test nanofibers, stroma-rich 3D heterospheroid models were set up which showed high resistance to PTX nanofibers compared to stroma-free homospheroids. Interestingly, nanofibers containing PTX and FRAX597 showed strong anti-tumor effects on heterospheroids by reducing the growth and viability by > 90 % compared to either of single drug-loaded nanofibers. These effects were reflected by reduced intra-spheroidal expression levels of collagen 1 and α-smooth muscle actin (α-SMA). Overall, this study provides a new therapeutic strategy to inhibit the tumor stroma using PAK1 inhibitor and thereby enhance the efficacy of chemotherapy using nanofibers as a local delivery system for unresectable or residual tumor. Use of 3D models to evaluate nanofibers highlights these models as advanced in vitro tools to study the effect of controlled release local drug delivery systems before animal studies.


Asunto(s)
Nanofibras , Paclitaxel , Quinasas p21 Activadas , Paclitaxel/administración & dosificación , Paclitaxel/farmacología , Nanofibras/administración & dosificación , Quinasas p21 Activadas/antagonistas & inhibidores , Quinasas p21 Activadas/metabolismo , Humanos , Línea Celular Tumoral , Esferoides Celulares/efectos de los fármacos , Poliésteres/química , Poliésteres/administración & dosificación , Fibroblastos Asociados al Cáncer/efectos de los fármacos , Fibroblastos Asociados al Cáncer/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Movimiento Celular/efectos de los fármacos , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/farmacología , Liberación de Fármacos , Diferenciación Celular/efectos de los fármacos
3.
J Mater Chem B ; 12(12): 2950-2984, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38426529

RESUMEN

Thin-film nano-architecting is a promising approach that controls the properties of nanoscale surfaces to increase their interdisciplinary applications in a variety of fields. In this context, zinc oxide (ZnO)-based various nano-architectures (0-3D) such as quantum dots, nanorods/nanotubes, nanothin films, tetrapods, nanoflowers, hollow structures, etc. have been extensively researched by the scientific community in the past decade. Owing to its unique surface charge transport properties, optoelectronic properties and reported biomedical applications, ZnO has been considered as one of the most important futuristic bio-nanomaterials. This review is focused on the design/synthesis and engineering of 0-3D nano-architecture ZnO-based thin films and coatings with tunable characteristics for multifunctional biomedical applications. Although ZnO has been extensively researched, ZnO thin films composed of 0-3D nanoarchitectures with promising thin film device bio-nanotechnology applications have rarely been reviewed. The current review focuses on important details about the technologies used to make ZnO-based thin films, as well as the customization of properties related to bioactivities, characterization, and device fabrication for modern biomedical uses that are relevant. It features biosensing, tissue engineering/wound healing, antibacterial, antiviral, and anticancer activity, as well as biomedical diagnosis and therapy with an emphasis on a better understanding of the mechanisms of action. Eventually, key issues, experimental parameters and factors, open challenges, etc. in thin film device fabrications and applications, and future prospects will be discussed, followed by a summary and conclusion.


Asunto(s)
Nanoestructuras , Nanotubos , Óxido de Zinc , Óxido de Zinc/química , Nanotecnología , Nanotubos/química , Nanoestructuras/química , Propiedades de Superficie
4.
Dalton Trans ; 53(14): 6245-6255, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38498176

RESUMEN

The design of new complex mixed metal tellurides (containing low toxicity cations) with intrinsic ultralow thermal conductivity is of paramount importance in the field of thermoelectrics. Herein, we report the synthesis and characterization of polycrystalline and single crystals of a new mixed-metal quaternary telluride Mn1.8(1)In0.8(1)Si2Te6. The structural aspects and chemical formula of this phase at room temperature have been established using single crystal X-ray diffraction and EDX studies. The trigonal centrosymmetric (space group: P3̄1m) structure of the title phase has cell constants of a = b = 7.0483(7) Å and c = 7.1277(8) Å. The structure has three independent cationic sites, one mixed (In1/Mn1), one partially filled Mn2, and one Si1, which are bonded with Te1 atoms. Each metal atom (In and Mn) in the structure is octahedrally coordinated with six neighboring Te1 atoms. The structure also features dimers of Si atoms, and each Si atom is bonded to three Te1 atoms to form ethane-like Si2Te6 units. The optical absorption study of a polycrystalline Mn1.8In0.8Si2Te6 sample shows a narrow optical bandgap of 0.6(2) eV. Temperature-dependent resistivity and Seebeck coefficient studies confirmed the p-type semiconducting nature of the sample with high values of S (301 µV K-1 to 444 µV K-1). The total thermal conductivity (ktot) study of the polycrystalline sample shows a decreasing trend on heating with an extremely low value of 0.28 W m-1 K-1 at 773 K. Magnetic measurements indicate a glassy magnetic behavior for the sample below 8 K.

5.
Front Plant Sci ; 15: 1353808, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38463567

RESUMEN

The knowledge of pollen morphology, suitable storage condition, and species compatibility is vital for a successful grapevine improvement programme. Ten grape genotypes from three different species, viz., Vitis vinifera L., Vitis parviflora Roxb., and Vitis champini Planc., were studied for their pollen structure and pollen storage with the objective of determining their utilization in grape rootstock improvement programs. Pollen morphology was examined through the use of a scanning electron microscope (SEM). The viability of the pollen was assessed using 2,3,5-triphenyltetrazolium chloride (TTC). In vitro pollen germination was investigated using the semi-solid medium with 10 % sucrose, 100 mg/L boric acid, and 300 mg/L calcium nitrate. The results revealed variations in pollen micro-morphology in 10 genotypes, with distinct pollen dimensions, shapes, and exine ornamentation. However, species-wise, no clear difference was found for these parameters. Pollen of V. parviflora Roxb. and Dogridge was acolporated and did not germinate. The remaining eight genotypes exhibited tricolporated pollen and showed satisfactory in vitro pollen germination. Storage temperature and duration interactions showed that, at room temperature, pollen of most of the grape genotypes can be stored for up to 1 day only with an acceptable pollen germination rate (>30 %). However, storage for up to 7 days was successfully achieved at 4 °C, except for 'Pearl of Csaba'. The most effective storage conditions were found to be at -20 °C and -196 °C (in liquid N2), enabling pollen storage for a period of up to 30 days, and can be used for pollination to overcome the challenge of asynchronous flowering. Four interspecific combinations were studied for their compatibility, among which V. parviflora Roxb. × V. vinifera L. (Pusa Navrang) and V. parviflora Roxb. × V. champini Planc. (Salt Creek) showed high cross-compatibility, offering their potential use for grape rootstock breeding. However, V. parviflora Roxb. × V. vinifera L. (Male Hybrid) recorded the lowest compatibility index among studied crosses. In the case of self-pollinated flowers from V. parviflora Roxb. and V. parviflora Roxb. × V. champini Planc. (Dogridge), pollen failed to germinate on the stigma due to male sterility caused by acolporated pollen. As a result, the flowers of these genotypes functioned as females, which means they are ideal female parents for grape breeding without the need for the tedious process of emasculation.

6.
Heliyon ; 10(3): e24808, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38317968

RESUMEN

Glioblastoma multiforme (GBM), a highly aggressive tumor type with a dismal survival rate, has a poor outcome which is at least partly attributed to the crosstalk between cancer cells and cells from the tumor microenvironment such as astrocytes and microglia. We aimed to decipher the effect of these cells on GBM progression and on cell-based therapies using 3D co-cultures. Co-culturing of glioblastoma cells with patient-derived astrocytes or microglia or both formed dense and heterogeneous spheroids. Both, astrocytes and microglia, enhanced the spheroid growth rate and formed a physical barrier for macromolecules penetration, while only astrocytes enhanced the migration. Interestingly bi-/tri-cultured spheroids showed significant resistance against NK-92 cells, likely attributed to dense stroma and induced expression of immunosuppressive genes such as IDO1 or PTGES2. Altogether, our novel 3D GBM spheroid model recapitulates the cell-to-cell interactions of human glioblastoma and can serve as a suitable platform for evaluating cancer therapeutics.

7.
Chemosphere ; 352: 141483, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38378052

RESUMEN

Contaminants of emerging concern (CEC) contain a wide range of compounds, such as pharmaceutical waste, pesticides, herbicides, industrial chemicals, organic dyes, etc. Their presence in the surrounding has extensive and multifaceted effects on human health as they have the potential to persist in the environment, accumulate in biota, and disrupt ecosystems. In this regard, various remediation methods involving different kind of functional nanomaterials with unique properties have been developed. The functional nanomaterials can provide several mechanisms for water pollutant removal, such as adsorption, catalysis, and disinfection, in a single platform. Graphene oxide (GO) is a two-dimensional carbon-based material that has an extremely large surface area and a large number of active sites. Recent advances in synthesising GO have shown great progress in tailoring its various physiochemical, optical, surface, structural properties etc., making it better adsorbent and photocatalysts. In this review, sole adsorbent and standalone photocatalytic performances of GO for the removal of CEC have been discussed in light of tailoring its adsorption and photocatalytic properties through novel synthesis routes and optimizing synthesis parameters. This review also examines various models describing the structure of GO and its surface/structural modifications for improved adsorption and photocatalytic properties. The article provides valuable information for the production of efficient and cost-effective GO-based sole adsorbents and photocatalysts as compared to the traditional materials. Furthermore, future prospective and challenges for sole GO nanostructures to compete with traditional adsorbents and photocatalysts have been discussed providing interesting avenues for future research.


Asunto(s)
Grafito , Nanoestructuras , Humanos , Ecosistema , Grafito/química , Carbono , Adsorción
9.
Acta Crystallogr C Struct Chem ; 80(Pt 1): 9-14, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38163291

RESUMEN

We report the structural characterization of a new quaternary telluride, Ba2Y0.87(1)Mn1.71(1)Te5, which was synthesized by the direct reaction of the elements inside a vacuum-sealed fused-silica tube. The quaternary phase is the first member of the Ba-M-Mn-Te system (M = Sc and Y). The composition and structure of the phase were elucidated using SEM-EDX (scanning electron microscopy-energy dispersive X-ray spectrometry) and single-crystal X-ray diffraction (SCXRD) studies. The title phase is nonstoichiometric and crystallizes in the monoclinic system (space group C2/m) having the refined unit-cell parameters a = 15.1466 (8), b = 4.5782 (3), c = 10.6060 (7) Šand ß = 116.956 (2)°, with two formula units (Z = 2). The pseudo-two-dimensional crystal structure of Ba2Y0.87(1)Mn1.71(1)Te5 consists of distorted YTe6 octahedra and MnTe4 tetrahedra as the building blocks of the structure. The YTe6 octahedra are arranged to form infinite one-dimensional chains by sharing edges along the [010] direction. These chains are further connected to the MnTe4 tetrahedra along the c axis to create layered two-dimensional polyanionic [Y0.87(1)Mn1.71(1)Te5]4- units. The stuffing of Ba2+ cations in between the layers of [Y0.87(1)Mn1.71(1)Te5]4- anions brings the charge neutrality of the structure. Each Ba atom in the structure sits at the centre of a distorted monocapped trigonal prism-like polyhedron of seven Te atoms.

10.
ACS Omega ; 8(49): 46628-46639, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38107962

RESUMEN

The development and design of pharmaceutical cocrystals for various biological applications has garnered significant interest. In this study, we have established methodologies for the growth of the methylparaben-quinidine cocrystal (MP-QU), which exhibits a well-defined order that favors structure-property correlation. To confirm the cocrystal formation, we subjected the cocrystals to various physicochemical analyses such as powder X-ray diffraction (PXRD), single-crystal X-ray diffraction (SCXRD), Raman, and IR spectroscopy. The results of the XRD pattern comparisons indicated no polymorphisms, and density functional theory (DFT) studies in both gaseous and liquid phases revealed enhanced stability. Our in silico docking studies demonstrated the cocrystal's high-affinity binding towards cancer-specific epidermal growth factor receptor (EGFR), Janus kinase (JAK), and other receptors. Furthermore, in vitro testing against three-dimensional (3D) spheroids of lung cancer (A549) and normal fibroblast cells (L929) demonstrated the cocrystal's higher anticancer potential, supported by cell viability measurements and live/dead assays. Interestingly, the cocrystal showed selectivity between cancerous and normal 3D spheroids. We found that the MP-QU cocrystal inhibited migration and invadopodia formation of cancer spheroids in a favorable 3D microenvironment.

11.
Int J Pharm ; 644: 123348, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37633539

RESUMEN

Small interfering RNAs (siRNAs) are promising therapeutics for the treatment of human diseases via the induction of sequence-specific gene silencing. To be functional, siRNAs require cytosolic delivery into target cells. However, state-of-the-art delivery systems mediate cellular entry through endocytosis and suffer from ineffective endosomal escape, routing a substantial fraction of the siRNA towards the lysosomal compartment. Cationic amphiphilic drugs (CADs) have been described to improve cytosolic siRNA delivery by the transient induction of lysosomal membrane permeabilization. In this work, we evaluated ebastine, an antihistamine CAD, for its ability to enhance cytosolic release of siRNA in a non-small cell lung cancer model. In particular, we demonstrated that ebastine can improve the siRNA-mediated gene silencing efficiency of a polymeric nanogel by 40-fold, outperforming other CAD compounds. Additionally, ebastine substantially enhanced gene knockdown of a cholesterol-conjugated siRNA, in two-dimensional (2D) cell culture as well as in three-dimensional (3D) tumor spheroids. Finally, ebastine could strongly promote siRNA delivery of lipid nanoparticles (LNPs) composed of a pH-dependent switchable ionizable lipid and with stable PEGylation, in contrast to state-of-the-art LNP formulations. Altogether, we identified ebastine as a potent and versatile siRNA delivery enhancer in cancer cells, which offers opportunities for drug combination therapy in oncology.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , ARN Interferente Pequeño , Antagonistas de los Receptores Histamínicos
12.
Dalton Trans ; 52(42): 15426-15439, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37376920

RESUMEN

Heavier pnictogen (Sb, Bi) containing chalcogenides are well known for their complex structures and semiconducting properties for numerous applications, particularly thermoelectric materials. Here, we report the syntheses of single crystals and polycrystalline phases of a new complex quaternary polytelluride, Ba14Si4Sb8Te32(Te3), via a high-temperature reaction of elements. A single-crystal X-ray diffraction study showed that it crystallizes in an unprecedented structure type with monoclinic symmetry (space group: P21/c). The crystal structure of Ba14Si4Sb8Te32(Te3) consists of one-dimensional ∞1[Si4Sb8Te32(Te3)]28- stripes, which are separated by the Ba2+ cations. Its complex structure features linear polytelluride units of Te34- having intermediate Te⋯Te interactions. A polycrystalline Ba14Si4Sb8Te32(Te3) sample shows a direct narrow bandgap of 0.8(2) eV, which indicates its semiconducting nature. The electrical resistivity of a sintered pellet of the polycrystalline sample exponentially decreases from ∼39.3 Ωcm to ∼0.57 Ωcm on heating it from 323 K to 773 K, confirming the sample's semiconducting nature. The sign of Seebeck coefficient values is positive in the 323 K to 773 K range confirming the p-type nature of the sintered sample. Interestingly, the sample attains an extremely low thermal conductivity of ∼0.32 Wm-1K-1 at 773 K, which could be attributed to the lattice anharmonicity caused by the lone pair effect of Sb3+ species in its complex pseudo-one-dimensional crystal structure. The electronic band structure of the title phase and the strength of chemical bonding of pertinent atomic pairs have been evaluated theoretically using the DFT method.

13.
Cancers (Basel) ; 15(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36831470

RESUMEN

Cancer-associated fibroblasts (CAFs) are important drivers in the tumor microenvironment and facilitate the growth and survival of tumor cells, as well as metastasis formation. They may travel together with tumor cells to support their survival and aid in the formation of a metastatic niche. In this study, we aimed to study circulating CAFs (cCAFs) and circulating tumor cells (CTCs) in a preclinical breast tumor model in mice in order to understand the effect of chemotherapy on cCAFs and CTC formation. Tumors with MDA-MB-231 human breast tumor cells with/without primary human mammary fibroblasts (representing CAFs) were coinjected in SCID mice to develop tumors. We found that the tumors with CAFs grew faster than tumors without CAFs. To study the effect of the stroma on CTCs and cCAFs, we isolated cells using microsieve filtration technology and established ITGA5 as a new cCAF biomarker, which showed good agreement with the CAF markers FAP and α-SMA. We found that ITGA5+ cCAFs shed in the blood of mice bearing stroma-rich coinjection-based tumors, while there was no difference in CTC formation. Although treatment with liposomal doxorubicin reduced tumor growth, it increased the numbers of both cCAFs and CTCs in blood. Moreover, cCAFs and CTCs were found to form clusters in the chemotherapy-treated mice. Altogether, these findings indicate that the tumor stroma supports tumor growth and the formation of cCAFs. Furthermore, chemotherapy may exacerbate the formation of cCAFs and CTCs, which may eventually support the formation of a metastasis niche in breast cancer.

14.
Drug Deliv Transl Res ; 13(5): 1470-1483, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36853438

RESUMEN

Since tumor stroma poses as a barrier to achieve efficacy of nanomedicines, it is essential to evaluate nano-chemotherapeutics in stroma-mimicking 3D models that reliably predict their behavior regarding these hurdles limiting efficacy. In this study, we evaluated the effect of paclitaxel-loaded polymeric micelles (PTX-PMCs) and polymeric nanoparticles (PTX-PNPs) in a tumor stroma-mimicking 3D in vitro model. PTX-PMCs (77 nm) based on a amphiphilic block copolymer of mPEG-b-p(HPMAm-Bz) and PTX-PNPs (159 nm) based on poly(lactic-co-glycolic acid) were prepared, which had an encapsulation efficiency (EE%) of 81 ± 15% and 45 ± 8%, respectively. 3D homospheroids of mouse 4T1 breast cancer cells and heterospheroids of NIH3T3 fibroblasts and 4T1 (5:1 ratio) were prepared and characterized with high content two-photon microscopy and immunostaining. Data showed an induction of epithelial-mesenchymal transition (α-SMA) in both homo- and heterospheroids, while ECM (collagen) deposition only in heterospheroids. Two-photon imaging revealed that both fluorescently labeled PMCs and PNPs penetrated into the core of homospheroids and only PMCs penetrated into heterospheroids. Furthermore, PTX-PMCs, PTX-PNPs, and free PTX induced cytotoxicity in tumor cells and fibroblasts grown as monolayer, but these effects were substantially reduced in 3D models, in particular in heterospheroids. Gene expression analysis showed that heterospheroids had a significant increase of drug resistance markers (Bcl2, Abgc2) compared to 2D or 3D monocultures. Altogether, this study shows that the efficacy of nanotherapeutics is challenged by stroma-induced poor penetration and development of resistant phenotype. Therefore, this tumor stroma-mimicking 3D model can provide an excellent platform to study penetration and effects of nanotherapeutics before in vivo studies.


Asunto(s)
Nanopartículas , Neoplasias , Ratones , Animales , Paclitaxel/farmacología , Células 3T3 NIH , Polímeros/uso terapéutico , Neoplasias/tratamiento farmacológico , Polietilenglicoles/uso terapéutico , Micelas , Línea Celular Tumoral , Portadores de Fármacos/uso terapéutico
15.
Environ Sci Pollut Res Int ; 30(12): 34054-34068, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36508093

RESUMEN

The development of efficient nanomaterials with promising optical and surface properties for multifunctional applications has always been a subject of novel research. In this work, the study of highly efficient TiO2 nanorods (NRs) and Ta-doped TiO2 NRs (Ta-TiO2 NRs) synthesized by alkaline hydrothermal treatment followed by soaking treatment has been reported. NRs were investigated for their potential applications as recyclable/reproducible visible light active photocatalysts and surface-enhanced Raman scattering (SERS) substrates in wastewater treatment. NRs were characterized by various microscopic (scanning and transmission electron microscopy), spectroscopic (X-ray diffraction, X-ray photoelectron, UV-visible, photoluminescence, and Raman spectroscopy), and surface (Brunauer-Emmett-Teller) techniques. The NRs exhibited promising optical properties with a band gap of 2.95 eV (TiO2 NRs) and 2.58 eV (Ta-TiO2 NRs) showing excellent photo-degradation activities for methylene blue (MB) dye molecules under natural sunlight. Particularly, Ta-TiO2 NRs showed enhanced response as visible light active photocatalysts in normal sunlight and also as SERS substrate attributed to the additional defects introduced by Ta doping. It could be explained by the combined effect of doping-induced enhanced visible light absorption and charge transfer (CT) properties of Ta-TiO2 NRs. Furthermore, Ta-TiO2 NRs were investigated for their long-term stability, reproducibility of the data, and recyclability in view of their potential applications in water treatment.


Asunto(s)
Luz , Purificación del Agua , Reproducibilidad de los Resultados , Titanio/química , Óxidos , Purificación del Agua/métodos
16.
Dalton Trans ; 52(3): 621-634, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36426633

RESUMEN

The single crystals of a quaternary sulfide, Ba4FeAgS6, have been synthesized by reacting elements at 873 K inside a sealed fused silica tube. The title phase is the first ordered quaternary compound of the Ba-Ag-Fe-S system. The crystal structure of Ba4FeAgS6 is characterized by a single-crystal X-ray diffraction study at 298(2) K. It crystallizes in the space group C52h - P21/n of the monoclinic crystal system with unit cell dimensions of a = 8.6367(5) Å, b = 12.0291(7) Å, c = 13.2510(7) Å, and ß = 109.015(2)°. This compound is stoichiometric, and its structure contains twelve unique crystallographic sites: four Ba, one Fe, one Ag, and six S sites. All atoms of the structure occupy the general positions. The Ba4FeAgS6 structure consists of one-dimensional chains of 1∞[FeAgS6]8- that are extended in the [100] direction. The negative charges on these chains are counterbalanced by the filling of Ba2+ cations in between the 1∞[FeAgS6]8- chains. The Fe atoms are bonded to four S atoms that form a distorted tetrahedral geometry around the central Fe atom. Each Ag atom in this structure is coordinated with four S atoms in a distorted tetrahedral fashion. These FeS4 and AgS4 motifs are the main building blocks of the Ba4FeAgS6 structure. The corner-sharing of FeS4 and AgS4 tetrahedra creates one-dimensional chains of 1∞[FeAgS6]8-. This structure does not contain any homoatomic or metallic bonds and can be charge-balanced as (Ba2+)4(Fe3+)1(Ag1+)1(S2-)6. The optical absorption study performed on a polycrystalline Ba4FeAgS6 sample reveals a direct bandgap of 1.2(1) eV. The magnetic studies reveal the antiferromagnetic behavior of Ba4FeAgS6 below 50 K. The thermal conductivity and theoretical electronic structure of Ba4FeAgS6 are also studied in detail.

17.
Kidney Int ; 103(2): 264-281, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36481180

RESUMEN

Our understanding of the various aspects of pregnancy in women with kidney diseases has significantly improved in the last decades. Nevertheless, little is known about specific kidney diseases. Glomerular diseases are not only a frequent cause of chronic kidney disease in young women, but combine many challenges in pregnancy: immunologic diseases, hypertension, proteinuria, and kidney tissue damage. An international working group undertook the review of available current literature and elicited expert opinions on glomerular diseases in pregnancy with the aim to provide pragmatic information for nephrologists according to the present state-of-the-art knowledge. This work also highlights areas of clinical uncertainty and emphasizes the need for further collaborative studies to improve maternal and fetal health.


Asunto(s)
Complicaciones del Embarazo , Insuficiencia Renal Crónica , Embarazo , Femenino , Humanos , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/terapia , Complicaciones del Embarazo/etiología , Toma de Decisiones Clínicas , Incertidumbre , Riñón , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Insuficiencia Renal Crónica/complicaciones , Resultado del Embarazo
18.
Biomater Adv ; 144: 213220, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36476713

RESUMEN

The rapid developments in biofabrication, in particular 3D bioprinting, in the recent years have facilitated the need for novel biomaterials that aim to replicate the target tissue in great detail. The presence of endotoxins in these biomaterials is often an overlooked problem. In pre-clinical 3D in vitro models, endotoxins can have significant influence on cell behavior and credibility of the model. In this study we demonstrate the effects of high levels of endotoxins in commercially-available gelatin on the macrophage-cancer cell crosstalk in a 3D bioprinted co-culture model. First, it is demonstrated that, while presenting the same mechanical and structural stimuli, high levels of endotoxin can have significant influence on the metabolic activity of macrophages and cancer cells. Furthermore, this study shows that high endotoxin contamination causes a strong inflammatory reaction in macrophages and significantly inhibits the effects of a paracrine macrophage-cancer cell co-culture. At last, it is demonstrated that the differences in endotoxin levels can drastically alter the efficacy of novel macrophage modulating immunotherapies, AS1517499 and 3-methyladenine. Altogether, this study shows that endotoxin contamination in biomaterials can significantly alter intra- and intercellular communication and thereby drug efficacy, which might lead to misinterpretation of the potency and safety of the tested compounds.


Asunto(s)
Endotoxinas , Neoplasias , Endotoxinas/metabolismo , Endotoxinas/farmacología , Macrófagos , Técnicas de Cocultivo , Materiales Biocompatibles/farmacología , Comunicación Celular , Neoplasias/metabolismo
19.
Bioact Mater ; 22: 18-33, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36203956

RESUMEN

Fibrotic tumors, such as pancreatic ductal adenocarcinoma (PDAC), are characterized for high desmoplastic reaction, which results in high intra-tumoral solid stress leading to the compression of blood vessels. These microarchitectural alterations cause loss of blood flow and poor intra-tumoral delivery of therapeutics. Currently, there is a lack of relevant in vitro models capable of replicating these mechanical characteristics and to test anti-desmoplastic compounds. Here, a multi-layered vascularized 3D PDAC model consisting of primary human pancreatic stellate cells (PSCs) embedded in collagen/fibrinogen (Col/Fib), mimicking tumor tissue within adjunct healthy tissue, is presented to study the fibrosis-induced compression of vasculature in PDAC. It is demonstrated how the mechanical and biological stimulation induce PSC activation, extracellular matrix production and eventually vessel compression. The clinical relevance is confirmed by correlating with patient transcriptomic data. Furthermore, the effects of gradual vessel compression on the fluid dynamics occurring within the channel is evaluated in silico. Finally, it is demonstrated how cancer-associated fibroblast (CAF)-modulatory therapeutics can inhibit the cell-mediated compression of blood vessels in PDAC in vitro, in silico and in vivo. It is envisioned that this 3D model is used to improve the understanding of mechanical characteristics in tumors and for evaluating novel anti-desmoplastic therapeutics.

20.
Front Plant Sci ; 13: 1022167, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36578327

RESUMEN

Low-temperature stress (LTS) drastically affects vegetative and reproductive growth in fruit crops leading to a gross reduction in the yield and loss in product quality. Among the fruit crops, temperate fruits, during the period of evolution, have developed the mechanism of tolerance, i.e., adaptive capability to chilling and freezing when exposed to LTS. However, tropical and sub-tropical fruit crops are most vulnerable to LTS. As a result, fruit crops respond to LTS by inducing the expression of LTS related genes, which is for climatic acclimatization. The activation of the stress-responsive gene leads to changes in physiological and biochemical mechanisms such as photosynthesis, chlorophyll biosynthesis, respiration, membrane composition changes, alteration in protein synthesis, increased antioxidant activity, altered levels of metabolites, and signaling pathways that enhance their tolerance/resistance and alleviate the damage caused due to LTS and chilling injury. The gene induction mechanism has been investigated extensively in the model crop Arabidopsis and several winter kinds of cereal. The ICE1 (inducer of C-repeat binding factor expression 1) and the CBF (C-repeat binding factor) transcriptional cascade are involved in transcriptional control. The functions of various CBFs and aquaporin genes were well studied in crop plants and their role in multiple stresses including cold stresses is deciphered. In addition, tissue nutrients and plant growth regulators like ABA, ethylene, jasmonic acid etc., also play a significant role in alleviating the LTS and chilling injury in fruit crops. However, these physiological, biochemical and molecular understanding of LTS tolerance/resistance are restricted to few of the temperate and tropical fruit crops. Therefore, a better understanding of cold tolerance's underlying physio-biochemical and molecular components in fruit crops is required under open and simulated LTS. The understanding of LTS tolerance/resistance mechanism will lay the foundation for tailoring the novel fruit genotypes for successful crop production under erratic weather conditions.

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