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1.
Nature ; 620(7974): 651-659, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37468627

RESUMEN

Even among genetically identical cancer cells, resistance to therapy frequently emerges from a small subset of those cells1-7. Molecular differences in rare individual cells in the initial population enable certain cells to become resistant to therapy7-9; however, comparatively little is known about the variability in the resistance outcomes. Here we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing, to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically and functionally distinct resistant types. These resistant types are largely predetermined by molecular differences between cells before drug addition and not by extrinsic factors. Changes in the dose and type of drug can switch the resistant type of an initial cell, resulting in the generation and elimination of certain resistant types. Samples from patients show evidence for the existence of these resistant types in a clinical context. We observed diversity in resistant types across several single-cell-derived cancer cell lines and cell types treated with a variety of drugs. The diversity of resistant types as a result of the variability in intrinsic cell states may be a generic feature of responses to external cues.


Asunto(s)
Antineoplásicos , Células Clonales , Resistencia a Antineoplásicos , Neoplasias , Humanos , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Células Clonales/patología , Código de Barras del ADN Taxonómico , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , RNA-Seq , Análisis de Expresión Génica de una Sola Célula , Células Tumorales Cultivadas , Antineoplásicos/farmacología
2.
Mol Cell ; 77(4): 683-685, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-32084350

RESUMEN

In the current issue of Molecular Cell, Liu et al. (2020) show that the secretion of cancer-linked forms of mutant calreticulin allow cancer cells to escape protective immune responses induced by chemotherapeutic and immunotherapeutic drugs, thereby promoting tumor growth.


Asunto(s)
Calreticulina , Neoplasias , Humanos , Fagocitosis
3.
Mol Cell ; 77(3): 633-644.e5, 2020 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-31836388

RESUMEN

Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.


Asunto(s)
Melanoma/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína Wnt-5a/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Humanos , Quinasas Quinasa Quinasa PAM/metabolismo , Melanoma/genética , Melanoma/patología , Terapia Molecular Dirigida , Mutación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología , Microambiente Tumoral/efectos de los fármacos , Proteína p53 Supresora de Tumor/fisiología
4.
Plant J ; 118(6): 2169-2187, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558472

RESUMEN

Genome-wide association studies (GWAS) are an effective approach to identify new specialized metabolites and the genes involved in their biosynthesis and regulation. In this study, GWAS of Arabidopsis thaliana soluble leaf and stem metabolites identified alleles of an uncharacterized BAHD-family acyltransferase (AT5G57840) associated with natural variation in three structurally related metabolites. These metabolites were esters of glucuronosylglycerol, with one metabolite containing phenylacetic acid as the acyl component of the ester. Knockout and overexpression of AT5G57840 in Arabidopsis and heterologous overexpression in Nicotiana benthamiana and Escherichia coli demonstrated that it is capable of utilizing phenylacetyl-CoA as an acyl donor and glucuronosylglycerol as an acyl acceptor. We, thus, named the protein Glucuronosylglycerol Ester Synthase (GGES). Additionally, phenylacetyl glucuronosylglycerol increased in Arabidopsis CYP79A2 mutants that overproduce phenylacetic acid and was lost in knockout mutants of UDP-sulfoquinovosyl: diacylglycerol sulfoquinovosyl transferase, an enzyme required for glucuronosylglycerol biosynthesis and associated with glycerolipid metabolism under phosphate-starvation stress. GGES is a member of a well-supported clade of BAHD family acyltransferases that arose by duplication and neofunctionalized during the evolution of the Brassicales within a larger clade that includes HCT as well as enzymes that synthesize other plant-specialized metabolites. Together, this work extends our understanding of the catalytic diversity of BAHD acyltransferases and uncovers a pathway that involves contributions from both phenylalanine and lipid metabolism.


Asunto(s)
Aciltransferasas , Arabidopsis , Fenilacetatos , Aciltransferasas/genética , Aciltransferasas/metabolismo , Arabidopsis/genética , Arabidopsis/enzimología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estudio de Asociación del Genoma Completo , Fenilacetatos/metabolismo
5.
Nat Methods ; 19(11): 1403-1410, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36280724

RESUMEN

RNA labeling in situ has enormous potential to visualize transcripts and quantify their levels in single cells, but it remains challenging to produce high levels of signal while also enabling multiplexed detection of multiple RNA species simultaneously. Here, we describe clampFISH 2.0, a method that uses an inverted padlock design to efficiently detect many RNA species and exponentially amplify their signals at once, while also reducing the time and cost compared with the prior clampFISH method. We leverage the increased throughput afforded by multiplexed signal amplification and sequential detection to detect 10 different RNA species in more than 1 million cells. We also show that clampFISH 2.0 works in tissue sections. We expect that the advantages offered by clampFISH 2.0 will enable many applications in spatial transcriptomics.


Asunto(s)
ARN , Transcriptoma , ARN/genética
6.
Plant Physiol ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709680

RESUMEN

Brassinosteroids (BR) and gibberellins (GA) regulate plant height and leaf angle in maize (Zea mays). Mutants with defects in BR or GA biosynthesis or signaling identify components of these pathways and enhance our knowledge about plant growth and development. In this study, we characterized three recessive mutant alleles of GRAS transcription factor 42 (gras42) in maize, a GRAS transcription factor gene orthologous to the DWARF AND LOW TILLERING (DLT) gene of rice (Oryza sativa). These maize mutants exhibited semi-dwarf stature, shorter and wider leaves, and more upright leaf angle. Transcriptome analysis revealed a role for GRAS42 as a determinant of BR signaling. Analysis of the expression consequences from loss of GRAS42 in the gras42-mu1021149 mutant indicated a weak loss of BR signaling in the mutant, consistent with its previously demonstrated role in BR signaling in rice. Loss of BR signaling was also evident by the enhancement of weak BR biosynthetic mutant alleles in double mutants of nana plant1-1 and gras42-mu1021149. The gras42-mu1021149 mutant had little effect on GA-regulated gene expression, suggesting that GRAS42 is not a regulator of core GA signaling genes in maize. Single cell expression data identified gras42 expressed among cells in the G2/M phase of the cell cycle consistent with its previously demonstrated role in cell cycle gene expression in Arabidopsis (Arabidopsis thaliana). Cis-acting natural variation controlling GRAS42 transcript accumulation was identified by expression genome-wide association study (eGWAS) in maize. Our results demonstrate a conserved role for GRAS42/SCARECROW-LIKE 28 (SCL28)/DLT in BR signaling, clarify the role of this gene in GA signaling, and suggest mechanisms of tillering and leaf angle control by BR.

7.
J Immunol ; 211(9): 1298-1307, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37737643

RESUMEN

The extreme polymorphisms of HLA class I proteins result in structural variations in their peptide binding sites to achieve diversity in Ag presentation. External factors could independently constrict or alter HLA class I peptide repertoires. Such effects of the assembly factor tapasin were assessed for HLA-B*44:05 (Y116) and a close variant, HLA-B*44:02 (D116), which have low and high tapasin dependence, respectively, for their cell surface expression. Analyses of the HLA-B*44:05 peptidomes in the presence and absence of tapasin reveal that peptides with C-terminal tryptophans and higher predicted affinities are preferentially selected by tapasin, coincident with reduced frequencies of peptides with other C-terminal amino acids, including leucine. Comparisons of the HLA-B*44:05 and HLA-B*44:02 peptidomes indicate the expected structure-based alterations near the peptide C termini, but also C-terminal amino acid frequency and predicted affinity changes among the unique and shared peptide groups for B*44:02 and B*44:05. Overall, these findings indicate that the presence of tapasin and the tapasin dependence of assembly alter HLA class I peptide-binding preferences at the peptide C terminus. The particular C-terminal amino acid preferences that are altered by tapasin are expected to be determined by the intrinsic peptide-binding specificities of HLA class I allotypes. Additionally, the findings suggest that tapasin deficiency and reduced tapasin dependence expand the permissive affinities of HLA class I-bound peptides, consistent with prior findings that HLA class I allotypes with low tapasin dependence have increased breadth of CD8+ T cell epitope presentation and are more protective in HIV infections.


Asunto(s)
Infecciones por VIH , Triptófano , Humanos , Antígeno HLA-B44/metabolismo , Triptófano/metabolismo , Péptidos/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Inmunoglobulinas/metabolismo , Unión Proteica , Antígenos HLA-B/genética , Antígenos HLA-B/metabolismo
8.
Plant Physiol ; 192(2): 1016-1027, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-36905371

RESUMEN

The Arabidopsis (Arabidopsis thaliana) BYPASS1 (BPS1) gene encodes a protein with no functionally characterized domains, and loss-of-function mutants (e.g. bps1-2 in Col-0) present a severe growth arrest phenotype that is evoked by a root-derived graft-transmissible small molecule that we call dalekin. The root-to-shoot nature of dalekin signaling suggests it could be an endogenous signaling molecule. Here, we report a natural variant screen that allowed us to identify enhancers and suppressors of the bps1-2 mutant phenotype (in Col-0). We identified a strong semi-dominant suppressor in the Apost-1 accession that largely restored shoot development in bps1 and yet continued to overproduce dalekin. Using bulked segregant analysis and allele-specific transgenic complementation, we showed that the suppressor is the Apost-1 allele of a BPS1 paralog, BYPASS2 (BPS2). BPS2 is one of four members of the BPS gene family in Arabidopsis, and phylogenetic analysis demonstrated that the BPS family is conserved in land plants and the four Arabidopsis paralogs are retained duplicates from whole genome duplications. The strong conservation of BPS1 and paralogous proteins throughout land plants, and the similar functions of paralogs in Arabidopsis, suggests that dalekin signaling might be retained across land plants.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Alelos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fenotipo , Filogenia , Raíces de Plantas/metabolismo
9.
BMC Cancer ; 24(1): 482, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627648

RESUMEN

BACKGROUND: Therapies for metastatic castration-resistant prostate cancer (mCRPC) include targeting the androgen receptor (AR) with androgen receptor inhibitors (ARIs) and prostate-specific membrane antigen (PSMA). Having the ability to detect AR, AR splice variant 7 (AR-V7), or PSMA in circulating tumor cells (CTCs) or circulating exosomal cell-free RNA (cfRNA) could be helpful to guide selection of the appropriate therapy for each individual patient. The Vortex Biosciences VTX-1 system is a label-free CTC isolation system that enables the detection of the expression of multiple genes in both CTCs and exosomal cfRNA from the same blood sample in patients with mCRPC. Detection of both AR-V7 and PSMA gene expression in both CTCs and cfRNA simultaneously has not yet been reported. METHODS: To characterize the combined VTX-1-AdnaDetect workflow, 22Rv1 cancer cells were spiked into blood from healthy donors and processed with the VTX-1 to mimic patient samples and assess performances (capture efficiency, purity, AR and AR-V7 expression). Then, we collected 19 blood samples from 16 patients with mCRPC and therapeutic resistance to androgen receptor inhibitors (ARIs). Plasma was separated and the plasma-depleted blood was processed further with the VTX-1 to collect CTCs. Both plasma exosomal cfRNA and CTCs were subsequently analyzed for AR, AR-V7, PSMA, and prostate-specific antigen (PSA) mRNA expression using the AdnaTest ProstateCancerPanel AR-V7 assay. RESULTS: AR-V7 expression could be detected in 22Rv1 cells spiked into blood from healthy volunteers as well as in CTCs and plasma-derived exosomal cfRNA from patients with mCRPC by processing blood with the VTX-1 CTC isolation system followed by the AdnaTest ProstateCancerPanel AR-V7 assay. 94.7% of patient blood samples (18/19) had detectable AR expression in either CTCs or exosomal cfRNA (16 in CTCs, 12 in cfRNA). 15.8% of the 19 patient blood samples (3/19) were found to have AR-V7-positive (AR-V7+) CTCs, one of which was also AR-V7+ in the exosomal cfRNA analysis. 42.1% of patient blood samples (8/19) were found to be PSMA positive (PSMA+): 26.3% (5/19) were PSMA+ in the CTC analysis and 31.6% (6/19) were PSMA+ in the exosomal cfRNA analysis. Of those 8 PSMA+ samples, 2 had detectable PSMA only in CTCs, and 3 had detectable PSMA only in exosomal cfRNA. CONCLUSION: VTX-1 enables isolation of CTCs and plasma exosomes from a single blood draw and can be used for detecting AR-V7 and PSMA mRNA in both CTCs and cfRNA in patients with mCRPC and resistance to ARIs. This technology facilitates combining RNA measurements in CTCs and exosomal cfRNA for future studies to develop potentially clinically relevant cancer biomarker detection in blood.


Asunto(s)
Ácidos Nucleicos Libres de Células , Exosomas , Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Antagonistas de Receptores Androgénicos/farmacología , Antagonistas de Receptores Androgénicos/uso terapéutico , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Ácidos Nucleicos Libres de Células/metabolismo , Exosomas/genética , Exosomas/metabolismo , Células Neoplásicas Circulantes/patología , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Isoformas de Proteínas/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , ARN Mensajero/genética
10.
Appl Microbiol Biotechnol ; 108(1): 247, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427084

RESUMEN

Host and tissue-specificity of endophytes are important attributes that limit the endophyte application on multiple crops. Therefore, understanding the endophytic composition of the targeted crop is essential, especially for the dioecious plants where the male and female plants are different. Here, efforts were made to understand the endophytic bacterial composition of the dioecious Siraitia grosvenorii plant using 16S rRNA amplicon sequencing. The present study revealed the association of distinct endophytic bacterial communities with different parts of male and female plants. Roots of male and female plants had a higher bacterial diversity than other parts of plants, and the roots of male plants had more bacterial diversity than the roots of female plants. Endophytes belonging to the phylum Proteobacteria were abundant in all parts of male and female plants except male stems and fruit pulp, where the Firmicutes were most abundant. Class Gammaproteobacteria predominated in both male and female plants, with the genus Acinetobacter as the most dominant and part of the core microbiome of the plant (present in all parts of both, male and female plants). The presence of distinct taxa specific to male and female plants was also identified. Macrococcus, Facklamia, and Propionibacterium were the distinct genera found only in fruit pulp, the edible part of S. grosvenorii. Predictive functional analysis revealed the abundance of enzymes of secondary metabolite (especially mogroside) biosynthesis in the associated endophytic community with predominance in roots. The present study revealed bacterial endophytic communities of male and female S. grosvenorii plants that can be further explored for monk fruit cultivation, mogroside production, and early-stage identification of male and female plants. KEY POINTS: • Male and female Siraitia grosvenorii plants had distinct endophytic communities • The diversity of endophytic communities was specific to different parts of plants • S. grosvenorii-associated endophytes may be valuable for mogroside biosynthesis and monk fruit cultivation.


Asunto(s)
Microbiota , ARN Ribosómico 16S/genética , Bacterias/genética , Firmicutes/genética , Endófitos/genética , Productos Agrícolas/genética
11.
J Cell Mol Med ; 27(8): 1032-1044, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36916035

RESUMEN

Myeloproliferative neoplasms (MPNs) are cancers involving dysregulated production and function of myeloid lineage hematopoietic cells. Among MPNs, Essential thrombocythemia (ET), Polycythemia Vera (PV) and Myelofibrosis (MF), are driven by mutations that activate the JAK-STAT signalling pathway. Somatic mutations of calreticulin (CRT), an endoplasmic reticulum (ER)-localized lectin chaperone, are driver mutations in approximately 25% of ET and 35% of MF patients. The MPN-linked mutant CRT proteins have novel frameshifted carboxy-domain sequences and lack an ER retention motif, resulting in their secretion. Wild type CRT is a regulator of ER calcium homeostasis and plays a key role in the assembly of major histocompatibility complex (MHC) class I molecules, which are the ligands for antigen receptors of CD8+ T cells. Mutant CRT-linked oncogenesis results from the dysregulation of calcium signalling in cells and the formation of stable complexes of mutant CRT with myeloproliferative leukemia (MPL) protein, followed by downstream activation of the JAK-STAT signalling pathway. The intricate participation of CRT in ER protein folding, calcium homeostasis and immunity suggests the involvement of multiple mechanisms of mutant CRT-linked oncogenesis. In this review, we highlight recent findings related to the role of MPN-linked CRT mutations in the dysregulation of calcium homeostasis, MPL activation and immunity.


Asunto(s)
Calreticulina , Trastornos Mieloproliferativos , Humanos , Calcio/metabolismo , Calreticulina/genética , Calreticulina/metabolismo , Carcinogénesis , Linfocitos T CD8-positivos/metabolismo , Transformación Celular Neoplásica , Janus Quinasa 2/metabolismo , Mutación , Trastornos Mieloproliferativos/genética
13.
Pharm Dev Technol ; 28(6): 547-558, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37256734

RESUMEN

The aim of this study is to prepare and characterise mucoadhesive silica-coated silver nanoparticles loaded with ciprofloxacin (S-AgNPs-CSCFX), and investigate serum biochemical, haematological, and histopathological effects in Sprague Dawley rats upon oral administration. S-AgNPs-CSCFX microparticles were prepared using three fluid nozzle spray drying and characterised by scanning electron microscopy (SEM), X-ray dispersive spectrometry (EDX), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), zeta potential and particles size measurements and X-ray powder diffraction (XRPD). Adult male Sprague Dawley rats were randomly divided between six-treated groups, including blank S-AgNPs and S-AgNPs-CSCFX (LD: Low dose; MD: Median Dose; HD: High Dose) and control group. Each group was treated daily to evaluate the effect of the prepared particles on the lipid profile, serum biochemical, hormonal level, haemogram, and vital organ histopathology. The results showed successful encapsulation of silver nanoparticles which resulted in spherical-shaped S-AgNPs-CSCFX with an average size of 1-5 µm and surface charge of 25.2 ± 5.52 mv. The in-vivo results showed that different doses of blank S-AgNPs and S-AgNPs-CSCFX had no significant toxic effects on the physiological, biochemical, and haematological parameters. There were no marked histopathological alterations in the vital organs of the treated rats with blank and loaded particles.


Asunto(s)
Nanopartículas del Metal , Masculino , Ratas , Animales , Ratas Sprague-Dawley , Plata , Administración Oral , Ciprofloxacina , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Extractos Vegetales , Antibacterianos
14.
Electromagn Biol Med ; 42(4): 163-181, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-38156657

RESUMEN

This research article presents a study that uses microwave frequencies (ISM band) for treatment of skin cancer by heating the malignant cells on skin with a Microwave Hyperthermia (MWHT) applicator. The proposed MWHT applicator has been designed as an Archimedean Spiral Microstrip Patch Antenna (AMSPA) of dimensions 38 × 38 × 1.64 mm3 backed with a Meshed-shaped AMC (48 × 48 × 3.27mm3) reflector, placed at an optimized distance of 12 mm from AMSPA. The proposed AMSPA is designed as a single spiral resonator and fabricated on FR-4 substrate, excited using a feed network. The proposed AMSPA shows a resonance at 2.5 GHz with an impedance BW of 260 MHz (2.37-2.63 GHz) and peak gain of 3.20 dB with a bidirectional radiation pattern. An AMC is placed at its backside that can be exploited as a phase-compensation surface to attain an in-phase profile for directive emission and improve the BW upto 470 MHz, peak gain to 6.8 dB and also enhance the front-to-back ratio of the radiating antenna with radiation efficiency of 80%. The simulated environment for hyperthermia analysis is set up using penne's Bio-Heat equations to deliver microwave energy to the bio-mimic, that leads to a rise in temperature over the designed bio-mimic in CST MWS in the range of 41-45°C. The validation of MWHT radiation properties and temperature rise inside the malignancy of phantom is carried out by fabricating the bio-mimic using gelatine, vegetable oils and glycerol. This set up enhances the penetration-depth of EM waves inside the tri-layered phantom up-to 29.5 mm with Effective Field Surface of 36 × 36 mm2 and SAR of 8 W/Kg.


This article discusses the design and development of a device designed to treat skin cancer, specifically melanoma. This device is called a Microwave Hyperthermia (MWHT) applicator. The applicator sends out focused waves of microwave energy but at a specific frequency of ISM band. These waves heat up a model of human skin, simulating what would happen if this is used on a real person with cancer. The goal is to heat the cancer to around 45°C, which can help treat it. The special thing about this applicator is that it's designed to be very compact and have good gain. It heats up the cancer without causing harm to the healthy tissues nearby. The researchers tested it extensively and found that it works well. It has a wide range of effectiveness for different tumor sizes and depths within the skin. To make sure it is safe and accurate, a model of a human forearm using materials like gelatin and water has been prepared. Then used the applicator on this model and measured the temperature increase. After about 40 minutes of exposure, there is a temperature rise of about 45 degrees Celsius. Thus this article is about a device that uses special waves to heat up and treat skin cancer. It's designed to be safe and effective, and the tests show it works on a model of human skin. This could be a useful tool for treating skin cancer in the future.


Asunto(s)
Hipertermia Inducida , Neoplasias Cutáneas , Humanos , Hipertermia Inducida/métodos , Microondas , Neoplasias Cutáneas/terapia , Temperatura , Calor
15.
Mol Pharm ; 19(3): 985-997, 2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-35188397

RESUMEN

The study investigated the milling behavior of voriconazole (VRZ) subjected to particle size reduction using air jet mill at differential air pressures of 5, 6, 7, and 8 bar for five cycles at each pressure. The crystal structure of VRZ was probed for understanding the fracture behavior from crystal packing and intermolecular interactions using molecular modeling tools of attachment energy (Eatt), density functional theory, and energy framework analysis. Upon milling for different cycles, VRZ showed that size reduction from (D90) 20 to 9 µm and 100% particles could not be milled to sizes below 9 µm, with the increase in either the milling intensity or cycle. The milled samples retained the original crystal lattice as evident from consistent melting endotherm (Tm = 130.75 °C); heat of fusion (ΔHf = 96.52 J/g) values; and the plate-shaped morphology. The powder X-ray diffraction pattern of milled samples consistently showed characteristic peaks of stable form B of VRZ. The crystallographic plane (001) was found to be the most prominent slip and the cleavage plane due to least Eatt and weak noncovalent interactions (6.996 kJ/mol) between 3'H and 4'F functional groups of the neighboring planes. The predicted indentation hardness value of 228.67 MPa further indicated toward the plastic nature of VRZ crystals. Corroborating outcomes from the different molecular modeling tools for VRZ, cleavage along the plane (001) was determined to be energetically favorable, whereas cleavage of isotropic 2D molecular sheets was energetically unfavorable. As milling proceeds and crystal reduces in size, contact surface area and overall interaction energy decrease contributing to plastic behavior of the crystal. It was concluded that crystal plasticity and isotropic 2D molecular sheets along with the orientation of particles to the direction of stress and attrition energy during air jet milling are contributing factors for nonuniform size reduction of VRZ particles.


Asunto(s)
Plásticos , Tamaño de la Partícula , Polvos , Voriconazol , Difracción de Rayos X
16.
Nature ; 532(7598): 250-4, 2016 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-27042933

RESUMEN

Cancer is a disease of ageing. Clinically, aged cancer patients tend to have a poorer prognosis than young. This may be due to accumulated cellular damage, decreases in adaptive immunity, and chronic inflammation. However, the effects of the aged microenvironment on tumour progression have been largely unexplored. Since dermal fibroblasts can have profound impacts on melanoma progression, we examined whether age-related changes in dermal fibroblasts could drive melanoma metastasis and response to targeted therapy. Here we find that aged fibroblasts secrete a Wnt antagonist, sFRP2, which activates a multi-step signalling cascade in melanoma cells that results in a decrease in ß-catenin and microphthalmia-associated transcription factor (MITF), and ultimately the loss of a key redox effector, APE1. Loss of APE1 attenuates the response of melanoma cells to DNA damage induced by reactive oxygen species, rendering the cells more resistant to targeted therapy (vemurafenib). Age-related increases in sFRP2 also augment both angiogenesis and metastasis of melanoma cells. These data provide an integrated view of how fibroblasts in the aged microenvironment contribute to tumour progression, offering new possibilities for the design of therapy for the elderly.


Asunto(s)
Envejecimiento/metabolismo , Resistencia a Antineoplásicos , Melanoma/tratamiento farmacológico , Melanoma/patología , Proteínas de la Membrana/metabolismo , Metástasis de la Neoplasia , Microambiente Tumoral , Adulto , Animales , Línea Celular Tumoral , Medios de Cultivo Condicionados/farmacología , Daño del ADN , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Progresión de la Enfermedad , Fibroblastos/metabolismo , Humanos , Indoles/farmacología , Indoles/uso terapéutico , Masculino , Melanoma/irrigación sanguínea , Melanoma/genética , Ratones , Factor de Transcripción Asociado a Microftalmía/metabolismo , Persona de Mediana Edad , Terapia Molecular Dirigida , Neovascularización Patológica , Estrés Oxidativo , Fenotipo , Especies Reactivas de Oxígeno/metabolismo , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Vemurafenib , Vía de Señalización Wnt , Proteína Wnt1/antagonistas & inhibidores , beta Catenina/metabolismo
17.
J Obstet Gynaecol Can ; 44(8): 895-900, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35513257

RESUMEN

OBJECTIVE: The effect of expanded obstetrical ultrasound cardiac views on the diagnosis of fetal congenital heart disease (CHD) has not been fully examined at a population level. We hypothesized there has been a significant increase in the prenatal detection of CHD in Alberta, particularly for CHD associated with cardiac outflow tract and 3-vessel view abnormalities. METHODS: Using provincial databases, we retrospectively identified all fetuses and infants diagnosed between 2008 and 2018 in Alberta with major CHD requiring surgical intervention within the first postnatal year. We evaluated individual lesions and categorized CHDs into the following groups based on the obstetrical ultrasound cardiac views required for detection: (1) 4-chamber view (e.g., hypoplastic left heart syndrome, Ebstein's anomaly, single ventricle); (2) outflow tract view (e.g., tetralogy of Fallot, d-transposition, truncus arteriosus); (3) 3-vessel or other non-standard cardiac views (e.g., coarctation, anomalous pulmonary veins); and (4) isolated ventricular septal defects using any view. RESULTS: Of 1405 cases of major CHD, 814 (58%) were prenatally diagnosed. Over the study period, prenatal detection increased in all groups, with the greatest increase observed for groups 1 and 2 (75%-88%; P = 0.008 and 56%-79%; P = 0.0002, respectively). Although rates of prenatal detection also increased for groups 3 and 4 (27%-43%; P = 0.007 and 13%-30%; P = 0.04, respectively), fewer than half of the cases in each group were detected prenatally, even in more recent years. CONCLUSIONS: While rates of prenatal detection of CHD have significantly improved during the past decade, many defects with abnormal 3-vessel and non-standard views, as well as isolated ventricular septal defects, still go undetected.


Asunto(s)
Enfermedades Fetales , Cardiopatías Congénitas , Defectos del Tabique Interventricular , Alberta/epidemiología , Femenino , Enfermedades Fetales/epidemiología , Corazón Fetal/anomalías , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/epidemiología , Humanos , Lactante , Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal
18.
Sensors (Basel) ; 22(21)2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36365871

RESUMEN

In today's scenario, blockchain technology is an emerging area and promising technology in the field of the food supply chain industry (FSCI). A literature survey comprising an analytical review of blockchain technology with the Internet of things (IoT) for food supply chain management (FSCM) is presented to better understand the associated research benefits, issues, and challenges. At present, with the concept of farm-to-fork gaining increasing popularity, food safety and quality certification are of critical concern. Blockchain technology provides the traceability of food supply from the source, i.e., the seeding factories, to the customer's table. The main idea of this paper is to identify blockchain technology with the Internet of things (IoT) devices to investigate the food conditions and various issues faced by transporters while supplying fresh food. Blockchain provides applications such as smart contracts to monitor, observe, and manage all transactions and communications among stakeholders. IoT technology provides approaches for verifying all transactions; these transactions are recorded and then stored in a centralized database system. Thus, IoT enables a safe and cost-effective FSCM system for stakeholders. In this paper, we contribute to the awareness of blockchain applications that are relevant to the food supply chain (FSC), and we present an analysis of the literature on relevant blockchain applications which has been conducted concerning various parameters. The observations in the present survey are also relevant to the application of blockchain technology with IoT in other areas.


Asunto(s)
Cadena de Bloques , Internet de las Cosas , Abastecimiento de Alimentos , Monitoreo Fisiológico , Tecnología
19.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35409240

RESUMEN

The activity of the epithelial Na+ Channel (ENaC) is strongly dependent on the membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2). PIP2 binds two distinct cationic clusters within the N termini of ß- and γ-ENaC subunits (ßN1 and γN2). The affinities of these sites were previously determined using short synthetic peptides, yet their role in sensitizing ENaC to changes in PIP2 levels in the cellular system is not well established. We addressed this question by comparing the effects of PIP2 depletion and recovery on ENaC channel activity and intracellular Na+ levels [Na+]i. We tested effects on ENaC activity with mutations to the PIP2 binding sites using the optogenetic system CIBN/CRY2-OCRL to selectively deplete PIP2. We monitored changes of [Na+]i by measuring the fluorescent Na+ indicator, CoroNa Green AM, and changes in channel activity by performing patch clamp electrophysiology. Whole cell patch clamp measurements showed a complete lack of response to PIP2 depletion and recovery in ENaC with mutations to ßN1 or γN2 or both sites, compared to wild type ENaC. Whereas mutant ßN1 also had no change in CoroNa Green fluorescence in response to PIP2 depletion, γN2 did have reduced [Na+]i, which was explained by having shorter CoroNa Green uptake and half-life. These results suggest that CoroNa Green measurements should be interpreted with caution. Importantly, the electrophysiology results show that the ßN1 and γN2 sites on ENaC are each necessary to permit maximal ENaC activity in the presence of PIP2.


Asunto(s)
Canales Epiteliales de Sodio , Fosfatidilinositol 4,5-Difosfato , Sitios de Unión , Canales Epiteliales de Sodio/metabolismo , Optogenética , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfatidilinositoles/metabolismo , Sodio/metabolismo
20.
Indian J Palliat Care ; 28(1): 37-42, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35673384

RESUMEN

Objectives: Increased levels of psychological distress and burnout in cancer palliative care professionals have implications on their psychological well-being, quality of patient care they provide and for their employing organisations. There is a dearth of studies on psychological well-being with no published study available on psychological well-being amongst cancer palliative care professionals in India. The aim of the present study was to assess psychological well-being amongst cancer palliative care professionals. Materials and Methods: The study was cross-sectional and quantitative which was carried out at four cancer palliative care centers (one hospice and three hospitals) in Bengaluru city of India. The tools sociodemographic and professional datasheet and psychological well-being (PWB-20) scale were administered with 65 participants (Mean Age = 32.5, SD = 11.78). Purposive sampling method was used to recruit the participants working full-time at respective centers after obtaining permissions and ethical approvals. Descriptive, correlational, and inferential analysis of the quantitative data was carried out based on normality of the distribution. Results: The results revealed above average levels of self-acceptance and engagement and growth, below average levels of mastery and competence, while average levels of positive relations and PWB (total score). Significant differences in PWB domains based on age (P < 0.05) and self-care practices (P < 0.05) were seen. Sense of engagement and growth was found to be positively correlated with age and income earned per month (P = 0.01). Conclusion: Findings from the present study suggest that cancer palliative care professionals had moderate levels of PWB with implications in training and future research.

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