Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.064
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 120(41): e2305327120, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37788308

RESUMO

Heavy-metal-free III-V colloidal quantum dots (CQDs) show promise in optoelectronics: Recent advancements in the synthesis of large-diameter indium arsenide (InAs) CQDs provide access to short-wave infrared (IR) wavelengths for three-dimensional ranging and imaging. In early studies, however, we were unable to achieve a rectifying photodiode using CQDs and molybdenum oxide/polymer hole transport layers, as the shallow valence bandedge (5.0 eV) was misaligned with the ionization potentials of the widely used transport layers. This occurred when increasing CQD diameter to decrease the bandgap below 1.1 eV. Here, we develop a rectifying junction among InAs CQD layers, where we use molecular surface modifiers to tune the energy levels of InAs CQDs electrostatically. Previously developed bifunctional dithiol ligands, established for II-VI and IV-VI CQDs, exhibit slow reaction kinetics with III-V surfaces, causing the exchange to fail. We study carboxylate and thiolate binding groups, united with electron-donating free end groups, that shift upward the valence bandedge of InAs CQDs, producing valence band energies as shallow as 4.8 eV. Photophysical studies combined with density functional theory show that carboxylate-based passivants participate in strong bidentate bridging with both In and As on the CQD surface. The tuned CQD layer incorporated into a photodiode structure achieves improved performance with EQE (external quantum efficiency) of 35% (>1 µm) and dark current density < 400 nA cm-2, a >25% increase in EQE and >90% reduced dark current density compared to the reference device. This work represents an advance over previous III-V CQD short-wavelength IR photodetectors (EQE < 5%, dark current > 10,000 nA cm-2).

2.
Cancer Metastasis Rev ; 43(1): 409-421, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37950087

RESUMO

MYB transcription factors are encoded by a large family of highly conserved genes from plants to vertebrates. There are three members of the MYB gene family in human, namely, MYB, MYBL1, and MYBL2 that encode MYB/c-MYB, MYBL1/A-MYB, and MYBL2/B-MYB, respectively. MYB was the first member to be identified as a cellular homolog of the v-myb oncogene carried by the avian myeloblastosis virus (AMV) causing leukemia in chickens. Under the normal scenario, MYB is predominantly expressed in hematopoietic tissues, colonic crypts, and neural stem cells and plays a role in maintaining the undifferentiated state of the cells. Over the years, aberrant expression of MYB genes has been reported in several malignancies and recent years have witnessed tremendous progress in understanding of their roles in processes associated with cancer development. Here, we review various MYB alterations reported in cancer along with the roles of MYB family proteins in tumor cell plasticity, therapy resistance, and other hallmarks of cancer. We also discuss studies that provide mechanistic insights into the oncogenic functions of MYB transcription factors to identify potential therapeutic vulnerabilities.


Assuntos
Neoplasias , Fatores de Transcrição , Animais , Humanos , Plasticidade Celular/genética , Galinhas , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/genética , Fatores de Transcrição/genética
3.
EMBO Rep ; 24(3): e55643, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36592158

RESUMO

Extensive desmoplasia and poor vasculature renders pancreatic tumors severely hypoxic, contributing to their aggressiveness and therapy resistance. Here, we identify the HuR/MYB/HIF1α axis as a critical regulator of the metabolic plasticity and hypoxic survival of pancreatic cancer cells. HuR undergoes nuclear-to-cytoplasmic translocation under hypoxia and stabilizes MYB transcripts, while MYB transcriptionally upregulates HIF1α. Upon MYB silencing, pancreatic cancer cells fail to survive and adapt metabolically under hypoxia, despite forced overexpression of HIF1α. MYB induces the transcription of several HIF1α-regulated glycolytic genes by directly binding to their promoters, thus enhancing the recruitment of HIF1α to hypoxia-responsive elements through its interaction with p300-dependent histone acetylation. MYB-depleted pancreatic cancer cells exhibit a dramatic reduction in tumorigenic ability, glucose-uptake and metabolism in orthotopic mouse model, even after HIF1α restoration. Together, our findings reveal an essential role of MYB in metabolic reprogramming that supports pancreatic cancer cell survival under hypoxia.


Assuntos
Neoplasias Pancreáticas , Camundongos , Animais , Neoplasias Pancreáticas/genética , Hipóxia , Regiões Promotoras Genéticas , Hipóxia Celular/genética , Linhagem Celular Tumoral , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
4.
J Biol Chem ; 299(1): 102725, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410437

RESUMO

MYB, a proto-oncogene, is overexpressed in prostate cancer (PCa) and promotes its growth, aggressiveness, and resistance to androgen-deprivation therapy. Here, we examined the effect of androgen signaling on MYB expression and delineated the underlying molecular mechanisms. Paralleling a dichotomous effect on growth, low-dose androgen induced MYB expression at both transcript and protein levels, whereas it was suppressed in high-dose androgen-treated PCa cells. Interestingly, treatment with both low- and high-dose androgen transcriptionally upregulated MYB by increasing the binding of androgen receptor to the MYB promoter. In a time-course assay, androgen induced MYB expression at early time points followed by a sharp decline in high-dose androgen-treated cells due to decreased stability of MYB mRNA. Additionally, profiling of MYB-targeted miRNAs demonstrated significant induction of miR-150 in high-dose androgen-treated PCa cells. We observed a differential binding of androgen receptor on miR-150 promoter with significantly greater occupancy recorded in high-dose androgen-treated cells than those treated with low-dose androgen. Functional inhibition of miR-150 relieved MYB suppression by high-dose androgen, while miR-150 mimic abolished MYB induction by low-dose androgen. Furthermore, MYB-silencing or miR-150 mimic transfection suppressed PCa cell growth induced by low-dose androgen, whereas miR-150 inhibition rescued PCa cells from growth repression by high-dose androgen. Similarly, we observed that MYB silencing suppressed the expression of androgen-responsive, cell cycle-related genes in low-dose androgen-treated cells, while miR-150 inhibition increased their expression in cells treated with high-dose androgen. Overall, these findings reveal novel androgen-mediated mechanisms of MYB regulation that support its biphasic growth control in PCa cells.


Assuntos
Androgênios , MicroRNAs , Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-myb , Humanos , Masculino , Antagonistas de Androgênios , Androgênios/farmacologia , Androgênios/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Proto-Oncogênicas c-myb/genética , Proteínas Proto-Oncogênicas c-myb/metabolismo , Processamento de Proteína Pós-Traducional , Células Tumorais Cultivadas
5.
N Engl J Med ; 385(25): 2325-2335, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34739194

RESUMO

BACKGROUND: Among patients with chronic kidney disease (CKD), the use of recombinant human erythropoietin and its derivatives for the treatment of anemia has been linked to a possibly increased risk of stroke, myocardial infarction, and other adverse events. Several trials have suggested that hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors (PHIs) are as effective as erythropoiesis-stimulating agents (ESAs) in increasing hemoglobin levels. METHODS: In this randomized, open-label, phase 3 trial, we assigned patients with CKD who were undergoing dialysis and who had a hemoglobin level of 8.0 to 11.5 g per deciliter to receive an oral HIF-PHI (daprodustat) or an injectable ESA (epoetin alfa if they were receiving hemodialysis or darbepoetin alfa if they were receiving peritoneal dialysis). The two primary outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52 (noninferiority margin, -0.75 g per deciliter) and the first occurrence of a major adverse cardiovascular event (a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke), with a noninferiority margin of 1.25. RESULTS: A total of 2964 patients underwent randomization. The mean (±SD) baseline hemoglobin level was 10.4±1.0 g per deciliter overall. The mean (±SE) change in the hemoglobin level from baseline to weeks 28 through 52 was 0.28±0.02 g per deciliter in the daprodustat group and 0.10±0.02 g per deciliter in the ESA group (difference, 0.18 g per deciliter; 95% confidence interval [CI], 0.12 to 0.24), which met the prespecified noninferiority margin of -0.75 g per deciliter. During a median follow-up of 2.5 years, a major adverse cardiovascular event occurred in 374 of 1487 patients (25.2%) in the daprodustat group and in 394 of 1477 (26.7%) in the ESA group (hazard ratio, 0.93; 95% CI, 0.81 to 1.07), which also met the prespecified noninferiority margin for daprodustat. The percentages of patients with other adverse events were similar in the two groups. CONCLUSIONS: Among patients with CKD undergoing dialysis, daprodustat was noninferior to ESAs regarding the change in the hemoglobin level from baseline and cardiovascular outcomes. (Funded by GlaxoSmithKline; ASCEND-D ClinicalTrials.gov number, NCT02879305.).


Assuntos
Anemia/tratamento farmacológico , Barbitúricos/uso terapêutico , Darbepoetina alfa/uso terapêutico , Epoetina alfa/uso terapêutico , Glicina/análogos & derivados , Hematínicos/uso terapêutico , Diálise Renal , Insuficiência Renal Crônica/complicações , Idoso , Anemia/etiologia , Barbitúricos/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Darbepoetina alfa/efeitos adversos , Epoetina alfa/efeitos adversos , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Hematínicos/efeitos adversos , Hemoglobinas/análise , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/terapia , Acidente Vascular Cerebral/epidemiologia
6.
N Engl J Med ; 385(25): 2313-2324, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34739196

RESUMO

BACKGROUND: Daprodustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor. In patients with chronic kidney disease (CKD) who are not undergoing dialysis, the efficacy and safety of daprodustat, as compared with the conventional erythropoiesis-stimulating agent darbepoetin alfa, are unknown. METHODS: In this randomized, open-label, phase 3 trial with blinded adjudication of cardiovascular outcomes, we compared daprodustat with darbepoetin alfa for the treatment of anemia in patients with CKD who were not undergoing dialysis. The primary outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52 and the first occurrence of a major adverse cardiovascular event (MACE; a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke). RESULTS: Overall, 3872 patients were randomly assigned to receive daprodustat or darbepoetin alfa. The mean (±SD) baseline hemoglobin levels were similar in the two groups. The mean (±SE) change in the hemoglobin level from baseline to weeks 28 through 52 was 0.74±0.02 g per deciliter in the daprodustat group and 0.66±0.02 g per deciliter in the darbepoetin alfa group (difference, 0.08 g per deciliter; 95% confidence interval [CI], 0.03 to 0.13), which met the prespecified noninferiority margin of -0.75 g per deciliter. During a median follow-up of 1.9 years, a first MACE occurred in 378 of 1937 patients (19.5%) in the daprodustat group and in 371 of 1935 patients (19.2%) in the darbepoetin alfa group (hazard ratio, 1.03; 95% CI, 0.89 to 1.19), which met the prespecified noninferiority margin of 1.25. The percentages of patients with adverse events were similar in the two groups. CONCLUSIONS: Among patients with CKD and anemia who were not undergoing dialysis, daprodustat was noninferior to darbepoetin alfa with respect to the change in the hemoglobin level from baseline and with respect to cardiovascular outcomes. (Funded by GlaxoSmithKline; ASCEND-ND ClinicalTrials.gov number, NCT02876835.).


Assuntos
Anemia/tratamento farmacológico , Barbitúricos/uso terapêutico , Darbepoetina alfa/uso terapêutico , Glicina/análogos & derivados , Hematínicos/uso terapêutico , Insuficiência Renal Crônica/complicações , Idoso , Anemia/etiologia , Barbitúricos/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Darbepoetina alfa/efeitos adversos , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Hematínicos/efeitos adversos , Hemoglobinas/análise , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Insuficiência Renal Crônica/sangue , Acidente Vascular Cerebral/epidemiologia
7.
BMC Plant Biol ; 24(1): 702, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054439

RESUMO

BACKGROUND: Climate change exacerbates abiotic stresses, which are expected to intensify their impact on crop plants. Drought, the most prevalent abiotic stress, significantly affects agricultural production worldwide. Improving eggplant varieties to withstand abiotic stress is vital due to rising drought from climate change. Despite the diversity of wild eggplant species that thrive under harsh conditions, the understanding of their drought tolerance mechanisms remains limited. In the present study, we used chlorophyll fluorescence (ChlaF) imaging, which reveals a plant's photosynthetic health, to investigate desiccation tolerance in eggplant and its wild relatives. Conventional fluorescence measurements lack spatial heterogeneity, whereas ChlaF imaging offers comprehensive insights into plant responses to environmental stresses. Hence, employing noninvasive imaging techniques is essential for understanding this heterogeneity. RESULTS: Desiccation significantly reduced the leaf tissue moisture content (TMC) across species. ChlaF and TMC displayed greater photosystem II (PSII) efficiency after 54 h of desiccation in S. macrocarpum, S. torvum, and S. indicum, with S. macrocarpum demonstrating superior efficiency due to sustained fluorescence. PSII functions declined gradually in S. macrocarpum and S. torvum, unlike those in other species, which exhibited abrupt declines after 54 h of desiccation. However, after 54 h, PSII efficiency remained above 50% of its initial quantum yield in S. macrocarpum at 35% leaf RWC (relative water content), while S. torvum and S. indicum displayed 50% decreases at 31% and 33% RWC, respectively. Conversely, the susceptible species S. gilo and S. sisymbriifolium exhibited a 50% reduction in PSII function at an early stage of 50% RWC, whereas in S. melongena, this reduction occurred at 40% RWC. CONCLUSION: Overall, our study revealed notably greater leaf desiccation tolerance, especially in S. macrocarpum, S. torvum, and S. indicum, attributed to sustained PSII efficiency at low TMC levels, indicating that these species are promising sources of drought tolerance.


Assuntos
Clorofila , Solanum melongena , Clorofila/metabolismo , Fluorescência , Solanum melongena/fisiologia , Solanum melongena/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Dessecação , Complexo de Proteína do Fotossistema II/metabolismo , Fotossíntese/fisiologia , Estresse Fisiológico , Secas , Desidratação , Especificidade da Espécie
8.
Magn Reson Med ; 91(3): 1087-1098, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946544

RESUMO

PURPOSE: The clinical diagnosis and classification of Alexander disease (AxD) relies in part on qualitative neuroimaging biomarkers; however, these biomarkers fail to distinguish and discriminate different subtypes of AxD, especially in the presence of overlap in clinical symptoms. To address this gap in knowledge, we applied neurite orientation dispersion and density imaging (NODDI) to an innovative CRISPR-Cas9 rat genetic model of AxD to gain quantitative insights into the neural substrates and brain microstructural changes seen in AxD and to potentially identify novel quantitative NODDI biomarkers of AxD. METHODS: Multi-shell DWI of age- and sex-matched AxD and wild-type Sprague Dawley rats (n = 6 per sex per genotype) was performed and DTI and NODDI measures calculated. A 3 × 2 × 2 analysis of variance model was used to determine the effect of genotype, biological sex, and laterality on quantitative measures of DTI and NODDI across regions of interest implicated in AxD. RESULTS: There is a significant effect of genotype in the amygdala, hippocampus, neocortex, and thalamus in measures of both DTI and NODDI brain microstructure. A genotype by biological sex interaction was identified in DTI and NODDI measures in the corpus callosum, hippocampus, and neocortex. CONCLUSION: We present the first application of NODDI to the study of AxD using a rat genetic model of AxD. Our analysis identifies alterations in NODDI and DTI measures to large white matter tracts and subcortical gray nuclei. We further identified genotype by sex interactions, suggesting a possible role for biological sex in the neuropathogenesis of AxD.


Assuntos
Doença de Alexander , Substância Branca , Ratos , Animais , Imagem de Tensor de Difusão/métodos , Doença de Alexander/patologia , Ratos Sprague-Dawley , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Branca/patologia , Biomarcadores , Imagem de Difusão por Ressonância Magnética
9.
Hum Genomics ; 17(1): 112, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38098073

RESUMO

BACKGROUND: Sudden sensorineural hearing loss (SSNHL) is an abrupt loss of hearing, still idiopathic in most of cases. Several mechanisms have been proposed including genetic and epigenetic interrelationships also considering iron homeostasis genes, ferroptosis and cellular stressors such as iron excess and dysfunctional mitochondrial superoxide dismutase activity. RESULTS: We investigated 206 SSNHL patients and 420 healthy controls for the following genetic variants in the iron pathway: SLC40A1 - 8CG (ferroportin; FPN1), HAMP - 582AG (hepcidin; HEPC), HFE C282Y and H63D (homeostatic iron regulator), TF P570S (transferrin) and SOD2 A16V in the mitochondrial superoxide dismutase-2 gene. Among patients, SLC40A1 - 8GG homozygotes were overrepresented (8.25% vs 2.62%; P = 0.0015) as well SOD2 16VV genotype (32.0% vs 24.3%; P = 0.037) accounting for increased SSNHL risk (OR = 3.34; 1.54-7.29 and OR = 1.47; 1.02-2.12, respectively). Moreover, LINE-1 methylation was inversely related (r2 = 0.042; P = 0.001) with hearing loss score assessed as pure tone average (PTA, dB HL), and the trend was maintained after SLC40A1 - 8CG and HAMP - 582AG genotype stratification (ΔSLC40A1 = + 8.99 dB HL and ΔHAMP = - 6.07 dB HL). In multivariate investigations, principal component analysis (PCA) yielded PC1 (PTA, age, LINE-1, HAMP, SLC40A1) and PC2 (sex, HFEC282Y, SOD2, HAMP) among the five generated PCs, and logistic regression analysis ascribed to PC1 an inverse association with moderate/severe/profound HL (OR = 0.60; 0.42-0.86; P = 0.0006) and with severe/profound HL (OR = 0.52; 0.35-0.76; P = 0.001). CONCLUSION: Recognizing genetic and epigenetic biomarkers and their mutual interactions in SSNHL is of great value and can help pharmacy science to design by pharmacogenomic data classical or advanced molecules, such as epidrugs, to target new pathways for a better prognosis and treatment of SSNHL.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Humanos , Metilação de DNA , Ferro/metabolismo , Ferro/uso terapêutico , Transferrina/genética , Transferrina/metabolismo , Transferrina/uso terapêutico , Perda Auditiva Neurossensorial/genética , Perda Auditiva Súbita/tratamento farmacológico , Perda Auditiva Súbita/genética , Homeostase/genética
10.
Biopolymers ; 115(2): e23569, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37970979

RESUMO

This study aimed to investigate the three different methods for the fabrication of quercetin (1%-3% w/w of protein) incorporated soy protein isolate (SPI) films and their effect on material properties. The quercetin incorporated SPI films prepared by these methods were characterized by Fourier transform infrared (FTIR) spectroscopy, UV-Vis spectrophotometer, tensile properties, and water uptake and leaching properties. The cross-linking pattern was revealed by the FTIR spectrum that showed formation of an ester group because of interaction between the quercetin hydroxyl group and the carboxyl side chain of SPI amino acids. The tensile strength of SPI films were enhanced with the addition of quercetin as it increased to a maximum of 6.17 MPa while neat SPI film had tensile strength 4.13 MPa. The prepared films exhibit significant antibacterial activity against Listeria monocytogenes and Escherichia coli. The In-silico docking analysis demonstrates that covalent and non-covalent forces play crucial roles in binding interaction. It shows the formation of four hydrogen bonds, two salt bridges along with one pi-alkyl interaction. The simulation studies reflect the crucial amino acid residues involved in SPI-quercetin binding. The effect of quercetin binding with SPI on its stability and compactness is revealed by Root mean square deviation (RMSD) and radius of gyration studies.


Assuntos
Quercetina , Proteínas de Soja , Proteínas de Soja/química , Simulação de Acoplamento Molecular , Quercetina/farmacologia , Resistência à Tração , Antibacterianos/farmacologia
11.
FASEB J ; 37(7): e23018, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37310411

RESUMO

Early detection, accurate monitoring, and therapeutics are major problems in non-small-cell lung cancer (NSCLC) patients. We identified genomic copy number variation of a unique panel of 40 mitochondria-targeted genes in NSCLCs (GEOGSE #29365). Validation of mRNA expression of these molecules revealed an altered panel of 34 genes in lung adenocarcinomas (LUAD) and 36 genes in lung squamous cell carcinomas (LUSC). In the LUAD subtype (n = 533), we identified 29 upregulated and 5 downregulated genes, while in the LUSC subtype (n = 502), a panel of 30 upregulated and 6 downregulated genes were discovered. The majority of these genes are associated with mitochondrial protein transport, ferroptosis, calcium signaling, metabolism, OXPHOS function, TCA cycle, apoptosis, and MARylation. Altered mRNA expression of SLC25A4, ACSF2, MACROD1, and GCAT was associated with poor survival of the NSCLC patients. Progressive loss of SLC25A4 protein expression was confirmed in NSCLC tissues (n = 59), predicting poor survival of the patients. Forced overexpression of SLC25A4 in two LUAD cell lines inhibited their growth, viability, and migration. A significant association of the altered mitochondrial pathway genes with LC subtype-specific classical molecular signatures was observed, implicating the existence of nuclear-mitochondrial cross-talks. Key alteration signatures shared between LUAD and LUSC subtypes including SLC25A4, ACSF2, MACROD1, MDH2, LONP1, MTHFD2, and CA5A could be helpful in developing new biomarkers and therapeutics.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Variações do Número de Cópias de DNA , Neoplasias Pulmonares/genética , Carcinoma de Células Escamosas/genética , Sinalização do Cálcio , DNA Mitocondrial , RNA Mensageiro , Proteínas Mitocondriais/genética , Proteases Dependentes de ATP
12.
J Vasc Interv Radiol ; 35(6): 900-908.e2, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508448

RESUMO

PURPOSE: To develop a noninvasive therapeutic approach able to alter the biophysical organization and physiology of the extracellular matrix (ECM) in breast cancer. MATERIALS AND METHODS: In a 4T1 murine model of breast cancer, histoplasty treatment with a proprietary 700-kHz multielement therapy transducer using a coaxially aligned ultrasound (US) imaging probe was used to target the center of an ex vivo tumor and deliver subablative acoustic energy. Tumor collagen morphology was qualitatively evaluated before and after histoplasty with second harmonic generation. Separately, mice bearing bilateral 4T1 tumors (n = 4; total tumors = 8) were intravenously injected with liposomal doxorubicin. The right flank tumor was histoplasty-treated, and tumors were fluorescently imaged to detect doxorubicin uptake after histoplasty treatment. Next, 4T1 tumor-bearing mice were randomized into 2 treatment groups (sham vs histoplasty, n = 3 per group). Forty-eight hours after sham/histoplasty treatment, tumors were harvested and analyzed using flow cytometry. RESULTS: Histoplasty significantly increased (P = .002) liposomal doxorubicin diffusion into 4T1 tumors compared with untreated tumors (2.12- vs 1.66-fold increase over control). Flow cytometry on histoplasty-treated tumors (n = 3) demonstrated a significant increase in tumor macrophage frequency (42% of CD45 vs 33%; P = .022) and a significant decrease in myeloid-derived suppressive cell frequency (7.1% of CD45 vs 10.3%; P = .044). Histoplasty-treated tumors demonstrated increased CD8+ (5.1% of CD45 vs 3.1%; P = .117) and CD4+ (14.1% of CD45 vs 11.8%; P = .075) T-cell frequency. CONCLUSIONS: Histoplasty is a nonablative focused US approach to noninvasively modify the tumor ECM, increase chemotherapeutic uptake, and alter the tumor immune microenvironment.


Assuntos
Doxorrubicina , Camundongos Endogâmicos BALB C , Microambiente Tumoral , Animais , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Linhagem Celular Tumoral , Camundongos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/cirurgia , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias da Mama/patologia , Transdutores , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Polietilenoglicóis/química , Modelos Animais de Doenças , Antígenos Comuns de Leucócito
13.
Indian J Med Res ; 159(2): 163-180, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38577857

RESUMO

ABSTRACT: From an initial thought of being used as a cellular garbage bin to a promising target for liquid biopsies, the role of exosomes has drastically evolved in just a few years of their discovery in 1983. Exosomes are naturally secreted nano-sized vesicles, abundant in all types of body fluids and can be isolated intact even from the stored biological samples. Being stable carriers of genetic material (cellular DNA, mRNA and miRNA) and having specific cargo (signature content of originating cells), exosomes play a crucial role in pathogenesis and have been identified as a novel source of biomarkers in a variety of disease conditions. Recently exosomes have emerged as a promising 'liquid biopsy tool'and have shown great potential in the field of non-invasive disease diagnostics, prognostics and treatment response monitoring in both communicable as well as non-communicable diseases. However, there are certain limitations to overcome which restrict the use of exosome-based liquid biopsy as a gold standard testing procedure in routine clinical practices. The present review summarizes the current knowledge on the role of exosomes as the liquid biopsy tool in diagnosis, prognosis and treatment response monitoring in communicable and non-communicable diseases and highlights the major limitations, technical advancements and future prospects of the utilization of exosome-based liquid biopsy in clinical interventions.


Assuntos
Exossomos , Doenças não Transmissíveis , Humanos , Exossomos/genética , Exossomos/patologia , Biópsia Líquida/métodos , Prognóstico , Biomarcadores
14.
Indian J Med Res ; 159(2): 223-231, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517215

RESUMO

BACKGROUND OBJECTIVES: The Omicron sub-lineages are known to have higher infectivity, immune escape and lower virulence. During December 2022 - January 2023 and March - April 2023, India witnessed increased SARS-CoV-2 infections, mostly due to newer Omicron sub-lineages. With this unprecedented rise in cases, we assessed the neutralization potential of individuals vaccinated with ChAdOx1 nCoV (Covishield) and BBV152 (Covaxin) against emerging Omicron sub-lineages. METHODS: Neutralizing antibody responses were measured in the sera collected from individuals six months post-two doses (n=88) of Covishield (n=44) or Covaxin (n=44) and post-three doses (n=102) of Covishield (n=46) or Covaxin (n=56) booster dose against prototype B.1 strain, lineages of Omicron; XBB.1, BQ.1, BA.5.2 and BF.7. RESULTS: The sera of individuals collected six months after the two-dose and the three-dose demonstrated neutralizing activity against all variants. The neutralizing antibody (NAbs) level was highest against the prototype B.1 strain, followed by BA5.2 (5-6 fold lower), BF.7 (11-12 fold lower), BQ.1 (12 fold lower) and XBB.1 (18-22 fold lower). INTERPRETATION CONCLUSIONS: Persistence of NAb responses was comparable in individuals with two- and three-dose groups post six months of vaccination. Among the Omicron sub-variants, XBB.1 showed marked neutralization escape, thus pointing towards an eventual immune escape, which may cause more infections. Further, the correlation of study data with complete clinical profile of the participants along with observations for cell-mediated immunity may provide a clear picture for the sustained protection due to three-dose vaccination as well as hybrid immunity against the newer variants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , ChAdOx1 nCoV-19 , Vacinas de Produtos Inativados , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Neutralizantes , Vacinação , Anticorpos Antivirais
15.
J Public Health (Oxf) ; 46(2): 256-266, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38291897

RESUMO

BACKGROUND: efficacy of therapeutic cholecalciferol supplementation for severe COVID-19 is sparingly studied. OBJECTIVE: effect of single high-dose cholecalciferol supplementation on sequential organ failure assessment (SOFA) score in moderate-to-severe COVID-19. METHODS: participants with moderate to severe COVID-19 with PaO2/FiO2 ratio < 200 were randomized to 0.6 million IU cholecalciferol oral (intervention) or placebo. OUTCOMES: primary outcome was change in Day 7 SOFA score and pre-specified secondary outcomes were SOFA and 28-day all-cause mortality. RESULTS: in all, 90 patients (45 each group) were included for intention-to-treat analysis. 25(OH)D3 levels were 12 (10-16) and 13 (12-18) ng/ml (P = 0.06) at baseline; and 60 (55-65) ng/ml and 4 (1-7) ng/ml by Day 7 in vitamin D and placebo groups, respectively. The SOFA score on Day 7 was better in the vitamin D group [3 (95% CI, 2-5) versus 5 (95% CI, 3-7), P = 0.01, intergroup difference - 2 (95% CI, -4 to -0.01); r = 0.4]. A lower all-cause 28-day mortality [24% compared to 44% (P = 0.046)] was observed with vitamin D. CONCLUSIONS: single high-dose oral cholecalciferol supplementation on ICU admission can improve SOFA score at Day 7 and reduce in-hospital mortality in vitamin D-deficient COVID-19. ClinicalTrials.gov  id: NCT04952857 registered dated 7 July 2021. What is already known on this topic-vitamin D has immunomodulatory role. Observational and isolated intervention studies show some benefit in COVID-19. Targeted therapeutic vitamin D supplementation improve outcomes in severe COVID-19 is not studied in RCTs. What this study adds-high-dose vitamin D supplementation (0.6 Million IU) to increase 25(OH)D > 50 ng/ml is safe and reduces sequential organ failure assessment score, in-hospital mortality in moderate to severe COVID-19. How this study might affect research, practice or policy-vitamin D supplementation in vitamin D-deficient patients with severe COVID-19 is useful may be practiced.


Assuntos
COVID-19 , Colecalciferol , SARS-CoV-2 , Deficiência de Vitamina D , Humanos , Masculino , Feminino , Método Duplo-Cego , Pessoa de Meia-Idade , COVID-19/mortalidade , COVID-19/complicações , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/complicações , Colecalciferol/administração & dosagem , Colecalciferol/uso terapêutico , Idoso , Vitamina D/sangue , Vitaminas/uso terapêutico , Vitaminas/administração & dosagem , Escores de Disfunção Orgânica , Suplementos Nutricionais , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/mortalidade , Tratamento Farmacológico da COVID-19 , Pandemias , Adulto , Resultado do Tratamento , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/mortalidade , Índice de Gravidade de Doença , Betacoronavirus
16.
Int J Health Plann Manage ; 39(2): 530-540, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38163283

RESUMO

OBJECTIVES: Literature states a higher self-contamination rate among healthcare workers (HCWs) while doffing personal protective equipment (PPE). During the Covid-19 pandemic, onsite trained observers were not always available to monitor PPE compliance. The remote audio-visual doffing surveillance (RADS) system has the potential to overcome this limitation. We aimed to compare the efficacy of this real-time RADS system against the onsite buddy system for monitoring the doffing of PPE. METHODS: This prospective, observational study was carried out at our tertiary care centre in northern India. 200 HCWs who cared for Covid-19 patients in the intensive care units/operation theatres were included. Group A included HCWs who performed doffing with the help of an onsite trained observer and group B included HCWs who performed doffing with the RADS system. An independent observer noted the error at any step using the CDC doffing checklist, in both groups. An online questionnaire to analyse the level of satisfaction post-doffing was also surveyed. RESULTS: The proportion of errors committed during doffing was significantly lower in group B compared to group A with a low relative risk of 0.34 (95% CI 0.22-0.51) (p < 0.001) (Figure 1A,B). In both groups, there was no difference in HCWs feedback regarding the ease of the system and fear of committing an error. Though the perceived quality of monitoring was felt better with onsite buddy, the overall confidence rating of being safe after doffing was better with the RADS system. CONCLUSION: Real-time RADS system may be more effective than the onsite buddy system for ensuring the safety of HCWs during doffing PPE. HCWs level of satisfaction related to the ease and anxiety with the monitoring systems were comparable. RADS system can reduce reliance on HCW resources and can integrate well into existing healthcare systems.


Assuntos
COVID-19 , Humanos , Pandemias/prevenção & controle , Estudos Prospectivos , Ansiedade , Lista de Checagem
17.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38473699

RESUMO

Prostate cancer (PCa) is the second most common cancer and the fifth highest cause of cancer-related death among men in the world [...].


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/terapia , Progressão da Doença
18.
Semin Cancer Biol ; 80: 237-255, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32470379

RESUMO

The development of cancer is not just the growth and proliferation of a single transformed cell, but its surrounding environment also coevolves with it. Indeed, successful cancer progression depends on the ability of the tumor cells to develop a supportive tumor microenvironment consisting of various types of stromal cells. The interactions between the tumor and stromal cells are bidirectional and mediated through a variety of growth factors, cytokines, metabolites, and other biomolecules secreted by these cells. Tumor-stromal crosstalk creates optimal conditions for the tumor growth, metastasis, evasion of immune surveillance, and therapy resistance, and its targeting is being explored for clinical management of cancer. Natural agents from plants and marine life have been at the forefront of traditional medicine. Numerous epidemiological studies have reported the health benefits imparted on the consumption of certain fruits, vegetables, and their derived products. Indeed, a significant majority of anti-cancer drugs in clinical use are either naturally occurring compounds or their derivatives. In this review, we describe fundamental cellular and non-cellular components of the tumor microenvironment and discuss the significance of natural compounds in their targeting. Existing literature provides hope that novel prevention and therapeutic approaches will emerge from ongoing scientific efforts leading to the reduced tumor burden and improve clinical outcomes in cancer patients.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Células Estromais/metabolismo , Microambiente Tumoral
19.
J Cell Biochem ; 124(4): 545-556, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36815439

RESUMO

The Nucleoside diphosphate kinase (NDK) protein of Porphyromonas gingivalis (P. gingivalis) plays a crucial role in immune evasion and inhibition of apoptosis in host cells and has the potential to cause cancer. However, its structure has not yet been characterized. We used an in-silico approach to determine the 3D structure of the P. gingivalis NDK. Furthermore, structural characterization and functional annotation were performed using computational approaches. The 3D structure of NDK was predicted through homology modeling. The structural domains predicted for the model protein belong to the NDK family. Structural alignment of prokaryotic and eukaryotic NDKs with the model protein revealed the conservation of the domain region. Structure-based phylogenetic analysis depicted a significant evolutionary relationship between the model protein and the prokaryotic NDK. Functional annotation of the model confirmed structural homology, exhibiting similar enzymatic functions as NDK, including ATP binding and nucleoside diphosphate kinase activity. Furthermore, molecular dynamic (MD) simulation technique stabilized the model structure and provides a thermo-stable protein structure that can be used as a therapeutic target for further studies.


Assuntos
Núcleosídeo-Difosfato Quinase , Núcleosídeo-Difosfato Quinase/genética , Núcleosídeo-Difosfato Quinase/química , Núcleosídeo-Difosfato Quinase/metabolismo , Proteínas Reguladoras de Apoptose , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo , Filogenia , Apoptose
20.
Kidney Int ; 103(6): 1180-1192, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36868377

RESUMO

The ASCEND-NHQ trial evaluated the effects of daprodustat on hemoglobin and the Medical Outcomes Study 36-item Short Form Survey (SF-36) Vitality score (fatigue) in a multicenter, randomized, double-blind, placebo-controlled trial. Adults with chronic kidney disease (CKD) stages 3-5, hemoglobin 8.5-10.0 g/dl, transferrin saturation 15% or more, and ferritin 50 ng/ml or more without recent erythropoiesis-stimulating agent use were randomized (1:1) to oral daprodustat or placebo to achieve and maintain target hemoglobin of 11-12 g/dl over 28 weeks. The primary endpoint was the mean change in hemoglobin between baseline and the evaluation period (Weeks 24-28). Principal secondary endpoints were proportion of participants with a 1 g/dl or more increase in hemoglobin and mean change in the Vitality score between baseline and Week 28. Outcome superiority was tested (1-sided alpha level of 0.025). Overall, 614 participants with non-dialysis-dependent CKD were randomized. The adjusted mean change in hemoglobin from baseline to the evaluation period was greater with daprodustat (1.58 vs 0.19 g/dl). The adjusted mean treatment difference (AMD) was significant at 1.40 g/dl (95% confidence interval 1.23, 1.56). A significantly greater proportion of participants receiving daprodustat showed a 1 g/dl or greater increase in hemoglobin from baseline (77% vs 18%). The mean SF-36 Vitality score increased by 7.3 and 1.9 points with daprodustat and placebo, respectively; a clinically and statistically significant 5.4 point Week 28 AMD increase. Adverse event rates were similar (69% vs 71%); relative risk 0.98, (95% confidence interval 0.88, 1.09). Thus, in participants with CKD stages 3-5, daprodustat resulted in a significant increase in hemoglobin and improvement in fatigue without an increase in the overall frequency of adverse events.


Assuntos
Hematínicos , Insuficiência Renal Crônica , Adulto , Humanos , Qualidade de Vida , Hemoglobinas/análise , Barbitúricos/efeitos adversos , Hematínicos/efeitos adversos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA