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1.
RNA ; 30(4): 392-403, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38282417

RESUMEN

The Mango I and II RNA aptamers have been widely used in vivo and in vitro as genetically encodable fluorogenic markers that undergo large increases in fluorescence upon binding to their ligand, TO1-Biotin. However, while studying nucleic acid sequences, it is often desirable to have trans-acting probes that induce fluorescence upon binding to a target sequence. Here, we rationally design three types of light-up RNA Mango Beacons based on a minimized Mango core that induces fluorescence upon binding to a target RNA strand. Our first design is bimolecular in nature and uses a DNA inhibition strand to prevent folding of the Mango aptamer core until binding to a target RNA. Our second design is unimolecular in nature, and features hybridization arms flanking the core that inhibit G-quadruplex folding until refolding is triggered by binding to a target RNA strand. Our third design builds upon this structure, and incorporates a self-inhibiting domain into one of the flanking arms that deliberately binds to, and precludes folding of, the aptamer core until a target is bound. This design separates G-quadruplex folding inhibition and RNA target hybridization into separate modules, enabling a more universal unimolecular beacon design. All three Mango Beacons feature high contrasts and low costs when compared to conventional molecular beacons, with excellent potential for in vitro and in vivo applications.


Asunto(s)
Aptámeros de Nucleótidos , Mangifera , ARN/genética , Mangifera/genética , Mangifera/metabolismo , Colorantes Fluorescentes/química , Aptámeros de Nucleótidos/química , Hibridación de Ácido Nucleico
2.
Proc Natl Acad Sci U S A ; 120(34): e2309516120, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37590407

RESUMEN

Here, we introduce the full functional reconstitution of genetically validated core protein machinery (SNAREs, Munc13, Munc18, Synaptotagmin, and Complexin) for synaptic vesicle priming and release in a geometry that enables detailed characterization of the fate of docked vesicles both before and after release is triggered with Ca2+. Using this setup, we identify new roles for diacylglycerol (DAG) in regulating vesicle priming and Ca2+-triggered release involving the SNARE assembly chaperone Munc13. We find that low concentrations of DAG profoundly accelerate the rate of Ca2+-dependent release, and high concentrations reduce clamping and permit extensive spontaneous release. As expected, DAG also increases the number of docked, release-ready vesicles. Dynamic single-molecule imaging of Complexin binding to release-ready vesicles directly establishes that DAG accelerates the rate of SNAREpin assembly mediated by chaperones, Munc13 and Munc18. The selective effects of physiologically validated mutations confirmed that the Munc18-Syntaxin-VAMP2 "template" complex is a functional intermediate in the production of primed, release-ready vesicles, which requires the coordinated action of Munc13 and Munc18.


Asunto(s)
Diglicéridos , Vesículas Sinápticas , Humanos , Exocitosis , Transmisión Sináptica , Sinaptotagminas , Vesícula
3.
FASEB J ; 38(5): e23512, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38430220

RESUMEN

The robust integrity of the retinal pigment epithelium (RPE), which contributes to the outer brain retina barrier (oBRB), is compromised in several retinal degenerative and vascular disorders, including diabetic macular edema (DME). This study evaluates the role of a new generation of histone deacetylase inhibitor (HDACi), ITF2357, in regulating outer blood-retinal barrier function and investigates the underlying mechanism of action in inhibiting TNFα-induced damage to RPE integrity. Using the immortalized RPE cell line (ARPE-19), ITF2357 was found to be non-toxic between 50 nM and 5 µM concentrations. When applied as a pre-treatment in conjunction with an inflammatory cytokine, TNFα, the HDACi was safe and effective in preventing epithelial permeability by fortifying tight junction (ZO-1, -2, -3, occludin, claudin-1, -2, -3, -5, -19) and adherens junction (E-cadherin, Nectin-1) protein expression post-TNFα stress. Mechanistically, ITF2357 depicted a late action at 24 h via attenuating IKK, IκBα, and p65 phosphorylation and ameliorated the expression of IL-1ß, IL-6, and MCP-1. Also, ITF2357 delayed IκBα synthesis and turnover. The use of Bay 11-7082 and MG132 further uncovered a possible role for ITF2357 in non-canonical NF-κB activation. Overall, this study revealed the protection effects of ITF2357 by regulating the turnover of tight and adherens junction proteins and modulating NF-κB signaling pathway in the presence of an inflammatory stressor, making it a potential therapeutic application for retinal vascular diseases such as DME with compromised outer blood-retinal barrier.


Asunto(s)
Retinopatía Diabética , Ácidos Hidroxámicos , Edema Macular , Humanos , FN-kappa B/metabolismo , Retinopatía Diabética/metabolismo , Inhibidor NF-kappaB alfa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Edema Macular/metabolismo , Transducción de Señal , Epitelio Pigmentado de la Retina/metabolismo , Barrera Hematorretinal/metabolismo , Uniones Estrechas/metabolismo , Células Epiteliales/metabolismo , Pigmentos Retinianos/metabolismo , Pigmentos Retinianos/farmacología , Pigmentos Retinianos/uso terapéutico
4.
Proc Natl Acad Sci U S A ; 119(38): e2208337119, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36103579

RESUMEN

Synchronous release at neuronal synapses is accomplished by a machinery that senses calcium influx and fuses the synaptic vesicle and plasma membranes to release neurotransmitters. Previous studies suggested the calcium sensor synaptotagmin (Syt) is a facilitator of vesicle docking and both a facilitator and inhibitor of fusion. On phospholipid monolayers, the Syt C2AB domain spontaneously oligomerized into rings that are disassembled by Ca2+, suggesting Syt rings may clamp fusion as membrane-separating "washers" until Ca2+-mediated disassembly triggers fusion and release [J. Wang et al., Proc. Natl. Acad. Sci. U.S.A. 111, 13966-13971 (2014)].). Here, we combined mathematical modeling with experiment to measure the mechanical properties of Syt rings and to test this mechanism. Consistent with experimental results, the model quantitatively recapitulates observed Syt ring-induced dome and volcano shapes on phospholipid monolayers and predicts rings are stabilized by anionic phospholipid bilayers or bulk solution with ATP. The selected ring conformation is highly sensitive to membrane composition and bulk ATP levels, a property that may regulate vesicle docking and fusion in ATP-rich synaptic terminals. We find the Syt molecules hosted by a synaptic vesicle oligomerize into a halo, unbound from the vesicle, but in proximity to sufficiently phosphatidylinositol 4,5-bisphosphate (PIP2)-rich plasma membrane (PM) domains, the PM-bound trans Syt ring conformation is preferred. Thus, the Syt halo serves as landing gear for spatially directed docking at PIP2-rich sites that define the active zones of exocytotic release, positioning the Syt ring to clamp fusion and await calcium. Our results suggest the Syt ring is both a Ca2+-sensitive fusion clamp and a high-fidelity sensor for directed docking.


Asunto(s)
Vesículas Sinápticas , Sinaptotagmina I , Adenosina Trifosfato/metabolismo , Calcio/metabolismo , Fosfatidilinositol 4,5-Difosfato/química , Vesículas Sinápticas/metabolismo , Sinaptotagmina I/química
5.
Am J Physiol Renal Physiol ; 326(3): F511-F533, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38234298

RESUMEN

Antibodies are one of the most used reagents in scientific laboratories and are critical components for a multitude of experiments in physiology research. Over the past decade, concerns about many biological methods, including those that use antibodies, have arisen as several laboratories were unable to reproduce the scientific data obtained in other laboratories. The lack of reproducibility could be largely attributed to inadequate reporting of detailed methods, no or limited verification by authors, and the production and use of unvalidated antibodies. The goal of this guideline article is to review best practices concerning commonly used techniques involving antibodies, including immunoblotting, immunohistochemistry, and flow cytometry. Awareness and integration of best practices will increase the rigor and reproducibility of these techniques and elevate the quality of physiology research.


Asunto(s)
Anticuerpos , Reproducibilidad de los Resultados , Inmunohistoquímica , Citometría de Flujo , Especificidad de Anticuerpos
6.
Int J Cancer ; 154(11): 1911-1919, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38339849

RESUMEN

Ovarian cancer (OC) is the fourth most common cancer of women in sub-Saharan Africa (SSA), although few data have been published on population-level survival. We estimate ovarian cancer survival in SSA by human development index and histological subtype, using data from seven population-based cancer registries in six countries: Kenya (Nairobi and Eldoret), Mauritius, Uganda (Kampala), Cote d'Ivoire (Abidjan), Ethiopia (Addis Ababa) and South Africa (Eastern Cape). A total of 644 cases diagnosed during 2008-2014 were included, with 77% being of epithelial subtypes (range 47% [Abidjan]-80% [Mauritius]). The overall observed survival in the study cohort was 73.4% (95% CI: 69.8, 77.0) at 1 year, 54.4% (95% CI: 50.4, 58.7) at 3 years and 45.0% (95% CI: 41.0, 49.4) at 5 years. Relative survival at Year 1 ranged from 44.4% in Kampala to 86.3% in Mauritius, with a mean for the seven series of 67.4%. Relative survival was highest in Mauritius at 72.2% and lowest in Kampala, Uganda at 19.5%, with a mean of 47.8%. There was no difference in survival by age at diagnosis. Patients from high and medium HDI countries had significantly better survival than those from low HDI countries. Women with cancers of epithelial cell origin had much lower survival compared to women with other histological subtypes (p = .02). Adjusted for the young age of the African patients with ovarian cancer (44% aged <50) survival is much lower than in USA or Europe, and underlines the need for improvements in the access to diagnosis and treatment of OC in SSA.


Asunto(s)
Neoplasias Ováricas , Humanos , Femenino , Etiopía , Kenia , Côte d'Ivoire , Uganda/epidemiología , Neoplasias Ováricas/epidemiología , Sistema de Registros
7.
Int J Cancer ; 155(4): 675-682, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38568397

RESUMEN

In sub-Saharan Africa, colorectal cancer (CRC) has historically been considered a rare disease, although some previous studies have suggested that the incidence is increasing. We examine time trends in the incidence of CRC using data from 12 population-based cancer registries in 11 countries of sub-Saharan Africa that were able to provide time series data for periods of 12 or more years, or with earlier data with which recent rates may be compared. Age-standardized incidence rates were highest in the higher-income countries, and were increasing in all of the populations studied, and these increases were statistically significant in all but three. Current evidence has suggested a link between the increased adoption of western lifestyle habits with colorectal cancer, and along with increasing urbanization of African populations, there is an increase in body weight, as well as evidence of increasing consumption of meat, sugars, and alcohol.


Asunto(s)
Neoplasias Colorrectales , Sistema de Registros , Humanos , Neoplasias Colorrectales/epidemiología , África del Sur del Sahara/epidemiología , Incidencia , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Estilo de Vida
8.
PLoS Pathog ; 18(2): e1010342, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35192678

RESUMEN

Viral infection of the heart is a common but underappreciated cause of heart failure. Viruses can cause direct cardiac damage by lysing infected cardiomyocytes. Inflammatory immune responses that limit viral replication can also indirectly cause damage during infection, making regulatory factors that fine-tune these responses particularly important. Identifying and understanding these factors that regulate cardiac immune responses during infection will be essential for developing targeted treatments for virus-associated heart failure. Our laboratory has discovered Brain Expressed X-linked protein 1 (BEX1) as a novel stress-regulated pro-inflammatory factor in the heart. Here we report that BEX1 plays a cardioprotective role in the heart during viral infection. Specifically, we adopted genetic gain- and loss-of-function strategies to modulate BEX1 expression in the heart in the context of coxsackievirus B3 (CVB3)-induced cardiomyopathy and found that BEX1 limits viral replication in cardiomyocytes. Interestingly, despite the greater viral load observed in mice lacking BEX1, inflammatory immune cell recruitment in the mouse heart was profoundly impaired in the absence of BEX1. Overall, the absence of BEX1 accelerated CVB3-driven heart failure and pathologic heart remodeling. This result suggests that limiting inflammatory cell recruitment has detrimental consequences for the heart during viral infections. Conversely, transgenic mice overexpressing BEX1 in cardiomyocytes revealed the efficacy of BEX1 for counteracting viral replication in the heart in vivo. We also found that BEX1 retains its antiviral role in isolated cells. Indeed, BEX1 was necessary and sufficient to counteract viral replication in both isolated primary cardiomyocytes and mouse embryonic fibroblasts suggesting a broader applicability of BEX1 as antiviral agent that extended to viruses other than CVB3, including Influenza A and Sendai virus. Mechanistically, BEX1 regulated interferon beta (IFN-ß) expression in infected cells. Overall, our study suggests a multifaceted role of BEX1 in the cardiac antiviral immune response.


Asunto(s)
Infecciones por Coxsackievirus , Insuficiencia Cardíaca , Miocarditis , Virosis , Animales , Antivirales/farmacología , Enterovirus Humano B , Fibroblastos , Ratones , Miocitos Cardíacos , Virosis/genética , Replicación Viral
9.
Exp Eye Res ; 238: 109713, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37952722

RESUMEN

PURPOSE: Diabetic Retinopathy (DR) is associated with metabolic dysfunction in cells such as retinal pigmented epithelium (RPE). Small molecular weight microRNAs can simultaneously regulate multiple gene products thus having pivotal roles in disease pathogenesis. Since miR182-5p is involved in regulating glycolysis and angiogenesis, two pathologic processes of DR, we investigated its status in DR eyes and in high glucose model in vitro. METHOD: ology: Total RNA was extracted from vitreous humor of PDR (n = 48) and macular hole (n = 22) subjects followed by quantification of miR182-5p and its target genes. ARPE-19 cells, cultured in DMEM under differential glucose conditions (5 mM and 25 mM) were used for metabolic and biochemical assays. Cells were transfected with miRNA182 mimic or antagomir to evaluate the gain and loss of function effects. RESULTS: PDR patient eyes had high levels of miR182-5p levels (p < 0.05). RPE cells under high glucose stress elevated miR182-5p expression with altered glycolytic pathway drivers such as HK2, PFKP and PKM2 over extended durations. Additionally, RPE cells under high glucose conditions exhibited reduced FoxO1 and enhanced Akt activation. RPE cells transfected with miR182-5p mimic phenocopied the enhanced basal and compensatory glycolytic rates observed under high glucose conditions with increased VEGF secretion. Conversely, inhibiting miR182-5p reduced Akt activation, glycolytic pathway proteins, and VEGF while stabilizing FoxO1. CONCLUSION: Glycolysis-associated proteins downstream of the FoxO1-Akt axis were regulated by miR182-5p. Further, miR182-5p increased expression of VEGFR2 and VEGF levels, likely via inhibition of ZNF24. Thus, the FoxO1-Akt-glycolysis/VEGF pathway driving metabolic dysfunction with concurrent angiogenic signaling in PDR may be potentially targeted for treatment via miR182-5p modulation.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Hiperglucemia , MicroARNs , Humanos , Retinopatía Diabética/metabolismo , Glucosa/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
Mol Cell Biochem ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38413478

RESUMEN

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

11.
Cell Biol Int ; 48(8): 1185-1197, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38773713

RESUMEN

Lactate is an oncometabolite that play important role in tumor aggressiveness. Lactate from the tumor microenvironment (TME) is taken up by cancer cells as an energy resource via mitochondrial oxidative phosphorylation (or OXPHOS). In the present study, by using an online meta-analysis tool we demonstrated that in oral squamous cancer cells (OSCCs) glycolytic and OXPHOS governing genes are overexpressed, like in breast cancer. For experimental demonstration, we treated the OSCC cell line (SCC4) and breast cancer cells (MDA-MB-231) with sodium L-lactate and analyzed its effects on changes in EMT and migration. For the therapeutic intervention of lactate metabolism, we used AZD3965 (an MCT1 inhibitor), and 7ACC2 (an MPC inhibitor). Like breast cancer, oral cancer tissues showed increased transcripts of 12 genes that were previously shown to be associated with glycolysis and OXPHOS. We experimentally demonstrated that L-lactate treatment induced mesenchymal markers and migration of cancer cells, which was significantly neutralized by MPC inhibitor that is, 7ACC2. Such an effect on EMT status was not observed with AZD3965. Furthermore, we showed that lactate treatment increases the MPC1 expression in both cancer cells, and this might be the reason why cancer cells in the high lactate environment are more sensitive to 7ACC2. Overall, our present findings demonstrate that extracellular lactate positively regulates the MPC1 protein expression in cancer cells, thereby putting forward the notion of using 7ACC2 as a potential therapeutic alternative to inhibit malignant oxidative cancers. Future preclinical studies are warranted to validate the present findings.


Asunto(s)
Neoplasias de la Mama , Movimiento Celular , Transición Epitelial-Mesenquimal , Ácido Láctico , Transportadores de Ácidos Monocarboxílicos , Neoplasias de la Boca , Humanos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Femenino , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Neoplasias de la Boca/tratamiento farmacológico , Ácido Láctico/metabolismo , Movimiento Celular/efectos de los fármacos , Cumarinas/farmacología , Fosforilación Oxidativa/efectos de los fármacos , Glucólisis/efectos de los fármacos , Simportadores/metabolismo , Simportadores/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Microambiente Tumoral/efectos de los fármacos , Pirimidinonas , Tiofenos
12.
Environ Res ; 259: 119435, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38914255

RESUMEN

Herein, the study introduces a novel bifunctional In2S3/MgTiO3/TiO2@N-CNT (IMTNC) nanocomposite, which is poised to revolutionize the detection and removal of clothianidin (CLD) from aquatic environments by synergistic adsorption and photodegradation. Confirmation of the material's synthesis was done using structural, optical, morphological, and chemical characterizations. An outstanding sensitivity of 2.168 µA/nM.cm2 with a linear range of 4-100 nM and a LOD of 0.04 nM, along with an exceptional elimination efficiency of 98.06 ± 0.84% for about 10 ppm CLD within 18 min was demonstrated by the IMTNC nanocomposite. Extensive studies were carried out to appraise the material's effectiveness in the presence of various interfering species, such as cations, anions, organic compounds, and different water matrices, and a comprehensive assessment of its stability throughout several cycles was made. Response Surface Methodology (RSM) study was used to determine the ideal removal conditions for improved performance. In addition, the catalytic performance in removing various other pollutants was also analyzed. Adding In2S3 and developing N-doped Carbon Nanotubes (N-CNT) increased conductivity and higher electrochemical sensing skills, improving charge transfer and increasing photocatalytic activity. This research underscores the potential of the IMTNC nanocomposite as a promising candidate for advanced environmental sensing and remediation applications.

13.
J Endocrinol Invest ; 47(6): 1405-1418, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38218741

RESUMEN

OBJECTIVES: To examine the cross-sectional association between baseline depressive symptoms and the presence of type 2 diabetes (T2D), and its association with glycated hemoglobin (HbA1c) and other metabolic variables, and the prospective association of depressive symptoms and HbA1c after 1 year of follow-up. METHODS: n = 6224 Mediterranean older adults with overweight/obesity and metabolic syndrome (48% females, mean age 64.9 ± 4.9 years) were evaluated in the framework of the PREDIMED-Plus study cohort. Depressive symptoms were assessed using the Beck Depression Inventory-II and HbA1c was used to measure metabolic control. RESULTS: The presence of T2D increased the likelihood of higher levels of depressive symptoms (χ2 = 15.84, p = 0.001). Polynomial contrast revealed a positive linear relationship (χ2 = 13.49, p = 0.001), the higher the depressive symptoms levels, the higher the prevalence of T2D. Longitudinal analyses showed that the higher baseline depressive symptoms levels, the higher the likelihood of being within the HbA1c ≥ 7% at 1-year level (Wald-χ2 = 24.06, df = 3, p < .001, for the full adjusted model). Additionally, depressive levels at baseline and duration of T2D predicted higher HbA1c and body mass index, and lower physical activity and adherence to Mediterranean Diet at 1 year of follow-up. CONCLUSIONS: This study supports an association between T2D and the severity of depressive symptoms, suggesting a worse metabolic control from mild severity levels in the short-medium term, influenced by lifestyle habits related to diabetes care. Screening for depressive symptoms and a multidisciplinary integrative therapeutic approach should be ensured in patients with T2D.


Asunto(s)
Depresión , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Estudios de Seguimiento , Depresión/epidemiología , Depresión/etiología , Anciano , Estudios Transversales , Hemoglobina Glucada/análisis , Estudios Prospectivos , Dieta Mediterránea , Prevalencia , Índice de Masa Corporal , Obesidad/psicología , Obesidad/epidemiología , Obesidad/complicaciones , Síndrome Metabólico/epidemiología , Síndrome Metabólico/psicología
14.
Am J Dermatopathol ; 46(3): 170-172, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38170737

RESUMEN

ABSTRACT: Undifferentiated melanoma (UM) is defined by the loss of classic morphologic and immunohistochemical melanocytic markers. Reports in the literature are rare and show that UM usually occurs as a metastasis in the setting of a known primary cutaneous melanoma. The most common mutations in UM include those involving BRAF , NRAS , and KIT , which are almost invariably present in the parent melanoma. In this study, we report a case of a primary sinonasal melanoma with metastatic UM presenting with osteoclast-like giant cells and resembling a primary bone tumor. The retention of an unusual KRAS mutation in UM that was also present in the primary lesion provided critical information for the diagnosis. Our report highlights the importance of considering mutational analysis to identify undifferentiated melanomas in patients with metastatic tumors which do not have the typical histopathologic and immunohistochemical features of melanoma.


Asunto(s)
Neoplasias Óseas , Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Análisis Mutacional de ADN , Mutación , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/genética , Proteínas Proto-Oncogénicas B-raf/genética
15.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33468631

RESUMEN

Controlled release of neurotransmitters stored in synaptic vesicles (SVs) is a fundamental process that is central to all information processing in the brain. This relies on tight coupling of the SV fusion to action potential-evoked presynaptic Ca2+ influx. This Ca2+-evoked release occurs from a readily releasable pool (RRP) of SVs docked to the plasma membrane (PM). The protein components involved in initial SV docking/tethering and the subsequent priming reactions which make the SV release ready are known. Yet, the supramolecular architecture and sequence of molecular events underlying SV release are unclear. Here, we use cryoelectron tomography analysis in cultured hippocampal neurons to delineate the arrangement of the exocytosis machinery under docked SVs. Under native conditions, we find that vesicles are initially "tethered" to the PM by a variable number of protein densities (∼10 to 20 nm long) with no discernible organization. In contrast, we observe exactly six protein masses, each likely consisting of a single SNAREpin with its bound Synaptotagmins and Complexin, arranged symmetrically connecting the "primed" vesicles to the PM. Our data indicate that the fusion machinery is likely organized into a highly cooperative framework during the priming process which enables rapid SV fusion and neurotransmitter release following Ca2+ influx.


Asunto(s)
Proteínas del Tejido Nervioso/metabolismo , Terminales Presinápticos/metabolismo , Vesículas Sinápticas/metabolismo , Animales , Células Cultivadas , Microscopía por Crioelectrón , Hipocampo/citología , Imagenología Tridimensional , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuronas/ultraestructura , Terminales Presinápticos/ultraestructura , Vesículas Sinápticas/ultraestructura
16.
Public Health ; 230: 12-20, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38479163

RESUMEN

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD). METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption. CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.


Asunto(s)
Dieta Mediterránea , Gases de Efecto Invernadero , Humanos , Dieta , Ambiente , Recolección de Datos
17.
Molecules ; 29(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38542918

RESUMEN

Chymotrypsin, a crucial enzyme in human digestion, catalyzes the breakdown of milk proteins, underscoring its significance in both health diagnostics and dairy quality assurance. Addressing the critical need for rapid, cost-effective detection methods, we introduce a groundbreaking approach utilizing far-red technology and HOMO-Förster resonance energy transfer (FRET). Our novel probe, SQ-122 PC, features a unique molecular design that includes a squaraine dye (SQ), a peptide linker, and SQ moieties synthesized through solid-phase peptide synthesis. Demonstrating a remarkable quenching efficiency of 93.75% in a tailored H2O:DMSO (7:3) solvent system, our probe exhibits absorption and emission properties within the far-red spectrum, with an unprecedented detection limit of 0.130 nM. Importantly, our method offers unparalleled selectivity towards chymotrypsin, ensuring robust and accurate enzyme detection. This pioneering work underscores the immense potential of far-red-based homo-FRET systems in enabling the sensitive and specific detection of chymotrypsin enzyme activity. By bridging the gap between cutting-edge technology and biomedical diagnostics, our findings herald a new era of enzyme sensing, promising transformative advancements in disease diagnosis and dairy quality control.


Asunto(s)
Quimotripsina , Ciclobutanos , Colorantes Fluorescentes , Fenoles , Humanos , Colorantes Fluorescentes/química , Transferencia Resonante de Energía de Fluorescencia/métodos , Péptidos/química
18.
Int J Cancer ; 152(7): 1328-1336, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36274630

RESUMEN

Ovarian cancer (OC) is one of the commonest cancers of women in sub-Saharan Africa (SSA), although to date no data have been available on time trends in incidence to better understand the disease pattern in the region. We estimate time trends by histological subtype from 12 population-based cancer registries in 11 countries: Kenya (Nairobi), Mauritius, Seychelles, Uganda (Kampala), Congo (Brazzaville), Zimbabwe (Bulawayo and Harare), Cote d'Ivoire (Abidjan), The Gambia, Mali (Bamako), Nigeria (Ibadan) and South Africa (Eastern Cape). The selected registries were those that could provide consistent estimates of the incidence of ovarian cancer and with quality assessment for periods of 10 or more years. A total of 5423 cases of OC were included. Incidence rates have been increasing in all registries except Brazzaville, Congo, where a nonsignificant decline of 1% per year was seen. Statistically significant average annual increases were seen in Mauritius (2.5%), Bamako (5.3%), Ibadan (3.9%) and Eastern Cape (8%). Epithelial ovarian cancer was responsible for the increases observed in all registries. Statistically significant average annual percentage changes (AAPC) for epithelial OC were present in Bamako (AAPC = 5.9%), Ibadan (AAPC = 4.7%) and Eastern Cape (AAPC = 11.0%). Creating awareness among professionals of the growing importance of the disease is surely an important step to improving availability of, and access to, diagnosis and treatment of OC in SSA. Support must be given to the cancer registries to improve the availability of good-quality data on this important cancer.


Asunto(s)
Neoplasias Ováricas , Humanos , Femenino , Incidencia , Côte d'Ivoire/epidemiología , Kenia , Nigeria , Uganda , Zimbabwe , Neoplasias Ováricas/epidemiología , Carcinoma Epitelial de Ovario/epidemiología
19.
New Phytol ; 240(2): 555-564, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37537732

RESUMEN

Seed dormancy maximizes plant recruitment in habitats with variation in environmental suitability for seedling establishment. Yet, we still lack a comprehensive synthesis of the macroecological drivers of nondormancy and the different classes of seed dormancy: physiological dormancy, morphophysiological dormancy and physical dormancy. We examined current geographic patterns and environmental correlates of global seed dormancy variation. Combining the most updated data set on seed dormancy classes for > 10 000 species with > 4 million georeferenced species occurrences covering all of the world's biomes, we test how this distribution is driven by climate and fire regime. Seed dormancy is prevalent in seasonally cold and dry climates. Physiological dormancy occurs in relatively dry climates with high temperature seasonality (e.g. temperate grasslands). Morphophysiological dormancy is more common in forest-dominated, cold biomes with comparatively high and evenly distributed precipitation. Physical dormancy is associated with dry climates with strong seasonal temperature and precipitation fluctuations (e.g. deserts and savannas). Nondormancy is associated with stable, warm and wetter climates (e.g. tropical rain forest). Pyroclimate had no significant effect on the distribution of seed dormancy. The environmental drivers considered in this study had a comparatively low predictive power, suggesting that macroclimate is just one of several global drivers of seed dormancy.


Asunto(s)
Germinación , Latencia en las Plantas , Latencia en las Plantas/fisiología , Germinación/fisiología , Semillas/fisiología , Clima , Plantas , Temperatura , Estaciones del Año
20.
J Med Virol ; 95(8): e29019, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37543989

RESUMEN

Gamma-papillomaviruses, though traditionally classified as cutaneotropic, actual tissue tropism is largely unexplored. This study aimed to evaluate the tissue-specific prevalence of two novel-HPV 223 and 225 in samples of oral mucosa and keratinized epithelium of varied skin parts from 226 female and male subjects, with or without neoplastic/dysplastic lesions in oral cavity or cervix. The gamma-human papillomavirus (gamma-HPV) 223 and 225 DNA presences were determined by polymerase chain reaction (PCR) ursing the HPV type-specific primers and confirmed by Sanger sequencing. Viral load in the HPV 223 and HPV 225 positive samples were determined by absolute real-time quantification method. Alpha-HPV DNA prevalence was also checked in oral mucosa to ascertain coinfection status. Novel HPV 223 was present in 4.4% (10/226) oral mucosal samples of the study population; interestingly all were females with no prevalence in their corresponding skin swab samples. Whereas, the prevalence of HPV 225 was found both in the skin and oral mucosa of 28.2% (N = 37/131) female and 17.9% (N = 17/95) male participants. Alongside, HPV 223 viral load was found to be significantly higher (p = 0.02 < 0.05) in the oral mucosa of diseased participants, whereas, HPV 225 viral load was higher in the oral mucosa of normal participants. Our results suggest that gamma-HPV 223 has its prevalence only in the oral mucosal epithelium, whereas, HPV 225 has its prevalence on both mucosal and keratinized skin epithelium, indicating its dual tropism nature.


Asunto(s)
Infecciones por Papillomavirus , Humanos , Masculino , Femenino , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Boca , Mucosa Bucal , Papillomaviridae/genética , Piel , Virus del Papiloma Humano , ADN Viral/genética , ADN Viral/análisis
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