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1.
Nature ; 616(7957): 448-451, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36858072

RESUMEN

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (ß) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4-6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.

2.
Anal Chem ; 94(47): 16470-16480, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36318661

RESUMEN

Exceptional surface enhanced Raman scattering (SERS) can be achieved by on-demand mechanisms mediated by the formation of three-dimensional (3D) network supporting hotspots. Herein, a deep eutectic solvent (DES) is used to fabricate plasmonic aerogels as sustainable SERS substrates consisting of different gold nanoparticle (AuNP) heterostructures synthesized in the presence of cellulose nanocrystals (CNCs). This analytical approach is based on the AuNPs 3D arrangement within the CNC matrix, where the transient inter-CNCs interactions collapse after loading with the analyte aqueous solution, forming hotspots on demand. Theoretical calculations support the on-demand SERS mechanism, which consists of the hotspot formation by bringing the AuNPs closer upon activation with the liquid sample loading. To evaluate the plasmonic aerogel performance as a sensing platform, the organophosphorus pesticides edifenphos and parathion were tested in rice and tea extracts. Also, the detection of Methylene Blue in fish muscle extract resulted in a detection limit of 9.8 nM. The results demonstrate that the 3D plasmonic aerogel exhibits significantly higher SERS enhancement and sensitivity when compared to conventional 2D SERS substrates. The use of a green designer solvent, biobased ingredients, and the introduction of on-demand SERS-based sensing pave the way for further developments in the analysis of liquid samples within a sustainable framework.


Asunto(s)
Nanopartículas del Metal , Plaguicidas , Animales , Oro/química , Nanopartículas del Metal/química , Disolventes Eutécticos Profundos , Solventes , Compuestos Organofosforados , Espectrometría Raman/métodos , Celulosa/química
3.
Acta Chir Belg ; 122(6): 390-395, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33929304

RESUMEN

BACKGROUND: There is still a lack of clarity about the benefits of preoperative biliary drainage (PBD), which was introduced to improve the perioperative outcome in patients with obstructive jaundice caused by a periampullary tumour. The aim of this study was to determine whether operative and postoperative complications increase in patients undergoing PBD during pancreatoduodenectomy (PD). MATERIAL AND METHODS: Retrospective examination was made of patients who underwent PBD for a periampullary tumour in our hospital between 2006 and 2014. From these, the patients were identified who had PBD with endoscopic retrograde cholangiopancreatography and these patients were further separated into two groups, as one group of patients with plastic stents and the other group of patients with metallic stents. Patients with pancreas head cancer were also separated into two groups as those who were and were not applied with PBD. The preoperative, intraoperative and postoperative characteristics of the patients were evaluated. RESULTS: A total of 123 patients were retrospectively reviewed. Biliary stent placement with PBD was applied to 48 patients, of whom 31 had metallic stents and 17 had plastic stents. In general, there was no difference between the PBD and the non-PBD groups in respect of the preoperative, operative and postoperative results. When patients with tumour of the pancreas head only were examined, the rate of wound infection was higher in the PBD group and there was no difference in the other parameters. Moreover, there was no difference between the patients with metallic stents and those with plastic stents in respect of outcomes. CONCLUSIONS: With the exception of wound site infection, although no difference was observed between the PBD and the non-PBD groups based on intraoperative and postoperative complications, because of the distinctive inherent complications of PBD it is essential to manage such patients properly and to carefully select the patients for the PBD procedure.


Asunto(s)
Ictericia Obstructiva , Pancreatectomía , Humanos , Estudios Retrospectivos , Cuidados Preoperatorios/métodos , Resultado del Tratamiento , Drenaje/métodos , Pancreaticoduodenectomía/efectos adversos , Pancreaticoduodenectomía/métodos , Ictericia Obstructiva/etiología , Ictericia Obstructiva/cirugía , Stents/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Plásticos/efectos adversos , Neoplasias Pancreáticas
4.
Am J Physiol Gastrointest Liver Physiol ; 319(2): G121-G132, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32567324

RESUMEN

Nongenomic glucocorticoid (GC) and serum- and glucocorticoid-inducible kinase 1 (SGK1) signaling regulate ion transport, but CFTR has not been investigated in the intestine. We examined GC, SGK1, and phosphatidylinositol 3-kinase (PI3K) kinase signaling of CFTR ion transport in native intestine and the role of GCs on mRNA, protein, surface expression, and cyclic guanosine monophosphate (cGMP)-elicited diarrhea. Rats were treated with dexamethasone (DEXA; 2 mg/kg ip) or DMSO for 1, 4, and 24 h. Cyclic adenosine monophosphate (cAMP)-activated ion transport was examined in the presence or absence of SGK1 and PI3K inhibitors. Phosphorylation of SGK1, phosphoinositide-dependent kinase 1, and Akt kinases was confirmed by immunoblots using phosphor-specific antibodies. Tissue lysates were analyzed by mass spectrometry. CFTR and SGK1 mRNA were measured by quantitative PCR. Changes in total and surface CFTR protein were determined. The role of GC in cGMP-activated CFTR ion transport was examined. GC synergistically increased CFTR ion transport by SGK1 and PI3K signaling and increased CFTR protein without altering SGK1 or CFTR mRNA. GC induced highest levels of CFTR protein at 4 h that were associated with marked increase in surface CFTR, phosphorylation of the ubiquitin ligase neural precursor cell expressed developmentally downregulated 4-like (Nedd4-2), and 14-3-3ε, supporting their roles in surface retention and stability. Coimmunoprecipitation of CFTR, Nedd4-2, and 14-3-3ε indicated that assembly of this complex is a likely effector of the SGK and Akt pathways. Mass spectrometry identified phosphorylated peptides in relevant proteins. GC-SGK1 potently regulates CFTR in the intestine and is implicated in diarrheal disease.NEW & NOTEWORTHY This is the first study to examine the mechanisms of glucocorticoid, serum- and glucocorticoid-inducible kinase 1, and nongenomic kinase signaling of CFTR in the native intestine. We identified unique and druggable intestine-specific factors of the pathway that are targets for treating stress-induced diarrhea.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Dexametasona/toxicidad , Diarrea/etiología , Dimetilsulfóxido/toxicidad , Proteínas Inmediatas-Precoces/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Animales , Toxinas Bacterianas/toxicidad , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Diarrea/inducido químicamente , Enterotoxinas/toxicidad , Proteínas de Escherichia coli/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas Inmediatas-Precoces/genética , Masculino , Ubiquitina-Proteína Ligasas Nedd4/genética , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Transporte de Proteínas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Ratas , Ratas Sprague-Dawley , Intercambiador 3 de Sodio-Hidrógeno/genética , Intercambiador 3 de Sodio-Hidrógeno/metabolismo
5.
Prev Med ; 138: 106177, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32592795

RESUMEN

Suicide rates in Mexico have increased and have more than doubled in the state of Aguascalientes over the past 10 years. Few studies have been able to control for family, neighborhood, and occupational environment factors that may confound the association between psychosocial characteristics and suicidal behavior. We study suicidal behavior among adolescents and young adults in Mexico utilizing epidemiologic research strategies to overcome prior research deficiencies. In a case-control study with youth and adults 14-42 years of age, recent cases of severe suicidal behavior (n = 150) were individually matched with up to three controls who had never had a suicidal attempt by age and sex, as well as within familial, neighborhood, and occupational contexts (n = 353). Data were collected through standardized face-to-face interviews to measure suicidal behavior and several covariates, including family relations, psychological resources, hopelessness, depression, self-esteem, stress, impulsivity, anxiety, and substance use. All measures demonstrated good to excellent precision and accuracy. Compared with their matched controls, cases perceived life events as more stressful and had worse depression and familial relationships; poorer development of affective, religious, and social resources; higher levels of hopelessness and impulsive behavior; and lower self-esteem. Evidence from multivariate analysis suggests highly probable MDE combined with low self-esteem and the use of two or more drugs in the past month more clearly differentiate cases and controls and, therefore, may best predict suicidal attempt among adolescents and young adults in Aguascalientes, Mexico.


Asunto(s)
Ideación Suicida , Intento de Suicidio , Adolescente , Ansiedad , Estudios de Casos y Controles , Humanos , México , Factores de Riesgo , Adulto Joven
6.
J Cell Sci ; 127(Pt 16): 3568-77, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24876225

RESUMEN

Atypical PKC (ι/λ and ζ; hereafter referred to as aPKC) is a key player in the acquisition of epithelial polarity and participates in other signaling cascades including the control of NF-κB signaling. This kinase is post-translationally regulated through Hsp70-mediated refolding. Previous work has shown that such a chaperoning activity is specifically localized to keratin intermediate filaments. Our work was performed with the goal of identifying the molecule(s) that block Hsp70 activity on keratin filaments during inflammation. A transcriptional screen allowed us to focus on BAG-1, a multi-functional protein that assists Hsp70 in nucleotide exchange but also blocks its activity at higher concentrations. We found the BAG-1 isoform BAG-1M upregulated threefold in human Caco-2 cells following stimulation with tumor necrosis factor receptor α (TNFα) to induce a pro-inflammatory response, and up to sixfold in mouse enterocytes following treatment with dextran sodium sulfate (DSS) to induce colitis. BAG-1M, but no other isoform, was found to co-purify with intermediate filaments and block Hsp70 activity in the keratin fraction but not in the soluble fraction within the range of concentrations found in epithelial cells cultured under control and inflammation conditions. Constitutive expression of BAG-1M decreased levels of phosphorylated aPKC. By contrast, knockdown of BAG-1, blocked the TNFα-induced decrease of phosphorylated aPKC. We conclude that BAG-1M mediates Hsp70 inhibition downstream of NF-κB.


Asunto(s)
Colitis/enzimología , Proteínas de Unión al ADN/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Intestino Delgado/metabolismo , Queratinas/metabolismo , Proteína Quinasa C/metabolismo , Factores de Transcripción/metabolismo , Animales , Células CACO-2 , Colitis/genética , Colitis/inmunología , Colitis/metabolismo , Proteínas de Unión al ADN/genética , Proteínas HSP70 de Choque Térmico/genética , Humanos , Intestino Delgado/enzimología , Intestino Delgado/inmunología , Queratinas/genética , Ratones , FN-kappa B/genética , FN-kappa B/metabolismo , Fosforilación , Proteína Quinasa C/genética , Factores de Transcripción/genética
7.
Am J Physiol Gastrointest Liver Physiol ; 307(10): G992-G1001, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25258405

RESUMEN

Microvillus inclusion disease (MVID) is an autosomal recessive condition resulting in intractable secretory diarrhea in newborns due to loss-of-function mutations in myosin Vb (Myo5b). Previous work suggested that the apical recycling endosomal (ARE) compartment is the primary location for phosphoinositide-dependent protein kinase 1 (PDK1) signaling. Because the ARE is disrupted in MVID, we tested the hypothesis that polarized signaling is affected by Myo5b dysfunction. Subcellular distribution of PDK1 was analyzed in human enterocytes from MVID/control patients by immunocytochemistry. Using Myo5b knockdown (kd) in Caco-2BBe cells, we studied phosphorylated kinases downstream of PDK1, electrophysiological parameters, and net water flux. PDK1 was aberrantly localized in human MVID enterocytes and Myo5b-deficient Caco-2BBe cells. Two PDK1 target kinases were differentially affected: phosphorylated atypical protein kinase C (aPKC) increased fivefold and phosohoprotein kinase B slightly decreased compared with control. PDK1 redistributed to a soluble (cytosolic) fraction and copurified with basolateral endosomes in Myo5b kd. Myo5b kd cells showed a decrease in net water absorption that could be reverted with PDK1 inhibitors. We conclude that, in addition to altered apical expression of ion transporters, depolarization of PDK1 in MVID enterocytes may lead to aberrant activation of downstream kinases such as aPKC. The findings in this work suggest that PDK1-dependent signaling may provide a therapeutic target for treating MVID.


Asunto(s)
Polaridad Celular , Enterocitos/metabolismo , Síndromes de Malabsorción/metabolismo , Microvellosidades/patología , Mucolipidosis/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Miosina Tipo V/metabolismo , Transducción de Señal , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/antagonistas & inhibidores , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Células CACO-2 , Estudios de Casos y Controles , Regulación hacia Abajo , Endosomas/metabolismo , Enterocitos/efectos de los fármacos , Humanos , Síndromes de Malabsorción/tratamiento farmacológico , Síndromes de Malabsorción/genética , Microvellosidades/genética , Microvellosidades/metabolismo , Terapia Molecular Dirigida , Mucolipidosis/tratamiento farmacológico , Mucolipidosis/genética , Mutación , Cadenas Pesadas de Miosina/genética , Miosina Tipo V/genética , Fosforilación , Proteína Quinasa C/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Transporte de Proteínas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Transfección , Agua/metabolismo
8.
Chemosphere ; 320: 138081, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36758819

RESUMEN

This work reports a sensitive SERS substrate based on graphene oxide (GO) and quantum-sized ZrO2 nanoparticles (GO/ZrO2) for label-free determination of the organophosphate pesticide methyl parathion (MP). The enhanced light-matter interactions and the consequent SERS effect in these substrates resulted from the effective charge transfer (CT) mechanism attributed to synergistic contributions of three main factors: i) the strong molecular adherence of the MP molecules and the ZrO2 surface which allows the first layer-effect, ii) the relatively abundant surface defects in low dimensional ZrO2 semiconductor NPs, which act as intermediate electronic states that reduce the large bandgap barrier, and iii) the hindered charge recombination derived from the transference of the photoinduced holes to the GO layer. This mechanism allowed an enhancement factor of 8.78 × 104 for GO/ZrO2-based substrates, which is more than 5-fold higher than the enhancement observed for platforms without GO. A detection limit of 0.12 µM was achieved with an outstanding repeatability (variation ≤4.5%) and a linear range up to 10 µM, which is sensitive enough to determine the maximal MP concentration permissible in drinking water according to international regulations. Furthermore, recovery rates between 97.4 and 102.1% were determined in irrigation water runoffs, strawberry and black tea extracts, demonstrating the reliability of the hybrid GO/ZrO2 substrate for the organophosphate pesticides quantification in samples related to agri-food sectors and environmental monitoring.


Asunto(s)
Grafito , Insecticidas , Nanopartículas del Metal , Metil Paratión , Reproducibilidad de los Resultados , Nanopartículas del Metal/química , Grafito/química
9.
Dalton Trans ; 51(31): 11630-11640, 2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-35861610

RESUMEN

Salicylic acid (SA) is a phenolic phytohormone with critical roles in plant growth regulation and resistance to biotic and abiotic stress. Since low SA concentrations can modulate many plant biochemical responses, innovative analytical tools are required to deeply understand its activity and to control its exogenous application in modern agricultural systems. Herein, a NIR-activated composite based on NaYF4:Yb,Er@NaYF4 core@shell upconversion nanoparticles decorated with the poly(allylamine)-Cu(II) complex [UCNPs-PAAm-Cu(II)] was developed to sensitively determine the SA molecule in plant-derived samples. Accordingly, the PAAm-Cu(II) complex grafted on the UCNPs induces a strategic charge transfer band which triggers a quenching process through a resonance energy transfer (RET) mechanism. Such process is gradually deactivated upon the addition of SA and the consequent formation of the SA-Cu(II) complex, allowing a luminescence recovery in the 1-800 nM linear range. This mechanism is promoted by the strong stability of the SA-Cu(II) complex (log ß2-SA/Cu = 19.01) which is over twelve orders of magnitude stronger than the PAAm-Cu2+ counterpart. Furthermore, the equilibrium and kinetic studies on the involved mononuclear Cu2+ complexes formation permitted instantaneous analytical responses and excellent selectivity against other representative phytohormones and metallic cations. The reliability of this method was demonstrated by determining the SA content of some edible fruits and vegetables comprising apple, lemon, kiwi, tomato, and cucumber, whose concentrations ranged from 0.30 to 2.99 µg g-1, with percent recoveries between 94.6 to 102.3%. Thereby, the reported nanocomplex can help to understand the SA activity in plants with significant applications in crop yield improvement and food quality assessment.


Asunto(s)
Alilamina , Nanopartículas , Cobre , Cinética , Nanopartículas/química , Extractos Vegetales , Reguladores del Crecimiento de las Plantas , Reproducibilidad de los Resultados , Ácido Salicílico
10.
J Clin Med ; 11(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35887942

RESUMEN

Microvillus inclusion disease (MVID), a lethal congenital diarrheal disease, results from loss of function mutations in the apical actin motor myosin VB (MYO5B). How loss of MYO5B leads to both malabsorption and fluid secretion is not well understood. Serum glucocorticoid-inducible kinase 1 (SGK1) regulates intestinal carbohydrate and ion transporters including cystic fibrosis transmembrane conductance regulator (CFTR). We hypothesized that loss of SGK1 could reduce CFTR fluid secretion and MVID diarrhea. Using CRISPR-Cas9 approaches, we generated R26CreER;MYO5Bf/f conditional single knockout (cMYO5BKO) and R26CreER;MYO5Bf/f;SGK1f/f double knockout (cSGK1/MYO5B-DKO) mice. Tamoxifen-treated cMYO5BKO mice resulted in characteristic features of human MVID including severe diarrhea, microvillus inclusions (MIs) in enterocytes, defective apical traffic, and depolarization of transporters. However, apical CFTR distribution was preserved in crypts and depolarized in villus enterocytes, and CFTR high expresser (CHE) cells were observed. cMYO5BKO mice displayed increased phosphorylation of SGK1, PDK1, and the PDK1 target PKCι in the intestine. Surprisingly, tamoxifen-treated cSGK1/MYO5B-DKO mice displayed more severe diarrhea than cMYO5BKO, with preservation of apical CFTR and CHE cells, greater fecal glucose and reduced SGLT1 and GLUT2 in the intestine. We conclude that loss of SGK1 worsens carbohydrate malabsorption and diarrhea in MVID.

11.
Mol Biol Cell ; 32(8): 690-702, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33596087

RESUMEN

Par1b/MARK2 is a Ser/Thr kinase with pleiotropic effects that participates in the generation of apico-basal polarity in Caenorhabditis elegans. It is phosphorylated by atypical PKC(ι/λ) in Thr595 and inhibited. Because previous work showed a decrease in atypical protein kinase C (aPKC) activity under proinflammatory conditions, we analyzed the hypothesis that the resulting decrease in Thr595-MARK2 with increased kinase activity may also participate in innate immunity. We confirmed that pT595-MARK2 was decreased under inflammatory stimulation. The increase in MARK2 activity was verified by Par3 delocalization and rescue with a specific inhibitor. MARK2 overexpression significantly enhanced the transcriptional activity of NF-kB for a subset of transcripts. It also resulted in phosphorylation of a single band (∼Mr 80,000) coimmunoprecipitating with RelA, identified as Med17. In vitro phosphorylation showed direct phosphorylation of Med17 in Ser152 by recombinant MARK2. Expression of S152D-Med17 mimicked the effect of MARK2 activation on downstream transcriptional regulation, which was antagonized by S152A-Med17. The decrease in pThr595 phosphorylation was validated in aPKC-deficient mouse jejunal mucosae. The transcriptional effects were confirmed in transcriptome analysis and transcript enrichment determinations in cells expressing S152D-Med17. We conclude that theMARK2-Med17 axis represents a novel form of cross-talk between polarity signaling and transcriptional regulation including, but not restricted to, innate immunity responses.


Asunto(s)
Polaridad Celular/fisiología , Complejo Mediador/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Expresión Génica/genética , Regulación de la Expresión Génica/genética , Humanos , Inmunidad Innata/fisiología , Complejo Mediador/fisiología , Ratones , FN-kappa B/metabolismo , Fosforilación , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Proteínas Serina-Treonina Quinasas/fisiología , Transducción de Señal
12.
J Control Release ; 334: 389-412, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-33964364

RESUMEN

Nanobodies (Nb) have a promising future as a part of next generation chemodrug delivery systems. Nb, or VHH, are small (15 kDa) monomeric antibody fragments consisting of the antigen binding region of heavy chain antibodies. Heavy chain antibodies are naturally produced by camelids, however the structure of their VHH regions can be readily reproduced in industrial expression systems, such as bacteria or yeast. Due to their small size, high solubility, remarkable stability, manipulatable characteristics, excellent in vivo tissue penetration, conjugation advantages, and ease of production, Nb have many advantages when compared against their antibody precursors. In this review, we discuss the generation and selection of Nbs via phage display libraries for easy screening, and the conjugation techniques involved in creating target-specific nanocarriers. Furthermore, we provide a comprehensive overview of recent developments and perspectives in the field of Nb drug conjugates (NDCs) and Nb-based drug vehicles (NDv) with respect to antitumor therapeutics.


Asunto(s)
Anticuerpos de Dominio Único , Anticuerpos , Portadores de Fármacos , Fragmentos de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina
13.
J Cell Biochem ; 111(3): 643-52, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-20589763

RESUMEN

In several human cancers, ErbB2 over-expression facilitates the formation of constitutively active homodimers resistant to internalization which results in progressive signal amplification from the receptor, conducive to cell survival, proliferation, or metastasis. Here we report on studies of the influence of ErbB2 over-expression on localization and signaling in polarized Caco-2 and MDCK cells, two established models to study molecular trafficking. In these cells, ErbB2 is not over-expressed and shares basolateral localization with ErbB3. Over-expression of ErbB2 by transient transfection resulted in partial separation of the receptors by relocalization of ErbB2, but not ErbB3, to the apical surface, as shown by biotinylation of the apical or basolateral surfaces. These results were confirmed by immunofluorescence and confocal microscopy. Polarity controls indicated that the relocalization of ErbB2 is not the result of depolarization of the cells. Biotinylation and confocal microscopy also showed that apical, but not basolateral ErbB2 is activated at tyrosine 1139. This phosphotyrosine binds adaptor protein Grb2, as confirmed by immunoprecipitation. However, we found that it does not initiate the canonical Grb2-Ras-Raf-Erk pathway. Instead, our data supports the activation of a survival pathway via Bcl-2. The effects of ErbB2 over-expression were abrogated by the humanized anti-ErbB2 monoclonal antibody Herceptin added only from the apical side. The ability of apical ErbB2 to initiate an altered downstream cascade suggests that subcellular localization of the receptor plays an important role in regulating ErbB2 signaling in polarized epithelia.


Asunto(s)
Polaridad Celular , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Transducción de Señal , Animales , Células CACO-2 , Línea Celular , Supervivencia Celular , Perros , Expresión Génica , Humanos , Transporte de Proteínas , Proteínas Proto-Oncogénicas c-bcl-2 , Receptor ErbB-2/farmacología
14.
Mol Biol Cell ; 18(3): 781-94, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17182859

RESUMEN

In simple epithelial cells, attachment of microtubule-organizing centers (MTOCs) to intermediate filaments (IFs) enables their localization to the apical domain. It is released by cyclin-dependent kinase (Cdk)1 phosphorylation. Here, we identified a component of the gamma-tubulin ring complex, gamma-tubulin complex protein (GCP)6, as a keratin partner in yeast two-hybrid assays. This was validated by binding in vitro of both purified full-length HIS-tagged GCP6 and a GCP6(1397-1819) fragment to keratins, and pull-down with native IFs. Keratin binding was blocked by Cdk1-mediated phosphorylation of GCP6. GCP6 was apical in normal enterocytes but diffuse in K8-null cells. GCP6 knockdown with short hairpin RNAs (shRNAs) in CACO-2 cells resulted in gamma-tubulin signal scattered throughout the cytoplasm, microtubules (MTs) in the perinuclear and basal regions, and microtubule-nucleating activity localized deep in the cytoplasm. Expression of a small fragment GCP6(1397-1513) that competes binding to keratins in vitro displaced gamma-tubulin from the cytoskeleton and resulted in depolarization of gamma-tubulin and changes in the distribution of microtubules and microtubule nucleation sites. Expression of a full-length S1397D mutant in the Cdk1 phosphorylation site delocalized centrosomes. We conclude that GCP6 participates in the attachment of MTOCs to IFs in epithelial cells and is among the factors that determine the peculiar architecture of microtubules in polarized epithelia.


Asunto(s)
Células Epiteliales/metabolismo , Filamentos Intermedios/metabolismo , Queratinas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Animales , Proteína Quinasa CDC2/metabolismo , Células COS , Polaridad Celular , Chlorocebus aethiops , Regulación hacia Abajo/genética , Células Epiteliales/citología , Histonas/genética , Humanos , Ratones , Proteínas Asociadas a Microtúbulos/genética , Centro Organizador de los Microtúbulos/metabolismo , Mutación/genética , Fosforilación , Regiones Promotoras Genéticas/genética , Unión Proteica , Transporte de Proteínas , ARN Interferente Pequeño/metabolismo , Transcripción Genética , Tubulina (Proteína)/metabolismo
15.
Talanta ; 218: 121138, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32797895

RESUMEN

Herein, we report the simple and inexpensive approach for the large-scale fabrication of uniform bottom-up Surface Enhanced Raman Spectroscopy (SERS) substrate. SERS substrate was fabricated by controlled sputtering of 10 nm thick gold film on self-assembled silica nanoparticles (SiNPs) of ~120 nm on glass substrates. The SERS detection has been firstly demonstrated using Rhodamine B as a Raman probe molecule with a detection limit of 10-10 M on Au sputtered SiNPs (i.e., Au@SiNPs). The experimental Raman enhancement from 0 to 6 was achieved on Au@SiNPs due to the generation of multiple SERS hotspot. To combat blood serum fouling, the zwitterionic modification of l-cysteine was done on Au@SiNPs substrates which lowered blood serum fouling by 48%. Our SERS-based sensor demonstrated high reproducibility for the detection of Doxorubicin in undiluted blood serum with a limit of detection of 20 nM, which greatly exceeded the detection range of available methodologies. We envision that the translation of this SERS substrate for the detection of chemo-drugs like Doxorubicin will assist clinicians in making rapid and/or early decisions in patients undergoing sustained chemotherapy to lower its side-effects or to incorporate other treatment methodologies as an option for Personalized treatment.


Asunto(s)
Nanopartículas del Metal , Doxorrubicina , Monitoreo de Drogas , Oro , Humanos , Reproducibilidad de los Resultados , Suero , Espectrometría Raman
16.
Rev Esp Salud Publica ; 942020 Dec 16.
Artículo en Español | MEDLINE | ID: mdl-33323920

RESUMEN

OBJECTIVE: The main justification of this study was to describe our experience in neonatal screening and to define the prevalence of the diseases included in the neonatal screening program in Andalusia, among which are congenital hypothyroidism, expanded screening (aminoacidopathies, mitochondrial beta-oxidation defects and organic acidurias), cystic fibrosis, and screening for sickle cell anemia. METHODS: The study was carried out in the Metabolopathies Unit of the Virgen del Rocío Hospital in Seville with samples of newborns from Western Andalusia (Cádiz, Córdoba, Huelva and Seville) and autonomous city of Ceuta. A total of 435,141 newborns were studied (from the period from April 1st 2009 to December 31st 2019) to rule out congenital hypothyroidism and expanded screening; 378,306 for cystic fibrosis from May 1st 2011 to the same date described above. Finally, sickle cell anemia screening was included, which comprised a total of 55,576 newborns from November 26th, 2018 to the same period as the previous ones. Statistical analysis was performed using IBM SPSS software (version 22, SPSS INC., USA). RESULTS: The study revealed a prevalence of 1:1565 newborns for congenital hypothyroidism, 1:1532 newborns for extended screening, 1:6.878 newborns for cystic fibrosis, and a 1:11.115 newborns for sickle cell disease. CONCLUSIONS: The neonatal screening program allows a large number of newborns to benefit from the early detection of certain serious congenital diseases. This aim improves the morbidity and mortality of those who suffer from them.


OBJETIVO: La principal justificación del trabajo fue describir nuestra experiencia en cribado neonatal y definir la prevalencia de cada una de las enfermedades incluidas en el programa de cribado neonatal de Andalucía, entre las que se encuentran el hipotiroidismo congénito, cribado ampliado expandido (aminoacidopatías, defectos de la beta-oxidación mitocondrial y acidurias orgánicas), fibrosis quística y enfermedad de células falciformes. METODOS: El estudio se realizó en la Unidad del Laboratorio de Metabolopatías del Hospital Universitario Virgen del Rocío de Sevilla con muestras de recién nacidos de Andalucía Occidental (Cádiz, Córdoba, Huelva y Sevilla) y la ciudad autónoma de Ceuta. Para descartar hipotiroidismo congénito y cribado ampliado expandido se estudiaron un total de 435.141 recién nacidos, con fecha de inicio el 1 de abril de 2009. El cribado de fibrosis quística comenzó el 1 de mayo de 2011, siendo estudiados un total de 378.306 recién nacidos. Por último, el 26 de noviembre de 2018 se incorporó el cribado de anemia de células falciformes, que comprendió un total de 55.576 recién nacidos. La fecha fin de estudio fue el 31 de diciembre de 2019 para todas las patologías descritas anteriormente. El análisis estadístico se realizó usando el software IBM SPSS (versión 22, SPSS INC., EEUU). RESULTADOS: El estudio reveló una prevalencia de 1:1.565 recién nacidos para hipotiroidismo congénito, 1:1.532 para cribado ampliado expandido, 1:6.878 para fibrosis quística y 1:11.115 recién nacidos para enfermedad de células falciformes. CONCLUSIONES: El programa de cribado neonatal permite que se beneficien gran número de recién nacidos en la detección precoz de determinadas enfermedades congénitas graves y, con ello, mejora la morbimortalidad de aquellos que las padecen.


Asunto(s)
Anemia de Células Falciformes/diagnóstico , Hipotiroidismo Congénito/diagnóstico , Fibrosis Quística/diagnóstico , Errores Innatos del Metabolismo/diagnóstico , Tamizaje Neonatal , Anemia de Células Falciformes/epidemiología , Hipotiroidismo Congénito/epidemiología , Fibrosis Quística/epidemiología , Diagnóstico Precoz , Humanos , Recién Nacido , Estudios Longitudinales , Errores Innatos del Metabolismo/epidemiología , Prevalencia , Estudios Retrospectivos , España/epidemiología
17.
Rev Esp Salud Publica ; 942020 Dec 16.
Artículo en Español | MEDLINE | ID: mdl-33372917

RESUMEN

OBJECTIVE: Tandem mass spectrometry (MS/MS) is being used for newborn screening since this laboratory testing technology increases the number of metabolic disorders that can be detected from dried blood-spot specimens. In the Community of Madrid, it was implemented in March 2011 and it includes 13 aminoacidopathies, fatty acid oxidation disorders and organic acidemias. The aim of this study was to describe our experience and evaluate the screening positive cases in a period of 9 years (2011-2019). METHODS: During the period of the study, a total of 592.822 neonates were screened with this expanded program by MS/MS in the Community of Madrid. Amino acids, acylcarnitines, and succinylacetone were quantified in all samples that met the quality criteria. Means, medians, percentiles and standard deviation of the analytes and ratios of interest were calculated. RESULTS: 901 patients (0,15 %) with a positive screening test were referred to clinical evaluation. 230 patients were diagnosed of 30 different inborn errors of metabolism (prevalence 1:2577), 11 of which were not included as a target in the Community of Madrid newborn screening program. The global positive predictive value was 25,6 %. During this period of time, two false negative cases were detected. The most prevalent disorders were phenylketonuria/hyperphenylalaninemia and medium chain acyl-CoA dehydrogenase deficiency (1:6444 and 1:13174 respectively). 93 % of the patients were detected in the presymptomatic stage. CONCLUSIONS: During the last 9 years a large number of cases of IEM have been detected with an acceptable global positive predictive value. These results confirm the utility of inborn errors of metabolism newborn screening as a public health program.


OBJETIVO: La tecnología de espectrometría de masas en tándem (MS/MS) en los programas de cribado neonatal ha permitido la detección de gran número de errores congénitos del metabolismo (ECM). En la comunidad de Madrid se implementó en marzo de 2011 incluyendo 13 aminoacidopatías, defectos de la ß-oxidación de ácidos grasos y acidemias orgánicas. El objetivo de este estudio fue describir nuestra experiencia y analizar los casos positivos de cribado en un periodo de 9 años (2011-2019). METODOS: Durante el periodo de estudio se realizó el cribado mediante MS/MS a 592822 recién nacidos en la Comunidad de Madrid. Se cuantificaron aminoácidos, acilcarnitinas y succinilacetona en todas las muestras que cumplieron los criterios de calidad. Se calcularon medias, medianas, percentiles y desviación típica de los analitos y ratios de interés. RESULTADOS: Se derivaron a las unidades clínicas de seguimiento por sospecha de una ECM un total de 901 (0,15 %) casos. Se confirmaron 230 casos de 30 ECM diferentes (prevalencia 1:2577), 11 de los cuales no eran inicialmente objetivo de detección del programa. El valor predictivo positivo global fue de 25,6 %. Durante este periodo se detectaron dos falsos negativos. Las enfermedades con mayor prevalencia fueron fenilcetonuria/hiperfenilalaninemia y deficiencia de acil-CoA deshidrogenasa de cadena media (1:6444 y 1: 13174 respectivamente). 93 % de los casos fueron detectados en fase presintomática. CONCLUSIONES: En estos 9 años de experiencia se han detectado numerosos casos de ECM con un valor predictivo positivo global aceptable. Estos resultados confirman la utilidad del cribado neonatal de ECM como programa de salud pública.


Asunto(s)
Acil-CoA Deshidrogenasa/deficiencia , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Errores Innatos del Metabolismo Lipídico/diagnóstico , Tamizaje Neonatal/métodos , Espectrometría de Masas en Tándem/métodos , Errores Innatos del Metabolismo de los Aminoácidos/epidemiología , Carnitina/análogos & derivados , Carnitina/sangre , Ciudades , Femenino , Humanos , Recién Nacido , Errores Innatos del Metabolismo Lipídico/epidemiología , Masculino , Valor Predictivo de las Pruebas , Prevalencia , España
18.
Exp Eye Res ; 88(1): 99-105, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19013153

RESUMEN

Development of immortalized mouse retinal pigmented epithelial cell (RPE) lines that retain many of their in vivo phenotypic characteristics, would aid in studies of ocular diseases including age related macular degeneration (AMD). RPE cells were isolated from 18-month-old (estrogen receptor knockout) ERKOalpha and ERKObeta mice and their C57Bl/6 wildtype littermates. RPE65 and cellular retinaldehyde binding protein (CRALBP) expression, in vivo markers of RPE cells, were detected by real-time RT-PCR and western analysis. We confirmed the presence of epithelial cell markers, ZO1, cytokeratin 8 and 18 by immunofluorescence staining. In addition, we confirmed the distribution of actin filaments and the expression of ezrin. To develop cell lines, RPE cells were isolated, propagated and immortalized using human papilloma virus (HPV) 16 (E6/E7). RPE-specific markers and morphology were assessed before and after immortalization. In wildtype littermate controls, there was no evidence of any alterations in the parameters that we examined including MMP-2, TIMP-2, collagen type IV, and estrogen receptor (ER)alpha and ERbeta protein expression and ER copy number ratio. Therefore, immortalized mouse RPE cell lines that retain their in vivo phenotype can be isolated from either pharmacologically or genetically manipulated mice, and may be used to study RPE cell biology.


Asunto(s)
Transformación Celular Viral , Epitelio Pigmentado de la Retina/citología , Animales , Western Blotting , Proteínas Portadoras/metabolismo , División Celular/fisiología , Línea Celular Transformada , Polaridad Celular/fisiología , Supervivencia Celular/fisiología , Proteínas del Ojo/metabolismo , Femenino , Papillomavirus Humano 16 , Uniones Intercelulares/metabolismo , Uniones Intercelulares/ultraestructura , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Receptores de Estrógenos/deficiencia , Receptores de Estrógenos/genética , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/ultraestructura , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Transfección , cis-trans-Isomerasas
19.
Mol Biol Cell ; 17(7): 2931-41, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16624867

RESUMEN

Muc4 serves as an intramembrane ligand for the receptor tyrosine kinase ErbB2. The time to complex formation and the stoichiometry of the complex were determined to be <15 min and 1:1 by analyses of Muc4 and ErbB2 coexpressed in insect cells and A375 tumor cells. In polarized CACO-2 cells, Muc4 expression causes relocalization of ErbB2, but not its heterodimerization partner ErbB3, to the apical cell surface, effectively segregating the two receptors. The apically located ErbB2 is phosphorylated on tyrosines 1139 and 1248. The phosphorylated ErbB2 in CACO-2 cells recruits the cytoplasmic adaptor protein Grb2, consistent with previous studies showing phosphotyrosine 1139 to be a Grb2 binding site. To address the issue of downstream signaling from apical ErbB2, we analyzed the three MAPK pathways of mammalian cells, Erk, p38, and JNK. Consistent with the more differentiated phenotype of the CACO-2 cells, p38 phosphorylation was robustly increased by Muc4 expression, with a consequent activation of Akt. In contrast, Erk and JNK phosphorylation was not changed. The ability of Muc4 to segregate ErbB2 and other ErbB receptors and to alter downstream signaling cascades in polarized epithelial cells suggests that it has a role in regulating ErbB2 in differentiated epithelia.


Asunto(s)
Diferenciación Celular , Células Epiteliales/citología , Mucinas/metabolismo , Receptor ErbB-2/metabolismo , Sitios de Unión , Células CACO-2 , Polaridad Celular , Citoplasma/química , Citoplasma/metabolismo , Activación Enzimática , Células Epiteliales/química , Células Epiteliales/metabolismo , Proteína Adaptadora GRB2/metabolismo , Humanos , Ligandos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mucina 4 , Mucinas/análisis , Fosforilación , Receptor ErbB-2/análisis , Transducción de Señal , Tirosina/metabolismo
20.
Mol Biol Cell ; 30(26): 3076-3089, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31664880

RESUMEN

Loss-of-function mutations in the nonconventional myosin Vb (Myo5b) result in microvillus inclusion disease (MVID) and massive secretory diarrhea that often begins at birth. Myo5b mutations disrupt the apical recycling endosome (ARE) and membrane traffic, resulting in reduced surface expression of apical membrane proteins. ARE disruption also results in constitutive phosphoinositide-dependent kinase 1 gain of function. In MVID, decreased surface expression of apical anion channels involved in Cl- extrusion, such as cystic fibrosis transmembrane conductance regulator (CFTR), should reduce fluid secretion into the intestinal lumen. But the opposite phenotype is observed. To explain this contradiction and the onset of diarrhea, we hypothesized that signaling effects downstream from Myo5b loss of function synergize with higher levels of glucocorticoids to activate PKA and CFTR. Data from intestinal cell lines, human MVID, and Myo5b KO mouse intestine revealed changes in the subcellular redistribution of PKA activity to the apical pole, increased CFTR phosphorylation, and establishment of apical cAMP gradients in Myo5b-defective cells exposed to physiological levels of glucocorticoids. These cells also displayed net secretory fluid fluxes and transepithelial currents mainly from PKA-dependent Cl- secretion. We conclude that Myo5b defects result in PKA stimulation that activates residual channels on the surface when intestinal epithelia are exposed to glucocorticoids at birth.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Glucocorticoides/metabolismo , Miosina Tipo V/genética , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Animales , Células CACO-2 , Línea Celular Tumoral , Canales de Cloruro/metabolismo , Diarrea/congénito , Diarrea/genética , Humanos , Síndromes de Malabsorción/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Microvellosidades/genética , Microvellosidades/patología , Mucolipidosis/genética
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