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1.
EMBO J ; 42(23): e113714, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37916875

RESUMEN

Primary Sjögren's syndrome (pSS) is an inflammatory autoimmune disorder largely mediated by type I and II interferon (IFN). The potential contribution of innate immune cells, such as natural killer (NK) cells and dendritic cells (DC), to the pSS pathology remains understudied. Here, we identified an enriched CD16+ CD56hi NK cell subset associated with higher cytotoxic function, as well as elevated proportions of inflammatory CD64+ conventional dendritic cell (cDC2) subtype that expresses increased levels of MICa/b, the ligand for the activating receptor NKG2D, in pSS individuals. Circulating cDC2 from pSS patients efficiently induced activation of cytotoxic NK cells ex vivo and were found in proximity to CD56+ NK cells in salivary glands (SG) from pSS patients. Interestingly, transcriptional activation of IFN signatures associated with the RIG-I/DDX60 pathway, IFN I receptor, and its target genes regulate the expression of NKG2D ligands on cDC2 from pSS patients. Finally, increased proportions of CD64hi RAE-1+ cDC2 and NKG2D+ CD11b+ CD27+ NK cells were present in vivo in the SG after poly I:C injection. Our study provides novel insight into the contribution and interplay of NK and cDC2 in pSS pathology and identifies new potential therapy targets.


Asunto(s)
Autoinmunidad , Subfamilia K de Receptores Similares a Lectina de Células NK , Humanos , Subfamilia K de Receptores Similares a Lectina de Células NK/genética , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Células Asesinas Naturales , Células Dendríticas
2.
Mol Microbiol ; 121(3): 359-367, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37740453

RESUMEN

Apicomplexans, such as Plasmodium and Toxoplasma are obligate intracellular parasites that invade, replicate and finally EXIT their host cell. During replication within a parasitophorous vacuole (PV), the parasites establish an extensive F-actin-containing network that connects individual parasites and is required for material exchange, recycling and the final steps of daughter cell assembly. After multiple rounds of replication, the parasites exit the host cell involving multiple signalling cascades, disassembly of the network, secretion of microneme proteins and activation of the acto-myosin motor. Blocking the host cell EXIT process leads to the formation of large PVs, making the screening for genes involved in exiting the cell relatively straightforward. Given that apicomplexans are highly diverse from other eukaryotes, approximately 30% of all genes are annotated as hypothetical, some apicomplexan-specific factors are likely to be critical during EXIT. This motivated several labs to design and perform forward genetic and phenotypic screens using various approaches, such as random insertion mutagenesis, temperature-sensitive mutants and, more recently, CRISPR/Cas9-mediated targeted editing and conditional mutagenesis. Here we will provide an overview of the technological developments over recent years and the most successful stories that led to the identification of new critical factors in Toxoplasma gondii.


Asunto(s)
Parásitos , Plasmodium , Toxoplasma , Animales , Parásitos/metabolismo , Toxoplasma/metabolismo , Plasmodium/metabolismo , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo
3.
J Cell Sci ; 136(21)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37815466

RESUMEN

Connections between the nucleus and the cytoskeleton are important for positioning and division of the nucleus. In most eukaryotes, the linker of nucleoskeleton and cytoskeleton (LINC) complex spans the outer and inner nuclear membranes and connects the nucleus to the cytoskeleton. In opisthokonts, it is composed of Klarsicht, ANC-1 and Syne homology (KASH) domain proteins and Sad1 and UNC-84 (SUN) domain proteins. Given that the nucleus is positioned at the posterior pole of Toxoplasma gondii, we speculated that apicomplexan parasites must have a similar mechanism that integrates the nucleus and the cytoskeleton. Here, we identified three UNC family proteins in the genome of the apicomplexan parasite T. gondii. Whereas the UNC-50 protein TgUNC1 localised to the Golgi and appeared to be not essential for the parasite, the SUN domain protein TgSLP2 showed a diffuse pattern throughout the parasite. The second SUN domain protein, TgSLP1, was expressed in a cell cycle-dependent manner and was localised close to the mitotic spindle and, more detailed, at the kinetochore. We demonstrate that conditional knockout of TgSLP1 leads to failure of nuclear division and loss of centrocone integrity.


Asunto(s)
Parásitos , Toxoplasma , Animales , Toxoplasma/genética , Membrana Nuclear/metabolismo , Huso Acromático , División del Núcleo Celular
4.
Cell Mol Life Sci ; 81(1): 199, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38683377

RESUMEN

Tyrosine kinase 2 (TYK2) is involved in type I interferon (IFN-I) signaling through IFN receptor 1 (IFNAR1). This signaling pathway is crucial in the early antiviral response and remains incompletely understood on B cells. Therefore, to understand the role of TYK2 in B cells, we studied these cells under homeostatic conditions and following in vitro activation using Tyk2-deficient (Tyk2-/-) mice. Splenic B cell subpopulations were altered in Tyk2-/- compared to wild type (WT) mice. Marginal zone (MZ) cells were decreased and aged B cells (ABC) were increased, whereas follicular (FO) cells remained unchanged. Likewise, there was an imbalance in transitional B cells in juvenile Tyk2-/- mice. RNA sequencing analysis of adult MZ and FO cells isolated from Tyk2-/- and WT mice in homeostasis revealed altered expression of IFN-I and Toll-like receptor 7 (TLR7) signaling pathway genes. Flow cytometry assays corroborated a lower expression of TLR7 in MZ B cells from Tyk2-/- mice. Splenic B cell cultures showed reduced proliferation and differentiation responses after activation with TLR7 ligands in Tyk2-/- compared to WT mice, with a similar response to lipopolysaccharide (LPS) or anti-CD40 + IL-4. IgM, IgG, IL-10 and IL-6 secretion was also decreased in Tyk2-/- B cell cultures. This reduced response of the TLR7 pathway in Tyk2-/- mice was partially restored by IFNα addition. In conclusion, there is a crosstalk between TYK2 and TLR7 mediated by an IFN-I feedback loop, which contributes to the establishment of MZ B cells and to B cell proliferation and differentiation.


Asunto(s)
Linfocitos B , Interferón Tipo I , Transducción de Señal , Bazo , TYK2 Quinasa , Receptor Toll-Like 7 , Animales , Ratones , Linfocitos B/metabolismo , Linfocitos B/inmunología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Interferón Tipo I/metabolismo , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Bazo/citología , Bazo/metabolismo , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 7/genética , TYK2 Quinasa/metabolismo , TYK2 Quinasa/genética
5.
Eur J Neurol ; 31(4): e16184, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38095330

RESUMEN

BACKGROUND AND PURPOSE: Post-stroke aphasia is associated with a reduced quality of life (QoL) and higher risk of depression. Few studies have addressed the effect of coping with aphasia. Our aim is to evaluate the impact of post-stroke aphasia on self-reported QoL and symptoms of depression. METHODS: This was a cross-sectional prospective case-control study. Cases involved patients with post-stroke aphasia included in the DULCINEA trial (NCT04289493). Healthy controls were recruited using snowball sampling. All subjects completed the following questionnaires: General Health Questionnaire (GHQ-12), Stroke Aphasia Quality of Life Scale (SAQOL-39), Communicative Activity Log (CAL) and Stroke Aphasic Depression Questionnaire (SADQ-10). RESULTS: Twenty-three patients (eight women; mean age 62.9 years) and 73 controls (42 women; mean age 53.7 years) were included. Cases scored lower than controls in perception of health (GHQ-12: median 3 [IQR 1; 6] vs. 0 [IQR 0; 2]) and perception of QoL (SAQOL-39: median 3.6 [IQR 3.3; 40] vs. 4.6 [IQR 4.2; 4.8]). Functional communication (CAL: median 135 [IQR 122; 148] vs. 94 [IQR 74; 103]) and SAQOL-39 communication subscale (median 2.7 [IQR 2.1; 3.2] vs. 4.8 [IQR 4.6; 5.0]) were also significantly lower in the case group. Notably, cases reported fewer depressive symptoms than controls (SADQ-10: median 11 [IQR 9; 15] vs. 13 [IQR 11; 16]; p = 0.016). A mediational analysis revealed that the relationship between post-stroke aphasia and depression was not mediated by functional communication. CONCLUSIONS: Although communication difficulties impact the QoL of patients with post-stroke aphasia, such patients report fewer depressive symptoms on the SADQ-10 scale than healthy people, with no differences in scores related to social participation.


Asunto(s)
Afasia , Calidad de Vida , Humanos , Femenino , Persona de Mediana Edad , Estudios de Casos y Controles , Depresión , Estudios Transversales , Encuestas y Cuestionarios , Comunicación , Percepción
6.
Inorg Chem ; 63(19): 8642-8653, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38690944

RESUMEN

The synthesis, structure, and catalytic activity of a Ti(II)/Ti(III) inverted sandwich compound are presented in this study. Synthesis of the arene-bridged dititanium compound begins with the preparation of the titanium(IV) precursor [TiCl2(MesPDA)(thf)2] (MesPDA = N,N'-bis(2,4,6-trimethylphenyl)-o-phenylenediamide) (2). The reduction of 2 with sodium metal results in species [{Ti(MesPDA)(thf)}2(µ-Cl)3{Na}] (3) in oxidation state III. To achieve the lower oxidation state II, 2 undergoes reduction through alkylation with lithium cyclopentyl. This alkylation approach triggers a cascade of reactions, including ß-hydride abstraction/elimination, hydrogen evolution, and chemical reduction, to generate the Ti(II)/Ti(III) compound [Li(thf)4][(TiMesPDA)2(µ-η6: η6-C6H6)] (4). X-ray and EPR characterization confirms the mixed-valence states of the titanium species. Compound 4 catalyzes a mild, efficient, and regiospecific cyclotrimerization of alkynes to form 1,3,5-substituted arenes. Kinetic data support a mechanism involving a binuclear titanium arene compound, similar to compound 4, as the resting state. The active catalyst promotes the oxidative coupling of two alkynes in the rate-limiting step, followed by a rapid [4 + 2] cycloaddition to form the arene product. Computational analysis of the resting state for the cycloaddition of trimethylsilylacetylene indicates a thermodynamic preference for stabilizing the 1,3,5-arene within the space between the two [TiMesPDA] fragments, consistent with the observed regioselectivity.

7.
Med Res Rev ; 42(5): 1978-2001, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35707911

RESUMEN

The complexity of the tumor microenvironment (TME) together with the development of the metastatic process are the main reasons for the failure of conventional anticancer treatment. In recent years, there is an increasing need to advance toward advanced in vitro models of cancer mimicking TME and simulating metastasis to understand the associated mechanisms that are still unknown, and to be able to develop personalized therapy. In this review, the commonly used alternatives and latest advances in biofabrication of tumor-on-chips, which allow the generation of the most sophisticated and optimized models for recapitulating the tumor process, are presented. In addition, the advances that have allowed these new models in the area of metastasis, cancer stem cells, and angiogenesis are summarized, as well as the recent integration of multiorgan-on-a-chip systems to recapitulate natural metastasis and pharmacological screening against it. We also analyze, for the first time in the literature, the normative and regulatory framework in which these models could potentially be found, as well as the requirements and processes that must be fulfilled to be commercially implemented as in vitro study model. Moreover, we are focused on the possible regulatory pathways for their clinical application in precision medicine and decision making through the generation of personalized models with patient samples. In conclusion, this review highlights the synergistic combination of three-dimensional bioprinting systems with the novel tumor/metastasis/multiorgan-on-a-chip systems to generate models for both basic research and clinical applications to have devices useful for personalized oncology.


Asunto(s)
Bioimpresión , Neoplasias , Bioimpresión/métodos , Humanos , Dispositivos Laboratorio en un Chip , Neoplasias/tratamiento farmacológico , Medicina de Precisión/métodos , Microambiente Tumoral
8.
PLoS Med ; 19(4): e1003980, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35476675

RESUMEN

BACKGROUND: We previously found that 25% of 1,017 randomized clinical trials (RCTs) approved between 2000 and 2003 were discontinued prematurely, and 44% remained unpublished at a median of 12 years follow-up. We aimed to assess a decade later (1) whether rates of completion and publication have increased; (2) the extent to which nonpublished RCTs can be identified in trial registries; and (3) the association between reporting quality of protocols and premature discontinuation or nonpublication of RCTs. METHODS AND FINDINGS: We included 326 RCT protocols approved in 2012 by research ethics committees in Switzerland, the United Kingdom, Germany, and Canada in this metaresearch study. Pilot, feasibility, and phase 1 studies were excluded. We extracted trial characteristics from each study protocol and systematically searched for corresponding trial registration (if not reported in the protocol) and full text publications until February 2022. For trial registrations, we searched the (i) World Health Organization: International Clinical Trial Registry Platform (ICTRP); (ii) US National Library of Medicine (ClinicalTrials.gov); (iii) European Union Drug Regulating Authorities Clinical Trials Database (EUCTR); (iv) ISRCTN registry; and (v) Google. For full text publications, we searched PubMed, Google Scholar, and Scopus. We recorded whether RCTs were registered, discontinued (including reason for discontinuation), and published. The reporting quality of RCT protocols was assessed with the 33-item SPIRIT checklist. We used multivariable logistic regression to examine the association between the independent variables protocol reporting quality, planned sample size, type of control (placebo versus other), reporting of any recruitment projection, single-center versus multicenter trials, and industry versus investigator sponsoring, with the 2 dependent variables: (1) publication of RCT results; and (2) trial discontinuation due to poor recruitment. Of the 326 included trials, 19 (6%) were unregistered. Ninety-eight trials (30%) were discontinued prematurely, most often due to poor recruitment (37%; 36/98). One in 5 trials (21%; 70/326) remained unpublished at 10 years follow-up, and 21% of unpublished trials (15/70) were unregistered. Twenty-three of 147 investigator-sponsored trials (16%) reported their results in a trial registry in contrast to 150 of 179 industry-sponsored trials (84%). The median proportion of reported SPIRIT items in included RCT protocols was 69% (interquartile range 61% to 77%). We found no variables associated with trial discontinuation; however, lower reporting quality of trial protocols was associated with nonpublication (odds ratio, 0.71 for each 10% increment in the proportion of SPIRIT items met; 95% confidence interval, 0.55 to 0.92; p = 0.009). Study limitations include that the moderate sample size may have limited the ability of our regression models to identify significant associations. CONCLUSIONS: We have observed that rates of premature trial discontinuation have not changed in the past decade. Nonpublication of RCTs has declined but remains common; 21% of unpublished trials could not be identified in registries. Only 16% of investigator-sponsored trials reported results in a trial registry. Higher reporting quality of RCT protocols was associated with publication of results. Further efforts from all stakeholders are needed to improve efficiency and transparency of clinical research.


Asunto(s)
Investigadores , Alemania , Humanos , Oportunidad Relativa , Ensayos Clínicos Controlados Aleatorios como Asunto , Sistema de Registros
9.
Anal Chem ; 94(25): 8919-8927, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35687534

RESUMEN

Medical diagnostics is moving toward disease-related target detection at very low concentrations because of the (1) quest for early-stage diagnosis, at a point where only limited target amounts are present, (2) trend toward minimally invasive sample extraction, yielding samples containing low concentrations of target, and (3) need for straightforward sample collection, usually resulting in limited volume collected. Hence, diagnostic tools allowing ultrasensitive target detection at the point-of-care (POC) are crucial for simplified and timely diagnosis of many illnesses. Therefore, we developed an innovative, fully integrated, semi-automated, and economically viable platform based on (1) digital microfluidics (DMF), enabling automated manipulation and analysis of very low sample volumes and (2) low-cost disposable DMF chips with microwell arrays, fabricated via roll-to-roll processes and allowing digital target counting. Thyroid stimulating hormone detection was chosen as a relevant application to show the potential of the system. The assay buffer was selected using design of experiments, and the assay was optimized in terms of reagent concentration and incubation time toward maximum sensitivity. The hydrophobic-in-hydrophobic microwells showed an unparalleled seeding efficiency of 97.6% ± 0.6%. A calculated LOD of 0.0013 µIU/mL was obtained, showing the great potential of the platform, especially taking into account the very low sample volume analyzed (1.1 µL). Although validation (in biological matrix) and industrialization (full automation) steps still need to be taken, it is clear that the combination of DMF, low-cost DMF chips, and digital analyte counting in microwell arrays enables the implementation of ultrasensitive and reliable target detection at the POC.


Asunto(s)
Sistemas de Atención de Punto , Tirotropina , Automatización , Bioensayo , Microfluídica/métodos
10.
PLoS Biol ; 17(6): e3000060, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31233488

RESUMEN

Apicomplexan parasites invade host cells in an active process involving their ability to move by gliding motility. While the acto-myosin system of the parasite plays a crucial role in the formation and release of attachment sites during this process, there are still open questions regarding the involvement of other mechanisms in parasite motility. In many eukaryotes, a secretory-endocytic cycle leads to the recycling of receptors (integrins), necessary to form attachment sites, regulation of surface area during motility, and generation of retrograde membrane flow. Here, we demonstrate that endocytosis operates during gliding motility in Toxoplasma gondii and appears to be crucial for the establishment of retrograde membrane flow, because inhibition of endocytosis blocks retrograde flow and motility. We demonstrate that extracellular parasites can efficiently incorporate exogenous material, such as labelled phospholipids, nanogold particles (NGPs), antibodies, and Concanavalin A (ConA). Using labelled phospholipids, we observed that the endocytic and secretory pathways of the parasite converge, and endocytosed lipids are subsequently secreted, demonstrating the operation of an endocytic-secretory cycle. Together our data consolidate previous findings, and we propose an additional model, working in parallel to the acto-myosin motor, that reconciles parasite motility with observations in other eukaryotes: an apicomplexan fountain-flow-model for parasite motility.


Asunto(s)
Movimiento Celular/fisiología , Endocitosis/fisiología , Toxoplasma/metabolismo , Actinas/metabolismo , Animales , Adhesión Celular/fisiología , Extensiones de la Superficie Celular/fisiología , Proteínas de la Membrana/metabolismo , Miosinas/metabolismo , Parásitos , Proteínas Protozoarias/metabolismo , Vías Secretoras/fisiología , Toxoplasma/fisiología
11.
Inorg Chem ; 61(1): 474-485, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34890181

RESUMEN

The reaction of [TaCpRX4] (CpR = η5-C5Me5, η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) with SiH3Ph resulted in the formation of the dinuclear hydride tantalum(IV) compounds [(TaCpRX2)2(µ-H)2], structurally identified by single-crystal X-ray analyses. These species react with azobenzene to give the mononuclear imide complex [TaCpRX2(NPh)] along with the release of molecular hydrogen. Analogous reactions between the [{Ta(η5-C5Me5)X2}2(µ-H)2] derivatives and the cyclic diazo reagent benzo[c]cinnoline afford the biphenyl-bridged (phenylimido)tantalum complexes [{Ta(η5-C5Me5)X2}2(µ-NC6H4C6H4N)] along with the release of molecular hydrogen. When the compounds [(TaCpRX2)2(µ-H)2] (CpR = η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) were employed, we were able to trap the side-on-bound diazo derivatives [(TaCpRX)2{µ-(η2,η2-NC6H4C6H4N)}] (CpR = η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) as intermediates in the N═N bond cleavage process. DFT calculations provide insights into the N═N cleavage mechanism, in which the ditantalum(IV) fragment can promote two-electron reductions of the N═N bond at two different metal-metal bond splitting stages.

12.
Org Biomol Chem ; 20(39): 7787-7794, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36172848

RESUMEN

Novel photoswitches offering features complementary to the well-established azobenzenes are increasingly driving high-precision research in cellular photopharmacology. Styrylthiazolium (StyTz) and styrylbenzothiazolium (StyBtz) are cellularly untested E/Z-isomerisation photoswitches which are nearly isosteric to azobenzenes, but have distinct properties: including ca. 60 nm red-shifted π → π* absorption, self-reporting fluorescence, Z → E relaxation on typical biological timescales, and decent solubility (positive charge). We tested StyTz and StyBtz for their potential as photopharmaceutical scaffolds, by applying them to photocontrol microtubule dynamics. They light-specifically disrupt microtubule network architecture and block cell proliferation: yet, testing lead compound StyBtz2 for its molecular mechanism of action showed that it did not inhibit microtubule dynamics. Using its self-reporting fluorescence, we tracked its localisation in live cells and observed accumulation of E-StyBtz2 into mitochondria; during prolonged illumination, it was released into the cytosol, and blebbing and cell death were observed. We interpret this as light-dependent rupturing of mitochondria on acute timescales. We conclude that StyTz/StyBtz can be interesting photopharmaceutical scaffolds for addressing mitochondrial, rather than cytosolic, targets.


Asunto(s)
Compuestos Azo , Mitocondrias , Compuestos Azo/farmacología , Muerte Celular , Colorantes , Mitocondrias/metabolismo
13.
Eur Arch Psychiatry Clin Neurosci ; 272(1): 5-15, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33811552

RESUMEN

This study aimed to characterize the clinical profile of patients with brief psychotic disorders (BPD) triggered by the psychosocial distress derived from the COVID-19 crisis. A multicenter study was conducted from March 14 to May 14, 2020 (the peak weeks of the pandemic in Europe). All consecutive patients presenting non-affective psychotic episodes with a duration of untreated psychosis of less than 1 month and whose onset was related to the COVID-19 crisis were recruited, but only those patients meeting Diagnostic Statistical Manual 5th edition (DSM-5) criteria for "BPD with marked stressors" (DSM-5 code: 298.8) during follow-up were finally included. Patients' sociodemographic and clinical characteristics were collected at baseline and summarized with descriptive statistics. During the study period, 57 individuals with short-lived psychotic episodes related to the emotional stress of the COVID-19 pandemic were identified, of whom 33 met DSM-5 criteria for "BPD with marked stressors". The mean age was 42.33 ± 14.04 years, the gender distribution was almost the same, and the majority were rated as having good premorbid adjustment. About a quarter of the patients exhibited suicidal symptoms and almost half presented first-rank schizophrenia symptoms. None of them were COVID-19 positive, but in more than half of the cases, the topic of their psychotic features was COVID-19-related. The coronavirus pandemic is triggering a significant number of BPD cases. Their risk of suicidal behavior, their high relapse rate, and their low temporal stability make it necessary to closely monitor these patients over time.


Asunto(s)
COVID-19 , Pandemias , Trastornos Psicóticos , Adulto , COVID-19/epidemiología , COVID-19/psicología , Europa (Continente)/epidemiología , Humanos , Persona de Mediana Edad , Trastornos Psicóticos/epidemiología , Esquizofrenia/epidemiología
14.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35955853

RESUMEN

The increase in cancer incidences shows that there is a need to better understand tumour heterogeneity to achieve efficient treatments. Interestingly, there are several common features among almost all types of cancers, with chronic inflammation induction and deaminase dysfunctions singled out. Deaminases are a family of enzymes with nucleotide-editing capacity, which are classified into two main groups: DNA-based and RNA-based. Remarkably, a close relationship between inflammation and the dysregulation of these molecules has been widely documented, which may explain the characteristic intratumor heterogeneity, both at DNA and transcriptional levels. Indeed, heterogeneity in cancer makes it difficult to establish a unique tumour progression model. Currently, there are three main cancer models-stochastic, hierarchic, and dynamic-although there is no consensus on which one better resembles cancer biology because they are usually overly simplified. Here, to accurately explain tumour progression, we propose interactions among chronic inflammation, deaminases dysregulation, intratumor genetic heterogeneity, cancer phenotypic plasticity, and even the previously proposed appearance of cancer stem-like cell populations in the edges of advanced solid tumour masses (instead of being the cells of origin of primary malignancies). The new tumour development model proposed in this study does not contradict previously accepted models and it may open up a window to interesting therapeutic approaches.


Asunto(s)
Neoplasias , Citidina Desaminasa/genética , ADN/metabolismo , Humanos , Inflamación , Neoplasias/genética , Neoplasias/patología , ARN/metabolismo , Edición de ARN
15.
Int J Mol Sci ; 23(16)2022 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-36012730

RESUMEN

Osteoporosis has been defined as the silent disease of the 21st century, becoming a public health risk due to its severity, chronicity and progression and affecting mainly postmenopausal women and older adults. Osteoporosis is characterized by an imbalance between bone resorption and bone production. It is diagnosed through different methods such as bone densitometry and dual X-rays. The treatment of this pathology focuses on different aspects. On the one hand, pharmacological treatments are characterized by the use of anti-resorptive drugs, as well as emerging regenerative medicine treatments such as cell therapies and the use of bioactive hydrogels. On the other hand, non-pharmacological treatments are associated with lifestyle habits that should be incorporated, such as physical activity, diet and the cessation of harmful habits such as a high consumption of alcohol or smoking. This review seeks to provide an overview of the theoretical basis in relation to bone biology, the existing methods for diagnosis and the treatments of osteoporosis, including the development of new strategies.


Asunto(s)
Resorción Ósea , Osteoporosis Posmenopáusica , Osteoporosis , Anciano , Densidad Ósea , Ejercicio Físico , Femenino , Conductas Relacionadas con la Salud , Humanos , Osteoporosis/tratamiento farmacológico , Osteoporosis/terapia , Fumar
16.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36142235

RESUMEN

Chronic Myeloid Leukemia (CML) originates in a leukemic stem cell that resides in the bone marrow microenvironment, where they coexist with cellular and non-cellular elements. The vascular microenvironment has been identified as an important element in CML development since an increase in the vascularization has been suggested to be related with poor prognosis; also, using murine models, it has been reported that bone marrow endothelium can regulate the quiescence and proliferation of leukemic stem and progenitor cells. This observation, however, has not been evaluated in primary human cells. In this report, we used a co-culture of primitive (progenitor and stem) CML cells with endothelial colony forming cells (ECFC) as an in vitro model to evaluate the effects of the vascular microenvironment in the leukemic hematopoiesis. Our results show that this interaction allows the in vitro maintenance of primitive CML cells through an inflammatory microenvironment able to regulate the proliferation of progenitor cells and the permanence in a quiescent state of leukemic stem cells.


Asunto(s)
Células Endoteliales , Leucemia Mielógena Crónica BCR-ABL Positiva , Animales , Médula Ósea , Enfermedad Crónica , Hematopoyesis , Humanos , Ratones , Células Madre Neoplásicas , Microambiente Tumoral
17.
Gastroenterol Hepatol ; 44(9): 620-627, 2021 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33249114

RESUMEN

BACKGROUND AND AIMS: Transjugular intrahepatic portosystemic shunts (TIPS) are successfully used in the management of portal hypertension (PH)-related complications. Debate surrounds the diameter of the dilation. The aim was to analyse the outcomes of and complications deriving from TIPS in patients with cirrhosis and identify predictors of survival. METHODS: This was a retrospective single-centre study, which included patients with cirrhosis who had a TIPS procedure for PH from 2009 to October 2018. Demographic, clinical and radiological data were collected. The Kaplan-Meier method was used to measure survival and predictors of survival were identified with the Cox regression model. RESULTS: A total of 98 patients were included (78.6% male), mean age was 58.5 (SD±/-9.9) and the median MELD was 13.3 (IQR 9.5-16). The indications were refractory ascites (RA), variceal bleeding (VB) and hepatic hydrothorax (HH). Median survival was 72 months (RA 46.4, VB 68.5 and HH 64.7) and transplant-free survival was 26 months. Clinical and technical success rates were 70.5% and 92.9% respectively. Age (HR 1.05), clinical success (HR 0.33), sodium (HR 0.92), renal failure (HR 2.46) and albumin (HR 0.35) were predictors of survival. Hepatic encephalopathy occurred in 28.6% of patients and TIPS dysfunction occurred in 16.3%. CONCLUSIONS: TIPS with 10-mm PTFE-covered stent is an effective and safe treatment for PH-related complications in patients with cirrhosis. Age, renal failure, sodium, albumin and clinical success are independent predictors of long-term survival.


Asunto(s)
Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Derivación Portosistémica Intrahepática Transyugular/métodos , Stents , Adulto , Anciano , Anciano de 80 o más Años , Ascitis/mortalidad , Ascitis/cirugía , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/mortalidad , Várices Esofágicas y Gástricas/cirugía , Femenino , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/mortalidad , Hemorragia Gastrointestinal/cirugía , Encefalopatía Hepática/epidemiología , Encefalopatía Hepática/mortalidad , Encefalopatía Hepática/prevención & control , Venas Hepáticas/diagnóstico por imagen , Venas Hepáticas/cirugía , Humanos , Hidrotórax/mortalidad , Hidrotórax/cirugía , Hipertensión Portal/mortalidad , Estimación de Kaplan-Meier , Cirrosis Hepática/mortalidad , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Derivación Portosistémica Intrahepática Transyugular/mortalidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/mortalidad , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Insuficiencia Renal/mortalidad , Estudios Retrospectivos , Albúmina Sérica , Sodio/sangre , Resultado del Tratamiento
18.
Int J Mol Sci ; 21(23)2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33260635

RESUMEN

Pyruvate is a central metabolite that connects many metabolic pathways in living organisms. To meet the cellular pyruvate requirements, the enterobacterium Escherichia coli has at least three pyruvate uptake systems-the H+/pyruvate symporter BtsT, and two thus far less well-characterized transporters, YhjX and CstA. BtsT and CstA belong to the putative carbon starvation (CstA) family (transporter classification TC# 2.A.114). We have created an E. coli mutant that cannot grow on pyruvate as the sole carbon source and used it to characterize CstA as a pyruvate transporter. Transport studies in intact cells confirmed that CstA is a highly specific pyruvate transporter with moderate affinity and is energized by a proton gradient. When cells of a reporter strain were cultured in complex medium, cstA expression was maximal only in stationary phase. A DNA affinity-capture assay combined with mass spectrometry and an in-vivo reporter assay identified Fis as a repressor of cstA expression, in addition to the known activator cAMP-CRP. The functional characterization and regulation of this second pyruvate uptake system provides valuable information for understanding the complexity of pyruvate sensing and uptake in E. coli.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Ácido Pirúvico/metabolismo , Transactivadores/metabolismo , Secuencia de Bases , Transporte Biológico , Quimiotaxis , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Mutación/genética , Fenotipo , Regiones Promotoras Genéticas/genética , Unión Proteica , Transactivadores/genética
19.
PLoS Pathog ; 12(2): e1005403, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26845335

RESUMEN

The inner membrane complex (IMC) of apicomplexan parasites is a specialised structure localised beneath the parasite's plasma membrane, and is important for parasite stability and intracellular replication. Furthermore, it serves as an anchor for the myosin A motor complex, termed the glideosome. While the role of this protein complex in parasite motility and host cell invasion has been well described, additional roles during the asexual life cycle are unknown. Here, we demonstrate that core elements of the glideosome, the gliding associated proteins GAP40 and GAP50 as well as members of the GAPM family, have critical roles in the biogenesis of the IMC during intracellular replication. Deletion or disruption of these genes resulted in the rapid collapse of developing parasites after initiation of the cell cycle and led to redistribution of other glideosome components.


Asunto(s)
Membrana Celular/metabolismo , Vesículas Citoplasmáticas/metabolismo , Proteínas de la Membrana/metabolismo , Biogénesis de Organelos , Proteínas Protozoarias/metabolismo , Toxoplasma/fisiología , Biomarcadores/metabolismo , Línea Celular , Membrana Celular/ultraestructura , Vesículas Citoplasmáticas/ultraestructura , Técnicas de Inactivación de Genes , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Proteínas de la Membrana/genética , Microscopía Electrónica de Transmisión , Microscopía por Video , Tamaño de los Orgánulos , Organismos Modificados Genéticamente , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte de Proteínas , Proteínas Protozoarias/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reproducción Asexuada , Toxoplasma/crecimiento & desarrollo , Toxoplasma/ultraestructura
20.
Adv Exp Med Biol ; 1059: 63-83, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29736569

RESUMEN

Osteoarthritis (OA) is the most prevalent joint disease characterized by pain and degenerative lesions of the cartilage, subchondral bone, and other joint tissues. The causes of OA remain incompletely understood. Over the years, it has become recognized that OA is a multifactorial disease. In particular, aging and trauma are the main risk factors identified for the development of OA; however, other factors such as genetic predisposition, obesity, inflammation, gender and hormones, or metabolic syndrome contribute to OA development and lead to a more severe outcome. While this disease mainly affects people older than 60 years, OA developed after joint trauma affects all range ages and has a particular impact on young individuals and people who have highest levels of physical activity such as athletes. Traumatic injury to the joint often results in joint instability or intra-articular fractures which lead to posttraumatic osteoarthritis (PTOA). In response to injury, several molecular mechanisms are activated, increasing the production and activation of different factors that contribute to the progression of OA.In this chapter, we have focused on the interactions and contribution of the multiple factors involved in joint destruction and progression of OA. In addition, we overview the main changes and molecular mechanisms related to OA pathogenesis.


Asunto(s)
Osteoartritis/etiología , Heridas y Lesiones/complicaciones , Envejecimiento/fisiología , Cartílago Articular/lesiones , Cartílago Articular/metabolismo , Cartílago Articular/fisiopatología , Causalidad , Condrocitos/patología , Progresión de la Enfermedad , Fracturas Óseas/complicaciones , Fracturas Óseas/fisiopatología , Predisposición Genética a la Enfermedad , Humanos , Inflamación/complicaciones , Inflamación/fisiopatología , Síndrome Metabólico/complicaciones , Síndrome Metabólico/fisiopatología , Modelos Biológicos , Obesidad/complicaciones , Obesidad/fisiopatología , Procedimientos Ortopédicos , Osteoartritis/genética , Osteoartritis/fisiopatología , Osteoartritis/terapia , Factores Sexuales , Ingeniería de Tejidos , Heridas y Lesiones/fisiopatología
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