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1.
Nature ; 583(7817): 560-566, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32699397

RESUMEN

There are concerns that recent climate change is altering the frequency and magnitude of river floods in an unprecedented way1. Historical studies have identified flood-rich periods in the past half millennium in various regions of Europe2. However, because of the low temporal resolution of existing datasets and the relatively low number of series, it has remained unclear whether Europe is currently in a flood-rich period from a long-term perspective. Here we analyse how recent decades compare with the flood history of Europe, using a new database composed of more than 100 high-resolution (sub-annual) historical flood series based on documentary evidence covering all major regions of Europe. We show that the past three decades were among the most flood-rich periods in Europe in the past 500 years, and that this period differs from other flood-rich periods in terms of its extent, air temperatures and flood seasonality. We identified nine flood-rich periods and associated regions. Among the periods richest in floods are 1560-1580 (western and central Europe), 1760-1800 (most of Europe), 1840-1870 (western and southern Europe) and 1990-2016 (western and central Europe). In most parts of Europe, previous flood-rich periods occurred during cooler-than-usual phases, but the current flood-rich period has been much warmer. Flood seasonality is also more pronounced in the recent period. For example, during previous flood and interflood periods, 41 per cent and 42 per cent of central European floods occurred in summer, respectively, compared with 55 per cent of floods in the recent period. The exceptional nature of the present-day flood-rich period calls for process-based tools for flood-risk assessment that capture the physical mechanisms involved, and management strategies that can incorporate the recent changes in risk.

2.
Nature ; 573(7772): 108-111, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31462777

RESUMEN

Climate change has led to concerns about increasing river floods resulting from the greater water-holding capacity of a warmer atmosphere1. These concerns are reinforced by evidence of increasing economic losses associated with flooding in many parts of the world, including Europe2. Any changes in river floods would have lasting implications for the design of flood protection measures and flood risk zoning. However, existing studies have been unable to identify a consistent continental-scale climatic-change signal in flood discharge observations in Europe3, because of the limited spatial coverage and number of hydrometric stations. Here we demonstrate clear regional patterns of both increases and decreases in observed river flood discharges in the past five decades in Europe, which are manifestations of a changing climate. Our results-arising from the most complete database of European flooding so far-suggest that: increasing autumn and winter rainfall has resulted in increasing floods in northwestern Europe; decreasing precipitation and increasing evaporation have led to decreasing floods in medium and large catchments in southern Europe; and decreasing snow cover and snowmelt, resulting from warmer temperatures, have led to decreasing floods in eastern Europe. Regional flood discharge trends in Europe range from an increase of about 11 per cent per decade to a decrease of 23 per cent. Notwithstanding the spatial and temporal heterogeneity of the observational record, the flood changes identified here are broadly consistent with climate model projections for the next century4,5, suggesting that climate-driven changes are already happening and supporting calls for the consideration of climate change in flood risk management.


Asunto(s)
Cambio Climático/estadística & datos numéricos , Inundaciones/estadística & datos numéricos , Ríos , Cambio Climático/historia , Europa (Continente) , Inundaciones/historia , Inundaciones/prevención & control , Mapeo Geográfico , Historia del Siglo XX , Historia del Siglo XXI , Lluvia , Estaciones del Año , Factores de Tiempo
3.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802280

RESUMEN

Monocyte to macrophage differentiation is characterized by the activation of various signal transduction pathways, which may be modulated by protein phosphorylation; however, the impact of protein kinases and phosphatases is not well understood yet. It has been demonstrated that actomyosin rearrangement during macrophage differentiation is dependent on Rho-associated protein kinase (ROCK). Myosin phosphatase (MP) target subunit-1 (MYPT1) is one of the major cellular substrates of ROCK, and MP is often a counter enzyme of ROCK; therefore, MP may also control macrophage differentiation. Changes in MP activity and the effects of MP activation were studied on PMA or l,25(OH)2D3-induced differentiation of monocytic THP-1 cells. During macrophage differentiation, phosphorylation of MYPT1 at Thr696 and Thr853 increased significantly, resulting in inhibition of MP. The ROCK inhibitor H1152 and the MP activator epigallocatechin-3-gallate (EGCG) attenuated MYPT1 phosphorylation and concomitantly decreased the extent of phosphorylation of 20 kDa myosin light chain. H1152 and EGCG pretreatment also suppressed the expression of CD11b and weakened the PMA-induced adherence of the cells. Our results indicate that MP activation/inhibition contributes to the efficacy of monocyte to macrophage differentiation, and this enzyme may be a target for pharmacological interventions in the control of disease states that are affected by excessive macrophage differentiation.


Asunto(s)
Diferenciación Celular/fisiología , Macrófagos/metabolismo , Monocitos/metabolismo , Fosfatasa de Miosina de Cadena Ligera/metabolismo , Células THP-1/metabolismo , Células Cultivadas , Humanos , Macrófagos/fisiología , Monocitos/fisiología , Fosforilación/fisiología , Transducción de Señal/fisiología , Células THP-1/fisiología , Quinasas Asociadas a rho/metabolismo
4.
Int J Mol Sci ; 21(12)2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32560122

RESUMEN

Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disorder characterized by the loss of motor control and cognitive ability, which eventually leads to death. The mutant huntingtin protein (HTT) exhibits an expansion of a polyglutamine repeat. The mechanism of pathogenesis is still not fully characterized; however, evidence suggests that post-translational modifications (PTMs) of HTT and upstream and downstream proteins of neuronal signaling pathways are involved. The determination and characterization of PTMs are essential to understand the mechanisms at work in HD, to define possible therapeutic targets better, and to challenge the scientific community to develop new approaches and methods. The discovery and characterization of a panoply of PTMs in HTT aggregation and cellular events in HD will bring us closer to understanding how the expression of mutant polyglutamine-containing HTT affects cellular homeostasis that leads to the perturbation of cell functions, neurotoxicity, and finally, cell death. Hence, here we review the current knowledge on recently identified PTMs of HD-related proteins and their pathophysiological relevance in the formation of abnormal protein aggregates, proteolytic dysfunction, and alterations of mitochondrial and metabolic pathways, neuroinflammatory regulation, excitotoxicity, and abnormal regulation of gene expression.


Asunto(s)
Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Enfermedad de Huntington/metabolismo , Humanos , Proteína Huntingtina/química , Enfermedad de Huntington/genética , Mutación , Pliegue de Proteína , Procesamiento Proteico-Postraduccional , Transducción de Señal
5.
J Enzyme Inhib Med Chem ; 34(1): 500-509, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30696301

RESUMEN

Several ellagitannins inhibited the activity of protein phosphatase-1 (PP1) and -2 A (PP2A) catalytic subunits (PP1c and PP2Ac) with preferential suppression of PP1c over PP2Ac. The inhibitory potency for PP1c followed the order of tellimagrandin I > mahtabin A > praecoxin B > 1.2-Di-O-galloyl-4.6-(S)-HHDP-ß-D-glucopyranose > pedunculagin with IC50 values ranging from 0.20 µM to 2.47 µM. The interaction of PP1c and tellimagrandin I was assessed by NMR saturation transfer difference, surface plasmon resonance, isothermal titration calorimetry, and microscale thermophoresis based binding techniques. Tellimagrandin I suppressed viability and phosphatase activity of HeLa cells, while mahtabin A was without effect. Conversely, mahtabin A increased the phosphorylation level of SNAP-25Thr138 and suppressed exocytosis of cortical synaptosomes, whereas tellimagrandin I was without influence. Our results establish ellagitannins as partially selective inhibitors of PP1 and indicate that these polyphenols may act distinctly in cellular systems depending on their membrane permeability and/or their actions on cell membranes.


Asunto(s)
Calorimetría/métodos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Proteína Fosfatasa 1/antagonistas & inhibidores , Proteína Fosfatasa 2/antagonistas & inhibidores , Animales , Supervivencia Celular/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Exocitosis/efectos de los fármacos , Células HeLa , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Ratones , Músculo Esquelético/enzimología , Fosforilación , Relación Estructura-Actividad , Resonancia por Plasmón de Superficie , Proteína 25 Asociada a Sinaptosomas/metabolismo , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
6.
Bioorg Med Chem ; 26(8): 1875-1884, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29501414

RESUMEN

Aralkyl and aryl selenoglycosides as well as glycosyl selenocarboxylate derivatives were assayed on the activity of protein phosphatase-1 (PP1) and -2A (PP2A) catalytic subunits (PP1c and PP2Ac) in search of compounds for PP1c and PP2Ac effectors. The majority of tested selenoglycosides activated both PP1c and PP2Ac by ∼2-4-fold in a phosphatase assay with phosphorylated myosin light chain substrate when the hydroxyl groups of the glycosyl moiety were acetylated, but they were without any effects in the non-acetylated forms. A peptide from the myosin phosphatase target subunit-1 (MYPT123-38) that included an RVxF PP1c-binding motif attenuated activation of PP1c by 2-Trifluoromethylbenzyl 2,3,4,6-tetra-O-acetyl-1-seleno-ß-d-glucopyranoside (TFM-BASG) and 4-Bromobenzyl 2,3,4,6-tetra-O-acetyl-1-seleno-ß-d-glucopyranoside (Br-BASG). MYPT123-38 stimulated PP2Ac and contributed to PP2Ac activation exerted by either Br-BASG or TFM-BASG. Br-BASG and TFM-BASG suppressed partially binding of PP1c to MYPT1 in surface plasmon resonance based binding experiments. Molecular docking predicted that the hydrophobic binding surfaces in PP1c for interaction with either the RVxF residues of PP1c-interactors or selenoglycosides are partially overlapped. Br-BASG and TFM-BASG caused a moderate increase in the phosphatase activity of HeLa cells in 1 h, and suppressed cell viability in 24 h incubations. In conclusion, our present study identified selenoglycosides as novel activators of PP1 and PP2A as well as provided insights into the structural background of their interactions establishing a molecular model for future design of more efficient phosphatase activator molecules.


Asunto(s)
Glicósidos/química , Proteína Fosfatasa 1/metabolismo , Proteína Fosfatasa 2/metabolismo , Selenio/química , Sitios de Unión , Dominio Catalítico , Supervivencia Celular/efectos de los fármacos , Glicósidos/metabolismo , Glicósidos/farmacología , Células HeLa , Humanos , Simulación del Acoplamiento Molecular , Péptidos/química , Péptidos/metabolismo , Unión Proteica , Resonancia por Plasmón de Superficie
7.
Biochim Biophys Acta ; 1852(1): 22-33, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25446992

RESUMEN

The number of ultraviolet (UV) radiation-induced skin diseases such as melanomas is on the rise. The altered behavior of keratinocytes is often coupled with signaling events in which Ser/Thr specific protein kinases and phosphatases regulate various cellular functions. In the present study the role of protein phosphatase-1 (PP1) was investigated in the response of human keratinocyte (HaCaT) cells and mouse skin to UV radiation. PP1 catalytic subunit (PP1c) isoforms, PP1cα/γ and PP1cδ, are all localized to the cytoskeleton and cytosol of keratinocytes, but PP1cδ was found to be dominant over PP1α/γ in the nucleus. PP1c-silencing in HaCaT cells decreased the phosphatase activity and suppressed the viability of the cells. Exposure to a 10 J/cm(2) UVA dose induced HaCaT cell death and resulted in a 30% decrease of phosphatase activity. PP1c-silencing and UVA irradiation altered the gene expression profile of HaCaT cells and suggested that the expression of 19 genes was regulated by the combined treatments with many of these genes being involved in malignant transformation. Microarray analysis detected altered expression levels of genes coding for melanoma-associated proteins such as keratin 1/10, calcium binding protein S100A8 and histone 1b. Treatment of Balb/c mice with the PP1-specific inhibitor tautomycin (TM) exhibited increased levels of keratin 1/10 and S100A8, and a decreased level of histone 1b proteins following UVA irradiation. Moreover, TM treatment increased pigmentation of the skin which was even more apparent when TM was followed by UVA irradiation. Our data identify PP1 as a regulator of the normal homeostasis of keratinocytes and the UV-response.


Asunto(s)
Homeostasis , Proteína Fosfatasa 1/metabolismo , Piel/diagnóstico por imagen , Rayos Ultravioleta , Animales , Dominio Catalítico , Línea Celular , Silenciador del Gen , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Proteína Fosfatasa 1/química , Proteína Fosfatasa 1/genética , Radiografía , Piel/enzimología , Piel/patología
8.
Water Resour Res ; 52(9): 6730-6750, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27840456

RESUMEN

This paper presents a novel framework that links imprecision (through a fuzzy approach) and stochastic uncertainty (through a Bayesian approach) in estimating flood probabilities from historical flood information and systematic flood discharge data. The method exploits the linguistic characteristics of historical source material to construct membership functions, which may be wider or narrower, depending on the vagueness of the statements. The membership functions are either included in the prior distribution or the likelihood function to obtain a fuzzy version of the flood frequency curve. The viability of the approach is demonstrated by three case studies that differ in terms of their hydromorphological conditions (from an Alpine river with bedrock profile to a flat lowland river with extensive flood plains) and historical source material (including narratives, town and county meeting protocols, flood marks and damage accounts). The case studies are presented in order of increasing fuzziness (the Rhine at Basel, Switzerland; the Werra at Meiningen, Germany; and the Tisza at Szeged, Hungary). Incorporating imprecise historical information is found to reduce the range between the 5% and 95% Bayesian credibility bounds of the 100 year floods by 45% and 61% for the Rhine and Werra case studies, respectively. The strengths and limitations of the framework are discussed relative to alternative (non-fuzzy) methods. The fuzzy Bayesian inference framework provides a flexible methodology that fits the imprecise nature of linguistic information on historical floods as available in historical written documentation.

9.
J Cell Mol Med ; 19(2): 396-407, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25283340

RESUMEN

In this paper, we investigated the isoform-specific roles of certain protein kinase C (PKC) isoforms in the regulation of skeletal muscle growth. Here, we provide the first intriguing functional evidence that nPKCδ (originally described as an inhibitor of proliferation in various cells types) is a key player in promoting both in vitro and in vivo skeletal muscle growth. Recombinant overexpression of a constitutively active nPKCδ in C2C12 myoblast increased proliferation and inhibited differentiation. Conversely, overexpression of kinase-negative mutant of nPKCδ (DN-nPKCδ) markedly inhibited cell growth. Moreover, overexpression of nPKCδ also stimulated in vivo tumour growth and induced malignant transformation in immunodeficient (SCID) mice whereas that of DN-nPKCδ suppressed tumour formation. The role of nPKCδ in the formation of rhabdomyosarcoma was also investigated where recombinant overexpression of nPKCδ in human rhabdomyosarcoma RD cells also increased cell proliferation and enhanced tumour formation in mouse xenografts. The other isoforms investigated (PKCα, ß, ε) exerted only minor (mostly growth-inhibitory) effects in skeletal muscle cells. Collectively, our data introduce nPKCδ as a novel growth-promoting molecule in skeletal muscles and invite further trials to exploit its therapeutic potential in the treatment of skeletal muscle malignancies.


Asunto(s)
Proliferación Celular/fisiología , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Músculo Esquelético/metabolismo , Proteína Quinasa C-delta/metabolismo , Animales , Línea Celular Tumoral , Células Cultivadas , Humanos , Ratones
10.
Transl Psychiatry ; 14(1): 18, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195548

RESUMEN

The partial N-methyl-D-aspartate receptor (NMDAR) agonist D-Cycloserine (DCS) has been evaluated for the treatment of a wide variety of psychiatric disorders, including dementia, schizophrenia, depression and for the augmentation of exposure-based psychotherapy. Most if not all of the potential psychiatric applications of DCS target an enhancement or restitution of cognitive functions, learning and memory. Their molecular correlate is long-term synaptic plasticity; and many forms of synaptic plasticity depend on the activation of NMDA receptors. Here, we comprehensively examined the modulation of different forms of synaptic plasticity in the hippocampus by DCS and its mechanism. We found that DCS positively modulates NMDAR-dependent forms of long-term synaptic plasticity (long-term synaptic potentiation, LTP, and long-term synaptic depression, LTD) in hippocampal brain slices of juvenile rats without affecting basal synaptic transmission. DCS binds to the D-serine/glycine binding site of the NMDAR. Pharmacological inhibition of this site prevented the induction of LTP, whereas agonism at the D-serine/glycine binding site augmented LTP and could functionally substitute for weak LTP induction paradigms. The most probable origin of endogenous D-serine are astrocytes, and its exocytosis is regulated by astrocytic metabotropic glutamate receptors (mGluR1). Functional eradication of astrocytes, inhibition of mGluR1 receptors and G-protein signaling in astrocytes adjacent to postsynaptic neurons prevented the induction of NMDAR-dependent forms of LTP and LTD. Our results support the enhancement of a bidirectional range of NMDAR-dependent hippocampal synaptic plasticity by DCS and D-serine-mediated gliotransmission. Therefore, the D-serine/glycine-binding site in NMDAR is a major target for psychopharmacological interventions targeting plasticity-related disorders.


Asunto(s)
Cicloserina , Receptores de N-Metil-D-Aspartato , Humanos , Animales , Ratas , Cicloserina/farmacología , Plasticidad Neuronal , Serina , Glicina , Hipocampo
11.
Acta Biol Hung ; 64(1): 71-85, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23567832

RESUMEN

This study compares the histological, cytological and biochemical effects of the cyanobacterial toxins microcystin-LR (MCY-LR) and cylindrospermopsin (CYN) in white mustard (Sinapis alba L.) seedlings, with special regard to the developing root system. Cyanotoxins induced different alterations, indicating their different specific biochemical activities. MCY-LR stimulated mitosis of root tip meristematic cells at lower concentrations (1 µg ml-1) and inhibited it at higher concentrations, while CYN had only inhibitory effects. Low CYN concentrations (0.01 µg ml-1) stimulated lateral root formation, whereas low MCY-LR concentrations increased only the number of lateral root primordia. Both inhibited lateral root development at higher concentrations. They induced lignifications, abnormal cell swelling and inhibited xylem differentiation in roots and shoots. MCY-LR and CYN induced the disruption of metaphase and anaphase spindles, causing altered cell divisions. Similar alterations could be related to decreased protein phosphatase (PP1 and PP2A) activities in shoots and roots. However, in vitro phosphatase assay with purified PP1 catalytic subunit proved that CYN in contrast to MCY-LR, decreased phosphatase activities of mustard in a non-specific way. This study intends to contribute to the understanding of the mechanisms of toxic effects of a protein phosphatase (MCY-LR) and a protein synthesis (CYN) inhibitory cyanotoxin in vascular plants.


Asunto(s)
Microcistinas/farmacología , Raíces de Plantas/efectos de los fármacos , Plantones/efectos de los fármacos , Sinapis/efectos de los fármacos , Uracilo/análogos & derivados , Alcaloides , Toxinas Bacterianas , Toxinas de Cianobacterias , Toxinas Marinas , Mitosis/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Plantones/crecimiento & desarrollo , Sinapis/crecimiento & desarrollo , Uracilo/farmacología
12.
Sci Data ; 10(1): 44, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658229

RESUMEN

There is a growing need for past weather and climate data to support science and decision-making. This paper describes the compilation and construction of a global multivariable (air temperature, pressure, precipitation sum, number of precipitation days) monthly instrumental climate database that encompasses a substantial body of the known early instrumental time series. The dataset contains series compiled from existing databases that start before 1890 (though continuing to the present) as well as a large amount of newly rescued data. All series underwent a quality control procedure and subdaily series were processed to monthly mean values. An inventory was compiled, and the collection was deduplicated based on coordinates and mutual correlations. The data are provided in a common format accompanied by the inventory. The collection totals 12452 meteorological records in 118 countries. The data can be used for climate reconstructions and analyses. It is the most comprehensive global monthly climate dataset for the preindustrial period so far.

13.
Sci Data ; 10(1): 402, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37353567

RESUMEN

Documentary climate data describe evidence of past climate arising from predominantly written historical documents such as diaries, chronicles, newspapers, or logbooks. Over the past decades, historians and climatologists have generated numerous document-based time series of local and regional climates. However, a global dataset of documentary climate time series has never been compiled, and documentary data are rarely used in large-scale climate reconstructions. Here, we present the first global multi-variable collection of documentary climate records. The dataset DOCU-CLIM comprises 621 time series (both published and hitherto unpublished) providing information on historical variations in temperature, precipitation, and wind regime. The series are evaluated by formulating proxy forward models (i.e., predicting the documentary observations from climate fields) in an overlapping period. Results show strong correlations, particularly for the temperature-sensitive series. Correlations are somewhat lower for precipitation-sensitive series. Overall, we ascribe considerable potential to documentary records as climate data, especially in regions and seasons not well represented by early instrumental data and palaeoclimate proxies.

14.
Genet Mol Biol ; 35(2): 424-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22888290

RESUMEN

A 10-year-old speechless, mentally deficient male, with low arylsulfatase A (ARSA) activity, and presumably, methachromatic leukodystrophy, underwent genetic evaluation. As the clinical picture was not compatible with this diagnosisan ARSA gene and chromosome analysis were performed, showing the presence of a pseudodeficiency ARSA allele and a de novo apparently balanced t(16;22)(p11.2;q13) translocation. A deletion on the long arm of chromosome 22 encompassing the ARSA gene, as shown by FISH and array-CGH, indicated a 22q13 deletion syndrome. This case illustrates the importance of detailed cytogenetic investigation in patients presenting low arylsulfatase A activity and atypical/unspecific clinical features.

15.
Int J Biometeorol ; 55(4): 595-611, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20953886

RESUMEN

In this paper, we present a 392-year-long preliminary temperature reconstruction for western Hungary. The reconstructed series is based on five vine- and grain-related historical phenological series from the town of Koszeg. We apply dendrochronological methods for both signal assessment of the phenological series and the resultant temperature reconstruction. As a proof of concept, the present reconstruction explains 57% of the temperature variance of May-July Budapest mean temperatures and is well verified with coefficient of efficiency values in excess of 0.45. The developed temperature reconstruction portrays warm conditions during the late seventeenth and early eighteenth centuries with a period of cooling until the coldest reconstructed period centred around 1815, which was followed by a period of warming until the 1860s. The phenological evidence analysed here represent an important data source from which non-biased estimates of past climate can be derived that may provide information at all possible time-scales.


Asunto(s)
Productos Agrícolas/historia , Grano Comestible/historia , Temperatura , Vitis/crecimiento & desarrollo , Agricultura/historia , Clima , Productos Agrícolas/crecimiento & desarrollo , Grano Comestible/crecimiento & desarrollo , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Hungría , Estaciones del Año
16.
Anticancer Agents Med Chem ; 21(9): 1092-1098, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32679023

RESUMEN

BACKGROUND: The Myosin Phosphatase (MP) holoenzyme is composed of a Protein Phosphatase type 1 (PP1) catalytic subunit and a regulatory subunit termed Myosin Phosphatase Target subunit 1 (MYPT1). Besides dephosphorylation of myosin, MP has been implicated in the control of cell proliferation via dephosphorylation and activation of the tumor suppressor gene products, retinoblastoma protein (pRb) and merlin. Inhibition of MP was shown to attenuate the drug-induced cell death of leukemic cells by chemotherapeutic agents, while activation of MP might have a sensitizing effect. OBJECTIVE: Recently, Epigallocatechin-Gallate (EGCG), a major component of green tea, was shown to activate MP by inducing the dephosphorylation of MYPT1 at phospho-Thr696 (MYPT1pT696), which might confer enhanced chemosensitivity to cancer cells. METHODS: THP-1 leukemic cells were treated with EGCG and Daunorubicin (DNR) and cell viability was analyzed. Phosphorylation of tumor suppressor proteins was detected by Western blotting. RESULTS: EGCG or DNR (at sub-lethal doses) alone had moderate effects on cell viability, while the combined treatment caused a significant decrease in the number of viable cells by enhancing apoptosis and decreasing proliferation. EGCG plus DNR decreased the phosphorylation level of MYPT1pT696, which was accompanied by prominent dephosphorylation of pRb. In addition, significant dephosphorylation of merlin was observed when EGCG and DNR were applied together. CONCLUSION: Our results suggest that EGCG-induced activation of MP might have a regulatory function in mediating the chemosensitivity of leukemic cells via dephosphorylation of tumor suppressor proteins.


Asunto(s)
Antineoplásicos/farmacología , Catequina/análogos & derivados , Daunorrubicina/farmacología , Fosfatasa de Miosina de Cadena Ligera/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Catequina/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Daunorrubicina/síntesis química , Daunorrubicina/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Fosfatasa de Miosina de Cadena Ligera/metabolismo , Relación Estructura-Actividad , Células THP-1 , Células Tumorales Cultivadas
17.
J Virol Methods ; 293: 114165, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33872650

RESUMEN

Seeing the global emergence and the lack of a definitive cure for COVID-19, it is essential to find the most sensitive and specific detection method to identify infected patients in a timely manner. Our paper aims to compare the clinical sensitivity of different commercial RT-qPCR (Genesig, 1copy, DNA-Techonolgy and Charité primer-probe sets), isothermal PCR (Ustar Isothermal Amplification-Real Time Fluorescent Assay) and immunochromatographic antigen detection (BIOCREDIT COVID-19 Ag) assays developed to use in laboratory diagnosis of COVID-19. A total of 119 nasopharyngeal swab specimens were collected from symptomatic patients. A subset of samples, positive with two RT-qPCR assays were then tested with isothermal PCR and rapid antigen tests. Of the 119 specimens, 65 were positive by at least two PCR assays. All PCR assays showed substantial or perfect match, although some variations in the clinical performance was observed. Of the 37 and 32 remnant nasopharyngeal samples positive by RT-qPCR, respectively, three were positive by the BIOCREDIT COVID-19 Ag and 14 were detected by the isothermal amplification assay. In conclusion, in the clinical settings we recorded that each of the RT-qPCR assays was superior to other test formats, in particular, the routine use of the DNA-technology assay is recommended. Although alternative recommendations exist, we belive that the use of isothermal amplifiaction assays and antigen rapid tests for COVID-19 diagnosis can only serve as adjuncts while awaiting the PCR result because of their high false-negative rate.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Pruebas en el Punto de Atención , SARS-CoV-2/genética , Antígenos Virales/análisis , Humanos , Juego de Reactivos para Diagnóstico , Flujo de Trabajo
18.
Platelets ; 21(7): 555-62, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20670106

RESUMEN

Platelet activation is accompanied with the phosphorylation of a number of proteins on serine (Ser) and threonine (Thr) residues. The phosphorylation level of these proteins is dependent upon the protein kinase/phosphatase activity ratio. The aim of this study was to investigate the consequences of inhibiting protein phosphatase 1 (PP1) and 2A (PP2A) on platelet functions. Protein phosphatases were inhibited by preincubation of platelet rich plasma (PRP) samples with calyculin-A (CLA). Subsequently, platelets were activated by thrombin-receptor activating peptide (TRAP) and platelet aggregation, platelet-derived microparticle (PMP) formation, surface expressions of P-selectin (CD62), lysosome-associated membrane protein (CD63), glycoprotein Ib and IIb were examined. Phosphatase activity was determined by using phosphorylated 20 kDa myosin light chain (P-MLC20) as substrate. In CLA-treated platelets substantial decrease of P-MLC20 phosphatase activity was observed. CLA significantly suppressed TRAP-induced surface expression of P-selectin and CD63 in a concentration-dependent manner as compared to non-treated samples and moderately decreased platelet aggregation. In TRAP-activated samples, 50 nM of CLA pretreatment completely abolished the level of PMPs and the prevention of GPIb downregulation was also observed; however, no difference was found in GPIIb expression. In conclusion, PP1 and PP2A-catalyzed dephosphorylation processes have crucial roles in PMP formation and in the regulation of alpha-granule and lysosome secretion in human platelets.


Asunto(s)
Plaquetas/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Oxazoles/farmacología , Activación Plaquetaria/efectos de los fármacos , Proteína Fosfatasa 1/antagonistas & inhibidores , Proteína Fosfatasa 2/antagonistas & inhibidores , Plaquetas/enzimología , Plaquetas/metabolismo , Plaquetas/fisiología , Regulación hacia Abajo , Humanos , Toxinas Marinas , Selectina-P/antagonistas & inhibidores , Selectina-P/biosíntesis , Selectina-P/sangre , Fragmentos de Péptidos/farmacología , Activación Plaquetaria/fisiología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteína Fosfatasa 1/sangre , Proteína Fosfatasa 2/sangre , Receptores de IgG/antagonistas & inhibidores , Receptores de IgG/biosíntesis , Receptores de IgG/sangre
19.
Sci Rep ; 10(1): 22412, 2020 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-33376244

RESUMEN

Northern peatlands typically develop through succession from fens dominated by the moss family Amblystegiaceae to bogs dominated by the moss genus Sphagnum. How the different plants and abiotic environmental conditions provided in Amblystegiaceae and Sphagnum peat shape the respective moss associated microbial communities is unknown. Through a large-scale molecular and biogeochemical study spanning Arctic, sub-Arctic and temperate regions we assessed how the endo- and epiphytic microbial communities of natural northern peatland mosses relate to peatland type (Sphagnum and Amblystegiaceae), location, moss taxa and abiotic environmental variables. Microbial diversity and community structure were distinctly different between Amblystegiaceae and Sphagnum peatlands, and within each of these two peatland types moss taxon explained the largest part of microbial community variation. Sphagnum and Amblystegiaceae shared few (< 1% of all operational taxonomic units (OTUs)) but strikingly abundant (up to 65% of relative abundance) OTUs. This core community overlapped by one third with the Sphagnum-specific core-community. Thus, the most abundant microorganisms in Sphagnum that are also found in all the Sphagnum plants studied, are the same OTUs as those few shared with Amblystegiaceae. Finally, we could confirm that these highly abundant OTUs were endophytes in Sphagnum, but epiphytes on Amblystegiaceae. We conclude that moss taxa and abiotic environmental variables associate with particular microbial communities. While moss taxon was the most influential parameter, hydrology, pH and temperature also had significant effects on the microbial communities. A small though highly abundant core community is shared between Sphagnum and Amblystegiaceae.


Asunto(s)
Biodiversidad , Bryopsida/microbiología , Microbiota/fisiología , Sphagnopsida/microbiología , Humedales , Regiones Árticas
20.
Am J Med Genet A ; 149A(6): 1302-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19449429

RESUMEN

We report on a 4-year-old girl who presented with microcephaly, multiple minor anomalies of face and limbs, congenital heart defect, hypotonia, neuropsychomotor delay, deafness and seizures. A GTG-banded karyotype identified an additional fragment of unknown origin on the terminal region of 4p. Parental karyotypes were normal. FISH analysis using a whole chromosome paint probe for chromosome 4 and subtelomere probes showed a signal on the entire add (4) chromosome and loss of the 4p subtelomere region, respectively. Additional analysis using microsatellite markers for chromosome 4 and whole-genome array comparative genomic hybridization (array-CGH) identified a duplication of the region 4p13 --> 4p16.3. Her karyotype was thus interpreted as an inverted duplication with terminal deletion of 4p: 46,XX,der(4)(:p13 --> p16.3::p16.3 --> qter). The clinical features of our patient differed from those typically observed in Wolf-Hirschhorn syndrome and were more compatible with duplication 4(p14 --> p16.3), with preservation of the WHS critical region.


Asunto(s)
Inversión Cromosómica , Cromosomas Humanos Par 4 , Eliminación de Gen , Duplicación de Gen , Síndrome de Wolf-Hirschhorn , Anomalías Múltiples/genética , Preescolar , Pintura Cromosómica/métodos , Hibridación Genómica Comparativa/métodos , ADN/genética , Femenino , Marcadores Genéticos , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Repeticiones de Microsatélite , Mapeo Físico de Cromosoma , Síndrome
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