RESUMEN
Proteins of the bromodomain and extra-terminal (BET) domain family are epigenetic readers that bind acetylated histones through their bromodomains to regulate gene transcription. Dual-bromodomain BET inhibitors (DbBi) that bind with similar affinities to the first (BD1) and second (BD2) bromodomains of BRD2, BRD3, BRD4 and BRDt have displayed modest clinical activity in monotherapy cancer trials. A reduced number of thrombocytes in the blood (thrombocytopenia) as well as symptoms of gastrointestinal toxicity are dose-limiting adverse events for some types of DbBi1-5. Given that similar haematological and gastrointestinal defects were observed after genetic silencing of Brd4 in mice6, the platelet and gastrointestinal toxicities may represent on-target activities associated with BET inhibition. The two individual bromodomains in BET family proteins may have distinct functions7-9 and different cellular phenotypes after pharmacological inhibition of one or both bromodomains have been reported10,11, suggesting that selectively targeting one of the bromodomains may result in a different efficacy and tolerability profile compared with DbBi. Available compounds that are selective to individual domains lack sufficient potency and the pharmacokinetics properties that are required for in vivo efficacy and tolerability assessment10-13. Here we carried out a medicinal chemistry campaign that led to the discovery of ABBV-744, a highly potent and selective inhibitor of the BD2 domain of BET family proteins with drug-like properties. In contrast to the broad range of cell growth inhibition induced by DbBi, the antiproliferative activity of ABBV-744 was largely, but not exclusively, restricted to cell lines of acute myeloid leukaemia and prostate cancer that expressed the full-length androgen receptor (AR). ABBV-744 retained robust activity in prostate cancer xenografts, and showed fewer platelet and gastrointestinal toxicities than the DbBi ABBV-07514. Analyses of RNA expression and chromatin immunoprecipitation followed by sequencing revealed that ABBV-744 displaced BRD4 from AR-containing super-enhancers and inhibited AR-dependent transcription, with less impact on global transcription compared with ABBV-075. These results underscore the potential value of selectively targeting the BD2 domain of BET family proteins for cancer therapy.
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Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/química , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Dominios Proteicos/efectos de los fármacos , Piridinas/farmacología , Pirroles/farmacología , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/química , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Elementos de Facilitación Genéticos/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Piridinas/efectos adversos , Piridinas/toxicidad , Pirroles/efectos adversos , Pirroles/toxicidad , Ratas , Receptores Androgénicos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The selenium-binding protein 1 (SELENBP1) has been reported to be up-regulated in the prefrontal cortex (PFC) of schizophrenia patients in postmortem reports. However, no causative link between SELENBP1 and schizophrenia has yet been established. Here, we provide evidence linking the upregulation of SELENBP1 in the PFC of mice with the negative symptoms of schizophrenia. We verified the levels of SELENBP1 transcripts in postmortem PFC brain tissues from patients with schizophrenia and matched healthy controls. We also generated transgenic mice expressing human SELENBP1 (hSELENBP1 Tg) and examined their neuropathological features, intrinsic firing properties of PFC 2/3-layer pyramidal neurons, and frontal cortex (FC) electroencephalographic (EEG) responses to auditory stimuli. Schizophrenia-like behaviors in hSELENBP1 Tg mice and mice expressing Selenbp1 in the FC were assessed. SELENBP1 transcript levels were higher in the brains of patients with schizophrenia than in those of matched healthy controls. The hSELENBP1 Tg mice displayed negative endophenotype behaviors, including heterotopias- and ectopias-like anatomical deformities in upper-layer cortical neurons and social withdrawal, deficits in nesting, and anhedonia-like behavior. Additionally, hSELENBP1 Tg mice exhibited reduced excitabilities of PFC 2/3-layer pyramidal neurons and abnormalities in EEG biomarkers observed in schizophrenia. Furthermore, mice overexpressing Selenbp1 in FC showed deficits in sociability. These results suggest that upregulation of SELENBP1 in the PFC causes asociality, a negative symptom of schizophrenia.
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Esquizofrenia , Humanos , Animales , Ratones , Esquizofrenia/genética , Esquizofrenia/metabolismo , Corteza Prefrontal/metabolismo , Células Piramidales/metabolismo , Encéfalo/metabolismo , Ratones Transgénicos , Proteínas de Unión al Selenio/genética , Proteínas de Unión al Selenio/metabolismoRESUMEN
Importance: The Cluster Randomized Trial of PSA Testing for Prostate Cancer (CAP) reported no effect of prostate-specific antigen (PSA) screening on prostate cancer mortality at a median 10-year follow-up (primary outcome), but the long-term effects of PSA screening on prostate cancer mortality remain unclear. Objective: To evaluate the effect of a single invitation for PSA screening on prostate cancer-specific mortality at a median 15-year follow-up compared with no invitation for screening. Design, Setting, and Participants: This secondary analysis of the CAP randomized clinical trial included men aged 50 to 69 years identified at 573 primary care practices in England and Wales. Primary care practices were randomized between September 25, 2001, and August 24, 2007, and men were enrolled between January 8, 2002, and January 20, 2009. Follow-up was completed on March 31, 2021. Intervention: Men received a single invitation for a PSA screening test with subsequent diagnostic tests if the PSA level was 3.0 ng/mL or higher. The control group received standard practice (no invitation). Main Outcomes and Measures: The primary outcome was reported previously. Of 8 prespecified secondary outcomes, results of 4 were reported previously. The 4 remaining prespecified secondary outcomes at 15-year follow-up were prostate cancer-specific mortality, all-cause mortality, and prostate cancer stage and Gleason grade at diagnosis. Results: Of 415â¯357 eligible men (mean [SD] age, 59.0 [5.6] years), 98% were included in these analyses. Overall, 12â¯013 and 12â¯958 men with a prostate cancer diagnosis were in the intervention and control groups, respectively (15-year cumulative risk, 7.08% [95% CI, 6.95%-7.21%] and 6.94% [95% CI, 6.82%-7.06%], respectively). At a median 15-year follow-up, 1199 men in the intervention group (0.69% [95% CI, 0.65%-0.73%]) and 1451 men in the control group (0.78% [95% CI, 0.73%-0.82%]) died of prostate cancer (rate ratio [RR], 0.92 [95% CI, 0.85-0.99]; P = .03). Compared with the control, the PSA screening intervention increased detection of low-grade (Gleason score [GS] ≤6: 2.2% vs 1.6%; P < .001) and localized (T1/T2: 3.6% vs 3.1%; P < .001) disease but not intermediate (GS of 7), high-grade (GS ≥8), locally advanced (T3), or distally advanced (T4/N1/M1) tumors. There were 45â¯084 all-cause deaths in the intervention group (23.2% [95% CI, 23.0%-23.4%]) and 50â¯336 deaths in the control group (23.3% [95% CI, 23.1%-23.5%]) (RR, 0.97 [95% CI, 0.94-1.01]; P = .11). Eight of the prostate cancer deaths in the intervention group (0.7%) and 7 deaths in the control group (0.5%) were related to a diagnostic biopsy or prostate cancer treatment. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, a single invitation for PSA screening compared with standard practice without routine screening reduced prostate cancer deaths at a median follow-up of 15 years. However, the absolute reduction in deaths was small. Trial Registration: isrctn.org Identifier: ISRCTN92187251.
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Detección Precoz del Cáncer , Antígeno Prostático Específico , Neoplasias de la Próstata , Anciano , Humanos , Masculino , Persona de Mediana Edad , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Inglaterra/epidemiología , Estudios de Seguimiento , Tamizaje Masivo/métodos , Tamizaje Masivo/estadística & datos numéricos , Clasificación del Tumor , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/terapia , Gales/epidemiología , Ultrasonografía , Biopsia Guiada por ImagenRESUMEN
OBJECTIVE: Glycogen storage diseases (GSDs) are severe human disorders resulting from abnormal glucose metabolism, and all previously described GSDs segregate as autosomal recessive or X-linked traits. In this study, we aimed to molecularly characterize the first family with a dominant GSD. METHODS: We describe a dominant GSD family with 13 affected members presenting with adult-onset muscle weakness, and we provide clinical, metabolic, histological, and ultrastructural data. We performed exome sequencing to uncover the causative gene, and functional experiments in the cell model and on recombinant proteins to investigate the pathogenic effect of the identified mutation. RESULTS: We identified a heterozygous missense mutation in PYGM segregating with the disease in the family. PYGM codes for myophosphorylase, the enzyme catalyzing the initial step of glycogen breakdown. Enzymatic tests revealed that the PYGM mutation impairs the AMP-independent myophosphorylase activity, whereas the AMP-dependent activity was preserved. Further functional investigations demonstrated an altered conformation and aggregation of mutant myophosphorylase, and the concurrent accumulation of the intermediate filament desmin in the myofibers of the patients. INTERPRETATION: Overall, this study describes the first example of a dominant glycogen storage disease in humans, and elucidates the underlying pathomechanisms by deciphering the sequence of events from the PYGM mutation to the accumulation of glycogen in the muscle fibers. ANN NEUROL 2020;88:274-282.
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Glucógeno Fosforilasa de Forma Muscular/genética , Enfermedad del Almacenamiento de Glucógeno/diagnóstico , Enfermedad del Almacenamiento de Glucógeno/genética , Mutación/genética , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , LinajeRESUMEN
Extended spectrum ß-lactamase (ESBL)-producing Escherichia coli have been found in healthy individuals in Indonesia and Vietnam. The ISEcp1-blaCTX-M transposition unit of ESBL-producing bacterial isolates has been considered responsible for the production of CTX-M type ESBL and it is important for the dissemination of blaCTX-M . This study aimed to characterize the upstream genetic structure (UGS) of E. coli isolates possessing blaCTX-M-1 group and/or blaCTX-M-9 group genes obtained from healthy individuals in Indonesia and Vietnam. A total of 501 CTX-M type ESBL-producing E. coli isolates possessing blaCTX-M-1 group and/or blaCTX-M-9 group genes were obtained from healthy individuals of the two countries in 2018. The UGSs of the ISEcp1-blaCTX-M transposition unit of the 501 ESBL-producing E. coli isolates were amplified by barcode-adaptor-ligation-mediated PCR and analyzed using the Nanopore sequencer. The obtained sequence information was used to classify the UGSs of the ISEcp1-blaCTX-M transposition unit. From the 501 ESBL-producing E. coli isolates, 502 UGSs were obtained, which were classified into 85 UGS types based on the sequence. ISEcp1 of 359 (71.5%) of the 502 UGSs was disrupted by gene insertion, and ISEcp1-blaCTX-M transposition unit of most (87.1%) of the determined UGSs was confirmed as plasmidic. Only 6 (7.1%) of the 85 UGS types were common to both countries. Our results indicated that many different UGSs of ISEcp1-blaCTX-M transposition units were detected in Indonesia and Vietnam; hence, we suggest that structurally different kinds of plasmids harboring blaCTX-M were separately distributed in the two countries.
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Infecciones por Escherichia coli , Escherichia coli , beta-Lactamasas , Antibacterianos , Pueblo Asiatico , Escherichia coli/genética , Humanos , Indonesia , Plásmidos , Vietnam , beta-Lactamasas/genéticaRESUMEN
As more countries commit to a net-zero GHG emission target, we need a whole energy and industrial system approach to decarbonization rather than focus on individual emitters. This paper presents a techno-economic analysis of monoethanolamine-based post-combustion capture to explore opportunities over a diverse range of power and industrial applications. The following ranges were investigated: feed gas flow rate between 1-1000 kg ·s-1, gas CO2 concentrations of 2-42%mol, capture rates of 70-99%, and interest rates of 2-20%. The economies of scale are evident when the flue gas flow rate is <20 kg ·s-1 and gas concentration is below 20%mol CO2. In most cases, increasing the capture rate from 90 to 95% has a negligible impact on capture cost, thereby reducing CO2 emissions at virtually no additional cost. The majority of the investigated space has an operating cost fraction above 50%. In these instances, reducing the cost of capital (i.e., interest rate) has a minor impact on the capture cost. Instead, it would be more beneficial to reduce steam requirements. We also provide a surrogate model which can evaluate capture cost from inputs of the gas flow rate, CO2 composition, capture rate, interest rate, steam cost, and electricity cost.
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Aminas , Dióxido de Carbono , Electricidad , Etanolamina , VaporRESUMEN
INTRODUCTION: Because blaCTX-M is responsible for resistance of bacteria to the third generation cephalosporins, location of blaCTX-M could be a good indicator for classifying bacterial isolates harboring blaCTX-M in molecular epidemiology. However, determination of blaCTX-M location has been difficult when multiple copies of ISEcp1 were found on bacterial genome. We aimed to establish a high-throughput analytical method for upstream genetic structures (UGS) of ISEcp1 to facilitate determination of blaCTX-M location. METHODS: Extracted DNA samples obtained from 168 Escherichia coli isolates possessing blaCTX-M were digested by restriction enzyme, HaeIII, and the digested DNA fragments were ligated with homemade barcode adaptors. Then, DNA fragments containing UGS of ISEcp1 were amplified and subjected to the Nanopore sequencer. RESULTS: Nucleotide sequences and locations of 168 UGSs obtained from the examined E. coli isolates were determined. Among the 168 determined UGSs, 150 (89.3%) UGS were confirmed on plasmid and classified into eight types. Interestingly, coding sequence of ISEcp1 transposase gene in seven of the eight types were disrupted by IS26 insertion. The remaining 18 (10.7%) UGSs were observed in identical chromosomal region. The obtained nucleotide sequences the locations of UGSs were confirmed by conventional capillary sequencer and Southern blotting, respectively, and any discrepant result was not observed with these confirmation procedures. CONCLUSIONS: Our results indicated that the established method was efficient for simultaneously determining at least 100 different UGS, and suggested that the determined UGSs of ISEcp1-blaCTX-M transposition unit was useful for classification of bacterial isolates harboring blaCTX-M.
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Infecciones por Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Escherichia coli/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Plásmidos/genética , beta-Lactamasas/genéticaRESUMEN
This study investigated the contamination levels and sources of As and Cd vicinity area from Nui Phao mine that is one of the largest tungsten (W) open pit mines in the world. Soil and plant samples were collected from the study area to identify the concentrations of As and Cd using aqua-regia or HNO3 digestion. According to the Vietnamese agricultural soil criteria, all soil samples were contaminated with As and Cd. The distribution of As concentration is related to the distance from the Nui Phao mine. The higher As concentrations were measured in the area close to the mine. However, the Cd distribution in the soil showed a different pattern from As. Enrichment factor and Geoaccumulation Index (Igeo) indicated that As in the soil is derived from the mining activities, while Cd could have other geogenic or anthropogenic sources. The ranges of As and Cd concentration in polished rice grains in the Nui Phao mine area exceeded the CODEX criteria (0.2 mg/kg), which indicated extreme contamination. The arsenic concentration between soil and plant samples was determined to be a positive correlation, while the Cd concentration showed a negative correlation, implying that As and Cd have different geochemical behavior based on their sources.
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Arsénico/análisis , Cadmio/análisis , Minería , Contaminantes del Suelo/análisis , Agricultura/normas , Grano Comestible/química , Monitoreo del Ambiente , Oryza/química , Suelo/química , Suelo/normas , VietnamRESUMEN
Amyotrophic lateral sclerosis (ALS) patients show progressive respiratory muscle weakness leading to death from respiratory failure. However, there are no data on diaphragm histological changes in ALS patients and how they correlate with routine respiratory measurements.We collected 39 diaphragm biopsies concomitantly with laparoscopic insertion of intradiaphragmatic electrodes during a randomised controlled trial evaluating early diaphragm pacing in ALS (https://clinicaltrials.gov; NCT01583088). Myofibre type, size and distribution were evaluated by immunofluorescence microscopy and correlated with spirometry, respiratory muscle strength and phrenic nerve conduction parameters. The relationship between these variables and diaphragm atrophy was assessed using multivariate regression models.All patients exhibited significant slow- and fast-twitch diaphragmatic atrophy. Vital capacity (VC), maximal inspiratory pressure, sniff nasal inspiratory pressure (SNIP) and twitch transdiaphragmatic pressure did not correlate with the severity of diaphragm atrophy. Inspiratory capacity (IC) correlated modestly with slow-twitch myofibre atrophy. Supine fall in VC correlated weakly with fast-twitch myofibre atrophy. Multivariate analysis showed that IC, SNIP and functional residual capacity were independent predictors of slow-twitch diaphragmatic atrophy, but not fast-twitch atrophy.Routine respiratory tests are poor predictors of diaphragm structural changes. Improved detection of diaphragm atrophy is essential for clinical practice and for management of trials specifically targeting diaphragm muscle function.
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Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/fisiopatología , Atrofia/diagnóstico , Atrofia/fisiopatología , Diafragma/fisiopatología , Respiración , Tejido Adiposo/patología , Biopsia , Electrodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Debilidad Muscular/fisiopatología , Análisis de Regresión , Pruebas de Función Respiratoria , Insuficiencia Respiratoria/fisiopatología , Músculos Respiratorios/fisiopatología , Ultrasonografía , Capacidad VitalRESUMEN
The phototrophic cyanobacterium Halomicronema hongdechloris shows far-red light-induced accumulation of chlorophyll (Chl) f, but the involvement of the pigment in photosynthetic energy harvesting by photosystem (PS) II is controversially discussed. While H. hongdechloris contains negligible amounts of Chl f in white-light culture conditions, the ratio of Chl f to Chl a is reversibly changed up to 1:8 under illumination with far-red light (720-730 nm). We performed UV-Vis absorption spectroscopy, time-integrated and time-resolved fluorescence spectroscopy for the calculation of decay-associated spectra (DAS) to determine excitation energy transfer (EET) processes between photosynthetic pigments in intact H. hongdechloris filaments. In cells grown under white light, highly efficient EET occurs from phycobilisomes (PBSs) to Chl a with an apparent time constant of about 100 ps. Charge separation occurs with a typical apparent time constant of 200-300 ps from Chl a. After 3-4 days of growth under far-red light, robust Chl f content was observed in H. hongdechloris and EET from PBSs reached Chl f efficiently within 200 ps. It is proposed based on mathematical modeling by rate equation systems for EET between the PBSs and PSII and subsequent electron transfer (ET) that charge separation occurs from Chl a and excitation energy is funneled from Chl f to Chl a via an energetically uphill EET driven by entropy, which is effective because the number of Chl a molecules coupled to Chl f is at least eight- to tenfold larger than the corresponding number of Chl f molecules. The long lifetime of Chl f molecules in contact to a tenfold larger pool of Chl a molecules allows Chl f to act as an intermediate energy storage level, from which the Gibbs free energy difference between Chl f and Chl a can be overcome by taking advantage from the favorable ratio of degeneracy coefficients, which formally represents a significant entropy gain in the Eyring formulation of the Arrhenius law. Direct evidence for energetically uphill EET and charge separation in PSII upon excitation of Chl f via anti-Stokes fluorescence in far-red light-adapted H. hongdechloris cells was obtained: Excitation by 720 nm laser light resulted in robust Chl a fluorescence at 680 nm that was distinctly temperature-dependent and, notably, increased upon DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) treatment in far-red light-adapted cells. Thus, rather than serving as an excitation energy trap, Chl f in far-red light-adapted H. hongdechloris cells is directly contributing to oxygenic photosynthesis at PSII.
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Clorofila/análogos & derivados , Luz , Fotosíntesis/fisiología , Clorofila/metabolismo , Entropía , Fotosíntesis/genética , Complejo de Proteína del Fotosistema II/metabolismoRESUMEN
BACKGROUND: Accumulating evidence suggests that genome plasticity allows filamentous plant pathogens to adapt to changing environments. Recently, the generalist plant pathogen Phytophthora ramorum has been documented to undergo irreversible phenotypic alterations accompanied by chromosomal aberrations when infecting trunks of mature oak trees (genus Quercus). In contrast, genomes and phenotypes of the pathogen derived from the foliage of California bay (Umbellularia californica) are usually stable. We define this phenomenon as host-induced phenotypic diversification (HIPD). P. ramorum also causes a severe foliar blight in some ornamental plants such as Rhododendron spp. and Viburnum spp., and isolates from these hosts occasionally show phenotypes resembling those from oak trunks that carry chromosomal aberrations. The aim of this study was to investigate variations in phenotypes and genomes of P. ramorum isolates from non-oak hosts and substrates to determine whether HIPD changes may be equivalent to those among isolates from oaks. RESULTS: We analyzed genomes of diverse non-oak isolates including those taken from foliage of Rhododendron and other ornamental plants, as well as from natural host species, soil, and water. Isolates recovered from artificially inoculated oak logs were also examined. We identified diverse chromosomal aberrations including copy neutral loss of heterozygosity (cnLOH) and aneuploidy in isolates from non-oak hosts. Most identified aberrations in non-oak hosts were also common among oak isolates; however, trisomy, a frequent type of chromosomal aberration in oak isolates was not observed in isolates from Rhododendron. CONCLUSION: This work cross-examined phenotypic variation and chromosomal aberrations in P. ramorum isolates from oak and non-oak hosts and substrates. The results suggest that HIPD comparable to that occurring in oak hosts occurs in non-oak environments such as in Rhododendron leaves. Rhododendron leaves are more easily available than mature oak stems and thus can potentially serve as a model host for the investigation of HIPD, the newly described plant-pathogen interaction.
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Aberraciones Cromosómicas , Genómica , Interacciones Huésped-Parásitos , Fenotipo , Phytophthora/genética , Variaciones en el Número de Copia de ADN , Haplotipos , Phytophthora/fisiología , Umbellularia/parasitologíaRESUMEN
Novel conformationally constrained BET bromodomain inhibitors have been developed. These inhibitors were optimized in two similar, yet distinct chemical series, the 6-methyl-1H-pyrrolo[2,3-c]pyridin-7(6H)-ones (A) and the 1-methyl-1H-pyrrolo[2,3-c]pyridin-7(6H)-ones (B). Each series demonstrated excellent activity in binding and cellular assays, and lead compounds from each series demonstrated significant efficacy in in vivo tumor xenograft models.
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Proteínas Nucleares/antagonistas & inhibidores , Piridonas/química , Factores de Transcripción/antagonistas & inhibidores , Animales , Sitios de Unión , Proteínas de Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Semivida , Humanos , Ratones , Microsomas/metabolismo , Simulación de Dinámica Molecular , Mieloma Múltiple/tratamiento farmacológico , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Piridonas/farmacocinética , Piridonas/farmacología , Piridonas/uso terapéutico , Relación Estructura-Actividad , Factores de Transcripción/metabolismo , Trasplante HeterólogoRESUMEN
Cancer cells have an unusually high requirement for the central and intermediary metabolite nicotinamide adenine dinucleotide (NAD+), and NAD+ depletion ultimately results in cell death. The rate limiting step within the NAD+ salvage pathway required for converting nicotinamide to NAD+ is catalyzed by nicotinamide phosphoribosyltransferase (NAMPT). Targeting NAMPT has been investigated as an anti-cancer strategy, and several highly selective small molecule inhibitors have been found to potently inhibit NAMPT in cancer cells, resulting in NAD+ depletion and cytotoxicity. To identify mechanisms that could cause resistance to NAMPT inhibitor treatment, we generated a human fibrosarcoma cell line refractory to the highly potent and selective NAMPT small molecule inhibitor, GMX1778. We uncovered novel and unexpected mechanisms of resistance including significantly increased expression of quinolinate phosphoribosyl transferase (QPRT), a key enzyme in the de novo NAD+ synthesis pathway. Additionally, exome sequencing of the NAMPT gene in the resistant cells identified a single heterozygous point mutation that was not present in the parental cell line. The combination of upregulation of the NAD+ de novo synthesis pathway through QPRT over-expression and NAMPT mutation confers resistance to GMX1778, but the cells are only partially resistant to next-generation NAMPT inhibitors. The resistance mechanisms uncovered herein provide a potential avenue to continue exploration of next generation NAMPT inhibitors to treat neoplasms in the clinic.
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Cianuros/administración & dosificación , Citocinas/antagonistas & inhibidores , Citocinas/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Fibrosarcoma/tratamiento farmacológico , Fibrosarcoma/metabolismo , Guanidinas/administración & dosificación , NAD/biosíntesis , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Nicotinamida Fosforribosiltransferasa/genética , Anilidas , Apoptosis/efectos de los fármacos , Apoptosis/genética , Arginina/análogos & derivados , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Fibrosarcoma/genética , Humanos , Mutación/genética , NAD/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Resultado del TratamientoRESUMEN
Muscle contraction upon nerve stimulation relies on excitation-contraction coupling (ECC) to promote the rapid and generalized release of calcium within myofibers. In skeletal muscle, ECC is performed by the direct coupling of a voltage-gated L-type Ca2+ channel (dihydropyridine receptor; DHPR) located on the T-tubule with a Ca2+ release channel (ryanodine receptor; RYR1) on the sarcoplasmic reticulum (SR) component of the triad. Here, we characterize a novel class of congenital myopathy at the morphological, molecular, and functional levels. We describe a cohort of 11 patients from 7 families presenting with perinatal hypotonia, severe axial and generalized weakness. Ophthalmoplegia is present in four patients. The analysis of muscle biopsies demonstrated a characteristic intermyofibrillar network due to SR dilatation, internal nuclei, and areas of myofibrillar disorganization in some samples. Exome sequencing revealed ten recessive or dominant mutations in CACNA1S (Cav1.1), the pore-forming subunit of DHPR in skeletal muscle. Both recessive and dominant mutations correlated with a consistent phenotype, a decrease in protein level, and with a major impairment of Ca2+ release induced by depolarization in cultured myotubes. While dominant CACNA1S mutations were previously linked to malignant hyperthermia susceptibility or hypokalemic periodic paralysis, our findings strengthen the importance of DHPR for perinatal muscle function in human. These data also highlight CACNA1S and ECC as therapeutic targets for the development of treatments that may be facilitated by the previous knowledge accumulated on DHPR.
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Canales de Calcio/genética , Canales de Calcio/metabolismo , Miotonía Congénita/genética , Miotonía Congénita/metabolismo , Adolescente , Adulto , Calcio/metabolismo , Canales de Calcio Tipo L , Células Cultivadas , Niño , Estudios de Cohortes , Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Células Musculares/metabolismo , Células Musculares/patología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Mutación , Miotonía Congénita/diagnóstico por imagen , Miotonía Congénita/patología , Fenotipo , Homología de Secuencia de Aminoácido , Adulto JovenRESUMEN
BACKGROUND: Aneuploidy can result in significant phenotypic changes, which can sometimes be selectively advantageous. For example, aneuploidy confers resistance to antifungal drugs in human pathogenic fungi. Aneuploidy has also been observed in invasive fungal and oomycete plant pathogens in the field. Environments conducive to the generation of aneuploids, the underlying genetic mechanisms, and the contribution of aneuploidy to invasiveness are underexplored. We studied phenotypic diversification and associated genome changes in Phytophthora ramorum, a highly destructive oomycete pathogen with a wide host-range that causes Sudden Oak Death in western North America and Sudden Larch Death in the UK. Introduced populations of the pathogen are exclusively clonal. In California, oak (Quercus spp.) isolates obtained from trunk cankers frequently exhibit host-dependent, atypical phenotypes called non-wild type (nwt), apparently without any host-associated population differentiation. Based on a large survey of genotypes from different hosts, we previously hypothesized that the environment in oak cankers may be responsible for the observed phenotypic diversification in P. ramorum. RESULTS: We show that both normal wild type (wt) and nwt phenotypes were obtained when wt P. ramorum isolates from the foliar host California bay (Umbellularia californica) were re-isolated from cankers of artificially-inoculated canyon live oak (Q. chrysolepis). We also found comparable nwt phenotypes in P. ramorum isolates from a bark canker of Lawson cypress (Chamaecyparis lawsoniana) in the UK; previously nwt was not known to occur in this pathogen population. High-throughput sequencing-based analyses identified major genomic alterations including partial aneuploidy and copy-neutral loss of heterozygosity predominantly in nwt isolates. Chromosomal breakpoints were located at or near transposons. CONCLUSION: This work demonstrates that major genome alterations of a pathogen can be induced by its host species. This is an undocumented type of plant-microbe interaction, and its contribution to pathogen evolution is yet to be investigated, but one of the potential collateral effects of nwt phenotypes may be host survival.
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Aneuploidia , Fenotipo , Phytophthora/genética , California , Variaciones en el Número de Copia de ADN , Elementos Transponibles de ADN , Duplicación de Gen , Perfilación de la Expresión Génica , Ligamiento Genético , Genotipo , Pérdida de Heterocigocidad , Enfermedades de las Plantas/microbiología , Polimorfismo de Nucleótido Simple , Quercus/microbiología , TranscriptomaRESUMEN
OBJECTIVE: To provide nationally representative data on the prevalence of anaemia, vitamin A and Fe deficiencies among pre-school age children (pre-SAC) and non-pregnant women of reproductive age (WRA), and on vitamin B12 and folate deficiencies in WRA, and the influence of inflammation on their interpretation. DESIGN: A cross-sectional survey to measure anthropometry, malaria parasitaemia and micronutrient status. Specifically, blood samples were analysed for Hb, plasma ferritin, soluble transferrin receptors, C-reactive protein, α1-acid glycoprotein, retinol-binding protein, vitamin B12 and folate. SETTING: Côte d'Ivoire in 2007. SUBJECTS: Nine hundred and twenty-eight WRA and 879 pre-SAC. RESULTS: In WRA, prevalence of Plasmodium parasitaemia (5 %) was low, but inflammation (34 %) was higher. Anaemia was a severe public health problem and prevalence differed by residency and eco-region. Inflammation-adjusted Fe deficiency was highest in urban areas (20 %). Nationally, folate deficiency was 86 %, higher in urban areas and varied by eco-region. Prevalence of vitamin B12 deficiency was low but higher in the rural areas and the north. Inflammation-adjusted vitamin A deficiency was very low (1 %). In pre-SAC, prevalence of inflammation (67 %) and Plasmodium parasites (25 %) was high; the latter was associated with poverty, rural residency and higher ferritin concentrations. Anaemia was classified as a severe public health problem (72 %), and was higher in rural areas (76 %) and the north (87 %). A quarter of pre-SAC suffered from vitamin A deficiency (inflammation-adjusted) and prevalence of undernutrition was high. CONCLUSIONS: Prevalence of inflammation, Plasmodium parasitaemia and micronutrient deficiencies were high in Côte d'Ivoire, particularly in pre-SAC. Nutritional interventions should be accompanied by strategies to reduce exposure to infections.
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Fenómenos Fisiológicos Nutricionales Infantiles , Enfermedades Carenciales/epidemiología , Fenómenos Fisiológicos Nutricionales del Lactante , Desnutrición/epidemiología , Fenómenos Fisiologicos Nutricionales Maternos , Micronutrientes/deficiencia , Adolescente , Adulto , Biomarcadores/sangre , Índice de Masa Corporal , Desarrollo Infantil , Fenómenos Fisiológicos Nutricionales Infantiles/etnología , Preescolar , Côte d'Ivoire/epidemiología , Estudios Transversales , Enfermedades Carenciales/sangre , Enfermedades Carenciales/etnología , Enfermedades Carenciales/fisiopatología , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante/etnología , Masculino , Desnutrición/sangre , Desnutrición/etnología , Desnutrición/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos/etnología , Micronutrientes/sangre , Persona de Mediana Edad , Encuestas Nutricionales , Prevalencia , Salud Rural/etnología , Índice de Severidad de la Enfermedad , Salud Urbana/etnología , Adulto JovenRESUMEN
Enzymatic saccharification is used to convert polysaccharides in lignocellulosic biomass to sugars which are then converted to ethanol or other bio-based fermentation products. The efficacy of commercial cellulase preparations can potentially increase if lytic polysaccharide monooxygenase (LPMO) is included. However, as LPMO requires both a reductant and an oxidant, such as molecular oxygen, a reevaluation of process configurations and conditions is warranted. Saccharification and fermentation of pretreated softwood was investigated in demonstration-scale experiments with 10 m3 bioreactors using an LPMO-containing cellulase preparation, a xylose-utilizing yeast, and either simultaneous saccharification and fermentation (SSF) or hybrid hydrolysis and fermentation (HHF) with a 24-hour or 48-hour initial phase and with 0.15 vvm aeration before addition of the yeast. The conditions used for HHF, especially with 48 h initial phase, resulted in better glucan conversion, but in poorer ethanol productivity and in poorer initial ethanol yield on consumed sugars than the SSF. In the SSF, hexose sugars such as glucose and mannose were consumed faster than xylose, but, in the end of the fermentation >90% of the xylose had been consumed. Chemical analysis of inhibitory pretreatment by-products indicated that the concentrations of heteroaromatic aldehydes (such as furfural), aromatic aldehydes, and an aromatic ketone decreased as a consequence of the aeration. This was attributed mainly to evaporation caused by the gas flow. The results indicate that further research is needed to fully exploit the advantages of LPMO without compromising fermentation conditions.
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Objective.Neuromodulation, particularly electrical stimulation, necessitates high spatial resolution to achieve artificial vision with high acuity. In epiretinal implants, this is hindered by the undesired activation of distal axons. Here, we investigate focal and axonal activation of retinal ganglion cells (RGCs) in epiretinal configuration for different sinusoidal stimulation frequencies.Approach.RGC responses to epiretinal sinusoidal stimulation at frequencies between 40 and 100 Hz were tested inex-vivophotoreceptor degenerated (rd10) isolated retinae. Experiments were conducted using a high-density CMOS-based microelectrode array, which allows to localize RGC cell bodies and axons at high spatial resolution.Main results.We report current and charge density thresholds for focal and distal axon activation at stimulation frequencies of 40, 60, 80, and 100 Hz for an electrode size with an effective area of 0.01 mm2. Activation of distal axons is avoided up to a stimulation amplitude of 0.23µA (corresponding to 17.3µC cm-2) at 40 Hz and up to a stimulation amplitude of 0.28µA (14.8µC cm-2) at 60 Hz. The threshold ratio between focal and axonal activation increases from 1.1 for 100 Hz up to 1.6 for 60 Hz, while at 40 Hz stimulation frequency, almost no axonal responses were detected in the tested intensity range. With the use of synaptic blockers, we demonstrate the underlying direct activation mechanism of the ganglion cells. Finally, using high-resolution electrical imaging and label-free electrophysiological axon tracking, we demonstrate the extent of activation in axon bundles.Significance.Our results can be exploited to define a spatially selective stimulation strategy avoiding axonal activation in future retinal implants, thereby solving one of the major limitations of artificial vision. The results may be extended to other fields of neuroprosthetics to achieve selective focal electrical stimulation.
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Retina , Prótesis Visuales , Retina/fisiología , Células Ganglionares de la Retina/fisiología , Microelectrodos , Axones/fisiología , Estimulación Eléctrica/métodosRESUMEN
With cancer as one of the leading causes of death worldwide, there is a need for the development of accurate, cost-effective, easy-to-use, and fast drug-testing assays. While the NCI 60 cell-line screening as the gold standard is based on a colorimetric assay, monitoring cells electrically constitutes a label-free and non-invasive tool to assess the cytotoxic effects of a chemotherapeutic treatment on cancer cells. For decades, impedance-based cellular assays extensively investigated various cell characteristics affected by drug treatment but lack spatiotemporal resolution. With progress in microelectrode fabrication, high-density Complementary Metal Oxide Semiconductor (CMOS)-based microelectrode arrays (MEAs) with subcellular resolution and time-continuous recording capability emerged as a potent alternative. In this article, we present a new cell adhesion noise (CAN)-based electrical imaging technique to expand CMOS MEA cell-biology applications: CAN spectroscopy enables drug screening quantification with single-cell spatial resolution. The chemotherapeutic agent 5-Fluorouracil exerts a cytotoxic effect on colorectal cancer (CRC) cells hampering cell proliferation and lowering cell viability. For proof-of-concept, we found sufficient accuracy and reproducibility for CAN spectroscopy compared to a commercially available standard colorimetric biological assay. This label-free, non-invasive, and fast electrical imaging technique complements standardized cancer screening methods with significant advances over established impedance-based approaches.
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This study examines the effects of news events related to the European Union-Vietnam Free Trade Agreement (EVFTA) on the Vietnam stock market from 2010 to 2020. We calculate sectoral abnormal returns prior to, during, and after announcements and find that the Vietnamese stock market is susceptible to these events. We discovered that the announcement had a negative impact on the market, which might diminish the effectiveness of the Agreement. The findings show that more than half of Vietnam's sectors had an immediate reaction to EVFTA announcements, with fourteen reacting negatively and six responding positively. Two of the ten events did not have any immediate impact on these industries but all events resulted in either early or delayed reactions. We also find market scepticism and major changes in the deal led to the emergence of a diamond risk structure. We run multiple robustness tests to account for market integration and other factors that may affect stock returns. In addition, we explore potential sectoral systematic risk changes following these occurrences using different ARCH-type models. These additional tests confirm the robustness of our findings.