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1.
FEBS Lett ; 598(7): 719-724, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38514456

RESUMEN

The diverse range of organizations contributing to the global research ecosystem is believed to enhance the overall quality and resilience of its output. Mid-sized autonomous research institutes, distinct from universities, play a crucial role in this landscape. They often lead the way in new research fields and experimental methods, including those in social and organizational domains, which are vital for driving innovation. The EU-LIFE alliance was established with the goal of fostering excellence by developing and disseminating best practices among European biomedical research institutes. As directors of the 15 EU-LIFE institutes, we have spent a decade comparing and refining our processes. Now, we are eager to share the insights we've gained. To this end, we have crafted this Charter, outlining 10 principles we deem essential for research institutes to flourish and achieve ground-breaking discoveries. These principles, detailed in the Charter, encompass excellence, independence, training, internationality and inclusivity, mission focus, technological advancement, administrative innovation, cooperation, societal impact, and public engagement. Our aim is to inspire the establishment of new institutes that adhere to these principles and to raise awareness about their significance. We are convinced that they should be viewed a crucial component of any national and international innovation strategies.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Investigación Biomédica , Academias e Institutos
2.
Cell Rep ; 43(4): 113998, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38551960

RESUMEN

RNase L is an endoribonuclease of higher vertebrates that functions in antiviral innate immunity. Interferons induce oligoadenylate synthetase enzymes that sense double-stranded RNA of viral origin leading to the synthesis of 2',5'-oligoadenylate (2-5A) activators of RNase L. However, it is unknown precisely how RNase L remodels the host cell transcriptome. To isolate effects of RNase L from other effects of double-stranded RNA or virus, 2-5A is directly introduced into cells. Here, we report that RNase L activation by 2-5A causes a ribotoxic stress response involving the MAP kinase kinase kinase (MAP3K) ZAKα, MAP2Ks, and the stress-activated protein kinases JNK and p38α. RNase L activation profoundly alters the transcriptome by widespread depletion of mRNAs associated with different cellular functions but also by JNK/p38α-stimulated induction of inflammatory genes. These results show that the 2-5A/RNase L system triggers a protein kinase cascade leading to proinflammatory signaling and apoptosis.


Asunto(s)
Endorribonucleasas , Inmunidad Innata , Endorribonucleasas/metabolismo , Endorribonucleasas/genética , Humanos , Nucleótidos de Adenina/metabolismo , Oligorribonucleótidos/metabolismo , Animales , Estrés Fisiológico , Transcriptoma/genética , ARN Bicatenario/metabolismo
3.
Sci Transl Med ; 16(733): eadi0944, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38324637

RESUMEN

Allergen-specific immunoglobulin E (IgE) antibodies mediate pathology in diseases such as allergic rhinitis and food allergy. Memory B cells (MBCs) contribute to circulating IgE by regenerating IgE-producing plasma cells upon allergen encounter. Here, we report a population of type 2-polarized MBCs defined as CD23hi, IL-4Rαhi, and CD32low at both the transcriptional and surface protein levels. These MBC2s are enriched in IgG1- and IgG4-expressing cells while constitutively expressing germline transcripts for IgE. Allergen-specific B cells from patients with allergic rhinitis and food allergy were enriched in MBC2s. Furthermore, MBC2s generated allergen-specific IgE during sublingual immunotherapy, thereby identifying these cells as a major reservoir for IgE. The identification of MBC2s provides insights into the maintenance of IgE memory, which is detrimental in allergic diseases but could be beneficial in protection against venoms and helminths.


Asunto(s)
Hipersensibilidad a los Alimentos , Rinitis Alérgica Estacional , Rinitis Alérgica , Humanos , Rinitis Alérgica Estacional/metabolismo , Células B de Memoria , Alérgenos , Inmunoglobulina E , Inmunoglobulina G
4.
Science ; 382(6675): eadf3208, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38060659

RESUMEN

The ribotoxic stress response (RSR) is a signaling pathway in which the p38- and c-Jun N-terminal kinase (JNK)-activating mitogen-activated protein kinase kinase kinase (MAP3K) ZAKα senses stalling and/or collision of ribosomes. Here, we show that reactive oxygen species (ROS)-generating agents trigger ribosomal impairment and ZAKα activation. Conversely, zebrafish larvae deficient for ZAKα are protected from ROS-induced pathology. Livers of mice fed a ROS-generating diet exhibit ZAKα-activating changes in ribosomal elongation dynamics. Highlighting a role for the RSR in metabolic regulation, ZAK-knockout mice are protected from developing high-fat high-sugar (HFHS) diet-induced blood glucose intolerance and liver steatosis. Finally, ZAK ablation slows animals from developing the hallmarks of metabolic aging. Our work highlights ROS-induced ribosomal impairment as a physiological activation signal for ZAKα that underlies metabolic adaptation in obesity and aging.


Asunto(s)
Envejecimiento , MAP Quinasa Quinasa Quinasa 3 , Obesidad , Especies Reactivas de Oxígeno , Ribosomas , Estrés Fisiológico , Animales , Ratones , Envejecimiento/metabolismo , MAP Quinasa Quinasa Quinasa 3/genética , MAP Quinasa Quinasa Quinasa 3/metabolismo , Obesidad/metabolismo , Biosíntesis de Proteínas , Especies Reactivas de Oxígeno/metabolismo , Ribosomas/metabolismo , Pez Cebra , Ratones Noqueados
5.
Cell Death Dis ; 14(7): 467, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-37495584

RESUMEN

Impairment of protein translation can cause stalling and collision of ribosomes and is a signal for the activation of ribosomal surveillance and rescue pathways. Despite clear evidence that ribosome collision occurs stochastically at a cellular and organismal level, physiologically relevant sources of such aberrations are poorly understood. Here we show that a burst of the cellular signaling molecule nitric oxide (NO) reduces translational activity and causes ribosome collision in human cell lines. This is accompanied by activation of the ribotoxic stress response, resulting in ZAKα-mediated activation of p38 and JNK kinases. In addition, NO production is associated with ZNF598-mediated ubiquitination of the ribosomal protein RPS10 and GCN2-mediated activation of the integrated stress response, which are well-described responses to the collision of ribosomes. In sum, our work implicates a novel role of NO as an inducer of ribosome collision and activation of ribosomal surveillance mechanisms in human cells.


Asunto(s)
Óxido Nítrico , Ribosomas , Humanos , Óxido Nítrico/metabolismo , Ribosomas/metabolismo , Biosíntesis de Proteínas , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Ubiquitinación , Proteínas Portadoras/metabolismo
6.
Dev Cell ; 58(17): 1593-1609.e9, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37473757

RESUMEN

Translational regulation impacts both pluripotency maintenance and cell differentiation. To what degree the ribosome exerts control over this process remains unanswered. Accumulating evidence has demonstrated heterogeneity in ribosome composition in various organisms. 2'-O-methylation (2'-O-me) of rRNA represents an important source of heterogeneity, where site-specific alteration of methylation levels can modulate translation. Here, we examine changes in rRNA 2'-O-me during mouse brain development and tri-lineage differentiation of human embryonic stem cells (hESCs). We find distinct alterations between brain regions, as well as clear dynamics during cortex development and germ layer differentiation. We identify a methylation site impacting neuronal differentiation. Modulation of its methylation levels affects ribosome association of the fragile X mental retardation protein (FMRP) and is accompanied by an altered translation of WNT pathway-related mRNAs. Together, these data identify ribosome heterogeneity through rRNA 2'-O-me during early development and differentiation and suggest a direct role for ribosomes in regulating translation during cell fate acquisition.


Asunto(s)
ARN Ribosómico , Ribosomas , Humanos , Animales , Ratones , Metilación , Ribosomas/metabolismo , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , Diferenciación Celular , Neurogénesis/genética , Proteínas Ribosómicas/metabolismo
7.
Cells ; 12(7)2023 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-37048063

RESUMEN

It is well established that mutations in the canonical WNT-signalling pathway play a major role in various cancers. Critical to developing new therapeutic strategies is understanding which cancers are driven by WNT pathway activation and at what level these mutations occur within the pathway. Some cancers harbour mutations in genes whose protein products operate at the receptor level of the WNT pathway. For instance, tumours with RNF43 or RSPO mutations, still require exogenous WNT ligands to drive WNT signalling (ligand-dependent mutations). Conversely, mutations within the cytoplasmic segment of the Wnt pathway, such as in APC and CTNNB1, lead to constitutive WNT pathway activation even in the absence of WNT ligands (ligand-independent). Here, we review the predominant driving mutations found in cancer that lead to WNT pathway activation, as well as explore some of the therapeutic interventions currently available against tumours harbouring either ligand-dependent or ligand-independent mutations. Finally, we discuss a potentially new therapeutic avenue by targeting the translational apparatus downstream from WNT signalling.


Asunto(s)
Neoplasias , Vía de Señalización Wnt , Humanos , Vía de Señalización Wnt/genética , Ligandos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/metabolismo , Mutación/genética
8.
Sci Rep ; 13(1): 2974, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36806717

RESUMEN

FUS is a multifunctional protein involved in many aspects of RNA metabolism, including transcription, splicing, translation, miRNA processing, and replication-dependent histone gene expression. In this work, we show that FUS depletion results in the differential expression of numerous small nucleolar RNAs (snoRNAs) that guide 2'-O methylation (2'-O-Me) and pseudouridylation of specific positions in ribosomal RNAs (rRNAs) and small nuclear RNAs (snRNAs). Using RiboMeth-seq and HydraPsiSeq for the profiling of 2'-O-Me and pseudouridylation status of rRNA species, we demonstrated considerable hypermodification at several sites in HEK293T and SH-SY5Y cells with FUS knockout (FUS KO) compared to wild-type cells. We observed a similar direction of changes in rRNA modification in differentiated SH-SY5Y cells with the FUS mutation (R495X) related to the severe disease phenotype of amyotrophic lateral sclerosis (ALS). Furthermore, the pattern of modification of some rRNA positions was correlated with the abundance of corresponding guide snoRNAs in FUS KO and FUS R495X cells. Our findings reveal a new role for FUS in modulating the modification pattern of rRNA molecules, that in turn might generate ribosome heterogeneity and constitute a fine-tuning mechanism for translation efficiency/fidelity. Therefore, we suggest that increased levels of 2'-O-Me and pseudouridylation at particular positions in rRNAs from cells with the ALS-linked FUS mutation may represent a possible new translation-related mechanism that underlies disease development and progression.


Asunto(s)
Esclerosis Amiotrófica Lateral , Neuroblastoma , Humanos , ARN Nucleolar Pequeño/genética , Células HEK293 , ARN Ribosómico/genética , Proteína FUS de Unión a ARN/genética
9.
EMBO J ; 42(4): e112835, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36695748

RESUMEN

In this commentary, Sonne-Hansen and colleagues argue that research leaders and organizations should encourage more "theory-guessing" by budding young scientists, rather than incentivizing safe mainstream research.


Asunto(s)
Antídotos , Creatividad
10.
Cell Rep ; 39(6): 110793, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35545054

RESUMEN

Ribosomopathies constitute a range of disorders associated with defective protein synthesis mainly affecting hematopoietic stem cells (HSCs) and erythroid development. Here, we demonstrate that deletion of poly-pyrimidine-tract-binding protein 1 (PTBP1) in the hematopoietic compartment leads to the development of a ribosomopathy-like condition. Specifically, loss of PTBP1 is associated with decreases in HSC self-renewal, erythroid differentiation, and protein synthesis. Consistent with its function as a splicing regulator, PTBP1 deficiency results in splicing defects in hundreds of genes, and we demonstrate that the up-regulation of a specific isoform of CDC42 partly mimics the protein-synthesis defect associated with loss of PTBP1. Furthermore, PTBP1 deficiency is associated with a marked defect in ribosome biogenesis and a selective reduction in the translation of mRNAs encoding ribosomal proteins. Collectively, this work identifies PTBP1 as a key integrator of ribosomal functions and highlights the broad functional repertoire of RNA-binding proteins.


Asunto(s)
Células Madre Hematopoyéticas , Ribosomas , Eritrocitos/metabolismo , Eritropoyesis , Células Madre Hematopoyéticas/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Proteína de Unión al Tracto de Polipirimidina/genética , Proteína de Unión al Tracto de Polipirimidina/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo
11.
Phys Chem Chem Phys ; 24(17): 10318-10324, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35437545

RESUMEN

Coronene (C24H12), a charge transfer complex with low-cost and high-performance energy storage, has recently attracted attention as a model molecule of graphene nano-flakes (GNFs). The stacking structures of the trimer radical cation correlate strongly with the conduction states of the GNFs. In the present paper, the structures and electronic states of the monomer, dimer and trimer radical cations of coronene were investigated by means of density functional theory calculations. In particular, the proton hyperfine coupling constants of these species were determined. The radical cation of coronene+ (monomer) showed two structures corresponding to the 2Au and 2B3u states due to the Jahn-Teller effect. The 2Au state was more stable than the 2B3u state, although the energy difference between the two states was only 0.03 kcal mol-1. The dimer and trimer radical cations took stacking structures distorted from a full overlap structure. The intermolecular distances of the molecular planes were 3.602 Å (dimer) and 3.564 and 3.600 Å (trimer). The binding energies of the dimer and trimer were calculated to be 8.7 and 13.3 kcal mol-1, respectively. The spin density was equivalently distributed on both coronene planes in the dimer cation. In contrast, the central plane in the trimer cation had a larger spin density, ρ = 0.72, than the upper and lower planes, both with ρ = 0.14. The proton hyperfine coupling constants calculated from these structures and the electronic states of the monomer, dimer, and trimer radical cations of coronene were in excellent agreement with previous ESR spectra of coronene radical cations. The structures and electronic states of (coronene)n+ (n = 1-3) were discussed on the basis of the theoretical results.

12.
Trends Biochem Sci ; 47(1): 66-81, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34312084

RESUMEN

The conceptual origins of ribosome specialization can be traced back to the earliest days of molecular biology. Yet, this field has only recently begun to gather momentum, with numerous studies identifying distinct heterogeneous ribosome populations across multiple species and model systems. It is proposed that some of these compositionally distinct ribosomes may be functionally specialized and able to regulate the translation of specific mRNAs. Identification and functional characterization of specialized ribosomes has the potential to elucidate a novel layer of gene expression control, at the level of translation, where the ribosome itself is a key regulatory player. In this review, we discuss different sources of ribosome heterogeneity, evidence for ribosome specialization, and also the future directions of this exciting field.


Asunto(s)
Biosíntesis de Proteínas , Proteínas Ribosómicas , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Ribosómico/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/genética , Ribosomas/metabolismo
13.
Blood ; 139(2): 245-255, 2022 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-34359076

RESUMEN

Novel therapies for the treatment of acute myeloid leukemia (AML) are urgently needed, because current treatments do not cure most patients with AML. We report a domain-focused, kinome-wide CRISPR-Cas9 screening that identified protein kinase targets for the treatment of AML, which led to the identification of Rio-kinase 2 (RIOK2) as a potential novel target. Loss of RIOK2 led to a decrease in protein synthesis and to ribosomal instability followed by apoptosis in leukemic cells, but not in fibroblasts. Moreover, the ATPase function of RIOK2 was necessary for cell survival. When a small-molecule inhibitor was used, pharmacological inhibition of RIOK2 similarly led to loss of protein synthesis and apoptosis and affected leukemic cell growth in vivo. Our results provide proof of concept for targeting RIOK2 as a potential treatment of patients with AML.


Asunto(s)
Leucemia Mieloide Aguda , Inhibidores de Proteínas Quinasas , Animales , Ratones , Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas CRISPR-Cas , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Terapia Molecular Dirigida , Biosíntesis de Proteínas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología
14.
J Microbiol Methods ; 192: 106381, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34822946

RESUMEN

The improvement of cell enumeration methods for the counting of Escherichia coli (E. coli) is important as E. coli gains in popularity as a basis for biopharmaceutical applications. In the biopharmaceutical industry, enumerating, characterizing, and dosing the accurate number of cells is imperative. In this work, we demonstrate the utilization of a chip-based image cytometer using a thin-gap, low volume counting chamber consumable to directly enumerate E. coli in bright field and fluorescence, and measure their viability using SYTOX™ Green. The total E. coli particles can be counted accurately label-free by adjusting the focus and targeting the linear range of the instrument. The E. coli are stained with SYTOX™ Green to count the membrane-compromised dead bacterial cells in the green fluorescence channel, while the total cells are counted using the bright field channel. Optimization of the system settings, image focus, cell counting range, and staining conditions have yielded a precise, rapid, and accurate E. coli cell enumeration and viability measurement.


Asunto(s)
Carga Bacteriana/métodos , Escherichia coli/citología , Escherichia coli/crecimiento & desarrollo , Citometría de Imagen/métodos , Recuento de Colonia Microbiana/métodos , Microscopía Fluorescente , Compuestos Orgánicos/farmacología , Coloración y Etiquetado/métodos
15.
Nat Struct Mol Biol ; 28(11): 889-899, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34759377

RESUMEN

Ribosomes are complex ribozymes that interpret genetic information by translating messenger RNA (mRNA) into proteins. Natural variation in ribosome composition has been documented in several organisms and can arise from several different sources. A key question is whether specific control over ribosome heterogeneity represents a mechanism by which translation can be regulated. We used RiboMeth-seq to demonstrate that differential 2'-O-methylation of ribosomal RNA (rRNA) represents a considerable source of ribosome heterogeneity in human cells, and that modification levels at distinct sites can change dynamically in response to upstream signaling pathways, such as MYC oncogene expression. Ablation of one prominent methylation resulted in altered translation of select mRNAs and corresponding changes in cellular phenotypes. Thus, differential rRNA 2'-O-methylation can give rise to ribosomes with specialized function. This suggests a broader mechanism where the specific regulation of rRNA modification patterns fine tunes translation.


Asunto(s)
Biosíntesis de Proteínas/fisiología , Proteínas Proto-Oncogénicas c-myc/genética , Procesamiento Postranscripcional del ARN/fisiología , ARN Ribosómico/metabolismo , Ribosomas/metabolismo , Línea Celular Tumoral , Células HeLa , Humanos , Metilación , Procesamiento Proteico-Postraduccional/fisiología , Proteínas Proto-Oncogénicas c-myc/biosíntesis , ARN Mensajero/genética
16.
Nat Commun ; 12(1): 2459, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33911076

RESUMEN

Oncogene-induced senescence provides a barrier against malignant transformation. However, it can also promote cancer through the secretion of a plethora of factors released by senescent cells, called the senescence associated secretory phenotype (SASP). We have previously shown that in proliferating cells, nuclear lncRNA MIR31HG inhibits p16/CDKN2A expression through interaction with polycomb repressor complexes and that during BRAF-induced senescence, MIR31HG is overexpressed and translocates to the cytoplasm. Here, we show that MIR31HG regulates the expression and secretion of a subset of SASP components during BRAF-induced senescence. The SASP secreted from senescent cells depleted for MIR31HG fails to induce paracrine invasion without affecting the growth inhibitory effect. Mechanistically, MIR31HG interacts with YBX1 facilitating its phosphorylation at serine 102 (p-YBX1S102) by the kinase RSK. p-YBX1S102 induces IL1A translation which activates the transcription of the other SASP mRNAs. Our results suggest a dual role for MIR31HG in senescence depending on its localization and points to the lncRNA as a potential therapeutic target in the treatment of senescence-related pathologies.


Asunto(s)
Envejecimiento/genética , Transformación Celular Neoplásica/genética , Senescencia Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , ARN Largo no Codificante/genética , Línea Celular , Proliferación Celular/genética , Transformación Celular Neoplásica/patología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Humanos , Neoplasias/genética , Neoplasias/patología , Fosforilación , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Proteína 1 de Unión a la Caja Y/metabolismo
17.
J Magn Reson ; 325: 106956, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33684889

RESUMEN

The analysis of single crystal electron magnetic resonance (EMR) data has traditionally been performed using software in programming languages that are difficult to update, are not easily available, or are obsolete. By using a modern script-language with tools for the analysis and graphical display of the data, three MatLab® codes were prepared to compute the g, zero-field splitting (zfs) and hyperfine coupling (hfc) tensors from roadmaps obtained by EPR or ENDOR measurements in three crystal planes. Schonland's original method was used to compute the g- and hfc -tensors by a least-squares fit to the experimental data in each plane. The modifications required for the analysis of the zfs of radical pairs with S = 1 were accounted for. A non-linear fit was employed in a second code to obtain the hfc -tensor from EPR measurements, taking the nuclear Zeeman interaction of an I = ½ nucleus into account. A previously developed method to calculate the g- and hfc -tensors by a simultaneous linear fit to all data was used in the third code. The validity of the methods was examined by comparison with results obtained experimentally, and by roadmaps computed by exact diagonalization. The probable errors were estimated using functions for regression analysis available in MatLab. The software will be published at https://doi.org/10.17632/ps24sw95gz.1, Input and output examples presented in this work can also be downloaded from https://old.liu.se/simarc/downloads?l=en.

18.
J Pharm Sci ; 110(2): 619-626, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33212163

RESUMEN

In this commentary, we will provide a high-level introduction into LC-MS product characterization methodologies deployed throughout biopharmaceutical development. The ICH guidelines for early and late phase filings is broad so that it is applicable to diverse biotherapeutic products in the clinic and industry pipelines. This commentary is meant to address areas of protein primary sequence confirmation and sequence variant analysis where ambiguity exists in industry on the specific scope of work that is needed to fulfill the general guidance that is given in sections Q5b and Q6b. This commentary highlights the discussion and outcomes of two recent workshops centering on the application of LC-MS to primary structure confirmation and sequence variant analysis (SVA) that were held at the 2018 and 2019 CASSS Practical Applications of Mass Spectrometry in the Biotechnology Industry Symposia in San Francisco, CA and Chicago, IL, respectively. Recommendations from the conferences fall into two distinct but related areas; 1) consolidation of opinions amongst industry stakeholders on the specific definitions of peptide mapping and peptide sequencing for primary structure confirmation and the technologies used for both, as they relate to regulatory expectations and submissions and 2) development of fit-for-purpose strategy to define appropriate assay controls in SVA experiments.


Asunto(s)
Péptidos , Secuencia de Aminoácidos , Cromatografía Liquida , Espectrometría de Masas , Mapeo Peptídico
19.
Brain Commun ; 2(2): fcaa147, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33225277

RESUMEN

Levodopa-induced dyskinesia gradually emerges during long-term dopamine therapy, causing major disability in patients with Parkinson disease. Using pharmacodynamic functional MRI, we have previously shown that the intake of levodopa triggers an excessive activation of the pre-supplementary motor area in Parkinson disease patients with peak-of-dose dyskinesia. In this pre-registered, interventional study, we tested whether the abnormal responsiveness of the pre-supplementary motor area to levodopa may constitute a 'stimulation target' for treating dyskinesia. A gender-balanced group of 17 Parkinson disease patients with peak-of-dose dyskinesia received 30 min of robot-assisted repetitive transcranial magnetic stimulation, after they had paused their anti-Parkinson medication. Real-repetitive transcranial magnetic stimulation at 100% or sham-repetitive transcranial magnetic stimulation at 30% of individual resting corticomotor threshold of left first dorsal interosseous muscle was applied on separate days in counterbalanced order. Following repetitive transcranial magnetic stimulation, patients took 200 mg of oral levodopa and underwent functional MRI to map brain activity, while they performed the same go/no-go task as in our previous study. Blinded video assessment revealed that real-repetitive transcranial magnetic stimulation delayed the onset of dyskinesia and reduced its severity relative to sham-repetitive transcranial magnetic stimulation. Individual improvement in dyskinesia severity scaled linearly with the modulatory effect of real-repetitive transcranial magnetic stimulation on task-related activation in the pre-supplementary motor area. Stimulation-induced delay in dyskinesia onset correlated positively with the induced electrical field strength in the pre-supplementary motor area. Our results provide converging evidence that the levodopa-triggered increase in pre-supplementary motor area activity plays a causal role in the pathophysiology of peak-of-dose dyskinesia and constitutes a promising cortical target for brain stimulation therapy.

20.
Am J Physiol Regul Integr Comp Physiol ; 319(6): R712-R723, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33074013

RESUMEN

The menopausal transition is associated with increased prevalence of hypertension, and in time, postmenopausal women (PMW) will exhibit a cardiovascular disease risk score similar to male counterparts. Hypertension is associated with vascular dysfunction, but whether hypertensive (HYP) PMW have blunted nitric oxide (NO)-mediated leg vasodilator responsiveness and whether this is reversible by high-intensity training (HIT) is unknown. To address these questions, we examined the leg vascular conductance (LVC) in response to femoral infusion of acetylcholine (ACh) and sodium nitroprusside (SNP) and skeletal muscle markers of oxidative stress and NO bioavailability before and after HIT in PMW [12.9 ± 6.0 (means ± SD) years since last menstrual cycle]. We hypothesized that ACh- and SNP-induced LVC responsiveness was reduced in hypertensive compared with normotensive (NORM) PMW and that 10 wk of HIT would reverse the blunted LVC response and decrease blood pressure (BP). Nine hypertensive (HYP (clinical systolic/diastolic BP, 149 ± 11/91 ± 83 mmHg) and eight normotensive (NORM (122 ± 13/75 ± 8 mmHg) PMW completed 10 wk of biweekly small-sided floorball training (4-5 × 3-5 min interspersed by 1-3-min rest periods). Before training, the SNP-induced change in LVC was lower (P < 0.05) in HYP compared with in NORM. With training, the ACh- and SNP-induced change in LVC at maximal infusion rates, i.e., 100 and 6 µg·min-1·kg leg mass-1, respectively, improved (P < 0.05) in HYP only. Furthermore, training decreased (P < 0.05) clinical systolic/diastolic BP (-15 ± 11/-9 ± 7 mmHg) in HYP and systolic BP (-10 ± 9 mmHg) in NORM. Thus, the SNP-mediated LVC responsiveness was blunted in HYP PMW and reversed by a period of HIT that was associated with a marked decrease in clinical BP.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Hipertensión/terapia , Extremidad Inferior/irrigación sanguínea , Óxido Nítrico/metabolismo , Posmenopausia , Vasodilatación , Acetilcolina/administración & dosificación , Factores de Edad , Anciano , Femenino , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Persona de Mediana Edad , Donantes de Óxido Nítrico/administración & dosificación , Nitroprusiato/administración & dosificación , Estrés Oxidativo , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento , Vasodilatación/efectos de los fármacos , Vasodilatadores/administración & dosificación
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