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1.
Cell Death Discov ; 10(1): 191, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664396

RESUMEN

Inflammasome assembly is a potent mechanism responsible for the host protection against pathogens, including viruses. When compromised, it can allow viral replication, while when disrupted, it can perpetuate pathological responses by IL-1 signaling and pyroptotic cell death. SARS-CoV-2 infection was shown to activate inflammasome in the lungs of COVID-19 patients, however, potential mechanisms responsible for this response are not fully elucidated. In this study, we investigated the effects of ORF3a, E and M SARS-CoV-2 viroporins in the inflammasome activation in major populations of alveolar sentinel cells: macrophages, epithelial and endothelial cells. We demonstrated that each viroporin is capable of activation of the inflammasome in macrophages to trigger pyroptosis-like cell death and IL-1α release from epithelial and endothelial cells. Small molecule NLRP3 inflammasome inhibitors reduced IL-1 release but weakly affected the pyroptosis. Importantly, we discovered that while SARS-CoV-2 could not infect the pulmonary microvascular endothelial cells it induced IL-1α and IL-33 release. Together, these findings highlight the essential role of macrophages as the major inflammasome-activating cell population in the lungs and point to endothelial cell expressed IL-1α as a potential novel component driving the pulmonary immunothromobosis in COVID-19.

2.
Cancer Immunol Res ; 12(4): 427-439, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38315788

RESUMEN

Recent research indicates that gut microbiota may be vital in the advancement of melanoma. In this study, we found that melanoma patients exhibited a distinct gut mycobiota structure compared with healthy participants. Candida albicans, Candida dubliniensis, and Neurospora crassa were more abundant in samples from patients with melanoma, whereas Saccharomyces cerevisiae and Debaryomyces hansenii were less abundant. During anti-PD-1 treatment, the relative amount of Malassezia restricta and C. albicans increased. A higher level of Saccharomyces paradoxus was associated with a positive response to anti-PD-1 treatment, whereas a higher level of Tetrapisispora blattae was associated with a lack of clinical benefits. High levels of M. restricta and C. albicans, elevated serum lactate dehydrogenase, and being overweight were linked to increased risk of melanoma progression and poorer response to anti-PD-1 treatment. Thus, this study has revealed melanoma-associated mycobiome dysbiosis, characterized by altered fungal composition and fungi species associated with a higher risk of melanoma progression, identifying a role for the gut mycobiome in melanoma progression.


Asunto(s)
Microbioma Gastrointestinal , Melanoma , Micobioma , Humanos , Hongos/fisiología , Disbiosis/microbiología , Melanoma/tratamiento farmacológico , Saccharomyces cerevisiae
3.
J Neurotrauma ; 41(9-10): 1223-1239, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38318802

RESUMEN

A significant problem in the diagnosis and management of traumatic spinal cord injury (tSCI) is the heterogeneity of secondary injury and the prediction of neurological outcome. Imaging biomarkers specific to myelin loss and inflammation after tSCI would enable detailed assessment of the pathophysiological processes underpinning secondary damage to the cord. Such biomarkers could be used to biologically stratify injury severity and better inform prognosis for neurological recovery. While much work has been done to establish magnetic resonance imaging (MRI) biomarkers for SCI in animal models, the relationship between imaging findings and the underlying pathology has been difficult to discern in human tSCI because of the paucity of human spinal cord tissue. We utilized post-mortem spinal cords from individuals who had a tSCI to examine this relationship by performing ex vivo MRI scans before histological analysis. We investigated the correlation between the histological distribution of myelin loss and inflammatory cells in the injured spinal cord and a number of myelin and inflammation-sensitive MRI measures: myelin water fraction (MWF), inhomogeneous magnetization transfer ratio (ihMTR), and diffusion tensor and diffusion kurtosis imaging-derived fractional anisotropy (FA) and axial, radial, and mean diffusivity (AD, RD, MD). The histological features were analyzed by staining with Luxol Fast Blue (LFB) for myelin lipids and Class II major histocompatibility complex (Class II MHC) and CD68 for microglia and macrophages. Both MWF and ihMTR were strongly correlated with LFB staining for myelin, supporting the use of both as biomarkers for myelin loss after SCI. A decrease in ihMTR was also correlated with the presence of Class II MHC positive immune cells. FA and RD correlated with both Class II MHC and CD68 and may therefore be useful biomarkers for inflammation after tSCI. Our work demonstrates the utility of advanced MRI techniques sensitive to biological tissue damage after tSCI, which is an important step toward using these MRI techniques in the clinic to aid in decision-making.


Asunto(s)
Biomarcadores , Imagen por Resonancia Magnética , Traumatismos de la Médula Espinal , Traumatismos de la Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/metabolismo , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Biomarcadores/análisis , Biomarcadores/metabolismo , Femenino , Persona de Mediana Edad , Anciano , Adulto , Imagen de Difusión Tensora/métodos , Vaina de Mielina/patología , Vaina de Mielina/metabolismo , Anciano de 80 o más Años , Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Médula Espinal/metabolismo
4.
Nucleic Acids Res ; 52(4): 1628-1644, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38261968

RESUMEN

A growing body of evidence indicates an important role of miRNAs in cancer; however, there is no definitive, convenient-to-use list of cancer-related miRNAs or miRNA genes that may serve as a reference for analyses of miRNAs in cancer. To this end, we created a list of 165 cancer-related miRNA genes called the Cancer miRNA Census (CMC). The list is based on a score, built on various types of functional and genetic evidence for the role of particular miRNAs in cancer, e.g. miRNA-cancer associations reported in databases, associations of miRNAs with cancer hallmarks, or signals of positive selection of genetic alterations in cancer. The presence of well-recognized cancer-related miRNA genes, such as MIR21, MIR155, MIR15A, MIR17 or MIRLET7s, at the top of the CMC ranking directly confirms the accuracy and robustness of the list. Additionally, to verify and indicate the reliability of CMC, we performed a validation of criteria used to build CMC, comparison of CMC with various cancer data (publications and databases), and enrichment analyses of biological pathways and processes such as Gene Ontology or DisGeNET. All validation steps showed a strong association of CMC with cancer/cancer-related processes confirming its usefulness as a reference list of miRNA genes associated with cancer.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , MicroARNs , Neoplasias , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias/genética , Reproducibilidad de los Resultados
6.
Mol Brain ; 16(1): 76, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37924146

RESUMEN

Familial hemiplegic migraine type-1 (FHM-1) is a form of migraine with aura caused by mutations in the P/Q-type (Cav2.1) voltage-gated calcium channel. Pregabalin, used clinically in the treatment of chronic pain and epilepsy, inhibits P/Q-type calcium channel activity and recent studies suggest that it may have potential for the treatment of migraine. Spreading Depolarization (SD) is a neurophysiological phenomenon that can occur during migraine with aura by propagating a wave of silenced neuronal function through cortex and sometimes subcortical brain structures. Here, utilizing an optogenetic stimulation technique optimized to allow for non-invasive initiation of cortical SD, we demonstrate that chronic pregabalin administration [12 mg/kg/day (s.c.)] in vivo increased the threshold for cortical spreading depolarization in transgenic mice harboring the clinically-relevant Cav2.1S218L mutation (S218L). In addition, chronic pregabalin treatment limited subcortical propagation of recurrent spreading depolarization events to the striatum and hippocampus in both wild-type and S218L mice. To examine contributing underlying mechanisms of action of chronic pregabalin, we performed whole-cell patch-clamp electrophysiology in CA1 neurons in ex vivo brain slices from mice treated with chronic pregabalin vs vehicle. In WT mice, chronic pregabalin produced a decrease in spontaneous excitatory postsynaptic current (sEPSC) amplitude with no effect on frequency. In contrast, in S218L mice chronic pregabalin produced an increase in sEPSC amplitude and decreased frequency. These electrophysiological findings suggest that in FHM-1 mice chronic pregabalin acts through both pre- and post-synaptic mechanisms in CA1 hippocampal neurons to elicit FHM-1 genotype-specific inhibitory action. The results highlight the potential of chronic pregabalin to limit recurrent SD to subcortical brain structures during pathophysiological events in both the genetically-normal and FHM-1 brain. The work further provides insights into FHM-1 pathophysiology and the potential for chronic pregabalin treatment to prevent SD in migraineurs.


Asunto(s)
Trastornos Migrañosos , Migraña con Aura , Ratones , Animales , Migraña con Aura/tratamiento farmacológico , Migraña con Aura/genética , Pregabalina/farmacología , Pregabalina/uso terapéutico , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/genética , Ratones Transgénicos , Hipocampo
7.
Cells ; 12(20)2023 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-37887293

RESUMEN

ERH is a 100 to about 110 aa nuclear protein with unique primary and three-dimensional structures that are very conserved from simple eukaryotes to humans, albeit some species have lost its gene, with most higher fungi being a noteworthy example. Initially, studies on Drosophila melanogaster implied its function in pyrimidine metabolism. Subsequently, research on Xenopus laevis suggested that it acts as a transcriptional repressor. Finally, studies in humans pointed to a role in pre-mRNA splicing and in mitosis but further research, also in Caenorhabditis elegans and Schizosaccharomyces pombe, demonstrated its much broader activity, namely involvement in the biogenesis of mRNA, and miRNA, piRNA and some other ncRNAs, and in repressive heterochromatin formation. ERH interacts with numerous, mostly taxon-specific proteins, like Mmi1 and Mei2 in S. pombe, PID-3/PICS-1, TOST-1 and PID-1 in C. elegans, and DGCR8, CIZ1, PDIP46/SKAR and SAFB1/2 in humans. There are, however, some common themes in this wide range of processes and partners, such as: (a) ERH homodimerizes to form a scaffold for several complexes involved in the metabolism of nucleic acids, (b) all these RNAs are RNA polymerase II transcripts, (c) pre-mRNAs, whose splicing depends on ERH, are enriched in transcripts of DNA damage response and DNA metabolism genes, and (d) heterochromatin is formed to silence unwanted transcription, e.g., from repetitive elements. Thus, it seems that ERH has been adopted for various pathways that serve to maintain genome integrity.


Asunto(s)
Proteínas de Ciclo Celular , Empalme del ARN , Factores de Transcripción , Animales , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Drosophila melanogaster/genética , Heterocromatina/metabolismo , MicroARNs/metabolismo , Mitosis/genética , Proteínas de Unión al ARN/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Factores de Transcripción/genética , Proteínas de Ciclo Celular/genética
8.
mSystems ; 8(2): e0098622, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-36786595

RESUMEN

Recent studies revealed a significant role of the gut fungal community in human health. Here, we investigated the content and variation of gut mycobiota among subjects from the European population. We explored the interplay between gut fungi and various host-related sociodemographic, lifestyle, health, and dietary factors. The study included 923 participants. Fecal DNA samples were analyzed by whole-metagenome high-throughput sequencing. Subsequently, fungi taxonomic profiles were determined and accompanied by computational and statistical analyses of the association with 53 host-related factors. Fungal communities were characterized by a high prevalence of Saccharomyces, Candida, and Sporisorium. Ten factors were found to correlate significantly with the overall mycobiota variation. Most were diet related, including the consumption of chips, meat, sodas, sweetening, processed food, and alcohol, followed by age and marital status. Differences in α- and/or ß-diversity were also reported for other factors such as body mass index (BMI), job type, autoimmunological diseases, and probiotics. Differential abundance analysis revealed fungal species that exhibited different patterns of changes under specific conditions. The human gut mycobiota is dominated by yeast, including Saccharomyces, Malassezia, and Candida. Although intervolunteer variability was high, several fungal species persisted across most samples, which may be evidence that a core gut mycobiota exists. Moreover, we showed that host-related factors such as diet, age, and marital status influence the variability of gut mycobiota. To our knowledge, this is the first large and comprehensive study of the European cohort in terms of gut mycobiota associations with such an extensive and differentiated host-related set of factors. IMPORTANCE The human gut is inhabited by many organisms, including bacteria and fungi, that may affect human health. However, research on human gut mycobiome is still rare. Moreover, the large European-based cohort study is missing. Here, we analyzed the first large European cohort in terms of gut mycobiota associations with a differentiated host-related set of factors. Our results showed that chips, meat, sodas, sweetening, processed food, beer, alcohol consumption, age, and marital status were associated with the variability of gut mycobiota. Moreover, our analysis revealed changes in abundances at the fungal species level for many investigated factors. Our results can suggest potentially valuable paths for further, narrowly focused research on gut mycobiome and its impact on human health. In the coming era of gut microbiome-based precision medicine, further research into the relationship between different mycobial structures and host-related factors may result in new preventive approaches or therapeutic procedures.


Asunto(s)
Microbioma Gastrointestinal , Micobioma , Saccharomyces , Humanos , Estudios de Cohortes , Hongos/genética , Microbioma Gastrointestinal/genética , Heces/microbiología , Candida , Saccharomyces cerevisiae
9.
J Cell Mol Med ; 27(2): 299-303, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36606310

RESUMEN

Out of BCR-ABL negative myeloproliferative neoplasm (MPNPh- ) patients, 3%-14% display a concomitant monoclonal gammopathy of unknown significance (MGUS). In most cases, the diagnosis of plasma cell dyscrasia is either synchronous with that of MPNPh- or occurs later on. We present a 50-year-old patient with type 2 CALR Lys385Asnfs*47 mutation positive essential thrombocythemia (ET) who developed symptomatic multiple myeloma (MM) 13 years after the diagnosis of ET during PEG-INF2α treatment. The NGS study performed at the time of the MM diagnosis revealed the HRAS Val14Gly/c.41T〉G mutation and the wild type CALR, JAK2 and MPL gene sequence. In the presented case, the complete molecular remission of ET was achieved after 16 months of PEG-INF2α treatment. The origin of MM cells in MPNPh- patients remains unknown. Published data suggests that type 2 CALRins5 up-regulate the ATF6 chaperone targets in hematopoietic cells and activate the inositol-requiring enzyme 1α-X-box-binding protein 1 pathway of the unfolded protein response (UPR) system to drive malignancy. It cannot be excluded that endoplasmic reticulum stress induced by the increased ATF6 resulted in an abnormal redox homeostasis and proteostasis, which are factors linked to MM. The presented case history and the proposed mechanism of mutant CALR interaction with UPR and/or ATF6 should initiate the discussion about the possible impact of the mutant CALR protein on the function and genomic stability of different types of myeloid cells, including progenitor cells.


Asunto(s)
Mieloma Múltiple , Trastornos Mieloproliferativos , Trombocitemia Esencial , Humanos , Persona de Mediana Edad , Trombocitemia Esencial/genética , Trombocitemia Esencial/complicaciones , Trombocitemia Esencial/diagnóstico , Mieloma Múltiple/genética , Mieloma Múltiple/complicaciones , Trastornos Mieloproliferativos/genética , Mutación/genética , Inestabilidad Genómica , Janus Quinasa 2/metabolismo , Calreticulina/genética , Calreticulina/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética
10.
NMR Biomed ; 36(7): e4899, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36628624

RESUMEN

Liver magnetic resonance elastography (MRE) is a noninvasive stiffness measurement technique that captures the tissue displacement in the phase of the signal. To limit the scanning time to a single breath-hold, liver MRE usually involves advanced readout techniques such as simultaneous multislice (SMS) or multishot methods. Furthermore, all these readout techniques require additional in-plane acceleration using either parallel imaging capabilities, such as sensitivity encoding (SENSE), or k -space undersampling, such as compressed sensing (CS). However, these methods apply a single regularization function on the complex image. This study aims to design and evaluate methods that use separate regularization on the magnitude and phase of MRE to exploit their distinct spatiotemporal characteristics. Specifically, we introduce two compressed sensing methods. The first method, termed phase-regularized compressed sensing (PRCS), applies a two-dimensional total variation (TV) prior to the magnitude and two-dimensional wavelet regularization to the phase. The second method, termed displacement-regularized compressed sensing (DRCS), exploits the spatiotemporal redundancy using 3D total variation on the magnitude. Additionally, DRCS includes a displacement fitting function to apply wavelet regularization to the displacement phasor. Both DRCS and PRCS were evaluated with different levels of compression factors in three datasets: an in silico abdomen dataset, an in vitro tissue-mimicking phantom, and an in vivo liver dataset. The reconstructed images were compared with the full sampled reconstruction, zero-filling reconstruction, wavelet-regularized compressed sensing, and a low rank plus sparse reconstruction. The metrics used for quantitative evaluation were the structural similarity index (SSIM) of magnitude (M-SSIM), displacement (D-SSIM), and shear modulus (S-SSIM), and mean shear modulus. Results from highly undersampled in silico and in vitro datasets demonstrate that the DRCS method provides higher reconstruction quality than the conventional compressed sensing method for a wide range of stiffness values. Notably, DRCS provides 24% and 22% increase in D-SSIM compared with CS for the in silico and in vitro datasets, respectively. Comparison with liver stiffness measured from full sampled data and highly undersampled data (CR=4) demonstrates that the DRCS method provided the strongest correlation ( R 2 =0.95), second-lowest mean bias (-0.18 kPa, lowest for CS with -0.16 kPa), and lowest coefficient of variation (CV=3.6%). Our results demonstrate the potential of using DRCS to improve the reconstruction quality of accelerated MRE.


Asunto(s)
Compresión de Datos , Diagnóstico por Imagen de Elasticidad , Reproducibilidad de los Resultados , Compresión de Datos/métodos , Abdomen , Fantasmas de Imagen , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos
11.
Brain ; 146(6): 2298-2315, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36508327

RESUMEN

Huntingtin (HTT)-lowering therapies show great promise in treating Huntington's disease. We have developed a microRNA targeting human HTT that is delivered in an adeno-associated serotype 5 viral vector (AAV5-miHTT), and here use animal behaviour, MRI, non-invasive proton magnetic resonance spectroscopy and striatal RNA sequencing as outcome measures in preclinical mouse studies of AAV5-miHTT. The effects of AAV5-miHTT treatment were evaluated in homozygous Q175FDN mice, a mouse model of Huntington's disease with severe neuropathological and behavioural phenotypes. Homozygous mice were used instead of the more commonly used heterozygous strain, which exhibit milder phenotypes. Three-month-old homozygous Q175FDN mice, which had developed acute phenotypes by the time of treatment, were injected bilaterally into the striatum with either formulation buffer (phosphate-buffered saline + 5% sucrose), low dose (5.2 × 109 genome copies/mouse) or high dose (1.3 × 1011 genome copies/mouse) AAV5-miHTT. Wild-type mice injected with formulation buffer served as controls. Behavioural assessments of cognition, T1-weighted structural MRI and striatal proton magnetic resonance spectroscopy were performed 3 months after injection, and shortly afterwards the animals were sacrificed to collect brain tissue for protein and RNA analysis. Motor coordination was assessed at 1-month intervals beginning at 2 months of age until sacrifice. Dose-dependent changes in AAV5 vector DNA level, miHTT expression and mutant HTT were observed in striatum and cortex of AAV5-miHTT-treated Huntington's disease model mice. This pattern of microRNA expression and mutant HTT lowering rescued weight loss in homozygous Q175FDN mice but did not affect motor or cognitive phenotypes. MRI volumetric analysis detected atrophy in four brain regions in homozygous Q175FDN mice, and treatment with high dose AAV5-miHTT rescued this effect in the hippocampus. Like previous magnetic resonance spectroscopy studies in Huntington's disease patients, decreased total N-acetyl aspartate and increased myo-inositol levels were found in the striatum of homozygous Q175FDN mice. These neurochemical findings were partially reversed with AAV5-miHTT treatment. Striatal transcriptional analysis using RNA sequencing revealed mutant HTT-induced changes that were partially reversed by HTT lowering with AAV5-miHTT. Striatal proton magnetic resonance spectroscopy analysis suggests a restoration of neuronal function, and striatal RNA sequencing analysis shows a reversal of transcriptional dysregulation following AAV5-miHTT in a homozygous Huntington's disease mouse model with severe pathology. The results of this study support the use of magnetic resonance spectroscopy in HTT-lowering clinical trials and strengthen the therapeutic potential of AAV5-miHTT in reversing severe striatal dysfunction in Huntington's disease.


Asunto(s)
Enfermedad de Huntington , MicroARNs , Humanos , Animales , Ratones , Lactante , Enfermedad de Huntington/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Cuerpo Estriado/metabolismo , Encéfalo/patología , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Modelos Animales de Enfermedad
12.
Inorg Chem ; 62(9): 3761-3775, 2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36534941

RESUMEN

A series of {V12}-nuclearity polyoxovanadate cages covalently functionalized with one or sandwiched by two phthalocyaninato (Pc) lanthanide (Ln) moieties via V-O-Ln bonds were prepared and fully characterized for paramagnetic Ln = SmIII-ErIII and diamagnetic Ln = LuIII, including YIII. The LnPc-functionalized {V12O32} cages with fully oxidized vanadium centers in the ground state were isolated as (nBu4N)3[HV12O32Cl(LnPc)] and (nBu4N)2[HV12O32Cl(LnPc)2] compounds. As corroborated by a combined experimental (EPR, DC and AC SQUID, laser photolysis transient absorption spectroscopy, and electrochemistry) and computational (DFT, MD, and model Hamiltonian approach) methods, the compounds feature intra- and intermolecular electron transfer that is responsible for a partial reduction at V(3d) centers from VV to VIV in the solid state and at high sample concentrations. The effects are generally Ln dependent and are clearly demonstrated for the (nBu4N)3[HV12O32Cl(LnPc)] representative with Ln = LuIII or DyIII. Intramolecular charge transfer takes place for Ln = LuIII and occurs from a Pc ligand via the Ln center to the {V12O32} core of the same molecule, whereas for Ln = DyIII, only intermolecular charge transfer is allowed, which is realized from Pc in one molecule to the {V12O32} core of another molecule usually via the nBu4N+ countercation. For all Ln but DyIII, two of these phenomena may be present in different proportions. Besides, it is demonstrated that (nBu4N)3[HV12O32Cl(DyPc)] is a field-induced single molecule magnet with a maximal relaxation time of the order 10-3 s. The obtained results open up the way to further exploration and fine-tuning of these three modular molecular nanocomposites regarding tailoring and control of their Ln-dependent charge-separated states (induced by intramolecular transfer) and relaxation dynamics as well as of electron hopping between molecules. This should enable us to realize ultra-sensitive polyoxometalate powered quasi-superconductors, sensors, and data storage/processing materials for quantum technologies and neuromorphic computing.

13.
Magn Reson Med ; 89(5): 1809-1824, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36511247

RESUMEN

PURPOSE: We investigated the correlation, reproducibility, and effect of white matter fiber orientation for three myelin-sensitive MRI techniques: magnetization transfer ratio (MTR), inhomogeneous magnetization transfer ratio (ihMTR), and gradient and spin echo-derived myelin water fraction (MWF). METHODS: We measured the three metrics in 17 white and three deep grey matter regions in 17 healthy adults at 3 T. RESULTS: We found a strong correlation between ihMTR and MTR (r = 0.70, p < 0.001) and ihMTR and MWF (r = 0.79, p < 0.001), and a weaker correlation between MTR and MWF (r = 0.54, p < 0.001). The dynamic range in white matter was greatest for MWF (2.0%-27.5%), followed by MTR (14.4%-23.2%) and then ihMTR (1.2%-5.4%). The average scan-rescan coefficient of variation for white matter regions was 0.6% MTR, 0.3% ihMTR, and 0.7% MWF in metric units; however, when adjusted by the dynamic range, these became 6.3%, 6.1% and 2.8%, respectively. All three metrics varied with fiber direction: MWF and ihMTR were lower in white matter fibers perpendicular to B0 by 6% and 1%, respectively, compared with those parallel, whereas MTR was lower by 0.5% at about 40°, with the highest values at 90°. However, separating the apparent orientation dependence by white matter region revealed large dissimilarities in the trends, suggesting that real differences in myelination between regions are confounding the apparent orientation dependence measured using this method. CONCLUSION: The strong correlation between ihMTR and MWF suggests that these techniques are measuring the same myelination; however, the larger dynamic range of MWF may provide more power to detect small differences in myelin.


Asunto(s)
Vaina de Mielina , Sustancia Blanca , Humanos , Adulto , Reproducibilidad de los Resultados , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Agua , Biomarcadores
14.
Comput Struct Biotechnol J ; 20: 6443-6457, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467588

RESUMEN

MicroRNAs (miRNAs) are small non-coding RNAs that posttranscriptionally regulate the expression of most genes. They are involved in regulating many physiological processes, and aberrations in the levels of different miRNAs play an important role in the development of many diseases, including autoimmune diseases, neuropsychiatric diseases, and cancers. Although miRNAs are being intensively studied and levels of many miRNAs are either specifically increased or decreased in particular diseases, very little is known about the genetic variations of miRNA genes and their impact on the functioning of miRNA genes and human diseases. To shed more light on the potential effects of genetic variants in miRNA genes, we review here representative examples of SNPs, mutations linked to Mendelian diseases, and cancer somatic mutations located in miRNA genes and discuss their potential effects on the expression of miRNA genes, i.e., the structure and processing of miRNA precursors, the levels of generated miRNAs, miRNA target recognition/silencing, and impact on human diseases.

15.
Ann Hematol ; 101(12): 2665-2677, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36266510

RESUMEN

It has been postulated that the changes in the molecular characteristics of the malignant clone(s) and the abnormal activation of JAK-STAT signaling are responsible for myeloproliferative neoplasm progression to more advanced disease phases and the immune escape of the malignant clone. The continuous JAK-STAT pathway activation leads to enhanced activity of the promoter of CD274 coding programmed death-1 receptor ligand (PD-L1), increased PD-L1 level, and the immune escape of MPN cells. The aim of study was to evaluate the PDL1 mRNA and JAK2 mRNA level in molecularly defined essential thrombocythaemia (ET) patients (pts) during disease progression to post-ET- myelofibrosis (post-ET-MF). The study group consisted of 162 ET pts, including 30 pts diagnosed with post-ET-MF. The JAK2V617F, CALR, and MPL mutations were found in 59.3%, 19.1%, and 1.2% of pts, respectively. No copy-number alternations of the JAK2, PDL1, and PDCDL1G2 (PDL2) genes were found. The level of PD-L1 was significantly higher in the JAK2V617F than in the JAK2WT, CALR mutation-positive, and triple-negative pts. The PD-L1 mRNA level was weakly correlated with both the JAK2V617F variant allele frequency (VAF), and with the JAK2V617F allele mRNA level. The total JAK2 level in post-ET-MF pts was lower than in ET pts, despite the lack of differences in the JAK2V617F VAF. In addition, the PD-L1 level was lower in post-ET-MF. A detailed analysis has shown that the decrease in JAK2 and PDL1 mRNA levels depended on the bone marrow fibrosis grade. The PDL1 expression showed no differences in relation to the genotype of the JAK2 haplotypeGGCC_46/1, hemoglobin concentration, hematocrit value, leukocyte, and platelet counts. The observed drop of the total JAK2 and PDL1 levels during the ET progression to the post-ET-MF may reflect the changes in the JAK2V617F positive clone proliferative potential and the PD-L1 level-related immunosuppressive effect. The above-mentioned hypothesis is supported by The Cancer Genome Atlas (TCGA) data, confirming a strong positive association between CD274 (encoding PD-L1), CXCR3 (encoding CXCR3), and CSF1 (encoding M-CSF) expression levels, and recently published results documenting a drop in the CXCR3 level and circulating M-CSF in patients with post-ET-MF.


Asunto(s)
Trastornos Mieloproliferativos , Mielofibrosis Primaria , Trombocitemia Esencial , Humanos , Trombocitemia Esencial/genética , Trombocitemia Esencial/patología , Factor Estimulante de Colonias de Macrófagos/genética , Factor Estimulante de Colonias de Macrófagos/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Quinasas Janus/metabolismo , Factores de Transcripción STAT/genética , Factores de Transcripción STAT/metabolismo , Transducción de Señal , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/patología , Mutación , ARN Mensajero/genética , Calreticulina/genética , Calreticulina/metabolismo
16.
Sci Rep ; 12(1): 10924, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35764886

RESUMEN

Recent data indicate that MIR142 is the most frequently mutated miRNA gene and one of the most frequently mutated noncoding elements in all cancers, with mutations occurring predominantly in blood cancers, especially diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma. Functional analyses show that the MIR142 alterations have profound consequences for lympho- and myelopoiesis. Furthermore, one of the targets downregulated by miR-142-5p is CD274, which encodes PD-L1 that is elevated in many cancer types, including myeloproliferative neoplasms (MPNs). To extend knowledge about the occurrence of MIR142 mutations, we sequenced the gene in a large panel of MPNs [~ 700 samples, including polycythemia vera, essential thrombocythemia, primary myelofibrosis (PMF), and chronic myeloid leukemia], neoplasm types in which such mutations have never been tested, and in panels of acute myeloid leukemia (AML), and chronic lymphocytic leukemia (CLL). We identified 3 mutations (one in a PMF sample and two others in one CLL sample), indicating that MIR142 mutations are rare in MPNs. In summary, mutations in MIR142 are rare in MPNs; however, in specific subtypes, such as PMF, their frequency may be comparable to that observed in CLL or AML.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , Leucemia Mieloide Aguda , MicroARNs , Trastornos Mieloproliferativos , Humanos , MicroARNs/genética , Mutación , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología
17.
J Neurotrauma ; 39(23-24): 1708-1715, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35761793

RESUMEN

Over the past few decades, tremendous advances have been made in our understanding of the biological changes underpinning the devastating impairment of traumatic spinal cord injury (SCI). Much of this scientific research has focused on animal models of SCI, and comparatively little has been done in human SCI, largely because biospecimens from human SCI patients are not readily available. This paucity of scientific enquiry in human SCI represents an important void in the spectrum of translational research, as biological differences between animal models and the human condition need to be considered in the pre-clinical development of therapeutic approaches. The International Spinal Cord Injury Biobank (ISCIB) is a multi-user biorepository with the mission of accelerating therapeutic development in traumatic SCI through improved biological understanding of human injury, and the vision of serving as a global research resource where human SCI biospecimens are shared with researchers around the world. Aligned with internationally recognized best practices, ISCIB's formal governance structure and standard operating procedures have earned it official biobank certification through the Canadian Tissue Repository Network. Herein, we describe the translational research gap that ISCIB is helping to fill; its structure, governance and certification; how data and samples are accrued, processed and stored; and finally, the process through which samples and data are shared with global researchers. The purpose of this paper describing ISCIB is to serve as an introductory guidance document for the wider community of SCI researchers. By helping researchers understand the contents of ISCIB and the process of accessing biospecimens, we seek to further ISCIB's vision as being a resource for human and translational research in SCI, with the ultimate goal of finding disease-modifying therapies for this disabling condition.


Asunto(s)
Traumatismos de la Médula Espinal , Investigación Biomédica Traslacional , Animales , Humanos , Bancos de Muestras Biológicas , Canadá , Bancos de Tejidos , Médula Espinal
18.
BMC Cancer ; 22(1): 483, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35501736

RESUMEN

BACKGROUND: A critical challenge in current acute lymphoblastic leukemia (ALL) therapy is treatment intensification in order to reduce the relapse rate in the subset of patients at the highest risk of relapse. The year-long maintenance phase is essential in relapse prevention. The Thiopurine Enhanced ALL Maintenance (TEAM) trial investigates a novel strategy for ALL maintenance. METHODS: TEAM is a randomized phase 3 sub-protocol to the ALLTogether1 trial, which includes patients 0-45 years of age with newly diagnosed B-cell precursor or T-cell ALL, and stratified to the intermediate risk-high (IR-high) group, in 13 European countries. In the TEAM trial, the traditional methotrexate (MTX)/6-mercaptopurine (6MP) maintenance backbone (control arm) is supplemented with low dose (2.5-12.5 mg/m2/day) oral 6-thioguanine (6TG) (experimental arm), while the starting dose of 6MP is reduced from 75 to 50 mg/m2/day. A total of 778 patients will be included in TEAM during ~ 5 years. The study will close when the last included patient has been followed for 5 years from the end of induction therapy. The primary objective of the study is to significantly improve the disease-free survival (DFS) of IR-high ALL patients by adding 6TG to 6MP/MTX-based maintenance therapy. TEAM has 80% power to detect a 7% increase in 5-year DFS through a 50% reduction in relapse rate. DFS will be evaluated by intention-to-treat analysis. In addition to reducing relapse, TEAM may also reduce hepatotoxicity and hypoglycemia caused by high levels of methylated 6MP metabolites. Methotrexate/6MP metabolites will be monitored and low levels will be reported back to clinicians to identify potentially non-adherent patients. DISCUSSION: TEAM provides a novel strategy for maintenance therapy in ALL with the potential of improving DFS through reducing relapse rate. Potential risk factors that have been considered include hepatic sinusoidal obstruction syndrome/nodular regenerative hyperplasia, second cancer, infection, and osteonecrosis. Metabolite monitoring can potentially increase treatment adherence in both treatment arms. TRIAL REGISTRATION: EudraCT, 2018-001795-38. Registered 2020-05-15, Clinicaltrials.gov , NCT04307576 . Registered 2020-03-13, https://clinicaltrials.gov/ct2/show/NCT04307576.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Adolescente , Adulto , Niño , Preescolar , Supervivencia sin Enfermedad , Humanos , Lactante , Recién Nacido , Mercaptopurina , Metotrexato , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Factores de Riesgo , Linfocitos T , Tioguanina/uso terapéutico , Adulto Joven
19.
IEEE Trans Med Imaging ; 41(11): 3039-3052, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35617177

RESUMEN

We introduce two model-based iterative methods to obtain shear modulus images of tissue using magnetic resonance elastography. The first method jointly finds the displacement field that best fits tissue displacement data and the corresponding shear modulus. The displacement satisfies a viscoelastic wave equation constraint, discretized using the finite element method. Sparsifying regularization terms in both shear modulus and displacement are used in the cost function minimized for the best fit. The second method extends the first method for multifrequency tissue displacement data. The formulated problems are bi-convex. Their solution can be obtained iteratively by using the alternating direction method of multipliers. Sparsifying regularizations and the wave equation constraint filter out sensor noise and compressional waves. Our methods do not require bandpass filtering as a preprocessing step and converge fast irrespective of the initialization. We evaluate our new methods in multiple in silico and phantom experiments, with comparisons with existing methods, and we show improvements in contrast to noise and signal-to-noise ratios. Results from an in vivo liver imaging study show elastograms with mean elasticity comparable to other values reported in the literature.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Elasticidad , Fantasmas de Imagen , Diagnóstico por Imagen de Elasticidad/métodos , Algoritmos , Relación Señal-Ruido
20.
J Neurotrauma ; 39(23-24): 1603-1635, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35538847

RESUMEN

Intraparenchymal hemorrhage (IPH) after a traumatic injury has been associated with poor neurological outcomes. Although IPH may result from the initial mechanical trauma, the blood and its breakdown products have potentially deleterious effects. Further, the degree of IPH has been correlated with injury severity and the extent of subsequent recovery. Therefore, accurate evaluation and quantification of IPH following traumatic spinal cord injury (SCI) is important to define treatments' effects on IPH progression and secondary neuronal injury. Imaging modalities, such as magnetic resonance imaging (MRI) and ultrasound (US), have been explored by researchers for the detection and quantification of IPH following SCI. Both quantitative and semiquantitative MRI and US measurements have been applied to objectively assess IPH following SCI, but the optimal methods for doing so are not well established. Studies in animal SCI models (rodent and porcine) have explored US and histological techniques in evaluating SCI and have demonstrated the potential to detect and quantify IPH. Newer techniques using machine learning algorithms (such as convolutional neural networks [CNN]) have also been studied to calculate IPH volume and have yielded promising results. Despite long-standing recognition of the potential pathological significance of IPH within the spinal cord, quantifying IPH with MRI or US is a relatively new area of research. Further studies are warranted to investigate their potential use. Here, we review the different and emerging quantitative MRI, US, and histological approaches used to detect and quantify IPH following SCI.


Asunto(s)
Traumatismos de la Médula Espinal , Animales , Porcinos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Hemorragia/patología , Imagen por Resonancia Magnética/métodos
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