RESUMEN
Ribosomal protein (RP) expression in higher eukaryotes is regulated translationally through the 5'TOP sequence. This mechanism evolved to more rapidly produce RPs on demand in different tissues. Here we show that 40S ribosomes, in a complex with the mRNA binding protein LARP1, selectively stabilize 5'TOP mRNAs, with disruption of this complex leading to induction of the impaired ribosome biogenesis checkpoint (IRBC) and p53 stabilization. The importance of this mechanism is underscored in 5q− syndrome, a macrocytic anemia caused by a large monoallelic deletion, which we found to also encompass the LARP1 gene. Critically, depletion of LARP1 alone in human adult CD34+ bone marrow precursor cells leads to a reduction in 5'TOP mRNAs and the induction of p53. These studies identify a 40S ribosome function independent of those in translation that, with LARP1, mediates the autogenous control of 5'TOP mRNA stability, whose disruption is implicated in the pathophysiology of 5q− syndrome.
Asunto(s)
Autoantígenos/metabolismo , Biosíntesis de Proteínas , Secuencia de Oligopirimidina en la Región 5' Terminal del ARN , Estabilidad del ARN , ARN Mensajero/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo , Anemia Macrocítica/genética , Anemia Macrocítica/metabolismo , Autoantígenos/genética , Células de la Médula Ósea/metabolismo , Deleción Cromosómica , Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 5/metabolismo , Células HCT116 , Humanos , Complejos Multiproteicos , Unión Proteica , Interferencia de ARN , ARN Mensajero/genética , Ribonucleoproteínas/genética , Proteínas Ribosómicas/genética , Ribosomas/genética , Factores de Tiempo , Transfección , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Antígeno SS-BRESUMEN
HMGA1 is a structural epigenetic chromatin factor that has been associated with tumor progression and drug resistance. Here, we reported the prognostic/predictive value of HMGA1 for trabectedin in advanced soft-tissue sarcoma (STS) and the effect of inhibiting HMGA1 or the mTOR downstream pathway in trabectedin activity. The prognostic/predictive value of HMGA1 expression was assessed in a cohort of 301 STS patients at mRNA (n = 133) and protein level (n = 272), by HTG EdgeSeq transcriptomics and immunohistochemistry, respectively. The effect of HMGA1 silencing on trabectedin activity and gene expression profiling was measured in leiomyosarcoma cells. The effect of combining mTOR inhibitors with trabectedin was assessed on cell viability in vitro studies, whereas in vivo studies tested the activity of this combination. HMGA1 mRNA and protein expression were significantly associated with worse progression-free survival of trabectedin and worse overall survival in STS. HMGA1 silencing sensitized leiomyosarcoma cells for trabectedin treatment, reducing the spheroid area and increasing cell death. The downregulation of HGMA1 significantly decreased the enrichment of some specific gene sets, including the PI3K/AKT/mTOR pathway. The inhibition of mTOR, sensitized leiomyosarcoma cultures for trabectedin treatment, increasing cell death. In in vivo studies, the combination of rapamycin with trabectedin downregulated HMGA1 expression and stabilized tumor growth of 3-methylcholantrene-induced sarcoma-like models. HMGA1 is an adverse prognostic factor for trabectedin treatment in advanced STS. HMGA1 silencing increases trabectedin efficacy, in part by modulating the mTOR signaling pathway. Trabectedin plus mTOR inhibitors are active in preclinical models of sarcoma, downregulating HMGA1 expression levels and stabilizing tumor growth.
Asunto(s)
Proteína HMGA1a , Sarcoma , Trabectedina , Trabectedina/farmacología , Humanos , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Sarcoma/genética , Sarcoma/metabolismo , Proteína HMGA1a/metabolismo , Proteína HMGA1a/genética , Animales , Línea Celular Tumoral , Ratones , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Pronóstico , Femenino , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/patología , Leiomiosarcoma/genética , Leiomiosarcoma/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Gastrointestinal stromal tumours (GISTs) are prevalent mesenchymal tumours of the gastrointestinal tract, commonly exhibiting structural variations in KIT and PDGFRA genes. While the mutational profiling of somatic tumours is well described, the genes behind the susceptibility to develop GIST are not yet fully discovered. This study explores the genomic landscape of two primary GIST cases, aiming to identify shared germline pathogenic variants and shed light on potential key players in tumourigenesis. METHODS: Two patients with distinct genotypically and phenotypically GISTs underwent germline whole genome sequencing. CNV and single nucleotide variant (SNV) analyses were performed. RESULTS: Both patients harbouring low-risk GISTs with different mutations (PDGFRA and KIT) shared homozygous germline pathogenic deletions in both CFHR1 and CFHR3 genes. CNV analysis revealed additional shared pathogenic deletions in other genes such as SLC25A24. No particular pathogenic SNV shared by both patients was detected. CONCLUSION: Our study provides new insights into germline variants that can be associated with the development of GISTs, namely, CFHR1 and CFHR3 deep deletions. Further functional validation is warranted to elucidate the precise contributions of identified germline mutations in GIST development.
RESUMEN
Catalase is a major antioxidant enzyme located in plant peroxisomes that catalyzes the decomposition of H2O2. Based on our previous transcriptomic (RNA-Seq) and proteomic (iTRAQ) data at different stages of pepper (Capsicum annuum L.) fruit ripening and after exposure to nitric oxide (NO) enriched atmosphere, a broad analysis has allowed us to characterize the functioning of this enzyme. Three genes were identified, and their expression was differentially modulated during ripening and by NO gas treatment. A dissimilar behavior was observed in the protein expression of the encoded protein catalases (CaCat1-CaCat3). Total catalase activity was down-regulated by 50% in ripe (red) fruits concerning immature green fruits. This was corroborated by non-denaturing polyacrylamide gel electrophoresis, where only a single catalase isozyme was identified. In vitro analyses of the recombinant CaCat3 protein exposed to peroxynitrite (ONOO-) confirmed, by immunoblot assay, that catalase underwent a nitration process. Mass spectrometric analysis identified that Tyr348 and Tyr360 were nitrated by ONOO-, occurring near the active center of catalase. The data indicate the complex regulation at gene and protein levels of catalase during the ripening of pepper fruits, with activity significantly down-regulated in ripe fruits. Nitration seems to play a key role in this down-regulation, favoring an increase in H2O2 content during ripening. This pattern can be reversed by the exogenous NO application. While plant catalases are generally reported to be tetrameric, the analysis of the protein structure supports that pepper catalase has a favored quaternary homodimer nature. Taken together, data show that pepper catalase is down-regulated during fruit ripening, becoming a target of tyrosine nitration, which provokes its inhibition.
Asunto(s)
Capsicum , Catalasa , Frutas , Óxido Nítrico , Proteínas de Plantas , Capsicum/genética , Capsicum/crecimiento & desarrollo , Capsicum/enzimología , Capsicum/metabolismo , Catalasa/metabolismo , Catalasa/genética , Frutas/crecimiento & desarrollo , Frutas/genética , Frutas/metabolismo , Frutas/enzimología , Frutas/efectos de los fármacos , Óxido Nítrico/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Ácido Peroxinitroso/metabolismoRESUMEN
During meiotic prophase I, homologous chromosomes pair, synapse and recombine in a tightly regulated process that ensures the generation of genetically variable haploid gametes. Although the mechanisms underlying meiotic cell division have been well studied in model species, our understanding of the dynamics of meiotic prophase I in non-traditional model mammals remains in its infancy. Here, we reveal key meiotic features in previously uncharacterised marsupial species (the tammar wallaby and the fat-tailed dunnart), plus the fat-tailed mouse opossum, with a focus on sex chromosome pairing strategies, recombination and meiotic telomere homeostasis. We uncovered differences between phylogroups with important functional and evolutionary implications. First, sex chromosomes, which lack a pseudo-autosomal region in marsupials, had species specific pairing and silencing strategies, with implications for sex chromosome evolution. Second, we detected two waves of γH2AX accumulation during prophase I. The first wave was accompanied by low γH2AX levels on autosomes, which correlated with the low recombination rates that distinguish marsupials from eutherian mammals. In the second wave, γH2AX was restricted to sex chromosomes in all three species, which correlated with transcription from the X in tammar wallaby. This suggests non-canonical functions of γH2AX on meiotic sex chromosomes. Finally, we uncover evidence for telomere elongation in primary spermatocytes of the fat-tailed dunnart, a unique strategy within mammals. Our results provide new insights into meiotic progression and telomere homeostasis in marsupials, highlighting the importance of capturing the diversity of meiotic strategies within mammals.
Asunto(s)
Emparejamiento Cromosómico/fisiología , Cromosomas Sexuales/fisiología , Telómero/fisiología , Animales , Macropodidae/genética , Marsupiales/genética , Meiosis/genética , Meiosis/fisiología , Profase Meiótica I/fisiología , Zarigüeyas/genética , Cromosomas Sexuales/genética , Telómero/genética , Cromosoma X/genética , Cromosoma Y/genéticaRESUMEN
BACKGROUND: The Konectom™ smartphone-based cognitive processing speed (CPS) test is designed to assess processing speed and account for impact of visuomotor function on performance. OBJECTIVE: Evaluate reliability and validity of Konectom CPS Test, performed in clinic and remotely. METHODS: Data were collected from people with multiple sclerosis (PwMS) aged 18-64 years and healthy control participants (HC) matched for age, sex, and education. Remote test-retest reliability (intraclass correlation coefficients, ICC); correlation with established clinical measures (Spearman correlation coefficients); group analyses between cognitively impaired/unimpaired PwMS; and influence of age, sex, education, and upper limb motor function on CPS Test measures were assessed. RESULTS: Eighty PwMS and 66 HC participated. CPS Test measures from remote tests had good test-retest reliability (ICC of 0.67-0.87) and correlated with symbol digit modalities test (highest |ρ| = 0.80, p < 0.0001). Remote measures were stable (change from baseline < 5%) and correlated with MS disability (highest |ρ| = 0.39, p = 0.0004) measured by Expanded Disability Status Scale. CPS Test measures displayed sensitivity to cognitive impairment (highest d = 1.47). Demographics and motor function had the lowest impact on CPS Test substitution time, a measure accounting for visuomotor function. CONCLUSION: Konectom CPS Test measures provide valid, reliable remote measurements of cognitive processing speed in PwMS.
Asunto(s)
Disfunción Cognitiva , Esclerosis Múltiple , Pruebas Neuropsicológicas , Humanos , Adulto , Masculino , Femenino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico , Adulto Joven , Pruebas Neuropsicológicas/normas , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Adolescente , Teléfono Inteligente , Desempeño Psicomotor/fisiología , Evaluación de Resultado en la Atención de Salud , Cognición/fisiología , Velocidad de ProcesamientoRESUMEN
PURPOSE: To investigate the clinical manifestations, management and outcomes of Leishmania lesions in the ear-nose-throat (ENT) region, and its relationship with tumor necrosis factor (TNF)-α blocking drugs. METHODS: Single-center retrospective observational study. Patients diagnosed with cutaneous and mucosal leishmaniasis in the otorhinolaryngologic area at a tertiary referral center over a period of 8 years. RESULTS: Three cases of Leishmania lesions in the ear and two in the nose were encountered at our institution. All patients were under treatment with TNF-α blocking drugs. Diagnosis was challenging, and it was important to have a clinical suspicion in order to use accurate detection techniques. All patients received systemic treatment and achieved a complete resolution of the lesions. CONCLUSIONS: With the increasing use of biologic treatments like TNF-α blockers, this type of infection will be increasingly frequent in endemic areas and also worldwide. It is important to include leishmaniasis in the differential diagnosis of inflammatory/infectious lesions in the ENT region.
Asunto(s)
Leishmaniasis Cutánea , Leishmaniasis , Otolaringología , Humanos , Factor de Necrosis Tumoral alfa , Leishmaniasis/diagnóstico , Leishmaniasis/tratamiento farmacológico , Piel , Estudios Retrospectivos , Leishmaniasis Cutánea/terapiaRESUMEN
BACKGROUND: Approximately 15% of adult GIST patients harbor tumors that are wild-type for KIT and PDGFRα genes (KP-wtGIST). These tumors usually have SDH deficiencies, exhibit a more indolent behavior and are resistant to imatinib. Underlying oncogenic mechanisms in KP-wtGIST include overexpression of HIF1α high IGFR signaling through the MAPK pathway or BRAF activating mutation, among others. As regorafenib inhibits these signaling pathways, it was hypothesized that it could be more active as upfront therapy in advanced KP-wtGIST. METHODS: Adult patients with advanced KP-wtGIST after central confirmation by NGS, naïve of systemic treatment for advanced disease, were included in this international phase II trial. Eligible patients received regorafenib 160 mg per day for 21 days every 28 days. The primary endpoint was disease control rate (DCR), according to RECIST 1.1 at 12 weeks by central radiological assessment. RESULTS: From May 2016 to October 2020, 30 patients were identified as KP-wtGIST by Sanger sequencing and 16 were confirmed by central molecular screening with NGS. Finally, 15 were enrolled and received regorafenib. The study was prematurely closed due to the low accrual worsened by COVID outbreak. The DCR at 12 weeks was 86.7% by central assessment. A subset of 60% experienced some tumor shrinkage, with partial responses and stabilization observed in 13% and 87% respectively, by central assessment. SDH-deficient GIST showed better clinical outcome than other KP-wtGIST. CONCLUSIONS: Regorafenib activity in KP-wtGIST compares favorably with other tyrosine kinase inhibitors, especially in the SDH-deficient GIST subset and it should be taken into consideration as upfront therapy of advanced KP-wtGIST. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02638766.
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Antineoplásicos , Tumores del Estroma Gastrointestinal , Sarcoma , Adulto , Humanos , Antineoplásicos/uso terapéutico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-kit/genética , Sarcoma/tratamiento farmacológicoRESUMEN
S-Nitrosoglutathione plays a central role in nitric oxide (NO) homeostasis, and S-nitrosoglutathione reductase (GSNOR) regulates the cellular levels of S-nitrosoglutathione across kingdoms. Here, we investigated the role of endogenous NO in shaping shoot architecture and controlling fruit set and growth in tomato (Solanum lycopersicum). SlGSNOR silencing promoted shoot side branching and led to reduced fruit size, negatively impacting fruit yield. Greatly intensified in slgsnor knockout plants, these phenotypical changes were virtually unaffected by SlGSNOR overexpression. Silencing or knocking out of SlGSNOR intensified protein tyrosine nitration and S-nitrosation and led to aberrant auxin production and signaling in leaf primordia and fruit-setting ovaries, besides restricting the shoot basipetal polar auxin transport stream. SlGSNOR deficiency triggered extensive transcriptional reprogramming at early fruit development, reducing pericarp cell proliferation due to restrictions on auxin, gibberellin, and cytokinin production and signaling. Abnormal chloroplast development and carbon metabolism were also detected in early-developing NO-overaccumulating fruits, possibly limiting energy supply and building blocks for fruit growth. These findings provide new insights into the mechanisms by which endogenous NO fine-tunes the delicate hormonal network controlling shoot architecture, fruit set, and post-anthesis fruit development, emphasizing the relevance of NO-auxin interaction for plant development and productivity.
Asunto(s)
Reguladores del Crecimiento de las Plantas , Solanum lycopersicum , Reguladores del Crecimiento de las Plantas/metabolismo , Oxidorreductasas/metabolismo , Solanum lycopersicum/genética , Frutas/metabolismo , S-Nitrosoglutatión/metabolismo , Ácidos Indolacéticos/metabolismo , Homeostasis , Óxido Nítrico/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
BACKGROUND AND PURPOSE: A diagnostic score was developed to discriminate anti-myelin-associated-glycoprotein (MAG) neuropathy from chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and applied it to patients with atypical anti-MAG neuropathy. METHODS: The clinical and electrophysiological features of patients with a diagnosis of typical anti-MAG neuropathy were compared to those of patients with a diagnosis of CIDP. The association of each feature with the diagnosis was assessed in the two groups. Features showing a significant association with the diagnosis were included in a multivariable logistic regression model and adjusted odds ratios were estimated for each feature. A score ranging from 1 to 3 was applied to each feature based on the magnitude of the estimated odds ratios. The score was then applied to patients with a clinical diagnosis of CIDP who also had high anti-MAG antibody titers (CIDP-MAG). RESULTS: Thirty-one anti-MAG neuropathy patients, 45 typical CIDP patients and 16 CIDP-MAG patients were included. Scores in anti-MAG antibody patients ranged from 1 to 5 and in CIDP patients from -7 to -1. Using the score, 4/16 CIDP-MAG patients were diagnosed to have anti-MAG neuropathy and 12/16 patients to have CIDP. Response to intravenous immunoglobulin in the CIDP-MAG patients classified as CIDP was similar to that of definite CIDP patients and higher than that of anti-MAG neuropathy patients. CONCLUSIONS: Our score allowed an accurate discrimination to be made, amongst patients with anti-MAG antibodies, of those affected by CIDP and the patients with anti-MAG neuropathy. This score may help proper treatment to be chosen for patients with anti-MAG antibodies with a CIDP-like presentation.
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Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Polirradiculoneuropatía , Humanos , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/terapia , Inmunoglobulina M , Inmunoglobulinas Intravenosas/uso terapéutico , Autoanticuerpos , Glicoproteína Asociada a Mielina , Polirradiculoneuropatía/tratamiento farmacológicoRESUMEN
We present here the first detailed description of the seasonal patterns in bacterial community composition (BCC) in shelf waters off the Ría de Vigo (Spain), based on monthly samplings during 2 years. Moreover, we studied the relationship between bacterial and small-sized eukaryotic community composition to identify potential biotic interactions among components of these two communities. Bacterial operational taxonomic unit (OTU) richness and diversity systematically peaked in autumn-winter, likely related to low resource availability during this period. BCC showed seasonal and vertical patterns, with Rhodobacteraceae and Flavobacteriaceae families dominating in surface waters, and SAR11 clade dominating at the base of the photic zone (30 m depth). BCC variability was significantly explained by environmental variables (e.g., temperature of water, solar radiation, or dissolved organic matter). Interestingly, a strong and significant correlation was found between BCC and small-sized eukaryotic community composition (ECC), which suggests that biotic interactions may play a major role as structuring factors of the microbial plankton in this productive area. In addition, co-occurrence network analyses revealed strong and significant, mostly positive, associations between bacteria and small-sized phytoplankton. Positive associations likely result from mutualistic relationships (e.g., between Dinophyceae and Rhodobacteraceae), while some negative correlations suggest antagonistic interactions (e.g., between Pseudo-nitzchia sp. and SAR11). These results support the key role of biotic interactions as structuring factors of the small-sized eukaryotic community, mostly driven by positive associations between small-sized phytoplankton and bacteria.
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Fitoplancton , Plancton , Humanos , Bacterias , Estaciones del Año , EucariontesRESUMEN
Sex chromosomes of eutherian mammals are highly different in size and gene content, and share only a small region of homology (pseudoautosomal region, PAR). They are thought to have evolved through an addition-attrition cycle involving the addition of autosomal segments to sex chromosomes and their subsequent differentiation. The events that drive this process are difficult to investigate because sex chromosomes in almost all mammals are at a very advanced stage of differentiation. Here, we have taken advantage of a recent translocation of an autosome to both sex chromosomes in the African pygmy mouse Mus minutoides, which has restored a large segment of homology (neo-PAR). By studying meiotic sex chromosome behavior and identifying fully sex-linked genetic markers in the neo-PAR, we demonstrate that this region shows unequivocal signs of early sex-differentiation. First, synapsis and resolution of DNA damage intermediates are delayed in the neo-PAR during meiosis. Second, recombination is suppressed or largely reduced in a large portion of the neo-PAR. However, the inactivation process that characterizes sex chromosomes during meiosis does not extend to this region. Finally, the sex chromosomes show a dual mechanism of association at metaphase-I that involves the formation of a chiasma in the neo-PAR and the preservation of an ancestral achiasmate mode of association in the non-homologous segments. We show that the study of meiosis is crucial to apprehend the onset of sex chromosome differentiation, as it introduces structural and functional constrains to sex chromosome evolution. Synapsis and DNA repair dynamics are the first processes affected in the incipient differentiation of X and Y chromosomes, and they may be involved in accelerating their evolution. This provides one of the very first reports of early steps in neo-sex chromosome differentiation in mammals, and for the first time a cellular framework for the addition-attrition model of sex chromosome evolution.
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Meiosis/genética , Ratones/genética , Diferenciación Sexual/genética , Animales , Euterios/genética , Femenino , Masculino , Mamíferos/genética , Regiones Pseudoautosómicas , Cromosomas Sexuales/genética , Translocación Genética/genética , Cromosoma X/genética , Cromosoma Y/genéticaRESUMEN
The uncoupling protein UCP2 is a mitochondrial carrier for which transport activity remains controversial. The physiological contexts in which UCP2 is expressed have led to the assumption that, like UCP1, it uncouples oxidative phosphorylation and thereby reduces the generation of reactive oxygen species. Other reports have involved UCP2 in the Warburg effect, and results showing that UCP2 catalyzes the export of matrix C4 metabolites to facilitate glutamine utilization suggest that the carrier could be involved in the metabolic adaptations required for cell proliferation. We have examined the role of UCP2 in the energy metabolism of the lung adenocarcinoma cell line A549 and show that UCP2 silencing decreased the basal rate of respiration, although this inhibition was not compensated by an increase in glycolysis. Silencing did not lead to either changes in proton leakage, as determined by the rate of respiration in the absence of ATP synthesis, or changes in the rate of formation of reactive oxygen species. The decrease in energy metabolism did not alter the cellular energy charge. The decreased cell proliferation observed in UCP2-silenced cells would explain the reduced cellular ATP demand. We conclude that UCP2 does not operate as an uncoupling protein, whereas our results are consistent with its activity as a C4-metabolite carrier involved in the metabolic adaptations of proliferating cells.
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Metabolismo Energético , Canales Iónicos , Neoplasias Pulmonares , Proteína Desacopladora 2 , Humanos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Adenosina Trifosfato/metabolismo , Línea Celular , Canales Iónicos/genética , Canales Iónicos/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Proteínas Desacopladoras Mitocondriales/metabolismo , Neoplasias , Especies Reactivas de Oxígeno/metabolismo , Proteína Desacopladora 2/genética , Proteína Desacopladora 2/metabolismoRESUMEN
Sex determination in mammals is usually provided by a pair of chromosomes, XX in females and XY in males. Mole voles of the genus Ellobius are exceptions to this rule. In Ellobius tancrei, both males and females have a pair of XX chromosomes that are indistinguishable from each other in somatic cells. Nevertheless, several studies on Ellobius have reported that the two X chromosomes may have a differential organization and behavior during male meiosis. It has not yet been demonstrated if these differences also appear in female meiosis. To test this hypothesis, we have performed a comparative study of chromosome synapsis, recombination, and histone modifications during male and female meiosis in E. tancrei. We observed that synapsis between the two X chromosomes is limited to the short distal (telomeric) regions of the chromosomes in males, leaving the central region completely unsynapsed. This uneven behavior of sex chromosomes during male meiosis is accompanied by structural modifications of one of the X chromosomes, whose axial element tends to appear fragmented, accumulates the heterochromatin mark H3K9me3, and is associated with a specific nuclear body that accumulates epigenetic marks and proteins such as SUMO-1 and centromeric proteins but excludes others such as H3K4me, ubiH2A, and γH2AX. Unexpectedly, sex chromosome synapsis is delayed in female meiosis, leaving the central region unsynapsed during early pachytene. This region accumulates γH2AX up to the stage in which synapsis is completed. However, there are no structural or epigenetic differences similar to those found in males in either of the two X chromosomes. Finally, we observed that recombination in the sex chromosomes is restricted in both sexes. In males, crossover-associated MLH1 foci are located exclusively in the distal regions, indicating incipient differentiation of one of the sex chromosomes into a neo-Y. Notably, in female meiosis, the central region of the X chromosome is also devoid of MLH1 foci, revealing a lack of recombination, possibly due to insufficient homology. Overall, these results reveal new clues about the origin and evolution of sex chromosomes.
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Arvicolinae , Caracteres Sexuales , Animales , Arvicolinae/genética , Femenino , Masculino , Meiosis , Cromosomas Sexuales/genética , Cromosoma X/genética , Cromosoma Y/genéticaRESUMEN
The thiol group of cysteine (Cys) residues, often present in the active center of the protein, is of particular importance to protein function, which is significantly determined by the redox state of a protein's environment. Our knowledge of different thiol-based oxidative posttranslational modifications (oxiPTMs), which compete for specific protein thiol groups, has increased over the last 10 years. The principal oxiPTMs include S-sulfenylation, S-glutathionylation, S-nitrosation, persulfidation, S-cyanylation and S-acylation. The role of each oxiPTM depends on the redox cellular state, which in turn depends on cellular homeostasis under either optimal or stressful conditions. Under such conditions, the metabolism of molecules such as glutathione, NADPH (reduced nicotinamide adenine dinucleotide phosphate), nitric oxide, hydrogen sulfide and hydrogen peroxide can be altered, exacerbated and, consequently, outside the cell's control. This review provides a broad overview of these oxiPTMs under physiological and unfavorable conditions, which can regulate the function of target proteins.
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Proteínas de Plantas , Compuestos de Sulfhidrilo , Glutatión/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Proteínas de Plantas/metabolismo , Procesamiento Proteico-Postraduccional , Compuestos de Sulfhidrilo/metabolismoRESUMEN
Fruit ripening is a physiological process that involves a complex network of signaling molecules that act as switches to activate or deactivate certain metabolic pathways at different levels, not only by regulating gene and protein expression but also through post-translational modifications of the involved proteins. Ethylene is the distinctive molecule that regulates the ripening of fruits, which can be classified as climacteric or non-climacteric according to whether or not, respectively, they are dependent on this phytohormone. However, in recent years it has been found that other molecules with signaling potential also exert regulatory roles, not only individually but also as a result of interactions among them. These observations imply the existence of mutual and hierarchical regulations that sometimes make it difficult to identify the initial triggering event. Among these 'new' molecules, hydrogen peroxide, nitric oxide, and melatonin have been highlighted as prominent. This review provides a comprehensive outline of the relevance of these molecules in the fruit ripening process and the complex network of the known interactions among them.
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Melatonina , Óxido Nítrico , Etilenos/metabolismo , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Peróxido de Hidrógeno/metabolismo , Melatonina/metabolismo , Óxido Nítrico/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Estudios Prospectivos , Especies Reactivas de Oxígeno/metabolismoRESUMEN
INTRODUCTION: Serum gamma-glutamyl transferase activity (GGT) seems to predict cardiovascular events in different populations. However, no data exist on patients with congenital heart disease (CHD). METHODS: Observational, analytic, prospective cohort study design involving CHD patients and a control population to determine the effect of GGT levels on survival. RESULTS: A total of 589 CHD patients (58% males, 29 ± 14 years old) and 2745 matched control patients were followed up. A total of 69 (12%) CHD patients had a major acute cardiovascular event (MACE) during the follow-up time (6.1 [0.7-10.4] years). Patients with CHD and a GGT >60 U/L were significantly older, more hypertensive and dyslipidemic, had a worse NYHA functional class and a greater anatomical complexity than CHD patients with a GGT ≤60 U/L. The binary logistic regression analysis showed that age, a great CHD anatomical complexity, and having atrial fibrillation/flutter were the predictive factors of higher GGT levels (>60 U/L). The Kaplan-Meier analysis showed that patients with CHD and a GGT concentration above 60 UL showed the lowest probability of survival compared to that of CHD with GGT ≤60 U/L and controls irrespective of their GGT concentrations (p < .001). Similarly, the multivariable Cox regression analysis found an independent association between higher GGT levels (>60 U/L) and a worse prognosis (HR 2.44 [1.34-4.44], p = .003) among patients with CHD. CONCLUSION: Patients with CHD showed significant higher GGT levels than patients in the control group having those with higher GGT concentrations (>60 U/L) the worst survival.
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Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Cardiopatías Congénitas/sangre , Cardiopatías Congénitas/complicaciones , gamma-Glutamiltransferasa/sangre , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Adulto JovenRESUMEN
PURPOSE OF REVIEW: To review the evidence about video game-based therapeutic intervention for people diagnosed with depressive disorders. RECENT FINDINGS: Psychotherapy has been proved to reduce depressive symptoms and is a key element in the treatment of depressive disorders. However, geographical, economical and stigmatized concerns are barriers to access to psychotherapy. New technologies and videos games can overcome some of these barriers by providing teleconferencing evidence-based therapy as time as they may offer an interactive entertainment. Overall, video game-based interventions were useful and effective in reducing symptoms of depressive disorders. Seven of the studies were published in the last 5 years, which reflects the increased research interest in video game-based interventions for depression. Overall, when adherence was reported, rates of acceptability and feasibility were high.
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Trastorno Depresivo , Juegos de Video , Depresión/terapia , Trastorno Depresivo/terapia , Humanos , PsicoterapiaRESUMEN
Dental caries is the major biofilm-mediated oral disease in the world. The main treatment to restore caries lesions consists of the use of adhesive resin composites due to their good properties. However, the progressive degradation of the adhesive in the medium term makes possible the proliferation of cariogenic bacteria allowing secondary caries to emerge. In this study, a dental adhesive incorporating a drug delivery system based on L-arginine-containing mesoporous silica nanoparticles (MSNs) was used to release this essential amino acid as a source of basicity to neutralize the harmful acidic conditions that mediate the development of dental secondary caries. The in vitro and bacterial culture experiments proved that L-arginine was released in a sustained way from MSNs and diffused out from the dental adhesive, effectively contributing to the reduction of the bacterial strains Streptococcus mutans and Lactobacillus casei. Furthermore, the mechanical and bonding properties of the dental adhesive did not change significantly after the incorporation of L-arginine-containing MSNs. These results are yielding glimmers of promise for the cost-effective prevention of secondary caries.
Asunto(s)
Caries Dental , Nanopartículas , Humanos , Dióxido de Silicio , Caries Dental/prevención & control , Arginina , Streptococcus mutans , Cementos Dentales/farmacologíaRESUMEN
INTRODUCTION: Electrophysiological diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) may be challenging. Thus, with the aim ofproviding some practical advice in electrophysiological approach to a patient with suspected CIDP, we analyzed electrophysiological data from 499 patients enrolled inthe Italian CIDP Database. METHODS: We calculated the rate of each demyelinating feature, the rate of demyelinating features per nerve, the diagnostic rate for upper andlower limb nerves, and, using a ROC curve analysis, the diagnostic accuracy of each couple of nerves and each demyelinating feature, for every CIDP subtype.Moreover, we compared the electrophysiological data of definite and probable CIDP patients with those of possible and not-fulfilling CIDP patients, and by a logisticregression analysis, we estimated the odds ratio (OR) to make an electrophysiological diagnosis of definite or probable CIDP. RESULTS: The ulnar nerve had the highestrate of demyelinating features and, when tested bilaterally, had the highest diagnostic accuracy except for DADS in which peroneal nerves were the most informative.In possible and not-fulfilling CIDP patients, a lower number of nerves and proximal temporal dispersion (TD) measurements had been performed compared to definiteand probable CIDP patients. Importantly, OR for each tested motor nerve and each TD measurement was 1.59 and 1.33, respectively. CONCLUSION: Our findingsdemonstrated that the diagnosis of CIDP may be missed due to inadequate or incomplete electrophysiological examination or interpretation. At the same time, thesedata taken together could be useful to draw a thoughtful electrophysiological approach to patients suspected of CIDP.