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1.
Cell Tissue Res ; 392(2): 581-604, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36627392

RESUMO

Experimental autoimmune orchitis (EAO) is a chronic inflammatory disorder that causes progressive spermatogenic impairment. EAO is characterized by high intratesticular levels of nitric oxide (NO) and tumor necrosis factor alpha (TNFα) causing germ cell apoptosis and Sertoli cell dysfunction. However, the impact of this inflammatory milieu on the spermatogenic wave is unknown. Therefore, we studied the effect of inflammation on spermatogonia and preleptotene spermatocyte cell cycle progression in an EAO context and through the intratesticular DETA-NO and TNFα injection in the normal rat testes. In EAO, premeiotic germ cell proliferation is limited as a consequence of the undifferentiated spermatogonia (CD9+) cell cycle arrest in G2/M and the reduced number of differentiated spermatogonia (c-kit+) and preleptotene spermatocytes that enter in the meiotic S-phase. Although inflammation disrupts spermatogenesis in EAO, it is maintained in some seminiferous tubules at XIV and VII-VIII stages of the epithelial cell cycle, thereby guaranteeing sperm production. We found that DETA-NO (2 mM) injected in normal testes arrests spermatogonia and preleptotene spermatocyte cell cycle; this effect reduces the number of proliferative spermatogonia and the number of preleptotene spermatocytes in meiosis S-phase (36 h after). The temporal inhibition of spermatogonia clonal amplification delayed progression of the spermatogenic wave (5 days after) finally altering spermatogenesis. TNFα (0.5 and 1 µg) exposure did not affect premeiotic germ cell cycle or spermatogenic wave. Our results show that in EAO the inflammatory microenvironment altered spermatogenesis kinetics through premeiotic germ cell cycle arrest and that NO is a sufficient factor contributing to this phenomenon.


Assuntos
Orquite , Fator de Necrose Tumoral alfa , Ratos , Humanos , Animais , Masculino , Fator de Necrose Tumoral alfa/farmacologia , Sêmen , Espermatogênese/fisiologia , Espermatogônias , Testículo , Espermatócitos , Células de Sertoli/fisiologia , Inflamação/patologia
2.
Environ Microbiol ; 23(10): 5670-5689, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33939255

RESUMO

Productive plant-bacteria interactions, either beneficial or pathogenic, require that bacteria successfully sense, integrate and respond to continuously changing environmental and plant stimuli. They use complex signal transduction systems that control a vast array of genes and functions. The Gac-Rsm global regulatory pathway plays a key role in controlling fundamental aspects of the apparently different lifestyles of plant beneficial and phytopathogenic Pseudomonas as it coordinates adaptation and survival while either promoting plant health (biocontrol strains) or causing disease (pathogenic strains). Plant-interacting Pseudomonas stand out for possessing multiple Rsm proteins and Rsm RNAs, but the physiological significance of this redundancy is not yet clear. Strikingly, the components of the Gac-Rsm pathway and the controlled genes/pathways are similar, but the outcome of its regulation may be opposite. Therefore, identifying the target mRNAs bound by the Rsm proteins and their mode of action (repression or activation) is essential to explain the resulting phenotype. Some technical considerations to approach the study of this system are also given. Overall, several important features of the Gac-Rsm cascade are now understood in molecular detail, particularly in Pseudomonas protegens CHA0, but further questions remain to be solved in other plant-interacting Pseudomonas.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Pseudomonas/genética , Pseudomonas/metabolismo , RNA Mensageiro/genética , Transdução de Sinais/genética
3.
RNA Biol ; 18(11): 1818-1833, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33406981

RESUMO

The Gac-rsm pathway is a global regulatory network that governs mayor lifestyle and metabolic changes in gamma-proteobacteria. In a previous study, we uncovered the role of CsrA proteins promoting growth and repressing motility, alginate production and virulence in the model phytopathogen Pseudomonas syringae pv. tomato (Pto) DC3000. Here, we focus on the expression and regulation of the rsm regulatory sRNAs, since Pto DC3000 exceptionally has seven variants (rsmX1-5, rsmY and rsmZ). The presented results offer further insights into the functioning of the complex Gac-rsm pathway and the interplay among its components. Overall, rsm expressions reach maximum levels at high cell densities, are unaffected by surface detection, and require GacA for full expression. The rsm levels of expression and GacA-dependence are determined by the sequences found in their -35/-10 promoter regions and GacA binding boxes, respectively. rsmX5 stands out for being the only rsm in Pto DC3000 whose high expression does not require GacA, constituting the main component of the total rsm pool in a gacA mutant. The deletion of rsmY and rsmZ had minor effects on Pto DC3000 motility and virulence phenotypes, indicating that rsmX1-5 can functionally replace them. On the other hand, rsmY or rsmZ overexpression in a gacA mutant did not revert its phenotype. Additionally, a negative feedback regulatory loop in which the CsrA3 protein promotes its own titration by increasing the levels of several rsm RNAs in a GacA-dependent manner has been disclosed as part of this work.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Pseudomonas syringae/genética , RNA Bacteriano/genética , Pequeno RNA não Traduzido/genética , Proteínas de Bactérias/genética , Pseudomonas syringae/metabolismo , RNA Bacteriano/metabolismo , Pequeno RNA não Traduzido/metabolismo
4.
Cogn Affect Behav Neurosci ; 20(2): 356-370, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32048200

RESUMO

Human sociality and prosociality rely on social and moral feelings of empathy, compassion, envy, schadenfreude, as well as on the preference for prosocial over antisocial others. We examined the neural underpinnings of the processing of lexical input designed to tap into these type of social feelings. Brainwave responses from 20 participants were measured as they read sentences comprising a randomly delivered ending outcome (fortunate or unfortunate) to social agents previously profiled as prosocial or antisocial individuals. Fortunate outcomes delivered to prosocial and antisocial agents aimed to tap into empathy and envy/annoying feelings, respectively, whereas unfortunate ones into compassion for prosocial agents and schadenfreude for antisocial ones. ERP modulations in early attention-capture (100-200 ms), semantic fit (400 ms), and late reanalysis processes (600 ms) were analyzed. According to the functional interpretation of each of these event-related electrophysiological effects, we conclude that: 1) a higher capture of attention is initially obtained in response to any type of outcome delivered to a prosocial versus an antisocial agent (frontal P2); 2) a facilitated semantic processing occurs for unfortunate outcomes delivered to antisocial agents (N400); and 3) regardless of the protagonist's social profile, an increased later reevaluation for overall unfortunate versus fortunate outcomes takes place (Late Positive Potential). Thus, neural online measures capture a stepwise unfolding impact of social factors during language comprehension, which include a facilitated processing of misfortunes when they happen to occur to antisocial peers (i.e., schadenfreude).


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Encéfalo/fisiologia , Emoções/fisiologia , Empatia/fisiologia , Potenciais Evocados/fisiologia , Adolescente , Adulto , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Leitura , Comportamento Social , Adulto Jovem
5.
Age Ageing ; 49(4): 605-614, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32484850

RESUMO

BACKGROUND: Multi-morbidity and polypharmacy increase the risk of non-trivial adverse drug reactions (ADRs) in older people during hospitalization. Despite this, there are no established interventions for hospital-acquired ADR prevention. METHODS: We undertook a pragmatic, multi-national, parallel arm prospective randomized open-label, blinded endpoint (PROBE) controlled trial enrolling patients at six European medical centres. We randomized 1,537 older medical and surgical patients with multi-morbidity and polypharmacy on admission in a 1:1 ratio to SENATOR software-guided medication optimization plus standard care (intervention, n = 772, mean number of daily medications = 9.34) or standard care alone (control, n = 765, mean number of daily medications = 9.23) using block randomization stratified by site and admission type. Attending clinicians in the intervention arm received SENATOR-generated advice at a single time point with recommendations they could choose to adopt or not. The primary endpoint was occurrence of probable or certain ADRs within 14 days of randomization. Secondary endpoints were primary endpoint derivatives; tertiary endpoints included all-cause mortality, re-hospitalization, composite healthcare utilization and health-related quality of life. RESULTS: For the primary endpoint, there was no difference between the intervention and control groups (24.5 vs. 24.8%; OR 0.98; 95% CI 0.77-1.24; P = 0.88). Similarly, with secondary and tertiary endpoints, there were no significant differences. Among attending clinicians in the intervention group, implementation of SENATOR software-generated medication advice points was poor (~15%). CONCLUSIONS: In this trial, uptake of software-generated medication advice to minimize ADRs was poor and did not reduce ADR incidence during index hospitalization.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Polimedicação , Idoso , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Hospitalização , Humanos , Multimorbidade , Estudos Prospectivos , Qualidade de Vida
6.
Haematologica ; 104(3): 587-598, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30361419

RESUMO

Large studies in von Willebrand disease patients, including Spanish and Portuguese registries, led to the identification of >250 different mutations. It is a challenge to determine the pathogenic effect of potential splice site mutations on VWF mRNA. This study aimed to elucidate the true effects of 18 mutations on VWF mRNA processing, investigate the contribution of next-generation sequencing to in vivo mRNA study in von Willebrand disease, and compare the findings with in silico prediction. RNA extracted from patient platelets and leukocytes was amplified by RT-PCR and sequenced using Sanger and next generation sequencing techniques. Eight mutations affected VWF splicing: c.1533+1G>A, c.5664+2T>C and c.546G>A (p.=) prompted exon skipping; c.3223-7_3236dup and c.7082-2A>G resulted in activation of cryptic sites; c.3379+1G>A and c.7437G>A) demonstrated both molecular pathogenic mechanisms simultaneously; and the p.Cys370Tyr missense mutation generated two aberrant transcripts. Of note, the complete effect of three mutations was provided by next generation sequencing alone because of low expression of the aberrant transcripts. In the remaining 10 mutations, no effect was elucidated in the experiments. However, the differential findings obtained in platelets and leukocytes provided substantial evidence that four of these would have an effect on VWF levels. In this first report using next generation sequencing technology to unravel the effects of VWF mutations on splicing, the technique yielded valuable information. Our data bring to light the importance of studying the effect of synonymous and missense mutations on VWF splicing to improve the current knowledge of the molecular mechanisms behind von Willebrand disease. clinicaltrials.gov identifier:02869074.


Assuntos
Inativação Gênica , Íntrons , Mutação de Sentido Incorreto , Splicing de RNA , Fator de von Willebrand/genética , Alelos , Sequência de Bases , Plaquetas/metabolismo , Biologia Computacional , Éxons , Feminino , Frequência do Gene , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucócitos/metabolismo , Masculino , Sítios de Splice de RNA , RNA Mensageiro/genética , Doenças de von Willebrand/genética
7.
Mol Plant Microbe Interact ; 31(5): 525-536, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29261011

RESUMO

The phytopathogenic bacterium Pseudomonas syringae pv. tomato DC3000 has a complex Gac-rsm global regulatory pathway that controls virulence, motility, production of secondary metabolites, carbon metabolism, and quorum sensing. However, despite the fact that components of this pathway are known, their physiological roles have not yet been established. Regarding the CsrA/RsmA type proteins, five paralogs, three of which are well conserved within the Pseudomonas genus (csrA1, csrA2, and csrA3), have been found in the DC3000 genome. To decipher their function, mutants lacking the three most conserved CsrA proteins have been constructed and their physiological outcomes examined. We show that they exert nonredundant functions and demonstrate that CsrA3 and, to a lesser extent, CsrA2 but not CsrA1 alter the expression of genes involved in a variety of pathways and systems important for motility, exopolysaccharide synthesis, growth, and virulence. Particularly, alginate synthesis, syringafactin production, and virulence are considerably de-repressed in a csrA3 mutant, whereas growth in planta is impaired. We propose that the linkage of growth and symptom development is under the control of CsrA3, which functions as a pivotal regulator of the DC3000 life cycle, repressing virulence traits and promoting cell division in response to environmental cues.


Assuntos
Proteínas de Bactérias/metabolismo , Doenças das Plantas/microbiologia , Pseudomonas syringae/metabolismo , Pseudomonas syringae/patogenicidade , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Solanum lycopersicum/microbiologia , Phaseolus/microbiologia , Pseudomonas syringae/genética , Virulência
8.
Haematologica ; 102(12): 2005-2014, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28971901

RESUMO

Molecular diagnosis of patients with von Willebrand disease is pending in most populations due to the complexity and high cost of conventional molecular analyses. The need for molecular and clinical characterization of von Willebrand disease in Spain prompted the creation of a multicenter project (PCM-EVW-ES) that resulted in the largest prospective cohort study of patients with all types of von Willebrand disease. Molecular analysis of relevant regions of the VWF, including intronic and promoter regions, was achieved in the 556 individuals recruited via the development of a simple, innovative, relatively low-cost protocol based on microfluidic technology and next-generation sequencing. A total of 704 variants (237 different) were identified along VWF, 155 of which had not been previously recorded in the international mutation database. The potential pathogenic effect of these variants was assessed by in silico analysis. Furthermore, four short tandem repeats were analyzed in order to evaluate the ancestral origin of recurrent mutations. The outcome of genetic analysis allowed for the reclassification of 110 patients, identification of 37 asymptomatic carriers (important for genetic counseling) and re-inclusion of 43 patients previously excluded by phenotyping results. In total, 480 patients were definitively diagnosed. Candidate mutations were identified in all patients except 13 type 1 von Willebrand disease, yielding a high genotype-phenotype correlation. Our data reinforce the capital importance and usefulness of genetics in von Willebrand disease diagnostics. The progressive implementation of molecular study as the first-line test for routine diagnosis of this condition will lead to increasingly more personalized and effective care for this patient population.


Assuntos
Doenças de von Willebrand/genética , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Espanha/epidemiologia , Doenças de von Willebrand/diagnóstico , Fator de von Willebrand/genética
10.
Cyberpsychol Behav Soc Netw ; 27(4): 261-267, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38377604

RESUMO

This study aimed at exploring the association of nomophobia with alcohol, tobacco, and/or cannabis consumption among high school students. We carried out a cross-sectional study among high school and vocational training students in Galicia, Northwest Spain (N = 3,100). Collected data included nomophobia, sociodemographic variables, and alcohol, tobacco, and cannabis consumption. Nomophobia was measured using the validated Nomophobia Questionnaire. Adjusted odds ratios (ORs) and their 95 percent confidence intervals (CIs) were estimated using generalized linear mixed models. More than a quarter of the adolescents (27.7 percent) had nomophobia. We found an association between nomophobia and a high level of tobacco smoking in the last month in boys (OR = 2.16; 95 percent CI: 1.55-3.03). Nomophobia was also associated with higher odds of binge drinking in both genders (girls: OR = 1.86; 95 percent CI: 1.61-3.52; boys: OR = 2.29; 95 percent CI: 1.68-3.13) and with cannabis consumption in boys (OR = 1.74; 95 percent CI: 1.07-2.81). Our findings highlight the importance of a comprehensive investigation of the factors underlying alcohol, tobacco, and cannabis consumption in the adolescent population.


Assuntos
Consumo de Bebidas Alcoólicas , Humanos , Masculino , Adolescente , Feminino , Espanha/epidemiologia , Estudos Transversais , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Uso da Maconha/epidemiologia , Uso da Maconha/psicologia , Uso de Tabaco/epidemiologia , Uso de Tabaco/psicologia , Estudantes/estatística & dados numéricos , Estudantes/psicologia , Transtornos Fóbicos/epidemiologia , Transtornos Fóbicos/psicologia , Inquéritos e Questionários , Comportamento do Adolescente/psicologia
11.
Nat Neurosci ; 27(7): 1274-1284, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38773348

RESUMO

Retrotransposons are mobile DNA sequences duplicated via transcription and reverse transcription of an RNA intermediate. Cis-regulatory elements encoded by retrotransposons can also promote the transcription of adjacent genes. Somatic LINE-1 (L1) retrotransposon insertions have been detected in mammalian neurons. It is, however, unclear whether L1 sequences are mobile in only some neuronal lineages or therein promote neurodevelopmental gene expression. Here we report programmed L1 activation by SOX6, a transcription factor critical for parvalbumin (PV) interneuron development. Mouse PV interneurons permit L1 mobilization in vitro and in vivo, harbor unmethylated L1 promoters and express full-length L1 mRNAs and proteins. Using nanopore long-read sequencing, we identify unmethylated L1s proximal to PV interneuron genes, including a novel L1 promoter-driven Caps2 transcript isoform that enhances neuron morphological complexity in vitro. These data highlight the contribution made by L1 cis-regulatory elements to PV interneuron development and transcriptome diversity, uncovered due to L1 mobility in this milieu.


Assuntos
Interneurônios , Elementos Nucleotídeos Longos e Dispersos , Parvalbuminas , Animais , Interneurônios/metabolismo , Interneurônios/fisiologia , Camundongos , Elementos Nucleotídeos Longos e Dispersos/genética , Parvalbuminas/metabolismo , Retroelementos/genética , Masculino , Neurogênese/fisiologia , Neurogênese/genética , Camundongos Endogâmicos C57BL , Regulação da Expressão Gênica no Desenvolvimento/genética
12.
Trends Neurosci ; 46(6): 413-414, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37061454

RESUMO

How does neurodegeneration spread in the brain? Leveraging TDP-43 fly models of amyotrophic lateral sclerosis (ALS), Chang and Dubnau recently reported that the endogenous retrovirus (ERV) mdg4 can trigger and transmit TDP-43 proteinopathy in vivo. Their results suggest that human ERVs could be targeted to develop future ALS therapies.


Assuntos
Esclerose Lateral Amiotrófica , Retrovirus Endógenos , Proteinopatias TDP-43 , Humanos , Retrovirus Endógenos/genética , Esclerose Lateral Amiotrófica/genética , Proteinopatias TDP-43/genética , Encéfalo
13.
Polymers (Basel) ; 15(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38006093

RESUMO

Dendrimers constitute a distinctive category of synthetic materials that bear resemblance to proteins in various aspects, such as discrete structural organization, globular morphology, and nanoscale dimensions. Remarkably, these attributes coexist with the capacity for facile large-scale production. Due to these advantages, the realm of dendrimers has undergone substantial advancement since their inception in the 1980s. Numerous reviews have been dedicated to elucidating this subject comprehensively, delving into the properties and applications of quintessential dendrimer varieties like PAMAM, PPI, and others. Nevertheless, the contemporary landscape of dendrimers transcends these early paradigms, witnessing the emergence of a diverse array of novel dendritic architectures in recent years. In this review, we aim to present a comprehensive panorama of the expansive domain of dendrimers. As such, our focus lies in discussing the key attributes and applications of the predominant types of dendrimers existing today. We will commence with the conventional variants and progressively delve into the more pioneering ones, including Janus, supramolecular, shape-persistent, and rotaxane dendrimers.

14.
Cancers (Basel) ; 15(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958416

RESUMO

Metastatic colorectal cancer (mCRC) with mutated BRAF exhibits distinct biological and molecular features that set it apart from other subtypes of CRC. Current standard treatment for these tumors involves a combination of chemotherapy (CT) and VEGF inhibitors. Recently, targeted therapy against BRAF and immunotherapy (IT) for cases with microsatellite instability (MSI) have been integrated into clinical practice. While targeted therapy has shown promising results, resistance to treatment eventually develops in a significant portion of responsive patients. This article aims to review the available literature on mechanisms of resistance to BRAF inhibitors (BRAFis) and potential therapeutic strategies to overcome them.

15.
BMC Genomics ; 13: 483, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22978642

RESUMO

BACKGROUND: Neurodegenerative diseases are progressive and irreversible and they can be initiated by mutations in specific genes. Spalt-like genes (Sall) encode transcription factors expressed in the central nervous system. In humans, SALL mutations are associated with hereditary syndromes characterized by mental retardation, sensorineural deafness and motoneuron problems, among others. Drosophila sall mutants exhibit severe neurodegeneration of the central nervous system at embryonic stage 16, which surprisingly reverts later in development at embryonic stage 17, suggesting a potential to recover from neurodegeneration. We hypothesize that this recovery is mediated by a reorganization of the transcriptome counteracting SALL lost. To identify genes associated to neurodegeneration and neuroprotection, we used mRNA-Seq to compare the transcriptome of Drosophila sall mutant and wild type embryos from neurodegeneration and reversal stages. RESULTS: Neurodegeneration stage is associated with transcriptional changes in 220 genes, of which only 5% were already described as relevant for neurodegeneration. Genes related to the groups of Redox, Lifespan/Aging and Mitochondrial diseases are significantly represented at this stage. By contrast, neurodegeneration reversal stage is associated with significant changes in 480 genes, including 424 not previously associated with neuroprotection. Immune response and Salt stress are the most represented groups at this stage. CONCLUSIONS: We identify new genes associated to neurodegeneration and neuroprotection by using an mRNA-Seq approach. The strong homology between Drosophila and human genes raises the possibility to unveil novel genes involved in neurodegeneration and neuroprotection also in humans.


Assuntos
Proteínas de Drosophila/genética , Drosophila/genética , Doenças Neurodegenerativas/genética , Transcriptoma , Animais , Biologia Computacional , Drosophila/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Análise de Sequência de RNA
16.
Foods ; 11(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37430925

RESUMO

The most consumed cereal-based product worldwide is bread. "Caaveiro", an autochthonous variety with a recent growing interest, is one of the wheat varieties that fulfill the 25% local flour requirement in the PGI "Pan Galego" bread baking industry. The element content of the refined wheat flours used to make "Pan Galego" (''Caaveiro'', FCv; Castilla, FC; and a mixture of both, FM) was evaluated in ICP-MS. In addition, wholegrain flour (FWM) was included in the analysis. Loaves of bread were made with these flours (a, 100% FC; b, 100% FCv); and c, FM: 75% FC + 25% FCv) and their element content was analyzed. Wholegrain flour ranked the highest in almost all elements, highlighting the P (494.80 mg/100 g), while the FM and the FC presented the opposite behavior, with the highest Se values (14.4 and 15.8 mg/100 g, respectively). FCv was situated in an intermediate position regarding P, K, Mg, Mn, Zn, Fe and Na content, standing closer to FWM, although it presents the highest values for Cu (1076.3 µg/100 g). The differences observed in flour were maintained in bread. Hence, the local cultivar ''Caaveiro'' has an interesting nutritional profile from the point of view of the element content.

17.
Synapse ; 64(1): 14-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19725115

RESUMO

The morphology of Drosophila motor terminals changes along the day with a circadian rhythm controlled by the biological clock. Here, we used electron microscopy to investigate the size, number, and distribution of synaptic vesicles, at intervals of 6 h during 2 consecutive days, under light-dark (LD) or the first 2 days in constant darkness (DD). We found changes in the size and distribution of vesicles located either at the active zone or in the reserve pool, indicating a circadian rhythm of synapse reorganization. Vesicles at the active zone were generally smaller than those in the reserve pool in LD and DD conditions. The size of active zones vesicles decreased twice in LD, corresponding with times of more intense locomotion activity, but only once in DD conditions.


Assuntos
Ritmo Circadiano/fisiologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/ultraestrutura , Vesículas Sinápticas/fisiologia , Vesículas Sinápticas/ultraestrutura , Animais , Microscopia Eletrônica de Transmissão , Músculo Esquelético/fisiologia , Músculo Esquelético/ultraestrutura , Junção Neuromuscular/fisiologia , Junção Neuromuscular/ultraestrutura
18.
Thromb Haemost ; 120(3): 437-448, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32135566

RESUMO

The clinical diagnosis of von Willebrand disease (VWD), particularly type 1, can be complex because several genetic and environmental factors affect von Willebrand factor (VWF) plasma levels. An estimated 60% of the phenotypic variation is attributable to hereditary factors, with the ABO blood group locus being the most influential. However, recent studies provide strong evidence that nonsynonymous single nucleotide variants (SNVs) contribute to VWF and factor VIII phenotypic variability in healthy individuals. This study aims to investigate the role of common VWF SNVs on VWD phenotype by analyzing data from 219 unrelated patients included in the "Molecular and Clinical Profile of von Willebrand Disease in Spain project." To that end, generalized linear mixed-effects regression models were fitted, and additive and epistatic analyses, and haplotype studies were performed, considering five VWD-related measures (bleeding score, VWF:Ag, VWF:RCo, factor VIII:C, and VWF:CB). According to these analyses, homozygotes: for p.Thr789Ala(C) would be expected to show 39% higher VWF:Ag levels; p.Thr1381Ala(C), 27% lower VWF:Ag levels; and p.Gln852Arg(C), 52% lower VWF:RCo levels. Homozygotes for both p.Thr789Ala(C) and p.Gln852Arg(T) were predicted to show 185% higher VWF:CB activity, and carriers of two copies of the p.Thr1381Ala(T)/p.Gln852Arg(T) haplotype would present a 100% increase in VWF:RCo activity. These results indicate a substantial effect of common VWF variation on VWD phenotype. Although additional studies are needed to determine the true magnitude of the effects of SNVs on VWF, these findings provide new evidence regarding the contribution of common variants to VWD, which should be taken into account to enhance the accuracy of the diagnosis and classification of this condition. ClinicalTrials.gov identifier: NCT02869074.


Assuntos
Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Doenças de von Willebrand/sangue , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Adulto , Simulação por Computador , Fator VIII/genética , Fator VIII/metabolismo , Feminino , Haplótipos , Hemorragia , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Sistema de Registros , Análise de Regressão , Espanha , Adulto Jovem , Fator de von Willebrand/química
19.
Front Microbiol ; 10: 746, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057500

RESUMO

Pseudomonas syringae pv. tomato DC3000 carries the wssABCDEFGHI operon for the synthesis of acetylated cellulose, whose production is stimulated by increasing the intracellular levels of the second messenger c-di-GMP. This enhances air-liquid biofilm formation and generates a wrinkly colony morphotype in solid media. In the present study we show that cellulose production is a complex process regulated at multiple levels and involving different players in this bacterium. Using different in vitro approaches, including Electrophoretic Mobility Shift Assay (EMSA) and footprint analysis, we demonstrated the interrelated role of two transcriptional regulators, AmrZ and FleQ, over cellulose production in Pto DC3000 and the influence of c-di-GMP in this process. Under physiological c-di-GMP levels, both regulators bind directly to adjacent regions at the wss promoter inhibiting its expression. However, just FleQ responds to c-di-GMP releasing from its wss operator site and converting from a repressor to an activator of cellulose production. The additive effect of the double amrZ/fleQ mutation on the expression of wss, together with the fact that they are not cross-regulated at the transcriptional level, suggest that FleQ and AmrZ behave as independent regulators, unlike what has been described in other Pseudomonas species. Furthermore, this dual co-regulation exerted by AmrZ and FleQ is not limited to cellulose production, but also affects other important phenotypes in Pto DC3000, such as motility and virulence.

20.
Reprod Biol ; 19(4): 329-339, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31757605

RESUMO

During an inflammatory process of the testis, the network of somatic, immune, and germ cell interactions is altered leading to organ dysfunction. In testicular biopsies of infertile men, spermatogenesis impairment is associated with reduced spermatogonia proliferation, increased number of immune cells, and content of pro-inflammatory cytokines. TNFα-TNFR and nitric oxide (NO)-NO synthase systems are up-regulated in models of testicular damage and in human testis with maturation arrest. The purpose of this study was to test the hypothesis that TNFα-TNFR system and NO alter the function of spermatogonia in the inflamed testis. We studied the effect of TNFα and NO on GC-1 spermatogonia cell cycle progression and death by flow cytometry. GC-1 cells expressed TNFR1 and TNFR2 (immunofluorescence). TNFα (10 and 50 ng/ml) and DETA-Nonoate (0.5 and 2 mM), a NO releaser, increased the percentage of cells in S-phase of the cell cycle and reduced the percentage in G1, inducing also cell apoptosis. TNFα effect was not mediated by oxidative stress unlike NO, since the presence of N-acetyl-l-cysteine (2.5 and 5.0 mM) prevented NO induced cell cycle arrest and death. GC-1 spermatogonia overpass NO induced cell cycle arrest but no TNFα, since after removal of NO, spermatogonia progressed through the cell cycle. We propose TNFα and NO might contribute to impairment of spermatogenesis by preventing adequate functioning of the spermatogonia population. Our results showed that TNFα and NO impaired spermatogonia cell cycle, inducing GC-1 arrest in the S phase.


Assuntos
Inflamação/fisiopatologia , Óxido Nítrico/fisiologia , Espermatogônias/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Apoptose , Ciclo Celular , Linhagem Celular , Humanos , Masculino , Estresse Oxidativo , Receptores do Fator de Necrose Tumoral/metabolismo , Espermatogênese
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