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1.
Ann Neurol ; 95(2): 365-376, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37964487

RESUMO

OBJECTIVE: Variants in several potassium channel genes, including KCNA1 and KCNA2, cause Developmental and Epileptic Encephalopathies (DEEs). We investigated whether variants in KCNA3, another mammalian homologue of the Drosophila shaker family and encoding for Kv1.3 subunits, can cause DEE. METHODS: Genetic analysis of study individuals was performed by routine exome or genome sequencing, usually of parent-offspring trios. Phenotyping was performed via a standard clinical questionnaire. Currents from wild-type and/or mutant Kv1.3 subunits were investigated by whole-cell patch-clamp upon their heterologous expression. RESULTS: Fourteen individuals, each carrying a de novo heterozygous missense variant in KCNA3, were identified. Most (12/14; 86%) had DEE with marked speech delay with or without motor delay, intellectual disability, epilepsy, and autism spectrum disorder. Functional analysis of Kv1.3 channels carrying each variant revealed heterogeneous functional changes, ranging from "pure" loss-of-function (LoF) effects due to faster inactivation kinetics, depolarized voltage-dependence of activation, slower activation kinetics, increased current inactivation, reduced or absent currents with or without dominant-negative effects, to "mixed" loss- and gain-of-function (GoF) effects. Compared to controls, Kv1.3 currents in lymphoblasts from 1 of the proband displayed functional changes similar to those observed upon heterologous expression of channels carrying the same variant. The antidepressant drug fluoxetine inhibited with similar potency the currents from wild-type and 1 of the Kv1.3 GoF variant. INTERPRETATION: We describe a novel association of de novo missense variants in KCNA3 with a human DEE, and provide evidence that fluoxetine might represent a potential targeted treatment for individuals carrying variants with significant GoF effects. ANN NEUROL 2024;95:365-376.


Assuntos
Transtorno do Espectro Autista , Epilepsia Generalizada , Epilepsia , Animais , Humanos , Fluoxetina , Epilepsia/tratamento farmacológico , Epilepsia/genética , Epilepsia/complicações , Mutação de Sentido Incorreto/genética , Mamíferos , Canal de Potássio Kv1.3/genética
2.
Proc Natl Acad Sci U S A ; 119(15): e2116887119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377796

RESUMO

Developmental and epileptic encephalopathies (DEEs) are neurodevelopmental diseases characterized by refractory epilepsy, distinct electroencephalographic and neuroradiological features, and various degrees of developmental delay. Mutations in KCNQ2, KCNQ3, and, more rarely, KCNQ5 genes encoding voltage-gated potassium channel subunits variably contributing to excitability control of specific neuronal populations at distinct developmental stages have been associated to DEEs. In the present work, the clinical features of two DEE patients carrying de novo KCNQ5 variants affecting the same residue in the pore region of the Kv7.5 subunit (G347S/A) are described. The in vitro functional properties of channels incorporating these variants were investigated with electrophysiological and biochemical techniques to highlight pathophysiological disease mechanisms. Currents carried by Kv7.5 G347 S/A channels displayed: 1) large (>10 times) increases in maximal current density, 2) the occurrence of a voltage-independent component, 3) slower deactivation kinetics, and 4) hyperpolarization shift in activation. All these functional features are consistent with a gain-of-function (GoF) pathogenetic mechanism. Similar functional changes were also observed when the same variants were introduced at the corresponding position in Kv7.2 subunits. Nonstationary noise analysis revealed that GoF effects observed for both Kv7.2 and Kv7.5 variants were mainly attributable to an increase in single-channel open probability, without changes in membrane abundance or single-channel conductance. The mutation-induced increase in channel opening probability was insensitive to manipulation of membrane levels of the critical Kv7 channel regulator PIP2. These results reveal a pathophysiological mechanism for KCNQ5-related DEEs, which might be exploited to implement personalized treatments.


Assuntos
Epilepsia Resistente a Medicamentos , Mutação com Ganho de Função , Canais de Potássio KCNQ , Adolescente , Criança , Epilepsia Resistente a Medicamentos/genética , Feminino , Humanos , Canais de Potássio KCNQ/genética , Masculino , Mutação , Fenótipo , Probabilidade
3.
Clin Infect Dis ; 78(2): 248-258, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-37738153

RESUMO

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAb) is 1 of the most problematic antimicrobial-resistant bacteria. We sought to elucidate the international epidemiology and clinical impact of CRAb. METHODS: In a prospective observational cohort study, 842 hospitalized patients with a clinical CRAb culture were enrolled at 46 hospitals in five global regions between 2017 and 2019. The primary outcome was all-cause mortality at 30 days from the index culture. The strains underwent whole-genome analysis. RESULTS: Of 842 cases, 536 (64%) represented infection. By 30 days, 128 (24%) of the infected patients died, ranging from 1 (6%) of 18 in Australia-Singapore to 54 (25%) of 216 in the United States and 24 (49%) of 49 in South-Central America, whereas 42 (14%) of non-infected patients died. Bacteremia was associated with a higher risk of death compared with other types of infection (40 [42%] of 96 vs 88 [20%] of 440). In a multivariable logistic regression analysis, bloodstream infection and higher age-adjusted Charlson comorbidity index were independently associated with 30-day mortality. Clonal group 2 (CG2) strains predominated except in South-Central America, ranging from 216 (59%) of 369 in the United States to 282 (97%) of 291 in China. Acquired carbapenemase genes were carried by 769 (91%) of the 842 isolates. CG2 strains were significantly associated with higher levels of meropenem resistance, yet non-CG2 cases were over-represented among the deaths compared with CG2 cases. CONCLUSIONS: CRAb infection types and clinical outcomes differed significantly across regions. Although CG2 strains remained predominant, non-CG2 strains were associated with higher mortality. Clinical Trials Registration. NCT03646227.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Humanos , Acinetobacter baumannii/genética , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Estudos Prospectivos , Testes de Sensibilidade Microbiana , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , beta-Lactamases/genética , Proteínas de Bactérias/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
4.
Development ; 148(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33757992

RESUMO

The thyroid hormone T3 and its nuclear receptor TRα1 control gut development and homeostasis through the modulation of intestinal crypt cell proliferation. Despite increasing data, in-depth analysis on their specific action on intestinal stem cells is lacking. By using ex vivo 3D organoid cultures and molecular approaches, we observed early responses to T3 involving the T3-metabolizing enzyme Dio1 and the transporter Mct10, accompanied by a complex response of stem cell- and progenitor-enriched genes. Interestingly, specific TRα1 loss-of-function (inducible or constitutive) was responsible for low ex vivo organoid development and impaired stem cell activity. T3 treatment of animals in vivo not only confirmed the positive action of this hormone on crypt cell proliferation but also demonstrated its key action in modulating the number of stem cells, the expression of their specific markers and the commitment of progenitors into lineage-specific differentiation. In conclusion, T3 treatment or TRα1 modulation has a rapid and strong effect on intestinal stem cells, broadening our perspectives in the study of T3/TRα1-dependent signaling in these cells.


Assuntos
Proliferação de Células , Intestinos , Transdução de Sinais , Células-Tronco/metabolismo , Receptores alfa dos Hormônios Tireóideos/metabolismo , Tri-Iodotironina/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Animais , Feminino , Iodeto Peroxidase/genética , Iodeto Peroxidase/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Células-Tronco/citologia , Receptores alfa dos Hormônios Tireóideos/genética , Tri-Iodotironina/genética
5.
BMC Med ; 22(1): 127, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38500180

RESUMO

BACKGROUND: While the augmented incidence of diabetes after COVID-19 has been widely confirmed, controversial results are available on the risk of developing hypertension during the COVID-19 pandemic. METHODS: We designed a longitudinal cohort study to analyze a closed cohort followed up over a 7-year period, i.e., 3 years before and 3 years during the COVID-19 pandemic, and during 2023, when the pandemic was declared to be over. We analyzed medical records of more than 200,000 adults obtained from a cooperative of primary physicians from January 1, 2017, to December 31, 2023. The main outcome was the new diagnosis of hypertension. RESULTS: We evaluated 202,163 individuals in the pre-pandemic years and 190,743 in the pandemic years, totaling 206,857 when including 2023 data. The incidence rate of new hypertension was 2.11 (95% C.I. 2.08-2.15) per 100 person-years in the years 2017-2019, increasing to 5.20 (95% C.I. 5.14-5.26) in the period 2020-2022 (RR = 2.46), and to 6.76 (95% C.I. 6.64-6.88) in 2023. The marked difference in trends between the first and the two successive observation periods was substantiated by the fitted regression lines of two Poisson models conducted on the monthly log-incidence of hypertension. CONCLUSIONS: We detected a significant increase in new-onset hypertension during the COVID-19 pandemic, which at the end of the observation period affected ~ 20% of the studied cohort, a percentage higher than the diagnosis of COVID-19 infection within the same time frame. This observation suggests that increased attention to hypertension screening should not be limited to individuals who are aware of having contracted the infection but should be extended to the entire population.


Assuntos
COVID-19 , Hipertensão , Adulto , Humanos , Estudos Longitudinais , Incidência , Pandemias , COVID-19/epidemiologia , Estudos de Coortes , Hipertensão/epidemiologia
6.
J Pharmacol Exp Ther ; 388(3): 742-747, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37775305

RESUMO

Recent studies have yielded controversial results on the long-term effects of statins on the risk of cardiovascular (CV) events. To fill this knowledge gap, we assessed the relationship between low-density lipoprotein cholesterol (LDL-C) levels and CV events in hypertensive patients without previous CV events and naïve to antidyslipidemic treatment within the "Campania Salute Network" in Southern Italy. We studied 725 hypertensive patients with a mean follow-up of 85.4 ± 25.7 months. We stratified our cohort into three groups based on LDL cholesterol (LDL-C) levels in mg/dl: group 1) patients showing during the follow-up a mean LDL-C value ≤100 mg/dl in absence of statin therapy; group 2) statin-treated patients with LDL ≤100 mg/dl; and group 3) patients with LDL-C >100 mg/dl. No significant difference among the groups was observed in terms of demographic and clinical characteristics and medications. The incidence of first CV events was 5.7% in group 1, 6.0% in group 2, and 11.9% in group 3 (P < 0.05 vs. group 1 and group 2). A stable long-term satisfactory control of LDL-C plasma concentration (≤100 mg/dl) reduced the incidence of major CV events from one event every 58.6 patients per year to one event every 115.9 patients per year. These findings were confirmed in a Cox regression analysis, adjusting for potential confounding factors. Collectively, our data demonstrate that a 7-year stable control of LDL-C reduces the incidence of CV events by 40%. SIGNIFICANCE STATEMENT: There are several discrepancies between Mendelian studies and other investigations concerning the actual effects of reduction of plasma concentration of low-density lipoprotein (LDL) cholesterol on the incidence of major cardiovascular events. Taken together, our data in nondiabetic subjects show that a 7-year stable control of LDL cholesterol induces a ∼40% reduction of the incidence of cardiovascular events.


Assuntos
Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipertensão , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , LDL-Colesterol/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Incidência , Colesterol , Hipertensão/tratamento farmacológico
7.
J Pharmacol Exp Ther ; 390(1): 4-10, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38135511

RESUMO

Background: Recent reports have evidenced an increased mortality rate in hypertensive patients with electrocardiographic left ventricular hypertrophy (ECG-LVH) achieving systolic blood pressure (SBP) <130 mmHg. However, to the best of our knowledge, the actual effects of blood pressure reduction to the ≤130/80 mmHg target on the incidence of cardiovascular (CV) events have never been determined in hypertensive patients with a diagnosis of left ventricular hypertrophy based on echocardiographic criteria (Echo-LVH). Methods: To fill this long-standing knowledge gap, we harnessed a population of 9511 hypertensive patients, followed-up for 33.6 [interquartile range 7.9-72.7] months. The population was divided into six groups according to the average SBP achieved during the follow-up (≤130, 130-139, and ≥140 mmHg) and absence/presence of Echo-LVH. The primary endpoint was a composite of fatal or nonfatal myocardial infarction and stroke, sudden cardiac death, heart failure requiring hospitalization, revascularization, and carotid stenting. Secondary endpoints included atrial fibrillation and transient ischemic attack. Results: During the follow-up, achieved SBP and diastolic blood pressure (DBP) were comparable between patients with and without Echo-LVH. Strikingly, the rates of primary and secondary endpoints were significantly higher in patients with Echo-LVH and SBP >130 mmHg, reaching the highest values in the Echo-LVH group with SBP ≥140 mmHg. By separate Cox multivariable regressions, after adjusting for potential confounders, both primary and secondary endpoints were significantly associated with SBP ≥140 mmHg and Echo-LVH. Instead, DBP reduction ≤80 mmHg was associated with a significant increased rate of secondary events. Conclusions: In hypertensive patients with Echo-LVH, achieving an average in-treatment SBP target ≤130 mmHg has a beneficial prognostic impact on incidence of CV events. SIGNIFICANCE STATEMENT: Contrary to recent findings, achieving in-treatment SBP ≤130 mmHg lowers the incidence of CV events in hypertensive patients with Echo-LVH. However, reducing DBP ≤80 mmHg is linked to increased CV complications. Cox multivariable regression models, considering potential confounders, reveal that the rate of hard and soft CV events is significantly associated with Echo-LVH and SBP ≥140 mmHg. Our data indicate that therapeutic strategies for Echo-LVH patients should target SBP ≤130 mmHg while avoiding lowering DBP ≤80 mmHg.


Assuntos
Pressão Sanguínea , Ecocardiografia , Hipertensão , Hipertrofia Ventricular Esquerda , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Feminino , Hipertensão/complicações , Hipertensão/fisiopatologia , Hipertensão/epidemiologia , Pessoa de Meia-Idade , Ecocardiografia/métodos , Incidência , Idoso , Sístole , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Seguimentos
8.
J Pharmacol Exp Ther ; 389(1): 34-39, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38336381

RESUMO

Emerging evidence indicates that the relationship between coronavirus disease 2019 (COVID-19) and diabetes is 2-fold: 1) it is known that the presence of diabetes and other metabolic alterations poses a considerably high risk to develop a severe COVID-19; 2) patients who survived a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have an increased risk of developing new-onset diabetes. However, the mechanisms underlying this association are mostly unknown, and there are no reliable biomarkers to predict the development of new-onset diabetes. In the present study, we demonstrate that a specific microRNA (miR-34a) contained in circulating extracellular vesicles released by endothelial cells reliably predicts the risk of developing new-onset diabetes in COVID-19. This association was independent of age, sex, body mass index (BMI), hypertension, dyslipidemia, smoking status, and D-dimer. SIGNIFICANCE STATEMENT: We demonstrate for the first time that a specific microRNA (miR-34a) contained in circulating extracellular vesicles released by endothelial cells is able to reliably predict the risk of developing diabetes after having contracted coronavirus disease 2019 (COVID-19). This association was independent of age, sex, body mass index (BMI), hypertension, dyslipidemia, smoking status, and D-dimer. Our findings are also relevant when considering the emerging importance of post-acute sequelae of COVID-19, with systemic manifestations observed even months after viral negativization (long COVID).


Assuntos
COVID-19 , Diabetes Mellitus , Dislipidemias , Hipertensão , MicroRNAs , Humanos , COVID-19/complicações , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Células Endoteliais , Progressão da Doença
9.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34498670

RESUMO

With the consolidation of deep learning in drug discovery, several novel algorithms for learning molecular representations have been proposed. Despite the interest of the community in developing new methods for learning molecular embeddings and their theoretical benefits, comparing molecular embeddings with each other and with traditional representations is not straightforward, which in turn hinders the process of choosing a suitable representation for Quantitative Structure-Activity Relationship (QSAR) modeling. A reason behind this issue is the difficulty of conducting a fair and thorough comparison of the different existing embedding approaches, which requires numerous experiments on various datasets and training scenarios. To close this gap, we reviewed the literature on methods for molecular embeddings and reproduced three unsupervised and two supervised molecular embedding techniques recently proposed in the literature. We compared these five methods concerning their performance in QSAR scenarios using different classification and regression datasets. We also compared these representations to traditional molecular representations, namely molecular descriptors and fingerprints. As opposed to the expected outcome, our experimental setup consisting of over $25 000$ trained models and statistical tests revealed that the predictive performance using molecular embeddings did not significantly surpass that of traditional representations. Although supervised embeddings yielded competitive results compared with those using traditional molecular representations, unsupervised embeddings tended to perform worse than traditional representations. Our results highlight the need for conducting a careful comparison and analysis of the different embedding techniques prior to using them in drug design tasks and motivate a discussion about the potential of molecular embeddings in computer-aided drug design.


Assuntos
Algoritmos , Relação Quantitativa Estrutura-Atividade
10.
Appl Environ Microbiol ; 90(5): e0024224, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38690890

RESUMO

Ralstonia solanacearum species complex (RSSC) is a phytopathogenic bacterial group that causes bacterial wilt in several crops, being potato (Solanum tuberosum) one of the most important hosts. The relationship between the potato plant ionome (mineral and trace elements composition) and the resistance levels to this pathogen has not been addressed until now. Mineral content of xylem sap, roots, stems and leaves of potato genotypes with different levels of resistance to bacterial wilt was assessed in this work, revealing a positive correlation between divalent calcium (Ca) cation concentrations and genotype resistance. The aim of this study was to investigate the effect of Ca on bacterial wilt resistance, and on the growth and virulence of RSSC. Ca supplementation significantly decreased the growth rate of Ralstonia pseudosolanacearum GMI1000 in minimal medium and affected several virulence traits such as biofilm formation and twitching motility. We also incorporate for the first time the use of microfluidic chambers to follow the pathogen growth and biofilm formation in conditions mimicking the plant vascular system. By using this approach, a reduction in biofilm formation was observed when both, rich and minimal media, were supplemented with Ca. Assessment of the effect of Ca amendments on bacterial wilt progress in potato genotypes revealed a significant delay in disease progress, or a complete absence of wilting symptoms in the case of partially resistant genotypes. This work contributes to the understanding of Ca effect on virulence of this important pathogen and provides new strategies for an integrated control of bacterial wilt on potato. IMPORTANCE: Ralstonia solanacearum species complex (RSSC) includes a diverse group of bacterial strains that cause bacterial wilt. This disease is difficult to control due to pathogen aggressiveness, persistence, wide range of hosts, and wide geographic distribution in tropical, subtropical, and temperate regions. RSSC causes considerable losses depending on the pathogen strain, host, soil type, environmental conditions, and cultural practices. In potato, losses of $19 billion per year have been estimated for this pathogen worldwide. In this study, we report for the first time the mineral composition found in xylem sap and plant tissues of potato germplasm with different levels of resistance to bacterial wilt. This study underscores the crucial role of calcium (Ca) concentration in the xylem sap and stem in relation to the resistance of different genotypes. Our in vitro experiments provide evidence of Ca's inhibitory effect on the growth, biofilm formation, and twitching movement of the model RSSC strain R. pseudosolanacearum GMI1000. This study introduces a novel element, the Ca concentration, which should be included into the integrated disease control management strategies for bacterial wilt in potatoes.


Assuntos
Cálcio , Doenças das Plantas , Ralstonia solanacearum , Solanum tuberosum , Solanum tuberosum/microbiologia , Doenças das Plantas/microbiologia , Cálcio/metabolismo , Ralstonia solanacearum/fisiologia , Ralstonia solanacearum/genética , Ralstonia solanacearum/patogenicidade , Ralstonia solanacearum/crescimento & desenvolvimento , Virulência , Biofilmes/crescimento & desenvolvimento , Ralstonia/genética , Ralstonia/fisiologia , Raízes de Plantas/microbiologia , Xilema/microbiologia
11.
Ann Neurol ; 94(2): 332-349, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37062836

RESUMO

OBJECTIVE: Pathogenic variants in KCNT2 are rare causes of developmental epileptic encephalopathy (DEE). We herein describe the phenotypic and genetic features of patients with KCNT2-related DEE, and the in vitro functional and pharmacological properties of KCNT2 channels carrying 14 novel or previously untested variants. METHODS: Twenty-five patients harboring KCNT2 variants were investigated: 12 were identified through an international collaborative network, 13 were retrieved from the literature. Clinical data were collected and included in a standardized phenotyping sheet. Novel variants were detected using exome sequencing and classified using ACMG criteria. Functional and pharmacological studies were performed by whole-cell electrophysiology in HEK-293 and SH-SY5Y cells. RESULTS: The phenotypic spectrum encompassed: (a) intellectual disability/developmental delay (21/22 individuals with available information), ranging from mild to severe/profound; (b) epilepsy (15/25); (c) neurological impairment, with altered muscle tone (14/22); (d) dysmorphisms (13/20). Nineteen pathogenic KCNT2 variants were found (9 new, 10 reported previously): 16 missense, 1 in-frame deletion of a single amino acid, 1 nonsense, and 1 frameshift. Among tested variants, 8 showed gain-of-function (GoF), and 6 loss-of-function (LoF) features when expressed heterologously in vitro. Quinidine and fluoxetine blocked all GoF variants, whereas loxapine and riluzole activated some LoF variants while blocking others. INTERPRETATION: We expanded the phenotypic and genotypic spectrum of KCNT2-related disorders, highlighting novel genotype-phenotype associations. Pathogenic KCNT2 variants cause GoF or LoF in vitro phenotypes, and each shows a unique pharmacological profile, suggesting the need for in vitro functional and pharmacological investigation to enable targeted therapies based on the molecular phenotype. ANN NEUROL 2023;94:332-349.


Assuntos
Deficiência Intelectual , Neuroblastoma , Humanos , Células HEK293 , Fenótipo , Genótipo , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/genética , Canais de Potássio Ativados por Sódio/genética
12.
PLoS Comput Biol ; 19(6): e1011196, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37384797

RESUMO

Intestinal epithelial cells play important roles in the absorption of nutrients, secretion of electrolytes and food digestion. The function of these cells is strongly influenced by purinergic signalling activated by extracellular ATP (eATP) and other nucleotides. The activity of several ecto-enzymes determines the dynamic regulation of eATP. In pathological contexts, eATP may act as a danger signal controlling a variety of purinergic responses aimed at defending the organism from pathogens present in the intestinal lumen. In this study, we characterized the dynamics of eATP on polarized and non-polarized Caco-2 cells. eATP was quantified by luminometry using the luciferin-luciferase reaction. Results show that non-polarized Caco-2 cells triggered a strong but transient release of intracellular ATP after hypotonic stimuli, leading to low micromolar eATP accumulation. Subsequent eATP hydrolysis mainly determined eATP decay, though this effect could be counterbalanced by eATP synthesis by ecto-kinases kinetically characterized in this study. In polarized Caco-2 cells, eATP showed a faster turnover at the apical vs the basolateral side. To quantify the extent to which different processes contribute to eATP regulation, we created a data-driven mathematical model of the metabolism of extracellular nucleotides. Model simulations showed that eATP recycling by ecto-AK is more efficient a low micromolar eADP concentrations and is favored by the low eADPase activity of Caco-2 cells. Simulations also indicated that a transient eATP increase could be observed upon the addition of non-adenine nucleotides due the high ecto-NDPK activity in these cells. Model parameters showed that ecto-kinases are asymmetrically distributed upon polarization, with the apical side having activity levels generally greater in comparison with the basolateral side or the non-polarized cells. Finally, experiments using human intestinal epithelial cells confirmed the presence of functional ecto-kinases promoting eATP synthesis. The adaptive value of eATP regulation and purinergic signalling in the intestine is discussed.


Assuntos
Trifosfato de Adenosina , Células Epiteliais , Humanos , Trifosfato de Adenosina/metabolismo , Células CACO-2 , Células Epiteliais/metabolismo , Proteínas de Transferência de Fosfolipídeos
13.
Malar J ; 23(1): 93, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575935

RESUMO

BACKGROUND: Plasmodium ovale malaria is usually considered a tropical infectious disease associated with low morbidity and mortality. However, severe disease and death have previously been reported. CASE PRESENTATION: A case of severe P. ovale malaria in a healthy Caucasian man with a triangle splenic infarction and clinical progression towards Acute Respiratory Distress Syndrome was reported despite a rapid response to oral chloroquine treatment with 24-h parasitaemia clearance. CONCLUSION: Plasmodium ovale malaria is generally considered as a benign disease, with low parasitaemia. However, severe disease and death have occasionally been reported. It is important to be aware that occasionally it can progress to serious illness and death even in immunocompetent individuals.


Assuntos
Antimaláricos , Malária , Plasmodium ovale , Síndrome do Desconforto Respiratório , Infarto do Baço , Masculino , Humanos , Antimaláricos/uso terapêutico , Infarto do Baço/diagnóstico , Infarto do Baço/complicações , Infarto do Baço/tratamento farmacológico , Malária/complicações , Malária/diagnóstico , Malária/tratamento farmacológico , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/etiologia , Itália
14.
Phys Chem Chem Phys ; 26(15): 11933-11944, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38572727

RESUMO

This study explores how water content modulates the self-assembly and fluorescence behavior of a novel calixarene, C1. C1 forms large, flattened structures in pure THF, but water addition triggers a transition to smaller, unimodal clusters. A critical micellar concentration (CMC) is identified, decreasing with increasing water content. Fluorescence quenching is observed upon water addition, attributed to nonradiative deactivation. These findings highlight water as a key regulator of C1's assembly and fluorescence, paving the way for further development of water-responsive calixarene systems.

15.
Cell Mol Life Sci ; 80(12): 365, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982870

RESUMO

The aim of this review article is to focus on the unconventional roles of epigenetic players (chromatin remodelers and long non-coding RNAs) in cell division, beyond their well-characterized functions in chromatin regulation during cell differentiation and development. In the last two  decades, diverse experimental evidence has shown that subunits of SRCAP and p400/TIP60 chromatin remodeling complexes in humans relocate from interphase nuclei to centrosomes, spindle or midbody, with their depletion yielding an array of aberrant outcomes of mitosis and cytokinesis. Remarkably, this behavior is shared by orthologous subunits of the Drosophila melanogaster DOM/TIP60 complex, despite fruit flies and humans diverged over 700 million years ago. In short, the available data support the view that subunits of these complexes are a new class of moonlighting proteins, in that they lead a "double life": during the interphase, they function in chromatin regulation within the nucleus, but as the cell progresses through mitosis, they interact with established mitotic factors, thus becoming integral components of the cell division apparatus.  By doing so, they contribute to ensuring the correct distribution of chromosomes in the two daughter cells and, when dysfunctional, can cause genomic instability, a condition that can trigger tumorigenesis and developmental diseases. Research over the past few years has unveiled a major contribution of long non-coding RNAs (lncRNAs) in the epigenetics regulation of gene expression which also impacts on cell division control. Here, we focus on possible structural roles of lncRNAs in the execution of cytokinesis: in particular, we suggest that specific classes of lncRNAs relocate to the midbody to form an architectural scaffold ensuring its proper assembly and function during abscission. Drawing attention to experimental evidence for non-canonical extranuclear roles of chromatin factors and lncRNAs has direct implications on important and novel aspects concerning both the epigenetic regulation and the evolutionary dynamics of cell division with a significant impact on differentiation, development, and diseases.


Assuntos
Cromatina , RNA Longo não Codificante , Humanos , Animais , Cromatina/genética , RNA Longo não Codificante/genética , Drosophila melanogaster/genética , Epigênese Genética , Mitose/genética , Drosophila
16.
Rev Argent Microbiol ; 56(1): 90-101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37923699

RESUMO

The aim of this study was to evaluate the protective effect of the encapsulation of Limosilactobacillus reuteri DSPV002C in macrocapsules made from industrial materials during production, storage and under simulated gastrointestinal conditions in vitro and in vivo. The production of macrocapsules involved the evaluation of different wall materials (matrix), namely, gelatin and pregelatinized starch, different inoculums, matrix ratios, and diverse cryoprotectants (whey permeate and maltodextrin). The different macrocapsules were arranged in molds of similar size to pig pelleted food and lyophilized. Then, the viability of the macrocapsules was assessed over time during storage at different temperatures (freezing, refrigeration and room temperature) and atmospheres (vacuum and non-vaccum). The macrocapsules with 10% w/v gelatin+5% w/v pregelatinized starch, permeated (10%, w/v), with a 9:1 inoculum:matrix ratio (GS7.5P9), stored under freezing conditions and vacuum, exhibited the highest viability of L. reuteri DSPV002C (9.3 log CFU/cap until 210 d). Under simulated gastrointestinal conditions, the encapsulated inoculum showed less viability loss (0.58±0.09 log CFU/ml, 26.53%), compared to the free culture (1.56±0.16 log CFU/ml, 2.85%). Finally, by administering GS7.5P9 to pigs, the tolerance of the bacteria to the gastrointestinal environment was verified, with viable counts equal to or greater than 3.72 log CFU/g of fecal matter throughout the trial. In this study, a high-density carrier probiotic macrocapsule of L. reuteri DSPV002C was obtained, which displayed a long shelf life, a suitable shape to be included in pig feed and an adequate survival of viable cells at the site of action.


Assuntos
Limosilactobacillus reuteri , Probióticos , Animais , Suínos , Gelatina , Suplementos Nutricionais , Amido
17.
J Infect Dis ; 227(6): 780-787, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36546706

RESUMO

BACKGROUND: Cross-neutralizing capacity of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is important in mitigating (re-)exposures. Role of antibody maturation, the process whereby selection of higher affinity antibodies augments host immunity, to determine SARS-CoV-2 neutralizing capacity was investigated. METHODS: Sera from SARS-CoV-2 convalescents at 2, 6, or 10 months postrecovery, and BNT162b2 vaccine recipients at 3 or 25 weeks postvaccination, were analyzed. Anti-spike IgG avidity was measured in urea-treated ELISAs. Neutralizing capacity was assessed by surrogate neutralization assays. Fold change between variant and wild-type neutralization inferred the breadth of neutralizing capacity. RESULTS: Compared with early-convalescent, avidity indices of late-convalescent sera were significantly higher (median, 37.7 [interquartile range 28.4-45.1] vs 64.9 [57.5-71.5], P < .0001). Urea-resistant, high-avidity IgG best predicted neutralizing capacity (Spearman r = 0.49 vs 0.67 [wild-type]; 0.18-0.52 vs 0.48-0.83 [variants]). Higher-avidity convalescent sera better cross-neutralized SARS-CoV-2 variants (P < .001 [Alpha]; P < .01 [Delta and Omicron]). Vaccinees only experienced meaningful avidity maturation following the booster dose, exhibiting rather limited cross-neutralizing capacity at week 25. CONCLUSIONS: Avidity maturation was progressive beyond acute recovery from infection, or became apparent after the booster vaccine dose, granting broader anti-SARS-CoV-2 neutralizing capacity. Understanding the maturation kinetics of the 2 building blocks of anti-SARS-CoV-2 humoral immunity is crucial.


Assuntos
Vacina BNT162 , COVID-19 , Humanos , Afinidade de Anticorpos , Soroterapia para COVID-19 , SARS-CoV-2 , Ureia , Vacinação , Imunoglobulina G , Anticorpos Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
18.
Ann Surg ; 277(1): e235-e244, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171860

RESUMO

OBJECTIVE: We aimed to assess whether native spleen preservation during visceral transplantation (VT) affects graft-versus-host-disease (GVHD) incidence. SUMMARY BACKGROUND DATA: GVHD is one of the most severe and frequently lethal hematological complications after VT procedures. Because there is no specific treatment for GVHD, it is imperative to develop a strategy to reduce donor lymphocyte engraftment and proliferation. METHODS: Our study included both clinical and experimental data. A total of 108 patients were divided into 3 groups: a native spleen preservation group, a native spleen removal with no donor spleen group, and a donor spleen included (allogeneic spleen) group. We also used an allogeneic VT rat model, in which recipients were divided into 2 groups: a native spleen preservation (+SP) group and a native spleen removal (-S) group. Skin rash appearance, histopathological changes, chimerism, and spleen effects on circulating allogeneic T-cells were assessed. RESULTS: The patients with native spleen preservation showed a lower rate of GVHD ( P <.001) and better survival ( P <.05) than those in the other groups. Skin and histological signs of GVHD were lower in the rats in the +SP group ( P <.05). The donor T-cell frequency in the bloodstream and skin was also significantly reduced when the native spleen was preserved ( P <.01 and P <.0001, respectively). CONCLUSIONS: The clinical and experimental data indicate that recipient spleen preservation protects against GVHD after VT, and donor cell clearance from the bloodstream by spleen macrophages could be the underlying mechanism. Therefore, spleen preservation should be considered in VT procedures, whenever possible.


Assuntos
Transplante de Medula Óssea , Doença Enxerto-Hospedeiro , Ratos , Animais , Camundongos , Baço , Transplante Homólogo , Linfócitos T , Camundongos Endogâmicos C57BL
19.
J Clin Immunol ; 43(2): 271-285, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36251205

RESUMO

Patients with inborn errors of immunity (IEI) in Argentina were encouraged to receive licensed Sputnik, AstraZeneca, Sinopharm, Moderna, and Pfizer vaccines, even though most of the data of humoral and cellular responses combination on available vaccines comes from trials conducted in healthy individuals. We aimed to evaluate the safety and immunogenicity of the different vaccines in IEI patients in Argentina. The study cohort included adults and pediatric IEI patients (n = 118) and age-matched healthy controls (HC) (n = 37). B cell response was evaluated by measuring IgG anti-spike/receptor binding domain (S/RBD) and anti-nucleocapsid(N) antibodies by ELISA. Neutralization antibodies were also assessed with an alpha-S protein-expressing pseudo-virus assay. The T cell response was analyzed by IFN-γ secretion on S- or N-stimulated PBMC by ELISPOT and the frequency of S-specific circulating T follicular-helper cells (TFH) was evaluated by flow cytometry.No moderate/severe vaccine-associated adverse events were observed. Anti-S/RBD titers showed significant differences in both pediatric and adult IEI patients versus the age-matched HC cohort (p < 0.05). Neutralizing antibodies were also significantly lower in the patient cohort than in age-matched HC (p < 0.01). Positive S-specific IFN-γ response was observed in 84.5% of IEI patients and 82.1% presented S-specific TFH cells. Moderna vaccines, which were mainly administered in the pediatric population, elicited a stronger humoral response in IEI patients, both in antibody titer and neutralization capacity, but the cellular immune response was similar between vaccine platforms. No difference in humoral response was observed between vaccinated patients with and without previous SARS-CoV-2 infection.In conclusion, COVID-19 vaccines showed safety in IEI patients and, although immunogenicity was lower than HC, they showed specific anti-S/RBD IgG, neutralizing antibody titers, and T cell-dependent cellular immunity with IFN-γ secreting cells. These findings may guide the recommendation for a vaccination with all the available vaccines in IEI patients to prevent COVID-19 disease.


Assuntos
COVID-19 , Vacinas , Adulto , Humanos , Criança , Vacinas contra COVID-19 , Leucócitos Mononucleares , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Anticorpos Neutralizantes , ELISPOT , Imunoglobulina G , Anticorpos Antivirais , Imunidade Celular
20.
Epilepsia ; 64(7): e148-e155, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37203213

RESUMO

Variable phenotypes, including developmental encephalopathy with (DEE) or without seizures and myoclonic epilepsy and ataxia due to potassium channel mutation, are caused by pathogenetic variants in KCNC1, encoding for Kv3.1 channel subunits. In vitro, channels carrying most KCNC1 pathogenic variants display loss-of-function features. Here, we describe a child affected by DEE with fever-triggered seizures, caused by a novel de novo heterozygous missense KCNC1 variant (c.1273G>A; V425M). Patch-clamp recordings in transiently transfected CHO cells revealed that, compared to wild-type, Kv3.1 V425M currents (1) were larger, with membrane potentials between -40 and +40 mV; (2) displayed a hyperpolarizing shift in activation gating; (3) failed to inactivate; and (4) had slower activation and deactivation kinetics, consistent with a mixed functional pattern with prevalent gain-of-function effects. Exposure to the antidepressant drug fluoxetine inhibited currents expressed by both wild-type and mutant Kv3.1 channels. Treatment of the proband with fluoxetine led to a rapid and prolonged clinical amelioration, with the disappearance of seizures and an improvement in balance, gross motor skills, and oculomotor coordination. These results suggest that drug repurposing based on the specific genetic defect may provide an effective personalized treatment for KCNC1-related DEEs.


Assuntos
Epilepsias Mioclônicas , Convulsões Febris , Cricetinae , Animais , Fluoxetina/uso terapêutico , Cricetulus , Medicina de Precisão , Mutação com Ganho de Função , Convulsões/genética , Epilepsias Mioclônicas/tratamento farmacológico , Epilepsias Mioclônicas/genética
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