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1.
FASEB J ; 38(4): e23486, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38407497

RESUMO

Sperm capacitation is a critical process for male fertility. It involves a series of biochemical and physiological changes that occur in the female reproductive tract, rendering the sperm competent for successful fertilization. The precise mechanisms and, specifically, the role of mitochondria, in sperm capacitation remain incompletely understood. Previously, we revealed that in mouse sperm mitochondrial activity (e.g., oxygen consumption, membrane potential, ATP/ADP exchange, and mitochondrial Ca2+ ) increases during capacitation. Herein, we studied mitochondrial function by high-resolution respirometry (HRR) and reactive oxygen species production in capacitated (CAP) and non-capacitated (NC) human spermatozoa. We found that in capacitated sperm from normozoospermic donors, the respiratory control ratio increased by 36%, accompanied by a double oxygen consumption rate (OCR) in the presence of antimycin A. Extracellular hydrogen peroxide (H2 O2 ) detection was three times higher in CAP than in NC sperm cells. To confirm that H2 O2 production depends on mitochondrial superoxide ( O 2 · - $$ {\mathrm{O}}_2^{\cdotp -} $$ ) formation, we evaluated mitochondrial aconitase (ACO2) amount, activity, and role in the metabolic flux from the sperm tricarboxylic acid cycle. We estimated that CAP cells produce, on average by individual, (59 ± 22)% more O 2 · - $$ {\mathrm{O}}_2^{\cdotp -} $$ in the steady-state compared to NC cells. Finally, we analyzed two targets of oxidative stress: lipid peroxidation by western blot against 4-hydroxynonenal and succinate dehydrogenase (SDH) activity by HRR. We did not observe modifications in lipoperoxidation nor the activity of SDH, suggesting that during capacitation, the increase in mitochondrial H2 O2 production does not damage sperm and it is necessary for the normal CAP process.


Assuntos
Mitocôndrias , Sêmen , Humanos , Masculino , Feminino , Animais , Camundongos , Espécies Reativas de Oxigênio , Espermatozoides , Superóxidos
2.
Proc Natl Acad Sci U S A ; 119(47): e2213432119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36378644

RESUMO

Cytochrome c (cyt c) can undergo reversible conformational changes under biologically relevant conditions. Revealing these alternative cyt c conformers at the cell and tissue level is challenging. A monoclonal antibody (mAb) identifying a key conformational change in cyt c was previously reported, but the hybridoma was rendered nonviable. To resurrect the mAb in a recombinant form, the amino-acid sequences of the heavy and light chains were determined by peptide mapping-mass spectrometry-bioinformatic analysis and used to construct plasmids encoding the full-length chains. The recombinant mAb (R1D3) was shown to perform similarly to the original mAb in antigen-binding assays. The mAb bound to a variety of oxidatively modified cyt c species (e.g., nitrated at Tyr74 or oxidized at Met80), which lose the sixth heme ligation (Fe-Met80); it did not bind to several cyt c phospho- and acetyl-mimetics. Peptide competition assays together with molecular dynamic studies support that R1D3 binds a neoepitope within the loop 40-57. R1D3 was employed to identify alternative conformations of cyt c in cells under oxidant- or senescence-induced challenge as confirmed by immunocytochemistry and immunoaffinity studies. Alternative conformers translocated to the nuclei without causing apoptosis, an observation that was further confirmed after pinocytic loading of oxidatively modified cyt c to B16-F1 cells. Thus, alternative cyt c conformers, known to gain peroxidatic function, may represent redox messengers at the cell nuclei. The availability and properties of R1D3 open avenues of interrogation regarding the presence and biological functions of alternative conformations of cyt c in mammalian cells and tissues.


Assuntos
Citocromos c , Heme , Animais , Sequência de Aminoácidos , Anticorpos Monoclonais , Citocromos c/química , Heme/química , Hibridomas , Oxirredução , Melanoma Experimental , Camundongos
3.
Am Heart J ; 273: 148-158, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38679190

RESUMO

BACKGROUND: Advances in managing adult congenital heart disease (ACHD) have led to an increased number of women with CHD reaching childbearing age. This demographic shift underscores the need for improved understanding and prediction of complications during pregnancy in this specific ACHD population. Despite progress in maternal cardiac risk assessment, the prediction of neonatal outcomes for ACHD pregnancies remains underdeveloped. Therefore, the aims of this study are to assess neonatal outcomes in a CHD women population, to identify their predictive factors and to propose a new risk score for predicting neonatal complications. METHODS: This registry study included all women born between 1975 and 1996 diagnosed with ACHD who underwent at least one cardiology consultation for ACHD in Cliniques Universitaires Saint-Luc. A multivariate analysis was performed to identify predictors of neonatal complications and these were incorporated into a new risk index. Its validity was assessed using bootstrap method. This score was then compared with scores adapted from the ZAHARA and CARPREG studies for offspring events prediction. RESULTS: Analysis of 491 pregnancies revealed 31.4% of neonatal complications. Four significant predictors of adverse neonatal outcomes were identified: cardiac treatment during pregnancy (OR 14.8, 95%CI [3.4-66]), hypertensive disorders of pregnancy (OR 11.4, 95%CI [3.4-39.0]), smoking during pregnancy (OR 10.6, 95%CI [2.8-40.6]), and pre-pregnancy BMI <18.5 kg/m² (OR 6.5, 95%CI [2.5-16.5]). The risk model demonstrated an AUC of 0.70 (95%CI [0.65-0.75]), which remained stable after bootstrap validation. This model significantly outperformed the scores adapted from ZAHARA and CARPREG data. Based on the regression coefficients, a risk score was subsequently developed comprising five risk categories. CONCLUSIONS: One third of ACHD pregnancies are complicated by poor neonatal outcome. These complications are determined by four independent factors relating to the cardiac and non-cardiac status of the patients, which have been incorporated into a risk score. Our study is one of the first to propose a predictive risk score of neonatal outcomes in ACHD pregancies, and paves the way for other validation and confirmation studies.


Assuntos
Cardiopatias Congênitas , Complicações Cardiovasculares na Gravidez , Resultado da Gravidez , Humanos , Feminino , Gravidez , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/diagnóstico , Recém-Nascido , Adulto , Medição de Risco/métodos , Complicações Cardiovasculares na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Fatores de Risco , Sistema de Registros , Estudos Retrospectivos
4.
Hum Genomics ; 17(1): 14, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849973

RESUMO

The SPATA5 gene encodes a 892 amino-acids long protein that has a putative mitochondrial targeting sequence and has been proposed to function in maintenance of mitochondrial function and integrity during mouse spermatogenesis. Several studies have associated homozygous or compound heterozygous mutations in SPATA5 gene to microcephaly, intellectual disability, seizures and hearing loss. This suggests a role of the SPATA5 gene also in neuronal development. Recently, our group presented results validating the use of blood cells for the assessment of mitochondrial function for diagnosis and follow-up of mitochondrial disease, minimizing the need for invasive procedures such as muscle biopsy. In this study, we were able to diagnose a patient with epileptogenic encephalopathy using next generation sequencing. We found two novel compound heterozygous variants in SPATA5 that are most likely causative. To analyze the impact of SPATA5 mutations on mitochondrial functional studies directly on the patients' mononuclear cells and platelets were undertaken. Oxygen consumption rates in platelets and PBMCs were impaired in the patient when compared to a healthy control. Also, a decrease in mitochondrial mass was observed in the patient monocytes with respect to the control. This suggests a true pathogenic effect of the mutations in mitochondrial function, especially in energy production and possibly biogenesis, leading to the observed phenotype.


Assuntos
Encefalopatias , Microcefalia , Animais , Masculino , Camundongos , Biópsia , Mitocôndrias/genética , Convulsões , ATPases Associadas a Diversas Atividades Celulares/metabolismo
5.
Biol Res ; 57(1): 12, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561836

RESUMO

BACKGROUND: Bacterial aromatic degradation may cause oxidative stress. The long-chain flavodoxin FldX1 of Paraburkholderia xenovorans LB400 counteracts reactive oxygen species (ROS). The aim of this study was to evaluate the protective role of FldX1 in P. xenovorans LB400 during the degradation of 4-hydroxyphenylacetate (4-HPA) and 3-hydroxyphenylacetate (3-HPA). METHODS: The functionality of FldX1 was evaluated in P. xenovorans p2-fldX1 that overexpresses FldX1. The effects of FldX1 on P. xenovorans were studied measuring growth on hydroxyphenylacetates, degradation of 4-HPA and 3-HPA, and ROS formation. The effects of hydroxyphenylacetates (HPAs) on the proteome (LC-MS/MS) and gene expression (qRT-PCR) were quantified. Bioaugmentation with strain p2-fldX1 of 4-HPA-polluted soil was assessed, measuring aromatic degradation (HPLC), 4-HPA-degrading bacteria, and plasmid stability. RESULTS: The exposure of P. xenovorans to 4-HPA increased the formation of ROS compared to 3-HPA or glucose. P. xenovorans p2-fldX1 showed an increased growth on 4-HPA and 3-HPA compared to the control strain WT-p2. Strain p2-fldX1 degraded faster 4-HPA and 3-HPA than strain WT-p2. Both WT-p2 and p2-fldX1 cells grown on 4-HPA displayed more changes in the proteome than cells grown on 3-HPA in comparison to glucose-grown cells. Several enzymes involved in ROS detoxification, including AhpC2, AhpF, AhpD3, KatA, Bcp, CpoF1, Prx1 and Prx2, were upregulated by hydroxyphenylacetates. Downregulation of organic hydroperoxide resistance (Ohr) and DpsA proteins was observed. A downregulation of the genes encoding scavenging enzymes (katE and sodB), and gstA and trxB was observed in p2-fldX1 cells, suggesting that FldX1 prevents the antioxidant response. More than 20 membrane proteins, including porins and transporters, showed changes in expression during the growth of both strains on hydroxyphenylacetates. An increased 4-HPA degradation by recombinant strain p2-fldX1 in soil microcosms was observed. In soil, the strain overexpressing the flavodoxin FldX1 showed a lower plasmid loss, compared to WT-p2 strain, suggesting that FldX1 contributes to bacterial fitness. Overall, these results suggest that recombinant strain p2-fldX1 is an attractive bacterium for its application in bioremediation processes of aromatic compounds. CONCLUSIONS: The long-chain flavodoxin FldX1 improved the capability of P. xenovorans to degrade 4-HPA in liquid culture and soil microcosms by protecting cells against the degradation-associated oxidative stress.


Assuntos
Burkholderia , Burkholderiaceae , Flavodoxina , Gliceraldeído/análogos & derivados , Fenilacetatos , Propano , Biodegradação Ambiental , Flavodoxina/metabolismo , Flavodoxina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteoma/metabolismo , Proteoma/farmacologia , Cromatografia Líquida , Burkholderia/genética , Burkholderia/metabolismo , Espectrometria de Massas em Tandem , Estresse Oxidativo , Glucose/metabolismo , Solo
6.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893343

RESUMO

Polyphenols are plant secondary metabolites that function mostly as a general stress-induced protective mechanism. Polyphenols have also gained interest due to their beneficial properties for human health. Strawberry leaves represent an agro-industrial waste material with relevant bioactive polyphenol content, which could be incorporated into circular economy strategies. However, due to the low quantities of polyphenols in plants, their production needs to be improved for cost-effective applications. The objective of this research was to compare polyphenol production in strawberry (Fragaria × ananassa cv. Festival) leaves in plants grown in greenhouse conditions and plants grown in vitro, using three possible elicitor treatments (UV irradiation, cold exposure, and cysteine). General vegetative effects were morphologically evaluated, and specific polyphenolic compounds were quantified by UHPLC-DAD-MS/MS. Gallic acid was the most abundant polyphenol found in the leaves, both in vivo and in vitro. The results showed higher amounts and faster accumulation of polyphenols in the in vitro regenerated plants, highlighting the relevance of in vitro tissue culture strategies for producing compounds such as polyphenols in this species and cultivar.


Assuntos
Fragaria , Folhas de Planta , Polifenóis , Fragaria/química , Fragaria/metabolismo , Polifenóis/química , Folhas de Planta/química , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Ácido Gálico/química
7.
Molecules ; 28(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838852

RESUMO

Berry fruits are an important dietary source of health-promoting antioxidant polyphenols. Interestingly, berry leaves of diverse species, including strawberries, have shown higher bioactive phytochemical content in the leaves than in the fruit. Moreover, the vegetative part of the plants is usually discarded, representing a presumably large source of underutilized bioactive biomass. In this investigation, the polyphenol profiles of tropical highland strawberry (Fragaria x ananassa cv. Festival) leaves and fruits were compared by high-performance liquid chromatography coupled with a diode array detector (UHPLC-DAD) and mass spectrometry (HPLC-MS). The total polyphenol strawberry leaf extracts exhibited a 122-fold-higher total polyphenol content and 13-fold higher antioxidant activity (ORAC) than strawberry fruits, and they showed evidence of possible photoprotective effects against UV damage in human melanoma cells (SK-MEL-28) and in murine embryo fibroblasts (NIH/3T3), together with promising anti-proliferative activities against the same melanoma cells. Seven polyphenols were confirmed by HPLC-DAD in the leaf extracts, with differences depending on fraction solubility. Moreover, three substituted quercetin derivatives, three substituted kaempferol derivatives, two anthocyanins, and catechin were confirmed in the soluble fraction by HPLC-MS. Given their higher total polyphenol content and bioactive activities, underutilized strawberry Festival leaves are a potential source of apparently abundant biomass with prospective bioactive applications.


Assuntos
Fragaria , Polifenóis , Animais , Humanos , Camundongos , Polifenóis/análise , Fragaria/química , Frutas/química , Antocianinas/química , Férias e Feriados , Estudos Prospectivos , Antioxidantes/química , Compostos Fitoquímicos/análise
8.
Molecules ; 28(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36770962

RESUMO

Micellar microemulsions are thermodynamically stable self-emulsifying systems that have been used to successfully improve the low oral bioavailability of several bioactive phytochemicals, such as antioxidant polyphenols. However, most studies have reported the micellization of single-compounds or purified chemical fractions; thus, the stability, phytochemical-loading efficiency, and bioactivity of complex crude extracts remain largely unexplored. In this study, we evaluated the effects of micellar emulsification of tropical apple (Malus domestica cv. Anna), plum (Prunus domestica cv. Satsuma), and guava (Psidium guajava L.) extracts regarding particle size and stability, polyphenol-loading efficiency, antioxidant capacity, and cytotoxic activity in human and murine cells. Simple food-grade extraction protocols were implemented to obtain apple, plum, and guava extracts. Total polyphenols, flavonoids, and antioxidant activity (DPPH) were determined in the fruit extracts, and their polyphenol profile was further characterized by liquid chromatography (HPLC-DAD). The dried extracts were mixed into a food-grade, self-emulsifying system, and their cytotoxicity in human and murine cell lines was compared. Our research showed that complex fruit matrixes were successfully emulsified into thermodynamically stable polysorbate-based nanometric micelles with uniform size distribution and consistent pH stability, with potential applications in food and biomedical industries.


Assuntos
Malus , Prunus domestica , Psidium , Humanos , Animais , Camundongos , Frutas/química , Antioxidantes/química , Psidium/química , Polifenóis/farmacologia , Polifenóis/análise , Extratos Vegetais/química
9.
Curr Ther Res Clin Exp ; 98: 100696, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950457

RESUMO

Background: Sickle cell disease (SCD) is an inherited, chronic, multifaceted blood disorder. Patients with SCD develop anemia, which has been associated with end-organ damage (EOD). Objectives: This retrospective, observational, repeated-measures study systematically characterizes the relationship between hemoglobin (Hb) level and EOD in adolescent and adult patients with SCD. Methods: The study population comprised patients with SCD aged ≥12 years with available Hb data from a US provider-centric health care database. For each patient, each Hb value over time was included as a separate observation. Study outcomes-the onset of any new EOD, including chronic kidney disease, pulmonary hypertension, stroke, and leg ulcer-were ascertained during the 1-year period after each Hb assessment. The association between Hb levels and risk of new EOD was estimated using multivariable generalized estimating equations. Results: A total of 16,043 unique patients with SCD contributed 44,913 observations. Adjusted odds of any EOD during the 1-year follow-up were significantly lower with higher Hb level. Risk reductions with higher Hb levels for chronic kidney disease, pulmonary hypertension, and leg ulcer were comparable. The risk of new EOD was significantly lower among adolescent and adult patients with higher Hb levels. Conclusions: In patients with SCD, higher Hb levels are associated with a reduced risk of developing EOD. Therapeutic strategies that result in higher Hb levels may offer clinical and economic value for patients with SCD. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX).

10.
Circulation ; 143(24): 2395-2405, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34125564

RESUMO

In the United States, race-based disparities in cardiovascular disease care have proven to be pervasive, deadly, and expensive. African American/Black, Hispanic/Latinx, and Native/Indigenous American individuals are at an increased risk of cardiovascular disease and are less likely to receive high-quality, evidence-based medical care as compared with their White American counterparts. Although the United States population is diverse, the cardiovascular workforce that provides its much-needed care lacks diversity. The available data show that care provided by physicians from racially diverse backgrounds is associated with better quality, both for minoritized patients and for majority patients. Not only is cardiovascular workforce diversity associated with improvements in health care quality, but racial diversity among academic teams and research scientists is linked with research quality. We outline documented barriers to achieving workforce diversity and suggest evidence-based strategies to overcome these barriers. Key strategies to enhance racial diversity in cardiology include improving recruitment and retention of racially diverse members of the cardiology workforce and focusing on cardiovascular health equity for patients. This review draws attention to academic institutions, but the implications should be considered relevant for nonacademic and community settings as well.


Assuntos
Cardiologistas/estatística & dados numéricos , Feminino , Equidade em Saúde , Humanos , Masculino , Grupos Raciais , Estados Unidos , Recursos Humanos
11.
Br J Haematol ; 196(4): 1059-1068, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859423

RESUMO

Our aim was to determine differences in the prevalence of mental health disorders between Black Americans living with sickle cell disease (SCD) and Black Americans with other, non-heritable medical conditions, or no medical conditions. We examined the prevalence of mental health disorders among a non-institutionalized, community sample of Black adults in the US from the National Survey of American Life. We compared the odds of mental health disorders between Black American adults with SCD and those with other medical conditions, or no medical condition. Among the SCD group, 38·8% reported at least one mental health disorder: 17·6% endorsed a mood disorder, 24·7% an anxiety disorder, 2·4% an eating disorder, and 11·8% a childhood disorder. Compared to those with other medical conditions, Black Americans with SCD had greater poverty, more children in the household, and were less likely to be married/cohabitating (all P < 0·05). Yet, Black Americans with SCD were not at greater odds of having a mental health disorder compared to those with other medical conditions. When compared to the group with no conditions, however, individuals with SCD had 2·57 greater odds of mood disorder (95% confidence interval: 1·43-4·65; P = 0·002). The effect remained when controlling for socioeconomic status, marital status, and perceived physical health. In this study, almost 40% of Black American adults with SCD presented with a mental health disorder. Prevalence of mental health disorders was similar among those with non-heritable medical conditions, but those without a medical condition had a lower prevalence than in SCD. Among Black Americans, there appear to be unmeasured factors, common across medical conditions, that are linked to mental health disorders.


Assuntos
Anemia Falciforme/psicologia , Transtornos Mentais/psicologia , Adulto , Negro ou Afro-Americano , Estudos Transversais , Feminino , Humanos , Masculino , Saúde Mental , Prevalência
12.
Biol Res ; 55(1): 7, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35184754

RESUMO

BACKGROUND: Aerobic metabolism generates reactive oxygen species that may cause critical harm to the cell. The aim of this study is the characterization of the stress responses in the model aromatic-degrading bacterium Paraburkholderia xenovorans LB400 to the oxidizing agents paraquat and H2O2. METHODS: Antioxidant genes were identified by bioinformatic methods in the genome of P. xenovorans LB400, and the phylogeny of its OxyR and SoxR transcriptional regulators were studied. Functionality of the transcriptional regulators from strain LB400 was assessed by complementation with LB400 SoxR of null mutant P. aeruginosa ΔsoxR, and the construction of P. xenovorans pIZoxyR that overexpresses OxyR. The effects of oxidizing agents on P. xenovorans were studied measuring bacterial susceptibility, survival and ROS formation after exposure to paraquat and H2O2. The effects of these oxidants on gene expression (qRT-PCR) and the proteome (LC-MS/MS) were quantified. RESULTS: P. xenovorans LB400 possesses a wide repertoire of genes for the antioxidant defense including the oxyR, ahpC, ahpF, kat, trxB, dpsA and gorA genes, whose orthologous genes are regulated by the transcriptional regulator OxyR in E. coli. The LB400 genome also harbors the soxR, fumC, acnA, sodB, fpr and fldX genes, whose orthologous genes are regulated by the transcriptional regulator SoxR in E. coli. The functionality of the LB400 soxR gene was confirmed by complementation of null mutant P. aeruginosa ΔsoxR. Growth, susceptibility, and ROS formation assays revealed that LB400 cells were more susceptible to paraquat than H2O2. Transcriptional analyses indicated the upregulation of the oxyR, ahpC1, katE and ohrB genes in LB400 cells after exposure to H2O2, whereas the oxyR, fumC, ahpC1, sodB1 and ohrB genes were induced in presence of paraquat. Proteome analysis revealed that paraquat induced the oxidative stress response proteins AhpCF and DpsA, the universal stress protein UspA and the RNA chaperone CspA. Both oxidizing agents induced the Ohr protein, which is involved in organic peroxide resistance. Notably, the overexpression of the LB400 oxyR gene in P. xenovorans significantly decreased the ROS formation and the susceptibility to paraquat, suggesting a broad OxyR-regulated antioxidant response. CONCLUSIONS: This study showed that P. xenovorans LB400 possess a broad range oxidative stress response, which explain the high resistance of this strain to the oxidizing compounds paraquat and H2O2.


Assuntos
Proteínas de Escherichia coli , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Burkholderiaceae , Cromatografia Líquida , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Peróxido de Hidrogênio/farmacologia , Oxirredução , Estresse Oxidativo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Espectrometria de Massas em Tandem
13.
Int J Mol Sci ; 22(23)2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34884666

RESUMO

Congenital long QT syndrome (LQTS) is a cardiac channelopathy characterized by a prolongation of the QT interval and T-wave abnormalities, caused, in most cases, by mutations in KCNQ1, KCNH2, and SCN5A. Although the predominant pattern of LQTS inheritance is autosomal dominant, compound heterozygous mutations in genes encoding potassium channels have been reported, often with early disease onset and more severe phenotypes. Since the molecular mechanisms underlying severe phenotypes in carriers of compound heterozygous mutations are unknown, it is possible that these compound mutations lead to synergistic or additive alterations to channel structure and function. In this study, all-atom molecular dynamic simulations of KCNQ1 and hERG channels were carried out, including wild-type and channels with compound mutations found in two patients with severe LQTS phenotypes and limited family history of the disease. Because channels can likely incorporate different subunit combinations from different alleles, there are multiple possible configurations of ion channels in LQTS patients. This analysis allowed us to establish the structural impact of different configurations of mutant channels in the activated/open state. Our data suggest that channels with these mutations show moderate changes in folding energy (in most cases of stabilizing character) and changes in channel mobility and volume, differentiating them from each other and from WT. This would indicate possible alterations in K+ ion flow. Hetero-tetrameric mutant channels showed intermediate structural and volume alterations vis-à-vis homo-tetrameric channels. These findings support the hypothesis that hetero-tetrameric channels in patients with compound heterozygous mutations do not necessarily lead to synergistic structural alterations.


Assuntos
Canalopatias/genética , Canal de Potássio ERG1/metabolismo , Canal de Potássio KCNQ1/metabolismo , Síndrome do QT Longo/genética , Simulação de Dinâmica Molecular , Criança , Pré-Escolar , Canal de Potássio ERG1/genética , Humanos , Canal de Potássio KCNQ1/genética , Masculino
14.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684778

RESUMO

Biohydrometallurgy recovers metals through microbially mediated processes and has been traditionally applied for the extraction of base metals from low-grade sulfidic ores. New investigations explore its potential for other types of critical resources, such as rare earth elements. In recent times, the interest in rare earth elements (REEs) is growing due to of their applications in novel technologies and green economy. The use of biohydrometallurgy for extracting resources from waste streams is also gaining attention to support innovative mining and promote a circular economy. The increase in wastes containing REEs turns them into a valuable alternative source. Most REE ores and industrial residues do not contain sulfides, and bioleaching processes use autotrophic or heterotrophic microorganisms to generate acids that dissolve the metals. This review gathers information towards the recycling of REE-bearing wastes (fluorescent lamp powder, spent cracking catalysts, e-wastes, etc.) using a more sustainable and environmentally friendly technology that reduces the impact on the environment.


Assuntos
Resíduos Industriais/análise , Metalurgia/métodos , Metais Terras Raras/isolamento & purificação , Microbiologia Industrial/métodos , Mineração , Reciclagem/métodos
15.
J Relig Health ; 60(5): 3576-3590, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33710465

RESUMO

Religious and spiritual (R/S) issues impact medical decision-making, particularly among highly R/S populations, for whom existing measures have limitations in identifying levels of R/S commitment. The Belief into Action (BIAc) scale was designed for this purpose and was never tested among hospitalized patients. We interviewed 152 patients (51% men) with a mean age of 48.9 years (SD = 15.2), having either cancer (27%), cardiovascular (26%), rheumatic (21%), or other diseases (26%). Cronbach alpha was .82 and a 3-factor structure (subjective, social, and private religious commitment) was the most robust. Results suggest the BIAc has adequate convergent, divergent, and incremental validity compared to other well-established questionnaires and is appropriate for the inpatient setting.


Assuntos
Pacientes Internados , Neoplasias , Diversidade Cultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
16.
Acc Chem Res ; 52(9): 2609-2619, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31287291

RESUMO

Mammalian aconitases (mitochondrial and cytosolic isoenzymes) are unique iron-sulfur cluster-containing proteins in which the metallic center participates in the catalysis of a non-redox reaction. Within the cubane iron-sulfur cluster of aconitases only three of the four iron ions have cysteine thiolate ligands; the fourth iron ion (Feα) is solvent exposed within the active-site pocket and bound to oxygen atoms from either water or substrates to be dehydrated. The catalyzed reaction is the reversible isomerization of citrate to isocitrate with an intermediate metabolite, cis-aconitate. The cytosolic isoform of aconitase is a moonlighting enzyme; when intracellular iron is scarce, the complete disassembly of the iron-sulfur cluster occurs and apo-aconitase acquires the function of an iron responsive protein and regulates the translation of proteins involved in iron metabolism. In the late 1980s and during the 1990s, cumulative experimental evidence pointed out that aconitases are main targets of reactive oxygen and nitrogen species such as superoxide radical (O2•-), hydrogen peroxide (H2O2), nitric oxide (•NO), and peroxynitrite (ONOO-). These intermediates are capable of oxidizing the cluster, which leads to iron release and consequent loss of the catalytic activity of aconitase. As the reaction of the Fe-S cluster with O2•- is fast (∼107 M-1 s-1), quite specific, and reversible in vivo, quantification of active aconitase has been used to evaluate O2•- formation in cells. While •NO is modestly reactive with aconitase, its reaction with O2•- yields ONOO-, a strong oxidant that readily leads to the disruption of the Fe-S cluster. In the case of cytosolic aconitase, it has been seen that H2O2 and •NO promote activation of iron responsive protein activity in cells. Proteomic advances in the 2000s confirmed that aconitases are main targets of reactive species in cellular models and in vivo, and other post-translational oxidative modifications such as protein nitration and carbonylation have been detected. Herein, we (1) outline the particular structural features of aconitase that make these proteins specific targets of reactive species, (2) characterize the reactions of O2•-, H2O2, •NO, and ONOO- and related species with aconitases, (3) discuss how different oxidative post-translational modifications of aconitase impact the different functions of aconitases, and (4) argue how these proteins might function as redox sensors within different cellular compartments, regulating citrate concentration and efflux from mitochondria, iron availability in the cytosol, and cellular oxidant production.


Assuntos
Aconitato Hidratase/metabolismo , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Ácido Peroxinitroso/metabolismo , Superóxidos/metabolismo , Aconitato Hidratase/química , Animais , Humanos , Peróxido de Hidrogênio/química , Mitocôndrias/enzimologia , Modelos Moleculares , Óxido Nítrico/química , Ácido Peroxinitroso/química , Superóxidos/química
17.
Sleep Breath ; 24(4): 1357-1363, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31792908

RESUMO

PURPOSE: The negative association between obstructive sleep apnea (OSA) and adverse cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) is well documented. However, little is known about the influence of OSA on fibrinolytic therapy. The aim of this study was to evaluate the impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction (STEMI) patients. METHODS: We enrolled consecutive STEMI patients without previous vascular disease, heart failure, or OSA diagnosis. All patients underwent either a pharmacoinvasive therapy or primary PCI. Syntax score (SS) was calculated for all patients, and a full bedside polysomnography was performed in the first 72 h of admission. In-hospital events and 30 days readmissions were analyzed. RESULTS: The sample included 116 patients, 87 men. Patients with severe OSA were older (p = 0.01), had higher neck and abdominal circumferences (p < 0.01), and had higher BMI (p < 0.01). They also had lower reperfusion rates post-fibrinolysis (20 vs. 65%; p = 0.001), higher SS (20.2 ± 11.2 vs. 14.6 ± 10.6; p = 0.03), lower left ventricle ejection fraction (45 ± 8 vs. 51 ± 10%; p = 0.02), and a higher incidence of atrial arrhythmias (4 vs. 21%; p = 0.02). STEMI patients with severe OSA presented with threefold increase in the risk for at least one adverse outcome. Regression analysis showed that both severe OSA and hypertension were independent predictors of higher SS. CONCLUSION: Severe OSA was associated with a poor outcome after pharmacoinvasive treatment in STEMI patients.


Assuntos
Fibrinolíticos/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Apneia Obstrutiva do Sono/complicações , Terapia Trombolítica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento
18.
Arch Gynecol Obstet ; 302(3): 753-762, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32712928

RESUMO

PURPOSE: The purpose of this study was to evaluate stiffness changes occurring in the healthy uterine cervix according to age, parity, phase of the menstrual cycle and other factors by shear wave elastography (SWE). METHODS: Evaluations of cervical speed and stiffness measurements were performed in 50 non-pregnant patients without gynaecological pathology using SWE transvaginal ultrasound. We performed the evaluation in the midsagittal plane of the uterine cervix with measurements at 0.5, 1 and 1.5 cm from external cervical os, at both anterior and posterior cervical lips. RESULTS: We evaluated 44 patients by SWE and obtained a total average velocity of 3.48 ± 1.08 m/s and stiffness of 42.39 ± 25.33 kPa. We found differences in speed and stiffness according to the cervical lip and depth evaluated; thus, we observed a velocity of 2.70 m/s at 0.5 cm of depth in the anterior lip and 3.53 m/s at 1.5 cm of depth in the posterior lip (p < 0.05). We observed differences according to parity, obtaining a wave transmission speed of 2.67 m/s and 4.41 m/s at the cervical canal of nulliparous and multiparous patients, respectively (p < 0 0.002). We observed differences according to patient age (from a speed of 2.75 m/s at the cervical canal in the age group of 20-35 years to 5.05 m/s in the age group > 50 years) (p < 0.008). We did not observe differences in speed or stiffness according to the phase of the menstrual cycle, BMI, smoking status or the presence or absence of non-HPV infections. CONCLUSIONS: The wave transmission speed and stiffness of the uterine cervix evaluated by SWE varies according to the cervical lip and depth of the evaluation as well as according to the parity and age of the patient.


Assuntos
Colo do Útero/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Adolescente , Adulto , Idoso , Colo do Útero/fisiopatologia , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
19.
Int J Mol Sci ; 21(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053805

RESUMO

Two series of new hybrid γ/γ-peptides, γ-CC and γ-CT, formed by (1S,2R)-3-amino-2,2,dimethylcyclobutane-1-carboxylic acid joined in alternation to a Nα-functionalized cis- or trans-γ-amino-l-proline derivative, respectively, have been synthesized and evaluated as cell penetrating peptides (CPP) and as selective vectors for anti-Leishmania drug delivery systems (DDS). They lacked cytotoxicity on the tumoral human cell line HeLa with a moderate cell-uptake on these cells. In contrast, both γ-CC and γ-CT tetradecamers were microbicidal on the protozoan parasite Leishmania beyond 25 µM, with significant intracellular accumulation. They were conjugated to fluorescent doxorubicin (Dox) as a standard drug showing toxicity beyond 1 µM, while free Dox was not toxic. Intracellular accumulation was 2.5 higher than with Dox-TAT conjugate (TAT = transactivator of transcription, taken as a standard CPP). The conformational structure of the conjugates was approached both by circular dichroism spectroscopy and molecular dynamics simulations. Altogether, computational calculations predict that the drug-γ-peptide conjugates adopt conformations that bury the Dox moiety into a cavity of the folded peptide, while the positively charged guanidinium groups face the solvent. The favorable charge/hydrophobicity balance in these CPP improves the solubility of Dox in aqueous media, as well as translocation across cell membranes, making them promising candidates for DDS.


Assuntos
Antiprotozoários/química , Antiprotozoários/farmacologia , Peptídeos Penetradores de Células/química , Ciclobutanos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Células HeLa , Humanos , Modelos Moleculares , Estrutura Molecular , Testes de Sensibilidade Parasitária , Análise Espectral , Relação Estrutura-Atividade
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