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1.
Genet Mol Biol ; 47(1): e20230172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578013

RESUMO

We announce the mitochondrial genomes of seven species of the genus Sporophila (S. bouvreuil, S. iberaensis, S. melanogaster, S. minuta, S. nigrorufa, S. pileata, and S. ruficollis) which were validated by comparative genomic and phylogenetic analysis with related species. The mitochondrial genomes of seven passerines of the genus Sporophila were assembled (three complete and four nearly complete genomes) and were validated by reconstructing phylogenetic relations within Thraupidae. The complete mitogenomes ranged from 16,781 bp in S. ruficollis to 16,791 bp in S. minuta. We identified a conserved genome composition within all mitogenomes with 13 protein-coding genes, 22 tRNAs and two rRNAs. We observed a bias in the nucleotide composition and six mutational hotspots in Sporophila mitogenomes. Our mitogenome-based phylogenetic tree has S. minuta, S. maximiliani and S. nigricollis as sister species of the remaining species in the genus. We present new mitogenome sequences for seven Sporophila species, providing new genomic resources that may be useful for research on the evolution, comparative genetics, and conservation of this threatened group.

2.
Scand J Immunol ; 98(3): e13257, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37873571

RESUMO

Adiponectin and leptin are adipokines, secreted by white adipose tissue (WAT), which play an important role in energy homeostasis. Some evidence has shown that adipokine-producing adipose cells present in the bone marrow (BM) appear to exert an influence on hematopoiesis and B cell development. Common variable immunodeficiency (CVID) is one of the most common inborn errors of immunity in humans. In CVID, numerical and/or functional defects of B cells and their precursors result in hypogammaglobulinemia, usually Immunoglobulin (Ig) A and IgG. Manifestations of CVID include immunodeficiency, autoimmunity, inflammation and lymphoproliferation, resulting in a wide range of phenotypes. How adipokines interact and influence the pathophysiology of CVID is still unclear. In this review, we seek to summarize the aspects known so far concerning the interface between adipokines, B cells and CVID. More research is needed to fully understand these interactions; this knowledge is a potential avenue for the discovery of useful biomarkers and may provide new therapeutic targets for the treatment of patients with CVID and related diseases.


Assuntos
Adipocinas , Imunodeficiência de Variável Comum , Humanos , Linfócitos B , Autoimunidade , Imunoglobulina A , Tecido Adiposo
3.
J Immunol ; 207(2): 626-639, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34261666

RESUMO

Sepsis is a complex infectious syndrome in which neutrophil participation is crucial for patient survival. Neutrophils quickly sense and eliminate the pathogen by using different effector mechanisms controlled by metabolic processes. The mammalian target of rapamycin (mTOR) pathway is an important route for metabolic regulation, and its role in neutrophil metabolism has not been fully understood yet, especially the importance of mTOR complex 2 (mTORC2) in the neutrophil effector functions. In this study, we observed that the loss of Rictor (mTORC2 scaffold protein) in primary mouse-derived neutrophils affects their chemotaxis by fMLF and their microbial killing capacity, but not the phagocytic capacity. We found that the microbicidal capacity was impaired in Rictor-deleted neutrophils because of an improper fusion of granules, reducing the hypochlorous acid production. The loss of Rictor also led to metabolic alterations in isolated neutrophils, increasing aerobic glycolysis. Finally, myeloid-Rictor-deleted mice (LysMRic Δ/Δ) also showed an impairment of the microbicidal capacity, increasing the bacterial burden in the Escherichia coli sepsis model. Overall, our results highlight the importance of proper mTORC2 activation for neutrophil effector functions and metabolism during sepsis.


Assuntos
Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Neutrófilos/metabolismo , Sepse/metabolismo , Sepse/microbiologia , Animais , Quimiotaxia/fisiologia , Escherichia coli/metabolismo , Feminino , Glicólise/fisiologia , Humanos , Ácido Hipocloroso/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/fisiologia , Transdução de Sinais/fisiologia
4.
Exp Parasitol ; 255: 108654, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37956783

RESUMO

In this study, we investigated the microencapsulation of two strains of the entomopathogenic bacteria Bacillus thuringiensis (B. thuringiensis) (BtMA-750 and BtMA-1114), which are biopesticides of high toxicity for the mosquito vector Aedes aegypti. The encapsulation of different concentrations of microorganisms in starch microparticles was evaluated, and the inverse suspension polymerization technique was explored. It was possible to observe that the higher amounts of the biopesticide caused a slight decrease in the diameter of the particles; however, even when encapsulated, the biopesticide still presents an average diameter that is able to be consumed by the larvae of Aedes aegypti. Furthermore, it was noticed that the presence of both of the B. thuringiensis strains did not affect the thermal stability of the particles. The microencapsulated bacterial strains presented a high number of viable spores and preserved the expression of proteins with molecular masses corresponding to the insecticidal toxins Cry and Cyt, indicating that the encapsulation process was conducted satisfactorily. Finally, the encapsulated strains were tested against Ae. aegypti larvae and maintained 100% larval mortality even after 35 days. Therefore, microencapsulation of B. thuringiensis not only guarantees the bacterial activity, but also prolongs the action of the biopesticide. Collectively, such findings highlight the great potential of the new biopesticides, which may help to reduce the population indices of the mosquito vector Ae. aegypti via a sustainable and environment-friendly route.


Assuntos
Aedes , Bacillus thuringiensis , Animais , Agentes de Controle Biológico , Mosquitos Vetores , Proteínas de Bactérias , Larva/microbiologia
5.
Int J Mol Sci ; 24(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37511073

RESUMO

The endogenous estradiol derivative 2-Methoxyestradiol (2-ME) has shown good and wide anticancer activity but suffers from poor oral bioavailability and extensive metabolic conjugation. However, its sulfamoylated derivative, 2-methoxyestradiol-3,17-O,O-bis-sulfamate (STX140), has superior potential as a therapeutic agent, acts by disrupting microtubule polymerization, leading to cell cycle arrest and apoptosis in cancer cells and possesses much better pharmaceutical properties. This study investigated the antiproliferative and anti-invasive activities of STX140 in both SKMEL-28 naïve melanoma (SKMEL28-P) cells and resistant melanoma cells (SKMEL-28R). STX140 inhibited cell proliferation in the nanomolar range while having a less pronounced effect on human melanocytes. Additionally, STX140 induced cell cycle arrest in the G2/M phase and sub-G1, reduced migration, and clonogenic potential in monolayer models, and inhibited invasion in a 3D human skin model with melanoma cells. Furthermore, STX140 induced senescence features in melanoma and activated the senescence machinery by upregulating the expression of senescence genes and proteins related to senescence signaling. These findings suggest that STX140 may hold potential as a therapeutic agent for melanoma treatment.


Assuntos
Estrenos , Melanoma , Humanos , 2-Metoxiestradiol/farmacologia , Estrenos/farmacologia , Proliferação de Células , Melanoma/tratamento farmacológico , Linhagem Celular Tumoral , Apoptose
6.
J Cell Mol Med ; 26(3): 671-683, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35040264

RESUMO

Our previous work using a melanoma progression model composed of melanocytic cells (melanocytes, primary and metastatic melanoma samples) demonstrated various deregulated genes, including a few known lncRNAs. Further analysis was conducted to discover novel lncRNAs associated with melanoma, and candidates were prioritized for their potential association with invasiveness or other metastasis-related processes. In this sense, we found the intergenic lncRNA U73166 (ENSG00000230454) and decided to explore its effects in melanoma. For that, we silenced the lncRNA U73166 expression using shRNAs in a melanoma cell line. Next, we experimentally investigated its functions and found that migration and invasion had significantly decreased in knockdown cells, indicating an essential association of lncRNA U73166 for cancer processes. Additionally, using naïve and vemurafenib-resistant cell lines and data from a patient before and after resistance, we found that vemurafenib-resistant samples had a higher expression of lncRNA U73166. Also, we retrieved data from the literature that indicates lncRNA U73166 may act as a mediator of RNA processing and cell invasion, probably inducing a more aggressive phenotype. Therefore, our results suggest a relevant role of lncRNA U73166 in metastasis development. We also pointed herein the lncRNA U73166 as a new possible biomarker or target to help overcome clinical vemurafenib resistance.


Assuntos
Melanoma , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação para Cima/genética , Vemurafenib/farmacologia
7.
Molecules ; 27(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36144732

RESUMO

Here, we verify the depigmenting action of Pouteria macrophylla fruit extract (EXT), incorporate it into a safe topical microemulsion and assess its effectiveness in a 3D pigmented skin model. Melanocytes-B16F10- were used to assess the EXT effects on cell viability, melanin synthesis, and melanin synthesis-related gene transcription factor expression, which demonstrated a 32% and 50% reduction of intra and extracellular melanin content, respectively. The developed microemulsion was composed of Cremophor EL®/Span 80 4:1 (w/w), ethyl oleate, and pH 4.5 HEPES buffer and had an average droplet size of 40 nm (PdI 0.40 ± 0.07). Skin irritation test with reconstituted epidermis (Skin Ethic RHETM) showed that the formulation is non-irritating. Tyrosinase inhibition was maintained after skin permeation in vitro, in which microemulsion showed twice the inhibition of the conventional emulsion (20.7 ± 2.2% and 10.7 ± 2.4%, respectively). The depigmenting effect of the microemulsion was finally confirmed in a 3D culture model of pigmented skin, in which histological analysis showed a more pronounced effect than a commercial depigmenting formulation. In conclusion, the developed microemulsion is a promising safe formulation for the administration of cutite fruit extract, which showed remarkable depigmenting potential compared to a commercial formulation.


Assuntos
Pouteria , Administração Cutânea , Emulsões/química , Frutas , HEPES/metabolismo , HEPES/farmacologia , Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Pele , Fatores de Transcrição/metabolismo
8.
Eur J Contracept Reprod Health Care ; 27(3): 208-211, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34870546

RESUMO

OBJECTIVES: The aims of the study were to assess the number of insertions per month of the 52 mg levonorgestrel-releasing intrauterine system (LNG-IUS) and gauge the knowledge and opinions of health care providers with regard to some of its characteristics and the reasons why women liked using the method. METHODS: An online questionnaire survey was conducted between January and July 2021 at the University of Campinas, Brazil. The survey comprised physicians and nurses from centres that had requested and received donated devices. RESULTS: A total of 65 health care providers answered the questionnaire (41 physicians and 24 nurses). The main misconceptions were related to insertion after an ectopic pregnancy: 60/65 (92.3%) answered that users with previous ectopic pregnancy must have frequent follow-up. Wrong answers were also given on the occurrence of acne (37/65, 56.9%) and depression (32/65, 49.2%). Participants reported that the LNG-IUS was highly effective (100%), long-acting (93.9%) and an appropriate method for controlling uterine bleeding (90.8%) and that it had few side effects (86.2%). CONCLUSION: Our study suggests that health care providers from centres that requested and received LNG-IUS donations, even though they reported adequate knowledge about the device, still had misconceptions with regard to its clinical management.


Assuntos
Anticoncepcionais Femininos , Dispositivos Intrauterinos Medicados , Gravidez Ectópica , Anticoncepcionais Femininos/efeitos adversos , Feminino , Pessoal de Saúde , Humanos , Dispositivos Intrauterinos Medicados/efeitos adversos , Levanogestrel/efeitos adversos , Gravidez , Gravidez Ectópica/tratamento farmacológico
9.
J Headache Pain ; 23(1): 2, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979899

RESUMO

BACKGROUND: Neurological symptoms are frequent among patients with COVID-19. Little is known regarding the repercussions of neurological symptoms for patients and how these symptoms are related to one another. OBJECTIVES: To determine whether there is an association between the neurological symptoms in patients with COVID-19, and to characterize the headache. METHOD: This was a cross-sectional study. All hospital inpatients and health workers at the Hospital Universitario Oswaldo Cruz with a PCR-confirmed COVID-19 infection between March and June 2020 were considered for the study and were interviewed by telephone at least 2-months after the acute phase of the disease. These patients were identified by the hospital epidemiological surveillance department. A semi-structured questionnaire was used containing sociodemographic and clinical data and the ID-Migraine. RESULTS: A total of 288 patients was interviewed; 53.1% were male; with a median age of 49.9 (41.5-60.5) years; 91.7% presented some neurological symptom; 22.2% reported some neurological symptom as the symptom that troubled them most during COVID-19. Neurological symptoms were: ageusia (69.8%), headache (69.1%), anosmia (67%), myalgia (44.4%), drowsiness (37.2%), agitation (20.8%); mental confusion (14.9%), syncope (4.9%) and epileptic seizures (2.8%). Females, those who presented with fever, sore throat, anosmia/ageusia and myalgia also presented significantly more with headache (logistic regression). The most frequent headache phenotype was a non-migraine phenotype, was of severe intensity and differed from previous headaches. This persisted for more than 30 days in 18% and for more than 90 days in 10% of patients. Thirteen percent of those with anosmia and 11% with ageusia continued with these complaints after more than 90 days of the acute phase of the disease. Aged over 50 years, agitation and epileptic seizures were significantly associated with mental confusion (logistic regression). CONCLUSION: Headache is frequent in COVID-19, is associated with other symptoms such as fever, sore throat, anosmia, ageusia, and myalgia, and may persist beyond the acute phase of the disease.


Assuntos
Ageusia , COVID-19 , Idoso , Anosmia , Estudos Transversais , Feminino , Cefaleia/epidemiologia , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2
10.
Pharmacol Res ; 173: 105911, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34560251

RESUMO

In melanomas, therapy resistance can arise due to a combination of genetic, epigenetic and phenotypic mechanisms. Due to its crucial role in DNA supercoil relaxation, TOP1 is often considered an essential chemotherapeutic target in cancer. However, how TOP1 expression and activity might differ in therapy sensitive versus resistant cell types is unknown. Here we show that TOP1 expression is increased in metastatic melanoma and correlates with an invasive gene expression signature. More specifically, TOP1 expression is highest in cells with the lowest expression of MITF, a key regulator of melanoma biology. Notably, TOP1 and DNA Single-Strand Break Repair genes are downregulated in BRAFi- and BRAFi/MEKi-resistant cells and TOP1 inhibition decreases invasion markers only in BRAFi/MEKi-resistant cells. Thus, we show three different phenotypes related to TOP1 levels: i) non-malignant cells with low TOP1 levels; ii) metastatic cells with high TOP1 levels and high invasiveness; and iii) BRAFi- and BRAFi/MEKi-resistant cells with low TOP1 levels and high invasiveness. Together, these results highlight the potential role of TOP1 in melanoma progression and resistance.


Assuntos
DNA Topoisomerases Tipo I , Resistencia a Medicamentos Antineoplásicos , Melanoma , Neoplasias Cutâneas , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/mortalidade
11.
J Biol Chem ; 292(21): 8705-8715, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28348082

RESUMO

Urate hydroperoxide is a product of the oxidation of uric acid by inflammatory heme peroxidases. The formation of urate hydroperoxide might be a key event in vascular inflammation, where there is large amount of uric acid and inflammatory peroxidases. Urate hydroperoxide oxidizes glutathione and sulfur-containing amino acids and is expected to react fast toward reactive thiols from peroxiredoxins (Prxs). The kinetics for the oxidation of the cytosolic 2-Cys Prx1 and Prx2 revealed that urate hydroperoxide oxidizes these enzymes at rates comparable with hydrogen peroxide. The second-order rate constants of these reactions were 4.9 × 105 and 2.3 × 106 m-1 s-1 for Prx1 and Prx2, respectively. Kinetic and simulation data suggest that the oxidation of Prx2 by urate hydroperoxide occurs by a three-step mechanism, where the peroxide reversibly associates with the enzyme; then it oxidizes the peroxidatic cysteine, and finally, the rate-limiting disulfide bond is formed. Of relevance, the disulfide bond formation was much slower in Prx2 (k3 = 0.31 s-1) than Prx1 (k3 = 14.9 s-1). In addition, Prx2 was more sensitive than Prx1 to hyperoxidation caused by both urate hydroperoxide and hydrogen peroxide. Urate hydroperoxide oxidized Prx2 from intact erythrocytes to the same extent as hydrogen peroxide. Therefore, Prx1 and Prx2 are likely targets of urate hydroperoxide in cells. Oxidation of Prxs by urate hydroperoxide might affect cell function and be partially responsible for the pro-oxidant and pro-inflammatory effects of uric acid.


Assuntos
Eritrócitos/enzimologia , Peróxidos/química , Peroxirredoxinas/química , Ácido Úrico/análogos & derivados , Dissulfetos/química , Dissulfetos/metabolismo , Humanos , Cinética , Oxirredução , Peróxidos/metabolismo , Peroxirredoxinas/metabolismo , Ácido Úrico/química , Ácido Úrico/metabolismo
12.
Clin Exp Pharmacol Physiol ; 44(10): 971-979, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28649767

RESUMO

Antineoplastic drugs such as cisplatin, oxaliplatin, paclitaxel and vincristin are widely used in the treatment of several solid and blood tumours. However, the severity of peripheral neuropathy caused by these agents can affect the patient's quality of life. The major symptoms of chemotherapy-induced peripheral neuropathy (CIPN) involve: sensory loss, paresthesia, dysesthaesia, numbness, tingling, temperature sensitivity, allodynia and hyperalgesia, in a "stocking and glove" distribution. Why many different chemotherapeutic agents result in similar neuropathy profiles is unclear. Many drug classes such as antidepressants, anticonvulsants, antispastic agents and others have been used in clinical practice, but there is no scientific evidence to prove their effectiveness. But drugs as the antioxidant have shown a protective effect against free radical damage. In order to find out a successful treatment for CIPN, animal studies (ie pharmacological and mechanical tests and histopathological immunohistochemical analyses) have been developed to try to determinate the action of the antioxidant agents. This review provides an overview of the major antioxidant agents recently investigated to treat CIPN and the animal models used for this purpose.


Assuntos
Antineoplásicos/efeitos adversos , Antioxidantes/farmacologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Animais , Antioxidantes/uso terapêutico , Modelos Animais de Doenças
13.
Arch Phys Med Rehabil ; 98(5): 849-855, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27794485

RESUMO

OBJECTIVE: To evaluate the effect of noninvasive ventilation (NIV) on exercise performance in individuals with heart failure (HF). DESIGN: Crossover, blind, randomized controlled trial with allocation concealment. SETTING: University-based research laboratory. PARTICIPANTS: Participants (N=24) with New York Heart Association class II and III left heart failure and with a mean age of 51.8±10.2 years (women: n=8; men: n=16). INTERVENTIONS: Ventilatory support attached to the face of the individual via a facemask prior to cardiopulmonary exercise test (CPET) was administered at 2 pressure levels for 30 minutes. Inspiratory pressure of 15cmH2O and expiratory pressure of 5cmH2O were applied. MAIN OUTCOME MEASURES: Maximal oxygen uptake, maximum heart rate, variation between the initial and maximum heart rates, CPET duration, and recovery time oxygen consumption. RESULTS: Differences were observed in maximal oxygen consumption (nonintervention phase: 18.3±4.4mL·kg-1·min-1 vs NIV phase: 20.6±4.9mL·kg-1·min-1, P=.01), heart rate (nonintervention phase: 127.3±20.9 beats per minute vs NIV phase: 134.7±19.5 beats per minute, P=.04), and heart rate variation (nonintervention phase: 63.3%±19.3% vs NIV phase: 69.7%±16.6%, P=.02). Moreover, differences in cardiopulmonary exercise time (nonintervention phase: 7.4±1.5min vs NIV phase: 8.3±1.7min, P=.01) and oxygen consumption recovery time (nonintervention phase: 2.8±1.0min vs NIV phase: 2.4±0.8min, P=.01) were observed. CONCLUSIONS: NIV elicited beneficial effects in the HF population that included increased exercise tolerance, recovery time optimization, and improved chronotropic and respiratory reserves.


Assuntos
Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/reabilitação , Ventilação não Invasiva/métodos , Adulto , Idoso , Estudos Cross-Over , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Testes de Função Respiratória , Método Simples-Cego
14.
Asian-Australas J Anim Sci ; 30(1): 51-56, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26954203

RESUMO

OBJECTIVE: The objective of this study was to evaluate the intake and nutrient digestibility, nitrogen balance and ruminal ammonia nitrogen in lambs of diets containing different levels of residual frying oil. METHODS: Levels of 0, 20, 40, 60, and 80 g/kg dry matter (DM) base of residual frying oil in the diets of lambs were evaluated. Five castrated lambs with initial body weights of 36.8±3.3 kg, distributed in a Latin square (5×5) design, were used. RESULTS: There was a decreasing linear effect on the intake of DM, organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), total carbohydrates (TCH), and nonfibrous carbohydrates (NFC). There was an increased linear intake of ether extract (EE). The apparent digestibility of DM, OM, CP, NDF, TCH, and NFC, as well as urine nitrogen excretion, nitrogen balance and ruminal parameters, were not influenced by different levels of residual frying oil in the diet. EE digestibility presented a crescent linear effect. CONCLUSION: It can be concluded that the addition of residual frying oil to the diets of sheep can affect nutrient intake without affecting the digestibility of most nutrients (with the exception of EE), nitrogen balance and ruminal ammonia nitrogen concentration.

15.
Chem Res Toxicol ; 28(8): 1556-66, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26207674

RESUMO

Urate hydroperoxide is a strong oxidant generated by the combination of urate free radical and superoxide. The formation of urate hydroperoxide as an intermediate in urate oxidation is potentially responsible for the pro-oxidant effects of urate in inflammatory disorders, protein degradation, and food decomposition. To understand the molecular mechanisms that sustain the harmful effects of urate in inflammatory and oxidative stress related conditions, we report a detailed structural characterization and reactivity of urate hydroperoxide toward biomolecules. Urate hydroperoxide was synthesized by photo-oxidation and by a myeloperoxidase/hydrogen peroxide/superoxide system. Multiple reaction monitoring (MRM) and MS(3) ion fragmentation revealed that urate hydroperoxide from both sources has the same chemical structure. Urate hydroperoxide has a maximum absorption at 308 nm, ε308nm = 6.54 ± 0.38 × 10(3) M(-1) cm(-1). This peroxide decays spontaneously with a rate constant of k = 2.80 ± 0.18 × 10(-4) s(-1) and a half-life of 41 min at 22 °C. Urate hydroperoxide undergoes electrochemical reduction at potential values less negative than -0.5 V (versus Ag/AgCl). When incubated with taurine, histidine, tryptophan, lysine, methionine, cysteine, or glutathione, urate hydroperoxide reacted only with methionine, cysteine, and glutathione. The oxidation of these molecules occurred by a two-electron mechanism, generating the alcohol, hydroxyisourate. No adduct between cysteine or glutathione and urate hydroperoxide was detected. The second-order rate constant for the oxidation of glutathione by urate hydroperoxide was 13.7 ± 0.8 M(-1) s(-1). In conclusion, the oxidation of sulfur-containing biomolecules by urate hydroperoxide is likely to be a mechanism by which the pro-oxidant and damaging effects of urate are mediated in inflammatory and photo-oxidizing processes.


Assuntos
Peróxido de Hidrogênio/química , Luz , Peróxidos/química , Ácido Úrico/análogos & derivados , Ácido Úrico/química , Cromatografia Líquida , Glutationa/química , Cinética , Estrutura Molecular , Oxirredução , Estresse Oxidativo , Espectrometria de Massas por Ionização por Electrospray , Ácido Úrico/metabolismo
16.
Korean J Pain ; 37(3): 247-255, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38881283

RESUMO

Background: Little is known about the frequency and impact of the persistent headache and about the incidence of chronic daily headache (CDH) after coronavirus disease 2019 (COVID-19). The aim of this prospective cohort study was to assess the incidence, risk factors, characteristics, and impact of CDH in patients with COVID-19. Methods: In the first stage, 288 patients were interviewed by telephone after the acute phase of COVID-19. Subsequently, 199 patients who presented headache were reinterviewed at least one year after COVID-19. Headaches that persisted beyond the acute phase of COVID-19 for three or more months and presented frequency ≥ 45 days over the first three months were considered to be CDH. Results: One hundred and twenty-three patients were included, 56% were females; median age: 50 years (25th and 75th percentile: 41;58). The headache persisted beyond the acute phase of COVID-19 in 52%, and 20.3% had CDH (95% confidence interval: 13.6-28.2). Individuals who previously had headaches and who had headaches of greater intensity during the acute phase were at higher risk of developing CDH. The group with CDH included more females, greater impact of headache, more persistence of headache beyond the 120th day of COVID-19 and less throbbing headache than did the other individuals whose headache persisted. Conclusions: Patients who had COVID-19 had a high incidence of CDH. Previous headache and greater intensity of headache were associated with higher risk of CDH.

17.
Biomed Pharmacother ; 177: 116953, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38955087

RESUMO

The second most common mutation in melanoma occurs in NRAS oncogene, being a more aggressive disease that has no effective approved treatment. Besides, cellular plasticity limits better outcomes of the advanced and therapy-resistant patients. Peroxiredoxins (PRDXs) control cellular processes through direct hydrogen peroxide oxidation or by redox-relaying processes. Here, we demonstrated that PRDX2 could act as a modulator of multiple EMT markers in NRAS-mutated melanomas. PRDX2 knockdown lead to phenotypic changes towards invasion in human reconstructed skin and the treatment with a PRDX mimetic (gliotoxin), decreased migration in PRDX2-deficient cells. We also confirmed the favorable clinical outcome of patients expressing PRDX2 in a large primary melanoma cohort. This study contributes to our knowledge about genes involved in phenotype switching and opens a new perspective for PRDX2 as a biomarker and target in NRAS-mutated melanomas.

18.
Antioxidants (Basel) ; 13(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38790661

RESUMO

Microenvironment and transcriptional plasticity generate subpopulations within the tumor, and the use of BRAF inhibitors (BRAFis) contributes to the rise and selection of resistant clones. We stochastically isolated subpopulations (C1, C2, and C3) from naïve melanoma and found that the clones demonstrated distinct morphology, phenotypic, and functional profiles: C1 was less proliferative, more migratory and invasive, less sensitive to BRAFis, less dependent on OXPHOS, more sensitive to oxidative stress, and less pigmented; C2 was more proliferative, less migratory and invasive, more sensitive to BRAFis, less sensitive to oxidative stress, and more pigmented; and C3 was less proliferative, more migratory and invasive, less sensitive to BRAFis, more dependent on OXPHOS, more sensitive to oxidative stress, and more pigmented. Hydrogen peroxide plays a central role in oxidative stress and cell signaling, and PRDXs are one of its main consumers. The intrinsically resistant C1 and C3 clones had lower MITF, PGC-1α, and PRDX1 expression, while C1 had higher AXL and decreased pigmentation markers, linking PRDX1 to clonal heterogeneity and resistance. PRDX2 is depleted in acquired BRAFi-resistant cells and acts as a redox sensor. Our results illustrate that decreased pigmentation markers are related to therapy resistance and decreased antioxidant defense.

19.
Front Med (Lausanne) ; 11: 1400423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835799

RESUMO

Hansen's disease, or leprosy, is a disease characterized by dermatological and neurological disorders. A neural form also exists, in which peripheral neuropathy occurs in the absence of skin lesions. However, cases of leprosy that involve the central nervous system and proximal nerves are rare in the literature. We describe the case of an oligosymptomatic patient diagnosed with the neural form of leprosy with involvement of peripheral nerves, dorsal root ganglion, and cervical spinal cord in an atypical presentation of the disease. Through complementary examinations and nerve biopsies, the bacillus was identified, and treatment was subsequently initiated. This case highlights the importance of investigating the suspicion of leprosy, even in cases with atypical manifestations, as early diagnosis and treatment can reduce neurological damage and deformities.

20.
Neoplasia ; 46: 100947, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913653

RESUMO

Acral melanoma is a rare subtype of melanoma that arises on the non-hair bearing skin of the nail bed, palms of the hand and soles of the feet. It is unique among melanomas in not being linked to ultraviolet radiation (UVR) exposure from the sun, and, as such, its incidence is similar across populations who are of Asian, Hispanic, African and European origin. Although research into acral melanoma has lagged behind that of sun-exposed cutaneous melanoma, recent studies have begun to address the unique genetics and immune features of acral melanoma. In this review we will discuss the latest progress in understanding the biology of acral melanoma across different ethnic populations and will outline how these new discoveries can help to guide the therapeutic management of this rare tumor.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/genética , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/tratamento farmacológico , Raios Ultravioleta/efeitos adversos , Genômica , Melanoma Maligno Cutâneo
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