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1.
BMC Health Serv Res ; 24(1): 169, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321433

RESUMO

BACKGROUND: The presence of chronic conditions such as type 2 diabetes mellitus (T2DM) requires behavioral lifestyle changes mediated by individuals' motivation for change and adherence to treatment. This study aims to explore activation levels in individuals with T2DM treated in primary care facilities and to identify the association between demographic, clinical, psychosocial factors, and patient activation amongst populations in the Brazilian state of Amazonas. METHODS: SAPPA is a cross-sectional study conducted in Amazonas, approved by the Universidade Federal do Amazona's IRB in Brazil. Individuals with T2DM were evaluated in their homes (n = 4,318,325). The variables were sex, age, skin color, education level; health-related variables such as body mass index, nutritional behavior, and frequency of physical activity. Measures related to patient self-management behaviors over the past 6 months (Patient Activation Measure - PAM-13) were included in the survey. Descriptive and frequency data are presented as mean (standard deviation (SD)) or numeric percentage). Statistical testing was performed using IBM SPSS V.26, and a p-value of < 0.050 showed significance. Activation levels were dichotomized into low activation (Levels 1 and 2) and high activation (Levels 3 and 4). A multivariate linear model assessed the association between the PAM-13 score and the following variables: age, sex, BMI, skin color, number of comorbidities, burden of symptoms, and number of medications. RESULTS: Logistic regression analyses indicated a statistically significant association between sex, age, education, self-rated health, and general satisfaction with life. men were 43% more likely to score lower levels (p < 0.001). The results also indicated that advanced age had lower PAM levels (p < 0.001). Participants with fewer years of education were 44% more likely to have lower levels of PAM (p = 0.03). Worse self-rated health (p < 0.001) and lower general life satisfaction (p = 0.014) were associated with lower PAM levels. CONCLUSIONS: Low patient activation was associated with worse sociodemographic, health, and psychological conditions in the Amazon population. The low level of patient activation observed in this sample highlights an important impediment to diabetes disease management/self-management in disadvantaged populations.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Diabetes Mellitus Tipo 2/terapia , Estudos Transversais , Brasil , Participação do Paciente , Fatores Socioeconômicos
2.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396953

RESUMO

Biosynthetic gold nanoparticles (bAuNPs) present a promising avenue for enhancing bio-compatibility and offering an economically and environmentally responsible alternative to traditional production methods, achieved through a reduction in the use of hazardous chemicals. While the potential of bAuNPs as anticancer agents has been explored, there is a limited body of research focusing on the crucial physicochemical conditions influencing bAuNP production. In this study, we aim to identify the optimal growth phase of Pseudomonas aeruginosa cultures that maximizes the redox potential and coordinates the formation of bAuNPs with increased efficiency. The investigation employs 2,6-dichlorophenolindophenol (DCIP) as a redox indicator. Simultaneously, we explore the impact of temperature, pH, and incubation duration on the biosynthesis of bAuNPs, with a specific emphasis on their potential application as antitumor agents. Characterization of the resulting bAuNPs is conducted using ATR-FT-IR, TEM, and UV-Vis spectroscopy. To gain insights into the anticancer potential of bAuNPs, an experimental model is employed, utilizing both non-neoplastic (HPEpiC) and neoplastic (PC3) epithelial cell lines. Notably, P. aeruginosa cultures at 9 h/OD600 = 1, combined with biosynthesis at pH 9.0 for 24 h at 58 °C, produce bAuNPs that exhibit smaller, more spherical, and less aggregated characteristics. Crucially, these nanoparticles demonstrate negligible effects on HPEpiC cells while significantly impacting PC3 cells, resulting in reduced viability, migration, and lower IL-6 levels. This research lays the groundwork for the development of more specialized, economical, and ecologically friendly treatment modalities.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Neoplasias da Próstata , Humanos , Masculino , Antibacterianos/química , Ouro/química , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Química Verde/métodos , Extratos Vegetais/química
3.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36136729

RESUMO

Protein evolution depends on the adaptation of these molecules to different functional challenges. This occurs by tuning their biochemical, biophysical, and structural traits through the accumulation of mutations. While the role of protein dynamics in biochemistry is well recognized, there are limited examples providing experimental evidence of the optimization of protein dynamics during evolution. Here we report an NMR study of four variants of the CTX-M ß-lactamases, in which the interplay of two mutations outside the active site enhances the activity against a cephalosporin substrate, ceftazidime. The crystal structures of these enzymes do not account for this activity enhancement. By using NMR, here we show that the combination of these two mutations increases the backbone dynamics in a slow timescale and the exposure to the solvent of an otherwise buried ß-sheet. The two mutations located in this ß-sheet trigger conformational changes in loops located at the opposite side of the active site. We postulate that the most active variant explores alternative conformations that enable binding of the more challenging substrate ceftazidime. The impact of the mutations in the dynamics is context-dependent, in line with the epistatic effect observed in the catalytic activity of the different variants. These results reveal the existence of a dynamic network in CTX-M ß-lactamases that has been exploited in evolution to provide a net gain-of-function, highlighting the role of alternative conformations in protein evolution.


Assuntos
Ceftazidima , Escherichia coli , Antibacterianos/farmacologia , Ceftazidima/química , Ceftazidima/farmacologia , Cefalosporinas/farmacologia , Escherichia coli/genética , Solventes/farmacologia , beta-Lactamases/metabolismo
4.
Arch Biochem Biophys ; 738: 109557, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878339

RESUMO

Integrins are a family of heterodimeric transmembrane receptors which link the extracellular matrix to the cell cytoskeleton. These receptors play a role in many cellular processes: adhesion, proliferation, migration, apoptosis, and platelet aggregation, thus modulating a wide range of scenarios in health and disease. Therefore, integrins have been the target of new antithrombotic drugs. Disintegrins from snake venoms are recognized by the ability to modulate the activity of integrins, such as integrin αIIbß3, a fundamental platelet glycoprotein, and αvß3 expressed on tumor cells. For this reason, disintegrins are unique and potential tools for examining integrin-matrix interaction and the development of novel antithrombotic agents. The present study aims to obtain the recombinant form of jararacin and evaluate the secondary structure and its effects on hemostasis and thrombosis. rJararacin was expressed in the Pichia pastoris (P. pastoris) expression system and purified the recombinant protein with a yield of 40 mg/L of culture. The molecular mass (7722 Da) and internal sequence were confirmed by mass spectrometry. Structure and folding analysis were obtained by Circular Dichroism and 1H Nuclear Magnetic Resonance spectra. Disintegrin structure reveals properly folded with the presence of ß-sheet structure. rJararacin significantly demonstrated inhibition of the adhesion of B16F10 cells and platelets to the fibronectin matrix under static conditions. rJararacin inhibited platelet aggregation induced by ADP (IC50 95 nM), collagen (IC50 57 nM), and thrombin (IC50 22 nM) in a dose-dependent manner. This disintegrin also inhibited 81% and 94% of the adhesion of platelets to fibrinogen and collagen under continuous flow, respectively. In addition, rjararacin efficaciously prevents platelet aggregation in vitro and ex vivo with rat platelets and thrombus occlusion at an effective dose (5 mg/kg). The data here provides evidence that rjararacin possesses the potential as an αIIbß3 antagonist, capable of preventing arterial thrombosis.


Assuntos
Venenos de Crotalídeos , Trombose , Ratos , Animais , Desintegrinas/farmacologia , Desintegrinas/química , Desintegrinas/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/química , Venenos de Crotalídeos/química , Venenos de Crotalídeos/farmacologia , Agregação Plaquetária , Hemostasia , Integrinas/metabolismo , Trombose/tratamento farmacológico
5.
Proteins ; 90(9): 1655-1668, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35430767

RESUMO

Klebsiella pneumoniae is an opportunistic pathogen, which concerns public health systems worldwide, as multiple antibiotic-resistant strains are frequent. One of its pathogenicity factors is the Type VI Secretion System (T6SS), a macromolecular complex assembled through the bacterial membranes. T6SS injects effector proteins inside target cells. Such effectors confer competitive advantages or modulate the target cell signaling and metabolism to favor bacterial infection. The VgrG protein is a T6SS core component. It may present a variable C-terminal domain carrying an additional effector function. Kp52.145 genome encodes three VgrG proteins, one of them with a C-terminal extension (VgrG4-CTD). VgrG4-CTD is 138 amino acids long, does not contain domains of known function, but is conserved in some Klebsiella, and non-Klebsiella species. To get insights into its function, recombinant VgrG4-CTD was used in pulldown experiments to capture ligands from macrophages and lung epithelial cells. A total of 254 proteins were identified: most of them are ribosomal proteins. Cytoskeleton-associated and proteins involved in the phagosome maturation pathway were also identified. We further showed that VgrG4-CTD binds actin and induces actin remodeling in macrophages. This study presents novel clues on the role of K. pneumoniae T6SS in pathogenesis.


Assuntos
Klebsiella pneumoniae , Sistemas de Secreção Tipo VI , Citoesqueleto de Actina/metabolismo , Actinas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo , Fatores de Virulência
6.
J Enzyme Inhib Med Chem ; 37(1): 287-298, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34894959

RESUMO

We synthesised and screened 18 aromatic derivatives of guanylhydrazones and oximes aromatic for their capacity to bind to dengue virus capsid protein (DENVC). The intended therapeutic target was the hydrophobic cleft of DENVC, which is a region responsible for its anchoring in lipid droplets in the infected cells. The inhibition of this process completely suppresses virus infectivity. Using NMR, we describe five compounds able to bind to the α1-α2 interface in the hydrophobic cleft. Saturation transfer difference experiments showed that the aromatic protons of the ligands are important for the interaction with DENVC. Fluorescence binding isotherms indicated that the selected compounds bind at micromolar affinities, possibly leading to binding-induced conformational changes. NMR-derived docking calculations of ligands showed that they position similarly in the hydrophobic cleft. Cytotoxicity experiments and calculations of in silico drug properties suggest that these compounds may be promising candidates in the search for antivirals targeting DENVC.


Assuntos
Antivirais/farmacologia , Proteínas do Capsídeo/antagonistas & inibidores , Vírus da Dengue/efeitos dos fármacos , Hidrazonas/farmacologia , Oximas/farmacologia , Antivirais/síntese química , Antivirais/química , Proteínas do Capsídeo/metabolismo , Vírus da Dengue/metabolismo , Relação Dose-Resposta a Droga , Hidrazonas/síntese química , Hidrazonas/química , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oximas/síntese química , Oximas/química , Relação Estrutura-Atividade
7.
Comput Inform Nurs ; 40(6): 373-381, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34812780

RESUMO

There is increasing debate about the importance of using information and communication technologies to strengthen health systems. Information systems are one of the most widespread technologies for this end in different healthcare contexts. The primary objective of this study was to highlight and discuss the main characteristics of the regulation and use of health information systems in Brazil and abroad. As a secondary objective, the main characteristics identified in Brazil were compared with the findings for other countries. A robust search strategy incorporated five electronic databases. The research question was defined using the SPIDER strategy, and thematic content analysis was applied. Fourteen articles composed the final sample, and three analytic categories were identified: "Use in the Context of Health Systems"; "Implications for Health Management"; and "Communication and Interoperability." The regulation and use of health information systems in different countries was directly related to their socioeconomic context. In Latin America and Africa, policy strengthening and implementation possibilities for health management were discussed. In the United States, Europe, and Asia, the discussions on interoperability between different services was emphasized. The complexity of the Brazilian health system leads to similarities in the data analysis with several countries from different regions and with distinct political configurations.


Assuntos
Sistemas de Informação em Saúde , África , Ásia , Brasil , Humanos , América Latina , Estados Unidos
8.
Biophys J ; 120(14): 2814-2827, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34197802

RESUMO

The nucleocapsid (N) protein of betacoronaviruses is responsible for nucleocapsid assembly and other essential regulatory functions. The N protein N-terminal domain (N-NTD) interacts and melts the double-stranded transcriptional regulatory sequences (dsTRSs), regulating the discontinuous subgenome transcription process. Here, we used molecular dynamics (MD) simulations to study the binding of the severe acute respiratory syndrome coronavirus 2 N-NTD to nonspecific (NS) and TRS dsRNAs. We probed dsRNAs' Watson-Crick basepairing over 25 replicas of 100 ns MD simulations, showing that only one N-NTD of dimeric N is enough to destabilize dsRNAs, triggering melting initiation. dsRNA destabilization driven by N-NTD was more efficient for dsTRSs than dsNS. N-NTD dynamics, especially a tweezer-like motion of ß2-ß3 and Δ2-ß5 loops, seems to play a key role in Watson-Crick basepairing destabilization. Based on experimental information available in the literature, we constructed kinetics models for N-NTD-mediated dsRNA melting. Our results support a 1:1 stoichiometry (N-NTD/dsRNA), matching MD simulations and raising different possibilities for N-NTD action: 1) two N-NTD arms of dimeric N would bind to two different RNA sites, either closely or spatially spaced in the viral genome, in a cooperative manner; and 2) monomeric N-NTD would be active, opening up the possibility of a regulatory dissociation event.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteínas do Nucleocapsídeo/genética , Nucleoproteínas , RNA
9.
J Virol ; 94(23)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32938771

RESUMO

The human respiratory syncytial virus (hRSV) M2-1 protein functions as a processivity and antitermination factor of the viral polymerase complex. Here, the first evidence that the hRSV M2-1 core domain (cdM2-1) alone has an unfolding activity for long RNAs is presented and the biophysical and dynamic characterization of the cdM2-1/RNA complex is provided. The main contact region of cdM2-1 with RNA was the α1-α2-α5-α6 helix bundle, which suffered local conformational changes and promoted the RNA unfolding activity. This activity may be triggered by base-pairing recognition. RNA molecules wrap around the whole cdM2-1, protruding their termini over the domain. The α2-α3 and α3-α4 loops of cdM2-1 were marked by an increase in picosecond internal motions upon RNA binding, even though they are not directly involved in the interaction. The results revealed that the cdM2-1/RNA complex originates from a fine-tuned binding, contributing to the unraveling interaction aspects necessary for M2-1 activity.IMPORTANCE The main outcome is the molecular description of the fine-tuned binding of the cdM2-1/RNA complex and the provision of evidence that the domain alone has unfolding activity for long RNAs. This binding mode is essential in the understanding of the function in the full-length protein. Human respiratory syncytial virus (hRSV), an orthopneumovirus, stands out for the unique role of its M2-1 protein as a transcriptional antitermination factor able to increase RNA polymerase processivity.


Assuntos
RNA/química , RNA/metabolismo , Vírus Sincicial Respiratório Humano/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo , Sítios de Ligação , RNA Polimerases Dirigidas por DNA/metabolismo , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Vírus Sincicial Respiratório Humano/genética , Proteínas Virais/genética
10.
Blood ; 134(8): 699-708, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31133602

RESUMO

Ixolaris is a potent tick salivary anticoagulant that binds coagulation factor Xa (FXa) and zymogen FX, with formation of a quaternary tissue factor (TF)/FVIIa/ FX(a)/Ixolaris inhibitory complex. Ixolaris blocks TF-induced coagulation and PAR2 signaling and prevents thrombosis, tumor growth, and immune activation. We present a high-resolution structure and dynamics of Ixolaris and describe the structural basis for recognition of FX. Ixolaris consists of 2 Kunitz domains (K1 and K2) in which K2 is strikingly dynamic and encompasses several residues involved in FX binding. This indicates that the backbone plasticity of K2 is critical for Ixolaris biological activity. Notably, a nuclear magnetic resonance-derived model reveals a mechanism for an electrostatically guided, high-affinity interaction between Ixolaris and FX heparin-binding (pro)exosite, resulting in an allosteric switch in the catalytic site. This is the first report revealing the structure-function relationship of an anticoagulant targeting a zymogen serving as a scaffold for TF inhibition.


Assuntos
Inibidores do Fator Xa/química , Inibidores do Fator Xa/farmacologia , Fator Xa/metabolismo , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/farmacologia , Animais , Fator Xa/química , Humanos , Simulação de Acoplamento Molecular , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Domínios Proteicos , Carrapatos/química
11.
Support Care Cancer ; 29(11): 6441-6447, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33893842

RESUMO

PURPOSE: The objective of the present study was to compare the efficacy of photobiomodulation with low-level laser therapy (LLLT) or light-emitting diode therapy (LEDT) devices for the prevention and treatment of oral mucositis in pediatric patients diagnosed with acute lymphoblastic leukemia undergoing chemotherapy with high doses of methotrexate (MTX). METHODS: Eighty patients were randomly divided into two groups: LLLT and LEDT. Both protocols were applied with the same energy and radiant exposure. The protocols started in the beginning of high doses MTX and finished when the patients were discharged from the hospital or there was oral mucositis resolution. The oral mucositis was assessed during each session in accordance to the World Health Organization (WHO) score. The patients' self-assessed pain was scored on a visual analog scale (VAS). RESULTS: The incidence of oral mucositis was similar to LLLT and LEDT, 10% and 12.5%, respectively. Both groups required the same number of days to reach score of zero for mucositis and pain (p > 0. 05), and there was no significant difference in mean VAS between the groups. CONCLUSIONS: These findings suggest that LEDT has similar effects to LLLT to avoid and treat oral mucositis. Brazilian Clinical Trial Registry with #U1111-1221-5943.


Assuntos
Terapia com Luz de Baixa Intensidade , Mucosite , Estomatite , Criança , Humanos , Lasers , Metotrexato/efeitos adversos , Estudos Prospectivos , Estomatite/etiologia
12.
BMC Public Health ; 21(1): 1568, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407782

RESUMO

BACKGROUND: Addressing overweight and obesity among men at-risk for obesity-related diseases and disability in rural communities is a public health issue. Commercial smartphone applications (apps) that promote self-monitoring for weight loss are widely available. Evidence is lacking regarding what support is required to enhance user engagement with and effectiveness of those technologies. Pragmatically comparing these apps effectiveness, including rural men's desired forms of support when using them, can lead to greater weight loss intervention impact and reach. This study assessed the feasibility and acceptability of a mobile technology application applied differently across two groups for weight loss. METHODS: In a two-armed, pragmatic pilot feasibility study, 80 overweight and obese men aged 40-69 were randomized using a 1:1 ratio to either an enhanced Mobile Technology Plus (MT+) intervention or a basic Mobile Technology (MT) intervention. The MT+ group had an enhanced smartphone app for self-monitoring (text messaging, discussion group, Wi-Fi scale) whereas the MT group received a basic app that allowed self-monitoring logging only. Assessments were collected at baseline, 3 and 6 months. App logs were analyzed to track engagement and adherence to self-monitoring. Acceptability was assessed via focus groups. Analysis included descriptive statistics and qualitative content analysis. RESULTS: Of 80 men recruited, forty were allocated to each arm. All were included in the primary analysis. Recruitment ended after 10 months with a 97.5 and 92.5% (3 month, 6 month) retention rate. Over 90% of men reported via survey and focus groups that Lose-It app and smart scale (MT+) was an acceptable way to self-monitor weight, dietary intake and physical activity. Adherence to daily app self-monitoring of at least 800 dietary calories or more (reported respectively as MT+, MT) was positive with 73.4, 51.6% tracking at least 5 days a week. Adherence to tracking activity via recorded steps four or more days weekly was positive, 87.8, 64.6%. Men also adhered to self-weighing at least once weekly, 64, 46.3%. At 6 months, an observed mean weight loss was 7.03 kg (95% CI: 3.67, 10.39) for MT+ group and 4.14 kg (95% CI: 2.22, 6.06) for MT group, with 42.9 and 34.2% meeting ≥5% weight loss, respectively. No adverse events were reported. CONCLUSIONS: This National Institutes of Health-funded pilot study using mobile technologies to support behavior change for weight loss was found to be feasible and acceptable among midlife and older rural men. The interventions demonstrated successful reductions in weight, noting differing adherence to lifestyle behaviors of eating, monitoring and activity between groups, with men in the MT+ having more favorable results. These findings will be used to inform the design of a larger scale, clinical trial. TRIAL REGISTRATION: The trial was prospectively registered with ClinicalTrials NCT03329079 . 11/1/2017.


Assuntos
Aplicativos Móveis , Telemedicina , Estudos de Viabilidade , Humanos , Masculino , Projetos Piloto , População Rural , Redução de Peso
13.
Proteins ; 88(1): 242-246, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31294889

RESUMO

Pisum sativum defensin 2 (Psd2) is a small (4.7 kDa) antifungal peptide whose structure is held together by four conserved disulfide bridges. Psd2 shares the cysteine-stabilized alpha-beta (CSαß) fold, which lacks a regular hydrophobic core. All hydrophobic residues are exposed to the surface, except for leucine 6. They are clustered in the surface formed by two loops, between ß1 and α-helix and ß2 and ß3 sheets. The observation of surface hydrophobic clusters reveals a remarkable evolution of the CSαß fold to expose and reorganize hydrophobic residues, which facilitates creating versatile binding sites.


Assuntos
Defensinas/química , Pisum sativum/química , Proteínas de Plantas/química , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Dobramento de Proteína
14.
J Oral Pathol Med ; 49(10): 1053-1060, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32740989

RESUMO

OBJECTIVES: The present study investigated the correlation between the expression of DNA methyltransferase (DNMT)1, DNMT3A, and DNMT3B and the proliferation of mucoepidermoid carcinomas (MECs) using the molecular markers Ki-67 and cyclin D1. This study also demonstrates the effects of 5-aza-2-deoxycytidine (5AC) on the MEC tumor cell lines in relation to DNMT1 and DNMT3A expression, and cell-cycle arrest. MATERIALS AND METHODS: The immunohistochemistry of DNMT1, DNMT3A, DNMT3B, Ki-67, and cyclin D1 was analyzed in 40 samples of MEC and 15 samples of healthy minor salivary glands. The effects of 5AC on DNMT1 and DNMT3B expression in MEC cell lines were analyzed by Western blot, and the effects of 5AC on the cell cycle were analyzed using flow cytometry. RESULTS: The expression of DNMT1 and DNMT3B was more intense in MECs than in healthy salivary glands. A strong correlation was found between the expression of the DNMTs and the proliferation markers. This correlation was validated In Vitro, where treatment with 5AC reduced the expression of the DNMTs and the percentage of cells at the G2/M phase of the cell cycle. CONCLUSION: The expression of DNMT1, DNMT3A, DNMT3B is correlated significantly with the expression of Ki-67 and cyclin D1. The treatment with 5AC reduces DNMT expression and decreases the percentage of cells at the G2/M phase of the cell cycle, while increasing the cells at the G0/G1 phase.


Assuntos
Carcinoma Mucoepidermoide , Proliferação de Células , DNA , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Humanos
15.
Transfus Apher Sci ; 59(2): 102720, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31980333

RESUMO

INTRODUCTION: Patients with RH variants presenting antibodies directed to RH high frequency antigens or multiple RH antibodies might, in some occasions, be better served with RH genotype-matched units, requiring screening for RH variants among blood donors. To date, strategies to identify donors with RH variants were restricted to selecting individuals of African descent based on self-reported race, what can be inaccurate in racially mixed population. Our goal was to: 1) Screen for donors with RH variants in a mixed population using self-declared race and Rh phenotype as selection criteria; and 2) Verify if including the Duffy null genotype in the screening algorithm increases its effectiveness. METHODS: Brazilian donors were included if self-declared as black and phenotyped as R0r or R1r. All individuals were genotyped for RHCE exons 1, 5, 6 and 7 and for the FY*B c.-67 T > C polymorphism in order to determine the Duffy null genotype. RHD variants were searched for in cases of altered RHCE. RESULTS: Among 2500 blood donors, 217 fulfilled the inclusion criteria and were enrolled. Fifty-three (24.4 %) had a predicted clinically relevant Rh phenotype (partial antigens or lack of high frequency antigens). Twelve donors (5.5 %) had a predicted RhCE phenotype lacking either hrB or hrS. Most cases with predicted lack of high frequency antigens (66.7 %) occurred in donors with the Duffy null genotype. CONCLUSION: Selecting donors based on self-declared race, Rh phenotype and Duffy null genotype is feasible and effective in identifying RH variants lacking Rh high frequency antigens among racially mixed donors.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Feminino , Humanos , Masculino
16.
J Oral Maxillofac Surg ; 78(11): 1942.e1-1942.e9, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768403

RESUMO

PURPOSE: In this study we aimed to compare the effects of photobiomodulation (PBM) and dexamethasone (DXM) on pain, swelling, and the quality-of-life (QOL) of patients submitted to buccal fat pad removal. PATIENTS AND METHODS: A total of 20 patients with pseudoherniation of buccal fat pad were included in the present study. The patients were divided randomly into 2 groups: the PBM group (660 nm, 100 mW, 6 seconds, 2 J/cm2) and the DXM group (4 mg every 8 hours for 3 days after the procedure). Pain levels were evaluated using a visual analog scale at days 2 and 4 after surgery, whereas the edema was evaluated by measuring the distance between 6 reference points: tragus, pogonion of the soft tissue, lateral eye commissure, the gonial angle, nose wing, and mouth commissure at days 2, 4, 7, 15, 30, 60, and 90. The QOL was evaluated using the Oral Health Impact Profile 14 questionnaire at days 2 and 4 after surgery. RESULTS: There were no differences between the PBM and DXM groups in pain or edema. In terms of the QOL, the PBM group was significantly more comfortable when chewing than the DXM group (P < .05) CONCLUSION: The use of PBM at a power of 100 mW and 2 J/cm2 per point had similar effects to oral DXM for the control of pain and edema, as well as in the QOL, except for masticatory function, which was significantly better in the PBM group.


Assuntos
Terapia com Luz de Baixa Intensidade , Boca , Qualidade de Vida , Tecido Adiposo/cirurgia , Dexametasona/uso terapêutico , Edema , Humanos , Boca/cirurgia , Dor
17.
Biochemistry ; 58(41): 4183-4194, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31566355

RESUMO

Cellular retinoic acid-binding protein 2 (CRABP2) delivers all-trans retinoic acid (atRA) to retinoic acid receptors (RARs), allowing for the activation of specific gene transcription. The structural similarities between free and atRA-bound CRABP2 raise the questions of how atRA binding occurs and how the atRA:CRABP2 complex is recognized by downstream binding partners. Thus, to gain insights into these questions, we conducted a detailed atRA-CRABP2 interaction study using nuclear magnetic resonance spectroscopy. The data showed that free CRABP2 displays widespread intermediate-time scale dynamics that is effectively suppressed upon atRA binding. This effect is mirrored by the fast-time scale dynamics of CRABP2. Unexpectedly, CRABP2 rigidification in response to atRA binding leads to the stabilization of a homodimerization interface, which encompasses residues located on helix α2 and the ßC-ßD loop as well as residues on strands ßI-ßA and the ßH-ßI loop. Critically, this rigidification also affects CRABP2's nuclear localization signal and RAR-binding motif, suggesting that the loss of conformational entropy upon atRA binding may be the key for the diverse cellular functions of CRABP2.


Assuntos
Multimerização Proteica , Receptores do Ácido Retinoico/química , Receptores do Ácido Retinoico/metabolismo , Tretinoína/química , Tretinoína/metabolismo , Núcleo Celular/metabolismo , Cristalização , Entropia , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligantes , Espectroscopia de Ressonância Magnética , Ligação Proteica , Estrutura Secundária de Proteína , Receptores do Ácido Retinoico/genética
18.
Biochemistry ; 58(20): 2488-2498, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31034208

RESUMO

Zika virus (ZIKV) became an important public health concern because infection was correlated to the development of microcephaly and other neurological disorders. Although the structure of the virion has been determined by cryo-electron microscopy, information about the nucleocapsid is lacking. We used nuclear magnetic resonance to determine the solution structure and dynamics of full length ZIKV capsid protein (ZIKVC). Although most of the protein is structured as described for the capsid proteins of Dengue and West Nile viruses and for truncated ZIKVC (residues 23-98), here we show important differences in the α-helix 1 and N-terminal intrinsically disordered region (IDR). We distinguished two dynamical regions in the ZIKVC IDR, a highly flexible N-terminal end and a transitional disordered region, indicating that it contains ordered segments rather than being completely flexible. The unique size and orientation of α-helix 1 partially occlude the protein hydrophobic cleft. Measurements of the dynamics of α-helix 1, surface exposure, and thermal susceptibility of each backbone amide 1H in protein structure revealed the occlusion of the hydrophobic cleft by α1/α1' and supported α-helix 1 positional uncertainty. On the basis of the findings described here, we propose that the dynamics of ZIKVC structural elements responds to a structure-driven regulation of interaction of the protein with intracellular hydrophobic interfaces, which would have an impact on the switches that are necessary for nucleocapsid assembly. Subtle differences in the sequence of α-helix 1 have an impact on its size and orientation and on the degree of exposure of the hydrophobic cleft, suggesting that α-helix 1 is a hot spot for evolutionary adaptation of the capsid proteins of flaviviruses.


Assuntos
Proteínas do Capsídeo/química , Capsídeo/química , Zika virus/química , Sequência de Aminoácidos , Interações Hidrofóbicas e Hidrofílicas , Proteínas Intrinsicamente Desordenadas/química , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica em alfa-Hélice , Domínios Proteicos , Alinhamento de Sequência
19.
J Cell Biochem ; 120(4): 5377-5385, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30320908

RESUMO

NSD3s, the proline-tryptophan-tryptophan-proline (PWWP) domain-containing, short isoform of the human oncoprotein NSD3, displays high transforming properties. Overexpression of human NSD3s or the yeast protein Pdp3 in Saccharomyces cerevisiae induces similar metabolic changes, including increased growth rate and sensitivity to oxidative stress, accompanied by decreased oxygen consumption. Here, we set out to elucidate the biochemical pathways leading to the observed metabolic phenotype by analyzing the alterations in yeast metabolome in response to NSD3s or Pdp3 overexpression using 1 H nuclear magnetic resonance (NMR) metabolomics. We observed an increase in aspartate and alanine, together with a decrease in arginine levels, on overexpression of NSD3s or Pdp3, suggesting an increase in the rate of glutaminolysis. In addition, certain metabolites, including glutamate, valine, and phosphocholine were either NSD3s or Pdp3 specific, indicating that additional metabolic pathways are adapted in a protein-dependent manner. The observation that certain metabolic pathways are differentially regulated by NSD3s and Pdp3 suggests that, despite the structural similarity between their PWWP domains, the two proteins act by unique mechanisms and may recruit different downstream signaling complexes. This study establishes for the first time a functional link between the human oncoprotein NSD3s and cancer metabolic reprogramming.


Assuntos
Histona Acetiltransferases/genética , Histona-Lisina N-Metiltransferase/genética , Metaboloma/genética , Proteínas Nucleares/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Alanina/genética , Ácido Aspártico/genética , Regulação da Expressão Gênica/genética , Humanos , Metabolômica/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Prolina/genética , Domínios Proteicos/genética , Transdução de Sinais/genética
20.
J Urol ; 201(2): 332-341, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30218760

RESUMO

PURPOSE: Conventional imaging cannot definitively detect nodal metastases of prostate cancer. We histologically validated C-acetate positron emission tomography/computerized tomography to identify nodal metastases, examining prostate cancer factors that influence detection rates. MATERIALS AND METHODS: Patients with C-acetate avid positron emission tomography/computerized tomography imaged pelvic/retroperitoneal lymph nodes underwent high extended robotic lymphadenectomy. A standardized mapping template comprising 8 predetermined anatomical regions was dissected during lymphadenectomy, allowing for matched, region based analysis and comparison of imaging and histological data. RESULTS: In 25 patients a total of 2,149 lymph nodes were excised (mean 86 per patient, range 27 to 136) and 528 (22%) harbored metastases (mean 21 positive nodes per patient, range 0 to 109). A total of 174 anatomical regions had matching imaging histological data. C-acetate positron emission tomography/computerized tomography accurately identified 48 node-positive regions and accurately ruled out 88 regions as metastasis-free. C-acetate sensitivity, specificity, and positive and negative predictive values were 67%, 84%, 74% and 79%, respectively. An increasing, histologically measured metastatic lesion size in long axis diameter of 5 or less, 6 to 10, 11 to 15, 16 to 20 and 21 mm or greater correlated with improved C-acetate detection rates of 45%, 62%, 81%, 89% and 100%, respectively. Each standard uptake value unit increase correlated with a 1.9 mm increase in nodal long axis diameter (p <0.001) and a 1.2 mm increase in short axis diameter (p <0.001). Positive C-acetate positron emission tomography/computerized tomography findings correlated with histological lymph node size (long axis diameter 12 mm and short axis diameter 6 mm), metastatic lesion size (long axis diameter 11 mm and short axis diameter 6 mm) and extranodal extension (positive 88% vs false-negative 58%, p = 0.005). CONCLUSIONS: C-acetate positron emission tomography/computerized tomography can identify prostate cancer metastatic nodal disease. However, it underestimates the true cephalad extent of nodal involvement, performing better in the pelvis than in the retroperitoneum. Standard uptake value, histological nodal size, intranodal metastasis size and extranodal extension correlate with cancer bearing nodes.


Assuntos
Radioisótopos de Carbono/administração & dosagem , Metástase Linfática/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos/administração & dosagem , Idoso , Reações Falso-Negativas , Humanos , Excisão de Linfonodo/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Pelve/diagnóstico por imagem , Estudos Prospectivos , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Espaço Retroperitoneal/diagnóstico por imagem , Procedimentos Cirúrgicos Robóticos/métodos , Sensibilidade e Especificidade
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