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1.
Neuroscience ; 549: 65-75, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38750924

RESUMO

Recent evidence has supported a pathogenic role for neuroinflammation in Parkinson's disease (PD). Inflammatory response has been associated with symptoms and subtypes of PD. However, it is unclear whether immune changes are involved in the initial pathogenesis of PD, leading to the non-motor symptoms (NMS) observed in its prodromal stage. The current study aimed to characterize the behavioral and cognitive changes in a toxin-induced model of prodromal PD-like syndrome. We also sought to investigate the role of neuroinflammation in prodromal PD-related NMS. Male mice were subjected to bilateral intranasal infusion with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or saline (control group), followed by comprehensive behavioral, pathological and neurochemical analysis. Intranasal MPTP infusion was able to cause the loss of dopaminergic neurons in the substantia nigra (SN). In parallel, it induced impairment in olfactory discrimination and social memory consolidation, compulsive and anxiety-like behaviors, but did not influence motor performance. Iba-1 and GFAP expressions were increased in the SN, suggesting an activated state of microglia and astrocytes. Consistent with this, MPTP mice had increased levels of IL-10 and IL-17A, and decreased levels of BDNF and TrkA mRNA in the SN. The striatum showed increased IL-17A, BDNF, and NFG levels compared to control mice. In conclusion, neuroinflammation may play an important role in the early stage of experimental PD-like syndrome, leading to cognitive and behavioral changes. Our results also indicate that intranasal administration of MPTP may represent a valuable mouse model for prodromal PD.

2.
J Biomol Struct Dyn ; 42(2): 687-695, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36995305

RESUMO

Metal encapsulation delivers a straightforward strategy to improve miscellaneous nanoparticle properties and qualifies the resulting nanocomposite for exceptional application, including bioimaging, drug release, and theranostic development. Besides crucial applications, investigations associated with the nanocomposite impact on the biological media are highly relevant from a pharmacological viewpoint. Such studies can be conducted by exploring nanocomposite attributes and all aspects of their interaction with proteins existing in biofluids. Based on these aspects, the present work examines manganese-encapsulated carbonaceous nanocomposite (MnCQD) and their interaction with plasma proteins. On one side, the obtained nanocomposite has almost spherical shapes (≈12 nm in size), an appropriate composition and interesting optical properties for bioimaging applications. On another side, MnCQD quenches the fluorescence of two plasma proteins (BSA and HTF) following a static mechanism, confirming the formation of the MnCQD-BSA and MnCQD-HTF complexes. Although hydrophobic forces guide the stability of both formed complexes, MnCQD binds preferentially to BSA compared to HTF, with affinity constants differing by almost an order of magnitude. Furthermore, HTF and BSA underwent modifications in their secondary structure provoked due to contact with the nanocomposite, which also presented neglectable opsonization levels when exposed to appropriate biological media. These results highlight the MnCQD outstanding potential to be employed in diverse bioapplications.Communicated by Ramaswamy H. Sarma.


Assuntos
Manganês , Nanocompostos , Opsonização , Fluorescência , Proteínas Sanguíneas , Nanocompostos/química , Soroalbumina Bovina/química , Ligação Proteica , Espectrometria de Fluorescência
3.
Differentiation ; 130: 43-50, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36608575

RESUMO

Tuberin is a member of a large protein complex, Tuberous Sclerosis Complex (TSC), and acts as a sensor for nutrient status regulating protein synthesis and cell cycle progression. Mutations in the Tuberin gene, TSC2, permits the formation of tumors that can lead to developmental defects in many organ systems, including the central nervous system. Tuberin is expressed in the brain throughout development and levels of Tuberin have been found to decrease during neuronal differentiation in cell lines in vitro. Our current work investigates the levels of Tuberin at two stages of embryonic development in vivo, and we study the mRNA and protein levels during a time course using immortalized cell lines in vitro. Our results show that total Tuberin levels are tightly regulated through developmental stages in the embryonic brain. At a cell biology level, we show that Tuberin levels are higher when cells are cultured as neurospheres, and knockdown of Tuberin results in a reduction in the number of neurospheres. This functional data supports the hypothesis that Tuberin is an important regulator of stemness and the reduction of Tuberin levels might support functional differentiation in the central nervous system. Understanding how Tuberin expression is regulated throughout neural development is essential to fully comprehend the role of this protein in several developmental and neural pathologies.


Assuntos
Proteínas Repressoras , Proteínas Supressoras de Tumor , Feminino , Humanos , Gravidez , Encéfalo/metabolismo , Encéfalo/patologia , Diferenciação Celular , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética
4.
Physiother Res Int ; 28(2): e1983, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36377222

RESUMO

BACKGROUND AND OBJECTIVES: Hospitalization by Covid-19 can cause persistent functional consequences after hospital discharge due to direct and indirect effects of SARS-COV-2 in several organs and systems of the body added to post-intensive care syndrome and prolonged bed rest. These impacts can lead to dependency in activities of daily living, mainly in older people due to aging process and functional decline. This study aimed to compare the effects of hospitalization by Covid-19 on functional capacity of adults and older people and to identify its associated factors. METHODS: Cross-sectional observational study of 159 survivors of hospitalization by Covid-19 after 1 month from discharge at Hospital das Clínicas of the University of São Paulo, divided into groups: adults (aged < 60 years) and older people (aged ≥ 60 years). Those who did not accept to participate, without availability or without ability to understand the questionnaires were excluded. Functional capacity was assessed by the Barthel Index and patients were classified according to their scores. Data analysis was performed in JASP Statistics program and the sample was compared between the age groups. Wilcoxon test was applied to compare before and after periods, Mann-Whitney test was used for between groups comparison. We adopted alpha = 0.05. RESULTS: The total Barthel Index median score was lower 1 month after hospital discharge than in the pre-Covid-19 period. Older people had worse functional status than adults before and also showed greater impairment after hospital discharge. Both groups showed lower Barthel Index classification than before, and older people presented more functional dependence than adults in both periods. Age, sarcopenia and frailty were associated factors. DISCUSSION: Hospitalization by Covid-19 impacts functional capacity after 1 month from discharge, especially in older people. Age, sarcopenia and frailty are associated factors. These results suggest need for care and rehabilitation of Covid-19 survivors.


Assuntos
COVID-19 , Fragilidade , Sarcopenia , Humanos , Adulto , Idoso , Atividades Cotidianas , Estudos Transversais , SARS-CoV-2 , Hospitalização
5.
PLoS One ; 17(8): e0272741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35947627

RESUMO

Tuberin is a major component of the protein regulatory complex known as the Tuberous Sclerosis Complex and plays a crucial role in cell cycle progression and protein synthesis. Mutations in the Tuberin gene, TSC2, lead to the formation of benign tumors in many organ systems and causes the Tuberous Sclerosis Complex disorder. Genotypes ranging from point mutations to large deletions in the TSC2 gene have been clinically characterized with a wide range of phenotypes from skin tumors to large brain tumors. Our lab has previously demonstrated that Tuberin can directly bind and regulate the timing of nuclear transport of the G2/M cyclin, Cyclin B1. Herein we study the consequence of one clinically relevant truncation in the Tuberin protein on cell cycle function. We demonstrate that exogenous expression of a fragment of the N-term region of Tuberin alters the subcellular localization of Cyclin B1 and increases cell proliferation. This adds to our body of information about the residues within Tuberin responsible for regulating the cytoplasmic retention of Cyclin B1 and supports the phenotypic data seen in the clinic with Tuberous Sclerosis Complex patients harbouring similar large deletions in Tuberin.


Assuntos
Esclerose Tuberosa , Ciclina B1/genética , Ciclinas , Humanos , Proteínas Repressoras/genética , Esclerose Tuberosa/patologia , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
6.
BMJ Open ; 12(7): e057246, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896292

RESUMO

OBJECTIVES: The study investigated the long-term functional status of hospitalised COVID-19 survivors to explore and document their functional situation. DESIGN: This prospective observational study assessed 801 COVID-19 survivors at 3-11 months after hospital discharge. It analyses participants' sociodemographic background, COVID-19 clinical manifestations, and clinical and functional evaluations. SETTING: Tertiary-level university hospital in São Paulo, Brazil. PARTICIPANTS: Study participants are COVID-19 survivors admitted to hospital care for at least 24 hours to treat acute SARS-CoV-2 infection. OUTCOME MEASURES: Epworth Sleepiness Scale, EuroQoL-5 Dimensions-5 Levels, Functional Assessment of Chronic Illness Therapy-Fatigue, Functional Independence Measure, Functional Oral Intake Scale, Handgrip Strength, Insomnia Severity Index, Medical Research Council (MRC) Dyspnea Scale, MRC sum score, Modified Borg Dyspnea Scale, pain Visual Analogue Scale, Post-COVID-19 Functional Status, Timed Up and Go, WHO Disability Assessment Schedule 2.0, 1-Minute Sit to Stand Test. RESULTS: Many participants required invasive mechanical ventilation (41.57%, 333 of 801). Mean age was 55.35±14.58 years. With a mean of 6.56 (SD: 1.58; 95% CI: 6.45 to 6.67) months after hospital discharge, 70.86% (567 of 800) reported limited daily activities, which were severe in 5.62% (45 of 800). They also reported pain and discomfort (64.50%, 516 of 800), breathlessness (64.66%, 514 of 795), and anxiety and depression (57.27%, 457 of 798). Daytime sleepiness and insomnia evaluations showed subthreshold results. Most (92.85%, 727 of 783) participants reported unrestricted oral intake. Data indicated no generalised fatigue (mean score: 39.18, SD: 9.77; 95% CI: 38.50 to 39.86). Assessments showed poor handgrip strength (52.20%, 379 of 726) and abnormal Timed Up and Go results (mean 13.07 s, SD: 6.49). The invasive mechanical ventilation group seemed to have a better handgrip strength however. We found no clear trends of change in their functional status during months passed since hospital discharge. CONCLUSIONS: Muscle weakness, pain, anxiety, depression, breathlessness, reduced mobility, insomnia and daytime sleepiness were the most prevalent long-term conditions identified among previously hospitalised COVID-19 survivors.


Assuntos
COVID-19 , Distúrbios do Sono por Sonolência Excessiva , Distúrbios do Início e da Manutenção do Sono , Adulto , Idoso , Brasil/epidemiologia , COVID-19/epidemiologia , COVID-19/terapia , Dispneia , Fadiga/epidemiologia , Fadiga/etiologia , Força da Mão , Hospitalização , Humanos , Pessoa de Meia-Idade , Dor , SARS-CoV-2 , Sobreviventes
7.
Stem Cells ; 39(12): 1688-1700, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34486784

RESUMO

Fully differentiated cells can be reprogrammed through ectopic expression of key transcription factors to create induced pluripotent stem cells. These cells share many characteristics of normal embryonic stem cells and have great promise in disease modeling and regenerative medicine. The process of remodeling has its limitations, including a very low efficiency due to the upregulation of many antiproliferative genes, including cyclin dependent kinase inhibitors CDKN1A and CDKN2A, which serve to protect the cell by inducing apoptotic and senescent programs. Our data reveals a unique cell cycle mechanism enabling mouse fibroblasts to repress cyclin dependent kinase inhibitors through the activation of the epigenetic regulator EZH2 by a cyclin-like protein SPY1. This data reveals that the SPY1 protein is required for reprogramming to a pluripotent state and is capable of increasing reprogramming efficiency.


Assuntos
Histonas , Células-Tronco Pluripotentes Induzidas , Animais , Reprogramação Celular/genética , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Células-Tronco Embrionárias/metabolismo , Fibroblastos/metabolismo , Histonas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos
8.
Clin Infect Dis ; 72(11): e736-e741, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32964918

RESUMO

BACKGROUND: A local increase in angiotensin 2 after inactivation of angiotensin-converting enzyme 2 by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce a redox imbalance in alveolar epithelium cells, causing apoptosis, increased inflammation and, consequently, impaired gas exchange. We hypothesized that N-acetylcysteine (NAC) administration could restore this redox homeostasis and suppress unfavorable evolution in patients with coronavirus disease 2019 (COVID-19). METHODS: This was a double-blind, randomized, placebo-controlled, single-center trial conducted at the Emergency Department of Hospital das Clínicas, São Paulo, Brazil, to determine whether NAC in high doses can avoid respiratory failure in patients with COVID-19. We enrolled 135 patients with severe COVID-19 (confirmed or suspected), with an oxyhemoglobin saturation <94% or respiratory rate >24 breaths/minute. Patients were randomized to receive NAC 21 g (~300 mg/kg) for 20 hours or dextrose 5%. The primary endpoint was the need for mechanical ventilation. Secondary endpoints were time of mechanical ventilation, admission to the intensive care unit (ICU), time in ICU, and mortality. RESULTS: Baseline characteristics were similar between the 2 groups, with no significant differences in age, sex, comorbidities, medicines taken, and disease severity. Also, groups were similar in laboratory tests and chest computed tomography scan findings. Sixteen patients (23.9%) in the placebo group received endotracheal intubation and mechanical ventilation, compared with 14 patients (20.6%) in the NAC group (P = .675). No difference was observed in secondary endpoints. CONCLUSIONS: Administration of NAC in high doses did not affect the evolution of severe COVID-19. CLINICAL TRIALS REGISTRATION: Brazilian Registry of Clinical Trials (REBEC): U1111-1250-356 (http://www.ensaiosclinicos.gov.br/rg/RBR-8969zg/).


Assuntos
Tratamento Farmacológico da COVID-19 , Acetilcisteína/uso terapêutico , Brasil , Método Duplo-Cego , Humanos , Respiração Artificial , SARS-CoV-2 , Resultado do Tratamento
9.
PLoS One ; 14(1): e0210612, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30629673

RESUMO

A great deal of ground breaking work has determined that the Tuberin and Hamartin Complex function as a negative regulator of protein synthesis and cell cycle progression through G1/S. This is largely attributed to the GTPase activity of Tuberin that indirectly inhibits the mammalian target of rapamycin (mTOR). During times of ample nutrition Tuberin is inhibited by growth factor signaling, including direct phosphorylation by Akt/PKB, allowing for activation of mTOR and subsequent protein synthesis. It is well rationalized that maintaining homeostasis requires communication between cell growth (mTOR signaling) and cell division (cell cycle regulation), however how this occurs mechanistically has not been resolved. This work demonstrates that in the presence of high serum, and/or Akt signaling, direct binding between Tuberin and the G2/M cyclin, Cyclin B1, is stabilized and the rate of mitotic entry is decreased. Importantly, we show that this results in an increase in cell size. We propose that this represents a novel cell cycle checkpoint linking mitotic onset with the nutritional status of the cell to control cell growth.


Assuntos
Ciclina B1/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Pontos de Checagem da Fase M do Ciclo Celular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Células HEK293 , Humanos , Mitose , Mapas de Interação de Proteínas , Soro/metabolismo
10.
PLoS One ; 13(10): e0204477, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30303980

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is associated with an increased risk of hepatitis B infection and impaired seroconversion to hepatitis B vaccine (HBV). Studies examining augmented vaccine schedules to enhance seroconversion have so far been inconclusive. Furthermore, the defects responsible for impaired vaccine immunity in CKD have not yet been identified. METHODS: We studied serological and cellular responses to HBV in CKD to identify a defect in vaccine-induced cellular responses that could account for impaired seroconversion in CKD and clarify the effects of an augmented vaccine dose schedule. We compared these results with responses to seasonal influenza vaccination (Fluvax). RESULTS: We found a clear benefit in rates and magnitude of seroconversion after an augmented 40mcg HBV dose schedule in CKD. This permitted comparison of responders and non-responders. Serological non-responders with CKD exhibited reduction in CXCR3+CCR6- CXCR5+ memory T cells at baseline. Unlike Fluvax, HBV elicited a poor plasmablast (PB) response. Both vaccinations induced activation of the CXCR3+CCR6- CCR7- subset of circulating T follicular helper cells (cTFH), although this response was impaired in CKD after HBV. CONCLUSIONS: CKD confers a specific T cell defect that contributes to the impaired seroconversion to HBV.


Assuntos
Vacinas contra Hepatite B , Insuficiência Renal Crônica/imunologia , Vacinação , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Vacinas contra Hepatite B/administração & dosagem , Humanos , Vacinas contra Influenza , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Soroconversão , Linfócitos T/imunologia , Vacinação/métodos , Adulto Jovem
11.
J Exp Med ; 215(11): 2715-2724, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30337470

RESUMO

Genetic mutations account for many devastating early onset immune deficiencies. In contrast, less severe and later onset immune diseases, including in patients with no prior family history, remain poorly understood. Whole exome sequencing in two cohorts of such patients identified a novel heterozygous de novo IKBKB missense mutation (c.607G>A) in two separate kindreds in whom probands presented with immune dysregulation, combined T and B cell deficiency, inflammation, and epithelial defects. IKBKB encodes IKK2, which activates NF-κB signaling. IKK2V203I results in enhanced NF-κB signaling, as well as T and B cell functional defects. IKK2V203 is a highly conserved residue, and to prove causation, we generated an accurate mouse model by introducing the precise orthologous codon change in Ikbkb using CRISPR/Cas9. Mice and humans carrying this missense mutation exhibit remarkably similar cellular and biochemical phenotypes. Accurate mouse models engineered by CRISPR/Cas9 can help characterize novel syndromes arising from de novo germline mutations and yield insight into pathogenesis.


Assuntos
Mutação com Ganho de Função , Heterozigoto , Quinase I-kappa B/imunologia , Síndromes de Imunodeficiência/imunologia , Substituição de Aminoácidos , Animais , Estudos de Coortes , Feminino , Humanos , Quinase I-kappa B/genética , Síndromes de Imunodeficiência/genética , Masculino , Camundongos , Camundongos Mutantes , Sequenciamento Completo do Genoma
12.
Mult Scler Relat Disord ; 25: 87-94, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30056361

RESUMO

OBJECTIVE: Antibodies against Myelin Oligodendrocyte glycoprotein (MOG-Ab) have been investigated as potential biological marker for neuromyelitis optica (NMO) and high-risk syndromes (HR) negative for AQP4-Ab in populations with different ethnic background. We tested AQP4 and MOG antibodies in a Brazilian population with high African ethnic background. METHOD: The study population was composed of adult patients from Rio de Janeiro with inflammatory demyelinating diseases (new and old cases). Blood samples were sent blindly to test the AQP4 and MOG antibodies by CBA. The frequency of positive MOG-Ab was estimated in the NMOHR and the NMO spectrum disorders (NMOSD). A systematic review with meta-analysis assessed the frequency of MOG-Ab in Caucasians and non-Caucasians. RESULTS: 200 adult patients (52% Afro-Brazilian) 115 of them with NMOHR were tested. MOG antibodies were found in 5/68 negative cases of AQP4-Ab negative (7%). The criteria for NMOSD were fulfilled by 70 patients with NMOHR and none of them was positive for MOG-Ab. A low prevalence of MOG antibodies and a predominant phenotype of bilateral Optic Neuritis were found in most non-Caucasian patients. CONCLUSION: The low frequency of MOG Ab in patients from Rio de Janeiro and in other non-Caucasian populations suggests a racial/ancestral influence.


Assuntos
Autoanticorpos/sangue , Doenças Desmielinizantes/sangue , Doenças Desmielinizantes/etnologia , Etnicidade , Glicoproteína Mielina-Oligodendrócito/imunologia , Adolescente , Adulto , Idoso , Aquaporina 4/imunologia , Brasil/etnologia , Criança , Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/epidemiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estatísticas não Paramétricas , Adulto Jovem
13.
PLoS One ; 13(4): e0195574, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29702684

RESUMO

INTRODUCTION: Transrectal ultrasound-guided biopsy (TUSPB) is the standard method of diagnosis for prostate cancer, and although it is well tolerated by some patients, it presents a discomfort rate of 65 to 90%, which may be associated with pain. For convenience, it is agreed that a method of analgesia and sedation is necessary. For this purpose, this study aimed to evaluate the impact of inhalation of a 50-50% N2O-O2 gas mixture on pain intensity in these patients. MATERIAL AND METHODS: Randomized, double-blinded clinical trial, conducted at Antônio Pedro University Hospital (Hospital Universitário Antônio Pedro), Niterói, RJ, Brazil, containing two groups of 42 patients: a control (C) group, which received 100% oxygen inhalation, and a nitrous oxide (NO) group, which received inhalation of the 50-50% N2O-O2 mixture, self-administered during TUSPB. The pain intensity and degree of satisfaction were evaluated through a visual analogue scale (VAS), as was the frequency of adverse events. RESULTS: Eighty-four patients were included in the study, with 42 in each group. The mean pain intensity was lower in the NO group than in the C group [2.52 (0-10) vs 5.95 (0-10), p < 0.001], and the degree of satisfaction was higher in the NO group than in the C group (8.14 vs. 4.69, p < 0.001). The adverse effects were somnolence, dizziness, nausea, vomiting, discomfort and euphoria without differences between the groups. CONCLUSION: The 50-50% N2O-O2 mixture was effective in reducing pain intensity and increasing the degree of satisfaction in TUSPB, with tolerable side effects.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Biópsia Guiada por Imagem , Óxido Nitroso/uso terapêutico , Oxigênio/uso terapêutico , Dor Processual/tratamento farmacológico , Próstata/cirurgia , Administração por Inalação , Idoso , Idoso de 80 Anos ou mais , Analgésicos não Narcóticos/efeitos adversos , Método Duplo-Cego , Gases/efeitos adversos , Gases/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nitroso/efeitos adversos , Oxigênio/efeitos adversos , Medição da Dor , Satisfação do Paciente , Próstata/diagnóstico por imagem , Próstata/patologia , Reto/diagnóstico por imagem , Reto/cirurgia , Resultado do Tratamento , Ultrassonografia de Intervenção
14.
Biointerphases ; 13(3): 03B406, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402092

RESUMO

The iridescent wings of the Chalcopterix rutilans damselfly (Rambur) (Odonata, Polythoridae) are investigated with focused ion beam/scanning electron microscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry. The electron microscopy images reveal a natural photonic crystal as the source of the varying colors. The photonic crystal has a consistent number and thickness (∼195 nm) of the repeat units on the ventral side of the wing, which is consistent with the red color visible from the bottom side of the wing in all regions. The dorsal side of the wing shows strong color variations ranging from red to blue depending on the region. In the electron microscopy images, the dorsal side of the wing exhibits varied number and thicknesses of the repeat units. The repeat unit spacings for the red, yellow/green, and blue regions are approximately 195, 180, and 145 nm, respectively. Three-dimensional analysis of the natural photonic crystals by time-of-flight secondary ion mass spectrometry reveals that changes in the relative levels of Na, K, and eumelanin are responsible for the varying dielectric constant needed to generate the photonic crystal. The photonic crystal also appears to be assembled with a chemical tricomponent layer structure due to the enhancement of the CH6N3+ species at every other interface between the high/low dielectric constant layers.


Assuntos
Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Odonatos/química , Odonatos/ultraestrutura , Espectrometria de Massa de Íon Secundário , Asas de Animais/química , Asas de Animais/ultraestrutura , Animais , Iridescência , Melaninas/análise , Potássio/análise , Sódio/análise
15.
Curr Drug Deliv ; 15(7): 1064-1071, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29318970

RESUMO

BACKGROUND: PnPP-19 is a 19-amino-acid synthetic peptide previously described as a novel drug for the treatment of erectile dysfunction. OBJECTIVE: The aim of this work was to evaluate the physicochemical properties of cationic transfersomes containing PnPP-19 and the skin permeation of free PnPP-19 and PnPP-19-loaded transfersomes. METHODS: Three different liposomal preparation methods were evaluated. Cationic transfersomes contained egg phosphatidyl choline: stearylamine (9:1 w/w) and Tween 20 (84.6:15.4 lipid:Tween, w/w). Lipid concentration varied from 20 to 40 mM. We evaluated the entrapment percentage, mean diameter, zeta potential and stability at 4 °C of the formulations. The skin permeation assays were performed with abdominal human skin using Franz diffusion cell with 3 cm2 diffusion area at 32 °C and a fluorescent derivative of the peptide, containing 5-TAMRA, bound to PnPP-19 C-terminal region, where an extra lysine was inserted. RESULTS: Our results showed variable entrapment efficiencies, from 6% to 30%, depending on the preparation method and the lipid concentration used. The reverse phase evaporation method using a total lipid concentration equal to 40 mM led to the best entrapment percentage (30.2 + 4.5%). Free PnPP-19 was able to permeate skin at a rate of 10.8 ng/cm2/h. However, PnPP-19 was specifically hydrolyzed by skin proteases, generating a fragment of 15 amino acid residues. Encapsulated PnPP-19 permeated the skin at a rate of 19.8 ng/cm2/h. CONCLUSION: The encapsulation of PnPP-19 in cationic transfersomes protected the peptide from degradation, favoring its topical administration.


Assuntos
Peptídeos/administração & dosagem , Peptídeos/química , Absorção Cutânea , Administração Cutânea , Adulto , Aminas/administração & dosagem , Aminas/química , Disfunção Erétil/tratamento farmacológico , Feminino , Humanos , Técnicas In Vitro , Lipossomos , Masculino , Pessoa de Meia-Idade , Fosfatidilcolinas/administração & dosagem , Fosfatidilcolinas/química , Polissorbatos/administração & dosagem , Polissorbatos/química , Rodaminas/administração & dosagem , Rodaminas/química , Pele/metabolismo
16.
Cytotechnology ; 68(1): 19-24, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24981314

RESUMO

Progression through G2 phase of the cell cycle is a technically difficult area of cell biology to study due to the lack of physical markers specific to this phase. The FUCCI system uses the biology of the cell cycle to drive fluorescence in select phases of the cell cycle. Similarly, a commercially available system has used a fluorescent analog of the Cyclin B1 protein to visualize cells from late S phase to the metaphase-anaphase transition. We have modified these systems to use the promoter and destruction box elements of Cyclin B1 to drive a cyan fluorescent protein. We demonstrate here that this is a useful tool for measuring the length of G2 phase without perturbing any aspect of cell cycle progression.

17.
Artigo em Português | LILACS | ID: lil-737313

RESUMO

Analisar os medicamentos das lactantes em tratamento na rede pública de saúde e as ações envolvidas. Métodos: Estudo transversal, quantitativo e descritivo realizado com 100 lactantes selecionadas através de amostragem não probabilística e por conveniência no Hospital Municipal de Duque de Caxias-RJ, no ano de 2012. Aplicou-se um questionário contendo as seguintes variáveis: informações sociodemográficas, medicamentos prescritos, efeitos indesejados nos lactentes, e profissionais envolvidos nas orientações quanto ao uso desses medicamentos. Analisaram-se os dados através da estatística descritiva, a partir de frequências absolutas e relativas. Resultados: Identificou-se que 46% (n=46) das lactantes tinham entre 21 e 30 anos, 54% (n=54) eram primíparas, 52% (n=52) tinham ensino fundamental completo e 72% (n=72) receberam o acompanhamento pré-natal. Verificouse que 78% (n=78) faziam uso de algum tipo de medicamento, dentre eles, um percentual significativo de analgésicos/anti-inflamatórios não esteroidais, com 61,54% (n=48) das lactantes. Todos os medicamentos prescritos estavam na categoria de uso compatível com a amamentação. Constatou-se presença de sintomas indesejados em 19,2% das lactantes (n=15). Das lactantes em terapia medicamentosa, 76,92 % (n=60) tiveram orientação durante o tratamento, sendo 55% (n= 33) por médicos e 45% (n=27) por enfermeiros. Nesta pesquisa, 100% das lactantes ficaram satisfeitas com o aprendizado. Conclusão: Observou-se número elevado de lactantes da amostra fazendo uso de medicamentos, todos compatíveis com a amamentação. Ressalta-se a participação restrita da equipe multidisciplinar nas orientações...


To analyse the medications used by breastfeeding women treated in the public health network, and correlated actions. Methods: Cross-sectional, quantitative and descriptive study carried out with 100 breastfeeding women, recruited through nonprobabilistic convenience sampling, at the Municipal Hospital of Duque de Caxias, RJ, in 2012. A questionnaire was applied containing the following variables: prescribedmedications, unwanted effects in nursing infants, and professionals involved in guidance on the edication. The data was analysed through descriptive statistics, based on absolute and relative frequencies. Results: It was found that 46% (n=46) of the breastfeeding women were aged 21 to 30 years, 54% (n=54) were primiparae, 52% (n=52) had complete fundamental level, and 72% (n=72) received prenatal care. It was verified that 78% (n = 78) of the sample were receiving some type of medicine and, among these, a significant percentage of nonsteroidal analgesic/anti-inflammatory medication, with 61.54% (n=48) of the breastfeeding women. All the prescribed medicines were in the category of compatible use with breastfeeding. The incidence of some unwanted symptoms was evidenced in 19.2% (n=15) of the breastfeeding women. Among the women undergoing medication therapy, 76.92% (n=60) received guidance during treatment, 55% (n=33) by doctors and 45% (n=27) by nurses. In this research, 100% of the breastfeeding women were satisfied with the acquired knowledge. Conclusion: It was noted a high percentage of breastfeeding women in the sample taking medicines, all compatible with breastfeeding. It stands out the limited engagement of the multidisciplinary team in the orientations...


Analizar los medicamentos de las lactantes asistidas en la red pública de salud y las acciones involucradas. Métodos: Estudio transversal, cuantitativo y descriptivo con 100 lactantes seleccionadas a través de muestreo no probabilístico y por conveniencia en el Hospital Municipal de Duque de Caxias-RJ en el año de 2012. Se aplico un cuestionario con las siguientes variables: informaciones sociodemograficas, medicamento prescrito, efectos no deseados en las lactantes y profesionales involucrados con las orientaciones sobre el uso de estos medicamentos. Los datos fueron analizados a través de estadística descriptiva a partir de frecuencias absolutas y relativas. Resultados: Se identifico que el 46% (n=46) de las lactantes tenían entre 21 y 30 años, el 54% (n=54) eran primíparas, el 52% (n=46) tenían la educación secundaria completa y el 72% (n=72) realizaron el prenatal. Se verifico que el 78% (n=78) usaban algún tipo de medicamento, entre ellos, un porcentaje significativo de analgésicos/antiinflamatorios no esteroideo en el 61,54% (n=48) de las lactantes. Todos los medicamentos prescritos eran de uso compatible con la lactancia. Se constató la presencia de sintomas no deseados en el 19,2% (n=15) de las lactantes. De las que estaban en terapia medicamentosa el 76,92 % (n=60) tuvieron orientación durante el tratamiento siendo el 55% (n= 33) por médicos y el 45% (n=27) por enfermeros. En esta investigación El 100% de las lactantes se quedaron satisfechas con el aprendizaje. Conclusión: Se observó un elevado número de lactantes de La muestra en terapia medicamentosa compatible con la lactancia. Se destaca la participación restricta del equipo multidisciplinario en las orientaciones...


Assuntos
Humanos , Aleitamento Materno , Tratamento Farmacológico , Sistema Único de Saúde
18.
Cancer Cell ; 25(1): 64-76, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24434210

RESUMO

The heterogeneity of brain cancers, as most solid tumors, complicates diagnosis and treatment. Identifying and targeting populations of cells driving tumorigenesis is a top priority for the cancer biology field. This is not a trivial task; considerable variance exists in the driving mutations, identifying markers, and evolutionary pressures influencing initiating cells in different individual tumors. Despite this, the ability to self-renew and differentiate must be conserved to reseed a heterogeneous tumor mass. Focusing on one example of a tumor-initiating cell population, we demonstrate that the atypical cyclin-like protein Spy1 plays a role in balancing the division properties of glioma cells with stemness properties. This mechanistic insight may provide new opportunities for therapeutic intervention of brain cancer.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Encefálicas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133 , Animais , Antígenos CD/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proteínas de Ciclo Celular/genética , Divisão Celular , Glioma/genética , Glioma/patologia , Glicoproteínas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microdissecção , Células-Tronco Neurais/metabolismo , Peptídeos/metabolismo , Prognóstico , Análise Serial de Tecidos
20.
Oecologia ; 172(2): 469-76, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23129400

RESUMO

Animal-pollinated invasive species have frequently been demonstrated to outcompete native species for pollinator attention, which can have detrimental effects on the reproductive success and population dynamics of native species. Many animal-pollinated invasive species exhibit showy flowers and provide substantial rewards, allowing them to act as pollinator 'magnets', which, at a large scale, can attract more pollinators to an area, but, at a smaller scale, may reduce compatible pollen flow to local native species, possibly explaining why most studies detect competition. By performing pollen limitation experiments of populations in both invaded and uninvaded sites, we demonstrate that the invasive plant Lythrum salicaria appears to facilitate, rather than hinder, the reproductive success of native confamilial Decodon verticillatus, even at a small scale, in a wetland habitat in southeastern Ontario. We found no evidence for a magnet species effect on pollinator attraction to invaded sites. Germination experiments confirmed that seeds from invaded sites had similar germination rates to those from uninvaded sites, making it unlikely that a difference in inbreeding was masking competitive effects. We describe several explanations for our findings. Notably, there were no differences in seed set among populations at invaded and uninvaded sites. Our results underscore the inherent complexity of studying the ecological impacts of invasive species on natives.


Assuntos
Espécies Introduzidas , Lythraceae/fisiologia , Lythrum/fisiologia , Pólen , Animais , Ecossistema , Germinação , Ontário , Polinização , Sementes/fisiologia , Especificidade da Espécie
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