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1.
Curr Opin Oncol ; 35(5): 420-425, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37551948

RESUMO

PURPOSE OF REVIEW: Gynecological cancer is a very important cause of comorbidity and mortality in women. The current delay in motherhood is increasing the incidence of women under 40 years of age that have not yet achieved their maternity goals when they are diagnosed and standard treatment negatively impacts the reproductive potential of cancer survivors. In this review, we update the information available about the safety of fertility-sparing treatments in young gynecological cancer patients, as well as the safety and efficacy of assisted reproductive techniques (ART) in such group. We also evaluate the long-term gynecological cancer risk in women requiring ART. RECENT FINDINGS: Although eligibility criteria continue to be very strict, there are more and more reports of fertility-sparing approaches outside of what traditionally has been considered safe. Molecular assessment is starting to be used in the selection of appropriate candidates. Data increasingly shows the long term safety and the efficacy of ART and pregnancy in these patients. SUMMARY: Appropriate selection is key to safely preconize fertility-sparing alternatives. Because subfertility may be a result of these procedures, ART could be indicated in this setting. Neither ART nor pregnancy appear to increase recurrences or affect survival rates.


Assuntos
Sobreviventes de Câncer , Neoplasias , Gravidez , Humanos , Feminino , Técnicas de Reprodução Assistida/efeitos adversos , Neoplasias/terapia
2.
Appl Environ Microbiol ; 88(12): e0057422, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35638842

RESUMO

Thirty peptide conjugates were designed by combining an antimicrobial peptide (BP16, BP100, BP143, KSL-W, BP387, or BP475) at the N- or C-terminus of a plant defense elicitor peptide (flg15, BP13, Pep13, or PIP1). These conjugates were highly active in vitro against six plant-pathogenic bacteria, especially against Xanthomonas arboricola pv. pruni, Xanthomonas fragariae and Xanthomonas axonopodis pv. vesicatoria. The most active peptides were those incorporating Pep13. The order of the conjugation influenced the antibacterial activity and the hemolysis. Regarding the former, peptide conjugates incorporating the elicitor peptide flg15 or Pep13 at the C-terminus were, in general, more active against Pseudomonas syringae pv. actinidiae and P. syringae pv. syringae, whereas those bearing these elicitor peptides at the N-terminus displayed higher activity against Erwinia. amylovora and the Xanthomonas species. The best peptide conjugates displayed MIC values between 0.8 and 12.5 µM against all the bacteria tested and also had low levels of hemolysis and low phytotoxicity. Analysis of the structural and physicochemical parameters revealed that a positive charge ranging from +5 to +7 and a moderate hydrophobic moment/amphipathic character is required for an optimal biological profile. Interestingly, flg15-BP475 exhibited a dual activity, causing the upregulation of the same genes as flg15 and reducing the severity of bacterial spot in tomato plants with a similar or even higher efficacy than copper oxychloride. Characterization by nuclear magnetic resonance (NMR) of the secondary structure of flg15-BP475 showed that residues 10 to 25 fold into an α-helix. This study establishes trends to design new bifunctional peptides useful against plant diseases caused by plant-pathogenic bacteria. IMPORTANCE The consequences of plant pathogens on crop production together with the lack of effective and environmentally friendly pesticides evidence the need of new agents to control plant diseases. Antimicrobial and plant defense elicitor peptides have emerged as good candidates to tackle this problem. This study focused on combining these two types of peptides into a single conjugate with the aim to potentiate the activity of the individual fragments. Differences in the biological activity of the resulting peptide conjugates were obtained depending on their charge, amphipathicity, and hydrophobicity, as well as on the order of the conjugation of the monomers. This work provided bifunctional peptide conjugates able to inhibit several plant-pathogenic bacteria, to stimulate plant defense responses, and to reduce the severity of bacterial spot in tomato plants. Thus, this study could serve as the basis for the development of new antibacterial/plant defense elicitor peptides to control bacterial plant pathogens.


Assuntos
Erwinia amylovora , Solanum lycopersicum , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Hemólise , Peptídeos/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Plantas/microbiologia , Xanthomonas
3.
Chemistry ; 27(48): 12395-12409, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34213045

RESUMO

Midkine (MK) is a neurotrophic factor that participates in the embryonic central nervous system (CNS) development and neural stem cell regulation, interacting with sulfated glycosaminoglycans (GAGs). Chondroitin sulfate (CS) is the natural ligand in the CNS. In this work, we describe the interactions between a library of synthetic models of CS-types and mimics. We did a structural study of this library by NMR and MD (Molecular Dynamics), concluding that the basic shape is controlled by similar geometry of the glycosidic linkages. Their 3D structures are a helix with four residues per turn, almost linear. We have studied the tetrasaccharide-midkine complexes by ligand observed NMR techniques and concluded that the shape of the ligands does not change upon binding. The ligand orientation into the complex is very variable. It is placed inside the central cavity of MK formed by the two structured beta-sheets domains linked by an intrinsically disordered region (IDR). Docking analysis confirmed the participation of aromatics residues from MK completed with electrostatic interactions. Finally, we test the biological activity by increasing the MK expression using CS tetrasaccharides and their capacity in enhancing the growth stimulation effect of MK in NIH3T3 cells.


Assuntos
Sulfatos de Condroitina , Oligossacarídeos , Animais , Glicosaminoglicanos , Camundongos , Midkina , Células NIH 3T3
4.
Int J Mol Sci ; 22(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205705

RESUMO

From a previous collection of lipopeptides derived from BP100, we selected 18 sequences in order to improve their biological profile. In particular, analogues containing a D-amino acid at position 4 were designed, prepared, and tested against plant pathogenic bacteria and fungi. The biological activity of these sequences was compared with that of the corresponding parent lipopeptides with all L-amino acids. In addition, the influence of the length of the hydrophobic chain on the biological activity was evaluated. Interestingly, the incorporation of a D-amino acid into lipopeptides bearing a butanoyl or a hexanoyl chain led to less hemolytic sequences and, in general, that were as active or more active than the corresponding all L-lipopeptides. The best lipopeptides were BP475 and BP485, both incorporating a D-Phe at position 4 and a butanoyl group, with MIC values between 0.8 and 6.2 µM, low hemolysis (0 and 24% at 250 µM, respectively), and low phytotoxicity. Characterization by NMR of the secondary structure of BP475 revealed that the D-Phe at position 4 disrupts the α-helix and that residues 6 to 10 are able to fold in an α-helix. This secondary structure would be responsible for the high antimicrobial activity and low hemolysis of this lipopeptide.


Assuntos
Anti-Infecciosos/síntese química , Lipopeptídeos/síntese química , Testes de Sensibilidade Microbiana , Oligopeptídeos/química , Doenças das Plantas/terapia , Doenças das Plantas/microbiologia
5.
Am J Pathol ; 187(6): 1426-1435, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28432873

RESUMO

The brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein (BMAL)-1 constitutes a major transcriptional regulator of the circadian clock. Here, we explored the impact of conditional deletion of Bmal1 in endothelium and hematopoietic cells in murine models of microvascular and macrovascular injury. We used two models of Bmal1fx/fx;Tek-Cre mice, a retinal ischemia/reperfusion model and a neointimal hyperplasia model of the femoral artery. Eyes were enumerated for acellular capillaries and were stained for oxidative damage markers using nitrotyrosine immunohistochemistry. LSK (lineage-negative, stem cell antigen-1-positive, c-Kit-positive) cells were quantified and proliferation assessed. Hematopoiesis is influenced by innervation to the bone marrow, which we assessed using IHC analysis. The number of acellular capillaries increased threefold, and nitrotyrosine staining increased 1.5-fold, in the retinas of Bmal1fx/fx;Tek-Cre mice. The number of LSK cells from the Bmal1fx/fx;Tek-Cre mice decreased by 1.5-fold and was accompanied by a profound decrease in proliferative potential. Bmal1fx/fx;Tek-Cre mice also exhibited evidence of bone marrow denervation, demonstrating a loss of neurofilament-200 staining. Injured femoral arteries showed a 20% increase in neointimal hyperplasia compared with similarly injured wild-type controls. Our study highlights the importance of the circadian clock in maintaining vascular homeostasis and demonstrates that specific deletion of BMAL1 in endothelial and hematopoietic cells results in phenotypic features similar to those of diabetes.


Assuntos
Fatores de Transcrição ARNTL/fisiologia , Neointima/patologia , Traumatismo por Reperfusão/metabolismo , Vasos Retinianos/metabolismo , Fatores de Transcrição ARNTL/deficiência , Fatores de Transcrição ARNTL/genética , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Capilares/patologia , Proliferação de Células , Ritmo Circadiano/fisiologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Artéria Femoral/lesões , Artéria Femoral/patologia , Deleção de Genes , Células-Tronco Hematopoéticas/patologia , Hiperplasia , Antígenos Comuns de Leucócito/análise , Contagem de Leucócitos , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/patologia , Retina/metabolismo , Vasos Retinianos/patologia
6.
Biophys J ; 112(7): 1366-1373, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28402879

RESUMO

The Achaete-scute homolog 1 (Ascl1) protein regulates a large subset of genes that leads neuronal progenitor cells to distinctive differentiation pathways during human brain development. Although it is well known that Ascl1 binds DNA as a homo- or heterodimer via its basic helix-loop-helix (bHLH) motif, little is known about the conformational sampling properties of the DNA-free full-length protein, and in particular about the bHLH domain-flanking N- and C-terminal segments, which are predicted to be highly disordered in solution. The structural heterogeneity, low solubility, and high aggregation propensity of Ascl1 in aqueous buffer solutions make high-resolution studies of this protein a challenging task. Here, we have adopted a fragment-based strategy that allowed us to obtain high-quality NMR data providing, to our knowledge, the first comprehensive high-resolution information on the structural propensities and conformational dynamics of Ascl1. The emerging picture is that of an overall extended and highly dynamic polypeptide chain comprising three helical segments and lacking persistent long-range interactions. We also show that the C-terminal helix of the bHLH domain is involved in intermolecular interactions, even in the absence of DNA. Our results contribute to a better understanding of the mechanisms of action that govern the regulation of proneural transcription factors.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Espectroscopia de Ressonância Magnética , Sequência de Aminoácidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , DNA/metabolismo , Humanos , Domínios Proteicos
7.
J Am Chem Soc ; 139(3): 1065-1068, 2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28067496

RESUMO

NMR spectroscopy is a powerful tool for studying molecular dynamics at atomic resolution simultaneously for a large number of nuclear sites. In this communication, we combine two powerful NMR techniques, relaxation-dispersion NMR and real-time NMR, in order to obtain unprecedented information on the conformational exchange dynamics present in short-lived excited protein states, such as those transiently accumulated during protein folding. We demonstrate the feasibility of the approach for the amyloidogenic protein ß2-microglobulin that folds via an intermediate state which is believed to be responsible for the onset of the aggregation process leading to amyloid formation.


Assuntos
Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Microglobulina beta-2/química , Humanos , Conformação Proteica , Dobramento de Proteína , Fatores de Tempo
8.
Am J Pathol ; 186(6): 1688-700, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27178803

RESUMO

Angiotensin-converting enzyme (ACE)-2 is the primary enzyme of the vasoprotective axis of the renin angiotensin system that regulates the classic renin angiotensin system axis. We aimed to determine whether local retinal overexpression of adenoassociated virus (AAV)-ACE2 prevents or reverses diabetic retinopathy. Green fluorescent protein (GFP)-chimeric mice were generated to distinguish resident (retinal) from infiltrating bone marrow-derived inflammatory cells and were made diabetic using streptozotocin injections. Retinal digestion using trypsin was performed and acellular capillaries enumerated. Capillary occlusion by GFP(+) cells was used to measure leukostasis. Overexpression of ACE2 prevented (prevention cohort: untreated diabetic, 11.3 ± 1.4; ACE2 diabetic, 6.4 ± 0.9 per mm(2)) and partially reversed (reversal cohort: untreated diabetic, 15.7 ± 1.9; ACE2 diabetic, 6.5 ± 1.2 per mm(2)) the diabetes-associated increase of acellular capillaries and the increase of infiltrating inflammatory cells into the retina (F4/80(+)) (prevention cohort: untreated diabetic, 24.2 ± 6.7; ACE2 diabetic, 2.5 ± 1.6 per mm(2); reversal cohort: untreated diabetic, 56.8 ± 5.2; ACE2 diabetic, 5.6 ± 2.3 per mm(2)). In both study cohorts, intracapillary bone marrow-derived cells, indicative of leukostasis, were only observed in diabetic animals receiving control AAV injections. These results indicate that diabetic retinopathy, and possibly other diabetic microvascular complications, can be prevented and reversed by locally restoring the balance between the classic and vasoprotective renin angiotensin system.


Assuntos
Retinopatia Diabética/enzimologia , Peptidil Dipeptidase A/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Dependovirus , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1 , Retinopatia Diabética/patologia , Terapia Genética/métodos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL
9.
Stem Cells ; 34(2): 405-17, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26502796

RESUMO

Ataxia telangiectasia mutated (ATM) acts as a defense against a variety of bone marrow (BM) stressors. We hypothesized that ATM loss in BM-hematopoietic stem cells (HSCs) would be detrimental to both HSC function and microvascular repair while sustained ATM would be beneficial in disease models of diabetes. Chronic diabetes represents a condition associated with HSC depletion and inadequate vascular repair. Gender mismatched chimeras of ATM(-/-) on wild type background were generated and a cohort were made diabetic using streptozotocin (STZ). HSCs from the STZ-ATM(-/-) chimeras showed (a) reduced self-renewal; (b) decreased long-term repopulation; (c) depletion from the primitive endosteal niche; (d) myeloid bias; and (e) accelerated diabetic retinopathy (DR). To further test the significance of ATM in hematopoiesis and diabetes, we performed microarrays on circulating angiogenic cells, CD34(+) cells, obtained from a unique cohort of human subjects with long-standing (>40 years duration) poorly controlled diabetes that were free of DR. Pathway analysis of microarrays in these individuals revealed DNA repair and cell-cycle regulation as the top networks with marked upregulation of ATM mRNA compared with CD34(+) cells from diabetics with DR. In conclusion, our study highlights using rodent models and human subjects, the critical role of ATM in microvascular repair in DR.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/biossíntese , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Regulação para Cima , Adulto , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Diabetes Mellitus Experimental/genética , Retinopatia Diabética/genética , Retinopatia Diabética/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade
10.
Chemistry ; 23(47): 11338-11345, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28621483

RESUMO

Chondroitin sulfate (CS) is a member of the glycosaminoglycan (GAG) family, a class of polysaccharides implicated in relevant biological functions. The structural complexity of these carbohydrates demands the development of simple glycomimetics as useful tools to study the biological processes in which GAGs are involved. In this work we described the synthesis of the disaccharide unit of the CS-E (GlcA-GalNAc(4,6-di-OSO3 )), in a multivalent presentation. Using a fluorescence polarization competition assay we have demonstrated that a hexavalent dendrimer of this disaccharide interact with midkine, in the low micromolar range. This result highlights the potency of these disaccharide-displaying multivalent systems as interesting mimetics of longer and synthetically more complex GAG oligosaccharides.


Assuntos
Sulfatos de Condroitina/química , Citocinas/metabolismo , Dendrímeros/química , Reação de Cicloadição , Citocinas/química , Dendrímeros/síntese química , Dendrímeros/metabolismo , Polarização de Fluorescência , Glicosaminoglicanos/química , Humanos , Concentração Inibidora 50 , Midkina , Ligação Proteica
11.
Int J Mol Sci ; 18(6)2017 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-28629128

RESUMO

FGF-1 is a potent mitogen that, by interacting simultaneously with Heparan Sulfate Glycosaminoglycan HSGAG and the extracellular domains of its membrane receptor (FGFR), generates an intracellular signal that finally leads to cell division. The overall structure of the ternary complex Heparin:FGF-1:FGFR has been finally elucidated after some controversy and the interactions within the ternary complex have been deeply described. However, since the structure of the ternary complex was described, not much attention has been given to the molecular basis of the interaction between FGF-1 and the HSGAG. It is known that within the complex, the carbohydrate maintains the same helical structure of free heparin that leads to sulfate groups directed towards opposite directions along the molecular axis. The precise role of single individual interactions remains unclear, as sliding and/or rotating of the saccharide along the binding pocket are possibilities difficult to discard. The HSGAG binding pocket can be subdivided into two regions, the main one can accommodate a trisaccharide, while the other binds a disaccharide. We have studied and analyzed the interaction between FGF-1 and a library of trisaccharides by STD-NMR and selective longitudinal relaxation rates. The library of trisaccharides corresponds to the heparin backbone and it has been designed to interact with the main subsite of the protein.


Assuntos
Fator 1 de Crescimento de Fibroblastos/química , Heparina/química , Imageamento por Ressonância Magnética/métodos , Trissacarídeos/química , Sítios de Ligação , Fenômenos Biofísicos , Cristalografia por Raios X , Dissacarídeos , Heparitina Sulfato/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína
13.
Am J Physiol Endocrinol Metab ; 308(8): E688-98, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25714673

RESUMO

Neuroinflammation and neurodegeneration have been observed in the brain in type 1 diabetes (T1D). However, little is known about the mediators of these effects. In T1D mice with 12- and 35-wk duration of diabetes we examined two mechanisms of neurodegeneration, loss of the neuroprotective factors insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) and changes in indoleamine 2,3-dioxygenase (IDO) expression in the brain, and compared the response to age-matched controls. Furthermore, levels of matrix metalloproteinase-2 (MMP-2), nucleoside triphosphate diphosphohydrolase-1 (CD39), and ionized calcium-binding adaptor molecule 1 (Iba-1) were utilized to assess inflammatory changes in astrocytes, microglia, and blood vessels. In the diabetic hypothalamus (HYPO), we observed 20% reduction in neuronal soma diameter (P<0.05) and reduced neuronal expression of IGFBP-3 (-32%, P<0.05) and IGF-I (-15%, P<0.05) compared with controls at 35 wk. In diabetic HYPO, MMP-2 expression was increased in astrocytes (46%, P<0.01), and IDO⁺ cell density rose by (62%, P<0.05). CD39 expression dropped by 30% (P<0.05) in microglia and blood vessels. With 10 wk of systemic treatment using minocycline, an anti-inflammatory agent that crosses the blood-brain barrier, MMP-2, IDO, and CD39 levels normalized (P<0.05). Our results suggest that increased IDO and early loss of CD39⁺ protective cells lead to activation of inflammation in sympathetic centers of the CNS. As a downstream effect, the loss of the neuronal survival factors IGFBP-3 and IGF-I and the neurotoxic products of the kynurenine pathway contribute to the loss of neuronal density observed in the HYPO in T1D.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/metabolismo , Regulação para Baixo , Encefalite/complicações , Hipotálamo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sistema Nervoso Simpático/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Astrócitos/metabolismo , Astrócitos/patologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/fisiopatologia , Neuropatias Diabéticas/imunologia , Neuropatias Diabéticas/patologia , Neuropatias Diabéticas/prevenção & controle , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Encefalite/imunologia , Encefalite/metabolismo , Encefalite/prevenção & controle , Hipotálamo/efeitos dos fármacos , Hipotálamo/imunologia , Hipotálamo/patologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/imunologia , Microglia/metabolismo , Microglia/patologia , Minociclina/uso terapêutico , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurônios/efeitos dos fármacos , Neurônios/imunologia , Neurônios/metabolismo , Neurônios/patologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/imunologia , Sistema Nervoso Simpático/patologia , Regulação para Cima/efeitos dos fármacos
14.
Adv Exp Med Biol ; 870: 49-122, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26387100

RESUMO

Thanks to recent improvements in NMR instrumentation, pulse sequence design, and sample preparation, a panoply of new NMR tools has become available for atomic resolution characterization of intrinsically disordered proteins (IDPs) that are optimized for the particular chemical and spectroscopic properties of these molecules. A wide range of NMR observables can now be measured on increasingly complex IDPs that report on their structural and dynamic properties in isolation, as part of a larger complex, or even inside an entire living cell. Herein we present basic NMR concepts, as well as optimised tools available for the study of IDPs in solution. In particular, the following sections are discussed hereafter: a short introduction to NMR spectroscopy and instrumentation (Sect. 3.1), the effect of order and disorder on NMR observables (Sect. 3.2), particular challenges and bottlenecks for NMR studies of IDPs (Sect. 3.3), 2D HN and CON NMR experiments: the fingerprint of an IDP (Sect. 3.4), tools for overcoming major bottlenecks of IDP NMR studies (Sect. 3.5), 13C detected experiments (Sect. 3.6), from 2D to 3D: from simple snapshots to site-resolved characterization of IDPs (Sect. 3.7), sequential NMR assignment: 3D experiments (Sect. 3.8), high-dimensional NMR experiments (nD, with n>3) (Sect. 3.9) and conclusions and perspectives (Sect. 3.10).


Assuntos
Proteínas Intrinsicamente Desordenadas/química , Ressonância Magnética Nuclear Biomolecular/métodos , Conformação Proteica
16.
J Biomol NMR ; 60(1): 1-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25056271

RESUMO

Three experiments, BEST-TROSY HNCA+, HNCO+ and HNCACB+ are presented for sequential backbone resonance assignment of (13)C, (15)N labelled proteins. The novelty of these experiments with respect to conventional pulse sequences is the detection of additional orthogonal coherence transfer pathways that results in enhanced sensitivity for sequential correlations without significantly compromising the intensity of intra-residue correlation peaks. In addition, a 2-step phase cycle separates peaks originating from the orthogonal coherence transfer pathways in 2 sub-spectra, thus providing similar information as obtained from performing a pair of sequential and intra-residue correlation experiments.


Assuntos
Isótopos de Carbono/química , Isótopos de Nitrogênio/química , Ressonância Magnética Nuclear Biomolecular/métodos , Proteínas/química
17.
Am J Pathol ; 183(5): 1608-20, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24160325

RESUMO

By using pseudorabies virus expressing green fluorescence protein, we found that efferent bone marrow-neural connections trace to sympathetic centers of the central nervous system in normal mice. However, this was markedly reduced in type 1 diabetes, suggesting a significant loss of bone marrow innervation. This loss of innervation was associated with a change in hematopoiesis toward generation of more monocytes and an altered diurnal release of monocytes in rodents and patients with type 1 diabetes. In the hypothalamus and granular insular cortex of mice with type 1 diabetes, bone marrow-derived microglia/macrophages were activated and found at a greater density than in controls. Infiltration of CD45(+)/CCR2(+)/GR-1(+)/Iba-1(+) bone marrow-derived monocytes into the hypothalamus could be mitigated by treatment with minocycline, an anti-inflammatory agent capable of crossing the blood-brain barrier. Our studies suggest that targeting central inflammation may facilitate management of microvascular complications.


Assuntos
Medula Óssea/inervação , Medula Óssea/patologia , Sistema Nervoso Central/patologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Inflamação/patologia , Animais , Medula Óssea/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Proteínas de Fluorescência Verde/metabolismo , Hematopoese/efeitos dos fármacos , Herpesvirus Suídeo 1/efeitos dos fármacos , Herpesvirus Suídeo 1/fisiologia , Humanos , Inflamação/complicações , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Minociclina/farmacologia , Modelos Biológicos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Neurotransmissores/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/metabolismo , Sistema Nervoso Simpático/patologia
18.
Int Emerg Nurs ; 74: 101450, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688204

RESUMO

INTRODUCTION: Stress, described as an adaptation of the body to an event, is a considerable problem among health workers, especially for those who work in emergency situations, as they very often have to face complex situations. It has been proven that stress affects the performance of health professionals, which is why it is interesting to measure it in these situations, to be able to know what methods to implement to reduce it in future events. Despite having previous measurements in healthcare personnel during clinical simulations, this study is relevant because stress has never before been measured in EMS professionals when performing their work. OBJECTIVE: To determine the acute stress experienced by professionals in an Emergency Medical Service (EMS) when handling five types of clinical emergencies. As secondary objectives, to determine if there were differences in the increases in stress in relation to sex, age, profession, team, and above all, type of emergency handled. METHOD: The following were measured for the analysis: physiological (mean heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure), and biochemical (salivary alpha amylase (sAA) activity) markers, before (Basal) and after (Post-Stress) the interventions of 27 professionals from an EMS. RESULTS: In general, the results obtained showed significant differences between the baseline measurement of physiological and biochemical markers versus the post-exposure measurement. Some of the differences in stress levels in relation to sex and professional role are striking. CONCLUSION: The determination of acute stress experienced by professionals from an EMS in a real emergency showed significant increases in the sAA enzymatic marker of acute stress. These results are the first data published in this regard, and could be used as a reference to follow in clinical simulation in the training of students and the training of nursing professionals. IMPLICATIONS FOR CLINICAL PRACTICE: Evidence based studies are needed to improve the education and training of emergency and intensive care professionals. The results from are a great step in the analysis of the real stress that professionals are subjected to when they handle different emergencies.


Assuntos
Serviços Médicos de Emergência , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Frequência Cardíaca/fisiologia , Estresse Psicológico , Pressão Sanguínea , Biomarcadores , Pessoal de Saúde/psicologia
19.
J Exp Med ; 204(3): 605-18, 2007 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-17339405

RESUMO

Stromal cell-derived factor 1 (SDF-1) plays a major role in the migration, recruitment, and retention of endothelial progenitor cells to sites of ischemic injury and contributes to neovascularization. We provide direct evidence demonstrating an important role for heme oxygenase 1 (HO-1) in mediating the proangiogenic effects of SDF-1. Nanomolar concentrations of SDF-1 induced HO-1 in endothelial cells through a protein kinase C zeta-dependent and vascular endothelial growth factor-independent mechanism. SDF-1-induced endothelial tube formation and migration was impaired in HO-1-deficient cells. Aortic rings from HO-1(-/-) mice were unable to form capillary sprouts in response to SDF-1, a defect reversed by CO, a byproduct of the HO-1 reaction. Phosphorylation of vasodilator-stimulated phosphoprotein was impaired in HO-1(-/-) cells, an event that was restored by CO. The functional significance of HO-1 in the proangiogenic effects of SDF-1 was confirmed in Matrigel plug, wound healing, and retinal ischemia models in vivo. The absence of HO-1 was associated with impaired wound healing. Intravitreal adoptive transfer of HO-1-deficient endothelial precursors showed defective homing and reendothelialization of the retinal vasculature compared with HO-1 wild-type cells following ischemia. These findings demonstrate a mechanistic role for HO-1 in SDF-1-mediated angiogenesis and provide new avenues for therapeutic approaches in vascular repair.


Assuntos
Quimiocinas CXC/fisiologia , Heme Oxigenase-1/fisiologia , Neovascularização Fisiológica , Animais , Células Cultivadas , Quimiocina CXCL12 , Células Endoteliais/enzimologia , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiologia , Heme Oxigenase-1/deficiência , Heme Oxigenase-1/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Estromais/enzimologia , Cicatrização/genética , Cicatrização/fisiologia
20.
Sci Rep ; 12(1): 15489, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109609

RESUMO

Lemon balm is herbal tea used for soothing stomach cramps, indigestion, and nausea. Rosmarinic acid (RA) is one of its chemical constituents known for its therapeutic potentials against cancer, inflammatory and neuronal diseases such as the treatment of neurofibromatosis or prevention from Alzheimer's diseases (AD). Despite efforts, recovery and purification of RA in high yields has not been entirely successful. Here, we report its aqueous extraction with optimal conditions and decipher the structure by nuclear magnetic resonance (NMR) spectroscopy. Using various physical-chemical and biological assays, we highlight its anti-aggregation inhibition potentials against the formation of Tau filaments, one of the hallmarks of AD. We then examine its anti-cancer potentials through reduction of the mitochondrial reductase activity in tumor cells and investigate its electrochemical properties by cyclic voltammetry. Our data demonstrates that RA is a prominent biologically active natural product with therapeutic potentials for drug discovery in AD, cancer therapy and inflammatory diseases.


Assuntos
Doença de Alzheimer , Produtos Biológicos , Chás de Ervas , Doença de Alzheimer/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Cinamatos , Depsídeos/química , Humanos , Oxirredutases , Ácido Rosmarínico
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