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1.
Nat Immunol ; 23(2): 217-228, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35102344

RESUMO

During inflammation, Ly6Chi monocytes are rapidly mobilized from the bone marrow (BM) and are recruited into inflamed tissues, where they undergo monocyte-to-phagocyte transition (MTPT). The in vivo developmental trajectories of the MTPT and the contribution of individual cytokines to this process remain unclear. Here, we used a murine model of neuroinflammation to investigate how granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon-γ (IFNγ), two type 1 cytokines, controlled MTPT. Using genetic fate mapping, gene targeting and high-dimensional single-cell multiomics analyses, we found that IFNγ was essential for the gradual acquisition of a mature inflammatory phagocyte phenotype in Ly6Chi monocytes, while GM-CSF was required to license interleukin-1ß (IL-1ß) production, phagocytosis and oxidative burst. These results suggest that the proinflammatory cytokine environment guided MTPT trajectories in the inflamed central nervous system (CNS) and indicated that GM-CSF was the most prominent target for the disarming of monocyte progenies during neuroinflammation.


Assuntos
Diferenciação Celular/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interferon gama/metabolismo , Monócitos/metabolismo , Doenças Neuroinflamatórias/metabolismo , Fagócitos/metabolismo , Animais , Citocinas/metabolismo , Feminino , Macrófagos/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/fisiologia , Doenças Neuroinflamatórias/fisiopatologia , Fagócitos/fisiologia
3.
J Cogn Neurosci ; : 1-15, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38437192

RESUMO

We studied the attributes of cytochrome c oxidase (CytOx)-rich blobs and ocular dominance columns (OD) in human V1 associated with monocular retinal lesions. Interblob distance, blob cross-sectional area, OD width, and OD arrangement pattern were analyzed in CytOx-reacted tangential sections of flat-mounted V1 preparations. Monocular deprivation induces differential expression of CytOx in the corresponding ODs in V1. We were thereby able to identify the V1 regions associated with the lesioned area in the retina, assign which OD was associated with each eye, and assign the corresponding blob in Layer III as deprived or nondeprived of visual input. We found that nondeprived blobs are more conspicuously stained than blobs outside the lesioned area. Notably, we found a selective expansion of blobs associated with the nonlesioned eye, whereas blobs associated with the deprived eye showed no significant change in size. Blob size in the latter condition was similar to the one observed in normal participants. These effects were present throughout the representation of the lesion in V1, suggesting that the underlying plasticity mechanisms do not depend on eccentricity. Retinal lesion caused no change in interblob distance, which was comparable to the normal brain (i.e., participants with no retinal lesion). This indicates that blob center is a stable hallmark of cortical organization. Finally, the width of ODs associated with the nonlesioned eye tended to be larger compared with ODs of the lesioned eye. However, this effect did not reach statistical significance. The stability of ODs thereby contrasts with blob plasticity, suggesting that the retinal lesion-triggered imbalance in the thalamocortical projection to Layer IVc has a limited impact on OD CytOx reactivity. On the other hand, we argue that ocular imbalance supports intracortical lateral competition that increases CytOx reactivity in the periblob region associated with the nonlesioned eye, accounting for the blob expansion we observe.

4.
Chem Res Toxicol ; 37(6): 827-849, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758610

RESUMO

The attrition rate of drugs in clinical trials is generally quite high, with estimates suggesting that approximately 90% of drugs fail to make it through the process. The identification of unexpected toxicity issues during preclinical stages is a significant factor contributing to this high rate of failure. These issues can have a major impact on the success of a drug and must be carefully considered throughout the development process. These late-stage rejections or withdrawals of drug candidates significantly increase the costs associated with drug development, particularly when toxicity is detected during clinical trials or after market release. Understanding drug-biological target interactions is essential for evaluating compound toxicity and safety, as well as predicting therapeutic effects and potential off-target effects that could lead to toxicity. This will enable scientists to predict and assess the safety profiles of drug candidates more accurately. Evaluation of toxicity and safety is a critical aspect of drug development, and biomolecules, particularly proteins, play vital roles in complex biological networks and often serve as targets for various chemicals. Therefore, a better understanding of these interactions is crucial for the advancement of drug development. The development of computational methods for evaluating protein-ligand interactions and predicting toxicity is emerging as a promising approach that adheres to the 3Rs principles (replace, reduce, and refine) and has garnered significant attention in recent years. In this review, we present a thorough examination of the latest breakthroughs in drug toxicity prediction, highlighting the significance of drug-target binding affinity in anticipating and mitigating possible adverse effects. In doing so, we aim to contribute to the development of more effective and secure drugs.


Assuntos
Desenvolvimento de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Animais
5.
Br J Nutr ; 131(8): 1447-1451, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38012852

RESUMO

The link between school feeding programmes (SFP) and the promotion of healthy eating and health is being explored in studies performed in different countries. The coronavirus disease-19 pandemic has revealed flaws and weaknesses in contemporary food systems, with many school-age children experiencing food insecurity and hunger. There is intense debate among policymakers regarding whether government SFP should be universal or targeted. Countries such as Brazil and India, which have two of the most comprehensive universal free-of-charge programmes, have shown the benefits of SFP, including improved nutritional status, support for more sustainable food systems, attendance and academic performance. Evidence shows and supports actions advocating that it is time to offer healthy and free school meals for all students.


Assuntos
Serviços de Alimentação , Criança , Humanos , Refeições , Instituições Acadêmicas , Estado Nutricional , Estudantes
6.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33653955

RESUMO

Pericytes regulate the development of organ-specific characteristics of the brain vasculature such as the blood-brain barrier (BBB) and astrocytic end-feet. Whether pericytes are involved in the control of leukocyte trafficking in the adult central nervous system (CNS), a process tightly regulated by CNS vasculature, remains elusive. Using adult pericyte-deficient mice (Pdgfbret/ret ), we show that pericytes limit leukocyte infiltration into the CNS during homeostasis and autoimmune neuroinflammation. The permissiveness of the vasculature toward leukocyte trafficking in Pdgfbret/ret mice inversely correlates with vessel pericyte coverage. Upon induction of experimental autoimmune encephalomyelitis (EAE), pericyte-deficient mice die of severe atypical EAE, which can be reversed with fingolimod, indicating that the mortality is due to the massive influx of immune cells into the brain. Additionally, administration of anti-VCAM-1 and anti-ICAM-1 antibodies reduces leukocyte infiltration and diminishes the severity of atypical EAE symptoms of Pdgfbret/ret mice, indicating that the proinflammatory endothelium due to absence of pericytes facilitates exaggerated neuroinflammation. Furthermore, we show that the presence of myelin peptide-specific peripheral T cells in Pdgfbret/ret ;2D2tg mice leads to the development of spontaneous neurological symptoms paralleled by the massive influx of leukocytes into the brain. These findings indicate that intrinsic changes within brain vasculature can promote the development of a neuroinflammatory disorder.


Assuntos
Barreira Hematoencefálica/imunologia , Encefalomielite Autoimune Experimental/imunologia , Homeostase/imunologia , Leucócitos/imunologia , Pericitos/imunologia , Animais , Barreira Hematoencefálica/patologia , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/patologia , Homeostase/genética , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/imunologia , Leucócitos/patologia , Camundongos , Camundongos Transgênicos , Pericitos/patologia , Proteínas Proto-Oncogênicas c-sis/deficiência , Proteínas Proto-Oncogênicas c-sis/imunologia , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/imunologia
7.
Int Microbiol ; 26(4): 1123-1130, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37140807

RESUMO

Microalgae are photosynthetic organisms that can produce biomolecules with industrial interest, including exopolysaccharides (EPS). Due to their structural and compositional diversity, microalgae EPS present interesting properties that can be considered in cosmetic and/or therapeutic areas. Seven microalgae strains from three different lineages, namely Dinophyceae (phylum Miozoa), Haptophyta, and Chlorophyta, were investigated as EPS producers. All strains were found to be EPS producers, though the highest EPS yield was obtained for Tisochrysis lutea, followed by Heterocapsa sp. (126.8 and 75.8 mg L-1, respectively). Upon assessment of the polymers' chemical composition, significant contents of unusual sugars, including fucose, rhamnose, and ribose, were found. Heterocapsa sp. EPS stood out due to its high content of fucose (40.9 mol%), a sugar known to confer biological properties to polysaccharides. The presence of sulfate groups (10.6-33.5 wt%) was also noticed in the EPS produced by all microalgae strains, thus contributing to the possibility that these EPS might have biological activities worth exploring.


Assuntos
Microalgas , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Fucose , Bioprospecção
8.
Public Health Nutr ; 26(12): 3331-3342, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905595

RESUMO

OBJECTIVE: To analyse the purchase of food for school feeding, according to the extent and purpose of industrial processing and variety, exploring the feasibility of achieving the requirements and recommendations of the Brazilian School Feeding Programme, and the variety of unprocessed or minimally processed foods according to the purchase of ultra-processed foods. DESIGN: Secondary data from 2016 from the Accountability Management System of the National Fund for Educational Development, concerning the food items purchased, were used to explore the feasibility of the requirements and recommendations. The foods were grouped according to the NOVA classification system. Variety was assessed by counting different types of unprocessed or minimally processed foods. SETTING: Brazil. PARTICIPANTS: 3698 Brazilian municipalities. RESULTS: Energy share from unprocessed or minimally processed foods was 44·1 % while that of ultra-processed foods was 29·9 %. The average of unprocessed or minimally processed food types purchased annually was 33·8 items. Of the municipalities, 35·8 % were within the limit established for the expenditure of funds for the purchase of processed and ultra-processed foods, while 8·7 % followed the recommendation for variety. The proportion of ultra-processed foods did not influence the variety of food items purchased. CONCLUSIONS: The results showed the feasibility of achieving the requirements and recommendations and underscored the importance of continued efforts to promote the inclusion of unprocessed or minimally processed foods in the school feeding programme while addressing the challenges associated with expenditure limits of processed and ultra-processed foods and enhancing variety, which is strategic to promote adequate and healthy meals.


Assuntos
Manipulação de Alimentos , Refeições , Humanos , Brasil , Estudos de Viabilidade , Instituições Acadêmicas , Fast Foods , Dieta , Ingestão de Energia
9.
Eur J Immunol ; 51(6): 1423-1435, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33547634

RESUMO

Antibodies play an important role in host defense against microorganisms. Besides direct microbicidal activities, antibodies can also provide indirect protection via crosstalk to constituents of the adaptive immune system. Similar to many human chronic viral infections, persistence of Lymphocytic choriomeningitis virus (LCMV) is associated with compromised T- and B-cell responses. The administration of virus-specific non-neutralizing antibodies (nnAbs) prior to LCMV infection protects against the establishment of chronic infection. Here, we show that LCMV-specific nnAbs bind preferentially Ly6Chi inflammatory monocytes (IMs), promote their infection in an Fc-receptor independent way, and support acquisition of APC properties. By constituting additional T-cell priming opportunities, IMs promote early activation of virus-specific CD8 T cells, eventually tipping the balance between T-cell exhaustion and effector cell differentiation, preventing establishment of viral persistence without causing lethal immunopathology. These results document a beneficial role of IMs in avoiding T-cell exhaustion and an Fc-receptor independent protective mechanism provided by LCMV-specific nnAbs against the establishment of chronic infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vírus da Coriomeningite Linfocítica/fisiologia , Monócitos/imunologia , Animais , Anticorpos Antivirais , Antígenos Ly/metabolismo , Antígenos Virais/imunologia , Diferenciação Celular , Células Cultivadas , Senescência Celular , Doença Crônica , Resistência à Doença , Humanos , Inflamação , Ativação Linfocitária , Coriomeningite Linfocítica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/virologia , Receptores de IgG/genética
10.
J Phycol ; 58(3): 465-486, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35234279

RESUMO

The taxonomy of the extant dinoflagellate genus Gonyaulax is challenging since its thecate morphology is rather conservative. In contrast, cysts of Gonyaulax are varied in morphology and have been related with the fossil-based genera Spiniferites and Impagidinium. To better understand the systematics of Gonyaulax species, we performed germination experiments on cysts that can be identified as S. ristingensis, an unidentified Spiniferites with petaloid processes here described as Spiniferites pseudodelicatus sp. nov. and Impagidinium variaseptum from Chinese and Portuguese waters. Despite marked differences in cyst morphology, motile cells of S. pseudodelicatus and I. variaseptum are indistinguishable from Gonyaulax baltica. Motile cells hatched from S. ristingensis are morphologically similar to G. baltica as well but differ in the presence of one pronounced antapical spine. Three new species, Gonyaulax amoyensis (cyst equivalent S. pseudodelicatus), Gonyaulax bohaiensis (cyst equivalent I. variaseptum), and Gonyaulax portimonensis (cyst equivalent S. ristingensis), were erected. In addition, a new ribotype (B) of G. baltica was reported from South Korea and a bloom of G. baltica ribotype B is reported from New Zealand. Molecular phylogeny based on LSU and SSU rRNA gene sequences revealed that Gonyaulax species with minute or short antapical spines formed a well-resolved clade, whereas species with two pronounced antapical spines or lack of antapical spines formed the sister clade. Six strains of four above species were examined for yessotoxin production by liquid chromatography coupled with tandem mass spectrometry, and very low concentrations of yessotoxin were detected for one G. bohaiensis strain.


Assuntos
Dinoflagellida , Cromatografia Líquida , Dinoflagellida/genética , Filogenia , República da Coreia , Espectrometria de Massas em Tandem
11.
Eur J Neurol ; 28(12): 4258-4260, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34773322

RESUMO

Cerebral venous thrombosis (CVT) can rarely present with acute ipsilateral cochlear and/or vestibular loss, to date always in the absence of a clear local otogenic process evidenced by magnetic resonance imaging (MRI). This association has been putatively attributed to inner ear anoxia due to blockage of inner ear venous drainage. We present a nonreported case of thrombosis of the left transverse and sigmoid sinuses presenting with acute unilateral vestibulopathy in which MRI disclosed concurrent ipsilateral labyrinthine haemorrhage. A 69-year-old female presented with acute vertigo without hearing loss or other accompanying neurological symptoms. Bedside examination revealed spontaneous right-beating nystagmus and an impaired left head impulse response, with an otherwise normal neurological examination. Audiometry and head and ear computed tomography were unremarkable, whereas MRI showed a nonenhancing hyperintensity of the left inner ear consistent with labyrinthine haemorrhage, and additional venography disclosed thrombosis of the left transverse and sigmoid sinuses. Oral anticoagulation was started, and the patient experienced gradual improvement of symptoms. The current case provides support for the existence of inner ear anoxia in CVT cases presenting with acute ipsilateral vestibular loss, which can ultimately be complicated by secondary bleeding, as seen in our patient. Importantly, presentation in our case closely mimicked that of peripheral vestibular neuritis, and only MRI venography enabled us to make a prompt diagnosis. This raises an important question as to when a diagnosis of vestibular neuritis can be made securely in the absence of MRI assessment with or without venography to completely discard labyrinthine haemorrhage with or without CVT.


Assuntos
Orelha Interna , Trombose Intracraniana , Trombose Venosa , Idoso , Feminino , Hemorragia , Humanos , Trombose Intracraniana/complicações , Trombose Intracraniana/diagnóstico por imagem , Imageamento por Ressonância Magnética , Trombose Venosa/complicações , Trombose Venosa/diagnóstico por imagem
12.
Neurobiol Dis ; 124: 189-201, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30468865

RESUMO

Multiple sclerosis is an inflammatory disease of the central nervous system (CNS) in which multiple sites of blood-brain barrier (BBB) disruption, focal inflammation, demyelination and tissue destruction are the hallmarks. Here we show that sphingosine-1-phosphate receptor 2 (S1PR2) has a negative role in myelin repair as well as an important role in demyelination by modulating BBB permeability. In lysolecithin-induced demyelination of adult mouse spinal cord, S1PR2 inactivation by either the pharmacological inhibitor JTE-013 or S1PR2 gene knockout led to enhanced myelin repair as determined by higher numbers of differentiated oligodendrocytes and increased numbers of remyelinated axons at the lesion sites. S1PR2 inactivation in lysolecithin-induced demyelination of the optic chiasm, enhanced oligodendrogenesis and improved the behavioral outcome in an optokinetic reflex test. In order to see the effect of S1PR2 inactivation on demyelination, experimental autoimmune encephalitis (EAE) was induced by MOG-peptide. S1PR2 inhibition or knockout decreased the extent of demyelinated areas as well as the clinical disability in this EAE model. Both toxin induced and EAE models showed decreased BBB leakage and reduced numbers of Iba1+ macrophages following S1PR2 inactivation. Our results suggest that S1PR2 activity impairs remyelination and also enhances BBB leakage and demyelination. The former effect could be mediated by Nogo-A, as antagonism of this factor enhances remyelination and S1PR2 can act as a Nogo-A receptor.


Assuntos
Esclerose Múltipla/fisiopatologia , Remielinização , Receptores de Esfingosina-1-Fosfato/fisiologia , Animais , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/fisiologia , Esclerose Múltipla/patologia , Bainha de Mielina/ultraestrutura , Receptores de Esfingosina-1-Fosfato/genética , Medula Espinal/patologia , Medula Espinal/fisiopatologia
13.
Limnol Oceanogr ; 64(6): 2709-2724, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32655189

RESUMO

The globally distributed heterotrophic dinoflagellate Noctiluca scintillans (Macartney) Kofoid & Swezy is well known for its dense blooms and prominent displays of bioluminescence. Intriguingly, along the west coast of the USA its blooms are not bioluminescent. We investigated the basis for the regional loss of bioluminescence using molecular, cellular and biochemical analyses of isolates from different geographic regions. Prominent differences of the non-bioluminescent strains were: (1) the fused luciferase and luciferin binding protein gene (lcf/lbp) was present but its transcripts were undetectable; (2) lcf/lbp contained multiple potentially deleterious mutations; (3) the substrate luciferin was absent, based on the lack of luciferin blue autofluorescence and the absence of luciferin derived metabolites; (4) although the cells possessed scintillons, the vesicles that contain the luminescent chemistry, electron microscopy revealed additional scintillon-like vesicles with an atypical internal structure; (5) cells isolated from the California coast were 43% smaller in size than bioluminescent cells from the Gulf of Mexico. Phylogenetic analyses based on the large subunit of rDNA did not show divergence of the non-bioluminescent population in relation to other bioluminescent N. scintillans from the Pacific Ocean and Arabian Sea. Our study demonstrates that gene silencing and the lack of the luciferin substrate have resulted in the loss of a significant dinoflagellate functional trait over large spatial scales in the ocean. As the bioluminescence system of dinoflagellates is well characterized, non-bioluminescent N. scintillans is an ideal model to explore the evolutionary and ecological mechanisms that lead to intraspecific functional divergence in natural dinoflagellate populations.

14.
J Neuroophthalmol ; 38(1): 32-35, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28767521

RESUMO

An immune attack by anti-glutamic acid decarboxylase (GAD) antibodies is believed to cause a deficiency in gamma-aminobutyric acid-mediated neurotransmission in the cerebellum. This, in turn, leads to several eye movement disorders, including spontaneous downbeat (DBN) and periodic alternating nystagmus. We describe a 68-year-old diabetic woman with disabling paroxysmal positioning upbeat nystagmus (UBN) exclusively in the supine position, associated with asymptomatic spontaneous DBN, alternating skew deviation and hyperactive vestibulo-ocular reflex responses on head impulse testing, in whom high titers of anti-GAD antibodies were detected. After treatment with intravenous immunoglobulin, a complete resolution of positioning UBN and spontaneous DBN occurred, along with a decrease in anti-GAD antibody titers. Positioning UBN in this case may reflect a transient disinhibition of the central vestibular pathways carrying posterior semicircular canal signals, due to lack of normal inhibitory input from the cerebellar nodulus/uvula. Immunoglobulin restored cerebellar inhibitory output, possibly by improving gamma-aminobutyric acid neurotransmission.


Assuntos
Autoanticorpos/sangue , Glutamato Descarboxilase/imunologia , Nistagmo Patológico/imunologia , Vertigem/imunologia , Idoso , Baclofeno/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Feminino , Agonistas dos Receptores de GABA-B/uso terapêutico , Humanos , Nistagmo Patológico/tratamento farmacológico , Nistagmo Patológico/fisiopatologia , Transtornos da Motilidade Ocular , Decúbito Dorsal , Vertigem/tratamento farmacológico , Vertigem/fisiopatologia
15.
Ecotoxicology ; 27(6): 661-674, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29909542

RESUMO

Studies addressing the predicted effects of pesticides in combination with abiotic and biotic factors on aquatic biota in ditches associated with typical Mediterranean agroecosystems are scarce. The current study aimed to evaluate the predicted effects of pesticides along with environmental factors and biota interactions on macroinvertebrate, zooplankton and phytoplankton community compositions in ditches adjacent to Portuguese maize and tomato crop areas. Data was analysed with the variance partitioning procedure based on redundancy analysis (RDA). The total variance in biological community composition was divided into the variance explained by the multi-substance potentially affected fraction [(msPAF) arthropods and primary producers], environmental factors (water chemistry parameters), biotic interactions, shared variance, and unexplained variance. The total explained variance reached 39.4% and the largest proportion of this explained variance was attributed to msPAF (23.7%). When each group (phytoplankton, zooplankton and macroinvertebrates) was analysed separately, biota interactions and environmental factors explained the largest proportion of variance. Results of this study indicate that besides the presence of pesticide mixtures, environmental factors and biotic interactions also considerably influence field freshwater communities. Subsequently, to increase our understanding of the risk of pesticide mixtures on ecosystem communities in edge-of-field water bodies, variations in environmental and biological factors should also be considered.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Biota , Água Doce/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Biota/efeitos dos fármacos , Meio Ambiente , Monitoramento Ambiental , Invertebrados/efeitos dos fármacos , Solanum lycopersicum , Fitoplâncton/efeitos dos fármacos , Portugal , Zea mays , Zooplâncton/efeitos dos fármacos
16.
J Paediatr Child Health ; 58(9): 1697, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34652036
17.
Nutr Cancer ; 68(7): 1108-14, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27485861

RESUMO

The aim of this study is to describe and relate nutritional and inflammatory status and prognostic indexes with postoperative complications and clinical outcome of patients with gastrointestinal malignancies. Twenty-nine patients were evaluated; nutritional assessment was carried out by subjective and objective parameters; albumin, pre-albumin, C-reactive protein (CRP), and alpha-1-acid glycoprotein (AGP) were determined. To assess prognosis, the Glasgow scale, the Prognostic Inflammatory Nutritional Index (PINI), and CRP/albumin ratio were used; the clinical outcomes considered were hospital discharge and death. A high Subjective Global Assessment (SGA) score was associated with the occurrence of postoperative complications: 73% of the patients with postoperative complications had the highest SGA score, but only 6% of those without postoperative complications had the highest SGA score (P < 0.001). Greater occurrence of death was observed in patients with a high SGA score, low serum albumin, increased CRP, PINI > 1, and Glasgow score 2. There was a positive correlation between weight loss percentage with serum CRP levels (P = 0.002), CRP/albumin (P = 0.002), PINI (P = 0.002), and Glasgow score (P = 0.000). This study provides evidence that the assessment of the nutritional status and the use of prognostic indexes are good tools for predicting postoperative complications and clinical outcome in patients with gastrointestinal neoplasia.


Assuntos
Proteína C-Reativa/análise , Neoplasias Gastrointestinais/cirurgia , Desnutrição/complicações , Estado Nutricional , Complicações Pós-Operatórias/etiologia , Idoso , Biomarcadores/sangue , Brasil/epidemiologia , Feminino , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/imunologia , Humanos , Incidência , Mediadores da Inflamação/sangue , Estudos Longitudinais , Masculino , Desnutrição/sangue , Desnutrição/epidemiologia , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Avaliação Nutricional , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Valor Preditivo dos Testes , Prevalência , Prognóstico , Risco , Índice de Gravidade de Doença , Redução de Peso
18.
Rapid Commun Mass Spectrom ; 30(1): 61-8, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26661971

RESUMO

RATIONALE: The study of natural products by electrospray ionization tandem mass spectrometry (ESI-MS/MS) is an important strategy for the characterization of the major fragmentation reactions which can then help to determine the composition of complex mixtures. Application of ESI-MS/MS to a series of isopimarane diterpenes from Velloziaceae allowed the rationalization of their fragmentation mechanisms. METHODS: Velloziaceae diterpenes were isolated by silica gel column chromatography and investigated by ESI-MS/MS analysis. The fragmentation studies were performed on a quadrupole-time-of-flight instrument using N2 as the collision gas. To help rationalize the fragmentation pathways observed, the geometry and sites of reactivity of the diterpenes were obtained by theoretical calculations using the B3LYP/6-31 + G(d,p) model. Fragmentation mechanisms were proposed on the basis of the calculated protonation sites and product ions energies using density functional theory (DFT) methods. RESULTS: The presence of hydroxyl and carbonyl groups on the terpene core influences the protonation site observed. One compound showed a radical cation as the base peak. MS/MS spectra exhibit water elimination as the major fragmentation pathway (via two ways), either when protonation takes place on the oxygen atom, or through elimination after activation from hydrogen migration. After the elimination of water, the formation of an endocyclic double bond induces a sequential retro-Diels-Alder (RDA) reaction as the major fragmentation step. CONCLUSIONS: A thorough rational analysis of the fragmentation mechanisms of protonated Velloziaceae diterpenes was used to propose the dissociation mechanisms in ESI-MS/MS. The presence of esters in the side chain also influenced the intensity or occurrence of the observed protonated or cationized molecules in ESI-MS. These results will aid the identification of analogues in sample extracts in future metabolomics studies.


Assuntos
Abietanos/análise , Abietanos/química , Magnoliopsida/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Modelos Moleculares
19.
An Acad Bras Cienc ; 87(1): 331-493, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25714078

RESUMO

Hepatic encephalopathy (HE) encompasses a variety of neuropsychiatric symptoms, including anxiety and psychomotor dysfunction. Although HE is a frequent complication of liver cirrhosis, the neurobiological substrates responsible for its clinical manifestations are largely unclear. In the present study, male Wistar rats were bile duct-ligated (BDL), a procedure which induces liver cirrhosis, and on the 21st day after surgery tested in the elevated plus-maze (EPM) and in an open field for anxiety and locomotor activity measurements. Analysis of Fos protein immunoreactivity (Fos-ir) was used to better understand the neurobiological alterations present in BDL animals. Plasma levels of ammonia were quantified and histopathological analysis of the livers was performed. BDL rats showed a significant decrease in the percentage of entries and time spent in the open arms of the EPM, an anxiogenic effect. These animals also presented significant decreases in Fos-ir in the lateral septal nucleus and medial amygdalar nucleus. Their ammonia plasma levels were significantly higher when compared to the sham group and the diagnosis of cirrhosis was confirmed by histopathological analysis. These results indicate that the BDL model induces anxiogenic results, possibly related to changes in the activation of anxiety-mediating circuitries and to increases in ammonia plasma levels.


Assuntos
Ansiedade/fisiopatologia , Comportamento Animal/fisiologia , Química Encefálica/fisiologia , Cirrose Hepática/fisiopatologia , Atividade Motora/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Amônia/sangue , Animais , Ductos Biliares/cirurgia , Modelos Animais de Doenças , Imuno-Histoquímica , Ligadura , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Masculino , Ratos , Ratos Wistar
20.
Molecules ; 20(10): 19526-39, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26516829

RESUMO

In the North of Brazil (Pará and Amazonas states) the leaves of the plant Talinum triangulare (popular: cariru) replace spinach as food. From a phytochemical point of view, they are rich in compounds of the group of pheophytins. These substances, related to chlorophyll, have photophysical properties that give them potential application in photodynamic therapy. Human serum albumin (HSA) is one of the main endogenous vehicles for biodistribution of molecules by blood plasma. Association constants and thermodynamic parameters for the interaction of HSA with pheophytin from Talinum triangulare were studied by UV-Vis absorption, fluorescence techniques, and molecular modeling (docking). Fluorescence quenching of the HSA's internal fluorophore (tryptophan) at temperatures 296 K, 303 K, and 310 K, resulted in values for the association constants of the order of 104 L∙mol(-1), indicating a moderate interaction between the compound and the albumin. The negative values of ΔG° indicate a spontaneous process; ΔH° = 15.5 kJ∙mol(-1) indicates an endothermic process of association and ΔS° = 0.145 kJ∙mol(-1)∙K(-1) shows that the interaction between HSA and pheophytin occurs mainly by hydrophobic factors. The observed Trp fluorescence quenching is static: there is initial non-fluorescent association, in the ground state, HSA:Pheophytin. Possible solution obtained by a molecular docking study suggests that pheophytin is able to interact with HSA by means of hydrogen bonds with three lysine and one arginine residues, whereas the phytyl group is inserted in a hydrophobic pocket, close to Trp-214.


Assuntos
Cactaceae/química , Simulação de Acoplamento Molecular/métodos , Feofitinas/química , Albumina Sérica/química , Sítios de Ligação , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Fotoquimioterapia , Folhas de Planta/química , Espectrometria de Fluorescência/métodos
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