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1.
Glia ; 72(3): 546-567, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37987116

RESUMO

Although brain scars in adults have been extensively studied, there is less data available regarding scar formation during the neonatal period, and the involvement of peripheral immune cells in this process remains unexplored in neonates. Using a murine model of neonatal hypoxic-ischemic encephalopathy (HIE) and confocal microscopy, we characterized the scarring process and examined the recruitment of peripheral immune cells to cortical and hippocampal scars for up to 1 year post-insult. Regional differences in scar formation were observed, including the presence of reticular fibrotic networks in the cortex and perivascular fibrosis in the hippocampus. We identified chemokines with chronically elevated levels in both regions and demonstrated, through a parabiosis-based strategy, the recruitment of lymphocytes, neutrophils, and monocyte-derived macrophages to the scars several weeks after the neonatal insult. After 1 year, however, neutrophils and lymphocytes were absent from the scars. Our data indicate that peripheral immune cells are transient components of HIE-induced brain scars, opening up new possibilities for late therapeutic interventions.


Assuntos
Cicatriz , Hipóxia-Isquemia Encefálica , Adulto , Animais , Humanos , Camundongos , Cicatriz/patologia , Encéfalo/patologia , Macrófagos , Hipóxia-Isquemia Encefálica/patologia
2.
Plant Biotechnol J ; 22(5): 1224-1237, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38050338

RESUMO

Immune checkpoint blocking therapy targeting the PD-1/PD-L1 inhibitory signalling pathway has produced encouraging results in the treatment of a variety of cancers. Durvalumab (Imfinzi®) targeting PD-L1 is currently used for immunotherapy of several tumour malignancies. The Fc region of this IgG1 antibody has been engineered to reduce FcγR interactions with the aim of enhancing blockade of PD-1/PD-L1 interactions without the depletion of PD-L1-expressing immune cells. Here, we used Nicotiana benthamiana to produce four variants of Durvalumab (DL): wild-type IgG1 and its 'Fc-effector-silent' variant (LALAPG) carrying further modifications to increase antibody half-life (YTE); IgG4S228P and its variant (PVA) with Fc mutations to decrease binding to FcγRI. In addition, DL variants were produced with two distinct glycosylation profiles: afucosylated and decorated with α1,6-core fucose. Plant-derived DL variants were compared to the therapeutic antibody regarding their ability to (i) bind to PD-L1, (ii) block PD-1/PD-L1 inhibitory signalling and (iii) engage with the neonatal Fc receptor (FcRn) and various Fcγ receptors. It was found that plant-derived DL variants bind to recombinant PD-L1 and to PD-L1 expressed in gastrointestinal cancer cells and are able to effectively block its interaction with PD-1 on T cells, thereby enhancing their activation. Furthermore, we show a positive impact of Fc amino acid mutations and core fucosylation on DL's therapeutic potential. Compared to Imfinzi®, DL-IgG1 (LALAPG) and DL-IgG4 (PVA)S228P show lower affinity to CD32B inhibitory receptor which can be therapeutically favourable. Importantly, DL-IgG1 (LALAPG) also shows enhanced binding to FcRn, a key determinant of serum half-life of IgGs.


Assuntos
Anticorpos Monoclonais , Inibidores de Checkpoint Imunológico , Receptor de Morte Celular Programada 1 , Receptor de Morte Celular Programada 1/genética , Antígeno B7-H1/genética , Imunoglobulina G/genética
3.
Brain Behav Immun ; 118: 318-333, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460804

RESUMO

Zika virus (ZIKV), the causative agent of Zika fever, is a flavivirus transmitted by mosquitoes of the Aedes genus. Zika virus infection has become an international concern due to its association with severe neurological complications such as fetal microcephaly. Viral infection can induce the release of ATP in the extracellular environment, activating receptors sensitized by extracellular nucleotides, such as the P2X7 receptor. This receptor is the primary purinergic receptor involved in neuroinflammation, neurodegeneration, and immunity. In this work, we investigated the role of ATP-P2X7 receptor signaling in Zika-related brain abnormalities. Wild-type mice (WT) and P2X7 receptor-deficient (P2X7-/-) C57BL/6 newborn mice were subcutaneously inoculated with 5 × 106plaque-forming units of ZIKV or mock solution. P2X7 receptor expression increased in the brain of Zika virus-infected mice compared to the mock group. Comparative analyses of the hippocampi from WT and P2X7-/-mice revealed that the P2X7 receptor increased hippocampal damage in CA1/CA2 and CA3 regions. Doublecortin expression decreased significantly in the brains of ZIKV-infected mice. WT ZIKV-infected mice showed impaired motor performance compared to P2X7-/- infected mice. WT ZIKV-infected animals showed increased expression of glial markers GFAP (astrocytes) and IBA-1 (microglia) compared to P2X7-/- infected mice. Although the P2X7 receptor contributes to neuronal loss and neuroinflammation, WT mice were more efficient in controlling the viral load in the brain than P2X7 receptor-deficient mice. This result was associated with higher induction of TNF-α, IFN-ß, and increased interferon-stimulated gene expression in WT mice than P2X7-/-ZIKV-infected. Finally, we found that the P2X7 receptor contributes to inhibiting the neuroprotective signaling pathway AKT/mTOR while stimulating the caspase-3 activation, possibly two distinct pathways contributing to neurodegeneration. These findings suggest that ATP-P2X7 receptor signaling contributes to the antiviral response in the brain of ZIKV-infected mice while increasing neuronal loss, neuroinflammation, and related brain abnormalities.


Assuntos
Infecção por Zika virus , Zika virus , Gravidez , Feminino , Animais , Camundongos , Zika virus/genética , Doenças Neuroinflamatórias , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , Transdução de Sinais , Trifosfato de Adenosina
4.
Allergol Immunopathol (Madr) ; 52(3): 53-59, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721955

RESUMO

INTRODUCTION: Food allergies represent a growing public health concern, particularly among children. This study aims to examine egg allergy in pediatric patients and analyze the value of serum-specific immunoglobulin E (sIgE) levels as predictive biomarkers for oral food challenge (OFC) outcomes. METHODS: Retrospective study, involving pediatric patients with suspected IgE-mediated egg allergy, conducted at a tertiary hospital. RESULTS: Data from 176 pediatric patients were analyzed, revealing a higher male prevalence (59.1%). Most cases (40.3%) presented symptoms in the first year of life, predominantly mucocutaneous symptoms (46%). OFC results varied across various forms of egg presentation, with cooked egg being the most frequently tested food. Positive OFCs were observed in 14.6% (n = 36) of cases. The study identified specific egg protein biomarkers for positive OFC, with ovalbumin for raw egg (sIgE > 1.28 KUA/L; area under the curve [AUC] = 0.917; sensitivity [S] 100%; and specificity [Sp] 92%), ovomucoid for cooked egg (sIgE > 0.99 KUA/L; AUC = 0.788, 95%; S: 79%; and Sp: 74%), and ovomucoid for baked egg (sIgE> 4.63 KUA/L; AUC = 0.870; S: 80%; and Sp: 85%) showing predictive capacities. CONCLUSIONS: The findings underscore the importance of considering various forms of egg presentation in the diagnosis and management of egg allergy. The findings highlight the valuable discriminatory capacity and provided reliable biomarkers, such as ovalbumin for raw egg and ovomucoid for cooked and baked egg in risk assessment, aiding in predicting OFC outcomes and helping clinicians to make informed decisions in diagnosing and managing egg allergies, thus improving patient care and quality of life.


Assuntos
Alérgenos , Biomarcadores , Hipersensibilidade a Ovo , Imunoglobulina E , Humanos , Hipersensibilidade a Ovo/diagnóstico , Hipersensibilidade a Ovo/imunologia , Hipersensibilidade a Ovo/epidemiologia , Hipersensibilidade a Ovo/sangue , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Feminino , Estudos Retrospectivos , Pré-Escolar , Criança , Lactente , Portugal/epidemiologia , Alérgenos/imunologia , Biomarcadores/sangue , Adolescente , Prevalência , Ovos/efeitos adversos
5.
Oncology ; 101(5): 292-302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36657399

RESUMO

BACKGROUND: Malignant primary cardiac tumors are exceedingly rare, and despite surgical exeresis or chemotherapy, their prognosis remains poor. Cardiac invasion by metastatic tumors, while more common, also entails an unsatisfactory outcome. This study aimed to review patients diagnosed with malignant primary and secondary cardiac tumors in a tertiary center between 1995 and 2022. METHODS: Clinical data, echocardiographic, computed tomography, and magnetic resonance assessments of tumor location and morphology, histology, treatment, and survival were retrospectively analyzed. RESULTS: Sixty malignant cardiac tumors were diagnosed: 17 primary (A) and 43 metastatic (B) tumors. A: the most common types were angiosarcoma (41%), undifferentiated sarcoma (23%), and fibrosarcoma (18%). Patients with primary tumors were younger than patients with metastatic tumors (41 ± 13 years vs. 57 ± 18 years, p = 0.001), with no significant gender difference. The most frequent presentations were heart failure (59%) and arrhythmia (23%). The most prevalent tumor location was the right heart chambers (71%), mostly in the right atrium (35%). 47% were submitted to tumor resection, and 29% received chemotherapy. The mortality rate was 82% with a median survival of 6.0 (interquartile range: 1.0-11.8) months after diagnosis (minimum of 12 days and maximum of 19 years). One patient with fibrosarcoma underwent heart transplantation and was still alive and well after 19 years. B: regarding metastatic cardiac invasion, the most common primary tumor sites were lung carcinomas (38%), thymomas (17%), and lymphomas (14%). Presentation with pericardial effusion was common (33%). The mortality rate was 72%, with a median survival of 3.6 (1.0-13.4) months (minimum of 7 days, maximum of 5 years). CONCLUSION: Diagnosis of metastatic cardiac tumors was more common than that of malignant primary tumors, both with a dismal prognosis. When radical exeresis is not possible, heart transplantation can be an option with a favorable outcome in carefully selected patients with sarcomas.


Assuntos
Fibrossarcoma , Neoplasias Cardíacas , Hemangiossarcoma , Sarcoma , Humanos , Estudos Retrospectivos , Hemangiossarcoma/patologia , Hemangiossarcoma/cirurgia , Sarcoma/diagnóstico , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/diagnóstico
6.
Eur J Neurol ; 30(10): 2999-3007, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37402214

RESUMO

BACKGROUND: Cerebrovascular disease (CVD) is a major contributor to epilepsy; however, patients with epilepsy also have a significantly increased risk of stroke. The way in which epilepsy contributes to the increased risk of stroke is still uncertain and is ill-characterized in neuropathological studies. A neuropathological characterization of cerebral small vessel disease (cSVD) in patients with chronic epilepsy was performed. METHODS: Thirty-three patients with refractory epilepsy and hippocampal sclerosis (HS) submitted to epilepsy surgery from a reference center were selected between 2010 and 2020 and compared with 19 autopsy controls. Five randomly selected arterioles from each patient were analyzed using a previously validated scale for cSVD. The presence of CVD disease imaging markers in pre-surgical brain magnetic resonance imaging (MRI) was studied. RESULTS: There were no differences in age (43.8 vs. 41.6 years; p = 0.547) or gender distribution (female gender 60.6% vs. male gender 52.6%; p = 0.575) between groups. Most CVD findings in brain MRI were mild. Patients had a mean time between the epilepsy onset and surgery of 26 ± 14.7 years and were medicated with a median number of three antiseizure medication (ASMs) [IQR 2-3]. Patients had higher median scores in arteriolosclerosis (3 vs. 1; p < 0.0001), microhemorrhages (4 vs. 1; p < 0.0001) and total score value (12 vs. 8.9; p = 0.031) in comparison with controls. No correlation was found between age, number of years until surgery, number of ASMs or cumulative defined daily dosage of ASM. CONCLUSION: The present study provides evidence supporting the increased burden of cSVD in the neuropathological samples of patients with chronic epilepsy.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Transtornos Cerebrovasculares , Epilepsia do Lobo Temporal , Epilepsia , Acidente Vascular Cerebral , Feminino , Humanos , Masculino , Estudos de Casos e Controles , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Transtornos Cerebrovasculares/patologia , Epilepsia/patologia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Imageamento por Ressonância Magnética/métodos , Esclerose/patologia , Acidente Vascular Cerebral/patologia , Adulto
7.
Stroke ; 53(2): 586-594, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34794335

RESUMO

BACKGROUND AND PURPOSE: Despite the advances in treating neonatal hypoxic-ischemic encephalopathy (HIE) with induced hypothermia, the rates of severe disability are still high among survivors. Preclinical studies have indicated that cell therapies with hematopoietic stem/progenitor cells could improve neurological outcomes in HIE. In this study, we investigated whether the administration of AMD3100, a CXCR4 antagonist that mobilizes hematopoietic stem/progenitor cells into the circulation, has therapeutic effects in HIE. METHODS: P10 Wistar rats of both sexes were subjected to right common carotid artery occlusion or sham procedure, and then were exposed to hypoxia for 120 minutes. Two subcutaneous injections of AMD3100 or vehicle were given on the third and fourth day after HIE. We first assessed the interindividual variability in brain atrophy after experimental HIE and vehicle treatment in a small cohort of rats. Based on this exploratory analysis, we designed and conducted an experiment to test the efficacy of AMD3100. Brain atrophy on day 21 after HIE was defined as the primary end point. Secondary efficacy end points were cognitive (T-water maze) and motor function (rotarod) on days 17 and 18 after HIE, respectively. RESULTS: AMD3100 did not decrease the brain atrophy in animals of either sex. Cognitive impairments were not observed in the T-water maze, but male hypoxic-ischemic animals exhibited motor coordination deficits on the rotarod, which were not improved by AMD3100. A separate analysis combining data from animals of both sexes also revealed no evidence of the effectiveness of AMD3100 treatment. CONCLUSIONS: These results indicate that the subacute treatment with AMD3100 does not improve structural and functional outcomes in a rat HIE model.


Assuntos
Benzilaminas/uso terapêutico , Ciclamos/uso terapêutico , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Receptores CXCR4/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Atrofia , Benzilaminas/administração & dosagem , Encéfalo/patologia , Disfunção Cognitiva/psicologia , Ciclamos/administração & dosagem , Determinação de Ponto Final , Feminino , Masculino , Aprendizagem em Labirinto , Gravidez , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Wistar , Caracteres Sexuais , Falha de Tratamento
8.
PLoS Pathog ; 16(8): e1008230, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797076

RESUMO

Neutrophil extracellular traps (NETs) evolved as a unique effector mechanism contributing to resistance against infection that can also promote tissue damage in inflammatory conditions. Malaria infection can trigger NET release, but the mechanisms and consequences of NET formation in this context remain poorly characterized. Here we show that patients suffering from severe malaria had increased amounts of circulating DNA and increased neutrophil elastase (NE) levels in plasma. We used cultured erythrocytes and isolated human neutrophils to show that Plasmodium-infected red blood cells release macrophage migration inhibitory factor (MIF), which in turn caused NET formation by neutrophils in a mechanism dependent on the C-X-C chemokine receptor type 4 (CXCR4). NET production was dependent on histone citrullination by peptidyl arginine deiminase-4 (PAD4) and independent of reactive oxygen species (ROS), myeloperoxidase (MPO) or NE. In vitro, NETs functioned to restrain parasite dissemination in a mechanism dependent on MPO and NE activities. Finally, C57/B6 mice infected with P. berghei ANKA, a well-established model of cerebral malaria, presented high amounts of circulating DNA, while treatment with DNAse increased parasitemia and accelerated mortality, indicating a role for NETs in resistance against Plasmodium infection.


Assuntos
Eritrócitos/imunologia , Armadilhas Extracelulares/imunologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Malária/imunologia , Neutrófilos/imunologia , Plasmodium/imunologia , Receptores CXCR4/metabolismo , Animais , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/parasitologia , Humanos , Malária/metabolismo , Malária/parasitologia , Malária/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Neutrófilos/parasitologia , Parasitemia/imunologia , Parasitemia/metabolismo , Parasitemia/parasitologia , Parasitemia/patologia
9.
Neurol Sci ; 43(7): 4381-4386, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35150351

RESUMO

INTRODUCTION: Cognitive impairment and retinal atrophy have been proposed as two potential markers of neurodegeneration in multiple sclerosis (MS). We aimed at assessing the relation between peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell layer (mGCL) atrophy and cognitive performance in early MS. METHODS: This is a multicenter cross-sectional study on patients with early MS (clinically isolated syndrome and relapsing-remitting MS), with an EDSS score ≤ 3.0. Patients with previous optic neuritis, other ocular diseases, psychiatric illness, or recent relapse were excluded. All patients underwent standardized optical coherence tomography (OCT) and neuropsychological evaluation with validated tests for MS patients. Cognitive impairment was defined as having two cognitive tasks below age- and education-adjusted norms. RESULTS: We recruited 52 patients with early MS, with an average age of 37 years (SD = 10.5), an average disease duration of 3.69 years (SD = 2.3), and a median EDSS of 1.0 (IQR = 0.5). In this sample, 15/52 patients presented cognitive impairment. Regarding OCT measurements, 7/52 patients had an average pRNFL below the 5th percentile and 2/52 had an average mGCL below the 5th percentile. The average pRNFL thickness was comparable in cognitively impaired and cognitively preserved patients (100.3 µm vs 103.1 µm, p = 0.52); the average mGCL thickness had also similar values between groups (50.5 µm vs 53 µm, p = 0.38). CONCLUSIONS: Cognitive impairment was frequent in our sample of early MS. However, no association with reduced pRNFL or mGCL thickness was found. When compared to OCT, cognitive assessment could provide an earlier marker of neurodegeneration in MS.


Assuntos
Disfunção Cognitiva , Esclerose Múltipla , Neurite Óptica , Adulto , Atrofia/patologia , Biomarcadores , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Estudos Transversais , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Neurite Óptica/patologia , Retina/patologia , Tomografia de Coerência Óptica/métodos
10.
Acta Neurochir (Wien) ; 164(8): 2021-2034, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35230551

RESUMO

BACKGROUND: Gliomas are typically considered to cause relatively few neurological impairments. However, cognitive difficulties can arise, for example during treatment, with potential detrimental effects on quality of life. Accurate, reproducible, and accessible cognitive assessment is therefore vital in understanding the effects of both tumor and treatments. Our aim is to compare traditional neuropsychological assessment with an app-based cognitive screening tool in patients with glioma before and after surgical resection. Our hypotheses were that cognitive impairments would be apparent, even in a young and high functioning cohort, and that app-based cognitive screening would complement traditional neuropsychological assessment. METHODS: Seventeen patients with diffuse gliomas completed a traditional neuropsychological assessment and an app-based touchscreen tablet assessment pre- and post-operatively. The app assessment was also conducted at 3- and 12-month follow-up. Impairment rates, mean performance, and pre- and post-operative changes were compared using standardized Z-scores. RESULTS: Approximately 2-3 h of traditional assessment indicated an average of 2.88 cognitive impairments per patient, while the 30-min screen indicated 1.18. As might be expected, traditional assessment using multiple items across the difficulty range proved more sensitive than brief screening measures in areas such as memory and attention. However, the capacity of the screening app to capture reaction times enhanced its sensitivity, relative to traditional assessment, in the area of non-verbal function. Where there was overlap between the two assessments, for example digit span tasks, the results were broadly equivalent. CONCLUSIONS: Cognitive impairments were common in this sample and app-based screening complemented traditional neuropsychological assessment. Implications for clinical assessment and follow-up are discussed.


Assuntos
Neoplasias Encefálicas , Transtornos Cognitivos , Glioma , Aplicativos Móveis , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Cognição , Transtornos Cognitivos/etiologia , Glioma/complicações , Glioma/diagnóstico , Glioma/cirurgia , Humanos , Testes Neuropsicológicos , Qualidade de Vida
11.
Stroke ; 52(5): 1788-1797, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33827248

RESUMO

Background and Purpose: Heme is a red blood cell component released in the brain parenchyma following intracerebral hemorrhage. However, the study of the pathophysiological mechanisms triggered by heme in the brain is hampered by the lack of well-established in vivo models of intracerebral heme injection. This study aims to optimize and characterize a protocol of intrastriatal heme injection in mice, with a focus on the induction of lipid peroxidation, neuroinflammation and, ultimately, sensorimotor deficits. We also evaluated the involvement of NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3), an inflammasome sensor, in the behavior deficits induced by heme in this model. Methods: Mice were injected with heme in the striatum for the evaluation of neuroinflammation and brain damage through histological and biochemical techniques. Immunoblot was used to evaluate the expression of proteins involved in heme/iron metabolism and antioxidant responses and the activation of the MAPK (mitogen-activated protein kinase) signaling pathway. For the assessment of neurological function, we followed-up heme-injected mice for 2 weeks using the rotarod, elevated body swing, and cylinder tests. Mice injected with the vehicle (sham), or autologous blood were used as controls. Results: Heme induced lipid peroxidation and inflammation in the brain. Moreover, heme increased the expression of HO-1 (heme oxygenase-1), ferritin, p62, and superoxide dismutase 2, and activated the MAPK signaling pathway promoting pro-IL (interleukin)-1ß production and its cleavage to the active form. Heme-injected mice exhibited signs of brain damage and reactive astrogliosis around the injection site. Behavior deficits were observed after heme or autologous blood injection in comparison to sham-operated controls. In addition, behavior deficits and IL-1ß production were reduced in Nlrp3 knockout mice in comparison to wild-type mice. Conclusions: Our results show that intracerebral heme injection induces neuroinflammation, and neurological deficits, in an NLRP3-dependent manner, suggesting that this is a feasible model to evaluate the role of heme in neurological disorders.


Assuntos
Comportamento Animal/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Heme/administração & dosagem , Peroxidação de Lipídeos/efeitos dos fármacos , Doenças Neuroinflamatórias/metabolismo , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Inflamassomos/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Neuroinflamatórias/patologia
12.
J Neurochem ; 158(3): 694-709, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34081777

RESUMO

Gangliosides are glycosphingolipids abundantly expressed in the vertebrate nervous system, and are classified into a-, b-, or c-series according to the number of sialic acid residues. The enzyme GD3 synthase converts GM3 (an a-series ganglioside) into GD3, a b-series ganglioside highly expressed in the developing and adult retina. The present study evaluated the visual system of GD3 synthase knockout mice (GD3s-/- ), morphologically and functionally. The absence of b- series gangliosides in the retinas of knockout animals was confirmed by mass spectrometry imaging, which also indicated an accumulation of a-series gangliosides, such as GM3. Retinal ganglion cell (RGC) density was significantly reduced in GD3s-/- mice, with a similar reduction in the number of axons in the optic nerve. Knockout animals also showed a 15% reduction in the number of photoreceptor nuclei, but no difference in the bipolar cells. The area occupied by GFAP-positive glial cells was smaller in GD3s-/- retinas, but the number of microglial cells/macrophages did not change. In addition to the morphological alterations, a 30% reduction in light responsiveness was detected through quantification of pS6-expressing RGC, an indicator of neural activity. Furthermore, electroretinography (ERG) indicated a significant reduction in RGC and photoreceptor electrical activity in GD3s-/- mice, as indicated by scotopic ERG and pattern ERG (PERG) amplitudes. Finally, evaluation of the optomotor response demonstrated that GD3s-/- mice have reduced visual acuity and contrast sensitivity. These results suggest that b-series gangliosides play a critical role in regulating the structure and function of the mouse visual system.


Assuntos
Sensibilidades de Contraste/fisiologia , Deleção de Genes , Retina/enzimologia , Sialiltransferases/deficiência , Sialiltransferases/genética , Acuidade Visual/fisiologia , Animais , Eletrorretinografia/métodos , Feminino , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Estimulação Luminosa/métodos
13.
Cell Tissue Res ; 385(3): 497-518, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34050823

RESUMO

The umbilical cord has been proved to be an easy-access, reliable, and useful source of mesenchymal stem cells (MSC) for clinical applications due to its primitive, immunomodulatory, non-immunogenic, secretory and paracrine, migratory, proliferative, and multipotent properties. This set of characteristics has recently attracted great research interest in the fields of nanotechnology and regenerative medicine and cellular therapy. Accumulating evidence supports a pronounced therapeutic potential of MSC in many different pathologies, from hematology to immunology, wound-healing, tissue regeneration, and oncology. Diabetes mellitus, branded the epidemic of the century, is considered a chronic metabolic disorder, representing a major burden for health system sustainability and an important public health challenge to modern societies. The available treatments for type 2 diabetes mellitus (T2DM) still rely mainly on combinations of oral antidiabetic agents with lifestyle and nutritional adjustments. Despite the continuous development of novel and better hypoglycemic drugs, their efficacy is limited in the installment and progression of silent T2DM complications. T2DM comorbidities and mortality rates still make it a serious, common, costly, and long-term manageable disease. Recently, experimental models, preclinical observations, and clinical studies have provided some insights and preliminary promising results using umbilical cord MSCs to treat and manage diabetes. This review focuses on the latest research and applications of human-derived umbilical cord MSC in the treatment and management of T2DM, exploring and systematizing the key effects of both umbilical cord MSC and its factor-rich secretome accordingly with the major complications associated to T2DM.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Humanos
14.
Artigo em Inglês | MEDLINE | ID: mdl-33751181

RESUMO

In terrestrial legged locomotion, the distribution of mass can influence the gait characteristics. This can be due to a change in the magnitude or distribution of the load. The latter occurs in scorpions when they lift their large metasoma from a trailing position in ambulatory posture to the well-known arched forward position in the defensive posture. We measured how locomotion changes between these two postures by recording scorpions walking using high-speed video. We found that the metasoma in the fat-tailed scorpion (Androctonus australis) represents about a quarter of the total mass. Moving this mass anteriorly over the body changes the position of the center of mass forward 8.15 ± 1.86 mm. We found this increases the overall duty factor, and particularly that of the second leg pair, even when taking the reduced speed in defensive posture into account. In the five scorpions we recorded, also the ipsilateral phase of leg pairs 3 and 4 differed in defensive posture. We found that the trajectory the 4th foot describes during a single stride also differed significantly between postures, showing this to be a sensitive measure of changes in gait. The change from an ambulatory to a defensive posture places different demands on the gait of scorpions, possibly largely due to the forward displacement of the center of mass.


Assuntos
Marcha/fisiologia , Postura/fisiologia , Escorpiões/fisiologia , Somatotipos/fisiologia , Cauda/fisiologia , Animais , Feminino , Masculino , Escorpiões/anatomia & histologia , Cauda/anatomia & histologia , Gravação em Vídeo/métodos
15.
Neurol Sci ; 42(6): 2515-2517, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33462633

RESUMO

Transient global amnesia (TGA) is a neurological syndrome with rather distinctive brain MRI features, namely hyperintense lesion in hippocampus on diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) sequences. Post-traumatic amnesia is another amnestic syndrome which can also show hyperintense lesions in brain MRI due to cytotoxic oedema caused by traumatic brain injury. We present a case of a patient with post-traumatic amnesia with a brain MRI image mimic of TGA.


Assuntos
Amnésia Global Transitória , Amnésia/diagnóstico por imagem , Amnésia Global Transitória/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem
16.
Retina ; 41(3): 555-562, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32604342

RESUMO

PURPOSE: To correlate drusen morphology and outer retinal status with autofluorescence (AF) imaging in patients with intermediate age-related macular degeneration. METHODS: Drusen type and morphology were analyzed using color fundus photography and spectral-domain optic coherence tomography, whereas fundus AF was used for drusen AF evaluation. Additional structural changes on spectral-domain optic coherence tomography, such as disruption of external limiting membrane, ellipsoid zone, and retinal pigment epithelium/Bruch membrane complex, as well as the presence of choroidal hypertransmission at correspondent locations were also evaluated and correlated with fundus AF findings. Spearman's correlation coefficient was used to analyze the correlation between spectral-domain optic coherence tomography morphological characteristics of drusen and AF appearance of the corresponding drusen. Strength of correlation was calculated (r), and a P value < 0.05 was considered statistically significant. RESULTS: Two hundred and twenty-eight drusen from 53 eyes of 53 patients were analyzed, 130 soft drusen (57.02%) and 98 cuticular drusen (42.98%). Sixty percent of the drusen were isoautofluorescent (n = 136), 35% hyperautofluorescent (n = 80), and 5% hypoautofluorescent (n = 12). We found positive correlation between drusen AF and hyperreflective foci (r = 0.4). Outer retinal layers morphology (external limiting membrane and ellipsoid zone status and hypertransmission) also correlates with autofluorescent findings (r = 0.3). CONCLUSION: Multimodal imaging reveals a broad spectrum of ultrastructural changes, which may reflect different stages in the evolution of drusen. Our results suggest that drusen morphological characteristics and autofluorescent findings are correlated but other factors or cofactors may be involved. The described correlations will help us understand new progression biomarkers of nonexudative age-related macular degeneration.


Assuntos
Angiofluoresceinografia/métodos , Oftalmoscopia/métodos , Imagem Óptica , Drusas Retinianas/diagnóstico , Epitélio Pigmentado da Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Acta Neurochir (Wien) ; 163(5): 1299-1309, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33222010

RESUMO

BACKGROUND: Intraoperative functional mapping with direct electrical stimulation during awake surgery for patients with diffuse low-grade glioma has been used in recent years to optimize the balance between surgical resection and quality of life following surgery. Mapping of executive functions is particularly challenging because of their complex nature, with only a handful of reports published so far. Here, we propose the recording of neural activity directly from the surface of the brain using electrocorticography to map executive functions and demonstrate its feasibility and potential utility. METHODS: To track a neural signature of executive function, we recorded neural activity using electrocorticography during awake surgery from the frontal cortex of three patients judged to have an appearance of diffuse low-grade glioma. Based on existing functional magnetic resonance imaging (fMRI) evidence from healthy participants for the recruitment of areas associated with executive function with increased task demands, we employed a task difficulty manipulation in two counting tasks performed intraoperatively. Following surgery, the data were extracted and analyzed offline to identify increases in broadband high-gamma power with increased task difficulty, equivalent to fMRI findings, as a signature of activity related to executive function. RESULTS: All three patients performed the tasks well. Data were recorded from five electrode strips, resulting in data from 15 channels overall. Eleven out of the 15 channels (73.3%) showed significant increases in high-gamma power with increased task difficulty, 26.6% of the channels (4/15) showed no change in power, and none of the channels showed power decrease. High-gamma power increases with increased task difficulty were more likely in areas that are within the canonical frontoparietal network template. CONCLUSIONS: These results are the first step toward developing electrocorticography as a tool for mapping of executive function complementarily to direct electrical stimulation to guide resection. Further studies are required to establish this approach for clinical use.


Assuntos
Mapeamento Encefálico , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Eletrocorticografia , Função Executiva , Glioma/fisiopatologia , Glioma/cirurgia , Cuidados Intraoperatórios , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Cognição/fisiologia , Estimulação Elétrica , Feminino , Ritmo Gama/fisiologia , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Qualidade de Vida
18.
J Card Surg ; 36(6): 2143-2145, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33651415

RESUMO

The endometrial stromal sarcoma (EES) is a rare uterine malignancy and its intracardiac metastasis are exceedingly rare. We report a case of a 53-year-old female patient diagnosed with a metastatic tumor of a ESS in the right side of the heart, who underwent successful surgical resection and initiated chemotherapy with docetaxel and gemcitabine. At a 9-month follow-up, the patient was in New York Heart Association-Class I, without any further complications.


Assuntos
Neoplasias do Endométrio , Neoplasias Cardíacas , Sarcoma do Estroma Endometrial , Feminino , Coração , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/cirurgia , Humanos , Pessoa de Meia-Idade , Sarcoma do Estroma Endometrial/cirurgia
19.
Mov Disord ; 39(3): 485, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38362826
20.
Crit Care ; 22(1): 249, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290827

RESUMO

BACKGROUND: Ischemic stroke causes brain inflammation, which we postulate may result in lung damage. Several studies have focused on stroke-induced immunosuppression and lung infection; however, the possibility that strokes may trigger lung inflammation has been overlooked. We hypothesized that even focal ischemic stroke might induce acute systemic and pulmonary inflammation, thus altering respiratory parameters, lung tissue integrity, and alveolar macrophage behavior. METHODS: Forty-eight Wistar rats were randomly assigned to ischemic stroke (Stroke) or sham surgery (Sham). Lung function, histology, and inflammation in the lung, brain, bronchoalveolar lavage fluid (BALF), and circulating plasma were evaluated at 24 h. In vitro, alveolar macrophages from naïve rats (unstimulated) were exposed to serum or BALF from Sham or Stroke animals to elucidate possible mechanisms underlying alterations in alveolar macrophage phagocytic capability. Alveolar macrophages and epithelial and endothelial cells of Sham and Stroke animals were also isolated for evaluation of mRNA expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α. RESULTS: Twenty-four hours following ischemic stroke, the tidal volume, expiratory time, and mean inspiratory flow were increased. Compared to Sham animals, the respiratory rate and duty cycle during spontaneous breathing were reduced, but this did not affect lung mechanics during mechanical ventilation. Lungs from Stroke animals showed clear evidence of increased diffuse alveolar damage, pulmonary edema, and inflammation markers. This was associated with an increase in ultrastructural damage, as evidenced by injury to type 2 pneumocytes and endothelial cells, cellular infiltration, and enlarged basement membrane thickness. Protein levels of proinflammatory mediators were documented in the lung, brain, and plasma (TNF-α and IL-6) and in BALF (TNF-α). The phagocytic ability of macrophages was significantly reduced. Unstimulated macrophages isolated from naïve rats only upregulated expression of TNF-α and IL-6 following exposure to serum from Stroke rats. Exposure to BALF from Stroke or Sham animals did not change alveolar macrophage behavior, or gene expression of TNF-α and IL-6. IL-6 expression was increased in macrophages and endothelial cells from Stroke animals. CONCLUSIONS: In rats, focal ischemic stroke is associated with brain-lung crosstalk, leading to increased pulmonary damage and inflammation, as well as reduced alveolar macrophage phagocytic capability, which seems to be promoted by systemic inflammation.


Assuntos
Lesão Pulmonar/etiologia , Macrófagos Alveolares/patologia , Fagócitos/patologia , Acidente Vascular Cerebral/complicações , Animais , Isquemia Encefálica/complicações , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Terapia de Imunossupressão/efeitos adversos , Interleucina-6/análise , Interleucina-6/sangue , Lesão Pulmonar/sangue , Lesão Pulmonar/patologia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/veterinária , RNA Mensageiro/análise , RNA Mensageiro/sangue , Ratos , Ratos Wistar/imunologia , Ratos Wistar/metabolismo , Estatísticas não Paramétricas , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/fisiopatologia , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/sangue
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