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1.
Brain Pathol ; 29(5): 675-692, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31106489

RESUMO

Multiple Sclerosis is an autoimmune disorder causing neurodegeneration mostly in young adults. Thereby, myelin is lost in the inflammatory lesions leaving unmyelinated axons at a high risk to degenerate. Oligodendrocyte precursor cells maintain their regenerative capacity into adulthood and are able to remyelinate axons if they are properly activated and differentiate. Neuronal activity influences the success of myelination indicating a close interplay between neurons and oligodendroglia. The myelination profile determines the distribution of voltage-gated ion channels along the axon. Here, we analyze the distribution of the sodium channel subunit Nav1.6 and the ultrastructure of axons after cuprizone-induced demyelination in transgenic mice expressing GFP in oligodendroglial cells. Using this mouse model, we found an increased number of GFP-expressing oligodendroglial cells compared to untreated mice. Analyzing the axons, we found an increase in the number of nodes of Ranvier in mice that had received cuprizone. Furthermore, we found an enhanced portion of unmyelinated axons showing vesicles in the cytoplasm. These vesicles were labeled with VGlut1, indicating that they are involved in axonal signaling. Our results highlight the flexibility of axons towards changes in the glial compartment and depict the structural changes they undergo upon myelin removal. These findings might be considered if searching for new neuroprotective therapies that aim at blocking neuronal activity in order to avoid interfering with the process of remyelination.

2.
Mod Pathol ; 32(8): 1123-1134, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30952970

RESUMO

Angioimmunoblastic T-cell lymphoma is a peripheral T-cell lymphoma derived from follicular T-helper cells. High-throughput genomic sequencing studies have shown that angioimmunoblastic T-cell lymphoma carries frequent mutations in RHOAG17V and IDH2R172 genes. The clinico-pathological features of angioimmunoblastic T-cell lymphoma cases with RHOAG17V mutations have been addressed; however, similar studies for IDH2 mutated cases are lacking. Therefore, the aim of the present study was to evaluate the pathological features of angioimmunoblastic T-cell lymphoma with IDH2 mutations. In order to identify cases with IDH2 mutations, 50 cases previously diagnosed as angioimmunoblastic T-cell lymphoma were subjected to next-generation sequencing analysis using a custom panel covering four genes frequently mutated in angioimmunoblastic T-cell lymphoma including DNMT3A, TET2, IDH2 and RHOA. All cases were analyzed for PD1, ICOS, CXCL13, CD10, BCL6, CD21, CD23 and EBER in situ hybridization. Mutational analysis recognized three groups. Group 1: IDH2R172 mutations were identified in 20 cases (40%). All cases carried RHOAG17V mutations. Group 2: RHOAG17V mutations without IDH2R172 mutation were identified in 16 cases (32%), and Group 3: 14 cases (28%) without RHOAG17V or IDH2R172 mutations. Morphologically, angioimmunoblastic T-cell lymphoma cases with IDH2R172 mutations were characterized by the presence of medium to large clear cells (p = 0.00001), and a follicular T-helper phenotype with the particular feature of strong CD10 (p = 0.0268) and CXCL13 expression (p = 0.0346). Interestingly, TET2 mutations were identified in 32 of 33 (97%) cases with IDH2R172 and/or RHOAG17V mutations whereas only 55% of angioimmunoblastic T-cell lymphoma cases wild-type for these two genes carried TET2 mutations (p = 0.0022). In contrast, DNMT3A mutations were found in 48% of the cases and were equally distributed in the three groups. In conclusion, our results support the results of gene expression profiling studies suggesting that IDH2R172 mutations define a unique subgroup within angioimmunoblastic T-cell lymphoma with strong follicular T-helper-like phenotype and characteristic morphological features.

3.
Sci Rep ; 9(1): 4391, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867516

RESUMO

LiCuVO4 is a model system of a 1D spin-1/2 chain that enters a planar spin-spiral ground state below its Néel temperature of 2.4 K due to competing nearest and next nearest neighbor interactions. The spin-spiral state is multiferroic with an electric polarization along the a axis which has been proposed to be caused purely by the spin supercurrent mechanism. With external magnetic fields in c direction TN can be suppressed down to 0 K at 7.4 T. Here we report dynamical measurements of the polarization from P(E)-hysteresis loops, magnetic field dependent pyro-current and non-linear dielectric spectroscopy as well as thermal expansion and magnetostriction measurements at very low temperatures. The multiferroic transition is accompanied by strong anomalies in the thermal expansion and magnetostriction coefficients and we find slow switching times of electric domain reversal. Both observations suggest a sizable magnetoelastic coupling in LiCuVO4. By analyzing the non-linear polarization dynamics we derive domain sizes in the nm range that are probably caused by Li defects.

4.
Neurochem Int ; 126: 139-153, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30867127

RESUMO

Brain-intrinsic degenerative cascades are a proposed factor driving inflammatory lesion formation in multiple sclerosis (MS) patients. We recently showed that encephalitogenic lymphocytes are recruited to the sites of active demyelination induced by cuprizone. Here, we investigated whether cuprizone-induced oligodendrocyte and myelin pathology is sufficient to trigger peripheral immune cell recruitment into the forebrain. We show that early cuprizone-induced white matter lesions display a striking similarity to early MS lesions, i.e., oligodendrocyte degeneration, microglia activation and absence of severe lymphocyte infiltration. Such early cuprizone lesions are sufficient to trigger peripheral immune cell recruitment secondary to subsequent EAE (experimental autoimmune encephalomyelitis) induction. The lesions are characterized by discontinuation of the perivascular glia limitans, focal axonal damage, and perivascular astrocyte pathology. Time course studies showed that the severity of cuprizone-induced lesions positively correlates with the extent of peripheral immune cell recruitment. Furthermore, results of genome-wide array analyses suggest that moesin is integral for early microglia activation in cuprizone and MS lesions. This study underpins the significance of brain-intrinsic degenerative cascades for immune cell recruitment and, in consequence, MS lesion formation.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Imunidade Celular/fisiologia , Microglia/imunologia , Oligodendroglia/imunologia , Prosencéfalo/imunologia , Animais , Cuprizona/toxicidade , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/patologia , Feminino , Imunidade Celular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/patologia , Esclerose Múltipla/induzido quimicamente , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Glicoproteína Mielina-Oligodendrócito/toxicidade , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/patologia , Fragmentos de Peptídeos/toxicidade , Prosencéfalo/efeitos dos fármacos , Prosencéfalo/patologia
5.
FASEB J ; 33(4): 5312-5319, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30645152

RESUMO

Claudins (cldns) represent the largest family of transmembrane tight junction (TJ) proteins, determining organ-specific epithelial barrier properties. Because methods for the analysis of multiple cldn interaction are limited, we have established the heterologous Xenopus laevis oocyte expression system for TJ protein assembly and interaction analysis. Oocytes were injected with cRNA encoding human cldn-1, -2, or -3 or with a combination of these and were incubated in pairs for interaction analysis. Immunoblotting and immunohistochemistry were performed, and membrane contact areas were analyzed morphometrically and by freeze fracture electron microscopy. Cldns were specifically detected in membranes of expressing oocytes, and coincubation of oocytes resulted in adhesive contact areas that increased with incubation time. Adjacent membrane areas revealed specific cldn signals, including "kissing-point"-like structures representing homophilic trans-interactions of cldns. Contact areas of oocytes expressing a combination markedly exceeded those expressing single cldns, indicating effects on adhesion. Ultrastructural analysis revealed a self-assembly of TJ strands and a cldn-specific strand morphology.-Vitzthum, C., Stein, L., Brunner, N., Knittel, R., Fallier-Becker, P., Amasheh, S. Xenopus oocytes as a heterologous expression system for analysis of tight junction proteins.


Assuntos
Membrana Celular/metabolismo , Oócitos/metabolismo , Proteínas de Junções Íntimas/metabolismo , Animais , Claudina-1/genética , Claudina-1/metabolismo , Claudina-2/genética , Claudina-2/metabolismo , Claudina-3/genética , Claudina-3/metabolismo , Técnica de Fratura por Congelamento , Humanos , Immunoblotting , Imuno-Histoquímica , Microscopia Eletrônica , Ligação Proteica , Proteínas de Junções Íntimas/genética , Xenopus laevis
6.
Acad Radiol ; 26(2): 247-256, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29731419

RESUMO

RATIONALE AND OBJECTIVES: This study aimed to test the hypothesis that ultrastructural wall abnormalities of lymphoma vessels correlate with perfusion computed tomography (PCT) kinetics. MATERIALS AND METHODS: Our local institutional review board approved this prospective study. Between February 2013 and June 2016, we included 23 consecutive subjects with newly diagnosed lymphoma, who were referred for computed tomography-guided biopsy (6 women, 17 men; mean age, 60.61 ± 12.43 years; range, 28-74 years) and additionally agreed to undergo PCT of the target lymphoma tissues. PCT was obtained for 40 seconds using 80 kV, 120 mAs, 64 × 0.6-mm collimation, 6.9-cm z-axis coverage, and 26 volume measurements. Mean and maximum k-trans (mL/100 mL/min), blood flow (BF; mL/100 mL/min) and blood volume (BV) were quantified using the deconvolution and the maximum slope + Patlak calculation models. Immunohistochemical staining was performed for microvessel density quantification (vessels/m2), and electron microscopy was used to determine the presence or absence of tight junctions, endothelial fenestration, basement membrane, and pericytes, and to measure extracellular matrix thickness. RESULTS: Extracellular matrix thickness as well as the presence or absence of tight junctions, basal lamina, and pericytes did not correlate with computed tomography perfusion parameters. Endothelial fenestrations correlated significantly with mean BFdeconvolution (P = .047, r = 0.418) and additionally was significantly associated with higher mean BVdeconvolution (P < .005). Mean k-transPatlak correlated strongly with mean k-transdeconvolution (r = 0.939, P = .001), and both correlated with mean BFdeconvolution (P = .001, r = 0.748), max BFdeconvolution (P = .028, r = 0.564), mean BVdeconvolution (P = .001, r = 0.752), and max BVdeconvolution (P = .001, r = 0.771). Microvessel density correlated with max k-transdeconvolution (r = 0.564, P = .023). Vascular endothelial growth factor receptor-3 expression (receptor specific for lymphatics) correlated significantly with max k-transPatlak (P = .041, r = 0.686) and mean BFdeconvolution (P = .038, r = 0.695). CONCLUSION: k-Trans values of PCT do not correlate with ultrastructural microvessel features, whereas endothelial fenestrations correlate with increased intra-tumoral BVs.


Assuntos
Linfoma , Microvasos/ultraestrutura , Imagem de Perfusão/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Correlação de Dados , Feminino , Humanos , Imuno-Histoquímica , Linfoma/metabolismo , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/irrigação sanguínea , Estudos Prospectivos
7.
Sci Rep ; 8(1): 15002, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30302029

RESUMO

The flagellated parasite Trypanosoma brucei is the causative agent of Human African Trypanosomiasis (HAT). By a mechanism not well understood yet, trypanosomes enter the central nervous system (CNS), invade the brain parenchyma, and cause a fatal encephalopathy if is not treated. Trypanosomes are fast dividing organisms that, without any immune response, would kill the host in a short time. However, infected individuals survive either 6-12 months or more than 3 years for the acute and chronic forms, respectively. Thus, only when the brain defense collapses a lethal encephalopathy will occur. Here, we evaluated interactions between trypanosomes and microglial cells, which are the primary immune effector cells within the CNS. Using co-cultures of primary microglia and parasites, we found clear evidences of trypanosome phagocytosis by microglial cells. Microglia activation was also evident; analysis of its ultrastructure showed changes that have been reported in activated microglia undergoing oxidative stress caused by infections or degenerative diseases. Accordingly, an increase of the nitric oxide production was detected in supernatants of microglia/parasite co-cultures. Altogether, our results demonstrate that microglial cells respond to the presence of the parasite, leading to parasite's engulfment and elimination.


Assuntos
Encefalopatias/metabolismo , Microglia/metabolismo , Trypanosoma brucei brucei/metabolismo , Tripanossomíase Africana/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/parasitologia , Encéfalo/patologia , Encefalopatias/complicações , Encefalopatias/parasitologia , Encefalopatias/patologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/parasitologia , Sistema Nervoso Central/patologia , Técnicas de Cocultura , Humanos , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Microglia/parasitologia , Microglia/patologia , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Estresse Oxidativo , Fagocitose/genética , Trypanosoma brucei brucei/patogenicidade , Tripanossomíase Africana/parasitologia , Tripanossomíase Africana/patologia
8.
Leuk Res ; 71: 47-54, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30005184

RESUMO

Despite the high prevalence of central nervous system (CNS) involvement in relapsing pediatric acute lymphoblastic leukemia (ALL), our understanding of CNS invasion is still vague. As lymphoblasts have to overcome the physiological blood-CNS barriers to enter the CNS, we investigated the cellular interactions of lymphoblasts with the choroid plexus (CP) epithelium of the blood-cerebrospinal fluid barrier (BCSFB). Both a precurser B cell ALL (pB-ALL) cell line (SD-1) and a T cell ALL (T-ALL) cell line (P12-Ishikawa) were able to actively cross the CP epithelium in a human in vitro model. We could illustrate a transcellular and (supposedly) paracellular transmigration by 3-dimensional immunofluorescence microscopy as well as electron microscopy. Chemotactic stimulation with CXCL12 during this process led to a significantly increased transmigration and blocking CXCL12/CXCR4-signaling by the CXCR4-inhibitor AMD3100 inhibited this effect. However, CXCR4 expression in primary ALL samples did not correlate to CNS disease, indicating that CXCR4-driven CNS invasion across the BCSFB might be a general property of pediatric ALL. Notably, we present a unique in vitro BCSFB model suitable to study CNS invasion of lymphoblasts in a human setting, providing the opportunity to investigate experimental variables, which may determine CNS disease childhood ALL.


Assuntos
Plexo Corióideo , Linfócitos/metabolismo , Invasividade Neoplásica/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Migração Transendotelial e Transepitelial/fisiologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Quimiocina CXCL12/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Técnicas In Vitro , Linfócitos/patologia , Masculino , Modelos Biológicos , Receptores CXCR4/metabolismo , Células Tumorais Cultivadas
9.
J Phys Condens Matter ; 30(29): 295403, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29869988

RESUMO

The compound [Formula: see text] is magnetoelectric but not multiferroic with an erythrosiderite-related structure. We present a comprehensive investigation of its structural and antiferromagnetic phase transitions by polarization microscopy, pyroelectric measurements, x-ray diffraction and neutron diffraction. At about [Formula: see text] K, the compound changes its symmetry from Cmcm to I2/c, with a doubling of the original c-axis. This transformation is associated with rotations of the [Formula: see text] octahedra and corresponds to an ordering of the [Formula: see text] molecules and of the related [Formula: see text] bonds. A significant ferroelectric polarization can be excluded for this transition by precise pyrocurrent measurements. The antiferromagnetic phase transition occurring at [Formula: see text] results in the magnetic space group [Formula: see text], which perfectly agrees with previous measurements of the linear magnetoelectric effect and magnetization.

10.
J Neuroinflammation ; 15(1): 50, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29463289

RESUMO

BACKGROUND: Echovirus (E) 30 (E-30) meningitis is characterized by neuroinflammation involving immune cell pleocytosis at the protective barriers of the central nervous system (CNS). In this context, infection of the blood-cerebrospinal fluid barrier (BCSFB), which has been demonstrated to be involved in enteroviral CNS pathogenesis, may affect the tight junction (TJ) and adherens junction (AJ) function and morphology. METHODS: We used an in vitro human choroid plexus epithelial (HIBCPP) cell model to investigate the effect of three clinical outbreak strains (13-311, 13-759, and 14-397) isolated in Germany in 2013, and compared them to E-30 Bastianni. Conducting transepithelial electrical resistance (TEER), paracellular dextran flux measurement, quantitative real-time polymerase chain reaction (qPCR), western blot, and immunofluorescence analysis, we investigated TJ and AJ function and morphology as well as strain-specific E-30 infection patterns. Additionally, transmission electron and focused ion beam microscopy electron microscopy (FIB-SEM) was used to evaluate the mode of leukocyte transmigration. Genome sequencing and phylogenetic analyses were performed to discriminate potential genetic differences among the outbreak strains. RESULTS: We observed a significant strain-dependent decrease in TEER with strains E-30 Bastianni and 13-311, whereas paracellular dextran flux was only affected by E-30 Bastianni. Despite strong similarities among the outbreak strains in replication characteristics and particle distribution, strain 13-311 was the only outbreak isolate revealing comparable disruptive effects on TJ (Zonula Occludens (ZO) 1 and occludin) and AJ (E-cadherin) morphology to E-30 Bastianni. Notwithstanding significant junctional alterations upon E-30 infection, we observed both para- and transcellular leukocyte migration across HIBCPP cells. Complete genome sequencing revealed differences between the strains analyzed, but no explicit correlation with the observed strain-dependent effects on HIBCPP cells was possible. CONCLUSION: The findings revealed distinct E-30 strain-specific effects on barrier integrity and junctional morphology. Despite E-30-induced barrier alterations leukocyte trafficking did not exclusively occur via the paracellular route.


Assuntos
Barreira Hematoencefálica/virologia , Líquido Cefalorraquidiano/virologia , Plexo Corióideo/virologia , Surtos de Doenças , Enterovirus Humano B/isolamento & purificação , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/ultraestrutura , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Células Cultivadas , Líquido Cefalorraquidiano/metabolismo , Plexo Corióideo/metabolismo , Plexo Corióideo/ultraestrutura , Enterovirus Humano B/metabolismo , Humanos , Filogenia , Especificidade da Espécie
11.
Crit Care Med ; 46(1): e91-e94, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29252954

RESUMO

OBJECTIVE: The objective of this report of a fatal propofol-related infusion syndrome in a young adult was to present-to our knowledge for the first time-direct ultrastructural evidence for the central role of mitochondrial damage in the pathogenesis of this syndrome. DATA SOURCES: Histological and electron microscopical analysis of liver, skeletal, and heart muscle obtained by autopsy and blood obtained from patient. STUDY SELECTION: Case report. DATA EXTRACTION: In addition to conventional macroscopical and histological investigations, electron-microscopical analysis of myocardial- and skeletal muscle and liver tissue obtained at autopsy from a young man was performed in order to search for ultrastructural changes of mitochondria. Acylcarnitine concentrations of his blood were determined by ultra-high performance liquid chromatography mass spectrometry. DATA SYNTHESIS: A 19-year-old male was admitted with acute left-side hemiparesis. The patient was intubated, then propofol infusion started, and a craniotomy was performed to remove an intracerebral hematoma. In the postoperative period, the patient presented with elevated intracranial pressure and brain edema. After repeat surgery, the patient showed impaired systolic left ventricular function, increasing fever, anuria, hyperkalemia, and metabolic acidosis, and he finally expired. Electron microscopy revealed dark, electron dense amorphous structures associated with mitochondria in heart muscle and liver tissue obtained at autopsy. Peripheral blood analysis revealed increased levels of acetyl-, propionyl-, butyryl-, malonyl-, and valeryl-carnitine as an indicator for propofol-related infusion syndrome, as well as for propofol-mediated inhibition of free fatty acid uptake into mitochondria, affecting beta-oxidation. CONCLUSIONS: Electron dense bodies found in association with mitochondria in muscle and liver cells probably correspond to accumulation of free fatty acid provide direct morphological evidence for the mitochondrial damage in propofol-related infusion syndrome.


Assuntos
Doenças Mitocondriais/induzido quimicamente , Doenças Mitocondriais/patologia , Síndrome da Infusão de Propofol/patologia , Carnitina/análogos & derivados , Carnitina/sangue , Craniotomia , Hematoma Subdural Intracraniano/cirurgia , Humanos , Infusões Intravenosas , Masculino , Microscopia Eletrônica , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/patologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/patologia , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/patologia , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/patologia , Adulto Jovem
12.
Neurourol Urodyn ; 37(1): 89-98, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28370277

RESUMO

AIMS: To explore the ultrastructure of interstitial cells in the upper lamina propria of the human bladder, to describe the spatial relationships and to investigate cell-cell contacts. METHODS: Focused ion beam scanning electron microscopy (FIB-SEM), 3-View SEM and confocal laser scanning microscopy were used to analyze the 3D ultrastructure of the upper lamina propria in male and female human bladders. RESULTS: 3View-SEM image stacks as large as 59 × 59 × 17 µm3 (xyz) at a resolution of 16 × 16 × 50 nm3 and high resolution (5 × 5 × 10 nm3 ) FIB-SEM stacks could be analyzed. Interstitial cells with myoid differentiation (mIC) and fibroblast like interstitial cells (fIC) were the major cell types in the upper lamina propria. The flat, sheet-like ICs were oriented strictly parallel to the urothelium. No spindle shaped cells were present. We furthermore identified one branched cell (bIC) with several processes contacting urothelial cells by penetrating the basal membrane. This cell did not make any contacts to other ICs within the upper lamina propria. We found no evidence for the occurrence of telocytes in the upper lamina propria. CONCLUSIONS: Comprehensive 3D-ultrastructural analysis of the human bladder confirmed distinct subtypes of interstitial cells. We provide evidence for a foremost unknown direct connection between a branched interstitial cell and urothelial cells of which the functional role has still to be elucidated. 3D-ultrastructure analyses at high resolution are needed to further define the subpopulations of lamina propria cells and cell-cell interactions.


Assuntos
Células Epiteliais/ultraestrutura , Junções Intercelulares/ultraestrutura , Microscopia/métodos , Membrana Mucosa/ultraestrutura , Bexiga Urinária/ultraestrutura , Urotélio/ultraestrutura , Células Epiteliais/citologia , Feminino , Humanos , Imageamento Tridimensional , Imuno-Histoquímica , Masculino , Microscopia Confocal , Microscopia Eletrônica de Varredura , Membrana Mucosa/citologia , Bexiga Urinária/citologia , Urotélio/citologia
13.
Horm Metab Res ; 49(11): 892-898, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29136677

RESUMO

Type 1 diabetes (T1D) during pregnancy possibly affects the development of the thymus and the maturation of the immune system in the offspring. The aim of the ImmunDiabRisk study was to investigate thymus growth and maternal and fetal immune responses in pregnancies with and without T1D. The thymus circumferences of the fetuses of pregnant women with T1D (n=49) and without diabetes (n=59) were measured using ultrasound around the 29th gestational week and standardized for gestational age. Simultaneously, the frequencies and total numbers of cell markers were analyzed by flow cytometry in maternal peripheral blood, and at birth in umbilical cord blood. The standardized circumference of the thymus was similar in fetuses of mothers with and without T1D (p=0.26). We observed higher numbers of FOXP3 Tregs, memory Tregs, erythrocytes, and lymphocytes in the cord blood from T1D pregnancies (p=0.01, p=0.002, p=0.002 and p=0.02, respectively). The frequencies of CD4+/CD8+ T cells correlated positively in maternal blood and umbilical cord blood of mother-child pairs, as did the levels of neutrophils (Spearman's correlation coefficient r=0.43, p=0.02 for CD4+/CD8+ cells; r=0.46, p=0.03 for neutrophils), while no significant correlations were observed between thymus circumference and any cell markers in the child. Parts of the prenatal immune system seem to develop differently in the offspring of mothers with and without T1D. The correlation of Tregs between maternal blood and cord blood may indicate a significant cross-talk between the maternal and fetal immune system.


Assuntos
Diabetes Gestacional/imunologia , Feto/imunologia , Imunidade , Timo/crescimento & desenvolvimento , Peso ao Nascer , Células Sanguíneas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Feminino , Sangue Fetal/metabolismo , Idade Gestacional , Humanos , Recém-Nascido , Mães , Tamanho do Órgão , Gravidez , Estatísticas não Paramétricas
15.
Glia ; 65(12): 1900-1913, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28836302

RESUMO

Brain-intrinsic degenerative cascades are a proposed factor driving inflammatory lesion formation in multiple sclerosis (MS) patients. We recently described a model combining noninflammatory cytodegeneration (via cuprizone) with the classic active experimental autoimmune encephalomyelitis (Cup/EAE model), which exhibits inflammatory forebrain lesions. Here, we describe the histopathological characteristics and progression of these Cup/EAE lesions. We show that inflammatory lesions develop at various topographical sites in the forebrain, including white matter tracts and cortical and subcortical grey matter areas. The lesions are characterized by focal demyelination, discontinuation of the perivascular glia limitans, focal axonal damage, and neutrophil granulocyte extravasation. Transgenic mice with enhanced green fluorescent protein-expressing microglia and red fluorescent protein-expressing monocytes reveal that both myeloid cell populations contribute to forebrain inflammatory infiltrates. EAE-triggered inflammatory cerebellar lesions were augmented in mice pre-intoxicated with cuprizone. Gene expression studies suggest roles of the chemokines Cxcl10, Ccl2, and Ccl3 in inflammatory lesion formation. Finally, follow-up experiments in Cup/EAE mice with chronic disease revealed that forebrain, but not spinal cord, lesions undergo spontaneous reorganization and repair. This study underpins the significance of brain-intrinsic degenerative cascades for immune cell recruitment and, in consequence, MS lesion formation.


Assuntos
Progressão da Doença , Encefalite/etiologia , Encefalite/patologia , Encefalomielite Autoimune Experimental/complicações , Sesquiterpenos/toxicidade , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Encefalite/genética , Encefalomielite Autoimune Experimental/imunologia , Feminino , Adjuvante de Freund/toxicidade , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Proteína Glial Fibrilar Ácida/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/patologia , Microglia/ultraestrutura , Monócitos/patologia , Monócitos/ultraestrutura , Glicoproteína Mielina-Oligodendrócito/imunologia , Glicoproteína Mielina-Oligodendrócito/toxicidade , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/toxicidade , Receptores CCR2/genética , Receptores CCR2/metabolismo , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8A/metabolismo
16.
Opt Lett ; 42(12): 2275-2278, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28614330

RESUMO

We studied the refractive index and dispersive properties of the tetragonal rare-earth calcium aluminates, CaLnAlO4 (Ln=Gd or Y). Sellmeier equations were derived for the spectral range of 0.35-2.1 µm. The group velocity dispersion (GVD) in CaGdAlO4 is positive at ∼1 µm, 95 fs2/mm and negative at ∼2 µm, -40 fs2/mm. The GVD values for CaYAlO4 are similar. In addition, thermo-optic coefficients, dn/dT, and thermal coefficients of the optical path were determined for CaYAlO4. dn/dT is negative at ∼1 µm, dno/dT=-7.8, and dne/dT=-8.7×10-6 K-1. Thermo-optic dispersion formulas were constructed. The obtained data are of key importance to the design of high-power mode-locked oscillators at ∼1 and ∼2 µm based on such laser hosts.

17.
Ann N Y Acad Sci ; 1397(1): 169-184, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28505395

RESUMO

The blood-brain barrier (BBB) formed by the microvascular endothelium limits cerebral drug delivery. The paraendothelial cleft is sealed by tight junctions (TJs) with a major contribution from claudin-5, which we selected as a target to modulate BBB permeability. For this purpose, drug-enhancer peptides were designed based on the first extracellular loop (ECL) of claudin-5 to allow transient BBB permeabilization. Peptidomimetics (C5C2 and derivatives, nanomolar affinity to claudin-5) size-selectively (≤40 kDa) and reversibly (12-48 h) increased the permeability of brain endothelial and claudin-5-transfected epithelial cell monolayers. Upon peptide uptake, the number of TJ strand particles diminished, claudin-5 was downregulated and redistributed from cell-cell contacts to the cytosol, and the cell shape was altered. Cellular permeability of doxorubicin (cytostatic drug, 580 Da) was enhanced after peptide administration. Mouse studies (3.5 µmol/kg i.v.) confirmed that, for both C5C2 and a d-amino acid derivative, brain uptake of Gd-diethylene-triamine penta-acetic acid (547 Da) was enhanced within 4 h of treatment. On the basis of our functional data, circular dichroism measurements, molecular modeling, and docking experiments, we suggest an association model between ß-sheets flanked by α-helices, formed by claudin-5 ECLs, and the peptides. In conclusion, we identified claudin-5 peptidomimetics that improve drug delivery through endothelial and epithelial barriers expressing claudin-5.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Claudina-5/farmacologia , Células Endoteliais/efeitos dos fármacos , Peptidomiméticos/farmacologia , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/ultraestrutura , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular , Células Cultivadas , Dicroísmo Circular , Claudina-5/química , Claudina-5/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Células Endoteliais/metabolismo , Células Endoteliais/ultraestrutura , Gadolínio DTPA/administração & dosagem , Gadolínio DTPA/farmacocinética , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia Eletrônica/métodos , Modelos Moleculares , Peptidomiméticos/química , Peptidomiméticos/farmacocinética , Permeabilidade/efeitos dos fármacos , Conformação Proteica , Ratos , Rodaminas/administração & dosagem , Rodaminas/farmacocinética , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura , Imagem com Lapso de Tempo/métodos
18.
J Am Coll Cardiol ; 69(17): 2160-2172, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28449778

RESUMO

BACKGROUND: Tachycardiomyopathy or tachycardia-induced cardiomyopathy (TCM) has been known for decades as a reversible form of nonischemic cardiomyopathy. However, its mechanism and properties remain poorly understood. OBJECTIVES: The current study investigated endomyocardial biopsy samples from patients with TCM and compared them with samples from patients with dilated cardiomyopathy (DCM) and inflammatory cardiomyopathy (ICM). METHODS: The study included 189 patients with new-onset heart failure and severely reduced ejection fraction not caused by valvular or ischemic heart disease. Nineteen patients retrospectively fulfilled common criteria of TCM, 79 patients had a diagnosis of DCM, and 91 had a diagnosis of ICM. RESULTS: Patients with TCM, on the basis of clinical criteria, had stronger myocardial expression of major histocompatibility complex class II molecule and enhanced infiltration of CD68+ macrophages compared with patients with DCM. Furthermore, when compared with patients with ICM, the presence of T cells and macrophages was significantly reduced in TCM. Myocardial fibrosis was detected to a significantly lower degree in patients with TCM compared with patients with DCM and ICM. Electron microscopic examination revealed severe structural changes in patients with TCM. A disturbed distribution pattern of mitochondria was predominantly present in TCM. Quantitative assessment of myocyte morphology revealed significantly enhanced myocyte size compared with patients with ICM. Ribonucleic acid expression analysis identified changes in metabolic pathways among the patient groups. CONCLUSIONS: TCM is characterized by changes in cardiomyocyte and mitochondrial morphology accompanied by a macrophage-dominated cardiac inflammation. Thus, further prospective studies are warranted to characterize patients with TCM by endomyocardial biopsy more clearly.


Assuntos
Cardiomiopatias/imunologia , Miocárdio/patologia , Taquicardia/complicações , Adulto , Idoso , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Feminino , Humanos , Macrófagos , Masculino , Pessoa de Meia-Idade , Mitocôndrias , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Estudos Retrospectivos , Taquicardia/metabolismo
19.
Microvasc Res ; 111: 1-11, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27988246

RESUMO

We previously demonstrated that the co-cultivation of endothelial cells with neural cells resulted in an improved integrity of the in vitro blood-brain barrier (BBB), and that this model could be useful to evaluate the transport properties of potential central nervous system disease drugs through the microvascular brain endothelial. In this study we have used real-time PCR, fluorescent microscopy, protein arrays and enzyme-linked immunosorbent assays to determine which neural- and endothelial cell-derived factors are produced in the co-culture and improve the integrity of the BBB. In addition, a further improvement of the BBB integrity was achieved by adjusting serum concentrations and growth factors or by the addition of brain pericytes. Under specific conditions expression of angiogenic, angiostatic and neurotrophic factors such as endostatin, pigment epithelium derived factor (PEDF/serpins-F1), tissue inhibitor of metalloproteinases (TIMP-1), and vascular endothelial cell growth factor (VEGF) closely mimicked the in vivo situation. Freeze-fracture analysis of these cultures demonstrated the quality and organization of the endothelial tight junction structures and their association to the two different lipidic leaflets of the membrane. Finally, a multi-cell culture model of the BBB with a transendothelial electrical resistance up to 371 (±15) Ω×cm2 was developed, which may be useful for preliminary screening of drug transport across the BBB and to evaluate cellular crosstalk of cells involved in the neurovascular unit.


Assuntos
Proteínas Angiogênicas/metabolismo , Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar , Comunicação Celular , Células Endoteliais/metabolismo , Fatores de Crescimento Neural/metabolismo , Neurônios/metabolismo , Junções Íntimas/metabolismo , Animais , Barreira Hematoencefálica/citologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Técnicas de Cocultura , Impedância Elétrica , Humanos , Acoplamento Neurovascular , Fenótipo , Transdução de Sinais , Sus scrofa , Proteínas de Junções Íntimas/metabolismo
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