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1.
J Med Genet ; 61(6): 549-552, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38272662

RESUMO

Fetal hydrops as detected by prenatal ultrasound usually carries a poor prognosis depending on the underlying aetiology. We describe the prenatal and postnatal clinical course of two unrelated female probands in whom de novo heterozygous missense variants in the planar cell polarity gene CELSR1 were detected using exome sequencing. Using several in vitro assays, we show that the CELSR1 p.(Cys1318Tyr) variant disrupted the subcellular localisation, affected cell-cell junction, impaired planar cell polarity signalling and lowered proliferation rate. These observations suggest that deleterious rare CELSR1 variants could be a possible cause of fetal hydrops.


Assuntos
Heterozigoto , Hidropisia Fetal , Mutação de Sentido Incorreto , Humanos , Feminino , Mutação de Sentido Incorreto/genética , Hidropisia Fetal/genética , Hidropisia Fetal/patologia , Gravidez , Derrame Pleural/genética , Derrame Pleural/patologia , Caderinas/genética , Sequenciamento do Exoma , Polaridade Celular/genética
2.
Genet Med ; 26(6): 101105, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38430071

RESUMO

PURPOSE: To describe a recessively inherited cerebral small vessel disease, caused by loss-of-function variants in Nitrilase1 (NIT1). METHODS: We performed exome sequencing, brain magnetic resonance imaging, neuropathology, electron microscopy, western blotting, and transcriptomic and metabolic analyses in 7 NIT1-small vessel disease patients from 5 unrelated pedigrees. RESULTS: The first identified patients were 3 siblings, compound heterozygous for the NIT1 c.727C>T; (p.Arg243Trp) variant and the NIT1 c.198_199del; p.(Ala68∗) variant. The 4 additional patients were single cases from 4 unrelated pedigrees and were all homozygous for the NIT1 c.727C>T; p.(Arg243Trp) variant. Patients presented in mid-adulthood with movement disorders. All patients had striking abnormalities on brain magnetic resonance imaging, with numerous and massively dilated basal ganglia perivascular spaces. Three patients had non-lobar intracerebral hemorrhage between age 45 and 60, which was fatal in 2 cases. Western blotting on patient fibroblasts showed absence of NIT1 protein, and metabolic analysis in urine confirmed loss of NIT1 enzymatic function. Brain autopsy revealed large electron-dense deposits in the vessel walls of small and medium sized cerebral arteries. CONCLUSION: NIT1-small vessel disease is a novel, autosomal recessively inherited cerebral small vessel disease characterized by a triad of movement disorders, massively dilated basal ganglia perivascular spaces, and intracerebral hemorrhage.


Assuntos
Hemorragia Cerebral , Doenças de Pequenos Vasos Cerebrais , Transtornos dos Movimentos , Linhagem , Humanos , Feminino , Masculino , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/patologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Pessoa de Meia-Idade , Hemorragia Cerebral/genética , Hemorragia Cerebral/patologia , Hemorragia Cerebral/diagnóstico por imagem , Transtornos dos Movimentos/genética , Transtornos dos Movimentos/patologia , Transtornos dos Movimentos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Alelos , Adulto , Idoso , Sistema Glinfático/patologia , Sistema Glinfático/diagnóstico por imagem , Sequenciamento do Exoma , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Aminoidrolases/genética
3.
Hum Mol Genet ; 29(11): 1853-1863, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-31960911

RESUMO

CADASIL is a vascular protein aggregation disorder caused by cysteine-altering NOTCH3 variants, leading to mid-adult-onset stroke and dementia. Here, we report individuals with a cysteine-altering NOTCH3 variant that induces exon 9 skipping, mimicking therapeutic NOTCH3 cysteine correction. The index came to our attention after a coincidental finding on a commercial screening MRI, revealing white matter hyperintensities. A heterozygous NOTCH3 c.1492G>T, p.Gly498Cys variant, was identified using a gene panel, which was also present in four first- and second-degree relatives. Although some degree of white matter hyperintensities was present on MRI in all family members with the NOTCH3 variant, the CADASIL phenotype was mild, as none had lacunes on MRI and there was no disability or cognitive impairment above the age of 60 years. RT-PCR and Sanger sequencing analysis on patient fibroblast RNA revealed that exon 9 was absent from the majority of NOTCH3 transcripts of the mutant allele, effectively excluding the mutation. NOTCH3 aggregation was assessed in skin biopsies using electron microscopy and immunohistochemistry and did not show granular osmiophilic material and only very mild NOTCH3 staining. For purposes of therapeutic translatability, we show that, in cell models, exon 9 exclusion can be obtained using antisense-mediated exon skipping and CRISPR/Cas9-mediated genome editing. In conclusion, this study provides the first in-human evidence that cysteine corrective NOTCH3 exon skipping is associated with less NOTCH3 aggregation and an attenuated phenotype, justifying further therapeutic development of NOTCH3 cysteine correction for CADASIL.


Assuntos
CADASIL/genética , Cisteína/genética , Agregação Patológica de Proteínas/genética , Receptor Notch3/genética , Substância Branca/metabolismo , Adulto , Idoso , Biópsia , CADASIL/diagnóstico por imagem , CADASIL/metabolismo , CADASIL/fisiopatologia , Sistemas CRISPR-Cas/genética , Éxons/genética , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Agregação Patológica de Proteínas/diagnóstico por imagem , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/patologia , Índice de Gravidade de Doença , Pele/química , Pele/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
4.
Magn Reson Med ; 87(3): 1276-1288, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34655092

RESUMO

PURPOSE: To employ an off-resonance saturation method to measure the mineral-iron pool in the postmortem brain, which is an endogenous contrast agent that can give information on cellular iron status. METHODS: An off-resonance saturation acquisition protocol was implemented on a 7 Tesla preclinical scanner, and the contrast maps were fitted to an established analytical model. The method was validated by correlation and Bland-Altman analysis on a ferritin-containing phantom. Mineral-iron maps were obtained from postmortem tissue of patients with neurological diseases characterized by brain iron accumulation, that is, Alzheimer disease, Huntington disease, and aceruloplasminemia, and validated with histology. Transverse relaxation rate and magnetic susceptibility values were used for comparison. RESULTS: In postmortem tissue, the mineral-iron contrast colocalizes with histological iron staining in all the cases. Iron concentrations obtained via the off-resonance saturation method are in agreement with literature. CONCLUSIONS: Off-resonance saturation is an effective way to detect iron in gray matter structures and partially mitigate for the presence of myelin. If a reference region with little iron is available in the tissue, the method can produce quantitative iron maps. This method is applicable in the study of diseases characterized by brain iron accumulation and can complement existing iron-sensitive parametric methods.


Assuntos
Distúrbios do Metabolismo do Ferro , Ferro , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Minerais
5.
Ophthalmology ; 129(4): 421-430, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34780841

RESUMO

PURPOSE: Individuals with gray, blue, or green eyes have a higher chance of developing uveal melanoma (UM) than those with brown eyes. We wondered whether iris pigmentation might be related not only to predisposition to UM but also to its behavior; therefore, we compared the clinical, histopathologic, and genetic characteristics of UM between eyes with different colors. DESIGN: We determined iris color in a large cohort of patients enucleated for UM. Clinical and histopathologic tumor characteristics, chromosome status, and survival were compared among 3 groups on the basis of iris color. PARTICIPANTS: A total of 412 patients with choroidal/ciliary body UM, who had undergone primary enucleation at the Leiden University Medical Center, Leiden, The Netherlands, between 1993 and 2019, were divided into 3 groups based on iris color: gray/blue, green/hazel, and brown. The validation cohort included 934 patients with choroidal/ciliary body UM treated at Wills Eye Hospital (WEH). METHODS: Comparison of clinical, histopathologic, and genetic characteristics of UM in patients with different iris colors. MAIN OUTCOME MEASURES: Melanoma-related survival in UM patients, divided over 3 iris color groups, in relation to the tumor's chromosome 3 and 8q status. RESULTS: Moderate and heavy tumor pigmentations were especially seen in eyes with a brown iris (P < 0.001). Survival did not differ between patients with different iris colors (P = 0.27); however, in patients with a light iris, copy number changes in chromosome 3 and 8q had a greater influence on survival than in patients with a dark iris. Likewise, chromosome 3 and chromosome 8q status affected survival more among patients with lightly pigmented tumors than in patients with heavily pigmented tumors. The WEH cohort similarly showed a greater influence of chromosome aberrations in light-eyed individuals. CONCLUSIONS: Although iris color by itself did not relate to UM-related survival, chromosome 3 and 8q aberrations had a larger influence on survival in patients with a light iris than those with a brown iris. This suggests a synergistic effect of iris pigmentation and chromosome status in the regulation of oncogenic behavior of UM. Iris color should be taken into consideration when calculating a patient's risk for developing metastases.


Assuntos
Melanoma , Neoplasias Uveais , Aberrações Cromossômicas , Cromossomos Humanos Par 3/genética , Cor de Olho/genética , Humanos , Iris/patologia , Melanoma/patologia , Prognóstico , Neoplasias Uveais/patologia
6.
BMC Neurol ; 21(1): 379, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587899

RESUMO

BACKGROUND: Evidence indicates that inflammatory processes are involved in radicular pain as well as in resorption of herniated disc tissue. Furthermore there are indications that the presence of vertebral end plate pathology (Modic changes; MC) is associated with a negative effect on inflammation. It is hypothesized that in patients with MC, the (possibly bacterial induced) inflammation will be accompanied by pro inflammatory cytokines that worsen the outcome, and that in patients without MC, the inflammation is accompanied by cytokines that induce a resorption process to accelerate recovery. METHODS: This prospective cohort study will include 160 lumbar and 160 cervical patients (total of 320), which are scheduled for surgery for either a lumbar or cervical herniated disc with ages between 18 and 75. The main and interaction effects of local bacterial infection (culture), inflammatory cells in disc material (immunohistology), MC (MRI), and blood biomarkers indicating inflammation or infection (blood sample evaluation) will be evaluated. Clinical parameters to be evaluated are leg pain on the 11 point NRS pain scale, Oswestry (lumbar spine) or Neck (cervical spine) Disability Index, Global Perceived Recovery, Womac Questionnaire, and medication status, at baseline, and after 6, 16, 26 and 52 weeks. DISCUSSION: Gaining insight in the aetiology of pain and discomfort in radiculopathy caused by a herniated disc could lead to more effective management of patients. If the type of inflammatory cells shows to be of major influence on the rate of recovery, new immunomodulating treatment strategies can be developed to decrease the duration and intensity of symptoms. Moreover, identifying a beneficial inflammatory response in the disc through a biomarker in blood could lead to early identification of patients whose herniations will resorb spontaneously versus those that require surgery. TRIAL REGISTRATION: prospectively enrolled at trialregister.nl, ID: NL8464 .


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Radiculopatia , Adolescente , Adulto , Idoso , Humanos , Inflamação , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
7.
Proc Natl Acad Sci U S A ; 115(4): E782-E791, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29311311

RESUMO

Point mutations in the amyloid-ß (Aß) coding region produce a combination of mutant and WT Aß isoforms that yield unique clinicopathologies in familial Alzheimer's disease (fAD) and cerebral amyloid angiopathy (fCAA) patients. Here, we report a method to investigate the structural variability of amyloid deposits found in fAD, fCAA, and sporadic AD (sAD). Using this approach, we demonstrate that mutant Aß determines WT Aß conformation through prion template-directed misfolding. Using principal component analysis of multiple structure-sensitive fluorescent amyloid-binding dyes, we assessed the conformational variability of Aß deposits in fAD, fCAA, and sAD patients. Comparing many deposits from a given patient with the overall population, we found that intrapatient variability is much lower than interpatient variability for both disease types. In a given brain, we observed one or two structurally distinct forms. When two forms coexist, they segregate between the parenchyma and cerebrovasculature, particularly in fAD patients. Compared with sAD samples, deposits from fAD patients show less intersubject variability, and little overlap exists between fAD and sAD deposits. Finally, we examined whether E22G (Arctic) or E22Q (Dutch) mutants direct the misfolding of WT Aß, leading to fAD-like plaques in vivo. Intracerebrally injecting mutant Aß40 fibrils into transgenic mice expressing only WT Aß induced the deposition of plaques with many biochemical hallmarks of fAD. Thus, mutant Aß40 prions induce a conformation of WT Aß similar to that found in fAD deposits. These findings indicate that diverse AD phenotypes likely arise from one or more initial Aß prion conformations, which kinetically dominate the spread of prions in the brain.


Assuntos
Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides/metabolismo , Conformação Proteica , Dobramento de Proteína , Peptídeos beta-Amiloides/genética , Animais , Camundongos Transgênicos , Mutação Puntual
8.
Eur Spine J ; 29(3): 646, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31893304

RESUMO

In Tables 3 and 4: In the first column and row, the text reads "Mixed model test (patients with Modic changes)". This should have been just "Mixed model". The complete correct Tables 3 and 4 are given below.

9.
Eur Spine J ; 28(11): 2579-2587, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31440895

RESUMO

PURPOSE: To study the interaction between Modic changes (MC) and inflammation by macrophages in the disc, in relation to clinical symptoms before and after discectomy for lumbar disc herniation. METHODS: Disc tissue was embedded in paraffin and stained with haematoxylin and CD68. Subsequently, tissue samples were categorized for degree of inflammation. Type of MC was scored on MRI at baseline. Roland Disability Questionnaire (RDQ) score and visual analogue scale for back pain and leg pain separately were considered at baseline and 1-year follow-up post-surgery. Main and interaction effects of MC and inflammation were tested against clinical outcome questionnaires. In addition, this analysis was repeated in bulging and extruded discs separately. RESULTS: Disc material and MRI's of 119 patients were retrieved and analysed. Forty-eight patients demonstrated mild inflammation, 45 showed moderate inflammation, and 26 showed considerable inflammation. In total, 49 out of 119 patients demonstrated MC. Grade of disc inflammation did not associate with the presence of MC. At baseline, no main or interaction effects of MC and inflammation were found on the clinical scores. However, during follow-up after discectomy, significant interaction effects were found for RDQ score: Only in patients with MC at baseline, patients remained significantly more disabled (3.2 points p = 0.006) if they showed considerable disc inflammation compared to patients with mild inflammation. The additional analysis showed similar results in extruded discs, but no significant effects in bulging discs. CONCLUSIONS: An interaction effect of MC and disc inflammation by macrophages is present. Only in patients with MC, those with considerable inflammation recover less satisfactory during follow-up after surgery. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Inflamação/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Disco Intervertebral/metabolismo , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Macrófagos/metabolismo , Adulto , Avaliação da Deficiência , Discotomia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Escala Visual Analógica
10.
Acta Neurochir (Wien) ; 161(2): 263-269, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30560377

RESUMO

BACKGROUND: In patients with persistent symptoms of meralgia paresthetica, a neurectomy of the lateral femoral cutaneous nerve (LFCN) can be performed to alleviate pain symptoms. The neurectomy procedure can be performed either as a primary procedure or after failure of a previously performed neurolysis or decompression of the LFNC (secondary neurectomy). The goal of the present study was to quantify the histopathologic changes inside the LFCN obtained from patients with persistent symptoms of meralgia paresthetica, and specifically to compare to what extend these changes are present after primary versus secondary neurectomy. METHODS: A total of 39 consecutive cases were analyzed microscopically: in 29 cases, the neurectomy had been performed as primary procedure, in 10 cases, after failed neurolysis. Intraneural changes were quantified for the (1) thickening of perineurium, (2) deposition of mucoid, and (3) percentage of collagen. Analysis was performed at three levels: proximal to, at, and distal to the previous site of compression. In addition, correlations were investigated for the duration of symptoms and the body mass index (BMI) of the patient. RESULTS: Intraneural changes were found consistently in all cases. There was no significant difference for the primary and secondary neurectomy groups. There was also no relation with the previous site of compression. There was a weak correlation between the occurrence of intraneural changes and the duration of symptoms, although this difference was not statistically significant. CONCLUSIONS: Histopathological changes in this study were found in all patients with persistent symptoms of meralgia paresthetica regardless of a previously performed neurolysis procedure. This finding suggests that the intraneural changes that occur in persistent meralgia paresthetica are largely irreversible and support the surgical strategy of neurectomy as an alternative to neurolysis, also for primary surgical treatment and not only after failure of neurolysis.


Assuntos
Nervo Femoral/patologia , Neuropatia Femoral/patologia , Adulto , Colágeno/metabolismo , Descompressão Cirúrgica , Feminino , Nervo Femoral/metabolismo , Nervo Femoral/cirurgia , Neuropatia Femoral/metabolismo , Neuropatia Femoral/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Muco/metabolismo
11.
Stroke ; 49(9): 2081-2087, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30354978

RESUMO

Background and Purpose- Previous studies of symptomatic and asymptomatic hereditary cerebral amyloid angiopathy (CAA) patients offered the possibility to study the radiological manifestations of CAA in the early stages of the disease. Recently, a striped cortex, observable as hypointense lines perpendicular to the pial surface on T2*-weighted 7T magnetic resonance imaging (MRI), was detected in 40% of the symptomatic hereditary CAA patients. However, the origin of these MRI contrast changes is unknown. This study aimed at defining the underlying pathology associated with the in vivo observed striped pattern. Methods- Formalin-fixed postmortem brain material including the occipital lobe of 4 hereditary cerebral hemorrhage with amyloidosis-Dutch type (HCHWA-D) cases and 6 sporadic CAA cases were selected from local neuropathology tissue collections. Depending on the availability of the material, intact hemispheres or brain slabs including the occipital lobe of these patients were screened for the presence of a striped cortex. Regions containing the striped cortex were then subjected to high-resolution 7T MRI and histopathologic examination. Results- We found 2 hereditary cerebral hemorrhage with amyloidosis-Dutch type cases and 1 sporadic CAA case with striped patterns in the occipital cortex resembling the in vivo signal. Histopathologic examination showed that the striped pattern in the cortex at 7T MRI is because of iron accumulation and calcification of penetrating arteries. The presence of both nonheme iron and calcification on penetrating arteries causes signal loss and hence the abnormal striped patterns in the cortical ribbon on T2*-weighted MRI. Conclusions- We identified iron accumulation and calcification of the vessel wall in hereditary cerebral hemorrhage with amyloidosis-Dutch type as the histopathologic correlates of the striped cortex observed on in vivo 7T MRI.


Assuntos
Angiopatia Amiloide Cerebral Familiar/diagnóstico por imagem , Ferro/metabolismo , Lobo Occipital/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Angiopatia Amiloide Cerebral/metabolismo , Angiopatia Amiloide Cerebral/patologia , Angiopatia Amiloide Cerebral Familiar/metabolismo , Angiopatia Amiloide Cerebral Familiar/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Occipital/metabolismo , Lobo Occipital/patologia , Calcificação Vascular/patologia
13.
Rheumatology (Oxford) ; 56(1): 77-86, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28028157

RESUMO

OBJECTIVES: Neuropsychiatric (NP) involvement is a poorly understood manifestation of SLE. We studied post-mortem histopathology in relation to clinical NPSLE syndromes and complement deposition in brains of NPSLE and SLE patients and controls. Furthermore, we investigated the correlation between cerebral post-mortem histopathology and ex vivo 7 T MRI findings in SLE and NPSLE. METHODS: A nationwide search for autopsy material yielded brain tissue from 16 NPSLE and 18 SLE patients. Brains obtained from 24 patients who died of acute cardiac events served as controls. Apart from a histopathological evaluation, paraffin-embedded cortical tissue was stained for components of the classical, lectin and terminal complement pathways. RESULTS: Diffuse vasculopathy, microinfarction, macroinfarction, vasculitis and microthrombi occurred significantly more often in NPSLE than SLE patients and were absent in controls. Focal vasculopathy was found in both SLE patients and controls. Complement deposition was strongly associated with both SLE and NPSLE, but not with controls (P < 0.001). Microthrombi were found uniquely in NPSLE and were associated with C4d and C5b-9 deposits (P < 0.05). A 7 T MRI was unable to detect most small vessel injury that was visible histopathologically. CONCLUSION: Our study demonstrates that histopathological lesions in NPSLE represent a continuum, ranging from non-specific lesions such as focal vasculopathy, to more specific lesions including C4d- and C5b-9-associated microthrombi and diffuse vasculopathy related to clinical syndromes defining NPSLE. Complement deposition may be a key factor in the interaction between circulating autoantibodies and thromboischaemic lesions observed in NPSLE. Therefore, complement inhibition may have novel therapeutic potential in NPSLE.


Assuntos
Infarto Encefálico/patologia , Encéfalo/patologia , Trombose Intracraniana/patologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/patologia , Vasculite do Sistema Nervoso Central/patologia , Adulto , Idoso , Autoanticorpos/imunologia , Autopsia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/etiologia , Infarto Encefálico/metabolismo , Estudos de Casos e Controles , Complemento C4b/imunologia , Complemento C4b/metabolismo , Complemento C5b/imunologia , Complemento C5b/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Via Clássica do Complemento , Lectina de Ligação a Manose da Via do Complemento , Proteínas do Sistema Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/etiologia , Trombose Intracraniana/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/complicações , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Vasculite Associada ao Lúpus do Sistema Nervoso Central/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/etiologia , Vasculite do Sistema Nervoso Central/metabolismo
14.
Mod Pathol ; 29(6): 582-90, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26990975

RESUMO

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas that can show overlapping features with benign neurofibromas as well as high-grade sarcomas. Additional diagnostic markers are needed to aid in this often challenging differential diagnosis. Recently mutations in two critical components of the polycomb repressor 2 (PRC2) complex, SUZ12 and EED, were reported to occur specifically in MPNSTs while such mutations are absent in neurofibromas, both in the setting of neurofibromatosis (NF) and sporadic cases. Furthermore, both SUZ12 and EED mutations in MPNSTs were associated with loss of H3K27 tri-methylation, a downstream target of PRC2. Therefore, we tested whether H3K27me3 immunohistochemistry is useful as a diagnostic and prognostic marker for MPNSTs. We performed H3K27me3 immunohistochemistry in 162 primary MPNSTs, 97 neurofibromas and 341 other tumors using tissue microarray. We observed loss of H3K27me3 in 34% (55/162) of all MPNSTs while expression was retained in all neurofibromas including atypical (n=8) and plexiform subtypes (n=24). Within other tumors we detected loss of H3K27me3 in only 7% (24/341). Surprisingly, 60% (9/15) of synovial sarcomas and 38% (3/8) of fibrosarcomatous dermatofibrosarcoma protuberans (DFSP) showed loss of H3K27 trimethylation. Only 1 out of 44 schwannomas showed loss of H3K27me3 and all 4 perineuriomas showed intact H3K27me3. Furthermore, MPNSTs with loss of H3K27 tri-methylation showed inferior survival compared with MPNSTs with intact H3K27 tri-methylation, which was validated in two independent cohorts. Our results indicate that H3K27me3 immunohistochemistry is useful as a diagnostic marker, in which loss of H3K27me3 favors MPNST above neurofibroma. However, H3K27me3 immunohistochemistry is not suitable to distinguish MPNST from its morphological mimicker synovial sarcoma or fibrosarcomatous DFSP. Since loss of H3K27 tri-methylation was related to poorer survival in MPNST, chromatin modification mediated by this specific histone seems to orchestrate more aggressive tumour biology.


Assuntos
Metilação de DNA , Histonas/análise , Imuno-Histoquímica , Neurilemoma/química , Adolescente , Adulto , Idoso , California , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Estimativa de Kaplan-Meier , Lisina , Masculino , Pessoa de Meia-Idade , Países Baixos , Neurilemoma/genética , Neurilemoma/mortalidade , Neurilemoma/patologia , Valor Preditivo dos Testes , Prognóstico , Texas , Fatores de Tempo , Análise Serial de Tecidos , Adulto Jovem
15.
Mol Hum Reprod ; 21(11): 857-64, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26307194

RESUMO

Microchimerism is the occurrence of small populations of cells with a different genetic background within an individual. Tissue microchimerism is considered to be primarily pregnancy-derived and is often studied relative to female-dominant autoimmune diseases, pregnancy complications, malignancies, response to injury, and transplantation outcomes. A particular distribution pattern of chimeric cells across various organs was recently described in a model of murine pregnancies. Our aim was to determine the frequency and distribution of tissue microchimerism across organs during and after pregnancy in humans. We performed in situ hybridization of the Y chromosome on paraffin-embedded autopsy samples of kidneys, livers, spleens, lungs, hearts and brains that were collected from 26 women who died while pregnant or within 1 month after delivery of a son. Frequencies of chimeric cells in various tissues were compared with those of a control group of non-pregnant women who had delivered sons. Tissue microchimerism occurred significantly more frequently in the lungs, spleens, livers, kidneys and hearts of pregnant women compared with non-pregnant women (all P < 0.01). We showed that some of the chimeric cells were CD3+ or CD34+. After correction for cell density, the lung was most chimeric (470 Y chromosome-positive nuclei per million nuclei scored), followed by the spleen (208 Y+/10(6) nuclei), liver (192 Y+/10(6) nuclei), kidney (135 Y+/10(6) nuclei), brain (85 Y+/10(6) nuclei) and heart (40 Y+/10(6) nuclei). Data from this unique study group of women who died while pregnant or shortly after delivery provide information about the number and physiologic distribution of chimeric cells in organs of pregnant women. We demonstrate that during pregnancy, a boost of chimeric cells is observed in women, with a distribution across organs, that parallels findings in mouse models.


Assuntos
Autopsia , Quimerismo , Cromossomos Humanos Y/genética , Adolescente , Adulto , Antígenos CD34/metabolismo , Encéfalo/metabolismo , Complexo CD3/metabolismo , Feminino , Humanos , Hibridização In Situ , Técnicas In Vitro , Fígado/metabolismo , Pulmão/metabolismo , Pessoa de Meia-Idade , Gravidez , Baço/metabolismo , Adulto Jovem
16.
Brain ; 137(Pt 5): 1361-73, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24722252

RESUMO

Pathological accumulation of intermediate filaments can be observed in neurodegenerative disorders, such as Alzheimer's disease, frontotemporal dementia and Parkinson's disease, and is also characteristic of neuronal intermediate filament inclusion disease. Intermediate filaments type IV include three neurofilament proteins (light, medium and heavy molecular weight neurofilament subunits) and α-internexin. The phosphorylation of intermediate filament proteins contributes to axonal growth, and is regulated by protein kinase A. Here we describe a family with a novel late-onset neurodegenerative disorder presenting with dementia and/or parkinsonism in 12 affected individuals. The disorder is characterized by a unique neuropathological phenotype displaying abundant neuronal inclusions by haematoxylin and eosin staining throughout the brain with immunoreactivity for intermediate filaments. Combining linkage analysis, exome sequencing and proteomics analysis, we identified a heterozygous c.149T>G (p.Leu50Arg) missense mutation in the gene encoding the protein kinase A type I-beta regulatory subunit (PRKAR1B). The pathogenicity of the mutation is supported by segregation in the family, absence in variant databases, and the specific accumulation of PRKAR1B in the inclusions in our cases associated with a specific biochemical pattern of PRKAR1B. Screening of PRKAR1B in 138 patients with Parkinson's disease and 56 patients with frontotemporal dementia did not identify additional novel pathogenic mutations. Our findings link a pathogenic PRKAR1B mutation to a novel hereditary neurodegenerative disorder and suggest an altered protein kinase A function through a reduced binding of the regulatory subunit to the A-kinase anchoring protein and the catalytic subunit of protein kinase A, which might result in subcellular dislocalization of the catalytic subunit and hyperphosphorylation of intermediate filaments.


Assuntos
Subunidade RIbeta da Proteína Quinase Dependente de AMP Cíclico/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Polimorfismo de Nucleotídeo Único/genética , Idoso , Peptídeos beta-Amiloides/metabolismo , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/química , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Tomografia com Microscopia Eletrônica , Saúde da Família , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Lobo Frontal/ultraestrutura , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Proteínas do Tecido Nervoso/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo
17.
Rev Neurosci ; 25(5): 641-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24870607

RESUMO

Hereditary cerebral hemorrhage with amyloidosis - Dutch type is an autosomal dominant hereditary disease caused by a point mutation in the amyloid precursor protein gene on chromosome 21. The mutation causes an amino acid substitution at codon 693 (E22Q), the 'Dutch mutation'. Amyloid ß, the product after cleavage of the amyloid precursor protein, is secreted into the extracellular space. The Dutch mutation leads to altered amyloid ß cleavage and secretion, enhanced aggregation properties, higher proteolysis resistance, lowered brain efflux transporter affinity, and enhanced cell surfaces binding. All these result in amyloid ß accumulation in cerebral vessel walls, causing cell death and vessel wall integrity loss, making cerebral vessel walls in hereditary cerebral hemorrhage with amyloidosis-Dutch type more prone to rupture and obstruction, leading to hemorrhages and infarcts. Studying the effects of altered amyloid ß metabolism due to mutations like the 'Dutch' provides us with a better understanding of amyloid ß toxicity, also in other amyloid ß diseases like sporadic cerebral amyloid angiopathy and Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Angiopatia Amiloide Cerebral Familiar/metabolismo , Placa Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Angiopatia Amiloide Cerebral Familiar/genética , Angiopatia Amiloide Cerebral Familiar/patologia , Humanos , Mutação , Placa Amiloide/genética , Placa Amiloide/patologia , Proteólise
18.
Hum Mutat ; 34(11): 1486-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24000151

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by stereotyped missense mutations in NOTCH3. Whether these mutations lead to the CADASIL phenotype via a neomorphic effect, or rather by a hypomorphic effect, is subject of debate. Here, we report two novel NOTCH3 mutations, both leading to a premature stop codon with predicted loss of NOTCH3 function. The first mutation, c.307C>T, p.Arg103*, was detected in two brothers aged 50 and 55 years, with a brain MRI and skin biopsy incompatible with CADASIL. The other mutation was found in a 40-year-old CADASIL patient compound heterozygous for a pathogenic NOTCH3 mutation (c.2129A>G, p.Tyr710Cys) and an intragenic frameshift deletion. The deletion was inherited from his father, who did not have the skin biopsy abnormalities seen in CADASIL patients. These individuals with rare NOTCH3 mutations indicate that hypomorphic NOTCH3 alleles do not cause CADASIL.


Assuntos
Alelos , CADASIL/diagnóstico , CADASIL/genética , Fenótipo , Receptores Notch/genética , Adulto , Encéfalo/patologia , Análise Mutacional de DNA , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Receptor Notch3 , Deleção de Sequência
19.
Ophthalmol Sci ; 3(3): 100297, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37193315

RESUMO

Purpose: Heavy pigmentation is known to be a prognostic risk factor in uveal melanoma (UM). We analyzed whether genetic tumor parameters were associated with tumor pigmentation and whether pigmentation should be included in prognostic tests. Design: Retrospective comparison of clinical, histopathological, and genetic features and survival in UM with different pigmentation. Participants: A total of 1058 patients with UM from a White European population with diverse eye colors enucleated between 1972 and 2021. Methods: Cox regression and log-rank tests were used for survival analysis; the chi-square test and Mann-Whitney U test were used for correlation analysis. Main Outcome Measures: Uveal melanoma-related survival based on tumor pigmentation and chromosome status, correlation of tumor pigmentation with prognostic factors. Results: The 5-year UM-related mortality was 8% in patients with nonpigmented tumors (n = 54), 25% with lightly pigmented tumors (n = 489), 41% with moderately pigmented tumors (n = 333), and 33% with dark tumors (n = 178) (P < 0.001). The percentage of tumors with monosomy 3 (M3) or 8q gain increased with increasing pigmentation (31%, 46%, 62%, and 70% having M3 [P < 0.001], and 19%, 43%, 61%, and 63% having 8q gain [P < 0.001] in the 4 increasing pigment groups, respectively). BRCA-associated protein 1 (BAP1) loss (known for 204 cases) was associated with increased tumor pigmentation (P = 0.001). Cox regression analysis on survival showed that when chromosome status and pigmentation were both included, pigmentation was not an independent prognostic indicator. Preferentially expressed antigen in melanoma (PRAME) expression was a significant prognostic marker in light tumors (P = 0.02) but not in dark tumors (P = 0.85). Conclusions: Patients with moderately and heavily pigmented tumors showed a significantly higher UM-related mortality than patients with unpigmented and light tumors (P < 0.001), supporting prior reports on the relation between increased tumor pigmentation and a worse prognosis. Although we previously showed that a dark eye color was associated with tumor pigmentation, we now show that the tumor's genetic status (chromosome 3 and 8q/BAP1 status) is also related to tumor pigmentation. When pigmentation and chromosome 3 status are both included in a Cox regression analysis, pigmentation is not an independent prognostic factor. However, evidence from this and previous studies shows that chromosome changes and PRAME expression have a stronger association with survival when they occur in light tumors than in dark ones. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.

20.
Thromb Res ; 221: 10-18, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36435047

RESUMO

BACKGROUND AND OBJECTIVES: Patients with glioblastoma have a high risk of developing venous thromboembolism (VTE). However, the role of underlying genetic risk factors remains largely unknown. Therefore, the aim of this study was to discover whether genetic aberrations in glioblastoma associate with VTE risk. METHODS: In this cohort study, all consecutive patients diagnosed with glioblastoma in two Dutch hospitals between February 2017 and August 2020 were included. Targeted DNA next-generation sequencing of all glioblastomas was performed for diagnostic purposes and included mutational status of the genes ATRX, BRAF, CIC, FUBP1, H3F3A, IDH1, IDH2, PIK3CA, PTEN and TP53 and amplification/gain or deletion of BRAF, CDKN2A, EGFR, NOTCH1 and PTEN. The primary outcome was VTE within three months before glioblastoma diagnosis until two years after. Cumulative incidences were determined using competing risk analysis adjusting for mortality. Univariable Cox regression analysis was performed to determine hazard ratios. RESULTS: From 324 patients with glioblastoma, 25 were diagnosed with VTE. Patients with a CDKN2A deletion had a 12-month adjusted cumulative incidence of VTE of 12.5 % (95%CI: 7.3-19.3) compared with 5.4 % (95%CI: 2.6-9.6) in patients with CDKN2A wildtype (p = 0.020), corresponding to a HR of 2.53 (95%CI: 1.12-5.73, p = 0.026). No significant associations were found between any of the other investigated genes and VTE. CONCLUSION: This study suggests a potential role for CDKN2A deletion in glioblastoma-related VTE. Therefore, once independently validated, CDKN2A mutational status may be a promising predictor to identify glioblastoma patients at high risk for VTE, who may benefit from thromboprophylaxis.


Assuntos
Glioblastoma , Tromboembolia Venosa , Humanos , Glioblastoma/complicações , Glioblastoma/genética , Estudos de Coortes , Tromboembolia Venosa/tratamento farmacológico , Anticoagulantes/uso terapêutico , Proteínas Proto-Oncogênicas B-raf , Fatores de Risco , Proteínas de Ligação a DNA , Proteínas de Ligação a RNA
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