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1.
J Biophotonics ; 17(1): e202300079, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37725434

RESUMO

During thyroid surgery fast and reliable intra-operative pathological feedback has the potential to avoid a two-stage procedure and significantly reduce health care costs in patients undergoing a diagnostic hemithyroidectomy (HT). We explored higher harmonic generation (HHG) microscopy, which combines second harmonic generation (SHG), third harmonic generation (THG), and multiphoton excited autofluorescence (MPEF) for this purpose. With a compact, portable HHG microscope, images of freshly excised healthy tissue, benign nodules (follicular adenoma) and malignant tissue (papillary carcinoma, follicular carcinoma and spindle cell carcinoma) were recorded. The images were generated on unprocessed tissue within minutes and show relevant morphological thyroid structures in good accordance with the histology images. The thyroid follicle architecture, cells, cell nuclei (THG), collagen organization (SHG) and the distribution of thyroglobulin and/or thyroid hormones T3 or T4 (MPEF) could be visualized. We conclude that SHG/THG/MPEF imaging is a promising tool for clinical intraoperative assessment of thyroid tissue.


Assuntos
Microscopia , Glândula Tireoide , Humanos , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Colágeno , Microscopia de Fluorescência por Excitação Multifotônica/métodos
3.
Clin Radiol ; 76(11): 838-845, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34404517

RESUMO

AIM: To evaluate a deep-learning-based computer-aided detection (DL-CAD) software system for pulmonary nodule detection on computed tomography (CT) images and assess its added value in the clinical practice of a large teaching hospital. MATERIALS AND METHODS: A retrospective analysis was performed of 145 chest CT examinations by comparing the output of the DL-CAD software with a reference standard based on the consensus reading of three radiologists. For every nodule in each scan, the location, composition, and maximum diameter in the axial plane were recorded. The subgroup of chest CT examinations (n = 97) without any nodules was used to determine the negative predictive value at the given clinical sensitivity threshold setting. RESULTS: The radiologists found 91 nodules and the CAD system 130 nodules of which 80 were true positive. The measured sensitivity was 88% and the mean false-positive rate was 1.04 false positives/scan. The negative predictive value was 95%. For 23 nodules, there was a size discrepancy of which 19 (83%) were measured smaller by the radiologist. The agreement of nodule composition between the CAD results and the reference standard was 95%. CONCLUSIONS: The present study found a sensitivity of 88% and a false-positive rate of 1.04 false positives/scan, which match the vendor specification. Together with the measured negative predictive value of 95% the system performs very well; however, these rates are still not good enough to replace the radiologist, even for the specific task of nodule detection. Furthermore, a surprisingly high rate of overestimation of nodule size was observed, which can lead to too many follow-up examinations.


Assuntos
Aprendizado Profundo , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitais de Ensino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
5.
Endocr Relat Cancer ; 23(9): 727-37, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27535174

RESUMO

Adrenocortical carcinoma (ACC) is a rare malignancy with a poor prognosis. Discrimination of ACCs from adrenocortical adenomas (ACAs) is challenging on both imaging and histopathological grounds. High IGF2 expression is associated with malignancy, but shows large variability. In this study, we investigate whether specific methylation patterns of IGF2 regulatory regions could serve as a valuable biomarker in distinguishing ACCs from ACAs. Pyrosequencing was used to analyse methylation percentages in DMR0, DMR2, imprinting control region (ICR) (consisting of CTCF3 and CTCF6) and the H19 promoter. Expression of IGF2 and H19 mRNA was assessed by real-time quantitative PCR. Analyses were performed in 24 ACCs, 14 ACAs and 11 normal adrenals. Using receiver operating characteristic (ROC) analysis, we evaluated which regions showed the best predictive value for diagnosis of ACC and determined the diagnostic accuracy of these regions. In ACCs, the DMR0, CTCF3, CTCF6 and the H19 promoter were positively correlated with IGF2 mRNA expression (P<0.05). Methylation in the most discriminating regions distinguished ACCs from ACAs with a sensitivity of 96%, specificity of 100% and an area under the curve (AUC) of 0.997±0.005. Our findings were validated in an independent cohort of 9 ACCs and 13 ACAs, resulting in a sensitivity of 89% and a specificity of 92%. Thus, methylation patterns of IGF2 regulatory regions can discriminate ACCs from ACAs with high diagnostic accuracy. This proposed test may become the first objective diagnostic tool to assess malignancy in adrenal tumours and facilitate the choice of therapeutic strategies in this group of patients.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Adenoma Adrenocortical/genética , Carcinoma Adrenocortical/genética , Fator de Crescimento Insulin-Like II/genética , Adolescente , Neoplasias do Córtex Suprarrenal/diagnóstico , Adenoma Adrenocortical/diagnóstico , Carcinoma Adrenocortical/diagnóstico , Adulto , Idoso , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Criança , Metilação de DNA , Decitabina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Sequências Reguladoras de Ácido Nucleico , Adulto Jovem
6.
AJNR Am J Neuroradiol ; 36(2): 355-60, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25523593

RESUMO

BACKGROUND AND PURPOSE: Intratumoral calcifications are very important in the diagnosis of retinoblastoma. Although CT is considered superior in detecting calcification, its ionizing radiation, especially in patients with hereditary retinoblastoma, should be avoided. The purpose of our study was to validate T2*WI for the detection of calcification in retinoblastoma with ex vivo CT as the criterion standard. MATERIALS AND METHODS: Twenty-two consecutive patients with retinoblastoma (mean age, 21 months; range, 1-71 months) with enucleation as primary treatment were imaged at 1.5T by using a dedicated surface coil. Signal-intensity voids indicating calcification on T2*WI were compared with ex vivo high-resolution CT, and correlation was scored by 2 independent observers as poor, good, or excellent. Other parameters included the shape and location of the signal-intensity voids. In 5 tumors, susceptibility-weighted images were evaluated. RESULTS: All calcifications visible on high-resolution CT could be matched with signal-intensity voids on T2*WI, and correlation was scored as excellent in 17 (77%) and good in 5 (23%) eyes. In total, 93% (25/27) of the signal-intensity voids inside the tumor correlated with calcifications compared with none (0/8) of the signal-intensity voids outside the tumor. Areas of nodular signal-intensity voids correlated with calcifications in 92% (24/26), and linear signal-intensity voids correlated with hemorrhage in 67% (6/9) of cases. The correlation of signal-intensity voids on SWI was better in 4 of 5 tumors compared with T2*WI. CONCLUSIONS: Signal-intensity voids on in vivo T2*WI correlate well with calcifications on ex vivo high-resolution CT in retinoblastoma. Gradient-echo sequences may be helpful in the differential diagnosis of retinoblastoma. The combination of funduscopy, sonography, and high-resolution MR imaging with gradient-echo sequences should become the standard diagnostic approach for retinoblastoma.


Assuntos
Calcinose/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Tomografia Computadorizada por Raios X , Calcinose/diagnóstico por imagem , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Masculino , Neoplasias da Retina/diagnóstico por imagem , Retinoblastoma/diagnóstico por imagem
7.
J Exp Med ; 211(7): 1465-83, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24935259

RESUMO

Myelin oligodendrocyte glycoprotein (MOG), a constituent of central nervous system myelin, is an important autoantigen in the neuroinflammatory disease multiple sclerosis (MS). However, its function remains unknown. Here, we show that, in healthy human myelin, MOG is decorated with fucosylated N-glycans that support recognition by the C-type lectin receptor (CLR) DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) on microglia and DCs. The interaction of MOG with DC-SIGN in the context of simultaneous TLR4 activation resulted in enhanced IL-10 secretion and decreased T cell proliferation in a DC-SIGN-, glycosylation-, and Raf1-dependent manner. Exposure of oligodendrocytes to proinflammatory factors resulted in the down-regulation of fucosyltransferase expression, reflected by altered glycosylation at the MS lesion site. Indeed, removal of fucose on myelin reduced DC-SIGN-dependent homeostatic control, and resulted in inflammasome activation, increased T cell proliferation, and differentiation toward a Th17-prone phenotype. These data demonstrate a new role for myelin glycosylation in the control of immune homeostasis in the healthy human brain through the MOG-DC-SIGN homeostatic regulatory axis, which is comprised by inflammatory insults that affect glycosylation. This phenomenon should be considered as a basis to restore immune tolerance in MS.


Assuntos
Encéfalo/imunologia , Moléculas de Adesão Celular/imunologia , Tolerância Imunológica/fisiologia , Inflamassomos/imunologia , Lectinas Tipo C/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Receptores de Superfície Celular/imunologia , Células Th17/imunologia , Animais , Encéfalo/citologia , Células CHO , Moléculas de Adesão Celular/genética , Proliferação de Células , Cricetinae , Cricetulus , Feminino , Humanos , Inflamassomos/genética , Mediadores da Inflamação/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Lectinas Tipo C/genética , Masculino , Glicoproteína Mielina-Oligodendrócito/genética , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/imunologia , Receptores de Superfície Celular/genética , Células Th17/citologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia
9.
Neuropathol Appl Neurobiol ; 39(4): 426-36, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22845849

RESUMO

AIMS: Diffuse intrinsic pontine glioma (DIPG) is a fatal paediatric malignancy. Tumour resection is not possible without serious morbidity and biopsies are rarely performed. The resulting lack of primary DIPG material has made preclinical research practically impossible and has hindered the development of new therapies for this disease. The aim of the current study was to address the lack of primary DIPG material and preclinical models by developing a multi-institutional autopsy protocol. METHODS: An autopsy protocol was implemented in the Netherlands to obtain tumour material within a brief post mortem interval. A team of neuropathologists and researchers was available at any time to perform the autopsy and process the material harvested. Whole brain autopsy was performed and primary DIPG material and healthy tissue were collected from all affected brain areas. Finally, the study included systematic evaluation by parents. RESULTS: Five autopsies were performed. The mean time interval between death and time of autopsy was 3 h (range 2-4). All tumours were graded as glioblastoma. None of the parents regretted their choice to participate, and they all derived comfort in donating tissue of their child in the hope to help future DIPG patients. In addition, we developed and characterized one of the first DIPG cell cultures from post mortem material. CONCLUSION: Here we show that obtaining post mortem DIPG tumour tissue for research purposes is feasible with short delay, and that the autopsy procedure is satisfying for participating parents and can be suitable for the development of preclinical DIPG models.


Assuntos
Autopsia/normas , Neoplasias do Tronco Encefálico/patologia , Glioma/patologia , Cultura Primária de Células/normas , Animais , Criança , Pré-Escolar , DNA de Neoplasias/biossíntese , DNA de Neoplasias/genética , Feminino , Humanos , Lactente , Masculino , Camundongos , Camundongos Nus , Pais , Ponte/patologia , RNA Neoplásico/biossíntese , RNA Neoplásico/genética
10.
Neth J Med ; 70(6): 278-80, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22859420

RESUMO

We present the case of a patient with clinical features of familial dysbetalipoproteinaemia (FD) including high levels of total cholesterol, hypertriglyceridaemia and the presence of palmar xanthomas. Whereas genotype analysis identified the APOE3E3 isoform, sequence analysis revealed the presence of one APOE1 allele due to a mutation, p.Lys164Glu, which leads to loss of function of apolipoprotein E (ApoE), a rare cause of dominant FD.


Assuntos
Hiperlipoproteinemia Tipo III , Mutação , Colesterol , Humanos , Hipertrigliceridemia
11.
AJNR Am J Neuroradiol ; 33(11): 2129-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22627800

RESUMO

BACKGROUND AND PURPOSE: Noninvasive evaluation of retinoblastoma treatment response has become more important due to increased use of eye-sparing treatments. We evaluated the relation between DCE-MR imaging and histopathologic parameters to determine the value of DCE-MR imaging in assessing tumor angiogenesis and prognostic features. MATERIALS AND METHODS: Fifteen consecutive patients with retinoblastoma (mean age, 24 months; range, 2-70 months) undergoing enucleation as the primary treatment (15 eyes) were scanned at 1.5T by using dedicated surface coils. Pretreatment DCE-MR imaging of the most affected eye was evaluated by 2 observers by using curve-pattern analysis, with the first 5 minutes of each curve and the full time-series described as κ(5min) and κ(17min), respectively. Assessed histopathologic and immunologic parameters included optic nerve invasion, choroid invasion, MVD, tumor necrosis, and expression of VEGF and Flt-1. RESULTS: The median value of κ(5min) was 1.28 (range, 0.87-2.07) and correlated positively with MVD (P = .008). The median value of κ(17min) was 1.33 (range, 0.35-3.08) and correlated negatively with tumor necrosis (P = .002). Other histopathologic and immunohistopathologic parameters did not correlate with DCE-MR imaging parameters. Interobserver agreement was 0.53 for κ(5min) and 0.91 for κ(17min). CONCLUSIONS: In retinoblastoma, the early phase of the DCE time curve positively correlates with MVD, while the presence of late enhancement is correlated with necrosis. Thus, the potential for DCE-MR imaging to noninvasively assess tumor angiogenesis and necrosis in retinoblastoma is promising and warrants further investigation.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/complicações , Neovascularização Patológica/patologia , Neoplasias da Retina/complicações , Neoplasias da Retina/patologia , Retinoblastoma/complicações , Retinoblastoma/patologia , Criança , Pré-Escolar , Meios de Contraste , Feminino , Humanos , Lactente , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
12.
Toxicol Lett ; 213(1): 39-44, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-21810456

RESUMO

Coal tar ointments (CTO) are frequently used in the treatment of psoriasis and eczema, but CTO contain carcinogenic polycyclic aromatic hydrocarbons (PAH). PAH are absorbed and metabolized in the skin. In psoriasis, the skin barrier is altered and therefore, absorption and metabolism of PAH may differ from healthy skin. In this study, levels of urinary 1-hydroxypyrene and PAH-DNA adducts in the skin were studied in psoriatic patients and healthy volunteers. Three punch biopsies were taken from the lower back of 10 male volunteers and from a psoriatic plaque in 10 male patients. A surface of 6.25 cm(2) was treated with CTO. After 96 h CTO was removed and another three skin biopsies were collected from the treated area. DNA was isolated from skin biopsies and urine was collected during and after the exposure period. After 24h, a twofold lower 1-hydroxypyrene urinary excretion was observed in patients compared to healthy volunteers and after 48 h, this difference reached statistical significance (p<0.05). Over 96 h the median level of the sum of PAH-DNA adducts, analyzed by (32)P-post-labeling, increased from 3.5 before CTO administration to 21.1 adducts per 10(8) nucleotides in volunteers, and from 1.0 to 3.6 adducts per 10(8) nucleotides in patients. At 96 h, PAH-DNA levels were higher in healthy volunteers than in patients (p<0.05). Biomarkers for uptake, bioavailability and bioactivation of PAH were lower in patients compared to volunteers. These data suggest a lower risk of carcinogenic effects of CTO in psoriatic skin compared to healthy skin.


Assuntos
Alcatrão/farmacocinética , Adutos de DNA/análise , Psoríase/tratamento farmacológico , Pirenos/análise , Pele/química , Adolescente , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Alcatrão/efeitos adversos , Alcatrão/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/metabolismo , Adulto Jovem
13.
AJNR Am J Neuroradiol ; 33(1): 110-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22033715

RESUMO

BACKGROUND AND PURPOSE: Retinoblastoma may exhibit variable hyperintensities on DWI, resulting in different values in the ADC maps, depending on their histology and cellularity. However, EP-based DWI has susceptibility artifacts and image distortions, which make DWI of the orbit a challenging technique. The aim of this study was to investigate the feasibility of single-shot turbo spin-echo (HASTE) DWI in the evaluation of children with retinoblastoma and to assess the value of ADC maps in differentiating viable and necrotic tumor tissue. MATERIALS AND METHODS: Two radiologists assessed conventional MR images, DWI, and ADC maps of 17 patients with retinoblastoma (n = 17 eyes). Non-EP DWI was performed by using a HASTE sequence with b-values of 0 and 1000 s/mm(2). ADC values were measured for enhancing and nonenhancing tumor tissue. ADC maps were compared with histopathologic findings regarding tumor differentiation and viability. RESULTS: On DWI, vital tumor tissue showed hyperintensity with negligible intensity of surrounding vitreous. The difference in mean (range) ADC values between enhancing (1.03 [0.72-1.22] × 10(-3) mm(2) s(-1)) and nonenhancing (1.47 [0.99-1.80] × 10(-3) mm(2) s(-1)) parts of retinoblastoma was statistically significant (P < .0005). Nonenhancing tumor parts showed a significantly lower ADC compared with vitreous (2.67 [2.24-3.20]×10(-3) mm(2) s(-1)) (P < .0005) and subretinal fluid (2.20 [1.76-2.96] × 10(-3) mm(2) s(-1)) (P < .0005). Histopathologically, low ADC values (enhancing tumor part) correlated to viable tumor tissue, whereas intermediate ADC values (nonenhancing tumor parts) correlated to necrotic tumor tissue. CONCLUSIONS: HASTE DWI allowed adequate characterization of retinoblastoma, and ADC is a helpful tool to differentiate viable and necrotic tumor tissue and might be valuable in monitoring the response to eye-preserving therapies.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Marcadores de Spin
14.
Physiol Res ; 60(Suppl 1): S49-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21777034

RESUMO

Over a century ago, hyperplasia and hypertrophy of astrocytes was noted as a histopathological hallmark of multiple sclerosis and was hypothesized to play an important role in the development and course of this disease. However until today, the factual contribution of astrocytes to multiple sclerosis is elusive. Astrocytes may play an active role during degeneration and demyelination by controlling local inflammation in the CNS, provoking damage of oligodendrocytes and axons, and glial scarring but might also be beneficial by creating a permissive environment for remyelination and oligodendrocyte precursor migration, proliferation, and differentiation. Recent findings from our lab suggest that brain lipid binding protein (FABP7) is implicated in the course of multiple sclerosis and the regulation of astrocyte function. The relevance of our findings and data from other groups are highlighted and discussed in this paper in the context of myelin repair.


Assuntos
Astrócitos/metabolismo , Proteínas de Transporte/metabolismo , Doenças Desmielinizantes/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Esclerose Múltipla/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Animais , Astrócitos/patologia , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Proteína 7 de Ligação a Ácidos Graxos , Humanos , Esclerose Múltipla/patologia , Bainha de Mielina/metabolismo
15.
Brain Behav Immun ; 25(8): 1554-68, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21620951

RESUMO

Several lines of evidence indicate that remyelination represents one of the most effective mechanisms to achieve axonal protection. For reasons that are not yet understood, this process is often incomplete or fails in multiple sclerosis (MS). Activated astrocytes appear to be able to boost or inhibit endogenous repair processes. A better understanding of remyelination in MS and possible reasons for its failure is needed. Using the well-established toxic demyelination cuprizone model, we created lesions with either robust or impaired endogenous remyelination capacity. Lesions were analyzed for mRNA expression levels by Affymetrix GeneChip® arrays. One finding was the predominance of immune and stress response factors in the group of genes which were classified as remyelination-supporting factors. We further demonstrate that lesions with impaired remyelination capacity show weak expression of the radial-glia cell marker brain lipid binding protein (BLBP, also called B-FABP or FABP7). The expression of BLBP in activated astrocytes correlates with the presence of oligodendrocyte progenitor cells. BLBP-expressing astrocytes are also detected in experimental autoimmune encephalomyelitis during the remission phase. Furthermore, highest numbers of BLBP-expressing astrocytes were evident in lesions of early MS, whereas significantly less are present at the rim of (chronic)-active lesions from patients with long disease duration. Transfection experiments show that BLBP regulates growth factor expression in U87 astrocytoma cells. In conclusion, we provide evidence that expression of BLBP in activated astrocytes negatively correlates with disease duration and in parallel with remyelination failure.


Assuntos
Astrócitos/metabolismo , Proteínas de Transporte/biossíntese , Doenças Desmielinizantes/metabolismo , Proteínas de Ligação a Ácido Graxo/biossíntese , Esclerose Múltipla/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Adulto , Idoso , Animais , Western Blotting , Contagem de Células , Linhagem Celular Tumoral , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Encefalomielite Autoimune Experimental/metabolismo , Proteína 7 de Ligação a Ácidos Graxos , Feminino , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator 2 de Crescimento de Fibroblastos/genética , Técnica Indireta de Fluorescência para Anticorpo , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Osteopontina/biossíntese , Fator de Crescimento Derivado de Plaquetas/biossíntese , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Transfecção
16.
J Crohns Colitis ; 4(6): 687-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21122583
17.
AJNR Am J Neuroradiol ; 31(2): 237-45, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19833805

RESUMO

BACKGROUND AND PURPOSE: AES contrast-enhancement is recognized in a substantial number of retinoblastoma-affected eyes. We retrospectively investigated the histopathologic basis of AES contrast-enhancement on MR images in retinoblastoma. MATERIALS AND METHODS: Pretreatment contrast-enhanced MR images were obtained from 42 children with retinoblastoma. Forty-two enucleated eyes were included in this study, AES enhancement was evaluated by using a 3-point score, and these data were correlated with clinical, MR imaging, and histopathologic findings. Additionally, 14 specimens were immunohistochemically analyzed for CD31, VEGF, and Flt-1 expression. Statistical correlations with AES enhancement were assessed by using a linear-by-linear association test and univariate and multivariate ordinal regressions. RESULTS: The degree of abnormal AES enhancement was moderate in 15 (36%) eyes and strong in 14 (33%) eyes, whereas 13 (31%) eyes showed normal AES enhancement. In multivariate analysis, the degree of AES enhancement showed statistically significant correlations with iris surface-vessel count (P = .05) and optic nerve invasion (P = .04) in the enucleated eye and with tumor volume (P = .02) as detected on MR imaging. No significant associations between AES enhancement and VEGF expression in the iris were observed. Flt-1 (P = .04) staining in iris stroma and IA as detected with CD31 staining (P = .009) both yielded a statistically significant positive correlation with abnormal AES enhancement. CONCLUSIONS: The degree of abnormal AES enhancement on MR imaging in retinoblastoma reflects angiogenesis in the iris. AES enhancement is also a hallmark of advanced retinoblastoma because its degree correlates with tumor volume and optic nerve invasion.


Assuntos
Câmara Anterior/patologia , Meios de Contraste , Neoplasias Oculares/patologia , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/patologia , Retinoblastoma/patologia , Biópsia , Pré-Escolar , Enucleação Ocular , Neoplasias Oculares/irrigação sanguínea , Neoplasias Oculares/metabolismo , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Lactente , Masculino , Neovascularização Patológica/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Retinoblastoma/irrigação sanguínea , Retinoblastoma/metabolismo , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
18.
Neuropathol Appl Neurobiol ; 35(3): 283-95, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19473295

RESUMO

BACKGROUND: In multiple sclerosis (MS) myelin debris has been observed within MS lesions, in cerebrospinal fluid and cervical lymph nodes, but the route of myelin transport out of the brain is unknown. Drainage of interstitial fluid from the brain parenchyma involves the perivascular spaces and leptomeninges, but the presence of myelin debris in these compartments has not been described. AIMS: To determine whether myelin products are present in the meninges and perivascular spaces of MS patients. METHODS: Formalin-fixed brain tissue containing meninges from 29 MS patients, 9 non-neurological controls, 6 Alzheimer's disease, 5 stroke, 5 meningitis and 7 leucodystrophy patients was investigated, and immunohistochemically stained for several myelin proteins [proteolipid protein (PLP), myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG) and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase)]. On brain material from MS patients and (non)neurological controls, PLP immunostaining was used to systematically investigate the presence of myelin debris in the meninges, using a semiquantitative scale. RESULTS: Extensive extracellular presence of myelin particles, positive for PLP, MBP, MOG and CNPase in the leptomeninges of MS patients, was observed. Myelin particles were also observed in perivascular spaces of MS patients. Immunohistochemical double-labelling for macrophage and dendritic cell markers and PLP confirmed that the vast majority of myelin particles were located extracellularly. Extracellular myelin particles were virtually absent in meningeal tissue of non-neurological controls, Alzheimer's disease, stroke, meningitis and leucodystrophy cases. CONCLUSIONS: In MS leptomeninges and perivascular spaces, abundant extracellular myelin can be found, whereas this is not the case for controls and other neurological disease. This may be relevant for understanding sustained immunogenicity or, alternatively, tolerogenicity in MS.


Assuntos
Espaço Extracelular/química , Meninges/química , Meninges/patologia , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Proteínas da Mielina/análise , Bainha de Mielina/patologia , Adolescente , Adrenoleucodistrofia/metabolismo , Adrenoleucodistrofia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Criança , Pré-Escolar , Células Dendríticas/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Masculino , Meningite/metabolismo , Meningite/patologia , Pessoa de Meia-Idade , Bainha de Mielina/química , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
19.
BJOG ; 116(1): 55-61, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19016685

RESUMO

OBJECTIVE: Primary postpartum haemorrhage (PPH) is a major cause of maternal morbidity and mortality around the world. Most patients can be managed conservatively, but patients with intractable bleeding require more aggressive treatment. In these cases uterine artery embolisation (UAE) has proven to be a useful tool to control PPH. The reported success rate of UAE is over 90% with only minor complications. In this case series we studied the effectiveness and complications of UAE. DESIGN: Retrospective analysis of a case series. SETTING: Case series in a large peripheral hospital in the Netherlands. SAMPLE: Eleven patients who were treated with UAE for intractable PPH from November 2004 to February 2008. METHODS: In this paper we review the results of all patients treated with UAE for intractable PPH in our hospital and focus on the two cases with adverse outcomes. MAIN OUTCOME MEASURES: Effectiveness, causes of failure of UAE, complications. RESULTS: Nine out of eleven patients were treated successfully with UAE. One patient needed an emergency hysterectomy for intractable bleeding. In the aftermath she developed a vesicovaginal fistula (VVF). Another patient suffered a major thrombo-embolic event of the right leg, for which she underwent embolectomies and despite fasciotomy a necrotectomy. CONCLUSIONS: UAE is a valuable tool in managing major PPH and in most cases it can replace surgery and thus prevent sacrification of the uterus. However, due to blood supply of the uterus by one of the ovarian or aberrant arteries, UAE might fail to control the bleeding. In addition, serious complications such as a thrombo-embolic event or VVF may occur. We hereby present a case of migration of an embolus from the site of re-embolisation into the femoral artery requiring immediate intervention to prevent the loss of the lower leg. This complication demonstrates that gelatine sponge particles could migrate from the internal iliac artery into the external iliac artery.


Assuntos
Hemorragia Pós-Parto/etiologia , Embolização da Artéria Uterina/efeitos adversos , Útero/irrigação sanguínea , Adulto , Meios de Contraste/efeitos adversos , Feminino , Esponja de Gelatina Absorvível/efeitos adversos , Humanos , Histerectomia/efeitos adversos , Artéria Ilíaca , Perna (Membro)/irrigação sanguínea , Hemorragia Pós-Parto/cirurgia , Gravidez , Reoperação/efeitos adversos , Retratamento , Estudos Retrospectivos , Resultado do Tratamento , Tromboembolia Venosa/etiologia , Fístula Vesicovaginal/etiologia
20.
J Clin Pathol ; 62(3): 275-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19017681

RESUMO

AIMS: The aims of this study were to determine: (1) which consent procedures patients prefer for future medical research with tissue stored following surgery; (2) the percentage of patients who choose not to provide consent for research with their stored tissue; (3) the reasons given for denying such tissue use. METHODS: Patients (n = 103) from the Vrije Universiteit Medical Centre, an academic hospital in The Netherlands, who had recently undergone surgery for breast or colorectal cancer were mailed a questionnaire about preferences for consent regimens. RESULTS: Seventy-six patients (74%) completed the questionnaire. Only two patients (3%) chose not to provide consent for research with their stored tissue. The majority of patients (60%) preferred an "opt-out plus" procedure that included receiving active, verbal information to "one-time general consent" (11%) or to an "opt-out" procedure without verbal notification (5%). Only 3% indicated a wish to be asked for consent for each new research project and 21% did not know what they preferred or had no preference. There were no significant associations observed between preference for the various consent regimens and age, sex, educational level or personal sense of ownership of the stored tissue. CONCLUSION: Patients prefer an opt-out plus procedure that includes the provision of explicit, verbal and written information. Less than 5% of patients decline to consent to the use of their stored tissue for research purposes.


Assuntos
Consentimento Livre e Esclarecido/ética , Neoplasias/psicologia , Satisfação do Paciente , Bancos de Tecidos/ética , Adulto , Idoso , Atitude Frente a Saúde , Pesquisa Biomédica/ética , Comportamento de Escolha , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/cirurgia , Países Baixos , Educação de Pacientes como Assunto/métodos
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