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1.
Artigo em Inglês | MEDLINE | ID: mdl-38396261

RESUMO

PURPOSE: According to the World Health Organization classification for tumors of the central nervous system, mutation status of the isocitrate dehydrogenase (IDH) genes has become a major diagnostic discriminator for gliomas. Therefore, imaging-based prediction of IDH mutation status is of high interest for individual patient management. We compared and evaluated the diagnostic value of radiomics derived from dual positron emission tomography (PET) and magnetic resonance imaging (MRI) data to predict the IDH mutation status non-invasively. METHODS: Eighty-seven glioma patients at initial diagnosis who underwent PET targeting the translocator protein (TSPO) using [18F]GE-180, dynamic amino acid PET using [18F]FET, and T1-/T2-weighted MRI scans were examined. In addition to calculating tumor-to-background ratio (TBR) images for all modalities, parametric images quantifying dynamic [18F]FET PET information were generated. Radiomic features were extracted from TBR and parametric images. The area under the receiver operating characteristic curve (AUC) was employed to assess the performance of logistic regression (LR) classifiers. To report robust estimates, nested cross-validation with five folds and 50 repeats was applied. RESULTS: TBRGE-180 features extracted from TSPO-positive volumes had the highest predictive power among TBR images (AUC 0.88, with age as co-factor 0.94). Dynamic [18F]FET PET reached a similarly high performance (0.94, with age 0.96). The highest LR coefficients in multimodal analyses included TBRGE-180 features, parameters from kinetic and early static [18F]FET PET images, age, and the features from TBRT2 images such as the kurtosis (0.97). CONCLUSION: The findings suggest that incorporating TBRGE-180 features along with kinetic information from dynamic [18F]FET PET, kurtosis from TBRT2, and age can yield very high predictability of IDH mutation status, thus potentially improving early patient management.

2.
Eur J Nucl Med Mol Imaging ; 50(1): 103-114, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36048259

RESUMO

PURPOSE: Progressive supranuclear palsy (PSP) is primary 4-repeat tauopathy. Evidence spanning from imaging studies indicate aberrant connectivity in PSPs. Our goal was to assess functional connectivity network alterations in PSP patients and the potential link between regional tau-burden and network-level functional connectivity using the next-generation tau PET tracer [18F]PI-2620 and resting-state functional MRI (fMRI). MATERIAL AND METHODS: Twenty-four probable PSP patients (70.9 ± 6.9 years, 13 female), including 14 Richardson syndrome (RS) and 10 non-RS phenotypes, underwent [18F]PI-2620 PET/MRI imaging. Distribution volume ratios (DVRs) were estimated using non-invasive pharmacokinetic modeling. Resting-state fMRI was also acquired in these patients as well as in thirteen older non-AD MCI reference group (64 ± 9 years, 4 female). The functional network was constructed using 141 by 141 region-to-region functional connectivity metrics (RRC) and network-based statistic was carried out (connection threshold p < 0.001, cluster threshold pFDR < 0.05). RESULTS: In total, 9870 functional connections were analyzed. PSPs compared to aged non-AD MCI reference group expressed aberrant connectivity evidenced by the significant NBS network consisting of 89 ROIs and 118 connections among them (NBS mass 4226, pFDR < 0.05). Tau load in the right globus pallidus externus (GPe) and left dentate nucleus (DN) showed significant effects on functional network connectivity. The network linked with increased tau load in the right GPe was associated with hyperconnectivity of low-range intra-opercular connections (NBS mass 356, pFDR < 0.05), while the network linked with increased tau load in the left cerebellar DN was associated with cerebellar hyperconnectivity and cortico-cerebellar hypoconnectivity (NBS mass 517, pFDR < 0.05). CONCLUSIONS: PSP patients show altered functional connectivity. Network incorporating deep gray matter structures demonstrate hypoconnectivity, cerebellum hyperconnectivity, while cortico-cortical connections show variable changes. Tau load in the right GPe and left DN is associated with functional networks which strengthen low-scale intra-opercular and intra-cerebellar connections and weaken opercular-cerebellar connections. These findings support the concept of tau load-dependent functional network changes in PSP, by that providing evidence for downstream effects of neuropathology on brain functionality in this primary tauopathy.


Assuntos
Paralisia Supranuclear Progressiva , Tauopatias , Feminino , Humanos , Cerebelo/metabolismo , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons/métodos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Proteínas tau/metabolismo , Masculino , Pessoa de Meia-Idade , Idoso
3.
J Neurooncol ; 155(1): 35-43, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34546498

RESUMO

PURPOSE: The outcomes of five fraction stereotactic radiotherapy (hfSRT) following brain metastasectomy were evaluated and compared with published series. METHODS: 30 Gy in 5 fractions HfSRT prescribed to the surgical cavity was reduced to 25 Gy if the volume of 'brain-GTV' receiving 20 Gy exceeded 20 cm3. Endpoints were local recurrence, nodular leptomeningeal recurrence, new brain metastases and radionecrosis. The literature was searched for reports of clinical and dosimetric outcomes following postoperative hfSRT in 3-5 fractions. RESULTS: 39 patients with 40 surgical cavities were analyzed. Cavity local control rate at 1 year was 33/40 (82.5%). 3 local failures followed 30 Gy/5 fractions and 4 with 25 Gy/5 fractions. The incidence of leptomeningeal disease (LMD) was 7/40 (17.5%). No grade 3-4 toxicities, particularly no radionecrosis, were reported. The incidence of distant brain metastases was 15/40 (37.5%). The median overall survival was 15 months. Across 13 published series, the weighted mean local control was 83.1% (adjusted for sample size), the mean incidence of LMD was 14.9% (7-34%) and the mean rate of radionecrosis was 10.3% (0-20.6%). CONCLUSION: Postoperative hfSRT can be delivered with 25-30 Gy in 5 fractions with efficacy in excess of 82% and no significant toxicity when the dose to 'brain-GTV' does not exceed 20 cm3.


Assuntos
Neoplasias Encefálicas , Metastasectomia , Lesões por Radiação , Radiocirurgia , Encéfalo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Humanos , Neoplasias Meníngeas , Hipofracionamento da Dose de Radiação , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
5.
Eur J Nucl Med Mol Imaging ; 47(6): 1368-1380, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31486876

RESUMO

BACKGROUND: The 18-kDa translocator protein (TSPO) is overexpressed in brain tumours and represents an interesting target for glioma imaging. 18F-GE-180, a novel TSPO ligand, has shown improved binding affinity and a high target-to-background contrast in patients with glioblastoma. However, the association of uptake characteristics on TSPO PET using 18F-GE-180 with the histological WHO grade and molecular genetic features so far remains unknown and was evaluated in the current study. METHODS: Fifty-eight patients with histologically validated glioma at initial diagnosis or recurrence were included. All patients underwent 18F-GE-180 PET, and the maximal and mean tumour-to-background ratios (TBRmax, TBRmean) as well as the PET volume were assessed. On MRI, presence/absence of contrast enhancement was evaluated. Imaging characteristics were correlated with neuropathological parameters (i.e. WHO grade, isocitrate dehydrogenase (IDH) mutation, O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation and telomerase reverse transcriptase (TERT) promoter mutation). RESULTS: Six of 58 patients presented with WHO grade II, 16/58 grade III and 36/58 grade IV gliomas. An (IDH) mutation was found in 19/58 cases, and 39/58 were classified as IDH-wild type. High 18F-GE-180-uptake was observed in all but 4 cases (being WHO grade II glioma, IDH-mutant). A high association of 18F-GE-180-uptake and WHO grades was seen: WHO grade IV gliomas showed the highest uptake intensity compared with grades III and II gliomas (median TBRmax 5.15 (2.59-8.95) vs. 3.63 (1.85-7.64) vs. 1.63 (1.50-3.43), p < 0.001); this association with WHO grades persisted within the IDH-wild-type and IDH-mutant subgroup analyses (p < 0.05). Uptake intensity was also associated with the IDH mutational status with a trend towards higher 18F-GE-180-uptake in IDH-wild-type gliomas in the overall group (median TBRmax 4.67 (1.56-8.95) vs. 3.60 (1.50-7.64), p = 0.083); however, within each WHO grade, no differences were found (e.g. median TBRmax in WHO grade III glioma 4.05 (1.85-5.39) vs. 3.36 (2.32-7.64), p = 1.000). No association was found between uptake intensity and MGMT or TERT (p > 0.05 each). CONCLUSION: Uptake characteristics on 18F-GE-180 PET are highly associated with the histological WHO grades, with the highest 18F-GE-180 uptake in WHO grade IV glioblastomas and a PET-positive rate of 100% among the investigated high-grade gliomas. Conversely, all TSPO-negative cases were WHO grade II gliomas. The observed association of 18F-GE-180 uptake and the IDH mutational status seems to be related to the high inter-correlation of the IDH mutational status and the WHO grades.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Carbazóis , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Biologia Molecular , Mutação , Gradação de Tumores , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Receptores de GABA
6.
Eur J Nucl Med Mol Imaging ; 46(3): 580-590, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30244386

RESUMO

BACKGROUND: PET represents a valuable tool for glioma imaging. In addition to amino acid tracers such as 18F-FET, PET targeting the 18-kDa mitochondrial translocator-protein (TSPO) is of high interest for high-grade glioma (HGG) imaging due to its upregulation in HGG cells. 18F-GE-180, a novel TSPO ligand, has shown a high target-to-background contrast in HGG. Therefore, we intra-individually compared its uptake characteristics to dynamic 18F-FET PET and contrast-enhanced MRI in patients with HGG. METHODS: Twenty HGG patients (nine IDH-wildtype, 11 IDH-mutant) at initial diagnosis (n = 8) or recurrence (n = 12) were consecutively included and underwent 18F-GE-180 PET, dynamic 18F-FET PET, and MRI. The maximal tumour-to-background ratios (TBRmax) and biological tumour volumes (BTV) were evaluated in 18F-GE-180 and 18F-FET PET. Dynamic 18F-FET PET analysis included the evaluation of minimal time-to-peak (TTPmin). In MRI, the volume of contrast-enhancement was delineated (VOLCE). Volumes were spatially correlated using the Sørensen-Dice coefficient. RESULTS: The median TBRmax tended to be higher in 18F-GE-180 PET compared to 18F-FET PET [4.58 (2.33-8.95) vs 3.89 (1.56-7.15); p = 0.062] in the overall group. In subgroup analyses, IDH-wildtype gliomas showed a significantly higher median TBRmax in 18F-GE-180 PET compared to 18F-FET PET [5.45 (2.56-8.95) vs 4.06 (1.56-4.48); p = 0.008]; by contrast, no significant difference was observed in IDH-mutant gliomas [3.97 (2.33-6.81) vs 3.79 (2.01-7.15) p = 1.000]. Only 5/20 cases showed higher TBRmax in 18F-FET PET compared to 18F-GE-180 PET, all of them being IDH-mutant gliomas. No parameter in 18F-GE-180 PET correlated with TTPmin (p > 0.05 each). There was a tendency towards higher median BTVGE-180 [32.1 (0.4-236.0) ml] compared to BTVFET [19.3 (0.7-150.2) ml; p = 0.062] with a moderate spatial overlap [median Sørensen-Dice coefficient 0.55 (0.07-0.85)]. In MRI, median VOLCE [9.7 (0.1-72.5) ml] was significantly smaller than both BTVFET and BTVGE180 (p < 0.001 each), leading to a poor spatial correlation with BTVGE-180 [0.29 (0.01-0.48)] and BTVFET [0.38 (0.01-0.68)]. CONCLUSION: PET with 18F-GE-180 and 18F-FET provides differing imaging information in HGG dependent on the IDH-mutational status, with diverging spatial overlap and vast exceedance of contrast-enhancement in MRI. Combined PET imaging might reveal new insights regarding non-invasive characterization of tumour heterogeneity and might influence patients' management.


Assuntos
Carbazóis , Glioma/diagnóstico por imagem , Glioma/patologia , Tomografia por Emissão de Pósitrons/métodos , Tirosina/análogos & derivados , Adulto , Idoso , Transporte Biológico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Carbazóis/metabolismo , Feminino , Glioma/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Projetos Piloto , Polimorfismo Genético , Traçadores Radioativos , Receptores de GABA/genética , Carga Tumoral , Tirosina/metabolismo
7.
Case Rep Womens Health ; 19: e00065, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30094193

RESUMO

We report the initial diagnosis in a 28-year-old nulliparous woman of a primary mediastinal B-cell lymphoma in late pregnancy. For several weeks the patient had had symptoms of mediastinal obstruction, such as dyspnea, cough, swelling of the face and upper limbs. However, these symptoms had been misattributed to the pregnancy and a common cold. Due to a rapid decline in the patient's cardiovascular performance, she was transferred to the closest perinatal center in the 34th week of pregnancy, whereupon a cesarean section was performed. The diagnosis of a primary mediastinal B-cell lymphoma was made postpartum from a biopsy. This case emphasizes the importance of timely antenatal investigation in pregnant women with symptoms consistent with mediastinal obstruction. Thoracic ultrasonography can be a valuable tool for the detection of tumor-associated pleural and pericardial effusions.

8.
Eur J Nucl Med Mol Imaging ; 45(8): 1423-1431, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29523925

RESUMO

PURPOSE: Expression of the translocator protein (TSPO) is upregulated in activated macrophages/microglia and is considered to be a marker of neuroinflammation. We investigated the novel TSPO ligand [18F]GE-180 in patients with relapsing-remitting multiple sclerosis (RRMS) to determine the feasibility of [18F]GE-180 PET imaging in RRMS patients and to assess its ability to detect active inflammatory lesions in comparison with the current gold standard, contrast-enhanced magnetic resonance imaging (MRI). METHODS: Nineteen RRMS patients were prospectively included in this study. All patients underwent TSPO genotyping and were classified as high-affinity, medium-affinity or low-affinity binders (HAB/MAB/LAB). PET scans were performed after administration of 189 ± 12 MBq [18F]GE-180, and 60-90 min summation images were used for visual analysis and assessment of standardized uptake values (SUV). The frontal nonaffected cortex served as a pseudoreference region (PRR) for evaluation of SUV ratios (SUVR). PET data were correlated with MRI signal abnormalities, i.e. T2 hyperintensity or contrast enhancement (CE). When available, previous MRI data were used to follow the temporal evolution of individual lesions. RESULTS: Focal lesions were identified as hot spots by visual inspection. Such lesions were detected in 17 of the 19 patients and overall 89 [18F]GE-180-positive lesions were found. TSPO genotyping revealed 11 patients with HAB status, 5 with MAB status and 3 with LAB status. There were no associations between underlying binding status (HAB, MAB and LAB) and the signal intensity in either lesions (SUVR 1.87 ± 0.43, 1.95 ± 0.48 and 1.86 ± 0.80, respectively; p = 0.280) or the PRR (SUV 0.36 ± 0.03, 0.40 ± 0.06 and 0.37 ± 0.03, respectively; p = 0.990). Of the 89 [18F]GE-180-positive lesions, 70 showed CE on MRI, while the remainder presented as T2 lesions without CE. SUVR were significantly higher in lesions with CE than in those without (2.00 ± 0.53 vs. 1.60 ± 0.15; p = 0.001). Notably, of 19 [18F]GE-180-positive lesions without CE, 8 previously showed CE, indicating that [18F]GE-180 imaging may be able to detect lesional activity that is sustained beyond the blood-brain barrier breakdown. CONCLUSION: [18F]GE-180 PET can detect areas of focal macrophage/microglia activation in patients with RRMS in lesions with and without CE on MRI. Therefore, [18F]GE-180 PET imaging is a sensitive and quantitative approach to the detection of active MS lesions. It may provide information beyond contrast-enhanced MRI and is readily applicable to all patients. [18F]GE-180 PET imaging is therefore a promising new tool for the assessment of focal inflammatory activity in MS.


Assuntos
Carbazóis , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Receptores de GABA/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla , Estudos Prospectivos , Adulto Jovem
9.
Eur J Nucl Med Mol Imaging ; 44(13): 2230-2238, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28821920

RESUMO

OBJECTIVE: The 18-kDa mitochondrial translocator protein (TSPO) was reported to be upregulated in gliomas. 18F-GE-180 is a novel 3rd generation TSPO receptor ligand with improved target-to-background contrast compared to previous tracers. In this pilot study, we compared PET imaging with 18F-GE-180 and MRI of patients with untreated and recurrent pretreated glioblastoma. METHODS: Eleven patients with histologically confirmed IDH wildtype gliomas (10 glioblastomas, 1 anaplastic astrocytoma) underwent 18F-GE-180 PET at initial diagnosis or recurrence. The PET parameters mean background uptake (SUVBG), maximal tumour-to-background ratio (TBRmax) and PET volume using different thresholds (SUVBG × 1.6, 1.8 and 2.0) were evaluated in the 60-80 min p.i. summation images. The different PET volumes were compared to the contrast-enhancing tumour volume on MRI. RESULTS: All gliomas were positive on 18F-GE-180 PET and were depicted with extraordinarily high tumour-to-background contrast (median SUVBG 0.47 (0.37-0.93), TBRmax 6.61 (3.88-9.07)). 18F-GE-180 uptake could be found even in areas without contrast enhancement on MRI, leading to significantly larger PET volumes than MRI-based volumes (median 90.5, 74.5, and 63.8 mL vs. 31.0 mL; p = 0.003, 0.004, 0.013). In percentage difference, the PET volumes were on average 179%, 135%, and 90% larger than the respective MRI volumes. The median spatial volumetric correlation (Sørensen-Dice coefficient) of PET volumes and MRI volumes prior to radiotherapy was 0.48, 0.54, and 0.58. CONCLUSION: 18F-GE-180 PET provides a remarkably high tumour-to-background contrast in untreated and pretreated glioblastoma and shows tracer uptake even beyond contrast enhancement on MRI. To what extent 18F-GE-180 uptake reflects the tumour extent of human gliomas and inflammatory cells remains to be evaluated in future prospective studies with guided stereotactic biopsies and correlation of histopathological results.


Assuntos
Carbazóis , Glioblastoma/diagnóstico por imagem , Glioblastoma/metabolismo , Tomografia por Emissão de Pósitrons , Receptores de GABA/metabolismo , Feminino , Humanos , Ligantes , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Recidiva
10.
Nervenarzt ; 88(2): 156-161, 2017 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-27913818

RESUMO

BACKGROUND: To this day the definite diagnosis of Alzheimer's disease still relies on post-mortem histopathological detection of neurofibrillary tangles and beta-amyloid deposits. Amyloid positron emission tomography (PET) is a new diagnostic tool that enables the in vivo quantification of pathological beta-amyloid deposits. The aim of the current study was to evaluate to what extent 18F-florbetaben-PET (FBB-PET) influences the diagnosis of patients with dementia. MATERIAL AND METHODS: Imaging with FBB-PET was performed on 33 patients from our outpatient department for cognitive neurology. Beforehand all patients underwent a comprehensive clinical, neuropsychiatric and laboratory examination as well as imaging by means of magnetic resonance imaging (MRI) and fluorodeoxyglucose-PET. The working diagnoses before and after FBB-PET imaging were compared. RESULTS: 17 out of 33 patients were scored as FBB-PET positive. In four cases the initial diagnosis had to be changed to Alzheimer's disease (three cases) and cerebral amyloid angiopathy (one case) due to the positive FBB-PET scan. 16 patients showed a negative FBB-PET scan. In three patients the initial diagnosis of Alzheimer's disease could be ruled out due to the negative FBB-PET scan. Overall, in 7 out of 33 examined patients the initial diagnosis had to be changed because of the findings of the FBB-PET scan. In 24 patients the initial diagnosis was confirmed by the results of the FBB-PET scan. CONCLUSION: Amyloid-PET is currently no standard procedure in the diagnosis of dementia; however, it can be a helpful additional diagnostic tool when used according to the "Appropriate Use Criteria" and the S3 guidelines on dementia in cases of unclear clinical presentation, atypically early age of onset as well as in patients with persistent or progressive unexplained mild cognitive impairment. By facilitating early diagnosis amyloid-PET imaging allows patient selection for therapeutic drug trials.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Compostos de Anilina/farmacocinética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Demência/diagnóstico por imagem , Demência/metabolismo , Estilbenos/farmacocinética , Adulto , Idoso , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
11.
Fortschr Neurol Psychiatr ; 84(8): 494-8, 2016 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-27570907

RESUMO

We report on a pair of siblings with frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) and a novel Thr462Lysfs mutation in the TANK-binding kinase 1 (TBK1) gene identified through the European Early-Onset Dementia Consortium. The patients presented at the age of 77 and 75 years and displayed dementia and bulbar symptoms as well as progressive paresis. After a progressive course, both of them died only a few months after diagnosis. Most recently, TBK1 mutations were identified in patients with FTD and ALS. A loss of expression of the mutant allele, leading to 50 % reduced TBK1 protein levels, seems to be causative. The occurrence of TBK1 mutations in FTD and ALS underlines the fact that FTD and ALS are part of the same disease spectrum. For future therapeutic trials, characterization of TBK1 mutation carriers in presymptomatic cohorts, such as the genetic frontotemporal dementia initiative (GENFI), is of great importance.


Assuntos
Alelos , Esclerose Amiotrófica Lateral/genética , Análise Mutacional de DNA , Demência Frontotemporal/genética , Irmãos , Idoso , Esclerose Amiotrófica Lateral/diagnóstico , Encéfalo/patologia , Comorbidade , Progressão da Doença , Feminino , Demência Frontotemporal/diagnóstico , Testes Genéticos , Humanos , Imageamento por Ressonância Magnética , Masculino , Exame Neurológico , Linhagem , Tomografia por Emissão de Pósitrons
13.
Mol Psychiatry ; 20(10): 1179-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26055427

RESUMO

In a positron-emission tomography (PET) study with the ß-amyloid (Aß) tracer [(18)F]-florbetaben, we previously showed that Aß deposition in transgenic mice expressing Swedish mutant APP (APP-Swe) mice can be tracked in vivo. γ-Secretase modulators (GSMs) are promising therapeutic agents by reducing generation of the aggregation prone Aß42 species without blocking general γ-secretase activity. We now aimed to investigate the effects of a novel GSM [8-(4-Fluoro-phenyl)-[1,2,4]triazolo[1,5-a]pyridin-2-yl]-[1-(3-methyl-[1,2,4]thiadiazol-5-yl)-piperidin-4-yl]-amine (RO5506284) displaying high potency in vitro and in vivo on amyloid plaque burden and used longitudinal Aß-microPET to trace individual animals. Female transgenic (TG) APP-Swe mice aged 12 months (m) were assigned to vehicle (TG-VEH, n=12) and treatment groups (TG-GSM, n=12), which received daily RO5506284 (30 mg kg(-1)) treatment for 6 months. A total of 131 Aß-PET recordings were acquired at baseline (12 months), follow-up 1 (16 months) and follow-up 2 (18 months, termination scan), whereupon histological and biochemical analyses of Aß were performed. We analyzed the PET data as VOI-based cortical standard-uptake-value ratios (SUVR), using cerebellum as reference region. Individual plaque load assessed by PET remained nearly constant in the TG-GSM group during 6 months of RO5506284 treatment, whereas it increased progressively in the TG-VEH group. Baseline SUVR in TG-GSM mice correlated with Δ%-SUVR, indicating individual response prediction. Insoluble Aß42 was reduced by 56% in the TG-GSM versus the TG-VEH group relative to the individual baseline plaque load estimates. Furthermore, plaque size histograms showed differing distribution between groups of TG mice, with fewer small plaques in TG-GSM animals. Taken together, in the first Aß-PET study monitoring prolonged treatment with a potent GSM in an AD mouse model, we found clear attenuation of de novo amyloidogenesis. Moreover, longitudinal PET allows non-invasive assessment of individual plaque-load kinetics, thereby accommodating inter-animal variations.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Placa Amiloide/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Animais , Estudos de Casos e Controles , Angiopatia Amiloide Cerebral/terapia , Modelos Animais de Doenças , Feminino , Estudos Longitudinais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Placa Amiloide/diagnóstico por imagem , Placa Amiloide/enzimologia , Placa Amiloide/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Estilbenos/síntese química , Estilbenos/farmacologia
14.
Eur Neuropsychopharmacol ; 25(6): 873-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25819144

RESUMO

Altered SERT and DAT availabilities during treatment with escitalopram were investigated with [(123)I]2ß-carbomethoxy-3ß-(4-iodophenyl)tropane (ß-CIT) SPECT in a series of patients fulfilling the criteria for unipolar major depressive disorder (MDD). 27 patients (10m, 42±16y) with diagnosis of MDD were recruited for the study. All patients underwent neuropsychiatric testing for assessment of Hamilton Depression (HAM-D) and Beck Depression Inventory (BDI) scores. At baseline, [(123)I]ß-CIT SPECT recordings were acquired 4h (SERT-weighted) and 20-24h p.i (DAT-weighted). Follow-up scans and neuropsychiatric testing were performed after six weeks of stable escitalopram medication. Voxel-wise parametric maps of specific/ non-specific ratios-1 (~BPND) were calculated. At baseline, DAT-weighted BPND was 5.06±0.81 in striatum and SERT-weighted BPND was 0.94±0.18 in thalamus. There were significant negative correlations with age for DAT in striatum (R=-0.60; p<0.01) and SERT in thalamus (R=-0.45; p<0.05). Under SSRI treatment there was an apparent 42% occupancy of SERT in thalamus (p<0.0001), whereas DAT availability increased significantly by 20% in striatum (p<0.001); higher apparent SERT occupancy in thalamus was associated with lesser DAT increase in striatum (R=-0.62; p<0.005). The low apparent SERT occupancy may be confounded by alterations in SERT expression during treatment. Thus, [(123)I]ß-CIT SPECT revealed age-dependent declines in DAT and SERT availabilities in un-medicated MDD patients, comparable to that seen previously in healthy controls. At follow-up, the SSRI-evoked increase in DAT was less pronounced in the older patients, even though apparent SERT occupancy and clinical improvement were not age-dependent. Present findings may have implications for escitalopram dosage and side effect profile in younger MDD patients.


Assuntos
Antidepressivos/uso terapêutico , Citalopram/uso terapêutico , Depressão/tratamento farmacológico , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Serotonina/metabolismo , Tropanos/farmacocinética , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Depressão/diagnóstico por imagem , Depressão/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Estatística como Assunto , Tomografia Computadorizada de Emissão de Fóton Único , Adulto Jovem
15.
Genet Mol Res ; 13(3): 7725-35, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25299086

RESUMO

Theobroma cacao L. contains more than 500 different chemical compounds some of which have been traditionally used for their antioxidant, anti-carcinogenic, immunomodulatory, vasodilatory, analgesic, and antimicrobial activities. Spontaneous aerobic fermentation of cacao husks yields a crude husk extract (CHE) with antimicrobial activity. CHE was fractioned by solvent partition with polar solvent extraction or by silica gel chromatography and a total of 12 sub-fractions were analyzed for chemical composition and bioactivity. CHE was effective against the yeast Saccharomyces cerevisiae and the basidiomycete Moniliophthora perniciosa. Antibacterial activity was determined using 6 strains: Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis (Gram-positive) and Pseudomonas aeruginosa, Klebsiella pneumoniae, and Salmonella choleraesuis (Gram-negative). At doses up to 10 mg/mL, CHE was not effective against the Gram-positive bacteria tested but against medically important P. aeruginosa and S. choleraesuis with a minimum inhibitory concentration (MIC) of 5.0 mg/mL. Sub-fractions varied widely in activity and strongest antibacterial activity was seen with CHE8 against S. choleraesuis (MIC of 1.0 mg/mL) and CHE9 against S. epidermidis (MIC of 2.5 mg/mL). All bioactive CHE fractions contained phenols, steroids, or terpenes, but no saponins. Fraction CHE9 contained flavonoids, phenolics, steroids, and terpenes, amino acids, and alkaloids, while CHE12 had the same compounds but lacked flavonoids.


Assuntos
Anti-Infecciosos/farmacologia , Cacau/química , Fermentação , Extratos Vegetais/farmacologia , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Cromatografia em Gel , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
16.
Geburtshilfe Frauenheilkd ; 74(6): 563-568, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24976638

RESUMO

Background: Administered either alone or in combination with various cytostatic, endocrine or targeted therapies, trastuzumab significantly improves the prognosis of patients with HER2-positive breast cancer. As trastuzumab is effective across multiple lines of therapy in the metastatic setting (treatment beyond progression: TBP), it is often administered over a long period of time. The aim of this study was to evaluate the tolerability and clinical practice of long-term trastuzumab administration (> 1 year) in metastatic breast cancer patients treated in a large university breast center. Methods: Metastatic breast cancer patients who received at least 18 cycles of trastuzumab administered every three weeks at the University Gynecological Hospital of Tuebingen between 1999 and 2012 were included in this retrospective study. Typical combination drugs, side effects, and the impact of administration on left ventricular ejection fraction (LVEF) were investigated. Results: 72 patients were eligible for inclusion in the study. The mean number of administrations was 50.14 (SD: 27.51). In 53 patients the principle of TBP was followed across an average of 2.4 therapy lines. Classic cardiac risk factors were present at the beginning of trastuzumab treatment in 34 patients (47 %). Seven patients (10 %) experienced a decrease in LVEF during treatment, 9 patients (13 %) had hypersensitivity reactions. Treatment was discontinued in two patients due to side effects (1â€Š× progressive LVEF decrease, 1â€Š× intolerance). Summary: The administration of trastuzumab across multiple lines of therapy was generally tolerated well. Cardiac risk factors were not a limiting factor. If regular cardiac monitoring is done, trastuzumab appears not only to improve survival but also helps preserve the quality of life of patients with HER2-positive metastatic breast cancer.

17.
Genet Mol Res ; 13(1): 2048-59, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24737430

RESUMO

We investigated the biodegradability of oil in mangrove sediment from Camamu Bay and measured its effect on the bacterial community. Microcosms of mangrove sediment were contaminated with 0.1, 0.5, 1, 2, and 5% (w/v) oil, and the microbial activity was compared to that in uncontaminated sediment. The evolution of CO2 and gas chromatography showed the mineralization of oil compounds, which could reach 100%. Bacterial diversity was determined by polymerase chain reaction using a set of primers for the V3 and V6-V8 regions of 16S rDNA. The band profile obtained by denaturing gradient gel electrophoresis of the amplicons that were obtained for the V3 region showed a negative correlation between band number and oil concentration, whereas that of the V6-V8 region showed a positive correlation between band numbers and oil concentration. The latter also gave similar results for microcosms that were contaminated with 2 and 5% oil. These results demonstrate the mangrove sediment's capacity to recover from oil contamination (in vitro) and suggest that native mangrove microorganisms contain enzymes necessary for the catabolism of oil.


Assuntos
Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Sedimentos Geológicos/microbiologia , Microbiota/fisiologia , Petróleo/metabolismo , Rhizophoraceae/microbiologia , Bactérias/classificação , Bactérias/genética , Baías , Brasil , Dióxido de Carbono/análise , Dióxido de Carbono/química , Análise por Conglomerados , Poluentes Ambientais/análise , Sedimentos Geológicos/química , Metagenoma , Petróleo/análise , RNA Ribossômico 16S
18.
Genet Mol Res ; 12(4): 4422-33, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24222222

RESUMO

The increasing world production of biodiesel has resulted in an accumulation of crude glycerol as the major byproduct. This could be used as carbon source for industrial microbiology, with economic and environmental advantages for the biodiesel industry. We explored an Atlantic Rainforest soil sample to search for crude glycerol-degrading microorganisms. Microcosms of this soil were established containing minimal medium + 8% crude glycerol (w/w); the biological activity was measured by respirometry. High CO2 levels were found in some of the crude glycerol microcosms, suggesting the activity of microorganisms capable of degrading this residue. In an attempt to isolate and cultivate these microorganisms in vitro, aliquots of the soil suspension were plated on minimal medium containing 10% crude glycerol (v/v). Out of 19 morphologically distinct isolates, 12 bacteria and 6 yeasts were identified by PCR from universal primers 16S and 26S rDNA, respectively. Optical density readings revealed growth differences among cultures. Two yeasts and three bacteria with distinct growth profiles stood out and appeared to have potential for liquid fermentation of crude glycerol. The yeasts adapted rapidly, but produced relatively little biomass. Opposite tendencies were found in the bacteria. Amplicon sequencing placed the bacterial isolates as close to Staphylococcus arlettae, Pseudomonas citronellolis, and Bacillus megaterium, and the yeasts to Trichosporon moniliiforme and Meyerozyma guilliermondii. We concluded that these species have potential for use in crude glycerol bioreactors and for bioremediation processes.


Assuntos
Bactérias/crescimento & desenvolvimento , Glicerol/metabolismo , Microbiologia do Solo , Leveduras/crescimento & desenvolvimento , Bactérias/genética , Bactérias/isolamento & purificação , Biocombustíveis , Brasil , Dióxido de Carbono/metabolismo , Meios de Cultura , Fermentação , Tipagem Molecular , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , Árvores/microbiologia , Leveduras/genética , Leveduras/isolamento & purificação
19.
Genet Mol Res ; 12(3): 2611-7, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23546981

RESUMO

Changes in intestinal microbial flora during a 4-week period of Salmonella enterica serovar Enteritidis colonization in resistant mice (latent carrier animals) were evaluated using a culture independent method involving denaturing gradient gel electrophoresis. The contents of the ileocecal portion of the intestines produced 26 bands. Fifty-seven percent of the bands were expressed in more than 80% of the samples. Forty percent of the bands present in the negative control were common to all samples, and 60% differed from those obtained 12 h and 1, 5, 10, and 28 days post-inoculation (PI). A dendrogram distinguished the negative control as the external group, and 2 clusters were formed with 76% similarity, separating the 12-h PI and 3-day PI time points from the others. These groupings were also revealed through multivariate analysis in a principal component analysis and the Venn diagram. The production of interferon γ 12 h and 3 days PI may explain this brief imbalance in microbiota that was quickly reversed in the subsequent days. These findings demonstrate that S. enterica serovar Enteritidis can colonize the gut and persist in balance with the microbiota of resistant hosts.


Assuntos
Ceco/microbiologia , DNA Bacteriano/análise , Íleo/microbiologia , Microbiota , Infecções por Salmonella/microbiologia , Animais , Eletroforese em Gel de Gradiente Desnaturante , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética , Salmonella enteritidis/genética
20.
Genet Mol Res ; 12(4): 6619-28, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24391008

RESUMO

Autophagy is defined as an intracellular system of lysosomal degradation in eukaryotic cells, and the genes involved in this process are conserved from yeast to humans. Among these genes, ATG8 encodes a ubiquitin-like protein that is conjugated to a phosphatidylethanolamine (PE) membrane by the ubiquitination system. The Atg8p-PE complex is important in initiating the formation of the autophagosome and thus plays a critical role in autophagy. In silico modeling of Atg8p of Moniliophthora perniciosa revealed its three-dimensional structure and enabled comparison with its Saccharomyces cerevisiae homologue ScAtg8p. Some common and distinct features were observed between these two proteins, including the conservation of residues required to allow the interaction of α-helix1 with the ubiquitin core. However, the electrostatic potential surfaces of these helices differ, implying particular roles in selecting specific binding partners. The proposed structure was validated by the programs PROCHECK 3.4, ANOLEA, and QMEAN, which demonstrated 100% of amino acids located in favorable regions with low total energy. Our results showed that MpAtg8p contains the same functional domains (3 α-helices and 4 ß-sheets) and is similar in structure as the ScAtg8p yeast. Both proteins have many conserved sequences in common, and therefore, their proposed three-dimensional models show similar configuration.


Assuntos
Agaricales/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/ultraestrutura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Autofagia , Família da Proteína 8 Relacionada à Autofagia , Modelos Moleculares , Dados de Sequência Molecular , Fosfatidiletanolaminas/metabolismo , Estrutura Terciária de Proteína , Alinhamento de Sequência , Ubiquitinação/genética
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