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1.
Acta Neuropathol ; 148(1): 2, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980441

RESUMO

Proteolytic cell surface release ('shedding') of the prion protein (PrP), a broadly expressed GPI-anchored glycoprotein, by the metalloprotease ADAM10 impacts on neurodegenerative and other diseases in animal and in vitro models. Recent studies employing the latter also suggest shed PrP (sPrP) to be a ligand in intercellular communication and critically involved in PrP-associated physiological tasks. Although expectedly an evolutionary conserved event, and while soluble forms of PrP are present in human tissues and body fluids, for the human body neither proteolytic PrP shedding and its cleavage site nor involvement of ADAM10 or the biological relevance of this process have been demonstrated thus far. In this study, cleavage site prediction and generation (plus detailed characterization) of sPrP-specific antibodies enabled us to identify PrP cleaved at tyrosin 226 as the physiological and apparently strictly ADAM10-dependent shed form in humans. Using cell lines, neural stem cells and brain organoids, we show that shedding of human PrP can be stimulated by PrP-binding ligands without targeting the protease, which may open novel therapeutic perspectives. Site-specific antibodies directed against human sPrP also detect the shed form in brains of cattle, sheep and deer, hence in all most relevant species naturally affected by fatal and transmissible prion diseases. In human and animal prion diseases, but also in patients with Alzheimer`s disease, sPrP relocalizes from a physiological diffuse tissue pattern to intimately associate with extracellular aggregated deposits of misfolded proteins characteristic for the respective pathological condition. Findings and research tools presented here will accelerate novel insight into the roles of PrP shedding (as a process) and sPrP (as a released factor) in neurodegeneration and beyond.


Assuntos
Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide , Doenças Neurodegenerativas , Humanos , Proteína ADAM10/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Proteínas Priônicas/metabolismo , Proteínas de Membrana/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Anticorpos
2.
Radiol Oncol ; 58(2): 186-195, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38643513

RESUMO

BACKGROUND: Non-cardia gastric cancer remains a major cause of cancer-related mortality worldwide, despite declining incidence rates in many industrialized countries. The development of intestinal-type gastric cancer occurs through a multistep process in which normal mucosa is sequentially transformed into hyperproliferative epithelium, followed by metaplastic processes leading to carcinogenesis. Chronic infection with Helicobacter pylori is the primary etiological agent that causes chronic inflammation of the gastric mucosa, induces atrophic gastritis, and can lead to intestinal metaplasia and dysplasia. Both intestinal metaplasia and dysplasia are precancerous lesions, in which gastric cancer is more likely to occur. Atrophic gastritis often improves after eradication of Helicobacter pylori; however, the occurrence of intestinal metaplasia has been traditionally regarded as "the point of no return" in the carcinogenesis sequence. Helicobacter pylori eradication heals non-atrophic chronic gastritis, may lead to regression of atrophic gastritis, and reduces the risk of gastric cancer in patients with these conditions. In this article, we discuss the pathogenesis, epigenomics, and reversibility of intestinal metaplasia and briefly touch upon potential treatment strategy. CONCLUSIONS: Gastric intestinal metaplasia no longer appears to be an irreversible precancerous lesion. However, there are still many controversies regarding the improvement of intestinal metaplasia after Helicobacter pylori eradication.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Metaplasia , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/etiologia , Metaplasia/patologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/patologia , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/microbiologia , Carcinogênese/patologia , Gastrite Atrófica/patologia , Gastrite Atrófica/microbiologia , Mucosa Gástrica/patologia , Mucosa Gástrica/microbiologia , Intestinos/patologia , Intestinos/microbiologia
3.
Cancers (Basel) ; 12(12)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333941

RESUMO

The aim of this clinical study was to investigate the effectiveness and long-term safety of electrochemotherapy as an emerging treatment for HCC in patients not suitable for other treatment options. A prospective phase II clinical study was conducted in patients with primary HCC who were not suitable for other treatment options according to the Barcelona Clinic Liver Cancer classification. A total of 24 patients with 32 tumors were treated by electrochemotherapy. The procedure was effective, feasible, and safe with some procedure-related side effects. The responses of the 32 treated nodules were: 84.4% complete response (CR), 12.5% partial response (PR), and 3.1% stable disease (SD). The treatment was equally effective for nodules located centrally and peripherally. Electrochemotherapy provided a durable response with local tumor control over 50 months of observation in 78.0% of nodules. The patient responses were: 79.2% CR and 16.6% PR. The median progression-free survival was 12 months (range 2.7-50), and the overall survival over 5 years of observation was 72.0%. This prospective phase II clinical study showed that electrochemotherapy was an effective, feasible, and safe option for treating HCC in patients not suitable for other treatment options.

4.
Radiol Oncol ; 54(3): 347-352, 2020 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-32562533

RESUMO

Background Electrochemotherapy is an effective treatment of colorectal liver metastases and hepatocellular carcinoma (HCC) during open surgery. The minimally invasive percutaneous approach of electrochemotherapy has already been performed but not on HCC. The aim of this study was to demonstrate the feasibility, safety and effectiveness of electrochemotherapy with percutaneous approach on HCC. Patient and methods The patient had undergone the transarterial chemoembolization and microwave ablation of multifocal HCC in segments III, V and VI. In follow-up a new lesion was identified in segment III, and recognized by multidisciplinary team to be suitable for minimally invasive percutaneous electrochemotherapy. The treatment was performed with long needle electrodes inserted by the aid of image guidance. Results The insertion of electrodes was feasible, and the treatment proved safe and effective, as demonstrated by control magnetic resonance imaging. Conclusions Minimally invasive, image guided percutaneous electrochemotherapy is feasible, safe and effective in treatment of HCC.


Assuntos
Bleomicina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Eletroquimioterapia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Técnicas de Ablação , Idoso , Angiografia , Carcinoma Hepatocelular/diagnóstico por imagem , Terapia Combinada , Tomografia Computadorizada de Feixe Cônico , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Micro-Ondas/uso terapêutico , Radiografia Intervencionista
5.
Front Med (Lausanne) ; 7: 598438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33425946

RESUMO

Introduction: The optimal treatment for small, asymptomatic, nonfunctioning pancreatic neuroendocrine neoplasms (NF-PanNEN) is still controversial. European Neuroendocrine Tumor Society (ENETS) guidelines recommend a watchful strategy for asymptomatic NF-PanNEN <2 cm of diameter. Several retrospective series demonstrated that a non-operative management is safe and feasible, but no prospective studies are available. Aim of the ASPEN study is to evaluate the optimal management of asymptomatic NF-PanNEN ≤2 cm comparing active surveillance and surgery. Methods: ASPEN is a prospective international observational multicentric cohort study supported by ENETS. The study is registered in ClinicalTrials.gov with the identification code NCT03084770. Based on the incidence of NF-PanNEN the number of expected patients to be enrolled in the ASPEN study is 1,000 during the study period (2017-2022). Primary endpoint is disease/progression-free survival, defined as the time from study enrolment to the first evidence of progression (active surveillance group) or recurrence of disease (surgery group) or death from disease. Inclusion criteria are: age >18 years, the presence of asymptomatic sporadic NF-PanNEN ≤2 cm proven by a positive fine-needle aspiration (FNA) or by the presence of a measurable nodule on high-quality imaging techniques that is positive at 68Gallium DOTATOC-PET scan. Conclusion: The ASPEN study is designed to investigate if an active surveillance of asymptomatic NF-PanNEN ≤2 cm is safe as compared to surgical approach.

6.
Radiol Oncol ; 52(4): 443-452, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30511938

RESUMO

Background Dendritic cells play crucial roles in the control of inflammation and immune tolerance in the gut. We aimed to investigate the effects of tumor necrosis factor alpha (TNFa) inhibitors on intestinal dendritic cells in patients with inflammatory bowel disease and the potential role of intestinal dendritic cells in predicting the response to treatment. Patients and methods Intestinal biopsies were obtained from 30 patients with inflammatory bowel disease before and after treatment with TNFa inhibitors. The proportions of lamina propria dendritic cell phenotypes were analysed using flow cytometry. Disease activity was endoscopically assessed at baseline and after the induction treatment. Results At baseline, the proportion of conventional dendritic cells was higher in the inflamed mucosa (7.8%) compared to the uninflamed mucosa (4.5%) (p = 0.003), and the proportion of CD103+ dendritic cells was lower in the inflamed mucosa (47.1%) versus the uninflamed mucosa (57.3%) (p = 0.03). After 12 weeks of treatment, the proportion of conventional dendritic cells in the inflamed mucosa decreased from 7.8% to 4.5% (p = 0.014), whereas the proportion of CD103+ dendritic cells remained unchanged. Eighteen out of 30 (60%) patients responded to their treatment by week 12. Responders had a significantly higher proportion of conventional dendritic cells (9.16% vs 4.4%, p < 0.01) with higher expression of HLA-DR (median fluorescent intensity [MFI] 12152 vs 8837, p = 0.038) in the inflamed mucosa before treatment compared to nonresponders. Conclusions A proportion of conventional dendritic cells above 7% in the inflamed inflammatory bowel disease mucosa before treatment predicts an endoscopic response to TNFa inhibitors.


Assuntos
Adalimumab/uso terapêutico , Células Dendríticas/imunologia , Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Infliximab/uso terapêutico , Adulto , Biópsia , Estudos de Casos e Controles , Colonoscopia , Feminino , Humanos , Mucosa Intestinal/imunologia , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/antagonistas & inibidores
7.
Nutrition ; 47: 110-114, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29310849

RESUMO

Dietary supplements known as "fat burners" are typically marketed with claims of increasing energy expenditure through alterations in fat metabolism. They are marketed as natural products and their use is thus perceived as a safe body weight reduction strategy. We report on five episodes of liver injury in four patients. Liver injury was associated with consumption of different commercially available fat burners: Green tea extract (Camellia sinensis), Garcinia gummi-gutta, green coffee beans, and spirulina (blue-green algae). The patients were admitted to the Department of Gastroenterology and Hepatology at the University Medical Center Ljubljana, in Slovenia, from May 2010 to July 2015. The first patient developed acute liver failure and had to be treated by liver transplantation. Second patient developed acute hepatitis that resolved spontaneously. Another patient required multiple surgical procedures due to severe hemorrhage after liver biopsy. The last patient was treated for two separate episodes of fat burner-induced liver injury after ingesting two different products, in 2010 and 2015. Liver biopsy was performed in all patients and histopathologic examination revealed no other cause of liver injury. Viral, autoimmune, and metabolic liver diseases were excluded, making unsupervised consumption of fat burners the most likely causative agent.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Suplementos Nutricionais/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Hipolipemiantes/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Doença Aguda , Camellia sinensis , Café , Feminino , Garcinia , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/efeitos adversos , Sementes , Spirulina
8.
J Med Chem ; 60(21): 8741-8757, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-28921979

RESUMO

Deposition of aggregates of hyperphosphorylated tau protein is a hallmark of tauopathies like Alzheimer and many other neurodegenerative diseases. A sensitive and selective method of in vivo detection of tau-aggregate presence and distribution could provide the means of an early diagnosis of tau-associated diseases. Furthermore, the use of selective molecular probes that enable histochemical differentiation of protein aggregates post-mortem would be advantageous for the insight into the properties of tau protein aggregates. We chose to design new molecular probes based on the structure of 2-(1-(6-((2-[18F]fluoroethyl)(methyl)amino)-2-naphthyl)ethylidene)malononitrile to investigate their likelihood of fitting into VQIVYK tau protein binding channel model. In a modular approach, using cross-coupling reactions, we synthesized a series of candidates, radiolabeled them with fluorine-18 radioisotope, and determined their physicochemical and in vitro binding properties. Herein we report the synthesis of a series of molecular probes capable of detection of tau protein deposits in vitro.


Assuntos
Desenho de Fármacos , Sondas Moleculares/síntese química , Tauopatias/diagnóstico , Proteínas tau/análise , Sítios de Ligação , Radioisótopos de Flúor , Humanos , Marcação por Isótopo , Nitrilas/química
9.
Radiol Oncol ; 49(4): 365-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26834523

RESUMO

BACKGROUND: The aim of the study was to investigate how the expression of tumor markers p21, p27, p53, cyclin D1, EGFR, Ki-67, and CD31 influenced the outcome of advanced inoperable oropharyngeal carcinoma patients, treated with concomitant radiochemotherapy. PATIENTS AND METHODS: The pretreatment biopsy specimens of 74 consecutive patients with inoperable stage IV oropharyngeal squamous cell carcinoma treated with concomitant radiochemotherapy were in retrospective study processed by immunochemistry for p21, p27, p53, cyclin D1, EGFR, Ki-67, and CD31. Disease-free survival (DFS) was assessed according to the expression of tumor markers. RESULTS: Patients with a high expression of p21 (≥10%), p27 (>50%), Ki-67 (>50%), CD31 (>130 vessels/mm2) and low expression of p53 (<10%), cyclin D1 (<10%) and EGFR (<10%) (favorable levels - FL) had better DFS than patients with a low expression of p21 (<10%), p27 (≤50%), Ki-67 (≤50%), CD31 (<130 vessels/mm2) and high expression of p53 (≥10%), cyclin D1 (≥10%) and EGFR (≥10%) (unfavorable levels - UL). However, statistical significance in survival between FL and UL was achieved only for p27 and cyclin D1. DFS significantly decreased with an increasing number of markers with an unfavorable level per tumor (1-4 vs. 5-7) (78% vs. 32%, respectively; p = 0.004). The number of markers per tumor with UL of expression retained prognostic significance also in multivariate analysis. CONCLUSIONS: Statistical significance in survival between FL and UL emerged only for p27 and cyclin D1. The number of markers per tumor with UL of expression was an independent prognostic factor for an adverse outcome.

10.
J Alzheimers Dis ; 36(2): 261-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23568102

RESUMO

This work is aimed at correlating pre-mortem [18F]FDDNP positron emission tomography (PET) scan results in a patient with dementia with Lewy bodies (DLB), with cortical neuropathology distribution determined postmortem in three physical dimensions in whole brain coronal sections. Analysis of total amyloid-ß (Aß) distribution in frontal cortex and posterior cingulate gyrus confirmed its statistically significant correlation with cortical [18F]FDDNP PET binding values (distribution volume ratios, DVR) (p < 0.001, R = 0.97, R2 = 0.94). Neurofibrillary tangle (NFT) distribution correlated significantly with cortical [18F]FDDNP PET DVR in the temporal lobe (p < 0.001, R = 0.87, R2 = 0.76). Linear combination of Aß and NFT densities was highly predictive of [18F]FDDNP PET DVR through all analyzed regions of interest (p < 0.0001, R = 0.92, R2 = 0.85), and both densities contributed significantly to the model. Lewy bodies were present at a much lower level than either Aß or NFTs and did not significantly contribute to the in vivo signal. [18F]FDG PET scan results in this patient were consistent with the distinctive DLB pattern of hypometabolism. This work offers a mapping brain model applicable to all imaging probes for verification of imaging results with Aß and/or tau neuropathology brain distribution using immunohistochemistry, fluorescence microscopy, and autoradiography.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral/metabolismo , Imageamento Tridimensional , Doença por Corpos de Lewy/patologia , Proteínas tau/metabolismo , Idoso , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Masculino , Emaranhados Neurofibrilares , Nitrilas , Tomografia por Emissão de Pósitrons , Mudanças Depois da Morte , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Tomógrafos Computadorizados
11.
Eur Arch Otorhinolaryngol ; 270(12): 3143-51, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23545885

RESUMO

Lysosomal proteases cathepsins B and L (CB, CL) and their endogenous inhibitors stefins A and B (SA, SB) are associated with tumor cell invasion and metastasis. The purpose of this study was to determine the immunohistochemical (IHC) localization of these parameters in tissue sections of 65 patients with operable head and neck squamous cell carcinoma (HNSCC) and to evaluate the prognostic significance of the observed IHC reactions. In SCC cells, a dot-like staining pattern for CB and CL was especially polarized in the perinuclear area and for stefins the characteristic IHC pattern was a diffuse cytoplasmic reaction. Higher SA immunoreactivity scores were found prognostically advantageous in univariate survival analysis [locoregional control (LRC), P = 0.003; disease-free survival (DFS), P = 0.023; disease-specific survival (DSS), P = 0.030] and appeared significant for predicting LRC (P = 0.019) in a multivariate setting. Among node-positive extracapsular extension-negative patients, SA positivity correlated with a favorable outcome (LRC, P = 0.094; DFS, P = 0.013; DSS, P = 0.012). In conclusion, SA immunoreactivity in tumor cells was related to a favorable prognosis. In the neck node-positive extracapsular extension-negative subgroup, SA immunoreactivity scores can be used to identify patients at increased risk for disease relapse.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Cistatinas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/terapia , Catepsinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Prognóstico
12.
Int J Pediatr Otorhinolaryngol ; 76(10): 1392-400, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22835930

RESUMO

OBJECTIVE: To investigate the music perception abilities of prelingually deaf children with cochlear implants, in comparison to a group of normal-hearing children, and to consider the factors that contribute to music perception. METHODS: The music perception abilities of 39 prelingually deaf children with unilateral cochlear implants were compared to the abilities of 39 normal hearing children. To assess the music listening abilities, the MuSIC perception test was adopted. The influence of the child's age, age at implantation, device experience and type of sound-processing strategy on the music perception were evaluated. The effects of auditory performance, nonverbal intellectual abilities, as well as the child's additional musical education on music perception were also considered. RESULTS: Children with cochlear implants and normal hearing children performed significantly differently with respect to rhythm discrimination (55% vs. 82%, p<0.001), instrument identification (57% vs. 88%, p<0.001) and emotion rating (p=0.022). However we found no significant difference in terms of melody discrimination and dissonance rating between the two groups. There was a positive correlation between auditory performance and melody discrimination (r=0.27; p=0.031), between auditory performance and instrument identification (r=0.20; p=0.059) and between the child's grade (mark) in school music classes and melody discrimination (r=0.34; p=0.030). In children with cochlear implant only, the music perception ability assessed by the emotion rating test was negatively correlated to the child's age (r(S)=-0.38; p=0.001), age at implantation (r(S)=-0.34; p=0.032), and device experience (r(S)=-0.38; p=0.019). The child's grade in school music classes showed a positive correlation to music perception abilities assessed by rhythm discrimination test (r(S)=0.46; p<0.001), melody discrimination test (r(S)=0.28; p=0.018), and instrument identification test (r(S)=0.23; p=0.05). CONCLUSIONS: As expected, there was a marked difference in the music perception abilities of prelingually deaf children with cochlear implants in comparison to the group of normal hearing children, but not for all the tests of music perception. Additional multi-centre studies, including a larger number of participants and a broader spectrum of music subtests, considering as many as possible of the factors that may contribute to music perception, seem reasonable.


Assuntos
Percepção Auditiva , Implantes Cocleares , Surdez/cirurgia , Música , Adolescente , Fatores Etários , Criança , Educação , Emoções , Feminino , Humanos , Masculino
13.
Int J Biol Markers ; 26(4): 247-54, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22139645

RESUMO

The hypothesis was tested that a specific pattern in the cysteine cathepsin/inhibitor ratio is associated with the development of more aggressive tumor cell phenotypes in squamous cell carcinoma of the head and neck (SCCHN). For this purpose commercially available ELISAs were used to determine the concentrations of cysteine cathepsins B and L and their inhibitors, stefins A and B, in cytosols of nontumorous mucosa and primary tumors from 92 patients. Using the stefin A concentration difference in matched pairs of tissue samples as a stratifying variable, 53 cases were found to be upregulated (higher concentrations in tumor samples than in nontumorous mucosa) and 39 cases downregulated. Disease recurrence was more frequent in the downregulated group than in the upregulated group (35.9% vs 11.3%, p=0.009), which resulted in significantly different 5-year disease-free survival rates (61.2% vs 88%, p=0.004). The consistency of these results was confirmed by repeating the analysis in an independent group of patients (the reference group). The presented results suggest that in patients with SCCHN, specific patterns in the proteolytic profile of cysteine proteases and their inhibitors are associated with the development of distinctly aggressive tumor cell phenotypes and are of prognostic value.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Cisteína Proteases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Catepsinas/metabolismo , Cistatinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço
14.
Brain Pathol ; 20(2): 419-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19725833

RESUMO

In vivo amyloid PET imaging was carried out on six symptomatic and asymptomatic carriers of PRNP mutations associated with the Gerstmann-Sträussler-Scheinker (GSS) disease, a rare familial neurodegenerative brain disorder demonstrating prion amyloid neuropathology, using 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([F-18]FDDNP). 2-Deoxy-2-[F-18]fluoro-d-glucose PET ([F-18]FDG) and magnetic resonance imaging (MRI) scans were also performed in each subject. Increased [F-18]FDDNP binding was detectable in cerebellum, neocortex and subcortical areas of all symptomatic gene carriers in close association with the experienced clinical symptoms. Parallel glucose metabolism ([F-18]FDG) reduction was observed in neocortex, basal ganglia and/or thalamus, which supports the close relationship between [F-18]FDDNP binding and neuronal dysfunction. Two asymptomatic gene carriers displayed no cortical [F-18]FDDNP binding, yet progressive [F-18]FDDNP retention in caudate nucleus and thalamus was seen at 1- and 2-year follow-up in the older asymptomatic subject. In vitro FDDNP labeling experiments on brain tissue specimens from deceased GSS subjects not participating in the in vivo studies indicated that in vivo accumulation of [F-18]FDDNP in subcortical structures, neocortices and cerebellum closely related to the distribution of prion protein pathology. These results demonstrate the feasibility of detecting prion protein accumulation in living patients with [F-18]FDDNP PET, and suggest an opportunity for its application to follow disease progression and monitor therapeutic interventions.


Assuntos
Amiloide/metabolismo , Encéfalo/metabolismo , Doença de Gerstmann-Straussler-Scheinker/metabolismo , Príons/metabolismo , Adulto , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Fluordesoxiglucose F18 , Seguimentos , Doença de Gerstmann-Straussler-Scheinker/diagnóstico por imagem , Doença de Gerstmann-Straussler-Scheinker/genética , Glucose/metabolismo , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Nitrilas , Tomografia por Emissão de Pósitrons , Proteínas Priônicas , Príons/genética , Proteínas tau/metabolismo
15.
Int J Radiat Oncol Biol Phys ; 72(2): 365-72, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18394816

RESUMO

PURPOSE: To evaluate the toxicity and efficacy of concomitant chemoradiotherapy with mitomycin C and cisplatin in the treatment of advanced unresectable squamous cell carcinoma of the head and neck. PATIENTS AND METHODS: Treatment consisted of conventional radiotherapy (70 Gy in 35 fractions), mitomycin C 15 mg/m(2) IV, applied after the delivery of 10 Gy, and cisplatin at an initial dose of 10 mg/m(2)/d IV, applied during the last 10 fractions of irradiation ("chemoboost"). The cisplatin dose was escalated with respect to the toxic side effects by 2 mg/m(2)/d up to the maximum tolerated dose (MTD) or at the most 14 mg/m(2)/d (Phase I study), which was tested in the subsequent Phase II study. RESULTS: All 36 patients had Stage T4 and/or N3 disease, and the majority had oropharyngeal (50%) or hypopharyngeal (39%) primary tumors. Six patients were treated at each of the three cisplatin dose levels tested (Phase I study). Dose-limiting toxicity was not reached even at 14 mg/m(2)/d of cisplatin, which was determined as the MTD and tested in an additional 18 patients (Phase II study). After a median follow-up time of 48 months, 4-year locoregional control, failure-free, and overall survival rates were 30%, 14%, and 20%, respectively. In 24 patients treated at the cisplatin dose level of 14 mg/m(2)/d, the corresponding rates were 40%, 20%, and 22%, respectively. CONCLUSION: Concomitant chemoradiotherapy with mitomycin C and cisplatin "chemoboost" at 14 mg/m(2)/d is feasible, with encouraging survival results if the extremely poor disease profile of the treated patients is considered.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/secundário , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada/métodos , Estudos de Viabilidade , Humanos , Dose Máxima Tolerável , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Análise de Sobrevida
16.
J Neurochem ; 104(6): 1553-64, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17996023

RESUMO

Conversion of the native, predominantly alpha-helical conformation of prion protein (PrP) into the beta-stranded conformation is characteristic for the transmissible spongiform encephalopathies such as Creutzfeld-Jakob disease. Curcumin, an extended planar molecule and a dietary polyphenol, inhibits in vitro conversion of PrP and formation of protease resistant PrP in neuroblastoma cell lines. Curcumin recognizes the converted beta-form of the PrP both as oligomers and fibrils but not the native form. Curcumin binds to the prion fibrils in the left-handed chiral arrangement as determined by circular dichroism. We show that curcumin labels the plaques of the brain sections of variant Creutzfeld-Jakob disease cases and stains the same structures as antibodies against the PrP. In contrast to thioflavin T, curcumin also binds to the alpha-helical intermediate of PrP present at acidic pH at stoichiometry of 1 : 1. Congo red competes with curcumin for binding to the alpha-intermediate as well as to the beta-form of PrP but is toxic and binds also to the native form of PrP. We therefore show that the partially unfolded structural intermediate of the PrP can be targeted by non-toxic compound of natural origin.


Assuntos
Síndrome de Creutzfeldt-Jakob/tratamento farmacológico , Síndrome de Creutzfeldt-Jakob/metabolismo , Curcumina/farmacologia , Proteínas PrPSc/metabolismo , Amiloide/metabolismo , Ligação Competitiva , Cerebelo/metabolismo , Cerebelo/patologia , Dicroísmo Circular , Síndrome de Creutzfeldt-Jakob/patologia , Curcumina/química , Curcumina/metabolismo , Desenho de Fármacos , Humanos , Técnicas In Vitro , Proteínas PrPSc/química , Estrutura Secundária de Proteína , Estereoisomerismo
17.
Int J Radiat Oncol Biol Phys ; 68(5): 1335-41, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17418975

RESUMO

PURPOSE: The aim of this study was to test the hypothesis about the protective role of high stefin A and stefin B concentrations in operable carcinoma of the head and neck. METHODS AND MATERIALS: Stefins A and B concentrations were measured in tissue cytosols of nontumorous mucosa and primary tumors from 92 patients. For quantitative analysis of stefins in tumor cytosols, commercially available enzyme-linked immunosorbent assays were used. RESULTS: Stefin A was upregulated in 53 patients (higher concentrations were measured in tumor samples than in nontumorous mucosa) and was downregulated in 39 patients. The corresponding numbers for stefin B were 49 and 43, respectively. A significantly higher proportion of downregulated cases were found among patients with disease re-appearance. In the Cox model, high stefin A concentrations appeared as independent predictors for favorable disease-free survival. Assuming a "broken stick" model, a significant increase in the recurrence rate after the threshold of 1063 ng/mgp (the 64th percentile in the group) was found, the hazard ratio reaching 3% of the reference value with doubling of the level of stefin A. These results were reconfirmed after pooling the data with two historical data sets into a uniform series involving 182 patients. CONCLUSIONS: A group of patients at high risk for disease progression was identified, characterized by the downregulated stefin A protein in the tumor compared with the nontumorous mucosa. Stefin A was recognized as a promising candidate marker for prognosis in patients with operable carcinoma of the head and neck.


Assuntos
Carcinoma de Células Escamosas/sangue , Cistatinas/sangue , Neoplasias de Cabeça e Pescoço/sangue , Proteínas de Neoplasias/sangue , Adulto , Idoso , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Cistatina A , Cistatina B , Feminino , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Estatísticas não Paramétricas
18.
Int J Radiat Oncol Biol Phys ; 67(3): 685-90, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17197122

RESUMO

PURPOSE: The long term results and patterns of failure in patients with squamous cell head and neck carcinoma (SCHNC) treated in a prospective randomized trial in which concomitant postoperative radiochemotherapy with Mitomycin C and Bleomycin (CRT) was compared with radiotherapy only (RT), were analyzed. PATIENTS AND METHODS: Between March 1997 and December 2001, 114 eligible patients with Stage III or IV SCHNC were randomized. Primary surgical treatment was performed with curative intent in all patients. Patients in both groups were postoperatively irradiated to the total dose of 56-70 Gy. Chemotherapy included Mitomycin C 15 mg/m2 after 10 Gy and 5 mg of Bleomycin twice weekly during irradiation. Median follow-up was 76 months (48-103 months). RESULTS: At 5 years in the RT and CRT arms, the locoregional control was 65% and 88% (p = 0.026), disease-free survival 33% and 53% (p = 0.035), and overall survival 37% and 55% (p = 0.091) respectively. Patients who benefited from chemotherapy were those with high-risk factors. The probability of distant metastases was 22% in RT and 20% in CRT arm (p = 0.913), of grade III or higher late toxicity 19% in RT and 26% in CRT arm (p = 0.52) and of thyroid dysfunction 36% in RT and 56% in CRT arm (p = 0.24). The probability to develop a second primary malignancy (SPM) was 34% in the RT and 8% in the CRT arm (p = 0.023). One third of deaths were due to infection, but there was no difference between the 2 groups. CONCLUSION: With concomitant radiochemotherapy, locoregional control and disease free survival were significantly improved. Second primary malignancies in the CRT arm compared to RT arm were significantly less frequent. The high probability of post treatment hypothyroidism in both arms warrants regular laboratory evaluation.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Terapia Combinada/métodos , Intervalo Livre de Doença , Seguimentos , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Mitomicina/administração & dosagem , Segunda Neoplasia Primária/etiologia , Probabilidade , Estudos Prospectivos , Dosagem Radioterapêutica , Falha de Tratamento
19.
Brain Pathol ; 16(2): 124-30, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16768752

RESUMO

Deposition of conformationally altered proteins prominently characterizes pathogenesis and pathomorphology of a number of neurodegenerative disorders. 2-(1-{6-[(2-[F-18]fluoroethyl) (methyl)amino]-2-naphthyl} ethylidene) malononitrile ([F-18]FDDNP), a hydrophobic, viscosity-sensitive, solvent-sensitive, fluorescent imaging probe has been used with positron emission tomography to visualize brain pathology in the living brain of Alzheimer disease (AD) patients. Its non-radiofluorinated analog FDDNP was shown to label senile plaques and neurofibrillary tangles (NFTs) in brain tissue sections. This work aimed at evaluating FDDNP labeling of various protein deposits in fixed, paraffin-embedded brain tissue sections of selected neurodegenerative disorders: AD, cerebral amyloid angiopathy (CAA), transmissible spongiform encephalopathies, progressive supranuclear palsy (PSP), Pick disease (PiD), Parkinson disease, dementia with Lewy bodies, multiple system atrophy (MSA). Cerebral hypertensive vascular hyalinosis (HVH) was used as negative control. Significant agreement between amyloid histochemical properties and FDDNP labeling of the deposits was established. FDDNP labeling showed high positive predictive value for birefringence in senile plaques and NFTs in AD, prion plaques and amyloid deposits in CAA. No FDDNP labeled structures were observed in HVH, PSP, PiD or MSA tissue sections. Our findings may be of significant value for the detection of neuropathological aggregates with [F-18]FDDNP in some of these disorders in the living brain of human subjects.


Assuntos
Radioisótopos de Flúor , Técnicas de Sonda Molecular , Naftalenos , Doenças Neurodegenerativas/diagnóstico , Emaranhados Neurofibrilares/metabolismo , Placa Amiloide/metabolismo , Birrefringência , Vermelho Congo/química , Corantes Fluorescentes/química , Radioisótopos de Flúor/química , Humanos , Naftalenos/química , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/diagnóstico por imagem , Doenças Neurodegenerativas/metabolismo , Emaranhados Neurofibrilares/química , Nitrilas/química , Placa Amiloide/química , Valor Preditivo dos Testes , Cintilografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Clin Chim Acta ; 344(1-2): 155-61, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15149884

RESUMO

BACKGROUND: The balance between proteinases of various classes and their inhibitors was found to be of critical importance for local invasion and metastasizing of tumor cells. The aim of the present study was to determine the changes in the serum cystatin C concentration in patients with squamous cell carcinoma of the head and neck. METHODS: In the sera of 34 patients with squamous cell carcinoma of the head and neck, the concentration of cysteine proteinase inhibitor cystatin C was determined using ELISA. The serum samples were collected at diagnosis (group A) and 7 to 407 days (median, 59 days) after the therapy (group B). The sera of 30 healthy blood donors served as controls (group C). RESULTS: A significant increase in the median concentration of cystatin C was found in the patients' sera (group A: 573 ng/ml, P<0.0001; group B: 551 ng/ml, P<0.0001) compared to control group C (320 ng/ml), whereas no difference was observed between groups A and B (P>0.05). Cystatin C concentrations in the sera of group A correlated with the site of primary tumor (P=0.035), being higher in the patients with non-laryngeal tumors (658 ng/ml) than in those with larynx primaries (529 ng/ml). There was a significant trend (RS=-0.535, P=0.049) towards lower cystatin C concentrations with an increasing time delay in post-treatment serum sampling (group B), which was observed in the patients with no relapse of the disease and a sampling later than 45 days after the completion of therapy. CONCLUSIONS: These results add to the knowledge of the role of cystatin C in invasive behavior of squamous cell carcinoma of the head and neck, and suggest its potential role as a tumor marker in this particular type of cancer.


Assuntos
Cistatinas/sangue , Neoplasias de Cabeça e Pescoço/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Cistatina C , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/diagnóstico , Recidiva
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