Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Clin Cancer Res ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814263

RESUMO

PURPOSE: The ability to identify residual tumor tissues in patients with locally advanced esophageal cancer (EC) following neoadjuvant chemoradiotherapy (nCRT) is essential for monitoring the treatment response. Using the fluorescent tracer bevacizumab-800CW, we evaluated whether ultrasound-guided quantitative fluorescent molecular endoscopy (US-qFME), which combines quantitative fluorescence molecular endoscopy (qFME) with ultrasound-guided needle biopsy/single-fiber fluorescence (USNB/SFF), can be used to identify residual tumor tissues in patients following nCRT. PATIENTS AND METHODS: Eighteen patients received an additional endoscopy procedure the day before surgery. qFME was performed at the primary tumor site (PTS) and in healthy tissue to first establish the optimal tracer dose. USNB/SFF was then used to measure intrinsic fluorescence in the deeper PTS layers and in lymph nodes (LN) suspected for metastasis. Finally, the intrinsic fluorescence and the tissue optical properties, the absorption and the reduced scattering coefficient, were combined into a new parameter: omega. RESULTS: First, a dose of 25 mg bevacizumab-800CW allowed for clear differentiation between the PTS and healthy tissue, with a target-to-background ratio (TBR) of 2.98 (IQR: 1.86-3.03). Moreover, we found a clear difference between both the deeper esophageal PTS layers and suspected LN compared to healthy tissues, with TBR values of 2.18 and 2.17, respectively. Finally, our new parameter, omega, further improved the ability to differentiate between the PTS and healthy tissue. CONCLUSIONS: Combining bevacizumab-800CW with US-qFME may serve as a viable strategy for monitoring the response to nCRT in EC and may help stratify patients with respect to active surveillance versus surgery.

2.
Diagnostics (Basel) ; 13(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37174982

RESUMO

(1) Introduction: Near-infrared fluorescence (NIRF) combined with tumour-targeted tracers, such as bevacizumab-800CW, could aid surgical decision-making. This study explored the use of IRDye800CW, conjugated to bevacizumab, with four commercially available NIRF laparoscopes optimised for indocyanine green (ICG). (2) Methods: A (lymph node) phantom was made from a calibration device for NIRF and tissue-mimicking material. Serial dilutions of bevacizumab-800CW were made and ICG functioned as a reference. System settings, working distance, and thickness of tissue-mimicking material were varied to assess visibility of the fluorescence signal and tissue penetration. Tests were performed with four laparoscopes: VISERA ELITE II, Olympus; IMAGE1 S™ 4U Rubina, KARL STORZ; ENDOCAM Logic 4K platform, Richard Wolf; da Vinci Xi, Intuitive Surgical. (3) Results: The lowest visible bevacizumab-800CW concentration ranged between 13-850 nM (8-512 times diluted stock solution) for all laparoscopes, but the tracer was not visible through 0.8 cm of tissue in all systems. In contrast, ICG was still visible at a concentration of 0.4 nM (16,384 times diluted) and through 1.6-2.4 cm of tissue. Visibility and tissue penetration generally improved with a reduced working distance and manually adjusted system settings. (4) Conclusion: Depending on the application, bevacizumab-800CW might be sufficiently visible with current laparoscopes, but optimisation would widen applicability of tumour-targeted IRDye800CW tracers.

3.
J Biomed Opt ; 27(7)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35393792

RESUMO

SIGNIFICANCE: The combination of reflectance and fluorescence spectroscopy allows the determination of tissue optical properties and the calculation of the intrinsic fluorescence in vivo. These parameters can discriminate between tissues and may allow the discrimination of malignant from benign tissue. While this approach has significant clinical potential, the lack of standardization and quality assessment prevents the upscaling of research. AIM: Investigate which factors influence device calibration and tissue optical property determination. Improve system quality assessment and allow upscaling of the clinical research using multidiameter single fiber reflectance/singe fiber fluorescence spectroscopy. APPROACH: Two studies, one phantom based on uniform calibrations and skin measurements and a clinical study including clinical calibrations. The first validates the effect of factors under identical conditions and the effect of calibration quality on the optical property determination of skin. The second shows the effect of different system configurations and the performance of the system and probe over an extended period. RESULTS: Phantom calibrations showed stability over a period of 20 weeks except for a 16-week-old intralipid phantom which showed a significant difference (at least p = 0.0032) for all five probes evaluated. For clinical calibrations, only the fiber tree had a significant influence (probe 4: p < 0.000001 and probe 5: p = 0.00038) on the calibration quality. Interestingly, no degradation of probe performance was detected over a period of 21 months despite the exposure to stress during clinical measurements. Calibration quality affected µs' and the power law scattering exponent, but the degree of the influence was different per fiber. CONCLUSIONS: Intralipid phantom quality and fiber tree performance are the main factors influencing the calibration quality. Probe and user performance did not show any effect, which makes the upscaling of research to multicenter trials easier. A high-quality assessment procedure should be implemented to track changes during clinical trials.


Assuntos
Calibragem , Imagens de Fantasmas , Padrões de Referência , Espectrometria de Fluorescência/métodos
4.
Rev Endocr Metab Disord ; 23(3): 647-657, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35344185

RESUMO

Differentiation of pituitary neuroendocrine tumor (PitNET) tissue from surrounding normal tissue during surgery is challenging. A number of fluorescent agents is available for visualization of tissue discrepancy, with the potential of improving total tumor resection. This review evaluates the availability, clinical and technical applicability of the various fluorescent agents within the field of pituitary surgery. According to PRISMA guidelines, a systematic review was performed to identify reports describing results of in vivo application of fluorescent agents. In this review, 15 publications were included. Sodium Fluorescein (FNa) was considered in two studies. The first study reported noticeable fluorescence in adenoma tissue, the second demonstrated the strongest fluorescence in non-functioning pituitary adenomas. 5-Aminolevulinic acid (5-ALA) was investigated in three studies. One study compared laser-based optical biopsy system (OBS) with photo-diagnostic filter (PD) and found that the OBS was able to detect all microadenomas, even when MRI was negative. The second study retrospectively analyzed twelve pituitary adenomas and found only one positive for fluorescence. The third investigated fifteen pituitary adenomas of which one displayed vague fluorescence. Indocyanine green (ICG) was researched in four studies with variable results. Second-Window ICG yielded no significant difference between functioning and non-functioning adenomas in one study, while a second study displayed 4 times higher fluorescence in tumor tissue than in normal tissue. In three studies, OTL38 showed potential in non-functioning pituitary adenomas. At present, evidence for fluorescent agents to benefit total resection of PitNETs is lacking. OTL38 can potentially serve as a selective fluorescent agent in non-functioning pituitary adenomas in the near future.


Assuntos
Adenoma , Tumores Neuroendócrinos , Neoplasias Hipofisárias , Adenoma/diagnóstico , Adenoma/patologia , Adenoma/cirurgia , Corantes Fluorescentes , Humanos , Verde de Indocianina , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/cirurgia , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos
5.
J Biomed Opt ; 27(7)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35170264

RESUMO

SIGNIFICANCE: Near-infrared fluorescence molecular endoscopy (NIR-FME) is an innovative technique allowing for in vivo visualization of molecular processes in hollow organs. Despite its potential for clinical translation, NIR-FME still faces challenges, for example, the lack of consensus in performing quality control and standardization of procedures and systems. This may hamper the clinical approval of the technology by authorities and its acceptance by endoscopists. Until now, several clinical trials using NIR-FME have been performed. However, most of these trials had different study designs, making comparison difficult. AIM: We describe the need for standardization in NIR-FME, provide a pathway for setting up a standardized clinical study, and describe future perspectives for NIR-FME. Body: Standardization is challenging due to many parameters. Invariable parameters refer to the hardware specifications. Variable parameters refer to movement or tissue optical properties. Phantoms can be of aid when defining the influence of these variables or when standardizing a procedure. CONCLUSION: There is a need for standardization in NIR-FME and hurdles still need to be overcome before a widespread clinical implementation of NIR-FME can be realized. When these hurdles are overcome, clinical outcomes can be compared and systems can be benchmarked, enabling clinical implementation.


Assuntos
Endoscopia Gastrointestinal , Fluorescência , Imagens de Fantasmas , Controle de Qualidade , Padrões de Referência
6.
Int J Med Sci ; 19(2): 205-212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35165506

RESUMO

This study aimed to determine the ability of single fiber reflectance (SFR) spectroscopy incorporated in endoscopic ultrasound fine needle biopsy (EUS-FNB) procedures in the pancreas to distinguish benign and malignant pancreatic tissue in patient with pancreatic masses suspected for malignancy. Methods: This study was designed as a prospective observational single center study and included consecutive adult patients, who were scheduled for EUS-FNB of a solid pancreatic mass suspected for pancreatic ductal adenocarcinoma (PDAC). In total, seven optical parameters, derived from the absorption acquired spectra, were analyzed: blood volume fraction (BVF), microvascular saturation, average vessel diameter, bilirubin concentration (BIL), Mie amplitude, Mie slope and Rayleigh amplitude. Results: Forty-five patients with a suspicious pancreatic lesion undergoing EUS-FNB were included, of which most of the patients (N=34) were ultimately diagnosed with PDAC. Finally, 27 out of 45 (60.0%) patients were used for the final analysis of the optical parameters. The median (IQR) BVF differed significantly in benign compared to malignant tissue (0.86 [0.30-2.03] and 4.49 [1.28-15.47]; p=0.046). Combining BVF and BIL to a new parameter (θ) improved the discrimination between PDAC and benign pancreatic tissue (p=0.026). The area under the curve of θ was 0.84, resulting in a 92.8%, 75.0%, 97.5%, 50.0% and 91.3% sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for detection of PDAC. Conclusion: Differentiation between PDAC and benign pancreatic tissue using SFR spectroscopy during EUS-FNB procedures is promising. Future work should focus on comparing the diagnostic performance combining SFR spectroscopy with EUS-FNB and EUS-FNB alone.


Assuntos
Detecção Precoce de Câncer/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Pancreáticas/diagnóstico , Análise Espectral/métodos , Idoso , Área Sob a Curva , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
7.
BMJ Open ; 11(10): e049109, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620658

RESUMO

INTRODUCTION: Achieving gross total resection and endocrine remission in pituitary neuroendocrine tumours (PitNET) can be challenging, especially in PitNETs with cavernous sinus (CS) invasion, defined as a Knosp grade of 3 or 4. A potential target to identify PitNET tissue is vascular endothelial growth factor A (VEGF-A), which expression is known to be significantly higher in PitNETs with CS invasion. METHODS AND ANALYSIS: The aim of this non-randomised, non-blinded, single centre, feasibility and dose-finding phase 1 trial is to determine the feasibility of intraoperative fluorescence imaging detection of PitNET tissue during endoscopic transsphenoidal surgery using the VEGF-A targeting optical agent bevacizumab-800CW (4, 5, 10 or 25 mg). Nine to fifteen patients with a PitNET with a Knosp grade of 3 or 4 will be included. Secondary objectives are: (1) To identify the optimal tracer dose for imaging of PitNET tissue during transsphenoidal surgery for further development in a phase 2 fluorescence molecular endoscopy trial. (2) To quantify fluorescence intensity in vivo and ex vivo with multidiameter single-fibre reflectance, single-fibre fluorescence (MDSFR/SFF) spectroscopy. (3) To correlate and validate both the in vivo and ex vivo measured fluorescence signals with histopathological analysis and immunohistochemical staining. (4) To assess the (sub)cellular location of bevacizumab-800CW by ex vivo fluorescence microscopy. Intraoperative, three imaging moments are defined to detect the fluorescent signal. The tumour-to-background ratios are defined by intraoperative fluorescence in vivo measurements including MDSFR/SFF spectroscopy data and by ex vivo back-table fluorescence imaging. After inclusion of three patients in each dose group, an interim analysis will be performed to define the optimal dose. ETHICS AND DISSEMINATION: Approval was obtained from the Medical Ethics Review Board of the University Medical Centre Groningen. Results will be disseminated through national and international journals. The participants and relevant patient support groups will be informed about the results. TRIAL REGISTRATION NUMBER: NCT04212793.


Assuntos
Tumores Neuroendócrinos , Neoplasias Hipofisárias , Bevacizumab , Endoscopia , Estudos de Viabilidade , Humanos , Tumores Neuroendócrinos/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Fator A de Crescimento do Endotélio Vascular
8.
Mol Ther ; 29(8): 2441-2455, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-33895329

RESUMO

Mutations in USH2A are among the most common causes of syndromic and non-syndromic retinitis pigmentosa (RP). The two most recurrent mutations in USH2A, c.2299delG and c.2276G > T, both reside in exon 13. Skipping exon 13 from the USH2A transcript presents a potential treatment modality in which the resulting transcript is predicted to encode a slightly shortened usherin protein. Morpholino-induced skipping of ush2a exon 13 in zebrafish ush2armc1 mutants resulted in the production of usherinΔexon 13 protein and a completely restored retinal function. Antisense oligonucleotides were investigated for their potential to selectively induce human USH2A exon 13 skipping. Lead candidate QR-421a induced a concentration-dependent exon 13 skipping in induced pluripotent stem cell (iPSC)-derived photoreceptor precursors from an Usher syndrome patient homozygous for the c.2299delG mutation. Mouse surrogate mQR-421a reached the retinal outer nuclear layer after a single intravitreal injection and induced a detectable level of exon skipping until at least 6 months post-injection. In conclusion, QR-421a-induced exon skipping proves to be a highly promising treatment option for RP caused by mutations in USH2A exon 13.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Mutação , Oligonucleotídeos Antissenso/administração & dosagem , Retinose Pigmentar/tratamento farmacológico , Animais , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Éxons , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Modelos Moleculares , Oligonucleotídeos Antissenso/farmacologia , Retina/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Theranostics ; 10(12): 5357-5367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373217

RESUMO

Fluorescence molecular endoscopy (FME) is an emerging technique in the field of gastroenterology that holds potential to improve diagnosis and guide therapy, by serving as a 'red-flag' endoscopic imaging technique. Here, we investigated the safety, feasibility and optimal method of administration of EMI-137, targeting c-Met, during FME in Barrett's Esophagus (BE) and report several outcome parameters for early phase FME studies. Methods: FME was performed in 15 Barrett's neoplasia patients. EMI-137 was administered to three cohorts of five patients: 0.13 mg/kg intravenously (IV); 0.09 mg/kg IV or topically at a dose of 200 µg/cm BE (n=1) or 100 µg/cm BE (n=4). Fluorescence was visualized in vivo, quantified in vivo using multi-diameter single-fiber reflectance, single-fiber fluorescence (MDSFR/SFF) spectroscopy and correlated to histopathology and immunohistochemistry. EMI-137 localization was assessed using fluorescence microscopy. Results: FME using different IV and topical doses of EMI-137 appeared to be safe and correctly identified 16/18 lesions, although modest target-to-background ratios were observed (median range of 1.12-1.50). C-Met overexpression varied between lesions, while physiological expression in the stomach-type epithelium was observed. Microscopically, EMI-137 accumulated around the neoplastic cell membranes. We identified several outcome parameters important for the validation of EMI-137 for FME: 1) the optimal administration route; 2) optimal dose and safety; 3) in vivo FME contrast; 4) quantification of intrinsic fluorescence; 5) ex vivo correlation of fluorescence, histopathology and target expression; and 6) microscopic tracer distribution. Conclusions: C-Met targeted FME using EMI-137 may not be the ideal combination to improve BE surveillance endoscopies, however the identified outcome parameters may serve as a valuable guidance for designing and performing future early phase clinical FME studies, independent of which fluorescent tracer is investigated.


Assuntos
Esôfago de Barrett/metabolismo , Neoplasias Esofágicas/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Idoso , Biópsia/métodos , Neoplasias Esofágicas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-met/genética
10.
J Nucl Med ; 61(10): 1435-1441, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32198312

RESUMO

Fluorescence molecular endoscopy (FME) is an emerging technique that has the potential to improve the 22% colorectal polyp detection miss-rate. We determined the optimal dose-to-imaging interval and safety of FME using EMI-137, a c-Met-targeted fluorescent peptide, in a population at high risk for colorectal cancer. Methods: We performed in vivo FME and quantification of fluorescence by multidiameter single-fiber reflectance/single-fiber fluorescence spectroscopy in 15 patients with a dysplastic colorectal adenoma. EMI-137 was intravenously administered (0.13 mg/kg) at a 1-, 2- or 3-h dose-to-imaging interval (n = 3 patients per cohort). Two cohorts were expanded to 6 patients on the basis of target-to-background ratios. Fluorescence was correlated to histopathology and c-Met expression. EMI-137 binding specificity was assessed by fluorescence microscopy and in vitro experiments. Results: FME using EMI-137 appeared to be safe and well tolerated. All dose-to-imaging intervals showed significantly higher fluorescence in the colorectal lesions than in surrounding tissue, with a target-to-background ratio of 1.53, 1.66, and 1.74 for the 1-, 2-, and 3-h cohorts, respectively, and a mean intrinsic fluorescence of 0.035 vs. 0.023 mm-1 (P < 0.0003), 0.034 vs. 0.021 mm-1 (P < 0.0001), and 0.033 vs. 0.019 mm-1 (P < 0.0001), respectively. Fluorescence correlated with histopathology on a macroscopic and microscopic level, with significant c-Met overexpression in dysplastic mucosa. In vitro, a dose-dependent specific binding was confirmed. Conclusion: FME using EMI-137 appeared to be safe and feasible within a 1- to 3-h dose-to-imaging interval. No clinically significant differences were observed among the cohorts, although a 1-h dose-to-imaging interval was preferred from a clinical perspective. Future studies will investigate EMI-137 for improved colorectal polyp detection during screening colonoscopies.


Assuntos
Adenoma/diagnóstico por imagem , Pólipos do Colo/diagnóstico por imagem , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico por imagem , Proteínas Proto-Oncogênicas c-met/metabolismo , Espectrometria de Fluorescência/métodos , Idoso , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Feminino , Células HT29 , Humanos , Masculino , Pessoa de Meia-Idade
11.
Mol Ther Nucleic Acids ; 12: 730-740, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30114557

RESUMO

Leber congenital amaurosis type 10 (LCA10) is a severe inherited retinal dystrophy associated with mutations in CEP290. The deep intronic c.2991+1655A>G mutation in CEP290 is the most common mutation in LCA10 individuals and represents an ideal target for oligonucleotide therapeutics. Here, a panel of antisense oligonucleotides was designed to correct the splicing defect associated with the mutation and screened for efficacy and safety. This identified QR-110 as the best-performing molecule. QR-110 restored wild-type CEP290 mRNA and protein expression levels in CEP290 c.2991+1655A>G homozygous and compound heterozygous LCA10 primary fibroblasts. Furthermore, in homozygous three-dimensional iPSC-derived retinal organoids, QR-110 showed a dose-dependent restoration of mRNA and protein function, as measured by percentage and length of photoreceptor cilia, without off-target effects. Localization studies in wild-type mice and rabbits showed that QR-110 readily reached all retinal layers, with an estimated half-life of 58 days. It was well tolerated following intravitreal injection in monkeys. In conclusion, the pharmacodynamic, pharmacokinetic, and safety properties make QR-110 a promising candidate for treating LCA10, and clinical development is currently ongoing.

12.
Int J Cancer ; 142(2): 297-307, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28921546

RESUMO

Neuroblastoma is the most common extracranial solid tumor in childhood. The vast majority of metastatic (M) stage patients present with disseminated tumor cells (DTCs) in the bone marrow (BM) at diagnosis and relapse. Although these cells represent a major obstacle in the treatment of neuroblastoma patients, insights into their expression profile remained elusive. The present RNA-Seq study of stage 4/M primary tumors, enriched BM-derived diagnostic and relapse DTCs, as well as the corresponding BM-derived mononuclear cells (MNCs) from 53 patients revealed 322 differentially expressed genes in DTCs as compared to the tumors (q < 0.001, |log2 FC|>2). Particularly, the levels of transcripts encoded by mitochondrial DNA were elevated in DTCs, whereas, for example, genes involved in angiogenesis were downregulated. Furthermore, 224 genes were highly expressed in DTCs and only slightly, if at all, in MNCs (q < 8 × 10-75 log2 FC > 6). Interestingly, we found the transcriptome of relapse DTCs largely resembling those of diagnostic DTCs with only 113 differentially expressed genes under relaxed cut-offs (q < 0.01, |log2 FC|>0.5). Notably, relapse DTCs showed a positional enrichment of 31 downregulated genes on chromosome 19, including five tumor suppressor genes: SIRT6, BBC3/PUMA, STK11, CADM4 and GLTSCR2. This first RNA-Seq analysis of neuroblastoma DTCs revealed their unique expression profile in comparison to the tumors and MNCs, and less pronounced differences between diagnostic and relapse DTCs. The latter preferentially affected downregulation of genes encoded by chromosome 19. As these alterations might be associated with treatment failure and disease relapse, further functional studies on DTCs should be considered.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Medula Óssea/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Células Neoplásicas Circulantes/metabolismo , Neuroblastoma/genética , Transcriptoma , Biomarcadores Tumorais/sangue , Neoplasias da Medula Óssea/sangue , Neoplasias da Medula Óssea/secundário , Progressão da Doença , Humanos , Células Neoplásicas Circulantes/patologia , Neuroblastoma/sangue , Neuroblastoma/patologia , Prognóstico
13.
Sci Rep ; 6: 35200, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27731380

RESUMO

Spinocerebellar ataxia type-3 (SCA3) is a neurodegenerative disorder caused by a polyglutamine repeat expansion in the ataxin-3 protein. Cleavage of mutant ataxin-3 by proteolytic enzymes yields ataxin-3 fragments containing the polyglutamine stretch. These shorter ataxin-3 fragments are thought to be involved in SCA3 pathogenesis due to their increased cellular toxicity and their involvement in formation of the characteristic neuronal aggregates. As a strategy to prevent formation of toxic cleavage fragments, we investigated an antisense oligonucleotide-mediated modification of the ataxin-3 pre-mRNA through exon skipping of exon 8 and 9, resulting in the removal of a central 88 amino acid region of the ataxin-3 protein. This removed protein region contains several predicted cleavage sites and two ubiquitin-interacting motifs. In contrast to unmodified mutant ataxin-3, the internally truncated ataxin-3 protein did not give rise to potentially toxic cleavage fragments when incubated with caspases. In vitro experiments did not show cellular toxicity of the modified ataxin-3 protein. However, the modified protein was incapable of binding poly-ubiquitin chains, which may interfere with its normal deubiquitinating function. Low exon skipping efficiencies combined with reduction in important ataxin-3 protein functions suggest that skipping of exon 8 and 9 is not a viable therapeutic option for SCA3.


Assuntos
Ataxina-3/metabolismo , Proteínas Repressoras/metabolismo , Ataxina-3/química , Ataxina-3/genética , Sítios de Ligação/genética , Calpaína/metabolismo , Linhagem Celular , Quebras de DNA de Cadeia Dupla , Éxons/genética , Humanos , Doença de Machado-Joseph/genética , Doença de Machado-Joseph/metabolismo , Doença de Machado-Joseph/terapia , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Oligonucleotídeos Antissenso/genética , Poliubiquitina/metabolismo , Proteólise , Precursores de RNA/genética , Precursores de RNA/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética
14.
Cytokine ; 61(2): 645-55, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23299081

RESUMO

Interleukin-12 (IL-12), IL-23 and interferon-γ (IFN-γ) are pivotal cytokines acting in concert with tumor necrosis factor (TNF) and IL-1ß to shape type I immune responses against bacterial pathogens. Recently, several groups reported that type I immunity can be inhibited by IFN-α/ß. Here we show the extent of the inhibitory effects of IFN-α and IFN-ß on the responsiveness of human monocytes to Toll like receptor-ligands and IFN-γ. Both IFN-α and IFN-ß strongly reduced the production of IL-12p40, IL-1ß and TNF and the IFN-γ induced CD54 and CD64 expression. High IFN-γ concentrations could not counterbalance the inhibitions and IFN-α still inhibited monocytes 24h after stimulation in vitro as well as in vivo in patients undergoing IFN-α treatment. Next, we explored the mechanism of inhibition. We confirm that IFN-α/ß interferes with the IFN-γR1 expression, by studying the kinetics of IFN-γR1 downregulation. However, IFN-γR1 downregulation occurred only after two hours of IFN-α/ß stimulation and was transient, which cannot explain the IFN-γ unresponsiveness observed directly and late after IFN-α/ß stimulation. Additional experiments indeed indicate that other mechanisms are involved. IFN-α may interfere with IFN-γ-elicited phosphorylation of signal transducer and activator of transcription 1 (STAT1). IFN-α may also activate methyltransferases which in turn reduce, at least partly, the TNF and IL-1ß production and CD54 expression. IFN-α also induces the protein inhibitor of activated STAT1 (PIAS1). In conclusion, IFN-α and IFN-ß strongly inhibit the IFN-γ responsiveness and the production of type I cytokines of monocytes, probably via various mechanisms. Our findings indicate that IFN-α/ß play a significant role in the immunopathogenesis of bacterial infections, for example Mycobacterium tuberculosis infection.


Assuntos
Imunidade/efeitos dos fármacos , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Regulação para Baixo/efeitos dos fármacos , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interferon beta/biossíntese , Interferon gama/farmacologia , Subunidade p40 da Interleucina-12/biossíntese , Ligantes , Fosforilação/efeitos dos fármacos , Proteínas Inibidoras de STAT Ativados/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Receptores de IgG/metabolismo , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
15.
Brain Behav Immun ; 26(1): 13-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21801830

RESUMO

In addition to neuroendocrine changes PTSD pathophysiology may also involve dysfunction of the innate immune inflammatory system. PTSD patients have been found to exhibit increased concentrations of circulating inflammatory markers such as C-reactive protein and interleukin-6, suggesting dysfunction of the innate immune inflammatory system. However, few studies have investigated molecular signaling pathways known to critically regulate inflammation. Additionally, the relationship between inflammatory function and immune cell glucocorticoid sensitivity has not been extensively explored in PTSD. Nuclear factor-κB (NF-κB) pathway activity was examined in peripheral blood mononuclear cells obtained from 12 women with childhood abuse-related PTSD and 24 healthy controls (ages 19-48) using DNA-binding ELISA. Glucocorticoid sensitivity of monocytes in whole blood was measured as the concentration of dexamethasone needed to suppress in vitro lipopolysaccharide-induced tumor necrosis factor-alpha production by 50% (DEX IC(50)). Women with PTSD displayed increased NF-κB pathway activity compared to controls (t [34]=2.45, p=0.02) that was positively correlated with PTSD severity (determined by PTSD symptom severity scale) (r(s)=0.39, p=0.02). Increased NF-κB pathway activity was associated with increased whole blood monocyte DEX IC(50) (i.e. decreased sensitivity of monocytes to glucocorticoids) across all participants (r=0.66, p<0.001). These findings suggest that enhanced inflammatory system activity in participants with childhood abuse-related PTSD is observable at the level of NF-κB, and that in general decreased immune cell glucocorticoid sensitivity may contribute to increased NF-κB pathway activity. Enhanced inflammation may contribute to co-morbid somatic disease risk in persons with childhood abuse-related PTSD.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/psicologia , NF-kappa B/fisiologia , Vias Neurais/metabolismo , Sistema Nervoso Periférico/fisiologia , Transdução de Sinais/fisiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Criança , Depressão/psicologia , Feminino , Glucocorticoides/sangue , Humanos , Hidrocortisona/sangue , Pessoa de Meia-Idade , Monócitos/metabolismo , NF-kappa B/metabolismo , Sistema Nervoso Periférico/metabolismo , Escalas de Graduação Psiquiátrica , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto Jovem
16.
J Psychosom Obstet Gynaecol ; 30(4): 282-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19922402

RESUMO

OBJECTIVES: Chronic pelvic pain (CPP) is a frequent gynecological complaint. The pathophysiology of CPP is not fully understood. The aim of this study was to determine whether the presence of depressive symptoms is associated with hypothalamic-pituitary-adrenal (HPA) axis dysfunction in CPP. METHODS: We measured neuroendocrine responses to a standardized social stress test and to a standard adrenocorticotropin (ACTH)(1-24) stimulation test in 18 patients with CPP, stratified based on the presence of high versus low self-reported depressive symptoms, compared with 24 controls. RESULTS: Women with CPP and low depression exhibited enhanced ACTH responses to psychosocial stress compared with women with CPP and high depression, whereas there were no differences in cortisol responses. In the ACTH(1-24) stimulation test, CPP patients with high depression demonstrated enhanced cortisol responses. CONCLUSION: These results suggest a relationship between self-reported depression and reactivity of the HPA axis in patients with CPP.


Assuntos
Depressão/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Dor Pélvica/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Hormônio Adrenocorticotrópico , Análise de Variância , Doença Crônica , Depressão/complicações , Feminino , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Dor Pélvica/complicações , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Estresse Psicológico/fisiopatologia
17.
Psychosom Med ; 70(1): 65-72, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18158367

RESUMO

OBJECTIVE: Chronic pelvic pain (CPP) and fibromyalgia syndrome (FMS) have been associated with hypothalamic-pituitary-adrenal (HPA) axis alterations, i.e., mild hypocortisolism and enhanced feedback sensitivity. We tested the hypothesis of reduced cortisol release in response to a psychosocial stressor and pharmacological stimulation. Furthermore, glucocorticoid (GC) sensitivity was evaluated. METHODS: Plasma total and salivary-free cortisol concentrations were measured in response to a standardized social laboratory stressor, the Trier Social Stress Test, and to adrenocorticotropin (ACTH)(1-24) stimulation. In the Trier Social Stress Test, we additionally measured ACTH. GC sensitivity was measured by dexamethasone inhibition of lipopolysaccharide-induced interleukin-6 and tumor necrosis factor-alpha production in whole blood. RESULTS: There were no HPA axis alterations in women with CPP (N = 18) in these tests. Patients with FMS (N = 17) showed lower total cortisol release in response to the social stressor and exogenous ACTH, but normal free cortisol and ACTH levels compared with controls (N = 24). GC sensitivity was similar in all groups. CONCLUSIONS: Our results suggest normal HPA responses to stress and ACTH stimulation in patients with CPP but reduced adrenal reactivity in patients with FMS, namely in total cortisol release. Free cortisol on the other hand was unaltered, possibly reflecting an adaptation to reduced circulating total cortisol.


Assuntos
Fibromialgia/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Dor Pélvica/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Doença Crônica , Dexametasona/administração & dosagem , Feminino , Glucocorticoides/administração & dosagem , Humanos , Hidrocortisona/análise , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Pessoa de Meia-Idade , Saliva/química , Estresse Psicológico
18.
J Psychosom Res ; 62(1): 85-91, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17188125

RESUMO

OBJECTIVE: Fibromyalgia syndrome (FMS) has been associated with decreased cortisol secretion. Patients with posttraumatic stress disorder (PTSD) exhibit similar hypocortisolism in the context of increased negative feedback sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis. Because trauma and PTSD have been associated with fibromyalgia, we evaluated whether patients with fibromyalgia demonstrate increased HPA feedback sensitivity. METHOD: Baseline blood samples were obtained at 0800 h, and 0.5 mg of dexamethasone was administered to 15 female patients with FMS and 20 normal controls at 2300 h. Adrenocorticotropin (ACTH), cortisol, and dexamethasone levels were measured at 0800 h after dexamethasone intake. RESULTS: There were no group differences in mean ACTH or cortisol levels or in ACTH/cortisol ratio at baseline. After dexamethasone intake, patients with FMS exhibited more pronounced suppression of cortisol but not of ACTH, as well as increased ACTH/cortisol ratios compared with controls. Percent cortisol suppression was associated with pain and fatigue, while ACTH/cortisol ratio and dexamethasone availability were associated with stress and anxiety measures. CONCLUSION: Our results suggest increased sensitivity to glucocorticoid feedback, manifested at the adrenal level, in FMS.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Dexametasona , Fibromialgia/sangue , Hidrocortisona/sangue , Adulto , Ansiedade/sangue , Ansiedade/psicologia , Biorretroalimentação Psicológica/fisiologia , Depressão/sangue , Depressão/psicologia , Dexametasona/administração & dosagem , Relação Dose-Resposta a Droga , Fadiga/sangue , Fadiga/psicologia , Feminino , Fibromialgia/psicologia , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Pessoa de Meia-Idade , Dor/sangue , Dor/psicologia , Sistema Hipófise-Suprarrenal/fisiopatologia
19.
Tijdschr Gerontol Geriatr ; 35(3): 107-13, 2004 Jun.
Artigo em Holandês | MEDLINE | ID: mdl-15334785

RESUMO

In this study the Clock Drawing Test (CDT) is used in a geriatric department to search for dementia in a population with somatic disorders (N=236). The demented group (N=113) has significant lower scores on every item and on the total score of the scoring method, compared to the non-demented group (N=123). A factor analysis of the scoring method shows that the fourteen items can be grouped into the three groups "contour", "digits", and "hands". A logistic regression shows that "hands" is the most discriminating, although this effect is moderate (sensitivity 59.3%, specificity 75.6%). Considering however that the CDT, compared to other screening tasks, appeals to an unique combination of cognitive functions, including visual semantic memory, working memory, visuospatial skills, attention and executive functions, it can be concluded that this test can contribute to the diagnoses of dementia, besides the traditionally used instruments.


Assuntos
Demência/diagnóstico , Programas de Rastreamento/métodos , Testes Neuropsicológicos , Idoso , Idoso de 80 Anos ou mais , Demência/psicologia , Análise Fatorial , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Desempenho Psicomotor , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA