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1.
J Control Release ; 369: 668-683, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548064

RESUMO

Local and long-lasting administration of potent chemotherapeutics is a promising therapeutic intervention to increase the efficiency of chemotherapy of hard-to-treat tumors such as the most lethal brain tumors, glioblastomas (GBM). However, despite high toxicity for GBM cells, potent chemotherapeutics such as gemcitabine (Gem) cannot be widely implemented as they do not efficiently cross the blood brain barrier (BBB). As an alternative method for continuous administration of Gem, we here operate freestanding iontronic pumps - "GemIPs" - equipped with a custom-synthesized ion exchange membrane (IEM) to treat a GBM tumor in an avian embryonic in vivo system. We compare GemIP treatment effects with a topical metronomic treatment and observe that a remarkable growth inhibition was only achieved with steady dosing via GemIPs. Daily topical drug administration (at the maximum dosage that was not lethal for the embryonic host organism) did not decrease tumor sizes, while both treatment regimes caused S-phase cell cycle arrest and apoptosis. We hypothesize that the pharmacodynamic effects generate different intratumoral drug concentration profiles for each technique, which causes this difference in outcome. We created a digital model of the experiment, which proposes a fast decay in the local drug concentration for the topical daily treatment, but a long-lasting high local concentration of Gem close to the tumor area with GemIPs. Continuous chemotherapy with iontronic devices opens new possibilities in cancer treatment: the long-lasting and highly local dosing of clinically available, potent chemotherapeutics to greatly enhance treatment efficiency without systemic side-effects. SIGNIFICANCE STATEMENT: Iontronic pumps (GemIPs) provide continuous and localized administration of the chemotherapeutic gemcitabine (Gem) for treating glioblastoma in vivo. By generating high and constant drug concentrations near the vascularized growing tumor, GemIPs offer an efficient and less harmful alternative to systemic administration. Continuous GemIP dosing resulted in remarkable growth inhibition, superior to daily topical Gem application at higher doses. Our digital modelling shows the advantages of iontronic chemotherapy in overcoming limitations of burst release and transient concentration profiles, and providing precise control over dosing profiles and local distribution. This technology holds promise for future implants, could revolutionize treatment strategies, and offers a new platform for studying the influence of timing and dosing dependencies of already-established drugs in the fight against hard-to-treat tumors.


Assuntos
Apoptose , Neoplasias Encefálicas , Desoxicitidina , Gencitabina , Glioblastoma , Animais , Desoxicitidina/análogos & derivados , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Embrião de Galinha , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Administração Metronômica
2.
J Neurosci Methods ; 393: 109893, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37217139

RESUMO

BACKGROUND: Orthotopic xenograft studies promote the development of targeted/personalized therapies to improve the still poor life expectancy of glioblastoma patients. NEW METHOD: We implemented an atraumatic access to glioblastoma with cerebral Open Flow Microperfusion (cOFM) by implantation of xenograft cells in rat brain with intact blood brain barrier (BBB) and subsequent development of a xenograft glioblastoma at the interface between the cOFM probe and surrounding brain tissue. Human glioma U87MG cells were implanted at a well-defined position into immunodeficient Rowett nude rat´s brain via cOFM (cOFM group) and syringe (control group). Characteristics of the mature tumors from both groups were assessed. RESULTS: For the first time xenograft cells were successfully introduced into rat brain with intact BBB using cOFM, and the tumor tissue developing around the cOFM probe was unaffected by the presence of the probe. Thereby an atraumatic access to the tumor was created. The success rate of glioblastoma development in the cOFM group was high (>70%). The mature cOFM-induced tumors (20-23 days after cell-implantation) resembled the syringe-induced ones and showed typical features of human glioblastoma. COMPARISON WITH EXISTING METHOD: Examining xenograft tumor microenvironment with currently available methods inevitably causes trauma that could affect the reliability of obtained data. CONCLUSION: This novel atraumatic access to human glioblastoma in rat brain provides the possibility to collect interstitial fluid from functional tumor tissue in vivo without trauma generation. Thereby, reliable data can be generated promoting drug research, biomarker identification, and enabling investigation of the BBB of an intact tumor.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Humanos , Ratos , Glioblastoma/patologia , Xenoenxertos , Reprodutibilidade dos Testes , Encéfalo/patologia , Barreira Hematoencefálica , Modelos Animais de Doenças , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Microambiente Tumoral
3.
Viruses ; 15(4)2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37112888

RESUMO

BACKGROUND: There is an urgent need to better understand the mechanisms underlying acute and long-term neurological symptoms after COVID-19. Neuropathological studies can contribute to a better understanding of some of these mechanisms. METHODS: We conducted a detailed postmortem neuropathological analysis of 32 patients who died due to COVID-19 during 2020 and 2021 in Austria. RESULTS: All cases showed diffuse white matter damage with a diffuse microglial activation of a variable severity, including one case of hemorrhagic leukoencephalopathy. Some cases revealed mild inflammatory changes, including olfactory neuritis (25%), nodular brainstem encephalitis (31%), and cranial nerve neuritis (6%), which were similar to those observed in non-COVID-19 severely ill patients. One previously immunosuppressed patient developed acute herpes simplex encephalitis. Acute vascular pathologies (acute infarcts 22%, vascular thrombosis 12%, diffuse hypoxic-ischemic brain damage 40%) and pre-existing small vessel diseases (34%) were frequent findings. Moreover, silent neurodegenerative pathologies in elderly persons were common (AD neuropathologic changes 32%, age-related neuronal and glial tau pathologies 22%, Lewy bodies 9%, argyrophilic grain disease 12.5%, TDP43 pathology 6%). CONCLUSIONS: Our results support some previous neuropathological findings of apparently multifactorial and most likely indirect brain damage in the context of SARS-CoV-2 infection rather than virus-specific damage, and they are in line with the recent experimental data on SARS-CoV-2-related diffuse white matter damage, microglial activation, and cytokine release.


Assuntos
COVID-19 , Disfunção Cognitiva , Doenças do Sistema Nervoso , Neurite (Inflamação) , Substância Branca , Humanos , Idoso , COVID-19/complicações , SARS-CoV-2 , Substância Branca/patologia , Cobertura de Condição Pré-Existente , Doenças do Sistema Nervoso/patologia , Disfunção Cognitiva/etiologia
4.
Cardiovasc Intervent Radiol ; 45(6): 879-883, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35476090

RESUMO

Due to the risk of mobilizing plaque fragments, transfemoral TEVAR is a potentially dangerous procedure in patients with a coral reef aorta. We describe a practical method for transfemoral TEVAR in a patient with a degenerative thoracic aneurysm and a coral reef aorta. After placing a filter catheter in the abdominal aorta via a contralateral percutaneous femoral access, a working channel through the distal thoracic aorta was created with a balloon-expandable stent graft in the coral reef segment. Thereafter, transfemoral TEVAR could be performed successfully, without any complications. The additional use of a percutaneously placed filter catheter potentially allows reduction of peripheral embolism and hence may prevent patients from more invasive treatment.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Aorta , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Catéteres , Recifes de Corais , Procedimentos Endovasculares/métodos , Humanos , Estudos Retrospectivos , Stents , Resultado do Tratamento
5.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769194

RESUMO

Osteosarcoma (OS) is the most common type of bone tumor, and has limited therapy options. 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) has striking anti-tumor effects in various tumors. Here, we investigated molecular mechanisms that mediate anti-tumor effects of 15d-PGJ2 in different OS cell lines. Human U2-OS and Saos-2 cells were treated with 15d-PGJ2 and cell survival was measured by MTT assay. Cell proliferation and motility were investigated by scratch assay, the tumorigenic capacity by colony forming assay. Intracellular ROS was estimated by H2DCFDA. Activation of MAPKs and cytoprotective proteins was detected by immunoblotting. Apoptosis was detected by immunoblotting and Annexin V/PI staining. The ex ovo CAM model was used to study growth capability of grafted 15d-PGJ2-treated OS cells, followed by immunohistochemistry with hematoxylin/eosin and Ki-67. 15d-PGJ2 substantially decreased cell viability, colony formation and wound closure capability of OS cells. Non-malignant human osteoblast was less affected by 15d-PGJ2. 15d-PGJ2 induced rapid intracellular ROS production and time-dependent activation of MAPKs (pERK1/2, pJNK and pp38). Tempol efficiently inhibited 15d-PGJ2-induced ERK1/2 activation, while N-acetylcystein and pyrrolidine dithiocarbamate were less effective. Early but weak activation of cytoprotective proteins was overrun by induction of apoptosis. A structural analogue, 9,10-dihydro-15d-PGJ2, did not show toxic effects in OS cells. In the CAM model, we grafted OS tumors with U2-OS, Saos-2 and MG-63 cells. 15d-PGJ2 treatment resulted in significant growth inhibition, diminished tumor tissue density, and reduced tumor cell proliferation for all cell lines. Our in vitro and CAM data suggest 15d-PGJ2 as a promising natural compound to interfere with OS tumor growth.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Prostaglandina D2/análogos & derivados , Animais , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Galinhas , Ativação Enzimática/efeitos dos fármacos , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Osteossarcoma/metabolismo , Prostaglandina D2/farmacologia , Espécies Reativas de Oxigênio/metabolismo
6.
Adv Mater Technol ; 6(5): 2001302, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34195355

RESUMO

Successful treatment of glioblastoma multiforme (GBM), the most lethal tumor of the brain, is presently hampered by (i) the limits of safe surgical resection and (ii) "shielding" of residual tumor cells from promising chemotherapeutic drugs such as Gemcitabine (Gem) by the blood brain barrier (BBB). Here, the vastly greater GBM cell-killing potency of Gem compared to the gold standard temozolomide is confirmed, moreover, it shows neuronal cells to be at least 104-fold less sensitive to Gem than GBM cells. The study also demonstrates the potential of an electronically-driven organic ion pump ("GemIP") to achieve controlled, targeted Gem delivery to GBM cells. Thus, GemIP-mediated Gem delivery is confirmed to be temporally and electrically controllable with pmol min-1 precision and electric addressing is linked to the efficient killing of GBM cell monolayers. Most strikingly, GemIP-mediated GEM delivery leads to the overt disintegration of targeted GBM tumor spheroids. Electrically-driven chemotherapy, here exemplified, has the potential to radically improve the efficacy of GBM adjuvant chemotherapy by enabling exquisitely-targeted and controllable delivery of drugs irrespective of whether these can cross the BBB.

7.
Cancers (Basel) ; 13(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807050

RESUMO

Glioblastoma (GBM) is an utterly devastating cerebral neoplasm and current therapies only marginally improve patients' overall survival (OS). The PI3K/AKT/mTOR pathway participates in gliomagenesis through regulation of cell growth and proliferation. Since it is an upstream regulator of the rate-limiting translation initiation step of protein synthesis, controlled by eukaryotic initiation factors (eIFs), we aimed for a profound basic characterization of 17 eIFs to identify potential novel therapeutic targets for gliomas. Therefore, we retrospectively analyzed expressions of mTOR-related proteins and eIFs in human astrocytoma samples (WHO grades I-IV) and compared them to non-neoplastic cortical control brain tissue (CCBT) using immunoblot analyses and immunohistochemistry. We examined mRNA expression using qRT-PCR and additionally performed in silico analyses to observe the influence of eIFs on patients' survival. Protein and mRNA expressions of eIF3B, eIF3I, eIF4A1, eIF4H, eIF5 and eIF6 were significantly increased in high grade gliomas compared to CCBT and partially in low grade gliomas. However, short OS was only associated with high eIF3I gene expression in low grade gliomas, but not in GBM. In GBM, high eIF4H gene expression significantly correlated with shorter patient survival. In conclusion, we identified eIF3I and eIF4H as the most promising targets for future therapy for glioma patients.

8.
Front Neurol ; 11: 31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117004

RESUMO

Anti-myelin oligodendrocyte glycoprotein (MOG) antibodies (MOG-Abs) are commonly associated with clinical presentations as acute disseminated encephalomyelitis (ADEM) in both adults and children and anti-aquaporin 4 antibody-seronegative neuromyelitis optica spectrum disorder (NMOSD) and related syndromes such as optic neuritis, myelitis, and brainstem encephalitis. Most often, the presence of MOG-Abs is associated with a more benign clinical course and a good response to steroids. Here, we present a case report of a previously healthy 52-year-old female patient with fulminant demyelinating encephalitis, leading to death within a week after the first presenting symptoms from a massive brain edema irresponsive to high-dose intravenous steroids as well as osmotic therapy. The final diagnosis was only made postmortem after serum anti-MOG-Abs results were available. Histopathological analysis of the brain revealed extensive, predominantly cortical demyelinating lesions in the frontal, temporal, and parietal lobes with intracortical, leukocortical, and subpial plaques, associated with pronounced perivenous deposition of activated complement complex as well as features of acute MS characterized by destructive lesions.

10.
Sci Rep ; 9(1): 6183, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30971716

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

11.
Histopathology ; 75(1): 118-127, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30861166

RESUMO

AIMS: Because the hedgehog signalling pathway plays a major role in many types of cancer and can nowadays be targeted by specific compounds, we aimed to investigate the role of this pathway in squamous cell carcinoma of the head and neck. METHODS AND RESULTS: Ninety-eight treatment-naive head and neck cancer specimens were immunohistologically stained for SMO, GLI-1, p53 and p16 expression and correlated with clinicopathological factors. Immunoreactivity for SMO and GLI-1 was found in 20 (20.4%) and 52 (53.1%) cases of tumours, respectively. SMO expression correlated with GLI-1 expression (ρ = 0.258, P = 0.010) in univariate and multivariate analysis (P = 0.007, t = 2.81). In univariate analysis, high SMO expression was associated with shorter overall survival (HR = 0.56; 95% CI = 0.32-0.98; P = 0.044) and disease-free survival (HR = 0.53; 95% CI = 0.30-0.95; P = 0.034). In multivariate cox regression analysis SMO expression showed a trend towards an independent predictor for shorter overall survival (HR = 0.57; 95% CI = 0.30-1.05; P = 0.072) and disease-free survival (HR = 0.53; 95% CI = 0.28-1.02; P = 0.056). In head and neck cancer patients with low tumour p16 expression, SMO expression was an independent factor for overall survival (HR = 0.49; 95% CI = 0.24-0.98; P = 0.043) and disease-free survival (HR = 0.45; 95% CI = 0.22-0.96; P = 0.037). CONCLUSION: Although it needs to be confirmed in larger cohorts, our results suggest that targeting SMO might be a potentially therapeutic option in patients with head and neck cancer. In line, molecular pathological analyses including mutation analysis in the hedgehog pathway might point to additional therapeutic leads.


Assuntos
Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Receptor Smoothened/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Biomarcadores Tumorais/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Feminino , Proteínas Hedgehog/metabolismo , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Prognóstico , Estudos Retrospectivos , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
12.
J Invest Dermatol ; 139(4): 807-817, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30399362

RESUMO

The majority of Merkel cell carcinoma, a highly aggressive neuroendocrine cancer of the skin, is associated with Merkel cell polyomavirus infection. Polyomavirus binding, internalization, and infection are mediated by glycosphingolipids. Besides receptor function, bioactive sphingolipids are increasingly recognized as potent regulators of several hallmarks of cancer. Merkel cell polyomavirus+ and Merkel cell polyomavirus- cells express serine palmitoyl transferase subunits and sphingosine kinase (SK) 1/2 mRNA. Induced expression of Merkel cell polyomavirus-large tumor antigen in human lung fibroblasts resulted in upregulation of SPTLC1-3 and SK 1/2 expression. Therefore, we exploited pharmacological inhibition of sphingolipid metabolism as an option to interfere with proliferation of Merkel cell polyomavirus+ Merkel cell carcinoma cell lines. We used myriocin (a serine palmitoyl transferase antagonist) and two SK inhibitors (SKI-II and ABC294640). In MKL-1 and WaGa cells myriocin decreased cellular ceramide, sphingomyelin, and sphingosine-1-phosphate content. SKI-II increased ceramide species but decreased sphingomyelin and sphingosine-1-phosphate concentrations. Aberrant sphingolipid homeostasis was associated with reduced cell viability, increased necrosis, procaspase-3 and PARP processing, caspase-3 activity, and decreased AKTS473 phosphorylation. Myriocin and SKI-II decreased tumor size and Ki-67 staining of xenografted MKL-1 and WaGa tumors on the chorioallantoic membrane. Our data suggest that pharmacological inhibition of sphingolipid synthesis could represent a potential therapeutic approach in Merkel cell carcinoma.


Assuntos
Carcinoma de Célula de Merkel/tratamento farmacológico , Ácidos Graxos Monoinsaturados/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Infecções por Polyomavirus/tratamento farmacológico , Serina C-Palmitoiltransferase/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Infecções Tumorais por Vírus/tratamento farmacológico , Carcinoma de Célula de Merkel/metabolismo , Carcinoma de Célula de Merkel/patologia , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , Poliomavírus das Células de Merkel/imunologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Infecções por Polyomavirus/metabolismo , Infecções por Polyomavirus/patologia , RNA Neoplásico/genética , Serina C-Palmitoiltransferase/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Infecções Tumorais por Vírus/metabolismo , Infecções Tumorais por Vírus/patologia
13.
Eur J Cancer ; 101: 165-180, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30077122

RESUMO

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. Dysregulation of protein synthesis plays a major role in carcinogenesis, a process regulated at multiple levels, including translation of mRNA into proteins. Ribosome assembly requires correct association of ribosome subunits, which is ensured by eukaryotic translation initiation factors (eIFs). eIFs have become targets in cancer therapy studies, and promising data on eIF6 in various cancer entities have been reported. Therefore, we hypothesised that eIF6 represents a crossroad for pulmonary carcinogenesis. High levels of eIF6 are associated with shorter patient overall survival in adenocarcinoma (ADC), but not in squamous cell carcinoma (SQC) of the lung. We demonstrate significantly higher protein expression of eIF6 in ADC and SQC than in healthy lung tissue based on immunohistochemical data from tissue microarrays (TMAs) and on fresh frozen lung tissue. Depletion of eIF6 in ADC and SQC lung cancer cell lines inhibited cell proliferation and induced apoptosis. Knockdown of eIF6 led to pre-rRNA processing and ribosomal 60S maturation defects. Our data indicate that eIF6 is upregulated in NSCLC, suggesting an important contribution of eIF6 to the development and progression of NSCLC and a potential for new treatment strategies against NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fatores de Iniciação em Eucariotos/biossíntese , Neoplasias Pulmonares/metabolismo , Células A549 , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Progressão da Doença , Fatores de Iniciação em Eucariotos/genética , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Interferência de RNA
14.
J Am Coll Cardiol ; 71(14): 1540-1549, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29622161

RESUMO

BACKGROUND: Cardiac troponins are often elevated in patients with skeletal muscle disease who have no evidence of cardiac disease. OBJECTIVES: The goal of this study was to characterize cardiac troponin concentrations in patients with myopathies and derive insights regarding the source of elevated troponin T measurements. METHODS: Cardiac troponin T (cTnT) and cardiac troponin I (cTnI) concentrations were determined by using high sensitivity assays in 74 patients with hereditary and acquired skeletal myopathies. Patients underwent comprehensive cardiac evaluation, including 12-lead electrocardiogram, 24-h electrocardiogram, cardiac magnetic resonance imaging, and coronary artery computed tomography. cTnT and cTnI protein expression was determined in skeletal muscle samples of 9 patients and in control tissues derived from autopsy using antibodies that are used in commercial assays. Relevant Western blot bands were subjected to liquid chromatography tandem mass spectrometry for protein identification. RESULTS: Levels of cTnT (median: 24 ng/l; interquartile range: 11 to 54 ng/l) were elevated (>14 ng/l) in 68.9% of patients; cTnI was elevated (>26 ng/l) in 4.1% of patients. Serum cTnT levels significantly correlated with creatine kinase and myoglobin (r = 0.679 and 0.786, respectively; both p < 0.001). Based on cTnT serial testing, 30.1% would have fulfilled current rule-in criteria for myocardial infarction. Noncoronary cardiac disease was present in 23%. Using cTnT antibodies, positive bands were found in both diseased and healthy skeletal muscle at molecular weights approximately 5 kDa below cTnT. Liquid chromatography tandem mass spectrometry identified the presence of skeletal troponin T isoforms in these bands. CONCLUSIONS: Measured cTnT concentrations were chronically elevated in the majority of patients with skeletal myopathies, whereas cTnI elevation was rare. Our data indicate that cross-reaction of the cTnT immunoassay with skeletal muscle troponin isoforms was the likely cause.


Assuntos
Músculo Esquelético/metabolismo , Doenças Musculares/sangue , Miocárdio/metabolismo , Troponina T/sangue , Adulto , Biomarcadores/sangue , Western Blotting , Eletrocardiografia , Feminino , Humanos , Imunoensaio , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Doenças Musculares/diagnóstico , Tomografia Computadorizada por Raios X
15.
Sci Rep ; 8(1): 1132, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29348570

RESUMO

Continuous subcutaneous insulin infusion (CSII) catheters are considered the weak link of insulin pump therapy. Wear-time considerably varies between patients and the choice of catheter material is based on personal preferences rather than scientific facts. Therefore, we systematically assessed and quantified the inflammatory tissue response to steel versus Teflon CSII catheters over a maximum wear-time of 7 days in swine. Tissue surrounding catheters was analysed using histopathology and quantitative real-time PCR. The area of inflammation increased significantly over time independent of material which was confirmed by an increase in CD68 expression and an increase in mononuclear and neutrophil cell infiltrate around the catheters. We observed substantially higher fibrin deposition (p < 0.05) around steel on day 4 of wear-time. IL-6 gene expression increased within 24 hours after insertion, returned to normal levels around Teflon (p < 0.05) but remained high around steel (p < 0.05). IL-10 and TGF-ß levels did not resolve over time, indicating impaired wound healing. In conclusion, there was a major temporal effect in the acute inflammatory response to CSII catheters but we found little difference between materials. This study setup presents a robust tool for the systematic analysis of the tissue response to CSII catheters.


Assuntos
Catéteres/efeitos adversos , Inflamação/etiologia , Sistemas de Infusão de Insulina/efeitos adversos , Politetrafluoretileno , Aço , Animais , Biomarcadores , Biópsia , Feminino , Imuno-Histoquímica , Inflamação/patologia , Mediadores da Inflamação , Masculino , Suínos
16.
Neural Comput Appl ; 28(6): 1277-1292, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28706349

RESUMO

The main principle of diagnostic pathology is the reliable interpretation of individual cells in context of the tissue architecture. Especially a confident examination of bone marrow specimen is dependent on a valid classification of myeloid cells. In this work, we propose a novel rotation-invariant learning scheme for multi-class echo state networks (ESNs), which achieves very high performance in automated bone marrow cell classification. Based on representing static images as temporal sequence of rotations, we show how ESNs robustly recognize cells of arbitrary rotations by taking advantage of their short-term memory capacity. The performance of our approach is compared to a classification random forest that learns rotation-invariance in a conventional way by exhaustively training on multiple rotations of individual samples. The methods were evaluated on a human bone marrow image database consisting of granulopoietic and erythropoietic cells in different maturation stages. Our ESN approach to cell classification does not rely on segmentation of cells or manual feature extraction and can therefore directly be applied to image data.

17.
J Neuropathol Exp Neurol ; 76(1): 16-26, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040794

RESUMO

Malignant astrocytoma remains incurable and rapidly fatal despite multimodal therapy. In particular, accelerated tumor cell heterogeneity often overcomes therapeutic effects of molecular protein targeting. This study aimed at identifying a gene with therapeutic potential that was consistently downregulated with astrocytoma progression. Analysis of the "Rembrandt" gene expression data revealed Wnt inhibitory factor 1 (WIF1) gene as the most promising candidate with tumor suppressor function. Consequently, 288 randomly selected tissue regions of astrocytoma specimens were investigated immunohistochemically with the aid of image analysis. This in situ approach identified tumor areas with numerous single cells strongly expressing Wif-1. In diffuse and anaplastic astrocytoma, the proliferation index was independent of the generally weak Wif-1 expression in tumor cells but was significantly correlated with the density of Wif-1-expressing single cells, subsequently characterized as native and non-neoplastic oligodendrocytes. Because these cells may contribute to inhibition of tumor cell proliferation by paracrine signaling, the endogenous protein Wif-1 may represent a promising therapeutic agent with expected minimal side effects. Moreover, we suggest that immunohistochemistry for Wif might be useful for discriminating between astrocytic tumors and reactive changes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Oligodendroglia/metabolismo , Oligodendroglioma/metabolismo , Proteínas Repressoras/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/genética , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proliferação de Células/fisiologia , Humanos , Oligodendroglia/patologia , Oligodendroglioma/genética , Oligodendroglioma/patologia , Distribuição Aleatória , Proteínas Repressoras/genética
18.
Ann Thorac Surg ; 102(4): e309-11, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27645969

RESUMO

Until now, to our knowledge no case of bioprosthetic valvular thrombosis after implantation of the sutureless Sorin Perceval valve has been reported. Although sutureless aortic valve replacement has become a powerful tool in our daily practice, recent guidelines from the European Society of Cardiology, the European Association for Cardio-Thoracic Surgery, the American College of Cardiology, and the American Heart Association do not give specific recommendations on postoperative anticoagulation therapy. We report the first case of valve dysfunction resulting from thrombosis 12 months after implantation with a possible link to postoperative cortisole therapy.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/fisiopatologia , Bioprótese , Implante de Prótese de Valva Cardíaca/efeitos adversos , Trombose/diagnóstico por imagem , Idoso , Estenose da Valva Aórtica/diagnóstico por imagem , Remoção de Dispositivo/métodos , Ecocardiografia Doppler/métodos , Feminino , Seguimentos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/efeitos adversos , Cuidados Pós-Operatórios/métodos , Desenho de Prótese , Falha de Prótese , Reoperação/métodos , Suturas , Trombose/etiologia , Resultado do Tratamento
19.
PLoS One ; 11(8): e0160735, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27505420

RESUMO

The human heart has a heterogeneous structure, which is characterized by different cell types and their spatial configurations. The physical structure, especially the fibre orientation and the interstitial fibrosis, determines the electrical excitation and in further consequence the contractility in macroscopic as well as in microscopic areas. Modern image processing methods and parameters could be used to describe the image content and image texture. In most cases the description of the texture is not satisfying because the fibre orientation, detected with common algorithms, is biased by elements such as fibrocytes or endothelial nuclei. The goal of this work is to figure out if cardiac tissue can be analysed and classified on a microscopic level by automated image processing methods with a focus on an accurate detection of the fibre orientation. Quantitative parameters for identification of textures of different complexity or pathological attributes inside the heart were determined. The focus was set on the detection of the fibre orientation, which was calculated on the basis of the cardiomyocytes' nuclei. It turned out that the orientation of these nuclei corresponded with a high precision to the fibre orientation in the image plane. Additionally, these nuclei also indicated very well the inclination of the fibre.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Miocárdio/citologia , Algoritmos , Animais , Automação , Miócitos Cardíacos/citologia , Coelhos
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