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1.
Mol Cell ; 83(4): 622-636.e10, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36657444

RESUMO

Despite extensive studies on the chromatin landscape of exhausted T cells, the transcriptional wiring underlying the heterogeneous functional and dysfunctional states of human tumor-infiltrating lymphocytes (TILs) is incompletely understood. Here, we identify gene-regulatory landscapes in a wide breadth of functional and dysfunctional CD8+ TIL states covering four cancer entities using single-cell chromatin profiling. We map enhancer-promoter interactions in human TILs by integrating single-cell chromatin accessibility with single-cell RNA-seq data from tumor-entity-matching samples and prioritize cell-state-specific genes by super-enhancer analysis. Besides revealing entity-specific chromatin remodeling in exhausted TILs, our analyses identify a common chromatin trajectory to TIL dysfunction and determine key enhancers, transcriptional regulators, and deregulated genes involved in this process. Finally, we validate enhancer regulation at immunotherapeutically relevant loci by targeting non-coding regulatory elements with potent CRISPR activators and repressors. In summary, our study provides a framework for understanding and manipulating cell-state-specific gene-regulatory cues from human tumor-infiltrating lymphocytes.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Neoplasias/genética , Sequências Reguladoras de Ácido Nucleico , Regulação da Expressão Gênica , Cromatina/genética , Linfócitos do Interstício Tumoral , Elementos Facilitadores Genéticos
2.
Infection ; 52(2): 691-696, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113019

RESUMO

PURPOSE AND METHODS: We present an unusual case of an HIV-negative patient with postpartum pulmonary cryptococcosis and cryptococcemia. RESULTS: The diagnostic methods and treatment of cryptococcosis in a postpartum patient are presented in this case report. Due to anaphylaxis to liposomal amphotericin B, desensitisation to the drug was performed. CONCLUSION: We would like to raise awareness about rare infections such as cryptococcosis in pregnancy and the postpartum period. In addition, we were able to document a successful desensitisation to liposomal amphotericin B.


Assuntos
Anfotericina B , Criptococose , Cryptococcus neoformans , Infecções por HIV , Gravidez , Feminino , Humanos , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Período Pós-Parto , Infecções por HIV/tratamento farmacológico , Antifúngicos/uso terapêutico
3.
Int J Mol Sci ; 25(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39000582

RESUMO

The impact of the HER4 receptor on the growth and treatment of estrogen receptor-positive breast cancer is widely uncertain. Using CRISPR/Cas9 technology, we generated stable HER4 knockout variants derived from the HER4-positive MCF-7, T-47D, and ZR-75-1 breast cancer cell lines. We investigated tumor cell proliferation as well as the cellular and molecular mechanisms of tamoxifen, abemaciclib, AMG232, and NRG1 treatments as a function of HER4 in vitro. HER4 differentially affects the cellular response to tamoxifen and abemaciclib treatment. Most conspicuous is the increased sensitivity of MCF-7 in vitro upon HER4 knockout and the inhibition of cell proliferation by NRG1. Additionally, we assessed tumor growth and immunological effects as responses to tamoxifen and abemaciclib therapy in humanized tumor mice (HTM) based on MCF-7 HER4-wildtype and the corresponding HER4-knockout cells. Without any treatment, the enhanced MCF-7 tumor growth in HTM upon HER4 knockout suggests a tumor-suppressive effect of HER4 under preclinical but human-like conditions. This phenomenon is associated with an increased HER2 expression in MCF-7 in vivo. Independent of HER4, abemaciclib and tamoxifen treatment considerably inhibited tumor growth in these mice. However, abemaciclib-treated hormone receptor-positive breast cancer patients with tumor-associated mdm2 gene copy gains or pronounced HER4 expression showed a reduced event-free survival. Evidently, the presence of HER4 affects the efficacy of tamoxifen and abemaciclib treatment in different estrogen receptor-positive breast cancer cells, even to different extents, and is associated with unfavorable outcomes in abemaciclib-treated patients.


Assuntos
Aminopiridinas , Benzimidazóis , Neoplasias da Mama , Proliferação de Células , Receptor ErbB-4 , Tamoxifeno , Animais , Humanos , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Camundongos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Células MCF-7 , Receptor ErbB-4/metabolismo , Receptor ErbB-4/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética
4.
Int J Cancer ; 153(10): 1854-1867, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37555668

RESUMO

The cellular basis of the apparent aggressiveness in lung cancer is poorly understood but likely associated with functional or molecular features of disseminated cancer cells (DCCs). DCCs from epithelial cancers are mostly detected by antibodies directed against histogenetic markers such as cytokeratin or EpCAM. It has been argued that marker-negative metastatic founder cells might escape detection. We therefore used ex vivo sphere formation for functional detection of candidate metastasis founders. We generated cell suspensions from 199 LN samples of 131 lung cancer patients and placed them into non-adherent cell culture. Sphere formation was associated with detection of DCCs using EpCAM immunocytology and with significantly poorer prognosis. The prognostic impact of sphere formation was strongly associated with high numbers of EpCAM-positive DCCs and aberrant genotypes of expanded spheres. We also noted sphere formation in patients with no evidence of lymphatic spread, however such spheres showed infrequent expression of signature genes associated with spheres from EpCAM-positive samples and displayed neither typical lung cancer mutations (KRAS, TP53, ERBB1) nor copy number variations, but might be linked to disease progression >5 years post curative surgery. We conclude that EpCAM identifies relevant disease-driving DCCs, that such cells can be expanded for model generation and that further research is needed to clarify the functional and prognostic role of rare EpCAM-negative sphere forming cells.


Assuntos
Moléculas de Adesão Celular , Neoplasias Pulmonares , Humanos , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Variações do Número de Cópias de DNA , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Linfonodos/patologia
5.
Br J Cancer ; 128(6): 1134-1147, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36572733

RESUMO

BACKGROUND: Recently, molecular tumour boards (MTBs) have been integrated into the clinical routine. Since their benefit remains debated, we assessed MTB outcomes in the Comprehensive Cancer Center Ostbayern (CCCO) from 2019 to 2021. METHODS AND RESULTS: In total, 251 patients were included. Targeted sequencing was performed with PCR MSI-evaluation and immunohistochemistry for PD-L1, Her2, and mismatch repair enzymes. 125 treatment recommendations were given (49.8%). High-recommendation rates were achieved for intrahepatic cholangiocarcinoma (20/30, 66.7%) and gastric adenocarcinoma (10/16, 62.5%) as opposed to colorectal cancer (9/36, 25.0%) and pancreatic cancer (3/18, 16.7%). MTB therapies were administered in 47 (18.7%) patients, while 53 (21.1%) received alternative treatment regimens. Thus 37.6% of recommended MTB therapies were implemented (47/125 recommendations). The clinical benefit rate (complete + partial + mixed response + stable disease) was 50.0% for MTB and 63.8% for alternative treatments. PFS2/1 ratios were 34.6% and 16.1%, respectively. Significantly improved PFS could be achieved for m1A-tier-evidence-based MTB therapies (median 6.30 months) compared to alternative treatments (median 2.83 months; P = 0.0278). CONCLUSION: The CCCO MTB yielded a considerable recommendation rate, particularly in cholangiocarcinoma patients. The discrepancy between the low-recommendation rates in colorectal and pancreatic cancer suggests the necessity of a weighted prioritisation of entities. High-tier recommendations should be implemented predominantly.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias Pancreáticas , Humanos , Ductos Biliares Intra-Hepáticos , Neoplasias Pancreáticas
6.
Cancer Immunol Immunother ; 72(11): 3867-3873, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37580610

RESUMO

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment option for peritoneal carcinomatosis (PC) from colorectal cancer (CRC), which is otherwise a terminal stage of disease. Nevertheless, survival outcomes are only marginally superior to other treatments. This fact highlights the need for better strategies to control intra-abdominal disease recurrence after CRS-HIPEC, including the complementary use of immunotherapies. The aim of this study was therefore to investigate the immune phenotype of T cells in patients with PC. Fifty three patients with CRC (34 patients with PC and 19 patients without PC) were enrolled in a prospective study (clinicaltrials.gov: NCT04108936). Peripheral blood and omental fat were collected to isolate peripheral blood mononuclear cells (PBMCs) and adipose tissue mononuclear cells (ATMCs). These cells were analysed by flow cytometry using a panel focused upon T cell memory differentiation and exhaustion markers. We found a more naïve profile for CD8+ T cells in peripheral blood and intra-abdominal fat of PC patients compared to comparator group (CG) patients. Furthermore, there was an over-representation of CD4+ T cells expressing inhibitory receptors in adipose tissue of PC patients, but not in blood. Our description of intraperitoneal T cell subsets gives us a better understanding of how peritoneal carcinomatosis shapes local immune responses.


Assuntos
Neoplasias Colorretais , Hipertermia Induzida , Neoplasias Peritoneais , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais/tratamento farmacológico , Procedimentos Cirúrgicos de Citorredução , Estudos Prospectivos , Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Quimioterapia do Câncer por Perfusão Regional , Recidiva Local de Neoplasia/terapia , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Taxa de Sobrevida , Estudos Retrospectivos
7.
J Pathol ; 258(3): 250-263, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36148685

RESUMO

In melanoma, immunocytology (IC) after sentinel lymph node disaggregation not only enables better quantification of disseminated cancer cells (DCCs) than routine histopathology (HP) but also provides a unique opportunity to detect, isolate, and analyse these earliest harbingers of metachronous metastasis. Here, we explored lymph node IC in non-small cell lung cancer (NSCLC). For 122 NSCLC patients, 220 lymph nodes (LNs) were split in half and prepared for IC and HP. When both methods were compared, IC identified 22% positive patients as opposed to 4.5% by HP, revealing a much higher sensitivity of IC (p < 0.001). Assessment of all available 2,952 LNs of the same patients by HP uncovered additional patients escaping detection of lymphatic tumour spread by IC alone, consistent with the concept of skip metastasis. A combined lymph node status of IC and complete HP on a larger cohort of patients outperformed all risk factors in multivariable analysis for prognosis (p < 0.001; RR = 2.290; CI 1.407-3.728). Moreover, isolation of DCCs and single-cell molecular characterization revealed that (1) LN-DCCs differ from primary tumours in terms of copy number alterations and selected mutations and (2) critical alterations are acquired during colony formation within LNs. We conclude that LN-IC in NSCLC patients when combined with HP improves diagnostic precision, has the potential to reduce total workload, and facilitates molecular characterization of lymphatically spread cancer cells, which may become key for the selection and development of novel systemic therapies. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Evolução Molecular , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
8.
Biofouling ; 39(6): 661-681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37587856

RESUMO

Marine biofouling is a global problem affecting various industries, particularly the shipping industry due to long-distance voyages across various ecosystems. Therein fouled hulls cause increased fuel consumption, greenhouse gas emissions, and the spread of invasive aquatic species. To counteract these issues, biofouling management plans are employed using manual cleaning protocols and protective coatings. This review provides a comprehensive overview of adhesion strategies of marine organisms, and currently available mitigation methods. Further, recent developments and open challenges of antifouling (AF) and fouling release (FR) coatings are discussed with regards to the future regulatory environment. Finally, an overview of the environmental and economic impact of fouling is provided to point out why and when the use of biocidal solutions is beneficial in the overall perspective.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Biofilmes , Ecossistema , Organismos Aquáticos
9.
Eur Arch Otorhinolaryngol ; 280(1): 315-320, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35852652

RESUMO

PURPOSE: Several theories have been proposed regarding the origin of lateral neck cysts (LNC). Besides complete surgical resection ipsilateral tonsillectomy and dissection of a tract or its remnants is sometimes recommended. In this retrospective trial we wanted to evaluate if patients, who received LNC resection only, develop complications or recurrence to justify this surgical strategy. METHODS: Patients who received LNC resection between 2004 and 2017 at the Ear Nose and Throat Department of a university hospital were included. Data was collected from the clinic database and through a structured telephone interview. RESULTS: A total of 126 patients met the inclusion criteria. In this collective, the diagnosis of a lateral neck cyst was confirmed histologically. Mean age at time of operation was 38 years (± 14.6). The median follow-up time was 7 years (range 3-18). None of the participants experienced recurrent unilateral pharyngitis or tonsillitis during follow-up. Furthermore, there was no case of postoperative peritonsillar, neck phlegmon or neck abscess. No patient reported recurrence of LNC. CONCLUSIONS: Sole complete resection of LNCs is sufficient to avoid postoperative infections and recurrences. Therefore, ipsilateral tonsillectomy and tract dissection is not necessary in routine cases of LNC surgery.


Assuntos
Cistos , Abscesso Peritonsilar , Faringite , Tonsilectomia , Tonsilite , Humanos , Adulto , Tonsilectomia/efeitos adversos , Estudos Retrospectivos , Tonsilite/cirurgia , Cistos/cirurgia , Abscesso Peritonsilar/cirurgia , Recidiva
10.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834884

RESUMO

BAMBI (bone morphogenetic protein and activin membrane-bound inhibitor) is a transmembrane pseudoreceptor structurally related to transforming growth factor (TGF)-ß type 1 receptors (TGF-ß1Rs). BAMBI lacks a kinase domain and functions as a TGF-ß1R antagonist. Essential processes such as cell differentiation and proliferation are regulated by TGF-ß1R signaling. TGF-ß is the best-studied ligand of TGF-ßRs and has an eminent role in inflammation and fibrogenesis. Liver fibrosis is the end stage of almost all chronic liver diseases, such as non-alcoholic fatty liver disease, and at the moment, there is no effective anti-fibrotic therapy available. Hepatic BAMBI is downregulated in rodent models of liver injury and in the fibrotic liver of patients, suggesting that low BAMBI has a role in liver fibrosis. Experimental evidence convincingly demonstrated that BAMBI overexpression is able to protect against liver fibrosis. Chronic liver diseases have a high risk of hepatocellular carcinoma (HCC), and BAMBI was shown to exert tumor-promoting as well as tumor-protective functions. This review article aims to summarize relevant studies on hepatic BAMBI expression and its role in chronic liver diseases and HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Ativinas , Fator de Crescimento Transformador beta/metabolismo , Cirrose Hepática , Proteínas Morfogenéticas Ósseas , Proteínas de Membrana
11.
Int J Cancer ; 150(8): 1357-1372, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34927257

RESUMO

Estrogen receptor-positive breast cancer is a highly prevalent but heterogeneous disease among women. Advanced molecular stratification is required to enable individually most efficient treatments based on relevant prognostic and predictive biomarkers. First objective of our study was the hypothesis-driven discovery of biomarkers involved in tumor progression upon xenotransplantation of Luminal breast cancer into humanized mice. The second objective was the marker validation and correlation with the clinical outcome of Luminal breast cancer disease within the GeparTrio trial. An elevated mdm2 gene copy number was associated with enhanced tumor growth and lung metastasis in humanized tumor mice. The viability, proliferation and migration capacity of inherently mdm2 positive breast cancer cells in vitro were significantly reduced upon mdm2 knockdown or anti-mdm2 targeting. An mdm2 gain significantly correlated with a worse DFS and OS of Luminal breast cancer patients, albeit it was also associated with an enhanced preoperative pathological response rate. We provide evidence for an enhanced Luminal breast cancer stratification based on mdm2. Moreover, mdm2 can potentially be utilized as a therapeutic target in the Luminal subtype.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas Proto-Oncogênicas c-mdm2/genética , Animais , Progressão da Doença , Feminino , Amplificação de Genes , Humanos , Camundongos , Receptores de Estrogênio/metabolismo , Transplante Heterólogo
12.
Nature ; 540(7634): 552-558, 2016 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-27974799

RESUMO

Accumulating data suggest that metastatic dissemination often occurs early during tumour formation, but the mechanisms of early metastatic spread have not yet been addressed. Here, by studying metastasis in a HER2-driven mouse breast cancer model, we show that progesterone-induced signalling triggers migration of cancer cells from early lesions shortly after HER2 activation, but promotes proliferation in advanced primary tumour cells. The switch from migration to proliferation was regulated by increased HER2 expression and tumour-cell density involving microRNA-mediated progesterone receptor downregulation, and was reversible. Cells from early, low-density lesions displayed more stemness features, migrated more and founded more metastases than cells from dense, advanced tumours. Notably, we found that at least 80% of metastases were derived from early disseminated cancer cells. Karyotypic and phenotypic analysis of human disseminated cancer cells and primary tumours corroborated the relevance of these findings for human metastatic dissemination.

13.
Nano Lett ; 21(1): 507-514, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33305952

RESUMO

When T-cells probe their environment for antigens, the bond between the T-cell receptor (TCR) and the peptide-loaded major histocompatibility complex (MHC) is put under tension, thereby influencing the antigen discrimination. Yet, the quantification of such forces in the context of T-cell signaling is technically challenging. Here, we developed a traction force microscopy platform which allows for quantifying the pulls and pushes exerted via T-cell microvilli, in both tangential and normal directions, during T-cell activation. We immobilized specific T-cell activating antibodies on the marker beads used to read out the hydrogel deformation. Microvilli targeted the functionalized beads, as confirmed by superresolution microscopy of the local actin organization. Moreover, we found that cellular components, such as actin, TCR, and CD45 reorganize upon interaction with the beads, such that actin forms a vortex-like ring structure around the beads and TCR is enriched at the bead surface, whereas CD45 is excluded from bead-microvilli contacts.


Assuntos
Ativação Linfocitária , Tração , Receptores de Antígenos de Linfócitos T , Transdução de Sinais , Linfócitos T
14.
Mol Cancer ; 20(1): 74, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33941200

RESUMO

Loss of apical-basal polarity and downregulation of cell-cell contacts is a critical step during the pathogenesis of cancer. Both processes are regulated by the scaffolding protein Pals1, however, it is unclear whether the expression of Pals1 is affected in cancer cells and whether Pals1 is implicated in the pathogenesis of the disease.Using mRNA expression data and immunostainings of cancer specimen, we show that Pals1 is frequently downregulated in colorectal cancer, correlating with poorer survival of patients. We further found that Pals1 prevents cancer cell metastasis by controlling Rac1-dependent cell migration through inhibition of Arf6, which is independent of the canonical binding partners of Pals1. Loss of Pals1 in colorectal cancer cells results in increased Arf6 and Rac1 activity, enhanced cell migration and invasion in vitro and increased metastasis of transplanted tumor cells in mice. Thus, our data reveal a new function of Pals1 as a key inhibitor of cell migration and metastasis of colorectal cancer cells. Notably, this new function is independent of the known role of Pals1 in tight junction formation and apical-basal polarity.


Assuntos
Fator 6 de Ribosilação do ADP/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Membrana/metabolismo , Núcleosídeo-Fosfato Quinase/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Movimento Celular/fisiologia , Células HCT116 , Xenoenxertos , Humanos , Camundongos , Invasividade Neoplásica/patologia
15.
Biochemistry ; 59(45): 4421-4428, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33147967

RESUMO

Lipid transfer from lipoprotein particles to cells is essential for lipid homeostasis. High-density lipoprotein (HDL) particles are mainly captured by cell membrane-associated scavenger receptor class B type 1 (SR-B1) from the bloodstream, while low-density and very-low-density lipoprotein (LDL and VLDL, respectively) particles are mostly taken up by receptor-mediated endocytosis. However, the role of the target lipid membrane itself in the transfer process has been largely neglected so far. Here, we study how lipoprotein particles (HDL, LDL, and VLDL) interact with synthetic lipid bilayers and cell-derived membranes and transfer their cargo subsequently. Employing cryo-electron microscopy, spectral imaging, and fluorescence (cross) correlation spectroscopy allowed us to observe integration of all major types of lipoprotein particles into the membrane and delivery of their cargo in a receptor-independent manner. Importantly, the biophysical properties of the target cell membranes change upon delivery of cargo. The concept of receptor-independent interaction of lipoprotein particles with membranes helps us to better understand lipoprotein particle biology and can be exploited for novel treatments of dyslipidemia diseases.


Assuntos
Membrana Celular/metabolismo , Lipoproteínas/metabolismo , Transporte Biológico , Bicamadas Lipídicas/metabolismo , Microscopia de Força Atômica
16.
Digestion ; 101(2): 184-190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30820016

RESUMO

BACKGROUND AND AIM: According to several guidelines, both invasive and non-invasive tests can be used to detect Helicobacter pylori (H. pylori). Invasive methods include H. pylori culture, histological staining, rapid urease tests (RUTs) and PCR. Non-invasive methods include urease breath test, stool antigen and serum IgG testing. The aim of our study was to compare all commercially available RUTs and histology in Germany. MATERIAL AND METHODS: One hundred fifty patients were enrolled in our study, irrespective of proton pump inhibitors (PPIs) or antibiotic use. If the results of RUTs and histology were diverging, real-time PCR to detect H. pylori DNA was undertaken. RESULTS: We detected no differences in the sensitivity or specificity between the different RUTs. In PPI and/or antibiotic-treated patients, RUTs seemed to be more sensitive for the detection of H. pylori infection compared to histology. In addition to the cheaper price of RUTs, they are also quicker to process. We show that histological staining in patients with signs of gastritis is expensive and not necessary, if there are no additional histological questions besides H. pylori status. CONCLUSIONS: In conclusion, we consider RUTs to be cheap and fast alternatives to histology in patients with endoscopic signs of gastritis, independently of whether PPIs or antibiotic are used. Histological evaluation is expensive, time consuming and may be unnecessary in some cases.


Assuntos
Testes Respiratórios/métodos , Gastrite/diagnóstico , Gastroscopia/estatística & dados numéricos , Urease/análise , Idoso , Antibacterianos/uso terapêutico , Feminino , Gastrite/microbiologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Inibidores da Bomba de Prótons/uso terapêutico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estômago/patologia
17.
Int J Mol Sci ; 21(21)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33120934

RESUMO

Due to the global rise of type 2 diabetes mellitus (T2DM) in combination with insulin resistance, novel compounds to efficiently treat this pandemic disease are needed. Screening for compounds that induce the translocation of glucose transporter 4 (GLUT4) from the intracellular compartments to the plasma membrane in insulin-sensitive tissues is an innovative strategy. Here, we compared the applicability of three fluorescence microscopy-based assays optimized for the quantitation of GLUT4 translocation in simple cell systems. An objective-type scanning total internal reflection fluorescence (TIRF) microscopy approach was shown to have high sensitivity but only moderate throughput. Therefore, we implemented a prism-type TIR reader for the simultaneous analysis of large cell populations grown in adapted microtiter plates. This approach was found to be high throughput and have sufficient sensitivity for the characterization of insulin mimetic compounds in live cells. Finally, we applied confocal microscopy to giant plasma membrane vesicles (GPMVs) formed from GLUT4-expressing cells. While this assay has only limited throughput, it offers the advantage of being less sensitive to insulin mimetic compounds with high autofluorescence. In summary, the combined implementation of different fluorescence microscopy-based approaches enables the quantitation of GLUT4 translocation with high throughput and high content.


Assuntos
Membrana Celular/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Microscopia de Fluorescência/métodos , Animais , Células CHO , Cricetulus , Células HeLa , Humanos , Transporte Proteico
18.
Chemistry ; 25(42): 9870-9874, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31132189

RESUMO

Surface modification with polyphenolic molecules has been pursued in biomedical materials owing to their antioxidant, anti-inflammatory, and antimicrobial characteristics. Recently, the use of silicic acid (Siaq ) as a mediator for efficient surface deposition of tannic acid (TA) was reported, but the postulated Si-TA polymeric networks were not characterized. Herein, we present unambiguous evidence for silicate-TA networks that involve Si-O-C motifs by using solid-state NMR spectroscopy, further supported by XPS and ToF-SIMS. By using QCM-D we demonstrate the advantages of Siaq , compared to using transition-metal ions, to improve the coating efficiency under mildly acidic conditions. The presented homogenous coating buildup and validated applicability in inorganic buffers broadens the use of TA for surface modifications in technological and biomedical applications.


Assuntos
Materiais Revestidos Biocompatíveis/química , Fenóis/química , Silicatos/química , Taninos/química , Antibacterianos/química , Antioxidantes/química , Materiais Biocompatíveis/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Polímeros/química , Propriedades de Superfície
19.
Langmuir ; 35(9): 3327-3336, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30741549

RESUMO

Tannic acid (TA) adheres to a broad variety of different materials and forms versatile surface coatings for technical and biological applications. In mild alkaline conditions, autoxidation processes occur and a firm monolayer is formed. Up to now, thicker coatings are obtained in only a cross-linked multilayer fashion. This study presents an alternative method to form continuous TA coatings using orthosilicic acid (Siaq). Adsorption kinetics and physical properties of TA coatings in the presence of Siaq were determined using a quartz-crystal microbalance and nanoplasmonic spectroscopy. An in situ TA layer thickness of 200 nm was obtained after 24 h in solutions supplemented with 80 µM Siaq. Dry-state measurements indicated a highly hydrated layer in situ. Furthermore, chemical analysis by Fourier transform infrared spectroscopy revealed possible complexation of TA by Siaq, whereas UV-vis spectroscopy did not indicate an interaction of Siaq in the autoxidation process of TA. Investigation of additional metalloid ions showed that germanic acid was also able to initiate a continuous coating formation of TA, whereas boric acid prevented the polymerization process. In comparison to that of TA, the coating formation of pyrogallol (PG) and gallic acid (GA) was not affected by Siaq. PG formed continuous coatings also without Siaq, whereas GA formed only a monolayer in the presence of Siaq. However, Siaq induced a continuous layer formation of ellagic acid. These results indicate the specific importance of orthosilicic acid in the coating formation of polyphenolic molecules with multiple ortho-dihydroxy groups and open new possibilities to deposit TA on interfaces.


Assuntos
Nanoestruturas/química , Ácido Silícico/química , Taninos/química , Adsorção , Ácido Gálico/química , Oxirredução , Polimerização , Pirogalol/química , Propriedades de Superfície
20.
Mediators Inflamm ; 2019: 8274903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30804708

RESUMO

INTRODUCTION: Recent studies have shown that acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) may serve as important diagnostic and therapeutic targets in sepsis. Since polymorphonuclear neutrophils (PMNs) play a pivotal role in the early phase of sepsis, we evaluated the potential therapeutic effects of cholinesterase inhibitors on PMN functions during cecal ligation and puncture- (CLP-) induced sepsis and investigated the roles of AChE and BChE as inflammatory markers under standardized experimental conditions. METHODS: Sham surgery or CLP was performed in male Wistar rats (n = 60). Animals were randomized into four groups: physostigmine, 100 µg/kg; neostigmine, 75 µg/kg; 0.9% saline (control group); and sham group, each applied four times over 24 h. The levels of reactive oxygen species (ROS) production and CD11b/CD62l expression were quantified by flow cytometry at t = 0, 6, 15, 20, and 24 h. Blood gas analysis as well as AChE and BChE activity levels was measured by validated point-of-care measurements. Clinical scores and survival times were determined. RESULTS: CLP induced a significant increase in ROS production and CD11b upregulation by rat PMNs. Treatment with physostigmine or neostigmine significantly reduced ROS production and CD11b upregulation by PMNs 20 h after CLP induction. In physostigmine-treated animals, survival times were significantly improved compared to the control animals, but not in neostigmine-treated animals. While AChE activity significantly decreased in the control animals at t > 6 h, AChE activity did not change in the sham group. BChE activity decreased at t > 20 h in the control animals. CONCLUSION: While AChE activity may serve as an acute inflammatory marker, BChE activity shows a delayed decrease. Administration of centrally acting physostigmine in CLP-induced sepsis in rats has protective effects on PMN functions and improves survival times, which may be of interest in clinical practice.


Assuntos
Acetilcolinesterase/metabolismo , Biomarcadores/metabolismo , Butirilcolinesterase/metabolismo , Neostigmina/uso terapêutico , Neutrófilos/efeitos dos fármacos , Fisostigmina/uso terapêutico , Sepse/tratamento farmacológico , Sepse/metabolismo , Animais , Gasometria , Masculino , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
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