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1.
RSC Adv ; 14(6): 3845-3856, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38274173

ABSTRACT

The effect of two atmospheric post-treatment conditions directly after the KOH activation of polyacrylonitrile-based nanofibres is studied in this work. As post-treatment different N2 : O2 flow conditions, namely high O2-flow and low O2-flow, are applied and their impact on occurring reactions and carbon nanofibres' properties is studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Raman spectroscopy, elemental analysis and CO2 and Ar gas adsorption. At high O2-flow conditions a pyrophoric effect was observed on the KOH-activated carbon nanofibers. Based on the obtained results from the TGA and DSC the pyrophoric effect is attributed to the oxidation reactions of metallic potassium formed during the KOH activation process and a consequent carbon combustion reaction. Suppression of this pyrophoric effect is achieved using the low O2-flow conditions due to a lower heat formation of the potassium oxidation and the absence of carbon combustion. Compared to the high O2-flow samples no partial destruction of the carbon nanofibers is observed in the SEM images. The determination of the adsorption isotherms, the surface area, the pore size distribution and the isosteric enthalpies of adsorption show the superior properties under low O2-flow conditions. The present micropore volume is increased from 0.424 cm3 g-1 at high O2-flow to 0.806 cm3 g-1 for low O2-flow samples, resulting in an increase of CO2 adsorption capacity of 38% up to 6.6 mmol g-1 at 1 bar. This significant improvement clearly points out the importance of considering highly exothermic potassium oxidation reactions and possible post-treatment strategies when applying KOH activation to electrospun carbon nanofiber materials.

2.
Cell Calcium ; 104: 102572, 2022 06.
Article in English | MEDLINE | ID: mdl-35366518

ABSTRACT

Wolfram syndrome is a rare genetic disorder characterized by endocrine dysfunction and progressive neurodegeneration. By targeting intracellular calcium dysregulations, a sigma-1 receptor agonist rescued neurological deficits in preclinical models of Wolfram syndrome.


Subject(s)
Wolfram Syndrome , Calcium , Humans , Mitochondria , Wolfram Syndrome/drug therapy , Wolfram Syndrome/genetics
3.
Commun Biol ; 5(1): 202, 2022 03 03.
Article in English | MEDLINE | ID: mdl-35241781

ABSTRACT

Drug treatment against liver cancer has limited efficacy due to heterogeneous response among liver cancer subtypes. In addition, the functional biophysical phenotypes which arise from this heterogeneity and contribute to aggressive invasive behavior remain poorly understood. This study interrogated how heterogeneity in liver cancer subtypes contributes to differences in invasive phenotypes and drug response. Utilizing histological analysis, quantitative 2D invasion metrics, reconstituted 3D hydrogels, and bioinformatics, our study linked cytoskeletal dynamics to differential invasion profiles and drug resistance in liver cancer subtypes. We investigated cytoskeletal regulation in 2D and 3D culture environments using two liver cancer cell lines, SNU-475 and HepG2, chosen for their distinct cytoskeletal features and invasion profiles. For SNU-475 cells, a model for aggressive liver cancer, many cytoskeletal inhibitors abrogated 2D migration but only some suppressed 3D migration. For HepG2 cells, cytoskeletal inhibition did not significantly affect 3D migration but did affect proliferative capabilities and spheroid core growth. This study highlights cytoskeleton driven phenotypic variation, their consequences and coexistence within the same tumor, as well as efficacy of targeting biophysical phenotypes that may be masked in traditional screens against tumor growth.


Subject(s)
Cytoskeleton , Liver Neoplasms , Cell Line , Humans , Hydrogels/pharmacology
4.
Aktuelle Urol ; 53(1): 75-81, 2022 Feb.
Article in German | MEDLINE | ID: mdl-31195415

ABSTRACT

BACKGROUND: The Onkonet database has been developed and coordinated by the Berliner Tumorzentrum e. V. (http://www.prostata-ca.net) and contains data on pre-, peri- and postoperative parameters of radical prostatectomy documented since January 2005. With its user-friendly interface and its integrated benchmarking tool, the main goal of Onkonet was to outline and improve the surgical care of prostate cancer patients in Germany. This study aimed to analyse all Onkonet data documented from the beginning of the project until June 2018. We focused on the completeness and plausibility of data to investigate and define the possibilities and limits of further analyses. PATIENTS AND METHODS: All patients who underwent radical prostatectomy in one of the urological clinics participating in this project until June 2018 were included in this retrospective study. The completeness of all documented patient data was analysed using Excel 2013. The statistical analysis was descriptive. RESULTS: A total of 21 474 patients were documented in Onkonet. 58,6 % (12 591) of them had a complete dataset including date of birth, date of surgery, dates of hospitalisation and discharge, initial PSA value, Gleason score of the biopsy, clinical T stage, pathological T stage, pathological Gleason score, as well as information on the surgical technique. Mean completeness of pre-operative parameters was 26,8 %, of hospitalisation parameters 64,5 %, and of pathological parameters 58,1 %. Amongst these, the documentation of the pathological T stage was complete in 80,1 %, documentation of N stage in 78,8 %, of M stage in 74,8 %, of pathological Gleason Score in 78,7 %, and of R1 status in 78,7 %. Completeness of follow-up data was 8,1 %, with PSA data being available in 27,2 %, continence data in 23,0 %, and potency data in 13,9 %. CONCLUSIONS: Comprising 21 474 documented patients and over 200 parameters, Onkonet is one of the most comprehensive clinical registers for the documentation of prostate cancer patients in Germany. The data analysis showed that the limitations of such a database are mainly due to the high number of parameters and the high susceptibility to errors due to manual data submission.


Subject(s)
Prostatectomy , Prostatic Neoplasms , Databases, Factual , Germany , Humans , Internet , Male , Neoplasm Grading , Prostate-Specific Antigen , Prostatic Neoplasms/surgery , Retrospective Studies
5.
FASEB J ; 35(10): e21873, 2021 10.
Article in English | MEDLINE | ID: mdl-34499766

ABSTRACT

Calcium (Ca2+ ) signaling is critical for neuronal functioning and requires the concerted interplay of numerous Ca2+ -binding proteins, including neuronal calcium sensor 1 (NCS1). Although an important role of NCS1 in neuronal processes and in neurodevelopmental and neurodegenerative diseases has been established, the underlying mechanisms remain enigmatic. Here, we systematically investigated the functions of NCS1 in the brain. Using Golgi-Cox staining, we observed a reduction in dendritic complexity and spine density in the prefrontal cortex and the dorsal hippocampus of Ncs1-/- mice, which may underlie concomitantly observed deficits in memory acquisition. Subsequent RNA sequencing of Ncs1-/- and Ncs1+/+ mouse brain tissues revealed that NCS1 modulates gene expression related to neuronal morphology and development. Investigation of developmental databases further supported a molecular role of NCS1 during brain development by identifying temporal gene expression patterns. Collectively, this study provides insights into NCS1-dependent signaling and lays the foundation for a better understanding of NCS1-associated diseases.


Subject(s)
Calcium/metabolism , Hippocampus/pathology , Nervous System Diseases/pathology , Neuronal Calcium-Sensor Proteins/physiology , Neurons/pathology , Neuropeptides/physiology , Animals , Hippocampus/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Nervous System Diseases/etiology , Nervous System Diseases/metabolism , Neurons/metabolism , RNA-Seq , Signal Transduction , Transcriptome
6.
Mol Neurodegener ; 16(1): 41, 2021 06 26.
Article in English | MEDLINE | ID: mdl-34174909

ABSTRACT

BACKGROUND: After chemotherapy, many cancer survivors suffer from long-lasting cognitive impairment, colloquially known as "chemobrain." However, the trajectories of cognitive changes and the underlying mechanisms remain unclear. We previously established paclitaxel-induced inositol trisphosphate receptor (InsP3R)-dependent calcium oscillations as a mechanism for peripheral neuropathy, which was prevented by lithium pretreatment. Here, we investigated if a similar mechanism also underlay paclitaxel-induced chemobrain. METHOD: Mice were injected with 4 doses of 20 mg/kg paclitaxel every other day to induced cognitive impairment. Memory acquisition was assessed with the displaced object recognition test. The morphology of neurons in the prefrontal cortex and the hippocampus was analyzed using Golgi-Cox staining, followed by Sholl analyses. Changes in protein expression were measured by Western blot. RESULTS: Mice receiving paclitaxel showed impaired short-term spatial memory acquisition both acutely 5 days post injection and chronically 23 days post injection. Dendritic length and complexity were reduced in the hippocampus and the prefrontal cortex after paclitaxel injection. Concurrently, the expression of protein kinase C α (PKCα), an effector in the InsP3R pathway, was increased. Treatment with lithium before or shortly after paclitaxel injection rescued the behavioral, cellular, and molecular deficits observed. Similarly, memory and morphological deficits could be rescued by pretreatment with chelerythrine, a PKC inhibitor. CONCLUSION: We establish the InsP3R calcium pathway and impaired neuronal morphology as mechanisms for paclitaxel-induced cognitive impairment. Our findings suggest lithium and PKC inhibitors as candidate agents for preventing chemotherapy-induced cognitive impairment.


Subject(s)
Chemotherapy-Related Cognitive Impairment/metabolism , Cognition/drug effects , Lithium Chloride/pharmacology , Neuroprotective Agents/pharmacology , Animals , Antineoplastic Agents, Phytogenic/toxicity , Disease Models, Animal , Female , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Mice , Mice, Inbred C57BL , Paclitaxel/toxicity
7.
Curr Opin Physiol ; 17: 115-123, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32864536

ABSTRACT

Wolfram syndrome (WS) is a rare, progressive disorder characterized by childhood-onset diabetes mellitus, optic nerve atrophy, hearing loss, diabetes insipidus, and neurodegeneration. Currently, there is no effective treatment for WS, and patients typically die between 30 and 40 years of age. WS is primarily caused by autosomal recessive mutations in the Wolfram syndrome 1 (WFS1) gene (OMIM 222300), which encodes for wolframin (WFS1). This disorder is therefore a valuable monogenic model for prevalent diseases, particularly diabetes mellitus and neurodegeneration. Whereas reduced survival and secretion are known cellular impairments causing WS, the underlying molecular pathways and the physiological function of WFS1 remain incompletely described. Here, we characterize WFS1 as a regulator of intracellular calcium homeostasis, review our current understanding of the disease mechanism of WS, and discuss candidate treatment approaches. These insights will facilitate identification of new therapeutic strategies not only for WS but also for diabetes mellitus and neurodegeneration.

8.
Proc Natl Acad Sci U S A ; 117(29): 17389-17398, 2020 07 21.
Article in English | MEDLINE | ID: mdl-32632005

ABSTRACT

Wolfram syndrome is a rare multisystem disease characterized by childhood-onset diabetes mellitus and progressive neurodegeneration. Most cases are attributed to pathogenic variants in a single gene, Wolfram syndrome 1 (WFS1). There currently is no disease-modifying treatment for Wolfram syndrome, as the molecular consequences of the loss of WFS1 remain elusive. Because diabetes mellitus is the first diagnosed symptom of Wolfram syndrome, we aimed to further examine the functions of WFS1 in pancreatic ß cells in the context of hyperglycemia. Knockout (KO) of WFS1 in rat insulinoma (INS1) cells impaired calcium homeostasis and protein kinase B/Akt signaling and, subsequently, decreased cell viability and glucose-stimulated insulin secretion. Targeting calcium homeostasis with reexpression of WFS1, overexpression of WFS1's interacting partner neuronal calcium sensor-1 (NCS1), or treatment with calpain inhibitor and ibudilast reversed deficits observed in WFS1-KO cells. Collectively, our findings provide insight into the disease mechanism of Wolfram syndrome and highlight new targets and drug candidates to facilitate the development of a treatment for this disorder and similar diseases.


Subject(s)
Antineoplastic Agents/pharmacology , Calmodulin-Binding Proteins/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Insulin-Secreting Cells/drug effects , Membrane Proteins/metabolism , Pyridines/pharmacology , Wolfram Syndrome/drug therapy , Animals , Calcium/metabolism , Calmodulin-Binding Proteins/genetics , Cell Survival/drug effects , Disease Models, Animal , Endoplasmic Reticulum/metabolism , Gene Expression Regulation , Gene Knockout Techniques , Glycoproteins , Homeostasis , Hyperglycemia , Insulin Secretion , Membrane Proteins/genetics , Receptor, Insulin , Transcriptome , Wolfram Syndrome/genetics
9.
Mol Oncol ; 14(6): 1134-1151, 2020 06.
Article in English | MEDLINE | ID: mdl-32239615

ABSTRACT

Changes in intracellular calcium (Ca2+ ) signaling can modulate cellular machinery required for cancer progression. Neuronal calcium sensor 1 (NCS1) is a ubiquitously expressed Ca2+ -binding protein that promotes tumor aggressiveness by enhancing cell survival and metastasis. However, the underlying mechanism by which NCS1 contributes to increased tumor aggressiveness has yet to be identified. In this study, we aimed to determine (a) whether NCS1 expression changes in response to external stimuli, (b) the importance of NCS1 for cell survival and migration, and (c) the cellular mechanism(s) through which NSC1 modulates these outcomes. We found that NCS1 abundance increases under conditions of stress, most prominently after stimulation with the pro-inflammatory cytokine tumor necrosis factor α, in a manner dependent on nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). We found that NFκB signaling is activated in human breast cancer tissue, which was accompanied by an increase in NCS1 mRNA expression. Further exploration into the relevance of NCS1 in breast cancer progression showed that knockout of NCS1 (NCS1 KO) caused decreased cell survival and motility, increased baseline intracellular Ca2+ levels, and decreased inositol 1,4,5-trisphosphate-mediated Ca2+ responses. Protein kinase B (Akt) activity was decreased in NCS1 KO cells, which could be rescued by buffering intracellular Ca2+ . Conversely, Akt activity was increased in cells overexpressing NCS1 (NCS1 OE). We therefore conclude that NCS1 acts as cellular stress response protein up-regulated by stress-induced NFκB signaling and that NCS1 influences cell survival and motility through effects on Ca2+ signaling and Akt pathway activation.


Subject(s)
Cell Movement/genetics , Neoplasms/genetics , Neoplasms/pathology , Neuronal Calcium-Sensor Proteins/genetics , Neuropeptides/genetics , Stress, Physiological/genetics , Up-Regulation/genetics , Base Sequence , CRISPR-Cas Systems/genetics , Calcium/metabolism , Cell Line, Tumor , Cell Movement/drug effects , Cell Survival/drug effects , Cell Survival/genetics , Chelating Agents/pharmacology , Cytosol/metabolism , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Humans , Inositol 1,4,5-Trisphosphate Receptors/metabolism , NF-kappa B/metabolism , Neuronal Calcium-Sensor Proteins/metabolism , Neuropeptides/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Stress, Physiological/drug effects , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation/drug effects
10.
Sci Rep ; 10(1): 386, 2020 01 15.
Article in English | MEDLINE | ID: mdl-31941974

ABSTRACT

Polycystin 2 (PC2 or TRPP1, formerly TRPP2) is a calcium-permeant Transient Receptor Potential (TRP) cation channel expressed primarily on the endoplasmic reticulum (ER) membrane and primary cilia of all cell and tissue types. Despite its ubiquitous expression throughout the body, studies of PC2 have focused primarily on its role in the kidney, as mutations in PC2 lead to the development of autosomal dominant polycystic kidney disease (ADPKD), a debilitating condition for which there is no cure. However, the endogenous role that PC2 plays in the regulation of general cellular homeostasis remains unclear. In this study, we measure how PC2 expression changes in different pathological states, determine that its abundance is increased under conditions of cellular stress in multiple tissues including human disease, and conclude that PC2-deficient cells have increased susceptibility to cell death induced by stress. Our results offer new insight into the normal function of PC2 as a ubiquitous stress-sensitive protein whose expression is up-regulated in response to cell stress to protect against pathological cell death in multiple diseases.


Subject(s)
Acute Kidney Injury/pathology , Cell Death , Heart Diseases/pathology , Non-alcoholic Fatty Liver Disease/pathology , Protective Agents/metabolism , Reperfusion Injury/pathology , TRPP Cation Channels/metabolism , Acute Kidney Injury/etiology , Acute Kidney Injury/metabolism , Animals , Calcium/metabolism , Endoplasmic Reticulum/metabolism , Heart Diseases/etiology , Heart Diseases/metabolism , Homeostasis , Humans , Male , Mice , Mice, Inbred C57BL , Mutation , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Oxidative Stress , Reperfusion Injury/etiology , Reperfusion Injury/metabolism , TRPP Cation Channels/genetics
11.
Urol Int ; 101(3): 256-262, 2018.
Article in English | MEDLINE | ID: mdl-30253389

ABSTRACT

INTRODUCTION: The purpose of this study was to evaluate whether the number of radical prostatectomies per hospital per year is associated with stage distribution, surgical techniques or quality related outcome in Germany. MATERIALS AND METHODS: A German Internet-based database was analyzed. Hospitals were categorized according to their yearly radical prostatectomy (RP) volume. Patient's characteristics, RP techniques, and outcome-related parameters were compared between the different hospital volume categories. RESULTS: A total of 6,447 patients were analyzed. The highest rate of organ-confined disease and the lowest rate of extracapsular invasion have been demonstrated in very low-volume centres (72.6%

Subject(s)
Prostatectomy/adverse effects , Prostatectomy/statistics & numerical data , Prostatic Neoplasms/surgery , Aged , Blood Loss, Surgical , Germany , Humans , Laparoscopy , Male , Middle Aged , Prostate/pathology , Prostate/surgery , Prostate-Specific Antigen/blood , Prostatic Neoplasms/pathology , Risk , Robotic Surgical Procedures , Seminal Vesicles/pathology , Treatment Outcome
12.
Adv Ther ; 34(2): 576-585, 2017 02.
Article in English | MEDLINE | ID: mdl-28054309

ABSTRACT

INTRODUCTION: The objective of this study was to evaluate changes of patient characteristics and surgical techniques in radical prostatectomy in Germany within the last decade. METHODS: Data from 44 German prostate cancer centers were included in the study. Patients' characteristics (age, initial PSA value), surgical techniques (open vs. minimally invasive approaches), perioperative parameters (operating time, rate of nerve-sparing (NS) radical prostatectomies (RPs), hospitalization time, catheter indwelling time, surgical margin status, number of dissected lymph nodes (LN)), and pathological findings (tumor stage, Gleason score) were analyzed. RESULTS: Data from 11,675 patients who underwent RP between 2005 and 2014 were analyzed. The rate of open RP approaches decreased by 1.7% (p = 0.0164), the rate of minimally invasive approaches increased by 1.8% (p = 0.0164). Robot-assisted RPs (RARP) increased by 4.6% (p < 0.0001). The number of NS procedures and pelvic lymphadenectomy (LA) increased by 4.5% (p < 0.0001) and 4.7% (p < 0.0001), respectively. Catheter indwelling time and hospitalization time decreased by 1 day (p < 0.0001). No change in the rate of positive surgical margins (p = 0.5061) and the ratio of positive lymph nodes removed (p = 0.4628) was observed. The number of Gleason ≤6 tumors decreased significantly (p < 0.0001). CONCLUSIONS: The number of RARP has significantly increased over the past decade and there is a trend towards surgeries on more advanced tumors with higher yields of lymph nodes dissected. At the same time, the rate of nerve-sparing procedures has significantly increased.


Subject(s)
Prostatectomy , Prostatic Neoplasms , Aged , Databases, Factual , Germany/epidemiology , Humans , Male , Margins of Excision , Middle Aged , Minimally Invasive Surgical Procedures/methods , Minimally Invasive Surgical Procedures/statistics & numerical data , Neoplasm Grading , Neoplasm Staging , Operative Time , Prostatectomy/adverse effects , Prostatectomy/methods , Prostatectomy/statistics & numerical data , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Retrospective Studies , Robotic Surgical Procedures/methods , Robotic Surgical Procedures/statistics & numerical data
13.
BJU Int ; 109(3): 355-9, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21883819

ABSTRACT

OBJECTIVES: To report our experience with an Internet-based multicentre database that enables tumour documentation, as well as the collection of quality-related parameters and follow-up data, in surgically treated patients with prostate cancer. The system was used to assess the quality of prostate cancer surgery and to analyze possible time-dependent trends in the quality of care. PATIENTS AND METHODS: An Internet-based database system enabled a standardized collection of treatment data and clinical findings from the participating urological centres for the years 2005-2009. An analysis was performed aiming to evaluate relevant patient characteristics (age, pathological tumour stage, preoperative International Index of Erectile Function-5 score), intra-operative parameters (operating time, percentage of nerve-sparing operations, complication rate, transfusion rate, number of resected lymph nodes) and postoperative parameters (hospitalization time, re-operation rate, catheter indwelling time). Mean values were calculated and compared for each annual cohort from 2005 to 2008. The overall survival rate was also calculated for a subgroup of the Berlin patients. RESULTS: A total of 914, 1120, 1434 and 1750 patients submitted to radical prostatectomy in 2005, 2006, 2007 and 2008 were documented in the database. The mean age at the time of surgery remained constant (66 years) during the study period. More than half the patients already had erectile dysfunction before surgery (median International Index of Erectile Function-5 score of 19-20). During the observation period, there was a decrease in the percentage of pT2 tumours (1% in 2005; 64% in 2008) and a slight increase in the percentage of patients with lymph node metastases (8% in 2005; 10% in 2008). No time trend was found for the operating time (142-155 min) or the percentage of nerve-sparing operations (72-78% in patients without erectile dysfunction). A decreasing frequency was observed for the parameters: blood transfusions (1.9% in 2005; 0.5% in 2008), postoperative bleeding (2.6%; 1.2%) and re-operations (4.5%; 2.8%). The mean hospitalization time decreased accordingly (10 days in 2005; 8 days in 2008). The examined subcohort had an overall mortality of 1.5% (median follow-up of 3 years). CONCLUSIONS: An Internet-based database system for tumour documentation in patients with prostate cancer enables the collection and assessment of important parameters for the quality of care and outcomes. The participating centres show an improvement in the quality of surgical management, including a reduction of the complication rate.


Subject(s)
Prostatectomy/trends , Prostatic Neoplasms/surgery , Aged , Data Collection , Databases as Topic , Germany , Humans , Internet , Length of Stay , Male , Prostatectomy/standards , Quality of Life
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