34 research outputs found

    G-protein signaling: back to the future

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    Heterotrimeric G-proteins are intracellular partners of G-protein-coupled receptors (GPCRs). GPCRs act on inactive Gα·GDP/GÎČÎł heterotrimers to promote GDP release and GTP binding, resulting in liberation of Gα from GÎČÎł. Gα·GTP and GÎČÎł target effectors including adenylyl cyclases, phospholipases and ion channels. Signaling is terminated by intrinsic GTPase activity of Gα and heterotrimer reformation — a cycle accelerated by ‘regulators of G-protein signaling’ (RGS proteins). Recent studies have identified several unconventional G-protein signaling pathways that diverge from this standard model. Whereas phospholipase C (PLC) ÎČ is activated by Gαq and GÎČÎł, novel PLC isoforms are regulated by both heterotrimeric and Ras-superfamily G-proteins. An Arabidopsis protein has been discovered containing both GPCR and RGS domains within the same protein. Most surprisingly, a receptor-independent Gα nucleotide cycle that regulates cell division has been delineated in both Caenorhabditis elegans and Drosophila melanogaster. Here, we revisit classical heterotrimeric G-protein signaling and explore these new, non-canonical G-protein signaling pathways

    Cold Atmospheric Plasma Treatment of Chondrosarcoma Cells Affects Proliferation and Cell Membrane Permeability

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    Chondrosarcoma is the second most common malign bone tumor in adults. Surgical resection of the tumor is recommended because of its resistance to clinical treatment such as chemotherapy and radiation therapy. Thus, the prognosis for patients mainly depends on sufficient surgical resection. Due to this, research on alternative therapies is needed. Cold atmospheric plasma (CAP) is an ionized gas that contains various reactive species. Previous studies have shown an anti-oncogenic potential of CAP on different cancer cell types. The current study examined the effects of treatment with CAP on two chondrosarcoma cell lines (CAL-78, SW1353). Through proliferation assay, the cell growth after CAP-treatment was determined. A strong antiproliferative effect for both cell lines was detected. By fluorescein diacetate (FDA) assay and ATP release assay, alterations in the cell membrane and associated translocation of low molecular weight particles through the cytoplasmic membrane were observed. In supernatant, the non-membrane-permeable FDA and endogenously synthesized ATP detected suggest an increased membrane permeability after CAP treatment. Similar results were shown by the dextran-uptake assay. Furthermore, fluorescence microscopic G-/F-actin assay was performed. G- and F-actin were selectively dyed, and the ratio was measured. The presented results indicate CAP-induced changes in cell membrane function and possible alterations in actin-cytoskeleton, which may contribute to the antiproliferative effects of CAP

    New Approach against Chondrosoma Cells—Cold Plasma Treatment Inhibits Cell Motility and Metabolism, and Leads to Apoptosis

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    (1) Background: Chondrosarcoma (CS) is a malignant primary bone tumor with a cartilaginous origin. Its slow cell division and severely restricted vascularization are responsible for its poor responsiveness to chemotherapy and radiotherapy. The decisive factor for the prognosis of CS patients is the only adequate therapy—surgical resection. Cold atmospheric pressure plasma (CAP) is emerging as a new option in anti-cancer therapy. Its effect on chondrosarcomas has been poorly investigated. (2) Methods: Two CS cell lines—SW 1353 and CAL 78—were used. Various assays, such as cell growth kinetics, glucose uptake, and metabolic activity assay, along with two different apoptosis assays were performed after CAP treatment. A radius cell migration assay was used to examine cell motility. (3) Results: Both cell lines showed different growth behavior, which was taken into account when using the assays. After CAP treatment, a reduction in metabolic activity was observed in both cell lines. The immediate effect of CAP showed a reduction in cell numbers and in influence on this cell line’s growth rate. The measurement of the glucose concentration in the cell culture medium showed an increase after CAP treatment. Live-dead cell imaging shows an increase in the proportion of dead cells over the incubation time for both cell lines. There was a significant increase in apoptotic signals after 48 h and 72 h for both cell lines in both assays. The migration assay showed that CAP treatment inhibited the motility of chondrosarcoma cells. The effects in all experiments were related to the duration of CAP exposure. (4) Conclusions: The CAP treatment of CS cells inhibits their growth, motility, and metabolism by initiating apoptotic processes

    Impact of COVID-19 on gynaecological patient care: results of patient’s survey with 327 patients

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    Purpose!#!The pandemic SARS-CoV-2 poses new and unprecedented challenges for health care systems on a national and global level. Although the current situation has been going on for more than 1 year, there is limited data on the impact of the pandemic on general hospital and medical practice care. This survey captures the perspective of patients with gynaecological diseases of this impact.!##!Methods!#!Using a paper-based questionnaire, 327 patients were asked about medical care and their experiences during the pandemic at the University Hospital Bonn and the University Hospital Charité Berlin. The study was performed from the 1st June to 30th September 2020.!##!Results!#!A total of 327 patients participated in the study: 156 stated to have been tested for coronavirus, and 1 patient reported a positive test. 41.3% of the patients felt insecure about the current situation, 30.4% were concerned about the risk of infection during the hospital stay. The pandemic-specific measures in hospitals and medical practices unsettled 6.8% of patients. 18.1% of patients feared that their gynaecological disease would not be treated adequately due to the pandemic. 55.7% of patients reported that their confidence in their physicians has increased during the pandemic.!##!Conclusion!#!The results show that patients' confidence in the healthcare system and the physicians acting significantly increased during the COVID-19 crisis. Transparent and comprehensive information policy regarding actions and restrictions within the COVID-19 crisis eases patients concerns and improves patients' confidence in their physicians, which is crucial for a successful treatment's outcome
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