Inhibition of HERG1 K+ channel protein expression decreases cell proliferation of human small cell lung cancer cells

HERG (human ether-à-go-go-related gene) K+ currents fulfill important ionic functions in cardiac and other excitable cells. In addition, HERG channels influence cell growth and migration in various types of tumor cells. The mechanisms underlying these functions are still not resolved. Here, we investigated the role of HERG channels for cell growth in a cell line (SW2) derived from small cell lung cancer (SCLC), a malignant variant of lung cancer. The two HERG1 isoforms (HERG1a, HERG1b) as well as HERG2 and HERG3 are expressed in SW2 cells. Inhibition of HERG currents by acute or sustained application of E-4031, a specific ERG channel blocker, depolarized SW2 cells by 10–15 mV. This result indicated that HERG K+ conductance contributes considerably to the maintenance of the resting potential of about −45 mV. Blockage of HERG channels by E-4031 for up to 72 h did not affect cell proliferation. In contrast, siRNA-induced inhibition of HERG1 protein expression decreased cell proliferation by about 50%. Reduction of HERG1 protein expression was confirmed by Western blots. HERG current was almost absent in SW2 cells transfected with siRNA against HERG1. Qualitatively similar results were obtained in three other SCLC cell lines (OH1, OH3, H82), suggesting that the HERG1 channel protein is involved in SCLC cell growth, whereas the ion-conducting function of HERG1 seems not to be important for cell growth

Die modifizierte SLAM (scapholunate axis method) Technik zur sekundären SL-Band-Rekonstruktion – Erste Ergebnisse

Background The common techniques for scapholunate (SL) ligament reconstruction achieve pain relief and maintenance of reposition at the expense of mobility and grip strength. In contrast, the scapholunate axis method (SLAM) technique seems to stabilise the scaphoid and lunate bones without a loss of function. We modified the technique with an additional anchor fixation of the tendon graft to the capitate bone in order to prevent palmar dislocation of the scaphoid bone. Purpose This study aimed to examine whether or not it is possible to stabilise the scaphoid and lunate bones and to reduce pain without a loss of function and grip strength using the modified SLAM technique. Patients and Methods The SLAM technique was performed on 5 male patients aged between 36 and 60 years with an SL ligament lesion (3-10 months old). Preoperatively and after 12 months, the postoperative range of motion, grip strength, pain, SL angle, DASH Score and Mayo Wrist Score were assessed and compared to each other. Results An improvement of the DASH Score (60.4 to 34.4 on average) and the Mayo Wrist Score (41 to 74 on average) was observed at the 12-month follow-up. Grip strength was enhanced from an average of 24.6 kg to 38 kg. Pain was improved from an average of 1.4 to 0.2 (at rest) and from 5.4 to 1.4 (under load). The SL angle changed only marginally from an average of 64.8 degrees preoperatively to 63.2 degrees postoperatively. The average range of motion was improved (extension/flexion: 58-0-60 vs. 50-0-49; radial/ulnar duction: 19-0-45 vs. 15-0-25 und supination/pronation: 87-0-90 vs. 81-0-81): However, function did not improve in every patient and all planes. Conclusion The modified SLAM technique improved the DASH Score, the Mayo Wrist Score, grip strength and pain. However, the SL angle and range of motion did not improve in every patient and plane. Consequently, it cannot be confirmed that the modified SLAM technique ensures a reliable stabilisation of the scaphoid and lunate bones and reduction of pain without a loss of function

Biopolymer Systems in Soft Tissue Engineering: Cell Compatibility and Effect Studies Including Material, Catalyst, and Surface Properties

Cell compatibility of biomaterials is one of the most important issues in tissue engineering. It is affected by the catalyst, the chemical composition, and the surface topography of the material. Our aim was to study the influence of these factors for three standard FDA-approved biopolymers on the proliferation of preadipocytes. The analyzed materials were polyesters, which were synthesized by ring-opening polymerization. Tin(II) octanoate is the standard catalysts for the ring-opening polymerization; however, it is considered to be cytotoxic. Therefore, we compare its compatibility with iron catalysts. Our study suggests that neither polymers nor catalysts or mechanical properties have a significant impact on cell compatibility in short-term 2D cell cultures in vitro. In contrast, nanoroughness can influence how cells attach and spread in a material, showing an influence on preadipocyte proliferation. Higher nanoroughness leads to higher cell compatibility, which becomes more pronounced with time

Septic arthritis of the knee: Presentation of a novel irrigation-suction system tested in a cadaver study

<p>Abstract</p> <p>Background</p> <p>The established treatment for bacterial arthritis of the knee joint is arthroscopic surgery with irrigation and debridement. The aim of this article is to summarize the relevant data in treating bacterial arthritis of the knee joint, and based on these findings to present a novel irrigation suction system, tested in a cadaver study, as an additional tool in the postoperative treatment phase of arthroscopic surgery for knee joint infections.</p> <p>Method</p> <p>The novel automated irrigation-suction system presented here was compared to conventional continuous suction irrigation in a total of six knee joints. All knee joints were filled with 80 ml methylene blue stain and rinsed by two different methods. Fluid specimens were taken after ten and twenty minutes to be compared by photometric extinction measurement at a wave length of 500 nm.</p> <p>Results</p> <p>After ten minutes, the average extinction was e_1C= 0.8 for the continuous suction irrigation and e_1N= 0.4 for the novel irrigation-suction system. After twenty minutes, we recorded an average extinction of e_2C= 0.3 for continuous suction irrigation and e_2N= 0.001 for the novel irrigation-suction system. The students <it>t-</it>test revealed superior results after ten and twenty minutes of washing out the knee joints with a p < 0.001 for the novel irrigation-suction system.</p> <p>Conclusion</p> <p>A novel irrigation-suction system may be an effective tool for postoperative knee joint irrigation in arthroscopic therapy for bacterial arthritis of the knee. Further animal studies are needed to verify the effects in vivo.</p