Tip Design of Hemodialysis Catheters Influences Thrombotic Events and Replacement Rate.

OBJECTIVE/BACKGROUND: Central venous tunnelled hemodialysis catheters (CVTC) are used for initial vascular access in patients with renal failure. Tip design of the CVTC may play an important role in catheter function and complication rates, influencing adequate hemodialysis treatment of these patients. METHODS: This prospective, observational cohort study compared the function and complication rates of two CVTCs in patients with end stage renal disease (ESRD) within a follow-up period of 24 months. The study included patients with ESRD who received either a CVTC with a split tip (ST) or a shotgun tip (SG). All patients underwent dialysis within 24 h of intervention. Blood flow was documented initially (Qb0) and was followed up after 6 (Qb6), 12 (Qb12), and 24 (Qb24) months. Analysis of blood flow and complication rates within the follow-up period was performed by questionnaires. RESULTS: In total, 185 patients were included, of whom 93 received a ST CVTC and 92 a SG CVTC. Baseline parameters did not differ significantly between groups. CVTC blood flow was not significantly different between the two devices. Thrombolytic therapy with Alteplase was used significantly more often in the ST group (29%) than in the SG group (16%) (p < 0.05). The CVTC replacement rate was significantly higher in the ST group (19.3%) compared with the SG group (8.7%) (p < 0.05). CONCLUSIONS: The tip design of CVTC (split or shotgun) appears to be irrelevant for long-term blood flow during dialysis treatment. However, patients may benefit from SG catheters over ST catheters where replacement rates and thrombolytic treatment are concerned.

Laser generated nanoparticles based photovoltaics.

The exploitation of nanoparticles (NP), synthesized via laser ablation in liquids, in photovoltaic devices is reviewed. In particular, the impact of NPs' incorporation into various building blocks within the solar cell architecture on the photovoltaic performance and stability is presented and analysed for the current state of the art photovoltaic technologies.

Germline CDH1 mutations in bilateral lobular carcinoma in situ.

BACKGROUND: Invasive lobular breast cancer (ILC) and lobular carcinoma in situ (LCIS) are characterised by loss of E-cadherin expression. However germline CDH1 mutations are rare in cases of ILC with no family history of hereditary diffuse gastric cancer (HDGC) and have not been described in women with LCIS. METHODS: We screened the CDH1 gene in 50 cases of bilateral LCIS/ILC using Sanger sequencing and MLPA. RESULTS: Sanger sequencing revealed four pathogenic germline mutations, including a novel splicing mutation (c.48+1G>A). The remaining three (c.1465insC, c.1942G>T, c.2398delC) have been previously described. All four cases had bilateral LCIS +/- ILC and no family history of gastric cancer. CONCLUSION: CDH1 germline mutations have not been previously described in women with LCIS. We have shown that germline CDH1 mutations are associated with early onset of bilateral LCIS with or without ILC in women without a family history of gastric cancer. CDH1 mutation screening should be considered in women with early onset of bilateral LCIS/ILC with no family history of HDGC.

[TULC - total umbilical laparoscopic cholecystectomy]. / TULC - Total Umbilikale Laparoskopische Cholezystektomie.

BACKGROUND: Except for some few cases only symptomatic cholecystolithiasis constitutes an indication for operative treatment. The gold standard meanwhile has been the laparoscopic cholecystectomy, because the method shows good results with short hospital stay. Recently there has been an intensive discussion about combination of laparoscopic techniques with natural body orifice using surgery (NOTES). These techniques permit further reduction of surgical trauma and enhancing of cosmetic results. However, the technical effort is significant and most of the times a combination (hybrid procedure) of NOTES with standard laparoscopic procedure is performed, so that we concentrated on performing a laparoscopic cholecystectomy using a single incision through the umbilicus. METHODS: A 5-mm incision left deep in the umbilicus and a 10-mm incision directly below were used for creating a pneumoperitoneum and for inserting the ports for the optic and the dissector. Exposition of the gallbladder was carried out by sutures, that were penetrated from outside through the abdominal wall into the abdominal cavity and transfixed through the gallbladder in order to hang up the gallbladder like a puppet by penetrating the abdominal wall again to the outside. Removal occurred through the umbilical incision. RESULTS: We successfully operated on 90  patients in a 12-month period. Mean operating time was 48 (39-71) min whereby no conversion to open surgery was necessary. No intra- or postoperative complications occurred in any patient. Average hospital stay was 2.5 (2-4) days, postoperative examination showed no differences to the usual laparoscopic cholecystectomy with a good cosmetic result and no visible scars. CONCLUSION: The purpose of our study was to further improve the cosmetic results of minimally invasive surgery of the gallbladder by operating totally through the umbilicus, using 2  ports deep in the umbilicus. We thereby avoid further surgical trauma due to creating an access through another organ as is done in the NOTES technique. For this operation no special equipment like flexible endoscopes was needed as common laparoscopic instruments were used.

High repetition rate pseudospark trigger generator.

We report the design and development of a high repetition rate pseudospark trigger generator for operating pseudospark switches with a low impedance of approximately 50 Omega between the trigger pins. The trigger generator can be operated from a single-shot mode up to a repetition rate of 1 kHz. It produces 3 kV, 1 mus pulses into a 100 Omega load to trigger a single pseudospark gap. Also, with the addition of a self-break spark gap and pulse forming network, the trigger generator can be used to trigger a pseudospark gap with low jitter. In this configuration, it produces 300 ns, 3 kV pulses with rise time of 10 ns. The jitter between trigger pulses applied to the pseudospark is less than 1 ns.

[MR sialography: evaluation of an ultra-fast sequence in consideration of a parallel acquisition technique and different functional conditions in patients with salivary gland diseases]. / MR-Sialographie: Prospektive Evaluation ultraschneller Sequenzen mit paralleler Bildgebung und oraler Stimulation bei Patienten.

PURPOSE: To evaluate an ultra-fast sequence for MR sialography requiring no post-processing and to compare the acquisition technique regarding the effect of oral stimulation with a parallel acquisition technique in patients with salivary gland diseases. MATERIALS AND METHODS: 128 patients with salivary gland disease were prospectively examined using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and a maximum slew rate of 125 mT/m/sec. A single-shot turbo-spin-echo sequence (ss-TSE) with an acquisition time of 2.8 sec was used in transverse and oblique sagittal orientation. All images were obtained with and without a parallel imaging technique. The evaluation of the ductal system of the parotid and submandibular gland was performed using a visual scale of 1-5 for each side. The images were assessed by two independent experienced radiologists. An ANOVA with post-hoc comparisons and an overall two tailed significance level of p = 0.05 was used for the statistical evaluation. An intraclass correlation was computed to evaluate interobserver variability and a correlation of > 0.8 was determined, thereby indicating a high correlation. RESULTS: Depending on the diagnosed diseases and the absence of abruption of the ducts, all parts of excretory ducts were able to be visualized in all patients using the developed technique with an overall rating for all ducts of 2.70 (SD +/- 0.89). A high correlation was achieved between the two observers with an intraclass correlation of 0.73. Oral application of a sialogogum improved the visibility of excretory ducts significantly (p < 0.001). In contrast, the use of a parallel imaging technique led to a significant decrease in image quality (p = 0,011). CONCLUSION: The applied ss-TSE for MR sialography allows fast and sufficient visualization of the excretory ducts of the main salivary glands in patients, and no elaborate post-processing is required. Use of an oral sialogogum is suggested to improve the results of MR sialography.