On the Significance of Systolic Flow Waveform on Aortic Valve Energy Loss

This study aims to quantitatively and qualitatively assess energy dissipation in the aortic valve as a function of systolic aortic flow waveform representing pathologies where flow time-to-peak is delayed. A bioprosthetic valve was tested in the aortic position of a left-heart simulator under physiological pressure and flow conditions. The flow loop piston pump was programmed to generate three different flow waveforms each with a different peak time annotated as early peak (EP) with a rapid acceleration, mid peak (MP) and late peak (LP) with a rapid deceleration. Energy dissipation was calculated from flow and pressure measurements while sinus vorticity dynamics were evaluated using time-resolved planar particle image velocimetry. Average pressure gradients during systole are found 30.2?±?0.19, 30.7?±?0.25 and 32.9?±?0.29 mmHg and average dissipation over systole is found 0.95?±?0.026, 1.05?±?0.034 and 1.25?±?0.043 W for EP, MP and LP respectively. As systole’s acceleration phase is slower, sinus vortices are more likely to form, necessitating more energy exchange from shear layers inducing more viscous dissipation. EP found in healthy individuals is superior in terms of reducing energy dissipation and increasing aortic valve efficiency. In the context of possible left ventricular dysfunction and aortic stenosis, this means that delayed time-to-peak in the aortic flow waveform seen is not compensatory.     

Effects of Pyriproxyfen on Intermediary Metabolism of Rice Striped Stem Borer, <Emphasis Type="Italic">Chilo suppressalis</Emphasis> Walker (Lepidoptera: Crambidae)

Effects of Pyriproxyfen were determined on intermediary metabolism in the fifth larval instars of Chilo suppressalis via assessments of various enzymatic and non-enzymatic compounds. Bioassay of larvae revealed LC_10–50 values of 18, 72 and 190 µg/ml of pyriproxyfen. Results on alanine aminotransferase revealed lower activities in treated larvae versus control for all time intervals while activity of aspartate aminotransferase showed higher activities in treated larvae by 18 and 72 µg/ml of pyriproxyfen. Activities of γ-Glutamyl transferase and aldolase in treated larvae were significantly higher than those of control larvae. Treating of larvae by different concentrations of pyriproxyfen significantly increased lactate dehydrogenase activity for all time intervals although activity of the enzyme after 1 h was not significantly different among control and treated larvae. Activities of acid and alkaline phosphatases in treated larvae were higher than those of control. Amount of high and low density lipoproteins in treated larvae was higher than those of control except for time interval of 3 h of HDL in which control larvae revealed higher amount than 72 and 190 µg/ml treated larvae. Increased activity of the enzyme was noticed in treated larvae versus control in case of general esterases. Similar results were observed in case of glutathione S-transferase. Amount of triacylglyceride, glycogen and protein in control larvae was higher than those of treated larvae for all time intervals indicating their depletion due to energetic costs of pyriproxyfen treatment. These results clearly indicated negative effects of pyriproxyfen on intermediary metabolism of larvae that might lead to desirable mortality in pest population.     

The evidence for and against different modes of tumour cell extravasation in the lung: diapedesis,capillary destruction,necroptosis, and endothelialization

The development of lung metastasis is a significant negative prognostic factor for cancer patients. The extravasation phase of lung metastasis involves interactions of tumour cells with the pulmonary endothelium. These interactions may have broad biological and medical significance, with potential clinical implications ranging from the discovery of lung metastasis biomarkers to the identification of targets for intervention in preventing lung metastases. Because of the potential significance, the mechanisms of tumour cell extravasation require cautious, systematic studies. Here, we discuss the literature pertaining to the proposed mechanisms of extravasation and critically compare a recently proposed mechanism (tumour cell‐induced endothelial necroptosis) with the already described extravasation mechanisms in the lung. We also provide novel data that may help to explain the underlying physiological basis for endothelialization as a mechanism of tumour cell extravasation in the lung. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Behandlung der Belastungsinkontinenz nach radikaler Prostatektomie

Background

The adjustable transobturator male system (ATOMS?) is a new method for the treatment of male stress urinary incontinence. This article presents the results of a prospective multicenter observational study with this system.

Patients and methods

Between March 2009 and March 2011 a total of 124 patients with persistent stress urinary incontinence after radical prostatectomy received the ATOMS system. Postoperative adjustments via the implanted port chamber were performed after 6 weeks and thereafter when necessary. Postoperative evaluation consisted of medical history, mictionary protocol, 24-h pad tests, 24-h pad counts and sonography.

Results

The mean age of the patients was 71.2±5.5 years (range 58-85 years). Previous incontinence surgery had been carried out in 36.3% of patients while 34.5% of patients had a previous history of radiation treatment. The mean operation time was 48.3±11.2?min (range 36-116?min) and the mean hospital stay was 3.8±1.2 days (range 2-6 days). No intraoperative urethral or bladder injuries occurred. After removal of the transurethral catheter on the first postoperative day, temporary urinary retention occurred in 3 patients who were conservatively treated. Transient perineal/scrotal pain or dysesthesia was observed in 75 patients (60.5%) and resolved after 3-4 weeks of non-opioid analgesics. There were no perineal infections; however, infections at the port site occurred in 3 patients (2.4%) leading to explantation of the system in all cases. The average number of adjustments to achieve the desired result was 4.3±1.8 (range 2-7). After a mean follow-up of 19.1±2.2 months (range 12-36 months), there was a significant reduction in the mean number of pads/24?h from 8.8 to 1.8 (p<0.001). The overall success rate was 93.8% with 61.6% of the patients being dry and 32.2% of the patients showing improvement.

Conclusions

The results of the study demonstrate the safety and efficacy to date of the ATOMS system for treatment of stress urinary incontinence after radical prostatectomy.     

Nephrektomie – pro laparoskopisch

Laparoscopic radical nephrectomy (LRN) is considered as a standard of care for T2 renal masses and T1 tumors not treatable by nephron-sparing surgery. It can be performed transperitoneally, retroperitoneoscopic or hand-assisted. However, the morbidity after laparoscopic nephrectomy has been shown to be lower than the open procedure and patients seem to benefit from early mobilization, less pain medication, shorter hospital stays and an earlier return to normal daily activities. Furthermore, the extent of perioperative activation of the systemic stress response appears to be less during laparoscopic procedures. This has been shown to have evidently beneficial clinical impact on patient's recovery; however, its importance for the oncologic prognosis is somewhat unclear. In addition, the progression-free and overall tumor-specific survival rates for laparoscopic nephrectomy are equivalent to those for open surgery. The experiences with robot-assistance for laparoscopic nephrectomy reported so far show no significant advantages over traditional laparoscopic nephrectomy. However, the problem of high costs of acquisition and operation of robots still remains unsolved. For the future, prospective studies are needed in order to compare the functional and oncological outcomes and cost-effectiveness of different methods of radical nephrectomy.     

Minimization of cytogenetic toxicity of malathion by vitamin C.

Genotoxic effect of agriculture-used concentration of organophosphorous pesticide, Malathion, is decreased by the dietary concentration of sodium salt of L-ascorbic acid for parameters like mitotic-index and clastogeny in onion root-tip cells, clastogeny and meiotic-index in mice, and lethal mutation rate in Drosophila melanogaster. The vitamin itself is not genotoxic, and its concurrent administration is more effective than pretreatment with it. Possible mechanism of such vitamin C-mediated minimization of pesticide-genotoxicity is discussed.     

The CarboMedics®"Top Hat" Supraannular Prosthesis in the Small Aortic Root

Twenty-three patients, 11 men and 12 women, with a mean age of 64 (range, 34 to 78) underwent aortic valve replacement (AVR) with a CarboMedics®“Top Hat” supraannular prosthesis between March 1993 and August 1994. The top hat supraannular prosthesis, a standard bileaflet valve with the cuff transferred to the valve inflow level, allowed implantation of 21-mm, 23-mm, and 25-mm valves, where a standard 19-mm or 21-mm valve would have usually been placed. One patient who had been in preoperative cardiogenic shock died in the perioperative period. Another had an intraoperative cerebral embolism with permanent impairment. Follow-up on 22 of 23 patients over a mean period of 9 months revealed mean Doppler gradients of 18 ± 6 mmHg, 15 ± 2.8 mmHg, and 11 mmHg, for the 21-mm, 23-mm, and 25-mm valves, respectively. Functional improvement was noted, with 17 patients in New York Heart Association (NYHA) Class I and 6 in NYHA Class II, postoperatively, compared with 0 in Class I, 9 in Class II, 10 in Class III, and 4 in Class IV, preoperatively. One patient showed reduced postoperative ventricular function with fractional shortening below 25%. Pandiastolic regurgitation intrinsic to the valve graded as slight was noted in all patients. Other postoperative complications included one patient with anticoagulant-related gastrointestinal bleeding and one other with prosthetic valve endocarditis successfully treated with antibiotics. The CarboMedics® top hat valve allows a gain in prosthesis size of 2 mm to 4 mm in the aortic position over standard prostheses, resulting in favorable postoperative hemodynamics.