Endoscopic projection of the gastroduodenal artery: Anatomical implications for bleeding management.

INTRODUCTION: Peptic ulcers account for 50% of upper gastrointestinal bleeding incidents. Bleedings from large vessels, such as the gastroduodenal artery, are associated with increased mortality. Ulcers located on the posterior wall of the duodenum show the highest risk for erosion of the gastroduodenal artery. Endoscopic management is challenging and rebleeding rates are high due to internal and external confounding factors such as anatomical variability and gastric insufflation. We aimed to correlate macroscopic and endoscopic anatomy for assessment of implications for clinical management. MATERIAL AND METHODS: The gastroduodenal artery was dissected in 10 anatomical specimens. The points of contact of the artery with the posterior wall of the duodenum were marked with needles. The endoluminal position of the needles was recorded by standardized gastroscopy and a 3-dimensional virtual reconstruction was carried out for visualization of the artery's course. RESULTS: The artery's proximal and distal points of contact with the duodenum were 27.2mm (range 15-30mm; SD 6.7mm) and 15mm (range 10-20mm; SD 3.5mm), respectively, from the pylorus. The gastroduodenal artery branches from the common hepatic artery within the omentum minus running adjacent to the duodenal wall to the head of the pancreas. From endoscopic perspective, the gastroduodenal artery's course was directed towards the tip of the gastroscope. CONCLUSION: Due to the peculiar extraluminal course of the gastroduodenal artery the arterial blood flow projects into the direction of the gastroscope during endoscopic intervention. Measures for bleeding control might have to be applied aboral from the bleeding site.

How to manage patients in whom malignancy and infective endocarditis are associated: a review.

Objective. Infective endocarditis (IE) is a potentially short-term lethal condition. An association with malignancy could complicate diagnostic and therapeutic decisions. The questions to be answered are: (1) which type of malignancies are encountered; (2) how often has the association between malignancy and IE been described, and (3) what are thus far the diagnostic and treatment strategies for patients with both conditions. Methods. A literature search from 2010 to 2018 has been performed with the focus on IE and cancer/malignancy/neoplasm, as well as with risk factors for adverse outcome, when cancer was included in the analysis. Results. An association between digestive, respiratory and hematologic malignancy with IE has been observed in four large databases. The most important mechanisms for this association are a "port of entry" and immune suppression. Sixteen studies dealt with the effect of short and mid-term cancer on the outcome of surgery of IE in these patients. No uniform management strategy could be identified. It seems that a malignancy does not alter the short-term outcome for IE, although referral to a tertiary cardiac center and surgical treatment are less common for patients with known malignancy. Conclusions. Although there is an association between malignancy and IE, no treatment strategy has yet been developed for these patients. Short-term outcome of IE is unaltered by cancer. In most papers, the effect of cancer on mid-term survival is only significant in a univariate analysis, without being a predictor. The results indicate that cardiac surgery for IE should not be withheld in patients in whom a treatable malignancy has been found.

Ultrafast Single-Molecule Fluorescence Measured by Femtosecond Double-Pulse Excitation Photon Antibunching.

Most measurements of fluorescence lifetimes on the single-molecule level are carried out using avalanche photon diodes (APDs). These single-photon counters are inherently slow, and their response shows a strong dependence on photon energy, which can make reconvolution of the instrument response function (IRF) challenging. An ultrafast time resolution in single-molecule fluorescence is crucial, e.g., in determining donor lifetimes in donor-acceptor couples which undergo energy transfer, or in plasmonic antenna structures, where the radiative rate and non-radiative rates are enhanced. We introduce a femtosecond double-excitation (FeDEx) photon correlation technique, which measures the degree of photon antibunching as a function of time delay between two excitation pulses. In this boxcar integration, the time resolution of fluorescence transients is limited solely by the laser pulse length and is independent of the detector IRF. The versatility of the technique is demonstrated with a custom-made donor-acceptor complex with one donor and two acceptors and with single dye molecules positioned accurately between two gold nanoparticles using DNA origami. The latter structures show ∼75-fold radiative-rate enhancement and fluorescence lifetimes down to 19 ps, which is measured without the need for any reconvolution. With the potential of measuring subpicosecond fluorescence lifetimes, plasmonic antenna structures can now be optimized further.

Anomalous Linear Dichroism in Bent Chromophores of π-conjugated Polymers: Departure from the Franck-Condon Principle.

We examine the influence of bending of π-conjugated chromophores on photoluminescence (PL) by spectrally resolving the depolarization of fluorescence on the single-molecule level. The effect of excited-state mixing mediated by molecular vibrations is manifested in the departure from the usual achromatic linear dichroism of fluorescence, with the polarization anisotropy decreasing in the vibronic progression. Bent chromophores reveal an overall increase in vibronic PL intensity with polarization orthogonal to the molecular long axis. This manifestation of the Renner-Herzberg-Teller (RHT) effect illustrates the breakdown of the Franck-Condon principle in macromolecules used in organic electronics, providing information on the orientation of transition-dipole moments and the origin of spectral broadening. While some of the spectral signatures of the RHT effect appear similar to those of H aggregation in molecular dimers, discrimination between the two phenomena is straightforward since H aggregation does not induce anomalous linear dichroism.

Hypertriglyceridaemia and the risk of pancreatitis six months post lopinavir/ritonavir initiation.

BACKGROUND: Hypertriglyceridaemia (HTG) is an important risk factor for pancreatitis and cardiovascular disease (CVD), depending on severity. Hypertriglyceridaemia is common in human immunodeficiency virus (HIV) infection and is also a common complication of lopinavir/ritonavir (LPV/r). OBJECTIVES: To evaluate the risk of pancreatitis associated with HTG in patients six months post initiation of LPV/r-based therapy in a regional public hospital. METHODS: Triglyceride (TG), serum amylase (s-amylase) and CD4+ count values were retrospectively investigated six months post LPV/r-based initiation. Age, gender, previous antiretroviral regimen and period since HIV diagnosis were also recorded. RESULTS: The final sample consisted of 194 patients, 50 males and 144 females; mean (± standard deviation [s.d.]) age was 39.52 (± 9.98) years, and the mean (± s.d.) period since HIV diagnosis was 91.32 (± 25.18) months. Normal TG levels (< 1.70 mmol/L) were detected in only 55% of patients and the rest presented with some degree of HTG. The mean (± s.d.) TG for the entire sample was elevated at 1.94 (± 1.30) mmol/L with the mean (± s.d.) of the males at 2.36 (± 1.74) - statistically higher compared to the females at 1.79 (± 1.08) mmol/L (p = 0.034). No cases of pancreatitis were recorded and the time since HIV diagnosis did not indicate any statistically significant differences in the means of the TG, serum amylase or CD4 count values. CONCLUSION: Triglyceride levels were not substantially elevated to induce pancreatitis at six months post initiation of LPV/r, but were elevated above the accepted upper normal limit of 1.70 mmol/L which may have implications for cardiovascular risk.

What are the main predictors of in-hospital mortality in patients with infective endocarditis: a review.

OBJECTIVES: Infective endocarditis (IE) has a high 30-day mortality. Surgery is needed in many patients. The preoperative hemodynamic status (congestive heart failure, need for urgent/emergent surgery or mechanical support, NYHA class III/IV) could have an impact on postoperative outcome. Each of these parameters is an indication for the inadequacy of the left ventricle to maintain an adequate circulation Methods. A literature search was performed using "endocarditis AND hospital mortality OR outcome AND predictor" and "International Collaboration on Endocarditis - Prospective Cohort Study" in Web of Science database, from 2010-2017. The focus was hospital mortality and its predictors. Manuscripts were excluded if no logistic regression or propensity analysis was available. The predictors were ranked according the odds ratios. Articles with risk scores based on multivariate analysis were also added. RESULTS: Most studies are coming from one tertiary center and are retrospective, with different designs. Recruitment periods are long and sample sizes small. Definitions of preoperative events such as hemodynamic status are not uniform. Thirty-day mortality varies between 10 and 50%. In 8 of 18 papers where the hemodynamic status is included, it is ranked as first and in 3 as second. The scoring systems confirm in several occasions the importance of left ventricular factors. DISCUSSION: The heterogeneity of the included papers and lack of uniform definitions of preoperative events precludes a proper meta-analysis. Nevertheless, heart failure and a compromised hemodynamic status can be identified as the dominant predictor for 30-day mortality of IE. This seems avoidable by early surgery.

The cryogenic storage ring CSR.

An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm(-3) is derived, equivalent to a room-temperature pressure below 10(-14) mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

Pure Natural Orifice Transluminal Endoscopic Surgery (NOTES) with a new elongated, curved Transanal Endoscopic Operation (TEO) device for rectosigmoid resection: a survival study in a porcine model.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) has seen considerable new developments in its evolution to a platform for rectal and sigmoid resection, but to date no true single NOTES procedure has been convincing. This study investigates the safety and feasibility of a further developed transanal NOTES platform for single-access NOTES rectosigmoid resection. METHODS: Ten large female pigs, mean weight 99.3 kg [standard deviation (SD) 7 kg, range 85.1-112.6 kg], underwent transanal rectosigmoid resection. Five animals were included in an acute study group with immediate postoperative euthanization. A second group included five animals in a survival study. Transanal rectosigmoid resections were performed with an elongated and curved transanal endoscopic operation (TEO) device. Coloanal anastomosis was performed using the transanal circular stapler technique. Survival follow-up was at 7 and 28 days via colonoscopy under sedation. RESULTS: Single-access NOTES transanal rectosigmoid resection with coloanal anastomosis was performed in nine out of ten female pigs. Mean length of rectosigmoid specimens exteriorized was 18.7 cm (SD 2.9 cm, range 14-23 cm). Mean operating time was 124 min (SD 35.7 min, range 70-166 min). Within the survival group, no complications occurred during the monitoring phase. In one case, there was ascites and colitis at necropsy as well as fibrosis at the anastomosis site. CONCLUSIONS: Pure transanal rectosigmoid resection is a feasible procedure. The approach via a single transanal access is demanding but viable with the elongated and curved TEO device. The newly developed scope offers an excellent view of the area cephalad to the promontory.

Use of self-retaining barbed suture for rectal wall closure in transanal endoscopic microsurgery.

BACKGROUND: The aim of this study was to investigate the safety and efficacy of self-retaining barbed sutures in comparison with monofilament clip-fixated sutures for rectal wall closure in transanal endoscopic microsurgery. METHODS: Horizontal full-thickness wall defects (3.5 cm) of cattle rectal specimens were closed via transanal endoscopic microsurgery using a monofilament suture with clips at the end (Surgipro(®) 2/0; Covidien, Mansfield, MA, USA, n = 25) or a self-retaining barbed suture (V-Loc™ 180 3/0; Covidien, Mansfield, MA, USA, n = 25). The primary endpoint was the pneumatic leakage pressure of the suture line. As a secondary endpoint, suture time was evaluated. RESULTS: The median pneumatic leakage pressure for barbed sutures was 45.5 mbar (range 17-106 mbar) and 33.5 mbar (range 19-106 mbar) for monofilament sutures (p = 0.58). A pneumatic leak at a critical pressure below 25 mbar occurred in 3 cases with barbed sutures and in 7 cases with monofilament sutures (p = 0.29). Median suturing time [19:25 min:s (range 12:00-33:30) vs. 20:41 (17:00-28:33), p = 0.23] did not differ between the two groups. CONCLUSIONS: Barbed sutures display the same bursting pressure as monofilament sutures and their use for rectal wall closure seems feasible.

Cancer in heart disease patients: what are the limitations in the treatment strategy?

Cardiovascular disease and cancer are leading causes of morbidity and mortality, and can both be present in one patient. In patients with simultaneous disease, the most threatening disease should be treated first. This is usually heart disease, but this can pose specific problems. If percutaneous coronary intervention is preferred, bleeding and thrombotic tendencies have to be taken into account in the subsequent treatment of the malignancy. With coronary artery bypass grafting, the advantages and disadvantages of one- or two-stage procedures, and the use of extracorporeal circulation have to be balanced. Development of heart disease after treatment of malignancy could be due to radiotherapy and chemotherapy. The effects of these cancer treatments have to be taken into account for the treatment options of the heart disease and the postoperative prognosis.

An unusual case of aortic valve obstruction.

During a dissection class for anatomy, a white lipoid mass was found in the ascending aorta, which was partly attached to the wall and filled the sinuses ofValsalva and almost fitting as a cast. This mass prevented full opening of the mobile aortic valve leaflets, thereby causing an obstruction. Microscopic analysis revealed fibres and presence of polymorphonuclear white blood cells. It seems reasonable to assume that this mass has formed in the last weeks or months of the life of this subject, which is much quicker than for calcified aortic valve stenosis. Therefore, signs and symptoms of aortic obstruction might have been missed or misinterpreted. In case of timely detection during life, diagnostic imaging and therapeutic approach can be challenging.

[The effect of energy drinks on the cognitive performance of adolescents]. / Geen effect van energiedrank op de cognitieve prestaties van jongeren.

BACKGROUND: Manufacturers of energy drinks claim that their drinks can have a positive effect on cognitive performance. So far, there is little evidence that energy drinks do in fact enhance the cognitive performance of adolescents. AIM: To find out, via a series of tests, whether the manufacturers of energy drinks are justified in claiming that their drinks improve the cognitive performance of young people. METHOD: In a quasi-experimental design a number of young people (aged 15-18) were divided into three groups: a control group, each of whose members drank water beforehand; a placebo group whose members drank a glass of sugar-free lemonade, and an experimental group whose members drank a currently available energy drink (Megaforce). Pencil and paper tests were administered to the members of each group in order to measure attention and concentration, learning ability, memory, verbal and numerical reasoning, numerical aptitude and vocabulary. RESULTS: No significant differences between groups were found that could solely be ascribed to the effect of energy drink. CONCLUSION: Given the warnings about the potential health-risks of energy drinks and the fact that no evidence was found for positive effects of energy drinks on the cognitive performance of young people, we are of the opinion that youngsters should stay away from such drinks.

Technical complications during removal of locking screws from locking compression plates: a prospective multicenter study.

PURPOSE: To assess the risk for technical complications in patients undergoing removal of locking compression plates (LCP) with head locking screws. METHODS: A total of 205 patients who were scheduled for implant removal surgery after a healed fracture of the femur, tibia, humerus, distal radius, or clavicle in nine Austrian clinics were prospectively included in the study, all of whom had previously undergone fracture fixation by plates, with titanium implants used in 98 % of the patients. Intraoperative technical complications and the methods used to solve them were documented by the surgeon. RESULTS: During the course of this study, a total of 1,462 locking screws were removed from 204 LCPs. While 95 % of these screws could be removed without difficulties, technical complications were reported for 41 patients with 78 screws which could not be removed with standard screwdrivers and required the use of additional instruments. The estimated risk for the occurrence of at least one technical complication during implant removal surgery was 20.1 %. The most frequently observed complications were screws that could not be loosened because they were jammed in the LCP, screws with a damaged recess in which the screwdriver turned freely, as well as a combination of both events. The majority of these screws could be removed with the use of a conical extraction screw or by drilling off the screw head. In one patient, an intraoperative refracture of the humerus occurred during plate removal. Even though there is a rate of 20 % for technical complications when removing the implants, only a few patients experience a clinical impact. CONCLUSIONS: Titanium LCPs are prone to technical complications during implant removal, but the majority of the issues can be solved using special techniques.

Formation of liquid and solid products from liquid phase pyrolysis.

The aim of the present work was to improve the C:O ratio in biomass by preserving the lignin macrostructure of lignocellulosic feed. The intention of liquid phase pyrolysis is to liquefy biomass and prepare biomass for further upgrading steps like hydrogenation and deoxygenation. Pyrolysis was carried out in a non-aqueous liquid phase heat carrier. The process was carried out in a semi-batch reaction vessel under isothermal conditions at T=350°C, supported by a quench to stop reactions instantaneously in order to observe formation of solid intermediates. This pyrolysis system enables the observation of liquid and solid product formation. Transformation of biomass into biochar was analyzed by infrared spectroscopy and elemental analysis. Stable lignin structure throughout the whole transformation was confirmed. It was shown that the lignin frame in wood remains without substantial loss, while the major amount of carbohydrates is pyrolyzed during liquid phase pyrolysis at T=350°C.

Effect of verbal encoding and motor memory on test performance in the Rey Visual Design Learning Test.

This study offers new evidence for the validity of the interpretation of the Rey Visual Design Learning Test (RVDLT) test score. The RVDLT is a design memory test that requires constructive output (drawings of memorized test items) in the recall phase. We mainly focused on response processes and tested the effect of a verbal and a motor memory strategy on test performance. Strategies were only explained and participants (12- to 15-year-olds) were stimulated to use them in a subsequent test session. In the verbal encoding condition, participants were instructed to name the test items of the RVDLT. In the copy condition, participants copied test items with an empty pen concurrent with test item presentation (rehearsal of motor sequences). Test performances were compared to a control group. No significant difference in RVDLT test score was detected between the verbal encoding group and the control group. However, the copy group scored significantly lower than the other two groups. Results are discussed in light of the validity of the test interpretation.

Validity of the Rey Visual Design Learning Test in primary and secondary school children.

The Rey Visual Design Learning Test (Rey, 1964, cited in Spreen & Strauss, 1991, Wilhelm, 2004) assesses immediate memory span, new learning, delayed recall and recognition for nonverbal material. Two studies are presented that focused on the construct validity of the RVDLT in primary and secondary school children. In the first study, primary school children performed the RVDLT and the Biber Figural Learning Test, as well as the WISC-R Block design Test, Boston Naming Test, and the Trailmaking Test, to assess discriminant validity. In the second study, the age range was expanded and the subtest Visual Reproductions of the Wechsler Memory Scale with a Delayed recall phase was used to assess the construct validity. A test for visual-motor integration and a test for attention, concentration, and speed of information processing were also added to complete the test battery for assessing discriminant validity. Moderate to high correlations were found between scores on the RVDLT and the tests used to assess construct validity. The correlational pattern of RVDLT scores and the scores on the discriminant tests is discussed.