Surgical reporting for laparoscopic cholecystectomy based on phase annotation by a convolutional neural network (CNN) and the phenomenon of phase flickering: a proof of concept.

PURPOSE: Surgical documentation is an important yet time-consuming necessity in clinical routine. Beside its core function to transmit information about a surgery to other medical professionals, the surgical report has gained even more significance in terms of information extraction for scientific, administrative and judicial application. A possible basis for computer aided reporting is phase detection by convolutional neural networks (CNN). In this article we propose a workflow to generate operative notes based on the output of the TeCNO CNN. METHODS: Video recordings of 15 cholecystectomies were used for inference. The annotation of TeCNO was compared to that of an expert surgeon (HE) and the algorithm based annotation of a scientist (HA). The CNN output then was used to identify aberrance from standard course as basis for the final report. Moreover, we assessed the phenomenon of 'phase flickering' as clusters of incorrectly labeled frames and evaluated its usability. RESULTS: The accordance of the HE and CNN was 79.7% and that of HA and CNN 87.0%. 'Phase flickering' indicated an aberrant course with AUCs of 0.91 and 0.89 in ROC analysis regarding number and extend of concerned frames. Finally, we created operative notes based on a standard text, deviation alerts, and manual completion by the surgeon. CONCLUSION: Computer-aided documentation is a noteworthy use case for phase recognition in standardized surgery. The analysis of phase flickering in a CNN's annotation has the potential of retrieving more information about the course of a particular procedure to complement an automated report.

Simultaneous separation and confirmation of amphetamine and related drugs in equine plasma by non-aqueous capillary-electrophoresis-tandem mass spectrometry.

A non-aqueous capillary electrophoresis-mass spectrometry (NACE-MS) method was developed for simultaneous separation and identification of 12 amphetamine and related compounds in equine plasma. Analytes were recovered from plasma by liquid-liquid extraction using methyl tertiary butyl ether (MTBE). A bare fused-silica capillary was used for separation of the analytes. Addition of sheath liquid to the capillary effluent allowed the detection of the analytes by positive electrospray ionization mass spectrometry using full scan data acquisition. The limit of detection (LOD) for the target analytes was 10-200 ng/mL and that of confirmation (LOC) was 50-1000 ng/mL in equine plasma. Capillary electrophoresis (CE) and mass spectrometry (MS) parameters were optimized for full CE separation and MS detection of the analytes. Separation buffer comprised 25 mM ammonium formate in acetonitrile/methanol (20: 80, v/v) plus 1 M formic acid. Sheath liquid was isopropanol-water-formic acid (50:50:0.5, v/v/v). Samples were hydrodynamically injected and separated at 25 kV. Analytes were electrokinetically separated and mass spectrometrically identified and confirmed. This simple, fast, inexpensive and reproducible method was successfully applied to post race equine plasma and research samples in screening for amphetamine and related drugs.

Cloning and characterization of a family B DNA polymerase from the hyperthermophilic crenarchaeon Pyrobaculum islandicum.

In order to extend the limited knowledge about crenarchaeal DNA polymerases, we cloned a gene encoding a family B DNA polymerase from the hyperthermophilic crenarchaeon Pyrobaculum islandicum. The enzyme shared highest sequence identities with a group of phylogenetically related DNA polymerases, designated B3 DNA polymerases, from members of the kingdom Crenarchaeota, Pyrodictium occultum and Aeropyrum pernix, and several members of the kingdom Euryarchaeota. Six highly conserved regions as well as a DNA-binding motif, indicative of family B DNA polymerases, were identified within the sequence. Furthermore, three highly conserved 3'-5' exonuclease motifs were also found. The gene was expressed in Escherichia coli, and the DNA polymerase was purified to homogeneity by heat treatment and affinity chromatography. Activity staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed an active polypeptide of approximately 90 kDa. For the recombinant DNA polymerase from P. islandicum, activated calf thymus DNA was used as a substrate rather than primed single-stranded DNA. The enzyme was strongly inhibited by monovalent cations and N-ethylmaleimide; it is moderately sensitive to aphidicolin and dideoxyribonucleoside triphosphates. The half-life of the enzyme at 100 and 90 degrees C was 35 min and >5 h, respectively. Interestingly, the pH of the assay buffer had a significant influence on the 3'-5' exonuclease activity of the recombinant enzyme. Under suitable assay conditions for PCR, the enzyme was able to amplify lambda DNA fragments of up to 1,500 bp.

Extremophiles as a source of novel enzymes for industrial application.

Extremophilic microorganisms are adapted to survive in ecological niches such as at high temperatures, extremes of pH, high salt concentrations and high pressure. These microorganisms produce unique biocatalysts that function under extreme conditions comparable to those prevailing in various industrial processes. Some of the enzymes from extremophiles have already been purified and their genes successfully cloned in mesophilic hosts. In this review we will briefly discuss the biotechnological significance of extreme thermophilic (optimal growth 70-80 degrees C) and hyperthermophilic (optimal growth 85-100 degrees C) archaea and bacteria. In particular, we will focus on selected extracellular-polymer-degrading enzymes, such as amylases, pullulanases, cyclodextrin glycosyltransferases, cellulases, xylanases, chitinases, proteinases and other enzymes such as esterases, glucose isomerases, alcohol dehydrogenases and DNA-modifying enzymes with potential use in food, chemical and pharmaceutical industries and in environmental biotechnology.

Postmortem tissue samples: an alternative to urine and blood for drug analysis in racehorses.

Although urine is the sample of choice for drug tests in racehorses, it is rarely obtained following the sudden death of a racehorse on the track while racing. The purpose of this study was to demonstrate the significance of postmortem tissue samples as an alternative to urine and blood samples in equine drug analysis following the sudden death of a racehorse on the track while participating in a competitive race. Postmortem tissue samples were frozen (-80 degrees C) until analyzed. A 30-40-g portion of each organ was homogenized in a 0.1 M phosphate buffer (pH 7.4), deproteinized, hydrolyzed with beta-glucuronidase, extracted, and screened by thin-layer chromatography and immunoassay. Samples that initially tested positive for drug(s) were then extracted using high-flow, solid-phase extraction cartridges. The eluates were analyzed by gas chromatography-mass spectrometry. The presence of butorphanol in horses HB355 and CD387, pentobarbital in horse HO940, and ergotamine in horses HO940 and CD387 was detected and confirmed. Thus, in the absence of urine and blood samples following sudden death, postmortem tissue samples are equally useful for forensic toxicological investigations of racehorses.

Ten years after the Commission on Aging--ideas and results.

During the years 1979-82, the Commission on Aging scrutinised public measures relating to the elderly and recommended adherence to the principles of continuity, self determination and use of own resources in future aging policy. A central point in the Commission's perception of aging was that a number of functional impairments previously considered exclusively a reflection of the biological aging processes were now seen as equally induced by loss of roles and social functions. The renewal of structures and development work carried out throughout the country are based on these principles, integrating social and psychological considerations. Work is also based on the Report on the Public Sector (1988) which recommends enhancement of social networks and self-help capabilities of the old as well as new forms of cooperation between the public sector and citizens. Self determination and self control have become new key words in current aging policy. The new policy is not only induced by financial pressure on the public sector, but equally to the realisation that many social tasks are best solved in cooperation with individuals. The renewal of aging policy is also adapted to the new generations of elderly people, who want freer lifestyles and more options than many of the old have today. They will very likely be more mobile and make more demands for their life. They have been accustomed to creating networks and cross-contacts, as their jobs and interests have required it, and their health and financial circumstances will frequently be better than those of the elderly generation today.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of bromhexine and ambroxol in equine urine: effect of furosemide on identification and confirmation.

The purpose of this study was two-fold: (1) to develop a simple and sensitive screening procedure for identifying and confirming bromhexine and ambroxol and, (2) to determine the effect of furosemide on the detection of bromhexine, ambroxol, or their metabolites in urine. Female horses (450-550 kg) treated with bromhexine or ambroxol (1 g, p.o.) were used. Urine samples were collected up to 48 h post-drug administration and analysed. Blind samples were used in evaluating the sensitivity of these methods and reproducibility of the results. Bromhexine and ambroxol were extensively metabolized in the horse. These agents and their respective metabolites were identified and confirmed using thin-layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS), respectively. Hydroxy-bromhexine and desmethyl-bromhexine were major metabolites found to be unique to bromhexine-treated horses. These metabolites selectively absent from ambroxol-treated horse urine provide a chemical means to distinguish bromhexine from ambroxol administration in horses. These specific metabolites were similarly identified and confirmed in "blind" horse urine samples. The concomitant presence of furosemide (300 mg, i.v.) with bromhexine or ambroxol did not mask the presence of these agents or alter their metabolite profile. By application of the methods described in this study, bromhexine and ambroxol metabolites in horse urine can be easily identified and confirmed.

[Mitochondria number as a prognostic parameter in dilated cardiomyopathy. A long-term follow-up study]. / Die Mitochondrienzahl als prognostischer Parameter bei dilatativer Kardiomyopathie. Eine Langzeitstudie.

According to morphological criteria of the myocardium, patients with clinical and hemodynamic signs of dilated cardiomyopathy were divided into three groups. Group I: patients with 1-2 mitochondria per 2 sarcomeres (n = 46); Group II: patients with more than 2 mitochondria per 2 sarcomeres (n = 47); Group III: patients with histological findings of myocarditis in the past (n = 33). Mean follow-up in groups I, II, III was 29, 22, 26 months, respectively (6-58, 3-52, 3-62/median 29, 18, 22). Clinical parameters were evaluated at the beginning and at the end of the prospective observation and were classified clinically as "improved, unchanged, deteriorated"; "heart transplantation", "death of cardial causes", "death of other than cardial causes" or "lost to follow up" were the other endpoints of the observation. At the beginning there were no hemodynamic differences between groups I, II, III, except significant difference in ejection fraction and mean ventricular shortening velocity between groups I and II. Scored together with the clinical symptoms "deterioration" and "death of cardial causes" as endpoints, survival rates without event up to 5 years in group I were 83 +/- 7% compared with group II 33 +/- 13% and group III 86 +/- 8%. There were significant differences (p less than 0.01). We conclude that the increased number of mitochondria per 2 sarcomeres in biopsy specimen of patients with dilated cardiomyopathy can be a significant parameter of deteriorated prognosis.

New aspects of the kinetics of isoenzyme CK-MB during myocardial infarction: discontinuous release?

Intermittent liberation of the serum marker myoglobin is found in acute myocardial infarction, and the ST segment of the electrocardiogram also shows a phasic rise and fall. We therefore measured the serum marker CK-MB at close intervals of time and recorded an oscillation in the serum level. The peaks are not as high as in the serum myoglobin time curve, and it is not easy to decide if they represent the intermittent liberation of the serum marker. It was possible to distinguish between a "high release" and a "low release" group of patients: the former having a maximum CK-MB value of greater than 100 U/l and the latter of less than 100 U/l. Most patients showed 2-3 "initial peaks" within the first 8 h. The highest of these immediately preceded the climb to the definitive maximum value. We conclude that the small size of the peaks in the CK-MB time curve is due to a different mechanism of enzyme release.

[Randomized study comparing long-chain (LCT) and medium-chain (MCT) triglycerides as caloric carriers in postoperative nutritional therapy]. / Randomisierte Studie zum Vergleich zwischen langkettigen (LCT) und mittelkettigen (MCT) Triglyzeriden als Kalorienträger in der postoperativen Ernährungstherapie.

The aim of the study was to investigate the effect of a new 20% fat emulsion, containing 50% MCT and 50% LCT in comparison to a 20% fat emulsion containing only LCT, in the postoperative period. The possible influence on nitrogen loss, protein synthesis and fat metabolism was estimated. 20 patients after elective colon surgery were included in the trial. Parenteral nutrition was carried out for 5 days with two isonitrogenic and isocaloric nutritional regimens including either MCT/LCT or only LCT fat emulsions. Fat emulsions were administered over a period of 12 h with a total fat supply rate of 0.12 g/kg B.W./h. Blood samples for determination of protein synthesis, triglyceride and ketone bodies were taken under fat infusion as well as before and after infusion. 24-h urine samples were taken to measure nitrogen balance. Our results showed no difference in protein levels between the MCT- and LCT group. The 5-day nitrogen balance showed a significant increase in the MCT group (p less than 0.05, Mann-Whitney U-test). At the end of the infusion period triglyceride levels in the MCT group (mean value 244 +/- 15 mg%) differed significantly compared to the LCT group (m = 190 +/- 24 mg%). 2 h later triglycerides in both groups fell to basal levels. beta-Hydroxybutyrate (beta-HB) and aceto acetate (Ac-ac) concentrations showed significant differences between both groups. After 12 h infusion the MCT group had a mean level of 210 mumol/l beta-HB and 180 mumol/l Ac-ac vs. 90 mumol/l beta-HB and 120 mumol/l Ac-ac in the LCT group.(ABSTRACT TRUNCATED AT 250 WORDS)

Water intoxication in the course of an acute schizophrenic episode.

In the course of a schizophrenic episode a woman drank a large amount of tap water. She was found nearly unconscious in her room and was admitted to the clinic. Very low sodium and potassium values in the serum were indicative of water intoxication. During hospitalization she also suffered from several convulsive seizures. After replacement of electrolytes she recovered within 12 to 17 h. This case report demonstrates that water intoxication should also be considered in cases of suspected poisoning with other substances such as drugs. In all these cases an electrolyte status is indicated.