[Older patients in abdominal surgery]. / Ältere PatientInnen in der Viszeralchirurgie.

BACKGROUND: The aging society imposes special challenges on operative medicine. OBJECTIVE: Characteristics in the perioperative treatment of older patients. Consequences for the daily practice. MATERIAL AND METHODS: Evaluation and summary of existing literature including recommendations for the (peri)operative management of older patients. RESULTS: Despite the growing relevance there are only few studies focusing on older patients. The altered (patho)physiology and comorbidities are challenging and can lead to complications. CONCLUSION: The evaluation of the indications for surgery should meticulously take the improvement to be expected into account by weighing up the individual wishes of patients and special risks. The adequate perioperative care including early mobilization and sufficient analgesia are decisive.

Hospital volume following major surgery for gastric cancer determines in-hospital mortality rate and failure to rescue: a nation-wide study based on German billing data (2009-2017).

BACKGROUND: For many cancer resections, a hospital volume-outcome relationship exists. The data regarding gastric cancer resection-especially in the western hemisphere-are ambiguous. This study analyzes the impact of gastric cancer surgery caseload per hospital on postoperative mortality and failure to rescue in Germany. METHODS: All patients diagnosed with gastric cancer from 2009 to 2017 who underwent gastric resection were identified from nation-wide administrative data. Hospitals were grouped into five equal caseload quintiles (I-V in ascending caseload order). Postoperative deaths and failure to rescue were determined. RESULTS: Forty-six thousand one hundred eighty-seven patients were identified. There was a significant shift from partial resections in low-volume hospitals to more extended resections in high-volume centers. The overall in-house mortality rate was 6.2%. The crude in-hospital mortality rate ranged from 7.9% in quintile I to 4.4% in quintile V, with a significant trend between volume categories (p < 0.001). In the multivariable logistic regression analysis, quintile V hospitals (average of 29 interventions/year) had a risk-adjusted odds ratio of 0.50 (95% CI 0.39-0.65), compared to the baseline in-house mortality rate in quintile I (on average 1.5 interventions/year) (p < 0.001). In an analysis only evaluating hospitals with more than 30 resections per year mortality dropped below 4%. The overall postoperative complication rate was comparable between different volume quintiles, but failure to rescue (FtR) decreased significantly with increasing caseload. CONCLUSION: Patients who had gastric cancer surgery in hospitals with higher volume had better outcomes and a reduced failure to rescue rates for severe complications.

Mild dehydrated hereditary stomatocytosis revealed by marked hepatosiderosis.

We report a patient in whom hepatosiderosis was diagnosed at the age of 55 years and who has since been treated by regular bleeding. The H63D mutation was found in the heterozygous state in the HFE gene. No mutation was recorded in the SLC11A3 gene (ferroportin). Hepatosiderosis did not seem primary, nevertheless its cause long remained elusive. Only 2 years ago did we find the responsible condition, a very mildly expressed form of dehydrated hereditary stomatocytosis (DHS). This genetic disease is a strongly iron-loading condition. Haemolysis was fully compensated. Kalaemia was slightly elevated, suggesting a pseudohyperkalaemia that may be associated with DHS. Osmotic gradient ektacytometry allowed to assess the diagnosis of DHS. The red cell monovalent Na+ and K+ concentrations were moderately elevated and reduced respectively. The temperature dependence of the ouabain + bumetanide-resistant K+ influx produced a shallow slope, above and parallel to the control curve. These features were consistent with the diagnosis of DHS. The pronounced hepatosiderosis contrasted with the mildly expressed DHS, and with the ferritinaemia that was slightly elevated, if at all, prior to bleeding. Bleeding caused ferritinaemia to decrease and hepatosiderosis to recede. The whole picture accounts for a misleading presentation of DHS, in which the primary condition long remained hidden behind one of its remotest complications, hepatosiderosis.

Effective biasing schemes for duct streaming problems.

The effective use of biasing for the Monte Carlo solution of a void streaming problem is essential to obtaining a reasonable result in a reasonable amount of time. Most general purpose Monte Carlo shielding codes allow for the user to select the particular biasing techniques best oriented to the particular problem of interest. The biasing strategy for void streaming problems many times differs from that of a deep penetration problem. The key in void streaming is to bias particles into the streaming path, whereas in deep penetration problems the biasing is aimed at forcing particles through the shield. Until recently, the biasing scheme in the SCALE SAS4 shielding module was considered inadequate for void streaming problems due to the assumed one-dimensional nature of the automated bias prescription. A modified approach to the automated biasing in SAS4 has allowed for significant gains to be realised in the use of the code for void streaming problems. This paper applies the modified SAS4 procedures to a spent fuel storage cask model with vent ports. The results of the SAS4 analysis are compared with those of the ADVANTG methodology, which is an accelerated version of MCNP. Various options available for the implementation of the SAS4 methodology are reviewed and recommendations offered.

Mortality from all cancers of asbestos factory workers in east London 1933-80.

OBJECTIVE: To give the observed and expected deaths due to cancer at all separate sites in asbestos workers in east London, and to analyse these for overall effect and exposure-response trend. METHODS: The mortality experience of a cohort of over 5000 men and women followed up for over 30 years since first exposure to asbestos has been extracted. RESULTS: There was a large excess of deaths due to cancer (537 observed, 222 expected). Most of these were due to cancer of the lung (232 observed, 77 expected) and pleural (52) and peritoneal (48) mesothelioma. The exposure-response trend for all these three causes was highly significant. There was also an excess of cancer of the colon (27 observed, 15 expected) which was significantly related to exposure. There were significant excesses of cancer of the ovary, of the liver, and of the oesophagus but with no consistent relation to exposure. CONCLUSIONS: The excess risk of cancer after exposure to asbestos was mainly due to cancer of the lung and mesothelioma. An exposure related excess of cancer of the colon was also detected but the possibility that some of these deaths may have been peritoneal mesotheliomas could not be excluded. There was no consistent evidence of exposure related excesses at any other site.

Natural language generation of surgical procedures.

A number of compositional Medical Concept Representation systems are being developed. Although these provide for a detailed conceptual representation of the underlying information, they have to be translated back to natural language for used by end-users and applications. The GALEN programme has been developing one such representation and we report here on a tool developed to generate natural language phrases from the GALEN conceptual representations. This tool can be adapted to different source modelling schemes and to different destination languages or sublanguages of a domain. It is based on a multilingual approach to natural language generation, realised through a clean separation of the domain model from the linguistic model and their link by well defined structures. Specific knowledge structures and operations have been developed for bridging between the modelling 'style' of the conceptual representation and natural language. Using the example of the scheme developed for modelling surgical operative procedures within the GALEN-IN-USE project, we show how the generator is adapted to such a scheme. The basic characteristics of the surgical procedures scheme are presented together with the basic principles of the generation tool. Using worked examples, we discuss the transformation operations which change the initial source representation into a form which can more directly be translated to a given natural language. In particular, the linguistic knowledge which has to be introduced--such as definitions of concepts and relationships is described. We explain the overall generator strategy and how particular transformation operations are triggered by language-dependent and conceptual parameters. Results are shown for generated French phrases corresponding to surgical procedures from the urology domain.

Natural language generation of surgical procedures.

The GALEN-IN-USE project has developed a compositional scheme for the conceptual representation of surgical operative procedure rubrics. The complex representations which result are translated back to surface language by a tool for multilingual natural language generation. This generator can be adapted to the specific characteristics of the scheme by introducing particular definitions of concepts and relationships. We discuss how the generator uses such definitions to bridge between the modelling 'style' of the GALEN scheme and natural language.

Evaluation of hepatitis C virus envelope proteins expressed in E. coli and insect cells for use as tools for antibody screening.

BACKGROUND/METHODS: The two envelope proteins of hepatitis C virus, E1 and E2, were expressed in E. coli and, as secretory proteins, in Sf9 insect cells using recombinant baculoviruses. Co-infection of insect cells with E1 and E2-recombinant baculoviruses was performed, which has been shown to result in formation of E1-E2 dimers. All envelope proteins were purified by Ni2+-NTA chromatography and used for screening of serum samples in a HCV EIA assay. Serum samples of normal blood donors, chronically HCV-infected patients, a mixed titer panel and several seroconversion panels were screened and compared to test results with Cobas Core Anti-HCV EIA. RESULTS: Screening of the sera of chronically HCV-infected patients (100% positive in Cobas Core Anti-HCV EIA) revealed 10-40% anti-E1 positive sera using different Sf9-expressed, glycosylated proteins and 93% using E. coli-expressed, non-glycosylated E1 protein. When the same sera were tested with different E2 proteins expressed in Sf9 cells and in E. coli, about 70-73% showed anti-E2 reactivity. When the proteins from Sf9 cells co-infected with E1- and E2-recombinant baculoviruses were tested, 70-80% of the same sera showed anti-envelope reactivity. CONCLUSIONS: Testing of these patient antisera, and those from the well-characterized mixed titer panel BBI-PHV203, showed that recombinant E1 expressed in E. coli and co-expressed E1 and E2 proteins from Sf9 cells could be used as additional tools for anti-HCV antibody screening.

Anabolic steroid use among adolescents in Nebraska schools.

The extent of anabolic steroid use among adolescent sports participants and nonparticipants in Nebraska schools was studied. The Nebraska Secondary School Survey administered in 1991 contained 19 new items designed to determine rates of use of anabolic steroids and to measure participation in school sports. Schools participating in the survey are part of the Toward a Drug Free Nebraska training project; when the 1991 survey was conducted, training did not address ergogenic drug use. The survey was administered on a voluntary and confidential basis to Nebraska students in grades 7 through 12. A total of 4722 students in 62 secondary schools were surveyed; 3183 (67.4%) identified themselves as participants in school-sponsored sports. Of all the respondents, 117 (2.5%) reported having used anabolic steroids in the preceding 30 days. Some 4.5% of all the male respondents were steroid users, versus 0.8% of all the females. Of the students who reported using anabolic steroids, 72.6% were sports participants. Steroid users, whether they participated in sports or not, were more likely to use alcohol, tobacco, and other drugs than were nonusers of steroids. Among sports participants and nonparticipants, anabolic steroid users were more likely than nonusers to report acting violently. Nebraska students (grades 7 through 12) who participated in school-sponsored sports were more likely than non-participants to use anabolic steroids. Steroid-using athletes were more likely to use alcohol, tobacco, and other drugs than athletes who did not use steroids.

Intrapleural administration of vitreous high duty ceramic fibres and heated devitrified ceramic fibres does not give rise to pleural mesothelioma in rats.

In order to determine whether they are potentially carcinogenic to the pleural mesothelium, three samples of ceramic fibre have been administered to rats by the intrapleural route. These samples were a high-duty grade refractory ceramic fibre (manufactured by Thermal Ceramics Ltd) in the as-manufactured vitreous state and two devitrified samples produced by heating the same fibre for 2 weeks at 1200 degrees C and for two weeks at 1400 degrees C. The mean lifespans of the groups of rats treated with vitrified and devitrified ceramic fibres were not significantly different from that of the control rats. In these studies none of the treated or control rats developed pleural mesothelioma, making it unlikely that ceramic fibres of this type, whether vitreous or devitrified, are potentially carcinogenic to the pleural mesothelium.

Representing clinical narratives using conceptual graphs.

The analysis of medical narratives and the generation of natural language expressions are strongly dependent on the existence of an adequate representation language. Such a language has to be expressive enough in order to handle the complexity of human reasoning in the domain. Sowa's Conceptual Graphs (CG) are an answer, and this paper presents a multilingual implementation, using French, English and German. Current developments demonstrate the feasibility of an approach to natural Language Understanding where semantic aspects are dominant, in contrast to syntax driven methods. The basic idea is to aggregate blocks of words according to semantic compatibility rules, following a method called Proximity Processing. The CG representation is gradually built, starting from single words in a semantic lexicon, to finally give a complete representation of the sentence under the form of a single CG. The process is dependent on specific rules of the medical domain, and for this reason is largely controlled by the declarative knowledge of the medical Linguistic Knowledge Base.

Multilingual natural language generation as part of a medical terminology server.

Re-usable and sharable, and therefore language-independent concept models are of increasing importance in the medical domain. The GALEN project (Generalized Architecture for Languages Encyclopedias and Nomenclatures in Medicine) aims at developing language-independent concept representation systems as the foundations for the next generation of multilingual coding systems. For use within clinical applications, the content of the model has to be mapped to natural language. A so-called Multilingual Information Module (MM) establishes the link between the language-independent concept model and different natural languages. This text generation software must be versatile enough to cope at the same time with different languages and with different parts of a compositional model. It has to meet, on the one hand, the properties of the language as used in the medical domain and, on the other hand, the specific characteristics of the underlying model and its representation formalism. We propose a semantic-oriented approach to natural language generation that is based on linguistic annotations to a concept model. This approach is realized as an integral part of a Terminology Server, built around the concept model and offering different terminological services for clinical applications.

Analysis of medical texts based on a sound medical model.

Automatic understanding of natural language is a complex task due to the presence of ambiguities. In particular, semantic ambiguities which are often immediately and unconsciously solved by human beings, are raised when analyzing natural language sentences by computer. The latter has to know the implicit and contextual information in order to resolve these difficulties. Nowadays in medicine, a considerable effort is deployed to model semantic contents of the medical domain. Such a task is usually performed separately from linguistic considerations. The goal of this paper is to highlight the key issues of basing a medical language processing system on a sound semantic model. To illustrate the requirements and advantages of such a conceptual approach to the analysis process, the experiment conducted to adjust the RECIT analyzer to the GALEN model is shown.

Fiber levels and disease in workers from a factory predominantly using amosite.

The Cape Boards Plant at Uxbridge produced insulation board containing amosite asbestos between 1947 and 1973 with only small amounts of chrysotile. After 1973 only amosite was used. In this study we examined lung samples from 48 workers who had been employed at the plant and who had come to autopsy. The study investigated the fiber levels against the lung pathology including amount of interstitial fibrosis and numbers of ferruginous bodies. The degree of interstitial fibrosis and number of asbestos bodies were graded and the tissues were analyzed by transmission electron microscopy and energy dispersive X-ray analysis and the fibers counted and typed. The 48 cases included 5 mesotheliomas and 14 lung cancers. The mineral analysis results were dominated by the amosite fiber levels. The amounts of chrysotile were relatively small. There were higher levels in lung cancer cases than mesotheliomas and higher levels in mesothelioma cases than those who had died from nonasbestos related diseases. Analysis of the lung tissues showed a consistent pattern of high amosite levels, which confirms the impression that amosite was the predominant form of asbestos used and also indicates that the factory had been a very dusty one.

A study of Spanish sepiolite workers.

BACKGROUND: Sepiolite is an absorbent clay that is used as pet litter. It forms thin crystals, which are a transition between chain and layered silicates. Inhalation studies in animals have shown no evidence of pulmonary damage. This paper reports a cross sectional study of the total work force of the largest sepiolite production plant in the world. METHODS: Two hundred and eighteen workers (210 men and eight women) were studied. Height, age, and smoking history were recorded. Chest radiographs were read according to the International Labour Office (ILO) classification by two readers. Readings were used to construct a numerical score, which was then used in statistical analyses. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were divided by the square of the height. Casella size selective personal samplers were used in randomly selected operatives to collect dust eight years before the rest of the study was carried out. These samples were evaluated gravimetrically. Total dust samples were examined by optical and electron microscopes. Results were analysed by bivariate linear regression, chi 2 tests, and analysis of variance. RESULTS: When allowance was made for smoking habit workers exposed to dry dust showed a significantly greater decline in FEV1 with age than workers with little exposure to dry dust. A similar pattern applied to FVC. Radiographic score showed deterioration with age but no clear differences from other variables. High concentrations of dust were found in the bagging department and also in the classifier shed. CONCLUSIONS: The major finding was that lung function deteriorated more rapidly in those who had had more exposure to dust, but there was no evidence of any accompanying radiographic change.

[Double trans-suture technique in colorectal surgical anastomosis. Apropos of 45 cases]. / Anastomose double trans-suturaire dans la chirurgie colo-rectale. A propos de 45 observations.

The double trans-suture technique in colorectal anastomoses is an entirely mechanical one which consist of the transformation of two linear sutures in a circular one. During, 2 years, between March 1990 and March 1992, this technique was performed on 45 patients, of whom about two-third had a carcinoma of rectosigmoid. No postoperative mortality occurred. One patient developed an anastomatic stenosis, and another one a clinical leakage. The double trans-suture technique has not only the advantages of the double stapling technique but also avoids the incidents of performing a proximal purse.

Purification and characterization of proteinase yscJ, a new yeast peptidase.

A newly recognized peptidase, designated proteinase yscJ, was purified from the yeast Saccharomyces cerevisiae. The enzyme is of non-vacuolar origin and cleaves the Tyr-Lys bond of the synthetic peptide substrate Cbz-Tyr-Lys-Arg-NH-Ph (Cbz, benzyloxycarbonyl; NH-Ph, 4-nitroanilide) and the Glu-Lys bond of the substrate Boc-Glu-Lys-Lys-NH-Mec (Boc, butoxycarbonyl; Mec, 4-methylcoumarinyl) with high efficiency. Optimum pH for cleavage of Cbz-Tyr-Lys-Arg-NH-Ph is in the range 7.0-7.5. The purified enzyme has a molecular mass of approximately 58 kDa, as judged by gel filtration on a Superose 12 FPLC column. Mercury compounds and EDTA were found to be potent inhibitors of proteinase yscJ activity.