Markers for Major Complications at Day-One Postoperative in Fast-Track Metabolic Surgery: Updated Metabolic Checklist.

INTRODUCTION: In fast-track metabolic surgery, the window to identify complications is narrow. Postoperative checklists can be useful tools in the decision-making of safe early discharge. The aim of this study was to evaluate the predictive value of a checklist used in metabolic surgery. METHODS: Retrospective data from June 2018 to January 2021 was collected on all patients that underwent metabolic surgery in a high-volume bariatric hospital in the Netherlands. Patients without an available checklist were excluded. The primary outcome was major complications and the secondary outcomes were minor complications, readmission, and unplanned hospital visits within 30 days postoperatively. RESULTS: Major complications within 30 days postoperatively occurred in 62/1589 (3.9%) of the total included patients. An advise against early discharge was significantly more seen in patients with major complications compared to those without major complications (90.3% versus 48.1%, P < 0.001, respectively), and a negative checklist (advice for discharge) had a negative predictive value of 99.2%. The area under the curve for the total checklist was 0.80 (P < 0.001). Using a cut-off value of ≥3 positive points, the sensitivity and specificity were 65% and 82%, respectively. Individual parameters from the checklist: oral intake, mobilization, calf pain, willingness for discharge, heart rate, drain (>30 ml/24 h), hemoglobin, and leukocytes count were also significantly different between groups. CONCLUSION: This checklist is a valuable tool to decide whether patients can be safely discharged early. Heart rate appeared to be the most predictive parameter for the development of major complications. Future studies should conduct prediction models to identify patients at risk for major complications.

Peroperative administration of tranexamic acid in sleeve gastrectomy to reduce hemorrhage: a double-blind randomized controlled trial.

INTRODUCTION: In metabolic surgery, hemorrhage is the most common major complication. This study investigated whether peroperative administration of tranexamic acid (TXA) reduced the risk of hemorrhage in patients undergoing laparoscopic sleeve gastrectomy (SG). METHODS: In this double-blind randomized controlled trial, patients undergoing primary SG in a high-volume bariatric hospital were randomized (1:1) to receive 1500-mg TXA or placebo peroperatively. Primary outcome measure was peroperative staple line reinforcement using hemostatic clips. Secondary outcome measures were peroperative fibrin sealant use and blood loss, postoperative hemoglobin, heart rate, pain, major and minor complications, length of hospital stay (LOS), side effects of TXA (i.e., venous thrombotic event (VTE)) and mortality. RESULTS: In total, 101 patients were analyzed and received TXA (n = 49) or placebo (n = 52). There was no statistically significant difference in hemostatic clip devices used in both groups (69% versus 83%, p = 0.161). TXA administration showed significant positive changes in hemoglobin levels (millimoles per Liter; 0.55 versus 0.80, p = 0.013), in heart rate (beats per minute; -4.6 versus 2.5; p = 0.013), in minor complications (Clavien-Dindo ≤ 2, 2.0% versus 17.3%, p = 0.016), and in mean LOS (hours; 30.8 versus 36.7, p = 0.013). One patient in the placebo-group underwent radiological intervention for postoperative hemorrhage. No VTE or mortality was reported. CONCLUSION: This study did not demonstrate a statistically significant difference in use of hemostatic clip devices and major complications after peroperative administration of TXA. However, TXA seems to have positive effects on clinical parameters, minor complications, and LOS in patients undergoing SG, without increasing the risk of VTE. Larger studies are needed to investigate the effect of TXA on postoperative major complications.

Microrheology and Spatial Heterogeneity of Staphylococcus aureus Biofilms Modulated by Hydrodynamic Shear and Biofilm-Degrading Enzymes.

Particle tracking microrheology was used to investigate the viscoelasticity of Staphylococcus aureus biofilms grown in microfluidic cells at various flow rates and when subjected to biofilm-degrading enzymes. Biofilm viscoelasticity was found to harden as a function of shear rate but soften with increasing height away from the attachment surface in good agreement with previous bulk results. Ripley's K-function was used to quantify the spatial distribution of the bacteria within the biofilm. For all conditions, biofilms would cluster as a function of height during growth. The effects of proteinase K and DNase-1 on the viscoelasticity of biofilms were also investigated. Proteinase K caused an order of magnitude change in the compliances, softening the biofilms. However, DNase-1 was found to have no significant effects over the first 6 h of development, indicating that DNA is less important in biofilm maintenance during the initial stages of growth. Our results demonstrate that during the preliminary stages of Staphylococcus aureus biofilm development, column-like structures with a vertical gradient of viscoelasticity are established and modulated by the hydrodynamic shear caused by fluid flow in the surrounding environment. An understanding of these mechanical properties will provide more accurate insights for removal strategies of early-stage biofilms.

Measured versus predicted energy expenditure in children with inactive Crohn's disease.

INTRODUCTION: The aim of the study was to assess if the estimated average requirements for energy for normal children (EAR) and the Schofield equation could reliably predict energy requirements in children with inactive Crohn's disease (CD). METHODS: Twenty-three children with inactive CD were studied, median age 14.3 years (range 7.8-16.9). Resting energy expenditure (REE) was measured by indirect calorimetry and compared with that predicted using the Schofield equation (BMR). Total energy expenditure (TEE) was measured using REE and a 3-day activity diary and compared with EAR. RESULTS: REE ranged from 79% to 136% of BMR. Mean REE was not significantly greater than mean BMR (P=0.25 2-tailed t-test). TEE ranged from 72% to 163% of estimated average requirements for energy for children of that weight (EARw). EARw tended to underestimate TEE in large children and overestimate TEE in small children (Bland-Altman plot R=0.5, P=0.002). EARw was a poor predictor of TEE (R=0.35, P=0.1). EAR underestimated energy requirements by >500 kcal/day in 40% of the children. CONCLUSIONS: The Schofield equation and EAR are unreliable methods of predicting total energy requirements in children with inactive CD with a significant potential to underestimate energy needs. When energy requirements were greater than EAR it was due to physical activity and body habitus rather than raised REE.

Integrated risk assessment or integrated risk management?

Problems of hazard assessment and risk assessment are at the present time the subjects of considerable discussion in the context of the Organisation for Economic Cooperation and Development (OECD) chemical management programs, within the European Community (EEC) and at national levels. A previous article (J. W. Hart and N. J. Jensen, 1990, Regul. Toxicol. Pharmacol. 11, 123-131) discussed the inherent limitations of the hazard assessment of chemicals. The elements of hazard and risk assessment have been described by Bro-Rasmussen (In Risk Assessment of Chemicals in the Environment, M. L. Richardson, Ed., Chap. 24, pp. 437-450, Royal Society of Chemistry, London, 1988). This article is an attempt to illustrate the different elements in hazard and risk assessments in specific risk management areas and to indicate the limitations in these processes. This analysis indicates that there are different requirements for a risk assessment, which depend on its specific purpose. In particular, problems related to the integration of different approaches--and the stage at which integration is possible--are discussed. While the principle subject of the discussion is risk assessment, many of the elements concerned are also a part of priority setting, and this subject is also discussed briefly.

The myth of the final hazard assessment.

Hazard assessment is a basic tool used in the evaluation and regulation of chemicals, but in spite of this there are many different interpretations of the scope and function of a hazard assessment. Starting from a discussion of the essential elements and conceptual frames involved, an attempt is made to identify the sources of uncertainty that are inherent in a hazard assessment. Problems identified include unambiguous identification of the chemical source, the routes of exposure, and the possible targets to be considered. Inadequacies in effects data are frequent, but unlike many of the other sources of uncertainty, these are often compensated for by the use of safety factors when setting quantitative limits for human or environmental exposure. The inherent uncertainties in the process make periodic revisions of any hazard assessment process inevitable, as new knowledge on routes of exposure and targets becomes available.

New light on the cholodny-went theory.

The existence of different auxin sensitivities in epidermal and subepidermal tissues (KV Thimann, CL Schneider 1938 Plant Physiol 25: 627-641) suggests a refinement to the Cholodny-Went theory which overcomes some of the difficulties associated with it. A model is presented to account for the inverse tropic responses of shoots and roots through differences in the respective locations of the auxin-sensitive tissues.

Apical involvement in geogrowth responses of the horizontal hypocotyl.

Hypocotyls of horizontal sunflower (Helianthus annuus L.) seedlings grow more than those of vertical seedlings during the 24 h period following geostimulus. The major contribution to this increased growth arises from extension in the basal half of the geostimulated hypocotyls. H seedling hypocotyls are flexed to a right angle so that the apical half is vertical and the basal half is horizontal, the growth rate of the basal half is similar to that of a vertical hypocotyl rather than a horizontal hypocotyl. These results are taken as indicating that the georesponse of the basal half is not independent of the apical half. It is concluded that the apical region exercises a co-ordinating role in the overall response of the hypocotyl to geostimulation.

The role of the apex in normal and tropic growth of sunflower hypocotyls.

Regional growth in vertical and horizontal etiolated sunflower hypocotyls from which the apical hook tissue had been either partly or wholly excised, was measured 24 h later, the regions having been demarcated with resin beads. Removal of the cotyledons (an excision which included the distal end of the shoot apex) had little effect on growth during this period but excision of the apical hook significantly reduced growth. In vertically orientated seedlings, removal of half of the hook severely reduced growth in all other growing regions and removal of the entire hook totally inhibited growth. This inhibition of growth was not a consequence of the removal of the region of growth but a consequence of the removal of a region on which growth was dependent. In horizontal seedlings, the situation was more complex inasmuch as a horizontal orientation itself induced growth in previously non-growing regions. This new growth was localised in its extent and was not as severely affected by progressive excision of the hook as was growth in vertical seedlings. The results are discussed in terms of overall growth co-ordination in the hypocotyl.

Image Analysis of Geo-Induced Inhibition, Compression, and Promotion of Growth in an Inverted Helianthus annuus L. Seedling.

The growth responses of a sunflower seedling (Helianthus annuus L.), subjected to repeated inversion, were characterized by time-lapse recording in conjunction with video image analysis. The investigation revealed a characteristic response pattern and established that the directional movement of the seedling is achieved by both inhibition and stimulation of growth in the normal growing regions. The complex growth changes in contiguous regions of the hypocotyl are such as seem to be inexplicable in terms of an environmentally imposed gradient of a single growth substance.

Is there a role for the apex in shoot geotropism?

Experiments with horizontal etiolated sunflower (Helianthus annuus L.) seedlings supported centrally such that both apical and basal ends are free to react to geostimulus, revealed that the apical end commences curvature 1 to 2 hours earlier than the basal end. The later curvature in the basal region is a consequence of the absence of growth in the initial period rather than merely slower growth. A comparison of zonal growth rates in a vertical and a horizontal seedling confirmed that geostimulus induces a renewal of growth in a region where growth had ceased. Removing the apical half of the hypocotyl showed that the curvature resulting from this growth initiation in the basal region is dependent on attachment to the apical region. Evidence that this dependence is unlikely to be due to energy deficiency is adduced. The prior response of the apical end to geostimulus and the apically dependent later initiation of new growth in the basal region are compatible with the delay inherent in message transport from apex to base and are considered as evidence for apical involvement in the totality of the seedling's georesponse.

The influence of adjacent tissue on hypocotyl hook opening.

The influence of the cotyledons and the tissue forming the proximal end of the hook in Helianthus annuus L. and Phaseolus mungo L. seedlings growing in the dark has been examined by comparing the growth of whole and decapitated seedlings in which the hook region was demarcated by the use of resin beads as surface markers. It is shown that although decapitated seedlings straighten and whole seedlings maintain a hooked configuration, the curved region in the control seedlings corresponding to that remaining in the decapitated plants also undergoes straightening in the course of the experiment. Maintenance of the hook in controls is thus a consequence of the continuous shifting of the differential growth to a more apical region which decapitation removes. The significance of this finding in relation to the suggestion that cotyledons export an endogenous hook-shutting factor is indicated.

Statistics of the mouse bone-marrow micronucleus test: counting, distribution and evaluation of results.

The distribution of historical control results from male mice tested in the bone-marrow micronucleus test was used to optimize counting procedures and to develop decision rules for evaluating test results. The ratio of normochromatic to polychromatic erythrocytes followed a normal distribution, while the incidence of micronucleated polychromatic and normochromatic erythrocytes followed a binomial distribution. Recommendations for the number of cells to be scored per animal and for the evaluation of results are based on these distributions and the two-hypothesis multiple-decision approach of Selby and Olsen (1981).

Induction of micronuclei in the mouse. Revised timing of the final stage of erythropoiesis.

The early effects of X-rays, vincristine, cyclophosphamide, quinacrine dihydrochloride, cycloheximide, actinomycin D and hydroxyurea on the induction of micronuclei in mouse bone-marrow erythrocytes were studied. A significant increase in the incidence of micronuclei in polychromatic erythrocytes was seen as early as 5 h after a single treatment with vincristine, 6 h after treatment with X-rays and 10 h after treatment with cyclophosphamide. The cell kinetics of the mouse erythropoietic system described by Cole et al. (1981) can be modified to fit these results. According to this revised model, the final mitosis takes place only 5 h before the expulsion of the nucleus.

The positive hook: the role of gravity in the formation and opening of the apical hook.

Photographic observations on germinating seedlings of Lepidium sativum L., Cucumis sativus L., and Helianthus annuus L. showed that the hypocotyl hook is not present in the seed but forms during the early stages of growth. Evidence that gravity plays a major role in inducing curvature of the hypocotyl, and in maintaining the hook once it has been formed, was obtained from clinostat experiments, from the use of morphactin to remove geotropic sensitivity and from inversion of seedlings to change the direction of the geostimulus. In L. sativum and H. annuus gravity perception seemed to be the only mechanism responsible for hook formation. In C. sativus hook formation was additionally aided by the mode of emergence of the cotyledons from the seed coat but gravity played an indirect role in regulating such emergence. Further evidence that hook formation is linked to a georesponse was derived from a comparison of hypocotyl development in wild-type Arabidopsis thaliana seedlings with that of an ageotropic mutant, hook formation being found to occur only in the wild type. Hook formation and maintenance is discussed in terms of contrasting geosensitivity between the apical and basal ends of the hypocotyl and it is suggested that light-induced hook opening is a reversal to a condition of uniformly negative georesponse throughout the hypocotyl.

Pharmacokinetics and distribution of the new antihypertensive agent pinacidil in rat, dog and man.

1. The antihypertensive agent pinacidil was rapidly, and almost completely, absorbed following oral administration of 0.5 mg/kg of the [14C]pinacidil monohydrate to rats and dogs. The half-life was about 1 and 2 h in the two species, respectively. A bioavailability of 80% of unchanged pinacidil in the rat suggests a first-pass effect in this species. 2. After oral and intravenous administration of [14C]pinacidil about 85% of the radioactivity was recovered in the urine and 15% in the faeces in rats and dogs; 80-90% was excreted during the first 24 h. Autoradiographic studies in the rat showed similar distributions after oral and intravenous administration. 3. An oral dose of 5 or 10 mg pinacidil monohydrate was rapidly absorbed in healthy volunteers and had a pharmacokinetic profile very similar to that found in rats and dogs. Concomitant food ingestion did not change the bioavailability of the drug.

Calcium-binding protein in sieve tube exudate.

A calcium-binding macromolecule, with an estimated molecular weight greater than 100,000, was detected in phloem exudate from Cucurbita maxima and related species. The macromolecule was a component of sieve tube sap, rather than a contaminant leached from cell walls or cut parenchyma cells during exudate collection. The protein nature of this macromolecule was deduced from its size, lability, susceptibility to proteolytic digestion, and by the dependence of calcium-binding activity on thiol-protecting agents. This protein is distinct from the major proteins of exudate and does not appear to be related to calmodulin.

Heterogeneity in phloem protein complements from different species : Consequences of hypotheses concerned with P-protein function.

Protein subunits present in phloem exudate from 17 cultivars, 5 species and 3 genera of the Cucurbitaceae have been fractionated by SDS-gel electrophoresis. The degree of difference in the phloem protein patterns appears to reflect the taxonomic relationships of the plants: there were major differences among genera, significant differences and similarities among species, and relatively few differences among cultivars of a single species. A representative of another family (Acer pseudoplatanus; Aceraceae) provided a completely different electrophoretic pattern. Each plant displayed a consistent protein pattern, irrespective of the organ from which exudate was obtained or the age and physiological status of the plant. Neither complete etiolation nor transition to the flowering phase effected any change in phloem proteins. The differences in phloem proteins between plants and the unusual properties of major subunits from different protein complements, render improbable many of the present ideas concerning the origin and function of P-protein.

A study of three preventive approaches to low back injury.

The prevention of low back injuries in industry has traditionally been attempted by (1) careful selection of workers, (2) good training in safe lifting, and (3) designing the job to fit the worker (ergonomics). One hundred ninety-one low back injuries were analyzed to determine the effectiveness of each preventive approach. The results indicate that the common selection techniques, as they are being used today, are not an effective control for low back injuries. Similarly, training on safe lifting procedures, as it is being administered today, is not an effective control for low back injuries. It was determined that a worker is three times more susceptible to low back injury if exposed to excessive manual handling tasks. The ergonomic redesign of these tasks to reduce the manual handling exposure represents a partial control for low back injuries.