Retrospective Analysis of Risk Factors in Geriatric Hip Fracture Patients Predictive of Surgical Intensive Care Unit Admission.

INTRODUCTION: Although numerous risk factors and prediction models affecting morbidity and mortality in geriatric hip fracture patients have been previously identified, there are scant published data on predictors for perioperative Surgical Intensive Care Unit (SICU) admission in this patient population. Determining if a patient will need an SICU admission would not only allow for the appropriate allocation of resources and personnel but also permit targeted clinical management of these patients with the goal of improving morbidity and mortality outcomes. The purpose of this study was to identify specific risk factors predictive of SICU admission in a population of geriatric hip fracture patients. Unlike previous studies which have investigated predominantly demographic, comorbidity, and laboratory data, the present study also considered a frailty index and length of time from injury to presentation in the Emergency Department (ED). METHODS: A total of 501 geriatric hip fracture patients admitted to a Level 1 trauma center were included in this retrospective, single-center, quantitative study from January 1, 2019, to December 31, 2022. Using a logistical regression analysis, more than 25 different variables were included in the regression model to identify values predictive of SICU admission. Predictive models of planned versus unplanned SICU admissions were also estimated. The discriminative ability of variables in the final models to predict SICU admission was assessed with receiver operating characteristic curves' area under the curve estimates. RESULTS:  Frailty, serum lactate > 2, and presentation to the ED > 12 hours after injury were significant predictors of SICU admission overall (P = 0.03, 0.038, and 0.05 respectively). Additionally, the predictive model for planned SICU admission had no common significant predictors with unplanned SICU admission. Planned SICU admission significant predictors included an Injury Severity Score (ISS) of 15 and greater, a higher total serum protein, serum sodium <135, systolic blood pressure (BP) under 100, increased heart rate on admission to ED, thrombocytopenia (<120), and higher Anesthesia Society Association physical status classification (ASA) score (P = 0.007, 0.04, 0.05, 0.002, 0.041, 0.05, and 0.005 respectively). Each SICU prediction model (overall, planned, and unplanned) demonstrated sufficient discriminative ability with the area under the curve (AUC) values of 0.869, 0.601, and 0.866 respectively. Finally, mean hospital Length of Stay (LOS) and mortality were increased in SICU admissions when compared to non-SICU admissions. CONCLUSION: Of the three risk factors predictive of SICU admission identified in this study, two have not been extensively studied previously in this patient population. Frailty has been associated with increased mortality and postoperative complications in hip fracture patients, but this is the first study to date to use a novel frailty index specifically designed and validated for use in hip fracture patients. The other risk factor, time from injury to presentation to the ED serves as an indicator for time a hip fracture patient spent without receiving medical attention. This risk factor has not been investigated heavily in the past as a predictor of SICU admissions in this patient population.

New alternative ingredients and genetic selection are the next game changers in rainbow trout nutrition: a metabolomics appraisal.

The formulation of sustainable fish feeds based on plant ingredients supplemented by alternative ingredients to plant (insect, micro-algae, yeast) and genetic selection of fish for plant-based diets were tested on rainbow trout in two separate experiments. Plant-based diets and corresponding diets supplemented with an ingredient mix: insect, micro-algae and yeast in Experiment A, and insect and yeast in Experiment B were compared to commercial-like diets. In experiment A, the mix-supplemented diet was successful in compensating the altered growth performance of fish fed their respective plant-based diet compared to those fed the commercial diet, by restoring feed conversion. In experiment B, the selected line demonstrated improved growth performances of fish fed mix-supplemented and plant-based diets compared to the non-selected line. Metabolomics demonstrated a plasma compositional stability in fish fed mix-supplemented and basal plant-based diets comprising an amino acid accumulation and a glucose depletion, compared to those fed commercial diets. The selected line fed mix-supplemented and commercial diets showed changes in inositol, ethanol and methanol compared to the non-selected line, suggesting an involvement of microbiota. Changes in plasma glycine-betaine content in fish fed the mix-supplemented diet suggest the ability of the selected line to adapt to alternative ingredients.

Gene expression profiling of trout muscle during flesh quality recovery following spawning.

BACKGROUND: Sexual maturation causes loss of fish muscle mass and deterioration of fillet quality attributes that prevent market success. We recently showed that fillet yield and flesh quality recover in female trout after spawning. To gain insight into the molecular mechanisms regulating flesh quality recovery, we used an Agilent-based microarray platform to conduct a large-scale time course analysis of gene expression in female trout white muscle from spawning to 33 weeks post-spawning. RESULTS: In sharp contrast to the situation at spawning, muscle transcriptome of female trout at 33 weeks after spawning was highly similar to that of female trout of the same cohort that did not spawn, which is consistent with the post-spawning flesh quality recovery. Large-scale time course analysis of gene expression in trout muscle during flesh quality recovery following spawning led to the identification of approximately 3340 unique differentially expressed genes that segregated into four major clusters with distinct temporal expression profiles and functional categories. The first cluster contained approximately 1350 genes with high expression at spawning and downregulation after spawning and was enriched with genes linked to mitochondrial ATP synthesis, fatty acid catabolism and proteolysis. A second cluster of approximately 540 genes with transient upregulation 2 to 8 weeks after spawning was enriched with genes involved in transcription, RNA processing, translation, ribosome biogenesis and protein folding. A third cluster containing approximately 300 genes upregulated 4 to 13 weeks after spawning was enriched with genes encoding ribosomal subunits or regulating protein folding. Finally, a fourth cluster that contained approximately 940 genes with upregulation 8 to 24 weeks after spawning, was dominated by genes encoding myofibrillar proteins and extracellular matrix components and genes involved in glycolysis. CONCLUSION: Overall, our study indicates that white muscle tissue restoration and flesh quality recovery after spawning are associated with transcriptional changes promoting anaerobic ATP production, muscle fibre hypertrophic growth and extracellular matrix remodelling. The generation of the first database of genes associated with post-spawning muscle recovery may provide insights into the molecular and cellular mechanisms controlling muscle yield and fillet quality in fish and provide a useful list of potential genetic markers for these traits.

Understanding the Determination of Meat Quality Using Biochemical Characteristics of the Muscle: Stress at Slaughter and Other Missing Keys.

Despite increasingly detailed knowledge of the biochemical processes involved in the determination of meat quality traits, robust models, using biochemical characteristics of the muscle to predict future meat quality, lack. The neglecting of various aspects of the model paradigm may explain this. First, preslaughter stress has a major impact on meat quality and varies according to slaughter context and individuals. Yet, it is rarely taken into account in meat quality models. Second, phenotypic similarity does not imply similarity in the underlying biological causes, and several models may be needed to explain a given phenotype. Finally, the implications of the complexity of biological systems are discussed: a homeostatic equilibrium can be reached in countless ways, involving thousands of interacting processes and molecules at different levels of the organism, changing over time and differing between animals. Consequently, even a robust model may explain a significant part, but not all of the variability between individuals.

Predicting the Quality of Meat: Myth or Reality?

This review is aimed at providing an overview of recent advances made in the field of meat quality prediction, particularly in Europe. The different methods used in research labs or by the production sectors for the development of equations and tools based on different types of biological (genomic or phenotypic) or physical (spectroscopy) markers are discussed. Through the various examples, it appears that although biological markers have been identified, quality parameters go through a complex determinism process. This makes the development of generic molecular tests even more difficult. However, in recent years, progress in the development of predictive tools has benefited from technological breakthroughs in genomics, proteomics, and metabolomics. Concerning spectroscopy, the most significant progress was achieved using near-infrared spectroscopy (NIRS) to predict the composition and nutritional value of meats. However, predicting the functional properties of meats using this method-mainly, the sensorial quality-is more difficult. Finally, the example of the MSA (Meat Standards Australia) phenotypic model, which predicts the eating quality of beef based on a combination of upstream and downstream data, is described. Its benefit for the beef industry has been extensively demonstrated in Australia, and its generic performance has already been proven in several countries.

Early fish myoseptal cells: insights from the trout and relationships with amniote axial tenocytes.

The trunk muscle in fish is organized as longitudinal series of myomeres which are separated by sheets of connective tissue called myoseptum to which myofibers attach. In this study we show in the trout that the myoseptum separating two somites is initially acellular and composed of matricial components such as fibronectin, laminin and collagen I. However, myoseptal cells forming a continuum with skeletogenic cells surrounding axial structures are observed between adjacent myotomes after the completion of somitogenesis. The myoseptal cells do not express myogenic markers such as Pax3, Pax7 and myogenin but express several tendon-associated collagens including col1a1, col5a2 and col12a1 and angiopoietin-like 7, which is a secreted molecule involved in matrix remodelling. Using col1a1 as a marker gene, we observed in developing trout embryo an initial labelling in disseminating cells ventral to the myotome. Later, labelled cells were found more dorsally encircling the notochord or invading the intermyotomal space. This opens the possibility that the sclerotome gives rise not only to skeletogenic mesenchymal cells, as previously reported, but also to myoseptal cells. We furthermore show that myoseptal cells differ from skeletogenic cells found around the notochord by the specific expression of Scleraxis, a distinctive marker of tendon cells in amniotes. In conclusion, the location, the molecular signature and the possible sclerotomal origin of the myoseptal cells suggest that the fish myoseptal cells are homologous to the axial tenocytes in amniotes.

Changes in white muscle transcriptome induced by dietary energy levels in two lines of rainbow trout (Oncorhynchus mykiss) selected for muscle fat content.

Energy intake and genetic background are major determinants of muscle fat content in most animals, including man. We combined genetic selection and dietary energy supply to study the metabolic pathways involved in genetic and nutritional control of fat deposition in the muscle of rainbow trout (Oncorhynchus mykiss). Two experimental lines of rainbow trout, selected for lean (L) or fat (F) muscle, were fed with diets containing either 10 or 23 % lipids from the first feeding, up to 6 months. At the end of the trial, trout exhibited very different values of muscle fat content (from 4.2 to 10.1 % wet weight). Using microarrays made from a rainbow trout multi-tissue cDNA library, we analysed the molecular changes occurring in the muscle of the two lines when fed the low-energy or high-energy diet. The results from microarray analysis revealed that eleven metabolism-related genes were differentially expressed according to the diet while selection resulted in expression change for twenty-six genes. The most striking observation was the increased level of transcripts encoding the VLDL receptor and fatty acid translocase/CD36 following both the high-fat diet and upward selection for muscle fat content, suggesting that these two genes are relevant molecular markers of fat deposition in the white muscle of rainbow trout.

Differentially expressed proteins in rainbow trout adipocytes isolated from visceral and subcutaneous tissues.

In rainbow trout, subcutaneous (in dorsal and ventral positions) and visceral fat deposits are known to influence the yield of edible flesh, whilst their respective roles in metabolism, storage and release of fatty acids have not, so far, been directly studied. The present work aimed to identify, by using 2D electrophoresis, proteins differentially expressed in isolated mature adipocytes originating from these various localizations in prepubescent females. A total of nine proteins were estimated to be differentially expressed according to the localisation of the adipocytes. Seven protein spots were considered to be present in the three fat deposits at differing abundances, and among them only six were estimated as being specific to fat tissues. Among these, five were more abundant in subcutaneous adipocytes of both sites compared to perivisceral adipocytes. Four were identified: three as H-FABP, ATP synthase, serum deprivation-response protein, indicating higher metabolic activity in subcutaneous adipocytes, while the latter, annexin, indicative of a higher proportion of less mature adipocytes, as also suggested by their smaller mean diameter. The more abundant protein in visceral isolated adipocytes is actin, known to be involved in cytoskeleton structure and to increase during adipogenesis. This allows us to suggest their more mature stage of development, in relation with their higher mean diameter.

Changes induced by dietary energy intake and divergent selection for muscle fat content in rainbow trout (Oncorhynchus mykiss), assessed by transcriptome and proteome analysis of the liver.

BACKGROUND: Growing interest is turned to fat storage levels and allocation within body compartments, due to their impact on human health and quality properties of farm animals. Energy intake and genetic background are major determinants of fattening in most animals, including humans. Previous studies have evidenced that fat deposition depends upon balance between various metabolic pathways. Using divergent selection, we obtained rainbow trout with differences in fat allocation between visceral adipose tissue and muscle, and no change in overall body fat content. Transcriptome and proteome analysis were applied to characterize the molecular changes occurring between these two lines when fed a low or a high energy diet. We focused on the liver, center of intermediary metabolism and the main site for lipogenesis in fish, as in humans and most avian species. RESULTS: The proteome and transcriptome analyses provided concordant results. The main changes induced by the dietary treatment were observed in lipid metabolism. The level of transcripts and proteins involved in intracellular lipid transport, fatty acid biosynthesis and anti-oxidant metabolism were lower with the lipid rich diet. In addition, genes and proteins involved in amino-acid catabolism and proteolysis were also under expressed with this diet. The major changes related to the selection effect were observed in levels of transcripts and proteins involved in amino-acid catabolism and proteolysis that were higher in the fat muscle line than in the lean muscle line. CONCLUSION: The present study led to the identification of novel genes and proteins that responded to long term feeding with a high energy/high fat diet. Although muscle was the direct target, the selection procedure applied significantly affected hepatic metabolism, particularly protein and amino acid derivative metabolism. Interestingly, the selection procedure and the dietary treatment used to increase muscle fat content exerted opposite effects on the expression of the liver genes and proteins, with little interaction between the two factors. Some of the molecules we identified could be used as markers to prevent excess muscle fat accumulation.

Thermal denaturation and aggregation properties of Atlantic salmon myofibrils and myosin from white and red muscles.

Thermal denaturation and aggregation abilities of salmon myofibrils and myosin were studied measuring turbidity, intrinsic fluorescence, 8-anilino-1-naphthalene sulfonic acid binding, and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide cross-linking. The thermal behaviors of protein preparation from white and red muscles were compared, and the relationship with thermal gelation properties is discussed. The low gelation ability of salmon muscle proteins was related to a limited extent of protein denaturation and aggregation upon heating. These properties seemed to be carried by myosin molecules as a similar behavior was observed for both myofibrils and myosin preparations. The higher thermal stability observed for red muscle proteins with higher transition temperatures in rheological profiles was related to a shift to higher temperature in denaturation and aggregation processes. The extent of denaturation and aggregation was very similar for both muscle types as was the final rigidity of the gels formed.

Modifications of trout (Oncorhynchus mykiss) muscle proteins by preslaughter activity.

The effect of two different preslaughter procedures (limited or 15-min intense muscular activity) on muscle trout proteins was investigated. Muscle was sampled 45 min and 24 h post-mortem, proteins were separated using two-dimensional electrophoresis, and spots of interest were tentatively identified by MALDI-TOF spectrometry. Twenty-nine and 4 spots were differentially represented between the two groups of fish at 45 min and 24 h post-mortem, respectively. Spots that could be identified corresponded mainly to proteins involved in energy-producing pathways (triosephosphate isomerase, enolase, pyruvate dehydrogenase) or to structural proteins (desmin, cap-Z, myosin heavy chain fragment). Persistent under-representation of desmin, a key cytoskeletal protein, in fish submitted to intense muscular activity suggests that such a preslaughter treatment can have an effect on post-mortem muscle integrity.