203 research outputs found
Circular frame fixation for calcaneal fractures risks injury to the medial neurovascular structures: a cadaveric description
Aim: There is a risk of iatrogenic injury to the soft tissues of the calcaneus and this study assesses the risk of injury to these structures in circular frame calcaneal fracture fixation.
Materials and Methods: After olive tip wires were inserted, an L-shaped incision on the lateral and medial aspects of 5 formalin fixed cadaveric feet was performed to expose the underlying soft tissues. The calcaneus was divided into zones corresponding to high, medium and low risk using a grading system.
Results: Structures at high risk included the posterior tibial artery, posterior tibial vein and posterior tibial nerve on the medial aspect. Soft tissue structures on the lateral side that were shown to be at lower risk of injury were the small saphenous vein and the sural nerve and the tendons of fibularis longus and fibularis brevis.
Conclusion: The lateral surface of the calcaneus provides a lower risk area for external fixation. The risk of injury to significant soft tissues using a circular frame fixation approach has been shown to be greater on the medial aspect.
Clinical Relevance: This study highlights the relevant anatomical relations in circular frame fixation for calcaneal fractures to minimize damage to these structures
Role of Lactobacilli in Flavour Development of Cheddar Cheese.
End of Project ReportCheddar cheese is a complex microbial ecosystem. The internal
cheese environment, in particular of hard and semi-hard cheeses, is
not conducive to the growth of many microorganisms.
At the beginning of ripening the dominant microorganisms are the
starter bacteria which are present at high levels (~109/g). However,
during ripening, non-starter lactic acid bacteria (NSLAB) grow from
relatively low levels (<103/g) at the beginning of ripening, to 108/g
within 6 - 8 weeks. Other bacteria, e.g. enterococci and staphylococci,
may also be present but in much lower numbers.
In a previous study of mature and extra mature Cheddar cheeses from
different manufacturers (see End of Project Report No. 1), it was
found that the NSLAB population was dominated by strains of Lb.
paracasei. However, their contribution to cheese flavour and their
source(s) are still unclear, nor is it known if the NSLAB flora is unique
to each plant. Hence, understanding the growth of this group of
organisms in cheese is a key to defining their role in flavour
development.
The biochemistry of flavour development in cheese is poorly
understood. For most cheese varieties, including Cheddar,
proteolysis, which results in the accumulation of free amino acids, is
of vital importance for flavour development. Increasing evidence
suggests that the main contribution of amino acids is as substrates for
the development of more complex flavour and aroma compounds.
The manner by which such compounds are generated in cheese is
currently the focus of much research.
Starter bacteria have been shown to contain a range of enzymes
capable of facilitating the conversion of amino acids to potential
flavour compounds. However, the potential of lactobacilli (NSLAB) to
produce similar enzymes has only recently been investigated. Hence, although, it is generally accepted that the cheese starter flora
is the primary defining influence on flavour development, the
contribution of NSLAB is also considered significant.
The objectives of these studies were:
- to develop a greater understanding of the behaviour of NSLAB in
cheese, and
- to identify suitable strains, and other cheese bacteria, to be used as
starter adjuncts for flavour improvement.Department of Agriculture, Food and the Marin
Differential Expression of Immune Response Genes in Steller Sea Lions (\u3ci\u3eEumetopias jubatus\u3c/i\u3e): An Indicator of Ecosystem Health?
Characterization of the polygenic and polymorphic features of the Steller sea lion major histocompatibility complex (MHC) provides an ideal window for evaluating immunologic vigor of the population and identifying emergence of new genotypes that reflect ecosystem pressures. MHC genotyping can be used to measure the potential immunologic vigor of a population. However, since ecosystem-induced changes to MHC genotype can be slow to emerge, measurement of differential expression of these genes can potentially provide real-time evidence of immunologic perturbations. MHC DRB genes were cloned and sequenced using peripheral blood mononuclear leukocytes derived from 10 Steller sea lions from southeast Alaska, Prince William Sound, and the Aleutian Islands. Nine unique DRB gene sequences were represented in each of ten animals. MHC DRB gene expression was measured in a subset of six sea lions. Although DRB in genomic DNA was identical in all individuals, relative levels of expressed DRB mRNA was highly variable. Selective suppression of MHC DRB genes could be indicative of geographically disparate environmental pressures, thereby serving as an immediate and sensitive indicator of population and ecosystem health
Analysis of continuous glucose tracking data in people with type 1 diabetes after COVID-19 vaccination reveals unexpected link between immune and metabolic response, augmented by adjunctive oral medication
Introduction: The COVID-19 vaccination programme is under way worldwide. Anecdotal evidence is increasing that some people with type 1 diabetes mellitus (T1DM) experience temporary instability of blood glucose (BG) levels post-vaccination which normally settles within 2-3 days. We report an analysis of BG profiles of 20 individuals before/after vaccination. Methods: We examined the BG profile of 20 consecutive adults (18 years of age or more) with T1DM using the FreeStyle Libre flash glucose monitor in the period immediately before and after COVID-19 vaccination. The primary outcome measure was percentage (%) BG readings in the designated target range 3.9-10 mmmol/L as reported on the LibreView portal for 7 days prior to the vaccination (week −1) and the 7 days after the vaccination (week +1). Results: There was a significant decrease in the %BG on target following the COVID-vaccination for the 7 days following vaccination (mean 45.2% ± SE 4.2%) vs pre-COVID-19 vaccination (mean 52.6% ± SE 4.5%). This was mirrored by an increase in the proportion of readings in other BG categories 10.1%-13.9%/≥14%. There was no significant change in BG variability in the 7days post-COVID-19 vaccination. This change in BG proportion on target in the week following vaccination was most pronounced for people taking Metformin/Dapagliflozin+basal-bolus insulin (−23%) vs no oral hypoglycaemic agents (−4%), and median age <53 vs ≥53 years (greater reduction in %BG in target for older individuals (−18% vs −9%)). Conclusion: In T1DM, we have shown that COVID-19 vaccination can cause temporary perturbation of BG, with this effect more pronounced in patients talking oral hypoglycaemic medication plus insulin, and in older individuals. This may also have consequences for patients with T2DM who are currently not supported by flash glucose monitoring
Vortex formation with a snapping shrimp claw
Snapping shrimp use one oversized claw to generate a cavitating high speed water jet for hunting, defence and communication. This work is an experimental investigation about the jet generation. Snapping shrimp (Alpheus-bellulus) were investigated by using an enlarged transparent model reproducing the closure of the snapper claw. Flow inside the model was studied using both High-Speed Particle Image Velocimetry (HS-PIV) and flow visualization. During claw closure a channel-like cavity was formed between the plunger and the socket featuring a nozzle-type contour at the orifice. Closing the mechanism led to the formation of a leading vortex ring with a dimensionless formation number of approximate ΔT*≈4. This indicates that the claw might work at maximum efficiency, i.e. maximum vortex strength was achieved by a minimum of fluid volume ejected. The subsequent vortex cavitation with the formation of an axial reentrant jet is a reasonable explanation for the large penetration depth of the water jet. That snapping shrimp can reach with their claw-induced flow. Within such a cavitation process, an axial reentrant jet is generated in the hollow cylindrical core of the cavitated vortex that pushes the front further downstream and whose length can exceed the initial jet penetration depth by several times
Ventricular Tachyarrhythmias after Cardiac Arrest in Public versus at Home
Background
The incidence of ventricular fibrillation or pulseless ventricular tachycardia as the first recorded rhythm after out-of-hospital cardiac arrest has unexpectedly declined. The success of bystander-deployed automated external defibrillators (AEDs) in public settings suggests that this may be the more common initial rhythm when outof-hospital cardiac arrest occurs in public. We conducted a study to determine whether the location of the arrest, the type of arrhythmia, and the probability of survival are associated.
Methods
Between 2005 and 2007, we conducted a prospective cohort study of out-of-hospital cardiac arrest in adults in 10 North American communities. We assessed the frequencies of ventricular fibrillation or pulseless ventricular tachycardia and of survival to hospital discharge for arrests at home as compared with arrests in public.
Results
Of 12,930 evaluated out-of-hospital cardiac arrests, 2042 occurred in public and 9564 at home. For cardiac arrests at home, the incidence of ventricular fibrillation or pulseless ventricular tachycardia was 25% when the arrest was witnessed by emergency-medical-services (EMS) personnel, 35% when it was witnessed by a bystander, and 36% when a bystander applied an AED. For cardiac arrests in public, the corresponding rates were 38%, 60%, and 79%. The adjusted odds ratio for initial ventricular fibrillation or pulseless ventricular tachycardia in public versus at home was 2.28 (95% confidence interval [CI], 1.96 to 2.66; P\u3c0.001) for bystanderwitnessed arrests and 4.48 (95% CI, 2.23 to 8.97; P\u3c0.001) for arrests in which bystanders applied AEDs. The rate of survival to hospital discharge was 34% for arrests in public settings with AEDs applied by bystanders versus 12% for arrests at home (adjusted odds ratio, 2.49; 95% CI, 1.03 to 5.99; P=0.04).
Conclusions
Regardless of whether out-of-hospital cardiac arrests are witnessed by EMS personnel or bystanders and whether AEDs are applied by bystanders, the proportion of arrests with initial ventricular fibrillation or pulseless ventricular tachycardia is much greater in public settings than at home. The incremental value of resuscitation strategies, such as the ready availability of an AED, may be related to the place where the arrest occurs. (Funded by the National Heart, Lung, and Blood Institute and others.
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