The analgesic effect of a popliteal plexus blockade after total knee arthroplasty: A feasibility study

INTRODUCTION

An obturator nerve block (ONB) and a femoral triangle block (FTB) provide effective analgesia after total knee arthroplasty (TKA) without impeding the ambulation, although the ONB produces motor blockade of the hip adductor muscles. The popliteal plexus (PP) in the popliteal fossa is formed by contribution from the tibial nerve and the posterior obturator nerve, innervating intraarticular genicular structures and the posterior capsule of the knee. We hypothesised that a popliteal plexus block (PPB) as a supplement to an FTB would reduce pain after TKA without anaesthetising motor branches from the sciatic nerve in the popliteal fossa.

AIM

To assess the analgesic effect of adding a PPB to an FTB in 10 subjects with significant pain after TKA.

METHODS

All subjects underwent unilateral TKA with spinal anaesthesia and received an FTB. The cutaneous sensation and the postoperative pain were assessed. The primary outcome was the proportion of subjects with pain above numeric rating scale (NRS) 3 followed by a reduction to NRS 3 or below after conducting a PPB.

RESULTS

Ten subjects with a median pain of NRS 5.5 (interquartile range [IQR] 4-8) after unilateral TKA received a PPB. All 10 subjects experienced a reduction in pain to NRS 3 or below (NRS 1.5 [IQR 0-3]) within a mean time of 8.5 (95% CI 6.8-10.2) minutes. Three subjects were completely pain free after the PPB. The ankle muscle strength was not affected.

CONCLUSIONS

The PPB provided effective pain relief without affecting the ankle muscle strength in all 10 subjects with significant pain after TKA and an FTB.

A molecular Pathway Analysis Stresses the Role of Inflammation Towards Cognition in Schizophrenia

Background

Cognitive processes are impaired in Schizophrenia (SKZ). The nature of such impairment escapes definition.

Aim

Identification of a genetic profile at risk of cognitive impairment.

Object

Identifying a molecular pathways enriched for mutations associated with cognitive impairment.

Methods

Seven hundred and sixty-five individuals from the CATIE, M = 556, mean age = 40.93 ± 11.03 were included. Verbal memory was outcome. R and Plink served for the analyses. Inflation factor was controlled by lambda values. Input for the pathway analysis were SNPs associated with outcome (P < 0.05) genomewide.

Results

Gender (male, P = 2.34e–05;t = –4.26) and years of education (P = 1.57e–03;t = 6.502) were associated with verbal memory. Inflammation and oxidation were associated with outcome (Table 1, adj_P < 0.01).

Conclusions

Being male and poorly educated were associated with poorer verbal memory. Inflammation and the arachidonic acid pathway were enriched in mutations associated with poorer verbal memory. This finding is in line with previous reports [1,2,3].

Dynamics of field-driven population inversion in a confined colloidal mixture

We study, using Langevin dynamics simulations, the change in composition of a binary colloidal mixture confined in a finite-length channel, induced by an external field. The field-induced transition from a near-bulk composition to an inverted population is studied as a function of time, for different field strengths and system parameters. For state points corresponding to reversible field cycles, the cyclic filling and emptying of the channel by the minority species are compared. Extrapolation of the physical relaxation times to the colloidal regime is performed through a series of simulations at increasing value of the damping parameter. For state points at which the mixture is unstable at zero field, reproducible irreversible cycles are illustrated. For reversible field cycles, the scaling with the particles size of the characteristic cycling time is discussed.

Single-dose intravenous iron infusion or oral iron for treatment of fatigue after postpartum haemorrhage: a randomized controlled trial

BACKGROUND AND OBJECTIVES

To evaluate the clinical efficacy of a single-dose intravenous infusion of iron isomaltoside compared with current treatment practice with oral iron measured by physical fatigue in women after postpartum haemorrhage.

MATERIALS AND METHODS

Single-centre, open-label, randomized controlled trial. Participants received intravenous iron (n = 97) or oral iron (n = 99), and completed the Multidimensional Fatigue Inventory and Edinburgh Postnatal Depression Scale, and haematological and iron parameters were measured. Primary outcome was the aggregated change in physical fatigue score from baseline to 12 weeks postpartum.

RESULTS

The difference in physical fatigue score was -0·97 (95% CI: -1·65; -0·28, P = 0·006) in favour of intravenous iron, but did not meet the predefined difference of 1·8. Across visits, we found statistically significant differences in fatigue and depression scores, as well as in haematological and iron parameters, all in favour of intravenous iron. There were no serious adverse reactions.

CONCLUSION

A single dose of intravenous iron was associated with a statistically significant reduction in aggregated physical fatigue within 12 weeks after postpartum haemorrhage compared to standard medical care with oral iron below the prespecified criteria of clinical superiority. As patient-reported outcomes improved significantly and intravenous iron resulted in a fast hematopoietic response without serious adverse reactions, intravenous iron may be a useful alternative after postpartum haemorrhage if oral iron is not absorbed or tolerated.

Single-dose intravenous iron infusion versus red blood cell transfusion for the treatment of severe postpartum anaemia: a randomized controlled pilot study

BACKGROUND AND OBJECTIVES

There are no randomized trials comparing intravenous iron to RBC transfusion for the treatment of severe postpartum anaemia. The objectives of this study were to evaluate the feasibility of randomizing women with severe postpartum anaemia secondary to postpartum haemorrhage to RBC transfusion or intravenous iron, and to describe patient-reported outcomes, and haematological and iron parameters.

MATERIALS AND METHODS

Women with a postpartum haemorrhage exceeding 1000 ml and an Hb between 5·6 and 8·1 g/dl were randomized to 1500 mg of intravenous iron (n = 7) isomaltoside or RBC transfusion (n = 6). Participants completed the Multidimensional Fatigue Inventory and Edinburgh Postnatal Depression Scale, and blood samples were drawn at inclusion, daily during the first week and at weeks 3, 8 and 12.

RESULTS

We screened 162 women and included 13 (8%). There was no significant difference between groups in fatigue or depression scores. RBC transfusion was associated with a higher Hb on day 1, inhibition of reticulocytosis during the first week and low iron levels. Intravenous iron was associated with increased reticulocytosis during the first week, repleted iron stores and a higher Hb in weeks 3-12.

CONCLUSION

This pilot study shows that intravenous iron could be an attractive alternative to RBC transfusion in severe postpartum anaemia, and that a larger trial is needed and feasible.

Toll-like receptor 2 and 4 induced interleukin-19 dampens immune reactions and associates inversely with spondyloarthritis disease activity

Spondyloarthritis (SpA) is a group of immune mediated inflammatory diseases affecting joints, gut, skin and entheses. The inflammatory process involves activation of Toll-like receptor (TLR)-2 and TLR-4 and production of cytokines and chemokines such as monocyte chemoattractant protein 1 (CCL2/MCP-1). This proinflammatory chemokine recruits monocytes to sites of inflammation and is central in the development of several immune-mediated inflammatory diseases. Interleukin (IL)-19 is a member of the IL-10 family of cytokines. IL-19-deficient mice are more susceptible to innate-mediated colitis and develop more severe inflammation in response to injury. In this work, we studied inducers of IL-19 production and effect of IL-19 on the production of CCL2/MCP-1 and proinflammatory cytokines in peripheral blood mononuclear cells (PBMCs) from healthy controls (HCs) and in PBMCs and synovial fluid mononuclear cells (SFMCs) from SpA patients. Further, we measured IL-19 in plasma from HCs and in plasma and synovial fluid from SpA patients. Constitutive IL-19 expression was present in both PBMCs and SFMCs and the secretion of IL-19 was increased by TLR-2 and TLR-4 ligands. Neutralizing IL-19 in HC PBMCs and SpA SFMCs resulted in increased production of CCL-2/MCP-1. IL-19 concentrations were decreased in synovial fluid compared with plasma and associated inversely with disease activity in SpA. SpA SFMCs produced less IL-19 in response to LPS compared with HC PBMCs. These findings indicate that IL-19 production is diminished in SpA. Taken together, impaired IL-19 control of the innate immune system might be involved in the pathogenesis of SpA.

Efficacy and safety of nicoboxil/nonivamide ointment for the treatment of acute pain in the low back - A randomized, controlled trial

Background

Until now, nonivamide/nicoboxil ointment has not been tested in a randomized trial for the treatment of acute non‐specific low back pain.

Methods

This phase III randomized, double‐blind, active‐ and placebo‐controlled, multi‐centre trial investigated efficacy, safety and tolerability of topical nicoboxil 2.5%/nonivamide 0.4% for treatment of acute non‐specific low back pain [primary endpoint: pain intensity (PI) difference between pre‐dose baseline and 8 h after the first application].

Results

Patients (n = 805), 18–74 years of age were treated for up to 4 days with nicoboxil 2.5%/nonivamide 0.4%, nicoboxil 2.5%, nonivamide 0.4% or placebo ointment. Pre‐dose baseline pain intensity (6.6 on a 0‐ to 10‐point numerical rating scale) was reduced by 1.049 points with placebo, by 1.428 points with nicoboxil, by 2.252 points with nonivamide and by 2.410 points with nicoboxil/nonivamide after 8 h (p < 0.0001 for nicoboxil/nonivamide vs. placebo, nicoboxil; p = 0.4171 for nicoboxil/nonivamide vs. nonivamide). At the end of treatment, the combination provided more pronounced PI reduction (3.540 points) compared with nicoboxil (2.371, p < 0.0001), nonivamide (3.074, p = 0.0259) and placebo (1.884, p < 0.0001). Low back mobility scores on Day 1 were better for the combination compared with all other treatments (p < 0.044); on Day 2–4, scores were better than for placebo and nicoboxil (p < 0.003). Patients assessed efficacy of the combination as greater than of the comparators (p ≤ 0.0129). All treatments were tolerated well. No treatment‐related serious adverse events were reported.

Conclusion

Nicoboxil/nonivamide ointment is an effective, well‐tolerated medication for the treatment of acute non‐specific low back pain.

Communication: Kinetic and pairing contributions in the dielectric spectra of electrolyte solutions

In the late 1970s, Hubbard and Onsager predicted that adding salt to a polar solution would result in a reduced dielectric permittivity that arises from the unexpected tendency of solvent dipoles to align opposite to the applied field. Here we develop a novel non-equilibrium molecular dynamics simulation approach to determine this decrement accurately. Using a thermodynamic consistent all-atom force field we show that for an aqueous solution containing sodium chloride around 4.8 mol/l, this effect accounts for 12% of the total dielectric permittivity. The dielectric decrement can be strikingly different if a less accurate force field for the ions is used. Using the widespread GROMOS parameters, we observe in fact an increment of the dielectric permittivity rather than a decrement, caused by ion pairing and introduced by a too low dispersion force.

Computing the Coulomb interaction in inhomogeneous dielectric media via a local electrostatics lattice algorithm

The local approach to computing electrostatic interactions proposed by Maggs and adapted by Rottler and Pasichnyk for molecular-dynamics simulations is extended to situations where the dielectric background medium is inhomogeneous. We furthermore correct a problem of the original algorithm related to the correct treatment of the global dipole moment, provide an error estimate for the accuracy of the algorithm, and suggest a different form of the treatment of the self-energy problem. Our implementation is highly scalable on many cores, and we have validated and compared its performance against theoretical predictions and simulation data obtained by other algorithmic approaches.

How to Convert SPME to P3M: Influence Functions and Error Estimates

We demonstrate explicitly how the two seemingly different particle mesh Ewald methods, the smooth particle mesh Ewald (SPME) and the particle-particle particle mesh (P3M), can be mathematically transformed into each other. This allows us in particular to convert the error estimate of the P3M method in the energy-conserving scheme (also known as "P3M with analytic differentiation") into an error estimate for the SPME method, via a simple change of the lattice Green function. Our error estimate is valid for any values of the SPME parameters (mesh size, spline interpolation order, Ewald splitting parameter, real-space cutoff distance), including odd orders of splines. The problem with the self-forces is avoided thanks to an analytical formula that allows to subtract them directly within the particle mesh calculation. Plots of the accuracy of the SPME forces are provided for a wide range of parameter values. The main use of the error estimate is to allow a simulation program to scan quickly the multidimensional parameter space to find the best set of parameters to achieve a target accuracy at the smallest computational cost. As a byproduct, we show how a SPME code can be transformed into a P3M version by changing a few lines of code. We demonstrate also that the P3M lattice Green function can be approximated by a closed form expression, computable on-the-fly, that provides essentially the same accuracy as the full function.

Severe postpartum haemorrhage and mode of delivery: a retrospective cohort study

OBJECTIVE

To examine the association between intended mode of delivery and severe postpartum haemorrhage.

DESIGN

A retrospective cohort study.

SETTING

Material from a nationwide study in Denmark.

POPULATION

Danish women giving birth in 2001-08.

METHODS

We compared use of red blood cell transfusion by intended mode of delivery in the total population (n = 382 266), in low-risk nulliparous women (n = 147 132) and in women with a previous caesarean delivery (n = 25 156).

MAIN OUTCOME MEASURE

Red blood cell transfusion within 7 days of delivery.

RESULTS

In the total population the crude transfusion rates for women with planned caesarean delivery and intended vaginal delivery were 2.24 and 1.75%. After adjustment for maternal age, body mass index, birthweight, smoking, parity, number of infants and previous caesarean delivery, the risk of red blood cell transfusion was significantly lower in women with planned caesarean delivery compared with intended vaginal delivery (odds ratio 0.82; 95% CI 0.73-0.92; P < 0.01). In low-risk nulliparous women and in women with a previous caesarean delivery the transfusion rates were lower for planned caesarean delivery compared with intended vaginal delivery before and after adjustment.

CONCLUSION

Compared with intended vaginal delivery, planned caesarean delivery was associated with a reduced risk of severe postpartum haemorrhage indicated by use of red blood cell transfusion.

Effects of rose hip intake on risk markers of type 2 diabetes and cardiovascular disease: a randomized, double-blind, cross-over investigation in obese persons

BACKGROUND/OBJECTIVES:

In studies performed in mice, rose hip powder has been shown to both prevent and reverse high-fat diet-induced obesity and glucose intolerance as well as reduce plasma levels of cholesterol. The aim of this study was to investigate whether daily intake of rose hip powder over 6 weeks exerts beneficial metabolic effects in obese individuals.

SUBJECTS/METHODS:

A total of 31 obese individuals with normal or impaired glucose tolerance were enrolled in a randomized, double-blind, cross-over study in which metabolic effects of daily intake of a rose hip powder drink over 6 weeks was compared with a control drink. Body weight, glucose tolerance, blood pressure, blood lipids and markers of inflammation were assessed in the subjects.

RESULTS:

In comparison with the control drink, 6 weeks of daily consumption of the rose hip drink resulted in a significant reduction of systolic blood pressure (−3.4% P=0.021), total plasma cholesterol (−4.9% P=0.0018), low-density lipoprotein (LDL) cholesterol (−6.0% P=0.012) and LDL/HDL ratio (−6.5% P=0.041). The Reynolds risk assessment score for cardiovascular disease was decreased in the rose hip group compared with the control group (−17% P=0.007). Body weight, diastolic blood pressure, glucose tolerance, and plasma levels of high-density lipoprotein (HDL) cholesterol, triglycerides, incretins and markers of inflammation did not differ between the two groups.

CONCLUSIONS:

Daily consumption of 40 g of rose hip powder for 6 weeks can significantly reduce cardiovascular risk in obese people through lowering of systolic blood pressure and plasma cholesterol levels.

Hydrogen Neutralization of Chalcogen double donor Centers in Single-Crystal Silicon

Chalcogen (S,Se,Te) -doped silicon samples were hydrogen neutralized by different passivation techniques. The electrically active double-donor densities were determined by DLTS measurements. DLTS spectra reveal that both donor levels recover simultaneously. The activation energy for re-activation of neutralized isolated and pure pair sulphur double-donors is Ea(So/+) = 2,13 ± 0,15 eV and Ea(S2o/+) = 2,1 ± 0,15 eV, respectively.

A low glycaemic diet improves oral glucose tolerance but has no effect on β-cell function in C57BL/6J mice

AIM

Clinical studies have suggested a role for dietary glycaemic index (GI) in body weight regulation and diabetes risk. Here, we investigated the long-term metabolic effects of low and high glycaemic diets using the C57BL/6J mouse model.

METHODS

Female C57BL/6J mice were fed low or high glycaemic starch in either low-fat or medium-fat diets for 22 weeks. Oral and intravenous glucose tolerance tests were performed to investigate the effect of the experimental diets on glucose tolerance and insulin resistance.

RESULTS

In this study, a high glycaemic diet resulted in impaired oral glucose tolerance compared to a low glycaemic diet. This effect was more pronounced in the group fed a medium-fat diet, suggesting that a lower dietary fat content ameliorates the negative effect of a high glycaemic diet. No effect on body weight or body fat content was observed in either a low-fat diet or a medium-fat diet. Static incubation of isolated islets did not show any differences in basal (3.3 mM glucose) or glucose-stimulated (8.6 and 16.7 mM glucose) insulin secretion between mice fed a low or high glycaemic diet.

CONCLUSION

Together, our data suggest that the impaired glucose tolerance seen after a high glycaemic diet is not explained by altered β-cell function.

Probiotics lower plasma glucose in the high-fat fed C57BL/6J mouse

Today, the gut microbiota is considered a key organ in host nutritional metabolism and recent data have suggested that alterations in gut microbiota contribute to the development of type 2 diabetes and obesity. Accordingly, a whole range of beneficial effects relating to inflammation and gut health have been observed following administration of probiotics to both humans and different animal models. The objective of this study was to evaluate the metabolic effects of an oral probiotic supplement, Lactobacillus plantarum DSM 15313, to high-fat diet (HFD) fed C57BL/6J mice, a model of human obesity and early diabetes. The mice were fed the experimental diets for 20 weeks, after which the HFD had induced an insulin-resistant state in both groups compared to the start of the study. The increase in body weight during the HFD feeding was higher in the probiotic group than in the control group, however, there were no significant differences in body fat content. Fasting plasma glucose levels were lower in the group fed the probiotic supplement, whereas insulin and lipids were not different. Caecal levels of short-chain fatty acids were not significantly different between the groups. An oral glucose tolerance test showed that the group fed probiotics had a significantly lower insulin release compared to the control group, although the rate of glucose clearance was not different. Taken together, these data indicate that L. plantarum DSM 15313 has anti-diabetic properties when fed together with an HFD.

Ensemble inequivalence in single-molecule experiments

In bulk systems the calculation of the main thermodynamic quantities leads to the same expectation values in the thermodynamic limit, regardless of the choice of the statistical ensemble. Single linear molecules can be still regarded as statistical systems, where the thermodynamic limit is represented by infinitely long chains. The question of equivalence between different ensembles is not at all obvious and has been addressed in the literature, with sometimes contradicting conclusions. We address this problem by studying the scaling properties of the ensemble difference for two different chain models as a function of the degree of polymerization. By characterizing the scaling behavior of the difference between the isotensional (Gibbs) and isometric (Helmholtz) ensembles in the transition from the low-stretching to the high-stretching regime, we show that ensemble equivalence cannot be reached for macroscopic chains in the low force regime, and we characterize the transition from the inequivalence to the equivalence regime.

Phosphorylation of the oestrogen receptor alpha at serine 305 and prediction of tamoxifen resistance in breast cancer

Phosphorylation of oestrogen receptor alpha at serine 305 (ERalphaS305-P) induces tamoxifen resistance in experimental studies, but does not influence response to other endocrine agents, such as fulvestrant. We evaluated ERalphaS305-P using immunohistochemistry in 377 breast carcinomas from premenopausal participants of a randomized trial (n=248) and patients with advanced disease (n=129). Among the premenopausal patients, adjuvant tamoxifen improved recurrence-free survival (RFS) for ERalphaS305-P-negative tumours (multivariate HR=0.53, 95% CI 0.32-0.86, p=0.010), but not for ERalphaS305-P-positive tumours (multivariate HR=1.01, 95% CI 0.33-3.05, p=0.99) (interaction p=0.131). Notably, ERalphaS305-P was not significantly associated with RFS in patients not treated with tamoxifen (multivariate HR=0.64, 95% CI 0.30-1.37, p=0.248), indicating that ERalphaS305-P is a marker for treatment outcome rather than tumour progression. Given the direct experimental link between ERalphaS305-P and tamoxifen resistance and these first clinical data suggesting that premenopausal patients with ERalphaS305-P-positive breast cancer are resistant to adjuvant tamoxifen, further research is encouraged to study whether alternative endocrine treatment should be considered for this subgroup.

A beta cell-specific knockout of hormone-sensitive lipase in mice results in hyperglycaemia and disruption of exocytosis

AIMS/HYPOTHESIS

The enzyme hormone-sensitive lipase (HSL) is produced and is active in pancreatic beta cells. Because lipids are known to play a crucial role in normal control of insulin release and in the deterioration of beta cell function, as observed in type 2 diabetes, actions of HSL in beta cells may be critical. This notion has been addressed in different lines of HSL knockout mice with contradictory results.

METHODS

To resolve this, we created a transgenic mouse lacking HSL specifically in beta cells, and characterised this model with regard to glucose metabolism and insulin secretion, using both in vivo and in vitro methods.

RESULTS

We found that fasting basal plasma glucose levels were significantly elevated in mice lacking HSL in beta cells. An IVGTT at 12 weeks revealed a blunting of the initial insulin response to glucose with delayed elimination of the sugar. Additionally, arginine-stimulated insulin secretion was markedly diminished in vivo. Investigation of the exocytotic response in single HSL-deficient beta cells showed an impaired response to depolarisation of the plasma membrane. Beta cell mass and islet insulin content were increased, suggesting a compensatory mechanism, by which beta cells lacking HSL strive to maintain normoglycaemia.

CONCLUSIONS/INTERPRETATION

Based on these results, we suggest that HSL, which is located in close proximity of the secretory granules, may serve as provider of a lipid-derived signal essential for normal insulin secretion.

Shear effects on crystal nucleation in colloidal suspensions

Extensive two-dimensional Langevin dynamics simulations are used to determine the effect of steady shear flows on the crystal nucleation kinetics of charge stabilized colloids and colloids whose pair potential possess an attractive shallow well of a few k_{B}T 's (attractive colloids). Results show that in both types of systems small amounts of shear speeds up the crystallization process and enhances the quality of the growing crystal significantly. Moderate shear rates, on the other hand, destroy the ordering in the system. The very high shear rate regime where a reentering transition to the ordered state could exist is not considered in this work. In addition to the crystal nucleation phenomena, the analysis of the transport properties and the characterization of the steady state regime under shear are performed.

Interactions of like-charged rods at low temperatures: analytical theory vs. simulations

We investigate a system consisting of two like-charged infinitely long rods and neutralizing counterions at low temperatures, using both analytic theory and simulations. With some reasonable approximations we can analytically solve for several ground-state structures of the model, starting with states where all counterions are lined up in the gap between the rods, over planar configurations, where the counterions are divided up into a fraction which resides between the rods, and counterions which are located on the outer surfaces, up to configurations which cover the full rod surfaces. Using parallel tempering simulations, we are able to study the system over a wide range of temperatures. At low temperatures we find good agreement with our T = 0 results. At higher temperatures, the strong coupling (SC) theory delivers qualitatively better results. We furthermore demonstrate that for the SC theory and our ground-state approximations to yield quantitative agreement, three parameters are required to be large, the strong-coupling parameter, the Rouzina-Bloomfield parameter, and the ratio of the average distance of the counterions to the radius of the rods. In the case of the latter ratio being small, our T = 0 results show better agreement with the simulation data at very low temperatures.

Simulation of charge reversal in salty environments: giant overcharging?

We have performed MD simulations of a highly charged colloid in a solution of 3:1 and additional 1:1 salt. The dependency of the colloid's inverted charge on the concentration of the additional 1:1 salt has been studied. Most theories predict, that the inverted charge increases when the concentration of monovalent salt grows, up to what is called giant overcharging, while experiments and simulational studies observe the opposite. Our simulations agree with the experimental findings and shed light onto the weaknesses of the theories.

Oestrogen receptors alpha and beta show different associations to clinicopathological parameters and their co-expression might predict a better response to endocrine treatment in breast cancer

AIMS

The majority of all breast cancers are hormone responsive, traditionally defined by the expression of oestrogen receptor (ER) alpha and/or progesterone receptors. In contrast to ERalpha, the clinical significance of the relatively recently identified ERbeta is still unclear. This study aimed to define the relationship between ERbeta and clinicopathological parameters in a mixed cohort of breast cancer and, furthermore, to investigate the impact of ERbeta expression on disease outcome.

METHODS

The immunohistochemical expression of ERalpha and ERbeta was analysed in tissue microarrays containing a total number of 512 tumours with all incident breast cancers diagnosed at the Malmö University Hospital between 1988 and 1992.

RESULTS

78% of the tumours were ERalpha positive and 50% were ERbeta positive. ERbeta correlated positively with ERalpha (p = 0.001). In contrast to ERalpha, ERbeta was not associated with any important clinicopathological variables. Furthermore, no overall prognostic significance could be demonstrated for ERbeta. In the ERalpha-positive subgroup, however, a low expression of ERbeta correlated with a decreased disease-free survival in patients receiving endocrine treatment (p = 0.003).

CONCLUSIONS

Although interrelated, ERalpha and ERbeta seem to be differentially associated to clinicopathological parameters, and this would support the fact that they might have different functions in vivo. Furthermore, ERbeta might be a predictive marker of response to endocrine therapy, although this needs to be confirmed in additional studies, preferably randomised trials.

Tail-induced attraction between nucleosome core particles

We study a possible electrostatic mechanism underlying the compaction of DNA inside the nuclei of eucaryotes: the tail-bridging effect between nucleosomes, the fundamental DNA packaging units of the chromatin complex. As a simple model of the nucleosome we introduce the eight-tail colloid, a charged sphere with eight oppositely charged, flexible, grafted chains that represent the terminal histone tails. We show that our complexes attract each other via the formation of chain bridges and contrast this to the effect of attraction via charge patches. We demonstrate that the attraction between eight-tail colloids can be tuned by changing the fraction of charged monomers on the tails. This suggests a physical mechanism of chromatin compaction where the degree of DNA condensation is controlled via biochemical means, namely the acetylation and deacetylation of lysines in the histone tails.

The hormone-sensitive lipase C-60G promoter polymorphism is associated with increased waist circumference in normal-weight subjects

OBJECTIVE

Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from triglyceride stores in adipocytes. The aim of the present study was to investigate the role of the HSL gene promoter variant C-60G, a polymorphism which previously has been associated with reduced promoter activity in vitro, in obesity and type 2 diabetes.

DESIGN

We genotyped two materials consisting of obese subjects and non-obese controls, one material with offspring-parents trios, where the offspring was abdominally obese and one material with trios, where the offspring had type 2 diabetes or impaired glucose homeostasis. HSL promoter containing the HSL C-60G G-allele was generated and tested against a construct with the C-allele in HeLa cells and primary rat adipocytes. HSL mRNA levels were quantified in subcutaneous and visceral fat from 33 obese subjects.

RESULTS

We found that the common C-allele was associated with increased waist circumference and WHR in lean controls, but there was no difference in genotype frequency between obese and non-obese subjects. There was a significant increased transmission of C-alleles to the abdominally obese offspring but no increased transmission of C-alleles was observed to offspring with impaired glucose homeostasis. The G-allele showed reduced transcription in HeLa cells and primary rat adipocytes. HSL mRNA levels were significantly higher in subcutaneous compared to visceral fat from obese subjects.

CONCLUSION

The HSL C-60G polymorphism is associated with increased waist circumference in non-obese subjects.

Der freie und gestielte Muskeltransfer als Therapieoption in der urologischen Chirurgie

Various demands of reconstruction define restoration technique. The basic principle involves optimal anatomical and functional reconstruction with concurrent minimal donor-site morbidity. Dependent on the aetiology of the defect, there are various reconstructive possibilities available for obtaining an optimal result. An immediate single stage reconstruction, with the best possible result for the individual patient as the primary consideration, can be carried out by interdisciplinary teams. In this overview, the most common indications and principles of flap choice are presented in relation to the reconstructive requirements necessary for early rehabilitation of the patient or the earlier start of necessary adjuvant therapy.

Computer simulations of the structure of colloidal ferrofluids

The structure of a ferrofluid under the influence of an external magnetic field is expected to become anisotropic due to the alignment of the dipoles into the direction of the external field, and subsequently to the formation of particle chains due to the attractive head to tail orientations of the ferrofluid particles. Knowledge about the structure of a colloidal ferrofluid can be inferred from scattering data via the measurement of structure factors. We have used molecular-dynamics simulations to investigate the structure of both monodispersed and polydispersed ferrofluids. The results for the isotropic structure factor for monodispersed samples are similar to previous data by Camp and Patey that were obtained using an alternative Monte Carlo simulation technique, but in a different parameter region. Here we look in addition at bidispersed samples and compute the anisotropic structure factor by projecting the q vector onto the XY and XZ planes separately, when the magnetic field was applied along the z axis. We observe that the XY-plane structure factor as well as the pair distribution functions are quite different from those obtained for the XZ plane. Further, the two-dimensional structure factor patterns are investigated for both monodispersed and bidispersed samples under different conditions. In addition, we look at the scaling exponents of structure factors. Our results should be of value to interpret scattering data on ferrofluids obtained under the influence of an external field.

Magnetization of polydisperse colloidal ferrofluids: effect of magnetostriction

We exploit magnetostriction in polydisperse ferrofluids in order to generate nonlinear responses and apply a thermodynamical method to derive the desired nonlinear magnetic susceptibility. For an ideal gas, this method has been demonstrated to be in excellent agreement with a statistical method. In the presence of a sinusoidal ac magnetic field, the magnetization of the polydisperse ferrofluid contains higher-order harmonics, which can be extracted analytically by using a perturbation approach. We find that the harmonics are sensitive to the particle distribution and the degree of field-induced anisotropy of the system. In addition, we find that the magnetization is higher in the polydisperse system than in the monodisperse one, as also found by a recent Monte Carlo simulation. Thus, it seems possible to detect the size distribution in a polydisperse ferrofluid by measuring the harmonics of the magnetization under the influence of magnetostriction.

A clinical randomized study on the effects of invasive monitoring on burn shock resuscitation

BACKGROUND

Ever since Charles Baxter's recommendations the standard regime for burn shock resuscitation remains crystalloid infusion at a rate of 4 ml/kg/% burn in the first 24h following the thermal injury. A growing number of studies on invasive monitoring in burn shock, however, have raised a debate regarding the adequacy of this regime. The purpose of this prospective, randomised study was to compare goal-directed therapy guided by invasive monitoring with standard care (Baxter formula) in patients with burn shock.

PATIENTS AND METHODS

Fifty consecutive patients with burns involving more than 20% body surface area were randomly assigned to one of two treatment groups. The control group was resuscitated according to the Baxter formula (4 ml/kg BW/% BSA burn), the thermodilution (TDD) group was treated according to a volumetric preload endpoint (intrathoracic blood volume) obtained by invasive haemodynamic monitoring.

RESULTS

The baseline characteristics of the two treatment groups were similar. Fluid administration in the initial 24h after burn was significantly higher in the TDD treatment group than in the control group (P = 0.0001). The results of haemodynamic monitoring showed no significant difference in preload or cardiac output parameters. Signs of significant intravasal hypovolemia as indicated by subnormal values of intrathoracic and total blood volumes were present in both treatment groups. Mortality and morbidity were independent on randomisation.

CONCLUSION

Burn shock resuscitation due to the Baxter formula leads to significant hypovolemia during the first 48 h following burn. Haemodynamic monitoring results in more aggressive therapeutic strategies and is associated with a significant increase in fluid administration. Increased crystalloid infusion does not improve preload or cardiac output parameters. This may be due to the fact that a pure crystalloid resuscitation is incapable of restoring cardiac preload during the period of burn shock.

A flow cytometric technique for quantification and differentiation of bacteria in bulk tank milk

AIMS

The present study describes a flow cytometric technique for quantification and differentiation of bacteria in bulk tank milk according to the main cause of elevated counts.

METHODS AND RESULTS

A total of 75 Danish bulk tank milk samples exceeding the grading level of 3.0 x 10(4) CFU ml(-1) were examined by both flow cytometry and traditional microbiological analyses. The correlation coefficient (r) between the two methods was 0.71. For the differential analyses of the dominant bacterial populations four different parameters were used to give a species-characteristic pattern. The four parameters were as follows: staining with Oregon Green conjugated wheat germ agglutinin that binds to the cell wall of bacteria, staining with hexidium iodide that binds to all bacterial DNA, the flow cytometric forward scatter and the flow cytometric side scatter. Three regions in the flow cytometric plot were defined: region 1 includes bacteria mainly associated with poor hygiene, region 2 includes psychrotrophic hygiene bacteria and region 3 includes bacteria mainly related to mastitis. The ability of the flow cytometric technique to predict the main cause of elevated bacterial counts on routine samples was examined. Comparing these results with results obtained by traditional microbiological analyses for identification showed that for 81% of the samples the two techniques agreed on the main cause of an elevated bacterial count.

CONCLUSIONS

The ability of the presented flow cytometric technique to enumerate and differentiate bacteria in bulk tank milk according to the main cause of elevated counts was demonstrated.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study described the first step in development of a technique suitable for routine analyses of bulk tank milk samples. A technique indicating the main cause of an elevated count will enable the farmer to eliminate the contamination source within a short time limit.

Acute hyperglycaemia following thermal injury: friend or foe?

INTRODUCTION

Hyperglycaemia and insulin resistance are common in severely burned patients, even if they have not previously had diabetes. Conventionally, hyperglycaemia is considered a part of the hypermetabolic stress response and blood glucose levels up to 215 mg/dl are tolerated before insulin therapy is initiated. Recent studies suggest that hyperglycaemia and insulin resistance are harmful and that correcting blood glucose to normal levels with insulin might improve the prognosis significantly.

STUDY OBJECTIVE

The purpose of this clinical study was to evaluate blood glucose levels in severely burned patients with conventional management and to analyse the association between early hyperglycaemia and clinical outcome.

DESIGN

Clinical, prospective, descriptive study.

PATIENTS

Thirty seven severely burned adults (>25% total body surface area).

INTERVENTIONS

Hyperglycaemia was treated according to conventional clinical practice. This included the infusion of insulin based on a blood glucose level >215 mg/dl and the maintenance of the glucose level between 180 and 200 mg/dl.

MEASUREMENTS AND RESULTS

Measurements of whole-blood glucose were performed at 8, 16, 24, 36 and 48 h after the thermal injury. Additional measurements were performed if indicated. A total of 185 measurements were obtained and significant elevations of blood glucose levels (>140 mg/dl) were found in 108 (64%) of the measurements. Peak blood glucose values exceeded 140 mg/dl in all but three of the patients; however, only 17 patients received insulin treatment during the shock period. The inadequacy of the insulin treatment is shown by the mean glucose values, which exceeded 200 mg/dl in 27% of the patients. Despite a non-significant difference in the extent of burn (P=0.055), patients who died showed significantly higher maximum glucose values than patients who survived the thermal injury (P<0.05). Even though not statistically significant, blood glucose control was poorer in patients who later developed sepsis or acute renal failure (P>0.05). No correlation was found between burned surface area (TBSA) and mean plasma glucose levels during the first 48 h of resuscitation (r=0.12).

CONCLUSION

Hyperglycaemia is very frequent during the resuscitation period of thermal injury and current guidelines for insulin therapy are inadequate to correct plasma glucose to normal levels. As an association between early hyperglycaemia and subsequent mortality seems to exist, more aggressive manoeuvres to reduce blood glucose may be warranted in this group of patients.

Predominant Microflora of Downgraded Danish Bulk Tank Milk

The microflora of downgraded Danish bulk tank milk was examined to identify the main causes of increased microbial counts. Seventy-five representative samples with a microbial count exceeding 3.0 x 10(4) cfu/mL were selected for a more detailed microbial examination. A total of 1237 isolates from these samples were identified. Gram-negative, oxidase-positive bacteria were found in 72% of the samples. Coliforms were found in 20% of the samples, and non-coliforms were found in 49% of the samples. Coryneforms, other gram-positive rods, Lactococcus spp., Micrococcus spp., and coagulase-negative Staphylococcus spp. were found in 28 to 53% of the samples. Bacillus spp., Enterococcus spp., Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus uberis, and yeasts were found in <25% of the samples. Additionally, the isolates were divided into 3 groups, based on the main cause of an elevated microbial count. Microorganisms primarily associated with poor hygiene dominated the microflora in 64% of the samples; bacteria also related to poor hygiene, but in addition associated with growth at low temperatures (psychrotrophic bacteria) dominated the microflora in 28% of the samples; and bacteria mainly associated with mastitis dominated the microflora in 8% of the samples. A bulk tank milk storage period of 48 h instead of 24 h did not affect the proportion of downgraded milk samples and could not be associated with a specific group of microorganisms. Further, no relationship was found between somatic cell counts and the presence of mastitis bacteria.

Molecular mechanisms regulating hormone-sensitive lipase and lipolysis

HSL (hormone-sensitive lipase) is a key enzyme in the mobilization of fatty acids from acylglycerols in adipocytes as well as non-adipocytes. In adipocytes, catecholamines stimulate lipolysis mainly through PKA (protein kinase A)-mediated phosphorylation of HSL and perilipin, a protein coating the lipid droplet. The anti-lipolytic action of insulin is mediated mainly via lowered cAMP levels, accomplished through activation of phosphodiesterase 3B. Phosphorylation of HSL by PKA occurs at three sites, the serines 563, 659 and 660, both in vitro and in primary rat adipocytes. Phosphorylation of Ser-659 and -660 is required for in vitro activation as well as translocation from the cytosol to the lipid droplet, whereas the role of the third PKA site remains elusive. Adipocytes isolated from homozygous HSL-null mice, generated in our laboratory, exhibit completely blunted catecholamine-induced glycerol release and reduced fatty acid release, suggesting the presence of additional, although not necessarily hormone-activatable, triacylglycerol lipase(s). Basal hyperinsulinaemia, release of exaggerated amounts of insulin during glucose challenges and retarded glucose disposal during insulin tolerance tests suggest that HSL-null mice are insulin resistant. Liver, adipose tissue and skeletal muscle appear all to be sites of impaired insulin sensitivity in HSL-null mice.

Hormone-sensitive lipase in skeletal muscle: regulatory mechanisms

AIM

The enzymatic regulation of intramuscular triacylglycerol (TG) breakdown has until recently not been well understood. Our aim was to elucidate the role of hormone-sensitive lipase (HSL), which controls TG breakdown in adipose tissue.

METHODS

Isolated rat muscle as well as exercising humans were studied.

RESULTS

The presence of HSL was demonstrated in all muscle fibre types by Western blotting of muscle fibres isolated by collagenase treatment or after freeze-drying. The content of HSL varies between fibre types, being higher in oxidative than in glycolytic fibres. Analysed under conditions optimal for HSL, neutral lipase activity in muscle can be stimulated by adrenaline as well as by contractions. These increases are abolished by presence of anti-HSL antibody during analysis. Moreover, immunoprecipitation with affinity-purified anti-HSL antibody causes similar reductions in muscle HSL protein concentration and in measured neutral lipase responses to contractions. The immunoreactive HSL in muscle is stimulated by adrenaline via beta-adrenergic activation of protein kinase A (PKA). From findings in adipocytes it is likely that PKA phosphorylates HSL at residues Ser563, Ser659 and Ser660. Contraction probably also enhances muscle-HSL activity by phosphorylation, because the contraction-induced increase in HSL activity is increased by the protein phosphatase inhibitor okadaic acid and reversed by alkaline phosphatase. A novel signalling pathway in muscle by which HSL activity may be stimulated by protein kinase C (PKC) via extracellular signal regulated kinase (ERK) has been demonstrated. In contrast to previous findings in adipocytes, in muscle activation of ERK is not necessary for stimulation of HSL by adrenaline. However, contraction-induced HSL activation is mediated by PKC, at least partly via the ERK pathway. In fat cells ERK is known to phosphorylate HSL at Ser600. So, phosphorylation of different sites may explain that in muscle the effects of contractions and adrenaline on HSL activity are partially additive. In line with the view that the two stimuli act by different mechanisms, training increases the contraction-mediated, but diminishes the adrenaline mediated HSL activation in muscle.

CONCLUSION

The existence and regulation of HSL in skeletal muscle indicate a role of HSL in muscle TG metabolism.

Monitoring free flaps using laser-induced fluorescence of indocyanine green: a preliminary experience

In a prospective, clinical study, the clinical utility of indocyanine green for intraoperative monitoring of free tissue transfer was evaluated. The study comprised 20 surgical patients undergoing elective microsurgical procedures. Indocyanine green angiography was performed intraoperatively, immediately after flap inset, and the operating team was blind to the fluoremetric findings. Thereafter, postoperative monitoring was done exclusively by clinical examination (color, temperature, time for recapillarization, and bleeding after puncture). Final outcome was compared with results of perioperative indocyanine (ICG)-imaging, and classified either as total flap loss, partial flap loss, or successful tissue transplantation. A total of 2 (10%) complications was recorded, and included one partial and one total flap loss. Both complications were detected by intraoperative ICG imaging. Another case of intraoperative subclinical arterial spasm at the place of microvascular anastomosis was revealed by dynamic ICG-videography. This flap did not develop postoperative complications. In conclusion, evaluation of perfusion by ICG imaging is feasible in all kinds of microsurgical flaps, irrespective of the type of tissue. Even though not meeting all the criteria of an ideal monitoring device, significant additional information can be obtained. In this study, cases with arterial spasm, venous congestion, and regional hypoperfusion were revealed by intraoperative ICG-videography. There was a strong correlation between intraoperative findings and clinical outcome.

Intraoperative evaluation of skin-flap viability using laser-induced fluorescence of indocyanine green

Laser-induced fluorescence of indocyanine green (ICG) is a new method for evaluating skin perfusion, which is superior to conventional fluorescein angiography. In a prospective clinical study ICG fluorescence video-angiography was used for the intraoperative evaluation of skin-flap perfusion. The results of ICG imaging were compared with clinical outcome 1 week postoperatively. Intraoperative ICG filling defects were always associated with delayed wound healing. In 50% of the patients, the regions of sloughing and epitheliolysis corresponded accurately to the regions of dye-filling deficits. All of the flaps without ICG filling defects healed primarily. These results suggest that ICG fluorescence is a sensitive tool for assessing nutritive blood flow in pedicled skin flaps with and without an axial vessel. Future clinical studies are required to establish critical threshold fluorescence indices that correlate with skin viability in the postoperative course.

Fatty acid specificity of hormone-sensitive lipase. Implication in the selective hydrolysis of triacylglycerols

The selective mobilization of fatty acids from white fat cells depends on their molecular structure, in particular the degree of unsaturation. The present study was designed to examine if the release of fatty acids by hormone-sensitive lipase (HSL) in vitro i) is influenced by the amount of unsaturation, ii) depends on the temperature, and iii) could explain the selective pattern of fatty acid mobilization and notably the preferential mobilization of certain highly unsaturated fatty acids. Recombinant rat and human HSL were incubated with a lipid emulsion. The hydrolysis of 35 individual fatty acids, ranging in chain length from 12 to 24 carbon atoms and in unsaturation from 0 to 6 double bonds was measured. Fatty acid composition of in vitro released NEFA was compared with that of fat cell triacylglycerols (TAG), the ratio % NEFA/% TAG being defined as the relative hydrolysis. The relative hydrolysis of individual fatty acids differed widely, ranging from 0.44 (24:1n-9) to 1.49 (18:1n-7) with rat HSL, and from 0.38 (24:1n-9) to 1.67 (18:1n-7) with human HSL. No major difference was observed between rat and human HSL. The relative release was dependent on the number of double bonds according to chain length. The amount of fatty acid released by recombinant rat HSL was decreased but remained robust at 4 degrees C compared with 37 degrees C, and the relative hydrolysis of some individual fatty acids was affected. The relative hydrolysis of fatty acids moderately, weakly, and highly mobilized by adipose tissue in vivo was similar and close to unity in vitro. We conclude that i) the release of fatty acids by HSL is only slightly affected by their degree of unsaturation, ii) the ability of HSL to efficiently and selectively release fatty acids at low temperature could reflect a cold adaptability for poikilotherms or hibernators when endogenous lipids are needed, and iii) the selectivity of fatty acid hydrolysis by HSL does not fully account for the selective pattern of fatty acid mobilization, but could contribute to explain the preferential mobilization of some highly unsaturated fatty acids compared with others.

The effect of exercise training on hormone-sensitive lipase in rat intra-abdominal adipose tissue and muscle

1. Adrenaline-stimulated lipolysis in adipose tissue may increase with training. The rate-limiting step in adipose tissue lipolysis is catalysed by the enzyme hormone-sensitive lipase (HSL). We studied the effect of exercise training on the activity of the total and the activated form of HSL, referred to as HSL (DG) and HSL (TG), respectively, and on the concentration of HSL protein in retroperitoneal (RE) and mesenteric (ME) adipose tissue, and in the extensor digitorum longus (EDL) and soleus muscles in rats. 2. Rats (weighing 96 +/- 1 g, mean +/- S.E.M.) were either swim trained (T, 18 weeks, n = 12) or sedentary (S, n = 12). Then RE and ME adipose tissue and the EDL and soleus muscles were incubated for 20 min with 4.4 microM adrenaline. 3. HSL enzyme activities in adipose tissue were higher in T compared with S rats. Furthermore, in RE adipose tissue, training also doubled HSL protein concentration (P < 0.05). In ME adipose tissue, the HSL protein levels did not differ significantly between T and S rats. In muscle, HSL (TG) activity as well as HSL (TG)/HSL (DG) were lower in T rats, whereas HSL (DG) activity did not differ between groups. Furthermore, HSL protein concentration in muscle did not differ between T and S rats (P > 0.05). 4. In conclusion, training increased the amount of HSL and the sensitivity of HSL to stimulation by adrenaline in intra-abdominal adipose tissue, the extent of the change differing between anatomical locations. In contrast, in skeletal muscle the amount of HSL was unchanged and its sensitivity to stimulation by adrenaline reduced after training.

[Ultrasonographic scanning of patients with severe abdominal injuries]

INTRODUCTION

The aim of this study was to describe our experiences with ultrasonography (US) of severely traumatised patients, and to show whether it is a safe and fast procedure when screening for intra-abdominal lesions.

MATERIAL AND METHODS

In a period from 1996 to 1999, 876 patients were received by the trauma team. The number of patients with an injury severity score (ISS) > 15, was constant during the period. Seventy-five per cent of the patients were men. One hundred and fifty-five patients (18%) died, 111 before US was carried out.

RESULTS

Over the four-year period, the number of patients received by the trauma team increased from 150 in 1996 to 365 in 1999. The number of US examinations increased from 61 (1996) till 303 (1999). The number of pathological US scans was constantly about 20 per year, where as the number of pathological CT scans was between ten and 20 per year. The number of patients that went on to explorative laparotomy was between seven and 17 per year and 49 in the whole period. The sensitivity of US to detect abdominal lesions is 0.74 and the specificity 0.97, whereas that to detect free abdominal fluid is 0.88 and the specificity 0.99.

DISCUSSION

US of the abdomen is a fast and safe procedure to carry out on the severely traumatised patient. An algorithm for diagnosis is suggested.