Open hip reduction using a novel transarticular suture stabilisation technique in 24 dogs: a retrospective study of technique, outcome and complications.

CASE HISTORY: Medical records of a single private practice (Illinois, USA) were retrospectively reviewed to identify dogs (n = 24) that had an open hip reduction with a transarticular suture stabilisation technique after presenting with a traumatic coxofemoral luxation between April 2003 and December 2018. CLINICAL FINDINGS: Dogs that met the inclusion criteria were of various breeds with a median body weight of 18.1 (min 4.2, max 54.5) kg and mean age at presentation of 6.5 (min 1, max 11) years. The surgical technique, short-term outcome and complications were extracted from the medical records. Long-term (>2 years) follow-up data was obtained by a telephone interview with each owner. TREATMENT AND OUTCOME: All dogs underwent open hip reduction using a novel transarticular suture stabilisation technique. The outcome was reported by owners to be excellent in 18/24 (75%) dogs with full return of limb function. Sixty-six percent (16/24) of owners reported that no lameness was observed 2 months after surgery. No minor complications were noted in this study. The hips of 6/24 (25%) dogs reluxated after surgery (defined as a major complication), which required femoral head and neck excision surgery. CLINICAL RELEVANCE: Open coxofemoral joint reduction using a novel transarticular suture technique is a viable surgical option to consider in dogs that present with a traumatic coxofemoral luxation.

Functional host-specific adaptation of the intestinal microbiome in hominids.

Fine-scale knowledge of the changes in composition and function of the human gut microbiome compared that of our closest relatives is critical for understanding the evolutionary processes underlying its developmental trajectory. To infer taxonomic and functional changes in the gut microbiome across hominids at different timescales, we perform high-resolution metagenomic-based analyzes of the fecal microbiome from over two hundred samples including diverse human populations, as well as wild-living chimpanzees, bonobos, and gorillas. We find human-associated taxa depleted within non-human apes and patterns of host-specific gut microbiota, suggesting the widespread acquisition of novel microbial clades along the evolutionary divergence of hosts. In contrast, we reveal multiple lines of evidence for a pervasive loss of diversity in human populations in correlation with a high Human Development Index, including evolutionarily conserved clades. Similarly, patterns of co-phylogeny between microbes and hosts are found to be disrupted in humans. Together with identifying individual microbial taxa and functional adaptations that correlate to host phylogeny, these findings offer insights into specific candidates playing a role in the diverging trajectories of the gut microbiome of hominids. We find that repeated horizontal gene transfer and gene loss, as well as the adaptation to transient microaerobic conditions appear to have played a role in the evolution of the human gut microbiome.

Optimising aerial military medical evacuation dispatching decisions via operations research techniques.

Senior military leaders and medical practitioners continuously seek new ways to improve the performance and organisation of deployed medical evacuation (MEDEVAC) systems to minimise mortality rates of combat casualties. The objective of this paper is to highlight how recent research in the fields of operations research and machine learning can be leveraged to better inform the implementation and modification of current and future MEDEVAC tactics, techniques and procedures for combat operations in a deployed environment. More specifically, this paper discusses state-of-the-art techniques that optimise the management of MEDEVAC assets prior to and during combat operations. These recent research efforts emphasise that military healthcare administrators should contribute to and extend the evolving portfolio of research that seeks to design and develop decision support systems leveraging artificial intelligence and operations research to improve MEDEVAC system performance.

Relation between dairy food intake and cognitive function: The Maine-Syracuse Longitudinal Study.

Diet modification to alter the course of age-related cognitive decline is becoming increasingly important. Few observational findings suggest that dairy food intake may be positively related to cognitive function, but research in this novel area is limited. The aim of this study was to investigate whether dairy food intake is associated with cognitive function, before and after adjustment for cardiovascular, lifestyle and dietary factors. To do this, a cross-sectional analyses of a subset of the community-based Maine-Syracuse Longitudinal Study (MSLS) sample (N = 972) was undertaken. It was determined that participants who consumed dairy products at least once per day had significantly higher scores on multiple domains of cognitive function compared with those who never or rarely consumed dairy foods, adjusting for cardiovascular risk factors, lifestyle and dietary factors. Frequent dairy food intake is associated with better cognitive performance but underlying causal mechanisms are still to be determined.

Coronary artery disease in a large renal transplant population: implications for management.

Coronary artery disease (CAD) accounts for approximately one-half of the sizable mortality in patients with end-stage renal disease who have undergone transplantation. The study was a retrospective review of 1460 patients who underwent renal transplantation at the Mount Sinai Medical Center from January 1, 2000 to October 31, 2009. Noninvasive stress testing was performed in 848 patients (88.1%) with 278 patients (32.8%) having abnormal results. Cardiac catheterization was performed in 357 patients (37.1%) and of these, 212 patients had obstructive disease (59.4%). At 5 years posttransplant, there was no statistically significant difference between those with nonobstructive CAD and those who required percutaneous or surgical interventions (adjusted hazard ratio [aHR], 1.243; CI 95%, 0.513-3.010; p = 0.630). Those with medically managed obstructive CAD had significantly higher rates of death at the 5-year period when compared to those who received percutaneous intervention (aHR, 3.792; CI 95%, 1.320-10.895; p = 0.013) or those who received coronary artery bypass grafting (aHR, 6.691; CI 95%, 1.200-37.323). Because noninvasive imaging is poorly predictive of coronary disease in this high-risk population, an anatomic diagnosis is recommended. Revascularization may result in improved long-term outcomes.

Population structure and genetic differentiation associated with breeding history and selection in tomato (Solanum lycopersicum L.).

Tomato (Solanum lycopersicum L.) has undergone intensive selection during and following domestication. We investigated population structure and genetic differentiation within a collection of 70 tomato lines representing contemporary (processing and fresh-market) varieties, vintage varieties and landraces. The model-based Bayesian clustering software, STRUCTURE, was used to detect subpopulations. Six independent analyses were conducted using all marker data (173 markers) and five subsets of markers based on marker type (single-nucleotide polymorphisms, simple sequence repeats and insertion/deletions) and location (exon and intron sequences) within genes. All of these analyses consistently separated four groups predefined by market niche and age into distinct subpopulations. Furthermore, we detected at least two subpopulations within the processing varieties. These subpopulations correspond to historical patterns of breeding conducted for specific production environments. We found no subpopulation within fresh-market varieties, vintage varieties and landraces when using all marker data. High levels of admixture were shown in several varieties representing a transition in the demarcation between processing and fresh-market breeding. The genetic clustering detected by using the STRUCTURE software was confirmed by two statistics, pairwise F(st) (θ) and Nei's standard genetic distance. We also identified a total of 19 loci under positive selection between processing, fresh-market and vintage germplasm by using an F(st)-outlier method based on the deviation from the expected distribution of F(st) and heterozygosity. The markers and genome locations we identified are consistent with known patterns of selection and linkage to traits that differentiate the market classes. These results demonstrate how human selection through breeding has shaped genetic variation within cultivated tomato.

Assembly and regulation of the CD40 receptor complex in human B cells.

CD40 is a member of the tumor necrosis factor (TNF) receptor superfamily. Studies with human B cells show that the binding of CD154 (gp39, CD40L) to CD40 recruits TNF receptor- associated factor 2 (TRAF2) and TRAF3 to the receptor complex, induces the downregulation of the nonreceptor-associated TRAFs in the cell and induces an increased expression of Fas on the cell surface. Combined signaling through the interluekin 4 receptor and CD40 induces an increased expression of Fas with a commensurate increase in the level of TRAF2, but not TRAF3, that is recruited to the receptor complex. In contrast, engagement of the membrane immunoglobulin and CD40 limits Fas upregulation and reduces the recruitment of TRAF2, relative to TRAF3, to the CD40 receptor complex. These studies show that the TRAF composition of the CD40 receptor complex can be altered by signals that influence B cell differentiation.

Microbial fingerprinting using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) applications and challenges.

Recent threats posed by pathogenic microorganisms in food, recreational waters, and as agents of bioterror have underscored the need for the development of more rapid, accurate, and cost-effective methods of microbial characterization and identification. This chapter focuses on the use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to rapidly characterize and identify microorganisms through generation of characteristic fingerprints of intact cells. While most efforts have focused on bacteria, this technology has also been applied to fungi and viruses. Results of most studies suggest that MALDI-TOF MS can be used to rapidly and accurately characterize microorganisms. A variety of quantitative approaches have been employed in the analysis of MALDI-TOF MS fingerprints of microorganisms. The reproducibility of fingerprints of intact cells remains a primary concern and limitation associated with this approach. Protocols and instrumentation used have varied considerably and likely account for much of the variability in reproducibility reported. Key first steps to overcoming this limitation will be the development of standard approaches to quantifying reproducibility and the development of standard protocols for sample preparation and analysis.

MR Myelography for the Detection of CSF-Venous Fistulas.

CSF-venous fistula is an important treatable cause of spontaneous intracranial hypotension that is often difficult to detect using traditional imaging techniques. Herein, we describe the technical aspects and diagnostic performance of MR myelography when used for identifying CSF-venous fistulas. We report 3 cases in which the CSF-venous fistula was occult on CT myelography but readily detected using MR myelography.

Presence of the APOE epsilon4 allele modifies the relationship between type 2 diabetes and cognitive performance: the Maine-Syracuse Study.

AIMS/HYPOTHESIS: The primary aim of this study was to determine whether the presence of one or more APOE epsilon4 alleles modifies the association between diabetes (defined by glucose > or =7 mmol/l or treatment) and cognitive function. METHODS: Diabetic status and APOE genotype interactions were assessed cross-sectionally for 826 community-dwelling, stroke-free, non-demented individuals (526 non-diabetic non-APOE epsilon4 carriers, 174 non-diabetic APOE epsilon4 carriers, 87 diabetic APOE epsilon4 non-carriers, 39 diabetic APOE epsilon4 carriers) ranging in age from 50 to 98 years. Cognitive function was assessed using the Mini-Mental State Examination (MMSE), the similarities subtest from the Wechsler Adult Intelligence Scale, and four composite scores derived from 17 additional neuropsychological tests. Multiple linear regression analyses were employed to relate diabetes and APOE genotype to cognitive performance and to examine the interaction between these two risk factors as they relate to cognitive performance. Multiple cardiovascular disease risk factors were statistically controlled. RESULTS: With adjustment for age, education, sex, race/ethnicity and APOE genotype, performance level was lower for the diabetic than for the non-diabetic group for the MMSE, the similarities subtest and each of the cognitive composites with the exception of the verbal memory composite. Interactions (p < 0.05) between diabetes and APOE genotype were found for all but the visual-spatial memory/organisation composite. The negative association between diabetes and cognitive performance was of a higher magnitude for individuals who carry one or more APOE epsilon4 alleles. Results were similar with additional adjustment for cardiovascular disease and associated risk factors. CONCLUSIONS/INTERPRETATION: The presence of one or more APOE epsilon4 alleles modifies the association between diabetes and cognitive function.

Molecular origins of friction: the force on adsorbed layers.

Simulations and perturbation theory are used to study the molecular origins of friction in an ideal model system, a layer of adsorbed molecules sliding over a substrate. These calculations reproduce several surprising features of experimental results. In most cases, the frictional force on a solid monolayer has a different form from that observed between macroscopic solids. No threshold force or static friction is needed to initiate sliding; instead, the velocity is proportional to the force. As in experiments, incommensurate solid layers actually slide more readily than fluid layers. A comparison of experiment, simulation, and analytic results shows that dissipation arises from anharmonic coupling between phonon modes and substrate-induced deformations in the adsorbate.

Origin of stick-slip motion in boundary lubrication.

Molecular dynamics simulations of atomically thin, fluid films confined between two solid plates are described. For a broad range of parameters, a generic stick-slip motion is observed, consistent with the results of recent boundary lubrication experiments. Static plates induce crystalline order in the film. Stick-slip motion involves periodic shear-melting transitions and recrystllization of the film. Uniform motion occurs at high velocities where the film no longer has time to order. These results indicate that the origin of stick-slip motion is thermodynamic instability of the sliding state, rather than a dynamic instability as usually assumed.

Status of women microbiologists.

The general picture that emerges from this study is that the woman microbiologist, upon entering the professional job market, faces (i) slower advancement; (ii) restricted extramural recognition; and (iii) fewer positions of a supervisory or administrative nature, when compared to men. Most striking is the salary differential, which increases with increasing educational level, with increasing rank, and with increasing seniority. From the beginning of her professional training, the woman microbiologist feels handicapped by lack of encouragement and proper role models. She generally receives little advice regarding her professional future and rarely feels pushed to take the most challenging position. Should she be married, she feels that her mobility is severely restricted. Even though the subjective nature of these feelings may be interpreted as projections of failure, subtle inducements for women to stay at lower levels may well exist, in addition to more objective measurements, such as lower salary levels and slower professional advancement. Despite these handicaps, professional women continue to work. As a group, they work for the same reasons that men do, they work as long and as hard as men do, and they remain at their positions as long as men do. Women and men rate themselves equally as to job performance, degree of independence, and publication rate. On the basis of this study, it should not be surprising that women professionals are less visible than men and that only a small proportion of women become what is considered successful by the usual external criteria. If women were to receive continued encouragement, scientific contact, and professional recognition at each stage of their professional lives, they would undoubtedly become more visible. The lack of encouragement and selfconfidence leading to isolation, which then leads to lack of recognition, is a vicious circle that must be broken for the woman professional. This can be done most easily for the beginning student. For older women, there must be increased placement in positions of responsibility and visibility. Protective practices that discourage women from entering arenas of competition can only be viewed as discrimination on the basis of sex, since women professionals are rarely given the choice between being protected and being independent. Unexpectedly, this study illustrates the lower status of another group of individuals who are considered deviants from the expected roles of the established society-single men with doctorates, who were found in the positions predominately filled by women. In conclusion, this study of a select group of scientists probably has general applicability to all women professionals in their roles vis-à-vis men. Examination and documentation of discriminatory practices based on sex points to the areas in which women must direct their demands for equality.

Evaluation of four hematology and a chemistry portable benchtop analyzers using non-human primate blood.

BACKGROUND: Near patient testing (NPT) and point-of-care testing (POCT) using portable benchtop analyzers has become necessary in many areas of the medical community, including biocontainment. METHODS: We evaluated the Beckman AcT diff, Abaxis Vetscan HMII (two instruments), Abbott Cell-Dyn 1800, and Abaxis Vetscan VS2 for within-run precision and correlation to central laboratory instruments using non-human primates blood. RESULTS: Compared with the central laboratory instruments, the Beckman AcT diff correlated on 80%; the HMII instruments on 31% and 44%, the CD1800 on 31%, and the VS2 on 71% of assays. For assays with published manufacturers precision guidelines, the AcT diff met all nine, the HMII instruments met one and six of six, and the CD 1800 met one of six. CONCLUSIONS: Laboratories using NPT/POCT must test their individual instruments for precision and correlation, identify assays that are reliable, and exclude or develop supplemental procedures for assays that are not.

Modelling approaches to the dewetting of evaporating thin films of nanoparticle suspensions.

We review recent experiments on dewetting thin films of evaporating colloidal nanoparticle suspensions (nanofluids) and discuss several theoretical approaches to describe the ongoing processes including coupled transport and phase changes. These approaches range from microscopic discrete stochastic theories to mesoscopic continuous deterministic descriptions. In particular, we describe (i) a microscopic kinetic Monte Carlo model, (ii) a dynamical density functional theory and (iii) a hydrodynamic thin film model. Models (i) and (ii) are employed to discuss the formation of polygonal networks, spinodal and branched structures resulting from the dewetting of an ultrathin 'postcursor film' that remains behind a mesoscopic dewetting front. We highlight, in particular, the presence of a transverse instability in the evaporative dewetting front, which results in highly branched fingering structures. The subtle interplay of decomposition in the film and contact line motion is discussed. Finally, we discuss a simple thin film model (iii) of the hydrodynamics on the mesoscale. We employ coupled evolution equations for the film thickness profile and mean particle concentration. The model is used to discuss the self-pinning and depinning of a contact line related to the 'coffee-stain' effect. In the course of the review we discuss the advantages and limitations of the different theories, as well as possible future developments and extensions.

Looking for the "connection": A clinical vignette on pediatric chest wall masses.

Chest wall masses in the pediatric population are relatively rare, and the differential diagnosis predominantly includes neoplastic soft tissue or osseous tumours, either benign or malignant in etiology, although local infectious processes represent additional diagnostic possibilities. Among recent immigrants, a more diverse array of less commonly observed pathogens warrant consideration. Here, we present a case of a chest wall mass in an immunocompetent child who had recently immigrated from the Philippines.

Les masses de la paroi thoracique sont relativement rares dans la population pédiatrique, et le diagnostic différentiel touche surtout les tumeurs néoplasiques des tissus mous ou des os, d'étiologie bénigne ou maligne, même si les processus infectieux locaux s'ajoutent aux possibilités diagnostiques. Chez des immigrants récents, de nombreux agents pathogènes moins fréquents méritent d'être envisagés. Les chercheurs présentent un cas de masse de la paroi thoracique chez un enfant immunocompétent récemment immigré des Philippines.

Involvement of homologous recombination repair after proton-induced DNA damage.

Protection from chronic exposure to cosmic radiation, which is primarily composed of protons, in future manned missions to Mars and beyond is considered to be a key unresolved issue. To model the effects of cosmic radiation on a living cell, we used Saccharomyces cerevisiae cells harboring various deletions of DNA repair genes to investigate the response of cells to DNA strand breaks caused by exposure to 250 MeV proton irradiation (linear energy transfer of 0.41 keV/microm). In our study, DNA strand breaks induced by exposure to protons were predominantly repaired via the homologous recombination and postreplication repair pathways. We simulated chronic exposure to proton irradiation by treating cells from colonies that survived proton treatment, after several rounds of subculturing, to a second proton dose, as well as additional cell stressors. In general, cells cultured from proton surviving colonies were not more sensitive to secondary cell stressors. However, cells from rad52delta colonies that survived proton treatment showed increased resistance to secondary stressors, such as gamma-rays (1.17 and 1.33 MeV; 0.267 keV/microm), ultraviolet (UV) and proton irradiation and elevated temperatures. Resistance to secondary stressors was also observed in rad52delta cells that survived exposure to gamma-rays, rather than protons, but this was not observed to occur in rad52delta cells after UV irradiation. rad52delta cells that survived exposure to protons, followed by gamma-rays (proton surviving colonies were cultured prior to gamma-ray exposure), exhibited an additive effect, whereby these cells had a further increase in stress resistance. A genetic analysis indicated that increased stress resistance is most likely due to a second-site mutation that suppresses the rad52delta phenotype. We will discuss possible origins of these second-site mutations.

Differential expression of IEG mRNA in rat brain following acute treatment with clozapine or haloperidol: a semi-quantitative RT-PCR study.

Antipsychotic drugs have been shown to modulate immediate early gene (IEG) expression in rat brain regions that are associated with schizophrenia, which may be directly linked to their immediate therapeutic benefit. In this study, we analysed the expression profile of a series of IEGs (c-fos, c-jun, fra-1, Krox-20, Krox-24, arc, sgk-1, BDNF and NARP) in six rat brain regions (prefrontal cortex, hippocampus, striatum, nucleus accumbens, thalamus and cerebellum). Rats (n=5) were administered either clozapine (20 mg/kg i.p.), haloperidol (1 mg/kg i.p.) or the appropriate vehicle with pre-treatment times of 1, 6 and 24 h. IEG expression was analysed in these regions by Taqman RT-PCR. The spatial and temporal profile of IEG induction following antipsychotic drug treatment correlates with regions associated with the efficacy and side effect profile of each drug. In particular, sgk-1 expression levels after antipsychotic drug treatment may have predictive value when investigating the profile of a novel antipsychotic drug.

Chronic psychological stress enhances nociceptive processing in the urinary bladder in high-anxiety rats.

This study sought to determine whether acute and/or chronic psychological stress produce changes in urinary bladder nociception. Female Sprague-Dawley (SD; low/moderate anxiety) or Wistar-Kyoto (WK; high-anxiety) rats were exposed to either an acute (1 day) or a chronic (10 days) water avoidance stress paradigm or a sham stress paradigm. Paw withdrawal thresholds to mechanical and thermal stimuli and fecal pellet output, were quantified at baseline and after the final stress or sham stress exposure. Rats were then sedated, and visceromotor responses (VMRs) to urinary bladder distension (UBD) were recorded. While acute stress exposure did not significantly alter bladder nociceptive responses in either strain of rats, WK rats exposed to a chronic stress paradigm exhibited enhanced responses to UBD. These high-anxiety rats also exhibited somatic analgesia following acute, but not chronic, stress. Furthermore, WK rats had greater fecal pellet output than SD rats when stressed. Significant stress-induced changes in nociceptive responses to mechanical stimuli were observed in SD rats. That chronic psychological stress significantly enhanced bladder nociceptive responses only in high-anxiety rats provides further support for a critical role of genetics, stress and anxiety as exacerbating factors in painful urogenital disorders such as interstitial cystitis (IC).