Psychological factors not strength deficits are associated with severity of gluteal tendinopathy: A cross-sectional study.

BACKGROUND: Gluteal tendinopathy is the most common lower limb tendinopathy presenting to general practice. It has a high prevalence amongst middle-aged women and impacts on daily activities, work participation and quality of life. The aim was to compare physical and psychological characteristics between subgroups of severity of pain and disability. METHODS: A multicentre cross-sectional cohort of 204 participants (mean age 55 years, 82% female) who had a clinical diagnosis of gluteal tendinopathy with magnetic resonance imaging confirmation were assessed. A range of physical and psychosocial characteristics were recorded. Pain and disability were measured with the VISA-G questionnaire. A cluster analysis was used to identify mild, moderate and severe subgroups based on total VISA-G scores. Between-group differences were then evaluated with a MANCOVA, including sex and study site as covariates, followed by a Bonferroni post hoc test. Significance was set at 0.05. RESULTS: There were significantly higher pain catastrophizing and depression scores in the more severe subgroups. Lower pain self-efficacy scores were found in the severe group compared to the moderate and mild groups. Greater waist girth and body mass index (BMI), lower activity levels and poorer quality of life were reported in the severe group compared to the mild group. Hip abductor muscle strength and hip circumference did not differ between subgroups of severity. CONCLUSIONS: Individuals with severe gluteal tendinopathy present with psychological distress, poorer quality of life, greater BMI and waist girth. Given these features, the consideration of psychological factors in more severe patients may be important to optimize patient outcomes and reduce healthcare utilization. SIGNIFICANCE: Patients with severe gluteal tendinopathy exhibit greater psychological distress, poorer quality of life and greater waist girth and BMI when compared to less severe cases. This implies that clinicians ought to consider psychological factors in the management of more severe gluteal tendinopathy.

Achilles and patellar tendinopathy display opposite changes in elastic properties: A shear wave elastography study.

To compare tendon elastic and structural properties of healthy individuals with those with Achilles or patellar tendinopathy. Sixty-seven participants (22 Achilles tendinopathy, 17 patellar tendinopathy, and 28 healthy controls) were recruited between March 2015 and March 2016. Shear wave velocity (SWV), an index of tissue elastic modulus, and tendon thickness were measured bilaterally at mid-tendon and insertional regions of Achilles and patellar tendons by an examiner blinded to group. Analysis of covariance, adjusted for age, body mass index, and sex was used to compare differences in tendon thickness and SWV between the two tendinopathy groups (relative to controls) and regions. Tendon thickness was included as a covariate for analysis of SWV. Compared to controls, participants with Achilles tendinopathy had lower SWV at the distal insertion (Mean difference MD; 95% CI: -1.56; -2.49 to -0.62 m/s; P < .001) and greater thickness at the mid-tendon (MD 0.19; 0.05-0.33 cm; P = .007). Compared to controls, participants with patellar tendinopathy had higher SWV at both regions (MD 1.25; 0.40-2.10 m/s; P = .005) and greater thickness proximally (MD 0.17; 0.06-0.29 cm; P = .003). Compared to controls, participants with Achilles and patellar tendinopathy displayed lower Achilles tendon elastic modulus and higher patellar tendon elastic modulus, respectively. More research is needed to explore whether maturation, aging, or chronic load underlie these findings and whether current management programs for Achilles and patellar tendinopathy need to be tailored to the tendon.

Comparison of corticosteroid, autologous blood or sclerosant injections for chronic tennis elbow.

OBJECTIVES: To compare three different ultrasound-guided injections for chronic tennis elbow. DESIGN: Assessor-blinded, randomized controlled comparative trial. METHODS: 44 patients with clinically diagnosed tennis elbow, confirmed by Doppler ultrasound, received under ultrasound guidance, a single corticosteroid injection (n=14), or two injections (separated by 4 weeks) of either autologous blood (n=14) or polidocanol (n=16). Clinical and ultrasound examination was performed at baseline, 4, 12 and 26 weeks. RESULTS: Complete recovery or much improvement was greater for corticosteroid injection than autologous blood and polidocanol at 4 weeks (p<0.001, number needed to treat 1 (95% CI 1-2)). In contrast, at 26 weeks corticosteroid was significantly worse than polidocanol (p=0.004, number needed to harm 2 (1-6)). Recurrence after corticosteroid injection was significantly higher than autologous blood or polidocanol (p=0.007, number needed to harm 2 (1-4)). Corticosteroid injection produced greater reduction in tendon thickness and vascularity than autologous blood at 4 weeks only. Compared to autologous blood, polidocanol reduced tendon thickness at 4 and 12 weeks and reduced echogenicity and hyperaemia after 12 or 26 weeks respectively. CONCLUSIONS: Injections of corticosteroid cannot be recommended over polidocanol or autologous blood, because despite beneficial short-term effect there were inferior long-term effects. Whether polidocanol or autologous blood injections are effective is unknown, especially as their global effect profiles are not unlike previously reported for wait-and-see.

IL-10 produced by trophoblast cells inhibits phagosome maturation leading to profound intracellular proliferation of Salmonella enterica Typhimurium.

INTRODUCTION: Salmonella enterica Typhimurium (ST) is a phagosomal pathogen that can infect placental trophoblast cells leading to abortion and severe maternal illness. It is unclear how the trophoblast cells promote profound bacterial proliferation. METHODS: The mechanism of internalization, intracellular growth and phagosomal biogenesis in ST-infected human epithelial (HeLa), macrophage (THP-1) and trophoblast-derived cell lines (JEG-3, BeWo and HTR-8) was studied. Specific inhibitors were used to block bacterial internalization. Phagosomal maturation was determined by confocal microscopy, Western-blotting and release of lysosomal ß-galactosidase by infected cells. Bacterial colony forming units were determined by plating infected cell lysates on agar plates. RESULTS: ST proliferated minimally in macrophages but replicated profoundly within trophoblast cells. The ST-ΔinvA (a mutant of Salmonella pathogenicity island-1 gene effector proteins) was unable to infect epithelial cells, but was internalized by scavenger receptors on trophoblasts and macrophages. However, ST was contrastingly localized in early (Rab5⁺) or late (LAMP1⁺) phagosomes within trophoblast cells and macrophages respectively. Furthermore trophoblast cells (unlike macrophages) did not exhibit phagoso-lysosomal fusion. ST-infected macrophages produced IL-6 whereas trophoblast cells produced IL-10. Neutralizing IL-10 in JEG-3 cells accelerated phagolysomal fusion and reduced proliferation of ST. Placental bacterial burden was curtailed in vivo in anti-IL-10 antibody treated and IL-10-deficient mice. DISCUSSION: Macrophages phagocytose but curtail intracellular replication of ST in late phagosomes. In contrast, phagocytosis by trophoblast cells results in an inappropriate cytokine response and proliferation of ST in early phagosomes. CONCLUSION: IL-10 production by trophoblast cells that delays phagosomal maturation may facilitate proliferation of pathogens in placental cells.

A new integrative model of lateral epicondylalgia.

Tennis elbow or lateral epicondylalgia is a diagnosis familiar to many within the general community and presents with an uncomplicated clinical picture in most cases. However, the underlying pathophysiology presents a more complex state and its management has not been conclusively determined. Research on this topic extends across anatomical, biomechanical and clinical literature; however, integration of findings is lacking. We propose that the current understanding of the underlying pathophysiology of lateral epicondylalgia can be conceptualised as encompassing three interrelated components: (i) the local tendon pathology, (ii) changes in the pain system, and (iii) motor system impairments. This paper presents a model that integrates these components on the basis of a literature review with the express aim of assisting in the targeting of specific treatments or combinations thereof to individual patients.

Strategic targeting of essential host-pathogen interactions in chlamydial disease.

The chlamydiae are obligate intracellular gram-negative bacteria that are exquisitely adapted for exploitation of their hosts and contribute to a wide range of acute and chronic human diseases. Acute infections treated with non-cidal antibiotics can lead to the development of persistent, non-replicating bacteria with the corollary that these persistent (yet viable) chlamydiae can resist eradication by further antimicrobial treatment and cause chronic disease. These findings highlight an urgent need for therapeutics that are effective against persistent infections and call for creative approaches to identify potential drug targets. The C. pneumoniae and C. trachomatis genome projects have greatly expanded our knowledge of chlamydial pathogenesis and have provided an enormous potential for the identification and characterization of unknown genes and potential virulence factors in these bacteria. As intracellular pathogens, chlamydiae rely on host cells for all aspects of their survival, from the initial attachment with host cell membranes, to cellular invasion, acquisition of host cell metabolites and intracellular replication. As such, the molecules participating in interactions with the host could be attractive targets for therapeutic intervention. This review describes recent advances in chlamydial genomics, proteomics and cell biology that have cast light on host-pathogen relations that are essential for chlamydial survival. Using this knowledge, we discuss how strategically interfering with essential interactions between chlamydiae and the host cell could be exploited to develop an innovative, and potentially more relevant arsenal of therapeutic compounds.

Dendritic cell discoveries provide new insight into the cellular immunobiology of DNA vaccines.

The evolution of increasingly virulent human pathogens, together with the rapid onset of antimicrobial resistance has created a need for new vaccination strategies. Nucleic acid vaccines, based on recombinant DNA technology are a promising new vaccine formulation capable of eliciting both humoral and cellular immune responses. This technology has been experimentally validated in animal models of pathogen challenge and tumor protection following administration of a DNA vaccine and has led to extensive research into the mechanisms of protective immunity. We focus here on the cellular and molecular mechanisms leading to cell-mediated immune responses to DNA vaccines and discuss these mechanisms in light of recent advances in the field of dendritic cell immunobiology. In particular, the potential involvement of: (i) the CpG pattern-recognition receptor, toll-like receptor-9; (ii) the dendritic cell-specific surface adhesion molecule, DC-SIGN; and (iii) the molecular interactions between CD40 and CD154 in the evolution of protective cell-mediated immunity to DNA vaccines are discussed. An improved understanding of the precise mechanisms leading to protective cellular immunity following DNA vaccination may help in the design of novel DNA constructs containing immunostimulatory features that target one or more of these mechanisms, with the aim of increasing the immunogenic potential and protective efficacy of DNA vaccines.

Chlamydia pneumoniae and atherosclerosis: does the evidence support a causal or contributory role?

The intracellular bacterial pathogen Chlamydia pneumoniae causes respiratory tract infection and has been associated with atherosclerosis and coronary artery disease. Since atherosclerosis is a progressive disease and is considered to be a chronic inflammation of the artery vessel wall, the interaction of C. pneumoniae with cells of the vasculature that can result in a local inflammatory response is of paramount importance. In this essay we review the pathophysiology of atherosclerosis in the context of C. pneumoniae infection and present an integrated model that includes the involvement of C. pneumoniae in all stages of atherogenesis including initiation, inflammation, fibrous plaque formation, plaque rupture and thrombosis. We hypothesize that acute and persistent infection of professional immune cells (T-cells, monocytes and macrophages) and non-immune cells (endothelial cells and smooth muscle cells) contributes to a sustained inflammatory response mediated by extensive cellular 'crosstalk' and numerous cytokines/chemokines. This cascade of inflammatory mediators may contribute to cellular dysfunction and tissue remodelling of the arterial intima. An improved understanding of the precise mechanism(s) of C. pneumoniae involvement in atherogenesis may help resolve the question of causality however, at the present time, we interpret the data as favoring a contributory rather than a causal role. Future research directed at the discovery of chlamydial virulence factors necessary for intracellular survival and subsequent alterations in host cell gene expression including signalling pathways may be important for the design of future clinical trials.

cDNA array analysis of altered gene expression in human endothelial cells in response to Chlamydia pneumoniae infection.

Strong epidemiological and pathological evidence supports a role for Chlamydia pneumoniae infection in atherosclerosis and human coronary heart disease. Animal models have shown that C. pneumoniae disseminates hematogenously in infected monocytes and macrophages, while in vitro data suggest that infected macrophages can transmit C. pneumoniae infection directly to endothelial cells. Endothelial cells may be key in vivo targets for C. pneumoniae infection; given that these cells are important in regulating the dynamics of the vessel wall, we used cDNA microarrays to study the transcriptional response of endothelial cells to infection with C. pneumoniae. cDNA arrays were used to characterize the mRNA expression profiles for 268 human genes following infection with C. pneumoniae, which were compared to mRNA profiles of uninfected cells. Selected genes of interest were further investigated by reverse transcription-PCR throughout a 24-h period of infection. C. pneumoniae infection upregulated mRNA expression for approximately 20 (8%) of the genes studied. Genes coding for cytokines (interleukin-1), chemokines (monocyte chemotactic protein 1 and interleukin-8), and cellular growth factors (heparin-binding epidermal-like growth factor, basic fibroblast growth factor, and platelet-derived growth factor B chain) were the most prominently upregulated. In addition to these families of genes, increases in mRNA levels for intracellular kinases and cell surface receptors with signal transduction activities were observed. Time course experiments showed that mRNA levels were upregulated within 2 h following infection. These results expand our knowledge of the response of endothelial cells to C. pneumoniae by further defining the repertoire of C. pneumoniae-inducible genes and provide new insight into potential mechanisms of atherogenesis. In addition, the use of cDNA microarrays may prove useful for the study of host cell responses to C. pneumoniae infection during latent and replicative stages of infection and related pathology.

Quantitation of Chlamydia trachomatis 16S rRNA using NASBA amplification and a bioluminescent microtiter plate assay.

We developed a nucleic acid sequence based amplification (NASBA) assay which employs the recombinant photoprotein Aequorin in a microtiter plate format for detection and quantitation of C. trachomatis that may be useful in large scale epidemiological studies aimed at improving our understanding of factors affecting transmission of this sexually transmitted pathogen. The conditions for NASBA amplification of the16S rRNA target were optimized (90 mM KCl, 12 mM MgCl(2), 0.2 microM P1 and P2 primers), amplified RNA was captured by a biotin-labelled capture probe immobilized onto streptavidin coated microtiter plates and detected with an FITC-labelled oligonucleotide probe and Aequorin-anti-FITC antibody conjugate. The analytical sensitivity of NASBA was 1,000 in vitro generated RNA transcripts and 1.6 IFU of C. trachomatis. The sensitivity of NASBA using the bioluminescent assay was 10 fold higher than Northern blotting. Time course amplification experiments performed with 10 fold serial dilutions of target established that amplification was linear at 75 min and extended over a range of five log units of input RNA copy number. Linear regression analysis confirmed a linear fit for the data with r(2) = 0.959 (p < 0.004). A double log plot of RLU signal versus copy number was linear; analysis of residuals from a series of runs tests confirmed a fit with a linear model (number of runs = 3, p = 0.5 where p < 0.05 indicates statistical deviation from a linear model). NASBA amplification coupled with bioluminescent detection in a microtiter plate format should provide a useful tool for quantitation of C. trachomatis in clinical specimens for use in epidemiological studies.

Nucleic acid sequence based amplification (NASBA) of Chlamydia pneumoniae major outer membrane protein (ompA) mRNA with bioluminescent detection.

Chlamydia pneumoniae has been associated with chronic conditions such as atherosclerosis and coronary heart disease but the precise role of this intracellular bacteria in the pathogenesis of these diseases is not well defined. Several techniques have been developed for detection of C. pneumoniae in atheromatous lesions, however it remains unclear whether persistent forms of the organism and/or actively replicating bacteria contribute to associated pathology. The aim of this study was to utilize nucleic acid sequence based amplification (NASBA) technology together with a highly sensitive aequorin bioluminescent hybridization assay for the detection of C. pneumoniae ompA mRNA transcripts. A NASBA targeting the ompA gene of C. pneumoniae was developed, and the sensitivity was evaluated using both C. pneumoniae ompA RNA generated in vitro, and purified C. pneumoniae inclusion forming units (IFU). C. pneumoniae NASBA was capable of detecting between 100 and 1000 ompA RNA molecules and could detect 0.2 IFU of C. pneumoniae using the aequorin bioluminescent assay. The sensitivity of the bioluminescent assay was at least 10-fold higher than Northern blot detection. The linearity of NASBA amplification was assessed in time-course amplification experiments with different input numbers of RNA molecules. When NASBA products were analyzed during the linear phase of amplification, the dynamic range of bioluminescent detection extended over 8-log units of input RNA copy number. NASBA amplification coupled with bioluminescent detection may prove to be a useful molecular tool for the detection, quantitation and analysis of differentially expressed chlamydial genes during various stages of infection and disease pathology or for other mRNAs of interest in different disease processes.

Analytical sensitivity, reproducibility of results, and clinical performance of five PCR assays for detecting Chlamydia pneumoniae DNA in peripheral blood mononuclear cells.

Chlamydia pneumoniae has been associated with atherosclerosis and coronary artery disease (CAD), and its DNA has been detected in atheromatous lesions of the aorta, carotid, and coronary arteries by a variety of PCR assays. The objective of this study was to compare the performances of five published PCR assays in the detection of C. pneumoniae in peripheral blood mononuclear cells (PBMCs) from patients with coronary artery disease. The assays included two conventional PCRs, one targeting a cloned PstI fragment and one targeting the 16S rRNA gene; two nested PCRs, one targeting the 16S rRNA gene and one targeting ompA; and a touchdown enzyme time release (TETR) PCR, targeting the 16S rRNA gene. All PCRs had similar analytical sensitivities and detected a minimum of 0.005 inclusion-forming units (IFU) of C. pneumoniae; the ompA nested PCR and the TETR PCR were slightly more sensitive and detected 0.001 IFU. Assay reproducibility was examined by testing 10 replicates of C. pneumoniae DNA by each assay. All five assays showed excellent reproducibility at high levels of DNA, with scores of 10 out of 10 for 0.01 IFU, but exhibited decreased reproducibility for smaller numbers of C. pneumoniae IFU for all tests. Pairwise comparison of test results indicated that there was a significant difference between tests (Cochran Q = 32.0, P<0.001), with the PstI fragment (P<0.001) and 16S rRNA (P = 0.002) assays having lower reproducibility than the nested ompA and TETR assays. To further analyze assay sensitivity, C. pneumoniae-infected U-937 mononuclear cells were added to whole blood, and extracted mononuclear-cell DNA was tested by each assay. All five assays showed similar sensitivities, detecting 15 infected cells; three assays detected 3 infected cells, while all assays were negative at the next dilution (1.5 infected cells). A striking difference in performance of the five assays was seen, however, when PBMCs from CAD patients were tested for C. pneumoniae DNA. The ompA nested PCR detected C. pneumoniae DNA in 11 of 148 (7.4%) specimens, the 16S rRNA nested PCR detected 2 positives among the 148 specimens (1.4%) (P<0.001), and the other 3 assays detected no positive specimens (P<0.001, compared with the ompA assay). These results indicate that analytical sensitivity alone does not predict the ability of an assay to detect C. pneumoniae in whole-blood-derived PBMCs. Before standardized assays can be used in wide-scale epidemiological studies, further characterization of these assays will be required to improve our understanding of their performance in the detection of C. pneumoniae in clinical material.

Chlamydia pneumoniae infection of human endothelial cells induces proliferation of smooth muscle cells via an endothelial cell-derived soluble factor(s).

An association of Chlamydia pneumoniae with atherosclerosis and coronary heart disease has been determined epidemiologically and by the detection of C. pneumoniae organisms in atherosclerotic lesions in both humans and animal models of atherosclerosis. Previously, it has been shown that C. pneumoniae is capable of replicating in cell types found within atheromatous lesions, viz., endothelial cells, smooth muscle cells (SMC), and macrophages, yet the role of C. pneumoniae in the pathogenesis of atherosclerosis has not been determined. Since intimal thickening is a hallmark of atherosclerosis, we investigated whether C. pneumoniae infection of human umbilical vein endothelial cells (HUVEC) could induce the expression of a soluble factor(s) with mitogenic potential for SMC by using [3H]thymidine incorporation and direct cell counting. Conditioned medium harvested from HUVEC infected with C. pneumoniae stimulated SMC replication in a time- and dose-dependent fashion. Infection studies using various multiplicities of infection (MOIs) ranging from 0.001 to 1 demonstrated a dose-dependent production of the soluble factor(s). At an MOI of 1, SMC stimulation indices were 8.4 (P < 0.01) and 12.2 (P < 0.01) for conditioned media harvested at 24 and 48 h, respectively. To determine whether viable C. pneumoniae was required for production of the soluble factor(s), HUVEC were infected with heat-inactivated C. pneumoniae or with viable organisms in the presence of chloramphenicol. Both treatments produced stimulation indices similar to those for live C. pneumoniae in the absence of chloramphenicol (P > 0.05), indicating that the factor(s) was produced by HUVEC and not by C. pneumoniae and that signal transduction events following chlamydia endocytosis may be important in the production of a soluble factor(s). The ability of C. pneumoniae to elicit an endothelial cell-derived soluble factor(s) that stimulates SMC proliferation may be important in the pathogenesis of atherosclerosis.