Osteoarthritis of the hands, hips and knees in an Australian twin sample - Evidence of association with the aggrecan VNTR polymorphism

Age-related changes in the composition of the cartilage matrix may be associated with the development of osteoarthritis, a relatively late-onset disease characterised by the destruction of joint cartilage. In order to investigate whether differences in the VNTR polymorphic region of aggrecan affect cartilage functionality and therefore the development of osteoarthritis, we examined the aggrecan polymorphic genotypes of a sample of 134 Australian twins aged over 50 (including 34 monozygotic and 27 dizygotic twin pairs). Clinical measures of hand, hip and knee osteoarthritis, as well as self-reported bone and joint pain, were tested for association with the aggrecan polymorphism. The results were consistent with either a deleterious effect of allele 27, or a protective effect of alleles 25 and 28, providing some additional evidence for an association between the aggrecan VNTR polymorphism and osteoarthritis of the hands, hips and knees.

Evidence for a sub-morphological inflammatory process in the liver in haemochromatosis

Background/Aims: The role of cytokines in hepatic injury has been examined for many liver diseases however little is known of the cytokine involvement in haemochromatosis. The aim of the current study was to examine the hepatic gene expression of potential proinflammatory and profibrogenic cytokines in haemochromatosis. Methods: Interferon-gamma, interleukin-10, transforming growth factor-beta(1) and tumor necrosis factor-alpha mRNA expression was assessed in liver tissue from 20 haemochromatosis patients, eight controls and eight chronic hepatitis C patients. To assess the immunophenotype of the inflammatory infiltrate in haemochromatosis, liver sections were subjected to immunohistochemistry using markers for macrophages (CD68, HAM56, MAC387) or T cells (CD3 and CD45RO). Results: Interferon-gamma mRNA was increased in both haemochromatosis (0.29+/-0.08%, P=0.01) and hepatitis C patients (1.02+/-0.32%, P=0.03) compared to controls (0.04+/-0.01%). Interleukin-10 mRNA was significantly decreased in both haemochromatosis and hepatitis C patients (0.01+/-0.003%, P=0.008 and 0.03+/-0.015%, P=0.02, respectively) compared to controls (0.12+/-0.01%). CD3 positive T-cell number was significantly correlated with increasing hepatic iron concentration (r=0.56, P=0.03). Conclusions: This study has demonstrated a distinct pattern of cytokine gene expression in haemochromatosis, which resembles that of inflammatory conditions such as chronic hepatitis C. These factors may play a role in the development of iron-induced hepatic fibrosis in haemochromatosis. (C) 2003 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.

The AF-1 Domain of the Orphan Nuclear Receptor NOR-1 Mediates Trans-activation, Coactivator Recruitment, and Activation by the Purine Anti-metabolite 6-Mercaptopurine

NOR-1/NR4A3 is an orphan member of the nuclear hormone receptor superfamily. NOR-1 and its close relatives Nurr1 and Nur77 are members of the NR4A subgroup of nuclear receptors. Members of the NR4A subgroup are induced through multiple signal transduction pathways. They have been implicated in cell proliferation, differentiation, T-cell apoptosis, chondrosarcomas, neurological disorders, inflammation, and atherogenesis. However, the mechanism of transcriptional activation, coactivator recruitment, and agonist-mediated activation remain obscure. Hence, we examined the molecular basis of NOR-1-mediated activation. We observed that NOR-1 trans-activates gene expression in a cell- and target-specific manner; moreover, it operates in an activation function (AF)-1-dependent manner. The N-terminal AF-1 domain delimited to between amino acids 1 and 112, preferentially recruits the steroid receptor coactivator (SRC). Furthermore, SRC-2 modulates the activity of the AF-1 domain but not the C-terminal ligand binding domain (LBD). Homology modeling indicated that the NOR-1 LBD was substantially different from that of hRORbeta, a closely related AF-2-dependent receptor. In particular, the hydrophobic cleft characteristic of nuclear receptors was replaced with a very hydrophilic surface with a distinct topology. This observation may account for the inability of this nuclear receptor LBD to efficiently mediate cofactor recruitment and transcriptional activation. In contrast, the N-terminal AF-1 is necessary for cofactor recruitment and can independently conscript coactivators. Finally, we demonstrate that the purine anti-metabolite 6-mercaptopurine, a widely used antineoplastic and anti-inflammatory drug, activates NOR-1 in an AF-1-dependent manner. Additional 6-mercaptopurine analogs all efficiently activated NOR-1, suggesting that the signaling pathways that modulate proliferation via inhibition of de novo purine and/or nucleic acid biosynthesis are involved in the regulation NR4A activity. We hypothesize that the NR4A subgroup mediates the genotoxic stress response and suggest that this subgroup may function as sensors that respond to genotoxicity.

Sex- and race-related differences in cross-sectional geometry and bone density of the femoral mid-shaft in older adults

Background : Femoral shaft fracture incidence increases in older adults and is associated with low-energy trauma. Apart from bone density, the distribution and size of bone contributes to its strength. Aim : To examine if bone geometry and density of the femoral mid-shaft in older adults differs by sex and race, we studied 197 White women, 225 Black women, 242 White men, and 148 Black men aged 70-79 years participating in the Health, Aging, and Body Composition study; a prospective cohort study in the USA. A secondary purpose of the study was to examine the association of site-specific muscle and fat to bone geometry and density. Subjects and methods : Subjects were community-dwelling and reported no difficulty walking one-quarter of a mile or climbing stairs. Mid-femoral volumetric bone mineral density (vBMD, mg cm -3 ), total area (TA), cortical area (CA), medullary area (MA), cross-sectional moments of inertia (CSMI: I x , I y , J ), and muscle and fat areas (cm 2 ) were determined by computed tomography (CT; GE CT-9800, 10 mm slice thickness). Results : vBMD was greater in men than women with no difference by race ( p < 0.001). Bone areas and area moments of inertia were also greater in men than women ( p < 0.001), with Black women having higher values than White women for TA and CA. Standardizing geometric parameters for body size differences by dividing by powers of femur length did not negate the sex difference for TA and MA. Significant differences ( p < 0.05) among the four groups also remained for I x and J . Mid-thigh muscle area was an independent contributor to TA in all groups (Std beta = 0.181-0.351, p < 0.05) as well as CA in women (Std beta = 0.246-0.254, p < 0.01) and CSMI in White women (Std beta = 0.175-0.185, p < 0.05). Further, muscle area was a significant contributor to vBMD in Black women. Conclusion : These results indicate that bone geometry and density of the femoral diaphysis differs primarily by sex, rather than race, in older well-functioning adults. In addition, site-specific muscle area appears to have a potential contributory role to bone geometry parameters, especially in women.

Influence of environmental temperature and humidity on the acute ventilatory response to exercise in asthmatic adolescents

Asthma is a chronic inflammatory disorder of the respiratory airways affecting people of all ages, and constitutes a serious public health problem worldwide (6). Such a chronic inflammation is invariably associated with injury and repair of the bronchial epithelium known as remodelling (11). Inflammation, remodelling, and altered neural control of the airways are responsible for both recurrent exacerbations of asthma and increasingly permanent airflow obstruction (11, 29, 34). Excessive airway narrowing is caused by altered smooth muscle behaviour, in close interaction with swelling of the airway walls, parenchyma retractile forces, and enhanced intraluminal secretions (29, 38). All these functional and structural changes are associated with the characteristic symptoms of asthma – cough, chest tightness, and wheezing –and have a significant impact on patients’ daily lives, on their families and also on society (1, 24, 29). Recent epidemiological studies show an increase in the prevalence of asthma, mainly in industrial countries (12, 25, 37). The reasons for this increase may depend on host factors (e.g., genetic disposition) or on environmental factors like air pollution or contact with allergens (6, 22, 29). Physical exercise is probably the most common trigger for brief episodes of symptoms, and is assumed to induce airflow limitations in most asthmatic children and young adults (16, 24, 29, 33). Exercise-induced asthma (EIA) is defined as an intermittent narrowing of the airways, generally associated with respiratory symptoms (chest tightness, cough, wheezing and dyspnoea), occurring after 3 to 10 minutes of vigorous exercise with a maximal severity during 5 to 15 minutes after the end of the exercise (9, 14, 16, 24, 33). The definitive diagnosis of EIA is confirmed by the measurement of pre- and post-exercise expiratory flows documenting either a 15% fall in the forced expiratory volume in 1 second (FEV1), or a ≥15 to 20% fall in peak expiratory flow (PEF) (9, 24, 29). Some types of physical exercise have been associated with the occurrence of bronchial symptoms and asthma (5, 15, 17). For instance, demanding activities such as basketball or soccer could cause more severe attacks than less vigorous ones such as baseball or jogging (33). The mechanisms of exercise-induced airflow limitations seem to be related to changes in the respiratory mucosa induced by hyperventilation (9, 29). The heat loss from the airways during exercise, and possibly its post-exercise rewarming may contribute to the exercise-induced bronchoconstriction (EIB) (27). Additionally, the concomitant dehydration from the respiratory mucosa during exercise leads to an increased interstitial osmolarity, which may also contribute to bronchoconstriction (4, 36). So, the risk of EIB in asthmatically predisposed subjects seems to be higher with greater ventilation rates and the cooler and drier the inspired air is (23). The incidence of EIA in physically demanding coldweather sports like competitive figure skating and ice hockey has been found to occur in up to 30 to 35% of the participants (32). In contrast, swimming is often recommended to asthmatic individuals, because it improves the functionality of respiratory muscles and, moreover, it seems to have a concomitant beneficial effect on the prevalence of asthma exacerbations (14, 26), supporting the idea that the risk of EIB would be smaller in warm and humid environments. This topic, however, remains controversial since the chlorified water of swimming pools has been suspected as a potential trigger factor for some asthmatic patients (7, 8, 20, 21). In fact, the higher asthma incidence observed in industrialised countries has recently been linked to the exposition to chloride (7, 8, 30). Although clinical and epidemiological data suggest an influence of humidity and temperature of the inspired air on the bronchial response of asthmatic subjects during exercise, some of those studies did not accurately control the intensity of the exercise (2, 13), raising speculation of whether the experienced exercise overload was comparable for all subjects. Additionally, most of the studies did not include a control group (2, 10, 19, 39), which may lead to doubts about whether asthma per se has conditioned the observed results. Moreover, since the main targeted age group of these studies has been adults (10, 19, 39), any extrapolation to childhood/adolescence might be questionable regarding the different lung maturation. Considering the higher incidence of asthma in youngsters (30) and the fact that only the works of Amirav and coworkers (2, 3) have focused on this age group, a scarcity of scientific data can be identified. Additionally, since the main environmental trigger factors, i.e., temperature and humidity, were tested separately (10, 28, 39) it would be useful to analyse these two variables simultaneously because of their synergic effect on water and heat loss by the airways (31, 33). It also appears important to estimate the airway responsiveness to exercise within moderate environmental ranges of temperature and humidity, trying to avoid extreme temperatures and humidity conditions used by others (2, 3). So, the aim of this study was to analyse the influence of moderate changes in air temperature and humidity simultaneously on the acute ventilatory response to exercise in asthmatic children. To overcome the above referred to methodological limitations, we used a 15 minute progressive exercise trial on a cycle ergometer at 3 different workload intensities, and we collected data related to heart rate, respiratory quotient, minute ventilation and oxygen uptake in order to ensure that physiological exercise repercussions were the same in both environments. The tests were done in a “normal” climatic environment (in a gymnasium) and in a hot and humid environment (swimming pool); for the latter, direct chloride exposition was avoided.

Q192R polymorphism of the paraoxonase-1 gene as a risk factor for obesity in Portuguese women

Introduction - Obesity became a major public health problem as a result of its increasing prevalence worldwide. Paraoxonase-1 (PON1) is an esterase able to protect membranes and lipoproteins from oxidative modifications. At the PON1 gene, several polymorphisms in the promoter and coding regions have been identified. The aims of this study were i) to assess PON1 L55M and Q192R polymorphisms as a risk factor for obesity in women; ii) to compare PON1 activity according to the expression of each allele in L55M and Q192R polymorphisms; iii) to compare PON1 activity between obese and normal-weight women. Materials and methods - We studied 75 healthy (35.9±8.2 years) and 81 obese women (34.3±8.2 years). Inclusion criteria for obese subjects were body mass index ≥30 kg/m2 and absence of inflammatory/neoplasic conditions or kidney/hepatic dysfunction. The two PON1 polymorphisms were assessed by real-time PCR with TaqMan probes. PON1 enzymatic activity was assessed by spectrophotometric methods, using paraoxon as a substrate. Results - No significant differences were found for PON1 activity between normal and obese women. Nevertheless, PON1 activity was greater (P<0.01) for the RR genotype (in Q192R polymorphism) and for the LL genotype (in L55M polymorphism). The frequency of allele R of Q192R polymorphism was significantly higher in obese women (P<0.05) and was associated with an increased risk of obesity (odds ratio=2.0 – 95% confidence interval (1.04; 3.87)). Conclusion - 55M and Q192R polymorphisms influence PON1 activity. The allele R of the Q192R polymorphism is associated with an increased risk for development of obesity among Portuguese Caucasian premenopausal women.

Inoculation of Lacazia loboi into the subcutaneous tissue of the hamster cheek pouch

The subcutaneous tissue of the hamster cheek pouch, a site of immunologic privilege, has been used to investigate the potential infectivity of different types of parasites. It has been demonstrated that the implantation of fragments of lesions induced by the fungus Lacazia loboi, the etiologic agent of Jorge Lobo's disease, into the subcutaneous tissue of the hamster cheek pouch resulted in parasite multiplication and dissemination to satellite lymph nodes16. Here we describe the evolution of lesions induced by the inoculation of the isolated fungus into this immunologically privileged site. The morphology of the inflammatory response and fungal viability and proliferation were evaluated. Inoculation of the fungus into the cheek pouch induced histiocytic granulomas with rare lymphocytes. Although fungal cells were detected for a period of up to 180 days in these lesions, the fungi lost viability after the first day of inoculation. In contrast, when the parasite was inoculated into the footpad, non-organized histiocytic lesions were observed. Langhan's giant cells, lymphocytes and fungal particles were observed in these lesions. Fungal viability was observed up to 60 days after inoculation and non-viable parasites were present in the persistent lesions up to 180 days post-inoculation. These data indicate that the subcutaneous tissue of the hamster cheek pouch is not a suitable site for the proliferation of Lacazia loboi when the fungus isolated from human tissues is tested.

Neurologic cytomegalovirus complications in patients with AIDS: retrospective review of 13 cases and review of the literature

Neurological disorders caused by Cytomegalovirus (CMV) in patients with Acquired Immunodeficiency Syndrome (AIDS) are rarely reported in the Highly Active Antiretroviral Therapy (HAART) period. The objective of this study was to describe the main clinical and laboratory features of patients with CMV-related neurological complications in HIV-infected patients admitted to a referral center in São Paulo, Brazil. CMV disease requires the identification of the virus in the cerebrospinal fluid (CSF) using Polymerase Chain Reaction (PCR). Thirteen cases were identified between January, 2004 and December, 2008. The median age of patients was 38 years and nine (69%) were men. At admission all patients were aware of their HIV status and only four (31%) patients were on HAART. Patients who were not on antiretroviral therapy before admission received HAART while inpatients. CMV disease was the first AIDS-defining illness in eight (62%) patients. The neurologic syndromes identified were diffuse encephalitis (n = 7; 62%), polyradiculopathy (n = 7; 54%), focal encephalitis (rhombencephalitis) (n = 1; 8%), and ventriculo-encephalitis (n = 1; 8%). Seven (54%) patients presented extra-neural CMV disease and four (31%) had retinitis. The median of CD4+ T-cell count was 13 cells/µL (range: 1-124 cells/µL). Overall in-hospital mortality was 38%. Eight patients used ganciclovir or foscarnet (in-hospital mortality: 50%) and five patients used ganciclovir and foscarnet (in-hospital mortality: 20%). None of the patients fulfilled the diagnosis criteria of immune reconstitution inflammatory syndrome. Four patients were lost to follow-up, and three patients presented immune recovery and discontinued secondary prophylaxis. Although infrequent, distinct neurological syndromes caused by CMV continue to cause high mortality among AIDS patients. Survival depends upon the use of effective antiviral therapy against CMV and the early introduction of HAART.

Adenocarcinoma of the Ileum: A Rare and Challenging Entity

INTRODUCTION: Primary small bowel malignancy is unusual and accounts for 1-3% of all gastrointestinal tract neoplasms. Adenocarcinoma is one of the most common histologic types, but its frequency decreases with more distal locations. Its clinical presentation is nonspecific and is usually associated with advanced disease, which contributes to delayed diagnosis. PRESENTATION OF CASE: A 66-year-old woman was admitted to the hospital with a 6-day history of progressively worsening abdominal pain localized in the right lower quadrant, nausea, and vomiting. Investigation revealed an inflammatory appendiceal tumor. The patient underwent surgery and an unexpected tumor involving the distal ileal segment and ileocecal appendix was found. Right radical hemicolectomy with en bloc resection of the distal ileum was performed. Histopathological examination revealed adenocarcinoma of the ileum. DISCUSSION: This rare entity is associated with a nonspecific clinical presentation that contributes to delayed diagnosis and treatment, and consequently to a worse prognosis. Approximately half of the cases are only diagnosed at surgery. Primary treatment consists of wide resection with locoregional lymphadenectomy. The role of adjuvant chemotherapy has yet to be determined. CONCLUSION: This case demonstrates an unusual condition characterized by late and challenging diagnosis. We highlight the importance of an earlier diagnosis and optimal treatment for improved patient outcomes.

Effectiveness of the Dexamethasone Intravitreal Implant for Treatment of Patients with Diabetic Macular Oedema

Diabetic macular oedema (DMO) is a leading cause of vision loss in the working-age population worldwide. Corticosteroid drugs have been demonstrated to inhibit the expression of both the vascular endothelial growth factor (VEGF) gene and other anti-inflammatory mediators, such as prostaglandins. Triamcinolone, fluocinolone and dexamethasone are the main steroids that have been studied for the treatment of macular oedema. Over the last few years, several studies have suggested an important role for dexamethasone in the management of DMO. The dexamethasone intravitreal implant (DEX implant) (Ozurdex®; Allergan, Inc., Irvine, CA) is a novel approach approved by the US Food and Drug Administration (FDA) and by the EU for the intravitreal treatment of macular oedema after branch or central retinal vein occlusion, and for the treatment of non-infectious uveitis affecting the posterior segment of the eye. We reviewed manuscripts that had investigated the pharmacokinetics, efficacy and safety of the DEX implant regarding DMO treatment.

Quantification and characterization of the phenolic compounds of kenaf leaves

Dissertation for the Master Degree in Technology and Food Security

Pseudoneoplastic lesion of the breast caused by Schistosoma mansoni

A case of a pseudoneoplastic lesion of the breast clinically and sonographically suggestive of a fibroadenoma is reported. Excisional biopsy revealed the nodule was an inflammatory process consequent to infection by Schistosoma mansoni.

Megabladder in experimental Chagas disease: pathological features of the bladder wall

Mega-organs, primarily in the digestive tract, are well known to occur in chronic Chagas disease. Acute experimental infection with Trypanosoma cruzi results in parasitism of a wide range of cells, tissues, and organs, including the urinary bladder. Infection of BALB/c mice with 100,000 bloodstream forms of the Y strain of T. cruzi induced acute infection with intense parasitism of all layers of the urinary bladder. Parasites were found in the mucosa, lamina propria, muscular, adventitial connective, and fat tissue. Desquamate epithelial cells with amastigotes in the bladder lumen were also found. After 60 days of infection, mice inoculated with 50 bloodstream forms developed dilated, thin-walled bladders that had inflammatory infiltrates and foci of fibrosis replacing areas of damaged muscular layer. These lesions result from direct damage to the muscle fibers by the T. cruzi, leading to myosites, muscle damage, and scarring. Direct damage of paraganglia cells secondary to parasitism, leading to dilatation, damage of muscle fibers, and scarring with replacement of muscular tissue with connective tissue, should also be considered as a cause of functional disturbance of the urinary bladder.

Modulation of the secretome of hBMSCs by tailoring the macromolecular gradient in hydrogels to generate tissue-to-tissue interfaces

Tissue-to-tissue interfaces are commonly present in all tissues exhibiting structural, biological and chemical gradients serving a wide range of physiological functions. These interfaces are responsible for mediation of load transfer between two adjacent tissues. They are also important structures in sustaining the cellular communications to retain tissueâ s functional integration and homeostasis. [1] All cells have the capacity to sense and respond to physical and chemical stimulus and when cultured in three-dimensional (3D) environments they tend to perform their function better than in two-dimensional (2D) environments. Spatial and temporal 3D gradient hydrogels better resemble the natural environment of cells in mimicking their extracellular matrix. [2] In this study we hypothesize that differential functional properties can be engineered by modulation of macromolecule gradients in a cell seeded threedimensional hydrogel system. Specifically, differential paracrine secretory profiles can be engineered using human Bone Marrow Stem Cells (hBMSCâ s). Hence, the specific objectives of this study are to: assemble the macromolecular gradient hydrogels to evaluate the suitablity for hBMSCâ s encapsulation by cellular viability and biofunctionality by assessing the paracrine secretion of hBMSCâ s over time. The gradient hydrogels solutions were prepared by blend of macromolecules in one solution such as hyaluronic (HA) acid and collagen (Col) at different ratios. The gradient hydrogels were fabricated into cylindrical silicon moulds with higher ratio solutions assembled at the bottom of the mould and adding the two solutions consecutively on top of each other. The labelling of the macromolecules was performed to confirm the gradient through fluorescence microscopy. Additionally, AFM was conducted to assess the gradient hydrogels stiffness. Gradient hydrogels characterization was performed by HA and Col degradation assay, degree of crosslinking and stability. hBMSCâ s at P3 were encapsulated into each batch solution at 106 cells/ml solution and gradient hydrogels were produced as previously described. The hBMSCâ s were observed under confocal microscopy to assess viability by Live/Dead® staining. Cellular behaviour concerning proliferation and matrix deposition was also performed. Secretory cytokine measurement for pro-inflammatory and angiogenesis factors was carried out using ELISA. At genomic level, qPCR was carried out. The 3D gradient hydrogels platform made of different macromolecules showed to be a suitable environment for hBMSCâ s. The hBMSCâ s gradient hydrogels supported high cell survival and exhibited biofunctionality. Besides, the 3D gradient hydrogels demonstrated differentially secretion of pro-inflammatory and angiogenic factors by the encapsulated hBMSCâ s. References: 1. Mikos, AG. et al., Engineering complex tissues. Tissue Engineering 12,3307, 2006 2. Phillips, JE. et al., Proc Natl Acad Sci USA, 26:12170-5, 2008

A review of squeaking in ceramic total hip prostheses

The occurrence of audible squeaking in some patients with ceramic-on-ceramic (CoC) hip prostheses is a cause for concern. Considering multifactor contributing to this phenomenon, many studies have been conducted over the last decade. Great efforts have been put on understanding the mechanics of the hip squeaking to gain a deep insight into factors resulting in sound emission from hip articulation. Disruption of fluid-film lubrication and friction were reported as main potential causes of hip squeaking, while patient and surgical factors as well as design and material of hip implants were identified as affecting factors. This review article therefore summarised the recent available literature on this subject to provide a platform for future developments. Moreover, high wear rates and ceramic liner fracture as viable consequences of hip squeaking were discussed.