Trabecular and cortical bone involvement in rheumatoid arthritis by DXA and DXA-based 3D modelling.

Rheumatoid arthritis (RA) patients had a higher risk of developing low bone mineral density (BMD) or osteoporosis. RA patients on classic disease-modifying antirheumatic drug (c-DMARD) therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving biological disease-modifying antirheumatic drugs (b-DMARDs) and controls. The 3D analysis allowed us to find changes in the trabecular and cortical compartments. INTRODUCTION: To evaluate cortical and trabecular bone involvement of the hip in RA patients by dual-energy X-ray absorptiometry (DXA) and 3D analysis. The secondary end-point was to evaluate bone involvement in patients treated with classic (c-DMARD) or biological (b-DMARD) disease-modifying antirheumatic drug therapies and the effect of the duration of the disease and corticosteroid therapy on 3D parameters. METHODS: A cross-sectional study of 105 RA patients and 100 subjects as a control group (CG) matched by age, sex, and BMI was carried out. BMD was measured by DXA of the bilateral femoral neck (FN) and total hip (TH). The 3D analyses including trabecular and cortical BMD were performed on hip scans with the 3D-Shaper software. RESULTS: FN and TH BMD and trabecular and cortical vBMD were significantly lower in RA patients. The c-DMARD (n = 75) group showed significantly lower trabecular and cortical vBMD than the CG. Despite the lower values, the b-DMARD group (n = 30) showed no significant differences in most parameters compared with the CG. The trabecular and cortical 3D parameters were significantly lower in the group with an RA disease duration of 1 to 5 years than in the CG, and the trabecular vBMD was significantly lower in the group with a duration of corticosteroid therapy of 1 to 5 years than in the CG, while no significant differences were found by standard DXA in the same period. CONCLUSIONS: RA patients had a higher risk of developing low BMD or osteoporosis than controls. RA patients receiving c-DMARD therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving b-DMARDs and controls. 3D-DXA allowed us to find changes in trabecular and cortical bone compartments in RA patients.

Density assessment and reporting for Phlebotomus perniciosus and other sand fly species in periurban residential estates in Spain.

Green periurban residential areas in Mediterranean countries have flourished in the last decades and become foci for leishmaniasis. To remedy the absence of information on vector ecology in these environments, we examined phlebotomine sand fly distribution in 29 sites in Murcia City over a 3-year period, including the plots of 20 detached houses and nine non-urbanized sites nearby. We collected 5,066 specimens from five species using "sticky" interception and light attraction traps. The relative frequency of the main Leishmania infantum vector Phlebotomus perniciosus in these traps was 32% and 63%, respectively. Sand fly density was widely variable spatially and temporally and greatest in non-urbanized sites, particularly in caves and abandoned buildings close to domestic animal holdings. Phlebotomus perniciosus density in house plots was positively correlated with those in non-urbanized sites, greatest in larger properties with extensive vegetation and non-permanently lived, but not associated to dog presence or a history of canine leishmaniasis. Within house plots, sand fly density was highest in traps closest to walls. Furthermore, the study provides a guideline for insect density assessment and reporting and is envisioned as a building block towards the development of a pan-European database for robust investigation of environmental determinants of sand fly distribution.

Effects of osteoporosis drug treatments on cortical and trabecular bone in the femur using DXA-based 3D modeling.

Effects of osteoporosis drugs on proximal femur cortical and trabecular bone were studied using dual-energy x-ray absorptiometry (DXA)-based 3D modeling method. Changes observed in this head-to-head study were consistent with those obtained using computed tomography in the literature. INTRODUCTION: The aim of the present study was to assess the effects of osteoporosis drugs on cortical and trabecular bone at the proximal femur using DXA-based 3D modeling. METHODS: We retrospectively analyzed 155 patients stratified by treatments: naive of treatment (NAIVE), alendronate (AL), denosumab (DMAB), and teriparatide (TPTD). DXA scans were performed at baseline and after treatment, and areal bone mineral density at spine and femur were measured. A software algorithm (3D-SHAPER) was used to derive 3D models from hip DXA scans and compute: trabecular and cortical volumetric BMD (vBMD), cortical thickness (Cth), and cortical surface BMD (cortical sBMD). Changes from baseline were normalized at 24 months and evaluated in terms or percentage. RESULTS: After 24 months, a non-significant decrease was observed for trabecular vBMD, Cortical sBMD, Cth, and cortical vBMD (- 2.3, - 0.8, - 0.3, and - 0.5%) in the NAIVE group. Under AL and DMAB, significant increases were observed in trabecular vBMD (3.8 and 7.3%), cortical vBMD (1.4 and 2.0%), and cortical sBMD (1.5 and 3.6%). An increase in Cth was observed in patients under DMAB (1.8%). Under TPTD, a significant increase in Trabecular vBMD was observed (5.9%) associated with a non-significant increase of Cth (+ 1%) concomitant with a decrease in cortical vBMD (- 1.1%). CONCLUSION: Results obtained in this head-to-head study are consistent with those obtained using computed tomography in the literature. DXA-based modeling techniques could complement standard DXA examination to monitor treatment effects on trabecular and cortical compartments.

Analysis of the evolution of cortical and trabecular bone compartments in the proximal femur after spinal cord injury by 3D-DXA.

Marked trabecular and cortical bone loss was observed at the proximal femur short-term after spinal cord injury (SCI). 3D-DXA provided measurement of vBMD evolution at both femoral compartments and cortical thinning, thereby suggesting that this technique could be useful for bone analysis in these patients. INTRODUCTION: SCI is associated with a marked increase in bone loss and risk of osteoporosis development short-term after injury. 3D-DXA is a new imaging analysis technique providing 3D analysis of the cortical and trabecular bone from DXA scans. The aim of this study was to assess the evolution of trabecular macrostructure and cortical bone using 3D-DXA in patients with recent SCI followed over 12 months. METHODS: Sixteen males with recent SCI (< 3 months since injury) and without antiosteoporotic treatment were included. Clinical assessment, bone mineral density (BMD) measurements by DXA, and 3D-DXA evaluation at proximal femur (analyzing the integral, trabecular and cortical volumetric BMD [vBMD] and cortical thickness) were performed at baseline and at 6 and 12 months of follow-up. RESULTS: vBMD significantly decreased at integral, trabecular, and cortical compartments at 6 months (- 8.8, - 11.6, and - 2.4%), with a further decrease at 12 months, resulting in an overall decrease of - 16.6, - 21.9, and - 5.0%, respectively. Cortical thickness also decreased at 6 and 12 months (- 8.0 and - 11.4%), with the maximal decrease being observed during the first 6 months. The mean BMD losses by DXA at femoral neck and total femur were - 17.7 and - 21.1%, at 12 months, respectively. CONCLUSIONS: Marked trabecular and cortical bone loss was observed at the proximal femur short-term after SCI. 3D-DXA measured vBMD evolution at both femoral compartments and cortical thinning, providing better knowledge of their differential contributory role to bone strength and probably of the effect of therapy in these patients.

Improvement of lipoatrophy by switching from efavirenz to lopinavir/ritonavir.

OBJECTIVE: To assess whether changes in antiretroviral drugs other than thymidine nucleoside reverse transcriptase inhibitors (NRTI) may have a body fat impact in HIV-infected patients with lipoatrophy. METHODS: Ninety-six-week phase IV, open-label, multicentre, pilot randomized trial. HIV-infected patients with moderate/severe lipoatrophy at one or more body sites despite long-term thymidine NRTI-free therapy were randomized to continue their efavirenz (EFV)-based antiretroviral regimen or to switch from EFV to lopinavir/ritonavir (LPV/r). The primary endpoint was the absolute change in limb fat mass measured by dual X-ray absorptiometry from baseline to 96 weeks. Changes in other body fat measurements, subjective perception of lipoatrophy, subcutaneous fat gene expression and plasma lipids were also assessed. RESULTS: Thirty-three patients (73% men, median age 52 years) were recruited. At 96 weeks, absolute limb fat mass increased in the LPV/r arm vs. the EFV arm (estimated difference +1082.1 g; 95% CI +63.7 to +2103.5; P = 0.04); this difference remained significant after adjustment by gender, age, fat mass, body mass index and CD4 cell count at baseline. Subjective lipoatrophy perception scores also improved in the LPV/r arm relative to the EFV arm. Adipogenesis, glucose and lipid metabolism, and mitochondrial gene expression increased in the LPV/r arm compared with the EFV arm at 96 weeks. HDL cholesterol decreased in the LPV/r arm relative to the EFV arm. CONCLUSIONS: Switching from EFV to LPV/r in HIV-infected patients with lipoatrophy may offer further limb fat gain beyond thymidine NRTI discontinuation, although this strategy decreased plasma HDL cholesterol and caused changes in subcutaneous fat gene expression that may be associated with increased insulin resistance.

Comparison of two different strategies of treatment with zoledronate in HIV-infected patients with low bone mineral density: single dose versus two doses in 2 years.

OBJECTIVES: Given the need for easily managed treatment of osteoporosis in HIV-infected patients, we evaluated the efficacy and tolerability of two doses of zoledronate, by comparing three groups of patients: those with annual administration, those with biennial administration (one dose in 2 years) and a control group with no administration of zoledronate. METHODS: We randomized (2:1) 31 patients on antiretroviral therapy with low bone mineral density (BMD) to zoledronate (5 mg administered intravenously; 21 patients) plus diet counselling and to a control group (diet counselling; 10 patients). At week 48, patients treated with zoledronate were randomized again to receive a second dose (two-dose group; n = 12) or to continue with diet counselling only (single-dose group; n = 9). Changes in lumbar spine and hip BMD and bone turnover markers were compared. RESULTS: The median percentage change from baseline to week 96 in L1-L4 BMD was -1.74% [interquartile range (IQR) -2.56, 3.60%], 7.90% (IQR 4.20, 16.57%) and 5.22% (IQR 2.02, 7.28%) in the control, two-dose and single-dose groups, respectively (P < 0.01, control vs. two doses; P = 0.02, control vs. single dose; P = 0.18, two doses vs. single dose). Hip BMD changed by a median of 2.12% (IQR -0.12, 3.08%), 5.16% (IQR 3.06, 6.74%) and 4.47% (IQR 1, 5.58%), respectively (P = 0.04, control vs. two doses; P = 0.34, two doses vs. single dose). No differences between the two-dose and single-dose groups were detected in bone markers at week 96. CONCLUSIONS: The benefits for BMD of a single dose of zoledronate in 2 years may be comparable to those obtained with two doses of the drug after 96 weeks, although this study is insufficiently powered to exclude a real difference. Future studies should explore whether biennial administration of zoledronate is a useful alternative in the treatment of osteoporosis in HIV-infected patients.

Prevalence of vertebral fractures and minor vertebral deformities evaluated by DXA-assisted vertebral fracture assessment (VFA) in a population-based study of postmenopausal women: the FRODOS study.

UNLABELLED: Population-based studies performed with vertebral fracture assessment (VFA) morphometric technology are lacking in postmenopausal osteoporosis. In this study, we show a lower than expected prevalence of vertebral fractures, a high prevalence of minor vertebral deformities, and a clear association with clinical and densitometric parameters indicating the usefulness of this approach. INTRODUCTION: Adequate epidemiological data on the prevalence of vertebral fractures (VF) is essential in studies of postmenopausal osteoporosis. Routine DXA-assisted VFA may be useful to determine the presence of VF. However, population-based studies performed with this technology are lacking. We aimed to assess the prevalence of VF and minor deformities in 2,968 postmenopausal women aged 59-70 years from a population-based cohort. METHODS: VFA and bone mineral density (BMD) measurements were conducted, and McCloskey criteria (vertebral heights under 3 SD from reference values) confirmed with the Genant method were used to define VF. Additionally, minor vertebral deformities (vertebral heights between -2 and -2.99 SD) were evaluated. RESULTS: The prevalence of VF was 4.3%, and 17% of the participants had minor vertebral deformities. Low BMD was frequently observed in women with VF, with 4%, and 42% of participants showing osteoporosis and osteopenia. Minor vertebral deformities were observed in nearly 40% of women with VF. Multivariate logistic regression analysis showed that age, history of previous fracture, osteoporotic BMD, receiving anti-osteoporotic treatment, and current use of glucocorticoids were significantly associated with VF. CONCLUSIONS: Although the VFA approach showed a lower than expected prevalence of VF in our cohort, its association with clinical and densitometric parameters may be useful to identify women at risk for developing fragility fractures and may therefore justify its use in longitudinal studies. The high prevalence of minor vertebral deformities detected in patients with VF indicates the need to evaluate this type of deformity as a risk factor for further skeletal fractures.

IFN-γ expression in placenta is associated to resistance to Chlamydia abortus after intragastric infection.

Intragastric infection mimics the natural route of infection of Chlamydia abortus (etiological agent of ovine enzootic abortion). In the mouse model, intragastric experimental infection induces very mild signs of infection followed by late term abortions, as it is shown by the natural ovine host. In order to evaluate the immune mechanisms associated to the dissemination of the pathogen from the gastrointestinal tract, we have administered an intragastric dose of C. abortus to pregnant mice. Systemic and local expression of cytokines, tissue colonization and excretion of bacteria after parturition were monitored during pregnancy. Susceptible CBA/J mice showed a higher bacterial colonization of the placenta and excretion of live bacteria after parturition that were related to a higher local IL-10 expression. By contrast, resistant C57BL/6 mouse strain had higher local IFN-γ mRNA expression in the placenta just before parturition and a transient bacterial colonization of the reproductive tract, with no excretion of C. abortus after parturition. In summary, intragastric infection not only mimics the natural route of infection of C. abortus, but can also be useful in order to understand the immunopathogenesis of chlamydial abortion in the mouse.

Is bone microarchitecture status of the lumbar spine assessed by TBS related to femoral neck fracture? A Spanish case-control study.

UNLABELLED: Bone mineral density (BMD) as assessed by dual energy X-ray absorptiometry (DXA) constitutes the gold standard for osteoporosis diagnosis. However, DXA does not take into account bone microarchitecture alterations. INTRODUCTION: The aim of our study was to evaluate the ability of trabecular bone score (TBS) at lumbar spine to discriminate subjects with hip fracture. METHODS: We presented a case-control study of 191 Spanish women aged 50 years and older. Women presented transcervical fractures only. BMD was measured at lumbar spine (LS-BMD) using a Prodigy densitometer. TBS was calculated directly on the same spine image. Descriptive statistics, tests of difference and univariate and multivariate backward regressions were used. Odds ratio (OR) and the ROC curve area of discriminating parameters were calculated. RESULTS: The study population consisted of 83 subjects with a fracture and 108 control subjects. Significant lower spine and hip BMD and TBS values were found for subjects with fractures (p < 0.0001). Correlation between LS-BMD and spine TBS was modest (r = 0.41, p < 0.05). LS-BMD and TBS independently discriminate fractures equally well (OR = 2.21 [1.56-3.13] and 2.05 [1.45-2.89], respectively) but remain lower than BMD at neck or at total femur (OR = 5.86 [3.39-10.14] and 6.06 [3.55-10.34], respectively). After adjusting for age, LS-BMD and TBS remain significant for transcervical fracture discrimination (OR = 1.94 [1.35-2.79] and 1.71 [1.15-2.55], respectively). TBS and LS-BMD combination (OR = 2.39[1.70-3.37]) improved fracture risk prediction by 25 %. CONCLUSION: This study shows the potential of TBS to discriminate subjects with and without hip fracture. TBS and LS-BMD combination improves fracture risk prediction. Nevertheless, BMD at hip remains the best predictor of hip fracture.

Patients with cirrhosis and ascites have false values of bone density: implications for the diagnosis of osteoporosis.

UNLABELLED: The effect of ascites on bone densitometry has been assessed in 25 patients with advanced cirrhosis, and it was concluded that ascites over 4 l causes inaccuracy of BMD measurements, particularly at the lumbar spine. This fact must be considered when assessing bone mass in patients with decompensated cirrhosis. INTRODUCTION: Bone mineral density (BMD) measured by dual-energy x-ray absorptiometry (DXA) is the best procedure for assessment of osteoporosis and fracture risk, but BMD values at the central skeleton may be influenced by changes in soft tissues. Therefore, we have studied the effect of ascites on BMD. METHODS: BMD was measured by DXA at the lumbar spine, femoral neck and total hip, just before and shortly after therapeutic paracentesis in 25 patients with advanced liver cirrhosis. Changes in BMD, lean and fat mass, abdominal diameter and weight, as well as the amount of removed ascites were measured. RESULTS: The amount of drained ascites was 6.6 ± 0.5 l (range: 3.0 to 12.7 l). After paracentesis, BMD increased at the lumbar spine (from 0.944 ± 0.035 to 0.997 ± 0.038 g/cm(2), p < 0.001) and at the total hip (from 0.913 ± 0.036 to 0.926 ± 0.036 g/cm(2), p < 0.01). Patients with a volume of drained ascites higher than 4 l showed a significant increase in lumbar BMD (7.0%), compared with patients with a lower amount (1.5%) (p < 0.03). The decrease in total soft tissue mass correlated with the amount of removed ascites (r = 0.951, p < 0.001). Diagnosis of osteoporosis or osteopenia changed after paracentesis in 12% of patients. CONCLUSION: Ascites over 4 l causes inaccuracy of BMD measurements, particularly at the lumbar spine. This fact must be considered when assessing bone mass in patients with advanced cirrhosis.

Tinnitus and quality of life following vestibular schwannoma surgery.

OBJECTIVE: This study on patients undergoing surgery for vestibular schwannoma investigated tumour (i) the effect of pre-operative factors on tinnitus, (ii) the effect of translabyrinthine or hearing preservation surgical approaches on tinnitus, and (iii) the effect of postoperative tinnitus status on the patient's quality of life (QOL). METHODOLOGY: Seventy-nine patients who underwent vestibular schwannoma (VS) excision between 2001 and 2005 were selected. Postoperative tinnitus status was evaluated using a standard questionnaire for tinnitus, and QOL was measured using the Glasgow Benefit Inventory (GBI). RESULTS: Overall, 58% of patients noted tinnitus before tumour removal. Pre-operative tinnitus was not associated with age, gender, tumour size, or hearing thresholds. The total percentage of patients suffering postoperative tinnitus was 64%. Hearing preservation approaches showed no difference in terms of changes in tinnitus compared to the translabyrinthine approach. Twenty-one patients (30%) reported better QOL, 40 patients (56%) reported worse QOL, and 10 patients (14%) reported the same QOL. A significant association was found between tinnitus worsening as measured by GBI score and QOL. CONCLUSIONS: Most patients do not report significant changes in their tinnitus status after surgery. Tinnitus evolution is unpredictable and not related to the type of surgical approach. Thus, tinnitus should not be used as a criterion for selecting the surgical approach. Tinnitus worsening appears to influence QOL following surgery for VS.

Evaluation of a commercial double-recognition ELISA for caprine tuberculosis diagnosis: Sensitivity, specificity, and correlation to macroscopic and microscopic lesions.

Ante-mortem diagnosis of caprine tuberculosis, as in other ruminant species, is a complex process. Therefore, it is sometimes necessary to apply a combination of methods that increases the sensitivity of diagnosis while maintaining adequate specificity. In the present study, we analysed the use of ELISA based on a double-recognition methodology for the diagnosis of goat tuberculosis. Serum samples from animals with tuberculosis, confirmed by histopathological studies and presence of Ziehl-Neelsen-positive bacteria in the lesions, were used to assess sensitivity. Sera from flocks without tuberculosis were used to assess diagnostic specificity. The relationship between ELISA results and the type of tuberculous lesions, both macroscopic and microscopic, was analysed. The sensitivity and specificity of ELISA test were 69.9% and 97.9%, respectively. Sensitivity was higher in animals with macroscopic lesions, indicating more advanced forms of the disease. Similarly, a higher sensitivity was found in animals with microscopic lesions associated with active tuberculosis, such as cavitary lesions.

[Quantitative analysis of COVID-19 and its psychological and educational impacts on university and secondary students in Córdoba, Spain]. / Análisis cuantitativo del COVID-19 y sus impactos psicológicos y educativos en estudiantes universitarios y de secundaria en Córdoba, España.

INTRODUCCION: The COVID-19 pandemic that began in Wuhan, China, at the end of 2019, and which today threatens all the inhabitants of the planet, is currently the priority research topic. In this context, this article focuses on how this health problem directly affects the psychological and educational status of 344 university and high school students in Córdoba, Spain. MATERIAL AND METHODS: For the analysis, the structural equation model (SEM) has been used, through the quantification of a set of relationships between one or more independent variables, trying to condense the pandemic scenario and its health, psychological and educational implications. RESULTS: The first latent variable "Health" is causal of the latent variable "Psychology", and, of the endogenous variables, "social relations effects", "sadness effects" and "sexuality effects", which confirms that the COVID-19 seriously affected the psychological behavior of university and high school students in Córdoba.

Identification of novel genomic regions associated with resistance to Pyrenophora tritici-repentis races 1 and 5 in spring wheat landraces using association analysis.

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease of wheat worldwide. Host plant resistance is the best strategy to manage this disease. Traditionally, bi-parental mapping populations have been used to identify and map quantitative trait loci (QTL) affecting tan spot resistance in wheat. The association mapping (AM) could be an alternative approach to identify QTL based on linkage disequilibrium (LD) within a diverse germplasm set. In this study, we assessed resistance to P. tritici-repentis races 1 and 5 in 567 spring wheat landraces from the USDA-ARS National Small Grains Collection (NSGC). Using 832 diversity array technology (DArT) markers, QTL for resistance to P. tritici-repentis races 1 and 5 were identified. A linear model with principal components suggests that at least seven and three DArT markers were significantly associated with resistance to P. tritici-repentis races 1 and 5, respectively. The DArT markers associated with resistance to race 1 were detected on chromosomes 1D, 2A, 2B, 2D, 4A, 5B, and 7D and explained 1.3-3.1% of the phenotypic variance, while markers associated with resistance to race 5 were distributed on 2D, 6A and 7D, and explained 2.2-5.9% of the phenotypic variance. Some of the genomic regions identified in this study correspond to previously identified loci responsible for resistance to P. tritici-repentis, offering validation for our AM approach. Other regions identified were novel and could possess genes useful for resistance breeding. Some DArT markers associated with resistance to race 1 also were localized in the same regions of wheat chromosomes where QTL for resistance to yellow rust, leaf rust and powdery mildew, have been mapped previously. This study demonstrates that AM can be a useful approach to identify and map novel genomic regions involved in resistance to P. tritici-repentis.

Prediction of osteoporotic hip fracture in postmenopausal women through patient-specific FE analyses and machine learning.

A great challenge in osteoporosis clinical assessment is identifying patients at higher risk of hip fracture. Bone Mineral Density (BMD) measured by Dual-Energy X-Ray Absorptiometry (DXA) is the current gold-standard, but its classification accuracy is limited to 65%. DXA-based Finite Element (FE) models have been developed to predict the mechanical failure of the bone. Yet, their contribution has been modest. In this study, supervised machine learning (ML) is applied in conjunction with clinical and computationally driven mechanical attributes. Through this multi-technique approach, we aimed to obtain a predictive model that outperforms BMD and other clinical data alone, as well as to identify the best-learned ML classifier within a group of suitable algorithms. A total number of 137 postmenopausal women (81.4 ± 6.95 years) were included in the study and separated into a fracture group (n = 89) and a control group (n = 48). A semi-automatic and patient-specific DXA-based FE model was used to generate mechanical attributes, describing the geometry, the impact force, bone structure and mechanical response of the bone after a sideways-fall. After preprocessing the whole dataset, 19 attributes were selected as predictors. Support Vector Machine (SVM) with radial basis function (RBF), Logistic Regression, Shallow Neural Networks and Random Forest were tested through a comprehensive validation procedure to compare their predictive performance. Clinical attributes were used alone in another experimental setup for the sake of comparison. SVM was confirmed to generate the best-learned algorithm for both experimental setups, including 19 attributes and only clinical attributes. The first, generated the best-learned model and outperformed BMD by 14pp. The results suggests that this approach could be easily integrated for effective prediction of hip fracture without interrupting the actual clinical workflow.

Chlamydophila abortus infection in the mouse: a useful model of the ovine disease.

Chlamydophila (C.) abortus is an obligate intracellular bacterium able to colonize the placenta of several species of mammals, which may induce abortion in the last third of pregnancy. The infection affects mainly small ruminants resulting in major economic losses in farming industries worldwide. Furthermore, its zoonotic risk has been reported in pregnant farmers or abattoir workers. Mouse models have been widely used to study both the pathology of the disease and the role of immune cells in controlling infection. Moreover, this animal experimental model has been considered a useful tool to evaluate new vaccine candidates and adjuvants that could prevent abortion and reduce fetal death. Future studies using these models will provide and reveal information about the precise mechanisms in the immune response against C. abortus and will increase the knowledge about poorly understood issues such as chlamydial persistence.

Effect of progesterone on the vaccination and immune response against Chlamydia abortus in sheep.

Chlamydia abortus produces ovine enzootic abortion (OEA). Symptoms are not observed until the organism colonises the placenta, eventually causing abortion. Infected animals become carriers and will shed the organism in the following oestruses. This process suggests that sex hormones might play an important role in the physiopathology of OEA, affecting the success of chlamydial clearance and also jeopardising the effectiveness of vaccination. However, the mechanisms through which sex hormones are involved in chlamydial pathogenicity remain unclear. The aim of this study, therefore, was to determine the effect of progesterone on the immune response against C. abortus and on the protection conferred by an experimental inactivated vaccine in sheep. Eighteen sheep were ovariectomised and divided into four groups: vaccinated and progesterone-treated (V-PG), vaccinated and non-treated (V-NT), non-vaccinated and non-treated (NV-NT) and non-vaccinated and progesterone-treated sheep (NV-PG). Animals from both PG groups were treated with commercial medroxyprogesterone acetate impregnated intravaginal sponges before and during the vaccination (V-PG) or just before challenge (NV-PG). The animals from both V groups were subcutaneously immunised with an experimental inactivated vaccine, which was seen to confer high protection in previous studies. All sheep were challenged intratracheally with C. abortus strain AB7 and were sacrificed on day 8 post-infection. Morbidity was measured as the variation in rectal temperature and samples of sera were collected for antibody and cytokine (IFN-γ and IL-10) analysis by commercial ELISA. In addition, lung and lymph node samples were collected for chlamydial detection by qPCR and for histopathological and immunohistochemical analyses. Sheep from the V-PG group showed less severe or no lesions and lower morbidity than the other groups. They also had the highest abundance of regulatory T-cells. The sheep from V-NT also manifested high antibody levels against C. abortus and less severe lesions than those observed in non-vaccinated sheep, which showed high morbidity, low antibody levels and severe lesions, especially in NV-NT. These results confirm the effectiveness of the experimental vaccine employed and suggest that progesterone could enhance the effect.

Men suffer vertebral fractures with similar spinal T-scores to women.

OBJECTIVE: To evaluate the applicability of the WHO densitometric criteria for the diagnosis of spinal osteoporosis in men and to compare it with women with vertebral fractures, as well as to analyze the role of vertebral dimensions in the development of spinal fractures. METHODS: For these purposes we analyzed, using DXA, vertebral projected area and lumbar bone mineral density (BMD), as well as T and Z-scores in lumbar spine in a cohort of 66946 individuals; 2556 of these subjects had one or more atraumatic vertebral fracture (396 men and 2160 postmenopausal women). RESULTS: Men and women with fractures showed significantly lower mean BMD, T-score and Z-score values than individuals without fractures while vertebral dimensions were similar in both groups of patients. When comparing men and women with vertebral fractures, the former showed a significantly greater projected area (46.89+/-5.5 vs. 39.13+/-4.6 cm(2) p<0.001) and lumbar BMD (0.991+/- 0.21 vs. 0.938+/- t0.19 g/cm(2) p<0.001). However, the median lumbar T-score values were similar for both sexes (-2.3 in women vs. -2.2 in men; p: NS). In addition, a similar percentage of men and women with vertebral fractures showed T-score values <-2.5 in the lumbar spine (44% vs. 46%, p=NS). CONCLUSION: We conclude that although men with vertebral fractures have greater vertebral dimensions and BMD than women, the lumbar T-scores are similar. Therefore, it seems reasonable to adopt the same T-score values for the diagnosis of osteoporosis in men and women.

A novel DXA-based hip failure index captures hip fragility independent of BMD.

Capability of a novel dual-energy X-ray absorptiometry (DXA)-based hip failure index (HiFI) to discriminate between hip fracture cases and controls was evaluated. Given the constraints of planar DXA, the femoral neck was assumed a foam-filled ( approximately trabecular bone), thin-walled ( approximately cortical bone) sandwich structure, while HiFI estimated the critical force sufficient to buckle the wall of such a structure. Proximal femur DXA data from 1379 women aged 65yr and older, 268 with prior hip fracture were used. Comparison between standard areal bone mineral density (BMD), femur strength index (FSI), and HiFI was based on areas under receiver operatoring characteristic curves (AUC). The mean femoral neck BMD (SD) was 0.689 (0.109) g/cm(2) among the cases and 0.768 (0.119) g/cm(2) among the controls; the mean FSI 1.33 (0.36) and 1.54 (0.41), and the mean HiFI -0.28 (0.14) and -0.18 (0.15), respectively; all intergroup differences were highly significant (p<0.001). The intergroup difference for HiFI remained significant (p<0.002) after adjusting for age and BMD or FSI. The AUCs were 0.696 (95% confidence interval [CI]: 0.661-0.730) for BMD, 0.665 (0.630-0.700) for FSI, and 0.701 (0.666-0.736) for HiFI. In conclusion, HiFI may capture structural traits that account for femoral neck fragility independently of BMD or FSI. Obviously, the use of actual geometric and structural information from three-dimensional imaging of the femoral neck would help diminish the crude assumptions of the present DXA approach and reveal the true potential of the HiFI approach to gauge hip fragility and identify at-risk individuals for hip fractures.