Guías Argentinas para el diagnóstico, la prevención y el tratamiento de la osteoporosis 2015

La osteoporosis es una enfermedad en constante crecimiento y que afecta a más de 200 millones de personas en todo el mundo. Nuestras recomendaciones son guías para el diagnóstico, la prevención y tratamiento, pero no normas para las decisiones clínicas en casos individuales. El médico debe adaptarlas a situaciones en la práctica clínica cotidiana, incorporando factores personales que trascienden los límites de estas guías y hacen al saber y al arte de la práctica médica. Como todo conocimiento científico, deben ser actualizadas periódicamente a medida que se adquieran nuevas, mejores y más efectivas herramientas diagnósticas y terapéuticas.Osteoporosis is an evolving disease which affects over 200 million people worldwide. Our recommendations are guidelines for its diagnosis, prevention and treatment, but they do not constitute standards for clinical decisions in individual cases. The physician must adapt them to individual special situations, incorporating personal factors that transcend the limits of these guidelines and are dependent on the knowledge and art of the practice of Medicine. These guidelines should be reviewed and updated periodically as new, better and more effective diagnostic and therapeutic tools become available

Distributed transactional reads: the strong, the quick, the fresh & the impossible

International audienceThis paper studies the costs and trade-offs of providing transactional consistent reads in a distributed storage system. We identify the following dimensions: read consistency, read delay (latency), and data freshness. We show that there is a three-way trade-off between them, which can be summarised as follows: (i) it is not possible to ensure at the same time order-preserving (e.g., causally-consistent) or atomic reads, Minimal Delay, and maximal freshness; thus, reading data that is the most fresh without delay is possible only in a weakly-isolated mode; (ii) to ensure atomic or order-preserving reads at Minimal Delay imposes to read data from the past (not fresh); (iii) however, order-preserving minimal-delay reads can be fresher than atomic; (iv) reading atomic or order-preserving data at maximal freshness may block reads or writes indefinitely. Our impossibility results hold independently of other features of the database, such as update semantics (totally ordered or not) or data model (structured or unstructured). Guided by these results, we modify an existing protocol to ensure minimal-delay reads (at the cost of freshness) under atomic-visibility and causally-consistent semantics. Our experimental evaluation supports the theoretical results

La diabetes altera el potencial osteogénico de células progenitoras de médula ósea: efectos del tratamiento con metformina

En este trabajo, estudiamos el efecto de una Diabetes inducida por destrucción parcial de la masa de células beta pancreáticas, sobre el compromiso osteogénico de células progenitoras de médula ósea (CPMO), y su modulación por el tratamiento oral con Metformina. Para ello utilizamos ratas Sprague Dawley, divididas en cuatro grupos: controles [C], controles tratadas con Metformina [M], diabéticas [D], y diabéticas tratadas con Metformina [DM]. La inducción de Diabetes se realizó, por inyección intraperitoneal sucesiva de ácido nicotínico y estreptozotocina. Sobre los cultivos de CPMO se evaluó la actividad específica de Fosfatasa Alcalina (FAL) y la producción de Colágeno tipo 1 (Col-1) en estado basal y en medio de diferenciación osteogénico luego de 15 días. A los 21 días, se evaluaron los depósitos de mineral extracelular. La FAL y el Col-1 de CPMO basales, no mostraron diferencias significativas entre los cuatro grupos experimentales. Al cabo de 15 días, las CPMO de ratas M mostraron un incremento en el Col-1 de 122 % respecto de C; D 30 % respecto de C y DM 68 % respecto de C. La FAL expresó un 171 % para M, 34 % para D; y 125 % para DM todos respecto de C. Luego de 21 días, se observó una disminución en la mineralización de las CPMO de D (65 % respecto del grupo C). El tratamiento con metformina incrementó la mineralización de las CPMO en todos los casos. En conclusión, en nuestro modelo experimental de Diabetes, ésta disminuye el potencial osteogénico de las CPMO, un efecto que es parcialmente revertido por el tratamiento oral con Metformina. Estos hallazgos podrían explicar, al menos en parte, las alteraciones óseas descriptas en el hueso asociadas con la Diabetes.Diabetes mellitus is associated with an increased incidence of skeletal abnormalities, resulting in lower bone formation and/or remodeling. Osteopenia, osteoporosis and an increased incidence of non-traumatic fractures has been particularly observed in patients with type 2 diabetes. Recently, we have demonstrated that metformin has in vitro and in vivo osteogenic effects: (a) it stimulates the proliferation, differentiation and mineralization of osteoblasts in culture, and (b) in non-diabetic rats, it increases the repair of minimal bone lesions and improves femoral trabecular bone microarchitecture. In this study, we evaluated in rats the effect of diabetes induction by a partial destruction of pancreatic beta cells, on the osteogenic commitment of bone marrow progenitor cells (BMPC), and the modulation of this effect by orally administered metformin. We used young male Sprague Dawley rats (200 g), divided into four groups: untreated non-diabetic controls [C], non-diabetic rats treated for 2 weeks with metformin administered in drinking water (100 mg/kg/day) [M], untreated diabetic rats [D], and diabetic rats treated for 2 weeks with metformin (100 mg/kg/day) [DM]. Induction of Diabetes was performed one week prior to treatment with metformin, by successive intraperitoneal injections with 75 mg/kg body weight of nicotinic acid and 60 mg/kg body weight of streptozotocin. At the end of all treatments, blood samples were obtained to confirm the development of Diabetes, after which the animals were sacrificed by cervical dislocation under anesthesia. Femora and/or tibiae were dissected, and bone marrow cells were collected by flushing the bone diaphysal canal with Dulbecco’s modified essential medium (DMEM) under sterile conditions. Adherent cells were grown to confluence in DMEM-10 % fetal bovine serum (FBS), after which we assessed alkaline phosphatase specific activity (ALP) by an enzymatic kinetic method, and type 1 collagen production (Col-1) by a Sirius Red colorimetric method (basal osteoblastic differentiation of BMPC). Subsequently, BMPC were submitted to an osteogenic induction for 15 days with an osteogenic medium (DMEM-10 % FBS containing ascorbic acid and sodium beta-glycerophosphate), after which ALP and Col-1 were evaluated. Basal ALP activity and type 1 collagen production (BMPC without osteogenic differentiation) showed no significant differences between the four experimental groups. After 15 days of culture in osteogenic medium, BMPC from control rats increased their expression of ALP (5 times compared to baseline) and collagen production (11 times compared to baseline). BMPC from diabetic rats after 15 days culture in osteogenic medium, also showed a significant (although smaller) increase in ALP (2-3 fold over basal activity) and collagen production (4-fold compared to baseline). BMPC obtained from rats treated with metformin (groups M and DM) and submitted to osteogenic induction for 15 days, showed an approximately 2-4-fold increase in both ALP and Col-1 (when compared with groups C and D, respectively). After 21 days of osteogenic induction, a decrease was observed in the mineralization of BMPC obtained from group D (65 % of that for group C). Treatment with metformin increased the mineralizing capacity of BMPC in all cases, including a reversal of the inhibitory effect of Diabetes on this parameter. In conclusion, we have found that our model of Diabetes reduces the osteogenic potential of bone marrow progenitor cells, and that this effect is partially reverted by orally administered metformin. These findings could explain, at least in part, the bone alterations that have been associated with Diabetes mellitus

Argentine guidelines for the diagnosis, prevention and treatment of osteoporosis, 2015

La osteoporosis es una enfermedad en constante crecimiento y que afecta a más de 200 millones de personas en todo el mundo. Nuestras recomendaciones son guías para el diagnóstico, la prevención y tratamiento, pero no normas para las decisiones clínicas en casos individuales. El médico debe adaptarlas a situaciones en la práctica clínica cotidiana, incorporando factores personales que trascienden los límites de estas guías y hacen al saber y al arte de la práctica médica. Como todo conocimiento científico, deben ser actualizadas periódicamente a medida que se adquieran nuevas, mejores y más efectivas herramientas diagnósticas y terapéuticas.Osteoporosis is an evolving disease which affects over 200 million people worldwide. Our recommendations are guidelines for its diagnosis, prevention and treatment, but they do not constitute standards for clinical decisions in individual cases. The physician must adapt them to individual special situations, incorporating personal factors that transcend the limits of these guidelines and are dependent on the knowledge and art of the practice of Medicine. These guidelines should be reviewed and updated periodically as new, better and more effective diagnostic and therapeutic tools become available.Laboratorio de Investigación en Osteopatías y Metabolismo Minera

Reliability, validity and psychometric properties of the Greek translation of the Major Depression Inventory

BACKGROUND: The Major Depression Inventory (MDI) is a brief self-rating scale for the assessment of depression. It is reported to be valid because it is based on the universe of symptoms of DSM-IV and ICD-10 depression. The aim of the current preliminary study was to assess the reliability, validity and psychometric properties of the Greek translation of the MDI. METHODS: 30 depressed patients of mean age 23.41 (± 5.77) years, and 68 controls patients of mean age 25.08 (± 11.42) years, entered the study. In 18 of them, the instrument was re-applied 1–2 days later and the Translation and Back Translation made. Clinical diagnosis was reached with the use of the SCAN v.2.0 and the International Personality Disorders Examination (IPDE). The Center for Epidemiological Studies-Depression (CES-D) and the Zung Depression Rating Scale (ZDRS) were applied for cross-validation purposes. Statistical analysis included ANOVA, the Spearman Product Moment Correlation Coefficient, Principal Components Analysis and the calculation of Cronbach's α. RESULTS: Sensitivity and specificity were 0.86 and 0.94, respectively, at 26/27. Cronbach's α for the total scale was equal to 0.89. The Spearman's rho between MDI and CES-D was 0.86 and between MDI and ZDRS was 0.76. The factor analysis revealed two factors but the first accounted for 54% of variance while the second only for 9%. The test-retest reliability was excellent (Spearman's rho between 0.53 and 0.96 for individual items and 0.89 for total score). CONCLUSION: The current study provided preliminary evidence concerning the reliability and validity of the Greek translation of the MDI. Its properties are similar to those reported in the international literature, but further research is necessary

Natural disturbance impacts on trade-offs and co-benefits of forest biodiversity and carbon

With accelerating environmental change, understanding forest disturbance impacts on trade-offs between biodiversity and carbon dynamics is of high socio-economic importance. Most studies, however, have assessed immediate or short-term effects of disturbance, while long-term impacts remain poorly understood. Using a tree-ring-based approach, we analysed the effect of 250 years of disturbances on present-day biodiversity indicators and carbon dynamics in primary forests. Disturbance legacies spanning centuries shaped contemporary forest co-benefits and trade-offs, with contrasting, local-scale effects. Disturbances enhanced carbon sequestration, reaching maximum rates within a comparatively narrow post-disturbance window (up to 50 years). Concurrently, disturbance diminished aboveground carbon storage, which gradually returned to peak levels over centuries. Temporal patterns in biodiversity potential were bimodal; the first maximum coincided with the short-term post-disturbance carbon sequestration peak, and the second occurred during periods of maximum carbon storage in complex old-growth forest. Despite fluctuating local-scale trade-offs, forest biodiversity and carbon storage remained stable across the broader study region, and our data support a positive relationship between carbon stocks and biodiversity potential. These findings underscore the interdependencies of forest processes, and highlight the necessity of large-scale conservation programmes to effectively promote both biodiversity and long-term carbon storage, particularly given the accelerating global biodiversity and climate crises

Development of a validated patient-reported symptom metric for pediatric Eosinophilic Esophagitis: qualitative methods

<p>Abstract</p> <p>Background</p> <p>Previous attempts to measure symptoms in pediatric Eosinophilic Esophagitis (EoE) have not fully included patients and parents in the item development process. We sought to identify and validate key patient self-reported and parent proxy-reported outcomes (PROs) specific to EoE.</p> <p>Methods</p> <p>We developed methodology for focus and cognitive interviews based on the Food and Drug Administration (FDA) guidelines for PROs, the validated generic PedsQL™ guidelines, and the consolidated criteria for reporting qualitative research (COREQ). Both child (ages 8-12 and 13-18) and parent-proxy (ages 2-4, 5-7, 8-12, and 13-18) interviews were conducted.</p> <p>Results</p> <p>We conducted 75 interviews to construct the new instrument. Items were identified and developed from individual focus interviews, followed by cognitive interviews for face and content validation. Initial domains of symptom frequency and severity were developed, and open-ended questions were used to generate specific items during the focus interviews. Once developed, the instrument construct, instructions, timeframe, scoring, and specific items were systematically reviewed with a separate group of patients and their parents during the cognitive interviews.</p> <p>Conclusions</p> <p>To capture the full impact of pediatric EoE, both histologic findings and PROs need to be included as equally important outcome measures. We have developed the face and content validated Pediatric Eosinophilic Esophagitis Symptom Score (PEESS™ v2.0). The PEESS™ v2.0 metric is now undergoing multisite national field testing as the next iterative instrument development phase.</p

Bone Mass and Strength in Older Men With Type 2 Diabetes: The Osteoporotic Fractures in Men Study

The effects of type 2 diabetes mellitus (T2DM) on bone volumetric density, bone geometry, and estimates of bone strength are not well established. We used peripheral quantitative computed tomography (pQCT) to compare tibial and radial bone volumetric density (vBMD, mg/cm3), total (ToA, mm2) and cortical (CoA, mm2) bone area and estimates of bone compressive and bending strength in a subset (n = 1171) of men (≥65 years of age) who participated in the multisite Osteoporotic Fractures in Men (MrOS) study. Analysis of covariance–adjusted bone data for clinic site, age, and limb length (model 1) and further adjusted for body weight (model 2) were used to compare data between participants with (n = 190) and without (n = 981) T2DM. At both the distal tibia and radius, patients with T2DM had greater bone vBMD (+2% to +4%, model 1, p < .05) and a smaller bone area (ToA −1% to −4%, model 2, p < .05). The higher vBMD compensated for lower bone area, resulting in no differences in estimated compressive bone strength at the distal trabecular bone regions. At the mostly cortical bone midshaft sites of the radius and tibia, men with T2DM had lower ToA (−1% to −3%, p < .05), resulting in lower bone bending strength at both sites after adjusting for body weight (−2% to −5%, p < .05) despite the lack of difference in cortical vBMD at these sites. These data demonstrate that older men with T2DM have bone strength that is low relative to body weight at the cortical-rich midshaft of the radius despite no difference in cortical vBMD. © 2010 American Society for Bone and Mineral Researc

Local spatial structure of forest biomass and its consequences for remote sensing of carbon stocks

Advances in forest carbon mapping have the potential to greatly reduce uncertainties in the global carbon budget and to facilitate effective emissions mitigation strategies such as REDD+. Though broad scale mapping is based primarily on remote sensing data, the accuracy of resulting forest carbon stock estimates depends critically on the quality of field measurements and calibration procedures. The mismatch in spatial scales between field inventory plots and larger pixels of current and planned remote sensing products for forest biomass mapping is of particular concern, as it has the potential to introduce errors, especially if forest biomass shows strong local spatial variation. Here, we used 30 large (8–50 ha) globally distributed permanent forest plots to quantify the spatial variability in aboveground biomass (AGB) at spatial grains ranging from 5 to 250m (0.025–6.25 ha), and we evaluate the implications of this variability for calibrating remote sensing products using simulated remote sensing footprints. We found that the spatial sampling error in AGB is large for standard plot sizes, averaging 46.3% for 0.1 ha subplots and 16.6% for 1 ha subplots. Topographically heterogeneous sites showed positive spatial autocorrelation in AGB at scales of 100m and above; at smaller scales, most study sites showed negative or nonexistent spatial autocorrelation in AGB. We further show that when field calibration plots are smaller than the remote sensing pixels, the high local spatial variability in AGB leads to a substantial “dilution” bias in calibration parameters, a bias that cannot be removed with current statistical methods. Overall, our results suggest that topography should be explicitly accounted for in future sampling strategies and that much care must be taken in designing calibration schemes if remote sensing of forest carbon is to achieve its promise