Milk production and efficiency of utilization of nitrogen, metabolizable protein, and amino acids are affected by protein and energy supplies in dairy cows fed alfalfa-based diets.

Alfalfa has a lower fiber digestibility and a greater concentration of degradable protein than grasses. Dairy cows could benefit from an increased digestibility of alfalfa fibers, or from a better match between nitrogen and energy supplies in the rumen. Alfalfa cultivars with improved fiber digestibility represent an opportunity to increase milk production, but no independent studies have tested these cultivars under the agroclimatic conditions of Canada. Moreover, decreasing metabolizable protein (MP) supply could increase N use efficiency while decreasing environmental impact, but it is often associated with a decrease in milk protein yield, possibly caused by a reduced supply of essential AA. This study evaluated the performance of dairy cows fed diets based on a regular or a reduced-lignin alfalfa cultivar and measured the effect of energy levels at low MP supply when digestible His (dHis), Lys (dLys), and Met (dMet) requirements were met. Eight Holstein cows were used in a double 4 × 4 Latin square design, each square representing an alfalfa cultivar. Within each square, 4 diets were tested: the control diet was formulated for an adequate supply of MP and energy (AMP_AE), whereas the 3 other diets were formulated to be deficient in MP (DMP; formulated to meet 90% of the MP requirement) with deficient (94% of requirement: DMP_DE), adequate (99% of requirement: DMP_AE), or excess energy supply (104% of requirement; DMP_EE). Alfalfa cultivars had no significant effect on all measured parameters. As compared with cows receiving AMP_AE, the dry matter intake of cows fed DMP_AE and DMP_EE was not significantly different but decreased for cows fed DMP_DE. The AMP_AE diet provided 103% of MP and 108% of NEL requirements whereas DMP_DE, DMP_AE, and DMP_EE diets provided 84, 87, and 87% of MP and 94, 101, and 107% of NEL requirements, respectively. In contrast to design, feeding DMP_EE resulted in a similar energy supply compared with AMP_AE, although MP supply has been effectively reduced. This resulted in a maintained milk and milk component yields and improved the efficiency of utilization of N, MP, and essential AA. The DMP diets decreased total N excretion, whereas DMP_AE and DMP_EE diets also decreased milk urea-N concentration. Reducing MP supply without negative effects on dairy cow performance is possible when energy, dHis, dLys, and dMet requirements are met. This could reduce N excretion and decrease the environmental impact of milk production.

[Complications of lymph node dissection in thyroid cancer]. / Komplikationen der Lymphknotendissektion beim Schilddrüsenkarzinom.

Cervical lymphadenectomy in thyroid cancer is a frequent intervention with around 20,000 operations per year in Germany. Some of the complications are identical with those in thyroid surgery, such as recurrent laryngeal nerve palsy and hypoparathyroidism as well as postoperative bleeding and wound infection. Specific complications of lateral lymphadenectomy are lesions of the accessory, phrenic and hypoglossal nerves, the sympathetic trunk and cervical plexus as well as lesions of the salivary glands and lymphatic vessels, in particular the thoracic duct. Most of these complications are rare with a frequency of less than 1%. Profound knowledge of the anatomy and a meticulous dissection technique make a decisive contribution to minimizing these complications.

Evidence-based Canadian guidelines for tele-retina screening for diabetic retinopathy: recommendations from the Canadian Retina Research Network (CR2N) Tele-Retina Steering Committee.

OBJECTIVE: The purpose of this report is to develop a consensus for Canadian national guidelines specific to a tele-medicine approach to screening for diabetic retinopathy (DR) using evidence-based and clinical data. METHODS: Canadian Tele-Screening Grading Scales for DR and diabetic macular edema (DME) were created primarily based on severity grading scales outlined by the International Clinical Diabetic Retinopathy Disease Severity Scale (ICDR) and the Scottish DR Grading Scheme 2007. Other grading scales used in international screening programs and the clinical expertise of the Canadian Retina Research Network members and retina specialists nationwide were also used in the creation of the guidelines. RESULTS: National Tele-Screening Guidelines for DR and DME with and without optical coherence tomography (OCT) images are proposed. These outline a diagnosis and management algorithm for patients presenting with different stages of DR and/or DME. General guidelines detailing the requirements for imaged retina fields, image quality, quality control, and follow-up care and the role of visual acuity, pupil dilation, OCT, ultra-wide-field imaging, and artificial intelligence are discussed. CONCLUSIONS: Tele-retina screening can help to address the need for timely and effective screening for DR, whose prevalence continues to rise. A standardized and evidence-based national approach to DR tele-screening has been proposed, based on DR/DME grading using two 45° image fields or a single widefield or ultra-wide-field image, preferable use of OCT imaging, and a focus on local quality control measures.

Effects of sporidesmin on cultured biliary tract cells from Romney lambs that differed in their sensitivity to sporidesmin.

AIMS To investigate the effects of sporidesmin on cells cultured from the epithelial surface of sheep gallbladder walls, and to examine cellular responses to sporidesmin using cultures prepared from the gallbladders of sheep from selection lines that differed in sensitivity to sporidesmin-induced liver damage. METHODS Gallbladders were obtained following slaughter of lambs that were selected for resistance or susceptibility to sporidesmin-induced liver damage, or were not selected (controls). Monolayer cell cultures were established after incubation of excised gallbladders with protease to detach the lining epithelial cells from the muscular and connective tissue of the gallbladder wall. Released cells were harvested and transferred to culture flasks or dishes, then incubated with 1 µg/mL sporidesmin and were examined at 5 minute intervals, up to 3 hours, using light microscopy to monitor loss of attachment of cultured cells. Immunofluorescence staining of cell cultures was used to identify cytokeratin 19 as a marker for biliary epithelial cells, and to characterise sporidesmin-induced change in the cellular distribution of actin microfilaments. Gallbladder size was also measured. RESULTS In cultures incubated with sporidesmin, cells at the margins of sheets of cells showed the first signs of change, becoming unanchored from the culture vessels while remaining attached to the cell mass. This was followed by progressive detachment of sheets of cells and clumps of rounded cells. Disruption of cytoplasmic actin microfilaments with accumulation of actin in the cytoplasm adjacent to the plasma membrane preceded major detachment of cells. Cells from susceptible line lambs were extensively rounded up within 1 hour with complete or almost complete detachment within 2 hours, whereas cultures from resistant line lambs generally only contained detaching rounded-up cells at the periphery of monolayers within 2 hours; detachment observed in cells from the control line lambs was intermediate. There was a trend for gallbladders to be smaller in male lambs from the resistant line compared to the control or susceptible lines. CONCLUSIONS Altered cell adhesion and disruption of microfilament actin in biliary cell cultures incubated with sporidesmin suggest that biliary tract pathology may be due to the effects of the toxin on cytoplasmic and cell surface protein networks that affect the integrity of the epithelial lining of the biliary tract. These effects can be interpreted in terms of the hepatobiliary pathology of facial eczema, including potential differences in sensitivity of biliary tract cells that may contribute to inherited resistance and susceptibility to sporidesmin and hence facial eczema.

The effect of substrate rearing on growth, aerobic scope and physiology of larval white sturgeon Acipenser transmontanus.

The effect of substratum on growth and metabolic rate was assessed in larval white sturgeon Acipenser transmontanus. Yolk-sac larvae (YSL) were reared in bare tanks or tanks with gravel as substratum from hatch until approximately 16 days post hatch (dph). The effect of an artificial substratum was also evaluated on growth alone. Substratum had a significant effect on mass, with larvae reared in gravel and artificial substrata being larger than those reared without substratum. Routine metabolic rates were significantly lower and relative aerobic scope (the difference between maximum and routine metabolic rate) was significantly higher for YSL and feeding larvae (FL) reared in gravel relative to those reared in bare tanks, particularly before fish started feeding exogenously. Furthermore, gravel-reared larvae had higher whole-body glycogen concentrations relative to bare-tank-reared larvae. Routine factorial scope (maximum metabolic rate divided by routine metabolic rate) was relatively low in all treatments (< 1·7) indicating a limited ability to elevate metabolic rate above routine early in development and mass exponents for metabolic rate exceeded 1. Taken together, these data indicate that YSL reared without substratum may divert more of their energy to non-growth related processes impairing growth. This finding underscores the importance of adequate rearing substratum for growth of A. transmontanus and may provide support for habitat restoration and alternative hatchery rearing methods associated with sturgeon conservation.

Genetically tailored magnetosomes used as MRI probe for molecular imaging of brain tumor.

We investigate here the potential of single step production of genetically engineered magnetosomes, bacterial biogenic iron-oxide nanoparticles embedded in a lipid vesicle, as a new tailorable magnetic resonance molecular imaging probe. We demonstrate in vitro the specific binding and the significant internalization into U87 cells of magnetosomes decorated with RGD peptide. After injection at the tail vein of glioblastoma-bearing mice, we evidence in the first 2 h the rapid accumulation of both unlabeled and functionalized magnetosomes inside the tumor by Enhanced Permeability and Retention effects. 24 h after the injection, a specific enhancement of the tumor contrast is observed on MR images only for RGD-labeled magnetosomes. Post mortem acquisition of histological data confirms MRI results with more magnetosomes found into the tumor treated with functionalized magnetosomes. This work establishes the first proof-of-concept of a successful bio-integrated production of molecular imaging probe for MRI.

Optimization of pegylated iron oxide nanoplatforms for antibody coupling and bio-targeting.

PEGylation has been established as a valuable strategy to minimize nanoparticle clearance by the reticulo-endothelial system due to hydrophilicity and steric repulsion of PEG chains. In this study we functionalized superparamagnetic iron oxide nanoparticle surface with two PEG differing in their length (n = 23 and 44) and terminal functionality, COOH and CH3. By varying the ratio of the two different PEG, we optimized the molecular architecture of the nanoplatform to obtain maximum stability and low toxicity under physiological conditions. The best nanoplatform was evaluated as MRI contrast for mouse brain vascularization imaging at 7 T. The carboxylic acid functions of the nanoplatform were used to covalently bind an antibody, Ab. This antibody, labeled with a fluorophore, targets the ETA receptor, a G-protein-coupled receptor involved in the endothelin axis and overexpressed in various solid tumours, including ovarian, prostate, colon, breast, bladder and lung cancers. In vitro studies, performed by flow cytometry and magnetic quantification, showed the targeting efficiency of the Ab-nanoplatforms. Clearly, an imaging tracer for cancer diagnosis from a bimodal contrast agent (fluorescence and MRI) was thus obtained.

Model-Based Network Meta-Analysis: A Framework for Evidence Synthesis of Clinical Trial Data.

Model-based meta-analysis (MBMA) is increasingly used in drug development to inform decision-making and future trial designs, through the use of complex dose and/or time course models. Network meta-analysis (NMA) is increasingly being used by reimbursement agencies to estimate a set of coherent relative treatment effects for multiple treatments that respect the randomization within the trials. However, NMAs typically either consider different doses completely independently or lump them together, with few examples of models for dose. We propose a framework, model-based network meta-analysis (MBNMA), that combines both approaches, that respects randomization, and allows estimation and prediction for multiple agents and a range of doses, using plausible physiological dose-response models. We illustrate our approach with an example comparing the efficacies of triptans for migraine relief. This uses a binary endpoint, although we note that the model can be easily modified for other outcome types.

The Many Flavors of Model-Based Meta-Analysis: Part I-Introduction and Landmark Data.

Meta-analysis is an increasingly important aspect of drug development as companies look to benchmark their own compounds with the competition. There is scope to carry out a wide range of analyses addressing key research questions from preclinical through to postregistration. This set of tutorials will take the reader through key model-based meta-analysis (MBMA) methods with this first installment providing a general introduction before concentrating on classical and Bayesian methods for landmark data.

A case series of third-trimester raltegravir initiation: Impact on maternal HIV-1 viral load and obstetrical outcomes.

OBJECTIVE: To describe the impact of initiating raltegravir (RAL)-containing combination antiretroviral therapy (cART) regimens on HIV viral load (VL) in pregnant women who have high or suboptimal VL suppression late in pregnancy. METHODS: HIV-infected pregnant women who started RAL-containing cART after 28 weeks' gestation from 2007 to 2013 were identified in two university hospital centres. RESULTS AND DISCUSSION: Eleven HIV-infected women started RAL at a median gestational age of 35.7 weeks (range 31.1 to 38.0 weeks). Indications for RAL initiation were late presentation in pregnancy (n=4) and suboptimal VL suppression secondary to poor adherence or viral resistance (n=7). Mean VL at the time of RAL initiation was 73,959 copies/mL (range <40 to 523,975 copies/mL). Patients received RAL for a median of 20 days (range one to 71 days). The mean decline in VL from the time of RAL initiation to delivery was 1.93 log, excluding one patient who received only one RAL dose and one patient with undetectable VL at the time of RAL initiation. After eight days on RAL, 50% of the women achieved a VL <1000 copies/mL (the threshold for recommended Caesarean section to reduce the risk for perinatal transmission). There were no cases of perinatal HIV transmission. CONCLUSION: The present study provides preliminary data to support the use of RAL-containing cART to expedite HIV-1 VL reduction in women who have a high VL or suboptimal VL suppression late in pregnancy, and to decrease the risk of HIV perinatal transmission while avoiding Caesarean section. Further assessment of RAL safety during pregnancy is warranted.

OBJECTIF: Décrire les répercussions de l'amorce d'une antirétrovirothérapie prophylactique associative (ARPA) contenant du raltégravir (RAL) sur la charge virale (CV) du VIH chez les femmes enceintes dont la suppression de la CV est élevée ou sous-optimale en fin de grossesse. MÉTHODOLOGIE: Les chercheurs ont extrait le dossier des femmes enceintes infectées par le VIH qui avaient amorcé une ARAP contenant du RAL après 28 semaines de grossesse dans deux centres hospitaliers universitaires entre 2007 et 2013. RÉSULTATS ET EXPOSÉ: Onze femmes infectées ont entrepris un traitement de RAL à une médiane de 35,7 semaines de grossesse (plage de 31,1 à 38,0 semaines). Les indications pour entreprendre le RAL étaient une présentation tardive au suivi de grossesse (n=4) et une suppression sous-optimale de la CV en raison d'un mauvais respect du traitement ou d'une résistance virale (n=7). La CV moyenne au début du traitement au RAL était de 73 959 copies/mL (plage de moins de 40 copies/mL à 523 975 copies/mL). Les patientes ont pris du RAL pendant une médiane de 20 jours (plage de un à 71 jours). La diminution moyenne de la CV entre le début du RAL et l'accouchement était de 1,93 log, à l'exception d'une patiente qui n'a reçu qu'une dose de RAL et d'une patiente dont la CV n'était pas décelable au moment d'entreprendre le RAL. Au bout de huit jours de RAL, 50 % des femmes présentaient une CV inférieure à 1 000 copies/mL (le seuil pour recommander une césarienne afin de réduire le risque de transmission périnatale). Il n'y a d'ailleurs eu aucun cas de transmission périnatale du VIH. CONCLUSION: La présente étude fournit des données provisoires pour soutenir l'utilisation d'ARPA contenant du RAL afin d'accélérer la réduction de la CV du VIH-1 chez les femmes qui présentaient une CV élevée ou une suppression sous-optimale de leur CV pendant la grossesse, ainsi que pour réduire le risque de transmission périnatale du VIH tout en évitant une césarienne. Une évaluation plus approfondie de l'innocuité du RAL est justifiée pendant la grossesse.

Sildenafil for the Treatment of Pulmonary Arterial Hypertension in Infants with Bronchopulmonary Dysplasia.

Sildenafil, a phosphodiesterase-5 inhibitor, is a controversial treatment option for pulmonary arterial hypertension (PAH), a significant complication of bronchopulmonary dysplasia (BPD). The objective of this study was to evaluate the use of sildenafil in infants with PAH secondary to BPD. This was a retrospective review of medical records of all premature infants with PAH associated with BPD treated with sildenafil between January 2009 and May 2013 in a level 3 neonatal intensive care unit. The primary outcomes were clinical response (20 % decreases in respiratory support score or oxygen requirements) and echocardiographic response (20 % decrease in tricuspid regurgitation gradient or change of at least 1° of septal flattening). Twenty-three infants were included in the study. Significant echocardiographic and clinical responses were, respectively, observed in 71 and 35 % of cases. Most clinical responses were observed in the first 48 h of treatment, and the median time to an echocardiographic response was of 19 days. The median dose of sildenafil used was 4.4 mg/kg/day, with a median time to reach the maximum dose of 9 days. Transient hypotension was the primary reported side effect, and it was observed in 44 % of our study population. Sildenafil treatment in patients with PAH secondary to BPD was associated with an echocardiographic improvement in the majority of patients, whereas clinical improvement was observed in a minority of patients. Many infants presented with transient hypotension during the course of the treatment. Further prospective studies are required to better assess safety and efficacy of this treatment in this population.

Endothelin B receptors targeted by iron oxide nanoparticles functionalized with a specific antibody: toward immunoimaging of brain tumors.

In this study, we developed a new bimodal imaging tracer directed against endothelin B receptors to detect brain cancer cells using MRI and to assist tumor surgery with fluorescence imaging. This was achieved by coating the surface of iron oxide nanoparticles with a monoclonal antibody, rendomab-B1, labeled with a fluorescent dye. Two nanoplatforms were elaborated differing by the average number of antibodies grafted onto the nanoparticle surface. The targeting efficiency of these nanoplatforms was validated in vitro. Contrasting MRI properties were highlighted in vivo, demonstrating nanoparticle circulation in the brain through the vasculature.

[Intraoperative avoidance and recognition of recurrent laryngeal nerve palsy in thyroid surgery]. / Intraoperative Vermeidung und Erkennung von Rekurrensparesen in der Schilddrüsenchirurgie.

Recurrent laryngeal nerve palsy is an intrinsic complication of thyroid surgery. Prevention of nerve palsy is considered to be a feature of quality in this very frequently performed operation. Risk factors and prevention strategies are demonstrated and discussed with reference to the current literature. Exact knowledge of the anatomy and possible variants of the track of the recurrent laryngeal nerve as well as its visualization and careful dissection are the cornerstones for nerve preservation. The use of intraoperative neuromonitoring allows preservation of the anatomical structure and functional integrity of the nerve and lesions which are not visible can be detected. Preconditions for correct interpretation are a standardized application and preoperative and postoperative laryngoscopy.

[Intraoperative complications of neck surgery]. / Intraoperative Komplikationen bei Operationen im Halsbereich.

Intraoperative complications of neck surgery are uncommon and rarely life-threatening and exact anatomical knowledge and precise dissection are most important for prevention. Anatomical variants (e.g. non-recurrent nerve, extralaryngeal branching) predispose to damage of the recurrent laryngeal nerve. The use of intraoperative neuromonitoring (IONM) can prevent bilateral nerve damage but in cases of accidental nerve damage primary reconstruction can improve vocal cord function. Autotransplantation of parathyroid tissue can reduce the rate of hypoparathyroidism but cannot be postulated as a routine measure. Intraoperative bleeding can usually be well controlled and greater danger for the patient emanates from early postoperative bleeding for which many techniques (clip, ligature, vessel sealing) can be employed for prevention. Lesions of the thoracic duct can be controlled by clip, ligation or stitch. Smaller lesions of the trachea and esophagus can be secured with direct suture or muscle flap plasty. In cases of larger lesions plastic reconstruction or organ replacement can be necessary.

Investigation into the relationship between the gravity vector and the flow vector to improve performance in two-phase continuous flow biodiesel reactor.

The following study analyzes the performance of a continuous flow biodiesel reactor/separator. The reactor achieves high conversion of vegetable oil triglycerides to biodiesel while simultaneously separating co-product glycerol. The influence of the flow direction, relative to the gravity vector, on the reactor performance was measured. Reactor performance was assessed by both the conversion of vegetable oil triglycerides to biodiesel and the separation efficiency of removing the co-product glycerol. At slightly elevated temperatures of 40-50 degrees C, an overall feed of 1.2 L/min, a 6:1 M ratio of methanol to vegetable oil triglycerides, and a 1-1.3 wt.% potassium hydroxide catalyst loading, the reactor converted more than 96% of the pretreated waste vegetable oil to biodiesel. The reactor also separated 36-95% of the glycerol that was produced. Tilting the reactor away from the vertical direction produced a large increase in glycerol separation efficiency and only a small decrease in conversion.

Targeting Notch signaling in pancreatic cancer patients--rationale for new therapy.

Pancreatic cancer is one of the most aggressive and devastating human malignancies. Despite new knowledge in the molecular profile of pancreatic cancer and its precursor lesions, survival rates have changed very little over the last 40 years. Therefore, a better understanding of the detailed mechanisms underlying the pathogenesis of this disease is critical if we expect to develop new and effective strategies for prevention, early diagnosis and treatment of pancreatic cancer. The review herein focuses on a distinctive signaling pathway, the Notch pathway, which has recently been associated with carcinogenesis, including pancreatic cancer. It is aimed at summarizing key results which support a role for this pathway in the initiation, progression and maintenance of pancreatic cancer as a rationale for targeting and inhibiting this pathway in pancreatic cancer patients.

Behavioural signs of depression and apoptosis in the limbic system following myocardial infarction: effects of sertraline.

Depression is diagnosed in 15-30% of patients following myocardial infarction (MI) and this may also be observed in the rat. We measured the effects of the antidepressant sertraline on behavioural and biochemical events following MI in a rat model. Following surgery, MI rats and sham controls were treated with sertraline (10 mg/kg, i.p.) or saline. Subgroups of rats were tested for behavioural depression 14 days after surgery. Apoptosis was estimated in other rats by measuring caspase-3 activity and TUNEL positive cells (3 days after surgery) in limbic structures (amygdale, hippocampus, hypothalamus, frontal and prefrontal cortices). Bax/Bcl-2 ratio was measured 14 days after surgery. Behavioural signs of depression (decreased sucrose intake and forced swimming time) were found in saline-treated MI rats but not in sertraline-treated rats. Compared with controls, caspase-3 activity and TUNEL positive cells were significantly increased in most limbic structures of MI rats. High prefrontal Bax/Bcl-2 ratio in MI rats correlated with low forced swimming time. Apoptosis was not found in sertraline-treated MI rats. These results establish the bases of a rat model of depression following MI and show for the first time that a selective serotonin reuptake inhibitor prevents both behavioural and biochemical markers in this model.

Alendronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

BACKGROUND: Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Alendronate belongs to the bisphosphonate class of drugs, which act to inhibit bone resorption by interfering with the activity of osteoclasts. OBJECTIVES: To assess the efficacy of alendronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women. SEARCH STRATEGY: We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007. SELECTION CRITERIA: Women receiving at least one year of alendronate, for postmenopausal osteoporosis, were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence. DATA COLLECTION AND ANALYSIS: We undertook study selection and data abstraction in duplicate. We performed meta-analysis of fracture outcomes using relative risks and a > 15% relative change was considered clinically important. We assessed study quality through reporting of allocation concealment, blinding and withdrawals. MAIN RESULTS: Eleven trials representing 12,068 women were included in the review. Relative (RRR) and absolute (ARR) risk reductions for the 10 mg dose were as follows. For vertebral fractures, a significant 45% RRR was found (RR 0.55, 95% CI 0.45 to 0.67). This was significant for both primary prevention, with 45% RRR (RR 0.55, 95% CI 0.38 to 0.80) and 2% ARR, and secondary prevention with 45% RRR (RR 0.55, 95% CI 0.43 to 0.69) and 6% ARR. For non-vertebral fractures, a significant 16% RRR was found (RR 0.84, 95% CI 0.74 to 0.94). This was significant for secondary prevention, with 23% RRR (RR 0.77, 95% CI 0.64 to 0.92) and 2% ARR, but not for primary prevention (RR 0.89, 95% CI 0.76 to 1.04). There was a significant 40% RRR in hip fractures (RR 0.60, 95% CI 0.40 to 0.92), but only secondary prevention was significant with 53% RRR (RR 0.47, 95% CI 0.26 to 0.85) and 1% ARR. The only significance found for wrist was in secondary prevention, with a 50% RRR (RR 0.50 95% CI 0.34 to 0.73) and 2% ARR. For adverse events, we found no statistically significant differences in any included study. However, observational data raise concerns regarding potential risk for upper gastrointestinal injury and, less commonly, osteonecrosis of the jaw. AUTHORS' CONCLUSIONS: At 10 mg per day, both clinically important and statistically significant reductions in vertebral, non-vertebral, hip and wrist fractures were observed for secondary prevention ('gold' level evidence, www.cochranemsk.org). We found no statistically significant results for primary prevention, with the exception of vertebral fractures, for which the reduction was clinically important ('gold' level evidence).

Etidronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

BACKGROUND: Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Etidronate belongs to the bisphosphonate class of drugs which act to inhibit bone resorption by interfering with the activity of osteoclasts. OBJECTIVES: To assess the efficacy of etidronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women. SEARCH STRATEGY: We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007. SELECTION CRITERIA: Women receiving at least one year of etidronate for postmenopausal osteoporosis were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence. DATA COLLECTION AND ANALYSIS: Study selection and data abstraction was done in duplicate. Meta-analysis of fracture outcomes was performed with data presented as relative risks and a relative change greater than 15% was considered clinically important. Study quality was assessed through the reporting of allocation concealment, blinding and withdrawals. MAIN RESULTS: Eleven studies representing a total of 1248 patients were included in the review.A significant 41% relative risk reduction (RRR) in vertebral fractures across eight studies (RR 0.59, 95% CI 0.36 to 0.96) was found. The six secondary prevention trials demonstrated a significant RRR of 47% in vertebral fractures (RR 0.53, 95% CI 0.32 to 0.87) and a 5% absolute risk reduction (ARR); compared with the pooled result for the two primary prevention trials (RR 3.03, 95% CI 0.32 to 28.44), which was not significant. There were no statistically significant risk reductions for non-vertebral (RR 0.98, 95% CI 0.68 to 1.42), hip (RR 1.20, 95% CI 0.37 to 3.88) or wrist fractures (RR 0.87, 95% CI: 0.32 to 2.36). For adverse events, no statistically significant differences were found in the included studies. However, observational data has led to concerns regarding potential risk for upper gastrointestinal injury. AUTHORS' CONCLUSIONS: Etidronate, at 400 mg per day, demonstrated a statistically significant and clinically important benefit in the secondary prevention of vertebral fractures. No statistically significant reductions in vertebral fractures were observed when it was used for primary prevention. In addition, no statistically significant reductions in non-vertebral, hip, or wrist fractures were found, regardless of whether etidronate was used for primary or secondary prevention. The level of evidence for all outcomes is Silver (www.cochranemsk.org.).

Risedronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

BACKGROUND: Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Risedronate belongs to the bisphosphonate class of drugs which act to inhibit bone resorption by interfering with the activity of osteoclasts. OBJECTIVES: To assess the efficacy of residronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women. SEARCH STRATEGY: We searched CENTRAL, MEDLINE and EMBASE. Relevant randomized controlled trials published between 1966 to 2007 were identified. SELECTION CRITERIA: Women receiving at least one year of risedronate for postmenopausal osteoporosis were compared to those receiving placebo or concurrent calcium/vitamin D or both. The outcome was fracture incidence. DATA COLLECTION AND ANALYSIS: We carried out study selection and data abstraction in duplicate. Study quality was assessed through the reporting of allocation concealment, blinding and withdrawals. Meta-analysis was preformed using relative risks and a >15% relative change was considered clinically important. MAIN RESULTS: Seven trials were included in the review representing 14,049 women. Relative (RRR) and absolute (ARR) risk reductions for the 5 mg dose were as follows. Risk estimates for primary prevention were available only for vertebral and non vertebral fractures and showed no statistically significant effect of risedronate on fractures. For secondary prevention, a significant 39% RRR in vertebral fractures (RR 0.61, 95% CI 0.50 to 0.76) with 5% ARR was found. For non-vertebral fractures, a significant 20% RRR (RR 0.80, 95% CI 0.72 to 0.90) with 2% ARR and for hip fractures there was a significant 26% RRR (RR: 0.74, 95% CI 0.59 to 0.94) with a 1% ARR. When primary and secondary prevention studies were combined, the reduction in fractures remained statistically significant for both vertebral (RR 0.63, 0.51 to 0.77) and non vertebral fractures (RR 0.80, 0.72 to 0.90)For adverse events, no statistically significant differences were found in any of the included studies. However, observational data has led to concerns regarding the potential risk for upper gastrointestinal injury and, less commonly, osteonecrosis of the jaw. AUTHORS' CONCLUSIONS: At 5 mg/day a statistically significant and clinically important benefit in the secondary prevention of vertebral, non-vertebral and hip fractures was observed, but not for wrist. The level of evidence for secondary prevention is Gold (www.cochranemsk.org) for vertebral and non-vertebral and Silver for hip and wrist. There were no statistically significant reductions in the primary prevention of vertebral and non-vertebral fractures. The level of evidence is Silver.