Ebola virus VP35 interacts non-covalently with ubiquitin chains to promote viral replication.

Ebolavirus (EBOV) belongs to a family of highly pathogenic viruses that cause severe hemorrhagic fever in humans. EBOV replication requires the activity of the viral polymerase complex, which includes the cofactor and Interferon antagonist VP35. We previously showed that the covalent ubiquitination of VP35 promotes virus replication by regulating interactions with the polymerase complex. In addition, VP35 can also interact non-covalently with ubiquitin (Ub); however, the function of this interaction is unknown. Here, we report that VP35 interacts with free (unanchored) K63-linked polyUb chains. Ectopic expression of Isopeptidase T (USP5), which is known to degrade unanchored polyUb chains, reduced VP35 association with Ub and correlated with diminished polymerase activity in a minigenome assay. Using computational methods, we modeled the VP35-Ub non-covalent interacting complex, identified the VP35-Ub interacting surface, and tested mutations to validate the interface. Docking simulations identified chemical compounds that can block VP35-Ub interactions leading to reduced viral polymerase activity. Treatment with the compounds reduced replication of infectious EBOV in cells and in vivo in a mouse model. In conclusion, we identified a novel role of unanchored polyUb in regulating Ebola virus polymerase function and discovered compounds that have promising anti-Ebola virus activity.

Ebola Virus VP35 Interacts Non-Covalently with Ubiquitin Chains to Promote Viral Replication Creating New Therapeutic Opportunities.

Ebolavirus (EBOV) belongs to a family of highly pathogenic viruses that cause severe hemorrhagic fever in humans. EBOV replication requires the activity of the viral polymerase complex, which includes the co-factor and Interferon antagonist VP35. We previously showed that the covalent ubiquitination of VP35 promotes virus replication by regulating interactions with the polymerase complex. In addition, VP35 can also interact non-covalently with ubiquitin (Ub); however, the function of this interaction is unknown. Here, we report that VP35 interacts with free (unanchored) K63-linked polyUb chains. Ectopic expression of Isopeptidase T (USP5), which is known to degrade unanchored polyUb chains, reduced VP35 association with Ub and correlated with diminished polymerase activity in a minigenome assay. Using computational methods, we modeled the VP35-Ub non-covalent interacting complex, identified the VP35-Ub interacting surface and tested mutations to validate the interface. Docking simulations identified chemical compounds that can block VP35-Ub interactions leading to reduced viral polymerase activity that correlated with reduced replication of infectious EBOV. In conclusion, we identified a novel role of unanchored polyUb in regulating Ebola virus polymerase function and discovered compounds that have promising anti-Ebola virus activity.

Assessment of the moisturizing properties of a magnetic mask containing iron oxide particles.

BACKGROUND: Moisturizer is an important component of many cosmetic products. It helps to maintain the skin's integrity and its barrier functions. Recently, magnetic masks that seek to improve the properties of the skin have been developed and have become a new cosmetic trend. However, scientific proof of their stated properties is lacking. AIMS: To test whether iron oxide contained in a face mask with magnetic properties in an oily matrix with a freeze-dried aloe-vera base increases moisturization of the skin and improves skin barrier function. METHODS: Formulations were prepared containing an oil phase (67.3% wt.) and a solid phase (32.7% wt.). The moisturizing properties of the mask were tested by measuring in vivo electrochemical impedance spectroscopy, contact angle, and visual appearance. Meanwhile, human panel tests were performed to evaluate the sensory perception of potential users. RESULTS: The moisturizing effect of the iron oxide mask is clearly superior to that of the other tested samples. Water retention and low transepidermal water loss (TEWL) were evidenced for the iron oxide magnetic mask. Its occlusive action on the skin resulted in larger water contact angles and enhances the barrier effect. A favorable sensory perception on the part of the users was obtained for the iron oxide magnetic mask. CONCLUSION: The presence of iron oxide and the magnetic property of the mask enhance occlusive behavior, diminishing the TEWL. Sensory analysis of the iron oxide magnetic mask performed by human panel tests shows that they possess characteristics including neutral odor, and easy, pleasant-feeling application.

[Theoretical evaluation of optimal and suboptimal antiretroviral therapy strategies for HIV infection]. / Evaluación teórica de estrategias óptimas y sub-óptimas de terapia antirretroviral para el control de la infección por VIH.

HIV interaction with the immune response is modeled mathematically. Initially, a detailed model is proposed that consists of a system of differential equations including immune cells (antigen presenting cells, T latent infected cells, T actively infected cells, resting T cells, helper T cells, inactive cytotoxic cells and active cytotoxic cells) and viral particles. Then, stability conditions are given from the basic reproduction number and numerical simulations are performed. From this it is possible to conclude what are the most influential parameters to reduce infection. From the initial model, a control problem is formulated in order to determine the most appropriate type of intervention to ensure high levels of activated T cells and immune response. Five different control strategies based on antiretroviral are evaluated to conclude that a strategy of constant control, obtained as the average value of optimal control, provides satisfactory results.

Se modela matemáticamente la interacción del VIH con la respuesta inmune. Inicialmente se construye un modelo de manera detallada, que consiste en un sistema de ecuaciones diferenciales que incluye células del sistema inmune (células presentadoras de antígenos, células T infectadas en estado de latencia, células T infectadas activadas, células T en reposo, células T colaboradoras, células de respuesta citotóxica inactivas y células de respuesta citotóxica activas) y partículas virales. A continuación se dan condiciones de estabilidad a partir del número básico de reproducción y se hacen simulaciones numéricas que permiten concluir cuáles son los parámetros más influyentes si se desea reducir la infección. A partir del modelo inicial, se formula un Problema de Control con el objetivo de determinar el tipo de intervención más apropiado que asegure niveles altos de células T activas y de respuesta inmune. Se evalúan entonces cinco estrategias de control diferentes basadas en antirretrovirales y se concluye que una estrategia de control constante, obtenida como el valor promedio del control óptimo, brinda resultados satisfactorios.

Evaluación teórica de estrategias óptimas y sub-óptimas de terapia antirretroviral para el control de la infección por VIH / Theoretical evaluation of optimal and suboptimal antiretroviral therapy strategies for HIV infection

RESUMEN Se modela matemáticamente la interacción del VIH con la respuesta inmune. Inicialmente se construye un modelo de manera detallada, que consiste en un sistema de ecuaciones diferenciales que incluye células del sistema inmune (células presentadoras de antígenos, células T infectadas en estado de latencia, células T infectadas activadas, células T en reposo, células T colaboradoras, células de respuesta citotóxica inactivas y células de respuesta citotóxica activas) y partículas virales. A continuación se dan condiciones de estabilidad a partir del número básico de reproducción y se hacen simulaciones numéricas que permiten concluir cuáles son los parámetros más influyentes si se desea reducir la infección. A partir del modelo inicial, se formula un Problema de Control con el objetivo de determinar el tipo de intervención más apropiado que asegure niveles altos de células T activas y de respuesta inmune. Se evalúan entonces cinco estrategias de control diferentes basadas en antirretrovirales y se concluye que una estrategia de control constante, obtenida como el valor promedio del control óptimo, brinda resultados satisfactorios.(AU)

ABSTRACT HIV interaction with the immune response is modeled mathematically. Initially, a detailed model is proposed that consists of a system of differential equations including immune cells (antigen presenting cells, T latent infected cells, T actively infected cells, resting T cells, helper T cells, inactive cytotoxic cells and active cytotoxic cells) and viral particles. Then, stability conditions are given from the basic reproduction number and numerical simulations are performed. From this it is possible to conclude what are the most influential parameters to reduce infection. From the initial model, a control problem is formulated in order to determine the most appropriate type of intervention to ensure high levels of activated T cells and immune response. Five different control strategies based on antiretroviral are evaluated to conclude that a strategy of constant control, obtained as the average value of optimal control, provides satisfactory results.(AU)

Ranolazine for stable angina pectoris.

BACKGROUND: Stable angina pectoris is a chronic medical condition with significant impact on mortality and quality of life; it can be macrovascular or microvascular in origin. Ranolazine is a second-line anti-anginal drug approved for use in people with stable angina. However, the effects of ranolazine for people with angina are considered to be modest, with uncertain clinical relevance. OBJECTIVES: To assess the effects of ranolazine on cardiovascular and non-cardiovascular mortality, all-cause mortality, quality of life, acute myocardial infarction incidence, angina episodes frequency and adverse events incidence in stable angina patients, used either as monotherapy or as add-on therapy, and compared to placebo or any other anti-anginal agent. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase and the Conference Proceedings Citation Index - Science in February 2016, as well as regional databases and trials registers. We also screened reference lists. SELECTION CRITERIA: Randomised controlled trials (RCTs) which directly compared the effects of ranolazine versus placebo or other anti-anginals in people with stable angina pectoris were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies, extracted data and assessed risk of bias. Estimates of treatment effects were calculated using risk ratios (RR), mean differences (MD) and standardised mean differences (SMD) with 95% confidence intervals (CI) using a fixed-effect model. Where we found statistically significant heterogeneity (Chi² P < 0.10), we used a random-effects model for pooling estimates. Meta-analysis was not performed where we found considerable heterogeneity (I² ≥ 75%). We used GRADE criteria to assess evidence quality and the GRADE profiler (GRADEpro GDT) to import data from Review Manager 5.3 to create 'Summary of findings' tables. MAIN RESULTS: We included 17 RCTs (9975 participants, mean age 63.3 years). We found very limited (or no) data to inform most planned comparisons. Summary data were used to inform comparison of ranolazine versus placebo. Overall, risk of bias was assessed as unclear.For add-on ranolazine compared to placebo, no data were available to estimate cardiovascular and non-cardiovascular mortality. We found uncertainty about the effect of ranolazine on: all-cause mortality (1000 mg twice daily, RR 0.83, 95% CI 0.26 to 2.71; 3 studies, 2053 participants; low quality evidence); quality of life (any dose, SMD 0.25, 95% CI -0.01 to 0.52; 4 studies, 1563 participants; I² = 73%; moderate quality evidence); and incidence of non-fatal acute myocardial infarction (AMI) (1000mg twice daily, RR 0.40, 95% CI 0.08 to 2.07; 2 studies, 1509 participants; low quality evidence). Add-on ranolazine 1000 mg twice daily reduced the fervour of angina episodes (MD -0.66, 95% CI -0.97 to -0.35; 3 studies, 2004 participants; I² = 39%; moderate quality evidence) but increased the risk of non-serious adverse events (RR 1.22, 95% CI 1.06 to 1.40; 3 studies, 2053 participants; moderate quality evidence).For ranolazine as monotherapy compared to placebo, we found uncertain effect on cardiovascular mortality (1000 mg twice daily, RR 1.03, 95% CI 0.56 to 1.88; 1 study, 2604 participants; low quality evidence). No data were available to estimate non-cardiovascular mortality. We also found an uncertain effect on all-cause mortality for ranolazine (1000 mg twice daily, RR 1.00, 95% CI 0.81 to 1.25; 3 studies, 6249 participants; low quality evidence), quality of life (1000 mg twice daily, MD 0.28, 95% CI -1.57 to 2.13; 3 studies, 2254 participants; moderate quality evidence), non-fatal AMI incidence (any dose, RR 0.88, 95% CI 0.69 to 1.12; 3 studies, 2983 participants; I² = 50%; low quality evidence), and frequency of angina episodes (any dose, MD 0.08, 95% CI -0.85 to 1.01; 2 studies, 402 participants; low quality evidence). We found an increased risk for non-serious adverse events associated with ranolazine (any dose, RR 1.50, 95% CI 1.12 to 2.00; 3 studies, 947 participants; very low quality evidence). AUTHORS' CONCLUSIONS: We found very low quality evidence showing that people with stable angina who received ranolazine as monotherapy had increased risk of presenting non-serious adverse events compared to those given placebo. We found low quality evidence indicating that people with stable angina who received ranolazine showed uncertain effect on the risk of cardiovascular death (for ranolazine given as monotherapy), all-cause death and non-fatal AMI, and the frequency of angina episodes (for ranolazine given as monotherapy) compared to those given placebo. Moderate quality evidence indicated that people with stable angina who received ranolazine showed uncertain effect on quality of life compared with people who received placebo. Moderate quality evidence also indicated that people with stable angina who received ranolazine as add-on therapy had fewer angina episodes but increased risk of presenting non-serious adverse events compared to those given placebo.

Antifibrinolytic therapy to reduce haemoptysis from any cause.

BACKGROUND: Haemoptysis is a common pathology around the world, occurring with more frequency in low-income countries. It has different etiologies, many of which have infectious characteristics. Antifibrinolytic agents are commonly used to manage bleeding from different sources, but their usefulness in pulmonology is unclear. OBJECTIVES: To evaluate the effectiveness and safety of antifibrinolytic agents in reducing the volume and duration of haemoptysis in adult and paediatric patients. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library, EMBASE and LILACS for publications that describe randomized controlled trials (RCTs) of antifibrinolytic therapy in patients presenting with haemoptysis. We also performed an independent search in MEDLINE for relevant trials not yet included in CENTRAL or DARE. Searches are up to date to the 19th September 2016. We conducted electronic and manual searches of relevant national and international journals. We reviewed the reference lists of included studies to locate relevant randomized controlled trials (RCTs). An additional search was carried out to find unpublished RCTs. SELECTION CRITERIA: We included RCTs designed to evaluate the effectiveness and safety of antifibrinolytic agents in reducing haemoptysis in adult and paediatric patients of both genders presenting with haemoptysis of any etiology and severity. The intervention of interest was the administration of antifibrinolytic agents compared with placebo or no treatment. DATA COLLECTION AND ANALYSIS: All reviewers independently assessed methodological quality and extracted data tables pre-designed for this review. MAIN RESULTS: The electronic literature search identified 1 original study that met the eligibility criteria. One unpublished study was also identified through manual searches. Therefore two randomized controlled trials met the inclusion criteria: Tscheikuna 2002 (via electronic searches) and Ruiz 1994 (via manual searches). Tscheikuna 2002, a double-blind RCT performed in Thailand, evaluated the effectiveness of tranexamic acid (TXA, an antifibrinolytic agent) administered orally in 46 hospital in- and outpatients with haemoptysis of various etiologies. Ruiz 1994, a double-blind RCT performed in Peru, evaluated the effectiveness of intravenous TXA in 24 hospitalised patients presenting with haemoptysis secondary to tuberculosis.Pooled together, results demonstrated a significant reduction in bleeding time between patients receiving TXA and patients receiving placebo with a weighted mean difference (WMD) of -19.47 (95% CI -26.90 to -12.03 hours), but with high heterogeneity (I² = 52%). TXA did not affect remission of haemoptysis evaluated at seven days after the start of treatment. Adverse effects caused by the drug's mechanism of action were not reported. There was no significant difference in the incidence of mild side effects between active and placebo groups (OR 3.13, 95% CI 0.80 to 12.24). AUTHORS' CONCLUSIONS: There is insufficient evidence to judge whether antifibrinolytics should be used to treat haemoptysis from any cause, though limited evidence suggests they may reduce the duration of bleeding.

[A simulation model for HIV infection and its interaction with a cytotoxicimmune response]. / Modelo de simulación para la infección por VIH y su interacción con la respuesta inmune citotóxica.

Nonlinear differential equations were used for formulating a mathematical model describing the dynamics of HIV interaction with CD4 T-cells which are considered to be activated or not activated during recognition of viral particles; in either case they are susceptible to HIV infection. The system's equilibrium points were found and local stability was determined for trivial equilibrium or the absence of infection based on the basic reproduction number. The model was used for numerical simulation to show infected cell and viral load patterns regarding the variations of some parameters. The model was then reformulated, considering a cytotoxic cellular immune response and numerical simulation was run again.

Direct thrombin inhibitors versus vitamin K antagonists for preventing cerebral or systemic embolism in people with non-valvular atrial fibrillation.

BACKGROUND: Chronic anticoagulation with vitamin K antagonists (VKAs) prevents ischaemic stroke and systemic embolism in people with non-valvular atrial fibrillation (AF) but dose adjustment, coagulation monitoring and bleeding limits its use. Direct thrombin inhibitors (DTIs) are under investigation as potential alternatives. OBJECTIVES: To assess (1) the comparative efficacy of long-term anticoagulation using DTIs versus VKAs on vascular deaths and ischaemic events in people with non-valvular AF, and (2) the comparative safety of chronic anticoagulation using DTIs versus VKAs on (a) fatal and non-fatal major bleeding events including haemorrhagic strokes, (b) adverse events other than bleeding and ischaemic events that lead to treatment discontinuation and (c) all-cause mortality in people with non-valvular AF. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (July 2013), the Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library, May 2013), MEDLINE (1950 to July 2013), EMBASE (1980 to October 2013), LILACS (1982 to October 2013) and trials registers (September 2013). We also searched the websites of clinical trials and pharmaceutical companies and handsearched the reference lists of articles and conference proceedings. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing DTIs versus VKAs for prevention of stroke and systemic embolism in people with non-valvular AF. DATA COLLECTION AND ANALYSIS: All three review authors independently performed data extraction and assessment of risk of bias. Primary analyses compared all DTIs combined versus warfarin. We performed post hoc analyses excluding ximelagatran because this drug was withdrawn from the market owing to safety concerns. MAIN RESULTS: We included eight studies involving a total of 27,557 participants with non-valvular AF and one or more risk factors for stroke; 26,601 of them were assigned to standard doses groups and included in the primary analysis. The DTIs: dabigatran 110 mg twice daily and 150 mg twice daily (three studies, 12,355 participants), AZD0837 300 mg once per day (two studies, 233 participants) and ximelagatran 36 mg twice per day (three studies, 3726 participants) were compared with the VKA warfarin (10,287 participants). Overall risk of bias and statistical heterogeneity of the studies included were low.The odds of vascular death and ischaemic events were not significantly different between all DTIs and warfarin (odds ratio (OR) 0.94, 95% confidence interval (CI) 0.85 to 1.05). Sensitivity analysis by dose of dabigatran on reduction in ischaemic events and vascular mortality indicated that dabigatran 150 mg twice daily was superior to warfarin although the effect estimate was of borderline statistical significance (OR 0.86, 95% CI 0.75 to 0.99). Sensitivity analyses by other factors did not alter the results. Fatal and non-fatal major bleeding events, including haemorrhagic strokes, were less frequent with the DTIs (OR 0.87, 95% CI 0.78 to 0.97). Adverse events that led to discontinuation of treatment were significantly more frequent with the DTIs (OR 2.18, 95% CI 1.82 to 2.61). All-cause mortality was similar between DTIs and warfarin (OR 0.91, 95% CI 0.83 to 1.01). AUTHORS' CONCLUSIONS: DTIs were as efficacious as VKAs for the composite outcome of vascular death and ischaemic events and only the dose of dabigatran 150 mg twice daily was found to be superior to warfarin. DTIs were associated with fewer major haemorrhagic events, including haemorrhagic strokes. Adverse events that led to discontinuation of treatment occurred more frequently with the DTIs. We detected no difference in death from all causes.

Modelo de simulación para la infección por VIH y su interacción con la respuesta inmune citotóxica / A simulation model for HIV infection and its interaction with a cytotoxicimmune response

Con base en ecuaciones diferenciales no lineales se formula un modelo matemático que describe la dinámica de interacción del VIH con células T CD4, que se considera que pueden ser activadas o no activadas en el reconocimiento de partículas virales; en cualquiera de los dos casos, son susceptibles a la infección con el virus. Se encuentran los puntos de equilibrio del sistema y en el caso particular del equilibrio trivial o de ausencia de infección, se determina su estabilidad local con base en el número básico de reproducción. Se efectúa además la simulación numérica del modelo para establecer el comportamiento que presentan las células infectadas y la carga viral, frente a variaciones de algunos de los parámetros. Finalmente, se reformula el modelo considerando respuesta inmune celular de tipo citotóxico y se realiza la simulación numérica.

Nonlinear differential equations were used for formulating a mathematical model describing the dynamics of HIV interaction with CD4 T-cells which are considered to be activated or not activated during recognition of viral particles; in either case they are susceptible to HIV infection. The system's equilibrium points were found and local stability was determined for trivial equilibrium or the absence of infection based on the basic reproduction number. The model was used for numerical simulation to show infected cell and viral load patterns regarding the variations of some parameters. The model was then reformulated, considering a cytotoxic cellular immune response and numerical simulation was run again.

[Mathematical modelling of an infectious disease in a prison setting and optimal preventative control strategies]. / Modelado matemático de una enfermedad infecciosa en un centro de reclusión y estrategias óptimas de control preventivo.

A mathematical model was constructed for modelling transmission dynamics and the evolution of an infectious disease in a prison setting, considering asymptomatic infectious people, symptomatic infectious people and isolated infectious people. The model was proposed as a nonlinear differential equation system for describing disease epidemiology. The model's stability was analysed for including a preventative control strategy which would enable finding a suitable basic reproduction number-based control protocol. A cost function related to the system of differential equations was formulated to minimise infectious populations and intervention costs; such function was minimised by using the Pontryagin maximum principle which determines optimum preventative control strategies by minimising both infectious populations and associated costs. A numerical analysis of the model was made, considering preventative control effectiveness levels and different control weighting constants. Conclusions were drawn. The basic reproduction number characterises system stability and leads to determining clear control criteria; a preventative control threshold was defined, based on the controlled basic reproduction number which enabled deducing that disease control requires uniform preventative control involving high rates of effectiveness.

Antifibrinolytic therapy to reduce haemoptysis from any cause.

BACKGROUND: Haemoptysis is a common pathology around the world, occurring with more frequency in low-income countries. It has different etiologies, many of which have infectious characteristics. Antifibrinolytic agents are commonly used to manage bleeding from different sources, but their usefulness in pulmonology is unclear. OBJECTIVES: To evaluate the effectiveness and safety of antifibrinolytic agents in reducing the volume and duration of haemoptysis in adult and paediatric patients. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library, EMBASE and LILACS for publications that describe randomized controlled trials (RCTs) of antifibrinolytic therapy in patients presenting with haemoptysis. We also performed an independent search in MEDLINE for relevant trials not yet included in CENTRAL or DARE.We conducted electronic and manual searches of relevant national and international journals.We reviewed the reference lists of included studies to locate relevant randomized controlled trials (RCTs). An additional search was carried out to find unpublished RCTs. SELECTION CRITERIA: We included RCTs designed to evaluate the effectiveness and safety of antifibrinolytic agents in reducing haemoptysis in adult and paediatric patients of both genders presenting with haemoptysis of any etiology and severity. The intervention of interest was the administration of antifibrinolytic agents compared with placebo or no treatment. DATA COLLECTION AND ANALYSIS: All reviewers independently assessed methodological quality and extracted data tables pre-designed for this review. MAIN RESULTS: We found two randomized controlled trials which met the inclusion criteria: Tscheikuna 2002 (via electronic searches) and Ruiz 1994 (via manual searches). We did not exclude any of the relevant studies we found.Tscheikuna 2002, a double-blind RCT performed in Thailand, evaluated the effectiveness of tranexamic acid (TXA, an antifibrinolytic agent) administered orally in 46 hospital in- and outpatients with haemoptysis of various etiologies. Ruiz 1994, a double-blind RCT performed in Peru, evaluated the effectiveness of intravenous TXA in 24 hospitalised patients presenting with haemoptysis secondary to tuberculosis.Pooled together, results demonstrated a significant reduction in bleeding time between patients receiving TXA and patients receiving placebo with a weighted mean difference (WMD) of -19.47 (95% CI -26.90 to -12.03 hours), but with high heterogeneity (I² = 52%). TXA did not affect remission of haemoptysis evaluated at seven days after the start of treatment. Adverse effects caused by the drug's mechanism of action were not reported. There was no significant difference in the incidence of mild side effects between active and placebo groups (OR 3.13, 95% CI 0.80 to 12.24). AUTHORS' CONCLUSIONS: There is insufficient evidence to judge whether antifibrinolytics should be used to treat haemoptysis from any cause, though limited evidence suggests they may reduce the duration of bleeding.

Direct thrombin inhibitors versus vitamin K antagonists or low molecular weight heparins for prevention of venous thromboembolism following total hip or knee replacement.

BACKGROUND: Patients who have undergone total hip or knee replacement (THR, TKR) have a high risk of developing venous thromboembolism (VTE) following surgery, despite appropriate anticoagulation with warfarin or low molecular weight heparin (LMWH). New anticoagulants are under investigation. OBJECTIVES: To examine the efficacy and safety of prophylactic anticoagulation with direct thrombin inhibitors (DTIs) versus LMWH or vitamin K antagonists in the prevention of VTE in patients undergoing THR or TKR. SEARCH STRATEGY: The Cochrane Peripheral Vascular Disease Group searched their Specialized Register (last searched 12 March 2010) and CENTRAL (last searched 2010, Issue 2). SELECTION CRITERIA: Randomised controlled trials. DATA COLLECTION AND ANALYSIS: Three reviewers independently assessed methodological quality and extracted data in pre-designed tables. The reported follow-up events were included MAIN RESULTS: We included 14 studies included involving 21,642 patients evaluated for efficacy and 27,360 for safety. No difference was observed in major VTE in DTIs compared with LMWH in both types of operations (odds ratio (OR) 0.91; 95% confidence interval (CI) 0.69 to 1.19), with high heterogeneity (I(2) 71%). No difference was observed with warfarin (OR 0.85; 95% CI 0.63 to 1.15) in TKR, with no heterogeneity (I(2) 0%).More total bleeding events were observed in the DTI group (in ximelagatran and dabigatran but not in desirudin) in patients subjected to THR (OR 1.40; 95% CI 1.06, 1.85; I(2) 41%) compared with LMWH. No difference was observed with warfarin in TKR (OR 1.76; 95% CI 0.91 to 3.38; I(2) 0%). All-cause mortality was higher in the DTI group when the reported follow-up events were included (OR 2.06; 95% CI 1.10 to 3.87).Studies that initiated anticoagulation before surgery showed less VTE events; those that began anticoagulation after surgery showed more VTE events in comparison with LMWH. Therefore, the effect of the DTIs compared with LMWH appears to be influenced by the time of initiation of coagulation more than the effect of the drug itself.The results obtained from sensitivity analysis, did not differ from the analysed results; this strengthens the value of the results. AUTHORS' CONCLUSIONS: Direct thrombin inhibitors are as effective in the prevention of major venous thromboembolism in THR or TKR as LMWH and vitamin K antagonists. However, they show higher mortality and cause more bleeding than LMWH. No severe hepatic complications were reported in the analysed studies. Use of ximelagatran is not recommended for VTE prevention in patients who have undergone orthopedic surgery. More studies are necessary regarding dabigatran.

Human Lyme arthritis and the immunoglobulin G antibody response to the 37-kilodalton arthritis-related protein of Borrelia burgdorferi.

In Borrelia burgdorferi-infected C3H-scid mice, antiserum to a differentially expressed, 37-kDa spirochetal outer-surface protein, termed arthritis-related protein (Arp), has been shown to prevent or reduce the severity of arthritis. In this study, we determined the immunoglobulin G (IgG) antibody responses to this spirochetal protein in single serum samples from 124 antibiotic-treated human patients with early or late manifestations of Lyme disease and in serial serum samples from 20 historic, untreated patients who were followed longitudinally from early infection through the period of arthritis. These 20 patients were representative of the spectrum of the severity and duration of Lyme arthritis. Among the 124 antibiotic-treated patients, 53% with culture-proven erythema migrans (EM) had IgG responses to recombinant glutathione S-transferase (GST)-Arp, as did 59% of the patients with facial palsy and 68% of those with Lyme arthritis. In addition, 75 to 80% of the 20 past, untreated patients had reactivity with this protein when EM was present, during initial episodes of joint pain, or during the maximal period of arthritis. There was no association at any of these three time points between GST-Arp antibody levels and the severity of the maximal attack of arthritis or the total duration of arthritis. Thus, after the first several weeks of infection, 60 to 80% of patients had IgG antibody responses to GST-Arp, but this response did not correlate with the severity or duration of Lyme arthritis.