Inflammatory Cytokines Can Induce Synthesis Of Type-I Interferon

Type I interferon (IFN) is induced in virus infected cells, secreted and it inhibits viral replication in neighboring cells. IFN is also an important player in many non-viral diseases and in the development of normal immune cells. Although the signaling pathways for IFN induction by viral RNA or DNA have been extensively studied, its mode of induction in uninfected cells remains obscure. Here, we report that inflammatory cytokines, such as TNF-α and IL-1β, can induce IFN-β through activation of the cytoplasmic RIG-I signaling pathway. However, RIG-I is activated not by RNA, but by PACT, the protein activator of PKR. In cell lines or primary cells expressing RIG-I and PACT, activation of the MAPK, p38, by cytokine signaling, leads to phosphorylation of PACT, which binds to primed RIG-I and activates its signaling pathway. Thus, a new mode of type I IFN induction by ubiquitous inflammatory cytokines has been revealed.

Key points

Cytochalasin D followed by TNF-α / IL-1β treatment activates IFN-β expression.IFN-β expression happens due to activation of RIG-I signaling.Interaction between RIG-I and PACT activates IFN-β expression.

Cell-type-specific need of Ddx3 and PACT for interferon induction by RNA viruses

IMPORTANCE

Interferon-stimulated genes (ISGs) are induced in response to interferon expression due to viral infections. Role of these ISGs can be variable in different cells or organs. Our study highlights such cell-specific role of an ISG, Ddx3, which regulates the translation of mRNAs essential for interferon induction (PACT) and interferon signaling (STAT1) in a cell-specific manner. Our study also highlights the role of PACT in RNA virus-induced RLR signaling. Our study depicts how Ddx3 regulates innate immune signaling pathways in an indirect manner. Such cell-specific behavior of ISGs helps us to better understand viral pathogenesis and highlights the complexities of viral tropism and innate immune responses.

Herpes simplex virus 1 evades cellular antiviral response by inducing microRNA-24, which attenuates STING synthesis

STING is a nodal point for cellular innate immune response to microbial infections, autoimmunity and cancer; it triggers the synthesis of the antiviral proteins, type I interferons. Many DNA viruses, including Herpes Simplex Virus 1 (HSV1), trigger STING signaling causing inhibition of virus replication. Here, we report that HSV1 evades this antiviral immune response by inducing a cellular microRNA, miR-24, which binds to the 3’ untranslated region of STING mRNA and inhibits its translation. Expression of the gene encoding miR-24 is induced by the transcription factor AP1 and activated by MAP kinases in HSV1-infected cells. Introduction of exogenous miR-24 or prior activation of MAPKs, causes further enhancement of HSV1 replication in STING-expressing cells. Conversely, transfection of antimiR-24 inhibits virus replication in those cells. HSV1 infection of mice causes neuropathy and death; using two routes of infection, we demonstrated that intracranial injection of antimiR-24 alleviates both morbidity and mortality of the infected mice. Our studies reveal a new immune evasion strategy adopted by HSV1 through the regulation of STING and demonstrates that it can be exploited to enhance STING’s antiviral action.

The type I interferon system is the first line of cellular antiviral innate immune response. Virus infection is recognized by various pattern recognition receptors in the infected cell and it activates the interferon system to inhibit virus replication. However, viruses have evolved various mechanisms to evade the cellular immune response and enhance viral replication. Our study uncovers an immune evasion strategy used by the Herpes Simplex virus to circumvent the cGAS/STING signaling pathway which is the pivotal innate immune response to combat DNA virus replication. miR-24 induction by HSV1 targets STING and hence, dampens Type I Immune response against the virus. The induction of miR-24 is regulated by virus induced MAPK activation, which are also required during early lytic cycles of HSV1 replication and is indispensable for HSV1 reactivation from latency in neurons; depicting a new direct co-relation between MAPK activation and HSV1 replication orchestrated through cellular miR-24. Silencing of miR-24 in mice brain curtails viral replication and disease severity. Overall, these results indicate possible therapeutic use of stable antimiR-24 against HSV1 and other diseases that are alleviated by STING.

[Peripheral truncal blocks-Overview and assessment]

By implementation of sonography for regional anesthesia, truncal blocks became more relevant in the daily practice of anesthesia and pain therapy. Due to visualized needle guidance ultrasound supports more safety and helps to avoid complications during needle placement. Additionally, complex punctures are possible that were associated with higher risk using landmarks alone. Next to the blocking of specific nerve structures, interfascial and compartment blocks have also become established, whereby the visualization of individual nerves and plexus structures is not of relevance. The present review article describes published and clinically established puncture techniques with respect to the indications and procedures. The clinical value is reported according to the scientific evidence and the analgesic profile. Moreover, the authors explain potential risks, complications and dosing of local anesthetic agents.

Uncertainties and characteristic limits of counting and spectrometric dosimetry systems

In the event of a radiological emergency, early and reliable knowledge of radioactivity concentrations is important information for organising countermeasures to protect the general public and emergency workers. This is ensured by all European countries in operating airborne radioactivity and dose rate early warning networks. To increase the provided information, the development of new secondary standards based on scintillation detectors for the measurement of ambient dose rate equivalent was initiated in 2014. This paper shows the state-of-the-art of uncertainties and characteristic limits of low dose rate measurement that can be achieved by scintillation-based detector (CeBr₃) and gas-based detectors (a high-pressure ionization chamber, HPIC). The comparison of the devices shows the performance and the metrological potential of the CeBr₃ detector: Its uncertainty is already very close to the uncertainty of reference values. Looking at the question how to select a reference instrument, the CeBr₃ detector with a special data evaluation is even superior to the HPIC and qualifies therefore as a modern secondary standard: Providing both, dose rate and nuclide information.

Regulatory role of Ifit2 in mouse hepatitis virus induced neuroinflammation

Interferons (IFNs) are known to protect from virus dissemination and pathogenesis by means of IFN stimulated genes (ISG) but the mechanisms underlying the antiviral effects are not clearly understood. IFN induced tetratricopeptide repeats (Ifit) genes are a class of ISGs represented in mice by Ifit1, Ifit2 and Ifit3. Intracranial infection of mice with MHV significantly increases mRNA levels of all 3 Ifit genes in the CNS. Moreover, Ifit2 is beneficial in limiting encephalitis caused by neurotropic viruses like VSV, WNV, EMCV, and MHV. To provide better cellular insights into the protective mechanisms of Ifit2, we studied viral spread and inflammation in young Ifit2−/− mice (4–5 weeks) infected with MHV-A59. Compared to wildtype (wt) viral spread was rapid and uncontrolled in Ifit2−/− mice and mortality was reduced to 70% by day 6–8 p.i. at 2000 PFU. Also, the pattern of virus distribution in spinal cords was significantly different. Where virus was restricted prominently to the gray-white matter border in wt mice, viral antigen expanded to both white and gray matter in Ifit2−/− mice, but they are less inflamed and less encephalitic. Surprisingly, despite vastly elevated virus load, microglia/macrophage activation was limited compared to wt mice as examined by anti-Iba-1 staining. Moreover, leukocyte recruitment was reduced despite similar induction of inflammatory cytokines. By contrast, type I IFN induction was significantly reduced. At lower viral doses (500 PFU), Ifit2−/− mice developed severe clinical symptoms and myelin damage at the chronic infection stage. Given the homeostatic interactions between microglia and neurons, we suggest that Ifit2 deficiency may disrupt microglial activation and protective functions to neurons.

Epidural needle insertion : A large registry analysis

BACKGROUND

Dural puncture, paraesthesia and vascular puncture are the most common complications of epidural catheter insertion. Their association with variation in midline needle insertion depth is unknown.

OBJECTIVE

This study evaluated the risk of dural and vascular punctures and the unwanted events paraesthesia and multiple skin punctures related to midline needle insertion depth.

MATERIAL AND METHODS

A total of 14,503 epidural catheter insertions including lumbar (L1-L5; n = 5367), low thoracic (T7-T12, n = 8234) and upper thoracic (T1-T6, n = 902) insertions, were extracted from the German Network for Regional Anaesthesia registry between 2007 and 2015. The primary outcomes were compared with logistic regression and adjusted (adj) for confounders to determine the risk of complications/events. Results are presented as odds ratios (OR, [95% confidence interval]).

MAIN RESULTS

Midline insertion depth depended on body mass index, sex, and spinal level. After adjusting for confounders increased puncture depth (cm) remained an independent risk factor for vascular puncture (adjOR 1.27 [1.09-1.47], p = 0.002) and multiple skin punctures (adjOR 1.25 [1.21-1.29], p < 0.001). In contrast, dural punctures occurred at significantly shallower depths (adjOR 0.73 [0.60-0.89], p = 0.002). Paraesthesia was unrelated to insertion depth. Body mass index and sex had no influence on paraesthesia, dural and vascular punctures. Thoracic epidural insertion was associated with a lower risk of vascular puncture than at lumbar sites (adjOR 0.39 [0.18-0.84], p = 0.02).

CONCLUSION

Variation in midline insertion depth is an independent risk factor for epidural complications; however, variability precludes use of depth as a reliable guide to insertion in individual patients.

Novel spectrometers for environmental dose rate monitoring

A new generation of dosemeters, based on the scintillators LaBr₃, CeBr₃ and SrI₂, read out with conventional photomultipliers, to be used in the field of environmental gamma-radiation monitoring, was investigated. The main features of these new instruments and especially their outdoor performance, studied by long-term investigations under real weather conditions, are presented. The systems were tested at the reference sites for environmental radiation of the Physikalisch-Technische Bundesanstalt. The measurements are compared with that of well characterized classical dose rate reference instruments to demonstrate the suitability of new spectrometers for environmental dose rate monitoring even in adverse weather conditions. Their potential to replace the (mainly Geiger Müller based) dose rate meters operated in about 5000 European early waning network stations as well as in environmental radiation monitoring in general is shown.

Volumetric comparison of autogenous bone and tissue-engineered bone replacement materials in alveolar cleft repair: a systematic review and meta-analysis

The goal of reconstruction of the alveolar cleft in patients with cleft lip and palate is to improve the quality of tissue, the structural stability, and increase the volume of bone. This study is a systematic review with meta-analysis of volumetric bony filling using autogenous bone and various tissue-engineered bone substitutes. We made an electronic search on MEDLINE, EMBASE, SCOPUS, WEB OF SCIENCE, "grey" publications (materials and research produced by organisations outside traditional channels for commercial or academic publishing and distribution), and relevant cross references according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that reported the outcomes of volumetric grafting were included in the meta-analysis. Of 1276 studies, 26 were included in the meta-analysis. Pooled analysis of 25 studies that used autogenous bone showed a significant reduction in the volume of the cleft equivalent to 62.0% bone fill (95% CI 54.3 to 69.6), in contrast to 10 studies that used a tissue-engineered material and reported bone filling of 68.7% (95% CI 54.5 to 82.8). The estimated sizes of pooled effects across studies showed that there was no significant difference between the two major intervention groups (p value 0.901). Our statistical analysis showed that autogenous bone grafts did not differ significantly from tissue-engineered materials in their ability to fill clefts. Systematic review registration: International Prospective Register of Systematic Reviews, PROSPERO (CRD42017065045).

INFLUENCE OF RADON PROGENY ON DOSE RATE MEASUREMENTS STUDIED AT PTB'S RADON REFERENCE CHAMBER

The responses of electronic dose rate meters were investigated in a large volume radon chamber at PTB in a wide range of radon activity concentrations. The measurements were conducted under controlled laboratory conditions and measured dose rate data are compared with Monte-Carlo simulations. Consequences concerning environmental monitoring are described. A further result is that the direct measurement of the dose rates produced by radon progeny in air is hardly possible in radon atmospheres with high activity concentrations, because the major contribution of measured dose rates is produced by radon progeny on the housing of the dose rate instruments. The latter effect largely depends on the ability of surfaces to absorb radon progeny. The Monte-Carlo simulations revealed quantitative results on the height of the single contributions to the total dose rate measured in the radon chamber. When environmental dose rate measurements are performed, the plate-out on detectors can be neglected.

STING Requires the Adaptor TRIF to Trigger Innate Immune Responses to Microbial Infection

The intracellular microbial nucleic acid sensors, TLR3 and STING, recognize pathogen molecules and signal to activate the interferon pathway. The TIR-domain containing protein TRIF is the sole adaptor of TLR3. Here, we report an essential role for TRIF in STING signaling: various activators of STING could not induce genes in the absence of TRIF. TRIF and STING interacted directly, through their carboxy-terminal domains, to promote STING dimerization, intermembrane translocation, and signaling. Herpes simplex virus (HSV), which triggers the STING signaling pathway and is controlled by it, replicated more efficiently in the absence of TRIF, and HSV-infected TRIF(-/-) mice displayed pronounced pathology. Our results indicate that defective STING signaling may be responsible for the observed genetic association between TRIF mutations and herpes simplex encephalitis in patients.

Peripheral nerve blocks on the upper extremity: Technique of landmark-based and ultrasound-guided approaches

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin, DGAI) established an expert panel to develop preliminary recommendations for the application of peripheral nerve blocks on the upper extremity. The present recommendations state in different variations how ultrasound and/or electrical nerve stimulation guided nerve blocks should be performed. The description of each procedure is rather a recommendation than a guideline. The anaesthesiologist should select the variation of block which provides the highest grade of safety according to his individual opportunities. The first section comprises recommendations regarding dosages of local anaesthetics, general indications and contraindications for peripheral nerve blocks and informations about complications. In the following sections most common blocks techniques on the upper extremity are described.

Tunnelling of thoracic epidural catheters is associated with fewer catheter-related infections: a retrospective registry analysis

BACKGROUND

Catheter-related infections are a serious complication of continuous thoracic epidural analgesia. Tunnelling catheters subcutaneously may reduce infection risk. We thus tested the hypothesis that tunnelling of thoracic epidural catheters is associated with a lower risk of catheter-related infections.

METHODS

Twenty-two thousand, four hundred and eleven surgical patients with continuous thoracic epidural analgesia included in the German Network for Regional Anaesthesia registry between 2007 and 2014 were grouped by whether their catheters were tunnelled (n=12 870) or not (n=9541). Catheter-related infections in each group were compared with Student's unpaired t and χ(2) tests. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated with logistic regression, adjusting for potential confounding factors, including age, ASA physical status score, use of catheter for ≥4 days, multiple skin puncture, hospital, and surgical department.

RESULTS

There were fewer catheter-related infections in patients with tunnelled catheters (4.5 vs 5.5%, P<0.001). Mild infections were also less common (4.0 vs 4.6%, P=0.009), as were moderate infections (0.4 vs 0.8%, P<0.001). After adjustment for potential confounding factors, tunnelling remained an independent prevention for any grade of infection (adjusted OR 0.51, 95% CI 0.42-0.61, P<0.001) and for mild infections (adjusted OR 0.54, 95% CI 0.43-0.66, P<0.001) and moderate and severe infections (adjusted OR 0.44, 95% CI 0.28-0.70, P=0.001).

CONCLUSION

Tunnelling was associated with a lower risk of thoracic epidural catheter-related infections.

Obesity in regional anesthesia--a risk factor for peripheral catheter-related infections

BACKGROUND

Obesity is believed to increase the risk of surgical site infections and possibly increase the risk of catheter-related infections in regional anesthesia. We, therefore, analyzed the influence of obesity on catheter-related infections defined within a national registry for regional anesthesia.

METHODS

The German Network for Regional Anesthesia database with 25 participating clinical centers was analyzed between 2007 and 2012. Exactly, 28,249 cases (13,239 peripheral nerve and 15,010 neuraxial blocks) of patients ≥ 14 years were grouped in I: underweight (BMI 13.2-18.49 kg/m(2) , n = 597), II: normal weight (BMI 18.5-24.9 kg/m(2) , n = 9272), III: overweight (BMI 25.0-29.9 kg/m(2) , n = 10,632), and IV: obese (BMI 30.0-70.3 kg/m(2) , n = 7,744). The analysis focused on peripheral and neuraxial catheter-related infections. Differences between the groups were tested with non-parametric ANOVA and chi-square (P < 0.05). Binary logistic regression was used to compare obese, overweight, or underweight patients with normal weight patients. Odds ratios (OR and 95% confidence interval) were calculated and adjusted for potential confounders.

RESULTS

Confounders with significant influence on the risk for catheter-related infections were gender, age, ASA score, diabetes, preoperative infection, multiple skin puncture, and prolonged catheter use. The incidence (normal weight: 2.1%, obese: 3.6%; P < 0.001) and the risk of peripheral catheter-related infection was increased in obese compared to normal weight patients [adjusted OR: 1.69 (1.25-2.28); P < 0.001]. In neuraxial sites, the incidence of catheter-related infections differed significantly between normal weight and obese patients (normal weight: 3.2%, obese: 2.3%; P = 0.01), whereas the risk was comparable [adjusted OR: 0.95 (0.71-1.28); P = 0.92].

CONCLUSION

This retrospective cohort study suggests that obesity is an independent risk factor for peripheral, but not neuraxial, catheter-related infections.

[Seeing more : Technical innovations in regional anesthesia]

Visualization and verification are key factors since the implementation of ultrasound-guided regional anesthesia. This article reviews and discusses newer technical innovations in regional anesthesia with regard to optimization of needle guidance, improvements in needle visibility, technical improvements in ultrasound techniques and innovative technologies in regional anesthesia. Clinically available applications are presented as well as experimental tools and techniques with a potential for clinical implementation in the future. Mechanical needle guides are used to improve alignment of needle axis and ultrasound beam axis. Compound imaging technology improves needle visibility in steep needle insertion angles and is already implemented in daily clinical practice. Sonoelastography improves tissue discrimination and detection of small amounts of fluids. Benefits of 3D and 4D ultrasound in regional anesthesia are discussed as well as experimental tools for tissue discrimination, such as optical reflection spectrophotometry.

[Perioperative pain management: what is evidence based?]

BACKGROUND

Adequate post-operative acute pain therapy after spinal surgical procedures is essential for many patients. However, patients already receiving chronic opioid therapy pre-operatively present a special challenge for the treating physician during the post-operative period when managing their acute pain. The team must consider multiple approaches of acute pain management and it is important to proceed according to current evidence-based methods.

THERAPY

A wide spectrum of options for pain management after spinal surgery is currently available. This includes various therapeutic methods as well as regional anesthesia. Considering the various options, the method of choice for post-operative analgesia depends on the expected pain, therapy effectiveness, and the applicability with regard to potential side-effects.

METHOD

In addition to the basic analgesic therapy consisting of opioid and non-opioid drugs, chronic pain patients may require co-analgesics or combination analgesics from this class.

CONCLUSION

Regional anesthesia is currently the predominant method of choice for post-operative acute pain management. Neuraxial blockage is especially important when considering all spinal procedures.

[Localization of peripheral nerves. Success and safety with electrical nerve stimulation]

Peripheral electrical nerve stimulation is one of the standard applications in peripheral regional anesthesia in addition to the ultrasound technique. Among other findings, the visualization of needle and nerve during ultrasound-guided blockade caused a change in clinical practice of peripheral nerve stimulation in the last decade. In the present article old and new aspects of principles and clinical practice of the nerve stimulation technique are presented and summarized in a total clinical concept in order to achieve safe and successful peripheral regional anesthesia using electrical peripheral nerve stimulation.

Survival after curative surgical treatment for primary oral squamous cell carcinoma

The purpose of this retrospective study was to review recurrence rate and survival of patients with primary oral squamous cell carcinoma (OSCC) that have received surgical treatment and adjuvant radio-therapy with curative intent in our clinic over a 6-year period. A total of 106 patients were included. The 5-year overall survival (OS) was 41%, 5-year disease-specific survival (DSS) was 77%, 5-year disease-free survival (DFS) was 72%. DSS was significantly different between early and advanced stage, 87% and 67% respectively (p = 0.04). Recurrence significantly affected survival: OS with or without recurrence at 20 months was 24% and 87% respectively (p < 0.001). Although a guideline based approach for the treatment of OSCC might provide an advantage, more data are needed for these guidelines to be based on.

Endoskopisch unterstützte LeFort-I-Osteotomie bei Distraktionsverfahren im Oberkiefer

PURPOSE

The purpose of this study was to demonstrate the feasibility of combining a minimally invasive endoscopic approach to the maxilla with transverse and sagittal distraction procedures.

MATERIALS AND METHODS

Four human cadavers were used for training of a minimally invasive access to the maxilla to perform an endoscopically assisted Le Fort I osteotomy, before this technique was applied in three patients with transverse and sagittal growth deficits of the maxilla. Access to the maxilla was gained through a small mucosa incision in the vestibule to create a visualization port to the maxillary sinus through a bur hole. Landmarks were identified through the endoscope before a Le Fort I osteotomy was performed using straight and angulated chisels of different form and angulation. In two patients, the maxilla was split sagittally to perform a transverse maxillary expansion. In one patient, a buried distractor was applied close to the piriform aperture to correct a sagittal growth deficit in a hypoplastic maxilla.

RESULTS

The endoscopic exposure of the maxillary sinus walls from within the sinus, the accurate identification of landmarks, and the creation of a Le Fort I osteotomy was achieved in all cases. Distractor application close to the piriform aperture rendered good stability.

CONCLUSION

The results of these case reports indicate that the endoscopic approach to the maxillary sinus allows excellent exposure of the sinus walls to perform an endoscopically assisted Le Fort I osteotomy. The combination of endoscopy and osteodistraction supports the trend toward minimally invasive, less traumatic surgical procedures, especially in individuals still growing.

Distribution of delta opioid receptor-expressing neurons in the mouse hippocampus

Delta opioid receptors participate to the control of chronic pain and emotional responses. Recent data also identified their implication in spatial memory and drug-context associations pointing to a critical role of hippocampal delta receptors. We examined the distribution of delta receptor-expressing cells in the hippocampus using fluorescent knock-in mice that express a functional delta receptor fused at its carboxyterminus with the green fluorescent protein in place of the native receptor. Colocalization with markers for different neuronal populations was performed by immunohistochemical detection. Fine mapping in the dorsal hippocampus confirmed that delta opioid receptors are mainly present in GABAergic neurons. Indeed, they are mostly expressed in parvalbumin-immunopositive neurons both in the Ammon's horn and dentate gyrus. These receptors, therefore, most likely participate in the dynamic regulation of hippocampal activity.

Impact of a Mycobacterium tuberculosis-specific interferon-γ release assay in bronchoalveolar lavage fluid for a rapid diagnosis of tuberculosis

OBJECTIVES

Evaluation of different methods for an initial treatment decision in individuals with suspected pulmonary tuberculosis.

BACKGROUND

Recently, important advances regarding the diagnosis of pulmonary tuberculosis have been introduced, which influence the decision to initiate anti-tuberculosis treatment.

METHODS

To evaluate the impact of different methods for the presumed diagnosis of tuberculosis, individuals with suspected tuberculosis were prospectively enrolled following a specific algorithm including initial smear microscopy and Mycobacterium tuberculosis-specific nucleic acid amplification (NAAT) from sputum. In cases of negative initial test results, tuberculin skin testing, bronchoscopy with transbronchial biopsies and interferon-γ release assays (IGRAs) in peripheral blood and bronchoalveolar lavage (BAL) fluid were performed.

RESULTS

Amongst 135 individuals with suspected tuberculosis, 42 had tuberculosis, 10 had nontuberculous mycobacteria pulmonary infection/colonization (one had both tuberculosis and nontuberculous mycobacteria pulmonary infection/colonization) and 84 had an alternative final diagnosis. The sensitivity and specificity were 41% and 99% [positive likelihood ratio (LR+) = 40] for sputum microscopy and 31% and 98% (LR+) = 16) for BAL nucleic acid amplification, respectively. In patients with acid-fast bacilli smear-negative tuberculosis (25/42, 59.5%), M. tuberculosis-specific BAL fluid IGRA was 92% sensitive and 87% specific (LR+) = 7) for the diagnosis of tuberculosis.

CONCLUSION

None of the microbiological or immunological methods that aim to provide a rapid diagnosis of tuberculosis whilst waiting the confirmation of the M. tuberculosis culture results is on its own accurate enough to diagnose or exclude pulmonary tuberculosis. Negative sputum microscopy and M. tuberculosis-specific NAAT results should prompt bronchoscopy including BAL for M. tuberculosis-specific IGRA in individuals with suspected pulmonary tuberculosis.

Inhibition of RNase L and RNA-dependent protein kinase (PKR) by sunitinib impairs antiviral innate immunity

RNase L and RNA-dependent protein kinase (PKR) are effectors of the interferon antiviral response that share homology in their pseudokinase and protein kinase domains, respectively. Sunitinib is an orally available, ATP-competitive inhibitor of VEGF and PDGF receptors used clinically to suppress angiogenesis and tumor growth. Sunitinib also impacts IRE1, an endoplasmic reticulum protein involved in the unfolded protein response that is closely related to RNase L. Here, we report that sunitinib is a potent inhibitor of both RNase L and PKR with IC(50) values of 1.4 and 0.3 μM, respectively. In addition, flavonol activators of IRE1 inhibited RNase L. Sunitinib treatment of wild type (WT) mouse embryonic fibroblasts resulted in about a 12-fold increase in encephalomyocarditis virus titers. However, sunitinib had no effect on encephalomyocarditis virus growth in cells lacking both PKR and RNase L. Furthermore, oral delivery of sunitinib in WT mice resulted in 10-fold higher viral titers in heart tissues while suppressing by about 2-fold the IFN-β levels. In contrast, sunitinib had no effect on viral titers in mice deficient in both RNase L and PKR. Also, sunitinib reduced mean survival times from 12 to 6 days in virus-infected WT mice while having no effect on survival of mice lacking both RNase L and PKR. Results indicate that sunitinib treatments prevent antiviral innate immune responses mediated by RNase L and PKR.

Low molecular weight heparins for thromboprophylaxis during induction chemotherapy in patients with multiple myeloma

BACKGROUNDS

Patients with multiple myeloma have a high risk of venous thromboembolism (VTE), especially during the induction chemotherapy. The aim of our observational study was to determine the impact of prophylaxis with low molecular weight heparin (LMWH) on the incidence of thromboembolic complications.

PATIENTS AND METHODS

We analyzed the incidence of thromboembolic events in 258 patients treated with induction chemotherapy containing vincristin, doxorubicin or idarubicin, and dexamethasone, followed by stimulation chemotherapy with cyclophosphamide and G-CSF, and high-dose chemotherapy with melphalan. Two groups of these patients were compared based on the practice of thromboprophylaxis. Patients in the first group (Control, n = 140) were either not treated or treated with a short duration of anticoagulation therapy while the patients in the second group (Prophylactic, n = 118) underwent standard prophylaxis with LMWH throughout the entire period of induction chemotherapy. A total of 102 patients were selected for a close monitoring of the prophylactic effect of different LMWH doses and to be compared to patients without treatment.

RESULTS

Standard prophylaxis with LMWH significantly (p < 0.007) lowered a risk of VTE when compared to patients without such prophylaxis (3.4% versus 12.9%, respectively). Furthermore, analysis of the subgroup of 102 patients revealed that higher LMWH doses (> 70 IU/kg per day) achieved full prophylaxis in 28 patients while lower doses were less effective leading to DVT in 3 (7.7%) out of 39 patients. In contrast, VTE was diagnosed in 5 (14.3%) out of 35 patients without any LMWH prophylaxis.

CONCLUSION

Prophylaxis with LMWH leads to a significant reduction of the risk of thromboembolic complications during the induction chemotherapy in patients suffering from MM. The prophylactic effect of LMWH is dose-dependent.