Accuracy of low-weight versus standard syringe infusion pump devices depending on altitude.

BACKGROUND: Intravenous drug infusions in critically ill patients require accurate syringe infusion pumps (SIPs). This is particularly important during transportation of critically ill patients by helicopter emergency medical services (HEMS), where altitude may influence device performance. Because weight is a real concern in HEMS, new low-weight devices are very appealing. The aim of this study was to compare infusion flow rates delivered by low-weight versus standard SIP devices, in the prehospital emergency medicine setting, at different altitudes. METHODS: We conducted a comparative bench study involving five SIP devices (two standard and three low-weight models) at 300, 1700 and 3000 m altitude. The primary endpoint was the flow rate delivered by SIPs for prespecified values. We used two methods to measure flow. The normative method consisted in measuring weight (method A) and the alternate method consisted in measuring instantaneous flow (method B). RESULTS: Using method A, no significant differences were found in median flow rates and interquartile range depending on device and altitude for a prespecified 10-mL/h flow. However, method B showed that low-weight SIPs delivered multiple sequential boluses with substantial variations (1.2-15.8 mL/h) rather than a prespecified continuous 5-mL/h flow. At 1700 m altitude, the interquartile range of delivered flows increased only for low-weight devices (p for interaction< 0.001). CONCLUSIONS: Despite satisfactory normative tests, low-weight SIPs deliver discontinuous flow with potential clinical implications for critically ill patients receiving vasoactive drugs. This study also highlights a thus far unknown negative impact of altitude on SIP function. We believe that normative requirements for SIP approval should be revised accordingly.

Intranasal sufentanil versus intravenous morphine for acute severe trauma pain: A double-blind randomized non-inferiority study.

BACKGROUND: Intravenous morphine (IVM) is the most common strong analgesic used in trauma, but is associated with a clear time limitation related to the need to obtain an access route. The intranasal (IN) route provides easy administration with a fast peak action time due to high vascularization and the absence of first-pass metabolism. We aimed to determine whether IN sufentanil (INS) for patients presenting to an emergency department with acute severe traumatic pain results in a reduction in pain intensity non-inferior to IVM. METHODS AND FINDINGS: In a prospective, randomized, multicenter non-inferiority trial conducted in the emergency departments of 6 hospitals across France, patients were randomized 1:1 to INS titration (0.3 µg/kg and additional doses of 0.15 µg/kg at 10 minutes and 20 minutes if numerical pain rating scale [NRS] > 3) and intravenous placebo, or to IVM (0.1 mg/kg and additional doses of 0.05 mg/kg at 10 minutes and 20 minutes if NRS > 3) and IN placebo. Patients, clinical staff, and research staff were blinded to the treatment allocation. The primary endpoint was the total decrease on NRS at 30 minutes after first administration. The prespecified non-inferiority margin was -1.3 on the NRS. The primary outcome was analyzed per protocol. Adverse events were prospectively recorded during 4 hours. Among the 194 patients enrolled in the emergency department cohort between November 4, 2013, and April 10, 2016, 157 were randomized, and the protocol was correctly administered in 136 (69 IVM group, 67 INS group, per protocol population, 76% men, median age 40 [IQR 29 to 54] years). The mean difference between NRS at first administration and NRS at 30 minutes was -4.1 (97.5% CI -4.6 to -3.6) in the IVM group and -5.2 (97.5% CI -5.7 to -4.6) in the INS group. Non-inferiority was demonstrated (p < 0.001 with 1-sided mean-equivalence t test), as the lower 97.5% confidence interval of 0.29 (97.5% CI 0.29 to 1.93) was above the prespecified margin of -1.3. INS was superior to IVM (intention to treat analysis: p = 0.034), but without a clinically significant difference in mean NRS between groups. Six severe adverse events were observed in the INS group and 2 in the IVM group (number needed to harm: 17), including an apparent imbalance for hypoxemia (3 in the INS group versus 1 in the IVM group) and for bradypnea (2 in the INS group versus 0 in the IVM group). The main limitation of the study was that the choice of concomitant analgesics, when they were used, was left to the discretion of the physician in charge, and co-analgesia was more often used in the IVM group. Moreover, the size of the study did not allow us to conclude with certainty about the safety of INS in emergency settings. CONCLUSIONS: We confirm the non-inferiority of INS compared to IVM for pain reduction at 30 minutes after administration in patients with severe traumatic pain presenting to an emergency department. The IN route, with no need to obtain a venous route, may allow early and effective analgesia in emergency settings and in difficult situations. Confirmation of the safety profile of INS will require further larger studies. TRIAL REGISTRATION: ClinicalTrials.gov NCT02095366. EudraCT 2013-001665-16.

E2F transcription factor-1 regulates oxidative metabolism.

Cells respond to stress by coordinating proliferative and metabolic pathways. Starvation restricts cell proliferative (glycolytic) and activates energy productive (oxidative) pathways. Conversely, cell growth and proliferation require increased glycolytic and decreased oxidative metabolism levels. E2F transcription factors regulate both proliferative and metabolic genes. E2Fs have been implicated in the G1/S cell-cycle transition, DNA repair, apoptosis, development and differentiation. In pancreatic ß-cells, E2F1 gene regulation facilitated glucose-stimulated insulin secretion. Moreover, mice lacking E2F1 (E2f1(-/-)) were resistant to diet-induced obesity. Here, we show that E2F1 coordinates cellular responses by acting as a regulatory switch between cell proliferation and metabolism. In basal conditions, E2F1 repressed key genes that regulate energy homeostasis and mitochondrial functions in muscle and brown adipose tissue. Consequently, E2f1(-/-) mice had a marked oxidative phenotype. An association between E2F1 and pRB was required for repression of genes implicated in oxidative metabolism. This repression was alleviated in a constitutively active CDK4 (CDK4(R24C)) mouse model or when adaptation to energy demand was required. Thus, E2F1 represents a metabolic switch from oxidative to glycolytic metabolism that responds to stressful conditions.

miR-143 interferes with ERK5 signaling, and abrogates prostate cancer progression in mice.

BACKGROUND: Micro RNAs are small, non-coding, single-stranded RNAs that negatively regulate gene expression at the post-transcriptional level. Since miR-143 was found to be down-regulated in prostate cancer cells, we wanted to analyze its expression in human prostate cancer, and test the ability of miR-43 to arrest prostate cancer cell growth in vitro and in vivo. RESULTS: Expression of miR-143 was analyzed in human prostate cancers by quantitative PCR, and by in situ hybridization. miR-143 was introduced in cancer cells in vivo by electroporation. Bioinformatics analysis and luciferase-based assays were used to determine miR-143 targets. We show in this study that miR-143 levels are inversely correlated with advanced stages of prostate cancer. Rescue of miR-143 expression in cancer cells results in the arrest of cell proliferation and the abrogation of tumor growth in mice. Furthermore, we show that the effects of miR-143 are mediated, at least in part by the inhibition of extracellular signal-regulated kinase-5 (ERK5) activity. We show here that ERK5 is a miR-143 target in prostate cancer. CONCLUSIONS: miR-143 is as a new target for prostate cancer treatment.

CXC ligand 5 is an adipose-tissue derived factor that links obesity to insulin resistance.

We show here high levels of expression and secretion of the chemokine CXC ligand 5 (CXCL5) in the macrophage fraction of white adipose tissue (WAT). Moreover, we find that CXCL5 is dramatically increased in serum of human obese compared to lean subjects. Conversely, CXCL5 concentration is decreased in obese subjects after a weight reduction program, or in obese non-insulin-resistant, compared to insulin-resistant, subjects. Most importantly we demonstrate that treatment with recombinant CXCL5 blocks insulin-stimulated glucose uptake in muscle in mice. CXCL5 blocks insulin signaling by activating the Jak2/STAT5/SOCS2 pathway. Finally, by treating obese, insulin-resistant mice with either anti-CXCL5 neutralizing antibodies or antagonists of CXCR2, which is the CXCL5 receptor, we demonstrate that CXCL5 mediates insulin resistance. Furthermore CXCR2-/- mice are protected against obesity-induced insulin resistance. Taken together, these results show that secretion of CXCL5 by WAT resident macrophages represents a link between obesity, inflammation, and insulin resistance.

Regulator of G protein signaling-4 controls fatty acid and glucose homeostasis.

Circulating free fatty acids are a reflection of the balance between lipogenesis and lipolysis that takes place mainly in adipose tissue. We found that mice deficient for regulator of G protein signaling (RGS)-4 have increased circulating catecholamines, and increased free fatty acids. Consequently, RGS4-/- mice have increased concentration of circulating free fatty acids; abnormally accumulate fatty acids in liver, resulting in liver steatosis; and show a higher degree of glucose intolerance and decreased insulin secretion in pancreas. We show in this study that RGS4 controls adipose tissue lipolysis through regulation of the secretion of catecholamines by adrenal glands. RGS4 controls the balance between adipose tissue lipolysis and lipogenesis, secondary to its role in the regulation of catecholamine secretion by adrenal glands. RGS4 therefore could be a good target for the treatment of metabolic diseases.