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Rationale: Until recently, the survival rate in patients with Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) was approximately 30%. Tyrosine kinase inhibitors (TKIs), which are a new class of drugs that target BCR-ABL fusion protein, have shown to be effective in treating Ph+ ALL in adults. However, the resistance mechanisms that promote the disease recurrence have altered the initial success of these revolutionary agents., Patient Concerns: A 71-year-old Chinese female patient who suffered from severe shoulder and back pain for 1 week., Diagnosis: The patient was diagnosed with Ph+ ALL (B-cell) because of the following items. Complete blood count showed extremely abnormal white blood cell count (26.26×109/l), hemoglobin concentration (65 g/l) and platelet count (14×109/l). And because that Bone marrow aspirate showed 72.5% lymphoblasts and 59.30% lymphoblasts were confirmed by flow cytometry (FCM). At mean time, Real-time fluorescent quantitative PCR analysis confirmed that the P190 BCR/ABL fusion gene expression was 5.9%. Karyotype analysis indicated the following: 45, XX, -7, t (922) (q34; q11) [cp3]., Interventions: The patient was treated with chemotherapy and different TKIs including imatinib, dasatinib, ponatinib, and bosutinib., Outcomes: The patient achieved complete remissions with different TKIs after diagnose but relapsed afterward and died of infection., Lessons: Multidrug-resistant mutations within the BCR-ABL1 kinase domain are an emerging clinical problem for patients receiving sequential TKIs therapy. Acquisition of E255K/V-inclusive mutations is usually associated with ponatinib resistance, thus it is necessary to screen out new real pan-inhibitor compounds for all BCR/ABL mutations and figure out the potential efficacy of asciminib-based drug combinations in the future., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

HASPIN has been identified as a nuclear Ser/Thr kinase specifically expressed in haploid germ cells. HASPIN kinase inhibitors were recently isolated, and their antitumor activity reported. Colorectal cancer occurs with high incidence worldwide. In this study, we examined whether HASPIN inhibitor CHR-6494 suppresses cancer progression in Apc mice, a familial colon tumor disease model. Mice were treated by intraperitoneal injection of CHR-6494 for 50 days. Following the treatment period, intestinal polyps were counted and testosterone and spermatogenesis levels were observed. Intraperitoneal administration of CHR-6494 significantly inhibited intestinal polyp development and recovered body weight in Apc mice. Although spermatogenesis was inhibited with increasing age in Apc mice, CHR-6494 significantly improved blood testosterone levels and spermatogenesis. Our results suggest that HASPIN inhibitors may be useful as anti-cancer agents and for the treatment of hypogonadism in colorectal cancer patients.

Relaxation and changes in the transmembrane potential of vascular smooth muscle induced by ORM-3819, a novel inodilating compound, were investigated in isolated porcine coronary arteries. Isometric tone was studied on arterial rings precontracted by KCl (30 mM), and resting membrane potential was investigated by a conventional microelectrode technique. ORM-3819 in the concentration range 0.38-230.6 µM evoked concentration-dependent relaxation with a maximum value of 58.1% and an effective concentration of the relaxing substance that caused 50% of maximum relaxation of 72.2 µM. The maximum hyperpolarization produced by ORM-3819 at a concentration of 120 µM (-2.6 ± 0.81 mV, N = 10) did not differ significantly from that induced by C-type natriuretic peptide (CNP), an endogenous hyperpolarizing mediator, at a concentration of 1.4 µM (-3.6 ± 0.38 mV, N = 17). The same effect elicited by the known inodilator levosimendan was less pronounced at a concentration of 3.7 µM: -1.82 ± 0.44 mV, N = 22 (P < 0.05 vs. CNP). The voltage-gated potassium channel inhibitor 4-aminopyridine, at a concentration of 5 mM, attenuated the relaxation induced by ORM-3819 at concentrations of 41.6 or 117.2 µM. These results suggest that ORM-3819 is a potent vasodilating agent able to relieve coronary artery vasospasm by causing hyperpolarization of vascular smooth muscle cells through processes involving activation of voltage-gated potassium channels.

Objective- Venous malformations (VMs) arise from developmental defects of the vasculature and are characterized by massively enlarged and tortuous venous channels. VMs grow commensurately leading to deformity, obstruction of vital structures, bleeding, and pain. Most VMs are associated with the activating mutation L914F in the endothelial cell (EC) tyrosine kinase receptor TIE2. Therapeutic options for VM are limited and ineffective while therapy with the mammalian target of rapamycin inhibitor rapamycin shows moderate efficacy. Here, we investigated novel therapeutic targets promoting VM regression. Approach and Results- We performed an unbiased screen of Food and Drug Administration-approved drugs in human umbilical vein ECs expressing the TIE2-L914F mutation (HUVEC-TIE2-L914F). Three ABL (Abelson) kinase inhibitors prevented cell proliferation of HUVEC-TIE2-L914F. Moreover, c-ABL, common target of these inhibitors, was highly phosphorylated in HUVEC-TIE2-L914F and VM patient-derived ECs with activating TIE2 mutations. Knockdown of c-ABL/ARG in HUVEC-TIE2-L914F reduced cell proliferation and vascularity of murine VM. Combination treatment with the ABL kinase inhibitor ponatinib and rapamycin caused VM regression in a xenograft model based on injection of HUVEC-TIE2-L914F. A reduced dose of this drug combination was effective in this VM murine model with minimal side effects. The drug combination was antiproliferative, enhanced cell apoptosis and vascular channel regression both in vivo and in a 3-dimensional fibrin gel assay. Conclusions- This is the first report of a combination therapy with ponatinib and rapamycin promoting regression of VM. Mechanistically, the drug combination enhanced AKT inhibition compared with single drug treatment and reduced PLCγ (phospholipase C) and ERK (extracellular signal-regulated kinase) activity.

Propofol as an agonist of GABAA receptor has a rewarding and discriminative stimulus effect. However, which subtype of the GABAA receptor is involved in the discriminative stimulus effects of propofol is still not clear. We observed the effects of an agonist or an antagonist of the subtype-selective GABAA receptor on discriminative stimulus effects of propofol. Male Sprague-Dawley rats were trained to discriminate 10 mg/kg (intraperitoneal) propofol from intralipid under a fixed-ratio 10 schedule of food reinforcement. We found that propofol produced dose-dependent substitution for propofol at 10 mg/kg, with response rate reduction only at a dose above those producing the complete substitution. CL218,872 (1-3 mg/kg, intraperitoneal), an α1 subunit-selective GABAA receptor agonist, and SL651,498 (0.3-3 mg/kg, intraperitoneal), an α2/3 GABAA receptor selective agonist, could partially substitute for the discriminative stimulus effects of propofol (40-80% propofol-appropriate responding). Meanwhile, L838,417 (0.2-0.6 mg/kg, intravenous), a α2/3/5 GABAA receptor selective agonist, could produce near 100% propofol-appropriate responding and completely substitute for propofol effects. Moreover, the administration of L655,708, the α5 GABAA receptor inverse agonist, could dose dependently attenuate the discriminative stimulus of propofol. In contrast, the α1 GABAA receptor antagonist β-CCt (1-3 mg/kg) combined with propofol (10 mg/kg) failed to block the propofol effect. The data showed that propofol produces discriminative stimulus effects in a dose-dependent manner and acts mainly on the α5 GABAA to produce the discriminative stimulus effect.

Background: We investigated whether chronic levosimendan treatment can prevent and revert right ventricular (RV) failure and attenuate pulmonary vascular remodeling in a rat model of pulmonary arterial hypertension (PAH)., Methods and Results: PAH was induced in rats by exposure to SU5416 and hypoxia (SuHx). The rats were randomized to levosimendan (3 mg·kg·d) initiated before SuHx (n = 10, PREV), levosimendan started 6 weeks after SuHx (n = 12, REV), or vehicle treatment (n = 10, VEH). Healthy control rats received vehicle (n = 10, CONT). Ten weeks after SuHx, RV function was evaluated by echocardiography, magnetic resonance imaging, invasive pressure-volume measurements, histology, and biochemistry. Levosimendan treatment improved cardiac output (VEH vs. PREV 77 ± 7 vs. 137 ± 6 mL/min; P < 0.0001; VEH vs. REV 77 ± 7 vs. 117 ± 10 mL/min; P < 0.01) and decreased RV afterload compared with VEH (VEH vs. PREV 219 ± 33 vs. 132 ± 20 mm Hg/mL; P < 0.05; VEH vs. REV 219 ± 33 vs. 130 ± 11 mm Hg/mL; P < 0.01). In the PREV group, levosimendan restored right ventriculoarterial coupling (VEH vs. PREV 0.9 ± 0.1 vs. 1.8 ± 0.3; P < 0.05) and prevented the development of pulmonary arterial occlusive lesions (VEH vs. PREV 37 ± 7 vs. 15 ± 6% fully occluded lesions; P < 0.05)., Conclusion: Chronic treatment with levosimendan prevents and reverts the development of RV failure and attenuates pulmonary vascular remodeling in a rat model of PAH.

Purpose of Review: In the last years, the perioperative use of levosimendan in cardiac surgery patients is spreading. Moreover, newer indications have been suggested such as the treatment of sepsis-associated myocardial dysfunction. In the present review, we discuss the most recent evidences in these settings., Recent Findings: Levosimendan has been seemingly confirmed to reduce mortality in patients undergoing cardiac surgery. In particular, it appears to be the only inotropic drug to have a favorable effect on survival in any clinical setting. Moreover, levosimendan has been shown to exert a cardioprotective action and to reduce acute kidney injury, renal replacement therapy, and ICU stay in cardiac surgery patients. Finally, levosimendan has been suggested to reduce mortality in patients with severe sepsis and to improve renal outcomes in critically ill patients., Summary: Although a strong rationale likely exists to use levosimendan in the setting of perioperative and critical care medicine, evidence mainly comes from small and often poor-quality randomized clinical trials, whose results acquire significance only when pooled in meta-analyses. Moreover, some aspects related to which subgroups of patients may derive the most benefits from receiving levosimendan, to the optimal timing of administration, and to the potential adverse effects need to be further clarified. Important insights will be hopefully provided soon by the several large multicenter investigations which are currently ongoing.

Background: We investigated if chronic levosimendan treatment can prevent and revert pressure-overload-induced right ventricular hypertrophy and failure in rats., Methods: Right ventricular hypertrophy and failure was induced in Wistar rats by pulmonary trunk banding (PTB). The PTB rats were treated with levosimendan (3 mg·kg·d) 3 days before surgery [n = 10, prevention (PREV)], 3 weeks after surgery [n = 10, reversal (REV)] or vehicle (n = 10, VEH). Sham-operated rats received vehicle (n = 16, SHAM). Right ventricular function was evaluated 7 weeks after surgery by echocardiography, magnetic resonance imaging, pressure-volume relations, gross anatomy, and histology., Results: PTB induced right ventricular hypertrophy and compensated heart failure evident by reduced cardiac index (CI) without extra cardiac signs of heart failure. Levosimendan treatment prevented deterioration of right ventricular function measured by CI and right ventricular ejection fraction (RVEF) (CI: VEH vs. PREV 281 ± 17 vs. 362 ± 34 mL·min·kg, P ≤ 0.05, RVEF: VEH vs. PREV 57 ± 2% vs. 68 ± 3%, P ≤ 0.01) to values similar to SHAM (CI: 345 ± 21 mL·min·kg, RVEF: 71 ± 2%). RV contractility was improved in the REV group measured by preload recruitable stroke work (VEH vs. REV 39 ± 3 vs. 66 ± 10 mmHg P ≤ 0.05)., Conclusions: Chronic treatment with levosimendan prevents the development of right ventricular failure and improves contractility in established pressure-overload-induced right ventricular failure.

Objectives: The calcium sensitizer levosimendan is used in treatment of decompensated heart failure and may also exhibit anti-inflammatory properties. We examined whether treatment with levosimendan is substantially beneficial in mice with cecal ligation and puncture-induced polymicrobial sepsis, and its arbitration mechanism was explored in the mouse macrophage cell line RAW264.7., Design: Laboratory and animal/cell research., Setting: University research laboratory., Subjects: BALB/c mice (8-10 wk old) and mouse macrophage cell line RAW264.7 cells., Interventions: Levosimendan (0.5 μg/kg/min) was administered to mice through an osmotic pump that was implanted into the peritoneal cavity immediately following surgery. In RAW264.7 cells, levosimendan was added to the culture medium 30 minutes before lipopolysaccharide., Measurements and Main Results: When levosimendan was continuously administered to cecal ligation and puncture-induced septic mice, a significant improvement of left ventricular function was found without any change in heart rate, and hypotension was significantly mitigated. Furthermore, levosimendan conferred substantial protection against sepsis-associated inflammation in mice, as indicated by reduced lung injury and decreased blood proinflammatory and chemotactic cytokine levels. These beneficial effects of levosimendan led to a significant improvement of survival in mice after cecal ligation and puncture. In endotoxin-stimulated RAW264.7 macrophages, treatment with levosimendan and pimobendan suppressed overproduction of proinflammatory and chemotactic cytokines. Levosimendan and pimobendan were without effect on activation of the nuclear factor-κB, mitogen-activated protein kinase, and Akt pathways. Instead, levosimendan and pimobendan prevented high mobility group box 1 release from the nucleus to the extracellular space in macrophages. This was associated with inhibition of the Rho kinase signaling pathway. The elevated serum high mobility group box 1 levels in cecal ligation and puncture-induced septic mice were also inhibited by continued administration of levosimendan and pimobendan., Conclusions: We define a novel mechanism for the anti-inflammatory action of levosimendan and suggest that the pharmacological profiles of levosimendan as both an inotrope and an anti-inflammatory agent could contribute to its clinical benefit in patients with sepsis with heart problems.

Propofol is a rapid-acting sedative-hypnotic medication that has been widely used for the induction and maintenance of anesthesia; it has specific actions on different areas of the brain, such as sensory information transmission in the somatosensory cortex. However, the effects of propofol on the properties of sensory stimulation-evoked responses in cerebellar Purkinje cells (PCs) are currently unclear. In the present study, we studied the effects of propofol on facial stimulation-evoked responses in cerebellar PCs and molecular level interneurons (MLIs) in urethane-anesthetized mice using electrophysiological and pharmacological methods. Our results showed that cerebellar surface perfusion with propofol induced a decrease in the amplitude of the gamma-aminobutyric acid (GABA)-ergic component (P1) in a dose-dependent manner, but induced a significant increase in the amplitude of the excitatory response (N1). The IC50 of propofol-induced inhibition of P1 was 217.3 μM. In contrast, propofol (100 μM) depressed the spontaneous activity and tactile-evoked responses in MLIs. In addition, blocking GABA(A) receptor activity abolished the propofol (300 μM)-induced inhibition of the tactile-evoked inhibitory response and the increase in the sensory stimulation-evoked spike firing rate of PCs. These results indicated that propofol depressed the tactile stimulation-evoked spike firing of MLIs, resulting in a decrease in the amplitude of the tactile-evoked inhibitory response and an increase in the amplitude of the excitatory response in the cerebellar PCs of mice. Our results suggest that propofol modulates sensory information processing in cerebellar cortical PCs and MLIs through the activation of GABA(A) receptors.

Purpose: To compare the efficacy of levosimendan with nitroglycerin in patients with isolated diastolic dysfunction undergoing coronary artery bypass grafting., Procedure: Thirty patients with isolated diastolic dysfunction undergoing on-pump coronary artery bypass grafting were randomized into 2 groups receiving levosimendan or nitroglycerin infusion. The infusion was started before sternotomy and continued in the postoperative period. Perioperatively, diastolic function was serially evaluated at 3 different time points using echocardiography. N-terminal fragment of pro-B-natriuretic peptide (NT-proBNP) levels were measured in both the groups., Results: There was a significant improvement in diastolic function as measured by isovolumic relaxation time (P = 0.0001, P = 0.001) and deceleration time (P = 0.0001, P = 0.0001) in the levosimendan group from the baseline in patients with impaired relaxation. Similarly, tissue Doppler imaging also revealed an improvement from the baseline in patients with a pseudonormal pattern (P = 0.018, P = 0.001). Furthermore, there was a significant improvement in the above parameters when compared with the nitroglycerin group. The NT-proBNP levels also demonstrated a similar pattern between the 2 groups (P = 0.03, P = 0.02) when levosimendan was compared with nitroglycerin in patients with a pseudonormal pattern on echocardiography., Conclusions: Levosimendan is superior to nitroglycerin in improving diastolic function irrespective of coronary revascularization.

This study was designed to assess the progression of pulmonary arterial hypertension (PAH) and the effectiveness of therapy using recently investigated echocardiographic parameters. PAH is characterized by the progressive elevation of pulmonary artery pressure and right ventricular hypertrophy and dysfunction, which ultimately results in right-sided heart failure and death. Echocardiography results and invasive measurements of right and left ventricular systolic pressures were compared after 3-week administrations of sildenafil (S group), pimobendan (P group), nicorandil (N group), and their combinations (SP and SPN groups) in male rats with monocrotaline (MCT)-induced pulmonary hypertension (M group) and without this condition (C group). The groups that received pimobendan alone and in combinations (SP and SPN groups) showed improvement in their echocardiographic parameters of systolic function. A significant improvement of diastolic function was achieved in the SPN group. Invasive measurements showed the most significant decreases of right ventricular systolic pressure in the N and SPN groups, and the use of pimobendan resulted in a comparatively low risk of adverse hemodynamic effects (left ventricular systolic pressure). Although our results suggested the attenuation of PAH severity in all treatment groups, PAH could not be reversed.

Levosimendan is a calcium-sensitizing agent shown to prevent myocardical contractile depression in various heart diseases. In this study, we investigated the effect of levosimendan on cardiac dysfunction and apoptosis in hypothermic preservation rat hearts. Isolated rat hearts were preserved in Celsior solution with or without levosimendan. The left ventricular developed pressure (LVDP) recovery rate of isolated rat heart significantly decreased, and the apoptosis index increased after 9 hours of hypothermic preservation. Supplement Celsior solution with levosimendan (10 and 10 mole/L) enhanced the LVDP recovery rate and reduced apoptosis. Levosimendan inhibited the hypothermic preservation-induced calpain activation and cleavage of Bid. Levosimendam induced increased myocardial inducible nitric oxide synthase but not endothelial nitric oxide synthase expression. A selective inducible nitric oxide synthase inhibitor 1400W, and a mitochondrial ATP-sensitive potassium (KATP) channel blocker 5-hydroxydecanoate but not a sarcolemmal KATP channel blocker HMR-1098 prevented improvement effect of levosimendam on LVDP recovery rate, abolished the inhibitory effect of levosimendan on hypothermic preservation-induced activation of calpain, cleavage of Bid, and apoptosis. These data suggested that Celsior solution supplement with levosimendan improved cardiac function recovery and reduced myocyte apoptosis in hypothermic preservation rat hearts.

Objectives: Despite advances in cardiac arrest treatment, high mortality and morbidity rates after successful cardiopulmonary resuscitation are still a major clinical relevant problem. The post cardiac arrest syndrome subsumes myocardial dysfunction, impaired microcirculation, systemic inflammatory response, and neurological impairment. The calcium-sensitizer levosimendan was able to improve myocardial function and initial resuscitation success after experimental cardiac arrest/cardiopulmonary resuscitation. We hypothesized that levosimendan exerts beneficial effects on cerebral blood flow, neuronal injury, neurological outcome, and inflammation 24 hours after experimental cardiac arrest/cardiopulmonary resuscitation., Design: Laboratory animal study., Setting: University animal research laboratory., Subjects: Sixty-one male Sprague-Dawley rats., Interventions: Animals underwent asphyxial cardiac arrest/cardiopulmonary resuscitation, randomized to groups with levosimendan treatment (bolus 12 µg/kg and infusion for 3 hr [0.3 µg/min/kg]) or vehicle (saline 0.9% bolus and infusion for 3 hr [equivalent fluid volume]). Cardiac index, local cerebral blood flow, and hemodynamic variables were measured for 180 minutes after cardiac arrest/cardiopulmonary resuscitation. Behavioral and neurological evaluations were conducted 24 hours after cardiac arrest/cardiopulmonary resuscitation. Furthermore, neuronal injury, expressed as Fluoro-Jade B-positive cells in the hippocampal formation, cortical and hippocampal inflammatory cytokine gene expression, and blood plasma interleukin-6 values were assessed., Measurements and Main Results: Treatment with levosimendan reduced neuronal injury and improved neurological outcome after 24 hours of reperfusion and resulted in elevated cardiac index and local cerebral blood flow compared with vehicle after cardiac arrest/cardiopulmonary resuscitation. Mean arterial blood pressure was reduced during the early reperfusion period in the levosimendan group. Cortical and hippocampal inflammatory cytokine gene expression and blood plasma interleukin-6 levels were not influenced., Conclusions: Levosimendan increased cerebral blood flow after experimental cardiac arrest/cardiopulmonary resuscitation. This effect coincided with reduced neuronal injury and improved neurologic outcome. Findings seem to be independent of inflammatory effects because no effects by levosimendan on cerebral or systemic inflammation could be detected. In summary, levosimendan is a promising agent to improve neurological outcome after cardiac arrest/cardiopulmonary resuscitation.

Aims: Optimization of inotropic treatment in worsening heart failure sometimes requires invasive hemodynamic assessment in selected patients. Impedance cardiography (ICG) may be useful for a noninvasive hemodynamic evaluation., Methods: ICG was performed in 40 patients (69 ± 8 years; left ventricular ejection fraction 27.5 ± 5.6%; New York Heart Association 3.18 ± 0.34; Interagency Registry for Mechanically Assisted Circulatory Support 5.48 ± 0.96, before and after infusion of Levosimendan (0.1–0.2 µg/kg per min for up to 24 h). Echocardiogram, ICG [measuring cardiac index (CI), total peripheral resistances (TPRs) and thoracic fluid content (TFC)] and plasma levels of brain natriuretic peptide (BNP) were obtained; in nine patients, right heart catheterization was also carried out., Results: When right catheterization and ICG were performed simultaneously, a significant relationship was observed between values of CI and TPR, and between TFC and pulmonary wedge pressure. ICG detected the Levosimendan-induced recovery of the hemodynamic status, associated with improved systolic and diastolic function and reduction in BNP levels. One-year mortality was 4.4%. At multivariate analysis, independent predictors of mortality were: no improvement in the severity of mitral regurgitation, a persistent restrictive filling pattern (E/E’ > 15), a reduction of BNP levels below 30% and a change below 10% in CI, TPR and TFC. When combined, absence of hemodynamic improvement at ICG could predict 1-year mortality with better sensitivity (86%) and specificity (85%) than the combination of echocardiographic and BNP criteria only (sensitivity 80% and specificity 36%)., Conclusion: Noninvasive hemodynamic evaluation of heart failure patients during infusion of inodilator drugs is reliable and may help in their prognostic stratification.

Objectives: Acute kidney injury develops in a large proportion of patients after cardiac surgery because of the low cardiac output syndrome. The inodilator levosimendan increases cardiac output after cardiac surgery with cardiopulmonary bypass, but a detailed analysis of its effects on renal perfusion, glomerular filtration, and renal oxygenation in this group of patients is lacking. We therefore evaluated the effects of levosimendan on renal blood flow, glomerular filtration rate, renal oxygen consumption, and renal oxygen demand/supply relationship, i.e., renal oxygen extraction, early after cardiac surgery with cardiopulmonary bypass., Design: Prospective, placebo-controlled, and randomized trial., Setting: Cardiothoracic ICU of a tertiary center., Patients: Postcardiac surgery patients (n=30)., Interventions: The patients were randomized to receive levosimendan, 0.1 µg/kg/min after a loading dose of 12 µg/kg (n=15), or placebo (n=15)., Measurements and Main Results: The experimental procedure started 4-6 hours after surgery in the ICU during propofol sedation and mechanical ventilation. Systemic hemodynamic were evaluated by a pulmonary artery thermodilution catheter. Renal blood flow and glomerular filtration rate were measured by the renal vein retrograde thermodilution technique and by renal extraction of Cr-EDTA, respectively. Central venous pressure was kept constant by colloid/crystalloid infusion. Compared to placebo, levosimendan increased cardiac index (22%), stroke volume index (15%), and heart rate (7%) and decreased systemic vascular resistance index (21%), whereas mean arterial pressure was not affected. Levosimendan induced significant increases in renal blood flow (12%, p<0.05) and glomerular filtration rate (21%, p<0.05), decreased renal vascular resistance (18%, p<0.05) but caused no significant changes in filtration fraction, renal oxygen consumption, or renal oxygen extraction, compared to placebo., Conclusions: After cardiac surgery with cardiopulmonary bypass, levosimendan induces a vasodilation, preferentially of preglomerular resistance vessels, increasing both renal blood flow and glomerular filtration rate without jeopardizing renal oxygenation. Due to its pharmacodynamic profile, levosimendan might be an interesting alternative for treatment of postoperative heart failure complicated by acute kidney injury in postcardiac surgery patients.

Objective: The current in-vitro study examined HIV-1 drug resistance patterns following etravirine (ETR) and rilpivirine (RPV) drug pressure in viruses containing baseline nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations., Design and Method: Several baseline mutations were introduced into NL-4.3 (subtype B clone) by site-directed mutagenesis. This virus, together with two subtype C clinical isolates containing baseline mutations, was passaged in increasing drug pressure of NNRTIs in cord blood mononuclear cells. Genotypic analysis was performed at different weeks. Phenotypic resistance for ETR, RPV, and efavirenz (EFV) and the replication capacity of several mutations and combinations were tested., Results: In wild-type viruses and viruses containing K103N alone at baseline, E138K or E138G mutations were observed following pressure with either ETR or RPV prior to the appearance of other NNRTI resistance mutations. These changes were observed regardless of viral subtype. However, subtype B viruses containing Y181C generated V179I/F or A62V/A but not E138K following exposure to ETR or RPV, respectively, whereas subtype C viruses containing Y181C developed E138V together with Y188H and V179I under ETR pressure. The addition of mutations at position 138 to Y181C did not significantly enhance levels of resistance to ETR or RPV. The replicative capacity of viruses containing Y181C and either E138K or E138A was similar to that of viruses containing either E138K or E138A alone., Conclusion: These results demonstrate that ETR and RPV are likely to select for E138K as a major resistance mutation if no or very few other resistance mutations are present and that Y181C may be antagonistic to E138K.

Objectives: Etravirine (ETV) is metabolized by cytochrome P450 (CYP) 3A, 2C9, and 2C19. Metabolites are glucuronidated by uridine diphosphate glucuronosyltransferases (UGT). To identify the potential impact of genetic and non-genetic factors involved in ETV metabolism, we carried out a two-step pharmacogenetics-based population pharmacokinetic study in HIV-1 infected individuals., Materials and Methods: The study population included 144 individuals contributing 289 ETV plasma concentrations and four individuals contributing 23 ETV plasma concentrations collected in a rich sampling design. Genetic variants [n=125 single-nucleotide polymorphisms (SNPs)] in 34 genes with a predicted role in ETV metabolism were selected. A first step population pharmacokinetic model included non-genetic and known genetic factors (seven SNPs in CYP2C, one SNP in CYP3A5) as covariates. Post-hoc individual ETV clearance (CL) was used in a second (discovery) step, in which the effect of the remaining 98 SNPs in CYP3A, P450 cytochrome oxidoreductase (POR), nuclear receptor genes, and UGTs was investigated., Results: A one-compartment model with zero-order absorption best characterized ETV pharmacokinetics. The average ETV CL was 41 (l/h) (CV 51.1%), the volume of distribution was 1325 l, and the mean absorption time was 1.2 h. The administration of darunavir/ritonavir or tenofovir was the only non-genetic covariate influencing ETV CL significantly, resulting in a 40% [95% confidence interval (CI): 13-69%] and a 42% (95% CI: 17-68%) increase in ETV CL, respectively. Carriers of rs4244285 (CYP2C19*2) had 23% (8-38%) lower ETV CL. Co-administered antiretroviral agents and genetic factors explained 16% of the variance in ETV concentrations. None of the SNPs in the discovery step influenced ETV CL., Conclusion: ETV concentrations are highly variable, and co-administered antiretroviral agents and genetic factors explained only a modest part of the interindividual variability in ETV elimination. Opposing effects of interacting drugs effectively abrogate genetic influences on ETV CL, and vice-versa., (© 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.)

Background: Recent clinical trials with rilpivirine combined with emtricitabine and tenofovir revealed that patients failing treatment, frequently, harbored viruses encoding resistance-associated mutations in the HIV-1 reverse transcriptase at position E138K and M184I. We show here that APOBEC3 proteins play a role in the emergence of these drug resistance mutations., Methods: We used a Vif mutant that has suboptimal activity against APOBEC3 to assess the in-vitro frequency of APOBEC3-induced resistance mutations in reverse transcriptase. To assess the degree of in-vivo G-to-A viral hypermutation, a large amount of data of HIV-1 RT proviral sequences from peripheral blood mononuclear cells (PBMCs) recovered from infected patients under HAART was analyzed., Results: In-vitro replication experiments in cell lines with and without APOBEC3 expression suggest that APOBEC3-driven mutagenesis contributes to the generation of both M184I and E138K within HIV proviral repository in the absence of drug exposure. Additionally, analysis of 601 patients PBMCs sequences revealed that the copresence of mutations E138K and M184I were never detected in nonhypermutated sequences, whereas these mutations were found at a high frequency (24%) in the context of APOBEC3 editing and in the absence of exposure to etravirine-rilpivirine., Conclusion: We demonstrate using in-vitro experiments and analyzing patients PBMCs sequences that M184I and E138K resistance-associated mutations may pre-exist in proviral reservoir at a high frequency prior to drug exposure, as a result of APOBEC3 editing. Thus, incomplete neutralization of one or more APOBEC3 proteins may favor viral escape to rilpivirine-emtricitabine., (© 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins)

Objectives: The objectives of the present study were (i) to identify a novel tumor suppressor gene whose expression level was regulated by transforming growth factor (TGF-β) and (ii) to evaluate the effect of Ras/MEK/ERK signaling on TGF-β-dependent Lefty up-regulation., Methods: Human pancreatic cancer cell lines were used. The effect of Ras/MEK/ERK pathway on TGF-β-mediated Lefty up-regulation was tested by adding K-ras small interfering RNA, MEK inhibitor U0126, or extracellular signal-regulated kinase (ERK) inhibitor LY294002., Results: Transforming growth factor β upregulated Lefty messenger RNA levels within 6 of the 7 cell lines. Lefty exerts an antagonistic effect against the tumor-promoting molecule, Nodal, as recombinant Lefty suppressed Nodal-mediated proliferation. Interestingly, inhibition of the Ras/MEK/ERK pathway dramatically enhanced TGF-mediated Lefty up-regulation, suggesting that Ras/MEK/ERK signaling suppresses TGF-β-Lefty pathway., Conclusions: Our data suggest that Lefty is a novel TGF-β target molecule that mediates growth inhibition of pancreatic cancer cells. In addition, activation of the Ras/MEK/ERK pathway serves as a mechanism by which pancreatic cancer escapes from growth inhibition by the TGF-β-Lefty axis. The results imply a novel therapeutic strategy for pancreatic cancer, that is, combination treatment with Ras/MEK/ERK inhibitors and TGF-β.

Background: Microglial inhibition may reduce secondary tissue injury and improve functional outcome following acute brain injury. Utilizing clinically relevant murine models of traumatic brain injury and intracerebral hemorrhage, neuroinflammatory responses and functional outcome were examined in the presence of a potential microglial inhibitor, TT-301., Methods: TT-301 or saline was administered following traumatic brain injury or intracerebral hemorrhage, and then for four subsequent days. The effect of TT-301 on neuroinflammatory responses and neuronal viability was assessed, as well as short-term vestibulomotor deficit (Rotorod) and long-term neurocognitive impairment (Morris water maze). Finally differential gene expression profiles of mice treated with TT-301 were compared with those of vehicle., Results: Reduction in F4/80+ staining was demonstrated at 1 and 10 days, but not 28 days, after injury in mice treated with TT-301 (n = 6). These histologic findings were associated with improved neurologic function as assessed by Rotorod, which improved by 52.7% in the treated group by day 7, and Morris water maze latencies, which improved by 232.5% as a function of treatment (n = 12; P < 0.05). Similar benefit was demonstrated following intracerebral hemorrhage, in which treatment with TT-301 was associated with functional neurologic improvement of 39.6% improvement in Rotorod and a reduction in cerebral edema that was independent of hematoma volume (n = 12; P < 0.05). Differential gene expression was evaluated following treatment with TT-301, and hierarchical cluster analysis implicated involvement of the Janus kinase-Signal Transducer and Activator of Transcription pathway after administration of TT-301 (n = 3/group)., Conclusions: Modulation of neuroinflammatory responses through TT-301 administration improved histologic and functional parameters in murine models of acute neurologic injury.

Objective: Levosimendan enhances cardiac contractility by increasing myocyte sensitivity to calcium and causing vasodilatation. Although studies have evaluated the efficacy of levosimendan in heart failure, whether levosimendan produces an effect on platelets is a subject of controversy. In the present study, the in-vitro effect of levosimendan on platelet aggregation was investigated. The effect of levosimendan on the cyclic AMP concentration was determined according to its second mode of action as a selective phosphodiesterase III inhibitor., Materials and Methods: Platelet aggregation setting was performed using venous blood from three healthy volunteers. Different concentrations of levosimendan solution were prepared that would result in 0.04-125 µg/ml levosimendan concentrations in whole blood and in platelet-enriched plasma. After incubation for 3 min at 37°C, aggregation responses were evaluated with ADP (10 µmol/l), collagen (5 µg/ml), or NaCl. The cyclic AMP concentration was determined using the enzyme-linked immunosorbent assay technique., Results: The in-vitro results clearly showed that there was only a relationship between a high levosimendan concentration (12-125 µg/ml) and inhibition of platelet aggregation that was negatively dependent on the cAMP concentration., Conclusion: Levosimendan has no significant effect as a phosphodiesterase III inhibitor on in-vitro platelet aggregation in clinically relevant doses.

Background: Levosimendan was hypothesized to attenuate hypoxic pulmonary vasoconstriction (HPV)., Methods: Fourteen anaesthetized pigs (30.9 ± 1.0 kg) were studied in normoxia (FiO₂∼0.21) and hypoxia (FiO₂∼0.10), before and 10-90 minutes after infusion of placebo (n = 7) or levosimendan (n = 7)., Results: Compared with normoxia, hypoxia baseline at FiO₂∼0.10 (n = 14) increased pulmonary vascular resistance (PVR) by 1.9 ± 0.4 Wood Units (WU) (P < 0.001), mean pulmonary artery pressure (MPAP) by 14.3 ± 0.9 mm Hg (P < 0.001), mean right atrial pressure (MRAP) by 2.1 ± 0.4 mm Hg (P < 0.001), pulmonary capillary wedge pressure (PCWP) by 1.5 ± 0.3 mm Hg (P < 0.001), cardiac output (CO) by 1.3 ± 0.2 L/minute (P < 0.001) and heart rate (HR) by 19.9 ± 5.5 beats·per minute (P < 0.001). Systemic vascular resistance (SVR) decreased by 7.2 ± 1.0 WU (P < 0.001), MAP and stroke volume (SV) remained unaltered (P = ns). Compared with hypoxia baseline, levosimendan decreased MPAP and PVR (P < 0.05), by approximately 9% and 19%, respectively, plateauing between 10 and 90 minutes. SV increased (P < 0.05) by approximately 22%, plateauing after 60 minutes. MRAP, PCWP, HR, CO, MAP, SVR, and blood-O₂ consumption remained unaltered (P = ns). Compared with hypoxia baseline, with placebo, MPAP remained stable (P = ns), PVR increased (P < 0.05) and CO decreased (P < 0.05) by approximately 20% and 11% after 60-90 and 30-90 minutes, respectively. SV decreased (P < 0.05) by approximately 8%, plateauing after 60-90 minutes. PCWP and MRAP decreased (P < 0.05) by approximately 12%, plateauing after 10-60 and 10-90 minutes, respectively. MPAP, HR, MAP, SVR, and blood-O₂ consumption remained unchanged (P = ns), except at 60 minutes where MAP decreased (P < 0.05) by approximately 4%., Conclusions: Levosimendan attenuated HPV and the cardiodepressive effect of sustained hypoxia.

Prevalence of etravirine genotypic resistance was assessed among 92 HIV-1C-infected patients failing nevirapine and efavirenz-based regimens from a cohort of 552 Indian patients. Overall, prevalence of etravirine cross-resistance identified using the Tibotec Weighted Score was 41% (31.5% intermediately-resistant and 9.8% fully-resistant). The most frequently described nonnucleoside reverse transcriptase inhibitor-associated mutations included Y181 (35.9%), K101 (20.7%), G190 (17.4%), and V108 (15.2%). The resistant group demonstrated higher viral load (P = 0.01) and longer duration of antiretroviral treatment (P = 0.03) compared with the susceptible group.

Levosimendan exerts cardioprotection through mitochondrial K(ATP) (mitoK(ATP)) channels opening. In addition, intracoronary levosimendan was found to modulate programmed forms of cell death by nitric oxide (NO) involvement. The aim of this study was to examine the role of mitoK(ATP) channels and NO in the effects of levosimendan on apoptosis/autophagy. In H9c2 cells treated with hydrogen peroxide apoptosis/autophagy, survival signaling, cell viability, mitochondrial membrane potential, and permeability transition pore opening were analyzed through Western blot and colorimetric and fluorescence assays. Pretreatment of H9c2 cells with levosimendan was able to counteract the oxidative injuries caused by hydrogen peroxide. The effects of levosimendan were potentiated by diazoxide and were similar to those elicited by the autophagic activator rapamycin. The autophagic inhibitor 3-methyladenine reduced the effects of levosimendan, whereas after the pan-caspases inhibitor N-Acetyl-Asp-Glu-Val-Asp-al (Z-VAD.FMK), cell survival and autophagy in response to levosimendan increased. Both the mitoK(ATP) channels inhibition and the NO synthase blocking attenuated the cardioprotection elicited by levosimendan. The results have shown that levosimendan protects H9c2 cells against oxidative injuries through the modulation of the interplay between autophagy and apoptosis and the activation of survival signaling. The mitoK(ATP) channels and NO may be involved in such cardioprotection through interference with mitochondrial functioning.

Objectives: ANRS 139 TRIO trial was a phase II noncomparative trial that evaluated in highly experienced patients, a combination of raltegravir, etravirine and darunavir boosted with ritonavir. We analyzed emergence of resistant viruses at the time of virological failure and investigated the impact of baseline integrase polymorphisms on virological failure occurrence., Methods: Bulk sequencing of protease, reverse transcriptase and integrase genes was performed for 103 patients at baseline and 14 patients at the time of virological failure. Additionally, integrase clonal analyses were performed at baseline and at virological failure in patients with successful integrase gene amplification. Impact of baseline integrase polymorphisms on virological failure occurrence was analyzed using Fisher exact and Wilcoxon tests., Results: In the 14 failing patients median viral load at virological failure was 90 copies/ml (interquartile range = 60-783). Emergence of darunavir and etravirine resistance mutations was observed at virological failure in only one and three patients, respectively. Raltegravir resistance mutations were found neither at baseline nor at the time of virologic failure. Integrase clonal analyses showed neither the presence nor the selection of minority variants carrying raltegravir resistance mutations at baseline or at virological failure. No impact of baseline integrase polymorphisms was observed on virological failure either at week 24 or at week 48., Conclusion: Virological failure occurred in a small proportion of patients with low viral load. No raltegravir resistance mutations were observed using bulk sequencing or clonal analyses, and darunavir and etravirine resistance-associated mutations were detected in only one and three patients, respectively at virological failure. No impact of baseline integrase polymorphism was observed on virological failure occurrence.

Objective: To compare the effects of a first-line therapy of combined arginine vasopressin, levosimendan, and norepinephrine with arginine vasopressin + norepinephrine or norepinephrine alone in ovine septic shock., Design: Prospective, randomized, controlled laboratory experiment., Setting: University animal research facility., Subjects: Twenty-one chronically instrumented sheep., Interventions: After the onset of fecal peritonitis-induced septic shock (mean arterial pressure <60 mm Hg), sheep were randomly assigned to receive first-line treatment with arginine vasopressin (0.5 mU·kg·min), combined arginine vasopressin (0.5 mU·kg·min) and levosimendan (0.2 μg·kg·min), or normal saline (each n = 7) for 24 hrs. In all groups, open-label norepinephrine was additionally titrated to maintain mean arterial pressure at 70 ± 5 mm Hg, if necessary., Measurements and Main Results: Arginine vasopressin + levosimendan + norepinephrine improved left ventricular contractility (higher stroke work indices at similar or lower preload) and pulmonary function (Pao2/Fio2 ratio) when compared with the other groups (p < .05 each). Both nonadrenergic treatment strategies reduced open-label norepinephrine doses. However, only arginine vasopressin + levosimendan + norepinephrine limited fluid requirements and positive fluid balance vs. both other groups (p < .05 each). In addition, arginine vasopressin + levosimendan + norepinephrine increased mixed venous oxygen saturation as compared with arginine vasopressin + norepinephrine. Histologic tissue analyses and pulmonary hemeoxygenase-1 activity revealed no differences among groups. Notably, arginine vasopressin + levosimendan + norepinephrine therapy reduced pulmonary 3-nitrotyrosine levels (p = .028 vs. control animals) as well as urinary protein/creatinine ratio (p < .05 each) and slightly prolonged survival when compared with both other groups (4 hrs vs. arginine vasopressin + norepinephrine: p = .013; 7 hrs vs. norepinephrine alone: p = .003)., Conclusions: First-line cardiovascular support with combined arginine vasopressin and levosimendan supplemented with norepinephrine improves myocardial, vascular, pulmonary, and renal function as compared with arginine vasopressin + norepinephrine in septic shock.

In septic patients, myocardial depression-the so-called septic cardiomyopathy-needing inotropic support is common. The aim of this study was to compare the dose-responsive electrophysiological and mechanical properties concerning metabolic effects of clinically available inotropic agents in an isolated septic rat heart model. After 20 h of incubation, both sham-operated and septic (cecal ligation and single puncture) hearts from male Wistar rats (n = 64) were isolated and received dobutamine, dopamine, epinephrine, or levosimendan at concentrations of 10 to 10 M. Electrophysiological, mechanical, and metabolic properties were measured, and the myocardial oxygen supply-demand ratio and cardiac efficiency were calculated. With the exception of levosimendan, all of the drugs tested showed dose-dependent, significantly positive changes in chronotropy, inotropy, and lusitropy in all hearts. Maximum increases in septic hearts were dose-dependent and were ordered as follows: epinephrine > dopamine > dobutamine >>> levosimendan. These increases in cardiac performance were accompanied by a decrease in the myocardial oxygen supply-demand ratio. However, cardiac efficiency was significantly improved in the epinephrine-treated septic hearts. With the drug-induced increase in cardiac performance, the myocardial oxygen supply-demand ratio decreased proportionally in the epinephrine-, dobutamine-, and dopamine-treated septic hearts. However, epinephrine showed the most favorable results with regard to cardiac efficiency, and levosimendan showed no beneficial effect in septic hearts with regard to efficiency in this study.

It has been proposed that vasodilatory therapy may increase microcirculatory blood flow and improve tissue oxygenation in septic shock. The authors aimed to evaluate the effects of levosimendan in systemic and splanchnic hemodynamics in a porcine model of septic shock in a randomized animal controlled study. This study was performed in an animal research facility in a university hospital. Anesthetized pigs were monitored with a pulmonary artery catheter and an ultrasonic blood flow probe in the portal vein for measurement of systemic and portal blood flows and with a tonometer placed in the small intestine for measurement of the intramucosal-arterial PCO2 gap. Three groups of pigs were studied: nonseptic (n = 7), septic (n = 7), and septic treated with levosimendan (n = 7). Levosimendan was administered i.v. at t = -10 min (200 microg/kg in i.v. bolus followed by 200 microg/kg per h). Sepsis was induced at t = 0 min by the administration of live Escherichia coli. Vascular reactivity was tested by the hemodynamic response to noradrenaline. Levosimendan markedly attenuated the sepsis-induced increase in pulmonary vascular resistance, decrease in portal/systemic blood flow, oliguria, impairment in oxygenation, hyperkalemia, and the widened intramucosal-arterial PCO2 gap. Systemic blood pressure and vascular resistance did not differ as compared with the septic untreated group. Responses to noradrenaline significantly improved in animals treated with levosimendan. Treatment with levosimendan in this animal model of sepsis attenuated pulmonary vasoconstriction and improved portal blood flow, intestinal mucosal oxygenation, pulmonary function, and vascular reactivity.

The aim of this study is to report the development of cardiac failure after subarachnoid hemorrhage (SAH) with recovery of heart and cerebral function. This is a case report of a 38-year-old woman who was admitted to the intensive care unit (ICU) at Policlinico di Modena, Italy. This woman developed a deep state of coma because of severe SAH. After cerebral hemorrhage, patient showed a cardiogenic shock, which needed invasive monitoring. Cerebral perfusion pressure had to be restored, so fluids, dopamine, norepinephrine, and dobutamine were in administered sequentially. Despite these supportive treatments, hemodynamic parameters further worsened and echocardiography showed a global depressed left ventricular (LV) contraction with poor ejection fraction (EF) and restrictive type of LV relaxation pattern. Twenty-four hours after ICU admission, levosimendan was started with the aim to improve cardiac function because of the refractoriness of all other treatments. Eight hours after levosimendan infusion, cardiac function improved and, within the after 24 hours, EF and LV relaxation pattern recovered. Neurologic state and computed tomography images improved day by day, and after 9 days from the ICU admission, we transferred the patient to the neurosurgical ward with very good neurologic conditions and no deficits in motility. The conventional management of post-SAH cardiovascular failure is based on the use of norepinephrine, dobutamine, and high amount of fluids. This strategy did not provide any improvement, so we decided for levosimendan infusion to counteract myocardial stunning. The improvement in cardiac EF, LV wall motion, and filling pressure observed in our patient could be explained due to the antistunning triple-mechanism action of levosimendan. Data available on the levosimendan effectiveness in patients with SAH and its effect on intracranial pressure are still lacking, but we think that neurogenic cardiac failure can be treated at first with levosimendan.

Etravirine is a recently approved nonnucleoside reverse transcriptase inhibitor. The ability of etravirine to limit the emergence of resistance to protease inhibitors, and specifically to darunavir, was investigated in the subset of treatment-experienced patients with virologic rebound in the phase III DUET trials. Of those experiencing rebound, fewer etravirine-treated than placebo-treated patients developed mutations associated with resistance to protease inhibitors in general and to darunavir in particular, and more patients in the etravirine than the placebo-group maintained baseline darunavir susceptibility at endpoint.

Background: We addressed the hypothesis that the inotropic drugs dobutamine and levosimendan both induce surplus oxygen consumption (oxygen wasting) relative to their contractile effect in equipotent therapeutic doses, with levosimendan being energetically more efficient., Methods and Results: Postischemically reduced left ventricular function (stunning) was created by repetitive left coronary occlusions in 22 pigs. This contractile dysfunction was reversed by infusion of either levosimendan (24 microg/kg loading and 0.04 microg x kg(-1) x min(-1) infusion) or an equipotent dose of dobutamine (1.25 microg x kg(-1) x min(-1)). Contractility and cardiac output were normalized by both drug regimens. The energy cost of drug-induced contractility enhancement was assessed by myocardial oxygen consumption related to the mechanical indexes tension-time index, pressure-volume area, and total mechanical energy. ANCOVA did not reveal any increased oxygen cost of contractility for either drug in these doses. However, both dobutamine and levosimendan at supratherapeutic levels (10 microg x kg(-1) x min(-1) and 48 microg/kg loading with 0.2 microg x kg(-1) x min(-1) infusion, respectively) induced a highly significant increase in oxygen consumption related to mechanical work, compatible with the established oxygen-wasting effect of inotropy (P<0.001 for all mechanical indexes with dobutamine; P=0.007 for levosimendan as assessed by pressure-volume area)., Conclusions: Therapeutic levels of neither dobutamine nor levosimendan showed inotropic oxygen wasting in this in vivo pig model. Thus, relevant hemodynamic responses can be achieved with an adrenergic inotrope without surplus oxygen consumption.

Objective: To refine the genotypic and phenotypic correlates of response to the nonnucleoside reverse transcriptase inhibitor etravirine., Design: Initial analyses identified 13 etravirine resistance-associated mutations (RAMs) and clinical cutoffs (CCOs) for etravirine. A multivariate analysis was performed to refine the initial etravirine RAM list and improve the predictive value of genotypic resistance testing with regard to virologic response and relationship to phenotypic data., Methods: Week 24 data were pooled from the phase III studies with TMC125 to Demonstrate Undetectable viral load in patients Experienced with ARV Therapy (DUET). The effect of baseline resistance to etravirine on virologic response (<50 HIV-1 RNA copies/ml) was studied in patients not using de-novo enfuvirtide and excluding discontinuations for reasons other than virologic failure (n = 406). Clinical cutoffs for etravirine were established by analysis of covariance models and sliding fold change in 50% effective concentration (EC50) windows (Antivirogram; Virco BVBA, Mechelen, Belgium). Etravirine RAMs were identified as those associated with decreased virologic response/increased etravirine fold change in EC50. Relative weight factors were assigned to the etravirine RAMs using random forest and linear modeling techniques., Results: Baseline etravirine fold change in EC50 predicted virologic response at week 24, with lower and preliminary upper clinical cutoffs of 3.0 and 13.0, respectively. A fold change in EC50 value above which etravirine provided little or no additional efficacy benefit could not be established. Seventeen etravirine RAMs were identified and attributed a relative weight factor accounting for the differential impact on etravirine fold change in EC50. Virologic response was a function of etravirine-weighted genotypic score., Conclusion: The weighted genotypic scoring algorithm optimizes resistance interpretations for etravirine and guides treatment decisions regarding its use in treatment-experienced patients.

Objectives: Levosimendan improves left ventricular hemodynamic function in patients with cardiogenic shock. However, its impact on right ventricular performance has not been determined. We compared the hemodynamic effects of levosimendan on left and right ventricular function in patients with intractable cardiogenic shock following myocardial infarction., Design: Observational hemodynamic study., Setting: Tertiary care center university hospital., Patients: Fifty-six patients with cardiogenic shock secondary to myocardial infarction were treated with percutaneous revascularization (including intra-aortic balloon pump when appropriate) and commenced on conventional inotropic therapy., Intervention: Twenty-five consecutive patients with cardiogenic shock due to myocardial infarction who had not improved sufficiently with conventional therapy (including dobutamine and norepinephrine) received levosimendan (as a bolus of 12 microg/kg per minute for 10 mins then 0.1 microg/kg per minute--0.2 mug/kg per minute) as "bail-out" therapy for 24 hrs while invasive hemodynamic parameters were recorded., Measurements and Main Results: Levosimendan therapy was associated with a significant increase in cardiac index from 2.1 +/- 0.1 to 3.0 +/- 0.2 L x min x m (p < .01). In addition, levosimendan enhanced right ventricular cardiac power index (0.14 +/- 0.19 to 0.18W +/- 0.12, p < .001), while pulmonary vascular resistance fell from 227.7 +/- 94.5 to 178.1 +/- 62.3 dyne x s x cm (p = .002). No significant change in central venous pressure or mean pulmonary artery pressure was observed. The observed hemodynamic improvement was sustained after the levosimendan infusion was stopped., Conclusions: Levosimendan infusion for cardiogenic shock following acute myocardial infarction improved hemodynamic parameters of right ventricular performance. Furthermore, we describe the use of right ventricular cardiac power index as a hemodynamic parameter of right ventricular performance.

Objective: To evaluate the efficacy, safety and virologic resistance profile of etravirine (TMC125), a next-generation nonnucleoside reverse transcriptase inhibitor, over 48 weeks in treatment-experienced adults infected with HIV-1 strains resistant to a nonnucleoside reverse transcriptase inhibitor and other antiretrovirals., Design: DUET-1 (NCT00254046) and DUET-2 (NCT00255099) are two identically designed, randomized, double-blind phase III trials., Methods: Patients received twice-daily etravirine 200 mg or placebo, each plus a background regimen of darunavir/ritonavir, investigator-selected nucleoside/nucleotide reverse transcriptase inhibitors and optional enfuvirtide. Eligible patients had documented nonnucleoside reverse transcriptase inhibitor resistance, at least three primary protease inhibitor mutations at screening and were on a stable but virologically failing regimen for at least 8 weeks, with plasma viral load more than 5000 copies/ml. Pooled 48-week data from the two trials are presented., Results: Patients (1203) were randomized and treated (n = 599, etravirine; n = 604, placebo). Significantly more patients in the etravirine than in the placebo group achieved viral load less than 50 copies/ml at week 48 (61 vs. 40%, respectively; P < 0.0001). Significantly fewer patients in the etravirine group experienced at least one confirmed or probable AIDS-defining illness/death (6 vs. 10%; P = 0.0408). Safety and tolerability in the etravirine group was comparable to the placebo group. Rash was the only adverse event to occur at a significantly higher incidence in the etravirine group (19 vs. 11%, respectively, P < 0.0001), occurring primarily in the second week of treatment., Conclusion: At 48 weeks, treatment-experienced patients receiving etravirine plus background regimen had statistically superior and durable virologic responses (viral load less than 50 copies/ml) than those receiving placebo plus background regimen, with comparable tolerability and no new safety signals reported since week 24.

Purpose of Review: This review focuses on the use of tipranavir/ritonavir, darunavir/ritonavir and etravirine for the treatment of HIV infection that has become resistant to protease inhibitors and/or nonnucleoside reverse transcriptase inhibitors., Recent Findings: Tipranavir/ritonavir and darunavir/ritonavir are boosted protease inhibitors highly active against HIV that has developed mutations that confer resistance to other protease inhibitors. For both drugs, there are scores to predict activity based on a combination of mutations. Best results are obtained when each drug is combined with one and preferably two other completely active antiretrovirals. The interaction profile and toxicity profile is better for darunavir/ritonavir, which in addition has shown positive outcomes in clinical trials of patients with early failure.Etravirine is a nonnucleoside reverse transcriptase inhibitor highly active against HIV that has developed mutations that confer resistance to nevirapine or efavirenz. Clinical trials results suggest that etravirine should be used with other active antiretrovirals. Best results for etravirine have been obtained in combination with darunavir/ritonavir in patients with extensive protease inhibitor and nonnucleoside reverse transcriptase inhibitor resistance. The role of etravirine for the treatment of early failure of efavirenz-based or nevirapine-based regimens remains to be elucidated. Resistance to etravirine requires the accumulation of multiple reverse transcriptase mutations different from K103N, which has no impact on activity., Summary: Tipranavir/ritonavir, darunavir/ritonavir and etravirine are very important additions to the therapeutic armamentarium against HIV that has become resistant to protease inhibitors and nonnucleoside reverse transcriptase inhibitors.

Background: Septic shock may cause splanchnic hypoperfusion. We hypothesized that levosimendan would improve systemic and hepatosplanchnic perfusion during endotoxemic shock., Methods: In 16 anesthetized pigs (31.4 +/- 3.4 kg), a jugular vein, a carotid artery, the pulmonary artery (thermodilution), the portal vein, and a hepatic vein were cannulated for hemodynamic monitoring and blood sampling. Ultrasonic flowprobes were placed around the portal vein, the hepatic artery, and the superior mesenteric artery (SMA). In addition to 30 mL/kg of dextran 70 given before baseline, all animals received 10 mL x kg(-1) x h(-1) of IV fluids throughout the experiment. An endotoxin infusion (2 microg x kg(-1) x h(-1)) was given for 300 min; 100 min after the start of endotoxin, the pigs were randomized to receive levosimendan (50 microg x kg(-1) x h(-1), n = 8) or placebo (n = 8). To evaluate the isolated effects of endotoxemia, all data before randomization were pooled into one group. Data were analyzed by analysis of variance and presented as mean +/- sem., Results: Endotoxemia (t = 90 min, pooled data) decreased systemic vascular resistance (SVR, 2526 +/- 203 to 1946 +/- 122 dyn x s x cm(-5), P = 0.003) and mean arterial blood pressure (MAP, 109 +/- 6 to 84 +/- 3 mm Hg, P < 0.05), whereas heart rate (66 +/- 4 to 98 +/- 8 bpm), and mean pulmonary arterial pressure (MPAP, 20 +/- 1 to 38 +/- 2 mm Hg) increased (P < 0.001). Cardiac output (CO, 3.4 +/- 0.2 L/min) and systemic oxygen delivery (414 +/- 33 mL/min) were unchanged, but blood flows in the SMA (575 +/- 34 to 392 +/- 38 mL/min) and the portal vein (881 +/- 62 to 568 +/- 39 mL/min) decreased (P < 0.001). Although hepatic arterial blood flows increased (36 +/- 8 to 219 +/- 38 mL/min), gut (114 +/- 11 to 84 +/- 7 mL/min) and hepatic (94 +/- 11 to 67 +/- 8 mL/min) oxygen deliveries decreased (P < 0.05). At t = 300 min, the levosimendan group showed lower MPAP (39 +/- 3 vs 49 +/- 2 mm Hg, P = 0.025), lower SVR (2158 +/- 186 vs 3069 +/- 370 dyn x s x cm(-5), P = 0.052), and lower MAP (55 +/- 9 vs 87 +/- 9 mm Hg, P < 0.001) than the control group. In both groups, CO, portal vein, and hepatic arterial blood flows decreased (P < 0.001); the mean values for the levosimendan group at t = 300 min were 2.0 +/- 0.4 L/min, 390 +/- 83 mL/min, and 36 +/- 12 mL/min, respectively. SMA blood flow decreased only in the levosimendan group (432 +/- 40 to 320 +/- 78 mL/min, P < 0.001), whereas gut oxygen delivery decreased in the levosimendan (85 +/- 12 to 63 +/- 12 mL/min, P < 0.001) and in the control (83 +/- 6 to 59 +/- 3 mL/min, P = 0.03) groups., Conclusion: Levosimendan administered after the establishment of endotoxemic shock to pigs receiving moderate fluid resuscitation prevented further increases in MPAP and maintained a low SVR. There were, however, no improvements in CO, MAP decreased, and levosimendan neither prevented the development of circulatory shock nor improved hepatosplanchnic perfusion.

Background: We compared the association of levosimendan or dobutamine with norepinephrine for the maintenance of systemic and hepatosplanchnic perfusion during early endotoxemic shock., Methods: Twenty anesthetized pigs (26.8 +/- 0.5 kg) were instrumented with flow probes and catheters to monitor systemic and regional perfusion as described in our companion article in this issue of the journal. Two animals were excluded because of surgical complications. Oxygen consumption (VO(2)) was measured by indirect calorimetry. Starting 1 h after instrumentation, an endotoxin infusion (Escherichia coli lipopolysaccharide, 2 microg x kg(-1) x h(-1)) was administered for 300 min. Sixty minutes after the start of endotoxin, the animals were fluid resuscitated (20 mL/kg dextran 70); at 120 min, they were randomized into three groups of six animals each: levosimendan (25-50 microg x kg(-1) x h(-1)), dobutamine (10-20 microg x kg(-1) x min(-1)), and control. In the first two groups, norepinephrine (0.5-2 microg x kg(-1) x min(-1)) was added when mean arterial blood pressure (MAP) or= baseline. The data were divided into two subsets: before (0-120 min, all animals) and after (120-300 min, three groups) randomization, and analyzed by analysis of variance. P < 0.05 was considered significant., Results: At 120 min, cardiac output was 15% higher (P < 0.001), systemic vascular resistance was 30% lower (P < 0.001), and MAP decreased 12.5% (P = 0.004); blood flow in the hepatic artery, superior mesenteric artery, and portal vein had increased by 100% (P = 0.004), 60% (P < 0.001), and 20% (P < 0.001), respectively. Between 120 and 300 min, cardiac output and systemic oxygen delivery decreased 50% in control animals (P < 0.05), remained unchanged in the levosimendan group, and increased 60% with dobutamine (P = 0.05). MAP (P = 0.043) and VO(2) (P = 0.001) decreased 20% in the control group. Portal vein flow decreased in the control (50%) and levosimendan (30%) groups (P < 0.001) and was therefore higher in the dobutamine group (P = 0.003) at 300 min. Hepatic and gut oxygen deliveries decreased in the levosimendan (50%, and 30%, respectively, P < 0.001) and control groups (70% and 45%, respectively, P < 0.05); thus, regional oxygen deliveries were greater in the dobutamine group (P < 0.05). In this group, mixed venous and hepatic vein oxygen saturation were maintained; the latter variable was higher than in the other groups (P < 0.05). Although unchanged with dobutamine, arterial (P = 0.020), portal (P = 0.020), and hepatic vein (P = 0.034) lactate concentrations increased twofold with levosimendan., Conclusion: In volume-resuscitated endotoxemic pigs, the association of either levosimendan or dobutamine with norepinephrine preserved systemic blood flow, oxygen delivery, and VO(2). However, only dobutamine-norepinephrine maintained portal blood flow, which was associated with preservation of splanchnic and hepatic oxygen homeostasis and stable lactate concentrations.

Purpose of Review: To present recent experiences and studies on the pharmacologic profile of levosimendan in the context of surgery, anesthesia and critical care. Special emphasis is on the studies that could support the use of or create novel indications for levosimendan in these patients., Recent Findings: Several controlled studies now suggest that levosimendan is efficacious in improving hemodynamics in patients after cardiac surgery. Its use as an adjunct to catecholamines instead of phosphodiesterase inhibitors can be recommended in patients with postcardiotomy heart failure and cardiogenic shock. Prophylactic administration before cardiopulmonary bypass in patients with compromised ventricular function may also be rational because levosimendan facilitates weaning from cardiopulmonary bypass without inotropes with higher myocardial oxygen cost of inotropy. This mode of administration also seems to attenuate troponin release and spares treatment resources such as duration of postoperative ventilation and ICU stay. The reported experience in patients with noncardiac surgery is meager but previous results obtained from nonsurgical patients should be largely applicable. The use of levosimendan in treating septic myocardial depression or sepsis syndrome is a promising option but remains investigational for today., Summary: New practice advisories and proposals for indications to treat and prevent low-output syndrome in patients at risk are warranted for patients undergoing cardiac surgery with cardiopulmonary bypass. Levosimendan should also be considered as an adjunct drug for the treatment of cardiogenic shock. Further experience and controlled studies are needed to support the use of levosimendan for other perturbations in critical care and perioperative medicine.

We investigated the phenotypic impact of a number of uncommon amino acid substitutions at HIV-1 reverse transcriptase positions 103 and 138, which are not part of the etravirine resistance score and were found in combination with the high-impact mutation K101P. Etravirine phenotypic fold changes were 380-1400 for K101P + E138A/G/Q + K103N/S/T + V179I and 12-130 for K101P + (K103S +/- V179I) in the absence of E138A/G/Q. Although the effect of K103S is unclear, additional position 138 substitutions seem important for etravirine susceptibility.

Background: Emerging evidence indicates that an endogenous autocrine/paracrine system involving gamma-aminobutyric acid (GABA) is present in airways. GABAA channels, GABAB receptors, and the enzyme that synthesizes GABA have been identified in airway epithelium and smooth muscle. However, the endogenous ligand itself, GABA, has not been measured in airway tissues. The authors sought to demonstrate that GABA is released in response to contractile agonists and tonically contributes a prorelaxant component to contracted airway smooth muscle., Methods: The amount and cellular localization of GABA in upper guinea pig airways under resting and contracted tone was determined by high pressure liquid chromatography and immunohistochemistry, respectively. The contribution that endogenous GABA imparts on the maintenance of airway smooth muscle acetylcholine-induced contraction was assessed in intact guinea pig airway tracheal rings using selective GABAA antagonism (gabazine) under resting or acetylcholine-contracted conditions. The ability of an allosteric agent (propofol) to relax a substance P-induced relaxation in an endogenous GABA-dependent manner was assessed., Results: GABA levels increased and localized to airway smooth muscle after contractile stimuli in guinea pig upper airways. Acetylcholine-contracted guinea pig tracheal rings exhibited an increase in contracted force upon addition of the GABAA antagonist gabazine that was subsequently reversed by the addition of the GABAA agonist muscimol. Propofol dose-dependently relaxed a substance P contraction that was blocked by gabazine., Conclusion: These studies demonstrate that GABA is endogenously present and increases after contractile stimuli in guinea pig upper airways and that endogenous GABA contributes a tonic prorelaxant component in the maintenance of airway smooth muscle tone.

Levosimendan is a novel inodilator agent, which enhances myocardial performance without substantial changes in oxygen consumption. The combination of positive inotropic and vasodilator effects of levosimendan relates to its Ca-sensitizing and K channel opening effects. Levosimendan is one of the best documented pharmacological agents used in the management of acute heart failure syndromes. Interest in levosimendan has recently been renewed owing to its potential in supporting cardiac function in patients with ischemic heart disease and cardiogenic or septic shock. It has been also demonstrated that levosimendan can be used as a bridge therapy for the perioperative phase of cardiac surgery. The ability of levosimendan to improve myocardial function without substantially increasing oxygen consumption may appear paradoxical but is indeed possible via improved efficacy, not only with regard to the effects on the contractile apparatus of the cardiomyocytes but also when its composite hemodynamic effects are considered. The energy balance equation, therefore, should take into account the effect of levosimendan on all energy-consuming and energy-producing paths. Moreover, levosimendan-evoked KATP channel opening may possess favorable effects on mitochondrial adenosine triphosphate synthesis conferring cardioprotection during ischemic insults.