Fluid Overload and AKI After the Norwood Operation: The Correlation and Characterization of Routine Clinical Markers.

The purpose of this study was to determine the correlation of different methods of assessing fluid overload and determine which metrics are associated with development of acute kidney injury (AKI) in the period immediately following Norwood palliation. This was a retrospective single-center study of Norwood patients from January 2011 through January 2021. AKI was defined using the Kidney Disease Improving Global Outcomes (KDIGO). Patients were separated into two groups: those with AKI and those without. A logistic regression analysis was conducted with AKI at any point in the study period as the dependent variable and clinical and laboratory data as independent variables. Analysis was conducted as a stepwise regression. The coefficients from the logistic regression were then used to develop a cumulative AKI risk score. Spearman correlations were conducted to analyze the correlation of fluid markers. 116 patients were included, and 49 (42.4%) developed AKI. The duration of open chest, duration of mechanical ventilation, need for dialysis, need for extracorporeal membrane oxygenation, and inpatient mortality were associated with AKI (p ≤ 0.05). Stepwise logistic regression demonstrated the following significant independent associations AKI: age at Norwood in days (p < 0.01), blood urea nitrogen (p < 0.01), central venous pressure (p = 0.04), and renal oxygen extraction ratio (p < 0.01). The area under the receiver operating characteristic curve for the logistic regression was 0.74. The fluid markers had weak R-value. Urea, central venous pressure, and renal oxygen extraction ratio are associated with AKI after the Norwood operation. Common clinical metrics used to assess fluid overload are poorly correlated with each other for postoperative Norwood patients.

Use of Fenoldopam in Children with Congenital Heart Disease to Decrease Fluid Balance: A Retrospective, Descriptive Study and Insights into Predictors of Decreased Fluid Balance.

This retrospective study aimed to determine if fenoldopam is associated with a decrease in fluid balance and to define the factors that may promote this in children with a history of congenital heart disease at the cardiac intensive care unit (CICU). Patients cared from January 2014 to December 2018 in the CICU were reviewed, and those on fenoldopam infusion were identified. Patient cohort data included demographics, clinical information, laboratory results, hemodynamic and urine output measurements, and information regarding fenoldopam infusion were compared between those with and without decrease in fluid balance. Forty-six patients were identified. Patients received a starting dose of fenoldopam of 0.2 mcg/kg/h, a maximum dose of 0.3 mcg/kg/h, and duration of 64 hours. Over the 4-hour study period, statistically significant change was noted in systolic pressure (decrease of 5.4%; p < 0.001), diastolic pressure (decrease of 3.5%; p = 0.01), fluid balance, and urine output (decrease of 1.3%; p = 0.027). In the cohort, 34 patients (74%) had a decrease in fluid balance, 18 (39%) had an increase in urine output, and 25 (54%) had a decrease in fluid input after the initiation of fenoldopam. Patients that had a decrease in fluid balance tended to have a higher blood urea nitrogen level at the time of fenoldopam initiation. Fenoldopam was associated with decrease in fluid balance and fluid input, but not associated with an increase in urine output. The identification of factors that can decrease fluid balance may help identify those patients who can be benefited with this treatment.

Rhizoctonia solani Kühn Pathophysiology: Status and Prospects of Sheath Blight Disease Management in Rice.

Sheath blight caused by necrotrophic fungus Rhizoctonia solani Kühn is one of the most serious diseases of rice. Use of high yielding semi dwarf cultivars with dense planting and high dose of nitrogenous fertilizers accentuates the incidence of sheath blight in rice. Its diverse host range and ability to remain dormant under unfavorable conditions make the pathogen more difficult to manage. As there are no sources of complete resistance, management through chemical control has been the most adopted method for sheath blight management. In this review, we provide an up-to-date comprehensive description of host-pathogen interactions, various control measures such as cultural, chemical, and biological as well as utilizing host plant resistance. The section on utilizing host plant resistance includes identification of resistant sources, mapping QTLs and their validation, identification of candidate gene(s) and their introgression through marker-assisted selection. Advances and prospects of sheath blight management through biotechnological approaches such as overexpression of genes and gene silencing for transgenic development against R. solani are also discussed.

Inhibition of Complement Factor 3 in Geographic Atrophy with NGM621: Phase 1 Dose-Escalation Study Results.

PURPOSE: To evaluate the safety and tolerability of single and multiple intravitreal injections of NGM621 in patients with geographic atrophy (GA) and to characterize the pharmacokinetics and immunogenic potential. DESIGN: Multicenter, open-label, single- and multiple-dose phase 1 study. METHODS: Fifteen patients enrolled at 4 sites in the United States. Participants had GA secondary to age-related macular degeneration, lesion size ≥2.5 mm2, best-corrected visual acuity of 4 to 54 letters (20/80 to 20/800 Snellen equivalent) in the study eye, and no history of choroidal neovascularization in either eye. Patients who met eligibility criteria were treated in a single ascending-dose phase (2 mg, 7.5 mg, and 15 mg) or received 2 doses of NGM621 (15 mg) 4 weeks apart in the multidose phase and were monitored for 12 weeks (85 days). Assessments included adverse events, best-corrected visual acuity, low-luminance visual acuity, vital signs, clinical laboratory evaluations, GA lesion area as measured by fundus autofluorescence, spectral domain optical coherence tomography, and pharmacokinetic, immunogenicity, and pharmacodynamic assessments. RESULTS: All 15 participants completed the 12-week study. There were no serious adverse events, no drug-related adverse events, and no choroidal neovascularization developed in either eye. Mean visual acuity and GA lesion area appeared stable through week 12 for all cohorts. Pharmacokinetic analyses indicated that NGM621 serum exposures appeared to be dose proportional, and no antidrug antibodies were identified at any of the evaluated time points. CONCLUSIONS: In this small, open-labeled, 12-week phase 1 study, NGM621 was safe and tolerable when administered intravitreally up to 15 mg..

Antibody semorinemab reduces tau pathology in a transgenic mouse model and engages tau in patients with Alzheimer's disease.

Tau has become an attractive alternative target for passive immunotherapy efforts for Alzheimer's disease (AD). The anatomical distribution and extent of tau pathology correlate with disease course and severity better than other disease markers to date. We describe here the generation, preclinical characterization, and phase 1 clinical characterization of semorinemab, a humanized anti-tau monoclonal antibody with an immunoglobulin G4 (igG4) isotype backbone. Semorinemab binds all six human tau isoforms and protects neurons against tau oligomer neurotoxicity in cocultures of neurons and microglia. In addition, when administered intraperitoneally once weekly for 13 weeks, murine versions of semorinemab reduced the accumulation of tau pathology in a transgenic mouse model of tauopathy, independent of antibody effector function status. Semorinemab also showed clear evidence of target engagement in vivo, with increases in systemic tau concentrations observed in tau transgenic mice, nonhuman primates, and humans. Higher concentrations of systemic tau were observed after dosing in AD participants compared to healthy control participants. No concerning safety signals were observed in the phase 1 clinical trial at single doses up to 16,800 mg and multiple doses totaling 33,600 mg in a month.

Effect of Overpressure on Acoustic Emissions and Treated Tissue Histology in ex Vivo Bulk Ultrasound Ablation.

Bulk ultrasound ablation is a thermal therapy approach in which tissue is heated by unfocused or weakly focused sonication (average intensities on the order of 100 W/cm2) to achieve coagulative necrosis within a few minutes exposure time. Assessing the role of bubble activity, including acoustic cavitation and tissue vaporization, in bulk ultrasound ablation may help in making bulk ultrasound ablation safer and more effective for clinical applications. Here, two series of ex vivo ablation trials were conducted to investigate the role of bubble activity and tissue vaporization in bulk ultrasound ablation. Fresh bovine liver tissue was ablated with unfocused, continuous-wave ultrasound using ultrasound image-ablate arrays sonicating at 31 W/cm2 (0.9 MPa amplitude) for either 20 min at a frequency of 3.1 MHz or 10 min at 4.8 MHz. Tissue specimens were maintained at a static overpressure of either 0.52 or 1.2 MPa to suppress bubble activity and tissue vaporization or at atmospheric pressure for control groups. A passive cavitation detector was used to record subharmonic (1.55 or 2.4 MHz), broadband (1.2-1.5 MHz) and low-frequency (5-20 kHz) acoustic emissions. Treated tissue was stained with 2% triphenyl tetrazolium chloride to evaluate thermal lesion dimensions. Subharmonic emissions were significantly reduced in overpressure groups compared with control groups. Correlations observed between acoustic emissions and lesion dimensions were significant and positive for the 3.1-MHz series, but significant and negative for the 4.8-MHz series. The results indicate that for bulk ultrasound ablation, where both acoustic cavitation and tissue vaporization are possible, bubble activity can enhance ablation in the absence of tissue vaporization, but can reduce thermal lesion dimensions in the presence of vaporization.

Two infants with bilateral renal agenesis who were bridged by chronic peritoneal dialysis to kidney transplantation.

Bilateral renal agenesis is associated with severe oligohydramnios and was considered incompatible with postnatal life due to severe pulmonary hypoplasia. The use of renal replacement therapy was limited by significant morbidity and mortality associated with dialysis in very young infants with major pulmonary pathology. In the United States, there is a tremendous controversy about whether or not the use of prenatal amniotic fluid infusions provides a benefit to fetuses with bilateral renal agenesis. One of the critical issues identified is that there are, as yet, no children reported who had achieved long-term survival. Previous reports all indicated these children died shortly after birth or after unsuccessful peritoneal dialysis. We present two infants with a prenatal diagnosis of bilateral renal agenesis whose mothers elected to undergo prenatal amnioinfusions. One was born at 28 weeks with a birthweight of 1230 g and the other born at 34 weeks with a birthweight of 1940 g. We present the details of both cases, with initial management on chronic peritoneal dialysis, which started shortly after birth, as a bridge to living related kidney transplants.

Pharmacokinetics and safety of vismodegib in patients with advanced solid malignancies and hepatic impairment.

PURPOSE: Vismodegib is a Hedgehog pathway inhibitor approved for the treatment of advanced basal cell carcinoma. Currently, the pharmacokinetics (PK) and safety of vismodegib in patients with hepatic dysfunction are unknown and are the objective of this study. METHODS: Patients with advanced solid malignancies and hepatic impairment were enrolled into one of four cohorts: normal [bilirubin (bili) < upper limit of normal (ULN)], mild (ULN < bili ≤ 1.5 × ULN), moderate (1.5 × ULN < bili ≤ 3×ULN), and severe (3 × ULN < bili < 10 × ULN) dysfunction. Patients received oral vismodegib 150 mg daily. Plasma PK samples on days 1, 3, 5, and 8 were collected. Vismodegib therapy was continued until disease progression, intolerable toxicity, or withdrawal of consent. RESULTS: Thirty-one patients were accrued: nine normal, eight mild, eight moderate, and six severe. Four patients experienced dose-limiting toxicity of hyperbilirubinemia on study: one in the moderate cohort and three in the severe cohort. Six patients died within 30 days after the last dose of vismodegib. All deaths were attributed to disease progression. Observed maximal and average steady-state concentrations and AUC of vismodegib at steady state (day 8) were similar across cohorts. Average AAG concentrations in patients with hepatic impairment were comparable to those of patients with normal hepatic function. CONCLUSIONS: Hepatic impairment does not appear to impact vismodegib PK, and therefore, dose adjustment is not necessary in this special population. The study was influenced by the high number of patients with hepatocellular carcinoma with advanced cirrhosis; rendering it difficult to draw any causal relationships between vismodegib exposure and the serious adverse events.

Effect of food on the oral bioavailability of the angiotensin receptor - neprilysin inhibitor sacubitril/valsartan (LCZ696) in healthy subjects
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OBJECTIVE: Sacubitril/valsartan (LCZ696) provides a novel therapeutic approach of neurohormonal modulation in heart failure via simultaneous inhibition of neprilysin and blockade of the angiotensin II type-1 receptor. This study was conducted to evaluate the effect of food on the oral bioavailability of LCZ696 analytes. MATERIALS AND METHODS: This was an open-label, randomized, 3-period crossover study in healthy subjects. Eligible subjects (N = 36) were randomized to 6 treatment sequences, each comprising 3 treatment periods during which subjects received a single oral dose of 400 mg LCZ696 under fasting condition and following a low- and high-fat meal. RESULTS: Following administration of LCZ696 after low- and high-fat meals, the mean Cmax of sacubitril and sacubitrilat (the active neprilysin inhibitor) decreased by 42 - 54% and 19 - 28%, respectively, while the tmax values increased. However, systemic exposure (AUCinf and AUClast) of sacubitril was slightly decreased (by 16% with low-fat meal) and that of sacubitrilat was unchanged in the presence of food. For valsartan, the Cmax decreased by ~ 40% when LCZ696 was administered after low- and high-fat meals. The systemic exposure of valsartan decreased by ~ 33% with a low-fat meal; however, it was unchanged with a high-fat meal. LCZ696 was generally safe and well tolerated in healthy subjects when administered under fasting or fed condition. CONCLUSION: Overall, administration of LCZ696 with meals decreased the rate and extent of absorption of sacubitril with little impact on the systemic exposure to sacubitrilat, its active metabolite. The systemic exposure to valsartan was decreased in the presence of food.
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A clinical drug-drug interaction study to evaluate the effect of a proton-pump inhibitor, a combined P-glycoprotein/cytochrome 450 enzyme (CYP)3A4 inhibitor, and a CYP2C9 inhibitor on the pharmacokinetics of vismodegib.

PURPOSE: The Hedgehog pathway inhibitor vismodegib exhibits pH-dependent solubility, and in vitro studies have shown that vismodegib is a substrate of P-glycoprotein (P-gp) and is metabolized by cytochrome P450 (CYP) 2C9 and 3A4. The objective of this four-arm parallel study in healthy subjects was to evaluate the effect of the proton-pump inhibitor rabeprazole, the P-gp/CYP3A4 inhibitor itraconazole, and the CYP2C9 and 3A4 inhibitor fluconazole on vismodegib steady-state pharmacokinetics. METHODS: Cohorts included a control arm (n = 22), in which vismodegib 150 mg was administered once daily (QD) for 7 days, and 3 arms in which vismodegib was co-administered QD for 7 days with rabeprazole 20 mg (including a 4-day lead-in; n = 24); itraconazole 200 mg (n = 22); or fluconazole 400 mg (n = 22). RESULTS: Area under the vismodegib concentration-time curve from zero to 24 h (AUC0-24h) at steady state was lower with concomitant rabeprazole administration relative to vismodegib alone [geometric mean ratio (GMR), 86.2 (associated 90 % confidence interval [CI], 76.1, 97.7)]. There was no effect of itraconazole on steady-state exposure of vismodegib [GMR, 96.4 (90 % CI 84.9, 109.6)]. Co-administration with fluconazole increased vismodegib steady-state AUC0-24h [GMR, 130.9 (90 % CI 115.2, 148.7)]. Co-administration of rabeprazole, itraconazole, and fluconazole had similar effects on the exposure of unbound vismodegib and total vismodegib. CONCLUSION: The results of this study suggest that vismodegib can be administered with acid-reducing agents and P-gp and CYP inhibitors without the risk of a clinically meaningful pharmacokinetic drug-drug interaction. CLINICALTRIALS. GOV IDENTIFIER: NCT01772290.

Single therapeutic and supratherapeutic doses of sacubitril/valsartan (LCZ696) do not affect cardiac repolarization.

PURPOSE: Sacubitril/valsartan (LCZ696) is a first-in-class angiotensin receptor neprilysin inhibitor (ARNI) indicated to reduce the risk of cardiovascular death and hospitalization for heart failure in patients with chronic heart failure (NYHA class II-IV) and reduced ejection fraction. This study was aimed to evaluate the effect of single oral therapeutic (400 mg) and supratherapeutic (1200 mg) doses of LCZ696 on cardiac repolarization. METHOD: This randomized double-blind crossover study in healthy male subjects compared the effect of therapeutic and supratherapeutic doses of LCZ696 with placebo and moxifloxacin 400 mg (open-label treatment) as positive control. The primary assessment was mean baseline- and placebo-corrected QTcF (∆∆QTcF; Fridericia correction). Additional assessments included the ∆∆QTcB (Bazett's correction), PR interval, QRS duration, heart rate (HR), LCZ696 pharmacokinetics, pharmacokinetic/pharmacodynamic relationships, and safety. RESULTS: Of the 84 subjects enrolled, 81 completed the study. The maximum upper bound of the two-sided 90 % confidence interval for ∆∆QTcF for LCZ696 400 mg and 1200 mg were <10 ms, and assay sensitivity was confirmed with moxifloxacin. No relevant treatment-emergent changes were observed in any of the ECG-derived parameters with LCZ696 or placebo, and the incidence of adverse events was comparable among the treatment groups. CONCLUSION: Single therapeutic and supratherapeutic doses of LCZ696 did not affect cardiac repolarization as defined by the E14 ICH guidelines.

Disposition and metabolism of [(14)C] Sacubitril/Valsartan (formerly LCZ696) an angiotensin receptor neprilysin inhibitor, in healthy subjects.

1. Sacubitril/valsartan (LCZ696) is an angiotensin receptor neprilysin inhibitor (ARNI) providing simultaneous inhibition of neprilysin (neutral endopeptidase 24.11; NEP) and blockade of the angiotensin II type-1 (AT1) receptor. 2. Following oral administration, [(14)C]LCZ696 delivers systemic exposure to valsartan and AHU377 (sacubitril), which is rapidly metabolized to LBQ657 (M1), the biologically active neprilysin inhibitor. Peak sacubitril plasma concentrations were reached within 0.5-1 h. The mean terminal half-lives of sacubitril, LBQ657 and valsartan were ∼1.3, ∼12 and ∼21 h, respectively. 3. Renal excretion was the dominant route of elimination of radioactivity in human. Urine accounted for 51.7-67.8% and feces for 36.9 to 48.3 % of the total radioactivity. The majority of the drug was excreted as the active metabolite LBQ657 in urine and feces, total accounting for ∼85.5% of the total dose. 4. Based upon in vitro studies, the potential for LCZ696 to inhibit or induce cytochrome P450 (CYP) enzymes and cause CYP-mediated drug interactions clinically was found to be low.

Pharmacodynamic and Pharmacokinetic Profiles of Sacubitril/Valsartan (LCZ696) in Patients with Heart Failure and Reduced Ejection Fraction.

AIMS: Concomitant renin-angiotensin-aldosterone system blockade and natriuretic peptide system enhancement may provide unique therapeutic benefits to patients with heart failure and reduced ejection fraction (HFrEF). This study assessed the pharmacodynamics and pharmacokinetics of LCZ696 in patients with HFrEF. METHODS: This was an open-label, noncontrolled single-sequence study. After a 24-h run-in period, patients (n = 30) with HFrEF (EF ≤ 40%; NYHA class II-IV) received LCZ696 100 mg twice daily (bid) for 7 days and 200 mg bid for 14 days, along with standard treatment for heart failure (HF) (except angiotensin-converting enzyme inhibitors [ACEIs] or angiotensin receptor blockers [ARBs]). RESULTS: On Day 21, significant increases were observed in the plasma biomarkers indicative of neprilysin and RAAS inhibition (ratio-to-baseline: cyclic guanosine monophosphate [cGMP], 1.38; renin concentration and activity, 3.50 and 2.27, respectively; all, P < 0.05). Plasma NT-proBNP levels significantly decreased at all the time points on Days 7 and 21; plasma aldosterone and endothelin-1 levels significantly decreased on Day 21 (all, P < 0.05). Following administration of LCZ696, the Cmax of sacubitril (neprilysin inhibitor prodrug), LBQ657 (active neprilysin inhibitor), and valsartan were reached within 0.5, 2.5, and 2 h. Between 100- and 200-mg doses, the Cmax and AUC0-12 h for sacubitril and LBQ657 were approximately dose-proportional while that of valsartan was less than dose-proportional. CONCLUSIONS: Treatment with LCZ696 for 21 days was well tolerated and resulted in plasma biomarker changes indicative of neprilysin and RAAS inhibition in patients with HF. The pharmacokinetic exposure of the LCZ696 analytes in patients with HF observed in this study is comparable to that observed in the pivotal Phase III study.

Effects of age and sex on the pharmacokinetics of LCZ696, an angiotensin receptor neprilysin inhibitor.

LCZ696, a novel angiotensin receptor neprilysin inhibitor, is in development for the treatment of heart failure. Administration of LCZ696 results in systemic exposure to sacubitril (inactive prodrug of LBQ657), LBQ657 (neprilysin inhibitor), and valsartan (angiotensin II receptor blocker). We investigated the potential effects of age and sex on the pharmacokinetics of LCZ696 analytes (LBQ657 and valsartan) in an open-label, single oral dose (400 mg), parallel-group study in healthy subjects. Among 36 enrolled subjects, there were 19 male and 17 female subjects; 18 subjects were 18-45 years old (young), and 18 subjects were 65 years of age or older (elderly). Compared with young subjects, the AUCinf and T1/2 for LBQ657 were 42% and 30% greater, respectively, in elderly subjects. The Cmax for LBQ657 was similar between age groups. The AUCinf, Cmax, and T1/2 for valsartan were 30%, 24% greater, and 3.35 hours longer, respectively, in the elderly when compared with young subjects. All pharmacokinetic parameters of LCZ696 analytes (LBQ657 and valsartan) were similar between male and female subjects, indicating no effect on the pharmacokinetics of LCZ696 analytes based on sex. Considering the magnitude of change and its clinical significance, dose adjustment based on age or sex is not considered necessary.

In vivo thermal ablation monitoring using ultrasound echo decorrelation imaging.

Previous work indicated that ultrasound echo decorrelation imaging can track and quantify changes in echo signals to predict thermal damage during in vitro radiofrequency ablation (RFA). In the in vivo studies reported here, the feasibility of using echo decorrelation imaging as a treatment monitoring tool was assessed. RFA was performed on normal swine liver (N = 5), and ultrasound ablation using image-ablate arrays was performed on rabbit liver implanted with VX2 tumors (N = 2). Echo decorrelation and integrated backscatter were computed from Hilbert transformed pulse-echo data acquired during RFA and ultrasound ablation treatments. Receiver operating characteristic (ROC) curves were employed to assess the ability of echo decorrelation imaging and integrated backscatter to predict ablation. Area under the ROC curves (AUROC) was determined for RFA and ultrasound ablation using echo decorrelation imaging. Ablation was predicted more accurately using echo decorrelation imaging (AUROC = 0.832 and 0.776 for RFA and ultrasound ablation, respectively) than using integrated backscatter (AUROC = 0.734 and 0.494).

Treatment of rabbit liver cancer in vivo using miniaturized image-ablate ultrasound arrays.

In the preclinical studies reported here, VX2 cancer within rabbit liver has been treated by bulk ultrasound ablation employing miniaturized image-ablate arrays. Array probes were constructed with 32 elements in a 2.3 × 20 mm(2) aperture, packaged within a 3.1 mm stainless steel tube with a cooling and coupling balloon for in vivo use. The probes were measured capable of 50% fractional bandwidth for pulse-echo imaging (center frequency 4.4 MHz) with >110 W/cm(2) surface intensity available at sonication frequencies 3.5 and 4.8 MHz. B-scan imaging performance of the arrays was measured to be comparable to larger diagnostic linear arrays, although nearfield image quality was reduced by ringdown artifacts. A series of in vivo ablation procedures was performed using an unfocused 32-element aperture firing at 4.8 MHz with exposure durations 20-70.5 s and in situ spatial average, temporal average intensities 22.4-38.5 W/cm(2). Ablation of a complete tumor cross-section was confirmed by vital staining in seven of 12 exposures, with four exposures ablating an additional margin >1 mm beyond the tumor in all directions. Analysis suggests a threshold ablation effect, with complete ablation of tumor cross-sections for exposures with delivery of >838 J acoustic energy. The results show feasibility for in vivo liver cancer ablation using miniaturized image-ablate arrays suitable for interstitial deployment.

Endophilin drives the fast mode of vesicle retrieval in a ribbon synapse.

Compensatory endocytosis of exocytosed membrane and recycling of synaptic vesicle components is essential for sustained synaptic transmission at nerve terminals. At the ribbon-type synapse of retinal bipolar cells, manipulations expected to inhibit the interactions of the clathrin adaptor protein complex (AP2) affect only the slow phase of endocytosis (τ = 10-15 s), leading to the conclusion that fast endocytosis (τ = 1-2 s) occurs by a mechanism that differs from the classical pathway of clathrin-coated vesicle retrieval from the plasma membrane. Here we investigate the role of endophilin in endocytosis at this ribbon synapse. Endophilin A1 is a synaptically enriched N-BAR domain-containing protein, suggested to function in clathrin-mediated endocytosis. Internal dialysis of the synaptic terminal with dominant-negative endophilin A1 lacking its linker and Src homology 3 (SH3) domain inhibited the fast mode of endocytosis, while slow endocytosis continued. Dialysis of a peptide that binds endophilin SH3 domain also decreased fast retrieval. Electron microscopy indicated that fast endocytosis occurred by retrieval of small vesicles in most instances. These results indicate that endophilin is involved in fast retrieval of synaptic vesicles occurring by a mechanism that can be distinguished from the classical pathway involving clathrin-AP2 interactions.

Peripheral augmentation index and vascular inflammation in autosomal dominant polycystic kidney disease.

BACKGROUND: Cardiovascular disease is the leading cause of premature mortality in autosomal dominant polycystic kidney disease (ADPKD). We examined peripheral augmentation index (AIx) as a measure of systemic vascular function and circulating markers of vascular inflammation in patients with ADPKD. METHODS: Fifty-two ADPKD patients with hypertension and estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2), 50 ADPKD patients with hypertension and eGFR ≥ 60 mL/min/1.73 m(2), 42 normotensive ADPKD patients with eGFR ≥ 60 mL/min/1.73 m(2) and 51 normotensive healthy controls were enrolled in this study. AIx was measured from peripheral artery tone recordings using finger plethysmography. Serum levels of soluble intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule-1, P-selectin, E-selectin, soluble Fas (sFas) and Fas ligand (FasL) were measured as markers of vascular inflammation. RESULTS: AIx was higher in all three patient groups with ADPKD compared to healthy controls (P < 0.05). AIx was similar between the normotensive ADPKD patients with eGFR ≥ 60 mL/min/1.73 m(2) and hypertensive ADPKD patients with eGFR < 60 mL/min/1.73 m(2) (P > 0.05). ICAM, P-selectin, E-selectin and sFas were higher and FasL lower in all ADPKD groups compared to controls (P < 0.05). ICAM, P-selectin and E-selectin were similar between the normotensive ADPKD patients with eGFR ≥ 60 mL/min/1.73 m(2) and hypertensive ADPKD patients with eGFR < 60 mL/min/1.73 m(2) (P > 0.05). According to multiple regression analysis, predictors of AIx in ADPKD included age, height, heart rate and mean arterial pressure (P < 0.05). Vascular inflammatory markers were not predictors of AIx in ADPKD. CONCLUSIONS: Systemic vascular dysfunction, manifesting as an increase in AIx and vascular inflammation is evident in young normotensive ADPKD patients with preserved renal function. Vascular inflammation is not associated with elevated AIx in ADPKD.

Inflammation, oxidative stress, and insulin resistance in polycystic kidney disease.

BACKGROUND AND OBJECTIVES: Most deaths in autosomal dominant polycystic kidney disease (ADPKD) are attributable to cardiovascular disease (CVD). We examined novel CVD biomarkers in different stages of ADPKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We recruited 50 hypertensive subjects with ADPKD with estimated GFR (eGFR) of >60 ml/min per 1.73 m(2); 52 hypertensive subjects with ADPKD with eGFR of 25 to 60 ml/min per 1.73 m(2); 42 normotensive subjects with ADPKD and eGFR of >60 ml/min per 1.73 m(2); and 50 healthy controls. We assayed serum C-reactive protein and IL-6 as markers of inflammation; plasma 8-epi-prostaglandin F(2α (8-epi-PGF2α)) and superoxide dismutase (SOD) as markers of oxidative stress; and homeostasis model assessment (HOMA) as a measure of insulin resistance. RESULTS: The hypertensive ADPKD eGFR of 25 to 60 group had higher levels of C-reactive protein and IL-6 than controls, normotensive ADPKD with eGFR of >60, and hypertensive ADPKD with eGFR of >60. The normotensive ADPKD eGFR >60, hypertensive ADPKD eGFR >60, and hypertensive ADPKD eGFR 25 to 60 groups had higher 8-epi-PGF(2α) and lower SOD than controls, with no difference between the ADPKD groups. There was no difference in HOMA levels between any of the groups. Adjustment for age, race, gender, and body mass index did not alter these relationships. CONCLUSIONS: Inflammation and oxidative stress are evident early in ADPKD even with preserved kidney function. Inflammation exhibits a graded relationship with levels of kidney function, whereas oxidative stress demonstrates a threshold effect. These pathways may be therapeutic targets for CVD risk mitigation.

Pharmacokinetics and pharmacodynamics of LCZ696, a novel dual-acting angiotensin receptor-neprilysin inhibitor (ARNi).

Angiotensin receptor blockade and neprilysin (NEP) inhibition together offer potential benefits for the treatment of hypertension and heart failure. LCZ696 is a novel single molecule comprising molecular moieties of valsartan and NEP inhibitor prodrug AHU377 (1:1 ratio). Oral administration of LCZ696 caused dose-dependent increases in atrial natriuretic peptide immunoreactivity (due to NEP inhibition) in Sprague-Dawley rats and provided sustained, dose-dependent blood pressure reductions in hypertensive double-transgenic rats. In healthy participants, a randomized, double-blind, placebo-controlled study (n = 80) of single-dose (200-1200 mg) and multiple-dose (50-900 mg once daily for 14 days) oral administration of LCZ696 showed that peak plasma concentrations were reached rapidly for valsartan (1.6-4.9 hours), AHU377 (0.5-1.1 hours), and its active moiety, LBQ657 (1.8-3.5 hours). LCZ696 treatment was associated with increases in plasma cGMP, renin concentration and activity, and angiotensin II, providing evidence for NEP inhibition and angiotensin receptor blockade. In a randomized, open-label crossover study in healthy participants (n = 56), oral LCZ696 400 mg and valsartan 320 mg were shown to provide similar exposure to valsartan (geometric mean ratio [90% confidence interval]: AUC(0-infinity) 0.90 [0.82-0.99]). LCZ696 was safe and well tolerated. These data support further clinical development of LCZ696, a novel, orally bioavailable, dual-acting angiotensin receptor-NEP inhibitor (ARNi) for hypertension and heart failure.