Isolated Heart Function after Ischemia and Reperfusion in Sucrose-Fed Rats: Influence of Gender and Treatment

Sucrose-fed rats (HTG) develop hypertension, hypertriglyceridemia, and other features of the metabolic syndrome. This condition, nowadays a world epidemic, is more prevalent in males and increases the risk of cardiovascular diseases. Weanling male and female rats were given either tap water in control (C) or 30% sucrose solution in HTG groups and commercial rat chow for 3, 5, or 8 months. We studied possible variations in cardiac function, due to gender and length of treatment, in isolated heart after ischemia-reperfusion, since an impaired performance may be more easily detected under stress. Together, sucrose treatment and age affected all cardiac variables. Gender had significant effect on coronary vascular resistance and postischemic levels of the enzyme CK-MB; the percentages of retained cardiac enzymes after ischemia were higher in C and HTG females. C and HTG males had a higher incidence of arrhythmias than females, but only HTG males suffered lethal ventricular fibrillation.     

Enhanced wound vascularization using a dsASCs seeded FPEG scaffold

The bioengineering of autologous vascular networks is of great importance in wound healing. Adipose-derived stem cells (ASCs) are of interest due to their ability to differentiate toward various cell types, including vascular. We hypothesized that adult human ASCs embedded in a three-dimensional PEG-fibrin (FPEG) gel have the ability to modulate vascularization of a healing wound. Initial in vitro characterization of ASCs isolated from discarded burn skin samples (dsASCs) and embedded in FPEG gels indicated they could express such pericyte/smooth muscle cell markers as α-smooth muscle actin, platelet-derived growth factor receptor-β, NG2 proteoglycan, and angiopoietin-1, suggesting that these cells could potentially be involved in a supportive cell role (i.e., pericyte/mural cell) for blood vessels. Using a rat skin excision model, wounds treated with dsASCs-FPEG gels showed earlier collagen deposition and wound remodeling compared to vehicle FPEG treated wounds. Furthermore, the dsASCs-seeded gels increased the number of vessels in the wound per square millimeter by day 16 (~66.7 vs. ~36.9/mm²) in these same studies. dsASCs may support this increase in vascularization through their trophic contribution of vascular endothelial growth factor, as determined by in vitro analysis of mRNA and the protein levels. Immunohistochemistry showed that dsASCs were localized to the surrounding regions of large blood-perfused vessels. Human dsASCs may play a supportive role in the formation of vascular structures in the healing wound through direct mechanisms as well as indirect trophic effects. The merging of autologous grafts or bioengineered composites with the host’s vasculature is critical, and the use of autologous dsASCs in these procedures may prove to be therapeutic.     

Targeted alteration of dietary n-3 and n-6 fatty acids for the treatment of chronic headaches: A randomized trial

Omega-3 and n-6 fatty acids are biosynthetic precursors to lipid mediators with antinociceptive and pronociceptive properties. We conducted a randomized, single-blinded, parallel-group clinical trial to assess clinical and biochemical effects of targeted alteration in dietary n-3 and n-6 fatty acids for treatment of chronic headaches. After a 4-week preintervention phase, ambulatory patients with chronic daily headache undergoing usual care were randomized to 1 of 2 intensive, food-based 12-week dietary interventions: a high n-3 plus low n-6 (H3-L6) intervention, or a low n-6 (L6) intervention. Clinical outcomes included the Headache Impact Test (HIT-6, primary clinical outcome), Headache Days per month, and Headache Hours per day. Biochemical outcomes included the erythrocyte n-6 in highly unsaturated fatty acids (HUFA) score (primary biochemical outcome) and bioactive n-3 and n-6 derivatives. Fifty-six of 67 patients completed the intervention. Both groups achieved targeted intakes of n-3 and n-6 fatty acids. In intention-to-treat analysis, the H3-L6 intervention produced significantly greater improvement in the HIT-6 score (−7.5 vs −2.1; P < 0.001) and the number of Headache Days per month (−8.8 vs −4.0; P = 0.02), compared to the L6 group. The H3-L6 intervention also produced significantly greater reductions in Headache Hours per day (−4.6 vs −1.2; P = 0.01) and the n-6 in HUFA score (−21.0 vs −4.0%; P < 0.001), and greater increases in antinociceptive n-3 pathway markers 18-hydroxy-eicosapentaenoic acid (+118.4 vs +61.1%; P < 0.001) and 17-hydroxy-docosahexaenoic acid (+170.2 vs +27.2; P < 0.001). A dietary intervention increasing n-3 and reducing n-6 fatty acids reduced headache pain, altered antinociceptive lipid mediators, and improved quality-of-life in this population.     

Diagnostic problems in visceral heterotaxia]

Due to the lack of uniformity in the criteria for formulating the diagnosis of the syndrome of heterotaxy, 12 cases with this abnormality were reviewed. The patients were selected on the following basis: symmetrical liver, changeable P waves in consecutive electrocardiograms, bronchial isomerism, hematological disturbances, anomalous relationship of the inferior vena cava and abdominal aorta, anomalous systemic and pulmonary venous drainage and complex cardiac malformations. The most frequent findings were: symmetrical liver, changeable P waves, anomalous systemic venous return, anomalies of the atrio-ventricular valves, particularly atrioventricular canal, aorto-cava juxtaposition, single atrium, anomalous pulmonary venous return, transposition of the great arteries and pulmonary stenosis. Less frequent anomalies were: atrial and ventricular septal defects, atrial isomerism, truncus arteriosus and partial distortion of the great arteries. The hematological disturbances as well as the radioisotope scanning of the liver and the spleen were of little help. Suggestions are given for the diagnosis of the syndrome and for the evaluation of present diagnostic procedures making necessary to use the data gathered with more precision.     

Número de pacientes candidatos a recibir inhibidores de la PCSK9 según datos de 2,5 millones de participantes de la práctica clínica real

Introduction and objectives

PCSK9 inhibitors (PCSK9i) are safe and effective lipid-lowering drugs. Their main limitation is their high cost. The aim of this study was to estimate the number of patients eligible for treatment with PCSK9i according to distinct published criteria.

Phase I studies of the safety,tolerability, pharmacokinetics,and pharmacodynamics of DS‐1211, a tissue‐nonspecific alkaline phosphatase inhibitor

Tissue‐nonspecific alkaline phosphatase (TNAP) hydrolyzes and inactivates inorganic pyrophosphate (PPi), a potent inhibitor of calcification; therefore, TNAP inhibition is a potential target to treat ectopic calcification. These two first‐in‐human studies evaluated safety, tolerability, pharmacokinetics (PKs), and pharmacodynamics (PDs) of single (SAD) and multiple‐ascending doses (MAD) of DS‐1211, a TNAP inhibitor. Healthy adults were randomized 6:2 to DS‐1211 or placebo, eight subjects per dose cohort. SAD study subjects received one dose of DS‐1211 (range, 3–3000 mg) or placebo, whereas MAD study subjects received DS‐1211 (range, 10–300 mg) once daily, 150 mg twice daily (b.i.d.), or placebo for 10 days. Primary end points were safety and tolerability. PK and PD assessments included plasma concentrations of DS‐1211, alkaline phosphatase (ALP) activity, and TNAP substrates (PPi, pyridoxal 5′‐phosphate [PLP], and phosphoethanolamine [PEA]). A total of 56 (DS‐1211: n = 42; placebo: n = 14) and 40 (DS‐1211: n = 30; placebo: n = 10) subjects enrolled in the SAD and MAD studies, respectively. In both studies, adverse events were mild or moderate and did not increase with dose. PKs of DS‐1211 were linear up to 100 mg administered as a single dose and 150 mg b.i.d. administered as a multiple‐dose regimen. In multiple dosing, there was minimal accumulation of DS‐1211. Increased DS‐1211 exposure correlated with dose‐dependent ALP inhibition and concomitant increases in PPi, PLP, and PEA. In two phase I studies, DS‐1211 appeared safe and well‐tolerated. Post‐treatment PD assessments were consistent with exposure‐dependent TNAP inhibition. These data support further evaluation of DS‐1211 for ectopic calcification diseases.

Study Highlights

• WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

In preclinical studies, successful inhibition of tissue‐nonspecific alkaline phosphatase (TNAP) decreased soft‐tissue calcification. However, TNAP inhibition is untested in humans, and the safety and pharmacological effects are unknown.

• WHAT QUESTION DID THIS STUDY ADDRESS?

What are the safety, tolerability, pharmacokinetic (PK), and pharmacodynamic (PD) effects of TNAP‐specific inhibitor DS‐1211?

• WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

TNAP inhibition mediated by orally administered DS‐1211 appears to be safe and well‐tolerated in humans. The PD effects of DS‐1211 on alkaline phosphatase, inorganic pyrophosphate, pyridoxal 5′‐phosphate, and phosphoethanolamine suggest it can inhibit TNAP in humans. This is the first clinical trial with a TNAP‐specific inhibitor; its safety over 10 days and PK‐dependent profiles of TNAP inhibition were established.

• HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?

Ectopic calcification lacks a direct and safe treatment. TNAP inhibition with DS‐1211 may provide a novel targeted therapy for excess soft‐tissue calcification.     

Lower femoral neck bone mineral density in prepubertal former preterm girls.

The purpose of this case-control study was to determine bone mineral content and areal bone mineral density at various skeletal sites in former preterm girls, aged 7-9 years, and to compare these data with age-matched term controls. Subjects included 25 white, prepubertal, former preterm girls (gestational age 30.8 +/- 0.3 weeks, birthweight 1461 +/- 56 g [mean +/- SEM]). Controls included 50 healthy, white, prepubertal girls born at term and matched for age (two controls per case). Measurements included anthropometric variables, calcium intake according to a food-frequency questionnaire, bone mineral content (BMC; grams), and areal bone mineral density (aBMD; grams per square centimeter), using dual-energy X-ray absorptiometry (DXA) at six skeletal sites. Thirteen preterm girls and 13 age-matched term controls were reassessed 1 year after the first DXA measurement. The former preterm girls were similar to controls in terms of age and height, but were lighter (24.6 +/- 0.6 vs. 27.0 +/- 0.6 kg, p = 0.02). They also reported a higher median calcium intake (1058 vs. 759 mg/day, p = 0.004). aBMD was lower in former preterms compared with controls at the level of the radial metaphysis (0.283 +/- 0.006 vs. 0.298 +/- 0.004, p = 0.04), femoral neck (0.593 +/- 0.011 vs. 0.638 +/- 0.010, p = 0.007), and total hip (0.596 +/- 0.012 vs. 0.640 +/- 0.010, p = 0.007), but was similar between the two groups at the radial diaphysis (0.437 +/- 0.004 vs. 0.436 +/- 0.004) and femoral diaphysis (1.026 +/- 0.015 vs. 1.030 +/- 0.011). Femoral neck aBMD remained lower compared with controls in the subgroup of preterm girls reassessed after 1 year (0.608 +/- 0.017 vs. 0.672 +/- 0.020, p = 0.02). In random effects models for longitudinal data, taking into account the effects of age, weight, and height on aBMD (dependent variable), femoral neck aBMD remained lower in former preterms (p < 0.001). Prepubertal former preterm girls showed growth recovery, but had lower aBMD at the hip and radial metaphysis than age-matched term controls, despite spontaneously higher calcium intake. Preterm girls had similar aBMD results compared with controls at sites with predominantly cortical bone (radial and femoral diaphysis), which are known to be more sensitive to calcium intake.     

Differentiation of nonmetastatic and metastatic rodent prostate tumors with high spectral and spatial resolution MRI.

MR images can be acquired with high spectral and spatial resolution to precisely measure lineshapes of the water and fat resonances in each image voxel. Previous work suggests that the high-resolution spectral information can be used to improve image contrast, SNR, sensitivity to contrast agents and to physiologic and biochemical processes that affect local magnetic susceptibility gradients. The potential advantages of high-resolution spectroscopic imaging (SI) suggest that it might be useful for early detection and characterization of tumors. The present experiments evaluate the use of high-resolution SI to discriminate between metastatic and nonmetastatic rodent Dunning prostate tumors. SI datasets were obtained at 4.7 Tesla with an in-plane resolution of 350-500 micron in a single 1.0-mm slice, and 6-8 Hz spectral resolution, before and after i.v. injection of an iron oxide contrast agent. Images of water signal peak height in nonmetastatic tumors were smoother in the tumor interior than images of metastatic tumors (P <.004 by t-test) before contrast media injection. This difference was stronger in contrast-enhanced images (P <.0004). In addition, the boundary between the tumor and muscle was more clearly demarcated in nonmetastatic than metastatic tumors. Combinations of image texture, tumor edge morphology, and changes in T2* following contrast media injection improved discrimination between metastatic and nonmetastatic tumors. The data presented here do not demonstrate that effective discrimination between metastatic and nonmetastatic tumors depends on the use of high-resolution SI. However, the results suggest that SI and/or other MR methods that provide similar contrast might be used clinically for early and accurate detection of metastatic disease.