RNA sequencing confirms similarities between PPI-responsive oesophageal eosinophilia and eosinophilic oesophagitis.

BACKGROUND: Although current American guidelines distinguish proton pump inhibitor-responsive oesophageal eosinophilia (PPI-REE) from eosinophilic oesophagitis (EoE), these entities are broadly similar. While two microarray studies showed that they have similar transcriptomes, more extensive RNA sequencing studies have not been done previously. AIM: To determine whether RNA sequencing identifies genetic markers distinguishing PPI-REE from EoE. METHODS: We retrospectively examined 13 PPI-REE and 14 EoE biopsies, matched for tissue eosinophil content, and 14 normal controls. Patients and controls were not PPI-treated at the time of biopsy. We did RNA sequencing on formalin-fixed, paraffin-embedded tissue, with differential expression confirmation by quantitative polymerase chain reaction (PCR). We validated the use of formalin-fixed, paraffin-embedded vs RNAlater-preserved tissue, and compared our formalin-fixed, paraffin-embedded EoE results to a prior EoE study. RESULTS: By RNA sequencing, no genes were differentially expressed between the EoE and PPI-REE groups at the false discovery rate (FDR) ≤0.01 level. Compared to normal controls, 1996 genes were differentially expressed in the PPI-REE group and 1306 genes in the EoE group. By less stringent criteria, only MAPK8IP2 was differentially expressed between PPI-REE and EoE (FDR = 0.029, 2.2-fold less in EoE than in PPI-REE), with similar results by PCR. KCNJ2, which was differentially expressed in a prior study, was similar in the EoE and PPI-REE groups by both RNA sequencing and real-time PCR. CONCLUSION: Eosinophilic oesophagitis and PPI-REE have comparable transcriptomes, confirming that they are part of the same disease continuum.

Lumped parameter estimation for the embryonic chick vascular system: a time-domain approach using MLAB.

We have evaluated several lumped parameter analog models for the early chick embryonic vascular system that may be used to infer loading characteristics of the developing heart. We measured dorsal aortic pressure and flow simultaneously with a servo-null pressure system and a pulsed Doppler velocimeter. Four different analog circuit models were chosen for comparisons. We formulated the time-domain differential equations specifying the relations between pressure and flow in the models, and then estimated the lumped parameters that produced the best fit. The MLAB mathematical modeling software was used for solving differential equations, and for minimizing the difference between model-predicted values and experimental data. The traditional three-element Windkessel model with an added inductance term was most often the best-fitting model. This is compatible with the previous study using a frequency-domain approach. The procedures developed for the current study are adaptable for the study of a variety of nonlinear models, and distributed parameter models for mammalian cardiovascular development with mechanically, pharmacologically, or genetically altered conditions.

Characterization of embryonic aortic impedance with lumped parameter models.

We systematically constructed and analyzed 18 analog circuit models to characterize embryonic arterial impedance. We measured simultaneous dorsal aortic pressure and flow, and we calculated experimental impedance in stage 24 chick embryos (n = 15). Cycle length was altered with thermal probes to improve frequency resolution of the impedance spectrum. Models were categorized according to the framework and the location of inductance and resistance terms. Models were excluded if they failed to reproduce the fundamental characteristics of the experimental impedance spectrum. We used weighted least-square parameter optimization to fit the model impedance curves to the experimental impedance data. Models that failed to converge parameters or revealed overparameterization were also excluded. We assessed goodness of fit in the frequency domain with the F-test, Akaike information criterion, and Schwarz criterion to determine the best-fit model. The addition of a serial inductance term to the traditional three-element windkessel model improved fit by reproducing modulus fluctuation and phase zero crossing (P < 0.001). Thus, despite dramatic differences in scale and geometry, the embryonic and mature vascular systems can be described using lumped parameter circuit models.

Linearity of pulsatile pressure-flow relations in the embryonic chick vascular system.

The calculation and modeling of vascular input impedance are based on the assumption that pressure and flow are linearly related in the frequency domain. However, this assumption has not been proven for the embryonic circulation. Therefore, we investigated the linearity of pulsatile pressure flow relations in vivo with acute alterations in cycle length. We simultaneously measured dorsal aortic pressure with a servonull system and flow velocity with a 20-MHz pulsed-Doppler system in stage 24 chick embryos (n = 38). Cycle length was acutely altered using thermal probe(s) applied to the sinus venosus. We determined the impedance spectra at several cycle lengths for each embryo and a reference curve from a three-element Windkessel model with the use of nonlinear curve fitting. We then assessed the scatter of experimental impedance along the reference curve as a measure of linearity in the frequency domain. We found that mean vascular resistance did not change after thermal probe applications (P > .20 for each), indicating that acute alterations in cycle length did not alter peripheral vascular properties. Superpositioned impedance spectra showed minimal scatter along the model impedance from 0 to 6 Hz. Goodness of fit values (R2) were near unity (.94 to .97) and were similar for all interventions (P > .07 for Fisher's z, by F test). Above 6 Hz, both modulus and phase spectra exhibited significant scatter (P < .05, by F test). Experimental impedance spectra tended to have a fluctuation and a phase-zero crossover, indicating significant wave reflection in the embryonic circulation. Thus, the embryonic vascular system can be approximated as a linear system from 0 to 6 Hz, the range in which the majority (96.0 +/- 0.18%) of hydraulic energy is dissipated.

Coronary artery-pulmonary artery fistula in pulmonary atresia with ventricular septal defect.

This paper reports two patients presenting a combination of coronary artery-pulmonary artery fistula and pulmonary atresia with ventricular septal defect. A confluent central pulmonary artery arose from the proximal portion of the left coronary artery in both patients. The fistulous segment between the coronary artery and the central pulmonary artery was large, and no coronary arterial stenosis was found in either patient. Besides this fistulous origin of the pulmonary blood supply, large collateral vessels originated from the descending aorta in both patients. Neither patient has shown findings of myocardial ischemia, at least in consecutive rest and exercise electrocardiograms. Both patients were successfully operated, at the ages of 3 and 8 years, respectively. The clinical and embryological implications of this rare malformation are briefly reviewed.

Maximal hemodynamic response after the Fontan procedure: Doppler evaluation during the treadmill test.

After undergoing the Fontan procedure for congenital heart disease, 16 young patients performed a maximal treadmill test according to the Bruce protocol. The peak velocity of the blood flow in the ascending aorta, stroke index, and cardiac index were measured by continuous-wave Doppler echocardiography at rest and at each stage of the test. The results were compared with those from 18 normal children. The body surface area was similar in the two groups. The endurance time was 37% shorter in the Fontan group than in the control group. From the beginning of exercise until the sixth minute, the increase in stroke index was lower in the Fontan group (NS). After that point, the stroke index was maintained at a high level in the control group but decreased toward its original level in the Fontan group. The response of cardiac index to exercise in the two groups was comparable until the sixth minute, after which the Fontan group failed to maintain an ascending curve. All the hemodynamic values were significantly higher in the control group at maximal exercise; at this point the cardiac index had increased 79% in the Fontan group and 170% in the control group. The subnormal response of the stroke volume at submaximal exercise and the subsequent decrease at maximal exercise following the Fontan procedure are important hemodynamic findings.

Developmental changes in flow-wave propagation velocity in embryonic chick vascular system.

We analyzed flow-wave propagation velocity in the early embryonic vascular system and its responses to acute alterations in circulating blood volume. Two 20-MHz pulsed Doppler velocimeters were positioned along the arterial system in stage 18 (n = 12), 21 (n = 10), and 24 (n = 11) chick embryos. Distance between the two measurement sites was measured by video-microscopy. Phase velocity was calculated using Fourier transform up to the fourth harmonics. Wave-front velocity was also calculated by threshold technique. In a subset of embryos at stage 24 (n = 10), circulating blood volume was acutely altered to change stroke volume. Mean phase velocity increased from 42.9 +/- 3.3 to 95.8 +/- 7.5 cm/s from stage 18 to 24 (P < 0.05 by analysis of variance), whereas wave-front velocity increased from 52.8 +/- 2.4 to 72.2 +/- 5.2 cm/s. Stroke volume and mean aortic pressure paralleled the changes in mean phase velocity and wave-front velocity in normal development and in response to changes in circulating blood volume. Thus developmental changes in wave-propagation velocity were consistent with changes in the size of the vascular system, pressure range, and elastic properties of the arterial wall during systemic vasculogenesis in the embryo.

Dorsal aortic impedance in stage 24 chick embryo following acute changes in circulating blood volume.

The effects of acute changes in circulating blood volume on embryonic vascular hemodynamics were evaluated with the use of input impedance. We simultaneously measured dorsal aortic pressure with a servo-null system and flow velocity with a 20-MHz pulsed Doppler system in n = 90 stage 24 chick embryos. We withdrew or infused 1,3, or 5 microliters of blood via a second-order vitelline vein (n = 10 per group). In addition, we withdrew and then infused or infused and then withdrew 3 microliters (n = 5 per group). Characteristic impedance, peripheral resistance, arterial compliance and elastance, and hydraulic power as well as basic hemodynamic parameters were evaluated on the basis of the three-element windkessel model. In response to withdrawal, mean and pulse pressure, mean flow, arterial compliance, and hydraulic power decreased, whereas peripheral resistance and arterial elastance increased in a dose-dependent manner. Results in response to infusion were converse in effect. Characteristic impedance was unchanged by volume alternations. Oscillatory fraction of hydraulic power was higher than mature circulation and remained relatively constant during interventions, which indicates well-regulated energy efficiency for vascular growth in the embryonic circulation. A hysteresis relevant to altered peripheral resistance was present after multiple interventions. Embryonic vasculature is sensitive to circulating blood volume and preserve blood pressure at the expense of blood flow. In the absence of autonomic innervation, embryonic vascular tone may be regulated by mechanical properties of the vessel (the law of Laplace) and/or vasoactive substances.

Ventricular-vascular uncoupling by acute conotruncal occlusion in the stage 21 chick embryo.

Embryonic ventricular diastolic and systolic function was evaluated during normal ejection (coupled) and during acute ventricular outflow tract occlusion (uncoupled) in the stage 21 chick embryo. We simultaneously measured ventricular pressure with a servo-null system and ventricular dimensions using video microscopy. Experimental protocols included 1) baseline recording followed by acute conotruncal (CT) ligation (n = 15) and 2) baseline recording, preload increase using Krebs-Henseleit buffer (3 microliters), preload reduction via venous hemorrhage, and then CT occlusion (n = 20). Ventricular epicardial cross-sectional area was converted to internal volume using wall volume measures and assuming an ellipsoid geometry to produce pressure-volume loops. We calculated the time constant of ventricular pressure decline using a monoexponential decay function with a pressure asymptote. As previously noted, heart rate was unaffected by acutely altered preload or afterload. CT ligation increased end-systolic pressure, maximal +dP/dt, and the time constant of ventricular pressure decline and decreased stroke volume indexed for end-diastolic volume. Thus the embryonic ventricle has significant contractile reserve masked in vivo by the dynamic coupling between the ventricle and arterial circulation.

Acute nonlymphocytic leukemia with basophilic differentiation and t(9,11)(p22,q23) in a child.

A 20-month-old child was treated for acute nonlymphocytic leukemia (ANLL) with basophilic differentiation. His leukemic cells also had the cytogenetic abnormality of t(9,11)(p22,q23). Although immature blasts responded well to induction therapy with etoposide, the leukemic cells that were more differentiated toward basophils were quite refractory to the drug. However, complete remission was finally achieved with a conventional multidrug regimen.

Succinimide derivatives. II. Synthesis and antipsychotic activity of N-[4-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]butyl]-1,2-cis- cyclohexanedicarboximide (SM-9018) and related compounds.

Cyclic imides bearing omega-(4-benzisothiazol-3-yl-1-piperazinyl)alkyl moieties were synthesized and tested for antipsychotic activity. The in vitro binding affinities of these compounds were examined for dopamine 2 (D2) and serotonin 2 (5-HT2) receptor sites. Structure-activity relationships within these series are discussed. One of these compounds, N-[4-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]butyl]-1,2-cis- cyclohexamedicarboximide (SM-9018), was found to be more potent and more selective in vivo than tiospirone in its antipsychotic activity. SM-9018 (17) is currently undergoing clinical evaluation as a selective antipsychotic agent.

In vivo assessment of embryonic cardiovascular dimensions and function in day-10.5 to -14.5 mouse embryos.

Embryonic cardiovascular function has been extensively studied in vivo in the chick embryo. However, the geometry of mammalian and avian hearts differs; the mammalian cardiovascular system is coupled to both yolk sac and placental circulations, and unique murine genetic models associated with structural and functional cardiovascular defects are now available. We therefore adapted techniques validated for the chick embryo to define cardiovascular dimensions and function in the mouse embryo. We bred C3HeB female and C57B1/J6 male mice and ICR pairs for experiments on embryonic days (EDs) 10.5 to 14.5 (n = 130 dams). After maternal anesthesia (pentobarbital, 60 mg/kg IP), laparotomy, and sequential regional hysterotomy, we exposed and then imaged individual embryos at 60 Hz (video) in the ventral and/or left anterior oblique views while maintaining uteroplacental continuity. We measured epicardial chamber dimensions and then calculated right and left ventricular elliptical volumes from ares. In addition, we measured pulsed-Doppler blood velocity across the atrioventricular cushions and ventricular outflow tract. We maintained embryonic temperature with a heated surgical platform, topical oxygenated and warmed buffer, and warming lamps. Embryonic heart rate increased from 124.7 +/- 5.2 to 194.3 +/- 13.2 bpm from EDs 10.5 to 14.5 (P < .01). Right and left ventricular end-diastolic and end-systolic dimensions increased (P < .05 by ANOVA for each). Maximal ventricular mean inflow and outflow velocities increased from 62.33 +/- 4.06 to 106.23 +/- 11.59 and from 55.79 +/- 6.11 to 91.61 +/- 6.93 mm/s, respectively (P < .05 by ANOVA for each). Thus, as has been done for chick and rat embryos, the maturation of murine embryonic cardiovascular function can be quantified in vivo, setting the stage for the investigation of structure-function relations in mouse models of cardiovascular development and disease.