The Response of the Ductus Arteriosus to Prostaglandins

1973 ◽  
Vol 51 (3) ◽  
pp. 220-225 ◽  
Author(s):  
F. Coceani ◽  
P. M. Olley
Keyword(s):  
Ductus Arteriosus ◽  
Dose Range ◽  
Similar Degree ◽  
Fetal Life ◽  
Aerobic Conditions ◽  
Additional Finding ◽  
Before And After ◽  
Prostaglandins E

Effects of various prostaglandin types on strips of lamb ductus arteriosus were investigated under anaerobic and aerobic conditions. Prostaglandins E1 and E2 relaxed markedly the anoxic ductus over a dose range from 10−9 to 10−5 M whereas they had little or no effect on the tissue after exposure to oxygen. This is in contrast to papaverine which relaxed the ductus to a similar degree before and after exposure to oxygen. An additional finding was that prostaglandins E1 and E2 are less active on the anoxic tissue depolarized by excess potassium. The greater effectiveness of prostaglandins on the anoxic ductus suggests a role for these compounds in the regulation of the vessel tone during fetal life.

Combined noninvasive assessment of the patent ductus arteriosus in the preterm infant before and after indomethacin treatment

1984 ◽  
Vol 54 (10) ◽  
pp. 1300-1304 ◽  
Author(s):  
Jeffrey F. Smallhorn ◽  
Robert Gow ◽  
Peter M. Olley ◽  
Robert M. Freedom ◽  
Paul R. Swyer ◽  
...  
Keyword(s):  
Patent Ductus Arteriosus ◽  
Preterm Infant ◽  
Ductus Arteriosus ◽  
Before And After ◽  
Noninvasive Assessment ◽  
Patent Ductus ◽  
Indomethacin Treatment

TCAD Modeling of Nanoscale Bulk FinFET Structures with Account of Radiation Exposure

2021 ◽  
Vol 26 (5) ◽  
pp. 374-386
Author(s):  
K.O. Petrosyants ◽  
◽  
D.S. Silkin ◽  
D.A. Popov ◽  
Bo Li ◽  
...  
Keyword(s):  
Dose Range ◽  
Channel Length ◽  
Bulk Silicon ◽  
Test Set ◽  
Topological Parameters ◽  
Basic Model ◽  
Effective Mobility ◽  
Before And After ◽  
Semi Empirical ◽  
Radiation Type

Transition from planar MOSFET structures to FinFET 3D structures ensures various radiation type resistance. However, the characteristics of radiation-exposed devices made at different factories vary considerably and it is hard to explain FinFET structures’ radiation resistance dependence on variations of their physical and topological parameters and electrical modes. In this work, a RAD-TCAD model of FinFET on bulk silicon was developed. Additional semi-empirical radiation dependences specific to FinFET structures were introduced into the basic model of a nanometer MOSFET: the charge carrier effective mobility, the traps concentration in the SiO2 and HfO2 oxides and at the Si / SiO2 interface. The model was implemented in the Sen-taurus Synopsys TCAD environment. The model was validated on a test set of FinFET structures with a channel length from 60 nm to 7 nm before and after exposure to gamma irradiation in the dose range up to 1 Mrad. Comparison of the modeled and experimental I-V characteristics has shown an error of no more than 15 %.

Comparison of Cerebral Blood Flow after Venesection of Bronchitic Secondary Polycythaemic and Primary Polycythaemic Patients

1983 ◽  
Vol 28 (4) ◽  
pp. 332-337 ◽  
Author(s):  
P. d'A. Semple ◽  
G. D. O. Lowe ◽  
J. Patterson ◽  
G. H. Beastall ◽  
J. O. Rowan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Similar Degree ◽  
Chronic Obstructive ◽  
Blood Oxygen ◽  
Before And After ◽  
Obstructive Airways Disease ◽  
Flow Improvement ◽  
Chronic Obstructive Airways Disease ◽  
Symptomatic Benefit

Cerebral blood flow was measured before and after lowering of haematocrit in four patients with primary polycythaemia and in nine with polycythaemia secondary to chronic obstructive airways disease. Cerebral blood flow values in each group were abnormally low to a similar degree at the start of the study and the degree of rise in cerebral blood flow per unit fall in haematocrit after venesection also was similar in each. Oxygen delivery fell despite increased cerebral blood flow and symptomatic benefit was infrequent. In male secondary polycythaemic patients rise in cerebral blood flow was not associated with any improvement in hypothalamo-pituitary-testicular function which we had previously noted to be suppressed in such hypoxic subjects. Our findings suggest viscosity changes rather than alteration in blood oxygen carriage to be responsible for cerebral blood flow improvement. It is concluded that therapeutic venesection in such patients should be applied with caution.

In Reply: Cerebral Blood Flow

PEDIATRICS ◽  
1982 ◽  
Vol 70 (6) ◽  
pp. 1013-1014
Author(s):  
RAUL BEJAR
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Gastrointestinal Tract ◽  
Ductus Arteriosus ◽  
Left Ventricular ◽  
Blood Flows ◽  
Before And After ◽  
Regional Blood Flows ◽  
Left Ventricular Output ◽  
Patent Ductus

Baylen and Emmanouilides give the impression that their abstract was misquoted in our commentary. We would like to explain our interpretation of their data. In the abstract, Baylen et al indicate that they measured regional blood flows (RBF) in premature fetal lambs, expressing them as a percentage of the left ventricular output (LVO) before and after patent ductus arteriosus (PDA) closure. Their results (percent of LVO) before and after PDA closure were: lung, 42.7% vs 8.4% (P < .01); carcass, 35% vs 55% (P < .01); heart, 5.5% vs 10.2% (P < .05); gastrointestinal tract, 5.1% vs 9.3% (P < .05); brain, 2.7% vs 3.4% (P = NS); kidney, 2.2% vs 3.3% (P = NS); liver, 3.2% vs 5.7% (P = NS).

scholarly journals NT-proBNP level and left ventricle diameters before and after transcatheter closure of PDA and VSD

2018 ◽  
Vol 58 (5) ◽  
pp. 213-20
Author(s):  
Devy Kusmira ◽  
Ria Nova ◽  
Achirul Bakri
Keyword(s):  
Left Ventricle ◽  
Transcatheter Closure ◽  
Ductus Arteriosus ◽  
Left Ventricular ◽  
Internal Diameter ◽  
Positive Correlation ◽  
Amino Terminal ◽  
Muscle Stretching ◽  
Before And After ◽  
Moderate Positive Correlation

Background Amino-terminal pro-B-type natriuretic peptide (NT-proBNP) levels before and after transcatheter closure may correlate with changes in left ventricular internal diameter end diastole (LVIDd) and end systole (LVIDs). Patent ductus arteriosus (PDA) and ventricular septal defect (VSD) are structural abnormalities which effects cardiac hypertrophy. Cardiac muscle stretching decreases after closure, followed by reduced left ventricle diameters and decreased NT-proBNP levels. Objective To analyze for possible correlations between NT-proBNP levels and left ventricle diameters before and after transcatheter closure. Methods Subjects were PDA and VSD patients who underwent transcatheter closure in the Pediatrics Department of dr. Moh Hoesin Hospital, Palembang, South Sumatera, from May 2016 to March 2017. Measurement of NT-proBNP levels and echocardiography were performed before closure, as well as one and three months after closure. Results There were 34 subjects (15 girls) with median age of 91.5 months. Median NT-proBNP levels were significantly reduced after closure: before closure 111.7pg/mL, one month after closure 62pg/mL, and three months after closure 39 pg/mL (P<0.05). Median LVIDd and LVIDs were also significantly reduced after closure [LVIDd: 39.5mm before, 34.5mm one mo after, and 32.5mm 3 mo after (P<0.05); LVIDs: 23.9mm before, 20.5mm 1 mo after, and 20.0mm 3 mo after (P<0.05)]. At one month after closure, there was a moderate positive correlation between NT-proBNP levels and LVIDd (r=0.432; P=0.011), but no correlation with LVIDs (r=0.287; P=0.100). At three months after closure, there was a significant moderate positive correlation between changes of NT-proBNP levels and changes of LVIDd (r=0.459; P=0.006), as well as LVIDs (r=0.563; P=0.001). Conclusion In pediatric PDA and VSD patients, NT-proBNP levels have a significant positive correlation with diastolic and systolic left ventricle diameters at three months after closure. Decreased NT-proBNP levels may be considered as a marker of closure effectiveness.

Which Inotropic Drug, Dobutamine or Milrinone, Is Clinically More Effective in the Treatment of Postligation Cardiac Syndrome in Preterm Infants?

2020 ◽  
Author(s):  
Levent Korkmaz ◽  
Ahmet Ozdemir ◽  
Özge Pamukçu ◽  
Tamer Güneş ◽  
Mehmet Adnan Ozturk
Keyword(s):  
Blood Pressure ◽  
Operating Characteristic ◽  
Ductus Arteriosus ◽  
Area Under The Curve ◽  
Therapeutic Effects ◽  
Study Group ◽  
Cardiac Syndrome ◽  
Before And After ◽  
The Difference

Objective This study aimed to detect which of the two main medicines suggested in the treatment of postligation cardiac syndrome (PLCS)—dobutamine or mirinone—possesses a more therapeutic effect. While doing this, clinicians are provided with a broader perspective on the treatment and follow-up of cases. The desire was to increase the treatability and monitor ability of the cases in question and hence their survivability. Study Design A retrospective review of a cohort of infants with PLCS was conducted between March 2012 and December 2018. In the treatment of infants with PLCS, dobutamine (dobutamine study group-DSG) or milrinone (milrinone study group-MSG) was used. The respiration, cardiac, echocardiography, and perfusion parameters of the cases were assessed both before and after ligation. Based on the data obtained, both the effects of the medicines on PLCS and the difference between their therapeutic effects were studied. The accuracy of prognostication was assessed with receiver operating characteristic analyses. Results PLCS was detected in 29 (34.1%) of 85 patent ductus arteriosus ligation cases in total. Of all the PLCS cases, 13 (44.8%) were treated with dobutamine and 16 (55.2%) with milrinone. It was observed that the effects of the medicines on the respiratory system and cardiovascular system manifested in the third and 6th hour, respectively. It was detected that both medicines had more effect on the systolic blood pressure (SBP) (area under the curve [AUC]: 0.997/0.996, p = 0.001/0.002) than on the diastolic blood pressure (AUC: 0.911/0.843, p = 0.032/0.046). Conclusion Dobutamine and milrinone, two primary medicines that can be used in the treatment of cases with PLCS, possess similar therapeutic effects on this pathology. In addition, their postoperative therapeutic effects on the SBP are more in the foreground.

Action of prostaglandins, endoperoxides, and thromboxanes on the lamb ductus arteriosus

1978 ◽  
Vol 234 (2) ◽  
pp. H117-H122 ◽  
Author(s):  
F. Coceani ◽  
I. Bishai ◽  
E. White ◽  
E. Bodach ◽  
P. M. Olley
Keyword(s):  
Ductus Arteriosus ◽  
Thromboxane A2 ◽  
Fetal Life ◽  
Synthetic Reaction ◽  
Pg E2 ◽  
Dose Dependent

Prostaglandin (PG) E2, the PG endoperoxides PGG2 and PGH2, and enzymatically generated PGI2 and thromboxane A2 (TXA2) were tested in vitro on circular strips of ductus arteriosus from mature fetal lambs. Both PGE2 and the PG endoperoxides produced a dose-dependent relaxation of the ductus at low PO2 (7-11 torr), and their action was reduced or abolished at high PO2 (410-660 torr). PGE2, however, was more potent than the endoperoxides. The reaction mixture containing PGI2 relaxed the hypoxic ductus, but this response was not due to PGI2 but to two, more stable and as yet unidentified, compounds, one of which is most certainly PGE2. TXA2 was inactive on the vessel at low and high PO2. These results confirm that PGE2 is the most effective PG acting on the ductus and provide further support to the hypothesis that this PG is responsible for patency of the vessel during fetal life. PGE2 action, however, may be complemented by that of another endoperoxide derivative formed in the PGI2 synthetic reaction which remains to be identified.

Intrauterine hypertension decreases lung VEGF expression and VEGF inhibition causes pulmonary hypertension in the ovine fetus

2003 ◽  
Vol 284 (3) ◽  
pp. L508-L517 ◽  
Author(s):  
Theresa R. Grover ◽  
Thomas A. Parker ◽  
Jeanne P. Zenge ◽  
Neil E. Markham ◽  
John P. Kinsella ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Protein Content ◽  
Ductus Arteriosus ◽  
Late Gestation ◽  
Receptor Protein ◽  
Vegf Receptor ◽  
Fetal Life ◽  
Vegf Expression ◽  
Vegf Signaling ◽  
Vegf Inhibition

Although vascular endothelial growth factor (VEGF) plays a vital role in lung vascular growth in the embryo, its role in maintaining endothelial function and modulating vascular structure during late fetal life has not been studied. We hypothesized that impaired lung VEGF signaling causes pulmonary hypertension, endothelial dysfunction, and structural remodeling before birth. To determine whether lung VEGF expression is decreased in an experimental model of persistent pulmonary hypertension of the newborn (PPHN), we measured lung VEGF and VEGF receptor protein content from fetal lambs 7–10 days after ductus arteriosus ligation (132–140 days gestation; term = 147 days). In contrast with the surge in lung VEGF expression during late gestation in controls, chronic intrauterine pulmonary hypertension reduced lung VEGF expression by 78%. To determine whether VEGF inhibition during late gestation causes pulmonary hypertension, we treated fetal lambs with EYE001, an aptamer that specifically inhibits VEGF165. Compared with vehicle controls, EYE001 treatment elevated pulmonary artery pressure and pulmonary vascular resistance by 22 and 50%, respectively, caused right ventricular hypertrophy, and increased wall thickness of small pulmonary arteries. EYE001 treatment reduced lung endothelial nitric oxide synthase protein content by 50% and preferentially impaired the pulmonary vasodilator response to ACh, an endothelium-dependent agent. We conclude that chronic intrauterine pulmonary hypertension markedly decreases lung VEGF expression and that selective inhibition of VEGF165 mimics the structural and physiological changes of experimental PPHN. We speculate that hypertension downregulates VEGF expression in the developing lung and that impaired VEGF signaling may contribute to the pathogenesis of PPHN.

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