Mechanical function of the main pulmonary artery

1962 ◽  
Vol 17 (2) ◽  
pp. 205-208 ◽  
Author(s):  
Dali J. Patel ◽  
Flavio M. De Freitas ◽  
Alexander J. Mallos
Keyword(s):  
Pulmonary Artery ◽  
Vessel Wall ◽  
Water Pressure ◽  
Main Pulmonary Artery ◽  
Mean Value ◽  
Longitudinal Motion ◽  
Wall Velocity ◽  
The Mean ◽  
The Relationship ◽  
Intravascular Pressure

The relationship among the longitudinal strain, circumferential strain, lateral intravascular pressure, blood flow, and longitudinal motion was examined in the main pulmonary artery of living, open-chested dogs. Results indicate: 1) The mean value for longitudinal extensibility was 0.73% change in length per centimeter of water pressure (± .19 sd ± .04 sem). 2) The mean value for volume distensibility was 2.28% change in volume per centimeter of water pressure (± .9 sd ± .17 sem). 3) The magnitude of the radial vessel wall velocity is small. 4) The magnitude of the longitudinal vessel wall velocity, though small over most of the cardiac cycle, may become significant at the beginning of cardiac systole, especially during isoproterenol administration. Submitted on October 3, 1961

Relation between pressure and diameter in main pulmonary artery of man

1963 ◽  
Vol 18 (3) ◽  
pp. 557-559 ◽  
Author(s):  
Joseph C. Greenfield ◽  
Douglas M. Griggs
Keyword(s):  
Elastic Modulus ◽  
Pulmonary Artery ◽  
Heart Surgery ◽  
Cardiac Cycle ◽  
Main Pulmonary Artery ◽  
Open Heart Surgery ◽  
Mean Value ◽  
Cross Sectional ◽  
The Mean ◽  
Intravascular Pressure

The pressure-diameter relationship in the main pulmonary artery of man was estimated in 11 patients undergoing open-heart surgery. The diameter was measured with a recording caliper sutured to the vessel wall. The lateral intravascular pressure was measured with a 20-gauge needle connected directly to a Statham P23Db strain gauge. In the eight patients with normal pulmonary artery pressure the results indicate: 1) the shapes of the pressure and diameter curves are similar; 2) the mean value for the ratio of change in radius to change in pressure (ΔR/ΔP) x 103 was 8.77 cm/cm H2O (±sd 2.10); 3) the mean value for the pressure-strain elastic modulus (Ep) was 159.0 g/cm2 (±sd 26.0); and 4) the mean change in cross-sectional area during an average cardiac cycle was 22.9% of the diastolic value. In three patients with pulmonary hypertension the value of both ΔR/ΔP and the pressure-strain elastic modulus was lower. Submitted on April 27, 1962

Aortic mechanics in the living dog

1961 ◽  
Vol 16 (2) ◽  
pp. 293-299 ◽  
Author(s):  
Dali J. Patel ◽  
Alexander J. Mallos ◽  
Donald L. Fry
Keyword(s):  
Thoracic Aorta ◽  
Abdominal Aorta ◽  
Circumferential Strain ◽  
Absolute Magnitude ◽  
Mean Value ◽  
Blood Velocity ◽  
Longitudinal Motion ◽  
The Mean ◽  
The Relationship ◽  
Intravascular Pressure

The relationship between longitudinal strain, circumferential strain, lateral intravascular pressure, blood velocity, and longitudinal motion was examined in the aortas of 25 living thoracotomized dogs. Electrical calipers with adequate recording characteristics were used for instantaneous measurement of diameter and length. The results indicate: a) with inspiration, the thoracic aorta increased in length and the abdominal aorta shortened. b) During cardiac systole the length in the thoracic aorta increased with a rise in pressure, mean value for longitudinal extensibility x 103 was 15% (α 4.8 S.D., α 1.1 S.E.M.) per centimeter H2O pulse pressure. The mean value for the ratio of circumferential extensibility to longitudinal extensibility was 10. c) The abdominal aorta shortened with cardiac systole. This shortening is thought to be produced by elongating strain of the thoracic aorta. d) The absolute magnitude of aortic wall velocities, both radial and longitudinal, was very small as compared to the blood velocity at the same site. Submitted on August 18, 1960

Mechanical properties and dimensions of the major pulmonary arteries

1960 ◽  
Vol 15 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Dali J. Patel ◽  
Donald P. Schilder ◽  
Alexander J. Mallos
Keyword(s):  
Pulmonary Artery ◽  
Pulse Pressure ◽  
Technical Assistance ◽  
Main Pulmonary Artery ◽  
Pulmonary Arteries ◽  
Cross Sectional ◽  
Measurement Control ◽  
The Mean ◽  
The Right ◽  
The Relationship

The relationship between instantaneous distending pressure and diameter of the pulmonary artery was studied in 18 living thoracotomized dogs. An electrical caliper with adequate recording characteristics was developed for instantaneous diameter measurement. Control observations were made over a range of pressures induced by rapid, right heart dextran-infusion and were compared with those obtained during norepinephrine administration. Results indicate: a) the pulse contours of the pulmonary artery pressure and diameter are essentially identical, indicating negligible inertance and viscous resistance of the vessel wall, b) the mean change in average radius during a cardiac cycle was ±7.8% ± 2.86 S.D. ± .32 S.E.M. (0.48%/cm H2O pulse pressure) under control conditions, c) the ratio of change in radius to pulse pressure, R/P, showed a significant decrease during norepinephrine administration when compared to control values within the same pressure range (P < .01) and d) the cross-sectional area of the main pulmonary artery exceeded that of the right and left combined. Note: (With the Technical Assistance of Alfred G. T. Casper) Submitted on August 25, 1959

scholarly journals AB0101 THE IMPACT OF TIME SPAN TO ACHIEVE BOOLEAN REMISSION FOR MAINTAINING DISEASE ACTIVITY AFTER ACQUISITION IN RHEUMATOID ARTHRITIS PATIENT

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii
Keyword(s):  
Rheumatoid Arthritis ◽  
Disease Activity ◽  
Disease Duration ◽  
Remission Rate ◽  
Mean Value ◽  
Time Span ◽  
Mean Values ◽  
The Mean ◽  
The Relationship

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared

scholarly journals Localization of DNA in the fibrillar components of the nucleolus: a cytochemical and morphometric study.

1993 ◽  
Vol 41 (6) ◽  
pp. 829-836 ◽  
Author(s):  
M Derenzini ◽  
F Farabegoli ◽  
D Trerè
Keyword(s):  
Morphometric Analysis ◽  
Mean Value ◽  
Morphometric Study ◽  
Dense Fibrillar Component ◽  
Thin Sections ◽  
Fibrillar Center ◽  
The Mean ◽  
Fibrillar Component ◽  
Resting Lymphocytes ◽  
The Relationship

We studied the distribution of DNA in human circulating lymphocyte nucleoli using three different cytochemical methods for selective visualization of DNA in thin sections: the Feulgen-like osmium-ammine reaction, the NAMA-Ur procedure, and the osmium-ammine staining in glycine buffer, pH 1.5. All three methods indicated the presence of uniformly distributed, highly decondensed DNA filaments forming a large solitary agglomerate in the central part of the nucleolar area, corresponding to the solitary large fibrillar center (FC) as revealed by uranium and lead staining. We also studied the relationship between DNA agglomerates and nucleolar fibrillar components in resting and phytohemagglutinin (PHA)-stimulated lymphocytes by morphometric analysis of the areas occupied by these structures. In resting lymphocytes the mean area of the DNA agglomerates was 0.479 micron 2 +/- 0.161 SD, whereas that of FCs was 0.380 micron 2 +/- 0.149 SD, with a ratio of 1.26. In PHA-stimulated lymphocytes the mean area of the DNA agglomerates was 0.116 micron 2 +/- 0.056 SD, whereas that of the FCs was 0.075 micron 2 +/- 0.032 SD, with a ratio of 1.55. In PHA-stimulated lymphocytes we also measured the area occupied by the FCs plus the closely associated dense fibrillar component (DFC). The mean value of these two fibrillar components was 0.206 micron 2 +/- 0.081 SD. These data demonstrate that decondensed DNA filaments are uniformly distributed in the FCs and that in transcriptionally active nucleoli they are also present in the proximal portion of the DFC surrounding the FCs.

Stable Isotopes Analysis of Precipitation in Subtropical Plateau of Yunnan

2014 ◽  
Vol 1010-1012 ◽  
pp. 1059-1063
Author(s):  
Wei Guan ◽  
Tao Fan ◽  
Xiu Qin Zhu
Keyword(s):  
Stable Isotopes ◽  
Rainy Season ◽  
Mean Value ◽  
Dry Season ◽  
Precipitation Line ◽  
Stable Isotopic ◽  
Different Seasons ◽  
Geographical Position ◽  
The Mean ◽  
The Relationship

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.

scholarly journals THE LUCK IN “TALENT VERSUS LUCK” MODELING

2020 ◽  
Vol 23 (03) ◽  
pp. 2050007
Author(s):  
SEAN ELVIDGE
Keyword(s):  
Mean Value ◽  
Maximum Amount ◽  
Random Numbers ◽  
Individual Parameter ◽  
Input Parameters ◽  
The Mean ◽  
Model Variability ◽  
The Impact ◽  
The Relationship

This paper further investigates the Talent versus Luck (TvL) model described by [Pluchino et al. Talent versus luck: The role of randomness in success and failure, Adv. Complex Syst. 21 (2018) 1850014] which models the relationship between ‘talent’ and ‘luck’ on the impact of an individuals career. It is shown that the model is very sensitive to both random sampling and the choice of value for the input parameters. Running the model repeatedly with the same set of input parameters gives a range of output values of over 50% of the mean value. The sensitivity of the inputs of the model is analyzed using a variance-based approach based upon generating Sobol sequences of quasi-random numbers. When using the model to look at the talent associated with an individual who has the maximum capital over a model run it has been shown that the choice for the standard deviation of the talent distribution contributes to 67% of the model variability. When investigating the maximum amount of capital returned by the model the probability of a lucky event at any given epoch has the largest impact on the model, almost three times more than any other individual parameter. Consequently, during the analysis of the model results one must keep in mind the impact that only small changes in the input parameters can have on the model output.

scholarly journals The Relationship Between Degrees of Pre-Operative Anxiety With Pain and Post Operative Answer in Patients Who Undergo C-Section With Spinal Anesthesia

2020 ◽  
Vol 5 (9) ◽  
pp. 389-392
Author(s):  
Boy Olifu Elniko Ginting ◽  
Akhyar Hamonangan Nasution ◽  
Soejat Harto
Keyword(s):  
Spinal Anesthesia ◽  
General Hospital ◽  
Direct Relationship ◽  
Numerical Data ◽  
Total Sample ◽  
Mean Value ◽  
Vas Score ◽  
Unpleasant Feeling ◽  
The Mean ◽  
The Relationship

Anxiety is an unpleasant feeling that is considered a fear of a threatening danger, often the threat is unknown and always includes various emotional and hemodynamic responses experienced by the organism prior to emotional stimulation. To determine the relationship between the degree of pre-operative anxiety with post-operative pain in patients undergoing cesarean sectio with spinal anesthesia techniques at H. Adam Malik Hospital. Descriptive analytic research was conducted at Haji Adam Malik General Hospital in Medan from May to June 2020. The study population was all subjects scheduled to undergo sectio cesarea with spinal anesthesia at Haji Adam Malik General Hospital. The total sample obtained was 28 patients. The normal test of numerical data test was used with the Spearman Correlation test. The research hypothesis was tested using the Mann-Whitney test. In the study conducted on 28 samples divided into 2 groups, it was found that there was a moderate and direct relationship between APAIS scores and VAS scores. Based on this study, it was found that the average preoperative APAIS score was 11.07 (± 3.79). And for the mean value of postoperative VAS is 2.37 (± 1.04). In the result of this study it was found that there was a moderate and unidirectional relationship to the APAIS score and this VAS score (p <0.05). While the preoperative APAIS score was 11.07 (± 3.79). And for the mean postoperative VAS-A value is 3.33 (± 1.03). In the result of this study also found that there is a strong and direct relationship in the APAIS score and this VASA score (p<0.05). There is a moderate and direct relationship between APAIS scores and this VAS score and that there is a strong and direct relationship in the APAIS score and this VAS-A score

scholarly journals DECISION MAKING FOR DEVICE CLOSURE IN ADULTS WITH ‘HYPERTENSIVE PDA’–NON-INVASIVE CRITERIA: IMMEDIATE RESULTS

2021 ◽  
Vol 70 (Suppl-4) ◽  
pp. S762-67
Author(s):  
Ahsan Beg ◽  
Abdul Malik ◽  
Amjad Mahmood ◽  
M Younas ◽  
Fakher -e- Fayaz
Keyword(s):  
Pulmonary Hypertension ◽  
Retrospective Study ◽  
Pulmonary Artery ◽  
Main Pulmonary Artery ◽  
Tertiary Care ◽  
Referral Hospital ◽  
Device Closure ◽  
X Ray ◽  
Non Invasive ◽  
The Mean

Objective: To find the mean pulmonary artery pressures (PAP) in adults (>12 years) Patent Ductus Arteriosus (PDA) with ‘reversible pulmonary hypertension’ after the device closure. Residual PDA and immediate complications (embolization, pulse loss, obstruction in the aorta or pulmonary artery) are to be reported. Study Design: Retrospective study. Place and Duration of Study: Tertiary Care Referral Hospital, from Aug 2007 to Jun 2020. Methodology: This retrospective study is descriptive. Data collected by convenience sampling from 3 tertiary care referral hospital. 981 patients were undergone PDA device closure during the period from Aug 2007 to June 2020. After informed consent, an initial assessment was done by history, clinical examination, x-ray chest PA view, electrocardiography (ECG), and transthoracic echocardiography (TTE). Reversible pulmonary hypertension was labeled based on non-invasive criteria including room air saturation >93% and cardiomegaly on x-ray chest. Patients who had <93% and normal heart size on x-ray chest were excluded. The lower limit for age was 12 years. Results: Nine Hundred Eighty One patients had undergone PDA device closure. 32 (n=32/981 3.3%) had fulfilled our inclusion criteria. The mean age was 22 ± 9 (13–45) years. Mean weight was 41 ± 11 (25-66) kg. Successful device closure was done in 30 patients (93.7%). Mean diameter of PDA was 7 ± 0.1 (4.5-13 mm. Mean PAP decreased from 59 ± 13 mmHg to 38 ± 19 mmHg (p<0.05). Commonest device used was Shasma duct occluder (n=16/32 50%) followed by Occlutech Duct Occluder (n=7/32 21.9%), while 2 had muscular VSD device (n=5/32 15.6%). In 2 patients, there was an underestimation of the size of PDA so the device was retrieved and replaced with another larger one successfully. Two patients had the device fully dropped into the main pulmonary artery before it was released. Larger size device was not available at that time so the patients were referred for surgery. None of our patients had device embolization or residual shunt on echo performed next day to the procedure. Neither any patient had residual pulmonary hypertension on echocardiography. There was no significant obstruction in the aorta in any patients. Two patients had mild left pulmonary artery obstruction. There was no significant obstruction in the aorta in any of our patients. There was pulse loss in 3 patients which were treated successfully with heparin infusion with no residual damage. Conclusion: Device closure is a feasible option in adults with hypertensive PDA while the decision of reversibility is based on non-invasive criteria.

Hypoxia-Induced Changes in the Mechanical Properties of the Mouse Pulmonary Artery

2003 ◽  
Author(s):  
Ryan W. Kobs ◽  
Nidal E. Muvarak ◽  
Naomi C. Chesler
Keyword(s):  
Mechanical Properties ◽  
Pulmonary Hypertension ◽  
Pulmonary Artery ◽  
Vascular Remodeling ◽  
Hypobaric Hypoxia ◽  
Vessel Wall ◽  
Main Pulmonary Artery ◽  
Collagen Content ◽  
Pulmonary Vascular Remodeling ◽  
Induced Changes

Hypobaric hypoxia produces pulmonary hypertension in mice which causes pulmonary vascular remodeling. To study the biomechanics of this process, mice were exposed to hypoxia for 0-(control), 10-, and 15-days. Using a pressurized arteriograph system, mechanical properties of the main pulmonary artery were measured and compared to the biological changes in the vessel wall measured histologically. 10- and 15-day hypoxic vessels were significantly stiffer when compared to 0-day vessels. This stiffness correlated with greater elastin and collagen content in the vessel wall.

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