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Frontiers in Endocrinology 2023Endothelial functions in controlling blood flow in placental circulation are still unclear. The present study compares vascular dilations between placental circulation...
OBJECTIVE
Endothelial functions in controlling blood flow in placental circulation are still unclear. The present study compares vascular dilations between placental circulation and other vessels, as well as between normal and preeclampsia placental vessels.
METHODS
Placental, umbilical, and other vessels (cerebral and mesenteric arteries) were collected from humans, sheep, and rats. Vasodilation was tested by JZ101 and DMT. Q-PCR, Western blot, and Elisa were used for molecular experiments.
RESULTS
Endothelium-dependent/derived vasodilators, including acetylcholine, bradykinin, prostacyclin, and histamine, mediated no or minimal dilation in placental circulation, which was different from that in other vessels in sheep and rats. There were lower mRNA expressions of muscarinic receptors, histamine receptors, bradykinin receptor 2, endothelial nitric oxide synthesis (eNOS), and less nitric oxide (NO) in human umbilical vessels when compared with placental vessels. Exogenous NO donors (sodium nitroprusside, SNP) and soluble guanylate cyclase (sGC) activators (Bay41-2272) decreased the baseline of vessel tone in placental circulation in humans, sheep, and rats, but not in other arteries. The sGC inhibitor ODQ suppressed the reduced baseline caused by the SNP. The decreased baseline by SNP or Bay41-2272 was higher in placental vessels than in umbilical vessels, suggesting that the role of NO/sGC is more important in the placenta. NO concentrations in preeclampsia placental vessels were lower than those in control, while no significant change was found in umbilical plasma between the two groups. eNOS expression was similar between normal and preeclampsia placental vessels, but phosphorylated eNOS levels were significantly lower in preeclampsia. Following serotonin, SNP or Bay41-2272-mediated dilations were weaker in preeclampsia placental vessels. The decreased amplitude of SNP- or Bay41-2272 at baseline was smaller in preeclampsia. The decreased amplitudes of ODQ + SNP were comparable between the two groups. Despite higher beta sGC expression, sGC activity in the preeclampsia placenta was lower.
CONCLUSION
This study demonstrated that receptor-mediated endothelium-dependent dilation in placental circulation was significantly weaker than other vessels in various species. The results, showed firstly, that exogenous NO played a role in regulating the baseline tone of placental circulation sGC. Lower NO production and decreased NO/sGC could be one of the reasons for preeclampsia. The findings contribute to understanding specific features of placental circulation and provide information about preeclampsia in placental vessels.
Topics: Female; Rats; Humans; Pregnancy; Sheep; Animals; Nitric Oxide; Placenta; Placental Circulation; Dilatation; Pre-Eclampsia; Guanylate Cyclase; Histamine
PubMed: 37293496
DOI: 10.3389/fendo.2023.1182636 -
Computers in Biology and Medicine Dec 2021In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in...
In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in silico and ex-vivo approaches. Three-dimensional artery models were reconstructed from OCT images. Stent deployment and post-dilation with various inflation pressures were performed through both the finite element method (FEM) and ex vivo experiments. Results from FEM agreed very well with the ex-vivo measurements, interms of lumen areas, stent underexpansion, and strut malapposition. In addition, computational fluid dynamics (CFD) simulations were performed to delineate the hemodynamic alterations after stent deployment and post-dilations. A pressure time history at the inlet and a lumped parameter model (LPM) at the outlet were adopted to mimic the aortic pressure and the distal arterial tree, respectively. The pressure drop across the lesion, pertaining to the clinical measure of instantaneous wave-free flow ratio (iFR), was investigated. Results have shown that post-dilations are necessary for the lumen gain as well as the hemodynamic restoration towards hemostasis. Malapposed struts induced much higher shear rate, flow disturbances and lower time-averaged wall shear stress (TAWSS) around struts. Post-dilations mitigated the strut malapposition, and thus the shear rate. Moreover, stenting induced larger area of low TAWSS (<0.4 Pa) and lager volume of high shear rate (>2000 s), indicating higher risks of in-stent restenosis (ISR) and stent thrombosis (ST), respectively. Oscillatory shear index (OSI) and relative residence time (RRT) indicated the wall regions more prone to ISR are located near the malapposed stent struts.
Topics: Computer Simulation; Coronary Vessels; Dilatation; Hemodynamics; Humans; Stents; Tomography, Optical Coherence
PubMed: 34715552
DOI: 10.1016/j.compbiomed.2021.104962 -
Glia Mar 2022The brain requires an adequate supply of oxygen and nutrients to maintain proper function as neuronal activity varies. This is achieved, in part, through neurovascular...
The brain requires an adequate supply of oxygen and nutrients to maintain proper function as neuronal activity varies. This is achieved, in part, through neurovascular coupling mechanisms that mediate local increases in blood flow through the dilation of arterioles and capillaries. The role of astrocytes in mediating this functional hyperemia response is controversial. Specifically, the function of astrocyte Ca signaling is unclear. Cortical arterioles dilate in the absence of astrocyte Ca signaling, but previous work suggests that Ca increases are necessary for capillary dilation. This question has not been fully addressed in vivo, however, and we have reexamined the role of astrocyte Ca signaling in vessel dilation in the barrel cortex of awake, behaving mice. We recorded evoked vessel dilations and astrocyte Ca signaling in response to whisker stimulation. Experiments were carried out on WT and IP3R2 KO mice, a transgenic model where astrocyte Ca signaling is substantially reduced. Compared to WT mice at rest, Ca signaling in astrocyte endfeet contacting capillaries increased by 240% when whisker stimulation evoked running. In contrast, Ca signaling was reduced to 9% of WT values in IP3R2 KO mice. In all three conditions, however, the amplitude of capillary dilation was largely unchanged. In addition, the latency to the onset of astrocyte Ca signaling lagged behind dilation onset in most trials, although a subset of rapid onset Ca events with latencies as short as 0.15 s occurred. In summary, we found that whisker stimulation-evoked capillary dilations occurred independent of astrocyte Ca increases in the cerebral cortex.
Topics: Animals; Astrocytes; Calcium; Calcium Signaling; Capillaries; Cerebral Cortex; Dilatation; Mice
PubMed: 34767261
DOI: 10.1002/glia.24119 -
Hypertension (Dallas, Tex. : 1979) Jul 2022Previous studies suggested blood pressure variability (BPV) might help reveal interactions between blood pressure fluctuation and white matter lesions, and the impact of... (Observational Study)
Observational Study
BACKGROUND
Previous studies suggested blood pressure variability (BPV) might help reveal interactions between blood pressure fluctuation and white matter lesions, and the impact of elevated BPV on white matter hyperintensity (WMH) or cerebral arterial dilation is unclear.
METHODS
This retrospective observational study involved 2634 stroke-free individuals (68.6±11.1 years, 50.3% female), who underwent magnetic resonance imaging and magnetic resonance angiography scans, from a single center in Shanghai, China. Measurements for variability of blood pressure were made based on 7 days blood pressure recordings. WMHs were quantified from T2-FLAIR images and further classified as periventricular WMH or deep WMH. M1 segment of middle cerebral artery dilation was assessed from magnetic resonance angiography images. General linear model was used to examine the associations.
RESULTS
Both increased systolic and diastolic BPV were associated with increased WMH volume (systolic: =0.02 [95% CI, 0.004-0.03], =0.01; diastolic: =0.05 [95% CI, 0.03-0.08], <0.001). Only periventricular WMH was associated with BPV (systolic: =0.02 [95% CI, 0.005-0.04], =0.01; diastolic: =0.06 [95% CI, 0.04-0.09], <0.001). MCA dilation was found in 125 individuals (4.75%). Systolic BPV was associated with MCA dilation only in the hypertensive individuals (=0.11 [95% CI, 0.06-0.17], <0.001). Increased WMH volume was found associated with dilated MCA (=0.17 [95% CI, 0.11-0.23], <0.001).
CONCLUSIONS
Increased BPV might be one of the pathophysiological phenomena involving in the small vessel disease independent of hypertension. Increased BPV might independently contribute to intracranial arterial dilation. Management of BPV might be a target to preserve cerebrovascular wellness.
Topics: Blood Pressure; China; Dilatation; Female; Humans; Hypertension; Magnetic Resonance Imaging; Male; White Matter
PubMed: 35502669
DOI: 10.1161/HYPERTENSIONAHA.122.19269 -
JACC. Cardiovascular Interventions Dec 2019
Topics: Dilatation; Echocardiography, Transesophageal; Humans; Mitral Valve; Mitral Valve Insufficiency; Treatment Outcome
PubMed: 31857017
DOI: 10.1016/j.jcin.2019.10.016 -
American Journal of Otolaryngology 2023Assess if a rigid, image-guided balloon could be used effectively and safely in revision sinus surgery.
PURPOSE
Assess if a rigid, image-guided balloon could be used effectively and safely in revision sinus surgery.
MATERIALS AND METHODS
A prospective, non-randomized, single-arm, multicenter study to assess the safety and device performance of the NuVent™ EM Balloon Sinus Dilation System. Adults with CRS in need of revision sinus surgery were enrolled for balloon sinus dilation of a frontal, sphenoid, or maxillary sinus. The primary device performance endpoint was the ability of the device to (1) navigate to; and (2) dilate tissue in subjects with scarred, granulated, or previously surgically-altered tissue (revision). Safety outcomes included the assessment of any operative adverse events (AEs) directly attributable to the device or for which direct cause could not be determined. A follow-up endoscopy was conducted at 14 days post-treatment for assessment of any AEs. Performance outcomes included the surgeon's ability to reach the target sinus (es) and dilate the ostia. Endoscopic photos were captured for each treated sinus pre- and post-dilation.
RESULTS
At 6 US clinical sites, 51 subjects were enrolled; 1 subject withdrew before treatment due to a cardiac complication from anesthesia. 121 sinuses were treated in 50 subjects. The device performed as expected in 100 % of the 121 treated sinuses, with investigators able to navigate to the treatment area and dilate the sinus ostium without difficulty. Ten AEs were seen in 9 subjects, with 0 related to the device.
CONCLUSION
The targeted frontal, maxillary or sphenoid sinus ostium were safely dilated in every revision subject treated, with no AEs directly attributed to the device.
Topics: Adult; Humans; Dilatation; Prospective Studies; Rhinitis; Maxillary Sinus; Catheterization; Endoscopy; Chronic Disease; Treatment Outcome
PubMed: 36889144
DOI: 10.1016/j.amjoto.2023.103803 -
Ugeskrift For Laeger Jan 2019Symptoms of Eustachian tube dysfunction are frequent and multiple. Therefore, clear definitions and diagnostic criteria are important in order to achieve appropriate... (Review)
Review
Symptoms of Eustachian tube dysfunction are frequent and multiple. Therefore, clear definitions and diagnostic criteria are important in order to achieve appropriate patient flow. So far, there has been a lack of consensus on this subject, but the proposed definitions and diagnostic criteria in this review may aid to achieve this. Tubomanometry is a diagnostic tool to evaluate Eustachian tube function, and balloon dilation of the Eustachian tube can be a helpful treatment in patients with Eustachian tube dysfunction.
Topics: Adult; Catheterization; Dilatation; Ear Diseases; Endoscopy; Eustachian Tube; Humans
PubMed: 30686280
DOI: No ID Found -
European Journal of Vascular and... Jul 2021
Topics: Dilatation; Humans
PubMed: 33431290
DOI: 10.1016/j.ejvs.2020.12.011 -
Optimal Dwelling Time for Ureteral Stents Placed for Passive Dilation after Impassable Ureteroscopy.Urologia Internationalis 2023The aim of the study was to determine the correlation between the dwelling time for a ureteral stent placed for passive dilation after impassable ureteroscopy and...
INTRODUCTION
The aim of the study was to determine the correlation between the dwelling time for a ureteral stent placed for passive dilation after impassable ureteroscopy and success and complications.
METHODS
A retrospective evaluation was made of patients who underwent stent placement after impassable ureteroscopy and a repeat ureteroscopy due to kidney stones. A total of 161 patients were included in the study between 2015 and 2022. Demographic, clinical, preoperative, and perioperative data were collected. Logistic regression analyses were performed on the data showing a significant difference in the univariate analyses performed to determine the predictive factors of ureteroscopy after the stent dwelling period in terms of stone-free status and perioperative complications.
RESULTS
Stone-free status was achieved in 110 (68.3%) of 161 patients, and perioperative complications were observed in 41 (25.4%). Factors that affected the stone-free status were determined as the dwelling time and the S-ReSC score, while factors affecting perioperative complications were the stent dwelling time and the operation time. The stone-free rates were observed to increase from 46.4% in the first 2 weeks to 72.9% after the 2nd week, an increase of 1.5-fold. Perioperative complications were determined at the rate of 17.5% during the first 5 weeks and increased 2.1-fold to 37.5% after the 5th week.
CONCLUSION
It can be recommended that great care is taken during the stent dwelling period and ureteroscopy should be performed within 5 weeks (14-35 days) but no earlier than 2 weeks, so as not to affect the success of the procedure.
Topics: Humans; Ureteroscopy; Ureteral Calculi; Dilatation; Retrospective Studies; Postoperative Complications; Stents; Treatment Outcome
PubMed: 37454649
DOI: 10.1159/000531482 -
BMC Gastroenterology Jun 2023Benign choledochojejunal anastomotic stricture (CJS) is a common complication of pancreaticoduodenectomy and choledochojejunostomy. CJS is generally treated with balloon...
Long- and short-term outcomes of balloon dilation for benign choledochojejunal anastomotic stricture using balloon endoscopy-assisted ERCP: a multi-center retrospective cohort study.
BACKGROUND
Benign choledochojejunal anastomotic stricture (CJS) is a common complication of pancreaticoduodenectomy and choledochojejunostomy. CJS is generally treated with balloon dilation, using balloon endoscopy-assisted endoscopic retrograde cholangiopancreatography (BE-ERCP); however, its long- and short-term outcomes have not been fully evaluated. Therefore, we evaluated the treatment outcomes of balloon dilation with BE-ERCP for CJS.
METHODS
We retrospectively analyzed 40 patients who had undergone balloon dilation with BE-ERCP for CJS between January 2009 and December 2022. The primary outcomes were technical and clinical success, and adverse event rates of balloon dilation using BE-ERCP for CJS. The secondary outcomes were long-term treatment outcomes for CJS recurrence, and evaluation of risk factors for recurrence.
RESULT
Technical and clinical success rates were 93% (37/40) and 100% (37/37), respectively. CJS recurrence occurred in 32% (20/37). No procedure-related adverse events were observed. The significant risk factors of CJS after balloon dilation were its early occurrence after surgery (unit hazard ratio [HR] for month, 0.87; 95% confidence interval [CI], 0.76-0.99; p-value = 0.04) and residual waist during balloon dilation (HR, 5.46; 95% CI, 1.18-25.1; p-value = 0.03). Receiver operating characteristic curve analysis of time from surgery to balloon dilation revealed an area under the curve of 0.80 (95% CI, 0.65-0.94) and the cut-off value was 13.2 months.
CONCLUSION
Treatment of CJS with balloon dilation was effective, although CJS recurrence occurred in one-third of the patients. The risk factors for recurrence were early occurrence of CJS after surgery and remaining waist circumference during balloon dilation.
Topics: Humans; Cholangiopancreatography, Endoscopic Retrograde; Retrospective Studies; Constriction, Pathologic; Dilatation; Neoplasm Recurrence, Local; Treatment Outcome
PubMed: 37264302
DOI: 10.1186/s12876-023-02830-3