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Indian Journal of Thoracic and... Jul 2024[This corrects the article DOI: 10.1007/s12055-024-01734-5.].
[This corrects the article DOI: 10.1007/s12055-024-01734-5.].
PubMed: 38919187
DOI: 10.1007/s12055-024-01745-2 -
Scientific Reports Jun 2024Cerebrovascular resistance (CVR) regulates blood flow in the brain, but little is known about the vascular resistances of the individual cerebral territories. We present...
Cerebrovascular resistance (CVR) regulates blood flow in the brain, but little is known about the vascular resistances of the individual cerebral territories. We present a method to calculate these resistances and investigate how CVR varies in the hemodynamically disturbed brain. We included 48 patients with stroke/TIA (29 with symptomatic carotid stenosis). By combining flow rate (4D flow MRI) and structural computed tomography angiography (CTA) data with computational fluid dynamics (CFD) we computed the perfusion pressures out from the circle of Willis, with which CVR of the MCA, ACA, and PCA territories was estimated. 56 controls were included for comparison of total CVR (tCVR). CVR were 33.8 ± 10.5, 59.0 ± 30.6, and 77.8 ± 21.3 mmHg s/ml for the MCA, ACA, and PCA territories. We found no differences in tCVR between patients, 9.3 ± 1.9 mmHg s/ml, and controls, 9.3 ± 2.0 mmHg s/ml (p = 0.88), nor in territorial CVR in the carotid stenosis patients between ipsilateral and contralateral hemispheres. Territorial resistance associated inversely to territorial brain volume (p < 0.001). These resistances may work as reference values when modelling blood flow in the circle of Willis, and the method can be used when there is need for subject-specific analysis.
Topics: Humans; Male; Female; Cerebrovascular Circulation; Hydrodynamics; Vascular Resistance; Middle Aged; Aged; Magnetic Resonance Imaging; Stroke; Carotid Stenosis; Hemodynamics; Computed Tomography Angiography; Circle of Willis; Blood Flow Velocity; Brain
PubMed: 38918589
DOI: 10.1038/s41598-024-65431-4 -
Neurotherapeutics : the Journal of the... Jun 2024The precise oxygen content thresholds of ischemic deep parenchymal (OCIDP) and that in cortical microcirculation (OCCM), which leads to ischemic penumbra converting into...
The precise oxygen content thresholds of ischemic deep parenchymal (OCIDP) and that in cortical microcirculation (OCCM), which leads to ischemic penumbra converting into the infarcted core, remain uncertain. This study employed an invasive fiber-optic oxygen meter and a newly developed oxygen-responsive probe called RuA-Cy5-rtPA (RC-rtPA) based on recombinant tissue-type plasminogen activator (rtPA) to examine the oxygen content thresholds. A mouse model of middle cerebral artery occlusion was generated and animals were randomly divided into a sham, 24-h reperfusion after 3-h ischemia (IR 3-h), and IR 6-h groups, all of which were sacrificed following reperfusion. Stroke severity was evaluated based on the infarction area, neurological symptoms, microcirculation perfusion, and microemboli in microcirculation. OCIDP was characterized based on its extent and distribution, whereas OCCM was measured using RC-rtPA. During ischemia, stroke severity escalation manifested as increasing infarction area, severe neurologic symptoms, and poorer microcirculation perfusion with more microthrombi depositions. OCIDP presented rapid decline following artery occlusion along with a gradual increase in the hypoxic area. Within 3 h following ischemia induction, the ischemic tissue that experienced hypoxia could be rescued, and this reversibility would disappear after 6 h. Within 6 h, OCCM continued to decrease. A significant decrease in oxygen content in cortical venules and cortical parenchyma was observed. These findings assist in establishing the extent of the ischemic penumbra at the microcirculation level and offer a foundation for assessing the ischemic penumbra that could respond positively to reperfusion therapy beyond the typical time window.
PubMed: 38918128
DOI: 10.1016/j.neurot.2024.e00387 -
Biomedicine & Pharmacotherapy =... Jun 20245-HT clearance, commonly mediated by transporters in the uptake-1 and uptake-2 families, has been linked to 5-HT receptor's action on behaviors. Since no specific...
5-HT clearance, commonly mediated by transporters in the uptake-1 and uptake-2 families, has been linked to 5-HT receptor's action on behaviors. Since no specific transporters identified yet, effects of serotonin transporter (SERT) and organic cation transporter (OCTs) on 5-HT-elicited immobility phenotype, and 5-HT and HIS uptake were then investigated. Intraperitoneal injections of SERT inhibitor fluoxetine (FLX) and/or OCTs inhibitor decynium (D22) were used prior to local perfusion of 5-HT agonist CP93129 into the ventral hippocampus to measure immobility times in the FST and TST, to measure 5-HT uptake efficiencies and HIS uptake efficiencies derived from linear regressions using the transient no-net-flux quantitative microdialysis in C57BL/6 mice. Exogenous 5-HT and HIS uptake were measured following incubation of FLX and/or D22 with CP93129 in the RBL-2H3 cells. Moreover, surface membrane levels of SERT and OCT were detected in response to CP93129. Local CP93129 prolonged immobility times, which were attenuated following pretreatment of either inhibitor. Local CP93129 lowered the slopes obtained from the lineal regressions for 5-HT and HIS (slope is reciprocal to uptake efficiency), which were then weakened following pretreatment of either inhibitor. Similar findings were obtained following CP93129 incubation, and co-incubation of CP93129 with either inhibitor in the RBL-2H3. Moreover, CP93129 dose-dependently moved SERT and OCT3 in the cytosol to the surface membrane. Both SERT and OCT are the target effectors mediating 5-HT regulation of immobility time and 5-HT uptake, OCT mediates 5-HT regulation of HIS uptake. Their underlying signal transductions need to be further explored.
PubMed: 38917762
DOI: 10.1016/j.biopha.2024.117017 -
Cureus May 2024Peripheral artery disease (PAD) is the buildup of calcium and fatty deposits in the arterial walls (atherosclerosis). This is an important clinical issue, specifically...
Peripheral artery disease (PAD) is the buildup of calcium and fatty deposits in the arterial walls (atherosclerosis). This is an important clinical issue, specifically in cases with multilevel lesions. A patient underwent sequential angioplasty treatment for major PAD, which was characterized by multilevel lesions affecting both the infrapopliteal arteries. The proximal vessels and infrapopliteal vessels are mostly observed to be affected by PAD, thus the patient likely has PAD localized to the lower leg. In the femoropopliteal segment, lower extremity artery or aortic atherosclerotic occlusive disease can lead to significant outcomes. Severe claudication and pain during rest in both legs were observed in a patient with a history of hypertension and diabetes mellitus. With an angiography, the superficial femoral, popliteal, and tibial arteries have been shown to have major stenoses and occlusions. A progressive treatment was used because of the complexity of the lesions initiating with endovascular revascularization of the superficial femoral artery. The popliteal and tibial arteries were then repaired with angioplasty and stent placement. After the treatment, the patient's symptoms significantly improved, including elimination of their rest discomfort and claudication. Measurements of the ankle-brachial index (ABI) indicated that the affected limbs' perfusion was refined. Six months later, a follow-up angiography revealed intact vessels with no restenosis. This case report shows the successful outcome of recurrent angioplasty in curing complicated multilevel PAD, giving symptomatic relief and maintaining limb perfusion. This research is required to assess the long-term outcomes and longevity of this kind of treatment in patient populations that are comparable to others.
PubMed: 38915963
DOI: 10.7759/cureus.60982 -
Clinical Kidney Journal Jun 2024The aim of this work was to create and evaluate a preoperative non-contrast-enhanced (CE) magnetic resonance imaging (MRI)/angiography (MRA) protocol to assess renal...
BACKGROUND
The aim of this work was to create and evaluate a preoperative non-contrast-enhanced (CE) magnetic resonance imaging (MRI)/angiography (MRA) protocol to assess renal function and visualize renal arteries and any abnormalities in potential living kidney donors.
METHODS
In total, 28 subjects were examined using scintigraphy to determine renal function. In addition, 3D-pseudocontinuous arterial spin labeling (pCASL), a 2D-non-CE electrocardiogram-triggered radial quiescent interval slice-selective (QISS-MRA), and 4D-CE time-resolved angiography with interleaved stochastic trajectories (CE-MRA) were performed to assess renal perfusion, visualize renal arteries and detect any abnormalities. Two glomerular filtration rates [described by Gates (GFR) and according to the Chronic Kidney Disease Epidemiology Collaboration formula (GFR)]. The renal volumes were determined using both MRA techniques.
RESULTS
The mean value of regional renal blood flow (rRBF) on the right side was significantly higher than that on the left. The agreements between QISS-MRA and CE-MRA concerning the assessment of absence or presence of an aberrant artery and renal arterial stenosis were perfect. The mean renal volumes measured in the right kidney with QISS-MRA were lower than the corresponding values of CE-MRA. In contrast, the mean renal volumes measured in the left kidney with both MRA techniques were similar. The correlation between the GFR and rRBF was compared in the same manner as that between GFR and rRBF.
CONCLUSION
The combination of pCASL and QISS-MRA constitute a reliable preoperative protocol with a total measurement time of <10 min without the potential side effects of gadolinium-based contrast agents or radiation exposure.
PubMed: 38915436
DOI: 10.1093/ckj/sfae101 -
Vascular Specialist International Jun 2024Paradoxical embolism through the foramen ovale is a rare and devastating event requiring urgent treatment. Herein, we present the case of a 23-year-old male who...
Paradoxical embolism through the foramen ovale is a rare and devastating event requiring urgent treatment. Herein, we present the case of a 23-year-old male who presented with a pulmonary embolism complicated by a left renal artery paradoxical embolism. Urgent vacuum-assisted thrombo-aspiration restored normal perfusion of the left kidney within 5 hours. The patient had a patent foramen ovale and heterozygous thrombophilia. However, a radioisotopic scan performed 2 years later revealed an unexpected decrease in left renal perfusion. Therefore, despite the angiographic success, functional evaluation using a renal scan should be performed to assess renal function.
PubMed: 38915224
DOI: 10.5758/vsi.240022 -
Journal of Korean Neurosurgical Society Jun 2024Hemifacial spasm (HFS) is treated by a surgical procedure called microvascular decompression (MVD). However, HFS re-appearing phenomenon after surgery, presenting as...
Prediction of hemifacial spasm re-appearing phenomenon after microvascular decompression surgery in patients with hemifacial spasm using dynamic susceptibility contrast perfusion MRI.
OBJECTIVE
Hemifacial spasm (HFS) is treated by a surgical procedure called microvascular decompression (MVD). However, HFS re-appearing phenomenon after surgery, presenting as early recurrence, is experienced by some patients after MVD. Dynamic susceptibility contrast (DSC) perfusion MRI and two analytical methods: receiver operating characteristic (ROC) curve and machine learning, were used to predict early recurrence in this study.
METHODS
This study enrolled sixty patients who underwent MVD for HFS. They were divided into two groups: Group A consisted of 32 patients who had early recurrence, and Group B consisted of 28 patients who had no early recurrence of HFS. DSC perfusion MRI was undergone by all patients before the surgery to obtain the several parameters. ROC curve and machine learning methods were used to predict early recurrence using these parameters.
RESULTS
Group A had significantly lower relative cerebral blood flow (rCBF) than Group B in most of the selected brain regions, as shown by the region-of-interest (ROI)-based analysis. By combining three extraction fraction (EF) values at middle temporal gyrus, posterior cingulate, and brainstem, with age, using naive Bayes machine learning method, the best prediction model for early recurrence was obtained. This model had an area under the curve (AUC) value of 0.845.
CONCLUSION
By combining EF values with age or sex using machine learning methods, DSC perfusion MRI can be used to predict early recurrence before MVD surgery. This may help neurosurgeons to identify patients who are at risk of HFS recurrence and provide appropriate postoperative care.
PubMed: 38915211
DOI: 10.3340/jkns.2024.0055 -
Scientific Reports Jun 2024The rapid perfusion of cerebral arteries leads to a significant increase in intracranial blood volume, exposing patients with traumatic brain injury to the risk of...
Assessment of cerebrovascular alterations induced by inflammatory response and oxidative-nitrative stress after traumatic intracranial hypertension and a potential mitigation strategy.
The rapid perfusion of cerebral arteries leads to a significant increase in intracranial blood volume, exposing patients with traumatic brain injury to the risk of diffuse brain swelling or malignant brain herniation during decompressive craniectomy. The microcirculation and venous system are also involved in this process, but the precise mechanisms remain unclear. A physiological model of extremely high intracranial pressure was created in rats. This development triggered the TNF-α/NF-κB/iNOS axis in microglia, and released many inflammatory factors and reactive oxygen species/reactive nitrogen species, generating an excessive amount of peroxynitrite. Subsequently, the capillary wall cells especially pericytes exhibited severe degeneration and injury, the blood-brain barrier was disrupted, and a large number of blood cells were deposited within the microcirculation, resulting in a significant delay in the recovery of the microcirculation and venous blood flow compared to arterial flow, and this still persisted after decompressive craniectomy. Infliximab is a monoclonal antibody bound to TNF-α that effectively reduces the activity of TNF-α/NF-κB/iNOS axis. Treatment with Infliximab resulted in downregulation of inflammatory and oxidative-nitrative stress related factors, attenuation of capillary wall cells injury, and relative reduction of capillary hemostasis. These improved the delay in recovery of microcirculation and venous blood flow.
Topics: Animals; Oxidative Stress; Rats; Intracranial Hypertension; Male; Tumor Necrosis Factor-alpha; Inflammation; Microcirculation; Cerebrovascular Circulation; Rats, Sprague-Dawley; Brain Injuries, Traumatic; Infliximab; Disease Models, Animal; Blood-Brain Barrier; Reactive Oxygen Species; Reactive Nitrogen Species; Microglia
PubMed: 38914585
DOI: 10.1038/s41598-024-64940-6 -
Resuscitation Plus Sep 2024Minimizing cardiac arrest times is critical in extracorporeal cardiopulmonary resuscitation (ECPR). Pre-primed extra corporeal membrane oxygenator (ECMO) is used for...
AIM
Minimizing cardiac arrest times is critical in extracorporeal cardiopulmonary resuscitation (ECPR). Pre-primed extra corporeal membrane oxygenator (ECMO) is used for this, but knowledge is limited to experimental studies. We prospectively investigated oxygenator function and sterility in dry plus wet pre-priming in a clinical setting.
METHODS
This prospective clinical study included 107 ECMO circuits used at Sahlgrenska University Hospital between October 2019 and December 2021. Circuits underwent dry set-up, followed by wet priming when the previous wet-primed circuit was used. Sterility was assessed by culturing the priming solution. Oxygenator function parameters, including sweep gas flow, fraction of oxygen (FiO), and oxygenator resistance, were analyzed at ECMO initiation and during treatment using linear mixed models.
RESULTS
Median total set-up time was 14 days (range 0-97), with a median wet prime time of 6 days (range 0-57). 103 of 105 circuits with culture results were negative, two showed bacterial growth (coagulase-negative staphylococci and ). Wet prime time did not significantly affect initial oxygenator function. Oxygenator resistance and FiO increased during ECMO treatment (0.035 mmHg/L min (95 % confidence interval (CI) 0.015-0.055) < 0.001, and 2.19 % (0.92-3.46) = 0.009), but these changes were unrelated to wet prime time.
CONCLUSION
Wet pre-priming of ECMO circuits for up to 57 days did not affect oxygenator function. The low incidence of bacterial growth (1.9 %) suggests that pre-primed ECMO generally maintain sterility and can facilitate rapid ECPR initiation. However, bacterial growth highlights the need for caution in non-urgent cases. Culturing the circuit at initiation can mitigate this risk.
PubMed: 38912528
DOI: 10.1016/j.resplu.2024.100680