Assessment of feto-placental oxygenation and perfusion in a rat model of placental insufficiency using T2* mapping and 3D dynamic contrast-enhanced MRI.

Introduction: Placental insufficiency may lead to preeclampsia and fetal growth restriction. There is no cure for placental insufficiency, emphasizing the need for monitoring fetal and placenta health. Current monitoring methods are limited, underscoring the necessity for imaging techniques to evaluate fetal-placental perfusion and oxygenation.

Analysis of the fluorescent properties of vaginal fluid upon ageing.

Detection and identification of body fluids are crucial aspects of forensic investigations, aiding in crime scene reconstructions and providing important leads. Although many methods have been developed for these purposes, no method is currently in use in the forensic field that allows rapid, non-contact detection and identification of vaginal fluids directly at the crime scene. The development of such technique is mainly challenged by the complex chemistry of the constituents, which can differ between donors and exhibits changes based on woman's menstrual cycle.

Home-Use Hyaluronic Acid Jet Injectors: Unreliable and Unsafe.

Background: Needle-free hyaluronic acid (HA) jet injectors are gaining popularity for rejuvenation treatment. The devices are widely available online and are used for self-injection or in beauty salons by nonphysicians. However, little is known about their performance and safety.

Effect of long-term antihypertensive treatment on cerebrovascular structure and function in hypertensive rats.

Midlife hypertension is an important risk factor for cognitive impairment and dementia, including Alzheimer's disease. We investigated the effects of long-term treatment with two classes of antihypertensive drugs to determine whether diverging mechanisms of blood pressure lowering impact the brain differently. Spontaneously hypertensive rats (SHR) were either left untreated or treated with a calcium channel blocker (amlodipine) or beta blocker (atenolol) until one year of age.

A comparison of myocardial magnetic resonance extracellular volume mapping at 3 T against histology of tissue collagen in severe aortic valve stenosis and obstructive hypertrophic cardiomyopathy.

Objective: Quantitative extracellular volume fraction (ECV) mapping with MRI is commonly used to investigate in vivo diffuse myocardial fibrosis. This study aimed to validate ECV measurements against ex vivo histology of myocardial tissue samples from patients with aortic valve stenosis or hypertrophic cardiomyopathy.

Materials And Methods: Sixteen patients underwent MRI examination at 3 T to acquire native T maps and post-contrast T maps after gadobutrol administration, from which hematocrit-corrected ECV maps were estimated.

Late Gadolinium Enhancement Cardiovascular Magnetic Resonance Assessment of Substrate for Ventricular Tachycardia With Hemodynamic Compromise.

The majority of data regarding tissue substrate for post myocardial infarction (MI) VT has been collected during hemodynamically tolerated VT, which may be distinct from the substrate responsible for VT with hemodynamic compromise (VT-HC). This study aimed to characterize tissue at diastolic locations of VT-HC in a porcine model. Late Gadolinium Enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging was performed in eight pigs with healed antero-septal infarcts.

Altered brain fluid management in a rat model of arterial hypertension.

Background: Proper neuronal function is directly dependent on the composition, turnover, and amount of interstitial fluid that bathes the cells. Most of the interstitial fluid is likely to be derived from ion and water transport across the brain capillary endothelium, a process that may be altered in hypertension due to vascular pathologies as endothelial dysfunction and arterial remodelling. In the current study, we investigated the effects of hypertension on the brain for differences in the water homeostasis.

Abnormal sodium and water homeostasis in mice with defective heparan sulfate polymerization.

Glycosaminoglycans in the skin interstitium and endothelial surface layer have been shown to be involved in local sodium accumulation without commensurate water retention. Dysfunction of heparan sulfate glycosaminoglycans may therefore disrupt sodium and water homeostasis. In this study, we investigated the effects of combined heterozygous loss of heparan sulfate polymerization genes (exostosin glycosyltransferase 1 and 2; Ext1+/-Ext2+/-) on sodium and water homeostasis.

Extravasation of Microspheres in a Rat Model of Silent Brain Infarcts.

Background and Purpose- We developed a rat model of silent brain infarcts based on microsphere infusion and investigated their impact on perfusion and tissue damage. Second, we studied the extent and mechanisms of perfusion recovery. Methods- At day 0, 15 µm fluorescent microspheres were injected into the right common carotid artery of F344 rats.

Optical coherence tomography to detect acute esophageal radiation-induced damage in mice: A validation study.

Radiation therapy for patients with non-small-cell lung cancer is hampered by acute radiation-induced toxicity in the esophagus. This study aims to validate that optical coherence tomography (OCT), a minimally invasive imaging technique with high resolution (~10 μm), is able to visualize and monitor acute radiation-induced esophageal damage (ARIED) in mice. We compare our findings with histopathology as the gold standard.

Blood-brain and blood-cerebrospinal fluid barrier permeability in spontaneously hypertensive rats.

Background: Hypertension is an important risk factor for cerebrovascular disease, including stroke and dementia. Both in humans and animal models of hypertension, neuropathological features such as brain atrophy and oedema have been reported. We hypothesised that cerebrovascular damage resulting from chronic hypertension would manifest itself in a more permeable blood-brain barrier and blood-cerebrospinal fluid barrier.

Nur77 protects against adverse cardiac remodelling by limiting neuropeptide Y signalling in the sympathoadrenal-cardiac axis.

Aims: Cardiac remodelling and heart failure are promoted by persistent sympathetic activity. We recently reported that nuclear receptor Nur77 may protect against sympathetic agonist-induced cardiac remodelling in mice. The sympathetic co-transmitter neuropeptide Y (NPY) is co-released with catecholamines and is a known cardiac modulator and predictor of heart failure mortality.

Thrombospondin-4 mediates cardiovascular remodelling in angiotensin II-induced hypertension.

Thrombospondin 4 (TSP-4) expression is induced in the heart and vasculature under pathological conditions, including myocardial infarction, myocardial pressure overload, and hypertension. TSP-4 is linked to remodelling processes, where it may affect extracellular matrix protein organization. In previous work, we studied the role of TSP-4 in small arteries during hypertension using Ang II-treated Thrombospondin 4 knockout (Thbs4) mice.

Paravascular spaces at the brain surface: Low resistance pathways for cerebrospinal fluid flow.

Clearance of waste products from the brain is of vital importance. Recent publications suggest a potential clearance mechanism via paravascular channels around blood vessels. Arterial pulsations might provide the driving force for paravascular flow, but its flow pattern remains poorly characterized.

Enhanced interstitial fluid drainage in the hippocampus of spontaneously hypertensive rats.

Hypertension is associated with cognitive decline and various forms of dementia, including Alzheimer's disease. In animal models of hypertension, many of Alzheimer's disease characteristics are recapitulated, including brain atrophy, cognitive decline, amyloid β accumulation and blood brain barrier dysfunction. Removal of amyloid β and other waste products depends in part on clearance via the brain interstitial fluid (ISF).

Optimization of Vascular Casting for Three-Dimensional Fluorescence Cryo-Imaging of Collateral Vessels in the Ischemic Rat Hindlimb.

Development of collateral vessels, arteriogenesis, may protect against tissue ischemia, however, quantitative data on this process remain scarce. We have developed a technique for replicating the entire arterial network of ischemic rat hindlimbs in three dimensions (3D) based on vascular casting and automated sequential cryo-imaging. Various dilutions of Batson's No.

Paravascular channels, cisterns, and the subarachnoid space in the rat brain: A single compartment with preferential pathways.

Recent evidence suggests an extensive exchange of fluid and solutes between the subarachnoid space and the brain interstitium, involving preferential pathways along blood vessels. We studied the anatomical relations between brain vasculature, cerebrospinal fluid compartments, and paravascular spaces in male Wistar rats. A fluorescent tracer was infused into the cisterna magna, without affecting intracranial pressure.

Clearance from the mouse brain by convection of interstitial fluid towards the ventricular system.

Background: In the absence of a true lymphatic system in the brain parenchyma, alternative clearance pathways for excess fluid and waste products have been proposed. Suggested mechanisms for clearance implicate a role for brain interstitial and cerebrospinal fluids. However, the proposed direction of flow, the anatomical structures involved, and the driving forces are controversial.

Gene Expression and MicroRNA Expression Analysis in Small Arteries of Spontaneously Hypertensive Rats. Evidence for ER Stress.

Small arteries are known to develop functional and structural alterations in hypertension. However, the mechanisms of this remodeling are not fully understood. We hypothesized that altered gene expression is associated with the development of hypertension in mesenteric arteries of spontaneously hypertensive rats (SHR).

Cerebral Artery Remodeling in Rodent Models of Subarachnoid Hemorrhage.

Vasospasm is known to contribute to delayed cerebral ischemia following subarachnoid hemorrhage (SAH). We hypothesized that vasospasm initiates structural changes within the vessel wall, possibly aggravating ischemia and leading to resistance to vasodilator treatment. We therefore investigated the effect of blood on cerebral arteries with respect to contractile activation and vascular remodeling.

Heterogeneity in arterial remodeling among sublines of spontaneously hypertensive rats.

Objectives: Spontaneously hypertensive rats (SHR) have been used frequently as a model for human essential hypertension. However, both the SHR and its normotensive control, the Wistar Kyoto rat (WKY), consist of genetically different sublines. We tested the hypothesis that the pathophysiology of vascular remodeling in hypertension differs among rat sublines.

Oxidation monitoring by fluorescence spectroscopy reveals the age of fingermarks.

No forensic method exists that can reliably estimate the age of fingermarks found at a crime scene. Information on time passed since fingermark deposition is desired as it can be used to distinguish between crime related and unrelated fingermarks and to support or refute statements made by the fingermark donors. We introduce a non-contact method that can estimate the age of fingermarks.

Smooth muscle contractile plasticity in rat mesenteric small arteries: sensitivity to specific vasoconstrictors, distension and inflammatory cytokines.

Small artery remodeling may involve a shift in the diameter-dependent force generating capacity of smooth muscle cells (SMC). We tested to what extent and under which conditions such contractile plasticity occurs. Rat mesenteric arteries were mounted on isometric myographs.