Effects of Hemorrhagic Shock and Rhabdomyolysis on Renal Microcirculation, Oxygenation, and Function in a Female Swine Model.

Background: Hemorrhagic shock (HS) and rhabdomyolysis (RM) are two important risk factors for acute kidney injury after severe trauma; however, the effects of the combination of RM and HS on kidney function are unknown. The purpose of this study was to determine the impact of RM and HS on renal function, oxygenation, perfusion, and morphology in a pig model.

Methods: Forty-seven female pigs were divided into five groups: sham, RM, HS, HS and moderate RM (RM4/HS), and HS and severe RM (RM8/HS).

Intra-arterial injection of particulate corticosteroids: mechanism of injury.

Mechanism of neurologic complications after epidural spinal injections (ESI) of particulate steroids at the cervical spine include intrathecal injection, epidural hematoma, direct spinal cord injury, and brain stem or cord infarction due to an arterial spasm or inadvertent intra-arterial injection of particulate steroids. At the lumbar spine, there is evidence that a spinal cord infarction secondary to an inadvertent intra-arterial injection of particulate steroids through a transforaminal approach is the leading mechanism.Variations in the arterial supply of the spinal cord help to understand how a lumbar ESI may lead to a spinal cord infarction at the thoracic level.

Renal Microcirculation and Function in a Pig Model of Hemorrhagic Shock Resuscitation with Norepinephrine.

Norepinephrine (NE) is commonly used in combination with fluid during resuscitation of hemorrhagic shock, but its impact on kidney microcirculation, oxygenation, and function is still unknown in this setting. During hemorrhagic shock resuscitation, does a combination of fluid and NE affect kidney oxygenation tension, kidney microcirculatory perfusion, and 48-hour kidney function, as compared with fluid alone? Hemorrhagic shock was induced in 24 pigs, and 8 pigs were included as a sham group. Resuscitation of hemorrhagic shock was performed, using a closed-loop device, either by fluid alone (0.

De novo generation in an in vivo rat model and biomechanical characterization of autologous transplants for ligament and tendon reconstruction.

Background: Surgical reconstruction of ligaments and tendons is frequently required in clinical practice. The commonly used autografts, allografts, or synthetic transplants present limitations in terms of availability, biocompatibility, cost, and mechanical properties that tissue bioengineering aims to overcome. It classically combines an exogenous extracellular matrix with cells, but this approach remains complex and expensive.

Combinatorial therapy with two pro-coagulants and one osmotic agent reduces the extent of the lesion in the acute phase of spinal cord injury in the rat.

Background: Spinal cord injury (SCI) is a complex disease that leads to a motor, sensitive, and vegetative impairment. So far, single therapies are ineffective for treating SCI in humans and a multifactorial therapeutic approach may be required. The aim of this work was to assess the effect of a triple therapy (TT) associating two pro-coagulant therapies (tranexamic acid and fibrinogen) with an anti-edema therapy (hypertonic saline solution), on the extent of the lesion 24 h post-injury.

Pronation and supination of the hand: Anatomy and biomechanics.

Proper functioning of the hand relies on its capacity to rotate and point the palm upward (i.e. supination) or downward (i.

Cadaveric assessment of a 3D-printed aiming device for implantation of a hinged elbow external fixator.

Introduction: Proper implantation of a hinged external elbow fixator (HEEF) is demanding since it requires precise alignment between the flexion-extension's and HEEF's axis. In order to optimize this alignment, we have developed a 3D-printed aiming device. The primary goal of the study was to compare the aiming device-based technique with the conventional pin technique.

Deleterious Effects of Intra-arterial Administration of Particulate Steroids on Microvascular Perfusion in a Mouse Model.

Purpose To determine the in vivo effects of several particulate steroids on microvascular perfusion by using intravital microscopy in a mice model and to investigate the in vitro interactions between these particulate steroids and red blood cells (RBCs). Materials and Methods The study was conducted in agreement with the guidelines of the National Committee of Ethic Reflection on Animal Experimentation. By using intravital microscopy of mouse cremaster muscle, the in vivo effects of several particulate steroids on microvascular perfusion were assessed.

Contrast enhanced ultrasound imaging for assessment of spinal cord blood flow in experimental spinal cord injury.

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an important target for neuroprotective therapies.

Effects of adenosine monophosphate used in combination with L-arginine on female rabbit corpus cavernosum tissue.

Introduction: Sexual dysfunction is significantly more prevalent in women than in men. However, to date, no satisfactory oral treatment is yet available.

Aim: The aim of this study was to study the effects of adenosine monophosphate (AMP) alone or its combination with L-Arginine on the relaxation of the female rabbit corpus cavernosum.

Effect of norepinephrine on spinal cord blood flow and parenchymal hemorrhage size in acute-phase experimental spinal cord injury.

Purpose: In the acute phase of spinal cord injury (SCI), ischemia and parenchymal hemorrhage are believed to worsen the primary lesions induced by mechanical trauma. To minimize ischemia, keeping the mean arterial blood pressure above 85 mmHg for at least 1 week is recommended, and norepinephrine is frequently administered to achieve this goal. However, no experimental study has assessed the effect of norepinephrine on spinal cord blood flow (SCBF) and parenchymal hemorrhage size.

Rat model of spinal cord injury preserving dura mater integrity and allowing measurements of cerebrospinal fluid pressure and spinal cord blood flow.

Purposes: Cerebrospinal fluid (CSF) pressure elevation may worsen spinal cord ischaemia after spinal cord injury (SCI). We developed a rat model to investigate relationships between CSF pressure and spinal cord blood flow (SCBF).

Methods: Male Wistar rats had SCI induced at Th10 (n = 7) or a sham operation (n = 10).

Interleukin 10 antioxidant effect decreases leukocytes/endothelial interaction induced by tumor necrosis factor α.

Little is known about the endothelial mechanisms involved in the anti-inflammatory effects of interleukin 10 (IL-10). The goal of this study was to evaluate the effects of IL-10 on endothelial oxidative stress and endothelial inflammation induced by tumor necrosis factor α (TNF-α). Production of reactive oxygen species (ROS) in perfused human umbilical vein endothelial cells (HUVECs) was studied by fluorescent microscopy using dichlorodihydrofluorescein diacetate.

Real-time and spatial quantification using contrast-enhanced ultrasonography of spinal cord perfusion during experimental spinal cord injury.

Study Design: Experimental study in male Wistar rats.

Objective: To quantify temporal and spatial changes simultaneously in spinal cord blood flow and hemorrhage during the first hour after spinal cord injury (SCI), using contrast-enhanced ultrasonography (CEU).

Summary Of Background Data: Post-traumatic ischemia and hemorrhage worsen the primary lesions induced by SCI.

Dexrazoxane protects the heart from acute doxorubicin-induced QT prolongation: a key role for I(Ks).

Introduction: Doxorubicin, an anthracycline widely used in the treatment of a broad range of tumours, causes acute QT prolongation. Dexrazoxane has been shown to prevent the QT prolongation induced by another anthracycline, epirubicin, but has not yet been reported to prevent that induced by doxorubicin. Thus, the present study was designed to test whether the acute QT effects induced by doxorubicin could be blocked by dexrazoxane and to explore the mechanism.

In vivo reactive oxygen species production induced by ischemia in muscle arterioles of mice: involvement of xanthine oxidase and mitochondria.

Reactive oxygen species (ROS) participate in tissue injury after ischemia-reperfusion. Their implication in leukocyte adherence and increase in permeability at the venular side of the microcirculation have been reported, but very little is known about ROS production in arterioles. The objective of this work was to evaluate, in the arteriole wall in vivo, the temporal changes in superoxide anion production during ischemia and reperfusion and to identify the source of this production.

Characteristic features of in vivo skin microvascular reactivity in CADASIL.

CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is caused by mutations in the Notch3 receptor expressed at the surface of vascular smooth muscle cells. The functional consequences of the disease at the peripheral microcirculation level are incompletely elucidated. In this study, we aimed to assess, in vivo, the endothelium-dependent and independent vasodilation of the skin microvasculature in CADASIL patients.

Reactive oxygen species production by mitochondria in endothelial cells exposed to reoxygenation after hypoxia and glucose depletion is mediated by ceramide.

In endothelium, reoxygenation after hypoxia (H/R) has been shown to induce production of reactive oxygen species (ROS) by complex III of the mitochondrial respiratory chain. The purpose of the present study was to test the involvement of ceramide in this phenomenon. Human umbilical vein endothelial cells underwent 2 h of hypoxia (PO2, approximately 20 mmHg) without glucose and 1 h of reoxygenation (PO2, approximately 120 mmHg) with glucose.

Fibered confocal fluorescence microscopy (Cell-viZio) facilitates extended imaging in the field of microcirculation. A comparison with intravital microscopy.

This study investigated the capability of fibered confocal fluorescence microscopy (FCFM) to provide in vivo microvascular observations. FCFM is specifically designed for in vivo in situ observation thanks to a probe composed of a fiber bundle and micro-optics having a diameter as small as 650 microm. In the first part of the study, we compared the main characteristics of FCFM with those of intravital fluorescence microscopy (IFM).

Reoxygenation after hypoxia and glucose depletion causes reactive oxygen species production by mitochondria in HUVEC.

In hemorrhagic shock, local hypoxia is present and followed by reoxygenation during the therapeutic process. In endothelium, reactive oxygen species (ROS) have been identified as a cause of inflammatory reactions and tissular lesions in ischemic territory during reoxygenation. This study was designed to identify the enzymatic mechanisms of ROS formation during reoxygenation after hypoxia.

Interaction between nitric oxide and prostanoids in arterioles of rat cremaster muscle in vivo.

We studied in vivo interactions of nitric oxide (NO), oxidative stress, and prostanoids derived from the cyclooxygenase pathway in the arterioles studied by intravital microscopy in peripheral muscle. Topical administration of NO synthase (NOS) inhibitor Nomega-nitro-l-arginine (l-NNA) or cyclooxygenase inhibitor mefenamic acid (MA) alone leads to vasoconstriction. We found that l-NNA after MA induced an additional constriction, whereas MA after l-NNA induced a relative dilation.

Impact of serotonin on tumour growth.

Several opposite effects of serotonin (5HT) on tumour growth have been reported. On one hand, 5HT is known as a growth factor for several types of nontumoural cells, and it has been proposed to take part in the autocrine loops of growth factors contributing to cell proliferation in aggressive tumours such as small cell lung carcinoma. Depending on the tumour type either 5HT2 or 5HT1 receptor antagonist have been found to inhibit the 5HT-induced increase in tumour growth.

Role of endothelial factors in the specific response of mouse tumour-feeding arterioles to stimulation of 5-HT1 receptors.

Purpose: To investigate the possible role of endothelial mediators on the increased vasoconstriction to 5-HT1 receptor stimulation by the host-modified arterioles feeding a Meth-A tumour implanted in the flank of female Balb/c mice.

Materials And Methods: Using intravital microscopy, the response to the topical administration of the general 5-HT1 agonist 5-carboxamidotryptamine maleate (5-CT; 10(-6) M to 10(-4) M) by the tumour-feeding arterioles with the responses of tumour-independent arterioles and those of control arterioles from mice without tumour after antagonization or inhibition of the synthesis of endothelial mediators was compared.

Results: The dramatically higher vasoconstriction to 5-CT observed in tumour-feeding arterioles than in tumour-independent or control arterioles still persisted when either nitric oxide synthase, cyclooxygenase, lipoxygenase, or phospholipase A2 were inhibited or when thromboxane A2 or endothelin were antagonized.