Aromatic l-amino acid decarboxylase (AADC) deficiency is a rare autosomal recessive disorder that results in a lack of the monoamine neurotransmitters dopamine, serotonin, norepinephrine, and epinephrine. Patients present with a wide spectrum of symptoms, including motor and autonomic dysfunction, hypotonia, and developmental delay, often before the age of one. Until recently, treatment options were limited to symptom control, but the recent approval of the first gene therapy for AADC deficiency in Europe and the UK has provided an alternative to treating symptoms for this disease.
View Article and Find Full Text PDF(1) Background: Adequate organ perfusion during cardiopulmonary bypass (CPB) requires accurate estimation and adjustment of flow rates which conventional methods may not always achieve. Perioperative monitoring of cerebral oxygen saturation (ScO) may detect changes in oxygen transport. This study aims to compare estimated and measured perfusion flow rates and assess the capacity of ScO to detect subtle changes in oxygen transport during CPB.
View Article and Find Full Text PDFTherapeutic angiogenesis represents a promising avenue to revascularize the ischemic heart. Its limited success is partly due to our poor understanding of the cardiac stroma, specifically mural cells, and their response to ischemic injury. Here, we combine single-cell and positional transcriptomics to assess the behavior of mural cells within the healing heart.
View Article and Find Full Text PDFBackground: Double sequential external defibrillation (DSED) has demonstrated increased survival with good neurological outcome in a recent randomized controlled trial. DSED has not been studied in patients with extracorporeal cardiopulmonary resuscitation (eCPR).
Case: We present the first case of prehospital eCPR with ongoing refractory ventricular fibrillation (VF), terminated by DSED.
Efficient regeneration requires multiple cell types acting in coordination. To better understand the intercellular networks involved and how they change when regeneration fails, we profile the transcriptome of hematopoietic, stromal, myogenic, and endothelial cells over 14 days following acute muscle damage. We generate a time-resolved computational model of interactions and identify VEGFA-driven endothelial engagement as a key differentiating feature in models of successful and failed regeneration.
View Article and Find Full Text PDFHere, we ask why the nail base is essential for mammalian digit tip regeneration, focusing on the inductive nail mesenchyme. We identify a transcriptional signature for these cells that includes Lmx1b and show that the Lmx1b-expressing nail mesenchyme is essential for blastema formation. We use a combination of Lmx1bCreERT2-based lineage-tracing and single-cell transcriptional analyses to show that the nail mesenchyme contributes cells for two pro-regenerative mechanisms.
View Article and Find Full Text PDFIntroduction: During cardiopulmonary bypass (CPB), supranormal concentrations of oxygen are routinely administered with the intention to prevent cellular hypoxia. However, hyperoxemia may have adverse effects on patient outcome. Oxygen settings are based on the perfusionist's individual work experience rather than profound recommendations and studies analyzing the effect of oxygen levels are in need of methodological improvement.
View Article and Find Full Text PDFIntroduction: Despite being a daily clinical application in cardiac operating theaters, an evidence-based approach on how to optimally initiate the heart-lung machine (HLM) to prevent critical phases of cerebral ischemia is still lacking. We therefore designed a study comparing two different initiation times for starting the cardiopulmonary bypass (CPB).
Methods: We conducted a monocentric, randomized, and prospective study comparing the impact of two initiation times, a rapid initiation of 15 s and a slow initiation of 180 s to reach the full target flow rate of 2.
J Extra Corpor Technol
September 2021
Near-infrared spectroscopy (NIRS) has been widely used in cardiac surgery to monitor cerebral oxygen supply. The initiation and perioperative management of cardiopulmonary bypass (CPB) constitute critical events in modifying the normal physiology of adequate blood and oxygen supply to the brain. First, little is known about how frequent NIRS is really used.
View Article and Find Full Text PDFBackground: Bowel dysfunction after spinal surgery is often underestimated and if not treated in a timely manner can lead to undesirable surgical interventions or fatal complications. The current medical literature primarily focuses on bowel dysfunction as a result of spinal injury.
Objective: The purpose of this review is to explore this topic in evaluating current evidence regarding the causes of acute bowel dysfunction after elective spinal surgery, primarily the thoracolumbar spine.
Acquired heterotopic ossifications (HO) arising as a result of various traumas, including injury or surgical interventions, often result in pain and loss of motion. Though triggers for HO have been identified, the cellular source of these heterotopic lesions as well as the underlying mechanisms that drive the formation of acquired HO remain poorly understood, and treatment options, including preventative treatments, remain limited. Here, we explore the cellular source of HO and a possible underlying mechanism for their spontaneous osteogenic differentiation.
View Article and Find Full Text PDFThe development of cell therapy for repairing damaged or diseased skeletal muscle has been hindered by the inability to significantly expand immature, transplantable myogenic stem cells (MuSCs) in culture. To overcome this limitation, a deeper understanding of the mechanisms regulating the transition between activated, proliferating MuSCs and differentiation-primed, poorly engrafting progenitors is needed. Here, we show that methyltransferase Setd7 facilitates such transition by regulating the nuclear accumulation of β-catenin in proliferating MuSCs.
View Article and Find Full Text PDFIn this work, we investigate a block Jacobi-Davidson (J-D) variant suitable for sparse symmetric eigenproblems where a substantial number of extremal eigenvalues are desired (e.g., ground-state real-space quantum chemistry).
View Article and Find Full Text PDFFibro/Adipogenic Progenitors (FAPs) are a multipotent progenitor population resident in skeletal muscle. During development and regeneration, FAPs provide trophic support to myogenic progenitors that is required for muscle fiber maturation and specification. FAPs also represent a major cellular source of fibrosis in degenerative disease states, highlighting them as a potential cellular target for anti-fibrotic muscle therapies.
View Article and Find Full Text PDFFibro/adipogenic progenitors (FAPs ) are tissue-resident mesenchymal stromal cells (MSCs). Current literature supports a role for these cells in the homeostasis and repair of multiple tissues suggesting that FAPs may have extensive therapeutic potential in the treatment of numerous diseases. In this context, it is crucial to establish efficient and reproducible procedures to purify FAP populations from various tissues.
View Article and Find Full Text PDFAdministration of the nucleoside adenosine has been shown to induce hypothermia in a number of species, an effect mediated predominantly by the adenosine 1 receptor (A1AR) subtype. The present experiments were performed to explore the possibility that the rise of intracellular adenosine levels expected to accompany adenosine administration may contribute to the hypothermic effect of adenosine independent of A1AR activation. Since phosphorylation of adenosine by adenosine kinase (ADK) is causal in the maintenance of low intracellular adenosine, we have examined the effect of ADK inhibition on core body temperature (CBT).
View Article and Find Full Text PDFRecent research has highlighted the importance of bone and muscle interactions during development and regeneration. There still remains, however, a large gap in the current understanding of the cells and mechanisms involved in this interplay. In particular, how muscle-derived cells, specifically mesenchymal stromal cells (MSCs), can impact bone regeneration or lead to pathologic ectopic bone formation is unclear.
View Article and Find Full Text PDFAm J Physiol Renal Physiol
May 2013
Participation of connexin 40 (Cx40) in the regulation of renin secretion and in the tubuloglomerular feedback (TGF) component of renal autoregulation suggests that gap junctional coupling through Cx40 contributes to the function of the juxtaglomerular apparatus. In the present experiments, we determined the effect of targeted Cx40 deletion in C57BL/6 and FVB mice on TGF responsiveness. In C57BL/6 mice, stop-flow pressure (PSF) fell from 40.
View Article and Find Full Text PDFA(1) adenosine receptors (A1AR) are required for the modulation of afferent arteriolar tone by changes in luminal NaCl concentration implying that extracellular adenosine concentrations need to change in synchrony with NaCl. The present experiments were performed in mice with a null mutation in the gene for the major equilibrative nucleoside transporter ENT1 to test whether interference with adenosine disposition by cellular uptake of adenosine may modify TGF characteristics. Responses of stop flow pressure (P(SF)) to maximum flow stimulation were measured in mice with either C57Bl/6 or SWR/J genetic backgrounds.
View Article and Find Full Text PDFAdenosine 1 receptors (A1AR) have been shown in previous experiments to play a major role in the tubuloglomerular feedback (TGF) constrictor response of afferent arterioles (AA) to increased loop of Henle flow. Overexpression studies have pointed to a critical role of vascular A1AR, but it has remained unclear whether selective deletion of A1AR from smooth muscle cells is sufficient to abolish TGF responsiveness. To address this question, we have determined TGF response magnitude in mice in which vascular A1AR deletion was achieved using the loxP recombination approach with cre recombinase being controlled by a smooth muscle actin promoter (SmCre/A1ARff).
View Article and Find Full Text PDFJ Appl Physiol (1985)
February 2012
Plasma volume (PV) is an important determinant of cardiovascular function and organ perfusion, and it is the target of infusion and diuretic therapies in daily clinical practice. Despite its fundamental importance PV is not commonly measured because available methods of tracer dilution are reliant on dye substances that suffer from numerous drawbacks including binding plasma proteins, spectral changes, and clearance kinetics that complicate analysis and interpretation. To address these issues, we have tested the utility of fluorescent nanoparticles comprised of a dye-rich silica core and polyethylene glycol-coated shell.
View Article and Find Full Text PDFBrain Behav Immun
January 2012
Accidental organophosphate poisoning resulting from environmental or occupational exposure, as well as the deliberate use of nerve agents on the battlefield or by terrorists, remain major threats for multi-casualty events, with no effective therapies yet available. Even transient exposure to organophosphorous compounds may lead to brain damage associated with microglial activation and to long-lasting neurological and psychological deficits. Regulation of the microglial response by adaptive immunity was previously shown to reduce the consequences of acute insult to the central nervous system (CNS).
View Article and Find Full Text PDFThe remnant kidney model in C57BL/6 mice does not develop progressive chronic kidney disease (CKD). In this study we modified the model to mimic features of human CKD and to define accelerants of disease progression using three strains of mice. Following the procedure, there was a progressive increase in albuminuria, progressive loss in renal function, severe glomerulosclerosis and interstitial fibrosis, hypertension, cardiac fibrosis, and anemia by 4 weeks in CD-1 mice and by 12 weeks in 129S3 mice.
View Article and Find Full Text PDFSphingosine kinase 1 (SphK1) and SphK2 are ubiquitous enzymes that generate sphingosine-1-phosphate (S1P), a ligand for a family of G protein-coupled receptors (S1PR1-S1PR5) with important functions in the vascular and immune systems. Here we explore the role of these kinases and receptors in recovery from anaphylaxis in mice. We found that Sphk2-/- mice had a rapid recovery from anaphylaxis.
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