Search results for " stem"
showing 10 items of 2170 documents
Persistent endotheliopathy in the pathogenesis of long COVID syndrome
2021
Background Persistent symptoms including breathlessness, fatigue, and decreased exercise tolerance have been reported in patients after acute SARS-CoV-2 infection. The biological mechanisms underlying this “long COVID” syndrome remain unknown. However, autopsy studies have highlighted the key roles played by pulmonary endotheliopathy and microvascular immunothrombosis in acute COVID-19. Objectives To assess whether endothelial cell activation may be sustained in convalescent COVID-19 patients and contribute to long COVID pathogenesis. Patients and Methods Fifty patients were reviewed at a median of 68 days following SARS-CoV-2 infection. In addition to clinical workup, acute phase markers, …
Embryonic and foetal Islet-1 positive cells in human hearts are also positive to c-Kit.
2011
During embryogenesis, the mammalian heart develops from a primitive heart tube originating from two bilateral primary heart fields located in the lateral plate mesoderm. Cells belongings to the pre-cardiac mesoderm will differentiate into early cardiac progenitors, which express early transcription factors which are also common to the Isl-1 positive cardiac progenitor cells isolated from the developing pharyngeal mesoderm and the foetal and post-natal mice hearts. A second population of cardiac progenitor cells positive to c-Kit has been abundantly isolated from adult hearts. Until now, these two populations have been considered two different sets of progenitor cells present in the heart in…
An O2-sensitive glomus cell-stem cell synapse induces carotid body growth in chronic hypoxia.
2013
Summary Neural stem cells (NSCs) exist in germinal centers of the adult brain and in the carotid body (CB), an oxygen-sensing organ that grows under chronic hypoxemia. How stem cell lineage differentiation into mature glomus cells is coupled with changes in physiological demand is poorly understood. Here, we show that hypoxia does not affect CB NSC proliferation directly. Rather, mature glomus cells expressing endothelin-1, the O 2 -sensing elements in the CB that secrete neurotransmitters in response to hypoxia, establish abundant synaptic-like contacts with stem cells, which express endothelin receptors, and instruct their growth. Inhibition of glomus cell transmitter release or their sel…
Hypoxic Ventilatory Reactivity in Experimental Diabetes
2015
Diabetes, apart from generalized neuropathy and microangiopathy, involves tissue hypoxia, which may drive chronic proinflammatory state. However, studies on the ventilatory control in diabetes are sparse and conflicting. In this study we examined the function and morphology of diabetic carotid bodies (CBs). Diabetes was evoked in Wistar rats with streptozotocin (70 mg/kg, i.p.). The acute hypoxic ventilatory responses (HVR) to 12 and 8 % O(2) were investigated in conscious untreated rats after 2 and 4 weeks in a plethysmographic chamber. CBs were dissected and subjected to morphologic investigations: (1) electron transmission microscopy for ultrastructure and (2) laser scanning confocal mic…
Assessment of Mobilization Cost for Multiple Myeloma Using 2 Different Mobilization Strategies: High-Dose Cyclophosphamide Versus Plerixafor. on Beha…
2016
Abstract Background. Peripheral blood stem cell (PBSC) collection prior to high dose chemotherapy for autologous transplantation (ASCT) is a standard of care, and an attractive alternative to the use of bone marrow cells, for transplantation in Multiple Myeloma (MM). The optimal methodology for mobilizing PBSC has yet to be defined, both G-CSF and GM-CSF can be used; although, the stimulatory effect may be more pronounced when given after high dose cyclophosphamide (usually administered at a dose of 1.5 to 6g/m2 IV for one to two days) and use of Plerixafor, a CXCR4 antagonist (Mozobil®). The latter 2 options are preferred, overall, in France. Indeed, it was shown that the most recent combi…
The effect of timing on community acquired respiratory virus infection mortality during the first year after allogeneic hematopoietic stem cell trans…
2019
The effect of timing of community acquired respiratory virus (CARV) infection after allogeneic hematopoietic stem cell transplant (allo-HCT) is an as yet unsettled issue. We evaluate this issue by including all consecutive allo-HCT recipients with molecularly-documented CARV infection during the first year after transplant. The study cohort was drawn from a prospective longitudinal survey of CARV in allo-HCT recipient having respiratory symptoms conducted from December 2013 to December 2018 at two Spanish transplant centers. Respiratory viruses in upper and/or lower respiratory specimens were tested using multiplex PCR panel assays. The study cohort comprised 233 allo-HCT recipients with 37…
Vertigo and multiple sclerosis: aspects of differential diagnosis.
2002
Equilibrium disorders caused by involvement of brainstem and cerebellar structures are common in patients with multiple sclerosis (MS), but peripheral conditions such as benign paroxysmal positional vertigo (BPPV) can be sometimes confused with those of a central origin. Therefore, an accurate otoneurologic investigation paying attention to differential diagnosis aspects should be performed in these subjects. Among available diagnostic tools, electro-oculography, posturography and vestibular evoked myogenic potentials (VEMPs) are especially suited to assess vestibulo-oculomotor and vestibulospinal systems. This paper briefly describes the most recent otoneurologic diagnostic strategies for …
Engraftment kinetics of human CD34+ cells from cord blood and mobilized peripheral blood co-transplanted into NOD/SCID mice
2004
We have reported short periods of post transplant neutropenia in human patients co-transplanted with cord blood (CB) and low numbers of haploidentical mobilized peripheral blood (MPB) CD34+ cells. To investigate the effect that the proportion of MPB to CB cells may have on engraftment kinetics, we have co-transplanted fixed numbers of human CB CD34+ cells mixed with different numbers of MPB CD34+ cells into NOD/SCID mice. We periodically quantified the proportion of human cells and the relative contribution of MPB and CB cells to the human engraftment on marrow aspirates. At the lowest MPB/CB ratios (5 : 1, 10 : 1), the contribution of CB cells predominated at all time points analyzed, and …
Nitric oxide in the pathogenesis of vascular disease
2000
Nitric oxide (NO) is synthesized by at least three distinct isoforms of NO synthase (NOS). Their substrate and cofactor requirements are very similar. All three isoforms have some implications, physiological or pathophysiological, in the cardiovascular system. The endothelial NOS III is physiologically important for vascular homeostasis, keeping the vasculature dilated, protecting the intima from platelet aggregates and leukocyte adhesion, and preventing smooth muscle proliferation. Central and peripheral neuronal NOS I may also contribute to blood pressure regulation. Vascular disease associated with hypercholesterolaemia, diabetes, and hypertension is characterized by endothelial dysfunct…
Obstetric and offspring risks of women’s morbid conditions linked to prior anticancer treatments
2016
Background Literature shows the effects of type of cancer and/or anticancer treatment on live birth percentages and/or pregnancy and neonatal complications in female cancer survivors. However, studies analyzing the obstetric and offspring risks of the morbid conditions associated with previous anti-cancer treatments are missing. The present review aims to uncover these risks. Methods A literature search based on publications up to March 2016 identified by PubMed and references cited in relevant articles. Results The morbid conditions associated with prior anticancer treatments including chemotherapy, radiotherapy, surgery, and/or hematopoietic stem-cell transplant may induce not only obstet…