57 research outputs found
Functional Expression of the Extracellular Calcium Sensing Receptor (CaSR) in Equine Umbilical Cord Matrix Size-Sieved Stem Cells
The present study investigates the effects of high external calcium concentration ([Ca(2+)](o)) and the calcimimetic NPS R-467, a known calcium-sensing receptor (CaSR) agonist, on growth/proliferation of two equine size-sieved umbilical cord matrix mesenchymal stem cell (eUCM-MSC) lines. The involvement of CaSR on observed cell response was analyzed at both the mRNA and protein level.A large (>8 µm in diameter) and a small (<8 µm) cell line were cultured in medium containing: 1) low [Ca(2+)](o) (0.37 mM); 2) high [Ca(2+)](o) (2.87 mM); 3) NPS R-467 (3 µM) in presence of high [Ca(2+)](o) and 4) the CaSR antagonist NPS 2390 (10 µM for 30 min.) followed by incubation in presence of NPS R-467 in medium with high [Ca(2+)](o). Growth/proliferation rates were compared between groups. In large cells, the addition of NPS R-467 significantly increased cell growth whereas increasing [Ca(2+)](o) was not effective in this cell line. In small cells, both higher [Ca(2+)](o) and NPS R-467 increased cell growth. In both cell lines, preincubation with the CaSR antagonist NPS 2390 significantly inhibited the agonistic effect of NPS R-467. In both cell lines, increased [Ca(2+)](o) and/or NPS R-467 reduced doubling time values.Treatment with NPS R-467 down-regulated CaSR mRNA expression in both cell lines. In large cells, NPS R-467 reduced CaSR labeling in the cytosol and increased it at cortical level.In conclusion, calcium and the calcimimetic NPS R-467 reduce CaSR mRNA expression and stimulate cell growth/proliferation in eUCM-MSC. Their use as components of media for eUCM-MSC culture could be beneficial to obtain enough cells for down-stream purposes
Risk factors in the development of stem cell therapy
Stem cell therapy holds the promise to treat degenerative diseases, cancer and repair of damaged tissues for which there are currently no or limited therapeutic options. The potential of stem cell therapies has long been recognised and the creation of induced pluripotent stem cells (iPSC) has boosted the stem cell field leading to increasing development and scientific knowledge. Despite the clinical potential of stem cell based medicinal products there are also potential and unanticipated risks. These risks deserve a thorough discussion within the perspective of current scientific knowledge and experience. Evaluation of potential risks should be a prerequisite step before clinical use of stem cell based medicinal products
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
Emerging issues of the expression profiling technologies for the study of gynecologic cancer
Evaluation of the prognostic parameters of gynecologic cancer has shown
their failure for classification according to the clinical behavior or
the prediction of its outcome. This weakness has important implications
on prognosis and treatment. The increasing understanding of the
complexity of the human genome, coupled with the development of high
throughput analysis techniques and bioinformatics tools, has changed our
concepts on cancer biology, by shifting our targets to a global analysis
of the transcriptome and the proteome, linking genes and their products
into functional pathways. These approaches permit the documentation of
expression patterns of thousands of genes within a cell. With the use of
DNA microarray technology, it is feasible to identify signature patterns
of expression in tumor samples that faithfully correlate with its
biology, providing accurate prognosis for each cancer patient and thus a
rational customized treatment. At this stage, there is a need for
systematic studies for the validation of these novel approaches. In this
review, we provide a basic back-round of the concept of the technology,
highlight several ernerging issues from their applications on
gynecologic cancer, discuss a series of important themes and problems
regarding their interpretation and relevance for the clinicians, and
comment on future areas of research. (C) 2005 Elsevier Inc. All rights
reserved
Spindle shaped human mesenchymal stem/stromal cells from amniotic fluid promote neovascularization
Human amniotic fluid obtained at amniocentesis, when cultured, generates at least two morphologically distinct mesenchymal stem/stromal cell (MSC) subsets. Of these, the spindle shaped amniotic fluid MSCs (SS-AF-MSCs) contain multipotent cells with enhanced adipogenic, osteogenic and chondrogenic capacity. Here, we demonstrate, for the first time, the capacity of these SS-AF-MSCs to support neovascularization by umbilical cord blood (UCB) endothelial colony forming cell (ECFC) derived cells in both in vitro and in vivo models. Interestingly, although the kinetics of vascular tubule formation in vitro were similar when the supporting SS-AF-MSCs were compared with the best vasculogenic supportive batches of bone marrow MSCs (BMSCs) or human dermal fibroblasts (hDFs), SS-AF-MSCs supported vascular tubule formation in vivo more effectively than BMSCs. In NOD/SCID mice, the human vessels inosculated with murine vessels demonstrating their functionality. Proteome profiler array analyses revealed both common and distinct secretion profiles of angiogenic factors by the SS-AF-MSCs as opposed to the hDFs and BMSCs. Thus, SS-AF-MSCs, which are considered to be less mature developmentally than adult BMSCs, and intermediate between adult and embryonic stem cells in their potentiality, have the additional and very interesting potential of supporting increased neovascularisation, further enhancing their promise as vehicles for tissue repair and regeneration
Gestational diabetes exhibits lack of carnitine deficiency despite relatively low carnitine levels and alterations in ketogenesis
Objective: Previous studies have underlined the importance of the
carnitine shuttle system and its dysfunction both in normal pregnancy
and in type 1 and 2 diabetes. The objective of this paper was to
delineate more systematically the role of the carnitine shuttle system
in normal pregnancy and in gestational diabetes.
Methods: A total of 119 women matched for age comprised three groups: 40
normal adult non-pregnant women (NNP), 46 normal pregnant women with
uncomplicated pregnancy (NP) and 33 women with gestational diabetes
(GDM). The latter group was further subdivided into those being managed
either by diet alone ( 25 women, GDM-D) or by insulin ( 8 women, GDM-I).
The following biochemical parameters were assayed: fasting plasma total,
free and acyl-carnitine, FFA and beta-OH-butyrate, together with several
essential anthropometric parameters.
Results: Women with GDM, in contrast to the control groups, displayed
the biochemical features characteristic of insulin resistance: higher
body weight, higher BMI, higher skinfold and higher HbA1c levels. No
differences on any parameters were found between the two GDM subgroups.
Both NP and GDM groups had low levels of total carnitine compared to NNP
control group, but surprisingly, the GDM group did not exhibit any
further decrease of carnitine levels, as would have been expected by the
combination of pregnancy and diabetes. Both groups, despite these low
carnitine levels, had no clinical symptoms of carnitine deficiency.
Furthermore, the GDM group displayed higher levels of FFA and
beta-hydroxybutyrate, which were statistically significant compared to
the other two control groups.
Conclusions: The data corroborate the negative effect of normal
gestation on the carnitine shuttle system, while they document for the
first time that GDM does not further affect the efficiency of the
carnitine system. The mild effect of GDM on carnitine status could be
explained by the concurrent increased gluconeogenesis, a process which
does not affect directly carnitine metabolism
Consistent absence of BRAF mutations in cervical and endometrial cancer despite KRAS mutation status
Background. Mutational activation of KRAS and BRAF proto-oncogenes
contributes to the development of many human cancers. Current research
on gynecological cancer and specifically in cervical and endometrial
cancer is focused on the mechanisms of their mutational activation.
Objectives. In view of the paucity of data on their mutation frequency
and the status of BRAF in these two types of gynecological cancer, we
performed a systematic molecular study in 114 clinically and
histologically well-defined malignant tumors of uterine cervix and
endometrium and correlated the mutation status of KRAS and BRAF with the
age at diagnosis and with tumor grade, stage or histological type.
Methods. Direct sequence analysis of the PCR products of KRAS and BRAF
genes was used to screen for known activating mutations.
Results. In 67 cases of endometrial cancer, six KRAS mutations (8.9%)
were found, four at codon 12 (5.9%) and two at codon 13 (2.9%), while
no mutation was detected at codon 61. Most of the mutations occurred in
surgical stage I and in the endometrioid adenocarcinoma subtype. We also
detected three KRAS point mutations (6.3%) in the 47 cervical cancer
samples, two at codon 12 (4.2%) and one at codon 13 (2.1%), while
there was 110 Mutation at codon 61. On the contrary, no mutation was
identified in BRAF exon 15 for either endometrial or cervical cancer
samples at position V600, which represents the most frequently mutated
site of BRAF in human cancer. There was no association between KRAS
mutations with either histological type, tumor grade or stage.
Interestingly, however, KRAS mutation status in endometrial cancer was
strongly associated with increased age at diagnosis (P < 0.001).
Conclusions. Our data document (a) the absence of BRAF mutations in
cervical and endometrial cancer, despite the mutation status of KRAS,
(b) suggest that KRAS Mutations reflect an early event in endometrial
carcinogenesis and (c) imply that BRAF activation is involving
alternative pathways in these two types of cancer. (C) 2005 Elsevier
Inc. All rights reserved
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