Search results for " Repair"
showing 10 items of 721 documents
Wharton’s Jelly Mesenchymal Stem Cells for the Treatment of Type 1 Diabetes
2014
Type 1 diabetes is an autoimmune disease caused by the destruction of endocrine pancreas β cells by T lymphocytes, for which genetic and environmental risk factors have been proposed. Patients require daily infusions of recombinant insulin to overcome the reduced production by their own cells, but there is an increasing demand for a permanent and efficient supplementation which could better modulate the need for the hormone during the normal activities. For this reason, transplant-based therapeutic models have been proposed such as whole organ transplantation and Langerhans islets transplantation. These techniques are limited by many factors such as the lack of donors, the risks linked to t…
In vivo reprogramming for tissue repair.
2015
Berninger and colleagues define milestones for in vivo reprogramming and discuss recent developments in reprogramming into pancreatic b-cells and neurons. Vital organs such as the pancreas and the brain lack the capacity for effective regeneration. To overcome this limitation, an emerging strategy consists of converting resident tissue-specific cells into the cell types that are lost due to disease by a process called in vivo lineage reprogramming. Here we discuss recent breakthroughs in regenerating pancreatic β-cells and neurons from various cell types, and highlight fundamental challenges that need to be overcome for the translation of in vivo lineage reprogramming into therapy.
The expression of CD68 in human umbilical cord mesenchymal stem cells: new evidences of presence in non-myeloid cell types.
2009
Since their first identification in bone marrow [2],MSC have attracted much attention for thei r potential todifferentiate towards several mature tissues. The efforts ofthe researchers aimed in finding new tissues, whichshould provide adequate cell numbers for regenerativemedicine applications (and between them, extraembryonicsources as umbilical cord and amniotic membrane, arebeing viewed with extreme interest).
Umbilical cord versus bone marrow-derived mesenchymal stromal cells.
2012
incetheplacentaisapostnatal tissue and discarded asmedical waste, harvesting stem cells from this organrepresents a noninvasive and ethically conductive proce-dure. Perinatal stem cells isolated from amnion, chorion,umbilical cord, and cord blood are increasingly viewedas reliable sources of mesenchymal stromal cells (MSCs)alternative to bone marrow-derived ones (BM-MSCs),which are currently the most commonly used in clinicalapplications [1–5].Perinatal stem cells are a bridge between embryonic stemcells (ESCs) and adult stem cells (such as BM-MSCs). Theyshare many characteristics of both cells [1,6]. Considering thestructural complexity of the term ‘‘placenta,’’ we have fo-cused our attent…
Human Wharton's jelly mesenchymal stem cells maintain the expression of key immunomodulatory molecules when subjected to osteogenic, adipogenic and c…
2013
Rheumatoid arthritis and osteoarthritis are the main diseases that imply an inflammatory process at the joints involving the articular cartilage. Recently, mesenchymal stem cells (MSCs) derived from perinatal tissues were considered good candidates for cellular therapy of musculoskeletal and orthopaedic diseases, since they can differentiate into multiple cell types and are an easily accessible cellular source. Therefore, several protocols exist on the differentiation of mesenchymal stem cells of different origins into osteoblasts and chondrocytes. Another key feature of MSCs is their capacity to modulate the immune system responses in vitro and in vivo. This may have critical outcomes in d…
Experimental results of RC columns strengthnened with Fiber Reinforced Cementitious Mortars
2012
The structural behaviour of reinforced concrete columns strengthened with a system made up of fibre nets embedded in an inorganic stabilized cementitious matrix was investigated. Specimens with circular and square cross-section were cast and subjected to monotonic uniaxial compression to investigate the efficiency of a Polypara-phenylene-benzo-bisthiazole (PBO) Fibre Reinforced Cementitious Mortars (FRCM) system in increasing both carrying capacity and ductility. The experimental results show that confinement with PBO fibre produced a noticeable increment in strength and ductility, though the low mechanical ratios of fibre considered were not always able to ensure hardening behaviour up to …
p53 is involved in regulation of the DNA repair gene O6-methylguanine-DNA methyltransferase (MGMT) by DNA damaging agents
1998
The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) is inducible by genotoxic stress. MGMT induction results from transcriptional activation of the MGMT gene which is a specific response to DNA damage. A possible factor involved in triggering MGMT induction might be p53, because both p53 and MGMT are activated by DNA breaks. To study the effect of p53 on induction of the MGMT gene, we compared the presence of functional wild-type (wt) and mutant p53 with MGMT expression level in various mouse fibroblasts and rat hepatoma cell lines upon genotoxic treatment. Cells which responded to ionizing radiation (IR) by MGMT induction displayed functional p53, whereas in cells not expr…
New emerging potentials for human Wharton's jelly mesenchymal stem cells: immunological features and hepatocyte-like differentiative capacity.
2010
In recent years, human mesenchymal stem cells (MSC) have been extensively studied. Their key characteristics of long-term self-renewal and a capacity to differentiate into diverse mature tissues favour their use in regenerative medicine applications. Stem cells can be found in embryonic and extra-embryonic tissues as well as in adult organs. Several reports indicate that cells of Wharton's jelly (WJ), the main component of umbilical cord extracellular matrix, are multipotent stem cells, expressing markers of bone marrow mesenchymal stem cells (BM-MSC), and giving rise to different cellular types of both connective and nervous tissues. Wharton's jelly mesenchymal stem cells (WJ-MSC) express …
Micronucleus frequencies and clonogenic cell survival in TK6 cells exposed to changing dose rates under controlled temperature conditions.
2014
In most exposure scenarios the dose rate of exposure is not constant. Despite this, very little information exists on the possible biological effects of exposing cells to radiation under the conditions of a changing dose rate. The current study highlights interesting effects following exposure under these conditions.We constructed a new exposure facility that allows exposing cells inside an incubator and used it to irradiate human lymphoblastoid TK6 cells both after a moderate (0.48 Gy) and a high (1.1 Gy) dose, where the change in dose rate was, respectively, ≈ 17-fold (2.2-37 mGy/min) and ≈ 39-fold (2.7-106 mGy/min). Clonogenic survival and micronuclei (MN) induction were the chosen endpo…
A Strange Case of Left Bowel Ischemia after Right Hernioplasty
2010
We report the first observed case of a young man who suffered of large and unsuspected left bowel ischemia following an elective right open hernioplasty. A 54-year-old man had a 2-year history of right inguinal reducible mass and was admitted to hospital for an elective day case open inguinal hernioplasty for a direct right inguinal hernia. Apart from mild hypertension controlled with ACE inhibitor, he was medically fit and well. The patient was submitted to open tension-free mesh repair with polypropylene preshaped mesh with local infiltration anesthesia and additive sedation with midazolam. The local anesthesia and surgery were uneventful and he was discharged home on the same day as per …