Search results for "Culture Techniques"

Improving vascularization of engineered bone through the generation of pro-angiogenic effects in co-culture systems

2014

One of the major problems with bone tissue engineering is the development of a rapid vascularization after implantation to supply the growing osteoblast cells with the nutrients to grow and survive as well as to remove waste products. It has been demonstrated that capillary-like structures produced in vitro will anastomose rapidly after implantation and become functioning blood vessels. For this reason, in recent years many studies have examined a variety of human osteoblast and endothelial cell co-culture systems in order to distribute osteoblasts on all parts of the bone scaffold and at the same time provide conditions for the endothelial cells to migrate to form a network of capillary-li…

Relevance of Oxygen Concentration in Stem Cell Culture for Regenerative Medicine

2019

The key hallmark of stem cells is their ability to self-renew while keeping a differentiation potential. Intrinsic and extrinsic cell factors may contribute to a decline in these stem cell properties, and this is of the most importance when culturing them. One of these factors is oxygen concentration, which has been closely linked to the maintenance of stemness. The widely used environmental 21% O2 concentration represents a hyperoxic non-physiological condition, which can impair stem cell behaviour by many mechanisms. The goal of this review is to understand these mechanisms underlying the oxygen signalling pathways and their negatively-associated consequences. This may provide a rationale…

First description of nonmotileVibrio vulnificusstrains virulent for eels

2007

Nonmotile Vibrio vulnificus strains were isolated as pure cultures from body ulcers and internal organs of wild diseased European eels caught in a Mediterranean freshwater coastal lagoon. All 54 V. vulnificus isolates were nonmotile, indole-, ornithine decarboxilase-, mannitol- and cellobiose-positive, developed the opaque variant in culture, belonged to the O-antigenic serovar A and were highly virulent for eels by both intraperitoneal injection and immersion challenges. The nonmotile phenotype found in our V. vulnificus isolates was stable: nonmotile cells were always recovered from experimentally infected eels; no variation in the immobility of the V. vulnificus cells was observed for re…

Thymidine-, uridine- and choline-kinase in rabbit kidney cells infected with herpesvirus hominis, type I and II.

1972

Data are presented about the activity of the thymidine-, uridine- and choline-kinase after infection with 21 strains ofherpesvirus hominis of serotype I or II in rabbit kidney cells. Type I strains increase the activity of the thymidine-kinase 15–20 fold over the controls, whereas the type II strains demonstrate a moderate activity, the level of the enzyme is increased 2–5 fold. One giant cell forming strain exhibits unusual properties, the TK activity decreases in correlation to the controls. The uridine- and choline-kinases induce the respective enzymes in different manner. The strains tested are divided into 5 groups depending upon the activity of the enzymatic activity. The implications…

Induction capacity and influence of dThdMP on thymidine kinase activity of type 1 and 2 strains of herpes simplex virus

1978

The thymidine kinase inducing ability of 104 strains of herpes simplex virus was studied comparatively. A pronounced relationship was established between induction of the enzyme and the serotype of the strains. As a rule, the strains of serotype 2 are weaker inducer of dThd- and dCyd-kinase activity than serotype 1 strains. A certain parallelism exists between induction of both enzymes, however the activity of the thymidine kinase increases after infection with herpes simplex virus 4--5 times more than that of the dCyd-kinase. Adaptation of the strains to cell cultures only slightly modifies the inducing ability of the herpes simplex virus strains. The thymidine kinase activity induced by H…

Wharton’s Jelly Mesenchymal Stromal Cells Support the Expansion of Cord Blood–derived CD34+Cells Mimicking a Hematopoietic Niche in a Direct Cell–cel…

2018

Wharton’s jelly mesenchymal stromal cells (WJ-MSCs) have been recently exploited as a feeder layer in coculture systems to expand umbilical cord blood–hematopoietic stem/progenitor cells (UCB-HSPCs). Here, we investigated the role of WJ-MSCs in supporting ex vivo UCB-HSPC expansion either when cultured in direct contact (DC) with WJ-MSCs or separated by a transwell system or in the presence of WJ-MSC–conditioned medium. We found, in short-term culture, a greater degree of expansion of UCB-CD34+cells in a DC system (15.7 ± 4.1-fold increase) with respect to the other conditions. Moreover, in DC, we evidenced two different CD34+cell populations (one floating and one adherent to WJ-MSCs) with …

Searching for wheat plants with low toxicity in celiac disease: Between direct toxicity and immunologic activation.

2009

Abstract Background Natural or induced variations in the noxiousness of gluten proteins for celiac disease (CD) patients are currently being investigated for their potential in breeding wheat crops with reduced toxicity. Aims We evaluated the bread wheat line C173 for its effects on the in vitro -grown duodenal mucosa of CD patients. Methods In vitro -grown duodenal mucosa biopsies of 19 CD patients on a gluten-free diet were exposed to peptic/tryptic-digested prolamins from bread wheat line C173 lacking gliadin–glutenin subunits, analyzed for morphology, cytokine and anti-tTG antibody production, and compared with mucosa biopsies exposed to prolamins from wild-type cv. San Pastore. Results…

Neuroprotective properties of xenon and helium in an in vitro model of traumatic brain injury: one small step or one big jump?

2008

Increased frequencies of CD11b+CD33+CD14+HLA-DRlowmyeloid-derived suppressor cells are an early event in melanoma patients

2014

Myeloid-derived suppressor cells (MDSC) are a heterogeneous cell population characterized by immunosuppressive activity. Elevated levels of MDSC in peripheral blood are found in inflammatory diseases as well as in malignant tumors where they are supposed to be major contributors to mechanisms of tumor-associated tolerance. We investigated the frequency and function of MDSC in peripheral blood of melanoma patients and observed an accumulation of CD11b(+) CD33(+) CD14(+) HLA-DR(low) MDSC in all stages of disease (I-IV), including early stage I patients. Disease progression and enhanced tumor burden did not result in a further increase in frequencies or change in phenotype of MDSC. By investig…

In vitro differentiation of murine hematopoietic progenitor cells toward the myeloid lineage occurs in response to Staphylococcus aureus and yeast sp…

2013

We have studied the effect of inactivated microbial stimuli (Candida albicans, Candida glabrata, Saccharomyces boulardii, and Staphylococcus aureus) on the in vitro differentiation of lineage negative (Lin−) hematopoietic progenitor mouse cells. Purified Lin− progenitors were co-cultured for 7 days with the stimuli, and cell differentiation was determined by flow cytometry analysis. All the stimuli assayed caused differentiation toward the myeloid lineage. S. boulardii and particularly C. glabrata were the stimuli that induced in a minor extent differentiation of Lin− cells, as the major population of differentiated cells corresponded to monocytes, whereas C. albicans and S. aureus induced …