21 research outputs found
Stem cell senescence: effects of REAC technology on telomerase-independent and telomerase-dependent pathways
Decline in the gene expression of senescence repressor Bmi1, and telomerase, together with telomere
shortening, underlay senescence of stem cells cultured for multiple passages. Here, we investigated whether
the impairment of senescence preventing mechanisms can be efficiently counteracted by exposure of human
adipose-derived stem cells to radio electric asymmetrically conveyed fields by an innovative technology,
named Radio Electric Asymmetric Conveyer (REAC). Due to REAC exposure, the number of stem cells
positively stained for senescence associated ß-galactosidase was significantly reduced along multiple
culturing passages. After a 90-day culture, REAC-treated cells exhibited significantly higher transcription of
Bmi1 and enhanced expression of other stem cell pluripotency genes and related proteins, compared to
unexposed cells. Transcription of the catalytic telomerase subunit (TERT) was also increased in
REAC-treated cells at all passages. Moreover, while telomere shortening occurred at early passages in both
REAC-treated and untreated cells, a significant rescue of telomere length could be observed at late passages
only in REAC-exposed cells. Thus, REAC-asymmetrically conveyed radio electric fields acted on a gene and
protein expression program of both telomerase-independent and telomerase-dependent patterning to
optimize stem cell ability to cope with senescence progression
Mechanical Stimulation of Fibroblasts by Extracorporeal Shock Waves: Modulation of Cell Activation and Proliferation Through a Transient Proinflammatory Milieu
Extracorporeal shock waves (ESWTs) are \u201cmechanical\u201d waves, widely used in regenerative medicine, including soft tissue wound repair. Although already being used in the clinical practice, the mechanism of action underlying their biological activities is still not fully understood. In the present paper we tried to elucidate whether a proinflammatory effect may contribute to the regenerative potential of shock waves treatment. For this purpose, we exposed human foreskin fibroblasts (HFF1 cells) to an ESWT treatment (100 pulses using energy flux densities of 0.19 mJ/mm2 at 3 Hz), followed by cell analyses after 5 min, up to 48 h. We then evaluated cell proliferation, reactive oxygen species generation, ATP release, and cytokine production. Cells cultured in the presence of lipopolysaccharide (LPS), to induce inflammation, were used as a positive control, indicating that LPS-mediated induction of a proinflammatory pattern in HFF1 increased their proliferation. Here, we provide evidence that ESWTs affected fibroblast proliferation through the overexpression of selected cytokines involved in the establishment of a proinflammatory program, superimposable to what was observed in LPS-treated cells. The possibility that inflammatory circuits can be modulated by ESWT mechanotransduction may disclose novel hypothesis on their biological underpinning and expand the fields of their biomedical application
Clinical value of CA 19-9 (carbohydrate antigen) in gastrointestinal adenocarcinoma.
CA 19-9 and CEA serum levels were determined before and 7 days after surgery in 140 patients with gastrointestinal adenocarcinoma, and in 70 patients with gastrointestinal non neoplastic diseases. CA 19-9 test was shown to be positive in 37.9% of colorectal cancer, in 32.6% of gastric cancer and in 77.8% of pancreatic cancer. CA 19-9 test was also shown to be more sensitive for colonic cancer with respect to rectal cancer (40.9% vs. 23.5%). CA 19-9 test is more sensitive and specific than CEA. In particular, the reported results suggest the clinical value of CA 19-9 test in the diagnosis of pancreatic adenocarcinoma and as a suitable parameter in the follow-up of gastrointestinal cancer