High glucose environment inhibits cranial neural crest survival by activating excessive autophagy in the chick embryo

High glucose levels induced by maternal diabetes could lead to defects in neural crest development during embryogenesis, but the cellular mechanism is still not understood. In this study, we observed a defect in chick cranial skeleton, especially parietal bone development in the presence of high glucose levels, which is derived from cranial neural crest cells (CNCC). In early chick embryo, we found that inducing high glucose levels could inhibit the development of CNCC, however, cell proliferation was not significantly involved. Nevertheless, apoptotic CNCC increased in the presence of high levels of glucose. In addition, the expression of apoptosis and autophagy relevant genes were elevated by high glucose treatment. Next, the application of beads soaked in either an autophagy stimulator (Tunicamycin) or inhibitor (Hydroxychloroquine) functionally proved that autophagy was involved in regulating the production of CNCC in the presence of high glucose levels. Our observations suggest that the ERK pathway, rather than the mTOR pathway, most likely participates in mediating the autophagy induced by high glucose. Taken together, our observations indicated that exposure to high levels of glucose could inhibit the survival of CNCC by affecting cell apoptosis, which might result from the dysregulation of the autophagic process

Palliative treatment of upper gastrointestinal obstruction using self-expansible metal stents.

Abstract. – Gastric outlet obstruction is either a late event in the natural history of bilio-pancreatic tumors or the result of recurrent gastric or pancreatic tumors. Self-expansible metal stents, inserted under endoscopic and fluoroscopic control, can be used for palliative treatment. The present study was aimed at evaluating both the feasibility and the results of stenting in patients with malignant gastric outlet obstruction; in addition, some technical suggestions are presented. A total of 33 patients, who had a metal stent positioned, were retrospectively evaluated; 20 of them were women and 13 were men, aged from 45 to 94 years, with a mean age of 75 years. Twentyseven patients had a pancreatic adenocarcinoma, 4 had a stricture of a gastrojejunal anastomosis due to recurrent pancreatic tumor, 2 had a stricture of a gastrojejunal anastomosis secondary to gastric cancer surgery. No postoperatory complications were observed. Improvement in the quality of life was obtained in all patients. Following the stenting procedure, the median duration of hospitalization was 8 days (range: 6-20 days), and the mean survival rate was 12 weeks (range: 2-66 weeks). Endoscopic stenting for the palliation of malignant gastric outlet obstruction is feasible and is well tolerated by most patients. In some cases a period of enteral nutrition had to be necessarily carried out; nonetheless, the insertion of the stent improved the quality of life. Key Words: Gastrointestinal obstruction, Bilio-pancreatic tumor

Palliative Treatment of Upper Gastrointestinal Obstruction Using Self-Expansible Metal Stents

Gastric outlet obstruction is either a late event in the natural history of bilio-pancreatic tumors or the result of recurrent gastric or pancreatic tumors. Self-expansible metal stents, inserted under endoscopic and fluoroscopic control, can be used for palliative treatment. The present study was aimed at evaluating both the feasibility and the results of stenting in patients with malignant gastric outlet obstruction; in addition, some technical suggestions are presented. A total of 33 patients, who had a metal stent positioned, were retrospectively evaluated; 20 of them were women and 13 were men, aged from 45 to 94 years, with a mean age of 75 years. Twenty-seven patients had a pancreatic adenocarcinoma, 4 had a stricture of a gastrojejunal anastomosis due to recurrent pancreatic tumor, 2 had a stricture of a gastrojejunal anastomosis secondary to gastric cancer surgery. No postoperatory complications were observed. Improvement in the quality of life was obtained in all patients. Following the stenting procedure, the median duration of hospitalization was 8 days (range: 6-20 days), and the mean survival rate was 12 weeks (range: 2-66 weeks). Endoscopic stenting for the palliation of malignant gastric outlet obstruction is feasible and is well tolerated by most patients. In some cases a period of enteral nutrition had to be necessarily carried out; nonetheless, the insertion of the stent improved the quality of life

Witnessing eigenstates for quantum simulation of Hamiltonian spectra

The efficient calculation of Hamiltonian spectra, a problem often intractable on classical machines, can find application in many fields, from physics to chemistry. We introduce the concept of an “eigenstate witness” and, through it, provide a new quantum approach that combines variational methods and phase estimation to approximate eigenvalues for both ground and excited states. This protocol is experimentally verified on a programmable silicon quantum photonic chip, a mass-manufacturable platform, which embeds entangled state generation, arbitrary controlled unitary operations, and projective measurements. Both ground and excited states are experimentally found with fidelities >99%, and their eigenvalues are estimated with 32 bits of precision. We also investigate and discuss the scalability of the approach and study its performance through numerical simulations of more complex Hamiltonians. This result shows promising progress toward quantum chemistry on quantum computers