[Robotic versus laparoscopic distal pancreatectomy: a retrospective single-center study].

Objective: To compare the short-term clinical outcomes and cost differences of robotic distal pancreatectomy (RDP) versus laparoscopic distal pancreatectomy (LDP). Methods: The retrospective descriptive study was adopted.The clinical data of 158 patients underwent minimally invasive distal pancreatectomy who were admitted to Fujian Medical University Union Hospital between January 2016 and July 2018 were collected.A 1∶1 matched propensity score (PSM) analysis was performed for the RDP group and the LDP group.Observed indexes included operative time, blood loss, spleen-preserving rate, postoperative hospital stay, morbidity, incidence of pancreatic fistula and hospital costs. T test or rank sum test was used to compare measurement data, χ(2) test or Fisher exact test was used to compare count data. Results: A well-balanced cohort of 41 patients was analyzed.There were 14 males and 27 females in the RDP group, aged (45.2±16.4)years. There were 15 males and 26 females in the LDP group, aged (47.4±14.9) years.The operation time was (209.7±52.9) minutes for the RDP group and (186.5±56.7) minutes for the LDP group (P=0.073). Median blood loss was less in RDP (50(15-175)ml) compared with LDP (100(50-350)ml) (Z=-2.689, P=0.007). Thirty-eight cases of non-malignant diseases were observed in each group and spleen-preserving rate was higher in RDP (76.3%) compared to LDP(44.7%) (χ(2)=7.930, P=0.005).Postoperative hospital stay was similar in the RDP group and the LDP group (RDP: 9.4 days vs. LDP: 10.6 days; P=0.372). The overall morbidity and incidence of pancreatic fistula major complication rates (RDP: 12.2% vs. LDP: 14.6%, P=0.746; RDP: 7.3% vs. LDP: 9.8%, P=1.000) were similar.Total cost of RDP group was higher than that of LDP group ((80 563.7±10 641.8) yuan vs. (57 792.8±8 943.0) yuan, t=4.515, P<0.01). Conclusions: Both RDP and LDP are safe and feasible procedures. RDP is more expensive, but RDP is associated with significantly less blood loss and higher spleen-preserving rate, which is more suitable for the non-malignant diseases of pancreatic body and tail with an expectation of splenic preservation.

[Choices of methods in dividing the neck of pancreas in laparoscopic pancreaticoduodenectomy].

Objective: To discuss the methods, skills and experiences of dividing the neck of pancreas in laparoscopic pancreaticoduodenectomy(LPD). Methods: The clinical data of 58 patients with periampullary tumors who received LPD at the Union Hospital of Fujian Medical University from December 2014 to January 2017 were retrospectively analyzed.There were 26 males and 32 females, ranged from 18 to 65 years, with a mean age of (46±12)years. Results: All of the 58 patients underwent operation smoothly.Three cases underwent open anastomosis via an auxiliary incision after the total resection of specimen laparoscopically, due to the early learning curve of LPD.Two cases transformed into open operation as a result of tumor vascular invasion to portal vein(PV) or superior mesenteric vein(SMV). Fifty-three cases underwent laparoscopic or laparoscopic combined with robotic pancreaticoduodenectomy completely.Forty-two cases ligated gastroduodenal artery(GDA), fully penetrated the interspace between rear of pancreatic neck and SMV, suspended the pancreas and then divided the neck of pancreas from inferior to superior. Thirteen cases fully dissected the interspace between rear of pancreatic neck and SMV, divided the neck of pancreas from inferior to superior and then ligated GDA.Three cases ligated GDA, dissected PV and SMV at the superior and inferior margin of the neck of pancreas separately, and then divided pancreas from anterior to posterior.Mean time of dividing pancreas was (34.9±9.7)minutes, mean volume of blood loss while dividing pancreas was (30.1±8.2)ml.The main postoperative complications included pancreatic fistula(7 cases, Biochemical leak 2 cases, B grade 3 cases, C grade 2 cases), biliary fistula(3 cases), gastric fistula(1 case), delayed gastric emptying(1 case, C grade), abdominal infection(5 cases), hepatic failure (1 case), intra-abdominal hemorrhage(2 cases), reoperation(2 cases). One case died at the perioperative period while others recovered.The mean duration of postoperative stay was (14.2±5.1)days. Conclusions: Dividing the neck of pancreas is one of the most important steps in LPD, which deserved sufficient attention.At the meantime, a suitable method of dividing the neck of pancreas should be chosen according to intraoperative exploration and preoperative imageological examinations.

Cerebrospinal fluid-contacting nucleus mediates nociception via release of fractalkine.

Increasing evidence suggests that the cerebrospinal fluid-contacting nucleus (CSF-contacting nucleus) mediates the transduction and regulation of pain signals. However, the precise molecular mechanisms remain unclear. Studies show that release of fractalkine (FKN) from neurons plays a critical role in nerve injury-related pain. We tested the hypothesis that release of FKN from the CSF-contacting nucleus regulates neuropathic pain, in a chronic constriction injury rat model. The results show that FKN is expressed by neurons, via expression of its only receptor CX3CR1 in the microglia. The levels of soluble FKN (sFKN) were markedly upregulated along with the increase in FKN mRNA level in rats subjected to chronic constriction injury. In addition, injection of FKN-neutralizing antibody into the lateral ventricle alleviated neuropathic pain-related behavior followed by reduction in microglial activation in the CSF-contacting nucleus. The results indicate that inhibition of FKN release by the CSF-contacting nucleus may ameliorate neuropathic pain clinically.

[DNT cell inhibits the growth of pancreatic carcinoma via NKG2D and MICA pathway in vivo].

Objective: To investigate the effects of natural killer group 2 member D (NKG2D) and its ligands major histocompatibility complex class Ⅰ chain-related molecules A(MICA) on DNT cell killing pancreatic carcinoma. Methods: Antibodies adsorption was used to separate DNT cell from human peripheral blood. Human pancreatic tumor models were established via implanting BXPC-3 cells into nude mice, and then mice were randomly divided mice into 3 groups, blank group, gemcitabine group and DNT group. Mice weights and mice tumor volumes were measured every 5 days. After 40 days mice were euthanized at cervical dislocation method. Tumor weights were measured. Relative tumor volume and tumor inhibition rate were calculated. Western blot and qPCR were used to detect the expressions of NKG2D and MICA in the transplanted tumors of the three groups. Results: The blank group tumor volume and weight of blank group were significantly larger than those of gemcitabine group and DNT group (858.7±35.7 mg, 251.1±19.7 mg, 278.5±17.3 mg, P<0.001), but there were no significantly difference between DNT group and gemcitabine group. The tumor inhibition rate of gemcitabine and DNT cell were 40.4% and 35.5%. Western blot and qPCR showed that MICA mRNA and protein levels in blank group were significantly higher than those in DNT group (P=0.001, P=0.003). NKG2D mRNA and protein levels in blank group were significantly lower than those in DNT cells group (P<0.001, P=0.001). Conclusion: DNT cell can significantly inhibit the growth of pancreatic carcinoma in vivo, and the mechanism may be involved in abnormal expressions of MICA and NKG2D.

Effects of alloying element and temperature on the stacking fault energies of dilute Ni-base superalloys.

A systematic study of stacking fault energy (γ(SF)) resulting from induced alias shear deformation has been performed by means of first-principles calculations for dilute Ni-base superalloys (Ni(23)X and Ni(71)X) for various alloying elements (X) as a function of temperature. Twenty-six alloying elements are considered, i.e., Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, and Zr. The temperature dependence of γ(SF) is computed using the proposed quasistatic approach based on a predicted γ(SF)-volume-temperature relationship. Besides γ(SF), equilibrium volume and the normalized stacking fault energy (Γ(SF) = γ(SF)/Gb, with G the shear modulus and b the Burgers vector) are also studied as a function of temperature for the 26 alloying elements. The following conclusions are obtained: all alloying elements X studied herein decrease the γ(SF) of fcc Ni, approximately the further the alloying element X is from Ni on the periodic table, the larger the decrease of γ(SF) for the dilute Ni-X alloy, and roughly the γ(SF) of Ni-X decreases with increasing equilibrium volume. In addition, the values of γ(SF) for all Ni-X systems decrease with increasing temperature (except for Ni-Cr at higher Cr content), and the largest decrease is observed for pure Ni. Similar to the case of the shear modulus, the variation of γ(SF) for Ni-X systems due to various alloying elements is traceable from the distribution of (magnetization) charge density: the spherical distribution of charge density around a Ni atom, especially a smaller sphere, results in a lower value of γ(SF) due to the facility of redistribution of charges. Computed stacking fault energies and the related properties are in favorable accord with available experimental and theoretical data.

First-principles calculations of interfacial and segregation energies in α-Cr2O3.

The interfacial energies of three twin boundaries with low-index boundary planes: prismatic (101⁻0), basal O-terminated (0001), and basal Cr-terminated (0001), and the segregation energies of five doping elements (Ce, Hf, La, Y and Zr) have been calculated as a function of temperature. The static energies at 0 K were obtained through first-principles calculations and the energies at finite temperatures were derived based on the Debye model. The calculation results show that both the interfacial and segregation energies decrease as temperature increases and the segregation energies are found to be proportional to the ionic size mismatch and the interfacial energy. Our combined approaches suggest an efficient and less computationally intensive way to derive grain boundary energetics at finite temperatures.