Development of a clinical nomogram for prediction of response to neoadjuvant chemotherapy in patients with advanced gastric cancer

BACKGROUND The efficacy of neoadjuvant chemotherapy(NAC)in advanced gastric cancer(GC)is still a controversial issue.AIM To find factors associated with chemosensitivity to NAC treatment and to provide the optimal therapeutic strategies for GC patients receiving NAC.METHODS The clinical information was collected from 230 GC patients who received NAC treatment at the Central South University Xiangya School of Medicine Affiliated Haikou Hospital from January 2016 to December 2020.Least absolute shrinkage and selection operator logistic regression analysis was used to find the possible predictors.A nomogram model was employed to predict the response to NAC.RESULTS In total 230 patients were finally included in this study,including 154 males(67.0%)and 76 females(33.0%).The mean age was(59.37±10.60)years,ranging from 24 years to 80 years.According to the tumor regression grade standard,there were 95 cases in the obvious response group(grade 0 or grade 1)and 135 cases in the poor response group(grade 2 or grade 3).The obvious response rate was 41.3%.Least absolute shrinkage and selection operator analysis showed that four risk factors significantly related to the efficacy of NAC were tumor location(P<0.001),histological differentiation(P=0.001),clinical T stage(P=0.008),and carbohydrate antigen 724(P=0.008).The C-index for the prediction nomogram was 0.806.The calibration curve revealed that the predicted value exhibited good agreement with the actual value.Decision curve analysis showed that the nomogram had a good value in clinical application.CONCLUSION A nomogram combining tumor location,histological differentiation,clinical T stage,and carbohydrate antigen 724 showed satisfactory predictive power to the response of NAC and can be used by gastrointestinal surgeons to determine the optimal treatment strategies for advanced GC patients.

Robotic pancreaticoduodenectomy for pancreatic ductal adenocarcinoma: Analysis of surgical outcomes and long-term prognosis in a high-volume center

Background: Robotic pancreaticoduodenectomy(RPD) has been reported to be safe and feasible for patients with pancreatic ductal adenocarcinoma(PDAC) of the pancreatic head. This study aimed to analyze the surgical outcomes and risk factors for poor long-term prognosis of these patients. Methods: Data from patients who underwent RPD for PDAC of pancreatic head were retrospectively analyzed. Multivariate Cox regression analysis was used to seek the independent prognostic factors for overall survival(OS), and an online nomogram calculator was developed based on the independent prognostic factors. Results: Of the 273 patients who met the inclusion criteria, the median operative time was 280.0 minutes, the estimated blood loss was 100.0 m L, the median OS was 23.6 months, and the median recurrence-free survival(RFS) was 14.4 months. Multivariate analysis showed that preoperative carbohydrate antigen 19-9(CA19-9) [hazard ratio(HR) = 2.607, 95% confidence interval(CI): 1.560-4.354, P < 0.001], lymph node metastasis(HR = 1.429, 95% CI: 1.005-2.034, P = 0.047), tumor moderately(HR = 3.190, 95% CI: 1.813-5.614, P < 0.001) or poorly differentiated(HR = 5.114, 95% CI: 2.839-9.212, P < 0.001), and Clavien-Dindo grade ≥ Ⅲ(HR = 1.657, 95% CI: 1.079-2.546, P = 0.021) were independent prognostic factors for OS. The concordance index(C-index) of the nomogram constructed based on the above four independent prognostic factors was 0.685(95% CI: 0.640-0.729), which was significantly higher than that of the AJCC staging(8th edition): 0.541(95% CI: 0.493-0.589)( P < 0.001). Conclusions: This large-scale study indicated that RPD was feasible for PDAC of pancreatic head. Preoperative CA19-9, lymph node metastasis, tumor poorly differentiated, and Clavien-Dindo grade ≥ Ⅲ were independent prognostic factors for OS. The online nomogram calculator could predict the OS of these patients in a simple and convenient manner.

Derivation and validation of a preoperative prognostic model for resectable pancreatic ductal adenocarcinoma

Background: The prognosis of patients with pancreatic ductal adenocarcinoma(PDAC) remains poor even after radical pancreaticoduodenectomy(PD). The study aimed to develop and validate a novel preoperative prognostic model to accurately predict the long-term survival of patients with PDAC.Methods: Patients with PDAC of pancreatic head from Chinese PLA General Hospital were included. The preoperative PDAC model with contour plots was developed using a non-linear model in the training cohort and then tested in the validation cohort.Results: Of 421 patients who met the inclusion criteria, 280 were in the training cohort and 141 in the validation cohort. Contour plots for preoperative PDAC model were established to visually predict the survival probabilities of these patients, based on preoperative carbohydrate antigen 19-9, preoperative fibrinogen to albumin ratio and pain symptoms. This model stratified patients into low-and high-risk groups with distinctly different long-term survival in the training cohort [median overall survival(OS)32.1 vs. 17.5 months;median recurrence-free survival(RFS) 19.3 vs. 10.0 months, both P < 0.001] and the validation cohort(median OS 28.3 vs. 19.0 months;median RFS 17.5 vs. 11.2 months, both P < 0.001).Time-dependent receiver operating characteristic and decision curve analyses revealed that the model provided higher diagnostic accuracy and superior net benefit compared to other staging systems.Conclusions: This study constructed and validated a novel preoperative prognostic model that can accurately and conveniently predict the long-term survival of patients with resectable PDAC of pancreatic head. Besides, the model can screen high-risk patients with poor prognosis, which may provide references for personal treatment strategies in the future.

Clinical diagnosis and management of pancreatic mucinous cystadenoma and cystadenocarcinoma:Single-center experience with 82 patients

BACKGROUND Mucinous cystic neoplasm(MCN)of the pancreas is characterized by mucinproducing columnar epithelium and dense ovarian-type stroma and at risk for malignant transformation.Early diagnosis and treatment of MCN are particularly important.AIM To investigate the clinical characteristics of and management strategies for pancreatic mucinous cystadenoma(MCA)and mucinous cystadenocarcinoma(MCC).METHODS The clinical and pathological data of 82 patients with pancreatic MCA and MCC who underwent surgical resection at our department between April 2015 and March 2019 were retrospectively analyzed.RESULTS Of the 82 patients included in this study,70 had MCA and 12 had MCC.Tumor size of MCC was larger than that of MCA(P=0.049).Age and serum levels of tumor markers carcinoembryonic antigen(CEA),carbohydrate antigen(CA)19-9,and CA12-5 were significantly higher in MCC than in MCA patients(P=0.005,0.026,and 0.037,respectively).MCA tumor size was positively correlated with serum CA19-9 levels(r=0.389,P=0.001).Compared with MCC,MCA had a higher minimally invasive surgery rate(P=0.014).In the MCA group,the rate of major complications was 5.7%and that of clinically relevant pancreatic fistula was 8.6%;the corresponding rates in the MCC group were 16.7%and 16.7%,respectively.CONCLUSION Tumor size,age,and serum CEA,CA19-9,and CA12-5 levels may contribute to management of patients with MCN.Surgical resection is the primary treatment modality for MCC and MCA.

Low-temperature synthesis of apatite-type La_(9.33)Ge_6O_(26) as electrolytes with high conductivity

In the present study,high-quality apatite-type La9.33Ge6O26 powders are successfully synthesized by a facile moltensalt synthesis method（MSSM） at low temperatures,using Li Cl,Li Cl/Na Cl mixture（mass ratio 1：1） as molten salt,respectively.Experimental results indicate that the optimal mass ratio between reactant and molten salt is 1：2,and Li Cl/Na Cl mixed molten-salt is more beneficial for forming high-quality La9.33Ge6O26 powders than Li Cl individual molten-salt.Comparing with the conventional solid-state reaction method（SSRM）,the synthesis temperature of apatitetype La9.33Ge6O26 powders using the MSSM decreases more than 350℃,which can effectively avoid Ge loss in the preparation process of precursor powders.Furthermore,the powders obtained by the MSSM are homogeneous,nonagglomerated and well crystallized,which are very favorable for gaining dense pellets in the premise of avoiding Ge loss.On the basis of high-quality precursor powders,the dense and pure ceramic pellets of La（9.33）Ge6O（26） are gained at a low temperature of 1100℃ for 2 h,which exhibit higher conductivities（σ850℃（Li Cl）= 2.3 × 10^-2 S·cm^-1,σ850 ℃（Li Cl/Na Cl） = 4.9 × 10^-2 S·cm^-1） and lower activation energies（Ea（Li Cl）= 1.02 e V,Ea（Li Cl/Na Cl）= 0.99 e V） than that synthesized by the SSRM.

In-situ fabrication of ZnO nanoparticles sensors based on gas-sensing electrode for ppb-level H_(2)S detection at room temperature

The zinc oxide(ZnO)nanoparticles(NPs)sensors were prepared in-situ on the gas-sensing electrodes by a one-step simple sol-gel method for the detection of hydrogen sulfide(H_(2)S)gas.The sphere-like ZnO NPs were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),x-ray diffraction(XRD),energy dispersive x-ray analysis(EDX),and their H_(2)S sensing performance were measured at room temperature.Testing results indicate that the ZnO NPs exhibit excellent response to H_(2)S gas at room temperature.The response value of the optimal sample to750 ppb H_(2)S is 73.3%,the detection limit reaches to 30 ppb,and the response value is 7.5%.Furthermore,the effects of the calcining time and thickness of the film on the gas-sensing performance were investigated.Both calcining time and film thickness show a negative correlation with the H_(2)S sensing performance.The corresponding reaction mechanism of H_(2)S detection was also discussed.

On the prevention and treatment of cervical spondylosis^1

Cervical spondylosis is a kind of frequently occurring and refractory disease with high recurrence rate and tends to be younger. It has become a multiple refractory disease at home and abroad, and its mechanism research and clinical diagnosis and treatment are still controversial. This article will discuss the etiology, pathogenesis, mechanism and treatment of cervical spondylosis from ancient Chinese medicine and modern western medicine, and focus on the research progress of modern prevention and treatment of cervical spondylosis, in order to provide reference for modern clinical treatment of cervical spondylosis.

A Continuous State Feedback Controller Design for High-order Nonlinear Systems with Polynomial Growth Nonlinearities

In this paper, we investigate the problem of global stabilization for a general class of high-order and non-smoothly stabilizable nonlinear systems with both lower-order and higher-order growth conditions. The designed continuous state feedback controller is recursively constructed to guarantee the global strong stabilization of the closed-loop system.

Smoothness preserving layout for dynamic labels by hybrid optimization

Stable label movement and smooth label trajectory are critical for effective information understanding.Sudden label changes cannot be avoided by whatever forced directed methods due to the unreliability of resultant force or global optimization methods due to the complex trade-off on the different aspects.To solve this problem,we proposed a hybrid optimization method by taking advantages of the merits of both approaches.We first detect the spatial-temporal intersection regions from whole trajectories of the features,and initialize the layout by optimization in decreasing order by the number of the involved features.The label movements between the spatial-temporal intersection regions are determined by force directed methods.To cope with some features with high speed relative to neighbors,we introduced a force from future,called temporal force,so that the labels of related features can elude ahead of time and retain smooth movements.We also proposed a strategy by optimizing the label layout to predict the trajectories of features so that such global optimization method can be applied to streaming data.

PREPARATION OF MDPE-g-MAH COPOLYMERS AND THEIR EFFECT ON PROPERTIES OF MDPE/CaCO_3 SYSTEMS

MDPE-g-MAH copolymers were prepared with MDPE （medium density polyethylene） and MAH （maleic anhydride） under different irradiation doses of high-energy electron accelerator, and FTIR spectra confirmed their structure. The effect of the different contents of MDPE-g-MAH copolymers on properties of MDPE/CaCO3 system is studied intensively. By adding 4 Phr （parts per hundred of resin） MDPE-g-MAH in MDPE/CaCO3 system under irradiation dose of 0.7 MGy, the tensile strength increases from 16.3 MPa to 19.9 MPa, and elongation at break increases from 437% to 518%. SEM images show the domain size of CaCO3 in MDPE-g-MAH systems becomes small. Definitely, MDPE-g-MAH copolymer could improve the compatibility of MDPE/CaCO3 system effectively.