Tumor recurrence after pathological complete response in locally advanced gastric cancer after neoadjuvant therapy:Two case reports

BACKGROUND The pathological complete response(ypCR)rate following neoadjuvant chemotherapy for advanced gastric cancer remains low and lacks a universally accepted treatment protocol.Immunotherapy has achieved breakthrough progress.CASE SUMMARY We report two female patients with gastric cancer defined as clinical stage cT4N1-2M0.Detection of mismatch repair protein showed mismatch repair function defect,and perioperative treatment with programmed death protein 1 inhibitor combined with S-1+oxaliplatin achieved ypCR.Surprisingly,the patients underwent clinical observation after surgery but developed different degrees of metastasis at~6 mo after surgery.CONCLUSION PD-1 inhibitor combined with chemotherapy provides a more strategic choice for comprehensive perioperative treatment of gastric cancer.

Effects of additives on zinc electrodeposition from alkaline zincate solution

The effects of additives on the surface and cross-sectional morphologies of zinc deposits on iron substrate from alkalinezincate solution were characterized by scanning electron microscope(SEM).The cathodic reaction mechanisms under variousconcentrations of additives were investigated using cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)techniques.It is found that with increasing the additive A content in the bath solution,the nucleation overpotential(NOP)value isobviously increased and the inhibition effect is strengthened.This may be mainly due to the adsorption of additive A on the cathodicelectrode surface,which can cover the active sites and block the discharge reduction.The results of EIS analysis indicate that therate-determining step of zinc electrodeposition process is changed from mixed control step into electrochemical reduction step in thepresence of additive A.However,any quantity of additive B has little effect on the NOP value and the inhibition effect is not obvious.Furthermore,addition of additive A and additive B at the same time displays the strongest inhibition effect and shows a strongsynergism because of their co-adsorption on the cathodic electrode surface.

Low-temperature phase transitions of sodium aluminate solutions

A series of low-temperature phase transitions of sodium aluminate solutions were studied by differential scanning calorimetry (DSC) and Raman spectroscopy. The results indicate that NaOH concentration is a primary impact factor for the binary eutectic point and ice melting temperature of sodium aluminate solutions with low NaOH concentration. In addition, the phase transition process of sodium aluminate solutions with low NaOH concentration from 123.15 to 283.15 K is divided into four steps: non-crystal to crystal, ternary eutectic reaction, binary eutectic reaction and ice melt. The projection phase diagram of NaOH-Al(OH)3-H2O system at low temperature was plotted, in which the ternary eutectic temperature for sodium aluminate solutions is 183.15 K.

Cathodic process of nickel electrodeposition from ammonia-ammonium chloride solutions

Mechanism of cathodic process on nickel electrodeposition from ammonia-ammonium chloride solutions was studied by Tafel polarization curves,linear sweep voltammetry(LSV),cyclic voltammograms(CV)and chronopotentiometry(CE)technologies.In the electrolyte with 1.0 mol·L^(-1) NiCl_(2)·6H_(2)O,4.0 mol·L^(-1) NH_(3)·H_(2)O and2.5 mol·L^(-1) NH4Cl,nickel ion mainly complexed with ammonia and almost no free nickel ion could be found.It is confirmed that the dominant form of nickel ammonia complex ion in the system is Ni(NH_(3))_(4)^(2+)by measuring the equilibrium potential of the electrode at various concentrations of ammonia.The species of Ni(NH_(3))42+turns into Ni(NH_(3))_(2)^(2+)during pre-chemical reaction step before discharging reduction reaction.Then,Ni(NH_(3))_(2)^(2+)discharges at the cathodic interface to form metal nickel deposit directly.Nucleation process is involved during nickel electrodeposition according to CV results.The reduction reaction of Ni(NH_(3))_(2)^(2+)is irreversible which is controlled by diffusion step.Other processes are also accompanied during the electrodeposition process,except for the diffusioncontrolled process.