Advances in cell nuclear mechanobiology and its regulation mechanisms / 生物医学工程学杂志

As an important intracellular genetic and regulatory center, the nucleus is not only a terminal effector of intracellular biochemical signals, but also has a significant impact on cell function and phenotype through direct or indirect regulation of nuclear mechanistic cues after the cell senses and responds to mechanical stimuli. The nucleus relies on chromatin-nuclear membrane-cytoskeleton infrastructure to couple signal transduction, and responds to these mechanical stimuli in the intracellular and extracellular physical microenvironments. Changes in the morphological structure of the nucleus are the most intuitive manifestation of this mechanical response cascades and are the basis for the direct response of the nucleus to mechanical stimuli. Based on such relationships of the nucleus with cell behavior and phenotype, abnormal nuclear morphological changes are widely used in clinical practice as disease diagnostic tools. This review article highlights the latest advances in how nuclear morphology responds and adapts to mechanical stimuli. Additionally, this article will shed light on the factors that mechanically regulate nuclear morphology as well as the tumor physio-pathological processes involved in nuclear morphology and the underlying mechanobiological mechanisms. It provides new insights into the mechanisms that nuclear mechanics regulates disease development and its use as a potential target for diagnosis and treatment.

Research progress of transplantation acquired food allergy / 中华消化外科杂志

Transplantation acquired food allergy (TAFA) is a rare complication of solid organ transplantation. The pathogenesis of TAFA has not been fully elucidated. There are two possible mechanisms for its occurrence: food allergy mediated by IgE delivery of the donor and food allergy caused by food intolerance after transplantation. At present, there is still insufficient understanding of this complication among transplant physicians. Through systematic review of relevant literature, the authors summarized the research progress of TAFA, which mainly included the pathogenesis, clinical characteristics, treatment and prognosis of TAFA. In order to provide reference for the diagnosis and treatment of TAFA.

Association between expression of Cullin 4B and prognosis of patients after liver transplantation / 中华消化外科杂志

Objective To investigate the effect of expression of Cullin 4B (CUL4B) on the prognosis of patients after liver transplantation for hepatocellular carcinoma (HCC).Methods The retrospective case-control study was conducted.The clinicopathological data of 79 patients who underwent liver transplantation for HCC in the First Affiliated Hospital of Sun Yat-sen University between January 1,2014 and June 30,2015 were collected.The specimens of HCC tissues were collected and embedded in paraffin,and then were detected by immunohistochemistry staining.Observation indicators:(1) expression of CUL4B in HCC tissues;(2) follow-up and survival;(3) prognostic factors analysis after liver transplantation;(4) association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantation.Follow-up using outpatient examination and telephone interview was performed to detect tumor recurrence or metastasis and survival up to June 2018.Measurement data with normal distribution were represented as (x)±s.The comparison between groups of count data was done using the chi-square test.The survival curve drawn using the Kaplan-Meier method,and the survival analysis was done by Log-rank test.The univariate and multivariate analysis were respectively done using the COX regression model.The association analysis was done using the Pearson test.Results (1) Expression of CUL4B in HCC tissues:immunohistochemistry staining showed that CUL4B was mainly expressed in the cytoplasm,with a powerful brownish-yellow staining.The high expression and low expression of CUL4B in HCC tissues were detected in 64 and 15 patients,respectively.(2) Follow-up and survival:79 patients were followed up for 38-56 months,with an average time of 46 months.During the follow-up,37 patients had no tumor recurrence and 42 had tumor recurrence (32 with tumor extrahepatic metastasis and 10 with intrahepatic metastasis);36 had survival and 43 died;the 1-and 3-year overall survival rates were respectively 86.84％ and 63.25％,and 1-and 3-year tumorfree survival rates were respectively 62.31％ and 51.27％.(3) Prognostic factors analysis after liver transplantation:① Results of univariate analysis showed that preoperative alpha-fetoprotein (AFP),Child-Pugh score,maximum tumour dimension,capsular invasion,intravascular tumor thrombus,Edmonson pathological grading and expression of CUL4B were related factors affecting the 3-year overall survival rate of patients after liver transplantation for HCC [Hazard Ratio (HR) =2.17,3.36,3.66,2.43,2.19,3.36,2.84,95％ confidence interval(CI):1.17-4.04,1.53-7.42,2.10-6.42,1.33-4.17,1.08-9.04,1.58-7.59,1.17-6.32,P＜ 0.05].The preoperative alpha-fetoprotein (AFP),Child-Pugh score,maximum tumour dimension,capsular invasion,intravascular tumor thrombus,Edmonson pathological grading and expression of CUL4B were related factors affecting the 3-year tumor-free survival rate of patients after liver transplantation for HCC (HR =2.06,3.72,3.16,2.36,2.83,3.21,1.69,95％CI:1.34-4.85,1.72-8.63,1.79-7.31,1.46-4.86,1.19-8.63,1.19-7.92,1.06-4.87,P＜0.05).② Results of multivariate analysis showed that maximum tumour dimension,intravascular tumor thrombus and expression of CUL4B were independent factors affecting the 3-year overall survival rate of patients after liver transplantation for HCC [Odds ratio(OR) =3.43,3.69,2.81,95％CI:1.16-6.02,1.96-9.38,1.04-9.63,P＜0.05].The maximum tumour dimension,intravascular tumor thrombus and expression of CUL4B were independent factors affecting the 3-year tumor-free survival rate of patients after liver transplantation for HCC (OR=2.25,4.72,2.74,95％C1:1.16-4.02,1.98-9.47,1.03-7.10,P＜ 0.05).The 3-year overall survival rate in patients with high-and low-expressions of CUL4B was respectively 66.7％ and 32.8％,with a statistically significant difference (x2 =5.69,P＜0.05).The 3-year tumor-free survival rate in patients with high-and low-expressions of CUL4B was respectively 73.3％ and 18.6％,with a statistically significant difference (x2 =4.63,P＜0.05).(4) Association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantation:results of Pearson test showed that expression of CUL4B was significantly associated with HCC recurrence and metastasis after liver transplantation (r =0.62,P＜0.05).The further analysis showed that expression of CUL4B was significantly associated with extrahepatic metastasis after liver transplantation (r=0.84,P ＜ 0.05).Conclusion The expression of CUL4B is associated with HCC recurrence after liver transplantation,and it can be as a predictor for HCC recurrence and distant metastasis after liver transplantation.

Comparison of the toxic effect of methamidophos and acephate on acetylcholinesterase / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the inhibitory effects of highly toxic organophosphorus compound and its substitute (methamidophos and acephate) on acetylcholinesterase (AChE) and their toxic mechanisms.</p><p><b>METHODS</b>Ellman method was used to measure AChE activity in vitro and vivo.</p><p><b>RESULTS</b>Acephate and methamidophos could directly inhibit AChE activities in human erythrocyte membrane and rat brain synatosomal membrane in dose- and time-dependent manners in vitro, and this effect was irreversible. The IC50 of acephate and methamidophos affecting human erythrocyte membrane and rat synatosomal membrane were approximately 10(-4) mol/L and 10(-5) mol/L respectively and the Ki were 10(2) mol.L-1.min-1 and 10(3) mol.L-1.min-1 respectively. In vivo, after rats being administered with them for 5 d, the inhibitory rate of AChE activities in blood were increased to 68.24% and 54.80% respectively. When rats being administrated with acephate, there was 31.68% of inhibition on the brain stem, but no significant inhibition in other brain region was noticed, while methamidophos had a strong inhibitory effect on the activity of AChE in all brain regions, especially the cerebellum and brain-stem(71.51% and 61.85% respectively).</p><p><b>CONCLUSION</b>Acephate and methamidophos could directly inhibit the AChE activities in vitro, but the inhibition degree was different. In vivo, both could also inhibit AChE activities in blood. The difference in inhibition on brain regions may be one of the reason of various toxic effect of them.</p>