[The clinical value of further accurate staging of pT2 gastric cancer based on the depth of invasion]

Objective: To investigate the clinical value of pT2 gastric cancer staging pT2a and pT2b according to the depth of muscularis propria invasion in evaluating the prognosis of gastric cancer. Methods: According to the 8th edition of TNM staging system for gastric cancer proposed by the Union for International Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC), patients with gastric cancer who underwent radical surgery in the Fourth Hospital of Hebei Medical University from January 1, 2008 to January 1, 2015 were selected and divided into pT2a and pT2b stage group according to the depth of tumor invasion. The 5-year overall survival (OS) and disease-free survival (DFS) were compared between the two groups. Results: The median follow-up time of 1 411 patients with postoperative pathological pT2 stage was 68.8 months, and 1 347 patients (95.46%) received complete follow-up data. The 5-year OS rate was 65.85%, and the 5-year DFS rate was 67.83 %. The 5-year OS rate and 5-year DFS rate of 709 pT2a patients were 72.50% and 73.91%, respectively. The 5-year OS rate and 5-year DFS rate of 638 pT2b patients were 58.46% and 61.13%, respectively, significantly different from those of the pT2a group (P<0.001). Hierarchical analysis was performed according to N staging. The 5-year OS rates of pT2aN0M0 (274 cases), pT2aN1M0 (192 cases), pT2aN2M0 (147 cases), pT2aN3aM0 (59 cases) and pT2aN3bM0 (37 cases) were 83.58 %, 72.40 %, 68.71 %, 54.24 % and 35.12 %, respectively. The 5-year DFS rates were 84.67 %, 77.08 %, 67.35 %, 54.24 % and 35.14 %, respectively. In the pT2b group, the 5-year OS rates of pT2bN0M0 (209 cases), pT2bN1M0 (166 cases), pT2bN2M0 (127 cases), pT2bN3aM0 (78 cases) and pT2bN3bM0 (58 cases) were 76.08%, 62.05%, 56.69%, 37.18% and 17.24%, respectively, and the 5-year DFS rates were 80.86%, 69.28%, 54.33%, 35.90% and 15.52%, respectively. Under the same N stage, the OS rates of patients in the pT2a group were better than those in the pT2b group (P values were 0.023, 0.034, 0.034, 0.043 and 0.018, respectively). When the N stage was N0 and N1, there was no significant difference in the 5-year DFS rate between the pT2a group and the pT2b group (P values were 0.199 and 0.090, respectively). When the N stages were N2, N3a and N3b, the difference between the pT2a stage group and the pT2b stage group was statistically significant (P values were 0.027, 0.022 and 0.025, respectively). Conclusions: In the 8th edition of AJCC/UICC gastric cancer staging system, pT2 stage can be divided into pT2a stage (invasion of superficial muscularis) and pT2b stage (invasion of deep muscularis) according to the infiltration depth of muscularis propria. There are significant differences in prognosis between the two groups. Combined with the number of lymph node metastasis, the prognosis of patients with pT2 gastric cancer can be more accurately evaluated.

[The effect of cancer nodules on survival prognosis of gastric cancer patients]

Objective: To explore the relationship between cancer nodules and clinicopathological characteristics of gastric cancer, and analyze its impact on survival prognosis of gastric cancer patients. Methods: A retrospective analysis of 2 386 patients with gastric cancer who underwent radical surgery from January 1, 2012 to January 1, 2015 in the Third Surgery Department of the Fourth Hospital of Hebei Medical University was performed. The relationship between cancer nodules and clinicopathological characteristics of gastric cancer and its impact on survival prognosis of gastric cancer patients were analyzed. Results: Among the 2 386 patients, there were 459 cases (19.24%) with cancer nodules, and 1 927 cases (80.76%) without cancer nodules. Logistic multivariate analysis showed that pT staging (P=0.036), pN staging (P=0.024), pTNM staging (P=0.032), Borrmann classification (P=0.008), vascular tumor thrombus (P=0.001) were independent risk factors for cancer nodules. The complete follow-up date of 2 273 cases (95.26%) of 2 386 patients with gastric cancer were obtained. A total of 1 259 patients relapsed and 1 152 died during the follow-up period. The 5-years overall survival (OS) rate was 49.32%, and the 5-years disease-free survival (DFS) rate was 44.61%. Among them, the 5-years OS rate and DFS rate of those with cancer nodules were 26.76% and 24.94%, while the 5-years OS rate and DFS rate of those without cancer nodules were 54.75% and 49.34%, respectively (P<0.001). Patients with positive cancer nodules were divided into 3 groups according to the number of cancer nodules: 1 (115 cases), 2 to 3 (202 cases), and more than 4 (124 cases). The 5-years OS rates of 3 groups were 41.74%, 30.69% and 10.48%, respectively (P<0.001). The 5-years DFS rates were 40.00%, 28.22% and 9.68%, respectively (P<0.001). Cox multivariate analysis showed that histological type (P=0.004), pT staging (P=0.007), pN staging (P=0.004), pTNM staging (P=0.002), vascular tumor thrombus (P=0.034), cancer nodules (P=0.005) and the number of cancer nodules (P=0.001) were independent risk factors for the prognosis of gastric cancer patients, and postoperative adjuvant chemotherapy (P=0.043) was a protective factor for the prognosis of gastric cancer patients. Conclusion: Cancer nodules are closely related to the tumor stage and prognosis of gastric cancer patients. The number of cancerous nodules is an independent risk factor for the prognosis of gastric cancer patients.

[Application of laparoscopic exploration combined with abdominal exfoliative cytology in the diagnosis and treatment of locally advanced gastric cancer]

Objective: To explore the clinical significance of laparoscopic exploration combined with abdominal exfoliative cytology in the diagnosis and treatment of patients with locally advanced gastric cancer. Methods: Inclusion criteria: (1) cancer confirmed by gastroscopy and pathology without preoperative anti-tumor treatment; (2) no distant metastases found in preoperative imaging examinations; (3) patients without surgical contraindications and being tolerant to surgery; (4) patients were willing to undergo laparoscopic exploration and abdominal exfoliative cytology examination, and signed informed consent. A retrospective cohort study method was used to collect and analyze the clinicopathological data of 225 patients with advanced gastric cancer based on the above inclusion criteria from a prospective, multicenter, open, randomized controlled phase III clinical trial (registration No. NCT01516944) conducted between February 2012 and December 2018 in The Fourth Hospital of Hebei Medical University, including 162 males and 63 females with age ranged from 23 to 78 years old. Forty-five patients (20.0%) were classified as Borrmann type I to II, and 180 (80.0%) were classified as type III to IV. All the patients underwent laparoscopy and peritoneal lavage cytology under general anesthesia. Laparoscopic exploration sequence: left and right diaphragm→liver and spleen→parietal peritoneum→pelvic cavity→greater omentum, small intestine, mesentery→transverse colon mesentery →stomach. Contents of exploration: (1) with or without ascites; (2) whether metastatic lesions existed in the peritoneum, mesentery, omentum and Douglas pouch; (3) whether metastasis existed on the liver surface; (4) whether the gastric lymph nodes were swollen; (5) whether infiltration occurred on the gastric serosa surface; (6) whether gastric wall was stiff. The left and right subphrenic, the abdominal and pelvic peritoneum, and the mesentery were rinsed with 500 ml of sterilized normal saline. Position of the reverse Trendelenburg was used in the Douglas pouch. The peritoneal lavage fluid under the liver and spleen fossa was collected. Cytological examination was carried out for exfoliative tumor cells. Evaluation criteria: (1) peritoneal metastasis (P): P0 meant no peritoneal metastasis, P1 meant peritoneal metastasis; (2) free peritoneal cancer cells (CY): CY0 meant no cancer cells in peritoneal lavage fluid cytology, CY1 meant cancer cells in peritoneal lavage fluid cytology. The results of patients undergoing laparoscopic exploration combined with abdominal exfoliative cytology, treatment options and prognosis were analyzed. Kaplan-Meier method was used to calculate the survival rate and a survival curve was drawn. Log-rank test was used for survival analysis. Results: After laparoscopic exploration in 225 patients, clinical staging was corrected in 68 (30.2%) patients, of whom 7 (3.1%) downstaged and 61 (27.1%) increased in staging. Of 164 patients evaluated as P0CY0 after the first laparoscopy and peritoneal cytology examination, 126 underwent radical D2 surgery, and the other 38 patients were found to have later local lesions or extensive fusion of local lymph nodes, so then received neoadjuvant chemotherapy. Twenty-nine patients evaluated as P1CY0 or P1CY1 and 32 patients as P0CY1 underwent intraperitoneal hyperthermic chemotherapy+conversion therapy, and then a second laparoscopic exploration was performed to determine the treatment plan. In total, the original treatment regimens were changed after laparoscopic exploration in 99(44.0%) cases. The follow-up period ended in January 2019. The overall 2-year survival rate of 225 patients was 64.0%. As for those who were evaluated as P0CY0, P0CY1 and P1CY0-1 after the first laparoscopic exploration, the 2-year overall survival rate was 70.7%, 65.6% and 24.1%, respectively (P=0.002). The stratified analysis showed that among 180 patients with stage III tumor, after laparoscopic exploration combined with abdominal exfoliative cytology, 125 patients were found to be P0CY0, 28 were P0CY1, and 27 were P1CY0-1, whose 2-year overall survival rates were 70.4%, 64.3%, and 29.6% respectively, and the difference among these 3 groups was statistically significant (P=0.009). Conclusion: Laparoscopic exploration combined with abdominal exfoliative cytology in patients with locally advanced gastric cancer has important clinical guiding significance in improving accurate staging, treatment options and prognosis evaluation, and can avoid non-therapeutic open-close abdominal surgery.

[Effect of postoperative precision nutrition therapy on postoperative recovery for advanced gastric cancer after neoadjuvant chemotherapy]

Objective: To investigate the effect of postoperative precision nutrition therapy on postoperative recovery (PR) of patients with advanced gastric cancer (AGC) after neoadjuvant chemotherapy (NC). Methods: 71 subjects were randomly divided into 2 groups. The 34 patients of research group were treated with postoperative precision nutrition treatment according to the indirect energy measurement method. The 31 patients of control group were treated with traditional postoperative nutrition treatment. All participants were measured for body mass index (BMI), NRS2002, PG-SGA and relevant laboratory test within the 1st day before surgery and 7th day after surgery. Moreover, the difference between two groups in short-term effects were evaluated. Results: The daily energy supply of control group was 30.1%-43.74% higher than that of the experimental group (P<0.05). The resting energy expenditure (REE) of the research group after surgery was lower than that before operation. The levels of prealbumin, albumin and lymphocyte count were higher in research group than the controls at the 7th day after surgery whereas the opposite was true for the creatinine, urea nitrogen, C-reactive protein and procalcitonin (P<0.05). Similarly, the rate of malnutrition and nutritional risk became lower in the research group (P<0.05). The gastrointestinal function recovery of patients in the research group was comparable to that of the control group (P>0.05). Moreover, the complication rate and hospitalization costs of in research group were significantly lower than that of in control group (P<0.05). For patients with or without nutritional risks before surgery, the nutritional index and inflammatory index in the research group were better than those in the control group. Conclusion: Postoperative precision nutrition therapy may improve the postoperative nutritional status and short-term effects of patients with AGC after NC.

[Effects of transforming growth factor β1 receptor inhibitor SD-208 on human hypertrophic scar]

OBJECTIVE

To investigate the effects of transforming growth factor β1 (TGF-β1) receptor inhibitor SD-208 on human hypertrophic scar and its mechanisms.

METHODS

Scar fibroblasts were isolated from deprecated human hypertrophic scar tissue and then sub-cultured. Cells of the fifth passage were used in the following experiments. (1) Cells were divided into blank control group (BC) and 0.5, 1.0, 3.0, and 5.0 μmol/L SD-208 groups according to the random number table (the same grouping method below), with 6 wells in each group. Cells in group BC were added with 1 μL phosphate buffer solution, while cells in the latter four groups were added with 0.5, 1.0, 3.0, and 5.0 μmol/L SD-208, respectively. After being cultured for 12 hours, the proliferation activity of cells was detected by cell counting kit 8 and microplate reader (denoted as absorbance value). Suitable amount of substance concentration of SD-208 according to the results of proliferation activity of cells was chosen for the following experiments. (2) Another batch of cells were divided into group BC and 1, 3 μmol/L SD-208 groups and treated as in (1), with 8 wells in each group. The number of migration cells was detected by transwell method. (3) Another batch of cells were grouped and treated as in (2), and the microfilament morphology of cells was observed by rhodamine-phalloidin staining. (4) Another batch of cells were grouped and treated as in (2), and the protein expression of TGF-β1 was assessed with Western blotting. (5) Forty-eight BALB/c nude mice were divided into normal saline group (NS) and 1 μmol/L SD-208 group, and one longitudinal incision with length of 1 cm was made on their back. Then human hypertrophic scar tissue was embedded into the incision. On post injury day 7, multipoint injection of NS in a volume of 0.05 mL was performed in wounds of rats in group NS, while rats in 1 μmol/L SD-208 group were given 0.05 mL 1 μmol/L SD-208, once a day. On the day 0 (the same day), 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20 post first time of injection, the weight of 8 nude mice was weighed by electronic scale, and scar area was measured by vernier caliper and the ratio of rest scar area was calculated. (6) In week 1, 2, and 3 post first time of injection, the protein expression of TGF-β1 of human hypertrophic scar tissue was assessed with Western blotting. Data were processed with one-way analysis of variance and two independent-sample t test.

RESULTS

(1) The proliferation activity of cells in group BC, 0.5, 1.0, 3.0, and 5.0 μmol/L SD-208 groups was respectively 1.00±0.03, 0.90±0.08, 0.68±0.11, 0.54±0.04, and 0.42±0.09, and the proliferation activity of cells in 0.5, 1.0, 3.0, and 5.0 μmol/L SD-208 groups was significantly lower than that in group BC (with t values from 2.9 to 22.1, P<0.05 or P<0.01). (2) The number of migration cells in 1, 3 μmol/L SD-208 groups was significantly less than that in group BC (with t values respectively 6.5 and 6.4, P values below 0.01). (3) Compared with that in group BC, fluorescence intensity of microfilaments of cells in 1, 3 μmol/L SD-208 groups was attenuated, and the pseudopod extended less. (4) The protein expressions of TGF-β1 of cells in group BC and 1, 3 μmol/L SD-208 groups were respectively 1.00±0.08, 0.80±0.08, and 0.61±0.05, and the protein expressions of TGF-β1 of cells in 1, 3 μmol/L SD-208 groups were significantly lower than those in group BC (with t values respectively 4.0 and 9.2, P values below 0.01). (5) The weights of nude mice in group NS and 1 μmol/L SD-208 group were similar on each time day (with t values from 0.2 to 1.1, P values above 0.05). The ratios of rest scar area of nude mice in two groups were decreased along with the injection time, and the ratios of rest scar area of nude mice in 1 μmol/L SD-208 group were significantly less than those in group NS from the day 6 to 20 post first time of injection (with t values from 1.8 to 15.9, P<0.05 or P<0.01). In week 1, 2, and 3 post first time of injection, the protein expressions of TGF-β1 of human hypertrophic scar tissue in nude mice in two groups showed a tendency of decrease, and the protein expressions of TGF-β1 of human hypertrophic scar tissue in nude mice in 1 μmol/L SD-208 group were significantly lower than those in group NS (with t values from 6.2 to 19.1, P values below 0.01).

CONCLUSIONS

SD-208 has significant inhibition effect on human hypertrophic scars, and the mechanism is correlated to the inhibition of protein expression of endogenous TGF-β1.

Impact of Long-Term Irrigation with Treated Sewage on Soil Magnetic Susceptibility and Organic Matter Content in North China

This study assessed the effect on magnetic susceptibility and organic matter content of arable soil by irrigation with either treated sewage or groundwater. Results indicated that organic matter and magnetic susceptibility values in the soil irrigated with sewage were increased by 7.1 % and 13.5 %, respectively, compared to agricultural soil that irrigated with groundwater. Both the sewage and groundwater irrigated soils contained a significant fraction of ultrafine superpara magnetic grains, as indicated by high frequency dependent susceptibility (χfd > 6 %). The enhancement of soil magnetic properties was determined to be caused by anthropogenic sewage irrigation and agrochemical use by investigation of vertical soil profiles. Magnetic susceptibility parameters were shown to be significantly correlated with organic matter content (y = 0.0057x + 1.3439, R(2) = 0.09, p < 0.05). This work indicates that measurements of magnetic susceptibility may offer a rapid first step for identifying the potential pollution in arable soils.

Ribosomal DNA polymorphisms and the Oriental-Occidental genetic differentiation in cultivated barley

A total of 289 accessions of cultivated barley were assayed for ribosomal DNA (rDNA) polymorphisms. These accessions comprised four independent samples: (1) 79 entries from China, (2) 59 accessions from Ethiopia, (3) 59 entries from Tibet and (4) 92 entries representing 36 barley growing countries of the world (referred to as "world sample"). In all, 17 rDNA phenotypes (genotypes) were observed, which were composed 10 alleles at two rDNA loci, Rrn1 and Rrn2. The world sample contained the largest number of phenotypes and alleles and also demonstrated the highest level of diversity. Ribosomal DNA phenotypes 104, 112 and 107, 112 occurred at high frequencies worldwide. Allele 112 was the predominant allele of Rrn1 in all four samples, and 104 and 107 were the two major alleles of Rrn2 worldwide. The distributions of rDNA genotypes and alleles demonstrated a clear differentiation of two distinct barley groups: an Oriental group represented by the samples from China and Tibet, which is characterized by allele 107 at the Rrn2 locus (rDNA phenotype 107, 112); and an Occidental group, represented by Ethiopian and world samples, which is comprised mostly of allele 104 at the Rrn2 locus (rDNA phenotype 104, 112). The results also raised new questions concerning the phylogeny and evolution of cultivated barley.