[The safety and efficacy of prophylactic hyperthermic intraperitoneal chemotherapy for elderly patients with locally advanced gastric cancer: a propensity score matching analysis]

Objective: To evaluate the safety and efficacy of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) on elderly patients diagnosed with locally advanced gastric cancer based on a propensity score matching analysis. Methods: Clinical data of elderly patients with locally advanced gastric cancer who underwent radical gastrectomy in Beijing Hospital from January 2017 to December 2021 were retrospectively collected. According to whether HIPEC was used, the patients were divided into HIPEC group (radical gastrectomy combined with HIPEC) and control group (radical gastrectomy alone), and 29 patients in HIPEC group and 122 patients in control group. After 1∶1 matching of PSM, there were 28 patients in each group. The clinicopathological data, surgical data, postoperative recovery and long-term survival of the two groups were compared and analyzed. Results: Before PSM, the mean age in the HIPEC group was (70.7±4.0) years, and in the control group was (73.1±5.8) years (P=0.011). After PSM, the mean age in the HIPEC group was (70.9±3.9) years, and it was (71.8±5.4) years in the control group (P=0.739). Before PSM, the incidence of postoperative complications was 20.7% (6 cases) in the HIPEC group and 26.2% (32 cases) in the control group (P=0.639). After PSM, the incidence of postoperative complications was 21.4% (6 cases) in the HIPEC group and 14.3% (4 cases) in the control group (P=0.730). Before PSM, the mean duration of hospitalization after radical gastrectomy was (13.6±7.6) days in HIPEC group and (16.2±13.0) days in control group, respectively (P=0.312). After PSM, the mean duration of hospitalization after radical gastrectomy was (13.7±7.8) days in HIPEC group and (15.4±9.7) days in control group, respectively (P=0.479). Before PSM, the 1-and 3-year overall survival rates of the HIPEC group were 88.2% and 69.7%, and 88.0% and 66.1% for control group, respectively, with no statistical difference between the two groups in overall survival (P=0.499). After PSM, the 1-and 3-year overall survival rates of the HIPEC group were 86.8% and 69.7%, and 93.1% and 67.5% for control group, respectively, with no statistical difference between the two groups in overall survival (P=0.425). Before PSM, the 1-and 3-year disease-free survival rates of the HIPEC group were 88.2% and 67.1%, and 87.8% and 64.3% for control group, respectively, with no statistical difference between the two groups in disease-free survival (P=0.863). After PSM, the 1-and 3-year disease-free survival rates of the HIPEC group were 88.2% and 62.8%, and 93.7% and 64.7% for control group, respectively, with no statistical difference between the two groups in disease-free survival (P=0.804). Conclusions: Radical surgery combined with HIPEC for elderly patients with gastric cancer does not increase postoperative complications and postoperative recovery time. However, there was no significant difference in overall survival and disease-specific survival between the two groups.

[Analysis of prognosis and related factors in oldest-old patients with left-side or right-side colon cancer after hemicolectomy]

Objective: This study aimed to explore the difference of prognosis in oldest-old colon cancer patients between the left-side and right-side hemicolectomy. Methods: A total of 238 oldest-old (≥75 years old) colon cancer patients who received surgical treatment in Gastrointestinal Surgery Department of Beijing Hospital from December 2010 to December 2020 were retrospectively collected. They were divided into right-side hemicolectomy (RCC) group (130 cases) and left-side hemicolectomy (LCC) group (108 cases) by surgical methods. The difference in postoperative short-term complications and long-term prognosis was compared between the two groups, and the related factors of postoperative death was analyzed using multivariate Cox regression model. Results: The age of 238 oldest-old patients with colon cancer ranged from 75 to 93 years old (80.5±3.7). There were 128 males and 110 females. The ages of patients in the LCC group and RCC group were (80.4±3.7) and (80.6±3.7) years old (P=0.699), respectively. There was no significant difference in gender, body mass index (BMI) and co-existing chronic diseases between two groups (P>0.05). The proportion of the duration of surgery exceeding 170 min in the LCC group was significantly higher than that in the RCC group (56.5% vs 43.1%, P=0.039). The incidence of postoperative short-term complications in RCC group was slightly higher than LCC group (P>0.05), and there was no significant difference in overall survival (OS), tumor-specific survival (CSS) and disease-free survival (DFS) between two groups. However, the two groups had different prognostic risk factors, pathological Ⅳ stage (HR=28.970,95%CI:1.768-474.813,P=0.018), intraoperative bleeding (HR=2.297,95%CI:1.351-3.907,P=0.002) and cancer nodules (HR=2.044,95%CI:1.047-3.989,P=0.036) were independent prognostic risk factors in LCC group. Underweight (HR=0.428,95%CI:0.192-0.955,P=0.038), overweight(HR=0.316,95%CI:0.125-0.800,P=0.015),obesity (HR=0.211,95%CI:0.067-0.658,P=0.007), lymph node metastasis (HR=2.682,95%CI:1.497-4.807,P=0.001), tumor nodule (HR=2.507,95%CI:1.301-4.831,P=0.027) and postoperative length of stay of 9 days (HR=1.829,95%CI:1.070-3.128,P=0.006) were independent risk factors for poor prognosis in RCC group. Conclusions: The duration of surgery of oldest-old colon cancer patients in the LCC group was longer than that in the RCC group. However, there was no significant difference in the incidence of postoperative complications between the two groups. High pathological stage, more intraoperative bleeding and cancer nodules were independent prognostic risk factors in the LCC group. Abnormal BMI, lymph node metastasis, cancer nodules and postoperative length of stay were independent risk factors for poor prognosis in the RCC group.

[Contrastive analysis about the postoperative clinical characteristics of elderly patients with colorectal cancer in different age groups]

Objective: To explore the postoperative clinical characteristics of elderly patients with colorectal cancer at different ages. Methods: Retrospective analysis was performed on the clinical data of 720 elderly patients with Colorectal Cancer in Beijing Hospitals from January 2012 to December 2019. There were 411 males and 309 females with a median age of 74 years. We divided the patients into young-old, old-old, oldest-old colorectal cancer patient groups and used chi-square comparative analysis of different groups of patients with clinical disease characteristics. Results: The oldest-old colorectal cancer patients tended to have normal body mass index (BMI), and the site of the disease shifted to the right. The incidence of concomitant diseases such as heart disease and hypertension increases gradually with age, and the incidence of diabetes is highest in old-old colorectal cancer patients. The proportion of open surgery was higher in the oldest-old group, but the operation time was shorter than the other two groups. In addition, the incidence of postoperative complications in elderly patients with colorectal cancer gradually increases with age, especially cardiac complications and other complications such as pneumonia, deep venous thrombosis of lower limbs, urinary retention, urinary tract infection, renal failure, cerebral hemorrhage, cerebral infarction, and so on. Conclusions: The BMI of the oldest-old patients tended to be normal, and the site of the disease shifted to the right. The incidence of heart disease, hypertension, and other concomitant diseases and postoperative complications in elderly patients with colorectal cancer gradually increase with age. Thus, the choice of treatment should be more individualized for elderly patients with colorectal cancer, and more attention should be paid to perioperative management.

Laparoscopic vs open total gastrectomy for advanced gastric cancer following neoadjuvant therapy: A propensity score matching analysis

BACKGROUND

Laparoscopic total gastrectomy (LTG) has drawn increasing attention over the years. Although LTG has shown surgical benefits compared to open TG (OTG) in early stage gastric cancer (GC), little is known about the surgical and oncological outcomes of LTG for advanced GC following neoadjuvant therapy (NAT).

AIM

To compare the long- and short-term outcomes of advanced GC patients who underwent LTG vs OTG following NAT.

METHODS

Advanced GC patients who underwent TG following NAT between April 2011 and May 2018 at the Cancer Hospital of the Chinese Academy of Medical Sciences were enrolled and stratified into two groups: LTG and OTG. Propensity score matching analysis was performed at a 1:1 ratio to overcome possible bias.

RESULTS

In total, 185 patients were enrolled (LTG: 78; OTG: 109). Of these, 138 were paired after propensity score matching. After adjustment for propensity score matching, baseline parameters were similar between the two groups. Compared to OTG, LTG was associated with a significantly shorter length of hospital stay (P = 0.012). The rates of R0 resection, lymph node harvest, and postoperative morbidity did not significantly differ between the two groups. Overall survival (OS) outcomes were comparable between the two groups. Pathological T and N stages were found to be independent risk factors for OS.

CONCLUSION

LTG can be a feasible method for advanced GC patients following NAT, as it appears to be associated with better short- and comparable long-term outcomes compared to OTG.

Retrospective analysis of surgically treated pT4b gastric cancer with pancreatic head invasion

BACKGROUND

For advanced gastric cancer patients with pancreatic head invasion, some studies have suggested that extended multiorgan resections (EMR) improves survival. However, other reports have shown high rates of morbidity and mortality after EMR. EMR for T4b gastric cancer remains controversial.

AIM

To evaluate the surgical approach for pT4b gastric cancer with pancreatic head invasion.

METHODS

A total of 144 consecutive patients with gastric cancer with pancreatic head invasion were surgically treated between 2006 and 2016 at the China National Cancer Center. Gastric cancer was confirmed in 76 patients by postoperative pathology and retrospectively analyzed. The patients were divided into the gastrectomy plus en bloc pancreaticoduodenectomy group (GP group) and gastrectomy alone group (GA group) by comparing the clinicopathological features, surgical outcomes, and prognostic factors of these patients.

RESULTS

There were 24 patients (16.8%) in the GP group who had significantly larger lesions (P < 0.001), a higher incidence of advanced N stage (P = 0.030), and less neoadjuvant chemotherapy (P < 0.001) than the GA group had. Postoperative morbidity (33.3% vs 15.3%, P = 0.128) and mortality (4.2% vs 4.8%, P = 1.000) were not significantly different in the GP and GA groups. The overall 3-year survival rate of the patients in the GP group was significantly longer than that in the GA group (47.6%, median 30.3 mo vs 20.4%, median 22.8 mo, P = 0.010). Multivariate analysis identified neoadjuvant chemotherapy [hazard ratio (HR) 0.290, 95% confidence interval (CI): 0.103–0.821, P = 0.020], linitis plastic (HR 2.614, 95% CI: 1.024–6.675, P = 0.033), surgical margin (HR 0.274, 95% CI: 0.102–0.738, P = 0.010), N stage (HR 3.489, 95% CI: 1.334–9.120, P = 0.011), and postoperative chemoradiotherapy (HR 0.369, 95% CI: 0.163–0.836, P = 0.017) as independent predictors of survival in patients with pT4b gastric cancer and pancreatic head invasion.

CONCLUSION

Curative resection of the invaded pancreas should be performed to improve survival in selected patients. Invasion of the pancreatic head is not a contraindication for surgery.

Feasibility of totally laparoscopic gastrectomy without prophylactic drains in gastric cancer patients

BACKGROUND

Prophylactic drains have been used to remove intraperitoneal collections and detect complications early in open surgery. In the last decades, minimally invasive gastric cancer surgery has been performed worldwide. However, reports on routine prophylactic abdominal drainage after totally laparoscopic distal gastrectomy are few.

AIM

To evaluate the feasibility performing totally laparoscopic distal gastrectomy without prophylactic drains in selected patients.

METHODS

Data of patients with distal gastric cancer who underwent totally laparoscopic distal gastrectomy with and without prophylactic drainage at China National Cancer Center/Cancer Hospital from February 2018 to August 2019 were reviewed. The outcomes between patients with and without prophylactic drainage were compared.

RESULTS

A total of 457 patients who underwent surgery for gastric cancer were identified. Of these, 125 patients who underwent totally laparoscopic distal gastrectomy were included. After propensity score matching, data of 42 pairs were extracted. The incidence of concurrent illness was higher in the drain group (42.9% vs 31.0%, P = 0.258). The overall postoperative complication rates were 19.5% and 10.6% in the drain (n = 76) and no-drain groups (n = 49), respectively; there were no significant differences between the two groups (P > 0.05). The difference between the two groups based on the need for percutaneous catheter drainage was also not significant (9.8% vs 6.4%, P = 0.700). However, patients with a larger body mass index (≥ 29 kg/m²) were prone to postoperative complications (P = 0.042). In addition, the number of days from surgery until the first flatus (4.33 ± 1.24 d vs 3.57 ± 1.85 d, P = 0.029) was greater in the drain group.

CONCLUSION

Omitting prophylactic drainage may reduce surgery time and result in faster recovery. Routine prophylactic drains are not necessary in selected patients. A prophylactic drain may be useful in high-risk patients.

Progress and controversy in treatment of gastric cancer patients with positive peritoneal lavage cytology

Gastric cancer is one of the most common malignant tumors in China, and peritoneal metastasis is common in patients with gastric cancer. Positive peritoneal lavage cytology indicates a special type of distant metastasis of gastric cancer, and its therapeutic principle is still unclear. At present, the cornerstone treatment for advanced gastric cancer is radical surgery combined with postoperative adjuvant chemotherapy, and conversion therapy is very important for gastric cancer patients with positive peritoneal lavage cytology. Negative conversion of peritoneal lavage can effectively improve the prognosis. Intraperitoneal hyperthermic perfusion chemotherapy and intraoperative intraperitoneal lavage provide new ideas for the treatment of such patients, which can effectively kill free cancer cells in the abdominal cavity. At present, most clinical studies on the principles of treatment of gastric cancer patients with positive peritoneal lavage cytology are retrospective with a small sample size. We recommend to conduct multidisciplinary MDT discussions and develop individualized treatment plans for these patients, and encourage them to participate in relevant clinical trials.

Low body mass index is an independent predictor of poor long-term prognosis among patients with resectable gastric cancer

BACKGROUND

The association between body mass index (BMI) and clinical outcomes remains unclear among patients with resectable gastric cancer.

AIM

To investigate the relationship between BMI and long-term survival of gastric cancer patients.

METHODS

This retrospective study included 2526 patients who underwent radical gastrectomy for gastric cancer between September 2013 and June 2018. The patients were divided into four groups: Group A (low BMI, < 18.5 kg/m²), group B (normal BMI, 18.5-24.9 kg/m²), group C (overweight, 25-29.9 kg/m²), and group D (obese, ≥ 30 kg/m²). Clinicopathological findings and survival outcomes were recorded and analyzed.

RESULTS

Preoperative weight loss was more common in the low-BMI group, while diabetes was more common in the obese group. Upper-third gastric cancer accounted for a large proportion of cases in the higher BMI groups. Major perioperative complications tended to increase with BMI. The 5-year overall survival rates were 66.4% for group A, 75.0% for group B, 77.1% for group C, and 78.6% for group D. The 5-year overall survival rate was significantly lower in group A than in group C (P = 0.008) or group D (P = 0.031). Relative to a normal BMI value, a BMI of < 18.5 kg/m² was associated with poor survival (hazard ratio: 1.558, 95% confidence interval: 1.125-2.158, P = 0.008).

CONCLUSION

Low BMI, but not high BMI, independently predicted poor survival in patients with resectable gastric cancer.

Survival outcomes and prognostic indicators for gastric cancer patients with positive peritoneal wash cytology but no peritoneal metastasis after radical gastrectomy

BACKGROUND

Positive peritoneal wash cytology with no peritoneal metastasis (CY1P0) is a special type of distant gastric cancer metastasis, which describes a patient with positive peritoneal lavage cytology, but no definitive peritoneal metastasis, and there are no widely accepted treatment guidelines. We enrolled 48 primary CY1P0 gastric cancer patients treated by radical gastrectomy in this study. Our study illustrated the efficacy of radical gastrectomy for CY1P0 gastric cancer patients, and suggested that the pathological N factor and vascular invasion were significant independent risk factors for overall survival (OS).

AIM

To assess the survival of CY1P0 gastric cancer patient post-radical gastrectomy, and to identify factors associated with long-term prognosis.

METHODS

Our study included 48 patients with primary CY1P0 gastric cancer who had radical gastrectomies at the Cancer Hospital, Chinese Academy of Medical Sciences, Beijing, China between 2013 and 2018. R0 resection was achieved in all 48 patients. Twelve patients received neoadjuvant chemotherapy. Thirty patients received adjuvant chemotherapy and four received adjuvant chemoradiotherapy. OS statistics were available for 48 patients. Follow-up continued through March 2020. Univariate and multivariate analyses were performed using a Cox proportional hazards model to identify prognostic factors.

RESULTS

Median OS was 22.0 mo (95% confidence interval: 13.366-30.634 mo) post-surgery. Univariate analyses demonstrated that tumor site (P = 0.021), pathological N factor (P = 0.001), pathological T factor (P = 0.028), vascular invasion (P = 0.046), and the level of CA199 prior to initiating therapy (P = 0.002) were significant risk factors for OS. Multivariate analyses demonstrated that pathological N factor (P = 0.001) and vascular invasion (P = 0.031) were significant independent risk factors for OS.

CONCLUSION

This study suggested that radical gastrectomy may be efficient for CY1P0 gastric cancer patient post-radical gastrectomy and the pathological N factor and vascular invasion are significant independent risk factors for OS.

Feasibility and nutritional impact of laparoscopic assisted tailored subtotal gastrectomy for middle-third gastric cancer

BACKGROUND

Laparoscopic assisted total gastrectomy (LaTG) is associated with reduced nutritional status, and the procedure is not easily carried out without extensive expertise. A small remnant stomach after near-total gastrectomy confers no significant nutritional benefits over total gastrectomy. In this study, we developed a modified laparoscopic subtotal gastrectomy procedure, termed laparoscopic-assisted tailored subtotal gastrectomy (LaTSG).

AIM

To evaluate the feasibility and nutritional impact of LaTSG compared to those of LaTG in patients with advanced middle-third gastric cancer (GC).

METHODS

We retrospectively analyzed surgical and oncological outcomes and postoperative nutritional status in 92 consecutive patients with middle-third GC who underwent radical laparoscopic gastrectomy at Department of Pancreatic Stomach Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College between 2013 and 2017. Of these 92 patients, 47 underwent LaTSG (LaTSG group), and the remaining underwent LaTG (LaTG group).

RESULTS

Operation time (210 ± 49.8 min vs 208 ± 50.0 min, P > 0.05) and intraoperative blood loss (152.3 ± 166.1 mL vs 188.9 ± 167.8 mL, P > 0.05) were similar between the groups. The incidence of postoperative morbidities was lower in the LaTSG group than in the LaTG group (4.2% vs 17.8%, P < 0.05). Postoperatively, nutritional indices did not significantly differ, until postoperative 12 mo. Albumin, prealbumin, total protein, hemoglobin levels, and red blood cell counts were significantly higher in the LaTSG group than in the LaTG group (P < 0.05). No significant differences in Fe or C-reaction protein levels were found between the two groups. Endoscopic examination demonstrated that reflux oesophagitis was more common in the LaTG group (0% vs 11.1%, P < 0.05). Kaplan–Meier analysis showed a significant improvement in the overall survival (OS) and disease free survival (DFS) in the LaTSG group. Multivariate analysis showed that LaTSG was an independent prognostic factor for OS (P = 0.048) but not for DFS (P = 0.054). Subgroup analysis showed that compared to LaTG, LaTSG improved the survival of patients with stage III cancers, but not for other stages.

CONCLUSION

For advanced GC involving the middle third stomach, LaTSG can be a good option with reduced morbidity and favorable nutritional status and oncological outcomes.

Treatment of afferent loop syndrome using fluoroscopic-guided nasointestinal tube placement: Two case reports

BACKGROUND

Afferent loop syndrome (ALS) is a rare mechanical complication that occurs after reconstruction of the stomach or esophagus to the jejunum, such as Billroth II gastrojejunostomy, Roux-en-Y gastrojejunostomy, or Roux-en-Y esophagoje-junostomy. Traditionally, an operation is the first choice for benign causes. However, for patients in poor physical condition who experience ALS soon after R0 resection, the type of treatment remains controversial. Here, we present an efficient conservative method to treat ALS.

CASE SUMMARY

Case 1 was a 69-year-old male patient who underwent total gastrectomy with Roux-en-Y jejunojejunostomy. On postoperative day (POD) 10 he developed symptoms of ALS that persisted and increased over 1 wk. Case 2 was a 59-year-old male patient who underwent distal gastrectomy with Billroth II gastrojejunostomy. On postoperative day POD 9 he developed symptoms of ALS that persisted for 2 wk. Both patients underwent fluoroscopic-guided nasointestinal tube placement with maintenance of continuous negative pressure suction. Approximately 20 d after the procedure, both patients had recovered well and were discharged from hospital after removal of the tube. At 3-mo follow-up, there were no signs of ALS in these two patients.

CONCLUSION

This is the first report of treating postoperative ALS by fluoroscopic-guided nasointestinal tube placement. Our cases demonstrate that this procedure is an effective and safe method to treat ALS that relieves patients’ symptoms and avoids complications caused by other invasive procedures.

Treatment strategies for gastric cancer during the COVID-19 pandemic

The coronavirus disease 2019 pandemic has become a major global public health problem. Governments are taking the necessary steps to reduce the movement of people to contain the spread of the virus. However, these measures have caused considerable distress to patients with gastric cancer who are newly diagnosed or are undergoing treatment. In addition to the cancer, they must deal with longer waiting times for surgery and poor communication with doctors. Furthermore, gastric cancer patients generally have low immunity and a poor nutritional status, so they are a high-risk group for infection with the novel coronavirus. Therefore, it is necessary to formulate reasonable outpatient management strategies to reduce the adverse effects of the pandemic on their treatment. We summarize the management strategies for patients with gastric cancer during the pandemic.

[The clinical value of totally laparoscopic stomach-partitioning gastrojejunostomy for malignant gastric outlet obstruction]

Objective: To explore the clinical value of totally laparoscopic stomach-partitioning gastrojejunostomy (TLSPGJ) for malignant gastric outlet obstruction. Methods: The clinical data of 9 gastric cancer patients who underwent TLSPGJ in Department of Pancreatic and Gastric Surgery, Cancer Hospital between September 2018 and September 2019 were retrospectively analyzed. Results: The mean operative blood loss of 9 cases were (13.3±5.0) ml, and the average operative time was (103.3±10.6) min. All patients received clear flow food on the first day after surgery. Postoperative first exhaust time was (3.1±0.8) days and the average postoperative hospital stay was (5.4±1.1) days. All of the 9 patients could tolerate semi-liquid food at discharge, and no postoperative complications such as bleeding or delayed gastric emptying occurred. Conclusion: TLSPGJ is an effective treatment for gastric output tract obstruction caused by malignant tumor.

[Comparison of short-term clinical outcome between laparoscopic distal pancreatectomy and open distal pancreatectomy]

Objective: To compare the short-term clinical effect between laparoscopic distal pancreatectomy (LDP) and open distal pancreatectomy (ODP). Methods: We performed a retrospective study on 161 patients who underwent pancreatectomy between September 2017 to December 2018 in the Department of Pancreatic and Gastric Surgery, Cancer Hospital of Chinese Academy of Medical Sciences. According to the mode of operation, the patients were divided into the LDP group (n=43) and the ODP group (n=118). To compare the short-term clinical effect and safety between the LDP group and the ODP group, the preoperative clinical data, intraoperative related index, postoperative complication, postoperative recovery index, preoperative and postoperative inflammatory index were analyzed. Results: The preoperative clinical characteristics between the LDP group and the ODP group were not statistically different (P>0.05). The intraoperative blood loss in LDP group was (194.19±241.83) ml, significantly less than (315.17±295.94) ml in ODP group (P<0.05), and the postoperative exhaust time in LDP group was (3.00±0.72) days, significantly shorter than (4.05±0.97) days in OPD group (P<0.001). The time to get out of bed in LDP group was (3.14±1.01) days, significantly shorter than (3.55±1.05) days in OPD group (P<0.05). The postoperative eating time in LDP group was (3.88±1.61) days, significantly shorter than (5.11±1.56) days in ODP group (P<0.001). The time of the drainage tube removal in LDP group was (8.44±1.93) days, significantly shorter than (9.82±3.70) days in ODP group (P<0.05). The postoperative hospital stay in LDP group was (9.65±3.57) days, significantly shorter than (11.99±6.57) days in ODP group (P<0.05). The mean operation time in LDP group was (168.65±55.45) min, shorter than (171.23±65.61) min in ODP group, but without significant difference (P>0.05). The incidences of non-pancreatic fistula-related complications in LDP group and ODP group were 16.3% and 11.0%, respectively, without statistical significance (P>0.05). The incidences of pancreatic fistula in LDP group and ODP group were 16.3% and 19.5%, respectively, without statistical significance (P>0.05). The total incidences of complications in LDP group and ODP group were 32.6% and 30.5%, respectively, without statistical significance (P>0.05). The preoperative and postoperative inflammatory indexes between these two groups were not statistically different (P>0.05). Conclusions: Compared with ODP, LDP has the advantages of less intraoperative blood loss, faster postoperative recovery, shorter postoperative hospital stays, without increased postoperative complications and prolonged operation time. LDP is a safe and feasible operation method, and its short-term clinical effect is better than that of ODP.

[Surgical treatment strategy for digestive system malignancies during the outbreak of COVID-19]

The outbreak of COVID-19 occurred in Wuhan, Hubei province of China, at the end of 2019, and spread rapidly across the country. After the outbreak of this disease, the overwhelming majority of cities have launched the "first level response" and the regular diagnosis and treatment of cancer patients are greatly affected. The digestive systemic cancer is the most common malignancy. Most patients are diagnosed in the advanced stage with poor prognosis. The epidemic of COVID-19 poses new challenges to diagnosis and treatment of the patients with digestive system malignancies. Based on the fully understanding of the characteristics of digestive system tumors, we should change the treatment strategy and adopt more reasonable treatment strategy timely during the epidemic period to minimize the adverse effects of the epidemic of COVID-19 on the treatment.

Lifestyle factors and long-term survival of gastric cancer patients: A large bidirectional cohort study from China

BACKGROUND

Lifestyle factors such as body mass index (BMI), alcohol drinking, and cigarette smoking, are likely to impact the prognosis of gastric cancer, but the evidence has been inconsistent.

AIM

To investigate the association of lifestyle factors and long-term prognosis of gastric cancer patients in the China National Cancer Center.

METHODS

Patients with gastric cancer were identified from the China National Cancer Center Gastric Cancer Database 1998-2018. Survival analysis was performed via Kaplan-Meier estimates and Cox proportional hazards models.

RESULTS

In this study, we reviewed 18441 cases of gastric cancer. Individuals who were overweight or obese were associated with a positive smoking and drinking history (P = 0.002 and P < 0.001, respectively). Current smokers were more likely to be current alcohol drinkers (61.3% vs 10.1% vs 43.2% for current, never, and former smokers, respectively, P < 0.001). Multivariable results indicated that BMI at diagnosis had no significant effect on prognosis. In gastrectomy patients, factors independently associated with poor survival included older age (HR = 1.20, 95%CI: 1.05-1.38, P = 0.001), any weight loss (P < 0.001), smoking history of more than 30 years (HR = 1.14, 95%CI: 1.04-1.24, P = 0.004), and increasing pTNM stage (P < 0.001).

CONCLUSION

In conclusion, our results contribute to a better understanding of lifestyle factors on the overall burden of gastric cancer and long-term prognosis. In these patients, weight loss (both in the 0 to 10% and > 10% groups) but not BMI at diagnosis was related to survival outcomes. With regard to other factors, smoking history of more than 30 years conferred a worse prognosis only in patients who underwent gastrectomy. Extensive efforts are needed to elucidate mechanisms targeting the complex effects of lifestyle factors.

Neoadjuvant chemotherapy vs upfront surgery for gastric signet ring cell carcinoma: A retrospective, propensity score-matched study

BACKGROUND

The benefit of neoadjuvant chemotherapy for patients with signet-ring cell carcinoma of the stomach is controversial.

AIM

To evaluate the perioperative and long-term outcomes of neoadjuvant chemotherapy for locally advanced gastric signet-ring cell carcinoma.

METHODS

This retrospective study identified patients with locally advanced signet-ring cell carcinomas of the stomach (cT3/4 and cN any) diagnosed from January 2012 to December 2017 by using the clinical Tumor-Node-Metastasis (cTNM) staging system. We performed 1:1 propensity score matching (PSM) to reduce bias in patient selection. The histologic and prognostic effects of neoadjuvant chemotherapy were assessed. The overall survival rates were used as the outcome measure to compare the efficacy of neoadjuvant chemotherapy vs surgery-first treatment in the selected patients.

RESULTS

Of the 144 patients eligible for this study, 36 received neoadjuvant chemotherapy, and 108 received initial surgery after diagnosis. After adjustment by PSM, 36 pairs of patients were generated, and baseline characteristics, including age, sex, American Society of Anesthesiologists score, tumor location, and cTNM stage, were similar between the two groups. The R0 resection rates were 88.9% and 86.1% in the surgery-first and neoadjuvant chemotherapy groups after PSM, respectively (P = 1.000). The median follow-up period was 46.4 mo. The 5-year overall survival rates of the neoadjuvant chemotherapy group and surgery-first group were 50.0% and 65.0% (P = 0.235), respectively, before PSM and 50% and 64.7% (P = 0.192), respectively, after PSM. Multivariate analyses conducted before and after PSM showed that NAC was not a prognostic factor.

CONCLUSION

Neoadjuvant chemotherapy provides no survival benefit in patients with locally advanced gastric signet-ring cell carcinoma. For resectable gastric signet-ring cell carcinoma, upfront surgery should be the primary therapy.

Identification of key genes and pathways in gastric signet ring cell carcinoma based on transcriptome analysis

BACKGROUND

Gastric signet ring cell carcinoma (GSRCC) is one of the most malignant tumors. It has the features of high invasiveness, rapid progression, and resistance to chemotherapy. However, systematic analyses of mRNAs have not yet been performed for GSRCC.

AIM

To identify key mRNAs and signaling pathways in GSRCC.

METHODS

A transcriptome analysis of two GSRCC and two non-GSRCC samples was performed in this study. Differentially expressed mRNAs and pathways were identified based on the KEGG and PANTHER pathway annotations. The interactive relationships among the differential genes were mapped with the STRING database. Quantitative real-time polymerase chain reaction was used to validate the key gene expression in GSRCC.

RESULTS

About 1162 differential genes (using a 2-fold cutoff, P < 0.05) were identified in GSRCC compared with non-GSRCC. The enriched KEGG and PANTHER pathways for the differential genes included immune response pathways, metabolic pathways, and metastasis-associated pathways. Ten genes (MAGEA2, MAGEA2B, MAGEA3, MAGEA4, MAGEA6, MUC13, GUCA2A, FFAR4, REG1A, and REG1B) were identified as hub genes in the protein-protein interaction network. The expression levels of five genes (MAGEA2, MAGEA3, MAGEA4, MAGEA6, and REG1B) showed potential clinical value.

CONCLUSION

We have identified the potential key genes and pathways in GSRCC, and these hub genes and pathways could be diagnostic markers and therapeutic targets for GSRCC.

Current controversies in treating remnant gastric cancer: Are minimally invasive approaches feasible?

The incidence of remnant gastric cancer (RGC) is still increasing. Minimally invasive approaches including endoscopic resection, laparoscopic and robotic approaches, and function-preserving gastrectomy have been utilized as curative treatment methods for primary gastric cancer. However, adhesions and anatomical alterations due to previous gastrectomy make the use of minimally invasive approaches complicated and difficult for RGC. Application of these approaches for the treatment of RGC is still controversial. Endoscopic submucosal dissection is a favorable alternative therapy for the resection of early gastric cancer that occurs in the remnant stomach and can prevent unnecessary complications. The majority of retrospective studies have shown that endoscopic submucosal dissection is an effective and oncologically safe treatment modality for RGC. Subtotal gastrectomy could serve as a function-preserving gastrectomy for patients with early RGC and improve postoperative late-phase function. However, there are only two studies that demonstrate the feasibility and oncological efficacy of subtotal gastrectomy for RGC. The non-randomized controlled trials showed that compared to open gastrectomy, laparoscopic gastrectomy for RGC led to better short-term outcomes and similar oncologic results. Because of the rarity of RGC, future multicenter studies are required to determine the indications of minimally invasive treatment for RGC.

Additional laparoscopic gastrectomy after noncurative endoscopic submucosal dissection for early gastric cancer: A single-center experience

BACKGROUND

The necessity of additional gastrectomy for early gastric cancer (EGC) patients who do not meet curative criteria after endoscopic submucosal dissection (ESD) is controversial.

AIM

To examine the clinicopathologic characteristics of patients who underwent additional laparoscopic gastrectomy after ESD and to determine the appropriate strategy for treating those after noncurative ESD.

METHODS

We retrospectively studied 45 patients with EGC who underwent additional laparoscopic gastrectomy after noncurative ESD from January 2013 to January 2019 at the Cancer Hospital of the Chinese Academy of Medical Sciences. We analyzed the patients’ clinicopathological data and identified the predictors of residual cancer (RC) and lymph node metastasis (LNM).

RESULTS

Surgical specimens showed RC in ten (22.2%) patients and LNM in five (11.1%). Multivariate analysis revealed that positive horizontal margin [odds ratio (OR) = 13.393, 95% confidence interval (CI): 1.435-125, P = 0.023] and neural invasion (OR = 14.714, 95%CI: 1.087-199, P = 0.043) were independent risk factors for RC. Undifferentiated type was an independent risk factor for LNM (OR = 12.000, 95%CI: 1.197-120, P = 0.035). Tumors in all patients with LNM showed submucosal invasion more than 500 µm. Postoperative complications after additional laparoscopic gastrectomy occurred in five (11.1%) patients, and no deaths occurred among patients with complications.

CONCLUSION

Gastrectomy is necessary not only for patients who have a positive margin after ESD, but also for cases with neural invasion, undifferentiated type, and submucosal invasion more than 500 µm. Laparoscopic gastrectomy is a safe, minimally invasive, and feasible procedure for additional surgery after noncurative ESD. However, further studies are needed to apply these results to clinical practice.

Surgical resection of gastric stump cancer following proximal gastrectomy for adenocarcinoma of the esophagogastric junction

BACKGROUND

Proximal gastrectomy (PG) is performed widely as a function-preserving operation for early gastric cancer located in the upper third of the stomach and is an important function-preserving approach for esophagogastric junction (EGJ) adenocarcinoma. The incidence of gastric stump cancer (GSC) after PG is increasing. However, little is known about the GSC following PG because very few studies have been conducted on the disease.

AIM

To clarify clinicopathologic features, perioperative complications, and long-term survival rates after the resection of GSC following PG.

METHODS

Data for patients with GSC following PG for adenocarcinoma of the EGJ diagnosed between January 1998 and December 2016 were retrospectively reviewed. Multivariate analysis was performed to identify factors associated with overall survival (OS). GSC was defined in accordance with the Japanese Gastric Cancer Association.

RESULTS

A total of 35 patients were identified. The median interval between the initial PG and resection of GSC was 4.9 (range 0.7-12) years. In 21 of the 35 patients, the tumor was located in a nonanastomotic site of the gastric stump. Total gastrectomy was performed in 27 patients; the other 8 underwent partial gastrectomy. Postoperative complications occurred in 6 patients (17.1%). The tumor stage according to the depth of tumor invasion was T1 in 6 patients, T2 in 3 patients, T3 in 9 patients, and T4 in 17 patients. Lymph node metastasis was observed in 18 patients. Calculated 1-, 3-, and 5-year OS rates were 86.5%, 62.3%, and 54.2%, respectively. Multivariate analysis showed advanced T stage to be associated with OS.

CONCLUSION

This study reveals the characteristics of GSC following PG for adenocarcinoma of the EGJ and suggests that a surgical approach can lead to a satisfactory outcome.

[Comparison of short-term outcomes of laparoscopy-assisted and totally laparoscopic distal gastrectomy for gastric cancer]

Objective: To assess the safety, feasibility and short-term outcome of totally laparoscopic distal gastrectomy(TLDG). Methods: Seventy-five patients who underwent laparoscopic distal gastrectomy in Cancer Hospital of Chinese Academy of Medical Science between August 2015 and April 2018 were enrolled in this study. A total of 46 laparoscopy-assisted distal gastrectomy (LADG) cases and 29 TLDG cases were included. The Short-term outcomes and safeties of the two groups were compared. Results: The operation time of TLDG group was significantly longer than that of LADG group (207±41 vs. 156±34 min, P<0.001), while the length of wound was shorter in the TLDG group (3.6±0.6 vs. 5.8±0.8 cm, P<0.001). The time to first flatus in TLDG group was (3.3±0.6) days, significantly shorter than (3.7±0.8) days in LADG group (P=0.034). There were no significant differences between the two groups in the estimated blood loss, intraoperative blood transfusion, extraction of gastric tube, drainage tube removal, interval of the first time to eat semi-liquid food, postoperative hospital stays, surgical complications, number of retrieved lymph nodes, proximal and distal resection margin lengths (all P>0.05). The white blood cell count at postoperative day 1 in the TLDG group was (10.96±1.96) ×10(9)/L, significantly lower than (12.49±3.46)×10(9)/L of the LADG group (P=0.017). While the CRP level at postoperative day 1 in the TLDG group were lower than that of LADG group, no statistical difference was observed (P=0.072). Conclusions: Our study shows that TLDG is safe and feasible. TLDG has better cosmesis, less blood loss, and faster recovery compared to LADG.

Liposarcoma of the stomach: Report of two cases and review of the literature

Liposarcoma of the stomach is extremely rare, and only 37 cases have been reported worldwide. We herein report two cases of liposarcoma of the stomach. The first patient was referred to our hospital with upper abdominal discomfort. The endoscopic examination revealed a tumor mass about 3 cm in diameter. The patient underwent a partial gastrectomy and had an uneventful recovery. The histopathological examination revealed a well-differentiated liposarcoma. The second patient had symptoms of upper abdominal discomfort combined with nausea and anorexia. Several palpable masses were found with endoscopy. Endoscopic submucosal dissection was the treatment used, and the postoperative course was uneventful. The histopathological diagnosis was a well-differentiated liposarcoma. The two patients did not undergo any adjuvant therapy. They are both currently in good condition without recurrence. Therefore, we believe that the outcome of liposarcoma of the stomach is positive, and surgical resection may be the first choice for treatment at present.

[Application of chest CT scan in gestational trophoblastic neoplasia with lung metastasis]

Objective: To explore the role of CT scan for the diagnosis of lung metastasis in stage Ⅲ gestational trophoblastic neoplasia (GTN) . Methods: To figure out the role of CT scan for lung metastasis in GTN initial diagnosis, treatment and follow-up, 93 GTN patients with lung metastasis from January, 2015 to December, 2016 were retrospectively analyzed in Obstetrics and Gynecology Hospital of Fudan University. Results: (1) Among 93 GTN patients with lung metastasis, 70 patients with the International Federation of Gynecology and Obstetrics (FIGO) score ≤6 were defined as low risk GTN and 23 patients score score ≥7 were defined as high risk GTN. Forty nine patients had negative chest X-ray findings and 39 cases with pulmonary lesions were identified both by chest X-ray compared to CT scan. Five cases were excluded due to no consensus could make for the results of chest X-ray. The true positive rate of chest X-ray for lung metastasis were 41% (29/70) in low risk GTN and 43% (10/23) in high risk GTN patients without statistical difference (χ(2)=0.090, P=0.925) . For those patients with positive chest CT scan and negative chest X-ray finding, pulmonary lesions in 32 (65%, 32/49) cases were blocked by heart, chest wall or diaphragm in chest X-ray. Seventeen (35%,17/49) patients with lung lesions less than 5 mm had negative chest X-ray results due to the lower sensitivity compared to CT scan. (2) In 88 patients with stage Ⅲ, 78 patients had successful initial treatment, but 4 of them were recurrence in twelve months follow-up. Ten patients were chemotherapy resistance for the initial treatment. The initial chemotherapy remission rate in low risk GTN patients was higher than that in high risk ones (χ(2)=4.911, P=0.027) . In 49 cases with negative chest X-ray, there was no correlation with the rate of remission,chemotherapy resistance and recurrence in stage Ⅲ patients (P>0.05) . (3) For those patients who had poorly response to initial chemotherapy, the diameters of lesions in lung were unchanged or increased during the treatment, form (5.1±4.1) mm to (7.4±2.8) mm. The pulmonary lesions were continuously shrunk from (7.8±5.3) mm to (4.7±4.4) mm for those patients with complete and partial remission including the recurrent GTN patients (Z=-2.713, P=0.007) . Conclusions: Patients with GTN in stage Ⅲ have down staging if only use chest X-ray for imaging at the initial diagnosis. Chest CT scan is recommended for primary imaging evaluation of FIGO staging in qualified medical organization. For those patients with persistent abnormal serum hCG level and negative chest X-ray, chest CT scan is strongly recommended to identify the persist or resistant lung lesions and follow up.

Elderly patients had more severe postoperative complications after pancreatic resection: A retrospective analysis of 727 patients

AIM

To examine the impact of aging on the short-term outcomes following pancreatic resection (PR) in elderly patients.

METHODS

A retrospective cohort study using prospectively collected data was conducted at the China National Cancer Center. Consecutive patients who underwent PR from January 2004 to December 2015 were identified and included. ‘Elderly patient’ was defined as ones age 65 and above. Comorbidities, clinicopathology, perioperative variables, and postoperative morbidity and mortality were compared between the elderly and young patients. Univariate and multivariate analyses were performed using the Cox proportional hazard model for severe postoperative complications (grades IIIb-V).

RESULTS

A total of 454 (63.4%) patients were < 65-years-old and 273 (36.6%) patients were ≥ 65-years-old, respectively. Compared to patients < 65-years-old, elderly patients had worse American Society of Anesthesiologists scores (P = 0.007) and more comorbidities (62.6% vs 32.4%, P < 0.001). Elderly patients had more severe postoperative complications (16.8% vs 9.0%, P = 0.002) and higher postoperative mortality rates (5.5% vs 0.9%, P < 0.001). In the multivariate Cox proportional hazards model for severe postoperative complications, age ≥ 65 years [hazard ratio (HR) = 1.63; 95% confidence interval (CI): 1.18-6.30], body mass index ≥ 24 kg/m² (HR = 1.20, 95%CI: 1.07-5.89), pancreaticoduodenectomy (HR = 4.86, 95%CI: 1.20-8.31) and length of operation ≥ 241 min (HR = 2.97; 95%CI: 1.04-6.14) were significant (P = 0.010, P = 0.041, P = 0.017 and P = 0.012, respectively).

CONCLUSION

We found that aging is an independent risk factor for severe postoperative complications after PR. Our results might contribute to more informed decision-making for elderly patients.

Neuroendocrine carcinoma of the gastric stump: A case report and literature review

We herein report a case of neuroendocrine carcinoma of the gastric stump found 47 years after Billroth II gastric resection for a benign gastric ulcer. A 74-year-old man was referred to another hospital with melena. Endoscopic examination revealed a localized ulcerative lesion at the gastrojejunal anastomosis. The diagnosis by endoscopic biopsy was neuroendocrine carcinoma. A total gastrectomy of the remnant stomach with D2 lymphadenectomy was performed at our hospital. The lesion invaded the subserosa, and metastasis was found in two of nine the lymph nodes retrieved. The lesion was positive for synaptophysin and chromogranin A, and the Ki-67 labeling index was 60%. The diagnosis of neuroendocrine carcinoma of the gastric stump was confirmed using World Health Organization 2010 criteria. Subsequently, the patient underwent one course of adjuvant chemotherapy with the etoposide plus cisplatin (EP) regimen; however, treatment was discontinued due to grade 3 myelosuppression. The patient showed lymph node metastasis in the region around the gastrojejunal anastomosis in the abdominal cavity 7 mo post-surgery. He then underwent radiotherapy and platinum-based combination chemotherapy; however, the disease progressed and liver recurrence was observed on follow-up computed tomography at 16 mo post-surgery. The patient then received chemotherapy with regimens used for the treatment of small cell lung cancer in first- and second-line settings. The patient died of disease progression 31 months after surgery.

Partial outlet obstruction of the rat bladder induces a stimulatory response on proliferation of the bladder smooth muscle cells

Outlet obstruction of the rat bladder induces hypertrophy/hyperplasia characterized by increases in bladder mass, smooth muscle content, and collagen deposition. In order to understand the mechanism of the outlet obstruction-induced hypertrophy and hyperplasia, we first determined the temporal pattern of changes in bladder mass after inducing the outlet obstruction. Histological analysis revealed that the smooth muscle cells with hypertrophy and hyperplasia, fibroblasts and connective tissue were increased in a time-dependent manner, corresponding to the temporal pattern observed in the changes in bladder mass, although the phase of changes in these tissue components was somewhat different. In order to further determine whether any proliferation-stimulatory factors were released from the bladder with obstruction in correspondence with increased bladder mass, soluble fractions were prepared from the bladders with outlet obstruction for 3-30 weeks, and their effects on proliferation of smooth muscle cells were examined. The soluble fractions prepared from the bladders at 3 to 14 weeks after obstruction slightly but significantly facilitated the proliferation of cultured smooth muscle cells, while the soluble fractions released after 20 weeks rather suppressed the proliferation. These results suggest that the initial increase in bladder mass might be in part due to the facilitated proliferation of smooth muscle cells of the bladder body induced by growth factors released into the soluble fractions, and that hypertrophy might then play a role in the increased bladder mass at later phases.

Identification of muscarinic receptor subtypes of cultured smooth muscle cells and tissue of human bladder body

BACKGROUND

Muscarinic receptor subtypes of cultured smooth muscle cells from the human bladder body were investigated by the receptor binding assay method. The result was compared with that obtained from the human bladder body tissue to confirm whether the receptor subtypes of the cells are not changed after several passages of cell culture.

METHODS

Inhibitory effects of various muscarinic antagonists on the binding of [3H]-N-methylscopolamine ([3H]-NMS) to membrane preparations obtained from cultured smooth muscle cells from the fourth subculture of the human bladder body were compared with those prepared from the human bladder body tissue and cells expressing human muscarinic receptor subtypes.

RESULTS

Binding-inhibition constants (pKi) for atropine, pirenzepine, methoctramine, 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP), oxybutynin and propiverine obtained from membrane preparations of cultured smooth muscle cells were 8.91, 6.35, 8.24, 8.53, 7.29 and 5.61, respectively. pKi values of these muscarinic receptor antagonists against the membrane preparation of human bladder body tissue were 9.08, 6.66, 8.05, 8.79, 7.53 and 6.04, respectively. pKi values of cultured smooth muscle cells and tissue from human bladder body were correlated closely with those of insect cells expressing the cloned human M2 receptor subtype.

CONCLUSION

The binding affinities for various muscarinic receptor antagonists of cultured human smooth muscle cells were maintained through the fourth subculture and it was suggested that the M2 receptor subtype is predominantly expressed in cultured smooth muscle cells of human bladder body as well as in tissue of the human bladder body.

Release of endothelial nitric oxide in coronary arteries by celiprolol, a beta(1)-adrenoceptor antagonist: possible clinical relevance

Mechanisms underlying celiprolol-induced vasodilatation were analyzed in isolated porcine coronary arteries. Celiprolol induced dose-related relaxation of the artery rings with endothelium, an effect which was suppressed by N(G)-nitro-L-arginine methylester (L-NAME), nitric oxide (NO) scavenger, guanylate cyclase inhibitor, endothelium denudation, and removal of Ca(2+). L-NAME contracted, and superoxide dismutase relaxed, the arteries only when the endothelium was preserved. Neither superoxide dismutase nor beta-adrenoceptor antagonists changed celiprolol-induced relaxations. Celiprolol increased the cyclic GMP content in the tissue. The release of NO from endothelium, estimated by the extracellular production of cyclic GMP in arteries incubated in medium containing guanylate cyclase and GTP, was augmented by celiprolol, and L-NAME abolished this action of celiprolol. It is concluded that celiprolol elicits relaxation by acting on sites other than beta-adrenoceptors in the endothelium and by releasing NO, which activates soluble guanylate cyclase in smooth muscle and produces cyclic GMP. Scavenging of superoxide anions from the endothelium does not seem to account for the induced relaxation.

Determination and bioimaging method for nitric oxide in biological specimens by diaminofluorescein fluorometry

A simple and sensitive assay and a cellular bioimaging method for nitric oxide (NO) were developed using a novel diaminofluorescein DAF-FM and its diacetate. DAF-FM is converted via an NO-specific mechanism to an intensely fluorescent triazole derivative. For the measurement of NO, the triazole derivative of DAF-FM was determined by reversed-phase high-performance liquid chromatography with fluorescence detection. In the presence of 1 microM DAF-FM, the concentrations of NOR-1, an NO donor, in the range of 2-200 nM were linearly related to the fluorescence intensity. This sensitive NO assay enabled us to detect the spontaneous and substance P-induced NO release from isolated porcine coronary arteries, both of which were dependent entirely on the NO synthase activity in vascular endothelial cells. We also obtained fluorescence images of cultured smooth muscle cells of the rat urinary bladder after loading with DAF-FM diacetate. In the cells pretreated with cytokines, the fluorescence intensity increased with time after DAF-FM loading. This increase in the fluorescence intensity was blocked by prior treatment of the muscle cells with an NO synthase inhibitor, N(G)-nitro-l-arginine methyl ester. Therefore, the present novel diaminofluorescein fluorometry should be useful not only for sensitive NO assay, but also for NO imaging in a variety of biological specimens.

Inhibition of depolarization-induced nitric oxide synthase activation by NS-7, a phenylpyrimidine derivative, in primary neuronal culture

Neuronal nitric oxide synthase (NOS) is considered to be involved in the pathogenesis of ischemic brain damage. In the present study, the effect of a novel neuroprotective phenylpyrimidine derivative, 4-(4-fluorophenyl)-2-methyl-6-(5-piperidinopentyloxy)pyrimidine hydrochloride (NS-7), on depolarization-stimulated NOS activity was examined in cultured neurons of mouse cerebral cortex. Various depolarizing stimuli such as veratridine, KCl, and N-methyl-D-aspartate increased the NOS activity determined by cyclic GMP formation. NS-7 concentration-dependently inhibited both the veratridine- and KCl-induced NOS activation with IC50 values of 9.3 and 9.6 microM, respectively. The reversal of KCl-evoked NOS activity by NS-7 was also observed under blockade of both ionotropic glutamate receptors and the Na+ channel with MK-801, 6-cyano-7-nitroquinoxaline-2,3-dione, and tetrodotoxin. In contrast, NS-7, even at 100 microM, did not affect N-methyl-D-aspartate-stimulated NOS activity, nor did it have any influence on NOS activity determined in the soluble fraction of rat hippocampus. Because NS-7 has already been shown to block both Na+ and Ca2+ channels, the present findings suggest that this compound inhibits depolarization-induced NOS activation by reducing Ca2+ influx through blockade of Na+ and Ca2+ channels in primary neuronal culture.

A novel cognition enhancer NS-105 modulates adenylate cyclase activity through metabotropic glutamate receptors in primary neuronal culture

The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10(-7) and 10(-6) M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins. Conversely, in pertussis toxin-pretreated neurons, NS-105 (10(-7)-10(-5) M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S, 3R-ACPD) produced similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and 1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10(-6) M) and 1S, 3R-ACPD (10(-4) M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate (L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10(-4) M) but not by NS-105 (10(-6) M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis.

Comparison of fluid volumes with whole bowel irrigation in a simulated overdose of ibuprofen

OBJECTIVE

To determine the effect of 2 different fluid volumes of polyethylene glycol whole bowel irrigation (WBI) solution on absorption of an ingested toxin in a simulated overdose model.

DESIGN

Prospective, randomized, crossover trial.

SETTING

Clinical research unit.

PARTICIPANTS

Nine adult men.

INTERVENTIONS

On 2 separate days, volunteers ingested approximately 75 mg/kg of ibuprofen. In treatment 1, 30 minutes after ingestion of ibuprofen, a 3-L WBI at 2 L/h was begun. This procedure was repeated in treatment 2 with an 8-L. WBI administered at 2 L/h. Fourteen timed serum samples were collected prior to and after drug ingestion for a 24-hour period and analyzed for ibuprofen concentration. The peak serum concentration, time to peak concentration, total area under the serum concentration-time curve (AUC), clearance, and volume of distribution were compared.

RESULTS

The mean +/- SD AUCs did not differ between the 3-L (1185.3 +/- 216.9 mg.h/L) and 8-L (1153.5 +/- 251.5 mg.h/L) treatments (p = 0.710). Time to peak serum concentration, peak serum concentration, clearance, and volume of distribution were comparable for the 2 treatments (p > 0.05).

CONCLUSIONS

These data indicated that a total WBI volume of 3 L would be expected to perform as well as 8 L administered at the same rate. We recommend that further research define the optimal dose of WBI in acute ingestion of toxins.

Low-volume whole bowel irrigation and salicylate absorption: a comparison with ipecac-charcoal

STUDY OBJECTIVE

To evaluate two methods of gastrointestinal decontamination, low-volume whole bowel irrigation (WBI) and activated charcoal, for their ability to prevent absorption of salicylate.

DESIGN

Randomized, two-phase crossover study.

SETTING

A clinical research unit in a university-based teaching hospital.

PATIENTS

Six healthy, volunteer men.

INTERVENTIONS

Subjects were assigned to receive 3000 ml WBI or syrup of ipecac 30 ml followed by activated charcoal 50 g in sorbitol, and were crossed over to the other treatment phase after 1 week. All treatments began 30 minutes after ingestion of 3.25 g aspirin. Urine was collected over 24 hours for analysis of total urinary excretion of salicylate. Serial blood samples were collected for salicylate determination and were subjected to pharmacokinetic analysis.

MEASUREMENTS AND MAIN RESULTS

Mean +/- SD recovery of salicylate were WBI 48.6 +/- 5.4% and ipecac-charcoal 37.0 +/- 2.6% from urine (p < 0.01).

CONCLUSION

Ipecac-charcoal produced a significantly lower salicylate absorption (peak concentration, AUC) than WBI (p < 0.01) and thus was superior to low-volume WBI.

Association of functional alteration in intracellular signal transduction systems with the occurrence of up-regulation of muscarinic receptors in primary cultured neurons

1. Alterations in intracellular biosignaling systems associated with the up-regulated muscarinic receptor were investigated using primary cultured neurons exposured to 10 nM atropine for 5 days. 2. In neurons treated with atropine, the response of PI turnover to muscarinic stimulation decreased in comparison with that in non-treated neurons. 3. The GTP gamma S-stimulated PI turnover also reduced in neurons possessing up-regulated muscarinic receptor, although phospholipase C activity was not different in these two types of neurons. 4. In addition, the long-term exposure (5 days) to atropine induced the increase in GTPase activity and [3H]GppNHp binding. 5. These results suggest that the decreased response of PI turnover to muscarinic stimulation may be attributed to the functional deterioration of G-protein itself and/or coupling between G-protein and phospholipase C. 6. The present results also strongly suggest that the accentuation of the function of G protein may occur in association with the up-regulation of muscarinic receptor.

Pharmacological characteristics of choline transport system in mouse cerebral cortical neurons in primary culture

The characteristics of [3H]choline transport with high affinity were investigated using primary cultured neurons obtained from the mouse cerebral cortex. [3H]Choline uptake was saturable as a function of extracellular [3H]choline concentration. Analysis by Lineweaver-Burk plot revealed that [3H]choline was transported into neurons by a high affinity transport system with a Km value of 19.8 +/- 0.8 microM and Vmax value of 0.334 +/- 0.022 nmol/mg protein/min. This high affinity transport of [3H]choline was significantly inhibited by the withdrawal of sodium from the incubation medium, incubation at low temperature (4 degrees C) and addition of metabolic inhibitors such as monoiodoacetate. These results indicate that the high affinity [3H]choline uptake in primary cultured neurons is sodium- and energy-dependent. Hemicholinium-3 also showed a competitive inhibition on the [3H]choline transport. Depolarization by high K+ induced an enhancement of the [3H]choline uptake in the presence of Ca2+. The crude synaptosomal fraction obtained from primary cultured neurons possessed approximately forty-fold higher synthesizing activity of [3H]acetylcholine from [3H]choline than that found in the homogenate preparation of cultured neurons. The present results strongly suggest that the primary cultured neurons used in this study possess a sodium- and energy-dependent high-affinity choline uptake system as well as a synthesizing system for acetylcholine. Possible usefulness of these neurons for investigating neuronal uptake of choline and its functional role in the biosynthesis of acetylcholine are also suggested.

Ontogeny of beta-adrenergic receptor-mediated cyclic AMP generating system in primary cultured neurons

The developmental changes in the beta-adrenergic receptor/cyclic AMP generating system were examined using mouse cerebral cortical neurons in primary culture. During neuronal growth in vitro, the number of binding sites for [3H]dihydroalprenolol (DHA) showed a tendency to increase (Bmax), while the affinity (Kd) for [3H]DHA did not show any noticeable changes. Basal and isoproterenol-stimulated adenylate cyclase activities as well as the activation of adenylate cyclase by 5'-guanylylimidodiphosphate (GppNHp), NaF and forskolin showed progressive and parallel increases during neuronal growth on a polylysine-coated surface. The treatment of primary cultured neurons with islet-activating protein (IAP), one of the pertussis toxins, attenuated the inhibitory effect of carbachol, a muscarinic agonist, on isoproterenol-induced activation of adenylate cyclase activity. These results indicate that primary cultured neurons possess a cyclic AMP generating system coupled with beta-adrenergic and muscarinic receptors, which is regulated via stimulatory and inhibitory GTP-binding proteins, respectively. The results described above also suggest that the beta-adrenergic receptor, stimulatory and inhibitory types of GTP-binding proteins and adenylate cyclase may develop in a parallel fashion during neuronal growth on a polylysine-coated surface.

Alterations in receptor-coupled second messenger systems at up-regulated muscarinic receptors: analysis using primary cultured neurons

The effect of a long-term exposure (5 days) to atropine on muscarinic acetylcholine receptors and receptor-coupled second messenger systems was investigated using mouse cerebral cortical neurons in primary culture. The long-term exposure of neurons to atropine (10 nM) induced increases in both the Bmax and Kd values of [3H]quinuclidinyl benzilate (QNB) binding to muscarinic acetylcholine receptors. Alterations in muscarinic receptor-coupled second messenger systems, such as phosphoinositide (PI) hydrolysis and cyclic GMP (cGMP) formation following a long-term exposure to atropine, were also examined. Carbachol-stimulated PI hydrolysis was found to be decreased by the exposure to atropine in spite of the increase of muscarinic receptors. In addition, a long-term exposure to atropine had no effect on carbachol-stimulated cGMP formation as well as on the rightward shift of the carbachol competition curve of [3H]QNB binding in the presence of GTP. These results suggest that the up-regulation in muscarinic cholinergic receptors induced by long-term exposure to atropine may involve not only the increase in number of muscarinic receptors but also the decreased responsiveness in muscarinic receptor-coupled second messenger systems.