[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.

Radiomics nomogram in aiding preoperatively dilatation and curettage in differentiating type II and type I endometrial cancer

AIM

To established a radiomics nomogram for improving the dilatation and curettage (D&C) result in differentiating type II from type I endometrial cancer (EC) preoperatively.

MATERIAL AND METHODS

EC patients (n=875) were enrolled retrospectively and divided randomly into a training cohort (n=437) and a test cohort (n=438), according to the ratio of 1:1. Radiomics signatures were extracted and selected from apparent diffusion coefficient (ADC) maps. A multivariate logistic regression analysis was used to identify the independent clinical risk factors. An ADC based-radiomics nomogram was built by integrating the selected radiomics signatures and the independent clinical risk factors. Decision curve analysis (DCA) was conducted to determine the clinical usefulness of the radiomics nomogram. The net reclassification index (NRI) and total integrated discrimination index (IDI) were calculated to compare the discrimination performances between the radiomics nomogram and the D&C result.

RESULTS

Receiver operating characteristic (ROC) curves showed that the clinical risk factors, the D&C, and the ADC based-radiomics nomogram yielded areas under the ROC curves (AUCs) of 0.70 (95% CI: 0.64-0.76), 0.85 (95% CI: 0.80-0.89), and 0.93 (95% CI: 0.90-0.96) in the training cohort and 0.64 (95% CI: 0.57-0.71), 0.82 (95% CI: 0.77-0.87) and 0.91 (95% CI: 0.87-0.95) in the test cohort, respectively. The DCA, NRI, and IDI demonstrated the clinically usefulness of the ADC based-radiomics nomogram.

CONCLUSION

The ADC-based radiomics nomogram could be used to improve the D&C result in differentiating type II from type I EC preoperatively.

[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.

Intervention effects of four exercise modalities on nonalcoholic fatty liver disease: a systematic review and Bayesian network meta-analysis

OBJECTIVE

This study aimed to evaluate the effect of four exercise modalities on patients with nonalcoholic fatty liver disease (NAFLD).

MATERIALS AND METHODS

Databases of CNKI, Wanfang, VIP, Web of Science, PubMed, Cochrane Library, Medline, and Embase were searched for relevant studies. The literature search was restricted to those published between January 2010 and June 2021. Randomized controlled trials of exercise interventions on NAFLD were collected. Data were presented as statistical graphics using ADDIS 1.16.5 and R-Studio 4.1.

RESULTS

Seventeen controlled studies analyzing 1627 patients with NAFLD were included. Patients were divided into the control group (n=688), aerobic training group (AT, n=554), resistance training group (RT, n=232), high-intensity interval training group (HIIT, n=53), and aerobic training with resistance training group (AT+RT, n=100). Results of the statistical analysis showed that the combined exercise intervention had the most significant effect on the total serum cholesterol of patients' mean difference [MD=0.47(0.23, 0.73), p<0.05]. Levels of alanine aminotransferase and aspartate aminotransferase were improved, but no significant difference was found in their levels in the four groups of exercise intervention. The intervention effect of the four exercises on blood lipid and liver enzymes in patients with NAFLD was in the order of AT+RT > HIIT > RT > AT > control.

CONCLUSIONS

Exercise interventions are recommended as stand-alone or adjunctive therapy. For patients with NAFLD who can tolerate various exercises, priority should be given to AT+RT exercise 4-5 times per week. The exercise intensity should be 50%-70% of the maximum heart rate and performed for >3 months to improve the effectiveness of the exercise supervision intervention.

[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.

Metformin plus megestrol acetate compared with megestrol acetate alone as fertility-sparing treatment in patients with atypical endometrial hyperplasia and well-differentiated endometrial cancer: a randomised controlled trial

OBJECTIVE

To assess the efficacy of metformin in megestrol acetate (MA)-based fertility-sparing treatment for patients with atypical endometrial hyperplasia (AEH) and endometrioid endometrial cancer (EEC).

DESIGN

A randomised, single-centre, open-label, controlled trial conducted between October 2013 and December 2017.

SETTING

Shanghai OBGYN Hospital of Fudan University, China.

POPULATION

A total of 150 patients (18-45 years old) with primary AEH or well-differentiated EEC were randomised into an MA group (n = 74) and an MA plus metformin group (n = 76).

METHODS

Patients with AEH or EEC were firstly stratified, then randomised to receive MA (160 mg orally, daily) or MA (160 mg orally, daily) plus metformin (500 mg orally, three times a day).

MAIN OUTCOMES AND MEASURES

The primary efficacy parameter was the cumulate complete response (CR) rate within 16 weeks of treatment (16w-CR rate); the secondary efficacy parameters were 30w-CR rate and adverse events.

RESULTS

The 16w-CR rate was higher in the metformin plus MA group than in the MA-only group (34.3 versus 20.7%, odds ratio [OR] 2.0, 95% confidence interval [CI] 0.89-4.51, P = 0.09) but the difference was more significant in 102 AEH patients (39.6 versus 20.4%, OR 2.56, 95% CI 1.06-6.21, P = 0.04). This effect of metformin was also significant in non-obese (51.4 versus 24.3%, OR 3.28, 95% CI 1.22-8.84, P = 0.02) and insulin-sensitive (54.8 versus 28.6%, OR 3.04, 95% CI 1.03-8.97, P = 0.04) subgroups of AEH women. No significant result was found in secondary endpoints.

CONCLUSION

As a fertility-sparing treatment, metformin plus MA was associated with a higher early CR rate compared with MA alone in AEH patients.

TWEETABLE ABSTRACT

For AEH patients, metformin plus MA might be a better fertility-sparing treatment to achieve a higher early CR rate compared with MA alone.

[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.

[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.

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.