Hotspots and difficulties of biliary surgery in older patients

ABSTRACT

With the accelerated aging society in China, the incidence of biliary surgical diseases in the elderly has increased significantly. The clinical characteristics of these patients indicate that improving treatment outcomes and realizing healthy aging are worthy of attention. How to effectively improve the treatment effect of geriatric biliary surgical diseases has attracted widespread attention. This paper reviews and comments on the hotspots and difficulties of biliary surgery in older patients from six aspects: (1) higher morbidity associated with an aging society, (2) prevention and control of pre-operative risks, (3) extending the indications of laparoscopic surgery, (4) urgent standardization of minimally invasive surgery, (5) precise technological progress in hepatobiliary surgery, and (6) guarantee of peri-operative safety. It is of great significance to fully understand the focus of controversy, actively make use of its favorable factors, and effectively avoid its unfavorable factors, for further improving the therapeutic effects of geriatric biliary surgical diseases, and thus benefits the vast older patients with biliary surgical diseases. Accordingly, a historical record with the highest age of 93 years for laparoscopic transcystic common bile duct exploration has been created by us recently.

Clinical studies of magnetic resonance elastography from 1995 to 2021: Scientometric and visualization analysis based on CiteSpace

BACKGROUND

To assess the knowledge framework around magnetic resonance elastography (MRE) and to explore MRE research hotspots and emerging trends.

METHODS

The Science Citation Index Expanded of the Web of Science Core Collection was searched on 22 October 2021 for MRE-related studies published between 1995 and 2021. Excel 2016 and CiteSpace V (version 5.8.R3) were used to analyze the downloaded data.

RESULTS

In all, 1,236 articles published by 726 authors from 540 institutions in 40 countries were included in this study. The top 10 authors published 57.6% of all included articles. The 3 most productive countries were the USA (n=631), Germany (n=202), and France (n=134), and the 3 most productive institutions were the Mayo Clinic (n=240), Charité (n=131), and the University of Illinois (n=56). The USA and the Mayo Clinic had the highest betweenness centrality among countries and institutions, respectively, and played an important role in the field of MRE. In this study, the 24,347 distinct references were clustered into 48 categories via reasonable clustering using specific keywords, forming the knowledge framework. Among the 294 co-occurring keywords, "hepatic fibrosis", "stiffness", "skeletal muscle", "acoustic strain wave", "in vivo", and "non-invasive assessment" were research hotspots. "Diagnostic performance", "diagnostic accuracy", "hepatic steatosis", "chronic hepatitis B", "radiation force impulse", "children", and "echo" were frontier topics.

CONCLUSIONS

Scientometric and visualized analysis of MRE can provide information regarding the knowledge framework, research hotspots, frontier areas, and emerging trends in this field.

How to select the quantitative magnetic resonance technique for subjects with fatty liver: A systematic review

BACKGROUND

Early quantitative assessment of liver fat content is essential for patients with fatty liver disease. Mounting evidence has shown that magnetic resonance (MR) technique has high accuracy in the quantitative analysis of fatty liver, and is suitable for monitoring the therapeutic effect on fatty liver. However, many packaging methods and postprocessing functions have puzzled radiologists in clinical applications. Therefore, selecting a quantitative MR imaging technique for patients with fatty liver disease remains challenging.

AIM

To provide information for the proper selection of commonly used quantitative MR techniques to quantify fatty liver.

METHODS

We completed a systematic literature review of quantitative MR techniques for detecting fatty liver, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Studies were retrieved from PubMed, Embase, and Cochrane Library databases, and their quality was assessed using the Quality Assessment of Diagnostic Studies criteria. The Reference Citation Analysis database (https://www.referencecitationanalysis.com) was used to analyze citation of articles which were included in this review.

RESULTS

Forty studies were included for spectroscopy, two-point Dixon imaging, and multiple-point Dixon imaging comparing liver biopsy to other imaging methods. The advantages and disadvantages of each of the three techniques and their clinical diagnostic performances were analyzed.

CONCLUSION

The proton density fat fraction derived from multiple-point Dixon imaging is a noninvasive method for accurate quantitative measurement of hepatic fat content in the diagnosis and monitoring of fatty liver progression.

Therapeutic experience of a pancreatic mixed serous neuroendocrine neoplasm invading peripancreatic vessels: A case report

RATIONALE

Pancreatic mixed serous neuroendocrine neoplasm (PMSNN) is an extremely rare disease. Only a few cases on the surgical treatment of PMSNN have been reported in the literature, and it is unclear whether there is invasion of important peripancreatic vessels.

PATIENT CONCERNS

We report the case of a 39-year-old female patient with PMSNN accompanied by invasion of important peripancreatic vessels. She underwent surgery and achieved satisfactory recovery.

DIAGNOSIS

Abdominal enhanced CT images showed an enhanced mass with a nonenhanced cyst involving the head and body of the pancreas, which invaded important peripancreatic vessels. The lesion had been misdiagnosed and mistreated as a metastatic carcinoma before admission.

INTERVENTIONS

CT 3-dimensional (3D) visualization reconstruction images showed intact peripancreatic vessels. Radical pancreatoduodenectomy was successfully performed and confirmed that the main blood vessels around the pancreas were only compressed or even wrapped by the mass, but not penetrated.

OUTCOMES

The patient recovered well and was discharged on the 19th day after surgery. Pathological examination reported the diagnosis of PMSNN with the collision type combination and the well-differentiated grade 2 pancreatic neuroendocrine tumor. She was followed up for 18 months without any abnormalities.

LESSONS

This case demonstrates that surgical treatment of PMSNN with invasion of peripancreatic vessels can be successful. Preoperative abdominal CT 3D visualization reconstruction is helpful in determining the degree of invasion of important peripancreatic vessels, and plays a key role in formulating an accurate surgical plan and improving patient outcome.

Critical values of monitoring indexes for perioperative major adverse cardiac events in elderly patients with biliary diseases

BACKGROUND

Major adverse cardiac events (MACE) in elderly patients with biliary diseases are the main cause of perioperative accidental death, but no widely recognized quantitative monitoring index of perioperative cardiac function so far.

AIM

To investigate the critical values of monitoring indexes for perioperative MACE in elderly patients with biliary diseases.

METHODS

The clinical data of 208 elderly patients with biliary diseases in our hospital from May 2016 to April 2021 were retrospectively analysed. According to whether MACE occurred during the perioperative period, they were divided into the MACE group and the non-MACE group.

RESULTS

In the MACE compared with the non-MACE group, postoperative complications, mortality, hospital stay, high sensitivity troponin-I (Hs-TnI), creatine kinase isoenzyme (CK-MB), myoglobin (MYO), B-type natriuretic peptide (BNP), and D-dimer (D-D) levels were significantly increased (P < 0.05). Multivariate logistic regression showed that postoperative BNP and D-D were independent risk factors for perioperative MACE, and their cut-off values in the receiver operating characteristic (ROC) curve were 382.65 pg/mL and 0.965 mg/L, respectively.

CONCLUSION

The postoperative BNP and D-D were independent risk factors for perioperative MACE, with the critical values of 382.65 pg/mL and 0.965 mg/L respectively. Consequently, timely monitoring and effective maintenance of perioperative cardiac function stability are of great clinical significance to further improve the perioperative safety of elderly patients with biliary diseases.

Protective and therapeutic experience of perioperative safety in extremely elderly patients with biliary diseases

To explore the protective and therapeutic measures of improving perioperative safety in extremely elderly patients with biliary diseases, so as to improve the therapeutic efficacy of surgery. A retrospective case–control study of 412 elderly patients with biliary diseases was carried out from July 2013 to July 2019. Seventy eight cases were divided into the high age (HA) group (≥80 years) and 334 into the middle–low age (MLA) group (60–79 years). In the HA compared with MLA group, 1. Preoperative coexisting diseases: the occurrence of coexisting coronary heart disease (CHD), hypertension, chronic bronchitis with emphysema, hypoproteinemia, and anemia were significantly increased; 2. Laboratory examinations: function of liver, kidneys, heart, lungs, and blood coagulation significantly declined; 3. Surgical procedures: open cholecystectomy with transcystic common bile duct (CBD) exploration significantly higher, while laparoscopic cholecystectomy significantly lower; 4. Operative effects: intraoperative blood loss, operation time, postoperative hospital stay, and length of hospitalization significantly increased or prolonged; 5. Postoperative complications: postoperative respiratory failure, pulmonary infection, anemia and electrolyte disorder significantly increased; 6. Therapeutic outcomes: no significant difference in the therapeutic effects. Although the surgical risk was significantly increased, there was no significant difference in the therapeutic efficacy in the HA compared with MLA group, suggesting that surgical treatment in extremely elderly patients with biliary diseases is safe and feasible. The key is to actively treat preoperative coexisting diseases, strictly adhere to surgical indications, reasonably select surgical procedures, precisely perform the operation, closely monitor and control intraoperative emergencies, timely prevent and treat postoperative complications, so as to improve the perioperative safety of extremely elderly patients with biliary diseases.

Combination of preoperative fibrinogen and D-dimer as a prognostic indicator in pancreatic ductal adenocarcinoma patients undergoing R0 resection

BACKGROUND

Patients with malignant tumors frequently exhibit hyperactivation of the coagulation system and secondary increased fibrinolytic activity. Fibrinogen and D-dimer are common indicators that are crucial in the coagulation/fibrinolysis system. Both indicators have been verified to have predictive value in the overall survival (OS) of many patients with solid malignancies.

AIM

To explore the prognostic significance of fibrinogen combined with D-dimer in pancreatic ductal adenocarcinoma (PDAC) patients undergoing radical R0 resection.

METHODS

We retrospectively analyzed the clinical data of 282 patients with PDAC undergoing radical R0 resection in the Cancer Hospital, Chinese Academy of Medical Sciences, between January 2010 and December 2019. The surv_cutpoint function of R language was used to determine the optimal cutoff values of the preoperative fibrinogen concentration and preoperative D-dimer concentration. Enrolled patients were further divided into the any-high group (high preoperative fibrinogen concentration and/or high preoperative D-dimer concentration) and the low-low group (low preoperative fibrinogen and D-dimer concentrations) according to the optimal cutoff values.

RESULTS

The optimal cutoff values of the preoperative fibrinogen concentration and preoperative D-dimer concentration were 3.31 g/L and 0.53 mg/L, respectively. Furthermore, multivariate Cox regression analysis showed that the preoperative fibrinogen concentration (HR: 1.603, 95%CI: 1.201-2.140, P = 0.001) and preoperative D-dimer concentration (HR: 1.355, 95%CI: 1.019-1.801, P = 0.036) exhibited obvious correlations with the OS of PDAC patients undergoing radical R0 resection. A prognostic analysis was further performed based on the subgroup results by using fibrinogen combined with D-dimer. The median OS duration of the low-low group (31.17 mo) was significantly longer than that of the any-high group (15.43 mo). Additionally, multivariate Cox regression analysis revealed that the degree of differentiation (P < 0.001), lymph node metastasis (HR: 0.663, 95%CI: 0.497-0.883, P = 0.005), preoperative CA19-9 level (HR: 1.699, 95%CI: 1.258-2.293, P = 0.001), adjuvant therapy (HR: 1.582, 95%CI: 1.202-2.081, P = 0.001) and preoperative combined grouping (HR: 2.397, 95%CI: 1.723-3.335, P < 0.001) were independent predictors of OS in PDAC patients undergoing radical R0 resection.

CONCLUSION

Preoperative fibrinogen combined with D-dimer plays a predictive role in OS, and low preoperative fibrinogen and D-dimer concentrations can indicate prolonged OS in PDAC patients undergoing radical R0 resection.

Therapeutic experience of an 89-year-old high-risk patient with incarcerated cholecystolithiasis: A case report and literature review

BACKGROUND

The global pandemic of coronavirus disease 2019 pneumonia poses a particular challenge to the emergency surgical treatment of elderly patients with high-risk acute abdominal diseases. Elderly patients are a high-risk group for surgical treatment. If the incarceration of gallstones cannot be relieved, emergency surgery is unavoidable.

CASE SUMMARY

We report an 89-year-old male patient with acute gangrenous cholecystitis and septic shock induced by incarcerated cholecystolithiasis. He had several coexisting, high-risk underlying diseases, had a history of radical gastrectomy for gastric cancer, and was taking aspirin before the operation. Nevertheless, he underwent emergency laparoscopic cholecystectomy, with maintenance of postoperative heart and lung function, successfully recovered, and was discharged on day 8 after the operation.

CONCLUSION

Emergency surgery for elderly patients with acute abdominal disease is safe and feasible during the coronavirus disease 2019 pandemic, the key is to abide strictly by the hospital’s epidemic prevention regulations, fully implement the epidemic prevention procedure for emergency surgery, fully prepare before the operation, accurately perform the operation, and carefully manage the patient postoperatively.

Therapeutic experience of severe and recurrent secondary hyperparathyroidism in a patient on hemodialysis for 18 years: A case report

INTRODUCTION

For patients with refractory secondary hyperparathyroidism (SHPT), parathyroidectomy (PTX) has received increasing attention. However, evidence-based medicine shows that there is still controversy regarding surgical methods, efficacy, and safety. We retrospectively analyzed the process of diagnosis and treatment in one patient with severe SHPT and long-term chronic renal failure (CRF), so as to further improve the therapeutic effect.

CASE PRESENTATION

A 61-year-old female with SHPT and CRF manifested as no urine for 18 years, underwent PTX 4 times since September 2010, with satisfactory final recovery. The first operation involved resection of 3 parathyroid glands in the normal position; the second operation involved removal of an ectopic parathyroid gland, combined with parathyroid gland autotransplantation; the third operation was performed to resect suspected recurrent parathyroid gland; the fourth operation involved partial excision of the autotransplanted parathyroid glands.

CONCLUSION

Accurate preoperative localized diagnosis and optimal surgical approach play key roles in the prevention and treatment of SHPT; postoperative recurrence of SHPT caused by ectopic or autotransplanted parathyroid gland should receive more attention.

Strategies of minimally invasive treatment for intrahepatic and extrahepatic bile duct stones

Cholelithiasis is a kind of common and multiple diseases. In recent years, traditional laparotomy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and complications of minimally invasive treatment of intrahepatic and extrahepatic bile duct stones by combining our practical experience were summarized as follows. (1) For intrahepatic bile duct stones, the operation may be selected by laparoscopic liver resection, laparoscopic common bile duct exploration (LCBDE), or percutaneous transhepatic cholangioscopy. (2) For concomitant gallstones and common bile duct stones, the surgical approach can be selected as follows: laparoscopic cholecystectomy (LC) combined with endoscopic sphincterotomy (EST) or endoscopic papillary balloon dilatation, LC plus laparoscopic transcystic common bile duct exploration, LC plus LCBDE, and T-tube drainage or primary suture. (3) For concomitant intrahepatic and extrahepatic bile duct stones, laparoscopic liver resection, choledochoscopy through the hepatic duct orifice on the hepatectomy cross section, LCBDE, EST, and percutaneous transhepatic cholangioscopic lithotripsy could be used. According to the abovementioned principle, the minimally invasive treatment approach combined with the surgical technique and equipment condition will be significant in improving the therapeutic effect and avoiding the postoperative complications or hidden dangers of intrahepatic and extrahepatic bile duct stones.

Strategies for diagnosis and treatment of benign and malignant colorectal obstruction

Colorectal obstruction is one of the most common acute abdominal diseases in surgery department. Because of complex etiological factors, severe condition, and rapid progression, timely diagnosis and proper treatment are necessary for colorectal obstruction. By searching the literature and based on our experience in clinical practice, we performed a comprehensive and systematic analysis of the etiology, diagnosis and treatment of benign and malignant colorectal obstruction, and summarize the main points of diagnosis and treatment of benign and malignant colorectal obstruction as follows: identifying the etiology of benign and malignant colorectal obstruction; flexible application of colonography with meglumine diatrizoate, CT virtual endoscopy, and colonoscopy; preoperative colonoscopic drainage as a bridge to surgery; strict control of surgical indication; precise surgical procedures; and active symptomatic treatment. These measures are of important significance in improving the diagnosis and treatment of benign and malignant colorectal obstruction.

Ischemic or toxic injury: A challenging diagnosis and treatment of drug-induced stenosis of the sigmoid colon

A 48-year-old woman was admitted with 15-mo history of abdominal pain, diarrhea and hematochezia, and 5-mo history of defecation difficulty. She had been successively admitted to nine hospitals, with an initial diagnosis of inflammatory bowel disease with stenotic sigmoid colon. Findings from computed tomography virtual colonoscopy, radiography with meglumine diatrizoate, endoscopic balloon dilatation, metallic stent implantation and later overall colonoscopy, coupled with the newfound knowledge of compound Qingdai pill-taking, led to a subsequent diagnosis of ischemic or toxic bowel disease with sigmoid colon stenosis. The patient was successfully treated by laparoscopic sigmoid colectomy, and postoperative pathological examination revealed ischemic or toxic injury of the sigmoid colon, providing a final diagnosis of drug-induced sigmoid colon stenosis. This case highlights that adequate awareness of drug-induced colon stenosis has a decisive role in avoiding misdiagnosis and mistreatment. The diagnostic and therapeutic experiences learnt from this case suggest that endoscopic balloon expansion and colonic metallic stent implantation as bridge treatments were demonstrated as crucial for the differential diagnosis of benign colonic stenosis. Skillful surgical technique and appropriate perioperative management helped to ensure the safety of our patient in subsequent surgery after long-term use of glucocorticoids.

Therapeutic experience of 289 elderly patients with biliary diseases

AIM

To present clinical characteristics, diagnosis and treatment strategies in elderly patients with biliary diseases.

METHODS

A total of 289 elderly patients with biliary diseases were enrolled in this study. The clinical data relating to these patients were collected in our hospital from June 2013 to May 2016. Patient age, disease type, coexisting diseases, laboratory examinations, surgical methods, postoperative complications and therapeutic outcomes were analyzed.

RESULTS

The average age of the 289 patients with biliary diseases was 73.9 ± 8.5 years (range, 60-102 years). One hundred and thirty-one patients (45.3%) had one of 10 different biliary diseases, such as gallbladder stones, common bile duct stones, and cholangiocarcinoma. The remaining patients (54.7%) had two types of biliary diseases. One hundred and seventy-nine patients underwent 9 different surgical treatments, including pancreaticoduodenectomy, radical resection of hilar cholangiocarcinoma and laparoscopic cholecystectomy. Ten postoperative complications occurred with an incidence of 39.3% (68/173), and hypopotassemia showed the highest incidence (33.8%, 23/68). One hundred and sixteen patients underwent non-surgical treatments, including anti-infection, symptomatic and supportive treatments. The cure rate was 97.1% (168/173) in the surgical group and 87.1% (101/116) in the non-surgical group. The difference between these two groups was statistically significant (χ² = 17.227, P < 0.05).

CONCLUSION

Active treatment of coexisting diseases, management of indications and surgical opportunities, appropriate selection of surgical procedures, improvements in perioperative therapy, and timely management of postoperative complications are key factors in enhancing therapeutic efficacy in elderly patients with biliary diseases.

The strategies for treating primary hepatocellular carcinoma with portal vein tumor thrombus

PURPOSE

To further improve the effectiveness and prognosis of primary hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT), the current status of treatment for HCC with PVTT was reviewed.

METHODS

A Medline search was undertaken to identify articles using the keywords "HCC", "PVTT" and "therapy". Additional papers were identified by a manual search of the references from the key articles.

RESULTS

PVTT, as a common complication of HCC, was divided into type I ∼ IV. The therapeutic approach is mainly composed of five types: surgical resection, regional interventional therapy, radiotherapy, combination therapy, targeted therapy. All of these therapeutic approaches were separately evaluated in detail.

CONCLUSIONS

For those resectable tumors, the better choice for treatment of HCC with PVTT should be hepatectomy and removal of PVTT. For those unresectable tumors, TACE (especially the super-selective TACE) has been the preferred palliative treatment, the other regional interventional therapy and/or radiotherapy could improve the therapeutic effects. The multidisciplinary treatments may further improve the quality of life and prolong the survival period for the HCC patients associated with PVTT.

Preparation of magnetic resonance probes using one-pot method for detection of hepatocellular carcinoma

AIM: To prepare the specific magnetic resonance (MR) probes for detection of hepatocellular carcinoma (HCC) using one-pot method.

METHODS: The carboxylated dextran-coated nanoparticles were conjugated with anti-α-fetoprotein (anti-AFP) or anti-glypican 3 (anti-GPC3) antibodies through 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS)-mediated reaction to synthesize the probes. The physical and chemical properties of the probes were determined by transmission electron microscopy (TEM) and dynamic light scattering, and the relaxivity was compared to uncombined ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) using a 1.5T clinical MR scanner. The binding efficiency of the antibodies to nanoparticles was measured with an ultraviolet-visible spectrophotometer. In addition, the probes were incubated with targetable cells in vitro.

RESULTS: The superparamagnetic MR probes (anti-GPC3-USPION probe and anti-AFP-USPION probe) were synthesized using one-pot method. Their mean hydrodynamic diameter was 47 nm with a broader slight size distribution. The coupling efficiency of carboxylated dextran-coated ultrasmall superparamagnetic iron oxide (USPIO) with anti-GPC3 or anti-AFP antibody was 15.9% and 88.8%, respectively. Each of the USPIO nanoparticles may bind 3 GPC3 antibodies or 12 AFP antibodies. The statistical analysis showed no significance (P > 0.05) in shortening the T1 and T2 values when comparing the USPIO-AFP or USPIO-GPC3 to USPIO. Analysis of TEM images revealed that anti-GPC3-USPION probes and anti-AFP-USPION probes could specifically enter into the HepG2 cell by combining with the GPC3 receptors or AFP receptors, whereas the HepG2 cell sample incubated with USPIONs showed no or few nanoparticles in the cytoplasm.

CONCLUSION: The synthesized probes using one-pot method can be used for in vitro experimental study and have potential clinical application in MR imaging for detection of hepatocellular carcinomas.

Superparamagnetic iron oxide-enhanced magnetic resonance imaging for focal hepatic lesions: Systematic review and meta-analysis

AIM: To evaluate the performance of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) in the detection and characterization of focal hepatic lesions (FHLs).

METHODS: This meta-analysis compared relevant studies that were identified by searching PubMed, EMBASE, and the Cochrane Library databases for articles published between January 1988 and September 2014 and that met the following criteria: (1) SPIO-enhanced MRI was conducted to identify FHLs and data were sufficient for pooled analysis using Meta-DiSc 1.4; (2) hepatocellular carcinomas (HCCs) were differentiated from other FHLs; (3) well-differentiated HCCs (WD-HCCs) were contradistinguished from dysplastic nodules; and (4) WD-HCCs were compared with moderately and poorly differentiated HCCs (MD- and PD-HCCs, respectively).

RESULTS: The data obtained from 15 eligible studies yielded a sensitivity of 85% and a specificity of 78% for differentiating between HCCs and other FHLs. The sensitivity was unchanged and the specificity was increased to 87% when non-HCC malignancies were excluded. Comparative analyses between WD-HCCs and MD- and PD-HCCs from seven studies showed a sensitivity of 98% and a specificity of 50% for the diagnosis of MD- and PD-HCCs, and the area under the summary receiver operating characteristics (sROC) curve was 0.97. A comparison between WD-HCCs and dysplastic nodules revealed a sensitivity of 50% and a specificity of 92% for the diagnosis of WD-HCCs and the area under the sROC curve was 0.80.

CONCLUSION: SPIO-enhanced MRI is useful in differentiating between HCCs and other FHLs.

Mechanism of Roux-en-Y gastric bypass treatment for type 2 diabetes in rats

OBJECTIVES

Roux-en-Y gastric bypass (RYGB) is a novel therapy for diabetes. We aimed to explore the therapeutic mechanism of RYGB.

METHODS

After RYGB, animal models were established, and gene expression profile of islets was assessed. Additionally, gastrointestinal hormones were measured using enzyme-linked immunosorbent assays. Ca(2+) was studied using confocal microscopy and patch-clamp technique. The morphology of islets and beta cells was observed using optical microscopy and electron microscopy.

RESULTS

RYGB was an effective treatment in diabetic rats. Expression profiling data showed that RYGB produced a new metabolic environment and that gene expression changed to adapt to the new environment. The differential expression of genes associated with hormones, Ca(2+) and cellular proliferation was closely related to RYGB and diabetes metabolism. Furthermore, the data verified that RYGB led to changes in hormone level and enhanced Ca(2+) concentration changes and Ca(2+) channel activity. Morphological data showed that RYGB induced the proliferation of islets and improved the function of beta cells.

CONCLUSIONS

RYGB promoted a new metabolic environment while triggering changes to adapt to the new environment. These changes promoted the cellular proliferation of islets and improved the function of beta cells. The quantity of beta cells increased, and their quality improved, ultimately leading to insulin secretion enhancement.

Abnormal mitochondrial function impairs calcium influx in diabetic mouse pancreatic beta cells

BACKGROUND

Abnormal insulin secretion of pancreatic beta cells is now regarded as the more primary defect than the insulin function in the etiology of type 2 diabetes. Previous studies found impaired mitochondrial function and impaired Ca(2+) influx in beta cells in diabetic patients and animal models, suggesting a role for these processes in proper insulin secretion. The aim of this study was to investigate the detailed relationship of mitochondrial function, Ca(2+) influx, and defective insulin secretion.

METHODS

We investigated mitochondrial function and morphology in pancreatic beta cell of diabetic KK-Ay mice and C57BL/6J mice. Two types of Ca(2+) channel activities, L-type and store-operated Ca(2+) (SOC), were evaluated using whole-cell patch-clamp recording. The glucose induced Ca(2+) influx was measured by a non-invasive micro-test technique (NMT).

RESULTS

Mitochondria in KK-Ay mice pancreatic beta cells were swollen with disordered cristae, and mitochondrial function decreased compared with C57BL/6J mice. Ca(2+) channel activity was increased and glucose induced Ca(2+) influx was impaired, but could be recovered by genipin.

CONCLUSION

Defective mitochondrial function in diabetic mice pancreatic beta cells is a key cause of abnormal insulin secretion by altering Ca(2+) influx, but not via Ca(2+) channel activity.

Effects and mechanisms of store-operated calcium channel blockade on hepatic ischemia-reperfusion injury in rats

AIM

To further investigate the important role of store-operated calcium channels (SOCs) in rat hepatocytes and to explore the effects of SOC blockers on hepatic ischemia-reperfusion injury (HIRI).

METHODS

Using freshly isolated hepatocytes from a rat model of HIRI (and controls), we measured cytosolic free Ca(2+) concentration (by calcium imaging), net Ca(2+) fluxes (by a non-invasive micro-test technique), the SOC current (I(SOC); by whole-cell patch-clamp recording), and taurocholate secretion [by high-performance liquid chromatography and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays].

RESULTS

Ca(2+) oscillations and net Ca(2+) fluxes mediated by Ca(2+) entry via SOCs were observed in rat hepatocytes. I(SOC) was significantly higher in HIRI groups than in controls (57.0 ± 7.5 pA vs 31.6 ± 2.7 pA, P < 0.05) and was inhibited by La(3+). Taurocholate secretion by hepatocytes into culture supernatant was distinctly lower in HIRI hepatocytes than in controls, an effect reversed by SOC blockers.

CONCLUSION

SOCs are pivotal in HIRI. SOC blockers protected against HIRI and assisted the recovery of secretory function in hepatocytes. Thus, they are likely to become a novel class of effective drugs for prevention or therapy of HIRI patients in the future.

Preparation and in vitro studies of MRI-specific superparamagnetic iron oxide antiGPC3 probe for hepatocellular carcinoma

BACKGROUND

The aim of this study was to develop an antiGPC3-ultrasuperparamagnetic iron oxide (USPIO) probe for early detection of hepatocellular carcinoma.

METHODS

GPC3 and AFP receptors were selected as biomarkers and conjugated with USPIO nanoparticles coated by dextran with carboxylate groups to synthesize antiGPC3-USPIO and antiAFP-USPIO probes. HepG2 cells (a human hepatocellular carcinoma cell model with high expression of GPC3) were used along with SMMC-7721 cells (a hepatocellular carcinoma cell model with no expression of GPC3), HeLa cells (a cervical cancer model), and HL-7702 (normal hepatocytes) which were used as controls. After incubation with the probes, the iron content in the cells was calculated, USPIO nanoparticles in cells were observed using transmission electron microscopy, and T1 and T2 relaxation times were measured with a 1.5 T magnetic resonance scanner.

RESULTS

AntiGPC3-USPIO probes with a mean hydrodynamic diameter of 47 nm showed good biological compatibility. Transmission electron microscopic images indicated that the amount of USPIO nanoparticles taken up was significantly higher in HepG2 cells incubated with antiGPC3-USPIO than that in HepG2 cells incubated with antiAFP-USPIO or USPIO nanoparticles and that in the SMMC-7721 or HeLa cells incubated with antiGPC3-USPIO probes, antiAFP-USPIO probes, or USPIO nanoparticles. The higher the concentration and the longer the incubation time, the greater the number of USPIO nanoparticles found in the cells. No USPIO nanoparticles were found in the HL-7702 cells. All of the HepG2, SMMC-7721, and HeLa cells incubated with antiGPC3-USPIO, antiAFP-USPIO, or USPIO nanoparticles were able to shorten the T1 and T2 values in agar solution, especially the T2 images of HepG2 cells incubated with antiGPC3-USPIO probes.

CONCLUSION

AntiGPC3-USPIO probes can be utilized as a specific magnetic resonance targeting contrast agent for early detection of hepatocellular carcinoma. Using a 1.5 T magnetic resonance scanner, the optimal time for imaging HepG2 cells was around 2-4 hours after incubation with antiGPC3-USPIO probes.

Therapeutic options for intermediate-advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies, ranking the sixth in the world, with 55% of cases occurring in China. Usually, patients with HCC did not present until the late stage of the disease, thus limiting their therapeutic options. Although surgical resection is a potentially curative modality for HCC, most patients with intermediate-advanced HCC are not suitable candidates. The current therapeutic modalities for intermediate-advanced HCC include: (1) surgical procedures, such as radical resection, palliative resection, intraoperative radiofrequency ablation or cryosurgical ablation, intraoperative hepatic artery and portal vein chemotherapeutic pump placement, two-stage hepatectomy and liver transplantation; (2) interventional treatment, such as transcatheter arterial chemoembolization, portal vein embolization and image-guided locoregional therapies; and (3) molecularly targeted therapies. So far, how to choose the therapeutic modalities remains controversial. Surgeons are faced with the challenge of providing the most appropriate treatment for patients with intermediate-advanced HCC. This review focuses on the optional therapeutic modalities for intermediate-advanced HCC.

Functional interactions among STIM1, Orai1 and TRPC1 on the activation of SOCs in HL-7702 cells

STIM1, Orai1 and TRPC1 are all reported to be important for store-operated Ca(2+) entry (SOCE) in diverse cells. However, there is no evidence for the functional interaction of the three proteins in SOCE in human liver cells. The objective of this study is to determine whether they are involved in SOCE in normal human liver cells. Liposomal transfection method was used to increase expression levels of the three proteins in HL-7702 cells, a normal human liver cell line. Western blot and single cell RT-PCR were applied to evaluate transfection effectiveness. Changes in store-operated current (I(SOC)) and SOCE were investigated using whole-cell patch-clamp recording and calcium imaging. I(SOC) is detected in HL-7702 cells and it is inhibited either by 2-Aminoethoxydiphenyl borate (2-APB) or La(3+). Overexpression of STIM1 or Orai1 alone did not induce any change in I(SOC). TRPC1-transfection, however, caused approximate 2.5-fold increase in I(SOC). A large increase (>10-fold) in I(SOC) emerged when both STIM1 and Orai1 were co-transfected into HL-7702 cells. Co-overexpression of STIM1 + TRPC1 also caused >10-fold increase in I(SOC), and addition of Orai1 did not cause any further increase. In HL-7702 cells, TRPC1 and Orai1 take part in SOCE independently of each other. Functional interactions of STIM1 and Orai1 or TRPC1 contribute to I(SOC) activation.

Measuring Ca2+ influxes of TRPC1-dependent Ca2+ channels in HL-7702 cells with non-invasive micro-test technique

AIM

To explore the possibility of using the Non-invasive Micro-test Technique (NMT) to investigate the role of Transient Receptor Potential Canonical 1 (TRPC1) in regulating Ca(2+) influxes in HL-7702 cells, a normal human liver cell line.

METHODS

Net Ca(2+) fluxes were measured with NMT, a technology that can obtain dynamic information of specific/selective ionic/molecular activities on material surfaces, non-invasively. The expression levels of TRPC1 were increased by liposomal transfection, whose effectiveness was evaluated by Western-blotting and single cell reverse transcription-polymerase chain reaction.

RESULTS

Ca(2+) influxes could be elicited by adding 1 mmol/L CaCl(2) to the test solution of HL-7702 cells. They were enhanced by addition of 20 micromol/L noradrenaline and inhibited by 100 micromol/L LaCl(3) (a non-selective Ca(2+) channel blocker); 5 micromol/L nifedipine did not induce any change. Overexpression of TRPC1 caused increased Ca(2+) influx. Five micromoles per liter nifedipine did not inhibit this elevation, whereas 100 micromol/L LaCl(3) did.

CONCLUSION

In HL-7702 cells, there is a type of TRPC1-dependent Ca(2+) channel, which could be detected via NMT and inhibited by La(3+).

Comparative identification of Ca2+ channel expression in INS-1 and rat pancreatic beta cells

AIM

To identify and compare the profile of Ca(2+) channel subunit expression in INS-1 and rat pancreatic beta cells.

METHODS

The rat insulin-secreting INS-1 cell line was cultured in RPMI-1640 with Wistar rats employed as islet donors. Ca(2+) channel subunit expression in INS-1 and isolated rat beta cells were examined by reverse transcription polymerase chain reaction (RT-PCR). Absolute real-time quantitative PCR was performed in a Bio-Rad iQ5 Gradient Real Time PCR system and the data analyzed using an iQ5 system to identify the expression level of the Ca(2+) channel subunits.

RESULTS

In INS-1 cells, the L-type Ca(2+) channel 1C subunit had the highest expression level and the TPRM2 subunit had the second highest expression. In rat beta cells, the TPRC4beta subunit expression was dominant and the expression of the L-type 1C subunit exceeded the 1D subunit expression about two-fold. This result agreed with other studies, confirming the important role of the L-type 1C subunit in insulin-secreting cells, and suggested that non-voltage-operated Ca(2+) channels may have an important role in biphasic insulin secretion.

CONCLUSION

Twelve major Ca(2+) channel subunit types were identified in INS-1 and rat beta cells and significant differences were observed in the expression of certain subunits between these cells.

Effects of Ca2+ channel blockers on store-operated Ca2+ channel currents of Kupffer cells after hepatic ischemia/reperfusion injury in rats

AIM

To study the effects of hepatic ischemia/reperfusion (I/R) injury on store-operated calcium channel (SOC) currents (I(SOC)) in freshly isolated rat Kupffer cells, and the effects of Ca(2+) channel blockers, 2-aminoethoxydiphenyl borate (2-APB), SK and F96365, econazole and miconazole, on I(SOC) in isolated rat Kupffer cells after hepatic I/R injury.

METHODS

The model of rat hepatic I/R injury was established. Whole-cell patch-clamp techniques were performed to investigate the effects of 2-APB, SK and F96365, econazole and miconazole on I(SOC) in isolated rat Kupffer cells after hepatic I /R injury.

RESULTS

I/R injury significantly increased I(SOC) from -80.4 +/- 25.2pA to -159.5 +/- 34.5pA ((b)P < 0.01, n = 30). 2-APB (20, 40, 60, 80, 100 micromol/L), SK and F96365 (5, 10, 20, 40, 50 micromol/L), econazole (0.1, 0.3, 1, 3, 10 micromol/L) and miconazole (0.1, 0.3, 1, 3, 10 micromol/L) inhibited I(SOC) in a concentration-dependent manner with IC50 of 37.41 micromol/L (n = 8), 5.89 micromol/L (n = 11), 0.21 micromol/L (n = 13), and 0.28 micromol/L (n = 10). The peak value of I(SOC) in the I-V relationship was decreased by the blockers in different concentrations, but the reverse potential of I(SOC) was not transformed.

CONCLUSION

SOC is the main channel for the influx of Ca(2+) during hepatic I/R injuries. Calcium channel blockers, 2-APB, SK and F96365, econazole and miconazole, have obviously protective effects on I/R injury, probably by inhibiting I(SOC) in Kupffer cells and preventing the activation of Kupffer cells.

Effects of 2-APB on store-operated Ca2+ channel currents of hepatocytes after hepatic ischemia/reperfusion injury in rats

The effects of hepatic ischemia/reperfusion (1/R) injuries on hepatocellular viability and store-operated calcium current (Isoc) in isolated rat hepatocytes and the effects of 2-APB on store-operated calcium current (Isoc) in isolated rat hepatocytes after hepatic ischemia/reperfusion injuries were studied. Hepatic ischemia and reperfusion injury model was established and whole cell patch-clamp techniques were used to investigate the effects of 2-APB on Isoc. The results showed that ischemia/reperfusion injuries could significantly reduce hepatocellular viability and further increase Isoc in hepatocytes and 2-APB (20, 40, 60, 80, 100 micromol/L,) produced a concentration-dependent decrease of Isoc with IC50 value of 64. 63 +/- 10.56 micromol/L, (n = 8). It was concluded that ischemia/reperfusion injuries could reduce hepatocellular viability, probably through increased Isoc in hepatocytes and 2-APB had a protective effect on ischemia/reperfusion-induced liver injury, probably though inhibiting Isoc.

Hypocretin increases impulse flow in the septohippocampal GABAergic pathway: implications for arousal via a mechanism of hippocampal disinhibition

Hypocretins (Hcrts), or orexins, are a recently described set of hypothalamic peptides that have been implicated in feeding, neuroendocrine regulation, sleep-wakefulness, and disorders of sleep, such as narcolepsy. Hcrt-containing neurons, which are located exclusively in the lateral hypothalamic area, provide a dense innervation to the medial septum/diagonal band of Broca (MSDB), a sleep-associated brain region that has been suggested to show intense axonal degeneration in canine narcoleptics. The MSDB, via its cholinergic and GABAergic projections to the hippocampus, controls the hippocampal theta rhythm and associated learning and memory functions that occur during exploratory behavior and rapid eye movement sleep. Neurons of the MSDB express the Hcrt receptor 2, which is mutated in canine narcoleptics, but lack the Hcrt receptor 1 mRNA. In the present study, we investigated the electrophysiological effects of Hcrt2 on MSDB neurons from rat brain slices. We report that Hcrt2 produces a reversible, reproducible, concentration-dependent and direct postsynaptic excitation of GABA-type neurons of the MSDB with an EC50 of 207 nm. This effect is sodium dependent but not potassium or chloride dependent and is attenuated by blockers of the Na+-Ca+ exchanger. Hcrt2 also increases impulse-dependent release of GABA within the MSDB. Using recordings from retrogradely labeled septohippocampal neurons, we found that Hcrt2-excited MSDB neurons project to the hippocampus and have a GABAergic physiological signature. Double-immunolabeling studies confirmed the presence of Hcrt receptor-2 immunoreactivity in septohippocampal GABAergic neurons, as well as the presence of Hcrt fibers adjacent to these neurons. Based on these results, we speculate that Hcrt2-induced activation of septohippocampal GABAergic neurons will, by engaging disinhibitory mechanisms in the hippocampus, promote generation of the hippocampal theta rhythm and associated behaviors.

Identification of common binding sites for calmodulin and inositol 1,4,5-trisphosphate receptors on the carboxyl termini of trp channels

Homologues of Drosophila Trp (transient receptor potential) form plasma membrane channels that mediate Ca(2+) entry following the activation of phospholipase C by cell surface receptors. Among the seven Trp homologous found in mammals, Trp3 has been shown to interact with and respond to IP(3) receptors (IP(3)Rs) for activation. Here we show that Trp4 and other Trp proteins also interact with IP(3)Rs. The IP(3)R-binding domain also interacts with calmodulin (CaM) in a Ca(2+)-dependent manner with affinities ranging from 10 nm for Trp2 to 290 nm for Trp6. In addition, other binding sites for CaM and IP(3)Rs are present in the alpha but not the beta isoform of Trp4. In the presence of Ca(2+), the Trp-IP(3)R interaction is inhibited by CaM. However, a synthetic peptide representing a Trp-binding domain of IP(3)Rs inhibited the binding of CaM to Trp3, -6, and -7 more effectively than that to Trp1, -2, -4, and -5. In inside-out membrane patches, Trp4 is activated strongly by calmidazolium, an antagonist of CaM, and a high (50 microm) but not a low (5 microm) concentration of the Trp-binding peptide of the IP(3)R. Our data support the view that both CaM and IP(3)Rs play important roles in controlling the gating of Trp-based channels. However, the sensitivity and responses to CaM and IP(3)Rs differ for each Trp.

Increased inwardly rectifying potassium currents in HEK-293 cells expressing murine transient receptor potential 4

Drosophila transient receptor potential (Trp) and its mammalian homologues are postulated to form capacitative Ca2+ entry or store-operated channels. Here we show that expression of murine Trp4 in HEK 293 cells also leads to an increase in inwardly rectifying K+ currents. No similar increase was found in cell lines expressing Trp1, Trp3 or Trp6. Consistent with typical characteristics of inward rectifiers, the K+ currents in Trp4-expressing cells were blocked by low millimolar concentrations of Cs+ and Ba2+, but not by 1.2 mM Ca2+, and were only slightly inhibited by 5 mM tetraethylammonium. Single channel recordings of excised inside-out patches revealed the presence of two conducting states of 51 pS and 94 pS in Trp4-expressing cells. The outward current in the excised patches was blocked by 1 mM spermine, but not by 1 mM Mg2+. How Trp4 expression causes the increase in the K+ currents is not known. We propose that Trp4 either participates in the formation of a novel K+ channel or up-regulates the expression or activity of endogenous inwardly rectifying K+ channels.

Activation of Trp3 by inositol 1,4,5-trisphosphate receptors through displacement of inhibitory calmodulin from a common binding domain

Mammalian homologues of Drosophila Trp form plasma membrane channels that mediate Ca(2+) influx in response to activation of phospholipase C and internal Ca(2+) store depletion. Previous studies showed that human Trp3 is activated by inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)Rs) and identified interacting domains, one on Trp and two on IP(3)R. We now find that Trp3 binds Ca(2+)-calmodulin (Ca(2+)/CaM) at a site that overlaps with the IP(3)R binding domain. Using patch-clamp recordings from inside-out patches, we further show that Trp3 has a high intrinsic activity that is suppressed by Ca(2+)/CaM under resting conditions, and that Trp3 is activated by the following: a Trp-binding peptide from IP(3)R that displaces CaM from Trp3, a myosin light chain kinase Ca(2+)/CaM binding peptide that prevents CaM from binding to Trp3, and calmidazolium, an inactivator of Ca(2+)/CaM. We conclude that inhibition of the inhibitory action of CaM is a key step of Trp3 channel activation by IP(3)Rs.

Effects of beta-amyloid peptide on transient outward potassium current of acutely dissociated hippocampal neurons in CA1 sector in rats

OBJECTIVE

To explore the mechanism of beta-amyloid peptide (beta-AP) in Alzheimer's disease at ionic channel level.

METHODS

Hippocampal CA1 neurons of 7-21 days' rats were acutely dissociated and the effects of beta-AP on transient outward potassium current were observed by a whole-cell recording patch clamp technique.

RESULTS

beta-AP can significantly block transient potassium current in dose-dependent, time-dependent and partly voltage-dependent manners.

CONCLUSION

beta-AP may decrease the membrane conductance of K+ channels in hippocampal neurons, playing an important role in the pathophysiological mechanism of Alzheimer's disease.

Vasoactive intestinal peptide receptors in brains of hepatic encephalopathy rats. An experimental study

We evaluated the effect of vasoactive intestinal peptide (VIP) receptor, a brain-gut peptide receptor which is capable of exciting central neurons, on the pathogenesis of hepatic encephalopathy (HE). By means of radio-ligand binding assay, VIP receptors in the crude synaptosomal membranes of rat brains were investigated in rat models with HE induced by partial hepatectomy following carbon tetrachloride intoxication and in controls. The binding to the VIP receptor was studied, with 125I-VIP as a radioligand. Scatchard analysis of the binding data was linear, yielding a dissociation constant (Kd) of 0.28 +/- 0.01 nM and a maximal binding capacity (Bmax) of 9.56 +/- 0.29 fmol/mg of protein in HE rats. Only decreased Bmax values were observed (P < 0.002), while the Kd values were statistically unchanged (P > 0.20) in HE rats as compared with the controls. The results suggest that the changes of VIP receptors in the brains of HE rats play a significant role in the pathogenesis of HE. The mechanism of HE induced by the alterations of VIP receptors in the brains was discussed.

An experimental study on somatostatin receptors in the brains of hepatic encephalopathy rats

The present study was undertaken to evaluate the effect of somatostatin (SS) receptor, a brain-gut peptide receptor which is capable of inhibiting central neurons, on the pathogenesis of hepatic encephalopathy (HE). By means of radioligand binding assay, SS receptors in crude synaptosomal membrane of rat brains were investigated in a rat model of HE induced by partial hepatectomy following carbon tetrachloride intoxication and in controls. Binding to SS receptor was studied using 125 I-SS as radioligand. Scatchard analysis of binding data was linear, yielding a dissociation constant (Kd) of 3.99 +/- 0.22 nmol/L and a maximal binding capacity (Bmax) of 238 +/- 14.2 fmol/mg of protein in HE rats. Only increased Bmax values were observed (P < 0.005), while the Kd values were statistically unchanged (P > 0.50), in HE rats as compared with those in controls. The results suggest that the changes of SS receptors in brains play a significant role in the pathogenesis of HE. The mechanism of HE induced by the alterations of SS receptors in the brains was discussed in this paper.

Experimental studies on central benzodiazepine receptors in the brains of hepatic encephalopathy rats

With radioligand binding assay, we studied the central benzodiazepine receptors (CBR) in the different regions of brain including the telencephalon, diencephalon, brain stem and cerebellum in a rat model of hepatic encephalopathy (HE) induced by partial hepatectomy following carbon tetrachloride (CC1(4)) intoxication and in the controls. Affinities (Kd) and densities (Bmax) of [3H]-flunitrazepine binding to crude synaptic membranes in the telencephalon of HE rats were obviously increased as compared with those of the controls. It was only in the diencephalon, the brain stem and the cerebellum of HE rats that increased Bmax values were observed, while the Kd values remained unchanged. The results support the recent suggestion that the alterations of CBR play a significant role in the pathogenesis of HE. Among the ranges of the alterations of CBR in the HE rats, the telencephalon ranked first, the brain stem second, the cerebellum third, and the diencephalon last.