Advantages of pulsed electric field ablation for COPD: Excellent killing effect on goblet cells.

Mucus hypersecretion resulting from excessive proliferation and metaplasia of goblet cells in the airways is the pathological foundation for Chronic obstructive pulmonary disease (COPD). Clinical trials have confirmed the clinical efficacy of pulsed electric field ablation (PFA) for COPD, but its underlying mechanisms is poorly understood. Cellular and animal models of COPD (rich in goblet cells) were established in this study to detect goblet cells' sensitivity to PFA. Schwan's equation was adopted to calculate the cells' transmembrane potential and the electroporation areas in the cell membrane. We found that goblet cells are more sensitive to low-intensity PFA (250 V/cm-500 V/cm) than BEAS-2B cells. It is attributed to the larger size of goblet cells, which allows a stronger transmembrane potential formation under the same electric field strength. Additionally, the transmembrane potential of larger-sized cells can reach the cell membrane electroporation threshold in more areas. Trypan blue staining confirmed that the cells underwent IRE rate was higher in goblet cells than in BEAS-2B cells. Animal experiments also confirmed that the airway epithelium of COPD is more sensitive to PFA. We conclude that lower-intensity PFA can selectively kill goblet cells in the COPD airway epithelium, ultimately achieving the therapeutic effect of treating COPD.

Magnetic Spiderman, a New Surgical Training Device: Study of Safety and Educational Value in a Liver Transplantation Surgical Training Program.

INTRODUCTION: Difficulties with liver transplantation (LT)-related surgical techniques are great challenges for young surgeons. Thus, young surgeons need to undergo systematic preclinical training. However, an optimal training system for LT is still lacking. This study aims to evaluate the safety and educational value of the Magnetic Spiderman (MS) during LT-related surgical techniques training, particularly during training for the preparation of the donor's liver and vascular reconstruction. METHODS: For the donor liver preparation training, the pulling force of the MS was measured using 16 porcine livers. Another 40 porcine livers were divided into two groups: MS group (used MS in the preparation of the liver) (n = 25) and manual group (took manual assistance in the preparation of the liver) (MA group, n = 15). In vascular reconstruction training, 25 pairs of porcine iliac veins were used to practice reconstruction. Five LT experts evaluated the MS for its use in LT-related surgical techniques training. RESULTS: During the donor liver preparation training, the number of assistants required in the MS group was significantly less than the number required in the MA group (0 vs. 1.8 ± 0.1; P < 0.001). However, the number of vasculature leaking points was similar between the two groups (0.2 ± 0.1 vs. 0.4 ± 0.2; P = 0.51). In vascular reconstruction training, the trainee alone could complete the vascular reconstruction training, with a reconstruction success rate of 80% (20/25). All five experts considered the MS a viable alternative to assistants, with the ability to facilitate single surgeon training for LT. Four out of five (80%) experts considered MS quite safe for surgery and effective at keeping the surgical field clear. CONCLUSION: MS can reduce the number of assistants to zero in LT-related techniques training without increasing the risk of the operation, thus facilitating training for LT.

Characterization of the PM2.5 concentration in surgical smoke in different tissues during hemihepatectomy and protective measures.

The characteristics of the PM2.5 concentration in surgical smoke produced by operating on different human tissues during hemihepatectomy were explored to provide a reference for protective measures. Our results showed that the highest concentration of PM2.5 produced by the electrosurgical knife was the liver tissue, followed by muscle, adipose, and vascular tissue. When the single-layer disposable medical mask, double-layer disposable medical mask, and surgical particulate respirator were used to cover the sampling port of the detector, the PM2.5 concentration for all tissue types could be reduced by approximately 40%, 55% and 75%, respectively. In the liver, the average concentration of PM2.5 produced by the ultrasonic scalpel was approximately twice that produced by the electrosurgical knife, suggesting that the air pollution around the chief surgeon caused by the ultrasonic scalpel is more serious than that caused by the electrosurgical knife. Much more protective work should be given for the liver-related surgery.

Pathophysiologic Characterization of a Novel Rabbit Model of Biliary Tract Infection-Derived Sepsis.

Biliary tract infection (BTI)-derived sepsis remains a serious problem with significant morbidity and mortality in the modern era of critical care management. Current animal models of BTI have relied mostly on injecting purified bacteria or their toxins into the biliary tract. These models do not fully reflect pathophysiology or disease processes of clinical cholangitis or cholecystitis. In the current study, we developed a novel model of BTI by performing cholecystocolonic anastomosis (CCA) in rabbits and characterized pathophysiologic changes in this model. This model is intended to mimic the clinical process of cholecystocolonic fistula with reflux cholangitis, a severe form of BTI. Adult male rabbits were subjected to BTI-derived sepsis through an anastomosis of the gall bladder to the colon (i.e., CCA). The animals were monitored for 7 days to record survival. In additional groups of animals, various bacterial, hemodynamic, histological and biochemical parameters were measured at 12, 24, 48 and 72 h after CCA. The anastomosis between the gallbladder and the colon required about 5-8 min to finish. The median survival time for rabbits after CCA was 96 h. The positive rates of bacterial culture at 72 h after CCA were 83.3% and 100% in the blood and liver, respectively. The most common microorganism was Escherichia coli followed by Enterococcus. Plasma Tumor Necrosis Factor-α (TNF-α), Lnterleukin-10 (IL-10), Lnterleukin-6 (IL-6), and High-mobility group box 1 protein (HMGB-1) levels were greatly elevated after CCA. The cardiac index and heart rate increased slightly at 12 h after CCA and then continued to decrease. Systemic hypotension developed 48 h after CCA. Histological studies showed reflux cholangitis with acute lung and kidney injury. Cholecystocolonic anastomosis produces polymicrobial sepsis in rabbits, which mimics many aspects of human BTI-derived sepsis. It is reproducible and easy to perform and may serve as an excellent model for future sepsis research.

Effects of Different 980-nm Diode Laser Parameters in Hepatectomy.

BACKGROUND AND OBJECTIVE: Despite the successful application of laser in animal experiments and clinics, the adjustment of laser parameters during surgery is still unclear. This study aimed to investigate the effect of different 980-nm diode laser parameters in hepatectomy. This could provide a clear protocol for using 980-nm diode laser in hepatectomy. STUDY DESIGN/MATERIALS AND METHODS: In total, 48 Sprague-Dawley rats were used to explore the effects of different 980-nm diode laser parameters in hepatectomy, by setting different parameter combinations. The rats were randomly divided into eight groups, including the continuous wave group and quasi-continuous wave group. The effects were assessed in terms of liver resection speed, extent of intraoperative bleeding, and thermal damage. RESULTS: In the quasi-continuous wave group, there was a significant difference in resection speed at the different laser parameters (P < 0.001); however, there was no significant difference in intraoperative bleeding and thermal damage. In the continuous wave group, there was a significant difference in resection speed, intraoperative bleeding, and thermal damage at different parameters. CONCLUSION: The study showed that the average power determined hemostasis efficiency and thermal damage, and peak power determined the liver resection speed, whereas the pulse width and repetition frequency are not independent factors. When using 980-nm diode laser in hepatectomy, the average power should be decreased to prove hemostasis efficiency in delicate operations, and the peak power should be decreased to accelerate the procedure without worsening thermal damage. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

10-mm Laparo-Endoscopic Single-Site Cholecystectomy Using Multiple Magnetically Anchored and Controlled Instruments.

BACKGROUND: To study the feasibility of laparo-endoscopic single-site (LESS) cholecystectomy through a 10-mm incision using a miniature magnetically anchored and controlled laparoscopy system and a grasper system. METHODS: The miniature magnetically anchored and controlled laparoscopy system consisted of a miniature magnetically anchored camera (MMAC), an external magnetic anchoring unit, and a vision output device. The camera weighed 9.8 g and measured Φ10 mm × 50 mm. The magnetically anchored and controlled grasper system consisted of a magnetically anchored grasper (MAG), an external magnetic anchoring unit, and a push-pull device. The MAG had a titanium alloy clip head and a magnetic tail. The laparoscopy system and grasper system were used simultaneously to perform LESS cholecystectomy through a single 10-mm incision in model canines. RESULTS: LESS cholecystectomy through a 10-mm incision using the MMAC and MAG was attempted in six dogs. The mean operative time was 85.75 ± 7.14 min. The operation was completed successfully in four cases, with failure occurring in one case due to gallbladder rupture and in another due to bile duct injury. The MMAC provided clear imaging, and the MAG provided sufficient exposure to perform the cholecystectomy. The use of multiple magnetically anchored and controlled instruments did not result in notable collisions. CONCLUSIONS: The designed MMAC and MAG system could be easily maneuvered. LESS cholecystectomy may be feasible through a single 10-mm incision with the simultaneous use of multiple magnetically anchored and controlled instruments.

Racial disparities in the survival time of patients with hepatocellular carcinoma and intrahepatic cholangiocarcinoma between Chinese patients and patients of other racial groups: A population-based study from 2004 to 2013.

The aim of the present study was to investigate the racial disparities in the presentation, treatment and survival time of patients with hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC) between Chinese and other racial groups from the Surveillance, Epidemiology, and End Results (SEER) database between January 1st 2004, and December 31st 2013. Key covariates, including clinical presentation, treatment and survival time, were recorded and compared, demonstrating the racial differences. Kaplan-Meier analysis and Cox regression models were performed to identify these disparities in survival time. A total of 30,954 patients were identified in the SEER database. Among these, 27,767 (89.7%) had HCC and 3,187 (10.3%) had ICC. In the HCC cohort, Chinese patients had the highest survival time. Compared with the mortality risk of Chinese patients, the mortality risk of Other Asian, non-Hispanic white, Hispanic and African-American patients increased by 16.8, 35.1, 28.3 and 33.3%, respectively. Compared with other groups, Chinese patients were more likely to present with localized stage, and without vascular invasion, adjacent invasion and metastasis. In the ICC cohort, the Chinese group had improved survival time, compared with the other groups following univariate analysis, although no significant differences were observed between Chinese and Other Asian and Hispanic patients following adjusting for contributing factors. Furthermore, there was no significant differences in the presentation between the groups, which differed from the HCC analysis. In conclusion, race/ethnicity was a significant independent prognostic factor in the HCC cohort, whereas it was not significant in the ICC cohort. The synergistic effect of contributing factors, including demographic, socioeconomic, biological and treatment differences, caused the racial disparity observed in primary liver cancer survival time.

A novel magnetic device for laparoscopic cholangiojejunostomy.

BACKGROUND: Laparoscopic cholangiojejunostomy (LCJ) with hand-sewn technique is technically difficult and requires a long time to master. The purpose of this study was to assess the feasibility of LCJ using a novel magnetic compression device (MCD) in dogs. METHODS: The concept of the purse-string technique of the circular stapler was used to design a novel MCD for LCJ. To test the feasibility of this MCD in a more clinically relevant situation, four dogs were subjected to bile duct ligation. When the diameter of their bile ducts reached 10 mm, LCJ using MCD was performed. The anastomotic time and expelling time of the magnets were assessed. RESULTS: In the clinically relevant model of bile duct obstruction in dogs, LCJ created with this MCD yielded patent anastomoses. The LCJ procedure using this novel MCD was simple, and the mean anastomotic time was 12.9 ± 1.73 min. All animals recovered smoothly after the operation without complications. All magnets spontaneously passed through the rectum in 14.5 ± 2.08 d after LCJ. CONCLUSIONS: LCJ in dogs using this novel MCD is feasible.

Miniature magnetically anchored and controlled camera system for trocar-less laparoscopy.

AIM: To design a miniature magnetically anchored and controlled camera system to reduce the number of trocars which are required for laparoscopy. METHODS: The system consists of a miniature magnetically anchored camera with a 30° downward angle, an external magnetically anchored unit, and a vision output device. The camera weighs 12 g, measures Φ10.5 mm × 55 mm and has two magnets, a vision model, a light source, and a metal hexagonal nut. To test the prototype, the camera was inserted through a 12-mm conventional trocar in an ex vivo real liver laparoscopic training system. A trocar-less laparoscopic cholecystectomy was performed 6 times using a 12-mm and a 5-mm conventional trocar. In addition, the same procedure was performed in four canine models. RESULTS: Both procedures were successfully performed using only two conventional laparoscopic trocars. The cholecystectomy was completed without any major complication in 42 min (38-45 min) in vitro and in 50 min (45-53 min) using an animal model. This camera was anchored and controlled by an external unit magnetically anchored on the abdominal wall. The camera could generate excellent image. with no instrument collisions. CONCLUSION: The camera system we designed provides excellent optics and can be easily maneuvered. The number of conventional trocars is reduced without adding technical difficulties.

Splenorenal shunt via magnetic compression technique: a feasibility study in canine and cadaver.

INTRODUCTION: The concept of magnetic compression technique (MCT) has been accepted by surgeons to solve a variety of surgical problems. In this study, we attempted to explore the feasibility of a splenorenal shunt using MCT in canine and cadaver. MATERIAL AND METHODS: The diameters of the splenic vein (SV), the left renal vein (LRV), and the vertical interval between them, were measured in computer tomography (CT) images obtained from 30 patients with portal hypertension and in 20 adult cadavers. The magnetic devices used for the splenorenal shunt were then manufactured based on the anatomic parameters measured above. The observation of the anatomical structure showed there were no special structural tissues or any important organs between SV and LRV. Then the magnetic compression splenorenal shunt procedure was performed in three dogs and five cadavers. Seven days later, the necrotic tissue between the two magnets was shed and the magnets were removed with the anchor wire. RESULTS: The feasibility of splenorenal shunt via MCT was successfully shown in both canine and cadaver, thus providing a theoretical support for future clinical application.

Mass Continuous Suture versus Layered Interrupted Suture in Transverse Abdominal Incision Closure after Liver Resection.

BACKGROUND: Abdominal incision closure technique seriously influences patient prognosis. Most studies have focused on the different suture techniques and materials on midline incision, while little data are available in wide transverse or oblique incisions after liver resection (LR). The aim of the present study is to compare the two major incision suture methods after LR in our institute: Mass continuous suture (group P) and layered interrupted suture (group S). STUDY DESIGN: 258 patients undergoing LR with abdominal transverse or oblique incisions were prospectively enrolled. They were divided into two groups according to different abdominal incision suture methods and compared with the preoperative, intraoperative parameters, and postoperative wound complications. RESULTS: There were 118 patients in group P and 140 patients in group S, which was similar in general condition, primary disease, liver, and renal function. Incision length, total operation time, intraoperative blood loss, or perioperative antibiotics use were not different between the two groups. However, abdominal incision closure time and interval time for stitches removing after operation was significantly shorter in group P than group S (both p < 0.001). After a median follow-up of 16 months, the incidence of wound infection and fat liquefaction was more than two times higher in group S than group P, which, however, was not statistically different. Moreover, there was no difference in wound disruption or incisional hernia between the two groups. CONCLUSIONS: Although similar in occurrence of postoperative wound complications, mass continuous suture with polydioxanone seemed to be more timesaving in incision closure and motivated in wound healing.

[The Development of the Supermicroinvasive Magnetic Anchoring Laparoscopic System].

A magnetic anchoring supermicroinvasive laparoscopic system, including in vitro magnetic navigation handle and in vivo magnetic anchor laparoscopy is introduced. The magnetic anchor laparoscopic comprises an outer cannula, two data lines, a camera, a high color temperature LED light and two inner magnets. It is tiny enough to enter the abdominal cavity through conventional laparoscopic trocar and achieve orientation, navigation as wel as adjustment thefi eld of view within the abdominal cavity by attracting with the in vitro magnetic handle, thus it does not take up space of the laparoscopic trocar in working state. The system which can not only apply in single-port laparoscopic surgery based on a single traditional laparoscopic trocar but also apply in traditional laparoscopic surgery with less trocar, wil enhance the extent of minimaly invasive surgery and reduce the operation diffi culty at the same time. The clinical application of the system wil optimize the minimaly invasive techniques and benefi t the patients.

[The Current Status and Prospects of Single-Port Laparoscopic Flexible Instrument in Surgery].

In recent years, the emergence of single-port laparoscopic technology promoted the development of the technology of laparoscopy, but deficiencies like equipment conflict or lack of triangulation severely hampered the clinical application of this technology. The appearance of single-port laparoscopic flexible instruments makes up for those deficiencies to a great extent. The element is to add a wrist joint to the tip of the instrument to form triangulation and reduce equipment conflict. But this technique is still in an early stage of development. The purpose of this article is to summarize the characteristics and problems of existing flexible single-port laparoscopic instruments, and to provide information for the further improvement, finally the future development was expected.