Risk factor analysis of conversion in laparoscopic liver resection for intrahepatic cholangiocarcinoma.

BACKGROUND: The risk factors of patients with intrahepatic cholangiocarcinoma (ICC) requiring conversion to open surgery have not been adequately studied. This study aimed to determine the risk factors and postoperative outcomes of conversion in patients with ICC. METHODS: From May 2014 to September 2022, Unplanned conversions were compared with successful LLRs. RESULTS: 153 patients with ICC initially underwent LLR, of which 41 (26.8%) required conversion to open surgery. Multivariate analysis for those factors that were statistically significant or confirmed by clinical studies, tumor proximity to the major vessels (OR 6.643, P < 0.001), and previous upper abdominal surgery (OR 3.140, P = 0.040) were independent predictors of unplanned conversions. Compared to successful LLRs, unplanned conversions showed longer operative times (300.0 vs. 225.0 min, P < 0.001), more blood loss (500.0 vs. 200.0 mL, P < 0.001), higher transfusion rates (46.3% vs. 11.6%, P < 0.001), longer length of stays (13.0 vs. 8.0 days, P < 0.001), and higher rates of major morbidity (39.0% vs. 11.6%, P < 0.001). However, there was no statistically significant difference in 30-day or 90-day mortality between the conversion group and the laparoscopic group. CONCLUSION: Conversion during LLR should be anticipated in ICC patients with prior upper abdominal surgery or tumor proximity to major vessels as features.

Peripheral blood circular RNA circ-0008102 may serve as a novel clinical biomarker in beta-thalassemia patients.

Circular RNA circ-0008102 has previously been found dysregulated in ß-thalassemia (ß-thal) in circRNAs microarray (GSE196682 and GSE241141). Our study is aimed at identifying whether circ-0008102 could be a novel biomarker in ß-thal. The peripheral blood of pediatric ß-thal patients with (n = 39) or without (n = 20) blood transfusion and healthy controls (n = 30) was selected. qRT-PCR, ROC curve analysis, Spearman correlation analysis, and FISH were used to analyze clinical value of circ-0008102. qRT-PCR confirmed that circ-0008102 expression in pediatric ß-thal patients without blood transfusion was significantly higher. ROC curves analysis showed that the AUC of circ-0008102 for differentiating patients without blood transfusion from patients with blood transfusion and healthy controls with an AUC of 0.733 and 0.711. Furthermore, circ-0008102 expression was positively correlated with the levels of RBC, HbF, ß-globin, and γ-globin mRNA, but was negatively corrected with the levels of HbA and Cr. circ-0008102 was mainly located in the cytoplasm. circ-0008102 could induce the activation of γ-globin and negatively regulate the expression of the five highest-ranking candidate miRNAs (miR-372-3p, miR-329-5p, miR-198, miR-152-5p, and miR-627-3p) in K562 cells. CONCLUSION: We demonstrate that peripheral blood upregulated circ-0008102 may serve as a novel clinical biomarker for pediatric ß-thal without blood transfusion. WHAT IS KNOWN: • CircRNAs are known to be involved in various human diseases, and several circRNAs are regarded as a class of promising blood-based biomarkers for detection of ß-thal. • CircRNAs exert biological functions by epigenetic modification and gene expression regulation, and dysregulated circRNAs in ß-thal might be involved in the induction of HbF in ß-thal. WHAT IS NEW: • Peripheral blood circ-0008102 maybe serve as a novel clinical biomarker for detection of pediatric ß-thal without blood transfusion. • Circ-0008102 participates in the pathogenesis of ß-thal through regulating γ-globin expression, and negatively regulates the expression of miR-372-3p, miR-329-5p, miR-198, miR-152-5p and miR-627-3p.

Local treatment benefits patients with oligometastatic prostate cancer: A systematic review and meta-analysis.

OBJECTIVES: This study aims to evaluate the efficacy of local treatment (LT), including radiotherapy (RT) and cytoreductive prostatectomy (CRP), in improving outcomes for patients with oligometastatic prostate cancer (OmPCa). METHODS: A systematic review and meta-analysis of articles from PubMed, Embase, and Web of Science published between 2010 and November 2023 were conducted. The study included 11 articles, comprising three randomized controlled trials (RCTs) and eight retrospective analyses. The study assessed overall survival (OS), radiographic progression-free survival (rPFS), prostate-specific antigen (PSA) PFS, cancer-specific survival (CSS), and complication rate (CR). RESULTS: OS was significantly improved in the LT group, with both RCTs and non-RCTs showing statistical significance [hazard ratios (HR) = 0.64; 95% confidence intervals (95% CIs), 0.51-0.80; p < 0.0001; HR = 0.55; 95% CIs, 0.40-0.77; p = 0.0004]. For rPFS, RCTs did not show statistically significant outcomes (HR = 0.60; 95% CIs, 0.34-1.07; p = 0.09), whereas non-RCTs demonstrated significant results (HR = 0.42; 95% CIs, 0.24-0.72; p = 0.002). Both RCTs and non-RCTs showed a significant improvement in PSA-PFS (HR = 0.44; 95%CI, 0.29-0.67; p = 0.0001; HR = 0.51; 95% CIs, 0.32-0.81; p = 0.004). For CSS, RCTs demonstrated statistical differences (HR = 0.65; 95% CIs, 0.47-0.90; p = 0.009), whereas non-RCTs did not (HR = 0.61; 95% CIs, 0.29-1.27; p = 0.19). Regarding CR, the risk difference was -0.22 (95% CIs, -0.32 to -0.12; p < 0.00001). CONCLUSION: LT significantly improved OS and PFS in patients with OmPCa. Further RCTs are necessary to confirm these results.

First Report of Filipino ß0-Thalassemia/ß-Thalassemia in a Chinese Family.

A pregnant woman living in Fujian Province, southeastern China, presented due to a risk of having a baby with ß-thalassemia major, during her second pregnancy, since she and her husband were suspected as ß-thalassemia carriers and their affected daughter was a transfusion-dependent patient. Using the common α-thalassemia and ß-thalassemia genotypes test, the pregnant woman was diagnosed as a ß-thalassemia carrier with ßIVS-2 - 654 (C→T)/ßN genotype and her daughter had a homozygosity for IVS - 2 - 654 (C→T) mutation, however, no abnormalities were detected in her husband. SMRT identified a Filipino ß0-deletion in her husband, and MLPA also revealed an unknown deletion in the HBB gene. Electrophoresis showed approximately 350 bp of the PCR product, and the ß-Filipino genotype presented novel fracture fragments ranging from 5,112,884 to 5,231,358 bp, and lacked a 118,475 bp fragment relative to the wild-type sequence. The daughter was therefore diagnosed with the ßIVS-2 - 654 (C→T)/ßFilipino genotype. Prenatal diagnosis with umbilical cord blood at 27th week of gestation showed heteroztgosity for IVS - 2 - 654 (C→T) mutation in the fetus and continued pregnancy was recommended. In conclusion, we identified the Filipino ß0-deletion in a Chinese family, from Fujian area, for the first time, during prenatal screening.

Safety and feasibility of laparoscopic liver resection for intrahepatic cholangiocarcinoma: a propensity score-matched study.

BACKGROUND: Laparoscopic liver resection (LLR) is controversial in treating intrahepatic cholangiocarcinoma (ICC). Therefore, this study aimed to evaluate the safety and feasibility of LLR for the treatment of ICC and explored the independent factors affecting the long-term prognosis of ICC. METHODS: We included 170 patients undergoing hepatectomy for ICC from December 2010 to December 2021 and divided them into LLR group and open liver resection (OLR) group. We used propensity score matching (PSM) analysis to reduce the impact of data bias and confounding variables and then compared the short-term and long-term prognosis of LLR and OLR in treating ICC; Cox proportional hazards regression model was adopted to explore the independent factors affecting the long-term prognosis of ICC. RESULTS: A total of 105 patients (70 in the LLR group and 35 in the OLR group) were included after 2:1 PSM analysis. There was no difference in demographic characteristics and preoperative indexes between the two groups. The perioperative results of the OLR group were worse than those of the LLR group, that is, the intraoperative blood transfusion rate (24 (68.6) vs 21 (30.0)), blood loss (500 (200-1500) vs 200 (100-525)), and the morbidity of major postoperative complications (9 (25.7) vs 6 (8.5)) in the OLR group were worse than those in LLR group. LLR could enable patients to obtain an equivalent long-term prognosis compared to OLR. The Cox proportional hazards regression model exhibited that no matter before or after PSM, preoperative serum CA12-5 and postoperative hospital stay were independent factors affecting overall survival, while only lymph node metastasis independently influenced recurrence-free survival. CONCLUSIONS: Compared with ICC treated by OLR, the LLR group obtained superior perioperative period outcomes. In the long run, LLR could enable ICC patients to receive an equivalent long-term prognosis compared to OLR. In addition, ICC patients with preoperative abnormal CA12-5, lymph node metastasis, and more extended postoperative hospital stay might suffer from a worse long-term prognosis. However, these conclusions still need multicenter extensive sample prospective research to demonstrate.

Laparoscopic Orthotopic Right Hemihepatectomy by Anterior Approach Combined with Inferior Vena Cava Thrombectomy.

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly aggressive malignant disease with a high rate of vascular invasion. (Bruix et al. in Gastroenterology 150:835-853, 2016; Xia et al. in Oncol Lett 20:101, 2020) The conventional surgical strategy for HCC with inferior vena cava (IVC) tumor thrombus is open major surgery with cardiopulmonary bypass, combined with large trauma. (Liu et al. in Eur J Gastroenterol Hepatol 24:186-194, 2012; Bai et al. in J Oncol 2020:3264079, 2020) We report a video of laparoscopic hemihepatectomy and thrombectomy without bypass. As far as we are aware, this is the first report on IVC thrombectomy using a minimally invasive surgical technique. PATIENT: A 52-year-old male was admitted to our institution for a giant hepatic mass in the right liver combined with IVC tumor thrombosis. After 2 months of preoperative systemic treatment, the tumor had reduced to 8 cm and the enhancement of tumor thrombosis in the magnetic resonance imaging (MRI) scan was significantly reduced. METHODS: We used laparoscopy combined with thoracoscopy to perform the surgery, with the patient placed in the supine position. The abdominal trocar position is shown in Fig. 1b. First, we set the blocking band of the suprahepatic IVC in the thoracoscopy. Infrahepatic IVC occlusion and the Pringle maneuver device were prepared for laparoscopy. After fully exposing the retrohepatic IVC, we performed a thrombectomy and IVC suture completely in laparoscopy. Finally, the patient was transferred to the intensive care unit (ICU) for observation. Fig. 1 a Three-dimensional reconstruction model of the patient (a giant hepatic mass and tumor thrombosis extending to the suprahepatic IVC). b Trocar position for the laparoscopic surgery. The patient was placed in the supine position, and the 5, 6, and 7 intercostal axillary fronts were set for the thoracoscopic trocar, while the remaining five abdominal trocars were set for laparoscopic operation. c Retrohepatic IVC before being cut open. The fullness indicates the position of the tumor thrombosis. d Thrombectomy and suture of the IVC. IVC inferior vena cava, TT tumor thrombus RESULTS: Operation time was 495 mins and estimated blood loss was 1000 mL. The patient was discharged on the thirteenth day after the surgery. HCC was confirmed in histopathology. CONCLUSION: Laparoscopic hepatectomy with IVC thrombectomy is a possible operation for HCC combined with IVC tumor thrombus, offering hope for minimally invasive treatment of such cases; however, it is still a highly challenging procedure.

Efficacy of laparoscopic repeat hepatectomy compared with open repeat hepatectomy: a single-center, propensity score matching study.

INTRODUCTION: Laparoscopic repeat hepatectomy (LRH) is considered to be a technically challenging procedure which has not been widely applied. This study aimed to assess the accessibility and security of LRH for patients with hepatic tumor recurrence. METHODS: Between January 2010 and October 2020, we performed 48 LRHs and 31 open repeat hepatectomies (ORHs) for recurrent liver cancer. LRHs were matched to ORHs (1:1) using propensity score matching (PSM) created by comparing preoperative factors. The perioperative data of patients were retrospectively analyzed, including baseline data, operative time, intraoperative blood loss, pathology, days of postoperative stay, complication morbidity, and mortality within 30 days. Overall survival and recurrence-free survival rates with appropriate follow-up were obtained to evaluate the long-term outcomes. RESULTS: Compared with the ORH, LRH was related with shorter operative duration (169.9 versus 232.9 ml, p < 0.01), less intraoperative bleeding (100.0 versus 500.0 ml, p < 0.01), lower rate of blood transfusion (8.3% versus 58.1%, p < 0.01), and shorter hospitalization (5.0 versus 11.0 days, p < 0.01). The median follow-up was 31 months. The LRH 1-, 3-, and 5-year overall survival were 77.1%, 61.6%, and 46.2% versus 82.3%, 66.5%, and 29.5% for ORH (p = 0.77). The 1-, 3-, and 5-year disease-free survival rates of the two groups were 73.4%, 62.0%, and 44.3% versus 66.1%, 44.1%, and 14.7%, respectively (p = 0.22). CONCLUSIONS: Laparoscopic repeated hepatectomy is safe and practicable with great short-term results for selected patients.

Safety and feasibility of laparoscopic liver resection for hepatocellular carcinoma with clinically significant portal hypertension: a propensity score-matched study.

BACKGROUND: The presence of clinically significant portal hypertension (CSPH) remains a relative contraindication to liver resection for patients with resectable hepatocellular carcinoma (HCC). The goal of this study was to explore whether a laparoscopic approach could extend the indications for hepatectomy to patients with PH. METHOD: Patients who underwent laparoscopic liver resection (LLR) from February 2016 to September 2019 performed by a single medical team were included in this study. We analyzed the surgical and oncological outcomes between groups with and without CSPH before and after propensity score matching (PSM). RESULT: We enrolled 156 patients divided into two groups according to the presence (CSPH, n = 26) or absence (non-CSPH, n = 130) of CSPH. CSPH group was associated with more clinical signs of liver dysfunction (p < 0.05). After PSM (n = 48 patients), the CSPH group tended to have a longer postoperative hospital stay (p = 0.054); however, there was no difference in operation time (p = 0.329), blood loss volume (p = 0.392), transfusion rates (p = 0.701), rate of conversion to open surgery (p = 0.666), surgical margin (p = 0.306), surgical mortality (n = 0), or comprehensive complication index (p = 0.844) between the two groups. The median follow-up time for the entire cohort was 19.6 months (range 0.2-40.6 months). The 3-year overall survival rate was 62.9% in the CSPH group and 84.3% in the non-CSPH group (p = 0.1090), and results were similar after PSM (p = 0.5734). CONCLUSIONS: LLR is safe and feasible for HCC with PH. The introduction of minimally invasive surgery, represented by LLR, can appropriately expand the indications for hepatectomy.

Safety and effectiveness evaluation of a two-handed technique combining harmonic scalpel and laparoscopic Peng's multifunction operative dissector in laparoscopic hemihepatectomy.

OBJECTIVES: This study was designed to evaluate the safety and effectiveness of a two-hand technique combining harmonic scalpel (HS) and laparoscopic Peng's multifunction operative dissector (LPMOD) in patients who underwent laparoscopic hemihepatectomy (LHH). METHODS: We designed and conducted a case-control study nested in a prospectively collected laparoscopic liver surgery database. Patients who underwent LHH for liver parenchyma transection using HS + LPMOD were defined as cases (n = 98) and LPMOD only as controls (n = 47) from January 2016 to May 2018. Propensity score matching (1:1) between the case and control groups was used in the analyses. RESULTS: The case group had significantly less intraoperative blood loss in milliliters (169.4 ± 133.5 vs. 221.5 ± 176.3, P = 0.03) and shorter operative time in minutes (210.5 ± 56.1 vs. 265.7 ± 67.1, P = 0.02) comparing to the control group. The conversion to laparotomy, postoperative hospital stay, resection margin, the mean peak level of postoperative liver function parameters, bile leakage rate, and others were comparable between the two groups. There was no perioperative mortality. CONCLUSIONS: We demonstrated that the two-handed technique combing HS and LPMOD in LHH is safe and effective which is associated with shorter operative time and less intraoperative blood loss compared with LPMOD alone. The technique facilitates laparoscopic liver resection and is recommended for use.

Differentiation and management of hepatobiliary mucinous cystic neoplasms: a single centre experience for 8 years.

BACKGROUND: Hepatobiliary mucinous cystic neoplasms (H-MCNs) are relatively rare cystic neoplasms in the liver. The differential diagnosis of H-MCNs remains big challenging, and the management and prognosis between the hepatic simple cyst (HSC) and H-MCNs are quite different. This study aimed to present our experience in the management of H-MCNs and provide a preoperative H-MCNs risk prediction nomogram to differentiating H-MCNs from liver cystic lesions. METHODS: 29 patients diagnosed with H-MCNs and 75 patients diagnosed with HSC between June 2011 and June 2019 at Zhejiang University School of medicine, Sir Run-Run Shaw Hospital were reviewed in this study. We analyzed the demographic and clinicopathological variables. RESULTS: US, CT, and MRI could accurately diagnose only 3.4%, 46.1%, and 57.1% of H-MCNs, respectively. After univariate analysis and multivariate logistic regression analysis, the variables significantly associated with H-MCNs were enhancement after contrast (p = 0.009), tumour located in the left lobe (p = 0.02) and biliary ductal dilation (p = 0.027). An H-MCNs risk predictive nomogram was constructed, which showed excellent discrimination (areas under the receiver operating characteristic curve were 0.940) and consistent calibration between the predicted probability and actual probability. CONCLUSION: Among patients with H-MCNs, the location of the tumour, enhancement in CT scan, and biliary duct dilation are significantly independent risk factors. The appropriate treatment of H-MCNs is radical resection. Using our Nomogram could facilitate screening and identification of patients with liver cystic lesions.

Laparoscopic anatomical portal territory hepatectomy using Glissonean pedicle approach (Takasaki approach) with indocyanine green fluorescence negative staining: how I do it.

BACKGROUND: Laparoscopic anatomical resection (LAR) is a highly challenging procedure. This study aimed to describe our experience of the LAR with an indocyanine green fluorescence negative staining (ICGNS) by the Glissonean pedicle transection (Takasaki) approach. METHODS: From April 2017 to December 2019, 43 consecutive patients underwent LAR with ICGNS strategy in our medical team. The details of the ICGNS strategy were described. The demographic and clinicopathological data of the included patients were retrospectively analyzed. RESULTS: The extent of resections included right hemihepatectomy (n = 12), left hemihepatectom (n = 4), left lateral sectionectomy (n = 3), Right anterior sectionectomy (n = 3), Right posterior sectionectomy (n = 6), central hepatectomy (n = 2), single anterolateral segmentectomy (n = 5), single posterosuperior segmentectomy (n = 6), and bisegmentectomy (n = 2). The mean operation time was 212 ± 53 min, and the median estimated blood loss was 200 (100-300) ml. The overall complication rate was 30.2% (grade I, 14%; grade II, 14%; grade III, 2.3%). The median duration of postoperative hospital stay was 6 (4-7) days. CONCLUSION: ICGNS is a safe and feasible LAR strategy that greatly facilitates selecting the liver transection plane, although its benefits need to be verified by large-sample comparative studies.

Laparoscopic repeat hepatectomy for treating recurrent liver cancer.

BACKGROUND: Laparoscopic repeat hepatectomy (LRH) is a technically challenging procedure, so LRH for recurrent liver cancer has not been widely accepted. The aim of this study was to perform a systematic review of the current literature to identify and evaluate available data of LRH for recurrent hepatocellular carcinoma (rHCC) and metastases tumour of liver, especially of colorectal liver metastases (CRLM), focusing on the safety and feasibility. METHODS: A comprehensive search of the PubMed database was performed for all studies published in English evaluating LRH for rHCC and recurrent metastases tumour of liver from 1st January, 2005 to 1st June, 2019. RESULTS: A total of 15 studies which comprised 444 patients and reported outcomes for the efficacy and safety of LRH in the treatment of rHCC or CRLM were included in the present review. Moreover, nine studies compared the perioperative outcomes of LRH versus open repeat hepatectomy (ORH). LRH was superior to ORH with reduced blood loss, shorter operative time, shorter hospital stay and lower morbidity rates. CONCLUSIONS: LRH can safely performed in rHCC or CRLM patients with cirrhosis, previous open hepatectomy, multiple recurrent lesions and tumours located in difficult posterosuperior segments.

N6-methyladenosine-modified CircRNA-SORE sustains sorafenib resistance in hepatocellular carcinoma by regulating ß-catenin signaling.

BACKGROUND AND AIMS: Accumulating evidence suggests that the primary and acquired resistance of hepatocellular carcinoma (HCC) to sorafenib is mediated by multiple molecular, cellular, and microenvironmental mechanisms. Understanding these mechanisms will enhance the likelihood of effective sorafenib therapy. METHODS: In vitro and in vivo experiments were performed and clinical samples and online databases were acquired for clinical investigation. RESULTS: In this study, we found that a circular RNA, circRNA-SORE, which is up-regulated in sorafenib-resistant HCC cells, was necessary for the maintenance of sorafenib resistance, and that silencing circRNA-SORE substantially increased the efficacy of sorafenib-induced apoptosis. Mechanistic studies determined that circRNA-SORE sequestered miR-103a-2-5p and miR-660-3p by acting as a microRNA sponge, thereby competitively activating the Wnt/ß-catenin pathway and inducing sorafenib resistance. The increased level of circRNA-SORE in sorafenib-resistant cells resulted from increased RNA stability. This was caused by an increased level of N6-methyladenosine (m6A) at a specific adenosine in circRNA-SORE. In vivo delivery of circRNA-SORE interfering RNA by local short hairpin RNA lentivirus injection substantially enhanced sorafenib efficacy in animal models. CONCLUSIONS: This work indicates a novel mechanism for maintaining sorafenib resistance and is a proof-of-concept study for targeting circRNA-SORE in sorafenib-treated HCC patients as a novel pharmaceutical intervention for advanced HCC.

Laparoscopic Anatomical Portal Territory Hepatectomy with Cirrhosis by Takasaki's Approach and Indocyanine Green Fluorescence Navigation (with Video).

BACKGROUND: Anatomical liver resection has shown advantages in the treatment of hepatocellular carcinoma (HCC).1 Pure laparoscopic hepatectomy for some deep lesions remains challenging, especially for anatomical resection.2 Because of many kinds of hepatic venous variations, resection along the hepatic vein may not be a "real" anatomical resection. We used a three-dimensional visualization technique to construct a portal territory model which represented the patient-specific anatomy. During the operation, the territory was visualized by indocyanine green (ICG) navigation. PATIENT: A 48-year-old man was admitted to our institution with a single hepatic mass of 4.5 cm in segment 7. The patient suffered hepatitis B related cirrhosis and portal hypertension. METHODS: A resection plan was put forward by 3-D visualization technique in advance (Fig. 1a). The patient was placed in a supine position with pillows underneath the upper right semi-lateral body. The position of the trocar is shown in Fig. 1b. After removal of the gallbladder and overhang of the G6, the G7 was dissected and ligated by Takasaki's Glissonean pedicle approach (Fig. 1c).3 The ischemic line appeared and was consistent with the demarcation line of portal territory (Fig. 1d). A parenchyma transection was performed along the boundary of the unstained side of the ICG fluorescence. Fig. 1 Some important images from the video. a The trocar position of this laparoscopic surgery. Operator-1 or -2: the first and the second trocar for the operator; assistant: the trocar for the assistant; operator/assistant: the trocar can be used by operator and assistant interchangeably; scope: the trocar for the laparoscope. b The transection plan constructed by preoperative 3-D visualization technique. The blue area was the tumor-bearing portal territory and targeted part of the liver that should be removed. c The intrahepatic anterior and posterior Glissonean pedicle of G6 and G7. G6: glissonean pedicle of segment 6; G7: glissonean pedicle of segment 7. d The ischemic line, the demarcation line of portal territory staining by ICG and the target territory constructed by 3-D visualization technique before the operation RESULT: The operation time was 205 min, the estimated blood loss was 150 ml. With no postoperative complications, the patient was discharged on the fourth day. Hepatocellular carcinoma was confirmed in histopathology. The resection margin was free of tumor involvement. CONCLUSION: A preoperative 3-D visualization technique combined with intraoperative ICG fluorescence navigation could facilitate a precise and safe laparoscopic anatomical hepatectomy.

Correction to: Laparoscopic Anatomical Portal Territory Hepatectomy with Cirrhosis by Takasaki's Approach and Indocyanine Green Fluorescence Navigation (with Video).

In the original version of the article all of the authors' first and last names were transposed. The original article has been updated.

A novel simple intra-corporeal Pringle maneuver for laparoscopic hemihepatectomy: how we do it.

INTRODUCTION: To prevent and control hemorrhage is the key to successfully perform laparoscopic hemihepatectomy (LHH). Pringle's maneuver (PM) is the standard hepatic inflow occlusion technique. Our study was to describe a novel simple way to perform totally intra-corporeal laparoscopic PM and to explore the feasibility of combining PM and selective hemihepatic vascular occlusion technique in LHH. METHODS: We extracted and analyzed the data of patients who consecutively underwent LHH to validate this new surgery technique. Between January, 2016 and December, 2017, 34 patients were included. Data of pre-operation, operation and post-operation were collected, including some demographic data, operative time, operative blood loss, transfusion rate, hepatic hilum occlusion rate and time, pathologic results, short-term complication, and postoperative hospitalization days. RESULTS: Only one patient (3.0%) in our series required conversion to laparotomy as a result of the severe adhesion. The average operative time was 216.9 ± 60.3 min. The mean hepatic inflow occlusion time was 25.3 ± 14.5 min. The average estimated blood loss was 192.9 ± 152.2 ml. All patients received R0 resection. CONCLUSION: The novel hepatic inflow occlusion device is a safe reliable and convenient technique for LHH that is associated with favorable perioperative outcomes and low risk of conversion.

DOA Estimation Using Fourth-Order Cumulants in Nested Arrays with Structured Imperfections.

Recently developed super nested array families have drawn much attention owing to their merits on keeping the benefits of the standard nested arrays while further mitigating coupling in dense subarray portions. In this communication, a new mutual coupling model for nested arrays is constructed. Analyzing the structure of the newly formed mutual coupling matrix, a transformation of the distorted steering vector to separate angular information from the mutual coupling coefficients is revealed. By this property, direction of arrival (DOA) estimates can be determined via a grid search for the minimum of a determinant function of DOA, which is induced by the rank reduction property. We also extend the robust DOA estimation method to accommodate the unknown mutual coupling and gain-phase mismatches in the nested array. Compared with the schemes of super nested array families on reducing the mutual coupling effects, the solutions presented in this paper has two advantages: (a) It is applicable to the standard nested arrays without rearranging the configuration to increase the inter-element spacing, alleviating the cross talk in dense uniform linear arrays (ULAs) as well as gain-phase errors in sparse ULA parts; (b) Perturbations in nested arrays are estimated in colored noise, which is significant but rarely discussed before. Simulations results corroborate the superiority of the proposed methods using fourth-order cumulants.

Cumulant-based DOA Estimation of Noncircular Signals Against Unknown Mutual Coupling.

To effectively find the direction of non-circular signals received by a uniform linear array (ULA) in the presence of non-negligible perturbations between array elements, i.e., mutual coupling, in colored noise, a direction of arrival (DOA) estimation approach in the context of high order statistics is proposed in this correspondence. Exploiting the non-circularity hidden behind a certain class of wireless communication signals to build up an augmented cumulant matrix, and carrying out a reformulation of the distorted steering vector to extract the angular information from the unknown mutual coupling, by exploiting the characteristic of mutual coupling, i.e., a limited operating range and an inverse relation of coupling effects to interspace, we develop a MUSIC-like estimator based on the rank-reduction (RARE) technique to directly determine directions of incident signals without mutual coupling compensation. Besides, we provide a solution to the problem of coherency between signals and mutual coupling between sensors co-existing, by selecting a middle sub-array to mitigate the undesirable effects and exploiting the rotation-invariant property to blindly separate the coherent signals into different groups to enhance the degrees of freedom. Compared with the existing robust DOA methods to the unknown mutual coupling under the framework of fourth-order cumulants (FOC), our work takes advantage of the larger virtual array and is able to resolve more signals due to greater degrees of freedom. Additionally, as the effective aperture is virtually extended, the developed estimator can achieve better performance under scenarios with high degree of mutual coupling between two sensors. Simulation results demonstrate the validity and efficiency of the proposed method.

Organoborane catalyzed regioselective 1,4-hydroboration of pyridines.

A bulky organoborane Ar(F)2BMe (Ar(F) = 2,4,6-tris(trifluoromethyl)phenyl, 1) has been synthesized. In C6D6 solution this organoborane and pyridine form a frustrated Lewis pair. Under mild conditions, 1 can efficiently catalyze 1,4-hydroboration of a series of pyridines. This reaction is highly chemo- and regioselective. The reaction intermediate, a boronium complex [Py2Bpin][Ar(F)2B(H)Me] (3), was characterized in solution by NMR spectroscopy, which was also confirmed by DFT calculation.