Primary hepatic chronic expanding hematoma: a case report and literature review

Chronic expanding hematoma (CEH), first reported in 1968, is a hematoma that gradually enlarges over a long course of time after an initial period of bleeding. It can occur anywhere in the body; however, there are many reports of its occurrence in the thoracic cavity. Primary hepatic CEH is extremely rare. In this current study, we report on a case of primary hepatic CEH diagnosed preoperatively, with a review of the literature. A 68-year-old man presented with liver dysfunction. Abdominal computed tomography revealed a giant cystic tumor in the left lobe of the liver, with a longer axis of approximately 12 cm. Magnetic resonance imaging revealed a mosaic pattern with a mixture of high and low signals within the tumor on T1-weighted images and a high signal at the tumor margin on T2-weighted images. Based on these findings, primary hepatic CEH was suspected. However, other malignant tumors could not be excluded owing to tumor compression resulting in bile duct dilatation. Left trisectionectomy was performed, followed by bile duct drainage and percutaneous transhepatic portal vein embolization. Intraoperative hemorrhage was controlled by the Pringle maneuver and with temporary clamping of the inferior vena cava. Pathological examination revealed a pseudocyst containing a clot, consistent with CEH. In conclusions, the case report illustrates the potential to enhance preoperative diagnosis, inform surgical approaches, and minimize associated risks. Furthermore, it highlights the importance of increasing awareness and research on this condition for improved clinical decision-making and patient care.

A Standardized Interrupted Parachute Suture Technique in Hepaticojejunostomy for Patients With Perihilar Cholangiocarcinoma

BACKGROUND/AIM

Although hepaticojejunostomy is a relatively uncomplicated surgical procedure, its postoperative complications can range from a prolonged hospital stay to death. In hepatectomy, including resection of the perihilar bile duct for perihilar cholangiocarcinoma, the difficulty of performing hepaticojejunostomy and the complication rate increase due to the characteristics of surgery required for perihilar cholangiocarcinoma. In this study, we standardized the interrupted parachute suture technique and examined its safety and efficacy.

PATIENTS AND METHODS

The greatest advantage of our technique is the use of interrupted sutures, and the anterior bile duct is threaded prior to completing the posterior anastomosis. Therefore, the field of vision is better when threading the bile duct and intestinal tract, and the needle handling procedure can be performed relatively stress-free regardless of the type of hepatectomy.

RESULTS

In patients who underwent hepaticojejunostomy, postoperative biliary complications, such as anastomotic leakage, biliary stricture, hemobilia, and jejunal bleeding, were not observed.

CONCLUSION

The interrupted suture is easy to implement in biliary reconstruction and can facilitate any type of hepatic resection. In addition, the standardized technique was efficient and safe and did not increase the incidence of postoperative complications.

The Japanese Breast Cancer Society Clinical Practice Guidelines for surgical treatment of breast cancer, 2022 edition

The 2022 revision of the Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines for surgical treatment of breast cancer was updated following a systematic review of the literature using the Medical Information Network Distribution Service (MINDS) procedure, which focuses on the balance of benefits and harms for various clinical questions (CQs). Experts in surgery designated by the JBCS addressed five areas: breast surgery, axillary surgery, breast reconstruction, surgical treatment for recurrent and metastatic breast cancer, and other related topics. The revision of the guidelines encompassed 4 CQs, 7 background questions (BQs), and 14 future research questions (FRQs). A significant revision in the 2022 edition pertained to axillary management after neoadjuvant chemotherapy in CQ2. The primary aim of the 2022 JBCS Clinical Practice Guidelines is to provide evidence-based recommendations to empower patients and healthcare professionals in making informed decisions regarding surgical treatment for breast cancer.

The importance of laparoscopic surgery for young urologists remains unwavering even in the era of robot-assisted surgery

Robot-assisted surgery (RAS) cannot be achieved without the performance of laparoscopic surgical techniques by a patient-side surgeon (PSS). In many medical institutions in Japan, young urologists often take on the role of a PSS. Participating in RAS as a PSS provides a good opportunity to acquire not only the knowledge necessary for surgery, but also skills in laparoscopic surgical techniques. Learning laparoscopic surgery as a PSS may contribute to improving the quality of RAS. Furthermore, it will lead to skill improvement as an operator in laparoscopic surgery. However, notably, opportunities for young urologists to perform laparoscopic surgery are decreasing in the current era of RAS. Under these circumstances, we believe that cadaver surgical training will become increasingly important in the future. We believe that performance of cadaver surgical training will contribute to increased motivation, enhance the understanding of surgical procedures, and facilitate the acquisition of surgical techniques.

Sall1 and Sall4 cooperatively interact with Myocd and SRF to promote cardiomyocyte proliferation by regulating CDK and cyclin genes

Sall1 and Sall4 (Sall1/4), zinc-finger transcription factors, are expressed in the progenitors of the second heart field (SHF) and in cardiomyocytes during the early stages of mouse development. To understand the function of Sall1/4 in heart development, we generated heart-specific Sall1/4 functionally inhibited mice by forced expression of the truncated form of Sall4 (ΔSall4) in the heart. The ΔSall4-overexpression mice exhibited a hypoplastic right ventricle and outflow tract, both of which were derived from the SHF, and a thinner ventricular wall. We found that the numbers of proliferative SHF progenitors and cardiomyocytes were reduced in ΔSall4-overexpression mice. RNA-sequencing data showed that Sall1/4 act upstream of the cyclin-dependent kinase (CDK) and cyclin genes, and of key transcription factor genes for the development of compact cardiomyocytes, including myocardin (Myocd) and serum response factor (Srf). In addition, ChIP-sequencing and co-immunoprecipitation analyses revealed that Sall4 and Myocd form a transcriptional complex with SRF, and directly bind to the upstream regulatory regions of the CDK and cyclin genes (Cdk1 and Ccnb1). These results suggest that Sall1/4 are critical for the proliferation of cardiac cells via regulation of CDK and cyclin genes that interact with Myocd and SRF.

Efficacy of CT Value Along Portal Vein for Preoperative Prediction of Portal Vein Resection in Pancreatic Head Cancer

BACKGROUND

It is important for surgeons to determine whether combined portal vein (PV) resection (PVR) is necessary before surgery. The present study aimed to determine the ability of computed tomography (CT) value along the PV in predicting the necessity for concomitant PVR.

METHODS

A total of 107 consecutive patients who underwent pancreaticoduodenectomy (PD) for invasive ductal carcinoma of the pancreatic head at our institute between September 2007 and September 2020 were reviewed retrospectively. Univariate analysis to predict PVR was performed with preoperative radiological valuables acquired by Synapse Vincent. The resected specimen near the PV or the PV notch was analyzed by histopathological findings.

RESULTS

Only the CT value of the PV was independently associated with PVR (Mann-Whitney U test; P = .045, logistic regression test; P = .039). The outer boundary of the PV was unclear in the cases without pathological PV invasion and PVR due to the development of smooth muscle in the outer membrane of the PV and the proliferation of collagen fibers. The elastic fibers were arranged regularly in the notch portion of the PV in cases wherein PVR was not performed.

DISCUSSION

The CT value along the PV was independently associated with PVR and is the only predictor of PVR. These results were very useful in predicting PVR preoperatively and were histopathologically supportive.

Early Identification of Patients with Potential Failure of Nonoperative Management for Gastroduodenal Peptic Ulcer Perforation

INTRODUCTION

We aimed to identify objective factors associated with failure of nonoperative management (NOM) of gastroduodenal peptic ulcer perforation (GDUP) and establish a scoring model for early identification of patients in whom NOM of GDUP may fail.

METHODS

A total of 71 patients with GDUP were divided into NOM (cases of NOM success) and operation groups (cases requiring emergency operation or conversion from NOM to operation). Using logistic regression analysis, a scoring model was established based on the independent factors. The patients were stratified into low-risk and high-risk groups according to the scores.

RESULTS

Of the 71 patients, 18 and 53 were in the NOM and operation groups, respectively. Ascites in the pelvic cavity on computed tomography (CT) and sequential organ failure assessment (SOFA) score at admission were identified as independent factors for NOM failure. The scoring model was established based on the presence of ascites in the pelvic cavity on CT and SOFA score ≥2 at admission. The operation rates for GDUP were 28.6% and 86.0% in the low-risk (score, 0) and high-risk groups (scores, 2 and 4), respectively.

CONCLUSION

Our scoring model may help determine NOM failure or success in patients with GDUP and make decisions regarding initial treatment.

Preoperative scoring system for prediction of extended resection during emergency surgery for acute appendicitis

PURPOSE

Appendicectomy is the primary treatment for acute appendicitis. However, extended resection (ER) may be required in difficult cases. Preoperative prediction of ER may identify challenging cases but remains difficult. We aimed to establish a preoperative scoring system for ER prediction during emergency surgery for acute appendicitis.

METHODS

This was a single-center retrospective study. Patients who underwent emergency surgery for acute appendicitis between January 2014 and December 2022 were included and divided into ER and appendicectomy groups. Independent variables associated with ER were identified using multivariate logistic regression analysis. A new scoring system was established based on these independent variables. The discrimination of the new scoring system was assessed using the area under the receiver operating characteristic curve (AUC). The risk categorization of the scoring system was also analyzed.

RESULTS

Of the 179 patients in this study, 12 (6.7%) underwent ER. The time interval from symptom onset to surgery ≥ 4 days, a retrocecal or retrocolic appendix, and the presence of an abscess were identified as independent preoperative predictive factors for ER. The new scoring system was established based on these three variables, and the scores ranged from 0 to 6. The AUC of the scoring system was 0.877, and the rates of ER among patients in the low- (score, 0-2), medium- (score, 4), and high- (score, 6) risk groups were estimated to be 2.5%, 28.6%, and 80%, respectively.

CONCLUSION

Our scoring system may help surgeons identify patients with acute appendicitis requiring ER and facilitate decision-making regarding treatment options.

Altered actin dynamics is possibly implicated in the inhibition of mechanical stimulation-induced dermal fibroblast differentiation into myofibroblasts

The formation of hypertrophic scars and keloids is strongly associated with mechanical stimulation, and myofibroblasts are known to play a major role in abnormal scar formation. Wounds in patients with neurofibromatosis type 1 (NF1) become inconspicuous and lack the tendency to form abnormal scars. We hypothesized that there would be a unique response to mechanical stimulation and subsequent scar formation in NF1. To test this hypothesis, we investigated the molecular mechanisms of differentiation into myofibroblasts in NF1-derived fibroblasts and neurofibromin-depleted fibroblasts and examined actin dynamics, which is involved in fibroblast differentiation, with a focus on the pathway linking LIMK2/cofilin to actin dynamics. In normal fibroblasts, expression of α-smooth muscle actin (α-SMA), a marker of myofibroblasts, significantly increased after mechanical stimulation, whereas in NF1-derived and neurofibromin-depleted fibroblasts, α-SMA expression did not change. Phosphorylation of cofilin and subsequent actin polymerization did not increase in NF1-derived and neurofibromin-depleted fibroblasts after mechanical stimulation. Finally, in normal fibroblasts treated with Jasplakinolide, an actin stabilizer, α-SMA expression did not change after mechanical stimulation. Therefore, when neurofibromin was dysfunctional or depleted, subsequent actin polymerization did not occur in response to mechanical stimulation, which may have led to the unchanged expression of α-SMA. We believe this molecular pathway can be a potential therapeutic target for the treatment of abnormal scars.

The effects of continuous administration of diazepam on the recovery of lesion-induced nystagmus in unilaterally labyrinthectomised rats

BACKGROUND

Diazepam, a gamma-aminobutyric acid type A receptor agonist, is classified as a vestibular suppressant and is effective in treating acute vertigo. However, its effects on vestibular compensation (VC) remain unclear.

OBJECTIVES

We examined the effects of continuous administration of diazepam on the frequency of spontaneous nystagmus (SN) after unilateral labyrinthectomy (UL) as an index of the initial process of VC in rats.

MATERIALS AND METHODS

Diazepam was continuously administered at doses of 3.5 and 7.0 mg/kg/day, intraperitoneally, via an osmotic minipump. The frequency of SN beating against the lesion side after UL was measured. Potassium chloride (KCl) solution (1 M) was injected intratympanically to induce SN beating to the injection side.

RESULTS

Continuous administration of diazepam significantly and dose-dependently decreased the frequency of SN after UL, and also reduced the x intercept of the nonlinear regression curve of the decline in UL-induced SN with time in rats. However, the continuous administration of diazepam did not affect the frequency of intratympanic KCl-induced SN in the rats.

CONCLUSION

These findings suggested that continuous administration of diazepam accelerates the initial process of VC; however, it does not suppress the nystagmus-driving mechanisms in rats.

Reconstruction of a Spinal Accessory Nerve Defect Using Vascularized Vastus Lateralis Motor Nerve Graft

Massive resection of a malignant tumor of the head and neck region often requires loss of critical nerves, including the spinal accessory nerve. Recently, vascularized nerve grafts (VNGs) have been used to repair facial and other nerve defects with successful outcomes, even in cases involving factors that can inhibit nerve regeneration, such as radiotherapy. However, the effectiveness of these nerve grafts against postoperative radiotherapy has yet to be explored. We report the first successful case in reconstructing a spinal accessory nerve defect after total left parotidectomy with radical neck dissection, using a vascularized vastus lateralis motor nerve graft and an anterolateral thigh flap based on the lateral circumflex femoral system, with great shoulder function outcomes even after postoperative radiotherapy. A branch of vastus lateralis motor nerve perfused by the accompanying descending branch of lateral femoral circumflex vessel was used as a nerve graft, and was repaired in an end-to-end manner. The patient underwent postoperative radiotherapy to the area of operation. At 6-months follow-up, the patient was capable of 90 degrees lateral shoulder abduction, and at 18 months, achieved full-range shoulder abduction and reported neither functional limitations of the shoulder nor complaints of any shoulder pain (Disabilities of Arm, Shoulder, and Hand score 0). Although further study is necessary to fully understand the superiority of VNGs over postoperative radiotherapy, immediate nerve reconstruction using VNG for accessory nerve defects in patients scheduled for radiotherapy postoperation may be extremely beneficial for preserving shoulder motor function and sustaining the patient's quality of life.

Exposure of the hepatic vein trunk via tracing of its branches: a useful surgical procedure for laparoscopic anatomical hepatectomy

BACKGROUND

Although there are various advantages of laparoscopic liver resection (LLR) over open liver resection, some problems have been reported, such as disorientation and lack of control of bleeding during liver parenchymal dissection. In this study, we discuss a strategy to overcome the disorientation experienced during liver parenchymal dissection, especially in anatomical LLR.

TECHNICAL PRESENTATION

This procedure involves hepatic parenchymal dissection from the hepatic vein branch along its trunk to reveal an important landmark in anatomical LLR. Knowing which region of the liver is perfused into each hepatic vein in preoperative 3D simulation allows the tracing of the hepatic vein branch that naturally leads to the hepatic vein trunk. After that, hepatic resection can be easily completed by dissecting the line connected to the other landmarks, the Glisson branch, the root of the hepatic vein, and the liver demarcation line.

CONCLUSION

In conclusion, this surgical procedure that traces the branch of the hepatic vein exposes the trunk, which makes it a very useful tool for limited laparoscopic anatomical hepatectomy.

"Hydrogen-generating Si-based agent improves fat graft survival in rats"

BACKGROUND

Regulating excessive inflammation and oxidative stress in fat grafting may improve retention rates. Hydrogen effectively combats oxidative stress and inflammation and reportedly inhibits ischemia-reperfusion injury in various organs. Unfortunately, with conventional methods of hydrogen administration, incorporating hydrogen continuously into the body over a long period of time is difficult. We hypothesized that a Silicon (Si)-based agent we recently developed would aid in fat grafting as it can generate large amounts of hydrogen continuously in the body.

METHODS

Fat grafting was performed on the backs of rats fed either a normal or 1.0 wt% Si-based agent-containing diet. To investigate synergistic effects with adipose-derived stromal cells (ASCs), which improve retention rates of fat grafting, fat grafting with ASCs (1.0×10 5/400 mg fat) was also performed in each rat. Postoperative retention rates of grafted fat over time, inflammatory indices, apoptosis and oxidative stress markers, histological findings, and expression levels of inflammation-related cytokines and growth factors were compared between the four groups.

RESULTS

Intake of Si-based agent and addition of ASCs significantly reduced inflammatory indices, oxidative stress, and apoptosis of grafted fat, and improved long-term retention rates, histological parameters, and grafted fat quality. Under our experimental conditions, intake of the Si-based agent and addition of ASCs yielded comparable improvements in fat graft retention. Combining the two enhanced these effects even further.

CONCLUSION

Oral administration of the hydrogen-generating Si-based agent may improve grafted fat retention by regulating the inflammatory response and oxidative stress in grafted fat.

CLINICAL RELEVANCE STATEMENT

This study demonstrates improved grafted fat retention rates using a Si-based agent. This Si-based agent has the potential to expand the range of therapeutic indications of hydrogen-based therapy to conditions for which hydrogen has yet to be found effective, such as fat grafting.

Development of a scoring model based on objective factors to predict gangrenous/perforated appendicitis

BACKGROUND

The mortality rate of gangrenous/perforated appendicitis is higher than that of uncomplicated appendicitis. However, non-operative management of such patients is ineffective. This necessitates their careful exam at presentation to identify gangrenous/perforated appendicitis and aid surgical decision-making. Therefore, this study aimed to develop a new scoring model based on objective findings to predict gangrenous/perforated appendicitis in adults.

METHODS

We retrospectively analyzed 151 patients with acute appendicitis who underwent emergency surgery between January 2014 and June 2021. We performed univariate and multivariate analyses to identify independent objective predictors of gangrenous/perforated appendicitis, and a new scoring model was developed based on logistic regression coefficients for independent predictors. Receiver operating characteristic (ROC) curve analysis and the Hosmer-Lemeshow test were performed to assess the discrimination and calibration of the model. Finally, the scores were classified into three categories based on the probability of gangrenous/perforated appendicitis.

RESULTS

Among the 151 patients, 85 and 66 patients were diagnosed with gangrenous/perforated appendicitis and uncomplicated appendicitis, respectively. Using the multivariate analysis, C-reactive protein level, maximal outer diameter of the appendix, and presence of appendiceal fecalith were identified as independent predictors for developing gangrenous/perforated appendicitis. Our novel scoring model was developed based on three independent predictors and ranged from 0 to 3. The area under the ROC curve was 0.792 (95% confidence interval, 0.721-0.863), and the Hosmer-Lemeshow test showed a good calibration of the novel scoring model (P = 0.716). Three risk categories were classified: low, moderate, and high risk with probabilities of 30.9%, 63.8%, and 94.4%, respectively.

CONCLUSIONS

Our scoring model can objectively and reproducibly identify gangrenous/perforated appendicitis with good diagnostic accuracy and help in determining the degree of urgency and in making decisions about appendicitis management.

Risk factors for postoperative disseminated intravascular coagulation in surgical patients with non-occlusive mesenteric ischemia

PURPOSE

The prognostic impact of disseminated intravascular coagulation (DIC) in surgical patients with non-occlusive mesenteric ischemia (NOMI) is unclear. This study aimed to confirm the association between postoperative DIC and prognosis and to identify preoperative risk factors associated with postoperative DIC.

METHODS

This retrospective study included 52 patients who underwent emergency surgery for NOMI between January 2012 and March 2022. Kaplan-Meier curve analysis with the log-rank test was used to compare 30-day survival and hospital survival between patients with and without postoperative DIC. In addition, univariable and multivariable logistic regression analyses were performed to identify the preoperative risk factors for postoperative DIC.

RESULTS

The 30-day and hospital mortality rates were 30.8% and 36.5%, respectively, and the incidence rate of DIC was 51.9%. Compared to patients without DIC, patients with DIC showed significantly lower rates of 30-day survival (41.5% vs 96%, log-rank P < 0.001) and hospital survival (30.2% vs 86.4%, log-rank, P < 0.001). Logistic regression analyses showed that the Japanese Association for Acute Medicine (JAAM) DIC score (OR = 2.697; 95% CI, 1.408-5.169; P = 0.003) and Sequential Organ Failure Assessment (SOFA) score (OR = 1.511; 95% CI, 1.111-2.055; P = 0.009) were independent risk factors for postoperative DIC in surgical patients with NOMI.

CONCLUSION

The development of postoperative DIC is a significant prognostic factor for 30-day and hospital mortalities in surgical patients with NOMI. In addition, the JAAM DIC score and SOFA score have a high discriminative ability for predicting the development of postoperative DIC.

Total breast reconstruction with a fat-augmented latissimus dorsi flap: A comparative study between muscle and myocutaneous flaps

The fat-augmented latissimus dorsi myocutaneous flap can overcome the volume insufficiency of latissimus dorsi flaps by immediate fat grafting into the flap. When breast skin supplementation is unnecessary, latissimus dorsi flaps can be harvested as a muscle flap to avoid an additional back incision. Here, we compared the efficacy of fat-augmented latissimus dorsi myocutaneous and muscle flaps in total breast reconstruction. We retrospectively reviewed 94 cases of unilateral total breast reconstruction using fat-augmented latissimus dorsi flaps (muscle: 40, myocutaneous: 54) at our hospital from September 2017 to March 2022. The muscle flap group had a significantly shorter operative time than the myocutaneous flap group (p < 0.0001). Mastectomy specimen weight did not differ between the 2 groups, but total flap weight in the muscle flap group was significantly lower (p < 0.0001). Conversely, total fat graft volume, fat graft volume to the latissimus dorsi flap, and fat graft volume to the pectoralis major muscle were significantly greater in the muscle flap group (p < 0.0001, p < 0.0001, and p = 0.02, respectively). The percentage of cases requiring additional fat grafting was significantly higher in the muscle flap group, but postoperative esthetic evaluation did not significantly differ between the 2 groups. Both groups scored high on each BREAST-Q item, but the muscle flap group scored significantly higher for "Satisfaction with Back." Although the frequency of additional fat grafting was higher than with fat-augmented latissimus dorsi myocutaneous flaps, total breast reconstruction with fat-augmented latissimus dorsi muscle flaps is a viable technique with a short operative time and high patient satisfaction.

Recent advances in surgical techniques for breast reconstruction

Although the number of patients with breast cancer continues to rise worldwide, survival rates for these patients have significantly improved. As a result, breast cancer survivors are living longer, and quality of life after treatment is of increasing importance. Breast reconstruction is an important component that affects quality of life after breast cancer surgery. With the development of silicone gel implants in the 1960s, autologous tissue transfer in the 1970s, and tissue expanders in the 1980s, breast reconstruction has advanced over the decades. Furthermore, the advent of perforator flaps and introduction of fat grafting have rendered breast reconstruction a less invasive and more versatile procedure. This review provides an overview of recent advances in breast reconstruction techniques.

CTCF loss induces giant lamellar bodies in Purkinje cell dendrites

CCCTC-binding factor (CTCF) has a key role in higher-order chromatin architecture that is important for establishing and maintaining cell identity by controlling gene expression. In the mature cerebellum, CTCF is highly expressed in Purkinje cells (PCs) as compared with other cerebellar neurons. The cerebellum plays an important role in motor function by regulating PCs, which are the sole output neurons, and defects in PCs cause motor dysfunction. However, the role of CTCF in PCs has not yet been explored. Here we found that the absence of CTCF in mouse PCs led to progressive motor dysfunction and abnormal dendritic morphology in those cells, which included dendritic self-avoidance defects and a proximal shift in the climbing fibre innervation territory on PC dendrites. Furthermore, we found the peculiar lamellar structures known as "giant lamellar bodies" (GLBs), which have been reported in PCs of patients with Werdnig-Hoffman disease, 13q deletion syndrome, and Krabbe disease. GLBs are localized to PC dendrites and are assumed to be associated with neurodegeneration. They have been noted, however, only in case reports following autopsy, and reports of their existence have been very limited. Here we show that GLBs were reproducibly formed in PC dendrites of a mouse model in which CTCF was deleted. GLBs were not noted in PC dendrites at infancy but instead developed over time. In conjunction with GLB development in PC dendrites, the endoplasmic reticulum was almost absent around the nuclei, the mitochondria were markedly swollen and their cristae had decreased drastically, and almost all PCs eventually disappeared as severe motor deficits manifested. Our results revealed the important role of CTCF during normal development and in maintaining PCs and provide new insights into the molecular mechanism of GLB formation during neurodegenerative disease.

Detection of current-sheet and bipolar ion flows in a self-generated antiparallel magnetic field of laser-produced plasmas for magnetic reconnection research

Magnetic reconnection in laser-produced magnetized plasma is investigated by using optical diagnostics. The magnetic field is generated via the Biermann battery effect, and the inversely directed magnetic field lines interact with each other. It is shown by self-emission measurement that two colliding plasmas stagnate on a midplane, forming two planar dense regions, and that they interact later in time. Laser Thomson scattering spectra are distorted in the direction of the self-generated magnetic field, indicating asymmetric ion velocity distribution and plasma acceleration. In addition, the spectra perpendicular to the magnetic field show different peak intensity, suggesting an electron current formation. These results are interpreted as magnetic field dissipation, reconnection, and outflow acceleration. Two-directional laser Thomson scattering is, as discussed here, a powerful tool for the investigation of microphysics in the reconnection region.

Prediction model for irreversible intestinal ischemia in strangulated bowel obstruction

Background

Preoperatively diagnosing irreversible intestinal ischemia in patients with strangulated bowel obstruction is difficult. Therefore, this study aimed to establish a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction.

Methods

We included 83 patients who underwent emergency surgery for strangulated bowel obstruction between January 2014 and March 2022. The predictors of irreversible intestinal ischemia in strangulated bowel obstruction were identified using logistic regression analysis, and a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction was established using the regression coefficients. Receiver operating characteristic analysis and fivefold cross-validation was used to assess the model.

Results

The prediction model (range, 0–4) was established using a white blood cell count of ≥ 12,000/µL and the computed tomography value of peritoneal fluid that was ≥ 20 Hounsfield units. The areas of the receiver operating characteristic curve of the new prediction model were 0.814 and 0.807 after fivefold cross-validation. A score of ≥ 2 was strongly suggestive of irreversible intestinal ischemia in strangulated bowel obstruction and necessitated bowel resection (odds ratio = 15.938). The bowel resection rates for the prediction scores of 0, 2, and 4 were 15.2%, 66.7%, and 85.0%, respectively.

Conclusion

Our model may help predict irreversible intestinal ischemia that necessitates bowel resection for strangulated bowel obstruction cases and thus enable surgeons to recognize the severity of the situation, prepare for deterioration of patients with progression of intestinal ischemia, and select the appropriate surgical procedure for treatment.

High-power laser experiment on developing supercritical shock propagating in homogeneously magnetized plasma of ambient gas origin

A developing supercritical collisionless shock propagating in a homogeneously magnetized plasma of ambient gas origin having higher uniformity than the previous experiments is formed by using high-power laser experiment. The ambient plasma is not contaminated by the plasma produced in the early time after the laser shot. While the observed developing shock does not have stationary downstream structure, it possesses some characteristics of a magnetized supercritical shock, which are supported by a one-dimensional full particle-in-cell simulation taking the effect of finite time of laser-target interaction into account.

Direct observations of pure electron outflow in magnetic reconnection

Magnetic reconnection is a universal process in space, astrophysical, and laboratory plasmas. It alters magnetic field topology and results in energy release to the plasma. Here we report the experimental results of a pure electron outflow in magnetic reconnection, which is not accompanied with ion flows. By controlling an applied magnetic field in a laser produced plasma, we have constructed an experiment that magnetizes the electrons but not the ions. This allows us to isolate the electron dynamics from the ions. Collective Thomson scattering measurements reveal the electron Alfvénic outflow without ion outflow. The resultant plasmoid and whistler waves are observed with the magnetic induction probe measurements. We observe the unique features of electron-scale magnetic reconnection simultaneously in laser produced plasmas, including global structures, local plasma parameters, magnetic field, and waves.

HOXB9 mediates resistance to chemotherapy and patient outcomes through the TGFβ pathway in pancreatic cancer

BACKGROUND

Although HOXB9 induces tumor proliferation and chemoresistance in several cancer cells, little is known in pancreatic ductal adenocarcinoma (PDAC). In the present study, increased expression of HOXB9 in PDAC was associated with the induction of angiogenic factors and poor overall survival through the TGFβ pathway. Taken together, these results suggested that HOXB9 expression in PDAC could be a surrogate marker in clinical treatment.

METHODS

In vitro, angiogenic factors, TGFβ signature, Epithelial Mesenchymal Transition (EMT) marker, and chemoresistance were examined in PDAC cell lines by HOXB9 knockdown system. And the reverse effect was confirmed by using TGFβ1 recombinant. Furthermore, in clinical specimens, the correlation between HOXB9 expression and TGFβ signature was analyzed, and the relationship with clinical outcomes were investigated.

RESULTS

HOXB9 expression regulated the expression of TGFβ1 signature, angiogenic factors, and EMT markers in vitro, and TGFβ1 recombinant made the reverse effect of these results. And HOXB9 expression regulated the resistance to chemotherapy (Gemcitabine and nab-Paclitaxel) and stem cell population. Moreover, increased HOXB9 expression was significantly associated with poor disease-free survival the prognosis for overall survival. And, a significant positive correlation was observed between HOXB9 expression and several TGFβ signatures in clinical specimens.

CONCLUSIONS

In conclusion, HOXB9 expression could mediate angiogenesis, EMT, and cancer stemness through the TGFβ pathway, thereby resulting in chemoresistance and poor overall outcomes in patients with pancreatic cancer. Our results suggested that HOXB9 may clinically serve as a novel surrogate biomarker.

Hydrogen-generating Si-based agent protects against skin flap ischemia-reperfusion injury in rats

Hydrogen is effective against ischemia–reperfusion (I/R) injury in skin flaps. However, the difficulty of continuously administering a sufficient amount of hydrogen using conventional methods has been an issue in the clinical application of hydrogen-based therapy. An Si-based agent administered orally was previously shown to continuously generate a large amount of hydrogen in the intestinal environment. In this study, we assessed the effect of the Si-based agent on the inhibition of I/R injury in skin flaps using a rat model. In the I/R groups, the vascular pedicle of the abdominal skin flap was occluded for three hours followed by reperfusion. In the I/R + Si group, the Si-based agent was administered perioperatively. After reperfusion, flap survival rate, blood flow, oxidative stress markers, inflammatory markers/findings, and degree of apoptosis were evaluated. Flap survival rate was significantly higher, and histological inflammation, apoptotic cells, oxidative stress markers, and levels of inflammatory cytokine mRNA and protein expression were significantly lower, in the I/R + Si group compared to the I/R group. The Si-based agent suppressed oxidative stress, apoptosis, and inflammatory reactions resulting from I/R injury, thereby contributing to improvements in skin flap survival.

Sensory Reinnervation With Subcutaneously Embedded Innervated Flaps: An Experimental Study in Rats

BACKGROUND

In breast reconstruction, both aesthetic outcomes and sensory function are important for postoperative quality of life. Innervated flaps are useful in reconstruction after conventional mastectomy (CM), which leaves a large portion of the skin paddle exposed on the body surface. However, whether they are also useful in skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) remains unclear. This study aimed to examine the usefulness of innervated flaps in restoring sensation after SSM and NSM using a rat model.

METHODS

Dorsal cutaneous nerves of rats were entirely eliminated except for the medial branch of the dorsal cutaneous nerve of thoracic segment 13, resulting in an innervated field surrounded by a denervated field. The innervated field was elevated as an innervated island flap and then subcutaneously embedded, with the skin paddle deepithelialized entirely (NSM group, n = 5) or except at the center (SSM group, n = 6). In the control model (CM group, n = 5), the flap was sutured back into its original position. Postoperative changes in the mechanonociceptive field were evaluated using the cutaneous trunci muscle reflex test. Immunohistochemical evaluation of regenerated nerves in the new mechanonociceptive field was performed at postoperative week 12.

RESULTS

In the SSM and CM groups, the mechanonociceptive field expanded around the skin paddle. In the NSM group, a new mechanonociceptive field appeared at postoperative week 4 and expanded thereafter. Areas of the mechanonociceptive field at postoperative week 12 did not differ significantly between the SSM and NSM groups, but were significantly smaller compared with the CM group and comparable to original flap areas. Histologically, S100- and PGP9.5-positive nerve fibers were observed in the dermis of the new mechanonociceptive field and subcutaneous flap tissue.

CONCLUSIONS

Subcutaneously embedded innervated island flaps induced nerve regeneration and sensory reinnervation of the denervated skin, suggesting that innervated flaps may also be useful in reconstruction post-SSM/NSM.

Prognostic Impact of N2 of the Primary Tumour in Surgical Resection for Colorectal Liver Metastases

BACKGROUND/AIM

The status of lymph node metastasis of primary tumours remains to be completely investigated. This study investigated the prognostic impact of the degree of primary lymph node metastasis in patients with colorectal liver metastasis.

PATIENTS AND METHODS

We retrospectively analysed the clinical data of 106 patients with colorectal liver metastases who underwent surgical resection. Prognostic factors, including the degree of the positive primary lymph nodes, positive lymph node ratio, and log odds of positive lymph nodes, were evaluated.

RESULTS

The T factor and N2 status were independent risk factors for overall survival in patients who underwent surgical resection. Survival was significantly lower in the N2 group than in the N0-1 group. Additionally, ≥N2 status showed better prognostic performance than ≥N1 status.

CONCLUSION

N2 of primary tumours is an independent useful prognostic factor in colorectal liver metastasis and can help determine the indication of surgical resection and pre/post-operative chemotherapy.

Retropancreatic Nerve Plexus Hanging Maneuver for Pancreatoduodenectomy for Cancer of the Head of the Pancreas

The efficacy of the hanging maneuver for the retropancreatic nerve plexus (RNP) to enhance the confirmation of the margin status and to facilitate en-bloc resection for pancreatoduodenectomy is studied. The exit of the hanging maneuver of the RNP is the left part of the superior mesenteric artery, and the entry is the cranial part of the celiac axis. The entry of the hanging maneuver was connected to the dissection line on the right side of the celiac axis. Thereafter, the tape of the hanging maneuver was pulled to the right side, and the RNP was deployed widely. Finally, the RNP was easily dissected using a sealing device other than inferior pancreaticoduodenal artery. With the correct implementation of the hanging maneuver, we believe that it would be possible to obtain reliable R0 resection as well as a reduction in blood loss and operation time.

High-power laser experiment forming a supercritical collisionless shock in a magnetized uniform plasma at rest

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

Handling of Hilar Vasculature in Living Donor Right Hepatectomy Using Extrahepatic Glissonean Approach

Donor hepatectomy is one of the most important procedures in LDLT because it affects the safety of donors and the outcome of the recipients. We standardized a method of securing the important vessels at the hepatic hilum while advancing the dissection toward the central direction. This research introduces our technique of handling hilar vasculature in living donor hepatectomy, using the extrahepatic Glissonean approach, and discusses its efficacy. At first, after the extrahepatic right Glissonean approach, the resected hepatic artery and portal vein are secured on the same line as with the secured Glisson. The resected hepatic artery and portal vein are followed in the central direction, and the surrounding area is dissected. The dissection is continued up to the main brunch of the hepatic artery and portal vein. The bile duct can be secured by subtracting the hepatic artery and portal vein from the tape that secured the Glissonean pedicle. The bile duct, hepatic artery, and the portal vein are dissected in this order, before dissecting the right hepatic vein, completing the surgery. This method of dissection approaching the extrahepatic Glisson carried out toward the central direction suggests to acquire minimal tissue removal and to shorten operative time. This could result in adequate perfusion to the remaining liver and donor safety, taken together effective results on the recipient.

Prediction Model for Failure of Nonoperative Management of Uncomplicated Appendicitis in Adults

BACKGROUND

Prediction of failure of nonoperative management (NOM) in uncomplicated appendicitis (UA) is difficult. This study aimed to establish a new prediction model for NOM failure in UA.

METHODS

We included 141 adults with UA who received NOM as initial treatment. NOM failure was defined as conversion to operation during hospitalization. Independent predictors of NOM failure were identified using logistic regression analysis. A prediction model was established based on these independent predictors. Receiver operating characteristic (ROC) curve analysis and the Hosmer-Lemeshow test were used to assess the discrimination and calibration of the model, respectively, and risk stratification using the model was performed.

RESULTS

Among 141 patients, NOM was successful in 120 and unsuccessful in 21. Male sex, maximal diameter of the appendix, and the presence of fecalith were identified as independent predictors of NOM failure for UA. A prediction model with scores ranging from 0 to 3 was established using the three variables (male sex, maximal diameter of the appendix ≥ 15 mm, and the presence of fecalith). The area under the ROC curve for the new prediction model was 0.778, and the model had good calibration (P = 0.476). A score of 2 yielded a sensitivity of 71.4% and a specificity of 90.8%. Patients were stratified into low (0-1), moderate (2), and high (3) risk categories, which had NOM rates of 5.2%, 47.1%, and 77.8%, respectively.

CONCLUSIONS

Our prediction model may predict NOM failure in UA with good diagnostic accuracy and help surgeons select appropriate treatments.

New risk factors of postoperative complications in elective gastrointestinal surgery of elderly patients: a prospective cohort study

BACKGROUND

Gastrointestinal surgery in elderly individuals presents unexpected postoperative complications. However, predicting postoperative complications in elderly patients undergoing gastrointestinal surgeries is challenging because of the lack of a reliable preoperative evaluation system. We aimed to prospectively evaluate three new preoperative assessment methods to predict the postoperative complications in elderly patients undergoing elective gastrointestinal surgery. Moreover, we aimed to identify new risk factors of postoperative complications in this patient group.

METHODS

This prospective cohort study enrolled 189 patients (age ≥ 65 years) who underwent elective gastrointestinal surgery at Tokyo Medical University Hachioji Medical Center between April 2017 and March 2019. Assessments performed preoperatively included the biological impedance analysis for evaluating the skeletal muscle mass, the SF-8 questionnaire for evaluating the subjective health-related quality of life, and the blood pressure/pulse wave test for assessing arteriosclerosis. The risk factors for Clavien-Dindo Grade ≥ III postoperative complications were assessed using these new evaluation methods.

RESULTS

Clavien-Dindo Grade ≥ III postoperative complications were observed in 28 patients (14.8%). Univariate and multivariate analyses identified male sex, low skeletal muscle mass, and cardio-ankle vascular index ≥ 10 (arteriosclerosis) as significant independent risk factors of developing Grade ≥ III complications.

CONCLUSIONS

Male sex, low skeletal muscle mass, and arteriosclerosis were significant risk factors of postoperative complications in elderly patients undergoing elective gastrointestinal surgery. The obtained knowledge could be useful in identifying high-risk patients who require careful perioperative management.

Ganglioside GD3 May Suppress the Functional Activities of Benign Skin T Cells in Cutaneous T-Cell Lymphoma

In cutaneous T-cell lymphoma (CTCL), which arises from skin-tropic memory T cells, malignant T cells and benign T cells are confined in the same skin lesions. It is thus difficult to evaluate the phenotypic characteristics and functional activities of benign T cells in CTCL. Disialoganglioside with three glycosyl groups (GD3) is increasingly expressed on the surface of solid malignant tumor cells and takes part in tumor progression and suppression of tumor immunity. However, the role of GD3 in CTCL is not well-understood. In this study, the malignant and benign T cells in CTCL skin lesions were distinguished by flow cytometry and their phenotypic characteristics were compared with those of T cells from control skin specimens. In CTCL skin lesions, the benign T cells included limited resident memory T cells (T_RM), which are sessile in skin and known to exert strong antitumor function. The benign T cells showed diminished Th17 property, and the expression of GD3 was high in the malignant T cells. The expression of GD3 in the malignant T cells inversely correlated with IL-17A production from the benign CD4 T cells. GD3 from the malignant T cells was implied to be involved in suppressing the Th17 activity of the benign T cells independent of the regulation of T_RM differentiation in CTCL. Revealing the role of GD3 in inhibiting the production of IL-17A in CTCL would aid the understanding of the suppressive mechanism of the antitumor activity by malignant tumor cells.

Reforestation provides a foraging habitat for brown bears (Ursus arctos) by increasing cicada Lyristes bihamatus density in the Shiretoko World Heritage site

Reforestation, which converts abandoned farmland back into forestland by planting woody species, can provide habitat for wildlife, including the brown bear (Ursus arctos Linnaeus, 1758). In the Shiretoko World Heritage site, northern Japan, where brown bears occur at high density, conifers have been planted since the 1970s to reforest abandoned farmland. In this area, brown bears were first observed digging for cicada Lyristes bihamatus Motschulsky, 1861 = Auritibicen bihamatus (Motschulsky, 1861) nymphs from 2000. Our preliminary observations suggested that the emergence of digging behavior might be associated with reforestation. We examined whether reforestation provided a foraging habitat for brown bears. We found that digging occurred only within the restored conifer forests, but not within the natural forest. The densities of cicada nymphs in the restored forests were higher than in the natural forest. These results indicate that the reforestation of abandoned farmland provides a foraging habitat for brown bears by increasing the availability of cicada nymphs in the Shiretoko World Heritage site.

Efficacy of Low Power, Pure Cut Mode of Monopolar Electrosurgery and Quilting Sutures for Preventing Seroma Formation After Latissimus Dorsi Myocutaneous Flap Harvest

BACKGROUND

Latissimus dorsi myocutaneous (LD) flaps are widely used in breast reconstruction surgery. However, seromas often form postoperatively at the donor site as a complication. This study aimed to determine the impact of different electrocautery modes during flap elevation, with or without subsequent quilting sutures, on postoperative seroma formation.

METHODS

Subjects were 112 patients who underwent immediate breast reconstruction with LD flaps after breast-conserving surgery between April 2015 and January 2019. Group A consisted of 21 patients who underwent LD flap elevation using the fulgurate mode, and group B consisted of 25 patients who underwent flap elevation using the lower power, pure cut mode. Group C consisted of 66 patients who underwent flap elevation with the lower power, pure cut mode combined with quilting sutures for wound closure.

RESULTS

Mean 1-week postoperative back drain volume and the mean number of days to drain removal in group B were significantly reduced relative to those in group A (group A, 752.3 mL and 16.9 days, respectively; group B, 552.2 mL and 10.6 days, respectively; P < 0.001 for both). Group C, which included quilting sutures, had even lower values than group B (459.7 mL and 7.4 days, respectively; group B vs group C: P = 0.03 and P < 0.001, respectively). Significant differences were observed between groups for postoperative seroma formation at the flap donor site (group A, 16 [76.2%] of 21 patients; group B, 11 [44%] 25 patients; group C, 4 [6.1%] of 66 patients; A vs B: P < 0.001, B vs C: P < 0.001).

CONCLUSIONS

The use of low power, pure cut mode for LD flap harvest, combined with quilting sutures, effectively shortened the time to drain removal and suppressed seroma formation. Given that specialized devices and materials are not required, this combination may reduce both patient burden and medical costs.

Prognostic value of future liver remnant LU15 index of 99mTc-galactosyl serum albumin scintigraphy for predicting posthepatectomy liver failure

There is no gold standard indicator that is currently used to predict posthepatectomy liver failure (PHLF). A novel indicator of liver function, the LU15 index of ^99mTc-galactosyl serum albumin (GSA) scintigraphy, refers to the liver uptake ratio over a 15-min interval. We aimed to evaluate the usefulness of the future liver remnant (FLR)-LU15 in predicting PHLF. The clinical data of 102 patients (70 males and 32 females; median age, 70 years) who underwent liver resection between January 2011 and August 2019 were analyzed. The FLR-LU15 was calculated by a fusion of simulated 3-dimensional images and ^99mTc-GSA scintigraphy. PHLF was determined according to the definition of the International Study Group of Liver Surgery. The FLR-LU15 was an independent risk factor for PHLF ≥ Grade B according to multivariate analysis, and its value correlated with the PHLF grade. The area under the receiver operating characteristic curve of the FLR-LU15 for PHLF ≥ Grade B was 0.816 (95% confidence interval, 0.704–0.929), which was better than that of other indicators. When the cut-off value of FLR-LU15 was set at 16.7, the sensitivity was 86.7%, specificity was 74.7%, and odds ratio was 19.2 (95% confidence interval, 4.0–90.9), all of which were superior to other indicators. If the cut-off value was 13, the positive predictive value was 57.1%. The FLR-LU15 is a useful predictor of PHLF and may be more reliable than other predictors.

Efficacy of the Milan criteria as a prognostic factor in patients with colorectal liver metastases

PURPOSE

This study aimed to apply the principles of the "Milan criteria" to patients undergoing hepatic resection for CRLM and to evaluate the efficacy of prognostic factors.

METHODS

The medical records of consecutive patients who underwent curative resection for CRLM from April 2007 to April 2019 were retrospectively reviewed. Time to aggressive treatment failure (TATF) was defined as the time interval from the initial surgery until the first unresectable recurrence or recurrence that could only be treated with doublet or lower dose chemotherapy, or death. The risk factors associated with recurrence-free survival (RFS), TSF, TATF, and overall survival (OS) were evaluated.

RESULTS

On univariate analysis, the Milan criteria significantly predicted long-term OS, TATF, TSF, and RFS. Moreover, the Milan criteria were able to stratify patients with CRLM into distinct prognostic groups with regard to long-term OS, TATF, TSF, and RFS.

CONCLUSIONS

Milan criteria, a simple index, are a factor contributing to all the survival time and are a very important factor in discussing the prognosis of CRLM.

A New Preoperative Risk Score for Predicting Postoperative Complications in Elderly Patients Undergoing Hepatectomy

BACKGROUND

Postoperative complications are not rare in the elderly population after hepatectomy. However, predicting postoperative risk in elderly patients undergoing hepatectomy is not easy. We aimed to develop a new preoperative evaluation method to predict postoperative complications in patients above 65 years of age using biological impedance analysis (BIA).

METHODS

Clinical data of 59 consecutive patients (aged 65 years or older) who underwent hepatectomy at our institution between 2017 and 2020 were retrospectively analyzed. Risk factors for postoperative complications (Clavien-Dindo ≥ III) were evaluated using multivariate regression analysis. Additionally, a new preoperative risk score was developed for predicting postoperative complications.

RESULTS

Fifteen patients (25.4%) had postoperative complications, with biliary fistula being the most common complication. Abnormal skeletal muscle mass index from BIA and type of surgical procedure were found to be independent risk factors in the multivariate analysis. These two variables and preoperative serum albumin levels were used for developing the risk score. The postoperative complication rate was 0.0% with a risk score of ≤ 1 and 57.1% with a risk score of ≥ 4. The area under the receiver operating characteristic curve of the risk score was 0.810 (p = 0.001), which was better than that of other known surgical risk indexes.

CONCLUSION

Decreased skeletal muscle and the type of surgical procedure for hepatectomy were independent risk factors for postoperative complications after elective hepatectomy in elderly patients. The new preoperative risk score is simple, easy to perform, and will help in the detection of high-risk elderly patients undergoing elective hepatectomy.

Protocol for a multicentre, prospective, cohort study to investigate patient satisfaction and quality of life after immediate breast reconstruction in Japan: the SAQLA study

INTRODUCTION

The aim of breast reconstruction (BR) is to improve patients' health-related quality of life (HRQOL). Therefore, measuring patient-reported outcomes (PROs) would clarify the value and impact of BR on a patient's life and thus would provide evidence-based information to help decision-making. The Satisfaction and Quality of Life After Immediate Breast Reconstruction study aimed to investigate satisfaction and HRQOL in Japanese patients with breast cancer who undergo immediate breast reconstruction (IBR).

METHODS AND ANALYSIS

This ongoing prospective, observational multicentre study will assess 406 patients who had unilateral breast cancer and underwent mastectomy and IBR, and were recruited from April 2018 to July 2019. All participants were recruited from seven hospitals: Okayama University Hospital, Iwate Medical University Hospital, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, Showa University Hospital, University of Tsukuba Hospital, Osaka University Hospital and Yokohama City University Medical Center. The patients will be followed up for 36 months postoperatively. The primary endpoint of this study will be the time-dependent changes in BREAST-Q satisfaction with breast subscale scores for 12 months after reconstructive surgery, which will be collected via an electronic PRO system.

ETHICS AND DISSEMINATION

This study will be performed in accordance with the Ethical Guidelines for Medical and Health Research Involving Human Subjects published by Japan's Ministry of Education, Science and Technology and the Ministry of Health, Labour and Welfare, the modified Act on the Protection of Personal Information and the Declaration of Helsinki. This study protocol was approved by the institutional ethics committee at the Okayama University Graduate School of Medicine, Dentistry, on 2 February 2018 (1801-039) and all other participating sites. The findings of this trial will be submitted to an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

UMIN000032177.

Targeted sensory reinnervation by direct neurotization of skin: An experimental study in rats

BACKGROUND

No effective methods currently exist for breast neurotization in implant-based breast reconstruction. Here, we focused on direct neurotization (DN), in which axons regenerating from nerve stumps are directed to the mastectomy flap and aimed to assess whether DN can generate a new mechano-nociceptive field using a rat model of back skin sensory denervation.

METHODS

Dorsal cutaneous nerves (DCNs) of rats were exposed and transected, leaving only the left medial branch of the DCN of thoracic segment 13 (mDCN-T13) intact. This procedure resulted in an isolated innervated field surrounded by a denervated field. The mDCN-T13 was transected, and the proximal nerve stump was sutured to the subdermis (DN subdermal group, n = 6) or dermis (DN dermal group, n = 5) of a different region of the denervated field. In the Crush group (n = 5), the intact mDCN-T13 was only crushed. We evaluated the generation of a new mechano-nociceptive field over time using the cutaneous trunci muscle (CTM) reflex test and histomorphometrically evaluated regenerating nerves in the reinnervated region.

RESULTS

In the DN groups, the CTM reflex appeared in the DN area after postoperative week 4. The new mechano-nociceptive field gradually expanded afterwards, and by postoperative week 12, the area was substantially larger than the original region innervated by the mDCN-T13 in the DN dermal group, although not as large as that in the Crush group. In histomorphometric evaluations, many S100-positive myelinated fibers were observed in the dermis of the reinnervated area for all groups.

CONCLUSION

In targeted sensory reinnervation, DN of the skin is revolutionary in that it allows a new innervated area to be generated at a desired location regardless of whether a distal nerve stump is available. DN may present an effective approach for breast neurotization in breast reconstruction after mastectomy, particularly for procedures that cannot use sensate flaps such as implant-based breast reconstruction.

Prognostic Significance of Plasma Fibrinogen/Serum Albumin Ratio in the Postoperative Outcome of Pancreatic Ductal Adenocarcinoma

BACKGROUND/AIM

Surgery is an important pancreatic ductal adenocarcinoma (PDAC) treatment; existing markers are inadequate prognostic indexes. We herein evaluated the utility of the FA score (fibrinogen/albumin ratio) for predicting PDAC postoperative outcomes.

PATIENTS AND METHODS

We analysed the data of 67 PDAC patients who underwent surgical resection. The relationship between postoperative outcomes and the FA score was investigated. Performance of the FA score was compared to that of other variables and prognostic indexes.

RESULTS

No patient with FA ≥130 survived >3 years, whereas all patients who survived longer had FA <130. The FA score was superior to all other indexes for predicting postoperative outcomes. Patients with FA ≥130 vs. <130 had significantly shorter overall and recurrence-free survival.

CONCLUSION

The FA score is useful for predicting PDAC postoperative outcomes. Preoperatively, it may detect patients likely to have poor postoperative prognoses who may benefit from adjuvant or neoadjuvant therapy, thus improving outcomes.

[A Case of Left Transverse Colon Cancer Safely Resected Using Three-Dimensional CT Angiography and Indocyanine Green Fluorography]

A 77-year-old man was admitted to our hospital because of a positive occult blood test result and diagnosed as having left transverse colon cancer(cT2N0M0)on detailed examination. The patient underwent a sigmoidectomy for colon cancer 24 years previously. Three-dimensional(3D)-CT angiography was performed before the present operation. The left branch of the middle colic artery, which was independently branched, and the marginal artery of the colon were found to be supplying blood from the left side of the transverse colon to the anastomosis of the sigmoid colon. In addition, the root of the left branch of the middle colic artery arose from the caudal side of the first jejunal vein. Therefore, a left hemicolectomy was performed. In accordance with the preoperative simulation, we safely resected the left branch of the middle colic artery at the root. Intraoperative blood flow evaluation using indocyanine green(ICG)fluorography clearly displayed the demarcation of the oral blood flow and the point of anastomosis. No notable complications occurred after the surgery. The results of the pathological analyses indicated a pT1bN0M0 tumor stage. Therefore, we conclude that 3D-CT angiography and ICG fluorography are useful for performing safer operations for left transverse colon cancers.

Fat-augmented latissimus dorsi myocutaneous flap for total breast reconstruction: A report of 54 consecutive Asian cases

Immediate fat grafting to the latissimus dorsi myocutaneous (LD) flaps is a breakthrough that addresses the issue of insufficient volume of LD. However, the use of this procedure in Asian patients has not yet been reported. Retrospective chart reviews were conducted on 54 Japanese cases of total breast reconstruction using fat-augmented LD flaps at our hospital from September 2017 to June 2019. There were 24 immediate reconstruction cases, 18 immediate two-stage reconstruction cases, nine delayed reconstruction cases, and three delayed two-stage reconstruction cases. Median age was 46 years (range, 29-69 years), and median body mass index was 21.5 (17-33.8). Median mastectomy specimen and flap weight was 225 g (123-993) and 225 g (130-796), respectively. The median volume of fat graft was 114 ml (46-305) for the LD flap and 58 ml (15-200) for the pectoralis major muscle. Of the 53 completed reconstruction cases, 38 (71.7%) achieved sufficient volume with the initial operation and six (11.3%) required additional fat grafting. The proportion of cases in the immediate reconstruction group, which achieved sufficient volume in the initial operation was significantly higher than those of the other three reconstruction groups (p = 0.007). Total breast reconstruction with fat-augmented LD flaps is a viable procedure for thin patients who have insufficient abdominal tissue, for those who wish to avoid abdominal scars, and for those in whom abdominal flaps have already been used. The procedure allows for large volume transplantation even with small skin paddles, which allows for smaller skin paddles to be designed without the need for extensive subcutaneous dissection.

Living donor liver transplantation for idiopathic portal hypertension with extrahepatic portal vein stenosis and splenic artery aneurysms: a case report and review of the literature

Background

Idiopathic portal hypertension (IPH) generally has a good prognosis and rarely results in liver transplantation. Furthermore, there are few reports of living donor liver transplantation (LDLT) for IPH with extrahepatic portal vein stenosis.

Case presentation

We report the case of a 51-year-old female patient diagnosed with IPH more than 20 years ago. She suffered severe jaundice, massive ascites, and encephalopathy at the time of her visit to our hospital. The patient’s extrahepatic portal vein showed a scar-like stenosis, and the portal flow was completely hepatofugal. Collateral circulation such as the splenorenal shunt was well developed, and multiple splenic artery aneurysms up to 2 cm were observed in the splenic hilum. Her Model for End-Stage Liver Disease score increased to over 40 because of renal dysfunction, requiring temporary dialysis. We performed LDLT using her husband’s right lobe graft and splenectomy. The extrahepatic stenotic portal vein was completely resected, and the superficial femoral vein (SFV) graft collected from the recipient’s right leg was used for portal reconstruction as an interposition graft. Although the clinical course after LDLT had many complications, the patient was discharged on postoperative day 113 and has been fine for 2 years after LDLT. Histopathologically, the explanted liver had obliterative portal venopathy, nodular regenerative hyperplasia, and incomplete septal cirrhosis.

Conclusion

This case showed that severe IPH is occasionally associated with extrahepatic portal vein stenosis and can be treated with LDLT with portal vein reconstruction using an interposition graft. It was also suggested that the SFV is a useful choice for the interposition graft.

Testosterone Supplementation Rescues Spermatogenesis and In Vitro Fertilizing Ability of Sperm in Kiss1 Knockout Mice

Restoration of spermatogenesis and fertility is a major issue to be solved in male mammals with hypogonadotropic hypogonadism. Kiss1 knockout (KO) male mice are postulated to be a suitable animal model to investigate if hormonal replacement rescues spermatogenesis in mammals with this severe reproductive hormone deficiency, because KO mice replicate the hypothalamic disorder causing hypogonadism. The present study investigated whether testosterone supplementation was able to restore spermatogenesis and in vitro fertilization ability in Kiss1 KO mice. To this end, spermatogenesis, in vitro fertilization ability of Kiss1 KO sperm, and preimplantation development of wild-type embryos inseminated with Kiss1 KO sperm, were examined. The newly generated Kiss1 KO male mice showed infertility with cryptorchidism. Subcutaneous testosterone supplementation for 6 weeks restored plasma and intratesticular testosterone levels, elicited testicular descent, and induced complete spermatogenesis from spermatocytes to elongated spermatids in the testis, resulting in an increase in epididymal sperm number in testosterone-supplemented Kiss1 KO male mice. Epididymal sperm derived from the testosterone-supplemented Kiss1 KO mice showed normal in vitro fertilization ability, and the fertilized eggs showed normal preimplantation development, while the males failed to impregnate females. These results suggest that the failure of spermatogenesis in Kiss1 KO mice is mainly due to a lack of testosterone production, and that Kiss1 KO sperm are capable of fertilizing eggs if the animals receive the appropriate testosterone supplementation without local kisspeptin signaling in the testis and epididymis. Thus, testosterone supplementation would restore spermatogenesis of male mammals showing hypogonadotropic hypogonadism with genetic inactivation of the KISS1/Kiss1 gene.

Overexpression of hydroxyproline via EGLN/HIF1A is associated with distant metastasis in pancreatic cancer

For pancreatic cancer, the probability of distant metastasis can help choose the best course of treatment. The aim of this study is to establish the efficacy of hydroxyproline as a biomarker for distant metastasis for pancreatic cancer and to clarify the mechanism of EGLN/HIF1A axis that controls the invasion and metastasis. Metabolites (hydroxyproline) and genes (EGLN2 and EGLN3) were identified by metabolome analysis of the serum with pancreatic cancers with and without distant metastasis. The mechanism of EGLN/HIF1A axis including angiogenesis was examined in pancreatic cancer cells. Hydroxyproline associated with these mechanisms was evaluated to suggest the association with overall survival in pancreatic cancer. Decreased expression of EGLN2 and EGLN3 in pancreatic cancer, via the HIF1A and TGF ß1 pathway, was associated with the induction of angiogenic factors, increased vascular invasion, and poor overall patient survival. Hydroxyproline concentrations were regulated via the HIF1A pathway by EGLN2 and EGLN3, and that increased concentrations of hydroxyproline promote the invasion and metastasis of pancreatic cancer cells. These results suggested that the expression of hydroxyproline through the HIF1A pathway induced by EGLN2 and EGLN3 could be a surrogate marker for treatment and might predict distant metastasis in pancreatic cancer.

Resection of recurrent hepatocellular carcinoma with thrombi in the inferior vena cava, right atrium, and phrenic vein: a report of three cases

Background

Prognosis for patients with advanced hepatocellular carcinoma with a tumor thrombus in the inferior vena cava or right atrium is extremely poor due to cancer progression, pulmonary embolism, and congestion of the circulatory system caused by right heart failure. Surgical resection of the tumor thrombi may potentially yield better results than non-surgical treatments through prevention of sudden death. However, the benefits of surgical resection in patients with hepatocellular carcinoma and a tumor thrombus extending to the inferior vena cava, right atrium, and potentially in the phrenic vein are unclear. Here, we report three such cases.

Case presentation

Of the total 136 patients who underwent hepatectomies for hepatocellular carcinoma in our institution, three patients with prior hepatectomies and recurrent hepatocellular carcinoma had tumor thrombi in the inferior vena cava, right atrium, and phrenic vein. Surgical resections were performed, as there was a possibility of sudden death, despite the risk of leaving residual tumor. For all patients, we performed resection of the tumor thrombi in the inferior vena cava and right atrium and combined diaphragm resection. Surgical resection was performed using the total hepatic vascular exclusion technique in all cases. Additional passive veno-venous bypass was also performed in two cases, in which complete tumor resections could not be achieved. The microscopic surgical margins of the combined resected diaphragms were positive in all cases. Progression-free survival was 20.2, 3.8, and 9.5 months for case 1, 2, and 3, respectively. The respective overall postoperative survival was 98.0, 38.9, and 30.9 months. The patients died due to liver cirrhosis, acute heart failure, and hepatocellular carcinoma, respectively. Sudden death did not occur for any of the patients.

Conclusion

Surgical resections may extend prognosis for patients with recurrent hepatocellular carcinoma with tumor thrombi in the inferior vena cava, right atrium, and phrenic vein, although the indications should be considered carefully.

Right trisectionectomy for liver metastasis of granulosa cell tumor: a case report and literature review

BACKGROUND

Granulosa cell tumor (GCT) is a type of ovarian sex cord-stromal tumor with low-grade malignancy, which can recur long after primary resection. All reports on GCTs in the liver describe cases of metastases, while there are no previous reports of primary GCTs originating from the liver. We report a case of GCT, with recurrence of liver metastasis long after ovariectomy, which was subsequently resected by a right trisectionectomy.

CASE PRESENTATION

A 76-year-old woman presented with a history of surgical resection of an ovarian tumor performed 30 years previously; no details of the tumor were available. When she was 68 years old, an abdominal ultrasound revealed a small liver mass, which was diagnosed as a hepatic hemangioma with slow growth. Outpatient follow-up was discontinued for 5 years, and the patient was not examined again until the age of 76 years. At this point, the tumor had substantially increased in size, and surgical resection was required owing to suspicion of malignancy. The patient was then referred to our hospital. Contrast-enhanced computed tomography (CT) showed a large tumor, approximately 18 cm in size, occupying the right lobe and medial section of the liver. After percutaneous transhepatic portal vein embolization, a right trisectionectomy was performed. The histopathological findings of the resected specimen showed that the tumor cells had "coffee bean-like" nuclear grooves, which are characteristic of a GCT. Acidophilic non-structural Call-Exner bodies were also observed. Inhibin-α, CD99, and CD56 markers of sex cord-stromal tumors were detected on immunohistological examination; all pathology suggested a GCT. We considered the tumor to be a liver metastasis of a previous ovarian GCT that was resected 30 years prior by ovariectomy. There was no recurrence for > 15 months after the hepatectomy.

CONCLUSIONS

We report a case of a GCT in the liver, which was identified to be a liver metastasis. Right trisectionectomy was subsequently performed for tumor resection. Clinicians should be aware that ovarian GCTs may recur in the liver, and that GCT recurrence may occur long after ovariectomy of the primary ovarian GCT.