Displaced center of pressure on the treated side in individuals with essential tremor after radiofrequency ablation: a longitudinal case-control study.

Background: Essential tremor (ET) is a common involuntary movement disorder (IMD). Radiofrequency ablation (RFA) targeting the ventral intermediate nucleus (Vim) of the thalamus is a stereotactic neurosurgery performed in individuals with ET when pharmacotherapy is no longer effective. Though the reasons remain largely unclear, certain adverse events are known to appear post-RFA. These may be due to functional changes in the Vim, related to RFA-induced tremor reduction, or an adverse reaction to compensatory movement patterns used to perform movements in the presence of tremor symptoms. Objective: This study aimed to understand the characteristics of post-RFA symptoms in individuals with ET. Methods: In a longitudinal case-control study, we compared post-RFA symptoms between individuals with ET who underwent Vim-targeted RFA and those with IMD who underwent non-Vim-targeted RFA. Symptoms were compared preoperatively and 1-week and 1-month postoperatively. Quantitative assessments included center-of-pressure (COP) parameters, grip strength, Mini-Mental State Examination, two verbal fluency tests, and three types of physical performance assessments (upper extremity ability, balance ability, and gait ability). Results: Individuals with ET after RFA showed horizontal displacements of the COP to the treated side (the dominant side of the RFA target's hemisphere) at 1-week postoperatively compared to the preoperative period. The horizontal COP displacement was associated with balance dysfunction related to postural stability post-RFA. Other COP parameters did not significantly differ between the ET and IMD groups. Conclusion: COP displacement to the treated side may be due to a time lag in adjusting postural holding strategies to the long-standing lateral difference in tremor symptoms associated with tremor improvement after RFA.

Does repeat laparoscopic hepatectomy without extracorporeal Pringle manoeuvre worsen treatment outcomes?

Introduction: The Pringle manoeuvre is used in most hospitals to counteract intraoperative haemorrhage in laparoscopic hepatectomy by occluding the flow of blood to the liver. However, in laparoscopic repeat hepatectomy (LRH), outcomes of previous surgery and the influence of other factors frequently make it difficult to occlude the inflow of blood. Aim: To discuss the value of inflow occlusion during LRH and provide tips for its performance. Material and methods: Sixty-three patients who underwent LRH with or without the Pringle manoeuvre were analysed retrospectively. We investigated the efficacy and safety of the Pringle manoeuvre in LRH. Student's t and χ2 tests, Mann-Whitney's U test, Wilcoxon's signed-rank test, and Fisher's exact test were used in the statistical analysis. Results: Nineteen patients underwent LRH with the Pringle manoeuvre, and 44 patients underwent LHR without the Pringle manoeuvre. After propensity score matching, there were no significant differences in terms of operative time, estimated blood loss, and postoperative complication rate (p = 0.973, 0.120, and not applicable, respectively). However, the rate of conversion to open repeat hepatectomy (ORH) was significantly lower in the Pringle manoeuvre group (p = 0.034). In many cases, the cause of conversion to ORH was the non-use of inflow occlusion and the resulting inability to control intraoperative haemorrhage. Laboratory data collected after surgery showed no significant difference between the 2 groups regardless of whether blood flow was occluded or not. Conclusions: LRH with the Pringle manoeuvre can be performed safely using various surgical devices. However, it is often challenging to perform the Pringle manoeuvre in patients with a history of cholecystectomy or segment 5 resection of the liver, and caution is required.

The Management of Recurrence of Hepatocellular Carcinoma Occurring Within 6 Months After Hepatic Resection: A Comparative Study Using a Propensity Score Matching Analysis.

BACKGROUND: Hepatectomy is currently recommended as the most reliable treatment for hepatocellular carcinoma. However, the association between the choice of treatment for recurrence and the timing of recurrence remains controversial. METHODS: Three-hundred thirty-nine patients who underwent hepatectomy were retrospectively analyzed using a propensity score matching analysis for the risk factors and outcomes for early recurrences within 6 months. The remnant liver volumes and laboratory data were measured postoperatively using multidetector computed tomography on days 7 and months 1, 2, and 5 after surgery. The Student's t test and chi-square test, the likelihood-ratio test, Fisher's exact test, Mann-Whitney U test, or Wilcoxon signed-rank test were used in the statistical analyses. RESULTS: Early recurrence developed in 41/312 patients (13.1%). Vascular invasion and non-curative resection were independent risk factors for the occurrence of early recurrence (P < 0.001 and < 0.001, respectively). Patients with early recurrence had a poorer prognosis than patients who developed later recurrences (P < 0.001). Patients who underwent surgery or other local treatments had better outcomes (P < 0.001). The changes in remnant liver volumes and laboratory data after postoperative month 2 were not significantly different between the two groups. CONCLUSION: Patients with early recurrence within 6 months had a poorer prognosis than patients who developed a later recurrence. However, patients who underwent repeat hepatectomy for recurrences had a better prognosis than did those who underwent other treatments, with good prospects for long-term survival.

Subseafloor sulphide deposit formed by pumice replacement mineralisation.

Seafloor massive sulphide (SMS) deposits, modern analogues of volcanogenic massive sulphide (VMS) deposits on land, represent future resources of base and precious metals. Studies of VMS deposits have proposed two emplacement mechanisms for SMS deposits: exhalative deposition on the seafloor and mineral and void space replacement beneath the seafloor. The details of the latter mechanism are poorly characterised in detail, despite its potentially significant role in global metal cycling throughout Earth's history, because in-situ studies require costly drilling campaigns to sample SMS deposits. Here, we interpret petrographic, geochemical and geophysical data from drill holes in a modern SMS deposit and demonstrate that it formed via subseafloor replacement of pumice. Samples from the sulphide body and overlying sediment at the Hakurei Site, Izena Hole, middle Okinawa Trough indicate that sulphides initially formed as aggregates of framboidal pyrite and matured into colloform and euhedral pyrite, which were replaced by chalcopyrite, sphalerite and galena. The initial framboidal pyrite is closely associated with altered material derived from pumice, and alternating layers of pumiceous and hemipelagic sediments functioned as a factory of sulphide mineralisation. We infer that anhydrite-rich layers within the hemipelagic sediment forced hydrothermal fluids to flow laterally, controlling precipitation of a sulphide body extending hundreds of meters.

The Effects of Allogeneic Blood Transfusion in Hepatic Resection.

BACKGROUND: Hepatectomy has a high risk of perioperative bleeding due to the underlying disease. Here, we investigated the postoperative impact of allogeneic blood transfusion during hepatectomy. METHODS: The surgical outcomes in 385 patients who underwent hepatic resection for hepatocellular carcinoma were retrospectively reviewed. The association of allogeneic blood transfusion with surgical outcomes and remnant liver regeneration data was analyzed. RESULTS: Eighty-six patients (24.0%) received an allogeneic blood transfusion and 272 patients (76.0%) did not. After propensity score matching, the incidence rates of postoperative complication (Clavien-Dindo grade >IIIA), posthepatectomy liver failure, and massive ascites were significantly higher for the group that received a blood transfusion than for the group that did not receive blood transfusion (P < .001, P = .001, and <.001, respectively). Postoperative measures of total bilirubin, albumin, platelet count, prothrombin time, aspartate aminotransferase, and alanine aminotransferase were significantly more favorable in patients without blood transfusion until day 7 after surgery. There were no correlations in the remnant liver regeneration at 7 days, and 1, 2, 5, and 12 months postoperatively between the 2 groups (P = .585, .383, .507, .261, and .430, respectively). Regarding prognosis, there was no significant difference in overall and recurrence-free survival between the 2 groups (P = .065 and .166, respectively). CONCLUSION: Allogeneic transfusion during hepatectomy strongly affected remnant liver function in the early postoperative period; however, this was not related to the remnant liver regeneration volume. Despite that the allogeneic transfusion resulted in poorer postoperative laboratory test results and increased postoperative complication and mortality rates, it had no effect on the long-term prognosis.

Safety and Efficacy of Laparoscopic Liver Resection for Colorectal Liver Metastasis With Obesity.

INTRODUCTION: Laparoscopic liver resection (LLR) in obese patients has been reported to be particularly challenging owing to technical difficulties and various comorbidities. METHODS: The safety and efficacy outcomes in 314 patients who underwent laparoscopic or open nonanatomical liver resection for colorectal liver metastases (CRLM) were analyzed retrospectively with respect to the patients' body mass index (BMI) and visceral fat area (VFA). RESULTS: Two hundred and four patients underwent LLR, and 110 patients underwent open liver resection (OLR). The rate of conversion from LLR to OLR was 4.4%, with no significant difference between the BMI and VFA groups (P = .647 and .136, respectively). In addition, there were no significant differences in terms of operative time and estimated blood loss in LLR (P = .226 and .368; .772 and .489, respectively). The incidence of Clavien-Dindo grade IIIa or higher complications was not significantly different between the BMI and VFA groups of LLR (P = .877 and .726, respectively). In obese patients, the operative time and estimated blood loss were significantly shorter and lower, respectively, in LLR than in OLR (P = .003 and < .001; < .001 and < .001, respectively). There was a significant difference in the incidence of postoperative complications, organ/space surgical site infections, and postoperative bile leakage between the LLR and OLR groups (P = .017, < .001, and < .001, respectively). CONCLUSION: LLR for obese patients with CRLM can be performed safely using various surgical devices with no major difference in outcomes compared to those in nonobese patients. Moreover, LLR has better safety outcomes than OLR in obese patients.

Gastrointestinal Neurons Expressing HCN4 Regulate Retrograde Peristalsis.

Peristalsis is indispensable for physiological function of the gut. The enteric nervous system (ENS) plays an important role in regulating peristalsis. While the neural network regulating anterograde peristalsis, which migrates from the oral end to the anal end, is characterized to some extent, retrograde peristalsis remains unresolved with regards to its neural regulation. Using forward genetics in zebrafish, we reveal that a population of neurons expressing a hyperpolarization-activated nucleotide-gated channel HCN4 specifically regulates retrograde peristalsis. When HCN4 channels are blocked by an HCN channel inhibitor or morpholinos blocking the protein expression, retrograde peristalsis is specifically attenuated. Conversely, when HCN4(+) neurons expressing channelrhodopsin are activated by illumination, retrograde peristalsis is enhanced while anterograde peristalsis remains unchanged. We propose that HCN4(+) neurons in the ENS forward activating signals toward the oral end and simultaneously stimulate local circuits regulating the circular muscle.

The Relationship Between the Number of Ports and Surgical Outcomes in Laparoscopic Hepatectomy.

INTRODUCTION: Reduced port surgery (RPS) has been garnering interest as a novel minimally invasive surgery lately. AIM: The authors examined the relationship between the number of ports and surgical outcomes after laparoscopic hepatectomy (LH). MATERIALS AND METHODS: Between January 2012 and April 2019, 209 patients who underwent laparoscopic partial resection and lateral sectionectomy were retrospectively analyzed with respect to operative variables and surgical outcomes. Patients were divided into 5 groups by the number of ports used. Student's t test, the χ test, the likelihood-ratio test, Fisher exact test, or Mann-Whitney U test were used to analyze the data. RESULTS: Operative duration was significantly longer in patients with a larger number of ports than in those with a smaller number of ports. Chronological pain scores according to the visual analog scale (VAS) on postoperative days 1, 2, 4, and 7 were not associated with the number of ports and wound length in the umbilical region. The frequency of using additional analgesic agents was not significantly different between the groups. VAS scores and the number of additional analgesic agents used were smaller in patients in whom non-steroidal anti-inflammatory drugs were regularly administered postoperatively than in those in whom the drug was not regularly administered postoperatively. LH had a 3.4% complication rate (Clavien-Dindo classification >IIIA); however, this was not significantly different between the groups. CONCLUSIONS: No significant difference in postoperative pain was observed between RPS and conventional methods, although operative durations were shorter with RPS. However, RPS for LH may be associated with excellent cosmetic results compared with conventional methods.

Deepest and hottest hydrothermal activity in the Okinawa Trough: the Yokosuka site at Yaeyama Knoll.

Since the initial discovery of hydrothermal vents in 1977, these 'extreme' chemosynthetic systems have been a focus of interdisciplinary research. The Okinawa Trough (OT), located in the semi-enclosed East China Sea between the Eurasian continent and the Ryukyu arc, hosts more than 20 known vent sites but all within a relatively narrow depth range (600-1880 m). Depth is a significant factor in determining fluid temperature and chemistry, as well as biological composition. However, due to the narrow depth range of known sites, the actual influence of depth here has been poorly resolved. Here, the Yokosuka site (2190 m), the first OT vent exceeding 2000 m depth is reported. A highly active hydrothermal vent site centred around four active vent chimneys reaching 364°C in temperature, it is the hottest in the OT. Notable Cl depletion (130 mM) and both high H2 and CH4 concentrations (approx. 10 mM) probably result from subcritical phase separation and thermal decomposition of sedimentary organic matter. Microbiota and fauna were generally similar to other sites in the OT, although with some different characteristics. In terms of microbiota, the H2-rich vent fluids in Neuschwanstein chimney resulted in the dominance of hydrogenotrophic chemolithoautotrophs such as Thioreductor and Desulfobacterium. For fauna, the dominance of the deep-sea mussel Bathymodiolus aduloides is surprising given other nearby vent sites are usually dominated by B. platifrons and/or B. japonicus, and a sponge field in the periphery dominated by Poecilosclerida is unusual for OT vents. Our insights from the Yokosuka site implies that although the distribution of animal species may be linked to depth, the constraint is perhaps not water pressure and resulting chemical properties of the vent fluid but instead physical properties of the surrounding seawater. The potential significance of these preliminary results and prospect for future research on this unique site are discussed.