Background
Bismuth type IV perihilar cholangiocarcinoma has traditionally been categorized as unresectable disease. The aim of this study was to review experience with a resection‐based strategy in ...patients who have type IV perihilar cholangiocarcinoma.
Methods
Medical records of consecutive patients with a diagnosis of type IV perihilar cholangiocarcinoma between 2006 and 2015 were reviewed retrospectively. Primary outcomes assessed were surgical results and long‐term survival.
Results
Of the 332 patients with type IV tumour, 216 (65·1 per cent) underwent resection. Left hepatic trisectionectomy was the most common procedure (112 patients). Combined vascular resection was performed in 131 patients. Median duration of operation was 607 (range 356–1045) min, and blood loss was 1357 (209–10 349) ml. Complications of Clavien–Dindo grade III or more developed in 90 patients (41·7 per cent) and four (1·9 per cent) died from complications within 90 days. Survival rates were better for the 216 patients whose tumours were resected than for the 116 patients with unresected tumours (32·8 versus 1·5 per cent at 5 years; P < 0·001). Patients with pN0 M0 disease after resection had a favourable 5‐year survival rate of 53 per cent. Percutaneous transhepatic biliary drainage, blood transfusion, lymph node metastasis and distant metastasis were identified as independent negative prognostic factors for survival.
Conclusion
Although resection for type IV tumour is technically demanding with high morbidity, it can be performed with low mortality and offers better survival probability in selected patients.
Irresectability revisited
The purpose of this study was to clarify the time course of the viscoelasticity of gastrocnemius medialis muscle and tendon after stretching. In 11 male participants, displacement of the myotendinous ...junction on the gastrocnemius medialis muscle was measured ultrasonographically during the passive dorsiflexion test, in which the ankle was passively dorsiflexed at a speed of 1°/s to the end of the range of motion (ROM). Passive torque, representing resistance to stretch, was also measured using an isokinetic dynamometer. On five different days, passive dorsiflexion tests were performed before and 0, 15, 30, 60 or 90 min after stretching, which consisted of dorsiflexion to end ROM and holding that position for 1 min, five times. As a result, end ROM was significantly increased at 0, 15 and 30 min (P<0.05 each) after stretching as compared with each previous value. Passive torque at end ROM was also significantly increased after stretching. Although the stiffness of the muscle–tendon unit was significantly decreased immediately after stretching (P<0.05), this shift recovered within 15 min. These results showed that the retention time of the effect of stretching on viscoelasticity of the muscle–tendon unit was shorter than the retention time of the effect of stretching on end ROM.
Background
Traditional classifications for open liver resection are not always associated with surgical complexity and postoperative morbidity. The aim of this study was to test whether a three‐level ...classification for stratifying surgical complexity based on surgical and postoperative outcomes, originally devised for laparoscopic liver resection, is superior to classifications based on a previously reported survey for stratifying surgical complexity of open liver resections, minor/major nomenclature or number of resected segments.
Methods
Patients undergoing a first open liver resection without simultaneous procedures at MD Anderson Cancer Center (Houston cohort) or the University of Tokyo (Tokyo cohort) were studied. Surgical and postoperative outcomes were compared among three grades: I (wedge resection for anterolateral or posterosuperior segment and left lateral sectionectomy); II (anterolateral segmentectomy and left hepatectomy); III (posterosuperior segmentectomy, right posterior sectionectomy, right hepatectomy, central hepatectomy and extended left/right hepatectomy).
Results
In both the Houston (1878 patients) and Tokyo (1202) cohorts, duration of operation, estimated blood loss and comprehensive complication index score differed between the three grades (all P < 0·050) and increased in stepwise fashion from grades I to III (all P < 0·001). Left hepatectomy was associated with better surgical and postoperative outcomes than right hepatectomy, extended right hepatectomy and right posterior sectionectomy, although these four procedures were categorized as being of medium complexity in the survey‐based classification. Surgical outcomes of minor open liver resections also differed between the three grades (all P < 0·050). For duration of operation and blood loss, the area under the curve was higher for the three‐level classification than for the minor/major or segment‐based classification.
Conclusion
The three‐level classification may be useful in studies analysing open liver resection at Western and Eastern centres.
Antecedentes
Las clasificaciones tradicionales de la resección hepática abierta (open liver resection, OLR) por número de segmentos resecados, no siempre se asocian con la complejidad quirúrgica y la morbilidad postoperatoria. El objetivo de este estudio fue comprobar si una clasificación de 3 niveles para estratificar la complejidad quirúrgica en función de los resultados quirúrgicos y postoperatorios, ideada originalmente para la resección hepática laparoscópica, es superior a las clasificaciones basadas en una encuesta descrita previamente para estratificar la complejidad quirúrgica de los procedimientos de OLR, nomenclatura menor/mayor, o número de segmentos resecados.
Métodos
Se estudiaron pacientes sometidos a una primera OLR sin otros procedimientos quirúrgicos concomitantes en el hospital MD Anderson (cohorte de Houston) o en la Universidad de Tokio (cohorte de Tokio). Se compararon los resultados quirúrgicos y postoperatorios entre 3 grados: I (resección limitada para el segmento anterolateral o posterosuperior y seccionectomía izquierda); II (segmentectomía anterolateral y hepatectomía izquierda); III (segmentectomía posterosuperior, seccionectomía posterior derecha, hepatectomía derecha, hepatectomía central y hepatectomía ampliada izquierda/derecha).
Resultados
En ambas cohortes de Houston (n = 1.878) y Tokio (n = 1.202), el tiempo operatorio, las pérdidas estimadas de sangre, y el índice de complejidad integral (comprehensive complication index) variaba en los 3 grados (todos P < 0,05) y aumentaba paso a paso desde los grados I a III (todos P < 0,05). La hepatectomía izquierda se asociaba con mejores resultados quirúrgicos y postoperatorios que la hepatectomía derecha, hepatectomía derecha ampliada, y seccionectomía posterior derecha, aunque estos cuatro procedimientos fueron categorizados como de complejidad intermedia en la clasificación basada en la encuesta. Los resultados quirúrgicos de las OLRs menores también variaron en los 3 grados (todos P < 0,05). Para el tiempo operatorio y la pérdida sanguínea, el área bajo la curva fue mayor para la clasificación de 3 niveles en el estudio actual, que para la clasificación menor/mayor o la clasificación basada en los segmentos.
Conclusión
La clasificación en 3 niveles puede ser útil en estudios que analizan las resecciones hepáticas abiertas en centros occidentales y orientales.
In cohorts from the USA and Japan, the three‐level classification, originally reported for the complexity of laparoscopic liver resection, effectively stratified 11 different open liver resection procedures regarding surgical complexity and postoperative morbidity, and was superior to minor/major‐ or segment‐based classifications in stratifying procedures by surgical complexity.
Maybe useful in stratifying liver surgery
The purpose of this study was to clarify the temporal course of stiffness in the muscle-tendon unit after stretching. In 11 male participants, displacement of the myotendinous junction on the ...gastrocnemius medialis muscle was measured ultrasonographically during the passive-dorsiflexion test, with the ankle was passively dorsiflexed at 1 °/s to the end of the range of motion. Passive torque, representing resistance to stretch, was also measured using an isokinetic dynamometer. On 4 different days, passive-dorsiflexion tests were performed before and immediately, 5, 10 or 15 min after stretching, which comprised dorsiflexion to end range of motion and holding that position for 1 min, 5 times. As a result, end range of motion and passive torque at end range of motion were significantly increased after stretching (P<0.05) as compared with each previous value. Although stiffness of the muscle-tendon unit was significantly decreased immediately and 5 min after stretching (P<0.05), this change recovered within 10 min. These results suggest that static stretching for 5 min results in significantly increased range of motion over 30 min, but significant decreases in stiffness of the muscle-tendon unit returned to baseline levels within 5-10 min.
The purpose of this study was to identify changes in ankle range of motion and passive mechanical properties of the muscle-tendon unit after dynamic stretching. 12 healthy subjects participated in ...this study. Displacement of the muscle-tendon junction was measured using ultrasonography while the ankle was passively dorsiflexed at 1°/sec to its maximal dorsiflexion angle. Passive torque was also measured using an isokinetic dynamometer. Measurements were conducted pre-intervention, immediately after the intervention and 5, 10, 15 and 30 min post-intervention. The dynamic stretching consisted of four 30-s periods of ankle dorsiflexion and plantarflexion. Ankle range of motion was significantly increased immediately (from 18.3±1.8° to 21.4±1.7°) and 10 min (20.9±1.9°) after dynamic stretching, but this change disappeared within 15 min. However, stiffness of the muscle-tendon unit and displacement of the muscle-tendon junction at the submaximal dorsiflexion angle did not differ between the experimental conditions. These results demonstrate that dynamic stretching by contracting an antagonist muscle group increases ankle range of motion temporarily without changing the passive mechanical properties of the muscle-tendon unit. The increased range of motion of the ankle after dynamic stretching might be caused by enhanced stretch tolerance.
The Yes-associated protein (YAP) is a transcriptional factor involved in tissue development and tumorigenesis. Although YAP has been recognized as a key element of the Hippo signaling pathway, the ...mechanisms that regulate YAP activities remain to be fully characterized. In this study, we demonstrate that the non-receptor type protein tyrosine phosphatase 14 (PTPN14) functions as a negative regulator of YAP. We show that YAP forms a protein complex with PTPN14 through the WW domains of YAP and the PPXY motifs of PTPN14. In addition, PTPN14 inhibits YAP-mediated transcriptional activities. Knockdown of YAP sensitizes cancer cells to various anti-cancer agents, such as cisplatin, the EGFR tyrosine kinase inhibitor erlotinib and the small-molecule antagonist of survivin, S12. YAP-targeted modalities may be used in combination with other cancer drugs to achieve maximal therapeutic effects.
Background
Little is known about the effect of additional resection for a frozen‐section‐positive distal bile duct margin (DM) in perihilar cholangiocarcinoma.
Methods
Patients who underwent surgical ...resection for perihilar cholangiocarcinoma between 2001 and 2015 were analysed retrospectively, focusing on the DM.
Results
Of 558 consecutive patients who underwent frozen‐section examination for a DM, 74 (13·3 per cent) had a frozen‐section‐positive DM with invasive cancer or carcinoma in situ. Eventually, 53 patients underwent additional resection (bile duct resection in 44 and pancreatoduodenectomy in 9), whereas the remaining 21 patients did not. Ultimately, R0 resection was achieved in 30 of the 53 patients (57 per cent). No patient who underwent additional resection died from surgical complications. The 44 patients with additional bile duct resection had a 5‐year overall survival rate of 31 per cent. Overall survival of the nine patients who had pancreatoduodenectomy was better, with a 10‐year rate of 67 per cent. Survival of the 21 patients without additional resection was dismal: all died within 5 years. Multivariable analyses identified nodal status and additional resection as independent prognostic factors (lymph node metastasis: hazard ratio (HR) 2·26, 95 per cent c.i. 1·26 to 4·07; bile duct resection versus no additional resection: HR 0·32, 0·17 to 0·60; pancreatoduodenectomy versus no additional resection: HR 0·08, 0·02 to 0·29).
Conclusion
Additional resection for frozen‐section‐positive DM in perihilar cholangiocarcinoma frequently yields R0 margins. It offers a better chance of long‐term survival, and thus should be performed in carefully selected patients.
The clinical value of additional resection for frozen‐section‐positive distal bile duct margin was evaluated in patients who underwent resection for perihilar cholangiocarcinoma. Additional bile duct resection or pancreatoduodenectomy frequently yields R0 margins, offers a better chance of long‐term survival, and thus should be performed in carefully selected patients.
Additional resection adds value
Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive neuronal loss and cognitive decline. Oligomeric amyloid β (oAβ) is involved in the pathogenesis of AD by ...affecting synaptic plasticity and inhibiting long-term potentiation. Although several lines of evidence suggests that microglia, the resident immune cells in the central nervous system (CNS), are neurotoxic in the development of AD, the mechanism whether or how oAβ induces microglial neurotoxicity remains unknown. Here, we show that oAβ promotes the processing of pro-interleukin (IL)-1β into mature IL-1β in microglia, which then enhances microglial neurotoxicity. The processing is induced by an increase in activity of caspase-1 and NOD-like receptor family, pyrin domain containing 3 (NLRP3) via mitochondrial reactive oxygen species (ROS) and partially via NADPH oxidase-induced ROS. The caspase-1 inhibitor Z-YVAD-FMK inhibits the processing of IL-1β, and attenuates microglial neurotoxicity. Our results indicate that microglia can be activated by oAβ to induce neuroinflammation through processing of IL-1β, a pro-inflammatory cytokine, in AD.
This article reports the results of X-ray studies of the extended TeV γ-ray source VER J2019+368. Suzaku observations conducted to examine properties of the X-ray pulsar wind nebula (PWN) around PSR ...J2021+3651 revealed that the western region of the X-ray PWN has a source extent of with the major axis oriented to that of the TeV emission. The PWN-west spectrum was closely fitted by a power law for absorption at and a photon index of , with no obvious change in the index within the X-ray PWN. The measured X-ray absorption indicates that the distance to the source is much less than the inferred by radio data. Aside from the PWN, no extended emission was observed around PSR J2021+3651 even by Suzaku. Archival data from the XMM-Newton were also analyzed to complement the Suzaku observations, indicating that the eastern region of the X-ray PWN has a similar spectrum ( and ) and source extent up to at least along the major axis. The lack of significant change in the photon index and the source extent in X-ray are used to constrain the advection velocity or the diffusion coefficient for accelerated X-ray-producing electrons. A mean magnetic field of is required to account for the measured X-ray spectrum and reported TeV γ-ray spectrum. A model calculation of synchrotron radiation and inverse Compton scattering was able to explain of the reported TeV flux, indicating that the X-ray PWN is a major contributor of VER J2019+368.
Hayabusa2 was launched on 3 December 2014 on an H-IIA launch vehicle from the Tanegashima Space Center, and is, at the time of writing, cruising toward asteroid 162137 Ryugu (
1999
JU
3
). After ...reaching the asteroid, it will stay for about 1.5 years to observe the asteroid and collect surface material samples.
The light detection and ranging (LIDAR) laser altimeter on Hayabusa2 has a wide dynamic range, from 25 km to 30 m, because the LIDAR is used as a navigation sensor for rendezvous, approach, and touchdown procedures. Since it was designed for use in planetary explorers, its weight is a low 3.5 kg. The LIDAR can serve not only as a navigation sensor, but also as observation equipment for estimating the asteroid’s topography, gravity and surface reflectivity (albedo). Since Hayabusa2 had a development schedule of just three years from the start of the project to launch, minimizing development time was a particular concern. A key to shortening the development period of Hayabusa2’s LIDAR system was heritage technology from Hayabusa’s LIDAR and the SELENE lunar explorer’s LALT laser altimeter.
Given that the main role of Hayabusa2’s LIDAR is to serve as a navigation sensor, we discuss its development from an engineering viewpoint. However, detailed information about instrument development and test results is also important for scientific analysis of LIDAR data and for future laser altimetry in lunar and planetary exploration. Here we describe lessons learned from the Hayabusa LIDAR, as well as Hayabusa2’s hardware, new technologies and system designs based on it, and flight model evaluation results. The monolithic laser used in the laser module is a characteristic technology of this LIDAR. It was developed to solve issues with low-temperature storage that were problematic when developing the LIDAR system for the first Hayabusa mission. The new module not only solves such problems but also improves reliability and miniaturization by reducing the number of parts.
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