The World Organisation for Animal Health - current and potential roles in safe international trade of bees and other insects.

The World Organisation for Animal Health (WOAH, founded as OIE) is the recognised intergovernmental standard-setting organisation for animal health and welfare. The WOAH mandate is to support its members in the prevention of the spread of animal diseases of concern, as listed in the Terrestrial Animal Health Code (Terrestrial Code). Once a disease, infection or infestation is listed, national Veterinary Authorities have the obligation regularly to notify WOAH of the presence or absence of the listed disease. In regard to insects, the scope of the Terrestrial Code limits its recommendations to preserving the health of bees (species of the genus Apis, extended to the genus Bombus and to the stingless bees for one disease). However, it does not include standards to mitigate the potential animal health risks associated with the international trade of other insects. A description of the standard-setting process and a review of the history of the standards for bee health highlight the resources and requirements to expand the scope of the Terrestrial Code to include recommendations for animal health risk mitigation measures for the safety of international trade in insects. Any initiative to develop guidance on insect trade should include WOAH in its role as the sole global standard-setting organisation on animal health and welfare matters. This aligns with the WOAH commitment to a One Health approach.

L'Organisation mondiale de la santé animale (OMSA, fondée en tant qu'OIE) est l'organisation inter-gouvernementale reconnue pour l'élaboration de normes relatives à la santé et au bien-être des animaux. L'OMSA a pour mandat d'apporter un soutien à ses Membres afin de prévenir la propagation des maladies animales d'importance majeure listées dans le Code sanitaire pour les animaux terrestres (Code terrestre). Dès lors qu'une maladie, une infection ou une infestation figure sur cette liste, les Autorités vétérinaires ont l'obligation de notifier régulièrement à l'OMSA la présence ou l'absence de cette maladie sur leur territoire. S'agissant des insectes, le champ d'application du Code terrestre limite ses recommandations à la préservation de la santé des abeilles (espèces du genre Apis, avec l'inclusion du genre Bombus et des abeilles sans dard pour une maladie). Néanmoins, le Code terrestre ne contient pas de normes visant à atténuer les risques pour la santé animale associés aux échanges internationaux d'autres insectes. La description faite par les auteurs du processus d'élaboration des normes et leur aperçu rétrospectif de la mise au point des normes relatives à la santé des abeilles font ressortir les ressources et les conditions nécessaires pour élargir le champ d'application du Code terrestre afin d'y inclure des recommandations portant sur les mesures d'atténuation des risques pour la santé animale applicables à la sécurité sanitaire des échanges internationaux d'insectes. Toute initiative visant à fournir des orientations sur les échanges d'insectes devrait inclure l'OMSA dans son rôle d'unique organisation chargée de l'élaboration des normes internationales relatives à la santé animale et au bien-être des animaux. Cette exigence est en cohérence avec l'engagement de l'OMSA en faveur de l'approche Une seule santé.

La Organización Mundial de Sanidad Animal (OMSA, fundada como OIE) es la organización intergubernamental facultada para ejercer funciones normativas en materia de sanidad y bienestar de los animales. La OMSA tiene por mandato ayudar a sus miembros a prevenir la propagación de una serie de enfermedades animales de importancia, recogidas en el Código Sanitario para los Animales Terrestres (Código Terrestre) de la OMSA. La inclusión de una enfermedad, infección o infestación en la lista de la OMSA obliga a las autoridades veterinarias nacionales a dar cuenta periódicamente a la OMSA de la presencia o ausencia de esa patología en su territorio. Por lo que respecta a los insectos, en el Código Terrestre solo se formulan una serie de recomendaciones para proteger la salud de las abejas (categoría que corresponde a las especies del género Apis, extensible también al género Bombus y, en el caso de una enfermedad, a las abejas sin aguijón). El Código Terrestre, sin embargo, no contiene norma alguna destinada a mitigar los posibles riesgos zoosanitarios ligados al comercio internacional de otros insectos. Los autores describen el proceso normativo y repasan la historia de las normas relativas a la sanidad de las abejas, con lo que ponen de relieve los recursos y demás elementos necesarios para conferir mayor alcance al Código Terrestre incluyendo en él recomendaciones sobre medidas de mitigación del riesgo zoosanitario para un comercio seguro de insectos a escala internacional. Toda iniciativa encaminada a marcar pautas sobre el comercio de insectos debería incluir a la OMSA, única organización con potestad normativa mundial sobre temas de sanidad y bienestar de los animales, lo que además se encuadra en el compromiso de la OMSA con los planteamientos de «Una sola salud¼.

Magneto-optical spectroscopy on Weyl nodes for anomalous and topological Hall effects in chiral MnGe.

Physics of Weyl electrons has been attracting considerable interests and further accelerated by recent discoveries of giant anomalous Hall effect (AHE) and topological Hall effect (THE) in several magnetic systems including non-coplanar magnets with spin chirality or small-size skyrmions. These AHEs/THEs are often attributed to the intense Berry curvature generated around the Weyl nodes accompanied by band anti-crossings, yet the direct experimental evidence still remains elusive. Here, we demonstrate an essential role of the band anti-crossing for the giant AHE and THE in MnGe thin film by using the terahertz magneto-optical spectroscopy. The low-energy resonance structures around ~ 1.2 meV in the optical Hall conductivity show the enhanced AHE and THE, indicating the emergence of at least two distinct anti-crossings near the Fermi level. The theoretical analysis demonstrates that the competition of these resonances with opposite signs is a cause of the strong temperature and magnetic-field dependences of observed DC Hall conductivity. These results lead to the comprehensive understanding of the interplay among the transport phenomena, optical responses and electronic/spin structures.

Major hepatectomy with combined vascular resection for perihilar cholangiocarcinoma.

BACKGROUND: Hepatectomy with vascular resection (VR) for perihilar cholangiocarcinoma (PHCC) is a challenging procedure. However, only a few reports on this procedure have been published and its clinical significance has not been fully evaluated. METHODS: Patients undergoing surgical resection for PHCC from 2002-2017 were studied. The surgical outcomes of VR and non-VR groups were compared. RESULTS: Some 238 patients were included. VR was performed in 85 patients. The resected vessels were hepatic artery alone (31 patients), portal vein alone (37 patients) or both (17 patients). The morbidity rates were almost the same in the VR (49.4 per cent) and non-VR (43.8 per cent) groups (P = 0.404). The mortality rates of VR (3.5 per cent) and non-VR (3.3 per cent) were also comparable (P > 0.999). The median survival time (MST) was 45 months in the non-VR group and 36 months in VR group (P = 0.124). Among patients in whom tumour involvement was suspected on preoperative imaging and whose carbohydrate antigen 19-9 (CA19-9) value was 37 U/ml or less, MST in the VR group was significantly longer than that in the non-VR group (50 versus 34 months, P = 0.017). In contrast, when the CA19-9 value was greater than 37 U/ml, MST of the VR and non-VR groups was comparable (28 versus 29 months, P = 0.520). CONCLUSION: Hepatectomy with VR for PHCC can be performed in a highly specialized hepatobiliary centre with equivalent short- and long-term outcomes to hepatectomy without VR.

Utility of remnant liver volume for predicting posthepatectomy liver failure after hepatectomy with extrahepatic bile duct resection.

BACKGROUND: Hepatectomy with extrahepatic bile duct resection is associated with a high risk of posthepatectomy liver failure (PHLF). However, the utility of the remnant liver volume (RLV) in cholangiocarcinoma has not been studied intensively. METHODS: Patients who underwent major hepatectomy with extrahepatic bile duct resection between 2002 and 2018 were reviewed. The RLV was divided by body surface area (BSA) to normalize individual physical differences. Risk factors for clinically relevant PHLF were evaluated with special reference to the RLV/BSA. RESULTS: A total of 289 patients were included. The optimal cut-off value for RLV/BSA was determined to be 300 ml/m2. Thirty-two patients (11.1 per cent) developed PHLF. PHLF was more frequent in patients with an RLV/BSA below 300 ml/m2 than in those with a value of 300 ml/m2 or greater: 19 of 87 (22 per cent) versus 13 of 202 (6.4 per cent) (P < 0.001). In multivariable analysis, RLV/BSA below 300 ml/m2 (P = 0.013), future liver remnant plasma clearance rate of indocyanine green less than 0.075 (P = 0.031), and serum albumin level below 3.5 g/dl (P = 0.015) were identified as independent risk factors for PHLF. Based on these risk factors, patients were classified into three subgroups with low (no factors), moderate (1-2 factors), and high (3 factors) risk of PHLF, with PHLF rates of 1.8, 14.8 and 63 per cent respectively (P < 0.001). CONCLUSION: An RLV/BSA of 300 ml/m2 is a simple predictor of PHLF in patients undergoing hepatectomy with extrahepatic bile duct resection.

Giant magneto-optical responses in magnetic Weyl semimetal Co3Sn2S2.

The Weyl semimetal (WSM), which hosts pairs of Weyl points and accompanying Berry curvature in momentum space near Fermi level, is expected to exhibit novel electromagnetic phenomena. Although the large optical/electronic responses such as nonlinear optical effects and intrinsic anomalous Hall effect (AHE) have recently been demonstrated indeed, the conclusive evidence for their topological origins has remained elusive. Here, we report the gigantic magneto-optical (MO) response arising from the topological electronic structure with intense Berry curvature in magnetic WSM Co3Sn2S2. The low-energy MO spectroscopy and the first-principles calculation reveal that the interband transitions on the nodal rings connected to the Weyl points show the resonance of the optical Hall conductivity and give rise to the giant intrinsic AHE in dc limit. The terahertz Faraday and infrared Kerr rotations are found to be remarkably enhanced by these resonances with topological electronic structures, demonstrating the novel low-energy optical response inherent to the magnetic WSM.

Propagation dynamics of spin excitations along skyrmion strings.

Magnetic skyrmions, topological solitons characterized by a two-dimensional swirling spin texture, have recently attracted attention as stable particle-like objects. In a three-dimensional system, a skyrmion can extend in the third dimension forming a robust and flexible string structure, whose unique topology and symmetry are anticipated to host nontrivial functional responses. Here we experimentally demonstrate the coherent propagation of spin excitations along skyrmion strings for the chiral-lattice magnet Cu2OSeO3. We find that this propagation is directionally non-reciprocal and the degree of non-reciprocity, as well as group velocity and decay length, are strongly dependent on the character of the excitation modes. These spin excitations can propagate over a distance exceeding 50 µm, demonstrating the excellent long-range ordered nature of the skyrmion-string structure. Our combined experimental and theoretical analyses offer a comprehensive account of the propagation dynamics of skyrmion-string excitations and suggest the possibility of unidirectional information transfer along such topologically protected strings.

The tumor diameter cut-off for predicting microscopic intrahepatic metastasis of hepatocellular carcinoma patients without treatment history differs from that of hepatocellular carcinoma patients with a treatment history.

BACKGROUND AND AIM: Intrahepatic metastasis (IM) of hepatocellular carcinoma (HCC) occurs via vascular invasion; the tumor diameter that affects the risk of micro intra-hepatic metastasis (MIM) should be larger than that which affects the risk of micro vessel invasion (MVI). The aim of the present study was to determine the optimum tumor diameter cut-off value for predicting the presence of MIM in HCC patients without treatment history and HCC patients with a treatment history and to compare these diameters between cases of MVI and MIM. METHODS: This retrospective study included 621 patients without macroscopic vessel invasion or intrahepatic metastasis on preoperative imaging who underwent hepatectomy. The cut-off tumor diameter for predicting the presence of MIM was determined by a receiver operating characteristic curves analysis. RESULTS: The optimum cut-off value for predicting the presence of MIM in HCC patients without treatment history was 43 mm. In contrast, the optimum cut-off value for predicting the presence of MIM in HCC patients with a treatment history was 20 mm. Among 46 HCC patients with MIM without treatment history, there were 20 patients with MIM without MVI who were considered to have potential multi-centric (MC) tumors rather than IM. The cumulative overall survival rates in patients with MIM without MVI (potential MC) was significantly better than that in patients with both MIM and MVI (P = 0.022). CONCLUSIONS: The tumor diameter cut-off value for predicting MIM differed between HCC patients without treatment history and with a treatment history and slightly smaller than those for predicting MVI beyond our expectation.

Prognostic role of the length of tumour-vein contact at the portal-superior mesenteric vein in patients having surgery for pancreatic cancer.

BACKGROUND: The length of tumour-vein contact between the portal-superior mesenteric vein (PV/SMV) and pancreatic head cancer, and its relationship to prognosis in patients undergoing pancreatic surgery, remains controversial. METHODS: Patients diagnosed with pancreatic head cancer who were eligible for pancreatoduodenectomy between October 2002 and December 2016 were analysed. The PV/SMV contact was assessed retrospectively on CT. Using the minimum P value approach based on overall survival after surgery, the optimal cut-off value for tumour-vein contact length was identified. RESULTS: Among 491 patients included, 462 underwent pancreatoduodenectomy for pancreatic head cancer. PV/SMV contact with the tumour was detected on preoperative CT in 248 patients (53·7 per cent). Overall survival of patients with PV/SMV contact exceeding 20 mm was significantly worse than that of patients with a contact length of 20 mm or less (median survival time (MST) 23·3 versus 39·3 months; P = 0·012). Multivariable analysis identified PV/SMV contact longer than 20 mm as an independent predictor of poor survival, whereas PV/SMV contact greater than 180° was not a predictive factor. Among patients with a PV/SMV contact length exceeding 20 mm on pretreatment CT, those receiving neoadjuvant therapy had significantly better overall survival than patients who had upfront surgery (MST not reached versus 21·6 months; P = 0·002). CONCLUSION: The length of PV/SMV contact predicts survival, and may be used to suggest a role for neoadjuvant therapy to improve prognosis.

ANTECEDENTES: El valor pronóstico de la longitud del contacto del tumor de la cabeza pancreática con las venas porta y mesentérica superior (portal-superior mesenteric vein, PV/SMV) en los pacientes sometidos a cirugía pancreática sigue siendo un tema controvertido. MÉTODOS: Se analizaron los pacientes diagnosticados de un cáncer de la cabeza pancreática a los que se realizó una duodenopancreatectomía cefálica entre octubre de 2002 y diciembre de 2016. El contacto tumoral con la PV/SMV se evaluó de forma retrospectiva mediante tomografía computarizada (TC). Se identificó el valor de corte óptimo para la longitud del contacto tumoral con la PV/SMV, utilizando el valor mínimo de la P basado en la supervivencia global (overall survival, OS) después de la cirugía. RESULTADOS: De 491 pacientes incluidos, en 462 pacientes se realizó una duodenopancreatectomía cefálica por cáncer de la cabeza de páncreas. En la TC preoperatoria, se detectó contacto tumoral con la PV/SMV en 248 (53,7%) pacientes. La OS de los pacientes en los que el contacto del tumor con la PV/SMV fue > 20 mm fue significativamente peor que en aquellos cuyo contacto fue ≤ 20 mm (mediana de supervivencia (median survival time, MST) 23,3 versus 39,3 meses; P = 0,012). En un análisis multivariado se identificó el contacto tumoral-PV/SMV > 20 mm como un factor independiente predictor de mala supervivencia, pero el contacto tumor-PV/SMV > 180° no fue un factor pronóstico. En los pacientes en los que el contacto tumor-PV/SMV fue > 20 mm en el TC preoperatorio, la OS en aquellos que recibieron tratamiento neoadyuvante fue significativamente mejor en comparación con los pacientes tratados directamente con cirugía (MST, no alcanzada versus 21,6 meses, P = 0,002). Conclusión La longitud del contacto tumoral con la PV/SMV predice la supervivencia, por lo cual dicha longitud podría jugar un papel en la indicación de tratamiento neoadyuvante para mejorar el pronóstico.

Microwave Directional Dichroism Resonant with Spin Excitations in the Polar Ferromagnet GaV_{4}S_{8}.

We have investigated the directional dichroism of magnetic resonance spectra in the polar ferromagnet GaV_{4}S_{8}. While four types of structural domains are energetically degenerated under a zero field, the magnetic resonance for each domain is well separated by applying magnetic fields due to uniaxial magnetic anisotropy. Consequently, a directional dichroism as large as 20% is clearly observed without domain cancellation. The present observation therefore demonstrates that not only magnetoelectric monodomain crystals but also magnetoelectric multidomain specimens can be used to realize microwave (optical) diodes owing to the lack of inversion domains.

Propensity score-matched comparison of non-anatomical resection and radiofrequency ablation for hepatocellular carcinoma in patients with up to three tumours, each measuring up to 3 cm in diameter.

BACKGROUND: Non-anatomical liver resection (NAR) and radiofrequency ablation (RFA) are treatment options for early-stage hepatocellular carcinoma (HCC). The aim was to compare the outcomes of NAR and RFA for HCC in patients with three or fewer tumour nodules, each measuring not more than 3 cm in maximum diameter. METHODS: Eligible patients undergoing NAR or RFA with curative intent between September 2002 and December 2014 were identified. A propensity score-matching analysis was performed to reduce bias, and outcomes in these patients were analysed. RESULTS: From a total of 199 patients, 1:1 propensity score matching identified 70 matched pairs. Patients having NAR had a longer hospital stay (median 10 days versus 4 days for those who had RFA; P < 0·001) and a higher morbidity rate (24 versus 10 per cent respectively; P = 0·042). Patients who had NAR had slightly better recurrence-free survival but this failed to reach statistical significance in univariable analysis (P = 0·064). There was no significant difference in overall survival between the two groups (P = 0·475). RFA was identified as an independent risk factor for recurrence-free survival (hazard ratio (HR) 1·57; P = 0·041) in multivariable analysis. Local recurrence was significantly more common in patients receiving RFA (23 versus 1 per cent; P < 0·001). CONCLUSION: RFA was an independent risk factor for shorter recurrence-free survival, with a significantly higher local recurrence rate than NAR. Despite these differences, overall survival was not affected.

Impact of Patient Age on the Postoperative Survival in Pancreatic Head Cancer.

BACKGROUND: Some reports have stated that pancreatoduodenectomy for elderly patients have comparable morbidity and mortality to that of young patients. However, the long-term outcomes of these patients have not been fully evaluated, especially for pancreatic head cancer. METHODS: A total of 227 patients who underwent pancreatoduodenectomy for pancreatic head cancer between 2007 and 2014 were included. They were stratified according to age: young (<70 years), elderly (70 to <80 years), and very elderly (≥80 years). The short- and long-term outcomes were evaluated. RESULTS: There were no significant differences in terms of morbidity among the three groups. The median disease-free survival times were 15 months in the young, 11 months in the elderly, and 7 months in the very elderly. The disease-free survival of the young patients was significantly better than that in both the elderly and the very elderly (p = 0.012 and p = 0.016). The median overall survival times were 30 months in the young, 20 months in the elderly, and 14 months in the very elderly. The overall survival of the young patients was significantly better than that in both the elderly and the very elderly (p = 0.007 and p < 0.001). The difference was marginal between the elderly and the very elderly (p = 0.053). Multivariate analysis revealed that lymph node metastasis (p < 0.001), age ≥80 years (p = 0.013), lack of adjuvant chemotherapy (p = 0.003), blood transfusion (p = 0.015), and CA 19-9 ≥300 U/ml (p = 0.040) were significant prognostic factors. CONCLUSIONS: Patient age influenced the survival after pancreatoduodenectomy for pancreatic cancer.

Treatment of cervical pregnancy with ultrasound-guided local methotrexate injection.

OBJECTIVES: Cervical pregnancy (CP) is a rare type of ectopic pregnancy. While methotrexate (MTX) is generally the first-line method of choice for clinically stable women, there is still no consensus on the most appropriate treatment for this abnormal pregnancy. The aim of this study was to investigate the efficacy of a single local MTX injection under transvaginal ultrasound guidance for the initial treatment of CP and to assess post-treatment fertility. METHODS: We reviewed retrospectively 15 patients with CP treated with local MTX injection under transvaginal ultrasound guidance. In all patients, the serum human chorionic gonadotropin (hCG) levels were monitored and the gestational sac was evaluated using ultrasonography after treatment. Magnetic resonance imaging (MRI) was performed as necessary. We evaluated the patients' clinical characteristics and clinical course after treatment, the efficacy of the treatment and the post-treatment fertility in patients desiring subsequent pregnancy. RESULTS: The median estimated gestational age at the time of MTX injection was 6 + 2 (range, 5 + 2 to 11 + 0) weeks. All 15 patients were treated successfully, without the need for blood transfusion or surgical procedures; however, three patients required an additional local MTX injection due to a poor decline in serum hCG level following the initial injection, while one patient required uterine artery embolization due to persistent vaginal bleeding and an enlarging gestational sac with blood vessels visible on contrast-enhanced MRI. The mean time following initial MTX injection for hCG normalization was 43.8 (95% CI, 33.3-54.3) days and for resumption of menses was 68.4 (95% CI, 51.9-84.9) days. Seven of the 10 women desiring subsequent pregnancy following treatment had uneventful pregnancy, one became pregnant but miscarried spontaneously at 8 weeks of gestation, one was treated by laparoscopic surgery after diagnosis of a tubal pregnancy and one did not conceive. CONCLUSIONS: A single, ultrasound-guided, local MTX injection is apparently effective for the treatment of CP without the need for concomitant procedures or surgical intervention. Furthermore, this conservative technique both preserves fertility and allows for the possibility of subsequent uneventful pregnancy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Indications for major hepatectomy and combined procedures for advanced gallbladder cancer.

BACKGROUND: The clinical impact of major hepatectomy for advanced gallbladder cancer is currently unclear. METHODS: Patients who underwent resection for stage II, III or IV gallbladder cancer were enrolled. The surgical outcomes of patients who underwent major hepatectomy were compared with those of patients treated with minor hepatectomy and those with unresectable gallbladder cancer. The clinical impact of major hepatectomy and combined advanced procedures such as portal vein resection or pancreatoduodenectomy for advanced gallbladder cancer were evaluated. RESULTS: A total of 96 patients were enrolled; 29 patients underwent major and 67 had minor hepatectomy. The overall morbidity rate was higher in the major hepatectomy group (55 versus 27 per cent; P = 0·022). There were no deaths after major hepatectomy. Overall survival was better in the major hepatectomy group than in the group of 15 patients with unresectable disease (median survival 17·7 versus 11·4 months; P = 0·003). In a subgroup analysis of the major hepatectomy group, liver metastasis (P = 0·038) and hepatic arterial invasion (P = 0·017) were independently associated with overall survival. Overall survival in patients with liver metastasis (P = 0·572) or hepatic arterial invasion (P = 0·776) was comparable with that in the unresectable group. However, overall survival among patients with lymph node metastasis (P = 0·062) or following portal vein resection (P = 0·054) or pancreatoduodenectomy (P = 0·011) was better than in the unresectable group. CONCLUSION: Major hepatectomy combined with portal vein resection or pancreatoduodenectomy, if necessary, may be considered in the treatment of advanced gallbladder cancer, especially in selected patients without liver metastasis or hepatic arterial invasion.

Impact of Subnormothermic Machine Perfusion Preservation in Severely Steatotic Rat Livers: A Detailed Assessment in an Isolated Setting.

The current drastic shortage of donor organs has led to acceptance of extended-criteria donors for transplantation, despite higher risk of primary nonfunction. Here, we report the impact of subnormothermic machine perfusion (SMP) preservation on the protection of >50% macrosteatotic livers. Dietary hepatic steatosis was induced in Wistar rats via 2-day fasting and subsequent 3-day re-feeding with a fat-free, carbohydrate-rich diet. This protocol induces 50-60% macrovesicular steatosis, which should be discarded when preserved via cold storage (CS). The fatty livers were retrieved and preserved for 4 h using either CS in histidine-tryptophan-ketoglutarate or SMP in polysol solution. Graft functional integrity was evaluated via oxygenated ex vivo reperfusion for 2 h at 37°C. SMP resulted in significant reductions in not only parenchymal alanine aminotransferase (p < 0.001), but also mitochondrial glutamate dehydrogenase (p < 0.001) enzyme release. Moreover, portal venous pressure (p = 0.047), tissue adenosine triphosphate (p = 0.001), bile production (p < 0.001), high-mobility group box protein-1 (p < 0.001), lipid peroxidation, and tissue glutathione were all significantly improved by SMP. Electron microscopy revealed that SMP alleviated deleterious alterations of sinusoidal microvasculature and hepatocellular mitochondria, both of which are characteristic disadvantages associated with steatosis. SMP could protect 50-60% macrosteatotic livers from preservation/reperfusion injury, and may thus represent a new means for expanding available donor pools.

Transition to and from the skyrmion lattice phase by electric fields in a magnetoelectric compound.

Dissipation-less electric control of magnetic state variable is an important target of contemporary spintronics. The non-volatile control of magnetic skyrmions, nanometre-sized spin-swirling objects, with electric fields may exemplify this goal. The skyrmion-hosting magnetoelectric chiral magnet Cu2OSeO3 provides a unique platform for the implementation of such control; however, the hysteresis that accompanies the first-order transition associated with the skyrmion phase is negligibly narrow in practice. Here we demonstrate another method that functions irrespective of the transition boundary. Combination of magnetic-susceptibility measurements and microwave spectroscopy reveals that although the metastable skyrmion lattice is normally hidden behind a more thermodynamically stable conical phase, it emerges under electric fields and persists down to the lowest temperature. Once created, this metastable skyrmion lattice remains without electric fields, establishing a bistability distinct from the transition hysteresis. This bistability thus enables non-volatile electric-field control of the skyrmion lattice even in temperature/magnetic-field regions far from the transition boundary.

Neutrophil to lymphocyte ratio as an indicator of the malignant behaviour of hepatocellular carcinoma.

BACKGROUND: The preoperative serum neutrophil to lymphocyte ratio (NLR) has been associated with survival in patients with hepatocellular carcinoma (HCC). However, it is still unclear what the NLR reflects precisely. This study aimed to elucidate the relationship between the NLR and TNM stage, and the role of NLR as a prognostic factor after liver resection for HCC. METHODS: This retrospective study enrolled patients who underwent liver resection as initial treatment for HCC. The best cut-off value of serum NLR was determined, and overall survival was compared among patients grouped according to TNM stage (I, II and III). RESULTS: The best cut-off value for NLR was 2·8. A high preoperative NLR was more frequently associated with poor overall survival than a low preoperative NLR after resection for TNM stage I tumours (5-year survival 45·0 versus 76·4 per cent, P < 0·001), but not stage II (P = 0·283) or stage III (P = 0·155) tumours. Among patients with TNM stage I disease, the proportion of patients with extrahepatic recurrence was greater in the group with a high preoperative NLR than in the low-NLR group (P = 0·006). In multivariable analysis, preoperative NLR was the strongest independent prognostic risk factor for overall survival in TNM stage I (hazard ratio 2·69, 95 per cent c.i. 1·57 to 4·59; P < 0·001). CONCLUSION: Preoperative NLR was an important prognostic factor for TNM stage I HCC after liver resection with curative intent. These results suggest that the NLR may reflect the malignant potential of HCC.

Impact of bacterial contamination of the abdominal cavity during pancreaticoduodenectomy on surgical-site infection.

BACKGROUND: Several risk factors for complications after pancreaticoduodenectomy have been reported. However, the impact of intraoperative bacterial contamination on surgical outcome after pancreaticoduodenectomy has not been examined in depth. METHODS: This retrospective study included patients who underwent pancreaticoduodenectomy and peritoneal lavage using 7000 ml saline between July 2012 and May 2014. The lavage fluid was subjected to bacterial culture examination. The influence of a positive bacterial culture on surgical-site infection (SSI) and postoperative course was evaluated. Risk factors for positive bacterial cultures were also evaluated. RESULTS: Forty-six (21.1 per cent) of 218 enrolled patients had a positive bacterial culture of the lavage fluid. Incisional SSI developed in 26 (57 per cent) of these 46 patients and in 13 (7.6 per cent) of 172 patients with a negative lavage culture (P < 0.001). Organ/space SSI developed in 32 patients with a positive lavage culture (70 per cent) and in 43 of those with a negative culture (25.0 per cent) (P < 0.001). Grade B/C pancreatic fistula was observed in 22 (48 per cent) and 48 (27.9 per cent) respectively of patients with positive and negative lavage cultures (P = 0.010). Postoperative hospital stay was longer in patients with a positive lavage culture (28 days versus 21 days in patients with a negative culture; P = 0.028). Multivariable analysis revealed that internal biliary drainage, combined colectomy and a longer duration of surgery were significant risk factors for positive bacterial culture of the lavage fluid. CONCLUSION: Intraoperative bacterial contamination has an adverse impact on the development of SSI and grade B/C pancreatic fistula following pancreaticoduodenectomy.

Microwave Magnetochiral Dichroism in the Chiral-Lattice Magnet Cu_{2}OSeO_{3}.

Through broadband microwave spectroscopy in Faraday geometry, we observe distinct absorption spectra accompanying magnetoelectric (ME) resonance for oppositely propagating microwaves, i.e., directional dichroism, in the multiferroic chiral-lattice magnet Cu_{2}OSeO_{3}. The magnitude of the directional dichroism critically depends on the magnetic-field direction. Such behavior is well accounted for by considering the relative direction of the oscillating electric polarizations induced via the ME effect with respect to microwave electric fields. Directional dichroism in a system with an arbitrary form of ME coupling can be also discussed in the same manner.