How Topographic Diffusion-Weighted Imaging Patterns can Predict the Potential Embolic Source.

PURPOSE: To develop an imaging prediction model for patients with embolic stroke of undetermined source (ESUS), we investigated the association of topographic diffusion-weighted imaging (DWI) patterns with potential embolic sources (PES) identified by transesophageal echocardiography. METHODS: From a total of 992 consecutive patients with embolic stroke, 366 patients with the ESUS group were selected. ESUS was defined as no atrial fibrillation (Af) within 24h from admission and no PES after general examination. Clinical variables include age (> 80years, 70-80 years), sex, vascular risk factors and left atrial diameter > 4 cm. Age, sex and vascular risk factors adjusted odds ratio of each DWI for the different PESs were calculated. DWI was determined based on the arterial territories. Middle cerebral arteries were divided into 4 segments, i.e., M1-M4. Moreover, M2 segments were subdivided into superior and inferior branches. RESULTS: The 366 patients consisted of 168 with paroxysmal Af (pAf), 77 with paradoxical embolism, 71 with aortic embolism and 50 with undetermined embolism after transesophageal echocardiography. The variables adjusted odds ratio (OR) of internal carotid artery (OR: 12.1, p = 0.037), M1 (4.2, p = 0.001), inferior M2 (7.5, p = 0.0041) and multiple cortical branches (12.6, p < 0.0001) were significantly higher in patients with pAf. Striatocapsular infarction (12.5, p < 0.0001) and posterior inferior cerebellar artery infarcts (3.6, p = 0.018) were significantly associated with paradoxical embolism. Clinical variables adjusted OR of multiple small scattered infarcts (8.3, p < 0.0001) were significantly higher in patients with aortic embolism. CONCLUSION: The associations of DWI with different PES have their distinctive characteristics and DWI along with clinical variables may help predict PES in patients with ESUS.

Impact of hospital environmental cleaning with a potassium peroxymonosulphate-based environmental disinfectant and antimicrobial stewardship on the reduction of hospital-onset Clostridioides difficile infections.

BACKGROUND: A 1% potassium peroxymonosulphate-based environmental disinfectant (PPED) produces sodium hypochlorite when combined with sodium chloride, which functions as a disinfectant. However, little is known about the impact of hospital cleaning with PPED on hospital-onset Clostridioides difficile infection (HO-CDI). AIM: To reduce HO-CDI, we promoted antimicrobial stewardship and hospital ward cleaning with PPED: this study was conducted to evaluate their impact. METHODS: We began a promotion of post-prescription review with feedback for broad-spectrum antimicrobials and hospital ward cleaning with PPED. We reviewed the ratio of HO-CDI, PPED consumption, and days of therapy (DOT) of broad-spectrum antimicrobials between July 2014 and March 2018, dividing this time into the pre-promotion (July 2014 to June 2015) and post-promotion periods (July 2015 to March 2018). FINDINGS: Using interrupted time series analysis, an immediate significant change in HO-CDI was observed after intervention (P=0.03), although a downward trend was not observed over this period (P=0.19). Trends in PPED consumption significantly changed over this period (P=0.02). DOT of carbapenems decreased immediately after the intervention began (P<0.01). A Poisson regression analysis showed that PPED consumption and DOT of carbapenems were independent factors affecting HO-CDI (P=0.039 and 0.016, respectively). CONCLUSION: We revealed that DOT of carbapenems and use of PPED were associated with the HO-CDI ratio and that both interventions reduced the rate of HO-CDI. This is the first report on the impact of hospital ward cleaning with PPED on the reduction of HO-CDI.

Appropriateness of surgical antimicrobial prophylaxis in Japanese university hospitals.

BACKGROUND: Surgical antimicrobial prophylaxis (SAP) is one of the major purposes of antimicrobial use. AIM: To determine the adherence to the Japanese SAP guidelines in Japanese university hospitals. METHODS: This was a retrospective cohort study including 15 general hospitals and one dental university hospital. Up to three cases of 18 designated surgeries were evaluated regarding adherence to Japanese SAP guidelines: selection of antibiotics, timing of administration, re-dosing intervals, and duration of SAP. When all items were appropriate, surgery was defined as 'appropriate'. FINDINGS: In total, 688 cases (22-45 cases per surgery) were included. The overall appropriateness was 46.8% (322/688), and the appropriateness of each surgery ranged from 8.0% (2/25, cardiac implantable electronic device implantation) to 92.1% (35/38, distal gastrectomy). The appropriateness of each item was as follows: pre/intraoperative selections, 78.5% (540/688); timing of administrations, 96.0% (630/656); re-dosing intervals, 91.6% (601/656); postoperative selection, 78.9% (543/688); and duration of SAP, 61.4% (423/688). The overall appropriateness of hospitals ranged from 17.6% (9/51) to 73.3% (33/45). The common reasons for inappropriateness were the longer duration (38.5%, 265/688) and choice of antibiotics with a non-optimal antimicrobial spectrum before/during, and after surgery (19.0%, 131/688 and 16.9%, 116/688, respectively), compared to the guideline. CONCLUSIONS: Adherence to the guidelines differed greatly between the surgeries and hospitals. Large-scale multi-centre surveillance of SAP in Japanese hospitals is necessary to identify inappropriate surgeries, factors related to the appropriateness, and incidences of surgical site infections.

Association of variants in FABP4, FASN, SCD, SREBP1 and TCAP genes with intramuscular fat, carcass traits and body size in Chinese Qinchuan cattle.

This study aimed to genotype the variants in FABP4, FASN, SCD, SREBP1 and TCAP genes, and to analyze their associations with intramuscular fat (IMF) content, carcass traits and body size in Chinese Qinchuan cattle (QC). The association studies showed that the FABP4 c.220A > G polymorphism was significantly associated with ultrasound longissimus muscle depth (ULMD) and IMF, the FASN g.16024A > G polymorphism was significantly associated with ULMD and some body size traits, the SREBP1 84 bp indel was significantly associated with back fat thickness, ULMD and some body size traits. The frequencies of well-characterized A allele in FABP4 c.220A > G in Korean cattle (KOR) and Japanese Black cattle (JB), T allele in SCD g.8586C > T in KOR, SS genotype in SREBP1 84 bp indel in KOR and JB, DELDEL genotype in TCAP g.592-597CTGCAGinsdel in KOR were significantly higher than in Chinese cattle breeds. Thus, the associated four polymorphisms were expected to be genetic selection markers for meat quality, carcass traits and body size of QC.

Quantum device designing (QDD) for future semiconductor engineering.

In semiconductor device history, a trend is observed where narrowing and increasing the number of material layers improve device functionality, with diodes, transistors, thyristors, and superlattices following this trend. While superlattices promise unique functionality, they are not widely adopted due to a technology barrier, requiring advanced fabrication, such as molecular beam epitaxy and lattice-matched materials. Here, a method to design quantum devices using amorphous materials and physical vapor deposition is presented. It is shown that the multiplication gain M depends on the number of layers of the superlattice, N, as M = kN, with k as a factor indicating the efficiency of multiplication. This M is, however, a trade-off with transit time, which also depends on N. To demonstrate, photodetector devices are fabricated on Si, with the superlattice of Se and As2Se3, and characterized using current-voltage (I-V) and current-time (I-T) measurements. For superlattices with the total layer thicknesses of 200 nm and 2 µm, the results show that k200nm = 0.916 and k2µm = 0.384, respectively. The results confirm that the multiplication factor is related to the number of superlattice layers, showing the effectiveness of the design approach.

Pathophysiological analysis of uninephrectomized db/db mice as a model of severe diabetic kidney disease.

Diabetic nephropathy, included in diabetic kidney disease (DKD), is the primary disease leading to end-stage renal disease (ESRD) or dialysis treatment, accounting for more than 40% of all patients with ESRD or receiving dialysis. Developing new therapeutics to prevent the transition to ESRD or dialysis treatment requires an understanding of the pathophysiology of DKD and an appropriate animal model for drug efficacy studies. In this study, we investigated the pathophysiology of diabetic kidney disease with type 2 diabetes in uninephrectomized db/db mice. In addition, the nephrectomized db /db mice from 10 weeks to 42 weeks were used to assess the efficacy of long-term administration of the angiotensin-II-receptor antagonist losartan. The blood and urinary biochemical parameters, main pharmacological endpoint of the losartan therapy, were periodically measured. And at the end, histopathological analysis was performed. Uninephrectomized db/db mice clearly developed obesity and hyperglycemia from young age. Furthermore, they showed renal pathophysiological changes, such as increased urinary albumin-creatinine ratio (UACR) (the peak value 3104 ± 986 in 40-week-old mice), glomerular hypertrophy and increased fibrotic areas in the tubulointerstitial tubules. The blood pressure in the losartan group was significantly low compared to the normotensive Vehicle group. However, as expected, Losartan suppressed the increase in UACR (829±500) indicating the medication was sufficient, but the histopathological abnormalities including tubular interstitial fibrosis did not improve. These results suggest that the uninephrectomized db/db mice are useful as an animal model of the severe DKD indicated by the comparison of the efficacy of losartan in this model with the efficacy of losartan in clinical practice.

Immune disorders and sex differences in spontaneously diabetic Torii rats, type 2 diabetic model.

Type 2 diabetes (T2D) is believed to be a non-autoimmune metabolic disorder. However, there are increasing reports that some T2D patients have immune abnormalities. In addition, it is known that there are sex differences in the onset of diabetes and immune responses in humans. Spontaneously Diabetic Torii (SDT) rats, a non-obese T2D model, also have sex differences in the onset of diabetes, but the involvement of immune abnormalities in diabetes is unknown. In this study, we investigated immune abnormalities in SDT rats. Immune cell subset analysis was performed in male and female SDT rats and control Sprague-Dawley (SD) rats at 5, 11, and 17 weeks of age. Male and female SDT rats had swelling of the spleen and lymph nodes and a higher number of T cells and B cells in the blood, spleen, and lymph nodes than SD rats. Only male SDT rats developed diabetes at 17 weeks of age, and the number of classical and non-classical monocytes in the blood and spleen of male SDT rats was higher than that in male SD rats and female SDT rats that did not develop diabetes. Most of these findings were observed before the onset of diabetes (~11 weeks of age), suggesting that classical and non-classical monocytes may contribute to the development of diabetes in male SDT rats. In conclusion, SDT rats may be a useful T2D model involved in immune abnormalities, and further research will help elucidate the pathophysiology of T2D with immune abnormalities and develop new therapeutic agents.

Conceptual design of heavy ion beam probes on the PLATO tokamak.

Heavy ion beam probe (HIBP) systems have been designed for the new tokamak, PLATO [A. Fujisawa, AIP Conf. Proc. 1993, 020011 (2018)]. The designs have been completed, and the installations are in progress. Two HIBPs are being installed in toroidal sections 180° apart to investigate long-range correlations in the toroidal direction. Each HIBP consists of an injection beamline and a detection beamline as usual. Yet, one of the HIBPs is equipped with an additional detection beamline; the measurement positions of its two detection beamlines can be placed on almost the same magnetic surface yet at poloidal angles that differ by ∼180°. The use of three detection beamlines allows us to investigate spatial asymmetry and long-range correlations in both the toroidal and poloidal directions, simultaneously. The detected beam intensity is expected to be enough for turbulence measurements in almost the entire plasma region when the electron density is up to 1 × 1019 m-3 by selecting appropriate ion species for the probe beam. Each detector has three channels 10 mm apart, allowing measurement of local structures of micro-scale turbulence. Therefore, using the HIBPs on the PLATO tokamak will enable both local and global properties of plasma turbulence to be investigated, simultaneously.

Shallow slow earthquakes to decipher future catastrophic earthquakes in the Guerrero seismic gap.

The Guerrero seismic gap is presumed to be a major source of seismic and tsunami hazard along the Mexican subduction zone. Until recently, there were limited observations at the shallow portion of the plate interface offshore Guerrero, so we deployed instruments there to better characterize the extent of the seismogenic zone. Here we report the discovery of episodic shallow tremors and potential slow slip events in Guerrero offshore. Their distribution, together with that of repeating earthquakes, seismicity, residual gravity and bathymetry, suggest that a portion of the shallow plate interface in the gap undergoes stable slip. This mechanical condition may not only explain the long return period of large earthquakes inside the gap, but also reveals why the rupture from past M < 8 earthquakes on adjacent megathrust segments did not propagate into the gap to result in much larger events. However, dynamic rupture effects could drive one of these nearby earthquakes to break through the entire Guerrero seismic gap.

Evolución hacia la era digital de la cirugía ortognática: experiencia en un centro universitario / Evolution towards the digital era of orthognatic surgery: experience in a university center

Resumen Introducción: La incorporación de tecnologías en la práctica quirúrgica, ha cambiado la forma de enfrentar el proceso quirúrgico. Objetivo: Describir la experiencia de los últimos 9 años, en cirugía ortognática, con la incorporación de la cefalometría 3D. Materiales y Método: Se realizó una revisión retrospectiva de pacientes operados de cirugía ortognática durante el período enero de 2011 a agosto de 2018. Se registraron datos demográficos, quirúrgicos, tipo de planificación quirúrgica, complicaciones y resultados a largo plazo. Resultados: 21 pacientes requirieron cirugías ortognáticas. Se realizaron 16 cirugías bimaxilares (76%), 3 cirugías de avance maxilar superior (14%) y 2 cirugías de osteotomía sagital de rama (10%). Las principales etiologías fueron: 67% maloclusión clase III (n = 14), 28% maloclusión clase II (n = 6) y 5% desviación mandibular (n = 1). La planificación prequirúrgica virtual fue utilizada en 11 pacientes (52%). La tasa de complicaciones Clavien-Dindo > III fue 4,8% (n = 1). Conclusiones: En nuestra experiencia, las técnicas de cirugía ortognática son seguras. Las complicaciones de la serie fueron escasas y bien toleradas por los pacientes. Durante los últimos años y, de acuerdo a los avances tecnológicos, la incorporación de la planificación quirúrgica virtual 3D favoreció el desarrollo de la cirugía ortognática en nuestro centro.

Introduction: Technological advances have been incorporated into cranio-maxillo-facial surgery changing the clinical practice of surgeons. Aim: The aim of this article is to describe our experience in orthognatic surgery in the last 9-years, with the incorporation of 3D cephalometry. Materials and Method: A retrospective chart review was performed from January 2011 to August 2018 on patients undergoing Orthognatic Surgery. Demographic and surgical data, type of surgical planning, complications and long-term results were recorded. Results: A total of 21 patients underwent orthognatic surgery. Average age was 28 years (DE 8.1), 11 men (52.3%) and 10 women (47.61%). The principal surgeries performed were: 16 (76%) bimaxillary, 3 maxillary advancement surgery 3 (14%) and bilateral sagital split osteotomy 2 (10%). Ethiologies were: 14 patients (this 67%) with malocclusion class III, 6 patients (28%) with malocussion class II, and 1 patient (5%) with mandibular deviation. Virtual 3D presurgical planning was used in 11 patients (52%). The total of complications Clavien-Dindo > III was 4.8% (n = 1). None patient required reoperation. Satisfaction rate with the procedure was high. Conclusions: Based on our experience, orthognatic surgery techniques are safe. The complication rate was lower and well tolerated by patients. The introduction of virtual planning provided a better scenario to develop maxillo-facial surgery.

Moisturizing mechanism of glycerol and diglycerol on human stratum corneum studied by synchrotron X-ray diffraction.

OBJECTIVE: Polyols are moisturizers used in cosmetics. Using X-ray diffraction, we studied the moisturizingmechanism of polyol solutions in the stratum corneum (SC). We examined whether glycerol disrupts the ordered hydrocarbon chain packing structure in isolated SC, as previously proposed in an SC lipid model. METHODS: The SC samples were prepared by treatment with water and aqueous solutions of glycerol, diglycerol and glycerol/diglycerol. To examine the differences in the water-retention efficiency of polyols, using a solution cell, we performed dynamic X-ray diffraction to analyse the structural changes that occurred during water removal from the hydrated samples by a stream of dry nitrogen gas. We focused on two structures, the orthorhombic hydrocarbon chain packing structure in the intercellular lipids and the soft keratin in the corneocytes where most of the water is stored. RESULTS: The spacing formed by the soft keratin in the corneocytes immersed in a solution of water and diglycerol solution decreased rapidly by water removal. In contrast, it decreased gradually in the corneocytes immersed in a solution of glycerol and glycerol/diglycerol, indicating that the glycerol-containing solutions maintained the hydrated state of the corneocytes for longer. Furthermore, the characteristic change of the spacing in the orthorhombic hydrocarbon chain packing structure over time was observed during the drying process. The hydrated state was maintained longer, in water, followed by glycerol, diglycerol and glycerol/diglycerol, in increasing order. This is the first study to report such characteristic properties that could be indicators of the capacity of the SC to regulate water. CONCLUSION: The dynamic X-ray diffraction experiment on the structure of the soft keratin and the orthorhombic hydrocarbon chain packing structure during the drying of the hydrated SC provides an insight into the moisturizing mechanism of the polyol solutions in the SC. The results show that the glycerol/diglycerol solution functions as an effective SC moisturizer at the molecular level. Further, it was confirmed that the behaviour of glycerol in the isolated SC varies from that proposed in the SC lipid model, wherein glycerol was proposed to prevent the formation of a regular hydrocarbon chain packing structure.

OBJECTIF: les polyols sont des hydratants utilisés dans les cosmétiques. À l'aide de la diffractions des rayons X, nous avons étudié le mécanisme d'hydratation des solutions de polyols dans la couche cornée (stratum corneum, SC).Notre étude avait pour but de déterminer si le glycérol perturbe la structure d'empilement de la chaîne d'hydrocarbures ordonnée dans les SC isolés, comme proposé précédemment dans un modèle lipidique de SC. MÉTHODES: les échantillons de SC ont été préparés avec de l'eau et des solutions aqueuses de glycérol, de diglycérol et de glycérol/diglycérol. Pour examiner les différences d'efficacité de rétention d'eau des polyols à l'aide d'une cellule de solution, nous avons effectué une diffraction dynamique des rayons X pour analyser les changements structurels qui se sont produits pendant l'élimination de l'eau des échantillons hydratés par un flux d'azote sec. Nous avons mis l'accent sur deux structures, la structure d'empilement des chaînes d'hydrocarbures orthorhombiques dans les lipides intercellulaires et la kératine molle dans les cornéocytes où la majeure partie de l'eau est stockée. RÉSULTATS: l'espacement causé par la kératine molle dans les cornéocytes immergés dans une solution d'eau et de diglycérol a diminué rapidement en raison de l'élimination de l'eau. En revanche, il a diminué progressivement dans les cornéocytes immergés dans une solution de glycérol et de glycérol/diglycérol, ce qui indique que les solutions contenant du glycérol ont maintenu l'état hydraté des cornéocytes plus longtemps. De plus, la modification caractéristique de l'espacement dans la structure d'empilement de la chaîne d'hydrocarbures orthorhombique au fil du temps a été observée au cours du processus de séchage. L'état hydraté a été maintenu plus longtemps, dans l'eau, suivi par le glycérol, le diglycérol et le glycérol/diglycérol, dans un ordre croissant. C'est la première étude à faire état de telles propriétés caractéristiques qui pourraient être des indicateurs de la capacité du SC à réguler l'eau. CONCLUSION: l'expérience de diffraction dynamique des rayons X sur la structure de la kératine molle et la structure d'empilement de la chaîne d'hydrocarbures orthorhombique pendant le séchage du SC hydraté donne un aperçu du mécanisme hydratant des solutions de polyols dans le SC. Les résultats montrent que la solution de glycérol/diglycérol agit comme un hydratant de SC efficace au niveau moléculaire. De plus, il a été confirmé que le comportement du glycérol dans le SC isolé varie par rapport à celui proposé dans le modèle lipidique SC, où le glycérol a été proposé pour prévenir.

Influence of salt stress on C4 photosynthesis in Miscanthus sinensis Anderss.

Miscanthus sinensis Anderss. is a good candidate for C4 bioenergy crop development for marginal lands. As one of the characteristics of marginal lands, salinization is a major limitation to agricultural production. The present work aimed to investigate the possible factors involved in the tolerance of M. sinensis C4 photosynthesis to salinity stress. Seedlings of two accessions (salt-tolerant 'JM0119' and salt-sensitive 'JM0099') were subjected to 0 mm NaCl (control) or 250 mm NaCl (salt stress treatment) for 2 weeks. The chlorophyll content, parameters of photosynthesis and chlorophyll a fluorescence, activity of C4 enzymes and expression of C4 genes were measured. The results showed that photosynthesis rate, transpiration rate, chlorophyll content, PSII operating efficiency, coefficient of photochemical quenching, activity of phosphoenolpyruvate carboxylase (PEPC) and pyruvate, orthophosphate dikinase (PPDK) and gene expression of PEPC and PPDK under salinity were higher after long-term salinity exposure in 'JM0119' than in 'JM0099', while activity of NADP-malate dehydrogenase (NADP-MDH) and NADP-malic enzyme (NADP-ME), together with expression of NADP-MDH and NADP-ME, were much higher in 'JM0099' than in 'JM0119'. In conclusion, the increased photosynthetic capacity under long-term salt stress in the salt-tolerant relative to the salt-sensitive M. sinensis accession was mainly associated with non-stomatal factors, such as reduced chlorophyll loss, higher PSII operating efficiency, enhanced activity of PEPC and PPDK and relatively lower activity of NADP-ME.

Neighbourhood relationships moderate the positive association between family caregiver burden and psychological distress in Japanese adults: a cross-sectional study.

OBJECTIVES: Family caregiver burden is associated with higher psychological distress. However, little is known about the impact of neighbourhood relationships on caregivers' psychological distress. We examined whether neighbourhood relationships of caregivers moderate the association between family caregiver burden and psychological distress. STUDY DESIGN: This was a cross-sectional study. METHODS: We recruited 5321 Japanese adults who participated in the Japan Multi-Institutional Collaborative Cohort Study in the Okazaki area between 2013 and 2017. Participants completed self-reported questionnaires to measure psychological distress (Kessler 6: K6), subjective caregiver burden, and neighbourhood relationships. We performed a multivariable linear regression analysis in which caregiver burden was designated as an independent variable and the K6 score as a dependent variable, adjusting for demographics. The interaction term between caregiver burden and neighbourhood relationships was also included in the analysis. RESULTS: Data from a total of 5069 participants were included (mean age [standard deviation]: 63.1 years [10.3 years]; 2226 [43.9%] female). Caregiver burden was significantly and positively associated with psychological distress (compared with no burden, mild burden: ß = 0.24, P = 0.197; severe burden: ß = 0.60, P < 0.01; P for trend < 0.01). There was a significant negative interaction effect of caregiver burden × neighbourhood relationship on psychological distress (severe burden × good neighbourhood relationship: ß = -3.29, P < 0.01). CONCLUSIONS: A higher caregiver burden was associated with higher psychological distress, and neighbourhood relationships moderated this association. Our findings suggest that good neighbourhood relationships can buffer caregiving-associated psychological distress.

Effect of high ligation on survival of patients undergoing surgery for primary colorectal cancer and synchronous liver metastases.

BACKGROUND: Although R0 surgery is recommended for stage IV colorectal cancer, the degree of required lymphadenectomy has not been established. The aim of this study was to investigate the prognostic impact of high ligation (HL) of the feeding artery and the number of retrieved lymph nodes after R0 surgery for colorectal cancer and synchronous colorectal cancer liver metastasis (CRLM). METHODS: This was a multi-institutional retrospective analysis of patients with colorectal cancer and synchronous CRLM who had R0 surgery between January 1997 and December 2007. Clinical and pathological features were compared in patients who underwent HL and those who had a low ligation (LL). Kaplan-Meier analysis was performed to estimate the effect of HL on overall survival (OS). The impact of several risk factors on survival was analysed using the Cox proportional hazards model. RESULTS: Of 549 patients, 409 (74·5 per cent) had HL. Median follow-up was 51·4 months. HL significantly improved the 5-year OS rate (58·2 per cent versus 49·3 per cent for LL; P = 0·017). Multivariable analysis revealed HL to be a significant prognostic factor compared with LL (5-year mortality: hazard ratio (HR) 0·68, 95 per cent c.i. 0·51 to 0·90; P = 0·007). In subgroup analysis, the positive effect of HL on OS was greatest in patients with lymph node metastasis. CONCLUSION: HL of the feeding artery was associated with improved OS in patients with colorectal cancer and synchronous CRLM after R0 surgery.

ANTECEDENTES: Aunque se recomienda una cirugía R0 para el cáncer colorrectal (colorectal cancer, CRC) en estadio IV, no se ha establecido el grado de linfadenectomía requerida. El objetivo de este estudio fue investigar el impacto pronóstico de la ligadura alta (high ligation, HL) de la arteria que irriga el tumor y el número de ganglios linfáticos (lymph nodes, LN) identificados después de cirugía R0 en pacientes con cáncer colorrectal y metástasis hepáticas sincrónicas (colorectal cancer liver metastasis, CRLM). MÉTODOS: En este estudio se realizó un análisis retrospectivo multicéntrico de pacientes con CRC y CRLM sincrónicas en los que se realizó una cirugía R0 desde enero de 1997 hasta diciembre de 2007. Se compararon las características clínicas y patológicas entre los pacientes a los que, durante la cirugía R0, se practicó una HL frente a los que no se practicó esta técnica. El análisis de Kaplan-Meier se realizó para estimar el efecto de la HL en la supervivencia global (overall survival, OS). El impacto de varios factores de riesgo sobre la supervivencia se analizó utilizando el modelo de Cox de riesgo proporcional. RESULTADOS: Sobre un total de 549 pacientes, se realizó una HL en 409 (74,5%), y el período de seguimiento medio en esta cohorte fue de 51,4 meses. La HL mejoró significativamente la tasa de OS a los 5 años (HL 37,7% versus no HL 27,1%, P = 0,02). El análisis multivariable mostró que la HL era un factor pronóstico significativo en comparación con la no realización de una HL (cociente de riesgos instantáneos, hazard ratio, HR de muerte a 5 años = 0,68 (i.c. del 95% 0,51-0,90), P < 0,01)). En el análisis de subgrupos, el efecto positivo de la HL sobre la OS fue mayor en pacientes con metástasis ganglionares. CONCLUSIÓN: La ligadura alta de la arteria que irriga el tumor se asoció con una mejor OS en pacientes con CRC y CRLM sincrónicas después de una cirugía R0.