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1.
Phys Chem Chem Phys ; 25(37): 25408-25419, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37706318

RESUMEN

Directional fragment ejection from a tetrahedral molecule CH4 in linearly polarized two-color (ω and 2ω) asymmetric intense laser fields (50 fs, 1.4 × 1014 W cm-2, 800 nm and 400 nm) has been studied by three-dimensional ion coincidence momentum imaging. The H+ fragment produced from dissociative ionization, CH4 → H+ + CH3 + e-, is preferentially ejected on the larger amplitude side of the laser electric fields. Comparison with theoretical predictions by weak-field asymptotic theory shows that the observed asymmetry can be understood by the orientation selective tunneling ionization from the triply degenerated highest occupied molecular orbital (1t2) of CH4. A similar directional ejection of H+ was also observed for the low kinetic energy components of the two-body Coulomb explosion, CH4 → H+ + CH3+ + 2e-. On the other hand, the fragment ejection in the opposite direction were observed for the high energy component, as well as H2+ produced from the Coulomb explosion CH4 → H2+ + CH2+ + 2e-. Possible origins of the characteristic fragmentation are discussed.

2.
J Hosp Infect ; 2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37516279

RESUMEN

OBJECTIVE: Despite its efficacy and minimal invasiveness, the clean-contaminated nature of endoscopic transnasal surgery (ETS) may be susceptible to central nervous system surgical site infections (CNS-SSIs), especially when involving intradural exposure. However, the profiles of ETS-associated CNS-SSIs are not fully elucidated. METHODS: The institutional ETS cases performed between May 2017 and March 2023 were retrospectively analysed. The incidences of CNS-SSIs were calculated, and their risk factors examined. RESULTS: The incidence of CNS-SSIs was 2.3% (7/305) in the entire cohort and 5.0% (7/140) in ETSs with intradural exposure. All the CNS-SSIs were meningitis and developed following ETS with intradural exposure. The incidences were 0%, 5.6% and 5.8% in ETSs with Esposito grade 1, 2 and 3 intraoperative cerebrospinal fluid leakage, respectively. Among the pre- and intra-operative factors, body mass index (unit odds ratio (OR), 0.62; 95% confidence interval (CI), 0.44-0.89; P<0.01), serum albumin (unit OR, 0.03; 95% CI, 0.0007-0.92; P=0.02), and American Society of Anesthesiologists physical status score (unit OR, 20.7; 95% CI, 1.65-259; P<0.01) were significantly associated with CNS-SSIs. Moreover, postoperative cerebrospinal fluid leakage was also significantly associated with CNS-SSIs (OR, 18.4; 95% CI, 3.55-95.0; P<0.01). CONCLUSIONS: The incidence of ETS-associated CNS-SSIs is acceptably low. Intradural exposure was a prerequisite for CNS-SSIs. Malnutrition and poor comorbidity status should be recognized as important risks for CNS-SSIs in ETS.

4.
J Geophys Res Space Phys ; 128(3): e2022JA031092, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38440152

RESUMEN

We present in-depth analysis of three southward-moving meso-scale (ion-to magnetohydrodynamic-scale) flux transfer events (FTEs) and subsequent crossing of a reconnecting magnetopause current sheet (MPCS), which were observed on 8 December 2015 by the Magnetospheric Multiscale spacecraft in the subsolar region under southward and duskward magnetosheath magnetic field conditions. We aim to understand the generation mechanism of ion-scale magnetic flux ropes (ISFRs) and to reveal causal relationship among magnetic field structures, electromagnetic energy conversion, and kinetic processes in magnetic reconnection layers. Results from magnetic field reconstruction methods are consistent with a flux rope with a length of about one ion inertial length growing from an electron-scale current sheet (ECS) in the MPCS, supporting the idea that ISFRs can be generated through secondary reconnection in an ECS. Grad-Shafranov reconstruction applied to the three FTEs shows that the FTEs had axial orientations similar to that of the ISFR. This suggests that these FTEs also formed through the same secondary reconnection process, rather than multiple X-line reconnection at spatially separated locations. Four-spacecraft observations of electron pitch-angle distributions and energy conversion rate j·E'=j·E+ve×B suggest that the ISFR had three-dimensional magnetic topology and secondary reconnection was patchy or bursty. Previously reported positive and negative values of j·E', with magnitudes much larger than expected for typical MP reconnection, were seen in both magnetosheath and magnetospheric separatrix regions of the ISFR. Many of them coexisted with bi-directional electron beams and intense electric field fluctuations around the electron gyrofrequency, consistent with their origin in separatrix activities.

5.
J Geophys Res Space Phys ; 127(7): e2022JA030408, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36248013

RESUMEN

We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.

6.
Tech Coloproctol ; 26(7): 561-570, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35576085

RESUMEN

BACKGROUND: Recent studies have indicated the potential benefit of intraoperative near-infrared fluorescence imaging (NIR-FI) with indocyanine green in reducing early anastomotic leakage in colorectal surgery. Nonetheless, whether NIR-FI is effective in reducing structural sequelae of anastomotic leakage (SSAL) remains unclear. The aim of the present study was to investigate the impact of NIR-FI on SSAL after laparoscopic intersphincteric resection (ISR) of malignant rectal tumors. METHODS: This study was a retrospective single-center cohort study. A total of 293 consecutive patients who underwent elective laparoscopic ISR from May 2010 to August 2017 were included. Patients were divided into 2 groups; those who underwent elective laparoscopic ISR with lymphadenectomy for malignant rectal tumors using NIR-F (NIR-FI group) and those who underwent elective laparoscopic ISR with lymphadenectomy for malignant rectal tumors without using NIR-FI (control group). Thirty were excluded from the analyses (13 died, 7 had pelvic recurrence, and 10 were lost to follow-up). The primary endpoint was the rate of SSAL within 2 years after the primary resection, whereas the secondary endpoint was the rate of natural defecation via the anus at 2 years after the primary resection. Using various statistical analyses, such as propensity score matching, the rate of SSAL was compared between groups. RESULTS: A total of 263 patients were analyzed [177 males and 86 females, median age 61 (27-84) years]. Prior to propensity score matching (n = 263), NIR-FI was performed in 70 patients (26.6%) The rates of SSAL were 1.4% (1/70) in the NIR-FI group and 10.4% (20/193) in the control group (p = 0.02). After propensity score matching (n = 163), the rates of SSAL were 1.5% (1/66) in the NIR-FI group and 11.7% (12/103) in the control group (p = 0.02). Propensity score analyses, as well as simple regression analyses, revealed that NIR-FI was associated with a significantly lower risk of SSAL (OR 0.10-0.13; p = 0.03-0.05). CONCLUSIONS: NIR-FI is useful in reducing the rate of SSAL after laparoscopic ISR.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Canal Anal/diagnóstico por imagen , Canal Anal/patología , Canal Anal/cirugía , Anastomosis Quirúrgica , Fuga Anastomótica/diagnóstico por imagen , Fuga Anastomótica/etiología , Fuga Anastomótica/prevención & control , Estudios de Cohortes , Femenino , Humanos , Verde de Indocianina , Laparoscopía/efectos adversos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Imagen Óptica , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estudios Retrospectivos
7.
Phys Chem Chem Phys ; 24(15): 8962-8969, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35380001

RESUMEN

Dissociative tunneling ionization of tetrafluoromethane (CF4) in circularly polarized ultrashort intense laser fields (35 fs, 0.8 × 1014 W cm-2, 1035 nm), CF4 → CF4+ + e- → CF3+ + F + e-, has been studied by three-dimensional electron-ion coincidence momentum imaging. The photoelectron angular distribution in the recoil frame revealed that the dissociative tunneling ionization occurs efficiently when the laser electric field points from F to C. The obtained results are qualitatively consistent with the theoretical predictions by the weak-field asymptotic theory (WFAT) for tunneling ionization from the highest and next-highest occupied molecular orbitals, HOMO (1t1), and HOMO-1 (4t2), respectively. On the other hand, the angular distribution shows clear dependences on the polarization helicity, indicating that the breaking of the C-F bonds is sensitive to the helicity of the multicycle circularly polarized laser fields.

8.
Tech Coloproctol ; 26(2): 109-115, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34761314

RESUMEN

BACKGROUND: Placing a transanal endoscopic rectal purse-string suture (taEPS) is the crucial first component of transanal total mesorectal excision (taTME). However, no structured training is available to improve the procedure-specific skills for taEPS. The aim of this study was to create a performance rubric to improve taEPS skills and provide preliminary evidence for its validity. METHODS: A performance rubric was created based on technical considerations for taEPS, identified by consulting with taTME surgical and performance assessment experts. Ten independent, blinded raters assessed 10 videotaped taEPS procedures of consecutive taTME cases, at National Cancer Center Hospital East (NCCHE), Chiba, Japan, in January 2018-March 2019 using the rubric and the Global Operative Assessment of Laparoscopic Skills (GOALS). Internal consistency and inter-rater reliabilities were calculated. Videotaped taEPS procedures were timed and assessed by the rubric. Correlation between rubric scores and suturing times were analyzed. RESULTS: The rubric consists of four items: loading the needle (LN), atraumatic needle passage (AP), planned suture path (PS), and overall performance (OA). Videotaped performances were graded on a 3-point Likert scale; scores were calculated as sums of the points. Cronbach's α for internal consistency was 0.713. Inter-rater reliabilities were LN: 0.73, AP: 0.76, PS: 0.71, and OA: 0.70. Rubric and GOALS scores were strongly correlated (r = 0.964, p < 0.001). In 112 consecutive taEPS performances, rubric scores were strongly correlated with suturing time (r = - 0.69, p < 0.001). Surgeons' experience with taTME was associated with rubric scores and suturing time. CONCLUSIONS: This study provides preliminary validation for the taEPS skill performance rubric. The rubric's structured training may facilitate skill acquisition by providing trainees with critical clinical considerations.


Asunto(s)
Laparoscopía , Proctectomía , Neoplasias del Recto , Cirugía Endoscópica Transanal , Humanos , Laparoscopía/métodos , Complicaciones Posoperatorias/cirugía , Neoplasias del Recto/cirugía , Recto/cirugía , Suturas , Cirugía Endoscópica Transanal/métodos
9.
J Small Anim Pract ; 63(1): 45-51, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34585398

RESUMEN

OBJECTIVES: To characterise the clinical signs of suspected cerebrovascular disease in dogs. MATERIALS AND METHODS: Medical records of one hospital were searched from November 2009 to December 2016 for dogs that suffered of cerebrovascular disease. We diagnosed cerebrovascular disease based on acute onset, clinical signs and magnetic resonance imaging findings. The medical history, clinical signs, concurrent disease, area of infarction, cerebrospinal fluid results, month at onset and outcome were investigated in the cerebrovascular disease group and in a control group (dogs with brain disorders other than cerebrovascular disease). RESULTS: A total of 122 CVD cases were extracted from the 5312 patients that visited during the study period. Of these 122 cases, 66 (1.2%) matched the subject selection criteria of our study and were included in the analysis. Forebrain infarction was observed in 51 of 66 cases, of which 24 (47.1%) suffered from seizures. The number of dogs diagnosed with cerebrovascular disease was disproportionately high in August (nine of 59 cases) and December (13 of 59 cases). In the outcome survey, deterioration was observed in 11 of 55 cases. CLINICAL SIGNIFICANCE: Seizure is an important clinical sign of cerebrovascular disease in dogs. There was a significant seasonal variation in the number of dogs diagnosed with cerebrovascular disease in Japan. Clinical features observed in this report differ from those of previous reports and highlight the need for additional research in this area.


Asunto(s)
Trastornos Cerebrovasculares , Enfermedades de los Perros , Animales , Trastornos Cerebrovasculares/diagnóstico por imagen , Trastornos Cerebrovasculares/veterinaria , Enfermedades de los Perros/diagnóstico por imagen , Enfermedades de los Perros/patología , Perros , Imagen por Resonancia Magnética/veterinaria , Estudios Retrospectivos , Convulsiones/veterinaria
10.
AJNR Am J Neuroradiol ; 42(12): 2138-2145, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34620595

RESUMEN

BACKGROUND AND PURPOSE: The hemodynamics associated with cerebral AVMs have a significant impact on their clinical presentation. This study aimed to evaluate the hemodynamic features of AVMs using 3D phase-contrast MR imaging with dual velocity-encodings. MATERIALS AND METHODS: Thirty-two patients with supratentorial AVMs who had not received any previous treatment and had undergone 3D phase-contrast MR imaging were included in this study. The nidus diameter and volume were measured for classification of AVMs (small, medium, or large). Flow parameters measured included apparent AVM inflow, AVM inflow index, apparent AVM outflow, AVM outflow index, and the apparent AVM inflow-to-outflow ratio. Correlation coefficients between the nidus volume and each flow were calculated. The flow parameters between small and other AVMs as well as between nonhemorrhagic and hemorrhagic AVMs were compared. RESULTS: Patients were divided into hemorrhagic (n = 8) and nonhemorrhagic (n = 24) groups. The correlation coefficient between the nidus volume and the apparent AVM inflow and outflow was .83. The apparent AVM inflow and outflow in small AVMs were significantly smaller than in medium AVMs (P < .001 for both groups). The apparent AVM inflow-to-outflow ratio was significantly larger in the hemorrhagic AVMs than in the nonhemorrhagic AVMs (P = .02). CONCLUSIONS: The apparent AVM inflow-to-outflow ratio was the only significant parameter that differed between nonhemorrhagic and hemorrhagic AVMs, suggesting that a poor drainage system may increase AVM pressure, potentially causing cerebral hemorrhage.


Asunto(s)
Malformaciones Arteriovenosas Intracraneales , Hemorragia Cerebral , Hemodinámica , Humanos , Imagenología Tridimensional , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Imagen por Resonancia Magnética
11.
BJS Open ; 5(5)2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34553225

RESUMEN

BACKGROUND: Robot-assisted laparoscopic surgery has several advantages over conventional laparoscopy. However, population-based comparative studies for low anterior resection are limited. This article aimed to compare peri-operative results of robot-assisted low anterior resection (RALAR) and laparoscopy. METHODS: This retrospective cohort study used data from patients treated with RALAR or conventional laparoscopic low anterior resection (CLLAR) between October 2018 and December 2019, as recorded in the Japanese National Clinical Database, a data set registering clinical information, perioperative outcomes, and mortality. Of note, the registry does not include information on the tumour location (centimetres from the anal verge) and diverting stoma creation. Perioperative outcomes, including rate of conversion to open surgery, were compared between RALAR and CLLAR groups. Confounding factors were adjusted for using propensity score matching. RESULTS: Of 21 415 patients treated during the study interval, 20 220 were reviewed. Two homogeneous groups of 2843 patients were created by propensity score matching. The conversion rate to open surgery was significantly lower in the RALAR group than in the CLLAR group (0.7 versus 2.0 per cent; P < 0.001). The RALAR group had a longer operating time (median: 352 versus 283 min; P < 0.001), less intraoperative blood loss (15 versus 20 ml; P < 0.001), a lower in-hospital mortality rate (0.1 versus 0.5 per cent; P = 0.007), and a shorter postoperative hospital stay (median: 13 versus 14 days; P < 0.001) compared with the CLLAR group. The CLLAR group had a lower rate of readmission within 30 days (2.4 versus 3.3 per cent; P = 0.045). CONCLUSION: These data highlight the reduced conversion rate, in-hospital mortality rate, intraoperative blood loss, and length of postoperative hospital stay for rectal cancer surgery in patients treated using robot-assisted laparoscopic surgery compared with laparoscopic low anterior resection.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Robótica , Humanos , Japón/epidemiología , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
12.
BJS Open ; 5(2)2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33839748

RESUMEN

BACKGROUND: This study aimed to analyse the perioperative results from a national dataset of rectal cancer resections in elderly patients. METHODS: The clinical records of patients undergoing rectal cancer surgery between 2012 and 2014 were retrieved from the Japanese National Clinical Database and analysed retrospectively. Patients were categorized according to age and those 80 years or older were defined as elderly. Subgroups were also defined according to the surgical approach (laparoscopy versus open surgery). The short-term outcomes, including mortality, anastomotic leak, surgical site infections and medical complications were compared between subgroups. RESULTS: Of 56 175 patients undergoing rectal cancer surgery, some 6717 patients were elderly and laparoscopy was performed in 46.8 per cent of the sample. When comparing laparoscopy and open surgery in elderly patients, the operative mortality rate (1.5 versus 2.8 per cent; P < 0.001), the incidence of anastomotic leakage (5.2 versus 6.5 per cent; P = 0.026), surgical site infections (6.0 versus 8.0 per cent; P = 0.001), pneumonia (1.4 versus 2.5 per cent; P = 0.001), renal failure (0.7 versus 1.3 per cent; P = 0.016) and cardiac events (0.3 versus 0.8 per cent; P = 0.008) were lower for laparoscopy than for open surgery. The overall complication rate in elderly patients (19.5 per cent) was comparable to that in the younger group (P = 0.07). However, incidence of systemic complications was significantly higher in elderly than in younger patients (all P < 0.001). CONCLUSION: Laparoscopy was safe and feasible in elderly patients compared with open surgery. However, the rates of systemic complications were significantly higher than in younger patients.


Asunto(s)
Laparoscopía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Neoplasias del Recto/cirugía , Anciano , Anciano de 80 o más Años , Fuga Anastomótica/epidemiología , Bases de Datos Factuales , Estudios de Factibilidad , Femenino , Humanos , Japón/epidemiología , Laparoscopía/mortalidad , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neumonía/epidemiología , Neoplasias del Recto/mortalidad , Estudios Retrospectivos , Infección de la Herida Quirúrgica/epidemiología , Resultado del Tratamiento
13.
J Geophys Res Space Phys ; 126(11): e2021JA029841, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35864949

RESUMEN

A method based on electron magnetohydrodynamics (EMHD) for the reconstruction of steady, two-dimensional plasma and magnetic field structures from data taken by a single spacecraft, first developed by Sonnerup et al. (2016), https://doi.org/10.1002/2016ja022430, is extended to accommodate inhomogeneity of the electron density and temperature, electron inertia effects, and guide magnetic field in and around the electron diffusion region (EDR), the central part of the magnetic reconnection region. The new method assumes that the electron density and temperature are constant along, but may vary across, the magnetic field lines. We present two models for the reconstruction of electron streamlines, one of which is not constrained by any specific formula for the electron pressure tensor term in the generalized Ohm's law that is responsible for electron unmagnetization in the EDR, and the other is a modification of the original model to include the inertia and compressibility effects. Benchmark tests using data from fully kinetic simulations show that our new method is applicable to both antiparallel and guide-field (component) reconnection, and the electron velocity field can be better reconstructed by including the inertia effects. The new EMHD reconstruction technique has been applied to an EDR of magnetotail reconnection encountered by the Magnetospheric Multiscale spacecraft on 11 July 2017, reported by Torbert et al. (2018), https://doi.org/10.1126/science.aat2998 and reconstructed with the original inertia-less version by Hasegawa et al. (2019), https://doi.org/10.1029/2018ja026051, which demonstrates that the new method better performs in recovering the electric field and electron streamlines than the original version.

14.
Dis Esophagus ; 34(3)2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-32895704

RESUMEN

The number of elderly patients with esophageal cancer has increased in recent years. The use of thoracoscopic esophagectomy has also increased, and its minimal invasiveness is believed to contribute to postoperative outcomes. However, the short- and long-term outcomes in elderly patients remain unclear. This study aimed to elucidate the safety and feasibility of minimally invasive esophagectomy in elderly patients. This retrospective study included 207 patients who underwent radical thoracoscopic esophagectomy for thoracic esophageal squamous cell carcinoma at Kobe University Hospital between 2005 and 2014. Patients were divided into non-elderly (<75 years) and elderly (≥75 years) groups. A propensity score matching analysis was performed for sex and clinical T and N stage, with a total of 29 matched pairs. General preoperative data, surgical procedures, intraoperative data, postoperative complications, in-hospital death, cancer-specific survival, and overall survival were compared between groups. The elderly group was characterized by lower preoperative serum albumin levels and higher American Society of Anesthesiologists grade. Intraoperative data and postoperative complications did not differ between the groups. The in-hospital death rate was 4% in the elderly group, which did not significantly differ from the non-elderly group. Cancer-specific survival was similar between the two groups. Although overall survival tended to be poor in the elderly group, it was not significantly worse than that of the non-elderly group. In conclusion, the short- and long-term outcomes of minimally invasive esophagectomy in elderly versus non-elderly patients were acceptable. Minimally invasive esophagectomy is a safe and feasible modality for elderly patients with appropriate indications.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Anciano , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago/cirugía , Esofagectomía/efectos adversos , Estudios de Factibilidad , Mortalidad Hospitalaria , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento
15.
Geophys Res Lett ; 47(13): e2020GL087574, 2020 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-32999512

RESUMEN

At the Earth's low-latitude magnetopause, clear signatures of the Kelvin-Helmholtz (KH) waves have been frequently observed during periods of the northward interplanetary magnetic field (IMF), whereas these signatures have been much less frequently observed during the southward IMF. Here, we performed the first 3-D fully kinetic simulation of the magnetopause KH instability under the southward IMF condition. The simulation demonstrates that fast magnetic reconnection is induced at multiple locations along the vortex edge in an early nonlinear growth phase of the instability. The reconnection outflow jets significantly disrupt the flow of the nonlinear KH vortex, while the disrupted turbulent flow strongly bends and twists the reconnected field lines. The resulting coupling of the complex field and flow patterns within the magnetopause boundary layer leads to a quick decay of the vortex structure, which may explain the difference in the observation probability of KH waves between northward and southward IMF conditions.

16.
J Geophys Res Space Phys ; 125(4): e2019JA027665, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32714734

RESUMEN

On 5 May 2017, MMS observed a crater-type flux rope on the dawnside tailward magnetopause with fluctuations. The boundary-normal analysis shows that the fluctuations can be attributed to nonlinear Kelvin-Helmholtz (KH) waves. Reconnection signatures such as flow reversals and Joule dissipation were identified at the leading and trailing edges of the flux rope. In particular, strong northward electron jets observed at the trailing edge indicated midlatitude reconnection associated with the 3-D structure of the KH vortex. The scale size of the flux rope, together with reconnection signatures, strongly supports the interpretation that the flux rope was generated locally by KH vortex-induced reconnection. The center of the flux rope also displayed signatures of guide-field reconnection (out-of-plane electron jets, parallel electron heating, and Joule dissipation). These signatures indicate that an interface between two interlinked flux tubes was undergoing interaction, causing a local magnetic depression, resulting in an M-shaped crater flux rope, as supported by reconstruction.

17.
Scand J Rheumatol ; 49(4): 301-311, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32286129

RESUMEN

OBJECTIVE: The complement cascade, especially the alternative pathway of complement, has been shown in basic research to be associated with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). We aimed to elucidate relationships between serum complement components and clinical characteristics in AAV. METHOD: In a nationwide prospective cohort study (RemIT-JAV-RPGN), we measured the serum levels of C1q, C2, C3, C3b/iC3b, C4, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, mannose-binding lectin, and properdin in 52 patients with microscopic polyangiitis (MPA) and 39 patients with granulomatosis with polyangiitis (GPA). RESULTS: The properdin level of MPA and GPA was significantly lower than that of healthy donors. The properdin level was negatively correlated with the Birmingham Vasculitis Activity Score (BVAS) (ρ = -0.2148, p = 0.0409). The factor D level at 6 months was significantly positively correlated with the Vasculitis Damage Index (VDI) at 6, 12, and 24 months (ρ = 0.4207, 0.4132, and 0.3115, respectively). Patients with a higher ratio of C5a to C5 had higher neutrophil percentage and serum immunoglobulin G levels, and significantly lower creatinine levels. Cluster analysis divided the MPA and GPA patients into three subgroups. A principal component (PC) analysis aggregated 15 types of complements into alternative pathway-related PC 1 and complement classical pathway and common pathway-related PC 2. CONCLUSIONS: The serum levels of properdin and factor D were correlated with the BVAS and the VDI in MPA and GPA, respectively. Our analyses suggested the pathological heterogeneity of MPA and GPA from the aspect of complement components.


Asunto(s)
Proteínas del Sistema Complemento/metabolismo , Granulomatosis con Poliangitis/sangre , Poliangitis Microscópica/sangre , Anciano , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Análisis por Conglomerados , Femenino , Granulomatosis con Poliangitis/tratamiento farmacológico , Granulomatosis con Poliangitis/etiología , Humanos , Inmunosupresores/uso terapéutico , Masculino , Poliangitis Microscópica/tratamiento farmacológico , Poliangitis Microscópica/etiología , Persona de Mediana Edad , Análisis de Componente Principal , Estudios Prospectivos , Recurrencia , Inducción de Remisión
18.
BJS Open ; 4(3): 508-515, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32243733

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Ligadura/métodos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Anciano , Neoplasias Colorrectales/mortalidad , Femenino , Hepatectomía , Humanos , Japón/epidemiología , Neoplasias Hepáticas/mortalidad , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia
19.
Int J Oral Maxillofac Surg ; 49(8): 984-992, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32070653

RESUMEN

The objectives of this study were to evaluate survival in 141 patients with stage II-IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Boca/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino/uso terapéutico , Docetaxel , Fluorouracilo , Humanos , Recurrencia Local de Neoplasia , Peplomicina/uso terapéutico , Taxoides/uso terapéutico
20.
Rev Sci Instrum ; 91(1): 014704, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32012645

RESUMEN

In this paper, we present noncontact and noninvasive vital signal detection using a microwave reflectometer. Elimination of noise components due to random movement of human subjects has been the biggest issue for microwave measurement. Appropriate filtering, amplitude control of the reflectometer signal, and cross correlation among multiple reflectometers together with new algorithms have enabled motion artifact elimination, signal peak detection, and data processing for various parameters related to heart rate (HR) and heart rate variability (HRV). We focus here on the real time measurements of instantaneous HR and HRV for practical use. The evaluation by microwave reflectometry is completely noninvasive and feasible even through clothing, which is extremely effective for health maintenance in daily life as well as for preventing sudden death related to, for example, coronary heart disease and ventricular arrhythmia.


Asunto(s)
Frecuencia Cardíaca , Microondas , Procesamiento de Señales Asistido por Computador , Femenino , Humanos , Masculino
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