Profiles of central nervous system surgical site infections in endoscopic transnasal surgery exposing the intradural space

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.

A Novel Method of Calculating the Drained Liver Volume Using a 3D Volume Analyzer for Biliary Drainage of Unresectable Malignant Hilar Biliary Obstruction

OBJECTIVES

In patients with unresectable malignant hilar biliary obstruction (UMHBO), drainage of ≥ 50% liver volume correlates with better clinical outcomes. Accurately measuring the liver volume to be drained by biliary stents is required. We aimed to develop a novel method for calculating the drained liver volume (DLV) using a 3D volume analyzer (3D volumetry), and assess the usefulness for drainage in patients with UMHBO.

METHODS

Three-dimensional volumetry comprises the following steps: (1) manual tracing of bile duct using 3D imaging system; (2) 3D reconstruction of bile duct and liver parenchyma; and (3) calculating DLV according to the 3D distribution of bile ducts. Using 3D volumetry, we reviewed data of patients who underwent biliary drainage for UMHBO, calculated the DLV, and determined the association between DLV and biliary drainage outcome.

RESULTS

There were 104 eligible cases. The mean DLV was 708 ± 393 ml (53% ± 21%). and 65 patients (63%) underwent drainage of   ≥50% liver volume. The clinical success rate was significantly higher in patients with DLV ≥ 50% than in patients with DLV < 50% (89% vs. 28%, P < 0.001). The median time to recurrence of biliary obstruction (TRBO) and survival time were significantly longer in patients with DLV ≥ 50% than in patients with DLV < 50% (TRBO, 292 vs. 119 days, P = 0.03; survival, 285 vs. 65days, P = 0.004, log-rank test, respectively).

CONCLUSIONS

Three-dimensional volumetry, a novel method to calculate DLV accurately according to bile duct distribution was useful for drainage in UMHBO patients.

[Double extrahepatic bile duct with pancreaticobiliary maljunction:a case report]

A 76-year-old woman with a suspected double extrahepatic bile duct was referred to our hospital. MRCP revealed that the left hepatic and posterior ducts combined to form the ventral bile duct and that the anterior duct formed the dorsal bile duct. ERCP demonstrated that the ventral bile duct was linked with the Wirsung duct. Amylase levels in the bile were unusually high. Based on these findings, we diagnosed a double extrahepatic bile duct with pancreaticobiliary maljunction and choledocholithiasis. Duplicate bile duct resection and bile duct jejunal anastomosis were performed considering the risk of biliary cancer due to pancreaticobiliary maljunction. The resected bile duct epithelium demonstrated no atypia or hyperplastic changes.

Biomaterial-Based Biomimetic Visual Sensors: Inkjet Patterning of Bacteriorhodopsin

Biomimetic visual sensors utilizing bacteriorhodopsin (bR) were fabricated by using an inkjet method. The inkjet printer facilitated the jetting of the bR suspension, allowing for the deposition of bR films. The resulting inkjet-printed bR film exhibited time-differential photocurrent response characteristics similar to those of a dip-coated bR film. By adjusting the number of printed bR film layers, the intensity of the photocurrent could be easily controlled. Moreover, the inkjet printing technique enabled unconstrained patterning, facilitating the design of various visual information processing functions, such as visual filters. In this study, we successfully fabricated two visual filters, namely, a two-dimensional Difference of Gaussian (DOG) filter and a Gabor filter. The printed DOG filter demonstrated edge detection capabilities corresponding to contour recognition in visual receptive fields. On the other hand, the printed Gabor filter proved effective in detecting objects of specific sizes as well as their motion and orientation. The integration of bR and the inkjet method holds significant potential for the widespread implementation of highly functional biomaterial-based visual sensors. These sensors have the capability to provide real-time visual information while operating in an energy-efficient manner.

Dissociative ionization and Coulomb explosion of CH4 in two-color asymmetric intense laser fields

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.

Ion-Scale Magnetic Flux Rope Generated From Electron-Scale Magnetopause Current Sheet: Magnetospheric Multiscale Observations

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 + v e × 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.

Electrophysiological characteristics and catheter ablation of atypical fast-slow atrioventricular nodal reentrant tachycardia using an inferolateral left atrial slow pathway

Background

Understandings of subtypes of atypical atrioventricular nodal reentrant tachycardia (AVNRT) using variants of slow pathway (SP) are still growing. Inferolateral (inf-lat-) left atrial (LA) SP is a rare variant extending into an inf-lat-LA along the mitral annulus (MA).

Purpose

To characterize an unknown subtype of atypical fast-slow (F/S-) AVNRT using an inf-lat-LA-SP as a retrograde limb (inf-lat-LA-F/S-AVNRT).

Methods

This Japanese multicenter retrospective study enrolled 4 patients of inf-lat-LA-F/S-AVNRT that was characterized by the earliest site of atrial activation during tachycardia (EAA) between 3 and 6 o'clock along the MA. The diagnosis was made by an exclusion of AV reentrant tachycardia (AVRT) and atrial tachycardia (AT) according to the standard criteria and was confirmed by successful elimination of tachycardia and the inf-lat-LA-SP.

Results

Surface ECG during tachycardia revealed long RP appearance except one who had short RP due to a short conduction time across the inf-lat-LA-SP. During tachycardia, far-field LA activation preceding near-field activation of coronary sinus (CS) musculature was visible in the CS recording in 2. Retrograde conduction via the inf-lat-LA-SP with a decremental delay was consistently reproducible with ventricular stimulation in 2, 1 of whom had double atrial response, while it was always masked by the presence of a retrograde conduction via the fast pathway in 1 and a retrograde block at the lower common pathway in 1. An injection of a small dose of ATP transiently interrupted a retrograde conduction over the inf-lat-LA-SP, suggesting its ATP-sensitivity. Exclusion of AVRT was made by no resetting of tachycardia with left ventricular extrastimulus in 2 and VA dissociation during overdrive pacing of tachycardia in remaining 2. Exclusion of AT was made by V-A-V response after ventricular entrainment in 1 and termination without atrial capture by ventricular pacing in 2. Ablation of the right-sided SP was unsuccessful to eliminate the tachycardia, but ablation at or near the EAA by transseptal approach was successful to cure the tachycardia, associated with an elimination of a retrograde conduction over the inf-lat-LA-SP following a development of an accelerated junction rhythm in all. Low-frequency potentials preceding local atrial activation, consistent with a retrograde activation via the inf-lat-LA-SP were detected along the MA medial to the EAA in 1.

Conclusions

Differential diagnosis of tachycardia with the EAA in the inf-lat-LA and especially long RP appearance should include inf-lat-LA-F/S-AVNRT. Presumed arrhythmogenic substrate of the inf-lat-LA-SP seemed to be consistent with the remnant of embryogenic AV ring tissue in the electropharmacological and locational characteristics. Successful elimination of this AVNRT can be obtained by ablation of the inf-lat-LA-SP, but not of the right-sided SP.

Funding Acknowledgement

Type of funding sources: None.

Novel Transparent Films Composed of Bisphenol-A Polycarbonate and Copolyester

In this paper, the structure and properties of transparent films composed of bisphenol-A polycarbonate (PC) and a commercially available copolyester, poly(1,4-cyclohexanedimethanol-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol-co-terephthalate) (CPE), were studied. Both PC and CPE films are known to be transparent with good mechanical toughness. It was found that PC/CPE (50/50) showed miscibility in both the molten and solid states, indicating that there is a high possibility for the blend system to be miscible in the whole blend ratios. Because of the miscibility, the blend films showed no light scattering originating from phase separation. The mechanical properties of the films, such as Young’s modulus, yield stress, and strain at break, were determined by the blend ratio, and the glass transition temperature increased with the PC content, which corresponded well with the values predicted by the Fox equation. These results demonstrate that the thermal and mechanical properties of the films can only be controlled by the blend ratio. Since these transparent films showed excellent mechanical toughness irrespective of the blend ratios, they can be employed in various applications.

Magnetic Field Annihilation in a Magnetotail Electron Diffusion Region With Electron-Scale Magnetic Island

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.

Helicity-dependent dissociative tunneling ionization of CF4 in multicycle circularly polarized intense laser fields

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.

Reconstruction of the Electron Diffusion Region With Inertia and Compressibility Effects

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.

Fast-slow atrioventricular nodal reentrant tachycardia phenotype mimicking the slow-slow type

Background

Fast-slow (F/S-) atrioventricular (AV) nodal reentrant tachycardia (AVNRT) is characterized by a short atrio-His (AH) interval and the earliest site of atrial activation (EAA) in the proximal coronary sinus (EAA-CS), while slow-slow (S/S-) AVNRT presents a long AH interval and EAA-CS. Those intracardiac appearances are initial indicators for making a diagnosis.

Purpose

To identify an unknown phenotype of F/S-AVNRT.

Methods

Among 46 consecutive patients with F/S-AVNRT, 6 patients (1 man, age 59±9) had an apparent but not typical (pseudo-) S/S-AVNRT during an electrophysiologic study. In 2 patients, pseudo-S/S-AVNRT was clinically documented.

Results

In all 6 patients, the diagnosis of F/S-AVNRT was made by an exclusion of atrial tachycardia with findings of 1) a V-A-V response following ventricular entrainment or 2) termination without atrial capture by ventricular pacing, and an exclusion of AV reentrant tachycardia with a ventriculoatrial dissociation during an initial (so-called QRS transition) zone of ventricular entrainment. An initial A-A-V activation sequence on atrial induction of F/S-AVNRT observed in 1 patient and Wenckebach-type AV block during ongoing F/S-AVNRT developing in 3 patients suggested the presence of the lower common pathway (LCP). Like the typical S/S-AVNRT, pseudo-S/S-AVNRT was induced with atrial stimulation after a jump in the AH interval or double ventricular response. However, in all patients, the pseudo-S/S-AVNRT transited to F/S-AVNRT following AV block in a single cycle and/or pseudo-S/S-AVNRT transited from spontaneously or triggered by atrial contractions. Importantly, on these transitions, the atrial cycle length (CL) and EAA-CS remained unchanged, that is, the atrial CL of S/S-AVNRT was almost identical to that of F/S-AVNRT, suggesting that the essential circuit of both tachycardias was identical. Actually, both tachycardias were cured by ablation at a single site in the traditional slow pathway (SP). Collectively, the pseudo-S/S-AVNRT was diagnosed as another phenotype of F/S-AVNRT accompanied by sustained antegrade conduction via another bystander (likely the left-sided or superior) SP breaking through the His bundle owing to the repetitive antegrade block at the LCP occurring by linking phenomenon, thus representing a long AH interval during the ongoing F/S-AVNRT. When the antegrade conduction is blocked at the bystander SP during the pseudo-S/S-AVNRT, releasing the linking phenomenon, the subsequent antegrade conduction reach the His-bundle via the fast pathway, thus returning to F/S-AVNRT.

Conclusions

An unknown, but not rare F/S-AVNRT phenotype exists that apparently mimics the typical S/S-AVNRT and is also an unknown subtype of apparent S/S-AVNRT. The presence of this pseudo-S/S-AVNRT suggests the limitation of classifying types of AVNRT based on AH and HA intervals during tachycardia. Understandings of this phenotype can advance a diagnosis of atypical AVNRT with multiple phenotypes.

Funding Acknowledgement

Type of funding sources: None.

Hemodynamic Analysis of Cerebral AVMs with 3D Phase-Contrast MR Imaging

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.

Characteristics and outcome of suspected cerebrovascular disease in dogs: 66 cases (2009-2016)

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.

Outcomes of robot-assisted versus conventional laparoscopic low anterior resection in patients with rectal cancer: propensity-matched analysis of the National Clinical Database in Japan

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.

Safety and feasibility of laparoscopic surgery for elderly rectal cancer patients in Japan: a nationwide study

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.

Safety and feasibility of minimally invasive esophagectomy for elderly esophageal cancer patients

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.

Increased oxygen uptake and utilization in the peripheral muscles, rather than cardiac function reserve, may be determinants of increased peak VO2 by cardiac rehabilitation in heart failure

Background

Peak oxygen consumption (peak VO2) is a major prognostic parameter in heart failure (HF). Previous studies have shown a relationship between peak VO2 and impaired oxygen uptake and utilization in the peripheral muscles. The purpose of this study was to clarify the determinant of increased peak VO2 by cardiac rehabilitation (CR) in patients with HF.

Methods

We performed echocardiography during upright ramp bicycle cardiopulmonary exercise test in 30 HF patients (61±1 years of age, 80% male) before and 6 months after CR. HR reserve was determined as the change in HR from rest to peak exercise, expressed as a percentage of the predicted maximal HR reserve. Elastance index (EAI) and LV end-systolic elastance index (ELVI) were derived as the ratio of end-systolic pressure to stroke volume index and end-systolic volume index, respectively. End-systolic pressure was estimated from the equation 0.9 × brachial systolic blood pressure. Ventriculo-arterial coupling (VAC) was calculated as the quotient of EAI and ELVI. The ratio of LDEDVI to E/e' mean was used to evaluate LV diastolic compliance. Systemic vascular resistance index was calculated as mean arterial pressure divided by echocardiography calculated cardiac index and multiplied by 80. The arterial venous oxygen content difference (C (A-V) O2 gradient) was calculated by using the Fick equation as: VO2/echocardiography calculated cardiac output.

Results

Peak VO2 and C (A-V) O2 gradient were increased by CR. However, heart rate reserve, systolic reserve, VAC, diastolic reserve and vasodilation reserve were unchanged by CR (Table 1).

Conclusions

Increased oxygen uptake and utilization in the peripheral muscles, rather than cardiac function reserve, may be determinants of increased peak VO2 by CR in HF.

Table 1

Funding Acknowledgement

Type of funding source: None

Decay of Kelvin-Helmholtz Vortices at the Earth's Magnetopause Under Pure Southward IMF Conditions

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.

Complement profile in microscopic polyangiitis and granulomatosis with polyangiitis: analysis using sera from a nationwide prospective cohort study

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.

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.

Magnetic Reconnection Inside a Flux Rope Induced by Kelvin-Helmholtz Vortices

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.

Preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil for oral squamous cell carcinoma

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.

Non-contact and real-time measurement of heart rate and heart rate variability using microwave reflectometry

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.

TRITIUM, HYDROGEN AND OXYGEN ISOTOPE COMPOSITIONS IN MONTHLY PRECIPITATION SAMPLES COLLECTED AT TOKI, JAPAN

Monthly precipitation samples have been collected at Toki, Japan, from November 2013 to March 2017. In this report, selected data were analysed to identify the regional hydrogen and oxygen isotope compositions. Tritium (3H) concentration in the precipitation ranged from 0.10 to 0.61 Bq L-1 and higher 3H concentrations were observed in spring rather than in other seasons. This range was similar to values reported in Chiba City, Japan. 3H concentration and the ratio d-excess, and δD values were roughly clustered according to each separate season. These regional hydrogen and oxygen isotope compositions will be used for environmental assessments of effects of the deuterium plasma experiments of the large fusion test device.

Comparisons of hamstring flexibility between individuals with and without low back pain: systematic review with meta-analysis

Background: There is no robust evidence on the contribution of reduced hamstring flexibility to the development of low back pain (LBP) in cohort studies.Purpose: To investigate whether individuals with LBP have impaired hamstring flexibility and stiffness and what measures have been used to compare hamstring flexibility and stiffness between individuals with and without LBP.Methods: A systematic literature search was undertaken in PubMed, EMBASE, MEDLINE, CINAHL, SCOPUS, and Cochrane databases from inception to April 2018. The GRADE system was used to determine the quality of evidence for each measure evaluated in meta-analysis.Results: Respectively, seventeen and two studies having acceptable methodological quality were analyzed with regard to hamstring flexibility and stiffness. Four measures were identified for hamstring flexibility and five for stiffness. Meta-analyses were undertaken in straight leg raising (SLR), sit and reach and knee extension in 90° hip flexion for hamstring flexibility and for hamstring stiffness measures of stiffness at 50° SLR and gradient of stiffness from 20° to 50° SLR (M_e-grad). Significantly reduced hamstring flexibility or increased stiffness (P < .05) was detected in SLR, 90/90 knee extension and M_e-grad. However, the validity of measures for hamstring flexibility was problematic and GRADE scores for all measures in the meta-analyses were very low.Conclusion: There have been four measures for hamstring flexibility and five for stiffness to evaluate individuals with and without LBP. It was impossible to conclude whether individuals with LBP have impaired hamstring flexibility and stiffness due to very low quality of evidence for meta-analyses.

Electron Vorticity Indicative of the Electron Diffusion Region of Magnetic Reconnection

While vorticity defined as the curl of the velocity has been broadly used in fluid and plasma physics, this quantity has been underutilized in space physics due to low time resolution observations. We report Magnetospheric Multiscale (MMS) observations of enhanced electron vorticity in the vicinity of the electron diffusion region of magnetic reconnection. On 11 July 2017 MMS traversed the magnetotail current sheet, observing tailward-to-earthward outflow reversal, current-carrying electron jets in the direction along the electron meandering motion or out-of-plane direction, agyrotropic electron distribution functions, and dissipative signatures. At the edge of the electron jets, the electron vorticity increased with magnitudes greater than the electron gyrofrequency. The out-of-plane velocity shear along distance from the current sheet leads to the enhanced vorticity. This, in turn, contributes to the magnetic field perturbations observed by MMS. These observations indicate that electron vorticity can act as a proxy for delineating the electron diffusion region of magnetic reconnection.

P32 Targeting accuracy of the neuromate robot in DBS implantation for paediatric dystonia

Objectives

To quantify the accuracy of DBS electrode implantation for movement disorder in paediatric patients utilising the neuroinspire™ software and neuromate® robot.

Design

Retrospective, single-centre, cohort study.

Subjects

Fifteen patients with dystonia (67% female; median age 11 years, range 8–18 years) underwent intervention since May 2017.

Methods

DBS procedures were planned on the neuroinspire™ software and electrodes were implanted using the Renishaw neuromate® robot and Renishaw guide tubes and secured with a dog-bone plate under general anaesthetic. Post-operative CT imaging with the intra-operative O-arm was fused to pre-operative imaging. Planned entry and target coordinates were compared to actual entry and final target coordinates in order to obtain absolute and directional errors in x (medial-lateral), y (anterior-posterior) and z (dorsal-ventral) planes. Euclidean error was calculated for each electrode. Wilcoxon signed-rank test was used to analyse error.

Results

Bilateral GPi were targeted and Medtronic DBS systems were implanted for each patient (n=30). Overall median Euclidean error for electrode implantation was 2.13 mm (range, 0.71–4.85; p<0.001). No discrepancy between left- and right-sided electrodes was seen (p=0.346). Absolute errors in x (med 1.25 mm, range 0.10–4.10), y (med 0.80 mm, range 0–2.70) and z (med 1.45 mm, range 0–3.90) planes were individually significant (p<0.001). On overall anterior displacement of leads was observed (med 0.55+0.85 mm, p=0.001) but there was no significant directional bias in x (p=0.219) or z (p=0.077) planes.

Conclusions

We observed an improvement in the discrepancy seen between planned and actual lead location compared to a previously reported series using the Leksell frame in a similar cohort. Addressing possible compounding factors such as drilling techniques and electrode fixation should increase accuracy further. The neuromate® Robot is a reliable and accurate alternative to the Leksell frame.

FM2-7 Paediatric robot-assisted DBS surgery: electrode problems and revision techniques

Objectives

We review our cases of hardware problems requiring revision surgery and consider the technical aspects of revising the electrodes, including a frameless technique using the Renishaw Guide tubes.

Design

Retrospective Review.

Subjects

Children (≤18 years old) who presented with hardware problems following implantation of a DBS for dystonia at King’s College Hospital between May 2005 and April 2018.

Methods

Information was obtained from a prospectively kept database.

Results

Of 166 paediatric patients with DBS, 25 patients had hardware problems, and of these 21 (13%) patients had specifically electrode problems requiring replacement/revision of one or more electrodes. 7 patients had high impedances requiring revision, without obvious lead migration of fracture. 7 patients had lead migration and a further 7 patients had a lead fracture with or without lead migration. 15 patients had original DBS insertion with the Leksell Stereotactic System utilising the Medtronic Stimlock for lead fixation. 6 patients had DBS inserted with the Renishaw Sterotactic Robot and utilised the Renishaw Guide Tubes, in these patients who required lead replacement it was possible to revise the electrode without using stereotactic apparatus. As the guide tubes are implanted in the correct trajectory it is possible to measure the distance required to advance/implant the lead within this to target without the need for full stereotactic reimplantation.

Conclusions

Electrode dysfunction is relatively common in children with DBS and a systematic approach is required to identify the cause. When an electrode requires repositioning or replacement, the procedure can be performed in the conventional manner with a stereotactic frame, or freehand without a frame if a Renishaw Guide tube is used at time of first insertion.

Abstract OT2-07-05: A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD)

Background: Docetaxel + Trastuzumab (H) + Pertuzumab (P) provided progression-free survival (PFS) and overall survival (OS) benefits in HER2-positive advanced or metastatic breast cancer (AMBC) in the CLEOPATRA study as a first-line therapy. However, long-term administration of docetaxel at a dose of 75 mg/m2 every 3 weeks in AMBC patients (pts) is difficult due to the toxicities. Eribulin mesylate (E) is a well-tolerated microtubule inhibitor, and we have reported the efficacy and safety of EHP regimen as first- and second-line therapy for AMBC in a multicenter, phase II study (JBCRG-M03/UMIN000012232). In this M06 study, we address the clinical question as to which is the better chemotherapy partner for HP as first line regimen, in terms of efficacy, toxicity and QOL.

Methods: JBCRG-M06 is a multicenter open-label randomized phase III study for HER2-positive AMBC pts who have received no prior chemotherapy except for the HER2- Antibody-Drug Conjugate (ADC). Pts will be randomized 1:1 to E (1.4mg/m2 on day 1 and 8) + H (8 mg/kg loading dose followed by 6 mg/kg) +P (840 mg loading dose followed by 420 mg) q3wks or standard taxanes (docetaxel 75mg/m2 on day1 or paclitaxel 80mg/m2 on day 1, 8 and 15) + HP q3wks. Stratification factors for randomization are; presence of visceral metastases, number of prior taxanes on perioperative adjuvant treatment, and treatment with prior anti-HER2-ADC. Primary endpoint is PFS and secondary endpoints include overall response rate, duration of response, OS, patient-reported outcomes (PRO) relating to QOL and peripheral neuropathy, new-metastases free survival, and safety. Translational research to search for biomarker for individual precision therapy will be performed. Main eligibility criteria are as follows: pts with HER2-positive AMBC, female aged 20-70 years old, ECOG PS of 0-1, LVEF ≥ 50% at baseline and adequate organ function. Pts who had progressive MBC within 6 months after the end of primary adjuvant systemic chemotherapy are excluded. The sample size was calculated by type1 error (2-sided) of 0.05 and 80% power to estimate the noninferiority margin 1.33 with an expected median PFS of 14.2 months. The target number of pts is 480 recruited over the duration of 3-years. The first patient in was achieved on August 2017. (ClinicalTrials.gov Identifier:NCT03264547).

Citation Format: Masuda N, Yamashita T, Saji S, Araki K, Ito Y, Takano T, Takahashi M, Tsurutani J, Koizumi K, Kitada M, Kojima Y, Sagara Y, Tada H, Iwasa T, Kadoya T, Iwatani T, Hasegawa H, Morita S, Ohno S. A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-07-05.

Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars

Spherical Fe-oxide concretions on Earth, especially in Utah, USA, have been investigated as an analog of hematite spherules found in Meridiani Planum on Mars to support interpretations of water-rock interactions in early Mars. Although several formation mechanisms have been proposed for the Fe-oxide concretions on Earth, it is still unclear whether these mechanisms are viable because a precise formation process and precursor of the concretions are missing. This paper presents evidence that Fe-oxide concretions in Utah and newly found Fe-oxide concretions in Mongolia had spherical calcite concretions as precursors. Different formation stages of calcite and Fe-oxide concretions observed, both in Utah and Mongolia, indicate that calcite concretions initially formed within eolian sandstone strata and were dissolved by infiltrating Fe-rich acidic waters to form spherical FeO(OH) crusts due to pH buffering. The similarity between these Fe-oxide concretions on Earth and the hematite spherule occurrences in Meridiani Planum, combined with evidence of acid sulfate water influences on Mars, suggest that the hematite spherules also formed from dissolution of preexisting carbonate spherules possibly formed under a dense carbon dioxide early martian atmosphere.

Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma

Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth's magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He⁺ to energies up to ~2 kilo-electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.

Integrating 3D Rotational Angiography into Gamma Knife Planning

3D rotational angiography provides remarkable spatial resolution for cerebrovascular disorders; however, it cannot be integrated directly into gamma knife planning due to the discrepancy of DICOM "tag" information, and most physicians still cannot benefit from 3D rotational angiography. Here, we describe a simple and easy technique to enable the integration of 3D rotational angiography.

Site-specific Chemotherapy Based on Predicted Primary Site by Pathological Profile for Carcinoma of Unknown Primary Site

AIMS

Although platinum-based combination chemotherapies are commonly used for unfavourable subsets of cancer of unknown primary (CUP), the prognosis remains poor. Several studies have suggested that gene expression profiling or immunohistochemistry was useful for the prediction of primary sites in CUP, and site-specific therapy based on predicted primary sites might improve overall outcomes. In Japan, to identify primary sites, immunohistochemical tests were commonly used for CUP in clinical practice. However, it is unclear whether site-specific therapy based on predicted primary sites by pathological examination contributes survival benefit for unfavourable CUP subsets.

PATIENTS AND METHODS

In this study, 122 patients with unfavourable subsets of CUP were retrospectively reviewed. Ninety patients assigned to cohort A after July 2012 had received chemotherapy according to predicted primary sites; 32 patients assigned to cohort B before June 2012 had received platinum-based empiric chemotherapy.

RESULTS

In cohort A, 56 patients (62.2%) with predicted primary sites by pathological examination received site-specific therapy; 34 patients (37.8%) with unpredictable primary sites received platinum-based empiric chemotherapy, the same as cohort B. The median overall survival was 20.3 months in patients with predictable primary sites in cohort A and 10.7 months in those of cohort B, with a significant difference between these cohorts (P = 0.03, adjusted hazard ratio = 0.57, 95% confidence interval 0.34-0.94).

CONCLUSION

Site-specific therapy based on predicted primary sites by pathological examination could improve prognosis in patients with an unfavourable subset of CUP.

Analysis of the Disappearance Curve of Labelled Fibrinogen at the Time of Hyperfibrinogenemia in Rabbits with Acute or Chronic Intravascular Coagulation

In order to study fibrinogen metabolism, the disappearance curve of 125I-labelled homologous fibrinogen was investigated in the rabbits with experimentally induced acute or chronic intravascular coagulation by injection of Lycopodium spores or thromboplastin. The results obtained were as follows.

1. Using haemolysate, an intermediate phase with upward convexity was clearly recognized between the early rapid-decay phase and the late slow phase in each radioactivity decay curve obtained in groups of rabbits. This convexity was most marked with acute intravascular coagulation induced by injection of Lycopodium spores, and was less marked, although higher, with chronic intravascular coagulation induced by injection of thromboplastin than that in the normal control.

2. The disappearance curve with the intermediate phase could be expressed, in approximation, as a sum of 2 equations - the initial exponential decay equation and the late parabolic one.

3. From the results obtained by separate examinations of the disappearance curve of plasma, fibrin clots and serum in rabbits with acute intravascular coagulation induced by injection of Lycopodium spores, the intermediate phase appears to be influenced more by the secondary increase of labelled non-clottable part than recirculation of the labelled fibrinogen.

4. The half time (27.4 hours) of the radioactivity in fibrin clots at the late phase observed in the group of rabbits with acute intravascular coagulation induced by injection of Lycopodium spores was shorter than that in the normal rabbits (50.2 hours). This fact may indicate that the increase of fibrinogen in the group of rabbits with acute intravascular coagulation induced by the injection of Lycopodium spores is due to overproduction of fibrinogen.

5. The half time of labelled fibrinogen should be calculated from disappearance curve of fibrin clots, instead from that of haemolysate or plasma.

Structural and transport properties of neutral radical crystals of CoIII(tmp)(CN)2 (tmp = 5,10,15,20-tetramethylporphyrinato) and the CN-bridged polymer [CoIII(tmp)(CN)]n

An axially ligated Co(tmp) (tmp = 5,10,15,20-tetramethylporphyrinato) anion, [Co^III(tmp)(CN)₂]^-, has been prepared and subjected to electrochemical oxidation to obtain the open shell tmp π-ligand. With acetone as the solvent, solvent-free neutral radical crystals of Co^III(tmp)(CN)₂ are obtained, whereas solvent-inclusive crystals of Co^III(tmp)(CN)₂·2CH₃CN are obtained with CH₃CN as the solvent. In both crystals, the open shell tmp ring deforms into a ruffled form, which makes the π-π interactions in the crystal weak. Thus, the electrical conductivity is low, and the crystals behave as semiconductors with a room temperature resistivity of 10⁶ Ω cm and an activation energy of about 0.3 eV. When the solvent is acetone, non-oxidized crystals of the CN-bridged polymer {[Co^III(tmp)(CN)](acetone)}_n are obtained as a byproduct. The closed shell tmp ring deforms into a ruffled form, and there π-π interactions in the crystal are negligible. The room temperature resistivity is rather high at about 10⁸ Ω cm.