Protein nanoarrays using the annexin A5 two-dimensional crystal on supported lipid bilayers

Protein nanoarrays are regularly ordered patterns of proteins fixed on a solid surface with a periodicity on the order of nanometers. They have significant potential applications as highly sensitive bioassays and biosensors. While several researchers have demonstrated the fabrication of protein nanoarrays with lithographic techniques and programmed DNA nanostructures, it has been difficult to fabricate a protein nanoarray containing a massive number of proteins on the surface. We now report the fabrication of nanoarrays of streptavidin molecules using a two-dimensional (2D) crystal of annexin A5 as a template on supported lipid bilayers that are widely used as cell membranes. The 2D crystal of annexin A5 has a six-fold symmetry with a period of about 18 nm. There is a hollow of a diameter of about 10 nm in the unit cell, surrounded by six trimers of annexin A5. We found that a hollow accommodates up to three streptavidin molecules with their orientation controlled, and confirmed that the molecules in the hollow maintain their specific binding capability to biotinylated molecules, which demonstrates that the fabricated nanoarray serves as an effective biosensing platform. This methodology can be directly applied to the fabrication of nanoarrays containing a massive number of any other protein molecules.

Structured Water Molecules on Membrane Proteins Resolved by Atomic Force Microscopy

Water structuring on the outer surface of protein molecules called the hydration shell is essential as well as the internal water structures for higher-order structuring of protein molecules and their biological activities in vivo. We now show the molecular-scale hydration structure measurements of native purple membrane patches composed of proton pump proteins by a noninvasive three-dimensional force mapping technique based on frequency modulation atomic force microscopy. We successfully resolved the ordered water molecules localized near the proton uptake channels on the cytoplasmic side of the individual bacteriorhodopsin proteins in the purple membrane. We demonstrate that the three-dimensional force mapping can be widely applicable for molecular-scale investigations of the solid-liquid interfaces of various soft nanomaterials.

A preliminary study of the safety and effectiveness of isoproterenol loading transesophageal echocardiography in atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

In patients with sludge or severe spontaneous echo contrast (SEC) in the left atrial appendage (LAA), isoproterenol loading transesophageal echocardiography (ISP-TEE) has been reported to check the presence of thrombus in the LAA, as the sludge or severe SEC disappears (Figure 1).

Purpose

The aim of this study was to assess the safety of ISP-TEE for the identification of LAA thrombus and the hemodynamic changes in the LAA caused by ISP loading.

Methods

We prospectively enrolled 25 patients with atrial fibrillation (AF) and sludge or SEC in the LAA who underwent ISP-TEE from April 2020 to July 2021. ISP was administered intravenously to achieve the target heart rate (HR) defined as follows: Max HR [beats per minutes: bpm] = 220 – age (years), Target HR [bpm] = Max HR × 0.8. Patients with tachycardia exceeding Max HR before ISP administration, hemodynamic instability, and other contraindications to ISP were excluded from the study. To assess the safety of ISP-TEE, we evaluated patients’ condition, changes in systolic blood pressure (sBP) and HR before and after ISP loading. We also assessed the presence or absence of worsening heart failure, new arrhythmias other than atrial fibrillation, and cerebral infarction or transient ischemic attack during the examination, and after 24 hours. Hemodynamic evaluation was performed using LAA blood flow velocity, LAA tissue Doppler imaging (TDI) velocity, and LAA volume fraction (LAAVF) defined as follows: LAAVF (%) = (Max LAA volume – Min LAA volume) / Max LAA volume × 100. Quantification of LAA volume was performed using the stacked-contour method of a 3-dimensional TEE full-volume acquisition.

Results

Among 25 patients, 13 patients had sludge or grade3 SEC, 7 patients had grade2 SEC, 5 patients had grade1 SEC. HR after ISP loading was significantly higher than before loading, but sBP did not change significantly before and after ISP loading. No complications due to ISP loading were observed during examination and after 24 hours. After ISP loading, there were 18 patients with grade 1 SEC or no SEC (classified as Group1), 7 patients had residual sludge or grade 2 to 3 SEC (classified as Group2). The differences in LAA blood flow velocity between before and after ISP loading was faster in Group1 than in Group2: 13.0 ± 10.5 vs 2.6 ± 4.2. p = 0.019. The differences in TDI velocity was also faster in Group1 than in Group2: 1.46 ± 1.14 vs 0.19 ± 0.50, p = 0.010. The differences in LAAVF was higher in Group1 than in Group2: 13.7 ± 10.3 vs 2.2 ± 2.0, p = 0.009.

Conclusions

In our study, no complications were observed in ISP-TEE for the identification of LAA thrombus. Patients with grade 1 SEC or no SEC, the LAA function was increased by ISP loading. These results may provide insights into the mechanisms of ISP loading on SEC in the LAA. Abstract Figure.

β-hydroxybutyrate suppresses NLRP3 inflammasome-mediated placental inflammation and lipopolysaccharide-induced fetal absorption

The immune system contributes to the regulation of pregnancy, and the disruption of well-controlled immune functions leads to pregnancy complications. Recently, the nucleotide-binding oligomerization domain, leucine-rich repeat-, and pyrin domain-containing 3 (NLRP3) inflammasome mechanisms [(a protein complex of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and caspase-1)] have been reported to play roles in controlling placental inflammation involved in pregnancy pathologies. The ketone body β-hydroxybutyrate (BHB) can suppress NLRP3 inflammasome activation and improve various inflammatory diseases. Therefore, we hypothesized that BHB could suppress activation of the NLRP3 inflammasome in the placenta, resulting in the improvement of pregnancy complications. In human placental tissue culture, treatment with BHB suppressed the secretion levels of inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and IL-8, but did not affect the mRNA expression levels of NLRP3 inflammasome-associated factors. Treatment with BHB reduced IL-1β secretion and the amount of mature IL-1β protein induced by lipopolysaccharide (LPS) stimulation in the placenta. In human trophoblast cells, BHB reduced ASC and activated-caspase-1 expression, resulting in the inhibition of IL-1β secretion. To investigate the effect of BHB during pregnancy, we used an animal model of LPS (100 μg/kg intraperitoneally [i.p.] on gestational day 14)-induced pregnancy complications. Administration of BHB (100 mg/kg i.p.) clearly suppressed the absorption rate and IL-1β production in the placenta induced by LPS in pregnant mice. Moreover, LPS-induced pregnancy abnormalities were improved in NLRP3-deficient mice. These findings suggest that BHB play a role in reducing placental inflammation and pregnancy complications via inhibition of NLRP3 inflammasome activation.

Advanced maternal age induces fetal growth restriction through decreased placental inflammatory cytokine expression and immune cell accumulation in mice

Advanced maternal age is a risk factor for female infertility, and placental dysfunction is considered one of the causes of pregnancy complications. We investigated the effects of advanced maternal aging on pregnancy outcomes and placental senescence. Female pregnant mice were separated into three groups: young (3 months old), middle (8–9 months old), and aged (11–13 months old). Although the body weights of young and middle dams gradually increased during pregnancy, the body weight of aged dams only increased slightly. The placental weight and resorption rate were significantly higher, and live fetal weights were reduced in a maternal age-dependent manner. Although mRNA expression of senescence regulatory factors (p16 and p21) increased in the spleen of aged dams, mRNA expression of p16 did not change and that of p21 was reduced in the placenta of aged dams. Using a cytokine array of proteins extracted from placental tissues, the expression of various types of senescence-associated secretory phenotype (SASP) factors was decreased in aged dams compared with young and middle dams. The aged maternal placenta showed reduced immune cell accumulation compared with the young placenta. Our present results suggest that models using pregnant mice older than 8 months are more suitable for verifying older human pregnancies. These findings suggest that general cellular senescence programs may not be included in the placenta and that placental functions, including SASP production and immune cell accumulation, gradually decrease in a maternal age-dependent manner, resulting in a higher rate of pregnancy complications.

Deficiency of the RIβ subunit of protein kinase A causes body tremor and impaired fear conditioning memory in rats

The RIβ subunit of cAMP-dependent protein kinase (PKA), encoded by Prkar1b, is a neuronal isoform of the type I regulatory subunit of PKA. Mice lacking the RIβ subunit exhibit normal long-term potentiation (LTP) in the Schaffer collateral pathway of the hippocampus and normal behavior in the open-field and fear conditioning tests. Here, we combined genetic, electrophysiological, and behavioral approaches to demonstrate that the RIβ subunit was involved in body tremor, LTP in the Schaffer collateral pathway, and fear conditioning memory in rats. Genetic analysis of WTC-furue, a mutant strain with spontaneous tremors, revealed a deletion in the Prkar1b gene of the WTC-furue genome. Prkar1b-deficient rats created by the CRISPR/Cas9 system exhibited body tremor. Hippocampal slices from mutant rats showed deficient LTP in the Schaffer collateral-CA1 synapse. Mutant rats also exhibited decreased freezing time following contextual and cued fear conditioning, as well as increased exploratory behavior in the open field. These findings indicate the roles of the RIβ subunit in tremor pathogenesis and contextual and cued fear memory, and suggest that the hippocampal and amygdala roles of this subunit differ between mice and rats and that rats are therefore beneficial for exploring RIβ function.

Deep learning for screening of pulmonary hypertension using standard chest X-ray

Background

Early detection of pulmonary hypertension (PH) is crucial to ensure that patients receive timely treatment for the progressive clinical course. The chest X-ray (CXR), a routine method at hospitals, has recommended in order to reveal features supportive of a diagnosis of PH. However, it is well known that the sensitivity and specificity are low.

Purpose

We tested the hypothesis that application of artificial intelligence (AI) to the CXR could identify PH.

Methods

We retrospectively enrolled 900 data with paired CXR and right heart catheter (RHC), including the pulmonary artery pressure, from October 2009 to December 2018. We trained a convolutional neural network to identify patients with PH as actual value of pulmonary artery pressure, using the CXR alone (Figure). The diagnosis of PH was performed using hemodynamic measurements according to the most recent World Symposium standards: mean PAP ≥20 mmHg. We have compared the area under the curve (AUC) by human observers, measurements of CXR images, and AI for detection of PH.

Results

Subjects were divided into two groups with PH (439 patients; mean age, 66±14 years; 233 male) and without PH (461 patients; mean age, 68±12 years; 278 male). In an independent set, AI was the highest diagnostic ability for detection of PH (AUC: 0.71). The AUC by the AI algorithm was significantly higher than the AUC by measurements of CXR images and human observers (0.71 vs. 0.60 and vs. 0.63, all compared p<0.05).

Conclusion

Applying AI to the CXR (a classical, universal, low-cost test) permits the CXR images to serve as a powerful tool to screen for PH.

Neural network

Funding Acknowledgement

Type of funding source: None

540 Assessment of left ventricular ejection fraction from echocardiographic images using machine learning algorithm

Background

Precise and reliable echocardiographic assessment of LVEF is needed for clinical decision-making. LVEF is currently determined through an observer dependent process that requires manual tracing. To remove this manual tracing step, which is both time-consuming and user dependent, automatic computer aided diagnosis systems may be useful in the clinical setting.

Purpose

The aim of this study was to evaluate whether a 3-dimensional convolutional neural networks (3DCNN) could estimate left ventricular ejection fraction (LVEF) and differentiate types of heart failure (preserved EF/reduced EF) using conventional 2-dimensional echocardiographic images.

Methods

We developed a deep learning model to automatically estimate LVEF from echocardiographic data. The 3DCNN model was trained on a dataset of 340 patients. The dataset creation consisted of three main steps: firstly, for each exam, cine-loops showing the parasternal and apical views were manually selected; then, 10 sequential frames were extracted from each 1 beat and; finally, each frame was pre-processed to fit the learning model. Each patient has 2 views, resulting in a total of 6,800 images. Reference LVEF measurement was calculated by two highly experienced readers in each case.

Results

A good correlation was found between estimated LVEF based on apical 2 and 4 chamber views and reference LVEF (r =0.88, p <0.001) (Figure). For classification of heart failure types based on LVEF (LVEF ≥50% or <50%), the area under the receiver-operating characteristic curve by the 3DCNN algorithm was over 0.95.

Conclusions

The 3DCNN can be applied to estimate and classify the LVEF in the clinical setting. Furthermore, this work will serve as a driver for future research using million image databases.

Abstract 540 Figure.

P1526 Updated prevalence of lambls excrescences using the latest three-dimensional transesophageal echocardiography

Background

Lambl’s excrescences (LEs), filiform strands that occur at sites of cardiac valves, have been suggested the cause cryptogenic stroke. The diagnosis is primarily based upon the echocardiographic study, but conventional two-dimensional transthoracic echocardiography has limitation to detect such as small strands. Latest three dimensional-transesophageal echocardiography (3D-TEE) have high-resolution images with many slices, so small structures are able to be clearly visible and detected.

Purpose

The aim of this study was to assess the prevalence of LEs using the latest 3D-TEE images.

Methods

We retrospectively reviewed consecutive 140 patients who underwent 3D-TEE from November 2018 to May 2019. Forty-seven patients were excluded due to unmeasurable, such as mitral valve prolapse, severe aortic stenosis, prosthetic valves and poor-quality images. We carefully evaluated the mitral and aortic valve leaflets in order to find mobile string structure (diameter <1 mm and length 1–20 mm) in each cardiac cycle. Total analyzed images were over 50 slices per one patient.

Results

Among 93 patients, 83 patients (89%) was detected the presence of LEs. No difference in age and gender were found between patients with LEs and patients without LEs. Of the total 83 patients, there were 35 patients with strands on mitral valve, 32 patients with strands on aortic valve, and 16 patients with strands on both valves. Distribution of LEs at each valve leaflet were shown in Figure. Right coronary cusp of aortic valve (42%) and P2 of mitral valve (35%) were high prevalence among leaflets.

Conclusions

3D-TEE provides an update prevalence of LEs. The prevalence of LEs might be potentially high in the real world.

Abstract P1526 Figure.

Transition of Spleen Volume Long After Pediatric Living Donor Liver Transplantation for Biliary Atresia

PURPOSE

After undergoing the Kasai procedure for biliary atresia (BA), most patients develop severe splenomegaly that tends to be improved by liver transplantation. However, fluctuations in splenic volume long after transplantation remain to be elucidated.

PATIENTS AND METHODS

Seventy-one consecutive patients who had undergone pediatric living donor liver transplantation (LDLT) for BA were followed up in our outpatient clinic for 5 years. They were classified into 3 groups according to their clinical outcomes: a good course group (GC, n = 41) who were maintained on only 1 or without an immunosuppressant, a liver dysfunction group (LD, n = 18) who were maintained on 2 or 3 types of immunosuppressants, and a vascular complication group (VC, n = 11). Splenic and hepatic volumes were calculated by computed tomography in 464 examinations and the values compared before and after the treatment, especially in the VC group.

RESULTS

Splenic volume decreased exponentially in the GC group, with splenic volume to standard spleen volume ratio (SD) being 1.59 (0.33) 5 years after liver transplantation. Splenic volume to standard spleen volume ratios were greater in the VC and LD groups than in the GC group. Patients in the VC group with portal vein stenosis developed liver atrophy and splenomegaly, whereas those with hepatic vein stenosis developed hepatomegaly and splenomegaly. Interventional radiation therapy tended to improve the associated symptoms.

CONCLUSIONS

Fluctuations in splenic volume long after pediatric LDLT for BA may reflect various clinical conditions. Evaluation of both splenic and hepatic volumes can facilitate understanding clinical conditions following pediatric LDLT.

Simulation training for medical emergencies in the dental setting using an inexpensive software application

INTRODUCTION

Every dental provider needs to be educated about medical emergencies to provide safe dental care. Simulation training is available with simulators such as advanced life support manikins and robot patients. However, the purchase and development costs of these simulators are high. We have developed a simulation training course on medical emergencies using an inexpensive software application. The purpose of this study was to evaluate the educational effectiveness of this course.

MATERIALS AND METHODS

Fifty-one dental providers participated in this study from December 2014 to March 2015. Medical simulation software was used to simulate a patient's vital signs. We evaluated participants' ability to diagnose and treat vasovagal syncope or anaphylaxis with an evaluation sheet and conducted a questionnaire before and after the scenario-based simulation training.

RESULTS

The median evaluation sheet score for vasovagal syncope increased significantly from 7/9 before to 9/9 after simulation training. The median score for anaphylaxis also increased significantly from 8/12 to 12/12 (P < .01). For the item "I can treat vasovagal syncope/anaphylaxis adequately," the percentage responding "Strongly agree" or "Agree" increased from 14% to 56% for vasovagal syncope and from 6% to 42% for anaphylaxis with simulation training.

CONCLUSIONS

This simulation course improved participants' ability to diagnose and treat medical emergencies and improved their confidence. This course can be offered inexpensively using a software application.

Electronic Structure of Ce-Doped and -Undoped Nd_{2}CuO_{4} Superconducting Thin Films Studied by Hard X-Ray Photoemission and Soft X-Ray Absorption Spectroscopy

In order to realize superconductivity in cuprates with the T^{'}-type structure, not only chemical substitution (Ce doping) but also postgrowth reduction annealing is necessary. In the case of thin films, however, well-designed reduction annealing alone without Ce doping can induce superconductivity in the T^{'}-type cuprates. In order to unveil the origin of superconductivity in the Ce-undoped T^{'}-type cuprates, we have performed bulk-sensitive hard x-ray photoemission and soft x-ray absorption spectroscopy on superconducting and nonsuperconducting Nd_{2-x}Ce_{x}CuO_{4} (x=0, 0.15, and 0.19) thin films. By postgrowth annealing, core-level spectra exhibited dramatic changes, which we attributed to the enhancement of core-hole screening in the CuO_{2} plane and the shift of chemical potential along with changes in the band filling. The result suggests that the superconducting Nd_{2}CuO_{4} film is doped with electrons despite the absence of the Ce substitution.

Element Selectivity in Second-Harmonic Generation of GaFeO_{3} by a Soft-X-Ray Free-Electron Laser

Nonlinear optical frequency conversion has been challenged to move down to the extreme ultraviolet and x-ray region. However, the extremely low signals have allowed researchers to only perform transmission experiments of the gas phase or ultrathin films. Here, we report second harmonic generation (SHG) of the reflected beam of a soft x-ray free-electron laser from a solid, which is enhanced by the resonant effect. The observation revealed that the double resonance condition can be met by absorption edges for transition metal oxides in the soft x-ray range, and this suggests that the resonant SHG technique can be applicable to a wide range of materials. We discuss the possibility of element-selective SHG spectroscopy measurements in the soft x-ray range.

Tensile-Strain-Dependent Spin States in Epitaxial LaCoO_{3} Thin Films

The spin states of Co^{3+} ions in perovskite-type LaCoO_{3}, governed by the complex interplay between the electron-lattice interactions and the strong electron correlations, still remain controversial due to the lack of experimental techniques which can directly detect them. In this Letter, we revealed the tensile-strain dependence of spin states, i.e., the ratio of the high- and low-spin states, in epitaxial thin films and a bulk crystal of LaCoO_{3} via resonant inelastic soft x-ray scattering. A tensile strain as small as 1.0% was found to realize different spin states from that in the bulk.

Endotoxin Metabolism Reflects Hepatic Functional Reserve in End-Stage Liver Disease

BACKGROUND

The hepatic clearance of endotoxin (Et) may reflect hepatic functional reserve and ischemic injury to hepatocytes. Therefore, we examined the relationships between Et activity (EA) and the metrics Pediatric End-Stage Liver Disease (PELD)/Model of End-Stage Liver Disease (MELD) score and alanine transaminase (ALT) levels in the postoperative period.

METHODS

We performed 8 living-donor liver transplantations (LDLTs) for biliary atresia at our center from April 2012 to December 2012. EA was measured by means of an Et activity assay (EAA) in samples collected from a vein 1 day before LDLT, from the portal vein during the intraoperative anhepatic phase, from an artery 1 hour after reperfusion, from an artery on postoperative day (POD) 1, and from an artery or vein at PODs 7 and 14.

RESULTS

EAs generally remained at low levels. EA at the reperfusion period was significantly lowest. The correlation coefficient for the preoperative MELD/PELD score and the EAA was 0.837, and the corresponding P value was .009; thus, there was a significant relationship between the preoperative MELD/PELD score and the EAA. The correlation coefficients for ALT at POD 1 and EA during the anhepatic phase, at 1 hour after reperfusion, and at POD 1 were 0.64, 0.43, and 0.38, respectively, and the P values for these correlations were .08, .67, and .34. Thus, we observed that ALT and EA generally tended to be somewhat directly correlated, but no significant relationships between these 2 metrics were observed.

CONCLUSIONS

Endotoxin metabolism reflects the hepatic functional reserve capacity of end-stage liver disease.

Antibody Drug Treatment for Steroid-Resistant Rejection After Pediatric Living Donor Liver Transplantation: A Single-Center Experience

BACKGROUND

Antibody drugs have been used to treat steroid-resistant rejection (SRR) after liver transplantation. Although anti-thymocyte globulin has been used for SRR after liver transplantation in place of muromonab-CD3 since 2011 in Japan, the effectiveness of anti-thymocyte globulin after pediatric living-donor liver transplantation (LDLT) has not yet been reported. The aim of this study was to evaluate the effectiveness of antibody drug treatment for SRR after pediatric LDLT in our single center.

METHODS

Between May 2001 and December 2013, 220 pediatric LDLTs were performed. Initial immunosuppression after LDLT included tacrolimus and methylprednisolone therapy. Acute rejection was diagnosed by use of a liver biopsy and the administration of steroid pulse treatment, and SRR was defined as acute rejection refractory to the steroid pulse treatment.

RESULTS

Acute rejection and SRR occurred in 74 (33.6%) and 16 patients (7.3%), respectively. The graft survival rates of non-SRR and SRR were 92.4% and 87.5%, respectively (P = .464). The median concentration of alanine aminotransferase before and after the administration of antibody drug was 193.5 mU/mL (range, 8-508) and 78 mU/mL (range, 9-655), respectively (P = .012). The median rejection activity index before and after the administration of antibody drugs was 5 (range, 2-9) and 1 (range, 0-9), respectively (P = .004). After antibody drug treatment, 12 patients had cytomegalovirus infections, 2 patients had Epstein-Barr virus infections, 3 patients had respiratory infections, and 1 patient had encephalitis. The cause of death in 1 patient with SRR was recurrence of infant fulminant hepatic failure.

CONCLUSIONS

Antibody drug treatment for SRR after pediatric LDLT is safe and effective.

Properties of modified surface for biosensing interface

Properties of modified surface, behavior against salting-out effect, suppressive effect for protein nonspecific adsorption, and wettability were examined using various mercapto compounds bearing methyloligoethylene glycol, oligoethylene glycol, alkyl oligoethylene glycol, alkyl phosphoryl choline, alkyl inverse phosphoryl choline, and alkyl sulfobetaine moieties. The behavior against salting-out effect was examined using gold nanoparticle with PBS and NaCl aqueous solution. The suppressive effect for protein nonspecific adsorption was evaluated by SPR, and the wettability was measured on the SPR chip. The gold nanoparticle modified with 8C3EG, 12C4EG, 12CPC, 6CCP, and 12CCP showed excellent behavior against salting-out effect. The suppression of protein nonspecific adsorption was effective with 6EG, 12C4EG, 12CPC, and 12CS. On the other hand, the modified surface possessed high wettability except for the surface modified with M6EG. The results indicate that incorporation of alkyl group into surface modification materials is effective for the enhancement of behavior against salting-out effect and suppressive effect for protein nonspecific adsorption regardless of wettability. Among the zwitter ionic derivatives, inverse phosphoryl choline derivatives showed intriguing properties, high behavior against salting-out effect with high wettability but low suppressive effect for protein nonspecific adsorption.

Relationship Between Graft Liver Function and the Change of Graft Liver and Spleen Volumes After Technical Variant Liver Transplantation

BACKGROUND

Although there have been a few reports describing the changes of graft liver and spleen volumes after liver transplantation (LT), little is known about the relationship between graft liver function and the changes of these volumes after technical variant liver transplantation (TVLT). We therefore performed a retrospective study to investigate the relationship between graft liver function and these volumes after TVLT.

METHODS

We retrospectively investigated the cases of 140 TVLT procedures that were performed in our department between July 1987 and October 2012 and in which follow-up was conducted at our department. We calculated the graft liver volume to standard liver volume (GV/SLV) ratio, the spleen volume to standard spleen volume (SV/SSV) ratio, and the spleen volume to graft liver volume (S/L) ratio by CT volumetry. We clarified the relationship between graft liver function (according to the pathological findings) and the graft liver and spleen volumes at 2, 5, and 10 years after TVLT.

RESULTS

In the normal liver function group, the GV/SLV, SV/SSV, and S/L ratios decreased until 6 months after TVLT and then converged at 10 years after TVLT to 0.95, 1.27, and 0.27, respectively. In the graft liver failure group, the GV/SLV, SV/SSV, and S/L ratios at 10 years after TVLT were 0.67, 5.01, and 1.55, respectively. A significant correlation was observed between the GV/SLV ratio and the presence of mild liver fibrosis at 2 and 5 years after TVLT (P = .03 and P = .04, respectively).

CONCLUSIONS

Post-transplant CT-volumetry is a noninvasive and effective means of evaluating graft liver status.

Total internal biliary diversion during liver transplantation for type 1 progressive familial intrahepatic cholestasis: a novel approach

LT for PFIC type 1 is often complicated by postoperative diarrhea and recurrent graft steatosis. A 26-month-old female child with cholestatic jaundice, pruritus, diarrhea, and growth retardation revealed total bilirubin 9.1 mg/dL, gamma-glutamyl transpeptidase 64 IU/L, and TBA 295.8 μmol/L. Genetic analysis confirmed ATP8B1 defects. A LT (segment 2, 3 graft) from the heterozygous father was performed. Biliary diversion was performed by a 35-cm jejunum conduit between the graft hepatic duct and the mid-transverse colon. Stools became pigmented immediately. Follow-up at 138 days revealed resolution of jaundice and pruritus and soft-to-hard stools (6-8 daily). Radioisotope hepato-biliary scintigraphy (days 26, 68, and 139) confirmed unobstructed bile drainage into the colon (t_1/2 34, 27, and 19 minutes, respectively). Contrast meal follow-through at day 62 confirmed the absence of any colo-jejuno-hepatic reflux. At 140 days, contrast follow-through via the biliary stent revealed patent jejuno-colonic anastomosis and satisfactory transit. Graft biopsy at LT, 138 days, and 9 months follow-up revealed comparable grades of macrovesicular steatosis (<20%). TIBD during LT may be a clinically effective stoma-free biliary diversion and may prevent recurrent graft steatosis following LT for PFIC type 1.

Age-related decline of cerebral oxygen metabolism in normal population detected with positron emission tomography

Using positron emission tomography (PET), cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured in 32 healthy volunteers aged from 27 to 67 years. In bilateral putamen, left supratemporal, left infrafrontal and left parietal cortices, CMRO2 showed a significant decline during aging. The age-related decline of CBF was seen only at the left superior temporal cortex. The mean CMRO2 was significantly lower in the elder group (over 51 years old) than in the younger group (under 50 years old), whereas no significant difference in mean CBF between the two groups. The poor correlation of CBF to the age could be explained partly by the fact that CBF is easily influenced by the physiological, psychological and/or environmental factors. The age-related changes of CMRO2 were more marked in the association cortices of the left hemisphere than in that of the right hemisphere.

Perception and Production of Singleton and Geminate Stops in Japanese: Implications for the Theory of Acoustic Invariance

The theory of relational acoustic invariance claims that there are stable acoustic properties in speech signals that correspond to a phonological feature, and that the perception system utilizes these acoustic properties for stable perception of a phoneme. The present study examines whether such an invariance exists in native listeners' perception of Japanese singleton and geminate stops despite variability in speaking rate and word length, and whether this perception corresponds to production. Native Japanese listeners identified singleton and geminate stops in continua of 3- and 4-mora words spoken at different speaking rates. Results indicated that the perception boundary is well predicted by a linear function with two variables: durations of stop closure and the (C)V(C)CV portion (with the contrasting stops underlined) of the 3- and 4-mora words. In addition, these two variables were in a consistent relationship for both perception and production of words containing 2-4 moras. The results support the relational acoustic invariance theory.

Enzyme and Mediator-coadsorbed Carbon Felt Electrode for Electrochemical Detection of Glucose Covered with Polymer Layers Based on Layer-by-Layer Technique

Glucose dehydrogenase (GlDH) and ferrocene were coadsorbed on a carbon felt (CF) sheet (5 × 10 mm, 2 mm thickness), which was used to construct an electrode for the electrochemical detection of glucose. A potential of +0.3 V vs. Ag/AgCl was applied on the base CF, and the current was measured. After the addition of glucose, the current increased and reached a steady state within 50 s. The current response was proportional to the glucose concentration up to 20 μM, with a lower detection limit of 1 μM. The surface of the CF electrode was covered by layers of polystyrene sulfonate and poly-L-lysine using layer-by-layer technique. Again the current response was proportional to glucose concentration up to 20 μM, with a lower detection limit of 2 μM. The oxidation current owing to electrochemical interferents such as L-ascorbate and acetaminophen was 1/8 times of the current observed on the unprotected electrode. In addition, the protection imparted stability to the electrode. Our work demonstrates that a GlDH/ferrocene CF electrode, protected with polystyrene sulfonate and poly-L-lysine, could be used for the electrochemical detection of glucose.

Natural history of bleeding risk in colonic diverticulosis patients: a long-term colonoscopy-based cohort study

BACKGROUND

The natural history of bleeding risk from colonic diverticulosis remains unclear.

AIM

To identify the incidence of bleeding in colonic diverticulosis patients and associated risk factors.

METHODS

A cohort of 1514 patients with colonoscopy-confirmed asymptomatic diverticulosis was selected between 2001 and 2013. Age, sex and location of colonic diverticulosis (right or left side, or bilateral) were assessed. The endpoint was a bleeding event, and data were censored at the time of last colonoscopy. The cumulative and overall incidences of bleeding were estimated using the Kaplan-Meier and person-years methods. The Cox proportional hazards model was used to estimate age- and sex-adjusted hazard ratios (aHRs).

RESULTS

The median follow-up period was 46 months. Bleeding events occurred in 35 patients, and the median time-to-event interval was 50 months. Kaplan-Meier analysis showed that the cumulative incidence of diverticular bleeding was 0.21% at 12 months, 2.2% at 60 months and 9.5% at 120 months. By the person-years method, the overall incidence rate of bleeding was 0.46 per 1000 patient-years. On multivariate analysis, age ≥70 (aHR. 3.7) and bilateral diverticulosis (aHR, 2.4) were significant risk factors for bleeding.

CONCLUSIONS

This long-term follow-up study demonstrated that the cumulative incidence of bleeding from diverticulosis was approximately 2% at 5 years and 10% at 10 years, and the overall incidence was 0.46 per 1000 patient-years. Bilateral diverticulosis increased the risk of bleeding.

Effects of rotational acetabular osteotomy on the mechanical stress within the hip joint in patients with developmental dysplasia of the hip

In this study we used subject-specific finite element analysis to investigate the mechanical effects of rotational acetabular osteotomy (RAO) on the hip joint and analysed the correlation between various radiological measurements and mechanical stress in the hip joint.

We evaluated 13 hips in 12 patients (two men and ten women, mean age at surgery 32.0 years; 19 to 46) with developmental dysplasia of the hip (DDH) who were treated by RAO.

Subject-specific finite element models were constructed from CT data. The centre–edge (CE) angle, acetabular head index (AHI), acetabular angle and acetabular roof angle (ARA) were measured on anteroposterior pelvic radiographs taken before and after RAO. The relationship between equivalent stress in the hip joint and radiological measurements was analysed.

The equivalent stress in the acetabulum decreased from 4.1 MPa (2.7 to 6.5) pre-operatively to 2.8 MPa (1.8 to 3.6) post-operatively (p < 0.01). There was a moderate correlation between equivalent stress in the acetabulum and the radiological measurements: CE angle (R = –0.645, p < 0.01); AHI (R = –0.603, p < 0.01); acetabular angle (R = 0.484, p = 0.02); and ARA (R = 0.572, p < 0.01).

The equivalent stress in the acetabulum of patients with DDH decreased after RAO. Correction of the CE angle, AHI and ARA was considered to be important in reducing the mechanical stress in the hip joint.

Cite this article: Bone Joint J 2015;97-B:492–7.

Prophylactic intra-arterial administration of fasudil hydrochloride for vasospasm following subarachnoid haemorrhage

PURPOSE

We evaluated patients treated with prophylactic intra-arterial administration of fasudil hydrochloride (IAF) after subarachnoid haemorrhage (SAH).

MATERIALS AND METHODS

Between August 1998 and December 2012, 92 patients with aneurysmal SAH were treated with IAF for angiographic vasospasm without ischemic symptoms after their follow-up angiography. Patients comprised 50 women and 42 men, aged 24-83 (mean 56.6) years. IAF consisted of 15 mg of fasudil hydrochloride dissolved in 20 ml physiological saline and injected through a catheter during approximately 15 min, after diagnostic angiography. The clinical outcome was evaluated using the Glasgow Outcome Scale (GOS) at discharge and ischemic lesions resulting from vasospasm were assessed on computed tomography (CT) scan at discharge.

RESULTS

Forty-eight patients underwent surgical clipping and 44 patients underwent endovascular coiling. Angiographic improvement was observed in all patients (100 %). At discharge, 76 (83.0 %) of 92 patients showed good recovery on GOS. Nine patients developed progression of delayed ischemic neurological deficits (DIND) and three of these patients had ischemic lesions on CT scans. No patient had any significant changes in vital signs or any other adverse effects resulting from IAF.

CONCLUSION

IAF therapy was safe and effective for patients with vasospasm following SAH. Prophylactic IAF therapy may prevent symptomatic vasospasm.