Evidence for a finite-momentum Cooper pair in tricolor d-wave superconducting superlattices

Fermionic superfluidity with a nontrivial Cooper-pairing, beyond the conventional Bardeen-Cooper-Schrieffer state, is a captivating field of study in quantum many-body systems. In particular, the search for superconducting states with finite-momentum pairs has long been a challenge, but establishing its existence has long suffered from the lack of an appropriate probe to reveal its momentum. Recently, it has been proposed that the nonreciprocal electron transport is the most powerful probe for the finite-momentum pairs, because it directly couples to the supercurrents. Here we reveal such a pairing state by the non-reciprocal transport on tricolor superlattices with strong spin-orbit coupling combined with broken inversion-symmetry consisting of atomically thin d-wave superconductor CeCoIn5. We find that while the second-harmonic resistance exhibits a distinct dip anomaly at the low-temperature (T)/high-magnetic field (H) corner in the HT-plane for H applied to the antinodal direction of the d-wave gap, such an anomaly is absent for H along the nodal direction. By carefully isolating extrinsic effects due to vortex dynamics, we reveal the presence of a non-reciprocal response originating from intrinsic superconducting properties characterized by finite-momentum pairs. We attribute the high-field state to the helical superconducting state, wherein the phase of the order parameter is spontaneously spatially modulated.

Unconventional superconductivity in UTe2

The novel spin-triplet superconductor candidate UTe₂was discovered only recently at the end of 2018 and already attracted enormous attention. We review key experimental and theoretical progress which has been achieved in different laboratories. UTe₂is a heavy-fermion paramagnet, but following the discovery of superconductivity, it has been expected to be close to a ferromagnetic instability, showing many similarities to the U-based ferromagnetic superconductors, URhGe and UCoGe. This view might be too simplistic. The competition between different types of magnetic interactions and the duality between the local and itinerant character of the 5fUranium electrons, as well as the shift of the U valence appear as key parameters in the rich phase diagrams discovered recently under extreme conditions like low temperature, high magnetic field, and pressure. We discuss macroscopic and microscopic experiments at low temperature to clarify the normal phase properties at ambient pressure for field applied along the three axis of this orthorhombic structure. Special attention will be given to the occurrence of a metamagnetic transition atH_m= 35 T for a magnetic field applied along the hard magnetic axisb. Adding external pressure leads to strong changes in the magnetic and electronic properties with a direct feedback on superconductivity. Attention is paid on the possible evolution of the Fermi surface as a function of magnetic field and pressure. Superconductivity in UTe₂is extremely rich, exhibiting various unconventional behaviors which will be highlighted. It shows an exceptionally huge superconducting upper critical field with a re-entrant behavior under magnetic field and the occurrence of multiple superconducting phases in the temperature-field-pressure phase diagrams. There is evidence for spin-triplet pairing. Experimental indications exist for chiral superconductivity and spontaneous time reversal symmetry breaking in the superconducting state. Different theoretical approaches will be described. Notably we discuss that UTe₂is a possible example for the realization of a fascinating topological superconductor. Exploring superconductivity in UTe₂reemphasizes that U-based heavy fermion compounds give unique examples to study and understand the strong interplay between the normal and superconducting properties in strongly correlated electron systems.

Ultrastructural Features of the Aortic Wall in a Patient with Kommerell Diverticulum

We report on the ultrastructural features of the aortic wall in a patient with Kommerell diverticulum. A 70-year-old woman with a right aortic arch, aberrant left subclavian artery, and Kommerell diverticulum underwent a successful total arch replacement plus the frozen elephant trunk procedure with anatomical left subclavian artery reconstruction. Small pieces of the ascending aorta, distal arch, right common carotid artery, and left subclavian artery were investigated ultrastructurally. In the ascending aortic wall, multiple cystic cavities were observed in the subintimal region of the media by scanning electron microscopy. Changes in organelles, including mild dilation of rough-surfaced endoplasmic reticulum and mitochondrial swelling and degrading, were also observed in all specimens by transmission electron microscopy. These ultrastructural features may indicate the fragility or stress of the aortic wall and are useful when considering the early surgical intervention of a patient with Kommerell diverticulum.

[Surgical Strategy for Aortic Arch Aneurysm Depending on the Patient's Condition:Proper Selection of Open Surgery or Thoracic Endovascular Repair]

OBJECTIVES

We investigated the validity of the surgical strategy for aortic arch aneurysm depending on the patient's condition.

METHODS

Between 2014 and 2019, 70 patients underwent total arch replacement (TAR) and 14 patients underwent fenestrated thoracic endovascular aortic repair( fTEVAR) for aortic arch aneurysm. We selected the surgical strategy on the basis of the patient's condition with or without frailty and if surgical risks including cancer or a respiratory condition precluded open surgery.

RESULTS

The preoperative average ages were 73.3±7.8 years in the TAR group and 73.9±6.1 years in the fTEVAR group (p=0.93). EuroSCORE Ⅱ was 4.3±3.6 in the TAR group and 6.0±3.3 in the fTEVAR group (p=0.03). Frailty was observed in 11 patients (15.7%) in the TAR group and fivepatients (35.7%) in the fTEVAR group (p=0.08). In the fTEVAR group, there were three patients (21.4%) with cancer and three patients (21.4%) with a respiratory condition that precluded open surgery. The overall 30-day mortality rate was 0% for both groups, and the in-hospital mortality rate was 2.9% in the TAR group and 0% in the fTEVAR group (p=0.52). The incidence of stroke was 2.9% (two patients) in the TAR group and 7.1%( one patient) in the fTEVAR group( p=0.43). However, all stroke patients were able to walk at discharge. The cumulative survival rate was 88.9% and 83.5% in the TAR group and 85.1% and 68.1% in the fTEVAR group at two and five years, respectively (p=0.173). There were both 98.1% of patients in the TAR group and 85.7% and 75.0% of patients in the fTEVAR group who were free from reoperations at two and five years, respectively( p<0.01).

CONCLUSIONS

Our surgical strategy and outcomes for aortic arch aneurysm were generally appropriate. It is important to select open surgery or TEVAR depending on the patient's condition.

Emergency Endovascular Aneurysm Repair Coupled with Staged Omentopexy for Primary Aorto-Duodenal Fistula

A primary aorto-duodenal fistula (ADF), a rare, spontaneous development of a communication between the aorta and duodenum, is a disastrous complication of an abdominal aortic aneurysm. A 73-year-old patient with primary ADF underwent emergent endovascular aneurysm repair (EVAR), followed by staged omentopexy, without removing a stent graft (SG). The patient received long-term treatment with antibiotics, and there has been no evidence of infection during a follow-up period of three years. Emergency EVAR coupled with omentopexy, may be a treatment option for primary ADF, even when it means leaving the SG in a potentially infectious site.

Detection of Hole Pockets in the Candidate Type-II Weyl Semimetal MoTe_{2} from Shubnikov-de Haas Quantum Oscillations

The bulk electronic structure of T_{d}-MoTe_{2} features large hole Fermi pockets at the Brillouin zone center (Γ) and two electron Fermi surfaces along the Γ-X direction. However, the large hole pockets, whose existence has important implications for the Weyl physics of T_{d}-MoTe_{2}, has never been conclusively detected in quantum oscillations. This raises doubt about the realizability of Majorana states in T_{d}-MoTe_{2}, because these exotic states rely on the existence of Weyl points, which originated from the same band structure predicted by density functional theory (DFT). Here, we report an unambiguous detection of these elusive hole pockets via Shubnikov-de Haas (SdH) quantum oscillations. At ambient pressure, the quantum oscillation frequencies for these pockets are 988 and 1513 T, when the magnetic field is applied along the c axis. The quasiparticle effective masses m^{*} associated with these frequencies are 1.50 and 2.77 m_{e}, respectively, indicating the importance of Coulomb interactions in this system. We further measure the SdH oscillations under pressure. At 13 kbar, we detected a peak at 1798 T with m^{*}=2.86m_{e}. Relative to the oscillation data at a lower pressure, the amplitude of this peak experienced an enhancement, which can be attributed to the reduced curvature of the hole pockets under pressure. Combining our experimental data with DFT+U calculations, where U is the Hubbard parameter, our results shed light on why these important hole pockets have not been detected until now.

Endovascular Aortic Aneurysm Repair without Type 2 Endoleak Using Concomitant N-Butyl-2-Cyanoacrylate Injection into the Abdominal Aortic Aneurysm Sac

BACKGROUND

The aim of this study was to evaluate our new method to occlude target lumber arteries using N-butyl-2-cyanoacrylate (NBCA) during endovascular aneurysm repair (EVAR) for prevention of type 2 endoleak (T2E).

METHODS AND RESULTS

Between 2013 and 2018, 176 patients who underwent EVAR for abdominal aortic aneurysm (AAA) were reviewed. Starting from October 2015, 83 patients (treatment group) underwent NBCA injection into the aneurysmal sac during EVAR. The incidence of T2E at 7 days and AAA sac diameter 12 months after EVAR were compared with those of the control group comprising 93 consecutive patients who underwent EVAR alone before 2015. The incidence of T2E at 7 days was significantly lower in the treatment group (2.4%) than in the control group (22.6%) (P < 0.001). AAA sac diameter at 12 months in the treatment group had a mean decrease of 6.6 mm as compared with the mean 4.4 mm in the control group (P = 0.026). In multivariate analysis, NBCA injection was significantly related to the reduction of incidence of T2E at 7 days (odds ratio = 11.8, P < 0.001) and a decrease in AAA sac diameter at 12 months (P < 0.001). There was no NBCA injection-related complication and reintervention in the treatment group.

CONCLUSIONS

NBCA injection might be safe and useful to reduce the incidence of T2Es and to prevent AAA sac expansion.

Observation of a Magnetopiezoelectric Effect in the Antiferromagnetic Metal EuMnBi_{2}

We have experimentally studied a magnetopiezoelectric effect predicted recently for magnetic metals with low crystal symmetries. In EuMnBi_{2} with antiferromagnetic Mn moments at 77 K, dynamic displacements emerge along the a direction upon application of ac electric fields in the c direction and increase in proportion to the applied electric fields. Such displacements are not observed along the c direction of EuMnBi_{2} or EuZnBi_{2} with nonmagnetic Zn ions. As temperature increases from 77 K, the displacement signals decrease and disappear at about 200 K, above which electric conduction changes from coherent to incoherent. These results demonstrate the emergence of the magnetopiezoelectric effect in a magnetic metal lacking inversion and time-reversal symmetries.

Surgical resection of the giant right coronary artery aneurysm

A 74-year-old man had undergone two-vessel coronary artery bypass grafting (CABG), 19 years ago, with the left internal mammary artery (LITA) to the left anterior descending artery and the saphenous vein graft (SVG) to the posterior descending artery. In outpatient care, a thoracic aortic aneurysm was suspected by the chest X-ray. In the computed tomography, appeared the distal arch aortic aneurysm, abdominal aortic aneurysm (AAA), and giant right coronary artery aneurysm (rCAA). The diameter of rCAA was 70 mm and it oppressed the right atrium and ventricle of the heart. The patient was referred to our hospital. After the initial treatment of distal arch aneurysm and AAA, surgical treatment for the rCAA was performed. The rCAA was resected completely and CABG with new SVG was performed without cardiopulmonary bypass. The histopathology of rCAA wall revealed that the etiology was an atherosclerotic change. The postoperative course was good, the oppressed right heart system was released and the hemodynamics of the tricuspid valve showed improvement.

Infected Abdominal Aortic Aneurysm Caused by Campylobacter Jejuni

A 69-year-old man presented with abdominal pain. Enhanced computed tomography (ECT) showed abdominal aortic aneurysm (AAA) with vessel wall thickening. Follow-up ECT on day 3 of admission showed expansion of the AAA. Endovascular abdominal aortic repair (EVAR) was urgently performed. Since preoperative blood cultures revealed Campylobacter jejuni infection, the antibiotics imipenem/cilastatin were administered for five weeks, followed orally by Clarithromycin. The patient was discharged on postoperative day 45. There was no recurrence of the aneurysm at 9 months after EVAR. To the best of our knowledge, this is the first report of EVAR for infected AAA caused by Campylobacter jejuni.

Stanford Type A Acute Aortic Dissection with Intimal Intussusception

In case of complete circumferential dissection of the ascending aorta, the dissected flap has the potential to fold backwards, causing several complications. We report two cases of Stanford type A acute aortic dissection (AAD) whose intimal flaps intussuscepted into the left ventricular outflow tract.Case 1: A 41-year-old man with AAD in whom transthoracic echocardiography (TTE) showed the dissected flap as folded back into the left ventricular outflow tract, causing severe aortic regurgitation (AR) with rapidly progressing acute pulmonary edema. Despite performing salvage surgery, the patient could not be rescued.Case 2: An 81-year-old man with annuloaortic ectasia developed Stanford type A AAD. TTE showed an extremely mobile intimal flap intussuscepting into the left ventricular outflow tract. However, AR was not severe as it was prevented by the flap itself. The patient was rescued by performance of the modified Bentall procedure.

Quasilinear quantum magnetoresistance in pressure-induced nonsymmorphic superconductor chromium arsenide

In conventional metals, modification of electron trajectories under magnetic field gives rise to a magnetoresistance that varies quadratically at low field, followed by a saturation at high field for closed orbits on the Fermi surface. Deviations from the conventional behaviour, for example, the observation of a linear magnetoresistance, or a non-saturating magnetoresistance, have been attributed to exotic electron scattering mechanisms. Recently, linear magnetoresistance has been observed in many Dirac materials, in which the electron–electron correlation is relatively weak. The strongly correlated helimagnet CrAs undergoes a quantum phase transition to a nonmagnetic superconductor under pressure. Here we observe, near the magnetic instability, a large and non-saturating quasilinear magnetoresistance from the upper critical field to 14 T at low temperatures. We show that the quasilinear magnetoresistance may arise from an intricate interplay between a nontrivial band crossing protected by nonsymmorphic crystal symmetry and strong magnetic fluctuations.

The electronic structure of the helimagnet CrAs is unusual due to its nonsymmorphic crystal symmetry. Here, the authors observe quasilinear magnetoresistance close to a pressure-driven superconducting transition, which may arise from the interaction of the band structure and magnetic fluctuations.

Internal iliac artery aneurysmo-colonic fistula after endovascular stent-graft repair: a case report

We describe rare ilio-enteric fistula that developed after endovascular repair of a left internal iliac artery aneurysm (IIAA). An 83-year-old man with a history of previous surgeries via laparotomies suddenly developed a high fever 3 years after undergoing endovascular abdominal aortic repair (EVAR) with a stent-graft to treat a left isolated IIAA. Computed tomography imaging revealed a fistula between the IIAA and the sigmoid colon. A colostomy was created because severe intraperitoneal adhesions prevented resection of the IIAA. The postoperative course was uneventful and the patient remained free of infection without antibiotics. Residual aneurysms can cause complications after EVAR.

Stress echocardiographic assessment of mitral valve function repaired using rough-zone trimming

Background

We invented novel mitral valve repair technique; rough-zone trimming procedure (RZT) for anterior mitral valve prolapse. Prolapse site was resected in obtuse triangle shape and sutured edges to creates deep coaptation and improves regurgitation. Though it is simple and reproducible technique, functional mitral stenosis is a risk. Valve function and hemodynamics were investigated using dobutamine stress echocardiography (DSE) in patients after mitral valve repair using RZT.

Methods

Patients underwent RZT for the anterior mitral valve (AML, n = 10), quadrangular resection (QR) of the posterior mitral valve (PML; n = 4), RZT + QR of bileaflet valves (bileaflet; n = 4) and healthy individuals (control; n = 10) and were assessed by DSE (doses up to 20 μg/Kg/min). Echocardiographic data including mitral valve area (MVA), mitral valve mean pressure gradient (MVmeanPG), and systolic pulmonary artery pressure (sPAP) were measured at rest and at peak stress.

Results

Rest/stress MVA (cm²), MVmeanPG (mmHg) and sPAP (mmHg) were 2.8 ± 0.4 and 3.4 ± 0.3, 3.3 ± 1.1 and 7.4 ± 4.1, and 25.7 ± 4.7and 49.1 ± 4.1, respectively, in the AML group. Dobutamine stress increased all parameters but not to pathological levels. The results were similar to those of the other groups after mitral valve repair, whereas MVA was larger and MVmeanPG was lower in the control than in the AML group.

Conclusions

Valve repair using RZT does not pathologically obstruct the mitral valve, either at baseline or during dobutamine stress, and does not affect valve hemodynamics and reserve.

[Intraoperative evaluation for residual mitral valve regurgitation; usefulness of the retrograde cardioprotective beating test]

Intraoperative evaluation is important for successful mitral valve plasty (MVP). We performed a saline injection test and a retrograde cardioprotective beating test (RC-beating test) for intraoperative evaluation. The concept of the RC- beating test is evaluation of residual mitral valve regurgitation( MR) under cardiac beating. A 66-year-old man with severe MR underwent MVP. The P3 chorda was ruptured and we performed quadrangular resection. The saline injection test showed trivial regurgitation. We then performed the RC-beating test and it revealed severe leakage from the posterior commissure(PC). Since the PC had a sclerotic change, another quadrangular resection was performed. Moreover,as the anterior leaflet( A3) was slightly elongated, the region was resected in an obtuse-angled triangle shape and repaired by suturing the edges. The final RC-beating test showed no residual leakage. The RC-beating test is useful for detecting residual mitral valve leakage.

Controllable Rashba spin-orbit interaction in artificially engineered superlattices involving the heavy-fermion superconductor CeCoIn5

By using a molecular beam epitaxy technique, we fabricate a new type of superconducting superlattices with controlled atomic layer thicknesses of alternating blocks between the heavy-fermion superconductor CeCoIn5, which exhibits a strong Pauli pair-breaking effect, and nonmagnetic metal YbCoIn5. The introduction of the thickness modulation of YbCoIn5 block layers breaks the inversion symmetry centered at the superconducting block of CeCoIn5. This configuration leads to dramatic changes in the temperature and angular dependence of the upper critical field, which can be understood by considering the effect of the Rashba spin-orbit interaction arising from the inversion symmetry breaking and the associated weakening of the Pauli pair-breaking effect. Since the degree of thickness modulation is a design feature of this type of superlattices, the Rashba interaction and the nature of pair breaking are largely tunable in these modulated superlattices with strong spin-orbit coupling.

[Revascularization surgery for isolated unilateral absence of the right pulmonary artery]

We describe a baby girl with isolate absence of the right pulmonary artery. She had tachypnea just after birth. Several examinations showed absence of the right pulmonary artery and an aortopulmonary collateral artery. After follow-up, cardiac catheterization was performed the age of 14 months. It showed mild pulmonary artery hypertension. The posterior wall of right pulmonary artery was reconstructed with U-shaped in situ pulmonary artery flap and the anterior wall was reconstructed with autologous pericardium patch. Enhanced computed tomography was performed on postoperative day 9 showed occlusion of the right pulmonary artery by a thrombus. Emergency catheterization and thrombolytic therapy was performed with no success. Then, we successfully performed thrombectomy by open surgery. Cardiac catheterization performed at 6 months after the operation showed patency of the right pulmonary artery and improvement of pulmonary artery hypertension.

Infradiaphragmatic malperfusion of acute aortic dissection associated with previous abdominal aortic aneurysm repair

PURPOSE

To evaluate the association of previous abdominal aortic aneurysm (AAA) graft replacement with infradiaphragmatic malperfusion in patients with acute aortic dissection.

METHODS

Between November 2006 and June 2011, 133 patients were referred to our hospital for management of acute aortic dissection. Eight (6.0 %) of these patients had undergone AAA graft replacement prior to the acute aortic dissection. We compared the computed tomography (CT) images of these 8 patients with those of the remaining 125 patients without previous AAA graft replacement, in terms of organ ischemia as a complication induced by acute aortic dissection.

RESULTS

Infradiaphragmatic malperfusion from acute aortic dissection was confirmed in four of the eight patients who had undergone AAA graft replacement. Contrasted CT scan images indicated that the main cause of infradiaphragmatic malperfusion was collapse of the true lumen from compression by the false lumen into the suprarenal aorta. Although there was no significant difference between the groups in terms of cerebral ischemia and myocardial ischemia, bilateral leg ischemia and visceral ischemia occurred more frequently in the patients who had undergone AAA graft replacement.

CONCLUSION

Previous AAA graft replacement is a risk factor for infradiaphragmatic malperfusion in patients with acute aortic dissection.

Anomalous upper critical field in CeCoIn5/YbCoIn5 superlattices with a Rashba-type heavy Fermion interface

We report a highly unusual angular variation of the upper critical field (H(c2)) in epitaxial superlattices CeCoIn(5)(n)/YbCoIn(5)(5), formed by alternating layers of n and a 5 unit-cell thick heavy-fermion superconductor CeCoIn(5) with a strong Pauli effect and normal metal YbCoIn(5), respectively. For the n=3 superlattice, H(c2)(θ) changes smoothly as a function of the field angle θ. However, close to the superconducting transition temperature, H(c2)(θ) exhibits a cusp near the parallel field (θ=0°). This cusp behavior disappears for n=4 and 5 superlattices. This sudden disappearance suggests the relative dominance of the orbital depairing effect in the n=3 superlattice, which may be due to the suppression of the Pauli effect in a system with local inversion symmetry breaking. Taking into account the temperature dependence of H(c2)(θ) as well, our results suggest that some exotic superconducting states, including a helical superconducting state, might be realized at high magnetic fields.

Surgical treatment for neonatal Ebstein's anomaly with circular shunting

We report a case of surgical treatment for neonatal Ebstein's anomaly with circular shunting. A prenatal diagnosis of Ebstein's anomaly was made at 30 weeks of gestation. In addition to severe tricuspid regurgitation, severe pulmonary regurgitation was also noted, resulting in a 'circular shunt'. At 38 weeks and 2 days of gestation, the baby was delivered by Caesarean section. A two-stage palliative operation was planned. As the first palliation, the pulmonary artery was ligated 1 h after birth to eliminate the circular shunt. Lipo-prostaglandin E(1) was administrated continuously to keep the ductus arteriosus patent. Four days after first operation, modified Starnes operation was performed as the second-stage palliation. The tricuspid valve was closed by an ePTFE patch with 3-mm fenestration. Pulmonary blood flow was supplied by a right modified Blalock-Taussig shunt with a 3.5-mm diameter ePTFE graft. The infant's postoperative haemodynamic status was stable. The patient is being followed up carefully and is scheduled to have a univentricular repair in the future.

[Surgical treatment of coronary aneurysm after percutaneous coronary intervention]

A 61-year-old man with acute myocardial infarction underwent percutaneous coronary intervention with stent for the left main coronary artery (LMT) and the left anterior descending artery (LAD). Three months later, we recognized the LMT aneurysm complicated with possible thrombus formation, which developed in size during 6 months. In addition, the LAD stent showed significant in-stent stenosis. For the purpose of supplying blood flow to the distal of LAD, and avoiding myocardial infarction due to distal thrombosis possibly originated from LMT aneurysm, we decided to perform surgical operation. On preoperative examination, this patient had an obstruction of the right internal carotid artery. Although the direct repair of LMT aneurysm requires conventional approach with cardiopulmonary bypass, we applied off-pump coronary artery bypass grafting( OPCAB) considering the risk of cerebrovascular event. Consequently, OPCAB was performed in usual fashion [right internal thoracic artery (RITA) -LAD, left internal thoracic artery-left circumflex artery (LITA-LCX)] followed by the ligation of the proximal of LAD and LCX without cardiopulmonary bypass. The patient had a good operative course.

Ischemic Colitis Following Transarterial Embolization for Type 2 Endoleak of EVAR: Report of a Case

A 71 year old man was diagnosed to have enlargement of abdominal aortic aneurysm due to type 2 endoleak two years after endovascular aneurysm repair (EVAR). 3D-CT demonstrated a type 2 endoleak that originated from the superior mesenteric artery that fed the inferior mesenteric artery and the right iliolumbar artery that flowed into the 4th lumbar artery. Transarterial embolization was performed by means of N-butyl-2-cyanoacrylate (NBCA). After the treatment, he suffered ischemic colitis that extended from the sigmoid colon to the descending colon. Conservative treatment was mainly performed, and clinical improvement was observed over time. He was discharged after 73 postoperative days.

Conversion to Open Repair from Emergency EVAR in a Patient with Ruptured AAA: Report of a Case

A 77-year-old woman with a ruptured abdominal aortic aneurysm (AAA) was transferred to our hospital. Due to a severe comorbidity, endovascular aortic repair of the ruptured AAA was proposed. During the operation, although a Zenith(®) AAA endovascular graft was deployed, digital subtracted angiography revealed an enhancement of the endoleak, and the patient became hemodynamically unstable. Therefore, we decided to convert to graft replacement of the abdominal aorta through a median laparotomy. During the postoperative period, the patient suffered from ischemic colitis, which resolved with conservative therapy. She was discharged after 33 postoperative days.

Cellulose sulfate suppresses immunoglobulin E production by murine B lymphocytes in vitro

BACKGROUND

Immunoglobulin (Ig) E plays an important role in the pathogenesis of allergic diseases such as atopic dermatitis and allergic asthma.We previously reported that a sulfate polysaccharide, fucoidan, suppressed IgE production by murine B cells in vitro. However, the mechanism by which fucoidan suppresses IgE production remains unclear.

OBJECTIVE

We incorporated sulfate groups into cellulose and studied their biological characteristics in vitro to explore the possibility of converting biologically neutral polysaccharides to active reagents with antiallergic functions.

MATERIAL AND METHODS

Cellulose was chemically processed using N,N-dimethylformamide (DMF) and DMF-sulfurtrioxide and recovered as cellulose sulfate with a molecular weight of around 10 kDa. We then studied the effect of cellulose sulfate on IgE production from B cells, IgE class-switching, and populations of IgE-secreting B cells prepared from murine spleen. We also investigated the effects of sulfated cellulose on the production of interleukin (IL) 4 and interferon (IFN) gamma and the expression of T-bet mRNA by splenic T cells. The cytotoxicity of cellulose sulfate was also examined.

RESULTS

Cellulose sulfate suppressed IgE production in B cells stimulated with IL-4 and anti-CD40 antibody by inhibiting IgE class-switch recombination and decreasing the number of IgE-secreting B cells in vitro. Moreover, both cellulose sulfate and fucoidan suppressed IL-4 production and enhanced IFN-gamma production by murine T cells stimulated with anti-CD3 and anti-CD28 antibodies, despite the decrease in T-bet mRNA expression.

CONCLUSIONS

Cellulose gains an antiallergic effect on B cells and T cells with the addition of sulfate groups.

Thoracic endovascular aortic repair and off-pump coronary artery bypass grafting after renal transplantation: a case report

Twelve years after receiving a renal transplant, a 50-year-old woman developed asthmatic symptoms. Chest CT revealed a descending thoracic aortic aneurysm. She had undergone percutaneous coronary intervention to treat the left anterior descending artery 10 years earlier. Coronary artery angiography revealed restenosis of the left anterior descending artery (99%, #6 in-stent). Because cardiopulmonary bypass may cause problems for transplanted kidney, we performed off-pump coronary artery bypass grafting (left internal thoracic artery to left anterior descending artery) and thoracic endovascular graft placement to treat the aortic aneurysm. Considering that the artery of the transplanted kidney was attached to the right iliac artery, and then the left common femoral artery was selected as the access root for GORE TAG(®) endografts (34 × 200 and 34 × 150 mm) (stentgrafts were deployed for the descending aortic artery). Postoperative angiography showed a patent bypass graft. Postoperative CT confirmed the absence of endoleaks. The postoperative course was uneventful, and she was discharged without complications. Ischemic heart disease and descending thoracic aortic aneurysm in recipients of kidney transplants can be treated using off-pump coronary bypass grafting and thoracic endovascular graft placement. The transplanted kidney was protected without using cardiopulmonary bypass (CPB).

Fetal cardiac dimensions at 14-40 weeks' gestation obtained using cardio-STIC-M

OBJECTIVES

To establish normative reference ranges of fetal cardiac dimensions derived from volume datasets acquired using spatiotemporal image correlation with M-mode display (cardio-STIC-M).

METHODS

A cross-sectional study was undertaken on singleton pregnancies with normal fetuses and accurate gestational ages. Cardio-STIC volume datasets were acquired by experienced operators using a high-resolution ultrasound machine; these were maneuvered to obtain a four chamber-view with exactly horizontal interventricular septum (IVS). Cardiac dimensions were measured in STIC-M-mode using 4D View software.

RESULTS

A total of 657 measurements, at a rate of between 15 and 37 per week, were obtained. Normal reference ranges for biventricular outer diameter, left and right ventricular inner diameter, left and right ventricular wall thickness, IVS thickness, left to right ventricular diameter ratio and left and right ventricular shortening fractions were constructed based on best-fit equations as a function of gestational age, fetal head circumference and biparietal diameter. Thirty-four volume datasets of abnormal fetal hearts were also separately assessed, many of which showed abnormal cardiac dimensions.

CONCLUSIONS

This is the first report on normal ranges of fetal cardiac dimensions constructed using the new cardio-STIC-M technology. Preliminary evaluation suggests that these reference ranges may be a useful tool in the assessment of fetal cardiac abnormalities.

True Atomic Resolution Imaging on Semiconductor Surfaces with Noncontact Atomic Force Microscopy

The constant vibration mode and the constant excitation mode in noncontact atomic force microscopy were compared to investigate the force interaction between tip and surface. As a result, we found that the constant excitation mode is much more gentle than the constant vibration mode. We also succeeded in atomic resolution imaging on InP(110) surface not only in the noncontact region but in the contact region for the first time. Furthermore, we found the discontinuity of the force gradient curve on reactive Si(111)7×7 reconstructed surface. We proposed a model to explain the discontinuity with the crossover between the physical and chemical bonding interaction.

Surgical treatment for aortic coarctation with chronic type B dissection: report of a case

The aim of this paper is to report a rare case of aortic coarctation with type B aortic dissection. A 37 year-old man had sudden, intense back pain. Enhanced computed tomography revealed aortic coarctation (CoA) at the proximal descending aorta and acute type B aortic dissection just distal to the CoA. The dissecting, descending aortic aneurysm had expanded to a maximal diameter of 52 mm. The aortic coarctation was resected and then the descending aorta was replaced with prosthetic grafts in an uneventful procedure. Surgical repair resulted in a good outcome.

[Extirpation of a thrombus during pulmonary metastasectomy in a patient with chronic pulmonary thromboembolism]

A 57-year-old woman with chronic pulmonary thromboembolism was diagnosed to have metastatic lung tumors 6 months after an operation performed for colon cancer. There were no respiratory symptoms associated with the pulmonary thromboembolism. Computed tomography showed 2 pulmonary masses in the right middle and lower lobes, and a thrombus in the inferior trunk of the right pulmonary artery. Excision of the 2 pulmonary metastases was performed and the thrombus in the pulmonary artery was also removed at the same time. Partial improvement of the pulmonary blood flow was observed in the postoperative pulmonary scintigram. Chronic pulmonary thromboembolism without respiratory symptoms is not usually an indication for extirpation of thrombus. However, incidental extirpation of a pulmonary thrombus at the time of other pulmonary surgery should be considered, as it may yield an improvement of the pulmonary blood flow.

[Off-pump coronary artery bypass surgery for the ischemic cardiomyopathy patient with moderate mitral regurgitation and stenosis of bilateral vertebral arteries]

We report a 71-year-old man who had severe coronary and cerebral vascular disease with moderate mitral regurgitation (MR). Left ventricular reconstruction and mitral valve surgery were considered for poor left ventricular function and dilatation with MR. However, low blood pressure during cardiac arrest was risk for stroke due to severe stenosis of bilateral vertebral arteries. The myocardial viability of the anterior wall and inferior wall was confirmed by thallium-201 rest-redistribution single photon emission computed tomography (SPECT). Therefore, off-pump coronary artery bypass grafting (OPCAB) was selected for the patient. Only three Lima sutures were used for keeping the optimal heart position. Coronary anastomoses were done in sequence right gastroepiploic artery (RGEA)-#4 posterior descending (PD), left internal thoracic artery (LITA)-#9-#14 (sequential), RITA-#8 left anterior descending (LAD). No neurological complication occurred postoperatively. Left ventricular function and MR gradually improved. Final ejection fraction (EF) is 51% and MR is trivial. This case demonstrated improvement of MR by only revascularization according to preoperative viability assessment.

[Infective endocarditis with acute embolism to the lower extremity artery caused by a vegetation: report of a case]

Successful surgical treatment of a case of infective endocarditis with embolism to a lower extremity artery is reported. A 71-year-old man was referred to our hospital for the treatment of infective endocarditis. Echocardiography showed a vegetation on the non-coronary cusp of the aortic valve measuring 19 mm in diameter. We planned surgical treatment, including aortic valve replacement, however, embolism of a lower extremity artery by the vegetation occurred during the waiting period for the operation. We removed the offending vegetation from the popliteal artery and replaced the peccant aortic valve with a prosthetic valve in separate operations. The postoperative course was uneventful and the patient was transferred to another hospital on the 33rd day after the valve replacement surgery.

Nephropathy of cyanotic congenital heart disease: clinical characteristics and effectiveness of an angiotensin-converting enzyme inhibitor

AIMS

Nephropathy has long been recognized as a potential complication of cyanotic congenital heart disease (CCHD). There have been few large-scale studies or clinical reports on renal impairment in patients with CCHD; similarly, very few studies have examined the drug treatment of nephropathy in CCHD. We examined the clinical characteristics and effectiveness of enalapril, an angiotensin-converting enzyme inhibitor (ACE-I), in patients with CCHD complicated with significant proteinuria.

MATERIALS AND METHODS

The clinical records of 37 patients with CCHD were evaluated; all were older than 10 years of age (median 19, range from 10 to 27) and had regular check-ups, including urinalysis. The treatment criteria for enalapril administration included significant proteinuria (urinary excretion > 1.0 g/24 h), stable cardiac condition and blood pressure within the normal range.

RESULTS

Eleven patients (29.7%) had persistent proteinuria, 6 patients met the enalapril treatment criteria and 5 patients were treated for more than 12 months. Enalapril apparently reduced the urinary protein excretion in 4 of the 5 patients (80%). No consistent improvement of renal function, as evidenced in the glomerular filtration rate (GFR), renal plasma flow (RPF) or filtration fraction (FF) was found in these patients, but neither were any significant adverse effects noted.

CONCLUSION

The incidence of nephropathy among patients with CCHD was about 30%, which was consistent with previous studies. It is worth considering the use of ACE-I when nephropathy accompanies CCHD.

Immunological detection of a novel advanced glycation end-product

BACKGROUND

The advanced stage of the Maillard reaction that leads to the formation of advanced glycation end-products (AGEs) plays an important role in the pathogenesis of angiopathy in diabetic patients and in the aging process. Recently, it has been proposed that the intermediates contributing to AGE formation include dicarbonyl intermediates such as glyoxal, methylglyoxal, and 3-deoxyglucosone (3-DG). In the present study, we developed a novel, non-carboxymethyllysine (CML) anti-AGE antibody that recognizes serum proteins and peptides modified by 3-DG in vivo.

MATERIALS AND METHODS

AGE-modified serum albumins were prepared by incubation of rabbit serum albumin with 3-DG or D-glucose. After immunization of rabbits, anti-AGE antisera were subjected to affinity chromatography on a Sepharose 4B column coupled with CML-BSA, or AGE-BSA created by incubation with 3-DG (AGE-6) or D-glucose (AGE-1). The AGE-Ab-6 and AGE-Ab-1 thus obtained was used to investigate AGEs in serum from diabetic patients on hemodialysis.

RESULTS

Characterization of the novel AGE-Ab-6 obtained by immunoaffinity chromatography was performed with a competitive ELISA and immunoblot analysis. This antibody specifically cross-reacted with proteins modified by 3-DG. AGE-6 was detected in diabetic serum as three peaks with apparent molecular weights of 200, 1.15, and 0.85 kD, while AGE-1 was detected as four peaks with apparent molecular weights of 200, 65, 1.15, and 0.85 kD.

CONCLUSION

This study provides new data on the pathways of AGE formation from 3-DG and methods for the immunochemical detection of AGEs. We also provide immunochemical evidence for the existence of six distinct AGEs in vivo among the AGE-modified proteins and peptides in the serum of diabetic patients on hemodialysis.

Neostriatal stimulation activates tongue-protruder muscle, but not tongue-retractor or facial muscles: an electrical and chemical microstimulation study in rats

Whether electrical microstimulation of a rat's striatal jaw region (SJR) in fact induced tongue or facial muscle activity in addition to jaw muscle activity was tested. Microstimulation of SJR-evoked EMG activity in a jaw-opener (anterior digastricus) and tongue-protruder (genioglossus). No activity was evoked in jaw-closers (temporalis or masseter), tongue-retractor (hyoglossus) or in facial muscles. In addition, the EMG effect could still be induced after extensive ablation of the neocortex; it was reproduced by microinjection of 50 mM kainic acid into SJR. The effective sites were histologically localized to a small central striatal region adjoining the anterior commissure. These findings may be of considerable value in understanding the striatal mechanism of orolingual dyskinesia involving involuntary jaw and tongue movements.

Analysis of mother-to-infant transmission of hepatitis C virus: quasispecies nature and buoyant densities of maternal virus populations

Mother-to-infant transmission of hepatitis C virus (HCV) was analyzed by sequencing of viral RNA and semiquantitative polymerase chain reaction following ultracentrifugation of maternal sera. In two mother-infant pairs, the hypervariable region 1 (HVR1) and carboxyl terminus of envelope 1 (E1) were sequenced. Both viral sequences in the infants were less diverse than those of their mothers. Although the E1 sequences were almost identical in each mother-infant pair, the HVR1 sequences of the infants were related, but not identical, to those of the mothers. Serial examinations of one infant revealed that the HVR1 nucleotide sequence did not change from 10 days to 3 months of age. In six mothers with uninfected infants, all of the dense fractions of sera contained significant amounts of HCV RNA, whereas in six mothers with infected infants, only two of those fractions contained significant amounts of HCV RNA. These results indicate that the strains of HCV detected in the infants were not dominant in the mothers, but were still transmissible to the infants. As dense fractions are known to contain antibody-bound HCV particles, maternal antibodies against HCV may inhibit viral transmission.

[Analysis of nuclear DNA heterogeneity of the hepatocellular carcinoma (HCC)]

To evaluate the objective proliferative activity in HCC nuclear DNA contents were measured by means of microspectrophotometry and at the same time the immunohistochemical technique using anti-PCNA antibody was employed. Surgically resected 26 HCCs were analyzed in terms of cell proliferative activity and regional heterogeneity. The analysis was performed by immunohistochemical demonstration of PCNA and pathologic histochemical study in formalin-fixed, paraffin-embedded specimens and cytophotometric measurements of nuclear DNA contents in fresh specimens. The results were as follows. 1) Nine HCCs showed regional ploidy heterogeneity. 2) PCNA labeling index and histological grade of the marginal area was much higher than that of the central area. From these results, we concluded that in the process of the HCC progression proliferative activity was decreased in the central area and was not decreased in the marginal area.