Breaking the trade-off between fast control and long lifetime of a superconducting qubit

The rapid development in designs and fabrication techniques of superconducting qubits has made coherence times of qubits longer. In the future, however, the radiative decay of a qubit into its control line will be a fundamental limitation, imposing a trade-off between fast control and long lifetime of the qubit. Here, we break this trade-off by strongly coupling another superconducting qubit along the control line. This second qubit, which we call “Josephson quantum filter” (JQF), prevents the first qubit from emitting microwave photons and thus suppresses its relaxation, while transmitting large-amplitude control microwave pulses due to the saturation of the quantum filter, enabling fast qubit control. This device functions as an automatic decoupler between a qubit and its control line and could help in the realization of a large-scale superconducting quantum processor by reducing the heating of the qubit environment and the crosstalk between qubits.

The trade-off between long lifetime and inevitable radiative decay to a control line has become a key limitation for superconducting qubits. Here, the authors break the trade-off by coupling another qubit to the control line of the first one to suppress its relaxation, while enabling fast qubit control.

P1354 Prognostic value of the left ventricular longitudinal and circumferential function in patients with takotsubo syndrome during the acute phase

Background

Takotsubo syndrome is generally considered a benign disease with a reversible condition; however, hemodynamic and electrical instability during the acute phase exposes patients to the risk of serious adverse in-hospital events. The purpose of this study was to investigate the prognostic value of the left ventricular longitudinal and circumferential function in patients with TTS during the acute phase.

Methods

We divided the 27 patients with TTS (77.4 ± 10.2 years old, 21 females) into two groups; the severe group (SG) of 9 patients (in-hospital death, mechanical assist devices such as IABP or ECMO, oozing rupture) and non-severe group (NSG) of 18 patients. The echocardiographic examination on admission, catheter hemodynamic assessment, and laboratory data, and ST-T change in electrocardiogram were compared between two groups.

Results

There were no differences in age, laboratory data, electrocardiogram findings between the two groups. The LVEF was lower in SG (35.3 ± 6.1% vs. 45.9 ± 13.5%, p = 0.03). The index of Ballooning, the ratio of the systolic left ventricular diameter of ballooning segments to that of basal segments, was higher in SG (2.07 ± 0.61% vs.1.60 ± 0.32%, p = 0.016). The circumferential fractional shortening (CFS) of ballooning segments was lower in SG (4.6 ± 3.2% vs. 18.2 ± 8.2%, p = 0.00007), CFS of basal segments was not different between the two groups, and the ratio of CFS of ballooning segments to CFS of basal segments (CFS imbalance index) was lower in SG (5.60 ± 3.84 vs. 10.83 ± 3.92, p = 0.00003). The left ventricular longitudinal fractional shortening was lower in SG (0.12 ± 0.09 vs. 0.46 ± 0.19, p = 0.00003). The absolute value of GLS was lower in SG (7.6 ± 4.3% vs. 13.0 ± 3.6%, p = 0.002). In all three cases of in-hospital death, the CFS imbalance index was lower than 0.14.

Conclusion

In patients with TTS, left ventricular longitudinal and circumferential function could be related to serious adverse in-hospital events.

Inversion of Qubit Energy Levels in Qubit-Oscillator Circuits in the Deep-Strong-Coupling Regime

We report on experimentally measured light shifts of superconducting flux qubits deep-strongly coupled to LC oscillators, where the coupling constants are comparable to the qubit and oscillator resonance frequencies. By using two-tone spectroscopy, the energies of the six lowest levels of each circuit are determined. We find huge Lamb shifts that exceed 90% of the bare qubit frequencies and inversions of the qubits' ground and excited states when there are a finite number of photons in the oscillator. Our experimental results agree with theoretical predictions based on the quantum Rabi model.

Effective Treatment With Daclatasvir and Asunaprevir in Kidney Transplant Patients Infected With Hepatitis C Virus: A Report of Two Cases

BACKGROUND

Hepatitis C virus (HCV) infection is known to affect long-term patient and graft survivals after kidney transplantation (KT). Recently, combination therapy with the use of 2 oral direct-acting antivirals, daclatasvir (DCV) and asunaprevir (ASV) reportedly showed a high rate of HCV eradication. We report the safety and efficacy of DCV and ASV therapy in 2 KT patients.

METHODS

The safety and viral responses were investigated in a prospective study of KT patients infected with HCV genotype 1. Two patients received 60 mg DCV once daily plus 100 mg ASV twice daily for 24 weeks.

RESULTS

A 69-year-old woman and a 57-year-old man underwent DCV and ASV therapy for 24 weeks. In both cases, the HCV genotype was 1b. Case 1 had undergone KT twice and had received treatment with pegylated interferon and ribavirin. She received DCV and ASV therapy 12 years after the 2nd KT, and had undetectable virus after only 6 weeks of treatment and at 24 weeks after the end of treatment (SVR24). The post-transplantation immunosuppressive therapy at that time comprised tacrolimus, mycophenolate mofetil, and prednisolone. The other case, after failure of interferon treatment, received DCV and ASV therapy 27 years after his KT and achieved SVR24. His immunosuppressive regimen at that time was mizoribine and prednisolone. DCV and ASV therapy did not affect renal graft function or tacrolimus blood concentrations.

CONCLUSIONS

DCV and ASV therapy had high antiviral effect and a low rate of adverse events in KT patients.

Nonclassical Photon Number Distribution in a Superconducting Cavity under a Squeezed Drive

A superconducting qubit in the strong dispersive regime of circuit quantum electrodynamics is a powerful probe for microwave photons in a cavity mode. In this regime, a qubit excitation spectrum is split into multiple peaks, with each peak corresponding to an individual photon number in the cavity (discrete ac Stark shift). Here, we measure the qubit spectrum in a cavity that is driven continuously with a squeezed vacuum generated by a Josephson parametric amplifier. By fitting the obtained spectrum with a model which takes into account the finite qubit excitation power, we determine the photon number distribution, which reveals an even-odd photon number oscillation and quantitatively fulfills Klyshko's criterion for nonclassicality.

Living Donor Kidney Transplantation After Brachytherapy for Prostate Cancer: Case Report

INTRODUCTION

There is no obvious criterion about kidney transplantation for patients with pretransplant malignancy. Minimum tumor-free waiting periods differ according to type of cancer, staging, site of occurrence, response to therapy, and risk of cancer recurrence. We report a case of living donor kidney transplantation (LDKT) in a patient after brachytherapy for prostate cancer.

CASE REPORT

The patient was a 65-year-old man with chronic kidney disease due to chronic glomerular nephritis. He received hemodialysis 3 times a week. His prostate-specific antigen level (PSA) was high (6.57 ng/mL), and he was diagnosed with prostate cancer (T1cN0M0, Gleason Score 3 + 4 = 7, 3/10) by needle biopsy in urology. He was treated with maximum androgen blockade (MAB) therapy and brachytherapy in May 2014. He underwent LDKT from a spousal donor at our department in December 2015, because urologists concluded that the prostate cancer was completely cured. Immunosuppression consisted of induction with basiliximab and maintenance with tacrolimus, mizoribine, and steroids. The postoperative course was uneventful. He discharged at postoperative day 29 with a serum creatinine level of 1.30 mg/dL. Three months after LDKT, his PSA level was 0.477 ng/mL, and there was no evidence of prostate cancer recurrence.

CONCLUSION

This is the first case of LDKT for patients with prostate cancer after brachytherapy in combination with MAB. There is no recurrence of prostate cancer so far; however, careful follow-up including PSA is necessary and important.

Living-donor kidney transplantation with existing anti-donor specific antibodies at a Japanese single center

Improving the short-term outcome of kidney transplantation, the rejection induced by anti-donor specific antibody (DSA) has been the large complication. We analyzed 324 living-donor kidney transplant recipients (procedures performed between April 2003 and August 2014) to investigate the outcome of kidney transplant recipients with DSA. We divided them into four groups (anti-blood type antibody alone, group A [n = 73]; anti-human lymphocyte antigen [HLA] antibody alone, group B [n = 11]; both antibodies, group C [n = 8]; and no DSA, group D [n = 232]) and investigated the incidence of rejection and those histologic findings. Each case with DSA underwent some desensitization therapy before transplantation. There was no significant difference in graft survival (all cases: 100% at 1 year, group A: 97.6%, B: 95.9%, C: 100%, and at 5 years, group D: 96.1%). There were some significant differences in incidence of acute antibody-mediated rejection (AAMR) and chronic active antibody-mediated rejection (CAAMR) among four groups (group A: 4.1% and 2.7%, B: 18.2% and 9.1%, C: 12.5% and 12.5%, D: 0% and 0.9%, respectively). Each AAMR case was improved by ordinary desensitization therapy, but half of the CAAMR cases, diagnosed early after transplantation, had no effect of any therapy to result in graft failure. Our results suggested that even the case with DSA could be transplanted safely by some desensitization therapy. However, we should be cautious regarding recipients with DSA for the long term even if there is no histologic change early after transplantation because graft loss may occur due to CAAMR.

Advantages and disadvantages of pre-emptive kidney transplantation: results from a single transplantation center

BACKGROUND

There is a growing tendency to perform pre-emptive kidney transplantation (PKT). However, less research has been performed on outcomes of PKT and kidney transplantation (KT) after long-term dialysis (LD).

METHODS

To elucidate advantages of PKT to KTLD, 96 patients who underwent living-donor KT at our university from 2000 to 2011 were enrolled for this study: 64 patients in the PKT0 (0 months dialysis) group; 14 patients in the PKT-3 group (less than 3 months dialysis); 18 patients in the LD (dialysis > 120 months) group. All recipients were assessed for patients' survival, graft survival, urinary tract infection, laboratory data, episodes of acute rejection, cytomegalovirus-related diseases, and other significant infectious diseases which required hospitalization.

RESULTS

Although there were no significant differences in 5-year graft survival (93.8% in PKT0, 85.7% in PKT-3, and 83.7% in control), 5-year patient survival is better in the PKT0 group (96.9%) and the PKT-3 group (92.9%) compared to 88.9% in the control group. Urinary tract infection is clearly correlated with the LD group (44.4% in the LD group vs 19.2% in the PKT group) primarily due to atrophic bladder and subsequent vesicoureteral reflux. Slightly higher rates of acute rejection were found in the PKT groups (30.8% vs 26.3%).

CONCLUSION

This study revealed that there are both advantages and disadvantages of PKT. It is clear, therefore, that PKT can be recommended for end-stage renal disease patients provided enough attention is paid to the onset of acute rejection.

Evaluation of renal allograft fibrosis by transient elastography (Fibro Scan)

BACKGROUND

Chronic allograft injury (CAI) is one of the most important factors for graft failure after renal transplantation. Protocol biopsy is the most valuable tool for revealing subclinical renal allograft failure. Transient elastography (TE) is a noninvasive technique that has shown utility for the assessment of hepatic and renal fibrosis. This study sought to evaluate whether TE was a viable and effective method for the assessment of renal allograft failure.

PATIENTS AND METHODS

Thirty-five patients underwent TE by Fibro Scan (Echosense, Paris, France). Biopsies were performed in 27 patients, allowing classification according to Banff chronic changes in the interstitium grade 0, grade 1 or grade 2.

RESULTS

Measurement of parenchymal stiffness was successful in 31 of 35 patients (91%). Stiffness was significantly correlated with interstitial fibrosis (P < .05) and inversely related with estimated glomerular filtration rate (eGFR; P < .05). Stiffness values of patients with eGFR > 50 mL/min were lower than those of patients with eGFR < 50 mL/min (P < .05). Patients classed as CAI Banff grade 0 had significantly less parenchymal stiffness than patients with Banff grade 1 or grade 2 CAI (P < .05). Parenchymal stiffness measured by TE reflected interstitial fibrosis in renal allograft.

CONCLUSION

Assessment of parenchymal renal allograft stiffness by TE was effective for identifying patients with CAI who may subsequently benefit from biopsy and modification of the immunosuppressive regimen. Assessment of parenchymal renal allograft stiffness can be effective for identifying patients with CAI. TE has the potential to reduce the number of renal allograft biopsies required for accurate assessment of CAI.

Microwave down-conversion with an impedance-matched Λ system in driven circuit QED

By driving a dispersively coupled qubit-resonator system, we realize an "impedance-matched" Λ system that has two identical radiative decay rates from the top level and interacts with a semi-infinite waveguide. It has been predicted that a photon input from the waveguide deterministically induces a Raman transition in the system and switches its electronic state. We confirm this through microwave response to a continuous probe field, observing near-perfect (99.7%) extinction of the reflection and highly efficient (74%) frequency down-conversion. These proof-of-principle results lead to deterministic quantum gates between material qubits and microwave photons and open the possibility for scalable quantum networks interconnected with waveguide photons.

Excellent results of high-dose mizoribine combined with cyclosporine, basiliximab, and corticosteroids in renal transplant recipients--4-year results

BACKGROUND

Mizoribine (MZR) at 3 mg/kg/d shows less potent immunosuppressive effects, but high-dose MZR (6 mg/kg/d) was effective and safe in a 2-year study in conjunction with a regimen of cyclosporine (CsA), basiliximab, and corticosteroids.

METHODS

We compared 40 living-related kidney recipients administered MZR (6 mg/kg/d), CsA (7 mg/kg/d), prednisolone (maintenance dose 10 mg/d), and basiliximab (20 mg/body) with control group (n = 38) treated with CsA, mycophenolate mofetil (MMF; 25 mg/kg/d), basiliximab, and corticosteroids.

RESULTS

The 4-year graft survival rates for the MZR vs MMF groups were 92.5% vs 94.7%, respectively, with serum creatinine levels of 1.66 ± 1.0 mg/dL vs 1.41 ± 0.42 mg/dL at 3 years, and 1.72 ± 1.16 mg/dL vs 1.56 ± 1.26 mg/dL at 4 years. There was no significant difference in serum creatinine levels between the 2 groups. The MZR group demonstrated a significantly higher rate of elevated serum uric acid values (29.7%). The numbers of patients treated with allopurinol at 4 years were 11/37 (29.7%) for MZR vs 2/36 (5.6%) for the MMF subjects (P < .05). Mean serum uric acid levels of the MZR vs MMF group at 4 years were 7.1 ± 1.9 mg/dL vs 7.0 ± 1.6 mg/dL, respectively (NS). There was no significant difference between the 2 groups regarding bone marrow suppression or liver dysfunction. Severe cytomegalovirus infection was not observed at 3 and 4 years in either group. There were no severe gastrointestinal symptoms among the MZR or the MMF group at 3 or 4 years.

CONCLUSIONS

The combination of high-dose MZR with CsA, basiliximab, and corticosteroids displayed excellent results over a 4-year follow-up.

Observation of the three-state dressed states in circuit quantum electrodynamics

We have investigated the microwave response of a transmon qubit coupled directly to a transmission line. In a transmon qubit, owing to its weak anharmonicity, a single driving field may generate dressed states involving more than two bare states. We confirmed the formation of three-state dressed states by observing all of the six associated Rabi sidebands, which appear as either amplification or attenuation of the probe field. The experimental results are reproduced with good precision by a theoretical model incorporating the radiative coupling between the qubit and the microwave.

A case of living-donor renal transplantation for chronic renal failure caused by secondary amyloidosis

In Japan, amyloidosis is a rare cause of renal failure and of renal transplantation. We treated a patient who underwent a renal transplantation because of chronic renal failure caused by secondary amyloidosis with a good result. The patient was a 50-year-old woman who was diagnosed with secondary amyloidosis and an amyloid kidney. She underwent living donor renal transplantation after about 7 years of hemodialysis. During the 3-year posttransplantation period, she maintained good allograft function with a serum creatinine level about 1.2 mg/dL. Because of amyloidosis is a systemic disease, amyloid kidney patients often experience fatal complications, so the indications for renal transplantation in amyloid patients are still controversial. But if the patient's general condition is good, renal transplantation can be an effective therapy for patients with kidney failure caused by amyloidosis.

Rare spontaneous remission of hepatic artery aneurysm following ABO incompatible living donor liver transplantation: a case report

A 60-year-old male patient with an unknown cause for cirrhosis and a hepatoma underwent an ABO incompatible living donor liver transplantation (LDLT) from his son. The transplanted graft was his son's right lobe. For ABO incompatible transplantation, splenectomy was performed for desensitization. A catheter was inserted into the recipient's right hepatic artery for subsequent local immunosuppression. On the 15th postoperative day, a fusiform 15 × 10 mm aneurysm was observed in the graft right hepatic artery using ultrasonography and hepatic arteriography. At that time, the patient was also diagnosed to have an intraperitoneal abscess at the bottom of his left diaphragm. Administering antibiotics, we tried to embolize the aneurysm because of fear of rupture, but this manever failed because it was difficult to insert the wire in to the aneurysm to produce a stenosis around its proximal neck. However, because the aneurysm was not detectable on the 37th postoperative day, it was assumed to have embolized spontaneously. This relatively rare case revealed a hepatic artery aneurysm that spontaneously regressed after ABO incompatible LDLT.

Relationship between the Acid-Inhibitory Effects of Two Proton Pump Inhibitors and CYP2C19 Genotype in Japanese Subjects: A Randomized Two-Way Crossover Study

This two-way crossover study investigated possible differences between the proton pump inhibitors, omeprazole and rabeprazole, in their effect on gastric acid secretion in Japanese subjects with differing cytochrome P450, family 2, subfamily C, polypeptide 19 (CYP2C19) genotypes. A total of 23 Helicobacter pylori-negative healthy volunteers received omeprazole 20 mg/day and rabeprazole 10 mg/day. Each drug treatment was given for a continuous 7-day period allocated in random order, with an interval of at least 1 week between drug treatment periods to allow for wash-out. Intragastric pH was measured on days 1 and 7. Overall median intragastric pH levels at 7 and 8 h after the first administration were significantly higher with omeprazole. There was no significant difference in intragastric pH in homozygous extensive metabolizers, whereas intragastric pH was significantly higher with omeprazole in combined data from heterozygous extensive metabolizers and poor metabolizers at 6, 7 and 8 h after the first drug administration. There were no significant differences in intragastric pH between omeprazole and rabeprazole irrespective of genotype on day 7 of administration. In conclusion, on day 1 the time to onset of the antisecretory action of 20 mg/day omeprazole was more rapid than that of 10 mg/day rabeprazole in Japanese individuals who have a higher incidence of the CYP2C19 poor metabolizer genotype, however by day 7 no difference in antisecretory effect was found, regardless of genotype.

A comparative study of intragastric acidity during post-breakfast and pre-dinner administration of low-dose proton pump inhibitors: a randomized three-way crossover study

BACKGROUND

The absorption and bioavailability of proton pump inhibitors is influenced by food intake. Proton pump inhibitors bind to the parietal cell active proton pump, which is maximally stimulated after dinner: usually the largest meal of the day. However, it has not been fully clarified whether the efficacy of proton pump inhibitors differs between post-breakfast and pre-dinner dosing.

AIM

To perform a pH-monitoring study to clarify this issue for two low-dose proton pump inhibitors.

SUBJECTS AND METHODS

The subjects were 20 healthy male volunteers (seven Helicobacter pylori-positive and 13 H. pylori-negative), who were divided into two groups of 10 and administered 15 mg lansoprazole or 10 mg rabeprazole, respectively. All subjects underwent ambulatory intragastric 24-h pH- monitoring under three conditions allocated randomly: (i) without medication, (ii) seventh day of post-breakfast administration and (iii) eighth day of pre-dinner administration of each drug.

RESULTS

There was no significant difference in the percentage time during which pH > or =4.0 in the 24-h period between post-breakfast and pre-dinner administration of both drugs (56.6% vs. 55.8%; P = 0.557), although intragastric acidity during administration of both drugs was significantly lower than that without medication.

CONCLUSIONS

The timing of drug administration does not significantly influence the efficacy of low-dose proton pump inhibitors.

Interobserver agreement on classifying endoscopic diagnoses of nonerosive esophagitis

BACKGROUND AND STUDY AIMS

The majority of patients with gastroesophageal reflux disease in Japan have low-grade esophagitis, including minimal changes. A modified Los Angeles classification of esophagitis, consisting of erosive esophagitis (grades A - D) and nonerosive esophagitis (grades M and N) has been proposed and is in clinical use in Japan. However, it is unclear whether nonerosive esophagitis with only undemarcated mucosal discoloration (grade M) is clinically significant, since interobserver variations in classification have not been investigated. The aim of the present study was therefore to evaluate interobserver variance and diagnostic agreement in the diagnosis of nonerosive esophagitis (grades M and N).

MATERIALS AND METHODS

A total of 84 endoscopists were enrolled to assess the grade of esophagitis in 30 patients by viewing endoscopic images of the gastroesophageal junction. The images were projected onto a screen, and all of the endoscopists reviewed them concurrently. The diagnosis was selected from the following three categories in the modified Los Angeles classification: grades N, M, or A. The endoscopists were grouped according to their experience, whether they had a board license, and whether they had received specialist training in esophagitis. The kappa coefficient of reliability was calculated.

RESULTS

The kappa coefficient of reliability for all the endoscopists in the diagnosis of cases of grade M and N nonerosive esophagitis was unacceptably low at 0.22 (95 % CI, 0.21 - 0.24). Endoscopists with a board license and those who had completed a special esophagitis diagnostic course had slightly higher kappa values (0.26; 95 % CI, 0.23 - 0.30 and 0.29; 95 % CI, 0.26 - 0.32), respectively.

CONCLUSIONS

Interobserver agreement on the endoscopic diagnosis of nonerosive esophagitis (grades M and N) is too low to be of clinical value.

Evaluation of modified crystal violet chromoendoscopy procedure using new mucosal pit pattern classification for detection of Barrett's dysplastic lesions

BACKGROUND

Pit pattern diagnosis is important for endoscopic detection of dysplastic Barrett's lesions, though using magnification endoscopy can be difficult and laborious. We investigated the usefulness of a modified crystal violet chromoendoscopy procedure and utilised a new pit pattern classification for diagnosis of dysplastic Barrett's lesions.

METHODS

A total of 1,030 patients suspected of having a columnar lined oesophagus were examined, of whom 816 demonstrated a crystal violet-stained columnar lined oesophagus. The early group of patients underwent 0.05% crystal violet chromoendoscopy, while the later group was examined using 0.03% crystal violet with 3.0% acetate. A targeted biopsy of the columnar lined oesophagus was performed using crystal violet staining after making a diagnosis of closed or open type pit pattern with a newly proposed system of classification. The relationship between type of pit pattern and histologically identified dysplastic Barrett's lesions was evaluated.

RESULTS

Dysplastic Barrett's lesions were identified in biopsy samples with an open type pit pattern with a sensitivity of 96.0%. Further, Barrett's mucosa with the intestinal predominant mucin phenotype was closely associated with the open type pit pattern (sensitivity 81.9%, specificity 95.6%).

CONCLUSIONS

The new pit pattern classification for diagnosis of Barrett's mucosa was found to be useful for identification of cases with dysplastic lesions and possible malignant potential using a crystal violet chromoendoscopic procedure.

Dynamical aspects of the photoinduced phase transition in spin-crossover complexes

We report a dynamical study on the photoinduced cooperative changes of the spin configurations in single crystals of the organometal spin-crossover complex. In the photoswitching process between low- and high-spin states, nonlinear characteristics such as thresholdlike behavior, incubation period, and phase separation have been observed. These results demonstrate that the cooperative intersystem crossing mediated by spin-lattice interaction plays a key role in the driving process of a new class of nonequilibrium phenomena so called photoinduced phase transition.

Significance of stem cell factor and soluble KIT in patients with systemic lupus erythematosus

To determine the significance of stem cell factor (SCF) and soluble KIT (sKIT) in the serum of patients with systemic lupus erythematosus (SLE), levels of SCF and sKIT in patients with SLE were estimated, and their correlations with clinical parameters were examined. The sKIT levels in SLE patients (n = 106) were significantly lower than those in healthy controls (n = 40). A significant negative correlation was found between the SCF and sKIT levels of SLE patients. Although the SCF levels correlated with the titre of anti-RNP antibody, no significant relationship was found between SCF levels and blood cell counts, such as white blood cell, red blood cell and platelet counts. sKIT levels were significantly correlated with the platelet count, and were negatively correlated with the white blood cell count, titre of anti-DNA antibody, and SLE activity index (SLEDAI). sKIT levels were also negatively affected by high doses of corticosteroid. These results indicate that serum sKIT levels may be more closely related than SCF to the haematological abnormalities in SLE patients, and may reflect the clinical status of SLE patients and the effectiveness of high-dose corticosteroid treatment.

Inhibitory effect of the immunosuppressant FK506 on apoptotic cell death induced by HIV-1 gp120

Human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 may play a central role in inducing immunoregulatory disorders after HIV infection. The apoptotic death of normal human peripheral blood mononuclear cells was induced by priming with gp120 followed by stimulation with an anti-T cell receptor (TCR) antibody. Tumor necrosis factor-alpha produced by gp120-binding macrophages may be important to induce this cell death. Treatment of gp120-primed cells with an immunosuppressant (FK506) before TCR signaling inhibited apoptotic cell death, and this blocking effect of FK506 was concentration dependent. FK506 did not have any influence on cell growth and viability over the range of concentrations tested. These findings suggest that FK506 is a potentially useful drug in delaying the onset of AIDS after HIV infection.

Mixed cavernous angioma and glioma (angioglioma) in the hypothalamus--case report

A 54-year-old female presented with a huge mixed cavernous angioma and astrocytoma in the hypothalamus manifesting as headache, visual field defect, gait disturbance, and convulsion. Radiological studies revealed a huge suprasellar tumor encasing all the major cerebral vessels. Craniotomy disclosed a hemorrhagic tumor poorly demarcated from the surrounding brain which was partially removed. Histological examination of the operative specimen revealed cavernous angioma with low grade glioma in the periphery. The residual tumor responded to radiation therapy remarkably well. An autopsy conducted 3 years later revealed a small hypothalamic astrocytoma with abundant vasculature.

Detection of antibodies to HIV-1 gp41- and HLA class II antigen-derived peptides in SLE patients

A role for viruses in the pathogenesis of human autoimmune diseases has long been suspected but has not yet been proven. Highly conserved homologous regions has been reported in the carboxy terminus of human immunodeficiency virus (HIV)-1 gp41 (amino acids 838-844) and the amino-terminal of the beta chain of all human HLA class II antigens (amino acids 19-25). This molecular mimicry between HIV-1 and HLA class II antigens may lead to the generation of autoantibodies and may contribute to the development of autoimmune phenomena in HIV infected patients. We detected antibodies for these homologous peptides from HLA class II and HIV-1 gp41 in systemic lupus erythematosus (SLE) patients without HIV-1 infection. Thirty-seven percent of the SLE patients had IgM antibodies reacting with both HLA class II- and HIV-1 gp41-derived peptides. These results suggest the possibility that a retrovirus may be one of the causative agents of SLE.

Amino acids and peptides. XX. Preparation of beta-cyclododecyl aspartate and its application to synthesis of fibronectin- and laminin-related peptides

beta-Cyclododecyl aspartate was prepared and its application to peptide synthesis was examined. Derivatives of beta-cyclododecyl aspartate are more likely to crystallize and should be useful for peptide synthesis. The cyclododecyl ester was much stable to bases than the benzyl ester and rather more stable than the cyclohexyl ester. It was removable by HF treatment and trifluoromethanesulfonic acid treatment. beta-Cyclododecyl aspartate was used for synthesis of laminin- and fibronectin-related peptides by solid phase and liquid phase methods.

[Acute relapsing disseminated encephalomyelitis (ARDEM) mimicking a temporal lobe tumor]

A case of ARDEM presenting as a temporal lobe tumor is reported. A 19-year-old male was admitted to the hospital, because of headache, right homonymous hemianopsia, and general convulsion. CT scan and MR imaging revealed localized right medial temporal enhanced mass lesion with surrounding brain edema. The craniotomy revealed an elastic hard ill-defined subcortical tumor. Histology showed a demyelinating process with perivascular lymphocyte cuffings. The patients' postoperative course was essentially uneventful until the 7th day when he developed fever, persistent hiccup, vertigo followed by obtundation and respiratory distress. Repeated MR imaging revealed extensive lesions in the left thalamus, brain stem, upper spinal cord and cerebellum. The patient responded to steroid pulse therapy well. Six months later, however, he returned to the hospital with severe memory disturbance. Repeated MR imaging showed diffuse bilateral parieto-occipital white matter lesions. He again responded to steroid pulse therapy well. An immunosuppressant Mizoribine was added to his steroid therapy to prevent recurrence. With the advent of MR imaging, more non-surgical diseases such as multiple sclerosis and Behçet disease are visualized on imaging study. The differentiation of these diseases from intraparenchymal neoplasm is difficult when they present as a single mass lesion. ADEM or ARDEM should be included in the list of such lesions requiring differential diagnosis.

[Myelin basic protein in the cerebrospinal fluid of patients with neurological disease: especially with malignant brain tumors]

Myelin basic protein (MBP) in the cerebrospinal fluid (CSF) of patients with brain tumors and other neurological diseases was measured before, during and after various treatments such as surgery, chemotherapy and irradiation. We assessed the significance of changes in the MBP levels during the course of treatment, and speculate on what the elevated level of MBP in brain tumor patients indicates. In meningeal dissemination of malignant tumors, meningeal carcinomatosis from cancer of the systemic organ showed the highest level of MBP followed by meningeal gliomatosis and meningeal lymphoma. Meningeal carcinomatosis and meningeal lymphoma, which have responded to chemotherapy, showed normal levels of MBP after chemotherapy. Six of eight patients with newly diagnosed malignant glioma showed moderate to high levels of MBP (range 4.6-35.5ng/ml) just before intraarterial chemotherapy with VP-16 and CDDP. The level increased in five patients during the course of chemotherapy and then decreased in relation to the degree of tumor reduction by chemotherapy. In the solid type of metastatic brain tumor, five of seven patients with multiple tumors showed high levels of MBP and these levels also returned to normal after treatment in four patients. As for the influence of irradiation, levels of MBP did not increase after irradiation except in three patients who developed radiation necrosis, local extensive edema or atrophic change. In other brain tumors, levels of MBP were high in a patient with a large meningioma with very extensive edema and during an unstable postoperative condition after total removal of a large craniopharyngioma.(ABSTRACT TRUNCATED AT 250 WORDS)

Nontraumatic intradiploic arachnoid cysts--report of five cases

Five cases of nontraumatic intradiploic arachnoid cysts in elderly patients are reported. All cysts were located in the occipital bone and appeared as well-demarcated radiolucent lesions. The cysts were multiple in three cases. Presenting symptoms included headache or dizziness, but most lesions were asymptomatic and found incidentally. In the most recent three cases, magnetic resonance (MR) imaging revealed intradiploic cysts containing cerebrospinal fluid (CSF) with cerebellar herniation. Operation found the cysts filled with CSF and dural defects through which cerebellar tissue was herniating. In two patients, CSF leakage from the outer table occurred. Intradiploic arachnoid cyst seems to be congenital in origin but commonly found in the elderly. MR imaging is the most useful diagnostic method for differential diagnosis from other osteolytic skull lesions.

[Dysembryoplastic neuroepithelial tumor; a case report]

The authors report a case of dysembryoplastic neuroepithelial tumor which is a new entity of glial tumor proposed by Daumas-Duport et al. A 16-year-old male was admitted to our hospital with a 5-year history of uncontrollable complex partial seizure. CT scan showed a non-enhanced homogeneous low density area without mass effect, simulating old infarction or porencephalic cyst in the right posterior temporal lobe. The inner table of the skull over the lesion was eroded. The lesion showed low signal intensity in T1 weighted MR image and high signal intensity in T2 image. Craniotomy disclosed greyish soft solid tumor without cyst. Histologically, the tumor contained multiple cellular nodules in the microcystic astrocytic part which contained neurons. After the surgery the patient was free from the seizure. Dysembryoplastic neuroepithelial tumor is found in young patients with intractable partial seizures. It is characterized by pseudocystic well-demarcated low density appearance on CT scan. Histologically, it is an intracortical multinodular heterogeneous tumor which, is surgically treatable with favorable prognosis. For differential diagnosis, this tumor must be recognized in the list of low-density intracranial lesions found during CT scan.

[One stage removal of huge glomus tumor]

Surgical removal of a huge glomus jugular tumor has been considered as one of the most difficult skull base surgeries not only because of the difficulty in approaching the tumor, but also because of its highly vascular nature and various possible postoperative complications. We used combined infratemporal fossa and lateral suboccipital approach in a single stage to operate on a 49-year-old male with a huge glomus jugular tumor, which extended from the right cerebellopontine angle to the level of the the third vertebra. With this approach we could expose the tumor extensively and control the feeding arteries easily in spite of marked vascularity of the tumor. Retraction of the cerebellum was only minimal owing to the removal of the petrous bone. The tumor was excised not by piecemeal but in en block manner with preservation of all the cranial nerves but the glossopharyngeal nerve. To prevent postoperative cerebrospinal fluid leakage, the following procedures were very useful; 'blind sack closure' of the external auditory canal, careful closure of the Eustachian tube, use of the pedicled muscle flap from the temporal and the sternocleidomastoid muscle, use of fibrin glue at the time of the wound closure, and placement of preventive spinal drainage. The patient was discharged with hoarseness and facial palsy. However these symptoms had almost completely disappeared within one year. He is working in the same occupation as before.

New Secoiridoid Glucosides from Ligustrum japonicum

Two new secoiridoid glucosides, oleonuezhenide and isonuezhenide, have been isolated along with known secoiridoid glucosides, from the fruits of LIGUSTRUM JAPONICUM. Their structures have been elucidated on the basis of chemical and spectral data.

[Cortical somatosensory evoked potential associated with experimental chronic cord compression by epidural neoplasm in rabbits]

An experimental model of spinal cord compression was developed in rabbits by epidural neoplasms which were injected anterior to the T 13 vertebral body and grew into the spinal canal through the intervertebral foramina. With this experimental model, the neurological condition of the animals was monitored using a scale and changes of somatosensory evoked potentials (SEPs) were studied to evaluate the neurophysiological effect of experimental chronic cord compression. The animals were immobilized with pancuronium bromide and artificial respiration was maintained through a tracheostomy. SEPs were recorded by silver ball electrodes which were positioned epidurally over the somatosensory cortex through small burr holes. A subcutaneous needle placed at the nose served as a reference electrode. Right hind paw was stimulated via two percutaneous needles with 0.1 msec rectangular impulses sufficiently strong to produce motor responses, ranging from 10 to 20 volt in control rabbits. Electrical stimuli were delivered at a rate of 1 Hz. The intensity of electrical stimulation was raised up to 300 volt, when no consistent SEP was observed in the rabbit with spinal neoplasm. The SEP was summated by averaging 50 successive cortical transients with the analysis time of 200 and 500 msec. The cortical SEPs in the rabbit normally consisted of a positive-negative sequence, which we labelled P1, N1, P2, N2 and so on. Early peaks, P1 and N1, were observed constantly with average latencies of 30.1 and 53.3 msec respectively in normal rabbits. The variability of amplitudes seen even in control animals made them a less useful measure of function than latencies. Normal SEPs were preserved until the animals demonstrated moderate paraparesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinicoanatomical study of thalamic stimulation for pain relief

Our small experiences with electrical stimulation in the VPL and VPM for dysesthetic pain show that it provoked only paresthesia and induced some relief of pain. It does not increase the beta-endorphin level in CSF. To clarify the anatomical substrata in VPL stimulation, neuroanatomical studies were done about the inputs to VPL in man, monkey and cat by the Fink-Heimer method. The spinothalamic tract terminates in VPL in a patchy fashion in the monkey. The corticothalamic fibers from SI and SII cortex project to VPL and VPM in somatotopical organization in the cat. SI and SII cortices have reciprocal connections, in addition to projections to area 5 or SIII cortex. The corticofugal fibers to the magnocellular and gigantocellular tegmental fields are suggested in addition to the dorsal column nuclei, spinal trigeminal nuclei and spinal posterior horn in cat. The medial lemniscus input to VPL and the above neural circuits are thought to be associated with VPL stimulation.

Therapeutic occlusion of the vertebral artery for unclippable vertebral aneurysm: relationship between site of occlusion and clinical outcome

Six cases of unclippable vertebral aneurysms were treated by therapeutic occlusion of the proximal vertebral artery. In three cases, the vertebral artery was clipped proximal to the posterior inferior cerebellar artery (PICA), and all of these patients had a postoperative embolic complication or a fatal subarachnoid hemorrhage. In two cases, the vertebral artery was clipped distal to the PICA and in one case the PICA was absent and the vertebral artery was clipped proximal to the aneurysm. All three of these patients did well without any neurological deficit. Possible mechanisms of the complications are discussed, and the importance of not clipping the PICA is stressed.

[Germ cell tumor in the basal ganglia with elevated serum and CSF alpha-fetoprotein levels]

Intracranial germ cell tumors usually locate either in the pineal region or in the suprasellar region or both. Primary occurrence of germ cell tumor in the basal ganglia is rare. To our knowledge, only 17 cases have been reported in the literatures, and all the patients were Japanese. None of these patients presented elevated serum and CSF AFP levels in the literatures. We are reporting a patient with a germ cell tumor which developed in the left basal ganglia and showed high serum and CSF alpha-fetoprotein (AFP) levels. The patient was a 12-year-old boy who had been completely well until five months prior to the first admission when he developed weakness of right extremities. On admission he showed a right hemiparesis of mild degree and right hypesthesia. CT-scans demonstrated a homogeneous high density area over the caudate head and the putamen on the left side. The anterior limb of the left internal capsule and a part of the posterior limb were also involved. The lesion was moderately enhanced by the contrast medium. Stereotaxic biopsy of the lesion was uncontributory and he was discharged for follow up. Five months later, CT-scans demonstrated the enlargement of the high density area with perifocal edema. Then we performed a craniotomy, and the tumor which was soft and dark red in colour was biopsied at the wall of the anterior horn of the left lateral ventricle. Histopathology of the specimen showed germinoma of two-cell pattern.(ABSTRACT TRUNCATED AT 250 WORDS)