Efficacy and Safety of Cilostazol in Mild Cognitive Impairment: A Randomized Clinical Trial

Importance

Recent evidence indicates the efficacy of β-amyloid immunotherapy for the treatment of Alzheimer disease, highlighting the need to promote β-amyloid removal from the brain. Cilostazol, a selective type 3 phosphodiesterase inhibitor, promotes such clearance by facilitating intramural periarterial drainage.

Objective

To determine the safety and efficacy of cilostazol in mild cognitive impairment.

Design, Setting, and Participants

The COMCID trial (A Trial of Cilostazol for Prevention of Conversion from Mild Cognitive Impairment to Dementia) was an investigator-initiated, double-blind, phase 2 randomized clinical trial. Adult participants were registered between May 25, 2015, and March 31, 2018, and received placebo or cilostazol for up to 96 weeks. Participants were treated in the National Cerebral and Cardiovascular Center and 14 other regional core hospitals in Japan. Patients with mild cognitive impairment with Mini-Mental State Examination (MMSE) scores of 22 to 28 points (on a scale of 0 to 30, with lower scores indicating greater cognitive impairment) and Clinical Dementia Rating scores of 0.5 points (on a scale of 0, 0.5, 1, 2, and 3, with higher scores indicating more severe dementia) were enrolled. The data were analyzed from May 1, 2020, to December 1, 2020.

Interventions

The participants were treated with placebo, 1 tablet twice daily, or cilostazol, 50 mg twice daily, for up to 96 weeks.

Main Outcomes and Measures

The primary end point was the change in the total MMSE score from baseline to the final observation. Safety analyses included all adverse events.

Results

The full analysis set included 159 patients (66 [41.5%] male; mean [SD] age, 75.6 [5.2] years) who received placebo or cilostazol at least once. There was no statistically significant difference between the placebo and cilostazol groups for the primary outcome. The least-squares mean (SE) changes in the MMSE scores among patients receiving placebo were -0.1 (0.3) at the 24-week visit, -0.8 (0.3) at 48 weeks, -1.2 (0.4) at 72 weeks, and -1.3 (0.4) at 96 weeks. Among those receiving cilostazol, the least-squares mean (SE) changes in MMSE scores were -0.6 (0.3) at 24 weeks, -1.0 (0.3) at 48 weeks, -1.1 (0.4) at 72 weeks, and -1.8 (0.4) at 96 weeks. Two patients (2.5%) in the placebo group and 3 patients (3.8%) in the cilostazol group withdrew owing to adverse effects. There was 1 case of subdural hematoma in the cilostazol group, which may have been related to the cilostazol treatment; the patient was successfully treated surgically.

Conclusions and Relevance

In this randomized clinical trial, cilostazol was well tolerated, although it did not prevent cognitive decline. The efficacy of cilostazol should be tested in future trials.

Trial Registration

ClinicalTrials.gov Identifier: NCT02491268.

First evidence of tick-borne encephalitis (TBE) outside of Hokkaido Island in Japan

Tick-borne encephalitis (TBE) is an infection of the central nervous system caused by the tick-borne encephalitis virus (TBEV). TBE is endemic in parts of Europe and Asia. TBEV is transmitted to humans primarily by Ixodes ticks. There have been 5 TBE cases identified in Japan, all on the northern island of Hokkaido. Rodents with TBEV antibodies and Ixodes ticks have been identified throughout Japan, indicating that TBEV infection might be undiagnosed in Japan. Residual serum and cerebrospinal fluid (CSF) collected in 2010-2021 from 520 patients ≥1 year-of-age previously hospitalized with encephalitis or meningitis of unknown etiology at 15 hospitals (including 13 hospitals outside of Hokkaido) were screened by ELISA for TBEV IgG and IgM antibodies; TBEV infection was confirmed by the gold standard neutralization test. Residual serum was available from 331 (63.6%) patients and CSF from 430 (82.6%) patients; both serum and CSF were available from 189 (36.3%). Two patients were TBE cases: a female aged 61 years hospitalized for 104 days in Oita (2000 km south of Hokkaido) and a male aged 24 years hospitalized for 11 days in Tokyo (1200 km south of Hokkaido). Retrospective testing also identified a previous TBEV infection in a female aged 45 years hospitalized for 12 days in Okayama (1700 km south of Hokkaido). TBEV infection should be considered as a potential cause of encephalitis or meningitis in Japan. TBE cases are likely undiagnosed in Japan, including outside of Hokkaido, due to limited clinical awareness and lack of availability of TBE diagnostic tests.

White Embolus-induced Basilar Artery Occlusion Due to Pulmonary Vein Invasion of a Metastasis of a Malignant Melanoma

An 80-year-old woman presented with impaired consciousness after malignant melanoma resection. Magnetic resonance angiography showed basilar artery occlusion, which was subjected to mechanical thrombectomy for recanalization. A pathological analysis of the retrieved embolus revealed that it was derived from a metastasis of malignant melanoma. Contrast-enhanced chest computed tomography showed multiple pulmonary metastases, one of which was in the right upper lobe and invaded the pulmonary vein. To our knowledge, this is the first case of white embolus-induced cerebral embolism due to pulmonary vein invasion of a metastasis of a pathologically diagnosed malignant melanoma.

Japanese spotted fever with post-infectious encephalitis

Japanese spotted fever (JSF) is a rickettsial disease caused by Rickettsia japonica. To the best of our knowledge, there have only been five reported cases of JSF involving the central nervous system. A 74-year-old man was admitted after 1 week of fever and maculopapular rash. JSF was definitively diagnosed by PCR; however, the patient showed mental disturbance and abnormal behavior. After intravenous immunoglobulin, his mental state and behavior improved. The findings of cerebrospinal fluid analysis, electroencephalography, and ^99 mTcHM-PAO single photon computed emission tomography suggested post-infectious encephalitis. JSF causes post-infectious encephalitis and early treatment is recommended.

Serial assessment of multimodality imaging in anti-leucine-rich glioma-inactivated 1 antibody encephalitis: A case report

In autoimmune encephalitis, abnormalities of diffusion-weighted imaging (DWI), fluid-attenuated inversion recovery (FLAIR), arterial spin labeling (ASL) in magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT) and ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG-PET) have been reported. However, there are few studies of long-term follow-up of imaging. We report a case of anti-leucine-rich glioma-inactivated 1 antibody encephalitis whose MRI (DWI, FLAIR and ASL), ^99mTcHM-PAO SPECT (PAO-SPECT) and ¹⁸F-FDG-PET were evaluated through the clinical course. ASL, PAO-SPECT and ¹⁸F-FDG-PET consistently showed abnormalities in almost the same area. Serial assessment of these imaging modalities is useful in evaluating disease activity and efficacy of treatment.

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We followed up anti-LGI1 encephalitis by comparing multimodality imaging.

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ASL, PAO-SPECT and ¹⁸F-FDG-PET showed similar trends of abnormalities.

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Serial assessment of imaging was useful in evaluating disease activity.

Short-term aneurysm formation and rupture due to septic embolism diagnosed with a thrombus retrieved from another occluded artery

Background:

In rare cases, septic embolism is diagnosed on the basis of pathological findings of retrieved thrombi. Infected aneurysms can rapidly form and rupture after septic embolism, leading to a poor prognosis. We report a case of subcortical hemorrhage due to an infected aneurysm forming shortly after septic embolism in the left anterior cerebral artery.

Case Description:

In this case, the diagnosis of septic embolism was made on the basis of pathological findings of a thrombus retrieved from the simultaneously occluded left middle cerebral artery, and endovascular embolization of the infected aneurysm was performed.

Conclusion:

The pathological findings of a retrieved thrombus were useful for making a diagnosis of septic embolism. The possibility of short-term formation and rupture of an infected aneurysm after septic embolism should be noted. Endovascular embolization of occluded vessels due to septic embolism may prevent aneurysm formation and subsequent bleeding.

[Myelomatous meningitis: a case report]

We present the case of a 67-year-old woman with meningeal carcinomatosis who was treated with chemotherapy for refractory multiple myeloma, and was in remission. She was admitted to our hospital because of tonic seizures and disturbance of consciousness. Monoclonal CD 138-positive plasma cells were detected in her cerebrospinal fluid. Cranial MRI showed gadolinium enhancement of diffuse meninges and cranial nerves. We diagnosed the patient with systemic epilepsy due to meningeal carcinomatosis and administered antiepileptic drugs and intrathecal chemotherapy; however, she showed little improvement, and she passed away on hospital day 74 because of disease progression. Multiple myeloma is known to be associated with neurological symptoms such as peripheral neuropathy, myelopathy, and radiculopathy; however, central nervous system involvement in multiple myeloma is uncommon. We should consider central nervous system involvement in multiple myeloma, such as meningeal carcinomatosis, given the importance of early detection and therapeutic intervention.

[Tetanus: the clinical features of 11 cases]

Tetanus is an infectious disease induced by wound invasion of Clostridium tetani, which is ubiquitous among soil. Many more cases are reported in Japan than in other developed countries. In this study, we report 11 cases of tetanus experienced at our hospital and discuss the preceding trauma and treatment course. The mean age at onset was 68 years old (35-86 years) and 7 cases required intensive care. Some preceded injuries were clearly contaminated, and others were small and minor. Even minor injuries developed serious tetanus. Trauma was not identified in 2 cases yet both used their family garden every day and had a high risk of exposure to C tetani, suggesting that micro-wounds may have been a gateway to entry. The average length of stay in the intensive care unit was 28 days (4-73 days) and average total hospitalization was 55 days (13-114 days). Only 4 out of 11 cases were diagnosed correctly by the initial physician and others, especially when the trauma was minor or absent, were misdiagnosed even when presenting with characteristic symptoms like lockjaw and posterior neck stiffness. Tetanus should be diagnosed based on medical history and physical examination due to lack of high specific testing. Therefore, a detailed history taking is required, including hobbies in addition to the appropriate neurological examination, thereby facilitating a quick diagnosis and commencement of treatment as soon as possible.

Branch atheromatous disease has a stronger association with late-onset epileptic seizures than lacunar infarction in Japanese patients

Objective

To evaluate the relationship between late-onset epileptic seizures and non-cortical infarction (namely, lacunar infarction and branch atheromatous disease [BAD]) in Japanese patients.

Methods

We reviewed the medical records and brain magnetic resonance imaging findings of all patients with ischemic stroke admitted to the Departments of Neurology, Neurosurgery, and Stroke Unit at Kurashiki Central Hospital from 1 January 2011 to 31 December 2012. Patients with lacunar infarction and BAD were enrolled; those with cortical and brain stem ischemic lesions were excluded. We analyzed the clinical features of patients who developed late-onset epileptic seizures after cerebral infarction.

Results

Eighty-five patients with lacunar infarction and 99 patients with BAD were enrolled. Four patients with BAD subsequently developed epileptic seizures (2.2% of total patients, 4.0% of patients with BAD), whereas no patients with lacunar infarction developed epileptic seizures. All patients with epileptic seizures had infarction involving the basal ganglia or thalamus. Three of them had multiple cerebral microbleeds, and two had dementia.

Conclusions

Patients with BAD, but not with lacunar infarction, might have a higher risk of developing epileptic seizures than the general population. Non-cortical infarctions with involvement of the basal ganglia or thalamus may increase the risk of subsequent late-onset epileptic seizures.

Certified Reference Material for Analytical Quality Assurance of Minor and Trace Elements in Food and Related Matrixes Based on a Typical Japanese Diet: Interlaboratory Study

A Certified Reference Material (CRM) was prepared at the National Institute for Environmental Studies (NIES), Japan, in collaboration with the National Institute of Radiological Sciences (NIRS), Japan, for the analytical quality assurance of minor and trace elements in food and related matrixes. The starting material for the CRM was all food served in 29 households in Japan over two 3-day periods in 1997–1998, and thus the CRM represented a typical Japanese diet. All foods (meals, snacks, and beverages) were homogenized, freeze-dried, pulverized, blended, dispensed into 1100 bottles, and sterilized. The within- and between-bottle homogeneity of the prepared CRM was satisfactory for most of the elements. The concentrations of 14 elements (Na, Mg, K, Ca, Mn, Cu, Zn, As, Se, Sr, Cd, Sn, Ba, and U) were certified based on a collaborative analysis involving NIES, NIRS, and 20 other laboratories. Reference values were given for the concentrations of 12 additional elements (P, Cl, Fe, Co, Ni, Br, Rb, Mo, I, Cs, Pb, and Th). The elements certified and those given reference values include minerals, essential trace elements, contaminant elements, and long-lived radionuclides. Thus, this CRM is of practical value in the quality assurance of element analysis of foods and diets in nutritional, environmental, and radiological research.

[Primary angiitis of the central nervous system with cerebral infarction and spinal hemorrhage]

A 61-year-old woman presented with acute intense lower back pain and weakness in her left leg. She also presented with throbbing headache on the same day. On admission, muscle weakness in her left leg, lower left quadrantanopia and left lower extremity deep sensory disturbance were observed. Laboratory data showed no coagulopathy and autoimmune antibody was negative. Cerebrospinal fluid examination showed bloody and inflammatory findings. Brain MRI revealed cerebral infarction with multiple intracranial arterial stenosis and convexal subarachnoid hemorrhage. Spinal MRI revealed spinal hemorrhage in the cervical, thoracic, and part of the lumbar spine. Because these lesions occurred simultaneously, we made a diagnosis of vasculitis. After high dose corticosteroids therapy was undertaken, the multiple arterial stenosis improved. Primary angiitis of the central nervous system is sometimes difficult to distinguish from reversible cerebral vasoconstriction syndrome in its initial stage; although symptoms, examination findings and treatment differ in both.

Suvorexant-Induced Dream Enactment Behavior in Parkinson Disease: A Case Report

ABSTRACT

Suvorexant is a new insomnia drug, and it is generally safe and well tolerated. Here, we report a rare but potentially important adverse effect of suvorexant in a patient with Parkinson disease.

Open-label study to evaluate the pharmacodynamics, clinical efficacy, and safety of meropenem for adult bacterial meningitis in Japan

The aim of this study was to assess the efficacy, safety, and concentration of meropenem in cerebrospinal fluid when meropenem (2 g every 8 h) was administered to Japanese adult patients with bacterial meningitis. Five Japanese patients (mean age 60.6 years [range 35-71]) were enrolled. Infection with Streptococcus pneumoniae (three patients), Streptococcus salivarius (one patient), and Staphylococcus aureus (one patient) was confirmed by cerebrospinal fluid culture. Meropenem (2 g every 8 h) was administered to all five patients. Treatment duration ranged from 14 to 28 days (mean 22.6 days). All the patients were successfully treated. The concentration of meropenem in cerebrospinal fluid ranged from 0.27 to 6.40 μg/ml up to 8.47 h and was over 1 μg/ml 3 h after starting meropenem infusion. In each patient, the present study confirmed for the first time that the concentration of meropenem in cerebrospinal fluid exceeded the minimal inhibitory concentration for these pathogens. Eleven clinical and laboratory adverse events considered to be related to meropenem were observed in all patients, but no serious adverse event and no discontinuance of treatment due to adverse events occurred. Thus meropenem appeared to be a well-tolerated and effective agent for Japanese adult patients with bacterial meningitis. 2 g every 8 h of meropenem was delivered to CSF and its concentration was exceed in MICs for the detected pathogens.

IL-28B (IFN-λ3) and IFN-α synergistically inhibit HCV replication

Genetic variation in the IL-28B (interleukin-28B; interferon lambda 3) region has been associated with sustained virological response (SVR) rates in patients with chronic hepatitis C treated with peginterferon-α and ribavirin. However, the mechanisms by which polymorphisms in the IL-28B gene region affect host antiviral responses are not well understood. Using the HCV 1b and 2a replicon system, we compared the effects of IFN-λs and IFN-α on HCV RNA replication. The anti-HCV effect of IFN-λ3 and IFN-α in combination was also assessed. Changes in gene expression induced by IFN-λ3 and IFN-α were compared using cDNA microarray analysis. IFN-λs at concentrations of 1 ng/mL or more exhibited concentration- and time-dependent HCV inhibition. In combination, IFN-λ3 and IFN-α had a synergistic anti-HCV effect; however, no synergistic enhancement was observed for interferon-stimulated response element (ISRE) activity or upregulation of interferon-stimulated genes (ISGs). With respect to the time course of ISG upregulation, the peak of IFN-λ3-induced gene expression occurred later and lasted longer than that induced by IFN-α. In addition, although the genes upregulated by IFN-α and IFN-λ3 were similar to microarray analysis, interferon-stimulated gene expression appeared early and was prolonged by combined administration of these two IFNs. In conclusion, IFN-α and IFN-λ3 in combination showed synergistic anti-HCV activity in vitro. Differences in time-dependent upregulation of these genes might contribute to the synergistic antiviral activity.

Age-related emotionality is associated with cortical delta-opioid receptor dysfunction-dependent astrogliosis

Multiple changes occur in the aging brain, leading to age-related emotional disorders. A growing body of recent evidence suggests that the cortical delta-opioid receptor system plays a critical role in anxiety- and depressive-like behaviors in the rodent. In this study, we show that aging mice promoted anxiety-like behaviors as characterized by both the light-dark and elevated plus-maze tests, and they exhibit an increase in astrocytes in the cingulate cortex due to the dysfunction of cortical delta-opioid receptor systems. As well as aging mice, mice with a dysfunction of the delta-opioid receptor system induced by chronic treatment with the selective delta-opioid receptor antagonist naltrindole, revealed astrogliosis in the cingulate cortex, which was associated with anxiety. We also found that the microinjection of cultured astrocytes into the cingulate cortex of young mice enhanced the expression of anxiety-like behavior. Our results indicate that the aging process promotes astrogliosis in the cingulate cortex through the dysfunction of cortical delta-opioid receptors. This phenomenon may lead to emotional disorders including aggravated anxiety during normal aging.

Kidney transplantation from non–heart-beating donors: Analysis of organ procurement and outcome

INTRODUCTION

Most donors in Japan have been non-heart-beating donors (NHBD), so-called "marginal donors." In Western countries kidney transplants from NHBD have also been increasing. We analyzed 120 kidneys harvested from NHBD with regard to organ procurement, renal function, graft survival, and the donor factors that affected graft survival.

METHODS

Donors were moved into the operating room after cardiac arrest. A double-balloon catheter was inserted into the abdominal aorta via laparotomy. In situ cooling by Euro-Collins solution was started at 500 mL/min. We did not performed cannulation into the femoral artery or vein prior to cardiac arrest.

RESULTS

Warm ischemia time (WIT) was 18.6 minutes. Among 108 kidneys (90%) used for transplantation, 102 kidneys functioned. There were no cases of bilateral nonfunctioning kidneys. The delayed graft function (DGF) rate was 86%; however, the death-censored graft survival was 80.0% at 5 years and 62.9% at 10 years. Kidneys implanted after more than 24 hours of total ischemia time required a significantly longer period of hemodialysis. Donor risk factors that affected graft survival included WIT >/= 20 minutes, donor age >/= 50 years, and serum creatinine level at admission > 1.0 mg/dL.

CONCLUSIONS

Organ procurement without cannulation prior to cardiac arrest entailed a long WIT and a high DGF rate. However, the graft survival was good. It has been necessary to use grafts from NHBD despite the inherent risk factors. It is important to reduce kidney damage both at the organ procurement and during the posttransplant management.

Outcomes of kidney transplants from non-heart-beating deceased donors as reported to the Japan Organ Transplant Network from April 1995-December 2003: a multi-center report

Between April 1995-December 2003, 1,324 deceased donor kidney transplantations were performed in 139 transplant institutes in Japan. Of these, 45 transplants were from heart-beating and 1,279 transplants were from non-heart-beating deceased donors (NHBDD). Clinical outcomes for the 1,279 recipients of NHBDD kidney transplants were investigated. The overall 5-year patient and graft survival rates were 90% and 72%, respectively. A total of 112 NHBDD kidney grafts never functioned after transplantation and the recipients had to remain on dialysis. The causes of nonfunction were rejection, primary nonfunction, death, thrombosis and others in the order of the incidence. The major causes of graft loss were nonfunction, death, chronic rejection and acute rejection in that order. Major causes of recipient deaths were pneumonia, sepsis and CVA within 12 months, and heart diseases, sepsis, malignancy and pneumonia more than 12 months after transplantation. Kidneys from female donors, donors aged 15 or less or over age 60, donors with extrinsic causes of death other than head trauma, recipients over age 60 and those with diabetic nephropathy as their original disease were found to be at risk for poor graft survival. The lowest and last donor serum creatinine level did not influence the incidence of nonfunction or graft survival. However, graft survival was significantly poorer among recipients of older "expanded" donor kidneys than for recipients of younger grafts. The warm and total ischemia times should be kept shorter than 30 minutes (better 15 minutes), and 12 hours, respectively to minimize the incidence of nonfunction and early graft loss. It is especially important in cases with WIT over 30 minutes that the total ischemia should be kept within 12 hours. Cannulation before cardiac standstill was important to reduce the incidence of nonfunction and achieve high graft survival rates with NHBDD kidneys. The discontinuance of ventilator support also reduced the incidence of graft nonfunction. The combination of CsA or Tacrolimus and MMF as both the induction and maintenance regimen significantly improved graft survival. The use of either anti-T cell antibodies or basiliximab was also associated with significantly better graft survival for NHBDD kidneys. The combination of basiliximab, CsA and MMF resulted in a graft survival rate of 98% at one and 2 years.

Age and duration related changes in muscle sympathetic nerve activity in Parkinson's disease

OBJECTIVE

To clarify the characteristics of sympathetic vasomotor function in Parkinson's disease by sympathetic neurographic analysis.

METHODS

Muscle sympathetic nerve activity (MSNA) was recorded using a microneurographic technique at rest and during head up tilt in 18 patients with idiopathic Parkinson's disease and 21 healthy controls.

RESULTS

Heart rate and blood pressure at rest did not differ between index and control subjects. The increase in these variables and MSNA in response to tilting was slightly blunted in the Parkinson's group. Resting MSNA showed a negative correlation with age in patients with Parkinson's disease (p<0.05) and a positive correlation with age in controls (p<0.01). There was a negative correlation between duration of disease or disability levels and MSNA (p<0.01).

CONCLUSIONS

Sympathetic vasomotor function may be related to age and disease duration in Parkinson's disease.

Clinical study on the antiseptic effect of povidone-iodine solution for the surgical field of digestive tract operations

Our previous study showed 10% povidone-iodine solution (Isodine) to be safe and effective for skin antisepsis in healthy young adults. The present study was carried out in 45 adult and old-age patients undergoing surgery (average age 62 years). 10% povidone-iodine solution was effective for skin antisepsis; however, after completion of the intra-abdominal procedures, contaminations were found due to the type II and IV operations with unprotected incision sites and wound walls. Diabetes was found to be one of the most important factors in surgical site infection. In conclusion, the antiseptic efficacy immediately after application of 10% povidone-iodine solution was evidenced in surgical patients with class II wounds. The solution was also effective for the prevention of postoperative skin wound infection.

Ipsilateral thalamic MRI abnormality in an epilepsy patient

In a 19-year-old patient with status epilepticus arising in the right parietal neocortex, unenhanced ictal MRI showed abnormalities mainly in the right cerebral cortex, contralateral cerebellum, and ipsilateral thalamus. The thalamus is considered a key site of functional abnormality in this patient.

UV-irradiation-induced DNA immobilization and functional utilization of DNA on nonwoven cellulose fabric

Immobilization of double-stranded DNA onto nonwoven cellulose fabric by UV irradiation and utilization of DNA-immobilized cloth were examined. The immobilized DNA was found to be stable in water, with the maximum amount of fabric-immobilized DNA being approximately 20 mg/g of nonwoven fabric. The DNA-immobilized cloth could effectively accumulate endocrine disruptors and harmful DNA intercalating pollutants, such as dibenzo-p-dioxin, dibenzofuran, biphenyl, benzo[a]pyrene and ethidium bromide. Additionally, DNA-immobilized cloth was found to bind metal ions, such as Ag+, Cu2+, and Zn2+. The maximum amounts of bound Ag+, Cu2+, and Zn2+ onto DNA-immobilized cloth (1 g) were approximately 5, 2, and 1 mg, respectively. DNA-immobilized cloth containing Ag+ showed antibacterial activity against Escherichia coli and Staphylococcus aureus. DNA-immobilized cloth without metal ion and with Cu2+ or Zn2+ did not show antibacterial activity. These results suggest that immobilized DNA imparts useful functionality to cloth. DNA-immobilized cloth prepared by UV irradiation has potential to serve as a useful biomaterial for medical, engineering, and environmental application.

Oxygenation reactions of various tricyclic fused aromatic compounds using Escherichia coli and Streptomyces lividans transformants carrying several arene dioxygenase genes

Bioconversion (biotransformation) experiments on arenes (aromatic compounds), including various tricyclic fused aromatic compounds such as fluorene, dibenzofuran, dibenzothiophene, carbazole, acridene, and phenanthridine, were done using the cells of Escherichia coli transformants expressing several arene dioxygenase genes. E. coli carrying the phenanthrene dioxygenase (phdABCD) genes derived from the marine bacterium Nocardioides sp. strain KP7 converted all of these tricyclic aromatic compounds, while E. coli carrying the Pseudomonas putida F1 toluene dioxygenase (todC1C2BA) genes or the P. pseudoalcaligenes KF707 biphenyl dioxygenase (bphA1A2A3A4) genes was not able to convert these substrates. Surprisingly, E. coli carrying hybrid dioxygenase (todC1::bphA2A3A4) genes with a subunit substitution between the toluene and biphenyl dioxygenases was able to convert fluorene, dibenzofuran, and dibenzothiophene. The cells of a Streptomyces lividans transformant carrying the phenanthrene dioxygenase genes were also evaluated for bioconversion of various tricyclic fused aromatic compounds. The ability of this actinomycete in their conversion was similar to that of E. coli carrying the corresponding genes. Products converted from the aromatic compounds with these recombinant bacterial cells were purified by column chromatography on silica gel, and identified by their MS and 1H and 13C NMR analyses. Several products, e.g., 4-hydroxyfluorene converted from fluorene, and cis-1,2-dihydroxy-1,2-dihydrophenanthridine, cis-9,10-dihydroxy-9,10-dihydrophenanthridine, and 10-hydroxyphenanthridine, which were converted from phenanthridine, were novel compounds.

OK432-induced killer cell activity: potential method for monitoring immunological complications after renal transplantation

BACKGROUND

Various clinical and biochemical parameters are currently in use for monitoring allograft rejection. However, the mechanism of allograft rejection is complex and it is frequently difficult to obtain a prompt and accurate diagnosis. We examined the usefulness of OK432-induced killer cell activity as an immunological monitoring system for acute renal rejection after renal transplantation.

METHODS

Twenty-four renal transplant recipients, seven patients on haemodialysis, and 10 normal volunteers were enrolled in our study. The killer cell activity of peripheral blood mononuclear cells was induced by culturing these cells with the immunopotentiator, OK432, a heat and penicillin-treated lyophilized powder of the Su-strain of Streptococcus pyogenes.

RESULTS

The OK432-induced killer cell activity of renal transplant recipients without acute rejection (stable recipients) was significantly lower than in normal volunteers. In four renal transplant recipients with acute rejection, the killer cell activity was significantly higher than in stable recipients. In three recipients suffering from opportunistic infections, killer cell activity was significantly suppressed compared with stable recipients.

CONCLUSIONS

Our new test utilizing OK432-induced killer cell activity is potentially useful for monitoring the immunological state and complications after renal transplantation.

[A case of Guillain-Barré syndrome after Campylobacter jejuni enterocolitis: anti-ganglioside antibody levels with or without Guillain-Barré syndrome]

A 38-year old man developed enterocolitis one day after he had ingested raw chicken. Nine days later, his grip strength weakened. Eleven days later, he was admitted to our hospital with weakness of four limbs, dysphagia and dysarthria. Serum anti-Campylobacter jejuni antibody and anti-ganglioside antibodies (GM1, GD1a, GD1b, GalNAc-GD1a) were positive, and motor action potentials were not evoked at all extremities. He was diagnosed as having Guillain-Barré syndrome. After receiving immune absorption therapy and plasma exchange therapy, the patient improved. Another person who had also consumed the same raw chicken developed colitis only. Five weeks later, the anti-GalNAc-GD1a-IgG antibody titers (O.D. 490 nm) of the patient and the other man who developed colitis were 0.324 and 0.118, respectively. It was suggested that the pathogenesis of Guillain-Barré syndrome after Campylobacter jejuni enterocolitis may be related to the type and titer of anti-ganglioside antibodies and also to the sensitivity of the individual.

Influence of anesthesia on brain distribution of [(11)C]methamphetamine in monkeys in positron emission tomography (PET) study

We investigated the influence of anesthesia on the brain distribution of [11C]methamphetamine (MAP) obtained by the positron emission tomography (PET) using the normal rhesus monkeys. We clarified that the brain uptake of [11C]MAP under halothane anesthesia was faster and higher than that under pentobarbital. The difference of the effect of anesthesia is an important problem in pharmacokinetic study in PET with experimental animals.

Biotransformation of phenanthrene and 1-methoxynaphthalene with Streptomyces lividans cells expressing a marine bacterial phenanthrene dioxygenase gene cluster

The phdABCD gene cluster in a marine bacterium Nocardioides sp. strain KP7 codes for the multicomponent enzyme phenanthrene dioxygenase. phdA encoding an iron-sulfur protein large subunit alpha, phdB encoding its small subunit beta, phdC encoding ferredoxin, and phdD encoding ferredoxin reductase, were replaced in such a way that the termination codons of the preceding open reading frames were overlapped with the initiation codons of the following genes. This manipulated phdABCD gene cluster was positioned downstream of the thiostrepton-inducible promoter PtipA in a high-copy-number vector pIJ6021, and introduced into the gram-positive, soil-inhabiting, filamentous bacterium Streptomyces lividans. The recombinant S. lividans cells converted phenanthrene into a cis-diol form, which was determined to be cis-3,4-dihydroxy-3,4-dihydrophenanthrene by its UV spectral data as well as HPLC property, using the authentic sample for comparison. This biotransformation proceeded very efficiently; 200 microM and 2 mm of phenanthrene were almost completely converted to its cis-diol form in 6 h and 32 h, respectively. In addition, the S. lividans cells carrying the phdABCD gene cluster were found to transform 1-methoxynaphthalene to two products, which were identified to be 8-methoxy-2-naphthol in addition to 8-methoxy-1,2-dihydro-1,2-naphthalenediol by their EI-MS, 1H- and 13C-NMR spectral data.

[Long-term experience with renal transplantation in systemic amyloidosis: a case report]

Renal transplantation was performed on a 39-year old woman with secondary amyloidosis due to rheumatoid arthritis. She remains alive and renal function has been maintained satistfactorily with the exception of proteinuria ten years after transplantation. Recent renal biopsy showed no amyloid recurrence, but the presence of chronic rejection reaction and mild cyclosporin arteriolopathy. Symptoms related to systemic amyloidosis and rheumatoid arthritis improved after transplantation. Renal transplantation is the recommended therapy for the type AA systemic amyloidosis. This is the second report of long-term experience with renal transplantation in systemic amyloidosis in Japan.

Transient renal tubular acidosis in a neonate following transplacental acetazolamide

Renal tubular acidosis (RTA) was observed in a preterm boy shortly after birth. His mother had glaucoma and had been treated during pregnancy with oral acetazolamide, a carbonic anhydrase inhibitor. When RTA developed, acetazolamide was detected in his serum demonstrating transplacental acetazolamide passage.

Solution structure of micelle-bound H5 peptide (427-452): a primary structure corresponding to the pore forming region of the voltage dependent potassium channel

A 26-mer peptide with the sequence of the pore forming region (residues 427-452) of the Shaker K(+) channel (H5 region) was chemically synthesized. Analyses by CD and two-dimensional 1H NMR spectroscopy were used to investigate the structure of the peptide bound to SDS micelles in solution, which are commonly used in biophysical studies. The tertiary structure of the peptide as a monomer was composed of an alpha-helix (431-438), a turn (439-442), and random coils (427-430, 443-452), and was very similar to that of the pore forming region of the native K(+) channel from Streptomyces lividans determined by X-ray analysis. This result suggests that even an isolated peptide forms a native-like conformation for residues from 431 to 442, depending on its intrinsic amino acid sequence and the surrounding environment.

Usefulness of redox tolerance test in evaluating fatty liver

BACKGROUND/AIMS

In living-related liver transplantation, fatty liver should be exactly detected in the healthy donor with noninvasive measurement before the surgery. The study aimed to investigate the usefulness of redox tolerance test in diagnosing fatty liver.

METHODOLOGY

The subjects were 32 patients who underwent an abdominal surgery. They did not show any abnormal values in biochemical evaluations, nor had they diabetes. Under informed consent, liver specimens were obtained intraoperatively, and the subjects were divided into three groups according to the degree of hepatic fatty deposit: group A has fatty deposits at less than 10% of hepatocytes (n = 12), group B showed the deposits at 10-30% (n = 10), group C has the deposits of more than 30% (n = 10). Before the surgery, redox tolerance test was performed as follows; arterial blood samples were obtained successively at 75 g oral glucose load over a 120-min period, and the arterial ketone body ratio and blood glucose level were determined. The ratio of increased arterial ketone body ratio (AKBR) to increased blood glucose (BG) level (100 x delta AKBR/delta BG) was calculated as redox tolerance index.

RESULTS

After fasting state, arterial ketone body ratio and blood glucose level did not differ among the three groups. However, the values of redox tolerance index in groups B (0.73 +/- 0.08) and C (0.46 +/- 0.04) were significantly lower than those in group A (1.85 +/- 0.31).

CONCLUSIONS

The redox tolerance test was exceedingly sensitive indicator for objectively diagnosing the fatty liver.

Isolation and Structure Elucidation of Vicenistatin M, and Importance of the Vicenisamine Aminosugar for Exerting Cytotoxicity of Vicenistatin

A new analogue of vicenistatin was isolated from the producing strain Streptomyces sp. HC-34. A characteristic of the elucidated structure involved the existence of a neutral sugar mycarose instead of an aminosugar vicenisamine of vicenistatin. The absolute stereochemistry of the new analogue (named as vicenistatin M) was determined by the synthesis of D-mycarose and of vicenistatin M itself. Biological testing of vicenistatin M suggested the importance of vicenisamine for exerting the cytotoxicity of vicenistatin.

Detection of congenital malaria by polymerase-chain-reaction methodology in Dar es Salaam, Tanzania

The examination of congenital malaria was performed by Giemsa staining and polymerase-chain-reaction (PCR) methodology. We randomly selected 298 neonates who had been admitted to Muhimbili Medical Center (MMC) at Dar es Salaam, Tanzania. One baby among all the enrolled neonates was recognized as having a congenital malaria infection, which gave a prevalence of 0.33%. The present result was 5-fold the clinically recognized prevalence of congenital infection with malaria in the ward. The PCR method identified two cases, one of which was negative as determined by the Giemsa-staining method. Therefore, the PCR method was useful for the detection of scant amounts of malarial parasites in numerous blood samples. The screening of malaria by a sensitive PCR method contributes to reduce the mortality of asymptotic neonates in particular.