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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.

We report two patients with meningoencephalomyelitis without evidence of extra central nervous system (CNS) involvement. Brain MRI showed linear perivascular radial gadolinium enhancement patterns and spinal cord MRI showed longitudinal extensive T2-hyperintensity lesions. Pathological findings from brain biopsies were angiocentric T-cell predominant lymphoid infiltrates that lacked Epstein-Barr virus-positive atypical B cells. The patients were initially suspected to have isolated CNS-lymphomatoid granulomatosis (LYG). Thereafter, glial fibrillary acidic protein (GFAP)-immunoglobulin G were detected in their cerebrospinal fluid. This finding suggested autoimmune GFAP astrocytopathy. We speculate there is a link between isolated CNS-LYG and autoimmune GFAP astrocytopathy., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Pseudoalteromonas sp. strain A25 is a marine bacterium that reveals strong algicidal activity against diatoms. We report the draft genome sequence for this strain, which consists of two contigs (3,887,303 bp and 850,536 bp). Further genomic analysis might facilitate an understanding of the algicidal mechanisms of this strain., (Copyright © 2019 Kitaguchi et al.)

Quantitative chemical analyses of Ni 3 Al based hardening precipitates (γ') in polycrystalline Ni based superalloys have been conducted using energy dispersive X-ray spectroscopy (EDX), coupled with a scanning transmission electron microscope (STEM). The aim of the current investigation is (1) to evaluate the accuracy of calibration (k factor determinations and absorption corrections using a combination of differential X-ray absorption (DXA) and convergent beam electron diffraction (CBED)) by comparing with thermodynamic calculations and (2) to demonstrate the importance of the EDX chemical analysis by taking advantage of its unique capabilities to analyse sub-micron scale chemistries within a mesoscopic field of view under STEM. Our experimental findings show good agreement with the mole fraction ratio of γ' to the disordered γ matrix predicted using the Lever rule on a thermodynamically stabilised unimodal superalloy, RR1000. The significance of analysing a statistically viable number of samples in thermodynamically metastable superalloys and the chemical fluctuations found in coarse γ', sized above 200 nm on a scale of a few hundred nanometres in the context of solving a complex morphological evolution of γ' particles is demonstrated., (Copyright © 2019 Elsevier B.V. All rights reserved.)

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.

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., (© 2017 American Academy of Sleep Medicine)

Cerebral air embolism (CAE) is a rare cause of stroke. Most cerebral air emboli are caused by iatrogenic factors, such as invasive cardiac and pulmonary procedures. Here, we report an unusual case of CAE not related to any medical intervention. An 87-year-old woman became unresponsive after vomiting. A computed tomography (CT) scan of the head 6 hours after the onset of the vomiting revealed multiple air emboli, mainly in the watershed area between the right anterior and middle cerebral arteries. Magnetic resonance imaging with T2* gradient echo showed the air emboli as granular hypointensities. Diffusion-weighted imaging revealed an area of hyperintensity along the cortical region of the right frontal lobe. Head CT scans showed that the size and number of the air emboli rapidly decreased on day 2 and disappeared on day 9. We also performed a chest CT and found pneumomediastinum, which gradually improved over the clinical course. We also found pulmonary fibrosis and bronchiectasis, suggesting an underlying pulmonary vulnerability. In this case, the emesis may have been a trigger for the CAE, which was followed by pneumomediastinum. This case suggests that CAE can occur in a noniatrogenic situation, especially in a patient with pulmonary vulnerability., (Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Carbon quantification and the standardisation in a pure cementite were conducted using pulsed-laser atom probe tomography (APT). The results were analysed to investigate a dependence on three distinct experimental parameters; the laser pulse energy, the cryogenic specimen temperature and the laser pulse frequency. All the measurements returned an apparent carbon content of 25.0±1.0at%. Carbon content measurements showed no clear dependence on the cryogenic temperature or the laser pulse frequency. However, the results did demonstrate a strong correlation with the laser pulse energy. For lower laser pulse energies, the analysis returned carbon contents higher than the stoichiometric ratio. It was suggested that this effect is due to pile up of (56)Fe(++) at the detector and as a consequence there is a systematic preferential loss of these ions throughout the course of the experiment. Conversely, in experiments utilising higher laser pulse energies, it was found that the carbon contents were smaller than the stoichiometric ratio. In these experiments an increasing fraction of the larger carbon molecular ions (e.g., C5 ions) were detected as part of a multiple detection events, which could affect the quantification measurements., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Hepatic arterial infusion (HAI) or systemic chemotherapy has been used to treat unresectable colorectal liver metastases. The prognosis of the disease in recent years has been improved because chemotherapy is performed before hepatectomy to reduce tumor size (conversion therapy). The purpose of this study was to investigate the safety and efficacy of conversion therapy following HAI immunochemotherapy., Methods: Hepatic arterial infusion of 5-fluorouracil (5-FU)/polyethylene glycol (PEG)-IFNα-2a was performed in 21 patients. The primary endpoint was the safety of HAI and hepatectomy. The secondary endpoints were response rate, rate of conversion to hepatectomy, survival rate, and prognostic factors., Results: With regard to side effects, drugs were discontinued temporarily in one patient because of a decrease in white blood cell count; however, other patients continued chemotherapy. The response rate with HAI was 61.9 %, and the conversion rate was 38.1 %. Hepatectomy was completed successfully without mortality. Median progression-free survival (PFS) was 11.5 months (with and without conversion, 16.7 and 4.8 months, respectively; p = 0.021). Median overall survival was 34.6 months (with and without conversion, 48.4 and 26.6 months, respectively; p = 0.003). Prognosis was poor when the number of metastatic tumors was ≥10 [PFS: hazard ratio (HR) 32.21, p = 0.003; overall survival (OS): HR 9.13, p = 0.07], but prognosis improved after hepatectomy (OS: HR 0.08, p = 0.09)., Conclusions: Hepatic arterial infusion immunochemotherapy with 5-FU/PEG-IFNα-2a was performed safely without major side effects. Prognosis is expected to improve after successful conversion to hepatectomy.

We have developed an apparatus to investigate transport critical current (I(c)) as a function of magnetic field and temperature using only liquid nitrogen. The apparatus consists of a (Bi,Pb)(2)Sr(2)Ca(2)Cu(3)O(10) (Bi-2223) superconducting magnet, an outer dewar, and a variable temperature insert (VTI). The magnet, which is operated in depressurized liquid nitrogen, generates magnetic field up to 1.26 T. The sample is also immersed in liquid nitrogen. The pressure in the VTI is controlled from 0.02 to 0.3 MPa, which corresponds to temperature ranging from 66 to 88 K. We have confirmed the long-term stable operation of the Bi-2223 magnet at 1 T. The temperature stability of the sample at high transport current was also demonstrated. The apparatus provides easy-operating I(c) measurement environment for a high-T(c) superconductor up to 500 A in magnetic fields up to 1 T and in temperatures ranging from 66 to 88 K.

A novel trilithium compound, Li(3)[B(C(6)H(4)O(2)){O(CH(2)CH(2)O)(3)CH(3)}(2)][N(SO(2)CF(3))(2)](2) (1-2.0), with solid-state ionic conductivity was synthesized. The crystal structure of 1-2.0 consists of the one-dimensional ionic conduction paths. The paths were afforded as a result of the self-assembled stacking of the component molecules of 1-2.0 with channel structures containing lithium ions. In this supramolecule, one lithium ion holds the component molecules in specific positions to construct a supramolecular structure with thermally stable ionic conduction paths and the others behave as carrier ions exhibiting selective lithium-ion conductivity. Owing to the existence of both roles for the lithium ions, this electrolyte shows selective lithium-ion conductivity., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Spinocerebellar ataxia 36 is caused by the expansion of the intronic GGCCTG hexanucleotide repeat in NOP56. The original article describing this condition demonstrated that patients with spinocerebellar ataxia 36 present with tongue atrophy, a finding that had not been seen in previous types of spinocerebellar ataxias. A total of 2121 patients with clinically diagnosed spinocerebellar ataxia participated in the study. We screened our patient samples for spinocerebellar ataxia 36 using the repeat-primed polymerase chain reaction method and also determined the clinical features of spinocerebellar ataxia 36. Of the ataxia cases examined, 12 were identified as spinocerebellar ataxia 36. Of these, 7 cases (6 families) were autosomal dominant, 4 cases (three families) had a positive family history but were not autosomal dominant, and 1 case was sporadic. The average age of onset was 51.7 years, and disease progression was slow. The main symptoms and signs of disease included ataxia, dysarthria, and hyperreflexia. Approximately half the affected patients demonstrated nystagmus, bulging eyes, and a positive pathological reflex, although dysphagia, tongue atrophy, and hearing loss were rare. Moreover, the observed atrophy of the cerebellum and brain stem was not severe. The patients identified in this study were concentrated in western Japan. The frequency of spinocerebellar ataxia 36 was approximately 1.2% in the autosomal dominant group, and the age of onset for this condition was later in comparison with other spinocerebellar ataxia subtypes., (Copyright © 2012 Movement Disorder Society.)

A 70-year-old Japanese man developed fever, headache, and lumbago, presumably due to an epidural abscess caused by methicillin-resistant Staphylococcus aureus (MRSA) in the L5-S2 region. On the night of admission to our hospital, he showed disorientation to places and abnormal eating behavior, indicating a complication of MRSA meningitis. Cerebrospinal fluid (CSF) examination confirmed this diagnosis. Although he was treated with venous infusion of vancomycin and meropenem, the CSF culture remained positive for MRSA even a week after the treatment, and Gram-positive cocci were also seen in the CSF. An intrathecal injection of vancomycin (10mg/day) was subsequently added, which resulted in absence of the organism on Gram-stained CSF smear and CSF culture a week later. His condition improved without any adverse effects. Vancomycin cannot freely penetrate the blood-brain barrier (BBB); therefore, when administered intravenously, its concentration in the CSF is insufficient. Therefore, intrathecal injection of vancomycin is necessary to achieve the desired bacteriocidal level in the CSF. Thus, intrathecal administration of vancomycin seems a very effective and safe treatment for MRSA meningitis.

The patient was a 55-year-old female who had multiple liver metastases of rectal cancer. This patient underwent hepatic arterial infusion chemotherapy after low anterior resection for rectal cancer. Hepatic arterial infusion was discontinued due to severe diarrhea, and the administration of UFT (300 mg/day) and LV(75 mg/day) was then begun. The carcinoembryonic antigen (CEA) level was normalized immediately after the start of this administration. One year later, liver metastases disappeared on computed tomography (CT) and a complete response (CR) was achieved. No adverse events were noted, and CR was maintained for 2 years. This therapy can serve as one of the chemotherapies for advanced colorectal cancer.

Chronic cerebral ischemia may accelerate clinicopathological changes in Alzheimer's disease. We have examined whether chronic cerebral hypoperfusion accelerates amyloid beta deposition in amyloid protein precursor transgenic (APP-Tg) mouse. At 5, 8, and 11 months of age, C57Bl/6J male mice overexpressing a mutant form of the human APP bearing the both Swedish (K670N/M671L) and the Indiana (V717F) mutations (APPSwInd) and their litterrmates were subjected to either sham operation or bilateral carotid artery stenosis (BCAS) using microcoils with an internal diameter of 0.18 mm (short-period group). One month after the sham operation or BCAS, these animals were examined by immunohistochemistry for glial fibrillary acidic protein, amyloid beta(1-40) (Abeta(1-40)), amyloid beta(1-42) (Abeta(1-42)), as well as Western blotting and filter assay for Abeta. Another batch of the littermates of APPSwInd mice were subjected to either sham operation or BCAS at 3 months and were examined in the same manner after survival for 9 months (long-period group). In the BCAS-treated group, the white matter was rarefied and astroglia was proliferated. Amyloid beta(1-40) immunoreactivity was found in a few axons in the white matter after BCAS, whereas Abeta(1-42) was accumulated in the scattered cortical neurons and the axons at ages of 6 months and thereafter in the short- and long-period groups. In the neuropil, both Abeta(1-40) and Abeta(1-42) were deposited in the sham-operated and BCAS-treated mice at ages of 9 and 12 months. There were no differences between the short-period group at ages of 12 months and the long-period group. Filter assay showed an increase of Abeta fibrils in the extracellular enriched fraction. Taken together, chronic cerebral hypoperfusion increased Abeta fibrils and induced Abeta deposition in the intracellular compartment and, therefore, may accelerate the pathological changes of Alzheimer's disease.

A new titration system for studying protein-ligand interactions has been developed. In this system, the sample solution is circulated in the route formed by an access path in a split superconducting magnet to maintain a constant protein concentration during the titration experiments. A concentration-control procedure for the ligand/protein ratio is devised, and the ligand/protein ratio is well controlled by this apparatus.

When culturing human umbilical vein endothelial cells in a culture medium containing 4% human serum albumin, it was possible to maintain the epithelioid morphology and function for several months without subculturing. When coculturing endothelial cells and labeled monocytes/macrophages (Mo/Phi) that were collected from peripheral blood and allowed to engulf fluorescent latex beads, some Mo/Phi changed their shapes and became epithelioid cells that were indistinguishable from vascular endothelial cells. This transformation started within several hours of coculturing. At 7 days after the start of coculturing, more than half of the labeled cells were identified as endothelial-like cells morphologically. Furthermore, morphologically altered Mo/Phi did not express Mo/Phi-specific antigens, ie, the MHC Class II molecule and CD68, but expressed VE cadherin and vWF, which are specific antigens for endothelial cells, and labeled cells that changed into endothelial-like cells no longer engulfed fluorescent latex beads. This strongly suggests that peripheral blood monocytes differentiate into endothelial-like cells.

Morphological abnormalities of the cortical microvessels have been reported in Alzheimer's disease (AD), but not in Binswanger's disease (BD), a form of vascular dementia. Therefore, we compared the capillary beds in AD and BD brains, using a modified Gallyas silver impregnation method and immunohistochemistry for beta amyloid. Eight autopsied brains with AD and seven with BD were compared with six control brains. The cortical microvessels in AD were frequently narrowed, and torn off, especially in close proximity to the senile plaques. The capillary densities in AD were significantly decreased as compared with the control brains. In contrast, there were no significant changes in the capillary densities and their morphologies in BD brains. Immunohistochemistry for beta amyloid revealed numerous deposits in the vascular wall and perivascular neuropil exclusively in AD brains. Cortical microvascular changes in AD and their absence in BD may indicate a role of beta amyloid for the microvessel pathology in AD.

S100 protein is expressed primarily by astroglia in the brain, and accumulates in and around the ischemic lesions. Arundic acid, a novel astroglia-modulating agent, is neuroprotective in acute cerebral infarction, whereas the protective effects remain unknown during chronic cerebral hypoperfusion. Rats undergoing chronic cerebral hypoperfusion were subjected to a bilateral ligation of the common carotid arteries, and were allowed to survive for 3, 7 and 14 days. The animals received a daily intraperitoneal injection of 5.0, 10.0 or 20.0 mg/kg of arundic acid, or vehicle, for 14 days. Alternatively, other groups of rats received a delayed intraperitoneal injection of 20.0 mg/kg of arundic acid or vehicle, which started from 1, 3 or 7 days after ligation and continued to 14 days. The degree of white matter (WM) lesions and the numerical density of S100 protein-immunoreactive astroglia were estimated. In the WM of rats with vehicle injections, the number of S100 protein-immunoreactive astroglia increased significantly after chronic cerebral hypoperfusion as compared to the sham-operation. A dosage of 10.0 and 20.0 mg/kg of arundic acid suppressed the numerical increase in S100 protein-immunoreactive astroglia and the WM lesions. These pathological changes were suppressed with delayed treatment up to 7 days in terms of astroglial activation, and up to 3 days in terms of the WM lesions. The protective effects of arundic acid against WM lesions were demonstrated in a dose-dependent manner, and even after postischemic treatments. These results suggest the potential usefulness of arundic acid in the treatment of cerebrovascular WM lesions.

Osteoblastic differentiation from human mesenchymal stem cell (hMSCs) is an important step of bone formation. We studied the in vitro induction of hMSCs by using strontium ranelate, a natural trace amount in water, food and human skeleton. The mRNA synthesis of various osteoblast specific genes was assessed by means of reverse transcription polymerase chain reaction (RT-PCR). In the hMSCs culture, strontium ranelate could enhance the induction of hMSCs to differentiate into osteoblasts. Cbfa1 gene was earlier expressed on day 4 of cell culture (the control group, on day 14) and osteonectin on day 11 (control, on day 21). The early Cbfa1 expression indicates that strontium could enhance osteoblastic differentiation. The detection of osteonectin using strontium induction indicates the role of strontium in enhancing bone remodeling, bone structure stabilization of hydroxyapatite molecule and collagen fibril organization. The cultured hMSCs in the presence of strontium expressed genes of bone extracellular matrix: collagen type I, bone sialoprotein and osteocalcin on the same days as control (same medium with no strontium). Concentration of strontium ranelate has been recommended to be optimized in between 0.2107 - 21.07 microg/ml whereas the high concentration up to 210.7 microg/ml have delayed effect on osteoblastic differentiation with delayed expression on Cbfa1 and osteonectin, and inhibitory effect on bone sialoprotein expression. In addition, strontium could help cell expansion by maintaining cell proliferation rate of hMSCs and osteoblast lineage. We recommend that the strontium is an important factor for inducing mesenchymal stem cells to differentiate into osteoblasts with further enhancement on bone formation. This model might provide a useful cell source for tissue engineering and bone repair.

A hydrogen bond formed between the superoxide anion and the ammonium ion (NH4+) accelerates electron transfer from the C60 radical anion to oxygen significantly, whereas the tetra-n-butylammonium ion has no ability to form a hydrogen bond with the superoxidie anion, exhibiting no acceleration of the electron-transfer reduction of oxygen. The second-order rate constant of electron transfer from C60*- to O2 increases linearly with increasing concentration of NH4+. This indicates that O2*- produced in the electron transfer from C60 to O2 is stabilized by 1:1 complex formation between O2*- and NH4+. The 1:1 complex formed between O2*- and NH4+ was detected by ESR. The binding of O2*- with NH4+ results in a positive shift of the reduction potential of O2 with increasing concentration of NH4+, leading to the acceleration of electron transfer from C60*- to O2.

We evaluated the pharmacological profiles of FMS586 [3-(5,6,7,8-tetrahydro-9-isopropyl-carbazol-3-yl)-1-methyl-1-(2-pyridin-4-yl-ethyl)-urea hydrochloride], a novel tetrahydrocarbazole derivative as a neuropeptide Y (NPY) Y5 receptor antagonist. This compound showed a highly selective in vitro affinity for Y5 (IC(50) = 4.3 +/- 0.4 nM) relative to other NPY receptor subtypes like Y1 or Y2. Its binding to Y5 was found to be fully antagonistic from cyclic AMP accumulation assays in human embryonic kidney 293 cells. Pharmacokinetic analysis revealed sufficient oral availability and brain permeability of this compound accompanied with clear dose relation. We attempted to assess the selectivity of FMS586 and, thereby, to infer the physiological role of Y5 in the following feeding experiments in normal rats. An intracerebroventricular injection of NPY and Y5-selective agonist peptide induced acute and robust feeding responses in satiated rats, and prior administration of FMS586 at the doses from 25 to 100 mg/kg clearly inhibited these responses by approximately 55 and 90%, respectively. This compound also showed dose-dependent but transient suppression in natural feeding models of both overnight fasting-induced hyperphagia and spontaneous daily intake. FMS586 did not modulate food intake induced by the topical injection of norepinephrine, galanin, or gamma-aminobutyric acid receptor agonist muscimol to the paraventricular nucleus. In addition, we confirmed the Y5-specific activity profile of FMS586 by immunohistochemical analysis. Taken together, we propose not only that our compound potentially expresses specific blockade of central Y5 signals but also that Y5 receptor would certainly contribute to physiological regulation of food intake in normal rats, as suggested from its origin.

A simple additivity rule holds in the hydrogen transfer reactivity of unsaturated fatty acids with cumylperoxyl radical, which is expressed by the additive contributions of the reactivity of active hydrogens from the 1,4-pentadiene subunit and those of the allylic subunit; the kinetic isotope effect on the hydrogen transfer reactions (KIE = 6.1) is significantly smaller than that observed for lipoxygenase (KIE = 81).

Rate constants of photoinduced electron-transfer oxidation of unsaturated fatty acids with a series of singlet excited states of oxidants in acetonitrile at 298 K were examined and the resulting electron-transfer rate constants (k(et)) were evaluated in light of the free energy relationship of electron transfer to determine the one-electron oxidation potentials (E(ox)) of unsaturated fatty acids and the intrinsic barrier of electron transfer. The k(et) values of linoleic acid with a series of oxidants are the same as the corresponding k(et) values of methyl linoleate, linolenic acid, and arachidonic acid, leading to the same E(ox) value of linoleic acid, methyl linoleate, linolenic acid, and arachidonic acid (1.76 V vs SCE), which is significantly lower than that of oleic acid (2.03 V vs SCE) as indicated by the smaller k(et) values of oleic acid than those of other unsaturated fatty acids. The radical cation of linoleic acid produced in photoinduced electron transfer from linoleic acid to the singlet excited state of 10-methylacridinium ion as well as that of 9,10-dicyanoanthracene was detected by laser flash photolysis experiments. The apparent rate constant of deprotonation of the radical cation of linoleic acid was determined as 8.1 x 10(3) s(-1). In the presence of oxygen, the addition of oxygen to the deprotonated radical produces the peroxyl radical, which has successfully been detected by ESR. No thermal electron transfer or proton-coupled electron transfer has occurred from linoleic acid to a strong one-electron oxidant, Ru(bpy)3(3+) (bpy = 2,2'-bipyridine) or Fe(bpy)3(3+). The present results on the electron-transfer and proton-transfer properties of unsaturated fatty acids provide valuable mechanistic insight into lipoxygenases to clarify the proton-coupled electron-transfer process in the catalytic function.

Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions.

Well-resolved ESR spectra of free pentadienyl radicals have been observed under photoirradiation of di-tert-butylperoxide (Bu(t)OOBu(t)) and polyunsaturated fatty acids in the absence of O(2), allowing us to determine the hfc values. The hfc values of linoleyl radical indicate that the spin density is the largest at the C-11 position. The linoleyl radical is readily trapped by O(2) to produce the peroxyl radical (11-HPO.) in which O(2) is added mainly at the C-11 position of the pentadienyl radical as indicated by the comparison of the ESR spectra of peroxyl radicals derived from linoleic acid and [11,11-(2)H(2)]linoleic acid. The peroxyl radical (13-HPO.), which is initially formed by the hydrogen abstraction from 13-(S)-hydroperoxy-9(Z),11(E)-octadecadienoic acid (13-HPOD) by Bu(t)O., is found to isomerize to 11-HPO. via removal of O(2) from 13-HPO. and addition of O(2) to linoleyl radical to produce 11-HPO. . This finding supports an idea of O(2) entering via a specific protein channel, which determines the stereo- and regiochemistry of the biradical combination between O(2) and linoleyl radical in lipoxygenases.

Electron transfer reduction of p-benzoquinones by cobalt tetraphenylporphyrin is enhanced significantly by the presence of o-bis(phenylcarbamoylmethyl)benzene (o-L) due to the regioselective hydrogen bond formation between the corresponding semiquinone radical anions and o-L, whereas m- and p-isomers (m-L and p-L) have no effect on the electron transfer equilibrium or the rate.

Mice deficient in the Syk tyrosine kinase showed severe petechiae in utero and died shortly after birth. The mechanism of this bleeding, however, remains unknown. Here it is shown that this bleeding is caused by morphologic defects of Syk-deficient endothelial cells during embryogenesis. Immunoblot and reverse transcriptase-polymerase chain reaction Northern blot analysis indicated that Syk is expressed in several endothelial cell lines. Immunocytochemical analysis also confirmed that Syk is expressed in the normal embryonic endothelial cells and is absent in Syk-deficient mice. Furthermore, electron microscopic analysis of Syk-deficient mice revealed an abnormal morphogenesis and a decreased number of endothelial cells. The results indicate a critical role for Syk in endothelial cell function and in maintaining vascular integrity in vivo.

Activation of vascular endothelium is considered as an important facet of inflammation, thrombosis, and vasculitis. Activated endothelial cells express a number of immunologically relevant surface markers which are not detected in dormant condition. These surface markers on endothelial cell may involve in adhesion reaction and migration of blood cell components. We demonstrated increased level of the soluble adhesion molecules in circulating blood of both alpha- and beta-thalassemic patients. These adhesion molecules are theoretically known to be released from endothelial cells. The adhesion molecules included soluble Intercellular Adhesion Molecule-1 (sICAM-1), soluble E-Selectin (ELAM-1), soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), and von Willebrand Factor (vWF). The levels of these adhesion molecules were measured in serum from 32 thalassemic patients and 10 control healthy subjects. As compared to normal, increased sICAM-1 was found in beta-thal/HbE patients with non-splenectomy; BE-NS (p = 0.002), increased ELAM-1 in beta-thal/HbE patients with splenectomy; BE-S (p = 0.01) and HbH with Hb Constant Spring; HbH/CS (p = 0.001), and increased sVCAM-1 in BE-NS; (p = < 0.0001) and BE-S (p = 0.002). Significant increase in von Willebrand Factor (vWF), a marker for endothelial cell, was shown in BE-S (p = 0.04) as compared to normal. Adhesion molecules were also markedly demonstrated in the supernatant of in vitro culture of human vascular endothelial cell in the presence of 30% thalassemic serum, and these adhesion molecules were also detected on the surface of the cells by using the technic of laser scanning confocal microscope and direct immunofluorescence.

With a technic that was developed by us, we found that normal human umbilical vein endothelial cells (HUVEC) in culture characteristically had very little tissue factor (TF) activity either on the surface or in the cells which had been disrupted. In the presence of endotoxin (E. coli O26:B6), a trigger for thrombosis in septicemic patients, we could not detect an increased TF activity of HUVEC on its surface. However, an increase in TF (total TF) was detected after disruption of the cells. The increase in total TF was dose-dependent. Endotoxin at the concentration of 10 micrograms/ml caused around 5 fold increase in total TF activity compared to that of HUVEC in the absence of endotoxin.

Human umbilical vein endothelial cells were cultured in vitro using Iscove's Modified Dulbecco's Medium (IMDM) supplemented with either pooled normal human serum, or pooled thalassemic serum, or autologous umbilical cord serum, or fetal bovine serum. The mitotic activity was determined under the inverted phase contrast microscope and the number of mitotic cells was counted. Our results showed that the mitotic cells decreased in endothelial cell culture with thalassemic serum as compared with normal human serum, autologous umbilical cord serum or fetal bovine serum. The percentage of mitotic cells decreased on day 3 in the presence of beta-thalassemia/HbE serum from both splenectomized and non-splenectomized patients as compared with normal or autologous umbilical cord serum. In the presence of alpha-thalassemic serum, a similar outcome was also observed. From this study we can conclude that the thalassemic sera might contain factors which affect the endothelial cell growth and proliferation by inhibiting mitosis in vitro.

A tetrathionate-decomposing enzyme that catalyzes the decomposition of tetrathionate into thiosulfate and sulfate was purified to homogeneity from tetrathionate-grown Thiobacillus thiooxidans. The enzyme had an apparent molecular weight of 104,000, and was composed of two identical subunits (MW = 58,000) as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme had an isoelectric point at 9.6 and was most active at pH 3.0-3.5 and 40°C. Enzyme activity was increased approximately 100-fold in the presence of 400 mm sulfate ion. The Michaelis constant of this enzyme for tetrathionate in the presence of 20, 50, and 200 mm of sulfate ion was 2.4 mm. Mercuric and ferric ions completely inhibited the enzyme activity at 1 mm. Though cupric ion up to 0.01 mm markedly stimulated the activity in the presence of 20 mm sulfate ion, a higher concentration (1 mm) rather strongly inhibited the activity. Ethylenediaminetetraacetic acid (EDTA) strongly inhibited the activity, but this inhibiton was completely restored by cupric ion.

An increased level of plasma thrombomodulin (TM) in alpha- and beta-thalassaemia was demonstrated using an enzyme-linked immunosorbent assay (ELISA). Nonsplenectomized patients with beta-thalassaemia/haemoglobin E (BE) had higher levels of TM than splenectomized cases (BE-S). Patients with leg ulcers (BE-LU) were found to have the highest increase in TM level. Appearance of larger platelets in all types of thalassaemic blood was observed indicating an increase in the number of younger platelets. These data indicate that injury of vascular endothelial cells is present in thalassaemic patients.

Synthetic peptide analogues of the Arg-Gly-Asp-Ser (RGDS) sequence of fibronectin in which the amino acid of Gly was substituted with another one, named X, i.e. Arg-X-Asp-Ser (R-X-DS), and N-terminal modified R-X-DS have been synthesized to examine their antimetastatic effects in murine lung or liver metastasis models, as well as the inhibitory effect on tumor cell invasion, migration and adhesion in vitro. R-X-DS [X = Leu (L) or D-Leu (1)], as well as RGDS at a high dose of 3000 micrograms, significantly reduced the number of lung tumor colonies when they were co-injected with B16-BL6 melanoma. At a dose of 1000 micrograms/mouse, N-terminal modified R-X-DS, i.e. acetyl-D-R-X-DS [AcDR-X-DS: X = G, L or I], showed a more potent inhibitory effect on the lung or liver metastasis of B16-BL6 melanoma or L5178Y-ML25 lymphoma cells, respectively, as compared with RGDS or R-X-DS. AcDRLDS and AcDRIDS prevented the invasion of B16-BL6 cells into Matrigel/fibronectin- and Matrigel/laminin- coated filters, haptotactic migration, and the adhesion of the cells to both fibronectin- and laminin-coated substrates, whereas AcDRGDS inhibited only fibronectin-mediated cell functions. The intermittent i.v. administration of a water soluble vinylpolymer [poly(carboxyethylmethacrylamide), poly(CEMA)] containing R-X-DS (X = L or 1) or RGDS, following the subcutaneous inoculation of B16-BL6 cells, significantly inhibited spontaneous Jung metastasis as compared with multiple administrations of RGDS, R-X-DS or the untreated control.(ABSTRACT TRUNCATED AT 250 WORDS)

Erythrocytes from 45 patients with thalassemia and/or hemoglobinopathies were studied for their cytoadherence property to the vascular endothelial cells in vitro. In plasma free medium, erythrocytes from patients with beta-thal/Hb E both splenectomized and nonsplenectomized, HbH diseases (alpha-thal 1/alpha-thal 2 and alpha-thal 1/Hb Constant Spring genotypes) and homozygous Hb E subjects bind to endothelial cells at a greater number as compared to the binding cell number of normal erythrocytes (p-value < 0.05 in all types). Addition of autologous platelet-rich plasma or whole blood to the culture system causes further increase in the number of adhering beta-thalassemia red cells. Platelet-rich plasma had more enhancement effect than the whole blood. However, no such enhancement of both platelet-rich plasma and whole blood was demonstrated in the culture of normal or alpha-thalassemia erythrocytes. Increased binding between red cells and endothelial cells may contribute to the greater risk of vascular occlusion in thalassemic patients.

Endothelial cells cultured for 3 days in the presence of hemoglobin H pooled sera had significantly decreased cell proliferation compared to those in normal serum. Inhibition was demonstrated at a concentration of 20% pooled serum in the cultured medium. Further decrease was shown in the presence of 30% pooled hemoglobin H sera. Sera from two genotypes of Hb H disease (alpha-thal 1/alpha-thal 2 and alpha-thal 1/Hb Constant Spring) had the same degree of inhibitory effect. Pooled sera from beta-thal/Hb E patients (both splenectomized or nonsplenectomized cases) had no such inhibitory effect. However, at day 4 and 5, the growth pattern relatively declined. Bilirubin at a concentration greater than 4.0 mg% in the medium 199 also caused significant decrease in cell proliferation. Since the diluted Hb H serum had bilirubin less than 4.0 mg%, the inhibitory effect of the pooled HbH serum is thus not due to effect of bilirubin. The difference between HbH and beta-thal/HbE sera in terms of inhibition of endothelial cell proliferation is the new finding that needs further investigation to explain vascularization and hemostasis in the patients of these two genotypes.

We cultivated endothelial cells of human umbilical vein origin in the presence of red blood cells and platelet-rich plasma, and observed the phenomena which occurred in the petri dish under phase contrast microscopy. Many small particles were observed after an overnight incubation. We washed the dish two times, then added thrombin to the dish. The network of thread-like strands appeared within 10 to 20 minutes of the addition, and at the same time the small particles adhered on the surface of the strands, swelled and fused gradually to cover the surface of the strands completely. Within 30 to 60 minutes the network of the strands changed into a capillary-like structure. These phenomena were not observed if we omitted red blood cells or platelet-rich plasma. Studies by transmission electron microscopy revealed that the inner surface of the lumen of the structure was covered with cells. The cells isolated from the lumen by trypsin grew to confluence in the conventional culture medium, and showed vWF antigen on their surface. These observations indicated that the method described is useful for in vitro study of angiogenesis.

The regioselectivity of six serine proteases for the amino groups of lysine was investigated. alpha-Chymotrypsin showed a preference for the alpha-amino group, although the selectivity can be varied 10-fold depending on the reaction medium. Subtilisin Carlsberg and other bacterial proteases were highly specific for the epsilon-amino group, regardless of the reaction medium: they were used as catalysts for the preparative synthesis of isopeptides in anhydrous tert-amyl alcohol.

Which vasoactive substances that are synthesized in vivo could induce the release of a sufficient amount of prostacyclin (PGI2) to inhibit platelet aggregation from the vascular wall was investigated in the isolated dog heart perfused by a modified method of Langendorff. Infusion of 5 microM bradykinin or 25 u/ml crude thrombin into the heart for 30 sec resulted in the transient appearance of inhibitory activity of platelet aggregation. The inhibitory activity was stable at alkaline pH but unstable at acidic pH and thermolabile. The appearance of the inhibitory activity was prevented by treatment of the coronary vessel with 30 microM indomethacin or 1 mM tranylcypromine. These results indicated that the inhibitory activity was caused by PGI2. When 25 microM acetylcholine, 25 microM noradrenaline, 25 microM isoproterenol, 10 microM adenosine triphosphate (ATP), 5 microM adenosine, 1 microM angiotensin II, 25 microM histamine or 1 microM serotonin was infused for 30 sec, no inhibitory activity of platelet aggregation was observed. Bradykinin (5 X 10(-9) approximately 5 X 10(-6) M) and purified thrombin (1 X 10(-9) approximately 1 X 10(-7) M) induced a dose-dependent release of PGI2 which was assayed using a radioimmunoassay for 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha).