Transformation of fibroblasts into endothelial cells during angiogenesis

Light- and electron-microscopic autoradiography have been used to study fibroblast transformation into endothelial cells in the formation of new blood vessels during wound healing in rabbit ear chambers. When cultured fibroblasts labeled with tritium thymidine were transplanted autologously into the chambers, newly formed blood vessels contained endothelial cells labeled with tritium thymidine. This result suggests that fibroblasts play a pivotal role in angiogenesis, as progenitors of endothelial cells in newly formed blood vessels.

Inhibition of K+ channels by chlorpromazine in rat ventricular myocytes

Isolated rat ventricular myocytes were investigated with the whole-cell patch-clamp technique. Chlorpromazine inhibited inward-rectifying K+ currents (IC50 = 6.1 microM), time-independent outward currents (IC50 = 16 microM) and transient outward K+ currents. In the latter case, 100 microM of chlorpromazine reduced the amplitude of the peak current recorded at a clamp potential of 50 mV from 2.14 +/- 0.59 nA to 1.38 +/- 0.20 nA (n = 4) and decreased the time course of fast inactivation from 8.29 +/- 1.17 msec to 4.01 +/- 0.90 msec (n = 4). In addition, chlorpromazine blocked the ATP-dependent K+ current, which was activated either by the channel opener rilmakalim (10 microM) or by metabolic inhibition with carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP, 500 nM; IC50 for rilmakalim = 2.5 microM; IC50 for FCCP = 11.5 microM). The drug caused marked depolarization of the resting potential at higher concentrations (50 microM) from -79 +/- 3 mV to -27 +/- 11 mV (n = 4). The reversibility from channel block was slow and only partial for time-independent currents, especially inward-rectifying K+ currents, but it was relatively fast and complete for time-independent currents. Thus chlorpromazine blocks a variety of K+ channels in heart muscle cells. Inasmuch as the potency of inhibition is less than the previously reported use-dependent block of Na+ channels, the cardiovascular adverse effects of chlorpromazine are probably caused mainly by the latter effect.

Facile methods for isolation and determination of gangliosides in a small scale: age-related changes of gangliosides in mouse brain synaptic plasma membranes

A quantitative isolation method for gangliosides from small sizes of samples has been developed. Total lipids were separated into gangliosides and other lipids using Phenyl Sepharose column chromatography. Gangliosides were recovered in a yield of 99%. Determination of gangliosides was performed by gas chromatography--mass spectrometry using a selected ion-monitoring technique. These combined methods can provide quantitative isolation and determination of gangliosides from as little as 10 mg fresh brain tissues or 0.5 mg protein of membrane fractions. The present methods were successfully applied to the analysis of gangliosides from mouse brain synaptic plasma membranes to reveal that the ganglioside contents and composition remain constant from adult to senescence.

Visual abnormalities and occipital EEG discharges: risk factors for West syndrome

Seventeen infants (7 boys and 10 girls) with visual abnormalities (such as poor tracking and following and nystagmoid eye movement) and occipital slow activities with irregular polyspikes on EEG were studied. Two thirds of the children showed development of West syndrome with hypsarrhythmia on follow-up EEG. In 1 child, hypsarrhythmia was evident on the follow-up EEG, but no clinical seizures occurred. Because most of the children in our series developed West syndrome, patients with visual abnormalities associated with occipital EEG discharges in early infancy may be at high risk for West syndrome. Occipital abnormalities in early infancy may relate to the occurrence of West syndrome.

N-acetylgalactosaminyl GD1a is a target molecule for serum antibody in Guillain-Barré syndrome

Serum antibodies against such major glycolipids as GM1, GD1b, and LM1 have been reported in patients in the acute phase of Guillain-Barré syndrome (GBS). Because minor unidentified glycolipids also may be targets of antibodies in GBS sera, we assayed serum antibody against a crude ganglioside fraction using thin-layer chromatogram immunostaining. Antibody activity was detected against a band that migrated just below GD1a in 6 of the 50 patients with GBS tested. Antibody titer, as determined by enzyme-linked immunosorbent assay, decreased during the course of the disease. All 6 patients had suffered gastrointestinal infection before the neurological onset of GBS and showed low amplitudes for the compound muscle action potentials and normal or only slightly decreased nerve conduction velocities. Thin-layer chromatogram immunostaining did not show this antibody activity in any of the 16 normal and 119 disease controls. The unidentified glycolipid was isolated by DEAE-Sephadex A-25 column chromatography, sialidase treatment, and Iatrobeads column chromatography. Fast atom bombardment-mass spectra showed it to be N-acetyl-galactosaminyl GD1a.

[Juvenile Parkinson's disease initially presenting as bulbar incoordination: a case report]

We report a case of juvenile Parkinson's disease which initially presented as bulbar incoordination at the age 12. The condition was characterized by dystonia of the upper extremities. The patient was a 14-year-old female. The patient's main symptoms were bulbar dysfunction. Resting and action tremor, akinesia, stooped posture, distortion of the trunk, dystonia of the upper extremities, oculogyric crisis, and impairment of the postural reflex were seen. The bulbar symptoms were considered to be attributable to circumoral uncoordination. Although L-dopa decarboxylase inhibitors were markedly effective in alleviating these symptoms, an adverse reaction due to the agent was observed as the form of oral dyskinesia. Since the changes in blood concentration of L-dopa after administration of the agent was clearly reflected in the surface electromyogram, we concluded that this diagnostic procedure is useful in evaluating the therapeutic efficacy of L-dopa.

Improved oral absorption of enteric coprecipitates of a poorly soluble drug

An anticancer agent, N-[[[4-(5-bromo-2-pyrimidinyloxy)-3-chlorophenyl]amino]carbonyl]-2 - nitrobenzamide (HO-221, 1), shows poor oral absorption and is only slightly soluble in water (0.055 microgram/mL at 37 degrees C). The coprecipitates with polyvinylpyrrolidone or a vinylpyrrolidone and vinylacetate copolymer (copolyvidone) showed a marked increase of the dissolution rate and attainment of temporary supersaturation of 1. The oral bioavailability of these preparations in dogs at a dose of 1 of 5 mg/kg was approximately 60%, which was 3.5 times greater than that of a micronized preparation. Further, the enteric coprecipitate with hydroxypropyl methylcellulose phthalate 200731, which showed a dissolution profile similar to that of the copolyvidone preparation at pH 6.5 but no dissolution at pH 1.2, revealed the almost complete oral absorption. Because intraduodenal administration of the copolyvidone coprecipitate showed a higher absorption than that of per oral administration, it was suggested that the partial precipitation of crystallites in the nonenteric coprecipitates occurred before reaching the absorption site, the small intestine.

Antitumor effects of IST-622, a novel synthetic derivative of chartreusin, against murine and human tumor lines following oral administration

The antitumor effects of 6-O-(3-ethoxypropionyl)-3',4'-O-exo- benzylidenechartreusin (IST-622), a new synthetic derivative of chartreusin (CT), were investigated. Following oral administration, IST-622 showed marked antitumor effects against various mouse tumors such as P388 and L1210 leukemias, B16 melanoma, Lewis lung carcinoma, Colon 26 and Colon 38 adenocarcinomas, and M5076 reticulum-cell sarcoma. The best antitumor effects were obtained by five intermittent treatments given every 4 days. In addition, IST-622 showed a significant growth-inhibitory effect against two human tumor xenografts, a large-cell lung cancer (Lu-116) and a gastric adenocarcinoma (St-4), among the seven lines tested. IST-622, which was rapidly metabolized into 3',4'-O-exo-benzylidenechartreusin (A-132) and not into CT in vivo or in culture medium, exhibited remarkable growth-inhibitory activity against P388 leukemia in vitro, its 50% growth-inhibitory concentration (IC50) being over 20-fold lower than that of CT. IST-622 showed an in vivo antitumor effect superior to that of authentic A-132, possibly resulting from a higher absorption ratio of IST-622 through the gastrointestinal tract. IST-622 is now under clinical phase I study in Japan.

A novel ganglioside with a free amino group in bovine brain

A novel ganglioside which binds cholera-toxin B-subunit was purified from bovine brain by an h.p.l.c. system using an Aquasil column subsequent to Q-Sepharose column chromatography. T.l.c./immunostaining showed that the isolated ganglioside had about 60% of the binding reactivity of the authentic ganglioside GM1 for cholera-toxin B-subunit. On h.p.l.c., this ganglioside migrated between ganglioside GD1a and GD1b, and was found to give positive reactions with ninhydrin and fluorescamine reagents which specifically react with amino groups. The presence of a free amino group was further confirmed by chemical re-N-acetylation. The N-acetylated product had an identical RF value on h.p.l.c. and similar reactivity with cholera-toxin B-subunit as the authentic GM1. H.p.t.l.c., t.l.c./immunostaining, negative-ion fast-atom-bombardment (f.a.b.)-m.s., and 1H-n.m.r. spectroscopy of the novel ganglioside unequivocally demonstrated that it has the basal structure of GM1 with de-N-acetylated neuraminic acid instead of N-acetylneuraminic acid. In the present study we report for the first time that a ganglioside derivative containing de-N-acetylated neuraminic acid, de-N-acetylated GM1, exists in natural brain tissues.

Novel lacto-ganglio type gangliosides with GM2-epitope in bovine brain which react with IgM from a patient of the amyotrophic lateral sclerosis-like disorder

A motor neuron disorder resembling that of amyotrophic lateral sclerosis was found in a patient who had received the intramuscular administration of a mixture of bovine brain gangliosides (Yuki, N., Sato, S., Miyatake, T., Sugiyama, K., Katagiri, T., and Sasaki, H. (1991) Lancet 337, 1109-1110). A very high titer of anti-GM2 IgM was detected in the patient's serum and the patient quickly recovered after plasmapheresis. The clinical course of the patient appeared to be different from amyotrophic lateral sclerosis and the anti-GM2 IgM was thought to be the culprit. The IgM reacted with GM2, GM1b-GalNAc, SPG(alpha 2-3)-GalNAc, and GD1a-GalNAc, but not with GA2 or GD2, meaning that the epitope recognized by the IgM was the GM2-like terminal structure, GalNAc beta 1-4(Neu-Ac alpha 2-3)Gal beta 1-. In this study, we found two novel GM2-epitope containing gangliosides, X1 and X2, in bovine brain gangliosides by TLC immunostaining using the patient's IgM. They were characterized as unique lacto-ganglio type gangliosides containing the following branching structures. [formula: see text] Their unusual structures may be immunogenic to humans to induce anti-GM2 antibody.

A new O-acetylated trisialoganglioside, 9-O-acetyl GT2, in cod brain

An O-acetylated trisialoganglioside that is converted to GT2 on mild base treatment was found in cod brain. This alkali-labile ganglioside was isolated using high-performance liquid chromatography, and its chemical structure was characterized. This novel ganglioside was identified as a GT2 derivative having an acetyl group at the C-9 position of the external sialic acid. Its chemical structure is as follows.

Isolation and characterization of a trisialyllactosylceramide, GT3, containing an O-acetylated sialic acid in cod fish brain

An O-acetylated ganglioside that generated a trisialyllactosylceramide or GT3 by base treatment was found for the first time in cod fish brain. This ganglioside was isolated by high-performance liquid chromatography, and characterized by fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy in addition to chemical analysis. The structure was identified as a modified GT3 in which the external sialic acid is O-acetylated at the C-9 position. The chemical structure is as follows: II3(9-O-Ac-NeuAc2-8NeuAc2-8NeuAc2-3)Lac Cer.

Differential fatty acid release from CA1 and CA3 regions of rat hippocampal slices under hypoxia and hypoglycemia

Rat hippocampal slices were subjected to hypoxia and/or hypoglycemia for 10 min, and free fatty acids released in CA1 and CA3 regions were separately analyzed. Fatty acid accumulation in CA1 was not so significant under hypoglycemia, but very prominent under hypoxia. Free fatty acid levels in CA3 were much less than those in CA1 even under hypoxia plus hypoglycemia. This observation seems to be consistent with the selective vulnerability of CA1 neurons seen in in vivo ischemia. The decreasing order of accumulation of free fatty acid species in CA1 was C16:0 > C18:0 > C18:1 > C20:4 > C22:6. The increment fold as compared to control level was decreasing as follows: C22:6, 28 times; C20:4, 13 times, C18:1, 10 times; C18:0 = C16:0, 3 times. The present experimental conditions using hippocampal slices provided a good in vitro model to prove the selective hypoxic damages of the CA1 subfield in terms of free fatty acid release in association with the membrane degradation.

Glomerulonephritis with various crystalline deposits

A 60-year-old Japanese male was admitted with nephrotic syndrome complaining of facial and pedal edema. Renal biopsy revealed mesangial and endocapillary proliferation with massive mesangial and subendothelial deposits. Deposits of IgA, IgG, IgM, C3 and fibrinogen were identified by immunofluorescence technique in both mesangial and subendothelial areas. Deposits of kappa and lambda light chains were also recognized in similar patterns. Electron microscopy revealed crystalline structures of various appearance in these deposits. A large deposit consisted of various small triangular, quadrilateral and polygonal shapes of deposits with crystalline structures. These crystalline structures exhibited lattice or parallel lamellar lines with different periodic distances. Although a disease producing paraproteinemia was suspected, no immunoglobulin disorder or light chain abnormality could be detected on clinical and laboratory examinations. On the second biopsy, a faint reaction for cryoglobulin was recognized. However, the crystalline deposits observed in this case were absolutely different from the tubular structures seen in cryoglobulinemic nephropathy. This was a very rare and unclassified case.

A review of patients with a 'normal' coronary angiogram over a 3-year period

Over a period of 36 months, we detected 54 patients with normal coronary arteries or non-critical coronary artery stenosis within our study series of coronary angiography. We studied these patients to determine their clinical, electrocardiographic, stress testing and angiocardiographic characteristics. We detected among them a preponderance of female sex and a higher incidence of ethnic Indians. The majority of the patients studied had one or more coronary risk factors. 52% had a normal resting ECG. In those with a positive stress test and reports available for review, there is a near equal distribution of horizontal and J-type ST depression. Those patients with a positive treadmill tend to have a higher left ventricular end diastolic pressure (LVEDP) at cardiac catheterization. We also noted in this group of patients a higher proportion with a small distal left anterior descending artery. These patients also tend to have higher LVEDP even in the presence of normal left ventriculogram. Our current series suggests the possibility of raised left ventricular end-diastolic pressure and the presence of a "small distal left anterior descending artery" syndrome in association with patients with a 'false positive' treadmill test.

Characterization of two novel pyruvylated glycosphingolipids containing 2'-aminoethylphosphoryl(-->6)-galactose from the nervous system of Aplysia kurodai

Two novel acidic glycosphingolipids containing pyruvylated galactose were purified from the nervous tissue of Aplysia kurodai by successive Iatrobeads column chromatographies. By component analysis, sugar analysis, permethylation studies, fast atom bombardment-mass spectrometry, and proton magnetic resonance spectrometry, the structures of these acidic glycosphingolipids, named F-9 and FGL-I, were determined to be: [3,4-O-(S-1-carboxyethylidene)]Gal beta 1-->3 GalNAc alpha 1-->3[6'-O-(2-aminoethylphosphonyl)Gal alpha 1-->2] (2-aminoethylphosphoryl 1-->6)Gal beta 1-->4Glc beta 1-->1ceramide and [3,4-O-(S-1-carboxyethylidene)] Gal beta 1-->3GalNAc alpha 1-->3(Fuc alpha 1-->2)(2-aminoethylphosphonyl-->6 Gal beta 1-->4Glc beta 1-->1ceramide, octadeca-4-sphingenine and anteisononadeca-4-sphingenine. Thus, pyruvylated glycosphingolipids containing phosphoethanolamine in addition to or in place of 2-aminoethylphosphonate are present in the nervous system of Aplysia.

Cytotoxicity of activated platelets to autologous red blood cells

Gel-filtered human platelets exerted lytic activity on autologous red blood cells (RBC) when they were coincubated at 37 degrees C with platelet-activating agents, such as thrombin, collagen, ADP, LPS or PMA in the absence of plasma. Lysis of activated platelets themselves did not occur during the incubation period examined. Morphological observations showed that RBC exposed to thrombin-activated platelets were fragmented and/or transformed into spherocytes. This haemolytic reaction by thrombin-activated platelets did not occur at 4 degrees C, or in the presence of agents which inhibited glycolysis or elevated intracellular levels of cAMP, indicating that energy-dependent and cAMP-regulated platelet metabolism was required for this reaction. When platelets and RBC were incubated in the same vessel, but were prevented from coming into direct cell to cell contact by means of a membrane barrier, their cytotoxicity was reduced but not eliminated completely. No cytotoxic activity against RBC was detected in platelet-free supernatants obtained by centrifugation after activation of platelets with thrombin. On the contrary, activated and washed platelets retained the activity. These observations suggested that the cytotoxic activity was carried by some diffusible and easily inactivated factors, which were continuously produced and liberated from activated platelets. Cyclo-oxygenase inhibitors inhibited the haemolytic activity of thrombin-activated platelets, suggesting a role for some products of platelet-cyclo-oxygenase pathway in platelet-mediated haemolysis. These results provide the first evidence for a direct role of activated platelets in mediation of RBC-damage in the absence of any plasma factors.

Structural characterization of a novel cholinergic neuron-specific ganglioside in bovine brain

A new ganglioside antigen, termed Chol-1 alpha-b, recognized by cholinergic neuron-specific antibody, Chol-1 alpha, was isolated from bovine brain ganglioside mixture using Q-Sepharose. The yield was approximately 1.3 mg from 5 g of the total ganglioside. The chemical structure was characterized as a novel ganglioside by means of gas-liquid chromatography, a permethylation study, mild acid hydrolysis, thin layer chromatography-enzyme immunostaining, fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The ganglioside has the following unique structure. [formula: see text] When examined by thin layer chromatography immunostaining and enzyme-linked immunosorbant assays, this ganglioside has the most intense immunoreactivity with Chol-1 alpha antibody among bovine brain gangliosides. As combined with our previous results (Hirabayashi, Y., Hyogo, A., Nakao, T., Tsuchiya, K., Suzuki, Y., Matsumoto, M., Kon, K., and Ando, S. (1990) J. Biol. Chem. 265, 8144-8151; Ando, S., Hirabayashi, Y., Kon, K., Inagaki, F., Tate, S., and Whittaker, X. (1992) J. Biochem. (Tokyo), 111, 287-290), the present study indicates the occurrence of a new series of gangliosides containing N-acetylneuraminic acid residue attaching to N-acetylgalactosamine as cholinergic specific antigens.

Human meconium gangliosides. Characterization of a novel I-type ganglioside with the NeuAc alpha 2-6Gal structure

Three monosialogangliosides containing the NeuAc alpha 2-6Gal structure have been detected in human meconium by immunological analysis using a monoclonal antibody, MSG-15, and purified by repeated silica beads column chromatography. One was previously shown to be NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer. The remaining two were characterized by proton NMR, fast atom bombardment mass spectrometry, methylation analysis by gas chromatography-mass spectrometry, and immunological studies, and their structures were concluded to be as follows. [formula: see text] The second ganglioside has the same structure that was isolated from bovine buttermilk (Takamizawa, K., Iwamori, M., Mutai, M., and Nagai, Y. (1986) J. Biol. Chem. 261, 5625-5630), and this is the first description of the occurrence of the ganglioside with the branched structure with two N-acetyllactosamines linked to lactosylceramide via beta 1-6 and beta 1-3 in human linked to lactosylceramide via beta 1-6 and beta 1-3 in human tissues. The third ganglioside is a novel ganglioside with blood group I-type and a NeuAc alpha 2-6Gal structure.

A new antitumor antibiotic product, demethylchartreusin. Isolation and biological activities

A new antitumor antibiotic, 3''-demethylchartreusin was isolated from the culture broth of Streptomyces chartreusis, as a minor component of crude chartreusin. It is structurally related to chartreusin, containing same aglycone of chartreusin, but different sugar moieties. 3''-Demethylchartreusin exhibits some potent inhibitory activities against murine tumors.