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Biomedical subjects

H Ishikawa

Publications and source records attributed to H Ishikawa.

At least 19 recordsLinked to original sources

Identification of novel adhesion proteins in mouse peritoneal macrophages.

When mouse peritoneal macrophages were made to adhere firmly on glass surface and then removed by sequential treatment with hypotonic triethanolamine and Nonidet P-40, a set of proteins were found to be left behind at the sites of adherent cells. Such glass-adherent proteins were detected as round or ellipsoidal patches of autofluorescence under a confocal laser microscope, and visualized ultrastructurally as aggregates of narrow threads of unique loop structures which were composed of linearly aligned particles of 22 +/- 2 nm in diameter. Lithium dodecylsulfate-polyacrylamide gel electrophoresis of the glass-adherent proteins showed two major bands, 12 kDa and 14 kDa, which always co-existed in any different sample. The polyclonal antibody raised against these two proteins specifically stained the glass-adherent proteins in situ. The adhesion of macrophages to glass was significantly blocked with Fab fragments of the antibody. The in situ cross-linking experiment suggested that these two proteins might be closely associated with each other to form complexes. Hence, these proteins can be reasonably considered to be responsible for non-specific adhesion of macrophages to glass.

Animals

Structures of chaperonins from an intracellular symbiont and their functional expression in Escherichia coli groE mutants.

An intracellular symbiont harbored by the aphid bacteriocyte, a specialized fat body cell, synthesizes in vivo substantially only one protein, symbionin, which is a member of the chaperonin-60 family of molecular chaperones. Nucleotide sequence determination of the symbionin region of the endosymbiont genome revealed that it contains the two-cistron operon sym. Just like the Escherichia coli groE operon, the sym operon was dually led by a heat shock and an ordinary promoter sequence. According to the nucleotide sequence, symbionin was 85.5% identical to GroEL of E. coli at the amino acid sequence level. SymS, another protein encoded in the sym operon, which is a member of chaperonin-10, was 79.6% identical to GroES. Complementation experiments with E. coli groE mutants showed that the chaperonin-10 and chaperonin-60 genes from the endosymbiont are expressed in E. coli and that they can function as molecular chaperones together with endogenous GroEL and GroES, respectively.

Amino Acid Sequence

Galanin-induced alteration of electrolyte transport in the rat intestine.

Effects of rat and porcine galanin on rat intestinal ion transport were examined in vitro. In the rat distal colon, a sustained increase in short-circuit current (Isc) was produced by the serosal addition of rat galanin at a concentration as low as 10(-9) M, and a maximal increment was observed at 10(-7) M. Porcine galanin was approximately 100 times less potent than rat galanin. In the rat jejunum, rat galanin produced only a slight and transient decrease in basal Isc. The response to rat galanin was not influenced by atropine, hexamethonium, or amiloride, but was virtually abolished by tetrodotoxin or furosemide. Rat galanin did not significantly influence the increase in Isc elicited by electrical field stimulation in the rat colon and jejunum. Transmural unidirectional 22Na and 36Cl fluxes in the rat colonic mucosa were measured under short-circuited conditions, and rat galanin significantly decreased net sodium and net chloride absorption. These findings suggest that galanin acts as a secretory modulator in the rat colon via noncholinergic neural transmission.

Amiloride

Monoclonal antibodies recognising pol and env proteins of mammalian retroviruses.

Mouse monoclonal antibodies were generated for three 20- to 23-mer synthetic peptides whose amino acid sequences were highly conserved in the pol or env regions of 14 mammalian and two avian retroviruses. By Western-blot analysis, these antibodies recognised the epitopes in major and minor pol or env proteins of six mammalian type-C and -D retroviruses. One of the anti-env monoclonal antibodies was found to recognise all the env transmembrane proteins of six mammalian retroviruses examined.

Amino Acid Sequence

Kimura's disease with marked proliferation of HLA-DR+CD4+ T cells in the skin, lymph node and peripheral blood.

A 41-year-old female had atopic dermatitis-like skin lesions since the age of 21, and for the past 6 years many skin tumors developed on the body, lower extremities and other areas. The histological picture of the tumor, eosinophilia and high IgE in the peripheral blood were consistent with a diagnosis of Kimura's disease. Although the tumors were markedly reduced by oral prednisolone administration, thereafter papules appeared disseminated over the body with swelling of superficial lymph nodes. Immunohistochemical examination indicated marked proliferation of HLA-DR+CD4+ T cells in the skin and lymph nodes, and two-color flow cytometry confirmed it in the lymph nodes and peripheral blood.

Adult

Studies on antiulcer drugs. VI. 4-Furyl-2-guanidinothiazoles and related compounds as potent histamine H2-receptor antagonists.

A series of 4-furyl-2-guanidinothiazole derivatives and related compounds were synthesized and evaluated for histamine H2-receptor antagonist and gastric acid antisecretory activities. Among them, compounds I-17, I-48 and I-49 showed high activities in these tests. In addition, compound I-17 possessed potent inhibitory activities on each of the gastric ulcers induced by stress, ethanol and HCl-aspirin. On the other hand, compound I-48 demonstrated antimicrobial activity against Helicobacter Pylori and the potency was far stronger than that of clinically used H2-antagonists. Some structure-activity relationships are discussed.

Animals

Anti-hypotensive effects of M6434, an orally active alpha 1-adrenoceptor agonist, in rats.

The anti-hypotensive effects of M6434 were evaluated and compared with those of other orally active sympathomimetics in rats. Oral administration of M6434 (0.5-2.0 mg/kg) and midodrine (1.0-5.0 mg/kg) also produced a dose-related increase in mean arterial pressure in normotensive rats. The pressor effect of M6434 was about 4 times more potent than that of midodrine. Both M6434 and midodrine caused a dose-dependent decrease in heart rate. The pressor effect of M6434 (1.0 mg/kg) did not diminish after its repeated administration for 7 days. The pretreatment with M6434 (0.5-1.0 mg/kg) and midodrine (2.0-5.0 mg/kg) improved the orthostatic index in the experimental model of postural hypotension in rats. The effect of M6434 on postural hypotension was about 5 times more potent than that of midodrine. Intravenously injected M6434 (3-300 micrograms/kg) produced a dose-dependent increase in the blood pressure of pithed rats. These results suggest that M6434 possesses a potent antihypotensive activity which is superior to that of midodrine, and M6434 may be useful in the treatment of essential and postural hypotension.

Administration, Oral

Possible involvement of nuclear oncoproteins in regulation of DNA replication.

Polyomavirus DNA replication requires its enhancer which contains an AP-1 site. We have shown that protooncogenes, c-jun and c-fos, whose products form heterodimeric transcription activator, AP-1, strongly stimulate polyomavirus DNA replication through the AP-1 site. The mechanisms by which this enhancer stimulates replication and transcription are different. By replacing the enhancer with the oligonucleotides representing the binding site of a transcription factor of interest, any transcription factor with the known binding sequence can be characterized in this replication assay. When Rel protein was examined, we were able to reveal a new domain in v-Rel protein which can stimulate replication strongly. Whether this domain also coincides with transforming potential of v-Rel protein is currently under investigation.

Animals

Common factors contributing to intractable pain and medical problems with insufficient drug uptake in areas to be treated, and their pathogenesis and treatment: Part I. Combined use of medication with acupuncture, (+) Qi gong energy-stored material, soft laser or electrical stimulation.

Most frequently encountered causes of intractable pain and intractable medical problems, including headache, post-herpetic neuralgia, tinnitus with hearing difficulty, brachial essential hypertension, cephalic hypertension and hypotension, arrhythmia, stroke, osteo-arthritis, Minamata disease, Alzheimer's disease and neuromuscular problems, such as Amyotrophic Lateral Sclerosis, and cancer are often found to be due to co-existence of 1) viral or bacterial infection, 2) localized microcirculatory disturbances, 3) localized deposits of heavy metals, such as lead or mercury, in affected areas of the body, 4) with or without additional harmful environmental electro-magnetic or electric fields from household electrical devices in close vicinity, which create microcirculatory disturbances and reduced acetylcholine. The main reason why medications known to be effective prove ineffective with intractable medical problems, the authors found, is that even effective medications often cannot reach these affected areas in sufficient therapeutic doses, even though the medications can reach the normal parts of the body and result in side effects when doses are excessive. These conditions are often difficult to treat or may be considered incurable in both Western and Oriental medicine. As solutions to these problems, the authors found some of the following methods can improve circulation and selectively enhance drug uptake: 1) Acupuncture, 2) Low pulse repetition rate electrical stimulation (1-2 pulses/second), 3) (+) Qi Gong energy, 4) Soft lasers using Ga-As diode laser or He-Ne gas laser, 5) Certain electro-magnetic fields or rapidly changing or moving electric or magnetic fields, 6) Heat or moxibustion, 7) Individually selected Calcium Channel Blockers, 8) Individually selected Oriental herb medicines known to reduce or eliminate circulatory disturbances. Each method has advantages and limitations and therefore the individually optimal method has to be selected. Applications of (+) Qi Gong energy stored paper or cloth every 4 hours, along with effective medications, were often found to be effective, as Qigongnized materials can often be used repeatedly, as long as they are not exposed to rapidly changing electric, magnetic or electro-magnetic fields. Application of (+) Qi Gong energy-stored paper or cloth, soft laser or changing electric field for 30-60 seconds on the area above the medulla oblongata, vertebral arteries or endocrine representation area at the tail of pancreas reduced or eliminated microcirculatory disturbances and enhanced drug uptake.(ABSTRACT TRUNCATED AT 400 WORDS)

Acupuncture Therapy

Bi-directional transmission of molecular information by photon or electron beams passing in the close vicinity of specific molecules, and its clinical and basic research applications: 1) Diagnosis of humans or animal patients without any direct contact; 2) Light microscopic and electron microscopic localization of neuro-transmitters, heavy metals, Oncogen C-fos (AB2), etc. of intracellular fine structures of normal and abnormal single cells using light or electro-microscopic indirect Bi-Digital O-Ring Test.

In 1985, Omura, Y. discovered that, when specific molecules were placed anywhere in the close vicinity of the path of a light beam (laser), their molecular information, as well as information on electrical & magnetic fields, is transmitted bi-directionally along the path of this light beam. Namely, this information is transmitted in the direction the light beam is projected and towards the direction from which the light beam is coming. This finding was applied to the following clinical and basic research: 1) In the past, using indirect Bi-Digital O-Ring Test, human or animal patients were diagnosed through an intermediate third person holding a good electrical conducting probe, the tip of which was touching the part of the patient to be examined. However, in order to diagnose the patient in isolation from a distance, or a dangerous or unmanagable unanesthesized animal, such as a lion or tiger, the author succeeded in making a diagnosis by replacing the metal conducting probe with a soft laser beam which is held by the one hand of the third person whose index finger is placed in close vicinity of the laser beam generated by a battery-powered penlight-type solid state laser generator. Thus, diagnosis within visible distance, without direct patient contact, became a reality. 2) Using a projection light microscope, by giving indirect Bi-Digital O-Ring Test while contacting with a fine electro-conductive probe on the magnified fine structure of normal and abnormal cells, various normal and abnormal intracellular substances were localized through a third person holding a pure reference control substance with the same hand that is holding the probe as an intermediary for the indirect Bi-Digital O-Ring Test. Instead of the photon beam in a light microscope, the author found that, using an electron beam passing through the close vicinity of specific molecules of specimens in an electron microscope, the molecular information is transmitted to the magnified fluorescent screen, and an indirect Bi-Digital O-Ring Test could be performed through a projected penlight-type solid state soft laser beam on the magnified intracellular structure through an observation glass window. Using the magnified fine structure of the cells, by either a light projection microscopic field or electron microscope, in various cancer cells of both humans and animals, Oncogen C-fos (AB2) and mercury were found inside of the nucleus. Integrin alpha 5 beta 1 was found on cell membranes and nuclear cell membranes of cancer cells. Acetylcholine was not found anywhere within cancer cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

[Small cell carcinoma of the bladder. Small cell lung cancer-associated ganglioside (Fuc GM1) expression].

A 61-year-old male visited us with chief complaints of macroscopic hematuria and bladder irritation symptoms. Cystoscope, U/S, MRI, and CT showed an extensive non-papillary, wide-based tumor centering around the anterior wall of the bladder. Transabdominal U/S-guided full-thickness biopsy indicated a pT3a (Biopsy) primary small cell carcinoma of the bladder containing neuroendocrine granules. Immunohistochemical studies revealed Fuc GM1, an antigen related to small cell carcinoma of the lung. Neoadjuvant therapy consisted of preoperative irradiation at 50 Gy and intra-arterial infusion chemotherapy with CDDP and THP. Since a follow-up full thickness biopsy indicated pT0 (Biopsy), total cystectomy was performed. Examination of the resected specimen also indicated pathological CR.

Carcinoma, Small Cell

[A case of primary intracranial malignant melanoma showing leptomeningeal dissemination].

A 28-year-old woman was hospitalized in drowsy state with signs of increased intracranial pressure. CT scans revealed diffuse increased density with marked enhancement in the subarachnoid space, as well as ventricular dilatation. V-P shunt operation was performed to control intracranial pressure. Repeated cytological examinations of CSF couldn't determine the tumor origin. CT scan of thoracic spine showed a cystic tumor in its dorsal aspect. T2-weighted MRI revealed multiple spotty low intensity, specific to melanin granules, throughout the whole spine. Her thoracic spine was explored, and the intradural tumor was partially removed. Histopathological examination revealed the tumor cell which had dark nucleus with conspicuous nucleolus and cytoplasmic granules. These findings were compatible with malignant melanoma. Her general condition were deteriorated progressively and she died about 5 months after her admission. Postmortum examination showed diffuse leptomeningeal invasion of dark tumor throughout the entire central nervous system, and metastasis to peritoneum and omentum via V-P shunt system. Histopathological examination proved the tumor to be malignant melanoma. Electrone microscopic examination also revealed melanosome in the cytoplasm. Primary intracranial malignant melanoma is divided in two groups, nodular type and leptomeningeal type. In the latter type, early diagnosis is very difficult, just as in our case, because only a little tissue specimen can be obtained. In a case of leptomenigeal carcinomatosis, possibility of primary malignant melanoma, though rare, should always be kept in mind, and specific staining such as Fontana-Masson's staining should be tried.

Adult

False positive reaction of heat-inactivated sera in enzyme-linked immunosorbent assay for antibody to hepatitis C virus.

Specimens were heated at 56 degrees C or 62 degrees C to analyze the mechanisms of false positive reactions in the Ortho enzyme-linked immunosorbent assay (ELISA) for the detection of antibody to hepatitis C virus (HCV). The highest correlation was obtained between the difference in HCV antibody titer of 56 degrees C-heated and native sera and IgG concentration. Monoclonal IgG gammopathy sera developed marked increases in the titer by preheating. However, slight increases after preheating were observed in monoclonal IgA gammopathy sera. Similar increases in the titer by preheating were also demonstrated in immunoglobulin products containing IgG. Direct bindings of denatured IgG with C100-3 and 5-1-1 antigens were shown in recombinant immunoblot assay (RIBA). These results could show the participation of denatured IgG in the false positive reaction in Ortho-HCV-ELISA. Caution is necessary in evaluating the anti-HCV antibody titers of heat-inactivated sera.

Enzyme-Linked Immunosorbent Assay

Mutations induced by DNA lesions in hot spots of the c-Ha-ras gene.

In order to investigate whether several DNA lesions (O6-methylguanine, 8-hydroxyguanine, xanthine, an abasic site analogue and hypoxanthine) activate a c-Ha-ras gene and to determine the type of mutations induced by the DNA lesions, they were introduced into a synthetic c-Ha-ras gene by DNA cassette mutagenesis techniques. The modified genes were transfected into mouse NIH3T3 cells and the c-Ha-ras genes present in transformed cells were analysed. O6-methylguanine and xanthine induced a mutation to A, hypoxanthine induced a mutation to G. 8-hydroxyguanine and the abasic site analogue caused random mutations in the modified and adjacent positions. These results indicated that the synthetic c-Ha-ras gene is very useful for the detection of mutations caused by a DNA lesion.

3T3 Cells

Effect of manidipine, a novel calcium channel blocker, on quality of life in hypertensive patients.

A multicenter open study was performed to evaluate manidipine monotherapy for 6 months on quality of life in hypertensive patients. One hundred and sixty-six patients with essential hypertension were enrolled. Of these, 2 were excluded because of violation of entry criteria, 4 withdrew from treatment because of side effects, and 12 for personal reasons. Manidipine treatment observed at a daily dose of 10 to 20 mg produced effective reduction in blood pressure during the course of the study. Adverse reactions such as palpitation or headache were experienced by 5 of 166 (3%) patients. Quality of life (QOL), assessed grossly by attending physicians, was rated as improved in 62% and unchanged in 36% of patients. Significant improvements in mean QOL scores were noted in general symptoms, physical symptoms and general well-being, work performance and satisfaction, sleep scale, emotional state, cognitive function, sexual function, and self-control. Elderly patients, age 60 years and older, achieved significant improvement in the same QOL items as in all cases; there was no difference between younger and older age groups. In conclusion, manidipine monotherapy is useful for treating patients, including the elderly, with essential hypertension, and this therapy improves their quality of life.

Adult

Structures and activity of angiotensin-converting enzyme inhibitors in an alpha-zein hydrolysate.

Peptides that inhibit angiotensin-converting enzyme (ACE) were isolated from alpha-zein hydrolysate prepared with thermolysin. Their chemical structures were identified by Edman degradation and fast-atom bombardment mass spectrometry. Most of them were found to be tripeptides such as Leu-Arg-Pro, Leu-Ser-Pro, and Leu-Gln-Pro, having IC50 values of 0.27, 1.7, and 1.9 microM, respectively. These peptides were synthesized by a solid phase procedure and had similar ACE inhibitory activities as the isolated inhibitors. The hypotensive activity of Leu-Arg-Pro on spontaneously hypertensive rats was also investigated, with the result that the the blood pressure decreased by 15 mmHg after a 30 mg/kg intravenous injection.

Amino Acid Sequence

Further study on the 1,4-alpha-transglucosylation of rubusoside, a sweet steviol-bisglucoside from Rubus suavissimus.

Rubusoside (the beta-D-glucosyl ester of 13-O-beta-D-glucosyl-steviol), which is the major sweet principle of leaves of Rubus suavissimus S. Lee, was subjected to 1,4-alpha-transglucosylation by the cyclodextringlucanotransferase-starch system (the CGTase system). The tri- and tetra-glucosylated products were isolated together with the mono- and di-glucosylated products, which had already been isolated. A prominent increase in intensity of the sweetness was observed for the compounds which were di- and tri-glucosylated at the 13-O-glucosyl moiety. This result further substantiated the structure-sweetness relationship for 1,4-alpha-glucosylated compounds of steviol-glycosides reported previously. For protection of the 19-COO-glucosyl moiety against glucosylation by the CGTase system, the 4-hydroxyl group of the 19-COO-glucosyl moiety was beta-galactosylated by the beta-galactosidase-lactose system. This galactosylated compound was subjected to a regio-selective glucosylation of the 13-O-glucosyl moiety by the CGTase system, which was followed by enzymic elimination of the galactosyl group to furnish an exclusive preparation of the improved sweeteners just mentioned.

Carbohydrate Sequence