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H Mochida

Publications and source records attributed to H Mochida.

29 records · Page 2Linked to original sources

[New sex pheromone isolated from the abdominal glands of male newt, Cynops pyrrhogaster].

Sodefrin, a novel decapeptide which attracts female newts, Cynops pyrrhogaster was isolated from the abdominal gland of the male of the same species. Synthetic sodefrin was tested for its activity with sexually active females and males and sexually inert females. It attracted only sexually active females. The effect of sodefrin was blocked by a bilateral nostril plugging with cotton balls soaked in melted vaseline. Immunoelectronmicroscopic study using antiserum against sodefrin revealed that sodefrin was located mainly in the secretory granules in the epithelial cells of the abdominal gland of the cloaca.

Abdomen↗

Dimethyl sulfoxide (DMSO) is mutagenic for bacterial mutagenicity tester strains.

We used the Ames method with the modification of pre-incubation to evaluate the potential mutagenicity of DMSO. We performed the assays using nine different Ames Salmonella strains and Escherichia coli strains WP2 and WP2uvrA. DMSO was found to be mutagenic for Salmonella typhimurium TA1537 and TA2637 (the latter strain being isogenic to TA1537 but carrying plasmid pKM101) and for E. coli WP2uvrA. The mutagenic activity of DMSO observed at a concentration of 33% was about 10 times higher than the background level (65 revertants induced) for TA1537 after 20 min of incubation, where some lethal toxicity was observed. The mutagenicity of DMSO was observed in the presence and absence of rat liver S9 mix.

Animals↗

Amino acids suppress intracellular protein degradation in rat liver during parenteral nutrition.

The effects of variations in the amino acid supply on the rates of synthesis and degradation of liver proteins and on the rate of synthesis and secretion of plasma proteins were investigated. Rats were nourished by infusion of total parenteral nutrition solutions containing four different levels (0, 1.65, 3.3 and 6.6%) of amino acids for 7 d. The fractional rate of total protein synthesis in the liver was determined by injecting a flooding dose of [3H]phenylalanine. The proportion of newly synthesized proteins retained and exported by the liver was estimated by injecting a tracer dose of [14C]leucine and then measuring the protein radioactivity remaining in the liver and present in the plasma after secretion was completed. The rate of plasma albumin synthesis was significantly lower in the 0 and 1.65% amino acid groups than in the other groups. The fractional synthesis rates of liver domestic proteins, however, were essentially the same in rats administered all levels of amino acids except for the 0% amino acid group, which showed a slightly higher value than the other groups. The fractional degradation rates of liver domestic proteins, calculated as the difference between the fractional synthesis rate of liver domestic proteins and the net gain of liver proteins, were found to be inversely related (r = -0.999, P < 0.05) to the level of amino acids in infusion solutions up to 3.3% amino acids. It was concluded that protein degradation plays the predominant role in the regulation of liver protein mass.

Amino Acids↗

Pro-opiomelanocortin-containing neurons in rat median eminence.

A significant number of pro-opiomelanocortin (POMC)-containing cells were detected in the rat median eminence (ME) by immunocytochemistry using an antibody raised against a synthetic peptide corresponding to the cleavage site between adrenocorticotropin and beta-lipotropin moieties. Distribution of POMC-positive cells was restricted to the internal zone of the anterior parts of the ME. Such cells were observed as early as the 14th day of gestation in the area of the primitive ME, long before glial fibrillary acidic protein-positive cells appeared postnatally in this structure. Dissociated cell cultures obtained from the ME of 1-day-old rats produced cells immunoreactive for neurofilaments and the POMC moiety. Such cells displayed a neuronal morphology: the cell body was oval (13-18 microns) with long and fine beaded fibers. These findings clearly demonstrate the early appearance of POMC neurons in the developmental ME, a target organ of the hypothalamic infundibular neurons.

Aging↗

[Subclavian artery to internal carotid artery bypass with saphenous vein graft in the treatment of bilateral common carotid artery occlusion; a case report].

A case of left common carotid artery occlusion, which was treated by a saphenous vein graft, is reported. A 49-year-old right handed male was admitted to the hospital because of right hemiparesis and aphasia. These symptoms disappeared spontaneously two weeks after admission. However, visual acuity remained impaired on the left side due to occlusion of the central retinal artery. Angiography revealed complete occlusion of the common carotid arteries as well as patency of the internal carotid arteries on both sides. PET and 123I-IMP-SPECT studies showed hypoperfusion in the left cerebral hemisphere. To restore the blood flow as well as to remove the source of the emboli, endarterectomy was performed on the left internal carotid artery. This was followed by a saphenous vein graft between the left subclavian and the internal carotid artery. Postoperative angiography revealed patency of the bypass, and a SPECT study revealed increased blood flow in the left cerebral hemisphere. The patient has remained in stable condition during the following 30 months with no neurological problems. We conclude that in the treatment of complete occlusion of the common carotid artery and subsequent cerebral hypoperfusion, a bypass graft between the internal carotid and the subclavian artery is quite effective, and that the site of the bypass graft should carefully be sought for by using preoperative angiographic studies.

Anastomosis, Surgical↗

[Palinopsia caused by tentorial meningioma. Case report].

Palinopsia is defined as persistence or recurrence of a visual image when the stimulus is no longer present. The authors describe a female patient with a left tentorial meningioma who experienced recurrent visual images. Computed tomography revealed a well demarcated, high-density mass above the left side of the tentorium, but formal field testing revealed no visual field defect. The findings in this case suggest that the palinopsia may have been the result of disordered temporal synthesis of visual experiences.

Female↗

Therapeutic effects of a new, anti-allergic ophthalmic preparation.

A 0.1% Ketotifen ophthalmic preparation was evaluated in 11 cases of conjunctivitis due to Japanese cedar pollinoisis (three cases also associated with vernal catarrh). The following results were obtained concerning the safety and the therapeutic efficacy of the preparation. (1) In the computation of the overall effects of the preparation, a marked therapeutic effect was noted in three out of 11 cases studied while one case remained unaffected. The overall effective rate was computed to be 91%. (2) The time required for the preparation to take effect was found to be 3 days or less in seven cases (70.0%) out of 10 in which therapeutic effects were noted. (3) In observations of the adverse effects of the preparation, transient irritation at the site of application was noted in seven cases. No other serious side effects were recorded. From the above results, it was concluded that the present preparation is an effective therapeutic agent for conjunctivitis caused by pollinosis.

Animals↗

Mutagenicity of N-acylglycinohydroxamic acids and related compounds.

The mutagenic activity of twenty-nine new N-acylglycinohydroxamic acids and related compounds was tested on Bacillus subtilis (Rec(+), Rec(-)) and Salmonella typhimurium (TA 98, TA 100). All the N-(substituted-benzoyl)glycinohydroxamic acids, except 3-acetylaminobenzoyl-derivative, were shown to be mutagenic to both test bacteria, whereas most of the N-aliphatic acylglycinohydroxamic acids were found to be non-mutagenic. In the present study, we discussed out observations focussing on the structure-activity correlation between their chemical structures and mutagenic activities.

Bacillus subtilis↗

Mutagenicity and cytotoxicity of naphthoquinones for Ames Salmonella tester strains.

The molecular mechanisms involved in quinone cytotoxicity, especially mutagenicity, are still largely unknown. In order to better understand the molecular aspects of the mechanisms of quinone mutagenicity and cytotoxicity, we examined them by using a series of 13 simple structural naphthoquinone (NQ) derivatives for 9 Ames Salmonella mutagenicity tester strains in the presence of absence of liver homogenate S9 mix from rats induced with phenobarbital and 5,6-benzoflavone. Most NQs used in this study showed mutagenicity with and/or without S9 mix. The most potent mutagenic NQ was 2,3-dichloro-1,4-NQ, with mutagenicity of 18 induced revertants/nmol/plate for strain TA104 without S9 mix. Among the strains used, TA104, which is sensitive to oxidative mutagens, was the most sensitive to the NQs, and the second most sensitive strain was TA2637, which detects bulky DNA adducts. The relationship of mutagenic potency to the one-electron reduction potential with TA104 suggested that the higher redox potential NQs were more mutagenic than the lower redox potential NQs. Significant reduction of the mutagenicity of 1,4-naphthoquinone without S9 mix was observed in the presence of catalase. Enhancement of the mutagenic potential of the NQs by the pKM101 plasmid implicated in error-prone repair was also observed. The most cytotoxic NQ was 2,3-dichloro-5,8-dihydroxy-1,4-NQ, and the least cytotoxic NQ was beta-NQ-4-sulfonic acid potassium salt, a 700-fold range in potency. The cytotoxic effect of the NQs was largely dependent on the structures of their substituents.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗