Search PubMed⌕ Search

Biomedical subjects

S Murakami

Publications and source records attributed to S Murakami.

At least 847 records · Page 47Linked to original sources
PubMed1983

Continuous axillary brachial plexus block.

Continuous axillary brachial plexus block was performed in 597 patients undergoing prolonged operations on the hand. The technique required placement of a 5 cm 23 gauge teflon intravenous catheter in the axillary perivascular sheath. Lidocaine 1.5 per cent or mepivicaine 1.5 per cent (20-40 ml) were used for the initial block dose. Surgery was completed in 77.2 per cent of patients (460) with the axillary block alone while in 19.1 per cent of patients (114) supplementary narcotic administration or additional regional blocks were required. In 3.7 per cent of patients (22) the technique was considered a complete failure. Complications included local anaesthetic toxic reactions (2.85 per cent, 17 cases), nerve injury (0.50 per cent, three cases) and one case of major haematoma formation. The advantages of this technique and the possible complications are discussed.

Adult↗
PubMed1983

Central projection of nuchal group I muscle afferent fibers of the cat.

To investigate the central projection of nuchal group I afferent fibers of nerves which supply the complexus (COM), biventer cervicis (BV), splenius (SP), and occipitoscapularis (OCC) muscles, experiments were conducted on cats anesthetized with chloralose-urethane. A total of 246 neurons was found to respond to electrical stimulation of those nerves. Of these neurons, 99.2% were located in the ipsilateral external cuneate nucleus (ECN) and 0.8% in the ipsilateral main cuneate nucleus. Ninety-seven neurons responded only to the BIV, 88 neurons only to the SP, and 56 neurons to the OCC alone. The number of monosynaptically activated neurons from group I fibers were found to be 26 in 97 neurons which responded to the BIV, 20 in 88 neurons responded to the SP, and 8 in 56 neurons which responded to the OCC. The ECN contains these neurons organized in a somatotopic manner. Neurons from distal muscle (the OCC) project to medial parts and from proximal muscle (the BIV) to more lateral parts of the nucleus. Forty-three of the 143 neurons in the ECN (30.1%) were activated antidromically to electrical stimulation of the ipsilateral inferior peduncle and anterior lobules IV and V of the cerebellum. Thalamic responses from nuchal muscle afferent fibers were recorded in a very narrow region of nucleus ventralis posterolateralis (VPL) which is situated dorsolaterally to the forelimb muscle afferent (deep radial nerve) projection area. The cortical evoked potentials from these nerve stimulations were observed in the anterior suprasylvian gyrus, areas 2 or 5, which we regarded as a transitional area between the second somatosensory and association areas, and the postcruciate dimple (PCD) or area 3a. Cortical potentials in the PCD were reduced after lesion of the VPL, where the focal potentials evoked by nuchal muscle afferent stimulation were recorded.

Afferent Pathways↗
PubMed1983

Keratin in human lung tumors. Patterns of localization of different-molecular-weight keratin proteins.

In this immunohistochemical study, antiserums to different molecular weight keratin proteins (45kd, 46kd, 55kd, and 63kd) were utilized to determine the profiles of keratin proteins present in a variety of pulmonary neoplasms. Different histologic types of lung carcinoma exhibited different patterns of keratin staining. Squamous cell carcinomas stained strongly for 45K, 46K, and 55K keratin, with staining for 63K restricted to areas or individual cells with cytoplasmic keratinization. Adenocarcinomas showed variable, generally weak staining for 45K, 46K, and 55K keratin and were uniformly negative for 63K keratin both in frozen and paraffin sections. Mesotheliomas and reactive mesothelial cells, by contrast, stained positively for 63K keratin in addition to keratins of lower molecular weights. Differences in staining for 63K keratin between mesothelioma and adenocarcinoma may have diagnostic application. Moreover, individual cytokeratins may serve as markers of tumor differentiation and provide information as to the origin of neoplastic cells.

Adenocarcinoma↗
PubMed1982

Cell cycle inhibition of yeast spheroplasts.

Osmotically stabilized yeast spheroplasts are capable of extensive DNA synthesis. Although the rate of DNA synthesis in spheroplasts is approximately one-third that of intact cells, the relative amounts of nuclear and mitochondrial DNA synthesized by spheroplasts is very similar to the relative amounts synthesized by intact cells. Furthermore, nuclear but not mitochondrial DNA synthesis is inhibited in MATa spheroplasts by the application of the yeast mating pheromone, alpha-factor. Similarly, DNA synthesis is reversibly temperature-sensitive in spheroplasts created from cdc7 and cdc8 mutant cells.

Cell Cycle↗
PubMed1982

Saccharomyces cerevisiae spheroplasts are sensitive to the action of diphtheria toxin.

Diphtheria toxin kills spheroplasts of Saccharomyces cerevisiae but not the intact yeast cells. After 2 h of exposure to ca. 10(-7) M toxin, less than 1% of spheroplasts were able to regenerate into intact cells. The same high levels of toxin inhibited the rate of protein synthesis by more than 90% within 1 h, whereas RNA and DNA synthesis were not inhibited until 4 h or exposure. Both killing and protein synthesis inhibition were dependent on toxin concentration. The nature of the toxin-cell interaction was also studied by using fragments of intact toxin and mutant toxin proteins. Neither toxin fragment A nor CRM45 nor CRM197 affected spheroplasts, but CRM197 and ATP prevented the inhibitory action of intact toxin. These results suggest that toxin acts on S. cerevisiae spheroplasts in much the same manner as it acts on sensitive mammalian cells.

Cell Division↗
PubMed1982

Serum gastrin and motilin in treated and untreated hyperthyroidism.

To study the gastrointestinal hormones in hyperthyroidism and the interrelations with the thyroid hormones, the preprandial serum gastrin and motilin were measured by radioimmunoassay in 104 patients before and after the treatments. The following results were obtained: 1) Serum gastrin concentration in hyperthyroidism was significantly higher than that of the control, and when the patients reached euthyroidism or hypothyroidism after the treatments, the gastrin concentrations in the serum decreased to the normal level. There was a positive correlation between the thyroid hormones and the serum gastrin. 2) Serum motilin concentration in hyperthyroidism was slightly lower than that of the control. As the patients reached the euthyroid or hypothyroid state after the treatments, an increasing tendency of motilin was observed, though the change was not significant. There was a slightly negative correlation in gastrin versus motilin and also in T4 versus motilin.

Adult↗