Search PubMed⌕ Search

Biomedical subjects

S Wada

Publications and source records attributed to S Wada.

At least 253 records · Page 14Linked to original sources

[The effectiveness of perfluorotributylamine/pluronic F-68 stem-emulsion (FC43se) against xenograft rejection in the guinea pig-to-rat model].

The administration of perfluorotributylamine/pluronic F-68 stem-emulsion (FC43se), a fluorine compound emulsion, to a rodent discordant xeno-transplantation (dXT) model led to the discovery of the inhibitory effect of this compound against hyperacute rejection (HAR). When a guinea pig heart was transplanted to a rat administered with FC43se (10 microliters/g body weight), rhythmic beating was maintained for 1110 +/- 111.1 min (mean +/- SD; n = 8) whereas the untreated heart continued to beat for 15.5 +/- 6.6 min (mean +/- SD; n = 8). After 720 min of re-beating; pathologic changes observed in the untreated group, such as multiple thrombosis in the coronary vessels, were not observed in the FC43se-administered group by light and electron microscopic examination, and endothelial cells were well preserved. On the other hand, scattered necroses of the myocardium were observed and lymphocytic infiltration was demonstrated in the interstitium. We concluded that FC43se possessed a HAR inhibitory effect by inhibiting thrombus formation in the xeno-graft heart. Using this model, we speculated that action in the vessels of the graft heart (intravascular HAR) caused thrombus formation in the vessels. On the other hand, extravascular HAR causes myocardial necrosis more slowly, not resulting in cardiac arrest in the short term.

Acute Disease↗

Thymosin fraction 5 does not influence urinary tract carcinogenesis by phenacetin and N-butyl-N-(4-hydroxybutyl)nitrosamine in NON/Shi mice.

The effect of thymosin fraction 5 (TF5) on the promotion and progression phases of urinary tract carcinogenesis induced by consecutive administration of phenacetin and N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) in NON/Shi mice was investigated. The study was carried out twice with a minor modification to the protocol in the second experiment. Fifty-seven male NON/Shi mice in experiment 1 and 100 mice in experiment 2 were each divided into four groups. Phenacetin was administered for 8 weeks in experiment 1 and 12 weeks in experiment 2, and subsequently BBN was given for 6 weeks in both cases, for total observation periods of 30 and 34 weeks, respectively. Sixty micrograms of TF5 per mouse was inoculated subcutaneously twice a week during (group 2) or after (group 3) BBN exposure, or both periods (group 4). Group 1 served as a control group without TF5 treatment. Histopathological examination revealed no effects on either induction of urinary tract carcinomas or distant metastasis from renal pelvic carcinomas in either experiment.

Animals↗

Suppressive effects of urine on the SOS responses induced by UV and chemical mutagens.

We studied the antimutagenic effects of urine on the SOS-inducing activity of mutagenic substances by using a novel test system (umu-test) for detecting DNA damaging agents, which uses a new tester strain (Salmonella typhimurium TA1535/pSK1002). The SOS-inducing activity of chemicals was detected in terms of the level of umu operon expression by measuring beta-galactosidase activity. We first examined the effects of various amounts of urine on SOS responses caused by mitomycin C (MMC). As a result, the urine suppressed beta-galactosidase activity of MMC dose-dependently. A urine concentration of 50 microliters/ml in the medium also suppressed 89.9% of SOS response induced by 0.1 microgram/ml of PEP, 75.6% of that induced by 0.02 microgram/ml of AF2 and 60.9% of that induced by 0.1 microgram/ml of AFB1. In addition, a urine concentration of 50 microliters/ml in the medium also suppressed 85.6% of SOS response by 5 J/m2 of UV irradiation. The observed suppression seemed to be directly related to the SOS responses at a cellular level, rather than to interaction between urine and mutagens, because the urine suppressed SOS responses induced not only by various mutagens but also by UV irradiation. These results suggest that urine works as a strong antimutagen against UV and chemical substances.

Antimutagenic Agents↗

Clinical application of paraspinal somatosensory evoked potentials (PS-SEPs) for the diagnosis of spinal cord lesion.

To evaluate the clinical utility of somatosensory evoked potentials elicited by stimulation of the paraspinal region (PS-SEPs), waveform characteristics and scalp topography were studied in 23 normal controls. PS-SEPs were recorded in 22 patients with spinal lesions, and the relation between the abnormal PS-SEPs and clinico-radiological findings was investigated. 1) The normal control study showed clear waveforms on the scalp elicited by stimulation of the paraspinal region from C7 to the L2 spinous process level, with both bilateral and unilateral stimulation. The latency of PS-SEPs was gradually decreased when stimulation was moved in the caudo-rostral direction. 2) The normal range of spinal conduction time and conduction velocity was wide. The conduction velocity resulting from stimulation of the lumbar region tended to be slower than that from stimulation of the thoracic region, perhaps due to the difference in the length of the peripheral cutaneous nerves. 3) There was no correlation between the height and the latency of PS-SEPs. 4) Amplitudes of PS-SEPs after unilateral stimulation of the C7 and Th5 spinous levels were larger on the scalp contralateral to the side of stimulation. These findings were similar to SEPs elicited by median nerve stimulation. There was no significant amplitude laterality of PS-SEPs when the Th10 and L2 spinous levels were stimulated. Posterior tibial nerve SEPs showed a larger amplitude at the scalp ipsilateral to the side of stimulation than at the contralateral side. All these findings suggest that the cortical generator sites of PS-SEPs elicited by C7 and Th5 stimulation are located near the hand area, and those from Th10 and L2 stimulation are between the hand and the foot area. 5) Unilateral stimulation disclosed a clear laterality of sensory disturbance that was obscure when only bilateral stimulation was employed. PS-SEPs showed a high degree of abnormality when the patient had deep sensory disturbance. Generally, abnormal PS-SEPs were found caudal to the clinical sensory level, and a few cases showed abnormal PS-SEPs rostral to the sensory level. The latter might indicate that PS-SEPs detected subclinical sensory disturbance. It was therefore concluded that PS-SEPs are a useful tool for the objective evaluation of sensory disturbance, especially in cases of thoracic lesion, because conventional SEP studies, utilizing non-cephalic references do not provide clear identification of abnormal sensory levels along the thoracic spinal cord.

Adolescent↗

Quantification and comparison of some natural sphingomyelins by on-line high-performance liquid chromatography/discharge-assisted thermospray mass spectrometry.

Sphingomyelins obtained from bovine brain, chicken egg yolk and bovine milk fat were analysed. Separation was performed by reversed-phase high-performance liquid chromatography utilizing a binary solvent gradient consisting of n-butanol-water-1-propanol-isooctane. Detection was accomplished by light scattering and on-line discharge-assisted thermospray (plasmaspray) ionization mass spectrometry. The positive ion mass spectra exhibit prominent ions related to the amine base structure and fragments which can be utilized for identification of molecular species. The abundance of the fragments containing the fatty acid reflects relatively well the fatty acid composition of natural sphingomyelin mixtures. Bovine brain sphingomyelin has, for example, two distinctive major molecular species composed of C24:1 and C18:0 acids as indicated by the m/z 630.6 and m/z 548.5 ions, respectively. While egg yolk exhibits ions of m/z 520.6 which indicate the presence of C16:0, bovine milk sphingomyelin has several prominent ions of m/z 632.5, 618.6 and 604.7, reflecting the proportions of C24:0, C23:0 and C22:0, respectively.

Animals↗

Glucocorticoid regulation of calcitonin receptor in mouse osteoclast-like multinucleated cells.

Abundant multinucleated cells (MNCs) are formed in cocultures of mouse osteoblastic cells and marrow cells in the presence of 1 alpha, 25-dihydroxyvitamin D3 [1 alpha, 25(OH)2D3], and these cells have the properties of osteoclasts (OCs). In this study using the mammalian OCs, we tried to clarify the role of glucocorticoids (GCs) in calcitonin receptors (CTR) and CT-responsive cAMP production in OCs. Dexamethasone (DEX) dose and time dependently enhanced the specific binding of [125I]salmon calcitonin (sCT). When the MNCs were preincubated with DEX for 24 h, the effect was evident at 10(-9) M and the maximum effect was obtained at 10(-7) M. The effect developed over 12-48 h at doses of 10(-9) and 10(-6) M DEX. The numbers of CTR-positive mononuclear cells and MNCs were not altered by the DEX treatment. Prednisolone and triamcinolone reproduced the DEX effect, but 17 beta-estradiol, progesterone, testosterone, aldosterone, and 1 alpha, 25(OH)2D3 did not. RU486, a GC receptor antagonist, attenuated the effect of DEX to enhance the specific binding of [125I]sCT. From a Scatchard plot analysis, DEX enhanced CTR number (212 +/- 64%) with a minimal change in the affinity to sCT. Autoradiographic studies using [125I]sCT showed that DEX enhanced the density of the grains on the tartrate-resistant acid phosphatase (TRAP)-positive MNCs and mononuclear cells, but not on other types of cells. DEX preincubation also enhanced sCT-stimulated but not prostaglandin E2- or forskolin-stimulated cAMP production.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Use of a remote controlled radiotherapy afterloading system to manage unresectable, metastatic thyroid cancer in the trachea.

We treated a 66-year-old Japanese woman with metastasis from thyroid papillary adenocarcinoma to mediastinal lymph nodes that obstructed the airway by its extensions towards the tracheal carina. Since the patient suffered from severe dyspnea, an endotracheal intubation was inserted and endotracheal radiotherapy was done using a remote controlled afterloading system. The obstruction mass in the trachea almost disappeared and there has been no evidence of regrowth during a follow-up period fo more than 3 years. The patient's management is now detailed.

Adenocarcinoma, Papillary↗

Central nervous system arteriovenous malformations with hereditary hemorrhagic telangiectasia: report of a family with three cases.

A family with central nervous system (CNS) arteriovenous malformations (AVMs) and hereditary hemorrhagic telangiectasia (HHT) is reported. A 46-year-old man had an intracerebral hemorrhage. Cerebral angiography showed one AVM and two angiomas. The HHT was diagnosed because of the concomitant existence of cutaneous telangiectasia. The patient's brother had HHT and paraplegia since the age of 21. Magnetic resonance imaging revealed an old spinal cord hemorrhage. The patient's son with HHT had an intracerebral hemorrhage at age 6. Angiograms showed two AVMs and one angioma. Familial CNS AVMs with HHT are extremely rare. The loci for human leukocyte antigen of the affected cases with HHT were evaluated, and the management of CNS AVMs with HHT is discussed.

Adult↗

Cellular kinetics and lectin distribution in hamster buccal carcinomas.

As part of an evaluation of the progression to malignancy, the cellular kinetics of DMBA-induced tumors in the buccal mucosa of hamsters were examined using 5-bromodeoxyuridine (BrdU), peanut agglutinin (PNA), Ulex europaeus agglutinin I (UEA-I) and wheat germ agglutinin (WGA). BrdU-positive cells were localized in the basal layer in both normal and hyperplastic epithelium, whereas they were distributed from the basal to the prickle cell layer in squamous cell carcinoma (SCC). The extent of BrdU labeling increased as the tissues progressed towards malignancy. PNA and UEA-I showed binding only in the prickle cell layer of normal and hyperplastic epithelium, and WGA showed binding mainly in the prickle cell layer. However, in SCC, PNA and UEA-I showed no binding in the prickle cell layer and WGA binding was observed throughout the epithelium. A study of cellular kinetics using BrdU labeling and the lectin binding pattern may be useful in the evaluation of tissue changes on the way to malignancy.

9,10-Dimethyl-1,2-benzanthracene↗

Parathyroid hormone-related protein during pregnancy and the perinatal period.

To evaluate whether parathyroid hormone-related protein (PTHrP) plays any role in calcium metabolism during pregnancy and the perinatal period, we measured parathyroid hormone (PTH), immunoreactive PTHrP and calcium in maternal serum of women during pregnancy and puerperium, and in maternal and cord serum at delivery. Serum PTH levels in pregnant women were lower than those in nonpregnant women (p < 0.01). However, serum PTHrP levels were similar in the two groups of women. Cord serum total and ionic calcium levels were higher, and cord serum PTH levels were lower compared to maternal values (p < 0.01). Cord serum PTHrP levels were higher than maternal values, and umbilical arterial levels were higher than umbilical venous levels (p < 0.01). Higher levels of PTHrP in umbilical arterial blood than in umbilical venous blood suggest that the main source of cord blood PTHrP may be the fetus. PTHrP is reported to stimulate placental calcium transfer from mother to fetus in animals. The elevated cord blood PTHrP level in association with the decreased PTH level suggests that stimulation of placental calcium transfer by PTHrP may also be operative in humans.

Calcium↗

Fungal metabolites. XIII. Isolation and structural elucidation of new peptaibols, trichodecenins-I and -II, from Trichoderma viride.

Three new groups of peptaibols, trichodecenins, trichorovins and trichocellins, have been isolated from conidia of the fungus, Trichoderma viride. The structures of trichodecenins-I and -II were established by positive-ion fast-atom bombardment, collision-induced dissociation mass spectrometry and two-dimensional NMR spectroscopy. Trichodecenins-I and -II have a (Z)-4-decenoyl group, six amino acid residues and a leucinol moiety in the molecules. Trichodecenin-II was synthesized by the solution-phase method.

Amino Acid Sequence↗

Dermatophytosis in a Steller sea lion (Eumetopias jubatus).

Serious dermatophytosis caused by Trichophyton mentagrophytes was found in a Steller sea lion (Eumetopias jubatus) at Yomiuri Land Marine Aquarium in Tokyo. The external clinical signs were extensive depilation and hyperkeratosis, as well as redness and depigmentation of the skin. Histopathological findings of the skin revealed PAS positive fungal hyphae with septa in the corneum layer of the epidermis. Further microscopic examination suggested that this lesion of the skin was typical chronic dermatophytosis. Based on morphological and growth characteristics, the isolate was identified as Trichophyton mentagrophytes. It was thought that the infection was due to some factors including species and individual specific and environmental factors and so on.

Animals↗

A case of 17 alpha-hydroxylase deficiency with retained menstruation.

A patient with 17 alpha-hydroxylase deficiency (17OHD) who continued to menstruate is reported. A 24-year-old woman who presented with hypertension, hypokalemia and irregular menses had increased plasma ACTH and mineralocorticoids without any increase in glucocorticoids or sex steroids, and a bilateral adrenal enlargement on abdominal X-ray CT. ACTH stimulation test revealed hyperresponse of the metabolites of the mineralocorticoid pathway and blunted or absent response of those of the glucocorticoid and androgen pathway. Almost all of the abnormalities disappeared after dexamethasone administration. While 17OHD is usually known to accompany hypergonadotropic hypogonadism, the patient continued to menstruate, though irregularly. Although human chorionic gonadotropin administration failed to induce response, basal plasma levels of ovarian steroid (estradiol) and gonadotropins as well as response to LHRH stimulation test were all normal. Thus, the clinical and biochemical features of this case is compatible with the partial deficiency of both adrenals and ovaries, being less severe in the latter. A further analysis especially at molecular level is needed to elucidate the basis for the heterogeneity of this disorder.

Adrenal Hyperplasia, Congenital↗

[Bathing in bed accelerates the recovery of skin temperature after ethanol-loading].

Bathing in bed (BB) is an essential nursing technique applied to patients with restricted physical abilities. The aim of this technique is to keep the functions of the skin as an external barrier and to prevent the patients from infection and decubitus. However, the effect of BB on the blood circulation of the skin has not yet been identified, and the data observed are controversial. We have evaluated the effects of BB on the blood circulation of the skin by use of thermography. BB was applied on the right side of the back (RB) in 6 healthy female subjects who exposed both sides of their back (RB and LB) at room temperature. Ethanol was applied on the 5 x 5 cm area of RB and LB after BB, and recovery of the skin temperature was observed. After BB, the average temperature of RB was significantly lower than that of LB. This shows that BB decreases temperature of the skin exposed in the air probably due to the supply of water by washcloth. Recovery of the skin temperature after the ethanol-loading was accelerated on RB. This indicates that BB facilitates the response of the blood vessels in the skin.

Adult↗

Tuberculous liver abscess treated by percutaneous infusion of antituberculous agents.

Tuberculous liver abscess has been reported in only fourteen patients in Japan and in twenty-nine patients outside Japan. Only nine of the non-Japanese patients and none of the Japanese patients have been treated for this condition without laparotomy. We report a patient who developed tuberculous liver abscess during treatment of tuberculous peritonitis. Diagnosis was made by ultrasound-guided aspiration biopsy, and the patient was treated with percutaneous drainage and transcatheter infusion of antituberculous agents. Direct infusion of antituberculous agents has more direct effects in the treatment of an abscess than systemic chemotherapy alone. Therefore, if a percutaneous catheter can be safely placed, the use of transcatheter infusion of antituberculous agents should be considered.

Administration, Cutaneous↗