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Biomedical subjects

H Hashimoto

Publications and source records attributed to H Hashimoto.

At least 991 records · Page 55Linked to original sources

N-myc gene product expression in neuroblastoma.

The presence and distribution of N-myc gene product were studied in 13 neuroblastomas and five ganglioneuroblastomas, using immunohistochemical techniques. Nine tumors (eight neuroblastomas and one ganglioneuroblastoma of composite type) contained neuroblastoma cells with positive nuclei for N-myc protein. Microscopic examination showed that most of the positive neuroblastoma cells seemed to be immature, with no apparent neuronal differentiation. Nine of 11 tumours with amplified N-myc gene copies exhibited tumour cells with positive immunostaining for the N-myc gene product, while none of the seven non-N-myc amplified cases contained immunoreactive tumour cells. The survival of the patients positive for N-myc protein was significantly low compared with that of the negative ones. It is concluded that immunohistochemical staining for the N-myc gene product will facilitate prediction of the prognosis of patients with neuroblastoma.

Adrenal Gland Neoplasms↗

Case report: secondary penile carcinoma.

We report a case of secondary penile carcinoma with primary tumor in the pancreas. Immunoperoxidase tissue staining of carbohydrate antigen 19-9, carcinoembryonic antigen and prostate-specific antigen was useful for diagnosis of original tumor.

Adenocarcinoma↗

Protective effects of a thromboxane synthetase inhibitor, a thromboxane antagonist, a lipoxygenase inhibitor and a leukotriene C4, D4 antagonist on myocardial injury caused by acute myocardial infarction in the canine heart.

We studied the effects of a thromboxane A2 synthetase inhibitor (RS-5186), a thromboxane A2 antagonist (ONO-3708), a 5-lipoxygenase inhibitor (AA-861) and a peptidoleukotriene antagonist (ONO-1078) on infarct size, polymorphonuclear leukocyte infiltration, gross myocardial hemorrhage and arrhythmias in the canine coronary occlusion (2 hour)-reperfusion model (5 hour). The infarct size and risk area were determined by a double staining technique. Thirty minutes prior to occluding the coronary arteries, dogs were randomly assigned to one of the following five groups: the thromboxane A2 synthetase inhibitor group (n = 11) receiving RS-5186 10 mg/kg i.v., the thromboxane A2 antagonist group (n = 12) receiving continuous intravenous infusion of ONO-3708 1 microgram/kg/min, the lipoxygenase inhibitor group (n = 11) receiving AA-861 3 mg/kg i.v., the peptidoleukotriene antagonist group (n = 11) receiving continuous intravenous infusion of ONO-1078 1 microgram/kg/min and the vehicle control group (n = 15). Except for ONO-3708, all the other drugs reduced the infarct size (RS-5186: 26.3 +/- 2.4% of risk area (mean +/- SEM), AA-861: 21.8 +/- 1.3%, ONO-1078: 22.5 +/- 4.4% vs control: 54.0 +/- 6.4%, p less than 0.01 respectively) as well as reducing the area of gross myocardial hemorrhage (RS-5186: 3.9 +/- 2.6% of infarct size, AA-861: 5.1 +/- 2.4%, ONO-1078: 5.2 +/- 2.5% vs control: 22.3 +/- 3.9%, p less than 0.01 respectively). RS-5186 and AA-861 reduced the intensity of polymorphonuclear leukocyte infiltration into the infarcted area, however, neither ONO-3708 nor ONO-1078 had any significant influence.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Euthyroid hypothyrotropinemia in children of short stature.

Unique association of hypothyrotropinemia with euthyroidism was described in 2 children of short stature. Both had a history of intrauterine growth retardation (IUGR), but showed an appropriate growth rate after infancy (5 cm/y). Growth hormone secretion after provocation tests was normal, whereas TSH response to TRH was absent. With a highly sensitive TSH radioimmunoassay (RIA) and a specific RIA for TSH-alpha-subunit, both responded to a high dose of TRH stimulation. Serum thyroid hormones were within the normal range, while prolactin response to TRH was exaggerated. Exogenous thyroxine (T4) supplement in case 1 did not improve his growth rate, indicating absence of hypothyroidism. Case 2 was treated with stanozolol, which accelerated his growth velocity to 8 cm/y. During the treatment, serum T4 gradually decreased to 50% of the initial level, but blunted TSH response to TRH remained unchanged. These results indicate that their thyrotrophs are resistant to TRH stimulation and the pituitary setpoint of TSH release is unusually high. The exact mechanism involved in maintaining euthyroidism despite hypothyrotropinemia remains to be elucidated, but a common history of IUGR appears to play a role in producing this pituitary-thyroid state.

Body Weight↗

Latency from the onset of myocardial ischemia to the rise of serum creatine kinase activity is correlated inversely with infarct size in dogs.

Sixteen dogs were subjected to acute, permanent coronary occlusion to assess the relationship between latency for the rise of serum creatine kinase (CK) activity and infarct size. Serum CK activity was measured every 30 min from 0 h to 6 h and serially afterwards until 72 h after coronary occlusion. The serum CK activity immediately before coronary occlusion (0 h) was 61 +/- 18 (SD, n = 16) (range 37-95) IU/l. It exceeded the normal threshold value (100 IU/l) at 3.7 +/- 1.4 (range 1.5-6) h, increased at a maximal rate at 7.0 +/- 1.2 h and reached a peak value of 1700 +/- 1308 (range 304-5109) IU/l at 11.0 +/- 1.8 h after coronary occlusion. The cumulative CK release (CKr) was 6556 +/- 5984 (range 454-21580) IU/l, indicating that various sizes of infarction were produced. In 7 dogs, the infarct size was determined anatomically with an enzyme staining technique. The latency of the CK rise was significantly (p less than 0.01, n = 16) and inversely correlated with the max dE/dt (r = -0.692), peak CK (r = -0.716) and CKr (r = -0.691). The CKr was correlated well (p less than 0.001, n = 16) with max dE/dt (r = 0.946), peak CK (r = 0.984) and the infarct size (r = 0.912, p less than 0.005, n = 7). Thus, the latency of the rise of serum CK activity was inversely correlated with myocardial infarct size.

Animals↗

Altered acetylcholine and norepinephrine concentrations in diabetic rat hearts. Role of parasympathetic nervous system in diabetic cardiomyopathy.

The concentrations of acetylcholine (ACh) as a parasympathetic marker and norepinephrine (NE) as a sympathetic marker were investigated in the hearts of rats 2, 4, and 8 wk after the induction of diabetes by an injection of streptozocin (STZ; 65 mg/kg i.v.). ACh and NE were measured by high-performance liquid chromatography with electrochemical detection. Diabetic rats showed low body weight and heart weight at 2, 4, and 8 wk and higher heart-to-body weight ratio and bradycardia at 8 wk, almost all of which were normalized after insulin treatment. Myocardial ACh and NE concentrations in the diabetic rats at 2 and 4 wk were not significantly different from those in age-matched control rats. However, ACh and NE concentrations in the diabetic rats at 8 wk significantly increased compared with the control rats. Diabetic rats at 8 wk also had increased myocardial choline concentration and choline acetyltransferase activity and decreased acetylcholinesterase activity. Insulin treatment normalized all of these changes in the diabetic rats. Thus, in STZ-induced diabetes (STZ-D), the concentrations of both cholinergic and noradrenergic neurotransmitters in the myocardium increased. The results of this study confirm a previously reported increase in sympathetic activity to the heart and also indicate that there is an increase in the synthesis and a decrease in the metabolism of ACh in STZ-D and that adequate insulin treatment normalizes these changes.

Acetylcholine↗

The distinct subgroup of patients with rheumatoid arthritis shown by Ig G3-reactive rheumatoid factor.

The reactivity of rheumatoid factor (RF) with immunoglobulins of the IgG3 subclass was examined in 49 patients with rheumatoid arthritis (RA) using two types of IgG3 myeloma (routine and IgG3m-15 allotype). Among 49 patients, serum from eight cases showed positive reactivity with both types of IgG3 myeloma by radio-immunoassay (RIA). The isotype of IgG3-reactive RF was not specific; it belonged to the IgM class as well as the IgG subclasses IgG1, IgG2 and IgG4. The patients with IgG3-reactive RF belonged to the clinically-severe classification of RA, having a high erythrocyte sedimentation rate (ESR), high titre in the RA hemagglutination (RAHA) test, and above all they had low levels of complement. Generally, it is concluded that patients with IgG3-reactive RF have serious arthritis and that IgG3-reactive RF might play an important role in the inflammatory process. Furthermore, it was also shown that the RF-reactive site was not associated with the protein-A binding site of IgG3, since RF reacting with IgG3m-15 reacted similarly with routine IgG3, regardless of the difference of the protein-A binding activity. This was confirmed by adding protein-A to the reaction of RF and IgG3m-15 which binds with protein-A. This suggests that the actual reactive site of RF is different to the site that binds protein-A.

Adult↗

A simplified aluminum stain in paraffin sections of bone from hemodialysis patients.

A new simplified method has been devised for staining aluminum and has been tested in paraffin sections of bone from 60 patients who have undergone hemodialysis. Iliac crest bone fragments were fixed in 20% phosphate-buffered formalin for less than a day and demineralized at room temperature in 10% phosphate-buffered formalin containing 5% formic acid for only 2 to 3 hr. Four-micron paraffin sections, accompanied by positive controls, were stained with Maloney's aluminum stain, the Berlin blue reaction for iron, dylon or Congo red for amyloid and von Kossa's reaction for calcium. Aluminum and iron were demonstrated particularly at the mineralizing front of bony tissues; aluminum in 52 cases, iron in 45. Dylon staining also gave positive results in 52 cases. It is important in determining whether aluminum deposition is present that the von Kossa reaction remains positive even after demineralization. This method may be more useful for demonstrating aluminum in bony tissues than the complicated and time-consuming resin-embedding method currently used.

Aluminum↗

Zoonotic Onchocerca in a Japanese child.

A female Onchocerca was found in histopathological sections of a nodule removed from the foot of a 2-year-old girl in southern Japan. As in previously reported cases in Switzerland, Crimea, Canada, and the USA, evident morphological features of the worm resembled those of Onchocerca gutturosa and O. cervicalis, which are known to exist in cervical ligaments of cattle and horses, respectively, in Japan and elsewhere.

Animals↗

[Histochemical study of external urethral sphincter in the rabbit. Analysis with construction of histograms].

Male rabbit's external urethral sphincter was examined by histochemical muscle fiber typing (myosin ATP-ase staining), and the analysis with construction of histograms regarding to muscle fiber types were performed. Rabbit's external urethral sphincter was predominantly composed of fast twitch (type 2) fibers (87.3%) as a whole. But the proportion of constituent fiber types varied according to the layers, i.e., the slow twitch (type 1) fibers constituted a relatively high percentage (33.4%) in the inner third layer, while few of the type 1 fibers were found in the outer third layer. The all histograms regarding to fiber type in different layers were normal bell-shaped distribution curves. The mena diameter of type 2 fibers (14.7 microns) was evidently larger than that of type 1 fibers (20.5 microns). All three kinds of muscle fibers equally tended to increase in size toward the outer direction, and in every three layers, the diameter of type 2 was larger than that of type 1 also. The definite differences in the proportion of fiber types and fiber sizes between layers may implicate that the inner and outer layers play different roles, i.e., continuous tonic constriction in the former and sporadic strong constriction of short duration in the latter, under different neural regulations. As far as rabbit's external urethral sphincter is concerned, sporadic strong constriction should be mainly dependent on the muscle fibers of large size composing the outer layer, especially the fast twitch fibers. It is possible that the rabbit is so adapted that it could interrupt urination promptly.

Animals↗

Differential coupling to positive inotropic responses of cyclic AMP produced by stimulation of beta 1- and beta 2-adrenergic receptors.

In canine right ventricular muscle, isoproterenol, a nonselective beta-agonist, and T-1583, a selective beta 1-agonist, produced positive inotropic effects (PIE) as full agonists. Their PIEs were antagonized by atenolol, a selective beta 1-antagonist, (pA2 = 7.71 for isoproterenol and pA2 = 7.82 for T-1583). The PIE of T-1583 was also antagonized by practolol, a selective beta 1-antagonist (pA2 = 6.55). Procaterol known as a selective beta 2-agonist gave a biphasic concentration-response curve with a maximum that was approximately half those of isoproterenol and T-1583. The PIE of procaterol at low concentrations (pD2 = 7.93), which maximum was approximately 10% of the maximum of isoproterenol, was antagonized by ICI 118,551, a selective beta 2-antagonist (ICI; pA2 = 8.84) and that at high concentrations (pD2 = 5.12) by atenolol (pA2 = 7.56). Increases in cyclic AMP content produced by isoproterenol were reduced greatly by atenolol and slightly by ICI, whereas those produced by T-1583, which were smaller than those by isoproterenol, were abolished by atenolol but not changed by ICI. Procaterol (10(-7) M) produced an increase in cyclic AMP, which was abolished by ICI but not changed by atenolol, to almost the same extent as procaterol (10(-5) M) did, which was abolished by atenolol and slightly reduced by ICI. These results indicate that increased cyclic AMP through beta 1- but not beta 2-receptors couples well to PIE.

Adrenergic beta-Antagonists↗

Reversal effect of thyroxine on altered vascular reactivity in diabetic rats.

The influence of thyroxine treatment on the altered reactivity of the isolated perfused mesenteric vasculature from streptozocin-induced diabetic rats was examined and compared with that of insulin. After 8 weeks of diabetes, the time when the decreased response to isoproterenol appeared, treatment with thyroxine reversed this decreased response to control levels. However, thyroxine replacement did not reverse the decreased responsiveness to norepinephrine, 5-hydroxytryptamine, acetylcholine, and isoproterenol after 12 weeks of diabetes. On the other hand, insulin replacement improved the vascular responsiveness to these agonists at 8 and 12 weeks. Insulin treatment also reversed the attenuated response to nerve stimulation found in diabetic rats, whereas thyroxine treatment did not improve it. Insulin treatment reversed the decreased plasma thyroid hormone levels similarly as thyroxine treatment. These results suggest that thyroid hormone deficiency is likely to be involved partly in the altered reactivity of the rat mesenteric vasculature at the early period of diabetes. On the other hand, adrenergic neuropathy is not induced by hypothyroidism.

Animals↗

Effects of digoxin on acetylcholine and norepinephrine concentrations in rat myocardium.

The influence of digoxin on the autonomic nervous system was studied in rats by examining its effects on the levels of acetylcholine (Ach), a parasympathetic marker, and norepinephrine (NE), a sympathetic marker, in the rat myocardium. Ach and NE were measured by high performance liquid chromatography with electrochemical detection (HPLC-ECD). Digoxin was injected subcutaneously every day for 4 weeks. The administration of 0.35, 0.75, and 2.5 mg/kg of digoxin reduced Ach concentrations in the right atrium to about 80-90% of the control value. However, there was no change in the activity of choline acetyltransferase (ChAT) or acetylcholinesterase (AchE), or in the concentration of choline (Ch). Injection of 0.1 mg/kg of digoxin had no significant effect on Ach concentration. When 0.75 and 2.5 mg/kg of digoxin were injected, there was a significant increase in NE concentration in the right atrium. Neither 0.1 nor 0.35 mg/kg caused any changes. Digoxin (0.75 and 2.5 mg/kg) increased heart rate to about 110% of the control values. Thus, high doses of digoxin increase the NE concentration but decrease the Ach concentration in the rat heart, and these changes might be related to functional changes in the autonomic nervous system.

Acetylcholine↗

[Some properties of hydrophilic addition-type silicone impression materials].

Addition-type silicone impression materials have the characteristic of low wetting by water; therefore, they are sometimes inconvenient in clinical use. However, hydrophilic addition-type silicone impression materials are said to be improved in this characteristic. In this study, the physical properties of two kinds of hydrophilic addition-type silicone impression materials, namely, Hydrophilic EXAFLEX and EXPRESS, were investigated and compared with the traditional addition-type silicone impression materials. Compression set, strain in compression, consistency, and contact angles of the salivary droplet on the these impression materials were measured in accordance with ADAS no. 19. The following results were obtained: 1. Each compression set of HEM, HEL, EPM, EPL, EPE (hydrophilic addition-type silicone impression materials), having superior property in compression recovering, was less than 0.1%, they were equivalent to one-seventh of that of the traditional addition-type silicone impression materials. 2. Strain in compression of HEM, HEL, EPM, EPF was bigger than that of the traditional addition-type silicone impression materials. 3. Consistency of HEM, HEL, EPM, EPL, EPF was smaller in fluidity than that of the traditional addition-type silicone impression materials. Among all impression materials in this study, only with HEM and HEL could a difference in consistency between wet films and dry films be recognized. 4. Contact angles of all hydrophilic addition-type silicone impression materials were smaller than those of the traditional addition-type silicone impression materials. They were equivalent to two-thirds of that of the traditional addition-type silicone impression materials, and improvement in wetting property of these hydrophilic addition-type silicone impression materials was observed.

Dental Impression Materials↗

Recombinant interferon-gamma is a potent inhibitor of osteoblastic cell functions.

Interleukin-1 and tumor necrosis factor-stimulated bone resorption is mediated by osteoclast-activating factor elaborated by osteoblasts. Recombinant interferon-gamma inhibits stimulation of bone resorption by these cytokines. We examined here the effects of recombinant mouse interferon-gamma (rmIFN-G) on DNA and collagen synthesis, and on alkaline phosphatase (ALP) activity, in the osteoblastic cell line (MC3T3-E1) under confluent culture conditions. Addition of rmIFN-G to the cells markedly inhibited their DNA synthesis and ALP activity in dose- and culture time-related manner. Also we found that rmIFN-G decreased markedly collagen synthesis at day 3 after addition of the agent. These data indicate that rmIFN-G is a potent inhibitor of osteoblastic cell functions.

Alkaline Phosphatase↗