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Biomedical subjects

S Kikuchi

Publications and source records attributed to S Kikuchi.

At least 253 records · Page 14Linked to original sources
PubMed1996

Alteration of G protein subclass mRNAs in methamphetamine-induced behavioral sensitization.

Guanine nucleotide-binding regulatory proteins (G proteins) play an obligatory role in the transmembrane signaling system and are concerned with the neurochemical basis of several psychiatric disorders. We examined the alteration in the mRNA levels of G protein subclasses (Gil alpha, Gi2 alpha and Go alpha) in behavioral sensitized rats using subchronic treatment with methamphetamine (MAP). Adult male Sprague-Dawley rats received intraperitoneal injections of MAP (4 mg/kg) or saline (control) once daily for 14 days. A remarkable increase in the levels of Gi2 alpha mRNA was observed in both sides of striatum at 48 hours after the last injection of MAP. The changes in the Gi2 alpha mRNA levels were not significant at two weeks after the last injection of MAP. The levels of Go alpha and Gil alpha mRNA were not changed at 48 hours and at two weeks after the last injection of MAP. These results suggest that the changes in the Gi2 mRNA level might be responsible for the reinforcement of the generation of stereotyped abnormal behavior by repeated administration of MAP rather than the persistence of the reverse tolerance phenomenon.

Animals↗
PubMed1996

Constitutively activated receptors for parathyroid hormone and parathyroid hormone-related peptide in Jansen's metaphyseal chondrodysplasia.

BACKGROUND: An activating mutation of the receptor for parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHrP) was recently found in a patient with Jansens's metaphyseal chondrodysplasia, a rare form of short-limbed dwarfism associated with hypercalcemia and normal or low serum concentrations of the two hormones. To investigate this and other activating mutations and to refine the classification of this unusual disorder, we analyzed genomic DNA from six additional patients with Jansen's disease. METHODS: Exons encoding the PTH-PTHrP receptor were amplified by the polymerase chain reaction (PCR), and the products were analyzed by gel electrophoresis or direct nucleotide-sequence analysis. Nucleotide changes were confirmed by restriction-enzyme digestion of genomic DNA or the PCR products. RESULTS: The previously reported mutation, which changes a histidine at position 223 to arginine (H223R), was found in genomic DNA from three of the six patients but not in DNA from their healthy relatives or 45 unrelated normal subjects. A novel missense mutation that changes a threonine in the receptor's sixth membrane-spanning region to proline (T410P) was identified in another patient but not in 62 normal subjects. In two patients with radiologic evidence of Jansen's metaphyseal chondrodysplasia but less severe hypercalcemia, no receptor mutations were detected. In COS-7 cels expressing PTH-PTHrP receptors with the T410P or H223R mutation, basal cyclic AMP accumulation was four to six times higher than in cells expressing wild-type receptors. CONCLUSIONS: The expression of constitutively active PTH-PTHrp receptors in kidney, bone, and growth-plate chondrocytes provides a plausible genetic explanation for mineral-ion abnormalities and metaphyseal changes in patients with Jansen's disease.

Base Sequence↗
PubMed1996

Positions of dorsal root ganglia in the cervical spine. An anatomic and clinical study.

STUDY DESIGN: The authors investigated the positions of dorsal root ganglia and the relation of the location to symptoms and to the effects of nerve root infiltration in the cervical spine anatomically and clinically. OBJECTIVES: To clarify normal variation of positions of dorsal root ganglia and the relation of the location of dorsal root ganglia to symptoms and to the effects of nerve root infiltration. SUMMARY OF BACKGROUND DATA: The dorsal root ganglia of the spinal nerve has attracted much attention as an important structure in the mechanisms of radicular symptoms in the lumbar spine. Although the position of the dorsal root ganglia in the lumbar spine has been classified recently, there are few reports regarding the dorsal root ganglia in the cervical spine. METHODS: The positions of dorsal root ganglia were divided into two types: proximally situated and distally situated. The positions of dorsal root ganglia in the anatomic and clinical cases were compared. The relation of the positions of dorsal root ganglia to symptoms and to the clinical effects of nerve root infiltration were analyzed. RESULTS: There was no statistically significant difference in positions of dorsal root ganglia in C6 nerve roots between anatomic and clinical cases. In addition, there was no relation between symptoms and the positions of dorsal root ganglia in clinical cases. However, there was a significant difference in positions of dorsal root ganglia in C7 nerve roots between anatomic and clinical cases. Nerve root infiltration was significantly more effective in the distally situated type of dorsal root ganglia. CONCLUSIONS: This study defined the normal variation of the positions of dorsal root ganglia. The results strongly suggest that some attention should be paid to the position of dorsal root ganglia in the diagnosis and treatment of cervical radiculopathy.

Adult↗
PubMed1996

Syringomyelia as a cause of body hypertrophy.

BACKGROUND: Among 26 patients with communicating syringomyelia who came to our out-patient clinic from April, 1989, to March, 1995, three (11.5%) had hypertrophy in limbs, hands, or feet. One had crossed hypertrophy. We considered the possibility that syringomyelia caused body hypertrophy. METHODS: We searched MEDLINE for articles which mention body asymmetry or hypertrophy, and examined the findings in our own patients. FINDINGS: The site of hypertrophy in our three patients coincided with the site of the neurological and magnetic resonance imaging findings. In addition, the horizontal and vertical location of the syrinx corresponded with the site of all four hypertrophic limbs. We located ten articles in which a diagnosis of syringomyelia was made, and five in which other diagnoses were made. INTERPRETATION: From studying our patients as well as those previously reported, we speculate that some types of body hypertrophy are due to damage, accompanied by stimulation, of the sympathetic neurons in the ipsilateral lateral horn of the spinal cord. Although there are many causes of hypertrophy, we suggest that the possibility of syringomyelia be investigated in patients with body hypertrophy, especially in those with any accompanying neurological abnormality.

Adult↗
PubMed1996

An anatomic study of neuropeptide immunoreactivities in the lumbar dura mater after lumbar sympathectomy.

STUDY DESIGN: The distribution and density of nerve innervation in the lumbar dura mater after lumbar sympathectomy were assessed in wistar rats. OBJECTIVE: To provide basic information on the interaction between sympathetic and sensory nerves in patients with low back pain. SUMMARY OF BACKGROUND DATA: Many studies have indicated that the sinuvertebral nerve has an important role in innervating the tissues around the vertebrae. However, the origin, innervating pattern, and connections between the nerves are still controversial. It is well known that pain is often accompanied with sympathetic symptoms and exaggerated by sympathetic stimuli. Occasionally, anesthetic block at the L2 or L3 sympathetic ganglion relieves low back pain or symptoms associated with low back pain. The authors assessed the changes of the density and distribution of nerve innervation of the lumbar dura mater after lumbar sympathectomy. METHODS: Normal adult rats were sympathectomized at L2-L3. The threshold for thermal noxious pain by hot-plate analgesia test and changes in neuropeptides in the lumbar dura mater and dorsal root ganglia using light microscopic immunohistochemistry were assessed and compared with control rats. RESULTS: In the hot-plate analgesia test, sympathectomized rats increased their hot-plate latency time compared with that of sham-operated rats. Density of calcitonin gene-related peptide immunoreactive fibers in sympathectomy side of the lumbar dura mater decreased to 45.5% compared with the contralateral side. The number and size of calcitonin gene-related peptide immunoreactive cells in dorsal root ganglia showed no difference between sympathectomized and contralateral side. CONCLUSION: Sympathectomy increased the pain threshold and made the sympathectomized rats hypesthetic. A large numbers of sensory fibers innervated the lumbar dura mater via L2-L3 sympathetic nerve in rats. Sympathectomy reduced the number of these nerve fibers in the lumbar dura mater. Sympathetic nerves may play an important role for low back pain involving the lumbar dura mater.

Animals↗
PubMed1996

Spinal intermittent claudication due to cervical and thoracic degenerative spine disease.

STUDY DESIGN: Neurogenic intermittent claudication can be caused by spinal cord compression. In this study, 20 patients with spinal intermittent claudication due to degenerative spine diseases were evaluated. OBJECTIVES: This study clarified the clinical features and pathomechanism of spinal intermittent claudication due to degenerative spine diseases. SUMMARY OF BACKGROUND DATA: Spinal intermittent claudication may either be produced by intrinsic or extrinsic lesions. Little is known about spinal intermittent claudication due to extrinsic lesions such as spinal cord compression. Twenty patients with spinal intermittent claudication, caused by cervical or thoracic lesions, who were given surgical treatment except for one, were studied. Their main subjective symptoms were tightness, weakness, and numbness in the lower limbs and a strangulated sensation in the trunk to lower limbs. The objective findings were occurrence and/or aggravation of spinothalamic signs. METHODS: The gait loading test was performed on these 20 patients. Selective spinal angiography was performed on the patients with thoracic myelopathy and its therapeutic effects were evaluated. A radiographic assessment was made in all patients. RESULTS: The subjective symptoms and objective findings were reproduced by the gait loading test. Selective spinal angiography temporarily relieved or improved the spinal intermittent claudication due to the thoracic myelopathy. Spinal intermittent claudication disappeared immediately after surgical treatment. CONCLUSIONS: Circulatory impairment of the spinal cord seems to be closely related to the etiology of spinal intermittent claudication. Besides providing diagnostic information, selective spinal angiography may also have a temporary therapeutic effect.

Adult↗
PubMed1996

Tranilast suppresses intimal hyperplasia after photochemically induced endothelial injury in the rat.

Intimal thickening in the femoral artery of spontaneously hypertensive rats (SHR) was initiated by endothelial damage induced by the photochemical reaction between green light and systemic rose bengal. This model represents a non-mechanical method of producing vessel wall denudation. Neointima formation was assessed by calculating the cross-sectional area of intima, media and lumen, using computer analysis. Tranilast (30, 100 and 300 mg/kg, p.o.), administered 2 days prior to endothelial injury, reduced intimal area by 29, 62 and 87%, respectively, compared to that of vehicle-treated controls. In cultured SHR-derived vascular smooth muscle cells, tranilast produced concentration-dependent inhibition of mitogenesis, whether stimulated by platelet-derived growth factor, basic fibroblast growth factor, insulin-like growth factor or fetal bovine serum. These results suggest that tranilast may be effective in preventing coronary restenosis.

Animals↗
PubMed1996

Effects of indomethacin administration on bone turnover and bone mass in adjuvant-induced arthritis in rats.

We examined the bone turnover and bone mass in adjuvant-induced arthritis in rats and assessed the effects of indomethacin in this model. One hundred ten SD rats, 6 weeks of age, were assigned to 11 groups and injected with adjuvant or solvent in the right foot. Adjuvant-injected rats were orally administered indomethacin at doses of 0 (vehicle), 0.1 (low), 0.5 (medium), and 1.5 (high) mg/kg body weight from the start (day 0). Animals were sacrificed on days 0, 14 (acute phase), and 28 (chronic phase). In the arthritic-control group, serum osteocalcin level and bone mineral content of the fourth lumbar body (L4) and the femur were significantly reduced on day 14. Serum alkaline-phosphatase was increased on day 28. Trabecular bone volume of L4 was decreased on day 14, and the value was further decreased on day 28. Bone formation rate (BFR/BS) was significantly reduced on day 14, and then osteoclast number (Oc.N/BS) increased on day 28. Indomethacin treatment dose-dependently prevented increases in paw volume and osteoclast number. In the high dose group, these indices were maintained at the same level with those in the normal group. However, indomethacin treatments were not able to maintain the parameters of bone formation such as serum osteocalcin and BFR/BS values, and the trabecular bone mass decrease was only partially prevented. These data clearly indicated both reduced bone formation and increased bone resorption as the causes of bone loss in adjuvant-induced arthritis in rats. Increased bone resorption seemed to be due to the increased activity of prostaglandins, but bone formation defect would be related to other factors in this animal model.

Administration, Oral↗
PubMed1996

Apolipoprotein(a) and pentanucleotide repeat polymorphisms are associated with the degree of atherosclerosis in coronary heart disease.

To evaluate whether a high level of lipoprotein(a) (Lp(a)) is a risk for the development of coronary heart disease (CHD), 94 Japanese patients and 64 age-matched Japanese controls, diagnosed after coronary angiography (CAG), were analyzed with special reference to the relations between the degree of atherosclerosis, Lp(a) levels and the apolipoprotein(a) (apo(a)) genotypes. the degree of atherosclerosis was evaluated based on CAG findings in the following three ways: the number of diseased vessels, the Gensini score, and the presence or absence of vascular ulcers and/or irregular outlines of coronary stenotic lesions. Apo(a) protein sizes and the pentanucleotide (TTTTA) repeat polymorphism in the 5' control region of the apo(a) gene were analyzed. Multivariate predictors for the number of diseased vessels were, in decreased order of significance, plasma Lp(a) levels, history of smoking, hypertension, diabetes mellitus, and body mass index (BMI). Independent factors associated with the Gensini score were Lp(a) levels, BMI, hypertension, and diabetes mellitus. A negative association of Lp(a) levels with apo(a) protein sizes, and higher Lp(a) levels in those homozygous for an allele with 8 8 (TTTTA)-repeats, was found in both the controls and patients. In decreasing order of significance, apo(a) protein sizes, the degree of atherosclerosis, the genotype of the pentanucleotide repeat, and gender were independent predictors of Lp(a) levels in stepwise regression models. Apo(a) protein sizes were a significant predictor, and the genotype homozygous for the 8 (TTTTA)-repeats was a possible predictor, for the degree of atherosclerosis in CHD. These findings support the notion that a high Lp(a) level is a risk for the development of atherosclerosis in CHD.

Alleles↗
PubMed1996

Association between family history and gastric carcinoma among young adults.

The relationship between family history of gastric carcinoma and gastric carcinoma in Japanese under 40 years of age was analyzed. The subjects were 108 gastric carcinoma patients (86% were diffuse type) at 9 hospitals in the Kanto area of Japan. Firstly, incidence of gastric carcinoma among the parents of the subjects were compared with that in the general population. Observed/expected (O/E) ratios (P-value) were 1.8 (0.06) for all subjects, 1.3 (0.62) for male subjects, 2.1 (0.04) for female subjects, 0.5 (0.41) for early carcinoma, 2.6 (P<0.01) for advanced carcinoma, 2.3 (0.22) for intestinal-type carcinoma and 1.7 (0.13) for diffuse-type carcinoma. Association between gastric carcinoma and parents' history of gastric carcinoma was strong among women and regarding advanced carcinoma, and the difference in O/E ratios between early and advanced carcinoma was remarkable. Secondly, factors related to advanced-stage gastric carcinoma were analyzed. Histological type (diffuse and intestinal types) was not related, but family history of gastric carcinoma among parents and grandparents was related to advanced stage, and the relationship was independent of other factors. The odds ratio (95% confidence interval) was 3.3 (1.1-9.9). Family history may be related to stage of gastric carcinoma through its relationship to the manner or speed of the tumor's progression. We hypothesis that some genetic factor exists which is involved both in progression from early to advanced stage and in occurrence of gastric carcinoma.

Adolescent↗
PubMed1996

Serum carnitine and disabling fatigue in multiple sclerosis.

The serum concentrations of total, free and acylcarnitine were compared in 25 patients with multiple sclerosis (MS) and among age- and sex-matched normal controls by the new enzymatic cycling method in order to clarify whether the fatigue in MS might be due to possible carnitine-related fatty acid metabolic abnormalities in the mitochondria of skeletal muscles. Patients with MS were divided into those with and those without excessive fatigue. Levels of total and free carnitine were not significantly different between MS patients and normal controls. Levels of acylcarnitine, whose decrease in chronic fatigue syndrome has been reported, were also similar between MS patients and normal controls. There was no difference in these carnitine levels between MS patients with and without excessive fatigue. We argue that acylcarnitine deficiency and fatty acid metabolic dysfunction in mitochondria are not relevant to the excessive fatigue in patients with MS, and further explanatory investigations are to be sought.

Adult↗
PubMed1996

Prevalence of Parkinson's disease in Hokkaido, the northernmost island of Japan.

The prevalence of Parkinson's disease (PD) was investigated in Hokkaido, the northernmost island of Japan. A pilot case-finding study was carried out to estimate the prevalence in the entire island of Hokkaido (population = 5,643,647) initially, then we surveyed the prevalence at one of the smaller cities, Iwamizawa City (population = 80,417). We ascertained 5,342 cases with PD in Hokkaido and 77 cases in Iwamizawa City, estimating the crude prevalence of 94.7/100,000 in Hokkaido (June 30, 1993) and 95.8/100,000 in Iwamizawa City (April 1, 1994), respectively. We calculated that the crude prevalence rate of PD in Japan in currently close to 100/100,000, but the age-adjusted prevalence is still low, compared with those in Europe and North America.

Adult↗
PubMed1996

Reliability of a questionnaire used to survey allergic disease in school.

The reliability of a questionnaire which contained 21 items concerning asthma and allergies of the nose, skin, and eyes and other questions was evaluated by test-retest method. The questionnaire was the same as one used two years ago in a survey of allergic diseases found among elementary, junior and senior high school students in Shizuoka Prefecture, Japan. In order to evaluate its reliability, calculations were made of proportions of agreement, Cohen's kappa values and intraclass correlation coefficients. Both the proportions of agreement and the kappa values were fair, and all the intraclass correlation coefficients showed high values. The results suggest that there might be a slight effect of age, and that the articles which showed higher kappa values tended to be easy to answer, while the items in which kappa values were lower tended to consist of questions of multiple answers. This questionnaire can be regarded as useful for our original purpose of investigating allergic diseases. Among the kappa values of items, the values regarding diagnosis by doctor tended to be the largest. It was suggested that doctor's diagnosis was strongly convincing for patients. The reliability of this questionnaire survey can be regarded as satisfactory.

Adolescent↗
PubMed1996

Status of health promotion program implementation and future tasks in Japanese companies.

This study was performed to elucidate the status of the implementation of health promotion programs (HPPs) and future tasks in occupational settings in Japan. A survey was conducted using a multiple type questionnaire mailed to 395 companies throughout Japan in 1993. The questionnaire was mailed back, after having been answered anonymously, with a response rate of 59%. Companies with more than 300 employees accounted for 76% of the sample. Approximately 70% of the companies implemented HPPs of which health guidance and fitness programs were the two most frequently adopted programs. Nutrition education and mental health programs seemed to be emphasized as future possibilities. Smoking cessation programs were not as common as segregation policies, such as zoning of smoking areas. Currently, 45% of the companies used only in-house health personnel for HPPs, but the prospective percentage in the future was 24%. Most of the companies shared the cost of HPPs with a Health Insurance Society. Lack of health personnel and budgetary restrictions on HPPs constituted the major barriers to the implementation of HPPs. Small-scale enterprises were noted to be particularly influenced by these barriers.

Attitude to Health↗
PubMed1996

Effects of OP-1206 (prostaglandin E1) on nerve-conduction velocity in the dog cauda equina subjected to acute experimental compression.

The effect of OP-1206, a prostaglandin E1 derivative, on cauda equina function was analyzed in a model for acute cauda equina compression in the dog. An inflatable balloon was placed under the lamina of the seventh lumbar vertebra in the dog and muscle action potential area (MAP area) and nerve-conduction velocity (NCV) were monitored during 2 h of compression and 1.5 h of recovery. OP-1206 was infused systemically at three concentrations. Only the highest concentration (30 ng/kg/min) of OP-1206 could prevent the reduction in NCV. However, this concentration had no similar effect on the MAP area. The data suggest the potential therapeutic use of prostaglandin E1 analogues for the future treatment of intermittent claudication.

Action Potentials↗
PubMed1996

[The use of low dose midazolam for the management of spinal anesthesia].

The present study was designed to evaluate the effects of low dose midazolam (MZ) on memories and ease of management of spinal anesthesia. MZ was administered to 103 patients (ASA 1-2), of whom 50 patients were premedicated with atropine sulfate 0.5mg and pethidine hydrochloride (group P), with 53 patients receiving no premedication (group nP). A double blind randomized trial was conducted with the dose of MZ (0, 0.01, 0.02, 0.04, 0.08 mg.kg-1), and MZ was administered i.v. to patients just prior to spinal puncture. The short-term and long-term memories were impaired after administration of MZ in both groups. But the recovery from impairment of memories was more rapid in the short-term memory than in the long-term memory, suggesting that MZ impairs mainly the acquisition of memories. A dose-dependent decrease in SpO2 was observed in group P. We conclude that MZ is a useful drug to relieve anxiety of patients during surgery, but it accompanies the risk of respiratory depression.

Adolescent↗