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Biomedical subjects

M Yoshioka

Publications and source records attributed to M Yoshioka.

At least 73 records · Page 4Linked to original sources
PubMed2001

Three patients with ophthalmoplegia associated with Campylobacter jejuni.

Cranial polyneuropathy is idiopathic in most patients. Idiopathic cranial polyneuropathy is an acute postinfectious syndrome, along with Guillain-Barré syndrome and Miller Fisher syndrome, in which the common preceding pathogen is Campylobacter jejuni. Serum anti-GQ1b antibodies are elevated in Miller Fisher syndrome and Guillain-Barré syndrome with ophthalmoplegia. Three patients with idiopathic cranial polyneuropathy with predominant ocular involvement are presented. C. jejuni isolated from stool specimens belonged to Penner serotypes O:4, O:23, and O:33. Serum anti-GQ1b antibodies were elevated in all patients but demonstrated rapid reduction concomitant with clinical recovery. All patients recovered completely. Because both preceding C. jejuni infection and elevated anti-GQ1b antibodies decreasing with time were seen in all patients, the pathogenesis of idiopathic cranial polyneuropathy with ophthalmoplegia may be similar to that of Miller Fisher syndrome.

Adolescent↗
PubMed2001

Impact of high-intensity exercise on energy expenditure, lipid oxidation and body fatness.

OBJECTIVE: Two studies were conducted to assess the potential of an increase in exercise intensity to alter energy and lipid metabolism and body fatness under conditions mimicking real life. METHODS: Study 1 was based on the comparison of adiposity markers obtained in 352 male healthy adults who participated in the Québec Family Study who either regularly participated in high-intensity physical activities or did not. Study 2 was designed to determine the effects of high-intensity exercise on post-exercise post-prandial energy and lipid metabolism as well as the contribution of beta-adrenergic stimulation to such differences under a real-life setting. RESULTS: Results from Study 1 showed that men who regularly take part in intense physical activities display lower fat percentage and subcutaneous adiposity than men who never perform such activities, and this was true even if the latter group reported a lower energy intake (917 kJ/day, P<0.05). In Study 2, the high-intensity exercise stimulus produced a greater post-exercise post-prandial oxygen consumption as well as fat oxidation than the resting session, an effect which disappeared with the addition of propranolol. In addition, the increase in post-prandial oxygen consumption observed after the high-intensity exercise session was also significantly greater than that promoted by the low-intensity exercise session. CONCLUSION: These results suggest that high-intensity exercise favors a lesser body fat deposition which might be related to an increase in post-exercise energy metabolism that is mediated by beta-adrenergic stimulation.

Adipose Tissue↗
PubMed2001

Combined effects of red pepper and caffeine consumption on 24 h energy balance in subjects given free access to foods.

The effects of red pepper and caffeine ingestion on energy and macronutrient balances were examined in eight Caucasian male subjects. All subjects participated in two randomly assigned conditions: control and experimental (red pepper and caffeine). After ingesting a standardized breakfast, subjects ate three meals ad libitum (lunch, dinner and breakfast) and snacks which were served approximately 2 h after the lunch and dinner over a 24 h period. Two appetizers with or without 3 g red pepper) were given before lunch and dinner, and a drink (decaffeinated coffee with or without 200 mg caffeine) was served at all meals and snacks except for the after-dinner snack. It is also important to note that on the experimental day, 8.6 and 7.2 g red pepper were also added to lunch and dinner respectively. Red pepper and caffeine consumption significantly reduced the cumulative ad libitum energy intake and increased energy expenditure. The mean difference in energy balance between both conditions was 4000 kJ/d. Moreover, the power spectral analysis of heart rate suggested that this effect of red pepper was associated with an increase in sympathetic:parasympathetic nervous system activity ratio. These results indicate that the consumption of red pepper and caffeine can induce a considerable change in energy balance when individuals are given free access to foods.

Adult↗
PubMed2001

Afferent fibers of the hypogastric nerves are involved in the facilitating effects of chemical bladder irritation in rats.

To evaluate the role of bladder afferent fibers in the hypogastric nerves (HGN) in modulation of the micturition reflex induced by chemical bladder irritation, voiding behavior, continuous cystometry, and spinal c-fos expression following intravesical acetic acid instillation were investigated in rats with or without HGN transection. Voiding behavior and continuous cystometry were examined in unanesthetized conscious rats. Following chemical bladder irritation, a significant increase in urinary frequency associated with a marked decrease in the voided volume per micturition, was noted in control rats with the intact HGN, but not in HGN-transected rats. Continuous infusion of acetic acid in control rats elicited irritative bladder responses characterized by a marked decrease in the intercontraction interval and a marked increase in maximal vesical pressure, both of which were absent in capsaicin-desensitized rats. HGN transection prevented the decrease in the intercontraction interval but not an increase in maximal vesical pressure following chemical bladder irritation. Compared with saline infusion, acetic acid infusion caused a significant increase in c-fos expression at L(1) and L(6) of the spinal cord, and HGN transection significantly reduced c-fos expression in the dorsal horn of the spinal cord at L(1) but not at L(6). These results suggest that capsaicin-sensitive bladder afferent fibers in the HGN, which travel through the rostral lumbar spinal cord, have a role in urinary frequency caused by chemical bladder irritation.

Afferent Pathways↗
PubMed2001

Adhesion to and decalcification of hydroxyapatite by carboxylic acids.

Fundamental to the processes of decalcification of or adhesion to mineralized tissues is the molecular interaction of acids with hydroxyapatite. This study was undertaken to chemically analyze the interaction of 1 mono-, 2 di-, 1 tri-, and 2 polycarboxylic acids with hydroxyapatite in an attempt to elucidate the underlying mechanism. Maleic, citric, and lactic acid decalcified hydroxyapatite, in contrast to oxalic acid and the two polycarboxylic acids that were chemically bonded to hydroxyapatite. Solubility tests showed that the calcium salts of the former were very soluble, whereas those of the latter could hardly be dissolved in the respective acid solutions. Based on these data, an adhesion/decalcification concept was advanced that predicts that carboxylic acids, regardless of concentration/pH, either adhere to or decalcify hydroxyapatite, depending on the dissolution rate of the respective calcium salts in the acid solution. This contrasting behavior of organic acids most likely results from their differential structural conformations.

Acrylic Resins↗
PubMed2001

A clinical evaluation of lymphangioma of the large intestine: a case presentation of lymphangioma of the descending colon and a review of 279 Japanese cases.

With the development and widespread use of colonoscopy, lymphangioma of the large intestine has recently been reported frequently. This paper presents some findings from a review of 279 cases of this disease in Japan, including a typical case that we encountered. A 69-year-old female was diagnosed as having lymphangioma of the descending colon based on the findings of a barium enema and a colonoscopy, and the lesion was successfully removed by an endoscopic resection. In the published reports, the etiology of this disease is not clear yet but the age at onset range shows a tendency toward a higher incidence in comparatively older patients and the male-to-female ratio indicates a higher incidence in males. If there is no complication, endoscopic treatment seems to be the preferable procedure for this disease.

Aged↗
PubMed2001

Celiac artery aneurysm: a case evaluated preoperatively with three-dimensional computed tomographic angiography.

In a 63-year-old woman computed tomography (CT) incidentally detected a celiac artery aneurysm approximately 3 cm in diameter. While conventional angiography suggested that the splenic artery and common hepatic artery arose from the celiac artery aneurysm, three-dimensional CT angiography indicated that the aneurysm involved only the mid portion of the celiac artery. Considering the risk of eventual aneurysm rupture, surgery was performed. Aneurysmectomy and devascularization of hepatic, splenic, and celiac arteries were carried out following complete cross-clamping of the celiac artery. The distal segment of the celiac artery was directly anastomosed to the proximal segment in an end-to-end fashion. Histologically, the aneurysm wall showed atheromatous changes. Contrast-enhanced abdominal CT confirmed complete removal of the celiac artery aneurysm, and postoperative angiography confirmed good arterial flow. The patient recovered uneventfully after surgery, with normalization of transiently abnormal hepatic function parameters. In this case of celiac artery aneurysm, three-dimensional CT angiography was found to be valuable in determining the relationships of the aneurysms to important arterial branches.

Aneurysm↗
PubMed2001

Coronary capillary remodeling in non-insulin-dependent diabetic rats: amelioration by inhibition of angiotensin converting enzyme and its potential clinical implications.

Using Otsuka Long Evans Tokushima Fatty (OLETF) rats, a model of human non-insulin-dependent diabetes mellitus (NIDDM) that exhibits hypertension, obesity, hyperglycemia and hyperlipidemia, the role of local angiotensin II in cardiovascular complications at early stages of NIDDM was characterized. OLETF rats were given an angiotensin converting enzyme (ACE) inhibitor, cilazapril (10 mg/kg/day) or vehicle from the age of 5 weeks to 20 weeks. Arteriolar, intermediate and venular capillary proportions were determined by the double-staining method and levels of collagen and non-collagenous proteins were determined by the selective dye-binding method in heart tissues. In OLETF rats at 20 weeks of age, capillary network remodeling (i.e., an increase in arteriolar portions and a decrease in venular portions) and an increase in collagen content were detected. Cilazapril not only exerted favorable effects on markers of diabetes, but also prevented capillary network remodeling and ameliorated the increase in collagen content. These results suggest that 1) capillary network remodeling and increase in extracellular matrix protein levels precede the onset of overt NIDDM in OLETF rats, and 2) angiotensin II may be involved in the pathogenesis of cardiac complications in the early stages of NIDDM.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Detection of endophyte toxins in the imported perennial ryegrass straw.

From 1997 to 1999, 29 cases of disorders were detected in cattle and horses that had been fed ryegrass straw imported from the U.S.A. These animals showed symptoms resembling ryegrass staggers and the clinical signs disappeared after removal of the straw. Endophytic hyphae were detected in the seeds of all straw samples that were responsible for the clinical cases. Lolitrem B concentrations in the straw ranged between 972 and 3740 ppb. Ergovaline concentrations were between 355 and 1300 ppb. Even though the concentrations of lolitrem B were lower than the toxic threshold proposed by Oregon State University in better part of the cases, our observations suggest the possibility that lolitrem B lower than the proposed threshold can bring disorders to sensitive individuals.

Animals↗
PubMed2001

Orthostatic hypertension in patients with type 2 diabetes.

OBJECTIVE: The prevalence and clinical importance of orthostatic hypertension (OHT) in diabetic patients has not been elucidated, in contrast to orthostatic hypotension, which is occasionally found in diabetic patients with autonomic neuropathy. RESEARCH DESIGN AND METHODS: The prevalence and severity of orthostatic hypertension was investigated in 277 Japanese male patients with type 2 diabetes, including 90 hypertensive patients and 128 nondiabetic age-matched male subjects. Patients treated with antihypertensive drugs were excluded from the study. OHT was defined as an increase in diastolic blood pressure (DBP) from <90 to >or=90 mmHg and/or an increase in systolic blood pressure (SBP) from <140 to >or=140 mmHg after standing from supine position. Clinical profiles and several serum biochemical parameters were determined in addition to chest X-rays and electrocardiograms. RESULTS: The prevalence of OHT in normotensive and hypertensive diabetic patients was significantly higher than in control subjects (12.8 vs. 1.8%, P < 0.01, for normotensive patients; 12.6 vs. 11.1%, not significant, for hypertensive patients). Orthostasis induced a mean increase of 6.8 +/- 11.4 mmHg in SBP and 9.1 +/- 5.2 mmHg in DBP in diabetic patients with OHT compared with those without OHT (-1.0 +/- 9.0 and 3.8 +/- 6.6 mmHg, respectively). Vibration sensation in the lower limb was reduced in diabetic patients with OHT, but the percent coefficient of variation of RR interval, cardio-to-thoracic ratio on chest X-ray, and serum triglyceride levels were higher in these patients compared with normotensive diabetic patients without OHT. CONCLUSIONS: Orthostatic hypertension is a novel complication in normotensive diabetic patients and may associate with early stage neuropathy and development of sustained hypertension.

Diabetes Mellitus, Type 2↗
PubMed2001

Expression of matrix metalloproteinase 3 in experimental atherosclerotic plaques.

In atherosclerotic lesions, matrix metalloproteinases produced by foam cells (macrophages) are thought to increase plaque instability, promote plaque rupture, by degradating extracellular matrix. To investigate the relationship between the expression of these proteinases and the histologic appearance of atheromas, immunohistochemical analysis of matrix metalloproteinase 3 and cell-type markers was performed in atherosclerotic plaques induced in rabbit abdominal aortas by high-cholesterol diets and mechanical injury. In addition to an antibody against matrix metalloproteinase 3, RAM-11 and HHF-35 were used to detect macrophages and smooth muscle cells, respectively. Matrix metalloproteinase 3 was expressed diffusely within the plaques with a fibrofatty histologic pattern. In plaques with foam cell accumulation, matrix metalloproteinase 3 was seen in areas rich in foam cells and the smooth muscle cells near the lumen. In the plaques with fewer macrophages, the proteinase was expressed only in such smooth muscle cells. Matrix metalloproteinase 3 was expressed in the smooth muscle cells in plaques of all histologic types, and macrophages also expressed the metalloproteinase when present in significant numbers. These findings suggest that macrophage accumulation plays an important pathophysiologic role in causing the instability of atherosclerotic lesions by increasing the levels of matrix metalloproteinase 3.

Animals↗
PubMed2001

Evidence for involvement of central 5-HT(4) receptors in cholinergic function associated with cognitive processes: behavioral, electrophysiological, and neurochemical studies.

The possible involvement of 5-HT(4) receptors in cognitive function was investigated with a view toward modulating the cholinergic neuronal system. For this purpose, behavioral, electrophysiological, and neurochemical studies were performed in rats. The behavioral study, using a passive avoidance test, demonstrated that the 5-HT(4) receptor agonist SC 53116 (10 microg/rat i.c.v.) had an ameliorative effect on the muscarinic receptor antagonist scopolamine-induced (1 mg/kg i.p.) impairment of learning. The electrophysiological study showed that SC 53116 (1 and 10 microg/rat i.c.v.) enhanced the population spike amplitude in the hippocampal CA1 field evoked by Schaffer collateral stimulation. SC 53116 (10 microg/rat i.c.v.) also augmented the tetanus-induced long-term potentiation (LTP). This augmented LTP was blocked not only by the selective 5-HT(4) receptor antagonist GR 113808 (20 microg/rat i.c.v.) but also by scopolamine (1 mg/kg i.p.). These findings suggest that the functional interaction between the serotonergic system mediated via 5-HT(4) receptors and the cholinergic system associated with cognitive processes exists in vivo. This possibility was further strengthened by neurochemical study using in vivo microdialysis; local administration of SC 53116 (10 and 100 microM) concentration-dependently enhanced the extracellular levels of acetylcholine (ACh) in the hippocampus. SC 53116-induced (10 microM) facilitation of ACh release was prevented by coperfusion of GR 113808 (10 microM). Taken together, the present findings obtained by these different approaches indicate the possibility that the 5-HT(4) receptors are involved in cognitive impairment induced by the cholinergic neuronal system.

Acetylcholine↗
PubMed2001

[Science in diabetes mellitus].

The Citizen Joint Symposium on "Science in Diabetes Mellitus" was held by the Hokkaido Medical Society at Hokkaido University Conference Hall on October 28, 2000. Six speakers, including three medical doctors, a health nurse, a nutritionist and a physical therapist presented the most-update information on diabetes mellitus based on their specialty. The aim of this symposium was to consider how to support the self-management of patients with diabetes mellitus to keep a quality of life.

Diabetes Mellitus↗
PubMed2001

Preparation and characterization of SNO-PEG-hemoglobin as a candidate for oxygen transporting material.

Acellular hemoglobin (Hb) derivates developed as oxygen carriers are known to cause hypertensive reactions due to their nitric oxide (NO) scavenging action. To modulate this undesired activity, we have developed a new Hb derivative, s-nitrosylated polyethylene glycol (PEG)-modified hemoglobin (SNO-PEG-Hb), which can deliver oxygen and NO. After human Hb was modified with PEG to increase its molecular weight, the free sulfhydryl groups of Hb were s-nitrosylated with s-nitrosoglutathione. Administration of unmodified Hb into anesthetized rats caused a hypertensive reaction, while s-nitrosylated Hb derivatives such as SNO-Hb and SNO-PEG-Hb did not raise blood pressure. The plasma half-lives of heme and NO bound to SNO-PEG-Hb were 11.5 and 2.4 hours respectively, indicating that the s-nitrosylated Hb derivative may act as a slow-releasing agent for NO. Based on these findings, SNO-PEG-Hb is a useful candidate for a blood substitute and tool for oxygen therapeutics.

Analysis of Variance↗
PubMed2001

[Blue toe syndrome after coronary artery bypass grafting].

We report three cases of blue toe syndrome (BTS) after coronary artery bypass grafting (CABG). All patients were cyanotic and exhibited painful toes two to four weeks after CABG. They were treated with antiplatelet and anticoagulant agents, and one patient underwent replacement of the abdominal aorta. Thus, BTS may occur after CABG with coronary angiography, extra-corporeal circulation or intraaortic balloon pumping. For the treatment of BTS, surgery remains the most effective option.

Aged↗
PubMed2001

[A family of early childhood-onset Charcot-Marie-Tooth disease type 2].

We reported a man and his son with Charcot-Marie-Tooth disease (CMT) type 2. Their age at onset was about 5 years. Their clinical examinations revealed muscle atrophy and weakness of both distal lower limbs, foot-drop, a reduction of the reflex in both Achilles tendons and sensory impairment of the glove and stocking type. Nerve conduction studies revealed remarkably low amplitude of compound muscle action potential compared to conduction velocity. The nerve biopsy of their sural nerves revealed loss of large myelinated fiber. We presumed that the clinical features of their disease were compatible with CMT2A or 2B. DNA analysis of our family members performed with microsatellite markers linked to the candidate regions of CMT2A and 2B, did not show apparent positive results. We speculate that this family was a novel gene locus of CMT type 2.

Adult↗
PubMed2001

[Intracellular signal transduction mediated via 5-HT and NA receptors].

The present brief review was discussed about the intracellular signal transduction mediated via 5-HT and NA receptors focussing on the mechanism of antidepressants. Recent studies demonstrated that long-term antidepressant treatments resulted in activation of cAMP pathway at several levels including CREB(cAMP response element-binding protein) and BDNF(brain-derived neurotrophic factor). These pathways are elevated via 5-HT and/or NA receptors which directly couple to the cAMP system(5-HT4,6,7 receptors or beta adrenoceptors), or via receptors that lead to activation of Ca(2+)-dependent protein kinase(5-HT2 receptors or alpha 1 adrenoceptors). Such factors could be common targets for many different type of antidepressants. Elucidation of the signal transduction mediated via 5-HT and/or NA receptors, therefore, provide significant information understanding the pathophysiology of depression.

Animals↗