Biomedical subjects
Publications and source records attributed to S Ohba.
In degloving injuries of the hand, rehabilitation can be delayed due to poor wound healing and partial flap necrosis, if the avulsed tissue is sutured back primarily. By sandwiching a temoroparietal fascial flap between the avulsed flap and the tendons, rehabilitation can be started immediately, even if flap necrosis is present.
A case-control study was conducted and previous epidemiological data were reviewed in order to investigate the dose-response relationship between coffee and the risk of pancreas cancer. The case-control study was community-based and was carried out in Hokkaido, Japan, employing 141 patients with pancreas cancer and 282 controls (two for each case) matched for sex, age and place of residence. The dose-response relationship between coffee (cups/day) and the relative risk of this disease formed a U-shaped curve. The lowest relative risks (0.18 for male and 0.53 for female) were found among "occasional" drinkers. Epidemiological articles published between 1981 and 1993 were selected from Index Medicus using the two key words "coffee" and "pancreas cancer". In many of the previous case-control studies the curve of the dose-response relationship was also U-shaped, when the relative risks were calculated specifically using four or five levels of coffee dose. The nadirs of the relative risks, most of which ranged from 0.5 to 0.7, were found most frequently at small doses (1-2 or 3-4 cups/day). The results of meta-analysis of these studies formed a U-shaped curve. Studies of other types showed almost the same results. Thus it appears that small amounts of coffee might prevent pancreas cancer, whereas large amounts might cause the disease.
A method was developed for performing T1-weighted magnetic resonance imaging with the rapid acquisition with relaxation enhancement (RARE) sequence by altering the excitation flip angle. This method was called variable flip angle turbo spin-echo (VF-TSE) imaging. When the effective echo time corresponds to the first echo, the resolution worsens as the echo train length becomes longer. For this reason, the echo train length was set at three, the repetition time (TR) was shortened (100- 200 msec) to decrease imaging time, and the initial flip angle was adjusted (120 degrees-140 degrees) to improve image quality. Another advantage of this method is that the initial flip angle can be reduced to below 90 degrees when a longer TR is needed. Measured signal intensities for VF-TSE imaging matched theoretic predictions. VF-TSE imaging yielded high contrast-to-noise and signal-to-noise ratios without sacrificing resolution. The VF-TSE technique was useful for breath-hold, three-dimensional, and cardiac synchronization imaging.
Reference lines that correspond to the three reference lines used at computed tomography were determined on 50 normal midsagittal magnetic resonance brain images. Lines were drawn from the mammillary body to the posterior tentorial attachment to the sinus (orbitomeatal), from the center of the pituitary gland to the posterior tentorial attachment to the sinus (Reid baseline), from the mammillary body to the posterior edge of the fourth ventricle (supraorbitomeatal).
The pharmacokinetics of tamsulosin hydrochloride in patients with renal impairment were compared with those in healthy volunteers, and the factors that influenced plasma levels of tamsulosin were elucidated. A single oral dose of 0.2 mg of tamsulosin was given and blood and urine samples were obtained for 36 hours after administration. Unbound plasma concentration of tamsulosin was measured by a combination of equilibrium dialysis and liquid chromatography tandem mass spectrometry methods to examine the effect of protein binding on the pharmacokinetics of tamsulosin. Mean values for maximum concentration (Cmax) and area under the concentration-time curve (AUC) of total drug (Cmax,t and AUC1) in patients with renal impairment were 73% and 211% greater, respectively, than those in healthy volunteers. Mean Cmax and AUC of unbound drug (Cmax,u and AUCu), however, were almost the same in the two groups. A high correlation was found between alpha 1-acid glycoprotein (alpha 1-AGP) concentration and AUCt, but no correlation was found between alpha 1-AGP concentration and AUCu,0-36) or between creatinine clearance (ClCR) and AUCu,0-36). These results show that in patients with renal impairment, the pharmacokinetics of tamsulosin are affected by the change in protein binding that is associated with alteration of plasma alpha 1-AGP concentration, but are not largely affected by the decrease in the renal excretion. Although total tamsulosin levels increased as plasma protein binding increased, unbound tamsulosin levels (which are directly associated with the pharmacologic effects) remained unchanged in these patients.
In isovaleric acidemia (IVA), accumulated isovaleryl-CoA in the mitochondrion induces variable metabolic disturbances. To remove intramitochondrial isovaleryl groups, glycine therapy has been advocated primarily. On the other hand, secondary carnitine deficiency has been documented in this disorder and carnitine supplementation alone has been reported to be effective. In the present study, we administered carnitine and glycine to patients with IVA, and investigated serum carnitine and urinary excretion of total and free carnitine, acylcarnitine profile (i.e., isovalerylcarnitine and acetylcarnitine), and isovalerylglycine. By adding carnitine to glycine supplementation, more isovalerylglycine, not only isovalerylcarnitine, was excreted in the urine. Acetylcarnitine was detected in the urine only when sufficient carnitine was supplemented. We concluded that combined therapy of glycine and carnitine is more effective and safer to eliminate isovaleryl-CoA in IVA than conventional therapy using either glycine or carnitine. Urinary acetylcarnitine concentration might be a good marker indicating the optimal dose of L-carnitine supplementation.
The aim of this study was to determine the phenotypic modulation in mesangial cells of glomeruli damaged by hypertension. Salt-loaded stroke-prone spontaneously hypertensive rats were untreated or treated with a calcium antagonist, manidipine (2 mg/kg/day) for eight weeks. In normotensive Wistar-Kyoto rats, alpha-smooth muscle actin was not expressed in any glomerular cells and a non-muscle myosin heavy chain isoform, SMemb, was slightly expressed in glomerular visceral epithelial cells. In the untreated hypertensive rats, the glomeruli showed sclerosis to various degrees and expressed alpha-smooth muscle actin and SMemb. Normal expression of SMemb in the epithelial cells disappeared. Notably, alpha-smooth muscle actin-positive fibroblast-like cells appeared in the interstitium, especially around the Bowman's capsules. Manidipine ameliorated the glomerulosclerosis and reduced the expression of alpha-smooth muscle actin in mesangial cells. In conclusion, the mesangial cells changed their phenotypes and expressed alpha-smooth muscle actin and SMemb in the glomeruli during the development of hypertensive renal damage. These phenotypically changed mesangial cells are considered to be activated and to produce various kinds of cytokines and extracellular matrix, which leads to glomerulosclerosis. Manidipine attenuated the glomerular damage and the phenotypic changes. The functional relevance of phenotypic changes in these cells should be elucidated in future studies.
An automated screening system for purine and pyrimidine metabolism disorders using high-performance liquid chromatography (HPLC) with column switching is described. The system consists of a reversed-phase column, a cation-exchange column, a column switch, four sets of ultraviolet absorbance detectors, a microcomputer and other conventional equipment. As this system permits the simultaneous determination of urinary orotic acid, uracil, dihydrouracil, pseudouridine, xanthine, 2,8-dihydroxyadenine and succinyladenosine, it offers a useful method for the detection of orotic aciduria, dihydropyrimidine dehydrogenase deficiency, dihydropyrimidinuria, xanthinuria, adenine phosphoribosyltransferase deficiency and adenylosuccinase deficiency.
We report a high-performance liquid chromatographic method with column switching for urinary hypoxanthine and xanthine. Analyses were carried out with both a reversed-phase column and an anion-exchange column connected by a column switch and controlled automatically by a computerized system controller. The relationships between standard concentrations and peak heights were linear in a concentration range of 1 to 1000 nmol/ml. The recovery of hypoxanthine added to urine was 101.1%, and that of xanthine was 98.1%. With our method urinary hypoxanthine and xanthine can be measured accurately without any sample preparation other than filtration.
The antithrombotic effect of a synthetic symmetrical triglyceride having eicosapentaenoic acid (EPA) at positions 1 and 3, and gamma-linolenic acid (GLA) at position 2 was investigated. Administration of the triglyceride significantly increased thrombus formation time and thrombotic occlusion time induced by light irradiation and a fluorescent dye in guinea pigs after 14 days administration compared to that of soybean oil. The antithrombotic effect of the triglyceride was similar to that of EPA ethyl ester. Administration of the triglyceride increased GLA, dihomo-gamma-linolenic acid (DGLA) and EPA contents in plasma and the liver, and the ratio of DGLA to arachidonic acid. These results might be responsible for this antithrombotic effect.
We report on a boy with Rieger syndrome, who had an apparently balanced reciprocal translocation between chromosomes 1 and 4. The clinical manifestations of this patient were characterized by irregular shaped pupils with a prominent Schwalbe line and an umbilical hernia. On cytogenetic studies, he was found to have a de novo reciprocal translocation 46,XY,t(1;4) (q23.1;q25), without visible deletion. His parents had normal chromosomes. A review of both cytogenetic and genetic linkage analyses with Rieger syndrome showed that chromosome 4q was involved. This and other previous reports suggested that the gene for Rieger syndrome is mapped to the 4q25-->4q26 segment adjoining the breakpoint.
The big toe donor site of the wrap-around flap has been reconstructed immediately after elevation of the flap with a snuff-box flap from the dorsum of the recipient hand in 6 patients. Rapid wound healing and a satisfactory appearance were achieved.
The pedicled, extended serratus anterior musculocutaneous flap has been used as a pedicled flap for cervical contracture repair. This flap has a long vascular pedicle, texture and color like those of the cervical surface, and appropriate thickness. This article describes the anatomy of the flap and typical cases.
A patient with head injury presented with computed tomography findings of a diffuse severe infarction of the left cerebral hemisphere in which the cerebral hemodynamics can be evaluated by transcranial Doppler sonography. Serial angiograms revealed a carotid-cavernous fistula, with a complete steal phenomenon. The unusual complication of a traumatic carotidcavernous fistula is discussed.
The effects of IGN-2098 on the healing process of acetic acid-induced gastric ulcer was investigated in comparison with the other histamine H2-receptor antagonists, famotidine and roxatidine acetate HCl, in rats. Ulcer was induced by the injection of acetic acid solution (20%, 0.05 ml). From the 4th day to 17th day after the ulcer induction, drugs were orally administered twice a day. On the 18th day after the ulcer induction, rats were sacrificed to measure the ulcer index macroscopically and to take pictures of the stomachs. Judging from the photographs, the prominence of ulcer the edge was graded into 4 classes, which showed a significant correlation with the histological amount of connective tissue at the ulcer edge. All drugs accelerated the healing of the ulcer, and the effect of IGN-2098 was the most remarkable. In addition, IGN-2098-treatment exhibited more marked inhibition against the prominence of the ulcer edge as compared with the control group. Based on these results, it is concluded that IGN-2098 may be a useful drug for the clinical treatment of ulcer and that the healing acceleration by IGN-2098 without prominence of the ulcer edge may induce no relapse of the ulcer after healing.
In order to evaluate the significance of motor evoked potentials (MEPs) in central nervous system monitoring, the authors conducted two sets of experiments using feline ischemic models. Twenty-three adult mongrel cats were divided into two groups: global (n = 9) and focal ischemic (n = 14) groups. In the case of global ischemia, which was induced by hypovolemic hypotension due to blood letting, deterioration of the D wave began when the mean arterial blood pressure (MABP) approached 45 mmHg, and regional cerebral blood flow (rCBF) dropped to 40% of control. Complete disappearance of the D wave was observed below 30 mmHg in MABP and 20% of control in rCBF. In the case of focal ischemia, which was induced by transorbital occlusion of the middle cerebral artery, the percentages of rCBF at which the D wave disappeared ranged from 9 to 20%. Changes in the amplitude of the D wave--an increase and following decrease--preceded the prolongation of its latency. In contrast with the D wave I waves were too easily affected by ischemia. Moreover, rCBF at the point of disappearance of the I wave varied greatly. In conclusion, the D wave is stable in mild ischemia and is a reliable indicator of critically profound ischemia (%rCBF < 40%). Monitoring the D wave of MEPs seems to be a useful method for avoiding the deterioration of motor function by ischemic insult.
Patients who have a pineal germinoma usually present with symptoms of intracranial hypertension or disturbances in vertical ocular motion but rarely present with amnesia. We recently encountered a case of pineal germinoma accompanied by severe amnesia, but not by hydrocephalus. A 32-year-old, right-handed man was admitted with severe memory disturbance which had gradually worsened in the preceding three months. On admission, he was alert and cooperative. His speech was well preserved and not fabricated. He had neither symptoms of intracranial hypertension or visual disturbance. There was no manifestation of interhemispheric disconnection symptoms. His immediate and semantic memory was preserved, however, his recent and antegrade episodic memory was severely impaired. The amnesia involved both verbal and visual modalities. He could recall only 1 out of 5 objects in 5 minutes. He was orientated to people, but not to time and place. And his motivation was severely affected. Magnetic resonance imaging (MRI) showed a heterogeneously enhanced tumor in the splenium and pineal body that extended into the bilateral ventricular trigon through major forceps and was accompanied by edema in the retrosplenial region. The bilateral crura of the fornix was obscured by the tumor. The enlarged pineal body was slightly compressing the upper colliculus but hydrocephalus was not observed. The tumor, which was partially excised through a right parietal corticotomy, had features typical of a germinoma.(ABSTRACT TRUNCATED AT 250 WORDS)
Five cases of antiphospholipid syndrome with mild headache, but without any neurological deficits and abnormal findings by CT and MRI, were examined by cerebral blood perfusion SPECT using N-isopropyl-p-[123I]iodoamphetamine (IMP). Although three cases were performed quantification of cerebral blood flow with a microsphere method simultaneously, their values were within normal limits. Two of them showed focal low perfusion areas. One case had relatively low perfusion areas in the bilateral occipital lobes and the right temporal lobe, which improved after treatment. One of two had low perfusion in the bilateral occipital lobes. Other three cases only showed uniformity of radioisotope uptake on the cerebral blood perfusion SPECT. Low perfusion areas in antiphospholipid syndrome might be caused by microarterial thrombosis, microvenous thrombosis or spasms, although they could be reversible. As early detection of cerebral abnormality admit to protect irreversible progress of cerebral blood flow, cerebral blood flow SPECT should be performed in cases of antiphospholipid syndrome with neurological complaints.