Search PubMed⌕ Search

Biomedical subjects

S Uchiyama

Publications and source records attributed to S Uchiyama.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Exercise training improves activities of daily living in elderly patients with congestive heart failure].

Exercise training which is one of the multidisciplinary interventions for elderly patients with congestive heart failure, plays an important role for improving the quality of life and reducing the re-admission rate of these patients. We assessed the validity of exercise training for the improvement of patient's skeletal muscle functions and activities of daily living along with monitoring cardiac functions. Exercise training programs were performed in 12 patients with congestive heart failure (New York Heart Association class III or IV), including 5 with valvular disease, 4 with dilated cardiomyopathy and 3 with ischemic cardiomyopathy (mean 79 +/- 9 years). All patients were admitted because of exacerbation of congestive heart failure and were treated conventionally. The exercise training program was started after stabilization of their cardiac condition. The medication was not changed during the training period. After exercise training programs, the cardio-thoracic ratio decreased from 63.8 +/- 7.9% to 60.1 +/- 6.9% (p < 0.01), ejection fraction on echocardiography increased from 47.4 +/- 18.2% to 56.0 +/- 17.5% (p < 0.01), and brain natriuretic peptide decreased from 404.8 +/- 267.5 pg/ml to 313.6 +/- 239.5 pg/ml (p < 0.05). The quadriceps muscle power increased from 0.77 +/- 0.36 Nm/kg to 0.97 +/- 0.41 Nm/kg (p < 0.01). The maximum walking distance on flat surface increased from 149 +/- 164 m to 456 +/- 394 m (p < 0.05). In most patients, the activities of daily living, especially mobility, improved. Appropriate exercise training for the elderly patients with congestive heart failure improves activities of daily living and also reduces the amount of required care by the patients.

Activities of Daily Living↗
PubMed2000

[A case of chorea gravidarum with moyamoya disease].

A 16-year-old girl developed acute left choreic movements during her fourth week of pregnancy. She had sometimes had transient ischemic attacks since she was 10 years old. During the eighth week of pregnancy, a brain MRI showed old ischemic lesions deep in the right frontal white matter. Her angiograph revealed a complete obstruction of the terminal portion of the right internal carotid artery with a developed moyamoya net work. After her abortion, all involuntary movements completely subsided. The choreic movements might have been caused not only by ischemia, but also by enhanced dopaminergic sensitivity mediated by elevations in female sex hormones due to pregnancy.

Abortion, Therapeutic↗
PubMed1999

Stabilization of Pseudomonas aeruginosa cytochrome c(551) by systematic amino acid substitutions based on the structure of thermophilic Hydrogenobacter thermophilus cytochrome c(552).

A heterologous overexpression system for mesophilic Pseudomonas aeruginosa holocytochrome c(551) (PA c(551)) was established using Escherichia coli as a host organism. Amino acid residues were systematically substituted in three regions of PA c(551) with the corresponding residues from thermophilic Hydrogenobacter thermophilus cytochrome c(552) (HT c(552)), which has similar main chain folding to PA c(551), but is more stable to heat. Thermodynamic properties of PA c(551) with one of three single mutations (Phe-7 to Ala, Phe-34 to Tyr, or Val-78 to Ile) showed that these mutants had increased thermostability compared with that of the wild-type. Ala-7 and Ile-78 may contribute to the thermostability by tighter hydrophobic packing, which is indicated by the three dimensional structure comparison of PA c(551) with HT c(552). In the Phe-34 to Tyr mutant, the hydroxyl group of the Tyr residue and the guanidyl base of Arg-47 formed a hydrogen bond, which did not exist between the corresponding residues in HT c(552). We also found that stability of mutant proteins to denaturation by guanidine hydrochloride correlated with that against the thermal denaturation. These results and others described here suggest that significant stabilization of PA c(551) can be achieved through a few amino acid substitutions determined by molecular modeling with reference to the structure of HT c(552). The higher stability of HT c(552) may in part be attributed to some of these substitutions.

Amino Acid Substitution↗
PubMed1999

Nitric oxide release from substantia gelatinosa of the rat spinal cord in vitro.

To study characteristics of nitric oxide (NO) release from substantia gelatinosa (SG) in the spinal cord, we measured NO concentration in transverse spinal cord slices of rats using electrochemical NO probes. Electrical stimulation of the dorsomedial white matter adjacent to SG elicited transient current changes in NO probes placed on SG and the amplitude corresponded to a NO concentration of 200-300 pM. This NO release was not affected by the application of antagonists of glutamate or substance P receptors. The NO release in the rats, which were neonatally treated with capsaicin for denervating C-fibers, was significantly smaller than that in control rats. These data suggest that NO is mainly derived from the unmyelinated afferent nerves in the SG of the spinal cord.

Animals↗
PubMed1999

Sciatica caused by cervical and thoracic spinal cord compression.

STUDY DESIGN: Two case reports of sciatica that was considered to be caused by cervical and thoracic spinal cord compression. OBJECTIVES: To point out that sciatica can be an initial major symptom in patients with cervical or thoracic spinal cord lesions. SUMMARY OF BACKGROUND DATA: Usually, tract pain caused by cord compression is considered to be diffuse and does not resemble sciatica. METHODS: Medical history, physical findings, and the results of imaging studies were reviewed in one case of cervical cord tumor and one case of thoracic kyphosis. RESULTS: In both cases, sciatica was the initial and major symptom. Imaging studies showed no lesion in the lumbar spine. In one patient, a cervical dumbbell tumor was found to compress the cervical cord, and in the other the spinal cord was severely compressed at the thoracic kyphosis. The sciatica disappeared immediately after decompression surgery in both cases. CONCLUSIONS: Leg pain resembling sciatica can be caused by cord compression at the cervical and thoracic level. Thoracic kyphosis may be a causative factor in sciatica, in addition to spinal cord tumor and disc herniation, which have been reported previously.

Adult↗
PubMed1999

Cerebrospinal fluid nitric oxide metabolites in painful diseases.

To elucidate the involvement of NO in pain transmission in humans, we measured NO metabolites (nitrite/nitrate) in the CSF of patients with painful diseases using an NO analyzer based on the Griess method. The nitrite/nitrate levels in patients with degenerative lumbar disease (DLD), but not those with fracture or appendicitis, were significantly higher than those in an age-matched control group. The duration of pain in the DLD group was much longer than that in the fracture or appendicitis group. The nitrite/nitrate levels in the middle-aged and elderly DLD patients depended on the duration of pain. These data probably suggest that the duration of pain is critical for the elevation in nitrite/nitrate levels.

Adult↗
PubMed1999

Morphologic limitations of posterior decompression by midsagittal splitting method for myelopathy caused by ossification of the posterior longitudinal ligament in the cervical spine.

STUDY DESIGN: This is a retrospective study of the morphologic limitations of posterior decompression for ossification of the posterior longitudinal ligament in the cervical spine. OBJECTIVES: To determine the morphologic limitations of the posterior approach in the management of ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: Thirty-eight patients who underwent laminoplasty by midsagittal splitting for ossification of the posterior longitudinal ligament were reviewed. Fifteen patients were included in the noncontact group, in which the spinal cord was free of the ossified lesion after posterior decompression. Twenty-three patients were included in the contact group, in which the spinal cord was not free of the ossified lesion even after posterior decompression. METHODS: The preoperative sagittal alignment of the cervical spine and preoperative maximal thickness of ossification were compared between the two groups. In addition, the morphologic limitations of posterior decompression for ossification of the posterior longitudinal ligament were investigated. RESULTS: The following factors were found to contribute significantly to contact between the spinal cord and ossification of the posterior longitudinal ligament after posterior decompression: 1) lordosis of less than 10 degrees or kyphosis in the preoperative sagittal alignment, and 2) preoperative maximal thickness of ossification of more than 7 mm. CONCLUSIONS: Patients who exhibit significant risk factors for continued contact of the spinal cord should be morphologically considered for anterior decompression.

Adult↗
PubMed1999

Biomechanical analysis of the trapeziometacarpal joint after surface replacement arthroplasty.

A biomechanical analysis of the trapeziometacarpal joint was performed in 7 fresh-frozen normal human cadaveric hands to compare the kinematics of the trapeziometacarpal joint before and after surface total joint replacement. Using a 3-space magnetic Isotrak system (Polhemus, Colchester, VT), which provides a 3-dimensional analysis of motion of joints as well as translation, we found that kinematics and stability of the trapeziometacarpal joint could be duplicated by joint surface replacement arthroplasty provided that normal ligament tensions were present.

Arthroplasty, Replacement↗
PubMed1999

Characterization of heparin low-affinity phospholipase A1 present in brain and testicular tissue.

We identified a unique phospholipase A (PLA) with relatively low heparin affinity, which was distinguishable from the heparin-binding secretory PLA2s, in rat, mouse, and bovine brains and testes. The partially purified enzyme was Ca2+-independent at neutral pH but Ca2+-dependent at alkaline pH. It predominantly hydrolyzed phosphatidic acid (PA) in the presence of Triton X-100 and phosphatidylethanolamine (PE) in its absence. When rat brain-derived endogenous phospholipids were used as a substrate, the enzyme released saturated fatty acids in marked preference to unsaturated ones. Consistent with this observation, the enzyme hydrolyzed sn-1 ester bonds in the substrates about 2,000 times more efficiently than sn-2 ones, thereby acting like PLA1. The enzyme also exhibited weak but significant sn-1 lysophospholipase activity. On the basis of its limited tissue distribution, substrate head group specificity and immunochemical properties, this enzyme appears to be identical to the recently cloned PA-preferring PLA1.

Animals↗
PubMed1999

Correlation between symptomatic, radiological and etiological diagnosis in acute ischemic stroke.

OBJECTIVES: The aim of this study was to correlate with the symptomatic, radiological and etiological diagnosis in acute ischemic stroke. SUBJECTS AND METHODS: Two hundred and fifty patients with first-ever ischemic stroke within 24 h of onset were prospectively studied with 3-step diagnoses: 1) symptomatic diagnosis based on the Oxfordshire Community Stroke Project criteria (OCSP), 2) radiological diagnosis (CT or MRI) and 3) etiological diagnosis based on the Lausanne Stroke Registry criteria. RESULTS: Most of the patients with symptoms of total anterior circulation infarcts (TACI), partial anterior circulation infarcts (PACI) and posterior circulation infarcts (POCI) had corresponding lesions on CT or MRI, while only 68% of lacunar infarcts (LACI) patients had small subcortical infarction (SSI). More than 60% of patients with TACI were classified into cardioembolism in the third diagnosis, while the etiology of PACI was either CE or large-artery atherosclerosis (LAA) in equal numbers. Only 58% of LACI patients were classified into small-artery disease (SAD) and 29% of them (30 cases) into LAA, of which 23 patients had lesions other than SSI. The positive predictive value of SAD in the combination of LACI and SSI was 0.78. The etiology of POCI was variable. CONCLUSION: Except for LACI, the symptomatic classification by OCSP corresponds well to the radiological diagnosis. The etiological diagnosis can be predicted by OCSP in TACI and PACI, but it is hard in POCI, and a number of LACI are due to LAA.

Adult↗
PubMed1999

Longitudinal Median Nerve Conduction Studies After Endoscopic Carpal Tunnel Release.

Forty hands of 36 patients who had undergone endoscopic carpal tunnel release (ECTR), utilising Chow's two-portal technique after being diagnosed with idiopathic carpal tunnel syndrome, were subjected to longitudinal median nerve conduction studies. The distal motor latency (DML) was examined pre-operatively on all the hands, which were re-examined at the post-operative 1st, 3rd, 6th and 12th months. Rapid improvement of DML was observed post-operatively in the first three months. These improvements patterns are not much different from those after open carpal tunnel release (OCTR) reported in the literatures. We consider that the data reported herein can be used as standards of DML course after ECTR.

Journal Article↗
PubMed1999

Magnetic resonance imaging of pseudotumors of the craniovertebral junction in long-term hemodialysis patients.

BACKGROUND/AIMS: Pseudotumors of the craniovertebral junction (PTCVJ) are observed in long-term hemodialysis (HD) patients. There are neither criteria for diagnosis nor guidelines for screening. We attempted to determine magnetic resonance imaging (MRI) findings that could be used to detect PTCVJ, to determine the prevalence of PTCVJ, and to evaluate whether destructive spondyloarthropathy (DSA) might be a yardstick for selection of patients for MRI examination for PTCVJ. METHODS: MRI were examined in 19 DSA patients (8 males, 11 females, age 61.4 +/- 7.3 years, HD duration 17.0 +/- 4.4 years) and in 20 sex-, age-, and HD-duration-matched non-DSA patients (9 males, 11 females, age 57.5 +/- 6.6 years, HD duration 17.7 +/- 4.9 years). We evaluated MRI characteristics of PTCVJ according those which occur due to rheumatoid arthritis. RESULTS: PTCVJ were characterized as follows: disappearance of fat pads in the upper region (supradental PTCVJ), intensity change of the 'predental triangle' in the anterior region (predental PTCVJ), and thickening of cruciform ligaments (retrodental PTCVJ). The prevalence of PTCVJ among patients undergoing HD more than 10 years was high (26 out of 39; 66.7%). The prevalence of PTCVJ was not different between DSA and non-DSA groups. CONCLUSION: We verified that the above MRI findings might be helpful in the detection of PTCVJ. These findings were observed frequently and independently also in patients with DSA.

Amyloidosis↗
PubMed1999

Comparison of base specificity and other enzymatic properties of two protozoan ribonucleases from Physarum polycephalum and Dictyostelium discoideum.

Base specificity and other enzymatic properties of two protozoan RNases, RNase Phyb from a true slime mold (Physarum polycephalum) and RNase DdI from a cellular slime mold (Dictyostelium discoideum), were compared. These two RNases have high amino acid sequence similarity (83 amino acid residues, 46%). The base specificities of two base recognition sites, The B1 site (base recognition site for the base at 5'-side of scissile phosphodiester bond) and the B2 site (base recognition site for the base at 3'-side of the scissile bond) of the both enzymes were estimated by the rates of hydrolysis of 16 dinucleoside phosphates. The base specificities estimated of B1 and B2 sites of RNase Phyb and RNase DdI were A, G, U > C and A > or = G > C > U, and A > or = G, U > C and G > U > A, C, respectively. The base specificities estimated from the depolymerization of homopolynucleotides and those from the releases of four mononucleotides upon digestion of RNA coincided well with those of the B2 sites of both enzymes. Thus, in these enzymes, the contribution of the B2 site to base specificity seems to be larger than that of the B1 site. pH-stability, optimum temperature, and temperature stability, of both enzymes are discussed considering that RNase Phyb has one disulfide bridge deleted, compared to the RNase DdI with four disulfide bridges.

Amino Acid Sequence↗
PubMed1999

Eicosapentaenoic acid release from the red alga Pachymeniopsis lanceolata by enzymatic degradation.

Forty-eight species of seaweeds from Japanese waters were screened for the valuable polyunsaturated fatty acids eicosapentaenoic acid (EPA). The eight species that contained the highest levels of these compounds were analyzed in detail. Of all species tested the red alga Pachymeniopsis lanceolata contained the highest EPA concentration, and it was present as both the free and bound forms. EPA constituted 38.7% of total fatty acids, and polar lipids were the main constituent of the total lipids in P. lanceolata. EPA was obtained from the marine algae P. lanceolata by enzymatic hydrolysis of the total lipids extract using phospholipase A2 (PLA2). The release of EPA reached a plateau after 10 min of enzymatic treatment. These results suggest that P. lanceolata is a useful natural source of EPA and that PLA2 treatment is a convenient method for obtaining EPA from the red alga.

Eicosapentaenoic Acid↗