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Biomedical subjects

T Sakai

Publications and source records attributed to T Sakai.

At least 523 records · Page 29Linked to original sources

[A study of soluble form of selectin family in the sera of patients with neuroimmunological disorders].

Members of the selectin family mediate the first step of leukocyte-endothelial cell interaction in inflammatory lesions. Soluble(s) L-selectin, sE-selectin and sP-selectin were examined by monoclonal antibody-based enzyme linked immunosorbent assay on serum samples taken from patients with neuroimmunological disorders, namely, 35 cases of multiple sclerosis (MS), 18 of Guillain-Barré syndrome (GBS), 7 of Miller-Fisher syndrome (MFS), 8 of chronic inflammatory demyelinating polyneuropathy (CIDP), and 25 of human T-lymphotropic virus type-1 associated myelopathy (HAM). The levels of sL-selectin in active phase of MS (2.20 +/- 0.6 mg/ml: p < 0.05) were increased rather than in inactive phase (0.6 +/- 0.25 mg/ml) and control (1.47 +/- 0.24 mg/ml), the levels of sE-selectin in HAM (37.6 +/- 25.7 ng/ml: p < 0.05) were increased, and the levels of sP-selectin were increased in active phase of MS (179.5 +/- 103.8 ng/ml), GBS (151.2 +/- 81.6 ng/ml), CIDP (198.6 +/- 81.9 ng/ml), and HAM (115.3 +/- 73.5 ng/ml). Moreover, the levels of all soluble selectin family are more increased in active phase of MS (sL-selectin 2.20 +/- 0.6 mg/ml: p < 0.05, sE-selectin 44.2 +/- 32.8 ng/ml: p < 0.05, sP-selectin 179.5 +/- 103.8 ng/ml: p < 0.05) than in inactive phase of MS(sL-selectin 0.6 +/- 0.25 mg/ml, sE-selectin 9.8 +/- 2.6 ng/ml, sP-selectin 63.7 +/- 26.6 ng/ml). In conclusion, we have here first demonstrated that levels of all soluble selectin family were increased in the bloods of patients with MS in active phase. In GBS only the levels of sP-selectin were increased. Thus, these findings suggest that soluble selectin family may reflect the disease activity of multiple sclerosis.

Adult↗

Decreased benzodiazepine receptor binding in Machado-Joseph disease.

UNLABELLED: Benzodiazepine receptor binding was assessed in four Japanese men with Machado-Joseph disease. METHODS: The distribution of benzodiazepine receptors was measured by radionuclide imaging (SPECT) after intravenous administration of 123I-iomazenil (Ro 16-0154). RESULTS: SPECT demonstrated decreased binding throughout the cerebral cortex and cerebellum in all patients. Binding potential (receptor concentration x affinity) was diffusely decreased in cerebral cortex, thalamus, striatum and cerebellum compared with control subjects, suggesting that GABAergic function may be decreased globally in these patients. Cerebral blood flow was largely normal, and no cerebral cortical atrophy was evident on MRI. CONCLUSION: Iodine-123-iomazenil SPECT may become a potent method for detecting impairment of the cerebral cortex even before brain perfusion SPECT or MRI can reveal early abnormalities.

Adult↗

Evaluation of serum neutralizing antibodies to bovine coronavirus in cows & their calves using Hmlu-1 cells.

Between 1992 and 1993, 75 paired serum samples from Holstein dairy cows and their calves were collected from Aomori, Tochigi and Okinawa Prefectures, and the neutralizing antibody titres to bovine coronavirus (BCV) were determined using hamster lung (Hmlu)-1 cells. The anti-BCV antibody positive rate in the maternal serum samples was significantly lower (P < 0.001) in Okinawa (72%) than in Aomori (100%) or Tochigi (100%). The geometric mean tire (GMT) of anti-BCV neutralizing antibody was also significantly lower (P < 0.05) in maternal sera from Okinawa (89) than that of Aomori (229) or Tochigi (264). The anti-BCV neutralizing antibody titres in the sera of calves which had ingested the colostrum, significantly correlated with the antibody concentration of the maternal serum samples (P < 0.05). These results suggest an extensive BCV infection among the dairy cattle in these prefectures, with a varied pattern of distribution between the prefectures. Anti-BCV neutralizing antibody in the sera of newborn calves appeared to be transferred from their dams through colostrum.

Animals↗

[A comparison of the grade of laryngeal visualisation;--the McCoy compared with the Macintosh and the Miller blade in adults].

Effectiveness in visualization of the vocal cord during orotracheal intubation with McCoy (McC) compared with Macintosh (Min) and Miller (Mil) blades were investigated. After an institutional review board approval, 117 patients for elective surgery under general anesthesia requiring tracheal intubation were investigated. Five board certified anesthesiologists tried to visualize the vocal cord of a patient three times with the three different types of laryngoscope. Total of 351 intubation attempts were studied. The view obtained at laryngoscopy with each of the three blades was recorded as follows. Grade 1. If most of the glottis is visible. Grade 2. If only the posterior extremity of the glottis is visible. Grade 3. If no part of the glottis can be seen. Grade 4. If not even the epiglottis can be exposed. Eight-two Grade 1 views were obtained with McC, 72 with Mil and 47 with Min, respectively. Thirty-three Grade 2 views were obtained with McC, 36 with Min and 24 with Mil. Two Grade 3 views with McC, 34 with Min and 14 with Mil were obtained. Seven Grade 4 views were obtained with Mil. The grades of laryngeal visualization with McC were significantly lower than those with Min and Mil.

Adolescent↗

[Electroconvulsive therapy decreased bispectral index--a case report].

A 28-year old female schizophrenic patient underwent electroconvulsive therapy (ECT) under propofol anesthesia. She received ECT five times, and Bispectral Index (BIS) was recorded four times out of the five ECT. BIS values (mean +/- SD) were 95.3 +/- 1.3 before anesthesia, 38.0 +/- 13.1 after loss of consciousness, 45.3 +/- 12.7 immediately after ECT and 27.3 +/- 11.6 about two minutes after ECT. In conclusion, ECT may decrease BIS during continuous propofol infusion.

Adult↗

[Determination of the distance between the upper incisors and the laryngoscope blade during laryngoscopy: comparisons of the McCoy, the Macintosh, the Miller, and the Belscope blades].

We compared the distance between the upper central incisors and the laryngoscope blade with the four different types of laryngoscope blade (McCoy, Macintosh, Miller, Belscope). Twenty-three patients scheduled for general anesthesia were studied. The tooth-blade distance was measured when optimum visibility of the glottis was obtained. The visibility was determined according to the Cormack and Lehane grading. The distance with the McCoy and the Belscope was greater than that with the Macintosh or the Miller. The visibility grade was significantly worse with the Macintosh than with the other types of laryngoscope. The results indicate that the McCoy and the Belscope provide less incidence of upper dental injuries and greater visibility than either with the Macintosh or the Miller. Furthermore, the force applied to the handle is thought to be smaller with the McCoy than with the Belscope.

Adult↗

[Meige's syndrome associated with basal ganglia and thalamic functional disorders].

Magnetic resonance imaging (MRI) or single positron emission computed tomography (SPECT) or both were performed and the responses of surface electromyography (EMG) were examined in seven cases of Meige's syndrome. MRI or SPECT or both demonstrated lesions of the basal ganglia, the thalamus, or both in five of the cases. Surface EMG revealed abnormal burst discharges in the orbicularis oculi and a failure of reciprocal muscular activity between the frontalis and orbicularis oculi in all the cases. These findings suggest that voluntary motor control and reciprocal activity in the basal ganglia-thalamocortical circuits are impaired in Meige's syndrome. In addition, good responses were seen to clonazepam, tiapride and trihexyphenidyl in these cases. Therefore, we conclude that dopaminergic, cholinergic, and gamma-aminobutyric acid (GABA) ergic imbalances in the disorders of the basal ganglia and thalamus in Meige's syndrome cause control in the excitatory and inhibitory pathways to be lost, resulting in the failure of integration in reciprocal muscular activity and voluntary motor control. This failure subsequently causes the symptoms of Meige's syndrome.

Aged↗

[The Osaka concept. "Dome osteotomy" with of without labrum resection].

Acetabular dysplasia represents the most common aetiology for secondary osteoarthritis of the hip joint in Japan. On radiographs progress of the disease can be classified in four stages (I to IV). Labral lesions are common accompanying findings in acetabular dysplasia, representing an important prognostic factor. Therefore we routinely use conventional arthrography to classify labral lesions in three types (normal, torn and detached). From 1978 to 1983 a modified Chiari osteotomy of the pelvis (dome osteotomy) was performed in 64 hip joints without arthrotomy. The preoperative radiography showed labral lesions in 66%. After an average follow-up of 4 years, 43 of the 44 patients with a normal or torn labrum showed excellent or good results. On contrast, 50% of the 20 patients with a detached labrum showed fair and poor results only. From 1984 to 1989 an arthrotomy was combined with dome osteotomy in 29 hip joints and labral lesions had to be resected in 16 cases. The results were generally good in patients with arthrosis grade I and II, but in stage III they were only fair. Thus, the success of labral surgery can only be achieved in early stages of dysplasia. Based on our findings dome osteotomy combined with arthrotomy and labral surgery can be recommended in patients with labral lesions and hip dysplasia grade I and II.

Acetabulum↗

[Pain management in home hospice care].

Among 35 cases with terminal home care cancer patients, 23 (65.7%) cases developed pain. Twenty of these cases (87%) were treated with morphine. MS-contin and Anpec (suppositorium) were given to the patients. The two forms were jointly administered in 20% of them. NSAIDS and other adjuvant analgesics were given to 85% of them. Average dose of morphine were 173.5 +/- 357.5 mg. Adverse morphine side effects were treated with medication. In any case morphine administration was not discontinued due to its adverse effects. Some 82% of the patients died at home. No case dropped out of home care due to unsuccessful pain management. Successful pain management is necessary to implement home terminal care, and both patient and family should fully understand the status and prognosis of the incurable disease. Moreover, medical professionals (home care doctors, home care nurses and hospital doctors) should collaborate to form the temporal, adequate and seamless networking in caring and supporting terminal patients and their families.

Feasibility Studies↗

[Sinus bradycardia induced by talipexole hydrochloride in a patient with Parkinson disease].

We report sinus bradycardia induced by talipexole hydrochloride in a 65-year-old man with Parkinson disease. Approximately four hours after he had taken 0.8 mg of talipexole hydrochloride, he acutely developed sleepiness, delusion, akinesia, and faintness associated with hypotension and sinus bradycardia. Another similar episode occurred when he had taken talipexole hydrochloride 1.2 mg/day in combination with a daily dose of 200 mg of levodopa and 20 mg of carbidopa. These symptoms persisted for 12 hours and diminished gradually without any specific treatments. Talipexole hydrochloride, a stimulator of both the D2 and alpha 2 receptors probably induced bradycardia and hypotension in the present case.

Acute Disease↗

Simple and rapid method for determining nicotinamide adenine dinucleotide synthetase activity by high-performance liquid chromatography.

A method is described for the determination of nicotinamide adenine dinucleotide synthetase (NADS) activity in human blood. Using high-performance liquid chromatography (HPLC), the formed NAD is separated from the substrates and the other blood components in less than 13 min. The activity of NADS determined by HPLC is closely correlated with that determined by the conventional spectrophotometric method, which requires two steps of enzyme reaction. The present method is simple and reliable and facilitates the routine analysis of NADS activity.

Adenosine Triphosphate↗

Histone deacetylase inhibitor activates the WAF1/Cip1 gene promoter through the Sp1 sites.

Treatment of cultured cells with trichostatin A (TSA), a specific histone deacetylase inhibitor, induces the histone hyperacetylation and modulates expression of some mammalian genes. We examined the effects of TSA on cell growth arrest, and its relation to expression of the WAF1/Cip1 gene, a potent inhibitor of cyclin-dependent kinases, in a p53-mutated human osteosarcoma cell line MG63. TSA at 500 ng/ml induced growth arrest at both G1 and G2/M phases, and the expressions of the WAF1/Cip1 mRNA and protein. We also examined the changes of acetylated isoforms of histone H4. Dose-response and kinetic analysis suggest a close correlation between the level of histone acetylation and the induction of the WAF1/Cip1 expressions. Using several mutant WAF1/Cip1 promoter fragments, we found that the TSA responsive elements are two Sp1 sites at -82 and -69 relative to the transcription start site. These findings indicate that TSA induces the WAF1/Cip1 promoter through the typical Sp1 sites, in a p53-independent fashion. Furthermore, the Sp1-luc plasmid, containing SV40 promoter-derived three consensus Sp1 binding sites, was markedly activated by TSA, compared to the mutant Sp1-luc plasmid. These results demonstrate that transcriptional activation through the Sp1 sites of the WAF1/Cip1 promoter by TSA coincides with induced hyperacetylation of histone H4.

Animals↗

CAG repeat length and disease duration in Machado-Joseph disease: a new clinical classification.

To evaluate the clinical characteristics of Machado-Joseph disease (MJD) with reference to CAG repeat length and disease duration, we analyzed neurologic findings in 108 patients from 84 families. The majority of MJD patients presented with an ataxic gait as the initial symptom. Dysarthria and nystagmus were observed from an early stage. Bulging eyes, muscle atrophy and bradykinesia developed later. Patients with a shorter CAG repeat length or later onset had more frequent involvement of proprioceptive sensory deficit. Incidence of abnormal reflexes, tones, and proprioceptive sensation was not associated with disease duration, but with CAG repeat length. Based on these results, we propose a new clinical classification: type A (juvenile type), with hyperreflexia and dystonia, but without a proprioceptive sensory deficit; type C (adult type), with hyporeflexia and a proprioceptive sensory deficit, but without dystonia; and type B (intermediate type), the remaining patients with a mixed presentation.

Adult↗

Heterologous expression, purification, and properties of diol dehydratase, an adenosylcobalamin-dependent enzyme of Klebsiella oxytoca.

Recombinant adenosylcobalamin-dependent diol dehydratase of Klebsiella oxytoca overexpressed in Escherichia coli was purified to homogeneity. The enzyme has a low solubility and was extracted from the crude membrane fraction with 1% Brij 35 in a high recovery. Subsequent chromatography on DEAE-cellulose resulted in 4.9-fold purification of the enzyme in an overall yield of 65%. The enzyme thus obtained showed specific activity comparable to that of the wild-type enzyme of K. oxytoca. The apparent molecular weight determined by nondenaturing gel electrophoresis on a gradient gel was 220,000. The enzyme consists of equimolar amounts of the three subunits with apparent Mr of 60,000 (alpha), 30,000 (beta), and 19,000 (gamma). Therefore, the subunit structure of the enzyme is most likely alpha2beta2gamma2. The recombinant enzyme was also separated into components F and S upon DEAE-cellulose chromatography in the absence of substrate. Components F and S were identified as the beta subunit and alpha2gamma2 complex, respectively. Apparent Km for adenosylcobalamin, 1,2-propanediol, glycerol, and 1,2-ethanediol were 0.83 microM, 0.08 mM, 0.73 mM, and 0.56 mM, respectively. The three genes encoding the subunits of diol dehydratase were overexpressed individually or in various combinations in Escherichia coli. The alpha and gamma subunits mutually required each other for correct folding forming the soluble, active alpha2gamma2 complex (component S). Expression of the beta subunit in a soluble, active form (component F) was promoted by coexpression with both the alpha and gamma subunits, probably by coexistence with component S. These lines of evidence indicate that each subunit mutually affects the folding of the others in this heterooligomer enzyme.

Chromatography, Ion Exchange↗

Hypermethylation in the retinoblastoma gene is associated with unilateral, sporadic retinoblastoma.

We previously reported 9 unilateral, sporadic retinoblastomas with hypermethylation in the 5' region of the RB gene, and we found that CpG methylation in the RB promoter inhibits the binding of the retinoblastoma binding factor 1 (RBF-1) and the activating transcription factor (ATF)-like factors, thereby resulting in a considerable reduction in RB promoter activity. In this study, we screened for hypermethylation in 121 additional cases of retinoblastoma, and found 5 tumors with hypermethylation, including 4 unilateral, sporadic tumors, and one hereditary tumor. The hereditary tumor had a germline deletion of one allele, and the hypermethylation was an acquired, epigenetic change in the other allele. Another tumor had hypermethylation restricted to approximately 800 base pairs in the RB promoter region including the essential RBF-1 and ATF sites. The frequency of hypermethylation in unilateral, sporadic tumors was 9.3% combining our previous and present examinations (13 among 140), whereas the frequency was 1.0% in bilateral hereditary tumors (one among 101). The statistical analyses using the chi-square test indicated significant correlation between hypermethylation and unilateral, sporadic tumors (p < 0.05). These results suggest that hypermethylation in the RB gene is always an acquired, epigenetic change and causes about 9% of unilateral, sporadic tumors.

Blotting, Southern↗

Isolation and expression of the gene which encodes a novel enzyme with polymethoxygalacturonate-degrading activity in Trichosporon penicillatum.

The novel gene named PSX1, encoding a new protopectinase with the polymethoxygalacturonase activity, was isolated from Trichosporon penicillatum. Nucleotide sequencing revealed that the PSX1 gene is composed of 1080 bases (360 amino acids, 38,747 Da). The N-terminal amino acid sequences of the open reading frame correspond to a signal peptide and propeptide processed by a Kex2-like proteinase. Mature PPase SX1 was composed of 334 amino acids (36,121 Da). PPase SX1 produced by a S. cerevisiae transformant harboring the PSX1 gene degraded methoxylated polygalacturonic acid as a substrate, but not degraded unmethoxylated polygalacturonic acid.

Amino Acid Sequence↗

Heat shock protein 65 induced by gammadelta T cells prevents apoptosis of macrophages and contributes to host defense in mice infected with Toxoplasma gondii.

We previously reported that gammadelta T cells mediate the expression of endogenous heat shock protein 65 (HSP65) in macrophages of mice with acquired resistance against infection with Toxoplasma gondii. We show here that HSP65 contributes to protective immunity by preventing apoptosis of infected macrophages. Macrophages of BALB/c mice, which readily acquired resistance to T. gondii infection with the low virulence Beverley strain, strongly expressed HSP65, and only a few of these macrophages underwent apoptosis. On the other hand, the BALB/c mice were susceptible to the infection with the high virulence RH strain of T. gondii; their macrophages did not express HSP65 and did undergo apoptosis. Mice depleted of gammadelta T cells using a mAb specific for TCR-gammadelta became highly susceptible to infection even with the Beverley strain. In these mice, HSP65 expression was markedly suppressed, and their infected macrophages died via apoptosis. Apoptosis was induced in cultured macrophages or macrophage cell lines after infection in vitro with the RH strain, whereas apoptosis was prevented when HSP65 was induced in these cells, before infection, by activation with IFN-gamma and TNF-alpha. However, apoptosis associated with infection by T. gondii RH strain was not prevented when HSP65 synthesis was inhibited by introducing an antisense oligonucleotide for this protein into the cells before activation with IFN-gamma plus TNF-alpha. Thus, HSP65 appears to contribute to immunity by preventing the apoptosis of infected macrophages, and the high virulence Toxoplasma appears to have mechanisms that allow these organisms to evade the host defense system by interfering with HSP65 expression.

Animals↗

Butyrate activates the WAF1/Cip1 gene promoter through Sp1 sites in a p53-negative human colon cancer cell line.

Butyrate is a well known colonic luminal short chain fatty acid, which arrests cell growth and induces differentiation in various cell types. We examined the effect of butyrate on the expression of WAF1/Cip1, a potent inhibitor of cyclin-dependent kinases, and its relation to growth arrest in a p53-mutated human colon cancer cell line WiDr. Five millimolar butyrate completely inhibited the growth of WiDr and caused G1-phase arrest. WAF1/Cip1 mRNA was rapidly induced within 3 h by treatment with 5.0 mM butyrate, and drastic WAF1/Cip1 protein induction was detected. Using several mutant WAF1/Cip1 promoter fragments, we found that the butyrate-responsive elements are two Sp1 sites at -82 and -69 relative to the transcription start site. We also found that a TATA element at -46 and two overlapping consensus Sp1 sites at -60 and -55 are essential for the basal promoter activity of WAF1/Cip1. These findings suggest that butyrate arrests the growth of WiDr by activating the WAF1/Cip1 promoter through specific Sp1 sites in a p53-independent fashion.

Base Sequence↗