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Biomedical subjects

H Tachibana

Publications and source records attributed to H Tachibana.

At least 19 recordsLinked to original sources
PubMed1992

Generation of specificity-variant antibodies by alteration of carbohydrate in light chain of human monoclonal antibodies.

A hybridoma line, C5TN, produced human monoclonal antibody of which light chain had N-linked carbohydrate chain within the variable region. Some molecular-weight variants of light chain of the antibody were produced by C5TN variants resistant to cytotoxic effect of concanavalin A. The variant antibodies significantly altered the original cross-reactivity with antigens or lost the ability of antigen binding. The variants variously trimmed their carbohydrate chains by glycosidases, showed the changed reactivity or acquired the ability to bind for antigens. The carbohydrate-deficient antibodies from tunicamycin-treated C5TN and the variant clones behaved in a similar manner on antigen-binding reactivity. Furthermore, comparison of antibodies of which light chains have carbohydrate chains sensitive and resistant to some glycosidases showed that carbohydrate chain in variable region of light chain can influence their reactivity with antigen.

Antibodies, Monoclonal↗
PubMed1992

Efficient in vitro folding of the three-disulfide derivatives of hen lysozyme in the presence of glycerol.

Four derivatives of hen lysozyme, each lacking one native disulfide bond of the four in authentic lysozyme, were produced in Escherichia coli by expressing synthetic mutant genes. In the reoxidation reaction of the reduced derivatives purified from inclusion bodies, the addition of glycerol significantly enhanced the efficiency of folding and 'correct' disulfide bond formation. This enabled simple chromatographical purification of refolded materials. Purified 3SS-derivatives all showed lytic activities and secondary structures comparable to authentic lysozyme, which directly showed that none of the four native disulfide bonds is a prerequisite for 'correct' in vitro folding.

Animals↗
PubMed1992

Analysis of pathogenicity by restriction-endonuclease digestion of amplified genomic DNA of Entamoeba histolytica isolated in Pernambuco, Brazil.

The pathogenicity of 47 strains of Entamoeba histolytica isolated in Pernambuco, Brazil, was examined using the polymerase chain reaction (PCR) followed by restriction-endonuclease digestion. Electrophoretic patterns of PCR products digested with HinfI revealed that all strains were nonpathogenic. The results were entirely in accord with phenotypic properties such as isoenzyme patterns and the failure to bind a pathogenic-isolate-specific monoclonal antibody. When the sensitivity of PCR was examined, amplified products could be detected from template DNA equivalent to five trophozoites. These observations indicate that PCR amplification of genomic DNA and subsequent restriction-enzyme digestion is a useful strategy for obtaining a sensitive and accurate diagnosis. The present study also demonstrates that nonpathogenic strains of E. histolytica predominate in northeastern Brazil.

Animals↗
PubMed1992

Growth stimulating activity of heat shock protein 90 alpha to lymphoid cell lines in serum-free medium.

A growth stimulating factor was purified from the culture supernatant of human-human hybridoma SH-76 cells in serum-free RPMI 1640 medium by the serial use of DEAE anion and heparin affinity chromatographies. The factor was a 85 kDa protein on SDS-polyacrylamide gel electrophoresis. N-terminal amino acid sequence (PEETQTQDQPME) of the protein was coincident with that of heat shock protein 90 alpha (HSP90 alpha). The protein reacted with anti-HSP90 monoclonal antibody. These results suggest that the protein was a member of HSP90 alpha family after taking other circumstantial evidence into account. The protein stimulated the growth of some lymphoid cell lines such as human B-lymphoblastoid cell line HO-323-3 hybridomas derived from HO-323, and several other lymphoid cell lines. There were several lymphoid cell lines which did not respond to the protein. Growth stimulating activity of the protein was heat-unstable and significantly decreased at above 60 degrees C. These are the first data that describe growth-stimulating activity of heat shock protein 90 alpha.

Amino Acid Sequence↗
PubMed1992

Acinar cell carcinoma of the pancreas with elevated serum alpha-fetoprotein levels: a case report and a review of 28 cases reported in Japan.

A 60-year-old male with elevated serum AFP levels is reported. Other tumor markers apart from AFP were normal. Serum AFP did not bind to Con A or Lentil-lectin by affinity chromatography. Abdominal ultrasonography, computed tomography and endoscopic retrograded cholangiopancreatography demonstrated a tumor extending from the body to the tail of the pancreas. The tumor was strongly suggested to be an acinar cell carcinoma of the pancreas, based on the histological findings of the resected specimen. The peroxidase-antiperoxidase method showed cancer cells to be positive for AFP. In Japan, only 27 cases of pancreatic cancer with elevated serum AFP level have been reported. This is the first Japanese case of pancreatic cancer in which the binding of serum AFP to lectins was investigated.

Carcinoma↗
PubMed1992

Detection of pathogenic Entamoeba histolytica DNA in liver abscess fluid by polymerase chain reaction.

A sensitive method for detection of pathogenic Entamoeba histolytica DNA in drained fluids from liver abscess patients, using the polymerase chain reaction (PCR), has been developed. The PCR employs oligonucleotide primers specific for the gene encoding the 30 kDa molecule of pathogenic E. histolytica. Liver abscess fluids (19 samples), from 14 patients with a presumptive amebic liver abscess, were examined microscopically and by the PCR method. Only two of the 19 samples were positive microscopically, whereas all 19 samples tested positive by PCR. This technique can be used to confirm the diagnosis of amebic liver abscess.

Animals↗
PubMed1992

Actively and passively evoked P3 latency of event-related potentials in Parkinson's disease.

Event-related potentials (ERPs) generated during the performance of visual discrimination tasks were studied in 31 patients with Parkinson's disease, 9 patients with Alzheimer's disease, and 37 normal control subjects. Actively and passively evoked P3 components (P3b and P3a) were respectively identified as the components of the P3 response to infrequent target stimuli and infrequent non-target stimuli. Both the P3a and P3b latencies were significantly prolonged by normal aging. Nine of the Parkinson's disease patients showed a P3b latency above the 95% confidence limit of the age-adjusted regression line based on the normal controls, while only on patient had a prolonged P3a latency. In 6 patients with demented Parkinson's disease, the P3b latency was significantly longer than in 15 age-equivalent normal subjects, although no significant difference was found in the P3a latency. On the other hand, patients with Alzheimer's disease showed significant prolongation of both the P3a and P3b latencies compared to the normal controls. Furthermore, there was a significant difference in P3a latency between patients with demented Parkinson's disease and those with Alzheimer's disease. These results suggest that the automatic processing stage associated with P3a may be less impaired than the attention-controlled processing reflected by P3b in patients with Parkinson's disease, and also indicate that there may be some differences in the changes of cognitive processing caused by Parkinson's disease and Alzheimer's disease.

Aged↗
PubMed1992

Regional cerebral blood flow and P3 variables in patients with multiple lacunar infarcts.

We measured regional cerebral blood flow (rCBF) and event-related potentials (ERPs) in 36 patients with multiple lacunar infarcts and 14 age-matched normal subjects. rCBF was measured by the 133Xe inhalation method. ERPs were recorded during visual discrimination tasks using three kinds of stimuli. The patients showed lower mean cortical blood flow than normal subjects especially for the frontal cortex. Nontarget P3 latency in patients was longer than in normal subjects, while no significant differences could be found in target P3 latency between the two groups. Nontarget P3 latency correlated with frontal CBF. These results show that frontal lobe dysfunction may be particularly marked with multiple lacunar infarcts and suggest that reduction of frontal CBF is related to the impairment of the automatic processing associated with the nontarget P3 component.

Aged↗
PubMed1992

Slowly progressive limb-kinetic apraxia with a decrease in unilateral cerebral blood flow.

We report two patients with slowly progressive motor disorders, whose principal manifestations were asymmetric limb-kinetic apraxia and muscle rigidity. In both patients MRI revealed no responsible lesion, whereas single photon emission computed tomography (SPECT) showed a decrease in cerebral blood flow (CBF) in the unilateral hemisphere. One patient with mainly right-sided apraxia had a decreased CBF in the left central region between the frontal and parietal cortices, and the other patient with left-sided apraxia in the right parietal cortex. In agreement with asymmetric clinical symptoms, the regional CBF decrease in the unilateral cortical areas including the frontal and parietal cortices may suggest a degenerative disease, presumably diagnosed as having cortico-basal degeneration.

Aged↗
PubMed1992

Event-related potentials in patients with multiple lacunar infarcts.

We studied event-related potentials (ERPs) occurring in response to attended and unattended stimuli in 31 patients with multiple lacunar infarcts. ERPs were recorded during the performance of visual discrimination tasks using three kinds of stimuli. Each component of P300 response to infrequent nontarget stimuli and P300 response to infrequent target stimuli was defined as non-target P3 or target P3. The non-target P3 latency in patients with multiple lacunar infarcts was significantly longer than in 15 age-equivalent normal subjects, while no significant differences could be found in target P3 latency between patients and normal subjects. From the controlled/automatic standpoint these results suggest that multiple lacunar infarcts are related to impairment of automatic processing reflected by non-target P3, although controlled processing reflected by target P3, is less impaired.

Aged↗
PubMed1992

[Correlation of visual evoked potentials with dementia in Parkinson's disease].

There has been some debate regarding abnormalities in visual evoked potentials (VEP) in Parkinson's disease (PD). To elucidate the mechanism causing abnormal VEP, we investigated the relationship between VEP and mental function in PD patients. Pattern reversal VEP was recorded in PD patients (n = 27) and age-matched control subjects (n = 14). PD patients consisted of two subgroups; PD without dementia (nD-PD; n = 17) and PD with dementia (D-PD; n = 10). Dementia was evaluated according to the criteria for dementia assigned in DSM III-R, and mental faculties were estimated by using the mini-mental state examination (MMSE). In pattern VEP recordings, P100 latency and amplitude were measured for each eye stimulated. No patient or control subject had impairment of corrected visual acuity or ophthalmological disease. There was no significant difference in age among the three groups (D-PD, nD-PD and control subjects). D-PD patients showed significantly prolonged P100 latency compared to nD-PD patients and control subjects (p less than 0.05). With respect to P100 amplitude, no significant difference was shown among the three groups. In PD patients, there was a rough correlation between P100 latency and MMSE score. No correlation was found between P100 amplitude and MMSE score. In control subjects, P100 latency did not correlate with advancing age. In PD patients, nD-PD patients showed a significant correlation between P100 latency and age, whereas D-PD patients presented no correlation. Abnormal VEP in PD has been mostly ascribed to dopaminergic deficiency in the retina.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Three-dimensional surface display with 123I-IMP in corticobasal degeneration].

A 65-year-old right-handed woman was admitted due to gait disturbance. She had suffered from progressive motor clumsiness in the left-sided limbs for four years. On admission, she was mildly demented, but not aphasic. Neurological examination disclosed constructional disability, limb-kinetic apraxia on the left side, and parkinsonism. Brain CT and MRI showed no responsible lesion. Three-dimensional surface display with 123I-IMP demonstrated decreased cerebral blood flow mainly in the right angular gyrus, and mildly in the right central region. She was clinically diagnosed as having corticobasal degeneration. Hypoperfusion in the angular gyrus and central region may account for constructional disability and limb-kinetic apraxia, respectively. Three-dimensional surface display with 123I-IMP appears to be useful for detecting the cortical region.

Aged↗
PubMed1992

Age-related changes in attended and unattended P3 latency in normal subjects.

Event-related potentials to visual attended and unattended stimuli were studied in 37 normal subjects between the ages of 19 and 91. The components of the P3 responses to rare nontarget stimuli and rare target stimuli were measured as P3a and P3b, respectively. Both the P3a and P3b latencies were significantly and positively correlated with age. The N2 finding of age-related latency prolongation was comparable to the P3a changes with age. From the standpoint of the theory of automatic and controlled processing, these results suggest that both automatic processing, as reflected by the P3a, and attentional controlled processing, as reflected by the P3b, are impaired with normal aging.

Adult↗
PubMed1992

[Primary hemangiopericytoma of the chest wall--a case report].

An extremely rare case of a primary hemangiopericytoma of the chest wall was reported. A 40-year-old female without any complaints was detected to have an abnormal shadow in the right chest wall on a chest X-ray film. The tumor was 2.6 x 2.2 x 2.0 cm in size and was resected together with the 8th rib which adhered to the tumor. Postoperative pathohistological examination led to the diagnosis of hemangiopericytoma. Postoperative course was uneventful, and the patient is now doing well and has had no recurrence for 11 months since the operation. A brief review was made on 9 cases collected from the literature.

Adult↗
PubMed1992

[Long-term results of the Blalock-Taussig shunts].

One-hundred and thirty-six patients received the classical Blalock-Taussig shunts between 1980 and 1990. Their age range at operation was 4 days to 12.8 years and their median age was 13 months. The operative mortality rate was 0.7% (1/136). The survivors were followed up from 1 month to 11.5 years, 5.4 years in average. Twenty-five patients required another shunt and the mean interval to that procedure was 2.4 years (modified Blalock-Taussig 23, classical Blalock-Taussig 2, Glenn 1, internal mammary artery-pulmonary artery shunt 1). Forty-five patients received corrective operations, there were four operative deaths (Fontan 2, Rastelli 2). There were 15 late deaths of which three deaths were not cardiogenic. One year after operation, 91.0% of patients remained in well-palliated condition. At three years after operation, 76.4% of patients continued to be in well-palliated condition. There were twelve neonates in this series. Their age range was 4 to 26 days and their median age was 13 days. There was no operative death. Five patients required second shunt. There were two late deaths. At present, six patients continue to be in well-palliated condition 8 months to 9 years after first operation. Angiographic findings showed the stenotic change of the vascular anastomoses in 49.3% (35/71) of patients. This study suggests that polydioxanone suture (PDS) will be useful for the growth of the anastomoses in Blalock-Taussig operation.

Anastomosis, Surgical↗