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Biomedical subjects

A Saitoh

Publications and source records attributed to A Saitoh.

At least 109 records · Page 6Linked to original sources
PubMed1993

Carbohydrate structures of human alpha-fetoprotein of patients with hepatocellular carcinoma: presence of fucosylated and non-fucosylated triantennary glycans.

Chemical structures of the sugar chains of various human alpha-fetoprotein (AFP) species with different affinity for Concanavalin A (Con A) and Lens culinaris agglutinin (LCA) were examined by pyridylamination of their oligosaccharides and stepwise exoglycosidase digestion. Using reversed-phase and size-fractionation high performance liquid chromatography systems we identified six pyridylamino-sugar chains. The Con A-reactive and LCA-nonreactive species of AFP from patients with hepatocellular carcinoma contained a biantennary sugar chain, and the Con A-reactive and LCA-reactive species had a biantennary one with a fucose residue at the innermost N-acetylglucosamine residue. The Con A-nonreactive and LCA-reactive species contained a biantennary sugar chain both with a bisecting-N-acetylglucosamine residue at the trimannosyl core and with a focus residue at the innermost N-acetylglucosamine residue. The Con A-nonreactive and LCA-nonreactive species contained a fucosylated triantennary sugar chain as a major component, and two minor components: a triantennary sugar chain and a biantennary sugar chain with a bisecting-N-acetylglucosamine residue at the trimannosyl core. Thus, the fucosylated and non-fucosylated triantennary sugar chains were newly identified in human AFP. Essentially identical results were obtained for AFP from the patient with gallbladder carcinoma which metastasizes to the liver. These results indicate that the increment in fucosylation and branching to form new antennae is a characteristic feature of the carbohydrate chains of AFP from patients with neoplastic diseases of the liver.

Carbohydrate Conformation↗
PubMed1993

Use of the recombinant chimera proteins, LacZ-Env and Gag-Env, for immunological studies on HIV-1 infection.

To use Env proteins as antigens for detection of the human immunodeficiency virus type-1 (HIV-1) antibodies, we attempted to overexpress the Env proteins in Escherichia coli. To study the epitopes in the Env proteins recognized by the sera of HIV carriers, various regions of the proviral DNA encoding the Env region were fused to the 3' end of the lacZ gene. The immunoblotting analysis of the LacZ-Env(512-611) and LacZ-Env(721-826) proteins with the 41 positive sera revealed that the former and the latter immunologically reacted with 100 and 78% of the sera, respectively. To avoid rare false-positive reactions due to the LacZ moiety of the fusion protein, we attempted to express the Env(512-611) alone or Gag-Env(512-611) under the control of bacteriophage T7 promoter. Although we could express only a low level of the Env(512-611) peptide in E. coli, we succeeded in producing large amounts of the Gag(121-406)-Env(512-611) and Gag(308-406)-Env(512-611) proteins as chimeric proteins. Both of these chimera proteins strongly reacted with the 41 positive sera. We purified these proteins and analyzed the immunological reactivity by dot blot with the 60 positive sera and the 84 normal sera. As little as 20 ng of the dotted proteins was enough for the reaction with the positive sera, whereas as much as 320 ng of them did not show false-positive reactions with the normal sera. We obtained highly purified Gag-Env proteins with highly specific seroreactivity, which should be useful for diagnosis and prognosis.

AIDS-Related Complex↗
PubMed1993

[A study of methicillin-resistant Staphylococcus aureus (MRSA) infection in urological field].

Out of 110 strains of Staphylococcus aureus isolated from 1985 to 1990, isolation rate of methicillin-resistant S. aureus (MRSA) was investigated. Nineteen strains of 59 S. aureus from outpatients and 20 strains of 51 S. aureus from inpatients were determined as MRSA. Isolation frequency of MRSA from inpatients was increasing in the recent two years. Coagulase type, enterotoxin type and production of toxic shock syndrome toxin-1 (TSST-1) were examined in 22 strains of MRSA. Coagulase type II (86%), enterotoxin type C (68%) and TSST-1 positive strain was most dominant. Susceptibility of MRSA to 4 antimicrobial agents were measured, MRSA were sensitive to vancomycin (VCM), arbekacin (ABK) and minocycline, but resistant to flomoxef. Thirty-four patients from whom MRSA was isolated including 20 patients from urine, 13 from pus and 1 from blood, were analyzed clinically. Pyuria was not recognized in some cases in whom MRSA was isolated from their urine. Concomitant polymicrobial infection was frequently noted in those patients with MRSA in their urinary tract. These facts show that the pathogenic role of MRSA in the urinary tract infection was not significant. On the other hand, when MRSA was isolated from pus or blood, serious infections could be caused by MRSA, especially in compromised host. Regarding the treatment in these cases, administration of VCM or ABK was though to be necessary.

Aminoglycosides↗
PubMed1993

Fucosylation index of alpha-fetoprotein, a possible aid in the early recognition of hepatocellular carcinoma in patients with cirrhosis.

We report here on three patients with cirrhosis for whom an early recognition of hepatocellular carcinoma was made possible by the measurement of the degree of fucosylation (fucosylation index) of alpha-fetoprotein. Increased levels of this index associated with a moderate increment of serum concentration of alpha-fetoprotein were observed in three patients with cirrhosis who showed no indication of hepatocellular carcinoma by several imaging modalities. Four years after the onset of an increase in the fucosylation index, small hepatocellular carcinoma with a tumor diameter less than 2 cm was revealed in case 1. In cases 2 and 3, small hepatocellular carcinomas were detected 24 mo and 9 mo, respectively, after the first sign of the increase in the index. However, the development to hepatocellular carcinoma was not detected in five patients with cirrhosis in whom continuous increments of serum concentration of alpha-fetoprotein with low levels of fucosylation index were observed during the prospective follow-up from 3 to 9 yr. These findings indicated that the fucosylation index of alpha-fetoprotein can be used as an aid in an early recognition of hepatocellular carcinoma, especially in patients with cirrhosis during the follow-up process in which the moderate increment of serum concentration of alpha-fetoprotein is noted.

Carcinoma, Hepatocellular↗
PubMed1993

A method of computing the intersurface distance between opposing teeth.

Conventional methods of clinically evaluating tooth occlusion, employing articulating papers and bite impression materials, do not permit a quantitative analysis the occlusion. To overcome this, the shapes of opposing teeth are digitized in three-dimensions and intersurface distances are evaluated in detail. Computational geometry deals with this as a closest-point problem, i.e. the closest points from each surface point must be found by scanning the opposing surface. This process is, in most cases, quite time consuming. In order to expedite the computations required, we present here an algorithm for this determination, whereby the scan area is successively reduced without complicating the scanning procedure, thus accelerating the search. The efficiency of this algorithm was experimentally proved by comparing its computation time with that of the algorithm previously used.

Algorithms↗
PubMed1992

Recombinant human erythropoietin for autologous blood donation: effects on perioperative red-blood-cell and serum erythropoietin production.

To speed collection of blood for autologous transfusion during elective surgery, patients may be given recombinant human erythropoietin (r-HuEPO). In a controlled trial, we evaluated the effects of r-HuEPO on perioperative red-blood-cell and serum erythropoietin (s-EPO) production in patients donating blood before elective orthopaedic surgery. Patients were assigned randomly to receive no r-HuEPO (12 patients), or 3000 U (4), 6000 U (5), or 9000 U (4) of r-HuEPO intravenously twice a week from the time of the first blood donation. All patients received iron sulphate. 1200 ml blood was collected from each patient in three weekly donations of 400 ml. The 3000, 6000, and 9000 U treatment groups produced 284, 350, and 383 ml, respectively, of red cells during donation, and the untreated controls produced 211 ml. s-EPO concentrations were within the normal range during donation. After surgery, s-EPO concentrations peaked on postoperative day 1 in untreated patients and on day 7 in treated patients; therefore, r-HuEPO may suppress endogenous erythropoietin secretion. Although administration of r-HuEPO increases production of red blood cells, the preoperative anaemia induced by repeated phlebotomy without r-HuEPO may accelerate the postoperative secretion of endogenous erythropoietin.

Adolescent↗
PubMed1992

Chemically induced forestomach papillomas in transgenic mice carry mutant human c-Ha-ras transgenes.

Forestomach papillomas and skin papillomas were induced very efficiently by a single dose administration of the chemical carcinogen methylnitrosourea (MNU) in transgenic mice (rasH2 line) carrying human hybrid c-Ha-ras genes, which encode the prototype p21 gene product. The incidence of forestomach papillomas was dose dependent; when 50 mg/kg of MNU were administered i.p., all of the transgenic mice (56 of 56) developed forestomach papillomas within 12 weeks after administration, whereas 5 and 0.5 mg/kg of MNU induced papillomas in 2 of 19 and 1 of 19 mice, respectively. Nine of 56 transgenic mice (16%) also developed skin papillomas at sites wounded by bites or scratches. Only 1 of 77 nontransgenic littermates developed forestomach papillomas after administration of 50 mg/kg of MNU, and no skin papillomas appeared within 12 weeks after MNU administration. The transgenes (integrated copy number, 5-6) in the tumors developed in 55 of 56 affected transgenic mice (98%) contained at least 1 copy of the transgene that was activated by somatic point mutation at the 12th codon, from GGC (Gly) to GAC (Asp). Because somatic point mutations at the 12th or 61st codon of transgenes have never been detected in normal tissues of transgenic mice thus far examined, these mutational activations of transgenes are tumor-specific events. RNA expression of these activated transgenes was also detected. From these results, it is suggested that somatic mutational activation of the human c-Ha-ras transgene plays a causative role in the occurrence of forestomach and skin papillomas induced by MNU administration in these transgenic mice. This transgenic mouse provides a unique screening system for chemicals that induce or suppress papillomagenesis.

Animals↗
PubMed1992

Hair analysis for drugs of abuse. IV. Determination of total morphine and confirmation of 6-acetylmorphine in monkey and human hair by GC/MS.

The reliable analytical method for total morphine in hair was established by GC/MS-SIM. The calibration curve for morphine in hair showed linear over 0.5-100 ng/mg hair. Though the limit of detection was 0.1 ng/mg hair with an S/N > 3 of the base ion(m/z 429) for morphine, the limit of confirmation by detection of three major ions was 0.5 ng/mg. The hydrolytic extraction of the morphine analogs in hair with 10% HCl for 1 h at 100 degrees C gave quantitative recovery of morphine. The reproducibility of recovery of morphine spiked to the control hair was 2.9-7.3% in a concentration range between 2 and 50 ng/mg hair. The three monkeys were administered once a day with morphine at 10 mg/kg and heroin at 2.5 mg/kg, respectively, for 10 days and their back hair newly grown for 10 weeks was cut for analysis. The levels of total morphine in monkey hair intoxicated with morphine and heroin were 3.4 and 5.2 ng/mg, respectively. Taking their doses into account, it is concluded that the morphine level in hair from monkeys administered with heroin was 6 times higher than that with morphine. In hair from monkeys and humans intoxicated with heroin, 6-acetylmorphine was detected at the level of 0.7-7.2 ng/mg as a major component in hair together with morphine and no heroin. Drug concentrations of sectional hair shaft cut 2 cm each from the root side were compared with the self-reported drug histories of three cases. The results of sectional analysis of heroin abuser's hair suggested that the relationship between the distribution of morphine along hair shaft and the drug use history showed a good correlation, though the accumulation of heroin metabolites in body could result from chronic use of heroin.

Animals↗
PubMed1992

A unique monoclonal antibody that recognizes mature p17 of HIV-1 but not its precursor.

The entire and partial gag regions of human immunodeficiency virus type 1 (HIV-1) were overproduced in Escherichia coli and used for epitope mapping of antibodies against p17. We found that a mouse monoclonal antibody to p17, V17 recognizes the mature p17 but not the unprocessed Gag proteins containing the entire p17 moiety. Further analysis revealed that V17 recognizes the C-terminal 12-amino-acid region of p17 having free C-terminus. This monoclonal antibody may be useful for monitoring the maturation of virus particles.

Antibodies, Monoclonal↗
PubMed1992

A simple method for overproduction and purification of p24 Gag protein of human immunodeficiency virus type 1.

A simple method for the overproduction in Escherichia coli and purification of major core protein p24 of human immunodeficiency virus type 1 (HIV-1) was described. The gag-pol region encoding p24, p15, and protease was fused to 3' end of lacZ gene on plasmid. A LacZ-Gag fusion protein, the major primary product, is designed to be cleaved by the HIV-1 protease coexpressed through frameshifting. In fact, p24 and its immediate precursor, p25, were produced in the cells grown at 25C, but not at 37C. When the gag and pol frames were fused in-frame to express the protease without frameshifting, the main product, a LacZ-Gag-Pol fusion protein, was efficiently processed to give p24 exclusively both at 37C and 25C, suggesting more efficient expression of the protease. Recombinant p24 was purified to near homogeneity by a simple three-step procedure. The amino-terminal sequence of the recombinant p24 was the same as that of p24 deduced from nucleotide sequence, indicating that correct processing occurred in E. coli by the coexpressed protease. The method described here provides a means to obtain a large amount of highly pure p24, which is useful for crystallographic and functional studies, preparation of specific antibody, and diagnostic and prognostic uses.

Chromobox Protein Homolog 5↗
PubMed1992

Differential effect of griseofulvin on interferon-gamma-induced HLA-DR and intercellular adhesion molecule-1 expression of human keratinocytes.

Interferon-gamma (IFN-gamma) induces major histocompatibility complex (MHC) class II antigen and intercellular adhesion molecule-1 (ICAM-1) expression on human epidermal keratinocytes. Griseofulvin, an extensively used antifungal agent, has been used effectively in the treatment of lichen planus, in which keratinocytes express both HLA-DR and ICAM-1 antigens. In this study, we investigated the effect of griseofulvin on IFN-gamma-induced MHC class II antigen and ICAM-1 expression of keratinocytes, and demonstrated that griseofulvin decreased IFN-gamma-induced HLA-DR but not ICAM-1 expression.

Antigens, CD↗
PubMed1992

A case of primary leiomyosarcoma of the heart.

A 53-year-old male was hospitalized with complaints of cough, fever and backache. Two-dimensional echo-cardiography showed a pericardial echo-free space and a mass in the right atrium. Based on the MRI findings showing a pericardial mass originating from the atrial tumor, the final diagnosis of leiomyosarcoma was made by a percutaneous pericardial biopsy. Despite various therapies, the patient died after 3 wk. Because of its rareness (to date only 25 case reports), a premortem diagnosis of primary cardiac leiomyosarcoma is generally difficult. However, we feel that MRI and a subsequent biopsy is quite useful for making an early diagnosis of this disease.

Biopsy, Needle↗
PubMed1992

[Study in predictive posture control during the performance of actions].

In order to maintain an ordinary upright posture, the body's center of gravity must be predicted and controlled on the supporting surface based on synthesis of multiple-sensory inputs. In order to evaluate the accuracy of predictive (feedforward) posture control during the performance of actions, we measured maximal shifts in the body's center of gravity using a force platform in 6 normal adults under two visual conditions (with eyes open and closed) and four standing conditions (one-legged; heel to toe posture; and both legs together or apart). Subjects were asked to perform five kinds of voluntary actions (static standing; head tilting forward, backward and laterally; head turning; bending forward; and maximal inclinations to the anterior, posterior and lateral directions). The smaller the supporting surface, the more markedly displacement of the body's center of gravity was increased upon closing the eyes. This finding suggests that the accuracy of predictive posture control decreases as a result of the reduction in the number of multisensory inputs which determine spatial orientation. Assessing purposive shifts in center of gravity during voluntary actions, we can conclude that the body's center of gravity is accurately controlled even in the presence of head movements under ordinary standing conditions. To evaluate balance during the performance of routine actions, we must devise a better method of discriminating purposive shifts in center of gravity from control disorder errors as well as a method of quantifying the accuracy of feedforward regulation.

Adult↗
PubMed1992

[Successful management of choriocarcinoma of the testis with brain metastasis: a case report].

A 32-year-old Japanese male consulted a clinic complaining of gynecomastia. Right painless scrotal swelling was also detected. Right high orchiectomy was performed, then the surgical specimen was histopathologically confirmed as choriocarcinoma and mature teratoma. The imaging revealed cerebral, pulmonary, retroperitoneal metastases. After 3 courses of combination chemotherapy with cisplatin, etoposide and peplomycin (PEP therapy), the brain metastasis completely disappeared and the serum titer of the tumor markers such as beta-HCG became normal. The regression rates of lung and retroperitoneal metastases were 68% and 27%, respectively. Therefore, retroperitoneal lymph node dissection was performed. After the 5th course of PEP therapy, lung metastases disappeared completely. Until the present, no evidence of disease has persisted. The PEP therapy, which is a salvage therapy for refractory testicular cancer, was performed as first-line chemotherapy in this case. It was an excellent modality against choriocarcinoma, along with the surgical treatment.

Adult↗
PubMed1992

[Detection of glycosylated protein of renal tissues using NBT reaction in STZ-induced diabetic rats].

We are carried out to determine the detection of glycosylated protein of renal tissues using nitroblue tetrazolium (NBT) reaction in streptozotocin (STZ)-induced diabetic rats. The levels of glomerular non-enzymatic glycosylation were measured by thiobarbituric acid (TBA) method. There was no significant difference in the intensity of NBT in renal tissues between the 4-week diabetic rats and the same age control rats. The intensity of NBT in the glomerular mesangial areas and capillary walls was marked in 12-week diabetic rats. The staining of NBT was also observed in the tubular epithelial cells in 4- and 12-week diabetic rats. The levels of glomerular non-enzymatic glycosylated protein in 4- or 12-week diabetic rats were significantly greater than those in the same age control rats. It appears that the non-enzymatic glycosylation of renal tissues increased in the early stage of diabetic nephropathy, i.e. 4- or 12-week diabetic rats. It is concluded that the non-enzymatic glycosylation may play an important role in the initiation of renal injuries in diabetic nephropathy.

Animals↗
PubMed1992

[Evaluation of the sensitized condition of patients with allergic diseases in Okinawa using the MAST allergy system].

We determined, using the MAST system, specific IgE antibodies to allergens in the circulating blood of 127 patients with bronchial asthma, allergic rhinitis and atopic dermatitis in Okinawa. The positive rates to inhalant allergens in all patients examined by the MAST system were as follows: Dermatophagoides farinae 65%, house dust 58%, cat epithelium 17% and Japanese cedar 9%. In addition, the positive rates to food allergens found in all patients were as follows: wheat 16%, shrimp 14%, egg white, rice and crab 12%. The average number of positive allergens in the patients with atopic dermatitis was larger than that in those with allergic respiratory diseases only. The above five specific IgE antibodies were detected simultaneously in 12 (9%) of the 127 patients. In addition, the average number of overlapping positive allergens was 2.0 in all patients. From these results, it was suggested that the number of overlapping positive allergens in patients on Okinawa is smaller than in other areas of Japan as compared with other papers.

Adolescent↗