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Biomedical subjects

K Nakata

Publications and source records attributed to K Nakata.

At least 415 records · Page 23Linked to original sources
PubMed1990

A novel diagnostic method of Pneumocystis carinii. In situ hybridization of ribosomal ribonucleic acid with biotinylated oligonucleotide probes.

The reactivity and specificity of the in situ hybridization of ribosomal RNA in the diagnosis of Pneumocystis carinii were investigated. Three complementary oligonucleotide probes, 22 and 25 nucleotides long, corresponding to the species specific regions of 5S and 18S ribosomal RNA of Pneumocystis carinii were synthesized and labeled with biotinylated dUPT at the 3' termini. In situ hybridization was performed on formalin-fixed paraffin-embedded human lung tissues using the mixture of these probes and detected with the avidin-biotin peroxidase complex method. The reactions were positive in all 12 cases of Pneumocystis carinii pneumonia, but in none of the infections with other pathogenic agents, including virus (6 cases), mycobacteria (4 cases), protozoa (4 cases) and fungi (8 cases). The reactivity and specificity of this method was comparable with that of immunohistochemistry using a monoclonal anti-human Pneumocystis carinii antibody. Because the specificity of in situ hybridization is based on nucleotide sequences of ribosomal RNAs, that are constant among species, contrary to morphology of protista or expression of antigens, it should complement conventional staining and immunohistochemical methods, and provide a useful tool for the diagnosis of Pneumocystis carinii.

Antibodies, Monoclonal↗
PubMed1990

[Clinical significance of determination of serum RNase activities in patients with eosinophilia--II. Measurements using polyuridylic acid and polycytidylic acid as substrates].

The activities of RNase (RNase-U and RNase-C) were determined in the serum and leukocytes of 277 patients with 14 cases of various kinds of eosinophilia (not less than 10(3)/microliters), 28 cases of chronic myelocytic leukemia (CML), using polyuridylic acid and polycytidylic acid as synthetic substrates according to the method of Raddi et al. Serum RNase-U activity, serum RNase-C activity and the activity ratio (U/C x 10(-3)) were 55 +/- 14 U, 1,280 +/- 235 U and 44 +/- 11 (mean +/- SD), 196 +/- 137, 1,992 +/- 1,134 U and 97 +/- 38, and 110 +/- 50 U, 1,854 +/- 625 U and 65 +/- 13 for normal subjects, eosinophilia and CML (untreated), respectively. U/C ratio in eosinophilia and CML (untreated) showed a highly significant positive correlation (p less than 0.001) with peripheral eosinophil count; the activity of serum RNase-U per cells in the supernatant of eosinophil homogenate rose significantly (p less than 0.001) compared with that of lymphocytes or granulocytes. Besides, serum and eosinophil RNase-U had a similar optimal pH. These results suggested that serum RNase-U in eosinophilia originated mostly from eosinophils and its rise was correlated strongly with the increase in eosinophils.

Clinical Enzyme Tests↗
PubMed1989

Cloning and characterization of the carbapenem biosynthetic genes from Streptomyces fulvoviridis.

Carbapenem non-producing mutants were isolated from Streptomyces fulvoviridis and divided into six cosynthesis groups. By using one of the mutants as the host and plasmid pIJ385 as the vector, we cloned carbapenem biosynthetic genes from the parental S. fulvoviridis strain. A cloned 6-kb DNA fragment complemented the defects of three mutants each of which had a mutation in different genes. Southern blot hybridization using the cloned 6-kb fragment as probe showed the presence of the nucleotide sequences homologous to the probe in other carbapenem-producing Streptomyces spp. In addition, Streptomyces griseus, a carbapenem non-producer, possessed the sequence homologous to the probe and showed co-synthesis phenomena with some of the carbapenem non-producing mutants of S. fulvoviridis.

Anti-Bacterial Agents↗
PubMed1989

Family study and frequency of blood group with strong B transferase accompanied by decreased A and H antigens.

Subgroups of type A blood, named A1, A2, and A1-A2 intermediate (Aint), are specifically characterized by their peculiar A alleles and have their own A1-, A2- or Aint-forms of alpha-N-acetyl-D-galactosaminyltransferase (A-transferase). It is known, however, that certain type A2B persons exhibit A1-transferase. The reason may be an unusual alpha-galactosyltransferase (B-transferase). This strong B-transferase competes with A-transferase for the substrate, H antigen, so as to decrease the A and H antigens on the red cells. We studied this blood group over three generations and found that the strong B-transferase is, in fact, inherited with the B gene and is dominant over normal B-transferase. In AB blood groups in Tokyo, the frequency of people with a strong B-transferase is 5% for A1B and 22% for A2B. This enzyme does not always cause weak H or A antigens.

ABO Blood-Group System↗
PubMed1989

Identifying weak signals in the presence of noise: a new method of locating potential ligand contact residues in immunoglobulin-related molecules.

We develop and apply a new method for estimating the locations of hypervariable residues in immunoglobulin-related molecules. The method differs from the standard introduced by Wu and Kabat in two essential ways: (1) we take explicit account of the type of substitution at a given position, rather than just the total number of substitutions, and (2) we use an explicit statistical decision criterion for classifying a site into either the complementarity determining or framework category. Simulations indicate that the method is reliable with relatively little data, approximately 5% of the sites being misclassified when 10 sequences are aligned. The method is applied to immunoglobulin light chains and to class 1 and class 2 products of the major histocompatibility complex.

Filtration↗
PubMed1989

The role of sinusoidal stenoses in portal hypertension of liver cirrhosis.

To investigate the significance of sinusoidal stenoses in portal hypertension, liver cirrhosis was produced by feeding a choline-deficient diet for 6 months in rats, and hepatic haemodynamics were examined in the cirrhotic rats before and after feeding ordinary rat pellets for another 2 months. Feeding ordinary rat pellets led to the disappearance of fat droplets accumulated in the hepatocytes, normalization of the size of the swollen hepatocytes, and recovery from sinusoidal stenoses. As a result, increased sinusoidal vascular resistance and elevated portal vein pressure were reduced markedly, and clinical signs of portal hypertension, ascites and collateral blood circulation around the liver improved prominently. These facts suggest that sinusoidal stenoses lead to an increase in hepatic vascular resistance and portal hypertension.

Angiography↗
PubMed1989

Effects of acetylcholine on thyrotropin-releasing hormone release from the rat caecum in vitro.

Effects of acetylcholine on the release of thyrotropin-releasing hormone (TRH) from the rat caecum in vitro were studied. The rat caecum was incubated in medium 199 with 1.0 mg/ml of bacitracin and 100 micrograms/ml of ascorbic acid (pH 7.4) (medium). The amount of TRH release into the medium was measured by radioimmunoassay. The immunoreactive TRH (ir-TRH) release from the rat caecum was enhanced significantly in a dose-related manner with the addition of acetylcholine, but not changed with atropine. The stimulatory effect of acetylcholine on ir-TRH release from the rat caecum was blocked with an addition of atropine. Elution profile of acid-methanol-extracted rat caecum on Sephadex G-10 was identical to that of synthetic TRH. The findings suggest that the cholinergic system stimulates TRH release from the rat caecum in vitro.

Acetylcholine↗
PubMed1989

Effects of opioid peptides on thyrotropin-releasing hormone release from the rat caecum in vitro.

Effects of opioid peptides (beta-endorphin, dynorphin (1-13). alpha-neoendorphin, beta-neoendorphin, leucine-enkephalin, methionine-enkephalin) on the release of thyrotropin-releasing hormone (TRH) from the rat caecum were studied in vitro. The rat caecum was incubated in medium 199 with 1.0 mg/ml of bacitracin (pH 7.4) (medium). The amount of TRH release from the rat caecum into the medium was measured by radioimmunoassay. The immunoreactive TRH (ir-TRH) release from the rat caecum was inhibited significantly in a dose-related manner with the addition of opioid peptides. The inhibitory effects of opioid peptides on ir-TRH release from the rat caecum were blocked with an addition of naloxone. The elution profile of acid-methanol-extracts of rat caecum on Sephadex G-10 was identical to that of synthetic TRH. The findings suggest that opioid peptides inhibit TRH release from the rat caecum in vitro.

Animals↗
PubMed1989

Patent omphalomesenteric duct: a case report and review of Japanese literature.

Patent omphalomesenteric duct (umbilical enteric fistula) was diagnosed in a 7-day-old infant. The duct closed spontaneously, but at the age of 4 months the infant was readmitted for a resection of the duct. A review of the literature disclosed that 65 cases of patent omphalomesenteric duct have been reported in Japan. The male/female ratio was 2.8:1. Ten out of 36 infants (27.8%) were premature. Surgery was performed in as many patients as possible--55 out of 59 cases (93.2%). The ducts averaged 3.8 cm in length and 1.1 cm in diameter. Errant gastric mucosa was found in 3 out of 30 cases (10.0%). Prolapse of the ileum was present in 28 out of 53 patients (52.8%)--a relatively high incidence. Ten out of 55 patients died (18.2%); 8 of these had a prolapse of the ileum. In view of the high mortality rate of patients with a prolapse of the ileum and the strong possibility of intestinal obstruction, patent omphalomesenteric ducts should be resected surgically.

Female↗
PubMed1989

Relation of sinusoidal stenoses following hepatocyte swelling to hepatic vascular resistance in experimental liver cirrhosis.

To investigate the significance of sinusoidal stenoses and a decrease in the sinusoidal bed due to hepatic cell swelling as a factor increasing hepatic vascular resistance in liver cirrhosis, hepatic vascular resistance in choline-deficient diet-induced cirrhotic rats was measured by an isolated liver perfusion method. In the cirrhotic rats, the swollen hepatic cells resulting from accumulation of fat droplets narrowed the sinusoids and decreased the sinusoidal bed. Consequently, the hepatic vascular resistance was increased by 2.7 times normal (8.60 +/- 2.32 mm H2O.ml-1.min; controls, 3.13 +/- 0.67 mm H2O.ml-1.min), and portal hypertension was also recognized (188.1 +/- 26.3 mm H2O; controls, 114.2 +/- 12.8 mm H2O). In the cirrhotic rats fed with ordinary rat pellets for 2 months, however, the sinusoidal stenoses and the decreased sinusoidal bed recovered to nearly normal as a result of disappearance of the fat droplets in the hepatic cells. The increased hepatic vascular resistance was decreased to 1.5 times normal (4.68 +/- 0.82 mm H2O.ml-1.min), and the elevated portal vein pressure was reduced (141.5 +/- 17.4 mm H2O). These findings clearly demonstrate that an important factor leading to an increase in hepatic vascular resistance is sinusoidal stenoses and a decrease in the sinusoidal bed resulting from swollen hepatic cells.

Animals↗
PubMed1989

[A case report of Campylobacter fetus subspecies fetus bacteremia].

An unusual case of Campylobacter fetus subspecies fetus bacteremia was presented. A twenty four year old male was admitted to our hospital due to abdominal pain, general malaise, diarrhea, high fever, and hemoptysis. He was alcoholic and fond of eating raw liver. He had a history of partial gastrectomy and disturbance of pancreatic function. He showed pulmonary empyema, pleuritis, thrombophlebitis of lower legs, jaundice, hepatomegaly, diarrhea, pneumothorax, and low T3 low T4 syndrome. C. fetus subsp. fetus was detected from the venus blood and pleural effusion on admission. He was successfully treated by gentamicin, chloramphenicol, and minocycline. This is the fourth case of C. fetus subsp. fetus bacteremia in the Japanese literature. This microanerophilic gram negative curved bacillus has been increasingly associated with human disease and relapsing in nature, so protracted antimicrobial therapy was recommended.

Adult↗
PubMed1989

In vitro and in vivo antibacterial activities of AT-4140, a new broad-spectrum quinolone.

AT-4140, 5-amino-1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-(cis-3,5- dimethyl-1-piperazinyl)-4-oxoquinoline-3-carboxylic acid, showed broad and potent antibacterial activity. Its MICs for 90% of the strains tested were 0.1 to 0.78 micrograms/ml against gram-positive organisms, such as members of the genera Staphylococcus, Streptococcus, and Enterococcus, and 0.0125 to 1.56 micrograms/ml against gram-negative organisms, such as members of the family Enterobacteriaceae and the genera Pseudomonas, Branhamella, Campylobacter, Haemophilus, and Neisseria. Its MICs were 0.025 to 0.78 micrograms/ml against glucose nonfermenters, such as members of the genera Xanthomonas, Acinetobacter, Alcaligenes, Moraxella, Flavobacterium, and Brucella; 0.2 to 0.78 micrograms/ml against anaerobes, such as Clostridium perfringens and Bacteroides fragilis; 0.0125 to 0.05 micrograms/ml against Legionella spp.; 0.0125 to 0.2 micrograms/ml against Mycoplasma spp.; 0.031 to 0.063 micrograms/ml against Chlamydia spp.; and 0.1 to 0.3 micrograms/ml against Mycobacterium spp. The potencies of AT-4140 against gram-negative organisms were comparable to those of ciprofloxacin and higher than those of ofloxacin, enoxacin, and norfloxacin. The potencies of AT-4140 against gram-positive organisms, glucose nonfermenters, anaerobes, Mycoplasma spp., Chlamydia spp., and Mycobacterium spp. were generally higher than those of the quinolones with which AT-4140 was compared. AT-4140 showed good oral efficacy against systemic infections with Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Escherichia coli, and Pseudomonas aeruginosa in mice. Its efficacy was better when a daily dose was given once than when it was given in two doses. Good efficacies of the orally administered drug were also observed in pulmonary, dermal, and urinary tract infection models in mice. The in vivo efficacies of AT-4140 were equal to or better than those of ciprofloxacin, ofloxacin, enoxacin, and norfloxacin.

Animals↗
PubMed1989

Behavior of 3,4-endiol form of 2,3-diketo-gulono-delta-lactone formed from dehydro-L-ascorbic acid in deoxygenated and neutral solution.

The formation of L-ascorbic acid (AsA) was observed when dehydro-L-ascorbic acid (DHA) was dissolved in neutral buffer solutions under N2 bubbling at room temperature. The reduction of DHA was done with the lactonized compound of 2,3-diketo-L-gulonic acid (DKG), that is, the 3,4-endiol form of 2,3-diketo-gulono-delta-lactone (3,4-End DKGL). 3,4-End DKGL was formed from DHA or DKG (yield about 10%) under N2 bubbling in neutral buffer solution (pH 7.2). This material was not stable in neutral or alkaline solutions. 3,4-End DKGL suppressed more strongly the linoleic acid (LA) peroxidation in the medium containing 20% EtOH and 10 mM LA than did AsA. This may suggest the possibility that 3,4-End DKGL reproduces AsA from DHA in physiological status.

2,3-Diketogulonic Acid↗
PubMed1989

[Clinical studies on TMJ arthrosis in young people. A study of dental axis of lower molar teeth].

The subjects were 37 female patients with juvenile TMJ arthrosis (T group) and 27 healthy females (N group) who visited the Dept. of Oral Surgery, Nagoya University Hospital or the Dept. of Dent-Oral Surgery, Nagoya University Branch Hospital. Following evaluations were made: 1) L6 to L7 angle 2) L6 to occlusal plane 3) L7 to occlusal plane 4) L6 to mandibular plane 5) L7 to mandibular plane 6) occlusal plane angle 7) mandibular plane angle Following results were obtained: 1. Significant differences between T group and N group were not seen in the occlusal plane angle. 2. A majority in the T group showed a mesial inclination of the lower second molar. 3. Mandibular plane angle in the T group was larger than that in the N group.

Adolescent↗
PubMed1989

[Therapy against intractable respiratory infections with Pseudomonas aeruginosa].

Patients with diffuse panbronchiolitis (DPB) are frequently affected by Pseudomonas aeruginosa superinfection. To elucidate the predisposing factors of Pseudomonas aeruginosa superinfection in patients with DPB, we analyzed the age of onset, duration of the disease, chest X-ray findings, blood gas levels, lung function, and bacteriological findings. These data were compared with those of patients who had not developed Pseudomonas aeruginosa superinfection. The administration of antibiotics and corticosteroids did not influence the incidence of Pseudomonas aeruginosa superinfection in DPB patients. The patients with long duration, more severe lung function and more deteriorated roentgenological findings developed Pseudomonas aeruginosa superinfection more easily. These infections in the lower respiratory tract significantly affect the prognosis of DPB patients. Using long-term administrations of a new quinolone antibacterial agent against DPB, acute exacerbations were controlled in some patients and the frequency of their admission to hospital was lessened. A multicomponent vaccine raised antibody titers against OEP, elastase, protease and exotoxin in DPB patients. Further clinical investigations are under way in our hospital to confirm the clinical usefulness of the Pseudomonas aeruginosa multicomponent vaccine in DPB from prophylactic and therapeutic points of view.

4-Quinolones↗
PubMed1989

[Clinical evaluation of serum sialyl Lewis X-i (SLX) in diffuse panbronchiolitis].

Clinical comparison of SLX with other tumor-associated antigens such as CA19-9, CA125, and CEA, was made in benign respiratory diseases including diffuse panbronchiolitis (DPB), bronchiectasis (BE), bronchial asthma (BA), and pulmonary emphysema (PE). Sensitivities of each marker (greater than 38.0 U/ml) on DPB were 79.4% in SLX, 68.0% in CA19-1, 46.7% in CA125, and 35.7% in CEA. Serum levels of SLX in DPB and BE were significantly higher than those in BA and PE. There seemed to be no relationship between serum levels of SLX and CRP, ESR, and the volume of sputum. Immunohistochemical studies showed positive staining on the surface of respiratory bronchioles and alveolar walls in DPB and these findings were not observed in normal lung tissues. We consider that the high value of serum levels of SLX in DPB can be explained by these findings.

Aged↗
PubMed1989

[Successful treatment with continuous intravenous theophylline therapy at home for a patient with problems of oral theophylline absorption].

A 56-year-old male with non-atopic bronchial asthma was admitted to our hospital due to status asthmaticus. His asthma attacks could not be controlled by oral and/or inhalation therapy, but only by intravenous theophylline therapy with corticosteroid. A theophylline absorption test was performed on him after over night fasting. 500 mg of theophylline was administered. The maximum serum theophylline concentration was only 4.0 micrograms/ml at 30 minutes and the urinary one was 13.0 micrograms/ml at 360 minutes after starting the test. The threshold level of absorption from the intestinal tract was higher than the usual level in this patient. We conclude that among patients with intractable bronchial asthma there may be some who have problems with orally administered theophylline. Continuous theophylline therapy at home is recommended for such intractable asthmatics.

Administration, Oral↗