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Biomedical subjects

K Kuroki

Publications and source records attributed to K Kuroki.

16 recordsLinked to original sources
PubMed1992

Multiple metastatic calcifications detected by bone scintigraphy and demonstrated by CT.

Metastatic calcifications according to histopathologic and scintigraphic findings have been well-defined. The authors report a postoperative case of hyperparathyroidism with multiple metastatic calcifications in the lung, kidney, stomach, heart, and vessels that were primarily detected by bone scintigraphy and demonstrated by CT. Tc-99m MDP bone scintigraphy showed a markedly increased accumulation of radioactivity diffusely throughout the lung, left ventricular wall, both kidneys, and the gastric cardia and body. In the lung, plain films showed almost normal lung. CT, however, demonstrated patchy, slightly increased densities in the lung bilaterally. Cardiac CT indicated a considerably increased density of the ventricular myocardium and remarkable calcification in or near the atrioventricular septum or annulus fibrosus. Upper abdominal CT demonstrated increased densities diffusely throughout the gastric mucosa and renal cortex. Only vascular calcifications were depicted by plain films. Using both bone scintigraphy and CT provides accurate information about each lesion and each tissue, allowing precise diagnosis of even a questionable lesion in the early stage of metastatic calcification. Early diagnosis and early therapy offer the best chance for cure or palliative therapy.

Bone and Bones↗
PubMed1990

Epitope mapping of the PreS1 domain of the hepatitis B virus large surface protein.

The large (L) surface glycoprotein of hepatitis B virus is an important component of the virion envelope derived from translation initiation at the 5' end of the PreS1 domain of the surface antigen open reading frame. Since key roles in virion assembly and infectivity have been postulated for this protein, further understanding of its structure and topology is important. To this end we have mapped the epitopes recognized by a panel of monoclonal antibodies specific for this polypeptide by examining their reactivity with a series of deletion mutants of the PreS1 region expressed in cultured cells. On the basis of this and other techniques, the antibodies fall into two groups mapping to two distinct epitopes spanning residues 27-35 and 72-78, respectively. Immunoprecipitation studies indicate that both regions are exposed on the surface of HBV-encoded particles.

Antibodies, Monoclonal↗
PubMed1989

Novel N-terminal amino acid sequence required for retention of a hepatitis B virus glycoprotein in the endoplasmic reticulum.

The preS1 surface glycoprotein of hepatitis B virus is targeted to the endoplasmic reticulum (ER) and is retained in this organelle when expressed in the absence of other viral gene products. The protein is also acylated at its N terminus with myristic acid. Sequences responsible for its ER retention have been identified through examination of mutants bearing lesions in the preS1 coding region. These studies reveal that such sequences map to the N terminus of the molecule, between residues 6 and 19. Molecules in which this region was present remained in the ER; those in which it had been deleted were secreted from the cell. Although all deletions which allowed efficient secretion also impaired acylation of the polypeptide, myristylation alone was not sufficient for ER retention: point mutations which eliminated myristylation did not lead to secretion. These data indicate that an essential element for ER retention resides in a 14-amino-acid sequence that is unrelated to previously described ER retention signals.

Amino Acid Sequence↗
PubMed1989

[Individual growth study of the effects of chin cap force to the mandible].

This study was undertaken to investigate a certain regulation of the chin cap force to a growing human mandible, especially with regard to the effect on the growth amount and timing by means of allometric relation between stature and craniofacial complex. Materials were consisted of roentgencephalograms which had been taken from fifteen Japanese females with skeletal class III malocclusion and records of time length of chin cap use and stature. The results were as follows: 1. Chin cap had a great influence on mandible during the preadolescent and adolescent periods (P less than 0.01). 2. What was most influenced by orthopedic force was intercondylar width, followed by mandibular length, intergonial width, mandibular body length, and ramus height. 3. Restraint of growth was found in mandibular length, mandibular body length, and ramus height, but on the other hand acceleration of growth in intercondylar width and intergonial width was also found. In conclusion, it would be possible to say that if it is used propertly, chin cap therapy can be effective within certain limits for skeletal class III malocclusions in view of restraint and acceleration of mandibular growth.

Cephalometry↗
PubMed1988

Molecular cloning and expression of a gene for a factor which stabilizes formation of inhibitor-mitochondrial ATPase complex from Saccharomyces cerevisiae.

Stabilizing factor, a 9 kDa protein, stabilizes and facilitates formation of the complex between mitochondrial ATP synthase and its intrinsic inhibitor protein. A clone containing the gene encoding the 9 kDa protein was selected from a yeast genomic library to determine the structure of its precursor protein. As deduced from the nucleotide sequence, the precursor of the yeast 9 kDa stabilizing factor contains 86 amino acid residues and has a molecular weight of 10,062. From the predicted sequence we infer that the stabilizing factor precursor contains a presequence of 23 amino acid residues at its amino terminus. We also used S1 mapping to determine the initiation site of transcription under glucose-repressed or derepressed conditions. These experiments suggest that transcription of this gene starts at three different sites and that only one of them is not affected by the presence of glucose.

Adaptor Proteins, Signal Transducing↗
PubMed1986

[Effect of glutaraldehyde on cultured cells--restraining effect on multiplication of L cells].

Glutaraldehyde (GA) was tested for its cytotoxic effect on L cell tissue culture system in comparison with formaldehyde (FA). In the first study, the replanted cells were grown to monolayers on the flattened bases of the culture tubes, and then exposed to the drug. In the second study, the drug was added to the cell suspension just put in the culture tubes. In either case, the cells were kept in contact with the drug at 37 degrees C for 24, 48 or 72 hr, after which time the monolayers were removed and the viable cells in each of the tubes were counted up. The change in the number of viable cells was examined in the various concentrations of the drugs and time intervals of cell-drug contact. Both GA and FA showed relatively slight toxic effect when each concentration was 1 microgram/ml. The cells exposed to 1, 10 micrograms/ml of GA or 1 microgram/ml of FA were able to increase in number, though markedly restrained from their multiplication if compared with the control. GA and FA seriously diminished the viable cells at a concentration of 100 micrograms/ml and 10 micrograms/ml, respectively, and they were so toxic that complete cell death was immediately caused even when the concentration of each drug was at 1000 micrograms/ml. Just replanted cells showed less tolerance to the drug effects than the cells of established monolayers; suppression of cell growth was noted with the concentration of 0.8 microgram/ml and above of either GA or FA, and complete cell death was caused by 58 micrograms/ml of GA and 7.0 micrograms/ml of FA.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldehydes↗
PubMed1985

Topical immunology of nasal allergy and mucosal IgE antibodies.

In the present study, the in vitro tissue-radioallergosorbent test (t-RAST) was performed in two groups of patients: one with perennial attacks of sneezing, serous hypersecretion and nasal congestion, the other with nasal congestion only. The results obtained were compared with those obtained by a series of conventional allergy tests. We then found that t-RAST provided objective data comparable to those obtained with serum-RAST and that the t-RAST is a reliable means of quantitatively detecting specific IgE antibodies in the nasal mucosa. t-RAST is of special value to diagnosticians because it is able to discern unequivocally and easily those patients with localized nasal allergy.

Humans↗
PubMed1985

Lectin histochemistry in a case of ulcerative colitis complicating rectal carcinoma.

The large bowel from a patient with ulcerative colitis complicating a rectal carcinoma was histochemically investigated by using two lectins; Ulex europaeus agglutinin-I (UEA-I) and peanut lectin (PNA). Much UEA-I binding glycoantigen and PNA binding glycoantigen appeared in the carcinoma and dysplastic lesion whereas only a small amount of both antigens was found in the non-dysplastic regenerating epithelium. Consequently, a very sharp contrast between the dysplastic lesion and non-dysplastic regenerating epithelium was demonstrated by the lectin staining.

Adenocarcinoma↗
PubMed1976

Electrocoagulation biopsy of aberrant pancreas of the stomach. A case of aberrant gastric pancreas.

Histopathological diagnosis of submucosal tumors of the stomach has been difficult by conventional examination, e.g. roentgenography, gastroscopy and/or routine biopsy procedure. When endoscopic diagnosis of submucosal tumor is made, surgery is generally performed for tissue biopsy. We have been attempting to avoid such exploratory laparotomy to determine the histologic nature of small asymptomatic submucosal tumors of the stomach by a technic of endoscopic biopsy followed by electrocoagulation. With such a procedure, we have been able to diagnose a case of aberrant pancreas of the stomach. Our experience suggests that this technic is a safe and useful diagnostic tool.

Adult↗