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Biomedical subjects

K Kino

Publications and source records attributed to K Kino.

At least 19 recordsLinked to original sources

Identification of repair enzymes for 5-formyluracil in DNA. Nth, Nei, and MutM proteins of Escherichia coli.

5-Formyluracil (5-foU) is a potentially mutagenic lesion of thymine produced in DNA by ionizing radiation and various chemical oxidants. Although 5-foU has been reported to be removed from DNA by Escherichia coli AlkA protein in vitro, its repair mechanisms are not fully understood. In this study, we used the borohydride trapping assay to detect and characterize repair activities for 5-foU in E. coli extracts with site-specifically designed oligonucleotides containing a 5-foU at defined sites. The trapping assay revealed that there are three kinds of proteins that form covalent complexes with the 5-foU-containing oligonucleotides. Extracts from strains defective in the nth, nei, or mutM gene lacked one of the proteins. All of the trapped complexes were completely lost in extracts from the nth nei mutM triple mutant. The introduction of a plasmid carrying the nth, nei, or mutM gene into the E. coli triple mutant restored the formation of the corresponding protein-DNA complex. Purified Nth, Nei, and MutM proteins were trapped by the 5-foU-containing oligonucleotide to form the complex in the presence of NaBH(4). Furthermore, the purified Nth, Nei, and MutM proteins efficiently cleaved the oligonucleotide at the 5-foU site. In addition, 5-foU was site-specifically incorporated into plasmid pSVK3, and the resulting plasmid was replicated in E. coli. The mutation frequency of the plasmid was significantly increased in the E. coli nth nei mutM alkA mutant, compared with the wild-type and alkA strains. From these results it is concluded that the Nth, Nei, and MutM proteins are involved in the repair pathways for 5-foU that serve to avoid mutations in E. coli.

Borohydrides↗

Purification, identification, and cDNA cloning of Jun a 2, the second major allergen of mountain cedar pollen.

The second major allergen of Juniperus ashei (mountain cedar) pollen, Jun a 2, has been purified and its cDNA cloned. The purified protein has a molecular mass of 43 kDa and its N-terminal 9-residue amino acid sequence is highly homologous to those of Cry j 2 and Cha o 2, the second major allergen of Cryptomeria japonica and Chamaecyparis obtusa pollen, respectively. cDNA clones encoding Jun a 2 were isolated after PCR based amplification, and their nucleotide sequences were determined. The cDNA contains an open reading frame of 507 amino acid residues, and encodes a putative 54-residue signal sequence and a 453-residue intermediate, which releases a C-terminal fragment upon maturation. Three possible N-linked glycosylation sites and 20 cystein-residues are found in the deduced amino acid sequence. The amino acid sequence of Jun a 2 shows 70.7 and 82.0% identity with those of Cry j 2 and Cha o 2, respectively. Immunological observations that IgE antibodies in sera of Japanese pollinosis patients bind not only to Cry j 2 and Cha o 2 but also to Jun a 2 strongly suggest that Jun a 2 is an allergen of mountain cedar pollen, and that allergenic epitopes of these three allergens are similar.

Allergens↗

Out of plane measurements of the decay neutron from the giant resonance in the 12C(e,e(')n)11C reaction

Out of plane measurements of the angular correlations for the 12C(e, e(')n) reaction have been performed for the first time in the giant resonance region. The cross sections were directly separated into the longitudinal and transverse, longitudinal-transverse, and transverse-transverse components. The cross section at the peak of the giant resonance ( omega = 22.5 MeV) has been found to be almost all longitudinal. It was reproduced by the multipole expansion with E0 and E2 components besides E1. The longitudinal-transverse component might have a maximum around 24 MeV. The transverse-transverse component is very small over the giant resonance.

Journal Article↗

Single-stage repair of aortic coarctation with ventricular septal defect using isolated cerebral and myocardial perfusion.

OBJECTIVE: To avoid hypothermic circulatory arrest, we have repaired aortic coarctation with ventricular septal defect (VSD) in a one-stage procedure using an isolated cerebral and myocardial perfusion technique, and retrospectively compared this novel approach to the conventional two-stage approach. METHODS: Between October 1991 and February 1999, 24 infants, aged 4-137 days (median, 27 days) and weighing 1.7-4.3 kg (median, 3.0 kg), underwent the repair of aortic coarctation with VSD either in one (group I, n=11) or two stages (group II, n=13). In Group I, an arterial cannula for cardiopulmonary bypass was inserted into the ascending aorta in six patients with coarctation only, or into a polytetrafluoroethylene (PTFE) graft which was anastomosed to the innominate artery in the remaining five who had hypoplastic arches. A cross-clamp was placed between the innominate and left carotid arteries. The bypass flow was reduced to 30-50% of full flow at 28 degrees C, thereby maintaining a radial artery pressure of 30-45 mmHg. At this point, the aortic coarctation was repaired by an end-to-end arch anastomosis, while maintaining brain perfusion and with the heart still beating. In five patients with hypoplastic aortic arches, the innominate artery proximal to the graft was then secured down and the arch anastomosis was extended to the distal ascending aorta, while providing isolated cerebral perfusion and cardioplegic arrest. After arch reconstruction was performed, the clamp was moved onto the ascending aorta, and the VSD was closed with systemic perfusion. In contrast, for group II patients, coarctation repairs were performed through a posterolateral approach, and existing VSDs were closed as secondary procedures. RESULTS: The mean isolated cerebral and myocardial perfusion time for group I was 13 min (range, 7-20 min). The myocardial ischemic time did not differ between groups I and II (43+/-4 vs. 42+/-5 min, not significant). There were no hospital mortalities or neurological complications in either group, but one late death in each group. CONCLUSION: Single-stage repair of aortic coarctation with VSD does not increase myocardial ischemic time compared to the traditional two-stage approach. The isolated cerebral and myocardial perfusion technique may offer substantial brain and myocardial protection during aortic arch reconstruction.

Aortic Coarctation↗

Differential diagnosis of calcium pyrophosphate dihydrate deposition of the temporomandibular joint.

Calcium pyrophosphate dihydrate (CPPD) deposition disease (pseudogout) of the temporomandibular joint (TMJ) is rare. It is characterized by the presence of crystal deposits that are birefringent under polarized light. Although these crystals are characteristically weakly birefringent, some other crystals such as those of calcium oxalate, synthetic steroids, and ethylenediaminetetraacetic acid are also birefringent. The differential diagnosis should therefore be based on a quantitative analysis of crystals or observation of the crystal structure in calcified sections. We present a case of CPPD deposition disease of the TMJ and report on the value of such an analysis to substantiate the diagnosis.

Biopsy↗

Autosomal albino chicken mutation (ca/ca) deletes hexanucleotide (-deltaGACTGG817) at a copper-binding site of the tyrosinase gene.

We compared tyrosinase cDNA sequences from a line of autosomal albino and Black Silky chickens isolated from cultured melanocytes by reverse transcription-polymerase chain reaction (RT-PCR). Both sources produce a single DNA fragment of predicted normal tyrosinase size. Direct sequencing of the PCR product showed three mutated sites in the tyrosinase gene of the albino chicken. Two silent point mutations and a deletion of six nucleotides (-deltaGACTGG) at 817 bp in the tyrosinase cDNA sequence were observed when compared with the White Leghorn and Black Silky cDNA sequences. The deduced albino chicken tyrosinase protein lacks two amino acids, aspartic acid and tryptophan. The position of these amino acids is consistent with one of the potential copper-binding sites that should be indispensable for function of the enzyme. We speculate that the six-base deletion is responsible for the inactive tyrosinase in this line of albino chickens.

Amino Acid Sequence↗

Hepatocellular carcinoma arising in an elderly male with primary biliary cirrhosis.

We report the case of an elderly male with asymptomatic primary biliary cirrhosis (PBC) who developed a hepatocellular carcinoma (HCC). The 89-year-old man, who was otherwise healthy, was admitted for investigation of mild hepatic dysfunction, which had been detected during a routine physical check-up. Serum chemistry, positive anti-mitochondrial antibody (M2) and liver biopsy results led to a diagnosis of PBC. Three years later, at age 92, computed tomography (CT) and ultrasound scans of his abdomen revealed a large hepatic tumour, which was confirmed on liver biopsy to be HCC. The tumour ruptured 3 months after diagnosis and the patient was successfully stabilized by coil embolization of his right hepatic artery. We believe that, to date, this is the oldest reported patient to have had interventional radiology for the management of HCC.

Aged↗

[Japanese anger expression styles and their interpersonal influence].

The purpose of the present study was to investigate Japanese anger expression styles and their influence on interpersonal relationships. In the initial study, 239 undergraduates were asked to complete a questionnaire which assessed seven distinct anger expression styles. The results indicated that the participants most often employed three anger expression styles including hyojo-kucho (nonverbal), tohmawashi (implicit), and itsumodori (none). In the second study, 162 undergraduates were asked to watch these three anger expression styles portrayed on videotape. Participants rated the degree to which the actor in the videotape felt angry and their impressions toward male or female actors in either higher, lower, or equal status, same-sex situations. The findings indicated that the effect on interpersonal relationships varied across the three different expression styles. This study has important implications for understanding Japanese anger expression in interpersonal, and perhaps cross-cultural, relationships.

Adult↗

[Delayed sternal closure after open heart surgery in neonates and early infants].

Between November 1992 and February 1996, 84 patients (less than 3 months of age) underwent open heart surgery. Among 76 patients except 8 who required mechanical circulatory support, the sternum was left open. The indication of open sternotomy was hypoplastic left heart syndrome in 14 patients and unstable hemodynamics in 4 patients. Three patients died before delayed sternal closure. Delayed sternal closure was carried out in 15 patients with a mean of 4.7 days postoperatively. By the time of sternal closure, blood pressure, left atrial pressure and respiratory parameters improved and inotropics were reduced with the minus fluid balance. One patient died of sepsis 4 days after delayed sternal closure. Delayed sternal closure was effective modality to neonates or early infants after complex open heart surgery.

Cardiac Surgical Procedures↗

Purification, identification, and cDNA cloning of Cha o 2, the second major allergen of Japanese cypress pollen.

The second major allergen of Chamaecyparis obtusa (Japanese cypress) pollen, Cha o 2, has been purified and its cDNA cloned. Of patients with pollinosis caused by C. obtusa, 82.5% produce IgE antibodies which react with purified Cha o 2. The purified protein has a molecular mass of 46 kDa and its 12 N-terminal amino acid sequence displays a high homology with that of Cry j 2, the second major allergen of Cryptomeria japonica pollen. cDNA clones coding for Cha o 2 have been isolated using Cry j 2 cDNA as a probe. Cha o 2 cDNA clones were sequenced and found to code a putative 50-residue signal sequence and a 464-residue mature protein with a molecular weight of 50 kDa. Two possible N-linked glycosylation sites were found in the sequence. The deduced amino acid sequence of Cha o 2 shows 74.3% identity with that of Cry j 2. In its primary structure, Cha o 2 shows significant identity with those of the polygalacturonases of avocado, tomato, and maize as well as Cry j 2.

Allergens↗

Metallic residues as a source of artifacts in magnetic resonance imaging of the temporomandibular joint.

OBJECTIVES: To establish the source of metallic artifacts on postoperative MRI of the temporomandibular joint after arthroplasty. METHODS: An experiment was carried out to evaluate MR artifacts which were thought to have been caused by minute metallic particles deposited at surgery. Four types of cutting instruments were used to cut an extracted tooth: a diamond bur attached to a dental air turbine handpiece, a steel bur and bone bur attached to a dental micromotor handpiece and a bone file. The tooth fragments were collected in plastic centrifuge tubes in water. These samples were evaluated with six MR sequences. RESULTS: MR artifacts were clearly demonstrated in samples using the bone bur and the bone file but not the diamond and steel burs. CONCLUSIONS: The artifacts seen on postoperative MRI were derived from minute metal particles from the bone bur or file used for condylar arthroplasty. Metal artifacts should be considered when interpreting postoperative MR images.

Adult↗

Replication in vitro and cleavage by restriction endonuclease of 5-formyluracil- and 5-hydroxymethyluracil-containing oligonucleotides.

PURPOSE: To investigate the biological consequences of 5-formyluracil (5-foU) and 5-hydroxymethyluracil (5-hmU). MATERIALS AND METHOD: The authors constructed 22-mer oligonucleotides containing a 5-foU or 5-hmU residue at the same sites. The effects of such modifications on the ability to serve as a template for DNA polymerase and on the cleavage by sequence-specific restriction endonuclease were examined. RESULTS: The Klenow fragment of DNA polymerase I and Thermus thermophilus DNA polymerase read through the sites of 5-foU and 5-hmU in the templates. 5-FoU directed the incorporation of dCMP in addition to dAMP opposite the lesion during DNA synthesis. The DNA polymerases incorporated only dAMP opposite the 5-hmU. The substitution of thymine by 5-foU within the recognition site of the restriction endonucleases HincII and SalI inhibited or prevented the cleavage by the enzymes, whereas the enzymes cleaved the 5-hmU-containing oligonucleotides at the same rate as the T-containing oligonucleotides. CONCLUSIONS: These results indicated that the 5-foU-A base pair is less stable than the T-A base pair and that 5-foU can form a base pair with C in addition to A. It was also demonstrated that the oxidation of thymine to 5-hmU does not result in substantial deterioration.

Animals↗

Early carcinoma of the distal second part of the duodenum treated by wedge resection.

A case of early carcinoma of the distal second part of the duodenum, in a 74-year-old man, is presented. Endoscopic retrograde cholangiopancreatography was performed for diagnosis of a common bile duct stone. During this procedure, small elevated lesions were found incidentally in the distal second part of the duodenum, and the histologic examination of a biopsy specimen showed adenocarcinoma. The lesions were removed by wedge resection, and pathologic examination revealed duodenal carcinoma limited to the lamina propria. Although carcinoma of the duodenum, other than of the ampulla of Vater region, is very rare, it is sometimes possible to detect asymptomatic early tumors. However, this requires careful observation of the entire duodenal mucosa, including that of the distal duodenum, at duodenoscopy.

Adenocarcinoma↗

Peptide specificity, HLA class II restriction, and T-cell subsets of the T-cell clones specific to either Cry j 1 or Cry j 2, the major allergens of Japanese cedar (Cryptomeria japonica) pollen.

BACKGROUND: Cry j 1 and Cry j 2 are thought to be the major allergens of Japanese cedar pollen. HLA class II types capable of presenting T-cell epitopes in both allergens and their role in induction of T-cell subsets are not well known. METHODS: CD4+ T (Th)-cell clones (TCCs) specific to either Cry j 1 or Cry j 2 were generated. HLA class II restrictions were determined by their reactivity to the T-cell epitope in the presence of antigen presenting cells sharing matched types. Interleukin (IL)-2, interferon-gamma, IL-4, and IL-5 contents in the supernatants of TCCs were estimated using enzyme immunoassay. RESULTS: Peripheral blood mononuclear cells (PBMC) from patients induced proliferation with 100 microgram/ml Cry j 1 or 3-10 microgram/ml rCry j 2 stimulation. T-cell epitopes in Cry j 1 were presented to Th cells by the gene products of DRA1*01/DRB1*0901, DRA1*01/DRB5*0101, DQA1* 0102/DQB1*0602, and DPA1*01/DPB1*0501; those in Cry j 2 were restricted by DRA1*01/DRB1*0901, DRA1* 01/DRB1*1501, DRA1*01/DRB4*01, DRA1*01/DRB5* 0101, DQA1*0102/DQB1*0602, DPA1*01/DPB1*0201, and DPA1*01 and *0202/DPB1*0501. Type 2-like cells were preferentially induced in Cry j 1 stimulation, while an almost equal number of type 2- and type 1-like cells was induced in rCry j 2. CONCLUSIONS: No clear correlation existed between peptide specificity, HLA class II restriction and induction of Th-cell subsets, suggesting that the requirement of different dose of Cry j 1 or Cry j 2 to induce proliferation in PBMC may lead to distinguishable difference in induction of Th subsets between TCCs specific to Cry j 1 and Cry j 2.

Adult↗

[Large cell carcinoma of the lung with metastasis of the gastric submucosa].

A 66-year-old man was admitted with dyspnea on exertion and an abnormal shadow on chest roentgenogram. Transbronchial biopsy yielded a diagnosis of large cell carcinoma of the lung. His dyspnea improved following irradiation and corticosteroid treatment and one month later, he was admitted again for chemotherapy. Because occult blood in stool was detected, upper gastrointestinal endoscopy was performed. Gastric submucosal large cell carcinoma was diagnosed, and this was considered to be metastatic from the lung. Such cases diagnosed prior to death are rare.

Aged↗

Non-equivalent cooperation between the two nucleotide-binding folds of P-glycoprotein.

To identify the roles of the two nucleotide-binding folds (NBFs) in the function of human P-glycoprotein, a multidrug transporter, we mutated the key lysine residues to methionines and the cysteine residues to alanines in the Walker A (WA) motifs (the core consensus sequence) in the NBFs. We examined the effects of these mutations on N-ethylmaleimide (NEM) and ATP binding, as well as on the vanadate-induced nucleotide trapping with 8-azido-[alpha-32P]ATP. Mutation of the WA lysine or NEM binding cysteine in either of the NBFs blocked vanadate-induced nucleotide trapping of P-glycoprotein. These results suggest that if one NBF is non-functional, there is no ATP hydrolysis even if the other functional NBF contains a bound nucleotide, further indicating the strong cooperation between the two NBFs of P-glycoprotein. However, we found that the effect of NEM modification at one NBF on ATP binding at the other NBF was not equivalent, suggesting a non-equivalency of the role of the two NBFs in P-glycoprotein function.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

T cell epitopes in Japanese cedar (Cryptomeria japonica) pollen allergens: choice of major T cell epitopes in Cry j 1 and Cry j 2 toward design of the peptide-based immunotherapeutics for the management of Japanese cedar pollinosis.

Japanese cedar pollinosis is caused by exposure to Japanese cedar (Cryptomeria japonica) pollen, of which two components, Cry j 1 and Cry j 2, are believed to be the major allergens. T cell lines specific to either Cry j 1 or rCry j 2 were reactive to various portions of each panel of overlapping peptides derived from Cry j 1 or Cry j 2. Two peptides, p211-225 and p108-120, from among six major T cell epitopes identified in Cry j 1 sequence, and three peptides, p182-200, p344-355, and p66-80, from among five in Cry j 2, were chosen to design an artificial polypeptide (named Cry-consensus) based on a difference among the types of the restriction molecules capable of presenting these peptides. After construction of a DNA encoding these peptides in order, Cry-consensus was expressed in Escherichia coli. Five of six T cell epitopes, except for Cry j 2 p344-355, in Cry-consensus were recognized by the T cell clones specific to each peptide. PBMC from allergic patients induced higher proliferation under stimulation from Cry-consensus than individual peptides. Eighty-eight percent of the PBMC (15 of 17) showed proliferation under the Cry-consensus stimulation. Thus, several major T cell epitopes from Cry j 1 and Cry j 2 can be chosen in the design of peptide-based immunotherapeutics for the management of Japanese cedar pollinosis in subjects having various types of HLA class II molecules.

Adult↗