Biomedical subjects

A Ozawa

Publications and source records attributed to A Ozawa.

At least 19 recordsLinked to original sources

PubMed2006

Vanishing N = 20 shell gap: study of excited states in (27,28)Ne.

This Letter reports on the (1)H((28)Ne, (28)Ne) and (1)H((28)Ne, (27)Ne) reactions studied at intermediate energy using a liquid hydrogen target. From the cross section populating the first 2(+) excited state of (28)Ne, and using the previously determined BE(2) value, the neutron quadrupole transition matrix element has been calculated to be M(n)=13.8 +/- 3.7 fm(2). In the neutron knockout reaction, two low-lying excited states were populated in (27)Ne. Only one of them can be interpreted by the sd shell model while the additional state may intrude from the fp shell. These experimental observations are consistent with the presence of fp shell configurations at low excitation energy in (27,28)Ne nuclei caused by a vanishing N=20 shell gap at Z=10.

Journal Article↗

PubMed2006

Assignment of 101 genes localized in HSA10 to a swine RH (IMpRH) map to generate a dense human-swine comparative map.

Economically important traits such as growth and backfat in pigs have been shown to be influenced by genes in swine chromosome (SSC) 10q12-->qter corresponding to human chromosome (HSA) 10p. However, since gene information in the swine chromosomal region was limited, we attempted to generate a dense comparative map between SSC10 and HSA10 by mapping the 115 genes of HSA10 to a swine RH map (IMpRH map). In the mapping ten genes were assigned to SSC10, 88 to SSC14, and one to SSC3. One gene was suggested to link to SSC3, and another to SSC9. The correspondences between HSA10 and SSC10 and between HSA10 and SSC14 were essentially consistent with the observations obtained from bi/uni-directional chromosome painting or other results. This study further indicated that a large number of intrachromosomal rearrangements occurred in the synteny-conserved regions following species separation.

Animals↗

PubMed2004

Shell structure of the near-dripline nucleus 23O.

Breakup reactions were used to study the ground-state configuration of the neutron-rich isotope 23O. The 22O fragments produced in one-nucleon removal from 23O at 938 MeV/nucleon in a carbon target were detected in coincidence with deexciting gamma rays. The widths of the longitudinal momentum distributions of the 22O fragments and the one-neutron removal cross sections were interpreted in the framework of a simple theoretical model which favors the assignment of Ipi = 1/2+ to the 23O ground state.

Journal Article↗

PubMed2003

Coulomb dissociation of 8B and the low-energy cross section of the 7Be(p,gamma)8B solar fusion reaction.

An exclusive measurement of the Coulomb breakup of 8B into 7Be+p at 254A MeV allowed the study of the angular correlations of the breakup particles. These correlations demonstrate clearly that E1 multipolarity dominates and that E2 multipolarity can be neglected. By using a simple single-particle model for 8B and treating the breakup in first-order perturbation theory, we extract a zero-energy S factor of S17(0)=18.6+/-1.2+/-1.0 eV b, where the first error is experimental and the second one reflects the theoretical uncertainty in the extrapolation.

Journal Article↗

PubMed2003

Therapeutic guidelines for the treatment of generalized pustular psoriasis (GPP) based on a proposed classification of disease severity.

Generalized pustular psoriasis (GPP) is a rare but notoriously recalcitrant cutaneous diseases. Therefore, there have been few reports of more than ten patients with GPP who were treated at the same institution. The severity of this disease and its response to each therapeutic modality vary among patients. In some GPP is life-threatening, but in others it may show a benign, chronic course for a long period of time. Before starting treatment, a knowledge of the therapeutic efficacy and side effects of each drug used in the treatment of GPP is necessary. In our multicenter study, we compared the effectiveness of and adverse reactions to several systemically administered drugs. Following the development of a unique classification of the disease severity based on scoring the clinical symptoms and the laboratory findings, we propose here therapeutic guidelines for the treatment of GPP.

Humans↗

PubMed2003

Experimental evidence for the existence of 7H and for a specific structure of 8He.

Experimental search for the superheavy 7H isotope was performed in the reaction p(8He,pp)7H with the 8He beam at 61.3A MeV. The evidence for existence of the 7H state near the t+4n threshold was obtained. In the same experiment, the p(8He,t) reaction populating the ground and excited 2(+) state of 6He was investigated. The obtained results argue on a specific structure of the 8He ground state containing the 6He subsystem in the excited 2(+) state with a large weight.

Journal Article↗

PubMed2002

Momentum distribution of 15B fragments from the breakup of 17B.

The two-neutron removal cross section (sigma(-2n)) and the longitudinal momentum distribution of 15B fragments from the breakup of 17B on 9Be were measured at 70A MeV. The distribution in the projectile rest frame is characterized by a FWHM of 80+/-10 MeV/c for 15B. The sigma(-2n) is found to be 0.22+/-0.05 b. A Glauber-type analysis of the data provides clear evidence of a two-neutron halo structure in 17B.

Journal Article↗

PubMed2002

Corneodesmosin DNA polymorphisms in MHC haplotypes and Japanese patients with psoriasis.

In order to examine the relationship between corneodesmosin (CDSN) and psoriasis we have determined the presence of CDSN polymorphisms by DNA sequencing in (a) nine B-LCL cell lines of major histocompatibility complex ancestral haplotypes known to be associated with psoriasis vulgaris including 13.1AH, 46.1AH, 46.2 and 57.1AH, and in (b) a group of 267 unrelated individuals comprising Japanese psoriasis patients (n = 101) and Japanese subjects without the disease (n = 166). Three novel CDSN gene sequences were identified. In addition, we have classified the 18 alleles into seven main groups based on phylogeny of non-synonymous substitutions. However, we have found no statistically significant differences between the patients and the unaffected individuals in any of these groups. These findings indicate that CDSN is not a major psoriasis susceptibility gene.

Alleles↗

PubMed2001

Isolation and characterization of the rat prolactin-releasing peptide gene: multiple TATA boxes in the promoter region.

The prolactin-releasing peptide (PrRP) gene is a novel bioactive peptide expressed in very restricted regions in the brain. To explore the molecular mechanism of PrRP gene expression, we cloned and characterized the gene and its promoter region. The gene spans approximately 2.4 kb and contains three exons and two introns. 3'RACE analysis showed that a polyadenylation signal 103 bp downstream from the stop codon was functional. Primer extension analysis indicated three transcriptional start sites (TSSs) 92, 199, and 325 bp upstream from the translational start site. Interestingly, in addition to the putative binding sites for SP1-1, AP-2, and Oct-2A, three characteristic TATA boxes were identified close to these TSSs. Transient transfection study using a series of deletion mutants revealed that the middle TATA box is important for the promoter activity. Furthermore, the cloned 1.6 kb promoter region was active only in neuron- and pituitary-derived cell lines, and the promoter region -1600 approximately -800 bp worked as a negative regulatory element. We demonstrated for the first time, the genomic organization and promoter function of the PrRP gene, and this knowledge will facilitate elucidation of transcriptional control of the PrRP gene.

3' Untranslated Regions↗

PubMed2001

Congenital giant aneurysm of the left atrial appendage mimicking pericardial absence case report.

A 25-year-old man was found to have an abnormal cardiac contour on a chest radiograph, and was referred. Transesophageal echocardiography suggested herniation of the left atrial appendage (LAA) through a gap in the pericardium, and magnetic resonance imaging indicated congenital partial absence of the pericardium. Cardiac dysfunction was caused by compression from the enlarged left atrium and thrombi were thought to be present in the appendage, so surgery was performed. The intraoperative diagnosis was congenital LAA aneurysm. Although distinguishing between congenital LAA aneurysm and congenital absence of the pericardium is reported to be possible with magnetic resonance imaging, we were unable to so in this case.

Adult↗

PubMed2001

Effects of heat exposure on adrenergic modulation of insulin and glucagon secretion in sheep.

The effects of heat exposure on the adrenergic modulation of pancreatic secretion were investigated. Five ewes fed at maintenance level (ME base) were housed in thermoneutral (TN; 20 degrees C) and hot (30 degrees C) environments. Heat exposure caused an increase in respiration rate and a slightly higher rectal temperature, and decreases in basal insulin and glucose concentrations. Infusions of saline plus epinephrine caused increases in glucagon and glucose concentrations, and no significant change in insulin secretion. Phentolamine (an adrenergic alpha-antagonist) plus epinephrine augmented insulin secretion; however, this insulin secretory response was inhibited by heat exposure. Propranolol (a beta-antagonist) plus epinephrine produced a slight decrease in insulin secretion in the TN environment, whereas no effect was observed during heat exposure. While glucagon secretion through alpha-adrenergic stimulation was not affected by heat exposure, homeostatic signals controlling insulin release seemed to be affected during heat exposure. We thus hypothesised that insulin concentration is decreased in sheep fed at maintenance level in hot environments, and that this response is mediated in part by a modulation of beta-adrenergic function.

Adrenergic alpha-Antagonists↗

PubMed2001

Tsutsugamushi disease in Kanagawa Prefecture, Japan: clinical report of two cases and survey of other incidences in 1998.

Tsutsugamushi disease is characterized by the early appearance of a black crust at the bitten area and the subsequent development of macular or macropapular rush on the whole body with high fever. While treatment with tetracycline derivatives and chloramphenicols is effective, delayed diagnosis or inappropriate treatment will lead to fatality. In this report, we describe two typical cases of tsutsugamushi disease and discuss other incidences in Kanagawa Prefecture, Japan, in 1998. One of the present two patients was diagnosed to be a case of the new type by Kawasaki strain of Rickettsia tsutsugamushi, while responsible strain was not identified for the other case. Since the disease is spreading widely even to suburban areas, we emphasize the need to consider the possible diagnosis of tsutsugamushi disease in patients with generalized eruption and high fever.

Anti-Bacterial Agents↗

PubMed2000

New magic number, N = 16, near the neutron drip line

We have surveyed the neutron separation energies (S(n)) and the interaction cross sections (sigma(I)) for the neutron-rich p-sd and the sd shell region. Very recently, both measurements reached up to the neutron drip line, or close to the drip line, for nuclei of Z</=8. A neutron-number dependence of S(n) shows clear breaks at N = 16 near the neutron drip line (T(Z)>/=3), which shows the creation of a new magic number. A neutron-number dependence of sigma(I) shows a large increase of sigma(I) for N = 15, which supports the new magic number. The origin of the new magic number is also discussed.

Journal Article↗

PubMed2000

Comparative organization of cattle chromosome 5 revealed by comparative mapping by annotation and sequence similarity and radiation hybrid mapping.

A whole genome cattle-hamster radiation hybrid cell panel was used to construct a map of 54 markers located on bovine chromosome 5 (BTA5). Of the 54 markers, 34 are microsatellites selected from the cattle linkage map and 20 are genes. Among the 20 mapped genes, 10 are new assignments that were made by using the comparative mapping by annotation and sequence similarity strategy. A LOD-3 radiation hybrid framework map consisting of 21 markers was constructed. The relatively low retention frequency of markers on this chromosome (19%) prevented unambiguous ordering of the other 33 markers. The length of the map is 398.7 cR, corresponding to a ratio of approximately 2.8 cR(5,000)/cM. Type I genes were binned for comparison of gene order among cattle, humans, and mice. Multiple internal rearrangements within conserved syntenic groups were apparent upon comparison of gene order on BTA5 and HSA12 and HSA22. A similarly high number of rearrangements were observed between BTA5 and MMU6, MMU10, and MMU15. The detailed comparative map of BTA5 should facilitate identification of genes affecting economically important traits that have been mapped to this chromosome and should contribute to our understanding of mammalian chromosome evolution.

Animals↗

PubMed2000

Expression of thyrotropin-releasing hormone (TRH) receptor subtype 1 in mouse pancreatic islets and HIT-T15, an insulin-secreting clonal beta cell line.

Thyrotropin-releasing hormone (TRH), originally isolated as a hypothalamic hormone, has been reported to be present and released from the pancreatic beta cells, affecting pancreatic functions. However, it still remains unclear whether TRH receptor is expressed in the pancreas. In the present study, we characterized TRH receptors (TRHR) in mouse pancreatic islets and HIT-T15 cells, a hamster clonal beta cell line. RT-PCR study showed significant expression of TRHR subtype 1 (TRHR1) mRNA in both mouse pancreatic islets and HIT-T15 (HIT) cells. In contrast, there was no expression of TRHR2 mRNA, a novel subtype of TRHR which is expressed predominantly in the central nervous system. Sequencing analysis demonstrated that TRHR1 of the islets was identical to that in the pituitary, and cloned hamster TRHR1 shared 93.3 % homology with that of the mouse at the nucleic acid level. Northern blot analysis of TRHR 1 mRNA in HIT-T15 cells showed a single strong hybridization signal approximately 3.7 kb in length. Furthermore, Scatchard plot analysis in HIT-T15 cells revealed that the Kd value for MeTRH was 0.63 nM. Significant elevation of intracellular calcium concentration was observed in response to as little as 10 nM TRH , and this was not affected by removal of extracellular calcium. This is the first description indicating the presence of functional TRH receptor subtype 1 in the pancreatic beta cells, and our observations suggested the regulation of pancreatic function by TRH through autocrine or paracrine mechanisms.

Amino Acid Sequence↗

PubMed2000

Apoptosis and its regulation in flat-type early colorectal carcinoma: comparison with that in polypoid-type early colorectal carcinoma.

PURPOSE: The aim of this study was to investigate the relationship among apoptotic cell death, proliferative activity, and the expression of apoptosis-regulating proteins (p53, p21 (WAF1/CIP1), and bax) in flat-type early colorectal carcinoma and to compare these factors with those in polypoid-type early colorectal carcinoma. METHODS: Formalin-fixed, paraffin-embedded tissues of 11 flat-type early colorectal carcinomas and 17 polypoid-type early carcinomas were studied. The histologic diagnosis was either well-differentiated adenocarcinoma or carcinoma in adenoma, and the depth of invasion was limited to mucosa or submucosa. Apoptotic cells were detected by terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling method, and proliferative activity was determined by Ki-67 immunohistochemistry using monoclonal antibody MIB-1. Apoptosis-regulating proteins were determined by immunohistochemistry using antibody DO-7 (p53), Cip1 (p21 (WAF1/CIP1)), and Bax (bax). RESULTS: There was no significant difference in terminal deoxynucleotide transferase-mediated deoxy-uridine triphosphate-biotin nick end-labeling index between flat-type early colorectal carcinoma and polypoid-type early carcinoma, at 1.9 vs. 1.1, respectively. In flat-type carcinoma terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling index in the p53 protein overexpression group was significantly smaller than that in the p53 protein-negative group (P < 0.05). The Ki-67 labeling index/terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling index ratio in the p53 protein overexpression group was significantly higher than that in the p53 protein-negative group (P < 0.05). In polypoid-type carcinoma, the terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling index and Ki67/terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling index ratio showed no significant difference between the p53 protein overexpression group and p53 protein-negative group. CONCLUSION: p53-dependent apoptosis may contribute to the development of flat-type early colorectal carcinoma. Apoptosis and its regulation in flat-type early colorectal carcinoma may differ from those in polypoid-type carcinoma.

Apoptosis↗

PubMed2000

Predictive factors for detecting colorectal carcinomas in surveillance colonoscopy after colorectal cancer surgery.

PURPOSE: The aim of this study was to identify the high-risk groups for metachronous colorectal carcinoma among patients who undergo colorectal cancer surgery. METHODS: Three hundred forty-one patients undergoing colorectal cancer surgery who had undergone surveillance colonoscopy at least twice during a period of more than three years were analyzed. A metachronous colorectal carcinoma was defined as a new colorectal carcinoma detected by surveillance colonoscopy after surgery. RESULTS: Surveillance colonoscopy was performed 4.6 times per patient during an average of 6.2 years. Twenty-two metachronous colorectal carcinomas in 19 patients were detected, and 14 (64 percent) of 22 were detected within five years of surgery. The cumulative incidence of developing colorectal carcinomas during a five-year period was 5.3 percent. Seventeen (77 percent) of 22 carcinomas were 10 mm or less in size. Ten (71 percent) of the 14 carcinomas in early stages showed a flat appearance. Univariate analysis showed that extracolonic malignancy, coexistence of adenoma, and synchronous multiple colorectal carcinoma were significant predictive factors for detecting colorectal carcinomas in surveillance colonoscopy and that family history of colorectal carcinoma was a possible predictive factor. Multivariate analysis performed with Cox proportional hazards regression model showed that extracolonic malignancy and the coexistence of adenoma were significant predictive factors. CONCLUSION: We recommend that patients with the above predictive factors receive surveillance colonoscopy meticulously and regularly.

Adult↗

PubMed2000

Cytokine and hormonal responses in laparoscopic-assisted colectomy and conventional open colectomy.

Interleukin-6 (IL-6) is an important mediator of the acute phase response and a sensitive marker of tissue damage. This study was conducted to investigate the fluctuation of serum cytokine and hormonal levels during the perioperative period after laparoscopic-assisted colectomy (LAC), and the data were compared with those after conventional open colectomy (OPEN). The subjects comprised eight patients who underwent OPEN and eight who underwent LAC. Blood samples were obtained by peripheral vein puncture before the induction of anesthesia, then 2, 4, 6, 8, 24, 48, and 72 h after skin incision to measure the levels of serum IL-6, adrenocorticotropic hormone (ACTH), cortisol, and antidiuretic hormone (ADH). The level of serum IL-6 increased significantly during the perioperative course in both groups; however, the level 4 h after the commencement of surgery and the peak level were significantly lower in the LAC group than in the OPEN group (P < 0.05). Plasma ACTH, cortisol, and ADH rapidly increased in both groups, but there was no significant difference between them. The IL-6 levels in collected ascites samples were not significantly different between the two groups. The changes in serum IL-6 levels indicate that LAC is less invasive than conventional open colectomy. These findings corresponded well with the clinical courses of the patients who underwent the two types of operations.

Adrenocorticotropic Hormone↗