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T Niimi

Publications and source records attributed to T Niimi.

At least 19 recordsLinked to original sources
PubMed2006

Germ-line transformation and RNAi of the ladybird beetle, Harmonia axyridis.

To elucidate the molecular mechanisms underlying the tremendous diversity of insect wing colour patterns, it is imperative to identify and functionally characterize the genes involved in this developmental process. Here we report the first successful germ-line transformation using the transposable element vector piggyBac in the ladybird beetle Harmonia axyridis, which demonstrates typical genetic polymorphism in its wing colour patterns. The transformation efficiency by piggyBac was 3.7% per fertile G(0). We investigated the effectiveness of RNAi in Harmonia by injecting EGFP (enhanced green fluorescent protein) dsRNA into early transgenic EGFP-expressing embryos and observed substantial reduction of EGFP fluorescence in 87.2% of hatched larvae. Application of these new genetic tools to non-model insects such as Harmonia will facilitate the broad understanding of developmental mechanisms and evolutionary processes that are inaccessible using established model systems.

Animals↗
PubMed2005

Extended aortic bypass for atherosclerotic occlusive disease of high abdominal aorta.

We describe a case of acute renal failure caused by extension of an atherosclerotic occlusive process to the suprarenal aorta. A 68-year-old man underwent bypass grafting from the ascending aorta to the femoral arteries using straight and Y-grafts. Additional saphenous vein grafts were placed from the intra-abdominal portion of the graft to the left and right renal arteries and the splenic artery. As a consequence, relief of limb ischemia was achieved and dialysis could be discontinued.

Acute Kidney Injury↗
PubMed2005

Membrane-penetrating trehalase from silkworm Bombyx mori. Molecular cloning and localization in larval midgut.

The main blood sugar in insects, trehalose, differs from glucose in mammals. To incorporate trehalose into cells and utilize it, tissue cells possess the enzyme trehalase (EC3.2.1.28), which catalyses trehalose into glucose, in the organellar membrane or in the cytoplasm. Soluble and membrane-bound trehalase proteins have been isolated from insects. To date, however, only genes encoding the soluble trehalase have been reported in insects. Soluble trehalase is therefore believed to become localized on the cell surface via modification. In contrast, cDNAs encoding trehalase localized on the apical cell surface via the glycosylphosphatidylinositol-anchor have been isolated from mammalian small intestines. The amino acid sequence contains a specific hydrophobic region and an upstream omega site, which is cleaved for glycosylphosphatidylinositol-attachment, at the C-terminus. Here, we describe a cDNA from the silkworm Bombyx mori that encodes a novel trehalase (type-2) with one transmembrane domain and lacking the omega site. Immunoblotting and immunohistochemical analyses demonstrated that in the midgut tissue of Bombyx larvae, soluble trehalase-1 is present mainly in goblet cell cavities, but membrane-bound trehalase-2 is predominantly seen on the visceral muscle surrounding the midgut. To our knowledge, this is the first report of a cDNA encoding trehalase that penetrates the cell membrane in insects and its cellular localization.

Amino Acid Sequence↗
PubMed2005

[Aortic dissection induced by symmetry aortic connector system].

A 74-year-old male with severe triple vessel disease underwent off-pump coronary artery bypass grafting (OPCAB). Preoperative computed tomography (CT) showed severely calcified ascending aorta. We revasculize the left coronary arteries with in situ internal thoracic artery (ITA) graft and the right coronary artery with a saphenous vein graft, which was attached to the disease-free portion of the aortic root, using Symmetry aortic connector system (ACS). Although the operation was uncomplicated, and postoperative course was uneventful until the 5th postoperative day when acute type A aortic dissection occurred. The patient died of aortic rupture on the 7th postoperative day. Necropsy disclosed that the entry located just on the proximal anastomotic site of the vein graft. It is possible placement of ACS device would trigger the dissecting process. With regard to the use of these one-shot devices for diseased aorta, its safety needs further investigation, even though it might be placed on an apparently intact portion.

Aged↗
PubMed2002

Transforming growth factor beta1 gene polymorphism in rheumatoid arthritis.

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease and synovial cells, antigen presenting cells, lymphocytes, and their cytokines might be associated with the disease. Transforming growth factor beta1 (TGFbeta1) has been reported to have important roles in unresolved inflammation, immune suppression, fibrosing processes, and angiogenesis. TGFbeta1 is highly expressed in joints in RA and is considered to be a regulator of anti-inflammation in RA. Polymorphisms of TGFbeta1 have been reported to be associated with the production of TGFbeta1 protein, and to increase the risk of acquiring several diseases. It was speculated that these polymorphisms might also be involved in RA, and therefore the TGFbeta1 codon 10 T869C polymorphism in a series of patients and controls was investigated. METHOD: A total of 155 patients with RA and 110 healthy subjects were studied. DNA was extracted from peripheral leucocytes and TGFbeta1 codon 10 T869C polymorphism was determined by polymerase chain reaction restriction fragment polymorphism. RESULTS: A significantly higher proportion of patients with RA with the T allele (CT type or TT type) was found compared with the CC type (p=0.039). CONCLUSION: The T allele, previously reported to be linked with production of TGFbeta1, may be associated with an increased risk of RA.

Adult↗
PubMed2002

Cloning, expression, and chromosomal localization of the mouse gene (Scgb3a1, alias Ugrp2) that encodes a member of the novel uteroglobin-related protein gene family.

The mouse UGRP gene family consists of two genes, Ugrp1 and Ugrp2. In this study, the genomic structure and expression patterns of Ugrp2 and its alternative spliced form were characterized. The authentic Ugrp2 gene has three exons and two introns, similar to the Ugrp1 gene, which produces a secreted protein. The Ugrp2 variant uses a sequence located between authentic exons 1 and 2, resulting in a cytoplasmic form due to a termination codon within the inserted sequence. Both mouse and human UGRP2 mRNAs are expressed in lung. In the case of human, the mRNA is expressed at the highest level in trachea, followed by salivary gland at a level similar to lung. Weak expression was also found in fetal lung and mammary gland. Ugrp2 was mapped by fluorescence in situ hybridization to mouse chromosome 11A5-B1 and human chromosome 5q35. These regions are known to be homologous. Interspecific mouse backcross mapping was also performed to obtain further detailed localization of mouse Ugrp1 and Ugrp2.

Alternative Splicing↗
PubMed2002

Transforming growth factor-beta gene polymorphism in sarcoidosis and tuberculosis patients.

SETTING: Transforming growth factor-beta (TGF-beta) plays an important role in many diseases, influencing as it does such processes as immune responses, fibrosing processes, and angiogenesis. Recently, polymorphisms have been described for TGF-beta that are associated with the risk of several diseases. In this study, we investigated whether TGF-beta 1 polymorphism has an effect on sarcoidosis and tuberculosis. OBJECTIVE: TGF-beta 1 Codon 10 T869C polymorphism was investigated in 110 healthy control subjects, 104 sarcoidosis patients, and 101 tuberculosis patients. DESIGN: The TGF-beta genotype was determined using polymerase chain reaction restriction fragment length polymorphism. RESULTS: We found no significant differences in TGF-beta genotypes between sarcoidosis patients and healthy controls or tuberculosis patients and controls. The long axis of the tuberculin skin test was larger in the CC type compared with the CT type. However, there was no association between the TGF-beta genotype and the roentgenographic stage, the disappearance of shadows, or organ involvement in sarcoidosis, nor any association between genotype, the extent or type of roentgenographic shadow, or detected volume of tubercle bacilli in tuberculosis. CONCLUSION: From the results, we believe that TGF-beta polymorphisms on the whole do not have a strong influence on disease onset or clinical progression in sarcoidosis and tuberculosis, although this polymorphism might have an effect on the immune response in a tuberculosis host.

Adult↗
PubMed2002

[Surgical treatment of traumatic rupture of the bicuspid aortic valve; report of a case].

A 27-year-old man was injured during a motocross game. He was suffered from dyspnea, orthopnea, and hemoptysis. The to-and-fro murmur was noticed 3 days after the accident and then the patient was admitted to our hospital. Echocardiography revealed severe aortic regurgitation. Computerized tomography also showed severe pulmonary contusions. Seventeen days after the accident the aortic valve replacement was performed. The aortic valve was anterior-posterior type bicuspid valve (fusion of right coronary cusp and light coronary cusp) and the tear was detected in the anterior cusp. The postoperative course was uneventful. Rupture of the aortic valve due to a blunt chest trauma is rare and reported in 20 cases previously in Japan. This case is the second report of traumatic rupture of the bicuspid aortic valve.

Adult↗
PubMed2001

Design and synthesis of non-peptidic inhibitors for the Syk C-terminal SH2 domain based on structure-based in-silico screening.

Structure-based in-silico screening was carried out for the Syk C-terminal SH2 domain. Fragments that could interact with the pY or pY+1 pockets were selected by our in-silico screening. After tethering two fragments bound to these pockets, we have designed and synthesized new compounds that show favorable interaction with the pY+3 pocket. One such compound, having a cyclohexylmalonic acid moiety identified as a novel potent phosphotyrosyl mimetic, exhibited an affinity comparable to that of the monophosphorylated ligand peptide.

Binding, Competitive↗
PubMed2001

Alternate venous drainage and return of warmed blood combined with continuous hypothermic visceral perfusion. A new adjunct of thoracoabdominal aortic aneurysm repair.

OBJECTIVE: As a new adjunct to surgical repair for a thoracoabdominal aortic aneurysm, we have devised and used visceral perfusion in combination with alternate venous drainage and return of warmed blood in 4 patients. METHODS: Surgical repair of a thoracoabdominal aortic aneurysm of Crawford type III (n = 1) or type IV (n = 3) was performed. During visceral branch reconstruction, hypothermic blood (30-32 degrees C) was perfused continuously to each visceral and renal artery at a total flow rate of 300 ml/min, in combination with alternate venous drainage and return of warmed blood to the inferior vena cava. RESULTS: The visceral and renal perfusion time was 115 +/- 55 (with a range from 52 to 190) minutes. All 4 patients recovered uneventfully. CONCLUSIONS: Alternate venous drainage and return of warmed blood combined with continuous hypothermic visceral perfusion were a useful adjunct to thoracoabdominal aneurysm repair during reconstruction of visceral and renal arteries.

Aged↗
PubMed2001

Aortic valve replacement in a heavily calcified "porcelain" aorta.

Although a heavily-calcified so-called "porcelain" aorta is encountered infrequently, its association presents a formidable problem in cardiac surgery. Here we describe a case of severe aortic stenosis and coronary artery disease combined with the circumferentially calcified aorta. The patient was a 63-year-old man who successfully underwent double coronary artery bypass grafting and aortic valve replacement during hypothermic perfusion through the right axillary artery with endoaortic balloon occlusion, followed by minimal endarterectomy of the calcified plate along the aortotomy, and closure of the aorta buttressed with bovine pericardium under circulatory arrest.

Aortic Diseases↗
PubMed2001

Samui, a novel cold-inducible gene, encoding a protein with a BAG domain similar to silencer of death domains (SODD/BAG-4), isolated from Bombyx diapause eggs.

Cellular responses to cold-acclimation have not yet been studied in depth. To explore this field, we focussed on insect diapause development. Although embryonic diapause of Bombyx mori is sustained at 25 degrees C, chilling at 5 degrees C for 2 months causes diapause termination, a transition that is marked when the sorbitol dehydrogenase gene (SDH) is activated. To clarify the relationship between this activation and incubation at 5 degrees C, we isolated a novel cold-inducible gene, Samui. Expression of Samui mRNA and protein was activated after incubation at 5 degrees C for 5-6 days, lasted for another 30 days and then weakened. Exposure to 25 degrees C suppressed both mRNA and protein expression. In nondiapause eggs incubated at 5 degrees C, Samui was also up-regulated, although the expression was weaker. Samui contained nuclear localization-signals, a ssDNA-binding motif and a BAG domain similar to that of SODD/BAG-4. Because Samui could bind to HSP70, it is a member of BAG protein family. It is proposed that Samui serves to transmit the '5 degrees C signal' for SDH expression in diapause eggs, while also protecting against cold-injures in nondiapause eggs, through binding to respective partners. This is the first report that a member of BAG protein family is up-regulated by cold.

Amino Acid Sequence↗
PubMed2001

Survey of congenital anomalies associated with cleft lip and/or palate in 701,181 Japanese people.

There have been many reports on congenital anomalies associated with cleft lip and/or palate (CL/CLP) in Japan. However, these reports included data only on patients who came to hospitals; thus the real situation regarding these anomalies remains unclear. Therefore, we surveyed newborns at all delivery facilities in the central area of Japan for the presence of these anomalies, following their progress for 12 consecutive years; at the end of that time, questionnaires were collected and analyzed. In this article, we describe our results.

Birth Weight↗
PubMed2001

claudin-18, a novel downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor, encodes lung- and stomach-specific isoforms through alternative splicing.

T/EBP/NKX2.1, a member of the NKX family of homeodomain-containing transcription factors, regulates the expression of a number of genes in lung and thyroid. Here we describe the isolation and characterization of a novel target gene, termed claudin-18, that is down-regulated in the lungs of T/ebp/Nkx2.1-null mouse embryos. The gene product exhibits an amino acid sequence similar to those of the claudin multigene family of proteins that constitute tight junction strands in epithelial cells. The gene was localized by fluorescence in situ hybridization to mouse chromosome 9 at region 9E3-F1 and to human chromosome 3 at region 3q21-23. The claudin-18 gene has two promoters, each with its own unique exon 1 that is spliced to common exons 2 through 5. Alternative usage of these promoters leads to production of lung and stomach-specific transcripts. The downstream lung-specific promoter contains two T/EBP/NKX2.1 binding sites responsible for trans activation of the gene by T/EBP/NKX2.1 in lung cells. Only claudin-18 was down-regulated in T/ebp/Nkx2.1-null embryo lungs among 11 claudin transcripts examined. Furthermore, the claudin-18 transcript has an alternative 12-bp insertion derived from the 5' end of intron 4, which produces a C-terminally truncated isoform in lung and stomach. Immunohistochemistry demonstrated complete membrane localization of claudin-18 with small focal dots in the lung and stomach epithelial cells. Immunogold electron microscopy analysis revealed that claudin-18 is concentrated at the cell-cell borders of epithelial cells. These unique features suggest a potentially important role for claudin-18 in the structure and function of tight junctions in lung and stomach.

Alternative Splicing↗
PubMed2001

UGRP1, a uteroglobin/Clara cell secretory protein-related protein, is a novel lung-enriched downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor.

A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-PCR analysis. Cotransfection assays using a T/EBP/NKX2.1 expression construct with Ugrp1 promoter-luciferase reporter constructs confirmed that T/EBP/NKX2.1 regulates Ugrp1 gene activity at the transcriptional level. Thus, Ugrp1 is a downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor. Changes in UGRP1 mRNA levels in lungs from antigen-sensitized mice suggest the possible involvement of UGRP1 in inflammation.

Alternative Splicing↗
PubMed2001

Elevated level of soluble HLA class I antigens in serum and bronchoalveolar lavage fluid in patients with sarcoidosis.

OBJECTIVE: Soluble HLA class I antigens (sHLAs) in human serum have been reported to be associated with allografts and autoimmune disease and could modify immunological reactions induced by membrane type HLAs. To investigate the clinical significance of sHLAs in sarcoidosis, we assessed concentrations of sHLAs in both serum and bronchoalveolar lavage fluid (BALF) and also examined their production by peripheral blood mononuclear cells (PBMCs) and BALF cells. METHODS: Concentrations of sHLAs were determined by enzyme-linked immunosorbent assay, using a monoclonal antibody against HLA class I (W6/32) and an enzyme-labeled polyclonal antibody to human beta2-microglobulin. PBMCs and BALF cells were cultured in the presence or absence of either LPS or PHA. PATIENTS: Serum levels of sHLAs were assessed in 96 patients with sarcoidosis and in 32 healthy control subjects. sHLAs concentrations in BALF were also investigated in 17 active sarcoidosis patients and in 13 control subjects. RESULTS: sHLAs levels in both serum and BALF were higher in sarcoidosis cases than in control subjects (p<0.05, in both). In the patients, values were significantly higher in active than in inactive stages (p<0.001) and significantly correlated with angiotensin-converting enzyme (ACE) levels. Both PBMCs and BALF cells produced enhanced amounts of sHLAs in patients with active sarcoidosis compared with those in control subjects. CONCLUSION: These results demonstrated that the level of sHLAs in serum is a useful index of disease activity of sarcoidosis, partly reflecting production by PBMCs and BALF cells.

Adult↗
PubMed2000

Single-molecular AFM probing of specific DNA sequencing using RecA-promoted homologous pairing and strand exchange.

The specific sequence in a linearlized double-stranded DNA target has been identified at a single-molecular level by atomic force microscopy (AFM). This was accomplished using RecA-coated, single-stranded DNA probes which were paired with a specific complementary DNA sequence in a linear double-stranded DNA target by strand-exchange reaction at a homologous sequence site with target DNA. The sites of interaction between the nucleoprotein filaments and the double-stranded DNA targets were directly visualized by AFM in solution containing 4 mM magnesium acetate. Measurements of the position of RecA-coated probes paired to individual target DNA showed that DNA probes specifically paired at their corresponding homologous target sequences. Strand exchange promoted by RecA and the visualization by AFM provided a rapid and efficient way to identify homologous sequence on a single-molecule target DNA.

Base Sequence↗