Biomedical subjects

K Naito

Publications and source records attributed to K Naito.

At least 19 recordsLinked to original sources

PubMed2006

Detection of new anti-neutral glycosphingolipids antibodies and their effects on Trk neurotrophin receptors.

We screened sera from patients with various neurological disorders for the presence of anti-neutral glycosphingolipids antibodies and only found them in sera from relapsing polychondritis with limbic encephalitis patients. Neutral glycosphingolipids are resident in membrane lipid rafts where high affinity nerve growth factor (NGF) receptor, Trk is co-localized. Therefore, we examined whether these antibodies influence the action of NGF in NGF-responsive cells. The results strongly suggest that these antibodies enhance NGF-induced Trk autophosphorylation and neurite outgrowth as well as neurofilament M expression. These data strongly indicate that these anti-neutral glycosphingolipids antibodies have a functional impact on NGF-Trk-mediated intracellular signal transduction pathway.

Animals↗

PubMed2006

Single nucleotide polymorphisms in DNA repair genes might be prognostic factors in muscle-invasive bladder cancer patients treated with chemoradiotherapy.

DNA repair enzymes repair DNA damaged by platinum agents and ionising radiation. Single nucleotide polymorphisms (SNPs) in DNA repair genes modulate the repair capacity and might affect response and prognosis following platinum-based chemoradiotherapy (CRT). We investigated associations between the functional SNPs in DNA repair genes and response and survival in muscle-invasive bladder cancer patients treated with CRT to determine the predictive value of the SNPs in patient selection for bladder conservation therapy. The study group comprised 78 patients who underwent CRT for transitional cell carcinoma of the bladder. Single nucleotide polymorphisms in xeroderma pigmentosum complementation groups C (Lys939Gln, A/C), D (XPD; Lys751Gln, A/C), and G (Asp1104His, G/C), and X-ray repair cross-complementing groups 1 (XRCC1; Arg399Gln, G/A) and 3 (Thr241Met, T/C) genes were genotyped. Combined genotypes with at least one variant allele in XPD or XRCC1 were significantly associated with improved cancer-specific survival compared with remaining groups (P=0.009). In multivariate analysis, only the combined XPD and XRCC1 genotypes were independently associated with cancer-specific survival (P=0.04). The association was stronger in stage T3/T4 patients (P=0.0008). These results suggest that combined XPD and XRCC1 genotypes might be prognostic factors in muscle-invasive bladder cancer patients treated with CRT.

Aged↗

PubMed2006

Anatomicopathological study of vascular and biliary systems using cast samples of Fasciola-infected bovine livers.

In 117 livers with fascioliasis, this study was focused on the number of Fasciola, the number and intrahepatic localization of affected hepatic ducts and bile ducts, and the degree of fibrosis in the hepatic segments and bile ducts. The degree of pathological changes in bile ducts caused by fascioliasis was classified into five levels. The site of Fasciola habitation was most often the hepatic ducts of the porta hepatis: it was the left hepatic duct in 101 livers and the right hepatic duct in 88 livers. Casts were prepared by infusing synthetic resin into the hepatic arterial, portal, hepatic venous and biliary systems of 15 bovine livers with fascioliasis and then examined. In the left lobe, quadrate lobe, and caudate process where atrophic fibrosis was noted, the bile ducts became rod-shaped by losing branches, and the samples resembled dead branches of liver. Portal branches were thinned or completely terminated with marked fibrosis. Fine and irregular newly formed bile ducts not parallel with portal branches were observed in livers with markedly chronic fascioliasis. Distal portal branches in the right lobe, caudate lobe, and papillary process showed hypertrophic proliferative changes. The arterial system was generally well developed in thickened walls of bile ducts and formed vascular beds, and surrounded the bile ducts as tubes. In livers with severe fibrosis, capillaries were markedly developed and resembled glass cotton.

Animals↗

PubMed2006

Distribution, structure, organ-specific expression, and phylogenic analysis of the pathogenesis-related protein-3 chitinase gene family in rice (Oryza sativa L.).

Rice (Oryza sativa L.) pathogenesis-related (PR)-3 chitinases, like other PR proteins, are each coded by one of the genes of a multigene family in the plant genome. We assembled the database information about rice PR-3 chitinase sequences. A total of 12 PR-3 chitinase loci (Cht1 to Cht12) were found deployed in the rice genome. Some of the loci were occupied by 2 or more alleles. For all the loci expect Cht4, Cht5, Cht6, and Cht11, the amino acid sequence was polymorphic between japonica and indica varieties of rice, but glutamic acid acting as a catalytic residue was completely conserved in all the loci expect Cht7. All the genes except Cht7, which was not tested in this study, were transcripted in some organs (leaf, sheath, root, and meristem) of rice plants. These results suggest that chitinase proteins encoded by the genes at these loci have important biological effects, at least antifungal activities, on rice plants. We also proposed a new classification of rice PR-3 chitinases based on their domain structures. This classification was consistent with the results of phylogenetic analysis of rice chitinases.

Alleles↗

PubMed2005

Increased expression of Leydig cell haem oxygenase-1 preserves spermatogenesis in varicocele.

BACKGROUND: Oxidative stress is involved in the pathogenesis of testicular disorders. Haem oxygenase-1 (HO-1) plays an important cytoprotective role against oxidative stress. We investigated the presence of oxidative stress, represented by generation of 4-hydroxy-2-nonenal (4-HNE)-modified proteins, and expression of HO-1 in varicocele testes of human. METHODS: Thirty testicular biopsies from patients with left varicocele and 10 from patients with normal spermatogenesis were included. Generation of 4-HNE-modified proteins was examined as a marker of oxidative stress. Expression of HO-1 was assessed by western blotting and immunohistochemistry. The expression was compared with clinico-pathological parameters. RESULTS: Increased generation of 4-HNE-modified proteins was observed in varicocele testes. HO-1 expression was significantly correlated with varicocele grade (P < 0.01 in grade 2 and 3 compared to control) and expression of 4-HNE-modified proteins (r = 0.508, P < 0.01). The immunoreactivity was increased in Leydig cells in varicocele testes. There were significant correlations between age, total motile sperm count, Johnsen's mean score and HO-1:4-HNE-modified protein ratio (r = 0.206, 0.405 and 0.408, P = 0.027, 0.027 and 0.025 respectively). CONCLUSIONS: In testes with varicocele, there are increases in 4-HNE-modified proteins, suggesting that oxidative stress is present. Increased HO-1 expression, mainly in Leydig cells, is considered to protect the cells against oxidative stresses in varicocele testes.

Adult↗

PubMed2005

Efficacy of gemtuzumab ozogamicin on ATRA- and arsenic-resistant acute promyelocytic leukemia (APL) cells.

Acute promyelocytic leukemia (APL) cells express a considerable level of CD33, which is a target of gemtuzumab ozogamicin (GO), and a significantly lower level of P-glycoprotein (P-gp). In this study, we examined whether GO was effective on all-trans retinoic acid (ATRA)- or arsenic trioxide (ATO)-resistant APL cells. Cells used were an APL cell line in which P-gp was undetectable (NB4), ATRA-resistant NB4 (NB4/RA), NB4 and NB4/RA that had been transfected with MDR-1 cDNA (NB4/MDR and NB4/RA/MDR, respectively), ATO-resistant NB4 (NB4/As) and blast cells from eight patients with clinically ATRA-resistant APL including two patients with ATRA- and ATO-resistant APL. The efficacy of GO was analyzed by (3)H-thymidine incorporation, the dye exclusion test and cell cycle distribution. GO suppressed the growth of NB4, NB4/RA and NB4/As cells in a dose-dependent manner. GO increased the percentage of hypodiploid cells significantly in NB4, NB4/RA and NB4/As cells, and by a limited degree in NB4/MDR and NB4/RA/MDR cells. Similar results were obtained using blast cells from the patients with APL. GO is effective against ATRA- or ATO-resistant APL cells that do not express P-gp, and the mechanism of resistance to GO is not related to the mechanism of resistance to ATRA or ATO in APL cells. Leukemia (2005) 19, 1306-1311. doi:10.1038/sj.leu.2403807; published online 26 May 2005.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2005

Three-dimensional vasculature of the bovine liver.

To clarify anatomical distribution of Fasciola infection, the vascular and ductal architectures of the liver were studied by means of corrosion cast technique using synthetic resin. The arteria hepatica propria (AP) passes as the arteria gastroduodenalis (AG); AP becomes the left trunk after the porta hepatis; AP passes on the right side of vena porta communis (VPC) and projects AG while curving in a U-shape below the portal vein. Hepatic veins located between the vena hepatica media (HM) and vena hepatica dextra (HD) varied widely among specimens and were irregular, including the vena hepatica dorso-lateralis sinistra (Hds), vena hepatica dorso-lateralis dextra (Hdd), vena hepatica lobi caudati (Hlc), venae hepaticae processus caudati (Hpc), venae hepaticae processus papillaris (Hpp), and the hepatic vein to the dorsal intermediate part, which directly or indirectly drained into the vena cava caudalis. The courses of the bovine hepatic veins were markedly diverse, and anastomoses between vena hepatica sinistra (HS) and Hds were observed in about a half of the livers. The portal vein entered the liver as VPC slightly above the centre of the right lobe on the visceral surface. The intermediate or transverse part [pars transversa trunci sinistri (PTS)] of truncus sinister (TS), which extends from the entry of the portal vein into the left lobe of the liver, was slightly arched downward [pars umbilicalis trunci sinistri (PUS)]. The portal vein further arched from the distal end of TS to the umbilical vein and ran towards the inter-lobar incision between the left lobe and quadrate lobe. Based on these branches, hepatic segments were determined as 13 or 14 areas. A total of 15 bile ducts were derived from various lobes. The hepatic duct was about 2.6-6 cm long from the confluence of the right and left hepatic ducts to the division of the cystic duct and the common hepatic duct.

Animals↗

PubMed2005

Metastatic retinoblastoma of the maxilla and mandible.

Metastatic retinoblastoma of the jaws is very rare. We present a 4-year-old boy with metastatic retinoblastoma that involved both the maxilla and mandible simultaneously. Enhanced CT indicated bone-destructive masses with partially non-enhanced area and enhanced margin in the right maxilla and left mandible. MRI showed well-delineated masses that were isointense on T(1) weighted images and hyperintense on T(2) weighted images. Four weeks after chemotherapy and bone marrow transplantation, the size of lesions remarkably decreased. The patient died 19 months later with extensive tumour metastases despite additional chemotherapy. In this case, the dental crypt of a permanent tooth was considered the potential target through which retinoblastoma metastasized to the jaws.

Child, Preschool↗

PubMed2004

Allelic imbalance at 1p36 may predict prognosis of chemoradiation therapy for bladder preservation in patients with invasive bladder cancer.

Invasive bladder cancers have been treated by irradiation combined with cis-platinum (CDDP) as a bladder preservative option. The aim of this study was to find a marker for predicting patient outcome as well as clinical response after chemoradiation therapy (CRT) by investigating allelic loss of apoptosis-related genes. A total of 67 transitional cell carcinomas of the bladder treated by CRT (median dose: 32.4 Gy of radiation and 232 mg of CDDP) were studied. We investigated allelic imbalances at 14 loci on chromosomes 17p13 and 1p36 including the p53 and p73 gene regions by fluorescent multiplex PCR based on DNA from paraffin-embedded tumour specimens and peripheral blood. The response to CRT was clinical response (CR) in 21 patients (31%), partial response (PR) in 31 (46%), and no change(NC) in 15 (22%). There was no statistical correlation between treatment response and clinical parameters, such as tumour grade, stage, radiation dose, or CDDP dose. The frequencies of allelic imbalance for TP53 and TP73 were 21 and 56%, respectively; neither was correlated with clinical treatment response and tumour stage or grade. There was no statistical correlation between treatment response and allelic imbalance at the other 12 loci. We found a significant correlation between cancer-specific survival and an imbalance of D1S243 (P=0.0482) or TP73 (P=0.0013) using a Log-rank test, although other loci including TP53 did not correlate with survival (P=0.4529 Multivariate analysis showed performance status (P=0.0047), recurrence (P=0.0017), and radiation doses (P=0.0468) were independent predictive factors for cancer-specific survival. However, an allelic imbalance of TP73 was the most remarkable independent predictive factor of poor patient survival (P=0.0002, risk ratio: 3382). Our results suggest that the allelic loss of the p73 gene predicts a clinical outcome of locally advanced bladder cancer when treated by CRT.

Aged↗

PubMed2004

Effects of FTY720 on rat lymphoid organs.

INTRODUCTION: In this study, we examined the in vivo effect of FTY720 on rat thymus and spleen. MATERIALS AND METHODS: Inbred male Lewis (RT-I(l)) rats, 5-weeks-old, received FTY720 (0.1, 1, or 10 mg/kg) by intramuscular injection into 1 of 4 limbs daily for 7 days. The rats were humanely killed at 1, 3, 5, or 7 days after starting administration of FTY720. The thymus and spleen were obtained for hematoxylin and eosin (HE) as well as immunoperoxidase staining using the antibodies OX8 (CD8), W3/25 (CD4), and OX6 (major histocompatibility complex class II). RESULTS: HE staining revealed marked atrophy in the cortical region of the thymus among rats administered FTY720 at the dose of 10 mg/kg. The atrophy extended to the whole cortex. On day 7 of administration of FTY 720 (10 mg/kg), the medulla of the thymus showed relative expansion due to cells accumulation. Also, the spleens of FTY720-treated rats revealed an obvious reduction in the T-cell-dependent areas around the central artery. In conclusion, the immunosuppressive effect of FTY720 may be due to an inhibitory effect on T-cell emigration from the thymus to the periphery.

Animals↗

PubMed2004

Two cases of recurrent IgA nephropathy following kidney transplantation.

Recurrence of immunoglobulin (Ig) A nephropathy following kidney transplantation has been described as occurring in 40% to 60% of cases. Although this type of recurrence was considered a benign condition for a long time, more recent data showed that recurrent transplant IgA nephropathy may be a significant contributor to graft loss. We present 2 cases of recurrent IgA nephropathy following kidney transplantation. In case 1, renal function remained stable with a creatinine level of 1.2 mg/dL at 5 months after diagnosis and 61 months after transplantation. In case 2, the patient lost his graft and returned to regular hemodialysis at 36 months after diagnosis and 125 months after kidney transplantation.

Adult↗

PubMed2004

Differential diagnosis of neonatal mild hypergalactosaemia detected by mass screening: clinical significance of portal vein imaging.

The aetiology of hypergalactosaemia in 100 neonates detected by screening using the Paigen method is discussed. Hypergalactosaemia was transient in 94 cases and persistent in 6. The aetiology among transient cases was unknown in 55, delayed closure of the ductus venosus in 19, heterozygous UDP-galactose 4-epimerase (GALE) deficiency in 16, and heterozygous galactose-1-phosphate uridyltransferase (GALT) deficiency in 6. The aetiology among persistent cases was hepatic haemangioendothelioma with portovenous shunting in 2, and patent ductus venosus with hypoplasia of the intrahepatic portal vein, citrin deficiency, homozygous GALE deficiency, and heterozygous GALE deficiency in one patient each. The abnormalities of the portal system were identified ultrasonographically at the initial consultation and measurements of the total bile acid and alpha-fetoprotein concentrations were helpful in resolving the differential diagnosis. The causes of hypergalactosaemia varied, but a major cause was portosystemic shunt. Evaluation of patients with hypergalactosaemia should not be limited to enzymatic analysis, but should also include hepatic imaging, especially ultrasonography. Additionally, determination of total bile acids and alpha-fetoprotein is helpful in identifying the aetiology of hypergalactosaemia in infants.

Acute Disease↗

PubMed2004

A nationwide survey of deep fungal infections and fungal prophylaxis after hematopoietic stem cell transplantation in Japan.

We conducted a nationwide survey to define incidence of deep fungal infections and fungal prophylaxis practices after HSCT. In all, 63 institutions responded. Total number of in-patient transplantations was 935: 367 autologous, 414 allogeneic myeloablative, and 154 allogeneic reduced-intensity (RIST) (n=154). Number of patients who were cared for in a clean room at transplant was 261 (71%) in autologous, 409 (99%) in conventional and 93 (66%) in RIST, respectively. All patients received prophylactic antifungal agents; 89% fluconazole. Number of patients who received the dosage recommended in the CDC guidelines (400 mg/day) was 135 (42%) in conventional transplant and 34 (30%) in RIST (P=0.037). Number of patients who received fluconazole until engraftment and beyond day 75 in conventional transplant vs RIST was, respectively, 324 (100%) vs 109 (97%), and 39 (12%) vs 18 (16%), with no significant difference between the two groups. A total of 37 patients (4.0%) were diagnosed with deep fungal infections; autologous transplantation (0.03%), conventional transplantation (6.0%) and RIST (7.1%). Wide variations in antifungal prophylaxis practice according to the type of transplant and the institutions, and deep fungal infection remain significant problems in RIST.

Antifungal Agents↗

PubMed2004