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Kazuhiro Kondo

Publications and source records attributed to Kazuhiro Kondo.

At least 19 recordsLinked to original sources
PubMed2006

Staged operations for posthemorrhagic hydrocephalus in extremely low-birth-weight infants with preceding stoma creation after bowel perforation: surgical strategy.

CASE REPORT: We report a complicated extremely low-birth-weight (ELBW) infant with posthemorrhagic hydrocephalus after intraventricular hemorrhage and preceding stoma creation after bowel perforation who was treated with staged operations, including shunting and external ventricular drainage. The first operation was a temporary valveless ventriculoperitoneal (VP) shunt placement until the time of the stoma closure. The stoma was successfully closed 3 months after the first operation when the peritoneal tube was drawn out from the chest wall and the VP shunt system was temporarily used as an external drainage with a long subcutaneous tunnel. One month after the second operation, final VP shunt placement was performed after good healing of bowel anastomosis was surely confirmed. The previous peritoneal shunt tube was cut behind the ear, removed, and replaced with a valve-regulated VP shunt system. CONCLUSION: This staged strategy is a safe and feasible option for complicated ELBW infants with preceding stoma and hydrocephalus.

Female↗
PubMed2006

Segmentectomy for reactive lymphoid hyperplasia of the liver: Report of a case.

We report a case of reactive lymphoid hyperplasia (RLH) of the liver in a 72-year-old woman without any symptoms. To our knowledge, only 11 other cases of this disease have ever been reported. The lesion was found incidentally during a medical examination, as a hypoechoic mass in segment 3 of the liver on ultrasonography. The findings of computed tomography, magnetic resonance imaging, and angiography suggested a malignancy. Frozen section diagnosis of an intraoperative needle biopsy suggested malignant lymphoma, so we performed lateral segmentectomy of the liver. Macroscopically, the tumor was well defined, white, and firm. Microscopically, there was polymorphous lymphoplasmacytic infiltration, with various-sized and -shaped lymphoid follicles. Lymphocytic infiltration was also observed in the portal tracts around the nodular lesion. Immunohistochemical study revealed polyclonality, confirming a pathological diagnosis of RLH of the liver. We discuss the clinicopathologic characteristics of this unusual disease.

Aged↗
PubMed2006

Function of an N-heterocyclic carbene ligand based on concept of chiral mimetic.

Function of a new N-heterocyclic carbene ligand based on the concept of a chiral mimetic is described. With (4R,5R)-4,5-diphenyl-1,3-dialkyl-4,5-dihydro-3H-imidazol-1-ium tetrafluoroborates as N-heterocyclic carbene precursors, Rh-catalyzed enantioselective arylation (up to 27% ee) of aromatic aldehydes with arylboronic acids and Pd-catalyzed enantioselective intramolecular alpha-arylation (up to 66% ee) of N-(2-bromoaryl)-N-alkyl-2-arylpropanamides are investigated.

Heterocyclic Compounds↗
PubMed2005

Gene expression analysis using a modified HiCEP method applicable to prokaryotes: a study of the response of Rhodococcus to isoniazid and ethambutol.

We established a novel method to analyze the gene expression of prokaryotes by modifying and optimizing the HiCEP (high coverage gene expression analysis) method, which was originally developed for eukaryotic gene expression profiling. Following the removal of abundant rRNA, the mRNA of prokaryotic cells was enzymatically polyadenylated and subjected to HiCEP analysis. This method was highly reproducible due to selective PCR that was performed by using adaptor specific primers. We confirmed induction of tipA and induction or suppression of cspA, which are genes that are obtained from distinctive actinomycetes and responded to thiostrepton and temperature stress, respectively. Further, we applied this method to explore the gene expression profile of Rhodococcus erythropolis in response to drugs that inhibit cell wall synthetic pathways, and we were able to identify 35 upregulated genes. Among these genes, we confirmed the upregulation of 22 genes by using RT-PCR (reverse transcriptase-polymerase chain reaction). Some of these genes are involved in the synthesis of mycolic acid and arabinogalactan, suggesting a cell response to drug treatment by regulation of the genes involved in cell wall synthesis. This method could prove to be a useful technique for gene expression analysis of prokaryotes, particularly nonmodel strains with unknown genome sequences.

Antitubercular Agents↗
PubMed2005

Gene expression profiles of peripheral and cord blood mononuclear cells altered by thymic stromal lymphopoietin.

Thymic stromal lymphopoietin (TSLP) was reported to induce dendritic cells to produce Th2-attracting chemokines, followed by allergic inflammation through stimulating not only CD4-positive T cells but also CD8-positive T cells. Therefore, in this experiment, GeneChip and hierarchical clustering were applied to screen the molecules in whole immunity triggered by TSLP directly and indirectly using both adult peripheral and cord blood mononuclear cells as well as isolated monocytes. Gene expression profiles screened a variety of molecules that are triggered by TSLP with or without CD40 ligation. In the profile, RNA expressions of indoleamine 2,3-dioxygenase, that is known to induce anergy of T cells and natural killer cells in protecting fetal rejection; many kinds of proteasomes that were reported to trigger cytokine production by inhibiting suppressors of NF-kappaB; and several kinds of chemokines increased, whereas RNA expression of superoxide dismutase 1 decreased, which was unexpected but considered worthy of notice. Expression of chemokines at protein levels and enzymatic activity of indoleamine 2,3-dioxygenase was further confirmed to increase in the presence of TSLP using ELISA and HPLC, respectively. These results suggest that the advent of microarray technology may enable us to screen novel molecular targets to treat TSLP-related allergic inflammation.

Adult↗
PubMed2005

Risk factors for early death after liver resection in patients with solitary hepatocellular carcinoma.

BACKGROUND/PURPOSE: Although most patients who receive hepatectomy for a solitary hepatocellular carcinoma (HCC) have a relatively fair result, some have a poor prognosis. The aim of this study was to evaluate the risk factors for early death after hepatectomy in patients with a solitary HCC. METHODS: Eligible patients (n=110) who had undergone hepatectomy for solitary HCC between 1990 and 2002 and were able to be followed up for more than 2 years after the hepatectomy were divided into two groups, those who died of cancer recurrence within 2 years (early-death group; n=18) and those who survived for more than 2 years after the surgery (survival group; n=92). Risk factors for early death after liver resection were evaluated by univariate and multivariate analyses. RESULTS: The gross tumor classification, tumor diameter, macroscopic portal vein invasion, microscopic growth pattern, microscopic vascular invasion (MVI), and the width of the surgical margin were significant (P<0.05) factors by univariate analysis. Multivariate analysis showed that the presence of MVI was an independent and significant risk factor for early death of recurrence. CONCLUSIONS: Among patients with solitary HCC, the presence of MVI indicates a poor prognosis. These patients need adjuvant chemotherapy in the early period after hepatectomy.

Aged↗
PubMed2005

Prognostic benefit of selective portal vein occlusion during hepatic resection for hepatocellular carcinoma.

BACKGROUND: The aim of this study was to clarify whether the types of portal vein (PV) occlusion during hepatectomy affect the long-term outcome in patients with hepatocellular carcinoma (HCC). METHODS: Eighty-six patients who had undergone curative hepatic resection for HCC were divided on the basis of the type of PV occlusion into 2 groups: total PV occlusion (TPVO, n = 56) and selective PV occlusion (SPVO, n = 30) groups. The recurrence-free survival was compared between the groups, and factors affecting recurrence-free survival were examined by univariate analyses followed by multivariate analyses. Moreover, the patients with a single nodular HCC less than 5 cm in diameter were abstracted from both groups, and the recurrence-free survival rate was compared. RESULTS: The patients and tumor-related factors were similar in the TPVO and SPVO groups. The recurrence-free survival was better in the SPVO group than in the TPVO group (median recurrence-free survival time, 1520 vs 561 days, P = .017). The type of PV occlusion was a significant factor for recurrence-free survival by univariate analysis but did not reach significance ( P = .052) by multivariate analysis. In the selected patients who had a single nodular HCC less than 5 cm in diameter, the recurrence-free survival was also significantly better in the SPVO group than in the TPVO group (median recurrence-free survival time, 2613 vs 1003 days, P = .018). CONCLUSIONS: Hepatectomy under selective PV occlusion seems to improve the recurrence-free survival in patients with HCC.

Adult↗
PubMed2005

Human herpesvirus 6 open reading frame U14 protein and cellular p53 interact with each other and are contained in the virion.

A mass spectroscopic analysis of proteins from human herpesvirus 6 (HHV-6)-infected cells showed that the HHV-6 U14 protein coimmunoprecipitated with the tumor suppressor p53. The binding of U14 to p53 was verified by coimmunoprecipitation experiments in both Molt-3 cells infected with HHV-6 and 293 cells cotransfected with U14 and p53 expression vectors. Indirect immunofluorescence assays (IFAs) showed that by 18 h postinfection (hpi) U14 localized to the dot-like structures observed in both the nucleus and cytoplasm where p53 was partly accumulated. Despite Northern blotting evidence that U14 follows late kinetics, the U14 protein was detected immediately after infection (at 3 hpi) by IFA. In addition, by Western blotting, U14 was detected at 0 hpi or in the presence of cycloheximide which completely abolished the expression of IE1 protein. In addition to U14, p53 was detected at 0 hpi although it was not detected in mock-infected cells. Furthermore, both U14 and p53 were clearly detected in the viral particles by Western blotting and immunoelectron microscopy, supporting the idea that U14 and p53 are incorporated into virions. Our study provides the first evidence of the incorporation of cellular p53 into viral particles and suggests that p53 may play an important role in viral infection.

Blotting, Northern↗
PubMed2005

[Human herpesvirus latency and fatigue].

Human herpesvirus (HHV)-6 and HHV-7 establish life-long latency, a hallmark of herpesviruses, reactivate frequently, and are shed in saliva. To investigate the viral reactivation, we have identified the latency-associated transcripts of HHV-6, and have revealed the partial mechanism of HHV-6 reactivation. HHV-6 established latency in the macrophage, kept a fairly stable intermediate stage between latency and reactivation, and the viral reactivation was induced by two or more factors. To identify the factor (s) of HHV-6 reactivation, we studied the association between HHV-6 reactivation and the work-induced fatigue in healthy adults. Reactivation of HHV-6 was examined for viral DNA by semi-quantitative PCR method. As a result, 88% of healthy adults shed the reactivated HHV-6 in the saliva during the fatigue, and 23% shed HHV-6 after holidays (approximately 1 week). The copy number of HHV-6 DNA was also reduced after holidays. In HHV-7, 52% of healthy adults shed the reactivated HHV-7 in the saliva during the fatigue, and 30% shed HHV-7 after holidays; however, there were no significant differences in their positive ratio and in the amount of viral DNA. These findings suggest that HHV-6 is reactivated during the work-induced fatigue, and HHV-6 reactivation can be an objective biomarker for fatigue.

Adult↗
PubMed2004

Human herpesvirus 6 (HHV-6) is transmitted from parent to child in an integrated form and characterization of cases with chromosomally integrated HHV-6 DNA.

We obtained 7,566 peripheral blood mononuclear cell (PBMC) samples from 2,332 individuals and screened them for human herpesvirus infection. We identified five individuals who persistently harbored high copy numbers of human herpesvirus 6 (HHV-6) DNA in their PBMCs. HHV-6 DNA was also detected in other somatic tissues of these individuals. Five additional cases were identified among their family members. For two of these families, chromosomally integrated HHV-6 DNA (CIHHV-6) was detected in the PBMCs by fluorescence in situ hybridization. The prevalence of CIHHV-6 among all the subjects was 0.21%. The HHV-6 DNA was variant B in four families and variant A in one family. Antibodies to immediate early antigen and glycoprotein B were detected in 57 and 14% of individuals with CIHHV-6 and in 0 and 60% of healthy volunteers without CIHHV-6, respectively. HHV-6 could not be isolated from PBMCs with CIHHV-6. These cases shared no clinical features, and included three healthy individuals. Our data suggest that CIHHV-6 is rare but detectable in the general population and that hereditary transmission is one of the routes of HHV-6 transmission.

Antibodies, Viral↗
PubMed2004

Productive human herpesvirus 6 infection causes aberrant accumulation of p53 and prevents apoptosis.

p53 plays an important role in tumour suppression in cells exposed to some genotoxic stresses. We found that the p53 protein level was increased in a variety of cell lines infected with human herpesvirus 6 (HHV-6). Because the elevation in p53 began very soon after infection (4 h) and did not occur with UV-inactivated virus infection, it appeared to require the expression of one or more viral immediate-early (IE) genes. To elucidate the mechanism of p53 induction, we investigated its regulation at the protein level. Pulse-chase analysis showed that the stability of p53 increased in HHV-6-infected cells. In addition, the ubiquitination of p53 decreased after infection, indicating that the stability of p53 was increased through deubiquitination. We showed by confocal microscopy that the additional p53 mainly localized to the cytoplasm and that p53 was retained in the cytoplasm even after UV irradiation, but that it translocated into the nucleus in mock-infected cells. Furthermore, DNA fragmentation analysis, a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assay and annexin V staining showed that infected cells were resistant to UV-induced apoptosis. These results lead us to propose that HHV-6 has a mechanism for retaining p53 within the cytoplasm and protects the infected cells from apoptosis.

Apoptosis↗
PubMed2004

Human herpesvirus 6 immediate-early 2 protein interacts with heterogeneous ribonucleoprotein K and casein kinase 2.

Human herpesvirus 6 (HHV-6) immediate-early (IE) 2 protein (IE2) may play important but incompletely defined roles during infection. We used yeast two-hybrid screening to detect proteins interacting with HHV-6 IE2, and found heterogeneous nuclear ribonucleoprotein K (hnRNP K) and the beta subunit of casein kinase 2 (CK2beta) specifically interacted with HHV-6 IE2. The interactions were confirmed by GST pull-down assay, coimmunoprecipitation, and colocalization studies. These findings indicate that the HHV-6 IE2 protein interacts with hnRNP K and CK2, and these interactions may affect viral and cellular RNA transcription and translation in viral replication.

Casein Kinase II↗
PubMed2003

Detection of a gene cluster that is dispensable for human herpesvirus 6 replication and latency.

The U3-U7 gene cluster of human herpesvirus 6 (HHV-6) was replaced with an enhanced green fluorescent protein-puromycin gene cassette containing the cytomegalovirus major immediate-early promoter. Neither viral replication in T cells nor latency and reactivation in macrophages was impaired. During HHV-6 latency, the cytomegalovirus promoter used the transcription start sites employed in cytomegalovirus latency.

Cytomegalovirus↗
PubMed2003

Recognition of a novel stage of betaherpesvirus latency in human herpesvirus 6.

Latency-associated transcripts of human herpesvirus 6 (H6LTs) (K. Kondo et al. J. Virol. 76:4145-4151, 2002) were maximally expressed at a fairly stable intermediate stage between latency and reactivation both in vivo and in vitro. H6LTs functioned as sources of immediate-early protein 1 at this stage, which up-regulated the viral reactivation.

Adolescent↗