Biomedical subjects

K Nanba

Publications and source records attributed to K Nanba.

At least 19 recordsLinked to original sources

PubMed2004

Analysis of facultative lithotroph distribution and diversity on volcanic deposits by use of the large subunit of ribulose 1,5-bisphosphate carboxylase/oxygenase.

A 492- to 495-bp fragment of the gene coding for the large subunit of the form I ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) (rbcL) was amplified by PCR from facultatively lithotrophic aerobic CO-oxidizing bacteria, colorless and purple sulfide-oxidizing microbial mats, and genomic DNA extracts from tephra and ash deposits from Kilauea volcano, for which atmospheric CO and hydrogen have been previously documented as important substrates. PCR products from the mats and volcanic sites were used to construct rbcL clone libraries. Phylogenetic analyses showed that the rbcL sequences from all isolates clustered with form IC rbcL sequences derived from facultative lithotrophs. In contrast, the microbial mat clone sequences clustered with sequences from obligate lithotrophs representative of form IA rbcL. Clone sequences from volcanic sites fell within the form IC clade, suggesting that these sites were dominated by facultative lithotrophs, an observation consistent with biogeochemical patterns at the sites. Based on phylogenetic and statistical analyses, clone libraries differed significantly among volcanic sites, indicating that they support distinct lithotrophic assemblages. Although some of the clone sequences were similar to known rbcL sequences, most were novel. Based on nucleotide diversity and average pairwise difference, a forested site and an 1894 lava flow were found to support the most diverse and least diverse lithotrophic populations, respectively. These indices of diversity were not correlated with rates of atmospheric CO and hydrogen uptake but were correlated with estimates of respiration and microbial biomass.

Bacteria, Aerobic↗

PubMed2001

Recovery of infectious human parainfluenza type 2 virus from cDNA clones and properties of the defective virus without V-specific cysteine-rich domain.

A full-length cDNA clone was constructed from the genome of the human parainfluenza type 2 virus (hPIV2). First, Vero cells were infected with recombinant vaccinia virus expressing T7 RNA polymerase, and then the plasmid encoding the antigenome sequence was transfected into Vero cells together with polymerase unit plasmids, NP, P, and L, which were under control of the T7 polymerase promoter. Subsequently, the transfected cells were cocultured with fresh Vero cells. Rescue of recombinant hPIV2 (rPIV2) from cDNA clone was demonstrated by finding the introduced genetic tag. As an application of reverse genetics, we introduced one nucleotide change (UCU to ACU) to immediate downstream of the RNA-editing site of the V gene in the full-length hPIV2 cDNA and were able to obtain infectious viruses [rPIV2V(-)] from the cDNA. The rPIV2V(-) possessed a defective V protein that did not have the unique cysteine-rich domain in its carboxyl terminus (the V-protein-specific domain). The rPIV2V(-) showed no growth in CV-1 and FL cells. Replication of the rPIV2V(-) in these cells, however, was partially recovered by adding anti-interferon (IFN)-beta antibody into the culture medium, showing that the rPIV2V(-) is highly sensitive against IFN and that no growth of rPIV2V(-) in CV-1 and FL cells is mainly due to its hypersensitivity to endogenously produced IFN. These findings indicate that the V-protein-specific domain of hPIV2 is related to IFN resistance. On the other hand, the rPIV2V(-) efficiently replicated in Vero cells, which are known as a IFN-non-producers. However, the virus yields of rPIV2V(-) in Vero cells were 10- to100-fold lower than those of control rPIV2, although syntheses of the viral-specific proteins and their mRNAs in rPIV2V(-)-infected Vero cells were augmented up to 48 p.i. in comparison with those of rPIV2. Furthermore, the rPIV2V(-) virions showed anomalous in size as compared with rPIV2 virions. These results suggest that the V protein plays an important role in the hPIV2 assembly, maturation, and morphogenesis.

Animals↗

PubMed2001

Cross-talk between RANKL and FRP-1/CD98 Systems: RANKL-mediated osteoclastogenesis is suppressed by an inhibitory anti-CD98 heavy chain mAb and CD98-mediated osteoclastogenesis is suppressed by osteoclastogenesis inhibitory factor.

The two pathways to osteoclastogenesis, RANKL-mediated and CD98-mediated osteoclastogenesis, have recently been reported. RANKL, OCIF, and TIMP-3 mRNAs are not found in monocytes freshly isolated or incubated with anti-FRP-1/CD98hc antibody. RANK, TACE, and M-CSF mRNAs can be detected in these cells. Interestingly, the expressed amount of RANK mRNA increases by cultivation of monocytes with anti-CD98hc antibody and maximal expression is observed in osteoclast-like cells. CD98-mediated cell aggregation and multinucleated giant cell formation are blocked by OCIF. OCIF also suppressed the CD98-mediated induction of Sp1 and c-src mRNAs in monocytes. Soluble RANK shows no effect on CD98-mediated cell aggregation and multinucleated giant cell formation. When blood monocytes were incubated with RANKL and M-CSF, c-src and Sp1 mRNAs were first found in blood monocytes incubated with these cytokines for 7 days. On the contrary, c-src mRNA could be detected 3 h after treatment of blood monocytes with anti-CD98hc mAb. LAT-1 mRNA was not found, and the expression levels of Y(+)LAT-1 and Y(+)LAT-2 mRNAs were not changed in monocytes stimulated without or with anti-CD98hc mAb or RANKL and M-CSF. An inhibitory mAb directed against CD98hc, HBJ 127, shows a suppressive effect on RANKL-mediated cell aggregation and cell fusion. Thus, there is cross-talk between these two pathways.

Antibodies, Monoclonal↗

PubMed2001

Palatal radicular multigrooves associated with severe periodontal defects in maxillary central incisors.

BACKGROUND: This case report describes a rare condition of palatal radicular multigrooves on teeth 11 and 21 with severe periodontal defects and the findings at 3-year follow-up. METHOD: Radiculoplasty using hand curettes and rotary burs were used to remove the multigrooves on the root surfaces and change the wrinkled root form to the relatively flat and smooth normal root morphology. Minor tooth movement and frenotomy were performed for a diastema between teeth 11 and 21. Supportive periodontal therapy started immediately after completion of the active treatment. RESULTS: Improved healthy periodontal tissues and adequate plaque control have been maintained.

Adult↗

PubMed2001

Long-term follow-up study on patients with sleep apnea syndrome.

We did a 5-year follow-up study on sleep apnea syndrome (SAS)-related symptoms and respiratory disorder variables on 109 patients. At follow up, SAS-related symptoms were improved in a significantly higher percentage of the treatment success group than the treatment failure group. A significant deterioration of the respiratory disorder variables was recognized only in the patients 40-60 years of age. These results indicate that treatment effect for SAS might be maintained in the long term and that the natural evolution of the disorder might be prominent in middle-aged patients.

Acetazolamide↗

PubMed2001

P300 abnormalities in patients with severe sleep apnea syndrome.

We investigated the mechanism of abnormal P300 findings in the patients with severe sleep apnea syndrome (SAS). Compared with controls, SAS patients showed significantly longer latency of P300. Not the mean sleep latency in multiple sleep latency test but the percentage of total periods in which percentage desaturation time fell below 90% to total sleep time correlated with P300 latency in the patients. During nasal CPAP treatment, P300 latency was significantly shortened in the patients under 45 years, while the elderly patients did not show statistical change. We speculated that P300 latencies might be prolonged due to nocturnal hypoxia with SAS and the abnormality might be irreversible, especially in elderly patients.

Adult↗

PubMed2001

Aggregated occurrence of sleep apnea syndrome in a family.

We experienced a family in whom sleep apnea syndrome (SAS) was recognized in six members and habitual snoring in seven members among 26 subjects of four generations. In all members with snoring, the disorder was noticed before the age of 20. Hypercapnic response study showed normal findings, and ultrafast magnetic resonance image of the upper airway revealed that the obstruction of the upper airway occurred at the velopharyngeal portion during apneic episodes in all SAS-afflicted subjects. In this family, the similar craniofacial structural abnormalities were thought to cause the aggregated occurrences of the disorders at young ages, and obesity was regarded as a contributor for the aggravated symptoms.

Adult↗

PubMed2001

Relationships of serum levels of insulinlike growth factors with indices of bone metabolism and nutritional conditions in hemodialysis patients.

Insulinlike growth factor (IGF) I and IGF-II are synthesized in osteoblasts and stimulate proliferation, differentiation, and matrix synthesis in these cells. There is some evidence that IGFs act on bone cells not only by paracrine but also by endocrine pathways, suggesting that circulating IGFs may be of importance for the regulation of bone metabolism. On the other hand, the serum IGF-I level is also thought to be a good indicator of the nutritional conditions in hemodialysis patients. The present study was performed to analyze the correlations of circulating levels of IGF-I, IGF-II, IGF-binding protein (IGFBP) 1 and IGFBP-3 with biochemical markers of bone metabolism and parameters of the urea kinetic model which reflect nutritional conditions in hemodialysis patients. We also examined the differences between these relationships in male and female patients on hemodialysis. Sixty-two hemodialysis patients, 36 men (male group) and 26 women (female group), were included in this study. We measured the serum levels of IGF-I, IGF-II, IGFBP-1, and IGFBP-3. The bone mineral content (BMC) of the radius was measured by dual-energy X-ray absorptiometry. We calculated Kt/V, protein catabolic rate, and percent creatinine generation rate (%CGR). We also examined the relationships between serum levels of IGFs and BMC and the parameters of the urea kinetic model. It was found that the serum levels of IGF-I in the hemodialysis patients were almost the same as those in the control group. However, the serum levels of IGF-II, IGFBP-1, and IGFBP-3 in the hemodialysis patients were significantly higher than those in the control group. In the male group, the serum IGF-I levels showed a significant correlation with both serum intact parathyroid hormone levels and BMC, but no significant correlations between these indices were found in the female group. The serum levels of both IGF-I and IGF-II showed significant correlations with %CGR in the male group, but not in the female group. Stepwise multiple regression analysis was performed to clarify the relationship between serum levels of IGFs and BMC or %CGR. It was found that age, hemodialysis duration, serum intact parathyroid hormone levels, and sex were independent factors associated with BMC. The %CGR was associated independently with serum levels of IGF-I, and IGF-II and with the presence of diabetes mellitus. In conclusion, it is thought that serum levels of IGF-I and IGF-II can be used as indices of nutritional conditions in hemodialysis patients. However, the serum IGF-I level cannot be used as a marker of bone metabolism in hemodialysis patients.

Biomarkers↗

PubMed2001

Effects of guided bone regeneration with non-resorbable and bioabsorbable barrier membranes on osseointegration around hydroxyapatite-coated and uncoated threaded titanium dental implants placed into a surgically-created dehiscence type defect in rabbit tibia: a pilot study.

The purpose of this study was to evaluate the effects of guided bone regeneration (GBR) with either a non-resorbable (ePTFE) or bioabsorbable barrier membrane (RSLT) on osseointegration and extent of bone formation around hydroxyapatite-coated (HA) and uncoated threaded titanium (Ti) dental implants placed into surgically-created dehiscence type defects in rabbit tibia. A dehiscence type bone defect, approximately 3 mm in width and height was surgically created on the outer surface of the bone in each tibia of 9 rabbits. For the conventional group, either a HA or a Ti implant was then placed at this site. After the same procedure was performed as in the conventional group, the implant site of the GBR group was covered with either an ePTFE or a RSLT. After 4 months, the rabbits were sacrificed. Specimens were prepared and examined histometrically. It was found that the mean percentage of osseointegration tended to increase in HA compared to Ti implants, both with and without membranes. There was a tendency that the extent of newly regenerated bone was higher in the GBR group than that in the conventional group.

Absorbable Implants↗

PubMed2001

[A case of post-tuberculosis chronic empyema with effective low-dose, long-term clarithromycin administration].

A 78-year-old woman with post-tuberculosis chronic empyema who underwent unsuccessful decortication in July 1993, was admitted to our hospital in November 1994 because of M. tuberculosis in her sputum. One month after anti-tuberculosis treatment, the M. tuberculosis disappeared from the sputum, but a pleurocutaneous fistula that exuded abundant bloody pus containing Pseudomonas aeruginosa persisted in the area of chronic empyema. In July 1997, 200 mg of clarithromycin (CAM) was administered daily; 21 months later, the pus and pleurocutaneous fistula had disappeared. Post-tuberculosis chronic empyema with a fistula is generally an intractable condition that necessitates surgery. In this case, the empyema did not improve during the 4 years after the surgery. However, low-dose, long-term CAM administration brought about a disappearance of pus from the fistula and closure of the empyema spaces.

Aged↗

PubMed2000

Familial interstitial nephritis with progressive renal failure.

We describe a 53-year-old woman with chronic interstitial nephritis and asymptomatic impairment of renal function. Seven members of her family were suffering from renal failure and underwent hemodialysis. At the time of their hospital admissions, they had shown evidence of end-stage renal failure at 40 to 50 years of age. Lack of proteinuria, hematuria, hypertension, hyperuricemia, hearing loss, and visual impairment were present before the deterioration of the renal function. Renal biopsy of the presented case indicated chronic interstitial nephritis without glomerular basement membrane abnormalities. Progressive decline of renal function and the inheritance pattern of autosomal dominance in this family suggested the diagnosis of familial interstitial nephritis.

Female↗

PubMed2000

Response of atmospheric methane consumption by maine forest soils to exogenous aluminum salts.

Atmospheric methane consumption by Maine forest soils was inhibited by additions of environmentally relevant levels of aluminum. Aluminum chloride was more inhibitory than nitrate or sulfate salts, but its effect was comparable to that of a chelated form of aluminum. Inhibition could be explained in part by the lower soil pH values which resulted from aluminum addition. However, significantly greater inhibition by aluminum than by mineral acids at equivalent soil pH values indicated that inhibition also resulted from direct effects of aluminum per se. The extent of inhibition by exogenous aluminum increased with increasing methane concentration for soils incubated in vitro. At methane concentrations of >10 ppm, inhibition could be observed when aluminum chloride was added at concentrations as low as 10 nmol g (fresh weight) of soil(-1). These results suggest that widespread acidification of soils and aluminum mobilization due to acid precipitation may exacerbate inhibition of atmospheric methane consumption due to changes in other parameters and increase the contribution of methane to global warming.

Aluminum Compounds↗

PubMed2000

[Epidemiology and geo-pathology of malignant lymphomas with special emphasis on Japanese lymphomas].

The descriptive epidemiology and geo-pathology of malignant lymphomas have been hampered by the absence of a unified classification. Recent proposal of the REAL classification which will soon become the WHO classification is a significant step toward better understandings of the epidemiology of this interesting neoplasia. Worldwide epidemic of non-Hodgkin's lymphoma was discussed with possible relationships to herbicides. General characteristics of Japanese lymphomas as compared to Western lymphomas were described with special emphasis on the correlation between the low incidence rates of follicular lymphomas and Hodgkin's lymphomas.

Female↗

PubMed1999

Treatment of periodic leg movement disorder and restless leg syndrome with talipexole.

In order to investigate the bedtime dose of talipexole, a D2 and alpha2 stimulant, on patients with periodic leg movement disorder (PLMD) and restless leg syndrome (RLS), we made a comparison of polysomnographic findings and subjective symptom ratings before and during 4 weeks of the treatment on five cases with RLS and PLMD. A significant decrease in both the frequencies of periodic leg movements and subjective symptom ratings and significant improvement of sleep composition were recognized during the treatment. We speculate that the combination of the agonistic action of D2 and alpha2 receptor with the drug might not only suppress PLMD and RLS but also improve sleep quality.

Azepines↗

PubMed1999

Osseointegration around titanium screws placed into the areas between guided bone augmented sites compared with osseointegration around guided bone graft augmented sites in rabbit tibia.

The aim of this study was to compare the degree of osseointegration around titanium screws placed into the areas between guided bone augmented sites and guided bone graft augmented sites in 8 Japanese white rabbit tibia. The skin and periosteum were incised and lifted to expose the inner surfaces of both tibia. Eight rabbits were divided into 2 groups: 1) a guided bone augmentation (GBA) group of 2 rabbits, and 2) a guided bone graft augmentation (GBCA) group of 6 rabbits. In the GBA group, the bone marrow was penetrated several times in both tibial bones. Three titanium screws were inserted into the bone so that the top of each screw was 3 mm above the bone surface and covered with an expanded polytetrafluoroethylene membrane (ePTFE). In the GBGA group autogenous cortical bone (10 mm x 10 mm x 1 mm) was taken from the left tibia and grafted on the inner surface of the right tibial bone, titanium screws being similarly inserted. The surgical site was covered by ePTFE. After healing for 2 months, the animals were euthanatized, and the experimental area was prepared for histological investigation. New bone had formed on the surgical sites in the GBA group and grafted bone had survived in the GBGA group, with no sign of infection or membrane exposure. The degree of osseointegration around the screw was 67.6 +/- 11.2% (mean +/- SD) in the GBA group and 78.8 +/- 11.9% in the GBGA group. There was no significant difference between the groups (p = 0.29). The ratio of mineralized bone to bone marrow was 45.7 +/- 6.2% in the GBA group and 64.4 +/- 4.4% in the GBGA group. There was a significant difference between the groups (p < 0.05). Although there was no significant difference for osseointegration around the screw placed into the GBA and GBGA sites, the quality of newly generated bone or grafted bone was quite different. Therefore, we suggest that predictable bone augmentation beyond the bone surface can be achieved by either the GBA or the GBGA procedure with ePTFE. However, it was difficult to conclude which procedure was superior with respect to the osseointegration around the titanium screw.

Animals↗

PubMed1999

gamma delta T-cell lymphoma: a clinicopathologic study of 6 cases including extrahepatosplenic type.

We report 6 cases of gamma delta T-cell lymphoma (GDTL) among 115 peripheral T-cell lymphomas over a 12-year period. All patients exhibited extranodal lymphomas, comprising 3 hepatosplenic, 1 cutaneous, 1 intestinal, and 1 thyroidal lymphoma. Despite therapies, all but 1 patient died of disease within 16 months of diagnosis. The cytologic features of lymphoma cells in 4 of 5 cases examined were very similar: coarsely reticulated nuclear chromatin, multiple small nucleoli, abundant faintly eosinophilic granular cytoplasm, and focal angiocentric proliferation. All 6 lymphomas showed Cd3+CD4-CD8-/+ phenotype. CD56 was positive in 3 cases, 1 of which was also CD16 positive. Perforin and T-cell intracellular antigen-1 were positive in all 5 cases examined. Southern blot analysis revealed clonal gene rearrangements of the T-cell receptor delta-chain gene in all 5 cases examined. Based on these findings, together with a review of the literature, GDTLs seem to have several common lineage-specific features, although clinical presentation and course of GDTL are heterogeneous.

Adolescent↗

PubMed1998

High proportion of missense mutations of the BRCA1 and BRCA2 genes in Japanese breast cancer families.

Mutations in either of two recently identified genes, BRCA1 and BRCA2, are thought to be responsible for approximately two-thirds of all cases of autosomal-dominantly inherited breast cancer. To examine the nature and frequency of BRCA1 and BRCA2 mutations in Japanese families exhibiting a high incidence of breast cancer, we screened 78 unrelated families in this category for mutations of these two genes. Examining the entire coding sequences as well as exon-intron boundaries of both genes by polymerase chain reaction (PCR) single-strand conformation polymorphism (SSCP) and multiplex-SSCP analysis, we identified possible disease-causing alterations in BRCA1 among affected members of 15 families and in BRCA2 in another 14 families. In 15 of those 29 families, the affected individuals carried missense mutations, although most germline mutations reported worldwide have been deletions or nonsense mutations. Our results, indicating that missense mutations of BRCA1 and BRCA2 tend to predominate over frameshifts or nonsense mutations in Japanese breast cancer families, will contribute significantly to an understanding of mammary tumorigenesis in Japan, and will be of vital importance for future genetic testing.

BRCA2 Protein↗

PubMed1998

Gamma/delta T cell lymphoma presenting in the subcutaneous tissue and small intestine in a patient with capillary leak syndrome.

Peripheral T cell neoplasms originating from gamma/delta T cells are rarely reported, despite the development of hepatosplenic lymphoma from gamma/delta T cells. We report a case of multiple generated gamma/delta T cell lymphomas presenting in the subcutaneous tissue and small intestine in a patient with accompanying capillary leak syndrome. The patient, a 43-year-old male presented with remarkable systemic edema, pleural effusion, and ascites. Widespread tumors were evident in the subcutaneous tissue and in the small intestine. A biopsy revealed anaplastic large cell lymphoma in these lesions. Phenotypic examination showed that the neoplastic cells were positive for the surface markers CD3 and TCR delta, but negative for CD4, CD8 and TCR beta. Genomic analysis revealed a clonal rearrangement of the TCR genes encoding the gamma, delta, and beta chains. A polymerase chain reaction analysis of the gene encoding the TCR delta chain showed that the rearrangement occurred between V delta 3 and J delta 1, suggesting that neoplastic cells were generated in the early stages of T cell differentiation.

Adult↗