Search PubMed⌕ Search

Biomedical subjects

K Baba

Publications and source records attributed to K Baba.

At least 73 records · Page 4Linked to original sources
PubMed2000

[Measurement of formaldehyde-specific IgE antibodies in adult asthmatics].

Formaldehyde (FA) is known to be a potent contact sensitizer eliciting dermatitis or bronchial asthma in occupational settings. However, several pieces of recent evidence indicate that FA is a participant of indoor air pollution even at home and that it may be one of the causative agents for the sick-house syndrome. In the present study, we examined whether production of FA-specific IgE antibody (FA-IgE) occurred in adult chronic asthmatics or not. We randomly selected 80 adult asthmatics, and obtained blood sampling under the condition where the symptoms were well controlled. We measured FA-IgE, eosinophil count and serum concentration of eosinophil cationic protein (sECP), and also measured lung functions (FEV1%, %VC, V25/HT). We found that FA-IgE was positive in two patients (33-year-old female and 56-year-old male), while negative (less than 0.35 UA/ml) in the others. State of asthma was severe in the female patient, while mild intermittent in the male patient. In the female patient, the total IgE titer and the FA-IgE titer were 181 IU/ml and 0.81 UA/ml, respectively, and there was no occupational environments concerning FA. In the male patient, both the total IgE and the FA-IgE titer were quite high (8400 IU/ml and 2.99 UA/ml, respectively). In this case, there was an occupational environment where the adhesive smell was strong. sECP was 44.2 micrograms/l in the female patient, while 4.7 micrograms/l in the male patient. In the present study, IgE-mediated allergy for FA was rare in adult chronic asthmatics, and the FA-IgE titer did not seem parallel to severity or pathophysiological condition in bronchial asthma. But, further development of precise methodology for clinically clarifying FA-mediated mechanisms in allergic disorders, might be still important.

Adult↗
PubMed2000

[A survey of drug utilization in psychiatric hospitals in Japan: comparison of 1973, 1979, and 1993].

This paper investigated the trend in prescription patterns in the treatment of psychiatric inpatients using a database of our 1993 survey as well as reports of surveys conducted by Ito et al. in 1973 and 1979. To make the database of our survey comparable with surveys in 1973 and 1979, we extracted and analyzed 1,164 cases which met the criteria of Ito's survey, requiring that patients were diagnosed as having schizophrenia and were hospitalized for two years or longer. The results were as follows: 1) The most common number of different drugs per patient increased from 4 in 1973 and 1979 to 8 in 1993. That of psychotropics increased from 2 to 5. That of neuroleptics increased from 2 to 3. 2) The most commonly prescribed neuroleptics were haloperidol followed by levomepromazine and chlorpromazine. While the top three neuroleptics had not changed, the mean daily dose of haloperidol rose from 8.4 mg in 1979 to 15.3 mg in 1993.

Databases, Factual↗
PubMed1999

Rat liver in vivo replicative DNA synthesis test for short-term prediction of nongenotoxic (Ames-negative) hepatocarcinogenicity: a collaborative study of the Nongenotoxic Carcinogen Study Group of Japan.

A collaborative study was conducted to evaluate whether a replicative DNA synthesis (RDS) test using the rat liver can detect nongenotoxic (Ames-negative) hepatocarcinogens with three or seven daily administrations at dose-levels effective in long-term bioassays. The assay methods were well-validated by the 14 participants. Of six compounds tested, carbon tetrachloride (50 and 100 mg/kg), clofibrate (125 and 250 mg/kg), diethylstilbestrol (0.125 and 0.25 mg/kg) and urethane (100 mg/kg) gave positive results, methyl carbamate (200 and 400 mg/kg) exerted equivocal effects, and D,L-ethionine (125 mg/kg) failed to elevate RDS. These findings suggest that the RDS test can detect many nongenotoxic rat hepatocarcinogens with short-term administration at dose-levels used in long-term bioassays.

Animals↗
PubMed1999

Thickness of fibrous capsule after implantation of hydroxyapatite in subcutaneous tissue in rats.

The present study evaluates in rats the histomorphometrical thickness of fibrous capsules that surround hydroxyapatite (HA) disks after implantation. HA disks were implanted into the subcutaneous tissue of 79 rats for 1 day to 20 months. Decalcified histological sections stained with hematoxylin and eosin were examined. Fibrous capsule thickness (FCT) was measured using an objective micrometer. On the fourteenth day, primary fibrous capsules formed around implants. From that time point FCT increased with time of implantation. Within a given sample, FCT differed from one portion of the fibrous capsule to another, depending on which site faced the disks. FCT was thickest at the upper and lower portions of the disks, thinner at the lateral portions, and thinnest at the upper and lower ring-shaped portions. Two possible explanations for the above findings are discussed in this paper: (1) The area of contact between disk and tissue differs. (2) Chemical stimulation of implanted material caused by demineralization and remineralization may result from the varying thicknesses of fibrous capsules. FCT from upper and lower portions of HA disks increased by over 200% in the first 10 months and steadily increased about 20% over the next 10 months. Many studies have concluded that HA is useful for reconstructive surgery, so the long-term effects of FCT need further study.

Animals↗
PubMed1999

Diagnostic problems of evaluating vertebral metastasis from breast carcinoma with a higher degree of malignancy.

BACKGROUND: Bone metastases from breast carcinoma are frequently observed as postoperative pathologic conditions; however, in many cases, diagnosis and treatment are difficult. Although most diagnoses of bone metastases are made by plain radiography (X-P) or bone scintigraphy, the use of magnetic resonance imaging (MRI) has enabled detailed imaging of foci, and many more lesions have become detectable. In the current study, the authors evaluated the relation between the diagnosis of bone metastases of breast carcinoma and clinicopathologic factors, especially those of proliferative activity and effects of treatment. METHODS: The subjects consisted of 51 breast carcinoma patients (mean age, 51.2 years) with vertebral metastases diagnosed by plain radiography, bone scintigraphy, or MRI. Twenty-eight of the 51 patients were premenopausal and 27 of the 51 had bone metastases only. The patients were classified into the following groups: Group A, 24 patients who showed similar findings in plain radiography, bone scintigraphy, and MRI; Group C, 14 who showed no abnormalities on radiography or bone scintigraphy but whose lesions were diagnosed by MRI only; and Group B, 13 patients with findings intermediate between Groups A and C. The proliferative activity of tumors was evaluated by determining the level of DNA polymerase alpha. RESULTS: Regarding the relation to clinicopathologic factors, a significant number of patients with estrogen receptor (ER) negative tumors who had a high level of DNA polymerase alpha, short disease free intervals (DFI), and metastases to other organs were included in Group C. Prognoses of patients in Group C were poor. CONCLUSIONS: For the diagnosis of breast carcinoma with bone metastasis, different correlations were noted among the various biologic characteristics, such as ER status and proliferative activity. That is, bone scintigraphy sufficiently reflected foci in patients with ER positive tumors or tumors with low proliferation, whereas bone scintigraphy was false-negative in patients with ER negative or highly proliferative tumors, showing that MRI was useful in diagnosing such patients. Therefore, consideration of malignant features, such as proliferative activity and ER status, is believed necessary during the postoperative follow-up of breast carcinoma patients.

Adult↗
PubMed1999

Apoptosis in breast cancer and its relationship to clinicopathological characteristics and prognosis.

BACKGROUND AND OBJECTIVES: Apoptosis is essential to maintain homeostasis in living organisms and occurs in a variety of tissues in response to both physiological and pathological stimuli. In breast cancer, most cytotoxic drugs and hormonal treatments induce apoptosis. We studied the relationships between apoptosis and clinicopathological variables or prognosis in 143 patients with operable breast cancer. METHODS: Apoptosis was numerically graded in 5 consecutive 40x high-power fields (HPF) of hematoxylin-eosin (H&E) stained sections, since we showed that there was a significant correlation of H&E staining with terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining. RESULTS: The average number of apoptotic cells was 19.9 (0 approximately 168)/5 HPF, and cases were classified into 3 groups based on the number of apoptotic cells/5HPF: 0 to 10, 11 to 30, and 31+. The level of apoptosis increased with increasing size of the tumor, and apoptosis was rarely seen in tumors with positive ER or lower proliferative activity, as assessed by DNA polymerase alpha. As shown by DNA content analysis, apoptotic cells were observed more frequently in tumors with low G1 and high S-phase fractions. In addition, apoptosis was correlated with overexpression of p53 and poor prognosis. Although apoptosis did not correlate with EIC (extensive intraductal component) status, tumors with comedo component had higher values of apoptosis than those without comedo component. CONCLUSIONS: In breast cancer, apoptosis might reflect biological behavior, namely a higher degree of biological aggressiveness and unfavorable prognosis.

Adult↗
PubMed1999

Thin sol-gel-derived silica coatings on dental pure titanium casting.

The sol-gel dipping process, in which liquid silicon alkoxide is transformed into a solid silicon-oxygen network, can produce a thin film coating of silica (SiO(2)). The features of this method are high homogeneity and purity of the thin SiO(2) film and a low sinter temperature, which are important in the preparation of coating films that can protect metallic ion release from the metal substrate and prevent attachment of dental plaque. We evaluated the surface properties of dental pure titanium casting coated with a thin SiO(2) or SiO(2)/F-hybrid film by the sol-gel dipping process. The metal specimens were pretreated by dipping in isopropylalcohol solution containing 10 wt% 3-aminopropyl trimethoxysilane and treated by dipping in the silica precursor solution for 5 min, withdrawal at a speed of 2 mm/min, air-drying for 20 min at room temperature, heating at 120 degrees C for 20 min, and then storing at room temperature. Both SiO(2) and SiO(2)/F films bonded strongly (above 55 MPa) to pure titanium substrate by a tensile test. SiO(2(-)) and SiO(2)/F-coated specimens immersed in 1 wt% of lactic acid solution for two weeks showed significantly less release of titanium ions (30. 5 ppb/cm(2) and 9.5 ppb/cm(2), respectively) from the substrate than noncoated specimens (235.2 ppb/cm(2)). Hydrophobilization of SiO(2(-)) and SiO(2)/F-coated surfaces resulted in significant increases of contact angle of water (81.6 degrees and 105.7 degrees, respectively) compared with noncoated metal specimens (62.1 degrees ). The formation of both thin SiO(2) and SiO(2)/F-hybrid films by the sol-gel dipping process on the surface of dental pure titanium casting may be useful clinically in enhancing the bond strength of dental resin cements to titanium, preventing titanium ions release from the substrate, and reducing the accumulation of dental plaque attaching to intraoral dental restorations.

Adhesiveness↗
PubMed1999

Silica coatings formed on noble dental casting alloy by the sol-gel dipping process.

The sol-gel dipping process, in which liquid silicon alkoxide is transformed into the solid silicon-oxygen network, can produce a thin film coating of silica (SiO2). The features of this method are high homogeneity and purity of the thin SiO2 film and a low sinter temperature, which are important in preparation of coating films that can protect from metallic ion release from the metal substrate and prevent attachment of dental plaque. We evaluated the surface characteristics of the dental casting silver-palladium-copper-gold (Ag-Pd-Cu-Au) alloy coated with a thin SiO2 film by the sol-gel dipping process. The SiO2 film bonded strongly (over 40 MPa) to Ti-implanted Ag-Pd-Cu-Au alloy substrate as demonstrated by a pull test. Hydrophobilization of Ti-implanted/SiO2-coated surfaces resulted in a significant increase of the contact angle of water (80.5 degrees) compared with that of the noncoated alloy specimens (59.3 degrees). Ti-implanted/SiO2-coated specimens showed the release of many fewer metallic ions (192 ppb/cm2) from the substrate than did noncoated specimens (2,089 ppb/cm2). The formation of a thin SiO2 film by the sol-gel dipping process on the surface of Ti-implanted Ag-Pd-Cu-Au alloy after casting clinically may be useful for minimizing the possibilities of the accumulation of dental plaque and metal allergies caused by intraoral metal restorations.

Adhesiveness↗
PubMed1999

Severe aplastic anemia associated with human parvovirus B19 infection in a patient without underlying disease.

Human parvovirus B19 (B19 virus) infection is known to induce aplastic crisis in patients with hemolytic anemia. In healthy subjects, B19 infection may sometimes cause mild pancytopenia, but these changes are transient and recovery is spontaneous. We report the first case of aplastic anemia in a previously healthy boy without any underlying diseases, following asymptomatic infection with the B19 virus. Laboratory examination initially showed thrombocytopenia, mild leukopenia in the peripheral blood, and severe hypoplastic bone marrow. Since pancytopenia developed and worsened progressively, immunosuppressive therapy was given, resulting in a complete remission. Despite the lack of an infectious prodrome, serological and histological analysis revealed an underlying infection with the B19 virus. Thus, B19 virus infection must be considered one of the causes of aplastic anemia in patients without underlying hemolytic anemia and an apparent episode of the viral infection.

Adolescent↗
PubMed1999

Wear of alumina ceramics prosthesis.

To investigate the process of wear in the total knee prosthesis consisting of alumina ceramics (Al-ceramics) and ultra-high molecular weight polyethylene (UHMWP) in vivo, we observed the fine structures of the articular surface of the prostheses used for four patients with osteosarcoma of the distal femur. We also examined the wear debris in the surrounding soft tissues. The prostheses were extracted at autopsy between 13 and 48 months after surgery. An increase of pores, indicating where Al-ceramics grains fell off, and many streaks on the UHMWP running parallel to the gliding direction of the joint were observed on the articular surface. The streaks had similar widths to the Al-ceramics grains. Al-ceramics debris was detected in the soft tissues around the joint mixed with UHMWP debris. We concluded that the wear of UHMWP in Al-ceramics prosthesis was promoted by interposition of Al-ceramics debris.

Adolescent↗
PubMed1999

Genotypes of TT virus (TTV) compared between liver disease patients and healthy individuals using a new PCR system capable of differentiating 1a and 1b types from others*.

TT virus (TTV) lacks obvious pathogenicity; almost all of the infected hosts are symptom-free. A possibility remains, however, that certain strains can cause liver disease while most others are non-pathogenic. Genotypes 1 a and 1 b have been proposed to contain such pathogenic strains. To test this possibility, we constructed a PCR system capable of detecting TTV of the 1 a and 1 b genotypes differentially from the other genotypes, and compared the frequencies of these genotypes between patients with liver disease of unknown etiology (n=42) and healthy individuals (n=50). The assay comprised 3 steps: i) PCR to amplify a 3.2-kb fragment using universal primers; ii) 2nd-round PCR, starting from the 3.2-kb amplicon, for a approximately 280-nt fragment by use of genotype 1-specific primers; and iii) digestion of the approximately 280-nt amplicon with MboI and BanI to discriminate between 1 a and 1 b. Eventually, 40 (95%) of the patients and 47 (94%) of the controls were positive for the 3.2-kb amplicon, and the 1 a, 1 b, 1 a+1 b, and non-1 genotypes of TTV were found in 2 (5%) vs 4 (9 percent), 5 (13%) vs 4 (9%), 1 (3%) vs 1 (2%) and 32 (80%) vs 38 (81%) of the 40 patients and 47 controls, respectively: the distribution was almost identical between the two groups. The hypothesis that the genotype 1 of TTV may be more closely associated with liver disease than other genotypes was not supported by this study.

Base Sequence↗
PubMed1999

Sixty-eight years of experimental occlusal interference studies: what have we learned?

STATEMENT OF PROBLEM: Understanding is needed regarding the effect that occlusal interferences have on the teeth, periodontium, and especially on jaw function. PURPOSE: This article summarizes research in which experimental occlusal interferences have been placed on the teeth of animals and human volunteers. MATERIAL AND METHODS: Data from 18 human and 10 animals studies were reviewed. Experimental occlusal interferences were grouped into those that alter intercuspal position and those contacting on lateral jaw movement only. The outcome of these interferences were analyzed according to their local pulpal-periodontal, jaw function, or bruxism effects. RESULTS: Experimental occlusal interferences in maximum intercuspation had a deleterious effect on periodontal and pulpal tissues of the affected tooth; sometimes this produces a disruption of smooth jaw function and occasionally jaw muscle pain and clicking. Experimental occlusal interferences that contact only in a lateral jaw movement are infrequently harmful to jaw function. Furthermore, no reliable evidence demonstrates that occlusal interferences can cause nocturnal bruxism, or stop it. CONCLUSION: Transient local tooth pain, loosening of the tooth, a slight change in postural muscle tension levels, chewing stroke patterns, and sometimes a clicking joint can be induced by an experimental occlusal interference. Because such findings are present in relatively asymptomatic patients, these data do not prove that occlusal interferences are causally related to a chronic jaw muscle pain or temporomandibular joint dysfunction problems.

Animals↗
PubMed1999

Effects of daphnodorin A, daphnodorin B and daphnodorin C on human chymase-dependent angiotensin II formation.

We investigated whether daphnodorin A, daphnodorin B and daphnodorin C inhibited human chymase-dependent angiotensin II-forming activity. Although the structures of these compounds are very similar, daphnodorin A completely inhibited angiotensin II formation generated by chymase, while daphnodorin B partially inhibited and daphnodorin C did not. On the other hand, these daphnodorins did not affect angiotensin converting enzyme-dependent angiotensin II formation. Furthermore, these daphnodorins did not inhibit purified human tryptase, which, like chymase, is contained in mast cells. Therefore, daphnodorin A, but not daphnodorin B and daphnodorin C, may specifically inhibit the chymase-dependent angiotensin II formation, and such differences between inhibitory effects of these compounds to human chymase may be useful for the development of human chymase inhibitor.

Adult↗
PubMed1999

Serological detection of hepatitis B virus genotypes by ELISA with monoclonal antibodies to type-specific epitopes in the preS2-region product.

An ELISA was developed for serological determination of the six genotypes of hepatitis B virus (HBV) designated A, B, C, D, E, and F. Monoclonal antibodies were raised against genotype-specific epitopes in the preS2-region product, and labeled with horseradish peroxidase. Hepatitis B surface antigen (HBsAg) in sera was captured by immobilized antibodies against the common determinant, and evaluated for reactivity with genotype-specific monoclonal antibodies labeled with the enzyme. Serological genotyping was in complete accord with genotypes determined by S-gene sequences in a panel of 68 sera containing HBV/HBsAg of different genotypes. Of 514 sera with HBsAg from Japan, 507 (98.6%) were genotyped serologically: genotype A was identified in 24 (4.7%); B in 196 (38.1%); C in 282 (54.9%); D in 2 (0.4%); and F in 3 (0.6%). There were no sera containing HBV of genotype E. Likewise, 425 of 446 (95.3%) sera with HBsAg from Brazil, China, India, Indonesia, Kenya, Korea, Nepal, Papua New Guinea, the Philippines, and Thailand were classified into A (25.6%), B (24.2%), C (33.9%), and D (11.7%) genotypes; there were no sera with HBsAg of genotype E or F among them. Some sera unclassifiable by ELISA revealed mixed infection with HBV of distinct genotypes, or contained HBsAg deprived of genotype-specific epitopes by point mutations. The ELISA would be useful for large-scale surveys, because it allows serological detection of HBV genotypes without sequencing nucleotides.

Amino Acid Sequence↗
PubMed1999

Ethnic difference in the prevalence of monoclonal B-cell proliferation in patients affected by hepatitis C virus chronic liver disease.

BACKGROUND/AIM: In previous studies we demonstrated that all patients affected by HCV-positive type II mixed cryoglobulinaemia have a monoclonal B-cell population in peripheral blood mononuclear cells, and that a large fraction of HCV-infected patients develop a monoclonal B-cell expansion, even in the absence of dosable serum cryoglobulins. However, the prevalence of Type II mixed cryoglobulinaemia in HCV-infected individuals seems to be high in Italy, whereas it is very low in Japan. This study was performed to investigate whether there are ethnic differences in the prevalence of asymptomatic HCV-associated monoclonal B-cell expansions. METHODS: Forty-four Japanese patients affected by HCV-positive chronic liver disease (two healthy carriers, 31 chronic hepatitis and 11 cirrhosis) were compared with a group of 60 Italian patients (one healthy carrier, 49 chronic hepatitis, and 10 cirrhosis) without dosable levels of cryoglobulins. The monoclonality of peripheral blood mononuclear cells was investigated by RT/PCR analysis of Immunoglobulin gene rearrangements. Liver function tests, rheumatoid factor, cryocrit level, anti-HCV antibodies, HCV-RNA, and HCV genotype were performed according to standard methodology. RESULTS: A B-cell monoclonal population was found in 26% of Italian patients, whereas all Japanese patients were negative. No correlation was found between B-cell monoclonality and severity of liver disease, length or source of the infection, HCV genotype, sex, clinical and biochemical parameters. CONCLUSIONS: This study indicates that a monoclonal B-cell proliferation in peripheral blood mononuclear cells is common in HCV infection, but only in Italy, whereas it is absent in Japan. This explains the very low prevalence of Type II mixed cryoglobulinaemia in HCV-positive Japanese subjects, and suggests that HCV is able to determine a B-cell expansion only in the presence of, presently undetermined, host factors.

Asian People↗
PubMed1999

The amino acid sequence of a lamprey (Entosphenus japonicus) liver fatty acid-binding protein identified its close relationship to cardiac fatty acid-binding proteins of Mammalia.

Fatty acid-binding proteins (FABPs) constitute a large, tissue-specific multigene family in animals. While liver FABPs of Aves, Reptilia, and Amphibia are close homologs of mammalian liver FABPs, the shark liver protein belongs to the mammalian heart FABP subfamily. We purified an FABP from the liver of lamprey, Entosphenus japonicus, by gel filtration and anion-exchange chromatography. Amino acid sequences determined for lysyl endopeptidase peptides covered nearly the entire molecule except for N- and C-terminal short segments. Examination of the phylogenetic relationship from the sequence identified the lamprey liver protein as a member of mammalian heart-type FABPs. Since livers of bony fish contain both hepatic and cardiac FABPs, expression of the FABP gene in the vertebrate liver appears to change from the heart-type to liver-type within Pisciformes, with bony fish being in a transition stage. This may be related to the evolutionary and physiological divergence of liver function and lipid metabolism of these lower vertebrates.

Amino Acid Sequence↗
PubMed1999

Early axonal and glial pathology in fetal sheep brains with leukomalacia induced by repeated umbilical cord occlusion.

We conducted a chronic preparation experiment involving near term fetal sheep to evaluate the contribution of umbilical cord occlusion to fetal brain injury. In experimental groups (n = 11), complete cord occlusion for 3 min followed by 5 min release, repeated 5 times were performed at 3 days after initial surgery. Instrumental cases without cord occlusion (n = 3) and uninstrumental twins (n = 6) were also examined as controls. Multiple necrotic foci predominantly in the periventricular white matter were found in the fetal brains examined at 1-3 days after cord occlusion. To estimate the contribution of early axonal and glial reaction to brain injury the following immunohistochemical study was performed. In the lesions, coagulation necrosis, axonal swelling and microglial activation were demonstrated with amyloid precursor protein or ionized calcium binding adapter molecule 1 immunohistochemistry. The induction of tumor necrosis factor alpha and inducible nitric oxide synthase were also detected immunohistochemically in the microglia at 1 and 3 days after cord occlusion. In contrast, the reaction of glial fibrillary acidic protein positive astrocytes was faint at 1 day after occlusion, but the induction of cyclooxygenase-2 was observed. These findings suggest the glial reaction of cytokines and free radicals induced by fetal hypoxia may contribute to the occurrence of brain injury.

Amyloid beta-Protein Precursor↗