Biomedical subjects

Y Nakajima

Publications and source records attributed to Y Nakajima.

At least 109 records · Page 6Linked to original sources

PubMed2001

The est1 regulation depends on the oxygen concentration in Acetobacter pasteurianus.

The regulation mechanism for expression of the ethanol inducible esterase gene, est1, was investigated in A. pasteurianus. Deletion analysis of the 5' non coding region of est1 showed that the FNR-binding consensus sequence is important in the induction of est1 by ethanol. Cells grown under oxygen starvation produced esterase-1 in not only the presence but also the absence of ethanol. These results suggest that the induction of est1-expression depends on the oxygen concentration, and the gene may be induced by a FNR-like factor activated by a decrease in the intracellular oxygen concentration.

Alcohol Dehydrogenase↗

PubMed2001

Determination of canine beta2-microgloblin in plasma and urine by enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay was developed for the determination of canine beta2-microglobulin (beta2-m) in plasma and urine. The detectable sensitivity for pure canine beta2-m was 0.05 microg/l and the analytical range was 0.1 to 50 microg/l. The mean analytical recovery when pure canine beta2-m was added to normal plasma was 101.9%. The mean analytical recovery in the urine was 102.1%. The intra-day variation coefficient was 3.1% in plasma, 4.3% in serum and 1.9% in urine. No difference was found between the concentration of beta2-m in plasma and serum (n=17). The concentration of beta2-m in the plasma of normal dogs was 1.82 +/- 0.57 mg/l (n=31). The mean excretion in 24 hr urine collected from normal dogs was 17.6 +/- 9.2 microg/l, 0.22 +/- 0.12 microg/kg of body weight or 14.2 +/- 9.4 microg/g of urine creatinine. The beta2-m creatinine index of random urine samples was 23.5 +/- 16.6 microg/g (n=26). There was a close correlation between the beta2-m creatinine index of 24 hr urine samples and that of random urine samples (r=0.872).

Animals↗

PubMed2001

Novel structures in secreting the androgenic gland hormone.

The secretory granules in the androgenic gland of the terrestrial isopod Armadillidium vulgare, which have been indistinct for long time because of vulnerable structures, were revealed by using the rapid-freezing and freeze-substitution method. The fine structure of the androgenic gland is conspicuous by the distribution of numerous particular organelles in the cytoplasm consisting of the endoplasmic reticulum and the Golgi complex, and by having a number of highly organized structures developed between the androgenic gland cells. The structures connect to the intercellular space, which is seen as intercellular canaliculi for exporting the androgenic gland hormone. The plasma membranes near the particular structure of the intercellular canaliculi in the androgenic gland are often specialized to form cellular junctions. The secretory granules including the electron-dense materials, which are supposed to be peptides of androgenic gland hormone, are distributed beside the particular structure of the intercellular canaliculi. Some of the granules are seen to fuse with the plasma membranes. This observation suggests that, in the Armadillidium vulgare, the secretory granules containing androgenic gland hormone are transferred to the extracellular space through the intercellular canaliculi particularly developed for exporting the peptide hormone. This is the first evidence to show the secretory mechanism of the androgenic gland hormone in the Isopoda.

Animals↗

PubMed2001

Bronchiolitis obliterans with organizing pneumonia versus chronic eosinophilic pneumonia: high-resolution CT findings in 81 patients.

OBJECTIVE: The objective of this research was to compare high-resolution CT findings of bronchiolitis obliterans with organizing pneumonia (BOOP) with those of chronic eosinophilic pneumonia (CEP) and to determine whether high-resolution CT can differentiate the two. MATERIALS AND METHODS: We retrospectively reviewed high-resolution CT scans of 38 patients with BOOP and 43 patients with CEP. Without knowledge of the diagnosis, two radiologists evaluated the frequency and distribution of high-resolution CT findings in both groups of patients and made a diagnosis using a three-point scale of confidence. RESULTS: Nodules, nonseptal linear or reticular opacities, and bronchial dilatation were significantly more common in BOOP than in CEP (31.6% vs. 4.7%, p < 0.005; 44.7% vs. 9.3%, p < 0.001; and 57.9% vs. 25.6%, p < 0.005, respectively). Septal line thickening was more frequent in CEP than in BOOP (72.1% vs. 39.5%, p < 0.005). Peribronchial distribution of consolidation was more frequent in BOOP than in CEP (28.9% vs. 9.3%, p < 0.05). A correct diagnosis was made in 69.7% of cases, and the diagnostician was confident in 21.7%. Interobserver agreement was good (kappa = 0.6). CONCLUSION: Although several of the high-resolution CT findings of BOOP and CEP are different, these diseases are differentiated with confidence in only a small percentage of cases.

Adult↗

PubMed2001

A multicenter prospective randomized controlled trial of the efficacy of mild hypothermia for severely head injured patients with low intracranial pressure. Mild Hypothermia Study Group in Japan.

OBJECT: The criteria for the use of mild hypothermia (34 degrees C) in severely head injured patients have not been standardized. A prospective randomized controlled trial was conducted to determine whether mild hypothermia is essential in the treatment of severely head injured patients with low intracranial pressure (ICP). METHODS: At 11 medical centers, 91 severely head injured patients with an admission Glasgow Coma Scale score of 8 or less in whom ICP could be maintained below 25 mm Hg by conventional therapies were divided randomly into two groups: the mild hypothermia group (HT group, 45 patients) and the normothermia group (NT group, 46 patients). Patients in the HT group were exposed to mild hypothermia (34 degrees C) for 48 hours, followed by rewarming at 1 degrees C per day for 3 days, whereas patients in the NT group were exposed to normothermia (37 degrees C) for 5 days. The two groups were similar with respect to prognostic factors, and there was no difference in clinical outcome at 3 months postinjury. During treatment, there was a significantly greater use of neuromuscular blocking agents in the HT group (p = 0.011). During the initial 2 weeks postinjury, the incidences of pneumonia, meningitis, leukocytopenia, thrombocytopenia, hypernatremia, hypokalemia, and hyperamylasemia were significantly higher in the HT than in the NT group (p < 0.05). CONCLUSIONS: Mild hypothermia should not be used for the treatment of severely head injured patients with low ICP because this therapy conveys no advantage over normothermia in such patients.

Adolescent↗

PubMed2001

[Clinical efficacy of leuprolide acetate and combined treatment with estramustine for advanced prostate cancer].

BACKGROUND/PURPOSE: Twenty-two institutes have organized Keio University Prostate Cancer Study Group to study clinical efficacy and safety of Leuprolide acetate (Leuplin) for the treatment of advanced prostate cancer (clinical stage D1 and D2). Cotreatment of Leuplin and Estramustine phosphate disodium (Estracyt) has been performed to investigate its clinical efficacy. MATERIALS AND METHODS: One hundred and two cases of advanced prostate cancer were treated either with Leuplin alone (group I), Leuplin and Estracyt (group II) or Estracyt alone (group III). After 12 weeks treatment, clinical effects against subjective symptoms (pain, voiding difficulty, performance status and body weight), serum testosterone level, tumor size and serum PSA level were examined to investigate short-term effect of each treatment. The treatment had been continued for 24 months and the treatment effects including progression free survival and overall survival were analyzed. RESULTS: Clinical efficacy after 12 weeks treatment were examined among 97 cases (group I; 35 cases, group II; 36 cases, group III; 26 cases). The background of those patients in each group was statistically equal. Treatment effects against subjective symptoms and serum testosterone level statistically revealed no significant difference among 3 groups. Treatment effects against primary tumor, bone metastatic lesion, lymphnode metastatic lesion and serum PSA level were investigated and anti-tumor effect was characterized by total efficacy rate (complete remission rate plus partial remission rate) of each treatment group. Treatment efficacy rates for each lesion and PSA demonstrated no statistical difference among 3 treatment groups. Total efficacy rate of group I, II and III were 88.2%, 84.0% and 78.3%, respectively, which statistically revealed no significant difference. Total efficacy rate of each group after completing 24 months treatment was; group I 80.0%, group II 55.6% and group III 83.3%, which statistically showed no significant difference among 3 treatment groups. The median day for progression free survival of group I, II and III were 661, 731 and 517, respectively. The overall survival rate of group I, II and III after completing 24 months treatment were 77.5%, 83.0% and 72.4%, respectively. Both progression free survival rates and overall survival rates revealed no significant difference among 3 groups. Side effects during 24 months treatment were seen in 8.6% of group I, 47.2% of group II and 26.9% of group III, and these occurrence rates were significantly different among the groups (p = 0.0013). CONCLUSION: Although number of the cases had not been able to continue the treatment for their side effects, the statistical characterization demonstrated that cotreatment of Leuplin and Estracyt had no greater treatment effect than monotreatment of each drug.

Aged↗

PubMed2001

[Renal cell carcinoma metastatic to the ovary: a case report].

A 47-year-old woman underwent left radical nephrectomy in 1995, and pathological diagnosis showed a primary renal cell carcinoma with clear cell subtype. Four years later on her routine checkup, abdominal computerized tomography revealed a 9-cm of predominantly solid and partially cystic tumor in the pelvic cavity. The patient was referred to Gynecologic Department and a total hysterectomy with bilateral salpingo-oophorectomy was subsequently performed under the diagnosis of a left ovarian tumor. A cut surface of the solid component of the tumor was macroscopically yellowish. Pathological examination revealed alveolar growth of tumor cells with abundant clear cytoplasm including fat components. In some areas of the tumor, there were patterns of tubular structures which were cystically dilated. The typical findings usually found in the primary ovarian clear cell adenocarcinoma were absent in the tumor, and the final pathological diagnosis was left ovarian metastasis of renal cell carcinoma. The ovarian metastasis of renal cell carcinoma is quite rare and to our knowledge only eleven cases were reported in the past 20 years. We report on a case and review the literature.

Carcinoma, Renal Cell↗

PubMed2001

[Ultra-slow infusion dynamic MRI using an infusion pump: a new method for the evaluation of drug distribution in arterial infusion chemotherapy].

Ultra slow infusion dynamic MR imaging using an infusion pump(IP-MRI) was performed in six patients with metastatic liver tumor or unresectable gastric cancer to evaluate ant-cancer drug distribution. We used un implanted port for the infusion of Gd-DTPA by infusion pump. On IP-MRI, the speed of Gd-DTPA infusion was very slow (0.01 ml/sec) , the same as drug infusion at chemotherapy. The contrast enhancement of tumors was extremely clear. Therefore, IP-MRI was considered feasible for the evaluation of drug distribution.

Adult↗

PubMed2001

[Minocycline for the treatment of bronchiolitis obliterans associated with rheumatoid arthritis].

We discribe a rare case of rheumatoid arthritis (RA) complicated with bronchiolitis obliterans that was successfully treated with minocycline. Sixty four-year old woman with a four-years history of RA was admitted to the hospital because of dyspnea on exertion and polyarthritis. Pulmonary function test revealed marked decrease in V25 (0.10 l/s: 6.9%) and MMFR (12.6%). High resolution CT of the lung showed scattered centri-lobular micronodules in both lung fields, mucoid impaction, and hyperinflation. These findings indicated the presence of bronchiolitis obliterans. After 3 months of the treatment with minocycline, the patient showed a significant improvement of both arthritis and pulmonary function. Chest CT findings also improved after 1 year. The present case suggests that minocycline is effective for the treatment of bronchiolitis obliterans seen in patients with RA.

Anti-Bacterial Agents↗

PubMed2001

[An elderly woman with breast cancer and multiple liver metastasis that responded well to combination therapy of fadrozole and tamoxifen].

Few reports suggest a clinical benefit from combination treatment of fadrozole and tamoxifen for advanced breast cancer in elderly patients. We report the case of an 82-year-old breast cancer patient with multiple liver metastasis. After mastectomy, combination treatment of fadrozole and tamoxifen was added. Two months after the start of this treatment, there was a remarkable reduction in the size of metastatic lesions that continued over 6 months. CT examination revealed the largest lesion was reduced from 8.0 cm to 5.0 cm in largest diameter. The other two lesions were reduced from 3.0 cm to 2.0 cm. The reduction rate was 36%, indicating PR in the Response Evaluation Criteria in Solid Tumors (RECIST). The tumor marker CEA was remarkably reduced from 318 to 85 (ng/ml), and CA15-3 was reduced from 430 to 150 (U/ml). Tumor marker reduction continued over the 6 months corresponding to CT findings. No adverse effect was experienced. This combination therapy was useful and safe against metastatic breast cancer in a patient over 80 years of age.

Administration, Oral↗

PubMed2000

Cisplatin (CDDP) sensitizes human osteosarcoma cell to Fas/CD95-mediated apoptosis by down-regulating FLIP-L expression.

The mechanisms of escape from Fas/CD95-mediated apoptosis induced by immunosurveillance(NK cells and T cells) in tumor cells are correlated to tumorigenicity. Human osteosarcoma cell MG-63 constitutively expressed cell surface Fas antigen but was resistant to apoptosis by Fas stimulation. However, suboptimal dose of cisplatin(CDDP) could sensitize MG-63 cells to Fas-mediated apoptosis without up-regulation of cell-surface Fas antigen. Western blotting analysis showed that MG-63 cells constitutively expressed FLICE inhibitory protein long form(FLIP-L), which was a novel anti-apoptotic protein and had a potency of tumorigenicity. CDDP down-regulated FLIP-L in a time-dependent manner in MG-63 cells but did not influence expression of other anti-apoptotic molecules such as XIAP, c-IAP-1, c-IAP-2, FADD or pro-caspase-8. Moreover, antisense oligonucleotide to FLIP-L confirmed that down-regulation of FLIP-L induced sensitization to Fas-mediated apoptosis. These findings suggest that FLIP-L contributes to resistance to Fas-mediated apoptosis in MG-63 cells, and sensitization to Fas-mediated apoptosis by CDDP can be a new application of immune therapy.

Antineoplastic Agents↗

PubMed2000

Crossed linguo-buccal reflex in post-stroke patients.

A pathological crossed orofacial reflex, called crossed linguo-buccal reflex in the present study, was observed in approximately 1/3 of post-stroke patients with central facial palsy. Stroking with pressure two or three times with a split wooden tongue-blade to the tongue or palate contralateral to the central facial palsy elicited a reflex movement consisting of retraction of the angle of mouth and medio-posterior withdrawal of the buccal mucosa on the paretic side. Seventy-seven patients with central hemifacial palsy caused by a unilateral cerebral lesion were examined clinically, electromyographically and by computed tomography (CT) and magnetic resonance imaging (MRI). In addition, three men with bilateral cerebral lesions and bilateral crossed linguo-buccal reflexes were electromyographically examined. Twenty-two patients with unilateral cerebral lesions had this reflex. It was found that this reflex was most frequently observed in patients with a capsulo-caudate lesion involving the head of the caudate nucleus, the anterior limb and genu of the internal capsule. The electromyogram of the reflex showed increased activity in the orbicularis oris, depressor anguli oris, risorius, zygomaticus major and buccinator muscles on the paretic side with a long latency (254-856 ms), and a prolonged after-discharge after the stimulation. Reciprocal inhibition was observed in patients with bilateral positive reflexes. These findings suggest that liberation of the polysynaptic brainstem reflex in the medulla oblongata and pons from the indirect corticobulbar inhibition may underlie the occurrence of the crossed linguo-buccal reflex in post-stroke patients.

Adult↗

PubMed2000

Enhanced expression of Fas-associated death domain-like IL-1-converting enzyme (FLICE)-inhibitory protein induces resistance to Fas-mediated apoptosis in activated mast cells.

Mast cells play a critical role in host immune responses and are implicated in the pathogenesis of allergic inflammation. Though mouse mast cell line MC/9 expresses cell surface Fas Ag and is sensitive to Fas-induced apoptosis, activated MC/9 cells are resistant to Fas-induced cell death by cross-linking of FcepsilonRI or FcgammaR. Fas-associated death domain-like IL-1-converting enzyme (FLICE)-inhibitory protein (FLIP), a caspase-8 inhibitor that lacks the cysteine domain, is one of the negative regulators of receptor-mediated apoptosis. In this report, we show that activation of mast cells by cross-linking of FcepsilonRI or FcgammaR can induce enhanced expression of FLIP and consequently a resistance to Fas-induced apoptosis, although the expression level of Fas Ag is not changed. Addition of antisense oligonucleotide for FLIP prevents resistance to Fas-induced apoptosis of activated mast cells, suggesting that endogenous FLIP inhibits Fas-mediated apoptosis in activated mast cells. Thus, the enhanced expression of FLIP in activated mast cells contributes to the resistance to Fas-induced apoptosis, which may result in the development and prolongation of allergic inflammation.

Animals↗

PubMed2000

Flagellin from an incompatible strain of Pseudomonas avenae induces a resistance response in cultured rice cells.

The host range of Pseudomonas avenae is wide among monocotyledonous plants, but individual strains can infect only one or a few host species. The resistance response of rice cells to pathogens has been previously shown to be induced by a rice-incompatible strain, N1141, but not by a rice-compatible strain, H8301. To clarify the molecular mechanism of the host specificity in P. avenae, a strain-specific antibody that was raised against N1141 cells and then absorbed with H8301 cells was prepared. When a cell extract of strain N1141 was separated by SDS-polyacrylamide gel electrophoresis and immunostained with the N1141 strain-specific antibody, only a flagellin protein was detected. Purified N1141 flagellin induced the hypersensitive cell death in cultured rice cells within 6 h of treatment, whereas the H8301 flagellin did not. The hypersensitive cell death could be blocked by pretreatment with anti-N1141 flagellin antibody. Furthermore, a flagellin-deficient N1141 strain lost not only the induction ability of hypersensitive cell death but also the expression ability of the EL2 gene, which is thought to be one of the defense-related genes. These results demonstrated that the resistance response in cultured rice cells is induced by the flagellin existing in the incompatible strain of P. avenae but not in the flagellin of the compatible strain.

Amino Acid Sequence↗

PubMed2000

PICK1 interacts with and regulates PKC phosphorylation of mGLUR7.

The G-protein-coupled metabotropic glutamate receptor subtype 7a (mGluR7a) is a member of group III metabotropic glutamate receptors that plays an important role as a presynaptic receptor in regulating transmitter release at glutamatergic synapses. Here we report that the protein interacting with C-kinase (PICK1) binds to the C terminus (ct) of mGluR7a. In the yeast two-hybrid system, the extreme ct of mGluR7a was shown to interact with the PSD-95/Discs large/ZO-1 (PDZ) domain of PICK1. Pull-down assays indicated that PICK1 was retained by a glutathione S-transferase fusion of ct-mGluR7a. Furthermore, recombinant and native PICK1/mGluR7a complexes were coimmunoprecipitated from COS-7 cells and rat brain tissue, respectively. Confocal microscopy showed that both PICK1 and mGluR7a displayed synaptic colocalization in cultured hippocampal neurons. PICK1 has previously been shown to bind protein kinase C alpha-subunit (PKCalpha), and mGluR7a is known to be phosphorylated by PKC. We show a relationship between these three proteins using recombinant PICK1, mGluR7, and PKCalpha, where they were co-immunoprecipitated as a complex from COS-7 cells. In addition, PICK1 caused a reduction in PKCalpha-evoked phosphorylation of mGluR7a in in vitro phosphorylation assays. These results suggest a role for PICK1 in modulating PKCalpha-evoked phosphorylation of mGluR7a.

Animals↗

PubMed2000

Primary structure of human hepatocellular carcinoma-associated aldehyde dehydrogenase.

Tumor-associated aldehyde dehydrogenase (T-ALDH) is strongly expressed in hepatocellular carcinoma (HCC) but undetectable in normal liver. In the present study, this enzyme from human HCC, HCC T-ALDH, was purified and the partial amino acid sequences (384 residues) determined by direct protein sequencing matched the amino acid sequence (453 residues) deduced from cloned HCC T-ALDH cDNAs with an open reading frame. The coding sequences of HCC T-ALDH cDNA, human stomach ALDH3A1 cDNA [Hsu et al., J. Biol. Chem. 267 (1992) 3030-3037] and human squamous cell carcinoma (SCC) T-ALDH cDNA (Schuuring et al., GenBank I.D. M74542) matched one another except for discrepancies at four positions, with consequent P12R, I27F and S134A substitutions. R and A were found in HCC and SCC T-ALDHs, whereas P and S were present in stomach ALDH3A1. To confirm that these discrepancies would have general occurrence, coding sequences of HCC T-ALDH cDNAs from six patients and stomach ALDH3A1 cDNAs from two individuals were examined and all were found to encode ALDH3A1 having R, I and A at protein positions 12, 27 and 134, respectively, indicating HCC T-ALDH to be variant ALDH3A1 which is common in human stomach tissues.

Aldehyde Dehydrogenase↗

PubMed2000

Function of the N-terminal propeptide of an aminopeptidase from Vibrio proteolyticus.

An aminopeptidase from Vibrio proteolyticus was translated as a preproprotein consisting of four domains: a signal peptide, an N-terminal propeptide, a mature region and a C-terminal propeptide. Protein expression and analysis of the activity results demonstrated that the N-terminal propeptide was essential to the formation of the active enzyme in Escherichia coli. Urea dissolution of inclusion bodies and dialysis indicated that the N-terminal propeptide could facilitate the correct folding of the enzyme in vitro. Using L-Leu-p-nitroanilide as the substrate, the kinetic parameters (k(cat) and K(m)) of the pro-aminopeptidase and processed aminopeptidases were analysed. The results suggested that the N-terminal propeptide inhibited enzyme activity of the mature region. In contrast, the C-terminal propeptide did not show evidence of forming an active enzyme, of correctly folding in vitro or of inhibiting the active region.

Aminopeptidases↗

PubMed2000

Effects of physostigmine and calcium on acetylcholine efflux from the hippocampus of freely moving rats as determined by in vivo microdialysis and a radioimmunoassay.

The effects varying the concentration of Ca2+ in perfused artificial cerebrospinal fluid ([Ca2+]csf) on basal acetylcholine (ACh) efflux from the hippocampus of freely moving rats, in the presence and absence of the cholinesterase (ChE) inhibitor physostigmine, were investigated using in vivo microdialysis and a highly specific radioimmunoassay for ACh. In the absence of physostigmine, basal ACh efflux was 3.4+/-0.7 pg/30 min (mean +/- SEM) at [Ca2+]csf = 1.26 mM. Stepwise increases in [Ca2+]csf elicited a gradual increase in ACh efflux that was significant at [Ca2+]csf = 5.04 mM. Inhibition of ChE by addition of 10 microM physostigmine to the perfusate increased the efflux of ACh to 103.2+/-21.1 pg/30 min ([Ca2+]csf = 1.26 mM), and the efflux was augmented still further by increasing [Ca2+]csf, a change that became significant at [Ca2+]csf = 3.78. These results illustrate the sensitivity of basal ACh efflux from the hippocampus to changes in the extracellular Ca2+ concentration, and suggest that a more accurate picture of hippocampal cholinergic activity is obtained by microdialysis using normal artificial cerebrospinal fluid, under physiological conditions, rather than in the presence of a ChE inhibitor.

Acetylcholine↗