Biomedical subjects

H Fukuda

Publications and source records attributed to H Fukuda.

At least 235 records · Page 13Linked to original sources

PubMed1999

Cell-retained isoforms of vascular endothelial growth factor (VEGF) are correlated with poor prognosis in osteosarcoma.

Vascular endothelial growth factor (VEGF) is a major angiogenic factor. Osteosarcoma is characterised by hypervascularity and metastatic potential. We examined VEGF mRNA expression, VEGF isoform pattern and VEGF receptor (flt-1 and KDR) by RT-PCR analysis in 30 osteosarcomas. All 30 osteosarcomas expressed VEGF mRNA. 17 osteosarcomas (57%) expressed flt-1 mRNA, whilst 20 (67%) expressed KDR mRNA. 6/30 (20%) osteosarcomas were positive for VEGF121 only, 8 (27%) for VEGF121 + VEGF165, and 16 (53%) for VEGF121 + VEGF165 + VEGF189. Patients with osteosarcomas with VEGF165 (n = 24) had significantly poorer prognosis in comparison with those without VEGF165 (P = 0.022, Wilcoxon's test). The osteosarcomas with VEGF165 had significantly increased vascularity assessed on sections immunostained for CD34 (P < 0.001, Mann-Whitney U test). Although VEGF165 is a soluble isoform, it is also retained on the cellular surface. These results suggest that cell-retained VEGF isoforms (VEGF165, VEGF189) might be essential for neovascularisation in osteosarcoma, whilst the soluble VEGF121 isoform is not sufficient to stimulate neovascularisation in this type of neoplasm.

Adult↗

PubMed1999

Solid-phase synthesis, mass spectrometric analysis of the zinc-folding, and phorbol ester-binding studies of the 116-mer peptide containing the tandem cysteine-rich C1 domains of protein kinase C gamma.

Tumor-promoting phorbol esters activate protein kinase C (PKC) isozymes by binding to the zinc-finger like cysteine-rich domains in the N-terminal regulatory region. Our recent studies have revealed that only PKCgamma has two high affinity phorbol ester-binding domains, providing a structural blueprint for the rational design of PKCgamma-selective modulators for the treatment of neuropathic pain. To extend this approach, the 116-mer peptide containing the double cysteine-rich motifs of PKCgamma (gamma-C1A-C1B) has been synthesized for the first time using an Fmoc-solid phase strategy with a stepwise chain elongation. This peptide was purified by the reversed phase HPLC to give satisfactory mass data (MALDI-TOF-MS and ESI-TOF-MS). The peptide was successfully folded by zinc treatment and the folded peptide was analyzed intact under neutral conditions by ESI-TOF-MS. The multiple charge mass envelopes shifted to those of the lower mass charge state by addition of 4 molar equiv. ZnCl2, suggesting that gamma-C1A-C1B preserves some higher order structure by the zinc folding. Moreover, the mass spectrum of the zinc-folded peptide in the presence of EDTA clearly showed that gamma-C1A-C1B coordinates exactly four atoms of zinc. This zinc stoichiometry is identical to that of native PKCgamma. Scatchard analysis of the zinc-folded peptide revealed two binding sites of distinctly different affinities (Kd=6.0 +/- 1.5 and 47.0 +/- 6.6 nM) comparable to those reported by Quest and Bell for the GST fusion protein of gamma-C1A-C1B prepared by DNA recombination. These results indicate that gamma-C1A-C1B serves as an effective surrogate for native PKCgamma for the study of the structural characteristics of the binding recognition event and the design, discovery, and development of new PKCgamma-selective modulators.

Amino Acid Sequence↗

PubMed1999

Effects of phospholipids on growth of Chinese hamster ovary cells in serum-free media.

The effects of phosphatidic acid (PA) and lysophosphatidic acid (LPA) dispersed in serum-free media on the growth of Chinese hamster ovary (CHO) cells were investigated. After cells were incubated in serum-free media supplemented with PA or LPA for 3 d, the cellular growth was evaluated by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Supplementing PA from egg yolk lecithin to basal synthetic media such as alpha-MEM (minimum essential medium, alpha modification) markedly promoted the growth of CHO cells. PA from egg yolk lecithin also enhanced the cell growth in a serum-free medium containing insulin and transferring. When PA analogues with different acyl chains of C14-18 were compared, PA with unsaturated acyl chains, dioleoyl-PA (C18: 1), was most effective for stimulating the growth of CHO cells. Similar results were obtained when LPA was examined. These results suggest that PA and LPA, especially those with unsaturated acyl chains, are promising growth-promoting supplements for use as constituents in a low-protein serum-free medium.

Journal Article↗

PubMed1999

Biodiesel fuel production from plant oil catalyzed by Rhizopus oryzae lipase in a water-containing system without an organic solvent.

A new enzymatic method of synthesizing methyl esters from plant oil and methanol in a solvent-free reaction system was developed. It is anticipated that such plant oil methyl esters can be used as a biodiesel fuel in the future. Lipase from Rhizopus oryzae efficiently catalyzed the methanolysis of soybean oil in the presence of 4-30 wt% water in the starting materials; however the lipase was nearly inactive in the absence of water. The methyl ester (ME) content in the reaction mixture reached 80-90 wt% by stepwise additions of methanol to the reaction mixture. The kinetics of the reaction appears to be in accordance with the successive reaction mechanism. That is, the oil is first hydrolyzed to free fatty acids and partial glycerides, and the fatty acids produced are then esterified with methanol. Although R. oryzae lipase is considered to exhibit 1(3)-regiospecificity, a certain amount of 1,3-diglyceride was obtained during the methanolysis and hydrolysis of soybean oil by R. oryzae lipase solution. Therefore, the high ME content in the reaction mixture is probably attributable to the acyl migration from the sn-2 position to the sn-1 or sn-3 position in partial glycerides.

Journal Article↗

PubMed1999

Purification and characterization of lipase from Rhizopus chinensis cells.

Lipase from Rhizopus chinensis cells was purified and characterized. The molecular mass of purified lipase was 28.4 kDa and the optimal temperature and pH for its activity were 37 degrees C and 5.5, respectively. Purified lipase exhibited high hydrolytic activity against fatty acid methyl esters such as methyl caprylate, methyl laurate, and methyl palmitate. Freeze-dried lipase catalyzed the transesterification between olive oil and methyl laurate in n-hexane.

Journal Article↗

PubMed1999

Optimal production of recombinant protein by the baculovirus-insect cell system in shake-flask culture with medium replacement.

Sf9 insect cells infected with a recombinant baculovirus expressing beta-galactosidase and suspended in fresh medium (TNM-FH supplemented with 10% fetal bovine serum) at the time of infection were cultured in shake flasks at various combinations of initial cell density and multiplicity of infection (MOI). The effects of cell density and MOI on beta-galactosidase production were quantitatively analyzed by plotting the beta-galactosidase yield against the time integral of the viable cell density from the time of infection to the time when the beta-galactosidase production reached a plateau. The beta-galactosidase yield had a maximum value at a viable cell density time integral of approximately 8 x 10(6) cells.d/cm3 for each MOI used in a range from 0.01 to 10 plaque-forming units per cell (pfu/cell). Since glucose and fructose were exhausted when the culture reached 8 x 10(6) cells.d/cm3, it was concluded that protein production in a high-cell-density culture was limited by nutrient depletion in the culture medium, and hence the nutritional capacity of the medium was able to be determined as the viable cell density time integral at which the maximum product yield was attained. In cultures infected at a low MOI (< or =1 pfu/cell), the specific productivity, and thereby the yield, of beta-galactosidase declined with decreasing MOI due to the reduction in the proportion of initially infected cells. These results indicate that production of a recombinant protein in a culture with medium replacement at the time of infection can be optimized if the cells are infected at a high MOI (> or = 1 pfu/cell) and at a cell density such that the viable cell density time integral reaches the nutritional capacity just as the protein production is completed.

Journal Article↗

PubMed1999

Tissue distribution and kinetics of endogenous porphyrins synthesized after topical application of ALA in different vehicles.

The use of 5-aminolaevulinic acid (ALA) is gaining increasing attention for photosensitization in photodynamic therapy of superficially localized tumours. The aim of this work was to determine the kinetics of porphyrin generation in tissues after topical application of ALA delivered in different vehicles on the skin overlying the tumour and normal skin of mice. Maximal accumulation was found in tumour 3 h after ALA application in both cream and lotion preparations. Normal and overlying tumour skin tissues showed different kinetic patterns, reflecting histological changes when the latter is invaded by tumour cells. Liver, kidney, spleen and blood porphyrins also raised from basal levels, showing that ALA and/or ALA-induced porphyrins reach all tissues after topical application. During the first 24 h of ALA topical application, precursors and porphyrins are excreted by both urine and faeces. ALA lotion applied on the skin overlying the tumour induced higher accumulation of tumoural porphyrins than cream, and lotion applied on normal skin appeared to be the most efficient upon inducing total body porphyrins. This work has demonstrated the great influence of the formulation of ALA vehicle on penetration through the skin. Knowledge of the kinetics of porphyrin generation after different conditions of ALA application is needed for the optimization of diagnosis and phototherapy in human tumours.

Adenocarcinoma↗

PubMed1999

Factors influencing survival of patients undergoing hepatectomy for colorectal metastases.

BACKGROUND: The extent of surgical margin is still a matter of controversy with regard to outcome after liver resection for metastatic disease. The aim of this study was to clarify the significant prognostic factors after hepatectomy for colorectal metastases, with special reference to the surgical margin. METHODS: Ninety-six patients who underwent initial hepatic resection for liver metastases from colorectal cancer between 1992 and 1994 were studied. RESULTS: Overall 1-, 3- and 5-year survival rates were 94, 61 and 51 per cent respectively. All of the independent factors associated with poor prognosis after hepatic resection were tumour-related factors, such as the number of tumours (four or more), presence of portal vein invasion, hepatic vein invasion and absence of a fibrous pseudocapsule. A positive resection margin was not an independent prognostic factor, because of its strong relationship with the number of tumours resected. CONCLUSION: A generous surgical margin is not essential for curative hepatic resection, although positive surgical margins should be avoided. New potential risk factors which affect survival, such as the presence of portal vein or hepatic vein invasion and the absence of a pseudocapsule, may be helpful for defining the indications for postoperative adjuvant treatment.

Adult↗

PubMed1999

Transcriptional regulation of fatty acid synthase gene by insulin/glucose, polyunsaturated fatty acid and leptin in hepatocytes and adipocytes in normal and genetically obese rats.

Transcriptional regulation of the fatty acid synthase (FAS) gene by insulin/glucose, polyunsaturated fatty acids and leptin was investigated in hepatocytes and adipocytes of Wistar fatty rats and their lean littermates. The sequence spanning nucleotides -57 to -35 of FAS gene, which is responsive to insulin/glucose stimulation [Fukuda, H., Iritani, N. & Noguchi, T. (1997) FEBS Lett. 406, 243-248], was linked to a reporter gene containing a heterologous promoter and transfected into rat hepatocytes or adipocytes. The activity of the reporter, chloramphenicol acetyltransferase, in the presence of glucose alone was similar in the primary cultured cells from the lean and obese rats. In the presence of insulin/glucose, however, chloramphenicol acetyltransferase activity was markedly increased in hepatocytes of lean rats, but was not significantly increased in those of obese rats. The stimulation by insulin/glucose was reduced in arachidonic acid-treated cells of lean rats. Similarly, the stimulation by insulin/glucose was reduced in leptin-treated cells and in cells from lean rats containing an expression vector encoding leptin. However, neither polyunsaturated fatty acids nor leptin-treated cells from obese rats responded to insulin-stimulation. The same effects were observed at endogenous FAS mRNA and enzyme levels. Similar results were seen in adipocytes, although the stimulation and suppression were much smaller than in hepatocytes. The insulin-binding capacities of the receptors of liver and adipose tissue were reduced in the presence of leptin or polyunsaturated fatty acids. Leptin and polyunsaturated fatty acids appeared to suppress the insulin stimulation of FAS transcription by reducing the insulin-binding capacities of receptors. Leptin converged on the insulin/glucose response element of FAS gene and suppressed the transcription.

Adipocytes↗

PubMed1999

Haemodynamic changes in non-alcoholic (viral) liver cirrhosis studied by computed tomography (CT) arterial portography and CT arteriography.

AIMS: To evaluate haemodynamic and vascular changes in non-alcoholic (viral) cirrhosis on conventional computed tomography (CT), CT arteriography (CTA) and CT arterial portography (CTAP), and to determine the cause of the observed reticular stain on angiography. METHODS: Using surgically resected liver specimens from 31 patients with viral hepatitis associated hepatocellular carcinoma, images of conventional CT, CTA, CTAP and the sinusoidal phase of hepatic arteriography were retrospectively analysed and compared with pathology of the non-cancerous portion of the liver. RESULTS: Computed tomography arteriography showed inhomogeneous enhancement (diffuse, low-density nodules) in a total of 16 samples (52%); in eight of 10 (80%) cirrhotic livers, three of six (50%) precirrhotic livers, five of 12 (42%) livers with chronic active hepatitis and none of three with no active liver disease. The frequency of inhomogeneous enhancement became significantly higher with increasing severity of parenchymal damage (P < 0.05). In contrast, conventional CT and CTAP showed homogeneous enhancement in all 31 (100%) patients. There was no correlation between inhomogeneous enhancement on CTA and reticular staining on sinusoidal-phase hepatic angiograms. Inhomogeneous enhancement was frequently seen in patients with hepatitis B surface antigen and/or anti-hepatitis C virus antibody compared with those without them (P < 0.05). CONCLUSION: The CTA was much more sensitive in detecting haemodynamic changes in the cirrhotic liver than CTAP, conventional CT and sinusoidal-phased hepatic angiography. Further study is required to clarify the mechanism of inhomogeneous enhancement on CTA and homogeneous enhancement on CTAP seen in cirrhosis.

Adult↗

PubMed1999

Parenchymal echo patterns of cirrhotic liver analysed with a neural network for risk of hepatocellular carcinoma.

BACKGROUND: To objectively evaluate the parenchymal echo patterns of the liver in cirrhosis, an image analysing system in which a neural network is used has been found capable of numerically calculating coarse score (CS). Using this system, we analysed whether or not CS can serve as a predictive factor for the development of hepatocellular carcinoma (HCC). METHODS: The risk factors for HCC were evaluated in 95 patients with liver cirrhosis with an average follow-up period of 2041 +/- 823 days. We used a three-layer feed-forward neural network and a back-propagation algorithm to calculate CS. RESULTS: There were strong correlations between CS, alanine aminotransferase (ALT) and alpha-fetoprotein (AFP) and the average cumulative incidence rate of HCC evaluated by the Cox's proportional hazards model. The adjusted rate ratios were estimated to be 3.00, 2.80 and 2.01, respectively. The cumulative risks of HCC were significantly higher with an initial CS > or = 1.5 than with an initial CS < 1.5, with ALT > or = 80 IU/L than with initial ALT < 80 IU/L and with AFP > or = 20 ng/mL than with initial AFP < 20 ng/mL, all analysed by the log-rank test. CONCLUSIONS: Coarse score is a useful predictor for development of HCC.

Adult↗

PubMed1999

Treatment of obstructive sleep apnea syndrome with a Kampo-formula, San'o-shashin-to: a case report.

The following describes a 76-year-old male with obstructive sleep apnea syndrome successfully treated with a Kampo-formula, San'o-shashin-to (Formula medicamentorum tres ad dispellendi cordis). Polysomnography, performed before and after administration of San'o-shashin-to, revealed that the apnea index decreased from 11.1 events/hour to 4.1 events/hour, and that the apnea plus hypopnea index decreased from 18.4 events/hour to 10.7 events/hour. The patient was normo-weight (body mass index: 20.4 kg/m2), and events of sleep apnea and hypopnea were mostly noted during a non-rapid eye movement sleep. It is possible that San'o-shashin-to has some alleviating effects on the upper airway resistance during sleep.

Aged↗

PubMed1999

Nurses' workload associated with 16-h night shifts on the 2-shift system. I: Comparison with the 3-shift system.

To assess nurses' workload with 16-h night shifts on a 2-shift system, we investigated the differences between workloads with each shift on the 2- and 3-shift systems with questionnaires on subjective symptoms and measuring heart rate and physical activity. It was found that the 2-shift nurses during the 16-h night shifts complained of fatigue less frequently and showed general decreases in heart rate and physical activity compared with the 3-shift nurses during 8-h evening and night shifts. The results suggest that a 2-h nap, an increase of staff, and a day off may reduce the nurses' workload when they have 16-h night shifts.

Adult↗

PubMed1999

Nurses' workload associated with 16-h night shifts. II: Effects of a nap taken during the shifts.

This study aimed at examining the effects on the subjective symptoms in nurses of both timing and length of a 2-h nap during a 16-h night shift. Compared to pre-nap levels, sleepiness, fatigue, and dullness increased immediately after napping. Afterwards, sleepiness decreased significantly, and the other symptoms returned to the pre-nap values. The nurses' subjective symptoms after napping were not associated with the timing of the nap and post-nap fatigue lasted longer as the nap time increased (> 1.5 h). These results suggest that for effective napping during long night shifts, the nap length should be determined carefully to avoid persistent sleep inertia.

Adult↗

PubMed1999

Gastric ulcer formation after the Hanshin-Awaji earthquake: a case study of Helicobacter pylori infection and stress-induced gastric ulcers.

BACKGROUND: Both Helicobacter pylori (H. pylori) infection and various stresses are known to induce peptic ulcer disease of the upper gastrointestinal tract. However, the pathogenetic relationship between the two factors has not yet been clarified. We conducted a case-control study to examine whether H. pylori infection played a role in the development of gastric ulcer (GU) induced by life-event stresses that were experienced after the Hanshin-Awaji earthquake. MATERIALS AND METHODS: Serum samples from patients in the devastated area who developed GUs during the 2 months following the Hanshin-Awaji earthquake and those from GU patients in the same area during the corresponding period of the previous year, and from gender-, age- and institute-matched ulcer-free controls were tested for the presence of the H. pylori IgG antibody. RESULTS: A significant association between H. pylori infection and the development of GU in uninjured patients was observed in all sets [matched odds ratio (OR) = 3.23, 95% confidence interval: 1.95-5.35]. Moreover, the prevalence of H. pylori infection in patients who developed GUs after the earthquake was not different from that for GU patients in the previous year. In contrast, there was no association between H. pylori infection and the development of GU in the physically injured patients after the earthquake. CONCLUSIONS: H. pylori infection may play an important role in the development of GUs that are induced by emotional life-event stresses.

Antibodies, Bacterial↗

PubMed1999

Mortality in relation to urinary and faecal incontinence in elderly people living at home.

OBJECTIVE: To examine the relationship between incontinence and mortality in elderly people living at home. DESIGN: Of the randomly selected people aged 65 years and older living in Settsu city, Osaka in October 1992, 1405 were contacted and constituted the study cohort. Follow-up for 42 months was completed for 1318 (93.8%; 1129 alive, 189 dead). MEASURES: Data on general health status, history of health management, psychosocial conditions and urinary and faecal incontinence were collected by interview during home visits at the time of enrolment. RESULTS: From the Kaplan-Meier analysis, the estimated survival rates decreased with a decline in continence in both the 65-74 and 75 years and older age groups. From the Cox proportional hazards model, unadjusted hazard ratios of minor, moderate and severe incontinence for mortality, compared with continence, were 2.27, 2.96 and 5.94, respectively. Multivariate analysis yielded adjusted hazard ratios of minor, moderate and severe incontinence of 0.99, 1.17 and 1.91, respectively, leaving severe incontinence as the significant factor, when other indicators are controlled. CONCLUSIONS: Incontinence is related to mortality and severe incontinence represents an increased risk factor for mortality in elderly people living at home.

Activities of Daily Living↗

PubMed1999

The human amygdala plays an important role in gaze monitoring. A PET study.

Social contact often initially depends on ascertaining the direction of the other person's gaze. We determined the brain areas involved in gaze monitoring by a functional neuroimaging study. Discrimination between the direction of gaze significantly activated a region in the left amygdala during eye-contact and no eye-contact tasks to the same extent. However, a region in the right amygdala was specifically activated only during the eye-contact task. Results confirm that the left amygdala plays a general role in the interpretation of eye gaze direction, and that the activity of the right amygdala of the subject increases when another individual's gaze is directed towards him. This suggests that the human amygdala plays a role in reading social signals from the face.

Adult↗

PubMed1999

Alternating combination chemotherapy COP (cyclophosphamide, vincristine, prednisone) and MP (melphalan, prednisone) in multiple myeloma: a multicenter phase II study (JCOG8906). Lymphoma Study Group of the Japan Clinical Oncology Group.

BACKGROUND: The main form of cytotoxic treatment for multiple myeloma (MM) is conventional dose chemotherapy at present. METHOD: Between November 1989 and December 1991, a multicenter phase II study of alternating conventional dose combination chemotherapy (CCT) with COP (cyclophosphamide, vincristine, prednisone) and MP (melphalan and prednisone) to evaluate its clinical usefulness for overt MM patients was conducted by the Lymphoma Study Group of the Japan Clinical Oncology Group (JCOG). RESULTS: Eighty-one previously untreated patients were enrolled in the study. For 69 eligible patients, the response rate was 50.7% [95% confidence interval (CI) 38.4-63.0%]. The median survival time was 38.5 (95% CI 32.0-44.4) months. The survival rate at 3 and 5 years was 50.7 and 27.3%, respectively. Grade 4 toxicity by the criteria of the World Health Organization consisted of anemia in eight patients, leucocytopenia in three, cardiac in one and hepatic in two, but there was no treatment-related death. CONCLUSION: The COP-MP regimen for overt MM is thought to be one of the effective CCTs according to the results of the present phase II study.

Adult↗