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Biomedical subjects

S Fukushima

Publications and source records attributed to S Fukushima.

At least 127 records · Page 7Linked to original sources

Material analysis end-station of the Hyogo-ken beamline at SPring-8.

Plans to construct surface-analysis equipment which will be placed on beamline BL24XU of SPring-8 are presented. There are three experimental hutches in BL24XU, which are available simultaneously by using diamond monochromators as beam splitters. The purpose of the surface-analysis equipment is the simultaneous measurement of fluorescent and diffracted X-rays in grazing-incidence geometry. The instrument is equipped with a solid-state detector (SSD) and a flat position-sensitive proportional counter (PSPC) combined with analysing crystals for X-ray fluorescence (XRF) analysis. A curved PSPC and the goniometer that mounts the SSD used for XRF are also installed for X-ray diffraction. X-ray fluorescence holography and polarized X-ray emission spectroscopy modes are available, so three-dimensional images of atomic configurations and also the anisotropic structure of materials will be studied.

Journal Article↗

Epithelial cell proliferation in the digestive tract induced by space restriction and water-immersion stress.

The effects of space restriction and water-immersion stress on epithelial cell proliferation in the digestive tract, with special attention to the esophagus, stomach and duodenum, in 8-week-old SD male rats were examined. Histological assessment revealed spotted hemorrhagic lesions in the fundus of the glandular stomach, accompanied by statistically increased 5-bromo-2'-deoxyuridine (BrdU) labeling index in the fundic and pyloric regions. Furthermore, biochemical analysis demonstrated an increased activity of ornithine decarboxylase (ODC) and spermidine/spermine N1-acetyltransferase (SAT), known as key late-limiting enzymes of the polyamine pathway, in the gastric fundus. The stress may induce a remarkable increase in expression of c-fos, c-jun and c-myc mRNAs in both fundic and pyloric regions of the glandular stomach. There were no remarkable changes in the esophagus. These results indicate that space restriction and water-immersion stress induced cell proliferation in the glandular stomach through overexpression of proto-oncogenes and increased ODC and SAT activities that might be related to the promotion of gastric carcinogenesis.

Acetyltransferases↗

Modification by 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP) of 3,2'-dimethyl-4-aminobiphenyl (DMAB)-induced rat pancreatic and intestinal tumorigenesis.

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) has been shown to induce marked atrophic changes of exocrine pancreas of rats when given at 400 ppm in diet. On the other hand, 3,2'-dimethyl-4-aminobiphenyl (DMAB) causes pancreatic acinar tumors. Both chemicals also induce intestinal tumors. In the present experiment, the possible promotional effects of PhIP on DMAB-induced carcinogenesis in the rat were investigated with particular attention given to the pancreas and intestine. After initiation with subcutaneous injections of DMAB (150 mg/kg b.w.) once a week for 3 weeks, PhIP was administered in the diet at doses of 200, 100, 25 and 0 ppm from weeks 5 to 40. In a dose-dependent manner, PhIP clearly increased the numbers of basophilic acinar foci and nodules while decreasing development of acidophilic lesions. The incidences of adenocarcinomas of the small intestine but not the colon demonstrated a tendency for an increase with the higher doses of PhIP. The results thus indicated that PhIP administration after DMAB treatment exerts two different effects on pancreatic acinar cell lesions, enhancing the growth of basophilic foci and suppressing that of their acidophilic counterparts. Any influence on alimentary canal tumorigenesis was limited to the small intestine.

Adenocarcinoma↗

Infrequent involvement of microsatellite instability in urinary bladder carcinomas of the NON/Shi mouse treated with N-butyl-N-(4-hydroxybutyl)nitrosamine.

Variation in the frequency of microsatellite instability (MSI) has been reported in different kinds of human malignant tumors, with less than one-third of invasive urinary bladder carcinoma cases estimated to be affected. Here we investigated the MSI for 27 microsatellite sequences in invasive urinary bladder carcinomas of the NON/Shi mouse induced by N-butyl-N-(4-hydroxybutyl)nitrosamine. A total of 28 urinary bladder carcinomas of both transitional cell and squamous cell types were studied. All were invasive (greater than pT3) and high-grade and 10 of them had metastasis. Only two (11%) of 18 primary bladder carcinomas without metastasis foci showed alterations in one or two loci. None of 10 pairs of urinary bladder carcinomas and metastasis foci demonstrated any alterations. In conclusion, MSI which represents a defect in the DNA mismatch repair system is infrequent and therefore unlikely to be a critical step in genesis of invasive mouse urinary bladder carcinomas.

Animals↗

Characterization of physical entrapment and chemical conjugation of adriamycin in polymeric micelles and their design for in vivo delivery to a solid tumor.

An anticancer drug adriamycin (ADR) was incorporated into polymeric micelles forming from poly(ethylene glycol)-poly(aspartic acid) block copolymer by chemical conjugation and physical entrapment. Structural stability of the polymeric micelles was found to be dependent on both the contents of chemically conjugated and physically entrapped ADR. The polymeric micelle with high contents of the chemically conjugated ADR and the physically entrapped ADR expressed very high in vivo antitumor activity against murine C 26 tumor, while the polymeric micelle with only the chemically conjugated ADR showed negligible in vivo activity. This indicates that the physically entrapped ADR played a major role in antitumor activity in vivo. For the polymeric micelle with the high ADR contents, it was found that a dimer of adriamycin molecules formed and that this dimer was physically entrapped in the inner core of the micelle as well as intact ADR.

Animals↗

F344/Shi rats bearing type b catalase-1 locus are sensitive to sodium L-ascorbate promotion of two-stage urinary bladder carcinogenesis.

Our previous data showed that F344/DuCrj and LEW/Crj rat strains bearing the type a catalase-1 locus (CS1a) are sensitive to the promoting activity of sodium L-ascorbate (Na-AsA) in 2-stage urinary bladder carcinogenesis, whereas ODS/Shi and WS/ Shi rat strains bearing the type b catalase-1 locus (CS1b) are resistant. In present study, we investigated the susceptibility of F344/Shi rats also bearing the CS1 to the Na-AsA-promoting effects on bladder tumor development. Male rats, 6 weeks old, were given 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in their drinking water for 4 weeks, then fed either basal diet supplemented with 5% Na-AsA or no chemicals for 32 weeks. The rats given BBN alone had a few small carcinomas in the urinary bladder. In contrast, animals administered BBN-Na-AsA had many large carcinomas. Administration of Na-AsA was associated with significant elevation of urinary pH and L-ascorbic acid. The results indicate that F344/Shi rats are sensitive to the promoting effects of Na-AsA on 2-stage urinary bladder carcinogenesis, and thus that the CS1 locus may not influence susceptibility to promotion.

Alleles↗

Possible rare involvement of O6-methylguanine formation as a significant mutational factor in mouse urinary bladder carcinogenesis models.

O6-methylguanine is known as one of the major premutagenic lesions in the human and rodent carcinogenesis process. O6-methylguanine-DNA methyltransferase (MGMT), which repairs methylated guanine bases, might prevent the G:C to A:T transition, and transgenic mice carrying this MGMT gene have been reported to be less sensitive to the carcinogenicity of certain alkylating agents. Here we utilized MGMT transgenic mice to assess the significance of O6-methylguanine formation during urinary bladder carcinogenesis. In experiment 1, 100 and 60 ppm N-butyl-N(4-hydroxybutyl)nitrosamine was given for 20 weeks to transgenic and non-transgenic mice in their drinking water. The incidences of urinary bladder carcinomas were not different between transgenic mice and non-transgenic mice. The mutational spectrum of the p53 gene was evaluated by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. The pattern of p53 mutations of transgenic and non-transgenic mice did not differ, and the frequencies of mutations were 40% and 42%, respectively. G:C to A:T transition mutations were particularly infrequent (1 of 14 mutations, 7%). In experiment 2, N-methyl-N-nitrosourea, which might induce O6-methylguanine in affected alleles, was given once a week, 3 times (total 5 mg) by direct instillation into the urinary bladder through an abdominal incision. No significant neoplastic lesions were detected, although the experiment was limited by severe toxicity of the treatment. p53 immunostaining was done and there was no difference in transgenic and non-transgenic mice. These results suggest that O6-methylguanine formation might not be a significant mutational factor in these mouse urinary bladder carcinogenesis models.

Adenosine Deaminase↗

Host genes affecting survival period of chemically induced bladder cancer in mice.

Treatment of C57BL/6 J (B6) and NON male mice with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) resulted in a high incidence of bladder cancer. The mean survival period, however, differed significantly by strain: 481+/-219 days in B6 (n = 31) and 203+/-119 days in NON (n = 30) (P < 0.0001). Major causes of death were renal failure due to obstruction of the urinary tract, or local invasion of tumors. The fact that the BBN-treated NON x B6 reciprocal F1 mice had survival periods as short as those of the parental NON mice suggests a genetically dominant susceptibility in NON or recessive resistance in B6. A linkage analysis of 248 back-cross mice to B6 suggested at least two quantitative trait loci determining the length of the survival period: one was mapped close to D2Mit260 (logarithm of odds, LOD, score 2.21), a microsatellite marker locus 83 cM from the centromere on chromosome 2, and another was close to D6Mit159, 7 cM from the centromere on chromosome 6 (LOD score 2.51).

Animals↗

Arthroscopic Bankart suture repair for traumatic anterior shoulder instability: analysis of the causes of a recurrence.

Eighty-two patients with traumatic anterior shoulder instability were treated with an arthroscopic transglenoid multiple suture technique (Caspari's method) and followed-up for more than 2 years. A retrospective analysis of the clinical outcome was performed to determine the factors related to poor results. The mean age at operation was 21 years (range, 13 to 50 years) and the mean follow-up period was 40 months (range, 24 to 70 months). According to the status of the ligament-labrum complex and the glenoid bone defect, the Bankart lesions were classified into five types arthroscopically. There were 21 shoulders of type 1, 33 shoulders of type 2, 22 shoulders of type 3, and 6 shoulders of type 5. Twenty-four of the patients played contact sports before the operation. The clinical outcome was assessed by Rowe's criteria (1978). To analyze the factors related to a poor outcome, a multivariate analysis was done to assess the influence of 12 clinical factors (age at operation, age at first dislocation, sex, dominant side, disease duration, number of dislocations, sporting activity before operation, inferior joint laxity, thickness of the ligament-labrum complex, type of Bankart lesion, number of sutures, and method of suture fixation). Fifty-five of 82 patients had an excellent outcome, 14 had a good result, and 13 had a poor result. According to postoperative instability, redislocation was seen in 13 patients (16%), resubluxation in 2 patients (2%), with a recurrence rate of 18%. The mean limitation of external rotation at 90 degrees abduction was 6.0 degrees (range, 0 degrees to 30 degrees), and there was a 10 degrees loss of external rotation in 10 patients. The factors significantly related to recurrence were a type 3 Bankart lesion, playing contact sports preoperatively, a thin ligament-labrum complex, and repair with less than four sutures. In conclusion, a 18% rate of recurrence is not acceptable. To obtain a better clinical outcome, very careful selection of patients for this technique is necessary. Our analysis of the factors related to a poor outcome may help to decide what the proper indications are for this technique.

Adolescent↗

Trichomonas foetus meningoencephalitis after allogeneic peripheral blood stem cell transplantation.

A 34-year-old man with refractory acute myelogenous leukemia underwent allogeneic peripheral blood stem cell transplantation (PBSCT) from his HLA-matched sibling. Engraftment was prompt and no acute GVHD developed. However, high fever persisted even after engraftment, and the patient developed headache, diplopia, vertigo and nuchal rigidity on day 20 posttransplant. Cerebrospinal fluid (CSF) showed pleocytosis with no detectable microorganisms. Despite therapy with broad-spectrum antibiotics, antifungal agents and antituberculous drugs, he developed rapid mental deterioration with seizures and died on day 40. Just prior to his death, trichomonads were isolated from both CSF and urine. Scanning electron microscopic examination identified the trichomonad as Trichomonas foetus. At autopsy, trichomonads were detected histopathologically in an area involving meningoencephalitis. To our knowledge, this is the first case of T. foetus meningoencephalitis in a recipient of allogeneic PBSCT and, more importantly, the first human case of T. foetus infection.

Adult↗

Clonal analysis of urothelial carcinomas in C3H/HeN<-->BALB/c chimeric mice treated with N-butyl-N-(4-hydroxybutyl)nitrosamine.

The histological background for multifocal and metachronous development of urothelial carcinomas remains equivocal, although accumulated genetic evidence suggests monoclonal origin of multiple urothelial carcinomas. Clonal development of various preneoplastic and neoplastic urothelial lesions of C3H<-->BALB/c chimeric mice induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was immunohistochemically investigated using a C3H strain-specific antibody. All tumor masses induced in the mice treated with 0.05% BBN for 20 weeks were composed of neoplastic cells of a single parental type, which is indicative of monoclonal lesions. Three of 10 animals harbored two or more separate carcinomas of different clonal type, which is indicative of multicentric development applicable in this model. Using DNAs derived from urothelial carcinomas and tumor-adjacent urothelium of chimeric mice, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing were performed for p53 gene exons 5-7. p53 mutations were identified in four of 11 (36%) dysplasias and non-invasive carcinomas (carcinoma in situ and pTa tumor) and 13 of 22 (59%) invasive carcinomas. Only in a single case were identical p53 mutations found in separate urinary bladder carcinomas. In contrast to the random distribution of urothelial proliferating units in chimeric mice without chemical supplement, invasive carcinomas in BBN-treated mice were accompanied by widely-distributed preneoplastic and neoplastic lesions of the same clonality, which occasionally had frequent foci of microinvasion. This is indicative of lateral clonal expansion of the clones, which precedes the bulk of invasive carcinomas. Thus, two aspects of 'field change' of the urothelium became evident in this model: either independent transformation events or lateral clonal expansion might, respectively, result in multicentric and monoclonal carcinoma development in the urinary tract.

Animals↗

Presence of a threshold for promoting effects of phenobarbital on diethylnitrosamine-induced hepatic foci in the rat.

The dose dependence of the hepatopromoting effects of phenobarbital (PB) was investigated in a rat liver medium-term bioassay (Ito test) to elucidate a practical threshold level. F344 rats were given a single i.p. injection of diethylnitrosamine (200 mg/kg body wt) and subjected to two-thirds partial hepatectomy at week 3. Commencing 2 weeks from the start, PB at doses of 0, 1, 2, 4, 7.5, 15 or 500 p.p.m. in experiment 1 and 0, 0.01, 0.1 or 0.5 p.p.m. in experiment 2 were fed to the rats for 6 weeks. Experiment 3 was conducted to confirm previous data using the same medium-term bioassay, with PB at doses of 0, 1, 2, 4, 7.5, 15, 30, 60, 125, 250 or 500 p.p.m. fed to the rats. All surviving animals were killed at week 8 in these experiments and their livers were immunohistochemically examined for expression of glutathione S-transferase placental form (GST-P). Quantitative values for GST-P-positive foci in the liver were increased dose dependently in rats given 60-500 p.p.m. PB. However, those for doses in the range 1-7.5 p.p.m. demonstrated a decrease as compared with the control group (0 p.p.m.), with significant differences observed for 1 and 2 p.p.m.. The results for 15-30 and 0.01-0.5 p.p.m. were comparable with the control values. Examination of transforming growth factor-alpha (TGF-alpha)-positive foci also produced similar results to those for GST-P in experiment 1. Immunohistochemical staining of TGF-alpha and GST-P using serial liver sections demonstrated that the TGF-alpha-positive foci comprised a sub-population of the GST-P-positive lesions, being approximately 1/8-1/10th as common in livers of animals treated with PB. TGF-alpha-positive foci were almost always negative on immunostaining for TGF-beta. Western blotting for proteins CYP2B1, 2C6 and 3A2 revealed a good correlation between changes in GST-P-positive foci and CYP3A2 protein expression. The finding of inhibition effects at low doses of PB confirms the presence of a threshold level for promoting effects by PB on liver carcinogenesis in rats.

Animals↗

Assessment of cell cycle-related elements p53, p21WAF1/Cip1, cyclin D1 and PCNA in a mixed transitional cell carcinoma and adenocarcinoma of the renal pelvis: a case report.

A case featuring a well differentiated adenocarcinoma mixed with a transitional cell carcinoma (TCC) arising in the renal pelvis of a 63-year-old woman is presented. Daughter tumors, located in the ureter and the uretero-vesical junction, were entirely TCC in character. Immunohistochemical assessment of cell cycle-related proteins revealed overexpression of cyclin D1 but reduced p21WAF1/Cip1 or PCNA expression in the adenocarcinomatous regions. Conversely, expression of p21WAF1/Cip1 and PCNA was high in the TCC components. Immunohistochemical staining for p53 was negative and PCR-SSCP analyses confirmed the absence of any mutation. Therefore, assessments on the altered expression of cell cycle-related elements may contribute to our understanding of tumor biology in adenocarcinomas and TCCs of the renal pelvis and to identifying the similarities and differences between the two different cell types.

Adenocarcinoma↗

Expression and localization of ornithine decarboxylase in reversible papillomatosis induced by uracil in rat bladder.

Direct mechanical irritation by uracil calculi formed following feeding of 3% uracil in the diet to male rats produces severe papillary hyperplasia (papillomatosis, which is reversible) of bladder epithelium. To evaluate the mechanism of the appearance of uracil-induced papillomatosis, we examined the changes of the enzyme activity and the localization of ornithine decarboxylase (ODC), as well as polyamine biosynthesis, and epithelial proliferation, that accompany the sequential bladder epithelial changes following administration and withdrawal of uracil. Moreover, expression of ODC mRNA was investigated using northern blotting and localization of ODC mRNA was demonstrated using in situ hybridization. ODC activity during uracil administration was maintained at a high level compared to that in normal epithelium, but sharply decreased after cessation of uracil treatment. The accumulation of ODC protein was observed in the proliferating bladder epithelium by immunohistochemical examination and western blotting analysis, and even after cessation of treatment, the protein binding to anti-ODC antibody remained mildly elevated. Sequential changes of proliferating cell nuclear antigen (PCNA)-positive cells in the epithelium during the development and disappearance of papillomatosis correlated with ODC activity. ODC mRNA was expressed strongly in the proliferating epithelium in rats treated with uracil and weakly in normal epithelium, in accordance with the location of ODC protein. Consequently, our data demonstrate that cell proliferation in the development of papillomatosis is closely associated with polyamine metabolism, and moreover suggest that ODC activity is up-regulated at a post-translational step.

Animals↗

N-methyl-N-nitrosourea concentration-dependent, rather than total intake-dependent, induction of adenocarcinomas in the glandular stomach of BALB/c mice.

The influence of the level of carcinogen exposure on histopathological types and cellular differentiation of the induced tumors was examined in 100 male BALB/c mice given N-methyl-N-nitrosourea (MNU) in their drinking water at 240 ppm on alternate weeks (total exposure: five weeks) (groups 1), at 120 ppm similarly (total exposure: ten weeks) (group 2), at 60 ppm for 20 weeks continuously (group 3), or at 30 ppm for 40 weeks continuously (group 4). Forty-three differentiated and 17 undifferentiated type adenocarcinomas were induced. Glandular stomach carcinomas and undifferentiated type lesions were more common in mice treated with a high concentration of MNU for a short period than with a low concentration of MNU for a long period, even though total measured intake of MNU was smaller (P < 0.01). All the induced glandular stomach carcinomas, independent of the treatment schedule, consisted entirely of gastric phenotype cells. In conclusion, the induction of glandular stomach cancers and the proportion of undifferentiated type lesion depend not on the total quantity, but rather on the concentration of the carcinogen, while the phenotypic expression of tumor cells in not affected by the differences in the administration protocol.

Adenocarcinoma↗

Clinical significance of interruption of therapy with allylestrenol in patients with benign prostatic hypertrophy.

BACKGROUND: A multicenter, clinical trial investigated the effects of an interruption of antiandrogen therapy on subjective and objective clinical parameters in patients with benign prostatic hypertrophy (BPH). METHODS: Patients were given antiandrogen therapy with allylestrenol (50 mg/day) for 16 weeks. The medication was then withheld and the patients were carefully monitored for an additional 16 weeks. There were 34 BPH patients ranging in age from 55 to 82 years (mean, 66.1 years). The efficacy of allylestrenol was evaluated by its effects on prostate volume, maximum urinary flow rate (MFR), and symptom scores at the end of 16 weeks of treatment and then again at 32 weeks (16 weeks after cessation of therapy). RESULTS: Allylestrenol was effective in the treatment of BPH, and was still effective 16 weeks after the cessation of medication. The prostate volume did not change after treatment cessation nor did the total symptom score, but the MFR reversed to the pretreatment level. Serum testosterone (1.95 ng/mL), dihydrotestosterone, and gonadotropin levels decreased on therapy, but were completely reversed by the end of this study. A prostate needle biopsy revealed that after 16 weeks without therapy, some glands showed regressive glandular changes, while some glands showed slight hyperplastic changes of the secretory epithelium. Eight per cent of patients complained of loss of libido during this study. CONCLUSIONS: Allylestrenol is an effective and safe medical treatment for patients with symptomatic BPH. Hormonal and histopathologic findings suggest that the prostate gland may regrow after discontinuation of medication.

Aged↗

Skin penetration enhancing action of cis-unsaturated fatty acids with omega-9, and omega-12-chain lengths.

The skin penetrative action of high purity cis-omega-12-octadecenoic acid (petroselinic acid, HP-PSA) on rat skin was compared with that of high purity cis-omega-9-octadecenoic acid (oleic acid, HP-OA), following treatment of rat intact skin surface with either 0.05 M HP-PSA or HP-OA in propylene glycol (PG), using Fourier transform/attenuated total reflection (FT-IR/ATR) analysis. Both HP-PSA and HP-OA disordered the lipid structures of the stratum corneum region to a similar extent. Removal of the extractable lipids of the stratum corneum region was marked with HP-PSA/PG but was very slight upon HP-OA/PG treatment. The spectra of the amide II region which originated from proteins suggests that HP-PSA/PG more rapidly disordered the protein structures of both the stratum corneum and the dermis than HP-OA/PG. However, the extent of disordering of the protein structures was presumed to be similar between these two skin penetration enhancers at the maximum level. Enhancement of PG flux in the dermis showed strong positive correlation with the degree of dermis-disordering action of HP-PSA/PG and HP-OA/PG. These results demonstrate that HP-PSA, which has a double bond at an even numbered position (omega-12), more rapidly affects the perturbation of the structures of both the stratum corneum and the dermis than HP-OA, which has the double bond at an odd numbered position (omega-9). Differences in the physicochemical properties of HP-PSA and HP-OA which originate from differences in the double bond position most likely determine the efficacy of these compounds as skin penetration enhancers.

Animals↗

Effects of YM175, a new-generation bisphosphonate, on hypercalcemia induced by tumor-derived bone resorbing factors in rats.

YM175 (disodium cycloheptylaminomethylenediphosphonate monohydrate) is a new-generation bisphosphonate with stronger inhibitory activity on bone resorption than first-generation bisphosphonates. In the present study, the effect of YM175 on hypercalcemia induced in rats by single administration of either parathyroid hormone-related protein (PTHrP) or concomitant administration of PTHrP and interleukin 1beta (IL-1beta) was investigated. YM175 (0.01-1 mg/kg, i.v.) inhibited the increase in serum free calcium concentration induced by continuous administration of PTHrP alone (3 microg/rat/day, s.c., 7 days) dose-dependently. The inhibitory effect of YM175 appeared the day after administration and remained 3 days after administration. The effect of YM175 reached a maximum 2 days after administration, at which time the ED50 value of YM175 was calculated to be 0.041 mg/kg, i.v., revealing a potency approximately 50- and 10-fold stronger than those of either pamidronate or alendronate, respectively. In contrast, elcatonin (1-10 units/kg, s.c.) only transiently inhibited PTHrP-induced free calcium increase. YM175 (0.1-3 mg/kg, i.v.) also inhibited the increase in the serum free calcium concentration induced by continuous concomitant administration of both PTHrP and IL-1beta in a dose-dependent manner. These results indicated that YM175 is expected to be a useful drug for hypercalcemia associated with malignant tumors due to its efficacy and range of effect.

Animals↗