Biomedical subjects

S Kondo

Publications and source records attributed to S Kondo.

At least 343 records · Page 19Linked to original sources

PubMed1998

The pattern of infiltration at the proximal border of hilar bile duct carcinoma: a histologic analysis of 62 resected cases.

OBJECTIVE: To clarify the importance of different patterns of infiltration at the proximal border of hilar bile duct carcinomas. SUMMARY BACKGROUND DATA: There are few detailed pathologic studies on the proximal resection margins in patients with hilar bile duct carcinoma. METHODS: Serial sections of 62 specimens of resected hilar bile duct carcinoma were examined histologically to determine the involved layers and routes of invasion at the proximal border. The degree of cancer extension was determined, and the relation between the length of the tumor-free resection margin and postoperative anastomotic recurrences was analyzed. RESULTS: Mucosal extension was predominant in papillary and nodular tumors, but submucosal extension was predominant in diffusely infiltrating and nodular-infiltrating tumors. Submucosal extension usually consisted of direct or lymphatic invasion. The mean length of submucosal extension was 6.0 mm. Superficial spread of cancer, defined as mucosal extension of more than 20 mm from the main lesion, was seen in 8 specimens. No patient had an anastomotic recurrence when the tumor-free resection margin was greater than 5 mm. CONCLUSIONS: The pattern of infiltration at the proximal border of resected hilar bile duct carcinomas is closely related to the gross tumor type. The length of submucosal extension is usually less than 10 mm. Superficial spread of cancer is seen in more than 10% of cases. A tumor-free proximal resection margin of 5 mm appears to be adequate in hilar bile duct carcinoma.

Adult↗

PubMed1998

Cutaneous disseminated actinomycosis in a patient with acute lymphocytic leukemia.

Actinomycosis is an uncommon infectious disease caused predominantly by Actinomyces israelii. The cutaneous disseminated form is usually caused by hematogenous dissemination from a primary extra-cutaneous lesion. We report here cutaneous disseminated actinomycosis without any detectable extra-cutaneous lesions in a 42-year-old Japanese woman with acute lymphocytic leukemia. Multiple soft nodules developed on her upper and lower extremities. Histopathological examination revealed "sulfur granules", which are a specific finding for actinomycosis. Cultures from biopsy specimens were not successful. There were no cervicofacial, thoracic, nor abdominal lesions. These findings suggest that cutaneous disseminated actinomycosis in our patient developed primarily in the skin. Although the patient was immunocompromised, antibiotic treatment with minocycline was effective.

Actinobacillus↗

PubMed1998

Pretibial myxedema with Graves' disease: a case report and review of Japanese literature.

We report a case of pretibial myxedema with Graves' disease in an 18-year-old Japanese woman. The physical examination revealed waxy indurated plaques with prominent hair follicle openings and nonpitting edema disseminated on her lower legs. Histology from an edematous lesion revealed that the dermis was markedly thickened with abundant mucin, especially hyaluronic acid, and the collagen fibers in this portion were splitting up into fibrils. We also reviewed 112 cases of pretibial myxedema reported in the Japanese literature.

Adolescent↗

PubMed1998

Contact dermatitis due to sodium colistimethate.

Colistin methanesulfonate sodium (CLMS) is a widely-used antibiotic. To our best knowledge, only two cases of contact allergy to CLMS have been reported. We described a 4-year-old girl with contact dermatitis evoked by CLMS that had been applied as an ophthalmic solution. The dermatitis started after administration for 21 days. The diagnosis was confirmed by as is and constituent patch tests. We reviewed the literature in which contact allergy due to CLMS and colistin sulfate is described.

Anti-Bacterial Agents↗

PubMed1998

A case of infantile digital fibromatosis with spontaneous regression.

We reported a fourteen-month-old boy with infantile digital fibromatosis. At the age of seven months, a nodule appeared on the back of the left third toe, and developed into a slight red tumor divided into five hemispherical nodules. Histopathologically, spindle-shaped tumor cells with an eosinophilic inclusion body in the cytoplasm were seen in the dermis. Electron microscopy showed a dense body in the cytoplasm of the tumor cells. One year and two months after the first visit, the tumor regressed without any aggressive treatment. Japanese cases of infantile digital fibromatosis were reviewed. The literature review and our case suggest that the tumor should be observed without any aggressive treatment unless it causes mobile dysfunction of the affected finger or toe.

Diagnosis, Differential↗

PubMed1998

Morphological alterations of Saccharomyces cerevisiae induced by benanomicin A, an antifungal antibiotic with mannan affinity.

The effects of benanomicin A, a mannose-binding antifungal antibiotic, on yeast cells of Saccharomyces cerevisiae were studied by electron microscopy. Cytological studies using vital stain with methylene blue demonstrated that benanomicin A at 20 and 80 microg/ml killed buds in preference to parent cells. In confirmation, examination by TEM revealed that benanomicin A at 80 microg/ml damaged buds more severely than parent cells. The major effect on the ultrastructure was characterized by severe damage to the cell membrane. In addition, it caused expansion and vacuolation of the endoplasmic reticulum (ER), and partial fragmentation and disappearance of nuclear membranes. The membrane-disruptive activity of benanomicin A may be closely associated with its membrane affinity.

Anthracyclines↗

PubMed1998

Mortality and cancer incidence in Misasa, Japan, a spa area with elevated radon levels.

A historical cohort study was conducted in Misasa town, Tottori prefecture, Japan, where radon spas have been operating for a long time. Misasa town was divided into an elevated radon level area and a control area, with mean indoor radon levels of about 60 and 20 Bq/m3, respectively. In total, 3,083 subjects in the elevated radon level area and 1,248 in the control area, all aged 40 or older on January 1, 1976, were followed up until December 31, 1993, for a mean period of 14 years. The mortality rates from all causes exhibited no difference between the elevated radon level area and the control area for both sexes. No difference was observed in the incidence of all-site cancers (age, period-adjusted rate ratios by Poisson regression, RR = 1.06, 95% confidence interval (CI) 0.79-1.42 for males, RR = 0.90, 95% CI 0.65-1.24 for females), while stomach cancer incidence seemed to decrease for both sexes (RR = 0.70, 95% CI 0.44-1.11 for male, RR = 0.58, 95% CI 0.34-1.00 for female) and lung cancer incidence for males only seemed to increase (RR = 1.65, 95% CI 0.83-3.30 for male, RR = 1.07, 95% CI 0.28-4.14 for female) in the elevated radon level area. Caution is needed in the interpretation of these findings, however, since the individual exposure level was not measured and major confounding factors, such as smoking and diet, could not be controlled in this study.

Adult↗

PubMed1998

Development of high-grade renal cell carcinomas in rats independently of somatic mutations in the Tsc2 and VHL tumor suppressor genes.

Ferric nitrilotriacetate (Fe-NTA) induces renal proximal tubular damage that ultimately leads to a high incidence of renal cell carcinoma (RCC) in rats. The RCCs are characterized by 1) high incidence of pulmonary metastasis and peritoneal invasion, 2) high incidence of tumor-associated mortality and 3) possible involvement of reactive oxygen species in carcinogenesis. The present study investigated the possible role of Tsc2 and VHL tumor suppressor genes in this model. Thirty-four Fe-NTA-induced primary RCCs and 20 other primary or metastatic tumors of rats were searched for genetic alteration in all the coding exons of both genes by polymerase chain reaction-single-strand-conformation polymorphism analysis and sequencing in conjunction with morphological evaluation. In the Fe-NTA-induced RCCs, frequency of metastasis or invasion was proportionally associated with the nuclear grade of the tumor (grades 1-3). Only one Fe-NTA-induced RCC of grade 1 revealed missense mutations with loss of heterozygosity in exon 10 of the Tsc2 gene (codons 334, GTG (Val) to GCG (Ala), and 336, TAT (Tyr) to CAT (His). No mutation was found in the VHL gene. The results suggest that 1) high-grade RCCs can develop in the absence of mutations in the Tsc2 and VHL genes in rats, and that 2) Tsc2 gene somatic mutation can nonetheless be one of the causes of non-Eker rat RCCs.

Animals↗

PubMed1998

High Fas ligand expression on lymphocytes in lesions of ulcerative colitis.

BACKGROUND: The pathogenesis of ulcerative colitis is unclear, but cytotoxic T lymphocytes infiltrating the mucosa have been implicated in mucosal damage. The Fas ligand (FasL), expressed on cytotoxic T lymphocytes, induces apoptosis in cells expressing Fas. AIM: To analyse FasL expression in affected colonic mucosa to ascertain Fas-FasL interaction in ulcerative colitis. METHODS: FasL mRNA was quantified in colonic mucosal specimens from healthy subjects and patients with ulcerative colitis or Crohn's disease, using the competitive reverse transcription polymerase chain reaction. FasL mRNA localisation was determined by in situ hybridisation. Expression of Fas in colonic mucosa was analysed immunohistochemically. Phenotypes of lamina propria lymphocytes that expressed FasL were analysed by flow cytometry. RESULTS: FasL mRNA was strongly expressed in active ulcerative colitis lesions, but not in those associated with active Crohn's disease or active proctitis-type ulcerative colitis. In situ hybridisation showed that FasL mRNA expression occurred in mononuclear cells infiltrating lesions. Fas was expressed in epithelial cells in ulcerative colitis and Crohn's disease, and in normal subjects. Cytometry showed that FasL was expressed in CD3 lymphocytes infiltrating the lamina propria in active lesions. CONCLUSIONS: FasL is expressed in CD3 lymphocytes infiltrating into ulcerative colitis but not Crohn's disease lesions, suggesting that Fas-FasL induced apoptosis participates in the mucosal damage of ulcerative colitis.

Acute Disease↗

PubMed1998

Eccrine syringofibroadenoma: report of a case and analysis of cytokeratin expression.

Eccrine syringofibroadenoma (ESFA) is a rare disorder which shows differentiation toward the eccrine sweat apparatus. There is a controversy concerning the pathogenesis and precise differentiation of this tumor. We report a case of ESFA and its differentiation pattern by an analysis of cytokeratin expression. Using paraffin-embedded materials, histopathological and immunohistochemical studies were performed. Staining patterns of the luminal, peripheral, and inner cells of the tumor strands closely matched or mimicked those of the luminal, outer and intermediate cells of the normal eccrine dermal duct, respectively. The case of ESFA reported revealed a pattern of differentiation suggestive of an eccrine duct origin.

Adenoma, Sweat Gland↗

PubMed1998

Basal cell carcinoma within vulvar Paget's disease.

An 85-year-old Japanese woman had noticed erythema on her vulvar region 3 years before. The erythema gradually increased in size and followed erosion and ulceration with pigmentation on the edge of the erythema. A skin biopsy from the pigmented area showed large round cells with ample cytoplasm, which formed nests or glandular structures. In the dermis there was mass formation of basophilic cells and peripheral cells in a palisade arrangement. The tumor cells in the epidermis showed positive immunoreactivity for carcinoembryonic antigen; on the other hand, the dermal tumor was negative. We diagnosed that the tumor in the epidermis was vulvar Paget's disease, and the dermal tumor was a solid type of basal cell carcinoma. We speculate that the vulvar Paget's disease preceded and then the basal cell carcinoma developed in the area of Paget's disease. This is the first report in which basal cell carcinoma in the area of Paget's disease was documented.

Aged↗

PubMed1998

Apoptosis of medial smooth muscle cells in the development of saccular cerebral aneurysms in rats.

BACKGROUND AND PURPOSE: Using an animal model, we examined the role of apoptosis in the disappearance of medial smooth muscle cells (SMCs) during the development and growth of cerebral aneurysms. METHODS: Various degrees of cerebral aneurysms were induced in the right anterior cerebral artery-olfactory artery bifurcations in 65 Sprague-Dawley rats with ligation of the left common carotid artery and renal hypertension. We performed in situ end labeling of fragmented DNA with the lesions in 45 rats and electron microscopic study in the other 20 rats. RESULTS: With in situ end labeling of fragmented DNA, 4+/-3 apoptotic medial SMCs were detected in 35 of the 45 bifurcations. Apoptotic SMCs appeared in the medial layer in the "preaneurysm" group, the site speculated to show an aneurysmal change in the near future (6+/-3), and in the media in the "early aneurysm" group, which showed characteristics such as a small depression (5+/-3). In the "progressive aneurysm" group, they appeared more frequently at the aneurysmal neck (3+/-2) than the dome (1+/-1). By electron microscopic study, shrunken medial SMCs exhibiting morphological apoptotic changes such as chromatin condensation and fragmentation of the cytoplasm and nucleus were observed in the preaneurysm and early aneurysm groups and at the neck portion in the progressive aneurysm group. In the aneurysmal dome, SMCs showed late characteristics of apoptosis such as more advanced nuclear and cytoplasmic condensation and formation of apoptotic bodies. CONCLUSIONS: The present findings indicate that there is an association between apoptosis of medial SMCs and the formation of saccular cerebral aneurysms.

Aneurysm↗

PubMed1998

Identification of three hydroxysteroid sulfotransferase isoenzymes in the rat liver.

Isolation of several hydroxysteroid sulfotransferase (HS-ST) cDNAs from the rat liver cDNA library has demonstrated the possible expression of these HS-ST isoforms in rat liver. We devised a method to detect unequivocally ST-20 and ST-40 mRNAs by a reverse transcription-polymerase chain reaction, using specific primers. ST-40 mRNA was expressed only in liver, but ST-20 mRNA was present predominantly in the liver and slightly in extrahepatic tissues. On chromatofocusing, expressed ST-20 or ST-40 enzymes were eluted at approx. pH 8.2 and 5.7-4.7 or at pH 6.4-5.4, respectively. Chromatofocusing of adult female rat liver cytosols resolved HS-ST isoenzymes in a broad range of pH, and ST fractions A, B, C, D and E were eluted at approx. pH 8.2, 7.6, 7.5-6.8, 6.2 and 6.1-5.5, respectively. After PAP-agarose affinity column chromatography and SDS-polyacrylamide gel electrophoresis (PAGE), their N-terminal amino acid sequences were determined. ST isoenzymes present in fractions B and E showed identical N-terminal amino acid sequences with those of ST-21 and ST-20, respectively, whereas the ST isoenzymes present in fractions C and D had the same N-terminal amino acid sequence as those of ST-40 (and/or ST-41). The results demonstrated the presence of at least three HS-ST isoenzymes in adult female rat liver.

Amino Acid Sequence↗

PubMed1998

Synthesis and sedative-hypnotic effects of N3-allyl- and N1-allyl-5,6-substituted 2-thiouracil derivatives in mice.

Twenty four thiouracil derivatives, including N3-allyl- (19) and N1-allyl-2-thiouracil (20) were synthesized and their pharmacological effects [sedative-hypnotic activity (loss of righting reflex and spontaneous activity), convulsant activity, effect on pentobarbital (PB)-induced sleep and mortality] were evaluated in mice at doses of 320 mg/kg, i.p. and 2 mumol/mouse by intracerebroventricular (i.c.v.) injections, respectively. N3-Allyl-6-propyl-2-thiouracil (3), N3-allyl-5,6-dimethyl-2-thiouracil (10), N3-allyl-1,2,3,4,5,6,7,8,9-nonahydro-4-oxo-2-thiocyclohepta [d]pyrimidine (16) and N3-allyl-5-methyl-2-thiouracil (18) exhibited sedative-hypnotic activity, whereas N3-allyl-6-ethyl-5-methyl-2-thiouracil (11), N1-allyl-5-methyl-2-thiouracil (21), N1-allyl-1,2,3,4,5,6,7,8,9-nonahydro-4-oxo-2-thiocyclohepta[ d]pyrimidine (23) and N1-allyl-5,6-dimethyl-2-thiouracil (24) conversely displayed clonic- and/or tonic-convulsant seizures. N3-Allyl-6-propyl-2-thiouracil (3) and N3-allyl-5-methyl-2-thiouracil (18) decreased spontaneous activity. Other compounds examined were inactive, or only slightly active in the sedative-hypnotic assay even at high doses. Fifteen compounds (1-4, 7, 10, 11, 14-16, 18-21, and 23) significantly prolonged the PB-induced sleeping time. Interestingly, only N1-allyl-5,6-dimethyl-2-thiouracil (24) shortened the PB-induced sleeping time. These results showed that these thiouracils possessed many different effects such as sedative-hypnotic, anticonvulsant and/or convulsant, and that N3-allyl-5-methyl-2-thiouracil (18) and N1-allyl-5,6-dimethyl-2-thiouracil (24) had the most potent hypnotic activity and antagonistic effect against PB, respectively.

Animals↗

PubMed1998

Mechanochemical solid-state polymerization. IX. Theoretical analysis of rate of drug release from powdered polymeric prodrugs in a heterogeneous system.

We theoretically derived the rate equation of drug release from a simple model in a heterogeneous system. Four assumptions were used to simplify the model. Two kinds of rate equations for drug release derived from two possible limiting cases, that the rate-determining step is a diffusion or hydrolysis controlled process, can predict the experimental results up to 50% hydrolysis. However, the predictions at the later stage by these equations are insufficient. These results suggest that the process of drug release from powdered polymeric prodrugs in a heterogeneous system must be described by both diffusion and hydrolysis. The rate equation derived from a model considering both the diffusion and hydrolysis processes can successfully predict the experimental results for several kinds of polymeric prodrugs. It is also shown that the diffusion coefficient and rate constant for hydrolysis calculated from this equation thoroughly express the character of the comonomer. The rate equation derived from the model that considers both diffusion and hydrolysis is very useful to analyze drug release from various kinds of polymeric prodrugs in a heterogeneous system.

Hydrolysis↗

PubMed1998

Mechanochemical solid-state polymerization. VIII. Novel composite polymeric prodrugs prepared by mechanochemical polymerization in the presence of pharmaceutical aids.

We carried out the mechanochemical polymerization of methacryloyl derivatives of acetoaminophen and 5-fluorouracil in the presence of lactose. The reaction proceeded readily and the polymeric prodrugs were quantitatively produced. This method produces powdered polymeric prodrugs in which fine particles of lactose are homogeneously dispersed, since the reaction proceeds quantitatively through a totally dry process. It is difficult to prepare such a powdered polymeric prodrug by conventional solution polymerization. The rate of drug release of polymeric prodrugs increases with increasing content of lactose, as is shown to be true of the specific surface of polymeric prodrugs. These results suggest that lactose is homogeneously dispersed in powdered polymeric prodrugs. The present method seems applicable to a wide variety of pharmaceutical aids. If one takes the physiochemical property of pharmaceutical aids into consideration, novel polymeric prodrugs with a variety of drug release rates can be synthesized simultaneously with mixing.

Acetaminophen↗

PubMed1998

Effect of an atypical adrenergic beta3-agonist, GS-332: sodium (2R)-[3-[3-[2-(3-chlorophenyl)-2-hydroxyethylamino]cyclohexyl]phenoxy] acetate, on urinary bladder function in rats.

We have developed an atypical adrenergic beta3-agonist, GS 332: Sodium (2R)-[3-[3-[2-(3 Chlorophenyl)-2-hydroxyethylamino]cyclohexyl]phenoxy]acetate, which has an unique structure compared to other beta3 agonists. In vitro study, we compared effects of GS 332 on rat urinary bladder muscle strip contractility with those of clenbuterol hydrochloride (clenbuterol), an adrenergic beta2 agonist. GS-332 relaxed isolated rat urinary bladder strips in a concentration dependent manner with 50% effective concentration (EC50) of 15.7 nM, and the relaxant activity of GS 332 was as potent as that of clenbuterol(EC50; 30.8 nM). The concentration response curve of GS 332 on isolated rat urinary bladder was competed by a specific beta3-antagonist, SR59230A in a concentration-dependent manner, in which Schild slope was 1.1 and pA2 value of SR59230A was 7.1. In vivo study, cystometory investigated in anesthetized rats demonstrated that GS 332 was more potent in increasing the urinary storage volume than clenbuterol and less potent in inhibiting the contractile force of urinary bladder at micturition reflex than clenbuterol. These data demonstrate that GS 332, a new adrenergic beta3-agonist, may be more useful to maintain continence than clenbuterol, an adrenergic beta3 adrenergic agonist.

Adrenergic beta-Agonists↗

PubMed1998

Crown structure of the maxillary molars in the Japanese shrew mole, Urotrichus talpoides (Insectivora, Talpidae).

The maxillary first and second molars (M1 and M2) in the Japanese shrew mole, Urotrichus talpoides, were investigated using an odontometrical approach. The mesiodistal crown diameter was larger in M1 than in M2, while the buccolingual diameter of M1 was nearly equal to that of M2. M2 was more compressed mesiodistally than M1. M1 had a large distal triangle on the stylar shelf. The mesial triangle of M2 was slightly larger than the distal triangle. Despite being smaller than M1, M2 was less variable than M1 in terms of size. The distal triangle of M1 and the mesial triangle of M2 were well developed, and thus this area, which corresponds to the inflection point of the maxillary dental arch, was most likely the center of an occlusal function.

Animals↗