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Biomedical subjects

Y Murakami

Publications and source records attributed to Y Murakami.

At least 199 records · Page 11Linked to original sources
PubMed2000

The susceptibility of culture cells to avian influenza viruses.

The susceptibilities of culture cells to twelve avian influenza virus strains were determined with ten established cell lines including MDCK and ESK cells and three primary culture cells. The established cell lines derived from embryonic swine kidney (ESK) and chicken kidney (CK) primary culture cells were more sensitive to the avian influenza viruses than the other eleven cells. The ESK cell had a particularly higher infective titer than the MDCK cell with and without trypsin supplement in culture medium, and dispersion of the infective titers was narrower than that of the MDCK cell. The ESK cell is a suitable candidate for routine work on avian influenza viruses in laboratories.

Animals↗
PubMed2000

Immunohistochemical analysis of cyclin A, cyclin D1 and P53 in mammary tumors, squamous cell carcinomas and basal cell tumors of dogs and cats.

The involvement of cyclin A, cyclin D1 and p53 proteins in canine and feline tumorigenesis was analyzed immunohistochemically. In the present study, a total of 176 cases were examined, among which there were 108 canine cases (75 mammary lesions, 16 squamous cell carcinomas and 17 basal cell tumors) and 68 feline cases (43 mammary lesions, 20 squamous cell carcinomas and 5 basal cell tumors). Speckled nuclear staining for cyclin A was observed in 19/38 (50%) canine malignant mammary tumors and 18/37 (48.6%) feline mammary carcinomas, while this was not seen in benign mammary tumors of either dogs or cats. Marked intense nuclear cyclin A staining was seen in 7/16 (43.8%) canine squamous cell carcinomas and 18/20 (90.0%) feline squamous cell carcinomas. Only 3/17 (17.6%) canine basal cell tumors showed slight and scattered staining for cyclin A. Expression of cyclin D1 was very rare in both canine and feline tumors. Nuclear staining of p53 was found in 7/37 (18.9%) feline mammary carcinomas. Intense immunoreactivity for p53 was found in 6/16 (37.5%) canine squamous cell carcinomas and 8/20 (40%) feline squamous cell carcinomas. These results suggest that cyclin A may have a role in the proliferation of canine malignant mammary tumors, feline mammary carcinomas and squamous cell carcinomas of dogs and cats, and p53 may associate with the tumorigenesis of feline mammary carcinomas and squamous cell carcinomas of dogs and cats.

Animals↗
PubMed2000

Amplification of the cyclin A gene in canine and feline mammary tumors.

DNAs from 33 canine mammary tumors and 8 feline mammary carcinomas were examined by Southern blot analysis to clarify genomic abnormalities of the cyclin A gene. Amplification of cyclin A was detected in 27.3% (9/33) of canine mammary tumors and 87.5% (7/8) of feline mammary carcinomas. It was suggested that amplification of cyclin A do not correlate directly with the tumorigenesis of canine mammary tumors, because there was no significant difference of incidence of cyclin A amplification between the benign and malignant tumors. In feline mammary carcinomas, the high frequency of cyclin A amplification raised the possibility that the amplification lead to the protein overexpression and play an important role in the tumorigenesis.

Adenocarcinoma↗
PubMed2000

Application of latex beads agglutination test for the detection of the antibody against virus-infection-associated (VIA) antigen of foot-and-mouth disease (FMD) virus.

Latex beads agglutination (LA) for the detection of the antibody against virus infection-associated (VIA) antigen of foot-and-mouth disease (FMD) virus was estimated using experimentally infected animals. The VIA antibody titer by the LA test were compared with the neutralization titer and the titer by agarose gel diffusion (AGD) test, which has been used as a standard method for VIA antibody titration. The latex beads were coated with VIA antigen in carbonate buffer solution (0.5 M, pH 9.6) for the test. The sensitivity of the LA test was clearly higher than that of the AGD test in the results for cattle and swine infected experimentally. The antibody was detected in the bovine serum obtained at the 13th week after inoculation by the LA but not by the AGD test. The LA test appears to be simple, rapid and sensitive for the detection of the antibody of FMD virus in the surveillance of FMD and the FMD quarantine of imported animals.

Animals↗
PubMed2000

Twenty-kilodalton human growth hormone (20K hGH) secretion from growth hormone-secreting pituitary adenoma cells in vitro.

Circulating human growth hormone (GH) consists of several molecular isoforms. Increased proportion of circulating non-22K hGH and 20K hGH was reported in active acromegaly. In this study, we studied the release of 20K and 22K hGH from cultured GH-producing human pituitary adenoma cells in vitro. Pituitary adenoma cells obtained from 6 acromegalic patients were cultured and submitted to perifusion experiments. Concentrations of 20K and 22K hGH in the serum and the perifusion effluent were determined by specific enzyme-linked immunosorbent assays recently developed. The %20K value varied in a wide range from 3.58 to 8.72% in vitro and was lower than in the serum (mean+/-SD: 6.57+/-1.88% vs 9.08+/-2.12%, P<0.05). There was no correlation between the %20K values in vitro and in vivo (r=0.31, P>0.05). The in vitro secretions of 20K and 22K hGH were in parallel and strongly correlated (r=0.953, P<0.001). These findings suggest that different GH-producing pituitary adenoma cells secrete 20K hGH in variable amounts and that the proportion of 20K hGH in the serum might be affected by metabolic clearance of hGH isoforms. It was also suggested that 20K and 22K hGH might be secreted in toto from GH-producing human pituitary adenoma cells.

Acromegaly↗
PubMed2000

Reverse correlation between urine nitric oxide metabolites and insulin resistance in patients with type 2 diabetes mellitus.

We studied the possible relationship between nitric oxide (NO) production and insulin resistance in patients with type 2 diabetes mellitus. Urine NO metabolites (NOx) were measured as an index for NO production by HPLC combined with a Cd column, Griess reaction and a spectrophotometer in 403 healthy control subjects and 102 hospitalized patients with type 2 diabetes. Glucose infusion rate (GIR) was measured as a reverse index for insulin resistance by euglycemic glucose clamp study using an artificial pancreas in 20 of 102 diabetic patients. Urine NOx was lower in the patients with type 2 diabetes than in healthy control subjects (mean+/-SE: 3.18 +/-0.02 versus 3.25 +/-0.01 log[-micromol/gCr], p<0.01). Urine NOx was correlated with body mass index (BMI) in 102 diabetic patients (r= -0.372, p<0.001), but not related to either age, sex, fasting plasma glucose, HbA1c or blood pressure. Urine NOx was correlated with GIR independent of BMI in 20 diabetic patients (r=0.774, P<0.0001). These findings suggest that NO production is closely related with insulin resistance in patients with type 2 diabetes.

Adult↗
PubMed2000

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 21). Comparison of the effects of 2- and 4-weeks pyrimethamine treatment in rats.

Pyrimethamine (PYR), clinically used as an antimalarial or antiparasitic agent, is known to exert testicular toxicity in rats on oral administration for 8 weeks. This study was performed to examine whether 2-weeks daily repeated doses of PYR might induce detectable toxicity on the male reproductive organs in rats. PYR was orally administered to Slc:SD male rats at doses of 12.5, 25 or 50 mg/kg for 2 weeks, or 6.25, 12.5 or 25 mg/kg for 4 weeks. No effects were seen in any group on physical examination and body weight measurement. Gross findings in autopsy exhibited no abnormalities in any of the animals. There were no meaningful changes in the weights of reproductive organs, or in the number and activity of sperm in the epididymides. Loss and degenerative changes of pachytene spermatocytes in stages I to III seminiferous tubules were observed in the rats given 50 mg/kg PYR for 2 weeks. From the results obtained, it is concluded that 2-weeks repeated dosing with PYR is sufficient to detect toxicity on male reproductive organs in rats using histopathological examination.

Administration, Oral↗
PubMed2000

Different mechanisms of acquired resistance to fluorinated pyrimidines in human colorectal cancer cells.

5-Fluorouracil (5-FU), 5-fluoro-2'-deoxyuridine (FdUrd) and 5-trifluorothymidine (F3(d)Thd) are antimetabolites which are metabolized to their corresponding active forms which inhibit DNA synthesis via inhibition of thymidylate synthase (TS). To investigate ways of overcoming 5-FU-resistance, we established acquired-resistant colorectal cancer cell lines against these three drugs by continuous and step-wise escalation of drugs, and analyzed the cytotoxicity and the mechanism of resistance to the drugs. When cells were incubated with the 3 drugs for 72 h, the resistance ratio to parental DLD-1 human colorectal tumor cells was 65.2 for DLD-1/5-FU, 9.7 for DLD-1/FdUrd and 448.6 for DLD-1/F3(d)Thd cells. DLD-1/5-FU cells did not show any cross-resistance against FdUrd and F(3)dThd. However, DLD-1/FdUrd cells showed 3- and 9-fold increased resistance to 5-FU and F3(d)Thd, respectively, and DLD-1/F3(d)Thd cells also showed about 90-fold resistance to FdUrd. Analysis of enzyme activities and gene expression associated with pyrimidine metabolism indicated that a significant decrease in orotate phosphoribosyltransferase activity in DLD-1/5-FU cells, a 7-fold increase of TS mRNA in DLD-1/FdUrd cells, and a 37-fold decrease in thymidine kinase activity of DLD-1/F3(d)Thd cells were the major mechanisms of drug resistance. These findings were closely associated with the cytotoxicity of 5-FU, FdUrd and F3(d)Thd against the established 5-FU-, FdUrd- or F3(d)Thd-resistant cells. When DLD-1/FdUrd cells expressing increased TS mRNA were treated with FdUrd and F3(d)Thd for only 4 h, the resistance ratios of DLD-1/FdUrd cells to parental DLD-1 cells were markedly different for FdUrd and F3(d)Thd, suggesting that the cytotoxicity with short-time exposure to F3(d)Thd is due to a mechanism other than TS inhibition, although the cytotoxicity of F3(d)Thd in the short-time is low compared to that of long-time exposure. In conclusion, F3(d)Thd, an antimetabolite that inhibits TS activity, may be effective against 5-FU and/or FdUrd-resistance in colorectal cancer cells caused by amplification of TS and/or deletion of orotate phosphoribosyltransferase.

Antimetabolites, Antineoplastic↗
PubMed2000

[Histopathological study of the temporal bones in patients with primary carcinomas of the ear].

The most common symptoms of patients with carcinomas of the middle ear or mastoid are otorrhea, facial paralysis, and hearing loss, including a sensorineural element and vertigo. The latter two symptoms are indicators of inner ear damage. However, few reports have been made concerning the histopathological changes that occur in the inner ear in the presence of a tumor. The present study was performed to determine the pattern of tumor invasion in the inner ear and the histopathological changes that occur in the inner ear in cases of ear carcinomas. Temporal bone sections from five patients (age: #39-73 years; 3 males and 2 females) who died from a primary carcinoma of the ear were studied histologically. The following features were examined: 1) localization of the tumor in the temporal bone, 2) pattern of tumor invasion in the inner ear, 3) pathological changes in the inner ear, including the cochlea, vestibule and semicircular canals. Tumor cells were still present in the temporal bone sections of all the patients except one, even though the patients had received various treatments for the carcinoma, including radiation therapy, surgery and chemotherapy. Marked inflammatory and necrotic changes were observed in cases where the tumor had invaded the external auditory canal, middle ear cleft, internal auditory canal, and in some cases the inner ear. In cases where the tumor invaded the inner ear via the internal auditory canal rather than directly from the middle ear, the otic capsule is thought to have acted as a barrier against tumor invasion. In addition, marked degenerative changes throughout the entire inner ear structures were noted. These changes may have arisen from an attenuated blood supply to the inner ear as a result of pressure from the tumor in the internal auditory canal, tumor infiltration of the labyrinthine artery.

Adult↗
PubMed2000

[Simple evaluation of CT findings in the paranasal sinuses for chronic sinusitis].

The CT scores and scoring for improvement based on them, which we proposed previously, is a simple and highly reproducible method of evaluation of sinus units before and after an operation for chronic sinusitis. We compared this evaluation method with the results of quantitative assay and showed its advantages and disadvantages. The subjects were 258 sinuses in patients who underwent endonasal sinus surgery (ESS) in the department of otolaryngology, Kyoto Prefectural University of Medicine Hospital from April 1996 to April 1997. The subjects were evaluated according to the following 4 grades negligible shadow in the paranasal sinus CT scored 0, less than 50% shadow scored 1, more than 50% of shadow scored 2, and mostly filled with shadow scored 3. Furthermore, the preoperative and postoperative CT scores were compared and the rate of improvement was rated in the following 3 grades: score 0 for unchanged or aggravated subjects, score 1 for subjects showing improved CT score by 1 grade, and score 2 for those showing improved CT score by 2 grades or a postoperative CT score of 0. Quantitative image analysis was input into a personal computer and the ratio occupied by the shadow was calculated, as the shadow ratio. While some discrepancies were seen in parts in the comparison of the quantitative image analysis and CT scores as the former captures minute shadows, a positive correlation was obtained overall. Attention is needed to accurately evaluate small paranasal sinuses such as the frontal sinus, and small amounts of shadow, which are areas where errors may occur. A satisfactory correlation was obtained between the score for the improvement rate and the difference in the shadow ratios before and after surgery. The CT scores and the scores for the improvement rate showed no difference from the results of other evaluation methods reported in the past, and evaluation of similar precision was possible. It was thought that this simple evaluation method of CT findings in the paranasal sinuses, which we examined in the present study, was quite useful as a simple stage-classification method that could be utilized in everyday practice considering its facility, reproducibility and satisfactory precision.

Adult↗
PubMed2000

[Study of matrix metalloproteinase-2 and -9 in thyroid papillary cancer].

Metastasis of cancer starts with the penetration of cancer cells through the membrane surrounding the cancer focus into the stroma (extracellular matrix). The focal membrane consists of mainly type-IV collagen. An immunochemical study of 28 patients with benign thyroid nodular diseases and 27 patients with papillary carcinoma revealed the fragmentation of type-IV collagen in 4 patients with papillary carcinoma. Matrix metalloprotease (MMP)-2 and MMP-9 are the major enzymes which decompose type-IV collagen, and they have been suggested to be related to cancer metastasis. Therefore, we conducted biochemical and immunohistochemical studies to determine the relationship between these MMPs and the degree of malignancy in thyroid diseases. The concentration of MMP-2 in the serum of patients with papillary carcinoma and patients with benign nodules was 526.0 +/- 96.6 and 522.7 +/- 114.6 ng/ml, respectively, and that of MMP-9 was 53.8 +/- 40.3 and 39.9 +/- 36.0 respectively. There was no significant difference between the two groups in the concentration of either enzyme. The concentration of TIMP-2 in the serum was below the detectable level. On the other hand, the concentration of MMP-2 in the tissue of papillary carcinoma, benign nodules and normal tissue was 12.1 +/- 8.1, 5.7 +/- 4.3, and 0.6 +/- 0.5 ng/mg tissue protein, respectively, and that of MMP-9 was 4.2 +/- 4.1, 2.1 +/- 1.7, and 0.4 +/- 0.3 ng/mg tissue protein, respectively. Concentrations of both enzymes were significantly higher in the papillary carcinoma tissue. Immunohistochemical studies revealed a diffuse granular distribution of MMP-2 in the cytoplasm of the tumor cells. These findings imply that MMP-2 and MMP-9 are related to the degree of malignancy of cancer, especially metastasis.

Biomarkers, Tumor↗
PubMed2000

[Value of upper gastrointestinal endoscopic examination of head and neck cancer patients].

Between January 1995 and March 1999, we performed the upper gastrointestinal endoscopic examinations on 287 patients with head and neck cancers and detected 23 cases (8%) of esophageal cancer and 8 cases (2.8%) of gastric cancer, showing how frequently esophageal cancer occurs in head and neck cancer. The esophageal cancer involved the oral cavity in 8 cases (9.5%), the oropharynx in 3 cases (8.6%), the hypopharynx in 10 cases (19.6%), and the larynx in 2 cases (2%). Esophageal cancer occurred most frequently in hypopharyngeal cancer, particularly the pyriform sinus type and the postcricoid type. We conclude that upper gastrointestinal endoscopic examination, including Lugol staining, is necessary in head and neck cancer patients.

Adenocarcinoma↗
PubMed2000

[Evaluation of extraocular muscle enlargement in dysthyroid ophthalmopathy].

PURPOSE: To evaluate the extraocular muscle enlargement in dysthyroid opthalmopathy. METHOD: Extraocular muscle enlargement was assessed by orbital computed tomography (CT) in 573 patients with dysthyroid ophthalmopathy in order to investigate the frequency and exact location of extraocular muscle enlargement and the clinical features of related ocular symptoms in patients with dysthyroid ophthalmopathy. RESULTS AND CONCLUSION: 187 patients (38% of the total) showed evidence of extraocular muscle enlargement on CT images, and this disorder were more frequent in male patients than in female patients. Extraocular muscle enlargement was also more frequently seen in older patients than in younger patients. Enlargement of a single muscle was found in 55% of the 187 patients, with the most frequently affected muscle being the inferior rectus muscle. When multiple muscles were enlarged, the inferior rectus muscle was the most frequently affected, followed by the medial rectus muscle. Of the clinical findings specific to dysthyroid ophthalmopathy examined in the present study, the incidence of exophthaomos, upper lid swelling, superior limbic keratoconjunctivitis, keratitis, diplopia, and dysthyroid optic neuropathy were significantly increased in patients with dysthyroid ophthalmopathy, indicating a close relationship between these findings and the underlying disease, but the incidence of upper lid retraction was not significantly increased.

Adolescent↗
PubMed2000

[Surgical treatment for bilateral multiple lung cancers].

We reviewed 12 patients with contralateral bronchogenic carcinomas. Seven of them had metachoronous carcinomas and 5 had synchronous carcinomas. We treated 3 patients with lobectomy on both lungs, and 4 patients with lobectomy and segmentectomy, 2 patients with lobectomy and wedge resection, 2 patients with segmentectomy and thoracoscopic wedge resection, and one patient with lobectomy and ablation on each lung. Two patients who had lobectomy on both lungs were dead, one of whom of bronchofistula on operation and the other of respiratory failure 7 years and one month after second operation. The 5-year survival rate in 12 patients was 68.5% after first operation and 82.5% after second operation. We conclude that lobectomy on both lungs are not recommended because of high mortality rate and the limited resection should be considered to treat the other contralateral primary lung cancers. Because the patients with primary lung cancers have the possibility to suffer from new primary cancers in the different site of the lung, we need careful follow up of the patients after treatment on the first lung cancer.

Adenocarcinoma↗
PubMed2000

Axial chirality of ortho-substituted N,N-diacylanilines: electronic effects of acyl groups on racemization

Studies on the racemization of optically active ortho-tert-butyl-N,N-diacylanilines 1c-e including the electronic effects of their acyl groups are described. The racemization of 1c bearing a 4-methoxyphenyl substituent occurred faster while that of le bearing a 4-trifluoromethylphenyl substituent was slower, compared with that of 1d bearing a phenyl group. Thus, the rate of racemization depends on the electronic effects of the acyl groups in addition to steric effects of the acyl groups in la, b as reported previously (K. Kondo, H. Fujita, T. Suzuki and Y. Murakami, Tetrahedron Lett. 1999, 40, 5577-5580).

Journal Article↗
PubMed2000

Generation of pro-inflammatory and anti-inflammatory cytokines in the gut in zymosan-induced peritonitis.

In major systemic inflammation such as severe peritonitis, various pro-inflammatory cytokines, such as TNF-alpha, IL-1 beta and IL-6, play important roles in the development of multiple organ dysfunction syndrome (MODS). The purpose of this study was to investigate the outflow of pro-inflammatory and anti-inflammatory cytokines from the efferent mesenteric lymphatic vessels under peritonitis. Mesenteric lymph samples were collected from adult male rats at 2, 4, 6, 8 and 10 hr after an intraperitoneal injection of zymosan at a dosage of 0.1 mg/g (non-lethal dose) or 0.5 mg/g (lethal dose). Blood samples were obtained at 10 hr after zymosan administration. The amounts of drained TNF-alpha and IL-6 in the lymph peaked at 2-4 hr and 4-8 hr after zymosan administration, respectively. The amounts of drained IL-10 in the lymph gradually increased until 10 hr. The amounts of drained TNF-alpha and IL-10 in the mesenteric lymph were significantly correlated with the dosage of zymosan. In conclusion, under intraperitoneal inflammation, pro-inflammatory cytokines (TNF-alpha and IL-6) increased in the mesenteric lymph and were drained into circulation. IL-10, one of the anti-inflammatory cytokines, also increased in the mesenteric lymph after several hours' delay and its increase was remarkable in several inflammations. These findings suggested that the gut might be one of the pro-inflammatory and anti-inflammatory cytokine-generating organs under peritonitis. The lymph-drained amounts of each cytokine under peritonitis are considered to differ with the time or severity of inflammation, which may cause different conditions in patients due to the imbalance of pro-inflammatory and anti-inflammatory cytokines.

Animals↗
PubMed2000

[Relationship between endothelial function and female hormone level in very old females: evaluation from ischemic reactive hyperemic response in forearm vessels].

Recently, the mechanism of longevity in females was proposed to be associated with female hormones. This study examined the effect of aging and sex on vascular endothelial function, and the relationship between female hormone level and endothelial function by ischemic reactive hyperemic response in the forearm using plethysmography. The study population consisted of 246 healthy subjects aged from 20 to 76 years (119 males, 127 females) and 20 healthy females aged 85 years and older (85 to 103 years; mean age 94 years) without distinct cardiovascular disease, hypertension, diabetes mellitus, renal disease, liver dysfunction or anemia. Levels of the female hormones, estradiol and estriol, were measured in females aged more than 85 years. The duration of reactive hyperemia decreased with aging, but the difference between males and females was not significant at any age. In females, the duration was markedly decreased from 110 +/- 36 sec in the fifties to 81 +/- 29 sec in the sixties or older (p < 0.05). Excess flow also showed similar changes to the duration of reactive hyperemia. The duration of reactive hyperemia and excess flow in females aged 85 years and older were similar to those in the fifties, but was significantly longer than those in females 60 years or older. The concentrations of estradiol (44.9 +/- 27.1 pg/ml) and estriol (22.1 +/- 13.4 pg/ml) in females aged 85 years were higher than in the sixties. There was a positive correlation between the duration of reactive hyperemia and the concentration of estradiol (r = 0.56, p < 0.01) or estriol (r = 0.57, p < 0.01). In summary, vascular endothelial function was impaired gradually with aging, but preservation of the function in healthy, very old females was closely associated with levels of female hormone.

Adult↗