Search PubMed⌕ Search

Biomedical subjects

K Tajiri

Publications and source records attributed to K Tajiri.

At least 19 recordsLinked to original sources
PubMed1998

Role of medullasin in nifedipine-induced gingival overgrowth in rats.

To clarify the possible pathophysiological role of medullasin, a neutrophil elastase-like proteinase, in nifedipine (NF)-induced gingival overgrowth, a rat model of gingival overgrowth was first established using a diet containing NF. The relation between histopathological changes and the distribution of the proteinase was then investigated. Thirty-two, specific pathogen-free 20 day-old, male, Fisher 344 rats were fed a diet containing NF and killed at 2, 8, 16 and 32 weeks. Control rats (n = 32) were fed the same diet but without the drug. The mandible of each rat was resected and sectioned at 4-microm thickness buccolingually between the first and second molars. Computer image analysis was used to evaluate the extent of overgrowth in the approximal gingiva of each sample. To examine medullasin activity, the mean percentage of medullasin-positive cells per total cells counted in the pocket epithelium and the connective tissue adjacent to the epithelium of approximal gingiva was determined immunohistochemically. The height of the mid-portion and the area in NF-treated group increased significantly with time (with the exception of area at 2 weeks) compared with the corresponding regions in the control group. A marked inflammatory-cell infiltration and elongated rete pegs, especially in the mid-portion of approximal gingiva, were seen in the NF-treated group. The mean percentages of medullasin-positive cells in the NF-treated group at 8, 16 and 32 weeks were significantly higher than those of the control. Although medullasin-positive cells were mainly neutrophils, in several samples of the NF-treated group they were recognized as macrophage-like. These findings suggest that medullasin may be involved in host defence and immunoregulation in a NF-induced rat model of gingival overgrowth.

Animals↗
PubMed1998

Common peroneal nerve block for sciatica.

The effectiveness of common peroneal nerve block for lumbar disc herniation was evaluated in a double blind study. Common peroneal nerve block was performed near the fibular head in nine patients using 2% lidocaine and in 10 patients using saline. The average pain scale score decreased from 3.1 to 0.6 in the lidocaine group, whereas it decreased from 3.0 to 2.6 in the placebo group. The average result in the straight leg raising test increased from 61 degrees to 84 degrees in the lidocaine group, but from 44 degrees to 50 degrees in the placebo group. Lower leg pain lessened more in the lidocaine group than in the placebo group. The finding that lower leg pain disappeared or decreased with a lidocaine block at a site far distal to the lumbar lesion suggests that impulses that are transmitted distal to the lesion may be important for the generation of sciatic radicular pain.

Adult↗
PubMed1997

Nonalcoholic steatohepatitis masquerading as autoimmune hepatitis.

Nonalcoholic steatohepatitis is an increasingly recognized clinicopathologic condition. We report two cases of nonalcoholic steatohepatitis in middle-aged Japanese women whose clinical and laboratory data mimicked autoimmune hepatitis. Histologic findings of both cases were definite steatohepatitis with portal and pericellular fibrosis. Both patients' HLA-DR haplotypes were DR4 and DR2, which are frequently observed in Japanese patients with autoimmune hepatitis. Our cases suggest a diversity in the pathogenesis of nonalcoholic steatohepatitis.

Adult↗
PubMed1996

Ischemic hepatitis in cirrhosis. clinical features and prognostic implications.

To characterize liver dysfunction in patients with cirrhosis after variceal bleeding, we analyzed 50 cirrhotic patients who had bleeding esophageal varices with or without shock. Increases in serum total bilirubin levels by 1.5 times were observed within 24 h in 11 of 12 patients with shock who died > 4 days after hemorrhage but in only one of eight patients with shock who survived (p < 0.01). Increases in serum aspartate aminotransferase and alanine aminotransferase by 2.5 times were observed in six patients in the former group but in none of the latter (p < 0.05). In postmortem livers, hepatocellular degeneration with minimal inflammatory cell infiltration was observed. Ischemic hepatitis is frequently noted in cirrhotic patients with ruptured esophageal varices. Patients with increases in the serum level of total bilirubin and/or aminotransferases within 24 h from onset of hemorrhage should be carefully treated even if hemorrhage is controlled.

Adult↗
PubMed1995

Increased renal susceptibility to gentamicin in the rat with obstructive jaundice. Role of lipid peroxidation.

To study whether renal susceptibility to nephrotoxic stimuli is increased in obstructive jaundice, the effect of gentamicin on the renal function in bile duct-ligated rats was investigated. Gentamicin (50 mg/kg/day, subcutaneously) or saline was given to bile duct-ligated rats or sham-operated rats for six days. Mortality in the bile duct-ligated group that received gentamicin was 64% whereas that in the other groups was 0%. In the bile duct-ligated group, although serum creatinine and blood urea nitrogen were minimally affected, focal granulo-vacuolar degeneration in the proximal tubule was observed, which was accompanied by an increase in renal malondialdehyde. Gentamicin significantly increased serum creatinine and blood urea nitrogen levels and caused marked degeneration in the proximal tubule in the bile duct-ligated group, which was accompanied by a further increase in renal malondialdehyde, while these changes were not observed in the sham group. The kidney in obstructive jaundice appears to be susceptible to gentamicin. Enhanced production of oxygen radicals may be responsible for this effect.

Animals↗
PubMed1995

Systemic hypotension and diuresis by L-arginine in cirrhotic patients with ascites: role of nitric oxide.

To investigate the role of nitric oxide in renal function and hemodynamics in cirrhotic patients with ascites, L-arginine (30 g in 300 mL of distilled water), a substrate for nitric oxide synthase, was infused into six cirrhotic patients with ascites, and the effects were compared with those of saline infusion. Healthy controls (n = 5) were also studied under the same conditions. In the patients, L-arginine infusion significantly decreased systolic and diastolic blood pressures while markedly increasing urinary flow and urinary sodium excretion; no significant changes were seen with saline infusion. In controls, only diastolic blood pressure was decreased by L-arginine infusion, whereas urinary flow and urinary sodium excretion were increased by both L-arginine and saline infusion. In both groups, a similar increase of plasma atrial natriuretic factor (ANF) was seen with L-arginine and saline infusions; endothelin and catecholamines were not affected by either infusion. In both groups, plasma levels of vasopressin were increased by L-arginine infusion. In the cirrhotic patients, urinary excretions of cyclic guanosine monophosphate (cGMP) and nitrates/nitrites (NOx) were significantly increased by L-arginine infusion, whereas no significant changes were seen with saline infusion. In controls, only the excretion of cGMP was increased by L-arginine infusion. In summary, L-arginine infusion induces diuresis and natriuresis accompanied by increased excretions of cGMP and NOx in cirrhotic patients with ascites. This differs from the response in controls, where the increase in urinary sodium excretion is not accompanied by an increase in markers of increased nitric oxide synthesis.

Adult↗
PubMed1994

Choledochocele with obstructive jaundice: a case report and a review of the Japanese literature.

A case of a 57-year-old farmer with a rare type of choledochal cyst (choledochocele; Alonso-Lej's type III) is described. The patient was admitted because of obstructive jaundice and acute biliary infection. Abdominal computed tomography scan showed a cystic lesion in the head of the pancreas, and endoscopic retrograde cholangiopancreatography disclosed cystic dilatation of the terminal portion of the common bile duct. It was suspected that the choledochocele could swell and compress the common bile duct, causing obstructive jaundice and acute cholangitis; therefore, it was surgically resected. We also reviewed 61 cases of choledochocele reported in Japan; the findings were similar to those reported in the English literature.

Acute Disease↗
PubMed1994

[A case of advanced gastric cancer with multiple liver metastases showing marked response to new combination chemotherapy using 5-FU, THP and MMC (FTM)].

A 67-year-old man with advanced gastric cancer with multiple liver metastases was treated by a new combination chemotherapy using 5-FU, THP and MMC (FTM). After the first course of FTM, both abnormal liver function and the elevated level of serum CA 19-9 were restored. After the second course of FTM, the primary lesion became a small ulcer around cardia. A partial response was recognized both in the primary lesion and in the liver metastases. No serious side effect was observed except for leukocytopenia, which was controlled by G-CSFS. This new combination chemotherapy (FTM) was suggested to be useful even for far advanced gastric cancer.

Adenocarcinoma↗
PubMed1993

Role of lipid peroxidation in acetaminophen-induced hepatotoxicity: comparison with carbon tetrachloride.

The effect of acetaminophen on lipid peroxidation in vivo and in vitro was studied in rat liver and the data were compared with those with carbon tetrachloride. Carbon tetrachloride increased diene conjugates in vivo and thiobarbituric acid reactive substance production in vitro in the liver microsomal incubation. These changes were further enhanced by ethanol that has previously been shown to increase carbon tetrachloride-induced hepatotoxicity. On the other hand, acetaminophen did not increase diene conjugates in vivo and inhibited thiobarbituric acid reactive substance production in vitro. These effects were minimally affected by ethanol which has previously been shown to inhibit acetaminophen-induced hepatotoxicity. Thus, lipid peroxidation may play a minimal role in acetaminophen-induced hepatotoxicity in contrast with carbon tetrachloride-induced hepatotoxicity.

Acetaminophen↗
PubMed1992

Inhibition of acetaminophen hepatotoxicity by acetaldehyde in the rat.

Since we have observed that acetaldehyde, an oxidative metabolite of ethanol, inhibits acetaminophen activation in rat liver microsomes, the in vivo effect of acetaldehyde on acetaminophen hepatotoxicity was tested. In vivo experiments in 3-methylcholanthrene-pretreated male Sprague-Dawley rats showed that administration of cyanamide (20 mg/kg, i.p.) and acetaldehyde (600 mg/kg, s.c.) given 3 and 1 h, respectively, prior to acetaminophen (500 mg/kg, i.p.) but not cyanamide alone prevented acetaminophen hepatotoxicity as assessed by serum transaminases and histology. Acetaldehyde may partly be responsible for the inhibitory effect of ethanol on acetaminophen hepatotoxicity.

Acetaldehyde↗
PubMed1992

Effects of caffeine on paracetamol activation in rat and mouse liver microsomes.

1. The effects of caffeine on the NADPH-dependent production of paracetamol-glutathione conjugate were studied in rat and mouse liver microsomes. 2. In the presence of caffeine, glutathione conjugate production in rat microsomes was enhanced, whereas that in mouse microsomes was not affected significantly, showing an apparent species difference. 3. The data partly explain the species difference in the effects of caffeine on paracetamol hepatotoxicity.

Acetaminophen↗
PubMed1990

Influence of hormones on proliferation of ER-positive cells and ER-negative cells of human breast cancer (MCF-7).

The influence of endocrine therapy on the proliferation of estrogen receptor (ER)-positive cells and ER-negative cells of human breast cancer (MFC-7) serially transplanted into nude mice was analyzed by tumor growth, dextran-coated charcoal (DCC) method, ER-immunocytochemical assay (ER-ICA) and ER-immunocytochemically stained 3H-thymidine autoradiography. In the tamoxifen (TAM) group and the medroxyprogesterone acetate (MPA) group, tumor growth was inhibited, but it was promoted in the 17-beta-estradiol dipropionate (E2) group. The ER level by the DCC method was significantly decreased in the TMA, the MPA and the E2 groups. The ER-ICA showed that the percentage of ER-positive cells was decreased in the TAM and the MPA group, but it was increased in E2 group. However, the ER-immunocytochemically stained 3H-thymidine autoradiography showed that not only the labelling index of ER-positive cells but also that of ER-negative cells was significantly decreased in the TAM and the MPA groups, while the labelling index was significantly increased in the E2 groups. Therefore, it was concluded that endocrine therapy affected the proliferation of both ER-positive cells and ER-negative cells of ER-positive breast cancer.

Animals↗
PubMed1989

The significance of regional lymph node dissection in the surgical management of breast cancer.

The results of an analysis done on the regional lymph node metastases of 300 patients with operable breast cancer, who were treated in the Department of Surgery (II), Kanazawa University Hospital from 1973 to early 1988 are reported herein. It was found that the metastases of the axillary and internal mammary lymph nodes were closely related to the survival of patients, but they were hardly diagnosed before the operation. Only the dissection of these lymph nodes proved useful for providing the prognostic information. Moreover, in a retrospective study comparing the en bloc extended radical mastectomy versus the other types of mastectomy, the extended radical mastectomy was seen to greatly improve the survival of patients with 3 or less than 3 metastatic axillary lymph nodes. Thus, the extended radical mastectomy provides the maximum diagnostic and prognostic information, and gives the best chance of loco-regional control of the disease. The anterior chest deformity created by the extended radical mastectomy, however, should be avoided in those patients without internal mammary involvement. We therefore propose the modified extended mastectomy as a staging operation.

Adult↗
PubMed1989

Effects of nonsteroidal antiinflammatory drugs on collagen biosynthesis of cultured chondrocytes.

In conclusion, the data obtained from the present study show that TA has less effect than indomethacin or ASA on cultured chondrocytes in gene expression and synthesis of collagen. These findings cannot be directly interpolated to clinical application, but attention to pharmacologic activities of NSAIDs on chondrocytes may have future applications. Two major NSAIDs, TA, indomethacin, and ASA, were examined for their effects on the biosynthesis and gene expression of articular cartilage collagen. The biosynthesis of type II collagen was suppressed to 70% to 80% of the control by indomethacin and ASA. TA did not suppress collagen synthesis. To know the gene expression of type II collagen, dot blot hybridization was performed using type II collagen cDNA. The effects of NSAIDs on the amount of type II collagen mRNA were consistent with those on collagen biosynthesis. Thus, TA had the least effect on cultured chondrocytes.

Animals↗
PubMed1989

[Influence of endocrine therapy on the proliferation of estrogen (ER) positive cells and ER negative cells of human breast cancer (MCF-7)].

The influence of endocrine therapy on the proliferation of estrogen receptor (ER) positive cells and ER negative cells of human breast cancer (MCF-7) serially transplanted into nude mice was analyzed by tumor growth, dextran-coated charcoal (DCC) method, ER-immunocytochemical assay (ER-ICA) and ER-immunocytochemically stained 3H-thymidine autoradiography. In the tamoxifen (TAM) group and the medroxyprogesterone acetate (MPA) group, tumor growth was inhibited, but it was promoted in the 17 beta-estradiol dipropionate (E2) group. The ER level by the DCC method significantly decreased in the TMA, the MPA and the E2 groups. The ER-ICA showed that the ER positive cells rate in the TAM and the MPA group decreased, but it increased in E2 group. However, the ER-immunocytochemically stained 3H-thymidine autoradiography showed that not only the labelling index of ER-positive cells but also that of ER negative cells significantly decreased in the TAM and the MPA groups, but significantly increased in the E2 groups. Therefore it was concluded that endocrine therapy affected the proliferation of both ER positive cells and ER negative cells of ER positive breast cancer.

Animals↗