Biomedical subjects

T Tsujinaka

Publications and source records attributed to T Tsujinaka.

At least 55 records · Page 3Linked to original sources

PubMed1997

CYP1A1, CYP2E1 and GSTM1 polymorphisms are not associated with susceptibility to squamous-cell carcinoma of the esophagus.

We investigated the genetic polymorphisms of CYP1A1, CYP2E1 and GSTM1 in Japanese esophageal cancer patients (n = 53) with a histological diagnosis of squamous-cell carcinoma, to determine whether susceptibility to esophageal cancer is associated with these polymorphisms. There were no significant differences in the frequency distribution of any one of the 3 polymorphisms between esophageal cancer patients and 132 healthy Japanese controls. The genotype distributions in tobacco smokers or alcohol drinkers were also quite similar for male patients and male controls. The age at onset of esophageal cancer was also similar for patients with any genotype of the 3 polymorphisms. We conclude that the 3 polymorphisms are unlikely to be associated with esophageal cancer susceptibility.

Adult↗

PubMed1997

Role of supplementation of a nucleic acid solution on the intestinal mucosa under total parenteral nutrition.

Since dietary nucleotides play an important role in the growth and development of the intestine, supplementation of a nucleic acid solution (OG-VI) may support the optimal growth and integrity of the intestine under total parenteral nutrition (TPN). Supplementation of OG-VI to a TPN solution improved mucosal morphologic and functional changes, increased mucosal proliferation, and decreased mucosal permeability of the intestine. After 80% small bowel resection, OG-VI supplementation to a TPN solution attenuated the initial mucosal atrophy and improved intestinal cell turnover. Nucleic acid supplementation may be clinically beneficial in certain situations.

Animals↗

PubMed1997

Modulation of circadian expression of D-site binding protein by the schedule of parenteral nutrition in rat liver.

The aim of this study was to investigate the changes in the circadian rhythm of the expression of liver-specific genes caused by different schedules of parenteral nutrition (PN). Rats received PN continuously throughout the day or intermittently during the night or day for 7 days. They were examined for gene expression of D-site binding protein (DBP), albumin, and cytochrome P450 cholesterol 7alpha-hydroxylase (CYP7) in the liver. The nocturnal PN group showed circadian expression of DBP messenger RNA (mRNA) and protein with a peak at 10 PM, in the same manner as the control rats receiving normal chow feeding. However, the diurnal PN group showed inverted expression of DBP mRNA and protein with a peak at 10 AM. CYP7 mRNA levels exhibited good synchronization with the levels of DBP mRNA in all groups, whereas albumin mRNA levels did not show such synchronization. Gel mobility-shift assay disclosed that the binding activity of the nuclear extracts to the CYP7 gene promoter was changed by the PN schedule in accordance with the expression of CYP7 mRNA. The PN schedule modulates the circadian rhythm of DBP expression and may have an effect on hepatic bile acid formation through transcriptional regulation of the CYP7 gene.

Albumins↗

PubMed1997

Effects of cyclic and continuous parenteral nutrition on albumin gene transcription in rat liver.

To evaluate schedule-dependent effects of parenteral nutrition on albumin gene expression and regulation, mRNA levels for albumin and its promoter-binding nuclear factors in the liver were measured in rats receiving cyclic or continuous parenteral nutrition. Rats were divided into three groups: the control group (n = 5) received a nonpurified diet, the continuous parenteral nutrition group (n = 5) received a continuous infusion of a defined parenteral nutrition formula, and the cyclic parenteral nutrition group (n = 5) received a cyclic (between 2000 and 0800) infusion of the same formula. After 7 d, rats were killed to obtain serum and liver. The serum albumin concentrations were 44 +/- 3 g/L in the controls, 31 +/- 2 g/L in the continuous parenteral nutrition group, and 33 +/- 3 g/L in the cyclic parenteral nutrition group. The mRNA for albumin and D site binding protein (DBP) was more abundant and mRNA for CCAAT/enhancer binding protein beta (C/EBP beta) was less abundant in the cyclic parenteral nutrition group than in the continuous parenteral nutrition group. Gel-shift assay for D site and gel-shift Western blotting of DBP carried out using another three rats in each group revealed an increase of DBP in rats receiving cyclic parenteral nutrition compared with continuous parenteral nutrition. In conclusion, although parenteral nutrition decreases serum albumin concentrations, cyclic parenteral nutrition maintains transcription of the albumin gene to a greater extent than does continuous parenteral nutrition. Cyclic parenteral nutrition, in contrast with continuous parenteral nutrition, sustains the mRNA and concentrations of DBP.

Albumins↗

PubMed1997

Gene expression of albumin and liver-specific nuclear transcription factors in liver of protein-deprived rats.

Protein-energy malnutrition causes hypoalbuminemia. Recent work has suggested that this may be partly due to decreased transcription of the albumin gene. This study examined the role of cis-acting and transacting elements of the albumin gene during protein deprivation. Male 7-wk-old Donryu rats were fed a protein-free diet (0% casein diet) for 10 d or given restricted (pair-fed control) or free access (freely fed control) to a 25% casein diet. Serum albumin concentrations were significantly lower in the protein-deprived rats (29 +/- 1 g/L) than in the pair-fed controls (42 +/- 3 g/L) or the freely fed controls (45 +/- 3 g/L). The albumin mRNA level was also significantly lower in livers of protein-deprived rats (36% of pair-fed control). However, gel mobility shift analysis using liver nuclear extracts did not show any significant difference between the protein-deprived rats and the pair-fed controls in the binding activity to the B and D sites of the albumin promoter. Furthermore, gel mobility shift-Western blot analysis showed no significant difference between the two groups in the protein levels of nuclear transcription factors binding to the D sites. The amounts of mRNA of hepatocyte nuclear factor-1 binding to the B site were not significantly different between these two groups. These results suggest that the proximal promoter region may not play a major role in the down-regulation of the albumin gene during protein deprivation.

Analysis of Variance↗

PubMed1997

Involvement of interleukin-6 in activation of lysosomal cathepsin and atrophy of muscle fibers induced by intramuscular injection of turpentine oil in mice.

Serum IL-6 level increased after the injection of turpentine oil into the right gastrocnemius muscle in mice. The mRNA level of IL-6 was highest in the injected muscle at 12 h after injection, but was not identified in the opposite muscle. The activities of cathepsins B and B+L started to elevate after 12 h in the injected muscle and markedly increased after day 3. Likewise, the mRNA levels of cathepsins B and L markedly increased from day 1 to day 5 in the injected muscle. However, a very mild increase was also observed in the opposite muscle. Immunohistochemical staining of cathepsins B and L exhibited positive reactions as fine granules in myofibers at 12 h and strong positive reactions in the infiltrating macrophages at 3 days. Atrophy of myofibers type 1 and 2 was evident in a time-dependent manner in the injected muscle. Treatment with rat anti-mouse IL-6 receptor monoclonal antibody inhibited the increase in cathepsin activities in the injected muscle. We conclude that IL-6 produced in the inflamed muscle is involved in the process of muscle degeneration, especially through the activation of lysosomal cathepsins.

Animals↗

PubMed1997

[Preoperative synchronized chemoradiation therapy for advanced esophageal cancer].

Synchronized chemoradiation, where 5-FU and CDDP were synchronously administered in the same schedule with radiation therapy, was applied for advanced esophageal cancer in neoadjuvant fashion. Ten patients with advanced esophageal cancer were enrolled for this regimen consisting of 5-FU; 500 mg/day x 5/w x 4, CDDP; 10 mg/day x 5/w x 4 and radiation; 2 Gy x 5/w x 4. Tumor regression was achieved in all cases. In terms of toxicity, bone marrow suppression of more than grade 3 was observed in 60% of the cases, though it was safely controlled. Radical operation was performed on 8 cases. Histological responses in the resected specimen were as following: grade 3, 3 cases; grade 2b, 4 cases; grade 2a, 1 case; and 6 node-negative cases were found. As a postoperative complication, minor leakage occurred in 62.5%, while no major complications such as pneumonia were encountered. This neoadjuvant synchronized chemoradiation improved curability of the salvage operation and permitted reduction surgery for high-risk patients.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1997

[Local control of hepatic malignant tumors by percutaneous microwave].

We investigated the effects of percutaneous microwave coagulation under general anesthesia in the local control of hepatic malignant tumors. Coagulation at 60 W was done for normal liver of living swine using a percutaneous electrode. Wide-range coagulation at the tip of an electrode, 3 mm in diameter, was conducted. Clinically, echo-guided percutaneous microwave tumor coagulation was done for a total of 11 lesions in 5 patients with hepatocellular carcinoma and 4 with metastatic tumors in the liver under general anesthesia. Coagulation at 60 W of the liver of living swine for 1.5 and 10 min, using a percutaneous electrode, produced a maximal coagulation of 10, 20 and 30 mm, respectively. The trial electrode permitted coagulation almost at the tip of the electrode only. Percutaneous microwave coagulation of 11 lesions of the clinical cases resulted in complete coagulation in 7 lesions and incomplete coagulation in 4. The lesions showing complete coagulation were all less than 23 mm.

Animals↗

PubMed1997

[Preoperative chemoradiation therapy for advanced rectal cancer].

Preoperative concurrent chemoradiation therapy with 5-fluorouracil and cisplatin was applied for advanced rectal cancer. Eligible criteria were as follows: no previous treatment, 4 more than hemicircular occupation, T3 or more invasion to adjacent organs or lymph node metastasis on CT scan, tumor fixation by digital examination. Eleven patients were enrolled with this regimen consisting of 5-FU; 500mg/day x5/w x4, CDDP; 10mg/day X 5/w x4 and radiation; 2Gy x 5/w x 4. As a toxicity, grade 2 leukopenia in 2 cases, grade 2 GI symptoms in one case and radiation dermatitis was observed in 8 cases. As a local response, there were PR in 10 cases and NC in 1 case. Surgical resection was performed on 8 patients. Histological responses in the resected specimens were grade 2, 5 cases; grade 1b, 1 case; and grade la, 2 cases. Operative radicalities were grade A, 3 cases; grade B, 3 cases; and grade C, 2 cases. Preoperative chemoradiation is one of the effective options in multimodal treatment for advanced rectal cancer.

Adenocarcinoma↗

PubMed1996

Anti-interleukin-6 receptor antibody prevents muscle atrophy in colon-26 adenocarcinoma-bearing mice with modulation of lysosomal and ATP-ubiquitin-dependent proteolytic pathways.

Progression of skeletal muscle atrophy is one of the characteristic features in cancer patients. Interleukin-6 (IL-6) has been reported to be responsible for the loss of lean body mass during cancer cachexia in colon-26 adenocarcinoma (C-26)-bearing mice. This study was carried out to elucidate the intracellular proteolytic pathways operating in skeletal muscle in C-26-bearing mice, and to examine the effect of anti IL-6 receptor antibody on muscle atrophy. On day 17 after tumor inoculation, the gastrocnemius muscle weight of C-26-bearing mice had significantly decreased to 69% of that of the pair-fed control mice. This weight loss occurred in association with increases in the mRNA levels of cathepsins B and L, poly-ubiquitin (Ub) and the subunits of proteasomes in the muscles. Furthermore, enzymatic activity of cathepsin B+L in the muscles also increased to 119% of the control. The administration of anti-murine IL-6 receptor antibody to C-26-bearing mice reduced the weight loss of the gastrocnemius muscles to 84% of that of the control mice, whose enzymatic activity of cathepsin B+L and mRNA levels of cathepsin L and poly-Ub were significantly suppressed compared with those of the C-26-bearing mice. Our data indicate that both the lysosomal cathepsin pathway and the ATP-dependent proteolytic pathway might be involved in the muscle atrophy of C-26-bearing mice. The results also suggest that anti IL-6 receptor antibody could be a potential therapeutic agent against muscle atrophy in cancer cachexia by inhibiting these proteolytic systems.

Adenocarcinoma↗

PubMed1996

Temperature-dependent enhancement of proteolysis in C2C12 myotubes in association with the activation of 26S proteasome.

The effect of temperature on protein metabolism of C2C12 myotubes was investigated in order to estimate the potential effect of fever on muscle catabolism. The half-life of long-lived proteins in C2C12 myotubes was significantly (13%) shorter when incubated at 40 degrees C than at 37 degrees. The activities of cathepsins B and L were not significantly different at 37 and 40 degrees C, nor were the levels of the protein and mRNA of the two cathepsins. In contrast, the chymotrypsin-like activity of 26S proteasome was elevated by 53% at 40 degrees C, compared to that at 37 degrees C, although it was not associated with an increase in the levels of the protein and mRNA of proteasome subunits. mRNA levels of calpain and ubiquitin were not affected by temperature. It is concluded that temperature-dependent enhancement of proteolysis in C2C12 myotubes is associated with an increase in 26S proteasome activity.

Animals↗

PubMed1996

Interleukin 6 receptor antibody inhibits muscle atrophy and modulates proteolytic systems in interleukin 6 transgenic mice.

The muscles of IL-6 transgenic mice suffer from atrophy. Experiments were carried out on these transgenic mice to elucidate activation of proteolytic systems in the gastrocnemius muscles and blockage of this activation by treatment with the anti-mouse IL-6 receptor (mIL-6R) antibody. Muscle atrophy observed in 16-wk-old transgenic mice was completely blocked by treatment with the mIL-6R antibody. In association with muscle atrophy, enzymatic activities and mRNA levels of cathepsins (B and L) and mRNA levels of ubiquitins (poly- and mono-ubiquitins) increased, whereas the mRNA level of muscle-specific calpain (calpain 3) decreased. All these changes were completely eliminated by treatment with the mIL-6R antibody. This IL-6 receptor antibody could, therefore, be effective against muscle wasting in sepsis and cancer cachexia, where IL-6 plays an important role.

Animals↗

PubMed1996

Modulation of thermogenic response to parenteral amino acid infusion in surgical stress.

Thermogenic response to parenteral infusion of amino acid mixtures in rats undergoing surgical stress was investigated with the aid of a small animal indirect calorimeter. Male Wistar rats (n = 12) were laparotomized and received intestinal abrasion along with construction of a parenteral route. After 48 h, nutrient-induced thermogenesis (NIT) produced by amino acid mixtures was examined and compared with that of control rats (n = 12) without surgical stress. The NIT values of the leucine-enriched solution were greater than those of the control solution in both rats with and without surgical stress. The NIT generated by the leucine-enriched solution in rats with surgical stress was significantly higher than that in rats without. NIT values for 10 different kinds of single amino acid solutions with identical concentrations was then examined in 60 rats. The NIT values of the leucine and the glycine solutions were relatively higher than those of other solutions. However, when puromycin was injected intraperitoneally into 12 rats just before measurement of the NIT in response to amino acid mixtures, no significant differences were found in NIT values between the mixtures. In summary, surgical stress increased the thermogenic response to the leucine-enriched solution, indicating that utilization of leucine may be augmented under surgical stress. In fact, leucine itself may be a thermogenic amino acid. Inhibition of protein synthesis prevented the increase in thermogenic response induced by the leucine-enriched solution. We conclude that thermogenic responses to parenteral amino acid mixtures may differ depending not only upon the compositions of amino acids but also upon the host conditions.

Amino Acids↗

PubMed1996

A total parenteral nutrition solution supplemented with a nucleoside and nucleotide mixture sustains intestinal integrity, but does not stimulate intestinal function after massive bowel resection in rats.

The effects of supplementing a total parenteral nutrition solution with a nucleoside and nucleotide mixture on mucosal adaptive processes after massive bowel resection were studied. Male Wistar rats (n=30) underwent 80% small intestine resection, were randomized into two groups and received either standard total parenteral nutrition (TPN) or TPN supplemented with a nucleoside and nucleotide mixture (2.5 mL.kg-1.d-1). An additional five rats, fed a nonpurified diet and not resected, were used as controls. After 4 or 7 d, rats were killed and samples were collected for mucosal indices and intestinal enzymatic activities (disaccharidases and diamine oxidase). After massive small bowel resection and TPN, residual jejunal mucosal wet weights, villus heights, protein and RNA contents on d 4 and 7, and total wet weights and DNA contents on d 7 were significantly lower than in the control group. Administration of the nucleoside and nucleotide mixture resulted in significantly higher residual jejunal total and mucosal weights, proteins, DNA, RNA contents, and the ratio of proliferating cell nuclear antigen positive cells per crypt than did the standard TPN solution on d 7. However, disaccharidase and diamine oxidase activities were not affected by supplementation with the nucleoside and nucleotide mixture. Our data suggest the supplementation of a nucleoside and nucleotide mixture to a TPN solution can attenuate the initial mucosal atrophy and improve intestinal cell turnover after massive bowel resection, but the supplementation has little effect on enterocyte enzymatic activities.

Amine Oxidase (Copper-Containing)↗

PubMed1996

Role of interleukin-6 in skeletal muscle protein breakdown and cathepsin activity in vivo.

In order to elucidate the acute and chronic effects of interleukin-6 (IL-6) on muscle protein degradation, the weight of skeletal muscles and the activities of lysosomal cathepsins (B and L) in the muscles were examined in two animal models. Two intraperitoneal injections of recombinant human IL-6 into rats did neither significantly affect the cathepsin activities in the soleus and the extensor digitorum longus muscles nor the weight of these muscles. On the other hand, the gastrocnemius muscles of the IL-6 transgenic mice underwent severe atrophy accompanied by a marked increase in cathepsin activities. We conclude that IL-6 mediates muscle protein degradation with enhancing lysosomal cathepsin activity, and that these muscle reactions are mandated by chronic exposure to a high level of IL-6.

Animals↗

PubMed1996

[Preoperative chemoradiation therapy for lower rectal cancer].

To identify appropriate candidates with rectal cancer for preoperative chemoradiation therapy, the local recurrence rate and clinicopathological characteristics of 232 patients with rectal cancer undergoing curative resection in our department were investigated. The local recurrence rates were 3.8%, 10.8% and 16.5% in the Rs, Ra and Rb lesions, respectively. Regarding lower (Rb) rectal cancer, depth of lesion (> a1) and nodal metastasis consisted of high factors for local recurrence. Basing on these results, entry criteria for preoperative chemoradiation therapy were established, and concurrent chemoradiation therapy with fluorouracil and cisplatin was delivered preoperatively in 9 primary cases of locally advanced rectal cancer and 3 cases with local recurrence. A partial response was obtained in 7 of 12 cases with a response rate of 58%, size-reduction of the distant metastatic lesions was found in 2 cases, and clinical symptoms were improved in all cases. The histological responses of the 6 resected cases were Grade 2 in 2 cases and Grade 1b in 4 cases. The toxicities of this chemoradiation regimen were well tolerable. As a postoperative complication, infection of the perineal wound was most frequent. Preoperative chemoradiation therapy with the present regimen would be a useful adjuvant treatment for advanced lower rectal cancer.

Aged↗

PubMed1996

[Evaluation of percutaneous microwave hepatic tumor coagulation therapy (PMTC) under general anesthesia from viewpoint of quality of life (QOL)].

We evaluated clinical benefits (QOL and local control rate) of percutaneous microwave coagulation therapy conducted with general anesthesia. Five cases with hepatic tumor (3 cases with hepatocellular carcinoma, 2 cases with metastatic hepatic tumor) were enrolled. The day following treatment all patients were virtually free of complaints with performance status ranging 0 to 1, and they were discharged from the hospital within 1 week. Four of five cases could be controlled solely with this treatment: one case showed local relapse, the tumor size of which exceeded 3 cm. PMTC may be one of the most beneficial local treatments for malignant hepatic tumor, since it shortens hospital stay with a good QOL status, and is applicable to metastatic tumor.

Aged↗

PubMed1995

Autocatalytic inactivation of lysosomal cathepsins is associated with inhibition of protein breakdown by insulin-like growth factor-1 (IGF-1) in myotubes.

Protein breakdown was monitored in C2C12 myotubes as the rate of release of radioactivity after prelabeling cell protein with [3H] tyrosine. IGF-1 (13 nM) and insulin (100 nM) prolonged the half-life of long-lived proteins. Enzymatic activities of cathepsins B and B+L were inhibited by the addition of IGF-1 or insulin. Immunoblotting of cathepsins B and L revealed extensive degradation of heavy chain forms by IGF-1. However, neither expression of cathepsins B and L genes nor expression of cystatin beta, an intrinsic inhibitor for cathepsins, was influenced. The addition of E-64, L-3-carboxy-trans-2,3-epoxypropionyl-leucylamide-(4-guanidin o) butane, a inhibitor of cathepsins B and L, increased protein contents of heavy chains of cathepsins B and L in the IGF-1 treated cells. Inhibition of protein breakdown by IGF-1 is mediated by autocatalytic inactivation of lysosomal cathepsins B and L.

Analysis of Variance↗