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Biomedical subjects

T Tsujino

Publications and source records attributed to T Tsujino.

At least 19 recordsLinked to original sources

Expression of PPARdelta in multistage carcinogenesis of the colorectum: implications of malignant cancer morphology.

Whether peroxisome proliferator-activated receptor (PPAR) delta is a good target for the chemoprevention and/or treatment of colorectal cancer (CRC) remains controversial. Our goal was to examine PPARdelta expression in multistage carcinogenesis of the colorectum and to assess the relevance of PPARdelta in CRC. Immunohistochemical analysis indicated that PPARdelta expression increased from normal mucosa to adenomatous polyps to CRC. In cancer tissues, the PPARdelta protein was accumulated only in those cancer cells with highly malignant morphology, as represented by a large-sized nucleus, round-shaped nucleus, and presence of clear nucleoli. Interestingly, the cancer tissue often contained both PPARdelta-positive and -negative areas, each retaining their respective specific morphological features. Moreover, this pattern persisted even when PPARdelta-positive and -negative cells were aligned next to each other within a single cancer nest or gland and was present in the majority of CRC cases. Immunohistochemistry for Ki-67 proliferation marker showed no significant correlation between Ki-67 and PPARdelta in CRC samples. Based on Western blot analysis and quantitative RT-PCR, high PPARdelta protein expression correlated with high PPARdelta mRNA levels. Peroxisome proliferator-activated receptor delta may have a supporting role in tumorigenesis, and the close association between PPARdelta expression and malignant morphology of CRC cells suggests a pivotal role in cancer tissue.

Adenocarcinoma↗

High-rate pulmonary involvement in autoimmune pancreatitis.

Autoimmune pancreatitis (AIP) has extrapancreatic complications such as Sjögren's syndrome, retroperitoneal fibrosis and sclerosing cholangitis. We studied 30 patients with AIP. Of these, we identified pulmonary involvement in four patients during follow up. Among them, two patients had respiratory failure. They showed good response to steroid therapy, but a higher dose of prednisolone was necessary to maintain remission than that required in biliary involvement. Elevation of immunoglobulin G(4) and Krebs von den Lungen-6 levels were characteristic of pulmonary involvement. They may be useful for early detection of pulmonary complication.

Aged↗

Uterine bizarre epithelioid lipoleiomyoma with a myxoid stroma.

The first case of uterine bizarre epithelioid lipoleiomyoma with a myxoid component occurring in an 86-year-old woman is described. An intramural 22 cm mass in the anterior wall of the uterine body had a lipoma-like appearance with strands of fibrous tissue. Histologically, the tumor consisted of adipocytes which varied in size and shape, and epithelioid smooth muscle cells with nuclear atypia within a myxoid stroma. No mitotic features were noted despite an extensive search. The patient was well without disease 24 months after hysterectomy. Patients with this type of tumor need close and long-term follow-up because of the paucity of clinical information.

Aged, 80 and over↗

A prospective randomised study of "covered" versus "uncovered" diamond stents for the management of distal malignant biliary obstruction.

BACKGROUND AND AIM: Covered self-expandable metal stents (EMS) were recently developed to overcome tumour ingrowth in conventional EMS. However, supporting evidence for the efficacy of covered EMS is lacking. PATIENTS AND METHODS: We enrolled 112 patients with unresectable distal biliary malignancies. They were randomly assigned to polyurethane covered (n = 57) or original diamond stent (n = 55). RESULTS: Stent occlusion occurred in eight patients (14%) after a mean of 304 days in the covered group, and in 21 patients (38%) after a mean of 166 days in the uncovered group. The incidence of covered EMS occlusion was significantly lower than that of uncovered EMS (p = 0.0032). The cumulative stent patency of covered stents was significantly higher than that of uncovered stents (p = 0.0066). No tumour ingrowth occurred in the covered group while it was observed in 15 patients in the uncovered group. In subgroup analysis, the cumulative patency of the covered EMS was significantly higher in pancreatic cancer (p = 0.0363) and metastatic lymph nodes (p = 0.0354). There was no significant difference in survival between the two groups. Acute cholecystitis was observed in two of the covered group and in none of the uncovered group. Mild pancreatitis occurred in five of the covered group and in one of the uncovered group. CONCLUSIONS: Covered diamond stents successfully prevented tumour ingrowth and were significantly superior to uncovered stents for the treatment of patients with distal malignant biliary obstruction. However, careful attention must be paid to complications specific to covered self-expandable metal stents, such as acute cholecystitis and pancreatitis.

Acute Disease↗

A phosphodiesterase inhibitor, cilostazol, prevents the onset of silent brain infarction in Japanese subjects with Type II diabetes.

AIMS/HYPOTHESIS: This study aimed to evaluate the effect of a phosphodiesterase inhibitor, cilostazol, on the prevention of silent brain infarction in diabetic patients without symptoms of vascular events. METHODS: A total of 89 subjects were allocated at random to the cilostazol group ( n = 43) or the control group ( n = 46). RESULTS: After the study period (3.2 +/- 0.5 years), carotid intima-media thickness (IMT) (means +/- SD) had increased ( p < 0.01) by 0.18 +/- 0.19 mm in the control group. In the cilostazol group, intima-media thickness showed almost no change (-0.00 +/- 0.16 mm). In the control group, 2 out of 46 subjects showed symptomatic brain infarctions and 10 out of 34 subjects without infarct-like region assessed by standard brain MRI examination showed silent brain infarctions after the observation period. On the other hand, no subjects in the cilostazol group showed silent brain infarction or strokes during the study period. Both at the beginning and end of the study period, the number of infarct-like regions positively correlated with IMT ( r = 0.335, p < 0.001 or r = 0.347, p < 0.001 respectively). The progression of infarct-like regions was directly related to the increase in IMT during the study period ( r = 0.299, p = 0.004). CONCLUSION/INTERPRETATION: These data demonstrated that cilostazol could prevent the onset of silent brain infarction in Japanese subjects with Type II (non-insulin-dependent) diabetes mellitus. Also, an increase in intima-media thickness of the carotid artery wall could be able to predict the onset of silent brain infarction.

Aged↗

A case of aceruloplasminaemia: abnormal serum ceruloplasmin protein without ferroxidase activity.

A 34 year old diabetic man with a complete deficiency of serum ferroxidase activity, regardless of the presence of serum ceruloplasmin (Cp), a multicopper ferroxidase protein, is described. The patient had had diabetes mellitus for 13 years, and was also found to have retinal degeneration accompanied by the development of a hearing disturbance of unknown aetiology. Laboratory examination showed markedly increased serum ferritin and low serum iron. Magnetic resonance imaging showed a pronounced hypointensity in the putamen, caudate, cerebellar dentate, and thalamus on T2 weighted images, and also disclosed a low level signal in the liver, suggesting the accumulation of some magnetic substances in the brain and liver. Liver biopsies histochemically identified iron deposition in the hepatocytes. Most of these findings were consistent with the newly established autosomal recessive disease "aceruloplasminaemia", except for the presence of serum Cp and the lack of apparent neurological symptoms. Interestingly, no ferroxidase activity was detected in the patient's serum, whereas suppressed ferroxidase activity was found in his mother's serum. A nucleotide sequence analysis of the Cp gene showed two mutations; a C to T substitution at nucleotide 2701 in exon 16, resulting in a nonsense mutation at amino acid 882 (Arg882ter), and a T to G substitution at nucleotide 2991 in exon 17, resulting in an amino acid alternation at amino acid 978 (His978Gln). The second mutation was also found in the patient's mother. The absence of serum ferroxidase activity despite the presence of serum Cp protein in this compound heterozygote was considered to be due to the production of a non-functional Cp harbouring no ferroxidase activity.

Adult↗

Enantiodivergent synthesis of either enantiomer of ABCDE-ring analogue of antitumor antibiotic fredericamycin A via intramolecular [4 + 2] cycloaddition approach.

[reaction: see text] An intramolecular enantiodivergent synthesis of both enantiomers of the ABCDE-ring analogue 22 of fredericamycin A is reported. Key steps involve an intramolecular [4 + 2] cycloaddition of 17 and an aromatic Pummerer-type reaction of 19. A lipase-catalyzed enantioselective desymmetrization of prochiral diol 2 using 1-ethoxyvinyl 2-furoate 3 led to the pivotal intermediate (R)-4.

Antibiotics, Antineoplastic↗

Taurine prevents the decrease in expression and secretion of extracellular superoxide dismutase induced by homocysteine: amelioration of homocysteine-induced endoplasmic reticulum stress by taurine.

BACKGROUND: Hyperhomocysteinemia is an independent risk factor for atherosclerosis. Homocysteine has been shown to induce endoplasmic reticulum (ER) stress in vascular endothelial cells. ER stress is a condition in which glycoprotein trafficking is disrupted and unfolded proteins accumulate in the ER. ER molecular chaperons, such as GRP78, are induced and an ER resident kinase, PERK, is activated when cells are subjected to ER stress. Conversely, taurine is reported to have antiatherogenic effects by unknown mechanisms. To elucidate the mechanisms by which homocysteine induces atherosclerosis and taurine prevents it, we examined whether homocysteine and taurine affect the expression and secretion of extracellular superoxide dismutase (EC-SOD), a glycoprotein secreted from vascular smooth muscle cells (VSMCs) that protects the vascular wall from oxidative stress. METHODS AND RESULTS: We assessed the expression of EC-SOD and GRP78 mRNA in cultured rat VSMCs by Northern blot analysis. The EC-SOD protein secreted into the culture medium was examined by Western blot analysis. Homocysteine (5 mmol/L) and other ER stress inducers, including A23187, were found to decrease EC-SOD mRNA expression and protein secretion. Furthermore, they upregulated GRP78 mRNA expression and activated PERK. Taurine (0.5 to 10 mmol/L), conversely, prevented these actions induced by homocysteine. CONCLUSIONS: Homocysteine induces ER stress and reduces the secretion and expression of EC-SOD in VSMCs, leading to increased oxidative stress in the vascular wall. Taurine restores the secretion and expression of EC-SOD by ameliorating ER stress induced by homocysteine.

Animals↗

Effects of eicosapentaenoic acid on blood pressure, cell membrane fatty acids, and intracellular sodium concentration in essential hypertension.

This study was designed to clarify the effects of orally administered eicosapentaenoic acid (EPA) on blood pressure, intracellular sodium content, and cell membrane fatty acid composition in patients with essential hypertension. After a 4-week run-in period, a study group of 17 male patients was assigned to an 8-week treatment with EPA (2.7 g/day) or placebo in a randomized, double-blind fashion with a crossover at week 4. Systolic blood pressure (SBP) was lower after treatment with EPA than after treatment with placebo (152.9+/-17.3 vs. 162.6+/-20.6 mmHg; p<0.01), while diastolic blood pressure was not statistically different. Compared with the placebo treatment, EPA supplementation resulted in a decrease in intraerythrocyte sodium content (R-Na; 11.17+/-0.63 vs. 10.44+/-1.28 nmol/l cells; p<0.05) accompanied by an increase (p<0.001) in erythrocyte membrane EPA content. The increase in membrane EPA content was related to the decrease in SBP (r=-0.52, p<0.05) and the decrease in R-Na (r=-0.57, p<0.02) during EPA treatment. The decrease in R-Na correlated positively with the decrease in SBP (r=0.54, p<0.05), and correlated negatively with the change in Na+-K+ ATPase activity (r= -0.59, p<0.02). However, the change in Na+-K+ ATPase activity did not directly correlate with the change in membrane EPA content. In conclusion, oral EPA supplementation increased membrane EPA content and reduced SBP in patients with essential hypertension. Based on the association between the increase in membrane EPA content and the decrease in intracellular sodium concentration, EPA may lower blood pressure by altering the activities of the membrane sodium transport systems.

Adult↗

Total synthesis of the antitumor antibiotic (+/-)-fredericamycin A by a linear approach.

A linear approach to the total synthesis of racemic fredericamycin A (1) through the oxidative intramolecular [4 + 2] cycloaddition of a (phenylthio)acetylene-cobalt complex is described, which is applicable for the asymmetric total synthesis of naturally occuring 1. The highlight of this work is the aromatic Pummerer-type reaction with 1-ethoxyvinyl chloroacetate, which effects the introduction of the oxygen functional group to the internal B-ring of the highly functionalized, congested polyaromatic ABC-ring moiety.

Antibiotics, Antineoplastic↗

Evaluation of gut motility in type II diabetes by the radiopaque marker method.

BACKGROUND: The clinical usefulness of the radiopaque marker method for detecting diabetic gastrointestinal motility disturbances, was evaluated by examining 21 type II diabetes subjects who did not have any neuropathic symptoms. METHODS: After administration of a Sitzmark capsule, markers were located using plain abdominal radiographs, and the transit time of the markers through seven areas of digestive tract was calculated by Arhan's methods. The plasma concentration of acetaminophen at 45 min after oral administration was measured to evaluate gastric emptying time. The coefficient of variation of R-R intervals on the electrocardiograms (CV(R-R)) was measured to evaluate parasympathetic autonomic function. RESULTS: In the diabetics, the average (+/- SD) transit time through upper digestive tracts was slightly but not significantly elongated compared with control subjects (14.4 +/- 8.3 vs 9.9 +/- 6.1 h). Significant elongation was observed in transit time through the lower digestive tracts or the whole gut (44.6 +/- 20.9 and 57.9 +/- 22.3 h, respectively) compared with control subjects (23.3 +/- 8.5 and 33.2 +/- 11.0 h). The transit time of the markers from stomach to small intestine was highly correlated (r = 0.693) with plasma concentration of acetaminophen. The transit time through either the whole colon (r = 0.564) or the whole gut (r = 0.630) was highly correlated with CV(R-R). CONCLUSIONS: These findings suggest that the radiopaque marker method is a useful tool for detecting the sections of the digestive tract responsible for gut motility disturbances. In type II diabetics with no neuropathic symptoms, the lower digestive tracts may deteriorate prior to the impairment of upper digestive tracts.

Acetaminophen↗

Oral taurine supplementation prevents the development of ethanol-induced hypertension in rats.

Taurine is known to lower blood pressure in essential hypertension and some experimental hypertensive models. Taurine has also been reported to activate aldehyde dehydrogenase and to inhibit the elevation of plasma acetaldehyde concentration after ethanol intake. Because acetaldehyde, the first metabolite of ethanol, is suspected to be responsible for many adverse effects of alcohol consumption, we examined the effect of taurine supplementation on ethanol-induced hypertension and abnormalities in the intracellular cation metabolism in Witar-Kyoto rats. In Study 1, systolic blood pressure and intraplatelet free calcium were significantly higher in rats who received 15% ethanol in drinking water than in control rats. Oral taurine supplementation (1% taurine and 15% ethanol in drinking water) completely prevented the development of ethanol-induced hypertension. Intraerythrocyte sodium and intraplatelet free calcium were significantly decreased in taurine-supplemented rats as compared with rats who received 15% ethanol only. In Study 2, hemoglobin-associated acetaldehyde (HbAA) was measured as a marker of protein-bound acetaldehyde. HbAA was significantly elevated in rats who received 5% ethanol in drinking water as compared with control rats. Taurine supplementation (1% taurine and 5% ethanol in drinking water) significantly decreased HbAA. Our findings suggest that the oral supplementation of taurine prevents ethanol-induced hypertension by decreasing protein bound acetaldehyde and altering the cation handling by the membrane.

Acetaldehyde↗

[Transaortic video-assisted thrombectomy in the left ventricular cavity after acute myocardial infarction].

In recent years much attention has been paid to a minimal invasive surgery even in the field of cardiac surgery. We have successfully treated a 59 year-old male who underwent transaortic video-assisted thrombectomy in the left ventricular cavity following acute myocardial infarction due to occlusion (No. 7) of the left descending coronary artery (LAD). After the LAD was recanalized by percutaneous transluminal coronary angioplasty (PTCA) and then stenting, this thrombectomy was carried out. Following initiation of cardiopulmonary support, thrombus in the left ventricular apex was safely removed by transaortic endoscopic guidance. This technique was useful especially for the patient with poor ventricular function due to acute myocardial infarction because of no left ventriculotomy. Endoscopic guidance technique is reported in detail.

Angioplasty, Balloon, Coronary↗

[Urological procedures for progressive renal dysfunction due to polycystic kidney disease].

Urological procedures for progressive renal dysfunction due to polycystic kidney disease (PKD) such as percutaneous puncture of renal cysts are merely symptomatic treatments and have little effect on renal function. At present, the two most effective methods of preventing renal dysfunction are blood pressure management and dietetic therapy, which are more effective with early initiation. Moreover, as PKD is an autosomal dominant disease, there is a high risk that family members of the patient may have asymptomatic PKD. It is essential to identify and treat such potential patients at an early stage in order to prevent progressive renal dysfunction. In place of the traditional nephrectomy, we attempted transcutaneous renal arterial embolization (TRAE) for hemorrhage into renal cysts, hematuria and obstruction of intestine due to proliferation of cysts after the introduction of hemodialysis. When TRAE was carried out on one kidney, the cysts in the other kidney proliferated and even though the renal arteries were completely embolized, it required 5 to 6 weeks for the kidney to contract. Our conclusions are TRAE is effective with no adverse reactions for PKD. These results suggest that in the future TRAE may become the preferred treatment for PKD in place of nephrectomy.

Embolization, Therapeutic↗

Washout of small stones in the bile duct by saline infusion using a side-holed balloon catheter in patients undergoing endoscopic papillary balloon dilation.

BACKGROUND: Complete bile duct clearance of stones should be achieved in patients managed with endoscopic papillary balloon dilation. However, complete retrieval of small stones or tiny fragments sometimes proves difficult using conventional devices. METHODS: We attempted the removal of fine stone fragments by saline infusion using a specially designed retrieval balloon catheter with a blind tip and a side hole located proximal to the balloon in 14 patients. RESULTS: Using this technique, bile duct clearance was achieved in a single attempt in 13 of 14 patients; 2 attempts were required in 1 patient. Cholecystitis occurred in 2 patients with gallstones in situ after the procedure. CONCLUSIONS: Saline washout using a side-holed retrieval balloon catheter effectively cleans stones and stone fragments from the bile duct in patients treated with endoscopic papillary balloon dilation.

Aged↗

Insulin resistance contributes to carotid arterial wall thickness in patients with non-insulin-dependent-diabetes mellitus.

The aim of this study was to clarify whether insulin resistance contributes to atherosclerosis in patients with non-insulin-dependent diabetes mellitus (NIDDM). Fifty-three NIDDM patients (36 males and 17 females, 53+/-10 years old (mean+/-SD)) were studied. As an index of atherosclerosis, we measured the average thickness (IMT) as well as basal thickness excluding the maximum thickness and the height of the maximum thickness of the carotid artery wall. Euglycemic hyperinsulinemic glucose clamp was conducted for 90 min to evaluate average glucose infusion rate (GIR) as an index of insulin sensitivity in the peripheral tissues. For another 180 min after intake of oral glucose load with 0.3 g/kg, the euglycemic hyperinsulinemic clamp was continued to measure ratio of splanchnic glucose uptake (SGU) as an index of insulin sensitivity of the liver. The patients were separated into three activity groups according to the grade of their leisure-time physical activity. GIR (r = -0.32, p < 0.05) but not SGU (r=0.139) showed a significant inverse relationship with IMT. Multivariant regression analysis indicated that age and total cholesterol remain as independent risk factors for basal thickness and GIR as only independent risk factor for the height of the maximum thickness. Paralleling the degrees of habitual exercise (low, moderate, and high active group), GIR was higher (6.19+/-1.02, 6.38+/-1.38, 7.44+/-1.80, respectively) and IMT was lower (1.34+/-0.33 mm, 1.20+/-0.31 mm, and 1.12+/-0.29 mm, respectively) in male NIDDM as well as in female NIDDM. These data suggest that insulin resistance in the peripheral tissues but not the splanchnic tissues may independently contribute to carotid arterial wall thickness and especially to plaque lesion, and that habitual exercise might reduce insulin resistance leading to attenuation of atherosclerosis.

Aged↗

A non-peptide compound which can mimic the effect of thrombopoietin via c-Mpl.

Thrombopoietin (TPO) is a cytokine which plays a central role in megakaryopoiesis and platelet production by binding to its cell surface receptor, termed c-Mpl. In the present study, two benzodiazepinones that compete with the binding of TPO to the extracellular region of c-Mpl were identified, and one of them stimulated the proliferation of a human TPO-dependent megakaryocytic cell line, UT-7/TPO. It stimulated the activation of signal transducer and activator of transcription 5 in UT-7/TPO cells. These results suggest that a non-peptide compound can mimic the effect of TPO via c-Mpl.

Benzodiazepinones↗