Search PubMed⌕ Search

Biomedical subjects

K Sugimachi

Publications and source records attributed to K Sugimachi.

At least 109 records · Page 6Linked to original sources

[Basic study about the development of the hybrid-artificial liver support system using human hepatoma cell lines (Hep G2, Huh 7): effects on liver functions by extracellular matrix (type I collagen) in monolayer culture].

The risk of xenozoonosis infections poses the greatest obstacles against the clinical application of hybrid-artificial liver support system (HALSS). To resolve this issue, we used human hepatoma cell lines (Hep G2, Huh 7) in a type I collagen-coated monolayer culture system, and analyzed liver specific functions such as ammonia removal and albumin synthesis capacity. Ammonia removal activity (nmol/10(6) nuclei/hour) and albumin synthesis activity (microgram/10(6) nuclei/day) were upregulated in both Hep G2 and Huh 7 by type I collagen-coated monolayer culture. In particular, Hep G2 cultured in type I collagen-coated monolayer demonstrated relatively high ammonia removal and albumin synthesis capacity. These results indicate the possibility of the application of human hepatocytes to HALSS.

Albumins↗

Nuclear expression of the Y-box binding protein, YB-1, as a novel marker of disease progression in non-small cell lung cancer.

Transcription factor Y-box binding protein 1 (YB-1) that binds to the inverted CCAAT box is involved not only in transcription of various genes but also in cell proliferation and DNA repair. We determined whether localization of YB-1 in either the nucleus or cytoplasm could serve as a prognostic marker for patients with non-small cell lung cancer (NSCLC). In 196 NSCLC patients, expression of YB-1 protein in the nucleus or cytoplasm was immunohistochemically evaluated. Of the 196 tumors examined, 88 (44.9%) were positive for YB-1 expression in the nucleus. Nuclear YB-1 expression significantly correlated with T factor, lymph node metastasis, and stage of the disease. Patients with a nuclear YB-1 tumor had a poorer prognosis than did those with a cytoplasmic YB-1 tumor in all of the NSCLC patients (P = 0.0494) and in patients with squamous cell carcinoma (P = 0.0313) but not in patients with adenocarcinomas. Nuclear localization of the YB-1 protein may prove to be an important factor of disease progression for patients with NSCLC, in particular, in cases of squamous cell carcinoma.

Adenocarcinoma↗

[Current status and future of surgical robotic systems].

In this review, we are commenting the current status and the future of surgical robotic systems. AESOP is a voice-controlled laparoscope manipulator that enables the "Solo-surgery". ZEUS is a master-slave manipulator that is characterized by its simplicity and lightness. da Vinci is another master-slave manipulator that has more range of freedom, therefore a surgeon can perform the operation with fewer difficulties. The technological development of high-quality and real-time 3D simulation, minimization of scopes and power saving techniques made these surgical robots realized. Although many pending matters such as lack of safety guideline or lack of accuracy of sensor/monitor have been raised in current surgical robotics, the development of the technologies may promise to resolve such matters in the future.

Forecasting↗

[Angiogenesis and macrophage infiltration in Borrmann type IV gastric cancer].

The clinical significance of angiogenesis was investigated in Borrmann type IV gastric cancer. Tumors with high microvessel density (MVD) often metastasized to the liver and lymph nodes. A significant correlation was recognized between macrophage infiltration and MVD. However, MVD was not a prognostic factor. Peritoneal dissemination was a prognostic factor in Borrmann type IV gastric cancer. Thus, angiogenesis plays an important role in the metastasis, but not prognosis in Borrmann type IV gastric cancer.

Aged↗

Development of colonic neoplasms and expressions of p53 and p21 proteins in experimental colitis of mice induced by dextran sulfate sodium.

The mechanisms underlying the frequent development of colorectal carcinomas in patients with ulcerative colitis (UC) are still not understood. This study was conducted to investigate whether p53 and p21 protein expressions contribute to carcinogenesis in an experimental model with dextran sulfate sodium (DSS) treatment, and to establish if this colitis model is suitable for study of cancer development in UC. A total of 40 mice were subjected to four administration cycles of 4% DSS for 7 days followed by plain water for the subsequent 14 days. The 33-surviving mice were sacrificed to examine the malignant transformation of colonic mucosa morphologically and to determine p53 and p21 expressions immunohistochemically. After DSS treatment periods, there were marked irregularities in the mucosal layer, the thickness of the entire bowel wall and the shortness of the colon. Histologically, tumors were found in 13 out of 33 (39.4%) mice. These 13 cases included 9 with a solitary lesion and 4 with double tumors. There were occurrences of invasive carcinomas in 8 lesions, high-grade dysplasia in 3 lesions and low-grade-dysplasia in 6 lesions. One presented with a polypoid tumor, 5 mm in diameter, while 16 had small flat lesions. There were 13 tumors on the left-sided colon, as opposed to 4 on the right-sided colon. Histological differentiation of invading carcinomas revealed that 6 out of 8 lesions were comprised of well differentiated adenocarcinomas, while 2 were moderately differentiated adenocarcinomas. Overexpression of p53 protein was found in 4 out of 8 invasive carcinomas, 2 out of 3 high-grade dysplasia cases and 2 out of 6 low-grade dysplasia cases, whereas only 1 out of 8 with invasive carcinoma was positive for p21. This experimental colitis model suggests that p53 and p21 protein expressions may contribute to carcinogenesis in DSS-induced colitis in mice and appears suitable to study cancer development in UC.

Animals↗

Asymptomatic atresia of the lobar bronchus of the lung: a case report.

A 64-year old woman presented with an asymptomatic occlusion of the intermediate bronchus associated with a peripheral mass occupying the entire middle and lower lobes. As malignancy was suspected, inferior bilobectomy was done. There was a complete atelectasis of both lobes, with massive parenchymal necrosis. Pathological examinations suggested a tuberculous granuloma in the bronchus and parenchyma although tuberculous bacilli were not found. This case was unusual as congenital anomaly, and was suspected as bronchial tuberculosis.

Bronchi↗

Mass preparation of primary porcine hepatocytes and the design of a hybrid artificial liver module using spheroid culture for a clinical trial.

To isolate a large number of porcine hepatocytes, we originally developed a mass preparation method that combined the usual collagenase perfusion method of a whole liver with a collagenase redigestion method of tissue fragments after liver perfusion. Using a pig of 10kg, collagenase perfusion only resulted in a yield of 63+/-78 x 10(8) total cells with a viability of 69.2+/-25.3 %, but our combined method had a yield of 167+/-31 x 10(8) total cells with a viability of 87.9+/-4.4% (mean +/- SD). Also, the combined method was applied to two pigs of 10kg body weight at the same time, and isolated 387+/-89 x 10(8) hepatocytes with a viability of 87.1+/-6.9% and a purity of 93.6+/-2.8 % in 11 experiments. We designed a large multi-capillary polyurethane foam (MC-PUF) packed-bed module containing 1 x 10(10) porcine hepatocytes on a clinical trial scale. The porcine hepatocytes in the module formed spherical multicellular aggregates (spheroids) of 200 - 500 microm diameter. Most hepatocytes forming spheroids were viable judged by fluorescein diacetate and ethidium bromide staining. The activities of ammonia removal, albumin secretion and oxygen consumption of the large MC-PUF module were the same as for a small MC-PUF module containing 2 x 10(8) porcine hepatocytes, and were maintained for at least 9 days of culture. These results show that a large MC-PUF module is successfully scaled up 50 times. In conclusion, we succeeded in developing a mass preparation method of porcine hepatocytes and a large hybrid artificial liver module on a clinical trial scale.

Animals↗

Polyurethane foam/spheroid culture system using human hepatoblastoma cell line (Hep G2) as a possible new hybrid artificial liver.

The risk of xenozoonosis infections poses the greatest obstacle against the clinical application of hybrid artificial liver support system (HALSS). Primary human hepatocytes are an ideal source for HALSS, but the shortage of human livers available for hepatocyte isolation limits this modality. To resolve this issue, we used human hepatocytes with replication capacity (fetal hepatocytes, Hep G2, and Huh 7) in a polyurethane foam (PUF)/spheroid culture system in vitro, and analyzed liver functions such as ammonia removal and albumin synthesis capacity; results were compared to those of porcine hepatocytes. Human fetal hepatocytes, Hep G2, and Huh 7 formed spheroids spontaneously within 24 h in a PUF/spheroid culture system; ammonia removal activity (micromol/10(6) nuclei/h) was upregulated, as was albumin synthesis activity (microg/10(6) nuclei/day). In particular, Hep G2 spheroids demonstrated high ammonia removal and albumin synthesis activities: 85% of the ammonia removal activity and 171.7% of the albumin synthesis activity of porcine hepatocytes in the monolayer culture. These results indicate the possibility of the development of a multicapillary PUF (MC-PUF) packed-bed culture system of hepatocyte spheroids as a HALSS using Hep G2.

Albumins↗

The impact of donor age on living donor liver transplantation.

BACKGROUND: The impact of the age of the donor on the outcome of living related liver transplantation is yet to be clarified. METHODS: During October 14, 1996 and December 20, 1999, 34 living related liver transplantations were performed. Of these, 26 cases were performed using the extended left lobe graft, which were classified into three groups; younger donor group (group Y, donor age < 30, n = 7), middle-aged donor group (group M, 30 < or = donor age <50, n=13), and older donor group (group O, donor age < 50, n = 6). Early allograft function and regeneration were compared between these groups. RESULTS: There was no difference in standard liver volume, and predicted or harvested graft size between the three groups. Although serum transaminase and total bilirubin levels within postoperative day 7 were not different between the groups, the prothrombin time on postoperative day 3 was significantly longer in group O than in group Y. One week after transplantation, group Y had significantly greater graft/standard liver volume ratio than group O, and greater graft volume than group M and O. One month after transplantation, however, there was no significant difference in such graft size parameters between the groups. Graft and patient survival were comparable between the three groups. CONCLUSION: Although function and regeneration of the allografts from older donors in living donor liver transplantation is worse than those of their younger counterparts, the outcome is not affected by the age of the liver.

Adult↗

Beneficial effect of FR167653 on cold ischemia/reperfusion injury in rat liver transplantation.

BACKGROUND: Proinflammatory cytokines such as interleukin 1-beta (IL-1beta) and tumor necrosis factor-a (TNF-alpha) play an important role in the development of hepatic ischemia/reperfusion injury. FR167653 has been characterized as a potent suppressant of IL-1beta and TNF-alpha production. The aim of this study was to evaluate the effect of FR167653 on cold ischemia/ reperfusion injury in rat liver transplantation. METHODS: Donor livers were preserved with cold University of Wisconsin solution for 48 hr and transplanted orthotopically. Immediately after reperfusion, FR167653 (1 mg/kg, FR-treated group) or normal saline solution (control group) was administered i.v.. The severity of liver injury was determined by hepatic enzyme levels as well as by histological findings. The accumulation of IL-1beta and TNF-alpha mRNA in the liver was analyzed by semi-quantitative reverse transcription-polymerase chain reaction. Tissue factor expression was subjected to immunohistochemical analysis. RESULTS: In the FR-treated group, release of aspartate aminotransferase and alanine aminotransferase after reperfusion was significantly lower (P<0.05 and P<0.02, respectively), and histological liver injury was less prominent, than in the control group. Accumulation of IL-1beta and TNF-alpha mRNA was suppressed in the FR-treated liver. Tissue factor expression on Kupffer cells and sinusoidal endothelial cells, marked in the control group, was almost absent in the FR-treated group. Seven-day survival in the FR-treated group (75%) was significantly better than that in the control group (12.5%) (P<0.01). CONCLUSIONS: These results indicate that treatment with FR167653 ameliorates cold ischemia/reperfusion injury in liver transplantation.

Animals↗

Differential distribution of ionic channels and muscarinic receptors at the cat tracheal neuromuscular junction.

The ionic and pharmacological properties of atropine-sensitive excitatory junction potentials (EJPs) were investigated by the double sucrose gap and microelectrode membrane potential recording methods, and compared with those of inward currents evoked by carbachol (I(CCh)), in cat tracheal smooth muscle. A single and repetitive field stimulation (10-30 V, 50 micros, 20 Hz) evoked atropine-inhibitable EJPs and associated twitch-like contractions. Reduction in external Na+ concentration strongly, but in the external Cl- concentration, decreased the EJP amplitude after 5 min superfusion, although prolonged exposure to low Cl- solutions attenuated the EJPs modestly. Chloride channel blockers such as 9-AC and niflumic acid (each 100 microM), at concentrations high enough to inhibit I(CCh) almost completely, failed to abolish the EJPs. Pirenzepine, AF-DX116 and 4-DAMP all effectively inhibited the EJPs at their concentrations to block respective muscarinic receptor subtypes relatively specifically, while depletion of internal stores by 10 mM caffeine and/or 3 microM ryanodine caused only a partial decrease in the EJP amplitude. These properties are considerably different from those of I(CCh) which is activated exclusively through activation of the M3 receptor/IP3-mediated Ca2+ release pathway and reflects mostly a Ca2+-dependent Cl- current, and suggests the differential distribution of muscarinic receptors and ionic channels inside and outside of the cholinergic neuromuscular junction of this muscle.

Acetylcholine↗

Domino liver transplantation from a living related donor.

BACKGROUND: Although domino liver transplantations (OLT) from cadaveric donors have been performed in about 50 cases since 1995, only one case in the Japanese literature has been reported on a domino OLT from a living related donor. The difficulties of the later surgery lie in the small size of the graft volume and the short length of the vascular cuffs in the graft. METHODS: The left lobe graft was procured from a 43-year-old younger brother of a familial amyloidotic polyneuropathy (FAP) patient. Next, the left lobe graft (510 g, 44% of the estimated standard liver volume of the FAP patient) was implanted into the 48-year-old female FAP patient. At surgery for the FAP patient, a sufficient length of the vascular cuffs was secured by an extended left lobe resection, although the right lobe graft was able to maintain sufficient vascular cuffs. The right lobe graft (720 g, 54% of the recipient's estimated standard liver volume) was then implanted in the 43-year-old male patient with liver cirrhosis and hepatocellular carcinoma (stage IV-A). RESULTS: The two recipients were discharged from the hospital 1 month after OLT. At 7 months after OLT, they are both doing well and the domino recipient is free of any tumor recurrence. CONCLUSION: A domino OLT from the living related donor can therefore be done safely when careful attention is paid to the graft volume and the length of the vascular cuffs for anastomosis.

Amyloid Neuropathies↗

The role of des-gamma-carboxy prothrombin levels in hepatocellular carcinoma and liver tissues.

We aimed to clarify the clinical significance of des-gamma-carboxy prothrombin (DCP) levels in both hepatocellular carcinoma (HCC) and liver tissues with a special reference to the relationship between DCP level in non-cancerous parts of the liver and the multicentric occurrence of HCC. Twenty-eight patients with HCC, who underwent hepatectomy, were studied. Surgical specimens were obtained from both HCC and non-cancerous liver of each patient. After the preparation of the liver tissues, including tissues with HCC, the DCP levels both in HCC and non-cancerous liver tissue were measured using an electro-chemiluminescence immunoassay. The correlation was investigated between DCP levels and other clinicopathological factors. The DCP level of HCC ranged from 55 to 77735 U/0.1 g tissue weight, with a median of 2801, while the DCP level of non-cancerous parts of the liver ranged from 24 to 721 U/0.1 g tissue weight, with a median of 86. The DCP level in the liver tissue in patients having a multicentric occurrence of HCC was significantly higher than that in patients without multicentric occurrence of HCC. The logarithm of the plasma DCP level correlated with that of the DCP level in HCC (correlation coefficient =0.46; P<0.05). No significant correlation was found between the DCP level in HCC and other clinicopathological parameters. The DCP level in non-cancerous parts of the liver with simultaneous multicentric occurrence of HCC was significantly higher than that in the liver without multicentric HCC. Furthermore, the DCP level in non-cancerous parts of the liver was one of the most important predictable factors of the multicentric occurrence of HCCs among various clinicopathological factors. Therefore, the DCP level may have an important role in hepatocarcinogenesis.

Aged↗

Expression of ets-1 transcription factor is correlated with penetrating tumor progression in patients with squamous cell carcinoma of the esophagus.

BACKGROUND: The Ets-1 transcription factor is proposed to play a role in tumor invasion. To evaluate the biologic significance of Ets-1 in the progression of squamous cell carcinoma of the esophagus, the authors investigated Ets-1 expression in tumors from 90 patients using immunohistochemical procedures. METHODS: The Ets-1 positive ratio (Ets-1 ratio) was determined in the center and deep margin areas of invasive sites and in the center and outer edge areas of intraepithelial spread contiguous with invasive disease. RESULTS: Ets-1 expression was heterogeneous within tumor tissue. The Ets-1 ratio was significantly higher at invasive sites compared with intraepithelial spread sites, and at deep margin areas compared with center areas (P < 0.0001 and P < 0.05, respectively, by two-way analysis of variance). No differences were noted in the Ets-1 ratio at the deep margin areas at each depth of invasion. Investigating the Ets-1 ratio at deep margin areas in each pathologic phenotype, the ratio of the small nest type was found to be higher than that of the large nest type (P < 0.0001). CONCLUSIONS: The authors propose that Ets-1 plays an important role in penetrating tumor progression, even very early in the invasive process (especially in the case of infiltrative invasive type tumors) at the deep margin areas of invasive sites in patients with squamous cell carcinoma of the esophagus.

Aged↗

Clip migration causes choledocholithiasis after laparoscopic cholecystectomy.

The migration of surgical clips after laparoscopic procedures was first reported in 1992, but such instances are extremely rare. We herein demonstrate a case of a migrated metal clip, which had been applied originally to the cystic duct, but thereafter had moved to the common bile duct. This clip caused choledocholithiasis in a patient 1 year after a laparoscopic cholecystectomy. A 63-year-old man underwent a laparoscopic cholecystectomy. During the operation, the inflamed cystic duct was divided accidentally, and three clips were applied immediately. The patient complained of upper abdominal pain from postoperative day 8. Endoscopic retrograde cholangiography demonstrated bile leakage from the cystic duct, but showed no clips or choledochal stones. The patient complained of severe upper abdominal and back pain 1 year after the operation. Endoscopic retrograde cholangiography showed a metal clip in the common bile duct and choledochal stones above the clip. The clip and the cholesterol stones were removed using a basket catheter. Three clips applied to the cystic duct should have been removed because of the necrosis in the remaining cystic duct. Thereafter, the clip may have migrated through the stump of the cystic duct into the lower part of the common bile duct. This clip seems to have later caused choledocholithiasis resulting from stagnation of the bile flow. Bile leakage after an operation seems to increase the risk of clip migration. Regardless of the primary lesion, a careful follow-up evaluation is necessary for patients demonstrating complications.

Cholangiography↗