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K Hirohashi

Publications and source records attributed to K Hirohashi.

At least 19 recordsLinked to original sources
PubMed1995

The ultrastructure, kinetics and intralobular distribution of apoptotic hepatocytes after portal branch ligation with special reference to their relationship to necrotic hepatocytes.

Apoptosis was originally defined as shrinkage necrosis, as a distinct mode of cellular death from coagulative necrosis in the rat liver lobes after portal branch ligation. To reveal the functional role of the apoptosis of hepatocytes in the volume reduction and recovery of normal hepatic architecture in portal-deprived liver lobes, we ligated the portal vein branch supplying the left and median liver lobes in Wistar rats. The liver lobes were perfusion-fixed with glutaraldehyde solution via the proximal site of the ligated portion of the portal vein on Days 1, 2, 4, 7 and 14 after operation and examined light and electron microscopically. On Day 2 after ligation, massive necrosis of hepatocytes occurred in the central to intermediate zones of the liver lobule, and apoptotic hepatocytes were observed in the boundary region between necrotic and normal areas. Such necrotic area-associated apoptosis of hepatocytes was most frequent on Day 2, declining thereafter. The sequential changes of the cell organelles in apoptotic hepatocytes were distinct from those in necrotic hepatocytes. On Day 7, when necrotic areas had almost disappeared the apoptosis of hepatocytes occurred mostly between intact hepatocytes in the "combined hepatic cell cords" which included no obvious sinusoidal lumen between hepatic cell cords. Such necrotic area-nonassociated apoptosis began to increase in frequency on Day 4, reached a peak on Day 7 and was gone by Day 14, when normal hepatic architecture was recovered. The present study suggests that both necrotic area-associated and non-associated apoptosis of hepatocytes may be induced by mild ischemia and contribute in part to the volume reduction of ligated liver lobes. It further reveals that the necrotic area-non-associated apoptosis of hepatocytes plays a role in reconstructing the architecture of hepatic cell cords after necrotic hepatocytes have undergone dissolution in the liver lobule.

Animals↗
PubMed1995

Portography in decision-making about indications for liver resection in hepatolithiasis.

We studied the findings of portograms of patients with hepatolithiasis and the role of portography in decision-making about indications for hepatic resection. The subjects were 20 patients in whom hepatic arteriography including the portal phase or percutaneous transhepatic portography was done. We studied the relationships between the findings of the portograms and cholangiograms and hepatic atrophy or associated cholangiocarcinoma. The portal vein in the involved segment of the liver was obstructed in nine patients, and these patients had hepatic atrophy with or without cholangiocarcinoma. There were 16 patients with hepatic atrophy. Four of five other patients in whom protal shrinking was seen had hepatic atrophy. Bile ducts in the involved segment were obstructed in six patients with hepatic atrophy. In all five patients with cholangiocarcinoma, there was portal obstruction at the branching point in the hepatic hilum, with obstruction of the bile ducts at the same point in two of these patients. Hepatic atrophy and cholangiocarcinoma was more closely associated to changes of the portal vein than obstruction of the bile ducts. Portography is useful to diagnose hepatic atrophy and cholangiocarcinoma and for decision-making about indications for hepatic resection in hepatolithiasis.

Adult↗
PubMed1995

Case of hepatolithiasis diagnosed by magnetic resonance cholangiography.

We report a case of hepatolithiasis in which cholangiography by magnetic resonance (MR) imaging was useful in making a detailed diagnosis. Sonograms showed a high echoic lesion in the liver, and computed tomograms showed dilated intrahepatic bile ducts and atrophic hepatic tissue. By ordinary cholangiography, these findings were not made because of obstruction of the bile ducts by the stones. In MR cholangiograms, intrahepatic stones in dilated bile ducts in the posterior segment were seen, as were dilated bile ducts in the peripheral part of this segment. Posterior segmentectomy was done. The operative specimens had stones in the dilated bile ducts, and hepatic tissue was atrophic. MR cholangiography is useful to diagnose not only hepatolithiasis but also dilatation in the bile ducts. MR cholangiography should be tried if other examinations do not give sufficient information.

Calculi↗
PubMed1994

Nucleotide receptors in hepatic stellate cells of the rat.

When hepatic stellate cells were stimulated by UTP, ATP, or ADP, cellular levels of inositol phosphates significantly increased (UTP > ATP > ADP > 5'-O-(3-thiotriphosphate). Thirty min after incubation with 100 microM of UTP, ATP, or ADP, levels of inositol monophosphate increased to 1318 +/- 116, 616 +/- 87 and 591 +/- 234% of control levels, respectively, with concomitant increase in the production of inositol trisphosphate and bisphosphate. These nucleotides transiently increased the [Ca2+]i of fura-2-loaded stellate cells. Moreover, UTP, ATP, ADP and adenosine 5'-O-(3-thiotriphosphate) were able to induce contraction of stellate cells as detected using the silicone-rubber membrane method. These results suggested that hepatic stellate cells have nucleotide receptors which react predominantly with extracellular UTP and ATP and trigger the receptor-mediated contraction of the cells.

Animals↗
PubMed1994

Increased safety by two-stage hepatectomy with preoperative portal vein embolization in rats.

We evaluated the usefulness of preoperative portal vein embolization (PVE) in rats for increasing the safety of liver resection. During PVE, portal vein branches that perfused the central and left lobes of the liver were embolized. Liver weight, the elimination of indocyanine green, and the number of Kupffer cells were examined 7 days after PVE and in intact rats. Then we examined rats that had undergone PVE (PVE group), rats in which the embolized part of the liver was resected 7 days after PVE (PVE-Hx group), rats without PVE in which the same lobes of the liver were resected (Hx group), and rats that had undergone a sham operation (sham-operation group) for liver weight, the mitotic index of the hepatocytes, serum alanine aminotransferase activity, total bilirubin, and antithrombin III activity. Some rats in the four groups received an intravenous injection of 0.5 or 2.5 mg/kg endotoxin 48 hr after the operation (the second operation, if done), and the 24-hr survival rate was calculated. Some rats given 0.5 mg/kg endotoxin were killed 6 hr after the injection, and the extent of liver injury was examined biochemically and histologically. Seven days after PVE, the nonembolized part of the liver was about twice the weight of the corresponding lobes in the intact rats, the density of Kupffer cells was doubled, and the hepatic function per unit weight was about the same as that in these controls. Hepatic dysfunction and the endotoxin-induced liver injury were significantly slighter in the PVE and PVE-Hx groups than in the Hx group. Preoperative PVE could make hepatectomy safer.

Alanine Transaminase↗
PubMed1994

The distribution of secretory immunoglobulin A in the intrahepatic biliary epithelium of patients with hepatolithiasis.

In the treatment of hepatolithiasis, liver resection helps to prevent recurrence and may reduce the incidence of infection by removal of the atrophic tissue. This study was conducted to determine if the affected liver tissue in hepatolithiasis is inflamed or has lowered local immunity by examining the distribution of secretory immunoglobulin A (sIgA) and proliferating cell nuclear antigen (PCNA) in the intrahepatic biliary tracts of 27 patients with hepatolithiasis. Operative specimens were sectioned and stained with avidinbiotin complex, and the labeling index for both sIgA and PCNA was calculated as a percentage of the biliary epithelial cells stained. Cells stained for sIgA increased to a certain point as the cholangitis became more severe; however, in advanced cholangitis, with severe parenchymal atrophy or actively proliferating biliary epithelium, there were fewer cells stained for sIgA than in mild cholangitis. In hepatolithiasis, the decreased local immunity related to sIgA accompanied severe chronic proliferative cholangitis and parenchymal atrophy.

Bile Ducts, Intrahepatic↗
PubMed1994

Case of perforated peptic ulcer treated conservatively.

We report a patient fifty-one-year old man with peptic ulcer which was treated conservatively. His chief complaints were epigastric discomfort and tarry stool. On admission, no fever was noted, the abdomen was flat and extremely hard, tenderness was noted, and peritoneal rebound was absent. Laboratory data on admission were all normal except for a slightly elevated CRP level. Oral intake was suspended and the patient received infusion. The chest X-ray film on the following day revealed free air, and the diagnosis of perforation of the upper digestive tract was confirmed; however, the symptoms and signs of peritonitis diminished. Therefore, he was treated conservatively. This case suggests that the conventional indications for emergency surgery for perforated peptic ulcer should be re-evaluated.

Anti-Ulcer Agents↗
PubMed1994

[Surgical treatment for cardiac diseases in patients with concomitant malignant tumor].

Between April 1984 and December 1992, 8 patients with concomitant malignant tumor were treated surgically for cardiac disease. The mean age was 58 years (range: 51 to 69), and there were 6 males and 2 females. There were 2 cases of ischemic heart disease, 3 cases of valvular heart disease, and 1 case of atrial septal defect (ASD). Gastric cancer was present in 4 cases, malignant tumor of hepatobiliary tract in 2, rectal cancer in 1, and lung cancer in 1. All patients were operated on in a two-stage fashion. In 6 cases, cardiac surgery including coronary artery bypass grafting (4 patients) and valve replacement (2 patients) were performed with an average of 58 days prior to the tumor resection. The other 2 patients underwent radical operation for a gastric or rectal cancer, followed by cardiac surgery for ASD or mitral stenosis about 2 months later. One patient died of respiratory failure 56 days after lobectomy following coronary artery bypass. There was one late death of local recurrence of rectal cancer 2 years after the operation. In conclusion, good surgical result can be expected with sequential operations for cardiac disease and malignant tumor, if curative resection of the tumor is possible.

Aged↗
PubMed1994

[Two-stage hepatectomy with preoperative portal vein embolization in rats].

We studied the functional reserve and ability to regenerate of non-embolized liver made hypertrophic by portal vein embolization (PVE) to evaluate the usefulness of two-stage hepatectomy with preoperative PVE. Rats underwent one of four treatments: 1, 70% hepatectomy; 2, 70% hepatectomy 7 days after PVE; 3, 30% hepatectomy; and 4, sham operation. Liver weight, the bromodeoxyuridine labeling index (LI), and the mitotic index (MI) were calculated after surgery. The lipid peroxide level of the liver, serum hepatic enzyme activities, total bilirubin concentration, prothrombin time, and antithrombin-3 activity were also assayed after surgery in each group. Non-embolized lobes made hypertrophic by PVE regenerated further after resection of the embolized portion of the liver. The increases in liver weight, LI, and MI in group 2 were significantly lower than in group 1, but tended to be higher than in group 3. In group 2, lipid peroxidation in the liver and postoperative disorders of liver function and the coagulation system were significantly less than in group 1, and were similar to those in group 3. Preoperative PVE increases not only the weight but also the function of the residual liver, which makes extended hepatectomy safer.

Animals↗
PubMed1993

[Indication and limitation of hepatectomy for hepatocellular carcinoma].

Hepatectomy for hepatocellular carcinoma (HCC) has become safer with recent advances in diagnostic methods, operative techniques and understanding of how to evaluate liver function. Hepatectomy is the treatment of choice for HCC provided that patients are selected carefully, because cure is possible with hepatectomy (some patients survive long without recurrence). However, the rate of recurrence after hepatectomy is high. Recurrences can arise because of either intrahepatic dissemination or factors that give rise to multicentric carcinoma, so one must decide the operative method, to prevent recurrence and the treatment if such occurs, based on the pathogenesis of HCC.

Carcinoma, Hepatocellular↗
PubMed1992

[Preoperative percutaneous transhepatic portal vein embolization to extend the indications for hepatectomy and to increase the safety of extended hepatectomy for hepatocellular carcinoma].

The usefulness of preoperative percutaneous transhepatic portal vein embolization (PTPE) in extending the indications for hepatectomy and increasing the safety of extended hepatectomy for hepatocellular carcinoma was studied in 21 patients who underwent right hepatic lobectomy with PTPE of the right first portal branch (group E), in 15 such patients but without PTPE (group N), and in seven such patients who underwent PTPE at this location but could not undergo surgery (group U). The mean volume of the left lobe increased but the results of a 15-minute indocyanine green retention test were worsened 2 weeks after PTPE and again 4 weeks after hepatectomy, but these changes after hepatectomy were almost the same in groups E and N. The worsening of liver function and coagulation test results was less in group E than in group N. The mean prognosis score was better in group E two weeks after PTPE than before, but not in group U. The four patients in group E with high portal vein pressure (> or = 30 cmH2O) or a high prognosis score (> or = 50 points) after PTPE developed hepatic failure after surgery. Preoperative PTPE was useful in extending the indications for hepatectomy and increasing the safety of extended hepatectomy. Evaluation of the clinical course after PTPE was also useful when decisions about the operative method to be used were being made.

Aged↗
PubMed1991

[Preoperative portal vein embolization for hepatocellular carcinoma].

We performed preoperative portal vein embolization (PVE) for 71 patients with hepatocellular carcinoma (HCC), 59 of whom underwent hepatectomy about two weeks after PVE. The purpose of the PVE was usually to embolize the portal vein supplying the area to be resected. After PVE, the non-embolized part of the liver became hypertrophic and the embolized part of the liver became atrophic. Of the 22 patients who underwent right lobectomy after PVE of the right first branch of the portal vein, the mean results of a test of 15-minute indocyanine green retention after PVE increased significantly less than the mean for six patients who could not undergo right lobectomy after PVE of their right first branch. The extent of this increase and the liver volume of the left lobe 4 weeks after right lobectomy were higher in another 15 patients who did not undergo PVE than 22 patients who underwent PVE. PVE is useful as one preparation for hepatectomy of patients with HCC, because the embolized part of the liver was damaged by PVE, but mean liver function was compensated by the part of the liver that was not embolized and regenerated.

Carcinoma, Hepatocellular↗
PubMed1990

Clinical courses and treatment of splenic artery aneurysms--report of 3 cases and review of literatures in Japan.

We have treated three cases of splenic artery aneurysms recently, so we reported them with a review of 181 cases in Japan. All three cases are women and have characteristic clinical courses and pathogenesis in each to which we performed a reasonable operation so that they could be saved. First one is a ruptured case. So we performed ligation of the splenic artery from inside the aneurysm under 9 min.'s clamp of the aorta. Second one was pointed out the splenic artery aneurysm during admission for cholecystectomy, so we performed splenectomy and aneurysmectomy, and after that we reconstructed the splenic artery with end-to-end anastomosis. Third one suffered from splenomegaly and portal hypertension. We performed splenectomy with the aneurysm. From the clinical and pathological findings, we concluded that an aneurysm in our first case was associated with arterial dysplasia, second with hemodynamic changes in parous women, and third with portal hypertension. Aneurysms of the splenic artery have been rarely reported until recently, when developments in diagnostic procedures made their discovery easier. We have diagnosed splenic artery aneurysm in three patients preoperatively. The clinical symptoms and operative procedure was different in each case, and are reported here. We demonstrated the summary of our three cases of that at Table 1.

Aneurysm↗