[Tolvaptan, a vasopressin V2 receptor antagonist, is the world's first approved drug for treatment of autosomal dominant polycystic kidney disease (ADPKD)]

Autosomal dominant polycystic kidney disease (ADPKD) is the most common genetic kidney disease. Fluid-filled cysts develop and enlarge in both kidneys, eventually leading to kidney failure. Tolvaptan is a selective vasopressin V₂ receptor antagonist and the first and only drug approved for treatment of ADPKD. It blocks binding of arginine vasopressin (AVP) to V₂ receptors in the collecting duct of kidney, thereby inducing water diuresis (aquaresis) without losing electrolytes. Therefore, tolvaptan was originally developed and approved as the first oral aquaretic agent for treatment of hyponatremia and fluid volume overload in heart failure and cirrhosis. During the development of tolvaptan as aquaretics, efficacy of V₂ antagonist in polycystic kidney animal model was reported and then the development of tolvaptan for ADPKD was also initiated. Cyclic adenosine monophosphate (cAMP) plays an important role in cyst growth by promoting cell proliferation and fluid secretion. Tolvaptan showed suppression of cyst growth through inhibiting AVP-induced cAMP production and delayed the onset of end-stage renal disease in an animal model. In the phase 3 clinical trial in ADPKD patients (TEMPO 3:4 trial), 3-year treatment with tolvaptan slowed the disease progression including increase of kidney volume and decline in renal function. Efficacy of tolvaptan in patients with late-stage ADPKD was confirmed in another 1-year phase 3 REPRISE trial. Tolvaptan is approved for treatment of ADPKD in more than 40 countries and we expect it can contribute to more ADPKD patients worldwide. We also expect that drugs with new mechanisms will be available in the near future.

Tolvaptan delays the onset of end-stage renal disease in a polycystic kidney disease model by suppressing increases in kidney volume and renal injury

Tolvaptan, a selective vasopressin V2 receptor antagonist, slows the increase in total kidney volume and the decline in kidney function in patients with the results of the Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Outcome (TEMPO) 3:4 trial. However, it was unclear which dose of tolvaptan was optimal or whether tolvaptan was able to delay progression to end-stage renal disease (ESRD). Here we examined the relationship with aquaresis and the inhibitory effect on cyst development in short-term treatment and mortality as an index of ESRD in long-term treatment with tolvaptan using DBA/2FG-pcy mice, an animal model of nephronophthisis. With short-term treatment from 5 to 15 weeks of age, tolvaptan (0.01-0.3% via diet) dose-dependently enhanced aquaresis, prevented increases in kidney weight and cyst volume, and was associated with significant reductions in kidney cAMP levels and extracellular signal-regulated kinase activity. Maximal effects of tolvaptan on aquaresis and the prevention of development of polycystic kidney disease (PKD) were obtained at 0.1%. Interestingly, tolvaptan also dose-dependently reduced urinary neutrophil gelatinase-associated lipocalin levels in correlation with the kidney volume. With long-term treatment from 5 to 29 weeks of age, tolvaptan significantly attenuated the increase in kidney volume by up to 50% and reduced urinary albumin excretion. Furthermore, tolvaptan significantly reduced the mortality rate to 20%, compared with 60% in the control group. These data indicate that tolvaptan may delay the onset of ESRD in PKD by suppressing the increases in kidney volume and renal injury, providing a promising treatment for PKD.

Genetic screening for regulators of Prz1, a transcriptional factor acting downstream of calcineurin in fission yeast

Calcineurin phosphatase plays crucial roles in a wide variety of cell types and organisms. Dephosphorylation of the nuclear factor of activated T-cell (NFAT) family of transcriptional factors by calcineurin is essential for activating immune-responsive genes in mammals. NFAT activity is also regulated by diverse signaling pathways, which affect NFAT kinases and nuclear partner proteins. In fission yeast, calcineurin dephosphorylates and activates Prz1, a C2H2-type zinc finger transcriptional factor. Calcineurin-Prz1 signaling regulates the expression of the Pmc1 Ca(2+) pump. Prz1-overexpressing cells showed extremely slow growth and high transcriptional activity of Prz1 in the absence of stimulation. Here, we isolated seven genes as dosage-dependent suppressors of this slow growth phenotype. These seven genes encode Rad24, Rad25, Pka1, Msn5 (SPAC328.01c), Pac1, Ape2, and Tfs1. All of them decreased the high transcriptional activity caused by Prz1 overexpression. Overexpression of Pka1, Rad24, and Rad25 also repressed the Ca(2+)-induced transcriptional activity in cells with Prz1 expressed at wild-type levels. Knock-out of rad24 or rad25 significantly enhanced the transcriptional activity of Prz1, whereas knock-out or mutation of other genes did not enhance the activity. The 14-3-3 proteins, Rad24 and Rad25, bound Prz1 and the Rad24-binding site located at residues 421-426 of Prz1. In msn5 deletion mutants, GFP-Prz1 localized at nucleus in the absence of Ca(2+) stimulation, suggesting that Msn5 functions as an exportin for Prz1. In summary, our data suggest that Rad24 and Rad25 negatively regulate Prz1 and that Pka1, Msn5, Pac1, Tfs1, and Ape2 also regulate Prz1.

Chronic hyponatremia impairs memory in rats: effects of vasopressin antagonist tolvaptan

The effects of stable chronic hyponatremia on the central nervous system are largely unknown, clinically, or in experimental animals. The aim of this study was to identify and characterize these effects in rats. Tolvaptan, a vasopressin V(2) receptor antagonist, was used to correct hyponatremia and determine any potential benefits of such treatment in this condition. Stable chronic hyponatremia was induced by combination of the continuous vasopressin V(2) receptor stimulation and liquid food intake. The hyponatremic rats did not exhibit significant changes in general symptoms or neurological functions assessed by modified Irwin's method, or in motor function assessed by the rotarod test. In passive avoidance test, however, rats with moderate and severe hyponatremia had significantly reduced step-through latency, indicating impairment in memory. This reduced step-through latency was improved by the treatment of tolvaptan (0.25-8 mg/kg daily doses), a vasopressin V(2) receptor antagonist. This improvement is associated with normalization of plasma sodium concentrations in hyponatremic rats. In conclusion, these data suggest that chronic hyponatremia may impair memory, and treatments that normalize sodium level, such as vasopressin V(2) receptor antagonists, may be beneficial to patients with hyponatremia.

Nodulisporic acid A synthetic studies. 1. Overall strategy and construction of a western hemisphere subtarget

In this, the first of two Letters, we outline our overall strategy for the construction of (+)-nodulisporic acid A (1), a representative member of a new class of indole diterpenes. In addition, we describe the efficient assembly of (-)-6, an advanced western hemisphere subtarget, comprising the ABC rings of (+)-nodulisporic acid A (1). The synthesis proceeded in 9% overall yield (longest linear sequence, 11 steps), exploiting a Shibasaki-Mori tandem transmetalation-cyclization to construct ring B. [reaction: see text]

Design and synthesis of new orally active inhibitors of human neutrophil elastase

To identify new orally active inhibitors, further modification of 1 (ONO-6818) was performed. Peptidic derivatives 4b, 4c and 4n showed more potent inhibitory activity than nonpeptidic derivatives 3a-c. As a result, a series of peptidic inhibitors, 4a-s and 5a-v, were discovered. Among these N-aryl derivatives 5a-g, 5i, 5m and 5o-v showed oral activity. Their oral activity showed good correlation with their metabolic stability. Compounds 5h and 5j-l, which were extremely metabolically unstable in hamster plasma, did not show oral activity. Oral activity was considered to be determined by a combination of at least two factors: oral absorption and metabolic stability.

Development of orally active nonpeptidic inhibitors of human neutrophil elastase

5-Amino-2-phenylpyrimidin-6-ones, some of their desamino derivatives, and miscellaneous derivatives were synthesized and biologically evaluated on both in vitro activity and oral activity in an acute hemorrhagic assay. These compounds contained an alpha-keto-1,3,4-oxadiazole moiety to bind covalently to the Ser-195 hydroxy group of human neutrophil elastase (HNE). Among those tested, compounds 11a-c,e,i-l(F), 11d,e,k(H), 21d,e,k(F), and 21d,e(H) showed a good oral profile. RS-Mixture 3(H) was selected for clinical evaluation based on its oral potency, duration of action, enzyme selectivity, safety profile, and ease of synthesis. Structure-activity relationships (SARs) are discussed.

The crystal structure of the complex of non-peptidic inhibitor of human neutrophil elastase ONO-6818 and porcine pancreatic elastase

The crystal structure of a new inhibitor of human neutrophil elastase (HNE), N-[2-[5-(tert-butyl)-1,3,4-oxadiazol-2-yl]-(IRS)-1-(methylethyl)-2-oxoethyl]-2-(5-amino-6-oxo-2-phenyl-6H-pyrimidin-1-ly)acetamide (ONO-6818, 1) complexed to porcine pancreatic elastase (PPE) has been determined at 1.86 A resolution. Analytical results provided evidence of a 1:1 complex in which the electrophilic ketone of 1 covalently bound to O gamma of Ser195 at the active site of PPE. The role of the unique electron-withdrawing ketone of 1 has been elucidated.

[Factors leading to home care of patients in the terminal stage of malignant diseases--a study of 10 cases]

In order to clarify the factors that lead patients in the terminal stage of malignant diseases to home care, we interviewed ten families of such patients. Among factors involving patients, a strong desire to stay at home and to spend time at home with the family were initially required. Adequate understanding of the patients and their diseases was also needed by families. Other factors include guaranteed medical services in emergencies and/or 24 hours/day 7 days/week care. Patients requested referrals to family physicians, visiting nurses or community health services to cover outpatient clinic functions. It is concluded that a strong desire to stay at home, adequate understanding by the family and guaranteed medical services in emergencies were three significant factors leading to home care of patients in the terminal stage of malignant diseases.

CT appearance of hepatic parenchymal changes after percutaneous microwave coagulation therapy for hepatocellular carcinoma

PURPOSE

The purpose of this study was to evaluate the changes in the CT appearance of the hepatic parenchyma surrounding the necrotic area in the early period after percutaneous microwave coagulation therapy (PMCT) for hepatocellular carcinoma (HCC).

METHOD

We reviewed enhanced CT scans obtained before and within 2 weeks, at 1 month, and at 3 months after PMCT of 61 lesions in 47 patients with HCC.

RESULTS

On dynamic CT, early enhancement of the hepatic parenchyma around the treated area was a frequent finding within 1 (87%) or 2 (68%) weeks after PMCT, but such enhancement disappeared on follow-up. Arterioportal shunts were also demonstrated by enhanced CT after treatment (21% at < or =2 weeks), and these shunts tended to persist for >1 month.

CONCLUSION

We should evaluate the effect of PMCT by performing dynamic enhanced CT not only within 2 weeks to determine the end-point of treatment but also at 1 month or more after finishing treatment for definite assessment of tumor necrosis.

Hepatic angiosarcoma with early central enhancement and arterioportal shunt on dynamic CT

We report a case of hepatic angiosarcoma that is usually difficult to differentiate from cavernous hemangioma on computed tomography. The present case suggests that early central enhancement and arterioportal shunting on dynamic computed tomography might be helpful for distinguishing hepatic angiosarcoma with a solid growth pattern from benign vascular neoplasms of the liver such as cavernous hemangioma.

Mercury evaporation from amalgams with varied mercury contents

This study examined the relationship between mercury content and mercury evaporation from amalgams during setting. Two different types of commercial high-copper amalgams (single composition and admixed types) were used. Cylindrical specimens of each amalgam were prepared with five different mercury contents according to ADA Specification No.1. Specimens were also prepared by hand condensation. Mercury evaporation from amalgam specimens maintained at 37 degrees C was measured using a gold film mercury analyzer from 10 min after the end of trituration until the mercury concentration in air reached an undetectable level. The mercury content more clearly influenced the mercury evaporation from the admixed type amalgam specimens when the mercury content decreased below the manufacturers' recommended trituration conditions. Triturating with less mercury than the manufacturers' recommended amount cannot lower the evaporation of mercury from freshly made amalgam. Proper condensing procedures can minimize the mercury evaporation from the amalgam surface.

Intraperitoneal hemorrhage as a major complication of percutaneous ethanol injection therapy for hepatocellular carcinoma

Two cases of intraperitoneal hemorrhage, which is one of the major complications of percutaneous ethanol injection therapy for hepatocellular carcinoma, are reported. A 70-year-old man was hospitalized for treatment of a small recurrent hepatocellular carcinoma located on the surface of the left lobe of the liver. Acute hemoperitoneum developed after percutaneous ethanol injection therapy, but he was treated conservatively with blood transfusion, and recovered. The other patient was a 72-year-old man who was admitted for treatment of a solitary superficial hepatocellular carcinoma on the dome of the liver. Immediately after percutaneous ethanol injection, he suffered the sudden onset of severe abdominal pain with shock and massive hemoperitoneum. His bleeding was successfully controlled by emergency transcatheter arterial embolization. Our experience suggests that care must be taken when using percutaneous ethanol injection to treat patients with superficial hepatocellular carcinomas located on the surface of the liver. Moreover, transcatheter arterial embolization should be considered the treatment of choice for the management of uncontrollable intraperitoneal hemorrhage after percutaneous ethanol injection therapy.

Percutaneous microwave coagulation therapy for hepatocellular carcinoma located on the surface of the liver

OBJECTIVE

Percutaneous microwave coagulation therapy was recently introduced as a new treatment for hepatocellular carcinoma in our country. We performed this study to evaluate the efficacy and safety of this therapy for treatment of hepatocellular carcinoma, especially for tumors located on the surface of the liver.

CONCLUSION

Percutaneous microwave coagulation therapy can be performed safely even in patients with cirrhosis and can achieve complete remission of small hepatocellular carcinomas (< or = 2.0 cm) located on the surface of the liver.

Percutaneous microwave coagulation therapy for unresectable hepatocellular carcinoma

BACKGROUND/AIMS

Percutaneous microwave coagulation therapy (PMCT) has recently been introduced as a new treatment for hepatocellular carcinoma (HCC) in Japan. This study was performed to evaluate its efficacy and safety.

METHODOLOGY

Thirteen patients with 17 nodules of unresectable HCC were subjected to PMCT under ultrasonic guidance. The tumors ranged from 1.2-4.4 cm in size. Assessment of the efficacy of PMCT was made by follow-up with dynamic computed tomography (CT).

RESULTS

In the patients with small HCC (< or = 2.0 cm), 8 of 10 nodules (80%) showed complete remission after PMCT. In small nodules located on the liver surface, 3 out of 4 nodules (75%) showed complete remission. However, in the patients with larger HCC (> or = 2.1 cm), 5 out of 7 nodules developed local recurrence after PMCT. Regarding assessment of the necrotic area after PMCT, dynamic CT revealed enhancement that was possibly caused by congestion of the liver parenchyma surrounding the area of necrosis due to PMCT in the early phase of the treatment. Therefore, the necrotic area must be assessed carefully. Although a slight heat sensation and/or pain during microwave irradiation (a common effect of PMCT) occurred in all patients, there were no serious adverse effects.

CONCLUSIONS

Complete remission of small HCC (< or = 2 cm in diameter) can be achieved with PMCT alone, but there seem to be limitations to its effectiveness with larger HCC (> or = 2.1 cm). There were no serious adverse effects from PMCT and the therapy can be safely carried out even in patients with poor liver function.

Severe acute pancreatitis associated with hyperlipidemia: report of two cases and review of the literature in Japan

Two cases of severe acute pancreatitis associated with type V hyperlipoproteinemia are reported. A 39-year-old obese woman was hospitalized with continuous severe abdominal pain. The diagnosis was made on the day of admission to our hospital, and treatment using continuous regional arterial infusion of a protease inhibitor and an antibiotic was performed with good results. The other patient was a 35 year-old woman in the 35th week of pregnancy, and a diagnosis of gestational hyperlipidemic pancreatitis was made on the day of onset. She was treated supportively using intravenous hyperalimentation, protease inhibitors, and antibiotics. She recovered from the acute pancreatitis and delivered a healthy term infant. It is difficult to diagnose acute pancreatitis in patients with type V hyperlipoproteinemia, because even when serum amylase levels are high, the value is reduced by high serum triglycerides. Early diagnosis was achieved in both of the present cases, and early intensive therapy was performed, which may be of the utmost importance in saving the life of a patient.

Percutaneous microwave coagulation therapy for superficial hepatocellular carcinoma

We report a 67 year-old man with residual hepatocellular carcinoma after arterial embolization therapy, which was located on both the anterior and inferior surfaces of segment 6 of the liver. Percutaneous microwave coagulation therapy could be performed safely and the treated tumor became non-enhancing on contrast computed tomography. Two years after treatment, the tumor remains non-enhancing on contrast computed tomography and has decreased in size. Percutaneous microwave coagulation therapy appears to be useful even in patients who have superficial liver tumors associated with cirrhosis.

Control of solitary gastric fundal varices and portosystemic encephalopathy accompanying liver cirrhosis by balloon-occluded retrograde transvenous obliteration (B-RTO): a case report

In a patient with liver cirrhosis complicated by solitary gastric fundal varices and portosystemic encephalopathy, Balloon-occluded retrograde transvenous obliteration (B-RTO) of the varices was performed. The gastric varices were decreased in size 2 weeks after treatment and had not recurred after 1 year. B-RTO successfully occluded the portosystemic shunt (gastrorenal shunt). Accordingly, the patient's blood ammonia levels, total bile acid level, and 15 min retention rate of indocyanine green decreased, and his hepatic encephalopathy improved. However, since consecutive increase in blood flow through the portal collateral vessels except for gastrorenal shunt vessel at 6 months and 1 year after B-RTO was noted, further careful follow-up may be required.

[Percutaneous ethanol injection for unresectable pancreatic cancer-report of two cases]

Two cases of unresectable pancreatic cancer underwent percutaneous ethanol injection (PEI). The first was a 65-year-old man with a 43 x 39 mm mass in the head of the pancreas. He received PEI (total 38.5 ml of ethanol) 6 times. Serum CA19-9 decreased from 3,800 U/ml to 1,700 U/ml. The patient was dead 6 months after PEI. Autopsy revealed coagulative necrosis at the site of ethanol injection. The second case was a 66-year-old man with a 70 x 50 mm mass in the body of the pancreas. He was treated by PEI (total 10 ml). After PEI, his abdominal pain was relieved considerably. He died 4 months after PEI treatment. These findings suggest that PEI may be useful not only for pain control but also for tumor reduction of unresectable pancreatic cancer.

Expression of cytotoxic molecule TIA-1 in malignant lymphomas mimicking fulminant hepatitis

Involvement of malignant lymphoma in the liver inducing fulminant hepatic failure has rarely been reported. Therefore, a close association between some lymphoma types with severe liver damage and the mechanism underlying the liver damage is intriguing. Three malignant lymphoma cases, which were clinically diagnosed as fulminant hepatitis, were collected from the autopsy records of Kawasaki Medical School (Kurashiki, Japan). All three cases were characterized by the presence of hepatosplenomegaly without superficial lymph node swelling, high elevation of transaminase and lactate dehydrogenase (LDH; especially LDH-2), and a quite aggressive clinical course. Immunohistochemically, the tumor cells in all three cases were positive for T cell intracellular antigen (TIA-1), which is a cytolytic protein in cytotoxic T and natural killer (NK) cells. The lymphomas were CD8+ peripheral T cell lymphoma (case 1), CD56+ T/NK cell lymphoma (case 2), and T cell lymphoma in a patient with mosquito hypersensitivity (case 3). Epstein-Barr virus infection was demonstrated on the tumor cells of cases 2 and 3 using an in situ hybridization method and those cases showed high titers of serum interferon-gamma and Fas. Frequent apoptosis of liver cells, where the lymphoma cells had infiltrated, was revealed by a terminal deoxyribosyl transferase-mediated deoxyuridine nick end-labeling (TUNEL) method. The findings in this study suggest that fulminant hepatic injury is closely associated with cytotoxic molecule TIA-1 expression of the lymphoma cells and that some specific mechanism may be involved in liver damage.

Acute terminal pancreatitis occurring in jejunal heterotopic pancreas

CONCLUSION

We report a unique case of acute terminal pancreatitis occurring in the jejunal heterotopic pancreas. Unlike previously reported cases, acute pancreatitis was not found histologically in the ordinary pancreas.

BACKGROUND

Heterotopic pancreas may show the same inflammatory or neoplastic changes, such as acute pancreatitis and adenocarcinoma, as those that occur in the ordinary pancreas. However, histologically proven acute pancreatitis occurring in heterotopic pancreas is very rare and only three reports have been described.

METHODS

A 53-yr-old Japanese man died of hepatic failure, and autopsy was performed.

RESULTS

Autopsy incidentally revealed heterotopic pancreas of the jejunum. Microscopically, focal acute pancreatitis was observed in the jejunal heterotopic pancreas, whereas the pancreas of the normal location showed no abnormality. In addition, no clinical evidence of pancreatic disease was noted before death. Therefore, we diagnosed this case as acute terminal pancreatitis occurring in the jejunal heterotopic pancreas.

Zinc metabolism after transcatheter arterial embolization for hepatocellular carcinoma

BACKGROUND/AIMS

Zinc metabolism after transcatheter arterial embolization (TAE) was studied in 15 cases of hepatocellular carcinoma (HCC) with liver cirrhosis (LC).

METHODOLOGY

Serum zinc concentrations, 24-hr urinary excretion of zinc, blood ammonia (NH3) and plasma endotoxin (Et) levels were measured before and one, three and seven days after TAE.

RESULTS

Serum zinc levels one day after TAE were decreased (p<0.05) as compared to those before TAE and then returned to pretreatment values three days or more after TAE. Urinary excretion of zinc increased (p<0.01) one day after TAE, but then returned to the pretreatment value three days after TAE. Although blood NH3 and plasma Et levels increased (P<0.05) the day after TAE, these parameters recovered on the third day.

CONCLUSIONS

Decrease in the serum zinc concentration after TAE is considered to be due to changes in the zinc distribution in the body associated with endotoxemia, as well as increased urinary zinc excretion.

Acute terminal pancreatitis occurring in jejunal heterotopic pancreas

CONCLUSION

We report a unique case of acute terminal pancreatitis occurring in the jejunal heterotopic pancreas. Unlike previously reported cases, acute pancreatitis was not found histologically in the ordinary pancreas.

BACKGROUND

Heterotopic pancreas may show the same inflammatory or neoplastic changes, such as acute pancreatitis and adenocarcinoma, as those that occur in the ordinary pancreas. However, histologically proven acute pancreatitis occurring in heterotopic pancreas is very rare and only three reports have been described.

METHODS

A 53-yr-old Japanese man died of hepatic failure, and autopsy was performed.

RESULTS

Autopsy incidentally revealed heterotopic pancreas of the jejunum. Microscopically, focal acute pancreatitis was observed in the jejunal heterotopic pancreas, whereas the pancreas of the normal location showed no abnormality. In addition, no clinical evidence of pancreatic disease was noted before death. Therefore, we diagnosed this case as acute terminal pancreatitis occurring in the jejunal heterotopic pancreas.

Effect of Pd and In on mercury evaporation from amalgams

The amount of Hg vapor released from "synthesized" gamma 1 with 1% (wt) Pd was reported to be less than 30% of that from gamma 1 with no Pd. This study tested the hypothesis that Hg evaporation from Pd-containing amalgams decreases with Pd concentration and that In also reduces Hg vapor. Specimens (4 mm dia, 8 mm long) were prepared by triturating Ag-Sn(25%)-Cu(12%) alloy powder containing 0.5-9.0% Pd with pure Hg and by triturating 3% Pd alloy powder with Hg containing 1-5% In (all residual Hg approximately equal to 62%). The total amount (ng/mm2) of Hg vapor released at 37 degrees C from freshly prepared amalgams was measured. Pd (3-9%) in the powder significantly (p < 0.05) decreased Hg vapor release from amalgams during setting. Use of In-containing Hg also reduced Hg vapor release (5% In, p < 0.05). The reduction in the Hg vapor pressure by adding Pd and the rapid oxide film formation on the In-containing amalgam appear to work together to reduce Hg vaporization from these amalgams.

Solitary cystic dilatation of the intrahepatic bile duct

A 31 year old man was hospitalised with general fatigue and epigastric pain. Abdominal ultrasonography, computed tomography, and magnetic resonance imaging showed a cystic lesion in the left lobe of the liver. Endoscopic retrograde cholangio-pancreatography and percutaneous trans-hepatic cholangiography revealed a localised dilatation of the intrahepatic bile duct without any obstruction. However, a large mass of mucinous material was noted in the saccular intrahepatic duct and the common bile duct. There was no evidence of a choledochal cyst, anomalous pancreaticobiliary ductal union, or congenital cystic change of the kidneys. A possible diagnosis of mucinous cystic neoplasm of the intrahepatic bile duct was made and a left hepatectomy performed. Cholangiography of the resected specimen showed a non-obstructive solitary cystic dilatation of the left hepatic duct. Histologically, the dilated duct was lined with columnar biliary epithelium without any papillary proliferation and/or atypia. Neither malignancy nor hepatic fibrosis was observed; the term "solitary cystic dilatation of the intrahepatic bile duct" perhaps is more descriptive and the concept easier to understand.

Studies on dental high-speed cutting

The primary author, an experienced dentist, cut bovine enamel and dentine horizontally and vertically with diamond points driven by an air-turbine, while the rotational cutting speeds and applied loads were simultaneously monitored. Three cutting techniques employed here were successive cutting with moderate force (S-m); intermittent cutting with moderate force (I-m); and intermittent cutting with a smaller force (I-s). It was found that the cut contact time of S-m, I-m and I-s cuts were about 10s, 0.4s and 0.25 s, respectively. The maximum applied load during cutting varied, depending upon the cutting direction and the cutting technique. Vertical S-m cut of enamel resulted in the largest applied load of around 105 g, while horizontal I-s cut of dentine brought about the minimum (approximately 35 g). Cutting volumes of dentine tended to exceed those of enamel. It was confirmed that the I-m cut produced larger cutting effectiveness of diamond points on both enamel and dentine compared with the S-m cut.

Mucinous cystadenocarcinoma of the pancreas with mucinous biliary obstruction due to uncommon complication of fistulas to the common bile duct and main pancreatic duct

We report a case of biliary obstruction by a large amount of mucinous material produced by a cystadenocarcinoma of the pancreas invading the common bile duct. This diagnosis was made preoperatively by various imaging methods. Endoscopic retrograde pancreatography (ERP) revealed a mucus-containing cyst with a communication to the main pancreatic and common bile ducts due to a fistulization. Mucinous biliary obstruction was observed. This case indicates that mucinous biliary obstructions should be considered in patients with a mucinous cystic neoplasm of the pancreatic head in the presence of jaundice and that mucinous cystadenocarcinoma may develop into mucinous carcinoma, especially in cases with fistula formations. ERP is useful for detecting the presence of a fistula to the common bile duct or other neighboring organs in such cases. Surgical treatment is recommended because the prognosis of mucinous cystadenocarcinoma is better than that of the usual pancreatic cancer, even though the tumor shows a communication with neighboring organs.

[Painful muscle cramps in liver cirrhosis and effects of oral taurine administration]

We administered 3 g of taurine orally for four weeks to 35 patients suffering from liver cirrhosis with repeated muscle cramp (MC). Improvement of MC was noted in 22 cases (62.9%). We also determined the plasma taurine concentration in eight cases of liver cirrhosis with MC. The plasma taurine concentration before ingestion was 54.1 +/- 20.7 nmol/ml, whereas that of four weeks after ingestion was 125.1 +/- 59.1 nmol/ml, which was significantly elevated by 2.3 fold. As the concentration increased, the frequency of MC decreased, suggesting the good correlation between ingestion and the decrease in frequency of MC. In liver cirrhosis without MC the plasma taurine concentration was 81.0 +/- 16.7 nmol/ml, which was significantly higher than in liver cirrhosis with MC. In a few cases with taurine ingestion, serial plasma taurine concentrations were detected. Plasma taurine reached the peak value during the first week of ingestion and plasma taurine levels were maintained 2-5 fold higher during ingestion.

Studies on dental high-speed cutting with carbide burs used on bovine dentin

Bovine dentin was cut by hand with carbide burs and two cutting procedures while the rotational handpiece speed and the applied load were simultaneously monitored. It became evident that the maximum applied load during intermittent cutting varied from approximately 30 to 40 gm, whereas that during successive cutting ranged from approximately 20 to 60 gm. It showed that intermittent cutting produced a greater cutting effectiveness (for example, cutting volume per cut contact time) when carbide burs were used on dentin, compared with continuous cutting. It is recommended that the intermittent cutting procedure be used during work on patients.

Analysis of discordant test results among five second-generation assays for anti-hepatitis C virus antibodies also tested by polymerase chain reaction-RNA assay and other laboratory and clinical tests for hepatitis

The diagnostic performances of five commercially available second-generation assays for anti-hepatitis C virus antibody, two enzyme-linked immunosorbent assays, one enzyme immunoassay, and two particle agglutination assays (passive hemagglutination assay and particle agglutination assay), were evaluated. Among 104 samples from healthy subjects and 300 consecutive samples from patient ordered for routine determinations of anti-hepatitis C virus antibody in serum, assay results showed variable degrees of discordance for 17 samples (4.2%). These 17 samples were further tested by an immunoblot assay, the polymerase chain reaction-RNA assay, and the hemagglutination inhibition assay. Four of the 17 samples were regarded as true positive, since all supplementary assays and clinical data indicated active hepatitis C virus infection. Another five samples were considered false positive because no confirmatory evidence was obtained from the laboratory analysis or clinical data. The remaining eight samples were negative for hepatitis C virus RNA, but the results of the other supplementary tests were indeterminate. Some of these samples with indeterminate results may have been from patients with subclinical cases of disease who spontaneously recovered from hepatitis with persistent anti-hepatitis C virus antibody in their sera.

Novel 5-HT3 antagonists. Isoquinolinones and 3-aryl-2-pyridones

Synthesis and pharmacological evaluation of a series of 1,2-dihydro-1-[(5-methyl-1-imidazol-4-yl)methyl]-2-oxopyridine 5-HT3 antagonists are described. The key pharmacophoric elements were defined as a basic nitrogen, a linking group capable of hydrogen bonding interactions, and an aromatic moiety. 1,2-Dihydro-2-oxopyridine moiety could be a good linking group because of its nicely planar structure. The steric limitations of the aromatic moiety were investigated by X-ray analysis and computer analysis and shown to be optimal when the aromatic moiety was constrained within an arched planar system, which could be successfully replaced by 3-(2-thienyl)-2-oxopyridine function or 6-amino-7-chloro-1-isoquinolinone function without any loss of the activity. Among the synthesized compounds, 42 showed the most potent activity in the inhibition of Bezold-Jarisch reflex in rats. Compounds 44a and 64 were orally active in the protection against cisplatin-induced emesis in dogs or ferrets. Structure-activity relationships are discussed.

[Clinical significance of thrombin-antithrombin III complex and plasmin-alpha 2 plasmin inhibitor complex in chronic liver diseases]

Thrombin-antithrombin III complex (TAT) and Plasmin-alpha 2 plasmin inhibitor complex (PIC) were examined in fifty two cases of various chronic liver diseases. TAT was significantly elevated in cases of hepatocellular carcinoma (HCC), but PIC did not show significant changes in any chronic liver diseases. Elevations of TAT and PIC were seen in cases of HCC accompanied by tumor enlargement and extensive tumor thrombosis. In cases of HCC undergoing transcatheter arterial embolization (TAE), TAT and PIC increased on the next day after TAE, and tended to recover with time, returning to almost normal at fourth week. Prolongation of prothrombin time, elevation of FDP and positive FM test were noted more often in liver cirrhosis with disseminated intravascular coagulation (DIC) than in severe liver dysfunction without DIC. Of five cases confirmed as DIC, only three cases were diagnosed as DIC by DIC score. On the other hand, TAT and PIC were significantly elevated in DIC cases. Especially, TAT exceeded 30 ng/ml in all DIC cases. TAT was regarded to be useful for the diagnosis of DIC in severe liver dysfunction.