Characteristics of hepatocellular carcinoma in patients with negative virus markers: clinicopathologic study of resected tumors

Fifty-one cases of resected hepatocellular carcinoma (HCC) were retrospectively analyzed to evaluate the clinicopathologic features of HCC in patients with negative virus markers. The data were compared between three groups: hepatitis B surface antigen positive (HB, n = 11), hepatitis C virus antibody positive (HC, n = 21), and non-BC (both HbsAg and HCVAb negative, n = 12). Seven patients were excluded from the study because of operative death (n = 3), a history of alcohol abuse (n = 3), or the presence of dual positive HB and HC virus markers (n = 1). The data were analyzed by either an analysis of variance (ANOVA) or a contingency table. The age of the non-BC patients was higher (63.0 +/- 4.1, +/- SE) than that of HB patients (54.0 +/- 3.2, p < 0.05) but was identical to that of the HC group (62.0 +/- 1.8). Among the preoperative laboratory data, the serum glutamic oxaloacetate and glutamate pyruvate transaminoses (GOT, GPT) levels were statistically lower in the non-BC patients (32.8 +/- 4.8 and 28.0 +/- 4.4 IU/L, respectively) than in the HB and HC patients. The pathologic features of the resected specimens in the non-BC patients showed more invasive growth than in specimens from the HB or HC patients. The clinical stages (defined based on the criteria of the Japanese Association of Hepatocellular Carcinoma) were also more advanced in the non-BC patients than in the other groups. Postoperative survival time showed no significant difference among the groups. In conclusion, the non-BC patients had comparatively greater invasive growth and more advanced clinical stages than the HB and HC patients, despite the absence of liver cirrhosis, and so demonstrated the same poor survival data as observed in the HB and HC patients.

A proposed optimal health care system based on a comparative study conducted between Canada and Japan

OBJECTIVES

Every country wants a good health care system for all citizens with minimum expenditure. By comparing health care systems in Canada and Japan, both of which have a universal health care system for all citizens in its own country, an attempt was made to visualize or search for an optimal health care system.

METHOD

Data and information obtained were tabulated and compared from the standpoint of the effectiveness of the health insurance system and the feasibility of its application so as to propose an optimal health care system.

RESULTS AND CONCLUSIONS

Some of the suggestions and proposals made for an optimal health care system for all citizens include implementation and/or establishment of minimal user fees, centralized rational decision-making processes, private delivery system of health care, centralized computer-aided patient record system, insurance monitoring system, patient education, and physician guidelines.

[Genetic alterations in human malignant tumor]

To clarify the genetic background of cancer patients, microsatellite instability (MSI) and mutations of transforming growth factor-beta type II receptor (RII), p53 and k-ras gene were investigated. MSI were detected in 33.3% of esophageal, 15.8% of gastric, 21.4% of colorectal, 4.5% of bile duct, 0% of gallbladder, 13.3% of pancreatic, 11.6% of breast and 10.5% of thyroid cancers. Mutations of RII gene were detected in only 2 of 9 MSI-positive colorectal cancers. k-ras gene mutations were investigated in colorectal, bile duct, gallbladder, breast and thyroid cancer and were detected in 11.9%, 36.4%, 64.3%, 0%, 0% of each. p53 gene mutations were investigated in colorectal and breast cancer and were detected in 9.5% and 9.3%, respectively. In addition, 4 colorectal cancer cases exhibited more than two kinds of genetic alteration, while breast cancer cases showed only single kind. From these findings, it is suggested that 1) the incidence of each genetic alteration differed among the cancers investigated and organ specificity may exist; 2) the genetic alterations investigated here contributed to a minor part of cancer development, which requires the identification of more unknown genes related to carcinogenesis; 3) to clarify the molecular mechanism of cancer development, the genetic alterations including genomic instability and mutations of several kinds of genes related to cancer development in each case should also be determined along with their genetic molecular profile.

Preparation of a conjugate of mitomycin C and anti-neural cell adhesion molecule monoclonal antibody for specific chemotherapy against biliary tract carcinoma

To develop a specific chemotherapy modality for the perineural invasion of neural cell adhesion molecule (NCAM) positive biliary tract cancer, an anticancer drug, mitomycin C (MMC), was covalently bound to anti-NCAM monoclonal antibody (anti-NCAM MoAb) to form a conjugate using the cyanogen bromide method. The substitution ratio of the conjugate determined spectrophotometrically was 3.5 (MMC mol/immunoglobulin G mol). The cytotoxic activity of the conjugate, which was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test in the growth inhibition of the neuroblastoma cell line with NCAM expression, was maintained at 65.8% to 94.5% compared with the same concentration of MMC solution. The binding activity of the conjugate to the NCAM-positive bile duct cancer was examined by immunohistochemical staining and proved to be the same level as that of free anti-NCAM MoAb. The conjugate prepared in this study therefore appeared to be a potentially useful tool for immunotargeting specific chemotherapy against biliary tract cancer with NCAM expression.

Revision of ventriculo-peritoneal shunt under laparoscopic guidance in patients with hydrocephalus

Ventriculo-peritoneal (V-P) shunt is a common treatment for hydrocephalus. However, shunt insufficiency due to obstruction, dislocation, and detachment of the peritoneal tube is frequently encountered. We designed a new technique in which the peritoneal tube is inserted into a target site of the abdominal cavity under laparoscopic guidance. We operated on 9 patients with hydrocephalus using this technique. Shunt insufficiency of the peritoneal tube had been observed in all patients, and 7 patients had undergone repeated revision of the peritoneal tube before this procedure. Our laparoscopic-assisted method ensured tube insertion into the appropriate site, and minimized the abdominal wound and postoperative adhesions. This method also made it possible to differentiate abdominal pain induced by shunt failure from pain caused by other diseases, including appendicitis. In conclusion, we consider this new technique for V-P shunt performed under laparoscopic guidance to be very useful.

Perforation due to metastatic tumors of the ileocecal region

We reviewed our department's medical records between April 1986 and April 1994 to identify patients who showed acute abdominal symptoms requiring surgical treatment due to metastatic tumors of the small intestine. In group A, seven patients (30%) were treated for acute peritonitis, and all were found to have an intestinal perforation due to hematogenous metastases (group A). In group B, 16 patients (70%) were treated for an intestinal obstruction, and all were found to have disseminated tumors of the small intestine (group B). In group A all tumors were isolated and located exclusively in the ileocecal region, whereas all tumors in group B showed peritoneal dissemination, with no predominant anatomic localization. In general, the intestinal tumors in group A originated from cancers of the upper aerodigestive tract, whereas those in group B originated from advanced cancers in the abdominal cavity. The tumors were significantly smaller and the period between the onset of symptoms from the original malignancy and the onset of abdominal symptoms (perforation or obstruction) was significantly shorter in group A. In conclusion, intestinal metastases located in the ileocecal region have unique clinicopathologic features and so should be recognized as a distinct disease entity. Therefore when patients with a known upper aerodigestive malignancy exhibit acute abdominal symptoms, intestinal metastasis to the ileocecal region, necrotic changes, and perforation should be considered in the differential diagnosis.

Combined hepatocellular and cholangiocellular carcinoma in a non-cirrhotic liver

Combined hepatocellular (HCC) and cholangiocellular carcinoma (CCC) (mixed carcinoma) is a rare subtype of primary hepatic carcinoma. We report a case of mixed carcinoma that developed in a non-cirrhotic liver, in a patient who was serologically negative for both hepatitis B and C viruses. A 65-year-old Japanese woman with a 25-year history of chronic rheumatoid arthritis had been treated with steroids and anti-inflammatory drugs, and was diagnosed by ultrasonography with an asymptomatic solitary tumor in the right lobe of the liver. On computed tomography scan and hepatic arteriography, the tumor was well enhanced by contrast medium in the early phase. Based on the findings of elevated serum alpha-feto protein (AFP, 245 ng/ml) and normal carcino-embryonic antigen (CEA, 2.6 ng/ml) levels, a preoperative diagnosis of hepatocellular carcinoma was made. Right lobectomy of the liver was performed on January 7, 1997. Histological examination showed that the resected tumor consisted of combined CCC cells and HCC cells in an intermingled form, with CCC being far more dominant than HCC. The tumor was therefore determined to be a combined carcinoma, subclassified as intermingled type. This case appears to indicate that mixed type carcinoma developed in a non-cirrhotic liver, with CCC being dominant; such a finding is extremely unusual, based on previously published reports.

Two-step portal bypass to reconstruct an invaded superior mesenteric vein in pancreatic cancer

Advanced cancer of the pancreatic head, especially in its caudal portion, has a limited surgical resectability due to its frequent invasion to the superior mesenteric vein (SMV). A patient with advanced carcinoma of the pancreatic head with vascular invasion to the major bifurcation of the SMV, underwent a pancreatico-duodenectomy under a two-step passive bypass of the portal flow. The marginal colic veins were dilated and formed a long collateral route to the inferior mesenteric vein and the splenic vein due to stenosis of the SMV. The venous flow in this vein was then easily interrupted with the surgical manipulation of the transverse colon. The first passive bypass was thus inserted into the accessory right colic vein to preserve the venous return from both the small intestine and the colon, and also to enable surgical dissection of the invaded SMV itself. After a thorough dissection of the invaded SMV, a second bypass was inserted into the main trunk of the SMV through the dissected vascular stump. Subsequently the passive bypass was maintained until the portal reconstruction with an interposition of the left common iliac vein could be performed. The patient recovered well from the surgery without any complications throughout the postoperative course. In summary, the two-step portal bypass describes, is thus considered a stable and safe procedure for the reconstruction of the superior mesenteric vein, during pancreatoduodenectomy for advanced carcinoma of the pancreatic head.

Radiation enterocolitis: overview of the past 15 years

From April 1980 to April 1995 a total of 54 patients (53 women, 1 man) were hospitalized in our department for the surgical treatment of radiation enterocolitis. Two surgical protocols were applied for these patients: intestinal decompression procedures alone (intestinal bypass, colostomy, or both; n = 18) or an intestinal resection in addition to decompression (n = 36). The clinical factors contributing to survival after irradiation were retrospectively reviewed by a multiple variate proportional hazards model. As a result, patients treated with decompression procedures alone had an 11 times higher risk for death than those treated with the addition of intestinal resection. In the former group, 5 of 18 patients died of bleeding from the remaining intestine after operation. We concluded that surgical resection of the diseased intestine is a useful procedure for treating radiation enterocolitis to reduce intestinal bleeding from the irradiated intestine.

Successful gene transfer to the porcine liver in vivo with an adenoviral vector

In vivo gene transfer to the porcine liver was tested with adenoviral vector to achieve molecular biological graft modulation. In adult female pigs immunosuppressed with cyclophosphamide, cyclosporine, and prednisolone, the liver was surgically isolated and flushed out with cold lactate Ringer solution (4 degrees C), by means of a pump-controlled bypass of the portal vein and the inferior vena cava in Groups A and D. In Group A (n = 4), 2 x 1011 pfu of the adenoviral vectors (pAdexCALacZ) were injected through the left hepatic artery during cold ischemia. In Group (n = 4), 2 x 1011 pfu of adenovirus vectors were injected through the auricular vein in a one-shot manner without a laparotomy. In Group C (n = 4), 2 x 1011 pfu/ml of adenoviral vectors were injected through the hepatic artery in a one-shot manner, without a surgical isolation of the liver. Group D (n = 4) animals received the same protocol as Group A except for the fact that they did not receive the immunosuppressive regimen. In a polymerase chain reaction, a transfected LacZ sequence was detected until POD 28 in Group A, but not in the other groups. In 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) staining, only the Group A animals revealed apparent staining predominantly in the portal area at POD 2, which then continued to be recognized until POD 28. The in situ perfusion of the liver combined with immunosuppression is thought to provide an ideal environment for the liver-directed adenovirus-mediated gene transfer to the porcine liver, by enabling a long contact with a high titer of the adenoviral vector.

Surgical treatment for proximal bile duct carcinoma

BACKGROUND

The surgical management of proximal bile duct carcinoma is controversial. There is no consensus among surgeons as to the indications for radical resection. This article described personal experience with the different surgical procedures for patients with proximal bile duct carcinoma.

METHODS

The medical records of fifty-two consecutive patients undergoing surgical resection over a 20-year period were retrospectively analysed in terms of pathology, perioperative mortality, clinical course, and overall survival.

RESULTS

The 1-, 3- and 5-year survivals for the entire group were 63.3%, 24.5%, and 21.0%, respectively. The results for local resection of the extrahepatic bile duct in 35 cases were unsatisfactory. Radical resection that included the right extended hepatic lobe, caudate lobe, and extrahepatic bile duct was performed in 9 patients and demonstrated an excellent 5 year survival rate of 44.4%. However, hospital mortality was 22.2%. There was no significant difference among the operative procedures for patients with advanced disease.

CONCLUSION

Radical resection remains the procedure of choice in proximal bile duct carcinoma. However, results with surgical therapy alone remain unsatisfactory. Multimodality treatment that also includes radiotherapy and/or chemotherapy is recommended.

Morphologic and mucin histochemical analysis of transitional zones in advanced ulcerated colorectal carcinomas: potential prognostic indicators

BACKGROUND AND OBJECTIVES

The transitional zone, which is normal-appearing mucosa that surrounds a primary colorectal carcinoma, has characteristic histologic features, and an increased amount of sialomucin in the transitional zone have been associated with a poorer prognosis. To clarify the prognostic effects of changes in the transitional zone we studied the transitional zone in cancers of the colon and rectum.

METHODS

A total of 105 specimens resected for advanced colorectal carcinoma were studied to identify the effectiveness of evaluating morphologic types (polypoid or nonpolypoid growth type) and mucin expression (sulfomucin or sialomucin type) of the transitional zone as a prognostic indicator.

RESULTS AND CONCLUSIONS

Nonpolypoid carcinomas were likely to have invaded the deeper layers and lymphatic vessels and go on to develop advanced disease. Sulfomucin-type tumors were predominantly found in the right side colon and followed a relatively favorable course. Our results indicate that the morphologic and mucin components of the transitional zone may be prognostic indicators for advanced colorectal carcinoma.

Molecular cloning and partial characterization of a tobacco cDNA encoding a small bZIP protein

Here we report the isolation of a tobacco cDNA which is a counterpart gene of rice low-temperature-induced lip19. Expression of the gene (termed tbz17) is also positively controlled by low temperature but fairly moderately compared with the low-temperature-responsiveness of rice lip19 and the maize counterpart gene, mlip15. The predicted gene product (termed TBZ17) is a bZIP protein of 145 amino acids and shows about 45% identity with rice LIP19 and maize mLIP15 proteins. DNA binding studies indicate that TBZ17 has quite similar DNA binding characteristics to that of mLIP15. The results suggest that low-temperature-induced gene(s) encoding a DNA binding factor with bZIP motif is omni-present in higher plants.

Two maize genes encoding omega-3 fatty acid desaturase and their differential expression to temperature

We have isolated two maize cDNAs and the corresponding genes encoding fatty acid desaturase with Arabidopsis thaliana FAD7 gene as a probe. They shared almost 90% identity at DNA sequence level. Northern analysis revealed that both genes are expressed in leaves, but not in roots at normal temperature- and low temperature-growth condition. The overall level of these transcripts are elevated upon exposure to low temperature. The tissue-specific expression and DNA sequence data indicate that both genes encode plastidic omega-3 fatty acid desaturases. One of them is expressed exclusively at normal temperature but not at 5 degrees C, whereas the other is expressed inversely. We, therefore, termed them ZmFAD7 and ZmFAD8, respectively. Among other stresses, high-salt treatment induced the accumulation of the ZmFAD7 and ZmFAD8 transcripts in roots but drought had no effect on their expression. Cycloheximide induced the accumulation of the ZmFAD7 transcript in roots. The genomic clones of ZmFAD7 and ZmFAD8 consist of 8 exons and 7 introns as same as in the cases of A. thaliana FAD7 and FAD8 genes and the sizes of the 6 internal exons were identical among them. A phylogenetic analysis of ZmFAD7, ZmFAD8 amino acid sequences and those originated from other plant species is also presented.

Clinicopathologic features of resected primary adenosquamous carcinomas of the liver

Four cases of resected adenosquamous carcinoma of the liver were clinicopathologically reviewed, together with immunohistochemical findings. Although no lymph node metastases were seen and a curative resection was achieved in all cases, two patients had recurrences in the peritoneum and distant organs such as the pericardium and pleura relatively soon after the operation. Of the remaining two cases, one patient died during the postoperative period and the other died of coexistent hilar cholangiocarcinoma. Together these findings suggest that this disease tends to spread locally and distantly in the early phase of tumor growth and shows aggressive biological behavior. In an immunohistochemical study, involucrin was a specific marker for the squamous component and CA19-9 was a marker for the adenomatous component.

Expression of the Escherichia coli bo-type ubiquinol oxidase with a chimeric subunit II having the CuA-cytochrome c domain from the thermophilic Bacillus caa3-type cytochrome c oxidase

The C-terminal periplasmic domain of subunit II of the Escherichia coli bo-type ubiquinol oxidase was replaced with the counterpart of the thermophilic Bacillus caa3-type cytochrome c oxidase containing the CuA-cytochrome c domain by means of gene engineering techniques. The chimeric terminal oxidase was expressed by a pBR322 derivative in a terminal oxidase deficient mutant of E. coli, although the amount of the chimeric enzyme was smaller than that of the Escherichia coli bo-type ubiquinol oxidase expressed by the original cytochrome bo-expressing plasmid. The chimeric enzyme showed much higher TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine) oxidase activity than the wild-type cytochrome bo, but lower activity than the thermophilic Bacillus caa3-type cytochrome c oxidase. The chimeric subunit II was confirmed to bind to heme C. These results suggest that the CuA-cytochrome c domain grafted to this membrane anchor can facilitate electron transfer from reduced TMPD to low-spin protoheme b in subunit I.

Overcoming CPT-11 resistance by using a biscoclaurine alkaloid, cepharanthine, to modulate plasma trans-membrane potential

Irinotecan, 7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin, (CPT-11) resistance was overcome by using a biscoclaurine alkaloid, cepharanthine, in CPT-11- and multidrug-resistant 50MT-1 cells. 50MT-1 cells were established from a mouse breast-cancer cell line, FM3A, by subjecting the cells to a low dose of CPT-11 continuously. 50MT-1 cells exhibited resistance to CPT-11 (40-fold in colony-formation assay) and to other drugs such as doxorubicin (11.7-fold) and etoposide (VP-16) (16.8-fold). The plasma trans-membrane potential was lower in 50MT-1 cells than in FM3A cells, although there were no differences in expressions of P-glycoprotein and of DNA topoisomerase-I and -II proteins. The lower membrane potential in 50MT-1 cells was augmented by co-treatment with a non-toxic dose of cepharanthine. CPT-11 resistance in 50MT-1 cells was overcome (5.0- to 1.4-fold, 6-hr exposure) by the co-treatment with cepharanthine through increasing intracellular accumulation of CPT-11. Resistance to doxorubicin and VP-16 was also overcome by cepharanthine treatment (2.5- to 0.69-fold and 4.2- to 1.4-fold respectively). We conclude that the modification of plasma trans-membrane potential by cepharanthine should be effective in overcoming CPT-11 and multidrug resistance in 50MT-1 cells.

Esophageal cancer in patients with head and neck cancers

Nine male patients with separate primary cancers of the esophagus and head and neck (pharynx, larynx) presented with a mean age of 56 years (41-69). They included 7 pharyngeal cancer patients and 2 laryngeal ones. Esophageal cancer was discovered synchronously in 6 patients and metachronously in 3 (1, 4, and 11 years later, respectively). The head and neck cancer was stage-I in one patient, stage-II in 4 and stage-IV in 4. The esophageal cancer was cervical in 2, thoracic in 6 and abdominal in 1. It was early cancer (stage-0) in 6 patients and advanced (stage-IV) in 3. The esophageal cancer was more advanced in the metachronous group, while it was early in the synchronous group. Since the head and neck cancer was advanced, all patients underwent a total laryngectomy for their head and neck cancers. As for esophageal surgery, a transhiatal esophagectomy was, in principle, performed for early cancers while a total thoracic esophagectomy was done for advanced cancers. For the reconstruction of the esophagus, a gastric tube was used. Four patients are still alive with a mean survival time of 25 months, whereas five died of cancer recurrence of either type a mean of 19 months after surgery. As compared with the survival rates of the patients with esophageal cancer alone, the 5-year survival rate was 18.2% for patients with double cancers in this series and 27.9% for those with esophageal cancer alone.

Involvement of endothelin in graft-versus-host disease after rat small bowel transplantation

Endothelin (ET-1) expression was evaluated by radioimmunoassay in both plasma and various tissue specimens serially obtained from LBN-F1 recipients of LEW heterotopic small bowel allografts. The recipients showed graft-versus-host disease (GVHD), which histologically became apparent on postoperative day (POD) 13. The ET-1 levels peaked on POD 9 in the kidney, lung, and host intestine at 51.0 +/- 21.1, 90.9 +/- 59.6, and 25.4 +/- 11.8 pg/g wet, respectively, and peaked on POD 11 in the plasma at 7.7 +/- 3.2 pg/ml; thereafter, they decreased to basal levels in both the plasma and tissue specimens on POD 13. An immunohistochemical study of these organs showed a corresponding increase in ET-1 staining in both the endothelial and epithelial cells on PODs 5 and 9, and a reduction in staining on POD 13. In conclusion, ET-1 was found to be increasingly released from the target cells of GVHD before any histological changes became apparent, thus suggesting the pathophysiological involvement of ET-1 in intestinal GVHD.

Thoracoscopic thoracic splanchnicectomy for chronic pancreatitis with intractable abdominal pain

The therapeutic advantages of a thoracoscopic thoracic splanchnicectomy (TTS) to relieve the pain of chronic pancreatitis patients was evaluated. The TTS procedure (four bilateral and five unilateral TTS), was performed on nine patients from April 1993 to October 1995. Based on radiographic images, the pancreatic duct of seven cases were diagnosed as being "nondilated" (<3 mm), whereas two cases were "dilated" (> or = 3 mm). A 5-mm thoracoscope was introduced through the fifth intercostal space on the anterior axillary line, and an additional two cannulas were introduced under direct thoracoscopic vision. The sympathetic chain, at a level from Th 5 to 9, was then resected and electrocoagulated. We performed a unilateral TTS corresponding to the symptomatic side; however, if pain relief was insufficient, an additional sympathectomy was done on the other side. The early postoperative course was uneventful, and immediate pain-relief was normally possible after TTS except for three patients who demonstrated minor intercostal neuralgia at the site of the trocars inserted for TTS. Six of nine patients were able to return to their preoperative work of lifestyle at a maximum follow-up of 24 months (the median and mean durations were 15.0 and 13.7 months, respectively). In addition, no postoperative deterioration of either the endocrine or exocrine function of the pancreas was observed. In conclusion, TTS proved to be a safe and reliable procedure for the pain relief of the chronic pancreatitis.

Villous adenoma of the gallbladder: a case report

A 76-year-old female with villous adenoma of the gallbladder is herein reported. She presented complaining of upper abdominal pain for some months prior to admission. No tumor mass could be detected by transabdominal ultrasonography, but CT scan demonstrated a sessile tumor measuring some 2 cm in diameter. A simple cholecystectomy was thus performed. The resected gallbladder was filled with mucinous material, and showed a sessile tumor with finger-like processes in the fundus. Both the macro- and microscopical findings of the lesion were almost identical to a typical villous adenoma of the colon. Little information is available on villous adenoma of the gallbladder, because such cases are extremely rare. In this paper, is described e a rare villous adenoma lesion while paying special attention to the morphological findings.

Role of exogenous L-arginine in hepatic ischemia-reperfusion injury

Plasma L-arginine is usually deficient immediately after hepatic reperfusion in orthotopic liver transplantation, which may also contribute to the occurrence of either hepatic ischemia-reperfusion injury or pulmonary hypertension. In this study, exogenous L-arginine was thus experimentally used to reverse the deficient status of the L-arginine/NO pathway. An in vivo model of 1 hr hepatic ischemia and reperfusion was thus tested in both rats (Experiment A) and pigs (Experiment B). In Experiment A, 10 mg/kg of L-arginine (group 1, n = 7), D-arginine (group 2, n = 7), or saline (group 3, n = 7) was administered through the portal vein. The hepatic tissue blood flow, at 20 min after reperfusion, improved in group 1 (70.7 +/- 7.0% of the preclamp levels) compared to groups 2 and 3. The serum glutamate oxaloacetate transaminase levels at 24 hr after reperfusion were also lower in group 1 (320 +/- 22.2 IU/L) than in either group 2 or group 3. The intrahepatic NO levels showed a temporal burst (> 15,000 pA current) after reperfusion only in group 1. In Experiment B, 10 mg/kg of L-arginine (group 4, n = 5), D-arginine (group 5, n = 5), or 10 ml of saline (group 6, n = 5) was administered through the portal vein. In group 4, the MPAP (mean pulmonary arterial pressure)/MAP (mean arterial pressure) was lower than that observed in groups 5 and 6. In conclusion, exogenous L-arginine administered from the portal vein was thus found to be effective in mitigating both portal hypertension and reperfusion injury by producing an increased amount of NO immediately after reperfusion.

Cycloheximide induces a subset of low temperature-inducible genes in maize

To investigate further the signal transduction pathway that mediates the cold-stress response in maize, we isolated a low temperature-inducible cDNA clone (ZmCDPK1) that encodes a calcium-dependent protein kinase. Time-course experiments revealed that the low-temperature induction of ZmCDPK1 precedes that of mlip15, another cold-inducible gene that codes for a DNA-binding protein of the basic region/leucine zipper (bZIP) type, indicating that ZmCDPK1 might be located upstream of mlip15 in the cold-stress signal transduction pathway. We observed that the steady-state mRNA level of mlip15 drastically increased after cycloheximide treatment. In addition to mlip15, cycloheximide elevates the transcript levels of two other low temperature-induced genes, ZmCDPK1, and Adh1, which encodes alcohol dehydrogenase 1. In contrast, the chalcone synthase gene was only inducible by low temperature. The accumulation of the mlip15 transcript at low temperatures and in response to cycloheximide was significantly reduced by pretreatment with a calcium chelator, suggesting that calcium is involved in both cases of mlip15 induction. The signal transduction pathways triggered by low temperature and cycloheximide are discussed in relation to these observations.

Vascular reconstruction for intraoperative major vascular injuries

BACKGROUND

The purpose of this study was to find an effective and precise surgical procedure to cope with the major vascular injuries that might be encountered during hepato-biliary and pancreatic surgery.

MATERIALS AND METHODS

Among the 220 cases of hepato-biliary and pancreatic surgery from 1991 to 1995 in our department, 8 patients who sustained 13 different instances of vascular injury were reviewed retrospectively.

RESULTS

Five injuries occurred in the portal vein (PV), 4 in the hepatic artery (HA), and 2 in the inferior vena cava (IVC). The repair procedures consisted of 2 direct closures, 2 resections of the injured sites followed by the end to end anastomosis, 2 autologous venous grafts and 1 artificial vascular graft implantation, and 2 diversions of the arterial bloodflow of the middle colic artery and the gastroepiploic artery to the injured HA. The reconstructed vessels showed postoperative obstructions in 2 cases, in which artificial vascular graft implantation and direct closure were used for the reconstruction.

CONCLUSIONS

Based on the above findings, the use of an artificial graft and a direct closure all contributed to the early postoperative obstruction of the reconstructed vessels. However, a diversion of the arterial bloodflow to the injured hepatic arteries was found to maintain a good postoperative patency in these cases.

[Responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 after esophageal cancer operation]

Studies on responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 (TXB2) were carried out with 18 esophageal cancer patients who had undergone radical esophagectomy through right thoracotomy and reconstruction with gastric tube. Plasma levels were measured for the following for coagulation assessment: thrombin.antithrombin III complex (TAT), soluble fibrin monomer complex(SFMC), fibrinogen, antithrombin III, protein C and thrombomodulin. Selected fibrinolytic markers are: tissue plasminogen activator.plasminogen activator inhibitor 1 complex (tPA.PAI1C), plasminogen, alpha 2 plasmin inhibitor, plasmin. alpha 2 plasmin inhibitor complex(PIC), FDP and D-dimer. Peripheral venous blood samples were taken from the patients before the operation, immediately after the operation and on each of the first, second, third, seventh and fourteenth day after the operation. It was observed that TAT, SFMC, tPA.PAI-1C and TXB2 were remarkably altered immediately after the operation. This indicates that the major surgical stress significantly activated coagulation, fibrinolysis and platelets. Higher plasma levels of TAT compared to the pre-operation level was recorded for two weeks after the operation. Furthermore, in four cases, SFMC became positive during three to seven days after operation. These facts indicate that the activation of coagulation persisted during the days after operation. PIC began to increase from the 2nd to 3rd days after operation, reaching the maximum on the 7th day. Biphasic changes which peaked twice on the 1st and 7th days after operation were shown in plasma levels of FDP and D-dimer. These results indicate that the activation of fibrinolysis also persisted during the days after operation. The activation of coagulation and fibrinolysis may persist at least for two weeks after major surgical operation. Careful observation for the states of these systems was thought to be needed during the post-operative days, and the molecular markers could be useful to assess subclinical changes of these systems.

Antioxidative activity of barley hordein and its loss by deamidation

Barley hordein was comparable to maize zein in antioxidation under a powder model system. Various deamidated "hordein" preparations were obtained and examined for their molecular-size distribution (by Sephacryl S-100 gel filtration), hydrophobicity (by fluorescence measurement using fluorescent probes) and antioxidative activity (by the ferric thiocyanate method). Deamidation caused fragmentation of the hordein molecule and simultaneously lowered its fatty acid-binding capacity rather than its surface hydrophobicity. Then, the antioxidative activity diminished with increasing deamidation. When the fatty acid-binding capacity was plotted against the antioxidative activity, a high correlation (r2 = 0.92) was observed between these two events.

Pulmonary endocrine cell hyperplasia and papilloma in rats induced by intratracheal injections of extract from particulate air pollutants

We investigated the effect of intratracheal injections of an extract of suspended particulate matter (SPM) obtained from the urban ambient air of Tokyo, upon the development of proliferative lesions of pulmonary endocrine cells (PECs) in the rat. We also examined the modification effects of nitrogen dioxide, sulfur dioxide, or both of them on the PEC lesions. Male F344 rats were divided into six experimental groups of 5 animals each. Twenty animals were treated with intratracheal instillations of SPM admixed with carbon once a week for 4 weeks with or without additional gaseous exposure (6 ppm nitrogen dioxide or 4 ppm sulfur dioxide) 16 hrs a day for 11 months. Five animals were given intratracheal injections of carbon suspended in saline and the other five were untreated. The subcardiac lobes of the right lung were fixed with 4% paraformaldehyde, and embedded in paraffin. PEC hyperplasias and papillomas were counted in 200 serial sections, 4 microns thick. The average incidences of PEC hyperplasia in the untreated animals and in those treated with carbon were 194 and 200/cm3, respectively. The average incidences of PEC hyperplasia in the animals exposed to SPM tar only, SPM tar plus nitrogen dioxide and sulfur dioxide, SPM tar with nitrogen dioxide and SPM tar with sulfur dioxide were 376, 378, 372 and 349/cm3, respectively. These were significantly higher than the levels of the control animals, and additional gaseous stimuli had no effect on the incidence of PEC hyperplasia. Besides PEC hyperplasia, a few PEC papillomas were found in the animals treated with SPM tar, regardless of gaseous exposure, but in the control animals no papilloma was evident. Thus, compounds in airborne particulates are considered to be responsible for the development of PEC hyperplasias and papillomas.

The use of intraoperative ultrasonography for detecting tumor extension in bile duct carcinoma

The purpose of this study was to investigate the clinical feasibility of using intraoperative ultrasonography (IOUS) to detect tumor extension in bile duct carcinoma, especially longitudinal invasion along the bile ducts into either the hepatic parenchyma or adjacent hilar vessels.

MATERIALS AND METHODS

The medical records of 14 patients with bile duct carcinoma who underwent surgical treatment at the First Department of Surgery, University of the Ryukyus, were retrospectively analyzed. All patients were examined by IOUS during the operation. The resected specimens were processed in order to compare the ultrasound images with the histological findings.

RESULTS

The echo level of the primary lesion was not consistent. Specific echo patterns, such as a thickening of the echogenic layer (TEL) adjacent to the main tumor showing cancerous invasion, were observed in ten patients, 71.4% (nodular invasive 7, invasive 3) which were later confirmed by microscopic examinations and ultrasonic findings. The detection rate of TEL was 87.5% in nodular invasive type and 100% in invasive type, respectively. The TEL histologically coincided with a layer of fibrotic hypertrophy around the infiltrating tumor cells. The intramural invasion beyond the edge of TEL was detected in only 2 out of 11 patients. The accurate detection rate of the involvement of the portal vein and the hepatic artery by IOUS was 83.3% and 60%, respectively. Based on the above findings, IOUS is thus considered to be essential for evaluating tumor extension along the bile ducts, and also greatly helps in selection of the most appropriate operative procedure, especially in hilar cholangiocarcinoma.

Adenovirus-mediated gene transfer using in-situ perfusion of the liver graft

To establish an efficient technique for adenovirus-mediated gene transfer in liver transplantation, we evaluated the in situ perfusion of liver grafts. The grafts were perfused in situ with 1 x 10(10) of E1-deleted, replication-defective adenoviral vectors encoding the LacZ gene driven by the human CMV promoter, either through the hepatic artery (group 1) or the portal vein (group 2). Group 3 animals served as negative controls; their liver grafts were perfused with lactated Ringer's solution through the portal vein. PCR confirmed the presence of viral DNA in every graft perfused with viral vectors. In X-gal staining, positive staining was observed almost exclusively at the portal triad in group 1, whereas in group 2 minimal staining was observed, predominantly in the parenchymal area. Protein production from the transfected gene was confirmed by a functional protein assay; the values were 0.16% +/- 0.07% liver protein in group 1, 0.13% +/- 0.02% in group 2, and 0.007% +/- 0.0003% in group 3 on postoperative day 2. In conclusion, in situ perfusion of the viral vectors through the hepatic artery resulted in an effective expression of the transfected gene, predominantly at the portal triad.

Involvement of endothelin in graft-versus-host disease after rat small bowel transplantation

Endothelin (ET-1) expression was evaluated by radioimmunoassay in both plasma and various tissue specimens serially obtained from LBN-F1 recipients of LEW heterotopic small bowel allografts. The recipients showed graft-versus-host disease (GVHD), which histologically became apparent on postoperative day (POD) 13. The ET-1 levels peaked on POD 9 in the kidney, lung, and host intestine at 51.0 +/- 21.1, 90.9 +/- 59.6, and 25.4 +/- 11.8 pg/g wet, respectively, and peaked on POD 11 in the plasma at 7.7 +/- 3.2 pg/ml; thereafter, they decreased to basal levels in both the plasma and tissue specimens on POD 13. An immunohistochemical study of these organs showed a corresponding increase in ET-1 staining in both the endothelial and epithelial cells on PODs 5 and 9, and a reduction in staining on POD 13. In conclusion, ET-1 was found to be increasingly released from the target cells of GVHD before any histological changes became apparent, thus suggesting the pathophysiological involvement of ET-1 in intestinal GVHD.

[Clinical efficacy of imipenem/cilastatin sodium for respiratory infections in patients with lung cancer]

Imipenem/cilastatin sodium (IPM/CS) was administered to 102 patients with respiratory tract infections and lung cancer. Patients with other serious diseases were excluded and a total of 73 patients were enrolled. They were divided into 12 patients who underwent surgery (operated group) and 61 who did not (non-operated group); the latter group included 28 patients treated with anticancer agents or radiation therapy (treated group) and 33 untreated patients (untreated group). IPM/CS was effective in 75% of the patients, both with and without surgery. The drug was effective in 81% of the treated group, although many of the patients had Stage III or more advanced cancer, as well as bronchial occlusion. IPM/CS was also effective in 69% of the untreated group, although many of the patients have serious infections and a PS (Performance Status) of 3 or greater. Thus, IPM/CS treatment achieved good results. Bacteriological studies showed that 3 out of 4 strains in the operated group and 16 out of 18 in the non-operated group were eliminated. Safety was evaluated in all patients. Two patients (2%) experienced side effects and two others (2%) showed abnormal clinical findings, but the symptoms were mild and resolved after discontinuation or completion of therapy. In conclusion, IPM/CS was very effective for treating respiratory infections in patients with lung cancer.

The effect of cyclosporin on endothelin levels after orthotopic liver transplantation in rats

To assess the effects of cyclosporin (CyA) on endothelin-1 (ET-1) in rat liver allograft rejection, we evaluated ET-1 expression in samples obtained from BN(RT1n)-to-BN (group 1) rats, DA(RT1a)-to-BN (group 2) rats, and DA-to-BN rats treated with 5 mg/kg per day of CyA (group 3). Serum and hepatic ET-1 levels, determined by a radioimmunoassay, remained unchanged in group 1. In group 2, the ET-1 levels peaked on postoperative day (POD) 5 in the liver at 344 +/- 31.6 pg/g wet, and on POD 7 in the serum at 38.7 +/- 13.1 pg/ml. In group 3, hepatic and renal ET-1 levels showed a progressive increase until POD 10, while serum ET-1 levels remained unchanged. In conclusion, acute rejection caused a temporary increase in the ET-1 level in both the serum and the liver in the early postoperative period what might have been caused by endothelial damage due to ongoing, acute rejection. CyA caused a time-dependent increase in the ET-1 level in both the liver and the kidney without an increase in the serum ET-1 level. The serum ET-1 level might have been affected by the clearance of ET from the liver or kidney.

The production and clearance of endothelin and its influence on kidney function after liver transplantation in rats

To assess the involvement of endothelin-1 (ET-1) in rat liver allograft rejection, we evaluated ET-1 expression in tissues obtained from BN (RT1n) to BN rats (group 1), and DA (RT1a) to BN rats (group 2). The ET-1 levels in group 1, determined by radioimmunoassay, remained low in the serum, liver, and bile, but in group 2, they peaked on postoperative day (POD) 5 in the liver, kidney, bile, and urine, at 344 +/- 31.6 pg/gwet, 306 +/- 97.4 pg/gwet, 1008 +/- 258 pg/day, and 156 +/- 45 pg/day, respectively, whereas levels in the serum peaked on POD 7 at 38.7 +/- 13.1 pg/ml. In the portal vein (PV) ET-1 showed extremely high levels without statistical difference between groups 1 and 2, at 93.0 +/- 15.5, and 83.0 +/- 9.84 pg/ml on POD 7, respectively. However, in the suprahepatic vena cava (SHVC) and the abdominal aorta (AO), the ET-1 levels were statistically higher in group 2 compared to group 1 (P < 0.01). Immunohistochemical staining showed decreased staining of the liver and kidney in group 2 on POD 7. In conclusion, increasing levels of ET-1 were released from the liver and kidney during the early stage of rejection, resulting in the high ET-1 levels in these tissues, which were cleared promptly. However, an increased production of ET-1 was not observed in association with the release of ET-1.

Adult T-cell leukemia/lymphoma with a giant gastric tumor: a case report

A rare case of adult T-cell leukemia/lymphoma with a giant exophytic gastric tumor invading the anterior abdominal wall is presented. The patient was a 52-year-old woman, who had a history of strongyloidiasis. Although the patient was serologically positive for HTLV-I antibody, there were no lymphoma cells in the peripheral blood or systemic lymphadenopathy. After two cycles of combination chemotherapy, the tumor was surgically resected. The pathological diagnosis of the resected specimen was T-cell lymphoma of the diffuse mixed cell type. Flow-cytometric analysis of the lymphoma showed a CD4+ and CD8+ phenotype. One month after surgery, the patient developed hypercalcemia, resulting in acute renal and respiratory failure, and died. The prognosis of lymphoma-type ATL is known to be extremely poor, and thus we should bear in mind that ATL can take the form of a primary gastric mass without leukemic manifestations.

Changes in tumor necrosis factor-a and interleukin-1 beta production following liver surgery on cirrhotic patients

BACKGROUND/AIMS

The purpose of this study is to investigate the possible participation of inflammatory cytokine release from macrophages/monocytes following liver surgery on cirrhotic patients in the pathogenesis of postoperative organ failures.

MATERIALS AND METHODS

Postoperative changes in tumor necrosis factor-a and interleukin-1 beta production in peripheral blood monocytes stimulated by lipopolysaccharide were examined in cirrhotic patients with hepatocellular carcinoma undergoing hepatic resections.

RESULTS

Monocytes separated from the blood in cirrhotic patients prior to operation showed a greater ability to produce tumor necrosis factor-a and interleukin-1 beta than those in healthy volunteers. Monocytes in postoperative cirrhotic patients showed a greater ability to produce tumor necrosis factor-a and interleukin-1 beta in the presence of lipopolysaccharide than healthy controls and preoperative cirrhotic patients. In the case of postoperative hepatic failure, tumor necrosis factor-a and interleukin-1 beta production in monocytes showed a remarkable rise along with progression toward hepatic failure.

CONCLUSION

These results indicate that tumor necrosis factor-a and interleukin-1 beta play an important role in the pathogenesis of postoperative liver failures. When there are any stimuli to produce cytokines in monocytes, such as ischemia, significant tissue injury and/or endotoxin, organ failures could develop and progress subsequently.

Mercuric ion uptake by Escherichia coli cells producing Thiobacillus ferrooxidans merC

The merC gene of Thiobacillus ferrooxidans was overexpressed in Escherichia coli under the control of the tac promoter. MerC protein synthesized in E. coli has a N-terminal amino acid sequence of S-A-I-X-R-I-I-D-K-I-G-I-V-G-, which agrees with the amino acid sequence deduced from its nucleotide sequence except that an initiating methionine residue was removed. The MerC protein was localized in the particulate (membrane) cell fraction, and not in the soluble cytoplasmic fraction. E. coli cells carrying a plasmid containing the tac promoter-directed merC showed 203Hg2+ uptake in an isopropyl-1-thio-beta-D-galactopyranoside (IPTG)-dependent manner.

Adenovirus-mediated gene transfer using ex vivo perfusion of the heart graft

A replication-deficient adenovirus was used for ex vivo gene transfer into rat heart grafts under conditions simulating clinical transplantation. The adenoviral vector, AdHCMVsp1LacZ, containing an expression cassette of Escherichiae coli lacZ, was used to perfuse heart grafts during cold ischemia before transplantation. Heart grafts were perfused with University of Wisconsin (UW) solution containing either 0 pfu, 5 x 10(10) pfu, or 1 x 10(11) pfu of viral vector, and were preserved for either 2 or 4 h and then transplanted into syngeneic recipients. The animals were killed at 1, 7, and 14 days after transplantation. The infection rate was assessed by histochemical staining for beta-galactosidase. Using polymerase chain reaction (PCR), viral DNA presence was confirmed in every graft perfused with viral vectors. The protein production from the transfected gene was confirmed by a functional protein assay. An efficient gene transfer was achieved with an infection rate of 1%-1.5% for all cardiac myocytes, as assessed by 5-bromo-4-chloro-indolyl-beta-D-galactopyranoside (X-gal) staining. All studies were negative in the control grafts. Gene expression persisted for at least 10 days after transplantation. We thus conclude that an efficient adenovirus-mediated gene transfection and expression of gene products can be achieved in ex vivo perfusion of the heart graft during cold preservation.

[Correlation between intratumor DNA ploidy distribution pattern and clinicopathologic variables in large-bowel carcinoma]

Surgically resected specimens of 139 cases of large-bowel carcinoma were analysed in this study. Each carcinoma was cut out in stepwise section through the whole tumor, and flow cytometric DNA measurement was performed for each section. The intratumor DNA ploidy distribution pattern decided in this way was classified into 5 types (Type A-E). The 139 cases of carcinoma comprised 19 cases of Type A, 27 Type B, 11 Type C, 37 Type D and 45 Type E. The intratumor DNA ploidy distribution pattern showed a statistically significant correlation to tumor size, gross type, depth of invasion, growth pattern at the tumor margin, venous permeation of visceral wall, DNA Index and Dukes stage. Among these 5 types of carcinoma, carcinoma showing Type E was seen most frequently, even in the earlier stage, and found most frequently among the cases showing invasive growth pattern at the tumor margin, positive venous permeation in the visceral wall and DNA Index of more than 1.7. Therefore, the intratumor DNA ploidy distribution pattern seemed to reflect the degree of tumor malignancy as well as that of tumor advancement. Moreover, Type E pattern of carcinoma appeared to reveal the highest grade of malignancy, and early detection of this type seemed to be necessary in order to improve survival after surgery.

[Correlation between intratumor DNA ploidy distribution pattern and prognosis by tumor stage in colorectal carcinomas]

Curatively resected specimens of 124 cases of colorectal carcinoma, and 6 cases of colorectal carcinoma showing hematogenous metastasis were used in this study. Each carcinoma was cut out in stepwise section through the entire tumor. DNA ploidy for each section was determined by flow cytometry, and the intratumor DNA ploidy distribution pattern was decided, and divided into 5 types (Type A-E). These 5 types were broadly divided into 2 types; predominantly diploidy type (Type A, C) and predominantly aneuploidy type (Type B, D, E). A statistically significant difference was seen in the 5-year survival between 25 cases of the predominantly diploidy type (100%) and 99 cases of the predominantly aneuploidy type (76.7%). However, there was no statistically significant difference in survival between these 2 types in any Dukes stage. The intratumor DNA ploidy distribution pattern in 6 cases of colorectal carcinoma showing hematogenous metastasis comprised 3 cases of Type E, 2 Type D and 1 Type B. And that of 8 cases of curatively resected colorectal carcinoma showing hematogenous metastasis postoperatively comprised 5 cases of Type D, 2 Type E and 1 Type B. Thus, a close correlation between the aneuploidy predominant type, especially Type D as well as Type E, and hematogenous metastasis, was suggested.

Novel NTP binding property of rice dwarf phytoreovirus minor core protein P5

Rice dwarf phytoreovirus (RDV) mRNA synthesized from purified virion has a cap structure, m7GpppAm-, which suggests the presence of guanylyltransferase activity in the virion. We attempted to identify the enzyme involved in the cap formation by using a nucleoside triphosphate binding assay. Incubation of virion with [alpha-32P]GTP resulted in labeling of an 89-kDa protein that had not previously been identified in purified virus preparations. Interestingly this protein also covalently bound UTP and ATP, which is not a property of the known guanylytransferases. RDV particles catalyzed GTP-PPi, dGTP-PPi, ATP-PPi, and UTP-PPi exchange reactions. In SDS-polyacrylamide gel electrophoresis, the 89-kDa protein comigrated with the S5-coded protein, P5, which had been expressed by a baculovirus vector. Moreover, the labeled 89-kDa protein was precipitated by an antiserum against this recombinant RDV P5. Careful reinvestigation of purified virus particles by SDS-polyacrylamide gel electrophoresis and Western blotting analyses showed that they contained a small amount of P5 (<0.5% of the total protein) within the core. These results may suggest that the minor core protein of RDV, which is coded by S5, is a candidate guanylyltransferase, although the biological significance of its ATP and UTP binding activities remains largely unknown.

Cloning and sequence analysis of czc genes in Alcaligenes sp. strain CT14

We have isolated 14 cadmium (Cd)-resistant, soil-borne bacteria. Among those, strain CT14, which was identified as an Alcaligenes sp., has a czc (cadmium, zinc, and cobalt divalent cation resistant determinant) system. Here we report the nucleotide sequence of 4 genes (czcCBAD) of the system. CzcCBA showed over 98% identity with those of A. eutrophus CH34, however, CzcD, the distal gene product, was 117 amino acids longer than that (199 amino acids) of A. eutrophus CH34, and had considerable similarity to the members of the CDF (cation diffusion facilitator) family proteins all over the region.

[Iatrogenic injury of tracheobronchial membranous wall]

Tracheobronchial injuries remain uncommon, but they are of great significance, because they can result in death or substantinal functional compromise. Such injuries are mostly from blunt trauma and motor vehicle accidents, but there also is an incidence of penetrating thoracic trauma inclunding iatrogenic accidents. Three cases of iatrogenic injury of tracheobronchial membranous wall were reported. Two cases were tear at the membraneous portion of the left main bronchus and trachea by forceful endotracheal intubation. Another case was tracheal membranous wall injury during operation at blunt dissection for esophageal carcinoma. We reported the emergent managements for iatrogenic injury of tracheobroncheal membranous wall in differents 3 ways. We should select the best treatment according to the condition of the patients and situation of the injury.

Nucleotide and amino acid sequences for cytochrome caa3-type oxidase of Bacillus stearothermophilus K1041 and non-Michaelis-type kinetics with cytochrome c

A pseudo-sigmoidal cytochrome c-dependence curve of oxidase activity was observed with cytochrome oxidase from the Bacillus stearothermophilus strain K1041, while the other thermophilic Bacillus PS3 which has been extensively studied possessed normal Michaelis-Menten type kinetics. The genes coding for four subunits of cytochrome caa3-type oxidase and for heme O synthase were isolated from a genomic DNA library of K1041 by using a PS3 DNA fragment containing the highly-conserved region of the largest subunit as a probe, and sequenced. Most residues in subunits I (COI/caaB product), III (COIII/caaC product), and IV (COIV/caaD product) of K1041 were highly conserved when compared with those of PS3. However, the sequence of K1041 subunit II (COII/caaA product) was distinctly different from that of the PS3 subunit II. These Bacillus COIIs have an additional sequence for cytochrome c after the CuA binding protein portion with two transmembrane segments which is homologous to the mitochondrial counterpart, and represents the site of electron ingress. Several charged residues in the vicinity of cytochrome c moiety are replaced by oppositely charged residues. It is likely that these amino acid replacements in subunit II are the cause of the abnormal sigmoidal saturation curve for extrinsic cytochromes c of the K1041 enzyme.

Plexiform leiomyoma of the esophagus: a peculiar gross variant simulating plexiform neurofibroma

A plexiform variant of leiomyoma of the esophagus in a 51-year-old woman is reported. The patient was diagnosed with a tumor of the esophagus in an X-ray mass survey of the upper gastrointestinal tract. She was referred to the Ryukyu University Hospital for further examination. She appeared healthy with no complaints. Upper gastrointestinal series revealed an oval, well-defined filling defect in the lower esophagus just above the esophagogastric junction. Endoscopy revealed an undulating bulge covered with normal esophageal mucosa. Endoscopic ultrasonography showed a sharply demarcated hypoechoic mural tumor with internal linear pattern, with no evidence of penetration into the surrounding tissue. These findings were evaluated as consistent with a leiomyoma. Removing the tumor by enucleation was easily accomplished. Unexpectedly, on gross inspection, the tumor was a plexiform type, mimicking a plexiform neurofibroma. Light and electron microscopic examination and immunohistochemistry of the tumor tissue confirmed leiomyoma. Since the enucleation of the tumor, the patient has been free of recurrence and symptoms for 1.5 years at the time of this report.