Effect of the initial bolus volume of recombinant tissue-type plasminogen activator on coronary recanalization and infarct size in Japanese acute myocardial infarction patients. Kumamoto University Myocardial Infarction Study (KUMIS) Group

Coronary recanalization rate and infarct size were compared between 2 different methods of intravenously administering recombinant tissue-type plasminogen activator (rt-PA) 41.4 mg; 1) an initial bolus dose of 30% followed by infusion of the remainder over 60 min (30% group), and an initial bolus dose of 10% followed by infusion of the remainder over 60 min (10% group). Thirty min after beginning rt-PA infusion, the coronary recanalization rate was higher in the 30% group than in the 10% group (82.9% (34/41) vs 53.7% (22/41), p < 0.01). The peak creatine kinase and peak creatine kinase-MB levels were lower in the 30% group than in the 10% group. We conclude that a higher initial bolus dose of rt-PA gives a higher rate of recanalization of the infarct-related artery at the very early phase, and probably leads to a smaller infarct size.

Automated smear counting and data processing using a notebook computer in a biomedical research facility

An automated smear counting and data processing system for a life science laboratory was developed to facilitate routine surveys and eliminate human errors by using a notebook computer. This system was composed of a personal computer, a liquid scintillation counter and a well-type NaI(Tl) scintillation counter. The radioactivity of smear samples was automatically measured by these counters. The personal computer received raw signals from the counters through an interface of RS-232C. The software for the computer evaluated the surface density of each radioisotope and printed out that value along with other items as a report. The software was programmed in Pascal language. This system was successfully applied to routine surveys for contamination in our facility.

[The relationship between the improvement of cardiac function and the myocardial uptake of I-123 metaiodobenzylguanidine in patients with dilated cardiomyopathy treated by beta-blocker]

Chronic beta-blocker therapy improves hemodynamics and cardiac function in patients with idiopathic dilated cardiomyopathy. However, the change in myocardial uptake of I-123 metaiodobenzylguanidine (123I-MIBG) before and after treatment has not been determined. Myocardial imaging with 123I-MIBG was performed before and 2 or 3 months after beta-blocker (bisoprolol) therapy in 11 patients with dilated cardiomyopathy. The following parameters were compared before and after the treatment: 1) New York Heart Association functional class, 2) X-ray cardiothoracic ratio, 3) heart rate and blood pressure, 4) echocardiographic data (left ventricular end-diastolic and end-systolic diameters, and left ventricular ejection fraction), 5) plasma concentrations of epinephrine, norepinephrine and human atrial natriuretic peptide (HANP), and 6) exercise tolerance time by treadmill. The heart-to-mediastinum ratio of 123I-MIBG activities obtained 3 hours after intravenous injection (late H/M) and washout rate improved significantly after beta-blocker therapy. Cardiothoracic ratio, heart rate, echocardiographic parameters, HANP and exercise tolerance also improved significantly. Late H/M had no significant relationship with any of the clinical parameters, but washout rate was significantly related to left ventricular ejection fraction. These findings suggest that washout rate may be useful to assess the effect of short-term beta-blocker therapy in dilated cardiomyopathy patients.

Steps involved in activation of the pro-matrix metalloproteinase 9 (progelatinase B)-tissue inhibitor of metalloproteinases-1 complex by 4-aminophenylmercuric acetate and proteinases

The precursor of matrix metalloproteinase 9 (pro-MMP-9, progelatinase B) noncovalently binds to tissue inhibitor of metalloproteinases (TIMP)-1 through the C-terminal domain of each molecule. We have isolated the proMMP-9.TIMP-1 complex from the medium of human fibrosarcoma HT-1080 cells and investigated the activation processes of the complex by 4-aminophenylmercuric acetate, trypsin, and matrix metalloproteinase 3 (MMP-3, stromelysin 1). The treatment of the proMMP-9.TIMP-1 complex with 4-aminophenylmercuric acetate or trypsin converts proMMP-9 to lower molecular weight species corresponding to active forms, but no gelatinolytic activity is detected. The lack of enzymic activity results from binding of TIMP-1 to the activated MMP-9. The treatment of the proMMP-9.TIMP-1 complex with a possible physiological proMMP-9 activator, MMP-3, does not reveal any gelatinolytic activity unless the molar ratio of MMP-3 to the complex exceeds 1. This is due to the inhibition of MMP-3 by TIMP-1 forming a ternary proMMP-9.TIMP-1.MMP-3 complex. The formation of the ternary complex weakens the interaction between proMMP-9 and TIMP-1, resulting in partial dissociation of the complex into proMMP-9 and the TIMP-1.MMP-3 complex. When MMP-3 is in excess, the propeptide is completely processed, and the full activity of MMP-9 is detected. Similarly, the proMMP-9.TIMP-1 complex inhibits MMP-1 (interstitial collagenase) and in turn renders the proMMP-9 activable by a catalytic amount of MMP-3. These results suggest that formation of the proMMP-9.TIMP-1 complex regulates extracellular matrix breakdown in tissue by switching the predominant MMP activity from one type to another.

Effects of bradykinin on Ca2+ mobilization and prostaglandin E2 release in human periodontal ligament cells

In fura-2-loaded human periodontal ligament (HPDL) cells, bradykinin induced a rapidly transient increase and subsequently sustained increase in cytosolic Ca2+ ([Ca2+]i). When external Ca2+ was chelated by EGTA, the transient peak of [Ca2+]i was reduced and the sustained level was abolished, implying the Ca2+ mobilization consists of intracellular Ca2+ release and Ca2+ influx. Thapsigargin, a specific Ca(2+)-ATPase inhibitor for inositol 1,4,5-trisphosphate (1,4,5-IP3)-sensitive Ca2+ pool, induced an increased in [Ca2+]i in the absence of external Ca2+. After depletion of the intracellular Ca2+ pool by thapsigargin, the increase in [Ca2+]i induced by bradykinin was obviously reduced. Bradykinin also stimulated formation of inositol polyphosphates including 1,4,5-IP3. These results suggest that bradykinin stimulates intracellular Ca2+ release from the 1,4,5-IP3-sensitive Ca2+ pool. Bradykinin stimulated prostaglandin E2 (PGE2) release in the presence of external Ca2+, but not in the absence of external Ca2+. Ca2+ ionophore A23187 and thapsigargin evoked the release of PGE2 in the presence of external Ca2+ despite no activation of bradykinin receptors. These results indicate that bradykinin induces Ca2+ mobilization via activation of phospholipase C and PGE2 release caused by the Ca2+ influx in HPDL cells.

Aggressive surgery for pancreatic duct cell cancer: feasibility, validity, limitations

Pancreatic duct cell cancer is characterized by a low resectability rate and a low long-term survival rate. Between September 1974 and December 1992 in our institution, 149 (59%) of the 253 patients with this cancer underwent resection. The operative procedures were pancreatoduodenectomy in 105 patients, total pancreatectomy in 36, and distal pancreatectomy in 8. The tumor was extirpated with extensive dissection of the lymph nodes and excision of the nerve plexus in the retroperitoneum. Of the 149 patients, 79 (53%) underwent combined resection of the pancreas and the portal vein; 16 of the 79 patients also underwent resection of the adjacent arteries. Three patients died within 30 days after surgery, and 17 other patients succumbed within 2 to 7 months. The mortality among patients undergoing pancreatectomy and resection of the portal vein (9.5%) was similar to that of patients with pancreatectomy alone (10%). Curative resection was necessary for long-term survival. The 5-year survival rate in 61 patients with the curative resection was 15%. Ten patients lived more than 5 years. Even patients with lymph node metastases and cancer invasion of the portal vein had a prolonged survival. Intraoperative irradiation was carried out in 35 patients to improve the survival rate, but without success. Infusion chemotherapy with 5-fluorouracil via the portal vein was tried in 25 patients, resulting in a decrease in liver metastasis. We have made some progress in the first step toward improving treatment, although we are far from the goal and it is necessary to conduct additional trials.

[Significance of MMP-9 and TIMP-1 production during liver metastasis in colorectal cancer]

We have investigated the expression of matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinases 1 (TIMP-1) in colorectal cancer by the immunostaining (avidin-biotin peroxidase complex method) and in situ hybridization (ISH). Both MMP-9 enzyme and messenger RNA (mRNA) for MMP-9 were located in tumor cells, neutrophils, monocyte-macrophages and fibroblasts in colorectal cancer tissue. The location of TIMP-1 mRNA was similar to that of MMP-9 mRNA in colorectal cancer tissue. There was a strong correlation between the expression of MMP-9 in tumor cells and liver metastasis. The expression of mRNA for TIMP-1 in stromal cells in cases associated with liver metastasis was significantly higher than that in cases without liver metastasis. However, in tumor cells, predominant expression of MMP-9 mRNA was observed in all cases associated with liver metastasis. These results suggest that MMP-9 might play an important role in hematogenous metastasis in colorectal cancer and that the balance between the production of MMP-9 and TIMP-1, in particular in tumor cells, is important as one of the pathogenesis of tumor metastasis.

Immunocytochemical comparison of posttranslationally modified forms of tubulin in the vestibular end-organs of the gerbil: tyrosinated, acetylated and polyglutamylated tubulin

Specific antibodies against alpha-tubulin, acetylated alpha-tubulin, tyrosinated alpha-tubulin and polyglutamylated alpha- and beta-tubulin were used to compare the distribution of posttranslationally modified tubulin in the vestibular end-organs of the gerbil. Antibodies to acetylated tubulin labeled a dense network of microtubules in the hair cells and bundles of microtubule in the supporting cells. Nerve fibers within and below the epithelium were weakly labeled. This localization paralleled that seen with antibodies to alpha-tubulin which labeled all microtubules present in the cells. Antibodies to tyrosinated tubulin labeled networks and bundles of microtubules in both hair cells and supporting cells and in addition gave intense, diffuse labeling in the cytoplasm of both cell types. It also labeled the nerve fibers. Antibodies to polyglutamylated tubulin were localized mainly in nerve fibers, and in the calyces the labeled microtubules were found running circumferentially around the type I sensory hair cells. Thus, tyrosinated tubulin was found in the fine networks of microtubules in both the sensory and supporting cells. Acetylated tubulin was found in the dense networks and bundles of microtubules in the sensory and supporting cells, but did not colocalize with polyglutamylated tubulin, which was found predominantly in the nerve fibers. The labeling patterns for the tyrosinated tubulin and posttranslationally modified tubulins in the sensory and supporting cells of the vestibular end organs differ from that seen in the organ of Corti and may reflect differences in the stability of the microtubules and the mechanical properties of the sensory epithelium.

[A case of successful treatment of chronic sternal osteomyelitis and mediastinitis after ascending aorta and hemiarch reconstruction]

Mediastinitis is one of severe and fatal complications after cardiac surgery, especially in the presence of a prosthetic graft. A 70-year-old male, who was suffered from chronic sternal osteomyelitis and mediastinitis after ascending aorta and hemiarch reconstruction was reported. He developed high fever and leucocytosis on the 16th postoperative day. Wound culture was positive for Grampositive organisms. He was diagnosed as having sternal osteomyelitis and mediastinitis and treated by sternal bone debridement and irrigation with dilute povidone iodine solution with no effects. Total excision of the infected sternum, irrigation with non-diluted solution of povidone iodine and omental transfer were performed successfully. The literature regarding omental transfer for mediastinitis and infected prosthetic grafts was briefly reviewed.

Glucocorticoid regulation of bone sialoprotein (BSP) gene expression. Identification of a glucocorticoid response element in the bone sialoprotein gene promoter

Glucocorticoids modulate the development and growth of many organs through interactions with a specific intracellular receptor (glucocorticoid receptor) that regulates gene transcription through a cognate element, the glucocorticoid response element (GRE), in the promoter of target genes. In bone formation glucocorticoids stimulate osteoblast differentiation and the formation of bone matrix. Recent studies have demonstrated that the induction of the bone sialoprotein (BSP) gene is associated with osteoblast differentiation and de novo bone formation. To determine the molecular pathways of glucocorticoid regulation of BSP expression, we have analyzed the effects of the synthetic glucocorticoid, dexamethasone, on the expression of the BSP by bone cells in vitro. At 10 nM, dexamethasone induced BSP expression in association with bone tissue formation by confluent fetal rat calvarial cells and adult rat marrow cells and also stimulated BSP expression up to sixfold in osteoblastic cells (UMR 106-6 and ROS 17/2.8 cells). Most of the stimulation was blocked by cycloheximide, indicating direct and indirect mechanisms of BSP gene regulation. Nuclear 'run-on' transcription analysis revealed an up to twofold increase in transcription corresponding to the increase in mRNA that was unaffected by cycloheximide. Analysis of BSP mRNA in the presence of a transcription inhibitor (5,6-dichloro-1-beta-D-ribofuanosyl benzimidazole) by Northern hybridization revealed that the stability of the BSP mRNA was not significantly altered by dexamethasone, indicating that the major, indirect, stimulation of BSP expression involves a nuclear post-transcriptional mechanism. To study the direct effects of dexamethasone, nucleotide sequence analysis of the rat BSP promoter was extended upstream to position -2992 and downstream to +2282 in the first intron. Transient transfection analyses, using various rat BSP promoter constructs linked to a luciferase reporter gene, and gel mobility shift assays were used to identify a putative glucocorticoid response unit comprising three GRE half-sites and a putative AP-1 site, located within positions -906 to -931 upstream from the translation start site of the BSP gene promoter. BSP transcription was stimulated approximately 1.5-fold by dexamethasone through this GRE, indicating that its direct effects are mediated by glucocorticoid receptor binding to this site. These studies, therefore, have identified both indirect and direct pathways of glucocorticoid regulation of BSP gene expression, the direct effects being mediated by a GRE in the rat BSP promoter through which the effects of glucocorticoids on BSP gene transcription appear to be regulated.

Clinical evaluation of gastric fundic gland polyps without familial polyposis coli

BACKGROUND

Assessments were made of 63 cases of fundic gland polyposis (FGP) unassociated with adenomatosis coli. These cases were evaluated by radiological examination over 2 years follow-up. All polyps were pathologically confirmed by endoscopic biopsies.

METHODS

Most cases were asymptomatic when diagnosed during mass radiological surveys of the upper gastrointestinal tract. The majority of patients ranged in age from 40-60 years, and the polyps numbered fewer than 20 in 55 cases (87.3%). Polyps were detected in the fundic glands using the congo red test and by biopsies.

RESULTS

All serum gastrin values were within the normal range. During the course of this study, the polyps of 13 cases (20.6%) increased and those of three cases (4.8%) decreased or resolved completely.

CONCLUSION

From these findings it is considered that FGP are observed in stomachs with less atrophy, and that polyps follow courses in which they increase, decrease, disappear, along with atrophy.

Immunological differentiation of human tissue-nonspecific type alkaline phosphatases by a monoclonal antibody to the enzyme of human osteoblast-like cells

Monoclonal antibodies against alkaline phosphatase [ALP; ortho-phosphoric monoester phosphohydrolase, alkaline optimum, EC 3.1.3.1.] of cultured human osteoblast-like cells (HBC) were raised in mice. Immuno-reactions of tissue-nonspecific type ALP from human bone, dental pulp, liver and kidney as well as intestinal and placental types to the monoclonal antibodies were compared by a dot immunoassay and ELISA. One clone was able to recognize antigenic differences among tissue-nonspecific type ALPs in addition to intestinal and placental ALPs; it reacted favorably with ALPs from HBC, human bone, kidney and dental pulp, but not with human liver enzyme. Similarly, the antibody immunoreacted with bone-derived ALP but not with liver-derived enzyme present in human serum. The present monoclonal antibody preparation can be utilized in basic studies as well as in clinical laboratory tests to distinguish minor heterogeneity among human ALPs.

Effect and safety of liposome-encapsulated hemoglobin neo red cells (NRCs) as a perfusate for total cardiopulmonary bypass

We developed a liposome encapsulated hemoglobin named Neo Red Cells (NRC), NRC (1) readily circulates, (2) shows a high oxygen transport efficiency, and (3) has a strong capsule membrane. In this study, we evaluated the effect of NRC as a priming solution for total cardiopulmonary bypass (TCPB) using a dog. The TCPB was started after removal of 57.1-73.3% of autologous blood and continued for 7 hours. During TCPB using NRC, the vascular resistance (VR) decreased to 1/4 of VR when red blood cells (RBC) were used. This change suggests that NRC, the viscosity of which is lower than that of RBC, reduced the load on the circulation system. The oxygen volume delivered by NRC was higher than that delivered by RBC, resulting in a greater oxygen consumption with NRC. During TCPB using NRC, the serum LDH level was lower than that using RBC. So we concluded that NRC compensated for the reduction in the oxygen transport ability, which is a disadvantage of dilution TCPB, and further increased the circulation improving effect and anti-hemolytic effect, which are advantages of the procedure. It, thus, enhanced both the safety and effectiveness of dilution TCPB.

Total pelvic exenteration for locally advanced colorectal carcinoma--postoperative complications

This study was designed to clarify the postoperative major complications of total pelvic exenteration for locally advanced colorectal cancer. Twenty-six patients (primary disease: 17, recurrent disease: 9) were retrospectively studied. Major complications developed in 30.8% (8 of 26); in 23.5% (4 of 17) for a primary disease and in 44.4% (4 of 9) for a recurrent disease. Only 2 patients (7.7%) died within 30 days after the operation; one patient died of hepatic failure and another of pelvic sepsis. Postoperative ileus developed at a high rate of 11.5% (3 of 26). Ileo-ileal anastomotic leakage developed at a rate of 7.7% (2 of 26) and it commonly occurred following irradiation. The remaining one patient had gastrointestinal bleeding. These 6 patients surviving the operation were successfully managed conservatively. Conclusion was as follows: Total pelvic exenteration should be performed carefully and aggressively regardless of the development of postoperative complications.

Regulation of bone sialoprotein gene transcription by steroid hormones

During the initial formation of bone, dentine and cementum in tooth morphogenesis, fully differentiated osteoblasts, odontoblasts and cementoblasts express bone sialoprotein (BSP), a mineralized tissue-specific acidic glycoprotein that has been implicated in the nucleation of hydroxyapatite crystal growth. The expression of BSP is regulated by steroid hormones that modulate mineralized tissue formation. Thus, the transcription of the BSP gene is induced by glucocorticoids in association with osteoblast differentiation and glucocorticoids also stimulate the expression of BSP in differentiated osteoblasts. In contrast, however, vitamin D3 suppresses bone formation and abrogates the expression of BSP. Our studies, using the osteoblastic cell lines ROS 17/2.8 and UMR 106-06, have revealed that the glucocorticoid (10(-8) M dexamethasone; dex) effect on BSP mRNA involves both direct and indirect pathways. To determine the molecular basis of the direct pathway on transcriptional regulation of the BSP we have isolated and characterized the promoter regions of both the human and rat BSP genes. The promoters are characterized by a highly conserved region (BSP box) encompassing the immediate promoter region, which includes a unique inverted TATA box overlapped by a putative (DR3) vitamin D3 response element (VDRE). Possible glucocorticoid response elements are present approximately 1 kb and approximately 1.4 kb further upstream. Transient transfection analysis of chimeric constructs linked to a luciferase reporter gene have shown Dex-stimulated expression in constructs that include one or both GREs, whereas vit D3 suppresses expression in a short construct that includes the VDRE.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of bone-type alkaline phosphatase mRNA from human periodontal ligament cells

Tissue-nonspecific-type alkaline phosphatase is found in the bone, liver, kidney, and other tissues, and its gene consists of 12 exons with the coding sequence beginning in the second exon. Recently, an alternative noncoding first exon was identified in the liver message which differed from that of the previously known osteoblast-derived cDNA sequence. Although these two mRNAs produce an identical protein, they have different promoter regions. The periodontal ligament tissue expresses a high level of alkaline phosphatase activity. To identify its mRNA type, we isolated a full-length cDNA for alkaline phosphatase from a cultured human periodontal ligament cell expression library, using bone-derived tissue-nonspecific alkaline phosphatase cDNA as a hybridization probe. The size of this clone was 2.5 kb, and its 5' and 3' untranslated sequences were identical to those of the human tissue-nonspecific type isolated from osteoblastic cells but not to those of the liver type. In addition, the same fragments as in bone-derived tissue-nonspecific-type cDNA were detected by the treatment of the cDNA clone with restriction enzymes Hinc II and Pst I. The results suggest that expression of the same alkaline phosphatase isozyme in human periodontal ligament cells may be regulated by the same transcriptional mechanism as in bone.

Crossed ureteral ectopia with an ectopic blind-ending ureter

A rare case of multiple urological anomalies is presented. The chief complaint of the patient, a 12-year-old girl, was urinary incontinence. Radiologic and endoscopic examinations revealed that the patient had a normal left kidney and ureter, a left ectopic blind-ending ureter that opened near the neck of the bladder, and right complete double ureters with an ectopic orifice that opened on the left of the external urethral meatus. This orifice was responsible for her urinary incontinence. Right ureteroneocystostomy was performed and the incontinence was cured. An attempt was made to explain the embryological origin of the anomalies observed in this case. We postulated that during development, on the left, there were three ureteral buds on the mesonephric duct. The first bud was at the normal position and drained the left kidney in a normal manner. The second bud was cranial from the normal position on the mesonephric duct and was associated with growth in an abnormal direction. This bud made contact with the upper portion of the right metanephric mass. The last bud grew between the two aforementioned buds. This bud was not draped by the metanephric mass and became the blind-ending ureter. On the right, one ureteral bud was located on the mesonephric duct and it made contact with a metanephric mass that became the right kidney. The upper part of the right kidney was drained by the ureter that had originally been located on the left mesonephric duct. This condition should be termed crossed ureteral ectopia rather than crossed renal ectopia, since the ureter was the structure that crossed.

Clinicopathologic characteristics of large bowel cancer developing after radiotherapy for uterine cervical cancer

PURPOSE

This study was designed to clarify the characteristics of large bowel cancer developing after radiotherapy for uterine cervical cancer.

METHODS

A retrospective chart review was performed.

RESULTS

The latent period was a mean of 20.5 years. The most common site was in the rectum (16/32). Mucin-producing carcinoma was observed in 53.1 percent, with an especially high rate of 75 percent in the rectum. Histologic radiation damage was also demonstrated at a high rate of 64.3 percent.

CONCLUSIONS

It was difficult to judge from clinicopathologic findings whether large bowel cancer developed with relation to radiation effect. We emphasize, however, that the characteristics are different from ordinary large bowel cancer. Particular consideration should be given to the high incidence of mucin-producing carcinoma.

Cellular localization of matrix metalloproteinases in the abdominal aortic aneurysm wall

PURPOSE

This study explores the source(s) of the matrix-degrading proteinases, matrix metalloproteinase 1 (MMP-1; interstitial collagenase), matrix metalloproteinase 3 (MMP-3; stromelysin 1), and matrix metalloproteinase 9 (MMP-9; gelatinase B), previously implicated in abdominal aortic aneurysm (AAA) development. The possible involvement of the plasmin cascade in the activation of these proteinases was also explored by examining the presence of the urokinase-type plasminogen activator (uPA) in aneurysm wall.

METHODS

Immunohistochemical techniques were used to detect the presence of MMP-1, MMP-3 and MMP-9 proteins and uPA in fixed, paraffin-embedded tissue sections from AAA (n = 10) and control (n = 2) aortas.

RESULTS

The MMP-9 protein was localized to mononuclear cells in the AAA wall. Dual-labeling techniques confirmed the identity of these cells as macrophages. The MMP-3 protein and uPA were also detected primarily in the macrophage-like mononuclear cells infiltrating the aneurysmal aorta. Immunoreactive material to MMP-1 was demonstrated in mesenchymal cells of the AAA wall suggesting alternative expression and delivery of this enzyme in AAA.

CONCLUSIONS

This work establishes the role of macrophages in the delivery, expression, and possible activation of matrix destructive proteinases during AAA pathogenesis and suggests a role for the activation of MMPs in the progression of the disease.

A case of radiation-induced rectal cancer developing after a long-term follow-up

A case of radiation-induced rectal cancer is presented. In November, 1971, a 58-year-old woman had a stage II squamous cell carcinoma in the uterine cervix. She underwent a hysterectomy and postoperative radiotherapy. External pelvic irradiation of 10 MV x-ray was carried out in 15 fractions of 2 Gy daily, with a total dose of 30 Gy, and intracavitary radium insertion with a total dose of 960 mg hours (20 mg x 48 hours). She had been followed-up in our department since 1972, when rectal bleeding occurred. Proctoscopy and periodical biopsies were performed when the patient visited our hospital. There was no evidence of malignant tumor cells nor of recurrent cervical cancer from 1973 to 1989. In August, 1990, a biopsy specimen taken from a rectal ulcer revealed a malignant mucinous adenocarcinoma. The time interval between the radiotherapy and the development of the rectal cancer was 19 years. Microscopically, the main lesion was situated in the granulation tissue covered with the regenerating mucosal epithelium, and histologically was found to be a mucinous adenocarcinoma. Other radiation damage was additionally found including colitis, endarteritis and intestinal wall fibrosis. The evidence strongly suggested the present case to be one of radiation-induced rectal cancer.

Primary linitis plastica carcinoma of the colon and rectum

BACKGROUND

Linitis plastica carcinoma (LPC) usually shows a scirrhous growth pattern with a severe stromal desmoplastic reaction. Another growth pattern showing lymphangiosis carcinomatosa rather than scirrhous growth pattern, however, was noted. This study was designed to clarify the clinical and pathologic characteristics of colorectal LPC.

METHODS

Linitis plastica carcinoma was reviewed clinicopathologically and classified into two types according to the histologic growth pattern: The first was a scirrhous type (nine patients) and the second, a lymphangiosis type (three patients).

RESULTS

Grossly, the mucosal surface of the scirrhous type had a granular, cobblestone, gyriform-like appearance. The cancer cells were composed mainly of poorly differentiated or signet-ring cells and were accompanied by a severe stromal desmoplastic reaction; lymphatic permeation was not so marked. Most patients with this type of cancer died of peritonitis carcinomatosa. The mucosal surface of the lymphangiosis carcinomatosa had a smooth and glossy appearance. The cancer cells were composed mainly of moderately differentiated cells, frequently with a glandular formation. Stromal desmoplastic reaction was not so marked. The growth pattern was characterized by lymphangiosis carcinomatosa and marked venous invasion. All patients who had this type died of distant metastases.

CONCLUSION

Perhaps with earlier diagnosis and aggressive treatment, the peritoneal dissemination of scirrhous LPC and distant metastasis of lymphangiosis LPC may be minimized.

Identification of DNA topoisomerases involved in immediate and transient DNA relaxation induced by heat shock in Escherichia coli

The linking number of plasmid DNA in exponentially growing Escherichia coli increases immediately and transiently after heat shock. The purpose of this study was to search for DNA topoisomerases that catalyze this relaxation of DNA. Neither introduction of a topA deletion mutation nor treatment of cells with DNA gyrase inhibitors affected the DNA relaxation induced by heat shock. Thus, DNA topoisomerase I and DNA gyrase are apparently not involved in the process. However, the reaction was inhibited by nalidixic acid or by oxolinic acid in the topA mutant and the reaction was resistant to nalidixic acid in a topA mutant carrying, in addition, the nalA26 mutation. These results are interpreted as indicating that both DNA topoisomerase I and DNA gyrase are involved in the DNA relaxation induced by heat shock.

Combined resection of the pancreas and portal vein for pancreatic cancer

Between March 1976 and December 1992, 137 (57 per cent) of 239 patients with pancreatic duct cell cancer underwent resection; 79 (58 per cent) of the 137 had combined resection of the pancreas and portal vein. Sixty-three of the 79 patients underwent resection of the portal vein alone; six died (mortality rate 10 per cent). The mortality rate was the same as that in 58 patients with no resection of the portal vein. In the remaining 16 patients adjacent arteries were also resected, with seven deaths. Of patients with resection of the portal vein alone who underwent curative resection, four survived more than 5 years, accounting for nearly half of the nine 5-year survivors. Combined resection of the pancreas and portal vein is associated with both an increased resectability rate and improved long-term survival.

Identification of matrix metalloproteinases 3 (stromelysin-1) and 9 (gelatinase B) in abdominal aortic aneurysm

A prominent metalloproteinase activity with an apparent molecular mass of 80 kD and additional activities at 67 through 70, 50, and 32 kD have been observed on casein, gelatin, and elastin gel zymography in extracts from abdominal aortic aneurysms (AAAs). The forms at 80, 50, and 32 kD were isolated by affinity to recombinant tissue inhibitor of metalloproteinases, and the 80-kD and 50-kD components were shown to be derived from matrix metalloproteinase-9 (MMP-9). The relative electrophoretic mobility of these forms under reducing and nonreducing conditions corresponds to those of MMP-9 generated by MMP-3 (stromelysin-1) cleavage, and the active forms of MMP-3 at 45 and 35 kD were detected in aneurysmal extracts under reducing conditions by using specific antibody. Confirmation that the major proteolytic activity observed at 80 kD is MMP-9 was also demonstrated by immunoprecipitation of the activity with specific antibody. Comparative immunoblots of tissue extracts from 10 typical AAA patients, using specific antibody against MMP-9, revealed bands at 92, 82, 67, 51 through 53, 27, 23, and 20 kD under reducing conditions; six aortic control specimens displayed negligible immunoreactivity. This report is the first to show that known activated forms of MMP-3 and MMP-9 are present in the aneurysmal aortic wall and that they may play a role in the destruction of aortic matrix in AAA disease.

Distribution of gelatinase B (MMP-9) and type IV collagen in colorectal carcinoma

Gelatinase B (92 kD, matrix metalloproteinase-9, MMP-9), an enzyme capable of degrading several connective tissue components, was demonstrated by immunolocalization in all specimens of colorectal carcinoma (n = 40), but its distribution between specimens was variable. MMP-9 expression was more frequently observed in advanced tumour stages and was especially prevalent at the side and deep margins of the tumours, and ulceration sites. MMP-9 staining was observed for transformed epithelial cells, macrophages and neutrophils, but seldom for vascular or stromal cells. By contrast, the enzyme was absent from epithelial cells of normal mucosal tissue. Immunostaining of type IV collagen, the major structural component of basement membranes, revealed a general depletion or loss of these structures both within the tumours and at the tumour margins. Dual immunolocalization of MMP-9 and type IV collagen demonstrated that MMP-9 expression at specific sites in the tumour was often inversely related to the distribution of type IV collagen. MMP-9 expression was most pronounced at the invasive tumour margins and in microfoci where tumour cells were in close proximity to inflammatory cells. Such observations support the concept that localized proteolytic and collagenolytic activities contribute to the invasive properties of colorectal tumours.