Effects of exogenously applied calponin on Ca(2+)-regulated force in skinned smooth muscle of the rabbit mesenteric artery

To help elucidate the physiological role of calponin (a thin-filament-linked regulatory protein) in smooth muscle contraction, the effects of its exogenous application were investigated on actin-activated MgAT-Pase activity in crude actomyosin from chicken gizzard, and on contraction induced by Ca(2+)-dependent and -independent means in arterial smooth muscle strips skinned by saponin or beta-escin. Calponin concentration dependently inhibited actin-activated MgATPase activity with a proportional increase in its binding to actomyosin and also attenuated Ca(2+)-induced contractions, in the presence or absence of calmodulin, in skinned arterial strips. Calponin, when phosphorylated by protein kinase C, reduced both its ability to bind to actomyosin and its inhibitory action on actomyosin MgATPase. The phosphorylated calponin also had no effect on the maximum Ca(2+)-induced contraction in skinned smooth muscle, suggesting that these actions of calponin are not nonspecific. Calponin attenuated the Ca(2+)-independent contraction observed in myosin light chain thio-phosphorylated strips, or on application of trypsin-treated myosin light chain kinase. However, calponin had no effect on maintained rigor contraction. These results suggest that in vascular smooth muscle, calponin may play a physiological role in the inhibition of Ca(2+)-regulated force, possibly through a direct action on active actin-myosin interactions.

Mechanisms of vasoconstriction induced by endothelin-1 in smooth muscle of rabbit mesenteric artery

1. The mechanism underlying the vasoconstriction induced by endothelin-1 (ET-1) was investigated by measuring the intracellular concentration of Ca2+ ([Ca2+]i), isometric force and phosphorylation of the myosin light chain (MLC) in endothelium-denuded unskinned and beta-escin-treated skinned smooth muscle from resistance vessels of the rabbit mesentery. The role of protein kinase C (PKC) in the action of ET-1 was studied in skinned smooth muscle using a synthetic peptide, PKC19-36, which corresponds to the autoinhibitory domain of PKC. 2. ET-1 (> 0.1 nM) induced slowly developing, maintained increases in [Ca2+]i and force. Nicardipine completely blocked the ET-1-induced increase in [Ca2+]i. BQ-123 (an inhibitor of the ETA receptor) blocked the ET-1-induced contraction but IRL 1620 (Suc-[Glu9,Ala11,15]-ET-1(8-21), an agonist of the ETB receptor) failed to induce contraction. 3. In ionomycin- and 70 mM K(+)-treated strips, ET-1 shifted the [Ca2+]i-force relationship to the left and enhanced the maximum amplitude of contraction induced by 2.6 mM Ca2+. In skinned smooth muscle treated with ionomycin, Ca2+ (0.1-3 microM) increased both force and MLC phosphorylation, in a concentration-dependent manner. ET-1 with GTP shifted both the Ca(2+)-force and Ca(2+)-MLC phosphorylation relationships to the left without significant changes in the maximum responses. ET-1 with GTP did not change the relationship between force and MLC phosphorylation. Similar effects were observed with phorbol 12,13-dibutyrate (PDBu, an activator of PKC). These results indicate that the sensitivity of MLC phosphorylation to Ca2+ is enhanced both by ET-1 with GTP and by PDBu. 4. PKC19-36 (an inhibitor of PKC) modified neither the contraction nor MLC phosphorylation induced by 0.3 microM Ca2+ but blocked the PDBu-induced enhancement of both these Ca(2+)-induced responses. However, PKC19-36 only partly inhibited the enhancement produced by ET-1 with GTP on the Ca(2+)-induced responses. PKC19-36 did not modify the relationship between force and MLC phosphorylation in the presence either of ET-1 with GTP or of PDBu. By contrast, BQ-123, neomycin and guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) each abolished the ET-1-induced enhancement of the contraction induced by 0.3 microM Ca2+. 5. These results suggest that ET-1 acts on the ETA receptor and increases Ca2+ influxes through an activation of the dihydropyridine-sensitive Ca2+ channel, causing a long-lasting and maintained contraction in resistance vessels of the rabbit mesentery.(ABSTRACT TRUNCATED AT 400 WORDS)

Protection against spinal cord ischaemia: one-shot infusion of hypothermic solution

The protective effect of a one-short infusion of a range of low-temperature hypothermic solutions against spinal cord ischaemia was investigated. Forty rabbits were allocated into five groups each of eight animals. The abdominal aorta of each rabbit was clamped distal to the left renal artery, and also occluded for 30 min above the iliac bifurcation with an inflated 50-gauge French balloon catheter. Ringer's solution with lactate was infused through the catheter port distal to the balloon, at various temperatures (group I, uninfused control; group II, 33 degrees C; group III, 23 degrees C; group IV, 13 degrees C; and group V, 3 degrees C). The neurological status of the hind limbs was assessed on the second postoperative day using the criteria of Tarlov. A further eight rabbits underwent laminectomy at L2 or L3. Temperature probes were inserted into the spinal cord and the cord temperature monitored continuously during infusion in four rabbits from each of groups I and V. Spastic paraplegia occurred in five rabbits in group I, three in group II, and two in group III. Four rabbits in groups II and III, seven in group IV and all eight in group V showed complete recovery of neurological function. The infusion of 3 degrees C solution achieved significantly lower spinal cord temperatures in group V after aortic clamping, compared with the temperatures in group I (P < 0.001-0.005). It was concluded that protection against spinal cord ischaemia and prevention of postoperative paraplegia are promoted as the temperature of the hypothermic infusion solution is lowered.

Endoscopic ligation of gastric varices using a detachable snare

A new technique of endoscopic treatment for gastric varices is presented here, which was applied in 10 patients, either electively (n = 9) or as emergency therapy for bleeding (n = 9) or as emergency therapy for bleeding (n = 1). A detachable snare is placed endoscopically, tightened around the varix, and then detached using a similar principle to that of band ligation. Following one or two treatment sessions (one snare applied in seven cases, two snares applied in three cases), eradication of gastric varices was observed in all patients. No significant complications were encountered, and nine of 13 snares passed spontaneously, the remaining ones being removed when found during follow-up endoscopy. Short-term follow-up (4-12 months, mean: 7.2 months) did not show either reappearance of varices or rebleeding in any of the patients. Angiography and endoscopic ultrasonography performed in four patients before and after treatment showed regression or disappearance of intramural vessels. Further studies will show the relative value of this new technique compared to other treatment modalities such as banding or cyanoacrylate injection.

Superficial-type adenomas and adenocarcinomas of the colon and rectum: a comparative morphological study

BACKGROUND/AIMS

It has been uncertain whether colorectal carcinomas preferentially arise on preexisting adenomas or de novo. However, from a morphological viewpoint, it seems unlikely that pedunculated or exophytic malignant polyps progress to the deeply ulcerated advanced carcinomas usually found clinically.

METHODS

The morphological features of 26 nonpolypoid, superficial-type colorectal tumors (17 adenomas and 9 adenocarcinomas) were compared to clarify the developmental route of colorectal carcinomas.

RESULTS

The adenomas and adenocarcinomas were very similar in size and gross appearance; however, examination of the surface appearances of unsectioned tumors by dissecting microscopy was helpful for distinguishing the two. Histologically, no adenomatous tissue was found in any case of superficial-type adenocarcinoma. Five of the nine adenocarcinomas, even including those of small size, invaded the submucosal layer, and two showed lymph node metastasis.

CONCLUSIONS

These findings suggest that superficial-type adenocarcinomas show rapid growth and aggressive behavior. We suggest that this type of carcinoma may not progress by the adenoma-to-carcinoma pathway but that it may arise from a very small superficial-type adenoma.

Effects of sex steroids on the proliferation of thymic epithelial cells in a culture model: a role of protein kinase C

Using a rat thymic epithelial cell line (TEC; IT-45R1), the present study attempted to elucidate the mechanism of action of sex steroid hormones (SH) on the proliferation of TEC. The findings were as follows: (a) the proliferation of TEC in response to SH was mediated through protein kinase C activity introduced as a result of interaction between SH and plasma-borne inhibitors; (b) the strong inhibitory effect of SH on TEC proliferation might be mediated through the SH receptor pathway because the proliferative response was triggered by progesterone (P) and androgen (A), whereas the inhibitory response was triggered by P, A and oestrogen. These results clearly suggest that the control of TEC proliferation is a 'shut-off' mechanism triggered by high plasma levels of SH. This further refers to the speculation that the development of the normal thymus may be due to a lack of this 'shut-off' mechanism so that development occurs at the adequate plasma SH levels that are often observed before puberty. However, this development is inhibited at the high plasma SH levels after puberty and/or during pregnancy.

[Cytofluorometric DNA analysis in different histological patterns of thyroid papillary carcinoma]

Some papillary carcinomas of thyroid glands contain not only typical papillary structures but also various histological features in the same tumor. To investigate how areas with variable histological features differ in proliferative activity and how these differences influence the biological behavior of the whole tumor, we measured DNA contents by cytofluorometry in six papillary carcinomas with different histological features in the same tumor. DNA ploidy patterns were determined and the percentage of S plus G2M phase cells (S + G2M fraction) was calculated only in diploid tumors to assess the proliferative activity. The following conclusions were drawn. 1) It was demonstrated that there were differences in proliferative activity among areas with variable histological features in 4 of six tumors. 2) In the tumors which invaded adjacent tissues, the proliferative activity of the invasive area tended to be higher than that of the original area of the tumor. Therefore, the possibility exists that more precise evaluation of the biological behavior of the tumor can be obtained by measuring DNA contents of the tumor cells in invasive areas. 3) There was the gap in S + G2M fractions among some tumors with the same histological differentiation. Accordingly, DNA analysis of tumors would be of value in estimating proliferative activity.

Mitogen-activated protein kinase and its activator are regulated by hypertonic stress in Madin-Darby canine kidney cells

Madin-Darby canine kidney cells behave like the renal medulla and accumulate small organic solutes (osmolytes) in a hypertonic environment. The accumulation of osmolytes is primarily dependent on changes in gene expression of enzymes that synthesize osmolytes (sorbitol) or transporters that uptake them (myo-inositol, betaine, and taurine). The mechanism by which hypertonicity increases the transcription of these genes, however, remains unclear. Recently, it has been reported that yeast mitogen-activated protein (MAP) kinase and its activator, MAP kinase-kinase, are involved in osmosensing signal transduction and that mutants in these kinases fail to accumulate glycerol, a yeast osmolyte. No information is available in mammals regarding the role of MAP kinase in the cellular response to hypertonicity. We have examined whether MAP kinase and MAP kinase-kinase are regulated by extracellular osmolarity in Madin-Darby canine kidney cells. Both kinases were activated by hypertonic stress in a time- and osmolarity-dependent manner and reached their maximal activity within 10 min. Additionally, it was suggested that MAP kinase was activated in a protein kinase C-dependent manner. These results indicate that MAP kinase and MAP kinase-kinase(s) are regulated by extracellular osmolarity.

[Rheumatoid arthritis terminating in multiple myeloma]

A 65-year-old woman with a 25-year history of rheumatoid arthritis (RA) was admitted because of acute pneumonia in January, 1991. Then she was pointed out M proteinemia (IgG 3,220 mg/dl, IgA 139 mg/dl, IgM 216 mg/dl) for the first time. Serum IL-6 was below 4.0 pg/ml. She was followed up because of lack of bone change. Plasma cell count in bone marrow were 14.6%. She was re-admitted because of development of bone lesions March, 1992. There was no joint pains, and serum IgG, IgA and IgM were 5,148 mg/dl, 114 mg/dl and 106 mg/dl, respectively. CRP was negative. Serological tests of rheumatoid factor and antinuclear antibody were both positive. Serum IL-6 was elevated to 14.8 pg/ml. Bone marrow aspiration disclosed 30.6% myeloma cells. Serum IgG, A, and M were 5,148 mg/dl, 114 mg/dl and 106 mg/dl, respectively. Serum immunoelectrophoresis showed monoclonal IgG with kappa type light chain. X-ray findings revealed radiolucent myelomatous foci. From these findings, IgG kappa-type multiple myeloma with RA was diagnosed.

Scanning electron microscopic observations of the vascular structure of vertebral end-plates in rabbits

We used scanning electron microscopy to examine the microcirculation in the vertebral end-plates of rabbits. The arteriola arborizes and swells at the end-plate and then coils to make a microvessel loop. This loop is the structure we refer to as a vascular bud. We suggest that these loop structures of the capillaries play a major role in the nutrition of the intervertebral discs.

[Effect of dopamine and prostaglandin E1 on portal venous oxygenation]

We evaluated the effects of dopamine (DA) and PGE1 on portal venous oxygenation in patients undergoing gastrectomy. Thirty-two patients studied were anesthetized with isoflurane and nitrous oxide in oxygen. They were divided into three groups: DA was infused at a rate of 3 micrograms.kg-1.min-1 in 10 patients (DA group), PGE1 was infused at a rate of 0.02 microgram.kg-1.min-1 in 10 patients (PGE1 group), and the remainders did not receive DA nor PGE1 (control group). There were no significant differences in PaO2 and SaO2 among three groups. However, portal venous PO2 and SaO2 in DA and PGE1 group were significantly higher than those in the control group. These results suggest that DA and PGE1 elevate the portal venous PO2 and SO2 by increasing splanchnic blood flow more than its oxygen uptake or without increasing splanchnic oxygen uptake, and increase the oxygen supply to the liver.

Hemagglutination activity of Lactobacillus acidophilus group lactic acid bacteria

The cells of 28 strains of the Lactobacillus acidophilus group were evaluated for hemagglutination (HA) activity. The activity was found in the surface layer (SL) protein fraction extracted by 2 M guanidine hydrochloride. The most SL proteins from the A group strains (L. acidophilus (A1), L. crispatus (A2), L. amylovorus (A3), and L. gallinarum (A4)) showed HA activity, but the proteins from the B group strains (L. gasseri (B1) and L. johnsonii (B2)) showed no activity. The SL proteins from the A group strains were composed in common of a main component having molecular mass of about 40-45 kDa on SDS-PAGE. The SL proteins from JCM 1034 strain that showed the highest HA activity was fractionated by CM-Toyopearl ion-exchange chromatography. The highest HA activity was detected in the major protein of 41 kDa. This protein was purified and shown to be composed of about 50% of hydrophobic amino acids. The HA activity of the protein (1034 lectin) was specifically inhibited by fetuin and bovine lactoferrin at the concentrations of 80 and 160 micrograms/ml, respectively. The removal of N-acetylneuraminic acid from fetuin significantly decreased the inhibitory activity.

[Ventricular septal perforation following acute myocardial infarction in an 85-year-old woman]

An 85-year-old woman who experienced sudden severe chest and back pains was admitted to our hospital. On admission a pansystolic murmur was audible and the ECG showed an acute antero-septal myocardial infarction. Right heart catheterization revealed increased oxygen from the right atrium to the right ventricle, leading to the diagnosis of ventricular septal perforation (VSP). Hemodynamics of the patient were stabilized using only a low dosage of dopamine. However the heart weakened progressively, an operation was performed on the 13th day after the onset of the perforation. The post-operative course was uneventful. She is the oldest patient with VSP which has been successfully operated in Japan.

A new UV-sensitive syndrome not belonging to any complementation groups of xeroderma pigmentosum or Cockayne syndrome: siblings showing biochemical characteristics of Cockayne syndrome without typical clinical manifestations

We report here on two siblings who show no clinical manifestations except for slight cutaneous photosensitivity and cutaneous pigmentation but have biochemical characteristics of Cockayne syndrome (CS). Fibroblasts derived from the patients (Kps2 and Kps3) were 3-4 times more sensitive to UV than normal cells. Although unscheduled DNA synthesis (UDS) in these cells was at a normal level, recovery of RNA synthesis (RRS) after UV irradiation was severely depressed. Microinjection of bacteriophage T4 endonuclease V into the cells corrected RRS after UV irradiation to a level near normal. These results indicate that DNA repair of cyclobutane-type pyrimidine dimers is impaired in the cells and the biochemical characteristics are similar to those of CS cells. However, cell fusion complementation tests with CS group A and B cells resulted in correction of RRS after UV irradiation. Cell fusion with XP group A, B, D, F and G cells also corrected RRS after UV irradiation, and microinjection of cell extracts prepared from Kps3 cells corrected UDS in XP group C and E cells, indicating that the patients do not belong to any complementation group of XP or CS. These results suggest that the patients have a new UV-sensitive syndrome with a biochemical phenotype of CS.

Assessment of the pathological grade of astrocytic gliomas using an MRI score

To evaluate the usefulness of an MRI score for identifying tumour tissue characteristics, 41 histologically verified supratentorial astrocytic gliomas, including 13 low-grade astrocytomas (LGA) 14 anaplastic astrocytomas (AA) and 14 glioblastoma multiformes (GBM), were examined with a 0.5T superconductive MR imager. Nine MRI criteria were used: heterogeneity (HET), cyst formation or necrosis (CN), haemorrhage (HEM), crossing the midline (CM), oedema or mass effect (EM), border definition (BD), flow void (FV), degree (CE-D) and heterogeneity (CE-HET) of contrast enhancement; Gd-enhanced T1-weighted images were obtained in 32 cases (10 LGA, 10 AA, and 12 GBM). Each of the criteria was scored and analysed statistically. The mean values of LGA, AA and GBM were 0.45 +/- 0.31, 1.18 +/- 0.20, and 1.47 +/- 0.22, respectively. The MRI score increased with the pathological grades (P < 0.01-0.001). LGA had significantly lower values than AA in five (HET, CN, EM, BD, CE-D) of the nine criteria (55.6%) and lower values than GBM in all except HEM (88.9%). Three criteria (33.3%): HET, CN, and FV were significantly higher in GBM than AA. CE-D, HET, EM, CN, and CE-HET proved to be related to the pathological grade by a multiple regression analysis (P < 0.001).

Resection of aortic aneurysms without aortic clamp technique with the aid of hypothermic total body retrograde perfusion

Aneurysms involving either the aortic arch or the proximal descending thoracic aorta in five patients were resected with the aid of profound hypothermic total body retrograde perfusion. Traditional surgical management of the aortic arch and the descending thoracic aorta necessitates clamping of the aorta. However, this technique may be associated with rupture or atheroembolism. Rupture occurring at the clamping site may be difficult to repair. Atheroembolism to the brain compromises the neurologic system, and multiple organ embolism is associated with disseminated intravascular coagulopathy. Atheroembolism in cardiovascular surgery has become increasingly prevalent. It is necessary to prevent clamp injuries and to preserve the function of the vital organs, such as the brain, heart, and liver, during aortic reconstruction. We applied a total body retrograde perfusion technique to operations for aortic aneurysms. Total body retrograde perfusion consists of cerebral protection by continuous perfusion through the superior vena cava, intermittent retrograde coronary perfusion through the coronary sinus, and continuous abdominal visceral perfusion through the inferior vena cava. It can yield a relatively bloodless operating field without the need for aortic clamping. We believe this new adjunct offers excellent results in the surgical treatment of aneurysms of the aortic arch or adjacent structures.

Protection against ischemic spinal cord injury: one-shot perfusion cooling and percutaneous topical cooling

PURPOSE

We investigated the protective effect of two methods of hypothermia against ischemic spinal cord injury: one-shot perfusion cooling and percutaneous topical cooling.

METHODS

Twenty-five rabbits were divided into five equal groups. The abdominal aorta was isolated proximally by a vascular clamp and distally by an inflated balloon catheter for 60 minutes. Group I served as control. In groups II (2.5 ml/min) and III (5.0 ml/min), hypothermic lactated Ringer's solution was infused for 3 minutes from the distal end of the catheter. Ice blocks were placed behind the backs of rabbits 30 minutes before ischemia in group IV. Group V underwent the procedures combined with those in groups II and IV (infusion of hypothermic solution plus placement of ice blocks). Another 15 rabbits underwent laminectomy at the L2 or L3 level. A temperature probe was inserted into the spinal cord to monitor cord temperature continuously during the procedures in all five groups (three rabbits per group).

RESULTS

Neurologic status on the second postoperative day in groups IV and V was significantly superior to that in group I (p < 0.01), but the neurologic status of groups II and III did not differ significantly from the neurologic status of group I. The spinal cord temperature in groups II and III dropped rapidly with the infusion, but it rose again quickly. In contrast, the spinal cord was kept sufficiently hypothermic during ischemia in groups IV and V.

CONCLUSIONS

We concluded that the percutaneous cooling method can keep the spinal cord sufficiently hypothermic during ischemia to lead to a significantly superior neurologic outcome.

Assessment of bromodeoxyuridine-labeled S-phase cells in experimentally induced precancerous lesions in the rat's tongue

Precancerous lesions and early invasive carcinomas were produced in the tongues of rats by oral administration of 0.001% 4-nitroquinoline 1-oxide in drinking water. The distribution and densities of S-phase cells were then studied in an attempt to clarify the mechanism of carcinogenesis from the viewpoint of cell cycle. Bromodeoxyuridine (BrdU)-labeled S-phase cells were demonstrated by an indirect peroxidase method, using anti-BrdU monoclonal antibody, and their percentage was determined as the labeling index (LI). The average BrdU LI was significantly higher in the precancerous lesions than in the normal epithelium. There was a wide range of LI found in cells showing such changes as hyperplasia, hyperparakeratosis, dysplasia and papilloma, but the differences among them were not significant. These findings also showed that there could be considerable differences in proliferative activity among lesions of the same grade, while the difference in histology did not mean a difference in proliferative activity. Additionally, many BrdU-labeled cells were seen in a few layers over the basement membranes of non-cancerous lesions immediately adjacent to early invasive carcinoma, suggesting that these layers had a higher possibility for advancing to early invasive carcinoma.

No enhancement by nitric oxide of glutamate release from P2 and P3 synaptosomes of rat hippocampus

Effects of nitric oxide on glutamate (Glu) release in long-term potentiation (LTP) were investigated by superfusion of conventional (P2) and large (P3) synaptosomes prepared from the rat hippocampus. Basal releasing rates of endogenous Glu from P2 and P3 fractions were 103.6 and 85.2 pmol/min/mg protein, respectively. Exposure to a depolarizing concentration of KCl (30 mM) evoked 3.58- and 4.52-fold increases in releasing rates of Glu from P2 and P3 fractions, respectively. Although the perfusion with sodium nitroprusside (NP, 10(-3) M), a nitric oxide-releasing agent, failed to augment the K(+)-evoked releases of Glu from P2 and P3 synaptosomes, NP enhanced that from slices of the hippocampus by 39% without changing basal release. Similarly, 8-bromoguanosine 3':5'-cyclic monophosphate (10(-4) M) increased the K(+)-evoked release of Glu from slices by 30%, but not from either synaptosomes. When synaptosomes were prepared from the hippocampus which was pretreated with two trains of electrical field stimulation (100 Hz, 0.1 ms, for 2 s), K(+)-evoked releases of Glu from P2 and P3 synaptosomes were increased by 15% and 23%, respectively. Although nitric oxide is postulated to function as a retrograde messenger to maintain LTP, present results suggest that nitric oxide may not directly act upon nerve terminals to enhance glutamate release, but that interventions of glias and short neurons may be involved in the presynaptic mechanism of LTP.

Effects of low-dose X-ray irradiation on biomembrane in brain cortex of aged rats

We previously found that low-dose X-ray irradiation or radon (weak alpha-ray) inhalation increases SOD activities and reduces lipid peroxide levels in various organs of 7-week-old rats or rabbits. In this study, we examined how the changes of SOD activity, lipid peroxide level, and membrane fluidity of the cerebral cortex in aged male Wistar rats (65 and 91 weeks old) were affected by low-dose X-ray irradiation (100 cGy or under) compared with those in 7-week-old rats, to elucidate the mechanism of aging inhibition. The following results were obtained: Although radiation sensitivity was observed to decreases with age, low-dose irradiation changed the Mn-SOD activity, lipid peroxide level, and membrane protein fluidity parameter of the cerebral cortex in the age rats to be closer to those in the youth. These findings suggest that the increased SOD activity induced by low-dose irradiation enhances biomembrane functions, and that the decrease of lipid peroxide level enhances the membrane protein fluidity.

[Contamination of healthy livestock with verocytotoxin producing Escherichia coli (VTEC), the first isolation from goats in Japan]

As part of the investigation on the source and route of infection with Verocytotoxin producing Escherichia coli (VTEC) in human beings, isolation of VTEC was attempted using fresh feces collected from healthy livestock (cattle, swine and goat) raised in Sagamihra, Yokohama and Hiratsuka cities from October, 1991 to March, 1992. VTEC could be isolated from 1 (1.0%) of 105 swine, 2 (3.6%) of 55 cattle and 2 (15.4%) of 13 goats. VTEC was isolated for the first time from goats in Japan. The combinations of the serotype and toxin type of the isolated strains were O116:H21 (VT2) and O163:H19 (VT2) for those isolated from the cattle, OUT:H19 (VT2vp) for that from the swine and OUT:H21 (VT1) for those from the goats. Since VTEC isolated from the cattle and goats were found to produce VT of the same serotypes as human VTEC, domestic animals were considered to be involved as a source of VTEC infection in human beings.

Detection of intrarenal venous invasions of malignant renal neoplasms by retrograde renal venography

The purpose of this study was to detect intrarenal venous invasion of malignant renal neoplasms not detected by other methods, with retrograde renal venography using a renal artery obstructing balloon. By this method, we studied 21 patients with malignant renal neoplasms, and clearly demonstrated the intrarenal branches up to the interlobar veins in all of these cases without any complications. This method detected small intrarenal venous lesions in three cases of renal cell carcinoma.

A rare portosystemic shunt detected by MRI and diagnosed by dynamic liver scintigraphy with Tc-99m phytate

Although various types of portosystemic shunts with portal hypertension have been widely reported, a collateral circulation near the pancreas head is rare. The authors report a case of a rare portosystemic shunt surrounding the pancreatic head, which was diagnosed by dynamic liver scintigraphy using Ikoma's scintigraphic criteria for the presence of portosystemic shunts. According to these criteria, abnormal accumulation of radioactivity at various abdominal sites (not identified on static images after the dynamic study) on 6 or more continuous frames of 5-second intervals (i.e., for 30 seconds or more after the arterial phase) indicates the presence of a portosystemic shunt. If liver scintigraphy is performed on a patient with portal hypertension, the dynamic study is valuable in the detection and diagnosis of a portosystemic shunt.

[A surgical treatment of ruptured arch aneurysm]

A 83-year-old woman was admitted to our hospital because of back pain and shock. Her chest X-ray and CT scan demonstrated a large arch aneurysm and hemothorax, suggesting ruptured aortic arch aneurysm. The ruptured aortic arch aneurysm was replaced with a woven Dacron graft under selective cerebral perfusion (SCP). Her postoperative course was uneventful without any neurological deficits. For the past three years, we have utilized SCP in 12 cases of arch aneurysms. There were three early deaths in this series. The cause of death were bleeding in one patient and cerebral accident in two patients. The latter two patients had severe atheromatous changes in the aortic wall. The SCP technique was a useful method of cerebral protection, especially for elderly patient with aortic arch aneurysm.