Localization of E-cadherin in peripheral glia after nerve injury and repair

Peripheral nerve injury results in histological and histochemical changes in neurons and glia. We have recently found that Ca(2+)-dependent cell adhesion molecule E-cadherin plays an important role in the selective fasciculation of a particular subset of unmyelinated sensory fibers. In the present immunohistochemical and immunoblot analyses, the temporal profile of the subcellular expression of this molecule in spinal nerves was examined after crushing, transecting, or ligaturing the sciatic nerve in mice with special attention paid to E-cadherin expression in glial cells. After axotomy of the sciatic nerve, distal axons of the proximal stump and the fibers of the distal stump degenerated, but E-cadherin was still detectable at the outer mesaxons of the myelinated axons as long as they remained morphologically intact. Subsequently, Schwann cells proliferated and migrated to form Schwann cell columns (Büngner's bands) as initial responses to denervation, and expressed E-cadherin at their site of contact with each other and later with sprouting axons. At the initial stage of myelin formation, slender processes of a single Schwann cell interdigitated with an enveloped axons, and expressed E-cadherin at the contact site elaborated by a single Schwann cell. Immunoblot analysis on day 7 revealed that E-cadherin was detected in both the proximal nerve segments and the regenerative distal segments, but was negative in the degenerative distal segments. On the basis of present data, it is suggested that E-cadherin might be involved in the stabilization of the peripheral glial network which provides the guidance of sprouting axons and myelination.

Risks in using siphon-reducing devices in adult patients with normal-pressure hydrocephalus: bench test investigations with Delta valves

To elucidate the reason for malfunction of Delta valves in patients with normal-pressure hydrocephalus, the authors applied a new concept of the bench test and simulated intracranial pressure (ICP) to measure the resultant flow with a complete shunt system. Subcutaneous pressure on the valve, valve implantation site, and postural hydrostatic differential-pressure changes were simulated in this bench test designed for adult patients with normal-pressure hydrocephalus. Subcutaneous pressure ranged within 6.4 +/- 0.09 cm H2O (mean +/- standard deviation) on the 7th day after the implantation of the valve in rats. A linear correlation between valve closing pressures and the external pressure was observed: gradual increase of the latter resulted in an approximately equal rise in the closing pressure. Closing pressure ranged within the physiological variation of ICP (10 +/- 5 cm H2O) in the supine position. In the erect position it was higher than the physiological variation (+5 to -5 cm H2O) when the valve was placed at the level of the foramen of Monro and lower when placed at the level of the clavicle. This observation indicates that the subcutaneous pressure around the Delta valve significantly affects its closing pressure. An excessive reduction of flow or a functional obstruction occurs when the patient with a Delta valve implanted at the foramen of Monro assumes an erect posture. The authors conclude that Delta valves are not recommended for implantation at the level of the foramen of Monro in patients with normal-pressure hydrocephalus because of the risk of underdrainage. The mastoid process or clavicle may be the alternative levels for its implantation to prevent underdrainage; however, the possibility of shunt malfunction should be kept in mind because subcutaneous pressure is variable among patients and that might affect the performance characteristics of these valves.

Vascular endothelial growth factor suppresses C-type natriuretic peptide secretion

Angiogenesis plays a pivotal role not only in wound healing and tumor progression but also in diabetic angiopathy, arteriosclerosis, and collateral formation of obstructive vascular diseases. Vascular endothelial growth factor (VEGF) is now thought to be an endothelium-specific and potent angiogenic factor. We previously demonstrated that C-type natriuretic peptide (CNP), originally isolated from porcine brain, is produced by endothelial cells and proposed that CNP can exert control over vascular tone and growth as a local vascular regulator. In the present study, we examined the effect of VEGF on CNP secretion from endothelial cells using the specific radioimmunoassay for CNP we developed. VEGF (1 to 100 ng/mL) dose-dependently suppressed CNP secretion from cultured bovine endothelial cells, and 100 ng/mL VEGF suppressed endothelial CNP secretion to 28% of control levels (31.7 +/- 5.5 versus 8.9 +/- 0.8 fmol/mL, vehicle versus VEGF). VEGF also suppressed CNP mRNA expression in endothelial cells 9 hours after administration. In contrast, basic fibroblast growth factor (20 ng/mL), an endothelium-nonspecific angiogenic factor, significantly stimulated CNP secretion by 290%. These results indicate that VEGF can regulate vascular tone and growth in the process of angiogenesis through suppression of endothelial secretion of CNP, which is an endothelium-derived vasorelaxing and growth-inhibitory peptide.

Immunohistochemical analysis of bcl-2 and p53 protein in breast carcinoma

We analyzed the expression of bcl-2 and p53 in relation to clinicopathological features and estrogen receptor (ER) status in breast carcinomas from a series of 67 women who were treated surgically. Fifty and 23 cases showed positive immunostaining for bcl-2 and p53 protein, respectively. Thirty-five cases were ER-positive. A positive relationship was observed between bcl-2 and ER (p<0.05). Furthermore, an inverse relationship was observed between bcl-2 and p53 (p<0.01), which suggests that overexpression of p53 may down-regulate bcl-2 expression in breast carcinoma tissue, as has been described in a breast carcinoma cell line.

A case of bronchopleural fistula detected by monitoring plasma endothelin-1

Levels of endothelin (ET)-1 peptide are transiently increased after major physical stress. While studying sequential changes in plasma ET-1 levels during various types of stress, we noticed that the level of plasma ET-1 began to rise 10 days post-operatively in one patient with lung cancer who had undergone a left lower lobectomy. 35 days postoperatively a bronchopleural fistula became clinically manifest. The case is presented and the use of plasma ET-1 as an indicator is discussed.

Synthesis and antitumor activities of 5'-O-aminoacyl-3'-O-benzyl derivatives of 2'-deoxy-5-fluorouridine and related compounds

Various O-alkyl derivatives of 2'-deoxy-5-fluorouridine (FUdR) were synthesized and their antitumor activities in mice bearing sarcoma 180 (s.c.-p.o.) were evaluated in terms of the ED50 values (mg/kg/d). Most of these compounds were superior to FUdR in antitumor activity. In particular, the antitumor activity of 3'-O-(p-chloro-benzyl)-FUdR (3e) (ED50 = 0.87 mg/kg/d) was as much as 100 times that of FUdR (ED50 = 84 mg/kg/d). Further, various 5'-O-aminoacyl derivatives of 3e were synthesized and evaluated in terms of ED50 value and therapeutic index (T.I.). Both the ED50 value (0.41 mg/kg/d) and the T.I. (4.18) of 3'-O-(p-chlorobenzyl)-5'-O-glycyl-FUdR hydrochloride (6a) were significantly improved, compared with those of 3e and FUdR. FUdR plasma concentration after a single p.o. dosing of 6a was maintained for as long as 24 h.

Traumatic atlanto-occipital dislocation with long-term survival

A 6-year-old boy presented with traumatic atlanto-occipital dislocation due to a traffic accident. Lateral spinal tomography showed anterior misalignment of the craniocervical junction. Magnetic resonance imaging demonstrated associated cervicomedullary injury. He underwent an occipital-cervical fusion with implantation of a spinal cord electrical stimulation unit. His consciousness level improved, but he remained quadriplegic and dependent on a respirator 2 years after the injury.

Progression in gastric carcinoma relative to the ratio of CD44 epithelial variant transcript to CD44 hematopoietic variant transcript

BACKGROUND

It has been suggested that CD44 splice variants play a role in the progression of certain epithelial cancers and non-Hodgkin's lymphoma. In this study, we investigated the epithelial variant/hematopoietic variant (E/H) ratio (the amount of the CD44 epithelial variant transcript relative to the CD44 hematopoietic variant transcript) in human gastric carcinoma compared with normal gastric mucosa.

METHODS

The ratio was determined for tumors and adjacent noncancerous mucosa from 30 gastric carcinoma patients using reverse transcription-polymerase chain reaction and Southern blotting. We also determined the tumor (T)E/H--noncancerous mucosa (N)E/H (the difference between E/H ratios of tumor tissue and adjacent noncancerous mucosa) and examined these measurements for correlations with the pathologic features of gastric carcinoma, as well as for their usefulness as an indicator of tumor progression.

RESULTS

The E/H ratio in tumor tissue was significantly higher than in adjacent noncancerous mucosa (P < 0.01). The TE/H--NE/H in patients with lymph node metastases was 0.16 +/- 0.11, compared with 0.07 +/- 0.08 in cases without lymph node metastases (P < 0.05). Significant correlations also were observed between the TE/H--NE/H and the depth of invasion, blood vessel invasion, and lymphatic vessel invasion (P < 0.03, P < 0.03, and P < 0.01, respectively).

CONCLUSIONS

Our results suggest that increases in the E/H ratio may be a useful indicator of progression in gastric carcinoma.

Clinicopathologic evaluation of immunohistochemical E-cadherin expression in human gastric carcinomas

BACKGROUND

E-cadherin plays a crucial role in cell-cell adhesion in epithelial tissues. Recent studies have shown a correlation between decreased E-cadherin expression and cancer cell detachment.

METHODS

The expression of E-cadherin was immunohistochemically analyzed using antihuman E-cadherin antibody in 121 cases of human gastric carcinoma.

RESULTS

In noncancerous areas, the epithelial cells, including those with intestinal metaplasia, were stained positively in the plasma membrane. In contrast, E-cadherin expression of the cancer cells varied from case to case in primary and secondary sites. Tumors with a decrease in E-cadherin occurred significantly more frequently in undifferentiated adenocarcinoma (P < 0.05) and scirrhous type (P < 0.01). The rate of E-cadherin-negative tumors was higher in patients with peritoneal metastasis (P < 0.01) or in those with distant lymph node metastasis (P < 0.01), though the tumors with liver metastasis had relatively positive E-cadherin expression. Patterns of initial recurrence had similar results. Reduction or loss of E-cadherin expression correlated with shorter survival in patients after curative operation regardless of stage of disease.

CONCLUSIONS

The decreased E-cadherin expression correlates with dedifferentiation, infiltrative tumor growth, distant metastasis, and poor survival for patients with gastric carcinoma. Thus, immunohistochemical study of E-cadherin may have clinicopathologic value for patients with gastric carcinoma.

Augmented expression of the endothelin-A receptor gene in cultured mesangial cells from stroke-prone spontaneously hypertensive rats

1. To elucidate the role of endothelin (ET) receptor in hypertension, we studied the expression of the ET-A receptor (ET-AR) gene and the ET-B receptor (ET-BR) gene in cultured mesangial cells isolated from stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto (WKY) rats. 2. The mesangial cells from both SHRSP and WKY expressed ET-AR predominantly. The level of the ET-AR mRNA in mesangial cells from SHRSP was 5-fold higher than that in the cells from WKY. The ET-BR mRNA in the mesangial cells from both strains was hardly detectable by northern blot analysis. 3. These results demonstrate that the expression of the ET-AR gene was markedly augmented in mesangial cells from SHRSP.

Endothelin-induced activation of mitogen-activated protein kinases in glomerular mesangial cells from normotensive and stroke-prone spontaneously hypertensive rats

1. Kinase assay in myelin basic protein (MBP) containing polyacrylamide gels revealed that endothelin-1 (ET-1) and ET-3 increased MBP kinase activities in glomerular mesangial cells (MC) from Wistar-Kyoto (WKY) rats and spontaneously hypertensive rat (SHRSP). ET-1 stimulated MBP kinase activities more potently than ET-3. 2. Immunoprecipitation with anti-41-kDa MAPK antiserum showed that the MBP kinases activated by ET-1 correspond to 43- and 41-kDa MAPK. 3. Since Phorbol 12-myristate 13-acetate, a direct activator of protein kinase C, also activated MAPK, protein kinase C was suggested to mediate ET-induced activation of MAPK. 4. These results suggest that MAPK may mediate the ET actions in glomerular mesangial cells from normotensive rats as well as spontaneously hypertensive rats. Since ET is produced by vascular endothelial cells of the kidney and glomerular mesangial cells, the ET signalling pathway may have some physiological and pathophysiological significance in vivo glomerulus.

Possible participation of autocrine and paracrine vascular endothelial growth factors in hypoxia-induced proliferation of endothelial cells and pericytes

Hypoxia is the principal factor that causes angiogenesis. These experiments were conducted to explore how it induces the proliferation of vascular cells, a key step in angiogenesis. Human umbilical vein endothelial cells and bovine retinal pericytes were grown in controlled atmosphere culture chambers containing various concentrations of oxygen. The numbers of both endothelial cells and pericytes increased significantly under hypoxic conditions; the O2 concentrations that achieved maximal growth promotion were 10% for endothelial cells and 2.5% for pericytes. Quantitative reverse transcription-polymerase chain reaction analysis revealed that mRNAs coding for the secretory forms of vascular endothelial growth factor (VEGF), a mitogen specific to endothelial cells, were present in both endothelial cells and pericytes and that their levels increased significantly in the two cell types as the atmospheric O2 concentration decreased. The two genes for VEGF receptors, kinase insert domain-containing receptor (kdr) and fms-like tyrosine kinase 1 (flt1), were found to be constitutively expressed in endothelial cells, and their relative mRNA levels were ranked in that order. On the other hand, only flt1 mRNA was detected in pericytes under hypoxic conditions. Furthermore, most antisense oligodeoxyribonucleotides complementary to VEGF mRNAs efficiently inhibited DNA synthesis in endothelial cells cultured under hypoxic conditions. These results indicate that autocrine and paracrine VEGFs may take part in the hypoxia-induced proliferation of endothelial cells.

Effects of cervical spinal cord stimulation on glucose consumption in patients with posttraumatic prolonged unconsciousness

The effects of cervical spinal cord stimulation (CSCS) on glucose consumption were examined in two patients with prolonged disturbance of consciousness due to head injuries. Several clinical parameters, including glucose consumption using positron emission tomography (PET) with [18F]2-fluoro-2-deoxy-D-glucose (FDG), were compared before and after CSCS. After a 4-month period of stimulation, one patient (Case 1) regained consciousness and began to speak, but the other patient (Case 2) showed no improvement in consciousness level. Computed tomography and magnetic resonance imaging showed Case 1 had no abnormalities in the thalamus and brainstem and no diffuse brain atrophy. Case 2 had a low density area in the left thalamus and enlargement of the aqueduct with diffuse atrophy of the left cerebral hemisphere. Cerebral blood flow studies and electrophysiological examinations revealed no remarkable change after CSCS. The PET study showed an increase in FDG uptake in the hypothalamus and the thalamus in both patients, but an increase in FDG uptake in the left cingulate gyrus and left frontal lobe was observed only in Case 1. These observations suggest that activation of the ascending reticular activating system, hypothalamus, thalamus, cingulate gyrus, and frontal cortex, and the preservation of the fiber connections between the limbic system and the thalamus and hypothalamus are important for CSCS treatment to improve the level of consciousness.

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

BACKGROUND

Several studies have revealed a correlation between sialosyl Tn antigen (STN) and certain clinicopathologic features of various cancers, and that STN is an independent prognostic factor. However, the clinical significance of the expression of STN in gastric cancer has not been reported. Thus, the purpose of this study was to evaluate immunohistochemically the clinical significance of expression of STN in gastric cancer.

METHODS

The expression of STN in surgically resected specimens of human gastric cancer was evaluated immunohistochemically using a monoclonal antibody (TKH-2), in 60 patients whose serum STN levels were measured and in 54 patients with advanced cancer who had been followed for more than 5 years after gastrectomy. The correlations between the level of STN expression and clinicopathologic factors were analyzed. The staining intensity was graded as follows: (-), less than 5% of the cancer cells expressed STN; (+), 5-50%; (++), more than 50%.

RESULTS

Sialosyl TN antigen staining was detected mainly on the cell membrane, in the cytoplasm, and in the luminal contents, and 57.2% of the 60 specimens expressed STN, whereas the corresponding value for positive serum levels was 15%. A higher percentage of advanced tumors expressed STN than did the early cases, but the difference was not statistically significant. All cases with strong staining, the (++) cases, were advanced cases either with lymph node metastases or with cancer invading in or beyond the muscle layer proper. The expression of STN appeared to be related to the clinical stage, the extent of cancer invasion, and the presence of lymph node metastases. Sialosyl TN antigen was detected in the serum in less than 6% of the patients whose tumors were (-) or (+) for STN expression, and in 86.7% of the patients whose tumors expressed high levels of STN (++). The estimated 5-year survival in advanced cases (Stage III) was significantly better in those with negative STN expression than in those with positive STN expression (P < 0.01).

CONCLUSIONS

These results suggest that STN may be a useful marker associated with the prognosis of patients with advanced gastric cancer.

A new approach for bronchoplastic procedures in the treatment of bronchial carcinoid tumors

Usually patients with typical carcinoid tumors originating in a segmental bronchus undergo segmentectomy with or without a bronchoplastic procedure. We have performed only sleeve resection of the bronchus for a bronchial carcinoid tumor located in the left basal bronchus thus preserving the lung tissue. This was made possible by transecting and reanastomosing the pulmonary artery.

Whole-cell analysis of NGK2 (mKv3.1a) K+ channels stably expressed in mouse fibroblast cells

NGK2 (mKv3.1a) K+ channel cDNA was introduced into mouse B82 fibroblast cells to express in a mammalian system. The NGK2 current in the stably transformed fibroblast cells exhibited a high threshold for activation and slow decay with two components. The data suggest that the NGK2 channel may contribute to slowly inactivating K+ currents observed in excitable and inexcitable cells.

Plasma endothelin-1 as a marker for doxorubicin cardiotoxicity

The use of doxorubicin is often limited by cardiotoxicity that can lead to congestive heart failure (CHF). Although various techniques have been used to predict its cardiotoxicity, none has proven useful. We reported 2 patients in whom the level of plasma endothelin (ET)-1 rose progressively during doxorubicin treatment of breast cancer, and who subsequently developed CHF. Accordingly, we conducted a prospective study of 30 consecutive patients, 23 with breast cancer and 7 with small-cell lung cancer, who were treated with doxorubicin. Serial changes in plasma ET-1 during doxorubicin treatment were measured by a specific radioimmunoassay, and plasma levels of atrial natriuretic peptide (ANP) were determined by a sensitive immunoradiometric assay. M-mode echocardiography was performed serially to monitor the fractional shortening (FS) and the left ventricular ejection fraction (LVEF). The plasma concentrations of ET-1 rose progressively in 5 of the 30 patients during doxorubicin treatment. Two of the 5 patients developed clinically overt CHF after developing cumulative doses of doxorubicin of 500 and 480 mg/m2. Serial measurement of plasma levels of ANP, FS and LVEF showed no abnormalities until the development of CHF. Another 25 patients who had received doxorubicin (cumulative doses ranging from 400 to 660 mg/m2) and had not developed CHF showed no appreciable change in plasma ET-1 or other markers. This prospective study suggests that plasma ET-1 may be useful for predicting the risk of doxorubicin-induced cardiotoxicity.

Basic fibroblast growth factor may repair experimental cerebral aneurysms in rats

BACKGROUND AND PURPOSE

To determine whether basic fibroblast growth factor (FGF) can induce proliferative response of endothelial cells and/or smooth muscle cells in aneurysmal lesions, we investigated the effect of the intravenous administration of basic FGF on experimental cerebral aneurysms.

METHODS

Cerebral aneurysms were induced in rats by ligation of the unilateral common carotid artery, producing hypertension. Three months later, basic FGF was intravenously injected in two groups of randomly divided rats on days 1, 3, and 5 at two different doses (low dose: 2 micrograms/100 g body wt per day; high dose: 5 micrograms/100 g body wt per day). In a control group, normal saline was similarly injected. The junctions of the anterior cerebral artery (ACA) and the olfactory artery (OA) were examined with a light microscope. Aneurysmal changes were defined as the lesions with discontinuity of the internal elastic lamina in more than half of the outward dilated wall. Depending on whether the smooth muscle cell layer was present in the whole wall, the lesions were divided into two stages: early aneurysmal lesion (whole area) and saccular aneurysm (not totally preserved).

RESULTS

The control and the low-dose groups presented no obvious intimal thickening in the intact ACA-OA junctions of both nonligated and ligated sides as well as in the aneurysmal changes. In contrast, in the high-dose group, various degrees of intimal thickening in the wall were detected in 7 of 15 early aneurysmal lesions (P = .019, Fisher's exact test). Immunohistochemistry showed the proliferated cells to be smooth muscle cells.

CONCLUSIONS

These results demonstrate that exogenous basic FGF induces the proliferative response of smooth muscle cells in aneurysmal lesions in rats.

Immunohistochemical alterations of fibronectin during the formation and proliferative repair of experimental cerebral aneurysms in rats

BACKGROUND AND PURPOSE

To determine whether distributional changes of fibronectin, a factor promoting wound healing, occur during the formation and repair of cerebral saccular aneurysms, we performed immunohistochemical analyses in experimental aneurysms.

METHODS

Cerebral aneurysms were induced in rats by both the ligation of the unilateral common carotid artery and induced hypertension. Intimal proliferation in aneurysmal walls was induced by the ligation of the preserved common carotid artery 3 months after the first operation. The distribution of fibronectin was examined by immunohistochemistry in anterior cerebral artery-olfactory artery bifurcations under the following three conditions: normal bifurcations in control rats, early aneurysmal lesions during the aneurysm induction, and aneurysmal lesions with intimal proliferation. Furthermore, the immunohistochemical distributions of type I and IV collagens were examined to evaluate the specificity of fibronectin immunoreactivity.

RESULTS

In the normal bifurcations, fibronectin was positive in the subintimal space, the surrounding area of the medial smooth muscle cells, and the adventitial fibrous tissue. In early aneurysmal lesions, linear staining of fibronectin and type I and IV collagens in the subendothelial space disappeared with the loss of the internal elastic lamina. In the intimal proliferation of early aneurysmal lesions, fibronectin was strongly immunostained in the subendothelial space and diffusely immunostained in the widened extracellular space surrounding proliferated cells. In contrast, the stainings of type I and IV collagens were sparse or negative.

CONCLUSIONS

Although the present findings regarding dynamic changes of fibronectin distribution do not prove any causality in the process of aneurysm formation and repair, these immunohistochemical changes may constitute the crucial sequela of intimal endothelial damage and its subsequent recovery in cerebral aneurysms.

Effect of vagal autotransplantation and bifemelane hydrochloride on cholinergic markers and event-related potentials in rats with lesions of the nucleus basalis magnocellularis

In rats lesioned by injecting the ibotenic acid (8 micrograms/site) into the unilateral nucleus basalis magnocellularis (NBM), the effect of treatment with bifemelane hydrochloride (BIF) or autotransplantation of the vagal nodosal ganglion was studied electrophysiologically by serial measurement of the event-related potential (ERP, P300) for 4 weeks. In addition, the effects on cholinergic markers were assessed by determining the specific binding of [3H]QNB (quinuclidinyl benzilate) to the muscarinic acetylcholine receptor (mAChR) as well as the activity of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE). The P300 latency was delayed and its amplitude remained low for 4 weeks in NBM-lesioned rats. In contrast, a return to normal occurred after 2-3 weeks in rats given daily intraperitoneal injections of BIF (15 mg/kg) and in autotransplanted rats. In lesioned rats, the cortical ChAT and AChE activities on the affected side did not recover, but the postsynaptic receptor response was transiently activated soon after lesioning. BIF increased specific mAChR binding (an early increase of affinity and a subsequent increase of receptor density) as well as presynaptic ChAT activity. Transplantation achieved the early activation of mAChR binding (increased receptor density) and continuously increased ChAT activity. Thus, the postsynaptic compensatory receptor mechanism of denervation supersensitivity acted as an early response to the depression of presynaptic cholinergic activity, but it could not improve the P300 response until the subsequent increase of cortical ChAT activity. Improvement of P300 combined with cortical cholinergic recovery after nodosal ganglion grafting or administration of BIF suggests that the neocortical ACh level may play an important role in regulating ERP.

Aphidicolin-sensitive DNA polymerase is incorporated into the chromatin during nuclear envelope assembly in Xenopus egg extract

The mechanism for incorporation of aphidicolin-sensitive DNA polymerase into reconstituting sperm nuclei was studied in a Xenopus egg extract cell-free system. Aphidicolin-sensitive DNA polymerase activity was sedimented along with the light membrane fraction of Xenopus egg extract on a discontinuous sucrose gradient. Treatment of the egg extract with Triton X-100 caused DNA polymerase activity to migrate to a lighter density position at which free proteins were distributed. DNA polymerase activity was incorporated into the reconstituting sperm nuclei from the egg extract, but no nuclear incorporation was observed in nuclei incubated in egg extracts which had been treated with Triton X-100 or sonicated. The incorporation was also prohibited by several different treatments of the egg extract resulting in incomplete assembly of the nuclear membrane on the sperm nuclei. On the other hand, there was no inhibition of nuclear incorporation into the sperm nuclei reconstituting in the extracts which had been depleted of WGA-binding pore complex proteins or which contained a specific inhibitor of topoisomerase II (ICRF-193). In these two cases, the nuclear double-layered membrane assembled normally, although in the former case the sperm nuclei lacked lamina and did not initiate DNA replication, and in the latter case the sperm nuclei did not decondense but initiated DNA replication. Thus, it is concluded that DNA polymerase activity is incorporated into the reconstituting nuclei via the membraneous/particulate fraction of the egg extract simultaneously with nuclear double-layered membrane assembly. The lamina assembly and the transport system via the nuclear envelope pore complex are suggested not to participate in DNA polymerase nuclear incorporation.

Multicentric infantile myofibromatosis in the cranium: case report

Infantile myofibromatosis is a rare clinical entity characterized by multiple mesenchymal tumors in the neonatal period. We describe a 15-month-old girl with multicentric cranial lesions involving the parietal and occipital bones associated with a single small subcutaneous lesion in the back. Magnetic resonance imaging clearly demonstrated the isointense lesions on T1-, T2-, and proton density-weighted images, which showed marked gadolinium enhancement of the tumors and adjacent dura mater. A histological examination of the resected temporal lesion revealed the myofibroblastic nature of the tumor cells. This is the first description of magnetic resonance features of multicentric infantile myofibromatosis in the cranium, and gadolinium-enhanced magnetic resonance images were useful in showing dural involvement. The importance of recognizing this disorder is emphasized because of its special clinical behavior.

Prognostic significance of three novel biologic factors in a clinical trial of adjuvant therapy for node-negative breast cancer

BACKGROUND

Five products of human breast carcinoma cells, including membrane-associated phospholipase A2 (M-PLA2), polymorphonuclear leukocyte elastase (PMN-E), tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA), and endothelin-1 (ET-1), have been implicated in the processes of tumor cell invasion and metastasis in human breast carcinoma. However, the prognostic significance of these factors has not been assessed previously in node-negative breast carcinoma, in which adjuvant treatment is dependent on risk stratification.

METHODS

The five products of breast carcinoma cells were measured in 184 patients with node-negative breast carcinoma who were enrolled in the Kumamoto Adjuvant Chemo-Endocrine Therapy for Breast Cancer prospective randomized trial, and the predictive values of these factors for relapse-free and overall survival were evaluated.

RESULTS

M-PLA2, PMN-E, and t-PA were found to be significant independent predictors of relapse-free and overall survival, whereas u-PA and ET-1 were not independently predictive. Further statistical analyses showed that the predictive powers of M-PLA2, PMN-E, and t-PA were additive. A combination of these three factors identified a group of patients (approximately 50% of those who manifested node-negative breast carcinoma) with a favorable prognosis, regardless of the administration of adjuvant therapy.

CONCLUSIONS

This study identified three biologic factors that are valuable predictors of survival in node-negative breast carcinoma. A combination of these biologic factors may allow identification of low-risk patients who could be spared adjuvant therapy.

In vivo and in vitro evidence for ATP-dependency of P-glycoprotein-mediated efflux of doxorubicin at the blood-brain barrier

We investigated the role of ATP in the active efflux of doxorubicin (DOX) mediated by P-glycoprotein (P-gp), the multidrug-resistance (MDR) gene product, at the blood-brain barrier. In transient brain ischemic rats prepared with 4-vessel occlusion of vertebral and common carotid arteries for 20 min, a procedure that depleted their brain ATP content to 3% that of normal rats, the estimated permeability coefficient of DOX was increased 17-fold (to 243 +/- 2.5 microL/min/g brain). When the ATP content recovered to a normal level by means of 30-min and 24-hr cerebral recirculation of blood, the permeability coefficient recovered to 14.0 +/- 5.0 and 18.4 +/- 2.3 microL/min/g brain (mean +/- SEM, N = 3-6), respectively, very close to the control permeability (14.3 +/- 1.5 microL/min/g brain). The uptake of DOX by primary cultured brain capillary endothelial cells expressing P-gp at the luminal membrane was increased significantly (up to 2-fold), which correlated well with the decrease of cellular ATP contents caused by treating the cells with metabolic inhibitors. Evidence for the ATP-dependent transport of DOX obtained from the present in vivo and in vitro studies strongly indicates that P-gp in the brain capillaries functions actively as an efflux pump in the physiological state, providing a major mechanism to restrict the transfer of DOX into the brain.

[Study on the anti-dementia therapies for rats with a unilateral basal forebrain lesion--serial changes of the cholinergic markers' activities and event-related potentials after the administration of bifemelane hydrochloride or autotransplantation of the vagal nodosal ganglion]

Using rats with a unilateral lesion in the nucleus basalis magnocellularis (NBM), we examined electrophysiologically the therapeutic effects of bifemelane (BIF) and autotransplantation of the vagal nodosal ganglion (X) on the event-related potential (P300) serially for 4 weeks, and also neurochemically their effects on cholinergic markers--the specific binding of 3H-QNB (quinuclidinyl benzilate) on muscarinic acetyl-choline receptor (mAChR) and the activities of acetylcholinesterase (AChE) and choline acetyltransferase (CAT). The latency of P300 was continuously delayed and its amplitude remained low voltage until 4 weeks in the NBM-lesioned rats (No-Tx group). Whereas the latency and amplitude returned to normal after 2-3 weeks in the rats given daily intraperitoneal injection of 15 mg/kg BIF (BIF group) and autotransplanted ones (X group). The cortical CAT and AChE levels on the lesion side did not recover until 4 weeks in No-Tx group, but the CAT levels recovered after 3 weeks in both BIF and X group; the AChE levels, after 1 week in BIF group and after 3 weeks in X group. The cortical mAChR on the lesion side was within or more than normal range in all rats. These results might indicate as follows: 1) Compensatory postsynaptic process such as cortical mAChR increase and AChE decrease occurred after acute cholinergic depletion. 2) Administration of BIF and X autotransplantation recovered cortical CAT and AChE levels and normalized cholinergic neuronal activity of P300.

Tissue-type plasminogen activator predicts endocrine responsiveness of human pancreatic carcinoma cells

BACKGROUND

Estrogen receptor (ER) has been found in human pancreatic carcinoma, but the potential benefit of endocrine therapy never has been assessed adequately. The aim of this study was to determine whether the presence of ER can be used as an indicator of hormone responsiveness, and whether modulation of tissue-type plasminogen activator (t-PA) by ER can identify hormone-responsive pancreatic carcinomas.

METHODS

The authors investigated ER status and hormonal regulation of t-PA in nine human pancreatic carcinoma cell lines, AsPC-1, BxPC-3, Capan-1, Capan-2, Hs-700T, Hs-766T, MiaPaCa-2, PANC-1, and SUIT-2. Furthermore, to examine whether estrogen dependency of t-PA production in pancreatic carcinoma cells correlated with responsiveness to endocrine therapy, the in vivo effects of various endocrine agents on the growth of the nine pancreatic cell lines transplanted into nude mice were examined.

RESULTS

In a 17 beta-estradiol (E2)-binding assay, three of the nine pancreatic carcinoma cell lines (BxPC-3, Capan-2, and MiaPaCa-2) contained measurable levels of estradiol binding sites in vitro and in vivo using tumors transplanted into nude mice. Although t-PA was present in the culture medium in eight of the nine pancreatic carcinoma cell lines (not in Hs-700T), t-PA production was regulated by estrogen via an ER system in vitro only in the Capan-2 cell line. E2 injection into tumor-bearing mice showed acceleration of tumor growth only in Capan-2 tumors. Administration of a competitive ER antagonist, toremifene, and a luteinizing hormone-releasing hormone analogue, leuprorelin acetate (LEU), to Capan-2-bearing mice significantly reduced the rate of tumor growth, although there was no actual shrinkage of tumor mass. These agents failed to exert any antitumor effect on the other eight pancreatic cell lines. Although aromatase inhibitors, CGS 20267 and vorozole did not modify the in vivo growth of the nine pancreatic carcinoma cell lines significantly, the combined use of aromatase inhibitors with LEU exhibited a synergistic antitumor effect on Capan-2-bearing mice. Medroxyprogesterone acetate treatment significantly reduced the tumor volume of Capan-2 and also caused delayed growth in two other cell lines, AsPC-1 and MiaPaCa-2.

CONCLUSIONS

The estrogen dependency of t-PA production may clarify the functional state of ER in human pancreatic carcinoma cells. This finding may aid in planning endocrine therapy for patients with this lethal cancer.

[A strong predictor of breast cancer--hepatocyte growth factor (HGF)]

We measured the hepatocyte growth factor (HGF) concentration in breast cancer tissue extracts and evaluated its association with survival. The HGF level was found to be the most important factor in survival, even more so than lymph node involvement. HGF may play an important role in the progression of human breast cancer.

ICRF-193, an inhibitor of topoisomerase II, demonstrates that DNA replication in sperm nuclei reconstituted in Xenopus egg extracts does not require chromatin decondensation

A bis(2,6-dioxopiperazine) derivative, ICRF-193, is a specific inhibitor of topoisomerase II without cleavable complex-stabilizing activity. In Xenopus egg extract containing ICRF-193, demembranated sperm head chromatins were inhibited from decondensation. However, nuclear envelope-lamina assembled on the inhibited chromatins. The nuclear envelope-lamina continued to expand even after loss of contact with the chromatin surface. On the other hand, semiconservative DNA replication was initiated as soon as the lamina was assembled onto the surface of condensed chromatin, though the initiation was retarded and its extent was reduced, compared with that in noninhibited chromatins. Thus, it is concluded that topoisomerase II activity is not required for the formation of active DNA replication clusters and the extension of nuclear envelope-lamina on the chromatin, while the nuclear envelope-mediated decondensation of sperm chromatins is dependent on topoisomerase II activity.

Occipital dermal sinus associated with dermoid cyst in the fourth ventricle

MR was helpful in demonstrating the spatial relationship between a dermoid cyst in the fourth ventricle and an occipital dermal sinus. T1-weighted images clearly showed the mixed hypointense mass in the fourth ventricle and above the vermis, which appeared to be connected to an occipital dermal dimple.

Tissue-type plasminogen activator predicts endocrine responsiveness of human pancreatic carcinoma cells

BACKGROUND

Estrogen receptor (ER) has been found in human pancreatic carcinoma, but the potential benefit of endocrine therapy never has been assessed adequately. The aim of this study was to determine whether the presence of ER can be used as an indicator of hormone responsiveness, and whether modulation of tissue-type plasminogen activator (t-PA) by ER can identify hormone-responsive pancreatic carcinomas.

METHODS

The authors investigated ER status and hormonal regulation of t-PA in nine human pancreatic carcinoma cell lines, AsPC-1, BxPC-3, Capan-1, Capan-2, Hs-700T, Hs-766T, MiaPaCa-2, PANC-1, and SUIT-2. Furthermore, to examine whether estrogen dependency of t-PA production in pancreatic carcinoma cells correlated with responsiveness to endocrine therapy, the in vivo effects of various endocrine agents on the growth of the nine pancreatic cell lines transplanted into nude mice were examined.

RESULTS

In a 17 beta-estradiol (E2)-binding assay, three of the nine pancreatic carcinoma cell lines (BxPC-3, Capan-2, and MiaPaCa-2) contained measurable levels of estradiol binding sites in vitro and in vivo using tumors transplanted into nude mice. Although t-PA was present in the culture medium in eight of the nine pancreatic carcinoma cell lines (not in Hs-700T), t-PA production was regulated by estrogen via an ER system in vitro only in the Capan-2 cell line. E2 injection into tumor-bearing mice showed acceleration of tumor growth only in Capan-2 tumors. Administration of a competitive ER antagonist, toremifene, and a luteinizing hormone-releasing hormone analogue, leuprorelin acetate (LEU), to Capan-2-bearing mice significantly reduced the rate of tumor growth, although there was no actual shrinkage of tumor mass. These agents failed to exert any antitumor effect on the other eight pancreatic cell lines. Although aromatase inhibitors, CGS 20267 and vorozole did not modify the in vivo growth of the nine pancreatic carcinoma cell lines significantly, the combined use of aromatase inhibitors with LEU exhibited a synergistic antitumor effect on Capan-2-bearing mice. Medroxyprogesterone acetate treatment significantly reduced the tumor volume of Capan-2 and also caused delayed growth in two other cell lines, AsPC-1 and MiaPaCa-2.

CONCLUSIONS

The estrogen dependency of t-PA production may clarify the functional state of ER in human pancreatic carcinoma cells. This finding may aid in planning endocrine therapy for patients with this lethal cancer.

Clear cell (glycogen-rich) meningioma with special reference to spherical collagen deposits

A detailed immunohistochemical and electron microscopic study of a case of clear cell (glycogen-rich) meningioma is presented. The neoplasm recurred three times and the patient died of the disease. The specimens obtained at all three operations showed similar basic histologic patterns. The tumor was comprised mainly of a syncytial, sheet-like proliferation of polygonal cells with clear cytoplasm containing abundant glycogen. The immunohistochemical features included epithelial membrane antigen- and vimentin-positive cytoplasm. The ultrastructural examination revealed distinctive meningocytic cells which contained large amounts of glycogen granules. In addition, the presence of numerous blocky, collagen conglomerations were a conspicuous feature of this tumor. The collagen deposits exhibited intensive immunopositivity for types I, III, IV and VI collagen, and their fine structure suggested the production of the extracellular matrix substance from the contiguous meningothelial cells with well developed Golgi complexes and frequent vesicles near the cell membrane. Proliferating cell nuclear antigen cell kinetics study revealed high labeling index of this neoplasm. The findings for this clear cell (glycogen-rich) meningioma may be useful in the differential diagnosis and treatment of this distinctive subtype of meningioma.

Free-form neutrophil elastase is an independent marker predicting recurrence in primary breast cancer

We have measured the immunoreactive neutrophil elastase (ir-NE) concentration in tumor extracts of 313 primary human breast cancers using an enzyme-linked immunosorbent assay recently developed and have evaluated its association with disease-free survival. This is a sensitive assay that enables rapid measurement of both free-form and alpha 1-proteinase inhibitor (alpha 1-PI)-complexed form of ir-NE. Breast cancer patients with high ir-NE concentrations had a significantly shorter disease-free survival (P = .013) than those with a low ir-NE concentration at the cutoff point of 9.0 micrograms/100 mg protein, which was determined in another group of 49 patients. In multivariate analysis, the ir-NE level was found to be an independent prognostic factor (relative risk = 2.2, P = .025) for disease recurrence in human breast cancer. Furthermore, when multivariate analysis was repeated with inclusion of each level of free-form and alpha 1-PI-complexed form, the former level was an independent predictor of recurrence (relative risk = 2.5, P = .015), whereas the latter was not independently predictive (P = .43). These results support the hypothesis that this enzyme may play an active role in the tumor progression that leads to metastasis in human breast cancer.

MR imaging of primary intracranial malignant lymphoma

Magnetic resonance imaging (MRI) was performed in ten patients with intracranial lymphoma. Seven were pathologically confirmed and three were clinically diagnosed. Nineteen lesions were found among the ten cases. None had acquired immunodeficiency syndrome (AIDS) or had received immunosuppression therapy. Two lesions were in the lateral and third ventricles, and the others were predominantly in the corpus callosum, deep white matter, or central gray matter. Four patients had multiple lesions. All had mild to severe edema. On T1-weighted images, all lesions showed hypointensity. On T2-weighted images, three lesions showed definite hypointensity to gray matter, and the others showed hyperintensity. The contour of all lesions was well demarcated from the surrounding edema. Eight cases were scanned before and after intravenous administration of 0.1 mmol/kg of gadolinium-dimethylene triaminepentaacetic acid (Gd-DTPA), and all exhibited homogeneous enhancement. Three cases showed blurred enhancement margins. Four cases showed hemorrhage, and the frequency of hemorrhage was higher than in previous reports. Pathological examination was performed in seven cases. All showed dense concentric lymphoma cells without necrosis. There was no pathological difference between the hyperintense and hypointense lesions on T2-weighted images.

Inducible nitric oxide synthase in a human glioblastoma cell line

Nitric oxide synthase (NOS) activity was induced in the cytosol of A-172 cells by treatment with lipopolysaccharide, tumor necrosis factor-alpha, and interferon-gamma. A 130-kDa human inducible NOS (iNOS) protein was detected with anti-rat iNOS antibody by western blot analysis. Northern blot analysis showed that the iNOS mRNA was approximately 4.5 kb, using a cDNA fragment for human iNOS, isolated from stimulated A-172 cells by reverse transcriptase-PCR, as a probe. The mRNA was induced by interferon-gamma at a trace level, and its expression was synergistically enhanced by simultaneous addition of lipopolysaccharide, tumor necrosis factor-alpha, and, to a larger extent, interleukin-1 beta. The mRNA expression was blocked by coincubation with actinomycin D or cycloheximide. Furthermore, by transfecting the mouse iNOS gene promoter into A-172 cells, transcriptional activation of the iNOS gene was detected in these cells upon stimulation with lipopolysaccharide and cytokines. The pattern of promoter activation correlated well with that of iNOS mRNA expression upon stimulation. These data indicate that expression of iNOS is transcriptionally regulated in A-172 cells. This process requires de novo protein synthesis with a mechanism similar to that in place in mouse macrophages.

Effects of head elevation on intracranial hemodynamics in patients with ventriculoperitoneal shunts

The present study was performed to investigate the effects of head elevation on intracranial hemodynamics in patients with ventriculoperitoneal (VP) shunts. The series included 35 hydrocephalic patients and five individuals without hydrocephalus who were used as controls. The hydrocephalic patients were divided into three groups: 15 patients who received VP shunts with a differential-pressure valve (DP group); 11 who received VP shunts with a variable-resistance valve (VR group), and 13 hydrocephalic patients (Hyd group) who had not received shunts (four underwent VP shunts later). The cerebral blood flow (CBF) of patients in the supine and upright positions was measured by technetium-99m hexamethylpropylenamine oxide (HMPAO) single-photon emission computerized tomography in each patient, using the subtraction technique. Cerebral perfusion pressure (CPP) was taken as the difference between the mean arterial blood pressure and ventricular fluid pressure, both referenced to the level of the foramen of Mono. The patients' heads were elevated stepwise from supine to upright. Percent changes of the mean CBF in the upright position (% delta mCBFupr) were 24.9% +/- 4.3% (mean +/- standard error of the mean) in the DP group, 6.2% +/- 2.7% in the VR group, 3.5% +/- 2.6% in the Hyd group, and 4.5% +/- 2.2% in the control group. Patients in the DP group showed a pathological increase in CPP with head elevation, whereas those in the Hyd and VR groups showed a physiological decrease in CPP. Three patients with differential-pressure valves, whose % delta mCBFupr was markedly high, developed low-intracranial pressure syndrome. In conclusion, shunted patients with a DP valve showed pathological intracranial hemodynamics in the upright position. This pathological hemodynamic stress in patients with long-standing differential-pressure valve implantation may induce pathological changes in the brain such as subependymal gliosis.

Endothelin-1 is involved in the transient hypoparathyroidism seen in patients undergoing thyroid surgery

We have studied the serial changes in plasma endothelin (ET)-1, serum parathyroid hormone (PTH) and serum calcium concentrations during surgery in 20 patients undergoing a hemithyroidectomy for thyroid carcinoma. The plasma ET-1 concentrations increased within the first 24 h following surgery in 18 out of 20 cases with the peak concentration achieved between 1 and 12 h. Gel permeation chromatography showed only one major peak at the elution position of human ET-1 standard both in the pre- and postoperative plasma. Thirteen patients showed transient hypoPTHaemia and hypocalcaemia which clearly coincided with the peak plasma ET-1 concentration in 12. However, there was no significant association between the extent of the increase in the plasma ET-1 levels and the incidence of the transient hypoparathyroidism. When blood was sampled at multiple sites during surgery, the plasma ET-1 concentrations tended to be higher in the internal jugular vein on the side of the preserved thyroid lobe (4.92 +/- 2.21 pg/ml) as well as on the side of the lobectomy (4.36 +/- 1.95) compared with that in the antecubital vein (3.66 +/- 1.44). Furthermore, tissue extracts from the parathyroid and thyroid contained considerably greater amounts of immunoreactive (ir-) ET-1 than most of the other tissues tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Soy protein has no hypocholesterolemic action in mice because it does not stimulate fecal steroid excretion in that species

We compared the effects of dietary soy protein isolate (SPI) and casein on plasma cholesterol level and fecal steroid excretion in rats, mice and hamsters. In rats, compared with casein, SPI significantly stimulated fecal steroid excretion in 9 out of 12 experiments with or without dietary cholesterol, whereas it suppressed plasma cholesterol level in 5 experiments and tended to suppress that, though not significantly, in 4 experiments. In mice, on the contrary, no significant difference was observed between the effects of casein and SPI on either the fecal steroid excretion or plasma cholesterol level in most of 12 experiments in which three different strains were tested. High-molecular-weight fraction of undigested residue of SPI exhibited marked hypocholesterolemic and steroid excretion-stimulating effects in rats and hamsters, whereas it showed only mild effects in mice. The species-dependent difference indicated the existence of inverse correlation between fecal steroid excretion and plasma cholesterol level and supported the view that in species like rat and hamster, but not mice, SPI lowers plasma cholesterol level by stimulating fecal steroid excretion.

Intraoperative radiation therapy for brain tumors with emphasis on retreatment for recurrence following full-dose external beam irradiation

We performed intraoperative radiotherapy (IORT) in 19 patients with various brain tumors. IORT was given for primary tumors in 2 patients with malignant glioma, but was used for treating recurrent tumors in the other 17 patients. The former 2 patients respectively received 33 Gy by IORT alone and 30 Gy by IORT in combination with 50 Gy of external beam radiotherapy (EBRT), and survived for 12 and 9 months. The latter 17 patients had received EBRT at 4 to 112 months before IORT. In this group, single doses of 23-40 Gy were delivered by IORT after removing as much tumor as possible. The median survival time after IORT was 12 months for 9 patients with glioblastoma or anaplastic astrocytoma, while it was 51 months for 8 patients with less infiltrative tumors (ependymoma, anaplastic ependymoma, and anaplastic oligodendroglioma). One patient with ependymoma and another with anaplastic ependymoma are currently alive with no evidence of disease at 7 and 11 years after IORT, respectively. Symptomatic brain necrosis occurred in 3 patients following IORT, but the symptoms were relieved in 2 of them by the removal of necrotic brain tissue. It is concluded that IORT combined with extensive tumor removal has an acceptable toxicity in previously irradiated patients and can be effective for selected recurrent malignant brain tumors.

Elevation of serum group II phospholipase A2 levels in patients with advanced cancer

To investigate the role of group II phospholipase A2 (M-PLA2) in cancer, we examined M-PLA2 serum levels in 170 pre-operative patients with various cancers and found elevated levels in 49% of them. M-PLA2 serum levels were significantly higher in patients with tumor stages T2-4, N1, M1 and stages II to IV than in T1, N0, M0 and stage I tumors, respectively. In all nine post-operative patients tested, M-PLA2 decreased 14 days after tumor resection and reduced to normal levels in 4 patients. Six of 16 carcinoma cell lines (37.5%) spontaneously secreted M-PLA2 into the culture supernatant despite the absence of IL-6 and IL-1 in 5 of the 6 lines. These results demonstrate that M-PLA2 produced by cancer cells may contribute, at least in part, to the elevation of serum M-PLA2 levels observed in cancer patients.

Immunoelectron microscopic localization of E-cadherin in dorsal root ganglia, dorsal root and dorsal horn of postnatal mice

Sensory neurons and associated glial cells are known to express the cell-cell adhesion molecule E-cadherin. The cellular and subcellular localization of this molecule in the dorsal root ganglion, dorsal root, and spinal cord of postnatal mice was studied by the pre-embedding immunoelectron microscopic labelling technique. In the dorsal root and the superficial layer of the dorsal horn, a subset of fasciculating unmyelinated axons expressed E-cadherin at their axon-axon contacts at all ages studied, and these axons were clustered together and segregated from E-cadherin-negative axons. In contrast, pre-myelinating large-diameter axons in P2 mice as well as myelinated axons in mice from P14 to adulthood were E-cadherin-negative. Glial cells also expressed E-cadherin: In the dorsal root ganglia, all of the satellite cells expressed E-cadherin at contact sites with neurons, other satellite cells, and basal lamina, at all ages studied. In dorsal roots from P14 to adulthood, myelin-forming Schwann cells expressed E-cadherin at the outer mesaxons and the contact sites with basal lamina. Non-myelin-forming Schwann cells occasionally stained for this molecule at contact sites with the plasma membrane of E-cadherin-positive axons and at other sites. These results strongly suggest that E-cadherin plays an important role in the selective fasciculation of a particular subset of unmyelinated sensory fibres, and also in glial cell contacts.

Reversibility of transient focal cerebral ischemia evaluated by somatosensory evoked potentials in cats

We designed this study to determine whether somatosensory evoked potentials (SEP) could be a reliable indicator to detect development of cerebral infarction or to predict reversibility of cerebral ischemia by investigating relationship among SEP, local cerebral blood flow (l-CBF), and histological changes after transient occlusion of the middle cerebral artery (MCA) in 36 cats. In 24 cats (group 1), gradual recovery of the cortical SEP was observed despite continued MCA occlusion, whereas the SEP remained lost in the remaining 12 cats (group 2). In group 1, amplitude of cortical SEP recovered completely 6 hours after recirculation following 30, 60, or 120 minutes of MCA occlusion, and only one developed cortical infarction. In six cats of group 2, the circulation was restored after 30 minutes of MCA occlusion. All showed complete recovery of SEP amplitude and none developed cortical infarction. When the MCA occlusion lasted 60 minutes in the remaining six cats, there was no recovery of the SEP amplitude and large cortical infarction was found in all six cats. Our findings suggest that SEP is a useful monitor for detecting cerebral infarction after MCA occlusion and that the critical time to avoid cerebral infarction would be 30 minutes when cortical SEP remains lost.

Effects of clenbuterol, a beta 2-adrenoceptor agonist, on macronutrient selection in rats

In these studies, clenbuterol, a beta 2-adrenergic agonist, was injected into male rats and the intake of a three-choice macronutrient diet was measured. The intakes of fat and protein were selectively inhibited by clenbuterol in both overnight-fasted and freely fed rats. There was no effect of clenbuterol on carbohydrate intake. Prior administration of nadolol, a beta-adrenergic antagonist, which does not easily pass the blood-brain barrier, completely antagonized the anorectic effect of clenbuterol. However, section of the hepatic branch of the vagus nerve did not abolish the nadolol effect. These results suggest that the anorectic effect of clenbuterol is mediated by peripheral beta 2-adrenergic receptors rather than central beta 2-adrenoceptors, and is not related to information transmitted from the liver via the vagus nerve.

The role of cerebrospinal fluid cytology in radiotherapy planning for intracranial germinoma

PURPOSE

The association between the cerebrospinal fluid cytology findings and the clinical features of patients with intracranial germinoma was investigated to determine whether cerebrospinal fluid cytology could be helpful in determining the optimal radiation treatment volume.

METHODS AND MATERIALS

Between 1976 and 1992, cerebrospinal fluid cytology was performed in 42 germinoma patients using a cytocentrifugation method. Forty patients received irradiation and 2 received chemotherapy with cisplatin and etoposide.

RESULTS

Cerebrospinal fluid cytology was positive in 22 of the 42 patients (52%). Dissemination via cerebrospinal fluid (intraventricular or spinal) was present at the initial diagnosis in eight (36%) of the 22 cytology-positive patients and none of the 20 negative patients. After treatment, cerebrospinal fluid dissemination developed in four (18%) of the cytology-positive patients and one (5%) of the negative patients. Two of the former four patients had received chemotherapy alone as initial treatment. Five patients with positive cytology received irradiation to a smaller volume than the cerebrospinal axis (primary tumor site plus spinal axis in three and whole brain in two), but they have not developed recurrence in the 4 to 14 years since therapy. The 5-year survival rate was 93% for the cytology-positive patients and 94% for the negative patients.

CONCLUSION

Cerebrospinal fluid cytology-positive patients have a higher risk of cerebrospinal fluid dissemination and it seems reasonable to give them low-dose (20-24 Gy) prophylactic craniospinal irradiation. When properly irradiated, the prognosis of cytology-positive patients is as good as that of negative patients.

Expression of two types of nitric oxide synthase mRNA in human neuroblastoma cell lines

Expression of nitric oxide synthase (NOS) was studied in nine human neuroblastoma and two human glioblastoma cell lines. Neuronal NOS (n-NOS) mRNA of approximately 10 kb was detected in four of the nine neuroblastoma cell lines by northern blot analysis using human n-NOS cDNA as a probe. Expression of the n-NOS mRNA was also detected in another neuroblastoma cell line in a subsequent reverse transcriptase polymerase chain reaction (RT-PCR) study, but no n-NOS mRNA expression was observed in the other four neuroblastoma cell lines or in the glioblastoma cell lines. The level of NOS activity correlated well with that of n-NOS mRNA expression in neuroblastoma cell lines expressing n-NOS mRNA. Western blot analysis showed that the n-NOS expressed in neuroblastoma cells was a 160-kDa protein reacted with anti-n-NOS antibody. By using the RT-PCR method, a short n-NOS (n-NOS-2) mRNA with a 315-bp inframe deletion from the entire n-NOS (n-NOS-1) mRNA was detected in the human neuroblastoma cells. The structural diversity of human n-NOS mRNA was demonstrated for the first time.

Relationship between food intake and metabolic rate in rats treated with beta-adrenoceptor agonists

The purpose of the present experiment was to clarify the interaction between food intake and activity of the thermogenic component of the sympathetic nervous system by studying the dose response relationships of typical beta 1-, beta 2-, and beta 3-adrenoceptor agonists on oxygen consumption and food intake. The data showed that the ED50 for the effects of Dobutamine (beta 1), Clenbuterol (beta 2) and ICI D7114 (beta 3) agonists on food intake were 8.9, 0.041 and > 1.1 mumol/kg respectively whereas the ED50 values for stimulation of metabolic rate were 7.1, 1.3 and 0.11 mumole/kg respectively. The marked differences in ED50 values for suppression of food intake and stimulation of metabolic rate for both clenbuterol and ICI D7114 suggest that the regulation of feeding and of metabolic rate in response to these agonists are independent of each other. The experiments also identified that Clenbuterol activated a very sensitive beta 2-adrenergic system for the regulation of feeding behavior.

Overexpression of group II phospholipase A2 in human breast cancer tissues is closely associated with their malignant potency

Membrane-associated phospholipase A2 (M-PLA2) is an enzyme that hydrolyses the sn-2 fatty acyl ester bond of phosphoglycerides. We measured M-PLA2 concentration in tissue extracts from 325 human breast cancers using a specific radioimmunoassay recently developed. Correlation analyses between the tissue concentration of M-PLA2 and clinicopathological factors showed that the enzyme level was significantly higher in patients with distant metastasis than in those without. In addition, M-PLA2 concentration was significantly higher in scirrhous carcinoma than in other histological types. No significant association was found between M-PLA2 concentration and age, menstrual status, tumour size, histological grade, vessel involvement or oestrogen receptor (ER) and progesterone receptor (PR) status. The expression of M-PLA2 mRNA was examined in a fibroadenoma, a stage IV breast cancer and its metastatic site of skin. Northern blot analysis showed a clear hybridisation band corresponding to M-PLA2 mRNA in both primary breast cancer and its metastatic site, while the fibroadenoma expressed a faint band corresponding to M-PLA2 mRNA. Breast cancer patients with high M-PLA2 concentrations exhibited significantly shorter disease-free and overall survival than those with low M-PLA2 concentration at the cut-off point of 5 ng 100 mg-1 protein, which was determined in a separate study. In multivariate analysis, M-PLA2 was found to be an independent prognostic factor for disease recurrence and death in human breast cancer. The possible significance of M-PLA2 expression in human breast cancer tissue is discussed.

Immunoreactive hepatocyte growth factor is a strong and independent predictor of recurrence and survival in human breast cancer

Hepatocyte growth factor (HGF) is a stromally derived modulator of epithelial cell proliferation and motility. In the present study, we have measured immunoreactive (ir)-HGF concentration in tumor extracts of 258 primary human breast cancers using an enzyme-linked immunosorbent assay and have evaluated its association with disease-free and overall survival. The median value of ir-HGF concentration was 11.0 ng/100 mg protein (range, 1.4-566.7 ng/100 mg protein). Correlation analyses between ir-HGF concentration and clinicopathological factors showed that the ir-HGF level was correlated only with tumor size (P = 0.05). No significant associations were found between ir-HGF content and age, menopausal status, nodal status, histological type, histological grade, vessel involvement, estrogen receptor, progesterone receptor, type of surgery, or postoperative adjuvant therapy. Breast cancer patients with high ir-HGF concentration had a significantly shorter relapse-free (P = 0.001) and overall survival (P = 0.001) rate when compared to those with low ir-HGF concentration at the cutoff point of 21.7 ng/100 mg protein, which was determined in another group of 82 patients. In multivariate analysis, ir-HGF level was found to be the most important independent factor in predicting relapse-free and overall survival, of greater import than lymph node involvement. The putative role of HGF in breast cancer growth and metastasis is hereby strengthened.

Group II phospholipase A2 in invasive gastric cancer cell line is induced by interleukin 6

To investigate the role of group II phospholipase A2(PLA2) in cancer, we examined the expression and secretion of group II PLA2 in response to the stimulation of interleukin 6(IL-6) in human gastric cancer cells in vitro. Group II PLA2 determined by a specific radioimmunoassay was constitutively produced in culture supernatant of KATO III (signet ring cell carcinoma) and MKN28 (well differentiated adenocarcinoma). This production in KATO III significantly increased with a treatment of IL-6, whereas that in MKN28 remained at a same level. Moreover, the quantitation by reverse transcription-polymerase chain reaction(RT-PCR) demonstrated the IL-6 inducible overexpression of group II PLA2 mRNA in KATO III. This transcription was mediated by NF-IL6, the same as in hepatocytes. These results suggest two possible mechanisms of group II PLA2 production by cancer cells in vivo, that is, cytokine-induced production and constitutive production.