Hepatocyte growth factor stimulates wound repair of the rabbit esophageal epithelial cells in primary culture

We have recently established an in vitro primary culture system for esophageal epithelial cells, which enabled us to investigate the effect of hepatocyte growth factor (HGF) and other factors on esophageal restitution. HGF remarkably stimulated restitution of these cells. So did epidermal growth factor (EGF), though moderately. Restitution velocity of esophageal cells was remarkably higher than that of gastric epithelial cells. The expression of c-met, specific HGF receptor was demonstrated by the esophageal cells, suggesting that the effect of HGF was mediated by its specific receptor. The expression level of c-met mRNA was the same as that of gastric epithelial cells, as assessed by competitive RT-PCR technique. These results suggest that HGF might be involved in the repair process of esophageal mucosal damage.

Atrophic nerve fibers in regions of reduced MIBG uptake in doxorubicin cardiomyopathy

A myocardial MIBG-SPECT examination was conducted 2 wk after doxorubicin chemotherapy on a 52-yr-old woman without cardiac symptoms. Despite normal 201TI scintigraphy, reduced MIBG uptake was detected in the apical anterior, inferior and lateral segments of the left ventricle. The patient died of congestive heart failure due to doxorubicin-induced cardiomyopathy 10 mo later. At necropsy, the left ventricle was markedly dilated and the apical anterior, inferior and lateral walls were thin, stiff and whitish. Nerve fibers in the apical inferior wall were atrophic and markedly fibrotic where MIBG uptake was most reduced. Nerve fibers in the septum were normal where MIBG uptake had remained normal. The histologic findings correspond with the findings on the MIBG image. MIBG imaging may detect cardiac sympathetic denervation in doxorubicin-induced cardiomyopathy before cardiac symptoms are manifest and cardiac function deteriorates.

Long-term results of operation for carcinoma of the stomach in T1/T2 stages: critical evaluation of the concept of early carcinoma of the stomach

BACKGROUND

The significance of nodal metastasis in patients with early gastric cancer (ECG) (T1) is unknown. It has been suggested that patients with T2, N0 carcinoma of the stomach have a comparable survival rate to patients with T1 carcinoma of the stomach.

STUDY DESIGN

A retrospective review and survival analysis of 321 patients with T1/T2 adenocarcinoma of the stomach treated between 1979 to 1991 were performed.

RESULTS

Patients were divided into four groups: group 1, 214 patients with node-negative EGC (T1, N0); group 2, 13 patients with node-positive EGC (T1, N+); group 3, 49 patients with node-negative T2 disease (T2, N0); and group 4, 45 patients with node-positive T2 disease (T2, N+). Excluding deaths from causes other than recurrence, the survival rate for patients in groups 1 and 3 was 100 percent, in contrast to the ten-year survival rate of 72.7 percent for group 2 and 62.5 percent for group 4 patients (p < 0.001, groups 1 versus 2, groups 3 versus 4). The ten-year survival rate for patients with node-negative T2 disease (group 3, 100 percent) was significantly better than that of patients with node-positive EGC (group 2, 72.7 percent) (p < 0.001). Although differences in the survival rates were noted according to lymphatic or venous invasion and whether or not patients had EGC or T2 carcinoma, the most significant factor was lymph node invasion.

CONCLUSIONS

The postoperative survival rate for patients with node-positive EGC was poorer than that for those with node-negative T2 carcinomas. Reevaluation of the concept of EGC may be necessary. Post-operative chemotherapy does not appear necessary in patients with T2, N0 disease.

Validation of noninvasive quantification of rCBF compared with dynamic/integral method by using positron emission tomography and oxygen-15 labeled water

This study proposes a new solution for the quantification of rCBF pixel-by-pixel using PET and 15O-H2O. The method represents an application of weighted integration that used PET image only, requiring no input function of arterial blood. It generates the rCBF image quickly and automatically. Simulation studies revealed that the calculation of rCBF was fairly stable as long as a relatively shorter scan frame time and longer scan time were selected. Calculated images of actual PET study by this method correlated significantly with those identified by the dynamic/integral method. Because this procedure could detect whole brain CBF change between different studies as accurately as by the dynamic/integral method, this procedure may be the most suitable for brain activation studies.

Change in hepatic handling of hepatocyte growth factor during liver regeneration in rats

The change in the hepatic uptake clearance of hepatocyte growth factor (HGF) during liver regeneration in rats was examined. The hepatic uptake clearance per gram liver of 125I-labeled HGF in vivo decreased to a minimum level only 15 min after partial hepatectomy (PH). In the perfused liver, in which the effect of endogenous substances can be ignored, the hepatic uptake clearance of 125I-HGF did not change until at least 3 h after PH, suggesting that the decrease in the clearance in vivo is caused by some endogenous inhibitors. Such a decrease in the clearance cannot be explained only by the elevated endogenous HGF concentration in plasma. In addition, at 48 h after PH the decrease in hepatic uptake clearance was comparable for in vivo and perfused liver (approximately 50 and 60% reduction, respectively), suggesting that the decreased hepatic clearance in vivo at that time was caused mainly by reduction in the binding and/or uptake by the liver itself. In addition, the hepatic uptake clearance of 125I-HGF at that time in the presence of an excess (135 pM) of unlabeled HGF was comparable with that of the control, indicating that only the saturable portion of hepatic uptake clearance is reduced. The internalization rate constant representing the probability of cell surface-bound 125I-HGF being internalized per unit time increased to three times that of the control at 15 min after PH, demonstrating that the internalization of HGF is enhanced immediately after the start of liver regeneration.

Effect of tauroursodeoxycholic acid on bile flow and calcium excretion in ischemia-reperfusion injury of rat livers

BACKGROUND/AIMS

Tauroursodeoxycholic acid is known to have a hepatoprotective action in cholestatic disorders. We evaluated whether oral pretreatment with tauroursodeoxycholic acid could protect the liver from ischemia-reperfusion injury, with particular regard to its effect on bile flow and biliary calcium excretion.

METHODS

A 1-hour in vivo ischemia-reperfusion model of 70% of the lobes of rat liver was used. Animals were divided into six groups (each group; n = 8); a non-ischemia sham group (CS), a control group without bile acids (CON), and 4 bile acid groups; 10 mg/kg and 50 mg/kg (U10, U50), taurocholic acid 10 mg/kg (CA10) and tauroursodeoxycholic acid 10 mg/kg (CD10). Bile acids were given orally for 7 days before operation.

RESULTS

Three hours after reperfusion, oral bile acid pretreatment failed to reduce the hepatic ischemia-reperfusion injury biochemically, but histological improvement was observed in the tauroursodeoxycholic acid groups. After reperfusion, tauroursodeoxycholic acid significantly increased bile flow from the ischemic liver, and also significantly increased serum calcium concentration. Although tauroursodeoxycholic acid did not change biliary calcium concentration, it significantly enhanced total biliary calcium output during reperfusion.

CONCLUSION

Thus, tauroursodeoxycholic acid inhibited tissue calcium accumulation and enhanced sinusoidal and biliary calcium output during hepatic ischemia-reperfusion. However, it is still unclear if calcium mobilization is part of the protective mechanisms of tauroursodeoxycholic acid in ischemia-reperfusion injury of the liver.

Myxoid and globular degeneration of nerves in the shoulder joint

Characteristic degeneration of the nerves in shoulder joints was recognized in 26 of 35 capsules (74.3%) from 20 cadavers. No left or right or gender differences were found. Histologic features of the nerves were (1) thickening of the perineurium, (2) myxoid degeneration in the endoneurium, and (3) hyaline globular structures with a whorled, oligocellular appearance regarded as Renaut bodies. The results of histochemical and electron microscopic studies showed prominent degenerated collagen fibers in the globular areas. These features resembled those found in the fusiform swelling in the axillary nerve branch to the teres minor muscle, believed to be caused by chronic nerve compression. Sixty percent of the degenerated nerves occurred in the anteroinferior and posteroinferior portions of the capsule, an area that is considered to be innervated by the axillary nerve. No correlation between age and severity of these degenerative nerve changes was noted. Compression of the axillary nerve and inferior joint capsule caused by repetitive shoulder movement such as forward flexion, abduction, and external rotation of the humerus might result in this form of nerve degeneration found histologically over a lifetime without necessarily causing clinical symptoms.

[Automatic determination for bone morphometry using a computed image analyzer]

An image analyzer which combines a digitizer and a computer is widely employed in bone histomorphometrical evaluation. With this method, however, all regions of determination are traced manually so that considerable time is consumed when many preparations are measured. To resolve this problem, we have developed an automatic program for rapid and quantitative measurement of many bone histomorphometrical parameters using a computed color image analyzer. The bone volume (BV), tissue volume (TV), osteoid surface (OS), and the bone surface (BS) of rat tibia metaphysis were measured by this automatic method, and by the manual method using an image analyzer. The correlation coefficient between both methods in measuring BV/TV was 0.98 and in measuring OS/BS was 0.96. The reproducibility and accuracy of both methods for these parameters were similar. The time required for the automatic method was much shorter than that for the manual method. Various parameters of the tibial metaphysis, lumbar vertebral body, and femoral mid-diaphysis in ovariectomized rat (Fischer) measured by this method were in good agreement with values reported previously.

Clinicopathologic study of primary gastric lymphoma of B cell phenotype with special reference to low-grade B cell lymphoma of mucosa-associated lymphoid tissue among the Japanese

Resection specimens from 83 patients with primary gastric lymphoma (PGL) of B cell phenotype at stage IE and at stage IIE according to the Ann Arbor classification were investigated. Histologically, these lymphomas could be divided into four types: Type I lesions (n = 24) were entirely made up of MALT lymphoma; Type II lesions (n = 13) were predominantly MALT lymphoma containing one to a few foci of high-grade B cell lymphoma; Type III lesions (n = 22) consisted largely of high-grade lymphoma with small areas of low-grade MALT lymphoma; and Type IV lesions (n = 24) were pure high-grade B cell lymphoma, mostly of the large cell type. All patients had undergone primary gastric resection, and 14 received additional chemotherapy (n = 12), or both chemotherapy and radiotherapy (n = 2). The survival probability was significantly higher for Types I and II lymphomas than for Types III and IV tumors (P < 0.05 by the generalized Wilcoxon test). According to The General Rules for the Gastric Cancer Study by the Japanese Research Society for Gastric Cancer, the stage of disease showed a clear distinction between each of them (P < 0.01 by the generalized Wilcoxon test). This staging method seemed to serve well as a prognostic indicator. The histological typing of the PGL of the present series also seemed to correlate with the gross appearance, pathologic stage and prognosis. Furthermore, the expression of cyclin D1, bcl-2 and p53 protein, and PCNA was immunohistochemically investigated in 42 cases of the present series. Most of the low-grade PGL (Types I and II) had less than 60% PCNA-positive cells, whereas the high-grade PGL (Types III and IV) had more than 60% positive cells. In a study for cyclin D1 protein, no cases showed the nuclear staining pattern characteristic for mantle cell lymphoma, and the cytoplasmic staining frequently observed in the node-based large B cell lymphoma was seldom identified in the PGL. This discrepancy might suggest a lineage difference among the morphologically similar, but site-different, lymphomas. On the other hand, bcl-2 protein overexpression was almost equal in frequency between the gastric and node-based high-grade B cell lymphomas. This is in contrast to the reports from Western countries, in which the majority of high-grade gastric tumors were bcl-2 negative.

[Alterations of cardiac function and metabolism in the rat heart-lung preparation by methyl methacrylate (MMA) and their protection by ulinastatin]

We have assessed the deleterious effects of methyl methacrylate (MMA) on cardiac function and metabolism in the isolated heart-lung preparation and their protection by ulinastatin. Twenty-four male Wistar rats were prepared for the heart-lung model. They were randomly divided into 3 groups. In the MMA (M) and ulinastatin (U) groups, MMA 1000 micrograms.ml-1 was administered 7 minutes after the start of perfusion. At the end of the experimental period, the hearts were freeze-clamped and then myocardial high energy phosphates, lactate and glycogen were measured. Cardiac output decreased significantly in the M and U groups. Po2 of the perfusion blood in the M and U groups was significantly lower than that in the control (C) group. Myocardial ATP in the M and U groups was significantly lower than that in the C group. ADP and AMP in the M and U groups were higher than those in the C group. Although there was no significant difference in lactate levels among the 3 groups, glycogen in the U and C groups was significantly higher than that in the M group. MMA 1000 micrograms.ml-1 is much higher than the blood level (0.05-31.89 micrograms.ml-1) reported clinically in patients who had femoral prosthesis. Ulinastatin increased myocardial glycogen content which had been reduced by MMA. This may suggest that ulinastatin has a protective effect on heart damaged by MMA.

[Effect of cilazapril on exercise tolerance and neurohumoral factors in patients with asymptomatic chronic heart failure after myocardial infarction]

The effects of cilazapril on exercise tolerance and neurohumoral factors were investigated in old myocardial infarction (OMI) patients with asymptomatic heart failure and reduced left ventricular ejection fraction. Cilazapril (0.5 mg) was administered once daily to OMI patients (n = 20) [NYHA class I, sinus rhythm, ejection fraction by radionuclide scanning < 50% (36.8 +/- 9.1%, mean +/- SD)]. Two weeks later, five patients were excluded from the study because of cough or hypotension, and 15 patients received 1.0 mg cilazapril once daily for the next 6 weeks. Exercise tolerance, neurohumoral factors and ejection fraction were measured in OMI patients before and after administration of cilazapril. Seven age-matched healthy adults served as the controls. OMI patients had latent heart failure because their exercise tolerance values and aldosterone levels were lower and alpha-atrial natriuretic polypeptide levels were higher than those in healthy subjects. In OMI patients, 8 weeks after cilazapril administration, exercise duration increased from 545 +/- 59 to 590 +/- 74 sec (p < 0.05), anaerobic threshold from 17.5 +/- 3.2 to 20.1 +/- 2.8 ml/min/kg (p < 0.05), peak-VO2 from 23.5 +/- 4.7 to 27.1 +/- 4.4 ml/min/kg (p < 0.05), plasma renin activity from 1.34 +/- 1.13 to 5.82 +/- 5.47 ng/ml/hr (p < 0.01) and alpha-atrial natriuretic polypeptide decreased from 100.7 +/- 44.3 to 80.5 +/- 28.0 pg/ml (p < 0.05). In patients with asymptomatic left ventricular dysfunction after myocardial infarction, 8 week's cilazapril administration improved exercise tolerance and neurohumoral conditions.

Analysis of proliferative activity using antiproliferating cell nuclear antigen antibody in colorectal cancer

Using anti-PCNA antibody (PC10), an immunohistochemical study of the expression of PCNA in formalin-fixed and paraffin-embedded materials of colorectal cancer patients was performed and correlation of PCNA expression with clinicopathological findings and DNA ploidy pattern was studied. PCNA labeling rate (PCNA LR) was estimated in the advancing margin of the tumor and ranged from 23.8% to 77.9%. There was a significant difference in lymphatic vessel invasion, liver metastasis and Dukes' stage between the groups with high (> 48.7) and low (< 48.7) PCNA LR (P < 0.05). No differences were seen in tumor size, histological type, lymph node metastasis or DNA ploidy pattern. In patients with younger age, infiltration to neighboring organs, a high degree of venous invasion, and peritoneal dissemination, the frequency of high PCNA LR tended to be higher (P < 0.1). The results above suggest that a high proliferative activity as defined by evaluation of the PCNA LR at the advancing margin of the tumor may be one of the parameters of malignant potential and helpful as a predictor of liver metastasis in colorectal cancer.

Release of superoxide radicals by mouse macrophages stimulated by oxidative modification of glycated low density lipoproteins

Diabetic patients have high levels of glycated LDL. Although glycated LDLs are implicated in the development of atherosclerosis in such patients, convincing data are lacking. We observed release of superoxide radicals (O2-) from mouse resident peritoneal macrophages stimulated by an oxidized/glycated LDL by using a highly sensitive and specific chemiluminescence method. Oxidized/glycated LDL was achieved by an addition of low concentration of Fe3+ to glycated LDL. Macrophages took up an appreciable amount of the glycated LDL oxidized by iron, leading to the development of foam cells, while they did not take up untreated glycated LDL or the native LDL. These observations clearly indicate that the oxidized/glycated LDL reacts well with macrophages. Since an oxidation of glycated LDL may occur in vivo, the oxidized/glycated LDL might play an important role in atherogenesis.

Evaluation of the effects of various factors on the serum alpha hydroxybutyrate dehydrogenase activity in young females

In this study, for determining the influence of different life style on the serum alpha hydroxybutyrate dehydrogenase activity (alpha HBD), we carried out surveys and laboratory studies on the relationships of the nutritional intake, physical activity, cigarette smoking and alcohol consumption of young females with their serum alpha HBD activity. There are significant positive correlation between alpha HBD and GOT, GPT, LDH, CPK, phospholipids, total cholesterol, and HDL-cholesterol, and significant negative correlation between alpha HBD/LDH and GOT, GPT, and gamma GTP. There are significant positive or negative correlation between alpha HBD and systolic pressure, diastolic pressure, cardiac index, stoke volume and total periperal resistance, and significant negative correlation between alpha HBD/LDH and vital capacity in young females. The serum alpha HBD activity levels of nonsmokers was significant higher than those of smokers (p < 0.05). There are significant positive correlations between serum alpha HBD activity and beverage consumption, and between alpha HBD/LDH and protein, calcium, vitamin A, B1, B2, C, pulses, vegetables and milk in young females. The finding shows that the group of serum alpha HBD activity level of 240 or more units exhibited higher level of rate of those who exercised sometimes+usually than the other group in young females. However, the serum alpha HBD activity level did not show significant correlation with energy expenditures per day. Exercise at 50 and 70% VO2 max may produce a significant increase in their serum alpha HBD activity. There is a possibility that serum alpha HBD activity may serve as an indicator for ones health condition. It is undeniable that observation of variation of serum alpha HBD activity is highly significant in health maintenance.

[Bone mineral density in postmenopausal elderly women with type 2 diabetes]

We measured lumbar bone mineral density (L2-4 MBMD) in the postmenopausal elderly diabetic women and made comparisons with age-matched controls in terms of the age, body mass index (BMI) and % BMD of age-matched. In addition we evaluated the correlation between BMD and menarche age, menopause age, HbA1c, serum calcium, serum phosphate, serum alkaline phosphatase (S-Alp) and the ratio of urine calcium to urine creatinine (UCa/Cr). Moreover we divided non-insulin dependent diabetic patients (NIDDM) into two groups; the high BMD group and the low BMD group. Serum Alp and the ratio of UCa/Cr were compared in these two groups. The relationships between regimen of therapy and BMD were also analyzed in female NIDDM. There were no significant differences of BMD and background factors between controls and NIDDM. The ratio of UCa/Cr in the high BMD group were significantly less than that in low BMD group (p < 0.05). BMD in NIDDM with retinopathy was lower, but not significantly, than that in NIDDM without retinopathy. The methods of therapy for NIDDM such as diet alone, an oral hypoglycemic agent and insulin did not influence BMD in elderly postmenopausal diabetics. These results indicated that BMD in elderly postmenopausal diabetics are dependent on UCa/Cr and retinopathy.

Contribution of parenchymal and non-parenchymal liver cells to the clearance of hepatocyte growth factor from the circulation in rats

PURPOSE

The distribution of 125I-hepatocyte growth factor (HGF) to either liver parenchymal cells (PC) or non-parenchymal cells (NPC) was investigated in rats.

METHODS

After injection of a trace amount of 125I-HGF, the distribution of radioactivity determined by microautoradiography closely resembled that of 125I-epidermal growth factor which distributes mainly to PC.

RESULTS

The uptake clearance of 125I-HGF estimated by determining the radioactivity of isolated liver cells was three times higher for PC than for NPC. This suggests that HGF distributes mainly to PC at relatively low doses. On the other hand, the uptake clearance by PC fell on coadministering an excess (80 micrograms/kg) of unlabeled HGF, while no change was observed for NPC, indicating that a saturable process for the hepatic handling of HGF exists only in PC where the HGF receptor is expressed.

CONCLUSIONS

At such a dose the uptake clearance was comparable for both PC and NPC showing that HGF distributes to both cell types although NPC have few HGF receptors. Since the distribution to NPC was relatively non-specific and heparin-sensitive, it may be that heparin-like substances, which are believed to exist on PC and/or the extracellular matrix, also exist on NPC.

Tissue-specific and light-responsive regulation of the promoter region of the Arabidopsis thaliana chloroplast omega-3 fatty acid desaturase gene (FAD7)

The Arabidopsis FAD7 gene encodes a chloroplast omega-3 fatty acid desaturase that catalyzes the desaturation of lipid-linked dienoic fatty acids (18:2 and 16:2). An 825 bp FAD7 promoter fragment upstream from the transcriptional start point contained several short sequences which were homologous to the cis-elements (box II, G-box, etc.) conserved in many light-responsive genes. We introduced the FAD7 promoter fused to the beta-glucuronidase (GUS) or the luciferase (LUC) reporter gene into tobacco plants. The -825 promoter sequence conferred tissue-specific and light-responsive expression to both these reporter genes in transgenic tobacco, indicating that these expressions of the FAD7 gene were regulated mainly at the transcriptional level. Histochemical GUS staining showed that the activity of the FAD7 promoter is restricted to the tissues with chloroplast-containing cells although the staining was noticeably absent in the chloroplast-containing cells associated with vascular systems. The 5' deletion experiments of the promoter revealed that the -362/-166 region, containing two putative box II sequences, was responsible for the tissue-specific and light-responsive expression of the FAD7 gene.

Antibodies to recombinant synaptotagmin and calcium channel subtypes in Lambert-Eaton myasthenic syndrome

Several proteins have been postulated as possible targets of immune attack in Lambert-Eaton myasthenic syndrome (LEMS). Heterogeneity of autoantibodies in sera from 20 LEMS patients was studied by comparing their reactivity to synaptotagmin, a synaptic vesicle protein, and voltage-gated calcium channels (VGCCs). Six patients' sera (1 with small cell lung carcinoma (SCLC)) contained antibodies specifically recognizing the recombinant synaptotagmin on immunoblots. Thirteen (11 with SCLC) and 16 (11 with SCLC and 1 with poorly differentiated cell carcinoma in the lung) patients' sera immunoprecipitated omega-conotoxin GVIA-labeled N-type and omega-conotoxin MVIIC-labeled Q-type VGCCs, respectively. Three of 6 synaptotagmin-positive sera had cross-reactivity with N and/or Q subtypes of VGCC; the remaining 3 showed no cross-reactivity with VGCCs. Results indicate that LEMS sera are heterogeneous in the spectrum of containing antibodies, and suggest that this heterogeneity reflects the immune response to various synaptic proteins including not only multiple VGCCs but also synaptosecretory complex proteins.

Mutagenicity studies with palm fruit carotene

The mutagenicity of palm fruit carotene was examined using the reverse mutation test with bacteria, the chromosomal aberration test with mammalian cells and the micronucleus test in mice. The carotene induced neither reverse mutation in Salmonella typhimurium TA98, TA1537, TA100, TA1535 and in Escherichia coli WP2uvrA, nor structural and numerical (polyploidy) chromosomal aberrations in the Chinese hamster fibroblast cell line (CHL). In addition, no increase in micronucleated polychromatic erythrocytes was elicited in the micronucleus test in CD-1(ICR) male mice. It is concluded that palm fruit carotene had no mutagenic activity in these in vitro and in vivo tests.

Normal age-related conversion of bone marrow in the mandible: MR imaging findings

OBJECTIVE

The mandible is one of the most common sites for osteomyelitis and other marrow-based diseases. Therefore, knowledge of the normal patterns of marrow distribution could help evaluate marrow-based diseases. The purpose of this study was to assess the age-related normal sequence of conversion from hematopoietic to fatty marrow in the mandible as depicted on MR images.

SUBJECTS AND METHODS

We prospectively reviewed T1-weighted MR images of the mandible for the distribution of hematopoietic and fatty marrow. Forty-five subjects 4 months to 25 years old with no known marrow abnormality were examined with the spin-echo technique. Marrow conversion was assessed in the condyle, ramus, angle, and body of the mandible using visual grading based on homogeneity, signal intensity, and a signal-intensity ratio determined by the intensities of the surrounding subcutaneous fat and air.

RESULTS

Conversion of hematopoietic to fatty marrow occurred first in the mandibular body, followed by the angle, ramus, and finally the condyle. The marrow in the region distal to the ramus had almost fully converted to fatty marrow by the third decade of life, but the remaining regions contained some hematopoietic marrow. Further substantiating these results, the signal-intensity ratio increased up to about 90% in the angle and 70% in the ramus by the age of 10 years and then leveled off. On the other hand, the signal-intensity ratio in the condyle reached 60% by age 15 and remained unchanged for the following 10 years.

CONCLUSION

The normal age-related conversion from hematopoietic to fatty marrow in the mandible follows a well-defined sequence, first seen in the mental region early in childhood, then in the body, the ramus, and finally the condyle.

[Treatment of refractory hypoxemia due to right-to-left interatrial shunt complicating right ventricular infarction: successful short-term percutaneous catheter closure of the patent foramen ovale]

Refractory hypoxemia as a complication of right ventricular infarction is rare. A 74-year-old man developed persistent hypoxemia due to right-to-left interatrial shunting through a patent foramen ovale during the acute phase of right ventricular infarction. Short-term percutaneous transvenous closure of the patent foramen ovale with a large balloon occlusion catheter was life-saving.

Osteoblasts are regulated by the cellular adhesion through ICAM-1 and VCAM-1

The two major processes of bone metabolism--bone formation and resorption--are regulated by cellular interactions. Osteoblasts and osteoclasts play a significant role in bone metabolism, which is known to be regulated by local soluble factors and systemic hormones. Although bone is a heterogeneous tissue comprised of osteogenic and hematopoietic cells, cellular adhesion of osteoblasts and its regulation remains to be understood. We first demonstrate that cellular adhesion by which osteoblasts communicate with opposing cells in bone milieu is involved in the osteoblast activation: (a) purified human osteoblasts obtained from osteoarthritis patients expressed particular adhesion molecules, ICAM-1, VCAM-1, and LFA-3; (b) toe osteoblasts adhered to T cells which were used as representative adhesive partners, since T cells possess all the receptors to these adhesion molecules; (c) mRNA transcription and secretion of IL-1beta and IL-6 were induced in the osteoblasts by the cellular adhesion to T cells and they were reduced by interrupting the adhesion; (d) cross-linking of ICAM-1 and VCAM-1 on the osteoblasts induced IL-6 secretion from the osteoblasts. These results indicate that osteoblasts adhere to opposing cells through particular adhesion molecules on their surface and that the adhesion molecules on the osteoblasts not only function as glue with opposing partners but transduce activation signals that facilitate the production of bone-resorbing cytokines. We propose that cellular adhesion of osteoblasts as well as soluble factors is significant for the regulation of bone metabolism.

p53 protein and proliferating cell nuclear antigen in eccrine poroma and porocarcinoma. an immunohistochemical study

The expression of p53 protein and proliferating cell nuclear antigen (PCNA) in 18 eccrine poromas and four porocarcinomas was examined by immunohistochemistry. Immunoreactivity for p53 in eccrine poromas was negative in five tumors, < 10% of tumor cells in one (low expresser), 10-50% in seven (moderate expressers), and > 50% in five (high expressers). The duration of the presence before excision of p53-negative poromas was shorter, and the size of these tumors was smaller in comparison with those of p53-positive poromas. Moreover, all high expressers showed some atypical cells in limited areas. Of the four porocarcinomas, three were high expressers and one a low expresser of p53 protein. The low-expresser tumor showed clinically more rapid growth and histologically no poromatous foci in contrast to the high expressers. No significant correlation was found between p53 protein expression and PCNA positive staining in either eccrine poromas or porocarcinomas. However, the percentages of PCNA-positive cells in porocarcinomas were significantly higher than those in poromas, with no overlapping values. These results suggest that the PCNA index is useful in differentiating between poroma and porocarcinoma and that p53 gene mutation may occur in long-standing eccrine poromas and correlate with atypical changes in histology as well as subsequent progression to porocarcinoma.

G10BP, an E1A-inducible negative regulator of Sp1, represses transcription of the rat fibronectin gene

Downregulation of the fibronectin (FN) gene in a rat 3Y1 derivative cell line, XhoC, transformed by the adenovirus E1A and E1B genes seems to be caused by the induction of a negative regulator, G10BP, which binds to three G-rich sequences in the promoter (T. Nakamura, T. Nakajima, S. Tsunoda, S. Nakada, K. Oda, H. Tsurui, and A. Wada, J. Virol. 66:6436-6450, 1992). These are the G10 stretch and two GC boxes consisting of the G10 stretch with one internal C residue insertion. The recognition sequences of G10BP and Sp1 (GGGCGG) overlap in these GC boxes. To analyze the mechanism of the downregulation, G10BP was purified by DNA affinity chromatography, and its molecular mass was estimated to be about 30 kDa. The promoter was modified by substituting the sequence GGGG with ATCC or CTTA in these G-rich sequences, leaving the Sp1 motif intact, and by replacing the Sp1 motif by the T stretch. Transcription of FN promoter-chloramphenicol acetyltransferase fusion genes carrying the base substitution in one or more of these G-rich sequences both in vivo and in vitro revealed that the base substitution in any G-rich sequence results in reduction of promoter activity, although the downstream GC box (GCd) plays a primary role. The addition of G10BP severely inhibited the activities of the FN promoters carrying the wild-type GCd in vitro, while the promoters carrying the mutant GCd were unaffected. The binding affinity of G10BP and Sp1 to each of the G-rich sequences, analyzed by gel shift assays, indicated that G10BP binds strongly to the GCd, moderately to the G10 stretch, and weakly to GCu, while Sp1 binds strongly to GCu, moderately to GCd, and weakly to the G10 stretch. Sp1 binding to GCd and the G10 stretch was inhibited by G10BP, while binding to GCu was unaffected. These results indicate that FN gene transcription is inhibited in XhoC cells primarily by exclusion of Sp1 binding to GCd by G10BP and that G10BP is a new class of Sp1 negative regulator.