Immunohistochemical study of p53, EGF, EGF-receptor, v-erb B and ras p21 in squamous cell carcinoma of hypopharynx

We have characterized 24 hypopharyngeal squamous cell carcinomas and 5 normal hypopharyngeal tissues by immunostaining with antibodies against epidermal growth factor (EGF), EGF-Receptor (EGFR), p53, v-erb B, and ras p21. The Avidin-Biotin Complex (ABC) technique was employed. Overexpression of p53 appeared in 17 of 24 cases of squamous cell carcinoma of the hypopharynx (normal mucosa: none, well differentiated: 60%, moderately differentiated: 71.4%, poorly differentiated: 71.4%). Some dysplastic mucosae surrounding cancer lesions showed overexpression of p53. EGF and EGFR tended to be expressed more strongly in carcinoma [EGF: 29.1% (well differentiated: 30%, moderately differentiated: 28.6%, poorly differentiated: 28.6%); EGFR: 50% (well differentiated: 60%, moderately differentiated: 42.9%, poorly differentiated: 42.9%)] than in normal mucosa (EGF: 0%, EGFR: 20%). The v-erb B stained positively in carcinoma [62.5% (well differentiated: 70%, moderately differentiated: 71.4%, poorly differentiated: 42.9%)] but negatively in normal mucosa. These data suggest that genetic mutations of p53 probably play an important role at an early stage of tumorigenesis, and that the networks of EGF, EGFR and v-erb B probably are involved in the development of hypopharyngeal squamous cell carcinoma.

Molecular cloning and chromosomal assignment of the mouse C-type natriuretic peptide (CNP) gene (Nppc): comparison with the human CNP gene (NPPC)

The mouse C-type natriuretic peptide (CNP) genomic fragment was isolated from a mouse genomic DNA library. The mouse CNP gene is composed of at least two exons and one intron. The 5'-flanking region contains an array of cis-acting regulatory elements and a dinucleotide CA repeat (microsatellite). Analysis of the deduced amino acid sequences revealed that mouse preproCNP is a 126-amino-acid peptide and that its C-terminal 22-residue peptide preceded by Lys-Lys is identical to porcine, rat, and human CNPs. On the basis of the polymerase chain reaction-analyzed microsatellite length polymorphisms among recombinant inbred strains of mice, the CNP gene (Nppc) was assigned to mouse chromosome 1. Furthermore, the human CNP 5'-flanking region was extended for sequencing, and comparison of the mouse and human CNP genomic sequences revealed regions of conservation and diversity. Using somatic hybrid cell methodology, the CNP gene (NPPC) was assigned to human chromosome 2. The present study has added another locus to the conserved syntenic group in mice and humans.

Natriuretic peptide clearance receptor is transcriptionally down-regulated by beta 2-adrenergic stimulation in vascular smooth muscle cells

Three natriuretic peptide receptors (the ANP-A, ANP-B, and clearance (C) receptors) have been reported. The regulation of these receptors by catecholamines was examined in cultured rat vascular smooth muscle cells. Treatment with norepinephrine decreased the maximum 125I-ANP binding. The competitive binding assay with des[Gln18,Ser19,Gly20,Leu21, Gly22]ANP-(4-23)-NH2 (C-ANF-4-23), a specific ligand for the C receptor, revealed that the decrease in the 125I-ANP binding by norepinephrine was caused by the down-regulation of the C receptor. Isoproterenol also down-regulated the C receptor in a time- and dose-dependent manner. The catecholamine-induced down-regulation of the C receptor was antagonized by a beta 2-selective adrenergic antagonist, ICI 118,551 but not by an alpha 1-, alpha 2-, or beta 1-adrenergic antagonist. Forskolin, NaF and, 8-bromo-cyclic AMP also decreased the C receptor density. The isoproterenol-induced decrease in the C receptor level was further confirmed by affinity cross-linking and Western blot analysis. Northern blot analysis revealed that isoproterenol and 8-bromo-cyclic AMP decreased the steady-state level of C receptor mRNA. By contrast, neither the ANP-A receptor nor the ANP-B receptor mRNA level was affected by 8-bromo-cyclic AMP. The nuclear run-on assay showed that the transcriptional rate of the C receptor gene was decreased by isoproterenol, whereas those of the ANP-A and ANP-B receptor genes were unchanged. Isoproterenol attenuated the clearance of exogenously added ANP and augmented the ANP-stimulated intracellular cyclic GMP production to the same extent as the selective occupancy of the C receptor with C-ANF-(4-23), suggesting that the isoproterenol-induced enhancement of responsiveness to ANP could result not from the sensitization of the ANP-A or ANP-B receptor but from the down-regulation of the C receptor, which leads to the attenuated clearance of ANP. These findings suggest that the beta 2-adrenergic receptor stimulation down-regulates the C receptor through the decrease in the transcriptional rate of the C receptor gene and that the activation of the sympathetic nervous system augments the biological responsiveness to natriuretic peptides by attenuating their metabolic clearance in vascular walls.

An automated method to assess the distribution of low attenuation areas on chest CT scans in chronic pulmonary emphysema patients

We developed an automated method to recognize the lung in a computed tomographic (CT) image. With computer-assisted analysis, we were able to describe the continuous low attenuation (less than -960 Hounsfield units) areas (CLA) on chest CT scans. The size (CLAs) and number (CLAn) of the CLA and the percentage of total lung area occupied by low attenuation area (LAA%) were measured using CT scans obtained from 24 patients with chronic pulmonary emphysema (CPE) and 13 control patients. The automated algorithm recognized the lung areas successfully in all patients. The CLAs and LAA% were significantly higher, and CLAn was significantly lower in patients with CPE than in controls. There was a significant correlation between CT parameters and pulmonary function test results. The histograms of the size of CLA could be represented as a power function in each patient. This automated method should be useful in objectively defining the affected areas in the lungs of patients with CPE.

Impaired vasodilation of peripheral arteries in response to acetylcholine in human beings with abdominal aortic aneurysm

PURPOSE

Most aneurysms are generally presumed to be atherosclerotic in origin. Endothelium-dependent dilations were impaired in the cases of atherosclerosis. It is not clear whether the endothelial function of the peripheral arteries in humans with abdominal aortic aneurysm is impaired. The purpose of this study is to characterize endothelium-dependent relaxations in patients with abdominal aortic aneurysm.

METHODS

Responses of external iliac artery blood flow to acetylcholine (30 micrograms/min: an endothelium-dependent vasodilator) and sodium nitroprusside (10 micrograms/min: a direct dilator of smooth muscle) were examined by electromagnetic blood flow meter in a group of 13 patients consisting of six patients with abdominal aortic aneurysm, six patients with colorectal cancer, and one patient with abdominal aortic aneurysm and rectal cancer.

RESULTS

The mean blood flow before administration of drugs was comparable between the two groups. In the patients with abdominal aortic aneurysm, infusion of acetylcholine did not significantly increase the mean blood flow, whereas in the patients with colorectal cancer, acetylcholine increased the blood flow significantly. The increases of blood flow by an infusion of sodium nitroprusside were comparable between the two groups. In one patient with abdominal aortic aneurysm and rectal cancer, acetylcholine did not alter the blood flow, and sodium nitroprusside increased the blood flow, which was similar to what the patient with abdominal aortic aneurysm experienced.

CONCLUSIONS

These results suggest that in patients with abdominal aortic aneurysm, the endothelium-dependent vasodilations of the peripheral artery were impaired without changing the smooth muscle property.

Functional anatomy of taste perception in the human brain studied with positron emission tomography

Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) in 10 normal volunteers with the purpose of measuring rCBF changes related to taste physiology. Discrimination of 0.18% saline from pure water was associated with significantly increased rCBF values in the thalamus, the insular cortex, the anterior cingulate gyrus, the parahippocampal gyrus, the lingual gyrus, the caudate nucleus, and the temporal gyri. The results indicate that rCBF changes in these structures may reflect oral exposure to salt.

Goblet cell mucins of four genera of the subfamily Cricetinae with reference to the protective activity against Strongyloides venezuelensis

Goblet and mast cell responses in the jejunum of four genera, Mesocricetus auratus (Syrian hamster), Phodopus campbelli, Cricetulus griseus (Chinese hamster), and Tscherskia triton, belonging to the subfamily Cricetinae, were examined after infection with Strongyloides venezuelensis. Parasite eggs became detectable in faeces of all four genera on Day 7. Faecal egg count peaked around Day 8 in C. griseus and T. triton and around Day 14 in M. auratus and P. campbelli. In M. auratus and P. campbelli, faecal egg production persisted over 40 days, whereas that in C. griseus and T. triton rapidly terminated within 14 days. In all four genera examined, goblet cell hyperplasia and mastocytosis were observed at the time of expulsion of S. venezuelensis. However, in the comparative study of all four genera, neither the degree of goblet or mast cell hyperplasia nor the phenotype of mast cells correlated to the rapidity of the expulsion of S. venezuelensis. On the other hand, the rapidity of expulsion closely correlated with the degree of sulphation of goblet cell mucins because two genera, C. griseus and T. triton, having highly sulphated goblet cell mucins showed faster expulsion of S. venezuelensis than the other two genera, P. campbelli and M. auratus, having less sulphated mucins. These results suggest that physicochemical nature of mucins is critical for the expulsion of S. venezuelensis from the subfamily Cricetinae.

Studies on a novel, potent and orally effective cholecystokinin A antagonist, FK-480. Synthesis and structure-activity relationships of FK-480 and related compounds

We prepared various novel tricyclic 1,4-benzodiazepine derivatives as cholecystokinin (CCK) A antagonists, which were evaluated preliminarily for inhibition of 125I-CCK-8 binding to rat pancreatic membranes in vitro and inhibiting effect on CCK-8-induced inhibition of charcoal meal gastric emptying in mice. On the basis of structure-activity relationship (SAR) studies, as well as the stability and availability of the starting materials of those compounds, (S)-N-[1-(2-fluorophenyl)-3,4,6,7-tetrahydro-4-oxo- pyrrolo[3,2,1-jk][1,4]benzodiazepin-3-yl]- 1H-indole-2-carboxamide (9f, FK-480) was selected as a candidate compound for further evaluation. The absolute configuration of the precursor of FK-480, (3S)-amino-1,4-benzodiazepine derivative ((S)-8a, R1 = F) was determined by an X-ray crystallographic study of its ureido derivative with (S)-alpha-methylbenzyl isocyanate. FK-480 is now undergoing clinical studies for the treatment of chronic pancreatitis.

[Integrated diagnosis of small hepatocellular carcinoma with imaging diagnosis]

Herein, we present the diagnostic efficacy of various imaging diagnostic techniques for small liver cancer(HCC) and HCC occurrence predictability by ultrasonography during the follow-up period of chronic liver diseases. During the recent 4 years, 78 nodules of small liver cancer measuring 2 cm or less in diameter were found in 50 patients with liver cirrhosis. In this study, the tumor size was divided into 2 groups; 1.5 cm or less in maximal diameter (group A) and 1.6 to 2 cm (group B). The tumor detectability of ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), angiography and lipiodol CT in group A vs group B was 96% vs 97%, 68% vs 88%, 65% vs 94%, 12% vs 78% and 38% vs 89%, respectively. Therefore, angiography and lipiodol CT were not effective for detection of small HCCs smaller than 1.5 cm. Recently, helical CT scanning has been induced in the diagnosis of HCCs and the tumor detectability was enhanced to 82% even in group A. Additionally, helical-dynamic CT has some advantages in evaluating vascularity, especially arterial feeding which is a specific finding to HCCs. In comparison with contrast-enhanced US using CO2-microbubbles, helical-dynamic CT had equivalent accuracy in diagnosing hypervascular tumors, while hypovascular masses were observed in about 30% of group A. With respect to prediction of HCC occurrence in cirrhotic liver, sonographic evaluation of liver parenchyma seemed to be an important parameter.(ABSTRACT TRUNCATED AT 250 WORDS)

A method to quantitate cerebral blood flow using a rotating gamma camera and iodine-123 iodoamphetamine with one blood sampling

A method has been developed to quantitate regional cerebral blood blow (rCBF) using iodine-123-labelled N-isopropyl-p-iodoamphetamine (IMP). This technique requires only two single-photon emission tomography (SPET) scans and one blood sample. Based on a two-compartment model, radioactivity concentrations in the brain for each scan time (early: t(e); delayed: td are described as: [formula: see text] respectively, where x denotes the convolution integral; Ca(t), the arterial input function; f, rCBF; and Vd, the regional distribution volume of IMP. Calculation of the ratio of the above two equations and a "table look-up" procedure yield a unique pair of rCBF and Vd for each region of interest (ROI). A standard input function has been generated by combining the input functions from 12 independent studies prior to this work to avoid frequent arterial blood sampling, and one blood sample is taken at 10 min following IMP administration for calibration of the standard arterial input function. This calibration time was determined such that the integration of the first 40 min of the calibrated, combined input function agreed best with those from 12 individual input functions (the difference was 5.3% on average). This method was applied to eight subjects (two normals and six patients with cerebral infarction), and yielded rCBF values which agreed well with those obtained by a positron emission tomography H2(15)O autoradiography method. This method was also found to provide rCBF values that were consistent with those obtained by the non-linear least squares fitting technique and those obtained by conventional microsphere model analysis. The optimum SPET scan times were found to be 40 and 180 min for the early and delayed scans, respectively. These scan times allow the use of a conventional rotating gamma camera for clinical purposes. Vd values ranged between 10 and 40 ml/g depending on the pathological condition, thereby suggesting the importance of measuring Vd for each ROI. In conclusion, optimization of the blood sampling time and the scanning time enabled quantitative measurement of rCBF with two SPET scans and one blood sample.

cDNA sequencing of mouse alpha 1-microglobulin/inter-alpha-trypsin inhibitor light chain and its expression in acute inflammation

A cDNA encoding alpha 1-microglobulin (alpha 1mG)/inter-alpha-trypsin inhibitor light chain (ITI-LC) was cloned from mouse liver by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. Sequence analysis of the cDNA showed that the basic molecular structure of the proprotein was similar to that in other animals, so that two mature proteins, alpha 1mG and ITI-LC, could be produced from the proprotein translated from the mRNA. Since ITI-LC is known as a positive acute phase reactant and since ITI-LC is genetically identical with mast cell proteinase inhibitor, trypstatin, we examined the mRNA level in the liver of parasite-infected mice showing extensive mastocytosis. The mRNA level was, however, not significantly changed during inflammatory processes, except for a slight increase on day 8 post-infection.

Molecular cloning of human prostacyclin receptor cDNA and its gene expression in the cardiovascular system

BACKGROUND

Prostacyclin elicits a potent vasodilation and inhibition of platelet aggregation through binding to its membrane receptor. The impairment of prostacyclin receptor activity is implicated in various human cardiovascular diseases. In the present study, we succeeded in the isolation and characterization of human prostacyclin receptor cDNA and elucidated its gene expression in human tissues.

METHODS AND RESULTS

We isolated a cDNA clone encoding the human prostacyclin receptor from a human lung cDNA library. The isolated cDNA clone encodes a 386-amino acid protein with seven putative transmembrane domains, which belongs to the G protein-coupled receptor superfamily. [3H]iloprost, a prostacyclin receptor agonist, specifically bound to the receptor transiently expressed in COS-7 cells. The binding was inhibited in the rank order of iloprost = cicaprost, another prostacyclin receptor agonist, > prostaglandin E1 (PGE1) >> PGE2, PGF2 alpha, PGD2, STA2. In addition, iloprost dose-dependently stimulated cAMP generation in these COS-7 cells. These results are consistent with the characteristics of the human prostacyclin receptor. Northern blotting analysis on human tissues revealed that prostacyclin receptor mRNA is abundantly expressed in the aorta, lung, atrium, ventricle, and kidney.

CONCLUSIONS

We cloned human prostacyclin receptor cDNA and elucidated its abundant gene expression in the human cardiovascular system. The present study will lead to better understanding of the significance of prostacyclin in humans and further facilitate the clinical application of prostacyclin.

Intimal hyperplasia of experimental autologous vein graft in hyperlipidemic rabbits with poor distal runoff

Poor distal runoff and hyperlipidemia are factors affecting the fate of an implanted graft. In the present study, combined effects of poor distal runoff and hyperlipidemia on intimal hyperplasia (IH) of the vein graft were examined in a newly developed poor distal runoff model in rabbits. A poor distal runoff model was prepared in the right hindlimb of 30 rabbits. These animals were divided into two groups, depending on the diet provided; normolipidemic diet group (Group NL, n = 14) and hyperlipidemic 1% cholesterol diet group (Group HL, n = 16). Four weeks after preparing the poor runoff model, the femoral vein was implanted into the ipsilateral femoral artery. At 2, 4 and 6 weeks, the grafts were harvested. IH of the graft was measured and macrophages in the IH were examined immunohistochemically. Intimal cell proliferation was also determined by bromodeoxyuridine (BrdU) incorporation. IH of the vein graft was significantly accelerated in cases of poor distal runoff and hyperlipidemia. There were no macrophages in the IH in the NL group. In the HL group, macrophages infiltrated the outer layer of IH, sometimes just above the internal elastic lamina, and increased with time. In the poor distal runoff limbs at 6 weeks, macrophages also appeared in the subendothelial layer but were absent in that layer in the controls. Intimal cell proliferation expressed as the BrdU labeling index (LI) was maximum at 2 weeks. In the HL group, BrdU LI of IH in the poor distal runoff limb was higher than in the control at 2 and 4 weeks. Throughout the experiments, BrdU LIs in the HL group were significantly higher than in the NL. Hyperlipidemia accelerates intimal cell proliferation to a greater extent, then does IH. In cases of a poor distal runoff, the enhancement of cell proliferation by hyperlipidemia is augmented. These responses, in the presence of a hyperlipidemia, may be closely related to the migration of macrophages.

Therapeutic effect of reticuloendothelial system (RES)-avoiding liposomes containing a phospholipid analogue of 5-fluorouracil, dipalmitoylphosphatidylfluorouridine, in Meth A sarcoma-bearing mice

Reticuloendothelial system (RES)-avoiding liposomes are known to accumulate in tumor tissues due to passive targeting. Dipalmitoylphosphatidylfluorouridine (DPPF), a potent antitumor agent readily incorporated into the lipid bilayer, was embedded in RES-avoiding liposomes modified with a uronic acid derivative, palmityl-D-glucuronide (PGlcUA). The therapeutic effect of DPPF in PGlcUA-liposomes was examined in tumor-bearing mice. Free or liposomal DPPF was injected intravenously into BALB/c mice bearing subcutaneously implanted Meth A sarcomas. The RES-avoiding liposomal formulation using PGlcUA was effective in reducing tumors, and prolonging survival time compared with free DPPF and also DPPF in conventional liposomes. Therefore, PGlcUA-liposomes might be of practical use as drug carriers for anticancer agents, especially their derivatives for embedding in liposomal membranes.

Inhibitory action of a (1-->6)-beta-D-glucan-protein complex (F III-2-b) isolated from Agaricus blazei Murill ("himematsutake") on Meth A fibrosarcoma-bearing mice and its antitumor mechanism

The effects of F III-2-b (Agaricus blazei Murill polysaccharide) with or without 5-fluorouracil (5-FU) on immune responses were investigated in Meth A tumor-bearing and normal mice. The i.p. administration of F III-2-b (10 mg/kg/day x 30) moderately inhibited the growth of Meth A tumor cells implanted s.c. in mice. Development of implanted tumors was strongly inhibited by the combination of F III-2-b and 5-FU. The picryl chloride-induced delayed type hypersensitivity (PC-DTH) response in mice was depressed after the implantation of tumor and treatment with 5-FU. F III-2-b restored the suppression of PC-DTH by 5-FU, but did not increase the PC-DTH of normal mice. F III-2-b not only enhanced the degree of spleen cell-mediated sheep red blood cells (SRBC) hemolysis (quantitative hemolysis of SRBC), the indexes of the spleen and thymus, and the number of spleen cells but also restored the suppressive effect of 5-FU. In the group receiving F III-2-b, the percentages of splenic Thy1.2-, L3T4- and asialo GM1-positive cells were significantly increased as compared with the tumor-bearing mice treated with saline. Furthermore, the L3T4+/Lyt2+ ratio showed a tendency to increase, and the Lyt2+ ratio was markedly decreased. These results suggest that the antitumor effect of F III-2-b may be correlated with the changing pattern of the Thy1.2-, L3T4- and asialo GM1-positive cells.

Molecular cloning of hamster brain and atrial natriuretic peptide cDNAs. Cardiomyopathic hamsters are useful models for brain and atrial natriuretic peptides

Brain and atrial natriuretic peptides (BNP and ANP) are cardiac hormones with diuretic, natriuretic, and vasodilatory activities. Cardiomyopathic hamsters are widely used animal models of heart failure. Due to the structural divergence of BNP among species, examination on pathophysiological roles of BNP using cardiomyopathic hamsters is so far impossible. We therefore isolated hamster BNP and ANP cDNAs, and investigated synthesis and secretion of these peptides in normal and cardiomyopathic hamsters. The COOH-terminal 32-residue peptide of cloned hamster preproBNP with 122 amino acids, preceded by a single arginine residue, supposedly represents hamster BNP showing < 50% homology to rat BNP. Alpha-hamster ANP, 28-residue peptide, is identical to alpha-rat ANP. In hamsters, BNP and ANP occur mainly in the ventricle and the atrium, respectively. The 32-wk-old hypertrophic cardiomyopathic BIO14.6 strain exhibited ventricular hypertrophy. The 32-wk-old dilated cardiomyopathic BIO53.58 strain remained at the stage without apparent heart failure. In BIO14.6 and BIO53.58 strains at this age, ventricular BNP and ANP gene expressions are augmented, and the plasma BNP concentration is elevated to 136 and 108 fmol/ml, respectively, three times greater than the elevated plasma ANP concentration, which well mimics changes of the plasma BNP and ANP concentrations in human heart failure. Cardiomyopathic hamsters, therefore, are useful models to investigate the implication of BNP in human cardiovascular diseases.