Protein kinase C-dependent modulation of stimulatory guanine nucleotide binding protein of fetal rat skin keratinocytes

Although the protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA) has been known to induce heterologous desensitization of the epidermal adenylate cyclase, the precise mechanism of PMA action remains unknown. Effects of PMA on the receptor-G-protein-adenylate cyclase system of fetal rat skin keratinocytes (FRSK) were investigated. Choleratoxin catalysed the ADP ribosylation of 45 kDa and 52 kDa membrane proteins and islet activating protein (IAP) catalysed the ADP ribosylation of a 40 kDa membrane protein. Incubation of FRSK with PMA decreased the cholera toxin-catalysed ADP ribosylation of the membrane protein, but not the IAP-catalysed ADP ribosylation. The effect of PMA on the cholera toxin-catalysed ADP ribosylation was inhibited by the PKC inhibitor, H-7 (1-(5-isoquinolinesulfonyl)-2-methyl piperazine dihydrochloride). 1-Oleoyl-2-acetylglycerol (OAG), a membrane-permeable diacylglycerol analogue, also decreased the cholera toxin-catalysed ADP ribosylation, but 4-0-methyl PMA, a very weak PKC activator, had no effect. Keratinocytes are known to express the guanine nucleotide binding proteins, Gsalpha, Gi2alpha, and Gi3alpha. Immunoblot analysis of the PMA-treated FRSK showed no detectable difference in the amount of Gsalpha, Gi2alpha, Gi3alpha, or the beta subunit of the G-protein. PMA significantly decreased the beta-adrenergic adenylate cyclase response and cholera toxin-induced cyclic AMP accumulation, while it markedly increased forskolin-induced cyclic AMP accumulation. These results indicate that phorbol esters affect the stimulatory guanine nucleotide binding protein (Gs) of FRSK via a PKC-dependent pathway.

Combined chemotherapy and radiation therapy in head and neck cancer

A combination chemotherapy (PT treatment) with cisplatin and tetrahydropyranyl-adriamycin (THP-ADM) was performed in 17 patients with head and neck squamous cell carcinoma. Chemotherapy treatment began with an intravenous dose of 50 mg/body cisplatin and an intravenous dose of 20 mg/body THP-ADM. Administration of THP-adriamycin was performed on the first day only, while cisplatin treatment was repeated once a day until the third day. Five of the 17 cases achieved complete response (29.4%) and seven achieved partial response. Response rate was 70.6%. Toxicity was mild and controlled with symptomatic treatment. Leukopenia was observed in 71.4% thrombocytopenia 14.3% (due to myelosuppression), appetite loss 38.1%, general fatigue 28.6% and nausea and vomiting 23.8%. No electrocardiographic abnormality was noted.

High susceptibility of U937-derived subclones to human immunodeficiency virus type 1 infection correlates with accumulation of unintegrated circular viral DNA

Our previous report showed that U937-derived subclones were differentiated into at least three types (high, middle, and low types), even in the subclones expressing similar levels of surface CD4, in terms of the kinetics of the appearance of viral antigens and virus production after infection with human immunodeficiency virus type 1 (HIV-1). Here we showed the evidence that high susceptibility to HIV-1 infection, which was confirmed by the profound expression of viral messages and antigens, was exclusively associated with a high number of the unintegrated extrachromosomal form of viral DNA, but not with the amounts of adsorbed virus RNA nor those of integrated DNA form. The difference in the amounts of extrachromosomal form of viral DNA was also observed in the culture with 3'-azido-3'-deoxythymidine (AZT), indicating that the susceptibility is essentially unrelated to multiple infection events. Thus, the susceptibility of U937-derived subclones to HIV-1 infection seems to be affected by the occurrence of specific events involved in the accumulation of unintegrated viral DNA after viral adsorption.

A cervical dural arteriovenous fistula in a patient presenting with radiculopathy. Case report

A 51-year-old man presenting with radiculopathy a rare cervical dural arteriovenous fistula (AVF) is reported. Angiography revealed that the cervical dural AVF was fed mainly by the left C-3 and C-4 radicular arteries and drained into the internal vertebral venous plexus with no communication with intradural structures. The dural AVF was treated surgically after embolization therapy. Although the AVF showed mass effect on computerized tomography (CT) scanning, abnormal vessels, which were suspected to drain the AVF, were observed intraoperatively to compress the left C-4 and C-5 nerve root sleeves. After resection of these abnormal epidural vessels, monoparesis of the left proximal upper extremity was markedly improved. In this patient, dynamic CT scanning was useful in the initial diagnosis, and the preoperative embolization therapy was very effective.

Comparison of surface antigens on eosinophils from patients with eosinophilia

Recent studies have suggested that there may be heterogeneity among human eosinophils. To study this further, surface antigens on blood eosinophils from patients with eosinophilia (23 bronchial asthma, 6 eosinophilic pneumonia, 1 Kimura's disease and 1 adult T-cell leukemia) and from 8 control subjects were examined using a new direct method for fluorescence detection of eosinophils. HLA-DR+ and CD4+ eosinophil counts were higher in patients with bronchial asthma and adult T-cell leukemia (ATL) than in patients from other groups and in control subjects. CD11b+ eosinophil counts in Kimura's disease and ATL were smaller than those in the other groups. CD45RO+ eosinophil counts in bronchial asthma and eosinophilic pneumonia were significantly higher (p < 0.05) compared with Kimura's disease, ATL and control subjects. CD44+ eosinophil counts in eosinophilic pneumonia were significantly higher (p < 0.05) compared with the other groups and control subjects. These results suggest the existence of functional heterogeneity in the different eosinophilic diseases, with eosinophils in bronchial asthma and eosinophilic pneumonia being more highly activated in migration, activation and immunoregulation. On the other hand, eosinophils in Kimura's disease and ATL might be functionally down-regulated. This heterogeneity of eosinophils may reflect differences in the pathogenesis of various eosinophilic diseases.

Sarcoidosis presenting as a scarring alopecia: report of a rare cutaneous manifestation of systemic sarcoidosis

We report a 51-year-old woman with alopecia caused by sarcoidosis. The lesion enlarged within 4 years and only repeated biopsies enabled the diagnosis. The medical work-up revealed that the patient had asymptomatic pulmonary involvement. Scarring alopecia is a rare complication of sarcoidosis and biopsy from the active margin may lead to the diagnosis.

Nucleotide sequences of the M gene of prevailing wild measles viruses and a comparison with subacute sclerosing panencephalitis virus

We determined the nucleotide sequences of the coding region for the M gene in seven strains of measles virus (MV) that were isolated in Japan between 1984 and 1993. The mutation found among the seven differed from those of laboratory strains. Many of these mutations were the same as those that are characteristic of SSPE viruses. Thus, we suggest that the mutations that have been considered specific to SSPE virus are in fact consensus among prevailing MV.

Towards more practical average bounds on supervised learning

In this paper, we describe a method which enables us to study the average generalization performance of learning directly via hypothesis testing inequalities. The resulting theory provides a unified viewpoint of average-case learning curves of concept learning and regression in realistic learning problems not necessarily within the Bayesian framework. The advantages of the theory are that it alleviates the practical pessimism frequently claimed for the results of the Vapnik-Chervonenkis (VC) theory and its alike, and provides general insights into generalization. Besides, the bounds on learning curves are directly related to the number of adjustable system weights. Although the theory is based on an approximation assumption, and cannot apply to the worst-case learning setting, the precondition of the assumption is mild, and the approximation itself is only a sufficient condition for the validity of the theory. We illustrate the results with numerical simulations, and apply the theory to examining the generalization ability of combination of neural networks.

Expression of p34cdc2 protein kinase and p53 in supraglottic carcinomas

The clinicopathological significance of the simultaneous expression of the p34cdc2 protein kinase oncogene product and mutant-type p53 oncogene product was studied in 15 supraglottic squamous cell carcinomas. Clinical and histopathological data were recorded from the medical records, and immunohistochemical and DNA cytofluorometric analysis were performed. p34cdc2 was positive in 80% and mutant-type p53 in 53% of the tumors. Their simultaneous expression was seen in 33% of the tumors, but the probability was not statistically significant. Correlations between the expression of p34cdc2 or mutant-type p53 and T, N categories, histological differentiation, and DNA ploidy pattern were not significant. However, when the percentages of p34cdc2 and mutant-type p53-positive cells in the tumor were high, aneuploidy tended to be present and the clinical stage more advanced. It is suggested that the growth and progression of supraglottic carcinomas are associated with the disruption of the regulatory system of the cell cycle.

Endogenous nitric oxide production is augmented as the severity advances in patients with liver cirrhosis

1. Since endothelium-derived nitric oxide (NO) is a potent vasodilator and degraded into nitrous ions, we measured the serum nitrate ion (NO3-) and the amount of urinary excretions of NO3- as an index for endogenous NO to ascertain whether NO formation is augmented in patients with chronic liver diseases. 2. Using inpatients suffering from chronic liver diseases, serum levels and urinary excretions of NO3- were measured by using high-performance liquid chromatography with an anion exchange column. 3. Among the four patient groups of normal controls, and those with chronic liver diseases such as chronic active hepatitis, compensated cirrhosis, and decompensated cirrhosis the serum level of NO3- showed the highest level in a patient group with decompensated cirrhosis. The amount of urinary excretion of NO3- was significantly increased in both groups of patients with liver cirrhosis compared with the control group and patients with chronic active hepatitis. Patients with chronic active hepatitis did not show any difference between the normal control group. The amount of urinary excretion of NO3- correlated significantly and negatively with the level of serum albumin (P < 0.05) and counts of platelets (P < 0.01) in patients with compensated cirrhosis. 4. These findings suggest that the production of endogenous NO is augmented in patients with liver cirrhosis, particularly in a decompensated subgroup. Increases in the production of endogenous NO correspond to the progress of liver cirrhosis, but not in patients with chronic hepatitis.

Inhibitory effects of selenium, vitamin A and butylated hydroxytoluene on growth of human maxillary cancer cells in vitro

The effects of vitamin A, selenium, and butylated hydroxytoluene (BHT) on the growth of a human maxillary cancer cell line were examined in monolayer cell cultures. The colony-forming assay showed a 50% reduction in the survival rate of the cell line at a concentration of 3.6 micrograms/ml of selenium, 28 micrograms/ml of vitamin A, and 74 micrograms/ml of BHT. Flow cytometric analysis with both FITC-labeled bromodeoxyuridine monoclonal antibody and propidium iodide demonstrated an increase of the S-phase fraction in the presence of selenium, an increase of the G0/G1-phase fraction in the presence of vitamin A, and an increase of the G2-M-phase fraction 1 day followed by an increase of G0/G1-phase fraction from the 3rd to 7th day when BHT was added. These results suggest that the mechanisms of inhibition of DNA synthesis by these compounds are different.

Expression of prothrombinase activity and CD9 antigen on the surface of small vesicles from stimulated human endothelial cells

We employed flow cytometry and monoclonal antibodies (MoAb) to study the surface membrane protein of shed particles (small vesicles, SV) that were released from vascular endothelial cells (EC) by agonists such as a Ca ionophore (A23187) and thrombin. After stimulation of EC by A23187, CD9 antigens disappeared entirely from the EC surface in a time- and concentration-dependent manner; they subsequently moved onto the SV surface. Von Willebrand factor (vWF) and P-selectin from Weibel-Palade (W-P) bodies were expressed rapidly on the EC surface after thrombin stimulation, but not on the SV surface. P-selectin may have some effect on maintenance of hemostasis on the EC surface. We demonstrated that the surfaces of SV and EC significantly supported prothrombinase activity and confirmed that A23187-induced SV from EC express binding sites for factors IXa and Xa. These results suggest that the SV are an important factor in a novel controlling mechanism of the coagulation system on the EC surface.

Identification of Rap1 as a target for the Crk SH3 domain-binding guanine nucleotide-releasing factor C3G

C3G, which was identified as a Crk SH3 domain-binding guanine nucleotide-releasing factor, shows sequence similarity to CDC25 and Sos family proteins (S. Tanaka, T. Morishita, Y. Hashimoto, S. Hattori, S. Nakamura, M. Shibuya, K. Matuoka, T. Takenawa, T. Kurata, K. Nagashima, and M. Matsuda, Proc. Natl. Acad. Sci. USA 91:3443-3447, 1994). The substrate specificity of C3G was examined by in vitro and in vivo experiments. C3G markedly stimulated dissociation of bound GDP from Rap1B but marginally affected the same reaction of other Ras family proteins (Ha-Ras, N-Ras, and RalA). C3G also stimulated binding of GTP-gamma S [guanosine 5'-3-O-(thio)triphosphate] to Rap1B. When C3G and Rap1A were expressed in COS7 cells, marked accumulation of the active GTP-bound form of Rap1A was observed, while Sos was not effective in the activation of Rap1A. These results clearly show that C3G is an activator for Rap1. Furthermore, expression of C3G with a membrane localization signal in a v-Ki-ras transformant, DT, induced a reversion of the cells to the flat form, possibly through the activation of endogenous Rap1.

The influence of scattering on temporo-regional proliferation in the cultured Madin-Darby canine kidney (MDCK) cells

An epithelial Madin-Darby canine kidney (MDCK) cell line was grown in two kinds of standard media and a medium conditioned by MRC-5 embryonic lung cells, and temporo-regional differences in cell proliferation were examined by immunohistochemical detection of incorporated bromodeoxyuridine (BrdU). MRC-5-conditioned medium is known to contain scatter factor, which induces scattering of MDCK cells. In a proliferation assay, the BrdU labeling index (percentage ratio of BrdU-positive to total nuclei) was highest in day 2 cultures in the standard media, but on day 3 in the conditioned medium. MDCK cells in the standard media formed multiple epithelial sheets by day 2. In the conditioned medium, however, epithelial sheet formation was retarded and observed only after day 3. Once epithelial sheets had formed, cells close to the edge of the sheet were more proliferative than those distant from the edge in both standard and conditioned media. These findings suggest that proliferation of MDCK cells is suppressed during the scattering induced by the conditioned medium, and that their DNA synthesis becomes most active when cell scattering has ceased and epithelial sheets have begun to form.

Pulmonary surfactant protein D in sera and bronchoalveolar lavage fluids

Pulmonary surfactant protein D (SP-D) is a hydrophilic glycoprotein with a reduced molecular mass of 43 kDa and a member of the C-type lectin superfamily, along with mannose-binding proteins and surfactant protein A (SP-A). We have recently prepared monoclonal antibodies against human SP-D and developed an enzyme-linked immunosorbent assay (ELISA). In this study, the levels of SP-D in sera and bronchoalveolar lavage (BAL) fluids of patients with lung diseases were determined by ELISA, using human recombinant SP-D as a standard. We demonstrated that the concentrations of SP-D in sera are prominently increased in patients with idiopathic pulmonary fibrosis (IPF), interstitial pneumonia with collagen disease (IPCD), and pulmonary alveolar proteinosis (PAP). Patients with IPF, IPCD, and PAP exhibited levels of serum SP-D 5.1-fold, 7.2-fold, and 7.0-fold, respectively, of those in healthy volunteers; 91.5% of the patients with IPF, 81.3% with IPCD, and 100% with PAP exhibited serum SP-D levels that exceeded the cut-off value (mean + 2 SD of control value). Serum SP-D levels appeared to reflect the disease activity of IPF and IPCD and the disease severity of PAP. High levels of SP-D in BAL fluids were shown in patients with PAP, but not with IPF and IPCD. We conclude that measurement of SP-D in sera can provide an easily identifiable and useful clinical marker for the diagnosis of IPF, IPCD, and PAP, and can predict the disease activity of IPF and IPCD and the disease severity of PAP.

Nucleolar organizer regions in glottic carcinomas: comparison of DNA cytofluorometry and clinicopathological analysis

The significance of nucleolar organizer regions (NORs) and nuclear DNA content in 73 glottic carcinomas was assessed for proliferative activity and tumor progression. NORs stained with silver colloid were counted, and nuclear DNA content was assayed by cytofluorometry. The cytofluorometric study demonstrated that the percentage of tumors with aneuploidy tended to increase as histological differentiation decreased. Survival rates of patients with diploid and aneuploid tumors were not significantly different. AgNOR staining revealed that mean AgNOR numbers rose as histological differentiation of tumors decreased. Moreover, as T and N categories and stages showed advancing malignancy, mean AgNOR numbers tended to rise. However, there was no significant difference in survival rates between tumors with low and with high AgNOR counts. These studies indicate that while AgNOR staining is better than DNA cytofluorometry for determining histological differentiation of glottic carcinoma, neither is of prognostic value at the present time.

Inhibitory effects of selenium, vitamin A and butylated hydroxytoluene on in vitro growth of human tongue cancer cells

The effects of vitamin A, selenium and butylated hydroxytoluene (BHT) on the growth of a human tongue cancer cell line were examined in monolayer cell cultures. A colony-forming assay showed a 50% reduction in the survival rate of the cell line at a concentration of 2.6 micrograms/ml selenium, 60 micrograms/ml vitamin A and/or 38 micrograms/ml BHT. Relatively low concentrations of selenium markedly inhibited glucose consumption. Flow cytometric analysis with both fluorescein-isothiocyanate-labelled bromodeoxyuridine monoclonal antibody and propidium iodide demonstrated an increase in S-phase fractions 1 day after the addition of selenium, increased G0/G1 phase fractions in the presence of vitamin A and increased G2-M phase fractions when BHT was added. These results suggest that these compounds inhibit DNA synthesis of in vitro human tongue cancer cells by different mechanisms.

Vascular changes in major and lingual minor salivary glands in primary Sjögren's syndrome

A histological investigation of the vascular changes of three major and lingual minor salivary glands in primary Sjögren's syndrome was carried out on eight autopsied Japanese patients. This study compares vascular lesions in salivary glands between one group of four short-term corticosteroid-treated patients (Cases 1, 3, 4 and 7) and the other group of four long-term corticosteroid-treated patients (Cases 2, 5, 6 and 8). We proposed the following five stages for morphogenesis of arteritis; (1) endothelial swelling, (2) thrombosis, (3) fibrinoid degeneration, (4) necrotizing panarteritis and (5) endarteritis obliterans. Endothelial swelling was seen in small-to-large arteries of major salivary glands and the tongue, and this finding was considered as the initial change of vascular lesion. Thrombosis was observed in the small arteries of both organs. Fibrinoid degeneration and necrotizing panarteritis were predominantly localized in small and middle-sized arteries. Endarteritis obliterans was observed in small and large arteries of major and lingual minor salivary glands in primary Sjögren's syndrome. Vascular lesion of this type was common in the four patients who received corticosteroid for more than 12 months. Corticosteroid therapy appears to accelerate the fibrotic change of the vascular wall. Therefore, we suggest that essential vascular lesions of major and lingual minor salivary glands in primary Sjögren's syndrome may include four types (endothelial swelling, thrombosis, fibrinoid degeneration and necrotizing panarteritis), excluding endarteritis obliterans.

[Activated coagulation factors in various thrombotic diseases]

Various hemostatic abnormalities have been reported and excess activation of coagulation factors, such as prothrombin, factor VII, factor IX, and factor XI, have been detected in thrombotic diseases states by various assay systems. We recently developed the enzyme-linked differential immunoassay for activated factor XI-alpha 1 antitrypsin complex (FXIa-alpha 1 AT) and applied it with other assays for activated factors such as thrombin-antithrombin III complex (TAT) to detect the hypercoagulable state in clinical samples. In patients with DIC, the FXIa-alpha 1 AT level in plasma increased before onset of DIC. In patients with non-insulin-dependent diabetes mellitus, FXIa-alpha 1AT and TAT levels were increased in the patient plasma. FXIa-alpha 1AT was related to the severity of urinary albumin excretion, whereas TAT was not. Plasma FXIa-alpha 1AT levels were significantly increased in patients with angiographically proven coronary artery disease, and showed a positive correlation with TAT, fibrinogen, and Lp(a). Evaluation of activated coagulation factor provides useful information on the diagnosis of thrombotic disease.

Mechanism of hypertension induced by chronic inhibition of nitric oxide in rats

In order to clarify the mechanism of hypertension induced by a nitric oxide (NO) synthase inhibitor, L-NG-nitro-L-arginine (LNNA), metabolites of NO, catecholamines, and hemodynamic parameters were measured during 7 days of oral administration of LNNA in rats. Control rats received either L-arginine (L-Arg) or the vehicle. systolic blood pressure, measured by the tall-cuff method was elevated throughout the period of LNNA administration, but that in the two control groups was not influenced by treatment. Heart rate decreased on the second day only in LNNA-treated rats. Although L-Arg treatment had no influence, LNNA markedly decreased the plasma level and the urinary excretion of nitrate ions (NO-3). Urinary excretion of noradrenaline was significantly decreased on the second day of LNNA administration and returned to the control level thereafter. When hemodynamic changes were measured by using radioactive microspheres, LNNA was found to increase blood pressure by markedly increasing total peripheral resistance. Cardiac output was decreased by LNNA. L-Arg, again, did not influence the hemodynamic variables as compared with the vehicle control group. The regional vascular resistance index was increased by LNNA in many tissues and organs, except the brain and the heart. Regional blood flow, on the other hand, was significantly decreased only in the liver and skin by LNNA. The marked reduction in NO3- in urine by LNNA-treatments may indicate that the measured NO3- is exclusively of endogenous origin, and that inhibition of NO production causes elevation of blood pressure by constricting peripheral arteries. Sympatholytic responses by the baroreceptor reflex were thereby evident only on the second and the third days, which was indicated by bradycardia and suppression of noradrenaline excretion into urine. These results indicate that the inhibition of NO synthase actually decreases production of endogenous NO, and that the hypertension caused by decreases in NO production is due to elevation of total peripheral vascular resistance.