Hepatocytic phenotypes induced in sarcomatous cholangiocarcinoma cells treated with 5-azacytidine

The sarcomatoid cells found in cholangiocarcinoma (CC) or hepatocellular carcinoma (HCC) are not well characterized. In this study, a human sarcomatoid CC cell line, ETK-1, was established from a patient, and then morphological and phenotypical characteristics of the ETK-1 cells were evaluated before and after treatment with differentiation-inducing 5-azacytidine (5-azaCR). Phenotypically, the ETK-1 cells appeared immature. Exposure to 5-azaCR induced morphological transformation; a converted cell line, MEK, was successfully established. The MEK cells expressed such hepatocyte-specific proteins as alpha-fetoprotein, albumin, integrin alpha1, and thrombopoietin, but lost such bile duct-specific proteins as integrin alpha3 and integrin beta4. The histopathology of MEK xenografts resembled that of HCC. The ETK-1 cells appeared to be converted into hepatocytes by exposure to 5-azaCR. On the other hand, ETK-1 xenografts were diagnosed as tubular adenocarcinoma, and the tumor cells had a ductal phenotype. This suggests the possibility that ETK-1 cells can differentiate along a biliary epithelial cell lineage. ETK-1 and MEK will be useful in studying hepatocytic differentiation and the transformation from a biliary epithelial cell to a hepatocytic lineage.

32P-postlabelling of aromatic DNA adducts in white blood cells and alveolar macrophages of smokers: saturation at high exposures

DNA adducts may serve as a molecular dosimeter of exposure to cigarette smoke-associated carcinogens such as polycyclic aromatic hydrocarbons (PAH). Target tissues for cigarette smoke-induced carcinogenesis are rarely accessible; therefore, peripheral blood cells or cells obtained by bronchoalveolar lavage (BAL) may be used as surrogate sources of exposed DNA. However, the relationship between cigarette smoke exposure and aromatic-DNA adducts in white blood cells and BAL cells is still unclear. In this study, we examined DNA adduct formation in lymphocytes and BAL cells in several populations of smoking individuals by means of 32P-postlabelling. Significant correlations between the amount of cigarettes smoked per day and the level of aromatic-DNA adducts were found in lymphocytes. In BAL cells, DNA adduct levels were associated with age (p = 0.05) and gender (p = 0.10) after adjustment for smoking behaviour. Adduct formation levelled off at higher exposure levels, suggesting less efficient adduct formation; decreases in the formation of adducts per unit of exposure were found in lymphocytes (r(s) = -0.80, p < 0.001) and BAL cells (r(s) = -0.72, p < 0.001). To assess intra-individual variation in adduct levels at constant smoking behaviour, sampling was repeated after a period of 2 and 6 months. In lymphocytes, repeated measurements with an interval of 2 months were highly correlated (r = 0.84, p = 0.009, n = 8), whereas repeated measurements with an interval of 6 months showed no correlation (r = 0.30, p = 0.27, n = 16). Repeated measurements in BAL cells showed a significant correlation after 6 months (r = 0.68, p = 0.03, n = 10). Furthermore, in a group of occupationally exposed aluminium workers, adduct levels in total white blood cells were correlated with the average concentrations of PAH in the ambient air of workers who smoked cigarettes, whereas in non-smokers, no such relationship was found. We conclude that cigarette smoking may directly or indirectly influence DNA adduct levels and saturation of DNA adduct formation may occur, leading to non-linear dose-response relationships.

Methemoglobin formation in hemoglobin vesicles and reduction by encapsulated thiols

The hemoglobin vesicle (HbV) is a red cell substitute encapsulating purified concentrated Hb in a phospholipid vesicle. In order to suppress metHb formation or autoxidation, for the long-term maintenance of the oxygen transporting capability, a series of thiols (cysteine, Cys; glutathione, GSH; homocysteine, Hcy; and acetylcysteine, Acy) were studied as reductants of metHb. Hcy and GSH showed a good suppressive effect on metHb formation, while Cys adversely accelerates the metHb formation at a rate twice that of the Hb solution without any reductants and Acy showed no change. The significant suppression by the coaddition of superoxide dismutase (SOD) and catalase to Cys indicated that Cys was easily oxidized by oxygen and simultaneously generates a large amount of active oxygens. The effective suppression of metHb formation by SOD and catalase was not observed for HbV containing no reductants, indicating that the generation of active oxygens from Hb itself is not significant. The coencapsulation of Hcy with Hb resulted in a low rate of metHb formation in HbV (initial rate, 1%/h) in vitro at an oxygen partial pressure (Po2) of 142 Torr. The rate increased with decreasing Po2, showed a maximum (2.2%/h) around Po2 = 23 Torr, and then decreased to 0%/h at 0 Torr. From these results, it is suggested that the fast metHb formation rate in the blood circulation of Wistar rats injected with 20 vol % of the HbV solution would be mainly caused by the exposure of HbV to the low Po2.

Diagnostic problems in chronic eosinophilic pneumonia

To identify the problems involved in the diagnosis of chronic eosinophilic pneumonia (CEP), clinical findings were analysed for 43 patients diagnosed clinically or pathologically with CEP during the past 10 years. About 28% of patients showed peripheral blood eosinophilia and a typical pattern of pulmonary oedema on chest X-ray at initial examination. Eosinophilia was demonstrated in peripheral blood in 86% of patients, in bronchoalveolar lavage (BAL) in 100%, and in transbronchial lung biopsy (TBLB) specimens in 64% of patients. Peripheral blood tests, BAL, and TBLB were all positive for eosinophilia in 60% of patients. BAL was the single test most likely to be positive among the diagnostic tests used in the present study. When CEP is suspected clinically, an understanding of which site is examined by each of the diagnostic tests and of the likelihood of a positive result in each test will facilitate the selection of the most appropriate tests for individual patients.

In situ hybridization studies of matrix metalloproteinase-3, tissue inhibitor of metalloproteinase-1 and type IV collagen in diabetic nephropathy

Progressive expansion of the mesangial matrix is one of the most characteristic histological features of diabetic nephropathy (DN). To determine the balance between the turnover and degradation of extracellular matrix (ECM) in renal tissue of patients with DN, we examined the expression of matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1) and type IV collagen (IV-C) mRNAs using a high-resolution in situ hybridization. Patients were divided into three grades: mild (grade I), moderate (grade II) and severe (grade III) mesangial expansion and tubulointerstitial injury. The relationship between the expression of these mRNAs and degree of glomerular mesangial expansion and interstitial injury was also examined. Cells positive for each mRNA were observed in glomerular resident cells, including glomerular mesangial, epithelial and endothelial cells and cells of Bowman's capsule. A number of tubular epithelial cells and some infiltrating cells in the interstitium also expressed these mRNAs. The expression of MMP-3 mRNA and TIMP-1 mRNA was strongest in glomeruli of grade I and inversely correlated with mesangial expansion. In contrast, the expression of all three types of mRNA was correlated with the degree of interstitial injury. Our results indicate that IV-C, MMP-3 and TIMP-1 mRNAs are expressed in glomerular resident cells, tubular epithelial cells and infiltrating cells in renal tissue of DN, and suggest that their expression changes with the degree of mesangial expansion and interstitial injury. Altered expression of MMP-3 and TIMP-1 may be associated with the progression of DN.

Autoimmune pancreatitis as a new clinical entity. Three cases of autoimmune pancreatitis with effective steroid therapy

The most common forms of chronic pancreatitis are related to alcohol ingestion, whereas the entity of non-alcohol-associated (idiopathic) pancreatitis is poorly understood. Autoimmunity has been suggested as a possible etiologic factor of idiopathic chronic pancreatitis. A total of 362 Japanese patients underwent endoscopic retrograde pancreatography (ERP) for suspected pancreatic disease, and 161 were diagnosed with chronic pancreatitis. Among them, we found three cases (1.86% incidence) of unique chronic pancreatitis, in which ERP revealed diffuse narrowing of the main pancreatic duct with an irregular wall. We diagnosed these three patients as having pancreatitis associated with an autoimmune mechanism morphologically and biochemically and started them on steroid therapy. The characteristics of the these three patients were as follows: hypergammaglobulinemia, eosinophilia, ultrasonography showing hypoehoic diffuse swelling in the pancreas (sausage-like appearance), ERP showing diffuse narrowing of the main pancreatic duct with irregular like thumbprint-like marks, reversible exocrine insufficiency, and positive anti-carbonic anhydrase II antibody. After one month of the treatment with steroids, pancreatitis dramatically improved morphologically and enzymatically. Here we describe these cases of the suspected autoimmune chronic pancreatitis. We must recognize the concept and the features of autoimmune pancreatitis in order to avoid unnecessary surgery as pancreatic cancer.

The oxygen carrying capability of hemoglobin vesicles evaluated in rat exchange transfusion models

To evaluate the oxygen transporting capability of Hemoglobin vesicles (HbV) the physiological responses to 40% and 90% exchange transfusions with HbV in anesthetized rat were observed. Hb concentration of HbV dispersions is 10 g/dL. HbV dispersed in phosphate buffered saline and HbV dispersed in 5% albumin solution were used as samples for 40% and 90% exchange transfusions, respectively. HbV surface-modified with polyoxyethylene (HbV-Poe) was also used in the 90% exchange transfusion. As controls, phosphate buffered saline, 5% albumin solution, and HbV containing methemoglobin and therefore deprived of oxygen transporting capabilities (metHbV) were administered as non-oxygen carrying fluids and washed rat red blood cells (ratRBC) as an oxygen carrying fluid. Measurements included mean arterial pressure, arterial blood gas analyses, aortic blood flow and renal cortical tissue oxygen tension. At the completion of the exchange transfusion renal cortical tissue oxygen tensions along with oxygen delivery and consumption were sustained almost equally well with the HbV dispersion compared to the washed rat red blood cell dispersion, but declined significantly in the phosphate buffered saline and albumin solutions. These results indicated that the oxygen transporting capability of HbV was almost equivalent to that of rat red blood cells. In the HbV-Poe group, aortic blood flow was sustained higher in comparison to the HbV group. As for the blood gas parameters, pH and venous oxygen tensions in the HbV-Poe group tended to be higher than those in the HbV group.

A Novel Numerical Analysis on Surface Charge Densities of an Amphoteric O/W-Type Microemulsion in the Presence of CaCl2 and/or AlCl3

The effect of pH on the surface charge density of the O/W-type microemulsion formed in solutions of an amphoteric surfactant, (N alpha , N alpha -dimethyl-N epsilon -lauroyllysine, DMLL)/n -octane/1-pentanol/CaCl2 or AlCl3 , has been investigated. A novel equation for the surface charge densities in the presence of a multivalent cation (Ca2+ and/or Al3+ ) has been derived taking account of the number of DMLL molecules bound to a multivalent cation (q ). By applying a numerical analysis of this equation, it is possible to determine the intrinsic binding constants (K ) of the multivalent cation and the monovalent anion to the hydrophilic groups of DMLL and the adsorption density (N ) of DMLL molecules on the oil/water interface. Furthermore, N has been found to show pH dependence. N has a maximum value around the isoelectric region (in particular, pH 5-7) of DMLL molecules in the presence of CaCl2 , whereas N increases with increasing pH in the presence of AlCl3 . The surfactant (DMLL) numbers per O/W-type microemulsion droplet, i.e., the aggregation numbers, are successfully obtained as a function of pH in the presence of CaCl2 and/or AlCl3 .

Evaluation of the capabilities of a hemoglobin vesicle as an artificial oxygen carrier in a rat exchange transfusion model

Encapsulation of hemoglobin within a liposome is one of the strategies in the development of artificial oxygen carriers. It maintains the oxygen transporting properties of hemoglobin and, at the same time, eliminates the side effects of cell free hemoglobin. Hemoglobin vesicles (HbV) are a type of liposome encapsulated hemoglobin. They have a particle size of approximately 250 nm, a hemoglobin concentration of 10 g/dl, and the oxygen affinity, P50, is regulated to 32 Torr. In this study the authors examined the oxygen transporting capability of HbV in vivo, by performing exchange transfusions in rats. Exchange transfusion (90% of the estimated circulatory volume) with HbV suspended in 5% albumin (containing 160 mEq/L, sodium and 107 mEq/L, chloride) was carried out in male Wistar rats. Mean arterial pressure and heart rate were monitored through the arterial catheter. Arterial blood samples for gas analyses were also obtained from the arterial catheter. Abdominal aortic blood flow was measured by an ultrasonic pulsed Doppler flowmeter as an indicator of cardiac output. The oxygen tension of blood withdrawn from the right atrium was measured as an indicator of mixed venous oxygen tension. These values were employed to calculate oxygen delivery and consumption. Renal cortical and skeletal muscle tissue oxygen tensions were monitored as indicators of tissue perfusion. Five percent albumin and washed rat red blood cells suspended in 5% albumin containing 10 g/dl of hemoglobin; were employed as controls. At the completion of a 90% exchange transfusion, renal cortical and skeletal muscle tissue oxygen tensions, along with oxygen delivery and consumption, were sustained almost equally well with the HbV suspension compared to the washed rat red blood cell suspension, but declined significantly with the albumin suspension. The results indicate that the oxygen transporting capability of HbV was almost equivalent to that of rat red blood cells.

Differential effect of high extracellular Ca2+ on K+ and Cl- conductances in murine osteoclasts

Effects of the extracellular Ca2+ concentration ([Ca2+]o) on whole cell membrane currents were examined in mouse osteoclastic cells generated from bone marrow/stromal cell coculture. The major resting conductance in the presence of 1 mm Ca2+ was mediated by a Ba2+-sensitive, inwardly rectifying K+ (IRK) current. A rise in -Ca2+-o (5-40 mM) inhibited the IRK current and activated an 4'4'-diisothiocyano-2,2'-stilbenedisulfonate (DIDS)-sensitive, outwardly rectifying Cl- (ORCl) current. The activation of the ORCl current developed slowly and needed higher [Ca2+]o than that required to inhibit the IRK current. The inhibition of the IRK current consisted of two components, initial and subsequent late phases. The initial inhibition was not affected by intracellular application of guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) or guanosine 5'-O-(2-thiodiphosphate) (GDPbetaS). The late inhibition, however, was enhanced by GTPgammaS and attenuated by GDPbetaS, suggesting that GTP-binding proteins mediate this inhibition. The activation of the ORCl current was suppressed by pretreatment with pertussis toxin, but not potentiated by GTPgammaS. An increase in intracellular Ca2+ level neither reduced the IRK current nor activated the ORCl current. Staurosporine, an inhibitor for protein kinase C, did not modulate the [Ca2+]o-induced changes in the IRK and ORCl conductances. These results suggest that high [Ca2+]o had a dual action on the membrane conductance of osteoclasts, an inhibition of an IRK conductance and an activation of an ORCl conductance. The two conductances modulated by [Ca2+]o may be involved in different phases of bone resorption because they differed in Ca2+ sensitivity, temporal patterns of changes and regulatory mechanisms.

Identification of differentially expressed mRNAs during rat C6 glial cell differentiation by mRNA fingerprinting using arbitrarily primed PCR (RAP)

Differentiation of glial cells is controlled by a complex program of differential expressions of many genes. To identify differentially expressed genes that are involved in rat C6 glial cell differentiation induced by dibutyryl cyclic AMP and theophylline, mRNA fingerprinting using arbitrarily primed PCR (RAP) was used. Four cDNA fragments, that were differentially expressed during differentiation, were isolated. Sequence analysis revealed that one of them, abundantly expressed during differentiation, was homologous to a hamster calcium-dependent serine protease. Another one was highly similar to rabbit dystrobrevin and the other two clones were identical to rat triose phosphate isomerase and calnexin. The results obtained suggest that the expressions of particular genes were changed and that RAP is a useful method to identify genes which are differentially expressed during glial cell differentiation.

Effects of retinoids on the production of tumour necrosis factor-alpha and nitric oxide by lipopolysaccharide-stimulated rat Kupffer cells in vitro: evidence for participation of retinoid X receptor signalling pathway

Kupffer cells play important roles in the development of liver injury by producing cytokines and free radicals. In consequence inhibition of these inflammatory mediators will be one of the targets for treating liver diseases. Retinoids modulate a wide variety of functions of monocytes/macrophages. Cellular effects of retinoids are mediated by two families of nuclear receptors, retinoic acid receptors (RARs) and retinoid X receptors (RXRs). We examined the effects of several kinds of natural and synthetic retinoids on the production of tumour necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) by LPS-stimulated rat Kupffer cells in vitro. Of the various retinoids tested, 9-cis-retinoic acid (9-cis-RA) and Ro 13-6307 which are agonists of both RARs and RXRs, suppressed the production of TNF-alpha and NO in a concentration-dependent fashion, whereas three types of RAR-selective agonists, Ro 13-7410, Ro 40-6055 and Ro 19-0645 did not show any effect. Furthermore, the RAR alpha antagonist, Ro 41-5253, did not prevent the effects induced by 9-cis-RA. The results suggest that these effects of 9-cis RA and Ro 13-6307 were induced by the RXRs-dependent signalling pathway.

Increased circulating levels of insulin-like growth factor-I and decreased circulating levels of insulin-like growth factor binding protein-1 in postmenopausal women with endometrial cancer

In human endometrium insulin-like growth factor binding protein (IGFBP)-1 inhibits the mitogenic action of insulin-like growth factor (IGF)-I by inhibiting the binding of IGF-I to its receptor. Our purpose was to compare circulating levels of IGF-I and IGFBP-1 in women with and without endometrial cancer. We assessed circulating levels of IGF-I and IGFBP-1 and IGFBP-3 in 23 patients with endometrial cancer, 11 patients with uterine cervical cancer and 27 healthy control women. The mean circulating level of IGF-I decreased significantly following menopause but was not correlated with age in the control group. The body mass index was significantly higher in the endometrial cancer group than in the control group. Analysis of covariance showed that even after the data were adjusted to eliminate the influence of the body mass index, the circulating IGF-I concentration was higher in postmenopausal endometrial cancer patients than in postmenopausal control subjects. The mean circulating level of IGFBP-1 was significantly lower in postmenopausal cancer patients than in postmenopausal control subjects. There were no significant differences in the serum levels of IGF-I and IGFBP-1 in the patients with cervical cancer and the control group. In conclusion, an increased circulating concentration of IGF-I and a decreased circulating concentration of IGFBP-1 are associated with endometrial cancer especially in postmenopausal women.

V-onc product expression in early phase post perinatal retrovirus infection predictive of malignancy of induced lesions

Sixteen sarcomas developed in rats within 40 days post perinatal infection with feline sarcoma virus of Snyder-Theilen strain were examined to elucidate the association of the viral oncogene product (P85) expression with malignancy of developed sarcomas. Of these, 6 grew up to index-finger-tip-size, consisted of spindle shaped sarcoma cells and had no metastasis (group A), and 10 grew over thumb-tip-size, consisted of polygonal shaped sarcoma cells and had frequent metastasis (group B). One group A tumor and 8 group B tumors expressed P85. The v-onc product expression was thus found to be predictive of malignancy of induced tumors.

A diabetic case with hemoglobin J-Meerut and low HbA1C levels

A diabetic patient with hemoglobin (Hb) J-Meerut and low HbA1C levels is reported. An automatic glycohemoglobin analyzer used for the determination of HbA1C revealed an abnormal peak of the peripheral blood obtained from a Japanese female with diabetes. She showed a lower HbA1C level (3.7%) than expected from her fasting plasma glucose (172 mg/dl). High performance liquid chromatography and isoelectric focusing indicated that her abnormal hemoglobin was Hb J-Meerut [alpha 120(H3)Ala-->Glu] and it accounted for 28.3% of the total hemoglobin. Abnormal hemoglobinemia should be considered when a major discrepancy between the levels of HbA1C and fasting plasma glucose is observed.

Convulsions in hemodialysis (HD) patients with elevated polymorphonuclear leukocyte elastase (PMNE) levels

Eight hemodialysis (HD) patients with convulsions of unknown cause were monitored for serum levels of uremic toxins such as methylguanidine(MG), and polymorphonuclear leukocyte elastase (PMNE). Twenty HD patients without convulsions served as controls. In the convulsion group, MG and PMNE were high. In 2 patients, convulsions subsided after daily hemodiafiltration (HDF). Although PMNE was thought to be a mediator of injury in the present series, no significant correlation was found between PMNE and either neutrophil numbers or endotoxin levels. PMNE may indicate the over production of cytokines not associated with serious infection or septicemia. In patients with renal failure and complications of unknown cause, intensified dialysis therapy such as frequent HDF may be useful when combined with treatment of the underlying disease producing the toxins. PMNE measurement is useful in assessing the uremia caused by high cytokine levels and, together with methylguanidin (MG) serum levels, can indicate the severity of the convulsion.

Human immunodeficiency virus type 1 Vpu modifies viral cytopathic effect through augmented virus release

We characterized two human immunodeficiency virus type 1 (HIV-1) strains, HIVMCK and HIV213, which have different cytopathic effects in infected cells. HIV213 was highly cytopathic, whereas HIVMCK was not. Biological analyses of chimeric viruses from the cloned infectious DNAs of HIVMCK and HIV213 showed that the Vpu region was responsible for the differing cytopathicity of these viruses. Although HIVMCK expressed Vpu protein, HIV213 did not because of a mutation at the start codon for Vpu. The amounts of envelope glycoprotein and virus particles associated with the cell surface were significantly increased on cells infected with Vpu-deficient viruses compared with Vpu-positive viruses. These data suggest that the highly cytopathic effects of HIV213 (Vpu-deficient) are due to an accumulation of envelope glycoprotein at the infected-cell surface, which would be caused by the retention of progeny virions in the absence of Vpu-facilitated virion release.