bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of desmin-positive rat liver sinusoidal cells
Authors: Tsutsumi Mikihiro , Takada Akira , Takase Shujiro
Published: March 2007

Hepatic sinusoidal lining cells were isolated from mature male rats (12 months old) and cultured in order to clarify the characteristics of the Ito cells (fat-storing cells). Desmin staining was used as a marker in the isolation of the Ito cells, and a highly purified desmin-positive cell fraction was obtained. Less than 10% of the desmin-positive cells were positive for vitamin A auto-fluorescence. However, the number of vitamin A-positive cells increased with vitamin A treatment, and they extended to over half of the desmin-positive cells by the first week of vitamin A treatment. The cultured Ito cells were positive for both desmin and vimentin stainings. On the other hand, Kupffer and endothelial cells were positive only with vimentin staining. Ito cells lost their fat droplets after repeated subculturing. The electron microscopic features of the Ito cells became similar to those of myofibroblasts, except for the absence of dense bodies, indicating that the Ito cells may have possibly transformed into myofibroblasts. Collagen fibers were occasionally found in the extracellular space. These results indicate that Ito cells retain both their myogenic and fibrogenic properties, and that lipocytes or myofibroblasts may be desmin-positive cells which maintain specific functions. Furthermore, staining of the intermediate filaments is useful in the identification of Ito cells, and a highly purified Ito cell fraction can be easily obtained using desmin staining as a marker.
Anticalmodulin autoantibody in liver diseases: A new antibody against a cytoskeleton-related protein
Authors: Ikeda Yusei , Toda Gotaro , Hashimoto Naoaki , Aotsuka Shin-Ichi , Yokohari Ryuichi , Maruyama Toshiyuki , Oka Hiroshi
Published: March 2007

An ELISA has been developed for detection of auto-antibodiees against calmodulin. There was a significantly increased frequency (63.1%) of autoantibodies against calmodulin in 103 patients with chronic liver diseases as compared to that (30%) of patients with systemic lupus erythematosus and to that (6.9%) of normal subjects (p < 0.01). IgG autoantibodies against calmodulin were detected in the patients with acute hepatitis (37.9%), chronic liver disease (45.6%) and also in the patients with systemic lupus erythematosus (30%). IgM autoantibodies against calmodulin were frequently found in patients with liver cirrhosis (52.2%), primary biliary cirrhosis (50%) and autoimmune chronic active hepatitis (38.7%), but rarely in patients with acute hepatitis (13.8%), chronic persistent hepatitis (9.5%) and systemic lupus erythematosus (0%). IgA autoantibodies against calmodulin were frequently found in liver cirrhosis (33.3%), primary biliary cirrhosis (452.9%) and autoimmune chronic active hepatitis (53.6%), but rarely in chronic persistent hepatitis (15.8%), chronic active hepatitis (14.3%) and systemic lupus erythematosus (0%).

The occurrences of autoantibodies against calmodulin correlated neither with those of antismooth muscle antibody, antinculear antibody and antimitochondrial antibody, nor with serum IgG concentrations. Autoantibodies against calmodulin did not cross-react with troponin, myosin light chain, calf thymus DNA and actin. The titer of autoantibodies against calmodulin was decreased by absorption of serum with calmodulin and the liver plasma membrane fraction. The immunoblotting experiment revealed the bidning of autoantibodies against calmodulin to calmodulin. IgG fraction from a patient with autoimmune chronic active hepatitis inhibited the activation of phosphodiesterase by calmodulin. These results provide us with valuable information to elucidate the immunological abnormality in liver diseases.
Interaction of natural and synthetic albumin polymers with hepatocytes
Authors: Wright Teresa L. , Lysenko Nina , Ockner Robert K. , Weisiger Richard A.
Published: March 2007

The hepatitis B virus binds avidly to albumin polymers which in turn may mediate the initial binding of viral particles to the liver cell. However, the interaction of albumin polymers with the liver remains poorly characterized, and the possibility that hepatic binding reflects an artifact of polymerization with glutaraldehyde has not been excluded. We therefore characterized the binding of 125I-labeled natural and synthetic albumin polymers to suspensions of rat hepatocytes.

Saturable binding was demonstrated for all preparations of monomeric and polymeric albumin studied. Glutaraldehyde-polymerized albumin (mean polymerization number = 15) bound much more avidly than naturally occurring albumin polymers (mostly dimers and trimers) or monomeric albumin. Competition between monomer and synthetic polymer was not observed. Reduction of free aldehyde groups on the synthetic polymer decreased nonsaturable binding without affecting saturable binding. Autoradiography confirmed binding of polyalbumin to hepatic parenchymal cells. Glutaraldehyde-polymerized ovalbumin, a protein unrelated to serum albumin, also bound hepatocytes saturably.

We conclude that hepatic binding of synthetic albumin polymers is not due to residual aldehyde groups on the polymer and is much more avid than for natural polymer. This difference may reflect the higher degree of polymerization or chemical modification of the synthetic polymer. The hepatic binding sites for synthetic polymer appear distinct from those previously described for monomeric albumin and may not be specific for albumin.
Long-term follow-up study of asymptomatic hbsag-positive voluntary blood donors in austria: A clinical and histologic evaluation of 242 cases
Authors: Dragosics Brigitte , Ferenci Peter , Hitchman Eva , Denk Helmut
Published: March 2007

Two hundred forty-two voluntary blood donors, referred after detection of HBsAg positivity, underwent clinical evaluation and liver biopsy and were prospectively followed for an average of 3.5 years. At initial testing, 65% of HBsAg carriers had normal laboratory findings; during follow-up, 26% of these carriers developed abnormal test results, at least transiently. Liver histology was normal in 31.4%, revealed nonaggressive liver disease in 63.6% and chronic active hepatitis or cirrhosis in 5%, only. All except one case of chronic active hepatitis or cirrhosis were associated with abnormal blood biochemical tests. Sequential liver biopsies obtained in 56 HBsAg carriers after a minimal interval of 4 years showed mitigation of inflammatory changes in 5.4% and developing chronic active hepatitis in three cases (5.4%). One carrier died of primary hepatocellular carcinoma.

Upon follow-up, HBsAg persisted in 98%. Anti-HBe was found in 90% of all carriers already at the initial testing. HBeAg positivity (7.5%) was associated with chronic active hepatitis as well as nonaggressive liver disease; clearance of HBeAg occurred in 40% after 2 to 8 years. Because of the subclinical progression of liver disease and the increased risk for developing primary hepatocellular carcinoma in asymptomatic HBsAg carriers, routine blood testing, including α-fetoprotein screening, as well as abdominal ultrasound surveillance are indicated. Liver biopsy, however, should be restricted to carriers with abnormal biochemical findings.
Stimulatory effects of ethanol on amino acid transport by rat fetal hepatocytes
Authors: Heitman David W. , Frosto Teri A. , Schenker Steven , Henderson George I.
Published: March 2007

Previous studies have indicated that acute, and especially chronic, maternal ethanol consumption can depress placental uptake of various amino acids. Since the fetal cell itself represents a second barrier to nutrients, one which may be altered by ethanol exposure, the effects of ethanol on amino acid net uptake by rat fetal hepatocytes was addressed. The present study determined that ethanol stimulated amino acid net uptake by fetal hepatocytes grown in monolayer culture. Fetal liver cells were grown in custom Williams' E medium (without L-arginine and with L-ornithine) and exposed to epidermal growth factor (0, 1, 2 or 5 ng per ml) and ethanol (1.7 ± 0.1 or 3.9 ± 0.2 mg per ml). Addition of ethanol (3.9 mg per ml) to the culture medium completely blocked measurable cell replication during a 48-hr exposure period. Fetal hepatocytes exposed to ethanol accrued both protein and water in a parallel fashion, both in excess of that by control cells. Ethanol (1.7 and 3.9 mg per ml) for 48 hr stimulated α-aminoisobutyric acid net uptake by fetal hepatocytes (p < 0.05). Efflux was not affected (p < 0.05). The onset of this significant stimulation of net uptake was progressive and required in excess of 6 hr of contact with ethanol. This ethanol stimulation of α-aminoisobutyric acid net uptake persisted for at least 24 hr following ethanol withdrawal. The component(s) of α-aminoisobutyric acid net uptake stimulated by ethanol was independent of extracellular Na+. In addition, ethanol stimulated net uptake of two other marker amino acids, methyl-α-aminoisobutyric acid and cycloleucine (54 and 128%, respectively, p < 0.05). In summary, these data suggest: (i) ethanol can stimulate the net uptake of amino acids by fetal hepatocytes while not affecting efflux; (ii) this effect requires an exposure period in excess of 6 hr and is not rapidly reversible, and (iv) ethanol exposure (3.9 mg per ml) totally prevents fetal hepatocyte replication and causes a 3- to 4-fold increase (accumulation) in cellular protein and water.
Depression of peripheral blood monocyte aryl hydrocarbon hydroxylase activity in patients with liver disease: Possible involvement of macrophage factors
Authors: Peterson Theresa C. , Williams Noel C.
Published: March 2007

Aryl hydrocarbon hydroxylase activity was detectable in cultured macrophage monolayers of peripheral blood monocyte origin. Peripheral blood monocytes were isolated from patients with biopsy-confirmed liver disease and healthy volunteers. Macrophage monolayers were prepared and incubated at 37°C. After 24 hr, the aryl hydrocarbon hydroxylase activity and cellular protein concentration were assayed on cell homogenates. The monocyte aryl hydrocarbon hydroxylase activity in cultured macrophages from normal volunteers was 1.23 ± 0.16 (n = 19). The aryl hydrocarbon hydroxylase activity in macrophage cultures from patients with biopsy-confirmed liver disease was 0.48 ± 0.05 (n = 20). This represents a significant (61%) decrease in monocyte aryl hydrocarbon hydroxylase compared to controls. The 20 patients have established cirrhosis or early stage liver disease. The established cirrhosis group includes α1-antitrypsin deficiency-associated cirrhosis; primary biliary cirrhosis; alcoholic (Laennec's) cirrhosis; cryptogenic cirrhosis, and hemochromatosis. Early stage liver disease is attributed to methotrexate (Stage III), early stage primary biliary cirrhosis and α1-antitrypsin deficiency. Our results indicate that the depression in monocyte aryl hydrocarbon hydroxylase activity is greater in patients with established cirrhosis than early stage liver disease.

Our results further suggest that cultured monocytes from patients with liver disease spontaneously release soluble factors into the culture medium. Incubation of this medium, containing macrophage factors, with isolated hepatocytes significantly depress hepatocyte aryl hydrocarbon hydroxylase activity compared to medium obtained from cultures of monocytes from normal volunteers.

We propose that cultured monocyte aryl hydrocarbon hydroxylase activity mimics the hepatic enzyme and reflects the status of the hepatic enzyme in severe liver disease. Consequently, monocyte aryl hydrocarbon hydroxylase activity may be a useful noninvasive measure of hepatic enzyme function.
Overnight salivary caffeine clearance: A liver function test suitable for routine use
Authors: Jost Gerhard , Wahlländer Axel , Mandach Ursula Von , Preisig Rudolf
Published: March 2007

The feasibility of measuring caffeine clearance from saliva (SCI) was assessed in ambulatory patients with liver disease and in a control group, and the results were compared with quantitative liver function tests. For this purpose, the subjects were given 280 mg caffeine p.o. in decaffeinated coffee powder between noon and 4 p.m., and caffeine concentrations were measured in saliva (using an enzyme immunoassay) before bedtime and upon arising. In the cirrhotics (n = 29), SCI was 0.58 ± S.D. 0.45 ml per min × kg, thus being reduced to approximately one-third of drug-free, nonsmoking controls (1.53 ± 0.46, n = 18); although patients with non-cirrhotic liver disease showed intermediate values (0.95 ± 0.47), their reduction in SCI was significant (p < 0.001). SCI was correlated with indocyanine green fractional clearance, galactose elimination capacity and aminopyrine breath test; however, the closest relationship (Rs = 0.80) was observed with the aminopyrine breath test. It is suggested that the measurement of SCI represents a noninvasive and innocuous procedure for quantifying hepatic microsomal function, and is suitable for routine use. Since a.m. saliva concentrations of caffeine are highly correlated (Rs = −0.94) with SCl, further simplification of the test to a single-point measurement appears possible.
Toxic effects of the photoproducts of chlorpromazine on cultured hepatocytes
Authors: Castell José V. , Gómez-Lechón José M. A. , Miranda Miguel A. , Morera Isabel M.
Published: March 2007

The photodegradation of chlorpromazine, a drug frequently used in psychotherapy, was examined under different sets of experimental conditions. A primary culture of rat hepatocytes was used to evaluate the possible hepatotoxicity of the chlorpromazine photoproducts, keeping in mind the following criteria: leakage of cytosolic enzymes; attachment index to culture plates, and albumin synthesis. Cells exposed to concentrations greater than 10−4
M of the photomixtures showed extensive leakage of GOT and GPT into the culture medium and, at the same time, the cell attachment was seriously impaired. A concentration of 10−7
M of the photoproducts proved capable of inhibiting the synthesis of albumin (20%). Photoproducts obtained after aerobic irradiations were as toxic for hepatocytes as those found in anaerobic conditions. The implications of our results in connection with the relevance of oxygen-dependent photoreactions of chlorpromazine to its phototoxicity, and the possible appearance of hepatic alterations in patients treated with the drug after exposure to the sunlight, are discussed.
Liver cell dysplasia: What is its significance?
Authors: Anthony Peter B.
Published: March 2007

Liver cell dysplasia (LCD) was investigated for hepatitis B virus (HBV) markers, alpha-fetoprotein (AFP) and ferritin by serologic and immuno-histochemical methods in 101 patients with cirrhosis. LCD was found in 30 cases (29.7%), with the highest incidence in cases of posthepatitic cirrhosis (67%). In the group of dysplastic cirrhosis (DC) 46.6% of the patients had active HBV infection (hepatitis B surface antigen [HBsAg] serum positivity) compared with 7% of the patients with nondysplastic cirrhosis (NDC) (P < 0.01). The mean serum AFP concentration was significantly raised in the DC group compared with that in the NDC group (P < 0.05). In seven patients with LCD at the initial biopsy, the histologic follow-up showed the persistence of LCD in all cases, and the development of hepatocellular carcinoma (HCC) in three cases. In serologic HBsAg-positive cases, dysplastic cells, at variance with the surrounding liver parenchyma, were almost always negative for tissue HBsAg, and always negative for tissue hepatitis B core antigens (HBcAg). AFP was never detected in either normal or dysplastic cells. Ferritin was found in all cases, but dysplastic foci displayed a lesser amount of this protein. These serologic and immunohistochemical data strongly suggest a preneoplastic significance of LCD. The importance of monitoring cirrhotic patients with LCD and particularly those with HBV infection and/or increased AFP levels with more aggressive follow-up is also stressed.

An assessment was made of the frequency of liver cell dysplasia and the mean age of each group in 56 normal, 13 cirrhotic, and 50 hepatocellular carcinoma (HCC) patients, 40 with cirrhosis, from southern Africa. Dysplasia increased from 7.1% in normal subjects to 38.5% in cirrhotic, 40% in non-cirrhotic HCC, and 52.5% in cirrhotic HCC patients, three statistically similar frequencies. Average patient ages were as follows: patients with normal livers, 37.3 years; with cirrhosis, 42.4 years; with noncirrhotic HCC, 36.5 years; and with cirrhotic HCC, 34 years, the mean age with dysplasia being lower than that of the whole group. With no increase in frequency of dysplasia from cirrhosis to HCC with cirrhosis, with a similar high frequency in HCC without cirrhosis, and with a mean age of all HCC patients 8 years less than that of cirrhotics and 3 years less than normals, chronologic evolutionary progression from cirrhosis to dysplasia to HCC in southern Africa cannot be demonstrated.
Encapsulated hepatocellular carcinoma in the absence of cirrhosis: A favorable prognosis
Authors: Schaffner Fenton
Published: March 2007

Clinicopathological features were studied in 41 patients with histology-proven hepatocellular carcinoma without cirrhosis. Of these, 13 (31.7%) were positive for hepatitis B virus surface antigen (HBsAg) and 28 were negative. Twenty-six of 28 (92.9%) HBsAg negative cases had anticore antibody (anti-HBc) of low titres. The age of patients at the time of diagnosis of hepatocellular carcinoma was significantly younger in the HBsAg positive cases compared with the negative. The initial diagnostic clue was either abdominal mass or abdominal pain in 18 (43.9%) patients. However, the number of patients in whom hepatocellular carcinoma was detected by imaging in the absence of such clinical signs has increased recently. The tumour was encapsulated in 31 cases (75.6%) and most solitary encapsulated tumours were growing expansively. Tumours were resectable in 29 (70.7%) cases, and the prognosis of resected cases was much better than that of 12 non-operated cases. Twenty-one out of 29 (72.4%) resected tumours were solitary and encapsulated. However, recurrence of tumour occurred in 12 out of 28 (42.9%) cases, and it was within 2 years of resection in 11 cases. These observations and data seem to indicate that early detection and resection of tumour is very important in management, but tumour recurrence is inevitable in a considerable proportion of the patients with non-cirrhotic hepatocellular carcinoma.
Bile acid transport: Lessons from the intestine
Authors: Moseley Richard H.
Published: March 2007

The transport of bile acid was studied in basolateral membrane vesicles isolated from rat small intestine. Taurocholate transport into an osmotically reactive intravesicular space was Na+ independent. The uptake of taurocholate in jejunal and ileal vesicles preloaded with sulfate was stimulated with respect to uptake in unpreloaded vesicles. Glycocholate inhibited the transstimulation of taurocholate uptake by sulfate. Sulfate and taurocholate uptake in ileal vesicles preloaded with bicarbonate was stimulated with respect to uptake in unpreloaded vesicles. Taurocholate inhibited the transstimulation of sulfate uptake by bicarbonate. When ileal vesicles were loaded with p-aminohippurate, an early transstimulation of taurocholate was found that exceeded equilibrium uptake, was insensitive to a K+ diffusion potential, and was cis-inhibited by taurocholate, glycocholate, pyruvate, p-aminohippurate, probenecid, chloride, sulfate, and bicarbonate. These data indicate the presence of an anion exchanger in intestinal basolateral membrane vesicles that may be involved in the exit of bile acids from the enterocyte.
Le Veen vs. Denver peritoneovenous shunts: Inadequate numbers or technique?
Authors: Blendis Laurence M. , Lund Robert H.
Published: March 2007

Peritoneovenous shunts (PVSs) have provided salutary effects on medically recalcitrant ascites, functional renal impairment, nutritional derangements, ventilatory embarrassment, and locomotion potential in patients with cirrhosis. While the LeVeen (LPVS) and Denver (DPVS) PVSs are most frequently implanted in such patients, postoperative complications of bleeding gastroesophageal varices, sepsis, and shunt occlusion occur with notable frequency. Addressing primarily the complication of PVS occlusion, a randomized prospective trial of LPVSs and DPVSs was conducted in cirrhotic patients with refractory ascites. From July 1, 1982 to July 1, 1984, 26 initial PVSs were implanted for hepatic-related intractable ascites. Twenty-two patients were eligible for randomization (cirrhosis, sterile ascites, initial PVS, total bilirubin level ≦6.0 mg/dL, prothrombin time ≦5-s prolongation, serum creatinine level ≦2.0 mg/dL [creatinine clearance rate ≧20 mL/min], absence of recent [<30 days] bleeding gastroesophageal varices, or absent spontaneous encephalopathy). Twelve LPVSs and ten DPVSs were implanted; however, one patient with a DPVS was found to have hepatic polycystic disease and was excluded from analysis. All patients were followed up until death or January 1, 1985. The PVS patency determinations included contrast shuntography, technetium Tc 99m albumin scintigraphy, sequential manual compression (DPVS), and operative or autopsy observation. Using the Kaplan-Meier actuarial analysis, the LPVS patency proved to be highly superior to that of the DPVS, while survival was not significantly different. As LPVS and DPVS complications other than patency are comparable, the LPVS is preferred for its superior patency in cirrhotic patients with intractable ascites.
Interrelationship between splenic and superior mesenteric venous circulation manifested by transient splenic arterial occlusion using a balloon catheter
Authors: Nishida Osamu , Moriyasu Fuminori , Nakamura Takefumi , Ban Nobuyuki , Miura Kensuke , Sakai Masahiko , Uchino Haruto , Miyake Takeo
Published: March 2007

We examined the hemodynamic changes induced by transient splenic arterial occlusion using a balloon catheter to investigate the hemodynamic effect of transcatheter splenic arterial embolization—a procedure that has been used since its introduction in 1973 as therapy for hypersplenism and more recently for portal hypertension. The blood flow volume was measured in 20 patients with liver disease using an ultrasonic duplex system (Toshiba SAL50A/SDL-01A). The portal venous pressure was also measured via a 3F catheter using a transducer. The catheter was placed in position by substituting it for a 25-gauge needle that had been inserted into the portal vein under ultrasonic guidance percutaneously and transhepatically.

Splenic arterial occlusion caused a drop in splenic venous blood flow from 708 ± 487 to 241 ± 155 ml per min, in portal venous blood flow from 993 ± 439 to 807 ± 419 ml per min and in portal venous pressure from 17.4 ± 7.2 to 14.4 ± 6.1 mm Hg. The latter two reductions were less than expected from the decrease in the splenic venous blood flow volume. This phenomenon was caused by an increase in the mesenteric venous blood flow from 475 ± 126 to 630 ± 270 mm per min.

This increase may be due to a compensatory mechanism under the control of a regulatory loop in the liver or portal vein, and there seems to be a relationship between splenic and intestinal circulation in portal hypertension that maintains hepatic circulation.
Anti-liver-kidney microsome antibody is a marker for the rat hepatocyte endoplasmic reticulum
Authors: De Lemos-Chiarandini Carmen , Alvarez Fernando , Bernard Olivier , Homberg Jean Claude , Kreibich Gert
Published: March 2007

Human sera, containing anti-liver-kidney microsome antibody as demonstrated by indirect immunofluorescence, were obtained from a subgroup of young patients with autoimmune chronic hepatitis. The anti-liver-kidney microsome antibody-positive sera were used to study the localization of the liver-kidney microsome antigen in hepatocytes. Immunoblot analysis of microsomal subfractions, lysosomal membranes, plasma membranes, mitochondria and purified ribosomes obtained from rat liver demonstrated that this antibody recognizes a protein of 50 kD present only in endoplasmic reticulum membranes. Immunogold labeling of ultrathin frozen sections and immunoperoxidase staining of 11 to 15 μm cryostat sections were used to detect the liver-kidney microsome antigen in rat liver tissue. The anti-liver-kidney microsome antibody binds to antigenic domains on the cytoplasmic face of smooth and rough endoplasmic reticulum membranes of hepatocytes. No labeling was observed of the Golgi apparatus, peroxi-somes, mitochondria, lysosomes, nuclei or plasma membranes. Not only was the antigen recognized by the anti-liver-kidney microsome antibody specific for endoplasmic reticulum membranes, but it was also specific for the endoplasmic reticulum of hepatocytes only, since no labeling was observed in any organelle of Kupffer or endothelial cells. Therefore, the anti-liver-kidney microsome antibody can be considered as a marker for endoplasmic reticulum in rat hepatocytes.
Role of acetaldehyde in the ethanol-induced impairment of hepatic glycoprotein secretion in the rat In vivo
Authors: Volentine Gary D. , Ogden Kathleen A. , Kortje David K. , Tuma Dean J. , Sorrell Michael F.
Published: March 2007

Ethanol administration inhibits hepatic protein and glycoprotein secretion. Previous studies have shown that the metabolism of ethanol is required for this effect. Experiments were designed to determine whether acetaldehyde, the first metabolite of ethanol oxidation, mediated the ethanol-induced secretory defect in rats with normal and stimulated (inflammation-induced) rates of hepatic protein secretion. This study used cyanamide, an aldehyde dehydrogenase inhibitor, to correlate enhanced acetaldehyde levels with an increased ethanol-induced inhibition of hepatic protein secretion. Inflammation was induced by turpentine 24 hr prior to cyanamide (5 mg per kg body weight) or saline pretreatment. Nonfasted rats were intragastrically gavaged with ethanol (4 to 6 gm per kg body weight) or isocaloric glucose 1 hr following pretreatment. [3H]Fucose and/or [14C]leucine were injected intravenously 2 hr following intubation. With elevated levels of acetaldehyde, the ethanol-induced impairment of secretion of labeled proteins and their parallel retention in the liver were markedly potentiated.During inflammation, this inhibition of secretion by ethanol was maintained and further increased with cyanamide pretreatment. These results indicate that the ethanol-induced impairment of hepatic glycoprotein secretion is mediated by acetaldehyde in both normal and inflammation-stimulated animals.
Modulation of the immunological response to hepatitis b virus by antibodies
Authors: Celis Esteban , Abraham Katalin G. , Miller Richard W.
Published: March 2007

Antibodies to HBsAg of IgG class enhanced the helper activity of a human T cell clone to promote the in vitro synthesis of immunoglobulins by autologous B lymphocytes. Using two different assay systems, the effect of antigen-specific antibodies on the helper function of a HBsAg-reactive T cell clone was studied. The monoclonal antibody to HBsAg A5C3 (IgG) increased significantly the T cell-dependent production of immunoglobulins by Staphyloccocus aureus-stimulated autologous B lymphocytes. Furthermore, the results obtained with a different type of assay showed that A5C3 also increased the synthesis of antibody to HBsAg by the autologous B cells in the presence of HBsAg and the helper T cell clone. On the other hand, when the monoclonal antibody to HBsAg of IgM class, H5D3 or the F(ab′)2 fragment of A5C3 were tested, no significant enhancement of the helper activity of the T cell clone was observed. Experiments performed in mice showed that the in vivo antibody to HBsAg response to low concentrations of HBsAg was significantly enhanced by mixing this antigen with monoclonal antibody to HBsAg of IgG class. No effect was observed when a monoclonal antibody to HBsAg of IgM class was used to prepare the immune-complexed immunogen. The results presented here suggest that antibodies play a critical role in their own production through regulating the activity of helper T cells. This phenomenon might contribute to the increased antibody synthesis of in vivo secondary immune responses and could be of use in designing more efficient vaccine programs in man.
Surrogate tests and the risk of posttransfusion hepatitis; their time has come
Authors: Aach Richard D.
Published: March 2007

A total of 481 recipients of blood transfusions who had received 6,295 units of blood were followed for 6-9 months in order to evaluate the relationship between posttransfusion hepatitis (PTH) and transfusion of blood that is positive for antibody to hepatitis B core antigen (anti-HBc). The incidence of non-A, non-B PTH (NANB-PTH) was 11.9% among the 193 recipients who received one or more units of anti-HBc-positive blood compared to only 3.2% of the 288 recipients of only anti-HBc-negative blood (p < 0.001). There was, however, no statistically significant difference in the prevalence of hepatitis B virus or hepatitis B serological response following transfusion of anti-HBc-positive blood compared to anti-HBc negative blood. The relationship of NANB-PTH following receipt of anti-HBc-positive blood and/or blood with an elevated ALT level was studied in a subset of 230 recipients and their 1,549 donors. Donor anti-HBc appeared to be more closely associated with an increased rate of NANB-PTH than an elevated donor ALT level, or with the volume of blood transfused. Donor blood that was anti-HBc-positive and blood with increased ALT activity behaved as independent variables with respect to the development of NANB-PTH. Although only 15% of the units that were anti-HBc-positive were associated with NANB-PTH, calculation of maxi-mal correlated efficacy predicted that exclusion of the 4% of the units that were anti-HBc-positive might have prevented 43% of the cases of NANB-PTH. The authors conclude that screening donors with surrogate tests should be seriously considered because of the serious complications of NANB-PTH.
The in vitro production of Dane-like particles: Is it live or memorex?
Authors: Farraye Francis A. , Zeldis Jerome B.
Published: March 2007

Closed-circular HBV DNA was introduced into cells of the established human hepatoma culture HepG2. The culture medium of one of 40 single-cell clones contained HBV surface antigen (HBsAg), core-related antigens (HBc/eAg), and HBV DNA sequences. HBV DNA and DNA polymerase activity were detected in particles resembling both nucleocapsids and complete virions (Dane particles). Intracellular integrated and extrachromosomal HBV DNA sequences were detected. Relaxed-circular and single-stranded forms of viral DNA were identified as likely replicative intermediates of the HBV genome. In conclusion, in vitro production of Dane-like particles by transformed human hepatocytes has been achieved. This model should be valuable as a cell culture system for studying virus replication and virus-host cells interactions.
Immunohistochemical distribution of renal prostaglandin endoperoxide synthase and prostacyclin synthase: Diminished endoperoxide synthase in the hepatorenal syndrome
Authors: Govindarajan Sugantha , Nast Cynthia C. , Smith William L. , Koyle Martin A. , Daskalopoulos George , Zipser Robert D.
Published: March 2007

To evaluate possible causes of the diminished prostaglandin production in advanced hepatorenal syndrome, prostaglandin endoperoxide synthase and prostacyclin synthase were localized and semiquantitated by immunofluorescence in postmortem, biopsy and nephrectomy renal tissues. In normal kidneys, antiprostacyclin synthase serum caused intense staining in peritubular capillaries, in the adjacent renal interstitial cells and in glomerular mesangial regions. Antiprostaglandin endoperoxide synthase serum caused staining of collecting duct epithelial cells, cells of the thin ascending limb and possibly glomerular mesangial cells. Prostacyclin synthase-positive staining was graded 5+ (scale of 0+ to 5+) in all kidney samples. Medullary collecting tubule prostaglandin endoperoxide synthase-positive staining was graded 4+ or 5+ in kidney samples from patients with acute tubular necrosis or acute tubulointerstitial nephritis and from patients with liver failure without the hepatorenal syndrome. However, prostaglandin endoperoxide synthase-positive staining was markedly diminished or absent (average 1+) in patients with the hepatorenal syndrome. These data suggest that loss of the medullary prostaglandin endoperoxide synthase is the cause of diminished urinary prostaglandin E2 excretion in the hepatorenal syndrome.
Rat liver endothelial cells have a greater capacity than kupffer cells to endocytose N -acetylglucosamine- and mannose-terminated glycoproteins
Authors: Praaning-Van Dalen Danielle P. , De Leeuw Margreet A. , Brouwer A. , Knook Dick L.
Published: March 2007

The capacity of rat liver Kupffer and endothelial cells to endocytose glycoproteins with N-acetylglucosamine-or mannose-terminated oligosaccharide chains was studied. For this purpose, agalactoorosomucoid, ahexo-saminoorosomucoid and horseradish peroxidase were used as ligands. A reliable determination of the amount of ligand endocytosed in vivo or in vitro was made possible by using the recently developed cold pronase method for the isolation and purification of Kupffer and endothelial cells. Both cell types participated in the uptake of the ligands in vivo as well as in vitro, but their endocytic capacity was several times greater in vivo than in vitro. Under both conditions, endothelial cells possessed a greater capacity to endocytose the ligands than did Kupffer cells. Since the total number of endothelial cells in the liver is at least twice the number of Kupffer cells, the contribution of endothelial cells to the liver uptake of N-acetylglucosamine-terminated glycoproteins in vivo was estimated to be 3 to 7 times higher than that of the Kupffer cells. In vitro experiments showed that the uptake of the glycoproteins followed saturation kinetics and was strongly inhibited at 4±C and in the presence of mannan. Ultrastructural investigations revealed that horseradish peroxidase was taken up by all Kupffer and endothelial cells. These results emphasize the important role liver endothelial cells play in the clearance of specific glycoproteins from the circulation.
Identification and characterization of liver nonparenchymal cells by flow cytometry
Authors: Doolittle Mark , Bohman Roger , Durstenfeld Andres , Cascarano Joseph
Published: March 2007

Our objective was to correlate biochemical or functional properties that could be measured by fluorescence to individual nonparenchymal cell types by the simultaneous detection of forward angle light scatter and fluorescence. Cells were released from liver following selective digestion of hepatocytes by Pronase perfusion. To fractionate the cells according to size, isolates were subjected to unit gravity sedimentation on a 1 to 5% sucrose gradient. Flow cytometry was used to analyze the resulting fractions as well as the original unfractionated cells. This reaffirmed that forward angle light scatter is linearly related to the sedimentation velocity (size) of the cells and that it can be used to assess cell sizes in an unfractionated population. Endocytosis of fluorescently tagged particulates was studied by injecting either fluorescein isothiocyanate-tagged colloidal albumin or Coumarin-tagged latex beads (0.57 μm diameter) prior to Pronase perfusion. Beads were found only in the largest cells (Kupffer cells). Since endothelial cells could endocytose only colloidal albumin, they were readily differentiated from nonendocytosing, nonsinusoidal cells (“lymphocytes”). Staining cell protein with fluorescein isothiocyanate made possible the determination of relative protein content per cell (“lymphocyte”: endothelial:Kupffer cell was 0.57:1.0:2.0). To determine relative esterase activities, mixed cell isolates were incubated in fluorescein diacetate (“lymphocyte”: endothelial:Kupffer cells was 0.13:1.0:2.4). Uptake of rhodamine 123 was used to assess mitochondrial function (“lymphocyte”:endothelial:Kupffer cells was 0.45:1.0:14.6). Mitochondrial volume per cell is known to be 1:2 for endothelial:Kupffer cells. Therefore, the large difference in rhodamine uptake is not related to volume.
Experimental transmission of duck hepatitis B virus to pekin ducks and to domestic geese
Authors: Marion Patricia L. , Cullen John M. , Azcárraga Roberto R. , Van Davelaar Mary Jo , Robinson William S.
Published: March 2007

We investigated experimental transmission of duck hepatitis B virus to its original host, the domestic Pekin duck, and to three other avian species. Intramuscular injection of a standard inoculum of duck hepatitis B virus into 2- to 5-day-old Pekin ducklings hatched from a duck hepatitis B virus-free flock resulted in viremia in 100% of 107 animals, indicating that duck hepatitis B virus infection of young progeny of a defined duck hepatitis B virus-free flock occurs reproducibly. When the same inoculum was injected into chicks and Muscovy ducklings of the same age, no evidence of viral infection was detectable. In contrast, hatchlings of two domestic breeds of geese were readily infected by duck hepatitis B virus, developing viremia at a slower rate than Pekin ducklings, but a higher average titer of viremia 4 weeks or more after injection. Neither the pattern of restriction enzyme sites in the viral DNA nor the susceptibility of ducklings to the virus were detectably altered after passage in geese. As in duck hepatitis B virus-infected young ducklings, most of the experimentally infected goslings appeared to be persistently infected and those eventually laying eggs transmitted virus to the progeny. While ducklings exhibited a fairly uniform inflammatory response to the virus, duck hepatitis B virus inoculation of the goslings resulted in both inflammation and an altered hepatocellular morphology not seen in uninjected controls. The host range of duck hepatitis B virus appears to be limited to the primary host and a close taxonomic relative, similar to other members of the hepadnavirus family, hepatitis B virus and ground squirrel hepatitis virus.
Aflatoxin content of foods served to a population with a high incidence of hepatocellular carcinoma
Authors: Lohiya Ghanshyam , Nichols Laura , Hsieh Dennis , Lohiya Sunita , Nguyen Hoan
Published: March 2007

During three seasons, 36 samples of foods served to mentally retarded clients with a high incidence of hepatocellular carcinoma were analyzed for aflatoxin. Aflatoxin was not detected (less than 5 ppb) by thinlayer liquid chromatography in 35 food samples containing peanuts, corn, wheat or milk. One peanut butter sample contained 20 ppb aflatoxin. Aflatoxin content of these foods was at or below the level permitted by the Food and Drug Administration. Aflatoxin is probably not responsible for liver disease in this population.
Effects of peritoneovenous shunting: Out of the mouths of babes
Authors: Koretz Ronald L. , Conn Harold O.
Published: March 2007

The effect of peritoneovenous shunting on body composition has been studied in 7 cirrhotic patients undergoing a successful shunt and 3 patients in whom the shunt was unsuccessful. In the 7 patients with functioning shunts, their weight had decreased by a mean of 9 kg (p < 0.001) by 6 wk after initial diuresis, natriuresis, and kaliuresis, and was associated with a decrease in total body potassium (TBK) but not total body nitrogen (TBN). This resulted in a significant decrease in the TBK/TBN ratio from 2.12 ± 0.74 to 1.66 ± 0.20 (p < 0.01). By a mean of 14 mo, in these 7 patients there was a significant increase in mean TBN (from 1.54 ± 0.10 to 1.84 ± 0.10, p < 0.005) associated with an improvement in the mean nitrogen index (from 0.74 ± 0.04 to 0.88 ± 0.04, p < 0.005). These changes were associated with a significant increase in nonalcoholic calories, a nonsignificant increase in protein consumption, and a positive nitrogen balance. After the initial kaliuresis, mean potassium balance remained constantly positive (+22.7 ± 3.4 mmol/day), serum aldosterone levels normalized, and TBK increased. In contrast, 3 patients with failed peritoneovenous shunting continued to lose weight significantly despite the presence of ascites; TBN and nitrogen index also decreased. In conclusion, body composition studies appear to have confirmed the clinical observation that cirrhotic patients with massive ascites have depleted body protein which is gradually repleted only after successful shunting. In this situation TBK, long used as a measure of lean body mass, is less satisfactory than TBN and nitrogen index. This improvement in body protein appears to be explained by an increased dietary intake associated with improved nitrogen balance, but these changes are not found in patients in whom the shunt failed.
Epiphenomenology and the gallbladder: Several examples
Authors: Charlson Mary E.
Published: March 2007

It has been suggested that gallbladder removal may protect against subsequent development of myocardial infarction because of increased gastrointestinal cholesterol excretion resulting from increased enterohepatic cycling. To test this hypothesis, the authors used data from two large case-control studies of myocardial infarction--one conducted in 1976-1979 in 155 US hospitals and one conducted in 1980-1983 in 78 US hospitals. First, 550 female myocardial infarction cases were compared to 1,658 controls. Simultaneously adjusting for possible confounding variables using logistic regression, the odds ratio for development of a myocardial infarction subsequent to cholecystectomy was 0.8 (95% confidence interval, 0.5-1.1). Second, 1,511 male myocardial infarction cases were compared to 3,837 controls. With similar adjustments, the odds ratio was 0.8 (95% confidence interval, 0.5-1.2). The risk did not decline as the interval following cholecystectomy increased. The present data are compatible with a protective effect of cholecystectomy on the risk of subsequent myocardial infarction, but they are not conclusive.

This study was undertaken to assess possible modifications of the proliferative activity of co-Ionic mucosa, which could be related to a suggested cancer-promoting role of cholecystectomy. The mitotic index (number of mitoses per 1000 gland cells) was evaluated in the colonic mucosa of 14 healthy subjects, 11 patients with cholelithiasis, before and 6 months after surgery, and 10 patients who had undergone cholecystectomy 2 or more years previously. The mitotic index of cholecystectomized patients was significantly higher than controls. It rose significantly within 6 months of cholecystectomy. The mitotic index of patients with cholelithiasis before surgery was similar to controls. These data suggest that cholecystectomy is followed by an enhancement in the proliferative activity of the colonic mucosa, which could play a cancer-promoting role.
Sizing up portal hypertension: Better noninvasive methods are needed
Authors: Sovak Milog
Published: March 2007

The “congestion index” is used to mean the ratio between the cross-sectional area (cm2) and the blood flow velocity (cm/sec) of the portal vein, as determined by a duplex Doppler system. The indices as determined in normal subjects and patients with liver disease were as follows: normal subjects (n = 85), 0.070 ± 0.029 cm × sec; acute hepatitis (n = 11), 0.071 ± 0.014 cm × sec; chronic active hepatitis (n = 42), 0.119 ± 0.084 cm × sec; cirrhosis (n = 72), 0.171 ± 0.075 cm × sec; and idiopathic portal hypertension (n = 11), 0.180 ± 0.107 cm × sec. There was a statistically significant difference between the congestion indices from the normal subject group and indices obtained from patients with chronic hepatitis, cirrhosis, and idiopathic portal hypertension. A weak positive correlation was obtained between the congestion index and the portal venous pressure, measured simultaneously through a percutaneously placed catheter (n = 64, r = 0.45, p < 0.01). It is suggested that the congestion index reflects the pathophysiological hemodynamics of the portal venous system in portal hypertension.
Hepatic encephalopathy: Lack of changes of γ-aminobutyric acid content in plasma and cerebrospinal fluid
Authors: Moroni Flavio , Riggio Oliviero , Carlà Vincenzo , Festuccia Vittorio , Ghinelli Florio , Marino Ignazio R. , Merli Manuela , Natali Laura , Pedretti Giovanni , Fiaccadori Franco , Capocaccia Livio
Published: March 2007

The aim of the study was to verify the role of γ-aminobutyric acid in the pathogenesis of hepatic encephalopathy occurring in cirrhotic patients by attempting to correlate plasma and cerebrospinal fluid content of authentic γ-aminobutyric acid with the neurological manifestations of hepatic encephalopathy. For this purpose, plasma and cerebrospinal fluid γ-aminobutyric acid levels were measured by means of mass fragmentography in 17 cirrhotic patients with hepatic encephalopathy and in 6 cirrhotics without neurological symtoms. Moreover, in all patients, a second sample was obtained during the clinical course of hepatic encephalopathy.

The mean plasma and cerebrospinal fluid γ-aminobutyric acid levels were not different in patients with or without hepatic encephalopathy and did not change during the evolution of the neurological symptoms. The lack of changes in the γ-aminobutyric acid content in plasma and cerebrospinal fluid during hepatic encephalopathy is in contrast with the hypothesized importance of increased entry into the brain of γ-aminobutyric acid in the pathogenesis of hepatic encephalopathy.
Primary biliary cirrhosis: Associations with class II major histocompatibility complex antigens
Authors: Gores Gregory J. , Moore Breanndan S. , Fisher Lloyd D. , Powell Frank C. , Dickson Rolland E.
Published: March 2007

Tissue injury in primary biliary cirrhosis is thought to be mediated by immune mechanisms. Various Class II antigens of the major histocompatibility complex are associated with autoimmune diseases and their differing clinical manifestations. Thus, the aim of this study was to examine the relationship between primary biliary cirrhosis, its clinical manifestations and serologically defined Class II antigens (HLA-DR and HLA-DQ). Typing for these antigens was performed in 114 primary biliary cirrhotic patients and 171 controls by lymphocytotoxicity. There was a 6-fold increase in the frequency of HLA-DRw8 in primary biliary cirrhosis as compared to controls [30.1 vs. 4.7% (p < 0.0001)]. In contrast, HLA-DR5 had a decreased frequency in primary biliary cirrhosis as compared to controls [9.8 vs. 25.2% (p < 0.02)]. We examined the relationship between Class II antigens and the following prognostic indicators in primary biliary cirrhosis: serum bilirubin; 24-hr urine copper; serum albumin; prothrombin time; platelet count; ascites, and histologic stage (I to IV). Patients who are positive for HLA-DRw52 (n = 82) had a 2-fold increase in serum bilirubin compared to those who are negative (n = 32) for this antigen (p < 0.05). Conversely, patients who are positive for HLA-DR2 had less than half the serum bilirubin values of those negative for this antigen (p < 0.02). In conclusion, we found different Class II antigens to be associated with a prognostic indicator in primary biliary cirrhosis (serum bilirubin), while HLA-DRw8 is strongly associated with the disease itself. These data suggest that determining Class II antigens may be important in predicting the course and clinical expression of primary biliary cirrhosis.