Histological Evidence Of Liver Damage Research Articles

ADAM Metalloproteinase Domain 17 Regulates Cholestasis-Associated Liver Injury and Sickness Behavior Development in Mice.

Disintegrin and metalloproteinase domain-containing protein 17 (ADAM17) is a ubiquitously expressed membrane-bound enzyme that mediates shedding of a wide variety of important regulators in inflammation including cytokines and adhesion molecules. Hepatic expression of numerous cytokines and adhesion molecules are increased in cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), however, the pathophysiological role of ADAM17 in regulating these conditions remains unknown. Therefore, we evaluated the role of ADAM17 in a mouse model of cholestatic liver injury due to bile duct ligation (BDL). We found that BDL enhanced hepatic ADAM17 protein expression, paralleled by increased ADAM17 bioactivity. Moreover, inhibition of ADAM17 bioactivity with the specific inhibitor DPC 333 significantly improved both biochemical and histological evidence of liver damage in BDL mice. Patients with cholestatic liver disease commonly experience adverse behavioral symptoms, termed sickness behaviors. Similarly, BDL in mice induces reproducible sickness behavior development, driven by the upregulated expression of cytokines and adhesion molecules that are in turn regulated by ADAM17 activity. Indeed, inhibition of ADAM17 activity significantly ameliorated BDL-associated sickness behavior development. In translational studies, we evaluated changes in ADAM17 protein expression in liver biopsies obtained from patients with PBC and PSC, compared to normal control livers. PSC and PBC patients demonstrated increased hepatic ADAM17 expression in hepatocytes, cholangiocytes and in association with liver-infiltrating immune cells compared to normal controls. In summary, cholestatic liver injury in mice and humans is associated with increased hepatic ADAM17 expression. Furthermore, inhibition of ADAM17 activity improves both cholestatic liver injury and associated sickness behavior development, suggesting that ADAM17 inhibition may represent a novel therapeutic approach for treating patients with PBC/PSC.

Murine Models of Hepatitis A Virus Infection.

Mechanistic analyses of hepatitis A virus (HAV)-induced pathogenesis have long been thwarted by the lack of tractable small animal models that recapitulate disease observed in humans. Several approaches have shown success, including infection of chimeric mice with human liver cells. Other recent studies show that HAV can replicate to high titer in mice lacking expression of the type I interferon (IFN) receptor (IFN-α/β receptor) or mitochondrial antiviral signaling (MAVS) protein. Mice deficient in the IFN receptor show critical features of type A hepatitis in humans when challenged with human HAV, including histological evidence of liver damage, leukocyte infiltration, and the release of liver enzymes into blood. Acute pathogenesis is caused by MAVS-dependent signaling that leads to intrinsic apoptosis of hepatocytes.

Pulp Response to Lyophilized Bone in Rat Teeth

Background: This article will review different materials for the treatment of pulps of primary and young permanent teeth. However, innovations in materials and advances in biology suggest that there may soon be a convergence of therapies for teeth of either dentition needing pulp treatment. Objectives: The objective of this study was evaluated the pulp and liver response to biocompatible agents such as lyophilized bone in comparison with classical formocresol. Materials and Methods: Treatment was applied to the upper right and left first molar of each animal, for a total of 120 teeth. Six groups were established according to the agent used and the time elapsed (30, 45 and 60 days). In each group five livers were selected, and a control group subjected to no treatment was also evaluated. At the end of the study the rats were sacrificed and the samples were processed for histological evaluation. Analysis of variance (ANOVA) for repeated measures was used. Results: Dentinal bridge formation and reparative dentin reached higher values in the group treated with lyophilized bone. The formocresol treatment group showed increased inflammation and necrosis. Conclusions: Lyophilized bone afforded improved pulp tissue response. No histological evidence of liver damage was observed in any of the hepatic samples studied.

Administration of High Doses of Copper to Capuchin Monkeys Does Not Cause Liver Damage but Induces Transcriptional Activation of Hepatic Proliferative Responses

Liver cells respond to copper loading upregulating protective mechanisms. However, to date, except for liver content, there are no good indicators that identify individuals with excess liver copper. We hypothesized that administering high doses of copper to young (5.5 mg Cu · kg -1 . d -1 ) and adult (7.5 mg Cu · kg -1 . d -1 ) capuchin monkeys would induce detectable liver damage. Study groups included adult monkeys (2 females, 2 males) 3–3.5 y old at enrollment treated with copper for 36 mo (ACu); age-matched controls (1 female, 3 males) that did not receive additional copper (AC); young monkeys (2 female, 2 males) treated from birth with copper for 36 mo (YCu); and young age-matched controls (2 female, 2 males) that did not receive additional copper (YC). We periodically assessed clinical, blood biochemical, and liver histological indicators and at 36 mo the hepatic mRNA abundance of MT2a , APP , DMT1 , CTR1 , HGF , TGFβ , and NF?? only in adult monkeys. After 36 mo, the liver copper concentration was 4–5 times greater in treated monkeys relative to controls. All monkeys remained healthy with normal routine serum biochemical indices and there was no evidence of liver tissue damage. Relative mRNA abundance of HGF, TGFβ and NF?Bwas significantly greater in ACu than in AC monkeys. In conclusion, capuchin monkeys exposed to copper at doses up to 50 times the current upper level enhanced expression of genes related to inflammation and injury without clinical, blood biochemical, or histological evidence of liver damage.

Effect of alpha-naphthylisothiocyanate-induced liver injury on intestinal adaptation in a rat model of short bowel syndrome

Progressive hyperbilirubinemia and end-stage liver failure are among the most serious complications of short bowel syndrome (SBS), representing the principle cause of death in a majority of fatal cases. In the current study, we examined the effects of alpha-naphthylisothiocyanate (ANIT)-induced liver injury on intestinal adaptation in a rat model of SBS. Male rats were divided into four groups: Sham rats underwent bowel transection (n = 8), Sham liver-injury rats underwent bowel transection and IP injection of ANIT (100 mg/kg, n = 8), SBS rats underwent a 75% bowel resection, and SBS-ANIT rats underwent bowel resection and liver injury similar to group sham-ANIT (n = 8). Fourteen days after intervention, liver biopsies and intestinal samples were obtained and evaluated for liver damage and measures of intestinal adaptation. Real time PCR and Western blotting were used to determine the level of bax and bcl-2 mRNA and protein, and p-ERK protein levels. Statistical analysis was performed using the one-way ANOVA test, with p < 0.05 considered statistically significant. All ANIT-treated animals exhibited histological evidence of liver damage that was associated with the expansion of atypical ductal proliferation near the periportal areas, intense neutrophil infiltration in the liver, increased mitotic activity, Kupfer cells hyperplasia and fatty liver degeneration. ANIT-induced liver damage in bowel resected animals was associated with a significant decrease in all parameters of intestinal adaptation including bowel and mucosal weight in jejunum (twofold decrease) and ileum (twofold decrease), mucosal DNA in jejunum (fourfold decrease), mucosal protein in jejunum (threefold decrease) and ileum (threefold decrease), villus height in jejunum (38%) and ileum (34%), and crypt depth in jejunum (24%) and ileum (30%) compared to SBS animals. Both Sham-ANIT and SBS-ANIT rats demonstrated decreased enterocyte proliferation rates that were accompanied by decreased p-ERK protein levels. Lower apoptotic rates in jejunum (40%) and ileum (52%) in SBS-ANIT rats (vs. SBS) coincided with decreased bax mRNA and protein levels. In a rat model of SBS, ANIT-induced liver injury was associated with decreased enterocyte proliferation and inhibited intestinal adaptation.

Intestinal involvement during 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced chronic liver injury in a mouse model

Purpose Although a physiologic relationship between intestinal mucosal integrity and hepatic function has been previously described, the effect of primary liver disease on intestinal mucosal homeostasis has not been previously well documented. In the current study, we studied the effects of chronic liver injury as a primary injury on enterocyte turnover (proliferation and apoptosis) in a mouse model. Methods The liver toxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-enriched diet was used to induce chronic cholestatic liver injury in mice. Livers and intestine were harvested after 3 weeks of dietary treatment of histologic analysis and a determination of cell proliferation (immunohistochemistry for Ki67), or apoptosis (immunohistochemistry for caspase-3), as well as a determination of Wnt/ β-catenin signaling activity. Results All DDC-fed animals exhibited histologic evidence of liver damage that was associated with the expansion of atypical ductal proliferation near the periportal areas and increased oxidative stress. In the intestine, DDC-induced liver damage was associated with decreased villus height, decreased enterocyte proliferation, and increased cell apoptosis compared with control animals. There was also evidence for decreased β-catenin expression by immunostaining in crypt and villus cells of DDC-fed mice compared with control animals. Conclusion Primary liver injury and cholestasis is associated with intestinal mucosal hypoplasia. Decreased cell proliferation and increased cell apoptosis may be responsible for decreased intestinal epithelial cell mass. The observed decrease in cell turnover is accompanied by an alteration in Wnt/ β-catenin signaling.

Hepatotoxic Interaction of Sulindac with Lipopolysaccharide: Role of the Hemostatic System

Sulindac (SLD) is a nonsteroidal anti-inflammatory drug (NSAID) that has been associated with a greater incidence of idiosyncratic hepatotoxicity in human patients than other NSAIDs. One hypothesis regarding idiosyncratic adverse drug reactions is that interaction of a drug with a modest inflammatory episode precipitates liver injury. In this study, we tested the hypothesis that lipopolysaccharide (LPS) interacts with SLD to cause liver injury in rats. SLD (50 mg/kg) or its vehicle was administered to rats by gavage 15.5 h before LPS (8.3 x 10(5) endotoxin unit/kg) or its saline vehicle (i.v.). Thirty minutes after LPS treatment, SLD or vehicle administration was repeated. Rats were killed at various times after treatment, and serum, plasma, and liver samples were taken. Neither SLD nor LPS alone caused liver injury. Cotreatment with SLD/LPS led to increases in serum biomarkers of both hepatocellular injury and cholestasis. Histological evidence of liver damage was found only after SLD/LPS cotreatment. As a result of activation of hemostasis induced by SLD/LPS cotreatment, fibrin and hypoxia were present in liver tissue before the onset of hepatotoxicity. Heparin treatment reduced hepatic fibrin deposition and hypoxia and protected against liver injury induced by SLD/LPS cotreatment. These results indicate that cotreatment with nontoxic doses of LPS and SLD causes liver injury in rats, and this could serve as a model of human idiosyncratic liver injury. The hemostatic system is activated by SLD/LPS cotreatment and plays an important role in the development of SLD/LPS-induced liver injury.

The presence of an intrahepatic cytotoxic T lymphocyte response is associated with low viral load in patients with chronic hepatitis C virus infection

Background/Aims : The role of cytotoxic T lymphocytes (CTL) in limiting viral replication and producing hepatocellular injury in patients with chronic hepatitis C virus (HCV) infection is controversial. Methods : Intrahepatic and peripheral blood HCV-specific CTL activity against the entire HCV polyprotein was assessed in 26 patients. CTL responses were assessed after effector lymphocytes were re-stimulated for 6 days in vitro using HCV-vaccinia virus-infected autologous cells expressing HCV antigens. Serum and hepatic viral loads were measured and immunohistochemistry for CD3 and CD8 was performed to localise and enumerate effector cells in liver. Results : A positive CTL response was detected in 39/52 (75%) of assays conducted with intrahepatic mononuclear cells and 21/52 (40%) of peripheral blood assays ( P<0.001). The presence of an intrahepatic CTL response was associated with low hepatic viral load ( P=0.004). Hepatic lobular infiltration by CD8 +T cells correlated weakly with serum alanine aminotransferase levels ( r=0.42, P=0.04) and no relationship was demonstrated between CTL activity and histological evidence of liver damage. Conclusions : HCV-specific CTL activity is found more commonly in liver than in blood. An inverse relationship between CTL responses and viral load supports the hypothesis that HCV-specific CTL limit viral replication in patients with chronic HCV infection.

Histologic activity of childhood chronic hepatitis B related to viremia levels, genotypes, mutations, and epidemiologic factors.

Despite high viral load, children with chronic hepatitis B virus (HBV) infection may lack significant biochemical signs of liver dysfunction. Failure to develop abnormal liver chemistriesis is probably due to immunologic hyporeactivity. Despite the absence of biochemical abnormalities in these patients, there is still a risk for long-term complications. The pathogenic importance of viral load and genetic variability is less well studied in children than in adults. We evaluated viremia levels, genotypes, and mutations related to histologic evidence of liver damage in 71 HBV carriers, aged 2 to 18 years, all of non-Swedish origin. None of the of 22 children who were hepatitis B e antigen (HBeAg) negative had severe liver disease or had HBV DNA levels greater than 10 copies/mL (mean 10 ); 3 (14%) of them had increased alanine aminotransferase (ALT). The 49 HBeAg-positive children had a mean HBV DNA level of 10 copies/mL, and increased ALT was seen in 28 (55%). Core promoter mutations (at nt 1764) or precore mutations (at codon 1, 2, or 28) were rare; they were seen in four and one HBeAg-positive children, and in four and nine HBeAg-negative children, respectively, without association to liver damage. C-1858 was associated with more liver inflammation. Genotype did not significantly influence liver damage. Children with horizontal transmission had a faster rate of seroconversion and more inflammation of the liver. Severe HBeAg-negative hepatitis with high HBV DNA levels and mutations in the core promoter or precore regions seems to be less common in children than in adults. C-1858 strains may be more pathogenic, but this requires further study. Epidemiologic factors influence the course of infection.

Fatty liver vulnerability to endotoxin-induced damage despite NF-kappaB induction and inhibited caspase 3 activation.

Fatty livers are sensitive to lipopolysaccharide (LPS) damage. This study tests the hypothesis that this vulnerability occurs because protective, antiapoptotic mechanisms are not upregulated appropriately. Genetically obese, leptin-deficient ob/ob mice, a model for nonalcoholic fatty liver disease, and their lean litter mates were treated with a small dose of LPS. General measures of liver injury, early (i.e., cytochrome c release) and late (i.e., activation of caspase 3) events that occur during hepatocyte apoptosis, and various aspects of the signal transduction pathways that induce nuclear factor-kappaB (NF-kappaB) and several of its antiapoptotic transcriptional targets (e.g., inducible nitric oxide synthase, bfl-1, and bcl-xL) were compared. Within 0.5-6 h after LPS exposure, cytochrome c begins to accumulate in the cytosol of normal livers, and procaspase 3 cleavage increases. Coincident with these events, kinases (e.g., AKT and Erk-1 and -2) that result in the degradation of inhibitor kappa-B are activated; NF-kappaB activity is induced, and NF-kappaB-regulated gene products accumulate. Throughout this period, there is negligible histological evidence of liver damage, and serum alanine aminotransferase values barely increase over baseline values. Although ob/ob livers have significant histological liver injury and 11-fold greater serum alanine aminotransferase values than those of lean mice by 6 h post-LPS, they exhibit greater activation of AKT and Erk, more profound reductions in inhibitor kappa-B, enhanced activation of NF-kappaB, and greater induction of NF-kappaB-regulated genes. Consistent with this heightened antiapoptotic response, increases in cytochrome c and procaspase 3 cleavage products are inhibited. Together with evidence that ob/ob hepatocytes have a reduced ATP content and undergo increased lysis after in vitro exposure to tumor necrosis factor-alpha, these findings suggest that fatty livers are sensitive to LPS damage because of vulnerability to necrosis, rather than because of apoptosis.

IgM anti‐hepatitis C virus core antibodies as marker of recurrent hepatitis C after liver transplantation

The differential diagnosis of recurrent hepatitis C following orthotopic liver transplantation (OLT) may be difficult. We evaluated the diagnostic significance of IgM anti-hepatitis C virus (anti-HCV) core antibodies in 27 patients undergoing OLT because of HCV-associated cirrhosis. Serial serum samples collected before and after OLT were tested for the presence of IgM anti-HCV core antibodies. Results were compared with the histological evidence of liver damage, the presence, level, and genotype of serum HCV RNA and the degree of immunosuppression. All patients underwent recurrent HCV infection. Recurrent hepatitis was diagnosed histologically in 21 patients an average of 48 weeks after OLT (range 2–209 weeks): 18 had persistence or (re)appearance of the IgM anti-HCV core after OLT, one lost the IgM anti-HCV core after OLT, and two never secreted IgM anti-HCV core either before or after OLT. The remaining six patients did not develop recurrent hepatitis after a follow-up of 44–241 weeks from OLT; in these patients, IgM anti-HCV core either disappeared (1 case) or decreased (1 case) after OLT or were persistently negative throughout the study (4 cases). Thus, 18/21 patients with recurrent hepatitis, but only one of six without recurrent hepatitis, secreted IgM anti-HCV core after OLT (P < 0.05). The IgM anti-HCV core levels were not correlated with the level or genotype of serum HCV RNA or the degree of immunosuppression. In conclusion, secretion of IgM anti-HCV core antibodies after OLT seems associated with recurrence of HCV-associated liver disease and may have diagnostic significance. J. Med. Virol. 56:224–229, 1998. © 1998 Wiley-Liss, Inc.

IgM anti-hepatitis C virus core antibodies as marker of recurrent hepatitis C after liver transplantation

The differential diagnosis of recurrent hepatitis C following orthotopic liver transplantation (OLT) may be difficult. We evaluated the diagnostic significance of IgM anti-hepatitis C virus (anti-HCV) core antibodies in 27 patients undergoing OLT because of HCV-associated cirrhosis. Serial serum samples collected before and after OLT were tested for the presence of IgM anti-HCV core antibodies. Results were compared with the histological evidence of liver damage, the presence, level, and genotype of serum HCV RNA and the degree of immunosuppression. All patients underwent recurrent HCV infection. Recurrent hepatitis was diagnosed histologically in 21 patients an average of 48 weeks after OLT (range 2-209 weeks): 18 had persistence or (re-)appearance of the IgM anti-HCV core after OLT, one lost the IgM anti-HCV core after OLT, and two never secreted IgM anti-HCV core either before or after OLT. The remaining six patients did not develop recurrent hepatitis after a follow-up of 44-241 weeks from OLT; in these patients, IgM anti-HCV core either disappeared (1 case) or decreased (1 case) after OLT or were persistently negative throughout the study (4 cases). Thus, 18/21 patients with recurrent hepatitis, but only one of six without recurrent hepatitis, secreted IgM anti-HCV core after OLT (P < 0.05). The IgM anti-HCV core levels were not correlated with the level or genotype of serum HCV RNA or the degree of immunosuppression. In conclusion, secretion of IgM anti-HCV core antibodies after OLT seems associated with recurrence of HCV-associated liver disease and may have diagnostic significance.

Hepatitis G virus infection among liver graft recipients: anatomoclinical correlations.

Hepatitis G virus (HGV) causes persistent infection in man, but its disease association is controversial. We studied the HGV disease association in 25 liver transplantation (LT) recipients without evidence of hepatitis B and C infection. HGV RNA was tested by semiquantitative RT-PCR in serial serum samples and its presence was correlated with the biochemical and histological evidence of liver damage. The overall prevalence of HGV infection in this population was 9/25 (36%), one patient being HGV RNA positive since before LT, while the other eight apparently acquired de novo infections after LT. In five cases, appearance of HGV was followed by biochemical and histological evidence of liver damage: the liver biopsy showed acute rejection in two cases, acute cholangitis in two, and acute hepatitis in one. At the end of follow-up, histological evidence of chronic hepatitis was found in one HGV-positive patient but also in three HGV-negative patients, whereas the only patient with acute hepatitis at the time HGV RNA was first detected in serum developed an intralobular gigantocellular granuloma. In conclusion, HGV infection after LT may be seldom associated with acute and chronic liver damage, but comparable histological features can be observed also among HGV-negative controls.

Hepatic arterial infusion of verapamil and doxorubicin with complete hepatic venous isolation and extracorporeal chemofiltration: pharmacological evaluation of reduction in systemic drug exposure and assessment of hepatic toxicity

Tumour resistance to chemotherapeutic drugs through expression of the multidrug resistance phenotype is a major impediment in the treatment of hepatic malignancies. We performed hepatic arterial infusion of verapamil (at a dose known to block P-glycoprotein activity) and doxorubicin combined with complete hepatic venous isolation and extracorporeal chemofiltration in non-tumour-bearing pigs with normal livers to evaluate the pharmacology and toxicology of this drug combination. The complete hepatic venous isolation-chemofiltration system significantly reduced system exposure to both verapamil and doxorubicin ( P <0.01). Hepatic arterial infusion of verapamil (2 mg/kg) alone did not result in hepatocellular toxicity. However, the combination of verapamil and doxorubicin (3 mg/kg or 5 mg/kg) produced significant elevations in liver enzymes ( P < 0.01), and gross histological evidence of liver damage in 90% of the treated animals. The results of this study indicate that hepatic arterial infusion of verapamil and doxorubicin, in an attempt to improve treatment response in unresectable liver tumours expressing the multidrug resistance phenotype, may not be tolerated by patients with limited hepatic reserve.

Comparison of the hepatic and testicular effects of orally administered Di(2-ethylhexyl) phthalate and dialkyl 79 phthalate in the rat

A study was conducted on the effect of oral administration of either di(2-ethylhexyl) phthalate (DEHP) or dialkyl 79 phthalate (DA79P) at a dose level of 2500 mg/kg/day for 7 and 21 days in young male and female Wistar albino rats. Both DEHP and DA79P increased liver size in both sexes and reduced the relative weitht of testes in male rats. Liver enlargement was accompanied by alterations in several marker enzyme activities. Both DEHP and DA79P depressed mitochondrial succinate dehydrogenase in male but not in female animals. While certain parameters of hepatic xenobiotic metabolism were elevated in female rats receiving either DEHP or DA79P, a marked inhibition of xenobiotic metabolism was observed in male rats treated with DA79P. Parallel morphological investigations revealed histological evidence of liver damage in maie rats given DA79P and ultrastructural investigation revealed changes in the structure of the nuclei, mitochondria, and endoplasmic reticulum. These effects were largely absent from female animals. DEHP produced no hepatic histological changes in either sex but ultratructural studies indicated proliferation of the smooth endoplasmic reticulum, an increase in the numbers of microbodies (peroxisomes), and mitochondrial changes. Treatment of rats with either DEHP or DA79P resulted in hepatic changes, although the effects were not necessarily common to both agents. Male animals appeared to be more susceptible than female animals. Finally, both agents.caused testicular atrophy as indicated by decreased testicular weight and atrophy of seminiferous tubules in male rats treated for 21 days.

The role of iron in the toxicity of 2,3,7,8-tetrachlorodibenzo-( p)-dioxin (TCDD)

The effects of TCDD on normal and iron-deficient mice fed a casein-based diet were compared. Liver damage, porphyria, and thymic atrophy were studied in C57B1/6J mice, chloracne and liver damage in the HRS/J strain. Sequential pathologic changes also were studied in C57B1/6J mice fed laboratory chow and treated with TCDD (25 μg/kg/week). Steatosis was present by Day 4; cell swelling, necrosis, and disorganization of the acinar architecture followed with maximal effects from weeks 4 to 8. Widespread necrosis of liver and cholangiofibrosis were late changes. The disturbance of porphyrin metabolism was localized to zone III. Mice fed a low iron diet supplemented with 0.05% w w Fe and treated with TCDD (25 μg/kg/week × 12 weeks) developed porphyria after 15 weeks; venesected mice not supplemented with iron had not developed porphyria by 20 weeks. In general, an interaction was noted between TCDD and iron as judged by the rapidity of onset and severity of the porphyria. Iron-deficient and iron-supplemented groups of C57B1/6J mice received 37.5 μg/kg of TCDD. After 5 days there was an equal decrease in thymus weight in both groups of animals but histologic evidence of liver damage was less in the low iron mice. TCDD (45 μg/kg) was applied to the skin of iron-deficient and iron-supplemented hairless (HRS/J) mice. After 3 weeks chloracne developed irrespective of iron status; liver porphyrin was normal in the low iron animals but increased 100-fold in iron-supplemented mice in which histologic damage was also more severe. In general, iron deficiency did not decrease the activity of the hepatic mixed-function oxygenase systems. We conclude that iron deficiency protects against porphyria due to TCDD but that protection by iron deficiency against histologic damage to the liver is incomplete. In contrast, iron deficiency did not affect thymic atrophy or chloracne caused by TCDD.

Intrafamilial spread of hepatitis B virus infection. (Role of chronic hepatitis and of the hepatitis B e antigen).

Two hundred and forty household contacts of 85 chronic HBsAg carriers were studied to assess the relationship between liver histology and 'e' antigen or antibody positivity in the index carrier, and evidence of HBV infection within the family. Liver biopsy results were available in 54 index carriers. The prevalence of HBsAg and anti-HBs in the families of 29 carriers with chronic hepatitis and 25 carriers with either a normal liver or minimal inflammatory changes was not significantly different. Serum from 72 index carriers was available for HBeAg and anti-HBe testing. The prevalence of HBsAg and anti-HBs in the families of 5 HBeAg positive carriers, 59 anti-HBs positive subjects, and 8 carriers negative for both HBeAg and anti-HBe was again not significantly different. Infectivity of a carrier thus does not appear to correlate either with histological evidence of liver damage or with the 'e' antigen or antibody positivity of the carrier.

Toxicity studies of liposome-encapsulated immunomodulators administered intravenously to dogs and mice

Multilamellar liposomes containing lymphokines from mitogen-stimulated rat lymphocytes were injected IV into BALB/c or (C57BL/6×C3H)F1 mice and Beagle dogs to evaluate their potential toxicity. Animals received either single or multiple (×3, ×4, or ×6) injections. All animals receiving liposomes remained clinically healthy. No hematologic changes were detected in liposome-treated mice, but lymphocytosis was detected in the treated dogs. Slight elevation of serum alkaline phosphatase and glutamine oxalo-acetic transaminase levels was also found in treated dogs, and occasional animals showed elevated serum bilirubin levels. No histologic evidence of liver damage was found in these animals. No gross or histologic changes were detected in any major organ systems in treated animals. Mononuclear cells isolated from the peripheral blood of dogs that received liposome-encapsulated lymphokines IV were tested for in vitro cytotoxicity against allogeneic tumor cell lines. Lymphocyte-, monocyte-, and natural killer cell-mediated cytotoxicity in vitro was unaltered. Murine alveolar and peritoneal macrophages harvested 24 h after injection of liposome-encapsulated lymphokines exhibited significant tumoricidal activity in vitro, but activation depended on the route of liposome administration. These data indicate that liposome-encapsulated lymphokines do not cause significant toxicity in vivo and are able to activate macrophages in specific anatomic compartments.

Reducing the potential copper toxicity of concentrates to sheep by the use of molybdenum and sulphur supplements

A high copper (Cu) diet (45.3 μg Cu/g DM) was given to three groups of animals, ♂ or ♀ Scottish Blackface and ♂ Finnish Landrace lambs, without added molybdenum (Mo), or with 2, 4, 8 or 16 mg Mo/kg DM added in a 3 × 5 factorial experiment lasting 18–27 weeks. Sodium sulphate, providing 2 g S/kg, was added with each Mo supplement. Six of the nine lambs not given supplementary Mo + S died of Cu poisoning but those given Mo + S survived. Histological evidence of subclinical hepato-toxicity was found in Mo + S supplemented lambs but it decreased in severity as the level of added Mo increased. Plasma aspartate amino-transferase (PAAT) concentrations were elevated in unsupplemented lambs from week 9 and in lambs given 2 mg Mo/kg from week 12 but they remained normal in lambs given 4–16 mg Mo/kg DM. Successive increments in dietary Mo reduced the increase in liver Cu after 18–20 weeks from 1450 to 735, 483, 445 and 131 μg/g DM. The proportion of ingested Cu (y%) retained in the liver was related to dietary Mo ( x, mg/kg DM) by the equation y = 2.6 − 1.66 log x ± 0.21 ( r = 0.98; 2 d.f.). Finnish Landrace lambs retained 50% less Cu in their livers, had lower PAAT levels and showed less histological evidence of liver damage than ♂ Scottish Blackface lambs. The latter had higher PAAT levels and a higher mortality from Cu poisoning than ♀ Scottish Blackface lambs although the two sexes retained similar proportions of ingested Cu in their livers. The results are discussed in relation to the practical use of Mo + S to prevent Cu poisoning in sheep.

CONTROLLED TRIAL OF CYSTEAMINE IN TREATMENT OF ACUTE PARACETAMOL (ACETAMINOPHEN) POISONING

A randomised controlled trial of the use of intravenous cysteamine in the treatment of severe paracetamol poisoning has been performed. Thirty-eight patients presenting 3-17 h after ingestion were admitted to the trial; of these eighteen received cysteamine. Two patients died from hepatic failure, one in each treatment group. Analysis of the series as a whole showed no advantage of cysteamine in preventing biochemical abnormalities of liver function except for aspartate aminotransferase and serum ferritin levels, which were significantly less after cysteamine therapy. Separate analysis of the patients treated within 9 h of paracetamol ingestion and of those treated 9-17 h after paracetamol ingestion similarly showed no definite advantage of cysteamine. Histological evidence of liver damage showed a possible beneficial effect of cys-