Mast cells and c-Kit expression in liver allograft rejection.

AIMS: The pathogenesis of rejection following liver transplantation is not fully understood. It has been postulated that mast cells may play a role in acute and chronic rejection of a number of other solid organ grafts. The aim of this study was to assess the possible role of mast cells and c-Kit+ cells in acute and chronic liver allograft rejection. METHODS AND RESULTS: Biopsy specimens from (i) 'time zero' grafts with a minimal degree of perfusion injury (controls), (ii) transplanted livers with different grades of acute rejection, and (iii) transplanted livers with end-stage chronic rejection, were stained immunohistochemically using monoclonal anti-mast cell tryptase and polyclonal anti-c-Kit antibodies. Tryptase- and c-Kit-positive cell densities were assessed by image analysis. Tryptase-positive mast cell densities (P<0.001) were strongly correlated with acute liver allograft rejection grades and chronic liver allograft rejection. Furthermore, a similarly strong relationship was found between c-Kit+ cell densities and increasing rejection grade (P<0.001). CONCLUSIONS: Tryptase- and c-Kit-positive mast cells form part of the inflammatory infiltrate in both acute and chronic liver allograft rejection, and may be important effector cells in these processes.

Amelioration of lead toxicity on rat liver with Vitamin C and silymarin supplements.

The aim of the present study was to investigate the impact of the combined administration of Vitamin C and silymarin on lead toxicity. Male albino rats were subdivided into three groups: the first was a control group, the second received lead acetate in diet as 500 mg/kg diet daily, the third received the same lead acetate dose and supplemented with Vitamin C (1 mg/100g body weight) and silymarin (1 mg/100g body weight) by gastric tube three times per week. Blood samples were taken after 2, 4 and 6 weeks of treatment. Significant lead-induced elevations in serum ALT, AST, GGT and ALP activities were observed after different periods of treatment. However, serum LDLc was decreased. The intensities of RNA and apoptotic fragments of DNA were measured as optical density by Gel-pro program. Lead acetate decreased the intensity of DNA at 6 weeks and induced apoptotic DNA fragments reversibly with time. After 2 weeks of lead administration dilation and congestion of terminal hepatic veins and portal vein branches were observed. Lead also induced hepatocyte proliferation without any localized distribution among zones 1-3. Portal inflammatory infiltrate with disruption of the limiting plates (interface hepatitis), steatosis, apoptosis and mild fibrosis were detected especially by sixth week of lead administration. Combined treatment of lead-exposed animals with Vitamin C and silymarin showed marked improvement of the biochemical, molecular and histopathological findings. These experimental results strongly indicate the protective effect of Vitamin C and silymarin against toxic effects of lead on liver tissue.

Prevalence of hantavirus antibody in patients with chronic renal disease in Egypt.

In Egypt, the etiology of chronic renal failure (CRF) is not well defined. A hospital-based case-control study was initiated in February 1998, to determine whether hantavirus infection is involved in chronic renal disease (CRD) in Egypt. The study enrolled 350 study patients with a history of CRF and 695 matched controls with CRD due to renal calculus or renal cancer, but with normal renal functions. Sera from cases and controls were tested for anti-hantavirus IgG using ELISA with a cell-lysate antigen from Hantaan virus prototype strain 76-118. A demographic questionnaire was completed for each study participant. Five of the 350 cases (1.4%), and seven of the 695 controls (1.0%) were antibody-positive to hantavirus, with a titer > or =1:400. The difference in antibody prevalence between the study cases and the control cases was not statistically significant (P = 0.48). All antibody-positive study cases and controls had been exposed to rodents. Data indicated that in Egypt, hantavirus seroprevalence in CRD patients is low, and hantavirus infections do not appear to be a significant cause of CRF.

HCV-associated hepatocellular carcinoma without cirrhosis.

BACKGROUND/AIMS: Hepatocellular carcinoma is an aggressive malignancy and carries a poor prognosis. Hepatitis B and C virus infection, cirrhosis and aflatoxin B1 exposure are considered major risk factors. The role of hepatitis C virus in the causation of hepatocellular carcinoma has been debated. It is a positive, single-stranded RNA virus without a DNA intermediate in its replicative cycle, so that integration of hepatitis C virus nucleic acid sequences into the host genome seems unlikely. The most plausible explanation of hepatitis C virus-associated hepatocellular carcinoma so far is that the virus causes necroinflammatory hepatic disease with vigorous regeneration, fibrosis, and eventually cirrhosis. The aim of this study was to examine the relationship of hepatitis C, cirrhosis and hepatocellular carcinoma. METHODS: Sixty-six consecutive patients with hepatocellular carcinoma undergoing resection or transplantation at the Royal Free Hospital were reviewed. A combination of serological data and polymerase chain reaction assay was used to assign hepatitis C virus and hepatitis B virus infection. RESULTS: We found four HCV-RNA positive patients with hepatocellular carcinoma without cirrhosis. All four cases were positive for HCV-RNA and negative for all markers of hepatitis B virus infection. CONCLUSIONS: These four cases show that hepatocellular carcinoma may develop in patients with hepatitis C virus without pre-existing cirrhosis. However, the precise role of hepatitis C virus in hepatocarcinogenesis, the carcinogenic potential of the different genotypes and whether this role is influenced by other risk factors still have to be clarified.

Otoacoustic emission versus ABR screening: the effect of external and middle ear abnormalities in a group of SCBU neonates.

Twenty neonates in a special care baby unit (SCBU) were tested using automated procedures for obtaining auditory brainstem responses (ABR) and transient evoked otoacoustic emissions (TEOAE). All 40 ears passed the initial ABR screen, while the pass rate for the TEOAE screen was only 52.5%. Ears with no external or middle ear abnormalities (group A) had a significantly higher TEOAE pass rate (94.7%) than those with at least one abnormality (group B) as detected by otoscopic examination and tympanometry (14.3%). Other variables, such as age at test, gestational age at birth and birth weight, did not differ significantly between groups A and B. We conclude that external/middle ear abnormalities in this group of neonates had no effect on the ABR screening results, but had a significant effect on the TEOAE screening results.

Hepatitis C virus-polymerase chain reaction of routinely processed liver biopsies.

The aim of the study was to evaluate the specificity and sensitivity of detection of hepatitis C virus (HCV)-RNA in formalin-fixed paraffin-embedded (FFPE) liver biopsies by polymerase chain reaction (PCR). Routinely processed FFPE diagnostic needle liver biopsies as well as stored serum samples from 43 patients with liver disease were tested for HCV-RNA by reverse transcription-nested PCR using the same sets of primers and following strict anticontamination measures. Twenty-nine cases were positive and 14 were negative for serum HCV-RNA. Tissue HCV-RNA was detected in 17 out of the 29 serum HCV-RNA-positive cases but not in any of the 14 serum HCV-RNA-negative cases. Compared to serum-PCR, tissue-PCR was 100% specific, 58.6% sensitive, and 72% efficient. HCV-RNA was detected more frequently in biopsies stored for less than 1 year, than in those stored for more than 1 year (P = 0.046). In biopsies stored for up to 1 year detection of HCV-RNA by PCR was 81.8% sensitive and 90.9% efficient. Short (< 0.5 cm) liver biopsies were as sufficient for nucleic acid extraction and amplification as long (> 0.5 cm) ones. It is concluded that following strict anticontamination measures, HCV-RNA detection by PCR in routinely fixed, processed, and stored diagnostic liver biopsies provides a valuable adjunct to diagnosis of HCV infection. In this study, this option was free from contamination problems, even though routine batch histological processing schedules were used.

Assessment of lead toxicity in traffic controllers of Alexandria, Egypt, road intersections.

Blood lead level (BPbL) was determined in forty-five traffic controllers working on Alexandria road intersections. Central nervous system dysfunction in the subjects studied was investigated by means of performance tests. Biochemical indicators related to lead exposure such as delta-aminolevulinic acid dehydratase and hemoglobin in their blood were also determined. Results indicated that most of the subjects studied have a comparably high BPbL. They also showed significantly poorer performance scores than that obtained in a previous study with a group of textile workers of the same age and educational levels. The mean of the BPbL in the traffic controllers was found to be 68.28 +/- 13.22 micrograms/dl. This is a very high level compared to an acceptable level of 30.00 micrograms/dl. All neurobehavioral symptoms demonstrated in the traffic controllers could be attributed to a high level of lead exposure.