In Vivo Identification, Survival, and Functional Efficacy of Transplanted Hepatocytes in Acute Liver Failure Mice Model by Fish Using Y-Chromosome Probe

Hepatocyte transplantation has excited much interest in lending temporary metabolic support to a failing liver following acute liver injury. The exact site from which they act and the clinical, biochemical, and histological changes in the recipient body following hepatocyte transplantation is yet to be worked out. The present study is an attempt to delineate location and function of transplanted hepatocytes and also the overall survival of these cells with a fluorescent in situ hybridization (FISH) technique using a Y-chromosome–specific probe in a carbon tetrachloride (CCl4)-induced mice model of fulminant hepatic failure. Fifty-five syngenic adult Swiss female mice of approximately the same age and body weight were divided into three groups. Group-1 (n = 15), which received mineral oil, served as a negative control. Group-II (n = 15) received CCl4 (3 mL/kg) 40% vol/vol in mineral oil, by gavage served as positive control for hepatic failure. Group-III (n = 25) received intrasplenic transplantation of syngenic single cell suspension of hepatocytes in Hanks medium, after 30 h of CCl4 administration. Male Swiss adult mice (n = 15) served as donors of hepatocytes. The overall survival of animals in groups I to III was 100, 0, and 70%, respectively, by 2 wk of the study period. Transplanted hepatocytes were identified by Periodic Acid Schiff (PAS) staining and confirmed with a FISH technique using the Y-chromosome probe. The majority of exogenously transplanted hepatocytes were found in the liver and spleen sections even after 1 wk of hepatocyte transplantation. Transplanted cells were mostly found to be translocated into the sinusoids of the liver. Transplanted hepatocytes were found to be beneficial as a temporary liver support in a failing liver, significantly improving the survival of the animals. In the present study, the FISH technique was used to unequivocally distinguish the transplanted cells from the host, and thus describes a model for studying the distribution and survival of the transplanted cells.

Phylogenetic analysis, based on EPIYA repeats in the cagA gene of Indian Helicobacter pylori, and the implications of sequence variation in tyrosine phosphorylation motifs on determining the clinical outcome

The population of India harbors one of the world's most highly diverse gene pools, owing to the influx of successive waves of immigrants over regular periods in time. Several phylogenetic studies involving mitochondrial DNA and Y chromosomal variation have demonstrated Europeans to have been the first settlers in India. Nevertheless, certain controversy exists, due to the support given to the thesis that colonization was by the Austro-Asiatic group, prior to the Europeans. Thus, the aim was to investigate pre-historic colonization of India by anatomically modern humans, using conserved stretches of five amino acid (EPIYA) sequences in the cagA gene of Helicobacter pylori. Simultaneously, the existence of a pathogenic relationship of tyrosine phosphorylation motifs (TPMs), in 32 H. pylori strains isolated from subjects with several forms of gastric diseases, was also explored. High resolution sequence analysis of the above described genes was performed. The nucleotide sequences obtained were translated into amino acids using MEGA (version 4.0) software for EPIYA. An MJ-Network was constructed for obtaining TPM haplotypes by using NETWORK (version 4.5) software. The findings of the study suggest that Indian H. pylori strains share a common ancestry with Europeans. No specific association of haplotypes with the outcome of disease was revealed through additional network analysis of TPMs.

Human fetal liver-derived stem cell transplantation as supportive modality in the management of end-stage decompensated liver cirrhosis

Liver transplantation is the only existing modality for treating decompensated liver cirrhosis. Several factors, such as nonavailability of donors, combined with operative risks, complications associated with rejection, usage of immunosuppressive agents, and cost intensiveness, make this strategy available to only a few people. With a tremendous upsurge in the mortality rate of patients with liver disorders worldwide, there is a need to search for an alternative therapeutic tool that can combat the above limitations and serve as a supportive therapy in the management of liver diseases. Cell therapy using human fetal liver-derived stem cells can provide great potential to conservatively manage end-stage liver diseases. Therefore, the present investigation aimed to study and prove the safety and efficacy of human fetal liver-derived stem cell transplantation in patients with end-stage liver cirrhosis. Twenty-five patients with liver cirrhosis of different etiologies were infused with human fetal liver-derived stem cells (EpCAM+ve) labeled with Tc-HMPAO through hepatic artery. Our high throughput analysis using flow cytometry, RT-PCR, and cellular characterization exemplifies fetal liver cells with their high proliferation rate could be the best source for rejuvenating the diseased liver. Further, no episodes related to hepatic encephalopathy recurred in any of the subjects following hepatic stem cell transplantation. There was marked clinical improvement observed in terms of all clinical and biochemical parameters. Further, there was decrease in mean MELD score (p < 0.01) observed in 6 months follow-up in all patients. Therapy using human fetal liver stem/progenitor cells offers a potentially supportive modality to organ transplantation in the management of liver diseases.

Human fetal liver-derived stem cell transplantation as supportive modality in the management of end-stage decompensated liver cirrhosis

Liver transplantation is the only existing modality for treating decompensated liver cirrhosis. Several factors, such as nonavailability of donors, combined with operative risks, complications associated with rejection, usage of immunosuppressive agents, and cost intensiveness, make this strategy available to only a few people. With a tremendous upsurge in the mortality rate of patients with liver disorders worldwide, there is a need to search for an alternative therapeutic tool that can combat the above limitations and serve as a supportive therapy in the management of liver diseases. Cell therapy using human fetal liver-derived stem cells can provide great potential to conservatively manage end-stage liver diseases. Therefore, the present investigation aimed to study and prove the safety and efficacy of human fetal liver-derived stem cell transplantation in patients with end-stage liver cirrhosis. Twenty-five patients with liver cirrhosis of different etiologies were infused with human fetal liver-derived stem cells (EpCAM+ve) labeled with Tc-HMPAO through hepatic artery. Our high throughput analysis using flow cytometry, RT-PCR, and cellular characterization exemplifies fetal liver cells with their high proliferation rate could be the best source for rejuvenating the diseased liver. Further, no episodes related to hepatic encephalopathy recurred in any of the subjects following hepatic stem cell transplantation. There was marked clinical improvement observed in terms of all clinical and biochemical parameters. Further, there was decrease in mean MELD score (p < 0.01) observed in 6 months follow-up in all patients. Therapy using human fetal liver stem/progenitor cells offers a potentially supportive modality to organ transplantation in the management of liver diseases.

In vitro insulin production and analysis of pancreatic transcription factors in induced human hepatic progenitor cells

BACKGROUND

beta-Cell destruction and/or insufficient insulin production are the hallmarks of diabetes mellitus (type 1 diabetes). A hepatic progenitor from developing liver is sought to be one of the surrogate sources of insulin production as the pancreas and the liver share a common precursor and signals from the cardiac mesoderm. Production of insulin is possible by transfecting pancreatic transcription factors that play important roles in development of the pancreatic beta-cell. But, there is always the fear of using genetically manipulated cells for therapeutics. Hence, the present study was designed to analyze the feasibility of using primary human fetal hepatic progenitors as a potential source for insulin production.

METHODS

Human fetal hepatic progenitors were enriched using CD-326 magnetic cell sorting. The sorted cells were cultured with different concentrations of glucose (5-30 mM) in Dulbecco's modified Eagle's medium. The amount of insulin production was estimated in the cultured cells by the chemiluminescence method. Total RNA isolated from sorted epithelial cell adhesion molecule (EpCAM)-positive cells was reverse-transcribed, and the expression of different beta-cell-producing transcriptions factors was analyzed by polymerase chain reaction (PCR). Immunocytochemical analysis was performed in cultured cells using specific insulin antibodies.

RESULTS

The viability of the total liver cells isolated was found to be 95%. The average number of EpCAM-positive cells in the total liver was found to be approximately 15%. An insulin kinetics study using glucose induction with different concentrations showed increased insulin secretion in response to glucose concentrations up to 20 mM. Furthermore, results of immunocytochemical analysis demonstrated intense insulin expression in EpCAM-positive cultured cells. Expression studies of the cultured EpCAM-positive cells using reverse transcription-PCR showed positive expression of the pancreatic transcription factors essential for insulin production.

CONCLUSIONS

The present study demonstrates that in vitro differentiation of induced human hepatic progenitors into insulin-producing cells without genetic manipulations may promote strategies for the treatment of type 1 diabetes.

Relevance of Helicobacter pylori genotypes in gastric pathology and its association with plasma malondialdehyde and nitric oxide levels

Persistent infection with Helicobacter pylori confers an increased risk of peptic ulceration and gastric adenocarcinoma. Reactive oxygen and nitrogen species play a crucial role in the progression from normal gastric mucosa to cancer. The aim of the present study was to investigate the plasma malondialdehyde and nitric oxide levels in H. pylori related gastroduodenal diseases and associate their levels with gastric pathology and genotypes of H. pylori. Malondialdehyde and nitric oxide levels in plasma samples of 250 subjects were spectrophotometrically determined. Subsequently, genotypic and histopathological assessment was performed in gastric biopsies obtained during endoscopy. The levels of MDA and NO exceeded in subjects infected with genotype-1 of Hp than those with other genotypes suggesting more precise interaction of highly virulent strains of Hp in eliciting severe tissue damage. In conclusion, the study demonstrates close relationship between the plasma malondialdehyde and nitric oxide levels, gastric histopathology and genotypes of H. pylori.

Neural stem cells & supporting cells--the new therapeutic tools for the treatment of spinal cord injury

Stem cells play important role in the development and in the maintenance of specific tissues. They have been identified in majority of the organs like liver, blood, skin and intestine. Role of stem cells in regenerative medicine have been implicated in many chronic diseases. Stem cell research is a new opportunity to those patients whose organs are damaged or diseased. The discovery of stem cells in central and peripheral nervous system is relatively recent. Spinal cord injury is one of the major neurological disaster affecting mostly young lives. Stem cell transplantation in spinal cord injury patients have shown encouraging results. Different sources of stem cells are being exploited for spinal cord injury as well as other neurological disorders.

Simplified and versatile method for bisulfite-based DNA methylation analysis of small amounts of DNA

Epigenetic alterations of gene function play a central role in the pathogenesis of many tumors and in the process of aging. Abnormal methylation at transcriptional sites of genes results in epigenetic silencing of the genes that protect against tumor formation or that repair DNA. To date, several studies have analyzed methylation status by oligonucleotide arrays, restriction analysis (COBRA), methylation-specific amplification, and sequence analysis. This requires high concentration of bisulfite-treated DNA, which mandates use of commercially available expensive kits, and is an often laborious and time-consuming task. In this article, we report a simplified high-throughput method, which can serve as a surrogate for screening methylation profiles of various genes and has high sensitivity compared with the other methods described previously.

Prevalence of hepatitis C virus (HCV) coinfection in HIV infected individuals in south India and characterization of HCV genotypes

PURPOSE

To determine anti-HCV antibodies and genomic subtype of HCV in 1487 confirmed human immunodeficiency virus (HIV) positive samples.

METHODS

A total of 1487 confirmed HIV-positive samples were tested for anti-HCV antibodies by using a third generation ELISA kit (Ortho 3.0) and by RT PCR for HCV. HIV and HCV coinfected samples were selected for HCV genotyping by RFLP and subtyping with NS5-type specific primers.

RESULTS

A total of 1487 HIV-infected serum samples were screened for HCV infection, of which, a 1443 (97.04%) were negative and 45 (3.02%) were coinfected. HIV-HCV coinfection was predominant in the age group 41-50 years (51.1%). HCV genotyping and subtyping was done for the 45 HCV RNA-positive specimens of which genotype 1 was observed in 31 (68.8%) and genotype 3 was observed in 14 (31.1%) subjects. Further subtyping analysis showed the genotype 1b in 23 (51.1%), 1a in eight (17.7%), 3a in 10 (22.2%) and 3b in four (8.8%) subjects.

CONCLUSION

HIV and HCV seroprevalence is higher in South India, and the most prevalent genotype in coinfection was genotype 1b.

Prognostic significance of genotyping Helicobacter pylori infection in patients in younger age groups with gastric cancer

BACKGROUND

Malignant tumours of the stomach are common, but the incidence of stomach cancer varies from country to country, probably a result of genetic, epigenetic and environmental factors. Stomach cancer often occurs in older people whose stomachs produce only small quantities of acid. Although infection with Helicobacter pylori has been proven beyond doubt in the aetiopathogenesis of various gastric disorders, not much is known about the genotypes of H pylori infection in early-onset gastric cancer.

AIM

To ascertain the genotypes of H pylori in gastric cancer.

METHODS

Ninety-two patients were separated into three groups on the basis of their endoscopic findings: group 1, gastric cancer; group 2, gastric ulcer; group 3, non-ulcer dyspepsia. Gastric biopsy specimens were obtained for culture and DNA isolation; additional specimens were taken from subjects with gastric cancer for histopathological analysis. Amplification was performed using specific oligonucleotide primers to obtain genotypic data. Four samples from each group were randomly selected for sequence analysis.

RESULTS

Genotypic analysis showed cagT+ve/hrgA+ve/cagA+ve/cagE+ve/vacAs1+ve to be highly prevalent in 79% of cases of H pylori infection. This genotype was found in 88% of subjects in group 1 and 78% in group 2. Intestinal-type adenocarcinoma was found in 35 subjects (83%), 32 (9%) of which harboured this genotype. Sequence analysis showed no significant strain-specific variations.

CONCLUSIONS

Certain genotypes of H pylori have higher predictive value for the development of intestinal-type carcinoma at an early age. Genotyping of H pylori may well be a useful tool for screening people at increased risk of developing malignancy.

Safety and efficacy of autologous bone marrow stem cell transplantation through hepatic artery for the treatment of chronic liver failure: a preliminary study

This study was performed to determine the safety and tolerability of injecting autologous bone marrow stem cells (BMC) (CD34+) into four patients with liver insufficiency. The study was based on the hypothesis that the CD34+ cell population in granulocyte colony stimulating factor (G-CSF) mobilized blood and autologous bone marrow contains a subpopulation of cells with the potential for regenerating damaged tissue. We separated the CD34+ stem cell population from the bone marrow. The potential of the BMC to differentiate into hepatocytes and other cell lineages has already been reported. Several reports have also demonstrated the plasticity of hematopoietic stem cells to differentiate into hepatocytes. Recently Sakaida demonstrated reduction in fibrosis in chemically induced liver cirrhosis following BMC transplantation. From a therapeutic point of view, chronic liver cirrhosis is one of the targets for BMC transplantation. In this condition, there is excessive deposition of extracellular matrix and hepatocyte necrosis. Encouraged by this evidence that the CD34+ cell population contains cells with the potential to form hepatocyte-like elements, four patients with liver insufficiency were given G-CSF to mobilize stem cells. CD34+ cells (0.1 x 10(8)) were injected into the hepatic artery. No complications or specific side effects related to the procedure were observed; four patients showed improvements in serum albumin, bilirubin and ALT after one month from the cell infusion.

Management of hyperbilirubinemia in biliary atresia by hepatic progenitor cell transplantation through hepatic artery: a case report

Cholangiodestruction of bile ducts leads to biliary atresia, a rare disease characterized by intrahepatic and extrahepatic biliary inflammation. If the intrahepatic biliary tree is unaffected, surgical reconstruction by the Kasai procedure of hepatoportoenterostomy of the extra hepatic biliary tract is possible. Untreated, this condition leads to cirrhosis and death within the first year of the life. If the atresia is complete, liver transplantation is the only option. As a result of the shortage of donor livers, hepatocytes have been infused over the past two decades, providing proof of the concept that cell therapy can be effective for the treatment of liver diseases. In the present study, we report a confirmed case of a girl of 1 year of age with increased bilirubin of 28.5 mg/dL and pediatric end-stage liver disease score 20. Biochemical liver function tests showed cholestasis (elevated cholesterol and gamma-GTs) and increased ALT, total bilirubin, conjugated bilirubin, and ALP. The patient was treated with hepatic progenitor cell infusion through the hepatic artery. The total bilirubin and conjugated bilirubin started decreasing during the first month after cell infusion. The level of total bilirubin maintained a threefold decrease after months of cell infusion. The conjugated bilirubin was 16.35 mg/dL before cell infusion, decreasing to eightfold after cell infusion. After 2 months of cell infusion, hepatobiliary scintigraphy showed increased liver cell function. This case demonstrated the efficacy and functionality of hepatic progenitor cells for the management of biliary atresia. Further, as there was a decrease in serum bilirubin, it showed that there was some percentage of the engraftment of the infused cells. As the procedure is simple and the patient has tolerated the infusion therapy, it might be repeated to manage biliary atresia.

A simple multiplex PCR assay for diagnosing virulent Helicobacter pylori infection in human gastric biopsy specimens from subjects with gastric carcinoma and other gastro-duodenal diseases

AIM

To evaluate and develop a multiplex polymerase chain reaction (PCR) assay for diagnosing and specific identification of virulent Helicobacter pylori strains and their main virulence genes cagA, cagE, cagT, vacA and hrgA.

METHODS AND RESULTS

Genomic DNA from 82 gastric tissues was screened. A master pool of all the ingredients of multiplex reaction was prepared for amplification. Amplicons were sequenced to confirm the amplification of each target genes. Multiplex PCR assay was able to detect all the five target genes in 81.7% and deletions in one or more loci among 18.3%. Genotype cagT +ve/hrgA +ve/cagA +ve/cagE +ve/vacAs1 +ve was more predominant in this study population (67.07%). hrgA, cagT, cagE and cagA genes were present in 100%, 92.7%, 85.4% and 81.7% of the subjects, respectively. The vacAs1 subtype had higher prevalence frequency in patients with overt gastrointestinal disease (78.57%) than with GERD (gastro-esophageal reflux disease) and NUD (non-ulcer dispepsia) (50%).

CONCLUSIONS

The multiplex PCR assay developed herein was able to genotype H. pylori isolates based on the main virulence genes.

SIGNIFICANCE AND IMPACT OF THE STUDY

The ability to identify H. pylori and the majority of their virulence gene markers by multiplex PCR assay represents a considerable advancement over other PCR-based methods for genotyping H. pylori from large population, and can be explored to gain insights at the genotypic variability exhibited by this pathogen.

Impact of household hygiene and water source on the prevalence and transmission of Helicobacter pylori: a South Indian perspective

INTRODUCTION

In developing countries, the Helicobacter pylori (H. pylori) infection rate is high, especially in lower socioeconomic groups. The populace in developing countries lives in conditions that are highly conducive to the acquisition of microorganisms. Poor hygiene, crowded household conditions and deficient sanitation mark their day-to-day life. We aimed to find out the roles of household hygiene and water source in the prevalence and transmission of H. pylori infection among the South Indian population using polymerase chain reaction (PCR) assay.

METHODS

The selected population consisted of 500 adults of varying ages ranging from 30 to 79 years, with upper gastrointestinal tract symptoms. Each participant in the study was given a questionnaire to complete. Samples to assess H. pylori infection included three gastric biopsies (two from the antrum and one from the corpus region). Infection was detected by PCR amplification of the 16S rRNA gene of H. pylori. The data was then examined statistically by univariate and multivariate analyses.

RESULTS

The overall prevalence of H. pylori was detected to be 80 percent. Prevalence increased with an increase in age and it was found to be 90 percent in the 70-79 year age group (p-value is less than 0.01). The prevalence of infection among people who drank water from wells was 92 percent compared with 74.8 percent of those who drank tap water (p-value is less than 0.001). H. pylori infection prevalence was found to be higher in people with low clean water index (CWI) (88.2 percent) than in those with higher CWI (33.3 percent) (p-value is less than 0.001). While the prevalence of H. pylori in the subjects with lower socioeconomic status was 86.1 percent, in higher groups, it was 70 percent (p-value is less than 0.001). The prevalence of H. pylori was also found to be higher in subjects who lived in overcrowded houses. It was 83.7 percent with high crowding index, 76.6 percent with medium crowding index, and 71.3 percent with low crowding index (p-value is less than 0.05).

CONCLUSION

The results of the present study suggest that the risk of acquisition and transmission of H. pylori can be prevented to a large extent by following improved household hygienic practices, proper waste disposal measures as well as the regular use of boiling water for drinking purposes.

Characterization of hepatic progenitors from human fetal liver using CD34 as a hepatic progenitor marker

AIM: To enrich putative hepatic progenitors from the developing human fetal liver using CD34 as a marker.

METHODS: Aborted fetuses of 13-20 wk were used for the isolation of liver cells. The cells were labeled with anti CD34; a marker used for isolating progenitor population and the cells were sorted using magnetic cell sorting. The positive fractions of cells were assessed for specific hepatic markers. Further, these cells were cultured in vitro for long term investigation.

RESULTS: Flow cytometric and immunocytochemical analysis for alphafetoprotein (AFP) showed that the majority of the enriched CD34 positive cells were positive for AFP. Furthermore, these enriched cells proliferated in the long term and maintained hepatic characteristics in in vitro culture.

CONCLUSION: The study shows that aborted human fetal liver is a potential source for isolation of hepatic progenitors for clinical applications. The study also demonstrates that CD34 can be a good marker for the enrichment of progenitor populations.

Stem Cell Therapy—Present Status

Stem cell research is a new field that is advancing at an incredible pace with new discoveries being reported from all over the world. Scientists have for years looked for ways to use stem cells to replace cells and tissues that are damaged or diseased. Stem cells are the foundation cells for every organ, tissue, and cell in the body. Stem cells are undifferentiated, "blank" cells that do not yet have a specific function. Under proper conditions, stem cells begin to develop into specialized tissues and organs. They are self-sustaining and can replicate themselves for long periods of time. Embryonic stem cells are pluripotent cells, isolated from the inner cell mass of the blastocyst-stage mammalian embryo. They have the ability to differentiate into several somatic or somatic-like functional cells such as neurons, hepatocytes, cardiomyocytes, and others. Adult stem cells are specialized cells found within many tissues of the body where they function in tissue homeostasis and repair. They are precursor cells capable of differentiation into several different cells. The knowledge of stem cells from various sources offered a new hope for the treatment of various diseases.

Antimicrobial activity of Sapindus mukorossi and Rheum emodi extracts against H pylori: In vitro and in vivo studies

AIM: To evaluate the antibacterial activity of Sapindus mukorossi (S. mukorossi) and Rheum emodi (R. emodi).

METHODS: Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylori, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram +ve (S. aureus, B. subtilis) and two Gram -ve (E. coli, P. vugaris) organisms were screened for their susceptibility patterns against these extracts.

RESULTS: In our screening, all 30 resistant isolates and the other four organisms (two Gram +ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris) were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited H pylori at very low concentrations. In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations (10 μg/mL) for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi (2.5 mg/mL) and R. emodi (3.0 mg/mL) given orally for seven days.

CONCLUSION: We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.

Journey from hepatocyte transplantation to hepatic stem cells: a novel treatment strategy for liver diseases

Acute liver failure (ALF) carries high morbidity and mortality (>80%) even in the best centres. Orthotopic liver transplantation (OLTx) is the only viable approach to the treatment of ALF. This has significantly improved the survival in these patients. The major limitations of OLTx are non availability of the donor liver, requirement of a major surgical procedure, high cost and longterm immunosuppression. Isolated hepatocyte transplantation is emerging as an appealing method for the treatment of ALF because of its technical simplicity and easy availability of cells. Transplantation of allogenic/xenogenic hepatocytes transplantation in experimentally induced ALF has shown an increased survival rate. Clinical studies in acute, chronic liver failure and metabolic disorders have also been undertaken in a few centres and have shown encouraging results. To maintain the continuous supply of cells, xenogenic source of hepatocytes (porcine, rabbit, canine) have offered a hope. A major concern regarding the use of xenogenic donors is the risk of transmission of zoonosis and immunogenicity. Recently, Porcine endogenous retrovirus (PERV) has been shown to infect human tissue in vitro. The problem of immunogenicity of xenogenic hepatocytes can be overcome to some extent by immunoisolation, encapsulation technique, which may also provide protection to the hepatocytes during cryopreservation. The knowledge of adult hepatic stem from tissue offered a new hope for the treatment of various chronic and metabolic diseases. Further, the transdifferentiation potentiality of haematopoietic stem cells to hepatic lineage has strengthened cell therapy.

Helicobacter pylori and other Helicobacter species DNA in human bile samples from patients with various hepato-biliary diseases

AIM: To investigate the presence of Helicobacter species by nested PCR of 16S rRNA genes followed by the presence of Helicobacter pylori（H pylori）16S rRNA, ureA, cagA genes in bile obtained at endoscopic retrograde cholangio-pancreatography (ERCP) from 60 Indian subjects.

METHODS: Sixty bile samples were obtained from patients diagnosed with various hepato-biliary diseases and control subjects at ERCP. PCR analysis was carried out using primers for Helicobacter genus 16S rRNA gene and H pylori (16S rRNA, ureA and cagA) genes. Gastric H pylori status was also assessed from biopsies obtained at endoscopy from patients with various hepato-biliary diseases and controls. The control group mainly consisted of subjects with gastric disorders. Sequencing analysis was performed to confirm that PCR products with 16S rRNA and cagA primers were derived from H pylori.

RESULTS No Helicobacters were grown in culture from the bile samples. Helicobacter DNA was detected in bile of 96.7% and 6.6% of groups I and II respectively. Ten from group I were positive for 16S rRNA and ureA and 9 were positive for cagA gene. In contrast of the 2 from the control, 1 amplified with 16S rRNA, ureA and cagA primers used. The sequences of the 16S rRNA genes and cagA were 99% similar to Helicobacter pylori.

CONCLUSION: Helicobacters are associated with the pathogenesis of various hepato-biliary disorders.

Prevalence study to elucidate the transmission pathways of Helicobacter pylori at oral and gastroduodenal sites of a South Indian population

INTRODUCTION

Since the discovery of Helicobacter pylori (H. pylori), much progress has been made worldwide in the field of its epidemiology. In spite of these advancements, many aspects of epidemiology still remain unclear, particularly among populations with low socio-economic status. The present study was designed to elucidate the different routes of transmission of H. pylori in the Hyderabad (South India) population and to investigate the impact of certain factors, such as age, gender, and lifestyle.

METHODS

Samples used for the study included saliva and biopsy samples of 400 symptomatic subjects from Hyderabad, India. The patients were retrospectively grouped, based on histopathology of the biopsy and 16S rRNA amplification of both saliva and biopsy as H. pylori positive and negative.

RESULTS

This study showed that the prevalence of H. pylori in both saliva and biopsy samples increased with age. In addition, the H. pylori infection was found more commonly in the saliva and biopsy samples among males (64 percent and 60 percent, respectively) than females (53.3 percent and 64 percent, respectively). Similarly, 71.6 percent and 73.5 percent of those who consumed municipal water acquired H. pylori (which were respectively found in their saliva and biopsy samples) compared to a lesser proportion (12.6 percent and 12.6 percent, respectively) of those who consumed boiled or filtered water. The study also found that subjects who preferred home-cooked food (57.1 percent and 57.7 percent) showed a lower prevalence of H. pylori in saliva and biopsy samples, respectively, compared to those (80 percent and 88 percent) who frequently ate out.

CONCLUSION

The results of the present study suggest that besides the oral-oral route, the transmission of H. pylori also takes place through the consumption of food prepared under unhygienic conditions. Consumption of municipal tap water also has a high impact in the transmission of H. pylori.

Association between cag-pathogenicity island in Helicobacter pylori isolates from peptic ulcer, gastric carcinoma, and non-ulcer dyspepsia subjects with histological changes

AIM: To investigate the presence of the cag-pathogenicity island and the associated histological damage caused by strains with complete cag-PAI and with partial deletions in correlation to the disease status.

METHODS: We analyzed the complete cag-PAI of 174 representative Helicobacter pylori (H pylori ) clinical isolates obtained from patients with duodenal ulcer, gastric ulcer, gastric cancer, and non-ulcer dyspepsia using eight different oligonucleotide primers viz cagA1, cagA2, cagAP1, cagAP2, cagE, cagT, LEC-1, LEC-2 spanning five different loci of the whole cag-PAI by polymerase chain reaction (PCR).

RESULTS: The complete screening of the genes comprising the cag-PAI showed that larger proportions of subjects with gastric ulcer (97.8%) inhabited strains with complete cag-PAI, followed by gastric cancer (85.7%), non-ulcer dyspepsia (7.1%), and duodenal ulcer (6.9%), significant differences were found in the percentage distribution of the genes in all the clinical groups studied. It was found that strains with complete cag-PAI were able to cause severe histological damage than with the partially deleted ones.

CONCLUSION: The cag-PAI is a strong virulent marker in the disease pathogenesis as it is shown that a large number of those infected with strain with complete cag-PAI had one or the other of the irreversible gastric pathologies and interestingly 18.5% of them developed gastric carcinoma. The presence of an intact cag-PAI correlates with the development of more severe pathology, and such strains were found more frequently in patients with severe gastroduodenal disease. Partial deletions of the cag-PAI appear to be sufficient to render the organism less pathogenic.

Rapid diagnosis of Helicobacter pylori infection in dyspeptic patients using salivary secretion: a non-invasive approach

INTRODUCTION

Current guidelines that recommend Helicobacter pylori eradication treatment without endoscopy in selected patients underscore the importance of non-invasive testing. The accuracy of saliva as a non-invasive specimen was compared with that of invasive tests in pretreatment diagnosis of H. pylori infection.

METHODS

One hundred patients undergoing gastroscopy were grouped into 80 symptomatic and 20 asymptomatic subjects and were investigated for the presence of H. pylori in saliva and stomach. Samples tested comprised saliva and gastric biopsies collected from each patient. Exclusion criteria were history of peptic ulcer, bleeding ulcer, cancer or recent use of antibiotics, proton pump inhibitors and non-steroidal anti-inflammatory drugs. Two sets of primers homologous to 534 bp fragment of H. pylori DNA, which have been shown previously to be highly specific and sensitive, were used for the polymerase chain reaction (PCR) amplification.

RESULTS

72 (90 percent) of the symptomatic group and 10 asymptomatic subjects were infected with H. pylori in the stomach as determined by histology and direct PCR amplification of biopsy DNA obtained from each subject. H. pylori DNA was identified in the saliva of 70 (87.5 percent) symptomatic subjects and 12 (60 percent) asymptomatic control subjects.

CONCLUSION

High rates of detection using saliva as a specimen indicate that saliva of the infected person could serve as a reliable non-invasive alternative to detect the presence of H. pylori infection in comparison to the currently available standard diagnostic tests.

Immune response to an indigenously developed r-Hepatitis B vaccine in mixed population: Study of an accelerated vaccination schedule

AIM: To establish the safety and efficacy of an indigenously developed r-hepatitis B vaccine using an accelerated schedule and to highlight the social awareness and commitment in preventing the spreading of hepatitis B virus infection.

METHODS: The study was a multicentric, double blind, randomized (3:1) study using three doses of vaccine immunization schedule (20 μg for those above 10 years old and 10 μg for those below 10 years old) on d 0, 30 and 60. One hundred and sixty-six subjects were enrolled (87 males and 76 females aged 5-35 years). The main outcome measure was assessment of immunogenicity and safety.

RESULTS: A 100% seroconversion response was observed on the 30^th d after the 1^st injection in both the experimental groups. The sero-protection data reported a 41.2-65.6% response on the 30^th d after the 1^st injection and reached 100% on the 60^th d. Descriptive statistical analysis showed a geometric mean titer value of 13.77 mIU/mL in the test (BEVAC) group and 10.95 mIU/mL in the commercial control (ENGERIX-B) group on the 30^th d after the 1^st injection. The response on the 60^th d showed a geometric mean titre value (GMT) of 519.84 mIU/mL in the BEVAC group and 475.46 mIU/mL in the ENGERIX-B group. On the 90^th d, the antibody titer response was observed to be 2627.58 mIU/mL in the BEVAC group and 2272.72 mIU/mL in the ENGERIX-B group. Two subjects in each group experienced pains at injection site after the first vaccination. A total of six subjects in both groups experienced a solicited adverse reaction, which included pains, swelling and redness at the injection site, three subjects in the group-B had a pain at the injection site after the third dose. No other serious adverse events occurred and no dose-related local or general symptoms were observed during the study.

CONCLUSION: The vaccine is safe, efficacious and immunogenic in comparison with the well documented ENGERIX-B.

The cag pathogenicity island of Helicobacter pylori is disrupted in the majority of patient isolates from different human populations

The cag pathogenicity island (cag-PAI) is one of the major virulence determinants of Helicobacter pylori. The chromosomal integrity of this island or the lack thereof is speculated to play an important role in the progress of the gastroduodenal pathology caused by H. pylori. We determined the integrity of the cag-PAI by using specific flanking and internally anchored PCR primers to know the biogeographical distribution of strains carrying fully integral cag-PAI with proinflammatory behavior in vivo. Genotypes based on eight selected loci were studied in 335 isolates obtained from eight different geographic regions. The cag-PAI appeared to be disrupted in the majority of patient isolates throughout the world. Conservation of cag-PAI was highest in Japanese isolates (57.1%). However, only 18.6% of the Peruvian and 12% of the Indian isolates carried an intact cag-PAI. The integrity of cag-PAI in European and African strains was minimal. All 10 strains from Costa Rica had rearrangements. Overall, a majority of the strains of East Asian ancestry were found to have intact cag-PAI compared to strains of other descent. We also found that the cagE and cagT genes were less often rearranged (18%) than the cagA gene (27%). We attempted to relate cag-PAI rearrangement patterns to disease outcome. Deletion frequencies of cagA, cagE, and cagT genes were higher in benign cases than in isolates from severe ulcers and gastric cancer. Conversely, the cagA promoter and the left end of the cag-PAI were frequently rearranged or deleted in isolates linked to severe pathology. Analysis of the cag-PAI genotypes with a different biogeoclimatic history will contribute to our understanding of the pathogen-host interaction in health and disease.

Comparison of biochemical and cytotoxic functions of hepatocytes from goat, pig and human fetuses

BACKGROUND AND AIM

To overcome the problem of shortage of donor organs, xenotransplantation of cells offers an alternative to orthotopic transplantation. Of the higher animals, the pig is considered as a suitable donor because of the similarity in size and function of pig organs to human organs. However, successful transplantation of pig organs/cells for human therapy is limited by hyperacute rejection, improper functioning of xenografts and the risk of transmission of endogenous retroviruses to the recipient. Thus, there is a pressing need to explore an alternate mammalian source to bridge the gap between the donor and the recipient waiting for transplantation. This has warranted us to explore the application of goat hepatocytes as a treatment modality in acute liver failure.

METHODS

In the present investigation, isolated goat hepatocytes were assessed for their viability, membrane integrity, synthetic and cytotoxic functions, and compared with the hepatocytes of pig and human fetuses (28-36 weeks).

RESULTS

The isolated hepatocytes from goat, pig and human fetuses were comparable in their viability, membrane integrity and synthetic functions. However, the cytotoxic functions assessed using 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay demonstrated a significant reduction in the viability of the pig hepatocytes (38%) as compared with the goat and human fetal hepatocytes, which retained their viability (98%) on incubation with normal human serum.

CONCLUSION

These observations are significant as they suggest that goat hepatocytes probably can be explored as a source for cell therapy in the treatment of acute liver failure.

Microevolution between paired antral and paired antrum and corpus Helicobacter pylori isolates recovered from individual patients

Sequence variations located at the signal sequence and mid-region within the vacA gene, the 3'-end of the cagA gene, the indel motifs at the 3'-end of the cag pathogenicity island and the regions upstream of the vacA and ribA genes were determined by PCR in 19 paired antral or antrum and corpus Helicobacter pylori isolates obtained at the same endoscopic session, and three antral pairs taken sequentially. Random amplification of polymorphic DNA (RAPD)-PCR and fluorescent amplified fragment length polymorphism (FAFLP)-PCR fingerprinting were applied to these paired clinical isolates. The FAFLP-PCR profiles generated were phylogenetically analysed. For the 22 paired isolates there were no differences within pairs at five of the genetic loci studied. However, six pairs of isolates (27%), of which four were antrum and corpus pairs, showed differences in the numbers of repeats located at the 3'-end of the cagA gene. RAPD-PCR fingerprinting showed that 16 (73%) pairs, nine of which were antrum and corpus pairs, possessed identical profiles, while six (27%) displayed distinctly different profiles, indicating mixed infections. Three of the six pairs showing differences at the 3'-end of the cagA gene yielded identical RAPD-PCR fingerprints. FAFLP-PCR fingerprinting and phylogenetic analysis revealed that all 16 pairs that displayed identical RAPD-PCR profiles had highly similar, but not identical, fingerprints, demonstrating that these pairs were ancestrally related but had undergone minor genomic alterations. Two antrum and corpus pairs of isolates, within the latter group, were isolates obtained from two siblings from the same family. This analysis demonstrated that each sibling was colonized by ancestrally related strains that exhibited differences in vacA genotype characteristics.

UV-B Induced stimulation of phosphatidylinositol 3-kinase in human fetal hepatocytes

We investigated the effect of UV-B irradiation on PI 3-kinase activity in human fetal hepatocytes. When cells were exposed to monochromatic (304nm) UV-B light, a significant increase in intracellular PI 3-kinase activity was observed in a dose dependent manner with maximal activity upon 1500 Jm(-2) irradiation. At 1500 Jm(-2) dose PI 3-kinse activity increased by 80% in membrane fraction of fetal hepatocytes of 25 weeks gestation. PI 3-kinse inhibitors wortmannin and LY294002 specifically inhibited the UV-B induced lipid kinase activity and blocked significantly the UV-B induced cell viability. The data suggests a correlation between cell survival and elevated levels of PI 3-kinase and suggest that UV-B irradiation at a dose of 1500 Jm(-2) is ideal for fetal hepatocyte transplantation. Also, PI 3-kinase levels could be a representative marker for viable UV-B irradiated fetal hepatocytes for transplantation.

Geographical difference in antimicrobial resistance pattern of Helicobacter pylori clinical isolates from Indian patients: Multicentric study

AIM

To assess the pattern of antimicrobial resistance of Helicobacter pylori isolates from peptic ulcer disease patients of Chandigarh, Delhi, Lucknow, Hyderabad and Chennai in India, and to recommend an updated anti-H. pylori treatment regimen to be used in these areas.

METHODS

Two hundred and fifty-nine H. pylori isolates from patients with peptic ulcer disease reporting for clinical management to the Post Graduate Institute of Medical Education and Research, Chandigarh; All India Institute of Medical Sciences, New Delhi; Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow; Deccan College of Medical Sciences and Allied Hospitals, Hyderabad; and hospitals in Chennai in collaboration with the Dr ALM Post Graduate Institute of Basic Medical Sciences were analyzed for their levels of antibiotic susceptibility to metronidazole, clarithromycin, amoxycillin, ciprofloxacin and tetracycline. The Epsilometer test (E-test), a quantitative disc diffusion antibiotic susceptibility testing method, was adopted in all the centers. The pattern of single and multiple resistance at the respective centers and at the national level were analyzed.

RESULTS

Overall H. pylori resistance rate was 77.9% to metronidazole, 44.7% to clarithromycin and 32.8% to amoxycillin. Multiple resistance was seen in 112/259 isolates (43.2%) and these were two/three and four drug resistance pattern to metronidazole, clarithromycin, amoxycillin observed (13.2, 32 and 2.56%, respectively). Metronidazole resistance was high in Lucknow, Chennai and Hyderabad (68, 88.2 and 100%, respectively) and moderate in Delhi (37.5%) and Chandigarh (38.2%). Ciprofloxacin and tetracycline resistance was the least, ranging from 1.0 to 4%.

CONCLUSION

In the Indian population, the prevalence of resistance of H. pylori is very high to metronidazole, moderate to clarithromycin and amoxycillin and low to ciprofloxacin and tetracycline. The rate of resistance was higher in southern India than in northern India. The E-test emerges as a reliable quantitative antibiotic susceptibility test. A change in antibiotic policy to provide scope for rotation of antibiotics in the treatment of H. pylori in India is a public health emergency.

Prevalence, risk factors and genotype distribution of HCV and HBV infection in the tribal population: a community based study in south India

Viral hepatitis caused by the hepatitis C virus (HCV) and hepatitis B virus (HBV) represents a major public health problem in India. These viruses share common modes of transmission, such as parenteral routes. We aimed to assess the exposure of a tribal population to these viruses in south India. The present study was carried out on serum samples from 890 individuals (526 males and 324 females) belonging to the Lambada tribe residing in the state of Andhra Pradesh, south India. Anti-HCV antibody and hepatitis B surface antigen (HBsAg) status in the sera were analyzed using commercially available enzyme immunoassays (Abbott Labs, Chicago, IL). HCV-RNA and HBV-DNA in the sera was tested by reverse transcriptase polymerase chain reaction (RT-PCR) and PCR, respectively. The infecting genotype of HCV was determined using type-specific primers corresponding to the NS5 region of the virus. Out of the 890 samples, 18 (2.02%; male 11/526; female 7/364) were positive for HCV-RNA by RT-PCR and, 17 of them were positive for anti-HCV antibody. Genotyping of HCV isolates from the 18 individuals positive for HCV-RNA revealed that 66.67% (12/18) were infected with type 1 of HCV and its variants; while in the remaining (6/18), the infecting genotype was found to be type 3 and its variants. A total of 46 samples (5.16%; males 28/526; female 18/364) were positive for HBsAg; while 11 were positive only for HBV-DNA, 9 were positive for both hepatitis B e antigen (HBeAg) and HBV-DNA. Cultural practices such as tattooing, traditional medicine (e.g. blood-letting), rituals (e.g. scarification), body-piercing etc are the potential sources of spread of infection in this tribe. None of the samples analyzed revealed co-infection with the 2 viruses.

Genetic fine structure analysis of Helicobacter pylori isolates before and after treatment

BACKGROUND

Eradication of H. pylori infection cures peptic ulcer disease and conversely, relapse is associated with reappearance of H. pylori infection. However, it is not clear whether the recurrence of ulcers following H. pylori eradication is due to recrudescence (identical strain) of the previous infection or as a result of exogenous reinfection (different strain) by another strain. The aim of the present study was to analyze the FAFLP patterns of pre and post treatment H. pylori samples to check if the recurrence was due to recrudescence or reinfection.

MATERIALS AND METHODS

24 of 30 duodenal ulcer (DU) subjects screened for H. pylori infection were positive for H. pylori infection. The treatment regime included pantoprazole, ciprofloxacin and amoxicillin. The patients were called for a repeat endoscopy after one month and screened for H. pylori infection. FAFLP analysis and PCR for the cagA and vacA gene was performed for the pre and post treatment samples.

RESULTS

Of the 24 positive H. pylori patients, only 6 were negative after treatment and the remaining 18 were positive for H. pylori infection. The analysis of the pre and post treatment samples of the 18 patients showed that the FAFLP profiles of the initial and follow-up pools were similar to one another.

CONCLUSION

It can be concluded that in the present series of patients, reinfection was due to recrudescence of infection due to incomplete eradication. The study also suggests that DNA fingerprinting by FAFLP provides discriminatory and complementary data for identifying strains of H. pylori while monitoring therapy.

Predominance of antibodies to hepatitis C virus envelope proteins in various disease statuses of hepatitis C

The antibody profile to various proteins of hepatitis C virus (HCV) was studied in 113 patients positive for HCV RNA in various disease statuses of hepatitis C (HC). A single peptide (E2/NS1, aa 413-436 of HCV polyprotein) chosen from a conserved region at the C-terminus of the hypervariable region (HVR) HVR1 of HCV was found to be sufficient for reliable diagnosis of the infection, even in the acute phase. Six hundred and one suspected HC cases and 200 voluntary blood donors were tested by this peptide. The sensitivity of detection of HCV antibodies by this peptide did not increase with addition of peptides from other HCV proteins. Our results clearly demonstrate that antibodies to HCV envelope proteins occur in a higher percentage of the infected population than those to other proteins. This emphasizes the necessity of using representative sequences from HCV envelope proteins in diagnostic immunoassays of this viral infection.

The effect of the anti-allergic agent avil on abnormal scar fibroblasts

Abnormal wound healing in humans leads to the formation of hypertrophic scar and keloids. These abnormal scars accumulate excessive extracellular matrix proteins through increased synthesis as well as decreased degradation. In order to find a therapeutic control for scar formation, we investigated the effect of avil (pheniramine maleate) on fibroblasts cultured from abnormal scars in comparison to normal skin. We observed a decrease in the proliferation rate in cells from normal skin (39%), hypertrophic scar (44%), keloid (63%) and in DNA synthesis in cells from normal skin (50%), hypertrophic scar (55%) and keloid (63%) treated with 8 mM avil (72 h). The rate of decrease in collagen synthesis in normal skin (44%), hypertrophic scar (74%) and keloid fibroblast (73%) correlated with changes in DNA synthesis.

In vivo identification, survival, and functional efficacy of transplanted hepatocytes in acute liver failure mice model by FISH using Y-chromosome probe

Hepatocyte transplantation has excited much interest in lending temporary metabolic support to a failing liver following acute liver injury. The exact site from which they act and the clinical, biochemical, and histological changes in the recipient body following hepatocyte transplantation is yet to be worked out. The present study is an attempt to delineate location and function of transplanted hepatocytes and also the overall survival of these cells with a fluorescent in situ hybridization (FISH) technique using a Y-chromosome-specific probe in a carbon tetrachloride (CCl4)-induced mice model of fulminant hepatic failure. Fifty-five syngenic adult Swiss female mice of approximately the same age and body weight were divided into three groups. Group-1 (n = 15), which received mineral oil, served as a negative control. Group-II (n = 15) received CCl4 (3 mL/kg) 40% vol/vol in mineral oil, by gavage served as positive control for hepatic failure. Group-III (n = 25) received intrasplenic transplantation of syngenic single cell suspension of hepatocytes in Hanks medium, after 30 h of CCl4 administration. Male Swiss adult mice (n = 15) served as donors of hepatocytes. The overall survival of animals in groups I to III was 100, 0, and 70%, respectively, by 2 wk of the study period. Transplanted hepatocytes were identified by Periodic Acid Schiff (PAS) staining and confirmed with a FISH technique using the Y-chromosome probe. The majority of exogenously transplanted hepatocytes were found in the liver and spleen sections even after 1 wk of hepatocyte transplantation. Transplanted cells were mostly found to be translocated into the sinusoids of the liver. Transplanted hepatocytes were found to be beneficial as a temporary liver support in a failing liver, significantly improving the survival of the animals. In the present study, the FISH technique was used to unequivocally distinguish the transplanted cells from the host, and thus describes a model for studying the distribution and survival of the transplanted cells.

Non-viral ex vivo hepatic gene transfer by in situ lipofection of liver and intraperitoneal transplantation of hepatocytes

Perfusion of liver with plasmid DNA-lipofectin complexes via the portal vein results in efficient accumulation of the vector in hepatocytes. Such hepatocytes, when administered intraperitoneally into a hepatectomized rat, repopulate the liver and express the transgene efficiently. This procedure obviates the need for large-scale hepatocyte culture for ex vivo gene transfer. Further, intraperitoneal transplantation is a simple and cost-effective strategy of introducing genetically modified hepatocytes into liver. Thus, in situ lipofection of liver and intraperitoneal transfer of hepatocytes can be developed into a novel method of non-viral ex vivo gene transfer technique that has applications in the treatment of metabolic disorders of liver and hepatic gene therapy.

Roxatidine in duodenal ulcer

Roxatidine acetate is a new H2-receptor antagonist. A randomized double-blind clinical trial in fifty-three patients with endoscopically proven duodenal ulcers > 5 mm in diameter was undertaken to compare safety and efficacy of roxatidine with that of ranitidine. Twenty-six patients received roxatidine (75 mg bid) while 27 patients received ranitidine (150 mg bid) for 4 weeks. One patient in each group did not come for follow up. Roxatidine and ranitidine had comparable ulcer healing rates (22/25 vs 22/26); roxatidine, however, resulted in greater reduction in the number and severity of night time pain episodes (p < 0.05). No adverse event was reported during 4 weeks of treatment with roxatidine. Thus roxatidine achieves the primary therapeutic goal of relief of pain better than ranitidine.

Effect of UV-B (302 nm) irradiation on isolated rat hepatocytes

The present study aimed to evaluate the effect of UV-B irradiation on the functional integrity, and the metabolic and detoxifying capacity of isolated rat hepatocytes. Isolated rat hepatocytes were irradiated in various doses (400 Jm-2, 600 Jm-2, 800 Jm-2 and 1000 Jm-2). The cells were assayed for total lactate dehydrogenase, Na(+)-K(+)-ATPase, ornithine carbamyltransferase activity (OCT) and urea production capacity. Lactate dehydrogenase and Na(+)-K(+)-ATPase activity were significantly decreased in all four irradiated groups (P < 0.001), whereas viability, OCT and urea production capacity showed no alterations.