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H Jauregui

Publications and source records attributed to H Jauregui.

12 recordsLinked to original sources
PubMed2001

Hepatocyte-based gene therapy.

Hepatocyte-based gene therapy may be used to replace a missing gene product, confer proliferating ability to cultured hepatocytes, prevent allograft rejection, massively repopulate the host liver, or grow xenogeneic hepatocytes in mammalian liver. Gene transfer into isolated hepatocytes can be accomplished via nonviral or viral vectors, the viral vectors being more useful at this time. Common recombinant viruses that integrate into the host genome include murine leukemia retroviruses and lentiviruses, adenoassociated virus, and the T-antigen-deleted SV40 virus. Episomal viruses, such as adenoviruses, permit efficient gene transfer, but the transgene is lost upon proliferation of the transplanted hepatocyte in the host. Hybrid viruses that combine the high transduction efficiency of adenoviral vectors and the integrative capacity of other vectors, such as adenoassociated viruses, have been designed. Massive repopulation of the liver by transplanted hepatocytes can be achieved if a mitotic stimulus to the transplanted cells is combined with prevention of proliferation of the host hepatocytes. Treatment with a plant alkaloid or retrorsine, or preparative irradiation of the liver can be used to inhibit host hepatocellular proliferation, while partial hepatectomy, expression of Fas ligand, or thyroid hormone administration can be used as a mitotic stimulus to the transplanted cells.

Adenoviridae↗
PubMed2001

Profiling the adult human liver transcriptome: analysis by cDNA array hybridization.

BACKGROUND/AIMS: A comprehensive profile of genes expressed at the mRNA level (transcriptome) in human liver tissue is important for elucidating the pathogenesis and treatment of hepatic diseases. The recent development of cDNA array hybridization allows the parallel monitoring of thousands of genes expressed in a single organ. METHODS: High-density microarrays containing 4043 known and unique human cDNA gene targets were used to quantitatively analyze the expression of genes in human livers. Expressed gene transcripts were classified by function and listed with information of their chromosomal positions. Computational analysis was used to cluster genes according to similarity in pattern of gene expression. RESULTS: A total of 2418 unique gene transcripts were detected in five liver specimens. Through relational database analysis, we determined 1212 genes that were commonly expressed in 4 of the five liver specimens. Furthermore, analysis of the total 2418 expressed genes by self-organizing maps and hierarchical clustering unexpectedly revealed a genomic acute phase response in two of the liver specimens. CONCLUSIONS: These findings represent a comprehensive preliminary molecular index of genes transcribed in the adult human liver. The information may serve as a resource for speeding up the discovery of genes underlying human hepatic diseases.

Adult↗
PubMed1996

Flow cytometric characterization of isolated porcine hepatocyte suspensions for liver support.

The high yield hepatocyte isolation necessary for hybrid liver assist devices (LAD) unavoidably increases contamination by nonparenchymal cells and depresses hepatocyte viability and functions. We have developed a flow cytometric procedure that improves quality control of the isolations. Cells present in these preparations were labeled by immunofluorescent antibody staining against cytokeratin 8, 18 as well as vimentin to identify hepatocytes, fibroblasts, and endothelial cells. Antibody staining against albumin and carbamoylphosphate synthetase allowed assessment of levels of albumin and carbamoylphosphate synthetase based on the hepatocyte relative fluorescence intensity. Hepatocyte P450 enzyme activity was measured by its ability to convert 5,6-methoxycarbonylfluorescein, a nonfluorescent substrate, to an intracellular fluorescent product. Flow cytometric methods of cell type identification and cell function assessment are fast and accurate and can be applied to commercial cell production. They may also provide an avenue for the enrichment of otherwise heterogeneous hepatocyte suspensions with cells presenting the specific functions desired for an hybrid liver assist devices.

Animals↗
PubMed1992

Influence of different substrates in detoxification activity of adult rat hepatocytes in long-term culture: implications for transplantation.

Substrates used to immobilize hepatocytes for transplantation govern attachment and long-term metabolic activity of these cells. The choice of these substrates is based on the familiarity with proteinaceous materials that are constituents of the extracellular matrix. The use of substrates that recognize carbohydrates on the cell surface may provide an alternative method to attach adult mammalian hepatocytes. In this study, immobilized lectins on tissue culture plasticware were used to support hepatocyte attachment. Long-term cultures with these substrates were compared with control cultures seeded on a mixture of collagen types I and III (Vitrogen). To evaluate the attachment efficiency and long-term maintenance of diazepam metabolic activity of hepatocytes seeded on different commercially available plasticware, four different types of polymers (supplied as 60-mm dishes) were tested. Diazepam, a benzodiazepine metabolized by the P450 intracytoplasmic pathway, is associated with a synaptic receptor (GABA-benzodiazepine receptor) which plays an important role in hepatic coma. Polymethylpentene, a derivative of polypropylene treated by plasma discharge, was the best polymer to maintain P450 phenotypic expression, although other polymers provided similar cell attachment efficiencies. The amounts of adsorbed concanavalin A, Arachis hypogaea (peanut), Lens culinaris, and Pisum sativum agglutinin correlate with the percentage values of hepatocyte attachment. Cell attachment to wheat germ agglutinin increased with increased lectin concentrations in spite of constant amounts of adsorbed lectin, whereas hepatocyte attachment to Bandieraea simplicifolia agglutinin was lower and did not change at different lectin concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1981

Granulomas in primary biliary cirrhosis: a prognostic feature.

To evaluate the significance of granulomas in primary biliary cirrhosis, 295 liver biopsy specimens from 100 patients with primary biliary cirrhosis were reviewed. Granulomas were found in specimens from 54 patients and were less frequent as histologic stage increased. They often persisted in multiple specimens from individual patients. Granulomas did not correlate with clinical presentation or biochemical values, but were associated with better survival since of the 18 patients who died, only 2 showed granulomas on biopsy. To test this finding in patients at a uniform stage of progression, patients with late primary biliary cirrhosis were evaluated separately. Patients with and without granulomas were closely matched in clinical, laboratory, and histologic features. Although 23 of these 57 patients showed granulomas, they were present in only 1 of 14 patients who died. Thus, the presence of granulomas in primary biliary cirrhosis seems to be of prognostic significance, independent of previously reported prognostic indicators.

Adult↗
PubMed1979

Characterization and quantitation of murine-delayed hypersensitivity responses elicted with particle-associated human gamma-globulin.

Parameters delineating the utilization of particle-associated human gamma-globulin to quantitate murine-delayed hypersensitivity (DHS) responses include: (1) the conditions used to prepare HGG-coated polystyrene latex particles; (2) the marked increase in sensitivity of detection of delayed immune responsiveness using particle-bound HGG; (3) a histologic analysis of the lesions induced by HGG-latex in DHS mice, and (4) the increased retention of particle-associated as opposed to soluble HGG at the site of challenge. The potential utilization of particle-bound antigens as a sensitive method of assessing the role of delayed-type responsiveness in tumor and transplantation immunity is discussed.

Animals↗
PubMed1978

Complications of wedge hepatic venography.

During wedge hepatic venography, mechanical injection should be accomplished at the lowest possible rate in order to avoid hemorrhagic infarction. Small amounts of contrast material should be administered. Hepatic angiography may result in an area of tumor blush at the site of a previous wedge injection.

Animals↗
PubMed1978

Selective transcatheter embolization of the upper gastrointestinal tract: an experimental study.

Transcatheter gastric embolization using Ivalon shavings was performed on three groups of dogs. The left gastric artery and splenic branches (the short gastric and left gastroepiploic arteries) were embolized in Group I, the left gastric artery in Group II, and the splenic branches in Group III. Infarctions of the gastric mucosa occurred only in Group I. Ischemic ulcers developed in three of the five dogs in Group I and in one of the three dogs in Group II. The study suggest that embolization can only be performed safety if particles of 0.3 mm or larger are used.

Animals↗
PubMed1978

Bleeding from cecal ulcers in renal transplant patients.

Cecal ulcerations represent a high percentage of causes of gastrointestinal bleeding in renal transplant patients. A close association of these lesions with cytomegalovirus (CMV) infection has been found, even though a cause-effect relationship has not been established. All of these patients are usually critically ill, and a progressive deterioration leading to death is the rule. Our experience suggests that the decrease of immunosuppressive drug therapy, followed by the nephrectomy of the transplanted kidney if signs of rejection are present, and right hemicolectomy are the best therapy. Angiographic procedures are of importance to determine the site of bleeding, stabilize the bleeding with the use of vasoconstrictor drug therapy, and to plan the surgical treatment.

Adult↗