Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The review reflects the concerns of researchers of the "Stefan S. Nicolau" Institute of Virology who used electron microscopy techniques with a view to visualizing morphological features of virus structure (influenza, adeno, hepatitis, herpes, cytomegalic, Aujeszky, rabies viruses, etc.) and different aspects of the virus - host cell relationships (Sendai virus/Hep2 cells, influenza and adenovirus/mouse lung, subacute sclerosing panencephalitis/human brain or cell cultures, Coxsackie and foot-and-mouth disease virus/myofibrils, Rubarth hepatitis virus/chick embryo liver cells, a.o.). Morphological aspects of normal or tumoral cells and the influence of chemical agents (actinomycin D, EDTA), viruses, bacteria or parasites have also been studied. Mention is made of several original techniques used to obtain electron microscopy preparations.
 ...
PMID:Contribution of the "Stefan S. Nicolau" Institute of Virology to the electron microscopic study of viruses. 639 66

Alpha 1-protease inhibitor (alpha 1 PI), also called alpha 1-antitrypsin, may be useful for replacement therapy in a number of chronic or acute disorders. The risk associated with the possible presence of hepatitis virus can be greatly reduced by pasteurization at 60 degrees C for 10 h. A series of thermal denaturation profiles was obtained in the presence of various protein stabilizers using the increase in 1,8-anilinonaphthalene sulfonate fluorescence that accompanies protein denaturation. A parallel series of experiments was conducted to evaluate each additive for its capacity to protect the biological activity of alpha 1 PI. As much as 92% of the inhibitory activity against elastase and trypsin could be recovered after pasteurization in buffer containing citrate (1.2 M) and either EDTA (0.5 M) or gluconate (1.2 M). Loss of activity was not affected by protein concentration. In conclusion, conditions have been developed to protect the bulk of alpha 1 PI from denaturation during pasteurization, and this should give an added impetus to efforts to test the efficacy of this protein in various clinical conditions.
 ...
PMID:Thermal denaturation of alpha 1-protease inhibitor. Stabilization by neutral salts and sugars. 640 63

This study was undertaken to produce experimental autoimmune hepatitis in mice, and to examine the role of liver specific lipoprotein (LSP), if any, and of cellular immunity in such a model. After immunization of three strains of mice (C57BL/6, C3H/He and BALB/c) with syngeneic crude liver proteins, most prominent liver changes histologically mimicking human hepatitis were produced in the liver of C57BL/6 (B6) mice. Antigenic and immunogenic activity of LSP in the crude liver proteins was decreased by the treatment of freezing and thawing, and the recovery of the antigenic activity seemed to correlate with the susceptibility of immunized mice to the induction of liver damage. Autoantibody against LSP was demonstrated in the serum of immunized B6 mice, but not in the sera of other strains after immunization. It was also found that EDTA contained in the buffer used for purification of LSP distinctly suppressed lymphocyte activity in vivo and in vitro. With the use of EDTA free LSP, it was shown that spleen cells of immunized B6 mice (especially of T cell enriched fraction) had a high reactivity studied by lymphocyte transformation test. Further examination showed that EDTA free LSP could induce mild liver lesions and lymphocyte reactivity against LSP, although neither histological change nor lymphocyte reactivity was found in the liver of B6 mice immunized with EDTA containing LSP.
 ...
PMID:Study of cellular immunity in experimental autoimmune hepatitis in mice. 643 Jun 15

The authors report the case of a 51-year-old woman who developed cholestatic and cytolytic hepatitis after an overdose of sodium aurothiopropanol sulfonate 1.1 g, namely 300 mg gold metal. Liver biopsy demonstrated cholestasis, centrolobular steatosis and portal fibrosis. Electron microscopy showed abundant lipo-pigments in the hepatic and cellular cells, as well as myelinic bodies. Gold analysis by atomic absorption spectroscopy showed a level of 22.76 micrograms per ml in the plasma and a level of 2.16 micrograms per g in the liver. Chelating agents increased the urinary gold excretion, but were without effect on the course of hepatitis. Dimercaptopropanol seemed to favor the occurrence of other gold salt side-effects and penicillamine increased the hepatic cytolysis. The patient recovered without sequelae.
 ...
PMID:[Hepatitis secondary to a gold salt overdose]. 648 87

These studies describe an assay of whole blood clot lysis as measured by release of 125I-fibrinogen degradation products. Optimal rates of lysis were obtained at 37 degrees C in 10-12 mM EDTA or 3,8% citrate and 4 u of thrombin/ml. Eighteen normal subjects and eight patients (six with recurrent deep vein thrombosis, one with thrombasthenia, and one with hepatitis and resolving portal vein thrombosis) were studied using this assay. The clots of seventeen of the eighteen normal subjects were 50% lysed at 40 hours. The clots of the patients with venous thrombosis and thrombasthenia did not lyse whereas the clots of the patient with hepatitis, resolving portal vein thrombosis and a high plasminogen activator level (0.32 CTA units) were 100% lysed at 4.5 hrs.
 ...
PMID:Observations on optimal conditions for lysis of whole blood clots and use of this assay as a screening assay in clinical investigation. 682 Jan 94

Antithrombin III is of potential value for replacement therapy in patients with acquired or congenital deficiencies. Pasteurization of the purified inhibitor for 10 h at 60 degrees C can reduce the risk of transfusion hepatitis. Addition of appropriate stabilizers can largely prevent the loss of antithrombin activity which otherwise occurs during pasteurization. Studies of the mechanism of denaturation and stabilization have been facilitated by the use of 8-anilino-1-naphthalene sulfonate which binds weakly to the inhibitor and whose fluorescence undergoes a sigmoidal response to increasing temperature. The extent of the increase in 8-anilino-1-naphthalene sulfonate fluorescence correlates roughly with the loss of antithrombin activity and with the extent of protein aggregation as determined by high pressure liquid chromatography. The midpoint, Td, of the thermal denaturation curve increases by 13 degrees C and 19 degrees C in the presence of 0.5 M and 1.0 M sodium citrate, respectively. Phosphate, sulfate, and EDTA are also strong stabilizers while the chaotropic anions, iodide and thiocyanate are potent destabilizers. Heparin at 10 mg/ml increases Td by 7 degrees C, presumably through a direct binding mechanism; chondroitin sulfate and hyaluronic acid have no effect. Samples pasteurized for 10 h at 60 degrees C in the presence of 0.5 M and 1.0 M citrate retain essentially full activity but exhibit evidence of minor alterations in their interaction with heparin.
 ...
PMID:Thermal denaturation of antithrombin III. Stabilization by heparin and lyotropic anions. 729 49

Viroids and other circular subviral RNA pathogens, such as the hepatitis delta agent, use a rolling circle replication cycle requiring an intact circular RNA. However, many infectious RNAs have the potential to form self-cleavage structures, whose formation must be controlled in order to preserve the circular replication template. The native structure of delta RNA contains a highly conserved element of local tertiary structure which is composed of sequences partially overlapping those needed to form the self-cleavage motif. A bimolecular complex containing the tertiary structure can be made. We show that when it is part of this bimolecular complex the potential cleavage site is protected and is not cleaved by the delta ribozyme, demonstrating that the element of local tertiary structure can function as a ribozyme control element in vitro. Physical studies of the complex containing this element were carried out. The complex binds magnesium ions and is not readily dissociated by EDTA under the conditions tested; > 50% of the complexes remain following incubation in 1 mM EDTA at 60 degrees C for 81 min. The thermal stability of the complex is reduced in the presence of sodium ions. A DNA complex and a perfect RNA duplex studied in parallel showed a similar effect, but of lesser magnitude. The RNA complex melts at temperatures approximately 10 degrees C lower in buffers containing 0.5 mM MgCl2 and 100 mM NaCl than in buffers containing 0.5 mM MgCl2 with no NaCl (78.1 compared with 87.7 degrees C). The element of local tertiary structure in delta genomic RNA appears to be a molecular clamp whose stability is highly sensitive to ion concentration in the physiological range.
 ...
PMID:Tm studies of a tertiary structure from the human hepatitis delta agent which functions in vitro as a ribozyme control element. 750 61

Amplification by the polymerase chain reaction (PCR) of hepatitis B virus (HBV) DNA extracted from parallel samples of serum and heparinized plasma gave contradictory results, indicating that heparin inhibits virus detection. Similarly, analysis of PCR products of woodchuck hepatitis virus (WHV) DNA showed that heparinization of blood abolished WHV DNA amplification, while anticoagulation with sodium EDTA or acid citrate dextrose did not. Amplification of recombinant WHV and HBV DNA in the presence of increasing concentrations of sodium heparin progressively inhibited and finally abolished virus genome detection. The inhibitory effect of heparin was reversed by treatment of either plasma or isolated DNA with heparinase (5 U/reaction, 1 h at 28 degrees C) prior to PCR. In contrast, heparin did not influence the detection of hepadnavirus in peripheral blood mononuclear cells (PBMC), even after prolonged incubation of the cells with heparin in culture. These findings confirm that heparin exerts a dramatic inhibitory effect on hepadnaviral DNA detection by PCR and they demonstrate that this effect can be reversed by heparinase. The findings also show that extensively washed PBMC derived from heparinized blood can be a reliable source of nucleic acids for amplification of hepadnavirus genome. These results imply that previous data should be reassessed if samples of heparinized plasma were found hepadnavirus DNA nonreactive by PCR or when these samples were used as a starting material for PCR quantitation of viral genome.
 ...
PMID:Detection of hepatitis B and woodchuck hepatitis viral DNA in plasma and mononuclear cells from heparinized blood by the polymerase chain reaction. 773 48

Genomic RNA of the hepatitis delta agent has a highly conserved element of local tertiary structure. This element contains two nucleotides which become covalently crosslinked to each other upon irradiation with UV light. Using direct RNA analysis, we now identify the two nucleotides as U-712 and U-865 and show that the UV-induced crosslink can be broken by re-exposure to a 254 nm peak UV light source. In the rod-like secondary structural model of delta RNA, nucleotides U-712 and U-865 are off-set from each other by 5-6 bases, a distance too great to permit crosslinking. This model needs to be modified. Our data indicate that bases U-712 and U-865 closely approximate each other and suggest that the smooth helical contour proposed for delta RNA is interrupted by the UV-sensitive element. The nucleotide sequence shows that the UV-sensitive site does not have a particularly high density of conventional Watson-Crick base pairs compared to the rest of the genome. However, this element may have a number of non-Watson-Crick bonds which confer stability. Following UV-crosslinking and digestion with 1 mg/ml of RNase T1 at 37 degrees C for 45 min in 10 mM Tris-HCl, 1 mM EDTA (conditions expected to give complete digestion), this element can be isolated as part of a 54 nucleotide long partial digestion product containing at least 16 internal G residues. UV-crosslinking analysis shows that this unusual tertiary structural element can form in a bimolecular complex.
 ...
PMID:An RNA tertiary structure of the hepatitis delta agent contains UV-sensitive bases U-712 and U-865 and can form in a bimolecular complex. 788 46

The levels of incorporated exogenous [3H]thymidine of peripheral blood mononuclear cells (PBMC) of the woodchuck were low after stimulation with mitogens concanavalin A (ConA), phytohemagglutinin (PHA), and pokeweed mitogen (PWM) when compared with other cell systems. The use of EDTA as an anticoagulant for blood sampling and AIM-V medium for culturing of PBMC improved the [3H]thymidine uptake of PBMC. A pronounced uptake is observed after use of [3H]adenine instead of [3H]thymidine for PBMC proliferation measurement. One likely explanation for the difference in [3H]adenine versus [3H]thymidine uptake is that the alternative pathway for thymidine monophosphate synthesis is important: the conversion of uridine to uridine monophosphate and, thereafter, to thymidine monophosphate. The optimal conditions for mitogen-induced proliferation of PBMC of the woodchuck were 2 micrograms/ml ConA and PHA at day 4 and 0.14 micrograms of PWM/ml at day 5. No consistent differences of [3H]adenine uptake were observed between PBMC from four woodchuck hepatitis virus-infected woodchucks and five uninfected animals.
 ...
PMID:Assessment of peripheral blood mononuclear cell proliferation by [2-3H]adenine uptake in the woodchuck model. 860 97


<< Previous 1 2 3 Next >>