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1.
Arch Microbiol ; 201(7): 951-967, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31025055

ABSTRACT

With the advent of new molecular tools, new taxa of sulphur-oxidising bacteria (SOB) in diverse environments are being discovered. However, there is a significant gap of knowledge about the ecology and diversity of SOB in thermal springs. Here, the species diversity and phylogenetic affiliations of SOB were investigated using 16S rRNA and functional gene marker, soxB in thermal springs of Thane district of Maharashtra, India. Most SOB detected by 16S rDNA sequences belong to different operational taxonomic units (OTU's): Firmicutes, α-, ß-, γ-Proteobacteria and Actinobacteria with the dominance of first class. However, the soxB gene clone library sequences had shown affiliation with the ß-, γ- and α-Proteobacteria. ß-Proteobacteria-related sequences were dominant, with 53.3% clones belonging to genus Hydrogenophaga. The thiosulphate oxidation assay carried out for different isolates having distinct identity showed the mean sulphate-sulphur production from 117.86 ± 0.50 to 218.82 ± 2.56 mg SO4-S l-1 after 9 days of incubation. Also, sulphur oxidation by the genus Nitratireductor, Caldimonas, Geobacillus, Paenibacillus, Brevibacillus, Tristrella and Chelatococcus has been reported for the first time that reveals ecological widening over which thiotrophs are distributed.


Subject(s)
Bacteria/classification , Bacteria/genetics , Biodiversity , Genetic Markers/genetics , Hot Springs/microbiology , RNA, Ribosomal, 16S/genetics , Actinobacteria/genetics , Betaproteobacteria/genetics , DNA, Bacterial/genetics , Gammaproteobacteria/genetics , India , Oxidation-Reduction , Phylogeny , Sulfur/metabolism
2.
Indian J Exp Biol ; 54(12): 801-7, 2016 12.
Article in English | MEDLINE | ID: mdl-30179427

ABSTRACT

Traditionally, the Indian Blackberry or locally called Jamun, Eugenia jambolana Lam. (Syn.: Syzygium cumini), is well known for its pharmacological potential, particularly anti-inflammatory. Here, we studied kaempferol-7-O-α-L-rhamnopyranoside]-4'-O-4'- [kaempferol-7-O-α-L-rhamnopyranoside (EJ-01) isolated from the E. jambolana leaves for possible anti-inflammatory activity. EJ-01 (3, 10 and 30 mg/kg, p.o.) was assessed for anti-inflammatory activity using carrageenan-induced paw edema model in mice by determining edema volume, myeloperoxidase (MPO), nitrite plus nitrate (NOx) and cytokine levels in paw edema tissue. EJ-01 significantly attenuated the edema, MPO levels, tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß) levels in the edema of paw at the 5th hour after carrageenan injection at all doses. EJ-01 (30 mg/kg) decreased the nitric oxide (NO) levels of the edema of paw at the 5th hour after carrageenan injection. The anti-inflammatory mechanisms of EJ-01 might be related to the decrease in the level of edema paw by reduced activities of NO and MPO. It probably exerts anti-inflammatory effects through the suppression of TNF-α and IL-1ß. Therefore, we conclude that EJ-01 could be positively exploited for itspotential benefits against inflammatory diseases and support the pharmacological basis of E. jambolana as traditional herbal medicine for the treatment of inflammatory diseases.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Flavonoids/pharmacology , Plant Extracts/pharmacology , Plant Leaves , Syzygium/chemistry , Animals , Carrageenan , Edema , Mice , Tumor Necrosis Factor-alpha
3.
Indian J Nephrol ; 25(4): 248-50, 2015.
Article in English | MEDLINE | ID: mdl-26199479

ABSTRACT

Immunoglobulin A (Ig A) nephropathy is the most common form of primary glomerulonephritis. The association of Ig A nephropathy with Grave's disease has not been reported so far. We report a case of 20-year-old female with Grave's disease who presented with edema, facial puffiness, and decreased urine output. She was found to be hypertensive with renal failure and nephrotic range proteinuria. Renal biopsy revealed features of Ig A nephropathy. The patient was treated with oral corticosteroids (1 mg/kg/day). To our knowledge, this is the first case showing association of Grave's disease with Ig A nephropathy.

4.
Musculoskelet Surg ; 99(2): 139-47, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25503441

ABSTRACT

PURPOSE: Fractures involving the femur in older adults are reasonably common. The aim of this study was to evaluate the results of MIPO technique using locking plates in geriatric patients for distal extra-articular femur fractures. METHODS: About 25 consecutive patients with distal extra-articular femur fractures aged 60 years and above were treated using locking plates and minimally invasive technique. Patients were studied prospectively over a period of 3 years. Parameters studied included patient demographics, fracture type, time taken for the surgery, time to union and any complications. RESULTS: Mean age of patients was 66.5 years. Nineteen (76%) patients were females. Most of fractures in our study were type 33A2 fractures (64%). Average time to full weight bearing was 14.32 weeks, and fractures united at an average of 16.88 weeks. There were two (8%) patients with superficial infection, two (8%) with implant tenderness. One (4%) patient developed knee stiffness. Five (20%) patients had extension lag of average 5°. One (4%) patient sustained a peri-implant fracture at 2 months. None of the patients developed non-union or delayed union. According to criteria laid by Schatzker's and Lambert, excellent results were achieved in 22 (88%) patients. CONCLUSIONS: Outcome of minimally invasive fixation of distal extra-articular femur fractures with locking plates in patients of age 60 years and above seems to be good with high union rate despite high prevalence of osteoporosis and comminution.


Subject(s)
Bone Plates , Femoral Fractures/surgery , Fracture Fixation, Internal/methods , Aged , Bone Screws , Female , Femoral Fractures/diagnostic imaging , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/instrumentation , Humans , Male , Middle Aged , Operative Time , Radiography
5.
Indian J Nephrol ; 23(6): 444-7, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24339524

ABSTRACT

Emphysematous pyelonephritis is a life-threatening condition characterized by necrotising gas forming infection of the renal parenchyma. We describe eight patients seen over a period of 2 years, 62.5% males and 37.5% females with age range between 21 and 65 years. About 75% patients had diabetes mellitus. Six patients were managed conservatively. One patient required nephrectomy with percutaneous drainage and one patient died without surgical intervention.

6.
Singapore Med J ; 47(12): 1044-8, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17139400

ABSTRACT

INTRODUCTION: The duration of human pregnancy is arbitrarily taken as 280 days (40 weeks). Foetuses are considered to be at high risk once pregnancy goes beyond the expected date of confinement. This study was carried out with the aim of determining the mean gestation age of low-risk pregnancies that went into spontaneous labour and the incidence of adverse outcomes in relation to gestation. METHODS: Low-risk singleton pregnancies admitted in spontaneous labour at a single community hospital in the Udupi district of Karnataka in South India, from December 2002 to December 2003, were analysed for mean gestational age at the onset of spontaneous labour and rates of perinatal complications by gestational age. RESULTS: Among the 1,094 women who went into spontaneous labour, the mean gestational age was 272.1 +/- 9 days. A significantly increased incidence of meconium-stained amniotic fluid beyond 39 weeks of gestation was observed. 783 of 1,094 women (80 percent) had delivered during the period of 261-280 days of pregnancy (period of one standard deviation around the mean gestational age at delivery). There was significant increase in perinatal morbidity indicators and mortality rates once the pregnancy carried beyond 280 days. CONCLUSION: Mean gestational age at the onset of labour for women native to the area of study was 272 days (standard deviation 9 days). Pregnancies beyond a duration of 280 days showed significantly increased perinatal morbidity. It is suggested that there is a need for determining the length of gestation and to compile gestation-wise incidence of meconium-stained amniotic fluid as an indicator of foetal maturity or the undisclosed risk factor, in addition to other neonatal morbidity indicators for different populations.


Subject(s)
Gestational Age , Labor, Obstetric/physiology , Pregnancy , Adolescent , Adult , Female , Humans , India , Pregnancy Outcome , Prospective Studies , Reference Values
7.
Mol Cell Endocrinol ; 247(1-2): 116-26, 2006 Mar 09.
Article in English | MEDLINE | ID: mdl-16442706

ABSTRACT

Transcriptional regulation by progesterone is mediated primarily through the two progesterone receptor (PR) isoforms, PR-A and PR-B. Primary human endometrial stromal cell cultures, in which endogenous PR expression was lost, were infected with adenovirus expressing PR-A, PR-B, or both. Global gene expression analysis was conducted on vehicle and 30 nM progesterone (P4) treated cells following 12 h treatment. Interestingly, many genes regulated by PR-B alone or upon PR-A and PR-B co-expression, did not overlap with each other or with the PR-A expression group. Although many genes known to be progestin regulated in the uterus in vivo were also regulated in this study, markedly little overlap with published P4 regulated genes from human breast cancer cells was observed. Progesterone dose response curves were generated for several genes demonstrating gene selective potency and efficacy for each PR isoform. Furthermore, the PR isoforms opposed each other in regulation of tissue factor, with PR-B increasing and PR-A decreasing both mRNA and protein levels. Our data provide a view of global gene expression by PR isoforms in human endometrial cells and a comparison with other cell types. The specific genes and regulation patterns found provide groundwork to revealing the mechanism of PR isoform selectivity, and perhaps ultimately to the tissue selective properties these receptors appear to exhibit.


Subject(s)
Endometrium/metabolism , Receptors, Progesterone/genetics , Cells, Cultured , Endometrium/cytology , Endometrium/drug effects , Female , Gene Expression Profiling , Gene Expression Regulation , Humans , Oligonucleotide Array Sequence Analysis , Progesterone/pharmacology , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/metabolism , Receptors, Progesterone/metabolism , Stromal Cells/drug effects , Stromal Cells/metabolism
8.
Vaccine ; 17(9-10): 1035-41, 1999 Mar 05.
Article in English | MEDLINE | ID: mdl-10195612

ABSTRACT

The currently marketed hepatitis B vaccines in the U.S. are based on the recombinant major hepatitis B surface antigen (HBsAg) of hepatitis B virus. Although a large majority of individuals develop protective immunity to HBV-induced disease after three immunizations, routinely a small but a significant percentage of the human population does not respond well to these vaccines. In this report, we describe the generation of a novel HBsAg molecule containing a Th epitope derived from tetanus toxoid (TT). Using recombinant DNA technology. the TT Th epitope (TTe) was inserted into the HBsAg coding sequence. Using a recombinant adenovirus expression system, HBsAg TTe chimeric protein was produced in A549 cells and found to be secreted into culture medium as 22 nm particles. The chimeric HBsAg particles were readily purified by immunoaffinity chromatography and their immunogenicity was evaluated relative to native HBsAg produced in an adenovirus expression system. When evaluated in inbred and outbred strains of mice, HBsAg TTe was shown to enhance several-fold the anti-HBs response relative to native HBsAg. Further enhanced responses were observed in mice primed with TT. This highly immunogenic form of HBsAg has promise as an improved HBsAg subunit vaccine.


Subject(s)
Epitopes, T-Lymphocyte/immunology , Hepatitis B Surface Antigens/immunology , T-Lymphocytes, Helper-Inducer/immunology , Tetanus Toxoid/immunology , Animals , Female , Hepatitis B Surface Antigens/genetics , Humans , Mice , Mice, Inbred BALB C , Microscopy, Electron , Recombinant Fusion Proteins/immunology , Tetanus Toxoid/genetics , Tumor Cells, Cultured
9.
Biochem Biophys Res Commun ; 254(3): 572-7, 1999 Jan 27.
Article in English | MEDLINE | ID: mdl-9920780

ABSTRACT

Hepatitis C virus (HCV) is dependent on NS2-3 autocleavage and NS5A phosphorylation for its life cycle. We demonstrate that NS5A, when released from the NS2-5 polyprotein of the BK virus strain, is phosphorylated as two distinct forms, pp56 and pp58. Deletion analysis indicates that the appearance of pp58 requires NS2 in cis, while pp56 is NS2 independent. Disruption of NS2-3 autoproteolysis by directed mutagenesis results in loss of pp58. Expression of a construct producing NS2-3 is sufficient to restore pp58 in trans. These data indicate that generation of functional NS2 via autocleavage of the NS2-3 precursor and NS5A phosphorylation are consecutive processes, suggesting coordinate regulation during virus propagation in vivo.


Subject(s)
Viral Nonstructural Proteins/metabolism , Animals , Base Sequence , COS Cells , DNA Primers , Hydrolysis , Phosphorylation , Protein Processing, Post-Translational
10.
J Biol Chem ; 273(15): 9270-8, 1998 Apr 10.
Article in English | MEDLINE | ID: mdl-9535920

ABSTRACT

Estrogen replacement therapy increases plasma concentrations of high density lipoprotein and its major protein constituent, apolipoprotein AI (apoAI). Studies with animal model systems, however, suggest opposite effects. In HepG2 cells stably expressing estrogen receptor alpha (ERalpha), 17beta-estradiol (E2) potently inhibited apoAI mRNA steady state levels. ApoAI promoter deletion mapping experiments indicated that ERalpha plus E2 inhibited apoAI activity through the liver-specific enhancer. Although the ERalpha DNA binding domain was essential but not sufficient for apoAI enhancer inhibition, ERalpha binding to the apoAI enhancer could not be detected by electrophoretic mobility shift assays. Western blotting and cotransfection assays showed that ERalpha plus E2 did not influence the abundance or the activity of the hepatocyte-enriched factors HNF-3beta and HNF-4, two transcription factors essential for apoAI enhancer function. Expression of the ERalpha coactivator RIP140 dramatically repressed apoAI enhancer function in cotransfection experiments, suggesting that RIP140 may also function as a coactivator on the apoAI enhancer. Moreover, estrogen regulation of apoAI enhancer activity was dependent upon the balance between ERalpha and RIP140 levels. At low ratios of RIP140 to ERalpha, E2 repressed apoAI enhancer activity, whereas at high ratios this repression was reversed. Regulation of the apoAI gene by estrogen may thus vary in direction and magnitude depending not only on the presence of ERalpha and E2 but also upon the intracellular balance of ERalpha and coactivators utilized by ERalpha and the apoAI enhancer.


Subject(s)
Apolipoprotein A-I/biosynthesis , Apolipoprotein A-I/genetics , DNA-Binding Proteins/metabolism , Estradiol/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Receptors, Estrogen/metabolism , Transcription, Genetic/drug effects , Adaptor Proteins, Signal Transducing , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors , Binding Sites , Carcinoma, Hepatocellular , Enhancer Elements, Genetic , Hepatocyte Nuclear Factor 3-beta , Hepatocyte Nuclear Factor 4 , Humans , Kinetics , Liver Neoplasms , Luciferases/biosynthesis , Nuclear Receptor Interacting Protein 1 , Phosphoproteins/metabolism , Promoter Regions, Genetic/drug effects , RNA, Messenger/biosynthesis , Receptors, Estrogen/biosynthesis , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/metabolism , Transcription Factors/metabolism , Transfection , Tumor Cells, Cultured
11.
J Steroid Biochem Mol Biol ; 67(3): 233-40, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9879982

ABSTRACT

A novel human estrogen receptor beta (hERbeta) was cloned from human testis mRNA, ovary and thymus cDNA utilizing PCR and 5' RACE methods. The 5' end of hERbeta contained an additional open reading frame, in-frame and upstream of the published clones. hERbeta encodes a protein of 530 amino acids with an approximate molecular weight of 63 kDa and is larger than the previously reported rat, mouse and human protein. To determine the functional role of additional N-terminal amino acids, we compared the transcription functions of receptor lacking (hERbetaT) and receptor containing (hERbetaL) this N-terminal extension. hERbetaL is more active than hERbetaT in transactivating ERE-based reporter genes. hERbetaL, but not hERbetaT, attenuated cytokine mediated NFkappaB activation. Taken together, the additional N-terminal amino acids appear to play a role in modulating estrogen responsive gene expression in vitro.


Subject(s)
Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , DNA Primers/genetics , DNA, Complementary/genetics , Estrogen Receptor beta , Female , Humans , Male , Mice , Molecular Sequence Data , Molecular Weight , Ovary/metabolism , Polymerase Chain Reaction , RNA, Messenger/genetics , Rats , Receptors, Estrogen/chemistry , Testis/metabolism , Thymus Gland/metabolism , Transcriptional Activation
12.
J Cell Biochem ; 65(3): 368-87, 1997 Jun 01.
Article in English | MEDLINE | ID: mdl-9138093

ABSTRACT

Osteoblasts are established targets of estrogen action in bone. We screened 66 conditionally immortalized clonal human osteoblast cell lines for estrogen receptors (ERs) using reverse transcriptase-polymerase chain reaction (RT-PCR) analysis for ER alpha mRNA and transactivation of adenovirus-estrogen response element (ERE)-tk-luciferase by 17 beta-estradiol (17 beta-E2) for functional ER protein. One of these cell lines, termed HOB-03-CE6, was chosen for further characterization. The cells, which were conditionally immortalized with a temperature-sensitive SV40 large T antigen, proliferated at the permissive temperature (34 degrees C) but stopped dividing at the nonpermissive temperature (> or = 39 degrees C). Alkaline phosphatase activity and osteocalcin secretion were upregulated by 1 alpha, 25-dihydroxyvitamin D3 in a dose-dependent manner. The cells also expressed type I collagen and other bone matrix proteins, secreted a variety of growth factors and cytokines, formed mineralized nodules based on alizarin red-S and von Kossa histochemical staining, and responded to dexamethasone, all-trans retinoic acid, and transforming growth factor-beta 1. This cell line expressed 42-fold less ER message than MCF-7 human breast cancer cells, as determined by quantitative RT-PCR. However, adenovirus-ERE-tk-luciferase activity was upregulated three- to fivefold in these cells by 17 beta-E2 with an EC50 of 64 pM. Furthermore, this upregulation was suppressed by co-treatment with the anti-estrogen ICI-182, 780. Cytosolic extracts of these cells specifically bound [125I]-17 beta-E2 in a concentration-dependent manner with a Bmax of 2.7 fmoles/mg protein (approximately 1,200 ERs/cell) and a Kd of 0.2 nM. DNA gel-shift analysis using a [32P]-ERE demonstrated the presence of ERs in nuclear extracts of these cells. Moreover, binding of the extracts to this ERE was blocked by a monoclonal antibody to the human ER DNA-binding domain. We evaluated these cells for 14 of 20 reported endogenous responses to 17 beta-E2 in osteoblasts. Although most of these responses appeared to be unaffected by the steroid, 17 beta-E2 suppressed parathyroid hormone-induced cAMP production, as well as basal interleukin-6 mRNA expression; conversely, the steroid upregulated the steady-state expression of alkaline phosphatase message in these cells. In summary, we have identified a clonal, conditionally phenotypic, human osteoblast cell line that expresses functional ERs and exhibits endogenous responses to 17 beta-E2. This cell line will be a valuable in vitro model for exploring some of the molecular mechanisms of estrogen action in bone.


Subject(s)
Estradiol/pharmacology , Osteoblasts/drug effects , Phenotype , Aged , Alkaline Phosphatase/metabolism , Antigens, Polyomavirus Transforming , Calcitriol/pharmacology , Cell Division , Cell Line , Cell Line, Transformed , Female , Gene Expression/drug effects , Humans , Osteoblasts/cytology , Osteoblasts/metabolism , Osteocalcin/metabolism , Polymerase Chain Reaction , Receptors, Estradiol/genetics , Temperature
13.
Vaccine ; 15(3): 335-9, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9139496

ABSTRACT

Human adenovirus vectors containing intact or largely deleted E3 region were used to construct adenovirus-hepatitis B recombinant viruses (Ad-HepB) and shown to produce substantial amount of recombinant protein, hepatitis B surface antigen (HBsAg), in tissue culture. Previously we showed that these viruses were able to elicit good anti-HBs antibodies in a dog model. In the present study, the Ad-HepB viruses were evaluated for replication and immunogenicity in chimpanzees which sustain permissive infection by human adenoviruses. Recombinants containing entire E3 region showed better replication pattern than their E3 deleted counterparts as evidenced by longer duration and high titers of virus shedding. The effect of E3 region was also seen in the antibody titers against HBsAg in that the E3 containing viruses showed better response than the E3 deleted viruses. The importance of E3 region for the development of adenovirus vectored vaccines is further discussed.


Subject(s)
Adenovirus E3 Proteins/immunology , Adenoviruses, Human/immunology , Hepatitis B Surface Antigens/immunology , Hepatitis B virus/immunology , Recombinant Fusion Proteins/immunology , Virus Replication/immunology , Adenovirus E3 Proteins/genetics , Adenoviruses, Human/genetics , Animals , Genetic Vectors/immunology , Hepatitis B Antibodies/biosynthesis , Hepatitis B Surface Antigens/genetics , Hepatitis B virus/genetics , Humans , Pan troglodytes
14.
J Virol ; 71(1): 657-62, 1997 Jan.
Article in English | MEDLINE | ID: mdl-8985397

ABSTRACT

Posttranslational processing and subcellular localization of the HCV core protein are critical steps involved in the assembly of hepatitis C virus (HCV). In this study, both of these events were investigated by in vitro translation and transient COS-1 cell transfection of core protein expression constructs. Mutations at amino acid residues 173 to 174 and 191 to 192 disrupted processing events at the two putative cleavage sites in the C-terminal hydrophobic region of the core protein, indicating that these residues are implicated in the pathway of core protein maturation. As a result, two forms of core protein, C173 and C191, were detected by immunoblotting. Indirect immunofluorescence experiments showed that core proteins C173 and C191, when produced from HCV full-length protein or various polyprotein precursors, displayed a cytoplasmic localization. The C173 species, however, was translocated to the nucleus when expressed in the absence of C191. These findings indicate that preferential cleavage may occur during core protein maturation and that the association of the C191 with the C173 species may contribute to the distinct subcellular distribution of core protein. This may provide a possible mechanism for the control of the diverse biological functions of core protein during HCV replication and assembly.


Subject(s)
Hepacivirus/metabolism , Protein Processing, Post-Translational , Viral Core Proteins/metabolism , Amino Acid Sequence , Animals , Binding Sites , COS Cells , Hepacivirus/genetics , Humans , Molecular Sequence Data , Subcellular Fractions , Viral Core Proteins/genetics
15.
Virology ; 204(1): 163-9, 1994 Oct.
Article in English | MEDLINE | ID: mdl-8091650

ABSTRACT

Hepatitis C virus (HCV) encodes a polyprotein that is processed to produce the structural and nonstructural proteins of the virus. Nonstructural protein 3 (NS3) is a serine proteinase that cleaves the polyprotein to release the NS4A, NS4B, NS5A, and NS5B proteins. To characterize the substrate specificity of NS3, we synthesized by in vitro translation the polyprotein NS2*-NS3-NS4*P that includes 70% of the NS2 protein, the complete NS3 protein, and 25% of the NS4 protein region attached to substance P, an epitope tag. We demonstrated that NS3 cleaves at the NS3/NS4A junction to release the NS4*P protein. Subsequently, we used this reaction to evaluate the importance of conserved amino acids that flank the NS3/NS4A junction. We replaced amino acids in the P6, P1, and P1' positions of the scissile bond of this junction using site-directed mutagenesis. When the P6 aspartic acid was changed to asparagine, lysine, or serine, NS3-mediated cleavage occurred. When threonine in the P1 position was replaced with other polar amino acids or with amino acids having aliphatic side chains, cleavage occurred, although it was not detected when arginine or tyrosine was present. Replacement of serine in the P1' position with other polar amino acids, with amino acids having aliphatic side chains, or with arginine resulted in NS3-mediated cleavage. Thus, since fewer amino acids in the P1 position supported cleavage than in the P6 or P1' positions, the P1 position of the scissile bond may play a more important role in defining the substrate specificity of the HCV NS3 proteinase.


Subject(s)
Hepacivirus/enzymology , Protein Processing, Post-Translational/physiology , Serine Endopeptidases/metabolism , Viral Nonstructural Proteins/metabolism , Amino Acid Sequence , Amino Acids/physiology , Base Sequence , Hepacivirus/genetics , Molecular Sequence Data , Mutagenesis, Site-Directed , Protein Precursors/genetics , Protein Precursors/metabolism , Serine Endopeptidases/genetics , Substrate Specificity , Viral Nonstructural Proteins/genetics
16.
Vaccine ; 12(7): 607-12, 1994 May.
Article in English | MEDLINE | ID: mdl-8085377

ABSTRACT

In the absence of an adequate small animal model for testing the efficacy of adenovirus-vectored respiratory syncytial virus (RSV) vaccines, a ferret model was established for this purpose. Recombinant adenovirus types 4, 5 and 7 expressing the RSV fusion glycoprotein (F), the attachment glycoprotein (G) or both F and G were constructed previously. These recombinants contain a deletion of a large portion of the E3 region of the respective adenovirus vector. In addition, an Ad7(E3+)F recombinant virus which contains an intact E3 region was constructed to assess whether E3 region functions might enhance vaccine immunogenicity. Evaluation of these viruses in the ferret model demonstrated that Ad4 and Ad5 recombinants, administered intranasally to ferrets, induce stronger seroresponses to RSV than do Ad7 recombinant viruses. Ad7(E3+)F did not show enhanced immunogenicity relative to E3-deleted recombinant viruses. However, measurement of RSV infectivity in nasal washes, following intranasal RSV challenge, showed that five different vaccination regimens, Ad7F/Ad4F, Ad7G/Ad4G, Ad7FG/Ad4FG, Ad4F/Ad7(E3+)F and Ad5F/Ad4F, protected ferrets from RSV infection in a dose-dependent manner.


Subject(s)
Genetic Vectors , Mastadenovirus/genetics , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus, Human/immunology , Vaccines, Synthetic/therapeutic use , Viral Vaccines/therapeutic use , Animals , Antibodies, Viral/biosynthesis , Ferrets , Models, Biological , Respiratory Syncytial Virus Infections/immunology , Viral Fusion Proteins/immunology
17.
J Infect Dis ; 166(4): 769-75, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1527411

ABSTRACT

Recombinant adenovirus type 4, 5, and 7 expressing the fusion glycoprotein (F) gene, the attachment glycoprotein (G) gene, or both F and G genes of respiratory syncytial virus (RSV) was constructed. Intratracheal immunization of dogs with Ad7F induced moderate titers of RSV-neutralizing antibodies. After booster immunization with Ad4F, the dogs developed high titers of RSV-specific antibody. Subsequently, three two-dose vaccination regimens, Ad4F/Ad5F, Ad7G/Ad4G, and Ad7FG/Ad4FG, were compared with Ad7F/Ad4F for immunogenicity and protective efficacy. The results indicated that Ad4F/Ad5F was equal or greater in immunogenicity to Ad7F/Ad4F, but Ad7G/Ad4G and Ad7FG/Ad4FG were less effective than Ad7F/Ad4F in inducing RSV-neutralizing antibody. All vaccination regimens completely protected the lungs of dogs from RSV infection. A chimpanzee was sequentially immunized orally with Ad7F, Ad4F, and Ad5F. A low-level antibody response to RSV was induced after the primary immunization, but no significant increases were observed after booster immunizations.


Subject(s)
Adenoviruses, Human/immunology , Antigens, Viral/genetics , HN Protein , Respiratory Syncytial Viruses/immunology , Viral Fusion Proteins/immunology , Viral Proteins , Viral Vaccines/immunology , Adenoviruses, Human/genetics , Animals , Antibodies, Viral/immunology , Antigens, Viral/administration & dosage , Antigens, Viral/immunology , Dogs , Drug Administration Schedule , Neutralization Tests , Pan troglodytes , Respiratory Syncytial Viruses/genetics , Respiratory Tract Infections/prevention & control , Respirovirus Infections/prevention & control , Vaccination , Viral Envelope Proteins , Viral Fusion Proteins/administration & dosage , Viral Fusion Proteins/genetics , Viral Vaccines/administration & dosage
18.
Curr Opin Biotechnol ; 2(5): 718-22, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1367724

ABSTRACT

Adenoviruses possess a combination of features that make them highly suitable as vectors for expression of heterologous genes. Non-conditional and non-defective adeno-vectors have been constructed to obtain high level expression of a number of foreign genes and some of them have been shown in animal models to exhibit excellent promise as vaccine candidates.


Subject(s)
Adenoviridae/genetics , Genetic Vectors , Animals , Cloning, Molecular/methods , Gene Expression , Genetic Therapy , Humans , Vaccines, Synthetic
19.
J Med Virol ; 32(2): 109-18, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2280256

ABSTRACT

The pathogenesis of chronic liver disease (CLD) due to persistent hepatitis B virus (HBV) infection has not been defined, but the disease activity is believed to correlate with the presence of hepatitis B e-antigen (HBeAg) antigenemia and high viremia. The molecular characterization of an HBV mutant isolated from an HBeAg-negative patient with severe CLD required amplification of the circulating HBV DNA (2 pg/ml) by the polymerase chain reaction (PCR). Direct sequencing of the nucleotides from five independent amplifications of the conserved precore region consistently revealed a G to A mutation in each of the two terminal codons of the precore region. Codon 28 was mutated from tryptophan-encoding TGG to a translational stop codon, TAG; codon 29 preceding the core initiation codon was changed from GGC to GAC. For biologic evaluation of these mutations on HBV replication and expression of HBeAg in vitro, HepG2 cells were transfected with cloned, recircularized mutant HBV DNA. The transfected cells contained subviral core particles in the cytoplasm and secreted mature HBV, without HBeAg, into the medium. The findings present the first evidence that complete HBV genomes can be amplified by PCR and are replication-competent in vitro. The data also indicate that HBeAg is not necessary for replication of HBV and furthermore suggest that HBeAg is not required for the progression of HBV-induced CLD.


Subject(s)
Hepatitis B e Antigens/genetics , Hepatitis B virus/genetics , Hepatitis B/etiology , Mutation , Adult , Base Sequence , Chronic Disease , Cloning, Molecular , DNA, Viral/biosynthesis , Hepatitis B/genetics , Hepatitis B/immunology , Hepatitis B virus/growth & development , Hepatitis B virus/immunology , Humans , Male , Molecular Sequence Data , Polymerase Chain Reaction , Protein Biosynthesis , Terminator Regions, Genetic , Virus Replication
20.
Hepatology ; 11(2): 271-6, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2307406

ABSTRACT

Based on the diversity of nucleotide sequences of cloned hepatitis B virus DNA genomes, we have predicted possible replication of genetic variants of human hepatitis B virus. This prediction is exemplified by studies of a chronic carrier of HBsAg/adw2, who lacked anti-HBc but carried exceedingly high levels of hepatitis B virus DNA in serum. Molecular characterization of a number of clones revealed a restriction map that deviated significantly from the typical pattern of the adw2 subtype, especially around the EcoRI site commonly used as a reference point. Mutations appearing consistently in the precore and core regions included (a) mutation in the precore region resulting in a termination codon after the initiation codon, (b) mutation of the core initiation codon and (c) an inframe insert of 36 nucleotides in the precore region with a new initiation site for the core protein. The 36-nucleotide insertion resulted in a new core protein with 12 extra amino acids at its amino-terminal end. A few scattered point mutations were clustered in the amino-terminal half of the core gene. Although the core protein of this hepatitis B virus variant carried immunologically detectable HBcAg, the absence of a humoral immune response to HBcAg could have been caused by previous infection with human immunodeficiency virus. This naturally occurring human hepatitis B virus variant replicated efficiently without expressing the precore region, confirming previous observations made of the artificial mutants of duck hepatitis B virus.


Subject(s)
DNA, Viral/genetics , Hepatitis B virus/genetics , Hepatitis B/microbiology , Adult , Amino Acid Sequence , Base Sequence , Hepatitis B Antibodies/analysis , Hepatitis B Core Antigens/genetics , Hepatitis B Core Antigens/immunology , Homosexuality , Humans , Male , Molecular Sequence Data , Mutation
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