Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0349506 (photosensitivity)
 4,145 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Replication-competent molecular clones of feline immunodeficiency virus (FIV) were isolated directly from the DNA of bone marrow cells of a naturally FIV-infected cat. After transfection in a feline kidney cell line (CrFK) and subsequent cocultivation with peripheral blood mononuclear cells (PBMC), the viral progeny of the clones was infectious for PBMC but not for CrFK cells. PBMC infected with these clones showed syncytium formation, a decrease in cell viability, and gradual loss of CD4+ cells. The restriction maps of these clones differed from those obtained for previously described molecular clones of FIV derived from cats in the United States. The predicted amino acid sequence similarity of the envelope genes of the two clones was 99.3%, whereas the similarities of the sequences of the clones to those of two molecular clones from the United States, Petaluma and PPR, were 86 and 88%, respectively. Most of the differences between the amino acid sequences of the two clones and those of the clones from the United States were found in five different hypervariable (HV) regions, HV-1 through HV-5. The viral progeny of one of these clones was inoculated into two specific-pathogen-free cats. The animals seroconverted, and the virus could be reisolated from their PBMC.
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PMID:Isolation and partial characterization of infectious molecular clones of feline immunodeficiency virus obtained directly from bone marrow DNA of a naturally infected cat. 130 91

The long terminal repeat (LTR) of a retrovirus contains sequence elements that constitute a promoter for controlling viral gene expression in infected cells. We have examined regulation of LTR-directed gene expression in feline immunodeficiency virus (FIV), a T-lymphocytopathic lentivirus associated with a fatal AIDS-like disease in domestic cats. Two independent virus isolates, designated FIV-Petaluma and FIV-PPR, have been molecularly cloned and show greater than 85% sequence homology. Both clones (termed pF34 and pPPR) produce infectious virus after transfection of permissive feline cells. Basal promoter activity of the LTRs was measured in various cell lines in transient expression assays using plasmids containing the viral LTR linked to the bacterial chloramphenicol acetyltransferase gene. Both LTRs were strong promoters in several cell lines, although in some cell lines the pF34 LTR had four- to fivefold higher basal activity than the pPPR LTR. FIV LTR mutations affecting the first AP4 site, AP1 site, ATF site, or NF-kappa B site resulted in decreased basal activity of the FIV promoter. Mutational analysis also revealed a negative regulatory element. In cotransfection experiments, both pF34 proviral DNA and pPPR proviral DNA appeared to transactivate either the pF34 LTR or the pPPR LTR; however, levels of transactivation were very low. Cotransfection of both LTRs with FIV subgenomic clones containing various viral open reading frames resulted in low level or no transactivation. The LTRs of both FIV clones responded to cell activation signals in human T-lymphoid cells (Jurkat) treated with phytohemagglutinin and phorbol-12-myristate-13-acetate. Promoter function of both FIV LTRs was also enhanced in cells treated with either forskolin, an inducer of intracellular cyclic-AMP (c-AMP), or dibutyryl c-AMP. Analysis of site-specific mutants showed that a potential AP1 site in the U3 domain of the LTR was required for T-cell activation responses mediated by protein kinase C, whereas a putative ATF site was the target for c-AMP-induced responses mediated by protein kinase A. These studies revealed that cellular transcription factors play a significant role in regulation of FIV gene expression.
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PMID:Regulation of gene expression directed by the long terminal repeat of the feline immunodeficiency virus. 131 May 54

We have molecularly cloned the complete genomic DNA of TM2 strain of feline immunodeficiency virus (FIV) isolated in Japan and compared its nucleotide and the deduced amino acid sequence with those of previously described U.S. isolates, FIV Petaluma and FIV PPR. The infectious molecular clone of FIV TM2 is different from FIV Petaluma in host cell range; the clone can not infect Crandell feline kidney cells which were permissive for FIV Petaluma. The amino acid sequence homologies, in gag, pol, and env genes between FIV TM2 and Petaluma were 90%, 87%, and 81%, respectively. On the other hand, comparative analysis of each gene between FIV Petaluma and PPR showed 96,95, and 85%, respectively. These results suggested that the genomic diversity was present among FIV strains isolated from geographically distant areas. Interestingly, tat- and rev-like short open reading frames contained inframe stop codons in the FIV Petaluma but not in the FIV TM2.
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PMID:Molecular characterization and heterogeneity of feline immunodeficiency virus isolates. 131 25

The nucleotide sequences of the envelope (env) coding regions of two strains of the feline immunodeficiency virus isolated in Zurich, Switzerland (FIVZ1, FIVZ2) have been analysed. In addition, the complete sequence of the FIVZ1 isolate has been determined. Comparisons have been made with the previously published sequences of three North American isolates (PPR and the Petaluma strains FIV34TF10 and FIV14). The isolate FIVZ1 was very similar to the Petaluma strains of FIV and may represent a clonal derivative acquired by 'contamination'. Overall there are between 2.6% and 15.1% amino acid changes in the env gene products of the five isolates. Of the Zurich isolates, FIVZ2 exhibited the greatest divergence to the other viruses and based on its genotype, phenotype and origins probably represents a new isolate of FIV. Possibly the viruses diverged only recently from a common ancestor. Some 31 of the 33 cysteine residues and 17 of the 21 potential N-linked glycosylation sites of the FIV34TF10 env gene product were conserved among all five isolates. The open reading frame 3 (ORF3, or D) which overlaps the env gene (but is encoded in a different frame) has an ATG codon downstream of a potential splice acceptor site in all five isolates, supporting the view that it encodes a viral gene product. In ORF3 of FIVZ1 a stop codon was located 16 amino acids upstream of the stop codon of ORF3 of the other isolates. The ORF4 (or G) of isolate FIVZ2, thought to be the second coding exon of an FIV rev-like gene, contained a nucleotide deletion in amino acid 45 of ORF4, resulting in a--1 frameshift at this position. Comparison of the LTR sequences of the five isolates identified conserved promoter/enhancer elements. A potential stem-loop structure was identified in the R region of the LTRs of all the isolates, despite the heterogeneity of nucleotide sequences in that region. Such structures (TAR) are present in analogous regions of other lentiviruses and are responsible for tat-mediated trans-activation.
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PMID:Identification of conserved and variable regions in the envelope glycoprotein sequences of two feline immunodeficiency viruses isolated in Zurich, Switzerland. 166 Feb 15

The coding sequences of p17 and p24 of the Glasgow-8 strain of feline immunodeficiency virus (FIV) were amplified using the polymerase chain reaction and cloned into plasmid vectors. The predicted amino-acid sequences of FIV/Glasgow-8 p17 and p24 were compared with those of the Petaluma and PPR isolates of FIV. As seen with other retroviruses, these gag gene products are highly conserved, indicating that the protein products would be suitable antigens to detect anti-FIV antibodies in an immunoassay. Both p17 and p24 were stably expressed in Escherichia coli as fusion proteins with glutathione S transferase. A pure preparation of each fusion protein was obtained from induced bacterial lysates by affinity chromatography using glutathione-agarose beads. These recombinant proteins were used in an enzyme-linked immunosorbent assay to detect antibodies directed against FIV p17 and p24 in cat sera. This assay allows the identification of seropositive cats following infection with FIV and has greater sensitivity and specificity than a currently available immunodiagnostic test.
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PMID:Immunodiagnosis of feline immunodeficiency virus infection using recombinant viral p17 and p24. 166 75

Two molecular clones of feline immunodeficiency virus were compared. The first clone, 34TF10, was from a Petaluma, Calif., isolate; the second, PPR, was isolated from a cat in the San Diego, Calif., area. The cats from which the isolates were obtained suffered from chronic debilitating illnesses. The two molecular clones differed in their in vitro host cell range. The 34TF10 clone infected the Crandall feline kidney and G355-5 cell lines, but replicated less efficiently on feline peripheral blood leukocytes. In contrast, the PPR clone productively infected the primary feline peripheral blood leukocytes but not Crandall feline kidney or G355-5 cells. The 34TF10 and PPR clones had an overall sequence identity of 91%. The env gene was the least conserved (85% at the amino acid level). Additionally, the potential open reading frame for a Tat-like protein, ORF 2, contained a stop codon in the 34TF10 isolate which was not found in the PPR clone. This truncation did not prevent in vitro or in vivo replication of 34TF10. Two splice acceptor sites were identified in the 34TF10 clone. One was 5' to the beginning of the putative tat open reading frame, and the other was 5' to the putative vif product. Both of these acceptor sites were conserved in the PPR clone. The long terminal repeats of the viruses were 7% divergent between the two clones, with a lack of conservation in putative NF-kappa B, LBP-1, and CCAAT enhancer-promoter sites.
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PMID:Comparison of two host cell range variants of feline immunodeficiency virus. 169 7

Porphyria cutanea tarda (PCT) is a disorder of heme synthesis characterized by (a) a diminished activity of uroporphyrinogen decarboxylase biochemically and (b) cutaneous lesions secondary to a delayed type of photosensitivity clinically. A human immunodeficiency virus (HIV)-infected patient with PCT is reported and the world literature is reviewed. To date, 17 HIV-seropositive men with PCT have been described. The initial appearance of PCT occurred before or concurrent with the diagnosis of HIV infection in 71% of these individuals (12 men). The median age at onset of PCT was 36 years (range of 20 to 69 years); the median age for the detection of HIV infection was 35 years (range of less than 20 to 71 years). All of these patients had elevated levels of urine porphyrins and blisters on their dorsal hands. Abnormal liver function tests, erosions, hyperpigmentation, hypertrichosis, and skin fragility were also present in some of the men. Polycythemia, serologic evidence of increased iron stores, scarring, milia, and sclerodermoid changes were rarely observed. Successful therapeutic approaches for PCT in men with HIV infection included (a) elimination of PCT-precipitating agents, (b) avoidance of sun exposure, and (c) periodic phlebotomy. Multiple hypotheses for an etiologic role of the HIV and/or an HIV-associated infection, directly or indirectly, in the pathogenesis of PCT in HIV-seropositive men have been suggested.
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PMID:Porphyria cutanea tarda in human immunodeficiency virus-seropositive men: case report and literature review. 175 38

A 56-year-old man was admitted with hemiparesis and shortness of breath. He was positive to human immunodeficiency virus (HIV) antibody and was diagnosed as acquired immunodeficiency syndrome (AIDS) with Kaposi's sarcoma and pneumocystis carinii pneumonia. He developed chronic photosensitivity and vitiligo preceding the onset of the AIDS-related complex (ARC). Association of the two skin lesions with HIV infection is very rare. Although the role of HIV infection in these skin lesions is not significant, the immunological responses in the early course of HIV infection may have contributed to the development of both of these skin lesions.
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PMID:Vitiligo and chronic photosensitivity in human immunodeficiency virus infection. 192 Sep 68

Feline immunodeficiency virus (FIV) encodes the enzyme deoxyuridine-triphosphatase (DU; EC 3.6.1.23) between the coding regions for reverse transcriptase and integrase in the pol gene. Here, we report the in vivo infection of cats with a DU- variant of the PPR strain of FIV and compare its growth properties and tissue distribution with those of wild-type FIV-PPR. The results reveal several important points: (i) DU- FIV is able to infect the cat, with kinetics similar to that observed with wild-type FIV; (ii) both wild-type and DU- FIV-infected specific-pathogen free cats mount a strong humoral antibody response which is able to limit the virus burden in both groups of animals; (iii) the virus burden is reduced in the DU- FIV-infected cats, particularly in tissues such as spleen and salivary gland; and (iv) the mutation frequency in DU- FIVs integrated in the DNA of primary macrophages after 9 months of infection is approximately 5-fold greater than the frequency observed in DU- FIV DNA integrated in T lymphocytes. Mutation rate with wild-type FIV remains the same in both cell types in vivo. The dominant mutations seen in macrophages with DU- FIV are G-->A base changes, consistent with an increased misincorporation of deoxyuridine into viral DNA of DU- FIVs during reverse transcription. Because this enzyme is absent from human immunodeficiency virus type 1 and other primate lentiviruses, virus replication in cell environments with low DU activity may lead to increased mutation and contribute to the rapid expansion of the viral repertoire.
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PMID:Increased mutation frequency of feline immunodeficiency virus lacking functional deoxyuridine-triphosphatase. 763 16

The cutaneous manifestations of human immunodeficiency virus infection include papulosquamous diseases, viral and fungal infections, and neoplastic disorders. Eczematous photosensitivity disorders have been reported in patients infected with the human immunodeficiency virus. We describe a patient with advanced acquired immunodeficiency syndrome who developed photodistributed hypertrophic lichen planus. We believe this is a distinct cutaneous manifestation of human immunodeficiency virus infection.
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PMID:Photodistributed hypertrophic lichen planus in association with acquired immunodeficiency syndrome: a distinct entity. 772 55


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