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H Pfister

Publications and source records attributed to H Pfister.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Presence of genetic rearrangements in E1/E2 regions of episomal HPV 16 isolates from cervical carcinomas 5-8].

OBJECTIVE: Analysis of genetic situations of E1/E2 region of episomal HPV 16 isolates from cervical carcinomas. METHODS: Physical statues of HPV 16 DNAs from cervical carcinomas were analyzed by Southern blot hybridization. E1/E2 regions of episomal RPV 16 isolates were amplified by PCR, and the PCR products were cloned and sequenced. RESULTS: Eight isolates from totally 28 cases showed extrachromosomal HPV 16 DNA. PCR cloned sequence analysis revealed that all the eight isolates contained intact E1/E2 regions, whereas 4 isolates had different ratios of genetic rearrangements, including insertion of E1 repeat sequence and several deletions. Only one case showed the same G deletion at position 1138 as HPV 16 prototype. CONCLUSIONS: DNA rearrangements were present in E1/E2 regions of episomal HPV 16 isolates from cervical cancers and might play a role in tumorigenesis. Different viral genotypes in an identical tumor tissue might indicate that the tumor occurring at the same position of a patient may derive from two or even more cell clones.

DNA, Viral↗
PubMed1999

Enhanced expression and autoimmunity of recombination signal binding protein-jkappa in human dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is a major cause of heart failure in younger individuals. Its prognosis is poor with 40-50% of patients dying within 2 years after diagnosis. Although the etiology of DCM is poorly understood, there is increasing evidence that DCM may represent an autoimmune disease in a significant subset of patients. In order to identify candidate antigens in DCM, we applied a molecular strategy which combines recombinant expression cloning and autoimmunological screening procedures. A left ventricle from a male DCM patient was explanted at heart transplantation and a human DCM left ventricular cDNA-expression library was constructed. 2 x 10(6) clones were immunologically screened with serum collected from the same patient prior transplantation. Subsequent rounds of screening and purification allowed isolation of a positive clone which was sequenced and identified as Recombination Signal Binding Protein-jkappa (RBP-jkappa). RBP-jkappa is an already identified transcription factor, e.g., involved in Epstein-Barr-virus-induced immortalization processes. Radioactively labeled RBP-jkappa protein was synthesized via in vitro translation using the isolated RBP-jkappa cDNA. This RBP-jkappa protein was used for immunoprecipitation reactions to screen sera of healthy controls and patients suffering of DCM for the presence of RBP-jkappa autoantibodies. Analysis revealed that only 31% (n = 16) of healthy but 70.6% of DCM patients (n = 17) carry an autoantibody against RBP-jkappa. Patients suffering from ischemic cardiomyopathy showed a prevalence of 22% of RBP-jkappa autoantibodies. Western analysis with an monoclonal antibody raised against RBP-jkappa showed that RBP-jkappa was overexpressed to 488 +/- 140% in DCM hearts compared to non-failing controls (n = 8). Autologous immunological screening of a cDNA expression library is a powerful and novel technology to gain insights into the etiology of human idiopathic DCM. Human DCM displays an autoimmune response against RBP-jkappa and an overexpression of RBP-jkappa. Since RBP-jkappa is involved in cellular immortalization and exerts antiapoptotic effects, the increased RBP-jkappa autoantibody level during DCM may inhibit this growth-regulating feature of RBP-jkappa. In this setting, enhanced myocardial RBP-jkappa expression could represent a compensatory but ineffective response to counteract the increased rate of apoptosis in DCM. Furthermore, RBP-jkappa may be a useful diagnostic marker for DCM.

Aged↗
PubMed1999

CD40 ligand-CD40 interaction induces chemokines in cervical carcinoma cells in synergism with IFN-gamma.

Cellular immunity plays a major role in controlling human papilloma virus infection and development of cervical carcinoma. Mononuclear cell infiltration possibly due to the action of chemokines becomes prominent in the tumor tissue. In fact, the macrophage chemoattractant protein-1, MCP-1, was detected in cervical squamous cell carcinoma in situ, whereas absent in cultured cells. From this, unknown environmental factors were postulated regulating chemokine expression in vivo. In this study, we show high CD40 expression on cervical carcinoma cells and CD40 ligand (CD40L) staining on attracted T cells in tumor tissue, suggesting a paracrine stimulation mechanism via CD40L-CD40 interactions. We therefore investigated chemokine synthesis in nonmalignant and malignant human papilloma virus-positive cell lines after CD40L exposure. Constitutive expression of MCP-1, MCP-3, RANTES, and IFN-gamma-inducible protein-10 was almost undetectable in all cell lines tested. CD40L was able to induce MCP-1 production; however, despite much higher CD40 expression in malignant cells, MCP-1 induction was significantly lower compared with nontumorigenic cells. After sensitization with IFN-gamma, another T cell-derived cytokine showing minimal effects on CD40 expression levels, CD40 ligation led to a more than 20-fold MCP-1 induction in carcinoma cell lines. An even stronger effect was observed for IFN-gamma-inducible protein-10. Our study highlights the synergism of T cell-derived mediators such as CD40L and IFN-gamma for chemokine responses in cervical carcinoma cells, helping to understand the chemokine expression patterns observed in vivo.

CD40 Antigens↗
PubMed1999

A bioassay for interferon type I based on inhibition of Sendai virus growth.

The expression of type I interferons (IFNs) in eukaryotic cells represents a first line of defense against viral infection. Cells pretreated by IFNs do not support viral replication and are protected from virus-induced cell destruction. A challenge of IFN-pretreated cells with vesicular stomatitis virus (VSV) is frequently used to quantitate this cytokine because, on the one hand, the replication of VSV is highly sensitive to IFNs and, on the other hand, in unprotected cells this virus induces a rapid cytopathic effect that can readily be quantified. However, as VSV may infect humans and is known to cause severe disease in a variety of animal species, this virus must be considered a biohazard. In this paper, we describe a bioassay for bovine IFN using Sendai virus, a paramyxovirus that grows readily in MDBK cells yet is released from these cells in a non-infectious form. The sensitivity and dynamic range of this assay are similar to those of the popular VSV-based IFN assay. We demonstrate that the Sendai-virus-based IFN assay permits rapid quantitation of recombinant bovine type I IFN, and also of native type I IFNs which are present in the supernatants of monocyte-derived macrophages infected with various pathogens. In view of the possible artifacts induced by viruses in samples to be assayed for IFN activity, we evaluated several methods of virus inactivation. Treatment with beta-propiolactone led to virus inactivation without affecting the bioactivity of IFNs as detected in the Sendai-virus-based assay.

Animals↗
PubMed1999

Inducible nitric oxide synthase is expressed in joints of goats in the late stage of infection with caprine arthritis encephalitis virus.

We have studied the expression of the inducible form of nitric oxide synthase (iNOS) in joints of goats infected with the caprine arthritis encephalitis virus (CAEV). Nitric oxide generated by iNOS is thought to play an important role in the pathogenesis of various types of arthritis, especially rheumatoid arthritis (RA) in humans. Surprisingly, iNOS immunoreactivity was found only in joints of long-term infected goats with severe clinical arthritis, whereas-despite the presence of high numbers of inflammatory cells in the synovial tissue-no iNOS immunoreactivity was detected in mildly arthritic and in short-term experimentally infected goats. Most iNOS-positive cells expressed neither MHC class II nor CD68, which suggests that they were fibroblast-like synoviocytes. In situ hybridization studies showed that there was no correlation between iNOS immunoreactivity and detectable virus expression in the joint. In addition, infection of macrophages in vitro-the major host cells of CAEV in vivo-did not lead to increased iNOS mRNA expression. In response to stimulation, similar levels of iNOS expression were observed in infected and in uninfected macrophages. These findings suggest that the expression of iNOS is a feature of late-stage chronic arthritis and is not involved in the development of the inflammatory lesions. Both the lack of co-localization of iNOS protein and viral transcripts in the joint and the finding that CAEV does not stimulate the expression of iNOS in vitro further suggest that iNOS is not directly induced by the virus or the anti-viral immune response in the joint, that it may well, however, be involved in tissue remodelling or scar formation.

Animals↗
PubMed1999

Functional significance of sequence variation in the E2 gene and the long control region of human papillomavirus type 16.

The long control region (LCR) and the E2 protein of human papillomaviruses (HPV) are the most important viral factors regulating transcription of the viral oncogenes E6 and E7. Sequence variation within these genomic regions may have an impact on the oncogenic potential of the virus. Sequence variation in the LCR and in the E2 gene of human papillomavirus type 16 (HPV-16) isolates originating from cervical cancer patients from East Hungary was studied. In 30 samples, sequencing and/or single-strand conformation polymorphism analysis revealed variants belonging to the European variant lineage of HPV-16. These variants differed from the reference European clone only slightly in their E2 and LCR sequences. Three samples represented variants belonging to the Asian-American group. These differed from the published reference sequence at several positions in the LCR and E2 regions. Compared to the reference clone, the LCR clones of the European isolates showed very similar transcriptional activities, while that of an Asian-American isolate had approximately 1.7-fold increased activity. Most of the increased activity of the Asian-American isolate could be ascribed to nucleotide changes found at the 3' end of the LCR (nt 7660-7890). The transcriptional transactivation potentials of the HPV-16 E2 isolates differed only slightly from each other, and the differences seemed to be independent of the taxonomic position of the isolates.

Base Sequence↗
PubMed1999

Reliable high risk HPV DNA testing by polymerase chain reaction: an intermethod and intramethod comparison.

BACKGROUND: The development of a reproducible, sensitive, and standardised human papillomavirus (HPV) polymerase chain reaction (PCR) test is required to implement HPV testing in cervical cancer screening programmes and for triaging women with mild to moderate dysplasia. AIMS: To determine the intermethod agreement between different GP5+/6+ and MY09/11 PCR based protocols for the detection and typing of high risk (HR) HPV DNA in cervical smears and to assess the intramethod reproducibility of the GP5+/6+ PCR enzyme immunoassay (EIA) for HR-HPV detection. METHODS: For the intermethod comparison, crude aliquots of 20 well characterised cervical smears comprising five HPV negative samples, and six and nine samples containing single and multiple HPV infections, respectively, were coded and sent from reference laboratory (A) to three other laboratories. One of these (laboratory B) used the GP5+/6+ PCR-EIA and was provided with standard protocols. Another laboratory (C) used GP5+/6+ PCR combined with sequence analysis and type specific PCR, whereas two laboratories (D and E) used MY09/11 PCR followed by restriction fragment length polymorphism (RFLP) analysis for the detection and typing of HR-HPV. The intramethod agreement of GP5+/6+ PCR-EIA was analysed in a subsequent study with four other laboratories (F to I) on crude aliquots of 50 well characterised cervical smears, consisting of 32 HR-HPV positive and 18 HPV negative samples. Standardised protocols, primers, and probes were also provided by the reference laboratory for HR-HPV detection. RESULTS: In the intermethod comparison, pairwise agreement of the different laboratories with reference laboratory A for the detection of HR-HPV varied between 75% and 100% (kappa values: 0.5 to 1). Typing data revealed a broader range in pairwise agreement rates between 32% and 100%. The highest agreement was found between laboratories A and B using standardised protocols and validated reagents. In the intramethod evaluation, pairwise comparison of the laboratories F to I with reference laboratory A revealed excellent agreement rates from 92% to 100% (kappa values: 0.88 to 1.0) with an overall sensitivity of 97.5% (195/200) and specificity of 99.5% (199/200). CONCLUSIONS: The detection of HR-HPV as a group is highly reproducible with GP5+/6+ PCR-EIA provided that standardised protocols and validated reagents are used.

Cervix Uteri↗
PubMed1999

Expression of inducible nitric oxide synthase in spontaneous bovine bronchopneumonia.

The expression of inducible nitric oxide synthase (iNOS), major histocompatibility class II molecules (MHC-II), CD68, and the calcium-binding proteins S100A8 and S100A9 (also called MRP8 and MRP14, respectively) was assessed in lung tissues from cattle that succumbed to pneumonia. Expression patterns of these markers were related to the types of lung lesion. iNOS expression was only observed in lungs infected with Arcanobacterium pyogenes or Pasteurella haemolytica but not in lungs from cattle with subacute chronic interstitial pneumonia and acute interstitial pneumonia due to Escherichia coli infection. High levels of iNOS were expressed by cells (probably leukocytes) surrounding necrotic foci. Occasionally, iNOS was expressed by intraalveolar macrophages in viable parenchyma, by leukocytes within the airways, and by some chondrocytes in the supporting cartilage of bronchi. Cells expressing MHC-II were distributed relatively evenly throughout areas of inflammation and did not display any clear association with necrotic foci. Cell types expressing MHC-II included type II alveolar epithelial cells, spindle-shaped cells of the interstitium, cells in bronchus-associated lymphoid tissue, and leukocytes in lymph and blood vessels but largely excluded iNOS-positive cells. Likewise, CD68-positive cells were rarely positive for iNOS and were not confined to the areas surrounding necrotic tissue. As with MHC-II and CD68, there was little if any coexpression of iNOS and either of the S100 proteins tested. Thus, in cattle with necrotizing bronchopneumonia, iNOS-expressing cells were largely restricted to the cellular zone surrounding necrotic areas.

Actinomyces↗
PubMed1999

[Affective, somatoform and anxiety disorders in Germany--initial results of an additional federal survey of "psychiatric disorders"].

BACKGROUND AND AIMS: The paper informs about methods and field survey procedures used in the German National Health Interview and Examination Survey--Mental Health Supplement (GHS-MHS)--and provides 12-month prevalence estimates of affective, anxiety and somatoform disorders in the general population. Such data have previously not been available for Germany on a nationwide level. METHODS: Findings are based on a two-stage design: In the first stage all the 7124 participants of the German National Health Interview and Examination Survey (core survey) completed the Composite International Diagnostic-Screener (CIDS) for mental disorders. In the second stage 4181 probands (all screen-positive and a random sample of 50% of the screen-negative subjects) were interviewed with the full Composite International Diagnostic Interview (DIA-X-M-CIDI) by clinical interviewers. The overall response rate was 87.6%. RESULTS: Affective (12-months prevalence estimate: 6.3%), anxiety (9%) and somatoform disorders (7.5%) are widespread in all age groups (18 to 65 years) of the German population; women are significantly more often affected than men. The prevalence rates of somatoform and affective disorders were found to be significantly lower in the former East German Länder as compared to the former West, whereas no such difference was found with regard to anxiety disorders. All disorders resulted in considerable reduction of work productivity during the past month; affective disorders reported on average 1.3 days/month total impairment and 7.2 days/month partial impairment, indicated significantly higher reduction in work productivity than anxiety and somatoform disorders. CONCLUSIONS: Affective, somatoform and anxiety disorders are highly prevalent mental disorders (total: 17.3%) in the German population. The result of a lower morbidity of affective and somatoform disorders in former East Germany was unexpected and requires further clarification. The findings on impairment of work productivity emphasize the economic impact of psychiatric disorders on society.

Adolescent↗
PubMed1999

[Removal of YY1 binding sites in HPV 16 LCR increases viral transforming activities on mouse fibroblasts].

OBJECTIVE: To study the effect of removal of YY1 binding sites within the LCR region of HPV 16 on viral transforming activity. METHODS: Previously we had generated new plasmids carrying HPV 16 whole genome, which contained naturally occurred mutated LCR sequences. The viral transforming abilities on mouse fibroblasts were evaluated in anchorage-independent assays, while the expression and activity of YY1 protein in fibroblasts were tested with EMSA and luciferase assays. RESULTS: YY1 protein was expressed in mouse fibroblasts C127, with ability for DNA binding and repression on P97 activity. Both HPV 16 wild-type DNA and mutated DNAs were transfected into C127 cells and spread to the soft-agarose mediums after selecting with G 418. The growth numbers of the cells transfected with mutated HPV 16 DNAs were 2-10 fold more than that with wild-type HPV 16 DNA. CONCLUSION: Like in epithelial cells or cell lines, transcription regulator YY1 is widely expressed in rodent fibroblasts. Removal of YY1 binding motifs can elevate in the context of the whole genome, the anchorage independent growth ability and the transforming capacity of HPV 16 on the mouse fibroblasts.

Animals↗
PubMed1999

[No switch region is found in the regulatory sequence of HPV 16 for promoter P97].

OBJECTIVE: Cellular transcriptional regulatory factor YY1 represses the activity of the early promoter P97 of HPV 16, but the regulatory activity to early promoter P105 of HPV 18 depends on a switch region which locates at the upstream sequences of YY1 binding sites. This study is to find out whether within the HPV 16 LCR there is such motif. METHODS: DNA sequences of the whole HPV 16 LCR region were analyzed. Two similar switch structures were found. Different CAT reporter plasmids, one containing HPV 16 reference and the other mutated LCRs, both starting at the end of L1 and from the beginning of the enhancer, were generated and transfected in HeLa cells transiently. RESULTS: CAT assays showed there is no change of regulation pattern of YY1 on P97, when the two switch-similar structures were deleted. Sequences analysis also showed that no switch region like motif could be demonstrated in enhancer region, in promoter proximal segment, and even in E6/E7 area. CONCLUSION: It suggests that there is no such switch region within HPV 16 transcriptional regulatory region.

DNA, Viral↗
PubMed1998

A protein related to p21-activated kinase (PAK) that is involved in neurogenesis in the Drosophila adult central nervous system.

Brains are organized by the developmental processes generating them. The embryonic neurogenic phase of Drosophila melanogaster has been studied in detail at the genetic, cellular and molecular level. In contrast, much of what is known of postembryonic brain development has been gathered by neuroanatomical and gene expression studies. The molecular mechanisms underlying cellular diversity and structural organisation in the adult brain, such as the establishment of the correct neuroblast number, the spatial and temporal control of neuroblast proliferation, cell fate determination, and the generation of the precise pattern of neuronal connectivity, are largely unknown. In a screen for viable mutations affecting adult central brain structures, we isolated the mushroom bodies tiny (mbt) gene of Drosophila, which encodes a protein related to p21-activated kinase (PAK). We show that mutations in mbt primarily interfere with the generation or survival of the intrinsic cells (Kenyon cells) of the mushroom body, a paired neuropil structure in the adult brain involved in learning and memory.

Amino Acid Sequence↗
PubMed1998

Test-retest reliability of the computerized DSM-IV version of the Munich-Composite International Diagnostic Interview (M-CIDI).

The structure and content of the Munich-Composite International Diagnostic Interview (M-CIDI) for the assessment of DSM-IV symptoms, syndromes, and diagnoses is described along with findings from a test-retest reliability study. A sample of 60 community respondents were interviewed twice independently by trained interviewers with an average time interval of 38 days between investigations. Test-retest reliability was good for almost all specific DSM-IV core symptom questions and disorders examined, with kappa values ranging from fair for two diagnoses--bulimia (kappa 0.55) and generalized anxiety disorder (kappa 0.45)--to excellent (kappa above 0.72) for all other anxiety disorders and alcohol use disorders. Test-retest reliability for age of onset and time-related questions was fairly consistently high (intra-class correlation values of 0.79 or above), with one notable exception: the assessment of disorders with onset before puberty. We concluded that the M-CIDI is acceptable for respondents, efficient in terms of time needed for and ease of administration, and reliable in terms of consistency of findings over time periods of at least 1 month.

Adolescent↗
PubMed1998

Immunohistology of the early course of lentivirus-induced arthritis.

Caprine arthritis encephalitis (CAE) is a lentiviral infection of goats characterized by mononuclear cell infiltration of various tissues, most prominently the joints, mammary glands and, in young animals, the brain. We have investigated the early stages of arthritis induced by intracarpal and intravenous infection with molecularly cloned CAE virus. Analysis of the synovial membranes by immunohistological methods showed that the proportion of CD8+ T cells peaked around day 12 post-infection. CD4+ T cells increased to a lesser degree. The relative proportion of B cells rose steadily post-infection. At 33 days post-infection, plasma cells accounted for over one third of all inflammatory cells in the inflamed synovium. Histopathologically, the arthritic lesions in the synovial membranes closely resembled those in membranes of animals with a 2-year history of chronic arthritis. Our observations indicate that this type of short-term experimental infection is particularly suitable for studying the pathogenesis of goat lentiviral infection. In addition, our observations support the view that a predominantly humoral (type 2) immune response may contribute to the pathogenesis of CAE.

Animals↗
PubMed1998

Novel human papillomavirus (HPV) DNA sequences from recurrent cutaneous and mucosal lesions of a stoma-carrier.

Recent studies have demonstrated a high prevalence of human papillomavirus (HPV) types originally believed to be restricted to patients with epidermodysplasia verruciformis (EV) in benign and malignant skin tumors of the general population. Other groups detected typical mucosal HPV in skin tumors. We have investigated recurrent leukoplakial cutaneous and mucosal lesions located around the ileostoma of a woman with ulcerative colitis for the presence of HPV. Cutaneous, mucocutaneous, and mucosal ileostoma-biopsies were analyzed by three different polymerase chain reaction protocols for genital, cutaneous, and cutaneous EV-associated HPV types. Polymerase chain reaction products were cloned, sequenced, and submitted to phylogenetic analyses. HPV-DNA sequences of the EV-HPV group could be detected in all biopsies, whereas genital/mucosal or cutaneous HPV types were not found. HPV types detected comprised HPV20, HPV23, HPV38, and four putatively novel HPV types that belong to different clusters of the EV-HPV group B1. Different HPV types prevailed in cutaneous, mucocutaneous, and mucosal lesions and the number of HPV sequences found per lesion varied between one and three. Our data show the association of recurrent lesions around a stoma and at the ileum with known and novel EV-HPV types. These results emphasize the plurality of HPV and yield data for the possible transmission of cutaneous HPV to mucosal areas of the intestine.

Amino Acid Sequence↗
PubMed1998

Prevalence of antibodies against virus-like particles of Epidermodysplasia verruciformis-associated HPV8 in patients at risk of skin cancer.

There is increasing evidence for widespread occurrences of infection with Epidermodysplasia verruciformis-related human papillomaviruses, both in the general population and in immunosuppressed patients. In order to test for the prevalence of antibodies directed against the native L1 epitopes exposed on the surface of the virions, we have established an IgG-specific enzyme-linked immunosorbent assay with L1 virus-like particles of the Epidermodysplasia verruciformis-specific human papillomavirus 8 as antigen to screen 567 representative serum samples from the general population and immunosuppressed/dermatologic patients. Among healthy European donors (n = 210), 7.6% were found to be seropositive. In a group of renal transplant recipients (n = 185) the antibody prevalence was elevated to 21.1%, irrespective of the presence or absence of skin cancer. High positivity rates could be detected among (i) immunocompetent patients with nonmelanoma skin tumors (45.6%, n = 79) and (ii) Psoralene/UVA treated psoriasis patients (42.9%, n = 42). In contrast, anti-human papillomavirus 8-virus-like particle antibodies were found in only 6.8% of Hodgkin lymphoma patients (n = 44).

Antibodies, Viral↗
PubMed1998

Detection of new human papillomavirus sequences in skin lesions of a renal transplant recipient and characterization of one complete genome related to epidermodysplasia verruciformis-associated types.

Human papillomavirus (HPV) DNA, originally isolated from patients suffering from the skin disease epidermodysplasia verruciformis (EV), and a growing number of related sequences have recently been detected in a high percentage of benign and malignant skin lesions of both immunosuppressed and immunocompetent people. HPV L1 DNA fragments (374-389 bp long) from a solar keratosis and a squamous cell carcinoma (SCC) of a renal transplant recipient were amplified, cloned and sequenced. In 54 clones, six different HPV sequences were identified. One of these six corresponded to the known type HPV-8 and two (RTRX3 and RTRX7) have been described previously in cutaneous lesions of immunosuppressed patients. The remaining three sequences were different from all known HPV types: an HPV-9-related sequence (77.4% identity), an RTRX2-related sequence (82.6% identity), and an HPV-22-related sequence (83.7% identity). These three sequences, representing putatively new HPV types, were named RTRX8, RTRX9 and RTRX10, respectively. RTRX7 was found in the majority of clones from both lesions. The complete genome of RTRX7 (7731 bp) was cloned as six overlapping subgenomic fragments, generated by nested PCR with DNA extracts from the SCC. RTRX7 showed a genome organization typical of HPVs associated with EV. The L1 DNA sequence differed by 15% from the corresponding region of its closest known relative, HPV-12; thus, RTRX7 can be regarded as a new HPV type. RTRX7 DNA could not be detected by Southern blot hybridization with the homologous probe, indicating that the DNA concentration was below one copy per 10 cells in the investigated SCC.

Base Sequence↗