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Biomedical subjects

C Pedersen

Publications and source records attributed to C Pedersen.

At least 109 records · Page 6Linked to original sources
PubMed1996

Genome and chromosome identification in cultivated barley and related species of the Triticeae (Poaceae) by in situ hybridization with the GAA-satellite sequence.

The satellite sequence studied was primarily composed of GAA repeats organized in long tracts of heterochromatic DNA. Fluorescent in situ hybridization (FISH) with the GAA satellite (GAA banding) to the chromosomes of barley, wheat, rye, and other Triticeae species produced banding patterns similar to those obtained by N-banding. The GAA-banding patterns of barley are described in detail and those of 12 other Triticeae species are described briefly. In situ hybridization with the GAA-satellite sequence permits identification of all the chromosomes of barley. It is a valuable alternative to other banding techniques, especially in connection with physical gene mapping by FISH. The application of the GAA-satellite sequence for the characterization of genomes in phylogenetic studies of genera containing the sequence is discussed.

Base Sequence↗
PubMed1996

Quantification of HIV-1 RNA during antiretroviral therapy: association with viral phenotype and development of resistance.

The aim of this study was to analyse the interplay between the treatment responses, as assessed by serum HIV-1 RNA levels and CD4 cell counts, virological phenotype and the development of phenotypic and genotypic resistance. A total of 47 late-stage, HIV-1-infected, antiretroviral-naive patients treated with reverse transcriptase inhibitors (zidovudine or didanosine monotherapy or alternating zidovudine and didanosine) as part of a randomized study and remaining on treatment for a minimum of 1 year were included in the study. Baseline serum HIV-1 RNA levels did not differ between the patients harbouring syncytium-inducing (SI) virus and those harbouring non-syncytium-inducing (NSI) virus (P = 0.66), despite the fact that the group of patients with SI virus had a significantly lower median CD4 cell count (P < 0.00005) and a higher proportion of patients diagnosed with AIDS at study entry (11/19 versus 6/25) than did the group with NSI virus. The patients harbouring SI virus had significantly faster clinical progression than that of the patients harbouring NSI virus (P < 0.001). The patients wit

Anti-HIV Agents↗
PubMed1996

Epidemiology of AIDS-related Kaposi's sarcoma in Europe over 10 years. AIDS in Europe Study Group.

OBJECTIVES: To determine the incidence and risk factors associated with Kaposi's sarcoma (KS) occurrence as an AIDS-defining condition or after the diagnosis of AIDS. DESIGN: Multicentre retrospective cohort study of AIDS in Europe database from 52 clinical centres in 17 European countries. METHODS: Patients' charts (n = 6546) were reviewed and collected in the database of the AIDS in Europe Study Group from 1979 to 1989. At the time of AIDS diagnosis 1394 patients had KS, whereas an additional 525 others developed KS after AIDS diagnosis. Univariate analysis and development of multivariate models determined factors associated with KS occurrence. RESULTS: Frequency of KS as an AIDS-defining condition significantly declined over time (P < 0.0001). In our cohort of patients, homo-/bisexual men from central Europe with CD4 cell counts > 150 x 10(6)/l were statistically more likely to develop KS at the time of AIDS diagnosis (P < 0.0001). For patients with an AIDS diagnosis other than KS, the probability of developing KS during the follow-up was 10 and 24% after 12 and 36 months, respectively. Variables significantly associated with a further KS development were transmission group, central European residence, previous herpes simplex infection other than ulcers, and low CD4 cells (< 150 x 10(6)/l). Previous zidovudine therapy had no influence on KS appearance. For patients who developed KS subsequent to AIDS diagnosis, there was no significant decline of the incidence over the 10-year time period. CONCLUSIONS: This large cohort study clearly shows that demographic data such as sex, transmission group and region of Europe have a major influence on KS development. It also suggests that KS as an AIDS-defining disease occurs earlier in the course of the chronic HIV infection than other opportunistic diseases. Reasons for geographical variations and its declining frequency as an initial AIDS diagnosis remain undetermined.

AIDS-Related Opportunistic Infections↗
PubMed1995

Structure of the Hafnia alvei strain PCM 1188 O-specific polysaccharide.

The lipopolysaccharide was extracted from cells of Hafnia alvei PCM 1188 strain and, after mild acid hydrolysis, the O-specific polysaccharide isolated and characterized. On the basis of sugar and methylation analysis, FAB mass spectrometry and NMR spectroscopy of the polysaccharide and oligosaccharides obtained after Smith degradation, or solvolysis with anhydrous hydrogen fluoride, the repeating unit of the O-specific polysaccharide was shown to be the pentasaccharide: [formula: see text]

Carbohydrate Conformation↗
PubMed1995

Increase in percentage of CD45RO+/CD8+ cells is associated with previous severe primary HIV infection.

The purpose of the study was to examine how memory (CD45RO) and naive (CD45RA) phenotypes of CD4+ and CD8+ T-cell subpopulations changed with respect to progression and duration of human immunodeficiency virus (HIV) infection. Forty-three HIV-seropositive (HIV+) subjects with known time for seroconversion were included in this cross-sectional study. They were divided into the following groups for comparison: persons with and without AIDS, persons who had seroconverted > 72 and < 72 months before entering the study, persons with or without previous severe primary infection, persons who had developed AIDS > 72 and <72 months before entering the study. Furthermore, the HIV+ group was compared with an HIV-seronegative (HIV-) age- and sex-matched group. There was no difference in the proportion of total naive relative to total memory cells between HIV+ and HIV- subjects, showing an equal loss of naive and memory CD4+ cells in this study. Moreover, there was no difference in the proportion of total naive relative to memory CD8+ cells, showing an equal increase in both subgroups of CD8+ cells in HIV+ subjects. However, HIV+ subjects who had experienced severe primary symptoms resembled the AIDS group regarding shift in the CD8 phenotype from naive to memory and by down-regulation of amounts of CD45RA protein. Furthermore, the results showed that during infection with HIV the amounts of both CD45RA and CD45RO markers on CD4+ cells and CD45RA on CD8+ cells were down-regulated, although with different kinetics.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1995

Changes in survival over time after a first episode of Pneumocystis carinii pneumonia for European patients with acquired immunodeficiency syndrome. Multicentre Study Group on AIDS in Europe.

BACKGROUND: Factors associated with improved survival over time for patients with the acquired immunodeficiency syndrome (AIDS) who have Pneumocystis carinii pneumonia at diagnosis are not clearly defined. METHODS: An inception cohort of 2533 patients with AIDS, diagnosed from 1979 to 1989, from 52 centers in 17 European countries was studied. Survival 3 months and 3 years after diagnosis was estimated by Kaplan-Meier life tables. Independent predictors of survival were analyzed by construction of Cox proportional hazards models. RESULTS: Patients in whom AIDS and P carinii pneumonia had been diagnosed before 1988 had a poorer 3-month (ie, short-term) survival, whereas the survival 1 and 2 years after P carinii pneumonia was lower only for patients whose disease was diagnosed before 1987 compared with those with more recent diagnoses. Other variables associated with poorer outcome were greater age, infection via blood transfusion, diagnosis made in south Europe, and coexisting illnesses. After controlling for these prognostic markers in multivariate analysis, improvement in survival over time was still evident. For patients who survived the P carinii pneumonia episode, both zidovudine and secondary prophylaxis for P carinii pneumonia initiated around the time of diagnosis were associated with improved survival, and, after controlling for these treatment variables, no statistically significant improvement in survival over time was observed. CONCLUSIONS: Survival after an episode of P carinii pneumonia has improved within recent years. Increased awareness of early symptoms of P carinii pneumonia and better treatment of the pneumonia may have led to improvement in short-term survival over time, whereas the introduction of zidovudine and increased use of secondary P carinii pneumonia prophylaxis may have resulted in the recent increase in survival 1 and 2 years after the diagnosis. However, 3-year survival remained unchanged over time, implying that the underlying human immunodeficiency virus infection and other complications are not effectively controlled.

AIDS-Related Opportunistic Infections↗
PubMed1995

Changing patterns of Kaposi's sarcoma in Danish acquired immunodeficiency syndrome patients with complete follow-up. The Danish Study Group for HIV Infection (DASHI).

The objective was to study changes in the occurrence of human immunodeficiency virus type 1-related Kaposi's sarcoma and the association with degree of immunodeficiency over time. Danish patients with acquired immunodeficiency syndrome (AIDS) diagnosed between 1979 and 1990 (n = 687) were followed clinically and with consecutive CD4 cell count measurement from time of AIDS-defining illness to date of death or censoring date, whichever came first. The proportion of homo-/bisexual men (n = 520) with Kaposi's sarcoma (n = 100) at AIDS diagnosis declined from 31% before 1985 to 13% in 1990, whereas the proportion of patients who died with Kaposi's sarcoma remained constant over time. Furthermore, the CD4 cell count at time of AIDS for patients diagnosed with Kaposi's sarcoma has declined in recent years. A CD4 cell count < 200 x 106/liter at the time of AIDS diagnosis predicted an increased risk of developing Kaposi's sarcoma after the AIDS diagnosis. Age, antiretroviral therapy, and primary Pneumocystis carinii pneumonia prophylaxis failed to influence the development of Kaposi's sarcoma. Thus, the occurrence of Kaposi's sarcoma remained constant over time but developed later in the course of AIDS and was associated with more severe immunosuppression in recent years.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[AIDS in Denmark. 1. Opportunistic infections and malignant diseases. Danish Study Group for HIV infection].

To examine the distribution of AIDS-defining illnesses among Danish AIDS patients, data on 687 AIDS patients diagnosed in the period from 1980 to 1990 (93% of all reported cases in the period) were collected. The most frequent AIDS-defining illness was Pneumocystis carinii pneumonia followed by candida oesophagitis and Kaposis sarcoma. The proportion of homo/bisexual men presenting with Kaposis sarcoma as the initial AIDS-defining illness declined over time. Patients with extrapulmonary tuberculosis had higher CD4 cell counts than patients presenting with other illnesses. Cytomegalovirus chorioretinitis and atypical mycobacteriosis were seen more frequently after the time of the AIDS diagnosis, and a low CD4 cell count at time of the AIDS diagnosis was a significant predictor for the development of these opportunistic infections during follow-up. Danish AIDS patients present with a wide spectrum of HIV-related illnesses, reflecting their exposure to opportunistic microorganisms and the degree of immune deficiency. The pattern of HIV-related illnesses is changing over time, and therefore continuous surveillance is needed to optimize therapeutic and prophylactic regimens.

AIDS-Related Opportunistic Infections↗
PubMed1995

[AIDS in Denmark. 2. Survival after the diagnosis of AIDS. Danish Study Group for HIV infection].

The survival pattern was studied for 687 Danish AIDS patients (93% of notified cases in the study period) who were diagnosed with AIDS during the period from 1980 to 1990. The median survival was 17 months. Factors significantly associated with a shortened survival were transfusion-acquired HIV infection, age > 40 years, year of diagnosis before 1987, and the presence of either disseminated infection with Mycobacterium avium-complex, Cytomegalovirus chorioretinitis or malignant lymphoma at time of the AIDS diagnosis. There was also a significant association between survival and CD4 cell count at time of AIDS diagnosis. Patients who had CD4 cell counts above 200 x 10(6)/l had twice as long a survival as patients who had CD4 cell counts less than 50 x 10(6)/l. The prognosis of Danish AIDS patients remains poor. The most important determinant of survival time appears to be the degree of immune deficiency at time of diagnosis.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Factors associated with the development of Pneumocystis carinii pneumonia in 5,025 European patients with AIDS. AIDS in Europe Study Group.

This study examined the factors associated with the development of a first episode of Pneumocystis carinii pneumonia (PCP) in 5,025 patients with AIDS, including 1,976 patients with primary PCP at the time of AIDS diagnosis and 635 with primary PCP occurring subsequently. Compared with untreated patients, patients treated with zidovudine were at similar risk of developing PCP during the first year of therapy but were at greater risk after longer intervals of treatment. The following factors were associated with an increased risk of PCP (either at the time of AIDS diagnosis or thereafter): lack of primary PCP prophylaxis, male homosexuality/bisexuality, diagnosis of AIDS in northern Europe, and CD4 cell count below 200 x 10(6)/L at the time of AIDS diagnosis. Patients with severe weight loss had a 60% higher risk of developing PCP during follow-up than those without such weight loss. Thus, the occurrence of PCP depended on geographic location, mode of acquisition of human immunodeficiency virus and AIDS, degree of immunodeficiency, and use of various treatment regimens.

AIDS-Related Opportunistic Infections↗
PubMed1995

HIV-related non-Hodgkin's lymphoma among European AIDS patients. AIDS in Europe Study Group. AIDS in Europe Study Group.

The epidemiology of HIV associated non-Hodgkin's lymphoma (NHL) was investigated in 6550 European patients with AIDS. NHL was diagnosed in 3.5% of all patients at the time of the AIDS diagnosis. Although the probability of being diagnosed with NHL at AIDS diagnosis was significantly higher among intravenous drug users than among homosexual men, and was associated with increasing age, the observed incidences of NHL were more strikingly similar than any differences. The rate of developing NHL after a previous AIDS diagnosis was 2.4 per 100 patient years of follow-up, and remained constant during a 5-year follow-up period. While primary brain lymphomas comprised only 9% of NHL diagnosed at the time of AIDS, they comprised 38% of NHL diagnosed after AIDS (p < 0.001). The prognosis for patients with NHL at AIDS diagnosis was poor with a median survival of 5 months. A diagnosis of primary brain lymphoma was uniformly associated with a poor outcome. It is concluded that the probability of developing NHL in late stage HIV infection is lower than previously anticipated from the results of small studies on patients receiving long-term anti-retroviral therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1994

A convenient access to beta-(1-->4)-linked 2-amino-2-deoxy-D-glucopyranosyl fluoride oligosaccharides and beta-(1-->4)-linked 2-amino-2-deoxy-D-glucopyranosyl oligosaccharides by fluorolysis and fluorohydrolysis of chitosan.

beta-(1-->4)-Linked 2-amino-2-deoxy-D-glucopyranosyl oligosaccharides, in the form of their alpha-glucopyranosyl fluorides at the reducing end, were obtained by fluorolysis of chitosan in anhydrous hydrogen fluoride at room temperature. The average dp depended on the reaction time and was conveniently monitored by 13C NMR spectroscopy, using the signal ratios for beta-(1-->4) bonded C-1 at approximately 98.5 ppm and the C-1 doublet for the terminal glycosyl fluoride moiety at approximately 104 ppm. Preparative fractionation of dp 2-11 glycosyl fluoride oligosaccharides, obtained after 18 h of fluorolysis, was achieved by gel-permeation chromatography on Bio-Gel P-4 with aqueous acetic acid-ammonium acetate as eluent. Hydrolysis of the anomeric fluoride, with either aqueous perchloric acid, or by a sequence involving formation of the C-2 N-trifluoroacetate and subsequent simultaneous hydrolysis of the glycosyl fluoride and the amide substituent with aqueous methanol, yielded the free beta-(1-->4)-linked 2-amino-2-deoxy-D-glucopyranosyl oligosaccharides which were separated, for dp 2-11, by the same gel-exclusion technique. Both oligosaccharide series, either free or in the form of their alpha-glycopyranosyl fluorides, were fully characterized.

Carbohydrate Conformation↗
PubMed1994

[Controlled, clinical trial of isoprinosine administration to HIV-infected patients. Results of a Danish/Swedish multicenter study. The Scandinavian Isoprinosine Study Group].

The safety and efficacy of isoprinosine in HIV-infected individuals were assessed in a multicentre, randomized, double-blind, 24-week study phase, followed by an optional 24-week open treatment phase. The results of the double-blind phase have been reported separately. Of 866 HIV-seropositive individuals randomized, 832 were eligible for efficacy analysis. On completion of the double-blind phase, 596 patients started open treatment. All patients were evaluated with regard to progression to AIDS. Within 48 weeks, 10/412 patients (2.4%) assigned isoprinosine and 27/420 (6.4%) assigned placebo progressed to AIDS (p = 0.005; odds ratio: 2.8, 95% CI: 1.3-6.2). Intention-to-treat analysis showed identical results. No severe adverse reactions or toxicities were observed. We conclude that HIV-infected individuals without AIDS may be safely and effectively treated with isoprinosine.

Acquired Immunodeficiency Syndrome↗
PubMed1994

[Antiviral treatment of HIV infection].

During the past six years Zidovudine has been the main antiviral drug directed against HIV. The indications for its use have slowly been extended and a reduced dose has limited the side effects. The therapeutical gain is a survival benefit of three to nine months. Other nucleoside analogues such as didanosin and zalcitabin have shown antiviral efficacy but the side effects are different from those of zidovudine. A number of drugs, including protease inhibitors and non-nucleoside reverse transcriptase inhibitors have shown antiviral effects, and are being tested in clinical trials. As no single drug appears to be able to control HIV for an extended period of time, combination regimens including multiple drugs, often administered early in the course of infection, seem to be a promising approaches, which are being pursued in a number of clinical trials.

Antiviral Agents↗
PubMed1994

Survival differences in European patients with AIDS, 1979-89. The AIDS in Europe Study Group.

OBJECTIVES: To examine the pattern of survival and factors associated with the outcome of disease in patients with AIDS. DESIGN: Inception cohort. Data collected retrospectively from patients' charts. SETTING: 52 clinical centres in 17 European countries. SUBJECTS: 6578 adults diagnosed with AIDS from 1 January 1979 to 31 December 1989. MAIN OUTCOME MEASURES: Survival after the time of diagnosis. RESULTS: The median survival after diagnosis was 17 months, with an estimated survival at three years of 16% (95% confidence interval 15% to 17%). Patients diagnosed in southern Europe had a shorter survival, particularly immediately after the time of diagnosis, compared with patients diagnosed in central and northern Europe (survival at one year (95% confidence interval) 54% (52% to 56%) 66% (64% to 68%), 65% (63% to 66%), respectively. The three year survival, however, was similar for all regions. The regional differences in survival were less pronounced for patients diagnosed in 1989 compared with earlier years. Improved survival in recent years was observed for patients with a variety of manifestations used to define AIDS but was significant only for patients diagnosed with Pneumocystis carinii pneumonia. The three year survival, however, remains unchanged over time. CONCLUSIONS: Survival of AIDS patients seems to vary within Europe, being shorter in southern than central and northern Europe. The magnitude of these differences, however, has declined gradually over time. Short term survival has improved in recent years, but the long term prognosis has remained equally poor, reflecting the fact that the underlying infection with HIV and many of the complicating diseases remains essentially uncontrolled.

Acquired Immunodeficiency Syndrome↗