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M Tersmette

Publications and source records attributed to M Tersmette.

At least 19 recordsLinked to original sources
PubMed2005

[Delayed recognition of falciparum malaria from a non-endemic region in the Dominican Republic].

A 28-year-old patient had suffered from fever, headache, abdominal pains and vomiting for the past three weeks. She had visited a region in the Dominican Republic where the risk of malaria is considered to be low. The complaints were initially regarded as a viral infection. Later, however, she was found to have severe falciparum malaria. She recovered completely following antibiotic therapy. Since November 2004, 17 cases of falciparum malaria have been reported world-wide among travellers to non-endemic regions in the Dominican Republic. Physicians should always consider the possibility of malaria in travellers because a timely diagnosis of falciparum malaria can be of vital importance.

Adult↗
PubMed2002

Catheter replacement in continuous arteriovenous hemodiafiltration: the balance between infectious and mechanical complications.

OBJECTIVE: To assess the optimal moment of central vascular catheter replacement balancing infectious and mechanical complications in continuous renal replacement therapies in critically ill patients with acute renal failure. METHODS: Prospective sequential trial with historical controls to compare liberal catheter replacement when clinically indicated with routine catheter replacement every 5 days in consecutive patients treated by continuous arteriovenous hemodiafiltration in a level I secondary referral intensive care unit of a university-affiliated teaching hospital. Intention-to-treat analysis. MEASUREMENTS AND MAIN RESULTS: Twenty-two patients underwent catheter replacement when clinically indicated (group II), and 21 patients served as historical controls (group I). The groups were comparable for sex, age, Acute Physiology and Chronic Health Evaluation II scores, comorbidity, and creatinin and urea levels at the start of continuous arteriovenous hemodiafiltration. In group I, 71 catheters were used for 346 treatment days, and in group II, 68 catheters were used for 495 treatment days. The mean duration of catheterization was 4.9 +/- 2.0 days vs. 7.3 +/- 4.5 days, respectively (Student's t-test p <.001). There was no significant difference between the incidence of colonization of catheters (46.8% in group I vs. 39.1% in group II; chi-square p =.35) In group I, bacteremia and catheter sepsis occurred in two patients, whereas this did not occur in group II. The occurrence of mechanical complications was comparable in both groups (15.5% in group I vs. 19.1% in group II). There were significantly more mechanical complications with arterial vs. venous catheters (17 vs. 7; chi-square p =.027). CONCLUSION: When catheters were changed as clinically indicated, they remained significantly longer in situ vs. being replaced routinely every 5 days; infectious and mechanical complications were comparable. The incidence of catheter sepsis was low (2.2%), and no prosthesis infection occurred. Catheter replacement when clinically indicated seems to be as safe as routine replacement every 5 days.

APACHE↗
PubMed1999

Strongyloides stercoralis infection: how to diagnose best?

Four patients are described with a Strongyloides stercoralis infection. Several techniques to diagnose this infection are discussed. The so-called Baermann method is emphasised. Especially in chronic infections the combination of serology and the Baermann method seems the best diagnostic approach. Treatment with albendazole or ivermectin are suggested treatments.

Adult↗
PubMed1999

Conversion rate towards a syncytium-inducing (SI) phenotype during different stages of human immunodeficiency virus type 1 infection and prognostic value of SI phenotype for survival after AIDS diagnosis.

The presence of syncytium-inducing (SI) human immunodeficiency virus type 1 (HIV-1) variants is predictive for accelerated progression to AIDS. This study showed that a 4-year survival with AIDS also occurred significantly more often for patients who lacked SI variants. However, multivariate Cox analysis excluded the predictive value of SI viruses for rapid death as being independent from low CD4+ T cell counts. Incidence of appearance of SI variants was increased in persons with CD4+ T cell counts <500/microliter but remained constant in the strata of CD4+ T cell counts <500/microliter, excluding the possibility that loss of immune control is the only prerequisite for the development of SI HIV-1 variants.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Value of laboratory investigations in clinical suspicion of cytomegalovirus-induced upper gastrointestinal tract ulcerations in HIV-infected patients.

To assess the value of laboratory investigations for the diagnosis and treatment of cytomegalovirus-induced upper gastrointestinal tract ulcerations, the medical records and biopsy material from HIV-infected patients were reviewed retrospectively during a 12-month period. Clinical diagnosis of cytomegalovirus (CMV) ulceration, based on characteristic endoscopic appearance of extensive ulceration of the mid- to distal esophageal or gastric mucosa and responsiveness to anti-CMV therapy, was compared with laboratory investigations of biopsies. Laboratory procedures consisted of both histopathological examination of the biopsy specimens and viral culture. Twenty episodes in 12 HIV-infected patients could be evaluated. Clinical diagnosis of CMV ulceration appeared to be justified in 14 of 20 episodes (70%), which were confirmed by laboratory investigations. Of the remaining six episodes, which showed partial or no response to anti-CMV therapy, laboratory investigations were negative in two episodes and discrepant in four episodes (histopathology or viral culture positive). A good response to anti-CMV therapy was more frequent in patients whose biopsies proved positive by histopathological examination and/or viral culture than in patients with negative tests (82% versus 0%), which indicates the importance of both investigations. In conclusion, laboratory diagnosis of CMV-induced upper gastrointestinal tract ulcerations supported the diagnosis and decisions on treatment of CMV-induced upper gastrointestinal tract ulcerations.

Cytomegalovirus↗
PubMed1996

Relation between changes in cellular load, evolution of viral phenotype, and the clonal composition of virus populations in the course of human immunodeficiency virus type 1 infection.

The relationship between the evolution of human immunodeficiency virus type 1 (HIV-1) biologic phenotype, changes in the proportion of infected peripheral blood mononuclear cells, and the relative contribution of non-syncytium-inducing (NSI) and syncytium-inducing (SI) HIV-1 variants to virus load was studied during the course of HIV-1 infection. In 65 HIV-1-infected subjects, the proportion of infected CD4 T cells was higher in persons who carried SI variants. Longitudinal studies revealed that the emergence of SI HIV-1 variants can occur at relatively low numbers of HIV-1-infected cells. Emergence of SI variants frequently coincided with an increase of virus load due to an expansion of both NSI and SI variants, although the contribution of SI viruses to the total virus population significantly increased with time after SI phenotype conversion. These data indicate that NSI to SI phenotype conversion, rather than resulting from high virus load, is part of the sequence of events that leads to increased virus load and CD4 cell depletion.

CD4 Lymphocyte Count↗
PubMed1995

Temporal relationship between elongation of the HIV type 1 glycoprotein 120 V2 domain and the conversion toward a syncytium-inducing phenotype.

The second and third variable domains (V2 and V3) of the human immunodeficiency virus type 1 (HIV-1) gp120 envelope molecule have been shown to be determinants of syncytium-inducing (SI) capacity. Previously we have reported evidence that increased length of the V2 domain and duplication or relocation of potential N-linked glycosylation sites in V2 might be used as prognostic markers for evolution toward an SI phenotype. Here, we used a PCR assay that discriminates a 6-nucleotide difference in the length of the V2 domain, with a sensitivity of 1 elongated V2 domain when present in a background of 125 to 625 short V2 domains. Analysis of DNA isolated directly from PBMCs from 11 HIV-1-infected individuals prior to SI phenotype conversion revealed, however, that the usefulness of this PCR for V2 length polymorphism as predictive marker for SI phenotype evolution is limited. The strong association as observed in our previous study between elongation of the V2 domain and an SI phenotype prompted us to expand our first analysis. An extremely significant correlation was observed between V2 length and virus phenotype for samples obtained at about the moment of SI conversion, but not for samples obtained 3 to 35 months after SI phenotype conversion, suggesting that changes in V2 may be only transiently required to allow SI phenotype evolution. This possibly only transient nature of V2 elongation may explain the discrepancy between results by our group and others.

Amino Acid Sequence↗
PubMed1995

T cell function in vitro is an independent progression marker for AIDS in human immunodeficiency virus-infected asymptomatic subjects.

The predictive value of low T cell reactivity to CD3 monoclonal antibodies for development of AIDS was evaluated and compared with low CD4+ cell numbers and the presence of syncytium-inducing human immunodeficiency virus (HIV) variants in 122 seropositive asymptomatic homosexual men for 4.5 years. Low T cell reactivity was a strong predictor for progression to AIDS in a multivariate proportional hazards analysis using these markers as covariates at entry and as time-dependent covariates. The combination of the three markers was associated with development of AIDS in 6 of 7 men within 15 months. In contrast, the group that lacked any of these markers had a very low risk (11%) for developing AIDS. In groups with one or two of these three markers, progression rates were 33% and 66%, respectively. These data demonstrate that measurement of T cell function in vitro is of value for staging of HIV infection and may be useful for monitoring therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Immunologic and virologic markers determining progression to AIDS.

Infection with the human immunodeficiency virus type 1 (HIV-1) results in a severe immunodeficiency characterized by a depletion of CD4+ T-helper cells. Furthermore, it is well documented that in asymptomatic persons the number of CD4+ cells is also a good predictor of progression to AIDS. However, persons with similar CD4+ cell counts may differ with regard to clinical progression. For this reason the development of additional markers predictive of disease progression is of major clinical importance. In this review three additional progression markers are discussed: rate of decline of CD4+ cells, T-cell reactivity, and HIV biological phenotype. Besides their usefulness as independent progression markers they also provided insight into immunopathologic mechanisms responsible for the eventual development of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1994

An N-glycan within the human immunodeficiency virus type 1 gp120 V3 loop affects virus neutralization.

Carbohydrate side chains of envelope glycoproteins of HIV-1 and other viruses have been postulated to interfere with binding of neutralizing antibodies. So far, however, little evidence for interference of specific N-glycans with virus neutralization has been provided. We used four infectious HIV-1 molecular clones chimeric for their gp 120 V3 domains to study the influence on HIV-1 neutralization of an N-glycan localized within the V3 loop. Two clones lacking the 301N-glycan were at least 8-fold more sensitive to neutralization by two V3-specific monoclonal antibodies (MAbs) and 2- to 10-fold more sensitive to neutralization by a CD4-binding-site-specific human MAb than two HIV-1 clones glycosylated at this site. The affinity of the V3 MAbs for soluble gp120 of the four clones was similar. However, a decreased binding of these MAbs to the gp120 of the two 301N-glycosylated clones was observed when the majority of gp120 was virion-associated during the initial binding step. These findings indicate that the 301N-glycan may interfere with the binding of neutralizing antibodies by limiting the accessibility of neutralization sites or by inducing conformational changes in the HIV-1 gp120 molecule.

Amino Acid Sequence↗
PubMed1994

Development and evaluation of an HIV-1 transfection-neutralization assay.

We developed a transfection-neutralization assay for human immunodeficiency virus type 1 (HIV-1) infectious molecular clones. In this assay CD4 negative adherent cells, transfected in microtiter plates with fixed amounts of proviral DNA of molecular HIV-1 clones, are cocultivated with CD4 positive T cell lines or primary peripheral blood mononuclear cells (PBMC) in the presence of anti-HIV-1 sera or monoclonal antibodies (MAbs). Results obtained with this technique were reproducible and compared favorably with a conventional cell-free infection inhibition assay. The transfection-neutralization assay obviates the need for virus stock preparation and, therefore, is particularly suitable for the evaluation of HIV-1 clones with slow replication kinetics and of recombinant chimeric HIV-1 clones inclined to undergo additional mutations during stock preparation. The potential value of this assay for the analysis of the specificity of neutralizing sera and MAbs was demonstrated in experiments with V3 chimeric molecular clones.

Amino Acid Sequence↗
PubMed1994

Immunological and virological markers determining progression to AIDS.

Infection with the human immunodeficiency virus (HIV-1) results in a severe immunodeficiency characterized by a depletion of CD4+ T-helper cells. Furthermore it is well documented that in asymptomatic persons the number of CD4+ cells is also a good predictor of progression to AIDS. However, persons with similar CD4+ cell counts may differ with regard to clinical progression. For this reason the development of additional markers predictive of disease progression is of major clinical importance. In this review three additional progression markers are discussed: rate of decline of CD4+ cells, T-cell reactivity and HIV biological phenotype. Besides their usefulness as independent progression markers they also provide insight into the immunopathological mechanisms responsible for the final development of AIDS.

Biomarkers↗
PubMed1993

Relation of phenotype evolution of HIV-1 to envelope V2 configuration.

Biological variability of human immunodeficiency virus type-1 (HIV-1) is involved in the pathogenesis of acquired immunodeficiency syndrome (AIDS). Syncytium-inducing (SI) HIV-1 variants emerge in 50 percent of infected individuals during infection, preceding accelerated CD4+ T cell loss and rapid progression to AIDS. The V1 to V2 and V3 region of the viral envelope glycoprotein gp120 contained the major determinants of SI capacity. The configuration of a hypervariable locus in the V2 domain appeared to be predictive for non-SI to SI phenotype conversion. Early prediction of HIV-1 phenotype evolution may be useful for clinical monitoring and treatment of asymptomatic infection.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Prognostic value of HIV-1 syncytium-inducing phenotype for rate of CD4+ cell depletion and progression to AIDS.

OBJECTIVE: To investigate the relation between detection of syncytium-inducing (SI), human immunodeficiency virus type 1 (HIV-1) variants, rate of CD4+ cell decline, and clinical progression. DESIGN: Prospective study during a 2.5-year follow-up period; cohort study with pairwise matched controls. SETTING: The Amsterdam cohort study on the course of HIV-1 infection in homosexual men. PARTICIPANTS: Asymptomatic HIV-1 infected men (n = 225) were tested for the presence of SI variants and were studied prospectively for CD4+ cell decline and clinical progression. In addition, 45 men with a defined moment of appearance of SI variants and 45 matched controls without SI variants were compared for CD4+ cell decline. MEASUREMENTS: Syncytium-inducing variants were detected by cocultivation of peripheral blood mononuclear cells with the MT-2 T-cell line. RESULTS: During a 30-month period, 70.8% of the men with SI variants progressed to AIDS, compared with 15.8% of men without SI variants at entry (P < 0.0001). Multivariable Cox proportional hazard analysis, controlling for CD4+ cell count and HIV-p24 antigenemia, showed a relative hazard for SI variants of 6.7 (95% Cl, 3.5 to 12.7). In the matched control study, before the appearance of SI variants, CD4+ cell counts of 45 men with SI variants and their controls were compared. Syncytium-inducing variants emerged at a mean CD4+ cell count of 0.48 x 10(9)/L(Cl, 0.42 to 0.54), coinciding with the onset of a threefold increased rate of CD4+ cell decline. Men developing AIDS with SI variants had decreased CD4+ cell counts (0.08 x 10(9)/L; 95% Cl, 0.05 to 0.12) at the time of diagnosis compared with persons progressing to AIDS without SI variants (0.25 x 10(9)/L 95% Cl, 0.15 to 0.41) (P = 0.0035]. CONCLUSIONS: The HIV-1 biological phenotype is a practical, binary marker for progression to AIDS, which is independent of decreased CD4+ cell counts and antigenemia. Appearance of SI variants, occurring 2 years before progression to AIDS on the average, is predictive for a significantly increased rate of CD4+ cell decline.

Acquired Immunodeficiency Syndrome↗
PubMed1993

HIV tropism.

Explore the source record for details and available documents.

CD4 Antigens↗
PubMed1993

Early replication steps but not cell type-specific signalling of the viral long terminal repeat determine HIV-1 monocytotropism.

The expression of human immunodeficiency virus type 1 (HIV-1) is enhanced after cell activation because of the interaction of cell-encoded nuclear factors that interact with binding sites in the long terminal repeats (LTRs). Here we studied the contribution of cell type-specific activation signals to differences in cytotropism of HIV-1 variants. Four closely related molecular HIV-1 clones with distinct biological phenotypes and different capacities to replicate in primary monocyte-derived macrophages (MDMs) or T cell lines were used. Sequence analysis of these LTRs revealed variation in functionally important regions. Adaptation of virus variants to particular host cells by differences in LTR responsiveness was analyzed. LTR-CAT constructs were transiently transfected in T cells that were stimulated with T cell-specific activation signals such as combinations of anti-CD3 or anti-CD28 MoAB or in primary monocytes that were stimulated with IL-3, IL-4, or GM-CSF. No differences in responsiveness to cell type-specific signals were demonstrated. To further elucidate the level of restriction in cell tropism, transfection of four full-length infectious molecular HIV-1 clones into 5-day cultured MDMs was performed. From all clones, competent virus could be rescued from MDMs by coculture with PHA-stimulated PBLs. However, following cell-free inoculation, proviral DNA could be detected by PCR analysis only in monocytes exposed to HIV-1 clones that previously were shown to establish productive infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗