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Biomedical subjects

J M Prins

Publications and source records attributed to J M Prins.

At least 37 records · Page 2Linked to original sources

[Dutch Institute for Health Care Improvement revised guideline, 'Sexually transmitted diseases and neonatal herpes'].

The Dutch Institute for Health Care Improvement revised guideline, 'Sexually transmitted diseases and neonatal herpes' summarises the current scientific position on the diagnosis and treatment of a great number of sexually transmitted diseases (STD) and neonatal herpes. Symptomatic treatment of suspected Chlamydia trachomatis infection and gonorrhoea without previous diagnosis is not recommended. Treatment can be started immediately, once samples have been taken. Risk groups eligible for screening or proactive testing on C. trachomatis infection include: partners of C. trachomatis-positive persons, visitors of STD clinics, women who will undergo an abortion, mothers of newborns with conjunctivitis or pneumonitis, young persons of Surinam or Antillean descent, young women with new relationships and individuals whose history indicates risky sexual behaviour. A period of 3 months can be adopted between a risky contact and the HIV test (this used to be 6 months), unless post-exposure prophylaxis was used. For the treatment of early syphilis no distinction is drawn between HIV-infected and non-HIV-infected persons. It is no longer recommended that women in labour with a history of genital herpes are tested for the herpes simplex virus. Virological testing of the neonate is only advised if the mother shows signs of genital herpes during delivery.

Chlamydia Infections↗

Reduced interferon-gamma release in patients recovered from Legionnaires' disease.

BACKGROUND: Legionella pneumophila, a Gram negative intracellular pathogen, causes Legionnaires' disease (LD). Interferon (IFN)-gamma is important for host defence against L pneumophila so reduced IFN-gamma production capacity and/or responsiveness might render humans more susceptible to infection with L pneumophila. METHODS: Seventy seven patients who suffered from LD after a point source outbreak one year earlier participated in the study. Whole blood was incubated with non-specific stimuli (lipopolysaccharide (LPS) or interleukin (IL)-12) or specific stimuli (viable or heat killed L pneumophila) to evaluate IFN-gamma production, and with IFN-gamma to evaluate IFN-gamma responsiveness. Expression of complement receptor 3 on monocytes was determined by flow cytometry. Thirty seven companions who were also exposed but had not developed LD served as controls. RESULTS: Patients released less IFN-gamma than controls in response to stimulation with LPS (mean (SE) 393 (58) pg/ml v 914 (178) pg/ml; p=0.001) and IL-12 (96 (14) pg/ml v 177 (41) pg/ml; p=0.058). IFN-gamma responsiveness, measured by release of IFN-gamma inducible protein (IP)-10, tumour necrosis factor alpha, IL-12 production capacity, and monocyte expression of complement receptor 3, did not differ between patients and controls. IFN-gamma release after stimulation with LPS and IP-10 release after stimulation with IFN-gamma were weakly associated with severity of LD in the former patient group (rho=-0.3, p=0.011 and rho=-0.3, p=0.037, respectively). CONCLUSION: These results suggest that impaired IFN-gamma production may contribute to susceptibility to L pneumophila infection.

Aged↗

[Post-exposure treatment against HIV outside of the hospital in Amsterdam, January-December 2000].

The Infectious Diseases Department of the Amsterdam Public Health Service regularly sees people who have possibly been exposed to human body fluids infected with hepatitis B virus (HBV), hepatitis C virus (HCV) or human immunodeficiency virus (HIV), as a result of incidents in either a non-hospital-related occupation or during their leisure time. Until January 2000, people reporting possible exposure were referred to hospitals for HIV post-exposure prophylaxis (HIV-PEP), whereas for HBV and HCV, the tracing of the infection source and the follow-up took place at the Public Health Service clinic. Since the introduction of a new protocol in January 2000, the Public Health Service as well as a hospital can establish an indication for HIV-PEP and prescribe it. In 2000, 322 persons reported to the Public Health Service. The source was tested in 194 incidents and an HIV test was carried out on 104 occasions. In 19 cases HIV antibodies were found or the source was known to be HIV positive. A total of 50 people were prescribed HIV-PEP; 16 times after a needle-stick accident, 22 times after a sexual accident, 6 times after a bite-wound and 6 times after direct exposure to human blood. The sources of 30 PEP recipients could be tested and after this 16 recipients could stop with the treatment due to a negative HIV test. In 4 cases PEP treatment was stopped following a review of the indication. Therefore, 30 people had an indication to complete the PEP treatment. Of these, more than 80% reported side effects and 3 people had to withdraw from the treatment at an early stage because of this. The implementation of the protocol has resulted in less confusion because the follow-up now takes place at one location. Compared to other studies, the average time between exposure and treatment is shorter and compliance is good. In the period up to 15 May 2001, no seroconversions had been observed.

Accidents↗

Penetration of the nucleoside analogue abacavir into the genital tract of men infected with human immunodeficiency virus type 1.

The male genital tract is considered an anatomical reservoir during therapy for human immunodeficiency virus infection, because the blood-testis barrier may prevent antiretroviral drugs (e.g., the protease inhibitors ritonavir, saquinavir and nelfinavir) from entering the male genital tract. To our knowledge, there are currently no available data on the penetration of the nucleoside analogue abacavir into the male genital tract. Our report shows that abacavir has good penetration into the male genital tract.

Anti-HIV Agents↗

T cell expansions in lymph nodes and peripheral blood in HIV-1-infected individuals: effect of antiretroviral therapy.

OBJECTIVE: To evaluate dynamics in CD8 T cell expansions during highly active antiretroviral therapy (HAART). DESIGN: Various T cell subsets were isolated from blood and lymph nodes and analysed for T cell receptor (TCR) diversity. METHODS: TCR complementarity determining region 3 (CDR3) spectratyping and single-strand conformation polymorphism (SSCP) analyses were performed in combination with sequencing to assess clonality of the subsets. RESULTS: Strongly skewed CDR3 patterns in total CD8 cells and the CD8 subsets CD45RO+CD27+ and CD45RO-CD27+ showed substantial dynamics in dominant CDR3 sizes, resulting in relative improvement of CDR3 size diversity in the first months of therapy. During sustained treatment, TCR diversity changed only moderately. SSCP profiles confirmed oligoclonality of TCR CDR3 perturbations. Various dominant CDR3 sizes for CD4 and CD8 T cells present in lymph nodes, but not in peripheral blood mononuclear cells, before the start of therapy emerged in peripheral blood early during therapy. CONCLUSIONS: HAART induces substantial changes in CD8 TCR diversity, eventually resulting in improvement of the repertoire. Clonal expansions observed in lymph nodes before therapy were observed in peripheral blood after therapy, suggesting that recirculation of CD4 and CD8 T cells from lymph nodes contributes to the early T cell repopulation. Decreased immune activation and possibly naive T cell regeneration subsequently decreased clonal expansions and perturbations in the CD8 TCR repertoire.

Antiretroviral Therapy, Highly Active↗

Concentrations of human immunodeficiency virus type 1 (HIV-1) RNA in cerebrospinal fluid after antiretroviral treatment initiated during primary HIV-1 infection.

In 6 patients with primary human immunodeficiency virus type 1 (HIV-1) infection, concentrations of HIV-1 RNA and beta(2)-microglobulin were monitored in cerebrospinal fluid (CSF) and in plasma during antiretroviral therapy. Four patients had neurological symptoms. At baseline, the CSF of 5 patients had detectable levels of HIV-1 RNA (median, 3.68 log(10) copies/mL; range, <2.60-5.67 log(10) copies/mL), and the CSF of 3 patients had elevated levels of beta(2)-microglobulin. After 8 weeks of treatment, the median concentrations of HIV-1 RNA in CSF had decreased to <2.60 log(10) copies/mL (range, <1.60-3.00 log(10) copies/mL; P=.04) and in plasma to 3.07 log(10) copies/mL (range, 2.57-3.79 log(10) copies/mL; P=.03). Median concentration of beta(2)-microglobulin in CSF had decreased to 1.2 mg/L (range, 0.9-1.7 mg/L; P=.06) and, in plasma, to 1.7 mg/L (range, 1.1-2.2 mg/L; P=.03). After 48 weeks, HIV-1 RNA concentrations in 1 patient were still 1.97 log(10) copies/mL in CSF and 1.51 log(10) copies/mL in plasma, although beta(2)-microglobulin concentrations in CSF and plasma had normalized after 8 weeks.

Antiretroviral Therapy, Highly Active↗

A retrospective, cohort-based survey of patients using twice-daily indinavir + ritonavir combinations: pharmacokinetics, safety, and efficacy.

OBJECTIVE: To describe the pharmacokinetics, safety, and efficacy of twice-daily indinavir + ritonavir regimens DESIGN: A cohort-based survey of HIV-infected patients who either used indinavir 800 mg + ritonavir 100 mg twice daily or indinavir 400 mg + ritonavir 400 mg twice daily. METHODS: Data were extracted from a database of samples sent to our laboratory for measurement of indinavir + ritonavir plasma concentrations. Patient characteristics, safety, and efficacy measurements were collected by retrospective chart review. RESULTS: 100 Patients using 800-mg indinavir + 100-mg ritonavir twice daily and 32 patients using 400-mg indinavir + 400-mg ritonavir twice daily were eligible. Median peak and trough concentrations of indinavir were 6.8 and 0.77 mg/L in the 800/100 group and 2.6 and 0.45 mg/L in the 400/400 group. The most frequently found side effects were nausea and vomiting, which occurred in 22.1% and 34.9% of the patients in the 800/100 and the 400/400 groups, respectively. Viral load data were analyzed for patients who switched from 800-mg indinavir three times daily to one of the indinavir + ritonavir twice daily regimens. At the time of switch 63% (800/100 group) and 60% (400/400 group) had an undetectable viral load and this increased to 77% and 70%, respectively, during follow-up. Patients who switched to the 400/400 group discontinued treatment more frequently than patients who switched to the 800/100 group (70% vs. 26%, p =.008). CONCLUSIONS: Indinavir + ritonavir regimens show improved pharmacokinetic properties, allowing twice-daily dosing with food. Clinical data suggest that safety and efficacy is at least as good as with indinavir three-times-daily regimens without ritonavir. Prospective, comparative trials are needed to properly assess the role in HIV therapy of these twice-daily indinavir + ritonavir regimens.

Cohort Studies↗

OKT3 and IL-2 treatment for purging of the latent HIV-1 reservoir in vivo results in selective long-lasting CD4+ T cell depletion.

Activation of resting T cells has been proposed to purge the reservoir of HIV-1-infected resting CD4+ T cells. We therefore treated three HIV-1-infected patients on antiretroviral therapy with OKT3, a CD3 monoclonal antibody, and recombinant human IL-2. Here we report the profound and partially long-lasting host responses induced by the OKT3 and IL-2 treatment. OKT3/IL-2 induced a strong but transient release of plasma cytokines and chemokines. The percentage CD4+ and CD8+ cells in the blood expressing the activation marker CD38 transiently increased to almost 100%, and in lymph nodes we "observed" a 10-fold increase in the number of dividing Ki67+ cells and increased numbers of apoptotic cells. Following OKT3/IL-2 treatment, a long-lasting depletion of CD4+ cells in the peripheral blood and lymph nodes occurred, suggesting the physical deletion of these cells. Increases in CD4+T cell numbers during the two year followup period were due mainly to increased memory cell numbers. CD8+ cells were also depleted in the blood, but less severely in lymph nodes, and returned to baseline levels within several weeks.

CD4 Lymphocyte Count↗

Pharmacokinetic profiles of nevirapine and indinavir in various fractions of seminal plasma.

Limited data are available on antiretroviral drug concentrations in seminal plasma during a dosing interval. Further, since human ejaculate is composed of fluids originating from the testes, the seminal vesicles, and the prostate, all having different physiological characteristics, drug concentrations in total seminal plasma do not necessarily reflect concentrations in the separate compartments. Five human immunodeficiency virus type 1-infected patients on nevirapine (NVP; 200 mg twice a day [b.i.d.]) and/or indinavir (IDV; 800 mg b.i.d. with ritonavir, 100 mg b.i.d.) regimens used a split ejaculate technique to separate seminal plasma in two fractions, representing fluids from the testes and prostate (first fraction) and fluids from the seminal vesicles (second fraction). Split-ejaculate samples were provided at 0, 2, 5, and 8 h after drug ingestion, on separate days after 3 days of sexual abstinence. NVP and IDV showed time-dependent concentrations in seminal plasma, with peak concentrations in both fractions at 2 and 2 to 5 h, respectively, after drug ingestion. The NVP concentrations were not significantly different between the first and second fractions of the ejaculate at all time points measured and were in the therapeutic range, except for the predose concentration in two patients. The median (range) predose IDV concentrations in the first and second fractions of the ejaculate were 448 (353 to 1,015) ng/ml and 527 (240 to 849) ng/ml, respectively (P = 0.7). In conclusion, NVP and IDV concentrations in seminal plasma are dependent on the time after drug ingestion. Furthermore, our data suggest that NVP and IDV achieve therapeutic concentrations in both the testes and prostate and the seminal vesicles throughout the dosing interval.

Anti-HIV Agents↗

Slower decline of plasma HIV-1 RNA following highly suppressive antiretroviral therapy in primary compared with chronic infection.

OBJECTIVES: To study the effect of highly suppressive antiretroviral therapy on the slopes of HIV-1 RNA decline in primary compared with chronic HIV-1 infection. METHODS: Slopes of HIV-1 RNA decline in plasma were compared before and after the start of highly suppressive antiretroviral therapy from five acutely infected patients who started treatment 2 to 5 weeks following the onset of clinical symptoms. Slopes of decline after the initiation of therapy were also compared with those found in 12 chronically infected individuals on the same therapy. Numbers and percentages of activated CD4 and CD8 T cells at baseline were compared as well. RESULTS: The pre-treatment slopes of HIV-1 RNA decline in the acutely infected individuals increased significantly (P = 0.0001) after the start of anti-retroviral therapy. However, these post-treatment slopes were lower than those found in the chronically infected individuals (P= 0.012). Slopes were inversely correlated (P= 0.012) with baseline HIV-1 RNA. Although the number of CD38+HLA-DR+ CD4 cells was higher in primary infection (P= 0.02), the percentage did not differ between primary and chronic infection. CONCLUSIONS: These findings indicate that antiretroviral therapy contributes significantly to the clearance of HIV-1 during primary infection. Based on the mathematical model the less steep RNA slope following the start of treatment in primary infection can be predicted to be the result of lower clearance of productively infected cells and higher burst size per cell per unit time. This may indicate a growing immune response to HIV-1 in this very early stage of infection.

Acute Disease↗

Increasing cerebrospinal fluid chemokine concentrations despite undetectable cerebrospinal fluid HIV RNA in HIV-1-infected patients receiving antiretroviral therapy.

Only limited data on cerebrospinal fluid (CSF) HIV-1 RNA responses and markers of local inflammation in CSF during antiretroviral therapy are available. HIV-RNA, soluble tumor necrosis factor (TNF)-receptor (sTNFr)-II, monocyte chemoattractant protein (MCP)-1, and interferon-gamma-inducible protein (IP)-10 were measured in the peripheral blood and CSF of 26 antiretroviral-naive HIV-1-positive patients, who were treated with ritonavir (RTV)/saquinavir (SQV) (n = 5), RTV/SQV/stavudine (d4T; n = 8) or zidovudine (AZT)/lamivudine (3TC)/abacavir/nevirapine/indinavir (n = 13). After 8 to 12 weeks of treatment, CSF HIV-RNA dropped to <400 copies/ml in 1 of 5 patients in the RTV/SQV group, 8 of 8 patients in the RTV/SQV/d4T group, and 9 of 10 patients in the five-drug group. CSF sTNFr-II and IP-10 levels increased in patients with detectable CSF HIV-RNA. However, increases in CSF chemokine and sTNFr-II concentrations were also observed in some patients with good CSF HIV-RNA responses. Moreover, CSF MCP-1 concentrations increased in the whole population after 2 months of treatment. Ongoing residual HIV replication in the central nervous system, which cannot be detected with CSF HIV-RNA measurements, may account for this phenomenon.

Anti-HIV Agents↗

Chemotactic activity of CXC chemokines interleukin-8, growth-related oncogene-alpha, and epithelial cell-derived neutrophil-activating protein-78 in urine of patients with urosepsis.

CXC chemokines are chemotactic cytokines that specifically act on neutrophils. To obtain insight into the extent of local production of CXC chemokines during acute pyelonephritis, interleukin (IL)-8, growth-related oncogene (GRO)-alpha, and epithelial cell-derived neutrophil-activating protein (ENA)-78 were measured in urine and plasma samples from patients with culture-proven urosepsis (n=33), healthy human control subjects with sterile urine (n=31), and human volunteers intravenously injected with endotoxin (n=11). Patients had profoundly elevated urine concentrations of chemokines with no (GRO-alpha and ENA-78) or little (IL-8) elevation in plasma. Endotoxin-challenged subjects demonstrated transient increases in plasma chemokine concentrations, with no (GRO-alpha) or little (IL-8 and ENA-78) elevation in urine. Urine from patients exerted chemotactic activity toward neutrophils, which was partially inhibited by neutralizing antibodies against IL-8, GRO-alpha, or ENA-78. During urosepsis, CXC chemokines are predominantly produced within the urinary tract, where they are involved in the recruitment of neutrophils to the urinary compartment.

Acute Disease↗

Evaluation of a second-generation nucleic acid sequence-based amplification assay for quantification of HIV type 1 RNA and the use of ultrasensitive protocol adaptations.

Accurate assessment of plasma HIV RNA levels at low concentrations is clinically important. We evaluated a second-generation quantitative HIV RNA assay (NucliSens HIV-1 QT), and three simple adaptations of the NucliSens standard protocol to lower the lower cutoff level. The assays were evaluated in constructed panels with known HIV RNA concentrations and in clinical samples. Results were compared with those obtained with the first generation (NASBA HIV-1 QT) and with two other commercially available assays: the Amplicor HIV Monitor test and the Quantiplex assay. In a constructed panel, results obtained by NASBA QT were on average 0.13 log(10) copies/ml (SD 0.15) higher than those of NucliSens. The NucliSens assay could quantify HIV RNA in at least 50% of the samples down to 518 (2.71 log(10)) copies/ml and NASBA QT to 5.80 x 10(3) (3.76 log(10)) copies/ml). Both assays correlated well with the known input (R NucliSens = 0.99; R NASBA QT = 0.996), but results were more variable at lower input levels. With the three different ultrasensitive NucliSens adaptations, HIV RNA could be quantified in at least 50% of the samples down to 100 (2.00 log(10)), 46 (1.66 log(10)), and 10 (1.00 log(10)) copies/ml, respectively. In patient samples, Amplicor results were on average 0.11 (SD 0.20) log(10) copies/ml above, NucliSens 0.02 (SD 0.29) copies/ml above, and Quantiplex 0.13 (SD 0.19) copies/ml below the mean of the three assay results per sample. The variation remained the same over the range of RNA levels with all three assays. The NucliSens assay can quantify HIV RNA at lower levels than the NASBA QT and is comparable to other commercially available assays. The lower cutoff of the NucliSens can be lowered down to 10 copies/ml.

Clinical Protocols↗

Soluble granzymes are released during human endotoxemia and in patients with severe infection due to gram-negative bacteria.

Extracellular release of granzymes is considered to reflect the involvement of cytotoxic T lymphocytes and NK cells in various disease states. To obtain insight into granzyme release during bacterial infection, granzyme levels were measured during experimental human endotoxemia and in patients with melioidosis, a severe infection due to gram-negative bacteria. Plasma concentrations of granzyme A (GrA) and GrB increased transiently after endotoxin administration, peaking after 2-6 h. In patients with bacteremic melioidosis, GrA and GrB levels were elevated on admission and remained high during the 72-h study period. In whole blood stimulated with heat-killed Burkholderia pseudomallei, neutralization of tumor necrosis factor, interleukin-12, or interleukin-18 inhibited granzyme secretion, which was independent of interferon-gamma. Stimulation with endotoxin and other gram-negative and gram-positive bacteria also strongly induced the secretion of granzymes, suggesting that granzyme release is a general immune response during bacterial infection. The interaction between the cytokine network and granzymes may play an important immunoregulatory role during bacterial infections.

Adolescent↗

T-cell progenitor function during progressive human immunodeficiency virus-1 infection and after antiretroviral therapy.

Impairment of T-cell renewal has been proposed as contributing to CD4(+) T-cell depletion in persons infected with human immunodeficiency virus-1. We analyzed the T-cell development capacity of progenitors using fetal thymus organ culture. Those who progressed to AIDS had a dramatic loss in T-cell development capacity shortly after seroconversion. In contrast, long-term nonprogressors retained progenitor capacity 8 years after seroconversion. Approximately 70% of patients experienced an improvement in T-cell development capacity after receiving 6 months of potent antiretroviral therapy. Improvement in T-cell development in fetal thymus organ culture correlated with an increase in the number of naive CD4(+) T cells in peripheral blood. Numbers of progenitors in blood and bone marrow after seroconversion or during therapy did not correlate with the change observed in T-cell development capacity. These data provide evidence that HIV-1 infection can interfere with T-cell renewal at the level of the progenitor cell. Interference with T-cell renewal may contribute to CD4(+) T-cell depletion.

Acquired Immunodeficiency Syndrome↗