Use of laser microdissection greatly improves the recovery of DNA from sperm on microscope slides

Traditionally, sperms are isolated from vaginal cell mixtures by preferential extraction methods. Although these methods work well when there is a reasonable amount of DNA present, they are problematic when there are limited amounts (ca. 250 pg). In particular, the analysis of sperm from microscope slides has proven difficult. Here, we describe the use of laser capture microdissection (LM) for the isolation of spermatozoa from microscope slides containing sperms and vaginal cells. Such slides are frequently an important source of evidential material during the forensic investigation of rape and other sexual assaults. Low copy number (LCN) PCR was used to compare profiles of sperm DNA prepared using LM and preferential lysis. LM was found to outperform preferential lysis in 15 out of 16 samples. The application of LM to the processing of actual casework slides, and in particular the potential use of LM for the analysis of old cases, is discussed. Finally, 77 post-coital slides were processed in order to accurately assess the robustness of the technique. There was a significant association between the quality of the male profile recovered and time since intercourse that was independent of the number of sperms analysed, suggesting that the DNA was degraded even though the spermhead was intact.

[Screening for uterine cervical cancer in Belgium in 2003]

Squamous cell cancer of the uterine cervix is associated with a high morbidity and mortality worldwide and in Belgium. Its development is related to the infection by oncogenic human papillomavirus (HPV) types. Cervical cancer is preceded by dysplasic stages (squamous intraepithelial lesions) which can be detected by a Pap smear. The goal of this paper is to review the screening of uterine cervical cancer in Belgium.

Flow cytometry versus histamine release analysis of in vitro basophil degranulation in allergy to Hymenoptera venom

BACKGROUND

Flow cytometry (FCM) has been proposed for specific allergy in vitro testing. We investigated its biological significance for allergy to Hymenoptera venoms and compared it with the routinely performed basophil histamine release test (HRT).

METHODS

Blood samples from 26 allergic and 8 nonallergic donors were incubated with venom at serial concentrations. Basophils were analyzed with anti-CD45-PE-Cyanin 5, Anti-IgE-FITC, and Anti-CD63-Phycoerythrine. HRT was measured by radioimmunoassay.

RESULTS

FCM was as convenient as HRT for measuring basophil reactivity in at least 87% of allergic and 75% of nonallergic subjects. CD63 outer expression was specifically induced in 91% of releaser subjects (86% on HRT) and in 1 of 10 tests in nonallergic donors, or one of six tests (16% on HRT) in allergic patients tested with an irrelevant allergen. Both methods were concordant in 85.7% of the tests. The three discordant patients had low-grade reactions and borderline biological responses on FCM (n = 2) or HRT (n = 1).

CONCLUSIONS

The dynamic, physiologic significance of CD63, the dose-response curve, and dependency on ethylene-diaminetetra acetic acid suggested that both tests reflect the same mechanism.

An extension to the known range of the desert mouse Pseudomys desertor south into the Great Victoria Desert, Western Australia

THE desert mouse Pseudomys desertor is a medium sized rodent (15 – 30 g) which has a widespread distribution throughout the arid zone of Australia (Menkhorst and Knight 2001). It is considered locally abundant in habitats containing samphire, sedge, nitrebush or mature spinifex grasslands. A tolerance to disturbed habitat (from mining or grazing) has also been noted (Read et al. 1999). The distribution of the species once extended from the Murray-Darling through the Flinders Ranges to the Gibson and Great Sandy Deserts, to the west coast and onto Bernier Island (Read et al. 1999; Menkhorst and Knight 2001). Since European colonisation there has been a contraction of the species’ range to the central deserts (Kerle 1995; Read et al. 1999). In Western Australia, the most southerly historical or contemporary record, is from the Wanjarri Nature Reserve (near Mount Keith), 370 km north of Kalgoorlie (D. Pearson pers. comm.; Western Australian Museum fauna database: http://203.30.234.168/). Recently, however, a suspected P. desertor was caught north-west of Queen Victoria Springs (QVS) in the Great Victoria Desert (GPS 30o 03’ 56’’S; 122o 55’ 28’’E), approximately 350 km to the south-east of its most southern known locality. The specimen had the distinctive buff-orange eye ring, size and general features of P. desertor described in Kerle (1995) and Menkhorst and Knight (2001). Prior to release of the specimen, an ear biopsy was obtained for DNA investigation and genomic DNA was extracted from the biopsy via a variation on the salting out procedure of Miller et al. (1988).

2-Methoxyestradiol enhances reactive oxygen species formation and increases the efficacy of oxygen radical generating tumor treatment

In an investigation of the antitumor effects of 2-methoxyestradiol (2-ME) in combination with other reactive oxygen generating treatments, 2-ME (0.5 microM) was found to completely inhibit cell proliferation of rat DS-sarcoma cells in vitro, with 71% of cells dying after exposure to 5 microM 2-ME. Concentration-dependent increases in ROS-formation, lipid peroxidation and mitochondrial changes were also observed, and an elevation in caspase-3 activity resulted in DNA fragmentation and apoptosis. Combination of 2-ME with hypoxanthine and xanthine oxidase enhanced in vitro cytotoxicity. In vivo, 2-ME caused a slight inhibition of tumor growth, with no tumors cured. Combination of 2-ME treatment with localized 44 degrees C hyperthermia, respiratory hyperoxia and xanthine oxidase caused a tumor growth delay with 51% of tumors cured. These results suggest that amplifying the levels of reactive oxygen species within tumor tissue with substances such as 2-ME may prove to be a promising strategy for adjuvant treatment of solid tumors.

Brown bear (Ursus arctos arctos) femoral head and neck excision

A 30-yr-old untamed European female brown bear (Ursus arctos arctos) with a craniodorsal luxation of the right femoral head and bilateral degenerative joint disease of the coxofemoral joint had a femoral head and neck excision following unsatisfactory conservative medical therapy. The bear was injected with zolazepam-tiletamine, and anesthesia was induced with i.v. thiopental and maintained with isoflurane in oxygen via endotracheal tube. A lumbosacral epidural injection of medetomidine-bupivacaine provided additional analgesia. Slight initial cardiorespiratory depression was counteracted with fluid and inotropic drug administration and ventilatory assistance. The bear's gluteal muscle anatomy differs from that of the dog. Recovery was uneventful. The bear was confined indoors for 6 wk and was able to ambulate normally within 6 mo.

Genotypic correlates of resistance to HIV-1 protease inhibitors on longitudinal data: the role of secondary mutations

Direct sequencing of the pol gene was assessed retrospectively with protease inhibitor susceptibility in a longitudinal study. A total of 134 samples from 26 patients were analysed at regular intervals up to 2 years. Patients were included in virological failure despite indinavir, ritonavir or saquinavir based triple-drug therapy. Both the type and number of certain secondary protease mutations modulated the effect of primary mutations on phenotypic resistance. This was notably applicable to L101/V, and to lesser extents to A711V/T. However, combinations of primary mutations, including 154V could predict resistance to the drug used and nelfinavir in more than 80%. In contrast, in vitro cross-resistance to amprenavir was rarely encountered. In addition, there was a relationship between a higher number of key mutations and poorer virological and clinical outcomes, respectively, from 6 and 3 months on. The key mutations were the protease mutations independently conferring phenotypic resistance and/or the reverse transcriptase mutations predicting treatment outcome. This relationship was independent from drug history, viral load and CD4 cell count measurements. In summary, even on a small sample size, sequence-based genotyping seems to be a good prognostic marker when performed longitudinally. In the context of primary resistance mutations, including additional secondary mutations, it may be useful in the prediction of phenotypic and clinical resistance. This should be assessed to optimize treatment monitoring before emergence of broadly cross-resistant virus.

Clinical morbidity in pediatric dialysis patients: data from the Network 1 Clinical Indicators Project

The Health Care Financing Administration (HCFA) has gathered clinical data on end stage renal disease (ESRD) patients since 1994, but details are only available on patients >/=18 years. In this report, we present morbidity data collected prospectively over 12 months from all children (1-18 years) maintained on either hemodialysis (HD) or peritoneal dialysis (PD) within the six-state New England area. During this year, 17 observations were recorded on 14 HD patients (age 13.4+/- 11.3 years) and 36 observations were made on 25 PD patients (age 11.5+/-4.8 years; mean +/- SD). These patients were generally highly functional, attending school at least part time in nearly all cases. Dialysis adequacy index (DAI), defined as the delivered KT/V divided by DOQI guideline values, indicated that patients were well dialyzed (HD 1.41+/-0.1 and PD 1.10+/-0.1; mean +/- SE). When all dialysis patients were grouped and analyzed, the DAI did not correlate with number of hospitalizations, degree of anemia, serum albumin, or type of dialysis. The number of hospitalizations were greater the younger the patient (P<0.01). The need for antihypertensive medications was higher in the children maintained on HD (94%) compared to children on PD (58%) (P<0.01). Lastly, while serum ferritin did not correlate with serum iron, hematocrit or Epo dosage, it was inversely related to serum albumin (P<0.03). We conclude that, in children, (1) exceeding suggested dialysis adequacy may not improve patient morbidity, (2) the need for antihypertensive medications appears greater in children maintained on HD, and (3) inflammation may play a role in determining serum albumin independent of nutrition.

Newer methods of labeling diagnostic agents with Tc-99m

The past several years have seen marked advances in technetium/rhenium chemistry applicable to the preparation of new 99mTc-labeled radiopharmaceuticals. This article focuses on recent developments in technetium chemistry, including the preparation of "3 + 1" complexes, the preparation and use of (99mTc[CO]3)+ complexes for labeling biomolecules, the preparation of rhenium steroid inclusion complexes, improvements in both hydrazinonicotinamide labeling chemistry and in the preformed 99mTc complex method of labeling biomolecules, and new solid-phase separation techniques that may allow the isolation of high specific-activity radiopharmaceuticals in a clinical setting.

Cardioprotective effects of ramipril and losartan in right ventricular pressure overload in the rabbit: importance of kinins and influence on angiotensin II type 1 receptor signaling pathway

BACKGROUND

The role of kinins in the cardioprotective effects of ACE inhibitors remains controversial.

METHODS AND RESULTS

Right ventricular pressure overload in rabbits was produced by pulmonary artery banding for 21 days. Rabbits were untreated, or they received the ACE inhibitor ramipril with or without bradykinin B(1) and B(2) receptor blockers or the angiotensin (Ang) II type I (AT(1)) receptor blocker losartan. Pulmonary artery banding caused right ventricular hypertrophy, depressed papillary muscle contractility, and loss of Ang II contractile effects because of a signaling defect downstream of AT(1) receptors. Paradoxically, AT(1) receptor density and G protein alpha subunits alphaq and alphai1/2 increased. Inotropic responsiveness to the alpha-receptor agonist phenylephrine was normal. Ramipril preserved cardiac contractility, but this effect was attenuated by simultaneous use of kinin receptor blockers. Ramipril also maintained responsiveness to Ang II and prevented AT(1) receptor and G protein upregulation. The simultaneous use of a kinin receptor blocker attenuated but did not prevent upregulation in the AT(1) receptor and G protein. Losartan had no effect on baseline contractility, but it maintained cardiac inotropic responsiveness to Ang II, prevented upregulation of AT(1) receptors, but did not modify G protein upregulation.

CONCLUSIONS

Pressure overload of the right ventricle decreases contractility, uncouples AT(1) receptors to downstream signaling pathways, and changes the expression of components of the AT(1) receptor signaling pathway. Ramipril attenuates these effects via kinins. Interventions that prevent local increases in Ang II or block AT(1) receptors also prevent decreased responsiveness of the AT(1) receptor in this model.

Synthesis, mechanism of action, and antiviral activity of a new series of covalent mechanism-based inhibitors of S-adenosyl-L-homocysteine hydrolase

A direct method for the preparation of 5'-S-alkynyl-5'-thioadenosine and 5'-S-allenyl-5'-thioadenosine has been developed. Treatment of a protected 5'-acetylthio-5'-deoxyadenosine with sodium methoxide and propargyl bromide followed by deprotection gave the 5'-S-propargyl-5'-thioadenosine 4. Under controlled base-catalysis with sodium tert-butoxide in tert-butyl alcohol 4 was quantitatively converted into 5'-S-allenyl-5'-thioadenosine 5 or 5'-S-propynyl-5'-thioadenosine 6. Incubation of recombinant human placental AdoHcy hydrolase with 4, 5, or 6 resulted in time- and concentration-dependent inactivation of the enzyme (K(i): 45 +/- 0.5, 16 +/- 1, and 15 +/- 1 microM, respectively). Compound 4 caused complete conversion of the enzyme from its E-NAD(+) to E-NADH form during the inactivation process. This indicates that 4 is a substrate for the 3'-oxidative activity of AdoHcy hydrolase (type I inhibitor). In contrast, the NAD(+)/NADH content of the enzyme was not affected during the inactivation process with 5 and 6, and their mechanism of inactivation was further investigated. Addition of enzyme-sequestered water on the S-allenylthio group of 5 or S-propynylthio group of 6 within the active site should lead to the formation of the corresponding thioester 7. This acylating-intermediate agent could then undergo nucleophilic attack by a protein residue, leading to a type II mechanism-based inactivation. ElectroSpray mass spectra analysis of the inactivated protein by 5 supports this mechanistic proposal. Further studies (MALDI-TOF and ESI/MS(n) experiments) of the trypsin and endo-Lys-C proteolytic cleavage of the fragments of inactivated AdoHcy hydrolase by 5 were carried out for localization of the labeling. The antiviral activity of 4, 5, and 6 against a large variety of viruses was determined. Significant activity (EC(50): 1.9 microM) was noted with 5 against vaccinia virus.

Dual topology of the hepatitis B virus large envelope protein: determinants influencing post-translational pre-S translocation

The large (L) envelope protein of the hepatitis B virus (HBV) has the peculiar capacity to form two transmembrane topologies via an as yet uncharacterized process of partial post-translational translocation of its pre-S domain across membranes. In view of a current model that predicts an HBV-specific channel generated during virion envelope assembly to enable pre-S translocation, we have examined parameters influencing L topogenesis by using protease protection analysis of wild-type and mutant L proteins synthesized in transfected cells. We demonstrate that contrary to expectation, all determinants, thought to be responsible for channel formation, are dispensable for pre-S reorientation. In particular, we observed that this process does not require (i) the helper function of the HBV S (small) and M (middle) envelope proteins, (ii) covalent dimer formation of envelope chains, or (iii) either of the three amphipathic transmembrane segments of L. Rather, the most hydrophobic transmembrane segment 2 of L was identified as a vital topogenic determinant, essential and sufficient for post-translational pre-S translocation. Cell fractionation studies revealed that pre-S refolding and thus the dual topology of L is established at the endoplasmic reticulum (ER) membrane rather than at a post-ER compartment as originally supposed. Together our data provide evidence to suggest that the topological reorientation of L is facilitated by a host cell transmembrane transport machinery such as the ER translocon.

Toxicity to Bivalve Hemocytes of Pathogenic Vibrio Cytoplasmic Extract

Using a chemiluminescence (CL) test, it had been previously demonstrated that Vibrio pectenicida, which is pathogenic to Pecten maximus larvae, was able to inhibit completely the CL activity of P. maximus hemocytes and partially inhibit those of Crassostrea gigas. Conversely, a Vibrio sp. strain, S322, pathogenic to C. gigas larvae was more active in reducing the CL activity of oyster hemocytes than of scallop hemocytes. Using this same CL biotest, V. pectenicida and S322 cytoplasmic extracts were shown to reproduce CL inhibition while the cytoplasmic extract of a nonpathogenic strain (U1, Pseudoalteromonas) was without effect. Moreover, cytoplasmic extract as well as live V. pectenicida cells provoked, within a few hours, death of P. maximus hemocytes adhering to a glass slide. After partial purification, it was shown that toxic activities of V. pectenicida cytoplasmic extract was due to a toxin, named VHKT (for vibrio hemocyte-killer toxin), which is heat stable, acid and protease resistant, and less than 3 kDa in molecular weight. Attempts to purify VHKT by reverse-phase (C18) HPLC separated activity into the fraction eluted by water at a retention time of 4.02 min.

Variant human immunodeficiency virus type 1 proteases and response to combination therapy including a protease inhibitor

The objective of this observational study was to assess the genetic variability in the human immunodeficiency virus (HIV) protease gene from HIV type 1 (HIV-1)-positive (clade B), protease inhibitor-naïve patients and to evaluate its association with the subsequent effectiveness of a protease inhibitor-containing triple-drug regimen. The protease gene was sequenced from plasma-derived virus from 116 protease inhibitor-naïve patients. The virological response to a triple-drug regimen containing indinavir, ritonavir, or saquinavir was evaluated every 3 months for as long as 2 years (n = 40). A total of 36 different amino acid substitutions compared to the reference sequence (HIV-1 HXB2) were detected. No substitutions at the active site similar to the primary resistance mutations were found. The most frequent substitutions (prevalence, >10%) at baseline were located at codons 15, 13, 12, 62, 36, 64, 41, 35, 3, 93, 77, 63, and 37 (in ascending order of frequency). The mean number of polymorphisms was 4.2. A relatively poorer response to therapy was associated with a high number of baseline polymorphisms and, to a lesser extent, with the presence of I93L at baseline in comparison with the wild-type virus. A71V/T was slightly associated with a poorer response to first-line ritonavir-based therapy. In summary, within clade B viruses, protease gene natural polymorphisms are common. There is evidence suggesting that treatment response is associated with this genetic background, but most of the specific contributors could not be firmly identified. I93L, occurring in about 30% of untreated patients, may play a role, as A71V/T possibly does in ritonavir-treated patients.

CD4+ and CD8+ clonal T cell expansions indicate a role of antigens in ankylosing spondylitis; a study in HLA-B27+ monozygotic twins

Ankylosing spondylitis (AS) is a complex genetic disease in which both MHC and non-MHC genes determine disease susceptibility. To determine whether the T cell repertoires of individuals with AS show signs of increased stimulation by exogenous antigens, CD4+ and CD8+ T cell subsets of five monozygotic HLA-B27+ twins (two concordant and three discordant for AS) and CD8+ T cell repertoires of three healthy HLA-B27+ individuals were characterized by TCR beta-chain (TCRB) CDR3 size spectratyping. Selected TCRB-CDR3 spectra were further analysed by BJ-segment analysis and TCRB-CDR3 from expanded T cell clones were sequenced. In an analysis of all data (519/598 possible TCRB-CDR3 spectra), AS was associated with increased T cell oligoclonality in both CD8+ (P = 0.0001) and CD4+ (P = 0.033) T cell subsets. This was also evident when data were compared between individual twins. Nucleotide sequence analysis of expanded CD8+ or CD4+ T cell clones did not show selection for particular TCRB-CDR3 amino acid sequence motifs but displayed sequence homologies with published sequences from intra-epithelial lymphocytes or synovial T cells from rheumatoid arthritis patients. Together, these results provide support for the hypothesis that responses to T cell-stimulating exogenous or endogenous antigens are involved in the induction and/or maintenance of AS.

Comparison of DNA sequencing and a line probe assay for detection of human immunodeficiency virus type 1 drug resistance mutations in patients failing highly active antiretroviral therapy

The resistance of human immunodeficiency virus type 1 (HIV-1) to drugs is a major cause of antiretroviral treatment failure. We have compared direct sequencing to a line probe assay (LiPA) for the detection of drug resistance-related mutations in 197 clinical samples, and we have investigated the sequential appearance of mutations under drug pressure. For 26 patients with virological failure despite the use of two nucleoside analogues and one protease inhibitor (indinavir [n = 6], ritonavir [n = 10], and saquinavir [n = 10]), genotypic resistance assays were carried out retrospectively every 3 months for up to 2 years by using direct sequencing (TruGene; Visible Genetics) and a LiPA for detection of mutations in the reverse transcriptase (INNO-LiPA HIV-1 RT; Innogenetics) and the protease (INNO-LiPA HIV Protease, prototype version; Innogenetics) genes. Comparison of the results from both assays found rare major discrepancies (<1% of codons analyzed). INNO-LiPA detected more wild-type-mutant mixtures than sequencing but suffered from a high rate of codon hybridization failures for the reverse transcriptase. LiPA detected earlier and more frequently than sequencing the transient mixed virus population that contained I84V, which appears before V82A in the protease sequence. Mutations M461, G48V, and L90M were often transient and drug pressure related. In conclusion, direct sequencing and LiPAs give concordant results for most clinical isolates. LiPAs are more sensitive for the detection of mixed virus populations. Mutation I84V appears in minor populations in the early steps of the pathways of resistance to indinavir and ritonavir. The fact that some mutations can be found only transiently and in minor virus populations highlights the importance of a low detection limit for resistance assays.

The expression of G250/mn/CA9 antigen by flow cytometry: its possible implication for detection of micrometastatic renal cancer cells

Monoclonal antibody (mAb) G250 is a well characterized and specific mAb to renal cell carcinoma (RCC). The gene G250 was recently cloned and was proved to be homologous to MN/CA9. The G250/MN/CA9 antigen was recently explored as a potential marker for RCC. Flow cytometry (FCM) allows quantitative analysis of cells. The present study describes a flow cytometric method to detect this antigen in human cell lines and in malignant and normal renal tissues. Twelve human carcinoma cell lines (HeLa, Colo205, HT29, BxPC3, OVCAR3, SKOV3, ACHN, A704, CAKI-2, SKRC-59, SKRC-10, and SKRC-52), 10 specimens of normal peripheral blood mononuclear cells, and 38 malignant and 36 adjacent normal renal tissues were studied. The malignant and normal renal tissues were disaggregated mechanically into a single-cell suspension, stained by mAb G250, and analyzed by FCM. All 22 of the clear cell carcinomas, 6 of 8 mixed cell carcinomas, and 3 of 6 granular cell carcinomas were positive for G250/MN/CA9 antigen. SKRC-52 and SKRC-10 were strongly positive for G250/ MN/CA9. The G250/MN/CA9 antigen could also be detected in HeLa, SKOV3, HT29, and A704 cells. One chromophobic, one chromophilic cell carcinoma, the normal renal tissues, and normal peripheral blood mononuclear cells were considered as negative. Our results further confirmed that the G250/MN/CA9 antigen was an ideal marker for RCC, especially for clear cell carcinomas, and that this antigen was present in several types of malignant cells. FCM may serve as a fast tool of immunocytochemical detection of renal cancer cells. Flow cytometric detection of renal cancer cells by using mAb G250 should be further explored.

First hemodialysis access selection varies with patient acuity

Timely placement of a reliable permanent vascular access is essential for hemodialysis care quality; National Kidney Foundation Dialysis Outcomes Quality Improvement (NKF-DOQI) guidelines emphasize native arterio-venous (AV) fistulae as preferred access for incident patients. As part of Network One's Vascular Access Quality Improvement Project (QIP) we investigated whether patients' course to end-stage renal disease (ESRD) influenced vascular access selection. Baseline information was obtained for incident (1998) dialysis patients from 6 centers participating in the Network QIP. Patients were subdivided into 3 predefined clinical groups: KNOWN (known chronic renal disease, seen by a nephrologist, with predictable progression to ESRD), CRISIS (KNOWN but with unanticipated medical crisis precipitating ESRD), and UNKNOWN (not known to have chronic renal insufficiency or never seen by a nephrologist before developing ESRD). Two hundred forty patients were identified (median age 69.9, 42% diabetic). Only 43% of the entire population experienced an orderly progression to renal insufficiency. The most frequent initial access was a catheter (54%), followed by a fistula (29%) and a graft (16%), but selection of initial access differed significantly by patient group, with 46% of KNOWN patients receiving a fistula (P <.001). After 2 months of dialysis, the initial access supported dialysis in only 53.7% of the KNOWN patients, and in 59.4% and 45.7% of the CRISIS and UNKNOWN patients, respectively. We conclude that unpredicted, new ESRD patients are common and are less likely to receive a fistula as initial hemodialysis access. Studies should define optimum access management when dialysis requirement is unforeseen.

Three-year effectiveness of highly active antiretroviral treatment in the Luxembourg HIV cohort

Clinical trials have shown that highly active antiretroviral treatment (HAART) is able to reduce HIV plasma viral loads to undetectable in 70% to 90% of patients and to increase CD4 cell counts. HAART in community settings (i.e., nonclinical trial situations) is reported to be much less effective.

STUDY DESIGN

Observational study.

PURPOSE

The aim of our study was to evaluate the effectiveness of protease inhibitor (PI)-based HAART in the Luxembourg HIV cohort after 36 months of treatment in previously treated and untreated patients. The secondary aim was to identify surrogate markers associated with long-term virologic and immunologic outcomes.

PATIENTS AND METHOD

Seventy-three PI-naive patients, who started on HAART, combining one PI and two nucleoside reverse transcriptase inhibitors (NRTIs),with a follow-up of 3 years, were evaluated with plasma viral load and CD4 cell counts every 3 months and were analyzed retrospectively. Patients who had been treated previously with NRTI (n = 48) were at a more advanced stage of disease.

RESULTS

Overall, there was a mean decrease in viral load compared to baseline of -1.89 log RNA copies/mL (SD = 1.40) that persisted at month 36. Sixty-two percent (62%) of patients reached an undetectable viral load (i.e., below 500 copies/mL): 82% and 53% of NRTI-naive and NRTI-experienced patients, respectively (p =.013). CD4 cell counts increased progressively in both groups with a sustained effect (mean increase of 146 cells/mL +/- 241) at month 36. NRTI-naive patients had a mean increase of 257 cells/mL (SD = 305), in contrast to experienced patients who had an increase of 108 cells/mL (SD = 206) at 3 years. Proportions of patients with a CD4 count under 200 cells/mL fell after 3 years for NRTI-naive (from 66% to 43%) and for experienced patients (from 32% to 13%). Predictors of short duration of viral load response were in decreasing order of importance: clinical AIDS, the use of saquinavir hard gel formulation as initial PI, and the number of NRTIs previously used. Viral load response was the only significant predictor of CD4 changes.

CONCLUSION

In a community setting, effectiveness of PI-based HAART at 3 years is still achieved for most patients. NRTI-experienced patients have a good long-term response rate even if it is lower than NRTI-naive patients. A poor treatment response is associated with a more advanced stage of disease before HAART is introduced.