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C Apetrei

Publications and source records attributed to C Apetrei.

At least 19 recordsLinked to original sources
PubMed2001

HIV type 1 genetic diversity and genotypic drug susceptibility in the Republic of Moldova.

HIV-1 genetic diversity and, for the first time, genotypic drug susceptibility was investigated for strains circulating in the Republic of Moldova (of the former Soviet Union). Eighty-three samples from adults recently infected by intravenous drug use (IDU) (n = 60), heterosexual contact (n = 8), and from blood donors (n = 15) that tested positive from 1997 to 1998, and originating from different regions of Moldova were serotyped. By group-specific and subtype-specific peptide ELISA, patients were infected by serotype A (n = 65), serotype B (n = 1), or were nontypable (n = 17). Heteroduplex mobility assay (HMA) confirmed 11 subtype A and the one subtype B infection. Analyses of pol and env sequences for six of the IDUs confirmed that they were infected with subtype A strain. These strains clustered tightly with subtype A strains isolated from the former Soviet Union in phylogenetic analysis. No mutations associated with drug resistance were detected. The Republic of Moldova is culturally more closely related to Romania (where subtype F dominates the epidemic), but depends economically on Russia (where subtype A is established among IDUs). Thus, our results suggest that the spread of HIV in this region is driven by drug networks rather than being due to cultural similarities.

Adolescent↗
PubMed2001

Synthetic peptide strategy for the detection of and discrimination among highly divergent primate lentiviruses.

We developed a simple, rapid, inexpensive, and highly sensitive and specific strategy for the detection and lineage differentiation of primate lentiviruses (PIV-ELISA). It is based on the use of two indirect ELISA methods using synthetic peptides mapping the gp41/36 region (detection component) and the V3 region (differentiation component) of four lentivirus lineages, namely SIVcpz/HIV-1 (groups M, O, N, and SIVcpz-gab), SIVmnd, SIVagm, and SIVsm/SIVmac/HIV-2. This strategy was evaluated with panels of sera originating from both humans and nonhuman primates. The human reference panel consisted of 144 HIV Western blot (WB)-positive sera in which the corresponding virus had been genotyped (HIV-1: 72 group M, 28 group O, and 6 group N; HIV-2: 21 subtype A and 10 subtype B; and 7 HIV-1+2) and 105 HIV WB-negative samples. The nonhuman primate reference panel consisted of 24 sera from monkeys infected by viruses belonging to the four lineages included in the PIV-ELISA strategy (5 chimpanzees, 5 macaques, 8 mandrills, and 6 vervets) and 42 samples from seronegative animals. Additional field evaluation panels consisted of 815 human sera from Gabon, Cameroon, and France and 537 samples from 25 nonhuman primate species. All the samples from the two reference panels were correctly detected and discriminated by PIV-ELISA. In the human field evaluation panel, the gp41/36 component correctly identified all the test samples, with 98% specificity. The V3 component discriminated 206 HIV-1 group M, 98 group O, 12 group M+O, and 128 HIV-2 sera. In the primate field evaluation panel, both gp41/36 and V3 detected and discriminated all the WB-positive samples originating from monkeys infected with SIVcpz, SIVagm-ver, SIVmnd-1, SIVmnd-2, SIVdrl, or SIVsun. These results were confirmed by genotyping in every case. Four SIV-infected red-capped mangabeys (confirmed by PCR) were correctly identified by gp41/36, but only two reacted with the V3 peptides in the absence of a specific SIVrcm V3 peptide. Addition of a V3 SIVrcm peptide discriminated all the SIVrcm-positive samples. Fourteen Papio papio samples were positive for SIVsm gp 36 and by WB, but negative by PCR, whereas three Papio cynocephalus samples were positive by gp41/36 but indeterminate by WB and negative by PCR. This combined ELISA system is thus highly sensitive and specific for antibodies directed against HIV and SIV. In addition, the V3-based serotyping results always agreed with genotyping results. This method should prove useful for studies of lentivirus prevalence and diversity in human and nonhuman primates, and may also have the potential to detect previously undescribed SIVs.

Amino Acid Sequence↗
PubMed2001

Variability of human immunodeficiency virus type 2 (hiv-2) infecting patients living in france.

To determine the prevalence of human immunodeficiency virus type 2 (HIV-2) subtypes circulating in France and to identify possible relationships between these subtypes and pathogenesis, we studied 33 HIV-2-infected patients living in France. HIV-2 DNA was directly amplified from peripheral blood mononuclear cells by nested PCR with specific HIV-2 env primers, and the env gene was sequenced. The serological consequences of antigenic variability were studied by using a panel of peptides and by Western blotting. Phylogenetic analysis classified the 33 HIV-2 strains as subtype A (n = 23) or B (n = 10). There were no significant clinical or epidemiological differences between patients infected with either of these two subtypes. There was some evidence for geographical clustering. Subtype A strains from patients originating from the Cape Verde Islands and Guinea Bissau clustered together. The majority of patients infected with subtype B strains originated from the Ivory Coast or Mali. Strains from patients originating in Mali also clustered in subtype A but distinctly from the Cape Verde or Guinea Bissau strains. The subtype B strains showed greater diversity and included some highly divergent strains relative to those previously characterized. The V3 loop of HIV-2 subtypes A and B was found to be quite conserved in comparison with HIV-1. A strong HIV-2 subtype B serological cross-reactivity was found on HIV-1 env antigen by Western blot mostly in the gp41 transmembrane glycoprotein. This could partly explain the double HIV-1 and HIV-2 reactive profiles found in countries where HIV-2 subtype B is prevalent.

Adult↗
PubMed2001

Wild Mandrillus sphinx are carriers of two types of lentivirus.

Mandrillus sphinx, a large primate living in Cameroon and Gabon and belonging to the Papionini tribe, was reported to be infected by a simian immunodeficiency virus (SIV) (SIVmndGB1) as early as 1988. Here, we have identified a second, highly divergent SIVmnd (designated SIVmnd-2). Genomic organization differs between the two viral types; SIVmnd-2 has the additional vpx gene, like other SIVs naturally infecting the Papionini tribe (SIVsm and SIVrcm) and in contrast to the other SIVmnd type (here designated SIVmnd-1), which is more closely related to SIVs infecting l'hoest (Cercopithecus lhoesti lhoesti) and sun-tailed (Cercopithecus lhoesti solatus) monkeys. Importantly, our epidemiological studies indicate a high prevalence of both types of SIVmnd; all 10 sexually mature wild-living monkeys and 3 out of 17 wild-born juveniles tested were infected. The geographic distribution of SIVmnd seems to be distinct for the two types: SIVmnd-1 viruses were exclusively identified in mandrills from central and southern Gabon, whereas SIVmnd-2 viruses were identified in monkeys from northern and western Gabon, as well as in Cameroon. SIVmnd-2 full-length sequence analysis, together with analysis of partial sequences from SIVmnd-1 and SIVmnd-2 from wild-born or wild-living mandrills, shows that the gag and pol regions of SIVmnd-2 are closest to those of SIVrcm, isolated from red-capped mangabeys (Cercocebus torquatus), while the env gene is closest to that of SIVmnd-1. pol and env sequence analyses of SIV from a related Papionini species, the drill (Mandrillus leucophaeus), shows a closer relationship of SIVdrl to SIVmnd-2 than to SIVmnd-1. Epidemiological surveys of human immunodeficiency virus revealed a case in Cameroon of a human infected by a virus serologically related to SIVmnd, raising the possibility that mandrills represent a viral reservoir for humans similar to sooty mangabeys in Western Africa and chimpanzees in Central Africa.

Amino Acid Sequence↗
PubMed1999

High diversity of HIV-1 subtype F strains in Central Africa.

In this paper, we studied the variability of HIV-1 subtype F strains in Africa. For 11 viruses, mainly of Central African origin, different parts of the genome were genetically characterized. For all strains the V3-V5 region of the envelope gene was sequenced, and for 7 strains, the entire envelope gene was studied. For 10 strains, the p24 region of the gag gene was also sequenced. For each region studied, three subgroups in the F subtype were identified, F1, F2, and F3. These three subgroups were supported by high bootstrap values and the intra- and inter-subgroup F distances were comparable to those obtained for the known subtypes A, B, C, D, E, G, and H. In subgroup F1, some African strains clustered with previously described strains from Brazil and Romania, suggesting an African origin of the HIV-1 epidemic in these countries. A more detailed analysis of the gag and the envelope sequences allowed the identification of four recombinant viruses. Our data show a high diversity among subtype F strains, suggesting the presence of new subtypes in the regions studied. If biological differences exist among subtypes, it is important that these subtypes be well defined. The data from our study show that there is a need to clearly identify the different subgroups within the F subtype.

Acquired Immunodeficiency Syndrome↗
PubMed1999

V3 serotyping of HIV-1 infection: correlation with genotyping and limitations.

HIV-1 V3 serotyping is a classification of immunodeficiency viruses based on antibody binding to V3 peptides that allows obtaining information on circulating subtypes that could be important for population-based epidemiologic studies. Recently, several laboratories have developed V3 enzyme-immunoassays (EIAs) using V3 peptides of subtypes A to E. In the present study, the utility of including additional peptides of subtypes F to H to the EIA was evaluated on a panel of 203 well-characterized serum samples from patients with diverse geographic origins (22 countries) and known HIV-1 genotype (79 A, 61 B, 21 C, 7 D, 7 E, 21 F, 6 G, 1 H). The results indicate a high predictive value (ppv) for serotypes B (> or =0.86), D (1) and E (0.88), and confirm the difficulty of predicting genotype A or C based on serotype A or C. Results also indicate that inclusion of the F peptide in the V3 EIAs may be useful (ppv = 0.61), but introduction of peptides G and H failed to demonstrate significant sensitivity or specificity for these subtypes. Correlation between serotyping and amino-acid sequences of the V3 region from 103 samples allowed the identification of key amino-acids that appear essential for subtype-specific seroreactivity.

Amino Acid Sequence↗
PubMed1999

Hepatitis virus infection in haemodialysis patients from Moldavia.

BACKGROUND: Although the epidemiology of hepatitis B (HBV) and C (HCV) now seems well established for Western European countries, in Central and Eastern Europe < 50% of all dialysis centres routinely test for hepatitis C antibodies since testing is not available or is not applied to all patients. This study describes the prevalence, risk factors and clinical significance of HBV and HCV infection for the haemodialysis population of the North Eastern region of Romania, Moldavia. METHODS: The presence of HBV antigens was determined with an ELISA kit (Wellcome, Abbot) and HCV antibodies with the ELISA-3 Ortho-HCV, third generation test. The following individual data were collected: gender, age, duration of dialysis, rural/urban domicile, actual and previous HBV status, actual HCV status, known acute, clinically evident hepatitis episodes in the last 3 years, monthly alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) levels, complete biochemical hepatic assessment at the time of the study, transfusions for the past 3 years and family history. RESULTS: HBV and HCV prevalences were 17% (stable over the last 3 years) and 75%, respectively; co-infection was seen in 10% of the subjects. Hospitalization (nosocomial infection) for HBV, blood transfusions and duration on dialysis for HCV, emerged as the main risk factors for hepatitis infection. Socio-economic conditions appear to be equally important for HCV infection, since the prevalence was significantly higher among patients from rural, underdeveloped areas than urban areas (80.8 vs 60.3%), and infection was already present in a large proportion of patients (47%) before starting dialysis, without being related to previous disease duration or blood transfusions. HBV and/or HCV was not associated with a worse clinical or biochemical profile at the time of the study. However, infected patients had significantly more previous cytolytic episodes, with higher, transient increases in ALAT and ASAT levels. CONCLUSIONS: HCV infection is endemic among dialysis centres in Moldavia. Apart from previously well-known risk factors for hepatitis infection, our study demonstrates the negative impact of socio-economic underdevelopment. Simple measures such as enforced general asepsia rules, careful disinfection and equipment sterilization, routine testing of patients from economically disadvantaged areas and monthly, serial determination of hepatic enzymes should be the common practice in dialysis centres in Romania.

Adult↗
PubMed1998

HIV type 1 diversity and the reliability of the heteroduplex mobility assay.

We investigated HIV-1 diversity by means of heteroduplex mobility assay (HMA) genotyping. We studied 199 samples from patients originating from 26 countries and living in France. The HMA successfully genotyped 182 (91%) of these samples, as follows: 77 (42%) subtype A, 57 (31%) subtype B, 5 (3%) subtype C, 5 (3%) subtype D, 8 (4%) subtype E, 22 (12%) subtype F, 5 (3%) subtype G, and 3 (2%) subtype H. We were not able to genotype 12 samples by means of the HMA. These latter strains were sequenced, and phylogenetic analyses revealed that they were highly divergent subtype A-, D-, or G-related strains. Eight (of 12) subtype D strains were indeterminate by HMA, owing to the broad intrasubtype diversity, suggesting that new reference subtype D plasmids are required, as previously proposed. Thirty-seven strains belonging to the different subtypes were sequenced, and the results showed perfect concordance with the HMA results. Interlaboratory quality controls confirmed the reliability of the HMA for HIV-1 subtyping, despite the extensive viral variability. However, plasmid selection must be continuously revised to cover viral diversification.

Amino Acid Sequence↗
PubMed1998

HIV-1 diversity in Romania.

OBJECTIVES: To evaluate the prevalence and the dynamics of HIV-1 subtypes in Romanian adults and children, and to investigate the origins of the nosocomial epidemic. DESIGN: A total of 1000 serum and plasma samples, from adults (n = 579) and children (n = 421) who were diagnosed as being HIV-1-infected during 1990-1997 in 39 of the 41 Romanian districts, were serotyped. Viral DNA was isolated from blood samples of 84 patients and the viruses were genotyped. METHODS: Serotyping was performed with a peptide subtype-specific enzyme immunoassay (SSEIA), based on in vitro competition for antibody binding between the representative V3 peptides of the different clades (A-F). Proviral HIV-1 DNA was genotyped by heteroduplex mobility assay or by sequence analysis of the C2-V3 env region. RESULTS: SSEIA showed that 93% of the samples from horizontally infected children were serotype F, 1% were serotype B, and the remaining 6% were uninterpretable. In vertically infected children, 74% of strains were serotype F, 10% were serotype A, 3% were serotype B, and 3% were serotype E. Serotype F was also the dominant subtype in adults (68%), but serotypes A, B, C, D and E were also detected. SSEIA gave indeterminate results in 7% of cases. A strong correlation (90%) between serotyping and genotyping for subtype F was found. Analysis of the relative incidence of the different serotypes over a 7-year period (1990-1997) showed a stable distribution. CONCLUSIONS: Subtype F largely dominates the epidemiology of HIV-1 infection in both children and adults in Romania, although other major subtypes are present. The predominance of subtype F in Romania may be a future potential source of HIV-1 variability in Europe.

Adult↗
PubMed1998

Highly sensitive method for amplification of human immunodeficiency virus type 2 DNA.

We evaluated a new human immunodeficiency virus type 2 (HIV-2) DNA amplification strategy based on peripheral blood mononuclear cell long PCR (XL PCR) followed by nested PCR amplification. The primers used were located in the highly conserved long terminal repeat and in the pol regions of the genome. Five primer pairs corresponding to different regions of the HIV-2 env gene were used in the nested step. Samples from 42 patients were tested, which yielded positive amplification with at least two primer pairs in 40 (95%) samples. A primer pair (EB2/EB5) located on the V3 region succeeded in amplifying proviral DNA in 40 samples.

DNA Primers↗
PubMed1998

Line probe assay for detection of human immunodeficiency virus type 1 mutations conferring resistance to nucleoside inhibitors of reverse transcriptase: comparison with sequence analysis.

We compared the line probe assay (LiPA) to sequence analysis for the detection of mutations conferring resistance to nucleoside inhibitors of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT). Plasma samples from 40 patients who had received zidovudine, dideoxyinosine, and dideoxycytosine, alone or in combination, and who were enrolled in the ALTIS 2 clinical trial (lamivudine [3TC] plus stavudine) were tested at enrollment and at week 24. RT PCR products from plasma were used for LiPA, and DNA was used for sequence analysis. LiPA gave uninterpretable results for 8.5% of the analyzed codons corresponding to 63 samples, mainly for codons 41, 69, and 70. Several minor discrepancies between the two methods occurred, mainly due to the ability of LiPA to detect mixed populations while sequence analyses detect a single homogeneous population. LiPA is suitable for detecting mixed populations and easy to implement in clinical laboratories and might be useful for epidemiological surveys of primary HIV-1 resistance.

Anti-HIV Agents↗