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"Oumzil, Hicham"
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Proposal of pharmacophore model for HIV reverse transcriptase inhibitors: Combined mutational effect analysis, molecular dynamics, molecular docking and pharmacophore modeling study
by
Elomari, Nezha
,
Lemrabet, Sanae
,
Filali-Maltouf, Abdelkarim
in
Affinity
,
Antiretroviral agents
,
Antiretroviral drugs
2024
Objectives: Antiretroviral therapy (ART) efficacy is jeopardized by the emergence of drug resistance mutations in HIV, compromising treatment effectiveness. This study aims to propose novel analogs of Effavirenz (EFV) as potential direct inhibitors of HIV reverse transcriptase, employing computer-aided drug design methodologies. Methods: Three key approaches were applied: a mutational profile study, molecular dynamics simulations, and pharmacophore development. The impact of mutations on the stability, flexibility, function, and affinity of target proteins, especially those associated with NRTI, was assessed. Molecular dynamics analysis identified G190E as a mutation significantly altering protein properties, potentially leading to therapeutic failure. Comparative analysis revealed that among six first-line antiretroviral drugs, EFV exhibited notably low affinity with viral reverse transcriptase, further reduced by the G190E mutation. Subsequently, a search for EFV-similar inhibitors yielded 12 promising molecules based on their affinity, forming the basis for generating a pharmacophore model. Results: Mutational analysis pinpointed G190E as a crucial mutation impacting protein properties, potentially undermining therapeutic efficacy. EFV demonstrated diminished affinity with viral reverse transcriptase, exacerbated by the G190E mutation. The search for EFV analogs identified 12 high-affinity molecules, culminating in a pharmacophore model elucidating key structural features crucial for potent inhibition. Conclusion: This study underscores the significance of EFV analogs as potential inhibitors of HIV reverse transcriptase. The findings highlight the impact of mutations on drug efficacy, particularly the detrimental effect of G190E. The generated pharmacophore model serves as a pivotal reference for future drug development efforts targeting HIV, providing essential structural insights for the design of potent inhibitors based on EFV analogs identified in vitro.
Journal Article
Prevalence of HBsAg among Moroccan HIV-1 infected patients and APOBEC3G variant frequencies in HIV-1/HBV co-infection
by
Belbacha, Imane
,
Laboudi, Majda
,
Bensghir, Rajae
in
Adult
,
APOBEC-3G Deaminase - genetics
,
APOBEC3G
2024
Introduction: Human immunodeficiency virus (HIV) / hepatitis B virus (HBV) causes higher rates of liver disease compared to infection with just one virus. Co-infection can accelerate the progression to liver fibrosis or hepatocellular carcinoma and disturb the treatment response. APOBEC3G is a host defense factor which interferes with HIV-1 and HBV. We aimed to determine the prevalence of hepatitis B surface antigen (HBsAg) among HIV-infected patients and seronegative controls, and screen the HIV/HBV population for APOBEC3G variants rs8177832, rs35228531 and rs2294367, previously associated with HIV-1 infection susceptibility in Morocco. Methodology: A case control study was conducted on 404 individuals (204 HIV-infected and 200 eligible blood donors) from April to November 2021. HBsAg was measured on the Roche Cobas e411 automatic analyzer (Roche Diagnostics, Basel, Switzerland) and APOBEC3G polymorphisms were identified using the TaqMan genotyping allelic discrimination method. Fisher Exact test, odds ratio (OR) with 95% confidence interval (CI), and haplotype frequencies were calculated. Results: Of the 204 HIV-1 seropositive patients and 200 controls, 4.9% (95%CI: 2.38-8.83) and 2.50% (95% CI: 0.82-5.74) were HBsAg-positive respectively. There was a significant association between increasing age (> 40 years) and HBV infection among controls (p = 0.04). The distribution of genotypes and alleles frequencies of APOBEC3G variants was heterogenous and five different haplotypes with frequencies ≥ 5% were obtained, of which ACC (rs8177832, rs35228531, rs2294367) was the most prevalent. Conclusions: HBV co-infection is common among HIV-1 infected individuals in Morocco. Efforts should be made to prevent, treat and control HBV transmission in this population.
Journal Article
Quality control and external quality assessment for the independent clinic-based evaluation of point-of-care testing to detect Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis in eight countries
by
Cordioli, Maddalena
,
Toskin, Igor
,
Vargas, Silver
in
Analysis
,
Chlamydia
,
Chlamydia Infections - diagnosis
2024
Background
Sexually transmitted infections caused by
Chlamydia trachomatis
(CT),
Neisseria gonorrhoeae
(NG) and
Trichomonas vaginalis
(TV) remain significant global health problems. The World Health Organization (WHO) has recently conducted a multi-faceted, multi-country validation study (ProSPeRo), which included an evaluation of the Xpert CT/NG and Xpert TV assays on the GeneXpert system (Cepheid, Sunnyvale, Ca., USA) in clinic-based settings across eight countries. To support the study, a training and quality management system was implemented and evaluated.
Methods
A comprehensive training program for the study was developed. Quality control (QC) and external quality assessment (EQA) samples were provided by an accredited quality assurance provider. QC testing was conducted at 14 point-of-care testing (POCT) clinics, while EQA samples were tested by the POCT sites and a reference laboratory supporting each clinic.
Results
For QC testing, concordance with the expected results for CT and NG was > 99% and rates of unsuccessful tests were < 4%. For TV testing, concordance was similar (97%), but rates of unsuccessful tests were high (18%), particularly in the ‘TV negative’ sample. For EQA testing initially conducted in 2018, concordance was 100% for CT and NG, and 90% for TV for the reference laboratory group (which used non-GeneXpert systems). Concordance for the POCT group was also high (> 94%) for all analytes, but this cohort (which used GeneXpert systems) exhibited a high rate of unsuccessful TV tests. All but one of these unsuccessful tests was subcategorised as ‘invalid’.
Conclusions
The high level of concordance for QC and EQA testing confirm that the trained operators at the POC clinical sites were competent to conduct POC testing and that the training and quality systems implemented for the ProSPeRo study were effective. The quality materials used were satisfactory for CT and NG but exhibited poor performance for TV testing on the GeneXpert system. The WHO should continue to work with industry and EQA providers to provide improved materials that are reliable, stable and cost effective for quality management, as it seeks to rollout molecular-based STI POCT in non-laboratory-based settings.
Trial registration
Ethics approval to conduct the ProSPeRo study was granted by the WHO Ethics Review Committee.
Journal Article
External quality assessment to support the WHO ProSPeRo study for the evaluation of two dual HIV/syphilis point-of-care tests in seven countries
by
Sherriff, Nigel
,
Shukla, Mayur R.
,
Toskin, Igor
in
Acquired immune deficiency syndrome
,
Agglutination
,
AIDS
2024
Background
Sexually transmitted infections (STIs) such as syphilis and HIV remain to be a significant public health issue worldwide. Dual rapid point-of-care tests (POCTs) have shown promise for detecting antibodies to HIV and syphilis but have not been fully evaluated in the field. Our study supported the WHO ProSPeRo study on Sexually Transmitted Infection Point-of-Care Testing (STI POCT) by providing external quality assessment (EQA) for HIV and syphilis testing in reference laboratories and their associated clinical sites in seven countries.
Methods
HIV/syphilis serum liquid and dried tube specimen (DTS) panels were prepared by CDC. Liquid panels were distributed to the reference laboratories for three rounds of testing using commercially and locally available laboratory-based serological tests. DTS panels were sent to the clinical testing sites for 8 rounds of POC testing using the Abbott SD BIOLINE HIV/Syphilis Duo test (hereafter referred to as SD BIOLINE) and the Chembio Dual Path Platform (DPP) HIV-Syphilis assay. EQA panels were tested at CDC using the Rapid Plasma Reagin (RPR) test and the
Treponema pallidum
Particle Agglutination assay (TP-PA) for syphilis antibodies. Genetic Systems HIV-1/HIV-2 Plus O EIA, Geenius HIV Supplemental Assay and the Oraquick Advance HIV test were used to detect HIV antibodies in the EQA panels. Results from the reference laboratories and POCT sites were compared to those obtained at the CDC and a percentage agreement was calculated.
Results
Qualitative RPR and TP-PA performed at the reference laboratories demonstrated 95.4–100% agreement with CDC results while quantitative RPR and TP-PA tests demonstrated 87.7% and 89.2% agreement, respectively. A 93.8% concordance rate was observed for qualitative HIV testing in laboratories. EQA testing at clinical sites using dual tests showed 98.7% and 99.1% agreement for detection of HIV antibodies and eight out of 10 sites had > 95.8% agreement for syphilis testing. However, two clinical sites showed only 65.0–66.7% agreement for SD BIOLINE and 84.0–86.7% for DPP, respectively, for syphilis testing.
Conclusions
Overall, laboratories demonstrated high EQA performance in this study. Both HIV/syphilis POCTs gave expected results in the clinic-based evaluations using DTS. However, testing errors were identified in a few testing sites suggesting the necessity for continuous training and monitoring the quality of POC testing.
Journal Article
Independent clinic-based evaluation of point-of-care testing for the screening of Chlamydia trachomatis, Neisseria gonorrhoea and Trichomonas vaginalis in women-at-risk in Australia, Guatemala, Morocco, and South Africa
2024
Background
In 2018, the World Health Organization commenced a multi-country validation study of the Cepheid GeneXpert for a range of molecular-based point-of-care (POC) tests in primary care settings. One study arm focused on the evaluation of POC tests for screening ‘women at risk’ for chlamydia (CT), gonorrhoea (NG) and trichomonas (TV) in four countries – Australia, Guatemala, Morocco and South Africa.
Methods
Study participants completed a pre-test questionnaire which included demographics, clinical information and general questions on POC testing (POCT). Two vaginal swab samples (either self-collected or clinician collected) from each patient were tested on the GeneXpert at the POC and at a reference laboratory using quality-assured nucleic acid amplification tests (NAATs).
Results
One thousand three hundred and eighty-three women were enrolled: 58.6% from South Africa, 29.2% from Morocco, 6.2% from Guatemala, and 6.0% from Australia. 1296 samples for CT/NG and 1380 samples for TV were tested by the GeneXpert and the reference NAAT. The rate of unsuccessful tests on the GeneXpert was 1.9% for CT, 1.5% for NG and 0.96% for TV. The prevalence of CT, NG and TV was 31%, 13% and 23%, respectively. 1.5% of samples were positive for all three infections; 7.8% were positive for CT and NG; 2.4% were positive for NG and TV; and 7.3% were positive for CT and TV. Compared to reference NAATs, pooled estimates of sensitivity for the GeneXpert tests were 83.7% (95% confidence intervals 69.2-92.1) for CT, 90.5% (85.1-94.1) for NG and 64.7% (58.1-70.7) for TV (although estimates varied considerably between countries). Estimates for specificity were ≥96% for all three tests both within- and between-countries. Pooled positive and negative likelihood ratios were: 32.7 ([CI] 21.2-50.5) and 0.17 (0.08-0.33) for CT; 95.3 (36.9-245.7) and 0.10 (0.06-0.15) for NG; and 56.5 (31.6-101.1) and 0.35 (0.27-0.47) for TV.
Conclusion
This multi-country evaluation is the first of its kind world-wide. Positive likelihood ratios, as well as specificity estimates, indicate the GeneXpert POC test results for CT, NG and TV were clinically acceptable for ruling in the presence of disease. However, negative likelihood ratios and variable sensitivity estimates from this study were poorer than expected for ruling out these infections, particularly for TV.
Trial registration
Ethics approval to conduct the ProSPeRo study was granted by the WHO Ethics Review Committee, as well as local ethics committees from all participating countries.
Journal Article
Establishing seasonal and alert influenza thresholds in Morocco
by
McCarron, Margaret
,
Regragui, Zakia
,
Triki, Soumia
in
Alert threshold
,
Average epidemic curve
,
Biostatistics
2020
Background
Several statistical methods of variable complexity have been developed to establish thresholds for influenza activity that may be used to inform public health guidance. We compared the results of two methods and explored how they worked to characterize the 2018 influenza season performance–2018 season.
Methods
Historical data from the 2005/2006 to 2016/2018 influenza season performance seasons were provided by a network of 412 primary health centers in charge of influenza like illness (ILI) sentinel surveillance. We used the WHO averages and the moving epidemic method (MEM) to evaluate the proportion of ILI visits among all outpatient consultations (ILI%) as a proxy for influenza activity. We also used the MEM method to evaluate three seasons of composite data (ILI% multiplied by percent of ILI with laboratory-confirmed influenza) as recommended by WHO.
Results
The WHO method estimated the seasonal ILI% threshold at 0.9%. The annual epidemic period began on average at week 46 and lasted an average of 18 weeks. The MEM model estimated the epidemic threshold (corresponding to the WHO seasonal threshold) at 1.5% of ILI visits among all outpatient consultations. The annual epidemic period began on week 49 and lasted on average 14 weeks. Intensity thresholds were similar using both methods. When using the composite measure, the MEM method showed a clearer estimate of the beginning of the influenza epidemic, which was coincident with a sharp increase in confirmed ILI cases.
Conclusions
We found that the threshold methodology presented in the WHO manual is simple to implement and easy to adopt for use by the Moroccan influenza surveillance system. The MEM method is more statistically sophisticated and may allow a better detection of the start of seasonal epidemics. Incorporation of virologic data into the composite parameter as recommended by WHO has the potential to increase the accuracy of seasonal threshold estimation.
Journal Article
Pre-pandemic antibodies screening against SARS-CoV-2 and virus detection among children diagnosed with eruptive fevers
by
El Hassani, Rabii Ameziane
,
Ait-Lhaj-Mhand, Rokaya
,
Kadi, Chaimae
in
Adolescent
,
Antibodies
,
Antibodies, Neutralizing - blood
2024
Objectives
This study aims to assess the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibodies against the spike (S) and nucleocapsid (NP) proteins, as well as neutralizing antibodies against the receptor-binding domain (RBD). Additionally, it aims to detect viral RNA of SARS-CoV-2 in pre-pandemic archival pediatric specimens collected before the announcement of the COVID-19 pandemic spread on March 20th, 2020, in Morocco. The objective is to investigate the existence of pre-pandemic immunity to SARS-CoV-2.
Methods
We conducted a cross-sectional study, to analyze IgG antibody levels in a cohort of 106 pre-pandemic pediatric participants. Using an indirect enzyme-linked immunosorbent assay (ELISA), we measured the IgG levels against the S and NP proteins of SARS-CoV-2. Additionally, we staged a competitive ELISA assay to evaluate the neutralizing capability of these antibodies. We used reverse transcription polymerase chain reaction (rRT-PCR) to detect viral NP and ORF1ab genes of SARS-CoV-2 in oropharyngeal swabs. Moreover, we conducted on the same specimens a multiplexed RT-PCR to detect RNA of the most common 27 pathogens involved in lower respiratory tract infections.
Results
Among the 106 serum samples, 13% (nn = =14) tested positive for SARS-CoV-2 IgG antibodies using ELISA. Temporal analysis indicated varying IgG positivity levels across 2019. Neutralizing antibodies were found in 21% of the 28 samples analyzed, including two with high inhibition rates (93%). The SARS-CoV-2 RNA was detected using rRT-PCR in 14 samples. None of the samples tested positive for the other 27 pathogens associated with lower respiratory tract infections, using multiplexed RT-PCR.
Conclusion
Our study addresses the possibility, that COVID-19 infections occurred in Morocco before the recognized outbreak. On the other hand, some of the cases might reflect cross-reactivity with other coronaviruses or be influenced by previous viral exposures or vaccinations. Understanding these factors is crucial to comprehending pediatric immune responses to newly emerging infectious diseases.
Journal Article
Factors associated with hospitalization for seasonal influenza in Morocco
2023
Background: Morocco is actively working towards expanding its influenza vaccine policy to cover high-risk groups, as recommended by the World Health Organization (WHO). Aims: We assessed the risk factors for influenza-associated hospitalization for severe acute respiratory infections (SARI) that occurred during the last 5 seasons. Methods: We conducted a retrospective, analytical study among patients recruited in the ambulatory and hospital sites of the influenza sentinel surveillance system in Morocco between 2014 and 2019. Using multiple logistic regression, we compared the characteristics of influenza-positive patients with SARI to those with influenza-like illness (ILI) to identify factors associated with severe disease. Results: We included 1323 positive influenza patients with either SARI (41.7%) or ILI diagnosis (58.3%). A(H1N1)pdm09, A(H3N2) and influenza B, respectively, contributed 49.2%, 29.5% and 20.6% of the cases. The main risk factors considered in the bivariate analysis were found in the multivariate analysis to be significantly associated with influenza-related hospitalization (SARI): age < 2 years (aOR = 7.08, P < 0.001); age ≥ 65 years (aOR = 3.59, P < 0.001); diabetes (aOR = 1.98, P = 0.017); obesity (aOR = 2.94, P = 0.034); asthma or chronic respiratory disease (aOR = 4.99, P < 0.001); chronic renal failure (aOR = 4.74, P = 0.005); pregnancy (aOR = 7.49, P < 0.001); and the A(H1N1)pdm09 subtype (aOR = 1.82, P < 0.001). Conclusion: This study provides epidemiological evidence for the expected benefit of an influenza vaccination strategy for high-risk groups as recommended by the WHO.
Journal Article
Assessment of the HBV vaccine response in a group of HIV-infected children in Morocco
by
Haban, Houda
,
Benjouad, Abdelaziz
,
Amzazi, Said
in
Acquired immune deficiency syndrome
,
AIDS
,
Antibodies
2017
Background
Since its development in the early 1980s, Hepatitis B virus (HBV) vaccine has been proven to be highly protective. However, its immunogenicity may be ineffective among HIV-infected children. In Morocco, HBV vaccine was introduced in 1999, and since then all infants, including vertically HIV-infected infants, have been following the vaccination schedule, implemented by the Moroccan ministry of health. An assessment of the immunization of these children is important to optimize efforts aimed at tackling Hepatitis B coinfection, within the country.
Methods
Forty-nine HIV-infected children (HIV group) and 112 HIV uninfected children (control group) were enrolled in this study. Samples were tested by Elisa (Monolisa Anti-HBs, Biorad) to quantify the anti-HBs antibodies. The % of lymphocyte subsets i.e. CD4+ T cells, CD8+ T cells, B cells, and NK, was determined by flow cytometry, using CellQuest Pro software (Becton-Dickinson), and for HIV group, HIV viral load was measured by real time PCR assay (Abbott). All variables were statistically compared in the two groups.
Results
The median age was 51 ± 35 months for the HIV group and 50 ± 36 months (
p
> 0.05) for the control group. Female represented 63% and 41% (
p
= 0.01), among the HIV group and the control group, respectively. Among HIV-infected children, 71.4% (35/49) were under HAART therapy at the enrollment in the study. Seroprotection titer i.e. anti-HBs ≥10mUI/ml among control group was 76% (85/112), and only 29% (14/49) among the perinatally HIV-infected children (
p
< 0.0001). Lower % of CD4 + T cells was observed in HIV-infected children with a poor anti-HBs response.
Conclusion
In this studied group, we have shown that despite the vaccination of HIV-children with HBV vaccine, 71% did not show any seroprotective response. These findings support the need for monitoring HBV vaccine response among HIV-infected children in Morocco, in order to revaccinate non-immunized children.
Journal Article
Seroprevalence of measles vaccine antibody response in vertically HIV-infected children, in Morocco
by
Haban, Houda
,
Ahmed, Hinda Jama
,
Benjouad, Abdelaziz
in
Antibodies
,
Antibodies, Viral - blood
,
Antibody Formation
2018
Background
The widespread use of an effective and safe vaccine to measles has substantially decreased morbidity and mortality from this epidemic. Nevertheless, HIV-infected children vaccinated against measles may develop an impaired vaccine response and remain susceptible to this disease. In Morocco, infants are routinely vaccinated against measles, regardless of their HIV serostatus. An evaluation of the immunization of these children may be of paramount importance to implement timely measures aimed at preventing measles transmission.
Methods
In this study, we have enrolled 114 children vaccinated against measles, 50 children prenatally infected with HIV and 64 HIV-uninfected children. For all children, blood samples were taken to measure anti-measles IgG by EIA and CD4 count by flow cytometry. Additionally, HIV viral load was determined by automated real time PCR, for HIV-infected children.
Results
The seroprotective rate of IgG anti-measles antibodies was significantly lower among HIV-infected children (26%) compared with HIV-uninfected children (73%) (
p
< 0.001). Within HIV-infected children group, the comparison of variables between children without seroprotective seroconversion to measles and those with seroprotective immunity, displayed that sex and age were not statistically different,
p
> 0.999 and
p
= 0.730, respectively. However, CD4 count was lower among children with negative serostatus to measles (23% versus 32%,
p
< 0.001). Furthermore, viral load was higher, with 2.91 log
10
± 2.24 versus 1.7 log
10
± 1.5 (
p
= 0.042). Finally, 62% of children with a negative vaccine response to measles were under HAART therapy, versus 92% (
p
= 0.008).
Conclusion
The majority of HIV-infected children vaccinated against measles develop a suboptimal seroprotective titer, and therefore remain at risk for this highly infectious disease. These data in combination with international recommendations, including recent WHO guidance on vaccination of HIV-infected children, suggest there is a need for national measures to prevent these children from measles.
Journal Article