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1.
J Antimicrob Chemother ; 79(5): 1164-1168, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38546752

ABSTRACT

OBJECTIVES: Integrase strand transfer inhibitors (INSTIs) have been recently recommended as the preferred first-line option for antiretroviral treatment initiators in low- and middle-income countries (LMICs) in response to the growing circulation of resistant HIV to non-nucleoside reverse transcriptase inhibitors (NNRTIs). In this study, we estimated the frequency of pretreatment drug resistance (PDR) to INSTIs in West Africa and Southeast Asia. MATERIALS AND METHODS: Using samples collected from 2015 to 2016, and previously used to assessed PI, NRTI and NNRTI resistance, we generated HIV integrase sequences and identified relevant INSTI PDR mutations using the Stanford and ANRS algorithms. RESULTS: We generated 353 integrase sequences. INSTI PDR frequency was low, 1.1% (4/353) overall, ranging from 0% to 6.3% according to country. However, frequency of PDR to any drug class was very high, 17.9% (95% CI: 13.9%-22.3%), and mostly associated with a high level of NNRTI PDR, 9.7%, and a moderate level of NRTI PDR, 5.3%. CONCLUSIONS: Our results support the recent introduction of INSTIs in LMICs to improve treatment outcome in these settings, but also stress the need for effective actions to prevent uncontrolled emergence of drug resistance to this drug class.


Subject(s)
Drug Resistance, Viral , HIV Infections , HIV Integrase Inhibitors , HIV Integrase , HIV-1 , Humans , Africa, Western/epidemiology , Asia, Southeastern/epidemiology , Drug Resistance, Viral/genetics , HIV Infections/drug therapy , HIV Infections/virology , HIV Infections/epidemiology , HIV Integrase/genetics , HIV Integrase Inhibitors/pharmacology , HIV Integrase Inhibitors/therapeutic use , HIV-1/drug effects , HIV-1/genetics , Mutation , Prevalence
2.
Electrophoresis ; 45(5-6): 557-572, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38161236

ABSTRACT

We explore a bioinspired approach to design tailored functionalized capillary electrophoresis (CE) surfaces based on covalent grafting for biomolecules analysis. First, the approach aims to overcome well-known common obstacles in CE protein analysis affecting considerably the CE performance (asymmetry, resolution, and repeatability) such as the unspecific adsorption on fused silica surface and the lack of control of electroosmotic flow (EOF). Then, our approach, which relies on new amino-amide mimic hybrid precursors synthesized by silylation of amino-amides (Si-AA) derivatives with 3-isocyanatopropyltriethoxysilane, aims to recapitulate the diversity of protein-protein interactions (π-π stacking, ionic, Van der Waals…) found in physiological condition (bioinspired approach) to improve the performance of CE protein analysis (electrochromatography). As a proof of concept, these silylated Si-AA (tyrosinamide silylation, serinamide silylation, argininamide silylation, leucinamide silylation, and isoglutamine silylation acid) have been covalently grafted in physiological conditions in different amount on bare fused silica capillary giving rise to a biomimetic coating and allowing both the modulation of EOF and protein-surface interactions. The analytical performances of amino-amide functionalized capillaries were assessed using lysozyme, cytochrome C and ribonuclease A and compared to traditional capillary coatings poly(ethylene oxide), poly(diallyldimethylammonium chloride), and sodium poly(styrenesulfonate). EOF, protein adsorption rate, protein retention factor k, and selectivity were determined for each coating. All results obtained showed this approach allowed to modulate the EOF, reduce unspecific adsorption, and generate specific interactions with proteins by varying the nature and the amount of Si-AA in the functionalization mixture.


Subject(s)
Amides , Electroosmosis , Electrophoresis, Capillary/methods , Polyethylene Glycols/chemistry , Proteins , Silicon Dioxide/chemistry
3.
J Antimicrob Chemother ; 77(4): 1111-1118, 2022 03 31.
Article in English | MEDLINE | ID: mdl-35045168

ABSTRACT

BACKGROUND: Data evaluating the risk of proximal tubular dysfunction in women receiving tenofovir disoproxil fumarate for the prevention of mother-to-child transmission (PMTCT) of HBV are scarce. OBJECTIVES: To assess the risk of proximal tubulopathy in pregnant women receiving tenofovir disoproxil fumarate for PMTCT of HBV. PATIENTS AND METHODS: We used urine samples collected from HBV monoinfected pregnant women who participated in a Phase III, multicentre, randomized, double-blind, placebo-controlled clinical trial assessing a tenofovir disoproxil fumarate short course from 28 weeks gestational age (28-wk-GA) to 2 months post-partum (2-months-PP) for PMTCT of HBV in Thailand. Markers of tubular dysfunction, including retinol binding protein, kidney injury molecule-1, α1-microglobuin and ß2-microglobulin, were assayed at 28- and 32-wk-GA and 2-months-PP visits. Proximal tubulopathy was defined as the presence of ≥2 of the following: tubular proteinuria, euglycaemic glycosuria and increased urinary phosphate. RESULTS: A total of 291 women participated in the study. No kidney-related adverse events were severe, and none led to tenofovir disoproxil fumarate discontinuation. At 2-months-PP, 3 of the 120 (3%) evaluated women in the tenofovir disoproxil fumarate group experienced proximal tubulopathy versus 3 of 125 (2%) in the placebo group (P = 1.00). None of the six women met the criteria for proximal tubulopathy at 12-months-PP but proteinuria persisted in three of them. No growth abnormalities were found at 1 year of age in infants born to mothers with proximal tubulopathy at 2-months-PP. CONCLUSIONS: In these HBV-infected pregnant and breastfeeding women, tenofovir disoproxil fumarate administered from 28-wk-GA to 2-months-PP was not associated with a higher risk of proximal tubulopathy.


Subject(s)
Hepatitis B virus , Pregnancy Complications, Infectious , Antiviral Agents/therapeutic use , Child, Preschool , Female , Humans , Infant , Infectious Disease Transmission, Vertical/prevention & control , Pregnancy , Pregnancy Complications, Infectious/drug therapy , Pregnancy Complications, Infectious/prevention & control , Pregnant Women , Tenofovir/adverse effects
4.
Molecules ; 27(8)2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35458758

ABSTRACT

Herpes simplex type 2 (HSV-2) infection causes a significant life-long disease. Long-term side effects of antiviral drugs can lead to the emergence of drug resistance. Thus, propolis, a natural product derived from beehives, has been proposed to prevent or treat HSV-2 infections. Unfortunately, therapeutic applications of propolis are still limited due its poor solubility. To overcome this, a nanoparticle-based drug delivery system was employed. An ethanolic extract of propolis (EEP) was encapsulated in nanoparticles composed of poly(lactic-co-glycolic acid) and chitosan using a modified oil-in-water single emulsion by using the solvent evaporation method. The produced nanoparticles (EEP-NPs) had a spherical shape with a size of ~450 nm and presented satisfactory physicochemical properties, including positively charged surface (38.05 ± 7.65 mV), high entrapment efficiency (79.89 ± 13.92%), and sustained release profile. Moreover, EEP-NPs were less cytotoxic on Vero cells and exhibited anti-HSV-2 activity. EEP-NPs had a direct effect on the inactivation of viral particles, and also disrupted the virion entry and release from the host cells. A significant decrease in the expression levels of the HSV-2 replication-related genes (ICP4, ICP27, and gB) was also observed. Our study suggests that EEP-NPs provide a strong anti-HSV-2 activity and serve as a promising platform for the treatment of HSV-2 infections.


Subject(s)
Herpes Simplex , Nanoparticles , Propolis , Animals , Chlorocebus aethiops , Herpes Simplex/drug therapy , Herpesvirus 2, Human , Propolis/chemistry , Vero Cells
5.
J Bacteriol ; 203(4)2021 01 25.
Article in English | MEDLINE | ID: mdl-33257527

ABSTRACT

The outer membrane of Gram-negative bacteria acts as an initial diffusion barrier that shields the cell from the environment. It contains many membrane-embedded proteins required for functionality of this system. These proteins serve as solute and lipid transporters or as machines for membrane insertion or secretion of proteins. The genome of Anabaena sp. strain PCC 7120 codes for two outer membrane transporters termed TpsB1 and TpsB2. They belong to the family of the two-partner secretion system proteins which are characteristic of pathogenic bacteria. Because pathogenicity of Anabaena sp. strain PCC 7120 has not been reported, the function of these two cyanobacterial TpsB proteins was analyzed. TpsB1 is encoded by alr1659, while TpsB2 is encoded by all5116 The latter is part of a genomic region containing 11 genes encoding TpsA-like proteins. However, tpsB2 is transcribed independently of a tpsA gene cluster. Bioinformatics analysis revealed the presence of at least 22 genes in Anabaena sp. strain PCC 7120 putatively coding for substrates of the TpsB system, suggesting a rather global function of the two TpsB proteins. Insertion of a plasmid into each of the two genes resulted in altered outer membrane integrity and antibiotic resistance. In addition, the expression of genes coding for the Clp and Deg proteases is dysregulated in these mutants. Moreover, for two of the putative substrates, a dependence of the secretion on functional TpsB proteins could be confirmed. We confirm the existence of a two-partner secretion system in Anabaena sp. strain PCC 7120 and predict a large pool of putative substrates.IMPORTANCE Cyanobacteria are important organisms for the ecosystem, considering their contribution to carbon fixation and oxygen production, while at the same time some species produce compounds that are toxic to their environment. As a consequence, cyanobacterial overpopulation might negatively impact the diversity of natural communities. Thus, a detailed understanding of cyanobacterial interaction with the environment, including other organisms, is required to define their impact on ecosystems. While two-partner secretion systems in pathogenic bacteria are well known, we provide a first description of the cyanobacterial two-partner secretion system.


Subject(s)
Anabaena/genetics , Anabaena/metabolism , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Gram-Negative Bacteria/metabolism , Anabaena/growth & development , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Secretion Systems/genetics , Bacterial Secretion Systems/metabolism , Biological Transport , Cyanobacteria , Drug Resistance, Microbial , Gene Expression Regulation, Bacterial , Genome, Bacterial , Glucosyltransferases , Membrane Transport Proteins/genetics , Type V Secretion Systems/metabolism
6.
N Engl J Med ; 378(10): 911-923, 2018 Mar 08.
Article in English | MEDLINE | ID: mdl-29514030

ABSTRACT

BACKGROUND: Pregnant women with an elevated viral load of hepatitis B virus (HBV) have a risk of transmitting infection to their infants, despite the infants' receiving hepatitis B immune globulin. METHODS: In this multicenter, double-blind clinical trial performed in Thailand, we randomly assigned hepatitis B e antigen (HBeAg)-positive pregnant women with an alanine aminotransferase level of 60 IU or less per liter to receive tenofovir disoproxil fumarate (TDF) or placebo from 28 weeks of gestation to 2 months post partum. Infants received hepatitis B immune globulin at birth and hepatitis B vaccine at birth and at 1, 2, 4, and 6 months. The primary end point was a hepatitis B surface antigen (HBsAg)-positive status in the infant, confirmed by the HBV DNA level at 6 months of age. We calculated that a sample of 328 women would provide the trial with 90% power to detect a difference of at least 9 percentage points in the transmission rate (expected rate, 3% in the TDF group vs. 12% in the placebo group). RESULTS: From January 2013 to August 2015, we enrolled 331 women; 168 women were randomly assigned to the TDF group and 163 to the placebo group. At enrollment, the median gestational age was 28.3 weeks, and the median HBV DNA level was 8.0 log10 IU per milliliter. Among 322 deliveries (97% of the participants), there were 319 singleton births, two twin pairs, and one stillborn infant. The median time from birth to administration of hepatitis B immune globulin was 1.3 hours, and the median time from birth to administration of hepatitis B vaccine was 1.2 hours. In the primary analysis, none of the 147 infants (0%; 95% confidence interval [CI], 0 to 2) in the TDF group were infected, as compared with 3 of 147 (2%; 95% CI, 0 to 6) in the placebo group (P=0.12). The rate of adverse events did not differ significantly between groups. The incidence of a maternal alanine aminotransferase level of more than 300 IU per liter after discontinuation of the trial regimen was 6% in the TDF group and 3% in the placebo group (P=0.29). CONCLUSIONS: In a setting in which the rate of mother-to-child HBV transmission was low with the administration of hepatitis B immune globulin and hepatitis B vaccine in infants born to HBeAg-positive mothers, the additional maternal use of TDF did not result in a significantly lower rate of transmission. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT01745822 .).


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B virus/isolation & purification , Hepatitis B/transmission , Infectious Disease Transmission, Vertical/prevention & control , Pregnancy Complications, Infectious/drug therapy , Tenofovir/therapeutic use , Adolescent , Adult , Alanine Transaminase/blood , Antiviral Agents/adverse effects , DNA, Viral/isolation & purification , Double-Blind Method , Female , Hepatitis B/diagnosis , Hepatitis B/drug therapy , Hepatitis B Vaccines , Hepatitis B e Antigens/blood , Hepatitis B virus/genetics , Humans , Infant , Infant, Newborn , Male , Pregnancy , Tenofovir/adverse effects , Viral Load , Young Adult
7.
Molecules ; 26(19)2021 Oct 08.
Article in English | MEDLINE | ID: mdl-34641630

ABSTRACT

Ordered mesoporous materials and their modification with multiple functional groups are of wide scientific interest for many applications involving interaction with biological systems and biomolecules (e.g., catalysis, separation, sensor design, nano-science or drug delivery). In particular, the immobilization of enzymes onto solid supports is highly attractive for industry and synthetic chemistry, as it allows the development of stable and cheap biocatalysts. In this context, we developed novel silylated amino acid derivatives (Si-AA-NH2) that have been immobilized onto SBA-15 materials in biocompatible conditions avoiding the use of toxic catalyst, solvents or reagents. The resulting amino acid-functionalized materials (SBA-15@AA) were characterized by XRD, TGA, EA, Zeta potential, nitrogen sorption and FT-IR. Differences of the physical properties (e.g., charges) were observed while the structural ones remained unchanged. The adsorption of the enzyme lysozyme (Lyz) onto the resulting functionalized SBA-15@AA materials was evaluated at different pHs. The presence of different functional groups compared with bare SBA-15 showed better adsorption results, for example, 79.6 nmol of Lyz adsorbed per m2 of SBA-15@Tyr compared with the 44.9 nmol/m2 of the bare SBA-15.


Subject(s)
Amino Acids/chemistry , Muramidase/chemistry , Silicon Dioxide/chemistry , Adsorption , Enzymes, Immobilized/chemistry , Hydrogen-Ion Concentration , Molecular Structure , Porosity , Spectroscopy, Fourier Transform Infrared , Surface Properties
8.
Mol Microbiol ; 111(5): 1302-1316, 2019 05.
Article in English | MEDLINE | ID: mdl-30742726

ABSTRACT

ß-barrel-shaped outer membrane proteins (OMPs) ensure regulated exchange of molecules across the cell-wall of Gram-negative bacteria. They are synthesized in the cytoplasm and translocated across the plasma membrane via the SEC translocon. In the periplasm, several proteins participate in the transfer of OMPs to the outer membrane-localized complex catalyzing their insertion. This process has been described in detail for proteobacteria and some molecular components are conserved in cyanobacteria. For example, Omp85 proteins that catalyze the insertion of OMPs into the outer membrane exist in cyanobacteria as well. In turn, SurA and Skp involved in OMP transfer from plasma membrane to Omp85 in E. coli are likely replaced by Tic22 in cyanobacteria. We describe that anaTic22 functions as periplasmic holdase for OMPs in Anabaena sp. PCC 7120 and provide evidence for the process of substrate delivery to anaOmp85. AnaTic22 binds to the plasma membrane with specificity for phosphatidylglycerol and monogalactosyldiacylglycerol. Substrate recognition induces membrane dissociation and interaction with the N-terminal POTRA domain of Omp85. This leads to substrate release by the interaction with a proline-rich domain and the first POTRA domain of Omp85. The order of events during OMP transfer from plasma membrane to Omp85 in cyanobacteria is discussed.


Subject(s)
Anabaena/enzymology , Bacterial Outer Membrane Proteins/metabolism , Membrane Transport Proteins/metabolism , Bacterial Outer Membrane Proteins/genetics , Cell Membrane/physiology , Membrane Transport Proteins/genetics , Models, Molecular , Protein Biosynthesis , Protein Transport
9.
Protein Expr Purif ; 175: 105689, 2020 11.
Article in English | MEDLINE | ID: mdl-32698044

ABSTRACT

Lipopolysaccharides are central elements of the outer leaflet of the outer membrane of Gram-negative bacteria and as such, of cyanobacteria. In the past, the structural analysis of the system in proteobacteria like Escherichia coli has contributed to a deep understanding of the transport of lipopolysaccharides from plasma membrane to the outer membrane. While many components of the transport system are conserved between proteobacteria and cyanobacteria, the periplasmic LptC appears to be distinct. The cyanobacterial proteins are twice as long as the proteobacterial proteins or proteins from firmicutes. This prompted the question whether the structure of the cyanobacterial proteins is comparable the one of the proteobacterial proteins. To address this question, we expressed LptC from Anabaena sp. PCC 7120 in E. coli as truncated protein without the transmembrane segment. We purified the protein utilizing HIS-tag based affinity chromatography and polished the protein after removal of the tag by size exclusion chromatography. The purified recombinant protein was crystallized by the sitting-drop vapor diffusion technique and best crystals, despite being twinned, diffracted to a resolution of 2.6 Å.


Subject(s)
Anabaena/genetics , Gene Expression , Periplasmic Proteins , Crystallography, X-Ray , Periplasmic Proteins/biosynthesis , Periplasmic Proteins/chemistry , Periplasmic Proteins/genetics , Periplasmic Proteins/isolation & purification , Protein Domains , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification
10.
AIDS Behav ; 24(5): 1505-1516, 2020 May.
Article in English | MEDLINE | ID: mdl-31605294

ABSTRACT

Systematic face-to-face pre-HIV test counseling is costly and may discourage clients to present for regular testing. In a randomized, controlled, non-inferiority trial conducted in four facilities providing free-of-charge anonymous HIV testing in Thailand, participants received either: standard counseling according to national guidelines (reference); computer-assisted counseling: interactive counseling on a tablet computer followed by an invitation to ask questions to the counselor; or on-demand counseling: invitation to ask questions to the counselor. Primary endpoint was a HIV retest within 7 months after enrolment visit. Following the planned interim analysis, on-demand counseling was discontinued for futility. In the final analysis in 1036 HIV-uninfected at-risk participants, computer-assisted counseling was non-inferior to standard counseling and had similar acceptability and improvements in HIV knowledge and sexual risk behaviors; however, it significantly reduced the time spent by counselors on counseling. Implementation of pre-HIV test computer-assisted counseling may ease the burden on staff involved in HIV testing.


Subject(s)
HIV Infections , Counseling , HIV Infections/diagnosis , HIV Infections/prevention & control , Humans , Risk-Taking , Sexual Behavior , Thailand
11.
Clin Infect Dis ; 69(1): 144-146, 2019 06 18.
Article in English | MEDLINE | ID: mdl-30924492

ABSTRACT

In a randomized, double-blind, placebo-controlled trial of tenofovir disoproxil fumarate (TDF) use from 28 weeks gestational age to 2 months postpartum to prevent mother-to-child transmission of hepatitis B virus, there was no significant effect of maternal TDF use on maternal or infant bone mineral density 1 year after delivery/birth. Clinical Trials Registration. NCT01745822.


Subject(s)
Antiviral Agents/therapeutic use , Bone Density/drug effects , Hepatitis B/drug therapy , Infectious Disease Transmission, Vertical/prevention & control , Tenofovir/therapeutic use , Adult , Double-Blind Method , Female , Gestational Age , Hepatitis B virus , Humans , Infant , Male , Postpartum Period , Pregnancy , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Infectious/virology , Viral Load/drug effects , Young Adult
12.
J Antimicrob Chemother ; 74(2): 462-467, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30418575

ABSTRACT

Background: ART in the developing world has moved to a new era with the WHO recommendation to test and immediately treat HIV-positive individuals. A high frequency of pretreatment HIV drug resistance (PDR) can compromise ART efficacy. Our study presents updated estimates of PDR in seven countries from West Africa (Burkina Faso, Cameroon, Côte d'Ivoire, Mali and Togo) and Southeast Asia (Thailand and Vietnam). Methods: Eligible study participants were adult ART initiators, recruited from December 2015 to November 2016 in major ART clinics in each country. HIV drug resistance (HIVDR) tests were performed for all specimens and interpretation was done using the Stanford algorithm. Results: Overall, 1153 participants were recruited and 1020 nt sequences were generated. PDR frequency among all initiators was 15.9% (95% CI: 13.8%-18.3%) overall, ranging from 9.6% and 10.2% in Burkina Faso and Thailand, respectively, 14.7% in Vietnam, 15.4% in Mali, 16.5% in Côte d'Ivoire and 19.3% in Cameroon, to 24.6% in Togo. The prevalence of NNRTI resistance mutations was 12%; NRTI and PI PDR prevalences were 4% and 3%, respectively. Conclusions: Our study shows that in most countries PDR exceeded 10%, warranting the conduct of nationally representative surveys to confirm this trend. In the meantime, actions to prevent drug resistance, including transition from NNRTIs to more robust drug classes should be urgently implemented.


Subject(s)
Drug Resistance, Viral/genetics , HIV Infections/epidemiology , HIV-1/drug effects , Adult , Africa, Western/epidemiology , Anti-HIV Agents/blood , Asia, Southeastern/epidemiology , Female , HIV-1/genetics , Humans , Male , Middle Aged , Prevalence , Viral Load
13.
Magn Reson Med ; 81(3): 1645-1658, 2019 03.
Article in English | MEDLINE | ID: mdl-30387905

ABSTRACT

PURPOSE: Quantitative susceptibility mapping (QSM) provides information about tissue composition and organization. However, current acquisition methods can be quite time consuming, limiting the use of QSM in studies and in monitoring dynamic events. In this work, time efficient spiral acquisitions are combined with a model-based image reconstruction approach. Magnetic field inhomogeneity artifacts are corrected to obtain full brain susceptibility maps. METHODS: Magnetic field maps, capturing the magnetic field inhomogeneity distribution due to non-tissue sources (background field), were estimated from a calibration scan. Tissue phase information present in the background field maps was identified using variable spherical mean value filtering and removed from the estimated field maps. The resulting background field maps were then used in the image reconstruction to correct the magnetic field inhomogeneity artifacts. Images were acquired on a 3 T system with a 3D spiral-in acquisition based on a rotated stack of spirals. For comparison, standard gradient echo images were also acquired. Susceptibility maps were obtained for both acquisitions using a dipole inversion algorithm based on a compressed sensing compensated formulation with wavelet and total variation penalties. RESULTS: Susceptibility maps obtained with the spiral acquisition and the model-based reconstruction agree with the ones obtained with the spin-warp gradient echo acquisition. Using the 3D spiral acquisition, full brain susceptibility maps at the resolution of 1 mm isotropic are obtained in 23 s CONCLUSIONS: Image distortions and blurring due to magnetic field inhomogeneity are removed while maintaining tissue magnetic susceptibility information, resulting in QSM maps in much shorter acquisition time.


Subject(s)
Brain/diagnostic imaging , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Fields , Magnetic Resonance Imaging , Adult , Algorithms , Artifacts , Brain Mapping/methods , Calibration , Female , Healthy Volunteers , Humans , Image Interpretation, Computer-Assisted/methods , Male , Signal-To-Noise Ratio , Wavelet Analysis
14.
J Med Virol ; 91(9): 1652-1659, 2019 09.
Article in English | MEDLINE | ID: mdl-31095748

ABSTRACT

In settings where plasma preparation and sample centralization are not feasible or inconvenient, dried blood spots (DBS) could be used as an alternative specimen to plasma to assess antiretroviral treatment response among HIV-infected individuals. This study was aimed to (1) validate the recent QIAsymphony-artus assay for DBS HIV viral load (VL) and (2) assess the feasibility of measuring HIV VL on DBS using this assay in Thailand. Ethylenediaminetetraacetic acid-blood samples from 99 HIV-infected individuals were used to prepare paired DBS and plasma. Also, DBS samples were shipped to three distant hospitals in the northern region. After short-term storage, DBS were returned by regular post to the AMS laboratory and were re-tested for HIV VL using the same platform. HIV VL results were compared using Pearson's correlation and Bland-Altman analysis. DBS HIV VL fairly correlated to plasma HIV VL (R = 0.62) with a mean difference of 0.02 log10 IU/mL (SD = 1.06). A high correlation (R = 0.79) was observed between HIV VL in DBS before and after shipping (mean difference = 0.14 log10 IU/mL, SD = 0.74), indicating good stability of HIV RNA in DBS. DBS can be used as an alternative specimen for HIV VL monitoring in Thailand. However, measurement of HIV VL with the QIAGEN QIAsymphony-artus assay should be improved, especially the DBS pre-extraction process.


Subject(s)
Dried Blood Spot Testing , HIV Infections/diagnosis , HIV Infections/virology , HIV-1/genetics , Reagent Kits, Diagnostic , Viral Load/methods , Biomarkers , CD4 Lymphocyte Count , Dried Blood Spot Testing/methods , Dried Blood Spot Testing/standards , Female , Humans , Male , RNA, Viral , Sensitivity and Specificity , Thailand , Viral Load/standards
15.
BMC Pediatr ; 19(1): 287, 2019 08 17.
Article in English | MEDLINE | ID: mdl-31421667

ABSTRACT

BACKGROUND: Antiretroviral treatment (ART) has been shown to have a beneficial effect on the weight evolution but its effect on height remains unclear. We described patterns of height evolution and identified predictors of catch-up growth in HIV-infected children on ART. METHODS: To describe the height evolution from birth to adulthood, we developed a nonlinear mixed effect model using data from perinatally HIV-infected children who initiated ART from 1999 to 2013 in a prospective cohort study in Thailand. The main covariates of interest were: sex, ART regimen (dual nucleoside reverse-transcriptase inhibitor, non-nucleoside reverse transcriptase inhibitor (NNRTI)-, or protease inhibitor (PI)-based), baseline CD4 percentage, HIV-RNA load and CDC HIV Classification stage and occurrence of AIDS-defining events. RESULTS: A total 477 children (43% boys) contributed 18,596 height measurements over a median duration of 6.3 years on ART (interquartile range, 3.0 to 8.3). At ART initiation, median age was 6.2 years (1.8 to 9.6), 16% of children were underweight (weight-for-age z-score < - 2), 49% presented stunting (height-for-age z-score < - 2), and 7% wasting (weight-for-height z-score < - 2). The most frequent regimen at ART initiation was NNRTI-based (79%). A model with 4 components, birth length and 3 exponential functions of age accounting for the 3 growth phases was developed and show that the height-growth velocity was inversely associated with the age at ART initiation, the adult height was significantly lower in those who had experienced at least one AIDS-defining event while, as expected, the model found that adult height in females was lower than in males. Age at ART initiation, type of ART regimen, CDC stage, CD4 percentages, and HIV-RNA load were not associated with the final height. CONCLUSIONS: The younger the children at ART initiation, the greater the effect on height-growth velocity, supporting the World Health Organization's recommendation to start ART as early as possible. However, final adult height was not linked to the age at ART initiation.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Body Height/drug effects , Growth/drug effects , HIV Infections/drug therapy , Adolescent , Adult , Age Factors , Body Weight/drug effects , Chi-Square Distribution , Child , Child, Preschool , Female , Follow-Up Studies , Growth Disorders , HIV Infections/blood , HIV Infections/mortality , Humans , Infant , Lost to Follow-Up , Male , Models, Statistical , Prospective Studies , Reverse Transcriptase Inhibitors/therapeutic use , Sex Factors , Statistics, Nonparametric , Thailand , Thinness , Wasting Syndrome
16.
Article in English | MEDLINE | ID: mdl-30275094

ABSTRACT

We assessed tenofovir exposure during pregnancy and postpartum in hepatitis B virus (HBV)-infected HIV-uninfected women receiving tenofovir disoproxil fumarate (TDF) to prevent mother-to-child transmission of HBV. Data from 154 women who received TDF within a randomized controlled trial were included. Individual plasma tenofovir exposures (area under the concentration-time curve from 0 to 24 h [AUC0-24]) were estimated using a population pharmacokinetic approach. The estimated geometric mean tenofovir AUC0-24 was 20% (95% confidence interval [95% CI], 19 to 21%) lower during pregnancy than during postpartum; this modest reduction in the absence of HBV transmission suggests that no dose adjustment is needed.


Subject(s)
Antiviral Agents/pharmacokinetics , Hepatitis B virus/drug effects , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/transmission , Infectious Disease Transmission, Vertical/prevention & control , Tenofovir/pharmacokinetics , Administration, Oral , Adult , Antiviral Agents/blood , Antiviral Agents/pharmacology , Area Under Curve , Female , Hepatitis B Surface Antigens/blood , Hepatitis B virus/growth & development , Hepatitis B, Chronic/virology , Humans , Postpartum Period , Pregnancy , Tenofovir/blood , Tenofovir/pharmacology , Viral Load/drug effects
17.
J Magn Reson Imaging ; 45(1): 207-214, 2017 01.
Article in English | MEDLINE | ID: mdl-27299727

ABSTRACT

PURPOSE: To evaluate the potential for bias in functional magnetic resonance imaging (fMRI) aging studies resulting from age-related differences in magnetic field distributions that can impact echo time and functional contrast. MATERIALS AND METHODS: Magnetic field maps were taken on 31 younger adults (age: 22 ± 2.9 years) and 46 older adults (age: 66 ± 4.5 years) on a 3T scanner. Using the spatial gradients of the magnetic field map for each participant, an echo planar imaging (EPI) trajectory was simulated. The effective echo time, time at which the k-space trajectory is the closest to the center of k-space, was calculated. This was used to examine both within-subject and across-age-group differences in the effective echo time maps. The blood oxygenation level-dependent (BOLD) percent signal change resulting from those echo time shifts was also calculated to determine their impact on fMRI aging studies. RESULTS: For a single subject, the effective echo time varied as much as ±5 msec across the brain. An unpaired t-test between the effective echo time across age groups resulted in significant differences in several regions of the brain (P < 0.01). The difference in echo time was only ∼1 msec, however, which is not expected to have an important impact on BOLD fMRI percent signal change (<4%). CONCLUSION: Susceptibility-induced magnetic field gradients induce local echo-time shifts in gradient echo fMRI images, which can cause variable BOLD sensitivity across the brain. However, the age-related differences in BOLD signal are expected to be small for an fMRI study at 3T. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:207-214.


Subject(s)
Aging/physiology , Artifacts , Brain Mapping/methods , Brain/diagnostic imaging , Brain/physiology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Adult , Humans , Image Enhancement/methods , Magnetic Fields , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
18.
Psychol Res ; 81(4): 750-763, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27431389

ABSTRACT

The valence-space metaphor posits that emotion concepts map onto vertical space such that positive concepts are in upper locations and negative in lower locations. Whilst previous studies have demonstrated this pattern for positive and negative emotions e.g. 'joy' and 'sadness', the spatial location of neutral emotions, e.g. 'surprise', has not been investigated, and little is known about the effect of linguistic background. In this study, we first characterised the emotions joy, surprise and sadness via ratings of their concreteness, imageability, context availability and valence before examining the allocation of these emotions in vertical space. Participants from six linguistic groups completed either a rating task used to characterise the emotions or a word allocation task to implicitly assess where these emotions are positioned in vertical space. Our findings suggest that, across languages, gender, handedness, and ages, positive emotions are located in upper spatial locations and negative emotions in lower spatial locations. In addition, we found that the neutral emotional valence of surprise is reflected in this emotion being mapped mid-way between upper and lower locations onto the vertical plane. This novel finding indicates that the location of a concept on the vertical plane mimics the concept's degree of emotional valence.


Subject(s)
Emotions/physiology , Psycholinguistics , Verbal Behavior/physiology , Adult , Female , Humans , Male , Middle Aged , Young Adult
20.
J Med Virol ; 88(6): 1051-8, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26519647

ABSTRACT

BACKGROUND: Congenital cytomegalovirus (cCMV) infection is common among infants born to HIV-infected women. Nelfinavir (NFV), an antiretroviral drug that is safe during pregnancy, inhibits CMV replication in vitro at concentrations that standard doses achieve in plasma. We hypothesized that infants born to women receiving NFV for prevention of mother-to-child transmission of HIV (PMTCT) would have a reduced prevalence of cCMV infection. METHODS: The prevalence of cCMV infection was compared among HIV-uninfected infants whose HIV-infected mothers either received NFV for >4 weeks during pregnancy (NFV-exposed) or did not receive any NFV in pregnancy (NFV-unexposed). CMV PCR was performed on infant blood samples collected at <3 weeks from birth. RESULTS: Of the 1,255 women included, 314 received NFV for >4 weeks during pregnancy and 941 did not receive any NFV during pregnancy. The overall prevalence of cCMV infection in the infants was 2.2%, which did not differ by maternal NFV use. Maternal CD4 T cell counts were inversely correlated with risk of cCMV infection, independent of the time NFV was initiated during gestation. Infants with cCMV infection were born 0.7 weeks earlier (P = 0.010) and weighed 170 g less (P = 0.009) than uninfected infants. CONCLUSION: Among HIV-exposed uninfected infants, cCMV infection was associated with adverse perinatal outcomes. NFV use in pregnancy was not associated with protection against cCMV. Safe and effective strategies to prevent cCMV infection are needed.


Subject(s)
Cytomegalovirus Infections/congenital , HIV Infections/drug therapy , HIV Protease Inhibitors/therapeutic use , Infectious Disease Transmission, Vertical/prevention & control , Nelfinavir/therapeutic use , Pregnancy Complications, Infectious/drug therapy , Adult , CD4-Positive T-Lymphocytes/immunology , Cohort Studies , Cytomegalovirus/genetics , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/prevention & control , Cytomegalovirus Infections/virology , DNA, Viral/blood , Female , HIV Infections/transmission , HIV Infections/virology , Humans , Infant, Newborn , Mothers , Nelfinavir/adverse effects , Pregnancy , Prevalence , Risk Factors , Young Adult
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