The casts of Pompeii: Post-depositional methodological insights

The casts of Pompeii bear witness to the people who died during the Vesuvius 79 AD eruption. However, studies on the cause of death of these victims have not been conclusive. A previous important step is the understanding of the post-depositional processes and the impact of the plaster in bones, two issues that have not been previously evaluated. Here we report on the anthropological and the first chemical data obtained from the study of six casts from Porta Nola area and one from Terme Suburbane. A non-invasive chemical analysis by portable X-ray fluorescence was employed for the first time on these casts of Pompeii to determine the elemental composition of the bones and the plaster. Elemental profiles were determined providing important data that cross-referenced with anthropological and stratigraphic results, are clearly helpful in the reconstruction of the perimortem and post-mortem events concerning the history of these individuals. The comparative analyses carried out on the bone casts and other collections from burned bones of the necropolis of Porta Nola in Pompeii and Rome Sepolcreto Ostiense, and buried bones from Valencia (Spain), reveal the extent of high temperature alteration and post-depositional plaster contamination. These factors make bioarchaeological analyses difficult but still allow us to support asphyxia as the likely cause of death.

IRF5-TNOP3 polymorphisms are associated with elite control of HIV infection: A retrospective study

IRF5-TNPO3 polymorphisms have previously been related to immune response, and TNPO3 plays a role in human immunodeficiency virus (HIV)-1 infection after nuclear import. Therefore, we analyzed the genetic association between IRF5-TNPO3 polymorphisms and the HIV elite control in long-term nonprogressors (LTNPs). We performed a retrospective cohort study on 183 LTNPs, who were antiretroviral therapy-naïve with CD4⁺  ≥ 500 cells/mm³ , viral load ≤10 000 copies/mL, and asymptomatic over 10 years after HIV seroconversion. The primary outcome variable was HIV elite control (undetectable viral load in at least 90% of the measurements for at least 1 year). Seven IRF5-TNPO3 polymorphisms were genotyped using Agena Bioscience's MassARRAY platform. We found a significant association between specific IRF5-TNPO3 genotypes and HIV elite control: rs2004640 TT (aOR = 2.05; p = 0.041), rs10954213 AA (aOR = 1.95; p = 0.035), rs2280714 TT (aOR = 2.02; p = 0.031), and rs10279821 CC (aOR = 2.12; p = 0.017). We also found a significant association between IRF5-TNPO3 haplotype TATC composed of the favorable significant polymorphisms (rs2004640, rs10954213, rs2280714, and rs10279821) and the HIV elite control (aOR = 1.59; p = 0.048). IRF5-TNPO3 rs2004640, rs10954213, rs2280714, and rs10279821 polymorphisms were related to HIV elite control in LTNPs. Our data provide new knowledge about the impact of IRF5-TNPO3 polymorphisms on HIV pathogenesis to understand the phenomenon of natural HIV control.

HIV HGM biobank as a research platform for paediatric infectious diseases and COVID-19 pandemic

AIM

The initial cases of COVID-19 appeared in December 2019 and Spain was one of the most affected countries during the first wave (March to June). Since then, HIV HGM BioBank has been restructured as an established Paediatrics and Adults HIV_COVID-19 BioBank that aims at the long-term storage of samples obtained from not only HIV-1, but also from COVID-19 patients and HIV-1_COVID-19 coinfected patients.

METHODS

HIV HGM BioBank holds high quality biological samples from newborns, children, adolescents and adults with their associated clinical data. Research groups trying to establish large networks focused on research on specific clinical problems in epidemiology, biology, routes of transmission and therapies, are potential users of the clinical samples and of associated data of HIV-1_COVID-19 HGM BioBank.

RESULTS

The HIV HGM BioBank is an academic and ethical enterprise complying with all the legal regulatory rules to provide service to the society. HIV_COVID-19 HGM BioBank has been repurposed to offer an important resource for global research of COVID-19 in newborns, children, adolescents, adults and elders to study the biological effect of the pandemic.

CONCLUSION

Herein, we present a description of how HIV HGM BioBank has rapidly become an indispensable structure in modern biomedical research, including COVID-19 research.

Influence of Cold Deformation on Carbide Precipitation Kinetics in a Fe-22Mn-0.45C TWIP Steel

The carbide precipitation kinetics in a Fe-22Mn-0.45C TWIP steel subjected to three different cold-deformation levels, annealed at various temperatures, were studied. The studied carbides included chemical compositions, morphology, precipitation sites, volume fraction, and size. Manganese carbides were precipitated in a temperature range between 525 and 650 °C. Volume fraction increased with cold-deformation and decreased with annealing temperature. Carbide size increased with cold-deformation and annealing temperatures up to 625 °C, suffering a notable reduction at 650 °C. Precipitation kinetics were described by means of precipitation curves for 0.1% (vol.) of Fe-Mn-carbides. A kinetic model was used, and two stages were found. Complementarily, austenite grain size and microhardness were also measured. With increases in annealing time, microhardness decreased until it reached a nearly constant value, indicating that recrystallization was complete, while, with increases in annealing temperature, grain size increased.

High Plasma sTNF-R1 Level Is Related to Loss of Natural HIV Control in Long-Term Elite Controllers

Human immunodeficiency virus-1 (HIV-1) elite controllers are heterogeneous due to different immunovirological features. We aimed to identify plasma biomarkers associated with loss of spontaneous HIV-1 control in long-term elite controllers (HIV-LTECs). We performed a retrospective study in 60 HIV-LTECs [36 true-LTECs and 24 LTECs losing control (LTECs-LC)]. We selected a plasma sample from true-LTECs (towards the middle of the follow-up period) and two samples from LTECs-LC (one far from the loss of control and another close to loss of control). Plasma biomarkers were evaluated using multiplex immunoassays. The partial least squares-discriminant analysis provided the variable importance in projection (VIP), and the adjusted Generalized Linear Model provided the adjusted arithmetic mean ratio (aAMR). At the moment of the first LTECs-LC samples, the only plasma biomarker with a VIP≥1.5 was sTNF-R1, which showed higher values in LTECs-LC than true-LTECs [aAMR=1.62 (95%CI=1.20-2.19); p=0.001]. After a median of 3.9 (IQR=4.5) years of follow-up from the first sample, we also had access to a second plasma sample from 10 LTECs-LC patients. At the moment of this second LTECs-LC sample, the only plasma biomarker with VIP≥1.5 was also sTNF-R1, which showed higher values in LTECs-LC than true-LTECs [aAMR=1.93 (95%CI=1.41-2.65); p<0.001]. The difference between the first and second samples of LTECs-LC was significant (Δx= 6.58 (95%=0.3; 12.88); p=0.040). In conclusion, high plasma values of sTNF-R1 appear to discriminate HIV-LTECs that lose the natural control of HIV-1, helping to define a specific phenotype that may be useful for the clinical management of these patients.

Safety of G2-S16 Polyanionic Carbosilane Dendrimer as Possible HIV-1 Vaginal Microbicide

The UNAIDS objective for 2020 was 500,000 new HIV-1 infections per year; however, the latest annual reported data confirmed 1.7 million new HIV-1 infections in that year. Those data evidences the need for new prevention strategies and prophylactic treatments. This prevention crisis occurred in spite of the knowledge and availability of efficient prevention strategies. The G2-S16 is a microbicidal polyanionic carbosilane dendrimer currently being tested for topical vaginal application, which has been shown to be efficient in the prevention of HIV-1 infection. However, safety tests were lacked. For this purpose, we injected intravenously G2-S16 dendrimer to CD1 mice, thereby analyzing the hemogram, blood biochemical markers of systemic damage, accumulation in the organs and organ-tissue damage in heart, spleen, kidney, liver and brain. This work shows that even if the G2-S16 dendrimer penetrates the epithelial tissue, it does not cause vaginal irritation or tissue damage. Moreover, the i.v. injection of the G2-S16 dendrimer did not cause a damaging effect on the studied organs and it did not modify the hemogram or the biochemical plasma markers. In conclusion, the G2-S16 dendrimer has a very good safety profile, indicating that this molecule can be a very safe and efficient vaginal microbicide.

Establishment of a miRNA profile in paediatric HIV-1 patients and its potential as a biomarker for effectiveness of the combined antiretroviral therapy

miRNAs have been extensively studied in pathological conditions, including viral infections, such as those provoked by HIV-1. Several cellular and circulating miRNAs are altered during HIV-1 infection, with either beneficial effects on host defenses or enhanced virus infectivity. Blood samples were collected in sterile EDTA tubes and plasma was separated and stored, as were PBMCs. RNA was isolated and reverse-transcribed. Finally, the miRNA gene expression profile was assessed using TaqMan Array Human microRNA Card A v2.0. A comprehensive statistical analysis was performed on the results obtained. This is the first study on miRNAs in HIV-1 paediatric patients, and a miRNA profile differentiating patients starting combination antiretroviral therapy (cART) at different times after HIV-1 diagnosis was established. Thirty-four miRNAs were observed to have different expression levels between the control group and the cART group. The data indicates the need to start cART as soon as possible after the establishment of HIV-1 infection to assure the best outcome possible. Finally, the selected 34 miRNAs may be used as biomarkers for prognosis and assessing therapy effectiveness. However, more research must be conducted to establish adequate quantitative correlations.

Promising PEGylated cationic dendrimers for delivery of miRNAs as a possible therapy against HIV-1 infection

BACKGROUND

The appearance of resistance against new treatments and the fact that HIV-1 can infect various cell types and develop reservoirs and sanctuaries makes it necessary to develop new therapeutic approaches to overcome those failures.

RESULTS

Studies of cytotoxicity, genotoxicity, complexes formation, stability, resistance, release and particle size distribution confirmed that G2-SN15-PEG, G3-SN31-PEG, G2-SN15-PEG-FITC and G3-SN31-PEG-FITC dendrimers can form complexes with miRNAs being biocompatible, stable and conferring protection to these nucleic acids. Confocal microscopy and flow cytometry showed effective delivery of these four dendrimers into the target cells, confirming their applicability as delivery systems. Dendriplexes formed with the dendrimers and miRNAs significantly inhibited HIV-1 infection in PBMCs.

CONCLUSIONS

These dendrimers are efficient delivery systems for miRNAs and they specifically and significantly improved the anti-R5-HIV-1 activity of these RNA molecules.

Nanotechnology against human cytomegalovirus in vitro: polyanionic carbosilane dendrimers as antiviral agents

BACKGROUND

Human cytomegalovirus (HCMV) is a worldwide infection, causing different troublesome in immunosupressed patients and very related to Human Immunodeficiency Virus 1 (HIV-1) infection, mainly in developing countries, with a co-infection rate of 80% in Africa. The high cost of present treatments and the lack of routinely tests in these countries urge the necessity to develop new molecules or strategies against HCMV. The new treatments should be low-cost and capable of avoiding the emerging problem of resistant virus. Nanoparticles play an important role in several viral infections. Our main focus is to study the potential activity of polyanionic carbosilane dendrimers (PDC), which are hyperbranched molecules with several sulfonate or sulfate groups in their periphery, against different viruses.

RESULTS

We studied the activity of G1-S4, G2-S16 and G2-S24P PDCs in MRC-5 cell line against HCMV infection by several plaque reduction assays. Our results show that dendrimers present good biocompatibility at the concentrations tested (1-50 µM) for 6 days in cell culture. Interestingly, both G2-S16 and G2-S24P showed a remarked inhibition at 10 µM against HCMV infection. Results on attachment and virucidal assays indicated that the inhibition was not directed to the virus or the virus-cell attachment. However, results of time of addition, showed a longer lasting activity of these dendrimers in comparison to ganciclovir, and the combination of G2-S16 or G2-S24P with ganciclovir increases the HCMV inhibition around 90 %.

CONCLUSIONS

Nanotechnology, in particular polyanionic carbosilane dendrimers, have proved their potential application against HCMV, being capable of inhibiting the infection by themselves or enhancing the activity of ganciclovir, the actual treatment. These compounds represent a low-cost approach to fight HCMV infections.

Analysis of ALS-related proteins during herpes simplex virus-2 latent infection

BACKGROUND

Genetics have provided hints on potential molecular pathways involved in neurodegenerative diseases (NDD). However, the number of cases caused exclusively by genetic alterations is low, suggesting an important contribution of environmental factors to NDDs. Among these factors, viruses like herpes simplex viruses (HSV-2), capable of establishing lifelong infections within the nervous system (NS), are being proposed to have a role in NDDs. Despite promising data, there is a significant lack of knowledge on this and an urgent need for more research.

METHODS

We have set up a mouse model to study HSV latency and its associated neuroinflammation in the spinal cord. The goal of this model was to observe neuroinflammatory changes caused by HSV latent infections, and if those changes were similar to alterations observed in the spinal cord of amyotrophic lateral sclerosis (ALS) patients.

RESULTS

In infected spinal cords, we have observed a strong leukocyte infiltration and a severe alteration of microglia close to motor neurons. We have also analyzed ALS-related proteins: we have not found changes in TDP-43 and Fus in neurons, but interestingly, we have found decreased protein levels of C9orf72, of which coding gene is severely altered in some familial forms of ALS and is critical for microglia homeostasis.

CONCLUSIONS

Latent infection of HSV in the spinal cord showed altered microglia and leukocyte infiltration. These inflammatory features resembled to those observed in the spinal cord of ALS patients. No changes mimicking ALS neuropathology, such as TDP-43 cytoplasmic inclusions, were found in infected spinal cords, but a decrease in protein levels of C9orf72 was observed. Then, further studies should be required to determine whether HSV-2 has a role in ALS.

DBP rs16846876 and rs12512631 polymorphisms are associated with progression to AIDS naïve HIV-infected patients: a retrospective study

Background

Most of the circulating Vitamin D (VitD) is transported bound to vitamin D-binding protein (DBP), and several DBP single nucleotide polymorphisms (SNPs) have been related to circulating VitD concentration and disease. In this study, we evaluated the association among DBP SNPs and AIDS progression in antiretroviral treatment (ART)-naïve-HIV-infected patients.

Methods

We performed a retrospective study in 667 patients who were classified according to their pattern of AIDS progression (183 long-term non-progressors (LTNPs), 334 moderate progressors (MPs), and 150 rapid progressors (RPs)) and 113 healthy blood donors (HIV, HCV, and HBV negative subjects). We genotyped seven DBP SNPs (rs16846876, rs12512631, rs2070741, rs2282679, rs7041, rs1155563, rs2298849) using Agena Bioscience’s MassARRAY platform. The genetic association was evaluated by Generalized Linear Models adjusted by age at the moment of HIV diagnosis, gender, risk group, and VDR rs2228570 SNP. Multiple testing correction was performed by the false discovery rate (Benjamini and Hochberg procedure; q-value).

Results

All SNPs were in HWE (p > 0.05) and had similar genotypic frequencies for DBP SNPs in healthy-controls and HIV-infected patients. In unadjusted GLMs, we only found significant association with AIDS progression in rs16846876 and rs12512631 SNPs. In adjusted GLMs, DBP rs16846876 SNP showed significant association under the recessive inheritance model [LTNPs vs. RPs (adjusted odds ratio (aOR) = 3.53; q-value = 0.044) and LTNPs vs. MPs (aOR = 3.28; q-value = 0.030)] and codominant [LTNPs vs. RPs (aOR = 4.92; q-value = 0.030) and LTNPs vs. MPs (aOR = 3.15; q-value = 0.030)]. Also, we found DBP rs12512631 SNP showed significant association in the inheritance model dominant [LTNPs vs. RPs (aOR = 0.49; q-value = 0.031) and LTNPs vs. MPs (aOR = 0.6; q-value = 0.047)], additive [LTNPs vs. RPs (aOR = 0.61; q-value = 0.031)], overdominant [LTNPs vs. MPs (aOR = 0.55; q-value = 0.032)], and codominant [LTNPs vs. RPs (aOR = 0.52; q-value = 0.036) and LTNPs vs. MPs (aOR = 0.55; q-value = 0.032)]. Additionally, we found a significant association between DBP haplotypes (composed by rs16846876 and rs12512631) and AIDS progression (LTNPs vs RPs): DBP haplotype AC (aOR = 0.63; q-value = 0.028) and the DBP haplotype TT (aOR = 1.64; q-value = 0.028).

Conclusions

DBP rs16846876 and rs12512631 SNPs are related to the patterns of clinical AIDS progression (LTNP, MP, and RP) in ART-naïve HIV-infected patients. Our findings provide new knowledge about AIDS progression that may be relevant to understanding the pathogenesis of HIV infection.

Dendronized magnetic nanoparticles for HIV-1 capture and rapid diagnostic

Human immunodeficiency virus type 1 (HIV-1) remains a global public health problem. Detection and reduction of the rates of late diagnosis of HIV-1 infection are one of the main challenges in combating the HIV-1 epidemic. Magnetic nanoparticles (MNPs) have several characteristics that make them susceptible to capture HIV-1 of a wide range of biological samples reducing waiting times between the acquisition of HIV-1 infection and its detection by current techniques. Carbosilane dendrons decorated with peripheral carboxyl groups and alcoxysilane function at the focal point have been used to stabilize MNPs by co-precipitation method in one step. The characterization of these systems and of their carboxylate analogues was performed by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), ζ potential and thermal gravimetric analysis (TGA). The ability of carboxyl and carboxylate MNPs to capture R5-HIV-1 and X4-HIV-1 strains was evaluated to achieve a rapid and easy diagnostic method in order to reduce or eliminate the risk of HIV-1 transmission.

In silico search, chemical characterization and immunogenic evaluation of amino-terminated G4-PAMAM-HIV peptide complexes using three-dimensional models of the HIV-1 gp120 protein

Peptide epitopes have been widely used to develop synthetic vaccines and immunotherapies. However, peptide epitopes may exhibit poor absorption or immunogenicity due to their low molecular weights. Conversely, fourth-generation polyamidoamine (G4-PAMAM) dendrimers are nonimmunogenic and relatively nontoxic synthetic nanoparticles that have been used as adjuvants and nanocarriers of small peptides and to improve nasal absorption. Based on this information, we hypothesized that the combination of intranasal immunization and G4-PAMAM dendrimers would be useful for enhancing the antibody responses of HIV-1 gp120 peptide epitopes. Therefore, we first used structural data, peptide epitope predictors and docking and MD simulations on MHC-II to identify two peptide epitopes on the CD4 binding site of HIV-1 gp120. The formation of G4-PAMAM-peptide complexes was evaluated in silico (molecular docking studies using different G4-PAMAM conformations retrieved from MD simulations as well as the MMGBSA approach) and validated experimentally (electrophoresis, ¹H NMR and cryo-TEM). Next, the G4-PAMAM dendrimer-peptide complexes were administered intranasally to groups of female BALB/cJ mice. The results showed that both peptides were immunogenic at the systemic and mucosal levels (nasal and vaginal), and G4-PAMAM dendrimer-peptide complexes improved IgG and IgA responses in serum and nasal washes. Thus, G4-PAMAM dendrimers have potential for use as adjuvants and nanocarriers of peptides.

VDR rs2228570 Polymorphism Is Related to Non-Progression to AIDS in Antiretroviral Therapy Naïve HIV-Infected Patients

Background: Vitamin D is a fundamental regulator of host defenses by activating genes related to innate and adaptive immunity. In this study, we analyzed the association among single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene, with clinical patterns of AIDS progression in antiretroviral treatment (ART)-naïve HIV-infected patients. Methods: We conducted a retrospective study in 667 HIV-infected patients, who were classified within three groups according to their AIDS progression pattern (183 long-term non-progressors (LTNPs), 334 moderate progressors (MPs), and 150 rapid progressors (RPs)). Five VDR SNPs (rs11568820, rs4516035, rs2228570, rs1544410, and rs7975232) were genotyped using Agena Bioscience’s MassARRAY platform. Results: Significant association results were found for rs2228570. Within all HIV patients, the presence of T allele at VDR rs2228570 SNP was protective against AIDS progression (ordinal outcome) under additive (adjusted odds ratio (aOR) = 0.75; p = 0.009), dominant (aOR = 0.69; p = 0.015), and codominant (aOR = 0.56; p = 0.017) inheritance models. In addition, the same allele was protective under additive and codominant inheritance models when we compared with LTNPs vs. RPs [aOR = 0.64 (p = 0.019) and aOR = 0.37 (p = 0.018), respectively] and when we compared MPs vs. RPs [aOR = 0.72 (p = 0.035) and aOR = 0.45 (p = 0.028), respectively]. Conclusions: The VDR rs2228570 T allele was related to a lower AIDS progression pattern in ART-naïve HIV-infected patients. These findings expand upon the knowledge about HIV pathogenesis in untreated HIV-infected patients with different clinical outcomes.

High Plasma Levels of sTNF-R1 and CCL11 Are Related to CD4+ T-Cells Fall in Human Immunodeficiency Virus Elite Controllers With a Sustained Virologic Control

Our aim was to analyze the relationship between plasma inflammatory biomarkers and CD4+ T-cells evolution in human immunodeficiency virus (HIV) elite controllers (HIV-ECs) with a suppressed viremia. We carried out a retrospective study in 30 HIV-ECs classified into two groups: those showing no significant loss of CD4+ T-cells during the observation period (stable CD4+, n = 19) and those showing a significant decrease of CD4+ T-cells (decline CD4+, n = 11). Baseline plasma biomarkers were measured using a multiplex immunoassay: sTNF-R1, TRAIL, sFas (APO), sFasL, TNF-α, TNF-β, IL-8, IL-18, IL-6, IL-10, IP-10, MCP-1, MIP-1α, MIP-1β, RANTES, SDF1α, GRO-α, and CCL11. Baseline levels of sTNF-R1 and CCL11 and sTNF-R1/TNF-α ratio correlated with the slope of CD4+ T-cells (cells/μl/year) during follow-up [r = -0.370 (p = 0.043), r = -0.314 (p = 0.091), and r = -0.381 (p = 0.038); respectively]. HIV-ECs with declining CD4+ T-cells had higher baseline plasma levels of sTNF-R1 [1,500.7 (555.7; 2,060.7) pg/ml vs. 450.8 (227.9; 1,263.9) pg/ml; p = 0.018] and CCL11 [29.8 (23.5; 54.9) vs. 19.2 (17.8; 29.9) pg/ml; p = 0.041], and sTNF-R1/TNF-α ratio [84.7 (33.2; 124.2) vs. 25.9 (16.3; 75.1); p = 0.012] than HIV-1 ECs with stable CD4+ T-cells. The area under the receiver operating characteristic (ROC) curve [area under ROC curve (AUROC)] were 0.758 ± 0.093 (sTNF-R1), 0.727 ± 0.096 (CCL11), and 0.777 ± 0.087 (sTNF-R1/TNF-α). The cut-off of 75th percentile (high values) for these biomarkers had 71.4% positive predictive value and 73.9% negative predictive value for anticipating the evolution of CD4+ T-cells. In conclusion, the loss of CD4+ T-cells in HIV-ECs was associated with higher levels of two plasma inflammatory biomarkers (sTNF-R1 and CCL11), which were also reasonably accurate for the prediction of the CD4+ T-cells loss.

Computational Screening of New Orthogonal Metal-Free Dipolar Cycloadditions of Mesomeric Betaines

Computational strategies have gained increasing impact in the de novo design of large molecular sets targeted to a desired application. Herein, DFT-assisted theoretical analyses of cycloadditions, involving mesoionic dipoles and strained cycloalkynes, unveil a series of unexplored mesomeric betaines as vastly superior candidates for orthogonal applications. Thus, isosydnones; thiosydnones; and a six-membered homolog, 6-oxo-1,3-oxazinium-4-olate, exhibit enhanced reactivity with respect to sydnone, which is the archetypal mesoionic ring employed so far in orthogonal chemistry. These compounds were found by assessing energy barriers and transition structures, which are largely governed by electron fluxes from dipolarophile to dipole and noncovalent interactions. Charge-transfer analysis also accounts for previous experimental and theoretical results gathered in the literature, and provides a rationale for further substitution variations. The above naked dipoles release only CO₂ as a byproduct through retro-Diels-Alder of the resulting cycloadducts. These results should invite practitioners to look at such underestimated dipoles and could also help to minimize the number of experiments.

Increased CD127+ and decreased CD57+ T cell expression levels in HIV-infected patients on NRTI-sparing regimens

BACKGROUND

NRTIs-sparing regimens exert favourable profiles on T-cell homeostasis associated parameters. Our aim was to analyze the effect of NRTIs sparing regimen (NRTI-sparing-cART) vs NRTIs-containing regimen (NRTI-cART), on T-cell homeostasis associated parameters in naive HIV-infected patients.

METHODS

Biomarkers of cell survival (CD127) and replicative senescence (CD57), were measured by multiparametric flow cytometry for T-cell phenotyping on peripheral blood mononuclear cells (PBMCs) samples just before (baseline) and after 48 weeks of undetectable viral load in patients on NRTI-sparing-cART (N = 13) and NRTI-cART (N = 14). After 48 weeks a subgroup of patients (n = 5) on NRTI-cART switched to NRTI-sparing-cART for another additional 48 weeks. In vitro assays were performed on PBMCs from HIV-uninfected healthy donors exposed or not to HIV. To analyze the independent factors associated with type of cART bivariate and stepwise multivariate analysis were performed after adjusting for basal CD4+, CD8+ and nadir CD4+ T-cell counts.

RESULTS

After 48 weeks of a NRTI-sparing-cART vs NRTI-cART patients have higher effector memory (EM) CD4+ CD127+ T-cell levels, lower EM CD4+ CD57+ T-cell levels, higher CD8+ CD127+ T-cell levels, lower CD8+ CD57+ T-cell levels and higher memory CD8+ T-cell levels. This effect was confirmed in the subgroup of patients who switched to NRTI-sparing-cART. In vitro assays confirmed that the deleterious effect of a NRTIs-containing regimen was due to NRTIs.

CONCLUSIONS

The implementation of NRTI-sparing regimens, with a favourable profile in CD127 and CD57 T-cell expression, could benefit cART-patients. These results could have potential implications in a decrease in the number of Non-AIDS events.

Carbosilane dendrons with fatty acids at the core as a new potential microbicide against HSV-2/HIV-1 co-infection

Herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1) represent the two most frequent sexually transmitted infections (STI) worldwide. Epidemiological studies suggest that HSV-2 increases the risk of HIV-1 acquisition approximately 3-fold mainly due to the clinical and immunological manifestations. In the absence of vaccines against both STI, the development of new preventive strategies has become essential for further studies. We performed the screening of six novel polyanionic carbosilane dendrons to elucidate their potential activity against HSV-2/HIV-1 co-infection and their mechanism of action. These new nanoparticles are carbosilane branched dendrons from first to third generation, with palmitic or hexanoic fatty acids as the core and capped with sulfonate groups, named G1_d-STE2Hx, G2_d-STE4Hx, G3_d-STE8Hx, G1_d-STE2Pm, G2_d-STE4Pm and G3_d-STE8Pm. G3_d-STE8Hx and G3_d-STE8Pm carbosilane branched dendrons showed high viability. These dendrons also showed a great broad-spectrum antiviral activity, as well as a suitable efficacy against HIV-1 even if the mucosal disruption occurs as a consequence of HSV-2 infection. Our results exert high inhibition against HSV-2 and HIV-1 by blocking the entry of both viruses with the median effective concentration EC₅₀ values in the nanomolar range. Additionally, G3_d-STE8Hx and G3_d-STE8Pm retained their anti-HSV-2/HIV-1 activity at different pH values. G3_d-STE8Hx and G3_d-STE8Pm dendrons may be potential candidates as dual-acting microbicides against HSV-2/HIV-1 co-infection.

Safety and vaccine-induced HIV-1 immune responses in healthy volunteers following a late MVA-B boost 4 years after the last immunization

Background

We have previously shown that an HIV vaccine regimen including three doses of HIV-modified vaccinia virus Ankara vector expressing HIV-1 antigens from clade B (MVA-B) was safe and elicited moderate and durable (1 year) T-cell and antibody responses in 75% and 95% of HIV-negative volunteers (n = 24), respectively (RISVAC02 study). Here, we describe the long-term durability of vaccine-induced responses and the safety and immunogenicity of an additional MVA-B boost.

Methods

13 volunteers from the RISVAC02 trial were recruited to receive a fourth dose of MVA-B 4 years after the last immunization. End-points were safety, cellular and humoral immune responses to HIV-1 and vector antigens assessed by ELISPOT, intracellular cytokine staining (ICS) and ELISA performed before and 2, 4 and 12 weeks after receiving the boost.

Results

Volunteers reported 64 adverse events (AEs), although none was a vaccine-related serious AE. After 4 years from the 1^st dose of the vaccine, only 2 volunteers maintained low HIV-specific T-cell responses. After the late MVA-B boost, a modest increase in IFN-γ T-cell responses, mainly directed against Env, was detected by ELISPOT in 5/13 (38%) volunteers. ICS confirmed similar results with 45% of volunteers showing that CD4+ T-cell responses were mainly directed against Env, whereas CD8+ T cell-responses were similarly distributed against Env, Gag and GPN. In terms of antibody responses, 23.1% of the vaccinees had detectable Env-specific binding antibodies 4 years after the last MVA-B immunization with a mean titer of 96.5. The late MVA-B boost significantly improved both the response rate (92.3%) and the magnitude of the systemic binding antibodies to gp120 (mean titer of 11460). HIV-1 neutralizing antibodies were also enhanced and detected in 77% of volunteers. Moreover, MVA vector-specific T cell and antibody responses were boosted in 80% and 100% of volunteers respectively.

Conclusions

One boost of MVA-B four years after receiving 3 doses of the same vaccine was safe, induced moderate increases in HIV-specific T cell responses in 38% of volunteers but significantly boosted the binding and neutralizing antibody responses to HIV-1 and to the MVA vector.

Trial registration

ClinicalTrials.gov NCT01923610.

IL7RA polymorphisms are not associated with AIDS progression

BACKGROUND

Our aim was to determine whether α-chain of the IL-7 receptor (IL7RA) polymorphisms (rs10491434, rs6897932 and rs987106) are associated with the clinical pattern of AIDS progression in ART-naïve HIV-infected patients.

MATERIALS AND METHODS

We carried out a cross-sectional study in 673 HIV-infected patients who were classified into three groups according to the clinical pattern of AIDS progression (188 long-term nonprogressors (LTNPs), 334 moderate progressors (MPs) and 151 rapid progressors (RPs)). Additionally, 134 healthy blood donors participated as a Control-group. We selected three IL7RA polymorphisms located at three regulatory regions [rs6897932 (exon 6), rs987106 (intronic region) and rs10491434 (3'UTR)]. DNA genotyping was performed using Sequenom's MassARRAY platform.

RESULTS

The Control-group and all HIV-infected patients had similar age and percentage of males. LTNP-group was older at HIV diagnosis and at the inclusion in the study and had higher percentage of intravenous drug users (IDU) (P < 0·001). Besides, LTNP-group had lower proportion of male patients and homosexual HIV transmission than MP and RP groups (P < 0·001). Moreover, similar values of allelic, genotypic and haplotype frequencies for IL7RA polymorphisms were found between healthy controls and HIV-infected patients (P > 0·05), and among different subgroups of HIV patients according to AIDS progression (LTNPs, MPs and RPs) (P > 0·05). The adjusted logistic regression did not show any significant association between IL7RA polymorphisms and AIDS progression.

CONCLUSIONS

IL7RA polymorphisms (rs6897932, rs987106 and rs10491434) were not associated with AIDS progression in Spanish population. Therefore, IL7RA polymorphisms do not seem to help us to understand HIV pathogenesis in untreated HIV-infected patients with different clinical evolution.

CCR5+ CD8 T-cell levels and monocyte activation precede the onset of acute coronary syndrome in HIV-infected patients on antiretroviral therapy

Acute coronary syndrome (ACS) is nowadays one of the leading causes of morbid-mortality in HIV-infected population, but innate and adaptive immune mechanisms preceding this event are unknown. In this work we comprehensively and longitudinally observed, by multiparametric flow cytometry and following a case-control design, increased CCR5⁺CD8⁺ T-cells levels and monocytes expressing activation and adhesion markers in HIV-infected patients who are going to suffer ACS. In addition, we found direct associations between activated CD8⁺ T-cells and myeloid cells that were only statistically significant in the group of patients with ACS and in the follow up time point just before the ACS. Our data highlight the important role of CCR5 in the onset of ACS and suggest this receptor as a marker of cardiovascular risk and potential therapeutic target to prevent the development of such non-AIDS-related event in HIV-infected patients.

Polyanionic carbosilane dendrimers prevent hepatitis C virus infection in cell culture

Hepatitis C virus (HCV) infection is a major biomedical problem worldwide. Although new direct antiviral agents (DAAs) have been developed for the treatment of chronic HCV infection, the potential emergence of resistant virus variants and the difficulties to implement their administration worldwide make the development of novel antiviral agents an urgent need. Moreover, no effective vaccine is available against HCV and transmission of the virus still occurs particularly when prophylactic measures are not taken. We used a cell-based system to screen a battery of polyanionic carbosilane dendrimers (PCDs) to identify compounds with antiviral activity against HCV and show that they inhibit effective virus adsorption of major HCV genotypes. Interestingly, one of the PCDs irreversibly destabilized infectious virions. This compound displays additive effect in combination with a clinically relevant DAA, sofosbuvir. Our results support further characterization of these molecules as nanotools for the control of hepatitis C virus spread.

Mechanistic Studies of Viral Entry: An Overview of Dendrimer-Based Microbicides As Entry Inhibitors Against Both HIV and HSV-2 Overlapped Infections

This review provides an overview of the development of different dendrimers, mainly polyanionic, against human immunodeficiency virus (HIV) and genital herpes (HSV-2) as topical microbicides targeting the viral entry process. Vaginal topical microbicides to prevent sexually transmitted infections such as HIV and HSV-2 are urgently needed. To inhibit HIV/HSV-2 entry processes, new preventive targets have been established to maximize the current therapies against wild-type and drug-resistant viruses. The entry of HIV/HSV-2 into target cells is a multistep process that triggers a cascade of molecular interactions between viral envelope proteins and cell surface receptors. Polyanionic dendrimers are highly branched nanocompounds with potent activity against HIV/HSV-2. Inhibitors of each entry step have been identified with regard to generations and surface groups, and possible roles for these agents in anti-HIV/HSV-2 therapies have also been discussed. Four potential binding sites for impeding HIV infection (HSPG, DC-SIGN, GSL, and CD4/gp120 inhibitors) and HSV-2 infection (HS, gB, gD, and gH/gL inhibitors) exist according to their mechanisms of action and structures. This review clarifies that inhibition of HIV/HSV-2 entry continues to be a promising target for drug development because nanotechnology can transform the field of HIV/HSV-2 prevention by improving the efficacy of the currently available antiviral treatments.

Prebiotic-Like Condensations of Cyanamide and Glyoxal: Revisiting Intractable Biotars

We report a detailed investigation into the nature of products that are generated by the reactions of cyanamide and glyoxal, two small molecules of astrochemical and prebiotic significance, under different experimental conditions. The experimental data suggest that the formation of oligomeric structures is related in part to the formation of insoluble tholins in the presence of oxygen-containing molecules. Although oligomerization proceeds well in water, product isolation turned out to be impractical. Instead, solid precipitates were obtained easily in acetone. Crude mixtures have been thoroughly scrutinized by spectroscopic methods, in particular NMR and mass spectroscopy (ESI mode), which are all consistent with the generation of a few functional groups that are embedded into regular chains of five- and six-membered rings, thereby pointing to a supramolecular organization. Three different models of cross-condensation and chain growth are suggested. These synthetic explorations provide further insights into the formation of complex organic matter in interstellar scenarios and extraterrestrial bodies that might have played a pivotal role in chemical evolution.

On the Plausibility of Pseudosugar Formation in Cometary Ices and Oxygen-rich Tholins

We revisit herein the formation and structure of dihydroxy dioxanes, which can be obtained from prebiotically available precursors and can be regarded as primeval sugar surrogates. Previous studies dealing with the heterogeneous composition of interstellar bodies point to the existence of significant amounts of small polyalcohols along with oxygen-containing oligomers. Even though such derivatives did not give rise to nucleosides and oligonucleotides, nor they were incorporated into subsequent metabolic routes, molecular chimeras based on sugar-like species could be opportunistic scaffolds in pre-evolutionary scenarios. We could figure out that pseudosugars, assembled by hemiacetalic bonds from available precursors in both interstellar and terrestrial scenarios, were presumably more abundant than thought. Moreover, these species share some key features with naturally-occurring sugar rings, such as anomeric preferences, coordinating ability, and the prevalent occurrence of racemic compounds.

A Phase I Randomized Therapeutic MVA-B Vaccination Improves the Magnitude and Quality of the T Cell Immune Responses in HIV-1-Infected Subjects on HAART

Trial Design

Previous studies suggested that poxvirus-based vaccines might be instrumental in the therapeutic HIV field. A phase I clinical trial was conducted in HIV-1-infected patients on highly active antiretroviral therapy (HAART), with CD4 T cell counts above 450 cells/mm³ and undetectable viremia. Thirty participants were randomized (2:1) to receive either 3 intramuscular injections of MVA-B vaccine (coding for clade B HIV-1 Env, Gag, Pol and Nef antigens) or placebo, followed by interruption of HAART.

Methods

The magnitude, breadth, quality and phenotype of the HIV-1-specific T cell response were assayed by intracellular cytokine staining (ICS) in 22 volunteers pre- and post-vaccination.

Results

MVA-B vaccine induced newly detected HIV-1-specific CD4 T cell responses and expanded pre-existing responses (mostly against Gag, Pol and Nef antigens) that were high in magnitude, broadly directed and showed an enhanced polyfunctionality with a T effector memory (TEM) phenotype, while maintaining the magnitude and quality of the pre-existing HIV-1-specific CD8 T cell responses. In addition, vaccination also triggered preferential CD8⁺ T cell polyfunctional responses to the MVA vector antigens that increase in magnitude after two and three booster doses.

Conclusion

MVA-B vaccination represents a feasible strategy to improve T cell responses in individuals with pre-existing HIV-1-specific immunity.

Trial Registration

ClinicalTrials.gov NCT01571466

Triple combination of carbosilane dendrimers, tenofovir and maraviroc as potential microbicide to prevent HIV-1 sexual transmission

AIM

To research the synergistic activity by triple combinations of carbosilane dendrimers with tenofovir and maraviroc as topical microbicide.

METHODS

Cytotoxicity, anti-HIV-1 activity, vaginal irritation and histological analysis of triple combinations were determined. Analysis of combined effects and the median effective concentration were performed using CalcuSyn software.

RESULTS

Combinations showed a greater broad-spectrum anti-HIV-1 activity than the single-drug, and preserved this activity in acid environment or seminal fluid. The strongest combinations were G2-STE16/G2-S24P/tenofovir, G2-STE16/G2-S16/maraviroc and G2-STE16/tenofovir/maraviroc at 2:2:1, 10:10:1 10:5:1 ratios, respectively. They demonstrated strong synergistic activity profile due to the weighted average combination indices varied between 0.06 and 0.38. No irritation was detected in female BALB/c mice.

CONCLUSION

The three-drug combination increases their antiviral potency and act synergistically as potential microbicide.

Prevention vaginally of HIV-1 transmission in humanized BLT mice and mode of antiviral action of polyanionic carbosilane dendrimer G2-S16

The development of a safe, effective, and low-priced topical microbicide to prevent HIV-1 sexual transmission is urgently needed. The emerging field of nanotechnology plays an important role in addressing this challenge. We demonstrate that topical vaginal administration of 3% G2-S16 prevents HIV-1JR-CSF transmission in humanized (h)-BLT mice in 84% with no presence of HIV-1 RNA and vaginal lesions. Second-generation polyanionic carbosilane dendrimer G2-S16 with silica core and 16 sulfonate end-groups exerts anti-HIV-1 activity at an early stage of viral replication, blocking the gp120/CD4 interaction, acting on the virus, and inhibiting the cell-to-cell HIV-1 transmission, confirming its multifactorial and non-specific ability. This study represents the first demonstration that transmission of HIV-1 can be efficiently blocked by vaginally applied G2-S16 in h-BLT mice. These findings provide a step forward in the development of G2-S16-based vaginal microbicides to prevent vaginal HIV-1 transmission in humans.

FROM THE CLINICAL EDITOR

HIV infections remain a significant problem worldwide and the major route of transmission is through sexual activity. In this article, the authors developed an antiviral agent containing polyanionic carbosilane dendrimer with silica core and 16 sulfonate end-groups. When applied vaginally, this was shown to exert anti-HIV protection. These positive findings may offer hope in the fight against the spread of HIV epidemic.

Safety and immunogenicity of a modified vaccinia Ankara-based HIV-1 vaccine (MVA-B) in HIV-1-infected patients alone or in combination with a drug to reactivate latent HIV-1

OBJECTIVES

The safety, immunogenicity, impact on the latent reservoir and rebound of viral load after therapeutic HIV-1 vaccination with recombinant modified vaccinia Ankara-based (MVA-B) HIV-1 vaccine expressing monomeric gp120 and the fused Gag-Pol-Nef polyprotein of clade B with or without a drug to reactivate latent HIV-1 (disulfiram) were assessed.

METHODS

HIV-1-infected patients were randomized to receive three injections of MVA-B (n = 20) or placebo (n = 10). Twelve patients (eight who received vaccine and four who were given placebo) received a fourth dose of MVA-B followed by 3 months of disulfiram. Combined ART (cART) was discontinued 8 weeks after the last dose of MVA-B. Clinical Trials.gov identifier: NCT01571466.

RESULTS

MVA-B was safe and well tolerated. A minor, but significant, increase in the T cell responses targeting vaccine inserts of Gag was observed [a median of 290, 403 and 435 spot-forming-cells/10(6) PBMCs at baseline, after two vaccinations and after three vaccinations, respectively; P = 0.02 and P = 0.04]. After interruption of cART, a modest delay in the rebound of the plasma viral load in participants receiving vaccine but not disulfiram was observed compared with placebo recipients (P = 0.01). The dynamics of the viral load rebound did not change in patients receiving MVA-B/disulfiram. No changes in the proviral reservoir were observed after disulfiram treatment.

CONCLUSIONS

MVA-B vaccination was a safe strategy to increase Gag-specific T cell responses in chronically HIV-1-infected individuals, but it did not have a major impact on the latent reservoir or the rebound of plasma viral load after interruption of cART when given alone or in combination with disulfiram.

Carbosilane dendrimers as gene delivery agents for the treatment of HIV infection

Despite the use of siRNA in the downregulation of HIV-1 replication which has been reported, CD4 T lymphocytes are difficult to transfect with non-viral vectors. We determined whether second generation carbosilane dendrimers (2G-NN16 and 2G-03NN24) may be efficient transfectants in CD4 T lymphocytes. Dendrimers were also tested on macrophages to determine whether they can modify macrophage phenotype and induce an inflammatory response. The nanoconjugate formed by 2G-03NN24/siRNA-Nef presents the highest inhibition of HIV-1 replication. Dendrimers presented safety properties because they did not induce proliferation on CD4 T lymphocytes and decrease the release of TNFα and IL-12p40 by macrophages. Both dendrimers also decrease the phagocytosis activity. Additionally, 2G-03NN24 dendrimer decreases the CCL2 and CCR2 expression in macrophages. Carbosilane dendrimers 2G-NN16 and 2G-03NN24 can be used as efficient non-viral vectors for gene therapy applications, mainly in the treatment of HIV infection.

Synergistic activity profile of carbosilane dendrimer G2-STE16 in combination with other dendrimers and antiretrovirals as topical anti-HIV-1 microbicide

Polyanionic carbosilane dendrimers represent opportunities to develop new anti-HIV microbicides. Dendrimers and antiretrovirals (ARVs) acting at different stages of HIV replication have been proposed as compounds to decrease new HIV infections. Thus, we determined the potential use of our G2-STE16 carbosilane dendrimer in combination with other carbosilane dendrimers and ARVs for the use as topical microbicide against HIV-1. We showed that these combinations obtained 100% inhibition and displayed a synergistic profile against different HIV-1 isolates in our model of TZM.bl cells. Our results also showed their potent activity in the presence of an acidic vaginal or seminal fluid environment and did not activate an inflammatory response. This study is the first step toward exploring the use of different anionic carbosilane dendrimers in combination and toward making a safe microbicide. Therefore, our results support further studies on dendrimer/dendrimer or dendrimer/ARV combinations as topical anti-HIV-1 microbicide.

FROM THE CLINICAL EDITOR

This paper describes the first steps toward the use of anionic carbosilane dendrimers in combination with antivirals to address HIV-1, paving the way to further studies on dendrimer/dendrimer or dendrimer/ARV combinations as topical anti-HIV-1 microbicides.

Synthesis, structure and molecular modelling of anionic carbosilane dendrimers

Anionic carbosilane dendrimers of generations 1-3 have been synthesized containing carboxylate G(n)X(C(2)H(4)CO(2)Na)(m) and sulfonate G(n)X(C(2)H(4)SO(3)Na)(m) peripheral groups and derived from two different cores, 1,3,5-(HO)(3)C(6)H(3) (X = O(3)) and Si(C(3)H(5))(4) (X = Si). The peripheral anionic groups make these dendrimers water soluble, despite their highly hydrophobic framework. These dendrimers present a net negative charge in water, which was influenced by the pH of the medium. This characteristic was studied by pH titration. Also molecular modeling calculations have been performed to study differences in an aqueous medium between carboxylate and sulfonate dendrimers of different cores. The results obtained were also compared with those obtained from DOSY NMR experiments and zeta-potential measurements.

GCN2 has inhibitory effect on human immunodeficiency virus-1 protein synthesis and is cleaved upon viral infection

The reversible phosphorylation of the alpha-subunit of eukaryotic translation initiation factor 2 (eIF2alpha) is a well-characterized mechanism of translational control in response to a wide variety of cellular stresses, including viral infection. Beside PKR, the eIF2alpha kinase GCN2 participates in the cellular response against viral infection by RNA viruses with central nervous system tropism. PKR has also been involved in the antiviral response against HIV-1, although this antiviral effect is very limited due to the distinct mechanisms evolved by the virus to counteract PKR action. Here we report that infection of human cells with HIV-1 conveys the proteolytic cleavage of GCN2 and that purified HIV-1 and HIV-2 proteases produce direct proteolysis of GCN2 in vitro, abrogating the activation of GCN2 by HIV-1 RNA. Transfection of distinct cell lines with a plasmid encoding an HIV-1 cDNA clone competent for a single round of replication resulted in the activation of GCN2 and the subsequent eIF2alpha phosphorylation. Moreover, transfection of GCN2 knockout cells or cells with low levels of phosphorylated eIF2alpha with the same HIV-1 cDNA clone resulted in a marked increase of HIV-1 protein synthesis. Also, the over-expression of GCN2 in cells led to a diminished viral protein synthesis. These findings suggest that viral RNA produced during HIV-1 infection activates GCN2 leading to inhibition of viral RNA translation, and that HIV-1 protease cleaves GCN2 to overcome its antiviral effect.

Vector replication and expression of HIV-1 antigens by the HIV/AIDS vaccine candidate MVA-B is not affected by HIV-1 protease inhibitors

MVA-B is an attenuated poxvirus vector expressing human immunodeficiency virus type 1 Env, Gag, Pol, and Nef antigens from clade B, and is considered a promising HIV/AIDS vaccine candidate. Recently, a phase I clinical trial in human healthy volunteers has shown that MVA-B is safe and highly immunogenic, inducing broad, polyfunctional, and long-lasting CD4(+) and CD8(+) T cell responses to HIV-1 antigens, with preference for effector memory T cells; and it also triggers the induction of specific antibodies to Env in most of the vaccines. While MVA recombinants expressing HIV-1 antigens are being used or plan to use in therapeutic clinical trials, little is known on the effect of HIV-1 highly active antiretroviral therapy in MVA life cycle. To define this role, here we have evaluated in established cell cultures and human dendritic cells to what extent different HIV-1 protease inhibitors affect virus replication and expression of HIV-1 antigens during MVA-B infection. The results obtained revealed that the most commonly used HIV-1 protease inhibitors (atazanavir, ritonavir, and lopinavir) had no effect on MVA-B virus growth kinetics, even at higher concentrations than those normally used on HAART. Furthermore, expression of gp120 and the fused Gag-Pol-Nef polyprotein in permissive and non-permissive cells infected with MVA-B were also not affected. These findings are relevant information for the therapeutic use of MVA-B as an HIV-1/AIDS vaccine.

Acute toxicity of alkylpolyglucosides to Vibrio fischeri, Daphnia magna and microalgae: a comparative study

In this paper, toxicity values of alkylpolyglucosides have been determined by applying the 24-h immobilization test with Daphnia magna, the LumiStox(®) 300 test which employs the luminescent bacteria Photobacterium phosphoreum and the test with Selenastrum capricornutum. Three alkylpolyglucosides with different alkyl chain and degree of polymerisation have been tested. For all tests, the results indicated that Vibrio fischeri was more sensitive to toxic effects from alkylpolyglucosides than was D. magna or S. capricornutum. The results demonstrate considerable variation in toxicity responses within structurally related glucose-based surfactants regardless of the species tested. The toxicity increased as the critical micelle concentration decreased, and as the alkyl chain length and resultant hydrophobicity increased.

Effect of concentration on the primary and ultimate biodegradation of alkylpolyglucosides in aerobic biodegradation tests

This study examines the primary and ultimate biodegradation of a non-ionic surfactant, an alkylpolyglucoside, in ready biodegradability tests. The surfactant concentration was tested by the anthrone method, while the ultimate biodegradation (mineralization) was analyzed by the total organic carbon determinations. The influence of the concentration on the extent of primary and ultimate biodegradation and the kinetics of degradation also were determined. The primary and ultimate biodegradation was studied at different initial concentrations-15, 25, 50, 75, and 100 mg/L. The increasing concentration of test chemical from 15 to 100 mg/L resulted in a decrease in the relative maximum mineralization rate and longer estimated lag times by a factor of approximately 4.3. During the degradative process, two different stages were noted; these are better described with Quiroga and first-order kinetic models, respectively. For the study of the influence of concentration, the parameters characteristic of the biodegradation profiles in the different biodegradation assays were evaluated.

A new model for mapping the peptide backbone: predicting proton chemical shifts in proteins

This paper describes a methodology that correlates experimental chemical shifts (at the alpha proton) of proteins with their geometrical data (both dihedral angles and distances) obtained from 13 representative proteins, which are taken from the Protein Data Bank (PDB) and the BioMagRes Data Bank (BMRB). To this end, the experimentally measured proton chemical shifts of simple amides have been correlated with DFT-based calculated structures, at the B3PW91/6-31G* level. This results in a series of mathematical relationships, which are extrapolated to the above-mentioned proteins giving rise to a modified equation for such skeleta. It is relevant to note that the equation is also supported by a clear comparison with NMR data of a protein beyond the chosen set, such as insulin, even with lower errors. The model also relates the dependence of chemical shifts on hydrophobic and anisotropic effects at the amino acid residues.

Pediatric HIV BioBank: a new role of the Spanish HIV BioBank in pediatric HIV research

The vulnerability of children has long raised ethical concerns resulting in the lack of inclusion of children in research studies. This has impeded the development of relevant medical therapies specific for children. In response to these circumstances, international policies have begun to recognize the need to carry out research focused on children. Translational HIV infection research is highly dependent on many factors including the availability, quality, and traceability of samples and their associated data under a strict system of quality management. The primary objective of the Pediatric HIV BioBank is to contribute to the furthering of scientific knowledge about vertical HIV infection. To achieve this aim, the BioBank processes, stores, and provides distinct samples from HIV/AIDS children to research projects free of charge. Strict compliance to ethical norms is always guaranteed. At present the Pediatric HIV BioBank has 429 vials containing different sample types from 243 vertically HIV-infected children. The Pediatric HIV BioBank represents a novel approach to HIV research that might be of general interest not only for basic and clinical research teams working with HIV, but also for those groups trying to establish large networks focused on researching specific clinical problems. It also represents a model to stimulate cooperative research on specific clinical problems. The main objective of this article is to show the structure and function of the Pediatric HIV BioBank that allow it to efficiently provide samples to different research projects in Spain and in other countries.

The Spanish HIV BioBank: a model of cooperative HIV research

Background

The collection of samples from HIV-infected patients is the beginning of the chain of translational research. To carry out quality research that could eventually end in a personalized treatment for HIV, it is essential to guarantee the availability, quality and traceability of samples, under a strict system of quality management.

Methods

The Spanish HIV BioBank was created with the objectives of processing, storing and providing distinct samples from HIV/AIDS patients, categorized according to strictly defined characteristics, free of charge to research projects. Strict compliance to ethical norms is always guaranteed.

Results

At the moment, the HIV BioBank possesses nearly 50,000 vials containing different prospective longitudinal study sample types. More than 1,700 of these samples are now used in 19 national and international research projects.

Conclusion

The HIV BioBank represents a novel approach to HIV research that might be of general interest not only for basic and clinical research teams working on HIV, but also for those groups trying to establish large networks focused on research on specific clinical problems. It also represents a model to stimulate cooperative research among large numbers of research groups working as a network on specific clinical problems. The main objective of this article is to show the structure and function of the HIV BioBank that allow it to very efficiently release samples to different research project not only in Spain but also in other countries.

[Prevalence of resistance to antiretroviral drugs in Spain]

INTRODUCTION

The development of resistance to antiretroviral therapy (ART) reduces the effectiveness of these drugs in HIV-infected children.

METHODS

We performed a cross-sectional study in 86 vertically HIV-infected children, divided into four groups according to prior treatment: group 1: nucleoside reverse transcriptase inhibitor (NRTI), group 2: NRTI and non-nucleoside reverse transcriptase inhibitor (NNRTI), group 3: NRTI and protease inhibitor (PI), group 4: NRTI, NNRTI and PI.

RESULTS

In group 1 (11 children), the median treatment duration was 35 months (26 to 108). Nucleoside-associated mutations (NAMs) were found in 10 of these patients and the Q151M multiresistance mutation was found in two. The three children in group 2 were treated for 9, 32 and 42 months with NRTI and NNRTI. One child showed three NAMs and another showed Q151M. Two children had the K103N mutation. Group 3 (36 children) received treatment with NRTI and PI for 48.0 +/- 27.6 and 23.0 +/- 14.6 months, respectively. NAMs were observed in 94 % of the patients in this group, and one child showed the Q151M mutation. In group 4 (36 children) total treatment duration was 70.0 +/- 36.1 months (13.0 +/- 12.1 months with NNRTI, and 39.0 +/- 14.3 months with PI). NAMs were observed in all patients in this group, and Q151M was found in three children. K103N and Y181C were detected in 24 (67%) and 10 (28%) of the children respectively, while 32 (90%) showed primary mutations to PI.

CONCLUSIONS

A high prevalence of resistance mutations to NRTI and early appearance of resistance to NNRTI were observed in treated children.

Lack of Association of HIV-1 Biological or Molecular Properties With Neurotropism for Brain Cells

Despite HAART, a significant number of HIV-1-infected patients develop neurological complications. However, the presence of specific neurotropic HIV-1 strains, the extent of viral replication in the brain, and the type of cells infected remain controversial issues. To address this controversy we have analyzed different V3 loop sequences of viral isolates from four vertically HIV-1-infected children who developed HIV-1-related encephalopathy. Moreover, we have determined that some biological and molecular properties of HIV-1 might contribute to AIDS neurological dysfunctions. We detected very different HIV-1 isolates (X4 and R5) in the brain despite no great differences in clinical, pathological, or immunological parameters. In vitro, no differences in replicative competence in glial or neuroblastoma cells were observed between virus isolated from the blood of children with or without clinical neurological symptoms. The expression of both CXCR4 and CCR5 RNAs was observed in the brain independently of HIV-1 infection and viral strain predominant in this location. Our results failed to show a particular phenotypic property of the HIV-1 virus that might explain its neurovirulence and/or neurotropism.

A comparison of fluorescent in situ hybridization and multiplex short tandem repeat polymerase chain reaction for quantifying chimerism after stem cell transplantation

BACKGROUND AND OBJECTIVES

Despite the great utility of chimerism analysis after allogeneic stem cell transplantation, a gold standard method for its quantification has not yet been defined. The objective of the present investigation was to compare the sensitivity (detection limit) and the quantification accuracy of fluorescent in situ hybridization with specific probes for the sex chromosomes (XY-FISH) and multiplex short tandem repeat polymerase chain reaction (STR-PCR) revealed by capillary electrophoresis for the quantification of chimerism after stem cell transplantation.

DESIGN AND METHODS

A first experiment was performed on two sets of artificial cell mixtures from two sex-mismatched healthy donors mixed in different proportions (% male: 100, 75, 50, 25, 10, 5, 3, 1, 0.1, 0). In a second experiment, 58 samples obtained from 10 selected patients with different clinical courses and chimerism evolution after sex-mismatched stem cell transplantation, which had been studied by XY-FISH, were retrospectively analyzed by STR-PCR. In a third experiment, 60 unselected prospective samples belonging to 15 patients (5 of whom had also been included in the retrospective study) were analyzed by both XY-FISH and STR-PCR.

RESULTS

Both techniques showed high quantification accuracy and were highly reproducible. The sensitivity of both approaches reached 1% under standard conditions. Moreover, the use of long injection times for the capillary electrophoresis (30 and 50s vs. the standard 10s) resulted in an increase of sensitivity of the STR-PCR assay up to 0.1%, which has interesting clinical implications.

INTERPRETATION AND CONCLUSIONS

Considering the high sensitivity and quantification accuracy of multiplex STR-PCR and the fact that this assay is sex-independent and can be applied to virtually all patients, STR-PCR could be considered as the method of choice for chimerism quantification after stem cell transplantation when high sensitivity is not a requirement.

Mutations at codons 54 and 82 of HIV protease predict virological response of HIV-infected children on salvage lopinavir/ritonavir therapy

BACKGROUND

Lopinavir/ritonavir is a protease inhibitor (PI) that has shown great effectiveness as salvage therapy in PI-experienced HIV-infected children.

OBJECTIVES

To study whether mutations in the HIV-1 protease gene can reliably predict virological responses to salvage therapy with lopinavir/ritonavir in HIV-infected children.

PATIENTS AND METHODS

We carried out a prospective study in 56 HIV-infected children. PI-associated resistance mutations were determined by genotypic testing and were scored according to the IAS-USA guidelines 2005.

RESULTS

Children with a 'lopinavir mutation score' (LMS) > or = 6 had a negative association for achieving viral load (VL) control [undetectable viral load (uVL) < or = 400 copies/mL] and maintaining uVL for at least 6 months. Moreover, children with protease-associated mutations (PRAMs) > or = 2 had a negative association for achieving VL control but not for maintaining uVL for at least 6 months. The relative proportion (RP) to uVL was 0.32 (CI95%: 0.16; 0.33; P = 0.002) in children with I54V (46% of total) and 0.48 (CI95%: 0.24; 0.97; P = 0.041) in children with V82A/F (52% of total). Children with I54V and V82A/F had higher prevalence of lopinavir-associated resistance mutations and showed RP of 0.36 (CI95%: 0.17; 0.76; P = 0.007) for achieving uVL.

CONCLUSIONS

LMS and PRAMs in HIV-infected children were associated with virological failure in pre-treated HIV-infected children on salvage therapy with lopinavir/ritonavir. Moreover, I54V and V82A/F led to the poorest virological response.