DTG

Co-pyrolysis characteristics of municipal sewage sludge and hazelnut shell by TG-DTG-MS and residue analysis.[Pubmed:28236506]

Waste Manag. 2017 Apr;62:91-100.

Co-pyrolysis characteristics of municipal sewage sludge and hazelnut shell blend have been studied in this work. The behavior of co-pyrolysis was researched by a method of multi-heating rates and different blend ratios to analyze thermal decomposition stages. The experimental data of the blended samples in TG-DTG plots were compared with calculated data to investigate the interactions during co-pyrolysis. The bio-chars investigated by SEM and FTIR spectra were used to examine the physical and chemical changes. The results showed there are four thermal decomposition stages during co-pyrolysis, with hydrocarbon transforming to gas evolution in the second and the third stages. The inhibitive interaction occurred between 260 and 400 degrees C and the accelerative interaction occurred between 450 and 900 degrees C during co-pyrolysis. The activation energy of the blended sample was 51.97-178.84kJ/mol in the second stage and 207.04-630.73kJ/mol in the third stage calculated by DAEM.

Effect on HIV-1 viral replication capacity of DTG-resistance mutations in NRTI/NNRTI resistant viruses.[Pubmed:27130466]

Retrovirology. 2016 Apr 30;13(1):31.

BACKGROUND: Recommended regimens for HIV-positive individuals include the co-administration of dolutegravir (DTG) with two reverse transcriptase inhibitors (RTIs). Although rare, emerging resistance against DTG is often associated with the R263K substitution in integrase. In-vitro-selected R263K was associated with impaired viral replication capacity, DNA integration, and integrase strand-transfer activity, especially when accompanied by the secondary mutation H51Y. Given the reduced fitness of RTI-resistant viruses, we investigated potential impacts on viral replication of combining R263K and H51Y/R263K with major RTI-resistance substitutions including K65R, L74V, K103N, E138K, and M184I/V. RESULTS: We combined the R263K or H51Y/R263K with RTI-resistance mutations into the proviral plasmid pNL4.3 and measured the resulting viral infectiousness, replication capacity, and ability to integrate viral DNA into host cells. Infectiousness was determined by luciferase assay in TZM-bl cells. Replicative capacity was monitored over 7 days and viral DNA integration was studied by real-time Alu-qPCR in PM1 cells. We found that viral infectiousness, replication capacities and integration levels were greatly reduced in triple mutants, i.e. H51Y/R263K plus a RT mutation, and moderately reduced in double mutants, i.e. R263K plus a RT mutation, compared to wild-type and single RT-mutant viruses. CONCLUSIONS: Our findings help to explain the absence of RTI mutations in individuals who experienced DTG-treatment failure.

Dolutegravir(DTG, S/GSK1349572) combined with other ARTs is superior to RAL- or EFV-based regimens for treatment of HIV-1 infection: a meta-analysis of randomized controlled trials.[Pubmed:27617024]

AIDS Res Ther. 2016 Sep 8;13(1):30.

BACKGROUND: The first-generation integrase inhibitors (INIs) raltegravir (RAL) and elvitegravir (EVG) have shown efficacy against HIV infection, but they have the limitations of once-more daily dosing and extensive cross-resistance. Dolutegravir (DTG, S/GSK1349572), a second-generation drug that overcomes such shortcomings, is under spotlight. The purpose of this study is to review the evidence for DTG use in clinical settings, including its efficacy and safety. METHODS: PubMed, EMbase, Ovid, Web of Science, Science Direct, and related websites were screened from establishment until July 2013, and scientific meeting proceedings were manually searched. Two reviewers independently screened 118 citations repeatedly to identify randomized controlled trials comparing the efficacy and safety of DTG-based regimen with those of RAL- or elvitegravir-based regimens. Using the selected studies with comparable outcome measures and indications, we performed a meta-analysis based on modified intention-to-treat (mITT), on-treatment (OT), and as-treated (AT) virological outcome data. Independent data extraction and quality assessment were conducted. RESULTS: Four unique studies were included with the use of DTG in antiretroviral therapy-naive patients. In therapy-naive patients, DTG combined with abacavir/lamivudine (ABC/3TC) or tenofovir/emtricitabine (TDF/FTC) resulted in a significantly better virological outcome with a mITT relative risk (RR)of 1.07 (95 % confidence interval (95 % CI 1.03-1.12). Evidence further supported use of DTG had a better virological suppression in the 50 mg once daily group (mITT RR 1.07; 95 % CI 1.03-1.12) as well as in the sub-analysis in dolutegravir/efavirenz(DTG/EFV) and dolutegravir/raltegravir (DTG/RAL) groups (RR 1.09, 95 % CI 1.03-1.15; RR 1.06, 95 % CI 0.98-1.15, respectively). In the matter of safety of DTG-based regimen, the risk of any event was RR 0.98 (95 % CI 0.94-1.01), the risk of serious adverse events (AEs) was RR 0.84 (95 % CI 0.62-1.15), and the risk of drug-related serious AEs was RR 0.33 (95 % CI 0.13-0.79). CONCLUSION: In general, DTG 50 mg given once daily combined with an active background drug is a better choice in terms of both efficacy and safety.

Synthesis and binding characteristics of potential SPECT imaging agents for sigma-1 and sigma-2 binding sites.[Pubmed:8496936]

J Med Chem. 1993 Mar 5;36(5):566-71.

2-, 3-, and 4-idophenyl derivatives of the high-affinity sigma ligand N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (1) were synthesized in two to four steps starting from N-methyl-2-(1-pyrrolidinyl)ethylamine. These compounds were evaluated for their capacity to label both sigma 1 and sigma 2 subtypes in vitro. sigma-1 binding affinity was determined by measuring competition with [3H]-(+)-pentazocine binding to guinea pig brain membranes while sigma 2 binding was evaluated through competition with [3H]DTG binding to rat liver membranes in the presence of excess dextrallorphan. The binding data revealed that N-[2-(3-iodophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (2) and N-[2-(4-iodophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (3) displayed almost identical binding affinity at sigma 1 sites to the parent compound 1. This suggests that the 3- or 4-iodo group can effectively substitute for the 3,4-dichloro substituents of 1. In this series of compounds, Ki's at the sigma 1 site varied from 2.0 nM for N-(4-iodobenzyl)-N-methyl-2-(1-pyrrolidinyl)ethylamine (6) to 26.6 nM for N-(2-iodobenzyl)-N-methyl-2-(1-pyrrolidinyl)ethylamine (4). Ki's for sigma 2 site ranged from 8.1 nM for 1 to 220 nM for N-(3-bromobenzyl)-N-methyl-2-(1-pyrrolidinyl)ethylamine (11) while the sigma 2/sigma 1 ratio varied from 1.8 for 4 to 25 for 11. Comparing halogen substitution, the trend Cl = I > Br > F was observed for binding affinity at sigma 1 sites; no such trend was observed at sigma 2 sites. On the basis of the binding data, compounds 2 and 3 were selected for labeling with 123I. Thus, treatment of the corresponding 3- and 4-(tributylstannyl) intermediates (7 and 8) with Na123I in the presence of excess CH3CO3H furnished [123I]-2 and [123I]-3 in up to 70% radiochemical yield. Preliminary in vitro binding with [123I]-3 indicated up to 97% specific binding with guinea pig brain membranes.