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Abstract Background Members of the Anopheles punctulatus group (AP group) are the primary vectors of human malaria in Papua New Guinea. The AP group includes 13 sibling species, most of them morphologically indistinguishable. Understanding why only certain species are able to transmit malaria requires a better comprehension of their evolutionary history. In particular, understanding relationships and divergence times among Anopheles species may enable assessing how malaria-related traits (e.g. blood feeding behaviours, vector competence) have evolved. Methods DNA sequences of 14 mitochondrial (mt) genomes from five AP sibling species and two species of the Anopheles dirus complex of Southeast Asia were sequenced. DNA sequences from all concatenated protein coding genes (10,770 bp) were then analysed using a Bayesian approach to reconstruct phylogenetic relationships and date the divergence of the AP sibling species. Results Phylogenetic reconstruction using the concatenated DNA sequence of all mitochondrial protein coding genes indicates that the ancestors of the AP group arrived in Papua New Guinea 25 to 54 million years ago and rapidly diverged to form the current sibling species. Conclusion Through evaluation of newly described mt genome sequences, this study has revealed a divergence among members of the AP group in Papua New Guinea that would significantly predate the arrival of humans in this region, 50 thousand years ago. The divergence observed among the mtDNA sequences studied here may have resulted from reproductive isolation during historical changes in sea-level through glacial minima and maxima. This leads to a hypothesis that the AP sibling species have evolved independently for potentially thousands of generations. This suggests that the evolution of many phenotypes, such as insecticide resistance will arise independently in each of the AP sibling species studied here.

The BICSTaR (BICtegravir Single Tablet Regimen) study is investigating the effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in people with human immunodeficiency virus (HIV) treated in routine clinical practice. BICSTaR is an ongoing, prospective, observational cohort study across 14 countries. Treatment-naïve (TN) and treatment-experienced (TE) people with HIV (≥18 years of age) are being followed for 24 months. We present an analysis of the primary endpoint (HIV-1 RNA < 50 copies/mL; missing-equals-excluded [M = E]) at month 12 in the BICSTaR Canada cohort, including secondary (CD4 count, CD4/CD8 ratio, safety/tolerability) and exploratory (persistence, treatment satisfaction) endpoints. In total, 201 participants were enrolled in the BICSTaR Canada cohort. The analysis population included 170 participants (TN, n = 10; TE, n = 160), with data collected between November 2018 and September 2020. Of the participants, 88% were male, 72% were White, and 90% had ≥ 1 comorbid condition(s). Median (quartile [Q]1-Q3) age was 50 (39-58) years and baseline CD4 count was 391.5 (109.0-581.0) cells/µL in TN participants and 586.0 (400.0-747.0) cells/µL in TE participants. After 12 months of B/F/TAF treatment, HIV-1 RNA was < 50 copies/mL in 100% (9/9) of TN-active participants and 97% (140/145) of TE-active participants (M = E analysis). Median (Q1-Q3) CD4 cell count increased by +195 (125-307) cells/µL in TN participants and by + 30 (-50 to 123) cells/µL in TE participants. Persistence on B/F/TAF was high through month 12 with 10% (1/10) of TN and 7 % (11/160) of TE participants discontinuing B/F/TAF within 12 months of initiation of treatment. No resistance to B/F/TAF emerged. Study drug-related adverse events occurred in 7% (12/169) of participants, leading to B/F/TAF discontinuation in 4 of 169 participants. Improvements in treatment satisfaction were observed in TE participants. B/F/TAF demonstrated high levels of effectiveness, persistence, and treatment satisfaction, and was well tolerated through month 12 in people with HIV treated in routine clinical practice in Canada., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Because antiretroviral therapy (ART) is allowing people living with human immunodeficiency virus (PLWH) to survive longer, they are developing more age-related comorbidities. We evaluated the effects of age and gender on the burden of age-related comorbidities among PLWH. In this retrospective real-world study, de-identified data were extracted from the medical charts of 2000 HIV-positive adults on ART across 10 sites in Canada. The prevalence of age-related comorbidities was determined in 6 age subgroups (<30, 30-39, 40-49, 50-59, 60-69, and ≥70 years). The effects of gender on these comorbidities were also examined. Risks of cardiovascular disease and chronic kidney disease (CKD) were calculated using the Framingham and D:A:D equations. Most persons were White (68%), male (87%), and virologically suppressed (94%). The mean age was 50.3 years (57% aged ≥50 years), and mean CD4+ T-cell count was 616 cells/mm3. The most common comorbidities were neuropsychiatric symptoms (61%), overweight/obesity (43%), liver disease (37%), and dyslipidemia (37%). The mean number of comorbidities increased across age subgroups (P < .001). Across all age subgroups, the prevalence of hypertension (P = .04), dyslipidemia (P = .04), CKD (P = .03), bone fragility (P = .03), and depression (P = .02) differed between males and females. Both age (P < .001) and gender (P < .001) impacted cardiovascular disease and CKD risk. Age and gender influenced the burden, types, and risks of age-related comorbidities in PLWH in this Canadian cohort. These comorbidities should be diagnosed and treated in routine clinical practice., Competing Interests: J.M.B. received conference sponsorship from Gilead Sciences and ViiV Healthcare; consultancy fees from Gilead Sciences, ViiV Healthcare, and Merck; and speaker fees from Gilead Sciences. J.-G.B. reports grants to his institution from ViiV Healthcare, Gilead Sciences, and Merck and honoraria for consultancy, ad-boards, or conferences from ViiV Healthcare, Gilead Sciences, and Merck. J.J.d.W. served on advisory boards and as a speaker for ViiV Healthcare and Gilead Sciences. C.F. received funds for the development of hepatitis C virus learning modules for iCare Education Inc. (paid to Dr. Fraser) and funding for educational conferences, continuing medical education presentations, and clinical trials from AbbVie, Gilead Sciences, Merck, and ViiV Healthcare (paid to institution). G.R. is member of medical advisory boards for Gilead Sciences, Moderna, ViiV Healthcare, and Merck. R.T. received honoraria from Gilead Sciences for presentations, consultations, and advisory boards. His institution receives funding from Gilead Sciences for its HIV and preexposure prophylaxis databases and for intervention projects. K.L. received advisory board fees from ViiV Healthcare and Gilead Sciences. M.S. received consultation fees on advisory boards for Gilead Sciences and Merck. J.P. supplied data collection and management services, which were funded by Gilead Sciences Canada. R.-P.L. is an employee of Gilead Sciences Canada. H.T. is a former employee of Gilead Sciences Canada. K.J.K. is an employee of Gilead Sciences, Inc. and a former employee of Gilead Sciences Canada. A.W. received consulting fees and honoraria from Merck, Gilead Sciences, and ViiV Healthcare; received funding for regional and provincial programming from Merck, Gilead Sciences, and ViiV Healthcare; and currently participates in clinical trials for Merck, Gilead Sciences, and ViiV Healthcare. H.L. and H.J. have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

The Alaska blackfish ( Dallia pectoralis ) remains active at cold temperatures when experiencing aquatic hypoxia without air access. To discern the cardiophysiological adjustments that permit this behaviour, we quantified the effect of acclimation from 15°C to 5°C in normoxia (15N and 5N fish), as well as chronic hypoxic submergence (6-8 weeks; ∼6.3-8.4 kPa; no air access) at 5°C (5H fish), on in vivo and spontaneous heart rate ( f H ), electrocardiogram, ventricular action potential (AP) shape and duration (APD), the background inward rectifier ( I ) K K1 ) and rapid delayed rectifier ( I Kr ) K + currents and ventricular gene expression of proteins involved in excitation-contraction coupling. In vivo f H (3.5-fold; K I K1 and I (7.4-fold; K Kr were not upregulated in 5N fish. By contrast, chronic hypoxic submergence elicited a shortening of QT interval and APD, driven by an upregulation of I Kr (2.9-fold; K kcnh6 (3.5-fold; K v 11.2 of I Kr ), kcnj12 (7.4-fold; K ir 2.2 of I K1 ) and kcnj14 (2.9-fold; K ir 2.4 of I K1 ). 5H fish also exhibited a unique gene expression pattern that suggests modification of ventricular Ca 2+ cycling. Overall, the findings reveal that Alaska blackfish exposed to chronic hypoxic submergence prioritize the continuation of cardiac performance to support an active lifestyle over reducing cardiac ATP demand., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

The study of the microbial communities has gained traction in recent years with the advent of next-generation sequencing with, or without, PCR-based amplification of the 16S ribosomal RNA region. Such studies have been applied to topics as diverse as human health and environmental ecology. Fewer studies have investigated taxa outside of bacteria, however. We present here data demonstrating the utility of studying taxa outside of bacteria including algae, diatoms, archaea and fungi. Here, we show how location along the Cuyahoga River as well as a transient rainfall event heavily influence the microbial composition. Our data reveal how individual OTUs vary between samples and how the patterns of OTU abundance can accurately predict sampling location. The clustering of samples reveals that these taxa are all sensitive to water conditions in unique ways and demonstrate that, for our dataset, algae was most distinctive between sample groups, surpassing bacteria. Diversity between sampling sites could allow studies investigating pollution or water quality to identify marker OTUs or patterns of OTU abundance as indicators to assess environmental conditions or the impact of human activity. We also directly compare data derived from primers amplifying distinct taxa and show that taxa besides bacteria are excellent indicators of water condition.

Background: Simplified dosing regimens are important for patients who face challenges in adhering to HIV-1 therapy. We investigated the safety and virological efficacy of switching to once-daily abacavir/dolutegravir/lamivudine (ABC/DTG/3TC)., Methods: The STRIIVING study was a randomized, open-label, Phase IIIb study in adults with HIV-1 RNA <50 copies/ml on antiretroviral therapy (ART) at enrolment (ClinicalTrials.gov identifier, NCT02105987). Subjects were randomly assigned to switch to ABC/DTG/3TC once daily for 48 weeks (early-switch group) or continue current ART for 24 weeks and then switch to ABC/DTG/3TC (late-switch group). The primary end point was the proportion of subjects with HIV-1 RNA <50 copies/ml at week 24., Results: Of 553 subjects enrolled, 275 were randomly assigned to switch immediately to ABC/DTG/3TC and 278 continued on current ART. At week 24, 85% and 88% of subjects who switched to ABC/DTG/3TC or remained on current ART, respectively, were virologically suppressed, indicating that ABC/DTG/3TC was non-inferior (difference in proportion, -3.4%; 95% CI -9.1, 2.4). At week 48, 83% and 92% were virologically suppressed in the early- and late-switch groups, respectively. Adverse events were reported more frequently with ABC/DTG/3TC (66%) than with current ART (47%) by week 24, and in the late-switch group, 60% of subjects reported adverse events post-switch. Pharmacokinetic data supported immediate switch. HIV Treatment Satisfaction Questionnaire scores improved in participants switching to ABC/DTG/3TC versus current ART., Conclusions: Data demonstrating non-inferiority of switching to ABC/DTG/3TC versus continuing current ART support ABC/DTG/3TC as an option when considering switch regimens in HIV-1-infected adults with stable viral suppression.

Objectives To investigate whether maternal health risk assessment and behavioral intervention in the neonatal intensive care unit (NICU) improves women's health care seeking and health behaviors following the birth of a very low birth weight (VLBW) infant. Methods Using a quasi-experimental non-equivalent control group pretest/posttest design, 80 women who had given birth to a VLBW infant that was admitted to the NICU were enrolled into one of two cohorts: 40 into a 'Minimal Intervention' cohort, who received a single session risk assessment and health education pamphlets, and 40 into an 'Enhanced Intervention' cohort, who received five counseling sessions targeting identified risks. The proportion of women with specific health care seeking and health behaviors in the two cohorts were compared at baseline and 3- and 9-months post-intervention. Results Women in the Enhanced Intervention cohort were more likely to attend the postpartum visit (73 % vs. 48 %; p = 0.04), ingest folic acid daily (65 % vs. 19 %, p < 0.001), and correctly and consistently use a method of contraception (82 % vs. 63 %, p = 0.03) over the 9-month follow-up period. In multivariate analysis, the between-cohort differences in daily folic acid use (aOR = 3.45, 95 % CI 1.61-7.40) and correct and consistent use of a method of contraception (aOR = 1.46, 95 % CI 1.05-2.06) remained statistically significant at 9-months and the reduction in risk of unintended pregnancy nearly achieved statistical significance (aOR = 0.62, 95 % CI 0.12-1.0). Conclusions for Practice This study provides support for the implementation of maternal risk assessment and behavioral intervention in the NICU setting to promote women's positive health care seeking and health behaviors.

Understanding mosquito host choice is important for assessing vector competence or identifying disease reservoirs. Unfortunately, the availability of an unbiased method for comprehensively evaluating the composition of insect blood meals is very limited, as most current molecular assays only test for the presence of a few pre-selected species. These approaches also have limited ability to identify the presence of multiple mammalian hosts in a single blood meal. Here, we describe a novel high-throughput sequencing method that enables analysis of 96 mosquitoes simultaneously and provides a comprehensive and quantitative perspective on the composition of each blood meal. We validated in silico that universal primers targeting the mammalian mitochondrial 16S ribosomal RNA genes (16S rRNA) should amplify more than 95% of the mammalian 16S rRNA sequences present in the NCBI nucleotide database. We applied this method to 442 female Anopheles punctulatus s. l. mosquitoes collected in Papua New Guinea (PNG). While human (52.9%), dog (15.8%) and pig (29.2%) were the most common hosts identified in our study, we also detected DNA from mice, one marsupial species and two bat species. Our analyses also revealed that 16.3% of the mosquitoes fed on more than one host. Analysis of the human mitochondrial hypervariable region I in 102 human blood meals showed that 5 (4.9%) of the mosquitoes unambiguously fed on more than one person. Overall, analysis of PNG mosquitoes illustrates the potential of this approach to identify unsuspected hosts and characterize mixed blood meals, and shows how this approach can be adapted to evaluate inter-individual variations among human blood meals. Furthermore, this approach can be applied to any disease-transmitting arthropod and can be easily customized to investigate non-mammalian host sources.

Anopheles mosquitoes are the vectors of several human diseases including malaria. In many malaria endemic areas, several species of Anopheles coexist, sometimes in the form of related sibling species that are morphologically indistinguishable. Determining the size and organization of Anopheles populations, and possible ongoing gene flow among them is important for malaria control and, in particular, for monitoring the spread of insecticide resistance alleles. However, these parameters have been difficult to evaluate in most Anopheles species due to the paucity of genetic data available. Here, we assess the extent of contemporary gene flow and historical variations in population size by sequencing and de novo assembling the genomes of wild-caught mosquitoes from four species of the Anopheles punctulatus group of Papua New Guinea. Our analysis of more than 50 Mb of orthologous DNA sequences revealed no evidence of contemporary gene flow among these mosquitoes. In addition, investigation of the demography of two of the An. punctulatus species revealed distinct population histories. Overall, our analyses suggest that, despite their similarities in morphology, behaviour and ecology, contemporary sympatric populations of An. punctulatus are evolving independently., (© 2015 John Wiley & Sons Ltd.)

Background: Phase I and phase II HIV-1 vaccine trials have revealed increases in risky sexual activity among study subjects during the trials, perhaps because the subjects believe that the vaccine being tested is efficacious; subjects may thus suffer harm from their participation. We evaluated the sexual behaviour of Canadian men who have sex with men (MSM) who participated in the phase III Vax004 trial of an HIV-1 vaccine., Methods: Using self-reports of sexual behaviours during the 6 months before trial entry as a baseline, we determined changes in reported sexual behaviour after 6, 12 and 18 months of participation in the trial., Results: Of 291 HIV-seronegative MSM enrolled from July to October 1999, 260 (89%) completed 18 months of follow-up, 19 (7%) experienced seroconversion, and 12 (4%) did not complete follow-up. Unprotected receptive anal intercourse during the previous 6 months with partners whose HIV-1 serostatus was positive or unknown was reported by 21% of men at enrollment and by 27% at any point during 18 months of follow-up. No increase in this behaviour from baseline was reported by participants, including among men who were motivated to enroll because of expected protection from HIV-1 infection, men who believed they had received the vaccine, men who believed that the vaccine had greater than 50% efficacy, or men who believed that they had received the vaccine and that vaccine efficacy was greater than 50%., Interpretation: MSM can be successfully enrolled in HIV-1 vaccine efficacy trials without evident increases in those sexual behaviours most associated with HIV-1 risk.

A series of P1/P1' substituted cyclic urea analogues were prepared in an attempt to increase the intra-cellular antiviral potency of the nonsymmetrical 3-aminoindazoles DMP 850 and DMP 851. The effect of alkyl substitution of the P1/P1' residues on cellular antiviral potency, protein binding, resistance profile and pharmacokinetics are described.

Human immunodeficiency virus (HIV) protease inhibitors (PIs) are important components of many highly active antiretroviral therapy regimens. However, development of phenotypic and/or genotypic resistance can occur, including cross-resistance to other PIs. Development of resistance takes place because trough levels of free drug are inadequate to suppress preexisting resistant mutant variants and/or to inhibit de novo-generated resistant mutant variants. There is thus a need for new PIs, which are more potent against mutant variants of HIV and show higher levels of free drug at the trough. We have optimized a series of substituted sulfonamides and evaluated the inhibitors against laboratory strains and clinical isolates of HIV type 1 (HIV-1), including viruses with mutations in the protease gene. In addition, serum protein binding was determined to estimate total drug requirements for 90% suppression of virus replication (plasma IC(90)). Two compounds resulting from our studies, designated DPC 681 and DPC 684, are potent and selective inhibitors of HIV protease with IC(90)s for wild-type HIV-1 of 4 to 40 nM. DPC 681 and DPC 684 showed no loss in potency toward recombinant mutant HIVs with the D30N mutation and a fivefold or smaller loss in potency toward mutant variants with three to five amino acid substitutions. A panel of chimeric viruses constructed from clinical samples from patients who failed PI-containing regimens and containing 5 to 11 mutations, including positions 10, 32, 46, 47, 50, 54, 63, 71, 82, 84, and 90 had mean IC(50) values of <20 nM for DPC 681 and DPC 681, respectively. In contrast, marketed PIs had mean IC(50) values ranging from 200 nM (amprenavir) to >900 nM (nelfinavir).

Efavirenz (also known as DMP 266 or SUSTIVA) is a potent nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity and of HIV-1 replication in vitro and in vivo. Most patients on efavirenz-containing regimens have sustained antiviral responses; however, rebounds in plasma viral load have been observed in some patients in association with the emergence of mutant strains of HIV-1. Virus isolates from the peripheral blood mononuclear cells (PBMCs) of patients with such treatment failures, as well as recombinant viruses incorporating viral sequences derived from patient plasma, show reduced in vitro susceptibility to efavirenz in association with mutations in the RT gene encoding K103N, Y188L, or G190S/E substitutions. Patterns of RT gene mutations and in vitro susceptibility were similar in plasma virus and in viruses isolated from PBMCs. Variant strains of HIV-1 constructed by site-directed mutagenesis confirmed the role of K103N, G190S, and Y188L substitutions in reduced susceptibility to efavirenz. Further, certain secondary mutations (V106I, V108I, Y181C, Y188H, P225H, and F227L) conferred little resistance to efavirenz as single mutations but enhanced the level of resistance of viruses carrying these mutations in combination with K103N or Y188L. Viruses with K103N or Y188L mutations, regardless of the initial selecting nonnucleoside RT inhibitor (NNRTI), exhibited cross-resistance to all of the presently available NNRTIs (efavirenz, nevirapine, and delavirdine). Some virus isolates from nevirapine or delavirdine treatment failures that lacked K103N or Y188L mutations remained susceptible to efavirenz in vitro, although the clinical significance of this finding is presently unclear.

A series of 4-alkenyl and 4-alkynyl-3, 4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones were found to be potent non-nucleoside reverse transcriptase inhibitors (NNRTIs) of human immunodeficiency virus type-1 (HIV-1). The 4-alkenyl-3, 4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones DPC 082 and DPC 083 and the 4-alkynyl-3, 4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones DPC 961 and DPC 963 were found to exhibit low nanomolar potency toward wild-type RF virus (IC(90) = 2.0, 2.1, 2.0, and 1.3 nM, respectively) and various single and many multiple amino acid substituted HIV-1 mutant viruses. The increased potency is combined with favorable plasma serum protein binding as demonstrated by improvements in the percent free drug in human plasma when compared to efavirenz: 3.0%, 2.0%, 1.5%, 2. 8%, and 0.2-0.5% for DPC 082, DPC 083, DPC 961, DPC 963, and efavirenz, respectively.

Using the structural information gathered from the X-ray structures of various cyclic urea/HIVPR complexes, we designed and synthesized many nonsymmetrical P2/P2'-substituted cyclic urea analogues. Our efforts concentrated on using an indazole as one of the P2 substituents since this group imparted enzyme (Ki) potency as well as translation into excellent antiviral (IC90) potency. The second P2 substituent was used to adjust the physical and chemical properties in order to maximize oral bioavailability. Using this approach several very potent (IC90 11 nM) and orally bioavailable (F% 93-100%) compounds were discovered (21, 22). However, the resistance profiles of these compounds were inadequate, especially against the double (I84V/V82F) and ritonavir-selected mutant viruses. Further modification of the second P2 substituent in order to increase H-bonding interactions with the backbone atoms of residues Asp 29, Asp 30, and Gly 48 led to analogues with much better resistance profiles. However, these larger analogues were incompatible with the apparent molecular weight requirements for good oral bioavailability of the cyclic urea class of HIVPR inhibitors (MW < 610).

We present several novel P1/P1' substituents that can replace the characteristic benzyl P1/P1' moiety of the cyclic urea based HIV protease inhibitor series. These substituents typically provide 5-10-fold improvements in binding affinity compared to the unsubstituted benzyl analogs. The best substituent was the 3,4-(ethylenedioxy)benzyl group. Proper balancing of the molecule's lipophilicity facilitated the transfer of this improved binding affinity into a superior cellular antiviral activity profile. Several analogs were evaluated further for protein binding and resistance liabilities. Compound 18 (IC90 = 8.7 nM) was chosen for oral bioavailability studies based on its log P and solubility profile. A 10 mg/kg dose in dogs provided modest bioavailability with Cmax = 0.22 microg/mL. X-ray crystallographic analysis of two analogs revealed several interesting features responsible for the 3,4-(ethylenedioxy)benzyl-substituted analog's potency: (1) Comparing the two complexes revealed two distinct binding modes for each P1/P1' substituent; (2) The ethylenedioxy moieties are within 3.6 A of Pro 81 providing additional van der Waals contacts missing from the parent structure; (3) The enzyme's Arg 8 side chain moves away from the P1 substituent to accommodate the increased steric volume while maintaining a favorable hydrogen bond distance between the para oxygen substituent and the guanidine NH.