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1.
J Infect Dis ; 230(1): e4-e16, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39052718

ABSTRACT

BACKGROUND: Mutations present in emerging SARS-CoV-2 variants permit evasion of neutralization with prototype vaccines. A novel Omicron BA.1 subvariant-specific vaccine (NVX-CoV2515) was tested alone or as a bivalent preparation with the prototype vaccine (NVX-CoV2373) to assess antibody responses to SARS-CoV-2. METHODS: Participants aged 18 to 64 years immunized with 3 doses of prototype mRNA vaccines were randomized 1:1:1 to receive a single dose of NVX-CoV2515, NVX-CoV2373, or the bivalent mixture in a phase 3 study investigating heterologous boosting with SARS-CoV-2 recombinant spike protein vaccines. Immunogenicity was measured 14 and 28 days after vaccination for the SARS-CoV-2 Omicron BA.1 sublineage and ancestral strain. Safety profiles of vaccines were assessed. RESULTS: Of participants who received trial vaccine (N = 829), those administered NVX-CoV2515 (n = 286) demonstrated a superior neutralizing antibody response to BA.1 vs NVX-CoV2373 (n = 274) at day 14 (geometric mean titer ratio, 1.6; 95% CI, 1.33-2.03). Seroresponse rates were 73.4% (91/124; 95% CI, 64.7-80.9) for NVX-CoV2515 vs 50.9% (59/116; 95% CI, 41.4-60.3) for NVX-CoV2373. All formulations were similarly well tolerated. CONCLUSIONS: NVX-CoV2515 elicited a superior neutralizing antibody response against the Omicron BA.1 subvariant as compared with NVX-CoV2373 when administered as a fourth dose. Safety data were consistent with the established safety profile of NVX-CoV2373. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov (NCT05372588).


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , COVID-19 Vaccines , COVID-19 , Immunization, Secondary , Immunogenicity, Vaccine , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , Adult , SARS-CoV-2/immunology , SARS-CoV-2/genetics , Antibodies, Viral/blood , Antibodies, Viral/immunology , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/genetics , Male , Female , COVID-19/prevention & control , COVID-19/immunology , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Young Adult , Middle Aged , Adolescent , Vaccines, Synthetic/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/adverse effects
2.
Antimicrob Agents Chemother ; 68(4): e0127323, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38376227

ABSTRACT

The objective of this study was to evaluate the safety, tolerability, pharmacokinetics (PK), and immunogenicity of VIR-2482 in healthy adult subjects. A phase 1, first-in-human, randomized, double-blind, placebo-controlled dose-escalation study was conducted. One hundred participants were allocated to four cohorts (60 mg, 300 mg, 1,200 mg, and 1,800 mg). In each cohort, participants were randomized in a 4:1 ratio (active:placebo) to receive either VIR-2482 or volume-matched placebo by gluteal intramuscular injection. Participants remained at the investigative site under observation for 48 h, and adverse events (AEs) were collected for 56 days. PK and immunogenicity were measured up to 52 weeks post-dose. VIR-2482 was well tolerated at all doses studied. The overall incidence of AEs was comparable between VIR-2482 (68.8%) and placebo (85.0%). Nineteen VIR-2482 (23.8%) and six placebo (30.0%) recipients had Grade 1 or 2 AEs that were considered to be related to the study intervention. There were no treatment-related serious AEs. Injection-site reactions (ISRs) were reported in six (7.5%) VIR-2482 recipients, while no such reactions were reported among the placebo recipients. All ISRs were Grade 1, and there was no relationship with the dose. Median VIR-2482 serum elimination half-life ranged from 56.7 to 70.6 days across cohorts. The serum area under the curve and Cmax were dose-proportional. Nasopharyngeal VIR-2482 concentrations were approximately 2%-5% of serum levels and were less than dose-proportional. The incidence of immunogenicity across all cohorts was 1.3%. Overall, the safety, tolerability, and pharmacokinetic profile of VIR-2482 at doses up to 1,800 mg supported its further investigation as a long-acting antibody for the prevention of influenza A illness. This study has been registered at ClinicalTrials.gov under identifier NCT04033406.


Subject(s)
Antibodies, Monoclonal , Influenza, Human , Adult , Humans , Antibodies, Monoclonal/adverse effects , Influenza, Human/drug therapy , Influenza, Human/prevention & control , Healthy Volunteers , Double-Blind Method
3.
Inorg Chem ; 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39120873

ABSTRACT

The preassociation of reactants in a photoinitiated redox reaction through the use of noncovalent interactions can have a significant impact on excited state reactivity. As these noncovalent interactions render some stabilization to the associated species, they impact the kinetics and thermodynamics of photoinitiated electron transfer. Reported herein is a novel iridium(III) photocatalyst, equipped with an anion-sensitive, amide-substituted bipyridine ligand, and its reactivity with the halides (X = I-, Br-, Cl-) in acetonitrile and dichloromethane. A noteworthy periodic trend was observed, where the size and electron affinity dramatically altered the observed photoredox behavior. The binding affinity for the halides increased with decreasing ionic radius (Keq ∼103 to >106) in a polar medium but association was stoichiometric for each halide in a nonpolar medium. Evidence for the static quenching of iodide and bromide is presented while dynamic quenching was observed with all halides. These results highlight how the photophysics of halide adducts and the thermodynamics of intra-ionic photo-oxidation are impacted as a consequence of preassociation of a quencher through hydrogen bonding.

4.
J Stroke Cerebrovasc Dis ; 33(9): 107888, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39067658

ABSTRACT

BACKGROUND: Evaluation and hospitalization rates after a transient ischemic attack (TIA)-like presentation vary widely in clinical practice. This study aimed to examine variations in care settings at initial TIA diagnosis in the United States. METHODS: We retrospectively analyzed an adult cohort with a first TIA principal diagnosis between January 1, 2015, and December 31, 2019, from TriNetX Diamond Network. Care settings at TIA diagnosis were defined as hospital care (including inpatient services and observation unit care without admission) and outpatient care (including any outpatient or emergency department visits). We estimated the distribution of care settings at TIA diagnosis and examined the associations of the hospital care setting with baseline age, sex, race, ethnicity, region, and stroke history. RESULTS: Among the 554,315 included patients, 38.8% received hospital care at their initial TIA diagnosis. A higher percentage of hospital care was observed in the age group of 50-64 years (40.3%), Black (46.0%), Hispanic (41.2%), South (40.9%), and Midwest (43.0%) Regions, and with a history of stroke (39.6%). Multivariable logistic regression consistently showed patients who were aged 50-64 years (Odds Ratio=1.09, 95% CI: [1.07, 1.11]), Black (1.28, [1.24, 1.32]), Hispanic (1.13, [1.09, 1.18]), from South (1.20, [1.18, 1.22]) and Midwest Region (1.33, [1.30, 1.35]), and had a history of stroke (1.02, [1.00, 1.04]) to more likely receive hospital care. CONCLUSIONS: Although there are TIA care disparities based on demographics, most patients with initial TIA received acute care in outpatient settings. It is imperative to ensure primary providers can risk-stratify TIA patients and provide rapid and proper management.

5.
J Infect Dis ; 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37970668

ABSTRACT

BACKGROUND: Mutations present in emerging SARS-CoV-2 variants permit evasion of neutralization with prototype vaccines. A novel Omicron BA.1 subvariant-specific vaccine (NVX-CoV2515) was tested alone, or as a bivalent preparation in combination with the prototype vaccine (NVX-CoV2373), to assess antibody responses to SARS-CoV-2. METHODS: Participants aged 18 to 64 years immunized with 3 doses of prototype mRNA vaccines were randomized 1:1:1 to receive a single dose of NVX-CoV2515, NVX-CoV2373, or bivalent mixture in a phase 3 study investigating heterologous boosting with SARS-CoV-2 recombinant spike protein vaccines. Immunogenicity was measured 14 and 28 days after vaccination for the SARS-CoV-2 Omicron BA.1 sublineage and ancestral strain. Safety profiles of vaccines were assessed. RESULTS: Of participants who received trial vaccine (N = 829), those administered NVX-CoV2515 (n = 286) demonstrated superior neutralizing antibody response to BA.1 versus NVX-CoV2373 (n = 274) at Day 14 (geometric mean titer ratio [95% CI]: 1.6 [1.33, 2.03]). Seroresponse rates [n/N; 95% CI] were 73.4% [91/124; 64.7, 80.9] for NVX-CoV2515 versus 50.9% [59/116; 41.4, 60.3] for NVX-CoV2373. All formulations were similarly well-tolerated. CONCLUSIONS: NVX-CoV2515 elicited a superior neutralizing antibody response against the Omicron BA.1 subvariant compared with NVX-CoV2373 when administered as a fourth dose. Safety data were consistent with the established safety profile of NVX-CoV2373.

6.
J Am Chem Soc ; 145(37): 20158-20162, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37683290

ABSTRACT

We report the electron transfer (ET) self-exchange rate constants (k11) for a pair of CuII/I complexes utilizing dpaR (dpa = dipicolylaniline, R = OMe, SMe) ligands assessed by NMR line broadening experiments. These ligands afford copper complexes that are conformationally dynamic in one oxidation state. With R = OMe, the CuI complex is dynamic, while with R = SMe, the CuII complex is dynamic. Both complexes exhibit unexpectedly large k11 values of 2.48(6) × 105 and 2.21(9) × 106 M-1 s-1 for [CuCl(dpaOMe)]+/0 and [CuCl(dpaSMe)]+/0, respectively. Among the fastest reported molecular copper coordination complexes to date, that of [CuCl(dpaSMe)]+/0 exceeds all others by an order of magnitude and compares only with those observed in type 1 blue copper proteins. The dynamicity of these complexes establishes pre-steady-state conformational equilibria that minimize the inner-sphere reorganization energies to 0.71 and 0.62 eV for R = OMe and SMe, respectively. In contrast to the emphasis on rigidity in the formulation of entatic states applied to blue copper proteins, the success of these two systems highlights the relevance of conformational dynamicity in mediating rapid ET.

7.
N Engl J Med ; 383(24): 2320-2332, 2020 12 10.
Article in English | MEDLINE | ID: mdl-32877576

ABSTRACT

BACKGROUND: NVX-CoV2373 is a recombinant severe acute respiratory syndrome coronavirus 2 (rSARS-CoV-2) nanoparticle vaccine composed of trimeric full-length SARS-CoV-2 spike glycoproteins and Matrix-M1 adjuvant. METHODS: We initiated a randomized, placebo-controlled, phase 1-2 trial to evaluate the safety and immunogenicity of the rSARS-CoV-2 vaccine (in 5-µg and 25-µg doses, with or without Matrix-M1 adjuvant, and with observers unaware of trial-group assignments) in 131 healthy adults. In phase 1, vaccination comprised two intramuscular injections, 21 days apart. The primary outcomes were reactogenicity; laboratory values (serum chemistry and hematology), according to Food and Drug Administration toxicity scoring, to assess safety; and IgG anti-spike protein response (in enzyme-linked immunosorbent assay [ELISA] units). Secondary outcomes included unsolicited adverse events, wild-type virus neutralization (microneutralization assay), and T-cell responses (cytokine staining). IgG and microneutralization assay results were compared with 32 (IgG) and 29 (neutralization) convalescent serum samples from patients with Covid-19, most of whom were symptomatic. We performed a primary analysis at day 35. RESULTS: After randomization, 83 participants were assigned to receive the vaccine with adjuvant and 25 without adjuvant, and 23 participants were assigned to receive placebo. No serious adverse events were noted. Reactogenicity was absent or mild in the majority of participants, more common with adjuvant, and of short duration (mean, ≤2 days). One participant had mild fever that lasted 1 day. Unsolicited adverse events were mild in most participants; there were no severe adverse events. The addition of adjuvant resulted in enhanced immune responses, was antigen dose-sparing, and induced a T helper 1 (Th1) response. The two-dose 5-µg adjuvanted regimen induced geometric mean anti-spike IgG (63,160 ELISA units) and neutralization (3906) responses that exceeded geometric mean responses in convalescent serum from mostly symptomatic Covid-19 patients (8344 and 983, respectively). CONCLUSIONS: At 35 days, NVX-CoV2373 appeared to be safe, and it elicited immune responses that exceeded levels in Covid-19 convalescent serum. The Matrix-M1 adjuvant induced CD4+ T-cell responses that were biased toward a Th1 phenotype. (Funded by the Coalition for Epidemic Preparedness Innovations; ClinicalTrials.gov number, NCT04368988).


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Adjuvants, Immunologic/administration & dosage , Adolescent , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/adverse effects , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunization Schedule , Immunogenicity, Vaccine , Immunoglobulin G/immunology , Male , Middle Aged , Nanoparticles , Pandemics , Saponins , Th1 Cells/immunology , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Young Adult
8.
Opt Express ; 31(20): 33582-33595, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859136

ABSTRACT

Magnetic field imaging is a valuable resource for signal source localization and characterization. This work reports an optically pumped magnetometer (OPM) based on the free-induction-decay (FID) protocol, that implements microfabricated cesium (Cs) vapor cell technology to visualize the magnetic field distributions resulting from various magnetic sources placed close to the cell. The slow diffusion of Cs atoms in the presence of a nitrogen (N2) buffer gas enables spatially independent measurements to be made within the same vapor cell by translating a 175 µm diameter probe beam over the sensing area. For example, the OPM was used to record temporal and spatial information to reconstruct magnetic field distributions in one and two dimensions. The optimal magnetometer sensitivity was estimated to be 0.43 pT/H z within a Nyquist limited bandwidth of 500 Hz. Furthermore, the sensor's dynamic range exceeds the Earth's field of approximately 50 µT, which provides a framework for magnetic field imaging in unshielded environments.

9.
Opt Express ; 31(24): 40871-40880, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-38041377

ABSTRACT

Grating magneto-optical traps are an enabling quantum technology for portable metrological devices with ultracold atoms. However, beam diffraction efficiency and angle are affected by wavelength, creating a single-optic design challenge for laser cooling in two stages at two distinct wavelengths - as commonly used for loading, e.g., Sr or Yb atoms into optical lattice or tweezer clocks. Here, we optically characterize a wide variety of binary gratings at different wavelengths to find a simple empirical fit to experimental grating diffraction efficiency data in terms of dimensionless etch depth and period for various duty cycles. The model avoids complex 3D light-grating surface calculations, yet still yields results accurate to a few percent across a broad range of parameters. Gratings optimized for two (or more) wavelengths can now be designed in an informed manner suitable for a wide class of atomic species enabling advanced quantum technologies.

10.
Opt Lett ; 48(1): 37-40, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36563364

ABSTRACT

We demonstrate the integration of micro-electro-mechanical-systems (MEMS) scanning mirrors as active elements for the local optical pumping of ultra-cold atoms in a magneto-optical trap. A pair of MEMS mirrors steer a focused resonant beam through a cloud of trapped atoms shelved in the F = 1 ground-state of 87Rb for spatially selective fluorescence of the atom cloud. Two-dimensional control is demonstrated by forming geometrical patterns along the imaging axis of the cold atom ensemble. Such control of the atomic ensemble with a microfabricated mirror pair could find applications in single atom selection, local optical pumping, and arbitrary cloud shaping. This approach has significant potential for miniaturization and in creating portable control systems for quantum optic experiments.

11.
Value Health ; 26(6): 796-801, 2023 06.
Article in English | MEDLINE | ID: mdl-36436793

ABSTRACT

OBJECTIVES: The drug overdose crisis with shifting patterns from primarily opioid to polysubstance uses and COVID-19 infections are 2 concurrent public health crises in the United States, affecting the population of sizes in different magnitudes (approximately < 10 million for substance use disorder [SUD] and drug overdoses vs 80 million for COVID-19 within 2 years of the pandemic). Our objective is to compare the relative scale of disease burden for the 2 crises within a common framework, which could help inform policy makers with resource allocation and prioritization strategies. METHODS: We calculated disability-adjusted life-years (DALYs) for SUD (including opioids and stimulants) and COVID-19 infections, respectively. We collected estimates for SUD prevalence, overdose deaths, COVID-19 cases and deaths, disability weights, and life expectancy from multiple publicly available sources. We then compared age distributions of estimated DALYs. RESULTS: We estimated a total burden of 13.83 million DALYs for SUD and drug overdoses and 15.03 million DALYs for COVID-19 in 2 years since March 2020. COVID-19 burden was dominated by the fatal burden (> 95% of total DALYs), whereas SUD burden was attributed to both fatal (53%) and nonfatal burdens (47%). The highest disease burden was among individuals aged 30 to 39 years for SUD (27%) and 50 to 64 years for COVID-19 (31%). CONCLUSIONS: Despite the smaller size of the affected population, SUD and drug overdoses resulted in comparable disease burden with the COVID-19 pandemic. Additional resources supporting evidence-based interventions in prevention and treatment may be warranted to ameliorate SUD and drug overdoses during both the pandemic and postpandemic recovery.


Subject(s)
COVID-19 , Drug Overdose , Humans , United States/epidemiology , Disability-Adjusted Life Years , Pandemics , COVID-19/epidemiology , Quality-Adjusted Life Years , Drug Overdose/epidemiology
12.
Sex Health ; 20(6): 506-513, 2023 12.
Article in English | MEDLINE | ID: mdl-37599092

ABSTRACT

BACKGROUND: Australia, like many high-income countries, is experiencing a resurgence of infectious syphilis in pregnancy and congenital syphilis. Evaluations of public health notifications and clinical records suggest that healthcare systems may not be providing optimal care to women and their neonates. This study aims to explore the barriers to optimal management of syphilis in pregnancy and congenital syphilis to identify key areas for improvement. METHODS: Between 2021 and 2022, 34 healthcare workers (HCW) practicing in south-east Queensland (SEQ) Australia were recruited to complete semi-structured interviews regarding their perceptions towards management of syphilis in pregnancy and congenital syphilis. Interviews were analysed thematically. RESULTS: Thematic analysis identified four themes related to the management of syphilis in pregnancy. These included poor communication between disciplines, services, and teams from delivery through to management and post-delivery, lack of formal internal and external referral pathways, unclear and often complex maternal and congenital syphilis management procedures, and limited HCW knowledge of infectious syphilis in pregnancy and congenital syphilis. CONCLUSION: As congenital syphilis numbers continue to rise in SEQ, it is imperative that healthcare systems and HCWs identify and address gaps in the provision of health care.


Subject(s)
Pregnancy Complications, Infectious , Syphilis, Congenital , Syphilis , Pregnancy , Infant, Newborn , Female , Humans , Syphilis/diagnosis , Syphilis/epidemiology , Syphilis, Congenital/epidemiology , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/therapy , Queensland/epidemiology , Australia
13.
Sex Health ; 20(4): 330-338, 2023 08.
Article in English | MEDLINE | ID: mdl-37245957

ABSTRACT

BACKGROUND: Increasing rates of syphilis in pregnancy (SiP) in Australia and other high-income countries, has led to the resurgence of congenital syphilis. Suboptimal syphilis screening during pregnancy has been identified as a key contributing factor. METHODS: This study aimed to explore, from the perspective of multidisciplinary healthcare providers (HCPs), the barriers to optimal screening during the antenatal care (ANC) pathway. Semi-structured interviews conducted with 34 HCPs across multiple disciplines practising in south-east Queensland (SEQ) were analysed through a process of reflexive thematic analysis. RESULTS: Barriers were found to occur at the system level of ANC, through difficulties in patient engagement in care, limitations in the current model of health care delivery and limitations in the communication pathways across health care disciplines; and at the individual HCP level, through HCP knowledge and awareness of epidemiological changes in syphilis in SEQ, and adequately assessing patient risk. CONCLUSION: It is imperative that the healthcare systems and HCPs involved in ANC address these barriers to improve screening in order to optimise management of women and prevent congenital syphilis cases in SEQ.


Subject(s)
Pregnancy Complications, Infectious , Syphilis, Congenital , Syphilis , Pregnancy , Female , Humans , Syphilis/diagnosis , Syphilis/epidemiology , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , Queensland/epidemiology , Health Personnel
14.
Sensors (Basel) ; 23(8)2023 Apr 15.
Article in English | MEDLINE | ID: mdl-37112348

ABSTRACT

Machine learning (ML) is an effective tool to interrogate complex systems to find optimal parameters more efficiently than through manual methods. This efficiency is particularly important for systems with complex dynamics between multiple parameters and a subsequent high number of parameter configurations, where an exhaustive optimisation search would be impractical. Here we present a number of automated machine learning strategies utilised for optimisation of a single-beam caesium (Cs) spin exchange relaxation free (SERF) optically pumped magnetometer (OPM). The sensitivity of the OPM (T/Hz), is optimised through direct measurement of the noise floor, and indirectly through measurement of the on-resonance demodulated gradient (mV/nT) of the zero-field resonance. Both methods provide a viable strategy for the optimisation of sensitivity through effective control of the OPM's operational parameters. Ultimately, this machine learning approach increased the optimal sensitivity from 500 fT/Hz to <109fT/Hz. The flexibility and efficiency of the ML approaches can be utilised to benchmark SERF OPM sensor hardware improvements, such as cell geometry, alkali species and sensor topologies.

15.
J Infect Dis ; 225(6): 1062-1069, 2022 03 15.
Article in English | MEDLINE | ID: mdl-32479608

ABSTRACT

BACKGROUND: Interventions that effectively target Plasmodium vivax are critical for the future control and elimination of malaria. We conducted a P. vivax volunteer infection study to characterize the antimalarial activity of artefenomel, a new drug candidate. METHODS: Eight healthy, malaria-naive participants were intravenously inoculated with blood-stage P. vivax and subsequently received a single oral 200-mg dose of artefenomel. Blood samples were collected to monitor the development and clearance of parasitemia, and plasma artefenomel concentration. Mosquito feeding assays were conducted before artefenomel dosing to investigate parasite transmissibility. RESULTS: Initial parasite clearance occurred in all participants after artefenomel administration (log10 parasite reduction ratio over 48 hours, 1.67; parasite clearance half-life, 8.67 hours). Recrudescence occurred in 7 participants 11-14 days after dosing. A minimum inhibitory concentration of 0.62 ng/mL and minimum parasiticidal concentration that achieves 90% of maximum effect of 0.83 ng/mL were estimated, and a single 300-mg dose was predicted to clear 109 parasites per milliliter with 95% certainty. Gametocytemia developed in all participants and was cleared 4-8 days after dosing. At peak gametocytemia, 75% of participants were infectious to mosquitoes. CONCLUSIONS: The in vivo antimalarial activity of artefenomel supports its further clinical development as a treatment for P. vivax malaria. CLINICAL TRIALS REGISTRATION: NCT02573857.


Subject(s)
Antimalarials , Culicidae , Folic Acid Antagonists , Malaria, Falciparum , Malaria, Vivax , Parasites , Adamantane/analogs & derivatives , Animals , Antimalarials/pharmacology , Antimalarials/therapeutic use , Folic Acid Antagonists/pharmacology , Humans , Malaria, Falciparum/parasitology , Malaria, Vivax/drug therapy , Peroxides , Plasmodium falciparum , Plasmodium vivax
16.
J Am Chem Soc ; 144(27): 12116-12126, 2022 07 13.
Article in English | MEDLINE | ID: mdl-35762527

ABSTRACT

The continued development of solar energy as a renewable resource necessitates new approaches to sustaining photodriven charge separation (CS). We present a bioinspired approach in which photoinduced conformational rearrangements at a ligand are translated into changes in coordination geometry and environment about a bound metal ion. Taking advantage of the differential coordination properties of CuI and CuII, these dynamics aim to facilitate intramolecular electron transfer (ET) from CuI to the ligand to create a CS state. The synthesis and photophysical characterization of CuCl(dpaaR) (dpaa = dipicolylaminoacetophenone, with R = H and OMe) are presented. These ligands incorporate a fluorophore that gives rise to a twisted intramolecular charge transfer (TICT) excited state. Excited-state ligand twisting provides a tetragonal coordination geometry capable of capturing CuII when an internal ortho-OMe binding site is present. NMR, IR, electron paramagnetic resonance (EPR), and optical spectroscopies, X-ray diffraction, and electrochemical methods establish the ground-state properties of these CuI and CuII complexes. The photophysical dynamics of the CuI complexes are explored by time-resolved photoluminescence and optical transient absorption spectroscopies. Relative to control complexes lacking a TICT-active ligand, the lifetimes of CS states are enhanced ∼1000-fold. Further, the presence of the ortho-OMe substituent greatly enhances the lifetime of the TICT* state and biases the coordination environment toward CuII. The presence of CuI decreases photoinduced degradation from 14 to <2% but does not result in significant quenching via ET. Factors affecting CS in these systems are discussed, laying the groundwork for our strategy toward solar energy conversion.


Subject(s)
Coordination Complexes , Coordination Complexes/chemistry , Copper/chemistry , Electron Spin Resonance Spectroscopy , Ligands , Molecular Conformation
17.
Antimicrob Agents Chemother ; 66(1): e0158421, 2022 01 18.
Article in English | MEDLINE | ID: mdl-34694880

ABSTRACT

Despite repeated malaria infection, individuals living in areas where malaria is endemic remain vulnerable to reinfection. The Janus kinase (JAK1/2) inhibitor ruxolitinib could potentially disrupt the parasite-induced dysfunctional immune response when administered with antimalarial therapy. This randomized, single-blind, placebo-controlled, single-center phase 1 trial investigated the safety, tolerability, and pharmacokinetic and pharmacodynamic profile of ruxolitinib and the approved antimalarial artemether-lumefantrine in combination. Ruxolitinib pharmacodynamics were assessed by inhibition of phosphorylation of signal transducer and activator of transcription 3 (pSTAT3). Eight healthy male and female participants ages 18 to 55 years were randomized to either ruxolitinib (20 mg) (n = 6) or placebo (n = 2) administered 2 h after artemether-lumefantrine (80/480 mg) twice daily for 3 days. Mild adverse events occurred in six participants (four ruxolitinib; two placebo). The combination of artemether-lumefantrine and ruxolitinib was well tolerated, with adverse events and pharmacokinetics consistent with the known profiles of both drugs. The incidence of adverse events and artemether, dihydroartemisinin (the major active metabolite of artemether), and lumefantrine exposure were not affected by ruxolitinib coadministration. Ruxolitinib coadministration resulted in a 3-fold-greater pSTAT3 inhibition compared to placebo (geometric mean ratio = 3.01 [90% confidence interval = 2.14 to 4.24]), with a direct and predictable relationship between ruxolitinib plasma concentrations and %pSTAT3 inhibition. This study supports the investigation of the combination of artemether-lumefantrine and ruxolitinib in healthy volunteers infected with Plasmodium falciparum malaria. (This study has been registered at ClinicalTrials.gov under registration no. NCT04456634.).


Subject(s)
Antimalarials , Malaria, Falciparum , Adolescent , Adult , Antimalarials/adverse effects , Artemether/therapeutic use , Artemether, Lumefantrine Drug Combination/therapeutic use , Drug Combinations , Ethanolamines/therapeutic use , Female , Fluorenes/therapeutic use , Humans , Lumefantrine/therapeutic use , Malaria, Falciparum/drug therapy , Male , Middle Aged , Nitriles , Pyrazoles , Pyrimidines , Single-Blind Method , Young Adult
18.
BMC Nephrol ; 23(1): 287, 2022 08 18.
Article in English | MEDLINE | ID: mdl-35982411

ABSTRACT

BACKGROUND: The electronic health record (EHR), utilized to apply statistical methodology, assists provider decision-making, including during the care of chronic kidney disease (CKD) patients. When estimated glomerular filtration (eGFR) decreases, the rate of that change adds meaning to a patient's single eGFR and may represent severity of renal injury. Since the cumulative sum chart technique (CUSUM), often used in quality control and surveillance, continuously checks for change in a series of measurements, we selected this statistical tool to detect clinically relevant eGFR decreases and developed CUSUMGFR. METHODS: In a retrospective analysis we applied an age adjusted CUSUMGFR, to signal identification of eventual ESKD patients prior to diagnosis date. When the patient signaled by reaching a specified threshold value, days from CUSUM signal date to ESKD diagnosis date (earliness days) were measured, along with the corresponding eGFR measurement at the signal. RESULTS: Signaling occurred by CUSUMGFR on average 791 days (se = 12 days) prior to ESKD diagnosis date with sensitivity = 0.897, specificity = 0.877, and accuracy = .878. Mean days prior to ESKD diagnosis were significantly greater in Black patients (905 days) and patients with hypertension (852 days), diabetes (940 days), cardiovascular disease (1027 days), and hypercholesterolemia (971 days). Sensitivity and specificity did not vary by sociodemographic and clinical risk factors. CONCLUSIONS: CUSUMGFR correctly identified 30.6% of CKD patients destined for ESKD when eGFR was > 60 ml/min/1.73 m2 and signaled 12.3% of patients that did not go on to ESKD (though almost all went on to later-stage CKD). If utilized in an EHR, signaling patients could focus providers' efforts to slow or prevent progression to later stage CKD and ESKD.


Subject(s)
Kidney Failure, Chronic , Renal Insufficiency, Chronic , Disease Progression , Glomerular Filtration Rate , Humans , Kidney , Kidney Failure, Chronic/epidemiology , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Retrospective Studies
19.
Aust N Z J Obstet Gynaecol ; 62(1): 91-97, 2022 02.
Article in English | MEDLINE | ID: mdl-34463955

ABSTRACT

BACKGROUND: Syphilis in pregnancy and congenital syphilis (CS) are increasing in Australia. Prevention of adverse outcomes requires adherence to management guidelines. AIMS: The aim is to evaluate the management of syphilis in pregnant women and their newborns. MATERIALS AND METHODS: A retrospective study of public health notifications, clinical records and testing results of women with positive syphilis serology in pregnancy requiring treatment from 2016 to 2018 inclusive across South-East Queensland was conducted. Management was described and compared with contemporary guidelines from the Australasian Society of Infectious Diseases, the Communicable Diseases Network Australia and the United States Centers for Disease Control and Prevention. RESULTS: Of 30 women identified, 22 (73%) had management consistent with the guidelines (stage-appropriate penicillin regimen, appropriate dosing interval and treatment completed greater than 30 days before delivery). Only 14 (47%) women had documentation of partner testing and/or treatment. Of 26 mother-infant pairs with complete data, 16 (62%) had investigations at delivery consistent with recommendations (parallel maternal-infant rapid plasma reagin, infant syphilis immunoglobulin M, placental histopathology +/- syphilis polymerase chain reaction and infant clinical examination). One infant met the criteria for confirmed CS. Five infants received penicillin therapy. Only seven (27%) infants had serological monitoring after discharge. CONCLUSIONS: Management can be optimised with timely maternal testing and treatment, comprehensive partner screening and treatment, strict adherence to seven-day penicillin dosing for late latent syphilis and thorough maternal and infant testing after treatment and delivery. If maternal treatment was inadequate in pregnancy, consideration needs to be given to close evaluation and empiric treatment of the infant.


Subject(s)
Pregnancy Complications, Infectious , Syphilis, Congenital , Syphilis , Female , Humans , Infant , Infant, Newborn , Placenta , Pregnancy , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/drug therapy , Queensland , Retrospective Studies , Syphilis/diagnosis , Syphilis/drug therapy , Syphilis, Congenital/diagnosis , Syphilis, Congenital/drug therapy , Syphilis, Congenital/prevention & control
20.
Article in English | MEDLINE | ID: mdl-33199389

ABSTRACT

The spiroindolone cipargamin, a new antimalarial compound that inhibits Plasmodium ATP4, is currently in clinical development. This study aimed to characterize the antimalarial activity of cipargamin in healthy volunteers experimentally infected with blood-stage Plasmodium falciparum Eight subjects were intravenously inoculated with parasite-infected erythrocytes and received a single oral dose of 10 mg cipargamin 7 days later. Blood samples were collected to monitor the development and clearance of parasitemia and plasma cipargamin concentrations. Parasite regrowth was treated with piperaquine monotherapy to clear asexual parasites, while allowing gametocyte transmissibility to mosquitoes to be investigated. An initial rapid decrease in parasitemia occurred in all participants following cipargamin dosing, with a parasite clearance half-life of 3.99 h. As anticipated from the dose selected, parasite regrowth occurred in all 8 subjects 3 to 8 days after dosing and allowed the pharmacokinetic/pharmacodynamic relationship to be determined. Based on the limited data from the single subtherapeutic dose cohort, a MIC of 11.6 ng/ml and minimum parasiticidal concentration that achieves 90% of maximum effect of 23.5 ng/ml were estimated, and a single 95-mg dose (95% confidence interval [CI], 50 to 270) was predicted to clear 109 parasites/ml. Low gametocyte densities were detected in all subjects following piperaquine treatment, which did not transmit to mosquitoes. Serious adverse liver function changes were observed in three subjects, which led to premature study termination. The antimalarial activity characterized in this study supports the further clinical development of cipargamin as a new treatment for P. falciparum malaria, although the hepatic safety profile of the compound warrants further evaluation. (This study has been registered at ClinicalTrials.gov under identifier NCT02543086.).


Subject(s)
Antimalarials , Malaria, Falciparum , Animals , Antimalarials/pharmacology , Antimalarials/therapeutic use , Healthy Volunteers , Humans , Indoles , Malaria, Falciparum/drug therapy , Plasmodium falciparum , Spiro Compounds
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