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1.
Nature ; 592(7852): 35-42, 2021 04.
Article in English | MEDLINE | ID: mdl-33790445

ABSTRACT

The photon-the quantum excitation of the electromagnetic field-is massless but carries momentum. A photon can therefore exert a force on an object upon collision1. Slowing the translational motion of atoms and ions by application of such a force2,3, known as laser cooling, was first demonstrated 40 years ago4,5. It revolutionized atomic physics over the following decades6-8, and it is now a workhorse in many fields, including studies on quantum degenerate gases, quantum information, atomic clocks and tests of fundamental physics. However, this technique has not yet been applied to antimatter. Here we demonstrate laser cooling of antihydrogen9, the antimatter atom consisting of an antiproton and a positron. By exciting the 1S-2P transition in antihydrogen with pulsed, narrow-linewidth, Lyman-α laser radiation10,11, we Doppler-cool a sample of magnetically trapped antihydrogen. Although we apply laser cooling in only one dimension, the trap couples the longitudinal and transverse motions of the anti-atoms, leading to cooling in all three dimensions. We observe a reduction in the median transverse energy by more than an order of magnitude-with a substantial fraction of the anti-atoms attaining submicroelectronvolt transverse kinetic energies. We also report the observation of the laser-driven 1S-2S transition in samples of laser-cooled antihydrogen atoms. The observed spectral line is approximately four times narrower than that obtained without laser cooling. The demonstration of laser cooling and its immediate application has far-reaching implications for antimatter studies. A more localized, denser and colder sample of antihydrogen will drastically improve spectroscopic11-13 and gravitational14 studies of antihydrogen in ongoing experiments. Furthermore, the demonstrated ability to manipulate the motion of antimatter atoms by laser light will potentially provide ground-breaking opportunities for future experiments, such as anti-atomic fountains, anti-atom interferometry and the creation of antimatter molecules.

2.
Nature ; 561(7722): 211-215, 2018 09.
Article in English | MEDLINE | ID: mdl-30135588

ABSTRACT

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum1,2. The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now know governs the world at the atomic scale. Since then, studies involving the Lyman-α line-the 1S-2P transition at a wavelength of 121.6 nanometres-have played an important part in physics and astronomy, as one of the most fundamental atomic transitions in the Universe. For example, this transition has long been used by astronomers studying the intergalactic medium and testing cosmological models via the so-called 'Lyman-α forest'3 of absorption lines at different redshifts. Here we report the observation of the Lyman-α transition in the antihydrogen atom, the antimatter counterpart of hydrogen. Using narrow-line-width, nanosecond-pulsed laser radiation, the 1S-2P transition was excited in magnetically trapped antihydrogen. The transition frequency at a field of 1.033 tesla was determined to be 2,466,051.7 ± 0.12 gigahertz (1σ uncertainty) and agrees with the prediction for hydrogen to a precision of 5 × 10-8. Comparisons of the properties of antihydrogen with those of its well-studied matter equivalent allow precision tests of fundamental symmetries between matter and antimatter. Alongside the ground-state hyperfine4,5 and 1S-2S transitions6,7 recently observed in antihydrogen, the Lyman-α transition will permit laser cooling of antihydrogen8,9, thus providing a cold and dense sample of anti-atoms for precision spectroscopy and gravity measurements10. In addition to the observation of this fundamental transition, this work represents both a decisive technological step towards laser cooling of antihydrogen, and the extension of antimatter spectroscopy to quantum states possessing orbital angular momentum.

4.
Nature ; 557(7703): 71-75, 2018 05.
Article in English | MEDLINE | ID: mdl-29618820

ABSTRACT

In 1928, Dirac published an equation 1 that combined quantum mechanics and special relativity. Negative-energy solutions to this equation, rather than being unphysical as initially thought, represented a class of hitherto unobserved and unimagined particles-antimatter. The existence of particles of antimatter was confirmed with the discovery of the positron 2 (or anti-electron) by Anderson in 1932, but it is still unknown why matter, rather than antimatter, survived after the Big Bang. As a result, experimental studies of antimatter3-7, including tests of fundamental symmetries such as charge-parity and charge-parity-time, and searches for evidence of primordial antimatter, such as antihelium nuclei, have high priority in contemporary physics research. The fundamental role of the hydrogen atom in the evolution of the Universe and in the historical development of our understanding of quantum physics makes its antimatter counterpart-the antihydrogen atom-of particular interest. Current standard-model physics requires that hydrogen and antihydrogen have the same energy levels and spectral lines. The laser-driven 1S-2S transition was recently observed 8 in antihydrogen. Here we characterize one of the hyperfine components of this transition using magnetically trapped atoms of antihydrogen and compare it to model calculations for hydrogen in our apparatus. We find that the shape of the spectral line agrees very well with that expected for hydrogen and that the resonance frequency agrees with that in hydrogen to about 5 kilohertz out of 2.5 × 1015 hertz. This is consistent with charge-parity-time invariance at a relative precision of 2 × 10-12-two orders of magnitude more precise than the previous determination 8 -corresponding to an absolute energy sensitivity of 2 × 10-20 GeV.

5.
Clin Infect Dis ; 77(2): 229-236, 2023 07 26.
Article in English | MEDLINE | ID: mdl-36975097

ABSTRACT

BACKGROUND: In solid organ transplant (SOT) recipients, the primary vaccination series against Coronavirus Disease 2019 is 3 doses followed by boosters. We determined whether a fourth dose booster induced Omicron BA.4/5 neutralizing antibodies (nAbs) and T cells in a large multicenter cohort study. METHODS: Serum was collected 4-6 weeks post-third and post-fourth doses of messenger RNA vaccine in 222 SOT recipients. nAbs were measured using a pseudovirus neutralization assay that targeted the Omicron BA.4/5 spike protein. A subset underwent T-cell testing. RESULTS: The median age of the cohort was 63 years (interquartile range [IQR], 50-68) with 61.7% men. BA.4/5 nAb detection increased from 26.6% (59 of 222) post-third dose to 53.6% (119 of 222) post-fourth dose (P < .0001). In patients with breakthrough infection prior to the fourth dose (n = 27), nAbs were detected in 77.8% and median nAb titers were significantly higher compared with those with 4 vaccine doses alone (P < .0001). Factors associated with a low BA.4/5 neutralization response after the fourth dose were older age (odds ratio [OR], 0.96; 95% confidence interval [CI], .94-.99), mycophenolate use (OR, 0.39; 95% CI, .20-.77) and prednisone use (OR, 0.34; 95% CI, .18-.63), and vaccine type (OR, 0.72; 95% CI, .51-.99), while breakthrough infection prior to the fourth dose (OR, 3.6; 95% CI, 1.3-9.9) was associated with a greater nAb response. Polyfunctional BA.4/5-specific CD4+ T cells significantly increased after 4 doses and were identified in 76.9% of patients at a median frequency of 213/106 cells (IQR, 98-650). CONCLUSIONS: In summary, a booster significantly increases BA.4/5-specific neutralization and polyfunctional CD4+ T-cell responses, suggesting protection from severe disease even with new Omicron variants. However, SOT recipients who are older and on mycophenolate and prednisone need additional preventative strategies.


Subject(s)
COVID-19 , Organ Transplantation , Male , Humans , Middle Aged , Female , Cohort Studies , Prednisone , SARS-CoV-2 , Antibodies, Neutralizing , Breakthrough Infections , Immunosuppressive Agents/therapeutic use , RNA, Messenger , Transplant Recipients , mRNA Vaccines , Antibodies, Viral
6.
Nature ; 548(7665): 66-69, 2017 08 02.
Article in English | MEDLINE | ID: mdl-28770838

ABSTRACT

The observation of hyperfine structure in atomic hydrogen by Rabi and co-workers and the measurement of the zero-field ground-state splitting at the level of seven parts in 1013 are important achievements of mid-twentieth-century physics. The work that led to these achievements also provided the first evidence for the anomalous magnetic moment of the electron, inspired Schwinger's relativistic theory of quantum electrodynamics and gave rise to the hydrogen maser, which is a critical component of modern navigation, geo-positioning and very-long-baseline interferometry systems. Research at the Antiproton Decelerator at CERN by the ALPHA collaboration extends these enquiries into the antimatter sector. Recently, tools have been developed that enable studies of the hyperfine structure of antihydrogen-the antimatter counterpart of hydrogen. The goal of such studies is to search for any differences that might exist between this archetypal pair of atoms, and thereby to test the fundamental principles on which quantum field theory is constructed. Magnetic trapping of antihydrogen atoms provides a means of studying them by combining electromagnetic interaction with detection techniques that are unique to antimatter. Here we report the results of a microwave spectroscopy experiment in which we probe the response of antihydrogen over a controlled range of frequencies. The data reveal clear and distinct signatures of two allowed transitions, from which we obtain a direct, magnetic-field-independent measurement of the hyperfine splitting. From a set of trials involving 194 detected atoms, we determine a splitting of 1,420.4 ± 0.5 megahertz, consistent with expectations for atomic hydrogen at the level of four parts in 104. This observation of the detailed behaviour of a quantum transition in an atom of antihydrogen exemplifies tests of fundamental symmetries such as charge-parity-time in antimatter, and the techniques developed here will enable more-precise such tests.

7.
Nature ; 541(7638): 506-510, 2017 01 26.
Article in English | MEDLINE | ID: mdl-28005057

ABSTRACT

The spectrum of the hydrogen atom has played a central part in fundamental physics over the past 200 years. Historical examples of its importance include the wavelength measurements of absorption lines in the solar spectrum by Fraunhofer, the identification of transition lines by Balmer, Lyman and others, the empirical description of allowed wavelengths by Rydberg, the quantum model of Bohr, the capability of quantum electrodynamics to precisely predict transition frequencies, and modern measurements of the 1S-2S transition by Hänsch to a precision of a few parts in 1015. Recent technological advances have allowed us to focus on antihydrogen-the antimatter equivalent of hydrogen. The Standard Model predicts that there should have been equal amounts of matter and antimatter in the primordial Universe after the Big Bang, but today's Universe is observed to consist almost entirely of ordinary matter. This motivates the study of antimatter, to see if there is a small asymmetry in the laws of physics that govern the two types of matter. In particular, the CPT (charge conjugation, parity reversal and time reversal) theorem, a cornerstone of the Standard Model, requires that hydrogen and antihydrogen have the same spectrum. Here we report the observation of the 1S-2S transition in magnetically trapped atoms of antihydrogen. We determine that the frequency of the transition, which is driven by two photons from a laser at 243 nanometres, is consistent with that expected for hydrogen in the same environment. This laser excitation of a quantum state of an atom of antimatter represents the most precise measurement performed on an anti-atom. Our result is consistent with CPT invariance at a relative precision of about 2 × 10-10.

8.
Nature ; 531(7593): 210-4, 2016 Mar 10.
Article in English | MEDLINE | ID: mdl-26901870

ABSTRACT

The pseudogap is a partial gap in the electronic density of states that opens in the normal (non-superconducting) state of cuprate superconductors and whose origin is a long-standing puzzle. Its connection to the Mott insulator phase at low doping (hole concentration, p) remains ambiguous and its relation to the charge order that reconstructs the Fermi surface at intermediate doping is still unclear. Here we use measurements of the Hall coefficient in magnetic fields up to 88 tesla to show that Fermi-surface reconstruction by charge order in the cuprate YBa2Cu3Oy ends sharply at a critical doping p = 0.16 that is distinctly lower than the pseudogap critical point p* = 0.19 (ref. 11). This shows that the pseudogap and charge order are separate phenomena. We find that the change in carrier density n from n = 1 + p in the conventional metal at high doping (ref. 12) to n = p at low doping (ref. 13) starts at the pseudogap critical point. This shows that the pseudogap and the antiferromagnetic Mott insulator are linked.

9.
Nature ; 529(7586): 373-6, 2016 Jan 21.
Article in English | MEDLINE | ID: mdl-26791725

ABSTRACT

Antimatter continues to intrigue physicists because of its apparent absence in the observable Universe. Current theory requires that matter and antimatter appeared in equal quantities after the Big Bang, but the Standard Model of particle physics offers no quantitative explanation for the apparent disappearance of half the Universe. It has recently become possible to study trapped atoms of antihydrogen to search for possible, as yet unobserved, differences in the physical behaviour of matter and antimatter. Here we consider the charge neutrality of the antihydrogen atom. By applying stochastic acceleration to trapped antihydrogen atoms, we determine an experimental bound on the antihydrogen charge, Qe, of |Q| < 0.71 parts per billion (one standard deviation), in which e is the elementary charge. This bound is a factor of 20 less than that determined from the best previous measurement of the antihydrogen charge. The electrical charge of atoms and molecules of normal matter is known to be no greater than about 10(-21)e for a diverse range of species including H2, He and SF6. Charge-parity-time symmetry and quantum anomaly cancellation demand that the charge of antihydrogen be similarly small. Thus, our measurement constitutes an improved limit and a test of fundamental aspects of the Standard Model. If we assume charge superposition and use the best measured value of the antiproton charge, then we can place a new limit on the positron charge anomaly (the relative difference between the positron and elementary charge) of about one part per billion (one standard deviation), a 25-fold reduction compared to the current best measurement.

10.
J Virol ; 94(9)2020 04 16.
Article in English | MEDLINE | ID: mdl-32051267

ABSTRACT

Clinical trials investigating histone deacetylase inhibitors (HDACi) to reverse HIV-1 latency aim to expose reservoirs in antiretroviral (ARV)-treated individuals to clearance by immune effectors, yet have not driven measurable reductions in the frequencies of infected cells. We therefore investigated the effects of the class I-selective HDACi nanatinostat and romidepsin on various blocks to latency reversal and elimination, including viral splicing, antigen presentation, and CD8+ T cell function. In ex vivo CD4+ T cells from ARV-suppressed individuals, both HDACi significantly induced viral transcription, but not splicing nor supernatant HIV-1 RNA. In an HIV-1 latency model using autologous CD8+ T cell clones as biosensors of antigen presentation, neither HDACi-treated CD4+ T cell condition induced clone degranulation. Both HDACi also impaired the function of primary CD8+ T cells in viral inhibition assays, with nanatinostat causing less impairment. These findings suggest that spliced or cell-free HIV-1 RNAs are more indicative of antigen expression than unspliced HIV-RNAs and may help to explain the limited abilities of HDACi to generate CD8+ T cell targets in vivoIMPORTANCE Antiretroviral (ARV) drug regimens suppress HIV-1 replication but are unable to cure infection. This leaves people living with HIV-1 burdened by a lifelong commitment to expensive daily medication. Furthermore, it has become clear that ARV therapy does not fully restore health, leaving individuals at elevated risk for cardiovascular disease, certain types of cancers, and neurocognitive disorders, as well as leaving them exposed to stigma. Efforts are therefore under way to develop therapies capable of curing infection. A key focus of these efforts has been on a class of drugs called histone deacetylase inhibitors (HDACi), which have the potential of exposing hidden reservoirs of HIV-1 to elimination by the immune system. Unfortunately, clinical trial results with HDACi have thus far been disappointing. In the current study, we integrate a number of experimental approaches to build a model that provides insights into the limited activity of HDACi in clinical trials and offers direction for future approaches.


Subject(s)
Histone Deacetylase Inhibitors/pharmacology , Virus Latency/drug effects , Adult , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , Depsipeptides/pharmacology , Female , HIV Infections/immunology , HIV Seropositivity/drug therapy , HIV-1/metabolism , HIV-1/pathogenicity , HIV-1/physiology , Histone Deacetylases/metabolism , Humans , Male , Middle Aged , Primary Cell Culture , Virus Latency/physiology , Virus Replication/drug effects
11.
Sex Transm Infect ; 97(1): 18-26, 2021 02.
Article in English | MEDLINE | ID: mdl-32732335

ABSTRACT

OBJECTIVES: 'Undetectable equals Untransmittable' (U=U) is an empowering message that may enable people living with HIV (PLHIV) to reach and maintain undetectability. We estimated the percentage of PLHIV who ever discussed U=U with their main HIV care provider, and measured associations with health-related outcomes. Secondarily, we evaluated whether the impact of the U=U message varied between those who heard it from their healthcare provider (HCP) vs from elsewhere. METHODS: Data were from the 25-country 2019 Positive Perspectives Survey of PLHIV on treatment (n=2389). PLHIV were classified as having discussed U=U with their HCP if they indicated that their HCP had ever told them about U=U. Those who had not discussed U=U with their HCP but were nonetheless aware that 'My HIV medication prevents me from passing on HIV to others' were classified as being made aware of U=U from non-HCP sources. Multivariable logistic regression was used to measure associations between exposure to U=U messages and health outcomes. RESULTS: Overall, 66.5% reported ever discussing U=U with their HCP, from 38.0% (South Korea) to 87.3% (Switzerland). Prevalence was lowest among heterosexual men (57.6%) and PLHIV in Asia (51.3%). Compared with those unaware of U=U, those reporting U=U discussions with their HCP had lower odds of suboptimal adherence (AOR=0.59, 95% CI 0.44 to 0.78) and higher odds of self-reported viral suppression (AOR=2.34, 95% CI 1.72 to 3.20), optimal sexual health (AOR=1.48, 95% CI 1.14 to 1.92) and reporting they 'always shared' their HIV status (AOR=2.99, 95% CI 1.42 to 6.28). While exposure to U=U information from non-HCP sources was beneficial too, the observed associations were attenuated relative to those seen with reported discussions with HCPs. CONCLUSION: HCP discussion of U=U with PLHIV was associated with favourable health outcomes. However, missed opportunities exist since a third of PLHIV reported not having any U=U discussion with their HCP. U=U discussions with PLHIV should be considered as a standard of care in clinical guidelines.


Subject(s)
HIV Infections/prevention & control , HIV Infections/psychology , Health Communication , Health Knowledge, Attitudes, Practice , Cross-Sectional Studies , Female , Health Personnel , Humans , Internationality , Male , Middle Aged , Outcome Assessment, Health Care
12.
Stem Cells ; 38(2): 261-275, 2020 02.
Article in English | MEDLINE | ID: mdl-31721342

ABSTRACT

The tunica adventitia ensheathes arteries and veins and contains presumptive mesenchymal stem cells (MSCs) involved in vascular remodeling. We show here that a subset of human adventitial cells express the CD10/CALLA cell surface metalloprotease. Both CD10+ and CD10- adventitial cells displayed phenotypic features of MSCs when expanded in culture. However, CD10+ adventitial cells exhibited higher proliferation, clonogenic and osteogenic potentials in comparison to their CD10- counterparts. CD10+ adventitial cells increased expression of the cell cycle protein CCND2 via ERK1/2 signaling and osteoblastogenic gene expression via NF-κB signaling. CD10 expression was upregulated in adventitial cells through sonic hedgehog-mediated GLI1 signaling. These results suggest that CD10, which marks rapidly dividing cells in other normal and malignant cell lineages, plays a role in perivascular MSC function and cell fate specification. These findings also point to a role for CD10+ perivascular cells in vascular remodeling and calcification.


Subject(s)
Calcification, Physiologic/genetics , Neprilysin/metabolism , Stem Cells/metabolism , Adult , Aged , Aged, 80 and over , Cell Proliferation , Humans , Middle Aged
13.
Prev Med ; 142: 106372, 2021 01.
Article in English | MEDLINE | ID: mdl-33333128

ABSTRACT

While geographic differences in HIV burden are well documented, less is known about regional differences in perceived treatment needs. To fill this gap, the 2019 Positive Perspectives study of people living with HIV (PLHIV) was conducted in 25 countries across Northern America, Latin America, the Asian region, Europe (EU/Schengen countries), Russia, Australia, and South Africa (n = 2389). Overall mean duration of HIV was 10.1 (SD = 9.6) years. The perception that HIV had a negative impact on day-to-day life was lowest among participants from South Africa (14.0%[25/179]) and highest among participants from the Asian region (55.2%[127/230]). Most of the regional gap in the perception that HIV had a negative impact on daily life was explained by regional differences in medication-related unmet needs, stigma, demographic factors, and comorbidities. The percentage who felt they understood their treatment was highest among participants from Australia (87.5%[105/120]) and lowest among those from Russia (62.0%[93/150]), the Asian region (62.2%[143/230]), and South Africa (62.6%[112/179]). Among participants from Northern America, Europe, and Latin America, the treatment goals with the largest absolute increase in perceived importance, from time of starting treatment to time of survey among those diagnosed for ≥1 year, were minimizing the long term impact of antiretroviral treatment and keeping the number of medicines in their antiretroviral regimen at a minimum. Tailored approaches to care of PLHIV are needed as different regions have different disease burden and treatment needs. Equitable approaches to HIV care are needed across and within regions to ensure that patients' unmet needs and preferences are addressed to improve their overall wellbeing and health-related quality of life.


Subject(s)
HIV Infections , Quality of Life , Australia , Europe , HIV Infections/drug therapy , Humans , Latin America , North America , South Africa
14.
Int J Legal Med ; 135(6): 2221-2233, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34436656

ABSTRACT

The Illumina® MiSeq FGx™, in conjunction with the ForenSeq™ DNA Signature Prep kit, produces genotypes of the CODIS-required short tandem repeats and provides phenotype and biogeographical ancestry estimations via phenotype-informative and ancestry-informative markers, respectively. Although both markers have been validated for use in forensic biology, there is little data to determine the practical utility of these estimations to assist in identifying missing persons using decedent casework samples. The accuracy and utility of phenotypic and ancestral estimations were investigated for 300 samples received by the Los Angeles County Department of Medical Examiner-Coroner. piSNP genotypes were translated into hair and eye colors using the Forenseq™ Universal Analysis Software (UAS) on the MiSeq FGx™ and the HIrisPlex System, and statistical accuracy was evaluated in context with the reported decedent characteristics. Similarly, estimates of each decedent's biogeographical ancestry were compared to assess the efficacy of these markers to predict ancestry correctly. The average UAS and the HIrisPlex system prediction accuracy for brown and blue eyes were 95.3% and 96.2%, respectively. Intermediate eye color could not be predicted with high accuracy using either system. Other than the black hair phenotype reporting an accuracy that exceeded 90% using either system, hair color was also too variable to be predicted with high accuracy. The FROG-kb database distinguishes decedents adequately beyond the Asian, African, European, and Admixed American global ancestries provided by the MiSeq FGx™ UAS PCA plots. FROG-kb correctly identified Middle Eastern, Pacific Islander, Latin American, or Jewish ancestries with accuracies of 70.0%, 81.8%, 73.8%, and 86.7%, respectively.


Subject(s)
DNA Fingerprinting , Eye Color , Eye Color/genetics , Genotype , High-Throughput Nucleotide Sequencing , Humans , Phenotype , Polymorphism, Single Nucleotide , Reproducibility of Results
15.
Int J Legal Med ; 135(6): 2163-2173, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34245337

ABSTRACT

Chronological age estimation may offer valuable investigative leads in human identification cases. Bisulfite pyrosequencing analysis of single CpG sites on five genes (KLF14, ELOVL2, C1orf132, TRIM59, and FHL2) was performed on 264 postmortem blood samples from individuals aged 3 months to 93 years. The goals were to develop age prediction models based on the correlation between the methylation profile and chronological age and to assess the accuracy of the prediction. Linear regression between methylation levels and age at each CpG site revealed that the five markers show a statistically significant correlation with age. The methylation data from a training set of 160 postmortem blood samples were used to develop an age prediction model with a correlation coefficient of 0.65, explaining 73.1% of age variation, with a mean absolute deviation from the chronological age of 7.60 years. The accuracy of the model was evaluated with a test set of 72 samples producing a mean absolute deviation of 7.42 years. The training and test sets were also categorized by specific age groups to assess accuracy and deviation from chronological age. The data for both sets revealed a lower prediction potential as an individual increases in age, particularly for the age categories above 50 years.


Subject(s)
Body Remains , DNA Methylation , Aging/genetics , Child , CpG Islands , Forensic Genetics , Genetic Markers , Humans , Intracellular Signaling Peptides and Proteins , LIM-Homeodomain Proteins/genetics , Middle Aged , Muscle Proteins/genetics , Transcription Factors/genetics , Tripartite Motif Proteins
16.
AIDS Behav ; 25(3): 961-972, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33026574

ABSTRACT

To assess challenges with daily oral antiretroviral therapy (ART), we analyzed data for 2389 participants in the 2019 Positive Perspectives survey of people living with HIV in 25 countries. ART-related challenges reported included difficulty swallowing pills (33.1% [790/2389]); stress from daily dosing routine (33.3% [795/2389]); bad memories from daily intake of HIV medication (35.1%[839/2389]), and concern "that having to take pills every day means a greater chance of revealing my HIV status to others" (37.9% [906/2389]). Individuals who felt empowered by daily oral dosing ["taking my pill(s) every day reassures me that my HIV is being kept under control"] had 69% higher odds of optimal overall health (AOR 1.69, 95% CI 1.40-2.04). Conversely, odds of optimal overall health were lower among those who felt daily pill intake "limits my day-to-day life" (AOR 0.53, 95% CI 0.44-0.64). These findings show that there is need for increased flexibility of ART delivery to meet diverse patient needs.


Subject(s)
Anti-HIV Agents/administration & dosage , Antiretroviral Therapy, Highly Active/adverse effects , HIV Infections/drug therapy , HIV Infections/psychology , Medication Adherence/psychology , Quality of Life/psychology , Adult , Anti-HIV Agents/therapeutic use , Cross-Sectional Studies , Female , HIV Infections/epidemiology , Humans , Male , Middle Aged , Social Stigma
17.
Clin Infect Dis ; 70(11): 2241-2246, 2020 05 23.
Article in English | MEDLINE | ID: mdl-32445480

ABSTRACT

Persons living with human immunodeficiency virus (HIV) and others receiving antiretrovirals are at risk for medication errors during hospitalization and at transitions of care. These errors may result in adverse effects or viral resistance, limiting future treatment options. A range of interventions is described in the literature to decrease the occurrence or duration of medication errors, including review of electronic health records, clinical checklists at care transitions, and daily review of medication lists. To reduce the risk of medication-related errors, antiretroviral stewardship programs (ARVSPs) are needed to enhance patient safety. This call to action, endorsed by the Infectious Diseases Society of America, the HIV Medicine Association, and the American Academy of HIV Medicine, is modeled upon the success of antimicrobial stewardship programs now mandated by the Joint Commission. Herein, we propose definitions of ARVSPs, suggest resources for ARVSP leadership, and provide a summary of published, successful strategies for ARVSP that healthcare facilities may use to develop locally appropriate programs.


Subject(s)
Communicable Diseases , HIV Infections , Medicine , HIV Infections/drug therapy , Humans , Inpatients , Policy , United States
18.
Prev Med ; 139: 106182, 2020 10.
Article in English | MEDLINE | ID: mdl-32593732

ABSTRACT

Modern antiretroviral therapy (ART) has improved the lives of people living with HIV (PLHIV) but currently requires daily adherence. We assessed prevalence and correlates of suboptimal adherence, and measured associations with self-reported health outcomes. Data were from web-based surveys of confirmed HIV+ adults on antiretroviral treatment within 25 countries during 2019 (n = 2389). Suboptimal adherence was a report of ≥1 reason for missing ART ≥5 times within the past month. Multivariable logistic regression examined associations between suboptimal adherence and self-reported overall health and virologic suppression. Overall, 24.1% (575/2389) reported suboptimal adherence, from 10.0% (5/50) in Austria, to 62.0% (31/50) in China. The most common reasons for missing ART ≥5 times in the overall population were feeling depressed/overwhelmed (7.4%, 176/2389), trying to forget about HIV (7.0%, 168/2389), and work (6.1%, 145/2389). Correlates of suboptimal adherence included being heterosexual, <50 years old, ≤high school, having gastrointestinal treatment side effects, and privacy concerns. Odds of suboptimal overall health were 1.41 (95%CI, 1.11-1.80), 2.10 (95%CI, 1.65-2.68), and 2.55 (95%CI, 2.00-3.25) among those who reported the maximum number of times missed ART for any reason within the past month as 1, 2-4, or ≥5 times respectively, vs not missing at all. Odds of virologic nonsuppression were 1.80 (95%CI, 1.33-2.45), and 2.24 (95%CI, 1.66-3.02) for 2-4, or ≥5 times of missed ART respectively, vs not missing at all; missing for only 1 time was not significantly associated with virologic nonsuppression. Novel ART strategies designed to improve adherence along with interventions to empower PLHIV and support self-medication may improve health outcomes and quality of life.


Subject(s)
Anti-HIV Agents , HIV Infections , Adult , Anti-HIV Agents/therapeutic use , China/epidemiology , HIV Infections/drug therapy , HIV Infections/epidemiology , Humans , Medication Adherence , Middle Aged , Prevalence , Quality of Life
19.
Nature ; 511(7507): 61-4, 2014 Jul 03.
Article in English | MEDLINE | ID: mdl-24930767

ABSTRACT

An outstanding problem in the field of high-transition-temperature (high-Tc) superconductivity is the identification of the normal state out of which superconductivity emerges in the mysterious underdoped regime. The normal state uncomplicated by thermal fluctuations can be studied using applied magnetic fields that are sufficiently strong to suppress long-range superconductivity at low temperatures. Proposals in which the normal ground state is characterized by small Fermi surface pockets that exist in the absence of symmetry breaking have been superseded by models based on the existence of a superlattice that breaks the translational symmetry of the underlying lattice. Recently, a charge superlattice model that positions a small electron-like Fermi pocket in the vicinity of the nodes (where the superconducting gap is minimum) has been proposed as a replacement for the prevalent superlattice models that position the Fermi pocket in the vicinity of the pseudogap at the antinodes (where the superconducting gap is maximum). Although some ingredients of symmetry breaking have been recently revealed by crystallographic studies, their relevance to the electronic structure remains unresolved. Here we report angle-resolved quantum oscillation measurements in the underdoped copper oxide YBa2Cu3O6 + x. These measurements reveal a normal ground state comprising electron-like Fermi surface pockets located in the vicinity of the nodes, and also point to an underlying superlattice structure of low frequency and long wavelength with features in common with the charge order identified recently by complementary spectroscopic techniques.

20.
BMC Public Health ; 20(1): 509, 2020 Apr 16.
Article in English | MEDLINE | ID: mdl-32299421

ABSTRACT

BACKGROUND: Despite widely available access to HIV care in Washington, DC, inequities in HIV outcomes persist. We hypothesized that laboratory monitoring and virologic outcomes would not differ significantly based on insurance type. METHODS: We compared HIV monitoring with outcomes among people with HIV (PWH) with private (commercial payer) versus public (Medicare, Medicaid) insurance receiving care at community and hospital clinics. The DC Cohort follows over 8000 PWH from 14 clinics. We included those ≥18 years old enrolled between 2011 and 2015 with stable insurance. Outcomes included frequency of CD4 count and HIV RNA monitoring (> 2 lab measures/year, > 30 days apart) and durable viral suppression (VS; HIV RNA < 50 copies/mL at last visit and receiving antiretroviral therapy (ART) for ≥12 months). Multivariable logistic regression models examined impact of demographic and clinical factors. RESULTS: Among 3908 PWH, 67.9% were publicly-insured and 58.9% attended community clinics. Compared with privately insured participants, a higher proportion of publicly insured participants had the following characteristics: female sex, Black race, heterosexual, unemployed, and attending community clinics. Despite less lab monitoring, privately-insured PWH had greater durable VS than publicly-insured PWH (ART-naïve: private 70.0% vs public 53.1%, p = 0.03; ART-experienced: private 80.2% vs public 69.4%, p < 0.0001). Privately-insured PWH had greater durable VS than publicly-insured PWH at hospital clinics (AOR = 1.59, 95% CI: 1.20, 2.12; p = 0.001). CONCLUSIONS: Paradoxical differences between HIV monitoring and durable VS exist among publicly and privately-insured PWH in Washington, DC. Programs serving PWH must improve efforts to address barriers creating inequity in HIV outcomes.


Subject(s)
HIV Infections/epidemiology , Health Services Accessibility/statistics & numerical data , Insurance, Health/statistics & numerical data , Outpatients/statistics & numerical data , Adult , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , Cohort Studies , District of Columbia , Female , HIV Infections/drug therapy , Humans , Logistic Models , Male , Medicaid , Medicare/statistics & numerical data , Middle Aged , Retrospective Studies , United States , Young Adult
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