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1.
Immunity ; 56(7): 1649-1663.e5, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37236188

RESUMO

Allogeneic hematopoietic stem cell transplantation (alloHSCT) from donors lacking C-C chemokine receptor 5 (CCR5Δ32/Δ32) can cure HIV, yet mechanisms remain speculative. To define how alloHSCT mediates HIV cure, we performed MHC-matched alloHSCT in SIV+, anti-retroviral therapy (ART)-suppressed Mauritian cynomolgus macaques (MCMs) and demonstrated that allogeneic immunity was the major driver of reservoir clearance, occurring first in peripheral blood, then peripheral lymph nodes, and finally in mesenteric lymph nodes draining the gastrointestinal tract. While allogeneic immunity could extirpate the latent viral reservoir and did so in two alloHSCT-recipient MCMs that remained aviremic >2.5 years after stopping ART, in other cases, it was insufficient without protection of engrafting cells afforded by CCR5-deficiency, as CCR5-tropic virus spread to donor CD4+ T cells despite full ART suppression. These data demonstrate the individual contributions of allogeneic immunity and CCR5 deficiency to HIV cure and support defining targets of alloimmunity for curative strategies independent of HSCT.


Assuntos
Infecções por HIV , Transplante de Células-Tronco Hematopoéticas , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Macaca fascicularis , Carga Viral
2.
Proc Natl Acad Sci U S A ; 120(39): e2304513120, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37725643

RESUMO

Nitrate supply is fundamental to support shoot growth and crop performance, but the associated increase in stem height exacerbates the risks of lodging and yield losses. Despite their significance for agriculture, the mechanisms involved in the promotion of stem growth by nitrate remain poorly understood. Here, we show that the elongation of the hypocotyl of Arabidopsis thaliana, used as a model, responds rapidly and persistently to upshifts in nitrate concentration, rather than to the nitrate level itself. The response occurred even in shoots dissected from their roots and required NITRATE TRANSPORTER 1.1 (NRT1.1) in the phosphorylated state (but not NRT1.1 nitrate transport capacity) and NIN-LIKE PROTEIN 7 (NLP7). Nitrate increased PHYTOCHROME INTERACTING FACTOR 4 (PIF4) nuclear abundance by posttranscriptional mechanisms that depended on NRT1.1 and phytochrome B. In response to nitrate, PIF4 enhanced the expression of numerous SMALL AUXIN-UP RNA (SAUR) genes in the hypocotyl. The growth response to nitrate required PIF4, positive and negative regulators of its activity, including AUXIN RESPONSE FACTORs, and SAURs. PIF4 integrates cues from the soil (nitrate) and aerial (shade) environments adjusting plant stature to facilitate access to light.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Nitratos/farmacologia , Fitocromo B , Arabidopsis/genética , Ácidos Indolacéticos , Transportadores de Nitrato , RNA , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
3.
Nature ; 565(7740): 485-489, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30626967

RESUMO

Wood, a type of xylem tissue, originates from cell proliferation of the vascular cambium. Xylem is produced inside, and phloem outside, of the cambium1. Morphogenesis in plants is typically coordinated by organizer cells that direct the adjacent stem cells to undergo programmed cell division and differentiation. The location of the vascular cambium stem cells and whether the organizer concept applies to the cambium are currently unknown2. Here, using lineage-tracing and molecular genetic studies in the roots of Arabidopsis thaliana, we show that cells with a xylem identity direct adjacent vascular cambial cells to divide and function as stem cells. Thus, these xylem-identity cells constitute an organizer. A local maximum of the phytohormone auxin, and consequent expression of CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) transcription factors, promotes xylem identity and cellular quiescence of the organizer cells. Additionally, the organizer maintains phloem identity in a non-cell-autonomous fashion. Consistent with this dual function of the organizer cells, xylem and phloem originate from a single, bifacial stem cell in each radial cell file, which confirms the classical theory of a uniseriate vascular cambium3. Clones that display high levels of ectopically activated auxin signalling differentiate as xylem vessels; these clones induce cell divisions and the expression of cambial and phloem markers in the adjacent cells, which suggests that a local auxin-signalling maximum is sufficient to specify a stem-cell organizer. Although vascular cambium has a unique function among plant meristems, the stem-cell organizer of this tissue shares features with the organizers of root and shoot meristems.


Assuntos
Arabidopsis/citologia , Arabidopsis/metabolismo , Câmbio/citologia , Câmbio/metabolismo , Ácidos Indolacéticos/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Diferenciação Celular , Divisão Celular , Linhagem da Célula , Meristema/citologia , Meristema/metabolismo , Floema/citologia , Floema/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/citologia , Brotos de Planta/metabolismo , Fatores de Transcrição/metabolismo , Xilema/citologia , Xilema/metabolismo
4.
PLoS Genet ; 18(9): e1010375, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121899

RESUMO

In plants, regulated cell expansion determines organ size and shape. Several members of the family of redundantly acting Small Auxin Up RNA (SAUR) proteins can stimulate plasma membrane (PM) H+-ATPase proton pumping activity by inhibiting PM-associated PP2C.D phosphatases, thereby increasing the PM electrochemical potential, acidifying the apoplast, and stimulating cell expansion. Similarly, Arabidopsis thaliana SAUR63 was able to increase growth of various organs, antagonize PP2C.D5 phosphatase, and increase H+-ATPase activity. Using a gain-of-function approach to bypass genetic redundancy, we dissected structural requirements for SAUR63 growth-promoting activity. The divergent N-terminal domain of SAUR63 has a predicted basic amphipathic α-helix and was able to drive partial PM association. Deletion of the N-terminal domain decreased PM association of a SAUR63 fusion protein, as well as decreasing protein level and eliminating growth-promoting activity. Conversely, forced PM association restored ability to promote H+-ATPase activity and cell expansion, indicating that SAUR63 is active when PM-associated. Lipid binding assays and perturbations of PM lipid composition indicate that the N-terminal domain can interact with PM anionic lipids. Mutations in the conserved SAUR domain also reduced PM association in root cells. Thus, both the N-terminal domain and the SAUR domain may cooperatively mediate the SAUR63 PM association required to promote growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Lipídeos , Monoéster Fosfórico Hidrolases/genética , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Prótons , RNA/metabolismo
5.
PLoS Pathog ; 18(3): e1010396, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35358290

RESUMO

The CCR5-specific antibody Leronlimab is being investigated as a novel immunotherapy that can suppress HIV replication with minimal side effects. Here we studied the virological and immunological consequences of Leronlimab in chronically CCR5-tropic HIV-1 infected humans (n = 5) on suppressive antiretroviral therapy (ART) and in ART-naïve acutely CCR5-tropic SHIV infected rhesus macaques (n = 4). All five human participants transitioned from daily combination ART to self-administered weekly subcutaneous (SC) injections of 350 mg or 700 mg Leronlimab and to date all participants have sustained virologic suppression for over seven years. In all participants, Leronlimab fully occupied CCR5 receptors on peripheral blood CD4+ T cells and monocytes. In ART-naïve rhesus macaques acutely infected with CCR5-tropic SHIV, weekly SC injections of 50 mg/kg Leronlimab fully suppressed plasma viremia in half of the macaques. CCR5 receptor occupancy by Leronlimab occurred concomitant with rebound of CD4+ CCR5+ T-cells in peripheral blood, and full CCR5 receptor occupancy was found in multiple anatomical compartments. Our results demonstrate that weekly, self-administered Leronlimab was safe, well-tolerated, and efficacious for long-term virologic suppression and should be included in the arsenal of safe, easily administered, longer-acting antiretroviral treatments for people living with HIV-1. Trial Registration: ClinicalTrials.gov Identifiers: NCT02175680 and NCT02355184.


Assuntos
Vírus da Imunodeficiência Símia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Anti-HIV , Humanos , Macaca mulatta , Receptores CCR5
6.
Plant Physiol ; 192(3): 2336-2355, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37032117

RESUMO

Fruit formation depends on successful fertilization and is highly sensitive to weather fluctuations that affect pollination. Auxin promotes fruit initiation and growth following fertilization. Class A auxin response factors (Class A ARFs) repress transcription in the absence of auxin and activate transcription in its presence. Here, we explore how multiple members of the ARF family regulate fruit set and fruit growth in tomato (Solanum lycopersicum) and Arabidopsis thaliana, and test whether reduction of SlARF activity improves yield stability in fluctuating temperatures. We found that several tomato Slarf mutant combinations produced seedless parthenocarpic fruits, most notably mutants deficient in SlARF8A and SlARF8B genes. Arabidopsis Atarf8 mutants deficient in the orthologous gene had less complete parthenocarpy than did tomato Slarf8a Slarf8b mutants. Conversely, Atarf6 Atarf8 double mutants had reduced fruit growth after fertilization. AtARF6 and AtARF8 likely switch from repression to activation of fruit growth in response to a fertilization-induced auxin increase in gynoecia. Tomato plants with reduced SlARF8A and SlARF8B gene dosage had substantially higher yield than the wild type under controlled or ambient hot and cold growth conditions. In field trials, partial reduction in the SlARF8 dose increased yield under extreme temperature with minimal pleiotropic effects. The stable yield of the mutant plants resulted from a combination of early onset of fruit set, more fruit-bearing branches and more flowers setting fruits. Thus, ARF8 proteins mediate the control of fruit set, and relieving this control with Slarf8 mutations may be utilized in breeding to increase yield stability in tomato and other crops.


Assuntos
Arabidopsis , Solanum lycopersicum , Ácidos Indolacéticos/metabolismo , Frutas/metabolismo , Solanum lycopersicum/genética , Melhoramento Vegetal , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
PLoS Pathog ; 17(7): e1009738, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34283885

RESUMO

Broadly neutralizing antibodies (bNAbs) directed to HIV-1 have shown promise at suppressing viremia in animal models. However, the use of bNAbs for the central nervous system (CNS) infection is confounded by poor penetration of the blood brain barrier (BBB). Typically, antibody concentrations in the CNS are extremely low; with levels in cerebrospinal fluid (CSF) only 0.1% of blood concentrations. Using a novel nanotechnology platform, which we term nanocapsules, we show effective transportation of the human bNAb PGT121 across the BBB in infant rhesus macaques upon systemic administration up to 1.6% of plasma concentration. We demonstrate that a single dose of PGT121 encased in nanocapsules when delivered at 48h post-infection delays early acute infection with SHIVSF162P3 in infants, with one of four animals demonstrating viral clearance. Importantly, the nanocapsule delivery of PGT121 improves suppression of SHIV infection in the CNS relative to controls.


Assuntos
Anticorpos Antivirais/administração & dosagem , Encéfalo/virologia , Anticorpos Amplamente Neutralizantes/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Carga Viral/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Barreira Hematoencefálica , Encéfalo/efeitos dos fármacos , Humanos , Macaca mulatta , Nanocápsulas , Vírus da Imunodeficiência Símia
8.
J Immunol ; 207(12): 2913-2921, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34810222

RESUMO

CD8+ T cells are key mediators of antiviral and antitumor immunity. The isolation and study of Ag-specific CD8+ T cells, as well as mapping of their MHC restriction, has practical importance to the study of disease and the development of therapeutics. Unfortunately, most experimental approaches are cumbersome, owing to the highly variable and donor-specific nature of MHC-bound peptide/TCR interactions. Here we present a novel system for rapid identification and characterization of Ag-specific CD8+ T cells, particularly well suited for samples with limited primary cells. Cells are stimulated ex vivo with Ag of interest, followed by live cell sorting based on surface-trapped TNF-α. We take advantage of major advances in single-cell sequencing to generate full-length sequence data from the paired TCR α- and ß-chains from these Ag-specific cells. The paired TCR chains are cloned into retroviral vectors and used to transduce donor CD8+ T cells. These TCR transductants provide a virtually unlimited experimental reagent, which can be used for further characterization, such as minimal epitope mapping or identification of MHC restriction, without depleting primary cells. We validated this system using CMV-specific CD8+ T cells from rhesus macaques, characterizing an immunodominant Mamu-A1*002:01-restricted epitope. We further demonstrated the utility of this system by mapping a novel HLA-A*68:02-restricted HIV Gag epitope from an HIV-infected donor. Collectively, these data validate a new strategy to rapidly identify novel Ags and characterize Ag-specific CD8+ T cells, with applications ranging from the study of infectious disease to immunotherapeutics and precision medicine.


Assuntos
Linfócitos T CD8-Positivos , Infecções por HIV , Animais , Epitopos , Epitopos de Linfócito T , Macaca mulatta , Receptores de Antígenos de Linfócitos T , Fator de Necrose Tumoral alfa
9.
Cell Mol Life Sci ; 79(12): 603, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36434396

RESUMO

Ataxia telangiectasia mutated (ATM) is a serine-threonine protein kinase and important regulator of the DNA damage response (DDR). One critical ATM target is the structural subunit A (PR65-S401) of protein phosphatase 2A (PP2A), known to regulate diverse cellular processes such as mitosis and cell growth as well as dephosphorylating many proteins during the recovery from the DDR. We generated mouse embryonic fibroblasts expressing PR65-WT, -S401A (cannot be phosphorylated), and -S401D (phospho-mimetic) transgenes. Significantly, S401 mutants exhibited extensive chromosomal aberrations, impaired DNA double-strand break (DSB) repair and underwent increased mitotic catastrophe after radiation. Both S401A and the S401D cells showed impaired DSB repair (nonhomologous end joining and homologous recombination repair) and exhibited delayed DNA damage recovery, which was reflected in reduced radiation survival. Furthermore, S401D cells displayed increased ERK and AKT signaling resulting in enhanced growth rate further underscoring the multiple roles ATM-PP2A signaling plays in regulating prosurvival responses. Time-lapse video and cellular localization experiments showed that PR65 was exported to the cytoplasm after radiation by CRM1, a nuclear export protein, in line with the very rapid pleiotropic effects observed. A putative nuclear export sequence (NES) close to S401 was identified and when mutated resulted in aberrant PR65 shuttling. Our study demonstrates that the phosphorylation of a single, critical PR65 amino acid (S401) by ATM fundamentally controls the DDR, and balances DSB repair quality, cell survival and growth by spatiotemporal PR65 nuclear-cytoplasmic shuttling mediated by the nuclear export receptor CRM1.


Assuntos
Ataxia Telangiectasia , Animais , Camundongos , Ataxia Telangiectasia/genética , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/metabolismo , Proteínas Nucleares/metabolismo , Dano ao DNA
10.
Med Ref Serv Q ; 42(1): 31-37, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36862611

RESUMO

There is a lack of research evaluating the role of references in hospital policies. The goal of this study was to describe the type of literature used as a reference in medication policies and evaluate the agreement of the policy with evidence-based guidelines. One hundred forty-seven pharmacy owned policies met inclusion criteria; 27.2% of the policies contained references, in which tertiary literature was the most frequently cited source (90%), followed by primary (47.5%), and lastly secondary (27.5%). When references were used, all policies agreed with current guidelines. For policies without references, 3.7% disagreed with published guidelines. Disagreement with guidelines may negatively impact patient care, therefore health systems should incorporate librarians into clinical policy development and review to ensure the best available evidence is incorporated into polices.


Assuntos
Bibliotecários , Serviço de Farmácia Hospitalar , Humanos , Hospitais , Políticas
11.
Development ; 146(14)2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31262724

RESUMO

In flowering plants, anther dehiscence and pollen release are essential for sexual reproduction. Anthers dehisce after cell wall degradation weakens stomium cell junctions in each anther locule, and desiccation creates mechanical forces that open the locules. Either effect or both together may break stomium cell junctions. The microRNA miR167 negatively regulates ARF6 and ARF8, which encode auxin response transcription factors. Arabidopsis mARF6 or mARF8 plants with mutated miR167 target sites have defective anther dehiscence and ovule development. Null mir167a mutations recapitulated mARF6 and mARF8 anther and ovule phenotypes, indicating that MIR167a is the main miR167 precursor gene that delimits ARF6 and ARF8 expression in these organs. Anthers of mir167a or mARF6/8 plants overexpressed genes encoding cell wall loosening functions associated with cell expansion, and grew larger than wild-type anthers did starting at flower stage 11. Experimental desiccation enabled dehiscence of miR167-deficient anthers, indicating competence to dehisce. Conversely, high humidity conditions delayed anther dehiscence in wild-type flowers. These results support a model in which miR167-mediated anther growth arrest permits anther dehiscence. Without miR167 regulation, excess anther growth delays dehiscence by prolonging desiccation.


Assuntos
Flores/crescimento & desenvolvimento , Flores/genética , MicroRNAs/fisiologia , Óvulo Vegetal/crescimento & desenvolvimento , Agrobacterium tumefaciens , Arabidopsis , Sobrevivência Celular/genética , Parede Celular/metabolismo , Desidratação/genética , Desidratação/metabolismo , Regulação da Expressão Gênica de Plantas , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Fenótipo , Plantas Geneticamente Modificadas , Pólen/genética , Pólen/metabolismo
12.
PLoS Pathog ; 16(3): e1008339, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32163523

RESUMO

Despite the success of antiretroviral therapy (ART) to halt viral replication and slow disease progression, this treatment is not curative and there remains an urgent need to develop approaches to clear the latent HIV reservoir. The human IL-15 superagonist N-803 (formerly ALT-803) is a promising anti-cancer biologic with potent immunostimulatory properties that has been extended into the field of HIV as a potential "shock and kill" therapeutic for HIV cure. However, the ability of N-803 to reactivate latent virus and modulate anti-viral immunity in vivo under the cover of ART remains undefined. Here, we show that in ART-suppressed, simian-human immunodeficiency virus (SHIV)SF162P3-infected rhesus macaques, subcutaneous administration of N-803 activates and mobilizes both NK cells and SHIV-specific CD8+ T cells from the peripheral blood to lymph node B cell follicles, a sanctuary site for latent virus that normally excludes such effector cells. We observed minimal activation of memory CD4+ T cells and no increase in viral RNA content in lymph node resident CD4+ T cells post N-803 administration. Accordingly, we found no difference in the number or magnitude of plasma viremia timepoints between treated and untreated animals during the N-803 administration period, and no difference in the size of the viral DNA cell-associated reservoir post N-803 treatment. These results substantiate N-803 as a potent immunotherapeutic candidate capable of activating and directing effector CD8+ T and NK cells to the B cell follicle during full ART suppression, and suggest N-803 must be paired with a bona fide latency reversing agent in vivo to facilitate immune-mediated modulation of the latent viral reservoir.


Assuntos
Antirretrovirais/administração & dosagem , Linfócitos B/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Interleucina-15/antagonistas & inibidores , Células Matadoras Naturais/efeitos dos fármacos , Proteínas/administração & dosagem , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Infecções por HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/fisiopatologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Interleucina-15/genética , Interleucina-15/imunologia , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Macaca mulatta , Proteínas Recombinantes de Fusão , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/fisiologia , Latência Viral/efeitos dos fármacos
13.
Plant Physiol ; 185(1): 256-273, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33631805

RESUMO

Activation of plasma membrane (PM) H+-ATPase activity is crucial in guard cells to promote light-stimulated stomatal opening, and in growing organs to promote cell expansion. In growing organs, SMALL AUXIN UP RNA (SAUR) proteins inhibit the PP2C.D2, PP2C.D5, and PP2C.D6 (PP2C.D2/5/6) phosphatases, thereby preventing dephosphorylation of the penultimate phosphothreonine of PM H+-ATPases and trapping them in the activated state to promote cell expansion. To elucidate whether SAUR-PP2C.D regulatory modules also affect reversible cell expansion, we examined stomatal apertures and conductances of Arabidopsis thaliana plants with altered SAUR or PP2C.D activity. Here, we report that the pp2c.d2/5/6 triple knockout mutant plants and plant lines overexpressing SAUR fusion proteins exhibit enhanced stomatal apertures and conductances. Reciprocally, saur56 saur60 double mutants, lacking two SAUR genes normally expressed in guard cells, displayed reduced apertures and conductances, as did plants overexpressing PP2C.D5. Although altered PM H+-ATPase activity contributes to these stomatal phenotypes, voltage clamp analysis showed significant changes also in K+ channel gating in lines with altered SAUR and PP2C.D function. Together, our findings demonstrate that SAUR and PP2C.D proteins act antagonistically to facilitate stomatal movements through a concerted targeting of both ATP-dependent H+ pumping and channel-mediated K+ transport.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Ácidos Indolacéticos/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Estômatos de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Ecótipo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Reguladores de Crescimento de Plantas/metabolismo
14.
AIDS Behav ; 26(10): 3185-3198, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35362905

RESUMO

The World Health Organization identified men as an essential group to target with HIV testing and treatment strategies;: men who have sex with men (MSM) and male clients of female sex workers (CFSW) account for 35% of new HIV infections globally. Using a cross-sectional design from a community-based HIV prevention project in Tanzania (October 2015-September 2018) and multivariable logistic regression, we identified predictors of HIV seropositivity among men. Of 1,041,343 men on their initial visit to the project, 36,905 (3.5%) were MSM; 567,005 (54.5%) were CFSW; and 437,343 (42.0%) were other men living near hotspots (OMHA). Three predictors of HIV seropositivity emerged across all three groups: being uncircumcised, having sexually transmitted infection symptoms, and harmful drinking of alcohol before sex. Any reported form of gender-based violence among MSM and OMHA and inconsistent condom use among CFSW were associated with HIV seropositivity. These findings may inform community HIV strategies like self-testing, delivery of pre-exposure prophylaxis and antiretroviral therapy, and behavioral change communication targeting men at higher risk of infection.


Assuntos
Infecções por HIV , Soropositividade para HIV , Profissionais do Sexo , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Estudos Transversais , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Infecções Sexualmente Transmissíveis/prevenção & controle , Tanzânia/epidemiologia
15.
J Immunol ; 204(8): 2169-2176, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32161099

RESUMO

Currently 247 million people are living with chronic hepatitis B virus infection (CHB), and the development of novel curative treatments is urgently needed. Immunotherapy is an attractive approach to treat CHB, yet therapeutic approaches to augment the endogenous hepatitis B virus (HBV)-specific T cell response in CHB patients have demonstrated little success. In this study, we show that strain 68-1 rhesus macaque (RM) CMV vaccine vectors expressing HBV Ags engender HBV-specific CD8+ T cells unconventionally restricted by MHC class II and the nonclassical MHC-E molecule in RM. Surface staining of human donor and RM primary hepatocytes (PH) ex vivo revealed the majority of PH expressed MHC-E but not MHC class II. HBV-specific, MHC-E-restricted CD8+ T cells from RM vaccinated with RM CMV vaccine vectors expressing HBV Ags recognized HBV-infected PH from both human donor and RM. These results provide proof-of-concept that MHC-E-restricted CD8+ T cells could be harnessed for the treatment of CHB, either through therapeutic vaccination or adoptive immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatócitos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Animais , Hepatite B Crônica/virologia , Hepatócitos/virologia , Macaca mulatta
16.
BMC Public Health ; 22(1): 304, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35164707

RESUMO

BACKGROUND: Female sex workers (FSW) and men having sex with men (MSM) in Kenya have high rates of HIV infection. Following a 2015 WHO recommendation, Kenya initiated national scale-up of pre-exposure prophylaxis (PrEP) for all persons at high-risk. Concerns have been raised about PrEP users' potential changes in sexual behaviors such adopting condomless sex and multiple partners as a result of perceived reduction in HIV risk, a phenomenon known as risk compensation. Increased condomless sex may lead to unintended pregnancies and sexually transmitted infections and has been described in research contexts but not in the programmatic setting. This study looks at changes in condom use among FSW and MSM on PrEP through a national a scale-up program. METHODS: Routine program data collected between February 2017 and December 2019 were used to assess changes in condom use during the first three months of PrEP in 80 health facilities supported by a scale-up project, Jilinde. The primary outcome was self-reported condom use. Analyses were conducted separately for FSW and for MSM. Log-Binomial Regression with Generalized Estimating Equations was used to compare the incidence proportion ("risk") of consistent condom use at the month 1, and month 3 visits relative to the initiation visit. RESULTS: At initiation, 69% of FSW and 65% of MSM reported consistent condom use. At month 3, this rose to 87% for FSW and 91% for MSM. MSM were 24% more likely to report consistent condom use at month 1 (Relative Risk [RR], 1.24, 95% Confidence Interval [CI], 1.18-1.30) and 40% more likely at month 3 (RR, 1.40, 95% CI, 1.33-1.47) compared to at initiation. FSW were 15% more likely to report consistent condom use at the month one visit (RR, 1.15, 95% CI, 1.13-1.17) and 27% more likely to report condom use on the month 3 visit (RR 1.27, 95% CI, 1.24-1.29). CONCLUSION: Condom use increased substantially among both FSW and MSM. This may be because oral PrEP was provided as part of a combination prevention strategy that included counseling and condoms but could also be due to the low retention rates among those who initiated.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Profissionais do Sexo , Minorias Sexuais e de Gênero , Fármacos Anti-HIV/uso terapêutico , Preservativos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Quênia/epidemiologia , Masculino , Comportamento Sexual , Parceiros Sexuais
17.
J Am Pharm Assoc (2003) ; 62(5): 1477-1498.e8, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35718715

RESUMO

BACKGROUND: The Centers for Medicare and Medicaid (CMS) established the Hospital Readmissions Reduction Program (HRRP) to reduce reimbursement payments to hospitals with excessive patient readmissions. Because of this program, hospitals have developed transitions of care (TOC) programs to improve patient outcomes. OBJECTIVES: To identify and uniformly summarize the impact of pharmacy-led TOC interventions on 30-day readmission rates since the implementation of CMS HRRP. METHODS: This study followed an a-priori protocol that was registered to International Prospective Register of Systematic Reviews. A systematic search was conducted using PubMed, EMBASE, International Pharmaceutical Abstracts, and CINAHL from January 1, 2013 through January 14, 2022. Studies were included if they met the following criteria: pharmacy-led intervention, 30-day readmission outcomes, patients at least 18 years old, original research performed in the United States, and English language only articles. Descriptive statistics were used to summarize study characteristics, outcomes, and elements of the study interventions. RESULTS: A total of 1964 abstracts were screened with 123 studies being included in the review. A total of 110 (89.4%) studies showed a decrease in readmission rates. The largest decrease in readmission rates was 44.5% (range 0.2%-44.5%, median = 7.4%) and the most common pharmacy-led intervention was patient counseling (n = 119, 96.7%) followed by medication reconciliation (n = 111, 90.2%). High-risk patient populations were commonly targeted with 52 studies (42.3%) focusing on CMS HRRP related diagnoses. CONCLUSION: Most pharmacist-led TOC interventions contributed to lower rates of 30-day readmission. Future studies should investigate the types of interventions that most significantly impact readmission rates.


Assuntos
Readmissão do Paciente , Farmácia , Adolescente , Idoso , Humanos , Hospitais , Medicare , Alta do Paciente , Transferência de Pacientes/métodos , Estados Unidos
18.
Analyst ; 146(4): 1157-1162, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33426547

RESUMO

Adaptive resistance is a major limitation in the use of targeted therapies for cancer. Using real time biomass tracking, we demonstrate the isolation and identification of rare (1% fraction) diffuse large B cell lymphoma cells resistant to the PI3K inhibitor idelalisib, from an otherwise sensitive population. This technique allows direct study of these rare, drug tolerant cells.


Assuntos
Linfoma Difuso de Grandes Células B , Fosfatidilinositol 3-Quinases , Biomassa , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia
19.
J Med Libr Assoc ; 109(2): 323-329, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34285676

RESUMO

BACKGROUND: In 2015, librarians at Purdue University began fielding requests from many disciplines to consult or collaborate on systematic review projects, and in 2016, health sciences librarians led the launch of a formal systematic review service. In 2019, Purdue University Libraries was reorganized as the Libraries and School of Information Studies (PULSIS) and assigned its own course designation, ILS. The increase in calls for systematic review services and the ability to teach ILS courses inspired the development of a credit-bearing ILS systematic review course. CASE PRESENTATION: We designed, taught, and assessed a one-credit systematic review course for graduate students, using a backward-design course development model and applying self-determination theoretical concepts into lessons, assignments, and assessments. Using qualitative pre- and post-assessments, we discovered a variety of themes around student motivations, expectations, and preferences for the course. In quantitative post-class assessments, students reported improved confidence in all systematic review processes, with the highest confidence in their ability to choose and use citation management managers, describe the steps in the systematic review process, and understand the importance of a reproducible and systematic search strategy. CONCLUSIONS: We considered our pilot a success. Next steps include testing 2- and 3-credit- hour models and working to formally integrate the course into departmental and certificate curriculums. This case report provides a model for course design principles, learning outcomes, and assessments that librarians and library administrators can use to adjust their systematic review services.


Assuntos
Currículo , Bibliotecários , Revisões Sistemáticas como Assunto , Humanos , Aprendizagem , Estudantes
20.
J Virol ; 93(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31315990

RESUMO

Major histocompatibility complex E (MHC-E) is a highly conserved nonclassical MHC-Ib molecule that tightly binds peptides derived from leader sequences of classical MHC-Ia molecules for presentation to natural killer cells. However, MHC-E also binds diverse foreign and neoplastic self-peptide antigens for presentation to CD8+ T cells. Although the determinants of MHC-E-restricted T cell priming remain unknown, these cells are induced in humans infected with pathogens containing genes that inhibit the transporter associated with antigen processing (TAP). Indeed, mice vaccinated with TAP-inhibited autologous dendritic cells develop T cells restricted by the murine MHC-E homologue, Qa-1b. Here, we tested whether rhesus macaques (RM) vaccinated with viral constructs expressing a TAP inhibitor would develop insert-specific MHC-E-restricted CD8+ T cells. We generated viral constructs coexpressing SIVmac239 Gag in addition to one of three TAP inhibitors: herpes simplex virus 2 ICP47, bovine herpes virus 1 UL49.5, or rhesus cytomegalovirus Rh185. Each TAP inhibitor reduced surface expression of MHC-Ia molecules but did not reduce surface MHC-E expression. In agreement with modulation of surface MHC-Ia levels, TAP inhibition diminished presentation of MHC-Ia-restricted CD8+ T cell epitopes without impacting presentation of peptide antigen bound by MHC-E. Vaccination of macaques with vectors dually expressing SIVmac239 Gag with ICP47, UL49.5, or Rh185 generated Gag-specific CD8+ T cells classically restricted by MHC-Ia but not MHC-E. These data demonstrate that, in contrast to results in mice, TAP inhibition alone is insufficient for priming of MHC-E-restricted T cell responses in primates and suggest that additional unknown mechanisms govern the induction of CD8+ T cells recognizing MHC-E-bound antigen.IMPORTANCE Due to the near monomorphic nature of MHC-E in the human population and inability of many pathogens to inhibit MHC-E-mediated peptide presentation, MHC-E-restricted T cells have become an attractive vaccine target. However, little is known concerning how these cells are induced. Understanding the underlying mechanisms that induce these T cells would provide a powerful new vaccine strategy to an array of neoplasms and viral and bacterial pathogens. Recent studies have indicated a link between TAP inhibition and induction of MHC-E-restricted T cells. The significance of our research is in demonstrating that TAP inhibition alone does not prime MHC-E-restricted T cell generation and suggests that other, currently unknown mechanisms regulate their induction.


Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Inibidores Enzimáticos/metabolismo , Macaca mulatta , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Vacinas contra a SAIDS/administração & dosagem , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
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