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1.
Environ Microbiol ; 26(9): e16697, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39253751

RESUMEN

Bacterial endosymbionts manipulate reproduction in arthropods to increase their prevalence in the host population. One such manipulation is cytoplasmic incompatibility (CI), wherein the bacteria sabotage sperm in infected males to reduce the hatch rate when mated with uninfected females, but zygotes are 'rescued' when that male mates with an infected female. In the spider Mermessus fradeorum (Linyphiidae), Rickettsiella symbionts cause variable levels of CI. We hypothesised that temperature affects the strength of CI and its rescue in M. fradeorum, potentially mediated by bacterial titre. We reared Rickettsiella-infected spiders in two temperature conditions (26°C vs. 20°C) and tested CI induction in males and rescue in females. In incompatible crosses between infected males and uninfected females, the hatch rate from warm males was doubled (mean ± standard error = 0.687 ± 0.052) relative to cool males (0.348 ± 0.046), indicating that CI induction is weaker in warm males. In rescue crosses between infected females and infected males, female rearing temperature had a marginal effect on CI rescue, but the hatch rate remained high for both warm (0.960 ± 0.023) and cool females (0.994 ± 0.004). Bacterial titre, as measured by quantitative polymerase chain reaction, was lower in warm than cool spiders, particularly in females, suggesting that bacterial titre may play a role in causing the temperature-mediated changes in CI.


Asunto(s)
Calor , Arañas , Simbiosis , Animales , Arañas/microbiología , Femenino , Masculino , Citoplasma/microbiología , Coxiellaceae/genética , Reproducción , Temperatura
2.
Sci Rep ; 14(1): 8556, 2024 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609398

RESUMEN

The invasive brown widow spider, Latrodectus geometricus (Araneae: Theridiidae), has spread in multiple locations around the world and, along with it, brought associated organisms such as endosymbionts. We investigated endosymbiont diversity and prevalence across putative native and invasive populations of this spider, predicting lower endosymbiont diversity across the invasive range compared to the native range. First, we characterized the microbial community in the putative native (South Africa) and invasive (Israel and the United States) ranges via high throughput 16S sequencing of 103 adult females. All specimens were dominated by reads from only 1-3 amplicon sequence variants (ASV), and most individuals were infected with an apparently uniform strain of Rhabdochlamydia. We also found Rhabdochlamydia in spider eggs, indicating that it is a maternally-inherited endosymbiont. Relatively few other ASV were detected, but included two variant Rhabdochlamydia strains and several Wolbachia, Spiroplasma and Enterobacteriaceae strains. We then diagnostically screened 118 adult female spiders from native and invasive populations specifically for Rhabdochlamydia and Wolbachia. We found Rhabdochlamydia in 86% of individuals and represented in all populations, which suggests that it is a consistent and potentially important associate of L. geometricus. Wolbachia was found at lower overall prevalence (14%) and was represented in all countries, but not all populations. In addition, we found evidence for geographic variation in endosymbiont prevalence: spiders from Israel were more likely to carry Rhabdochlamydia than those from the US and South Africa, and Wolbachia was geographically clustered in both Israel and South Africa. Characterizing endosymbiont prevalence and diversity is a first step in understanding their function inside the host and may shed light on the process of spread and population variability in cosmopolitan invasive species.


Asunto(s)
Animales Ponzoñosos , Chlamydiales , Arañas , Wolbachia , Humanos , Adulto , Animales , Femenino , Huevos
3.
Am J Kidney Dis ; 83(3): 370-385, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37879527

RESUMEN

All vitamins play essential roles in various aspects of body function and systems. Patients with chronic kidney disease (CKD), including those receiving dialysis, may be at increased risk of developing vitamin deficiencies due to anorexia, poor dietary intake, protein energy wasting, restricted diet, dialysis loss, or inadequate sun exposure for vitamin D. However, clinical manifestations of most vitamin deficiencies are usually subtle or undetected in this population. Testing for circulating levels is not undertaken for most vitamins except folate, B12, and 25-hydroxyvitamin D because assays may not be available or may be costly to perform and do not always correlate with body stores. The last systematic review through 2016 was performed for the Kidney Disease Outcome Quality Initiative (KDOQI) 2020 Nutrition Guideline update, so this article summarizes the more recent evidence. We review the use of vitamins supplementation in the CKD population. To date there have been no randomized trials to support the benefits of any vitamin supplementation for kidney, cardiovascular, or patient-centered outcomes. The decision to supplement water-soluble vitamins should be individualized, taking account the patient's dietary intake, nutritional status, risk of vitamins deficiency/insufficiency, CKD stage, comorbid status, and dialysis loss. Nutritional vitamin D deficiency should be corrected, but the supplementation dose and formulation need to be personalized, taking into consideration the degree of 25-hydroxyvitamin D deficiency, parathyroid hormone levels, CKD stage, and local formulation. Routine supplementation of vitamins A and E is not supported due to potential toxicity. Although more trial data are required to elucidate the roles of vitamin supplementation, all patients with CKD should undergo periodic assessment of dietary intake and aim to receive various vitamins through natural food sources and a healthy eating pattern that includes vitamin-dense foods.


Asunto(s)
Avitaminosis , Insuficiencia Renal Crónica , Deficiencia de Vitamina D , Humanos , Vitaminas/uso terapéutico , Vitamina D , Suplementos Dietéticos , Insuficiencia Renal Crónica/complicaciones , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/etiología , Vitamina A , Avitaminosis/epidemiología , Avitaminosis/complicaciones , Vitamina K
4.
Public Health Rep ; 138(3): 422-427, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36971286

RESUMEN

Limited studies are available on how decisions and perceptions on SARS-CoV-2 vaccination have changed since the start of vaccination availability. We performed a qualitative study to identify factors critical to SARS-CoV-2 vaccination decision making and how perspectives evolved among African American/Black, Native American, and Hispanic communities disproportionately affected by COVID-19 and social and economic disadvantage. We conducted 16 virtual meetings, with 232 participants in wave 1 meetings (December 2020) and with 206 returning participants in wave 2 meetings (January and February 2021). Wave 1 vaccine concerns in all communities included information needs, vaccine safety, and speed of vaccine development. Lack of trust in government and the pharmaceutical industry was influential, particularly among African American/Black and Native American participants. Participants showed more willingness to get vaccinated at wave 2 than at wave 1, indicating that many of their information needs had been addressed. Hesitancy remained greater among African American/Black and Native American participants than among Hispanic participants. Participants in all groups indicated that conversations tailored to their community and with those most trustworthy to them would be helpful. To overcome vaccine hesitancy, we propose a model of fully considered SARS-CoV-2 vaccine decision making, whereby public health departments supply information, align with community values and recognize lived experiences, offer support for decision making, and make vaccination easy and convenient.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Toma de Decisiones , Humanos , Indio Americano o Nativo de Alaska/psicología , Negro o Afroamericano/psicología , COVID-19/prevención & control , Vacunas contra la COVID-19/administración & dosificación , Hispánicos o Latinos/psicología , SARS-CoV-2 , Vacunación/psicología
5.
J Clin Invest ; 133(6)2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36602866

RESUMEN

BackgroundAntiretroviral therapy (ART) halts HIV-1 replication, decreasing viremia to below the detection limit of clinical assays. However, some individuals experience persistent nonsuppressible viremia (NSV) originating from CD4+ T cell clones carrying infectious proviruses. Defective proviruses represent over 90% of all proviruses persisting during ART and can express viral genes, but whether they can cause NSV and complicate ART management is unknown.MethodsWe undertook an in-depth characterization of proviruses causing NSV in 4 study participants with optimal adherence and no drug resistance. We investigated the impact of the observed defects on 5'-leader RNA properties, virus infectivity, and gene expression. Integration-site specific assays were used to track these proviruses over time and among cell subsets.ResultsClones carrying proviruses with 5'-leader defects can cause persistent NSV up to approximately 103 copies/mL. These proviruses had small, often identical deletions or point mutations involving the major splicing donor (MSD) site and showed partially reduced RNA dimerization and nucleocapsid binding. Nevertheless, they were inducible and produced noninfectious virions containing viral RNA, but lacking envelope.ConclusionThese findings show that proviruses with 5'-leader defects in CD4+ T cell clones can give rise to NSV, affecting clinical care. Sequencing of the 5'-leader can help in understanding failure to completely suppress viremia.FundingOffice of the NIH Director and National Institute of Dental and Craniofacial Research, NIH; Howard Hughes Medical Institute; Johns Hopkins University Center for AIDS Research; National Institute for Allergy and Infectious Diseases (NIAID), NIH, to the PAVE, BEAT-HIV, and DARE Martin Delaney collaboratories.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Provirus/genética , Provirus/metabolismo , VIH-1/genética , VIH-1/metabolismo , Viremia/genética , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Linfocitos T CD4-Positivos , ARN Viral/genética , ARN Viral/metabolismo
6.
PLoS Pathog ; 18(9): e1010845, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36074794

RESUMEN

Antiretroviral therapy (ART) effectively inhibits HIV-1 replication but is not curative due to the persistence of a latent viral reservoir in resting CD4+ T cells. This reservoir is a major barrier to cure. Sequencing studies have revealed that the population of proviruses persisting in ART-treated individuals is dominated by defective proviruses that cannot give rise to viral rebound due to fatal defects including large deletions and APOBEC3-mediated hypermutation. Near full genome sequencing (nFGS) of individual proviruses is used in reservoir assays to provide an estimate of the fraction of proviruses that are intact. nFGS methods rely on a long-distance outer PCR capturing most (~9 kb) of the genome, followed by nested inner PCRs. The outer PCR is carried out at limit dilution, and interpretation of the results is based on the assumption that all proviruses are quantitatively captured. Here, we evaluate nFGS methods using the intact proviral DNA assay (IPDA), a multiplex digital droplet PCR assay that quantitates intact and defective proviruses with single molecule sensitivity using only short, highly efficient amplicons. We analyzed proviral templates of known sequence to avoid the additional complication of sequence polymorphism. With the IPDA, we quantitated molecular yields at each step of nFGS methods. We demonstrate that nFGS methods are inefficient and miss ~70% of full-length proviruses due to amplification failure at the initial outer PCR step. In contrast, proviruses with large internal deletions encompassing 70% of the genome can be quantitatively amplified under the same conditions. Accurate measurement of the latent reservoir of HIV-1 is essential for evaluating the efficacy of cure strategies, and the bias against full length proviruses in nFGS methods must be considered.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Linfocitos T CD4-Positivos , ADN Viral/genética , VIH-1/genética , Humanos , Provirus/genética , Carga Viral
7.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35110411

RESUMEN

In persons living with HIV-1 (PLWH) who start antiretroviral therapy (ART), plasma virus decays in a biphasic fashion to below the detection limit. The first phase reflects the short half-life (<1 d) of cells that produce most of the plasma virus. The second phase represents the slower turnover (t1/2 = 14 d) of another infected cell population, whose identity is unclear. Using the intact proviral DNA assay (IPDA) to distinguish intact and defective proviruses, we analyzed viral decay in 17 PLWH initiating ART. Circulating CD4+ T cells with intact proviruses include few of the rapidly decaying first-phase cells. Instead, this population initially decays more slowly (t1/2 = 12.9 d) in a process that largely represents death or exit from the circulation rather than transition to latency. This more protracted decay potentially allows for immune selection. After ∼3 mo, the decay slope changes, and CD4+ T cells with intact proviruses decay with a half-life of 19 mo, which is still shorter than that of the latently infected cells that persist on long-term ART. Two-long-terminal repeat (2LTR) circles decay with fast and slow phases paralleling intact proviruses, a finding that precludes their use as a simple marker of ongoing viral replication. Proviruses with defects at the 5' or 3' end of the genome show equivalent monophasic decay at rates that vary among individuals. Understanding these complex early decay processes is important for correct use of reservoir assays and may provide insights into properties of surviving cells that can constitute the stable latent reservoir.


Asunto(s)
Antirretrovirales/farmacología , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Provirus/efectos de los fármacos , Virión/efectos de los fármacos , Linfocitos T CD4-Positivos/efectos de los fármacos , Células Cultivadas , ADN Viral/efectos de los fármacos , Humanos , Estudios Longitudinales , Carga Viral/efectos de los fármacos , Latencia del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos
8.
J Am Heart Assoc ; 11(4): e022733, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35112882

RESUMEN

Background Unlike patients with low ejection fraction after an acute coronary syndrome (ACS), little is known about the long-term incidence and influence of cardiovascular events before sudden death among stabilized patients after ACS. Methods and Results A total of 18 144 patients stabilized within 10 days after ACS in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial) were studied. Cumulative incidence rates (IRs) and IRs per 100 patient-years of sudden death were calculated. Using Cox proportional hazards, the association of ≥1 additional postrandomization cardiovascular events (myocardial infarction, stroke, and hospitalization for unstable angina or heart failure) with sudden death was examined. Early (≤1 year after ACS) and late sudden deaths (>1 year) were compared. Of 2446 total deaths, 402 (16%) were sudden. The median time to sudden death was 2.7 years, with 109 early and 293 late sudden deaths. The cumulative IR was 2.47% (95% CI, 2.23%-2.73%) at 7 years of follow-up. The risk of sudden death following a postrandomization cardiovascular event (150/402 [37%] sudden deaths; median 1.4 years) was greater (IR/100 patient-years, 1.45 [95% CI, 1.23-1.69]) than the risk with no postrandomization cardiovascular event (IR/100 patient-years, 0.27 [95% CI, 0.24-0.30]). Postrandomization myocardial infarction (hazard ratio [HR], 3.64 [95% CI, 2.85-4.66]) and heart failure (HR, 4.55 [95% CI, 3.33-6.22]) significantly increased future risk of sudden death. Conclusions Patients stabilized within 10 days of an ACS remain at long-term risk of sudden death with the greatest risk in those with an additional cardiovascular event. These results refine the long-term risk and risk effectors of sudden death, which may help clinicians identify opportunities to improve care. Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00202878.


Asunto(s)
Síndrome Coronario Agudo , Insuficiencia Cardíaca , Infarto del Miocardio , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Síndrome Coronario Agudo/terapia , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Combinación Ezetimiba y Simvastatina , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/epidemiología , Humanos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/epidemiología , Factores de Riesgo , Resultado del Tratamiento
9.
Semin Dial ; 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34378234

RESUMEN

Emerging research suggests that a more liberalized diet, specifically a more plant-based diet resulting in liberalization of potassium intake, for people receiving hemodialysis is necessary and the benefits outweigh previously thought risks. If the prescribed hemodialysis diet is to be liberalized, the need to illuminate and prevent potential pitfalls of a liberalized potassium diet is warranted. This paper explores such topics as partial to full adherence to a liberalized diet and its consequences if any, the advantages of a high-fiber intake, the theoretical risk of anemia when consuming a more plant-dominant diet, the potential benefits against renal acid load and effect on metabolic acidosis with increased fruit and vegetable intake, the putative change in serum potassium levels, carbohydrate quality, and the healthfulness of meat substitutes. The benefits of a more plant-based diet for the hemodialysis population are multifold; however, the possible pitfalls of this type of diet must be reviewed and addressed upon meal planning in order to be avoided.

10.
PLoS Pathog ; 17(6): e1009445, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34181697

RESUMEN

We conducted a longitudinal study of cryptosporidiosis from birth to three years of age in an urban slum of Dhaka Bangladesh. Fecal DNA was extracted from monthly surveillance samples and diarrheal stool samples collected from 392 infants from birth to three years. A pan-Cryptosporidium qPCR assay was used to identify sub-clinical and symptomatic cryptosporidiosis. Anthropometric measurements were collected quarterly to assess child nutritional status. 31% (121/392) of children experienced a single and 57% (222/392) multiple infections with Cryptosporidium. Repeat infections had a lower burden of parasites in the stool (Cq slope = -1.85; p<0.0001) and were more likely to be sub-clinical (Chi square test for trend; p = 0.01). Repeat infections were associated with the development of growth faltering (Pearson correlation = -0.18; p = 0.0004). High levels of fecal IgA antibodies against the Cryptosporidium Cp23 sporozoite protein at one year of life were associated with a delay in reinfection and amelioration of growth faltering through three years of life (HAZ IgA high responders -1.323 ± 0.932 versus HAZ -1.731 ± 0.984 p = 0.0001). We concluded that nonsterile immunity to cryptosporidiosis in young children was associated with high levels of mucosal IgA anti-Cp23 and protection from diarrhea and growth faltering. Trial Registration: NCT02764918.


Asunto(s)
Trastornos de la Nutrición del Niño/inmunología , Trastornos de la Nutrición del Niño/parasitología , Criptosporidiosis/inmunología , Inmunidad Mucosa/inmunología , Inmunoglobulina A/inmunología , Bangladesh , Preescolar , Criptosporidiosis/complicaciones , Diarrea/parasitología , Femenino , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Proteínas Protozoarias/inmunología , Esporozoítos/inmunología
11.
J Clin Invest ; 131(3)2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33301425

RESUMEN

Clonal expansion of infected CD4+ T cells is a major mechanism of HIV-1 persistence and a barrier to achieving a cure. Potential causes are homeostatic proliferation, effects of HIV-1 integration, and interaction with antigens. Here, we show that it is possible to link antigen responsiveness, the full proviral sequence, the integration site, and the T cell receptor ß-chain (TCRß) sequence to examine the role of recurrent antigenic exposure in maintaining the HIV-1 reservoir. We isolated CMV- and Gag-responding CD4+ T cells from 10 treated individuals. Proviral populations in CMV-responding cells were dominated by large clones, including clones harboring replication-competent proviruses. TCRß repertoires showed high clonality driven by converging adaptive responses. Although some proviruses were in genes linked to HIV-1 persistence (BACH2, STAT5B, MKL1), the proliferation of infected cells under antigenic stimulation occurred regardless of the site of integration. Paired TCRß and integration site analysis showed that infection could occur early or late in the course of a clone's response to antigen and could generate infected cell populations too large to be explained solely by homeostatic proliferation. Together, these findings implicate antigen-driven clonal selection as a major factor in HIV-1 persistence, a finding that will be a difficult challenge to eradication efforts.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Selección Clonal Mediada por Antígenos , Infecciones por VIH/inmunología , VIH-1/fisiología , Integración Viral/inmunología , Latencia del Virus/inmunología , Adulto , Linfocitos T CD4-Positivos/patología , Femenino , Infecciones por VIH/terapia , Humanos , Masculino , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología
12.
J Evol Biol ; 33(10): 1507-1511, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32894786

RESUMEN

Maternally transmitted bacterial symbionts can be important mediators of the interactions between insect herbivores and their foodplants. These symbionts are often facultative (present in some host individuals but not others) and can have large effects on their host's phenotype, thus giving rise to heritable variation upon which selection can act. In the cowpea aphid (Aphis craccivora), it has been established that the facultative endosymbiont Arsenophonus improves aphid performance on black locust trees (Robinia pseudoacacia) but not on fava (Vicia faba). Here, we tested whether this fitness differential translated into contemporaneous evolution of aphid populations associated with the different plants. In a laboratory study lasting 16 weeks, we found that the frequency of Arsenophonus-infected individuals significantly increased over time for aphid populations on black locust but declined for aphid populations on fava. By the end of the experiment, Arsenophonus infection was >3× more common on black locust than fava, which is comparable to previously described infection frequencies in natural field populations. Our results clearly demonstrate that aphid populations with mixed facultative symbiont infection status can rapidly evolve in response to the selective environments imposed by different host plants. This selection differential may be a sufficient explanation for the global association between Arsenophonus-infected cowpea aphids and black locust trees, without invoking additional assortative mechanisms. Because the aphid and plant originate from different parts of the world, we further hypothesize that Arsenophonus infection may have acted as a preadaptation that has promoted functional specialization of infected aphids on a novel host plant.


Asunto(s)
Áfidos/genética , Evolución Biológica , Gammaproteobacteria/fisiología , Herbivoria , Selección Genética , Animales , Áfidos/microbiología , Robinia , Simbiosis , Vicia faba
13.
Proc Biol Sci ; 287(1930): 20201107, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32635864

RESUMEN

Many arthropod hosts are infected with bacterial endosymbionts that manipulate host reproduction, but few bacterial taxa have been shown to cause such manipulations. Here, we show that a bacterial strain in the genus Rickettsiella causes cytoplasmic incompatibility (CI) between infected and uninfected hosts. We first surveyed the bacterial community of the agricultural spider Mermessus fradeorum (Linyphiidae) using high throughput sequencing and found that individual spiders can be infected with up to five different strains of maternally inherited symbiont from the genera Wolbachia, Rickettsia, and Rickettsiella. The Rickettsiella strain was pervasive, found in all 23 tested spider matrilines. We used antibiotic curing to generate uninfected matrilines that we reciprocally crossed with individuals infected only with Rickettsiella. We found that only 13% of eggs hatched when uninfected females were mated with Rickettsiella-infected males; in contrast, at least 83% of eggs hatched in the other cross types. This is the first documentation of Rickettsiella, or any Gammaproteobacteria, causing CI. We speculate that induction of CI may be much more widespread among maternally inherited bacteria than previously appreciated. Further, our results reinforce the importance of thoroughly characterizing and assessing the inherited microbiome before attributing observed host phenotypes to well-characterized symbionts such as Wolbachia.


Asunto(s)
Coxiellaceae/fisiología , Citoplasma/microbiología , Arañas/microbiología , Animales , Femenino , Interacciones Huésped-Patógeno , Masculino , Simbiosis
14.
Proc Natl Acad Sci U S A ; 117(31): 18692-18700, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32690683

RESUMEN

A scalable approach for quantifying intact HIV-1 proviruses is critical for basic research and clinical trials directed at HIV-1 cure. The intact proviral DNA assay (IPDA) is a novel approach to characterizing the HIV-1 reservoir, focusing on the genetic integrity of individual proviruses independent of transcriptional status. It uses multiplex digital droplet PCR to distinguish and separately quantify intact proviruses, defined by a lack of overt fatal defects such as large deletions and APOBEC3G-mediated hypermutation, from the majority of proviruses that have such defects. This distinction is important because only intact proviruses cause viral rebound on ART interruption. To evaluate IPDA performance and provide benchmark data to support its implementation, we analyzed peripheral blood samples from 400 HIV-1+ adults on ART from several diverse cohorts, representing a robust sample of treated HIV-1 infection in the United States. We provide direct quantitative evidence that defective proviruses greatly outnumber intact proviruses (by >12.5 fold). However, intact proviruses are present at substantially higher frequencies (median, 54/106 CD4+ T cells) than proviruses detected by the quantitative viral outgrowth assay, which requires induction and in vitro growth (∼1/106 CD4+ T cells). IPDA amplicon signal issues resulting from sequence polymorphisms were observed in only 6.3% of individuals and were readily apparent and easily distinguished from low proviral frequency, an advantage of the IPDA over standard PCR assays which generate false-negative results in such situations. The large IPDA dataset provided here gives the clearest quantitative picture to date of HIV-1 proviral persistence on ART.


Asunto(s)
ADN Viral/sangre , Infecciones por VIH , Provirus/genética , Latencia del Virus/genética , Adulto , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos
15.
Am Heart J ; 223: 87-97, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32203684

RESUMEN

BACKGROUND: The evolution and clinical impact of cardiac remodeling after large ST-elevation myocardial infarction (STEMI) is not well delineated in the current therapeutic era. METHODS: The PRESERVATION I trial longitudinally assessed cardiac structure and function in STEMI patients receiving primary percutaneous coronary intervention (PCI). Echocardiograms were performed immediately post-PCI and at 1, 3, 6 and 12 months after STEMI. The extent of cardiac remodeling was assessed in patients with ejection fraction (EF) ≤ 40% after PCI. Patients were stratified by the presence or absence of reverse remodeling, defined as an increase in end-diastolic volume (EDV) of ≤10 mL or decrease in EDV at 1 month, and evaluated for an association with adverse events at 1 year. RESULTS: Of the 303 patients with large STEMI enrolled in PRESERVATION I, 225 (74%) had at least moderately reduced systolic function (mean EF 32 ±â€¯5%) immediately after primary PCI. In the following year, there were significant increases in EF and LV volumes, with the greatest magnitude of change occurring in the first month. At 1 month, 104 patients (46%) demonstrated reverse remodeling, which was associated with a significantly lower rate of death, recurrent myocardial infarction and repeat cardiovascular hospitalization at 1 year (HR 0.44; 95% CI: 0.19-0.99). CONCLUSION: Reduced EF after large STEMI and primary PCI is common in the current therapeutic era. The first month following primary reperfusion is a critical period during which the greatest degree of cardiac remodeling occurs. Patients demonstrating early reverse remodeling have a significantly lower rate of adverse events in the year after STEMI.


Asunto(s)
Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST/patología , Infarto del Miocardio con Elevación del ST/cirugía , Remodelación Ventricular , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Tiempo
17.
J Am Coll Cardiol ; 75(3): 289-300, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31976867

RESUMEN

BACKGROUND: Mechanistic studies have shown that morphine blunts the antiplatelet effects of oral adenosine diphosphate receptor blockers. However, the clinical relevance of this interaction is controversial. OBJECTIVES: This study sought to explore the association between morphine and ischemic events in 5,438 patients treated with concomitant clopidogrel presenting with non-ST-segment elevation acute coronary syndromes (NSTEACS) in the EARLY ACS (Early Glycoprotein IIb/IIIa Inhibition in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome) trial. Patients not treated with clopidogrel (n = 3,462) were used as negative controls. METHODS: Endpoints were the composite of death, myocardial infarction (MI), recurrent ischemia, or thrombotic bailout at 96 h (4-way endpoint) and the composite of death or MI at 30 days. RESULTS: In patients treated with clopidogrel, morphine use was associated with higher rates of the 4-way endpoint at 96 h (adjusted odds ratio [OR]: 1.40; 95% confidence interval [CI]: 1.04 to 1.87; p = 0.026). There was a trend for higher rates of death or MI at 30 days (adjusted OR: 1.29; 95% CI: 0.98 to 1.70; p = 0.072), driven by events in the first 48 h (adjusted hazard ratio: 1.54; 95% CI: 1.07 to 2.23; p = 0.021). In patients not treated with clopidogrel, morphine was not associated with either the 4-way endpoint at 96 h (adjusted OR: 1.05; 95% CI: 0.74 to 1.49; p = 0.79; pinteraction = 0.36 ) or death or MI at 30 days (adjusted OR: 1.07; 95% CI: 0.77 to 1.48; p = 0.70; pinteraction = 0.46). CONCLUSIONS: When used concomitantly with clopidogrel pre-treatment, morphine was associated with higher rates of ischemic events in patients with NSTEACS. (EARLY ACS: Early Glycoprotein IIb/IIIa Inhibition in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome; NCT00089895).


Asunto(s)
Síndrome Coronario Agudo/diagnóstico por imagen , Analgésicos Opioides/administración & dosificación , Angiografía Coronaria/métodos , Morfina/administración & dosificación , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Síndrome Coronario Agudo/tratamiento farmacológico , Anciano , Analgésicos Opioides/efectos adversos , Clopidogrel/administración & dosificación , Angiografía Coronaria/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morfina/efectos adversos , Infarto del Miocardio sin Elevación del ST/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/administración & dosificación , Resultado del Tratamiento
18.
Microb Ecol ; 79(2): 472-481, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31300838

RESUMEN

Maternally inherited bacterial endosymbionts are common in arthropods, but their distribution and prevalence are poorly characterized in many host taxa. Initial surveys have suggested that vertically transmitted symbionts may be particularly common in spiders (Araneae). Here, we used diagnostic PCR and high-throughput sequencing to evaluate symbiont infection in 267 individual spiders representing 14 species (3 families) of agricultural spiders. We found 27 operational taxonomic units (OTUs) that are likely endosymbiotic, including multiple strains of Wolbachia, Rickettsia, and Cardinium, which are all vertically transmitted and frequently associated with reproductive manipulation of arthropod hosts. Additional strains included Rickettsiella, Spiroplasma, Rhabdochlamydia, and a novel Rickettsiales, all of which could range from pathogenic to mutualistic in their effects upon their hosts. Seventy percent of spider species had individuals that tested positive for one or more endosymbiotic OTUs, and specimens frequently contained multiple symbiotic strain types. The most symbiont-rich species, Idionella rugosa, had eight endosymbiotic OTUs, with as many as five present in the same specimen. Individual specimens within infected spider species had a variety of symbiotypes, differing from one another in the presence or absence of symbiotic strains. Our sample included both starved and unstarved specimens, and dominant bacterial OTUs were consistent per host species, regardless of feeding status. We conclude that spiders contain a remarkably diverse symbiotic microbiota. Spiders would be an informative group for investigating endosymbiont population dynamics in time and space, and unstarved specimens collected for other purposes (e.g., food web studies) could be used, with caution, for such investigations.


Asunto(s)
Bacterias/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Entomología/métodos , Microbiota , Arañas/microbiología , Simbiosis/fisiología , Animales , Bacterias/clasificación , Fenómenos Fisiológicos Bacterianos , Privación de Alimentos , Secuenciación de Nucleótidos de Alto Rendimiento , Kentucky , Microbiota/genética , Reacción en Cadena de la Polimerasa
19.
JAMA Cardiol ; 4(9): 846-854, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31314050

RESUMEN

Importance: Limited evidence is available regarding the benefit and hazard of higher-intensity treatment to lower lipid levels among patients 75 years or older. As a result, guideline recommendations differ for this age group compared with younger patients. Objective: To determine the effect on outcomes and risks of combination ezetimibe and simvastatin compared with simvastatin monotherapy to lower lipid levels among patients 75 years or older with stabilized acute coronary syndrome (ACS). Design, Setting, Participants: In this prespecified secondary analysis of the global, multicenter, prospective clinical randomized Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT), outcomes and risks were compared by age among patients 50 years or older after a hospitalization for ACS. Data were collected from October 26, 2005, through July 8, 2010, with the database locked October 21, 2014. Data were analyzed May 29, 2015, through March 13, 2018, using Kaplan-Meier curves and Cox proportional hazards models. Interventions: Double-blind randomized assignment to combined simvastatin and ezetimibe or simvastatin and placebo with follow-up for a median of 6 years (interquartile range, 4.3-7.1 years). Main Outcomes and Measures: The primary composite end point consisted of death due to cardiovascular disease, myocardial infarction (MI), stroke, unstable angina requiring hospitalization, and coronary revascularization after 30 days. Individual adverse ischemic and safety end points and lipid variables were also analyzed. Results: Of 18 144 patients enrolled (13 728 men [75.7%]; mean [SD] age, 64.1 [9.8] years), 5173 (28.5%) were 65 to 74 years old, and 2798 (15.4%) were 75 years or older at randomization. Treatment with simvastatin-ezetimibe resulted in lower rates of the primary end point than simvastatin-placebo, including 0.9% for patients younger than 65 years (HR, 0.97; 95% CI, 0.90-1.05) and 0.8% for patients 65 to 74 years of age (hazard ratio [HR], 0.96; 95% CI, 0.87-1.06), with the greatest absolute risk reduction of 8.7% for patients 75 years or older (HR, 0.80; 95% CI, 0.70-0.90) (P = .02 for interaction). The rate of adverse events did not increase with simvastatin-ezetimibe vs simvastatin-placebo among younger or older patients. Conclusions and Relevance: In IMPROVE-IT, patients hospitalized for ACS derived benefit from higher-intensity therapy to lower lipid levels with simvastatin-ezetimibe compared with simvastatin monotherapy, with the greatest absolute risk reduction among patients 75 years or older. Addition of ezetimibe to simvastatin was not associated with any significant increase in safety issues among older patients. These results may have implications for guideline recommendations regarding lowering of lipid levels in the elderly. Trial Registration: ClinicalTrials.gov identifier: NCT00202878.


Asunto(s)
Síndrome Coronario Agudo/sangre , Combinación Ezetimiba y Simvastatina/uso terapéutico , Hipolipemiantes/uso terapéutico , Lípidos/sangre , Simvastatina/uso terapéutico , Factores de Edad , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
20.
Circ Cardiovasc Qual Outcomes ; 12(1): e005041, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30630361

RESUMEN

BACKGROUND: Although cholesterol-lowering medications can reduce the risk of recurrent cardiovascular events, premature discontinuation limits effectiveness. Discontinuation rates have not been systematically reported for lipid-lowering trials. METHODS AND RESULTS: We evaluated medication discontinuation in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial), which evaluated placebo+simvastatin versus ezetimibe+simvastatin in patients hospitalized with the acute coronary syndrome and followed longitudinally postdischarge. Reasons for discontinuation were evaluated from randomization through study end (median 71.9 [interquartile range 51.8-85.8] months). Kaplan-Meier (KM) discontinuation rates were evaluated at 30 days, 1 year, and through year 7, and compared by treatment arm and region, with Cox proportional hazards modeling used to evaluate predictors of discontinuation. Overall, 46.7% of subjects discontinued study medication (KM rate by study end 50.9% [95% CI, 50.1%-51.7%]). The risk of discontinuation was highest early in the trial but decreased with increasing time, with a terminal KM rate per 100 person-years of 8.4 (8.2-8.6) from years 1 to 7. Discontinuation was higher in the placebo+simvastatin versus ezetimibe+simvastatin arm (KM rate 52.0% versus 49.8%, P=0.049) and was highest in the United States (7-year KM rate 57.4%). In multivariable modeling, smoking, prior revascularization, hypertension, unstable angina, female sex, nonwhite race, and US location were associated with higher discontinuation rates. CONCLUSIONS: Although discontinuation was highest early and stabilized to 8% per year, because of prolonged follow-up, most discontinuation occurred after year 1. Adding ezetimibe to statin therapy did not increase discontinuation risk. Geographic differences and patient-level factors should be considered in trial design and analysis. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00202878.


Asunto(s)
Síndrome Coronario Agudo/tratamiento farmacológico , Dislipidemias/tratamiento farmacológico , Combinación Ezetimiba y Simvastatina/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Lípidos/sangre , Pautas de la Práctica en Medicina/tendencias , Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/epidemiología , Anciano , Asia/epidemiología , Australia/epidemiología , Biomarcadores/sangre , Método Doble Ciego , Esquema de Medicación , Utilización de Medicamentos/tendencias , Dislipidemias/sangre , Dislipidemias/epidemiología , Europa (Continente)/epidemiología , Combinación Ezetimiba y Simvastatina/efectos adversos , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , América del Norte/epidemiología , Factores de Riesgo , América del Sur/epidemiología , Factores de Tiempo , Resultado del Tratamiento
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