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1.
Genome Res ; 33(6): 857-871, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37217254

RESUMEN

The Diversity Outbred (DO) mice and their inbred founders are widely used models of human disease. However, although the genetic diversity of these mice has been well documented, their epigenetic diversity has not. Epigenetic modifications, such as histone modifications and DNA methylation, are important regulators of gene expression and, as such, are a critical mechanistic link between genotype and phenotype. Therefore, creating a map of epigenetic modifications in the DO mice and their founders is an important step toward understanding mechanisms of gene regulation and the link to disease in this widely used resource. To this end, we performed a strain survey of epigenetic modifications in hepatocytes of the DO founders. We surveyed four histone modifications (H3K4me1, H3K4me3, H3K27me3, and H3K27ac), as well as DNA methylation. We used ChromHMM to identify 14 chromatin states, each of which represents a distinct combination of the four histone modifications. We found that the epigenetic landscape is highly variable across the DO founders and is associated with variation in gene expression across strains. We found that epigenetic state imputed into a population of DO mice recapitulated the association with gene expression seen in the founders, suggesting that both histone modifications and DNA methylation are highly heritable mechanisms of gene expression regulation. We illustrate how DO gene expression can be aligned with inbred epigenetic states to identify putative cis-regulatory regions. Finally, we provide a data resource that documents strain-specific variation in the chromatin state and DNA methylation in hepatocytes across nine widely used strains of laboratory mice.


Asunto(s)
Metilación de ADN , Histonas , Humanos , Ratones , Animales , Histonas/genética , Histonas/metabolismo , Regiones Promotoras Genéticas , Cromatina/genética , Epigénesis Genética , Código de Histonas , Ratones Endogámicos , Expresión Génica
2.
Nucleic Acids Res ; 51(11): 5364-5376, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-36951113

RESUMEN

The human genome contains about 800 C2H2 zinc finger proteins (ZFPs), and most of them are composed of long arrays of zinc fingers. Standard ZFP recognition model asserts longer finger arrays should recognize longer DNA-binding sites. However, recent experimental efforts to identify in vivo ZFP binding sites contradict this assumption, with many exhibiting short motifs. Here we use ZFY, CTCF, ZIM3, and ZNF343 as examples to address three closely related questions: What are the reasons that impede current motif discovery methods? What are the functions of those seemingly unused fingers and how can we improve the motif discovery algorithms based on long ZFPs' biophysical properties? Using ZFY, we employed a variety of methods and find evidence for 'dependent recognition' where downstream fingers can recognize some previously undiscovered motifs only in the presence of an intact core site. For CTCF, high-throughput measurements revealed its upstream specificity profile depends on the strength of its core. Moreover, the binding strength of the upstream site modulates CTCF's sensitivity to different epigenetic modifications within the core, providing new insight into how the previously identified intellectual disability-causing and cancer-related mutant R567W disrupts upstream recognition and deregulates the epigenetic control by CTCF. Our results establish that, because of irregular motif structures, variable spacing and dependent recognition between sub-motifs, the specificities of long ZFPs are significantly underestimated, so we developed an algorithm, ModeMap, to infer the motifs and recognition models of ZIM3 and ZNF343, which facilitates high-confidence identification of specific binding sites, including repeats-derived elements. With revised concept, technique, and algorithm, we can discover the overlooked specificities and functions of those 'extra' fingers, and therefore decipher their broader roles in human biology and diseases.


Asunto(s)
ADN , Factores de Transcripción , Dedos de Zinc , Humanos , Sitios de Unión , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Algoritmos , Motivos de Nucleótidos , Secuencias de Aminoácidos , ADN/química , ADN/metabolismo
3.
J Am Soc Nephrol ; 35(3): 311-320, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38261535

RESUMEN

SIGNIFICANCE STATEMENT: Metabolic acidosis is a common complication of CKD and is associated with more rapid decline of kidney function, but well-powered controlled randomized trials testing the effect of treating metabolic acidosis on slowing CKD progression have not been conducted. The VALOR-CKD study randomized 1480 individuals with CKD and metabolic acidosis, across 320 sites to placebo or veverimer (a novel hydrochloric acid binder). The findings did not demonstrate the efficacy of veverimer in slowing CKD progression, but the difference in serum bicarbonate between placebo and drug arms was only approximately 1 mEq/L. Veverimer was safe and well tolerated. BACKGROUND: Metabolic acidosis is common in CKD, but whether its treatment slows CKD progression is unknown. Veverimer, a novel hydrochloric acid binder that removes acid from the gastrointestinal tract, leads to an increase in serum bicarbonate. METHODS: In a phase 3, double-blind, placebo-controlled trial, patients with CKD (eGFR of 20-40 ml/min per 1.73 m 2 ) and metabolic acidosis (serum bicarbonate of 12-20 mEq/L) from 35 countries were randomized to veverimer or placebo. The primary outcome was the composite end point of CKD progression, defined as the development of ESKD (kidney transplantation or maintenance dialysis), a sustained decline in eGFR of ≥40% from baseline, or death due to kidney failure. RESULTS: The mean (±SD) baseline eGFR was 29.2±6.3 ml/min per 1.73 m 2 , and serum bicarbonate was 17.5±1.4 mEq/L; this increased to 23.4±2.0 mEq/L after the active treatment run-in. After randomized withdrawal, the mean serum bicarbonate was 22.0±3.0 mEq/L and 20.9±3.3 mEq/L in the veverimer and placebo groups at month 3, and this approximately 1 mEq/L difference remained stable for the first 24 months. A primary end point event occurred in 149/741 and 148/739 patients in the veverimer and placebo groups, respectively (hazard ratio, 0.99; 95% confidence interval, 0.8 to 1.2; P = 0.90). Serious and overall adverse event incidence did not differ between the groups. CONCLUSIONS: Among patients with CKD and metabolic acidosis, treatment with veverimer did not slow CKD progression. The lower than expected bicarbonate separation may have hindered the ability to test the hypothesis. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: VALOR-CKD, NCT03710291 .


Asunto(s)
Acidosis , Polímeros , Insuficiencia Renal Crónica , Humanos , Bicarbonatos/uso terapéutico , Ácido Clorhídrico , Acidosis/tratamiento farmacológico , Acidosis/etiología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico
4.
Chemistry ; 30(36): e202401462, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664199

RESUMEN

Since its first synthesis by Clar in 1948, terrylene - a fully connected ternaphthalene oligomer via naphthalene's peri-positions - has gained special focus within the rylene family, drawing interest for its unique chemical, structural, optoelectronic and single photon emission properties. In this study, we introduce a novel synthetic pathway that enhances the solubility of terrylene derivatives through complete peri-alkylation, while also facilitating extensions at the bay-positions. This approach not only broadens the scope of terrylene's chemical versatility but also opens new avenues for developing solution processable novel multi-edge nanographenes and tailoring electronic energy levels through topological edge structures. Our findings include a comprehensive structural and spectroscopic characterization along with transient absorption spectroscopy and photophysics of both the synthesized peri-alkylated terrylene and its phenylene-fused derivative.

5.
Ann Bot ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477369

RESUMEN

BACKGROUND AND AIMS: Many agricultural areas are expected to face hotter, drier conditions from climate change. Understanding the mechanisms crops use to mitigate these stresses can guide breeding for more tolerant plant material. We tested relationships between traits, physiological function under hot conditions, and historical climate associations to evaluate these mechanisms for winegrapes. We expected a more negative leaf osmotic potential at full hydration (πo), which reduces leaf turgor loss during drought, and either a metabolically cheaper or more osmoprotectant leaf chemical composition, to allow cultivars associated with hot, dry regions to maintain greater gas exchange under hot growing conditions. METHODS: We measured πo, gas exchange, and leaf chemistry for 7 commercially important winegrape cultivars that vary widely in historical climate associations. Vines were grown under common garden field conditions in a hot wine-growing region (Davis, California) and measured over the hottest period of the growing season (July - September). KEY RESULTS: □o varied significantly between cultivars, and all cultivars significantly reduced □o (osmotically adjusted) over the study period, though osmotic adjustment did not vary across cultivars. πo was correlated with gas exchange and climate associations, but in the opposite directions than expected. Photosynthesis and πo were higher in the cultivars associated with hotter, less humid regions. Leaf chemical composition varied between cultivars, but was not related to climate associations. CONCLUSIONS: These findings suggest that leaf turgor maintenance is not a primary limitation on grapevine adaptation to hot or atmospherically dry growing conditions. Thus, selecting for a more negative πo or greater osmotic adjustment is not a promising strategy to develop more climate-resilient grape varieties, contrary to findings for other crops. Future work is needed to identify the mechanisms increasing photosynthesis in the cultivars associated with hot, dry regions.

6.
Retina ; 44(3): 487-497, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37972955

RESUMEN

PURPOSE: The LIGHTSITE III study evaluated multiwavelength photobiomodulation (PBM) therapy in nonexudative (dry) age-related macular degeneration (AMD) using the LumiThera Valeda Light Delivery System. METHODS: LIGHTSITE III is a randomized, controlled trial to assess the safety and effectiveness of PBM in dry AMD. Subjects were given multiwavelength PBM (590, 660, and 850 nm) or Sham treatment delivered in a series of nine sessions over 3 to 5 weeks every four months over 24 months. Subjects were assessed for efficacy and safety outcomes. Data from the 13-month analysis are presented in this report. RESULTS: A total of 100 subjects (148 eyes) with dry AMD were randomized. LIGHTSITE III met the primary efficacy best-corrected visual acuity endpoint with a significant difference between PBM (n = 91 eyes) and Sham (n = 54 eyes) groups (Between group difference: 2.4 letters (SE 1.15), CI: -4.7 to -0.1, P = 0.02) (PBM alone: 5.4 letters (SE 0.96), CI: 3.5 to 7.3, P < 0.0001; Sham alone: 3.0 letters (SE 1.13), CI: 0.7-5.2, P < 0.0001). The PBM group showed a significant decrease in new onset geographic atrophy ( P = 0.024, Fisher exact test, odds ratio 9.4). A favorable safety profile was observed. CONCLUSION: LIGHTSITE III provides a prospective, randomized, controlled trial showing improved clinical and anatomical outcomes in intermediate dry AMD following PBM therapy.


Asunto(s)
Atrofia Geográfica , Terapia por Luz de Baja Intensidad , Degeneración Macular , Humanos , Estudios Prospectivos , Agudeza Visual , Degeneración Macular/diagnóstico , Degeneración Macular/radioterapia , Degeneración Macular/tratamiento farmacológico , Ojo , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/radioterapia
7.
J Exp Child Psychol ; 239: 105826, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38118379

RESUMEN

Imitation that entails faithful reproduction of demonstrated behavior by reenacting a sequence of actions accurately is a fast and efficient way to acquire new skills as well as to conform to social norms. Previous studies reported that both culture and gender might impinge on young children's fidelity of imitation. We analyzed the imitative behavior of 87 children whose ages ranged from 3 to 6 years. An instrumental task was administered that offered partial (opaque apparatus) or total (transparent apparatus) information about causal connection between the demonstrated actions and their effect in achieving a desired reward. Imitative fidelity (imitating the actions that were demonstrated by an adult model yet were unnecessary for achieving the instrumental goal) increased as a function of age in boys, whereas no differences were found in girls. This lack of increase in girls can be ascribed to their displaying higher degrees of imitation fidelity at an earlier age.


Asunto(s)
Conducta Imitativa , Motivación , Masculino , Niño , Femenino , Humanos , Preescolar , Normas Sociales
8.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33790017

RESUMEN

Estimating the impact of child health investments on adult living standards entails multiple methodological challenges, including the lack of experimental variation in health status, an inability to track individuals over time, and accurately measuring living standards and productivity in low-income settings. This study exploits a randomized school health intervention that provided deworming treatment to Kenyan children, and uses longitudinal data to estimate impacts on economic outcomes up to 20 y later. The effective respondent tracking rate was 84%. Individuals who received two to three additional years of childhood deworming experienced a 14% gain in consumption expenditures and 13% increase in hourly earnings. There are also shifts in sectors of residence and employment: treatment group individuals are 9% more likely to live in urban areas, and experience a 9% increase in nonagricultural work hours. Most effects are concentrated among males and older individuals. The observed consumption and earnings benefits, together with deworming's low cost when distributed at scale, imply that a conservative estimate of its annualized social internal rate of return is 37%, a high return by any standard.


Asunto(s)
Antihelmínticos/uso terapéutico , Costo de Enfermedad , Helmintiasis/prevención & control , Adolescente , Adulto , Antihelmínticos/administración & dosificación , Antihelmínticos/economía , Niño , Salud Infantil/economía , Salud Infantil/tendencias , Utilización de Medicamentos/tendencias , Empleo/tendencias , Helmintiasis/tratamiento farmacológico , Helmintiasis/economía , Helmintiasis/epidemiología , Humanos , Renta/tendencias , Kenia
9.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33972424

RESUMEN

The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease.


Asunto(s)
Evolución Biológica , Ecología/métodos , Hominidae/microbiología , Metagenoma/genética , Microbiota/genética , Boca/microbiología , África , Animales , Bacterias/clasificación , Bacterias/genética , Biopelículas , Placa Dental/microbiología , Geografía , Gorilla gorilla/microbiología , Hominidae/clasificación , Humanos , Pan troglodytes/microbiología , Filogenia
10.
PLoS Med ; 20(4): e1004081, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37023021

RESUMEN

BACKGROUND: The Coronavirus Disease 2019 (COVID-19) pandemic and associated mitigation policies created a global economic and health crisis of unprecedented depth and scale, raising the estimated prevalence of depression by more than a quarter in high-income countries. Low- and middle-income countries (LMICs) suffered the negative effects on living standards the most severely. However, the consequences of the pandemic for mental health in LMICs have received less attention. Therefore, this study assesses the association between the COVID-19 crisis and mental health in 8 LMICs. METHODS AND FINDINGS: We conducted a prospective cohort study to examine the correlation between the COVID-19 pandemic and mental health in 10 populations from 8 LMICs in Asia, Africa, and South America. The analysis included 21,162 individuals (mean age 38.01 years, 64% female) who were interviewed at least once pre- as well as post-pandemic. The total number of survey waves ranged from 2 to 17 (mean 7.1). Our individual-level primary outcome measure was based on validated screening tools for depression and a weighted index of depression questions, dependent on the sample. Sample-specific estimates and 95% confidence intervals (CIs) for the association between COVID-19 periods and mental health were estimated using linear regressions with individual fixed effects, controlling for independent time trends and seasonal variation in mental health where possible. In addition, a regression discontinuity design was used for the samples with multiple surveys conducted just before and after the onset of the pandemic. We aggregated sample-specific coefficients using a random-effects model, distinguishing between estimates for the short (0 to 4 months) and longer term (4+ months). The random-effects aggregation showed that depression symptoms are associated with a increase by 0.29 standard deviations (SDs) (95% CI [-.47, -.11], p-value = 0.002) in the 4 months following the onset of the pandemic. This change was equivalent to moving from the 50th to the 63rd percentile in our median sample. Although aggregate depression is correlated with a decline to 0.21 SD (95% CI [-0.07, -.34], p-value = 0.003) in the period thereafter, the average recovery of 0.07 SD (95% CI [-0.09, .22], p-value = 0.41) was not statistically significant. The observed trends were consistent across countries and robust to alternative specifications. Two limitations of our study are that not all samples are representative of the national population, and the mental health measures differ across samples. CONCLUSIONS: Controlling for seasonality, we documented a large, significant, negative association of the pandemic on mental health, especially during the early months of lockdown. The magnitude is comparable (but opposite) to the effects of cash transfers and multifaceted antipoverty programs on mental health in LMICs. Absent policy interventions, the pandemic could be associated with a lasting legacy of depression, particularly in settings with limited mental health support services, such as in many LMICs. We also demonstrated that mental health fluctuates with agricultural crop cycles, deteriorating during "lean", pre-harvest periods and recovering thereafter. Ignoring such seasonal variations in mental health may lead to unreliable inferences about the association between the pandemic and mental health.


Asunto(s)
COVID-19 , Humanos , Femenino , Adulto , Masculino , COVID-19/epidemiología , Países en Desarrollo , Salud Mental , Pandemias , Estudios Prospectivos , Control de Enfermedades Transmisibles
11.
Lancet ; 400(10364): 1704-1711, 2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36366886

RESUMEN

BACKGROUND: Vasomotor symptoms (hot flushes and night sweats) are experienced by more than two-thirds of women with breast cancer taking oral adjuvant endocrine therapy. Safe and effective treatments are lacking. Q-122 is a novel, non-hormonal compound that has shown promise for reducing vasomotor symptoms by modulation of oestrogen-responsive neurons in the hypothalamus. We aimed to assess the efficacy and safety of Q-122 in women with breast cancer taking oral adjuvant endocrine therapy and experiencing vasomotor symptoms. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled, proof-of-concept, phase 2 trial at 18 sites in Australia, New Zealand, and the USA. Eligible participants were women, aged 18-70 years, taking a stable dose of tamoxifen or an aromatase inhibitor following breast cancer and experiencing at least 50 self-reported moderate to severe vasomotor symptoms per week. Participants were randomly assigned (1:1) using an interactive web response system to oral Q-122 100 mg or identical placebo, twice daily for 28 days. Randomisation was stratified by BMI (≤30 kg/m2 or >30 kg/m2) and use of any of a selective serotonin reuptake inhibitor, selective norepinephrine reuptake inhibitor, gabapentin, or pregabalin. Q-122 and placebo capsules were identical in appearance and containers identically labelled. During the double-blind treatment and analysis phases, the participants, investigators, clinical research organisation staff, and sponsor were masked to treatment allocation. The primary outcome was the difference in the mean percentage change from baseline in the Vasomotor Symptom Severity Score of moderate and severe hot flushes and night sweats (msVMS-SS) between Q-122 and placebo after 28 days of treatment. Primary analysis was by modified intention-to-treat and safety was assessed in all participants receiving at least one dose of study drug. This study is registered at ClinicalTrials.gov, NCT03518138. FINDINGS: Between Oct 24, 2018, and Sept 9, 2020, 243 patients were screened, 131 of whom were randomly assigned and received treatment (Q-122 n=65 and placebo n=66). Q-122 resulted in a significantly greater mean percentage change in msVMS-SS from baseline over 28 days of treatment compared with placebo (least squares mean: Q-122 -39% [95% CI -46 to -31] vs placebo -26% [-33 to -18]; p=0·018). Treatment-emergent adverse events were generally mild to moderate and similar between the two groups (treatment-related treatment-emergent adverse events in 11 [17%] of 65 patients in the Q-122 group vs nine [14%] of 66 in the placebo group); zero patients in the Q-122 group and two (3%) patients in the placebo group had serious adverse events. INTERPRETATION: Q-122 is an effective and well tolerated non-hormonal oral treatment for vasomotor symptoms in women taking oral adjuvant endocrine therapy after breast cancer. Our results support the conduct of larger and longer studies of Q-122, with potential use extending to postmenopausal women who require an alternative to menopausal hormone therapy. FUNDING: QUE Oncology.


Asunto(s)
Inhibidores de la Aromatasa , Neoplasias de la Mama , Humanos , Femenino , Masculino , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Tamoxifeno/efectos adversos , Método Doble Ciego , Resultado del Tratamiento , Sofocos/inducido químicamente , Sofocos/tratamiento farmacológico
12.
Nat Immunol ; 12(3): 239-46, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21278735

RESUMEN

Colonic homeostasis entails epithelium-lymphocyte cooperation, yet many participants in this process are unknown. We show here that epithelial microRNAs mediate the mucosa-immune system crosstalk necessary for mounting protective T helper type 2 (T(H)2) responses. Abolishing the induction of microRNA by gut-specific deletion of Dicer1 (Dicer1(Δgut)), which encodes an enzyme involved in microRNA biogenesis, deprived goblet cells of RELMß, a key T(H)2 antiparasitic cytokine; this predisposed the host to parasite infection. Infection of Dicer1(Δgut) mice with helminths favored a futile T(H)1 response with hallmarks of inflammatory bowel disease. Interleukin 13 (IL-13) induced the microRNA miR-375, which regulates the expression of TSLP, a T(H)2-facilitating epithelial cytokine; this indicated a T(H)2-amplification loop. We found that miR-375 was required for RELMß expression in vivo; miR-375-deficient mice had significantly less intestinal RELMß, which possibly explains the greater susceptibility of Dicer1(Δgut) mice to parasites. Our findings indicate that epithelial microRNAs are key regulators of gut homeostasis and mucosal immunity.


Asunto(s)
Inmunidad Mucosa/inmunología , MicroARNs/inmunología , Linfocitos T/inmunología , Animales , Comunicación Celular , Epitelio/inmunología , Tracto Gastrointestinal/inmunología , Células HT29 , Humanos , Inmunohistoquímica , Interleucina-13/metabolismo , Ratones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal
13.
Nephrol Dial Transplant ; 38(6): 1448-1458, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-36331426

RESUMEN

BACKGROUND: Whether treating metabolic acidosis slows progression of chronic kidney disease (CKD) has not been established. Veverimer is a novel hydrochloric acid binder that removes acid from the gastrointestinal tract leading to an increase in serum bicarbonate; it is being developed to treat metabolic acidosis with the goal of slowing progression of CKD. METHODS: The VALOR-CKD trial is an international, randomized, multicenter, double-blind, placebo-controlled study designed to evaluate the effect of once-daily veverimer on kidney disease progression in patients with metabolic acidosis and CKD. Eligibility criteria include a serum bicarbonate in the range of 12-20 mmol/L and an estimated glomerular filtration rate (eGFR) of 20-40 mL/min/1.73 m2. The primary outcome is kidney disease progression defined as the development of end-stage kidney disease, a sustained decline in eGFR of >40% from baseline or death due to kidney failure. Key secondary endpoints include effects on physical function. RESULTS: Between December 2018 and December 2021, 1480 participants were randomized. The mean age at baseline was 65.1 years and 42% of the patients were female. The mean baseline eGFR was 29.1 mL/min/1.73 m2 and mean serum bicarbonate was 17.5 mmol/L. The median urine albumin-to-creatinine ratio at screening was 201 mg/g and the median 5-year predicted risk of kidney failure was 32%. Diabetes and hypertension were present in 56% and 98% of participants, respectively. CONCLUSIONS: VALOR-CKD has recruited a large population of people with metabolic acidosis at high risk for CKD progression to determine the effects of veverimer on the risk of progressive loss of kidney function.


Asunto(s)
Acidosis , Insuficiencia Renal Crónica , Humanos , Femenino , Masculino , Bicarbonatos/uso terapéutico , Acidosis/tratamiento farmacológico , Acidosis/etiología , Tasa de Filtración Glomerular , Método Doble Ciego , Progresión de la Enfermedad
14.
Inorg Chem ; 62(18): 6882-6892, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36715366

RESUMEN

At low guest atom concentrations, Si clathrates can be viewed as semiconductors, with the guest atoms acting as dopants, potentially creating alternatives to diamond Si with exciting optoelectronic and spin properties. Studying Si clathrates with different guest atoms would not only provide insights into the electronic structure of the Si clathrates but also give insights into the unique properties that each guest can bring to the Si clathrate structure. However, the synthesis of Si clathrates with guests other than Na is challenging. In this study, we have developed an alternative approach, using thermal diffusion into type II Si clathrate with an extremely low Na concentration, to create Si clathrate with Li guests. Using time-of-flight secondary-ion mass spectroscopy, X-ray diffraction, and Raman scattering, thermal diffusion of Li into the nearly empty Si clathrate framework is detected and characterized as a function of the diffusion temperature and time. Interestingly, the Si clathrate exhibits reduced structural stability in the presence of Li, converting to polycrystalline or disordered phases for anneals at temperatures where the starting Na guest Si clathrate is quite stable. The Li atoms inserted into the Si clathrate lattice contribute free carriers, which can be detected in Raman scattering through their effect on the strength of Si-Si bonds in the framework. These carriers can also be observed in electron paramagnetic resonance (EPR). EPR shows, however, that Li guests are not simple analogues of Na guests. In particular, our results suggest that Li atoms, with their smaller size, tend to doubly occupy cages, forming "molecular-like" pairs with other Li or Na atoms. Results of this work provide a deeper insight into Li guest atoms in Si clathrate. These findings are also relevant to understanding how Li moves through and interacts with Si clathrate anodes in Li-ion batteries. Additionally, techniques presented in this work demonstrate a new method for filling the Si clathrate cages, enabling studies of a broad range of other guests in Si clathrates.

15.
Compr Rev Food Sci Food Saf ; 22(5): 3984-4003, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37530543

RESUMEN

Food allergy remains a public health, business, and regulatory challenge. Risk analysis (RA) and risk management (RM) of food allergens are of great importance and analysis for food allergens is necessary for both. The current workhorse techniques for allergen analysis (enzyme linked immunosorbent assay [ELISA] and real-time polymerase chain reaction) exhibit recognized challenges including variable and antibody specific responses and detection of species DNA rather than allergen protein, respectively. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) enables protein identification, with potential for multiplex analysis and traceability to the System of International units (SI), aiding global measurement standardization. In this review, recent literature has been systematically reviewed to assess progress in LC-MS/MS and define the potential and benefits of matrix-assisted laser desorption/ionization-time-of-flight MS (MALDI-ToF-MS) technology for allergen analysis. MALDI-ToF-MS of initially intact protein is already applied to verify in silico-derived peptide sequences for LC-MS/MS analysis. We describe the origins of MALDI and its future perspectives, including affinity bead-assisted assays coupled to MALDI. Based on the proliferation of reliable and reproducible MALDI-based clinical applications, the technique should emulate the detection capability (sensitivity) of established allergen detection techniques, whilst reducing technical support and having equivalent multiplexing potential to competing techniques, for example, LC-MS/MS and ELISA. Although unlikely to offer inherent SI traceability, MALDI-based allergen analysis will complement existing MS approaches for allergens. Affinity bead-MALDI appears capable of higher throughput at lower cost per sample than almost any existing technique, enabling repeated sub-sampling as a way to reduce representative sampling issues.


Asunto(s)
Proteínas , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masas en Tándem/métodos , Alérgenos/análisis , Rayos Láser
16.
Sex Transm Dis ; 49(8): 534-540, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35608079

RESUMEN

BACKGROUND: The rollout of preexposure prophylaxis (PrEP) for HIV prevention among gay and bisexual men (GBM) is associated with increases in condomless anal intercourse, potentially increasing the incidence of other sexually transmissible infections (STIs). METHODS: We developed an individual-based mathematical model to simulate the transmission of Neisseria gonorrhoeae among GBM in Sydney, accounting for changes in sexual practices, STI testing, and PrEP use. We calibrated and validated the model using reported incidence rates for HIV-positive and HIV-negative GBM from 2010 to 2019. Scenarios were run with varying PrEP uptake, PrEP-related STI testing, and PrEP-related sexual behavior and testing intervals up to 2030 to assess the impact of PrEP use on gonorrhea incidence. RESULTS: Preexposure prophylaxis uptake and associated 3-monthly STI testing from 2015 onward resulted in a predicted increase from 20 to 37 N. gonorrhoeae infections per 100 person-years among HIV-negative GBM by the end of 2020. This is lower than the counterfactual predictions of 45 per 100 person-years if PrEP were not scaled up and 48 per 100 person-years with nonadherence to 3-monthly STI testing. Increasing the time between STI tests for PrEP users by 1 month from 2018 results in the incidence rate among HIV-negative GBM increasing by 8% by 2030. If PrEP coverage doubles from 24% to 53%, incidence among HIV-negative GBM declines by ~25% by 2030. CONCLUSIONS: Behavior change due to widespread PrEP use may lead to significant increases in gonorrhea incidence in GBM, but the recommended quarterly STI testing recommended for PrEP users should reduce incidence by 18% by 2030.


Asunto(s)
Gonorrea , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Gonorrea/epidemiología , Gonorrea/prevención & control , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Incidencia , Masculino , Modelos Teóricos , Profilaxis Pre-Exposición/métodos , Conducta Sexual
17.
PLoS Pathog ; 15(1): e1007164, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30703164

RESUMEN

With relatively few known specific transcription factors to control the abundance of specific mRNAs, Plasmodium parasites may rely more on the regulation of transcript stability and turnover to provide sufficient gene regulation. Plasmodium transmission stages impose translational repression on specific transcripts in part to accomplish this. However, few proteins are known to participate in this process, and those that are characterized primarily affect female gametocytes. We have identified and characterized Plasmodium yoelii (Py) CCR4-1, a putative deadenylase, which plays a role in the development and activation of male gametocytes, regulates the abundance of specific mRNAs in gametocytes, and ultimately increases the efficiency of host-to-vector transmission. We find that when pyccr4-1 is deleted or its protein made catalytically inactive, there is a loss in the initial coordination of male gametocyte maturation and a reduction of parasite infectivity of the mosquito. Expression of only the N-terminal CAF1 domain of the essential CAF1 deadenylase leads to a similar phenotype. Comparative RNA-seq revealed that PyCCR4-1 affects transcripts important for transmission-related functions that are associated with male or female gametocytes, some of which directly associate with the immunoprecipitated complex. Finally, circular RT-PCR of one of the bound, dysregulated transcripts showed that deletion of the pyccr4-1 gene does not result in gross changes to its UTR or poly(A) tail length. We conclude that the two putative deadenylases of the CAF1/CCR4/NOT complex play critical and intertwined roles in gametocyte maturation and transmission.


Asunto(s)
Plasmodium falciparum/genética , Receptores CCR4/metabolismo , Animales , Culicidae/metabolismo , Exorribonucleasas , Gametogénesis/fisiología , Regulación de la Expresión Génica , Proteínas de Homeodominio , Masculino , Ratones , Mosquitos Vectores , Plasmodium/genética , Plasmodium falciparum/metabolismo , Proteínas , ARN Mensajero/genética , Proteínas Represoras , Ribonucleasas , Factores de Transcripción/metabolismo , Activación Transcripcional
18.
Clin Exp Allergy ; 51(10): 1322-1330, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34233055

RESUMEN

INTRODUCTION: Food hypersensitivity (FHS), including food allergy, coeliac disease and food intolerance, is a major public health issue. The Food Standards Agency (FSA), an independent UK Government department working to protect public health and consumers' wider interests in food, sought to identify research priorities in the area of FHS. METHODS: A priority setting exercise was undertaken, using a methodology adapted from the James Lind Alliance-the first such exercise with respect to food hypersensitivity. A UK-wide public consultation was held to identify unanswered research questions. After excluding diagnostics, desensitization treatment and other questions which were out of scope for FSA or where FSA was already commissioning research, 15 indicative questions were identified and prioritized by a range of stakeholders, representing food businesses, patient groups, health care and academia, local authorities and the FSA. RESULTS: 295 responses were received during the public consultation, which were categorized into 70 sub-questions and used to define 15 key evidence uncertainties ('indicative questions') for prioritization. Using the JLA prioritization framework, this resulted in 10 priority uncertainties in evidence, from which 16 research questions were developed. These could be summarized under the following 5 themes: communication of allergens both within the food supply chain and then to the end consumer (ensuring trust in allergen communication); the impact of socio-economic factors on consumers with FHS; drivers of severe reactions; mechanism(s) underlying loss of tolerance in FHS; and the risks posed by novel allergens/processing. DISCUSSION: In this first research prioritization exercise for food allergy and FHS, key priorities identified to protect the food-allergic public were strategies to help allergic consumers to make confident food choices, prevention of FHS and increasing understanding of socio-economic impacts. Diagnosis and treatment of FHS was not considered in this prioritization.


Asunto(s)
Investigación Biomédica , Hipersensibilidad a los Alimentos , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/prevención & control , Humanos , Reino Unido/epidemiología
19.
Environ Sci Technol ; 55(15): 10255-10267, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34270218

RESUMEN

Detailed offline speciation of gas- and particle-phase organic compounds was conducted using gas/liquid chromatography with traditional and high-resolution mass spectrometers in a hybrid targeted/nontargeted analysis. Observations were focused on an unoccupied home and were compared to two other indoor sites. Observed gas-phase organic compounds span the volatile to semivolatile range, while functionalized organic aerosols extend from intermediate volatility to ultra-low volatility, including a mix of oxygen, nitrogen, and sulfur-containing species. Total gas-phase abundances of hydrocarbon and oxygenated gas-phase complex mixtures were elevated indoors and strongly correlated in the unoccupied home. While gas-phase concentrations of individual compounds generally decreased slightly with greater ventilation, their elevated ratios relative to controlled emissions of tracer species suggest that the dilution of gas-phase concentrations increases off-gassing from surfaces and other indoor reservoirs, with volatility-dependent responses to dynamically changing environmental factors. Indoor-outdoor emissions of gas-phase intermediate-volatility/semivolatile organic hydrocarbons from the unoccupied home averaged 6-11 mg h-1, doubling with ventilation. While the largest single-compound emissions observed were furfural (61-275 mg h-1) and acetic acid, observations spanned a wide range of individual volatile chemical products (e.g., terpenoids, glycol ethers, phthalates, other oxygenates), highlighting the abundance of long-lived reservoirs resulting from prior indoor use or materials, and their gradual transport outdoors.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Compuestos Orgánicos Volátiles , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Compuestos Orgánicos Volátiles/análisis
20.
Indoor Air ; 31(4): 1199-1216, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33484190

RESUMEN

Reactive oxygen species (ROS) are an important contributor to adverse health effects associated with ambient air pollution. Despite infiltration of ROS from outdoors, and possible indoor sources (eg, combustion), there are limited data available on indoor ROS. In this study, part of the second phase of Air Composition and Reactivity from Outdoor aNd Indoor Mixing campaign (ACRONIM-2), we constructed and deployed an online, continuous, system to measure extracellular gas- and particle-phase ROS during summer in an unoccupied residence in St. Louis, MO, USA. Over a period of one week, we observed that the non-denuded outdoor ROS (representing particle-phase ROS and some gas-phase ROS) concentration ranged from 1 to 4 nmol/m3 (as H2 O2 ). Outdoor concentrations were highest in the afternoon, coincident with peak photochemistry periods. The indoor concentrations of particle-phase ROS were nearly equal to outdoor concentrations, regardless of window-opening status or air exchange rates. The indoor/outdoor ratio of non-denuded ROS (I/OROS ) was significantly less than 1 with windows open and even lower with windows closed. Combined, these observations suggest that gas-phase ROS are efficiently removed by interior building surfaces and that there may be an indoor source of particle-phase ROS.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Tamaño de la Partícula , Material Particulado/análisis , Especies Reactivas de Oxígeno/análisis
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