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1.
Proc Natl Acad Sci U S A ; 121(31): e2400525121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39042683

RESUMO

Per- and polyfluoroalkyl substances (PFAS), particularly the perfluorinated ones, are recalcitrant to biodegradation. By integrating an enrichment culture of reductive defluorination with biocompatible electrodes for the electrochemical process, a deeper defluorination of a C6-perfluorinated unsaturated PFAS was achieved compared to the biological or electrochemical system alone. Two synergies in the bioelectrochemical system were identified: i) The in-series microbial-electrochemical defluorination and ii) the electrochemically enabled microbial defluorination of intermediates. These synergies at the material-microbe interfaces surpassed the limitation of microbial defluorination and further turned the biotransformation end products into less fluorinated products, which could be less toxic and more biodegradable in the environment. This material-microbe hybrid system brings opportunities in the bioremediation of PFAS driven by renewable electricity and warrants future research on mechanistic understanding of defluorinating and electroactive microorganisms at the material-microbe interface for system optimizations.


Assuntos
Biodegradação Ambiental , Anaerobiose , Halogenação , Eletrodos/microbiologia , Fluorocarbonos/metabolismo , Fluorocarbonos/química , Técnicas Eletroquímicas/métodos , Bactérias/metabolismo
2.
Trends Biochem Sci ; 47(9): 745-758, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35577675

RESUMO

The circadian clock is an intracellular timekeeping device that drives daily rhythms in diverse and extensive processes throughout the body. The clock mechanism comprises a core transcription/translation negative feedback loop that is modulated by a complex set of additional interlocking feedback loops. Pharmacological manipulation of the clock may be valuable for treating many maladies including jet lag, shift work and related sleep disorders, various metabolic diseases, and cancer. We review recent identification of small-molecule clock modulators and discuss the biochemical features of the core clock that may be amenable to future drug discovery.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Descoberta de Drogas
3.
Biostatistics ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39078115

RESUMO

Micro-randomized trials are commonly conducted for optimizing mobile health interventions such as push notifications for behavior change. In analyzing such trials, causal excursion effects are often of primary interest, and their estimation typically involves inverse probability weighting (IPW). However, in a micro-randomized trial, additional treatments can often occur during the time window over which an outcome is defined, and this can greatly inflate the variance of the causal effect estimator because IPW would involve a product of numerous weights. To reduce variance and improve estimation efficiency, we propose two new estimators using a modified version of IPW, which we call "per-decision IPW." The second estimator further improves efficiency using the projection idea from the semiparametric efficiency theory. These estimators are applicable when the outcome is binary and can be expressed as the maximum of a series of sub-outcomes defined over sub-intervals of time. We establish the estimators' consistency and asymptotic normality. Through simulation studies and real data applications, we demonstrate substantial efficiency improvement of the proposed estimator over existing estimators. The new estimators can be used to improve the precision of primary and secondary analyses for micro-randomized trials with binary outcomes.

4.
FASEB J ; 38(1): e23348, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38084798

RESUMO

A robust endogenous clock is required for proper function of many physiological processes. The suprachiasmatic nucleus (SCN) constitutes our central circadian clock and allows us to adapt to daily changes in the environment. Aging can cause a decline in the amplitude of circadian rhythms in SCN and peripheral clocks, which contributes to increased risk of several chronic diseases. Strengthening clock function would therefore be an effective strategy to improve health. A high-throughput chemical screening has identified clock-enhancing molecule 3 (CEM3) as small molecule that increases circadian rhythm amplitude in cell lines and SCN explants. It is, however, currently not known whether CEM3 acts by enhancing the amplitude of individual single-cell oscillators or by enhancing synchrony among neurons. In view of CEM3's potential, it is of evident importance to clarify the mode of action of CEM3. Here, we investigated the effects of CEM3 on single-cell PERIOD2::LUCIFERASE rhythms in mouse SCN explants. CEM3 increased the amplitude in approximately 80%-90% of the individual cells in the SCN without disrupting the phase and/or period of their rhythms. Noticeably, CEM3's effect on amplitude is independent of the cell's initial amplitude. These findings make CEM3 a potential therapeutic candidate to restore compromised amplitude in circadian rhythms and will boost the development of other molecular approaches to improve health.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Camundongos , Animais , Ritmo Circadiano/fisiologia , Núcleo Supraquiasmático/fisiologia , Relógios Circadianos/fisiologia , Luciferases/metabolismo , Neurônios/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35217617

RESUMO

Circadian clocks are timing systems that rhythmically adjust physiology and metabolism to the 24-h day-night cycle. Eukaryotic circadian clocks are based on transcriptional-translational feedback loops (TTFLs). Yet TTFL-core components such as Frequency (FRQ) in Neurospora and Periods (PERs) in animals are not conserved, leaving unclear how a 24-h period is measured on the molecular level. Here, we show that CK1 is sufficient to promote FRQ and mouse PER2 (mPER2) hyperphosphorylation on a circadian timescale by targeting a large number of low-affinity phosphorylation sites. Slow phosphorylation kinetics rely on site-specific recruitment of Casein Kinase 1 (CK1) and access of intrinsically disordered segments of FRQ or mPER2 to bound CK1 and on CK1 autoinhibition. Compromising CK1 activity and substrate binding affects the circadian clock in Neurospora and mammalian cells, respectively. We propose that CK1 and the clock proteins FRQ and PERs form functionally equivalent, phospho-based timing modules in the core of the circadian clocks of fungi and animals.


Assuntos
Proteínas CLOCK/metabolismo , Caseína Quinase I/metabolismo , Relógios Circadianos , Neurospora crassa/metabolismo , Animais , Cinética , Camundongos , Fosforilação
6.
J Infect Dis ; 229(4): 1158-1165, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38099506

RESUMO

BACKGROUND: Confounding introduced by individuals' sexual risk behavior is potentially a significant source of bias in HIV-1 prevention intervention studies. To more completely account for sexual behaviors when assessing the efficacy of the monthly dapivirine ring, a new longer-acting HIV-1 prevention option for women, we estimated per-sex-act risk reduction associated with product use. METHODS: We conducted a secondary analysis of data from MTN-020/ASPIRE, a phase 3, randomized, placebo-controlled efficacy trial of the dapivirine ring that recruited HIV-uninfected, African women aged 18-45 years. With cumulative sex acts as the time scale, we used multivariable Cox regression with inverse probability of censoring weights to estimate HIV-1 risk reduction associated with a rate of dapivirine release indicative of consistent product use. RESULTS: Women in the dapivirine ring group (n = 1187) had an estimated incidence rate of 2.3 (95% confidence interval [CI], 1.8-3.1) HIV-1 acquisition events per 10 000 sex acts versus 3.6 (95% CI, 2.9-4.4) per 10 000 acts in the placebo group (n = 1187). Dapivirine release indicative of consistent ring use was associated with a 63% (95% CI, 33%-80%) per-sex-act HIV-1 risk reduction. CONCLUSIONS: These results support the efficacy of the dapivirine vaginal ring for HIV-1 prevention and help to inform decision-making for women, providers, and policymakers regarding product use. CLINICAL TRIALS REGISTRATION: NCT01617096.


Assuntos
Fármacos Anti-HIV , Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Soropositividade para HIV , HIV-1 , Pirimidinas , Feminino , Humanos , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Comportamento de Redução do Risco , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade
7.
J Cell Mol Med ; 28(9): e18274, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38676362

RESUMO

TRP channels, are non-specific cationic channels that are involved in multiple physiological processes that include salivation, cellular secretions, memory extinction and consolidation, temperature, pain, store-operated calcium entry, thermosensation and functionality of the nervous system. Here we choose to look at the evidence that decisively shows how TRP channels modulate human neuron plasticity as it relates to the molecular neurobiology of sleep/circadian rhythm. There are numerous model organisms of sleep and circadian rhythm that are the results of the absence or genetic manipulation of the non-specific cationic TRP channels. Drosophila and mice that have had their TRP channels genetically ablated or manipulated show strong evidence of changes in sleep duration, sleep activity, circadian rhythm and response to temperature, noxious odours and pattern of activity during both sleep and wakefulness along with cardiovascular and respiratory function during sleep. Indeed the role of TRP channels in regulating sleep and circadian rhythm is very interesting considering the parallel roles of TRP channels in thermoregulation and thermal response with concomitant responses in growth and degradation of neurites, peripheral nerves and neuronal brain networks. TRP channels provide evidence of an ability to create, regulate and modify our sleep and circadian rhythm in a wide array of physiological and pathophysiological conditions. In the current review, we summarize previous results and novel recent advances in the understanding of calcium ion entry via TRP channels in different sleep and circadian rhythm conditions. We discuss the role of TRP channels in sleep and circadian disorders.


Assuntos
Ritmo Circadiano , Sono , Canais de Potencial de Receptor Transitório , Ritmo Circadiano/fisiologia , Ritmo Circadiano/genética , Animais , Humanos , Sono/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Canais de Potencial de Receptor Transitório/genética
8.
J Physiol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850551

RESUMO

Circadian rhythms, governed by the dominant central clock, in addition to various peripheral clocks, regulate almost all biological processes, including sleep-wake cycles, hormone secretion and metabolism. In certain contexts, the regulation and function of the peripheral oscillations can be decoupled from the central clock. However, the specific mechanisms underlying muscle-intrinsic clock-dependent modulation of muscle function and metabolism remain unclear. We investigated the outcome of perturbations of the primary and secondary feedback loops of the molecular clock in skeletal muscle by specific gene ablation of Period circadian regulator 2 (Per2) and RAR-related orphan receptor alpha (Rorα), respectively. In both models, a dampening of core clock gene oscillation was observed, while the phase was preserved. Moreover, both loops seem to be involved in the homeostasis of amine groups. Highly divergent outcomes were seen for overall muscle gene expression, primarily affecting circadian rhythmicity in the PER2 knockouts and non-oscillating genes in the RORα knockouts, leading to distinct outcomes in terms of metabolome and phenotype. These results highlight the entanglement of the molecular clock and muscle plasticity and allude to specific functions of different clock components, i.e. the primary and secondary feedback loops, in this context. The reciprocal interaction between muscle contractility and circadian clocks might therefore be instrumental to determining a finely tuned adaptation of muscle tissue to perturbations in health and disease. KEY POINTS: Specific perturbations of the primary and secondary feedback loop of the molecular clock result in specific outcomes on muscle metabolism and function. Ablation of Per2 (primary loop) or Rorα (secondary loop) blunts the amplitude of core clock genes, in absence of a shift in phase. Perturbation of the primary feedback loop by deletion of PER2 primarily affects muscle gene oscillation. Knockout of RORα and the ensuing modulation of the secondary loop results in the aberrant expression of a large number of non-clock genes and proteins. The deletion of PER2 and RORα affects muscle metabolism and contractile function in a circadian manner, highlighting the central role of the molecular clock in modulating muscle plasticity.

9.
J Biol Chem ; 299(10): 105219, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660913

RESUMO

Rectal prolapse in serious inflammatory bowel disease is caused by abnormal reactions of the intestinal mucosal immune system. The circadian clock has been implicated in immune defense and inflammatory responses, but the mechanisms by which it regulates gut inflammation remain unclear. In this study, we investigate the role of the rhythmic gene Period2 (Per2) in triggering inflammation in the rectum and its contribution to the pathogenesis of rectal prolapse. We report that Per2 deficiency in mice increased susceptibility to intestinal inflammation and resulted in spontaneous rectal prolapse. We further demonstrated that PER2 was essential for the transcription of glycogen synthase 1 by interacting with the NF-κB p65. We show that the inhibition of Per2 reduced the levels of glycogen synthase 1 and glycogen synthesis in macrophages, impairing the capacity of pathogen clearance and disrupting the composition of gut microbes. Taken together, our findings identify a novel role for Per2 in regulating the capacity of pathogen clearance in macrophages and gut inflammation and suggest a potential animal model that more closely resembles human rectal prolapse.

10.
J Biol Chem ; 299(3): 102929, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682495

RESUMO

Circadian rhythmicity is maintained by a set of core clock proteins including the transcriptional activators CLOCK and BMAL1, and the repressors PER (PER1, PER2, and PER3), CRY (CRY1 and CRY2), and CK1δ. In mice, peak expression of the repressors in the early morning reduces CLOCK- and BMAL1-mediated transcription/translation of the repressors themselves. By late afternoon the repressors are largely depleted by degradation, and thereby their expression is reactivated in a cycle repeated every 24 h. Studies have characterized a variety of possible protein interactions and complexes associated with the function of this transcription-translation feedback loop. Our prior investigation suggested there were two circadian complexes responsible for rhythmicity, one containing CLOCK-BMAL and the other containing PER2, CRY1, and CK1δ. In this investigation, we acquired data from glycerol gradient centrifugation and gel filtration chromatography of mouse liver extracts obtained at different circadian times to further characterize circadian complexes. In addition, anti-PER2 and anti-CRY1 immunoprecipitates obtained from the same extracts were analyzed by liquid chromatography-tandem mass spectrometry to identify components of circadian complexes. Our results confirm the presence of discrete CLOCK-BMAL1 and PER-CRY-CK1δ complexes at the different circadian time points, provide masses of 255 and 707 kDa, respectively, for these complexes, and indicate that these complexes are composed principally of the core circadian proteins.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Animais , Camundongos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Relógios Circadianos/genética , Ritmo Circadiano/genética , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Fígado/metabolismo , Complexos Multiproteicos/metabolismo , Perfilação da Expressão Gênica , Retroalimentação Fisiológica
11.
Ecol Lett ; 27(3): e14396, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38456670

RESUMO

Trait-based ecology has already revealed main independent axes of trait variation defining trait spaces that summarize plant adaptive strategies, but often ignoring intraspecific trait variability (ITV). By using empirical ITV-level data for two independent dimensions of leaf form and function and 167 species across five habitat types (coastal dunes, forests, grasslands, heathlands, wetlands) in the Italian peninsula, we found that ITV: (i) rotated the axes of trait variation that define the trait space; (ii) increased the variance explained by these axes and (iii) affected the functional structure of the target trait space. However, the magnitude of these effects was rather small and depended on the trait and habitat type. Our results reinforce the idea that ITV is context-dependent, calling for careful extrapolations of ITV patterns across traits and spatial scales. Importantly, our study provides a framework that can be used to start integrating ITV into trait space analyses.


Assuntos
Ecossistema , Florestas , Folhas de Planta , Fenótipo , Ecologia
12.
J Cell Biochem ; 125(2): e30513, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38229522

RESUMO

Wound healing can be influenced by genes that control the circadian cycle, including Per2 and BMAL1, which coordinate the functions of several organs, including the skin. The aim of the study was to evaluate the role of PER2 during experimental skin wound healing. Two groups (control and Per2-KO), consisting of 14 male mice each, were anesthetized by inhalation, and two 6 mm wounds were created on their dorsal skin using a punch biopsy. A silicone ring was sutured around the wound perimeter to restrict contraction. The wound healing process was clinically measured daily (closure index) until complete wound repair. On Day 6, histomorphometric analysis was performed using the length and thickness of the epithelial migration tongue, in addition to counting vessels underlying the lesion by immunofluorescence assay and maturation of collagen fibers through picrosirius staining. Bromodeoxyuridine (BrdU) incorporation and quantification were performed using the subcutaneous injection technique 2 h before euthanasia and through immunohistochemical analysis of the proliferative index. In addition, the qualitative analysis of myofibroblasts and periostin distribution in connective tissue was performed by immunofluorescence. Statistically significant differences were observed in the healing time between the experimental groups (means: 15.5 days for control mice and 13.5 days for Per2-KO; p = 0.001). The accelerated healing observed in the Per2-KO group (p < 0.05) was accompanied by statistical differences in wound diameter and length of the migrating epithelial tongue (p = 0.01) compared to the control group. Regarding BrdU immunoreactivity, higher expression was observed in the intact epithelium of Per2-KO animals (p = 0.01), and this difference compared to control was also present, to a lesser extent, at the wound site (p = 0.03). Immunofluorescence in the connective tissue underlying the wound showed a higher angiogenic potential in the Per2-KO group in the intact tissue area and the wound region (p < 0.01), where increased expression of myofibroblasts was also observed. Qualitative analysis revealed the distribution of periostin protein and collagen fibers in the connective tissue underlying the wound, with greater organization and maturation during the analyzed period. Our research showed that the absence of the Per2 gene positively impacts the healing time of the skin in vivo. This acceleration depends on the increase of epithelial proliferative and angiogenic capacity of cells carrying the Per2 deletion.


Assuntos
Pele , Cicatrização , Camundongos , Masculino , Animais , Cicatrização/genética , Bromodesoxiuridina , Pele/lesões , Epiderme , Colágeno , Proteínas Circadianas Period/genética
13.
J Cell Biochem ; 125(7): e30581, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38747499

RESUMO

Cardiovascular disorders are still challenging and are among the deadly diseases. As a major risk factor for atherosclerotic cardiovascular disease, dyslipidemia, and high low-density lipoprotein cholesterol in particular, can be prevented primary and secondary by lipid-lowering medications. Therefore, insights are still needed into designing new drugs with minimal side effects. Proprotein convertase subtilisin/kexin 9 (PCSK9) enzyme catalyses protein-protein interactions with low-density lipoprotein, making it a critical target for designing promising inhibitors compared to statins. Therefore, we screened for potential compounds using a redesigned PCSK9 conformational behaviour to search for a significantly extensive chemical library and investigated the inhibitory mechanisms of the final compounds using integrated computational methods, from ligand essential functional group screening to all-atoms MD simulations and MMGBSA-based binding free energy. The inhibitory mechanisms of the screened compounds compared with the standard inhibitor. K31 and K34 molecules showed stronger interactions for PCSK9, having binding energy (kcal/mol) of -33.39 and -63.51, respectively, against -27.97 of control. The final molecules showed suitable drug-likeness, non-mutagenesis, permeability, and high solubility values. The C-α atoms root mean square deviation and root mean square fluctuation of the bound-PCSK9 complexes showed stable and lower fluctuations compared to apo PCSK9. The findings present a model that unravels the mechanism by which the final molecules proposedly inhibit the PCSK9 function and could further improve the design of novel drugs against cardiovascular diseases.


Assuntos
Aterosclerose , Simulação de Dinâmica Molecular , Inibidores de PCSK9 , Pró-Proteína Convertase 9 , Humanos , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/química , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Desenho de Fármacos , Doenças Cardiovasculares/tratamento farmacológico , Farmacóforo
14.
Int J Cancer ; 154(6): 979-991, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37902275

RESUMO

Human exposure to per- and polyfluoroalkyl substances (PFAS) occurs globally through contaminated food, dust, and drinking water. Studies of PFAS and thyroid cancer have been limited. We conducted a nested case-control study of prediagnostic serum levels of 19 PFAS and papillary thyroid cancer (400 cases, 400 controls) in the Finnish Maternity Cohort (pregnancies 1986-2010; follow-up through 2016), individually matched on sample year and age. We used conditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) for log2 transformed and categorical exposures, overall and stratified by calendar period, birth cohort, and median age at diagnosis. We adjusted for other PFAS with Spearman correlation rho = 0.3-0.6. Seven PFAS, including perfluoroctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), N-ethyl-perfluorooctane sulfonamidoacetic acid (EtFOSAA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluorohexane sulfonic acid (PFHxS) were detected in >50% of women. These PFAS were not associated with risk of thyroid cancer, except for PFHxS, which was inversely associated (OR log2 = 0.82, 95% CI: 0.70-0.97). We observed suggestive but imprecise increased risks associated with PFOA, PFOS, and EtFOSAA for those diagnosed at ages <40 years, whereas associations were null or inverse among those diagnosed at 40+ years (P-interaction: .02, .08, .13, respectively). There was little evidence of other interactions. These results show no clear association between PFAS and papillary thyroid cancer risk. Future work would benefit from evaluation of these relationships among those with higher exposure levels and during periods of early development when the thyroid gland may be more susceptible to environmental harms.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Ácidos Sulfônicos , Neoplasias da Glândula Tireoide , Humanos , Feminino , Gravidez , Câncer Papilífero da Tireoide/epidemiologia , Estudos de Casos e Controles , Finlândia/epidemiologia , Fluorocarbonos/efeitos adversos , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia
15.
Am J Epidemiol ; 193(3): 454-468, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37846096

RESUMO

Results of toxicological studies indicate that phthalates and per-/polyfluoroalkyl substances (PFAS), 2 classes of endocrine-disrupting chemicals, may alter the functioning of the hypothalamic-pituitary-adrenocortical (HPA) axis. We evaluated the associations of urinary phthalate metabolites and serum PFAS during gestation and childhood with adolescent hair cortisol concentrations (pg/mg hair) at age 12 years, an integrative marker of HPA axis activity (n = 205 mother-child pairs; Cincinnati, Ohio; enrolled 2003-2006). We used quantile-based g-computation to estimate associations between mixtures of urinary phthalate metabolites or serum PFAS and hair cortisol. We also examined whether associations of individual phthalate metabolites or PFAS with cortisol varied by the timing of exposure. We found that a 1-quartile increase in all childhood phthalate metabolites was associated with 35% higher adolescent hair cortisol (phthalate mixture ψ = 0.13; 95% confidence interval: 0.03, 0.22); these associations were driven by monoethyl phthalate, monoisobutyl phthalate, and monobenzyl phthalate. We did not find evidence that phthalate metabolites during gestation or serum PFAS mixtures were related to adolescent hair cortisol concentrations. We found suggestive evidence that higher childhood concentrations of individual PFAS were related to higher and lower adolescent hair cortisol concentrations. Our results suggest that phthalate exposure during childhood may contribute to higher levels of chronic HPA axis activity.


Assuntos
Poluentes Ambientais , Fluorocarbonos , Ácidos Ftálicos , Humanos , Adolescente , Criança , Poluentes Ambientais/urina , Hidrocortisona , Sistema Hipotálamo-Hipofisário/química , Sistema Hipófise-Suprarrenal/química , Fluorocarbonos/toxicidade , Exposição Ambiental/efeitos adversos
16.
Am J Epidemiol ; 193(8): 1182-1196, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38400646

RESUMO

We synthesized the epidemiologic evidence on the associations between per- and polyfluoroalkyl substances (PFAS) exposure and breast cancer risk. Our systematic review and meta-analysis included 18 and 11 articles, respectively, covering studies up to February 2023. The summary relative risks (RRs) estimated by random-effects meta-analyses did not support an association between PFAS and overall breast cancer risk (eg, a natural log (ln)-unit increase in serum/plasma concentrations [ng/mL] for perfluorooctanoate [PFOA] RR = 0.95; 95% CI, 0.77-1.18; perfluorooctane sulfonate [PFOS] RR = 0.98; 95% CI, 0.87-1.11). However, when limiting to studies that assessed exposures prior to a breast cancer diagnosis, we observed a positive association with PFOA (a ln-unit increase, RR = 1.16; 95% CI, 0.96-1.40). We also observed some possible heterogeneous associations by tumor estrogen and progesterone receptor status among postmenopausal breast cancer cases. No meaningful changes were observed after excluding the studies with high risk of bias (Tier 3). Based on the evaluation tool developed by the National Toxicology Program, given the heterogeneity across studies and the variability in timing of exposure measurements, the epidemiologic evidence needed to determine the association between PFAS exposure and breast cancer remains inadequate. Our findings support the need for future studies with improved study designs to determine this association.


Assuntos
Neoplasias da Mama , Caprilatos , Exposição Ambiental , Fluorocarbonos , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/sangue , Fluorocarbonos/sangue , Fluorocarbonos/efeitos adversos , Feminino , Caprilatos/sangue , Exposição Ambiental/efeitos adversos , Ácidos Alcanossulfônicos/sangue , Estudos Epidemiológicos
17.
Am Nat ; 203(4): 458-472, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489780

RESUMO

AbstractEcologists increasingly recognize that interactions between two species can be affected by the density of a third species. How these higher-order interactions (HOIs) affect species persistence remains poorly understood. To explore the effect of HOIs stemming from multiple trophic layers on a plant community composition, we experimentally built a mesocosm with three plants and three pollinator species arranged in a fully nested and modified network structure. We estimated pairwise interactions among plants and between plants and pollinators, as well as HOIs initiated by a plant or a pollinator affecting plant species pairs. Using a structuralist approach, we evaluated the consequences of the statistically supported HOIs on the persistence probability of each of the three competing plant species and their combinations. HOIs substantially redistribute the strength and sign of pairwise interactions between plant species, promoting the opportunities for multispecies communities to persist compared with a non-HOI scenario. However, the physical elimination of a plant-pollinator link in the modified network structure promotes changes in per capita pairwise interactions and HOIs, resulting in a single-species community. Our study provides empirical evidence of the joint importance of HOIs and network structure in determining species persistence within diverse communities.


Assuntos
Plantas , Polinização
18.
Artigo em Inglês | MEDLINE | ID: mdl-39214390

RESUMO

BACKGROUND & AIMS: There is significant variability in the immediate post-operative and long-term management of patients undergoing per-oral endoscopic myotomy (POEM), largely stemming from the lack of high-quality evidence. We aimed to establish a consensus on several important questions on the after care of post-POEM patients through a modified Delphi process. METHODS: A steering committee developed an initial questionnaire consisting of 5 domains (33 statements): post-POEM admission/discharge, indication for immediate post-POEM esophagram, peri-procedural medications and diet resumption, clinic follow-up recommendations, and post-POEM reflux surveillance and management. A total of 34 experts participated in the 2 rounds of the Delphi process, with quantitative and qualitative data analyzed for each round to achieve consensus. RESULTS: A total of 23 statements achieved a high degree of consensus. Overall, the expert panel agreed on the following: (1) same-day discharge after POEM can be considered in select patients; (2) a single dose of prophylactic antibiotics may be as effective as a short course; (3) a modified diet can be advanced as tolerated; and (4) all patients should be followed in clinic and undergo objective testing for surveillance and management of reflux. Consensus could not be achieved on the indication of post-POEM esophagram to evaluate for leak. CONCLUSIONS: The results of this Delphi process established expert agreement on several important issues and provides practical guidance on key aspects in the care of patients following POEM.

19.
Gastroenterology ; 164(7): 1108-1118.e3, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36907524

RESUMO

BACKGROUND & AIMS: For patients with achalasia experiencing persistent or recurrent symptoms after laparoscopic Heller myotomy (LHM), pneumatic dilation (PD) is the most frequently used treatment. Per-oral endoscopic myotomy (POEM) is increasingly being investigated as rescue therapy. This study aimed to determine the efficacy of POEM vs PD for patients with persistent or recurrent symptoms after LHM. METHODS: This randomized multicenter controlled trial included patients after LHM with an Eckardt score >3 and substantial stasis (≥2 cm) on timed barium esophagogram and randomized to POEM or PD. The primary outcome was treatment success, defined as an Eckardt score of ≤3 and without unscheduled re-treatment. Secondary outcomes included the presence of reflux esophagitis, high-resolution manometry, and timed barium esophagogram findings. Follow-up duration was 1 year after initial treatment. RESULTS: Ninety patients were included. POEM had a higher success rate (28 of 45 patients [62.2%]) than PD (12 of 45 patients [26.7%]; absolute difference, 35.6%; 95% CI, 16.4%-54.7%; P = .001; odds ratio, 0.22; 95% CI, 0.09-0.54; relative risk for success, 2.33; 95% CI, 1.37-3.99). Reflux esophagitis was not significantly different between POEM (12 of 35 [34.3%]) and PD (6 of 40 [15%]). Basal lower esophageal sphincter pressure and integrated relaxation pressure (IRP-4) were significantly lower in the POEM group (P = .034; P = .002). Barium column height after 2 and 5 minutes was significantly less in patients treated with POEM (P = .005; P = .015). CONCLUSIONS: Among patients with achalasia experiencing persistent or recurrent symptoms after LHM, POEM resulted in a significantly higher success rate than PD, with a numerically higher incidence of grade A-B reflux esophagitis. NETHERLANDS TRIAL REGISTRY: NL4361 (NTR4501), https://trialsearch.who.int/Trial2.aspx?TrialID = NTR4501.


Assuntos
Acalasia Esofágica , Esofagite Péptica , Miotomia de Heller , Cirurgia Endoscópica por Orifício Natural , Humanos , Acalasia Esofágica/diagnóstico , Acalasia Esofágica/cirurgia , Miotomia de Heller/efeitos adversos , Miotomia de Heller/métodos , Esfíncter Esofágico Inferior/cirurgia , Dilatação/efeitos adversos , Dilatação/métodos , Bário , Resultado do Tratamento , Esofagite Péptica/diagnóstico , Esofagite Péptica/etiologia , Esofagite Péptica/terapia , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Cirurgia Endoscópica por Orifício Natural/métodos
20.
BMC Plant Biol ; 24(1): 271, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605289

RESUMO

BACKGROUND: Agropyron cristatum (L.) is a valuable genetic resource for expanding the genetic diversity of common wheat. Pubing3228, a novel wheat-A. cristatum hybrid germplasm, exhibits several desirable agricultural traits, including high grain number per spike (GNS). Understanding the genetic architecture of GNS in Pubing3228 is crucial for enhancing wheat yield. This study aims to analyze the specific genetic regions and alleles associated with high GNS in Pubing3228. METHODS: The study employed a recombination inbred line (RIL) population derived from a cross between Pubing3228 and Jing4839 to investigate the genetic regions and alleles linked to high GNS. Quantitative Trait Loci (QTL) analysis and candidate gene investigation were utilized to explore these traits. RESULTS: A total of 40 QTLs associated with GNS were identified across 16 chromosomes, accounting for 4.25-17.17% of the total phenotypic variation. Five QTLs (QGns.wa-1D, QGns.wa-5 A, QGns.wa-7Da.1, QGns.wa-7Da.2 and QGns.wa-7Da.3) accounter for over 10% of the phenotypic variation in at least two environments. Furthermore, 94.67% of the GNS QTL with positive effects originated from Pubing3228. Candidate gene analysis of stable QTLs identified 11 candidate genes for GNS, including a senescence-associated protein gene (TraesCS7D01G148000) linked to the most significant SNP (AX-108,748,734) on chromosome 7D, potentially involved in reallocating nutrients from senescing tissues to developing seeds. CONCLUSION: This study provides new insights into the genetic mechanisms underlying high GNS in Pubing3228, offering valuable resources for marker-assisted selection in wheat breeding to enhance yield.


Assuntos
Agropyron , Locos de Características Quantitativas , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Agropyron/genética , Melhoramento Vegetal , Ligação Genética , Triticum/genética , Fenótipo , Grão Comestível/genética
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