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1.
ACS Biomater Sci Eng ; 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39305230

RESUMEN

Extracellular vesicles (EVs) are physiological vectors for the intercellular transport of a variety of molecules. Among these, small RNAs, and especially microRNAs (miRNAs), have been identified as prevalent components, and there has thus been a robust investigation of EVs for therapeutic miRNAs delivery. However, intrinsic levels of EV-associated miRNAs are generally too low to enable efficient and effective therapeutic outcomes. We hypothesized that miRNA localization to EVs could be improved by limiting competing interactions that occur throughout the miRNA biogenesis process. Using miR-146a-5p as a model, modulation of transcription, nuclear export, and enzymatic cleavage steps of miRNA biogenesis were tested for impact on EV miRNA loading. Working in HEK293T cells, various alterations in the EV biogenesis pathway were shown to impact miRNA localization to EVs. The system was then applied in induced pluripotent stem cells (iPSCs), a more promising substrate for therapeutic EV production, and EVs were separated and assessed for anti-inflammatory efficacy in vitro and in a murine colitis model, where the preservation of function was validated. Overall, the results highlight necessary considerations when designing a cell culture system for the devoted production of miRNA-loaded EVs.

2.
J Viral Hepat ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39148449

RESUMEN

Chronic hepatitis B (CHB) is the leading cause of hepatocellular carcinoma (HCC) globally. We described and evaluated the outcomes of patients with CHB-HCC in Canada. In this retrospective cross-sectional cohort study, data were analysed from CHB mono-infected subjects seen between 1 January 2012 and 31 December 2022, and entered the Canadian Hepatitis B Network Registry. Descriptive analysis and chi-squared modelling were used to compare cohorts, followed by multivariable survival analysis regarding survival post-diagnosis. Statistical analyses were completed in R version 2.2. Of the 6711 patients with CHB who met inclusion criteria, 232 (3.5%) developed HCC. Compared with the CHB cohort, the majority of CHB-HCC cohort were male, SEA and HBeAg negative and born in endemic area (80% vs. 56%, 73% vs. 55%, 84% vs. 54%, 64% vs. 40% and all p < 0001). Overall, median HBV DNA level was log 2.54 (IQR: 0-4.04). Advanced liver disease, defined as minimum Fibrosis stage F3, was seen in 9.4% of overall cohort, but 92% of HCC cohort. At diagnosis, median tumour size was 2.5 cm (IQR: 1.7-4.0) and mean tumour number was 1.33 (SD: 1.33), with 81% of patients BCLC 0-A. Fifty-three per cent of patients were diagnosed with HCC as part of surveillance protocols. The survival rate after HCC diagnosis was 78.7%, during the median follow-up of 52.9 months (IQR: 17-90). In multivariable analysis, survival was significantly correlated with diagnosis through the screening programme. In this large cohort of patients with CHB-HCC, the majority of patients were detected with early-stage HCC and received treatment with curative intent, resulting in strong survival rates.

3.
Nat Commun ; 15(1): 6524, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107278

RESUMEN

Sequence-based genetic testing identifies causative variants in ~ 50% of individuals with developmental and epileptic encephalopathies (DEEs). Aberrant changes in DNA methylation are implicated in various neurodevelopmental disorders but remain unstudied in DEEs. We interrogate the diagnostic utility of genome-wide DNA methylation array analysis on peripheral blood samples from 582 individuals with genetically unsolved DEEs. We identify rare differentially methylated regions (DMRs) and explanatory episignatures to uncover causative and candidate genetic etiologies in 12 individuals. Using long-read sequencing, we identify DNA variants underlying rare DMRs, including one balanced translocation, three CG-rich repeat expansions, and four copy number variants. We also identify pathogenic variants associated with episignatures. Finally, we refine the CHD2 episignature using an 850 K methylation array and bisulfite sequencing to investigate potential insights into CHD2 pathophysiology. Our study demonstrates the diagnostic yield of genome-wide DNA methylation analysis to identify causal and candidate variants as 2% (12/582) for unsolved DEE cases.


Asunto(s)
Variaciones en el Número de Copia de ADN , Metilación de ADN , Epilepsia , Humanos , Metilación de ADN/genética , Femenino , Niño , Masculino , Epilepsia/genética , Epilepsia/diagnóstico , Variaciones en el Número de Copia de ADN/genética , Preescolar , Proteínas de Unión al ADN/genética , Adolescente , Pruebas Genéticas/métodos , Lactante
4.
Res Sq ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38883791

RESUMEN

Background: Permanent supportive housing (PSH) is an evidence-based practice for reducing homelessness that subsidizes permanent, independent housing and provides case management-including linkages to health services. Substance use disorders (SUDs) are common contributing factors towards premature, unwanted ("negative") PSH exits; little is known about racial/ethnic differences in negative PSH exits among residents with SUDs. Within the nation's largest PSH program at the Department of Veterans Affairs (VA), we examined relationships among SUDs and negative PSH exits (for up to five years post-PSH move-in) across racial/ethnic subgroups. Methods: We used VA administrative data to identify a cohort of homeless-experienced Veterans (HEVs) (n = 2,712) who were housed through VA Greater Los Angeles' PSH program from 2016-2019. We analyzed negative PSH exits by HEVs with and without SUDs across racial/ethnic subgroups (i.e., African American/Black, Non-Hispanic White, Hispanic/Latino, and Other/Mixed [Asian, American Indian or Alaskan Native, and Native Hawaiian or Other Pacific Islander, and multi-race]) in controlled models and accounting for competing risk of death. Results: In competing risk models, HEVs with at least one SUD had 1.3 times the hazard of negative PSH exits compared to those without SUDs (95% CI: 1.00, 1.61). When stratifying by race/ethnicity, Other/Mixed race residents with at least one SUD had 6.4 times the hazard of negative PSH exits compared to their peers without SUDs (95% CI: 1.61-25.50). Hispanic/Latino residents with at least one SUD had 1.9 times the hazard compared to those without SUDs, also indicating a strong relationship with negative PSH exits; however, this association was not statistically significant (95% CI: 0.85-4.37). Black residents with at least one SUD had 1.2 times the hazard compared to those without SUDs (95% CI: 0.85-1.64), indicating no evidence of an association with negative PSH exits. Similarly, Non-Hispanic White residents with at least one SUD had 1.1 times the hazard compared to those without SUDs (95% CI: 0.75-1.66). Conclusions: These findings suggest relationships between SUDs and negative PSH exits differ between race/ethnic groups and suggest there may be value in culturally specific tailoring and implementation of SUD services for these subgroups.

5.
Ecol Lett ; 27(6): e14460, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38877759

RESUMEN

Mast seeding is a well-documented phenomenon across diverse forest ecosystems. While its effect on aboveground food webs has been thoroughly studied, how it impacts the soil fungi that drive soil carbon and nutrient cycling has not yet been explored. To evaluate the relationship between mast seeding and fungal resource availability, we paired a Swiss 29-year fungal sporocarp census with contemporaneous seed production for European beech (Fagus sylvatica L.). On average, mast seeding was associated with a 55% reduction in sporocarp production and a compositional community shift towards drought-tolerant taxa across both ectomycorrhizal and saprotrophic guilds. Among ectomycorrhizal fungi, traits associated with carbon cost did not explain species' sensitivity to seed production. Together, our results support a novel hypothesis that mast seeding limits annual resource availability and reproductive investment in soil fungi, creating an ecosystem 'rhythm' to forest processes that is synchronized above- and belowground.


Asunto(s)
Fagus , Micorrizas , Fagus/microbiología , Micorrizas/fisiología , Biodiversidad , Microbiología del Suelo , Semillas/microbiología , Suiza , Hongos/fisiología , Micobioma
6.
Curr Opin Biotechnol ; 85: 103067, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38277970

RESUMEN

Extracellular vesicles (EVs) are an emergent next-generation biotechnology with broad application potential. In particular, immunomodulatory bioactivity of EVs leading to anti-inflammatory effects is well-characterized. Cell source and culture conditions are critical determinants of EV therapeutic efficacy, while augmenting EV anti-inflammatory bioactivity via diverse strategies, including RNA cargo loading and protein surface display, has proven effective. Yet, translational challenges remain. Additionally, the potential of direct antimicrobial EV functionality has only recently emerged but offers the possibility of overcoming drug-resistant bacterial and fungal infections through novel, multifactorial mechanisms. As discussed herein, these application areas are brought together by the potential for synergistic benefit from technological developments related to EV cargo loading and biomanufacturing.


Asunto(s)
Vesículas Extracelulares , Humanos , Comunicación Celular , ARN/metabolismo , Inflamación/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Antiinflamatorios/metabolismo , Antiinflamatorios/farmacología
7.
New Phytol ; 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38073143

RESUMEN

Rising atmospheric carbon dioxide concentrations (CO2 ) and atmospheric nitrogen (N) deposition have contrasting effects on ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) symbioses, potentially mediating forest responses to environmental change. In this study, we evaluated the cumulative effects of historical environmental change on N concentrations and δ15 N values in AM plants, EM plants, EM fungi, and saprotrophic fungi using herbarium specimens collected in Minnesota, USA from 1871 to 2016. To better understand mycorrhizal mediation of foliar δ15 N, we also analyzed a subset of previously published foliar δ15 N values from across the United States to parse the effects of N deposition and CO2 rise. Over the last century in Minnesota, N concentrations declined among all groups except saprotrophic fungi. δ15 N also declined among all groups of plants and fungi; however, foliar δ15 N declined less in EM plants than in AM plants. In the analysis of previously published foliar δ15 N values, this slope difference between EM and AM plants was better explained by nitrogen deposition than by CO2 rise. Mycorrhizal type did not explain trajectories of plant N concentrations. Instead, plants and EM fungi exhibited similar declines in N concentrations, consistent with declining forest N status despite moderate levels of N deposition.

8.
medRxiv ; 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37873138

RESUMEN

Sequence-based genetic testing currently identifies causative genetic variants in ∼50% of individuals with developmental and epileptic encephalopathies (DEEs). Aberrant changes in DNA methylation are implicated in various neurodevelopmental disorders but remain unstudied in DEEs. Rare epigenetic variations ("epivariants") can drive disease by modulating gene expression at single loci, whereas genome-wide DNA methylation changes can result in distinct "episignature" biomarkers for monogenic disorders in a growing number of rare diseases. Here, we interrogate the diagnostic utility of genome-wide DNA methylation array analysis on peripheral blood samples from 516 individuals with genetically unsolved DEEs who had previously undergone extensive genetic testing. We identified rare differentially methylated regions (DMRs) and explanatory episignatures to discover causative and candidate genetic etiologies in 10 individuals. We then used long-read sequencing to identify DNA variants underlying rare DMRs, including one balanced translocation, three CG-rich repeat expansions, and two copy number variants. We also identify pathogenic sequence variants associated with episignatures; some had been missed by previous exome sequencing. Although most DEE genes lack known episignatures, the increase in diagnostic yield for DNA methylation analysis in DEEs is comparable to the added yield of genome sequencing. Finally, we refine an episignature for CHD2 using an 850K methylation array which was further refined at higher CpG resolution using bisulfite sequencing to investigate potential insights into CHD2 pathophysiology. Our study demonstrates the diagnostic yield of genome-wide DNA methylation analysis to identify causal and candidate genetic causes as ∼2% (10/516) for unsolved DEE cases.

9.
mSystems ; 8(4): e0039023, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37338274

RESUMEN

Microbial necromass contributes significantly to both soil carbon (C) persistence and ecosystem nitrogen (N) availability, but quantitative estimates of C and N movement from necromass into soils and decomposer communities are lacking. Additionally, while melanin is known to slow fungal necromass decomposition, how it influences microbial C and N acquisition as well as elemental release into soils remains unclear. Here, we tracked decomposition of isotopically labeled low and high melanin fungal necromass and measured 13C and 15N accumulation in surrounding soils and microbial communities over 77 d in a temperate forest in Minnesota, USA. Mass loss was significantly higher from low melanin necromass, corresponding with greater 13C and 15N soil inputs. A taxonomically and functionally diverse array of bacteria and fungi was enriched in 13C and/or 15N at all sampling points, with enrichment being consistently higher on low melanin necromass and earlier in decomposition. Similar patterns of preferential C and N enrichment of many bacterial and fungal genera early in decomposition suggest that both microbial groups co-contribute to the rapid assimilation of resource-rich soil organic matter inputs. While overall richness of taxa enriched in C was higher than in N for both bacteria and fungi, there was a significant positive relationship between C and N in co-enriched taxa. Collectively, our results demonstrate that melanization acts as a key ecological trait mediating not only fungal necromass decomposition rate but also necromass C and N release and that both elements are rapidly co-utilized by diverse bacterial and fungal decomposers in natural settings. IMPORTANCE Recent studies indicate that microbial dead cells, particularly those of fungi, play an important role in long-term carbon persistence in soils. Despite this growing recognition, how the resources within dead fungal cells (also known as fungal necromass) move into decomposer communities and soils are poorly quantified, particularly in studies based in natural environments. In this study, we found that the contribution of fungal necromass to soil carbon and nitrogen availability was slowed by the amount of melanin present in fungal cell walls. Further, despite the overall rapid acquisition of carbon and nitrogen from necromass by a diverse range of both bacteria and fungi, melanization also slowed microbial uptake of both elements. Collectively, our results indicate that melanization acts as a key ecological trait mediating not only fungal necromass decomposition rate, but also necromass carbon and nitrogen release into soil as well as microbial resource acquisition.


Asunto(s)
Microbiota , Suelo , Carbono , Nitrógeno/análisis , Melaninas , Hongos , Bacterias
10.
Adv Healthc Mater ; 12(26): e2300879, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37335811

RESUMEN

Extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) have recently been explored in clinical trials for treatment of diseases with complex pathophysiologies. However, production of MSC EVs is currently hampered by donor-specific characteristics and limited ex vivo expansion capabilities before decreased potency, thus restricting their potential as a scalable and reproducible therapeutic. Induced pluripotent stem cells (iPSCs) represent a self-renewing source for obtaining differentiated iPSC-derived MSCs (iMSCs), circumventing both scalability and donor variability concerns for therapeutic EV production. Thus, it is initially sought to evaluate the therapeutic potential of iMSC EVs. Interestingly, while utilizing undifferentiated iPSC EVs as a control, it is found that their vascularization bioactivity is similar and their anti-inflammatory bioactivity is superior to donor-matched iMSC EVs in cell-based assays. To supplement this initial in vitro bioactivity screen, a diabetic wound healing mouse model where both the pro-vascularization and anti-inflammatory activity of these EVs would be beneficial is employed. In this in vivo model, iPSC EVs more effectively mediate inflammation resolution within the wound bed. Combined with the lack of additional differentiation steps required for iMSC generation, these results support the use of undifferentiated iPSCs as a source for therapeutic EV production with respect to both scalability and efficacy.


Asunto(s)
Diabetes Mellitus , Vesículas Extracelulares , Células Madre Pluripotentes Inducidas , Ratones , Animales , Diferenciación Celular/fisiología , Antiinflamatorios , Cicatrización de Heridas
11.
Pharmacoepidemiol Drug Saf ; 32(10): 1178-1183, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37345505

RESUMEN

PURPOSE: Immediate-release forms of generic mixed amphetamine salts (MAS) have been the subject of passive surveillance reports signaling lack of effectiveness. We examined switching patterns that might suggest whether long-term users of specific MAS are more likely to switch away or switch back after use of the MAS of interest in the FDA's Sentinel Distributed Database. METHODS: We required at least 60-day continuous supply of selected MAS grouped by Abbreviated New Drug Application (ANDA) to describe patterns of switching away from and to generics approved under the ANDAs of interest among individuals ages 15-64 years with attention deficit hyperactivity disorder or narcolepsy during 2013-2019. RESULTS: We observed the greatest number of treatment episodes for ANDA 040422 (n = 525 771), followed by ANDA 202424 (n = 181 693), ANDA 040439 (n = 62 363), ANDA 040440 (n = 21 143), and ANDA 040480 (n = 8792). Of those with switches away from their original ANDA, episodes initiated on generic products under ANDA 040422 (48.6%) and ANDA 202424 (43.0%) were most likely to switch back, while those initiated on generic product under ANDA 040480 were least likely (24.1%). Of those episodes with switches to a generic under an ANDA of interest, about one-third (range 27.1% to 37.0%) switched back to the same product. These switches back had a median time to switch of about 30 days. CONCLUSIONS: These descriptive analyses, although subject to limitations, did not suggest increased switching away or switching back after use of the generics of interest. Continued post-marketing surveillance is warranted.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Narcolepsia , Humanos , Estados Unidos/epidemiología , Anfetamina/uso terapéutico , Sales (Química)/uso terapéutico , Medicaid , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Medicamentos Genéricos/uso terapéutico
12.
Arthritis Rheumatol ; 75(5): 794-805, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36457235

RESUMEN

OBJECTIVE: In gout, hyperuricemia promotes urate crystal deposition, which stimulates the NLRP3 inflammasome and interleukin-1ß (IL-1ß)-mediated arthritis. Incident gout without background hyperuricemia is rarely reported. To identify hyperuricemia-independent mechanisms driving gout incidence and progression, we characterized erosive urate crystalline inflammatory arthritis in a young female patient with normouricemia diagnosed as having sufficient and weighted classification criteria for gout according to the American College of Rheumatology (ACR)/EULAR gout classification criteria (the proband). METHODS: We conducted whole-genome sequencing, quantitative proteomics, whole-blood RNA-sequencing analysis using serum samples from the proband. We used a mouse model of IL-1ß-induced knee synovitis to characterize proband candidate genes, biomarkers, and pathogenic mechanisms of gout. RESULTS: Lubricin level was attenuated in human proband serum and associated with elevated acute-phase reactants and inflammatory whole-blood transcripts and transcriptional pathways. The proband had predicted damaging gene variants of NLRP3 and of inter-α trypsin inhibitor heavy chain 3, an inhibitor of lubricin-degrading cathepsin G. Changes in the proband's serum protein interactome network supported enhanced lubricin degradation, with cathepsin G activity increased relative to its inhibitors, SERPINB6 and thrombospondin 1. Activation of Toll-like receptor 2 (TLR-2) suppressed levels of lubricin mRNA and lubricin release in cultured human synovial fibroblasts (P < 0.01). Lubricin blunted urate crystal precipitation and IL-1ß induction of xanthine oxidase and urate in cultured macrophages (P < 0.001). In lubricin-deficient mice, injection of IL-1ß in knees increased xanthine oxidase-positive synovial resident M1 macrophages (P < 0.05). CONCLUSION: Our findings linked normouricemic erosive gout to attenuated lubricin, with impaired control of cathepsin G activity, compounded by deleterious NLRP3 variants. Lubricin suppressed monosodium urate crystallization and blunted IL-1ß-induced increases in xanthine oxidase and urate in macrophages. The collective activities of articular lubricin that could limit incident and erosive gouty arthritis independently of hyperuricemia are subject to disruption by inflammation, activated cathepsin G, and synovial fibroblast TLR-2 signaling.


Asunto(s)
Artritis Gotosa , Gota , Hiperuricemia , Femenino , Humanos , Ratones , Animales , Receptor Toll-Like 2/genética , Catepsina G/efectos adversos , Ácido Úrico , Proteína con Dominio Pirina 3 de la Familia NLR , Xantina Oxidasa , Gota/genética , Inflamación/metabolismo , Interleucina-1beta/metabolismo
13.
J Hypertens ; 40(10): 1950-1959, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35969204

RESUMEN

OBJECTIVES: We aimed to estimate the effects of indoor and outdoor temperature on wintertime blood pressure (BP) among peri-urban Beijing adults. METHODS: We enrolled 1279 adults (ages: 40-89 years) and conducted measurements in two winter campaigns in 2018-2019 and 2019-2020. Study staff traveled to participant homes to administer a questionnaire and measure brachial and central BP. Indoor temperature was measured in the 5 min prior to BP measurement. Outdoor temperature was estimated from regional meteorological stations. We used multivariable mixed-effects regression models to estimate the within-individual and between-individual effects of indoor and outdoor temperatures on BP. RESULTS: Indoor and outdoor temperatures ranged from 0.0 to 28 °C and -14.3 to 6.4 °C, respectively. In adjusted models, a 1 °C increase in indoor temperature was associated with decreased SBP [-0.4 mmHg, 95% confidence interval (CI): -0.7 to -0.1 (between-individual; brachial and central BP); -0.5 mmHg, 95% CI: -0.8 to -0.2 (within-individual, brachial BP); -0.4 mmHg, 95% CI: -0.7 to -0.2 (within-individual, central BP)], DBP [-0.2 mmHg, 95% CI:-0.4 to -0.03 (between-individual); -0.3 mmHg, 95% CI: -0.5 to -0.04 (within-individual)], and within-individual pulse pressure [-0.2 mmHg, 95% CI: -0.4 to -0.04 (central); -0.3 mmHg, 95% CI: -0.4 to -0.1 (brachial)]. Between-individual SBP estimates were larger among participants with hypertension. There was no evidence of an effect of outdoor temperature on BP. CONCLUSION: Our results support previous findings of inverse associations between indoor temperature and BP but contrast with prior evidence of an inverse relationship with outdoor temperature. Wintertime home heating may be a population-wide intervention strategy for high BP and cardiovascular disease in China.


Asunto(s)
Hipertensión , Adulto , Anciano , Anciano de 80 o más Años , Presión Sanguínea/fisiología , China , Humanos , Hipertensión/epidemiología , Hipertensión/etiología , Estudios Longitudinales , Persona de Mediana Edad , Temperatura
14.
J Am Chem Soc ; 143(38): 15873-15881, 2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-34542286

RESUMEN

A Ni/photoredox-catalyzed enantioselective reductive coupling of styrene oxides and aryl iodides is reported. This reaction affords access to enantioenriched 2,2-diarylalcohols from racemic epoxides via a stereoconvergent mechanism. Multivariate linear regression (MVLR) analysis with 29 bioxazoline (BiOx) and biimidazoline (BiIm) ligands revealed that enantioselectivity correlates with electronic properties of the ligands, with more electron-donating ligands affording higher ee's. Experimental and computational mechanistic studies were conducted, lending support to the hypothesis that reductive elimination is enantiodetermining and the electronic character of the ligands influences the enantioselectivity by altering the position of the transition state structure along the reaction coordinate. This study demonstrates the benefits of utilizing statistical modeling as a platform for mechanistic understanding and provides new insight into an emerging class of chiral ligands for stereoconvergent Ni and Ni/photoredox cross-coupling.


Asunto(s)
Compuestos Epoxi/química , Yoduros/química , Níquel/química , Catálisis , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad
15.
ACS Catal ; 11(23): 14408-14416, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36237605

RESUMEN

A dinickel catalyst promotes reductive cyclization reactions of 1,1-dichloroalkenes containing pendant olefins. The reactions can be conducted with a Zn reductant or electrocatalytically using a carbon working electrode. Mechanistic studies are consistent with the intermediacy of a Ni2(vinylidene) species, which adds to the alkene and generates a metallacyclic intermediate. ß-Hydride elimination followed by C-H reductive elimination forms the cyclization product. The proposed dinickel metallacycle is structurally characterized and its stoichiometric conversion to product is demonstrated. Spin polarized, unrestricted DFT calculations are used to further examine the cyclization mechanism. These computational models reveal that both nickel centers function cooperatively to mediate the key oxidative addition, migratory insertion, ß-hydride elimination, and reductive elimination steps.

16.
Pharmacoepidemiol Drug Saf ; 30(2): 126-134, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33020970

RESUMEN

PURPOSE: To assess the prevalence and potential indications of PDE5 inhibitor use among pregnant and reproductive-age women in the United States. METHODS: We identified women 15 to 50 years with a livebirth from January 2001 through March 2018 in Sentinel Database. We assessed the prevalence of PDE5 inhibitor use prior to and during pregnancy by trimester, identified potential on- and off-label indications using predefined diagnosis codes recorded within 90 days before the estimated last menstrual period through delivery. Separately, we used data from IQVIA's National Prescription Audit and Total Patient Tracker to estimate the dispensed prescriptions for PDE5 inhibitors and the number of patients with PDE5 inhibitor prescriptions. RESULTS: We identified approximately 3.3 million pregnancies during 2001 to 2018, 96 of which had PDE5 inhibitor use during pregnancy. Prevalence of PDE5 inhibitor use was 2.61, 0.62, and 0.62 per 100, 000 live-born pregnancies during the first, second, or third trimesters, respectively. Among women exposed to a PDE5 inhibitor from 90 days before conception to the end of pregnancy, 25.0%, 31.1%, and 15.5% had a diagnosis code for fetal growth restriction, preeclampsia, and pulmonary arterial hypertension. In IQVIA data, an estimated 223, 000 prescriptions from July 2015 through June 2018 and 58, 000 women received prescriptions for PDE5 inhibitors in 2017, of whom approximately 15, 000 (26%) were aged 15 to 50 years. CONCLUSION: We found a low prevalence of PDE5 inhibitor use in pregnant and reproductive-age women. Given the very low prevalence of use and the inconsistency of neonatal mortality data across STRIDER centers, the risk to public health is low at present.


Asunto(s)
Inhibidores de Fosfodiesterasa 5 , Prescripciones , Bases de Datos Factuales , Femenino , Retardo del Crecimiento Fetal , Humanos , Recién Nacido , Embarazo , Trimestres del Embarazo , Estados Unidos/epidemiología
18.
J Am Chem Soc ; 142(16): 7598-7605, 2020 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-32250602

RESUMEN

A photoassisted Ni-catalyzed reductive cross-coupling between tosyl-protected alkyl aziridines and commercially available (hetero)aryl iodides is reported. This mild and modular method proceeds in the absence of stoichiometric heterogeneous reductants and uses an inexpensive organic photocatalyst to access medicinally valuable ß-phenethylamine derivatives. Unprecedented reactivity was achieved with the activation of cyclic aziridines. Mechanistic studies suggest that the regioselectivity and reactivity observed under these conditions are a result of nucleophilic iodide ring opening of the aziridine to generate an iodoamine as the active electrophile. This strategy also enables cross-coupling with Boc-protected aziridines.


Asunto(s)
Aziridinas/síntesis química , Yoduros/síntesis química , Fenetilaminas/química , Catálisis , Humanos , Estructura Molecular , Estereoisomerismo
19.
Pharmacoepidemiol Drug Saf ; 28(10): 1361-1368, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31410932

RESUMEN

PURPOSE: We validated an algorithm to detect frequency errors in computerized healthcare data and estimated the incidence of these errors in an integrated healthcare system. METHODS: We applied Sentinel System analytic tools on the electronic health records of Kaiser Permanente, Northern California, January 1, 2010, through May 30, 2015,to identify rheumatoid arthritis (RA) patients with new use of methotrexate (365-day baseline period). We identified potential methotrexate frequency errors using ICD-9 code 995.20 (adverse drug event), Current Procedural Terminology (CPT) code 96409 for injection of leucovorin and prescription refill patterns. We performed chart review to confirm the frequency errors, assessed performance for detecting frequency errors, and estimated the incidence of chart-confirmed errors. RESULTS: The study included 24,529 methotrexate dispensings among 3,668 RA patients. Among these, 722 (3%) had one dispensing and 23,807 (97.1%) had ≥2 dispensings during 1-year follow-up period. We flagged 653 (2.7%) with a potential medication error (46 with one dispensing and 607 with ≥2 dispensings). We sampled 94 for chart review, and confirmed three methotrexate errors. All three confirmed frequency errors involved a first methotrexate dispensing followed by injected rescue therapy, leucovorin, (positive predictive value, 60%; 95% confidence interval [CI], 15-95%). No potential errors were found among patients with ≥2 dispensings. We estimated the frequency error incidence among one methotrexate dispensing to be 0.4% (95%CI, 0.1% to 1.2%). CONCLUSION: Rescue therapy is a specific indicator of methotrexate overdose among first methotrexate dispensings. This method is generalizable to other medications with serious adverse events treated with antidotes.


Asunto(s)
Algoritmos , Antirreumáticos/efectos adversos , Sobredosis de Droga/epidemiología , Errores de Medicación/estadística & datos numéricos , Metotrexato/efectos adversos , Administración Oral , Antídotos , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , California/epidemiología , Codificación Clínica/estadística & datos numéricos , Prestación Integrada de Atención de Salud/estadística & datos numéricos , Esquema de Medicación , Sobredosis de Droga/tratamiento farmacológico , Registros Electrónicos de Salud/estadística & datos numéricos , Femenino , Humanos , Incidencia , Clasificación Internacional de Enfermedades , Leucovorina/administración & dosificación , Masculino , Errores de Medicación/efectos adversos , Metotrexato/administración & dosificación , Persona de Mediana Edad , Vigilancia de Productos Comercializados/estadística & datos numéricos
20.
Mem Cognit ; 47(2): 299-312, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30298263

RESUMEN

This study investigated the idea that semantic memory activation causes the activation of associated autobiographical memories (e.g., reading the word summer activates knowledge representations in semantic memory, as well as associated personal memories about summer in autobiographical memory). We tested this semantic-autobiographical memory priming hypothesis in three experiments. In Experiment 1, participants were primed with concepts (e.g., summer) on a familiarity task and were then given a word-cue voluntary autobiographical memory task. In support of the hypothesis, the results showed that primed participants had more autobiographical memories overlapping with the primed concepts than control participants. In Experiment 2, participants were similarly primed, but in this case they were given a measure of involuntary autobiographical memory (i.e., Schlagman and Kvavilashvili's (Memory & Cognition, 36, 920-932, 2008) vigilance task). The results of this experiment also supported the semantic-autobiographical memory-priming hypothesis. Experiment 3 ruled out an alternative possibility (i.e., that autobiographical memory processing had occurred in the word familiarity task) by showing that semantic-autobiographical priming had resulted from a priming task (lexical decision) where autobiographical memory processing was unlikely. The implications of these findings are discussed.


Asunto(s)
Señales (Psicología) , Memoria Episódica , Recuerdo Mental/fisiología , Reconocimiento en Psicología/fisiología , Semántica , Adulto , Humanos , Adulto Joven
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