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1.
Cell ; 178(1): 152-159.e11, 2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31178121

RESUMEN

Intrinsic and acquired drug resistance and induction of secondary malignancies limit successful chemotherapy. Because mutagenic translesion synthesis (TLS) contributes to chemoresistance as well as treatment-induced mutations, targeting TLS is an attractive avenue for improving chemotherapeutics. However, development of small molecules with high specificity and in vivo efficacy for mutagenic TLS has been challenging. Here, we report the discovery of a small-molecule inhibitor, JH-RE-06, that disrupts mutagenic TLS by preventing recruitment of mutagenic POL ζ. Remarkably, JH-RE-06 targets a nearly featureless surface of REV1 that interacts with the REV7 subunit of POL ζ. Binding of JH-RE-06 induces REV1 dimerization, which blocks the REV1-REV7 interaction and POL ζ recruitment. JH-RE-06 inhibits mutagenic TLS and enhances cisplatin-induced toxicity in cultured human and mouse cell lines. Co-administration of JH-RE-06 with cisplatin suppresses the growth of xenograft human melanomas in mice, establishing a framework for developing TLS inhibitors as a novel class of chemotherapy adjuvants.


Asunto(s)
Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Mutagénesis/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Quinolinas/uso terapéutico , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisplatino/efectos adversos , Cisplatino/farmacología , Daño del ADN/efectos de los fármacos , ADN Polimerasa Dirigida por ADN , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Proteínas Mad2/metabolismo , Ratones , Ratones Desnudos , Ratones Transgénicos , Neoplasias/metabolismo , Neoplasias/patología , Nucleotidiltransferasas/antagonistas & inhibidores , Nucleotidiltransferasas/química , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Quinolinas/química , Quinolinas/farmacología , Transfección , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Cell ; 177(6): 1649-1661.e9, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-31080069

RESUMEN

Current machine learning techniques enable robust association of biological signals with measured phenotypes, but these approaches are incapable of identifying causal relationships. Here, we develop an integrated "white-box" biochemical screening, network modeling, and machine learning approach for revealing causal mechanisms and apply this approach to understanding antibiotic efficacy. We counter-screen diverse metabolites against bactericidal antibiotics in Escherichia coli and simulate their corresponding metabolic states using a genome-scale metabolic network model. Regression of the measured screening data on model simulations reveals that purine biosynthesis participates in antibiotic lethality, which we validate experimentally. We show that antibiotic-induced adenine limitation increases ATP demand, which elevates central carbon metabolism activity and oxygen consumption, enhancing the killing effects of antibiotics. This work demonstrates how prospective network modeling can couple with machine learning to identify complex causal mechanisms underlying drug efficacy.


Asunto(s)
Antibacterianos/metabolismo , Antibacterianos/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Adenina/metabolismo , Biología Computacional/métodos , Evaluación Preclínica de Medicamentos/métodos , Escherichia coli/metabolismo , Aprendizaje Automático , Redes y Vías Metabólicas/inmunología , Modelos Teóricos , Purinas/metabolismo
3.
Nat Immunol ; 19(10): 1100-1111, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30250184

RESUMEN

Females have an overall advantage over males in resisting Gram-negative bacteremias, thus hinting at sexual dimorphism of immunity during infections. Here, through intravital microscopy, we observed a sex-biased difference in the capture of blood-borne bacteria by liver macrophages, a process that is critical for the clearance of systemic infections. Complement opsonization was indispensable for the capture of enteropathogenic Escherichia coli (EPEC) in male mice; however, a faster complement component 3-independent process involving abundant preexisting antibodies to EPEC was detected in female mice. These antibodies were elicited predominantly in female mice at puberty in response to estrogen regardless of microbiota-colonization conditions. Estrogen-driven antibodies were maternally transferrable to offspring and conferred protection during infancy. These antibodies were conserved in humans and recognized specialized oligosaccharides integrated into the bacterial lipopolysaccharide and capsule. Thus, an estrogen-driven, innate antibody-mediated immunological strategy conferred protection to females and their offspring.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Infecciones por Escherichia coli/inmunología , Inmunidad Innata/inmunología , Caracteres Sexuales , Animales , Escherichia coli Enteropatógena , Estrógenos/inmunología , Femenino , Humanos , Lactante , Macrófagos del Hígado/inmunología , Masculino , Intercambio Materno-Fetal/inmunología , Ratones , Embarazo
5.
Proc Natl Acad Sci U S A ; 120(31): e2308798120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487074

RESUMEN

Mammalian infants depend on parental care for survival, with numerous consequences for their behavioral development. We investigated the epigenetic and neurodevelopmental mechanisms mediating the impact of early biparental care on development of alloparenting behavior, or caring for offspring that are not one's own. We find that receiving high parental care early in life leads to slower epigenetic aging of both sexes and widespread male-specific differential expression of genes related to synaptic transmission and autism in the nucleus accumbens. Examination of parental care composition indicates that high-care fathers promote a male-specific increase in excitatory synapses and increases in pup retrieval behavior as juveniles. Interestingly, females raised by high-care fathers have the opposite behavioral response and display fewer pup retrievals. These results support the concept that neurodevelopmental trajectories are programmed by different features of early-life parental care and reveal that male neurodevelopmental processes are uniquely sensitive to care by fathers.


Asunto(s)
Conducta Animal , Padre , Humanos , Femenino , Animales , Masculino , Conducta Animal/fisiología , Conducta Materna/fisiología , Núcleo Accumbens , Padres , Conducta Paterna , Arvicolinae/fisiología
6.
J Biol Chem ; 299(2): 102859, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36592930

RESUMEN

Translesion synthesis (TLS) DNA polymerase Polζ is crucial for the bypass replication over sites of DNA damage. The Rev7 subunit of Polζ is a HORMA (Hop1, Rev7, Mad2) protein that facilitates recruitment of Polζ to the replication fork via interactions with the catalytic subunit Rev3 and the translesion synthesis scaffold protein Rev1. Human Rev7 (hRev7) interacts with two Rev7-binding motifs (RBMs) of hRev3 by a mechanism conserved among HORMA proteins whereby the safety-belt loop of hRev7 closes on the top of the ligand. The two copies of hRev7 tethered by the two hRev3-RBMs form a symmetric head-to-head dimer through the canonical HORMA dimerization interface. Recent cryo-EM structures reveal that Saccharomyces cerevisiae Polζ (scPolζ) also includes two copies of scRev7 bound to distinct regions of scRev3. Surprisingly, the HORMA dimerization interface is not conserved in scRev7, with the two scRev7 protomers forming an asymmetric head-to-tail dimer with a much smaller interface than the hRev7 dimer. Here, we validated the two adjacent RBM motifs in scRev3, which bind scRev7 with affinities that differ by two orders of magnitude and confirmed the 2:1 stoichiometry of the scRev7:Rev3 complex in solution. However, our biophysical studies reveal that scRev7 does not form dimers in solution either on its own accord or when tethered by the two RBMs in scRev3. These findings imply that the scRev7 dimer observed in the cryo-EM structures is induced by scRev7 interactions with other Polζ subunits and that Rev7 homodimerization via the HORMA interface is a mechanism that emerged later in evolution.


Asunto(s)
Replicación del ADN , ADN Polimerasa Dirigida por ADN , Humanos , Daño del ADN , Reparación del ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Proteínas Mad2/química , Proteínas Mad2/metabolismo , Nucleotidiltransferasas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
7.
Circulation ; 147(15): e676-e698, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-36912134

RESUMEN

Acute atrial fibrillation is defined as atrial fibrillation detected in the setting of acute care or acute illness; atrial fibrillation may be detected or managed for the first time during acute hospitalization for another condition. Atrial fibrillation after cardiothoracic surgery is a distinct type of acute atrial fibrillation. Acute atrial fibrillation is associated with high risk of long-term atrial fibrillation recurrence, warranting clinical attention during acute hospitalization and over long-term follow-up. A framework of substrates and triggers can be useful for evaluating and managing acute atrial fibrillation. Acute management requires a multipronged approach with interdisciplinary care collaboration, tailoring treatments to the patient's underlying substrate and acute condition. Key components of acute management include identification and treatment of triggers, selection and implementation of rate/rhythm control, and management of anticoagulation. Acute rate or rhythm control strategy should be individualized with consideration of the patient's capacity to tolerate rapid rates or atrioventricular dyssynchrony, and the patient's ability to tolerate the risk of the therapeutic strategy. Given the high risks of atrial fibrillation recurrence in patients with acute atrial fibrillation, clinical follow-up and heart rhythm monitoring are warranted. Long-term management is guided by patient substrate, with implications for intensity of heart rhythm monitoring, anticoagulation, and considerations for rhythm management strategies. Overall management of acute atrial fibrillation addresses substrates and triggers. The 3As of acute management are acute triggers, atrial fibrillation rate/rhythm management, and anticoagulation. The 2As and 2Ms of long-term management include monitoring of heart rhythm and modification of lifestyle and risk factors, in addition to considerations for atrial fibrillation rate/rhythm management and anticoagulation. Several gaps in knowledge related to acute atrial fibrillation exist and warrant future research.


Asunto(s)
Fibrilación Atrial , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/terapia , American Heart Association , Antiarrítmicos/uso terapéutico , Anticoagulantes/uso terapéutico , Anticoagulantes/farmacología , Hospitalización , Frecuencia Cardíaca
8.
J Am Chem Soc ; 146(12): 8508-8519, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38382542

RESUMEN

Tricomponent cobalt(salen)-catalyzed carbofunctionalization of unsaturated substrates by radical-polar crossover has the potential to streamline access to broad classes of heteroatom-functionalized synthetic targets, yet the reaction platform has remained elusive, despite the well-developed analogous hydrofunctionalizations mediated by high-valent alkylcobalt intermediates. We report herein the development of a cobalt(salen) catalytic system that enables carbofunctionalization. The reaction entails a tricomponent decarboxylative 1,4-carboamination of dienes and provides a direct route to aromatic allylic amines by obviating preformed allylation reagents and protection of oxidation-sensitive aromatic amines. The catalytic system merges acridine photocatalysis with cobalt(salen)-catalyzed regioselective 1,4-carbofunctionalization that facilitates the crossover of the radical and polar phases of the tricomponent coupling process, revealing critical roles of the reactants, as well as ligand effects and the nature of the formal high-valent alkylcobalt species on the chemo- and regioselectivity.

9.
Emerg Infect Dis ; 30(2): 388-391, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38217064

RESUMEN

We devised a model to interpret discordant SARS-CoV-2 test results. We estimate that, during March 2020-May 2022, a patient in the United States who received a positive rapid antigen test result followed by a negative nucleic acid test result had only a 15.4% (95% CI 0.6%-56.7%) chance of being infected.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Estados Unidos/epidemiología , COVID-19/diagnóstico , Prueba de COVID-19 , Pruebas Diagnósticas de Rutina , Sensibilidad y Especificidad
10.
Nat Rev Neurosci ; 20(9): 514-532, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31289380

RESUMEN

Light-controllable tools provide powerful means to manipulate and interrogate brain function with relatively low invasiveness and high spatiotemporal precision. Although optogenetic approaches permit neuronal excitation or inhibition at the network level, other technologies, such as optopharmacology (also known as photopharmacology) have emerged that provide molecular-level control by endowing light sensitivity to endogenous biomolecules. In this Review, we discuss the challenges and opportunities of photocontrolling native neuronal signalling pathways, focusing on ion channels and neurotransmitter receptors. We describe existing strategies for rendering receptors and channels light sensitive and provide an overview of the neuroscientific insights gained from such approaches. At the crossroads of chemistry, protein engineering and neuroscience, optopharmacology offers great potential for understanding the molecular basis of brain function and behaviour, with promises for future therapeutics.


Asunto(s)
Canales Iónicos/metabolismo , Neuronas/metabolismo , Optogenética/tendencias , Procesos Fotoquímicos , Receptores Acoplados a Proteínas G/metabolismo , Animales , Humanos , Activación del Canal Iónico/efectos de los fármacos , Activación del Canal Iónico/fisiología , Canales Iónicos/antagonistas & inhibidores , Canales Iónicos/química , Moduladores del Transporte de Membrana/farmacología , Neuronas/química , Neuronas/efectos de los fármacos , Optogenética/métodos , Procesos Fotoquímicos/efectos de los fármacos , Receptores Acoplados a Proteínas G/química
11.
Am J Obstet Gynecol ; 230(3): 340.e1-340.e13, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37863158

RESUMEN

BACKGROUND: Opioids are routinely prescribed for postoperative pain control after gynecologic surgery with growing evidence showing that most prescribed opioids go unused. Restrictive opioid prescribing has been implemented in other surgical specialties to combat the risk for opioid misuse and diversion. The impact of this practice in the urogynecologic patient population is unknown. OBJECTIVE: This study aimed to determine if a restrictive opioid prescription protocol is noninferior to routine opioid prescribing in terms of patient satisfaction with pain control after minor and major surgeries for prolapse and incontinence. STUDY DESIGN: This was a single-center, randomized, noninferiority trial of opioid-naïve patients who underwent minor (eg, colporrhaphy or mid-urethral sling) or major (eg, vaginal or minimally invasive abdominal prolapse repair) urogynecologic surgery. Patients were excluded if they had contraindications to all multimodal analgesia and if they scored ≥30 on the Pain Catastrophizing Scale. Subjects were randomized on the day of surgery to the standard opioid prescription protocol (wherein patients routinely received an opioid prescription upon discharge [ie, 3-10 tablets of 5 mg oxycodone]) or to the restrictive protocol (no opioid prescription unless the patient requested one). All patients received multimodal pain medications. Participants and caregivers were not blinded. Subjects were asked to record their pain medication use and pain levels for 7 days. The primary outcome was satisfaction with pain control reported at the 6-week postoperative visit. We hypothesized that patient satisfaction with the restrictive protocol would be noninferior to those randomized to the standard protocol. The noninferiority margin was 15 percentage points. Pain level scores, opioid usage, opioid prescription refills, and healthcare use were secondary outcomes assessed for superiority. RESULTS: A total of 133 patients were randomized, and 127 (64 in the standard arm and 63 in the restrictive arm) completed the primary outcome evaluation and were included in the analysis. There were no statistically significant differences between the study groups, and this remained after adjusting for the surgery type. Major urogynecologic surgery was performed in 73.6% of the study population, and minor surgery was performed in 26.4% of the population. Same-day discharge occurred for 87.6% of all subjects. Patient satisfaction was 92.2% in the standard protocol arm and 92.1% in the restrictive protocol arm (difference, -0.1%; P=.004), which met the criterion for noninferiority. No opioid usage in the first 7 days after hospital discharge was reported by 48.4% of the patients in the standard protocol arm and by 70.8% in the restrictive protocol arm (P=.009). Opioid prescription refills occurred in 8.5% of patients with no difference between the study groups (9.4% in the standard arm vs 6.7% in the restrictive arm; P=.661). No difference was seen in the rate of telephone calls and urgent visits for pain control between the study arms. CONCLUSION: Among women who underwent minor and major surgery for prolapse and incontinence, patient satisfaction rates were noninferior after restrictive opioid prescribing when compared with routine opioid prescribing.


Asunto(s)
Analgésicos Opioides , Prolapso de Órgano Pélvico , Humanos , Femenino , Analgésicos Opioides/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Pautas de la Práctica en Medicina , Oxicodona/uso terapéutico , Prolapso de Órgano Pélvico/cirugía
12.
PLoS Comput Biol ; 19(6): e1011149, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37262052

RESUMEN

COVID-19 has disproportionately impacted individuals depending on where they live and work, and based on their race, ethnicity, and socioeconomic status. Studies have documented catastrophic disparities at critical points throughout the pandemic, but have not yet systematically tracked their severity through time. Using anonymized hospitalization data from March 11, 2020 to June 1, 2021 and fine-grain infection hospitalization rates, we estimate the time-varying burden of COVID-19 by age group and ZIP code in Austin, Texas. During this 15-month period, we estimate an overall 23.7% (95% CrI: 22.5-24.8%) infection rate and 29.4% (95% CrI: 28.0-31.0%) case reporting rate. Individuals over 65 were less likely to be infected than younger age groups (11.2% [95% CrI: 10.3-12.0%] vs 25.1% [95% CrI: 23.7-26.4%]), but more likely to be hospitalized (1,965 per 100,000 vs 376 per 100,000) and have their infections reported (53% [95% CrI: 49-57%] vs 28% [95% CrI: 27-30%]). We used a mixed effect poisson regression model to estimate disparities in infection and reporting rates as a function of social vulnerability. We compared ZIP codes ranking in the 75th percentile of vulnerability to those in the 25th percentile, and found that the more vulnerable communities had 2.5 (95% CrI: 2.0-3.0) times the infection rate and only 70% (95% CrI: 60%-82%) the reporting rate compared to the less vulnerable communities. Inequality persisted but declined significantly over the 15-month study period. Our results suggest that further public health efforts are needed to mitigate local COVID-19 disparities and that the CDC's social vulnerability index may serve as a reliable predictor of risk on a local scale when surveillance data are limited.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Etnicidad , Hospitalización , Salud Pública
13.
J Arthroplasty ; 39(9): 2329-2335.e1, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38582372

RESUMEN

BACKGROUND: Online resources are important for patient self-education and reflect public interest. We described commonly asked questions regarding the direct anterior versus posterior approach (DAA, PA) to total hip arthroplasty (THA) and the quality of associated websites. METHODS: We extracted the top 200 questions and websites in Google's "People Also Ask" section for 8 queries on January 8, 2023, and grouped websites and questions into DAA, PA, or comparison. Questions were categorized using Rothwell's classification (fact, policy, value) and THA-relevant subtopics. Websites were evaluated by information source, Journal of the American Medical Association Benchmark Criteria (credibility), DISCERN survey (information quality), and readability. RESULTS: We included 429 question/website combinations (questions: 52.2% DAA, 21.2% PA, 26.6% comparison; websites: 39.0% DAA, 11.0% PA, 9.6% comparison). Per Rothwell's classification, 56.2% of questions were fact, 31.7% value, 10.0% policy, and 2.1% unrelated. The THA-specific question subtopics differed between DAA and PA (P < .001), specifically for recovery timeline (DAA 20.5%, PA 37.4%), indications/management (DAA 13.4%, PA 1.1%), and technical details (DAA 13.8%, PA 5.5%). Information sources differed between DAA (61.7% medical practice/surgeon) and PA websites (44.7% government; P < .001). The median Journal of the American Medical Association Benchmark score was 1 (limited credibility, interquartile range 1 to 2), with the lowest scores for DAA websites (P < .001). The median DISCERN score was 55 ("good" quality, interquartile range 43 to 65), with the highest scores for comparison websites (P < .001). Median Flesch-Kincaid Grade Level scores were 12th grade level for both DAA and PA (P = .94). CONCLUSIONS: Patients' informational interests can guide counseling. Internet searches that explicitly compare THA approaches yielded websites that provide higher-quality information. Providers may also advise patients that physician websites and websites only describing the DAA may have less balanced perspectives, and limited information regarding surgical approaches is available from social media resources.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Internet , Humanos
14.
J Craniofac Surg ; 35(5): 1389-1393, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38738872

RESUMEN

BACKGROUND: Facial feminization surgeries are important gender-affirming procedures for transfeminine individuals. The literature provides guidance on classically feminine facial features but the aesthetic preferences of transgender patients have not been studied. This study aimed to define the preferred feminine facial proportions of transfeminine patients and compare them to a mixed population of US adults. METHODS: An online survey was designed consisting of virtually modified images with progressive degrees of change in 6 facial features: forehead, nasal dorsum, chin projection, nasolabial angle, mandibular angle, and chin height. It was administered to transfeminine patients in a large-scale health system as well as the general population using an online market research instrument. Respondents ranked each image on a 7-point Likert scale from "very unattractive" to "very attractive" for a feminine face. RESULTS: Both groups agreed that a moderately convex forehead without supraorbital ridge prominence, slightly sloped nasal dorsum, ∼105-degree nasolabial angle, and decreased chin height were considered most attractive. In addition, very concave nasal slope and ∼110-degree nasolabial angle were rated significantly higher by transfeminine respondents compared with controls. The most classically masculine versions of each feature were considered significantly more unattractive by transfeminine patients when compared with controls. CONCLUSION: Transfeminine individuals share significant preferences in feminine facial features with control respondents. However, transfeminine patients were more averse to traditionally masculine features on a feminine face and more accepting of the most traditionally feminine versions of nasal contours. Understanding these differences can facilitate surgical planning between surgeons and patients and potentially improve patient satisfaction.


Asunto(s)
Estética , Cara , Personas Transgénero , Humanos , Femenino , Adulto , Masculino , Cara/anatomía & histología , Encuestas y Cuestionarios , Prioridad del Paciente , Persona de Mediana Edad , Cirugía de Reasignación de Sexo/métodos
15.
Pediatr Emerg Care ; 40(1): 76-81, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37011228

RESUMEN

OBJECTIVES: Emergency medicine (EM) confers a high risk of burnout that may be exacerbated by the COVID-19 pandemic. We aimed to determine the longitudinal prevalence of burnout in pediatric EM (PEM) physicians/fellows working in tertiary PEM departments across Canada and its fluctuation during the pandemic. METHODS: A national mixed-methods survey using a validated 2-question proxy for burnout was distributed monthly through 9 months. The primary outcome was the trajectory in probability of burnout, which was examined as both emotional exhaustion (EE) and depersonalization (DP), EE alone, and DP alone. Secondary outcomes investigated burnout and its association with demographic variables. Quantitative data were analyzed using logistic regression for primary outcomes and subanalyses for secondary outcomes. Conventional content analysis was used to analyze qualitative data and generate themes. RESULTS: From February to October 2021, 92 of 98 respondents completed at least 1 survey, 78% completed at least 3 consecutive surveys, and 48% completed at least 6 consecutive surveys. Predicted probability of EE was bimodal with peaks in May (25%) and October (22%) 2021. Rates of DP alone or having both EE and DP were approximately 1% and stable over the study period. Mid-career physicians were at lower risk of EE (odds ratio, 0.02; 95% confidence interval, 0-0.22) compared with early-career physicians. Underlying drivers of burnout were multifaceted. CONCLUSIONS: Our study suggests that increased COVID-19 case burden was correlated with EE levels during the third and fourth waves of the pandemic. Emotional exhaustion was worsened by systemic factors, and interventions must target common themes of unsustainable workloads and overwhelming lack of control.


Asunto(s)
Agotamiento Profesional , COVID-19 , Médicos , Humanos , Niño , Pandemias , COVID-19/epidemiología , Prevalencia , Médicos/psicología , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Agotamiento Emocional , Encuestas y Cuestionarios
16.
Angew Chem Int Ed Engl ; : e202408745, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264815

RESUMEN

Organoboron compounds are widely utilized in organic synthesis for their diverse reactivity, modular preparation, and stability compared to other classes of organometallic reagents. While organoboron species are commonly employed as nucleophiles in cross-coupling reactions, their potential as racemic building blocks in enantioconvergent transformations remains largely untapped. Herein, we demonstrate the direct utilization of alkylboronic pinacol esters in intermolecular enantioconvergent transformations. Specifically, this work describes the development and mechanistic study of an enantioconvergent deborylative cyanation enabled by Cu catalysis. This method imparts a high degree of enantioselectivity and tolerates a wide range of common functional groups and heterocycles. The reaction is proposed to proceed through a radical-relay mechanism. Aniline-assisted homolysis of the carbon-boron bond results in prochiral alkyl radicals that are functionalized by in situ generated Cu(II)(CN)2 species in an enantioselective fashion. The Cu(II)(CN)2 intermediate was characterized by electron paramagnetic resonance (EPR) spectroscopy, and its electronic structure was probed using density functional theory (DFT) calculations. Computational studies were carried out to corroborate the proposed radical-relay mechanism.

17.
Angew Chem Int Ed Engl ; 63(13): e202315726, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38329885

RESUMEN

We have developed a photochemical protecting group that enables wavelength selective uncaging using green versus violet light. Change of the exocyclic oxygen of the laser dye coumarin-102 to sulfur, gave thio-coumarin-102, a new chromophore with an absorption ratio at 503/402 nm of 37. Photolysis of thio-coumarin-102 caged γ-aminobutyric acid was found to be highly wavelength selective on neurons, with normalized electrical responses >100-fold higher in the green versus violet channel. When partnered with coumarin-102 caged glutamate, we could use whole cell violet and green irradiation to fire and block neuronal action potentials with complete orthogonality. Localized irradiation of different dendritic segments, each connected to a neuronal cell body, in concert with 3-dimenional Ca2+ imaging, revealed that such inputs could function independently. Chemical signaling in living cells always involves a complex balance of multiple pathways, use of (thio)-coumarin-102 caged compounds will enable arbitrarily timed flashes of green and violet light to interrogate two independent pathways simultaneously.


Asunto(s)
Luz Verde , Neuronas , Neuronas/metabolismo , Fotólisis , Cumarinas/química , Ácido Glutámico/metabolismo
18.
Circulation ; 146(6): e50-e68, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35862152

RESUMEN

The use of temporary mechanical circulatory support in cardiogenic shock has increased dramatically despite a lack of randomized controlled trials or evidence guiding clinical decision-making. Recommendations from professional societies on temporary mechanical circulatory support escalation and de-escalation are limited. This scientific statement provides pragmatic suggestions on temporary mechanical circulatory support device selection, escalation, and weaning strategies in patients with common cardiogenic shock causes such as acute decompensated heart failure and acute myocardial infarction. The goal of this scientific statement is to serve as a resource for clinicians making temporary mechanical circulatory support management decisions and to propose standardized approaches for their use until more robust randomized clinical data are available.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Insuficiencia Cardíaca , Corazón Auxiliar , American Heart Association , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Humanos , Contrapulsador Intraaórtico/efectos adversos , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/etiología , Choque Cardiogénico/terapia
19.
J Am Chem Soc ; 145(24): 13059-13068, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37294869

RESUMEN

One of the most important reactions of 1,2,3-triazines with a dienophile is inverse electron demand Diels-Alder (IEDDA) cycloaddition, which occurs through nucleophilic addition to the triazine followed by N2 loss and cyclization to generate a heterocycle. The site of addition is either at the 4- or 6-position of the symmetrically substituted triazine core. Although specific examples of the addition of nucleophiles to triazines are known, a comprehensive understanding has not been reported, and the preferred site for nucleophilic addition is unknown and unexplored. With access to unsymmetrical 1,2,3-triazine-1-oxides and their deoxygenated 1,2,3-triazine compounds, we report C-, N-, H-, O-, and S-nucleophilic additions on 1,2,3-triazine and 1,2,3-triazine-1-oxide frameworks where the 4- and 6-positions could be differentiated. In the IEDDA cycloadditions using C- and N-nucleophiles, the site of addition is at C-6 for both heterocyclic systems, but product formation with 1,2,3-triazine-1-oxides is faster. Other N-nucleophile reactions with triazine 1-oxides show addition at either the 4- or 6-position of the triazine 1-oxide ring, but nucleophilic attack only occurs at the 6-position on the triazine. Hydride from NaBH4 undergoes addition at the 6-position on the triazine and the triazine 1-oxide core. Alkoxides show a high nucleophilic selectivity for the 4-position of the triazine 1-oxide. Thiophenoxide, cysteine, and glutathione undergo nucleophilic addition on the triazine core at the 6-position, while addition occurs at the 4-position of the triazine 1-oxide. These nucleophilic additions proceed under mild reaction conditions and show high functional group tolerance. Computational studies clarified the roles of the nucleophilic addition and nitrogen extrusion steps and the influence of steric and electronic factors in determining the outcomes of the reactions with different nucleophiles.

20.
Clin Immunol ; 251: 109629, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37149117

RESUMEN

The objective of this study was to characterize the complement-inhibiting activity of SAR445088, a novel monoclonal antibody specific for the active form of C1s. Wieslab® and hemolytic assays were used to demonstrate that SAR445088 is a potent, selective inhibitor of the classical pathway of complement. Specificity for the active form of C1s was confirmed in a ligand binding assay. Finally, TNT010 (a precursor to SAR445088) was assessed in vitro for its ability to inhibit complement activation associated with cold agglutinin disease (CAD). TNT010 inhibited C3b/iC3b deposition on human red blood cells incubated with CAD patient serum and decreased their subsequent phagocytosis by THP-1 cells. In summary, this study identifies SAR445088 as a potential therapeutic for the treatment of classical pathway-driven diseases and supports its continued assessment in clinical trials.


Asunto(s)
Anemia Hemolítica Autoinmune , Complemento C1s , Humanos , Complemento C1s/metabolismo , Activación de Complemento , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Inactivadores del Complemento/uso terapéutico , Vía Clásica del Complemento
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