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1.
Am J Hum Genet ; 111(5): 833-840, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38701744

RESUMEN

Some commercial firms currently sell polygenic indexes (PGIs) to individual consumers, despite their relatively low predictive power. It might be tempting to assume that because the predictive power of many PGIs is so modest, other sorts of firms-such as those selling insurance and financial services-will not be interested in using PGIs for their own purposes. We argue to the contrary. We build this argument in two ways. First, we offer a very simple model, rooted in economic theory, of a profit-maximizing firm that can gain information about a single consumer's genome. We use the model to show that, depending on the specific economic environment, a firm would be willing to pay for statistically noisy PGIs, even if they allow for only a small reduction in uncertainty. Second, we describe two plausible scenarios in which these different kinds of firms could conceivably use PGIs to maximize profits. Finally, we briefly discuss some of the associated ethics and policy issues. They deserve more attention, which is unlikely to be given until it is first recognized that firms whose services affect a large swath of the public will indeed have incentives to use PGIs.


Asunto(s)
Herencia Multifactorial , Humanos , Pruebas Genéticas/ética , Pruebas Genéticas/economía , Herencia Multifactorial/genética
2.
PLoS Genet ; 20(3): e1011188, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38442125

RESUMEN

Bacteria have evolved complex transcriptional regulatory networks, as well as many diverse regulatory strategies at the RNA level, to enable more efficient use of metabolic resources and a rapid response to changing conditions. However, most RNA-based regulatory mechanisms are not well conserved across different bacterial species despite controlling genes important for virulence or essential biosynthetic processes. Here, we characterize the activity of, and assess the fitness benefit conferred by, twelve cis-acting regulatory RNAs (including several riboswitches and a T-box), in the opportunistic pathogen Streptococcus pneumoniae TIGR4. By evaluating native locus mutants of each regulator that result in constitutively active or repressed expression, we establish that growth defects in planktonic culture are associated with constitutive repression of gene expression, while constitutive activation of gene expression is rarely deleterious. In contrast, in mouse nasal carriage and pneumonia models, strains with either constitutively active and repressed gene expression are significantly less fit than matched control strains. Furthermore, two RNA-regulated pathways, FMN synthesis/transport and pyrimidine synthesis/transport display exceptional sensitivity to mis-regulation or constitutive gene repression in both planktonic culture and in vivo environments. Thus, despite lack of obvious phenotypes associated with constitutive gene expression in vitro, the fitness benefit conferred on bacteria via fine-tuned metabolic regulation through cis-acting regulatory RNAs is substantial in vivo, and therefore easily sufficient to drive the evolution and maintenance of diverse RNA regulatory mechanisms.


Asunto(s)
ARN , Streptococcus pneumoniae , Animales , Ratones , Streptococcus pneumoniae/genética , ARN/metabolismo , Virulencia/genética , Fenotipo , Regulación Bacteriana de la Expresión Génica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(33): e2302491120, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37556500

RESUMEN

Traditionally, scientists have placed more emphasis on communicating inferential uncertainty (i.e., the precision of statistical estimates) compared to outcome variability (i.e., the predictability of individual outcomes). Here, we show that this can lead to sizable misperceptions about the implications of scientific results. Specifically, we present three preregistered, randomized experiments where participants saw the same scientific findings visualized as showing only inferential uncertainty, only outcome variability, or both and answered questions about the size and importance of findings they were shown. Our results, composed of responses from medical professionals, professional data scientists, and tenure-track faculty, show that the prevalent form of visualizing only inferential uncertainty can lead to significant overestimates of treatment effects, even among highly trained experts. In contrast, we find that depicting both inferential uncertainty and outcome variability leads to more accurate perceptions of results while appearing to leave other subjective impressions of the results unchanged, on average.

4.
Brief Bioinform ; 24(3)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-36951499

RESUMEN

Riboswitches are conserved structural ribonucleic acid (RNA) sensors that are mainly found to regulate a large number of genes/operons in bacteria. Presently, >50 bacterial riboswitch classes have been discovered, but only the thiamine pyrophosphate riboswitch class is detected in a few eukaryotes like fungi, plants and algae. One of the most important challenges in riboswitch research is to discover existing riboswitch classes in eukaryotes and to understand the evolution of bacterial riboswitches. However, traditional search methods for riboswitch detection have failed to detect eukaryotic riboswitches besides just one class and any distant structural homologs of riboswitches. We developed a novel approach based on inverse RNA folding that attempts to find sequences that match the shape of the target structure with minimal sequence conservation based on key nucleotides that interact directly with the ligand. Then, to support our matched candidates, we expanded the results into a covariance model representing similar sequences preserving the structure. Our method transforms a structure-based search into a sequence-based search that considers the conservation of secondary structure shape and ligand-binding residues. This method enables us to identify a potential structural candidate in fungi that could be the distant homolog of bacterial purine riboswitches. Further, phylogenomic analysis and evolutionary distribution of this structural candidate indicate that the most likely point of origin of this structural candidate in these organisms is associated with the loss of traditional purine riboswitches. The computational approach could be applicable to other domains and problems in RNA research.


Asunto(s)
Riboswitch , Riboswitch/genética , Pliegue del ARN , ARN , Ligandos , Bacterias/genética , Hongos/genética , Purinas , ARN Bacteriano/genética , Conformación de Ácido Nucleico
5.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35105809

RESUMEN

Encouraging vaccination is a pressing policy problem. To assess whether text-based reminders can encourage pharmacy vaccination and what kinds of messages work best, we conducted a megastudy. We randomly assigned 689,693 Walmart pharmacy patients to receive one of 22 different text reminders using a variety of different behavioral science principles to nudge flu vaccination or to a business-as-usual control condition that received no messages. We found that the reminder texts that we tested increased pharmacy vaccination rates by an average of 2.0 percentage points, or 6.8%, over a 3-mo follow-up period. The most-effective messages reminded patients that a flu shot was waiting for them and delivered reminders on multiple days. The top-performing intervention included two texts delivered 3 d apart and communicated to patients that a vaccine was "waiting for you." Neither experts nor lay people anticipated that this would be the best-performing treatment, underscoring the value of simultaneously testing many different nudges in a highly powered megastudy.


Asunto(s)
Programas de Inmunización , Vacunas contra la Influenza/administración & dosificación , Farmacias , Vacunación/métodos , Anciano , COVID-19 , Femenino , Humanos , Gripe Humana/prevención & control , Masculino , Persona de Mediana Edad , Farmacias/estadística & datos numéricos , Sistemas Recordatorios , Envío de Mensajes de Texto , Vacunación/estadística & datos numéricos
6.
Am J Epidemiol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38957970

RESUMEN

In longitudinal studies, the devices used to measure exposures can change from visit to visit. Calibration studies, wherein a subset of participants is measured using both devices at follow-up, may be used to assess between-device differences (i.e., errors). Then, statistical methods are needed to adjust for between-device differences and the missing measurement data that often appear in calibration studies. Regression calibration and multiple imputation are two possible methods. We compared both methods in linear regression with a simulation study, considering various real-world scenarios for a longitudinal study of pulse wave velocity. Regression calibration and multiple imputation were both essentially unbiased, but correctly estimating the standard errors posed challenges. Multiple imputation with predicted mean matching produced close agreement with the empirical standard error. Fully stochastic multiple imputation underestimated the standard error by up to 50%, and regression calibration with bootstrapped standard errors performed slightly better than fully stochastic multiple imputation. Regression calibration was slightly more efficient than either multiple imputation method. The results suggest use of multiple imputation with predictive mean matching over fully stochastic imputation or regression calibration in longitudinal studies where a new device at follow-up might be error-prone compared to the device used at baseline.

7.
N Engl J Med ; 385(1): 78-86, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34192436

RESUMEN

Companies have recently begun to sell a new service to patients considering in vitro fertilization: embryo selection based on polygenic scores (ESPS). These scores represent individualized predictions of health and other outcomes derived from genomewide association studies in adults to partially predict these outcomes. This article includes a discussion of many factors that lower the predictive power of polygenic scores in the context of embryo selection and quantifies these effects for a variety of clinical and nonclinical traits. Also discussed are potential unintended consequences of ESPS (including selecting for adverse traits, altering population demographics, exacerbating inequalities in society, and devaluing certain traits). Recommendations for the responsible communication about ESPS by practitioners are provided, and a call for a society-wide conversation about this technology is made. (Funded by the National Institute on Aging and others.).


Asunto(s)
Embrión de Mamíferos , Fertilización In Vitro , Pruebas Genéticas , Variación Genética , Herencia Multifactorial/genética , Fenotipo , Diagnóstico Preimplantación , Escolaridad , Interacción Gen-Ambiente , Estudio de Asociación del Genoma Completo , Humanos , Valor Predictivo de las Pruebas
8.
J Pediatr ; 269: 113973, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38401785

RESUMEN

OBJECTIVE: To test whether different clinical decision support tools increase clinician orders and patient completions relative to standard practice and each other. STUDY DESIGN: A pragmatic, patient-randomized clinical trial in the electronic health record was conducted between October 2019 and April 2020 at Geisinger Health System in Pennsylvania, with 4 arms: care gap-a passive listing recommending screening; alert-a panel promoting and enabling lipid screen orders; both; and a standard practice-no guideline-based notification-control arm. Data were analyzed for 13 346 9- to 11-year-old patients seen within Geisinger primary care, cardiology, urgent care, or nutrition clinics, or who had an endocrinology visit. Principal outcomes were lipid screening orders by clinicians and completions by patients within 1 week of orders. RESULTS: Active (care gap and/or alert) vs control arm patients were significantly more likely (P < .05) to have lipid screening tests ordered and completed, with ORs ranging from 1.67 (95% CI 1.28-2.19) to 5.73 (95% CI 4.46-7.36) for orders and 1.54 (95% CI 1.04-2.27) to 2.90 (95% CI 2.02-4.15) for completions. Alerts, with or without care gaps listed, outperformed care gaps alone on orders, with odds ratios ranging from 2.92 (95% CI 2.32-3.66) to 3.43 (95% CI 2.73-4.29). CONCLUSIONS: Electronic alerts can increase lipid screening orders and completions, suggesting clinical decision support can improve guideline-concordant screening. The study also highlights electronic record-based patient randomization as a way to determine relative effectiveness of support tools. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04118348.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Tamizaje Masivo , Humanos , Niño , Masculino , Femenino , Tamizaje Masivo/métodos , Lípidos/sangre , Registros Electrónicos de Salud
9.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33926993

RESUMEN

Many Americans fail to get life-saving vaccines each year, and the availability of a vaccine for COVID-19 makes the challenge of encouraging vaccination more urgent than ever. We present a large field experiment (N = 47,306) testing 19 nudges delivered to patients via text message and designed to boost adoption of the influenza vaccine. Our findings suggest that text messages sent prior to a primary care visit can boost vaccination rates by an average of 5%. Overall, interventions performed better when they were 1) framed as reminders to get flu shots that were already reserved for the patient and 2) congruent with the sort of communications patients expected to receive from their healthcare provider (i.e., not surprising, casual, or interactive). The best-performing intervention in our study reminded patients twice to get their flu shot at their upcoming doctor's appointment and indicated it was reserved for them. This successful script could be used as a template for campaigns to encourage the adoption of life-saving vaccines, including against COVID-19.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , Vacunas contra la Influenza , Gripe Humana/prevención & control , Visita a Consultorio Médico/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Médicos de Atención Primaria , Sistemas Recordatorios , Envío de Mensajes de Texto , Vacunación/psicología
10.
J Stroke Cerebrovasc Dis ; 33(1): 107477, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37966097

RESUMEN

OBJECTIVES: Previous studies suggest an association between central arterial stiffness (CAS) and intracranial atherosclerotic disease (ICAD) among Asian participants with stroke or hypertension; this association has not been evaluated in United States populations. We assessed the cross-sectional association of CAS with ICAD presence and burden in late-life, and differences in association by age, sex, and race. MATERIALS AND METHODS: We conducted a cross-sectional analysis of 1,285 Atherosclerosis Risk in Communities Study participants [mean age 75 (standard deviation: 5) years, 38 % male, 20  % Black] at Visit 5 (2011-2013). CAS was measured as carotid-femoral pulse wave velocity (cfPWV) using the Omron VP-1000 Plus. ICAD was assessed using high-resolution vessel wall MRI and MR angiography. We evaluated associations of a 1 standard deviation (SD) cfPWV (3.02 m/s) and high vs. non-high cfPWV (≥ 13.57 m/s vs. < 13.57 m/s) with presence of plaques (yes/no) and plaque number (0, 1-2, and >2) using multivariable logistic and ordinal logistic regression models adjusted for covariates. RESULTS: Each one SD greater cfPWV was associated with higher odds of plaque presence (odds ratio (OR)=1.32, 95 % confidence interval (CI): 1.22, 1.43), and an incrementally higher odds of number of plaques (OR 1-2 vs. 0 plaques = 1.21, 95 % CI: 1.10, 1.33; OR >2 vs. 0 plaques = 1.51, 95 % CI: 1.33,1.71). Results suggested differences by race, with greater magnitude associations among Black participants. CONCLUSIONS: CAS was positively associated with ICAD presence and burden; cfPWV may be a useful subclinical vascular measure for identification of individuals who are at high risk for cerebrovascular disease.


Asunto(s)
Aterosclerosis , Arteriosclerosis Intracraneal , Placa Aterosclerótica , Rigidez Vascular , Humanos , Masculino , Estados Unidos/epidemiología , Anciano , Femenino , Factores de Riesgo , Análisis de la Onda del Pulso/métodos , Estudios Transversales , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/epidemiología , Arteriosclerosis Intracraneal/complicaciones , Arteriosclerosis Intracraneal/diagnóstico por imagen , Arteriosclerosis Intracraneal/epidemiología
11.
J Infect Dis ; 228(Suppl 7): S648-S659, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37469133

RESUMEN

BACKGROUND: Ebolaviruses Ebola (EBOV), Sudan (SUDV), and Bundibugyo (BDBV) cause severe human disease, which may be accompanied by hemorrhagic syndrome, with high case fatality rates. Monovalent vaccines do not offer cross-protection against these viruses whose endemic areas overlap. Therefore, development of a panebolavirus vaccine is a priority. As a vaccine vector, human parainfluenza virus type 3 (HPIV3) has the advantages of needle-free administration and induction of both systemic and local mucosal antibody responses in the respiratory tract. METHODS: To minimize the antivector immunity, genes encoding the HPIV3 envelope proteins F and HN were removed from the vaccine constructs, resulting in expression of only the ebolavirus envelope protein-glycoprotein. These second-generation vaccine constructs were used to develop a combination vaccine against EBOV, SUDV, and BDBV. RESULTS: A single intranasal vaccination of guinea pigs or ferrets with the trivalent combination vaccine elicited humoral responses to each of the targeted ebolaviruses, including binding and neutralizing antibodies, as well as Fc-mediated effector functions. This vaccine protected animals from death and disease caused by lethal challenges with EBOV, SUDV, or BDBV. CONCLUSIONS: The combination vaccine elicited protection that was comparable to that induced by the monovalent vaccines, thus demonstrating the value of this combination trivalent vaccine.


Asunto(s)
Vacunas contra el Virus del Ébola , Ebolavirus , Fiebre Hemorrágica Ebola , Animales , Humanos , Cobayas , Anticuerpos Antivirales , Hurones , Anticuerpos Neutralizantes , Vacunas Combinadas
12.
J Pharmacol Exp Ther ; 385(1): 50-61, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36746611

RESUMEN

To provide back-up compounds to support the development of the GABAA receptor (GABAAR) potentiator KRM-II-81, three novel analogs were designed: replacing the pyridinyl with 2'-Cl-phenyl (FR-II-60), changing the positions of the N and O atoms in the oxazole ring with addition of an ethyl group (KPP-III-34 and KPP-III-51), or substituting a Br atom for the ethynyl of KRM-II-81 (KPP-III-34). The compounds bound to brain GABAARs. Intraperitoneal administration of FR-II-60 and KPP-III-34 produced anticonvulsant activity in mice [maximal electroshock (MES)-induced seizures or 6 Hz-induced seizures], whereas KPP-III-51 did not. Although all compounds were orally bioavailable, structural changes reduced the plasma and brain (FR-II-60 and KPP-III-51) exposures relative to KRM-II-81. Oral administration of each compound produced dose-dependent increases in the latency for both clonic and tonic seizures and the lethality induced by pentylenetetrazol (PTZ) in mice. Since KPP-III-34 produced the highest brain area under the curve (AUC) exposures, it was selected for further profiling. Oral administration of KPP-III-34 suppressed seizures in corneal-kindled mice, hippocampal paroxysmal discharges in mesial temporal lobe epileptic mice, and PTZ-induced convulsions in rats. Only transient sensorimotor impairment was observed in mice, and doses of KPP-III-34 up to 500 mg/kg did not produce impairment in rats. Molecular docking studies demonstrated that all compounds displayed a reduced propensity for binding to α1His102 compared with the sedating compound alprazolam; the bromine-substituted KPP-III-34 achieved the least interaction. Overall, these findings document the oral bioavailability and anticonvulsant efficacy of three novel analogs of KRM-II-81 with reduced sedative effects. SIGNIFICANCE STATEMENT: A new non-sedating compound, KRM-II-81, with reduced propensity for tolerance is moving into clinical development. Three new analogs were orally bioavailable, produced anticonvulsant effects in rodents, and displayed low sensorimotor impairment. KPP-III-34 demonstrated efficacy in models of pharmacoresistant epilepsy. Docking studies demonstrated a low propensity for compound binding to the α1His102 residue implicated in sedation. Thus, three additional structures have been added to the list of non-sedating imidazodiazepine anticonvulsants that could serve as backups in the clinical development of KRM-II-81.


Asunto(s)
Anticonvulsivantes , Epilepsia , Ratas , Ratones , Animales , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/química , Simulación del Acoplamiento Molecular , Convulsiones/tratamiento farmacológico , Convulsiones/inducido químicamente , Oxazoles/farmacología , Epilepsia/tratamiento farmacológico , Receptores de GABA-A/metabolismo , Pentilenotetrazol , Electrochoque
13.
Proc Natl Acad Sci U S A ; 117(32): 18948-18950, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32719133

RESUMEN

We resolve a controversy over two competing hypotheses about why people object to randomized experiments: 1) People unsurprisingly object to experiments only when they object to a policy or treatment the experiment contains, or 2) people can paradoxically object to experiments even when they approve of implementing either condition for everyone. Using multiple measures of preference and test criteria in five preregistered within-subjects studies with 1,955 participants, we find that people often disapprove of experiments involving randomization despite approving of the policies or treatments to be tested.


Asunto(s)
Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Investigación/normas , Ética en Investigación , Humanos , Distribución Aleatoria , Ensayos Clínicos Controlados Aleatorios como Asunto/ética
14.
Drug Dev Res ; 84(3): 527-531, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36748904

RESUMEN

A series of imidazodiazepines has been developed that possess reduced sedative liabilities but retain efficacy in anticonvulsant screening models. The latest of these compounds, (5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazole[1,5-α][1,4]diazepin-3-yl) oxazole known as KRM-II-81) is currently awaiting advancement into the clinic. A deuterated structural analog (D5-KRM-II-81) was made as a potential backup compound and studied here in comparison to KRM-II-81. In the present study, both compounds significantly prevented seizures in mice induced by 6 Hz (44 mA) electrical stimulation without significantly altering motoric function on a rotarod after intraperitoneal administration. Both compounds also significantly prevented clonic seizures, tonic seizures, and lethality induced by pentylenetetrazol in mice when given orally. D5-KRM-II-81 had a slightly longer duration of action against clonic and tonic seizures than KRM-II-81. Oral administration of 100 mg/kg of either KRM-II-81 or D5-KRM-II-81 was significantly less disruptive of sensorimotor function in mice than diazepam (5 mg/kg, p.o.). The present report documents that D5-KRM-II-81 represents another in this series of imidazodiazepines with anticonvulsant activity at doses that do not impair sensorimotor function.


Asunto(s)
Anticonvulsivantes , Diazepam , Ratones , Animales , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Diazepam/farmacología , Diazepam/uso terapéutico , Oxazoles , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico
17.
Proc Natl Acad Sci U S A ; 116(22): 10723-10728, 2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31072934

RESUMEN

Randomized experiments have enormous potential to improve human welfare in many domains, including healthcare, education, finance, and public policy. However, such "A/B tests" are often criticized on ethical grounds even as similar, untested interventions are implemented without objection. We find robust evidence across 16 studies of 5,873 participants from three diverse populations spanning nine domains-from healthcare to autonomous vehicle design to poverty reduction-that people frequently rate A/B tests designed to establish the comparative effectiveness of two policies or treatments as inappropriate even when universally implementing either A or B, untested, is seen as appropriate. This "A/B effect" is as strong among those with higher educational attainment and science literacy and among relevant professionals. It persists even when there is no reason to prefer A to B and even when recipients are treated unequally and randomly in all conditions (A, B, and A/B). Several remaining explanations for the effect-a belief that consent is required to impose a policy on half of a population but not on the entire population; an aversion to controlled but not to uncontrolled experiments; and a proxy form of the illusion of knowledge (according to which randomized evaluations are unnecessary because experts already do or should know "what works")-appear to contribute to the effect, but none dominates or fully accounts for it. We conclude that rigorously evaluating policies or treatments via pragmatic randomized trials may provoke greater objection than simply implementing those same policies or treatments untested.


Asunto(s)
Ética en Investigación , Ensayos Clínicos Pragmáticos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Ensayos Clínicos Pragmáticos como Asunto/ética , Ensayos Clínicos Pragmáticos como Asunto/legislación & jurisprudencia , Ensayos Clínicos Controlados Aleatorios como Asunto/ética , Ensayos Clínicos Controlados Aleatorios como Asunto/legislación & jurisprudencia , Resultado del Tratamiento
18.
Biopharm Drug Dispos ; 43(2): 66-75, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35194800

RESUMEN

The imidazodiazepine, (5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo [f]imidazole[1,5-α][1,4]diazepin-3-yl) oxazole or KRM-II-81) is a new α2/3-selective GABAkine (gamma aminobutyric acid A receptor potentiator) with anticonvulsant, anxiolytic, and antinociceptive activity in preclinical models. Reducing metabolism was utilized as a means of potentially extending the half-life of KRM-II-81. In vitro and in vivo studies were conducted to evaluate metabolic liabilities. Incubation of KRM-II-81 in hepatocytes revealed sites of potential metabolism on the oxazole and the diazepine rings. These sites were targeted in the design of a deuterated analog (D5-KRM-II-81) that could be evaluated as a potentially longer-acting analog. In contrast to computer predictions, peak plasma concentrations of D5-KRM-II-81 in rats were not significantly greater than those produced by KRM-II-81 after oral administration. Furthermore, brain disposition of KRM-II-81 was higher than that of D5-KRM-II-81. The half-life of the two compounds in either plasma or brain did not statistically differ from one another but the tmax for D5-KRM-II-81 occurred slightly earlier than for KRM-II-81. Non-metabolic considerations might be relevant to the lack of increases in exposure by D5-KRM-II-81. Alternative sites of metabolism on KRM-II-81, not targeted by the current deuteration process, are also possible. Despite its lack of augmented exposure, D5-KRM-II-81, like KRM-II-81, significantly prevented seizures induced by pentylenetetrazol when given orally. The present findings introduce a new orally active anticonvulsant GABAkine, D5-KRM-II-81.


Asunto(s)
Antibióticos Antituberculosos , Anticonvulsivantes , Animales , Anticonvulsivantes/farmacología , Oxazoles/metabolismo , Ratas , Receptores de GABA-A/metabolismo
19.
Drug Dev Res ; 83(4): 979-992, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35246861

RESUMEN

MIDD0301 is being developed as an oral drug to relax airway smooth muscle (ASM) and reduce lung inflammation in asthma. We report a comparative study of MIDD0301 and its S isomer (MIDD0301S), and found that the compounds have equivalent affinity for γ-aminobutyric acid type A receptor (GABAA R) expressed in rat brain, with half maximal inhibitory concentration values of 25.1 and 26.3 nM for the S and R enantiomers, respectively. Both compounds relaxed substance P contracted ASM within 30 min and neither enantiomer revealed affinity to 48 receptors in an off-target screen. Both enantiomers reduced airway hyperresponsiveness (AHR) with nebulized and oral dosing in two mouse models of bronchoconstriction. In A/J mice, which are very sensitive to methacholine-induced bronchoconstriction, we observed reduction of AHR at 10.8 mg/kg MIDD0301 and 15 mg/kg MIDD0301S. Using oral administration, 100 mg/kg/day for 3 days of either enantiomer was sufficient to reduce AHR. In a model of severe airway inflammation induced by interferon-γ and lipopolysaccharide (LPS), we observed reduction of AHR at 7.2 mg/kg for both enantiomers using nebulized administration, and at 100 mg/kg for oral administration. MIDD0301 and MIDD0301S did not undergo Phase I metabolism. Glucuronidation was observed for both compounds, whereas only MIDD0301 formed the corresponding glucoside in the presence of kidney microsomes. Pharmacokinetic analysis identified glucuronides as the major metabolite with concentrations up to 20-fold more than the parent compound. MIDD0301 glucuronide and MIDD0301 taurine bind GABAA Rs, although 10-fold weaker than MIDD0301. In mouse blood, the taurine adduct was only observed for MIDD0301. Overall, both compounds exhibited similar receptor binding and pharmacodynamic properties with subtle differences in metabolism and greater oral availability and blood concentrations of MIDD0301S.


Asunto(s)
Asma , Animales , Asma/tratamiento farmacológico , Asma/metabolismo , Azepinas , Imidazoles , Ratones , Ratas , Receptores de GABA , Taurina , Ácido gamma-Aminobutírico
20.
J Stroke Cerebrovasc Dis ; 31(5): 106388, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35193028

RESUMEN

OBJECTIVE: Elevated carotid intima-media thickness (cIMT) and carotid plaque are markers of arterial injury and may be linked to structural brain injury. We hypothesized cIMT or presence of carotid plaque at midlife are associated with presence of infarcts and cerebral microbleeds, greater white matter hyperintensity (WMH) volume, and smaller regional brain volumes in late-life. METHODS: We included 1,795 Atherosclerosis Risk in Communities (ARIC) Study participants (aged 57±6 years, 57% female, 23% Black) with carotid ultrasounds in 1990-1992 and brain MRI scans in 2011-2013. Weighted linear regression was used for brain volume outcomes, while logistic regression was used for infarcts and cerebral microbleeds. RESULTS: After multivariable adjustments, the highest cIMT quintile was associated with smaller deep gray matter (ß [95% CI]: -0.11 [-0.22, -0.01]) and cortical volume in a temporal-parietal meta region of interest (ROI) (ß [95% CI]: -0.10 [-0.20, -0.01]) in late-life. Similarly, those with carotid plaque had smaller regional brain volumes than those without (ßs [95% CIs]: -0.05 [-0.12, 0.03] and -0.06 [-0.13, 0.01] for deep gray matter and temporal-parietal meta ROI). No significant relations were observed with WMH volume, infarcts, or cerebral microbleeds. CONCLUSION: Over a median follow-up of 21 years, greater midlife cIMT and presence of carotid plaque were associated with smaller deep gray matter volume and cortical volume in a meta ROI involving temporal and parietal lobe regions typically involved in neurodegeneration, including Alzheimer's disease, in later life. Contrary to our hypothesis, associations between measures of arterial injury and markers of vascular brain injury were null.


Asunto(s)
Aterosclerosis , Enfermedades de las Arterias Carótidas , Placa Aterosclerótica , Aterosclerosis/complicaciones , Biomarcadores , Encéfalo/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Hemorragia Cerebral/complicaciones , Femenino , Humanos , Infarto/complicaciones , Imagen por Resonancia Magnética , Masculino , Placa Aterosclerótica/complicaciones , Factores de Riesgo
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