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The Mutant Mouse Resource and Research Center (MMRRC) Program is the pre-eminent public national mutant mouse repository and distribution archive in the USA, serving as a national resource of mutant mice available to the global scientific community for biomedical research. Established more than two decades ago with grants from the National Institutes of Health (NIH), the MMRRC Program supports a Consortium of regionally distributed and dedicated vivaria, laboratories, and offices (Centers) and an Informatics Coordination and Service Center (ICSC) at three academic teaching and research universities and one non-profit genetic research institution. The MMRRC Program accepts the submission of unique, scientifically rigorous, and experimentally valuable genetically altered and other mouse models donated by academic and commercial scientists and organizations for deposition, maintenance, preservation, and dissemination to scientists upon request. The four Centers maintain an archive of nearly 60,000 mutant alleles as live mice, frozen germplasm, and/or embryonic stem (ES) cells. Since its inception, the Centers have fulfilled 13,184 orders for mutant mouse models from 9591 scientists at 6626 institutions around the globe. Centers also provide numerous services that facilitate using mutant mouse models obtained from the MMRRC, including genetic assays, microbiome analysis, analytical phenotyping and pathology, cryorecovery, mouse husbandry, infectious disease surveillance and diagnosis, and disease modeling. The ICSC coordinates activities between the Centers, manages the website (mmrrc.org) and online catalog, and conducts communication, outreach, and education to the research community. Centers preserve, secure, and protect mutant mouse lines in perpetuity, promote rigor and reproducibility in scientific experiments using mice, provide experiential training and consultation in the responsible use of mice in research, and pursue cutting edge technologies to advance biomedical studies using mice to improve human health. Researchers benefit from an expansive list of well-defined mouse models of disease that meet the highest standards of rigor and reproducibility, while donating investigators benefit by having their mouse lines preserved, protected, and distributed in compliance with NIH policies.
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Investigación Biomédica , Modelos Animales de Enfermedad , Ratones , National Institutes of Health (U.S.) , Animales , Humanos , Ratones/genética , Reproducibilidad de los Resultados , Estados UnidosRESUMEN
PURPOSE: Diphthamide is a post-translationally modified histidine essential for messenger RNA translation and ribosomal protein synthesis. We present evidence for DPH5 as a novel cause of embryonic lethality and profound neurodevelopmental delays (NDDs). METHODS: Molecular testing was performed using exome or genome sequencing. A targeted Dph5 knockin mouse (C57BL/6Ncrl-Dph5em1Mbp/Mmucd) was created for a DPH5 p.His260Arg homozygous variant identified in 1 family. Adenosine diphosphate-ribosylation assays in DPH5-knockout human and yeast cells and in silico modeling were performed for the identified DPH5 potential pathogenic variants. RESULTS: DPH5 variants p.His260Arg (homozygous), p.Asn110Ser and p.Arg207Ter (heterozygous), and p.Asn174LysfsTer10 (homozygous) were identified in 3 unrelated families with distinct overlapping craniofacial features, profound NDDs, multisystem abnormalities, and miscarriages. Dph5 p.His260Arg homozygous knockin was embryonically lethal with only 1 subviable mouse exhibiting impaired growth, craniofacial dysmorphology, and multisystem dysfunction recapitulating the human phenotype. Adenosine diphosphate-ribosylation assays showed absent to decreased function in DPH5-knockout human and yeast cells. In silico modeling of the variants showed altered DPH5 structure and disruption of its interaction with eEF2. CONCLUSION: We provide strong clinical, biochemical, and functional evidence for DPH5 as a novel cause of embryonic lethality or profound NDDs with multisystem involvement and expand diphthamide-deficiency syndromes and ribosomopathies.
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Metiltransferasas , Trastornos del Neurodesarrollo , Adenosina Difosfato/metabolismo , Animales , Histidina/análogos & derivados , Histidina/metabolismo , Humanos , Metiltransferasas/genética , Ratones , Ratones Endogámicos C57BL , Trastornos del Neurodesarrollo/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , SíndromeRESUMEN
Heart failure (HF) following myocardial infarction (MI) is associated with high incidence of cardiac arrhythmias. Development of therapeutic strategy requires detailed understanding of electrophysiological remodeling. However, changes of ionic currents in ischemic HF remain incompletely understood, especially in translational large-animal models. Here, we systematically measure the major ionic currents in ventricular myocytes from the infarct border and remote zones in a porcine model of post-MI HF. We recorded eight ionic currents during the cell's action potential (AP) under physiologically relevant conditions using selfAP-clamp sequential dissection. Compared with healthy controls, HF-remote zone myocytes exhibited increased late Na+ current, Ca2+-activated K+ current, Ca2+-activated Cl- current, decreased rapid delayed rectifier K+ current, and altered Na+/Ca2+ exchange current profile. In HF-border zone myocytes, the above changes also occurred but with additional decrease of L-type Ca2+ current, decrease of inward rectifier K+ current, and Ca2+ release-dependent delayed after-depolarizations. Our data reveal that the changes in any individual current are relatively small, but the integrated impacts shift the balance between the inward and outward currents to shorten AP in the border zone but prolong AP in the remote zone. This differential remodeling in post-MI HF increases the inhomogeneity of AP repolarization, which may enhance the arrhythmogenic substrate. Our comprehensive findings provide a mechanistic framework for understanding why single-channel blockers may fail to suppress arrhythmias, and highlight the need to consider the rich tableau and integration of many ionic currents in designing therapeutic strategies for treating arrhythmias in HF.
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Potenciales de Acción/fisiología , Arritmias Cardíacas/fisiopatología , Calcio/metabolismo , Fenómenos Electrofisiológicos , Insuficiencia Cardíaca/fisiopatología , Infarto del Miocardio/fisiopatología , Miocitos Cardíacos/fisiología , Animales , Células Cultivadas , Miocitos Cardíacos/citología , PorcinosRESUMEN
BACKGROUND: Intravenous racemic ketamine is commonly administered for procedural sedation, although few pharmacokinetic studies have been conducted among children. Moreover, an optimal sampling schedule has not been derived to enable the conduct of pharmacokinetic studies that minimally inconvenience study participants. METHODS: Concentration-time data were obtained from 57 children who received 1-1.5 mg·kg(-1) of racemic ketamine as an intravenous bolus. A population pharmacokinetic analysis was conducted using nonlinear mixed effects models, and the results were used as inputs to develop a D-optimal sampling schedule. RESULTS: The pharmacokinetics of ketamine were described using a two-compartment model. The volume of distribution in the central and peripheral compartments were 20.5 lâ70 kg(-1) and 220 lâ70 kg(-1), respectively. The intercompartmental clearance and total body clearance were 87.3 and 87.9 l·h(-1) â70 kg(-1), respectively. Population parameter variability ranged from 34% to 98%. Initially, blood samples were drawn on 3-6 occasions spanning a range of 14-152 min after dosing. Using these data, we determined that four optimal sampling windows occur at 1-5, 5.5-7.5, 10-20, and 90-180 min after dosing. Monte Carlo simulations indicated that these sampling windows produced precise and unbiased ketamine pharmacokinetic parameter estimates. CONCLUSION: An optimal sampling schedule was developed that allowed assessment of the pharmacokinetic parameters of ketamine among children requiring short-term procedural sedation.
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Analgesia/métodos , Anestésicos Disociativos/sangre , Anestésicos Disociativos/farmacocinética , Ketamina/sangre , Ketamina/farmacocinética , Niño , Preescolar , Simulación por Computador , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Modelos Estadísticos , Método de Montecarlo , Factores de TiempoRESUMEN
While rodents are used extensively for studying pain, there is a lack of reported direct comparisons of thermal and mechanical pain testing methods in rats of different genetic backgrounds. Understanding the range of interindividual variability of withdrawal thresholds and thermal latencies based on these testing methods and/or genetic background is important for appropriate experimental design. Testing was performed in two common rat genetic backgrounds: outbred Sprague-Dawley (SD) and inbred Fischer 344 (F344). Male and female, 10- to 14-wk-old F344 and SD rats were used to assess withdrawal thresholds in 3 different modalities: the Randall-Selitto test (RST), Hargreaves test (HT), and tail flick test (TFT). The RST was performed by using an operator-controlled handheld instrument to generate a noxious pressure stimulus to the left hind paw. The HT and the TFT used an electronically controlled light source to deliver a noxious thermal stimulus to the left hind paw or tail tip, respectively. Rats of each sex and genetic background underwent one type of test on day 0 and day 7. Withdrawal thresholds and thermal latencies were compared among tests. No significant differences were observed. Our findings can serve as a guide for researchers considering these nociceptive tests for their experiments.
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Calor , Dimensión del Dolor , Umbral del Dolor , Ratas Endogámicas F344 , Ratas Sprague-Dawley , Animales , Femenino , Masculino , Ratas , Dimensión del Dolor/métodos , Dimensión del Dolor/veterinaria , Dolor/fisiopatologíaRESUMEN
Historically, xylazine has been utilized in veterinary medicine for decades as an anesthetic and analgesic sedative to facilitate safe handling, diagnostic testing, and surgical procedures in large animals. Currently, xylazine is an emerging threat to human health. It has been detected in the illicit drug supply chain, often as an adulterant. It has been more commonly added to illicit substances, most notably fentanyl, by drugmakers to enhance drug effect. End users are often unaware of its presence. This is alarming given the large number of xylazine-involved overdose deaths while laboratory detections are deficient and reversal agents are absent. Herein, we present the first documented case of xylazine identified via gas chromatography-tandem mass spectrometry at University of California Davis Health despite a peculiarly mild clinical presentation. We hope to increase awareness of this potentially fatal adulterant that is often missed in evaluation and engender further opportunities to study this ongoing issue.
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Fentanilo , Xilazina , Humanos , Masculino , Analgésicos Opioides/análisis , Contaminación de Medicamentos , Sobredosis de Droga/diagnóstico , Fentanilo/análogos & derivados , Fentanilo/análisis , Fentanilo/administración & dosificación , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas en Tándem/métodos , Xilazina/efectos adversos , AdultoRESUMEN
While rodents are used extensively for studying pain, there is a lack of reported direct comparisons of thermal and mechanical pain testing methods in rats of different genetic backgrounds. Understanding the range of interindividual variability of withdrawal thresholds and thermal latencies based on these testing methods and/or genetic background is important for appropriate experimental design. Testing was performed in two common rat genetic backgrounds: outbred Sprague-Dawley (SD) and inbred Fischer 344 (F344). Male and female, 10- to 14-wk-old F344 and SD rats were used to assess withdrawal thresholds in 3 different modalities: the Randall-Selitto test (RST), Hargreaves test (HT), and tail flick test (TFT). The RST was performed by using an operator-controlled handheld instrument to generate a noxious pressure stimulus to the left hind paw. The HT and the TFT used an electronically controlled light source to deliver a noxious thermal stimulus to the left hind paw or tail tip, respectively. Rats of each sex and genetic background underwent one type of test on day 0 and day 7. Withdrawal thresholds and thermal latencies were compared among tests. No significant differences were observed. Our findings can serve as a guide for researchers considering these nociceptive tests for their experiments.
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OBJECTIVE: To describe the pharmacodynamics and pharmacokinetics following an intravenous (IV) bolus dose of medetomidine in the horse. STUDY DESIGN: Prospective experimental trial. ANIMALS: Eight, mature healthy horses age 11.7 ± 4.6 (mean ± SD) years, weighing 557 ± 54 kg. METHODS: Medetomidine (10 µg kg(-1) ) was administered IV. Blood was sampled at fixed time points from before drug administration to 48 hours post administration. Behavioral, physiological and biochemical data were obtained at predetermined time points from 0 minutes to 24 hours post administration. An algometer was also used to measure threshold responses to noxious stimuli. Medetomidine concentrations were determined by liquid chromatography-Mass Spectrometry and used for calculation of pharmacokinetic parameters using noncompartmental and compartmental analysis. RESULTS: Pharmacokinetic analysis estimated that medetomidine peaked (8.86 ± 3.87 ng mL(-1) ) at 6.4 ± 2.7 minutes following administration and was last detected at 165 ± 77 minutes post administration. Medetomidine had a clearance of 39.6 ± 14.6 mL kg(-1) minute(-1) and a volume of distribution of 1854 ± 565 mL kg(-1). The elimination half-life was 29.1 ± 12.5 minutes. Glucose concentration reached a maximum of 176 ± 46 mg dL(-1) approximately 1 hour post administration. Decreased heart rate, respiratory rate, borborygmi, packed cell volume, and total protein concentration were observed following administration. Horses lowered their heads from 107 ± 12 to 20 ± 10 cm within 10 minutes of drug administration and gradually returned to normal. Horse mobility decreased after drug administration. An increased mechanical threshold was present from 10 to 45 minutes and horses were less responsive to sound. CONCLUSION AND CLINICAL RELEVANCE: Behavioral and physiological effects following intravenous administration positively correlate with pharmacokinetic profiles from plasma medetomidine concentrations. Glucose concentration gradually transiently increased following medetomidine administration. The analgesic effect of the drug appeared to have a very short duration.
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Analgesia/veterinaria , Analgésicos no Narcóticos/farmacocinética , Medetomidina/farmacocinética , Analgesia/métodos , Analgésicos no Narcóticos/sangre , Analgésicos no Narcóticos/farmacología , Animales , Glucemia/análisis , Bradicardia/inducido químicamente , Bradicardia/veterinaria , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Caballos/metabolismo , Inyecciones Intravenosas/veterinaria , Masculino , Medetomidina/sangre , Medetomidina/farmacología , Frecuencia Respiratoria/efectos de los fármacosRESUMEN
Management of critically ill patients requires simultaneous administration of many medications. Treatment for patient comorbidities may lead to drug-drug interactions which decrease drug efficacy or increase adverse reactions. Current practices rely on a one-size-fits-all dosing approach. Pharmacogenetic testing is generally reserved for addressing problems rather than used proactively to optimize care. We hypothesized that burn and surgery patients will have one or more genetic variants in drug metabolizing pathways used by one or more medications administered during the patient's hospitalization. The aim of this study was to determine the frequency of variants with abnormal function in the primary drug pathways and identify which medications may be impacted. Genetic (19 whole exome and 11 whole genome) and medication data from 30 pediatric burn and surgery patients were analyzed to identify pharmacogene-drug associations. Nineteen patients were identified with predicted altered function in one or more of the following genes: CYP2C9, CYP2C19, CYP2D6, and CYP3A4. The majority had decreased function, except for several patients with CYP2C19 rapid or ultrarapid variants. Some drugs administered during hospitalization that rely on these pathways include hydrocodone, oxycodone, methadone, ibuprofen, ketorolac, celecoxib, diazepam, famotidine, diphenhydramine, and glycopyrrolate. Approximately one-third of the patients tested had functionally impactful genotypes in each of the primary drug metabolizing pathways. This study suggests that genetic variants may in part explain the vast variability in drug efficacy and suggests that future pharmacogenetics research may optimize dosing regimens.
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Quemaduras , Pruebas de Farmacogenómica , Quemaduras/tratamiento farmacológico , Quemaduras/genética , Quemaduras/cirugía , Niño , Citocromo P-450 CYP2C19/genética , Genotipo , Humanos , Preparaciones Farmacéuticas , FarmacogenéticaRESUMEN
The sustained-release formulation of meloxicam (MSR) is a compounded NSAID that may provide pain relief for as long as 72 h after administration. MSR injection-site skin reactions have occurred in several species but have not previously been observed in mice. We investigated the development and progression of localized skin reactions after a single injection of MSR in Crl:CD1(ICR), C57BL/6J, and BALB/cJ mice. Each mouse received a subcutaneous injection of MSR (n = 60), standard-formulation meloxicam (MEL; n = 24) or saline (control; SC; n = 24) and was scored daily according to a 5-point system for erythema and mass characteristics. Mice were euthanized at either 7 or 14 d after injection and underwent postmortem analysis. MSR-treated mice had more erythematous and mass reactions than did MEL and SC mice. Mass lesions developed in 49 MSR mice (82%; 95% CI, 70% to 90%), 5 MEL animals (21%; 95% CI, 7% to 42%), and 1 SC mouse. MSR-treated BALB/cJ developed erythematous lesions less frequently than similarly treated Crl:CD1(ICR) or C57BL/6J. Lesions often were ventrolateral to the injection site. The median times to the appearance of mass and erythematous lesions were 2 d and 3 d, respectively. Histologically, the erythematous and mass reactions correlated with necrotizing to pyogranulomatous injection-site panniculitis. Inflammation severity scores at 7 and 14 d after injection were greater in the MSR-treated group than the other 2 groups. No strain- or sex-associated differences emerged except that inflammation severity scores at day 14 were higher in Crl:CD1(ICR) females than males. The character of the inflammatory response in MSR-treated mice did not differ between 7 and 14 d after injection, indicating that MSR-induced inflammation is slow to resolve. The ventral migration and delayed onset of MSR injection-site reactions could result in their being attributed to another cause or not being identified. Researchers and clinicians should be aware of the potential for slowly resolving injection-site reactions with MSR.
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Antiinflamatorios no Esteroideos/efectos adversos , Meloxicam/efectos adversos , Enfermedades de los Roedores/inducido químicamente , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Preparaciones de Acción Retardada , Femenino , Inyecciones Subcutáneas , Masculino , Meloxicam/administración & dosificación , Ratones , Ratones Endogámicos , Caracteres SexualesRESUMEN
BACKGROUND: Ceroid lipofuscinosis type 8 belongs to a heterogenous group of vision and life-threatening neurodegenerative diseases, neuronal ceroid lipofuscinosis (NCL). Effective therapy is limited to a single drug for treatment of ceroid lipofuscinosis type 2, necessitating animal disease models to facilitate further therapeutic development. Murine models are advantageous for therapeutic development due to easy genetic manipulation and rapid breeding, however appropriate genetic models need to be identified and characterized before being used for therapy testing. To date, murine models of ocular disease associated with ceroid lipofuscinosis type 8 have only been characterized in motor neuron degeneration mice. METHODS: Cln8-/- mice were produced by CRISPR/Cas9 genome editing through the International Mouse Phenotyping Consortium. Ophthalmic examination, optical coherence tomography, electroretinography, and ocular histology was performed on Cln8-/- mice and controls at 16 weeks of age. Quantification of all retinal layers, retinal pigmented epithelium, and the choriocapillaris was performed using images acquired with ocular coherence tomography and planimetry of histologic sections. Necropsy was performed to investigate concurrent systemic abnormalities. Clinical correlation with human patients with CLN8-associated retinopathy is provided. RESULTS: Retinal degeneration characterized by retinal pigment epithelium mottling, scattered drusen, and retinal vascular attenuation was noted in all Cln8-/- mice. Loss of inner and outer photoreceptor segment demarcation was noted on optical coherence tomography, with significant thinning of the whole retina (P=1e-9), outer nuclear layer (P=1e-9), and combined photoreceptor segments (P=1e-9). A global reduction in scotopic and photopic electroretinographic waveforms was noted in all Cln8-/- mice. Slight thickening of the inner plexiform layer (P=0.02) and inner nuclear layer (P=0.004), with significant thinning of the whole retina (P=0.03), outer nuclear layer (P=0.01), and outer photoreceptor segments (P=0.001) was appreciated on histologic sections. Scattered lipid vacuoles were noted in splenic red pulp of all Cln8-/- mice, though no gross systemic abnormalities were detected on necropsy. Retinal findings are consistent with those seen in patients with ceroid lipofuscinosis type 8. CONCLUSIONS: This study provides detailed clinical characterization of retinopathy in adult Cln8-/- mice. Findings suggest that Cln8-/- mice may provide a useful murine model for development of novel therapeutics needed for treating ocular disease in patients with ceroid lipofuscinosis type 8.
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Opioids are essential first line analgesics for pain management after burn injury. Opioid dosing remains challenging in burn patients, particularly in children, due to the immense variability in efficacy between patients. Opioid pharmacokinetics are altered in burned children, increasing variability and obviating dosing regimens extrapolated from adult-data. The present study aimed to characterize variability in fentanyl pharmacokinetics and identify significant contributors to variability in children with ≥10% total body surface area burn requiring fentanyl during routine wound care. We recorded patient demographics and clinical data. Blood samples were collected following fentanyl administration for pharmacokinetics at time 0, 30, 60, 120, and 240 minutes on day of admission and repeated on days 3 and 7. Serum fentanyl concentrations were quantified using tandem liquid chromatography mass spectrometry. Population analysis was used to estimate pharmacokinetics parameters. Fourteen patients, 1.2-17 years, with burns from 10-50.5% were included in analysis. A two-compartment model with body weight as a covariate best described fentanyl pharmacokinetics for the overall population. The population clearance and intercompartmental clearance were 7.19 and 2.16 L/hour, respectively, and the volume of distribution for the central and peripheral compartments was 4.01 and 25.1 L, respectively. Individual patient parameter estimates had extensive variability. This study confirmed the high variability in pediatric burn patient fentanyl pharmacokinetics and demonstrates similarities and differences to other populations reported in literature. Further research is needed with a larger number of patients to extensively investigate the impact of burns, genetic polymorphisms, and other factors on fentanyl efficacy and patient outcomes.
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Analgésicos Opioides/farmacocinética , Quemaduras/metabolismo , Fentanilo/farmacocinética , Adolescente , Factores de Edad , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/sangre , Tamaño Corporal , Quemaduras/complicaciones , Quemaduras/terapia , Niño , Preescolar , Femenino , Fentanilo/administración & dosificación , Fentanilo/sangre , Humanos , Tiempo de Internación , Masculino , Dolor/diagnóstico , Dolor/tratamiento farmacológico , Dolor/etiología , Estudios ProspectivosRESUMEN
The Roux-en-Y Gastric Bypass (RYGB) mouse model is a vital tool for studying the pathophysiology of bariatric surgery and contributes greatly to research on obesity and diabetes. However, complications including postsurgical hypoglycemia can have profoundly negative effects. Unlike in humans, blood glucose (BG) is not typically managed in postoperative rodents, despite their critical role as translational models; without this management, rodents can experience hypoglycemia, potentially impairing wound healing, decreasing survivability, complicating interpretation of research data, and limiting translational utility. In this project, we sought to identify an optimal method for minimally invasive administration of dextrose in C57BL/6N (n = 16; 8 male, 8 female) mice. To do so, we characterized BG pharmacokinetic profiles after subcutaneous and oral-transmucosal (OTM) administration of dextrose. Compared with OTM dosage, the subcutaneous route provided more consistent and reliable delivery of glucose and did not cause significant adverse reactions. We then evaluated the frequency of hypoglycemic events after RYGB in C57BL/6N mice (n = 16; 8 male, 8 female) and the effects of subcutaneous dextrose supplementation on morbidity and mortality. BG measurement and behavioral pain assessment (grimace test) were performed for 3 d after surgery. Hypoglycemic (BG ≤ 60 mg/dL) animals were assigned to dose (5% dextrose SC) or no-dose treatment groups. Nearly all (87%) mice became hypoglycemic; 2 of these mice died. No significant intergroup difference in grimace score or mortality was detected. Overall, our results demonstrate that hypoglycemia is a frequent adverse event after RYGB in mice and that subcutaneous injection of dextrose is a safe and effective way to manage hypoglycemia. Further studies are necessary to optimize the intervention threshold and optimal dosage; regardless, we recommend glycemic management after RYGB surgery in mice.
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Derivación Gástrica/efectos adversos , Glucosa/administración & dosificación , Hipoglucemia/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Femenino , Derivación Gástrica/mortalidad , Glucosa/farmacocinética , Hipoglucemia/etiología , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
An extended-release formulation of the NSAID meloxicam (MSR) is used to provide 72 h of continuous analgesia in many species, including rodents. Although standard formulations of meloxicam are frequently used in rats with no observable injection-site reactions, the potential adverse effects from MSR have not been characterized sufficiently nor has a prospective study of these effects been performed in rats. To address this deficiency, we evaluated injection-site reactions after a single subcutaneous administration of MSR (n = 16) or sterile saline (SC, n = 6) in the flank of age- and sex-matched Sprague-Dawley rats. Mass and erythema scores were measured daily for 2 wk, and injection sites were collected for histopathology after euthanasia. Rats were randomly selected for euthanasia at 7 d (n = 12) or 14 d (n = 10) after injection to capture the subacute and chronic phases of mass and erythematic lesion formation. No rats in the SC group developed lesions, whereas all 16 MSR-treated rats developed masses. The median time to first mass in the MSR treatment group was 3 d (95% CI, 2-3 d), and nearly 8 d for erythema (95% CI, 6.7-9.1 d). The trajectory of mass lesion severity showed rapid progression from score 1 at onset (day 2 or 3) to score 2 for almost all animals by day 5 or 6. Histopathology was characterized by localized inflammation with central necrosis and peripheral fibrosis, with some sections showing developing draining tracts. Given the high prevalence and severity of localized skin reactions, MSR analgesia should be considered carefully for Sprague-Dawley rats.
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Analgesia/veterinaria , Antiinflamatorios no Esteroideos/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Meloxicam/efectos adversos , Ratas Sprague-Dawley , Analgesia/métodos , Animales , Femenino , Masculino , Dolor/tratamiento farmacológico , Estudios Prospectivos , RatasRESUMEN
BACKGROUND: Desminopathy is a clinically heterogeneous muscle disease caused by over 60 different mutations in desmin. The most common mutation with a clinical phenotype in humans is an exchange of arginine to proline at position 350 of desmin leading to p.R350P. We created the first CRISPR-Cas9 engineered rat model for a muscle disease by mirroring the R350P mutation in humans. METHODS: Using CRISPR-Cas9 technology, Des c.1045-1046 (AGG > CCG) was introduced into exon 6 of the rat genome causing p.R349P. The genotype of each animal was confirmed via quantitative PCR. Six male rats with a mutation in desmin (n = 6) between the age of 120-150 days and an equal number of wild type littermates (n = 6) were used for experiments. Maximal plantar flexion force was measured in vivo and combined with the collection of muscle weights, immunoblotting, and histological analysis. In addition to the baseline phenotyping, we performed a synergist ablation study in the same animals. RESULTS: We found a difference in the number of central nuclei between desmin mutants (1 ± 0.4%) and wild type littermates (0.2 ± 0.1%; P < 0.05). While muscle weights did not differ, we found the levels of many structural proteins to be altered in mutant animals. Dystrophin and syntrophin were increased 54% and 45% in desmin mutants, respectively (P < 0.05). Dysferlin and Annexin A2, proteins associated with membrane repair, were increased two-fold and 32%, respectively, in mutants (P < 0.05). Synergist ablation caused similar increases in muscle weight between mutant and wild type animals, but changes in fibre diameter revealed that fibre hypertrophy in desmin mutants was hampered compared with wild type animals (P < 0.05). CONCLUSIONS: We created a novel animal model for desminopathy that will be a useful tool in furthering our understanding of the disease. While mutant animals at an age corresponding to a preclinical age in humans show no macroscopic differences, microscopic and molecular changes are already present. Future studies should aim to further decipher those biological changes that precede the clinical progression of disease and test therapeutic approaches to delay disease progression.
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Sistemas CRISPR-Cas , Enfermedades Musculares , Animales , Desmina/genética , Desmina/metabolismo , Distrofina , Masculino , Ratones , Enfermedades Musculares/genética , Mutación , RatasRESUMEN
Pain management is critical for burn care. Unfortunately, interindividual variation in pharmacokinetics (PK) due to burn hypermetabolism and genetic polymorphisms can lead to treatment failures in this at-risk population. Analgesics may be affected by genetic polymorphisms affecting cytochrome P450 (CYP) drug metabolizing enzymes. Fentanyl is a common opiate primarily metabolized by CYP3A4 subtypes. Recent studies demonstrate CYP2D6 variants, affecting fentanyl PK. Functional CYP polymorphisms can significantly alter opiate levels resulting in inadequate analgesia or life-threatening toxicity. The goal of our study was to evaluate fentanyl PK and assess associations with CYP polymorphisms. We obtained samples from the previously banked blood of 13 patients (eight males and five females) with >20% TBSA burns. Mean (SD) patient age was 41.7 (14.5) years, and mean burn size was 25.8 (15.3) %TBSA. Plasma fentanyl was quantified, and CYP genotyping was performed. Pharmacokinetic analysis was performed using Monolix software (Lixsoft, France) with a two-compartment population model best-representing fentanyl profiles. Three CYP slow-metabolizing genotypes were identified, which included CYP2D6*9, CYP2D6*29, and CYP3A4*1B. All three patients with variant polymorphisms had increased serum fentanyl concentrations due to impaired clearance. This pilot study supports the need for further research in this topic, and CYP genotyping of individual patients prior to receiving opiate analgesics to inform precision-guided decisions, improve therapeutic efficacy, and, most importantly, increase patient well-being and safety.
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Analgésicos Opioides/farmacocinética , Quemaduras/tratamiento farmacológico , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Fentanilo/farmacocinética , Polimorfismo Genético , Adulto , Femenino , Genotipo , Humanos , Masculino , Proyectos PilotoRESUMEN
Studies indicate that the gut microbiota (GM) can significantly influence both local and systemic host physiologic processes. With rising concern for optimization of experimental reproducibility and translatability, it is essential to consider the GM in study design. However, GM profiles can vary between rodent producers making consistency between models challenging. To circumvent this, we developed outbred CD1 mouse colonies with stable, complex GM profiles that can be used as donors for a variety of GM transfer techniques including rederivation, co-housing, cross-foster, and fecal microbiota transfer (FMT). CD1 embryos were surgically transferred into CD1 or C57BL/6 surrogate dams that varied by GM composition and complexity to establish four separate mouse colonies harboring GM profiles representative of contemporary mouse producers. Using targeted 16S rRNA amplicon sequencing, subsequent female offspring were found to have similar GM profiles to surrogate dams. Furthermore, breeding colonies of CD1 mice with distinct GM profiles were maintained for nine generations, demonstrating GM stability within these colonies. To confirm GM stability, we shipped cohorts of these four colonies to collaborating institutions and found no significant variation in GM composition. These mice are an invaluable experimental resource that can be used to investigate GM effects on mouse model phenotype.
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Cruzamiento/métodos , Trasplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal , Animales , Transferencia de Embrión/métodos , Femenino , Vivienda para Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos AnimalesRESUMEN
OBJECTIVE: To determine if binge ethanol consumption before ovulation affects oocyte quality, gene expression, and subsequent embryo development. DESIGN: Binge levels of ethanol were given twice weekly for 6 months, followed by a standard in vitro fertilization cycle and subsequent natural mating. SETTING: National primate research center. ANIMAL(S): Adult female rhesus monkeys. INTERVENTION(S): Binge levels of ethanol, given twice weekly for 6 months before a standard in vitro fertilization cycle with or without embryo culture. With in vivo development, ethanol treatment continued until pregnancy was identified. MAIN OUTCOME MEASURE(S): Oocyte and cumulus/granulosa cell gene expression, embryo development to blastocyst, and pregnancy rate. RESULT(S): Embryo development in vitro was reduced; changes were found in oocyte and cumulus cell gene expression; and spontaneous abortion during very early gestation increased. CONCLUSION(S): This study provides evidence that binge drinking can affect the developmental potential of oocytes even after alcohol consumption has ceased.
Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/complicaciones , Consumo Excesivo de Bebidas Alcohólicas/patología , Etanol/toxicidad , Estado de Salud , Modelos Animales , Animales , Efecto de Cohortes , Etanol/administración & dosificación , Femenino , Humanos , Macaca mulatta , Oocitos/efectos de los fármacos , Oocitos/patología , Embarazo , Índice de Embarazo/tendenciasRESUMEN
Severe burn injury results in a multifaceted physiological response that significantly alters drug pharmacokinetics and pharmacodynamics (PK/PD). This response includes hypovolemia, increased vascular permeability, increased interstitial hydrostatic pressure, vasodilation, and hypermetabolism. These physiologic alterations impact drug distribution and excretion-thus varying the drug therapeutic effect on the body or microorganism. To this end, in order to optimize critical care for the burn population it is essential to understand how burn injury alters PK/PD parameters. The purpose of this article is to describe the relationship between burn injury and drug PK/PD. We conducted a literature review via PubMed and Google to identify burn-related PK/PD studies. Search parameters included "pharmacokinetics," "pharmacodynamics," and "burns." Based on our search parameters, we located 38 articles that studied PK/PD parameters specifically in burns. Twenty-seven articles investigated PK/PD of antibiotics, 10 assessed analgesics and sedatives, and one article researched an antacid. Out of the 37 articles, there were 19 different software programs used and eight different control groups. The mechanisms behind alterations in PK/PD in burns remain poorly understood. Dosing techniques must be adapted based on burn injury-related changes in PK/PD parameters in order to ensure drug efficacy. Although several PK/PD studies have been undertaken in the burn population, there is wide variation in the analytical techniques, software, and study sample sizes used. In order to refine dosing techniques in burns and consequently improve patient outcomes, there must be harmonization among PK/PD analyses.