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1.
Trauma Case Rep ; 51: 101007, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38590923

RESUMEN

An 18-year-old female presented to the emergency department after a motor vehicle collision. Initial imaging revealed a liver laceration. Subsequent labs showed significantly elevated prothrombin time, international normalized ratio, and activated partial thromboplastin time. Thromboelastography demonstrated a flatline tracing. The patient denied use of anticoagulation but admitted to synthetic cannabinoid use. It was believed the patient had taken synthetic cannabinoid contaminated by brodifacoum. She was therefore given prothrombin complex concentrate and vitamin K with blood products. The patient underwent sequential embolization, laparotomy, thoracotomy, and repair of the vena cava with a shunt. Thirty minutes postoperatively, her coagulation tests and thromboelastography were much improved. Two and a half hours postoperatively, it was determined she had sustained non-survivable injuries. The patient experienced brain death due to prolonged hypotension as a result of hemorrhagic shock with bleeding exacerbated by brodifacoum. To our knowledge, this is the first case reported of a trauma-induced coagulopathy exacerbated by brodifacoum-contaminated synthetic cannabinoid. Her coagulopathy was clearly not due to trauma alone and contributed greatly to the difficulty in controlling hemorrhage. The synthetic cannabinoid-associated coagulopathy rendered her otherwise potentially survivable injuries fatal. Given the frequency of multiple trauma and the recent increase in the prevalence of synthetic cannabinoid, it can be expected that the incidence of trauma complicated by synthetic cannabinoid-associated coagulopathy will increase in the near future. For patients that present with prolonged prothrombin time and/or activated partial thromboplastin time, it is important to inquire about recent synthetic cannabinoid use.

2.
J Equine Vet Sci ; 130: 104925, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37717678

RESUMEN

The use of dexamethasone to control equine asthma is a common and effective treatment. Although short-term systemic dexamethasone treatment has not been shown to induce systemic immunosuppression in the horse, the goal of this study was to determine whether inhaled ciclesonide, an FDA-approved drug for the treatment of equine asthma, exerts any systemic immunosuppressive effects when compared to dexamethasone-treated and untreated horses. Eighteen light, mixed breed horses, ranging in age from 3 to 8 years of age, were used for this study and randomly assigned to one of three treatment groups: (1) nontreated controls, (2) ciclesonide treatment, or (3) dexamethasone treatment. Blood was collected daily for steady-state messenger RNA (mRNA) analysis, as well as at Days 0, 5, 10, and 15 of treatment for in vitro stimulation with Concanavalin A (ConA). Messenger RNA relative quantities were determined using RT-qPCR for select genes. Two-way, repeated measures analysis of variance was used to analyze qPCR data and results considered significant at P < .05. There were significant decreases in the steady-state, whole-blood expression of granzyme B and interferon-γ due to dexamethasone treatment, when compared to the nontreated control group. Within ConA-stimulated samples, there remained a suppressive effect of dexamethasone treatment on granzyme B expression compared to nontreated control horses. Similar effects were not noted in the ciclesonide-treated horses. Significant effects of ciclesonide treatment on markers of immune function were not noted in this study, suggesting a low risk for immunosuppression with inhaled ciclesonide treatment.

3.
Mol Biol Evol ; 40(9)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37619989

RESUMEN

The most highly expressed genes in microbial genomes tend to use a limited set of synonymous codons, often referred to as "preferred codons." The existence of preferred codons is commonly attributed to selection pressures on various aspects of protein translation including accuracy and/or speed. However, gene expression is condition-dependent and even within single-celled organisms transcript and protein abundances can vary depending on a variety of environmental and other factors. Here, we show that growth rate-dependent expression variation is an important constraint that significantly influences the evolution of gene sequences. Using large-scale transcriptomic and proteomic data sets in Escherichia coli and Saccharomyces cerevisiae, we confirm that codon usage biases are strongly associated with gene expression but highlight that this relationship is most pronounced when gene expression measurements are taken during rapid growth conditions. Specifically, genes whose relative expression increases during periods of rapid growth have stronger codon usage biases than comparably expressed genes whose expression decreases during rapid growth conditions. These findings highlight that gene expression measured in any particular condition tells only part of the story regarding the forces shaping the evolution of microbial gene sequences. More generally, our results imply that microbial physiology during rapid growth is critical for explaining long-term translational constraints.


Asunto(s)
Uso de Codones , Magnoliopsida , Proteómica , Escherichia coli/genética , Biosíntesis de Proteínas , Saccharomyces cerevisiae/genética , Sesgo
4.
J Equine Vet Sci ; 128: 104892, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37433342

RESUMEN

Accumulating high-speed exercise has been identified as a significant risk factor for catastrophic injuries in racing Thoroughbreds. Injuries, regardless of severity, are a main cause of withdrawal from the racing industry, raising animal welfare concerns and resulting in significant economic losses. While most of the current literature focuses on injuries incurred during racing rather than training, the present study aims to help fill this gap. As such, peripheral blood was collected weekly, prior to exercise or administration of medication, from eighteen, two-year-old Thoroughbreds throughout their first season of race training. Messenger RNA (mRNA) was isolated and used to analyze the expression of 34 genes via RT-qPCR. Statistical analysis of the noninjured horses (n = 6) showed that 13 genes were significantly correlated with increasing average weekly high-speed furlong performance. Additionally, there was a negative correlation for CXCL1, IGFBP3, and MPO with both cumulative high-speed furlongs and week of training for all horses. Comparison of both groups showed opposing correlations between the anti-inflammatory index (IL1RN, IL-10, and PTGS1) and average weekly high-speed furlong performance. Furthermore, evaluation of training effects on mRNA expression during the weeks surrounding injury, showed differences between groups in IL-13 and MMP9 at -3 and -2 weeks prior to injury. While some previously reported relationships between exercise adaptation and mRNA expression were not noted in this study, this may have been due to the small sample size. Several novel correlations, however, were identified and warrant further investigation as markers of exercise adaptation or potential risk for injury.


Asunto(s)
Estudios de Casos y Controles , Caballos , Animales
5.
Clin Breast Cancer ; 23(7): 721-728, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37474374

RESUMEN

BACKGROUND: To evaluate the efficacy of crofelemer, a first in class anti-secretory anti-diarrheal agent, to manage neratinib-induced diarrhea in patients with early-stage breast cancer taking adjuvant neratinib. PATIENTS AND METHODS: This single center, open label trial enrolled patients with Stage 2 to 3 HER2+ breast cancer taking adjuvant neratinib. One cohort took prophylactic crofelemer 125 mg bid and loperamide in the first 2 cycles, and as needed in subsequent cycles. The second cohort took dose-escalated neratinib with loperamide as needed (DE cohort). The primary endpoint was incidence of grade ≥ 3 diarrhea in the first 2 cycles. RESULTS: Seven patients in the crofelemer cohort and 4 in the DE cohort were enrolled. In the first 2 cycles, 2 patients (29%) in the crofelemer cohort and 2 patients (50%) in the DE cohort experienced grade 3 diarrhea lasting 1 day on average. After cycle 2, no additional patients in either cohort had grade 3 diarrhea. Five of 7 patients controlled diarrhea with crofelemer alone. There were no grade 4 diarrhea events in either cohort. Three patients in the crofelemer cohort dose-reduced neratinib due to diarrhea in the first 2 cycles. Patients in the crofelemer cohort had an average of 0.58 diarrhea episodes/day. 82% experienced constipation, all grade 1. CONCLUSIONS: This is the first study to investigate crofelemer for neratinib-induced diarrhea and demonstrates crofelemer activity in this setting. Further investigation of crofelemer for diarrhea secondary to cancer treatment is needed.


Asunto(s)
Neoplasias de la Mama , Quinolinas , Femenino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama/tratamiento farmacológico , Diarrea/inducido químicamente , Diarrea/epidemiología , Loperamida/efectos adversos , Quinolinas/efectos adversos , Receptor ErbB-2/uso terapéutico
6.
bioRxiv ; 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-36993177

RESUMEN

The most highly expressed genes in microbial genomes tend to use a limited set of synonymous codons, often referred to as "preferred codons." The existence of preferred codons is commonly attributed to selection pressures on various aspects of protein translation including accuracy and/or speed. However, gene expression is condition-dependent and even within single-celled organisms transcript and protein abundances can vary depending on a variety of environmental and other factors. Here, we show that growth rate-dependent expression variation is an important constraint that significantly influences the evolution of gene sequences. Using large-scale transcriptomic and proteomic data sets in Escherichia coli and Saccharomyces cerevisiae, we confirm that codon usage biases are strongly associated with gene expression but highlight that this relationship is most pronounced when gene expression measurements are taken during rapid growth conditions. Specifically, genes whose relative expression increases during periods of rapid growth have stronger codon usage biases than comparably expressed genes whose expression decreases during rapid growth conditions. These findings highlight that gene expression measured in any particular condition tells only part of the story regarding the forces shaping the evolution of microbial gene sequences. More generally, our results imply that microbial physiology during rapid growth is critical for explaining long-term translational constraints.

7.
Equine Vet J ; 55(5): 905-915, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36397207

RESUMEN

BACKGROUND: Intra-articular (IA) corticosteroids are regularly used in equine athletes for the control of joint inflammation. OBJECTIVES: The goal of this study was to use an acute synovitis inflammation model to determine the residual effects of IA betamethasone and triamcinolone acetonide on various inflammatory parameters and lameness. STUDY DESIGN: Crossover randomised trial. METHODS: Five mixed-breed, 2-year-old horses were randomly allocated to an IA treatment of the radiocarpal joint with 9 mg of either betamethasone or triamcinolone acetonide. Two weeks following treatment, horses were injected with 1 µg of lipopolysaccharide (LPS) diluted in 1 ml of saline. Following LPS injection, horses were crossed-over and both sets of injections were repeated after a washout period. Blood samples were collected at multiple time points for mRNA analysis, as well as serum amyloid A (SAA) and cortisol determination. At each time point, lameness was also subjectively scored. Additional injections with saline-only or LPS-only (twice) were conducted as negative and positive controls, respectively. Two-way repeated measures analysis of variance was used to analyse all data. RESULTS: Corticosteroid-only treatments result in significant mRNA expression differences, as well as significant and prolonged cortisol suppression. Following LPS injection, there was a residual treatment effect with triamcinolone evidenced by a significant treatment effect on IL-6 and PTGS1 (cyclooxygenase-1), lameness, SAA and cortisol concentrations, while only IL-6 expression was affected by betamethasone. MAIN LIMITATIONS: The acute synovitis model used here results in significant inflammation and is not representative of the low-grade inflammation seen with typical joint disease and residual anti-inflammatory effects may be more profound in naturally occurring joint disease. CONCLUSIONS: Current regulatory guidelines may be insufficient if the concern is residual anti-inflammatory effects. Additionally, intra-articular corticosteroid administration is not without risk, as evidenced by a significant suppression of serum cortisol concentration and, as such, the benefits of their administration should be weighed against those risks.


Asunto(s)
Enfermedades de los Caballos , Artropatías , Sinovitis , Caballos , Animales , Triamcinolona Acetonida/uso terapéutico , Betametasona/uso terapéutico , Hidrocortisona , Lipopolisacáridos , Cojera Animal/tratamiento farmacológico , Interleucina-6 , Sinovitis/inducido químicamente , Sinovitis/tratamiento farmacológico , Sinovitis/veterinaria , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/veterinaria , Artropatías/veterinaria , Antiinflamatorios , Inyecciones Intraarticulares/veterinaria , Enfermedades de los Caballos/tratamiento farmacológico , Enfermedades de los Caballos/metabolismo
8.
J Equine Vet Sci ; 110: 103771, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34973594

RESUMEN

Loss of skeletal muscle mass likely compromises performance and welfare in horses and thus routine monitoring would be valuable. Currently available methods to assess muscle mass require expert knowledge and are often expensive. To provide a simple method, a muscle atrophy scoring system (MASS) was created and tested by three evaluators (raters) in 38 horses of varying age, breed, and health status. Inter-rater agreement on atrophy scores was in the good-to-excellent range for ratings of the neck (ICC = 0.62), back (ICC = 0.62) and hind (ICC = 0.76) regions but was poor for the abdominal region (ICC = 0.29). Due to this low agreement, the abdominal region was excluded from further analysis. Associations between muscle atrophy scores and age, pituitary pars intermedia dysfunction (PPID) status, and body composition indicators, including weight and estimated fat-free mass (FFM), were examined. Weight was inversely associated with neck, back and hind muscle atrophy scores (ß = -0.008, ß = -0.008, ß = -0.009, respectively; all P <0.001), but estimated FFM was not associated with muscle atrophy scores at any region (P >0.05). Age was positively related to neck (ß = 0.030, P <0.01), back (ß = 0.037, P <0.001) and hind (ß = 0.040, P <0.001) muscle atrophy scores. PPID-positive horses (n = 4) had higher muscle atrophy scores than PPID-negative horses (n = 23), even after adjusting for age (P <0.05). This data suggests that neck, back and hind region evaluations by individual raters likely have acceptable reliability. In addition, these findings support further evaluation of the potential benefits of the MASS to identify and monitor muscle atrophy in horses.


Asunto(s)
Enfermedades de los Caballos , Atrofia Muscular , Adenohipófisis Porción Intermedia , Envejecimiento , Animales , Enfermedades de los Caballos/diagnóstico , Caballos , Atrofia Muscular/diagnóstico , Atrofia Muscular/veterinaria , Adenohipófisis Porción Intermedia/patología , Reproducibilidad de los Resultados
9.
Commun Biol ; 4(1): 1352, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34857859

RESUMEN

Protein-protein interaction (PPI) networks represent complex intra-cellular protein interactions, and the presence or absence of such interactions can lead to biological changes in an organism. Recent network-based approaches have shown that a phenotype's PPI network's resilience to environmental perturbations is related to its placement in the tree of life; though we still do not know how or why certain intra-cellular factors can bring about this resilience. Here, we explore the influence of gene expression and network properties on PPI networks' resilience. We use publicly available data of PPIs for E. coli, S. cerevisiae, and H. sapiens, where we compute changes in network resilience as new nodes (proteins) are added to the networks under three node addition mechanisms-random, degree-based, and gene-expression-based attachments. By calculating the resilience of the resulting networks, we estimate the effectiveness of these node addition mechanisms. We demonstrate that adding nodes with gene-expression-based preferential attachment (as opposed to random or degree-based) preserves and can increase the original resilience of PPI network in all three species, regardless of gene expression distribution or network structure. These findings introduce a general notion of prospective resilience, which highlights the key role of network structures in understanding the evolvability of phenotypic traits.


Asunto(s)
Escherichia coli/fisiología , Expresión Génica , Redes Reguladoras de Genes , Mapas de Interacción de Proteínas , Saccharomyces cerevisiae/fisiología , Biología Computacional , Escherichia coli/genética , Humanos , Saccharomyces cerevisiae/genética
10.
J Mol Evol ; 88(10): 731-741, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33230664

RESUMEN

In many applications of evolutionary inference, a model of protein evolution needs to be fitted to the amino acid variation at individual sites in a multiple sequence alignment. Most existing models fall into one of two extremes: Either they provide a coarse-grained description that lacks biophysical realism (e.g., dN/dS models), or they require a large number of parameters to be fitted (e.g., mutation-selection models). Here, we ask whether a middle ground is possible: Can we obtain a realistic description of site-specific amino acid frequencies while severely restricting the number of free parameters in the model? We show that a distribution with a single free parameter can accurately capture the variation in amino acid frequency at most sites in an alignment, as long as we are willing to restrict our analysis to predicting amino acid frequencies by rank rather than by amino acid identity. This result holds equally well both in alignments of empirical protein sequences and of sequences evolved under a biophysically realistic all-atom force field. Our analysis reveals a near universal shape of the frequency distributions of amino acids. This insight has the potential to lead to new models of evolution that have both increased realism and a limited number of free parameters.


Asunto(s)
Aminoácidos , Evolución Molecular , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Aminoácidos/genética , Modelos Genéticos , Alineación de Secuencia
11.
Biochem Biophys Res Commun ; 519(3): 633-638, 2019 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-31540695

RESUMEN

AMP-activated protein kinase (AMPK) is a member of Ser/Thr kinases that has been shown to regulate energy balance. Although recent studies have demonstrated the function of AMPK in adipose tissue using different fat-specific AMPK knockout mouse models, the results were somewhat inconsistent. For this study, we tested the hypothesis that AMPK in adipose tissue regulates whole body glucose metabolism. To determine the role of adipose tissue AMPK in vivo, we generated fat-specific AMPKα1/α2 knockout mice (AMPKFKO) using the Cre-loxP system. Body weights of AMPKFKO mice were not different between 8 and 27 weeks of age. Furthermore, tissue weights (liver, kidney, muscle, heart and white and brown adipose tissue) were similar to wild type littermates and DEXA scan analysis revealed no differences in percentages of body fat and lean mass. Knockout of AMPKα1/α2 in adipose tissue abolished basal and AICAR-stimulated phosphorylation of AMPK and Acetyl-CoA Carboxylase, a downstream of AMPK. Despite of the ablation of AICAR-stimulated AMPK phosphorylation, the blood glucose-lowering effect of AICAR injection (i.p.) was normal in AMPKFKO mice. In addition, AMPKFKO displayed normal fasting blood glucose concentration, glucose tolerance, insulin tolerance, and insulin signaling, indicating normal whole body glucose metabolism. These data demonstrate that adipose tissue AMPK plays a minimum role in whole body glucose metabolism on a chow diet.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Tejido Adiposo/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Glucosa/metabolismo , Ribonucleótidos/metabolismo , Proteínas Quinasas Activadas por AMP/deficiencia , Aminoimidazol Carboxamida/administración & dosificación , Aminoimidazol Carboxamida/metabolismo , Animales , Dieta , Inyecciones Intraperitoneales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Ribonucleótidos/administración & dosificación
12.
Sci Rep ; 9(1): 4834, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30886198

RESUMEN

The complexity of immune responses limits the usefulness of univariate methods in answering complex immunology questions. To demonstrate the utility of a multivariate approach, we employ such approach to compare T cells of African green monkeys (AGMs) and rhesus macaques (RMs). Among the most prominent distinguishing features we found were lower CD3 and higher CD28 surface expression in AGMs compared to RMs. After in vitro stimulation, a larger proportion of AGM T cells secreted cytokines, especially those producing more than one cytokine (i.e. multifunctional cells). To find out whether multifunctional responses associate with protection in other species, we compared T cells of cynomolgus macaques (CMs) infected with wild-type Simian Immunodeficiency Virus (SIV) to those of CMs infected (vaccinated) with a replication-defective virus. Wild-type SIV infection in macaques leads to simian Acquired Immunodeficiency Syndrome (AIDS), which does not happen in animals previously vaccinated with a replication-defective virus. Interestingly, after in vitro stimulation, multifunctional cells were more abundant among T cells of vaccinated CMs. Our results propose T-cell multifunctionality as a potentially useful marker of immunity, although additional verification is needed. Finally, we hope our multivariate model and its associated validation methods will inform future studies in the field of immunology.


Asunto(s)
Técnicas Inmunológicas/métodos , Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Antígenos CD28/metabolismo , Complejo CD3/metabolismo , Chlorocebus aethiops/inmunología , Chlorocebus aethiops/virología , Citocinas/inmunología , Citocinas/metabolismo , Inmunogenicidad Vacunal , Recuento de Linfocitos , Macaca mulatta/inmunología , Macaca mulatta/virología , Vacunas contra el SIDAS/administración & dosificación , Síndrome de Inmunodeficiencia Adquirida del Simio/sangre , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Especificidad de la Especie , Subgrupos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Replicación Viral/genética , Replicación Viral/inmunología
13.
Mol Biol Evol ; 36(2): 304-314, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30428072

RESUMEN

Gene duplication is seen as a major source of structural and functional divergence in genome evolution. Under the conventional models of sub or neofunctionalization, functional changes arise in one of the duplicates after duplication. However, we suggest here that the presence of a duplicated gene can result in functional changes to its interacting partners. We explore this hypothesis by in silico evolution of a heterodimer when one member of the interacting pair is duplicated. We examine how a range of selection pressures and protein structures leads to differential patterns of evolutionary divergence. We find that a surprising number of distinct evolutionary trajectories can be observed even in a simple three member system. Further, we observe that selection to correct dosage imbalance can affect the evolution of the initial function in several unexpected ways. For example, if a duplicate is under selective pressure to avoid binding its original binding partner, this can lead to changes in the binding interface of a nonduplicated interacting partner to exclude the duplicate. Hence, independent of the fate of the duplicate, its presence can impact how the original function operates. Additionally, we introduce a conceptual framework to describe how interacting partners cope with dosage imbalance after duplication. Contextualizing our results within this framework reveals that the evolutionary path taken by a duplicate's interacting partners is highly stochastic in nature. Consequently, the fate of duplicate genes may not only be controlled by their own ability to accumulate mutations but also by how interacting partners cope with them.


Asunto(s)
Evolución Molecular , Duplicación de Gen , Selección Genética , Adaptación Biológica , Simulación por Computador , Modelos Genéticos , Estabilidad Proteica
15.
Small ; 2(12): 1504-10, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17193013

RESUMEN

We report on the observation of an unexpected mechanism that controls conductivity at the 100-nm scale on track-etched polycarbonate membranes. Transport measurements of positively charged methyl viologen performed by absorption spectroscopy under various pH conditions demonstrate that for 100-nm-diameter pores at pH 2 conductivity is blocked, while at pH 5 the ions move through the membrane according to diffusion laws. An oppositely charged molecular ion, naphthalene disulfonate, in the same membrane, shows the opposite trend: diffusion of the negative ion at pH 2 and very low conductivity at pH 5. The influence of parameters such as ionic strength and membrane surface coating are also investigated. A theoretical study of the system shows that at the 100-nm scale the magnitude of the electric field in the vicinity of the pores is too small to account for the experimental observations; rather, it is the surface trapping of the mobile ion (Cl- or Na+) that gives rise to the observed control of the conductivity. This surprising effect has potential applications for high-throughput separation of large molecules and bio-organisms.


Asunto(s)
Conductividad Eléctrica , Modelos Químicos , Cloruros , Difusión , Concentración de Iones de Hidrógeno , Membranas Artificiales , Paraquat/química , Espectrofotometría Ultravioleta
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