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1.
J Biol Chem ; 299(3): 102959, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36717078

RESUMO

The mammalian mitochondrial branched-chain ketoacid dehydrogenase (BCKD) complex is a multienzyme complex involved in the catabolism of branched-chain amino acids. BCKD is regulated by the BCKD kinase, or BCKDK, which binds to the E2 subunit of BCKD, phosphorylates its E1 subunit, and inhibits enzymatic activity. Inhibition of the BCKD complex results in increased levels of branched-chain amino acids and branched-chain ketoacids, and this buildup has been associated with heart failure, type 2 diabetes mellitus, and nonalcoholic fatty liver disease. To find BCKDK inhibitors for potential treatment of these diseases, we performed both NMR and virtual fragment screening and identified tetrazole-bearing fragments that bind BCKDK at multiple sites. Through structure-based virtual screening expanding from these fragments, the angiotensin receptor blocker class antihypertension drugs and angiotensin receptor blocker-like compounds were discovered to be potent BCKDK inhibitors, suggesting potential new avenues for heart failure treatment combining BCKDK inhibition and antihypertension.


Assuntos
3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida) , Antagonistas de Receptores de Angiotensina , Humanos , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Complexos Multienzimáticos/metabolismo , Insuficiência Cardíaca , Hipertensão
2.
J Exp Biol ; 226(Suppl_1)2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37021688

RESUMO

The functional capacities of animals are a primary factor determining survival in nature. In this context, understanding the biomechanical performance of animals can provide insight into diverse aspects of their biology, ranging from ecological distributions across habitat gradients to the evolutionary diversification of lineages. To survive and reproduce in the face of environmental pressures, animals must perform a wide range of tasks, some of which entail tradeoffs between competing demands. Moreover, the demands encountered by animals can change through ontogeny as they grow, sexually mature or migrate across environmental gradients. To understand how mechanisms that underlie functional performance contribute to survival and diversification across challenging and variable habitats, we have pursued diverse studies of the comparative biomechanics of amphidromous goby fishes across functional requirements ranging from prey capture and fast-start swimming to adhesion and waterfall climbing. The pan-tropical distribution of these fishes has provided opportunities for repeated testing of evolutionary hypotheses. By synthesizing data from the lab and field, across approaches spanning high-speed kinematics, selection trials, suction pressure recordings, mechanical property testing, muscle fiber-type measurements and physical modeling of bioinspired designs, we have clarified how multiple axes of variation in biomechanical performance associate with the ecological and evolutionary diversity of these fishes. Our studies of how these fishes meet both common and extreme functional demands add new, complementary perspectives to frameworks developed from other systems, and illustrate how integrating knowledge of the mechanical underpinnings of diverse aspects of performance can give critical insights into ecological and evolutionary questions.


Assuntos
Evolução Biológica , Peixes , Animais , Fenômenos Biomecânicos , Peixes/fisiologia , Natação , Ecossistema
3.
J Vet Med Educ ; 49(2): 141-150, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33950790

RESUMO

Policy changes in response to the coronavirus disease 2019 (COVID-19) pandemic at Iowa State University College of Veterinary Medicine (ISU-CVM) included the administrative directive that fourth-year (VM4) clinical rotations immediately transition from in-person to virtual format. This article summarizes the efforts, successes, and challenges experienced by ISU-CVM clinical faculty during this transition. Numerous data sources were reviewed, including college records and announcements, faculty survey results, and student rotation evaluations. Data were explored using quantitative and qualitative methods. Between March and July 2020, 36 faculty from 15 different clinical services invested approximately 5,000 hours in delivering virtual content to 165 VM4 students from ISU-CVM and Caribbean veterinary schools. With departmental, college, and university assistance, faculty effectively used educational technologies (Zoom, Canvas, Echo360) and developed adaptive and innovative methods for virtual content delivery. Virtual VM4 rotations were collectively well received and appreciated by students, and student evaluation scores for virtual rotations were statistically equivalent to or higher than those for the corresponding in-person rotations in the preceding year. Although certain hands-on skills could not be adequately acquired in a virtual environment, students gained theoretical knowledge and case-based problem-solving skills in the online format. Faculty reported satisfaction with their adaptability and resilience in these challenging circumstances. These findings demonstrate that ISU-CVM clinical faculty invested substantial time and effort to transition in-person clinical rotations to virtual format during the early COVID-19 pandemic. This is particularly noteworthy given that many of these same faculty simultaneously served as essential personnel managing clinical cases in the university's teaching hospital.


Assuntos
COVID-19 , Educação em Veterinária , Animais , COVID-19/epidemiologia , COVID-19/veterinária , Humanos , Iowa/epidemiologia , Pandemias , Universidades
4.
Anal Chem ; 93(8): 3770-3777, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33599129

RESUMO

Current state-of-the-art fission product separations frequently involve multiple independent separation columns and sample manipulation processes; to couple these processes together, multiple evaporation and transposition steps are often required. The addition of these steps results in lengthy separation times, increased analysis costs, the potential for sample loss, and release of radioactive contamination. We report a new semiautomated method for the rapid separation of U, Zr, Mo, Ba, Sr, Te, and lanthanide fission products from irradiated uranium samples. Chemical yields for U, Zr, Ba, Sr, Te and the lanthanides from less than 3-day old uranium fission product samples are consistently greater than 90%, while those of Mo are greater than 70%. This method minimizes the use and addition of oxidation and reduction reagents that often cause issues with retention and separation. Uranium dissolution and fission product separations using this single-pass method are achievable in under 2 h, representing a significant improvement over traditional gravimetric uranium fission product separation procedures.

5.
Nurs Outlook ; 69(6): 1030-1038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34625275

RESUMO

BACKGROUND: Advanced practice nurses (APNs) are well-positioned to function in research settings, however barriers to their engagement persist. Capacity-building through multisite research opportunities is an important strategy to overcome these barriers. PURPOSE: To describe the benefits and challenges of incorporating APNs in research and discuss opportunities for building capacity for nursing research. METHOD: Grounded in the experience of a nurse-led multisite longitudinal observational descriptive symptom study, field notes representing the research continuum were reviewed and categorized into themes reflecting benefits and challenges. FINDINGS: Uniform benefits of acquiring research knowledge and skills, participating in research activities, and engaging in professional development were experienced among APNs. Limited support for regulatory and research activities, inadequate financial infrastructure, and a perceived lack of value for APNs' professional growth were commonly encountered challenges. DISCUSSION: Establishment of an infrastructure that elevates benefits and mitigates challenges is necessary to effectively incorporate APNs in a research environment, build capacity, and advance nursing science.


Assuntos
Fortalecimento Institucional , Mentores , Profissionais de Enfermagem , Pesquisa em Enfermagem , Prática Avançada de Enfermagem , Humanos , Estudos Longitudinais , Alocação de Recursos
6.
J Vet Med Educ ; 48(1): 84-95, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32427541

RESUMO

Graphic organizers (GOs) are visual and spatial displays that facilitate learning by making conceptual relationships between content more apparent. It remains unknown whether GOs are more effective when completed by the teacher (instructor-provided [IP]) versus the learner (student-generated [SG]). A mixed-methods prospective randomized crossover trial was undertaken with veterinary students (n = 60) in an elective cardiology course. All students received identical content presented via weekly in-class lectures and were subsequently given study aids in either IP or SG format. One week later, students completed quizzes of content knowledge for each lesson and indicated amount of time spent studying. Crossover occurred such that groups of students alternated between receiving IP and SG. Quantitative and qualitative data were collected in the form of in-depth pre- and post-course surveys. Overall, there was no significant difference in quiz scores based on study aid type (p = .06). Students spent an average of 25% less time studying per lesson when using IP GOs compared with SG GOs (p < .001). Time spent studying for each quiz, as well as time period between date of studying and date of quiz, decreased significantly throughout the semester. Overall, students strongly preferred IP to SG format (p < .001); reasons listed included confidence in accuracy and completeness of information, as well as increased study efficiency. In an elective veterinary cardiology course, use of IP compared to SG format study aids resulted in higher study efficiency and student satisfaction with equivalent short-term learning outcomes.


Assuntos
Cardiologia , Educação em Veterinária , Animais , Humanos , Avaliação Educacional , Estudos Prospectivos , Estudantes
7.
J Vet Med Educ ; 48(4): 451-462, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32730170

RESUMO

The ideal study aid format for veterinary students remains unknown. Both graphic organizers (GOs) and flash cards (FCs) have shown utility for enhancing learning in specific contexts. A mixed-methods prospective randomized crossover trial was undertaken with veterinary students (n = 59) in an elective cardiology course. All students received identical content presented via weekly in-class lectures and were given study aids in either GO or FC format. One week later, students completed quizzes of content knowledge for each lesson and indicated amount of time spent studying. Crossover occurred such that groups of students alternated between receiving GOs and FCs. Quantitative and qualitative data were collected in the form of in-depth pre- and post-course surveys. Overall, there was no significant difference in quiz scores (p = .26) or time spent studying (p = .33) based on study aid type. Time spent studying for each quiz, as well as other measures of study habits, decreased significantly throughout the semester. Post-course survey responses showed overall higher student satisfaction for GOs compared to FCs (p = .022), as well as a shift in preference away from FCs throughout the semester (p = .03). Free-text survey responses revealed that individual students had strong preferences either for or against FCs in the context of their particular study habits. In an elective veterinary cardiology course, use of GO format compared to FC format study aids resulted in equivalent short-term learning outcomes and time spent studying, with each study aid format appealing to specific learning preferences of individual students.


Assuntos
Cardiologia , Educação em Veterinária , Animais , Avaliação Educacional , Aprendizagem , Estudos Prospectivos
8.
J Lipid Res ; 61(8): 1192-1202, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32482718

RESUMO

Lysosomal acid lipase (LAL) is a serine hydrolase that hydrolyzes cholesteryl ester (CE) and TGs delivered to the lysosomes into free cholesterol and fatty acids. LAL deficiency due to mutations in the LAL gene (LIPA) results in accumulation of TGs and cholesterol esters in various tissues of the body leading to pathological conditions such as Wolman's disease and CE storage disease (CESD). Here, we present the first crystal structure of recombinant human LAL (HLAL) to 2.6 Å resolution in its closed form. The crystal structure was enabled by mutating three of the six potential glycosylation sites. The overall structure of HLAL closely resembles that of the evolutionarily related human gastric lipase (HGL). It consists of a core domain belonging to the classical α/ß hydrolase-fold family with a classical catalytic triad (Ser-153, His-353, Asp-324), an oxyanion hole, and a "cap" domain, which regulates substrate entry to the catalytic site. Most significant structural differences between HLAL and HGL exist at the lid region. Deletion of the short helix, 238NLCFLLC244, at the lid region implied a possible role in regulating the highly hydrophobic substrate binding site from self-oligomerization during interfacial activation. We also performed molecular dynamic simulations of dog gastric lipase (lid-open form) and HLAL to gain insights and speculated a possible role of the human mutant, H274Y, leading to CESD.


Assuntos
Doença do Armazenamento de Colesterol Éster/enzimologia , Esterol Esterase/química , Esterol Esterase/metabolismo , Doença do Armazenamento de Colesterol Éster/genética , Cristalografia por Raios X , Glicosilação , Humanos , Modelos Moleculares , Mutação , Domínios Proteicos , Esterol Esterase/genética
9.
J Vet Med Educ ; 46(3): 353-366, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30702960

RESUMO

Graphic organizers (GOs) are visual and spatial displays, such as tables or charts, which facilitate learning by making conceptual relationships between content more apparent. We hypothesized that study aids in the form of GOs would lead to improved learning outcomes, study efficiency, and student satisfaction compared to traditional outline (OUT) format. A mixed-methods prospective randomized crossover trial was undertaken with veterinary students (n = 31) in an elective cardiology course. All students received identical content presented via weekly in-class lectures. Following 8 pre-designated lectures, students were given instructor-prepared study aids in either GO or OUT format. Students completed quizzes of content knowledge for each lesson and indicated amount of time spent studying. Crossover occurred such that groups of students alternated between receiving GO and OUT. Quantitative and qualitative data were collected in the form of in-depth pre- and post-course surveys. Quiz scores did not differ (p = .42) based on type of study aid provided (GO vs. OUT). Students spent an average of 17% less time studying per lesson when using GO compared to OUT (p = .05). Student satisfaction with both study aid formats was high, but students preferred GO over OUT in terms of study efficiency (p = .002), visual appeal (p < .001), ease of use (p < .004), and likelihood of referencing in the future (p < .001). In an elective veterinary cardiology course, use of GO compared to OUT format study aids resulted in higher study efficiency and student satisfaction with equivalent short-term learning outcomes.


Assuntos
Cardiologia/educação , Educação em Veterinária , Aprendizagem , Estudantes/psicologia , Animais , Avaliação Educacional , Humanos , Satisfação Pessoal , Estudos Prospectivos
10.
Pharmacogenet Genomics ; 28(2): 37-40, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29200408

RESUMO

OBJECTIVES: Myxomatous mitral valve disease (MMVD) is the most common heart disease in the dog. It is particularly common in the Cavalier King Charles Spaniel (CKCS) breed and affected dogs are frequently managed with angiotensin-converting enzyme inhibitors (ACE-I). We have previously identified a canine ACE gene polymorphism associated with a decrease in angiotensin-converting enzyme (ACE) activity. The aim of this study was to evaluate for the prevalence of the ACE polymorphism in CKCS with mitral valve disease and to determine whether the presence of the polymorphism is associated with alterations in ACE activity at different stages of cardiac disease. METHODS: Seventy-three dogs with a diagnosis of mitral valve disease were evaluated and a blood sample was drawn for ACE polymorphism genotyping and ACE activity measurement. RESULTS: Forty-three dogs were homozygous for the ACE polymorphism; five were heterozygous and 25 were homozygous wild type. The mean age and the median severity of disease were not different for dogs with the polymorphism and dogs with the wild-type sequence. The median baseline ACE activity was significantly lower for the ACE polymorphism (27.0 U/l) than the wild-type sequence dogs (31.0 U/l) (P=0.02). Dogs with more severe disease and the ACE polymorphism had significantly lower levels of ACE activity than dogs with the wild-type sequence (P=0.03). CONCLUSION: The CKCS appears to have a high prevalence of the ACE variant. Dogs with the ACE variant had lower levels of ACE activity even in more advanced mitral valve disease than dogs without the variant. The clinical significance of this finding and its impact on the need for ACE-I in dogs with the polymorphism and heart disease deserves further study.


Assuntos
Doenças das Valvas Cardíacas/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Animais , Cães , Genótipo , Doenças das Valvas Cardíacas/fisiopatologia , Doenças das Valvas Cardíacas/veterinária , Valva Mitral/fisiopatologia
11.
J Chem Ecol ; 44(1): 62-71, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29209932

RESUMO

Ecologists have long been interested in how the nutritional composition of leaves changes as they age, and whether this affects herbivore feeding preferences. As a consequence, the literature abounds with reports that younger leaves contain higher concentrations of nitrogen and plant secondary metabolites (PSMs) than do older leaves. Most of these studies, however, base their conclusions on average values that often mean little to herbivores. We examined this issue in the well-studied marsupial-eucalypt system, using Eucalyptus melliodora and captive common brushtail possums (Trichosurus vulpecula) offered branches from individual trees containing both young and mature leaves. Like many plants, the concentrations of N and PSMs differed among individual E. melliodora. Although young leaves were, on average, "better defended" by the PSM sideroxylonal than were mature leaves, some trees produced leaves that were relatively undefended at both ages. In response, possums chose different proportions of young and mature leaves depending on the chemistry of the individual tree. Possums did not always prefer leaves with lower concentrations of sideroxylonal (mature leaves) or those with higher concentrations of available N (young leaves). Instead, the sideroxylonal concentration of young leaves dictated their choice: possums preferred young leaves with low sideroxylonal concentrations, but not with high concentrations. By skewing their feeding toward trees producing young leaves with low concentrations of PSMs, possums may influence plant fitness. Researchers will detect these potentially important interactions only if they are aware that measuring variation among plants discloses more information than do average relationships.


Assuntos
Eucalyptus/química , Trichosurus/fisiologia , Animais , Benzofuranos/análise , Benzofuranos/farmacologia , Cromatografia Líquida de Alta Pressão , Eucalyptus/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Herbivoria , Masculino , Nitrogênio/análise , Floroglucinol/análogos & derivados , Floroglucinol/análise , Floroglucinol/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Fatores de Tempo
12.
J Pharmacol Exp Ther ; 361(2): 303-311, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28289077

RESUMO

Diabetic nephropathy remains an area of high unmet medical need, with current therapies that slow down, but do not prevent, the progression of disease. A reduced phosphorylation state of adenosine monophosphate-activated protein kinase (AMPK) has been correlated with diminished kidney function in both humans and animal models of renal disease. Here, we describe the identification of novel, potent, small molecule activators of AMPK that selectively activate AMPK heterotrimers containing the ß1 subunit. After confirming that human and rodent kidney predominately express AMPK ß1, we explore the effects of pharmacological activation of AMPK in the ZSF1 rat model of diabetic nephropathy. Chronic administration of these direct activators elevates the phosphorylation of AMPK in the kidney, without impacting blood glucose levels, and reduces the progression of proteinuria to a greater degree than the current standard of care, angiotensin-converting enzyme inhibitor ramipril. Further analyses of urine biomarkers and kidney tissue gene expression reveal AMPK activation leads to the modulation of multiple pathways implicated in kidney injury, including cellular hypertrophy, fibrosis, and oxidative stress. These results support the need for further investigation into the potential beneficial effects of AMPK activation in kidney disease.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aminopiridinas/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Ativadores de Enzimas/farmacologia , Indóis/farmacologia , Rim/efeitos dos fármacos , Aminopiridinas/uso terapêutico , Animais , Tamanho Celular , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Ativação Enzimática , Fibrose , Humanos , Indóis/uso terapêutico , Isoenzimas/metabolismo , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Macaca fascicularis , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Fosforilação , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , Ratos , Especificidade da Espécie
13.
Biochem J ; 473(5): 581-92, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26635351

RESUMO

AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase that serves as a pleotropic regulator of whole body energy homoeostasis. AMPK exists as a heterotrimeric complex, composed of a catalytic subunit (α) and two regulatory subunits (ß and γ), each present as multiple isoforms. In the present study, we compared the enzyme kinetics and allosteric modulation of six recombinant AMPK isoforms, α1ß1γ1, α1ß2γ1, α1ß2γ3, α2ß1γ1, α2ß2γ1 and α2ß2γ3 using known activators, A769662 and AMP. The α1-containing complexes exhibited higher specific activities and lower Km values for a widely used peptide substrate (SAMS) compared with α2-complexes. Surface plasmon resonance (SPR)-based direct binding measurements revealed biphasic binding modes with two distinct equilibrium binding constants for AMP, ADP and ATP across all isoforms tested. The α2-complexes were ∼25-fold more sensitive than α1-complexes to dephosphorylation of a critical threonine on their activation loop (pThr(172/174)). However, α2-complexes were more readily activated by AMP than α1-complexes. Compared with ß1-containing heterotrimers, ß2-containing AMPK isoforms are less sensitive to activation by A769662, a synthetic activator. These data demonstrate that ligand induced activation of AMPK isoforms may vary significantly based on their AMPK subunit composition. Our studies provide insights for the design of isoform-selective AMPK activators for the treatment of metabolic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/química , Monofosfato de Adenosina/química , Regulação Alostérica , Compostos de Bifenilo , Ativação Enzimática , Ativadores de Enzimas/química , Ensaios Enzimáticos , Humanos , Isoenzimas/química , Cinética , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Pironas/química , Proteínas Recombinantes/química , Tiofenos/química
14.
Bioorg Med Chem Lett ; 26(8): 1993-6, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26965858

RESUMO

Loss of LIPA activity leads to diseases such as Wolman's Disease and Cholesterol Ester Storage Disease. While it is possible to measure defects in LIPA protein levels, it is difficult to directly measure LIPA activity in cells. In order to measure LIPA activity directly we developed a LIPA specific activity based probe. LIPA is heavily glycosylated although it is unclear how glycosylation affects LIPA activity or function. Our probe is specific for a glycosylated form of LIPA in cells, although it labels purified LIPA regardless of glycosylation.


Assuntos
Sondas Moleculares/análise , Sondas Moleculares/metabolismo , Esterol Esterase/química , Esterol Esterase/metabolismo , Glicosilação , Humanos , Simulação de Acoplamento Molecular , Sondas Moleculares/síntese química , Sondas Moleculares/química , Estrutura Molecular
15.
Biol Blood Marrow Transplant ; 21(9): 1612-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26025482

RESUMO

Busulfan (Bu) is widely used in conditioning regimens for infants undergoing allogeneic hematopoietic progenitor cell transplantation (HPCT), but the best approach to administer Bu in this population is still unknown. Here, we report a single-center experience of the use of a test dose to guide dose adjustment of intravenous (i.v.) Bu therapy in infants. Between 2004 and 2013, 33 infants younger than 1 year with nonmalignant conditions received allogeneic peripheral blood or cord blood HPCT after a reduced-intensity conditioning (RIC) regimen consisting of fludarabine, antithymocyte globulin, and 2 single daily doses of i.v. Bu. Pharmacokinetic results of a test dose of i.v. Bu (.8 mg/kg) were used to determine the dose of 2 single daily i.v. Bu regimen doses, adjusted to target an area under the curve (AUC) of 4000 µMol*minute per day in a first cohort (n = 12) and 5000 µMol*minute in a second cohort (n = 21). The mean Bu clearance in our infant patients was found to be 3.67 ± 1.03 mL/minute/kg, and the test dose clearance was highly predictive of the regimen dose clearance. The mean AUC achieved after the first single daily regimen dose was 3951 ± 1239 in the AUC 4000 cohort and 4884 ± 766 for the AUC 5000 cohort. No patient in either cohort developed hepatic sinusoidal obstructive syndrome or seizures attributable to Bu. Primary graft failure occurred in 4 patients and secondary graft failure occurred in 3, predominantly in the AUC 4000 cohort (6 of 7). Among the engrafted patients (n = 28), 16 achieved full donor chimerism and 9 patients attained stable mixed chimerism. Overall survival of patients at 6 years after transplantation was 59.5% for the AUC 4000 cohort and 85.4% for the AUC 5000 cohort, with primary graft failure in the first cohort being a major contributor to morbidity. Logistic regression analysis showed that the risk of graft failure increased significantly if cord blood hematopoietic progenitor cells were used or if total Bu exposure was below 4000 µMol*minute per day for 2 days. The difference in clinical outcomes between the 2 cohorts supports the conclusion that targeting a higher Bu AUC of 5000 µMol*minute per day for 2 days improves donor engraftment in infants with nonmalignant conditions undergoing RIC HPCT without increasing toxicity. Measuring i.v. Bu pharmokinetics using a test dose allows timely adjustment of single daily regimen doses and optimization of total Bu exposure, resulting in an effective and safe regimen for these infants.


Assuntos
Bussulfano/administração & dosagem , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Transplante de Células-Tronco Hematopoéticas , Condicionamento Pré-Transplante , Aloenxertos , Bussulfano/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Taxa de Sobrevida
16.
J Pharmacol Exp Ther ; 353(2): 288-98, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25698787

RESUMO

Small vessel vasculitis is a life-threatening condition and patients typically present with renal and pulmonary injury. Disease pathogenesis is associated with neutrophil accumulation, activation, and oxidative damage, the latter being driven in large part by myeloperoxidase (MPO), which generates hypochlorous acid among other oxidants. MPO has been associated with vasculitis, disseminated vascular inflammation typically involving pulmonary and renal microvasculature and often resulting in critical consequences. MPO contributes to vascular injury by 1) catabolizing nitric oxide, impairing vasomotor function; 2) causing oxidative damage to lipoproteins and endothelial cells, leading to atherosclerosis; and 3) stimulating formation of neutrophil extracellular traps, resulting in vessel occlusion and thrombosis. Here we report a selective 2-thiouracil mechanism-based MPO inhibitor (PF-1355 [2-(6-(2,5-dimethoxyphenyl)-4-oxo-2-thioxo-3,4-dihydropyrimidin-1(2H)-yl)acetamide) and demonstrate that MPO is a critical mediator of vasculitis in mouse disease models. A pharmacokinetic/pharmacodynamic response model of PF-1355 exposure in relation with MPO activity was derived from mouse peritonitis. The contribution of MPO activity to vasculitis was then examined in an immune complex model of pulmonary disease. Oral administration of PF-1355 reduced plasma MPO activity, vascular edema, neutrophil recruitment, and elevated circulating cytokines. In a model of anti-glomerular basement membrane disease, formerly known as Goodpasture disease, albuminuria and chronic renal dysfunction were completely suppressed by PF-1355 treatment. This study shows that MPO activity is critical in driving immune complex vasculitis and provides confidence in testing the hypothesis that MPO inhibition will provide benefit in treating human vasculitic diseases.


Assuntos
Acetamidas/farmacologia , Inibidores Enzimáticos/farmacologia , Membrana Basal Glomerular/efeitos dos fármacos , Glomerulonefrite/prevenção & controle , Doenças do Complexo Imune/prevenção & controle , Peroxidase/antagonistas & inibidores , Pirimidinas/farmacologia , Pirimidinonas/farmacologia , Vasculite/prevenção & controle , Animais , Membrana Basal Glomerular/patologia , Glomerulonefrite/enzimologia , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Humanos , Doenças do Complexo Imune/enzimologia , Doenças do Complexo Imune/imunologia , Doenças do Complexo Imune/patologia , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Vasculite/enzimologia , Vasculite/imunologia , Vasculite/patologia
17.
Protein Expr Purif ; 110: 22-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25620107

RESUMO

Lysosomal acid lipase (LAL) is a serine hydrolase which hydrolyzes cholesteryl ester and triglycerides delivered to the lysosomes into free cholesterol and free fatty acids. Mutations in the LAL gene (LIPA) result in accumulation of triglycerides and cholesterol esters in various tissues of the body, leading to pathological conditions such as Wolman's disease (WD) and cholesteryl ester storage disease (CESD). CESD patients homozygous for His295Tyr (H295Y) mutation have less than 5% of normal LAL activity. To shed light on the molecular basis for this loss-of-function phenotype, we have generated the recombinant H295Y enzyme and studied its biophysical and biochemical properties. No significant differences were observed in the expression levels or glycosylation patterns between the mutant and the wild type LAL. However, the H295Y mutant displayed only residual enzymatic activity (<5%) compared to the wild type. While wild type LAL is mostly a monomer at pH 5.0, the vast majority H295Y exists as a high molecular soluble aggregate. Besides, the H295Y mutant has a 20°C lower melting temperature compared to the wild type. Transient expression studies in WD fibroblasts showed that mutation of His295 to other amino acids resulted in a significant loss of enzymatic activity. A homology model of LAL revealed that His295 is located on an α-helix of the cap domain and could be important for tethering it to its core domain. The observed loss-of-function phenotype in CESD patients might arise from a combination of protein destabilization and the shift to a non-functional soluble aggregate.


Assuntos
Lisossomos/enzimologia , Esterol Esterase/genética , Doença de Wolman/enzimologia , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Ésteres do Colesterol/química , Ésteres do Colesterol/metabolismo , Clonagem Molecular , Fibroblastos/metabolismo , Fibroblastos/patologia , Expressão Gênica , Glicosilação , Humanos , Cinética , Metabolismo dos Lipídeos , Lisossomos/patologia , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Plasmídeos/química , Plasmídeos/metabolismo , Agregados Proteicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Células Sf9 , Spodoptera , Esterol Esterase/isolamento & purificação , Esterol Esterase/metabolismo , Doença de Wolman/genética , Doença de Wolman/patologia
18.
J Contin Educ Nurs ; 45(1): 35-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24369754

RESUMO

This article describes the ethical principles of autonomy, beneficence, and justice within the nurse researcher-participant relationship as these principles relate to the informed consent process for research. Within this process, the nurse is confronted with a dual role. This article describes how nurses, who are in the dual role of care provider and researcher, can apply these ethical principles to their practice in conjunction with the American Nurses Association's code of ethics for nurses. This article also describes, as an element of ethical practice, the importance of using participant-centered quality measures to aid informed decision making of participants in research. In addition, the article provides strategies for improving the informed consent process in nursing research. Finally, case scenarios are discussed, along with the application of ethical principles within the awareness of the dual role of the nurse as care provider and researcher.


Assuntos
Ética em Enfermagem , Consentimento Livre e Esclarecido/ética , Papel do Profissional de Enfermagem , Relações Enfermeiro-Paciente/ética , Pesquisa em Enfermagem/ética , Pesquisadores/ética , Humanos
19.
Ecol Evol ; 14(2): e10846, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38327688

RESUMO

Microplastics (MPs) have become an environmental concern in recent years, with most research focused on the physiological effects of exposure. Comparatively little consideration has been given to the potential behavioral impacts of exposure, which may also have fitness consequences for individuals. Moreover, MPs can serve as vectors for endocrine-disrupting chemicals and other locally co-occurring contaminants known to impair behavioral responses. This project aimed to determine whether MPs alone or in association with a common environmental EDC (17-alpha ethinyl estradiol; EE2) alter reproductive behavior and decision-making in fish. Male and female fathead minnows (Pimephales promelas) were exposed to MPs associated with either a low (10 ng/L; MPEE2 10) or high (50 ng/L, MPEE2 50) concentration of EE2, or MPs without EE2 (MPvirgin) for 30 days via a dietary feeding protocol. Behavioral trials were conducted on Day 31 to determine the effects of exposure on male-female social interactions. The expression of male sexually selected traits, including courtship, was unaffected by exposure. However, non-exposed females in all treatment groups trended toward discrimination against exposed males, which reached statistical significance for the MPEE2 50 group. Female fish exposed to MPs, alone or in association with EE2, were equally likely to approach and associate with non-exposed and exposed males. The results from this study suggest that MPs may alter social behavior in fishes and that the behavioral impacts of exposure may be more strongly pronounced in females than males. Such individual-level changes in fitness have the potential to impact population size, with downstream effects on the broader aquatic community.

20.
Cancer Nurs ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38447041

RESUMO

BACKGROUND: Children with cancer and other serious illnesses experience symptom burden during hematopoietic stem cell transplantation and chimeric antigen receptor T-cell therapy, yet limited research has characterized how these symptoms interact with overall quality of life over time. OBJECTIVE: The aim of this study was to examine the longitudinal relationship between symptoms and quality of life in children receiving hematopoietic stem cell transplantation or chimeric antigen receptor T-cell therapy. METHODS: A multisite study design was used to collect symptom and quality of life information at pre-cell infusion and days +30, +60, and +90 from children (N = 140) receiving hematopoietic stem cell transplantation and chimeric antigen receptor T-cell therapy. A longitudinal parallel process model was used to characterize the relationship between symptoms and quality of life. RESULTS: Children (mean age, 8.4 years) received allogeneic transplant (57.9%), autologous transplant (25.7%), or chimeric antigen receptor T-cell therapy (16.4%). Symptom prevalence was highest at baseline (>50%) for pain, fatigue, nausea, vomiting, and low appetite. Quality of life scores were worse at baseline (mean [SD], 69.5 [15.8]) and improved by 10 points by day +90. The longitudinal model indicated high symptom prevalence at baseline predicted worse quality of life at both baseline and day +90. CONCLUSIONS: Children felt worse early in the treatment trajectory and improved by day +90. The level of symptom burden predicted the overall quality of life at all time points. IMPLICATIONS FOR PRACTICE: Children experiencing high symptom burden should receive frequent assessment and enhanced symptom management throughout the treatment trajectory to mitigate negative impacts on quality of life.

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