Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Lab Anim ; 57(6): 611-622, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37382374

RESUMO

The laboratory mouse is used extensively for human disease modeling and preclinical therapeutic testing for efficacy, biodistribution, and toxicity. The variety of murine models available, and the ability to create new ones, eclipses all other species, but the size of mice and their organs create challenges for many in vivo studies. For pulmonary research, improved methods to access murine airways and lungs, and track substances administered to them, would be desirable. A nonsurgical endoscopic system with a camera, effectively a bronchoscope, coupled with a cryoimaging fluorescence microscopy technique to view the lungs in 3D, is described here that allows visualization of the procedure, including the anatomical location at which substances are instilled and fluorescence detection of those substances. We have applied it to bacterial infection studies to characterize better and optimize a chronic lung infection murine model in which we instill bacteria-laden agarose beads into the airways and lungs to extend the duration of the infection and inflammation. The use of the endoscope as guidance for placing a catheter into the airways is simple and quick, requiring only momentary sedation, and reduces post-procedural mortality compared with our previous instillation method that includes a trans-tracheal surgery. The endoscopic method improves speed and precision of delivery while reducing the stress on animals and the number of animals generated and used for experiments.


Assuntos
Broncoscopia , Pulmão , Humanos , Animais , Camundongos , Distribuição Tecidual , Pulmão/microbiologia
2.
J Genet Couns ; 32(1): 111-127, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36117419

RESUMO

Genetic counselors (GCs) provide risk assessment, education, and counseling about the genetic contribution to disease. To do so, they must effectively communicate, build rapport, and help patients make the best decisions for themselves and their families. Language barriers add a complex layer to this patient-provider dynamic. While interpreters serve as a primary solution when a patient and GC speak different languages, issues have been documented with these sessions, such as misinterpreted genetic terminology (Gutierrez et al., 2017). Having a GC with concordant language skills may help address these barriers. The purpose of this study was to assess Spanish-speaking patients' perspectives on communication, decision-making, and the interpersonal relationship developed with a bilingual GC in language concordant cancer genetic counseling sessions. Spanish-speaking patients, ages 18 or older, seen by a Spanish-speaking GC at a California public, safety-net hospital were eligible to participate in this study. Nine participants were interviewed via telephone by the bilingual researcher using a semi-structured interview guide to assess three domains: communication, decision-making, and interpersonal relationship. Analyses of interview transcripts identified themes within these three areas of focus: (1) participants felt all explanations were clear and they were not afraid to ask questions in the session, (2) participants experienced preference-concordant decision making, and (3) participants felt empowered and supported by the GC. Participants suggested that GCs working with Spanish-speaking patients in the future should consider group counseling sessions, engaging in outreach efforts to educate the Spanish-speaking community about genetics, and increasing the number of GCs who speak Spanish. These results demonstrate the positive experiences of Spanish-speaking patients in language concordant cancer genetic counseling sessions and further support the need for recruitment of Spanish-speaking individuals into the profession. Future research should further assess the experience of Spanish-speaking patients in language concordant sessions and address the role of cultural concordance in sessions.


Assuntos
Aconselhamento Genético , Neoplasias , Humanos , Adolescente , Idioma , Aconselhamento , Comunicação , Barreiras de Comunicação
3.
Am J Physiol Cell Physiol ; 323(4): C1112-C1120, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36062879

RESUMO

Disordered sleep experienced by people with cystic fibrosis (CF) suggest a possible disruption in circadian regulation being associated with the loss of cystic fibrosis transmembrane conductance regulator (Cftr) function. To test this hypothesis, circadian regulation was assessed in an F508del/F508del CF mouse model. CF mice exhibited significant alterations in both timing of locomotor activity and in mean activity per hour in both light-dark (LD) and dark-dark (DD) photoperiods compared with wild-type (WT) controls. It was also noted that in DD periodicity increased in CF mice, whereas shortening in WT mice as is expected. CF mice also exhibited altered timing of circadian gene expression and a reduction of melatonin production at all time points. Mechanistically, the role of microtubules in regulating these outcomes was explored. Mice lacking expression of tubulin polymerization promoting protein (Tppp) effectively mimicked CF mouse phenotypes with each measured outcome. Depleting expression of the microtubule regulatory protein histone deacetylase 6 (Hdac6) from CF mice (CF/Hdac6) resulted in the reversal of each phenotype to WT profiles. These data demonstrate an innate disruption of circadian regulation in CF mice and identify a novel microtubule-related mechanism leading to this disruption that can be targeted for therapeutic intervention.


Assuntos
Fibrose Cística , Melatonina , Animais , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Desacetilase 6 de Histona/genética , Desacetilase 6 de Histona/metabolismo , Camundongos , Tubulina (Proteína)/metabolismo
4.
J Assist Reprod Genet ; 39(9): 2043-2050, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35920991

RESUMO

PURPOSE: To identify specific likelihoods that an embryo will be classified as appropriate for transfer after preimplantation genetic testing for detection of a monogenic disorder (PGT-M), with or without preimplantation genetic testing for aneuploidy (PGT-A), separated by inheritance pattern. METHODS: Retrospective chart review of 181 selected PGT-M cycles performed at CooperGenomics in 2018 or 2019. For each cycle, the following main outcome data was collected: the number of embryos classified as affected with monogenic disease, the number detected to be chromosomally abnormal, the number that were recombinant, the number that had no result, and if applicable, the number which were aneuploid. RESULTS: There were significantly fewer embryos appropriate to consider for transfer when PGT-A was included for autosomal recessive and X-linked disorders. There were also fewer for autosomal dominant disorders, though this was not statistically significant. When PGT-A was not included, 45.8% of autosomal dominant, 69% of autosomal recessive, and 47.8% of X-linked embryos were appropriate to consider for transfer. When PGT-A analysis was included, 29% of autosomal dominant, 41% of autosomal recessive, and 22% of X-linked embryos were appropriate to consider for transfer. 96.8% of women elect to include PGT-A when pursuing PGT-M. CONCLUSION: This study resulted in specific likelihoods that an embryo would be found appropriate for clinicians and patients to consider for transfer based on the inheritance pattern of the monogenic disease being tested for and whether aneuploidy analysis was included.


Assuntos
Diagnóstico Pré-Implantação , Aneuploidia , Transferência Embrionária/métodos , Feminino , Testes Genéticos/métodos , Humanos , Gravidez , Diagnóstico Pré-Implantação/métodos , Estudos Retrospectivos
5.
Sci Rep ; 11(1): 17535, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475490

RESUMO

Cystic fibrosis (CF) is an autosomal recessive disease caused by dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR) protein, and is marked by an accumulation of mucus in affected airways resulting in persistent infection and chronic inflammation. Quantitative differences in inflammatory markers have been observed in CF patient serum, tracheal cells, and bronchoalveolar lavage fluid, in the absence of detectable infection, implying that absent CFTR function alone may result in dysregulated immune responses. To examine the relationship between absent CFTR and systemic inflammation, 22 analytes were measured in CF mice (F508del/F508del) sera using the MSD multiplex platform. Pro-inflammatory cytokines IL-2, TNF-α, IL-17α, IFN-γ, IL-1ß, and MIP-3α are significantly elevated in infection-naïve CF mice (p < 0.050). Anti-inflammatory cytokines IL-10 and IL-4 are also significantly increased (p = 0.00003, p = 0.004). Additionally, six general markers of inflammation are significantly different from non-CF controls (p < 0.050). To elucidate the effects of chronic infection on the CF inflammatory profile, we examined CF mice exposed to spontaneous Bordetella pseudohinzii infections. There are no statistical differences in nearly all inflammatory markers when compared to their infection-naïve CF counterparts, except in the Th2-derived IL-4 and IL-5 which demonstrate significant decreases following exposure (p = 0.046, p = 0.045). Lastly, following acute infection, CF mice demonstrate elevations in nearly all inflammatory markers, but exhibit a shortened return to uninfected levels over time, and suppression of Th1-derived IL-2 and IL-5 (p = 0.043, p = 0.011). These results imply that CF mice have a persistent inflammatory profile often indistinguishable from chronic infection, and a dysregulated humoral response during and following active infection.


Assuntos
Infecções por Bordetella/complicações , Bordetella/isolamento & purificação , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/microbiologia , Citocinas/sangue , Inflamação/diagnóstico , Mutação , Animais , Infecções por Bordetella/metabolismo , Infecções por Bordetella/microbiologia , Fibrose Cística/genética , Fibrose Cística/patologia , Modelos Animais de Doenças , Feminino , Inflamação/sangue , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
J Circadian Rhythms ; 19: 5, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34046074

RESUMO

The circadian timing system (CTS) is a complex set of cyclic cellular mechanisms which serve to synchronize discrete cell groups across multiple organ systems to adapt the bodys physiology to a (roughly) 24-hour clock. Many genes and hormones have been shown to be strongly associated with the CTS, some of which include the genes Bmal1, Period1, Period2, Cryptochrome1, and Cryptochrome2, and the hormone melatonin. Previous data suggest that microtubule dynamics play an important role in melatonin function as it relates to the CTS in vitro, though this relationship has never been explored in vivo. The purpose of this study was to determine whether disruption of microtubule regulation in C57Bl/6 mice results in measurable changes to the CTS. To study the potential effects of microtubule dynamics on the CTS in vivo, we utilized a mouse model of microtubule instability, knocked out for the tubulin polymerization promoting protein gene (Tppp -/-), comparing them to their wild type (WT) littermates in three categories: locomotor activity (in light/dark and dark/dark photoperiods), serial clock gene expression, and serial serum melatonin concentration. These comparisons showed differences in all three categories, including significant differences in locomotor characteristics under dark/dark conditions. Our findings support and extend previous reports that microtubule dynamics are a modulator of circadian rhythm regulation likely through a mechanism involving melatonin induced phase shifting.

7.
West J Nurs Res ; 42(12): 1042-1049, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32431239

RESUMO

Fatigue is a prevalent symptom associated with decreased quality of life and increased mortality in individuals with end stage renal disease (ESRD), yet causes of fatigue in individuals with ESRD remain poorly understood. We examined gene expression of Neuronal PAS Domain Protein 2 (NPAS2) in relation to patient-reported fatigue in 122 individuals with ESRD. Independent samples t-tests were used to examine NPAS2 gene expression profiles of: non-fatigue versus fatigue. Multivariable regression analyses were used to examine the relationship between fatigue and numerous variables including depression. Participants were approximately 58 years old (+/- 13.2 years), 78% African American (n = 95), and 72% male (n = 88). The phenotype of fatigue was not significantly associated with gene expression of NPAS2 but was significantly associated with depression (p< .001). This study suggests that further research should examine the causal mechanism between depression and fatigue in order to identify genetic factors that could explain the high comorbidity of depression and fatigue.


Assuntos
Depressão/complicações , Fadiga/genética , Falência Renal Crônica/genética , Qualidade de Vida/psicologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Comorbidade , Estudos Transversais , Feminino , Humanos , Falência Renal Crônica/etnologia , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Inquéritos e Questionários
8.
Biol Res Nurs ; 22(3): 319-325, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32390518

RESUMO

INTRODUCTION: Cystic fibrosis (CF) is an autosomal recessive disease that affects many organ systems, most notably the pulmonary and gastrointestinal systems. Through genome-wide association studies, multiple genetic regions modifying CF-related pulmonary and gastrointestinal symptoms have been identified, but translation of these findings to clinical benefit remains elusive. Symptom variation in CF patients has been associated with changes in health-related quality of life (HRQOL), but the relationship between CF symptom-modifying genetic loci and HRQOL has not been explored. The purpose of this study was to determine whether two previously identified genetic modifiers of CF-related pathology also modify the subscales of HRQOL. METHODS: HRQOL and genotype data were obtained and analyzed. Linear regressions were used to examine the amount of variance in HRQOL subscales that could be explained by genotype for each modifier locus. RESULTS: A significant regression equation was found between genotype for rs5952223, a variant near chrXq22-q23, and emotional functioning in a sample of 129 CF patients. DISCUSSION: These data suggest that genotype for this single-nucleotide polymorphism is associated with emotional functioning in CF patients and highlight this genetic region as a potential therapeutic target, irrespective of CF transmembrane conductance regulator genotype.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Fibrose Cística/fisiopatologia , Fibrose Cística/psicologia , Emoções , Genótipo , Adulto , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Ohio , Polimorfismo de Nucleotídeo Único
9.
Sci Rep ; 9(1): 19888, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882792

RESUMO

Synchronous assessment of multiple MRI contrast agents in a single scanning session would provide a new "multi-color" imaging capability similar to fluorescence imaging but with high spatiotemporal resolution and unlimited imaging depth. This multi-agent MRI technology would enable a whole new class of basic science and clinical MRI experiments that simultaneously explore multiple physiologic/molecular events in vivo. Unfortunately, conventional MRI acquisition techniques are only capable of detecting and quantifying one paramagnetic MRI contrast agent at a time. Herein, the Dual Contrast - Magnetic Resonance Fingerprinting (DC-MRF) methodology was extended for in vivo application and evaluated by simultaneously and dynamically mapping the intra-tumoral concentration of two MRI contrast agents (Gd-BOPTA and Dy-DOTA-azide) in a mouse glioma model. Co-registered gadolinium and dysprosium concentration maps were generated with sub-millimeter spatial resolution and acquired dynamically with just over 2-minute temporal resolution. Mean tumor Gd and Dy concentration measurements from both single agent and dual agent DC-MRF studies demonstrated significant correlations with ex vivo mass spectrometry elemental analyses. This initial in vivo study demonstrates the potential for DC-MRF to provide a useful dual-agent MRI platform.


Assuntos
Meios de Contraste , Gadolínio , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Meglumina/análogos & derivados , Neoplasias Experimentais/diagnóstico por imagem , Compostos Organometálicos , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacologia , Feminino , Gadolínio/química , Gadolínio/farmacologia , Humanos , Meglumina/química , Meglumina/farmacologia , Camundongos , Camundongos Nus , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia
10.
Sci Rep ; 9(1): 10282, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311988

RESUMO

The hypothesis of this study was that Hdac6 depletion would restore cystic fibrosis (CF) responses to bacterial challenge to more wild type profiles using a CF mouse model. CF mice harboring the F508del Cftr mutation respond to bacterial challenge with 25,000 CFU Pseudomonas aeruginosa embedded into agarose beads to slow clearance. CF mice respond significantly more aggressively to this challenge compared to WT mice with respect to bacterial clearance, weight loss, neutrophil recruitment, and MIP-2 production. Depletion of Hdac6 expression in the CF mice (CF/Hdac6) significantly improves these responses to more WT levels. Weight loss in response to infection is most severe in CF mice and significantly attenuated in CF/Hdac6 mice. Bacterial levels are reduced at a faster rate in CF/Hdac6 mice compared to CF mice where infection persists. Percent neutrophils in lung lavage fluid post-infection are significantly higher in CF mice, but returned to WT levels with CF/Hdac6 mice. Similarly, CF Mip-2 levels are restored to WT levels in the absence of Hdac6 expression. These data demonstrate that Hdac6 depletion restores CF responses to bacterial challenge to WT-like profiles and offer a potential therapeutic avenue for addressing inflammation and infection in CF airways independently of Cftr correction.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/microbiologia , Técnicas de Inativação de Genes/métodos , Desacetilase 6 de Histona/genética , Infecções por Pseudomonas/terapia , Animais , Carga Bacteriana , Líquido da Lavagem Broncoalveolar/imunologia , Quimiocina CXCL2/genética , Fibrose Cística/genética , Modelos Animais de Doenças , Camundongos , Neutrófilos/metabolismo , Infecções por Pseudomonas/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Deleção de Sequência , Redução de Peso
11.
J Assoc Nurses AIDS Care ; 30(4): 392-404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31241504

RESUMO

People living with HIV (PLWH) experience high rates of fatigue, which can be improved with physical activity. We examined relationships between HIV infection, fatigue, cardiorespiratory fitness, physical activity, and myokines. Twenty PLWH and 20 HIV-uninfected adults completed a fatigue assessment, a maximal cardiometabolic exercise test, serum measures of myokines, and wore an accelerometer for 7 days. Measures were completed at baseline, 3 months, and 6 months. At baseline, PLWH had more fatigue (4.7 ± 2.6 vs. 2.8 ± 2.5, p = .01) and higher peak ventilatory efficiency (VE/VCO2; 33 ± 5.5 vs. 30.2 ± 2.5; p = .06). Half of PLWH engaged in at least one 10-minute bout of physical activity in the previous week, compared with control subjects (65%). Over time, HIV infection and fibroblast growth factor 21 were associated with fatigue (p < .05). People living with HIV have more fatigue and a higher ventilatory efficiency; expression of fibroblast growth factor 21 may underpin this relationship.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Exercício Físico , Fadiga/etiologia , Fatores de Crescimento de Fibroblastos/sangue , Infecções por HIV/complicações , Interleucina-15/sangue , Interleucina-7/sangue , Acelerometria , Adulto , Estudos de Casos e Controles , Teste de Esforço , Feminino , Infecções por HIV/psicologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Dispositivos Eletrônicos Vestíveis
12.
J Circadian Rhythms ; 17: 2, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31065288

RESUMO

Cystic fibrosis (CF) is autosomal recessive disease that affects multiple body systems. CF patients often experience sleep disturbances, altered sleep patterns, and sleep apnea. Sleep in mammals is controlled in part by circadian clock genes, including Clock, Bmal1, Period1, Period2, Cryptochrome1, and Cryptochrome2. The purpose of this study was to gain a better understanding of the biological underpinnings of disordered sleep experienced in CF. To accomplish this, we evaluated circadian clock gene expression profiles in CF and wildtype mice, divided into two subgroups each based on sleep condition. One subgroup of each genotype was permitted to maintain their sleep-wake cycle while the other was deprived of sleep for six hours prior to sacrifice. Brain, skeletal muscle, jejunum, colon, lung and adipose tissues were collected from each mouse. Quantitative polymerase chain reaction (PCR) was used to quantify expression of Clock, Bmal1, Period1, Period2, Cryptochrome1 and Cryptochrome2, and expression levels were compared between study groups. Our comparisons showed distinct differences between the CF groups and the wildtype groups under both sleep conditions. Additionally, we found the CF mice that had been sleep deprived had severely dysregulated expression of all measured genes in the lung apart from Cry1. Our findings suggest that (1) disordered sleep in CF may be caused by circadian system dysregulation and (2) the loss of the cystic fibrosis transmembrane conductance regulator (CFTR) is a causative factor in the dysregulated circadian clock gene expression profiles of CF mice.

13.
J Prof Nurs ; 35(2): 89-92, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30902411

RESUMO

Nursing science is a diverse field of study, the scope of which has broadened to more fully incorporate genetics and genomics. In recent years, these topics have become focus areas for many nursing researchers. However, recent evidence suggests that doctoral level nursing students and nursing faculty may be underprepared to conduct independent research using genomic approaches. Furthermore, genetics and genomics are severely underrepresented in doctoral level nursing curricula across the United States. This article suggests a thorough, yet manageable three-part curriculum designed to educate doctoral level nursing students on genetics, genomics, and their use in nursing science. Recommendations are then given for the integration of the curriculum into existing nursing PhD programs.


Assuntos
Currículo , Educação de Pós-Graduação em Enfermagem , Genética/educação , Genômica/educação , Pesquisa em Enfermagem , Humanos , Estudantes de Enfermagem , Estados Unidos
14.
J Cyst Fibros ; 18(1): 127-134, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29937318

RESUMO

BACKGROUND: Pulmonary disease remains the primary cause of morbidity and mortality for individuals with cystic fibrosis (CF). Variants at a locus on the X-chromosome containing the type 2 angiotensin II receptor gene (AGTR2) were identified by a large GWAS as significantly associating with lung function in CF patients. We hypothesized that manipulating the angiotensin-signaling pathway may yield clinical benefit in CF. METHODS: Genetic subset analysis was conducted on a local CF cohort to extend the GWAS findings. Next, we evaluated pulmonary function in CF mice with a deleted AGTR2 gene, and in those who were given subcutaneous injections of PD123,319, a selective AGTR2 antagonist for 12 weeks beginning at weaning. RESULTS: The genetic subset analysis replicated the initial GWAS identified association, and confirmed the association of this locus with additional lung function parameters. Studies in genetically modified mice established that absence of the AGTR2 gene normalized pulmonary function indices in two independent CF mouse models. Further, we determined that pharmacologic antagonism of AGTR2 improved overall pulmonary function in CF mice to near wild-type levels. CONCLUSIONS: These results identify that reduced AGTR2 signaling is beneficial to CF lung function, and suggest the potential of manipulating the angiotensin-signaling pathway for treatment and/or prevention of CF pulmonary disease. Importantly, the beneficial effects were not CF gene mutation dependent, and were able to be reproduced with pharmacologic antagonism. As there are clinically approved drugs available to target the renin-angiotensin signaling system, these findings may be quickly translated to human clinical trials.


Assuntos
Fibrose Cística/genética , DNA/genética , Pneumopatias/prevenção & controle , Pulmão/fisiopatologia , Mutação , Receptor Tipo 2 de Angiotensina/genética , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacologia , Animais , Criança , Fibrose Cística/complicações , Fibrose Cística/metabolismo , Análise Mutacional de DNA , Modelos Animais de Doenças , Feminino , Seguimentos , Fluxo Expiratório Forçado/fisiologia , Genótipo , Humanos , Imidazóis/farmacologia , Pneumopatias/etiologia , Pneumopatias/genética , Masculino , Camundongos , Camundongos Knockout , Piridinas/farmacologia , Receptor Tipo 2 de Angiotensina/efeitos dos fármacos , Receptor Tipo 2 de Angiotensina/metabolismo , Estudos Retrospectivos
15.
Magn Reson Med ; 79(4): 2176-2182, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28796368

RESUMO

PURPOSE: The regularly incremented phase encoding-magnetic resonance fingerprinting (RIPE-MRF) method is introduced to limit the sensitivity of preclinical MRF assessments to pulsatile and respiratory motion artifacts. METHODS: As compared to previously reported standard Cartesian-MRF methods (SC-MRF), the proposed RIPE-MRF method uses a modified Cartesian trajectory that varies the acquired phase-encoding line within each dynamic MRF dataset. Phantoms and mice were scanned without gating or triggering on a 7T preclinical MRI scanner using the RIPE-MRF and SC-MRF methods. In vitro phantom longitudinal relaxation time (T1 ) and transverse relaxation time (T2 ) measurements, as well as in vivo liver assessments of artifact-to-noise ratio (ANR) and MRF-based T1 and T2 mean and standard deviation, were compared between the two methods (n = 5). RESULTS: RIPE-MRF showed significant ANR reductions in regions of pulsatility (P < 0.005) and respiratory motion (P < 0.0005). RIPE-MRF also exhibited improved precision in T1 and T2 measurements in comparison to the SC-MRF method (P < 0.05). The RIPE-MRF and SC-MRF methods displayed similar mean T1 and T2 estimates (difference in mean values < 10%). CONCLUSION: These results show that the RIPE-MRF method can provide effective motion artifact suppression with minimal impact on T1 and T2 accuracy for in vivo small animal MRI studies. Magn Reson Med 79:2176-2182, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Algoritmos , Anestesia , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Movimento (Física) , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes
16.
Sci Rep ; 7(1): 8431, 2017 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-28814732

RESUMO

Injectable Magnetic Resonance Imaging (MRI) contrast agents have been widely used to provide critical assessments of disease for both clinical and basic science imaging research studies. The scope of available MRI contrast agents has expanded over the years with the emergence of molecular imaging contrast agents specifically targeted to biological markers. Unfortunately, synergistic application of more than a single molecular contrast agent has been limited by MRI's ability to only dynamically measure a single agent at a time. In this study, a new Dual Contrast - Magnetic Resonance Fingerprinting (DC - MRF) methodology is described that can detect and independently quantify the local concentration of multiple MRI contrast agents following simultaneous administration. This "multi-color" MRI methodology provides the opportunity to monitor multiple molecular species simultaneously and provides a practical, quantitative imaging framework for the eventual clinical translation of molecular imaging contrast agents.


Assuntos
Meios de Contraste/administração & dosagem , Meios de Contraste/análise , Imageamento por Ressonância Magnética/métodos , Gadolínio/administração & dosagem , Gadolínio/análise , Humanos , Processamento de Imagem Assistida por Computador/métodos , Manganês/administração & dosagem , Manganês/análise , Modelos Teóricos , Imagens de Fantasmas , Reprodutibilidade dos Testes
17.
PLoS One ; 12(4): e0175467, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384265

RESUMO

Growth deficits are common in cystic fibrosis (CF), but their cause is complex, with contributions from exocrine pancreatic insufficiency, pulmonary complications, gastrointestinal obstructions, and endocrine abnormalities. The CF mouse model displays similar growth impairment despite exocrine pancreatic function and in the absence of chronic pulmonary infection. The high incidence of intestinal obstruction in the CF mouse has been suggested to significantly contribute to the observed growth deficits. Previous studies by our group have shown that restoration of the cystic fibrosis transmembrane conductance regulator (CFTR) in the intestinal epithelium prevents intestinal obstruction but does not improve growth. In this study, we further investigate growth deficits in CF and gut-corrected CF mice by assessing insulin-like growth factor 1 (IGF-1). IGF-1 levels were significantly decreased in CF and gut-corrected CF adult mice compared to wildtype littermates and were highly correlated with weight. Interestingly, perinatal IGF-1 levels were not significantly different between CF and wildtype littermates, even though growth deficits in CF mice could be detected late in gestation. Since CFTR has been suggested to play a role in water and nutrient exchange in the placenta through its interaction with aquaporins, we analyzed placental aquaporin expression in late-gestation CF and control littermates. While significant differences were observed in Aquaporin 9 expression in CF placentas in late gestation, there was no evidence of placental fluid exchange differences between CF and control littermates. The results from this study indicate that decreased IGF-1 levels are highly correlated with growth in CF mice, independent of CF intestinal obstruction. However, the perinatal growth deficits that are observed in CF mice are not due to decreased IGF-1 levels or differences in placenta-mediated fluid exchange. Further investigation is necessary to understand the etiology of early growth deficits in CF, as growth has been shown to be a significant factor in disease outcomes.


Assuntos
Fibrose Cística/fisiopatologia , Crescimento , Fator de Crescimento Insulin-Like I/genética , Animais , Fibrose Cística/complicações , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Feminino , Obstrução Intestinal/complicações , Camundongos , Camundongos Transgênicos , Placenta/metabolismo , Gravidez
18.
Respir Physiol Neurobiol ; 235: 88-94, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27756649

RESUMO

RATIONALE: Brainstem apolipoprotein AII (apoa2) mRNA expression correlates with apnea in breathing present in the adult C57Bl/6J (B6) sleep apnea model. OBJECTIVES: To test the hypothesis that the B6 apoa2 gene contributes to the trait, we performed plethysmographic testing in apoa2 knock out (KO: -/-) mice, an in situ brainstem-spinal cord preparation comparing KO to WT (+/+) mice, and B6xDBA recombinant inbred strains (RISs). MEASUREMENTS AND MAIN RESULTS: Apoa2 WT do, but KO and heterozygote (+/-) mice do not exhibit apnea during post-hypoxic breathing, measured in vivo. In the in situ model, pauses and instability in fictive phrenic bursting are substantially reduced in KO vs. WT preparations. In 24 RISs, apnea number in vivo was higher in strains with B6 apoa2 than with DBA apoa2 alleles. CONCLUSIONS: The B6 apoa2 polymorphism is directly involved in breath production, and its identification suggests a novel pathway influencing risk for adult sleep apnea.


Assuntos
Apneia/metabolismo , Apolipoproteína A-II/metabolismo , Predisposição Genética para Doença , Animais , Apolipoproteína A-II/genética , Tronco Encefálico/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Nervo Frênico/metabolismo , Pletismografia Total , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/metabolismo , Respiração , Técnicas de Cultura de Tecidos
19.
Genome Announc ; 4(5)2016 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-27738041

RESUMO

We report here the complete genome sequences of Bordetella flabilis and Bordetella bronchialis recovered from cultures of individuals with cystic fibrosis (CF), and "Bordetella pseudohinzii" recovered from a CF mouse model.

20.
Sleep Sci ; 9(2): 94-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656273

RESUMO

INTRODUCTION: Up to 84% of prematurely born infants suffer hypoxic, anoxic, and ischemic insults. Those infants with subsequent behavioral, motor or cognitive dysfunction represent 8-11% of all live births. Yet, no interventions employed during pregnancy attenuate risk of morbidity in those at-risk infants. Dietary supplementation with omega-3 polyunsaturated fatty acids (ω-3 PUFAs) has been shown to reduce stroke-induced neuropathology in rat models emulating this adverse clinical event. To extend those studies we sought to determine whether maternal dietary supplementation with ω-3 PUFAs would confer neuroprotection against hypoxia-induced neurochemical dysfunction in newborn rat pups exposed to repetitive hypoxic insults. METHODS: We provided pregnant rats with either a ω-3 PUFA enriched diet or else a standard rat chow diet. At postnatal day 7, pups were assigned randomly to either repetitive hypoxic insults or repetitive bursts of room air. On postnatal day 12, pups were sacrificed and brain dopamine levels characterized. RESULTS: Baseline brain dopamine levels did not differ between rat pups born to dams who received ω-3 PUFA enriched versus standard rat chow diets. Rat pups born to dams maintained on normal diets, who were exposed to five days of repetitive hypoxic insults, experienced a 57% reduction in striatal dopamine levels accompanied by significant apoptosis. In contrast, ω-3 PUFA-enriched newborn pups experienced no loss in striatal dopamine levels, and only minimal apoptosis. CONCLUSIONS: Our findings suggest that it may be feasible to confer neuroprotection against hypoxia-induced dopamine dysfunction to newborns likely to experience hypoxic insults. This could significantly improve the outcomes of those 8-11% of newborns who would otherwise experience hypoxia-induced behavioral, motor and cognitive dysfunction.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...