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1.
Drug Test Anal ; 15(5): 539-550, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36648419

RESUMO

Developing methods to rapidly screen for novel synthetic 2-benzylbenzimidazole opioids, also known as nitazenes, has become increasingly important due to their high potency. These compounds have potency comparable or exceeding that of fentanyl by up to 10 times and have been implicated in approximately 5% of all drug overdose deaths in the United States in 2021. This paper details the authenticity determination of suspect tablets and the identification of three nitazene analogs (N-pyrrolidino etonitazene, isotonitazene, and etodesnitazene) in suspect tablets seized at a mail facility using Raman and surface-enhanced Raman scattering (SERS) with handheld devices, portable Fourier transform infrared spectrometer (FT-IR), and a direct analysis in real-time ambient ionization coupled to a thermal desorption unit and a mass spectrometer (DART-TD-MS). These methods are rapid and excellent for screening opioids in suspect tablets but could not fully determine the exact structure of some of the nitazene analogs present due to spectral similarities or similar fragmentation patterns. Liquid chromatography-mass spectrometry (LC-MS) confirmed the presence of these nitazene compounds in addition to other opioids/drugs that were in trace quantities. The quantitative high-performance liquid chromatography coupled with ultraviolet (HPLC-UV) detection experiments determined that the suspect tablets contained an average of 0.817 mg of N-pyrrolidino etonitazene per tablet. The results obtained reveal that the simultaneous deployment of these complementary and orthogonal portable analytical techniques as part of a workflow allows suspect tablets to be screened and nitazene-type drugs to be identified in suspect counterfeit tablets at remote sampling sites.


Assuntos
Análise Espectral Raman , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida , Comprimidos
2.
Early Child Educ J ; : 1-17, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35974977

RESUMO

High-quality Early Childhood Education and Care (ECEC) is an important component of thriving communities. It is central to the socio-emotional and intellectual growth of young children, to the ability of parents to go to work, and to the ability of employers to find and retain workers. Despite this centrality, there is a profound shortage of ECEC in many communities, which has only been made worse by COVID-19. This study took place in rural Kentucky pre-pandemic, where approximately half of all residents lived in "childcare deserts"-a situation facing a growing number of communities. This research demonstrates that while financial factors affect the undersupply of childcare in a single community, there are also additional, more opaque, and under-theorized factors at play. Specifically, we argue that misconceptions around families' ability and willingness to pay for ECEC, what families prioritize in an ECEC setting, and ambiguous terminology result in misunderstandings and miscommunication that, in turn, affect perceived solutions to the problem of the childcare desert. In short, when different stakeholders use different language and assumptions to describe their goals and ideas about ECEC, it is hard to reach community consensus about how to add the high-quality options that families desire and value. Drawing upon survey and interview data collected from parents and childcare providers, as well as local newspaper articles and during community forums, we uncover barriers that may hinder efforts to strengthen ECEC options; notably, many barriers are surmountable. Ultimately, this research points to concrete steps that communities can take to help bolster ECEC and, thus, communities at large.

3.
Brain Behav ; 10(9): e01774, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32767655

RESUMO

Personality traits and diet can be used to predict if a person is predisposed to disordered eating. Results of this study demonstrate a strong significant relationship between the personality trait of selflessness, diet group, and disordered eating. Vegans were most likely to display selflessness tendencies associated with disordered eating; however when selflessness was controlled for, vegans displayed substantially less disordered eating pathology than non-vegetarians. OBJECTIVE: To explore the relationship between diet group (non-vegetarian, semi-vegetarian, true-vegetarian, and vegan) and disordered eating while investigating to what extent personality trait of selflessness mediates the relationship between diet group and disordered eating. METHOD: Cross-sectional data from 634 Australian nonclinical women who completed a series of online questionnaires including measures of diet group, disordered eating, and selflessness were used to examine associations between diet, personality (selflessness), and disordered eating. RESULTS: Selflessness was found to be a significant positive predictor of disordered eating. Results confirm that selflessness played a suppressing role in the relationship between the vegan diet group and disordered eating, when compared to non-vegetarians. Surprisingly, vegans displayed significantly less disordered eating than non-vegetarians and semi-vegetarians. DISCUSSION: Results of the current study imply that the role of selflessness on disordered eating, when broken down across diet group, may be more complex than first thought. If replicated, these results suggest that targeted treatment of selflessness in different diet groups may improve treatment outcomes for disordered eating. Further research should explore why diet groups differ in terms of selflessness and how this impacts disordered eating.


Assuntos
Dieta Vegetariana , Transtornos da Alimentação e da Ingestão de Alimentos , Austrália , Estudos Transversais , Dieta , Comportamento Alimentar , Feminino , Humanos
4.
Ophthalmol Glaucoma ; 3(3): 196-201, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32672615

RESUMO

PURPOSE: Patients with myopia are at increased risk for the development of glaucoma. The inability to correct for axial length on spectral-domain (SD) OCT translates into lower signal strength and scan reliability in patients with high axial myopia. We evaluated the effectiveness of a contact lens to increase the signal strength and to assess optic nerve dimensions and nerve fiber layer (NFL) thickness using SD OCT in patients with glaucoma or who are glaucoma suspects with high axial myopia. DESIGN: Single-center, prospective, interventional study. PARTICIPANTS: Patients with axial lengths of more than 25.5 mm with a diagnosis of glaucoma or glaucoma suspect. METHODS: The optic nerve cube 200×200 scan using the Cirrus SD OCT 400 (Carl Zeiss Meditec, Inc., Dublin, CA) was carried out first without the use of a contact lens and then repeated with placement of the contact lens to correct for the spherical equivalent of the refractive error. MAIN OUTCOME MEASURES: The primary outcome measure was the change in the average NFL thickness before and after use of the contact lens. Secondary outcome measures included the changes in cup volume, disc area, and rim area on OCT. RESULTS: Twelve patients were recruited (20 eyes); the average axial length was 27.06 mm, and the average signal strength interval increased by 1.73 (P = 0.001). With the use of a contact lens, the average NFL thickness was significantly thicker. None of the changes in the secondary outcome measures were significant: rim area, cup volume, or disc area. CONCLUSIONS: Based on our data, the use of a contact lens statistically improved the signal strength and average NFL thickness of the SD OCT scan. The ability to capture the perimeter of the optic disc accurately can be limited in the setting of peripapillary atrophy, which was present in all but 2 participants. Future studies with a larger number of participants and a wider range of axial myopia to discern if contact lens correction has a greater effect on the highest axial lengths are needed.


Assuntos
Lentes de Contato , Glaucoma/diagnóstico , Pressão Intraocular/fisiologia , Miopia Degenerativa/diagnóstico , Nervo Óptico/patologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Glaucoma/complicações , Glaucoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miopia Degenerativa/complicações , Miopia Degenerativa/fisiopatologia , Fibras Nervosas/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
5.
Biophys J ; 117(2): 269-280, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31266635

RESUMO

The γ-crystallins of the eye lens nucleus are among the longest-lived proteins in the human body. Synthesized in utero, they must remain folded and soluble throughout adulthood to maintain lens transparency and avoid cataracts. γD- and γS-crystallin are two major monomeric crystallins of the human lens. γD-crystallin is concentrated in the oldest lens fiber cells, the lens nucleus, whereas γS-crystallin is concentrated in the younger cells of the lens cortex. The kinetic stability parameters of these two-domain proteins and their isolated domains were determined and compared. Kinetic unfolding experiments monitored by fluorescence spectroscopy in varying concentrations of guanidinium chloride were used to extrapolate unfolding rate constants and half-lives of the crystallins in the absence of the denaturant. Consistent with their long lifespans in the lens, extrapolated half-lives for the initial unfolding step were on the timescale of years. Both proteins' isolated N-terminal domains were less kinetically stable than their respective C-terminal domains at denaturant concentrations predicted to disrupt the domain interface, but at low denaturant concentrations, the relative kinetic stabilities were reversed. Cataract-associated aggregation has been shown to proceed from partially unfolded intermediates in these proteins; their extreme kinetic stability likely evolved to protect the lens from the initiation of aggregation reactions. Our findings indicate that the domain interface is the source of significant kinetic stability. The gene duplication and fusion event that produced the modern two-domain architecture of vertebrate lens crystallins may be the origin of their high kinetic as well as thermodynamic stability.


Assuntos
Cristalino/metabolismo , gama-Cristalinas/química , gama-Cristalinas/metabolismo , Humanos , Cinética , Modelos Moleculares , Domínios Proteicos , Dobramento de Proteína , Estabilidade Proteica , Temperatura , Fatores de Tempo
6.
Patient Educ Couns ; 101(8): 1403-1409, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29550294

RESUMO

OBJECTIVE: To identify communication patterns of Registered Nurses regarding patients' use of complementary therapies. METHODS: A cross-sectional online survey conducted in 2017 recruited Australian Registered Nurses working in any area of nursing. RESULTS: Responses of 614 Registered Nurses were analysed. Patient-initiated discussion of complementary therapies were common for 77% of nurses; nurse-initiated discussions were perceived by 73% (sometimes/almost always/always). Nurses' personal use of complementary therapies predicted discussion with patients and education-based, oncology, or aged care/rehabilitation nurses were most likely to initiate dialogue. Many (55%) did not 'recommend' a particular therapy, although 12% 'almost always/always' did so. Four out of five nurses (84%) documented patients' use and communicated with medical/nursing colleagues about this use. Conversely, 61% 'never' or 'almost never' communicated with a complementary therapy practitioner. CONCLUSION: Nurses working in Australia often discuss complementary therapies, however they rarely specifically recommend their use. Their workplace environment and clinical context influenced nurses' willingness to communicate about complementary therapy use. PRACTICE IMPLICATIONS EVIDENCE: suggests the need for policy development to promote communication between mainstream healthcare providers and complementary therapy practitioners to support the delivery of safe, high quality patient care.


Assuntos
Terapias Complementares , Conhecimentos, Atitudes e Prática em Saúde , Relações Enfermeiro-Paciente , Adulto , Austrália , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Inquéritos e Questionários
7.
J Adv Nurs ; 74(7): 1649-1658, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29493807

RESUMO

AIM: To explore Registered Nurses' attitudes and behaviour towards patients' use of complementary therapies. BACKGROUND: Despite high rates of use of complementary therapies by the general population, little is known of how nurses respond to patients' use of these therapies. DESIGN: A two-phase sequential exploratory mixed methods design. METHODS: Nineteen Registered Nurses working in Australia participated in a semi-structured interview in 2015-2016 and emerging themes informed the development of a quantitative survey instrument administered online nationwide in 2016. FINDINGS: Emerging key themes "Promoting safe care"; "Seeking complementary therapies knowledge";" Supporting holistic health care"; and "Integrating complementary therapies in practice" were reflected in survey results. Survey responses (N = 614) revealed >90% agreement that complementary therapies align with a holistic view of health and that patients have the right to use them. Most nurses (77.5%) discussed complementary therapies with patients and 91.8% believed nurses should have some understanding of the area. One-third did not recommend complementary therapies and there was a lack of overall consensus as to whether these therapies should be integrated into nursing practice. Nurses with training in complementary therapies held more positive views than those without. CONCLUSION: Nurses were generally supportive of patients' interest in complementary therapies, although their primary concern was safety of the patient. Despite broad acceptance that nurses should have a basic understanding of complementary therapies, there was a lack of consensus about recommendation, integration into nursing practice and referral. Further research should explore how nurses can maintain safe, patient-centred care in the evolving pluralistic healthcare system.


Assuntos
Atitude do Pessoal de Saúde , Terapias Complementares , Relações Enfermeiro-Paciente , Enfermeiras e Enfermeiros/psicologia , Adulto , Idoso , Austrália , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Saúde Holística , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Inquéritos e Questionários
8.
Circ Genom Precis Med ; 11(2): e001805, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32966096

RESUMO

BACKGROUND: The adult mammalian heart has little regenerative capacity after myocardial infarction (MI), whereas neonatal mouse heart regenerates without scarring or dysfunction. However, the underlying pathways are poorly defined. We sought to derive insights into the pathways regulating neonatal development of the mouse heart and cardiac regeneration post-MI. METHODS AND RESULTS: Total RNA-seq of mouse heart through the first 10 days of postnatal life (referred to as P3, P5, P10) revealed a previously unobserved transition in microRNA (miRNA) expression between P3 and P5 associated specifically with altered expression of protein-coding genes on the focal adhesion pathway and cessation of cardiomyocyte cell division. We found profound changes in the coding and noncoding transcriptome after neonatal MI, with evidence of essentially complete healing by P10. Over two-thirds of each of the messenger RNAs, long noncoding RNAs, and miRNAs that were differentially expressed in the post-MI heart were differentially expressed during normal postnatal development, suggesting a common regulatory pathway for normal cardiac development and post-MI cardiac regeneration. We selected exemplars of miRNAs implicated in our data set as regulators of cardiomyocyte proliferation. Several of these showed evidence of a functional influence on mouse cardiomyocyte cell division. In addition, a subset of these miRNAs, miR-144-3p, miR-195a-5p, miR-451a, and miR-6240 showed evidence of functional conservation in human cardiomyocytes. CONCLUSIONS: The sets of messenger RNAs, miRNAs, and long noncoding RNAs that we report here merit further investigation as gatekeepers of cell division in the postnatal heart and as targets for extension of the period of cardiac regeneration beyond the neonatal period.

9.
Int J Nurs Stud ; 69: 47-56, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28167377

RESUMO

BACKGROUND: The use of complementary therapies is becoming increasingly prevalent. This has important implications for nurses in terms of patient care and safety. OBJECTIVE: The aim of this meta-synthesis is to review critically, appraise and synthesize the existing qualitative research to develop a new, more substantial interpretation of nurses' attitudes regarding the, use of complementary therapies by patients. DATA SOURCES: A search of relevant articles published in English between, January 2000 and December 2015 was conducted using the following, electronic databases; MEDLINE, CINAHL and AMED. Reference lists of selected papers and grey literature were also interrogated for pertinent, studies. DESIGN: This review is reported according to the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) guidelines. Data were extracted and analysed using a thematic synthesis process. RESULTS: Fifteen articles were included in this review. Five analytical themes emerged from the data relating to nurses' attitude towards complementary therapies: the strengths and weaknesses of conventional medicine; Complementary therapies as a way to enhance nursing practice; patient empowerment and patient-centeredness; cultural barriers and enablers to integration; and structural barriers and enablers to integration. DISCUSSION: Nurses' support for complementary therapies is not an attempt to challenge mainstream medicine but rather an endeavour to improve the quality of care available to patients. There are, however, a number of barriers to nurses' support including institutional culture and clinical context, as well as time and knowledge limitations. CONCLUSION: Some nurses promote complementary therapies as an opportunity to personalise care and practice in a humanistic way. Yet, nurses have very limited education in this field and a lack of professional frameworks to assist them. The nursing profession needs to consider how to address current deficiencies in meeting the growing use of complementary therapies by patients.


Assuntos
Atitude do Pessoal de Saúde , Terapias Complementares , Recursos Humanos de Enfermagem/psicologia , Humanos , Assistência Centrada no Paciente , Poder Psicológico
10.
Biochem Mol Biol Educ ; 43(4): 233-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26148149

RESUMO

Modern research often requires collaboration of experts in fields, such as math, chemistry, biology, physics, and computer science to develop unique solutions to common problems. Traditional introductory undergraduate laboratory curricula in the sciences often do not emphasize connections possible between the various disciplines. We designed an interdisciplinary, medically relevant, project intended to help students see connections between chemistry and biology. Second term organic chemistry laboratory students designed and synthesized potential polymer inhibitors or inducers of polyglutamine protein aggregation. The use of novel target compounds added the uncertainty of scientific research to the project. Biology laboratory students then tested the novel potential pharmaceuticals in Huntington's disease model assays, using in vitro polyglutamine peptide aggregation and in vivo lethality studies in Drosophila. Students read articles from the primary literature describing the system from both chemical and biological perspectives. Assessment revealed that students emerged from both courses with a deeper understanding of the interdisciplinary nature of biology and chemistry and a heightened interest in basic research. The design of this collaborative project for introductory biology and organic chemistry labs demonstrated how the local interests and expertise at a university can be drawn from to create an effective way to integrate these introductory courses. Rather than simply presenting a series of experiments to be replicated, we hope that our efforts will inspire other scientists to think about how some aspect of authentic work can be brought into their own courses, and we also welcome additional collaborations to extend the scope of the scientific exploration.


Assuntos
Biologia/educação , Química Orgânica/educação , Comportamento Cooperativo , Pesquisa/educação , Avaliação Educacional/métodos , Humanos , Laboratórios , Aprendizagem , Estudantes , Universidades
11.
J Orthop Trauma ; 29(1): e1-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24786734

RESUMO

OBJECTIVE: To compare the biomechanical stability under load-to-failure conditions of optimally placed fixed-angle volar locking plates versus suboptimally placed variable-angle volar locking plates in unstable, intraarticular distal radius fractures. METHODS: A Melone type 1 (AO 23-C3) fracture was created in 25 sawbone radii and plated with either a fixed-angle or variable-angle Synthes plate with identical profile. Four plate positions were tested: distal ulnar (DU, positioned distally to obtain subchondral support and ulnar to hold the lunate facet fragments), distal radial (DR, 3 mm radial to DU), proximal ulnar (PU, 3 mm proximal to DU), and proximal radial (PR, 3 mm proximal and 3 mm radial to DU). The specimens were loaded until failure as defined by a 2-mm displacement of any fracture fragment. The fixed-angle plates were tested in the DU position, whereas the variable-angle plates were tested in all 4 positions. RESULTS: The dorsal lunate fragment was the first to fail in every group followed by the radial styloid and volar lunate fragments, respectively. Load-to-failure, from greatest to least, occurred at the DR (278 ± 56 N), PR (277 ± 68 N), DU fixed-angle (277 ± 68 N), DU variable-angle (236 ± 31 N), and PU (202 ± 75 N) positions, respectively. Rigidity was calculated using the slope of the dorsal lunate force-displacement curve before failure (at loads 100-150 N). Rigidity was greatest at the PU position (126 ± 60 N/mm) followed by PR (125 ± 30 N/mm), DU fixed-angle (125 ± 25 N/mm), DR (122 ± 66 N/mm), and DU variable-angle (101 ± 35) positions, respectively. Univariate analysis of rigidity and load-to-failure was not significantly different between groups. CONCLUSIONS: In this experimental model, variable-angle screws provided a leeway of 3 mm in both the sagittal and coronal directions without sacrificing construct strength, which may considerably facilitate fixation of these difficult fractures.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas Intra-Articulares/cirurgia , Instabilidade Articular/cirurgia , Fraturas do Rádio/cirurgia , Fenômenos Biomecânicos , Humanos , Fraturas Intra-Articulares/fisiopatologia , Instabilidade Articular/fisiopatologia , Modelos Anatômicos , Fraturas do Rádio/fisiopatologia
12.
PLoS Genet ; 10(12): e1004813, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25474312

RESUMO

Epigenetic marks such as cytosine methylation are important determinants of cellular and whole-body phenotypes. However, the extent of, and reasons for inter-individual differences in cytosine methylation, and their association with phenotypic variation are poorly characterised. Here we present the first genome-wide study of cytosine methylation at single-nucleotide resolution in an animal model of human disease. We used whole-genome bisulfite sequencing in the spontaneously hypertensive rat (SHR), a model of cardiovascular disease, and the Brown Norway (BN) control strain, to define the genetic architecture of cytosine methylation in the mammalian heart and to test for association between methylation and pathophysiological phenotypes. Analysis of 10.6 million CpG dinucleotides identified 77,088 CpGs that were differentially methylated between the strains. In F1 hybrids we found 38,152 CpGs showing allele-specific methylation and 145 regions with parent-of-origin effects on methylation. Cis-linkage explained almost 60% of inter-strain variation in methylation at a subset of loci tested for linkage in a panel of recombinant inbred (RI) strains. Methylation analysis in isolated cardiomyocytes showed that in the majority of cases methylation differences in cardiomyocytes and non-cardiomyocytes were strain-dependent, confirming a strong genetic component for cytosine methylation. We observed preferential nucleotide usage associated with increased and decreased methylation that is remarkably conserved across species, suggesting a common mechanism for germline control of inter-individual variation in CpG methylation. In the RI strain panel, we found significant correlation of CpG methylation and levels of serum chromogranin B (CgB), a proposed biomarker of heart failure, which is evidence for a link between germline DNA sequence variation, CpG methylation differences and pathophysiological phenotypes in the SHR strain. Together, these results will stimulate further investigation of the molecular basis of locally regulated variation in CpG methylation and provide a starting point for understanding the relationship between the genetic control of CpG methylation and disease phenotypes.


Assuntos
Doenças Cardiovasculares/genética , Metilação de DNA , Genoma , Miocárdio/metabolismo , Animais , Sequência de Bases , Doenças Cardiovasculares/patologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Polimorfismo de Nucleotídeo Único , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos SHR , Análise de Sequência de DNA/métodos
13.
Langmuir ; 30(12): 3373-80, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24635125

RESUMO

Poly(tetrafluoroethylene) (PTFE) latex particles have been analyzed and sorted according to size using asymmetric flow field flow fractionation (AF4) coupled with multiple-angle light scattering (MALS). Characterization of fractions by regular and depolarized dynamic light scattering confirmed that smaller particles elute prior to larger ones, as expected for field flow fractionation. The measured radii of the optically and geometrically anisotropic particles are consistent with those determined from transmission electron microscopy (TEM). A certain amount of heterogeneity remains in the fractions, but their uniformity for use as diffusion probes is improved. Full characterization of PTFE colloids will require a difficult assessment of the distribution, even within fractions, of the optical anisotropy. A general method to obtain number versus size distributions is presented. This approach is valid even when an online concentration detector is not available or ineffective. The procedure is adaptable to particles of almost any regular shape.

14.
J Orthop Trauma ; 28(8): 470-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24121982

RESUMO

OBJECTIVE: To determine the biomechanical properties of plating options for distal ulna fractures. METHODS: Fourth-generation ulna artificial bones were osteotomized and fixed with 4 different constructs: 2 locking compression plates (a straight 2.7-mm plate and a 2.4-mm T-plate) with both nonlocking and locking screws. The artificial bones underwent nondestructive tests to determine construct stiffness in flexion/extension and lateral bending. The final testing consisted of cyclical loading in axial torsion until implant failure. RESULTS: The straight plate fixation construct was significantly stiffer than the T-plate construct for both flexion/extension bending (P < 0.001) and radial/ulnar bending (P < 0.05). Nonlocking screws provided significantly stiffer fixation in flexion bending than locking screws (P < 0.05); however, no difference was found in extension bending. Conversely, locking screws were significantly stiffer in radial/ulnar bending than the nonlocking screws (P < 0.05). Failure under torsional cyclical loading was significantly different among constructs. The straight plate with nonlocking construct withstood the most half-cycles. The mechanisms of failure were unique to each type of fixation. CONCLUSIONS: These results do not show any clear biomechanical advantage of locked plating for fractures of the distal ulna. The increased stiffness associated with locked plating likely contributes to earlier and more pronounced failure mechanisms under repetitive axial torsion.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas da Ulna/cirurgia , Fenômenos Biomecânicos , Humanos , Modelos Anatômicos , Fraturas da Ulna/fisiopatologia
15.
Dimens Crit Care Nurs ; 32(5): 262-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23933646

RESUMO

The purpose of this study was to evaluate the differences between automated and manual blood pressure results in patients with atrial fibrillation. Data collection took place on 3 telemetry units at a 519-bed community hospital. Findings indicate that there are statistically significant differences between automated and manual blood pressures in this patient population; however, the results are not clinically significant.


Assuntos
Fibrilação Atrial/fisiopatologia , Determinação da Pressão Arterial/instrumentação , Determinação da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Telemetria , Adulto , Idoso , Idoso de 80 Anos ou mais , Diástole/fisiologia , Feminino , Hospitais Comunitários , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Estudos de Amostragem , Esfigmomanômetros , Sístole/fisiologia
16.
Curr Biol ; 22(19): 1765-73, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22885065

RESUMO

BACKGROUND: The p53, Rb, and Ras/PI3K pathways are implicated in the development of the majority of human cancers. A number of studies have established that these pathways cooperate at the level of the cell cycle leading to loss of normal proliferative controls. Here we have investigated how these signals influence a second critical component of tumor formation-cell growth. RESULTS: We find that oncogenic Ras is sufficient to drive growth via the canonical growth pathway, PI3K-AKT-TOR; however, it does so relatively weakly and p53 loss does not drive cell growth at all. Importantly, we identify a novel role for the Rb family of tumor suppressors in directing cell growth via a signaling pathway distinct from PI3K-AKT-TOR and via an E2F-independent mechanism. However, we find that strong, sustained growth requires Rb loss together with Ras signaling, identifying an additional mechanism by which these oncogenic pathways cooperate and a critical role for Ras in preserving the uptake of extracellular nutrients required for biogenesis. CONCLUSIONS: We have identified a new role for the Rb family in cell biogenesis and show that, as for other processes associated with tumor development, oncogenic cell growth is dependent on cooperating oncogenes.


Assuntos
Proteína do Retinoblastoma/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patologia , Proteínas ras/metabolismo , Animais , Ciclo Celular , Proliferação de Células , Células Cultivadas , Fatores de Transcrição E2F/genética , Fatores de Transcrição E2F/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Proteína do Retinoblastoma/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas ras/genética
17.
Neuron ; 73(4): 729-42, 2012 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-22365547

RESUMO

Following damage to peripheral nerves, a remarkable process of clearance and regeneration takes place. Axons downstream of the injury degenerate, while the nerve is remodeled to direct axonal regrowth. Schwann cells are important for this regenerative process. "Sensing" damaged axons, they dedifferentiate to a progenitor-like state, in which they aid nerve regeneration. Here, we demonstrate that activation of an inducible Raf-kinase transgene in myelinated Schwann cells is sufficient to control this plasticity by inducing severe demyelination in the absence of axonal damage, with the period of demyelination/ataxia determined by the duration of Raf activation. Remarkably, activation of Raf-kinase also induces much of the inflammatory response important for nerve repair, including breakdown of the blood-nerve barrier and the influx of inflammatory cells. This reversible in vivo model identifies a central role for ERK signaling in Schwann cells in orchestrating nerve repair and is a powerful system for studying peripheral neuropathies and cancer.


Assuntos
Sistema de Sinalização das MAP Quinases/fisiologia , Regeneração Nervosa/genética , Traumatismos dos Nervos Periféricos/fisiopatologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Células de Schwann/fisiologia , Animais , Animais Recém-Nascidos , Benzamidas/farmacologia , Movimento Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Citocinas/metabolismo , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Antagonistas de Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Leucócitos/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Mastócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Bainha de Mielina/genética , Bainha de Mielina/metabolismo , Regeneração Nervosa/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/patologia , Traumatismos dos Nervos Periféricos/patologia , Proteínas Proto-Oncogênicas c-raf/genética , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , Receptor de Fator de Crescimento Neural/genética , Receptor de Fator de Crescimento Neural/metabolismo , Receptores de Estrogênio/genética , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/genética , Células de Schwann/ultraestrutura , Linfócitos T/metabolismo , Linfócitos T/patologia , Tamoxifeno/farmacologia , Fatores de Tempo
18.
Cardiovasc Res ; 92(2): 287-95, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21730037

RESUMO

AIMS: Elastin is the primary component of elastic fibres in arteries, which contribute significantly to the structural integrity of the wall. Fibrillin-1 is a microfibrillar glycoprotein that appears to stabilize elastic fibres mechanically and thereby to delay a fatigue-induced loss of function due to long-term repetitive loading. Whereas prior studies have addressed some aspects of ageing-related changes in the overall mechanical properties of arteries in mouse models of Marfan syndrome, we sought to assess for the first time the load-carrying capability of the elastic fibres early in maturity, prior to the development of ageing-related effects, dilatation, or dissection. METHODS AND RESULTS: We used elastase to degrade elastin in common carotid arteries excised, at 7-9 weeks of age, from a mouse model (mgR/mgR) of Marfan syndrome that expresses fibrillin-1 at 15-25% of normal levels. In vitro biaxial mechanical tests performed before and after exposure to elastase suggested that the elastic fibres exhibited a nearly normal load-bearing capability. Observations from nonlinear optical microscopy suggested further that competent elastic fibres not only contribute to load-bearing, they also increase the undulation of collagen fibres, which endows the normal arterial wall with a more compliant response to pressurization. CONCLUSION: These findings support the hypothesis that it is an accelerated fatigue-induced damage to or protease-related degradation of initially competent elastic fibres that render arteries in Marfan syndrome increasingly susceptible to dilatation, dissection, and rupture.


Assuntos
Artéria Carótida Primitiva/metabolismo , Tecido Elástico/metabolismo , Elastina/metabolismo , Síndrome de Marfan/metabolismo , Proteínas dos Microfilamentos/deficiência , Fatores Etários , Animais , Fenômenos Biomecânicos , Artéria Carótida Primitiva/patologia , Modelos Animais de Doenças , Progressão da Doença , Tecido Elástico/patologia , Fibrilina-1 , Fibrilinas , Masculino , Síndrome de Marfan/genética , Síndrome de Marfan/patologia , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Elastase Pancreática/metabolismo
19.
J Cataract Refract Surg ; 37(5): 853-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21511153

RESUMO

PURPOSE: To evaluate and compare patient-reported visual function, spectacle independence, and quality of life before and after cataract surgery with bilateral diffractive multifocal or monofocal intraocular lens (IOL) implantation. SETTING: Department of Ophthalmology, Henry Ford Health System, Taylor Branch, Detroit, Michigan, USA. DESIGN: Prospective cohort study. METHODS: This study evaluated consecutive cataract patients having bilateral implantation of Acrysof Restor SN60D3 multifocal IOLs or monofocal Acrysof SN60WF IOLs, the latter as monovision, between July 2007 and June 2009. Parameters analyzed 3 months postoperatively included binocular uncorrected distance, intermediate, and near visual acuities; stereo vision; spectacle independence; subjective visual symptoms; and patient satisfaction. Preoperative and postoperative quality of life was assessed with the National Eye Institute Visual Function Questionnaire-25(NEI VFQ-25). RESULTS: The multifocal group comprised 21 patients and the monovision group, 22 patients. Binocular uncorrected visual acuity at distance and near at 3 months was significantly better than preoperatively in both groups. In both groups, there was an improvement in all ocular and visual-related NEI VFQ-25 responses postoperatively. CONCLUSION: Bilateral multifocal IOLs and conventional monofocal IOL pseudophakic monovision significantly improved spectacle independence and visual quality-of-life measures.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares , Facoemulsificação , Pseudofacia/fisiopatologia , Acuidade Visual/fisiologia , Atividades Cotidianas , Idoso , Estudos de Coortes , Óculos/estatística & dados numéricos , Feminino , Humanos , Masculino , Estudos Prospectivos , Desenho de Prótese , Qualidade de Vida , Refração Ocular/fisiologia , Perfil de Impacto da Doença , Visão Binocular/fisiologia
20.
CBE Life Sci Educ ; 10(1): 18-24, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21364097

RESUMO

In introductory laboratory courses, many universities are turning from traditional laboratories with predictable outcomes to inquiry-inspired, project-based laboratory curricula. In these labs, students are allowed to design at least some portion of their own experiment and interpret new, undiscovered data. We have redesigned the introductory biology laboratory course at Brandeis University into a semester-long project-based laboratory that emphasizes concepts and contains an element of scientific inquiry. In this laboratory, students perform a site-directed mutagenesis experiment on the gene encoding human γD crystallin, a human eye lens protein implicated in cataracts, and assess the stability of their newly created protein with respect to wild-type crystallin. This laboratory utilizes basic techniques in molecular biology to emphasize the importance of connections between DNA and protein. This project lab has helped engage students in their own learning, has improved students' skills in critical thinking and analysis, and has promoted interest in basic research in biology.


Assuntos
Currículo , Laboratórios , Biologia Molecular/educação , Proteínas/química , Proteínas/metabolismo , Coleta de Dados , Humanos , Aprendizagem , Relação Estrutura-Atividade
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