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1.
J Synchrotron Radiat ; 28(Pt 6): 1935-1947, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738949

RESUMO

NanoMAX is the first hard X-ray nanoprobe beamline at the MAX IV laboratory. It utilizes the unique properties of the world's first operational multi-bend achromat storage ring to provide an intense and coherent focused beam for experiments with several methods. In this paper we present the beamline optics design in detail, show the performance figures, and give an overview of the surrounding infrastructure and the operational diffraction endstation.

2.
Front Psychol ; 11: 570694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162912

RESUMO

Research on human caused sound has shown a wide range of effects in outdoor environments as well as laboratory simulations of those environments. Aircraft noise, ground traffic, and human voices have all been shown to lower scenic evaluation ratings and influence individual reports of affective state. However, previous research has relied entirely on pre-post measures of affect and psychological state rather than more momentary assessments. The current project utilized a time series of 15 measurements of overall mood and relaxation collected during a 30-min period during which participants (N = 229) were exposed to randomized volume levels of natural sounds, natural sounds with aircraft noise, natural sounds with ground traffic, or natural sounds with human voices added. Results supported previous findings with significant sound type X volume interactions showing differing rates of decline for both outcomes. Natural sounds did not relate to the diminishing effects observed for the three anthropogenic sound conditions.

3.
Int J Psychiatry Med ; 55(5): 376-383, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32883136

RESUMO

BACKGROUND: The American Council of Graduate Medical Education (ACGME) guidelines for scholarly activities by family medicine residents require at least one activity per resident and encourage conference presentations. Meeting these guidelines has traditionally been challenging due to a multitude of factors from lack of time to limited administrative support. Studies have shown that resident participation in research was associated with higher levels of satisfaction with training. We aimed to develop and evaluate the effectiveness of a dedicated research curriculum in achieving ACGME goals for our residents. METHODS: We performed a need assessment that identified strengths and obstacles related to research which then guided the actions taken to build the curriculum. Revised curricular elements included a research focused lecture series, a restructured journal club, financial support for presentations and project expenses, a specific timeline for project completion, and the development of a regional research day involving multiple family medicine programs. Dedicated research time was built into the resident schedule and presentations at local, regional and national conferences were encouraged and supported. RESULTS: Following implementation of the curriculum there was a marked increase in the number of scholarly projects performed by residents. Prior to implementation there had only been one presentation at a national conference in the previous five years. This increased to an average of four presentations per year in the following five year period. On a regional scale, the initial success of the local research day led to a continued expansion and now includes six family medicine programs. CONCLUSION: Implementation of a dedicated multifaceted research curriculum significantly increased the participation of our residents in scholarly activities and led to a near five-fold increase in presentations at regional and national levels. Additionally, resident satisfaction in scholarly activities increased and a far greater number of graduating residents went on to complete fellowships.


Assuntos
Pesquisa Biomédica/educação , Currículo , Medicina de Família e Comunidade/educação , Internato e Residência , Educação de Pós-Graduação em Medicina , Bolsas de Estudo , Humanos , Determinação de Necessidades de Cuidados de Saúde , Apoio à Pesquisa como Assunto , Fatores de Tempo
4.
Health Care Manag (Frederick) ; 36(4): 320-325, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28953069

RESUMO

E-scripts have been used as part of computerized provider order entry implementation for several years now, particularly with the passage of the American Recovery and Reinvestment Act, Meaningful Use, the Health Information Portability and Accountability Act, the Health Information Technology for Economic and Clinical Health Act, and other laws and regulations. This case study seeks to focus on 2 specific aspects of the effect of increasing electronic technology within health care: e-prescriptions and cell phones or smartphones.


Assuntos
Telefone Celular , Segurança Computacional/normas , Registros Eletrônicos de Saúde/estatística & dados numéricos , Informática Médica/normas , Sistemas de Registro de Ordens Médicas/estatística & dados numéricos , Atenção à Saúde , Health Insurance Portability and Accountability Act , Humanos , Estudos de Casos Organizacionais , Estados Unidos
5.
Ulster Med J ; 84(3): 164-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26668418

RESUMO

AIMS AND METHOD: To assess the need for the provision of low secure care in Northern Ireland. A survey of the providers of healthcare in Northern Ireland was conducted using a study tool based on Royal College of Psychiatrists Low Secure Network Standards admission criteria. RESULTS: A total of 105 patients were assessed as needing low secure care including 93 patients currently admitted to hospital in the region and 12 patients admitted to hospital outside of the region. CLINICAL IMPLICATIONS: The results of this study are similar to previous estimates of need for the provision of low secure care in the UK. The results provide information likely to be of assistance in the commissioning of low secure services. DECLARATION OF INTEREST: None.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Transtornos Mentais/reabilitação , Serviços de Saúde Mental/provisão & distribuição , Medidas de Segurança , Adulto , Feminino , Instalações de Saúde/provisão & distribuição , Humanos , Masculino , Determinação de Necessidades de Cuidados de Saúde , Irlanda do Norte , Adulto Jovem
6.
J Grad Med Educ ; 7(1): 59-64, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26217424

RESUMO

BACKGROUND: Despite well-established negative consequences, high rates of substance use and related disorders continue to be reported. Physicians in training are not immune from this, or the associated risks to their health and careers, while impaired physicians are a threat to patient safety. OBJECTIVE: We surveyed family medicine residency programs' practices relating to drug testing of medical students and incoming residents. The survey asked about the extent to which residency programs are confronted with trainees testing positive for prohibited substances, and how they respond. METHODS: The survey was sent to the directors of family medicine residency programs. A total of 205 directors (47.2%) completed the survey. RESULTS: A majority of the responding programs required drug testing for incoming residents (143, 68.9%). Most programs did not require testing of medical students (161, 81.7%). Few programs reported positive drug tests among incoming residents (9, 6.5%), and there was only 1 reported instance of a positive result among medical students (1, 3.3%). Respondents reported a range of responses to positive results, with few reporting that they would keep open training spots or offer supportive services for a medical student who tested positive. CONCLUSIONS: Changing laws legalizing certain drugs may require corresponding changes in the focus on drug testing and associated issues in medical training; however, many residency program directors were not aware of their institution's current policies. Programs will need to reexamine drug testing policies as new generations of physicians, growing up under altered legal circumstances concerning drug use, progress to clinical training.


Assuntos
Medicina de Família e Comunidade/educação , Internato e Residência , Estudantes de Medicina , Detecção do Abuso de Substâncias , Adulto , Feminino , Humanos , Masculino , Seleção de Pessoal , Inquéritos e Questionários , Estados Unidos
7.
Health Estate ; 65(8): 71-4, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21961395

RESUMO

Creating a new hospital that proves itself to be sustainable on a greenfield site is quite a challenge. Paul Bell, director at Ryder Architecture, describes how the St Andrews Community Hospital and Health Centre has been delivered to achieve just that for NHS Fife.


Assuntos
Conservação dos Recursos Naturais , Arquitetura Hospitalar , Hospitais Comunitários , Estudos de Casos Organizacionais , Reino Unido
8.
Artigo em Inglês | MEDLINE | ID: mdl-21796264

RESUMO

In this study, we report on a qualitative method known as the Delphi method, used in the first part of a research study for improving the accuracy and reliability of ICD-9-CM coding. A panel of independent coding experts interacted methodically to determine that the three criteria to identify a problematic ICD-9-CM subcategory for further study were cost, volume, and level of coding confusion caused. The Medicare Provider Analysis and Review (MEDPAR) 2007 fiscal year data set as well as suggestions from the experts were used to identify coding subcategories based on cost and volume data. Next, the panelists performed two rounds of independent ranking before identifying Excisional Debridement as the subcategory that causes the most confusion among coders. As a result, they recommended it for further study aimed at improving coding accuracy and variation. This framework can be adopted at different levels for similar studies in need of a schema for determining problematic subcategories of code sets.


Assuntos
Desbridamento/métodos , Técnica Delfos , Classificação Internacional de Doenças/classificação , Codificação Clínica/métodos , Desbridamento/classificação , Prova Pericial , Humanos , Pesquisa Qualitativa , Estados Unidos
9.
Postgrad Med ; 121(5): 140-4, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19820282

RESUMO

Recognition of the prevalence of mood disorders and increased availability of medication options have led to calls for treating bipolar disorders in the primary care setting. Second-generation antipsychotic medications (SGAs) were initially lauded for treating bipolar disorders because of their efficacy and perceived safety relative to first-generation antipsychotic medications. Metabolic syndrome is a constellation of risk factors for cardiovascular disease and type 2 diabetes mellitus, which may emerge when treating bipolar disorders with SGAs. We conducted a search of the research literature examining the association between different SGAs and metabolic syndrome. Based on our review, we offer guidelines for monitoring patient status regarding metabolic syndrome and for providing interventions to promote healthy diet and exercise.


Assuntos
Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/epidemiologia , Atenção Primária à Saúde/métodos , Adulto , Doença Crônica , Comorbidade , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Humanos , Masculino , Adesão à Medicação , Síndrome Metabólica/tratamento farmacológico , Prevalência , Gestão de Riscos
10.
J Gerontol Soc Work ; 52(2): 89-104, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19197633

RESUMO

Alzheimer's disease can be particularly devastating to those who are caring for their loved one with the condition. There have been recent calls for the tailoring of caregiving interventions to examine outcome differences between groups of caregivers and the reporting of effectiveness via longitudinal and specific outcomes. The purpose of this study was to examine 3 interventions (psychoeducational training, a respite voucher-type grant, or their combination) while looking for possible group differences. A total of 367 caregivers participated in the study. Participants completed surveys and questionnaires before the intervention and at a 6-month follow-up. Positive outcomes were found, including lower depression scores, increased support service use, and increased support group usage. Possible effectiveness of the 3 types of interventions and variation among caregiver characteristics are discussed along with implications for future research.


Assuntos
Doença de Alzheimer , Cuidadores/psicologia , Educação em Saúde/organização & administração , Cuidados Intermitentes/psicologia , Estresse Psicológico/psicologia , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Grupos de Autoajuda , Fatores Sexuais , Apoio Social
11.
Health Care Manag (Frederick) ; 27(1): 58-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18510145

RESUMO

Web 2.0 is one of the latest buzzwords for an assortment of emerging technologies on the Web. Health care managers need to know the benefits and drawbacks of these technologies before integrating them into organizational operations. In this article, we first illustrate the differences in health care management style and workflow between the Web 1.0 and Web 2.0 technologies. After defining and explaining some of the representative technologies, we discuss the benefits of Web 2.0 in general and the reasons why a health care manager should know these trends. And lastly, we list some caveats that a health care manager should know before fully embracing the technologies. The keys are to align the technologies with the culture and workflow of the organization and have a clear policy on their usages.


Assuntos
Administradores de Instituições de Saúde , Internet/tendências , Humanos , Internet/organização & administração , Estados Unidos
12.
Biochemistry ; 46(45): 12930-44, 2007 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-17935306

RESUMO

Nonviral gene delivery vectors now show good therapeutic potential: however, detailed characterization of the composition and macromolecular organization of such particles remains a challenge. This paper describes experiments to elucidate the structure of a ternary, targeted, lipopolyplex synthetic vector, the LID complex. This consists of a lipid component, Lipofectin (L) (1:1 DOTMA:DOPE), plasmid DNA (D), and a dual-function, cationic peptide component (I) containing DNA condensation and integrin-targeting sequences. Fluorophore-labeled lipid, peptide, and DNA components were used to formulate the vector, and the stoichiometry of the particles was established by fluorescence correlation spectroscopy (FCS). The size of the complex was measured by FCS, and the sizes of LID, L, LD, and ID complexes were measured by dynamic light scattering (DLS). Fluorescence quenching experiments and freeze-fracture electron microscopy were then used to demonstrate the arrangement of the lipid, peptide, and DNA components within the complex. These experiments showed that the cationic portion of the peptide, I, interacts with the plasmid DNA, resulting in a tightly condensed DNA-peptide inner core; this is surrounded by a disordered lipid layer, from which the integrin-targeting sequence of the peptide partially protrudes.


Assuntos
Vetores Genéticos , Integrinas , Fenômenos Biofísicos , Biofísica , DNA/química , Difusão , Técnica de Fratura por Congelamento , Luz , Lipossomos/síntese química , Microscopia Eletrônica , Fosfatidiletanolaminas/química , Compostos de Amônio Quaternário/química , Espalhamento de Radiação , Espectrometria de Fluorescência
13.
Br J Soc Psychol ; 46(Pt 1): 19-42, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17355717

RESUMO

The authors hypothesized that (1) attraction toward a stranger based on attitudinal similarity is automatic, but cognitive evaluation of the stranger's quality before the measurement of attraction can make attraction nonautomatic or controlled; (2) personal evaluations from the stranger activate automatic attraction and cognitive evaluation; (3) controlled attraction from attitudes and automatic attraction and cognitive evaluation from personal evaluations engender reverse-causal effects (i.e. they mediate each other); and (4) attraction and cognitive evaluation are distinct constructs. Attitudinal similarity between the participant and the stranger or personal evaluations of the former by the latter were varied in Experiment 1 (N=96), and were crossed with each other in Experiment 2 (N=240). Orders of response measurement were either cognitive evaluation followed by attraction or attraction followed by cognitive evaluation. Results confirmed the hypotheses. Implications of the findings are discussed.


Assuntos
Atitude , Cognição , Relações Interpessoais , Adolescente , Adulto , Pesquisa Comportamental , Feminino , Humanos , Julgamento , Masculino , Singapura
14.
J Biomed Opt ; 11(6): 064008, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17212531

RESUMO

Transverse excited atmospheric pressure (TEA) CO(2) lasers tuned to the strong mineral absorption of hydroxyapatite near lambda=9 microm are well suited for the efficient ablation of dental hard tissues if the laser pulse is stretched to greater than 5 to 10 micros to avoid plasma shielding phenomena. Such CO(2) lasers are capable of operating at high repetition rates for the rapid removal of dental hard tissues. The purpose of this study was to test the hypothesis that stretched lambda=9.3-microA CO(2) laser pulses can produce lateral incisions in enamel, dentin, and alveolar bone for dental restorations and implants at repetition rates as high as 400 Hz without peripheral thermal damage. The single pulse ablation rates through enamel, dentin, and bone were determined for incident fluence ranging from (1 to 160 J/m(2)) for laser pulses from 5 to 18 mus in duration. Lateral incisions were produced in hard tissue samples using a computer-controlled scanning stage and water spray, and the crater morphology and chemical composition were measured using optical microscopy and high-resolution synchrotron radiation infrared spectromicroscopy. The residual energy remaining in tooth samples was measured to be 30 to 40% for enamel and 20 to 30% for dentin without water cooling, under optimum irradiation intensities, significantly lower than for longer CO(2) laser pulses. The transmission through 2-m length 300-, 500-, 750-, and 1000-microm silica hollow waveguides was measured and 80% transmission was achieved with 40 mJ per pulse. These results suggest that high repetition rate TEA CO(2) laser systems operating at lambda=9.3 microm with pulse durations of 10 to 20 micros are well suited for dental applications.


Assuntos
Esmalte Dentário/cirurgia , Dentina/cirurgia , Terapia a Laser/instrumentação , Terapia a Laser/métodos , Dente Molar/cirurgia , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Animais , Pressão Atmosférica , Dióxido de Carbono , Esmalte Dentário/citologia , Dentina/citologia , Humanos , Técnicas In Vitro , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Dente Molar/citologia , Suínos
15.
Perspect Health Inf Manag ; 3: 7, 2006 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-18066365

RESUMO

This study examined the effects of self-regulated learning (SRL) and epistemological beliefs (EB) on individual learner levels of academic achievement in Web-based learning environments while holding constant the effect of computer self-efficacy, reason for taking an online course, and prior college academic achievement. The study constituents included 201 undergraduate students enrolled in a variety of asynchronous Web-based courses at a university in the southeastern United States. Data was collected via a Web-based questionnaire and subjected to the following analyses: separate exploratory factor analyses of the self-regulated learning and the epistemological beliefs question items, correlations between the independent variables and the dependent variable, and linear regression of final course grades with all the variables in the model. Analysis of the data revealed that three independent variables (GPA, Expectancy, and GPA_Exp) were significant predictors in the model of learning achievement in asynchronous online courses. Discussion of the study's predictive model follows.

16.
Rural Remote Health ; 5(3): 466, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16162076

RESUMO

OBJECTIVE: Alzheimer's disease can be particularly devastating to those living in rural communities where caregivers are typically older and access to supportive services is more limited than in urban areas. The purpose of this study was to examine an ongoing intervention that targets the needs of rural dementia caregivers by providing appropriate education, training, and access to services. METHOD: A total of 54 rural and 42 urban caregivers participated in the Savvy Caregiver Program in their local communities, with training of 1 week, 2 week, or 3 week sessions by staff of the Alzheimer's Association, Colorado Chapter. Participants completed multiple surveys and questionnaires both before the training and at a 6 month follow-up phone interview. RESULTS: Positive outcomes of the training were found at 6 month follow up for both the rural and urban group, including reported use of the printed manual and CD-ROM. Caregivers reported structuring meaningful activities for the person with dementia. Improved depression scores were found for the rural group, and overall support group use increased. DISCUSSION: The outcomes suggest that targeting rural communities for caregiver training can result in more use of supportive services, effective caregiving strategies, and improved caregiver wellbeing, even in low density population areas where supportive services are more difficult to access.


Assuntos
Doença de Alzheimer/enfermagem , Cuidadores/educação , Desenvolvimento de Programas , Serviços de Saúde Rural/organização & administração , Idoso , Cuidadores/psicologia , Cuidadores/estatística & dados numéricos , Colorado , Comportamento do Consumidor/estatística & dados numéricos , Depressão/diagnóstico , Depressão/prevenção & controle , Feminino , Seguimentos , Pesquisas sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Grupos de Autoajuda/estatística & dados numéricos
17.
J Pers Soc Psychol ; 89(1): 71-3, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16060745

RESUMO

B. J. Bushman, M. C. Wang, and C. A. Anderson argued that a reanalysis of E. G. Cohn and J. Rotton's Minneapolis data shows no inverted-U curvilinear relationship between temperature and aggression. Although B. J. Bushman et al.'s claim of no general inverted-U trend in the data might well be supported statistically, more careful examination of the subset of the data most likely to include the hottest temperatures in the study may offer at least some support for the inverted-U relationship. Aggregating data to describe a general trend minimizes the influence of outliers that may reflect alternative relationships, and such alternatives may be important practically and theoretically.


Assuntos
Agressão , Modelos Psicológicos , Temperatura , Violência , Temperatura Alta , Humanos , Modelos Lineares , Periodicidade
18.
J Drug Target ; 12(4): 185-93, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15506167

RESUMO

Human airway epithelial cell targeting peptides were identified by biopanning on 1HAEo-cells, a well characterised epithelial cell line. Bound phage were recovered after three rounds of binding, high stringency washing and elution, leading to the production of an enriched phage peptide population. DNA sequencing of 56 clones revealed 14 unique sequences. Subsequent binding analysis revealed that 13 of these peptides bound 1HAEo-cells with high affinity. Three peptides, SERSMNF, YGLPHKF and PSGAARA were represented at high frequency. Three clearly defined families of peptide were identified on the basis of sequence motifs including (R/K)SM, L(P/Q)HK and PSG(A/T)ARA. Two peptides, LPHKSMP and LQHKSMP contained two motifs. Further detailed sequence analysis by comparison of peptide sequences with the SWISSPROT protein database revealed that some of the peptides closely resembled the cell binding proteins of viral and bacterial pathogens including Herpes Simplex Virus, rotavirus, Mycoplasma pneumoniae and rhinovirus, the latter two being respiratory pathogens, as well as peptide YGLPHKF having similarity to a protein of unknown function from the respiratory pathogen Legionella pneumophila. Peptides were incorporated into gene delivery formulations with the cationic lipid Lipofectin and plasmid DNA and shown to confer a high degree of transfection efficiency and specificity in 1HAEo-cells. Improved transfection efficiency and specificity was also observed in human endothelial cells, fibroblasts and keratinocytes. Therefore, on the basis of clone frequency after biopanning, cell binding affinity, peptide sequence conservation and pathogenic similarity, we have identified 3 novel peptide families and 5 specific peptides that have the potential for gene transfer to respiratory epithelium in vivo as well as providing useful in vitro transfection reagents for primary human cell types of scientific and commercial interest.


Assuntos
Portadores de Fármacos/química , Células Epiteliais/metabolismo , Peptídeos/química , Sistema Respiratório/metabolismo , Transfecção , Sequência de Aminoácidos , Linhagem Celular , Portadores de Fármacos/metabolismo , Ensaio de Imunoadsorção Enzimática , Genes Reporter , Vetores Genéticos , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Humanos , Biblioteca de Peptídeos , Peptídeos/metabolismo , Fosfatidiletanolaminas , Ligação Proteica , Sistema Respiratório/citologia , Relação Estrutura-Atividade
19.
Angew Chem Int Ed Engl ; 42(13): 1448-57, 2003 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-12698476

RESUMO

The superior surfactant properties of cationic gemini surfactants are applied to the complex problem of introducing genes into cells. Of almost 250 new compounds tested, of some 20 different structural types, a majority showed very good transfection activity in vitro. The surfactant is shown to bind and compact DNA efficiently, and structural studies and calculations provide a working picture of the "lipoplex" formed. The lipoplex can penetrate the outer membranes of many cell types, to appear in the cytoplasm encapsulated within endosomes. Escape from the endosome--a key step for transfection--may be controlled by changes in the aggregation behavior of the lipoplex as the pH falls. The evidence suggests that DNA may be released from the lipoplex before entry into the nucleus, where the new gene can be expressed with high efficiency.


Assuntos
Terapia Genética/métodos , Lipossomos/química , Tensoativos/química , Transfecção/métodos , Relação Estrutura-Atividade
20.
J Am Chem Soc ; 125(6): 1551-8, 2003 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-12568615

RESUMO

The structure of the lipoplex formed from DNA and the sugar-based cationic gemini surfactant 1, which exhibits excellent transfection efficiency, has been investigated in the pH range 8.8-3.0 utilizing small-angle X-ray scattering (SAXS) and cryo-electron microscopy (cryo-TEM). Uniquely, three well-defined morphologies of the lipoplex were observed upon gradual acidification: a lamellar phase, a condensed lamellar phase, and an inverted hexagonal (H(II)) columnar phase. Using molecular modeling, we link the observed lipoplex morphologies and physical behavior to specific structural features in the individual surfactant, illuminating key factors in future surfactant design, viz., a spacer of six methylene groups, the presence of two nitrogens that can be protonated in the physiological pH range, two unsaturated alkyl tails, and hydrophilic sugar headgroups. Assuming that the mechanism of transfection by synthetic cationic surfactants involves endocytosis, we contend that the efficacy of gemini surfactant 1 as a gene delivery vehicle can be explained by the unprecedented observation of a pH-induced formation of the inverted hexagonal phase of the lipoplex in the endosomal pH range. This change in morphology leads to destabilization of the endosome through fusion of the lipoplex with the endosomal wall, resulting in release of DNA into the cytoplasm.


Assuntos
DNA/química , Endossomos/metabolismo , Tensoativos/química , Transfecção/métodos , Microscopia Crioeletrônica , DNA/genética , DNA/metabolismo , Concentração de Íons de Hidrogênio , Lipossomos/química , Modelos Moleculares , Espalhamento de Radiação , Tensoativos/farmacocinética , Raios X
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