Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Arch Womens Ment Health ; 22(5): 613-620, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30353272

RESUMO

Optimal maternal caregiving is critical for children's healthy development, yet quality of maternal caregiving may be influenced by a negative birth experience. We examined whether the birth experience was associated with maternal caregiving attitudes and behavior throughout the first year. We conducted secondary analysis of the Avon Longitudinal Study of Parents and Children birth cohort on perinatal data. The birth experience was assessed using self-report data on level of support in labor. Maternal caregiving variables were self-report maternal attitudes at one and eight postnatal months, and observed maternal behavior at 12 postnatal months. Data were analyzed using multivariable logistic regression models adjusting for critical covariates at one (N = 4389), eight (N = 4580), and 12 (N = 842) postnatal months. Feeling supported in labor was associated with a report of "immediately falling in love" with one's baby after birth, surveyed at 1 month (adjusted OR 1.41 [95% CI 1.20-1.65]), and with more positive parenting scores at 8 months (adjusted OR 1.56 [95% CI 1.36-1.79]), but not with more positive observed maternal behavior at 12 months. Additional risk factors were identified. Our findings suggest that we may be able to modify the risk of poor postnatal maternal caregiving by supporting women in labor and facilitating a positive birth experience.


Assuntos
Comportamento Materno/psicologia , Mães/psicologia , Parto/psicologia , Apoio Social , Adulto , Feminino , Humanos , Lactente , Estudos Longitudinais , Apego ao Objeto , Poder Familiar , Período Pós-Parto , Gravidez , Fatores de Risco
2.
Arch Womens Ment Health ; 19(2): 219-27, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26202722

RESUMO

We investigated associations between aspects of childbirth and elevated postpartum symptoms of depression and anxiety. We employed secondary analysis of perinatal data (N = 4657-4946) from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Multivariable logistic regression models (adjusted for covariates) examined predictors of elevated symptoms of postpartum depression and anxiety. Predictors included the following: type of delivery (normal physiological vs. interventive non-physiological), immediate postpartum complications, and maternal perception of the recent birth experience. The Edinburgh Postnatal Depression Scale assessed elevated symptoms of depression (score ≥ 13), and the Crown-Crisp Experiential Index assessed elevated symptoms of anxiety (score ≥ 9) at 2 and 8 months after delivery. A more negative perception of the recent birth experience was associated with elevated symptoms of anxiety at 2 months [odds ratio (OR) 1.52, 95 % confidence interval (CI) 1.25-1.85] and 8 months (OR 1.30, 95 % CI 1.06-1.60) postpartum but was not associated with elevated symptoms of depression at either time point. Type of delivery (physiological vs. non-physiological) and immediate postpartum complications were not associated with elevated symptoms of depression or anxiety. Our findings suggest that improving women's childbirth experience may decrease the likelihood of postpartum anxiety, but not postpartum depression.


Assuntos
Ansiedade/diagnóstico , Parto Obstétrico/psicologia , Depressão Pós-Parto/diagnóstico , Parto/psicologia , Complicações na Gravidez/psicologia , Adolescente , Adulto , Ansiedade/epidemiologia , Criança , Parto Obstétrico/métodos , Depressão Pós-Parto/epidemiologia , Feminino , Humanos , Modelos Logísticos , Período Pós-Parto , Gravidez , Complicações na Gravidez/epidemiologia , Prevalência , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Fatores de Risco , Inquéritos e Questionários , Reino Unido/epidemiologia
3.
Appetite ; 60(1): 231-238, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23092758

RESUMO

Food and beverage packaging has been identified as a contributing factor to malnutrition among elderly patients in hospitals. The focus of this research was to describe the types of food and beverage packaging used in NSW hospitals, determine the 'problematic' packaging from the users' perspective, investigate the effect of hand strength on the ability to open the packaging and to survey users' (patients and staff) views on the 'accessibility' of the packaging. The study was conducted in the Illawarra region of NSW, Australia. Participants (140 mostly elderly inpatients and 64 staff members) were recruited from four local public hospitals. Data were collected using interviews, questionnaires, observations and grip strength testing. Several food and beverage packages were found difficult to open by at least 40% of patients. These included milk and juices (52%), cereal (49%), condiments (46%), tetra packs (40%) and water bottles (40%). The difficulties were attributed to 'fiddly' packaging, hand strength and vision; however, only tetra packs demonstrated a relationship between time taken to open and hand strength, suggesting other aspects of hand function may be more important than strength when opening food and beverage packages.


Assuntos
Embalagem de Alimentos/métodos , Serviço Hospitalar de Nutrição , Força da Mão/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Austrália , Bebidas , Fenômenos Fisiológicos da Nutrição do Idoso , Feminino , Humanos , Pacientes Internados , Masculino , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Leite , Inquéritos e Questionários
4.
Prog Biophys Mol Biol ; 73(1): 1-49, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10781828

RESUMO

Raman optical activity (ROA) measures vibrational optical activity by means of a small difference in the intensity of Raman scattering from chiral molecules in right and left circularly polarized incident laser light. The ROA spectra of a wide range of biomolecules in aqueous solution can now be measured routinely. Because of its sensitivity to the chiral elements of biomolecular structure, ROA provides new information about solution structure and dynamics complementary to that supplied by conventional spectroscopic techniques. This article provides a brief introduction to the theory and practice of ROA spectroscopy followed by a review of recent ROA results on polypeptides, proteins, carbohydrates, nucleic acids and viruses which illustrate how new insight into current problems of structure, folding and function may be obtained from ROA studies.


Assuntos
Análise Espectral Raman/métodos , Animais , Carboidratos/química , Humanos , Ácidos Nucleicos/química , Peptídeos/química , Proteínas/química , Vírus/química
5.
J Mol Biol ; 290(1): 1-7, 1999 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-10388553

RESUMO

We report the first observations of vibrational Raman optical activity (ROA) on intact viruses. Specifically, ROA spectra of the filamentous bacteriophages Pf1, M13 and IKe in aqueous solution were measured in the range approximately 600-1800 cm-1. On account of its ability to probe directly the chiral elements of biomolecular structure, ROA has provided a new perspective on the solution structures of these well-studied systems. The ROA spectra of all three are dominated by signatures of helical elements in the major coat proteins, as expected from pre-existing data. The helical elements generate strong sharp positive ROA bands at approximately 1300 and 1342 cm-1in H2O solution, but in2H2O solution the approximately 1342 cm-1bands disappear completely. The spectra are similar to those of polypeptides under conditions that produce alpha-helical conformations. Our present results, together with results from other studies, suggest that the positive approximately 1342 cm-1ROA bands are generated by a highly hydrated form of alpha-helix, and that the positive approximately 1300 cm-1bands originate in alpha-helix in a more hydrophobic environment. The presence of significant amounts of highly hydrated helical sequences accords with the known flexibility of these viruses. Differences of spectral detail for Pf1, M13 and IKe demonstrate that ROA is sensitive to subtle variations of conformation and hydration within the major coat proteins, with M13 and IKe possibly containing more non-helical structure than Pf1. The ROA spectra of Pf1 at temperatures above and below that at which a structural transition is known to occur (approximately 10 degrees C) reveal little difference in the protein conformation between the two forms, but there are indications of changes in DNA structure.


Assuntos
Bacteriófagos/genética , DNA Viral/química , Conformação de Ácido Nucleico , Sequência de Aminoácidos , Bacteriófagos/química , Capsídeo/química , Dados de Sequência Molecular , Análise Espectral Raman , Água/química
6.
Sci Prog ; 81 ( Pt 1): 17-34, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9567775

RESUMO

Determination of the solution structure and function of biomolecules such as proteins, carbohydrates and nucleic acids remains at the forefront of biomedical research. Thanks to recent developments in instrumentation, biomolecules can now be studied using Raman optical activity (ROA), a novel technique which measures vibrational optical activity in chiral molecules by means of a small difference in the intensity of Raman scattering in right- and left-circularly polarized incident laser light. This article reviews recent progress in the application of ROA to the determination of the solution structure and dynamics of proteins, carbohydrates and nucleic acids.


Assuntos
Configuração de Carboidratos , Conformação de Ácido Nucleico , Conformação Proteica , Análise Espectral Raman , Modelos Moleculares
7.
Otolaryngol Head Neck Surg ; 94(4): 504-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3086813

RESUMO

Electrocautery is used extensively in otolaryngology--head and neck surgery. Its commonplace use and excellent safety record may lull the surgeon from heeding the device's potential dangers. User error causes the majority of patient injuries. A thorough understanding of the electrophysical principles and hazards is essential for even the occasional user. Three cases of electrosurgical injury are reported to demonstrate problem areas in electrocautery usage. The basic electrophysical properties are described, and guidelines for prevention of injury to the patient are reviewed.


Assuntos
Queimaduras por Corrente Elétrica/etiologia , Eletrocoagulação/efeitos adversos , Otorrinolaringopatias/cirurgia , Adolescente , Adulto , Queimaduras por Corrente Elétrica/prevenção & controle , Eletrocoagulação/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Postura , Risco
8.
Otolaryngol Head Neck Surg ; 105(3): 376-81, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1945422

RESUMO

Sarcoidosis is a chronic, idiopathic granulomatous disease with frequent pulmonary, ocular, and lymphatic systemic manifestations. Central nervous system involvement is rare (1% to 5%), yet the most frequent presenting symptoms (48%) in patients with neurosarcoidosis are neurologic. Eighth cranial nerve abnormalities occur in 20% of these patients, typically in association with other cranial neuropathies or overt systemic disease. Isolated eighth nerve disease is very rare. We report two cases of neurosarcoidosis manifest as isolated, sudden onset sensorineural hearing loss, one of which had a cerebellopontine angle (CPA) granuloma that mimicked an acoustic neuroma. Both patients experienced marked steroid-induced hearing improvement that persisted after termination of therapy. Brainstem evoked response audiometry (BSER) abnormality persisted despite normalization of audiologic parameters. The implications for diagnosis and treatment of sarcoidosis-induced hearing loss are described. Neurosarcoidosis must be considered when evaluating patients with sudden hearing loss. Prompt steroid therapy offers hope for significant hearing recovery in these patients.


Assuntos
Encefalopatias/complicações , Perda Auditiva Neurossensorial/etiologia , Sarcoidose/complicações , Adulto , Audiometria , Doenças Cerebelares/complicações , Ângulo Cerebelopontino , Feminino , Granuloma/complicações , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Meningite Asséptica/complicações
9.
Int J Biol Macromol ; 16(5): 277-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7893631

RESUMO

This paper reports the first vibrational Raman optical activity (ROA) spectrum of a glycoprotein. The sample, orosomucoid (alpha 1-acid glycoprotein), shows ROA bands characteristic of a high beta-sheet content together with new bands which could be specific for the carbohydrate and its association with the protein. Our results suggest that ROA spectra of intact glycoproteins may contain information about both protein and carbohydrate conformation and the mutual influence on each other's stability and conformation.


Assuntos
Glicoproteínas/química , Análise Espectral Raman , Configuração de Carboidratos , Humanos , Orosomucoide/química , Conformação Proteica , Vibração
10.
Aviat Space Environ Med ; 66(1): 73-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7695557

RESUMO

Traumatic vertebral artery injuries are relatively rare. Until recently, insufficient neurodiagnostic technology and a lack of normative data for the population of USAF aviators prevented recommending flying waivers following such vascular injuries. We report the case of an aviator who experienced a traumatic right vertebral artery occlusion with distal embolization. Timely access to a state-of-the-art neurodiagnostic evaluation, which included time-of-flight magnetic resonance angiography (MRA), and standard contrast angiography, provided anatomic imaging at the time of injury and during the recuperative period. Sophisticated neurologic testing protocols at the Armstrong Laboratory's Aeromedical Clinical Sciences Division, Brooks Air Force Base, TX, assessed in-depth this individual's functional status. Consult Service evaluators then compared his performance data with current data in the Head Injury Study in Aviators (HISA) data base. MRA, in comparison with standard contrast angiography, demonstrated anatomic stability of his vascular and neurologic lesions. He demonstrated a functional capacity consistent with normal neurologic functioning in aviators which permitted recommending an occupational (flying) waiver. This case exemplified application of sophisticated ACS neurologic testing protocols to aeromedical evaluations and the use of MRA technology as a vascular screening tool during medical followup.


Assuntos
Arteriopatias Oclusivas/etiologia , Militares , Artéria Vertebral/lesões , Avaliação da Capacidade de Trabalho , Adulto , Medicina Aeroespacial , Arteriopatias Oclusivas/diagnóstico , Seguimentos , Nível de Saúde , Humanos , Angiografia por Ressonância Magnética , Masculino
11.
Aviat Space Environ Med ; 65(5 Suppl): A62-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8018081

RESUMO

Pursuit tracking eye movements were analyzed from selected patients with neurological injuries and compared to the responses of 20 normal subjects. The patients/subjects tracked a small spot of light moving sinusoidally in the horizontal plane at a frequency of 0.4 Hz and a peak-to-peak amplitude of 40 degrees. Eye-movement responses were separated into a smooth-pursuit component and a saccadic component. The smooth-pursuit component was analyzed by calculating the gain, phase, and asymmetry. The saccadic component was quantified by calculating the percentage of the total tracking movement contributed by the saccadic system. The patients with smooth-pursuit impairment exhibited a higher percentage of saccadic tracking and a lower smooth pursuit gain compared to the normal subjects. One patient with a unilateral lesion exhibited significant asymmetry in the smooth-pursuit component. In this case, the direction of the asymmetry indicated the side of the lesion.


Assuntos
Doenças do Sistema Nervoso/fisiopatologia , Acompanhamento Ocular Uniforme/fisiologia , Adulto , Feminino , Humanos , Masculino , Movimentos Sacádicos/fisiologia , Processamento de Sinais Assistido por Computador , Acuidade Visual
12.
Aviat Space Environ Med ; 66(3): 276-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7661842

RESUMO

Symptomatic sphenoid sinus pneumoceles are extremely rare. This case presented in a U.S. Air Force aviator who had recurrent left-sided visual loss during ascent in jet aircraft. Computed tomography showed a dehiscent optic nerve within the left sphenoid sinus. Surgical correction included removing a mucosal polyp from the sinus ostium. The aviator has since flown 70 sorties without recurrence of symptoms. This entity is named barosinus pneumocele.


Assuntos
Aeronaves , Embolia Aérea , Militares , Pólipos/complicações , Seio Esfenoidal , Transtornos da Visão/etiologia , Adulto , Humanos , Masculino , Doenças dos Seios Paranasais/complicações , Doenças dos Seios Paranasais/diagnóstico por imagem , Pólipos/diagnóstico por imagem , Radiografia , Seio Esfenoidal/diagnóstico por imagem , Estados Unidos
13.
Aviat Space Environ Med ; 69(1): 40-4, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9451532

RESUMO

BACKGROUND: The effect of high levels of linear acceleration (G) on the cochlea has never been studied prospectively. HYPOTHESIS: Linear acceleration at high levels has no effect on the human cochlea as demonstrated by a comparison of pre- and post-exposure measurements. METHODS: There were 22 healthy volunteers who underwent exposure to up to 9 G in a military aviation training centrifuge. Prior to exposure they were screened for cochleovestibular disorders and underwent tympanometry, audiometry and distortion product otoacoustic emissions testing (DPOAE). Immediately after exposure, they underwent serial testing of each of these parameters until they returned to baseline. RESULTS: There was no significant change in tympanometry in any subject. Audiometry revealed a temporary threshold shift of 30 db at 6 kHz in one ear of a single subject. This was accompanied by a complete loss of DPOAE at the same frequency. DPOAE did not return to baseline at 2 weeks even though the audiogram had reverted to baseline by 8 d. Four other ears displayed significant losses of emissions at single frequencies without an accompanying change on the audiogram. CONCLUSIONS: This study demonstrates that accelerative stress may cause transient injury to the cochlea. The mechanism of injury due to acceleration is probably ischemia, although a purely mechanical effect on the outer hair cells cannot be precluded. These data also reinforce a growing body of evidence that demonstrates the greater sensitivity of DPOAE over psychoacoustic testing in detecting early or subclinical cochlear damage.


Assuntos
Aceleração/efeitos adversos , Testes de Impedância Acústica/normas , Cóclea/lesões , Transtornos da Audição/diagnóstico , Transtornos da Audição/fisiopatologia , Hipergravidade/efeitos adversos , Emissões Otoacústicas Espontâneas/fisiologia , Testes de Impedância Acústica/métodos , Adulto , Audiometria de Tons Puros , Limiar Auditivo , Feminino , Transtornos da Audição/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Med Hypotheses ; 80(5): 656-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23414680

RESUMO

There are many published studies about the epigenetic effects of the prenatal and infant periods on health outcomes. However, there is very little knowledge regarding the effects of the intrapartum period (labor and birth) on health and epigenetic remodeling. Although the intrapartum period is relatively short compared to the complete perinatal period, there is emerging evidence that this time frame may be a critical formative phase for the human genome. Given the debates from the National Institutes of Health and World Health Organization regarding routine childbirth procedures, it is essential to establish the state of the science concerning normal intrapartum epigenetic physiology. EPIIC (Epigenetic Impact of Childbirth) is an international, interdisciplinary research collaboration with expertise in the fields of genetics, physiology, developmental biology, epidemiology, medicine, midwifery, and nursing. We hypothesize that events during the intrapartum period - specifically the use of synthetic oxytocin, antibiotics, and cesarean section - affect the epigenetic remodeling processes and subsequent health of the mother and offspring. The rationale for this hypothesis is based on recent evidence and current best practice.


Assuntos
Cesárea , Epigênese Genética/genética , Epigenômica/métodos , Doenças do Recém-Nascido/genética , Trabalho de Parto/genética , Modelos Genéticos , Feminino , Humanos , Recém-Nascido , Gravidez
17.
J Infect Dis ; 176(1): 258-61, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9207377

RESUMO

Endogenous expression of antisense RNA in transfected cells has been explored for use in blocking cellular gene expression and for its antiviral potential. Antisense strategies were used with the goal of blocking measles virus (MV) infection. A recombinant expression plasmid was designed to produce antisense oligonucleotides targeted to the 5' end of the MV nucleocapsid protein mRNA. This construct was transfected into HeLa cells. The transfected cell line and a control cell line expressing a random RNA comprising the same nucleotides were infected with MV and assessed for viral resistance by observation of cytopathic effect (CPE); infectious virus was quantified by viral plaque assay. Both cell lines were also infected with a related paramyxovirus, mumps virus, as a specificity control. Both CPE and infectious virus were reduced by approximately 90% in the antisense-expressing line compared with that in control cells or transfectant cells expressing random RNA. There was no evidence of resistance to infection with mumps virus in any cell line.


Assuntos
Sarampo/imunologia , RNA Antissenso/fisiologia , Efeito Citopatogênico Viral , Células HeLa , Humanos , Vírus do Sarampo/genética , Transfecção
18.
Virology ; 232(2): 241-7, 1997 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9191837

RESUMO

Measles virus (MV) suppresses specific functions in cells of the immune system and causes a generalized immunosuppression by mechanisms which remain undefined. It has been previously established that mitogen-induced proliferation of peripheral blood mononuclear cells (PBMC) is suppressed by infection with MV. Our current study demonstrates that MV infection inhibits antigen-specific proliferation of T lymphocytes. The inhibition of proliferation was not due to a decrease in IL-2 production. IL-2 production in cultures of infected and uninfected antigen-specific T cells was similar. In contrast, we found that expression of the IL-2R alpha subunit was decreased in mitogen-stimulated, MV-infected PBMC and antigen-stimulated, MV-infected T lymphocytes compared to stimulated but noninfected T cells. However, the expression of the IL-2R beta subunit was not altered in MV-infected T cells. We also examined the influence of MV infection on the production of the cytokines IL-4, IL-6, IL-10, and IFN-gamma by T lymphocytes. By comparing infected versus uninfected antigen-specific T cell lines, we found that MV infection of antigen-specific activated T cells caused no substantial change in generation of IFN-gamma, IL-6, or IL-10. There was a 50% reduction in IL-4 generation following MV infection. These data indicate that the immunosuppression by acute MV infection is not associated with a generalized inhibition of cytokine production. One mechanism for the suppression of proliferation following acute MV infection may be a block in the expression of the IL-2R alpha subunit by activated T cells.


Assuntos
Linfócitos T CD4-Positivos/virologia , Citocinas/biossíntese , Vírus do Sarampo/fisiologia , Receptores de Interleucina-2/biossíntese , Linfócitos T CD4-Positivos/imunologia , Divisão Celular , Linhagem Celular Transformada , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Mitógenos/farmacologia , Proteína Básica da Mielina/imunologia , Fito-Hemaglutininas/farmacologia , Toxoide Tetânico/imunologia , Tuberculina/imunologia
19.
Biospectroscopy ; 4(2): 107-11, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9557905

RESUMO

The backscattered Raman and Raman optical activity (ROA) spectra of poly(rA)-poly(rU) at 20 degrees C and 45 degrees C in buffered aqueous solution between 650 and 1750 cm(-1) are reported. Although the intensity of the majority of the Raman bands increase by varying amounts as the temperature is raised in accordance with the well-known hypochromic effect, the reverse effect is found for the ROA signals which we attribute to thermal accessibility of a greater number of distinct conformations leading to cancellation of ROA signals. The difference ROA spectrum obtained by subtracting the spectrum recorded at 45 degrees C from that recorded at 20 degrees C displays a very similar sign pattern to those at both 20 degrees C and 45 degrees C throughout the spectral region examined. This indicates that the same average structure is maintained in this temperature range and that the thermal fluctuations are correlated through the bases, the glycosidic link, the sugar ring, and the phosphate backbone of both strands. These results indicate that ROA may be a useful new probe of the dynamics of nucleic acid in solution.


Assuntos
Poli A-U/química , Polinucleotídeos/química , Análise Espectral Raman , Conformação Proteica , Temperatura
20.
Biochemistry ; 39(15): 4423-31, 2000 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-10757992

RESUMO

We present Raman spectra, obtained using 752 nm excitation, on wild-type GFP and the S65T mutant of this intrinsically fluorescent protein together with data on a model chromophore, ethyl 4-(4-hydroxyphenyl)methylidene-2-methyl-5-oxoimidazolacetate . In the pH range 1-14, the model compound has two macroscopic pK(a)s of 1.8 and 8.2 attributed to ionization of the imidazolinone ring nitrogen and the phenolic hydroxyl group, respectively. Comparison of the model chromophore with the chromophore in wild-type GFP and the S65T mutant reveals that the cationic form, with both the imidazolinone ring nitrogen and the phenolic oxygen protonated, is not present in these particular GFP proteins. Our results do not provide any evidence for the zwitterionic form of the chromophore, with the phenolic group deprotonated and the imidazolinone ring nitrogen protonated, being present in the GFP proteins. In addition, since the position of the Raman bands is a property exclusively of the ground state structure, the data enable us to investigate how protein-chromophore interactions affect the ground state structure of the chromophore without contributions from excited state effects. It is found that the ground state structure of the anionic form of the chromophore, which is most relevant to the fluorescent properties, is strongly dependent on the chromophore environment whereas the neutral form seems to be insensitive. A linear correlation between the absorption properties and the ground state structure is demonstrated by plotting the absorption maxima versus the wavenumber of a Raman band found in the range 1610-1655 cm(-1).


Assuntos
Acetatos/química , Ácidos Cumáricos , Corantes Fluorescentes/química , Imidazóis/química , Proteínas Luminescentes/química , Acetatos/síntese química , Acetatos/metabolismo , Acil Coenzima A/química , Acil Coenzima A/metabolismo , Acil-CoA Desidrogenase , Substituição de Aminoácidos/genética , Ânions/química , Ânions/metabolismo , Soluções Tampão , Cátions/química , Cátions/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Proteínas de Fluorescência Verde , Humanos , Concentração de Íons de Hidrogênio , Imidazóis/síntese química , Imidazóis/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Mutação/genética , Nitrogênio/metabolismo , Oxigênio/metabolismo , Desnaturação Proteica , Prótons , Solventes , Análise Espectral Raman
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA