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1.
PLoS Comput Biol ; 6(12): e1001015, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21152000

RESUMO

Protein-protein interactions are often mediated by flexible loops that experience conformational dynamics on the microsecond to millisecond time scales. NMR relaxation studies can map these dynamics. However, defining the network of inter-converting conformers that underlie the relaxation data remains generally challenging. Here, we combine NMR relaxation experiments with simulation to visualize networks of inter-converting conformers. We demonstrate our approach with the apo Pin1-WW domain, for which NMR has revealed conformational dynamics of a flexible loop in the millisecond range. We sample and cluster the free energy landscape using Markov State Models (MSM) with major and minor exchange states with high correlation with the NMR relaxation data and low NOE violations. These MSM are hierarchical ensembles of slowly interconverting, metastable macrostates and rapidly interconverting microstates. We found a low population state that consists primarily of holo-like conformations and is a "hub" visited by most pathways between macrostates. These results suggest that conformational equilibria between holo-like and alternative conformers pre-exist in the intrinsic dynamics of apo Pin1-WW. Analysis using MutInf, a mutual information method for quantifying correlated motions, reveals that WW dynamics not only play a role in substrate recognition, but also may help couple the substrate binding site on the WW domain to the one on the catalytic domain. Our work represents an important step towards building networks of inter-converting conformational states and is generally applicable.


Assuntos
Biologia Computacional/métodos , Simulação de Dinâmica Molecular , Peptidilprolil Isomerase/química , Apoenzimas , Humanos , Ligação de Hidrogênio , Cadeias de Markov , Peptidilprolil Isomerase de Interação com NIMA , Ressonância Magnética Nuclear Biomolecular , Peptidilprolil Isomerase/metabolismo , Conformação Proteica , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína
2.
Am J Prev Med ; 33(4): 353-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17888862

RESUMO

BACKGROUND: Influenza surveillance is valuable for monitoring trends in influenza-related morbidity and mortality. Using the 2005-2006 influenza season as an example, this paper describes a comprehensive influenza surveillance program used by the California Department of Public Health (CDPH). METHODS: Data collected from patients evaluated for acute respiratory illness in a given week were reported and summarized the following week, including (1) electronic hospital pneumonia and influenza admission and antiviral usage records from Kaiser Permanente, (2) sentinel provider influenza-like illness (ILI) reports, (3) severe pediatric influenza case reports (e.g., children either hospitalized in intensive care or expired), (4) school clinic ILI evaluations, and (5) positive influenza test results from a network of academic, hospital, commercial, and public health laboratories and the state CDPH Viral and Rickettsial Disease Laboratory. RESULTS: Influenza activity in California in the 2005-2006 season was moderate in severity; all clinical and laboratory markers rose and fell consistently. Extensive laboratory characterization identified the predominant circulating virus strain as A/California/7/2004(H3N2), which was a component of the 2005-2006 influenza vaccine; 96% of samples tested showed adamantane resistance. CONCLUSIONS: By using multiple, complementary surveillance methods coupled with a strong laboratory component, the CDPH has developed a simple, flexible, stable, and widely accepted influenza surveillance system that can monitor trends in statewide influenza activity, ascertain the correlation between circulating strains with vaccine strains, and assist with detection of new strain variants. The methods described can serve as a model for influenza surveillance in other states.


Assuntos
Alphainfluenzavirus/isolamento & purificação , Influenza Humana/epidemiologia , Vigilância da População/métodos , Estações do Ano , California/epidemiologia , Humanos , Influenza Humana/mortalidade , Modelos Organizacionais
3.
J Chem Phys ; 126(7): 074103, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17328589

RESUMO

The authors accelerate the replica exchange method through an efficient all-pairs replica exchange. A proof of detailed balance is shown along with an analytical estimate of the enhanced exchange efficiency. The new method provides asymptotically four fold speedup of conformation traversal for replica counts of 8 and larger with typical exchange rates. Experimental tests using the blocked alanine dipeptide demonstrate the method's correctness and show an approximate sampling efficiency improvement of 100% according to potential energy cumulative averages and an ergodic measure. An explicitly solvated PIN1 WW domain system of 4958 atoms is sampled using our new method, yielding a cluster sampling rate almost twice that of the single exchange near neighbor implementation. Computational software and scripts along with input and output data sets are available at.


Assuntos
Dipeptídeos/química , Modelos Químicos , Peptidilprolil Isomerase/química , Conformação Proteica , Proteínas/química , Algoritmos , Simulação por Computador , Modelos Moleculares , Peptidilprolil Isomerase de Interação com NIMA , Estrutura Terciária de Proteína
5.
J Public Health Manag Pract ; Suppl: S38-44, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16205541

RESUMO

Meeting the complex needs of a school system and all its members in the event of a bioterrorism (BT) disaster demands a competent workforce. School nurses are in position to be key contributors to planning for and responding to potential BT and disaster events. As part of a state preparedness leadership institute, the BT and disaster preparedness needs of school nurses in a three-county area were assessed and the nurses' preferred method to meet those needs was determined. Using competencies derived from publications by the Centers for Disease Control and Prevention and National Association of School Nurses, a survey was created and mailed to school nurses (N = 125) in public and private k-12 schools. Eighty surveys were returned (64% response rate). Responses were analyzed according to BT and emergency preparedness competencies and skills required for the phases of emergency management: mitigation, preparedness, response, and recovery. Low confidence in preparedness capabilities across almost all categories was reported. High training need was identified across almost all competencies, with 63 percent to 70 percent requesting additional education related to emergency response, infectious disease, hazardous materials, and diagnostic criteria. Although two-thirds report having Internet access in their school office, traditional classroom instruction was overwhelmingly preferred (74%) for training.


Assuntos
Atitude do Pessoal de Saúde , Conscientização , Bioterrorismo , Planejamento em Desastres/estatística & dados numéricos , Serviços de Enfermagem Escolar , Humanos , Ohio , Saúde Pública , Inquéritos e Questionários
6.
Death Stud ; 28(2): 111-35, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14971412

RESUMO

Grounded theory methods were used to study the experiences of 8 bereaved fathers whose children received care in a home-based hospice program. In-depth, unstructured interviews were audiotaped, transcribed, and coded for themes and categories. Every aspect of fathers' lives was affected by their experiences, which were described in metaphoric terms as living in a dragon's shadow. Fathers dealt with life in the dragon's shadow by battling the dragon (the illness)--the core social process. Battling was a conscious, active, continuous process that required strength, willpower, and work. Battling occurred within the context of fathers' experiences with fathering and fatherhood and was characterized by 3 aspects: battling with uncertainty, battling with responsibility, and battling with everyday disruption. Fathers were assisted by supportive work environments and by supportive relationships with health care providers. Unsatisfactory relationships with medical personnel compounded fathers' battling with life in the dragon's shadow.


Assuntos
Luto , Criança , Doença Crônica/psicologia , Pai/psicologia , Doente Terminal/psicologia , Adaptação Psicológica , Adulto , Relações Pai-Filho , Humanos , Masculino , Apoio Social , Incerteza
8.
J Palliat Care ; 18(1): 59-67, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12001404

RESUMO

Hospice and palliative care principles mandate clinicIans to provide "total" care to patients and their families. Such care incorporates not only physical, emotional, and psychosocial care, but spiritual care as well. Even though considerable attention has been directed to spiritual issues for adult patients in hospice and palliative care, spirituality in pediatric palliative care has been virtually neglected. The need for guidelines to assess spirituality in this population was identified as a priority issue by members of a subcommittee of the Children's International Project on Children's Palliative/Hospice Services, created under the auspices of the National Hospice Organization. Committee members, based on their clinical, research, and personal experiences, identified several aspects relevant to spirituality in general, and to spirituality in pediatric palliative care in particular, and developed guidelines for clinicians in pediatric palliative care. The purpose of this paper is to share the results of this committee's work and, in particular, to present their guidelines for addressing spiritual issues in children and families in pediatric hospice and palliative care.


Assuntos
Saúde Holística , Cuidados Paliativos/métodos , Cuidados Paliativos/psicologia , Assistência Religiosa/métodos , Pediatria/métodos , Guias de Prática Clínica como Assunto , Psicologia da Criança , Espiritualidade , Adulto , Criança , Família/psicologia , Humanos , Avaliação das Necessidades , Avaliação em Enfermagem , Cuidados Paliativos/normas , Assistência Religiosa/normas , Religião e Medicina , Religião e Psicologia
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