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1.
Proc Natl Acad Sci U S A ; 115(8): E1799-E1808, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29432185

RESUMO

α-Helical membrane proteins have eluded investigation of their thermodynamic stability in lipid bilayers. Reversible denaturation curves have enabled some headway in determining unfolding free energies. However, these parameters have been limited to detergent micelles or lipid bicelles, which do not possess the same mechanical properties as lipid bilayers that comprise the basis of natural membranes. We establish reversible unfolding of the membrane transporter LeuT in lipid bilayers, enabling the comparison of apparent unfolding free energies in different lipid compositions. LeuT is a bacterial ortholog of neurotransmitter transporters and contains a knot within its 12-transmembrane helical structure. Urea is used as a denaturant for LeuT in proteoliposomes, resulting in the loss of up to 30% helical structure depending upon the lipid bilayer composition. Urea unfolding of LeuT in liposomes is reversible, with refolding in the bilayer recovering the original helical structure and transport activity. A linear dependence of the unfolding free energy on urea concentration enables the free energy to be extrapolated to zero denaturant. Increasing lipid headgroup charge or chain lateral pressure increases the thermodynamic stability of LeuT. The mechanical and charge properties of the bilayer also affect the ability of urea to denature the protein. Thus, we not only gain insight to the long-sought-after thermodynamic stability of an α-helical protein in a lipid bilayer but also provide a basis for studies of the folding of knotted proteins in a membrane environment.


Assuntos
Proteínas de Bactérias/química , Bicamadas Lipídicas/química , Proteínas de Membrana/química , Desdobramento de Proteína , Modelos Moleculares , Conformação Proteica , Desnaturação Proteica , Termodinâmica
3.
Artigo em Inglês | MEDLINE | ID: mdl-25570742

RESUMO

Over the last decade the changing healthcare environment has required hospitals and specifically Biomedical Engineering to critically evaluate, optimize and adapt their operations. The focus is now on new technologies, changes to the environment of care, support requirements and financial constraints. Memorial Sloan Kettering Cancer Center (MSKCC), an NIH-designated comprehensive cancer center, has been transitioning to an increasing outpatient care environment. This transition is driving an increase in-patient acuity coupled with the need for added urgency of support and response time. New technologies, regulatory requirements and financial constraints have impacted operating budgets and in some cases, resulted in a reduction in staffing. Specific initiatives, such as the Joint Commission's National Patient Safety Goals, requirements for an electronic medical record, meaningful use and ICD10 have caused institutions to reevaluate their operations and processes including requiring Biomedical Engineering to manage new technologies, integrations and changes in the electromagnetic environment, while optimizing operational workflow and resource utilization. This paper addresses the new and expanding responsibilities and approach of Biomedical Engineering organizations, specifically at MSKCC. It is suggested that our experience may be a template for other organizations facing similar problems. Increasing support is necessary for Medical Software - Medical Device Data Systems in the evolving wireless environment, including RTLS and RFID. It will be necessary to evaluate the potential impact on the growing electromagnetic environment, on connectivity resulting in the need for dynamic and interactive testing and the growing demand to establish new and needed operational synergies with Information Technology operations and other operational groups within the institution, such as nursing, facilities management, central supply, and the user departments.


Assuntos
Tecnologia Biomédica , Engenharia Biomédica , Atenção à Saúde , Sistemas de Comunicação no Hospital , Hospitais , Humanos , Serviço Hospitalar de Engenharia e Manutenção , Assistência ao Paciente , Melhoria de Qualidade , Software , Tecnologia sem Fio
5.
J Environ Manage ; 97: 28-37, 2012 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-22325580

RESUMO

The Water Framework Directive (WFD) aims to deliver good ecological status (GES) for Europe's waters. It prescribes the use of economic principles, such as derogation from GES on grounds of disproportionate costs of mitigation. This paper proposes an application of the proportionality principle to mitigation of phosphorus (P) pollution of 544 Scottish lochs at national and local water body scales. P loading estimates were derived from a national diffuse pollution screening tool. For 293 of these lochs (31% of the loch area), GES already occurred. Mitigation cost-effectiveness was assessed using combined mitigation cost curves for managed grassland, rough grazing, arable land, sewage and septic tank sources. These provided sufficient mitigation (92% of national P load) for GES to be achieved on another 31% of loch area at annualised cost of £2.09 m/y. Mitigation of the residual P loading preventing other lochs achieving GES was considered by using a "mop-up" cost of £200/kg P (assumed cost effectiveness of removal of P directly from lochs), leading to a total cost of £189 m/y. Lochs were ranked by mitigation costs per loch area to give a national scale marginal mitigation cost curve. A published choice experiment valuation of WFD targets for Scottish lochs was used to estimate marginal benefits at national scale and combined with the marginal cost curve. This gave proportionate costs of £5.7 m/y leading to GES in 72% of loch area. Using national mean marginal benefits with a scheme to estimate changes in individual loch value with P loading gave proportionate costs of £25.6 m/y leading to GES in 77% of loch area (491 lochs).


Assuntos
Fósforo/análise , Poluição da Água/economia , Purificação da Água/economia , Água/química , Análise Custo-Benefício , Recuperação e Remediação Ambiental , Escócia , Poluição da Água/legislação & jurisprudência , Purificação da Água/legislação & jurisprudência
6.
Vet Rec ; 167(2): 59-63, 2010 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-20622205

RESUMO

Red squirrels (Sciurus vulgaris) found dead or dying on the Isle of Wight and the island of Jersey were suffering from exudative, ulcerative dermatitis and superficial staphylococcal pyoderma. The principal gross lesions were on the lips, eyelids and feet and showed similarities to those of squirrelpox. The histopathological lesions were also similar and, although there was no ballooning degeneration of epidermal cells, intracytoplasmic inclusions resembling those seen in poxvirus infections were present. Examination of lesions by electron microscopy failed to identify any virions, and PCR analysis for squirrelpox virus proved negative. The skin lesions also resembled those of mange, but although numerous mites were present in the fur these were mostly Dermacarus sciurinus with small numbers of Metalistrophorus pagenstecheri. The occurrence of these species on red squirrels in Britain is confirmed, but neither is pathogenic and they were not considered to have been involved in the pathogenesis of the dermatitis, the primary cause of which was not established.


Assuntos
Dermatite/veterinária , Sciuridae , Animais , Dermatite/mortalidade , Diagnóstico Diferencial , Exsudatos e Transudatos , Feminino , Doenças Labiais/patologia , Doenças Labiais/veterinária , Masculino , Microscopia Eletrônica/veterinária , Ácaros , Reação em Cadeia da Polimerase/veterinária , Pioderma/veterinária , Sciuridae/microbiologia , Sciuridae/parasitologia , Reino Unido/epidemiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-19964258

RESUMO

Increased technological complexity of medical devices and systems coupled with increased workloads and reduced staffing, have created difficulties and discontinuities in the management of patient information. These issues have directly impacted and contributed to a rise in equipment-related errors, patient dissatisfaction, a potential for patient injury and resulting overall increased concern for patient safety. In response these concerns a variety of new devices, systems and applications have been developed to share information, provide cross checks along with verified delivery of critical information to the point of care. These applications include biomedical information systems, medication administration, sample collection, and electronic medical records. The deployment of these new integrated and networked devices, systems and applications are dependent on an accurate and consistent patient identification and association methodology which dynamically manages the relationship between patients, staff and equipment. Since the association information is common to many applications and utilizes a variety of technologies, (i.e. active and passive radio frequency identification (RFID), barcodes, etc.) an institutional approach is necessary to mange these processes in a consistent manor utilizing a common set of identification hardware. Implementation of a "Patient Centric Identification and Association Platform" represents a significant advance in the management of clinical patient information. The implementation of a Biomedical Device Information Network at Memorial Sloan-Kettering Cancer Center (MSKCC) integrates the identification and association of patients with devices and care providers and provides the methodologies to manage alarms, providing the ability to filter low priority or nuisance alarms. This implementation enables critical information to be distributed directly to care providers utilizing dedicated communications devices. Patient Centric Identification and Association is the enabling technology providing precise identification and association establishing an enhanced environment of care, increased patient safety, and a clear proactive response to the regulatory requirements of the Joint Commission (JCAHO) national patient safety initiatives.


Assuntos
Sistemas de Identificação de Pacientes , Humanos , Sistemas de Informação , Erros Médicos/prevenção & controle , Satisfação do Paciente , Ondas de Rádio
8.
Vet Rec ; 161(13): 447-51, 2007 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-17906226

RESUMO

Haematological and biochemical data were collected over a period of six years from grey seal (Halichoerus grypus) pups undergoing rehabilitation. Pups bled during the first three days were allocated retrospectively to one of seven clinical groups and statistical analyses were carried out on six of these groups (130 pups). Compared with reference ranges, all the groups had lower mean packed-cell volumes (pcv), red blood cell (rbc) counts haemoglobin and albumin levels, pups with severe trauma had higher total white blood cell (wbc) and neutrophil counts, pups with severe trauma and malnourished pups had higher total bilirubin levels, and pups in all the clinical groups except those with severe trauma had lower sodium levels. There were significant differences (P<0.05) between some clinical groups for mean pcv, rbc counts, all wbc counts except monocytes, haemoglobin, total bilirubin, creatine kinase, amylase and potassium levels. Forty-nine pups were bled more than once during the first 10 days of rehabilitation for haematology, and 11 were bled more than once for biochemistry. There were significant decreases (P<0.05) during this period in pcv, and in the activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase and lactate dehydrogenase, and significant increases in all wbc counts, total protein, globulin, amylase and calcium levels.


Assuntos
Índices de Eritrócitos/veterinária , Contagem de Leucócitos/veterinária , Focas Verdadeiras/sangue , Ferimentos e Lesões/veterinária , Animais , Animais Recém-Nascidos/sangue , Animais Selvagens , Análise Química do Sangue/veterinária , Feminino , Testes Hematológicos/veterinária , Hemoglobinas/análise , Masculino , Desnutrição/sangue , Desnutrição/veterinária , Valores de Referência , Infecções Respiratórias/sangue , Infecções Respiratórias/veterinária , Focas Verdadeiras/lesões , Albumina Sérica/análise , Especificidade da Espécie , Ferimentos e Lesões/sangue , Ferimentos e Lesões/reabilitação
9.
Br Dent J ; 200(6): 303, 2006 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-16568035
10.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 109-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17946786

RESUMO

The deployment of new wireless and networked technology and advanced clinical applications has significantly increased the quality and the quantity of patient diagnostic and monitoring information throughout the patient care environment. Coupled with increasing workloads and reduced staffing, the difficulties in effectively prioritizing and handling this information have resulted in a rise in equipment-related errors, patient dissatisfaction, a potential for patient injury, and an increasing overall concern for patient safety. Concerns about this trend have prompted the Joint Commission to established seven patient safety initiatives geared to the patient environment of care, establishing methodologies and protocols to reduce the probability of errors, and to provide an enhanced level of communications. Planned deployment of advanced medical devices and supporting technologies coupled with our existing wired/wireless network infrastructure, need to consider the potential integrating clinical device, onto a unified network infrastructure providing advanced capabilities to share and effectively manage this key patient clinical information. Implementation of a biomedical device information network represents a significant advance in the management of clinical patient information, and enables device data, specifically critical patient alarms to be shared, coordinated, prioritized and sent directly to specific assigned care providers. The care giver utilizing a common hands-free wireless device can receive a prioritized audible (or a simulated voice) alarm message and utilize this same device for directed staff-to-staff or staff-to-patient communication. The Biomedical Information Network implementation identifies or associates patients with devices and consequently critical alarms, filters low priority or nuisance alarms, and eliminates the need for multiple costly communication devices. This implementation establishes an enhanced environment of care, providing increased patient safety, and a clear proactive response to the national patient safety initiatives.


Assuntos
Redes de Comunicação de Computadores , Sistemas de Gerenciamento de Base de Dados/instrumentação , Sistemas de Informação Hospitalar , Armazenamento e Recuperação da Informação/métodos , Sistemas Computadorizados de Registros Médicos/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Desenho de Equipamento , Análise de Falha de Equipamento , Equipamentos e Provisões , Informática Médica/instrumentação , Informática Médica/métodos , Integração de Sistemas
11.
Artigo em Inglês | MEDLINE | ID: mdl-17946788

RESUMO

Radio Frequency Identification (RFID) is an evolving technology that can utilize its capabilities within a healthcare environment to locate and track staff, equipment, and patients. RFID has the potential to significantly improve operations by actively monitoring asset flow through an organization and enabling this data to be analyzed for process improvement. It can also help to provide validation to existing process improvement initiatives set forth by an institution. Furthermore, RFID can be integrated into other operations including patient safety, clinical operations, billing, and theft prevention.


Assuntos
Prestação Integrada de Cuidados de Saúde/métodos , Equipamentos e Provisões Hospitalares , Inventários Hospitalares/métodos , Sistemas de Identificação de Pacientes/métodos , Rotulagem de Produtos/métodos , Medidas de Segurança , Telemetria/métodos , Prestação Integrada de Cuidados de Saúde/organização & administração , Inventários Hospitalares/organização & administração , Sistemas de Identificação de Pacientes/organização & administração , Estados Unidos
12.
Artigo em Inglês | MEDLINE | ID: mdl-17946785

RESUMO

Once the requirement for a biomedical information network has been articulated, the process of development and implementation can then be approached. Although the general architecture of such a system may appear to be self evident, there are careful design considerations that will allow the network to be robust and achieve increased levels of functionality as additional systems come on-line and become integrated into the network. As of this writing, there are few interoperability standards between the various medical systems that comprise the desired network. We have chosen the Emergin Orchestrator product (Boca Raton, Fl) as the vehicle for integrating these systems. The major design and implementation tasks include defining the basic information architecture, assessing the performance of the existing IT infrastructure, and understanding the native capabilities and limitations of each system involved in the network.


Assuntos
Redes de Comunicação de Computadores , Equipamentos e Provisões , Sistemas de Informação Hospitalar , Informática Médica/instrumentação , Informática Médica/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Desenho de Equipamento , Análise de Falha de Equipamento , Integração de Sistemas
13.
Arch Dis Child Fetal Neonatal Ed ; 90(6): F456-60, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16244206

RESUMO

Air transport of infants in incubators should be undertaken in a manner that is safe for both staff and infant and satisfies all directives by appropriate regulatory bodies. In Scotland during the last two years, certification of an infant incubator system for use in both rotary and fixed wing aircraft has been accomplished. This is a report of the issues addressed during this project, which will be common to all neonatal transport services intending to develop air transport capability.


Assuntos
Resgate Aéreo/normas , Enfermagem Neonatal/normas , Medicina Aeroespacial/normas , Altitude , Desenho de Equipamento , Humanos , Incubadoras para Lactentes/normas , Recém-Nascido , Respiração Artificial/normas , Escócia
14.
Phys Rev Lett ; 94(12): 122001, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15903906

RESUMO

We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic.

15.
Phys Rev Lett ; 94(9): 091803, 2005 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-15783955

RESUMO

We report the first measurements of inclusive W and Z cross sections times leptonic branching ratios for pp collisions at square root[s]=1.96 TeV, based on their decays to electrons and muons. The data correspond to an integrated luminosity of 72 pb(-1) recorded with the CDF detector at the Fermilab Tevatron. We test e-mu universality in W decays, and we measure the ratio of leptonic W and Z rates from which the leptonic branching fraction B(W-->lnu) can be extracted as well as an indirect value for the total width of the W and the Cabibbo-Kobayashi-Maskawa matrix element, |V(cs)|.

17.
Phys Rev Lett ; 93(22): 221802, 2004 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-15601082

RESUMO

We present the results of a search for doubly charged Higgs bosons (H+/-+/-) decaying to dileptons (ll(')) using approximately 240 pb(-1) of pp collision data collected by the CDF II experiment at the Fermilab Tevatron. In our search region, given by same-sign ll(') mass m(ll('))>80 GeV/c(2) (100 GeV/c(2) for ee channel), we observe no evidence for H+/-+/- production. We set limits on sigma(pp -->H++H---->l(+)l('+)l(-)l('-)) as a function of the mass of the H+/-+/- and the chirality of its couplings. Assuming exclusive same-sign dilepton decays, we derive lower mass limits on H(+/-+/-)(L) of 133, 136, and 115 GeV/c(2) in the ee, mumu, and emu channels, respectively, and a lower mass limit of 113 GeV/c(2) on H(+/-+/-)(R) in the mumu channel, all at the 95% confidence level.

18.
Phys Rev Lett ; 93(14): 142001, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15524782

RESUMO

We report a measurement of the tt production cross section using dilepton events with jets and missing transverse energy in pp collisions at a center-of-mass energy of 1.96 TeV. Using a 197+/-12 pb(-1) data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the standard model and find good agreement. The combined result of the two techniques yields a tt production cross section of 7.0(+2.4)(-2.1)(stat)+1.6-1.1(syst)+/-0.4(lum) pb.

19.
Phys Rev Lett ; 93(3): 032001, 2004 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-15323815

RESUMO

We report on a search for B(0)(s)-->micro(+)micro(-) and B(0)(d)-->micro(+)micro(-) decays in pp collisions at square root of s=1.96 TeV using 171 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the standard model. One event survives all our selection requirements, consistent with the background expectation. We derive branching ratio limits of B(B(0)(s)-->micro(+)micro(-))<5.8x10(-7) and B(B(0)(d)-->micro(+)micro(-))<1.5x10(-7) at 90% confidence level.

20.
Cloning Stem Cells ; 5(2): 133-42, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12930625

RESUMO

Early developmental kinetics of nuclear transfer (NT) embryos reconstituted with blastomeres and parthenogenones produced by ionophore activation followed by either dimethylaminopurine (DMAP) or cycloheximide (CHX) treatment was studied. In vitro produced (IVP) embryos served as controls. Embryos were cultured to the hatched blastocyst stage, and images were recorded every 0.5 h throughout the culture period. The longest cell cycle shifted from 4th to 5th cycle (26 +/- 4 and 44 +/- 5 h) in NT-embryos compared to IVP-embryos (41 +/- 2 and 20 +/- 3 h) and showed greater asynchrony between blastomeres than any other embryo category. Compared to DMAP, CHX prolonged the 1(st) (23 +/- 1 vs. 33 +/- 1 h) and shortened the 3(rd) cell cycle (17 +/- 2 vs. 13 +/- 1 h). Moreover, though cytoskeleton activity was initialised, a larger proportion of CHX embryos was unable to accomplish first cleavage. The parthegenones differed from IVP embryos with respect to the lengths of the 1st, 3rd, and 4th cell cycles and time of hatching. The findings are discussed in relation to known ultrastructural, chromosomal and genomic aberrations found in NT embryos and parthenogenones. We hypothesize that the shift of the longest cell cycle in NT embryos is associated with a shift in the time of major genomic transition.


Assuntos
Adenina/análogos & derivados , Bovinos/embriologia , Desenvolvimento Embrionário e Fetal , Técnicas de Transferência Nuclear , Partenogênese/genética , Adenina/farmacologia , Animais , Ciclo Celular , Células Cultivadas , Técnicas de Cultura , Cicloeximida/farmacologia , Feminino , Viabilidade Fetal , Cinética , Fatores de Tempo
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