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1.
Prehosp Emerg Care ; : 1-5, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38805385

RESUMO

OBJECTIVES: This study sought to evaluate performance indicators to assist a static-based 9-1-1 agency in defining its response efficiency. METHODS: Initial assessment of three metrics-unit hour utilization (UHU), fractile response intervals, and level 0 frequency (occurrence when no ambulances are available to respond)-suggested the agency's response over its four coverage zones was inefficient, so an operational change was implemented: an ambulance was relocated from one service area to another to improve the overall response productivity. A 2-year retrospective analysis was performed to determine the impact ambulance relocation had on the three targeted measurements. RESULTS: The operational change resulted in a statistically significant change in unit hour utilization, a non-significant increase in fractile response intervals, and a statistically significant reduction in level 0 frequency from pre- to post-operational change times. CONCLUSIONS: These findings suggest a way to evaluate the efficiency of static-based ambulance deployment and potentially identify strategies for redeployment.

2.
Biol Cell ; 113(12): 507-521, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523154

RESUMO

BACKGROUND: Over 400 million people are diabetic. Type 1 and type 2 diabetes are characterized by decreased functional ß-cell mass and, consequently, decreased glucose-stimulated insulin secretion. A potential intervention is transplantation of ß-cell containing islets from cadaveric donors. A major impediment to greater application of this treatment is the scarcity of transplant-ready ß-cells. Therefore, inducing ß-cell proliferation ex vivo could be used to expand functional ß-cell mass prior to transplantation. Various molecular pathways are sufficient to induce proliferation of young ß-cells; however, aged ß-cells are refractory to these proliferative signals. Given that the majority of cadaveric donors fit an aged demographic, defining the mechanisms that impede aged ß-cell proliferation is imperative. RESULTS: We demonstrate that aged rat (5-month-old) ß-cells are refractory to mitogenic stimuli that otherwise induce young rat (5-week-old) ß-cell proliferation. We hypothesized that this change in proliferative capacity could be due to differences in cyclin-dependent kinase inhibitor expression. We measured levels of p16INK4a , p15INK4b , p18INK4c , p19INK4d , p21CIP1 , p27KIP1 and p57KIP2 by immunofluorescence analysis. Our data demonstrates an age-dependent increase of p27KIP1 in rat ß-cells by immunofluorescence and was validated by increased p27KIP1 protein levels by western blot analysis. Interestingly, HDAC1, which modulates the p27KIP1 promoter acetylation state, is downregulated in aged rat islets. These data demonstrate increased p27KIP1 protein levels at 5 months of age, which may be due to decreased HDAC1 mediated repression of p27KIP1 expression. SIGNIFICANCE: As the majority of transplant-ready ß-cells come from aged donors, it is imperative that we understand why aged ß-cells are refractory to mitogenic stimuli. Our findings demonstrate that increased p27KIP1 expression occurs early in ß-cell aging, which corresponds with impaired ß-cell proliferation. Furthermore, the correlation between HDAC1 and p27 levels suggests that pathways that activate HDAC1 in aged ß-cells could be leveraged to decrease p27KIP1 levels and enhance ß-cell proliferation.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animais , Ciclo Celular , Proteínas de Ciclo Celular , Divisão Celular , Proliferação de Células , Ratos
3.
Life Sci Space Res (Amst) ; 24: 64-82, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31987481

RESUMO

Human missions to establish surface habitats on the Moon and Mars are planned in the coming decades. Extraplanetary surface habitat life support systems (LSS) will require new capabilities to withstand anticipated unique, harsh conditions. In order to provide safe, habitable environments for the crew, water purification systems that are robust and reliable must be in place. These water purification systems will be required to treat all sources of water in order to achieve the necessary levels of recovery needed to sustain life over the long-duration missions. Current water recovery and purification systems aboard the International Space Station (ISS) are only partially closed, requiring external inputs and resupply. Furthermore, organic wastes, such as fecal and food wastes, are currently discarded and not recycled. For long-duration missions and habitats, this is not a viable approach. The inability to recycle organic wastes represents a lost opportunity to recover critical elements (e.g., C, H, O, N, P) for subsequent food production, water purification, and atmospheric regeneration. On Earth, a variety of technologies are available to meet terrestrial wastewater treatment needs; however, these systems are rarely completely closed-loop, due to lack of economic drivers, legacy infrastructure, and the (perceived) abundance of resources on Earth. Extraplanetary LSS provides a game-changing opportunity to incentivize the development of completely closed-loop systems. Candidate technologies may be biological, physical, or chemical, with associated advantages and disadvantages. This paper presents a survey of potential technologies, along with their inputs, outputs and requirements, which may be suitable for next-generation regenerative water purification in space. With this information, particular technologies can be down-selected for subsystem integration testing and optimization. In order for future space colonies to have closed-loop systems which minimize consumable inputs and maximize recovery, strategic implementation of a variety of complementary subsystems is needed.


Assuntos
Meio Ambiente Extraterreno , Voo Espacial , Purificação da Água/métodos , Destilação/métodos
4.
Biochem J ; 475(24): 3997-4010, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30322885

RESUMO

The homeobox transcription factor Nkx6.1 is sufficient to increase functional ß-cell mass, where functional ß-cell mass refers to the combination of ß-cell proliferation, glucose-stimulated insulin secretion (GSIS) and ß-cell survival. Here, we demonstrate that the histone deacetylase 1 (HDAC1), which is an early target of Nkx6.1, is sufficient to increase functional ß-cell mass. We show that HDAC activity is necessary for Nkx6.1-mediated proliferation, and that HDAC1 is sufficient to increase ß-cell proliferation in primary rat islets and the INS-1 832/13 ß-cell line. The increase in HDAC1-mediated proliferation occurs while maintaining GSIS and increasing ß-cell survival in response to apoptotic stimuli. We demonstrate that HDAC1 overexpression results in decreased expression of the cell cycle inhibitor Cdkn1b/p27 which is essential for inhibiting the G1 to S phase transition of the cell cycle. This corresponds with increased expression of key cell cycle activators, such as Cyclin A2, Cyclin B1 and E2F1, which are activated by activation of the Cdk4/Cdk6/Cyclin D holoenzymes due to down-regulation of Cdkn1b/p27. Finally, we demonstrate that overexpression of Cdkn1b/p27 inhibits HDAC1-mediated ß-cell proliferation. Our data suggest that HDAC1 is critical for the Nkx6.1-mediated pathway that enhances functional ß-cell mass.


Assuntos
Proliferação de Células/fisiologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação para Baixo/fisiologia , Regulação Enzimológica da Expressão Gênica , Histona Desacetilase 1/biossíntese , Células Secretoras de Insulina/metabolismo , Animais , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p27/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p27/genética , Histona Desacetilase 1/genética , Humanos , Masculino , Ratos , Ratos Wistar
5.
Curr Pharm Des ; 13(2): 241-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17269931

RESUMO

The importance of pharmacogenetics in medicine is growing with the identification of genetic variability by faster screening methods using automatic sequencers. A particularly interesting finding is that apart from environmental and psychological factors, drug response may be influenced by several biological factors as a result of genetic determinants leading to interindividual variability. Several mutations in genes coding for enzymes of the drug metabolizing system, as well as for neurotransmitter receptors or degrading enzymes and monoamine transport proteins, have been identified and investigated in psychiatry. But, despite the fact that some genetic polymorphisms of enzymes (mainly cytochrome P450 2D6) are well known, the application of pharmacogenetics as a therapeutic tool for improving patient care is rare. This review has three parts. In the first an overview is given of CYP450 characteristics and the genetic polymorphisms of interest to psychiatry. In the second the clinical implications of the CYP2D6 polymorphism are reviewed and in the third part other aspects on pharmacogenetic research in psychiatry are discussed. The aim of our review is to promote the application of pharmacogenetics in everyday clinical practice.


Assuntos
Citocromo P-450 CYP2D6/genética , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/genética , Farmacogenética/métodos , Polimorfismo Genético/genética , Psiquiatria/métodos , Animais , Citocromo P-450 CYP2D6/fisiologia , Humanos , Transtornos Mentais/enzimologia
6.
J Virol ; 75(16): 7375-83, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11462009

RESUMO

Nucleocytoplasmic transport of viral ribonucleoproteins (vRNPs) is an essential aspect of the replication cycle for influenza A, B, and C viruses. These viruses replicate and transcribe their genomes in the nuclei of infected cells. During the late stages of infection, vRNPs must be exported from the nucleus to the cytoplasm prior to transport to viral assembly sites on the cellular plasma membrane. Previously, we demonstrated that the influenza A virus nuclear export protein (NEP, formerly referred to as the NS2 protein) mediates the export of vRNPs. In this report, we suggest that for influenza B and C viruses the nuclear export function is also performed by the orthologous NEP proteins (formerly referred to as the NS2 protein). The influenza virus B and C NEP proteins interact in the yeast two-hybrid assay with a subset of nucleoporins and with the Crm1 nuclear export factor and can functionally replace the effector domain from the human immunodeficiency virus type 1 Rev protein. We established a plasmid transfection system for the generation of virus-like particles (VLPs) in which a functional viral RNA-like chloramphenicol acetyltransferase (CAT) gene is delivered to a new cell. VLPs generated in the absence of the influenza B virus NEP protein were unable to transfer the viral RNA-like CAT gene to a new cell. From these data, we suggest that the nuclear export of the influenza B and C vRNPs are mediated through interaction between NEP proteins and the cellular nucleocytoplasmic export machinery.


Assuntos
Gammainfluenzavirus/fisiologia , Vírus da Influenza B/fisiologia , Proteínas não Estruturais Virais/fisiologia , Transporte Ativo do Núcleo Celular , Animais , Gatos , Linhagem Celular , Cães , Humanos , Replicação Viral
7.
J Virol ; 74(17): 7989-96, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10933707

RESUMO

We present a novel mechanism by which viruses may inhibit the alpha/beta interferon (IFN-alpha/beta) cascade. The double-stranded RNA (dsRNA) binding protein NS1 of influenza virus is shown to prevent the potent antiviral interferon response by inhibiting the activation of interferon regulatory factor 3 (IRF-3), a key regulator of IFN-alpha/beta gene expression. IRF-3 activation and, as a consequence, IFN-beta mRNA induction are inhibited in wild-type (PR8) influenza virus-infected cells but not in cells infected with an isogenic virus lacking the NS1 gene (delNS1 virus). Furthermore, NS1 is shown to be a general inhibitor of the interferon signaling pathway. Inhibition of IRF-3 activation can be achieved by the expression of wild-type NS1 in trans, not only in delNS1 virus-infected cells but also in cells infected with a heterologous RNA virus (Newcastle disease virus). We propose that inhibition of IRF-3 activation by a dsRNA binding protein significantly contributes to the virulence of influenza A viruses and possibly to that of other viruses.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Vírus da Influenza A/fisiologia , Fatores de Transcrição/metabolismo , Ativação Transcricional , Proteínas não Estruturais Virais/metabolismo , Animais , Western Blotting , Linhagem Celular , Embrião de Galinha , Proteínas de Ligação a DNA/antagonistas & inibidores , Humanos , Fator Regulador 3 de Interferon , Interferon beta/metabolismo , Mutação , Vírus da Doença de Newcastle/fisiologia , RNA Mensageiro/metabolismo , Respirovirus/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/antagonistas & inibidores , Transfecção , Proteínas não Estruturais Virais/genética
8.
Proc Natl Acad Sci U S A ; 97(8): 4309-14, 2000 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-10725408

RESUMO

We propose a rational approach to the generation of live viral vaccines: alteration of virally encoded type I IFN antagonists to attenuate virulence while retaining immunogenicity. We have explored this concept by using the influenza virus. Previously we have shown that the NS1 protein of influenza A virus possesses anti-IFN activity. We now present evidence that influenza A and B viruses encoding altered viral NS1 proteins are highly attenuated in the mouse host, yet provide protection from challenge with wild-type viruses.


Assuntos
Vírus da Influenza A/genética , Vírus da Influenza B/genética , Vacinas contra Influenza/genética , Proteínas não Estruturais Virais/genética , Animais , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , Primers do DNA , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Sítio-Dirigida , Células Vero , Proteínas não Estruturais Virais/imunologia
9.
EMBO J ; 17(1): 288-96, 1998 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-9427762

RESUMO

Nuclear import and export of viral nucleic acids is crucial for the replication cycle of many viruses, and elucidation of the mechanism of these steps may provide a paradigm for understanding general biological processes. Influenza virus replicates its RNA genome in the nucleus of infected cells. The influenza virus NS2 protein, which had no previously assigned function, was shown to mediate the nuclear export of virion RNAs by acting as an adaptor between viral ribonucleoprotein complexes and the nuclear export machinery of the cell. A functional domain on the NS2 with characteristics of a nuclear export signal was mapped: it interacts with cellular nucleoporins, can functionally replace the effector domain of the human immunodeficiency virus type 1 (HIV-1) Rev protein and mediates rapid nuclear export when cross-linked to a reporter protein. Microinjection of anti-NS2 antibodies into infected cells inhibited nuclear export of viral ribonucleoproteins, suggesting that the Rev-like NS2 mediates this process. Therefore, we have renamed this Rev-like factor the influenza virus nuclear export protein or NEP. We propose a model by which NEP acts as a protein adaptor molecule bridging viral ribonucleoproteins and the nuclear pore complex.


Assuntos
Núcleo Celular/metabolismo , Orthomyxoviridae/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Transporte Biológico , Microinjeções , Dados de Sequência Molecular , Porinas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/imunologia
10.
Virology ; 218(2): 335-42, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8610460

RESUMO

Previous work (C.F. Spiropoulou and S.T. Nichol, 1993, J. Virol. 67, 3103-3110) has demonstrated the existence in cells infected with the New Jersey serotype of vesicular stomatitis virus (VSV) of two small carboxy-coterminal proteins encoded by the P mRNA. These proteins have been named C' and C. We are interested in studying the function of these proteins in the virus life cycle. Toward this end, we have cloned the ORF encoding the potential C' protein of the Indiana serotype as a histidine-tagged fusion protein, purified the expressed protein from Escherichia coli, and used the fusion protein as an immunogen to raise antiserum in a rabbit. We have used this anti-C' protein serum to demonstrate that both of the predicted C' and C proteins are synthesized in cells infected with the Indiana serotype of VSV. In addition we have localized a portion of these proteins to nucleocapsids isolated from infected cells, suggesting that they may play a role in RNA synthesis. Reconstitution of the viral polymerase activity by expressing the L and P protein subunits with or without the C proteins failed to demonstrate any effect of the presence of these latter proteins on reconstituted transcription using purified nucleocapsids as templates. However, we have been able to show a dramatic stimulation of the polymerase activity in purified virions by the addition of purified C' protein to in vitro transcription reactions. Both the level and the fidelity of mRNA synthesis are stimulated by this protein. Evidence for the specificity of this effect comes from the fact that stimulation appears to be serotype specific; C' protein of the Indiana serotype stimulates transcription by purified Indiana serotype virions but has a minimal effect on transcription by purified virions of the New Jersey serotype. We are continuing our studies to determine the mechanism of this stimulation.


Assuntos
Transcrição Gênica/fisiologia , Vírus da Estomatite Vesicular Indiana/metabolismo , Vesiculovirus , Proteínas não Estruturais Virais/fisiologia , Animais , Anticorpos Antivirais , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Genes Virais/fisiologia , Histidina/genética , Fases de Leitura Aberta/genética , Peptídeos/genética , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , Coelhos , Proteínas Recombinantes de Fusão , Espermidina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Vírus da Estomatite Vesicular Indiana/imunologia , Proteínas não Estruturais Virais/análise , Proteínas não Estruturais Virais/biossíntese , Proteínas não Estruturais Virais/farmacologia , Vírion/química , Vírion/metabolismo
11.
Ann Biol Clin (Paris) ; 42(4): 307-15, 1984.
Artigo em Francês | MEDLINE | ID: mdl-6388428

RESUMO

Serodiagnosis in current practice by the method ELISA. Utilization of commercial kits. I. - Rubella. Comparative study with hemagglutination inhibition test. A comparative study of the hemagglutination inhibition test and the method ELISA for the serodiagnosis of rubella in current practice has been achieved on 1 000 sera using commercial products in kits. The conditions of utilization, the principal factors of the reaction and the expression of results in ELISA titres are defined. The results show a higher sensibility and a higher precision for ELISA and an uncertain interpretation concerning the low titres for IHA. The use of ELISA for the serodiagnosis of rubella in routine with the kit Rubelisa does not present any particular difficulty and raises the quality of the results.


Assuntos
Ensaio de Imunoadsorção Enzimática , Testes de Inibição da Hemaglutinação , Técnicas Imunoenzimáticas , Kit de Reagentes para Diagnóstico , Rubéola (Sarampo Alemão)/diagnóstico , Estudos de Avaliação como Assunto , Humanos , Testes Sorológicos
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