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1.
J Pathol ; 263(4-5): 403-417, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38886898

RESUMO

The evolution of cancer treatment has provided increasingly targeted strategies both in the upfront and relapsed disease settings. Small-molecule inhibitors and immunotherapy have risen to prominence with chimeric antigen receptor T-cells, checkpoint inhibitors, kinase inhibitors, and monoclonal antibody therapies being deployed across a range of solid organ and haematological malignancies. However, novel approaches are required to target transcription factors and oncogenic fusion proteins that are central to cancer biology and have generally eluded successful drug development. Thalidomide analogues causing protein degradation have been a cornerstone of treatment in multiple myeloma, but a lack of in-depth mechanistic understanding initially limited progress in the field. When the protein cereblon (CRBN) was found to mediate thalidomide analogues' action and CRBN's neo-targets were identified, existing and novel drug development accelerated, with applications outside multiple myeloma, including non-Hodgkin's lymphoma, myelodysplastic syndrome, and acute leukaemias. Critically, transcription factors were the first canonical targets described. In addition to broadening the application of protein-degrading drugs, resistance mechanisms are being overcome and targeted protein degradation is widening the scope of druggable proteins against which existing approaches have been ineffective. Examples of targeted protein degraders include molecular glues and proteolysis targeting chimeras (PROTACs): heterobifunctional molecules that bind to proteins of interest and cause proximity-induced ubiquitination and proteasomal degradation via a linked E3 ligase. Twenty years since their inception, PROTACs have begun progressing through clinical trials, with early success in targeting the oestrogen receptor and androgen receptor in breast and prostate cancer respectively. This review explores important developments in targeted protein degradation to both treat and study cancer. It also considers the potential advantages and challenges in the translational aspects of developing new treatments. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias , Proteólise , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Terapia de Alvo Molecular , Animais
2.
MMWR Morb Mortal Wkly Rep ; 72(14): 366-371, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37022974

RESUMO

Circulating vaccine-derived poliovirus (cVDPV) outbreaks* can occur when oral poliovirus vaccine (OPV, containing one or more Sabin-strain serotypes 1, 2, and 3) strains undergo prolonged circulation in under-vaccinated populations, resulting in genetically reverted neurovirulent virus (1,2). Following declaration of the eradication of wild poliovirus type 2 in 2015 and the global synchronized switch from trivalent OPV (tOPV, containing Sabin-strain types 1, 2, and 3) to bivalent OPV (bOPV, containing types 1 and 3 only) for routine immunization activities† in April 2016 (3), cVDPV type 2 (cVDPV2) outbreaks have been reported worldwide (4). During 2016-2020, immunization responses to cVDPV2 outbreaks required use of Sabin-strain monovalent OPV2, but new VDPV2 emergences could occur if campaigns did not reach a sufficiently high proportion of children. Novel oral poliovirus vaccine type 2 (nOPV2), a more genetically stable vaccine than Sabin OPV2, was developed to address the risk for reversion to neurovirulence and became available in 2021. Because of the predominant use of nOPV2 during the reporting period, supply replenishment has frequently been insufficient for prompt response campaigns (5). This report describes global cVDPV outbreaks during January 2021-December 2022 (as of February 14, 2023) and updates previous reports (4). During 2021-2022, there were 88 active cVDPV outbreaks, including 76 (86%) caused by cVDPV2. cVDPV outbreaks affected 46 countries, 17 (37%) of which reported their first post-switch cVDPV2 outbreak. The total number of paralytic cVDPV cases during 2020-2022 decreased by 36%, from 1,117 to 715; however, the proportion of all cVDPV cases that were caused by cVDPV type 1 (cVDPV1) increased from 3% in 2020 to 18% in 2022, including the occurrence of cocirculating cVDPV1 and cVDPV2 outbreaks in two countries. The increased proportion of cVDPV1 cases follows a substantial decrease in global routine immunization coverage and suspension of preventive immunization campaigns during the COVID-19 pandemic (2020-2022) (6); outbreak responses in some countries were also suboptimal. Improving routine immunization coverage, strengthening poliovirus surveillance, and conducting timely and high-quality supplementary immunization activities (SIAs) in response to cVDPV outbreaks are needed to interrupt cVDPV transmission and reach the goal of no cVDPV isolations in 2024.


Assuntos
Surtos de Doenças , Poliomielite , Vacina Antipólio Oral , Criança , Humanos , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Poliovirus/genética , Vacina Antipólio Oral/efeitos adversos
3.
BMC Health Serv Res ; 23(1): 1386, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082421

RESUMO

BACKGROUND: Clostridioides difficile infection (CDI) is associated with considerable morbidity and mortality in hospitalized patients, especially among older adults. Probiotics have been evaluated to prevent hospital-acquired (HA) CDI in patients who are receiving systemic antibiotics, but the implementation of timely probiotic administration remains a challenge. We evaluated methods for effective probiotic implementation across a large health region as part of a study to assess the real-world effectiveness of a probiotic to prevent HA-CDI (Prevent CDI-55 +). METHODS: We used a stepped-wedge cluster-randomized controlled trial across four acute-care adult hospitals (n = 2,490 beds) to implement the use of the probiotic Bio-K + ® (Lactobacillus acidophilus CL1285®, L. casei LBC80R® and L. rhamnosus CLR2®; Laval, Quebec, Canada) in patients 55 years and older receiving systemic antimicrobials. The multifaceted probiotic implementation strategy included electronic clinical decision support, local site champions, and both health care provider and patient educational interventions. Focus groups were conducted during study implementation to identify ongoing barriers and facilitators to probiotic implementation, guiding needed adaptations of the implementation strategy. Focus groups were thematically analyzed using the Theoretical Domains Framework and the Consolidated Framework of Implementation Research. RESULTS: A total of 340 education sessions with over 1,800 key partners and participants occurred before and during implementation in each of the four hospitals. Site champions were identified for each included hospital, and both electronic clinical decision support and printed educational resources were available to health care providers and patients. A total of 15 individuals participated in 2 focus group and 7 interviews. Key barriers identified from the focus groups resulted in adaptation of the electronic clinical decision support and the addition of nursing education related to probiotic administration. As a result of modifying implementation strategies for identified behaviour change barriers, probiotic adherence rates were from 66.7 to 75.8% at 72 h of starting antibiotic therapy across the four participating acute care hospitals. CONCLUSIONS: Use of a barrier-targeted multifaceted approach, including electronic clinical decision support, education, focus groups to guide the adaptation of the implementation plan, and local site champions, resulted in a high probiotic adherence rate in the Prevent CDI-55 + study.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Probióticos , Humanos , Idoso , Lactobacillus acidophilus , Infecções por Clostridium/prevenção & controle , Probióticos/uso terapêutico , Antibacterianos/uso terapêutico , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/tratamento farmacológico , Hospitais
4.
PLoS Pathog ; 16(8): e1008836, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866212

RESUMO

Anthrax is a major zoonotic disease of wildlife, and in places like West Africa, it can be caused by Bacillus anthracis in arid nonsylvatic savannahs, and by B. cereus biovar anthracis (Bcbva) in sylvatic rainforests. Bcbva-caused anthrax has been implicated in as much as 38% of mortality in rainforest ecosystems, where insects can enhance the transmission of anthrax-causing bacteria. While anthrax is well-characterized in mammals, its transmission by insects points to an unidentified anthrax-resistance mechanism in its vectors. In mammals, a secreted anthrax toxin component, 83 kDa Protective Antigen (PA83), binds to cell-surface receptors and is cleaved by furin into an evolutionary-conserved PA20 and a pore-forming PA63 subunits. We show that PA20 increases the resistance of Drosophila flies and Culex mosquitoes to bacterial challenges, without directly affecting the bacterial growth. We further show that the PA83 loop known to be cleaved by furin to release PA20 from PA63 is, in part, responsible for the PA20-mediated protection. We found that PA20 binds directly to the Toll activating peptidoglycan-recognition protein-SA (PGRP-SA) and that the Toll/NF-κB pathway is necessary for the PA20-mediated protection of infected flies. This effect of PA20 on innate immunity may also exist in mammals: we show that PA20 binds to human PGRP-SA ortholog. Moreover, the constitutive activity of Imd/NF-κB pathway in MAPKK Dsor1 mutant flies is sufficient to confer the protection from bacterial infections in a manner that is independent of PA20 treatment. Lastly, Clostridium septicum alpha toxin protects flies from anthrax-causing bacteria, showing that other pathogens may help insects resist anthrax. The mechanism of anthrax resistance in insects has direct implications on insect-mediated anthrax transmission for wildlife management, and with potential for applications, such as reducing the sensitivity of pollinating insects to bacterial pathogens.


Assuntos
Vacinas contra Antraz/administração & dosagem , Antraz/tratamento farmacológico , Antígenos de Bactérias/administração & dosagem , Bacillus anthracis/efeitos dos fármacos , Toxinas Bacterianas/administração & dosagem , Drosophila melanogaster/crescimento & desenvolvimento , Mosquitos Vetores/microbiologia , Substâncias Protetoras/administração & dosagem , Animais , Antraz/microbiologia , Culex , Drosophila melanogaster/imunologia , Drosophila melanogaster/microbiologia , Feminino , Masculino
5.
MMWR Morb Mortal Wkly Rep ; 70(49): 1691-1699, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34882653

RESUMO

As of May 1, 2016, use of oral poliovirus vaccine (OPV) type 2 for routine and supplementary immunization activities ceased after a synchronized global switch from trivalent OPV (tOPV; containing Sabin strain types 1, 2, and 3) to bivalent OPV (bOPV; containing Sabin strain types 1 and 3) subsequent to the certified eradication of wild type poliovirus (WPV) type 2 in 2015 (1-3). Circulating vaccine-derived poliovirus (cVDPV) outbreaks* occur when transmission of Sabin strain poliovirus is prolonged in underimmunized populations, allowing viral genetic reversion to neurovirulence, resulting in cases of paralytic polio (1-3). Since the switch, monovalent OPV type 2 (mOPV2, containing Sabin strain type 2) has been used for response to cVDPV type 2 (cVDPV2) outbreaks; tOPV is used if cVDPV2 co-circulates with WPV type 1, and bOPV is used for cVDPV type 1 (cVDPV1) or type 3 (cVDPV3) outbreaks (1-4). In November 2020, the World Health Organization (WHO) Emergency Use Listing procedure authorized limited use of type 2 novel OPV (nOPV2), a vaccine modified to be more genetically stable than the Sabin strain, for cVDPV2 outbreak response (3,5). In October 2021, the Strategic Advisory Group of Experts on Immunization (WHO's principal advisory group) permitted wider use of nOPV2; however, current nOPV2 supply is limited (6). This report updates that of July 2019-February 2020 to describe global cVDPV outbreaks during January 2020-June 2021 (as of November 9, 2021)† (3). During this period, there were 44 cVDPV outbreaks of the three serotypes affecting 37 countries. The number of cVDPV2 cases increased from 366 in 2019 to 1,078 in 2020 (7). A goal of the Global Polio Eradication Initiative's (GPEI) 2022-2026 Strategic Plan is to better address the challenges to early CVDPV2 outbreak detection and initiate prompt and high coverage outbreak responses with available type 2 OPV to interrupt transmission by the end of 2023 (8).


Assuntos
Surtos de Doenças/estatística & dados numéricos , Saúde Global/estatística & dados numéricos , Poliomielite/epidemiologia , Vacina Antipólio Oral/efeitos adversos , Poliovirus/isolamento & purificação , Humanos , Poliomielite/etiologia , Poliomielite/prevenção & controle , Poliovirus/classificação , Vacina Antipólio Oral/administração & dosagem , Sorotipagem
6.
Nucleic Acids Res ; 47(3): 1225-1238, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30462309

RESUMO

Aberrant isoform expression of chromatin-associated proteins can induce epigenetic programs related to disease. The MDS1 and EVI1 complex locus (MECOM) encodes PRDM3, a protein with an N-terminal PR-SET domain, as well as a shorter isoform, EVI1, lacking the N-terminus containing the PR-SET domain (ΔPR). Imbalanced expression of MECOM isoforms is observed in multiple malignancies, implicating EVI1 as an oncogene, while PRDM3 has been suggested to function as a tumor suppressor through an unknown mechanism. To elucidate functional characteristics of these N-terminal residues, we compared the protein interactomes of the full-length and ΔPR isoforms of PRDM3 and its closely related paralog, PRDM16. Unlike the ΔPR isoforms, both full-length isoforms exhibited a significantly enriched association with components of the NuRD chromatin remodeling complex, especially RBBP4. Typically, RBBP4 facilitates chromatin association of the NuRD complex by binding to histone H3 tails. We show that RBBP4 binds to the N-terminal amino acid residues of PRDM3 and PRDM16, with a dissociation constant of 3.0 µM, as measured by isothermal titration calorimetry. Furthermore, high-resolution X-ray crystal structures of PRDM3 and PRDM16 N-terminal peptides in complex with RBBP4 revealed binding to RBBP4 within the conserved histone H3-binding groove. These data support a mechanism of isoform-specific interaction of PRDM3 and PRDM16 with the NuRD chromatin remodeling complex.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteína do Locus do Complexo MDS1 e EVI1/química , Proteína do Locus do Complexo MDS1 e EVI1/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular , Cristalografia por Raios X , Humanos , Proteína do Locus do Complexo MDS1 e EVI1/genética , Camundongos , Modelos Moleculares , Neoplasias/genética , Neoplasias/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteína 4 de Ligação ao Retinoblastoma/química , Proteína 4 de Ligação ao Retinoblastoma/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
7.
Virol J ; 17(1): 43, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32234060

RESUMO

BACKGROUND: Zika virus (ZIKV) is a major human pathogen and member of the Flavivirus genus. Previous studies have identified neutralizing antibodies from Zika patients that bind to quaternary epitopes across neighboring envelope (E) proteins, called E dimer epitopes (EDE). An asparagine-linked glycan on the "glycan loop" (GL) of the ZIKV envelope protein protects the functionally important "fusion loop" on the opposite E subunit in the dimer, and EDE antibodies have been shown to bind to both of these loops. Human EDE antibodies have been divided into two subclasses based on how they bind to the glycan loop region: EDE1 antibodies do not require glycosylation for binding, while EDE2 antibodies strongly rely on the glycan for binding. METHODS: ZIKV GL was expressed on tobacco mosaic virus nanoparticles. Mice were immunized with GL or full-length monomeric E and the immune response was analyzed by testing the ability of sera and monoclonal antibodies to bind to GL and to neutralize ZIKV in in vitro cellular assay. RESULTS: We report here the existence of ZIKV moderately neutralizing antibodies that bind to E monomers through epitopes that include the glycan loop. We show that sera from human Zika patients contain antibodies capable of binding to the unglycosylated glycan loop in the absence of the rest of the envelope protein. Furthermore, mice were inoculated with recombinant E monomers and produced neutralizing antibodies that either recognize unglycosylated glycan loop or require glycan for their binding to monomeric E. We demonstrate that both types of antibodies neutralize ZIKV to some extent in a cellular virus neutralization assay. CONCLUSIONS: Analogous to the existing EDE antibody nomenclature, we propose a new classification for antibodies that bind to E monomer epitopes (EME): EME1 and EME2 for those that do not require and those that do require glycan for binding to E, respectively.


Assuntos
Anticorpos Antivirais/imunologia , Polissacarídeos/imunologia , Proteínas do Envelope Viral/imunologia , Zika virus/química , Zika virus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sítios de Ligação de Anticorpos , Epitopos/imunologia , Feminino , Glicosilação , Humanos , Imunogenicidade da Vacina , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Testes de Neutralização , Polissacarídeos/genética , Vírus do Mosaico do Tabaco/genética , Infecção por Zika virus/virologia
8.
MMWR Morb Mortal Wkly Rep ; 69(20): 623-629, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32437342

RESUMO

Since the Global Polio Eradication Initiative (GPEI) was launched in 1988, the number of polio cases worldwide has declined approximately 99.99%; only two countries (Afghanistan and Pakistan) have never interrupted wild poliovirus (WPV) transmission (1). The primary means of detecting poliovirus circulation is through surveillance for acute flaccid paralysis (AFP) among children aged <15 years with testing of stool specimens for WPV and vaccine-derived polioviruses (VDPVs) (genetically reverted strains of the vaccine virus that regain neurovirulence) in World Health Organization (WHO)-accredited laboratories (2,3). In many locations, AFP surveillance is supplemented by environmental surveillance, the regular collection and testing of sewage to provide awareness of the extent and duration of poliovirus circulation (3). This report presents 2018-2019 poliovirus surveillance data, focusing on 40 priority countries* with WPV or VDPV outbreaks or at high risk for importation because of their proximity to a country with an outbreak. The number of priority countries rose from 31 in 2018 to 40 in 2019 because of a substantial increase in the number of VDPV outbreaks† (2,4). In areas with low poliovirus immunity, VDPVs can circulate in the community and cause outbreaks of paralysis; these are known as circulating vaccine derived polioviruses (cVDPVs) (4). In 2019, only 25 (63%) of the 40 designated priority countries met AFP surveillance indicators nationally; subnational surveillance performance varied widely and indicated focal weaknesses. High quality, sensitive surveillance is important to ensure timely detection and response to cVDPV and WPV transmission.


Assuntos
Erradicação de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/prevenção & controle , Vigilância da População , Monitoramento Ambiental , Humanos , Laboratórios , Paralisia/epidemiologia , Poliomielite/epidemiologia , Poliovirus/isolamento & purificação
9.
J Virol ; 92(9)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29444940

RESUMO

We followed the dynamics of capsid amino acid replacement among 403 Nigerian outbreak isolates of type 2 circulating vaccine-derived poliovirus (cVDPV2) from 2005 through 2011. Four different functional domains were analyzed: (i) neutralizing antigenic (NAg) sites, (ii) residues binding the poliovirus receptor (PVR), (iii) VP1 residues 1 to 32, and (iv) the capsid structural core. Amino acid replacements mapped to 37 of 43 positions across all 4 NAg sites; the most variable and polymorphic residues were in NAg sites 2 and 3b. The most divergent of the 120 NAg variants had no more than 5 replacements in all NAg sites and were still neutralized at titers similar to those of Sabin 2. PVR-binding residues were less variable (25 different variants; 0 to 2 replacements per isolate; 30/44 invariant positions), with the most variable residues also forming parts of NAg sites 2 and 3a. Residues 1 to 32 of VP1 were highly variable (133 different variants; 0 to 6 replacements per isolate; 5/32 invariant positions), with residues 1 to 18 predicted to form a well-conserved amphipathic helix. Replacement events were dated by mapping them onto the branches of time-scaled phylogenies. Rates of amino acid replacement varied widely across positions and followed no simple substitution model. Replacements in the structural core were the most conservative and were fixed at an overall rate ∼20-fold lower than the rates for the NAg sites and VP1 1 to 32 and ∼5-fold lower than the rate for the PVR-binding sites. Only VP1 143-Ile, a non-NAg site surface residue and known attenuation site, appeared to be under strong negative selection.IMPORTANCE The high rate of poliovirus evolution is offset by strong selection against amino acid replacement at most positions of the capsid. Consequently, poliovirus vaccines developed from strains isolated decades ago have been used worldwide to bring wild polioviruses almost to extinction. The apparent antigenic stability of poliovirus obscures a dynamic of continuous change within the neutralizing antigenic (NAg) sites. During 7 years of a large outbreak in Nigeria, the circulating type 2 vaccine-derived polioviruses generated 120 different NAg site variants via multiple independent pathways. Nonetheless, overall antigenic evolution was constrained, as no isolate had fixed more than 5 amino acid differences from the Sabin 2 NAg sites, and the most divergent isolates were efficiently neutralized by human immune sera. Evolution elsewhere in the capsid was also constrained. Amino acids binding the poliovirus receptor were strongly conserved, and extensive variation in the VP1 amino terminus still conserved a predicted amphipathic helix.


Assuntos
Anticorpos Neutralizantes/imunologia , Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Capsídeo/imunologia , Surtos de Doenças , Poliomielite/imunologia , Poliovirus/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Pré-Escolar , Epitopos/genética , Epitopos/imunologia , Humanos , Lactente , Filogenia , Poliomielite/virologia
10.
MMWR Morb Mortal Wkly Rep ; 68(45): 1024-1028, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31725706

RESUMO

Certification of global eradication of indigenous wild poliovirus type 2 occurred in 2015 and of type 3 in 2019. Since the launch of the Global Polio Eradication Initiative (GPEI) in 1988 and broad use of live, attenuated oral poliovirus vaccine (OPV), the number of wild poliovirus cases has declined >99.99% (1). Genetically divergent vaccine-derived poliovirus* (VDPV) strains can emerge during vaccine use and spread in underimmunized populations, becoming circulating VDPV (cVDPV) strains, and resulting in outbreaks of paralytic poliomyelitis.† In April 2016, all oral polio vaccination switched from trivalent OPV (tOPV; containing vaccine virus types 1, 2, and 3) to bivalent OPV (bOPV; containing types 1 and 3) (2). Monovalent type 2 OPV (mOPV2) is used in response campaigns to control type 2 cVDPV (cVDPV2) outbreaks. This report presents data on cVDPV outbreaks detected during January 2018-June 2019 (as of September 30, 2019). Compared with January 2017-June 2018 (3), the number of reported cVDPV outbreaks more than tripled, from nine to 29; 25 (86%) of the outbreaks were caused by cVDPV2. The increase in the number of outbreaks in 2019 resulted from VDPV2 both inside and outside of mOPV2 response areas. GPEI is planning future use of a novel type 2 OPV, stabilized to decrease the likelihood of reversion to neurovirulence. However, all countries must maintain high population immunity to decrease the risk for cVDPV emergence. Cessation of all OPV use after certification of polio eradication will eliminate the risk for VDPV emergence.


Assuntos
Surtos de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/epidemiologia , Vacina Antipólio Oral/efeitos adversos , Poliovirus/isolamento & purificação , Humanos , Poliomielite/etiologia , Poliomielite/prevenção & controle , Poliovirus/classificação , Vacina Antipólio Oral/administração & dosagem , Sorotipagem
11.
Int J Hyperthermia ; 36(1): 712-720, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31345068

RESUMO

Purpose: A proposed mechanism for the enhanced effectiveness of hyperthermia and doxorubicin (Dox) combinations is increased intracellular Dox concentrations resulting from heat-induced cell stress. The purpose of this study was to determine whether specific varied Dox and heat combinations produce measurable effects greater than the additive combination, and whether these effects can be attributed to heat-induced increases in intracellular Dox concentrations. Methods: HCT116, HT29 and CT26 cells were exposed to Dox and water bath heating independently. A clonogenic survival assay was used to determine cell killing and intracellular Dox concentrations were measured in HCT116 cells with mass spectrometry. Cells were exposed to heating at 42 °C (60 min) and 0.5 µg/ml of Dox at varying intervals. Synergy was determined by curve-fitting and isobologram analysis. Results: All cell lines displayed synergistic effects of combined heating and Dox. A maximum synergistic effect was achieved with simultaneous cell exposure to Dox and heat. For exposures at 42 °C, the synergistic effect was most pronounced at Dox concentrations <0.5 µg/ml. Increased intracellular concentrations of Dox in HCT116 cells caused by heat-stress did not generate a concomitant thermal enhancement. Conclusions: Simultaneous exposure of HCT116 cells to heating and Dox is more effective than sequential exposure. Heat-induced cell responses are accompanied by increased intracellular Dox concentrations; however, clonogenic survival data do not support this as the cause for synergistic cytotoxicity.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Temperatura Alta , Transporte Biológico , Morte Celular , Linhagem Celular Tumoral , Humanos
12.
BMC Bioinformatics ; 19(Suppl 11): 364, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30343671

RESUMO

BACKGROUND: Determining patterns of nucleotide and amino acid substitution is the first step during sequence evolution analysis. However, it is not easy to visualize the different phylogenetic signatures imprinted in aligned nucleotide and amino acid sequences. RESULTS: Here we present PoSE (Pattern of Sequence Evolution), a reliable resource for unveiling the evolutionary history of sequence alignments and for graphically displaying their contents. Substitutions are displayed by category (transitions and transversions), codon position, and phenotypic effect (synonymous and nonsynonymous). Visualization is accomplished using MATLAB scripts wrapped around PAML (Phylogenetic Analysis by Maximum Likelihood), implemented in an easy-to-use graphical user interface. The application displays inferred substitutions estimated by baseml or codeml, two programs included in the PAML software package. PoSE organizes patterns of substitution in eleven plots, including estimated non-synonymous/synonymous ratios (dN/dS) along the sequence alignment. In addition, PoSE provides visualization and annotation of patterns of amino acid substitutions along groups of related sequences that can be graphically inspected in a phylogenetic tree window. CONCLUSIONS: PoSE is a useful tool to help determine major patterns during sequence evolution of protein-coding sequences, hypervariable regions, or changes in dN/dS ratios. PoSE is publicly available at https://github.com/CDCgov/PoSE.


Assuntos
Evolução Molecular , Software , Pareamento de Bases/genética , Sequência de Bases , Códon/genética , Filogenia , Poliovirus/genética
13.
Br J Cancer ; 119(2): 220-229, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29991697

RESUMO

BACKGROUND: Immunohistochemistry (IHC) is often used in personalisation of cancer treatments. Analysis of large data sets to uncover predictive biomarkers by specialists can be enormously time-consuming. Here we investigated crowdsourcing as a means of reliably analysing immunostained cancer samples to discover biomarkers predictive of cancer survival. METHODS: We crowdsourced the analysis of bladder cancer TMA core samples through the smartphone app 'Reverse the Odds'. Scores from members of the public were pooled and compared to a gold standard set scored by appropriate specialists. We also used crowdsourced scores to assess associations with disease-specific survival. RESULTS: Data were collected over 721 days, with 4,744,339 classifications performed. The average time per classification was approximately 15 s, with approximately 20,000 h total non-gaming time contributed. The correlation between crowdsourced and expert H-scores (staining intensity × proportion) varied from 0.65 to 0.92 across the markers tested, with six of 10 correlation coefficients at least 0.80. At least two markers (MRE11 and CK20) were significantly associated with survival in patients with bladder cancer, and a further three markers showed results warranting expert follow-up. CONCLUSIONS: Crowdsourcing through a smartphone app has the potential to accurately screen IHC data and greatly increase the speed of biomarker discovery.


Assuntos
Biomarcadores Tumorais/genética , Telefone Celular , Crowdsourcing , Neoplasias da Bexiga Urinária/diagnóstico , Feminino , Humanos , Imuno-Histoquímica , Queratina-20/genética , Proteína Homóloga a MRE11/genética , Masculino , Pessoa de Meia-Idade , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
14.
MMWR Morb Mortal Wkly Rep ; 67(42): 1189-1194, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30359342

RESUMO

Since the Global Polio Eradication Initiative was launched in 1988 (1), the number of polio cases worldwide has declined by >99.99%. Among the three wild poliovirus (WPV) serotypes, only type 1 (WPV1) has been detected since 2012. This decline is attributable primarily to use of the live, attenuated oral poliovirus vaccine (OPV) in national routine immunization schedules and mass vaccination campaigns. The success and safety record of OPV use is offset by the rare emergence of genetically divergent vaccine-derived polioviruses (VDPVs), whose genetic drift from the parental OPV strains indicates prolonged replication or circulation (2). Circulating VDPVs (cVDPVs) can emerge in areas with low immunization coverage and can cause outbreaks of paralytic polio. In addition, immunodeficiency-associated VDPVs (iVDPVs) can emerge in persons with primary immunodeficiencies and can replicate and be excreted for years. This report presents data on VDPVs detected during January 2017-June 2018 and updates previous VDPV summaries (3). During this reporting period, new cVDPV outbreaks were detected in five countries. Fourteen newly identified persons in nine countries were found to excrete iVDPVs. Ambiguous VDPVs (aVDPVs), isolates that cannot be classified definitively, were found among immunocompetent persons and environmental samples in seven countries.


Assuntos
Surtos de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/epidemiologia , Vacina Antipólio Oral/efeitos adversos , Poliovirus/isolamento & purificação , Humanos , Poliomielite/etiologia , Poliomielite/prevenção & controle , Poliovirus/classificação , Poliovirus/genética , Vacina Antipólio Oral/administração & dosagem , Sorotipagem
16.
Nurs Outlook ; 66(2): 121-129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29525131

RESUMO

BACKGROUND: The Center for Technology in Support of Self-Management and Health (NUCare) is an exploratory research center funded by the National Institute of Nursing Research's P20 mechanism positioned to conduct rigorous research on the integration of technology in the self-management of the older adult population. PURPOSE: The purpose of this paper is to describe the development and application of an evaluation plan and preliminary evaluation results from the first year of implementation. METHODS: This evaluation plan is derived from and is consistent with Dorsey et al.'s (2014) logic model. Dorsey's model provided guidelines for evaluating sustainability, leveraging of resources, and interdisciplinary collaboration within the center. DISCUSSION: Preliminary results and strategies for addressing findings from the first year of evaluation are discussed. A secondary aim of this paper is to showcase the relevance of this center to the advancement and maintenance of health in the aging population.


Assuntos
Envelhecimento , Pesquisa em Enfermagem/organização & administração , Autogestão , Comitês Consultivos , Docentes de Enfermagem , Humanos , National Institute of Nursing Research (U.S.) , Projetos Piloto , Dinâmica Populacional , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários , Estados Unidos
17.
J Clin Microbiol ; 55(2): 606-615, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27927929

RESUMO

The poliovirus (PV) is currently targeted for worldwide eradication and containment. Sanger-based sequencing of the viral protein 1 (VP1) capsid region is currently the standard method for PV surveillance. However, the whole-genome sequence is sometimes needed for higher resolution global surveillance. In this study, we optimized whole-genome sequencing protocols for poliovirus isolates and FTA cards using next-generation sequencing (NGS), aiming for high sequence coverage, efficiency, and throughput. We found that DNase treatment of poliovirus RNA followed by random reverse transcription (RT), amplification, and the use of the Nextera XT DNA library preparation kit produced significantly better results than other preparations. The average viral reads per total reads, a measurement of efficiency, was as high as 84.2% ± 15.6%. PV genomes covering >99 to 100% of the reference length were obtained and validated with Sanger sequencing. A total of 52 PV genomes were generated, multiplexing as many as 64 samples in a single Illumina MiSeq run. This high-throughput, sequence-independent NGS approach facilitated the detection of a diverse range of PVs, especially for those in vaccine-derived polioviruses (VDPV), circulating VDPV, or immunodeficiency-related VDPV. In contrast to results from previous studies on other viruses, our results showed that filtration and nuclease treatment did not discernibly increase the sequencing efficiency of PV isolates. However, DNase treatment after nucleic acid extraction to remove host DNA significantly improved the sequencing results. This NGS method has been successfully implemented to generate PV genomes for molecular epidemiology of the most recent PV isolates. Additionally, the ability to obtain full PV genomes from FTA cards will aid in facilitating global poliovirus surveillance.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Poliovirus/classificação , Poliovirus/genética , Manejo de Espécimes/métodos , Humanos , Epidemiologia Molecular/métodos , Projetos Piloto
18.
MMWR Morb Mortal Wkly Rep ; 66(43): 1185-1191, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29095803

RESUMO

In 1988, the World Health Assembly launched the Global Polio Eradication Initiative (GPEI) (1). Among the three wild poliovirus (WPV) serotypes, only type 1 (WPV1) has been detected since 2012. Since 2014, detection of WPV1 has been limited to three countries, with 37 cases in 2016 and 11 cases in 2017 as of September 27. The >99.99% decline worldwide in polio cases since the launch of the GPEI is attributable to the extensive use of the live, attenuated oral poliovirus vaccine (OPV) in mass vaccination campaigns and comprehensive national routine immunization programs. Despite its well-established safety record, OPV use can be associated with rare emergence of genetically divergent vaccine-derived polioviruses (VDPVs) whose genetic drift from the parental OPV strains indicates prolonged replication or circulation (2). VDPVs can also emerge among persons with primary immunodeficiencies (PIDs). Immunodeficiency-associated VDPVs (iVDPVs) can replicate for years in some persons with PIDs. In addition, circulating vaccine-derived polioviruses (cVDPVs) can emerge very rarely among immunologically normal vaccine recipients and their contacts in areas with inadequate OPV coverage and can cause outbreaks of paralytic polio. This report updates previous summaries regarding VDPVs (3). During January 2016-June 2017, new cVDPV outbreaks were identified, including two in the Democratic Republic of the Congo (DRC) (eight cases), and another in Syria (35 cases), whereas the circulation of cVDPV type 2 (cVDPV2) in Nigeria resulted in cVDPV2 detection linked to a previous emergence. The last confirmed case from the 2015-2016 cVDPV type 1 (cVDPV1) outbreak in Laos occurred in January 2016. Fourteen newly identified persons in 10 countries were found to excrete iVDPVs, and three previously reported patients in the United Kingdom and Iran (3) were still excreting type 2 iVDPV (iVDPV2) during the reporting period. Ambiguous VDPVs (aVDPVs), isolates that cannot be classified definitively, were found among immunocompetent persons and environmental samples in 10 countries. Cessation of all OPV use after certification of polio eradication will eliminate the risk for new VDPV infections.


Assuntos
Surtos de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/epidemiologia , Vacina Antipólio Oral/efeitos adversos , Poliovirus/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Hospedeiro Imunocomprometido , Lactente , Masculino , Poliomielite/etiologia , Poliomielite/prevenção & controle , Poliovirus/classificação , Poliovirus/genética , Vacina Antipólio Oral/administração & dosagem , Sorotipagem , Esgotos/virologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos
19.
Can J Infect Dis Med Microbiol ; 2016: 2935870, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27375749

RESUMO

Background. Electronic surveillance systems (ESSs) that utilize existing information in databases are more efficient than conventional infection surveillance methods. The objective was to assess an ESS for bloodstream infections (BSIs) in the Calgary Zone for its agreement with traditional medical record review. Methods. The ESS was developed by linking related data from regional laboratory and hospital administrative databases and using set definitions for excluding contaminants and duplicate isolates. Infections were classified as hospital-acquired (HA), healthcare-associated community-onset (HCA), or community-acquired (CA). A random sample of patients from the ESS was then compared with independent medical record review. Results. Among the 308 patients selected for comparative review, the ESS identified 318 episodes of BSI of which 130 (40.9%) were CA, 98 (30.8%) were HCA, and 90 (28.3%) were HA. Medical record review identified 313 episodes of which 136 (43.4%) were CA, 97 (30.9%) were HCA, and 80 (25.6%) were HA. Episodes of BSI were concordant in 304 (97%) cases. Overall, there was 85.5% agreement between ESS and medical record review for the classification of where BSIs were acquired (kappa = 0.78, 95% Confidence Interval: 0.75-0.80). Conclusion. This novel ESS identified and classified BSIs with a high degree of accuracy. This system requires additional linkages with other related databases.

20.
Artigo em Inglês | MEDLINE | ID: mdl-26015790

RESUMO

BACKGROUND: Increasing antimicrobial resistance has been identified as an important global health threat. Antimicrobial use is a major driver of resistance, especially in the hospital sector. Understanding the extent and type of antimicrobial use in Canadian hospitals will aid in developing national antimicrobial stewardship priorities. METHODS: In 2002 and 2009, as part of one-day prevalence surveys to quantify hospital-acquired infections in Canadian Nosocomial Infection Surveillance Program hospitals, data were collected on the use of systemic antimicrobial agents in all patients in participating hospitals. Specific agents in use (other than antiviral and antiparasitic agents) on the survey day and patient demographic information were collected. RESULTS: In 2002, 2460 of 6747 patients (36.5%) in 28 hospitals were receiving antimicrobial therapy. In 2009, 3989 of 9953 (40.1%) patients in 44 hospitals were receiving antimicrobial therapy (P<0.001). Significantly increased use was observed in central Canada (37.4% to 40.8%) and western Canada (36.9% to 41.1%) but not in eastern Canada (32.9% to 34.1%). In 2009, antimicrobial use was most common on solid organ transplant units (71.0% of patients), intensive care units (68.3%) and hematology/oncology units (65.9%). Compared with 2002, there was a significant decrease in use of first-and second-generation cephalosporins, and significant increases in use of carbapenems, antifungal agents and vancomycin in 2009. Piperacillin-tazobactam, as a proportion of all penicillins, increased from 20% in 2002 to 42.8% in 2009 (P<0.001). There was a significant increase in simultaneous use of >1 agent, from 12.0% of patients in 2002 to 37.7% in 2009. CONCLUSION: From 2002 to 2009, the prevalence of antimicrobial agent use in Canadian Nosocomial Infection Surveillance Program hospitals significantly increased; additionally, increased use of broad-spectrum agents and a marked increase in simultaneous use of multiple agents were observed.


HISTORIQUE: La résistance antimicrobienne croissante est une menace importante pour la santé dans le monde. L'utilisation d'antimicrobiens est un moteur de résistance majeur, particulièrement dans le milieu hospitalier. Il faut comprendre la portée et le type d'utilisation des antimicrobiens dans les hôpitaux canadiens pour établir les priorités nationales en matière de gouvernance antimicrobienne. MÉTHODOLOGIE: En 2002 et 2009, dans le cadre de sondages de prévalence d'une journée visant à quantifier les infections nosocomiales dans les hôpitaux du Programme canadien de surveillance des infections nosocomiales, les chercheurs ont colligé des données sur l'utilisation des antimicrobiens systémiques par tous les patients des hôpitaux participants. Le jour du sondage, ils ont recueilli les agents précis utilisés (à part les antiviraux et les antiparasitaires) et l'information démographique relative aux patients. RÉSULTATS: En 2002, 2 460 des 6 747 patients (36,5 %) de 28 hôpitaux recevaient un traitement antimicrobien. En 2009, 3 989 des 9 953 patients (40,1 %) de 44 hôpitaux recevaient un tel traitement (P<0,001). L'utilisation avait beaucoup augmenté au centre du Canada (37,4 % à 40,8 %) et dans l'Ouest canadien (36,9 % à 41,1 %), mais pas dans l'Est canadien (32,9 % à 34,1 %). En 2009, l'utilisation d'antimicrobiens était plus courante dans les unités de transplantation d'organes pleins (71,0 % des patients), les unités de soins intensifs (68,3 %) et les unités d'hématologie-oncologie (65,9 %). Par rapport à 2002, on constatait en 2009 une diminution importante des céphalosporines de première et seconde générations et des augmentations marquées de carbapénèmes, d'antifongiques et de vancomycine. L'utilisation de piperacilline-tazobactam, en proportion de toutes les pénicillines, est passée de 20 % en 2002 à 42,8 % en 2009 (P<0,001). L'utilisation simultanée de plus d'un agent a également connu une hausse importante, passant de 12,0 % des patients en 2002 à 37,7 % en 2009. CONCLUSION: De 2002 à 2009, la prévalence d'utilisation d'antimicrobiens dans les hôpitaux du Programme canadien de surveillance des infections nosocomiales a considérablement augmenté. De plus, les chercheurs ont constaté une augmentation marquée d'agents à large spectre et d'utilisation simultanée de multiples agents.

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