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1.
Spec Care Dentist ; 41(2): 251-270, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33438306

RESUMO

AIM: The objective of this systematic review was to evaluate the efficacy of denture adhesives (DAs) in completely edentulous denture wearers compared to not using DAs. METHODS AND RESULTS: PubMed, Web of Science, Cochrane Library, and EMBASE were searched from the database inception up to 6 February 2020 for Randomized Controlled Trials (RCTs) involving patients with complete dentures in both arches where the use of DAs was compared to no use of DAs. A total of 497 abstracts were reviewed, resulting in inclusion of 10 RCTs. Outcomes reported in the included trials were thoroughly reviewed and tabulated. The Cochrane risk of bias tool was used. All 10 studies were assessed at unclear (10%) or high risk of bias (90%). Studies showed DAs improved mainly retention/stability, and masticatory/chewing ability/performance, compared to no adhesives. CONCLUSION: Most studies showed favorable results for DAs on retention and stability of complete dentures, masticatory performance, patient's comfort and satisfaction. Due to the heterogeneity of the outcomes, unclear/high risk of bias and small sample sizes, the quality of the evidence was very low. More high-quality research is needed with improved blinding and use of standardized methods to evaluate the efficacy of DAs.


Assuntos
Cimentos Dentários , Boca Edêntula , Prótese Total , Humanos , Mastigação , Satisfação do Paciente
2.
J Transl Med ; 16(1): 291, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30355298

RESUMO

BACKGROUND: Successful delivery of cell-based therapeutics into patients is compromised by their short shelf-life upon release from production facilities due to the living nature of the active component that rapidly loses viability, and therefore its properties. In this context, the use of appropriate additives may contribute to the stabilisation of the cellular component within specifications for a longer time until administration. RESULTS: In the present study, we evaluated the effect of different formulations on the stability of viability, identity, and potency of clinical grade multipotent mesenchymal stromal cells in suspension, both electrolyte solution and protein content were found to impact on their shelf-life. Particularly cryopreservation of cells in a Plasmalyte 148 supplemented with 2% (w/v) AlbIX (a yeast-derived recombinant albumin) and 10% (v/v) dimethyl sulfoxide, and final formulation post-thawing in Plasmalyte 148 supplemented with 2% (w/v) AlbIX enabling prolonged stability from 24 h up to 72 h in optimal conditions. Further investigation on the mechanisms of action involved revealed a delay of apoptosis progression into late stage when AlbIX was present. CONCLUSIONS: The use of optimal formulations for each cell type of interest is crucial to extend the shelf life of cell-based pharmaceuticals and contribute to solve logistical challenges. We demonstrated that the use of Plasmalyte 148 supplemented with 2% (w/v) AlbIX resulted in superior stability of multipotent mesenchymal stromal cells without affecting their identity and multipotency.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Criopreservação , Crioprotetores/farmacologia , Eletrólitos , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Multipotentes/metabolismo , Fenótipo , Albumina Sérica Humana/metabolismo , Soluções , Células Estromais/citologia
3.
Glob Chang Biol ; 23(2): 708-718, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27474788

RESUMO

Understanding the evolutionary consequences of the green revolution, particularly in wild populations, is an important frontier in contemporary biology. Because human impacts have occurred at varying magnitudes or time periods depending on the study ecosystem, evolutionary histories may vary considerably among populations. Paleogenetics in conjunction with paleolimnology enable us to associate microevolutionary dynamics with detailed information on environmental change. We used this approach to reconstruct changes in the temporal population genetic structure of the keystone zooplankton grazer, Daphnia pulicaria, using dormant eggs extracted from sediments in two Minnesota lakes (South Center, Hill). The extent of agriculture and human population density in the catchment of these lakes has differed markedly since European settlement in the late 19th century and is reflected in their environmental histories reconstructed here. The reconstructed environments of these two lakes differed strongly in terms of environmental stability and their associated patterns of Daphnia population structure. We detected long periods of stability in population structure and environmental conditions in South Center Lake that were followed by a dramatic temporal shift in population genetic structure after the onset of European settlement and industrialized agriculture in its watershed. In particular, we noted a 24.3-fold increase in phosphorus (P) flux between pre-European and modern sediment P accumulation rates (AR) in this lake. In contrast, no such shifts were detected in Hill Lake, where the watershed was not as impacted by European settlement and rates of change were less directional with a much smaller increase in sediment P AR (2.3-fold). We identify direct and indirect effects of eutrophication proxies on genetic structure in these lake populations and demonstrate the power of using this approach in understanding the consequences of anthropogenic environmental change on natural populations throughout historic time periods.


Assuntos
Daphnia/genética , Eutrofização , Genética Populacional , Animais , Fósseis , Humanos , Lagos , Fósforo , Pulicaria , Estados Unidos
4.
Int J Evol Biol ; 2015: 538918, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25893130

RESUMO

Understanding the mechanisms that drive acid-base regulation in organisms is important, especially for organisms in aquatic habitats that experience rapidly fluctuating pH conditions. Previous studies have shown that carbonic anhydrases (CAs), a family of zinc metalloenzymes, are responsible for acid-base regulation in many organisms. Through the use of phylogenetic tools, this present study attempts to elucidate the evolutionary history of the α-CA superfamily, with particular interest in the emerging model aquatic organism Daphnia pulex. We provide one of the most extensive phylogenies of the evolution of α-CAs, with the inclusion of 261 amino acid sequences across taxa ranging from Cnidarians to Homo sapiens. While the phylogeny supports most of our previous understanding on the relationship of how α-CAs have evolved, we find that, contrary to expectations, amino acid conservation with bacterial α-CAs supports the supposition that extracellular α-CAs are the ancestral state of animal α-CAs. Furthermore, we show that two cytosolic and one GPI-anchored α-CA in Daphnia genus have homologs in sister taxa that are possible candidate genes to study for acid-base regulation. In addition, we provide further support for previous findings of a high rate of gene duplication within Daphnia genus, as compared with other organisms.

5.
Ecol Lett ; 17(3): 360-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24400978

RESUMO

For an accurate assessment of the anthropogenic impacts on evolutionary change in natural populations, we need long-term environmental, genetic and phenotypic data that predate human disturbances. Analysis of c. 1600 years of history chronicled in the sediments of South Center Lake, Minnesota, USA, revealed major environmental changes beginning c. 120 years ago coinciding with the initiation of industrialised agriculture in the catchment area. Population genetic structure, analysed using DNA from dormant eggs of the keystone aquatic herbivore, Daphnia pulicaria, suggested no change for c. 1500 years prior to striking shifts associated with anthropogenic environmental alterations. Furthermore, phenotypic assays on the oldest resurrected metazoan genotypes (potentially as old as c. 700 years) indicate significant shifts in phosphorus utilisation rates compared to younger genotypes. Younger genotypes show steeper reaction norms with high growth under high phosphorus (P), and low growth under low P, while 'ancient' genotypes show flat reaction norms, yet higher growth efficiency under low P. Using this resurrection ecology approach, environmental, genetic and phenotypic data spanning pre- and post-industrialised agricultural eras clearly reveal the evolutionary consequences of anthropogenic environmental change.


Assuntos
Evolução Biológica , Daphnia/crescimento & desenvolvimento , Daphnia/genética , Meio Ambiente , Sedimentos Geológicos/química , Fenótipo , Animais , Frequência do Gene , Genética Populacional , Genótipo , Atividades Humanas , Humanos , Lagos , Modelos Lineares , Repetições de Microssatélites/genética , Minnesota , Fósforo/análise
6.
ACS Appl Mater Interfaces ; 5(16): 7881-5, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23806171

RESUMO

Lithium-ion batteries (LIB) have been receiving extensive attention because of the high specific energy density for wide applications such as electronic vehicles, commercial mobile electronics, and military applications. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To overcome this obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown propitious results for enhanced lithium intercalation. Recently, nanowire/graphene hybrids were developed for the enhancement of LIB performance; however, almost all previous efforts employed nanowires on graphene in a random fashion, which limited lithium-ion diffusion rate. Therefore, we demonstrate a new approach by hydrothermally growing uniform nanowires on graphene aerogel to further improve the performance. This nanowire/graphene aerogel hybrid not only uses the high surface area of the graphene aerogel but also increases the specific surface area for electrode-electrolyte interaction. Therefore, this new nanowire/graphene aerogel hybrid anode material could enhance the specific capacity and charge-discharge rate. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used for materials characterization. Battery analyzer and potentio-galvanostat are used for measuring the electrical performance of the battery. The testing results show that nanowire graphene hybrid anode gives significantly improved performance compared to graphene anode.


Assuntos
Grafite/química , Lítio/química , Óxidos/química , Carbono/química , Fontes de Energia Elétrica , Eletrodos , Nanoestruturas/química , Nanofios/química , Propriedades de Superfície , Difração de Raios X
7.
PLoS One ; 8(3): e59833, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23544103

RESUMO

An integral part to understanding the biology of an invasive species is determining its origin, particularly in pest species. As one of the oldest known invasive species, the goals of this study were to evaluate the evidence of a westward expansion of Hessian fly into North America, from a potential singular introduction event, and the population genetic structure of current populations. Levels of genetic diversity and population structure in the Hessian fly were compared across North America, Europe, North Africa, Western Asia, and New Zealand. Furthermore, Old World populations were evaluated as possible sources of introduction. We tested diversity and population structure by examining 18 microsatellite loci with coverage across all four Hessian fly chromosomes. Neither genetic diversity nor population genetic structure provided evidence of a westward movement from a single introduction in North America. Introduced populations in North America did not show identity or assignment to any Old World population, likely indicating a multiple introduction scenario with subsequent gene flow between populations. Diversity and selection were assessed on a chromosomal level, with no differences in diversity or selection between chromosomes or between native and introduced populations.


Assuntos
Migração Animal , Dípteros/genética , Geografia , Espécies Introduzidas , Animais , Cromossomos de Insetos/genética , Frequência do Gene/genética , Loci Gênicos/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Nova Zelândia , América do Norte , Motivos de Nucleotídeos/genética , Dinâmica Populacional
8.
Bioorg Med Chem Lett ; 21(6): 1827-31, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21316220

RESUMO

This report describes the design and synthesis of a series of CCR2 antagonists incorporating novel non-aryl/heteroaryl RHS (right hand side) motifs. Previous SAR in the area has suggested an aryl/heteroaryl substituent as a necessary structural feature for binding to the CCR2 receptor. Herein we describe the SAR with regards to potency (binding to hCCR2), dofetilide activity and metabolic stability (in vitro HLM) for this series. The resulting outcome was the identification of compounds with excellent properties for the investigation of the role of CCR2 in disease.


Assuntos
Desenho de Fármacos , Receptores CCR2/antagonistas & inibidores , Sítios de Ligação , Modelos Moleculares , Relação Estrutura-Atividade
9.
Bioorg Med Chem Lett ; 21(9): 2626-30, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21315584

RESUMO

We describe the systematic optimization, focused on the improvement of CV-TI, of a series of CCR2 antagonists. This work resulted in the identification of 10 (((1S,3R)-1-isopropyl-3-((3S,4S)-3-methoxy-tetrahydro-2H-pyran-4-ylamino)cyclopentyl)(4-(5-(trifluoromethyl)pyridazin-3-yl)piperazin-1-yl)methanone) which possessed a low projected human dose 35-45mg BID and a CV-TI=3800-fold.


Assuntos
Anti-Inflamatórios/farmacologia , Modelos Moleculares , Piperazinas/química , Piperazinas/farmacologia , Piridazinas/química , Piridazinas/farmacologia , Receptores CCR2/agonistas , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Bioensaio , Humanos , Concentração Inibidora 50 , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Estrutura Molecular , Piperazinas/farmacocinética , Ligação Proteica/efeitos dos fármacos , Piridazinas/farmacocinética , Receptores CCR2/sangue , Relação Estrutura-Atividade
10.
ACS Med Chem Lett ; 2(12): 913-8, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-24900280

RESUMO

We report the discovery of a new (S)-3-aminopyrrolidine series of CCR2 antagonists. Structure-activity relationship studies on this new series led to the identification of 17 (INCB8761/PF-4136309) that exhibited potent CCR2 antagonistic activity, high selectivity, weak hERG activity, and an excellent in vitro and in vivo ADMET profile. INCB8761/PF-4136309 has entered human clinical trials.

11.
Environ Entomol ; 40(5): 1303-16, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22251741

RESUMO

Population structure dictates the evolution of each population, and thus, the species as a whole. Incorporating spatial variables with population genetic statistics allows for greater discovery beyond traditional population genetics alone and can inform management decisions. The understanding of population structure in Hessian fly, Mayetiola destructor (Say), a pest of wheat, has been limited in the past. We scored 14 microsatellite loci from 12 collections of Hessian fly in the southeastern United States. Through Bayesian clustering analysis, we found two major populations of Hessian fly covering the entire southeastern United States. We evaluated correlations between agriculturally significant spatial variables and population genetic differentiation to test if genetic structure has an ecological component in a wheat agro-ecosystem. Our results suggest the total amount of alternative host plants in the county may be driving some genetic differentiation. Although planting date may also be influential, geographic distance, mean annual temperature, and harvested wheat for grain do not seem to be contributing factors. The ecological or spatial component to population structure, however, may be minimal compared to factors such as genetic drift.


Assuntos
Dípteros/genética , Variação Genética , Triticum/parasitologia , Animais , Teorema de Bayes , Análise por Conglomerados , Feminino , Frequência do Gene , Masculino , Cadeias de Markov , Repetições de Microssatélites , Sudeste dos Estados Unidos
12.
Microb Cell Fact ; 9: 87, 2010 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-21083917

RESUMO

BACKGROUND: Animal-free recombinant proteins provide a safe and effective alternative to tissue or serum-derived products for both therapeutic and biomanufacturing applications. While recombinant insulin and albumin already exist to replace their human counterparts in cell culture media, until recently there has been no equivalent for serum transferrin. RESULTS: The first microbial system for the high-level secretion of a recombinant transferrin (rTf) has been developed from Saccharomyces cerevisiae strains originally engineered for the commercial production of recombinant human albumin (Novozymes' Recombumin® USP-NF) and albumin fusion proteins (Novozymes' albufuse®). A full-length non-N-linked glycosylated rTf was secreted at levels around ten-fold higher than from commonly used laboratory strains. Modification of the yeast 2 µm-based expression vector to allow overexpression of the ER chaperone, protein disulphide isomerase, further increased the secretion of rTf approximately twelve-fold in high cell density fermentation. The rTf produced was functionally equivalent to plasma-derived transferrin. CONCLUSIONS: A Saccharomyces cerevisiae expression system has enabled the cGMP manufacture of an animal-free rTf for industrial cell culture application without the risk of prion and viral contamination, and provides a high-quality platform for the development of transferrin-based therapeutics.


Assuntos
Saccharomyces cerevisiae/metabolismo , Transferrina/biossíntese , Contagem de Células , Fermentação , Glicosilação , Humanos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Transferrina/química , Transferrina/genética
13.
J Hered ; 100(6): 790-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19592640

RESUMO

Ninety-four microsatellites from enriched genomic libraries of Hessian fly (Hf, Mayetiola destructor [Say]) were localized to 170 cognate clones in an Hf bacterial artificial chromosome (BAC) library. These microsatellite-positive BAC clones were physically mapped to polytene chromosomes by fluorescent in situ hybridization. The mapped microsatellite loci can be used to study the genetic diversity and population structure of Hf.


Assuntos
Cromossomos Artificiais Bacterianos/genética , Dípteros/genética , Biblioteca Gênica , Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Animais , Sequência de Bases , Biologia Computacional , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Análise de Sequência de DNA
14.
J Insect Physiol ; 55(2): 104-11, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19026654

RESUMO

In a salivary gland transcriptomics study we identified a cDNA with a full-length open reading frame for a gene (MdesL1) encoding a lipase-like protein expressed in the salivary glands of the larval Hessian fly, Mayetiola destructor (Say). Fluorescent in situ hybridization on salivary polytenes positioned MdesL1 on the long arm of Autosome 1. BLASTp and conserved domain searches revealed the deduced amino acid sequence contained a lipase superfamily domain with similarity to lipases and phospholipases from other insects. A secretion signal peptide was identified at the amino terminus of the deduced amino acid sequence. Analysis of the transcript of MdesL1 in larval Hessian fly tissues by quantitative real-time PCR (qPCR) revealed the greatest abundance was in salivary glands. Analysis of transcript levels during development showed the greatest level was detected in feeding 1st-instar and early 2nd-instar larvae. Transcript levels increased dramatically over time in larvae feeding on susceptible wheat but were detected at low levels in larvae feeding on resistant wheat. These data suggest the protein encoded by MdesL1 is likely secreted into host-plant cells during larval feeding and could be involved in extra-oral digestion and changes in host-cell permeability or in generating a second messenger in a host-cell-signaling cascade.


Assuntos
Dípteros/genética , Expressão Gênica , Genes de Insetos/genética , Lipase/genética , Filogenia , Glândulas Salivares/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Análise por Conglomerados , Biologia Computacional , Primers do DNA/genética , Dípteros/enzimologia , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
15.
Mol Ecol Resour ; 8(6): 1360-2, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21586046

RESUMO

A microsatellite library was prepared from size-selected genomic DNA of Hessian fly (Mayetiola destructor). Approximately 81% of recovered clones hybridized with microsatellite motif-specific probes. Subsequently, 2350 clones were sequenced. Sixty-two individual flies from laboratory strains were used to test for reliability and polymorphism in 50 of the microsatellites by gel electrophoresis; 18 were further tested with capillary electrophoresis. Of these, 17 behaved as a polymorphic single locus appropriate for population analysis.

16.
J Insect Physiol ; 54(1): 146-54, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17980386

RESUMO

We report on the transcriptional patterns of a putative white (w) gene encoding an ABC-active-transporter protein during development in Hessian fly, Mayetiola destructor. The deduced amino acid sequence for the Hessian fly white showed 74-77% similarities to white/ATP-binding-cassette proteins and 52-57% similarities to scarlet/ATP-binding-cassette proteins from other dipterans. Conserved ATP-binding motifs and transmembrane alpha-helix segments were identified in the Hessian fly white protein further supporting its function as an ABC-active-transporter similar to the Drosophila white protein. Spatial analysis of transcript levels for white in larval Hessian fly tissues by quantitative real-time PCR revealed the greatest level of transcript in the Malpighian tubules, while analysis of temporal expression during development revealed the highest transcript levels in late 2nd- and early 3rd-instar larvae. Analysis of transcript levels for white in Hessian fly larvae feeding on susceptible and resistant wheat showed greater levels of the transcript in larvae feeding on resistant plants. We speculate the increased transcript level for white in larvae feeding on resistant wheat could be correlated with stress and increased Malpighian tubule activity associated with the metabolism and detoxification of toxic substrates generated either endogenously or encountered exogenously from the host plant.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Dípteros/metabolismo , Dípteros/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Túbulos de Malpighi/fisiologia , Sequência de Aminoácidos , Análise de Variância , Animais , Sequência de Bases , Análise por Conglomerados , Primers do DNA/genética , DNA Complementar/genética , Dípteros/genética , Comportamento Alimentar/fisiologia , Hibridização in Situ Fluorescente , Túbulos de Malpighi/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Triticum
18.
Biotechnol Prog ; 20(4): 1096-102, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15296435

RESUMO

Conventionally, software tools for the design of bioprocesses have provided only limited business-related information for decision-making. There is an industrial need to investigate manufacturing options and to gauge the impact of various decisions from economic as well as process perspectives. This paper describes the development and use of a tool to provide an assessment of whole flowsheets by capturing both process and business aspects. The tool is demonstrated by considering the issues concerned when making decisions between two potential flowsheets for a common product. A case study approach is used to compare the process and business benefits of a conventional process route employing packed chromatography beds and an alternative that uses expanded bed adsorption (EBA). The tool allows direct evaluation of the benefits of capital cost reduction and increased yield offered by EBA against penalties of using potentially more expensive EBA matrix with lower lifetimes. Furthermore, the tool provides the ability to gauge the process robustness of each flowsheet option.


Assuntos
Biofarmácia , Indústria Farmacêutica/organização & administração , Software , Adsorção , Modelos Teóricos
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