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Newborns exposed to birth asphyxia transiently experience deficient blood flow and a lack of oxygen, potentially inducing hypoxic-ischaemic encephalopathy and subsequent neurological damage. Immunomodulatory components in plasma may dampen these responses. Using caesarean-delivered pigs as a model, we hypothesized that dietary plasma supplementation improves brain outcomes in pigs exposed to birth asphyxia. Mild birth asphyxia was induced by temporary occlusion of the umbilical cord prior to caesarean delivery. Motor development was assessed in asphyxiated (ASP) and control (CON) piglets using neonatal arousal, physical activity and gait test parameters before euthanasia on Day 4. The ASP pigs exhibited increased plasma lactate at birth, deficient motor skills and increased glial fibrillary acidic protein levels in CSF and astrogliosis in the putamen. The expression of genes related to oxidative stress, inflammation and synaptic functions was transiently altered in the motor cortex and caudate nucleus. The number of apoptotic cells among CTIP2-positive neurons in the motor cortex and striatal medium spiny neurons was increased, and maturation of preoligodendrocytes in the internal capsule was delayed. Plasma supplementation improved gait performance in the beam test, attenuated neuronal apoptosis and affected gene expression related to neuroinflammation, neurotransmission and antioxidants (motor cortex, caudate). We present a new clinically relevant animal model of moderate birth asphyxia inducing structural and functional brain damage. The components in plasma that support brain repair remain to be identified but may represent a therapeutic potential for infants and animals after birth asphyxia.
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Animais Recém-Nascidos , Asfixia Neonatal , Encéfalo , Modelos Animais de Doenças , Animais , Suínos , Asfixia Neonatal/terapia , Encéfalo/metabolismo , Feminino , Estresse Oxidativo/fisiologia , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/metabolismo , Neurônios/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Asfixia/terapia , Gravidez , Córtex Motor/metabolismoRESUMO
Marine microorganisms encode a complex repertoire of carbohydrate-active enzymes (CAZymes) for the catabolism of algal cell wall polysaccharides. While the core enzyme cascade for degrading agar is conserved across agarolytic marine bacteria, gain of novel metabolic functions can lead to the evolutionary expansion of the gene repertoire. Here, we describe how two less-abundant GH96 α-agarases harbored in the agar-specific polysaccharide utilization locus (PUL) of Colwellia echini strain A3T facilitate the versatility of the agarolytic pathway. The cellular and molecular functions of the α-agarases examined by genomic, transcriptomic, and biochemical analyses revealed that α-agarases of C. echini A3T create a novel auxiliary pathway. α-Agarases convert even-numbered neoagarooligosaccharides to odd-numbered agaro- and neoagarooligosaccharides, providing an alternative route for the depolymerization process in the agarolytic pathway. Comparative genomic analysis of agarolytic bacteria implied that the agarolytic gene repertoire in marine bacteria has been diversified during evolution, while the essential core agarolytic gene set has been conserved. The expansion of the agarolytic gene repertoire and novel hydrolytic functions, including the elucidated molecular functionality of α-agarase, promote metabolic versatility by channeling agar metabolism through different routes. IMPORTANCEColwellia echini A3T is an example of how the gain of gene(s) can lead to the evolutionary expansion of agar-specific polysaccharide utilization loci (PUL). C. echini A3T encodes two α-agarases in addition to the core ß-agarolytic enzymes in its agarolytic PUL. Among the agar-degrading CAZymes identified so far, only a few α-agarases have been biochemically characterized. The molecular and biological functions of two α-agarases revealed that their unique hydrolytic pattern leads to the emergence of auxiliary agarolytic pathways. Through the combination of transcriptomic, genomic, and biochemical evidence, we elucidate the complete α-agarolytic pathway in C. echini A3T. The addition of α-agarases to the agarolytic enzyme repertoire might allow marine agarolytic bacteria to increase competitive abilities through metabolic versatility.
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Ágar/metabolismo , Alteromonadaceae/metabolismo , Proteínas de Bactérias/metabolismo , Glicosídeo Hidrolases/metabolismo , Alteromonadaceae/genética , Proteínas de Bactérias/genética , Perfilação da Expressão Gênica , Genoma Bacteriano , Genômica , Glicosídeo Hidrolases/genética , Hidrólise , Família Multigênica , FilogeniaRESUMO
Polymersomes made of amphiphilic diblock copolymers are generally regarded as having higher physical and chemical stability than liposomes composed of phospholipids. This enhanced stability arises from the higher molecular weight of polymer constituents. Despite their increased stability, polymer bilayers are solubilized by detergents in a similar manner to lipid bilayers. In this work, we evaluated the stability of poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-PCL)-based polymersomes exposed to three different detergents: N-octyl-ß-d-glucopyranoside (OG), lauryldimethylamine N-oxide (LDAO), and Triton X-100 (TX-100). Changes in morphology, particle size distribution, and concentrations of the polymersomes were evaluated during the titration of the detergents into the polymersome solutions. Furthermore, we discussed the effect of detergent features on the solubilization of the polymeric bilayer and compared it to the results reported in the literature for liposomes and polymersomes. This information can be used for tuning the properties of PEG-PCL polymersomes for use in applications such as drug delivery or protein reconstitution studies.
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Pseudomonas fluorescens In5 synthesizes the antifungal cyclic lipopeptides (CLPs) nunamycin and nunapeptin, which are similar in structure and genetic organization to the pseudomonas-derived phytotoxins syringomycin and syringopeptin. Regulation of syringomycin and syringopeptin is dependent on the two-component global regulatory system GacS-GacA and the SalA, SyrF, and SyrG transcription factors, which activate syringomycin synthesis in response to plant signal molecules. Previously, we demonstrated that a specific transcription factor, NunF, positively regulates the synthesis of nunamycin and nunapeptin in P. fluorescens In5 and that the nunF gene is upregulated by fungal-associated molecules. This study focused on further unravelling the complex regulation governing CLP synthesis in P. fluorescens In5. Promoter fusions were used to show that the specific activator NunF is dependent on the global regulator of secondary metabolism GacA and is regulated by fungal-associated molecules and low temperatures. In contrast, GacA is stimulated by plant signal molecules leading to the hypothesis that P. fluorescens is a hyphosphere-associated bacterium carrying transcription factor genes that respond to signals indicating the presence of fungi and oomycetes. Based on these findings, we present a model for how synthesis of nunamycin and nunapeptin is regulated by fungal- and oomycete-associated molecules.IMPORTANCE Cyclic lipopeptide (CLP) synthesis gene clusters in pseudomonads display a high degree of synteny, and the structures of the peptides synthesized are very similar. Accordingly, the genomic island encoding the synthesis of syringomycin and syringopeptin in P. syringae pv. syringae closely resembles that of P. fluorescens In5, which contains genes coding for synthesis of the antifungal and anti-oomycete peptides nunamycin and nunapeptin, respectively. However, the regulation of syringomycin and syringopeptin synthesis is different from that of nunamycin and nunapeptin synthesis. While CLP synthesis in the plant pathogen P. syringae pv. syringae is induced by plant signal molecules, such compounds do not significantly influence synthesis of nunamycin and nunapeptin in P. fluorescens In5. Instead, fungal-associated molecules positively regulate antifungal peptide synthesis in P. fluorescens In5, while the synthesis of the global regulator GacA in P. fluorescens In5 is positively regulated by plant signal molecules but not fungal-associated molecules.
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Peptídeos Catiônicos Antimicrobianos/biossíntese , Proteínas de Bactérias/biossíntese , Agentes de Controle Biológico/metabolismo , Lipopeptídeos/biossíntese , Pseudomonas fluorescens/metabolismo , Regiões Promotoras Genéticas , Metabolismo SecundárioRESUMO
BACKGROUND: Necrotizing enterocolitis (NEC) is an acute gut inflammatory disorder that occurs in preterm infants in the first weeks after birth. Infants surviving NEC often show impaired neurodevelopment. The mechanisms linking NEC lesions with later neurodevelopment are poorly understood but may include proinflammatory signaling in the immature brain. Using preterm pigs as a model for preterm infants, we hypothesized that severe intestinal NEC lesions are associated with acute effects on the developing hippocampus. METHODS: Cesarean-delivered preterm pigs (n = 117) were reared for 8 days and spontaneously developed variable severity of NEC lesions. Neonatal arousal, physical activity, and in vitro neuritogenic effects of cerebrospinal fluid (CSF) were investigated in pigs showing NEC lesions in the colon (Co-NEC) or in the small intestine (Si-NEC). Hippocampal transcriptome analysis and qPCR were used to assess gene expressions and their relation to biological processes, including neuroinflammation, and neural plasticity. Microglia activation was quantified by stereology. The neuritogenic response to selected proteins was investigated in primary cultures of hippocampal neurons. RESULTS: NEC development rapidly reduced the physical activity of pigs, especially when lesions occurred in the small intestine. Si-NEC and Co-NEC were associated with 27 and 12 hippocampal differentially expressed genes (DEGs), respectively. These included genes related to neuroinflammation (i.e., S100A8, S100A9, IL8, IL6, MMP8, SAA, TAGLN2) and hypoxia (i.e., PDK4, IER3, TXNIP, AGER), and they were all upregulated in Si-NEC pigs. Genes related to protection against oxidative stress (HBB, ALAS2) and oligodendrocytes (OPALIN) were downregulated in Si-NEC pigs. CSF collected from NEC pigs promoted neurite outgrowth in vitro, and the S100A9 and S100A8/S100A9 proteins may mediate the neuritogenic effects of NEC-related CSF on hippocampal neurons. NEC lesions did not affect total microglial cell number but markedly increased the proportion of Iba1-positive amoeboid microglial cells. CONCLUSIONS: NEC lesions, especially when present in the small intestine, are associated with changes to hippocampal gene expression that potentially mediate neuroinflammation and disturbed neural circuit formation via enhanced neuronal differentiation. Early brain-protective interventions may be critical for preterm infants affected by intestinal NEC lesions to reduce their later neurological dysfunctions.
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Encéfalo/fisiopatologia , Citocinas/metabolismo , Enterocolite Necrosante/etiologia , Nascimento Prematuro/patologia , Nascimento Prematuro/fisiopatologia , Animais , Encéfalo/patologia , Líquido Cefalorraquidiano/metabolismo , Proteínas de Ligação a DNA/metabolismo , Trato Gastrointestinal/metabolismo , Hipóxia/metabolismo , Inflamação/etiologia , Microglia/metabolismo , Microglia/patologia , Proteínas do Tecido Nervoso/metabolismo , Crescimento Neuronal , Condicionamento Físico Animal , Proteínas S100/metabolismo , Suínos , Fatores de Tempo , Transcriptoma/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
A novel bacterial strain, A3T, was isolated from the intestines of the sea urchin Strongylocentrotus droebachiensis collected in Øresund, Denmark. The strain was Gram-reaction-negative, rod-shaped and facultatively anaerobic, and displayed growth at 5-25 °C (optimum 20 °C), pH 7-9 (optimum at pH 7) and 1-6â% (w/v) NaCl (optimum 3â%). Furthermore, strain A3T grew on agar, agarose, κ-carrageenan, alginate and laminarin as sole carbon source. Complete liquefaction of agar and κ-carrageenan was observed on solid plate media as a result of enzymatic activities. Major fatty acids were summed feature 3 (C16â:â1ω7c and/or C16â:â1ω6c) and C16â:â0. The respiratory quinones were determined to be ubiquinones Q-8 (92â%) and Q-7 (8â%), and polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 36.9 mol%. Phylogenetical analyses based on the 16S rRNA gene showed that the bacterium was affiliated with the genus Colwellia within the Alteromonadaceae of the Gammaproteobacteria. The level of 16S rRNA gene sequence similarity between strain A3T and its closest relatives in the genus Colwellia (C. psychrerythraea ATCC 27364T and C. asteriadis KMD 002T) was 97.5â%. The average nucleotide identity between strain A3T and other members of Colwellia was 78.6-80.5â%, and DNA-DNA hybridization prediction revealed values of less than 23â% relatedness between strain A3T and other Colwellia species. The phenotypic, phylogenetic and genomic analyses support the hypothesis that strain A3T represents a novel species of the genus Colwellia, for which the name Colwellia echini sp. nov. is proposed. The type strain is A3T (=LMG 30125T=NCIMB 15095T).
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Alteromonadaceae/classificação , Filogenia , Strongylocentrotus/microbiologia , Ágar , Alginatos , Alteromonadaceae/genética , Alteromonadaceae/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Carragenina , DNA Bacteriano/genética , Dinamarca , Ácidos Graxos/química , Gammaproteobacteria , Glucanos , Ácido Glucurônico , Ácidos Hexurônicos , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química , RNA Ribossômico 16S/genética , Sefarose , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
To facilitate communications between care levels and improve coordination during hospital discharges, there is great potential in using information and communication technology systems, because they can significantly help to deter unnecessary readmissions. However, there is still a lack of knowledge about how often nurses use information and communication technology and the indicators related to its use. The aims of this study were to describe the indicators related to nurses' use of an information and communication technology system for collaboration between care levels and to estimate whether the level of use can be related to nurses' perceptions of the information and communication technology system's contribution to improve coordination during hospital discharges. A quantitative survey of 37 nurses from 11 primary healthcare centers was performed in a county in southern Sweden. The data were analyzed using descriptive and comparative analyses. The results showed that perceptions concerning the information and communication technology system's usability and time consumption differed between nurses who used the system and those who did not. Simultaneously, the nurses were rather unaware of the ability of the information and communication technology system to improve coordination during patient discharges.
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Comportamento Cooperativo , Troca de Informação em Saúde/estatística & dados numéricos , Papel do Profissional de Enfermagem/psicologia , Alta do Paciente , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Atenção Primária à Saúde , Inquéritos e Questionários , SuéciaAssuntos
Clínicos Gerais , Neoplasias/terapia , Papel do Médico , Assistência ao Convalescente , Detecção Precoce de Câncer , Medicina Geral , Humanos , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Neoplasias/reabilitação , Cuidados Paliativos , Pacotes de Assistência ao Paciente , Qualidade da Assistência à SaúdeRESUMO
Introduction: A life story (LS) is a tool healthcare professionals (HCPs) use to help older adults with dementia preserve their identities by sharing their stories. Applied health technology can be considered a niche within welfare technology. Combining technology and nursing, such as using life stories in digital form, may support person-centred care and allow HCPs to see the person behind the disease. Objective: The study's objective was to summarise and describe the use of life stories in digital form in the daily care of older adults with dementia. Methods: A scoping review was conducted in five stages. Database searches were conducted in Cinahl, PubMed, Scopus, Web of Science, and Google Scholar; 31 articles were included. A conventional qualitative content analysis of the collected data was conducted. Results: The qualitative analysis resulted in three categories: (1) benefits for older adults, (2) influence on HCPs' work, and (3) obstacles to implementing a digital LS in daily care. Conclusion: Older adults with dementia can receive person-centred care through a digital LS based on their wishes. A digital LS can enable symmetric communication and serve as an intergenerational communication tool. It can be used to handle behavioural symptoms. Using a digital LS in the later stages of dementia may differ from using it earlier in dementia. However, it may compensate for weakening abilities in older adults by enhancing social interaction.
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SCOPE: Processing of whey protein concentrate (WPC) for infant formulas may induce protein modifications with severe consequences for preterm newborn development. The study investigates how conventional WPC and a gently processed skim milk-derived WPC (SPC) affect gut and immune development after birth. METHODS AND RESULTS: Newborn, preterm pigs used as a model of preterm infants were fed formula containing WPC, SPC, extra heat-treated SPC (HT-SPC), or stored HT-SPC (HTS-SPC) for 5 days. SPC contained no protein aggregates and more native lactoferrin, and despite higher Maillard reaction product (MRP) formation, the clinical response and most gut and immune parameters are similar to WPC pigs. SPC feeding negatively impacts intestinal MRP accumulation, mucosa, and bacterial diversity. In contrast, circulating T-cells are decreased and oxidative stress- and inflammation-related genes are upregulated in WPC pigs. Protein aggregation and MRP formation increase in HTS-SPC, leading to reduced antibacterial activity, lactase/maltase ratio, circulating neutrophils, and cytotoxic T-cells besides increased gut MRP accumulation and expression of TNFAIP3. CONCLUSION: The gently processed SPC has more native protein, but higher MRP levels than WPC, resulting in similar tolerability but subclinical adverse gut effects in preterm pigs. Additional heat treatment and storage further induce MRP formation, gut inflammation, and intestinal mucosal damage.
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Fórmulas Infantis , Leite , Humanos , Recém-Nascido , Lactente , Animais , Suínos , Proteínas do Soro do Leite , Intestinos/fisiologia , Recém-Nascido Prematuro , InflamaçãoRESUMO
Very preterm infants show low levels of insulin-like growth factor-1 (IGF-1), which is associated with postnatal growth restriction and poor neurologic outcomes. It remains unknown whether supplemental IGF-1 may stimulate neurodevelopment in preterm neonates. Using cesarean-delivered preterm pigs as a model of preterm infants, we investigated the effects of supplemental IGF-1 on motor function and on regional and cellular brain development. Pigs were treated with 2.25 mg/kg/d recombinant human IGF-1/IGF binding protein-3 complex from birth until day 5 or 9 before the collection of brain samples for quantitative immunohistochemistry (IHC), RNA sequencing, and quantitative PCR analyses. Brain protein synthesis was measured using in vivo labeling with [2H5] phenylalanine. We showed that the IGF-1 receptor was widely distributed in the brain and largely coexisted with immature neurons. Region-specific quantification of IHC labeling showed that IGF-1 treatment promoted neuronal differentiation, increased subcortical myelination, and attenuated synaptogenesis in a region-dependent and time-dependent manner. The expression levels of genes involved in neuronal and oligodendrocyte maturation, and angiogenic and transport functions were altered, reflecting enhanced brain maturation in response to IGF-1 treatment. Cerebellar protein synthesis was increased by 19% at day 5 and 14% at day 9 after IGF-1 treatment. Treatment had no effect on Iba1+ microglia or regional brain weights and did not affect motor development or the expression of genes related to IGF-1 signaling. In conclusion, the data show that supplemental IGF-1 promotes brain maturation in newborn preterm pigs. The results provide further support for IGF-1 supplementation therapy in the early postnatal period in preterm infants.
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Recém-Nascido Prematuro , Fator de Crescimento Insulin-Like I , Gravidez , Feminino , Animais , Suínos , Recém-Nascido , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Encéfalo/metabolismo , Cerebelo/metabolismo , Suplementos NutricionaisRESUMO
Introduction: Preterm infants have increased risk of impaired neurodevelopment to which reduced systemic levels of insulin-like growth factor 1 (IGF-1) in the weeks after birth may play a role. Hence, we hypothesized that postnatal IGF-1 supplementation would improve brain development in preterm pigs, used as a model for preterm infants. Methods: Preterm pigs delivered by cesarean section received recombinant human IGF-1/IGF binding protein-3 complex (rhIGF-1/rhIGFBP-3, 2.25 mg/kg/day) or vehicle from birth to postnatal day 19. Motor function and cognition were assessed by monitoring of in-cage and open field activities, balance beam test, gait parameters, novel object recognition and operant conditioning tests. Collected brains were subject to magnetic resonance imaging (MRI), immunohistochemistry, gene expression analyses and protein synthesis measurements. Results: The IGF-1 treatment increased cerebellar protein synthesis rates (both in vivo and ex vivo). Performance in the balance beam test was improved by IGF-1 but not in other neurofunctional tests. The treatment decreased total and relative caudate nucleus weights, without any effects to total brain weight or grey/white matter volumes. Supplementation with IGF-1 reduced myelination in caudate nucleus, cerebellum, and white matter regions and decreased hilar synapse formation, without effects to oligodendrocyte maturation or neuron differentiation. Gene expression analyses indicated enhanced maturation of the GABAergic system in the caudate nucleus (decreased NKCC1:KCC2 ratio) with limited effects in cerebellum or hippocampus. Conclusion: Supplemental IGF-1 during the first three weeks after preterm birth may support motor function by enhancing GABAergic maturation in the caudate nucleus, despite reduced myelination. Supplemental IGF-1 may support postnatal brain development in preterm infants, but more studies are required to identify optimal treatment regimens for subgroups of very or extremely preterm infants.
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Breast milk has neurodevelopmental advantages compared to infant formula, especially in low-birth-weight infants, which may in part relate to the fat source. This study compared neurodevelopmental outcomes in three-day-old normal birth weight (NBW) and intrauterine growth restricted (IUGR) piglets fed a formula diet with either vegetable oil (VEG) or bovine milk fat sources (MILK) for three weeks in a 2 × 2 factorial design. Behavioural tests, lipidomics, MRI and RNA sequencing analyses of plasma and brain tissue were conducted. The absolute levels of 82% and 11% of lipid molecules were different between dietary groups in plasma and hippocampus, respectively. Of the lipid molecules with differential abundance in the hippocampus, the majority were upregulated in MILK versus VEG, and they mainly belonged to the group of glycerophospholipids. Lower absolute brain weights, absolute grey and white matter volumes and behaviour and motor function scores, and higher relative total brain weights were present in IUGR compared to NBW with minor influence of diet. Cognitive function and cerebellar gene expression profiles were similar for dietary and weight groups, and overall only minor interactive effects between diet and birth weight were observed. Overall, we show that the dietary fat source influences the plasma and to a lesser degree the hippocampal lipidome and is unable to improve on IUGR-induced brain structural and functional impairments.
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Lipidômica , Verduras , Animais , Peso ao Nascer , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Dieta , Gorduras na Dieta , Retardo do Crescimento Fetal/metabolismo , Humanos , SuínosRESUMO
Background: Quality of life (QoL) is affected even at early stages in older adults with cognitive impairment. The use of mobile health (mHealth) technology can offer support in daily life and improve the physical and mental health of older adults. However, a clarification of how mHealth technology can be used to support the QoL of older adults with cognitive impairment is needed. Objective: To investigate factors affecting mHealth technology use in relation to self-rated QoL among older adults with cognitive impairment. Methods: A cross-sectional research design was used to analyse mHealth technology use and QoL in 1,082 older participants. Baseline data were used from a multi-centered randomized controlled trial including QoL, measured by the Quality of Life in Alzheimer's Disease (QoL-AD) Scale, as the outcome variable. Data were analyzed using logistic regression models. Results: Having moderately or high technical skills in using mHealth technology and using the internet via mHealth technology on a daily or weekly basis was associated with good to excellent QoL in older adults with cognitive impairment. Conclusions: The variation in technical skills and internet use among the participants can be interpreted as an obstacle for mHealth technology to support QoL.
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Digital health technologies such as mobile health (mHealth) are considered to have the potential to support the needs of older adults with cognitive impairment. However, the evidence for improving health with the use of mHealth applications is of limited quality. Few studies have reported on the consequences of technology use concerning the older adults' quality of life. The purpose of this study was to describe perceptions of mHealth and its impact on health-related quality of life (HRQoL) among older adults with cognitive impairment. The study was conducted using a qualitative design with a phenomenographic approach. A total of 18 older participants with cognitive impairment were interviewed. The interviews were analyzed in order to apply phenomenography in a home-care context. The results showed variations in the older adults' perceptions that were comprised within three categories of description; Require technology literacy, Maintain social interaction, and Facilitate independent living. In conclusion, the development and design of mHealth technologies need to be tailored based on older adults´ needs in order to be understood and perceived as useful in a home-care context. For mHealth to support HRQoL, healthcare should be provided in a way that encourages various forms of communication and interaction.
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Disfunção Cognitiva , Serviços de Assistência Domiciliar , Aplicativos Móveis , Telemedicina , Idoso , Disfunção Cognitiva/terapia , Feminino , Humanos , Masculino , Qualidade de VidaRESUMO
Algal cell wall polysaccharides constitute a large fraction in the biomass of marine primary producers and are thus important in nutrient transfer between trophic levels in the marine ecosystem. In order for this transfer to take place, polysaccharides must be degraded into smaller mono- and disaccharide units, which are subsequently metabolized, and key components in this degradation are bacterial enzymes. The marine bacterium Colwellia echini A3T is a potent enzyme producer since it completely hydrolyzes agar and κ-carrageenan. Here, we report that the genome of C. echini A3T harbors two large gene clusters for the degradation of carrageenan and agar, respectively. Phylogenetical and functional studies combined with transcriptomics and in silico structural modeling revealed that the carrageenolytic cluster encodes furcellaranases, a new class of glycoside hydrolase family 16 (GH16) enzymes that are key enzymes for hydrolysis of furcellaran, a hybrid carrageenan containing both ß- and κ-carrageenan motifs. We show that furcellaranases degrade furcellaran into neocarratetraose-43-O-monosulfate [DA-(α1,3)-G4S-(ß1,4)-DA-(α1,3)-G], and we propose a molecular model of furcellaranases and compare the active site architectures of furcellaranases, κ-carrageenases, ß-agarases, and ß-porphyranases. Furthermore, C. echini A3T was shown to encode κ-carrageenases, ι-carrageenases, and members of a new class of enzymes, active only on hybrid ß/κ-carrageenan tetrasaccharides. On the basis of our genomic, transcriptomic, and functional analyses of the carrageenolytic enzyme repertoire, we propose a new model for how C. echini A3T degrades complex sulfated marine polysaccharides such as furcellaran, κ-carrageenan, and ι-carrageenan.IMPORTANCE Here, we report that a recently described bacterium, Colwellia echini, harbors a large number of enzymes enabling the bacterium to grow on κ-carrageenan and agar. The genes are organized in two clusters that encode enzymes for the total degradation of κ-carrageenan and agar, respectively. As the first, we report on the structure/function relationship of a new class of enzymes that hydrolyze furcellaran, a partially sulfated ß/κ-carrageenan. Using an in silico model, we hypothesize a molecular structure of furcellaranases and compare structural features and active site architectures of furcellaranases with those of other GH16 polysaccharide hydrolases, such as κ-carrageenases, ß-agarases, and ß-porphyranases. Furthermore, we describe a new class of enzymes distantly related to GH42 and GH160 ß-galactosidases and show that this new class of enzymes is active only on hybrid ß/κ-carrageenan oligosaccharides. Finally, we propose a new model for how the carrageenolytic enzyme repertoire enables C. echini to metabolize ß/κ-, κ-, and ι-carrageenan.
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Alteromonadaceae/enzimologia , Alteromonadaceae/genética , Proteínas de Bactérias/genética , Carragenina/metabolismo , Família Multigênica , Polissacarídeos/metabolismo , Ágar/metabolismo , Alginatos/metabolismo , Proteínas de Bactérias/metabolismo , Simulação por Computador , Perfilação da Expressão Gênica , Modelos Moleculares , Filogenia , Gomas Vegetais/metabolismo , Polissacarídeos/genéticaRESUMO
AIM: This study aimed to identify factors affecting health-related quality of life (HRQoL) of older adults with cognitive impairment and to describe the association of these factors with different components of HRQoL. DESIGN: A cross-sectional, descriptive research design was used. METHODS: Data were collected from 247 individuals aged 60 years and older from a Swedish longitudinal cohort study. The Short-Form Health Survey-12 (SF-12) and EuroQol (EQ-5D) were used to assess HRQoL. The data were analysed using descriptive and comparative statistics. RESULTS: The present study identified several factors that influenced HRQoL of older adults with cognitive impairment. The results of a multiple logistic regression analysis revealed that the following factors were associated with physical and mental HRQoL: dependency in activities of daily living (ADL), receiving informal care and feelings of loneliness and pain.
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Fluorescence-based reporter systems are valuable tools for studying gene expression dynamics in living cells. Here we describe a dual-fluorescence reporter system carrying the red fluorescent marker mCherry and the blue fluorescent protein EBFP2 enabling the simultaneous analysis of two promoters in broad-host range autofluorescent Gram-negative bacteria.