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1.
Nature ; 611(7937): 827-834, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36418452

RESUMO

Vacuolar-type adenosine triphosphatases (V-ATPases)1-3 are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases4,5. They hydrolyse ATP to establish electrochemical proton gradients for a plethora of cellular processes1,3. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by about one V-ATPase molecule per synaptic vesicle6,7. To shed light on this bona fide single-molecule biological process, we investigated electrogenic proton-pumping by single mammalian-brain V-ATPases in single synaptic vesicles. Here we show that V-ATPases do not pump continuously in time, as suggested by observing the rotation of bacterial homologues8 and assuming strict ATP-proton coupling. Instead, they stochastically switch between three ultralong-lived modes: proton-pumping, inactive and proton-leaky. Notably, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. ATP regulates V-ATPase activity through the switching probability of the proton-pumping mode. By contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. A direct consequence of mode-switching is all-or-none stochastic fluctuations in the electrochemical gradient of synaptic vesicles that would be expected to introduce stochasticity in proton-driven secondary active loading of neurotransmitters and may thus have important implications for neurotransmission. This work reveals and emphasizes the mechanistic and biological importance of ultraslow mode-switching.


Assuntos
Encéfalo , Mamíferos , ATPases Vacuolares Próton-Translocadoras , Animais , Trifosfato de Adenosina/metabolismo , Encéfalo/enzimologia , Encéfalo/metabolismo , Mamíferos/metabolismo , Prótons , Vesículas Sinápticas/enzimologia , Vesículas Sinápticas/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Neurotransmissores/metabolismo , Transmissão Sináptica , Fatores de Tempo , Cinética
2.
EMBO J ; 41(10): e109622, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35178710

RESUMO

Understanding the molecular pathways driving the acute antiviral and inflammatory response to SARS-CoV-2 infection is critical for developing treatments for severe COVID-19. Here, we find decreasing number of circulating plasmacytoid dendritic cells (pDCs) in COVID-19 patients early after symptom onset, correlating with disease severity. pDC depletion is transient and coincides with decreased expression of antiviral type I IFNα and of systemic inflammatory cytokines CXCL10 and IL-6. Using an in vitro stem cell-based human pDC model, we further demonstrate that pDCs, while not supporting SARS-CoV-2 replication, directly sense the virus and in response produce multiple antiviral (interferons: IFNα and IFNλ1) and inflammatory (IL-6, IL-8, CXCL10) cytokines that protect epithelial cells from de novo SARS-CoV-2 infection. Via targeted deletion of virus-recognition innate immune pathways, we identify TLR7-MyD88 signaling as crucial for production of antiviral interferons (IFNs), whereas Toll-like receptor (TLR)2 is responsible for the inflammatory IL-6 response. We further show that SARS-CoV-2 engages the receptor neuropilin-1 on pDCs to selectively mitigate the antiviral interferon response, but not the IL-6 response, suggesting neuropilin-1 as potential therapeutic target for stimulation of TLR7-mediated antiviral protection.


Assuntos
COVID-19 , Células Dendríticas , Receptor 2 Toll-Like , Receptor 7 Toll-Like , COVID-19/imunologia , COVID-19/patologia , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/patologia , Humanos , Interferon Tipo I/imunologia , Interferon-alfa/imunologia , Interleucina-6/imunologia , Neuropilina-1/imunologia , SARS-CoV-2 , Receptor 2 Toll-Like/imunologia , Receptor 7 Toll-Like/imunologia
3.
Physiol Plant ; 176(3): e14376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38837784

RESUMO

Variations in light intensity induce cytosol pH changes in photosynthetic tissues, providing a possible signal to adjust a variety of biochemical, physiological and developmental processes to the energy status of the cells. It was shown that these pH changes are partially due to the transport of protons in or out of the thylakoid lumen. However, the ion transporters in the chloroplast that transmit these pH changes to the cytosol are not known. KEA1 and KEA2 are K+/H+ antiporters in the chloroplast inner envelope that adjust stromal pH in light-to-dark transitions. We previously determined that stromal pH is higher in kea1kea2 mutant cells. In this study, we now show that KEA1 and KEA2 are required to attenuate cytosol pH variations upon sudden light intensity changes in leaf mesophyll cells, showing they are important components of the light-modulated pH signalling module. The kea1kea2 mutant mesophyll cells also have a considerably less negative membrane potential. Membrane potential is dependent on the activity of the plasma membrane proton ATPase and is regulated by secondary ion transporters, mainly potassium channels in the plasma membrane. We did not find significant differences in the activity of the plasma membrane proton pump but found a strongly increased membrane permeability to protons, especially potassium, of the double mutant plasma membranes. Our results indicate that chloroplast envelope K+/H+ antiporters not only affect chloroplast pH but also have a strong impact on cellular ion homeostasis and energization of the plasma membrane.


Assuntos
Arabidopsis , Cloroplastos , Citosol , Antiportadores de Potássio-Hidrogênio , Concentração de Íons de Hidrogênio , Citosol/metabolismo , Cloroplastos/metabolismo , Antiportadores de Potássio-Hidrogênio/metabolismo , Antiportadores de Potássio-Hidrogênio/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Luz , Potenciais da Membrana , Potássio/metabolismo , Células do Mesofilo/metabolismo , Mutação/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/efeitos da radiação
4.
Scand J Public Health ; 51(8): 1173-1181, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35708326

RESUMO

AIMS: Little is known about the influence of parents' screen media habits and attitudes towards screen media on children's screen use. We investigated associations of parental screen use, their smartphone addiction and screen media attitudes, with children's recreational screen use. METHODS: This study was based on a population-based cross-sectional survey sent between May 2019 and November 2020 to a random sample of 6820 Danish parent-child dyads who answered questions regarding their screen media habits. Children were 6-11 years of age and had to reside with the parent. Multivariable adjusted regression analyses were conducted (in October 2021) separately for screen media use on weekdays and weekend days. RESULTS: The analyses included 5437 parents (41.0 years, 67.6% girls) and 5437 children (8.9 years, 48.2% girls). The adjusted relative odds of excessive amounts of screen use of children (>3 hours/weekday and >4 hours/weekend day) was 5.8 (95% confidence interval (CI) 4.6; 7.3) on weekdays and 7.2 (95% CI 5.9; 8.8) on weekend days comparing the fourth and first quartile of parental screen use. Children of parents in the fourth quartile of parental screen use had 2.1 (95% CI 1.7; 2.5) and 2.5 (95% CI 2.2; 3.0) greater odds of screen use before bedtime on all week and weekend days, respectively. Children of parents who had a positive attitude towards their child's screen use or were at high risk of smartphone addiction had significantly higher screen use and more frequent problematic screen use. CONCLUSIONS: Parent's screen media habits and attitudes were strongly associated with their children's recreational screen use.


Assuntos
Atitude , Pais , Feminino , Humanos , Criança , Masculino , Estudos Transversais , Hábitos , Dinamarca , Relações Pais-Filho , Inquéritos e Questionários
5.
Proc Natl Acad Sci U S A ; 117(34): 20920-20925, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32788371

RESUMO

In plants, environmental stressors trigger plasma membrane depolarizations. Being electrically interconnected via plasmodesmata, proper functional dissection of electrical signaling by electrophysiology is basically impossible. The green alga Chlamydomonas reinhardtii evolved blue light-excited channelrhodopsins (ChR1, 2) to navigate. When expressed in excitable nerve and muscle cells, ChRs can be used to control the membrane potential via illumination. In Arabidopsis plants, we used the algal ChR2-light switches as tools to stimulate plasmodesmata-interconnected photosynthetic cell networks by blue light and monitor the subsequent plasma membrane electrical responses. Blue-dependent stimulations of ChR2 expressing mesophyll cells, resting around -160 to -180 mV, reproducibly depolarized the membrane potential by 95 mV on average. Following excitation, mesophyll cells recovered their prestimulus potential not without transiently passing a hyperpolarization state. By combining optogenetics with voltage-sensing microelectrodes, we demonstrate that plant plasma membrane AHA-type H+-ATPase governs the gross repolarization process. AHA2 protein biochemistry and functional expression analysis in Xenopus oocytes indicates that the capacity of this H+ pump to recharge the membrane potential is rooted in its voltage- and pH-dependent functional anatomy. Thus, ChR2 optogenetics appears well suited to noninvasively expose plant cells to signal specific depolarization signatures. From the responses we learn about the molecular processes, plants employ to channel stress-associated membrane excitations into physiological responses.


Assuntos
Membrana Celular/metabolismo , Channelrhodopsins/metabolismo , Bombas de Próton/metabolismo , Adenosina Trifosfatases/metabolismo , Proteínas de Algas/metabolismo , Channelrhodopsins/fisiologia , Chlamydomonas reinhardtii/metabolismo , Cor , Concentração de Íons de Hidrogênio , Luz , Potenciais da Membrana/fisiologia , Optogenética/métodos , Bombas de Próton/fisiologia , Rodopsina/metabolismo , Transdução de Sinais
6.
Prev Med ; 155: 106908, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34915040

RESUMO

Screen media use is part of most children's everyday lives, but organisations have advised that use should be limited. The aims of this study were to describe 6-11-year-old Danish children's screen device ownership and screen media use (weekdays and weekends), including the role of parental education, family structure and household screen media rules. We conducted a cross-sectional study including 5274 Danish children aged 6-11-years sampled from ten Danish municipalities from May 2019 to November 2020. Characteristics of the sample and source population were obtained from the Danish Health Data Authority. Parent's completed the SCREENS questionnaire, which was developed to assess children's screen media habits. We used inverse probability weighted logistic and linear regression models. Smartphone and laptop ownership was higher with increasing age, and use of screen media varied across day type, age and gender. The proportion of children using screen media more than 4 h/day was 13% (95% CI 12%;14%) for weekdays and 28% (95% CI 27%;29%) for weekend days. Children of parents with medium-length or long educations had statistically significant lower odds of using screen media more than 4 h/day. We found a statistically significant graded relationship between household screen media rules and children's screen media use; the less parents reported presence of rules, the more time their children spent on screen media engagements. Our results suggest that parental educational level and family structure are related to unfavourable screen media habits, and household screen media rules may play an important role for parents to limit children's screen use.


Assuntos
Comportamento Infantil , Televisão , Criança , Estudos Transversais , Dinamarca , Humanos , Pais , Inquéritos e Questionários
7.
Biochem J ; 478(3): 619-632, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33427868

RESUMO

Sulfur-containing amino acid residues function in antioxidative responses, which can be induced by the reactive oxygen species generated by excessive copper and hydrogen peroxide. In all Na+/K+, Ca2+, and H+ pumping P-type ATPases, a cysteine residue is present two residues upstream of the essential aspartate residue, which is obligatorily phosphorylated in each catalytic cycle. Despite its conservation, the function of this cysteine residue was hitherto unknown. In this study, we analyzed the function of the corresponding cysteine residue (Cys-327) in the autoinhibited plasma membrane H+-ATPase isoform 2 (AHA2) from Arabidopsis thaliana by mutagenesis and heterologous expression in a yeast host. Enzyme kinetics of alanine, serine, and leucine substitutions were identical with those of the wild-type pump but the sensitivity of the mutant pumps was increased towards copper and hydrogen peroxide. Peptide identification and sequencing by mass spectrometry demonstrated that Cys-327 was prone to oxidation. These data suggest that Cys-327 functions as a protective residue in the plasma membrane H+-ATPase, and possibly in other P-type ATPases as well.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/enzimologia , Cisteína/química , ATPases Translocadoras de Prótons/química , Alquilação , Sequência de Aminoácidos , Substituição de Aminoácidos , Proteínas de Arabidopsis/antagonistas & inibidores , Sequência Conservada , Cobre/metabolismo , Peróxido de Hidrogênio/metabolismo , Iodoacetamida/farmacologia , Cinética , Microssomos/metabolismo , Modelos Moleculares , Mutagênese Sítio-Dirigida , Oxirredução , Conformação Proteica , Domínios Proteicos , ATPases Translocadoras de Prótons/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
8.
Scand J Public Health ; 49(5): 495-502, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32267814

RESUMO

Aims: To examine prospective and cross-sectional associations between screen time and blood pressure (BP) in preschool children. Methods: The Odense Child Cohort study started in January 2010. Children who were born in the municipality of Odense underwent a clinical examination at 3 and 5 years of age and their parents were asked to complete a questionnaire. A total of 628 children were included in the prospective analysis and 964 children were included in two cross-sectional analyses at 5 years of age. Multivariable adjusted linear and logistic regression models were computed to examine prospective and cross-sectional associations between screen time and BP with adjustment for putative confounding factors. Results: No significant prospective association was found between a 2-year change in screen time and systolic BP (0.55 BP percentile change per 1 h increase in screen time, 95% confidence interval (CI) -1.51 to 2.60) and diastolic BP (0.74 BP percentile change per 1 h increase in screen time, 95% CI -1.09 to 2.57). No significant cross-sectional association was observed between screen time (⩽1 h/day, >1-2 h/day, >2 h/day) and the prevalence of high BP at 5 years of age. Exposure to screen time before bedtime 2-5 days/week and ⩾6 days/week was significantly associated with a greater prevalence of high BP compared with screen time before bedtime 0-1 day/week (odds ratios 1.57 (95% CI 1.02-2.42) and 1.82 (95% CI 1.18-2.89), respectively. Conclusions: No prospective association was found between screen time and BP. However, a significant cross-sectional association was found between screen time before bedtime and high BP in preschool children.


Assuntos
Hipertensão/epidemiologia , Meios de Comunicação de Massa/estatística & dados numéricos , Tempo de Tela , Pré-Escolar , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo
9.
Eur Child Adolesc Psychiatry ; 30(5): 699-710, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32388627

RESUMO

Mentalization-based treatment in groups (MBT-G) has never been tested in adolescents with Borderline Personality Disorder (BPD) in a randomized controlled trial. The current study aimed to test the long-term effectiveness of MBT-G in an adolescent sample with BPD or BPD features (≥ 4 DSM-5 BPD criteria). Hundred and eleven patients with BPD (n = 106) or BPD features (n = 5) were randomized to either (1) a 1-year modified MBT-G program comprising three MBT introductory sessions, five individual case formulation sessions, 37 weekly MBT group sessions, and six MBT-Parent sessions, or (2) treatment as usual (TAU), defined as at least 12 individual monthly treatment sessions with follow-up assessments at 3 and 12 months post treatment. The primary outcome was the score on the Borderline Personality Features Scale for Children (BPFS-C), and secondary outcomes included clinician-rated BPD symptoms and global level of functioning as well as self-reported self-harm, depression, externalizing and internalizing symptoms, and caregiver reports. There were no statistically significant differences between MBT-G and TAU on the primary outcome measure or any of the secondary outcomes. Both groups showed improvement on the majority of clinical and social outcomes at both follow-up points, although remission rates were modest with just 35% in MBT-G and 39% in TAU 2 years after inclusion into the study. MBT-G was not superior to TAU in improving borderline features in adolescents. Although improvement was observed equally in both interventions over time, the patients continued to exhibit prominent BPD features, general psychopathology and decreased functioning in the follow-up period, which points to a need for more research and better understanding of effective components in early intervention programs. The ClinicalTrials.gov identifier is NCT02068326.


Assuntos
Transtorno da Personalidade Borderline/terapia , Mentalização/fisiologia , Comportamento Autodestrutivo/psicologia , Adolescente , Feminino , Seguimentos , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
10.
Sensors (Basel) ; 21(24)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34960533

RESUMO

With the emergence of machine learning for the classification of sleep and other human behaviors from accelerometer data, the need for correctly annotated data is higher than ever. We present and evaluate a novel method for the manual annotation of in-bed periods in accelerometer data using the open-source software Audacity®, and we compare the method to the EEG-based sleep monitoring device Zmachine® Insight+ and self-reported sleep diaries. For evaluating the manual annotation method, we calculated the inter- and intra-rater agreement and agreement with Zmachine and sleep diaries using interclass correlation coefficients and Bland-Altman analysis. Our results showed excellent inter- and intra-rater agreement and excellent agreement with Zmachine and sleep diaries. The Bland-Altman limits of agreement were generally around ±30 min for the comparison between the manual annotation and the Zmachine timestamps for the in-bed period. Moreover, the mean bias was minuscule. We conclude that the manual annotation method presented is a viable option for annotating in-bed periods in accelerometer data, which will further qualify datasets without labeling or sleep records.


Assuntos
Acelerometria , Sono , Eletroencefalografia , Humanos , Aprendizado de Máquina , Reprodutibilidade dos Testes
11.
Chem Res Toxicol ; 33(12): 3041-3047, 2020 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-33156617

RESUMO

Inorganic arsenic is one of the most toxic and carcinogenic substances in the environment, but many organisms, including humans, methylate inorganic arsenic to mono-, di-, and trimethylated arsenic metabolites, which the organism can excrete. In humans and other eukaryotic organisms, the arsenite methyltransferase (AS3MT) protein methylates arsenite. AS3MT sequences from eukaryotic organisms group phylogenetically with predicted eubacterial AS3MT sequences, which has led to the suggestion that AS3MT was acquired from eubacteria by multiple events of horizontal gene transfer. In this study, we evaluated whether 55 (out of which 47 were predicted based on protein sequence similarity) sequences encoding putative AS3MT orthologues in 47 species from different kingdoms can indeed methylate arsenic. Fifty-three of the proteins showed arsenic methylating capacity. For example, the predicted AS3MT of the human gut bacterium Faecalibacterium prausnitzii methylated arsenic efficiently. We performed a kinetic analysis of 14 AS3MT proteins representing two phylogenetically distinct clades (Group 1 and 2) that each contain both eubacterial and eukaryotic sequences. We found that animal and bacterial AS3MTs in Group 1 rarely produce trimethylated arsenic, whereas Hydra vulgaris and the bacterium Rhodopseudomonas palustris in Group 2 produce trimethylated arsenic metabolites. These findings suggest that animals during evolution have acquired different arsenic methylating phenotypes from different bacteria. Further, it shows that humans carry two bacterial systems for arsenic methylation: one bacterium-derived AS3MT from Group 1 incorporated in the human genome and one from Group 2 in F. prausnitzii present in the gut microbiome.


Assuntos
Arsênio/metabolismo , Metiltransferases/metabolismo , Animais , Faecalibacterium prausnitzii/enzimologia , Microbioma Gastrointestinal , Humanos , Hydra/enzimologia , Metilação , Metiltransferases/genética , Filogenia , Rodopseudomonas/enzimologia
12.
J Child Psychol Psychiatry ; 61(5): 594-604, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31702058

RESUMO

BACKGROUND: Borderline personality disorder (BPD) typically onsets in adolescence and predicts later functional disability in adulthood. Highly structured evidence-based psychotherapeutic programs, including mentalization-based treatment (MBT), are first choice treatment. The efficacy of MBT for BPD has mainly been tested with adults, and no RCT has examined the effectiveness of MBT in groups (MBT-G) for adolescent BPD. METHOD: A total of 112 adolescents (111 females) with BPD (106) or BPD symptoms ≥4 DSM-5 criteria (5) referred to child and adolescent psychiatric outpatient clinics were randomized to a 1-year MBT-G, consisting of three introductory, psychoeducative sessions, 37 weekly group sessions, five individual case formulation sessions, and six group sessions for caregivers, or treatment as usual (TAU) with at least 12 monthly individual sessions. The primary outcome was the score on the borderline personality features scale for children (BPFS-C); secondary outcomes included self-harm, depression, externalizing and internalizing symptoms (all self-report), caregiver reports, social functioning, and borderline symptoms rated by blinded clinicians. Outcome assessments were made at baseline, after 10, 20, and 30 weeks, and at end of treatment (EOT). The ClinicalTrials.gov identifier is NCT02068326. RESULTS: At EOT, the primary outcome was 71.3 (SD = 15.0) in the MBT-G group and 71.3 (SD = 15.2) in the TAU group (adjusted mean difference 0.4 BPFS-C units in favor of MBT-G, 95% confidence interval -6.3 to 7.1, p = .91). No significant group differences were found in the secondary outcomes. 29% in both groups remitted. 29% of the MBT group completed less than half of the sessions compared with 7% of the control group. CONCLUSIONS: There is no indication for superiority of either therapy method. The low remission rate points to the importance of continued research into early intervention. Specifically, retention problems need to be addressed.


Assuntos
Transtorno da Personalidade Borderline/psicologia , Transtorno da Personalidade Borderline/terapia , Mentalização , Adolescente , Adulto , Depressão , Feminino , Humanos , Controle Interno-Externo , Masculino , Comportamento Autodestrutivo , Resultado do Tratamento
13.
AJR Am J Roentgenol ; 214(6): 1269-1279, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32255690

RESUMO

OBJECTIVE. The purpose of this study is to establish whether texture analysis and densitometry are complementary quantitative measures of chronic obstructive pulmonary disease (COPD) in a lung cancer screening setting. MATERIALS AND METHODS. This was a retrospective study of data collected prospectively (in 2004-2010) in the Danish Lung Cancer Screening Trial. The texture score, relative area of emphysema, and percentile density were computed for 1915 baseline low-dose lung CT scans and were evaluated, both individually and in combination, for associations with lung function (i.e., forced expiratory volume in 1 second as a percentage of predicted normal [FEV1% predicted]), diagnosis of mild to severe COPD, and prediction of a rapid decline in lung function. Multivariate linear regression models with lung function as the outcome were compared using the likelihood ratio test or the Vuong test, and AUC values for diagnostic and prognostic capabilities were compared using the DeLong test. RESULTS. Texture showed a significantly stronger association with lung function (p < 0.001 vs densitometric measures), a significantly higher diagnostic AUC value (for COPD, 0.696; for Global Initiative for Chronic Obstructive Lung Disease (GOLD) grade 1, 0.648; for GOLD grade 2, 0.768; and for GOLD grade 3, 0.944; p < 0.001 vs densitometric measures), and a higher but not significantly different association with lung function decline. In addition, only texture could predict a rapid decline in lung function (AUC value, 0.538; p < 0.05 vs random guessing). The combination of texture and both densitometric measures strengthened the association with lung function and decline in lung function (p < 0.001 and p < 0.05, respectively, vs texture) but did not improve diagnostic or prognostic performance. CONCLUSION. The present study highlights texture as a promising quantitative CT measure of COPD to use alongside, or even instead of, densitometric measures. Moreover, texture may allow early detection of COPD in subjects who undergo lung cancer screening.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Dinamarca , Densitometria , Feminino , Humanos , Neoplasias Pulmonares/fisiopatologia , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/fisiopatologia , Testes de Função Respiratória , Estudos Retrospectivos
14.
J Immunol ; 200(10): 3372-3382, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29632140

RESUMO

Among HIV-infected individuals, long-term nonprogressor (LTNP) patients experience slow CD4 T cell decline and almost undetectable viral load for several years after primary acquisition of HIV. Type I IFN has been suggested to play a pathogenic role in HIV pathogenesis, and therefore diminished IFN responses may underlie the LTNP phenotype. In this study, we examined the presence and possible immunological role of multiple homozygous single-nucleotide polymorphisms in the stimulator of IFN genes (STING) encoding gene TMEM173 involved in IFN induction and T cell proliferation in HIV LTNP patients. We identified LTNPs through the Danish HIV Cohort and performed genetic analysis by Sanger sequencing, covering the R71H-G230A-R293Q (HAQ) single-nucleotide polymorphisms in TMEM173 This was followed by investigation of STING mRNA and protein accumulation as well as innate immune responses and proliferation following STING stimulation and infection with replication-competent HIV in human blood-derived cells. We identified G230A-R293Q/G230A-R293Q and HAQ/HAQ homozygous TMEM173 variants in 2 out of 11 LTNP patients. None of the 11 noncontrollers on antiretroviral treatment were homozygous for these variants. We found decreased innate immune responses to DNA and HIV as well as reduced STING-dependent inhibition of CD4 T cell proliferation, particularly in the HAQ/HAQ HIV LTNP patients, compared with the age- and gender-matched noncontrollers on antiretroviral treatment. These findings suggest that homozygous HAQ STING variants contribute to reduced inhibition of CD4 T cell proliferation and a reduced immune response toward DNA and HIV, which might result in reduced levels of constitutive IFN production. Consequently, the HAQ/HAQ TMEM173 genotype may contribute to the slower disease progression characteristic of LTNPs.


Assuntos
Infecções por HIV/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Antirretrovirais/uso terapêutico , Linhagem Celular , Estudos de Coortes , Estudos Transversais , Feminino , Genótipo , Células HEK293 , Infecções por HIV/tratamento farmacológico , Sobreviventes de Longo Prazo ao HIV , HIV-1/efeitos dos fármacos , Homozigoto , Humanos , Imunidade Inata/genética , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Masculino , Pessoa de Meia-Idade , Carga Viral/efeitos dos fármacos
15.
BMC Public Health ; 20(1): 664, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32397984

RESUMO

BACKGROUND: The screen-media landscape has changed drastically during the last decade with wide-scale ownership and use of new portable touchscreen-based devices plausibly causing changes in the volume of screen media use and the way children and young people entertain themselves and communicate with friends and family members. This rapid development is not sufficiently mirrored in available tools for measuring children's screen media use. The aim of this study was to develop and evaluate a parent-reported standardized questionnaire to assess 6-10-year old children's multiple screen media use and habits, their screen media environment, and its plausible proximal correlates based on a suggested socio-ecological model. METHODS: An iterative process was conducted developing the SCREENS questionnaire. Informed by the literature, media experts and end-users, a conceptual framework was made to guide the development of the questionnaire. Parents and media experts evaluated face and content validity. Pilot and field testing in the target group was conducted to assess test-retest reliability using Kappa statistics and intraclass correlation coefficients (ICC). Construct validity of relevant items was assessed using pairwise non-parametric correlations (Spearman's). The SCREENS questionnaire is based on a multidimensional and formative model. RESULTS: The SCREENS questionnaire covers six domains validated to be important factors of screen media use in children and comprises 19 questions and 92 items. Test-retest reliability (n = 37 parents) for continuous variables was moderate to substantial with ICC's ranging from 0.67 to 0.90. For relevant nominal and ordinal data, kappa values were all above 0.50 with more than 80% of the values above 0.61 indicating good test-retest reliability. Internal consistency between two different time use variables (from n = 243) showed good correlations with rho ranging from 0.59 to 0.66. Response-time was within 15 min for all participants. CONCLUSIONS: SCREENS-Q is a comprehensive tool to assess children's screen media habits, the screen media environment and possible related correlates. It is a feasible questionnaire with multiple validated constructs and moderate to substantial test-retest reliability of all evaluated items. The SCREENS-Q is a promising tool to investigate children screen media use.


Assuntos
Comportamento Infantil , Meios de Comunicação/estatística & dados numéricos , Comportamentos Relacionados com a Saúde , Tempo de Tela , Comportamento Sedentário , Inquéritos e Questionários/normas , Adulto , Criança , Dinamarca , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
16.
BMC Public Health ; 20(1): 380, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32293374

RESUMO

BACKGROUND: During the recent decade presence of digital media, especially handheld devices, in everyday life, has been increasing. Survey data suggests that children and adults spend much of their leisure on screen media, including use of social media and video services. Despite much public debate on possible harmful effects of such behavioral shifts, evidence from rigorously conducted randomized controlled trials in free-living settings, investigating the efficacy of reducing screen media use on physical activity, sleep, and physiological stress, is still lacking. Therefore, a family and home-based randomized controlled trial - the SCREENS trial - is being conducted. Here we describe in detail the rationale and protocol of this study. METHODS: The SCREENS pilot trial was conducted during the fall of 2018 and spring of 2019. Based on experiences from the pilot study, we developed a protocol for a parallel group randomized controlled trial. The trial is being conducted from May 2019 to ultimo 2020 in 95 families with children 4-14 years recruited from a population-based survey. As part of the intervention family members must handover most portable devices for a 2-week time frame, in exchange for classic mobile phones (not smartphones). Also, entertainment-based screen media use during leisure must be limited to no more than 3 hours/week/person. At baseline and follow-up, 7-day 24-h physical activity will be assessed using two triaxial accelerometers; one at the right hip and one the middle of the right thigh. Sleep duration will be assessed using a single channel EEG-based sleep monitor system. Also, to assess physiological stress (only assessed in adults), parameters of 24-h heart rate variability, the cortisol awakening response and diurnal cortisol slope will be quantified using data sampled over three consecutive days. During the study we will objectively monitor the families' screen media use via different software and hardware monitoring systems. DISCUSSION: Using a rigorous study design with state-of-the-art methodology to assess outcomes and intervention compliance, analyses of data from the SCREENS trial will help answer important causal questions of leisure screen media habits and its short-term influence on physical activity, sleep, and other health related outcomes among children and adults. TRIAL REGISTRATION: NCT04098913 at https://clinicaltrials.gov [20-09-2019, retrospectively registered].


Assuntos
Comportamento do Adolescente , Comportamento Infantil , Exercício Físico , Nível de Saúde , Tempo de Tela , Sono , Estresse Fisiológico , Adolescente , Saúde do Adolescente , Telefone Celular , Criança , Saúde da Criança , Pré-Escolar , Computadores , Feminino , Humanos , Internet , Masculino , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Smartphone , Mídias Sociais , Televisão
17.
BMC Pulm Med ; 20(1): 67, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32188453

RESUMO

BACKGROUND: Interstitial lung abnormalities (ILA) are common in participants of lung cancer screening trials and broad population-based cohorts. They are associated with increased mortality, but less is known about disease specific morbidity and healthcare utilisation in individuals with ILA. METHODS: We included all participants from the screening arm of the Danish Lung Cancer Screening Trial with available baseline CT scan data (n = 1990) in this cohort study. The baseline scan was scored for the presence of ILA and patients were followed for up to 12 years. Data about all hospital admissions, primary healthcare visits and medicine prescriptions were collected from the Danish National Health Registries and used to determine the participants' disease specific morbidity and healthcare utilisation using Cox proportional hazards models. RESULTS: The 332 (16.7%) participants with ILA were more likely to be diagnosed with one of several respiratory diseases, including interstitial lung disease (HR: 4.9, 95% CI: 1.8-13.3, p = 0.008), COPD (HR: 1.7, 95% CI: 1.2-2.3, p = 0.01), pneumonia (HR: 2.0, 95% CI: 1.4-2.7, p <  0.001), lung cancer (HR: 2.7, 95% CI: 1.8-4.0, p <  0.001) and respiratory failure (HR: 1.8, 95% CI: 1.1-3.0, p = 0.03) compared with participants without ILA. These findings were confirmed by increased hospital admission rates with these diagnoses and more frequent prescriptions for inhalation medicine and antibiotics in participants with ILA. CONCLUSIONS: Individuals with ILA are more likely to receive a diagnosis and treatment for several respiratory diseases, including interstitial lung disease, COPD, pneumonia, lung cancer and respiratory failure during long-term follow-up.


Assuntos
Doenças Pulmonares Intersticiais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Admissão do Paciente/estatística & dados numéricos , Idoso , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Pulmão/fisiopatologia , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/epidemiologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico por imagem , Pneumonia/epidemiologia , Modelos de Riscos Proporcionais , Sistema de Registros , Fatores de Risco , Fumar , Tomografia Computadorizada por Raios X
18.
Qual Health Res ; 30(5): 760-771, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31729930

RESUMO

The purpose of this study was to explore the lived experiences, perceptions, and considerations of individuals who declined participation in a randomized clinical trial involving exercise rehabilitation after surgery for lung cancer. An interpretive phenomenological approach was applied comprising interviews with 15 individuals who did not wish to participate in the trial. The findings shed light on a discrepancy between their freedom to act and make decisions and the limitations of having to act in a certain way. The participants found themselves in a gray area between a healthy life and a good life, as influenced by societal norms and taking responsibility for one's own health and rehabilitation. When including patients in rehabilitation after lung cancer, having insight into the underlying narrative on values and the good life, priorities in daily life, social context and the norms embedded in people's self-understanding is crucial.


Assuntos
Neoplasias Pulmonares , Terapia por Exercício , Humanos , Neoplasias Pulmonares/cirurgia , Percepção , Pesquisa Qualitativa
19.
Eur Radiol ; 29(9): 4613-4623, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30673817

RESUMO

OBJECTIVES: To develop and evaluate a fully automatic method to measure diameters of the ascending and descending aorta on non-ECG-gated, non-contrast computed tomography (CT) scans. MATERIAL AND METHODS: The method combines multi-atlas registration to obtain seed points, aorta centerline extraction, and an optimal surface segmentation approach to extract the aorta surface around the centerline. From the extracted 3D aorta segmentation, the diameter of the ascending and descending aorta was calculated at cross-sectional slices perpendicular to the extracted centerline, at the level of the pulmonary artery bifurcation, and at 1-cm intervals up to 3 cm above and below this level. Agreement with manual annotations was evaluated by dice similarity coefficient (DSC) for segmentation overlap, mean surface distance (MSD), and intra-class correlation (ICC) of diameters on 100 CT scans from a lung cancer screening trial. Repeatability of the diameter measurements was evaluated on 617 baseline-one year follow-up CT scan pairs. RESULTS: The agreement between manual and automatic segmentations was good with 0.95 ± 0.01 DSC and 0.56 ± 0.08 mm MSD. ICC between the diameters derived from manual and from automatic segmentations was 0.97, with the per-level ICC ranging from 0.87 to 0.94. An ICC of 0.98 for all measurements and per-level ICC ranging from 0.91 to 0.96 were obtained for repeatability. CONCLUSION: This fully automatic method can assess diameters in the thoracic aorta reliably even in non-ECG-gated, non-contrast CT scans. This could be a promising tool to assess aorta dilatation in screening and in clinical practice. KEY POINTS: • Fully automatic method to assess thoracic aorta diameters. • High agreement between fully automatic method and manual segmentations. • Method is suitable for non-ECG-gated CT and can therefore be used in screening.


Assuntos
Aorta Torácica/anatomia & histologia , Aorta Torácica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Aorta/anatomia & histologia , Aorta/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Estudos Transversais , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes
20.
Physiol Plant ; 166(3): 848-861, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30238999

RESUMO

Plasma membrane H+ -ATPase pumps build up the electrochemical H+ gradients that energize most other transport processes into and out of plant cells through channel proteins and secondary active carriers. In Arabidopsis thaliana, the AUTOINHIBITED PLASMA MEMBRANE H+ -ATPases AHA1, AHA2 and AHA7 are predominant in root epidermal cells. In contrast to other H+ -ATPases, we find that AHA7 is autoinhibited by a sequence present in the extracellular loop between transmembrane segments 7 and 8. Autoinhibition of pump activity was regulated by extracellular pH, suggesting negative feedback regulation of AHA7 during establishment of an H+ gradient. Due to genetic redundancy, it has proven difficult to test the role of AHA2 and AHA7, and mutant phenotypes have previously only been observed under nutrient stress conditions. Here, we investigated root and root hair growth under normal conditions in single and double mutants of AHA2 and AHA7. We find that AHA2 drives root cell expansion during growth but that, unexpectedly, restriction of root hair elongation is dependent on AHA2 and AHA7, with each having different roles in this process.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Membrana Celular/metabolismo , Raízes de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Proteínas de Arabidopsis/genética , Transporte Biológico/genética , Transporte Biológico/fisiologia , Concentração de Íons de Hidrogênio , Mutação , ATPases Translocadoras de Prótons/genética
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