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1.
J Exp Child Psychol ; 238: 105804, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37913679

RESUMO

Our ability to integrate posture with visually demanding tasks is a critical aspect of motor behavior flexibility. When looking at a small object, excessive body movements impair an individual's ability to visually attend to the object. To overcome this problem, we adjust our postural sway to successfully focus on the object. The goal of the current study was to assess whether infants also adjust postural sway when engaged in a challenging visual task. The participants, 19 independently sitting infants (Sitters) and 21 newly independently standing infants (Standers), sat or stood on a force plate while viewing differently sized images displayed on a monitor (smaller images: 8 × 6.5 cm or 3 × 3 cm; larger images: 13 × 16 cm or 13 × 13 cm). Regardless of image size, Standers were less stable than Sitters with larger sway areas and faster sway velocities. Both Sitters and Standers adjusted sway area but not sway velocity, based on image size. Sitters and Standers differed in how they controlled sway dynamics. Standers but not Sitters altered sway dynamics based on image size. Overall, infants used posture-specific adaptive control strategies to make fine-grained adjustments based on image size. The development of the ability to integrate posture with a visually demanding task further emphasizes the capability of advanced complex motor behaviors during infancy, enabling infants to flexibly attend to important aspects of their environment at different postural positions.


Assuntos
Postura , Postura Sentada , Humanos , Lactente , Movimento , Equilíbrio Postural , Atenção
2.
BMC Public Health ; 24(1): 1082, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38637782

RESUMO

BACKGROUND: Much evidence-based physical activity (PA) interventions have been tested and implemented in urban contexts. However, studies that adapt, implement, and evaluate the effectiveness of these interventions in micropolitan rural contexts are needed. The study aimed to evaluate the effectiveness of the Active Ottumwa intervention to promote PA in a micropolitan community. METHODS: Between 2013 - 2019, we implemented Active Ottumwa in a micropolitan setting, and subsequently implemented and evaluated its effectiveness using a Hybrid Type I design. In this paper, we describe the intervention's effectiveness in promoting PA. We collected PA data over 24 months from a cohort of community residents using accelerometers and PA data from two cross-sectional community surveys administered in 2013 and 2018, using the Global Physical Activity Questionnaire. RESULTS: From the cohort, we found significant change in PA over 24 months (P = 0.03) corresponding to a 45-min daily decrease in sedentary activity, a daily increase of 35-min in light PA and 9 min in moderate-to-vigorous PA. There was a statistically significant (P = 0.01) increasing trend at the population-level in the moderate-to-vigorous composition of 7 min between the two cross-sectional assessments (95% CI: 0.1%-1.34%). CONCLUSIONS: The study demonstrates that the adapted evidence-based PA interventions in a micropolitan context is effective.


Assuntos
Exercício Físico , População Rural , Humanos , Estudos Transversais
3.
J Drugs Dermatol ; 23(1): 1274-1277, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206153

RESUMO

BACKGROUND: Keratosis pilaris (KP) is a benign dermatosis consisting of folliculocentric keratotic papules or pustules with surrounding erythema, often on proximal extensor surfaces of extremities. Management strategies for KP largely center on moisturization and exfoliation. Urea, a well-established ingredient in topical skincare, is a component of the natural moisturizing factors with concentration-dependent humectant, emollient, and exfoliative properties.  Given the overlap of urea’s properties and management goals of KP, a 4-week, open-label, noncomparative clinical study was conducted to evaluate a moisturizing cream formulated with 20% urea for use in KP.  Thirty participants aged 18 to 65 years with KP completed this study. After a 5-day washout period, study participants applied a 20% urea cream once daily to areas of KP for 4 weeks. At baseline, 1-week, and 4-week visits, clinical grading of skin texture, adverse event monitoring, and participant satisfaction questionnaires were conducted. After 1 week and 4 weeks of product use, the percent change in skin smoothness/texture from baseline was significant (P≤0.001). Furthermore, after 4 weeks of use, the majority of participants indicated satisfaction with the feel of their skin, as well as improved confidence and decreased embarrassment related to their skin. No significant adverse events were reported. Overall, the results of this study support that 20% urea cream is generally well tolerated and suitable for use in treating KP. J Drugs Dermatol. 2024;23(1):1274-1277.     doi:10.36849/JDD.7806.


Assuntos
Anormalidades Múltiplas , Doença de Darier , Sobrancelhas , Humanos , Emolientes , Emoções , Excipientes , Sobrancelhas/anormalidades , Pele
4.
Health Promot Pract ; : 15248399231221728, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38264839

RESUMO

BACKGROUND: Assessing community and organizational readiness is key to successfully implementing programs. The purpose of this study was to assess the baseline readiness of micropolitan communities to adopt an evidence-based physical activity (PA) intervention by exploring three dimensions: (1) attitudes and current efforts toward prevention, (2) community and organizational climate that facilitates (or impedes) change, and (3) capacity to implement change. METHOD: Data were collected from community leaders in 14 communities through an online survey in June 2021 (n = 149). Data were analyzed in aggregate using descriptive statistics for multiple-choice responses and content analysis for open ended responses. One-way repeated analyses of variance were used to compare mean score differences. RESULTS: In reference to their attitudes prior to the pandemic, respondents said that addressing PA was "somewhat a priority" in their professional positions (M = 2.01, SD = 0.94), their organizations (M = 2.08, SD = 0.91), and their communities (M = 2.28, SD = 0.88). Current PA efforts included statewide initiatives, community sponsored events/clubs, and youth sports leagues. The community climate included both PA facilitators (mainly outdoor PA resources) and barriers (cost, lack of social services, and an unsupportive PA environment). Individual-level capacity (M = 2.94; SD = 1.21) to adopt a PA program was regarded lower than the community's capacity (M = 3.95; SD = 0.82), and perceptions of capacity at the community level improved even more if technical assistance (M = 3.96; SD = 0.84) or financial support (M = 4.12; SD = 0.80) were provided. CONCLUSION: Readiness varied by dimension, suggesting the need for tailored implementation supports including technical assistance and financial support.

5.
Antimicrob Agents Chemother ; 67(5): e0138622, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37071019

RESUMO

Human immunodeficiency virus (HIV) treatment with antiretroviral regimens containing integrase strand transfer inhibitors such as dolutegravir (DTG) and bictegravir (BIC) offers high levels of protection against the development of drug resistance mutations. Despite this, resistance to DTG and BIC can occur through the development of the R263K integrase substitution. Failure with DTG has also been associated with the emergence of the G118R substitution. G118R and R263K are usually found separately but have been reported together in highly treatment-experienced persons who experienced treatment failure with DTG. We used cell-free strand transfer and DNA binding assays and cell-based infectivity, replicative capacity, and resistance assays to characterize the G118R plus R263K combination of integrase mutations. R263K reduced DTG and BIC susceptibility ~2-fold, in agreement with our previous work. Single-cycle infectivity assays showed that G118R and G118R plus R263K conferred ~10-fold resistance to DTG. G118R alone conferred low levels of resistance to BIC (3.9-fold). However, the G118R plus R263K combination conferred high levels of resistance to BIC (33.7-fold), likely precluding the use of BIC after DTG failure with the G118R plus R263K combination. DNA binding, viral infectivity, and replicative capacity of the double mutant were further impaired, compared to single mutants. We propose that impaired fitness helps to explain the scarcity of the G118R plus R263K combination of integrase substitutions in clinical settings and that immunodeficiency likely contributes to its development.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Humanos , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , HIV-1/metabolismo , Substituição de Aminoácidos , Integrase de HIV/genética , Integrase de HIV/metabolismo , Mutação , Compostos Heterocíclicos com 3 Anéis/farmacologia , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Piridonas/farmacologia , DNA/farmacologia , DNA/uso terapêutico , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico
6.
Eur Respir J ; 61(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36265882

RESUMO

BACKGROUND: Abnormal macrophage function caused by dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR) is a critical contributor to chronic airway infections and inflammation in people with cystic fibrosis (PWCF). Elexacaftor/tezacaftor/ivacaftor (ETI) is a new CFTR modulator therapy for PWCF. Host-pathogen and clinical responses to CFTR modulators are poorly described. We sought to determine how ETI impacts macrophage CFTR function, resulting effector functions and relationships to clinical outcome changes. METHODS: Clinical information and/or biospecimens were obtained at ETI initiation and 3, 6, 9 and 12 months post-ETI in 56 PWCF and compared with non-CF controls. Peripheral blood monocyte-derived macrophages (MDMs) were isolated and functional assays performed. RESULTS: ETI treatment was associated with increased CF MDM CFTR expression, function and localisation to the plasma membrane. CF MDM phagocytosis, intracellular killing of CF pathogens and efferocytosis of apoptotic neutrophils were partially restored by ETI, but inflammatory cytokine production remained unchanged. Clinical outcomes including increased forced expiratory volume in 1 s (+10%) and body mass index (+1.0 kg·m-2) showed fluctuations over time and were highly individualised. Significant correlations between post-ETI MDM CFTR function and sweat chloride levels were observed. However, MDM CFTR function correlated with clinical outcomes better than sweat chloride. CONCLUSION: ETI is associated with unique changes in innate immune function and clinical outcomes.


Assuntos
Fibrose Cística , Humanos , Fibrose Cística/tratamento farmacológico , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Cloretos/metabolismo , Agonistas dos Canais de Cloreto/uso terapêutico , Mutação , Macrófagos/metabolismo
7.
BMC Public Health ; 23(1): 1637, 2023 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-37633898

RESUMO

BACKGROUND: Last responders constitute an occupational category that includes all those that are involved in the postmortem care of deceased persons and their families. Last responders are exposed to several categories of work-related stressors that affect their health and well-being. COVID-19 exacerbated these stressors. Research to understand the consequences of COVID-19 on the health and wellbeing of last responders is nascent. This study aimed to assess COVID-19 related stress, coping and wellbeing among last responders in the United States. METHODS: We conducted a national cross-sectional survey of last responders in July through September of 2020. The survey measured wellbeing, stress, coping, and stigma; COVID-19 experiences, and socio-demographics. A ridge regression model was fit for the outcome variables. RESULTS: Analysis was conducted on 366 respondents from 43 states. Respondents were male (55.4%), age 50 + (57.4%), and White non-Hispanic (90.3%); 54% reported moderate-high stress and 41% endorsed mild-severe anxiety. Seventy-seven percent had experienced at least one form of stigma related to their occupation. Variables associated with higher perceived stress and anxiety included gender (female), shorter length of employment, perceiving a higher impact from COVID-19 on everyday life, and increased perceived stigma. CONCLUSIONS: Last responders are a critical part of the health care system. Throughout this pandemic, last responders have been frequently ignored and not prioritized for protection and support. Interventions to support last responders cope with stress, and to decrease anxiety are urgently needed. There is also a critical need to challenge community stigma towards last responders.


Assuntos
COVID-19 , Feminino , Masculino , Humanos , Pessoa de Meia-Idade , Estudos Transversais , COVID-19/epidemiologia , Emoções , Ansiedade/epidemiologia , Transtornos de Ansiedade
8.
Proc Natl Acad Sci U S A ; 117(33): 20211-20222, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747554

RESUMO

The giant tiger prawn (Penaeus monodon) is a decapod crustacean widely reared for human consumption. Currently, viruses of two distinct lineages of parvoviruses (PVs, family Parvoviridae; subfamily Hamaparvovirinae) infect penaeid shrimp. Here, a PV was isolated and cloned from Vietnamese P. monodon specimens, designated Penaeus monodon metallodensovirus (PmMDV). This is the first member of a third divergent lineage shown to infect penaeid decapods. PmMDV has a transcription strategy unique among invertebrate PVs, using extensive alternative splicing and incorporating transcription elements characteristic of vertebrate-infecting PVs. The PmMDV proteins have no significant sequence similarity with other PVs, except for an SF3 helicase domain in its nonstructural protein. Its capsid structure, determined by cryoelectron microscopy to 3-Å resolution, has a similar surface morphology to Penaeus stylirostris densovirus, despite the lack of significant capsid viral protein (VP) sequence similarity. Unlike other PVs, PmMDV folds its VP without incorporating a ßA strand and displayed unique multimer interactions, including the incorporation of a Ca2+ cation, attaching the N termini under the icosahedral fivefold symmetry axis, and forming a basket-like pentamer helix bundle. While the PmMDV VP sequence lacks a canonical phospholipase A2 domain, the structure of an EDTA-treated capsid, determined to 2.8-Å resolution, suggests an alternative membrane-penetrating cation-dependent mechanism in its N-terminal region. PmMDV is an observed example of convergent evolution among invertebrate PVs with respect to host-driven capsid structure and unique as a PV showing a cation-sensitive/dependent basket structure for an alternative endosomal egress.


Assuntos
Evolução Biológica , Proteínas do Capsídeo/genética , Densovirus/genética , Penaeidae/virologia , Animais , Regulação Viral da Expressão Gênica , Genoma Viral
9.
Int J Mol Sci ; 24(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894961

RESUMO

Cowpea (Vigna unguiculata (L.) Walp.) is a diploid legume crop used for human consumption, feed for livestock, and cover crops. Earlier reports have shown that salinity has been a growing threat to cowpea cultivation. The objectives of this study were to conduct a genome-wide association study (GWAS) to identify SNP markers and to investigate candidate genes for salt tolerance in cowpea. A total of 331 cowpea genotypes were evaluated for salt tolerance by supplying a solution of 200 mM NaCl in our previous work. The cowpea panel was genotyped using a whole genome resequencing approach, generating 14,465,516 SNPs. Moreover, 5,884,299 SNPs were used after SNP filtering. GWAS was conducted on a total of 296 cowpea genotypes that have high-quality SNPs. BLINK was used for conducting GWAS. Results showed (1) a strong GWAS peak on an 890-bk region of chromosome 2 for leaf SPAD chlorophyll under salt stress in cowpea and harboring a significant cluster of nicotinamide adenine dinucleotide (NAD) dependent epimerase/dehydratase genes such as Vigun02g128900.1, Vigun02g129000.1, Vigun02g129100.1, Vigun02g129200.1, and Vigun02g129500.1; (2) two GWAS peaks associated with relative tolerance index for chlorophyll were identified on chromosomes 1 and 2. The peak on chromosome 1 was defined by a cluster of 10 significant SNPs mapped on a 5 kb region and was located in the vicinity of Vigun01g086000.1, encoding for a GATA transcription factor. The GWAS peak on chromosome 2 was defined by a cluster of 53 significant SNPs and mapped on a 68 bk region of chromosome 2, and (3) the highest GWAS peak was identified on chromosome 3, and this locus was associated with leaf score injury. This peak was within the structure of a potassium channel gene (Vigun03g144700.1). To the best of our knowledge, this is one the earliest reports on the salt tolerance study of cowpea using whole genome resequencing data.


Assuntos
Vigna , Humanos , Vigna/genética , Plântula/genética , Estudo de Associação Genômica Ampla , Tolerância ao Sal/genética , Clorofila
10.
J Minim Invasive Gynecol ; 29(2): 284-290, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34433103

RESUMO

STUDY OBJECTIVE: To compare the recurrence rate, post-treatment American Fertility Society (AFS) score, ongoing pregnancy rate, and endometrial thickness of 3 secondary prevention therapies in preventing recurrent intrauterine adhesions (IUAs) and increasing pregnancy rates in infertile women after hysteroscopic adhesiolysis. DESIGN: A retrospective study. SETTING: A private fertility hospital. PATIENTS: A total of 200 consecutive infertile women, with the desire to have a baby and were diagnosed as having IUAs detected by hysterosalpingogram, who underwent hysteroscopic adhesiolysis for IUAs from January, 2018 to May, 2020. INTERVENTIONS: Women who underwent hysteroscopic adhesiolysis received hormone therapy, and one of the 3 secondary preventions: hyaluronic acid (HA) gel alone, intrauterine devices (IUDs) alone, or HA gel + IUD. MEASUREMENTS AND MAIN RESULTS: Of the 200 women included in the final analysis, 121 received HA alone, 59 were treated with IUD alone, and 20 received HA gel + IUD combination. The mean post-treatment AFS score for IUAs was significantly lower in the HA gel + IUD group than the HA alone or the IUD alone groups (adjusted p = .01 and p = .02, respectively). Multivariable analysis revealed a significantly lower recurrence rate in the women after treatment with HA gel + IUD than HA alone (adjusted odds ratio, 0.19; 95% credible interval [CreI], 0.03-0.88). Women treated with HA gel + IUD also had reduced post-treatment AFS scores compared with HA alone (ß coefficients, -0.83; 95% CreI, -1.64 to -0.01). For ongoing pregnancy rates after in vitro fertilization, the adjusted odds ratio for HA gel + IUD vs HA alone was 2.03 (95% CreI, 0.44-11.00) and for IUD alone vs HA alone was 1.13 (95% CreI, 0.41-3.29), indicating nonsignificant differences. There were no differences observed in endometrial thickness on the day of embryo transfer among the 3 groups. CONCLUSION: The investigation of the primary outcome in reducing the recurrence rate IUA after treatment demonstrated that a combination of HA gel + IUD provides greater prevention of recurrent IUAs and may decrease post-treatment AFS scores for infertile women undergoing hysteroscopic adhesiolysis. However, for the secondary outcome of increasing pregnancy rates, there was no improvement in the ongoing pregnancy rates after in vitro fertilization.


Assuntos
Infertilidade Feminina , Dispositivos Intrauterinos , Doenças Uterinas , Feminino , Humanos , Ácido Hialurônico/uso terapêutico , Histeroscopia/efeitos adversos , Infertilidade Feminina/etiologia , Infertilidade Feminina/prevenção & controle , Infertilidade Feminina/cirurgia , Dispositivos Intrauterinos/efeitos adversos , Gravidez , Estudos Retrospectivos , Aderências Teciduais/etiologia , Aderências Teciduais/prevenção & controle , Aderências Teciduais/cirurgia , Doenças Uterinas/cirurgia
11.
J Antimicrob Chemother ; 76(3): 639-647, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33184634

RESUMO

OBJECTIVES: The development of HIV drug resistance against the integrase strand transfer inhibitor dolutegravir is rare. We report here the transient detection, by near full-genome ultradeep sequencing, of minority HIV-1 subtype B variants bearing the S153F and R263K integrase substitutions in the proviral DNA from blood cells of one patient who successfully initiated dolutegravir-based ART, over 24 weeks. Our objective was to study the effects of these substitutions. METHODS: Strand transfer and DNA-binding activities of recombinant integrase proteins were measured in cell-free assays. Cell-based resistance, infectivity and replicative capacities were measured using molecular clones. Structural modelling was performed to understand experimental results. RESULTS: R263K emerged first, followed by the addition of S153F at Week 12. By Week 24, both mutations remained present, but at lower prevalence. We confirmed the coexistence of S153F and R263K on single viral genomes. Combining S153F or S153Y with R263K decreased integration and viral replicative capacity and conferred high levels of drug resistance against all integrase inhibitors. Alone, S153Y and S153F did little to infectivity or dolutegravir resistance. We identified altered DNA binding as a mechanism of resistance. The patient remained with undetectable viral loads at all timepoints. CONCLUSIONS: Drug-resistant minority variants have often been reported under suppressive ART. Our study adds to these observations by unravelling a progression towards higher levels of resistance through a novel pathway despite continuous undetectable viral loads. Poorly replicative HIV drug-resistant minority proviral variants did not compromise viral suppression in one individual treated with dolutegravir.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Substituição de Aminoácidos , DNA , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Integrase de HIV/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , Compostos Heterocíclicos com 3 Anéis/farmacologia , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Mutação , Oxazinas/farmacologia , Piperazinas/farmacologia , Provírus/genética , Piridonas/farmacologia
12.
Bull World Health Organ ; 99(1): 50-61, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33658734

RESUMO

OBJECTIVE: To investigate factors associated with survival after out-of-hospital cardiac arrest in Viet Nam. METHODS: We did a multicentre prospective observational study of people (> 18 years) presenting with out-of-hospital cardiac arrest (not caused by trauma) to three tertiary hospitals in Viet Nam from February 2014 to December 2018. We collected data on characteristics, management and outcomes of patients with out-of-hospital cardiac arrest and compared these data by type of transportation to hospital and survival to hospital admission. We assessed factors associated with survival to admission to and discharge from hospital using logistic regression analysis. FINDINGS: Of 590 eligible people with out-of-hospital cardiac arrest, 440 (74.6%) were male and the mean age was 56.1 years (standard deviation: 17.2). Only 24.2% (143/590) of these people survived to hospital admission and 14.1% (83/590) survived to hospital discharge. Most cardiac arrests (67.8%; 400/590) occurred at home, 79.4% (444/559) were witnessed by bystanders and 22.3% (124/555) were given cardiopulmonary resuscitation by a bystander. Only 8.6% (51/590) of the people were taken to hospital by the emergency medical services and 32.2% (49/152) received pre-hospital defibrillation. Pre-hospital defibrillation (odds ratio, OR: 3.90; 95% confidence interval, CI: 1.54-9.90) and return of spontaneous circulation in the emergency department (OR: 2.89; 95% CI: 1.03-8.12) were associated with survival to hospital admission. Hypothermia therapy during post-resuscitation care was associated with survival to discharge (OR: 5.44; 95% CI: 2.33-12.74). CONCLUSION: Improvements are needed in the emergency medical services in Viet Nam such as increasing bystander cardiopulmonary resuscitation and public access defibrillation, and improving ambulance and post-resuscitation care.


Assuntos
Parada Cardíaca Extra-Hospitalar/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Transporte de Pacientes , Vietnã/epidemiologia
13.
J Phys Chem A ; 125(29): 6332-6347, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34270256

RESUMO

Metal binding affinities play a vital role in medicinal, biological, and industrial applications. In particular, metal cation-amino acid (AA) interactions contribute to protein stability such that analyzing analogous prototypical interactions is important. Here, we present a full description of the interactions of sodium cations (Na+) and six aliphatic amino acids (AA), where AA = glycine (Gly), alanine (Ala), homoalanine (hAla), valine (Val), leucine (Leu), and isoleucine (Ile). Experimentally, these interactions are evaluated using threshold collision-induced dissociation carried out in a guided ion beam tandem mass spectrometer, allowing for the determination of the kinetic-energy-dependent behavior of Na+-AA dissociation. Analysis of these dissociation cross sections, after accounting for multiple ion-molecule collisions, internal energy of reactant ions, and unimolecular decay rates, allows the determination of absolute Na+-AA bond dissociation energies (BDEs) in kJ/mol of Gly (164.0), Ala (166.9), hAla (167.9), Val (172.7), Leu (173.7), and Ile (174.6). These are favorably compared to quantum chemical calculations conducted at the B3LYP, B3P86, MP2(full), B3LYP-GD3BJ, and M06-2X levels of theory. Our combination of structural and energetic analyses provides information regarding the specific factors responsible for Na+ interactions with amino acids. Specifically, we find that the BDEs increase linearly with increasing polarizability of the amino acid.


Assuntos
Aminoácidos/metabolismo , Sódio/metabolismo , Aminoácidos/química , Entropia , Ligantes , Modelos Químicos , Conformação Molecular , Sódio/química
14.
Plant Cell Physiol ; 61(5): 1005-1018, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32154880

RESUMO

MYB-bHLH-WDR (MBW) transcription factor (TF) complexes regulate Arabidopsis seed coat development including mucilage and tannin biosynthesis. The R2R3 MYBs MYB5, MYB23 and TRANSPARENT TESTA2 (TT2) participate in the MBW complexes with the WD-repeat protein TRANSPARENT TESTA GLABRA1 (TTG1). These complexes regulate GLABRA2 (GL2) and TTG2 expression in developing seeds. Microarray transcriptome analysis of ttg1-1- and wild-type (Ler) developing seeds identified 246 TTG1-regulated genes, which include all known metabolic genes of the tannin biosynthetic pathway. The first detailed TTG1-dependent metabolic pathways could be proposed for the biosynthesis of mucilage, jasmonic acid (JA) and cuticle including wax ester in developing seeds. We also assigned many known and previously uncharacterized genes to the activation/inactivation of hormones, plant immunity and nutrient transport. The promoters of six cuticle pathway genes were active in developing seeds. Expression of 11 genes was determined in the developing seeds of the combinatorial mutants of MYB5, MYB23 and TT2, and in the combinatorial mutants of GL2, HOMEODOMAIN GLABROUS2 (HDG2) and TTG2. These six TFs positively co-regulated the expression of four repressor genes while three of the six TFs repressed the wax biosynthesis genes examined, suggesting that the three TFs upregulate the expression of these repressor genes, which, in turn, repress the wax biosynthesis genes. Chromatin immunoprecipitation analysis identified 21 genes directly regulated by MYB5 including GL2, HDG2, TTG2, four repressor genes and various metabolic genes. We propose a multi-tiered regulatory mechanism by which MBWs regulate tannin, mucilage, JA and cuticle biosynthetic pathways.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Vias Biossintéticas , Sementes/metabolismo , Fatores de Transcrição/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/embriologia , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Sequência de Bases , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Lipídeos de Membrana , Modelos Biológicos , Oxilipinas/metabolismo , Epiderme Vegetal/metabolismo , Imunidade Vegetal/efeitos dos fármacos , Mucilagem Vegetal/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Transdução de Sinais/genética , Taninos/metabolismo , Ceras/metabolismo
15.
J Virol ; 93(2)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30381490

RESUMO

Drug resistance remains a major concern for human immunodeficiency virus (HIV) treatment. To date, very few resistance mutations have emerged in first-line combination therapy that includes the integrase strand transfer inhibitor (INSTI) dolutegravir (DTG). In vitro, DTG selects for several primary mutations that induce low-level DTG resistance; secondary mutations, while increasing the level of resistance, however, further impair replication fitness, which raised the idea that DTG monotherapy may be feasible. The simian immunodeficiency virus (SIV) rhesus macaque model of HIV infection can be useful to explore this concept. Nine macaques were infected with virulent SIVmac251 and started on DTG monotherapy during either acute (n = 2) or chronic infection (n = 7). Within 4 weeks of treatment, all animals demonstrated a reduction in viremia of 0.8 to 3.5 log RNA copies/ml plasma. Continued treatment led to overall sustained benefits, but the outcome after 10 to 50 weeks of treatment was highly variable and ranged from viral rebound to near pretreatment levels to sustained suppression, with viremia being 0.5 to 5 logs lower than expected based on pretreatment viremia. A variety of mutations previously described to confer low-level resistance of HIV-1 to DTG or other INSTI were detected, and these were sometimes followed by mutations believed to be compensatory. Some mutations, such as G118R, previously shown to severely impair the replication capacity in vitro, were associated with more sustained virological and immunological benefits of continued DTG therapy, while other mutations, such as E92Q and G140A/Q148K, were associated with more variable outcomes. The observed variability of the outcomes in macaques warrants avoidance of DTG monotherapy in HIV-infected people.IMPORTANCE A growing number of anti-HIV drug combinations are effective in suppressing virus replication in HIV-infected persons. However, to reduce their cost and risk for toxicity, there is considerable interest in simplifying drug regimens. A major concern with single-drug regimens is the emergence of drug-resistant viral mutants. It has been speculated that DTG monotherapy may be a feasible option, because DTG may have a higher genetic barrier for the development of drug resistance than other commonly used antiretrovirals. To explore treatment initiation with DTG monotherapy, we started SIV-infected macaques on DTG during either acute or chronic infection. Although DTG initially reduced virus replication, continued treatment led to the emergence of a variety of viral mutations previously described to confer low-level resistance of HIV-1 to DTG, and this was associated with variable clinical outcomes. This unpredictability of mutational pathways and outcomes warns against using DTG monotherapy as initial treatment for HIV-infected people.


Assuntos
Inibidores de Integrase de HIV/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores de Integrase de HIV/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Macaca mulatta , Mutação , Oxazinas , Piperazinas , Piridonas , RNA Viral/sangue , RNA Viral/efeitos dos fármacos , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/patogenicidade , Resultado do Tratamento
16.
J Med Virol ; 91(7): 1182-1190, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30801742

RESUMO

Studies aimed at repurposing existing drugs revealed that some antimalarial compounds possess anti-Zika virus (anti-ZIKV) activity. Here, we further tested 14 additional antimalarial drugs and their metabolites or analogs for anti-ZIKV activity using a phenotypic screening approach. We identified four compounds with varying anti-ZIKV activity, including a metabolite of amodiaquine termed desethylamodiaquine (DAQ) and N-desethylchloroquine (DECQ), a metabolite of chloroquine, which both exhibited low micromolar effective concentrations against three different ZIKV strains. Two other compounds termed dihydroartemisinin (DHA) and quinidine (QD) exhibited only partial inhibition of ZIKV replication. Characterization of the inhibitory mechanisms of DAQ and DECQ showed that both drugs target the entry step as well as postentry events of the viral replication cycle. These hits represent attractive starting points for future optimization of new anti-ZIKV drug candidates derived from antimalarial drugs and their analogs.


Assuntos
Antimaláricos/farmacologia , Antivirais/farmacologia , Reposicionamento de Medicamentos , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Animais , Antimaláricos/metabolismo , Antivirais/isolamento & purificação , Linhagem Celular , Chlorocebus aethiops , Culicidae/citologia , Células Vero , Zika virus/fisiologia
17.
J Infect Dis ; 218(5): 688-697, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29617822

RESUMO

Background: A high genetic barrier to resistance to the integrase strand transfer inhibitor (INSTI) dolutegravir has been reported in vitro and in vivo. We describe the dynamics of INSTI resistance-associated mutations (INSTI-RAMs) and mutations in the 3'-polypurine tract (3'-PPT) in relation to virologic failure (VF) observed in the randomized Dolutegravir as Maintenance Monotherapy for HIV-1 study (DOMONO, NCT02401828). Methods: From 10 patients with VF, plasma samples were collected before the start of cART and during VF, and were used to generate Sanger sequences of integrase, the 5' terminal bases of the 3' long terminal repeat (LTR), and the 3'-PPT. Results: Median human immunodeficiency virus RNA load at VF was 3490 copies/mL (interquartile range 1440-4990 copies/mL). INSTI-RAMs (S230R, R263K, N155H, and E92Q+N155H) were detected in 4 patients, no INSTI-RAMs were detected in 4 patients, and sequencing of the integrase gene was unsuccessful in 2 patients. The time to VF ranged from 4 weeks to 72 weeks. In 1 patient, mutations developed in the highly conserved 3'-PPT. No changes in the terminal bases of the 3'-LTR were observed. Conclusions: The genetic barrier to resistance is too low to justify dolutegravir maintenance monotherapy because single INSTI-RAMs are sufficient to cause VF. The large variation in time to VF suggests that stochastic reactivation of a preexisting provirus containing a single INSTI-RAM is the mechanism for failure. Changes in the 3'-PPT point to a new dolutegravir resistance mechanism in vivo. Clinical Trials Registration: NCT02401828.


Assuntos
Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores de Integrase de HIV/administração & dosagem , HIV-1/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Mutação , Adulto , Feminino , HIV-1/isolamento & purificação , Humanos , Quimioterapia de Manutenção/métodos , Masculino , Pessoa de Meia-Idade , Oxazinas , Piperazinas , Piridonas , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sequência de DNA , Falha de Tratamento , Carga Viral
18.
J Infect Dis ; 218(5): 698-706, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29617824

RESUMO

Background: Dolutegravir (DTG) is an integrase strand-transfer inhibitor (INSTI) used for treatment of human immunodeficiency virus (HIV)-infected individuals. Owing to its high genetic barrier to resistance, DTG has been clinically investigated as maintenance monotherapy to maintain viral suppression and to reduce complication and healthcare costs. Our study aims to explain the underlying mechanism related to the emergence of a S230R substitution in patients who experienced virologic failure while using DTG monotherapy. Methods: We evaluated the effect of the S230R substitution in regard to integrase enzyme activity, viral infectivity, replicative capacity, and susceptibility to different INSTIs by biochemical and cell-based assays. Results: The S230R substitution conferred a 63% reduction in enzyme efficiency. S230R virus was 1.29-fold less infectious than wild-type virus but could replicate in PM1 cells without significant delay. Resistance levels against DTG, cabotegravir, raltegravir, and elvitegravir in tissue culture were 3.85-, 3.72-, 1.52-, and 1.21-fold, respectively, in virus with the S230R substitution. Conclusions: Our data indicate that the S230R substitution is comparable to the previously reported R263K substitution in some respects. Virologic failure during DTG monotherapy can occur through the development of the S230R or R263K mutation, without the need for high-level DTG resistance.


Assuntos
Substituição de Aminoácidos , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , HIV/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Carga Viral , HIV/genética , HIV/crescimento & desenvolvimento , HIV/isolamento & purificação , Integrase de HIV/genética , Integrase de HIV/metabolismo , Humanos , Quimioterapia de Manutenção/métodos , Testes de Sensibilidade Microbiana , Mutação de Sentido Incorreto , Oxazinas , Piperazinas , Piridonas , Falha de Tratamento , Replicação Viral
19.
Theor Appl Genet ; 131(11): 2287-2298, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30069595

RESUMO

KEY MESSAGE: Evidence that supports a relation between AOX expression and improvement in plant height, internode length, and total leaf area under cool temperature is shown. Cell expansion and elongation appear to be enhanced when AOX expression was increased. Cotton growth is sensitive to cool temperature during germination and early seedling development. Delayed emergence, seedling damage, and increased risk to disease are common. Late seasonal cool weather is a major factor limiting the consistent production of high-quality cotton lint in West Texas. Alternative oxidase functions in the inner membrane of the mitochondria via an alternative respiration pathway and serves as a multifunctional system for amelioration of abiotic and biotic stresses. Cotton seedling emergence and growth exposed to cool temperatures was examined in plants with enhanced AOX expression. Thirteen T1 seed lines showed 3 to 1 segregation for the T-DNA containing the tobacco AOX1 gene. Two over-expressing, single-copy, homozygous AOX lines (94-20T and 66-6T) and Null line (94-3N) were selected for examination. The transcript levels were ≈ 2 to 6 fold higher in the AOX lines compared to those of the Null line and wild-type in stem, leaf, root and boll tissues. The research examined the hypothesis that transgenic cotton with enhanced AOX expression will have enhanced growth traits under suboptimal cool temperatures. Improved plant height, internode length, plant height and internode length from second node, and total leaf area under cool temperatures were observed in AOX over-expression lines. This may be attributed to improved cell expansion and elongation characteristics in the AOX line.


Assuntos
Crescimento Celular , Temperatura Baixa , Gossypium/genética , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas , Gossypium/crescimento & desenvolvimento , Proteínas Mitocondriais/genética , Oxirredutases/genética , Células Vegetais/enzimologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plântula/genética , Nicotiana/enzimologia , Nicotiana/genética
20.
J Invertebr Pathol ; 147: 23-36, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32781498

RESUMO

A wide spectrum of invertebrates is susceptible to various single-stranded DNA viruses. Their relative simplicity of replication and dependence on actively dividing cells makes them highly pathogenic for many invertebrates (Hexapoda, Decapoda, etc.). We present their taxonomical classification and describe the evolutionary relationships between various groups of invertebrate-infecting viruses, their high degree of recombination, and their relationship to viruses infecting mammals or other vertebrates. They share characteristics of the viruses within the various families, including structure of the virus particle, genome properties, and gene expression strategy.

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