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Zygnematophyceae are the algal sisters of land plants. Here we sequenced four genomes of filamentous Zygnematophyceae, including chromosome-scale assemblies for three strains of Zygnema circumcarinatum. We inferred traits in the ancestor of Zygnematophyceae and land plants that might have ushered in the conquest of land by plants: expanded genes for signaling cascades, environmental response, and multicellular growth. Zygnematophyceae and land plants share all the major enzymes for cell wall synthesis and remodifications, and gene gains shaped this toolkit. Co-expression network analyses uncover gene cohorts that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular chassis that balances environmental response and growth modulation across more than 600 million years of streptophyte evolution.

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Vimentin has been reported to play diverse roles in cell processes such as spreading, migration, cell–matrix adhesion, and fibrotic transformation. Here, we assess how vimentin impacts cell spreading, morphology, and myofibroblast transformation of human corneal fibroblasts. Overall, although knockout (KO) of vimentin did not dramatically impact corneal fibroblast spreading and mechanical activity (traction force), cell elongation in response to PDGF was reduced in vimentin KO cells as compared to controls. Blocking vimentin polymerization using Withaferin had even more pronounced effects on cell spreading and also inhibited cell-induced matrix contraction. Furthermore, although absence of vimentin did not completely block TGFβ-induced myofibroblast transformation, the degree of transformation and amount of αSMA protein expression was reduced. Proteomics showed that vimentin KO cells cultured in TGFβ had a similar pattern of protein expression as controls. One exception included periostin, an ECM protein associated with wound healing and fibrosis in other cell types, which was highly expressed only in Vim KO cells. We also demonstrate for the first time that LRRC15, a protein previously associated with myofibroblast transformation of cancer-associated fibroblasts, is also expressed by corneal myofibroblasts. Interestingly, proteins associated with LRRC15 in other cell types, such as collagen, fibronectin, β1 integrin and α11 integrin, were also upregulated. Overall, our data show that vimentin impacts both corneal fibroblast spreading and myofibroblast transformation. We also identified novel proteins that may regulate corneal myofibroblast transformation in the presence and/or absence of vimentin.

Abstract Background HIV self-testing (HIVST) has shown the potential for reaching people with heightened vulnerability to HIV, including young sexual minority men (YSMM), yet implementation of HIVST among YSMM aged 17–24 is scarce as a prevention method. Moreover, despite the consistent finding that offering HIVST increases HIV testing rates, barriers remain that need to be reduced in order to maximize the potential of this biomedical technology. Such information is necessary to direct implementation efforts to increase HIVST among YSMM, including HIV counseling and linkage to care. The current study was therefore intended to investigate perspectives for HIVST among YSMM and how HIVST can be marketed to increase implementation. Methods Between March and September 2020, we enrolled 41 YSMM to participate in one of nine online synchronous focus group discussions about their general experience with HIV preventive services. Guided by the Consolidated Framework (CFIR) for Implementation Research, we explored YSMM perspectives on facilitators and barriers to HIVST implementation. Data were analyzed using a deductive thematic content analysis approach. Results Many participants had never used HIVST before their participation in this study (n = 30; 73.2%). Qualitative results exhibited a variety of implementation determinants across the five CFIR 2.0 domains. Barriers included concerns about the format in which the testing materials would be provided (i.e., nature of packaging) and about the method in which the sample would need to be collected, particularly for those who had the testing kit mailed to their home address. These reservations were nested in the fear of unwanted disclosure of their sexual behavior, namely among the respondents who had to cohabitate with family due to the COVID-19 pandemic. Participants also discussed the limited local resources for HIVST. Many participants suggested programs that could be implemented to support HIVST, such as collaborations with trusted community agencies. Conclusions Understanding YSMM’ perspectives of HIVST may help identify implementation deficiencies within the delivery system and aid the development of implementation strategies to promote reach of HIVST.

Abstract Intramuscular cabotegravir for long-acting injectable HIV pre-exposure prophylaxis (i.e., LAI-PrEP) was approved by the U.S. FDA in 2021. We sought to explore LAI-PrEP decision-making among a nationwide sample of young sexual minority men (YSMM) 17–24 years old. In 2020, HIV-negative/unknown YSMM (n = 41) who met CDC criteria for PrEP were recruited online to participate in synchronous online focus groups eliciting preferences and opinions about LAI-PrEP, as well as the impact of a potential self-administered option. Data were analyzed using inductive and deductive thematic analysis with constant comparison. Preferences and decision-making about LAI-PrEP varied widely among YSMM, with participants frequently comparing LAI-PrEP to oral PrEP regimens. We identified five key themes related to LAI-PrEP decision-making including concerns about adherence to PrEP dosing and clinic appointments, awareness and knowledge of PrEP safety and efficacy data, comfort with needles, minimizing PrEP stigma, and considerations of self-administration. YSMM acknowledged more PrEP options as beneficial to supporting uptake and persistence.

Summary Hydrogen is a clean alternative to fossil fuels. It has applications for electricity generation and transportation and is used for the manufacturing of ammonia and steel. However, today, H2 is almost exclusively produced from coal and natural gas. As such, methods to produce H2 that do not use fossil fuels need to be developed and adopted. The biological manufacturing of H2 may be one promising solution as this process is clean and renewable. Hydrogen is produced biologically via enzymes called hydrogenases. There are three classes of hydrogenases namely [FeFe], [NiFe] and [Fe] hydrogenases. The [FeFe] hydrogenase HydA1 from the model unicellular algae Chlamydomonas reinhardtii has been studied extensively and belongs to the A1 subclass of [FeFe] hydrogenases that have the highest turnover frequencies amongst hydrogenases (21,000 ± 12,000 H2 s−1 for CaHydA from Clostridium acetobutyliticum). Yet to date, limitations in C. reinhardtii H2 production pathways have hampered commercial scale implementation, in part due to O2 sensitivity of hydrogenases and competing metabolic pathways, resulting in low H2 production efficiency. Here, we describe key processes in the biogenesis of HydA1 and H2 production pathways in C. reinhardtii. We also summarize recent advancements of algal H2 production using synthetic biology and describe valuable tools such as high‐throughput screening (HTS) assays to accelerate the process of engineering algae for commercial biological H2 production.

Objective: Seventy percent of Fuchs’ endothelial corneal dystrophy (FECD) cases are caused by an intronic trinucleotide repeat expansion in the transcription factor 4 gene (TCF4). The objective of this study was to characterize the corneal subbasal nerve plexus and corneal haze in patients with FECD with (RE+) and without the trinucleotide repeat expansion (RE−) and to assess the correlation of these parameters with disease severity. Design: Cross-sectional, single-center study. Participants: Fifty-two eyes of 29 subjects with a modified Krachmer grade of FECD severity from 1 to 6 were included in the study. Fifteen of the 29 subjects carried an expanded TCF4 allele length of ≥ 40 cytosine-thymine-guanine repeats (RE+). Main Outcomes Measures: In vivo confocal microscopy assessments of corneal nerve fiber length (CNFL), corneal nerve branch density, corneal nerve fiber density (CNFD), and anterior corneal stromal backscatter (haze); Scheimpflug tomography densitometry measurements of haze in anterior, central, and posterior corneal layers. Results: Using confocal microscopy, we detected a negative correlation between FECD severity and both CNFL and CNFD in the eyes of RE+ subjects (Spearman ρ = −0.45, P = 0.029 and ρ = −0.62, P = 0.0015, respectively) but not in the eyes of RE− subjects. Additionally, CNFD negatively correlated with the repeat length of the expanded allele in the RE+ subjects (Spearman ρ = −0.42, P = 0.038). We found a positive correlation between anterior stromal backscatter and severity in both the RE+ and RE− groups (ρ = 0.60, P = 0.0023 and ρ = 0.44, P = 0.024, respectively). The anterior, central, and posterior Scheimpflug densitometry measurements also positively correlated with severity in both the RE+ and RE− groups (P = 5.5 × 10−5, 2.5 × 10−4, and 2.9 × 10−4, respectively, after adjusting for the expansion status in a pooled analysis. However, for patients with severe FECD (Krachmer grades 5 and 6), the posterior densitometry measurements were higher in the RE+ group than in the RE− group (P < 0.05). Conclusions: Loss of corneal nerves in FECD supports the classification of the TCF4 trinucleotide repeat expansion disorder as a neurodegenerative disease. Haze in the anterior, central, and posterior cornea correlate with severity, irrespective of the genotype. Quantitative assessments of corneal nerves and corneal haze may be useful to gauge and monitor FECD disease severity in RE+ patients.

BackgroundHIV disproportionately affects sexual minority men (SMM) in the United States. ObjectiveWe sought to determine past HIV postexposure prophylaxis (PEP) use and current and prior pre-exposure prophylaxis (PrEP) use among a web-based sample of cisgender and transgender men who have sex with men. MethodsIn 2019, HIV-negative and unknown status SMM (n=63,015) were recruited via geosocial networking apps, social media, and other web-based venues to participate in a brief eligibility screening survey. Individuals were asked about past PEP use and current and prior PrEP use. We examined associations of demographics, socioeconomic indicators, and recent club drug use with PEP and PrEP use, as well as the association between past PEP use and current and prior PrEP use using generalized linear models and multinomial logistic regression. Statistical significance was considered at P

Introduction: A large percentage of people who inject drugs (PWID) are living with HIV. Yet, rates of HIV pre-exposure prophylaxis (PrEP) use among PWID remain low. Stigma surrounding substance use and PWID have been identified as potential barriers to PrEP. This study examined healthcare providers’ concerns regarding PWID and willingness to prescribe PrEP to PWID. Methods: An online, cross-sectional survey of a diverse group of healthcare providers in the 10 U.S. cities with the greatest HIV prevalence was conducted between July 2014 and May 2015. Participants responded to a patient vignette of a PWID and asked to indicate whether the patient would be a candidate for PrEP and why via free-response text. Descriptive statistics are reported using frequency measures. Bivariate analyses were conducted using chi-squared comparisons and logistical regression. Results: Survey data from 480 providers were included in analyses. Of the 480 responses, 85.5% were classified as PrEP aware, while 14.2% were PrEP unaware. Additionally, 82.6% indicated the patient would be a good candidate for PrEP, 4.4% believed the patient was not a good candidate for PrEP, and 13% were unsure. Among those who were unsure or would not prescribe PrEP (n = 84), open-ended responses indicated lack of knowledge (42.9%), concern about adherence (27.4%), concern about cost (4.8%), and bias (7.1%) as the primary reasons. Conclusions: Although the majority of providers in this study did not demonstrate bias against PWID, our study found that limited PrEP knowledge and bias are barriers to PrEP prescription among PWID for some providers. Interventions are needed that increase PrEP awareness of CDC guidelines and reduce implicit bias among providers.

People living with HIV in rural parts of the Southern United States face poor outcomes along the HIV care continuum. Additionally, over half of people with diagnosed HIV are age 50 and older. Older adults living with HIV in the rural South often have complex health and social needs associated with HIV, aging, and the rural environment. Research is needed to understand what support organizations and clinics need in providing care to this population. This qualitative study examines the challenges health and social service providers face in caring for older patients living with HIV. In 2020–2021, we interviewed 27 key informants who work in organizations that provide care to older adults with HIV in the seven states with high rural HIV burden: Alabama, Arkansas, Kentucky, Mississippi, Missouri, Oklahoma, and South Carolina. Our findings highlight how racism and poverty; culture, politics, and religion; and a lack of healthcare infrastructure collectively shape access to HIV care for older adults in the South. Rural health and social service providers need structural-level changes to improve their care and services.

During corneal wound healing, corneal keratocytes are exposed to both biophysical and soluble cues that cause them to transform from a quiescent state to a repair phenotype. How keratocytes integrate these multiple cues simultaneously is not well understood. To investigate this process, primary rabbit corneal keratocytes were cultured on substrates patterned with aligned collagen fibrils and coated with adsorbed fibronectin. After 2 or 5 days of culture, keratocytes were fixed and stained to assess changes in cell morphology and markers of myofibroblastic activation by fluorescence microscopy. Initially, adsorbed fibronectin had an activating effect on the keratocytes as evidenced by changes in cell shape, stress fiber formation, and expression of alpha-smooth muscle actin (α-SMA). The magnitude of these effects depended upon substrate topography (i.e., flat substrate vs aligned collagen fibrils) and decreased with culture time. When keratocytes were simultaneously exposed to adsorbed fibronectin and soluble platelet-derived growth factor-BB (PDGF-BB), the cells elongated and had reduced expression of stress fibers and α-SMA. In the presence of PDGF-BB, keratocytes plated on the aligned collagen fibrils elongated in the direction of the fibrils. These results provide new information on how keratocytes respond to multiple simultaneous cues and how the anisotropic topography of aligned collagen fibrils influences keratocyte behavior.

Vimentin has been reported to play diverse roles in cell processes such as spreading, migration, cell–matrix adhesion, and fibrotic transformation. Here, we assess how vimentin impacts cell spreading, morphology, and myofibroblast transformation of human corneal fibroblasts. Overall, although knockout (KO) of vimentin did not dramatically impact corneal fibroblast spreading and mechanical activity (traction force), cell elongation in response to PDGF was reduced in vimentin KO cells as compared to controls. Blocking vimentin polymerization using Withaferin had even more pronounced effects on cell spreading and also inhibited cell-induced matrix contraction. Furthermore, although absence of vimentin did not completely block TGFβ-induced myofibroblast transformation, the degree of transformation and amount of αSMA protein expression was reduced. Proteomics showed that vimentin KO cells cultured in TGFβ had a similar pattern of protein expression as controls. One exception included periostin, an ECM protein associated with wound healing and fibrosis in other cell types, which was highly expressed only in Vim KO cells. We also demonstrate for the first time that LRRC15, a protein previously associated with myofibroblast transformation of cancer-associated fibroblasts, is also expressed by corneal myofibroblasts. Interestingly, proteins associated with LRRC15 in other cell types, such as collagen, fibronectin, β1 integrin and α11 integrin, were also upregulated. Overall, our data show that vimentin impacts both corneal fibroblast spreading and myofibroblast transformation. We also identified novel proteins that may regulate corneal myofibroblast transformation in the presence and/or absence of vimentin. [ABSTRACT FROM AUTHOR]

Background With the rising toll of the opioid crisis, oculoplastic surgeons have been looking at methods to decrease opioid prescription. Objectives The aim of this study was to identify factors that correlate with opioid usage after oculoplastic surgery. Methods This was a prospective study conducted at University of Texas Southwestern. All patients who underwent an oculoplastic procedure were eligible for inclusion. Patients enrolled were provided 20 tablets of tramadol 50 mg, to take 1 tablet every 6 hours as needed for pain. At their postoperative week 1 appointment, participants had the remaining number of unused opioid tablets counted. The number of tablets taken were calculated by subtracting the remaining number of tablets from the original prescribed amount. Results A total of 310 patients were enrolled in our study. Of these, 129 patients met the inclusion criteria. There was a statistically significant difference in the number of tramadol tablets taken between procedures for upper eyelids, lower eyelids, and both eyelids (P <.01). There were no statistically significant differences in tramadol usage when comparing procedures on eyelids with orbit procedures(P =.30), cosmetic with noncosmetic procedures (P =.52), males with females (P =.87), or patients naive to oculoplastic procedures with those undergoing reoperation (P =.58). Longer procedures were correlated with greater tramadol usage (R = 0.28, P <.01). Conclusions This is the first study in the literature that has objectively quantified opioid usage after oculoplastic surgery in a prospective manner. Procedures that involve both upper and lower eyelids simultaneously and longer procedures resulted in higher opioid use. Orbital procedures, cosmetic procedures, sex, and procedural naivety were not found to be associated with higher opioid usage. Level of Evidence: 4 [ABSTRACT FROM AUTHOR]

Following injury and refractive surgery, corneal wound healing can initiate a protracted fibrotic response that interferes with ocular function. This fibrosis is related, in part, to the myofibroblast differentiation of corneal keratocytes in response to transforming growth factor beta 1 (TGF-β1). Previous studies have shown that changes in the mechanical properties of the extracellular matrix (ECM) can regulate this process, but the mechanotransductive pathways that govern stiffness-dependent changes in keratocyte differentiation remain unclear. Here, we used a polyacrylamide (PA) gel system to investigate how mechanosensing via focal adhesions (FAs) regulates the stiffness-dependent myofibroblast differentiation of primary corneal keratocytes treated with TGF-β1. Soft (1 kPa) and stiff (10 kPa) PA substrata were fabricated on glass coverslips, plated with corneal keratocytes, and cultured in defined serum free media with or without exogenous TGF-β1. In some experiments, an inhibitor of focal adhesion kinase (FAK) activation was also added to the media. Cells were fixed and stained for F-actin, as well as markers for myofibroblast differentiation (α-SMA), actomyosin contractility phosphorylated myosin light chain (pMLC), focal adhesions (vinculin), or Smad activity (pSmad3). We also used traction force microscopy (TFM) to quantify cellular traction stresses. Treatment with TGF-β1 elicited stiffness-dependent differences in the number, size, and subcellular distribution of FAs, but not in the nuclear localization of pSmad3. On stiff substrata, cells exhibited large FAs distributed throughout the entire cell body, while on soft gels, the FAs were smaller, fewer in number, and localized primarily to the distal tips of thin cellular extensions. Larger and increased numbers of FAs correlated with elevated traction stresses, increased levels of α-SMA immunofluorescence, and more prominent and broadly distributed pMLC staining. Inhibition of FAK disrupted stiffness-dependent differences in keratocyte contractility, FA patterning, and myofibroblast differentiation in the presence of TGF-β1. Taken together, these data suggest that signaling downstream of FAs has important implications for the stiffness-dependent myofibroblast differentiation of corneal keratocytes.

Comprar, vender, interagir, integrar, enfim, relacionar-se. As empresas atuam em processo de ampla adaptação, uma vez que as diferentes formas de interação com seus clientes sofrem modificações sistemáticas em função da revolução que a tecnologia, em especial a internet, impõe ao mercado. Entender esta complexidade sobre o aspecto do varejo omnichannel é o principal objetivo deste trabalho. Com a utilização de estratégias metodológicas da bibliometria e revisão sistemática, este estudo apresenta um levantamento sobre o referido tema, considerando a lente do marketing como principal abordagem. A pesquisa foi realizada em sete bases de dados com intuito de elencar os principais artigos sobre o tema. Os termos pesquisados foram omnichannel e sua principal variação omni-channel. As bases utilizadas foram: Google Scholar, Webof Science, Scopus, Periódicos Capes, Scielo, Ebsco Host e Spell. Os principais resultados indicam que os pesquisadores de marketing tratam de omnichannel sob a perspectiva do consumidor (experiências de consumo e a importância da jornada do cliente no varejo omnichannel), das estratégias empresariais adotadas pelas empresas para atuar neste formato de varejo (investimentos em tecnologia para integrar a atuação em diferentes canais) e da interação do marketing com outras áreas organizacionais (integração da área de marketing com outras áreas para atuar neste contexto de varejo). Como conclusão sugere-se as seguintes pesquisas futuras: a) tópicos de entendimento da jornada do cliente; b) as etapas percorridas e, decifrar como as experiências do consumidor podem impactar em novas compras; c) entender como as empresas estão se preparando para lidar com este cenário omnichannel.

Dados de mercado revelam crescimento no acesso à internet e na conectividade de pessoas e empresas. Neste contexto, o marketing digital tem sido incorporado nas estratégias de diversas empresas. Em face da importância do tema, buscou-se, neste estudo, através de uma pesquisa bibliométrica seguida de uma revisão sistemática integrativa, mapear a compreensão da influência do marketing digital no comportamento de compra dos consumidores e propor uma agenda de pesquisa acerca do tema. Para isto, foram avaliados artigos publicados nas bases de dados: Ebsco, Periódicos Capes, Scopus, Spell e Web of Science entre os anos de 2000 a 2019. Os resultados apontaram que mais de 60% das publicações foram realizadas entre os anos de 2016 e 2019 e que temas emergentes como “IOT”, “economia compartilhada” e “marketing sensorial digital” são passiveis de melhor investigação. Estudos transculturais e longitudinais de temas como “influenciadores digitais” e “marketing boca a boca on-line” figuraram entre importantes gaps teóricos. Sugere-se estudos transculturais que permitam evidenciar características e gatilhos na utilização do marketing boca a boca digital, opção por modalidade de compra em grupo, opções por empresas com iniciativas sustentáveis e envolvendo a compra por impulso.

O estudo tem como objetivo analisar o efeito do humor no engajamento dos usuários em relação a publicações do perfil Globo Rural no Twitter. Trata-se de uma pesquisa quantitativa, conclusiva, descritiva, com coleta de dados por observação e análise via estatística descritiva e Teste-T. Foram coletadas e analisadas 1.100 publicações da revista Globo Rural no Twitter. Os resultados do estudo revelaram que há diferença estatística significativa e positiva nas três variáveis de engajamento em relação à presença de humor nas publicações analisadas. Observou-se também uma diferença nas médias de engajamento em relação ao dia e tipo de conteúdo da publicação: as médias nas publicações sem humor em finais de semana são maiores comparadas as publicações em dias úteis na semana, enquanto nas publicações com humor as médias em finais de semana são menores se comparadas as publicações em dias úteis na semana.

O objetivo deste trabalho é analisar como propagandas com humor incongruente veiculadas no Facebook atuam no engajamento, nas atitudes e na intenção de compra das consumidoras brasileiras. Um experimento realizado no Facebook, com 269 consumidoras brasileiras, permitiu testar se a presença de humor incongruente influencia a efetividade das propagandas, confirmando tal hipótese, além de demonstrar que se trata de um apelo humorístico com efeitos positivos sobre o público feminino. Entre as contribuições deste artigo, destaca-se que, seus achados confirmam que engajamento, atitudes e intenção de compra conformam importantes medidas da efetividade das propagandas no contexto virtual; revelam novas facetas sobre a percepção das mulheres quanto a estímulos tradicionalmente destinados aos homens; e apontam as redes sociais como elementos fundamentais à tomada de decisão do consumidor. Evidencia-se, assim, o papel da internet como plataforma de interação entre empresas e usuários e a necessidade de construção de um relacionamento nesta conjuntura, contexto em que o humor incongruente mostra-se capaz de chamar atenção, despertar engajamento, provocar atitudes favoráveis e, deste modo, conduzir a intenção de compra.

We have previously reported the flavonoid, quercetin, as a metabolic regulator and inhibitor of myofibroblast differentiation in vitro. Our current study evaluated the effects of topical application of quercetin on corneal scar development using two different animal models followed by RNA analysis in vitro. Wild-type C57BL/6J mice were anesthetized and the corneal epithelium and stroma were manually debrided, followed by quercetin (0.5, 1, 5, or 50 mM) or vehicle application. Corneal scarring was assessed for 3 weeks by slit lamp imaging and clinically scored. In a separate animal study, six New Zealand White rabbits underwent lamellar keratectomy surgery, followed by treatment with 5 mM quercetin or vehicle twice daily for three days. Stromal backscattering was assessed at week 3 by in vivo confocal microscopy. In mice, a single dose of 5 mM quercetin reduced corneal scar formation. In rabbits, stromal backscattering was substantially lower in two out of three animals in the quercetin-treated group. In vitro studies of human corneal fibroblasts showed that quercetin modulated select factors of the transforming growth factor-β (TGF-β) signaling pathway. These results provide evidence that quercetin may inhibit corneal scarring. Further studies in a larger cohort are required to validate the efficacy and safety of quercetin for clinical applications.