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1.
Cell ; 185(6): 995-1007.e18, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35303429

RESUMO

Several ebolaviruses cause outbreaks of severe disease. Vaccines and monoclonal antibody cocktails are available to treat Ebola virus (EBOV) infections, but not Sudan virus (SUDV) or other ebolaviruses. Current cocktails contain antibodies that cross-react with the secreted soluble glycoprotein (sGP) that absorbs virus-neutralizing antibodies. By sorting memory B cells from EBOV infection survivors, we isolated two broadly reactive anti-GP monoclonal antibodies, 1C3 and 1C11, that potently neutralize, protect rodents from disease, and lack sGP cross-reactivity. Both antibodies recognize quaternary epitopes in trimeric ebolavirus GP. 1C11 bridges adjacent protomers via the fusion loop. 1C3 has a tripartite epitope in the center of the trimer apex. One 1C3 antigen-binding fragment anchors simultaneously to the three receptor-binding sites in the GP trimer, and separate 1C3 paratope regions interact differently with identical residues on the three protomers. A cocktail of both antibodies completely protected nonhuman primates from EBOV and SUDV infections, indicating their potential clinical value.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Ebolavirus , Doença pelo Vírus Ebola , Animais , Epitopos , Glicoproteínas/química , Subunidades Proteicas
2.
BMC Plant Biol ; 24(1): 543, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872082

RESUMO

BACKGROUND: Bracts are important for ornamental plants, and their developmental regulation process is complex; however, relatively little research has been conducted on bracts. In this study, physiological, biochemical and morphological changes in Bougainvillea glabra leaves, leaf buds and bracts during seven developmental periods were systematically investigated. Moreover, transcriptomic data of B. glabra bracts were obtained using PacBio and Illumina sequencing technologies, and key genes regulating their development were screened. RESULTS: Scanning electron microscopy revealed that the bracts develop via a process involving regression of hairs and a color change from green to white. Transcriptome sequencing revealed 79,130,973 bp of transcript sequences and 45,788 transcripts. Differential gene expression analysis revealed 50 expression patterns across seven developmental periods, with significant variability in transcription factors such as BgAP1, BgFULL, BgCMB1, BgSPL16, BgSPL8, BgDEFA, BgEIL1, and BgBH305. KEGG and GO analyses of growth and development showed the involvement of chlorophyll metabolism and hormone-related metabolic pathways. The chlorophyll metabolism genes included BgPORA, BgSGR, BgPPH, BgPAO and BgRCCR. The growth hormone and abscisic acid signaling pathways involved 44 and 23 homologous genes, and coexpression network analyses revealed that the screened genes BgAPRR5 and BgEXLA1 are involved in the regulation of bract development. CONCLUSIONS: These findings improve the understanding of the molecular mechanism of plant bract development and provide important guidance for the molecular regulation and genetic improvement of the growth and development of ornamental plants, mainly ornamental bracts.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Nyctaginaceae , Nyctaginaceae/genética , Nyctaginaceae/metabolismo , Transcriptoma , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento
3.
J Virol ; 97(5): e0188822, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36975793

RESUMO

Zaïre ebolavirus (EBOV) causes Ebola virus disease (EVD), a devastating viral hemorrhagic fever in humans. Nonhuman primate (NHP) models of EVD traditionally use intramuscular infection with higher case fatality rates and reduced mean time-to-death compared to contact transmission typical of human cases of EVD. A cynomolgus macaque model of oral and conjunctival EBOV was used to further characterize the more clinically relevant contact transmission of EVD. NHPs challenged via the oral route had an overall 50% survival rate. NHPs challenged with a target dose of 1 × 102 PFU or 1 × 104 PFU of EBOV via the conjunctival route had 40% and 100% mortality, respectively. Classic signs of lethal EVD-like disease were observed in all NHPs that succumbed to EBOV infection including viremia, hematological abnormalities, clinical chemistries indicative of hepatic and renal disease, and histopathological findings. Evidence of EBOV viral persistence in the eye was observed in NHPs challenged via the conjunctival route. IMPORTANCE This study is the first to examine the Kikwit strain of EBOV, the most commonly used strain, in the gold-standard macaque model of infection. Additionally, this is the first description of the detection of virus in the vitreous fluid, an immune privileged site that has been proposed as a viral reservoir, following conjunctival challenge. The oral and conjunctival macaque challenge model of EVD described here more faithfully recapitulates the prodrome that has been reported for human EVD. This work paves the way for more advanced studies to model contact transmission of EVD, including early events in mucosal infection and immunity, as well as the establishment of persistent viral infection and the emergence from these reservoirs.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Humanos , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/transmissão , Macaca fascicularis , Modelos Animais de Doenças , Túnica Conjuntiva/virologia , Transmissão de Doença Infecciosa
4.
BMC Med Res Methodol ; 24(1): 189, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39210285

RESUMO

BACKGROUND: Accurate prediction of subject recruitment, which is critical to the success of a study, remains an ongoing challenge. Previous prediction models often rely on parametric assumptions which are not always met or may be difficult to implement. We aim to develop a novel method that is less sensitive to model assumptions and relatively easy to implement. METHODS: We create a weighted resampling-based approach to predict enrollment in year two based on recruitment data from year one of the completed GRIPS and PACE clinical trials. Different weight functions accounted for a range of potential enrollment trajectory patterns. Prediction accuracy was measured by Euclidean distance for enrollment sequence in year two, total enrollment over time, and total weeks to enroll a fixed number of subjects, against the actual year two enrollment data. We compare the performance of the proposed method with an existing Bayesian method. RESULTS: Weighted resampling using GRIPS data resulted in closer prediction evidenced by better coverage of observed enrollment with the prediction intervals and smaller Euclidean distance from actual enrollment in year 2, especially when enrollment gaps were filled prior to the weighted resampling. These scenarios also produced more accurate predictions for total enrollment and number of weeks to enroll 50 participants. These same scenarios outperformed an existing Bayesian method for all 3 accuracy measures. In PACE data, using a reduced year 1 enrollment resulted in closer prediction evidenced by better coverage of observed enrollment with the prediction intervals and smaller Euclidean distance from actual enrollment in year 2, with the weighted resampling scenarios better reflecting the seasonal variation seen in year (1) The reduced enrollment scenarios resulted in closer prediction for total enrollment over 6 and 12 months into year (2) These same scenarios also outperformed an existing Bayesian method for relevant accuracy measures. CONCLUSION: The results demonstrate the feasibility and flexibility for a resampling-based, non-parametric approach for prediction of clinical trial recruitment with limited early enrollment data. Application to a wider setting and long-term prediction accuracy require further investigation.


Assuntos
Teorema de Bayes , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Idoso , Pacientes Internados/estatística & dados numéricos , Estatísticas não Paramétricas , Feminino
5.
Macromol Rapid Commun ; 45(7): e2300647, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38243849

RESUMO

The rise in universal population and accompanying demands have directed toward an exponential surge in the generation of polymeric waste. The estimate predicts that world-wide plastic production will rise to ≈590 million metric tons by 2050, whereas 5000 million more tires will be routinely abandoned by 2030. Handling this waste and its detrimental consequences on the Earth's ecosystem and human health presents a significant challenge. Converting the wastes into carbon-based functional materials viz. activated carbon, graphene, and nanotubes is considered the most scientific and adaptable method. Herein, this world provides an overview of the various sources of polymeric wastes, modes of build-up, impact on the environment, and management approaches. Update on advances and novel modifications made in methodologies for converting diverse types of polymeric wastes into carbon nanomaterials over the last 5 years are given. A remarkable focus is made to comprehend the applications of polymeric waste-derived carbon nanomaterials (PWDCNMs) in the CO2 capture, removal of heavy metal ions, supercapacitor-based energy storage and water splitting with an emphasis on the correlation between PWDCNMs' properties and their performances. This review offers insights into emerging developments in the upcycling of polymeric wastes and their applications in environment and energy.


Assuntos
Metais Pesados , Nanoestruturas , Nanotubos , Humanos , Polímeros , Ecossistema
6.
Lipids Health Dis ; 23(1): 317, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334123

RESUMO

BACKGROUND: This paper investigated the link between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and diabetic kidney disease (DKD) in adult diabetic patients and identified the optimal NHHR value for impacting DKD. METHODS: This cross-sectional research made use of records from the National Health and Nutrition Examination Survey (NHANES) executed between 2005 and 2016. The link of NHHR to DKD risk was analyzed by logistic regression and restricted cubic spline (RCS) models. The stability and reliability of the results were assessed by subgroup analysis and sensitivity analysis. RESULTS: In total, 4,177 participants were involved. As a continuous variable, NHHR was markedly connected to an increased risk of DKD (OR 1.07, 95% CI 1.02, 1.12, P < 0.01). When NHHR was grouped in quartiles, relative to the reference set, the highest NHHR group was also linked to a heightened risk of DKD (OR 1.23, 95% CI 1.01, 1.50, P < 0.05). The outcome of RCS show a "J" shaped correlation between NHHR and DKD risk (P for nonlinear = 0.0136). The risk of developing DKD was the lowest when NHHR equals 2.66. Subgroup analysis revealed that the link of NHHR to DKD persisted in participants aged below 40, females, non-smokers, and those without hyperuricemia. Sensitivity analysis demonstrated a certain robustness in this association. CONCLUSION: A meaningful link is present between NHHR and DKD. An NHHR value of around 2.66 could represent the ideal cutoff for assessing DKD risk.


Assuntos
HDL-Colesterol , Nefropatias Diabéticas , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Nefropatias Diabéticas/sangue , HDL-Colesterol/sangue , Estados Unidos/epidemiologia , Adulto , Fatores de Risco , Inquéritos Nutricionais , Idoso , Colesterol/sangue , Modelos Logísticos , LDL-Colesterol/sangue
7.
Int J Behav Med ; 31(2): 192-201, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36952218

RESUMO

BACKGROUND: This study examined the trends in diabetes medication taking and its association with the incidence of depression in patients with type 2 diabetes (T2D). METHOD: A retrospective cohort of Medicare enrollees with regular care in 2010 was defined from 100% Texas Medicare claims. The impact of medication taking on incident depression was evaluated from 2010 to 2018. Cox proportional hazards regressions were used to estimate the association between medication taking and depression. RESULTS: A total of 72,461 patients with T2D and with regular care were analyzed. Among 60,216 treated patients, the regular medication taking rate slightly increased from 60.8 to 63.2% during the study period. Patients with regular medication taking at baseline had a 9% lower risk of developing depression (hazard ratio [HR]: 0.91, 95% confidence interval [CI]: 0.89-0.94), and the magnitude of the association increased after adjustment of the model for time-varied medication taking (HR: 0.82, 95% CI: 0.79-0.85). The presence of nephropathy had the greatest mediating effect (23.2%) on the association of medication taking and depression. CONCLUSION: We demonstrated a steady but modest increase in regular diabetes medication taking over a 9-year period and a significant relationship between medication taking and incident depression in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Idoso , Estados Unidos/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Retrospectivos , Depressão/epidemiologia , Depressão/complicações , Incidência , Medicare , Fatores de Risco
8.
BMC Plant Biol ; 23(1): 133, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36882694

RESUMO

BACKGROUND: Loropetalum chinense var. rubrum (L. chinense var. rubrum) is a precious, coloured-leaf native ornamental plant in the Hunan Province. We found an L. chinense var. rubrum tree with three different leaf colours: GL (green leaf), ML (mosaic leaf), and PL (purple leaf). The mechanism of leaf coloration in this plant is still unclear. Therefore, this study aimed to identify the metabolites and genes involved in determining the colour composition of L. chinense var. rubrum leaves, using phenotypic/anatomic observations, pigment content detection, and comparative metabolomics and transcriptomics. RESULTS: We observed that the mesophyll cells in PL were purple, while those in GL were green and those in ML were a mix of purple-green. The contents of chlorophyll a, b, carotenoids, and total chlorophyll in PL and ML were significantly lower than those in GL. While the anthocyanin content in PL and ML was significantly higher than that in GL. The metabolomics results showed the differences in the content of cyanidin 3-O-glucoside, delphinidin 3-O-glucoside, cyanidin 3,5-O-diglucoside, pelargonidin, and petunidin 3,5-diglucoside in ML, GL, and PL were significant. Considering that the change trend of anthocyanin content change was consistent with the leaf colour difference, we speculated that these compounds might influence the colour of L. chinense var. rubrum leaves. Using transcriptomics, we finally identified nine differentially expressed structural genes (one ANR (ANR1217); four CYP75As (CYP75A1815, CYP75A2846, CYP75A2909, and CYP75A1716); four UFGTs (UFGT1876, UFGT1649, UFGT1839, and UFGT3273) and nine transcription factors (two MYBs (MYB1057 and MYB1211), one MADS-box (MADS1235), two AP2-likes (AP2-like1779 and AP2-like2234), one bZIP (bZIP3720), two WD40s (WD2173 and WD1867) and one bHLH (bHLH1631) that might be related to flavonoid biosynthesis and then impacted the appearance of colour in L. chinense var. rubrum leaves. CONCLUSION: This study revealed potential molecular mechanisms associated with leaf coloration in L. chinense var. rubrum by analyzing differential metabolites and genes related to the anthocyanin biosynthesis pathway. It also provided a reference for research on leaf colour variation in other ornamental plants.


Assuntos
Antocianinas , Transcriptoma , Clorofila A , Metaboloma , Metabolômica
9.
Soc Psychiatry Psychiatr Epidemiol ; 58(2): 299-308, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36334100

RESUMO

PURPOSE: Despite substantially higher prevalence of depression among people living with HIV/AIDS (PLWHA), few data exist on the incidence and correlates of depression in this population. This study assessed the effect of HIV infection, age, and cohort period on the risk of developing depression by sex among older U.S. Medicare beneficiaries. METHODS: We constructed a retrospective matched cohort using a 5% nationally representative sample of Medicare beneficiaries (1996-2015). People with newly diagnosed (n = 1309) and previously diagnosed (n = 1057) HIV were individually matched with up to three beneficiaries without HIV (n = 6805). Fine-Gray models adjusted for baseline covariates were used to assess the effect of HIV status on developing depression by sex strata. RESULTS: PLWHA, especially females, had higher risk of developing depression within five years. The relative subdistribution hazards (sHR) for depression among three HIV exposure groups differed between males and females and indicated a marginally significant interaction (p = 0.08). The sHR (95% CI) for newly and previously diagnosed HIV (vs. people without HIV) were 1.6 (1.3, 1.9) and 1.9 (1.5, 2.4) for males, and 1.5 (1.2, 1.8) and 1.2 (0.9, 1.7) for females. The risk of depression increased with age [sHR 1.3 (1.1, 1.5), 80 + vs. 65-69] and cohort period [sHR 1.3 (1.1, 1.5), 2011-2015 vs. 1995-2000]. CONCLUSIONS: HIV infection increased the risk of developing depression within 5 years, especially among people with newly diagnosed HIV and females. This risk increased with older age and in recent HIV epidemic periods, suggesting a need for robust mental health treatment in HIV primary care.


Assuntos
Infecções por HIV , Idoso , Masculino , Feminino , Humanos , Estados Unidos/epidemiologia , Infecções por HIV/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Depressão/epidemiologia , Depressão/etiologia , Medicare
10.
Plant Dis ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923979

RESUMO

Ampelopsis grossedentata, commonly known as "Vine Tea" and well-recognized for its rich flavonoid content, is mainly distributed in the southern regions of the Yangtze River basin in China. These regions include Hunan, Hubei, Jiangxi, and Guizhou provinces. Vine Tea is mainly consumed as an herbal tea and has garnered attention for its reported health benefits, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and neuroprotective properties. It has been used to alleviate coughs and sore throats (Zhang et al., 2021; Wang et al., 2017; Gao et al., 2009). In the Zhangjiajie region of Hunan province alone, the Vine Tea planting area reached 7,670.5 hectares and produced commercial goods worth 1.417 billion RMB in 2022. In May 2021, leaf margins and veins fading to yellowing mottling, and crumpling of leaf blades in the shape of a boat symptoms were found in ~16% of Vine Tea plants in the Sanjiakuan Township, Yongding District, Zhangjiajie region (29°15'E, 110°30' N) (Figure 1a, b, c). (Figure 1a, b, c). Phytoplasma-like microbial cells (small oval shaped bacterial cells, around 1000 nm in size) were observed in sieve tube cells in the phloem of diseased leaves using transmission electron microscopy. No such cell was observed in the phloem of healthy leaves (Figure 2a, b). To investigate the potential association between phytoplasma and the observed symptoms of the diseased plants, total DNA was isolated from ten diseasedeaves and compared with ten healthy leaves from the same field using SteadyPure Plant Genomic DNA Extraction Kit. The isolated DNAs were analyzed first in a direct PCR using universal phytoplasma primer pair R16mF2/R16mR1 targeting the 16S rRNA gene (Gundersen and Lee 1996) and specific pair rpF1/rpR1 (Lee et al. 1998) targeting the DNA fragment encoding partial ribosomal proteins (rp) L22 (complete) and S3 and S19 (partial). The initial amplified products were used as templates and further amplified by nested PCR respectively with primer pair R16F2n/R16R2 for the 16S rRNA gene (Lee et al. 1998) and the rpF2/rpR2 primer pair for the rp gene (Martini et al. 2007). No amplification was obtained with DNA from healthy leaf samples using any of the four primer pairs. The amplified fragments from diseased leaves by nested PCR were cloned and sequenced (Qingke Biotech, China). The obtained sequences have been deposited in GenBank with accession numbers OR282806 for the 16S rRNA gene and GenBank OR353012 for the rp gene. BLASTn analysis revealed that the partial 16S rRNA gene sequence in our sample shared 99.4% nucleotide sequence identity with 'Candidatus Phytoplasma sp.' (MW364378) and 'Peony yellows phytoplasma' (KY814723) of the 16SrI group. Similarly, our rp gene sequence shared 99.6% nucleotide identity with the rpI group of phytoplasma such as the 'Balsamine virescence phytoplasma' (JN572890) and 'Paulownia witches'-broom phytoplasma' (HM146079). Phylogenetic analysis of the 16S rRNA and rp sequences using MEGA version 7.0 revealed that the phytoplasma strain associated with A. grossedentata yellow leaf syndrome in our study site belonged to the 16SrI (Candidatus Phytoplasma asteris) group of phytoplasma (Figure 3a, b). Using the interactive online phytoplasma classification tool iPhyClassifier (Zhao et al., 2009), virtual restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene sequences showed our strain having a distinct RFLP map but was closest to that of the onion yellow phytoplasma 16SrI-B subgroup (GenBank accession number: AP006628), with a similarity coefficient of 0.94 (Figure 4a, b). To confirm phytoplasma transmission, healthy plants were inoculated with three scions of infected plants of A. grossedentata. After 16 days, the new leaves of the inoculated A. grossedentata showed yellow leaf symptoms (Figure 5a, b, c), akin to the symptoms originally observed in the field, and the outer contour of the leaf margin appeared chlorotic. After 26 days, primer pairs R16mF2/R16R1 and R16F2n/R16R2 were used for nested PCR detection of phytoplasma in symptomatic A. grossedentata leaves. Phytoplasma was detected in the first and second leaves of symptomatic branches and leaves while negative control showed no amplification. Sequencing of the amplified fragments showed 100% nucleotide identity to the strain from the grafting source. Our results indicated that the pathogen and the disease can be transmitted by tissue grafting, consistent with the biological characteristics of phytoplasma, and further confirmed that the phytoplasma was the pathogen of yellow leaf syndrome of A. grossedentata. Toour knowledge, this is the first report of phytoplasma of group 16SrI affecting A. grossedentata.

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