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1.
Nat Immunol ; 25(3): 462-470, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38278966

RESUMEN

The persistence of CD4+ T cells carrying latent human immunodeficiency virus-1 (HIV-1) proviruses is the main barrier to a cure. New therapeutics to enhance HIV-1-specific immune responses and clear infected cells will probably be necessary to achieve reduction of the latent reservoir. In the present study, we report two single-chain diabodies (scDbs) that target the HIV-1 envelope protein (Env) and the human type III Fcγ receptor (CD16). We show that the scDbs promoted robust and HIV-1-specific natural killer (NK) cell activation and NK cell-mediated lysis of infected cells. Cocultures of CD4+ T cells from people with HIV-1 on antiretroviral therapy (ART) with autologous NK cells and the scDbs resulted in marked elimination of reservoir cells that was dependent on latency reversal. Treatment of human interleukin-15 transgenic NSG mice with one of the scDbs after ART initiation enhanced NK cell activity and reduced reservoir size. Thus, HIV-1-specific scDbs merit further evaluation as potential therapeutics for clearance of the latent reservoir.


Asunto(s)
Anticuerpos Biespecíficos , VIH-1 , Animales , Ratones , Humanos , Células Asesinas Naturales , Citotoxicidad Inmunológica , Muerte Celular , Ratones Transgénicos
2.
Cell ; 155(3): 540-51, 2013 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-24243014

RESUMEN

Antiretroviral therapy fails to cure HIV-1 infection because latent proviruses persist in resting CD4(+) T cells. T cell activation reverses latency, but <1% of proviruses are induced to release infectious virus after maximum in vitro activation. The noninduced proviruses are generally considered defective but have not been characterized. Analysis of 213 noninduced proviral clones from treated patients showed 88.3% with identifiable defects but 11.7% with intact genomes and normal long terminal repeat (LTR) function. Using direct sequencing and genome synthesis, we reconstructed full-length intact noninduced proviral clones and demonstrated growth kinetics comparable to reconstructed induced proviruses from the same patients. Noninduced proviruses have unmethylated promoters and are integrated into active transcription units. Thus, it cannot be excluded that they may become activated in vivo. The identification of replication-competent noninduced proviruses indicates that the size of the latent reservoir-and, hence, the barrier to cure-may be up to 60-fold greater than previously estimated.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/genética , Latencia del Virus , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Metilación de ADN , Duplicado del Terminal Largo de VIH , Activación de Linfocitos , Datos de Secuencia Molecular , Mutación , Filogenia , Provirus/genética , Alineación de Secuencia
3.
Plant J ; 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39401077

RESUMEN

Polyamines act as protective compounds directly protecting plants from stress-related damage, while also acting as signaling molecules to participate in serious abiotic stresses. However, the molecular mechanisms underlying these effects are poorly understood. Here, we utilized metabolome genome-wide association study to investigate the polyamine content of wild and cultivated tomato accessions, and we discovered a new gene cluster that drove polyamine content during tomato domestication. The gene cluster contains two polyphenol oxidases (SlPPOE and SlPPOF), two BAHD acyltransferases (SlAT4 and SlAT5), a coumaroyl-CoA ligase (Sl4CL6), and a polyamine uptake transporter (SlPUT3). SlPUT3 mediates polyamine uptake and transport, while the five other genes are involved in polyamine modification. Further salt tolerance assays demonstrated that SlPPOE, SlPPOF, and SlAT5 overexpression lines showed greater phenolamide accumulation and salt tolerance as compared with wild-type (WT). Meanwhile, the exogenous application of Spm to SlPUT3-OE lines displayed salt tolerance compared with WT, while having the opposite effect in slput3 lines, confirms that the polyamine and phenolamide can play a protective role by alleviating cell damage. SlPUT3 interacted with SlPIP2;4, a H2O2 transport protein, to maintain H2O2 homeostasis. Polyamine-derived H2O2 linked Spm to stress responses, suggesting that Spm signaling activates stress response pathways. Collectively, our finding reveals that the H2O2-polyamine-phenolamide module coordinately enhanced tomato salt stress tolerance and provide a foundation for tomato stress-resistance breeding.

4.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35110411

RESUMEN

In persons living with HIV-1 (PLWH) who start antiretroviral therapy (ART), plasma virus decays in a biphasic fashion to below the detection limit. The first phase reflects the short half-life (<1 d) of cells that produce most of the plasma virus. The second phase represents the slower turnover (t1/2 = 14 d) of another infected cell population, whose identity is unclear. Using the intact proviral DNA assay (IPDA) to distinguish intact and defective proviruses, we analyzed viral decay in 17 PLWH initiating ART. Circulating CD4+ T cells with intact proviruses include few of the rapidly decaying first-phase cells. Instead, this population initially decays more slowly (t1/2 = 12.9 d) in a process that largely represents death or exit from the circulation rather than transition to latency. This more protracted decay potentially allows for immune selection. After ∼3 mo, the decay slope changes, and CD4+ T cells with intact proviruses decay with a half-life of 19 mo, which is still shorter than that of the latently infected cells that persist on long-term ART. Two-long-terminal repeat (2LTR) circles decay with fast and slow phases paralleling intact proviruses, a finding that precludes their use as a simple marker of ongoing viral replication. Proviruses with defects at the 5' or 3' end of the genome show equivalent monophasic decay at rates that vary among individuals. Understanding these complex early decay processes is important for correct use of reservoir assays and may provide insights into properties of surviving cells that can constitute the stable latent reservoir.


Asunto(s)
Antirretrovirales/farmacología , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Provirus/efectos de los fármacos , Virión/efectos de los fármacos , Linfocitos T CD4-Positivos/efectos de los fármacos , Células Cultivadas , ADN Viral/efectos de los fármacos , Humanos , Estudios Longitudinales , Carga Viral/efectos de los fármacos , Latencia del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos
5.
PLoS Pathog ; 18(9): e1010845, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36074794

RESUMEN

Antiretroviral therapy (ART) effectively inhibits HIV-1 replication but is not curative due to the persistence of a latent viral reservoir in resting CD4+ T cells. This reservoir is a major barrier to cure. Sequencing studies have revealed that the population of proviruses persisting in ART-treated individuals is dominated by defective proviruses that cannot give rise to viral rebound due to fatal defects including large deletions and APOBEC3-mediated hypermutation. Near full genome sequencing (nFGS) of individual proviruses is used in reservoir assays to provide an estimate of the fraction of proviruses that are intact. nFGS methods rely on a long-distance outer PCR capturing most (~9 kb) of the genome, followed by nested inner PCRs. The outer PCR is carried out at limit dilution, and interpretation of the results is based on the assumption that all proviruses are quantitatively captured. Here, we evaluate nFGS methods using the intact proviral DNA assay (IPDA), a multiplex digital droplet PCR assay that quantitates intact and defective proviruses with single molecule sensitivity using only short, highly efficient amplicons. We analyzed proviral templates of known sequence to avoid the additional complication of sequence polymorphism. With the IPDA, we quantitated molecular yields at each step of nFGS methods. We demonstrate that nFGS methods are inefficient and miss ~70% of full-length proviruses due to amplification failure at the initial outer PCR step. In contrast, proviruses with large internal deletions encompassing 70% of the genome can be quantitatively amplified under the same conditions. Accurate measurement of the latent reservoir of HIV-1 is essential for evaluating the efficacy of cure strategies, and the bias against full length proviruses in nFGS methods must be considered.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Linfocitos T CD4-Positivos , ADN Viral/genética , VIH-1/genética , Humanos , Provirus/genética , Carga Viral
6.
New Phytol ; 244(2): 694-707, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39166427

RESUMEN

Horizontal gene transfer (HGT) is a major driving force in the evolution of prokaryotic and eukaryotic genomes. Despite recent advances in distribution and ecological importance, the extensive pattern, especially in seed plants, and post-transfer adaptation of HGT-acquired genes in land plants remain elusive. We systematically identified 1150 foreign genes in 522 land plant genomes that were likely acquired via at least 322 distinct transfers from nonplant donors and confirmed that recent HGT events were unevenly distributed between seedless and seed plants. HGT-acquired genes evolved to be more similar to native genes in terms of average intron length due to intron gains, and HGT-acquired genes containing introns exhibited higher expression levels than those lacking introns, suggesting that intron gains may be involved in the post-transfer adaptation of HGT in land plants. Functional validation of bacteria-derived gene GuaD in mosses and gymnosperms revealed that the invasion of foreign genes introduced a novel bypass of guanine degradation and resulted in the loss of native pathway genes in some gymnosperms, eventually shaping three major types of guanine metabolism in land plants. We conclude that HGT has played a critical role in land plant evolution.


Asunto(s)
Embryophyta , Transferencia de Gen Horizontal , Genes de Plantas , Guanina , Intrones , Embryophyta/genética , Intrones/genética , Guanina/metabolismo , Filogenia , Adaptación Fisiológica/genética , Genoma de Planta , Evolución Molecular
7.
Opt Lett ; 49(7): 1852-1855, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560881

RESUMEN

We propose and demonstrate a short and broadband silicon mode-conversion polarization splitter-rotator (PSR) consisting of a mode-conversion taper and an adiabatic coupler-based mode sorter both optimized by adiabaticity engineering (AE). AE is used to optimize the distribution of adiabaticity parameter over the length of the PSR, providing shortcut to adiabaticity at a shorter device length. The total length of the PSR is 85 µm. The design is compatible with standard silicon photonics platforms and requires only one patterning step. Fabricated PSR has a polarization cross talk of less than -20 dB over the entire O-band for the TE polarization and a polarization cross talk of less than -15 dB from 1267 to 1348 nm for the TM polarization. Overall, the PSR shows low polarization cross talk (-15 dB) over a bandwidth of 81 nm in the O-band. Cross-wafer measurements show that the PSR has good fabrication tolerance.

8.
Oncology ; : 1-15, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39047691

RESUMEN

INTRODUCTION: As the primary members of the deubiquitinase family, ubiquitin-specific proteases can regulate the efficacy of immunotherapy and mediate immune evasion. However, further research is needed to explore the influence of USP52 on the prognosis of colorectal cancer (CRC), the tumor immune microenvironment, and therapeutic response. METHODS: The differential expression of USP52 between CRC and normal tissues was analyzed using multiple public databases. The relationship between USP52 with the prognosis and clinicopathological characteristics of CRC patients was evaluated, and a nomogram was constructed to predict patient survival based on USP52 expression. Subsequently, gene set variation analysis (GSVA) was used to explore the potential biological functions of USP52 in CRC. The impact of USP52 on the tumor microenvironment (TME) was estimated. Moreover, the effect of USP52 on the response to immunotherapy and chemotherapeutic drugs in CRC was investigated. Finally, the correlation between tumor mutation burden (TMB)/microsatellite instability (MSI) status and USP52 was explored. RESULTS: The expression of USP52 was markedly upregulated in CRC, correlating with a poor prognosis in patients. GSVA uncovered a strong association between high USP52 and immune suppression. Furthermore, high USP52 was found to be correlated with a non-inflamed TME, resulting in reduced immune cell infiltration levels. Additionally, it was observed that patients with high USP52 exhibited low sensitivity to both immunotherapy and chemotherapeutic drugs. Lastly, high USP52 was negatively associated with high TMB and MSI. CONCLUSION: This study revealed the significance of USP52 in TME, efficacy of therapy, and clinical prognosis in CRC, offering novel insights for the therapeutic advancements in CRC.

9.
Nutr J ; 23(1): 57, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38835080

RESUMEN

BACKGROUND: It is unclear if improving diet quality after midlife could reduce the risk of physical frailty at late life. We aimed to associate changes in diet quality after midlife with physical frailty at late life. METHODS: Diet quality in 12,580 participants from the Singapore Chinese Health Study was assessed with the Dietary Approaches to Stop Hypertension (DASH) scores at baseline (1993-1998; mean age 53 years) and follow-up 3 (2014-2016; mean age 73 years). Physical frailty was assessed using the modified Cardiovascular Health Study phenotype at follow-up 3. Multivariable logistic regressions examined associations between DASH scores and physical frailty. RESULTS: Comparing participants in extreme quartiles of DASH scores, the odds ratios (OR) [95% confidence interval (CI)] for physical frailty were 0.85 (0.73,0.99) at baseline and 0.49 (0.41, 0.58) at follow-up 3. Compared to participants with consistently low DASH scores, participants with consistently high scores (OR 0.74, 95% CI: 0.59, 0.94) and those with > 10% increase in scores (OR 0.78, 95% CI: 0.64, 0.95) had lower odds of frailty. Compared to those in the lowest DASH tertiles at both time-points, significantly lower odds of physical frailty were observed in those who were in the highest DASH tertiles at both time points [0.59 (0.48, 0.73)], and in those who improved their scores from the lowest [0.68 (0.51, 0.91)] or second tertile at baseline [0.61 (0.48, 0.76)] to the highest tertile at follow-up 3. CONCLUSIONS: Maintaining a high diet quality or a substantial improvement in diet quality after midlife could lower the risk of physical frailty at late life.


Asunto(s)
Dieta , Fragilidad , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Singapur , Dieta/métodos , Dieta/estadística & datos numéricos , Estudios de Cohortes , Enfoques Dietéticos para Detener la Hipertensión/métodos , Enfoques Dietéticos para Detener la Hipertensión/estadística & datos numéricos , Anciano Frágil/estadística & datos numéricos , Pueblo Asiatico , China
10.
Nutr J ; 23(1): 110, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304916

RESUMEN

BACKGROUND: Maternal feeding practices play a major role in children's dietary intakes. However, there is limited data on the associations between trajectories of dietary patterns (DPs) and patterns of maternal feeding practices during early childhood. METHODS: Using data from a multi-ethnic Asian cohort study, namely the Growing Up in Singapore Towards healthy Outcomes (GUSTO), dietary intakes were measured using Food Frequency Questionnaires in children at 18 months, 5 and 7 years of age. Maternal feeding practices were assessed using validated questionnaires at 15 months, 3 and 5 years of age. Principal component analysis was used to derive 2 major DPs at all time-points as well as patterns of maternal feeding practices. Group-based trajectory modelling was used to identify trajectory groups for the derived DPs. Multivariable logistic regression examined associations between patterns of maternal feeding practices and DP trajectory groups. RESULTS: Two DPs, namely the 'healthy' and 'less healthy' were consistently derived at 18 months, 5 and 7 years of age. From each DP, 2 stable DP trajectory groups were further identified between 18 months and 7 years of age. For the 'healthy' DP trajectory, majority of the children (Group 1) formed a consistent average adherence trajectory group (91.8%) while the remaining children (Group 2) showed a higher but decreasing adherence (8.2%) to this DP. For the 'less healthy' DP trajectory, most children (Group 1) formed a consistent average adherence trajectory (95.5%), while the remainder (Group 2) showed consistent higher adherence to this 'less healthy' DP (4.5%). Two patterns of maternal feeding practices were derived and labelled as 'structured with autonomy support' and 'coercive control', respectively, at ages 15 months, 3 and 5 years. Children whose mothers showed high adherence to the structured with autonomy support feeding practices at age 5 years were significantly more likely to be associated with the higher but decreasing 'healthy' DP trajectory group [OR = 3.62 (95% CI: 1.64, 7.99)]. CONCLUSIONS: A small number of children in this multi-ethnic study showed high adherence to the 'healthy' or 'less healthy' DP trajectory groups, respectively, while the majority showed average adherence to either of these trajectories. The positive association between structured with autonomy support maternal feeding practices and higher z-scores for the healthy DP trajectory highlights the importance of guiding parents on appropriate feeding practices.


Asunto(s)
Dieta , Conducta Alimentaria , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Pueblo Asiatico/estadística & datos numéricos , Estudios de Cohortes , Dieta/estadística & datos numéricos , Dieta/métodos , Etnicidad/estadística & datos numéricos , Madres/estadística & datos numéricos , Singapur , Encuestas y Cuestionarios
11.
Appetite ; 198: 107336, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38574819

RESUMEN

Studies examining preconception eating behaviours with longitudinal dietary patterns from preconception to late pregnancy as well as gestational weight gain (GWG) are limited. We derived dietary pattern trajectories from preconception to late-pregnancy, and related preconception eating behaviours to these trajectories and GWG. Preconception eating behaviours were assessed using the Three-Factor Eating Questionnaire measuring cognitive restraint (CR) - conscious restriction of food intake, emotional eating (EE) - overeating in response to negative emotions, and uncontrolled eating (UE) - overeating with a feeling of lack of control. Dietary intakes were measured at preconception, 20-21 and 34-36 weeks' gestation with food frequency questionnaires. Dietary patterns were determined using factor analysis, and trajectories derived using group-based trajectory modelling. Inadequate and excessive GWG were defined according to Institute of Medicine guidelines based on weights at preconception and the last antenatal visit (median: 38 weeks' gestation). Two dietary patterns were derived: 'Fast Food, Fried Snacks and Desserts (FFD)' and 'Soup, Fish and Vegetables (SFV)'. Adherence trajectories from preconception to late-pregnancy were characterised as consistently high ("stable-high") and low ("stable-low"). Women with higher UE scores had higher odds of being in the "stable-high" trajectory (n = 34) of the FFD pattern [Odds Ratio (OR): 1.25, 95% Confidence Interval (CI): 1.03, 1.51], compared to "stable-low" (n = 260). Percentages of women with inadequate, adequate or excessive GWG were 21.7% (n = 70), 25.8% (n = 83), and 52.5% (n = 169), respectively; women with higher EE scores had a higher likelihood of excessive GWG [Relative Risk Ratio (RRR): 1.35, 95% CI: 1.02, 1.80], but this association was attenuated after adjusting for preconception body mass index. Eating behaviour interventions to improve dietary patterns among pregnant women may need to start as early as preconception, incorporating strategies to manage UE.


Asunto(s)
Dieta , Conducta Alimentaria , Ganancia de Peso Gestacional , Adulto , Femenino , Humanos , Embarazo , Adulto Joven , Índice de Masa Corporal , Dieta/psicología , Conducta Alimentaria/psicología , Hiperfagia/psicología , Estudios Longitudinales , Encuestas y Cuestionarios
12.
Gen Physiol Biophys ; 43(3): 209-219, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38774921

RESUMEN

Atrial fibrillation (AF) is the most common cardiac arrhythmia and can cause serious complications. Several studies have shown that neutrophils may influence AF progression. However, the key genes related to neutrophils in AF have not been fully elucidated. Here, we downloaded microarray expression data of AF, and screened differentially expressed genes. Key immune cells in AF were identified by immune cell infiltration analysis. Weighted gene co-expression network analysis (WGCNA) and protein-protein interaction (PPI) analysis were used to construct gene co-expression modules and identify hub genes. The association between key genes and neutrophils was then verified. Our results showed that 303 differentially expressed genes (DEGs) were screened in AF and sinus rhythm (SR), of which 194 were up-regulated and 109 were down-regulated. DEGs were mainly enriched in functions and pathways of neutrophil activation and biological functions of neutrophil activation-mediated immune response. Immune infiltration analysis revealed elevated levels of neutrophil infiltration in AF. WGCNA analysis revealed that the modules in dark red were associated with neutrophils. PPI analysis of these modules yielded 10 hub genes. S100A12, FCGR3B and S100A8 are 3 potential key genes related to neutrophils in AF, which are significantly positively correlated with neutrophils. These genes deserve further investigation and may be potential therapeutic targets for AF.


Asunto(s)
Fibrilación Atrial , Neutrófilos , Fibrilación Atrial/genética , Fibrilación Atrial/inmunología , Neutrófilos/metabolismo , Neutrófilos/inmunología , Humanos , Mapas de Interacción de Proteínas/genética , Redes Reguladoras de Genes , Perfilación de la Expresión Génica
13.
New Phytol ; 239(4): 1353-1367, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37287391

RESUMEN

Steroidal glycoalkaloids (SGAs) constitute a characteristic class of antinutritional metabolites that are found in certain Solanum species. Despite the considerable studies on SGA biosynthesis, the mechanisms of crosstalk between hormone signaling pathways that regulate SGA content still remain to be elucidated. Here, we performed a metabolic genome-wide association study (mGWAS) based on the levels of SGA metabolites and identified SlERF.H6 as a negative regulator of bitter-SGA biosynthesis. SlERF.H6 repressed the expression of SGA biosynthetic glycoalkaloid metabolism (GAME) genes and caused a subsequent decrease in the abundance of bitter SGAs. Furthermore, SlERF.H6 were shown to act downstream of GAME9, a regulator of SGA biosynthesis in tomato. We also uncovered the interplay between ethylene and gibberellin (GA) signaling in regulating SGA biosynthesis. SlERF.H6, acting as a downstream component in ethylene signaling, modulated GA content by inhibiting SlGA2ox12 expression. Increasing levels of endogenous GA12 and GA53 in SlERF.H6-OE could inhibit of GA on SGA biosynthesis. Additionally, 1-aminocyclopropane-1-carboxylic acid (ACC) treatment decreased the stability of SlERF.H6, weakening its inhibition on GAME genes and SlGA2ox12, and caused bitter-SGA accumulation. Our findings reveal a key role of SlERF.H6 in the regulation of SGA biosynthesis through the coordinated ethylene-gibberellin signaling.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Giberelinas , Estudio de Asociación del Genoma Completo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas
14.
Artículo en Inglés | MEDLINE | ID: mdl-37022760

RESUMEN

A taxonomic study was carried out on strain BGMRC 0090T, which was isolated from seawater. The isolate was a Gram-negative, aerobic, flagellated, rod-shaped bacterium with algicidal activity. Optimal growth was observed at 30 °C, pH 6.0 and with 2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BGMRC 0090T belonged to the genus Parvularcula, with highest sequence similarity to Parvularcula lutaonensis CC-MMS-1T (98.4 %). Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values between strain BGMRC 0090T and five strains of the genus Parvularcula with publicly available genomes were below 84.0, 69.2 and 21.4 %, respectively. The genome of strain BGMRC 0090T was 3.2 Mb with 64.8 mol% DNA G+C content and encoded 2905 predicted proteins, three rRNA, 42 tRNA and four ncRNA genes. Some algicidal biosynthesis-associated genes were detected in the genome. Strain BGMRC 0090T contained Q-10 as the major quinone. The predominant fatty acids were identified as summed feature 8 (C18 : 1ω7c/ω6c) and C16 : 0. Based on the polyphasic evidence presented in this paper, strain BGMRC 0090T is concluded to represent a novel species of the genus Parvularcula, for which the name Parvularcula maris sp. nov. is proposed. The type strain is BGMRC 0090T (= KCTC 92591T=MCCC 1K08100T).


Asunto(s)
Ácidos Grasos , Fosfolípidos , Ácidos Grasos/química , Filogenia , Fosfolípidos/química , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana , Agua de Mar/microbiología
15.
Inorg Chem ; 62(46): 19006-19014, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37930938

RESUMEN

The application of X-ray imaging in military, industrial flaw detection, and medical examination is inseparable from the wide application of scintillator materials. In order to substitute for lead, lower costs, and reduce self-absorption, organic-inorganic hybrid lead-free perovskite scintillators are emerging as a new option. In this work, novel (TEA)2Zr1-xTexCl6 perovskite microcrystals (MCs) were successfully synthesized by a hydrothermal method, with Te4+ doping, which leads to yellow triplet-state self-trapped excitons emission. The emission peak of (TEA)2Zr1-xTexCl6 located at 605 nm under X-ray excitation, which was applied to X-ray imaging, shows a clear wiring structure inside the USB connector. The detection limit (DL) of 820 nGyair/s for (TEA)2Zr0.9Te0.1Cl6 is well below the dose rate corresponding to a standard medical X-ray diagnosis is 5.5 µGyair/s. This work opens up a new path for organic-inorganic hybrid lead-free scintillators.

16.
Ann Intern Med ; 175(1): 95-100, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34781719

RESUMEN

BACKGROUND: A sterilizing cure of HIV-1 infection has been reported in 2 persons living with HIV-1 who underwent allogeneic hematopoietic stem cell transplantations from donors who were homozygous for the CCR5Δ32 gene polymorphism. However, this has been considered elusive during natural infection. OBJECTIVE: To evaluate persistent HIV-1 reservoir cells in an elite controller with undetectable HIV-1 viremia for more than 8 years in the absence of antiretroviral therapy. DESIGN: Detailed investigation of virologic and immunologic characteristics. SETTING: Tertiary care centers in Buenos Aires, Argentina, and Boston, Massachusetts. PATIENT: A patient with HIV-1 infection and durable drug-free suppression of HIV-1 replication. MEASUREMENTS: Analysis of genome-intact and replication-competent HIV-1 using near-full-length individual proviral sequencing and viral outgrowth assays, respectively; analysis of HIV-1 plasma RNA by ultrasensitive HIV-1 viral load testing. RESULTS: No genome-intact HIV-1 proviruses were detected in analysis of a total of 1.188 billion peripheral blood mononuclear cells and 503 million mononuclear cells from placental tissues. Seven defective proviruses, some of them derived from clonally expanded cells, were detected. A viral outgrowth assay failed to retrieve replication-competent HIV-1 from 150 million resting CD4+ T cells. No HIV-1 RNA was detected in 4.5 mL of plasma. LIMITATIONS: Absence of evidence for intact HIV-1 proviruses in large numbers of cells is not evidence of absence of intact HIV-1 proviruses. A sterilizing cure of HIV-1 can never be empirically proved. CONCLUSION: Genome-intact and replication-competent HIV-1 were not detected in an elite controller despite analysis of massive numbers of cells from blood and tissues, suggesting that this patient may have naturally achieved a sterilizing cure of HIV-1 infection. These observations raise the possibility that a sterilizing cure may be an extremely rare but possible outcome of HIV-1 infection. PRIMARY FUNDING SOURCE: National Institutes of Health and Bill & Melinda Gates Foundation.


Asunto(s)
Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/genética , Receptores CCR5/genética , Adulto , Argentina , Linfocitos T CD4-Positivos/inmunología , Femenino , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno , Humanos , Massachusetts , Embarazo , Resultado del Embarazo , Provirus/genética , Provirus/inmunología , Carga Viral , Viremia/virología , Replicación Viral/inmunología
17.
Proc Natl Acad Sci U S A ; 117(27): 15763-15771, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32571938

RESUMEN

HIV-1 latency is a major barrier to cure. Identification of small molecules that destabilize latency and allow immune clearance of infected cells could lead to treatment-free remission. In vitro models of HIV-1 latency involving cell lines or primary cells have been developed for characterization of HIV-1 latency and high-throughput screening for latency-reversing agents (LRAs). We have shown that the majority of LRAs identified to date are relatively ineffective in cells from infected individuals despite activity in model systems. We show here that, for diverse LRAs, latency reversal observed in model systems involves a heat shock factor 1 (HSF1)-mediated stress pathway. Small-molecule inhibition of HSF1 attenuated HIV-1 latency reversal by histone deactylase inhibitors, protein kinase C agonists, and proteasome inhibitors without interfering with the known mechanism of action of these LRAs. However, latency reversal by second mitochondria-derived activator of caspase (SMAC) mimetics was not affected by inhibition of HSF1. In cells from infected individuals, inhibition of HSF1 attenuated latency reversal by phorbol ester+ionomycin but not by anti-CD3+anti-CD28. HSF1 promotes elongation of HIV-1 RNA by recruiting P-TEFb to the HIV-1 long terminal repeat (LTR), and we show that inhibition of HSF1 attenuates the formation of elongated HIV-1 transcripts. We demonstrate that in vitro models of latency have higher levels of the P-TEFb subunit cyclin T1 than primary cells, which may explain why many LRAs are functional in model systems but relatively ineffective in primary cells. Together, these studies provide insights into why particular LRA combinations are effective in reversing latency in cells from infected individuals.


Asunto(s)
Infecciones por VIH/genética , VIH-1/genética , Factores de Transcripción del Choque Térmico/genética , Latencia del Virus/genética , Fármacos Anti-VIH/farmacología , Proteínas Reguladoras de la Apoptosis/genética , Ciclina T/genética , Infecciones por VIH/virología , VIH-1/patogenicidad , Factores de Transcripción del Choque Térmico/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Proteínas Mitocondriales/genética , Factor B de Elongación Transcripcional Positiva/genética , Proteína Quinasa C/genética , ARN Viral/efectos de los fármacos , ARN Viral/genética , Bibliotecas de Moléculas Pequeñas/farmacología , Secuencias Repetidas Terminales/genética , Activación Viral/genética
18.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36834772

RESUMEN

Steroidal alkaloids (SAs) and steroidal glycoalkaloids (SGAs) are common constituents of plant species belonging to the Solanaceae family. However, the molecular mechanism regulating the formation of SAs and SGAs remains unknown. Here, genome-wide association mapping was used to elucidate SA and SGA regulation in tomatoes: a SlGAME5-like glycosyltransferase (Solyc10g085240) and the transcription factor SlDOG1 (Solyc10g085210) were significantly associated with steroidal alkaloid composition. In this study, it was found that rSlGAME5-like can catalyze a variety of substrates for glycosidation and can catalyze SA and flavonol pathways to form O-glucoside and O-galactoside in vitro. The overexpression of SlGAME5-like promoted α-tomatine, hydroxytomatine, and flavonol glycoside accumulation in tomatoes. Furthermore, assessments of natural variation combined with functional analyses identified SlDOG1 as a major determinant of tomato SGA content, which also promoted SA and SGA accumulation via the regulation of GAME gene expression. This study provides new insights into the regulatory mechanisms underlying SGA production in tomatoes.


Asunto(s)
Alcaloides , Solanaceae , Solanum lycopersicum , Estudio de Asociación del Genoma Completo , Alcaloides/química , Solanaceae/genética , Glicósidos/química
19.
Molecules ; 28(9)2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37175126

RESUMEN

Bone and cartilage disorders are the leading causes of musculoskeletal disability. There is no absolute cure for all bone and cartilage disorders. The exploration of natural compounds for the potential therapeutic use against bone and cartilage disorders is proving promising. Among these natural chemicals, naringin, a flavanone glycoside, is a potential candidate due to its multifaceted pharmacological activities in bone and cartilage tissues. Emerging studies indicate that naringin may promote osteogenic differentiation, inhibit osteoclast formation, and exhibit protective effects against osteoporosis in vivo and in vitro. Many signaling pathways, such as BMP-2, Wnt/ß-catenin, and VEGF/VEGFR, participate in the biological actions of naringin in mediating the pathological development of osteoporosis. In addition, the anti-inflammatory, anti-oxidative stress, and anti-apoptosis abilities of naringin also demonstrate its beneficial effects against bone and cartilage disorders, including intervertebral disc degeneration, osteoarthritis, rheumatoid arthritis, bone and cartilage tumors, and tibial dyschondroplasia. Naringin exhibits protective effects against bone and cartilage disorders. However, more efforts are still needed due to, at least in part, the uncertainty of drug targets. Further biological and pharmacological evaluations of naringin and its applications in bone tissue engineering, particularly its therapeutic effects against osteoporosis, might result in developing potential drug candidates.


Asunto(s)
Flavanonas , Osteoporosis , Humanos , Osteogénesis , Huesos , Flavanonas/farmacología , Flavanonas/uso terapéutico , Flavanonas/química , Osteoporosis/tratamiento farmacológico , Osteoporosis/etiología
20.
Br J Nutr ; 128(8): 1626-1637, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34776027

RESUMEN

Advances in technology enabled the development of a web-based, pictorial FFQ to collect parent-report dietary intakes of 7-year-old children in the Growing Up in Singapore Towards healthy Outcomes study. This study aimed to compare intakes estimated from a paper-FFQ and a web-FFQ and examine the relative validity of both FFQ against 3-d diet records (3DDR). Ninety-two mothers reported food intakes of their 7-year-old child on a paper-FFQ, a web-FFQ and a 3DDR. A usability questionnaire collected participants' feedback on the web-FFQ. Correlations and agreement in energy, nutrients and food groups intakes between the dietary assessments were evaluated using Pearson's correlation, Lin's concordance, Bland-Altman plots, Cohen's κ and tertile classification. The paper- and web-FFQ had good correlations (≥ 0·50) and acceptable-good agreement (Lin's concordance ≥ 0·30; Cohen's κ ≥ 0·41; ≥ 50 % correct and ≤ 10 % misclassification into same or extreme tertiles). Compared with 3DDR, both FFQ showed poor agreement (< 0·30) in assessing absolute intakes except micronutrients (web-FFQ had acceptable-good agreement), but showed acceptable-good ability to classify children into tertiles (κ ≥ 0·21; ≥ 40 % and ≤ 15 % correct or misclassification). Bland-Altman plots suggest good agreement between web-FFQ and 3DDR in assessing micronutrients and several food groups. The web-FFQ was well-received, and majority (81 %) preferred the web-FFQ over the paper-FFQ. The newly developed web-FFQ produced intake estimates comparable to the paper-FFQ, has acceptable-good agreement with 3DDR in assessing absolute micronutrients intakes and has acceptable-good ability to classify children according to categories of intakes. The positive acceptance of the web-FFQ makes it a feasible tool for future dietary data collection.


Asunto(s)
Dieta , Micronutrientes , Femenino , Humanos , Niño , Singapur , Encuestas y Cuestionarios , Registros de Dieta , Reproducibilidad de los Resultados , Encuestas sobre Dietas , Internet , Ingestión de Energía
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