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1.
Brief Bioinform ; 23(6)2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36326078

RESUMEN

Most polygenic risk score (PRS)models have been based on data from populations of European origins (accounting for the majority of the large genomics datasets, e.g. >78% in the UK Biobank and >85% in the GTEx project). Although several large-scale Asian biobanks were initiated (e.g. Japanese, Korean, Han Chinese biobanks), most other Asian countries have little or near-zero genomics data. To implement PRS models for under-represented populations, we explored transfer learning approaches, assuming that information from existing large datasets can compensate for the small sample size that can be feasibly obtained in developing countries, like Vietnam. Here, we benchmark 13 common PRS methods in meta-population strategy (combining individual genotype data from multiple populations) and multi-population strategy (combining summary statistics from multiple populations). Our results highlight the complementarity of different populations and the choice of methods should depend on the target population. Based on these results, we discussed a set of guidelines to help users select the best method for their datasets. We developed a robust and comprehensive software to allow for benchmarking comparisons between methods and proposed a computational framework for improving PRS performance in a dataset with a small sample size. This work is expected to inform the development of genomics applications in under-represented populations. PRSUP framework is available at: https://github.com/BiomedicalMachineLearning/VGP.


Asunto(s)
Estudio de Asociación del Genoma Completo , Herencia Multifactorial , Humanos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Vietnam , Genómica/métodos , Factores de Riesgo
2.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33649208

RESUMEN

Vaccine-based elicitation of broadly neutralizing antibodies holds great promise for preventing HIV-1 transmission. However, the key biophysical markers of improved antibody recognition remain uncertain in the diverse landscape of potential antibody mutation pathways, and a more complete understanding of anti-HIV-1 fusion peptide (FP) antibody development will accelerate rational vaccine designs. Here we survey the mutational landscape of the vaccine-elicited anti-FP antibody, vFP16.02, to determine the genetic, structural, and functional features associated with antibody improvement or fitness. Using site-saturation mutagenesis and yeast display functional screening, we found that 1% of possible single mutations improved HIV-1 envelope trimer (Env) affinity, but generally comprised rare somatic hypermutations that may not arise frequently in vivo. We observed that many single mutations in the vFP16.02 Fab could enhance affinity >1,000-fold against soluble FP, although affinity improvements against the HIV-1 trimer were more measured and rare. The most potent variants enhanced affinity to both soluble FP and Env, had mutations concentrated in antibody framework regions, and achieved up to 37% neutralization breadth compared to 28% neutralization of the template antibody. Altered heavy- and light-chain interface angles and conformational dynamics, as well as reduced Fab thermal stability, were associated with improved HIV-1 neutralization breadth and potency. We also observed parallel sets of mutations that enhanced viral neutralization through similar structural mechanisms. These data provide a quantitative understanding of the mutational landscape for vaccine-elicited FP-directed broadly neutralizing antibody and demonstrate that numerous antigen-distal framework mutations can improve antibody function by enhancing affinity simultaneously toward HIV-1 Env and FP.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Mutación , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/genética , Anticuerpos ampliamente neutralizantes/genética , Anticuerpos Anti-VIH/genética , VIH-1/genética , Humanos , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
3.
Chem Biodivers ; 21(5): e202400302, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38454878

RESUMEN

This study isolated pure compounds from Canna edulis aerial parts and assessed their antiplatelet and anticoagulant potential. Structural elucidation resulted in the identification of two new compounds: caneduloside A (1) and caneduloside B (2), and eleven known compounds: 6'-acetyl-3,6,2'-tri-p-coumaroyl sucrose (3), 6'-acetyl-3,6,2'-triferuloyl sucrose (4), tiliroside (5), afzelin (6), quercitrin (7), 2-hydroxycinnamaldehyde (8), cinnamic acid (9), 3,4-dimethoxycinnamic acid (10), dehydrovomifoliol (11), 4-hydroxy-3,5-dimethoxybenzaldehyde (12), and (S)-(-)-rosmarinic acid (13). Compounds 3, 4, 6-9, 13 were previously reported for antithrombotic properties. Hence, antithrombotic tests were conducted for 1, 2, 5, 10-12. All tested compounds demonstrated a dose-dependent antiaggregatory effect, and 10 and 12 were the most potent for both ADP and collagen activators. Additionally, 10 and 12 showed anticoagulant effects, with prolonged prothrombin time and activated partial thromboplastin time. The new compound 1 displayed antiplatelet and anticoagulant activity, while 2 mildly inhibited platelet aggregation. C. edulis is a potential source for developing antithrombotic agents.


Asunto(s)
Anticoagulantes , Componentes Aéreos de las Plantas , Inhibidores de Agregación Plaquetaria , Sacarosa , Anticoagulantes/farmacología , Anticoagulantes/química , Anticoagulantes/aislamiento & purificación , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/química , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Sacarosa/química , Sacarosa/farmacología , Sacarosa/metabolismo , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Humanos , Ésteres/química , Ésteres/farmacología , Ésteres/aislamiento & purificación , Agregación Plaquetaria/efectos de los fármacos , Myristicaceae/química , Relación Dosis-Respuesta a Droga , Estructura Molecular , Relación Estructura-Actividad , Animales
4.
Bioorg Med Chem Lett ; 31: 127673, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33161122

RESUMEN

Cassaine diterpenoids as erythrofordins A-C (1-3), pseudo-erythrosuamin (4), and erythrofordin U (5) isolated from the leaves of Vietnamese Erythrophleum fordii Oliver were tested cytotoxic activity against human leukemia cancer cells. The results showed that these metabolites exhibited dose-dependent cytotoxicity against human leukemia HL-60 and KG cells with IC50 values ranging from 15.2 ± 1.5 to 42.2 ± 3.6 µM. Treatment with erythrofordin B led to the apoptosis of HL-60 and KG cells due to the activation of caspase 3, caspase 9, and poly (ADP-ribose) polymerase (PARP). Erythrofordin B significantly increased Bak protein expression, but downregulated the anti-apoptotic protein Bcl-2, in HL-60 cells. In silico results demonstrated that erythrofordin B can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of -7.36 and -10.76 kcal/mol, respectively. These results indicated that the leaves of Vietnamese E. fordii, which contain cassaine diterpenoids, can induce the apoptosis of human leukemia cancer cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Fabaceae/química , Extractos Vegetales/farmacología , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Modelos Moleculares , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/química , Inhibidores de Poli(ADP-Ribosa) Polimerasas/aislamiento & purificación , Relación Estructura-Actividad
5.
J Contemp Dent Pract ; 22(11): 1275-1280, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35343453

RESUMEN

AIM AND OBJECTIVE: The current study aimed to investigate the effect of two nonsurgical periodontal treatment modalities on clinical periodontal parameters and glycemic control. MATERIALS AND METHODS: A randomized clinical trial was conducted with a sample of 64 type 2 diabetes mellitus (T2DM) patients with chronic periodontitis. Subjects were randomly assigned into two groups. Group I received oral hygiene instructions (OHI) at baseline and each recall visit. Group II received one-stage full-mouth scaling and root planning (SRP) combining OHI. At baseline, third month, and sixth month the plaque index (PlI), gingival index (GI), probing pocket depth (PPD), clinical attachment loss (CAL), and glycated hemoglobin (HbA1c) were recorded and analyzed. RESULTS: After treatment, two groups showed significant differences for all parameters at both assessed times (p <0.05). The OHI alone only demonstrated a slight reduction in GI in third month, with no significant changes for PlI and PPD indexes. However, Group I recorded the increased HbA1c and CAL values at 6-month follow-up (p <0.05). The combination of OHI and SRP exhibited a significant improvement in all periodontal values (p <0.05). Also, the HbA1C levels of Group II showed a significant reduction after treatment and were lower than those of Group I. CONCLUSIONS: Oral hygiene instructions only resulted in a better gingival condition of diabetic patients in the initial time. The nonsurgical periodontal therapy by combining SRP and OHI significantly improved both periodontal health and glycemic control. CLINICAL SIGNIFICANCE: Diabetic patients should be supplied with an effective OHI modality and a professional dental debridement.


Asunto(s)
Periodontitis Crónica , Diabetes Mellitus Tipo 2 , Periodontitis Crónica/complicaciones , Periodontitis Crónica/terapia , Raspado Dental/métodos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/terapia , Hemoglobina Glucada/análisis , Humanos , Aplanamiento de la Raíz/métodos
6.
Med Res Rev ; 39(3): 961-975, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30426515

RESUMEN

Narcolepsy is a rare, chronic neurological disease characterized by excessive daytime sleepiness, cataplexy, vivid hallucinations, and sleep paralysis. Narcolepsy occurs in approximately 1 of 3000 people, affecting mainly adolescents aged 15 to 30 years. Recently, people with narcolepsy were shown to exhibit extensive orexin/hypocretin neuronal loss. The orexin system regulates sleep/wake control via complex interactions with monoaminergic, cholinergic and GABA-ergic neuronal systems. Currently, no cure for narcolepsy exists, but some symptoms can be controlled with medication (eg, stimulants, antidepressants, etc). Orexin supplementation represents a more sophisticated way to treat narcolepsy because it addresses the underlying cause of the disease and not just the symptoms. Research on orexin supplementation in the treatment of sleep disorders has strongly increased over the past two decades. This review focuses on a brief description of narcolepsy, the mechanisms by which the orexin system regulates sleep/wake cycles, and finally, possible therapeutic options based on orexin supplementation in animal models and patients with narcolepsy.


Asunto(s)
Narcolepsia/tratamiento farmacológico , Orexinas/uso terapéutico , Animales , Trasplante de Células , Terapia Genética , Humanos , Narcolepsia/genética , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología
7.
BMC Complement Altern Med ; 17(1): 191, 2017 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-28376775

RESUMEN

BACKGROUND: The medicinal plant Siegesbeckia orientalis L. has been commonly used for the treatment of acute arthritis, rheumatism, and gout in Vietnam. However, pharmacological research of this plant associated with gout has not been reported. Anti-hyperuricemic and anti-inflammatory effects were evaluated and observed for the crude ethanol extract (CEE) of S. orientalis. Retention of these biological properties was found in a n-butanol-soluble fraction (BuOH fr.) of the extract, and therefore further biological and chemical investigations were undertaken on the BuOH fr. to support the medical relevance of this plant. METHODS: The aerial part of S. orientalis was obtained in the mountainous region of Vietnam. The crude ethanol extract (CEE) and its BuOH fr. were prepared from the plant materials. Anti-hyperuricemic activities of the CEE and BuOH fr. were tested in vivo using the model oxonate-induced hyperuricemia rats through determination of serum uric acid levels and inhibitory effects on xanthine oxidase (XO) in the rat liver. Anti-inflammatory activities of the BuOH fr. were also evaluated in vivo using carrageenan-induced paw edema and urate-induced synovitis in rats. Active components of the BuOH fr. were characterized by comparison of HPLC retention time (t R) and spectroscopic data (UV, 1H-NMR) with those of reference compounds. RESULTS: The CEE of S. orientalis displayed anti-hyperuricemic activity, and the BuOH fr. was found to be the most active portion of the extract. Further in vivo studies on this fraction showed 31.4% decrease of serum uric acid levels, 32.7% inhibition of xanthine oxidase (XO), 30.4% reduction of paw edema volume, symptomatic relief in urate-induced synovitis and significant analgesic effect at the dose of 120 mg/kg, as compared to the corresponding values of the control groups. Chemical analysis of the BuOH fr. revealed high phenolic content, identified as caffeic acid analogues and flavonones. CONCLUSIONS: This study suggested that anti-hyperuricemic and anti-inflammatory mechanism of S. orientalis is related to XO inhibitory effect of the phenolic components. Our findings support the use of this plant as the treatment of gout and other inflammatory diseases.


Asunto(s)
Analgésicos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Asteraceae/química , Hiperuricemia/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Analgésicos/aislamiento & purificación , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Carragenina , Modelos Animales de Enfermedad , Hiperuricemia/inducido químicamente , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Fenoles/química , Fenoles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Ratas , Ratas Wistar , Ácido Úrico/sangre , Vietnam , Xantina Oxidasa/antagonistas & inhibidores
8.
Int J Mol Sci ; 18(7)2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28686210

RESUMEN

The management of severe acetabular bone defects in revision reconstructive orthopedic surgery is challenging. In this study, cyclic precalcification (CP) treatment was used on both nanotube-surface Ti-mesh and a bone graft substitute for the acetabular defect model, and its effects were assessed in vitro and in vivo. Nanotube-Ti mesh coated with hydroxyapatite/ß-tricalcium phosphate (HA/ß-TCP) was manufactured by an anodizing and a sintering method, respectively. An 8 mm diameter defect was created on each acetabulum of eight rabbits, then treated by grafting materials and covered by Ti meshes. At four and eight weeks, postoperatively, biopsies were performed for histomorphometric analyses. The newly-formed bone layers under cyclic precalcified anodized Ti (CP-AT) meshes were superior with regard to the mineralized area at both four and eight weeks, as compared with that under untreated Ti meshes. Active bone regeneration at 2-4 weeks was stronger than at 6-8 weeks, particularly with treated biphasic ceramic (p < 0.05). CP improved the bioactivity of Ti meshes and biphasic grafting materials. Moreover, the precalcified nanotubular Ti meshes could enhance early contact bone formation on the mesh and, therefore, may reduce the collapse of Ti meshes into the defect, increasing the sufficiency of acetabular reconstruction. Finally, cyclic precalcification did not affect bone regeneration by biphasic grafting materials in vivo.


Asunto(s)
Acetábulo/patología , Hidroxiapatitas/farmacología , Nanotubos/química , Titanio/farmacología , Animales , Calcificación Fisiológica/efectos de los fármacos , Cerámica/farmacología , Materiales Biocompatibles Revestidos/farmacología , Masculino , Nanotubos/ultraestructura , Conejos , Cicatrización de Heridas/efectos de los fármacos
9.
J Oral Biol Craniofac Res ; 14(1): 92-97, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38293571

RESUMEN

Aim: This study aimed to assess the association between self-rated smile satisfaction and the smile dimensions among dental students. Method: An analytical cross-sectional study was conducted on 216 Vietnamese dental students. A standardized photograph was taken of each student with their frontal social smiles to assess aesthetic dimensions. A single-session self-administered questionnaire containing five questions about smile aesthetic satisfaction related to various aspects was administered to all students. Differences in smile characteristics and satisfaction scores between the two genders were evaluated. The impact of smile characteristics on satisfaction scores was assessed using multiple linear regression models. Results: Most dental students had a high smile line, parallel smile arcs, an upward upper lip curvature, a non-touching labiodental relationship, a dental midline that coincided with the midline of the face, and eight teeth displayed during smile. Most participants were satisfied with their smiles, and the self-rated satisfaction score was 67 out of 100. Self-perceived overall smile satisfaction was associated with the "smile arc", the "upper lip curvature", the "number of teeth displayed during smile", and the "dental midline". Female students had a statistically significant correlation between self-perception and smile characteristics, such as upper lip curvature, dental midline shift, and smile line. Conclusions: The smile arc, upper lip curvature, and dental midline shift affected self-perceived satisfaction among dental students. Female students showed an association between the smile parameters and self-perceived satisfaction.

10.
J Ethnopharmacol ; 330: 118226, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38670401

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing pulmonary disorder that has a poor prognosis and high mortality. Although there has been extensive effort to introduce several new anti-fibrotic agents in the past decade, IPF remains an incurable disease. Mimosa pudica L., an indigenous Vietnamese plant, has been empirically used to treat respiratory disorders. Nevertheless, the therapeutic effects of M. pudica (MP) on lung fibrosis and the mechanisms underlying those effects remain unclear. AIM OF THE STUDY: This study investigated the protective effect of a crude ethanol extract of the above-ground parts of MP against pulmonary fibrogenesis. MATERIALS AND METHODS: Inflammatory responses triggered by TNFα in structural lung cells were examined in normal human lung fibroblasts and A549 alveolar epithelial cells using Western blot analysis, reverse transcription-quantitative polymerase chain reaction assays, and immunocytochemistry. The epithelial-to-mesenchymal transition (EMT) was examined via cell morphology observations, F-actin fluorescent staining, gene and protein expression measurements, and a wound-healing assay. Anti-fibrotic assays including collagen release, differentiation, and measurements of fibrosis-related gene and protein expression levels were performed on TGFß-stimulated human lung fibroblasts and lung fibroblasts derived from mice with fibrotic lungs. Finally, in vitro anti-fibrotic activities were validated using a mouse model of bleomycin-induced pulmonary fibrosis. RESULTS: MP alleviated the inflammatory responses of A549 alveolar epithelial cells and lung fibroblasts, as revealed by inhibition of TNFα-induced chemotactic cytokine and chemokine expression, along with inactivation of the MAPK and NFκB signalling pathways. MP also partially reversed the TGFß-promoted EMT via downregulation of mesenchymal markers in A549 cells. Importantly, MP decreased the expression levels of fibrosis-related genes/proteins including collagen I, fibronectin, and αSMA; moreover, it suppressed collagen secretion and prevented myofibroblast differentiation in lung fibroblasts. These effects were mediated by FOXO3 stabilization through suppression of TGFß-induced ERK1/2 phosphorylation. MP consistently protected mice from the onset and progression of bleomycin-induced pulmonary fibrosis. CONCLUSION: This study explored the multifaceted roles of MP in counteracting the pathobiological processes of lung fibrosis. The results suggest that further evaluation of MP could yield candidate therapies for IPF.


Asunto(s)
Transición Epitelial-Mesenquimal , Proteína Forkhead Box O3 , Sistema de Señalización de MAP Quinasas , Extractos Vegetales , Fibrosis Pulmonar , Animales , Humanos , Masculino , Ratones , Células A549 , Antifibróticos/farmacología , Bleomicina , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Proteína Forkhead Box O3/metabolismo , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/inducido químicamente , Fibrosis Pulmonar Idiopática/patología , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones Endogámicos C57BL , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/inducido químicamente
11.
MAbs ; 15(1): 2168470, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36683172

RESUMEN

Despite the advances in surface-display systems for directed evolution, variants with high affinity are not always enriched due to undesirable biases that increase target-unrelated variants during biopanning. Here, our goal was to design a library containing improved variants from the information of the "weakly enriched" library where functional variants were weakly enriched. Deep sequencing for the previous biopanning result, where no functional antibody mimetics were experimentally identified, revealed that weak enrichment was partly due to undesirable biases during phage infection and amplification steps. The clustering analysis of the deep sequencing data from appropriate steps revealed no distinct sequence patterns, but a Bayesian machine learning model trained with the selected deep sequencing data supplied nine clusters with distinct sequence patterns. Phage libraries were designed on the basis of the sequence patterns identified, and four improved variants with target-specific affinity (EC50 = 80-277 nM) were identified by biopanning. The selection and use of deep sequencing data without undesirable bias enabled us to extract the information on prospective variants. In summary, the use of appropriate deep sequencing data and machine learning with the sequence data has the possibility of finding sequence space where functional variants are enriched.


Asunto(s)
Bacteriófagos , Biblioteca de Péptidos , Proteínas Portadoras , Teorema de Bayes , Estudios Prospectivos , Bacteriófagos/genética , Secuenciación de Nucleótidos de Alto Rendimiento
12.
Reprod Sci ; 30(9): 2876-2881, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37012491

RESUMEN

Male infertility is a growing health problem, which affects approximately 7% of the global male population. Nonobstructive azoospermia (NOA) is one of the most severe forms of male infertility caused by genetic defects, including chromosome structural abnormalities, Y chromosome microdeletions, or single-gene alterations. However, the etiology of up to 40% of NOA cases is unidentified. By whole-exome sequencing, we detected a homozygous 5-bp-deletion variant in exon 4 of the TEX12 gene (c.196-200del, p.L66fs, NM_031275.4) in two brothers with NOA of a nonconsanguineous Vietnamese family. This deletion variant of 5 nucleotides (ATTAG) results in a premature stop codon in exon 4 and truncation of the C-terminal. Segregation analysis by Sanger sequencing confirmed that the deletion variant was inherited in an autosomal recessive pattern. The 1st and 3rd infertile sons were homozygous for the deletion, whereas the 2nd fertile son and both parents were heterozygous. The new deletion mutation identified in TEX12 gene caused loss of function of TEX12 gene. The loss of TEX12 function has already caused infertility in male mice. Therefore, we concluded that the loss of TEX12 function may cause infertility in men. To our knowledge, this is the first case reported so far indicating disruption of human TEX12, which leads to infertility in men.


Asunto(s)
Azoospermia , Infertilidad Masculina , Humanos , Masculino , Animales , Ratones , Azoospermia/genética , Hermanos , Infertilidad Masculina/genética , Homocigoto
13.
Nat Prod Res ; 37(24): 4121-4130, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36661236

RESUMEN

One new compound, 4,7-dihydroxy-2-hydroxymethyl-5,6-dimethoxyanthraquinone (1), along with eight known compounds (2-9) were isolated from the methanol extracts of the aerial parts of Chamaecrista pumila (Lam.) K. Larsen. Their chemical structure was determined based on spectroscopic data interpretation and comparison with the reported data. The inhibitory effects of them on α-amylase and α-glucosidase were performed. The results showed that compounds 4, 6, 8, and 9 against potent α-glucosidase with the inhibition values of 98.14 ± 0.05, 98.19 ± 0.04, 97.01 ± 0.49, 84.43 ± 0.6% at 50 µM, respectively. Compounds 4 and 6 displayed significance against α-amylase at 200 µM with inhibition values of 22.35 ± 1.10 and 60.47 ± 0.91%.


Asunto(s)
Chamaecrista , Inhibidores de Glicósido Hidrolasas , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química , Hipoglucemiantes/farmacología , alfa-Glucosidasas/química , alfa-Amilasas/química , Extractos Vegetales/química , Componentes Aéreos de las Plantas/química
14.
Nat Commun ; 14(1): 7593, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37989731

RESUMEN

The HIV-1 fusion peptide (FP) represents a promising vaccine target, but global FP sequence diversity among circulating strains has limited anti-FP antibodies to ~60% neutralization breadth. Here we evolve the FP-targeting antibody VRC34.01 in vitro to enhance FP-neutralization using site saturation mutagenesis and yeast display. Successive rounds of directed evolution by iterative selection of antibodies for binding to resistant HIV-1 strains establish a variant, VRC34.01_mm28, as a best-in-class antibody with 10-fold enhanced potency compared to the template antibody and ~80% breadth on a cross-clade 208-strain neutralization panel. Structural analyses demonstrate that the improved paratope expands the FP binding groove to accommodate diverse FP sequences of different lengths while also recognizing the HIV-1 Env backbone. These data reveal critical antibody features for enhanced neutralization breadth and potency against the FP site of vulnerability and accelerate clinical development of broad HIV-1 FP-targeting vaccines and therapeutics.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , VIH-1/genética , Anticuerpos Anti-VIH , Anticuerpos Neutralizantes , Péptidos , Secuencia de Aminoácidos , Vacunas de Subunidad , Pruebas de Neutralización , Productos del Gen env del Virus de la Inmunodeficiencia Humana
15.
Sci Total Environ ; 904: 166330, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37591389

RESUMEN

Although sediments are considered to be a major sink for microplastics (MP), there is still a relative lack of knowledge on the factors that influence the occurrence and abundance of MP in riverine sediments. The present study investigated the occurrence and distribution of MP in riverine sediments collected at twelve sites representative of different populated and urbanized rivers (To Lich, Nhue and Day Rivers) located in the Red River Delta (RRD, Vietnam, during dry and rainy seasons. MP concentrations ranged from 1600 items kg-1 dw to 94,300 items kg-1dw. Fiber shape dominated and MP were made of polypropylene (PP) and polyethylene (PE) predominantly. An absence of seasonal effect was observed for both fragments and fibers for each rivers. Decreasing MP concentrations trend was evidenced from the To Lich River, to the Nhue River and to the Day River, coupled with a decreasing fiber length and an increasing fragment area in the surface sediment from upstream to downstream. Content of organic matter was correlated to MP concentrations suggesting that, high levels of organic matter could be MP hotspots in urban rivers. Also, high population density as well as in highly residential areas are related to higher MP concentrations in sediments. Finally, a MP high ecological risk (RI: 866 to 4711) was calculated in the RDD.

16.
Heliyon ; 8(3): e09070, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35287327

RESUMEN

Balanophora laxiflora, a medicinal plant traditionally used to treat fever, pain, and inflammation in Vietnam, has been reported to possess prominent anti-inflammatory activity. This study examined the active constituents and molecular mechanisms underlying these anti-inflammatory effects using bioactivity-guided isolation in combination with cell-based assays and animal models of inflammation. Among the isolated compounds, the triterpenoid (21α)-22-hydroxyhopan-3-one (1) showed the most potent inhibitory effect on COX-2 expression in LPS-stimulated Raw 264.7 macrophages. Furthermore, 1 suppressed the expression of the inflammatory mediators iNOS, IL-1ß, INFß, and TNFα in activated Raw 264.7 macrophages and alleviated the inflammatory response in carrageenan-induced paw oedema and a cotton pellet-induced granuloma model. Mechanistically, the anti-inflammatory effects of 1 were mediated via decreasing cellular reactive oxygen species (ROS) levels by inhibiting NADPH oxidases (NOXs) and free radical scavenging activities. By downregulating ROS signalling, 1 reduced the activation of MAPK signalling pathways, leading to decreased AP-1-dependent transcription of inflammatory mediators. These findings shed light on the chemical constituents that contribute to the anti-inflammatory actions of B. laxiflora and suggest that 1 is a promising candidate for treating inflammation-related diseases.

17.
Int J Pharm ; 616: 121525, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35104597

RESUMEN

Berberine (BBR) is a plant-origin quaternary isoquinoline alkaloid presenting exogenous cholesterol lowering and anti-hyperlipidemia therapeutic effects. The aim of this study was to design and generate BBR-loaded proliposomes (PLs) as solid templates for high-dose liposomes and consequently, to enhance the oral bioavailability and therapeutic effect of BBR. An air-suspension coating (layering) method was used for generating BBR-loaded PLs. The size, distribution size, morphology, and entrapment efficiency (EE) of the final reconstituted liposomes were assessed. The oral bioavailability and endogenous cholesterol lowering effects of BBR loaded in liposomes were investigated in rats and mice, respectively. The BBR-loaded PLs showed a smooth BBR-embedded film around micron-scale carrier particles (mannitol). The reconstituted BBR-loaded liposomes had a nano-scale average size (116.6 ± 5.8 nm), narrow size distribution (polydispersity index, PDI 0.269 ± 0.038), and high EE (87.8 ± 1.0%). The oral bioavailability of reconstituted BBR-loaded liposomes at a dose of 100 mg/kg in rats was increased even 628% compared to that obtained with pure BBR (according to 90% confidence interval). The BBR-loaded liposomes at the daily oral dose 100 mg/kg in P-407- reduced total cholesterol, triglycerides and low-density lipoprotein cholesterol (LDL-C) in hyperlipidemic mice by 15.8%, 38.2%, and 57.0%, respectively.


Asunto(s)
Berberina , Animales , Berberina/química , Colesterol , LDL-Colesterol , Modelos Animales de Enfermedad , Liposomas/química , Ratones , Ratas
18.
J Exp Med ; 219(8)2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35736810

RESUMEN

The monoclonal antibody CIS43 targets the Plasmodium falciparum circumsporozoite protein (PfCSP) and prevents malaria infection in humans for up to 9 mo following a single intravenous administration. To enhance the potency and clinical utility of CIS43, we used iterative site-saturation mutagenesis and DNA shuffling to screen precise gene-variant yeast display libraries for improved PfCSP antigen recognition. We identified several mutations that improved recognition, predominately in framework regions, and combined these to produce a panel of antibody variants. The most improved antibody, CIS43_Var10, had three mutations and showed approximately sixfold enhanced protective potency in vivo compared to CIS43. Co-crystal and cryo-electron microscopy structures of CIS43_Var10 with the peptide epitope or with PfCSP, respectively, revealed functional roles for each of these mutations. The unbiased site-directed mutagenesis and screening pipeline described here represent a powerful approach to enhance protective potency and to enable broader clinical use of antimalarial antibodies.


Asunto(s)
Antimaláricos , Vacunas contra la Malaria , Anticuerpos Antiprotozoarios , Antimaláricos/farmacología , Microscopía por Crioelectrón , Humanos , Plasmodium falciparum , Proteínas Protozoarias , Saccharomyces cerevisiae/genética
19.
Biochem Soc Trans ; 39(6): 1693-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22103509

RESUMEN

The LINC (linker of nucleoskeleton and cytoskeleton) complex is a proposed mechanical link tethering the nucleo- and cyto-skeleton via the NE (nuclear envelope). The LINC components emerin, lamin A/C, SUN1, SUN2, nesprin-1 and nesprin-2 interact with each other at the NE and also with other binding partners including actin filaments and B-type lamins. Besides the mechanostructural functions, the LINC complex is also involved in signalling pathways and gene regulation. Emerin was the first LINC component associated with a human disease, namely EDMD (Emery-Dreifuss muscular dystrophy). Later on, other components of the LINC complex, such as lamins A/C and small isoforms of nesprin-1 and nesprin-2, were found to be associated with EDMD, reflecting a genetic heterogeneity that has not been resolved so far. Only approximately 46% of the EDMD patients can be linked to genes of LINC and non-LINC components, pointing to further genes involved in the pathology of EDMD. Obvious candidates are the LINC proteins SUN1 and SUN2. Recently, screening of binding partners of LINC components as candidates identified LUMA (TMEM43), encoding a binding partner of emerin and lamins, as a gene involved in atypical EDMD. Nevertheless, such mutations contribute only to a very small fraction of EDMD patients. EDMD-causing mutations in STA/EMD (encoding emerin) that disrupt emerin binding to Btf (Bcl-2-associated transcription factor), GCL (germ cell-less) and BAF (barrier to autointegration factor) provide the first glimpses into LINC being involved in gene regulation and thus opening new avenues for functional studies. Thus the association of LINC with human disease provides tools for understanding its functions within the cell.


Asunto(s)
Enfermedad , Complejos Multiproteicos/metabolismo , Secuencia de Bases , Humanos , Lamina Tipo A/genética , Datos de Secuencia Molecular , Distrofia Muscular de Emery-Dreifuss/metabolismo
20.
Protein Eng Des Sel ; 32(11): 503-511, 2019 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-32705123

RESUMEN

In protein engineering, generation of mutagenesis libraries is a key step to study the functions of mutants. To generate mutants with a desired composition of amino acids (AAs), a codon consisting of a mixture of nucleotides is widely applied. Several computational methods have been proposed to calculate a codon nucleotide composition for generating a given amino acid profile based on mathematical optimization. However, these previous methods need to manually tune weights of amino acids in objective functions, which are time-consuming and, more importantly, lack publicly available software implementations. Here, we develop CodonAdjust, a software to adjust a codon nucleotide composition for mimicking a given amino acid profile. We propose different options of CodonAdjust, which provide various customizations in practical scenarios such as setting a guaranteeing threshold for the frequencies of amino acids without any manual tasks. We demonstrate the capability of CodonAdjust in the experiments on the complementarity-determining regions (CDRs) of antibodies and T-cell receptors (TCRs) as well as millions of amino acid profiles from Pfam. These results suggest that CodonAdjust is a productive software for codon design and may accelerate library generation. CodonAdjust is freely available at https://github.com/tiffany-nguyen/CodonAdjust. Paper edited by Dr. Jeffery Saven, Board Member for PEDS.


Asunto(s)
Simulación por Computador , Biblioteca de Genes , Mutagénesis , Ingeniería de Proteínas , Programas Informáticos , Regiones Determinantes de Complementariedad/química , Regiones Determinantes de Complementariedad/genética , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/genética
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