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1.
Cell ; 169(5): 891-904.e15, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28525756

RESUMO

While neutralizing antibodies are highly effective against ebolavirus infections, current experimental ebolavirus vaccines primarily elicit species-specific antibody responses. Here, we describe an immunization-elicited macaque antibody (CA45) that clamps the internal fusion loop with the N terminus of the ebolavirus glycoproteins (GPs) and potently neutralizes Ebola, Sudan, Bundibugyo, and Reston viruses. CA45, alone or in combination with an antibody that blocks receptor binding, provided full protection against all pathogenic ebolaviruses in mice, guinea pigs, and ferrets. Analysis of memory B cells from the immunized macaque suggests that elicitation of broadly neutralizing antibodies (bNAbs) for ebolaviruses is possible but difficult, potentially due to the rarity of bNAb clones and their precursors. Unexpectedly, germline-reverted CA45, while exhibiting negligible binding to full-length GP, bound a proteolytically remodeled GP with picomolar affinity, suggesting that engineered ebolavirus vaccines could trigger rare bNAb precursors more robustly. These findings have important implications for developing pan-ebolavirus vaccine and immunotherapeutic cocktails.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Vacinas contra Ebola/imunologia , Doença pelo Vírus Ebola/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Regiões Determinantes de Complementaridade , Reações Cruzadas , Ebolavirus/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Feminino , Furões , Cobaias , Fragmentos Fab das Imunoglobulinas/ultraestrutura , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares
2.
Arch Microbiol ; 206(3): 97, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349544

RESUMO

Cordyceps militaris is a well-known medicinal mushroom in Asian countries. This edible fungus has been widely exploited for traditional medicine and functional food production. C. militaris is a heterothallic fungus that requires both the mating-type loci, MAT1-1 and MAT1-2, for fruiting body formation. However, recent studies also indicated two groups of C. militaris, including monokaryotic strains carrying only MAT1-1 in their genomes and heterokaryotic strains harboring both MAT1-1 and MAT1-2. These strain groups are able to produce fruiting bodies under suitable cultivating conditions. In previous work, we showed that monokaryotic strains are more stable than heterokaryotic strains in fruiting body formation through successive culturing generations. In this study, we report a high cordycepin-producing monokaryotic C. militaris strain (HL8) collected in Vietnam. This strain could form normal fruiting bodies with high biological efficiency and contain a cordycepin content of 14.43 mg/g lyophilized fruiting body biomass. The ethanol extraction of the HL8 fruiting bodies resulted in a crude extract with a cordycepin content of 69.15 mg/g. Assays of cytotoxic activity on six human cancer cell lines showed that the extract inhibited the growth of all these cell lines with the IC50 values of 6.41-11.51 µg/mL. Notably, the extract significantly reduced cell proliferation and promoted apoptosis of breast cancer cells. Furthermore, the extract also exhibited strong antifungal activity against Malassezia skin yeasts and the citrus postharvest pathogen Penicillium digitatum. Our work provides a promising monokaryotic C. militaris strain as a bioresource for medicine, cosmetics, and fruit preservation.


Assuntos
Antineoplásicos , Cordyceps , Neoplasias , Penicillium , Humanos , Penicillium/genética , Carpóforos
3.
PLoS Genet ; 17(3): e1009392, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33661925

RESUMO

The natural history of tuberculosis (TB) is characterized by a large inter-individual outcome variability after exposure to Mycobacterium tuberculosis. Specifically, some highly exposed individuals remain resistant to M. tuberculosis infection, as inferred by tuberculin skin test (TST) or interferon-gamma release assays (IGRAs). We performed a genome-wide association study of resistance to M. tuberculosis infection in an endemic region of Southern Vietnam. We enrolled household contacts (HHC) of pulmonary TB cases and compared subjects who were negative for both TST and IGRA (n = 185) with infected individuals (n = 353) who were either positive for both TST and IGRA or had a diagnosis of TB. We found a genome-wide significant locus on chromosome 10q26.2 with a cluster of variants associated with strong protection against M. tuberculosis infection (OR = 0.42, 95%CI 0.35-0.49, P = 3.71×10-8, for the genotyped variant rs17155120). The locus was replicated in a French multi-ethnic HHC cohort and a familial admixed cohort from a hyper-endemic area of South Africa, with an overall OR for rs17155120 estimated at 0.50 (95%CI 0.45-0.55, P = 1.26×10-9). The variants are located in intronic regions and upstream of C10orf90, a tumor suppressor gene which encodes an ubiquitin ligase activating the transcription factor p53. In silico analysis showed that the protective alleles were associated with a decreased expression in monocytes of the nearby gene ADAM12 which could lead to an enhanced response of Th17 lymphocytes. Our results reveal a novel locus controlling resistance to M. tuberculosis infection across different populations.


Assuntos
Cromossomos Humanos Par 10 , Resistência à Doença/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Mycobacterium tuberculosis , Locos de Características Quantitativas , Tuberculose/genética , Tuberculose/microbiologia , Alelos , Biologia Computacional/métodos , França , Genótipo , Humanos , Metanálise como Assunto , Grupos Populacionais/genética , África do Sul , Vietnã
4.
J Infect Dis ; 228(Suppl 7): S701-S711, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37474248

RESUMO

Marburg virus (MARV) causes a hemorrhagic fever disease in human and nonhuman primates with high levels of morbidity and mortality. Concerns about weaponization of aerosolized MARV have spurred the development of nonhuman primate (NHP) models of aerosol exposure. To address the potential threat of aerosol exposure, a monoclonal antibody that binds MARV glycoprotein was tested, MR186YTE, for its efficacy as a prophylactic. MR186YTE was administered intramuscularly to NHPs at 15 or 5 mg/kg 1 month prior to MARV aerosol challenge. Seventy-five percent (3/4) of the 15 mg/kg dose group and 50% (2/4) of the 5 mg/kg dose group survived. Serum analyses showed that the NHP dosed with 15 mg/kg that succumbed to infection developed an antidrug antibody response and therefore had no detectable MR186YTE at the time of challenge. These results suggest that intramuscular dosing of mAbs may be a clinically useful prophylaxis for MARV aerosol exposure.


Assuntos
Doença do Vírus de Marburg , Marburgvirus , Animais , Humanos , Anticorpos Monoclonais , Primatas , Aerossóis
5.
Health Commun ; : 1-14, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095061

RESUMO

This experimental study investigates the effects of several heuristic cues and systematic factors on users' misinformation susceptibility in the context of health news. Specifically, it examines whether author credentials, writing style, and verification check flagging influence participants' intent to follow article behavioral recommendations provided by the article, perceived article credibility, and sharing intent. Findings suggest that users rely only on verification checks (passing/failing) in assessing information credibility. Of the two antecedents to systematic processing, social media self-efficacy moderates the links between verification and participants' susceptibility. Theoretical and practical implications are discussed.

6.
Rep Pract Oncol Radiother ; 28(6): 784-793, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38515819

RESUMO

Background: Volumetric modulated arc therapy (VMAT) and 3D image-guided brachytherapy (3D-IGBT) have recently been introduced in Vietnam for the treatment of locally advanced cervical cancer. This study aims to assess the outcomes and toxicities of chemoradiation using VMAT followed by 3D-IGBT in Vietnamese cervical cancer patients. Materials and methods: A prospective interventional study on 72 patients with 2018 International Federation of Gynecology and Obstetrics (FIGO) stage IB3-IIIC2 disease who underwent concurrent chemoradiation using VMAT, followed by 3D-IGBT according to EMBRACE-II protocol. Primary endpoints were locoregional control; secondary endpoints were systemic control and toxicity. Results: Median body volume received 43 Gy was 1589.1 cm3 (range 1214.8-2574.8). Median high-risk clinical target volume (CTV-HR) was 18.8 cm3 (range 8.6-61.2) with a median dose to 90% (D90) of CTV-HR of 90.6 Gy (range 86.8-99.6). Mean doses to 2cc (D2cc) of bladder, rectum, and sigmoid were 75.8, 55.2, and 62.1 Gy, respectively. At median 19-month follow-up (range 12-25), locoregional control and systemic control were 95.8% and 81.9%, respectively. Systemic control was the lowest in N2 disease (54.5%). Grade ≥ 3 acute toxicities were less than 10%, except neutropenia (31.9%). Extended-field radiation increased significantly nausea, fatigue, and thrombocytopenia. No grade ≥ 3 proctitis or cystitis; 8.3% had grade 3 vaginal stenosis. Conclusions: VMAT-based chemoradiation therapy followed by 3D-IGBT achieved high locoregional control with manageable toxicities in locally advanced cervical cancer. Systemic control correlated with disease stage.

7.
PLoS Pathog ; 16(8): e1008818, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776973

RESUMO

Leprosy is a chronic disease caused by Mycobacterium leprae. Worldwide, more than 200,000 new patients are affected by leprosy annually, making it the second most common mycobacterial disease after tuberculosis. The MHC/HLA region has been consistently identified as carrying major leprosy susceptibility variants in different populations at times with inconsistent results. To establish the unambiguous molecular identity of classical HLA class I and class II leprosy susceptibility factors, we applied next-generation sequencing to genotype with high-resolution 11 HLA class I and class II genes in 1,155 individuals from a Vietnamese leprosy case-control sample. HLA alleles belonging to an extended haplotype from HLA-A to HLA-DPB1 were associated with risk to leprosy. This susceptibility signal could be reduced to the HLA-DRB1*10:01~ HLA-DQA1*01:05 alleles which were in complete linkage disequilibrium (LD). In addition, haplotypes containing HLA-DRB3~ HLA-DRB1*12:02 and HLA-C*07:06~ HLA-B*44:03~ HLA-DRB1*07:01 alleles were found as two independent protective factors for leprosy. Moreover, we replicated the previously associated HLA-DRB1*15:01 as leprosy risk factor and HLA-DRB1*04:05~HLA-DQA1*03:03 as protective alleles. When we narrowed the analysis to the single amino acid level, we found that the associations of the HLA alleles were largely captured by four independent amino acids at HLA-DRß1 positions 57 (D) and 13 (F), HLA-B position 63 (E) and HLA-A position 19 (K). Hence, analyses at the amino acid level circumvented the ambiguity caused by strong LD of leprosy susceptibility HLA alleles and identified four distinct leprosy susceptibility factors.


Assuntos
Aminoácidos/genética , Predisposição Genética para Doença , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Hanseníase/patologia , Mutação , Adolescente , Adulto , Feminino , Haplótipos , Humanos , Hanseníase/genética , Masculino , Adulto Jovem
8.
PLoS Pathog ; 16(5): e1008565, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32421744

RESUMO

Leprosy is a chronic infectious disease of the skin and peripheral nerves with a strong genetic predisposition. Recent genome-wide approaches have identified numerous common variants associated with leprosy, almost all in the Chinese population. We conducted the first family-based genome-wide association study of leprosy in 622 affected offspring from Vietnam, followed by replication in an independent sample of 1181 leprosy cases and 668 controls of the same ethnic origin. The most significant results were observed within the HLA region, in which six SNPs displayed genome-wide significant associations, all of which were replicated in the independent case/control sample. We investigated the signal in the HLA region in more detail, by conducting a multivariate analysis on the case/control sample of 319 GWAS-suggestive HLA hits for which evidence for replication was obtained. We identified three independently associated SNPs, two located in the HLA class I region (rs1265048: OR = 0.69 [0.58-0.80], combined p-value = 5.53x10-11; and rs114598080: OR = 1.47 [1.46-1.48], combined p-value = 8.77x10-13), and one located in the HLA class II region (rs3187964 (OR = 1.67 [1.55-1.80], combined p-value = 8.35x10-16). We also validated two previously identified risk factors for leprosy: the missense variant rs3764147 in the LACC1 gene (OR = 1.52 [1.41-1.63], combined p-value = 5.06x10-14), and the intergenic variant rs6871626 located close to the IL12B gene (OR = 0.73 [0.61-0.84], combined p-value = 6.44x10-8). These results shed new light on the genetic control of leprosy, by dissecting the influence of HLA SNPs, and validating the independent role of two additional variants in a large Vietnamese sample.


Assuntos
Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Hanseníase/genética , Polimorfismo de Nucleotídeo Único , Feminino , Estudo de Associação Genômica Ampla , Humanos , Subunidade p40 da Interleucina-12/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Hanseníase/epidemiologia , Masculino
9.
Proc Natl Acad Sci U S A ; 116(31): 15616-15624, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31308240

RESUMO

Type-1 reactions (T1R) are pathological inflammatory episodes and main contributors to nerve damage in leprosy. Here, we evaluate the genewise enrichment of rare protein-altering variants in 7 genes where common variants were previously associated with T1R. We selected 474 Vietnamese leprosy patients of which 237 were T1R-affected and 237 were T1R-free matched controls. Genewise enrichment of nonsynonymous variants was tested with both kernel-based (sequence kernel association test [SKAT]) and burden methods. Of the 7 genes tested 2 showed statistical evidence of association with T1R. For the LRRK2 gene an enrichment of nonsynonymous variants was observed in T1R-free controls (PSKAT-O = 1.6 × 10-4). This genewise association was driven almost entirely by the gain-of-function variant R1628P (P = 0.004; odds ratio = 0.29). The second genewise association was found for the Parkin coding gene PRKN (formerly PARK2) where 7 rare variants were enriched in T1R-affected cases (PSKAT-O = 7.4 × 10-5). Mutations in both PRKN and LRRK2 are known causes of Parkinson's disease (PD). Hence, we evaluated to what extent such rare amino acid changes observed in T1R are shared with PD. We observed that amino acids in Parkin targeted by nonsynonymous T1R-risk mutations were also enriched for mutations implicated in PD (P = 1.5 × 10-4). Hence, neuroinflammation in PD and peripheral nerve damage due to inflammation in T1R share overlapping genetic control of pathogenicity.


Assuntos
Hanseníase , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Mutação , Doença de Parkinson , Ubiquitina-Proteína Ligases , Feminino , Humanos , Hanseníase/genética , Hanseníase/metabolismo , Hanseníase/patologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Masculino , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
10.
Microsurgery ; 42(7): 659-667, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35716021

RESUMO

BACKGROUND: Treatment for large defects in the non-weight-bearing Achilles tendon and soft tissues remains a reconstructive challenge. The free composite anterolateral thigh flap (ALT) with fascia lata (FL) has been indicated in the single-stage reconstruction of the Achilles tendon and soft tissue defect and this technique remain some disadvantages, such as the inability to perform primary flap thinning, requiring secondary flap thinning, and the delayed normalization of the range of motion of the ankle joint. The free chimeric ALT flap with FL was introduced as a novel alternative with many advantages in reconstructing the Achilles tendon and soft tissue defects. This paper reports the reconstruction of the massive Achilles tendon and overlying skin defects using free chimeric ALT flaps with FL. METHODS: From June 2017 to October 2020, we performed on a series of 5 patients receiving free chimeric ALT flaps with FL to reconstruct the Achilles tendon and soft tissue defects. The age of patients ranged from 43 to 62 years old. All five patients had full-layer defects of the Achilles tendon with infection. The sizes of the skin defects ranged from 6 × 4 cm to 12 × 10 cm. The perforators from the descending branch of the lateral circumflex femoral arteries are located using a handheld Doppler. The perforators help to design the outline of the ALT flap and fascia flap. The skin flap was thinned under microscopy if the flap was too thick. The anastomosis was accomplished before insetting the flaps into the defect. RESULTS: The size of the ALT flap ranged from 10 × 5 cm to 15 × 12 cm, and the size of the FL flap ranged from 7 × 4 cm to 10 × 8 cm. The mean perforator length for the skin flap and fascia lata was 3.3 cm (range, 2.5-5.0 cm) and 5.3 cm (range, 3.5-7.0 cm), respectively. Four patients received skin flap thinning up to 57%-79% of the flap thickness, while one patient did not need to debulk. The thickness of the ALT flap ranged from 6 to 13 mm. All the flaps survived completely and postoperative courses were uneventful without any complications. The follow-up time ranged from 12 to 51 months. All patients were able to stand and ambulate, and they were satisfied with the reconstructive results. CONCLUSIONS: The free thin chimeric ALT with FL flap is appeared to be an appropriate treatment for the massive Achilles tendon and overlying skin defects. This may be a practical approach to improve the functional outcomes of patients with infected massive Achilles tendon and overlying skin defects.


Assuntos
Tendão do Calcâneo , Retalhos de Tecido Biológico , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Tendão do Calcâneo/cirurgia , Adulto , Fascia Lata/transplante , Retalhos de Tecido Biológico/cirurgia , Humanos , Pessoa de Meia-Idade , Retalho Perfurante/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Lesões dos Tecidos Moles/cirurgia , Coxa da Perna/cirurgia
11.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216132

RESUMO

Duchenne muscular dystrophy (DMD) is the most common and cureless muscle pediatric genetic disease, which is caused by the lack or the drastically reduced expression of dystrophin. Experimental therapeutic approaches for DMD have been mainly focused in recent years on attempts to restore the expression of dystrophin. While significant progress was achieved, the therapeutic benefit of treated patients is still unsatisfactory. Efficiency in gene therapy for DMD is hampered not only by incompletely resolved technical issues, but likely also due to the progressive nature of DMD. It is indeed suspected that some of the secondary pathologies, which are evolving over time in DMD patients, are not fully corrected by the restoration of dystrophin expression. We recently identified perturbations of the mevalonate pathway and of cholesterol metabolism in DMD patients. Taking advantage of the mdx model for DMD, we then demonstrated that some of these perturbations are improved by treatment with the cholesterol-lowering drug, simvastatin. In the present investigation, we tested whether the combination of the restoration of dystrophin expression with simvastatin treatment could have an additive beneficial effect in the mdx model. We confirmed the positive effects of microdystrophin, and of simvastatin, when administrated separately, but detected no additive effect by their combination. Thus, the present study does not support an additive beneficial effect by combining dystrophin restoration with a metabolic normalization by simvastatin.


Assuntos
Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/terapia , Sinvastatina/administração & dosagem , Animais , Modelos Animais de Doenças , Terapia Genética/métodos , Masculino , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético/efeitos dos fármacos
12.
Biochem Biophys Res Commun ; 553: 85-91, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33765558

RESUMO

Glucose-6-phosphate dehydrogenase is the first enzyme in the pentose phosphate pathway. The reaction catalyzed by the enzyme is considered to be the main source of reducing power for nicotinamide adenine dinucleotide phosphate (NADPH) and is a precursor of 5-carbon sugar used by cells. To uncover the structural features of the enzyme, we determined the crystal structures of glucose-6-phosphate dehydrogenase from Kluyveromyces lactis (KlG6PD) in both the apo form and a binary complex with its substrate glucose-6-phosphate. KlG6PD contains a Rossman-like domain for cofactor NADPH binding; it also presents a typical antiparallel ß sheet at the C-terminal domain with relatively the same pattern as those of other homologous structures. Moreover, our structural and biochemical analyses revealed that Lys153 contributes significantly to substrate G6P recognition. This study may provide insights into the structural variation and catalytic features of the G6PD enzyme.


Assuntos
Glucosefosfato Desidrogenase/química , Glucosefosfato Desidrogenase/metabolismo , Kluyveromyces/enzimologia , Sequência de Aminoácidos , Apoenzimas/química , Apoenzimas/genética , Apoenzimas/metabolismo , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Glucosefosfato Desidrogenase/genética , Cinética , Modelos Moleculares , Mutagênese , Relação Estrutura-Atividade , Especificidade por Substrato
13.
Exp Dermatol ; 30(8): 1033-1050, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34003523

RESUMO

Melanocytes originate in the neural crest as precursor cells which then migrate and proliferate to reach their destination where they differentiate into pigment-producing cells. Melanocytes not only determine the colour of hair, skin and eyes but also protect against the harmful effects of UV irradiation. The establishment of the melanocyte lineage is regulated by a defined set of transcription factors and signalling pathways that direct the specific gene expression programmes underpinning melanoblast specification, survival, migration, proliferation and differentiation. In addition, epigenetic modifiers and replacement histones play key roles in regulating gene expression and its timing during the different steps of this process. Here, we discuss the evidence for the role of epigenetic regulators in melanocyte development and function and how they interact with transcription factors and signalling pathways to establish and maintain this important cell lineage.


Assuntos
Epigênese Genética , Homeostase/genética , Melanócitos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Linhagem da Célula , Humanos , Camundongos
14.
Health Commun ; 36(7): 909-919, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32013571

RESUMO

Guided by the health risk communication literature and the social identity model of deindividualization effects, this study examines whether and how concurrent exposure to health news articles and congruent/incongruent comments posted by anonymous others may affect news viewers' personal risk perception, societal risk perception, and intention to communicate about health risk issues. Two controlled experiments were conducted in Vietnam concerning two controversial health risk issues, including ear picking and child corporal punishment. Results showed a significant interaction effect between comments and perceived similarity on personal risk perception and societal risk perception, such that comments influenced both types of risk perception when viewers perceived that anonymous commenters were ingroup members. Results also indicated the joint effect of comments and perceived similarity on participants' intention to communicate, mediated by their personal risk perception and societal risk perception. Theoretical and practical implications were discussed.


Assuntos
Comunicação em Saúde , Intenção , Criança , Humanos , Percepção
15.
J Environ Manage ; 280: 111652, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33229112

RESUMO

Phosphorus (P) concentration beyond threshold limit can trigger eutrophication in stagnant water bodies nevertheless it is an indispensable macronutrient for aquatic life. Even in low P concentration (≤1 mg L-1), P can be detrimental for ecosystem's health, but this aspect has not been thoroughly investigated. The elimination of low P content is rather expensive or complex. Therefore, a unique and sustainable approach has been proposed in which valorized bivalve seashells can be used for the removal of low P content. Initially, acicular shaped aragonite particles (~21 µm) with an aspect ratio of around 21 have been synthesized through the wet carbonation process and used to treat aqueous solutions containing P in low concentration (P ≤ 1 mg L-1). Response surface methodology based Box-Behnken design has been employed for optimization study which revealed that with aragonite dosage (140 mg), equilibrium pH (~10.15), and temperature (45 °C), a phosphorus removal efficiency of ~97% can be obtained in 10 h. The kinetics and isotherm studies have also been carried out (within the range P ≤ 1 mg L-1) to investigate a probable removal mechanism. Also, aragonite demonstrates higher selectivity (>70%) towards phosphate with coexisting anions such as nitrate, chloride, sulfate, and carbonate. Through experimental data, elemental mapping, and molecular dynamic simulation, it has been observed that the removal mechanism involved a combination of electrostatic adsorption of Ca2+ ions on aragonite surface and chemical interaction between the calcium and phosphate ions. The present work demonstrates a sustainable and propitious potential of seashell derived aragonite for the removal of low P content in aqueous solution along with its unconventional mechanistic approach.


Assuntos
Carbonato de Cálcio , Poluentes Químicos da Água , Adsorção , Exoesqueleto , Animais , Ecossistema , Concentração de Íons de Hidrogênio , Cinética , Fosfatos , Fósforo , Água
16.
Exp Dermatol ; 29(1): 107-111, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31587370

RESUMO

Studies have shown that wound pH is a potentially influential factor in the healing process. Due to the flaws of traditional pH measurement approaches, wound pH measurement has not become part of current standard of care. A near-infrared pH-sensitive ratiometric film was created and characterized for measuring wound pH. This film was fabricated by physically absorbing poly (N-isopropyl Acrylamide) nanoparticles conjugated with pH-sensitive (CypHer5E) and pH-insensitive (Cy7) fluorescent dyes into 2-hydroxyethyl methacrylate hydrogel film. The pH pattern on wounds can be indirectly measured by pressing freshly discarded wound dressing on top of the pH-sensitive film and imaging it. In vitro tests show that the film can accurately and rapidly detect a wide range of pH (from pH 4 to 8) in wound milieu. Further, patient studies showed that, by measuring pH on wound contact side of discarded wound gauze, the pH and its non-homogeneous distribution on wounds can be indirectly determined. By comparing patients with different wound conditions, we find that near-infrared pH sensing film can be used to measure wound exudate pH with high accuracy and efficiency. In addition, wound pH determination can provide an accurate assessment of wound healing activity in real time.


Assuntos
Exsudatos e Transudatos/química , Cicatrização/fisiologia , Acrilamidas/química , Bandagens , Corantes Fluorescentes , Humanos , Hidrogéis , Concentração de Íons de Hidrogênio , Metacrilatos , Nanopartículas , Pele/lesões , Dermatopatias/fisiopatologia , Ferimentos e Lesões/fisiopatologia
17.
Phys Chem Chem Phys ; 22(6): 3661-3674, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32002524

RESUMO

We have systematically investigated the magnetization reversal characteristics and magnetoresistance of continuous and nanoporous [Co/Pd]5-IrMn multilayered thin films with perpendicular magnetic anisotropy at different temperatures (4-300 K). For their nanostructuring, porosity was induced by means of deposition onto templates of anodized titania with small (∼30 nm in diameter) homogeneously distributed pores. The magnetization reversal and magnetoresistance of the porous films were found to be closely related to the splitting of the ferromagnetic material into regions with different magnetic properties, in correlation with the complex morphology of the porous system. Independent magnetization reversal is detected for these regions, and is accompanied by its strong impact on the magnetic order in the capping IrMn layer. Electron-magnon scattering is found to be a dominant mechanism of magnetoresistance, determining its almost linear field dependence in a high magnetic field and contributing to its magnetoresistance behavior, similar to magnetization reversal, in a low magnetic field. Partial rotation of IrMn magnetic moments, consistent with the magnetization reversal of the ferromagnet, is proposed as an explanation for the two-state resistance behavior observed in switching between high-resistive and low-resistive values at the magnetization reversal of the porous system studied.

18.
PLoS Genet ; 13(8): e1006952, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28793313

RESUMO

Leprosy is a human infectious disease caused by Mycobacterium leprae. A strong host genetic contribution to leprosy susceptibility is well established. However, the modulation of the transcriptional response to infection and the mechanism(s) of disease control are poorly understood. To address this gap in knowledge of leprosy pathogenicity, we conducted a genome-wide search for expression quantitative trait loci (eQTL) that are associated with transcript variation before and after stimulation with M. leprae sonicate in whole blood cells. We show that M. leprae antigen stimulation mainly triggered the upregulation of immune related genes and that a substantial proportion of the differential gene expression is genetically controlled. Indeed, using stringent criteria, we identified 318 genes displaying cis-eQTL at an FDR of 0.01, including 66 genes displaying response-eQTL (reQTL), i.e. cis-eQTL that showed significant evidence for interaction with the M. leprae stimulus. Such reQTL correspond to regulatory variations that affect the interaction between human whole blood cells and M. leprae sonicate and, thus, likely between the human host and M. leprae bacilli. We found that reQTL were significantly enriched among binding sites of transcription factors that are activated in response to infection, and that they were enriched among single nucleotide polymorphisms (SNPs) associated with susceptibility to leprosy per se and Type-I Reaction, and seven of them have been targeted by recent positive selection. Our study suggested that natural selection shaped our genomic diversity to face pathogen exposure including M. leprae infection.


Assuntos
Antígenos de Bactérias/imunologia , Hanseníase/genética , Locos de Características Quantitativas , Regulação para Baixo , Estudos de Associação Genética , Predisposição Genética para Doença , Interações Hospedeiro-Patógeno/genética , Humanos , Hanseníase/imunologia , Mycobacterium leprae , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal , RNA Bacteriano/isolamento & purificação , Regulação para Cima
19.
PLoS Genet ; 13(2): e1006637, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28222097

RESUMO

Leprosy Type-1 Reactions (T1Rs) are pathological inflammatory responses that afflict a sub-group of leprosy patients and result in peripheral nerve damage. Here, we employed a family-based GWAS in 221 families with 229 T1R-affect offspring with stepwise replication to identify risk factors for T1R. We discovered, replicated and validated T1R-specific associations with SNPs located in chromosome region 10p21.2. Combined analysis across the three independent samples resulted in strong evidence of association of rs1875147 with T1R (p = 4.5x10-8; OR = 1.54, 95% CI = 1.32-1.80). The T1R-risk locus was restricted to a lncRNA-encoding genomic interval with rs1875147 being an eQTL for the lncRNA. Since a genetic overlap between leprosy and inflammatory bowel disease (IBD) has been detected, we evaluated if the shared genetic control could be traced to the T1R endophenotype. Employing the results of a recent IBD GWAS meta-analysis we found that 10.6% of IBD SNPs available in our dataset shared a common risk-allele with T1R (p = 2.4x10-4). This finding points to a substantial overlap in the genetic control of clinically diverse inflammatory disorders.


Assuntos
Predisposição Genética para Doença , Doenças Inflamatórias Intestinais/genética , Hanseníase/genética , RNA Longo não Codificante/genética , Feminino , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/patologia , Hanseníase/complicações , Hanseníase/patologia , Masculino , Degeneração Neural/complicações , Degeneração Neural/genética , Degeneração Neural/patologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , RNA Longo não Codificante/biossíntese , Fatores de Risco , Vietnã
20.
Int J Mol Sci ; 21(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32993038

RESUMO

Epithelial ovarian cancer (EOC) is the deadliest gynecological cancer, and the major cause of death is mainly attributed to metastasis. MicroRNAs (miRNAs) are a group of small non-coding RNAs that exert important regulatory functions in many biological processes through their effects on regulating gene expression. In most cases, miRNAs interact with the 3' UTRs of target mRNAs to induce their degradation and suppress their translation. Aberrant expression of miRNAs has been detected in EOC tumors and/or the biological fluids of EOC patients. Such dysregulation occurs as the result of alterations in DNA copy numbers, epigenetic regulation, and miRNA biogenesis. Many studies have demonstrated that miRNAs can promote or suppress events related to EOC metastasis, such as cell migration, invasion, epithelial-to-mesenchymal transition, and interaction with the tumor microenvironment. In this review, we provide a brief overview of miRNA biogenesis and highlight some key events and regulations related to EOC metastasis. We summarize current knowledge on how miRNAs are dysregulated, focusing on those that have been reported to regulate metastasis. Furthermore, we discuss the role of miRNAs in promoting and inhibiting EOC metastasis. Finally, we point out some limitations of current findings and suggest future research directions in the field.


Assuntos
Carcinoma Epitelial do Ovário , MicroRNAs/fisiologia , Neoplasias Ovarianas , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Movimento Celular , Epigênese Genética , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Neoplásica , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Microambiente Tumoral
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