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1.
Proc Natl Acad Sci U S A ; 121(19): e2321992121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38684000

RESUMO

Tertiary chirality describes the handedness of supramolecular assemblies and relies not only on the primary and secondary structures of the building blocks but also on topological driving forces that have been sparsely characterized. Helical biopolymers, especially DNA, have been extensively investigated as they possess intrinsic chirality that determines the optical, mechanical, and physical properties of the ensuing material. Here, we employ the DNA tensegrity triangle as a model system to locate the tipping points in chirality inversion at the tertiary level by X-ray diffraction. We engineer tensegrity triangle crystals with incremental rotational steps between immobile junctions from 3 to 28 base pairs (bp). We construct a mathematical model that accurately predicts and explains the molecular configurations in both this work and previous studies. Our design framework is extendable to other supramolecular assemblies of helical biopolymers and can be used in the design of chiral nanomaterials, optically active molecules, and mesoporous frameworks, all of which are of interest to physical, biological, and chemical nanoscience.


Assuntos
DNA , Biopolímeros/química , DNA/química , Difração de Raios X , Conformação de Ácido Nucleico , Modelos Moleculares , Estereoisomerismo
2.
Blood ; 141(25): 3109-3121, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947859

RESUMO

Inhibitors of complement and coagulation are present in the saliva of a variety of blood-feeding arthropods that transmit parasitic and viral pathogens. Here, we describe the structure and mechanism of action of the sand fly salivary protein lufaxin, which inhibits the formation of the central alternative C3 convertase (C3bBb) and inhibits coagulation factor Xa (fXa). Surface plasmon resonance experiments show that lufaxin stabilizes the binding of serine protease factor B (FB) to C3b but does not detectably bind either C3b or FB alone. The crystal structure of the inhibitor reveals a novel all ß-sheet fold containing 2 domains. A structure of the lufaxin-C3bB complex obtained via cryo-electron microscopy (EM) shows that lufaxin binds via its N-terminal domain at an interface containing elements of both C3b and FB. By occupying this spot, the inhibitor locks FB into a closed conformation in which proteolytic activation of FB by FD cannot occur. C3bB-bound lufaxin binds fXa at a separate site in its C-terminal domain. In the cryo-EM structure of a C3bB-lufaxin-fXa complex, the inhibitor binds to both targets simultaneously, and lufaxin inhibits fXa through substrate-like binding of a C-terminal peptide at the active site as well as other interactions in this region. Lufaxin inhibits complement activation in ex vivo models of atypical hemolytic uremic syndrome (aHUS) and paroxysmal nocturnal hemoglobinuria (PNH) as well as thrombin generation in plasma, providing a rationale for the development of a bispecific inhibitor to treat complement-related diseases in which thrombosis is a prominent manifestation.


Assuntos
Coagulação Sanguínea , Fator B do Complemento , Microscopia Crioeletrônica , Fator B do Complemento/química , Fator B do Complemento/metabolismo , Ativação do Complemento , Serina Endopeptidases , Complemento C3b/química
3.
Nano Lett ; 24(12): 3557-3565, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38499397

RESUMO

Magnetic skyrmions are topological spin textures which are envisioned as nanometer scale information carriers in magnetic memory and logic devices. The recent demonstrations of room temperature skyrmions and their current induced manipulation in ultrathin films were first steps toward the realization of such devices. However, important challenges remain regarding the electrical detection and the low-power nucleation of skyrmions, which are required for the read and write operations. Here, we demonstrate, using operando magnetic microscopy experiments, the electrical detection of a single magnetic skyrmion in a magnetic tunnel junction (MTJ) and its nucleation and annihilation by gate voltage via voltage control of magnetic anisotropy. The nucleated skyrmion can be manipulated by both gate voltages and external magnetic fields, leading to tunable intermediate resistance states. Our results unambiguously demonstrate the readout and voltage controlled write operations in a single MTJ device, which is a major milestone for low power skyrmion based technologies.

4.
Neurobiol Dis ; 198: 106552, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844244

RESUMO

Multiple sclerosis (MS) is an autoimmune and neurodegenerative disease leading to demyelination and axonal loss. Current treatments are immunomodulatory or immunosuppressive drugs acting on the inflammatory component. However, these treatments do not adequately address the crucial aspect of neuroprotection. Recently, an association between an altered balance of adipokines and MS has been proposed as both a risk factor for developing MS and a chronic disease aggravating factor. Specifically, a decrease of apelin plasma levels in MS patients compared to controls correlates with the number of relapses and disease severity. Here we report a dramatic downregulation of apelin levels in the CNS of EAE mice which is also detected in MS patients brain samples compared to controls. Exploiting innovative design and synthesis techniques, we engineered a novel fluorinated apelin-13 peptide characterized by enhanced plasmatic stability compared to its native counterpart. With this peptide, we assessed the potential therapeutic benefits of apelin preventive supplementation in the EAE mouse model. We show that the fluorinated Apelin-13 peptide ameliorates EAE clinical score and preserves myelin content in the EAE MOG model recapitulating the progressive form of disease. These results combined with ex-vivo experiments in brain organotypic slices and in vitro studies in neurons and primary microglia and macrophages suggest that apelin has neuroprotective effects and influences the microglia/macrophages function.


Assuntos
Encefalomielite Autoimune Experimental , Camundongos Endogâmicos C57BL , Esclerose Múltipla , Fármacos Neuroprotetores , Animais , Fármacos Neuroprotetores/farmacologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Camundongos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Modelos Animais de Doenças , Microglia/efeitos dos fármacos , Microglia/metabolismo , Apelina/metabolismo , Apelina/farmacologia
5.
J Transl Med ; 22(1): 498, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796431

RESUMO

OBJECTIVE: The aim of the present pilot study was to assess the effectiveness of the platelet-rich fibrin (PRF) apical barrier for the placement of MTA for the treatment of teeth with periapical lesions and open apices. METHODS: A total of thirty teeth on twenty-eight patients with open apices and periapical periodontitis were enrolled and divided into two groups in the present pilot study. In the PRF group (fourteen teeth in thirteen patients), nonsurgical endodontic treatment was performed using PRF as an apical matrix, after which the apical plug of the MTA was created. For the non-PRF group (fourteen teeth in fourteen patients), nonsurgical endodontic therapy was performed using only the MTA for an apical plug with no further periapical intervention. Clinical findings and periapical digital radiographs were used for evaluating the healing progress after periodic follow-ups of 1, 3, 6, and 9 months. The horizontal dimension of the periapical lesion was gauged, and the changes in the dimensions were recorded each time. The Friedman test, Dunn-Bonferroni post hoc correction, and Mann-Whitney U test were used for statistical analysis, with P < 0.05 serving as the threshold for determining statistical significance. RESULTS: All patients in both groups in the present pilot study had no clinical symptoms after 1 month, with a significant reduction in the periapical lesion after periodic appointments. The lesion width of the PRF group was significantly smaller than that of the non-PRF group in the sixth and ninth month after treatment. CONCLUSIONS: PRF is a promising apical barrier matrix when combined with MTA for the treatment of teeth with open apices and periapical periodontitis. Small number of study subjects and the short time of follow-up period limit the generalizability of these results. TRIAL REGISTRATION: TCTR, TCTR20221109006. Registered 09 November 2022 - Retrospectively registered, https://www.thaiclinicaltrials.org/show/TCTR20221109006 .


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Fibrina Rica em Plaquetas , Silicatos , Ápice Dentário , Humanos , Projetos Piloto , Fibrina Rica em Plaquetas/metabolismo , Feminino , Masculino , Compostos de Alumínio/uso terapêutico , Silicatos/uso terapêutico , Compostos de Cálcio/uso terapêutico , Adulto , Ápice Dentário/patologia , Ápice Dentário/diagnóstico por imagem , Combinação de Medicamentos , Pessoa de Meia-Idade , Óxidos/uso terapêutico , Periodontite Periapical/terapia , Periodontite Periapical/diagnóstico por imagem
6.
Opt Lett ; 49(1): 137-140, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134171

RESUMO

Micro-joule UV-range (350-415 nm) femtosecond-laser pulses generated via frequency-doubled parametric conversion of 525-nm 150-fs pulses of Yb-glass laser were used for "hot" photoluminescence excitation in a diamond plate enriched by blue-emitting N3-centers (zero-phonon line, ZPL, at 415 nm). Photoluminescence spectra acquired in the range of 400-500 nm exhibited wavelength-independent well-resolved ZPL and phonon progression bands, where the involved phonons possessed the only energies of 0.09 eV (LA-phonons) and 0.15 eV (softened LO/TO-phonons), potentially, as a result of a Clemens decay mechanism. Photoluminescence yield in the ZPL and other phonon bands exhibited the power slope of 1.8 at lower energies and ≈1 at higher energies. The transition zone at fluence ∼1014-15 photons/cm2 was related to the saturation of the pumped resonance transition and the slower non-radiative vibrational relaxation to the ZPL-related excited electronic state and the nanosecond spontaneous photoluminescence transition to the ground state. As a result, the absorption cross section σ(370-390 nm) ≈1·10-15 cm2 and concentration [N3] ≈6·1014 cm-3 were determined along with the ZPL absorption cross section σ(415 nm) ≈2.5·10-15 cm2, and the non-radiative vibrational relaxation rate was estimated, providing altogether the crucial information on lasing possibilities in N3-doped diamonds.

7.
BMC Cancer ; 24(1): 176, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317094

RESUMO

BACKGROUND: This study aimed to evaluate the efficacy and side effects of first-line afatinib treatment in a real-world setting in Vietnam. METHODS: This retrospective study was conducted across nine hospitals in Vietnam. Advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients who received afatinib as first-line therapy between April 2018 and June 2022 were included, and patient medical records were reviewed. Key outcomes were overall response rate (ORR), time-to-treatment failure (TTF), and tolerability. RESULTS: A total of 343 patients on first-line afatinib were eligible for the study. EGFR exon 19 deletion (Del19) alone was detected in 46.9% of patients, L858R mutation alone in 26.3%, and other uncommon EGFR mutations, including compound mutations, in 26.8%. Patients with brain metastases at baseline were 25.4%. Patients who received 40 mg, 30 mg, and 20 mg as starting doses of afatinib were 58.6%, 39.9%, and 1.5%, respectively. The ORR was 78.1% in the overall population, 82.6% in the Del19 mutation subgroup, 73.3% in the L858R mutation subgroup, and 75.0% in the uncommon mutation subgroup (p > 0.05). The univariate and multivariate analyses indicate that the ORR increased when the starting dose was 40 mg compared to starting doses below 40 mg (83.9% vs. 74.3%, p = 0.034). The median TTF (mTTF) was 16.7 months (CI 95%: 14.8-18.5) in all patients, with a median follow-up time of 26.2 months. The mTTF was longer in patients in the common EGFR mutation subgroup (Del19/L858R) than in those in the uncommon mutation subgroup (17.5 vs. 13.8 months, p = 0.045) and in those without versus with brain metastases at baseline (17.5 vs. 15.1 months, p = 0.049). There were no significant differences in the mTTF between subgroups based on the starting dose of 40 mg and < 40 mg (16.7 vs. 16.9 months, p > 0.05). The most common treatment-related adverse events (any grade/grade ≥ 3) were diarrhea (55.4%/3.5%), rash (51.9%/3.2%), paronychia (35.3%/5.0%), and stomatitis (22.2%/1.2%). CONCLUSIONS: Afatinib demonstrated clinical effectiveness and good tolerability in Vietnamese EGFR-mutant NSCLC patients. In our real-world setting, administering a starting dose below 40 mg might result in a reduction in ORR; however, it might not have a significant impact on TTF.


Assuntos
Afatinib , Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Afatinib/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Coortes , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Vietnã/epidemiologia
8.
Langmuir ; 40(11): 6051-6064, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38437236

RESUMO

Preconcentration of biomolecules based on ion concentration polarization (ICP) has been splendidly applied to various biomedical and chemical processes. However, in many circumstances, biomolecule preconcentration could not occur due to the lack of full studies on the preconcentration mechanism, especially on the effect of microchannel dimensions. In this work, we provide analytical studies on the critical dimensions (minimum and maximum) of microchannels for the preconcentration of biomolecules. These formulas are verified with the numerical results by fully solving the coupled governing equations: Poisson-Nernst-Planck and Navier-Stokes experiments with appropriate boundary conditions and assumptions. In addition, we examine the impact of operational parameters, such as electric potentials and critical external pressures, on the formation of the preconcentration. Moreover, two important results are provided for the first time, including the position of the preconcentrated biomolecule region and the concentration enhancement factor of the biomolecules. These analytical and numerical results are consistent with experimental observations and, therefore, could provide sharp insight into the mechanism of biomolecule preconcentration and give useful guidelines to better design and optimize ICP-based microfluidic preconcentration devices.


Assuntos
Dispositivos Lab-On-A-Chip
9.
Analyst ; 149(8): 2252-2271, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38470814

RESUMO

A convergent sector in microfluidic devices utilizing ion concentration polarization (ICP) can help increase the preconcentration rate and the concentration enhancement factor (CEF) of biomolecules. In this work, we present a detailed study of the nozzle-like-squeeze effect of a convergent channel on the preconcentration of biomolecules. By numerically solving coupled Nernst-Planck-Poisson-Navier-Stokes governing equations for the 2D channel model, we report the first study on the critical width of a convergent region in the channel to retain the advantage of the nozzle-like-squeeze effect in speeding up preconcentration and augmenting CEF. In addition, we investigated the impact of the location and the dimensions of a convergent sector on the mechanism of biomolecule preconcentration. The location of an ion-selective membrane was also determined to ensure that biomolecules are focused on the convergent region of the channel. Moreover, we introduce analytical studies to compare and verify simulation findings. Specifically, the formulas for the critical dimensions of a convergent channel, location of a preconcentrated biomolecule plug, and position of an ion-selective membrane are presented. Furthermore, important working parameters, including electric potentials and hydrostatic pressures, were examined to scrutinize their effect on convergent concentrators. These detailed analytical solutions and numerical simulation results are consistent with experimental observations, providing deep insights into the ICP phenomenon and the preconcentration mechanism of biomolecules in convergent microfluidic concentration devices.


Assuntos
Técnicas Analíticas Microfluídicas , Técnicas Analíticas Microfluídicas/métodos , Dispositivos Lab-On-A-Chip
10.
Org Biomol Chem ; 22(11): 2307-2312, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38410077

RESUMO

Phytic acid is abundant in various plant-based foods and is considered agricultural waste. Here, we demonstrate the effectiveness of this organophosphorus acid as a sustainable catalyst for the direct amination reactions of allylic alcohols. This approach is successfully performed in air using technical grade solvents, affording allylanilines in moderate to excellent yields. Challenging electron-rich anilines react effectively, and their corresponding Friedel-Crafts side products can be minimised under the optimised reaction conditions. A variety of asymmetrically substituted allylic alcohols are tolerated, while the scope is extended to amide, and C-, O- and S-nucleophiles.

11.
BMC Infect Dis ; 24(1): 622, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38910264

RESUMO

BACKGROUND: Respiratory infections have long been recognized as a primary cause of acute exacerbation of chronic obstructive pulmonary disease (AE-COPD). Additionally, the emergence of antimicrobial resistance has led to an urgent and critical situation in developing countries, including Vietnam. This study aimed to investigate the distribution and antimicrobial resistance of bacteria in patients with AE-COPD using both conventional culture and multiplex real-time PCR. Additionally, associations between clinical characteristics and indicators of pneumonia in these patients were examined. METHODS: This cross-sectional prospective study included 92 AE-COPD patients with pneumonia and 46 without pneumonia. Sputum specimens were cultured and examined for bacterial identification, and antimicrobial susceptibility was determined for each isolate. Multiplex real-time PCR was also performed to detect ten bacteria and seven viruses. RESULTS: The detection rates of pathogens in AE-COPD patients with pneumonia were 92.39%, compared to 86.96% in those without pneumonia. A total of 26 pathogenic species were identified, showing no significant difference in distribution between the two groups. The predominant bacteria included Klebsiella pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae, followed by Acinetobacter baumannii and Streptococcus mitis. There was a slight difference in antibiotic resistance between bacteria isolated from two groups. The frequency of H. influenzae was notably greater in AE-COPD patients who experienced respiratory failure (21.92%) than in those who did not (9.23%). S. pneumoniae was more common in patients with stage I (44.44%) or IV (36.36%) COPD than in patients with stage II (17.39%) or III (9.72%) disease. ROC curve analysis revealed that C-reactive protein (CRP) levels could distinguish patients with AE-COPD with and without pneumonia (AUC = 0.78). CONCLUSION: Gram-negative bacteria still play a key role in the etiology of AE-COPD patients, regardless of the presence of pneumonia. This study provides updated evidence for the epidemiology of AE-COPD pathogens and the appropriate selection of antimicrobial agents in Vietnam.


Assuntos
Antibacterianos , Bactérias , Farmacorresistência Bacteriana , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/microbiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Estudos Transversais , Vietnã/epidemiologia , Estudos Prospectivos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/genética , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/epidemiologia , Testes de Sensibilidade Microbiana , Escarro/microbiologia , Idoso de 80 Anos ou mais , Pneumonia/microbiologia , Pneumonia/tratamento farmacológico , Pneumonia/epidemiologia
12.
J Fluoresc ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280054

RESUMO

SiO2@Ag nanocomposite (NC) has been synthesized by the chemical reduction and StÓ§ber method for Metal-enhanced fluorescence (MEF) of Rhodmine 6G (R6G) and Surface-enhanced Raman spectroscopy (SERS) of Malachite green (MG). As-synthesized SiO2@Ag NC indicated SiO2 nanosphere (NS) and Ag nanoparticle (NP) morphologies. The SiO2@Ag NC was high quality with a well-defined crystallite phase with average sizes of 24 nm and 132 nm for Ag NP and SiO2 NC, respectively. By using SiO2@Ag NC, the photoluminescence (PL) intensity of the R6G (at 59.17 ppm) was increased approximately 133 times. The SERS of the MG (at 1.0 ppm) with SiO2@Ag NC as substrate clearly observed vibrational modes in MG dye at 798, 916, 1172, 1394, and 1616 cm-1. As a result, the SERS enhancement factor (EFSERS) at 1172 cm-1 obtained 6.3 × 106. This initial study points to the potential of SiO2@Ag NC as a promising material for MEF and SERS substrates to detect dyes at low concentrations.

13.
Appl Microbiol Biotechnol ; 108(1): 107, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38217253

RESUMO

Streptomyces peucetius ATCC 27952 is known to produce a variety of secondary metabolites, including two important antitumor anthracyclines: daunorubicin and doxorubicin. Identification of peucemycin and 25-hydroxy peucemycin (peucemycin A), as well as their biosynthetic pathway, has expanded its biosynthetic potential. In this study, we isolated a new peucemycin derivative and identified it as 19-hydroxy peucemycin (peucemycin B). Its antibacterial activity was lower than those of peucemycin and peucemycin A. On the other hand, this newly identified peucemycin derivative had higher anticancer activity than the other two compounds for MKN45, NCI-H1650, and MDA-MB-231 cancer cell lines with IC50 values of 76.97 µM, 99.68 µM, and 135.2 µM, respectively. Peucemycin biosynthetic gene cluster revealed the presence of a SARP regulator named PeuR whose role was unknown. The presence of the TTA codon in the peuR and the absence of global regulator BldA in S. peucetius reduced its ability to regulate the peucemycin biosynthetic gene cluster. Hence, different mutants harboring these genes were prepared. S. peucetius bldA25 harboring bldA produced 1.75 times and 1.77 times more peucemycin A (11.8 mg/L) and peucemycin B (21.2 mg/L), respectively, than the wild type. On the other hand, S. peucetius R25 harboring peuR produced 1.86 and 1.79 times more peucemycin A (12.5 mg/L) and peucemycin B (21.5 mg/L), respectively, than the wild type. Finally, strain S. peucetius bldAR25 carrying bldA and peuR produced roughly 3.52 and 2.63 times more peucemycin A (23.8 mg/L) and peucemycin B (31.5 mg/L), respectively, than the wild type. KEY POINTS: • This study identifies a new peucemycin derivative, 19-hydroxy peucemycin (peucemycin B). • The SARP regulator (PeuR) acts as a positive regulator of the peucemycin biosynthetic gene cluster. • The overexpression of peuR and heterologous expression of bldA increase the production of peucemycin derivatives.


Assuntos
Daunorrubicina , Doxorrubicina , Streptomyces , Antraciclinas/metabolismo , Antibióticos Antineoplásicos/farmacologia
14.
Sensors (Basel) ; 24(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38257521

RESUMO

The rapid evolution of 3D technology in recent years has brought about significant change in the field of agriculture, including precision livestock management. From 3D geometry information, the weight and characteristics of body parts of Korean cattle can be analyzed to improve cow growth. In this paper, a system of cameras is built to synchronously capture 3D data and then reconstruct a 3D mesh representation. In general, to reconstruct non-rigid objects, a system of cameras is synchronized and calibrated, and then the data of each camera are transformed to global coordinates. However, when reconstructing cattle in a real environment, difficulties including fences and the vibration of cameras can lead to the failure of the process of reconstruction. A new scheme is proposed that automatically removes environmental fences and noise. An optimization method is proposed that interweaves camera pose updates, and the distances between the camera pose and the initial camera position are added as part of the objective function. The difference between the camera's point clouds to the mesh output is reduced from 7.5 mm to 5.5 mm. The experimental results showed that our scheme can automatically generate a high-quality mesh in a real environment. This scheme provides data that can be used for other research on Korean cattle.

15.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869195

RESUMO

One new bithiophene derivative, 5-(but-3-en-1-yn-1-yl)-5'-(methoxymethyl)-2,2'-bithiophene (1), along with twelve known compounds, senecioester (2), tiglinsaureester (3), 5-acetoxymethyl-2'-(but-3-en-1-yn-1-yl)-2,5'-bithiophene (4), 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5), 5-hydroxymethyl-(2,5':2',5'')-terthienyl tiglate (6), 5-hydroxymethyl-(2,5':2',5'')-terthienyl agelate (7), 5- hydroxymethyl-2,5':2',5''-terthiophene dimethylacrylate (8), 5-methoxymethyl-2,2':5',2''-terthiophene (9), α-terthiophene (10), 1,3,8,9-tetrahydroxycoumestan 3-sulfate (11), demethylwedelolactone (12), and wedelolactone (13) were isolated from the methanol extract of aerial parts of Eclipta prostrata (L.) L. All isolated compounds were evaluated for the protective ability on the HepG2 cells. At the concentration of 100 µM, compounds 11-13 showed the highest hepatoprotective effects, with HepG2 cell viability ranging from 38.68% to 48.54%. Bithiophenes showed higher hepatoprotective cell viability than terthiophenes.

16.
Molecules ; 29(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38611738

RESUMO

The Streptomyces strain G222, isolated from a Vietnamese marine sediment, was confidently identified by 16S rRNA gene sequencing. Its AcOEt crude extract was successfully analyzed using non-targeted LC-MS/MS analysis, and molecular networking, leading to a putative annotation of its chemical diversity thanks to spectral libraries from GNPS and in silico metabolite structure prediction obtained from SIRIUS combined with the bioinformatics tool conCISE (Consensus Annotation Propagation of in silico Elucidations). This dereplication strategy allowed the identification of an interesting cluster of a series of putative cyclic and linear lipopeptides of the lichenysin and surfactin families. Lichenysins (3-7) were isolated from the sub-fraction, which showed significant anti-biofilm activity against Pseudomonas aeruginosa MUC-N1. Their structures were confirmed by detailed 1D and 2D NMR spectroscopy (COSY, HSQC, HMBC, TOCSY, ROESY) recorded in CD3OH, and their absolute configurations were determined using the modified Marfey's method. The isolated lichenysins showed anti-biofilm activity at a minimum concentration of 100 µM. When evaluated for antibacterial activity against a panel of Gram-positive and Gram-negative strains, two isolated lichenysins exhibited selective activity against the MRSA strain without affecting its growth curve and without membranotropic activity. This study highlights the power of the MS/MS spectral similarity strategy using computational methods to obtain a cross-validation of the annotated molecules from the complex metabolic profile of a marine sediment-derived Streptomyces extract. This work provides the first report from a Streptomyces strain of combined cyclic and linear lichenysins and surfactins, known to be characteristic compounds of the genus Bacillus.


Assuntos
Sedimentos Geológicos , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida , RNA Ribossômico 16S , Vietnã
17.
BMC Oral Health ; 24(1): 230, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350906

RESUMO

BACKGROUND: The present study aimed to evaluate the effectiveness of using platelet-rich fibrin (PRF) as the apical matrix for the placement of MTA in nonsurgical endodontic therapy for teeth with periapical lesions and open apices. METHODS: Twelve teeth from eleven patients with periapical periodontitis and open apices were enrolled in the study. Nonsurgical endodontic therapy was performed with the PRF used as an apical barrier and the MTA manipulated as an apical plug for further thermoplasticized gutta percha in the remaining part of the root canal. Clinical signs and periapical digital radiographs were recorded and analyzed to evaluate the curing progress after periodical follow-ups of 1, 3, and 6 months. The horizontal dimension of the periapical lesion was determined, and the changes in the dimensions were recorded each time. The Friedman test was used for statistical analysis, with P < .05 serving as the threshold for determining statistical significance. RESULTS: All patients had no clinical symptoms after the first month of treatment, with a significant reduction in the periapical lesion after periodical appointments. CONCLUSIONS: PRF is an effective barrier when combined with MTA for the treatment of teeth with periapical periodontitis and open apices.


Assuntos
Periodontite Periapical , Fibrina Rica em Plaquetas , Materiais Restauradores do Canal Radicular , Humanos , Compostos de Cálcio/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Guta-Percha/uso terapêutico , Periodontite Periapical/terapia , Periodontite Periapical/patologia , Combinação de Medicamentos , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/patologia , Óxidos/uso terapêutico , Silicatos/uso terapêutico
18.
Bratisl Lek Listy ; 125(6): 392-398, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757598

RESUMO

OBJECTIVES: This study aims to determine the malnutrition status among Vietnamese patients newly diagnosed with gastric cancer (GC). BACKGROUND: GC remains the top rank of common and deadly diseases. With limited clinical manifestation, most GC patients were diagnosed at late stages when tumor is not radically resected. Malnutrition was associated with poor prognosis of GC, such as prolonged hospitalization, limited treatment efficacy and low survival rate. METHODS: The cross-sectional descriptive study recruited 77 patients newly diagnosed with GC and 90 healthy individuals (HC). The data used for this study were approved by the local Ethical Committee. The data were analysed on STATA 14.0 and GraphPad Prism 8.0. RESULTS: We observed the male dominant distribution in GC cohort and over 65% of GC were firstly diagnosed at advanced stages (III and IV). Anemia was detected in about 50% of GC patients. Hyponutrition was prevalent in newly diagnosed GC. We found the decreased tendency of anemia related indexes from HC to early stages (I and II) and advanced stages (III and IV) of GC patients. CONCLUSION: Anemia and hypoproteinemia occurred frequently among Vietnamese newly diagnosed GC. The nutrition therapy would benefit GC patients (Tab. 4, Fig. 4, Ref. 20).


Assuntos
Anemia , Desnutrição , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Vietnã/epidemiologia , Anemia/diagnóstico , Anemia/etiologia , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Idoso , Adulto , Estadiamento de Neoplasias
19.
Cancer Invest ; : 1-17, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36719061

RESUMO

The SPOT-MAS assay "Screening for the Presence Of Tumor by Methylation And Size" detects the five most common cancers in Vietnam by evaluating circulating tumor DNA in the blood. Here, we validated its performance in a prospective multi-center clinical trial, K-DETEK. Our analysis of 2795 participants from 14 sites across Vietnam demonstrates its ability to detect cancers in asymptomatic individuals with a positive predictive value of 60%, with 83.3% accuracy in detecting tumor location. We present a case report to support further using SPOT-MAS as a complementary method to achieve early cancer detection and provide the opportunity for early treatment.

20.
Circ Res ; 128(1): 42-58, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33135960

RESUMO

RATIONALE: The recent discovery of meningeal lymphatics in mammals is reshaping our understanding of fluid homeostasis and cellular waste management in the brain, but visualization and experimental analysis of these vessels is challenging in mammals. Although the optical clarity and experimental advantages of zebrafish have made this an essential model organism for studying lymphatic development, the existence of meningeal lymphatics has not yet been reported in this species. OBJECTIVE: Examine the intracranial space of larval, juvenile, and adult zebrafish to determine whether and where intracranial lymphatic vessels are present. METHODS AND RESULTS: Using high-resolution optical imaging of the meninges in living animals, we show that zebrafish possess a meningeal lymphatic network comparable to that found in mammals. We confirm that this network is separate from the blood vascular network and that it drains interstitial fluid from the brain. We document the developmental origins and growth of these vessels into a distinct network separated from the external lymphatics. Finally, we show that these vessels contain immune cells and perform live imaging of immune cell trafficking and transmigration in meningeal lymphatics. CONCLUSIONS: This discovery establishes the zebrafish as a important new model for experimental analysis of meningeal lymphatic development and opens up new avenues for probing meningeal lymphatic function in health and disease.


Assuntos
Linfangiogênese , Vasos Linfáticos/fisiologia , Meninges/fisiologia , Microscopia Confocal , Imagem Óptica , Animais , Animais Geneticamente Modificados , Linfangiogênese/efeitos dos fármacos , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/imunologia , Meninges/imunologia , Infiltração de Neutrófilos , Neutrófilos/imunologia , Fator C de Crescimento do Endotélio Vascular/farmacologia , Peixe-Zebra/genética
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