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1.
Int J Mol Sci ; 25(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39125721

RESUMO

Para-hydroxycinnamic acid (pHCA) is one of the most abundant naturally occurring hydroxycinnamic acids, a class of chemistries known for their antioxidant properties. In this study, we evaluated the impact of pHCA on different parameters of skin aging in in vitro skin models after H2O2 and UV exposure. These parameters include keratinocyte senescence and differentiation, inflammation, and energy metabolism, as well as the underlying molecular mechanisms. Here we demonstrate that pHCA prevents oxidative stress-induced premature senescence of human primary keratinocytes in both 2D and 3D skin models, while improving clonogenicity in 2D. As aging is linked to inflammation, referred to as inflammaging, we analyzed the release of IL-6, IL-8, and PGE2, known to be associated with senescence. All of them were downregulated by pHCA in both normal and oxidative stress conditions. Mechanistically, DNA damage induced by oxidative stress is prevented by pHCA, while pHCA also exerts a positive effect on the mitochondrial and glycolytic functions under stress. Altogether, these results highlight the protective effects of pHCA against inflammaging, and importantly, help to elucidate its potential mechanisms of action.


Assuntos
Senescência Celular , Ácidos Cumáricos , Queratinócitos , Estresse Oxidativo , Envelhecimento da Pele , Pele , Humanos , Ácidos Cumáricos/farmacologia , Senescência Celular/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Inflamação/metabolismo , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Raios Ultravioleta/efeitos adversos , Antioxidantes/farmacologia , Células Cultivadas , Interleucina-8/metabolismo , Interleucina-6/metabolismo
2.
Med Mol Morphol ; 57(3): 233-243, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38904830

RESUMO

Hepatobiliary mucoepidermoid carcinoma is a rare malignant tumor comprising mucous, intermediate, and epidermoid cells. Herein, we presented a case of primary liver mucoepidermoid carcinoma preoperatively misdiagnosed as conventional intrahepatic cholangiocarcinoma. A 67-year-old male was admitted to our hospital. Preoperative laboratory tests showed increased aspartate transaminase, alanine transaminase, and carbohydrate antigen 19-9. Abdominal Computer Tomography revealed a 4.8 × 4.9 cm liver mass in segment VI. A preliminary diagnosis of intrahepatic cholangiocarcinoma was made, with undergoing partial hepatectomy. However, on histopathology, the tumor comprised a mixture of epidermoid, mucous, and intermediate cells with diffuse infiltrating at the tumor margin. On special stains, mucous and intermedia cells were positive for mucicarmine and Alcian blue, whereas epidermoid cells were positive for Keratin 5/6 and p63. Intermediate cells are also positive for p63. All tumor cells were positive for Keratin 7. The Ki-67 index was 35%. The final diagnosis was primary hepatic mucoepidermoid carcinoma. Although rare, hepatic mucoepidermoid carcinoma should be considered in the intrahepatic cholangiocarcinoma differential diagnosis. We reviewed previous studies and found that hepatobiliary mucoepidermoid carcinoma is more likely to originate from the biliary tract adjacent to the tumor.


Assuntos
Carcinoma Mucoepidermoide , Neoplasias Hepáticas , Humanos , Masculino , Carcinoma Mucoepidermoide/patologia , Carcinoma Mucoepidermoide/diagnóstico , Carcinoma Mucoepidermoide/cirurgia , Carcinoma Mucoepidermoide/diagnóstico por imagem , Idoso , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Colangiocarcinoma/patologia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Diagnóstico Diferencial , Tomografia Computadorizada por Raios X
3.
Med Mol Morphol ; 57(3): 200-217, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38960952

RESUMO

Intrahepatic cholangiocarcinoma (iCCA) exhibits different blood imaging features and prognosis depending on histology. To clarity histopathological growth patterns (HGPs) and vascularization processes of iCCA, we collected 145 surgical specimens and histologically classified them into large bile duct (LBD) (20 cases), small bile duct (SBD) (54), cholangiolocarcinoma (CLC) (35), combined SBD-CLC (cSBD-CLC) (26), and ductal plate malformation (DPM) (10) (sub)types. According to the invasive pattern at the interface between tumor and adjacent background liver, HGPs were classified into desmoplastic, pushing, and replacing HGPs. Desmoplastic HGP predominated in LBD type (55.5%), while replacing HGP was common in CLC (82.9%) and cSBD-CLC (84.6%) subtypes. Desmoplastic HGP reflected angiogenesis, while replacing HGP showed vessel co-option in addition to angiogenesis. By evaluating microvessel density (MVD) using vascular markers, ELTD1 identified vessel co-option and angiogenesis, and ELTD1-positive MVD at invasive margin in replacing HGP was significantly higher than those in desmoplastic and pushing HGPs. REDD1, an angiogenesis-related marker, demonstrated preferably higher MVD in the tumor center than in other areas. iCCA (sub)types and HGPs were closely related to vessel co-option and immune-related factors (lymphatic vessels, lymphocytes, and neutrophils). In conclusion, HGPs and vascular mechanisms characterize iCCA (sub)types and vessel co-option linked to the immune microenvironment.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neovascularização Patológica , Colangiocarcinoma/patologia , Colangiocarcinoma/irrigação sanguínea , Humanos , Neoplasias dos Ductos Biliares/patologia , Masculino , Feminino , Neovascularização Patológica/patologia , Pessoa de Meia-Idade , Idoso , Adulto , Densidade Microvascular
4.
Pak J Pharm Sci ; 37(1(Special)): 223-229, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38747273

RESUMO

In this study, the anti-osteogenic properties of the volatile oil extracted from Homalomena gigantea rhizome using ethyl acetate (EtOAc) and methanol (MeOH) were examined. Gas chromatography-mass spectrometry (GC-MS) was employed for the identification of volatile components. Following this, bioassays were performed to evaluate their effects on osteogenesis, encompassing parameters like cell viability, osteoblast differentiation, collagen synthesis and mineralization. The GC-MS analysis revealed 19 compounds in the EtOAc extract and 36 compounds in the MeOH extract. In the MeOH extract, major constituents included bis(2-ethylhexyl) terephthalate (13.83%), linalool (9.58%), palmitic acid (6.55%) and stearic acid (4.29%). The EtOAc extract contained bis(2-ethylhexyl) terephthalate (16.64%), palmitic acid (5.60%) and stearic acid (3.11%) as the predominant components. Both the EtOAc and MeOH extracts of H. gigantea exhibited promising potential for further investigation in anti-osteoporosis research. These findings contribute to the exploration of natural compounds with potential anti-osteoporotic properties, expanding our understanding of their therapeutic potential.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis , Osteogênese , Extratos Vegetais , Rizoma , Osteogênese/efeitos dos fármacos , Rizoma/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Animais , Sobrevivência Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Camundongos , Ácido Palmítico/farmacologia , Monoterpenos Acíclicos/farmacologia
5.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903586

RESUMO

A novel aptamer-based fluorescent-sensing platform with a triple-helix molecular switch (THMS) was proposed as a switch for detecting the arsenic(III) ion. The triple helix structure was prepared by binding a signal transduction probe and arsenic aptamer. Additionally, the signal transduction probe labeled with fluorophore (FAM) and quencher (BHQ1) was employed as a signal indicator. The proposed aptasensor is rapid, simple and sensitive, with a limit of detection of 69.95 nM. The decrease in peak fluorescence intensity shows a linear dependence, with the concentration of As(III) in the range of 0.1 µM to 2.5 µM. The whole detection process takes 30 min. Moreover, the THMS-based aptasensor was also successfully used to detect As(III) in a real sample of Huangpu River water with good recoveries. The aptamer-based THMS also presents distinct advantages in stability and selectivity. The proposed strategy developed herein can be extensively applied in the field of food inspection.


Assuntos
Aptâmeros de Nucleotídeos , Arsênio , Técnicas Biossensoriais , Limite de Detecção , Corantes Fluorescentes/química , Aptâmeros de Nucleotídeos/química
6.
J Am Chem Soc ; 144(26): 11580-11593, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35729768

RESUMO

Peptide-derived cyclophanes inhabit a unique niche in the chemical space of macrocyclic peptides with several examples of pharmaceutical importance. Although both synthetic and biocatalytic methods are available for constructing these macrocycles, versatile (bio)catalysts able to incorporate a variety of amino acids that compose the macrocycle would be useful for the creation of diverse peptide cyclophanes. In this report, we synergized the use of bioinformatic tools to map the biosynthetic landscape of radical SAM enzymes (3-CyFEs) that catalyze three-residue cyclophane formation in the biosynthesis of a new family of RiPP natural products, the triceptides. This analysis revealed 3940 (3113 unique) putative precursor sequences predicted to be modified by 3-CyFEs. Several uncharacterized maturase systems were identified that encode unique precursor types. Functional studies were carried out in vivo in Escherichia coli to identify modified precursors containing His and Tyr residues. NMR analysis of the products revealed that Tyr and His can also be incorporated into cyclophane macrocycles by 3-CyFEs. Collectively, all aromatic amino acids can be incorporated by 3-CyFEs, and the cyclophane formation strictly occurs via a C(sp2)-C(sp3) cross-link between the (hetero)aromatic ring to Cß. In addition to 3-CyFEs, we functionally validated an Fe(II)/α-ketoglutarate-dependent hydroxylase, resulting in ß-hydroxylated residues within the cyclophane rings. This study reveals the potential breadth of triceptide precursors and a systematic approach for studying these enzymes to broaden the diversity of peptide macrocycles.


Assuntos
Biologia Computacional , Peptídeos , Catálise , Biologia Computacional/métodos , Escherichia coli/metabolismo , Peptídeos/química
7.
Am J Med Genet A ; 188(7): 2048-2060, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35365919

RESUMO

Developmental and epileptic encephalopathies (DEE) refers to a group of rare and severe neurodevelopmental disorders where genetic etiologies can play a major role. This study aimed to elucidate the genetic etiologies of a cohort of 53 Vietnamese patients with DEE. All patients were classified into known electroclinical syndromes where possible. Exome sequencing (ES) followed by a targeted analysis on 294 DEE-related genes was then performed. Patients with identified causative variants were followed for 6 months to determine the impact of genetic testing on their treatment. The diagnostic yield was 38.0% (20/53), which was significantly higher in the earlier onset group (<12 months) than in the later onset group (≥12 months). The 19 identified variants belonged to 11 genes with various cellular functions. Genes encoding ion channels especially sodium voltage-gated channel were the most frequently involved. Most variants were missense variants and located in key protein functional domains. Four variants were novel and four had been reported previously but in different phenotypes. Within 6 months of further follow-up, treatment changes were applied for six patients based on the identified disease-causing variants, with five patients showing a positive impact. This is the first study in Vietnam to analyze the genetics of DEE. This study confirms the strong involvement of genetic etiologies in DEE, especially early onset DEE. The study also contributes to clarify the genotype-phenotype correlations of DEE and highlights the efficacy of targeted ES in the diagnosis and treatment of DEE.


Assuntos
Encefalopatias , Exoma , Povo Asiático , Encefalopatias/genética , Exoma/genética , Testes Genéticos , Humanos , Mutação , Fenótipo , Vietnã
8.
Nucleic Acids Res ; 48(18): 10567-10575, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32960213

RESUMO

Beyond the consensus definition of G-quadruplex-forming motifs with tracts of continuous guanines, G-quadruplexes harboring bulges in the G-tetrad core are prevalent in the human genome. Here, we study the incorporation of a duplex hairpin within a bulge of a G-quadruplex. The NMR solution structure of a G-quadruplex containing a duplex bulge was resolved, revealing the structural details of the junction between the duplex bulge and the G-quadruplex. Unexpectedly, instead of an orthogonal connection the duplex stem was observed to stack below the G-quadruplex forming a unique quadruplex-duplex junction. Breaking up of the immediate base pair step at the junction, coupled with a narrowing of the duplex groove within the context of the bulge, led to a progressive transition between the quadruplex and duplex segments. This study revealed that a duplex bulge can be formed at various positions of a G-quadruplex scaffold. In contrast to a non-structured bulge, the stability of a G-quadruplex slightly increases with an increase in the duplex bulge size. A G-quadruplex structure containing a duplex bulge of up to 33 nt in size was shown to form, which was much larger than the previously reported 7-nt bulge. With G-quadruplexes containing duplex bulges representing new structural motifs with potential biological significance, our findings would broaden the definition of potential G-quadruplex-forming sequences.


Assuntos
DNA/ultraestrutura , Quadruplex G , Guanina/química , Conformação de Ácido Nucleico , Pareamento de Bases , Sequência de Bases , Dicroísmo Circular , DNA/genética , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares
9.
J Am Pharm Assoc (2003) ; 62(4): 1197-1205.e4, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35151581

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) vaccine acceptance is essential in controlling the virus. Vaccine knowledge influences vaccine acceptance and understanding this is vital in planning immunization strategies. OBJECTIVES: This study aimed to examine the public COVID-19 vaccine knowledge levels and predictors of low knowledge levels in Vietnam. METHODS: A cross-sectional, community-based survey was conducted between April 16 and July 16, 2021. To examine the community knowledge levels regarding the vaccine essentialness and efficacy, a self-administered questionnaire was developed and comprised 7 questions with 5 Likert scale responses corresponding to the levels of agreement or disagreement with the provided statements and scores ranging from 0 to 4. An individual's knowledge score above the mean score of all participants was defined as "acceptable" and that below was defined as "low." RESULTS: Among 1708 respondents, the mean age was 34.3 ± 13.4 years, 942 (55.2%) were females, and 797 (46.7%) had acceptable knowledge levels. Age (adjusted odds ratio [AOR] 0.984 [95% CI 0.972-0.995], P = 0.005) and being vaccinated against COVID-19 (0.653 [0.431-0.991], P = 0.045) were inversely associated with lower knowledge levels. Those with a Gapminder income of $8 to < $15 per day (1.613 [1.117-2.329], P = 0.001), $2 to < $8 (2.093 [1.313-3.335], P = 0.002), and < $2 (3.341 [1.951-5.722], P < 0.001), less than a high school education (4.214 [1.616-10.988], P = 0.003), and nonclinical professionals and nonhealth lecturers (1.83 [1.146-2.922], P = 0.01) were positively associated with lower knowledge levels. CONCLUSION: To ensure a successful vaccine rollout, it is crucial to improve community knowledge about vaccine essentialness and efficacy. Those who are at young age, who have low income or education levels, and working in nonclinical and nonhealth education fields should be the target of the intervention programs. Community education programs may benefit from using those who have been immunized as role models.


Assuntos
COVID-19 , Vacinas , Adulto , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Vacinação , Vietnã , Adulto Jovem
10.
Bioorg Med Chem Lett ; 43: 128054, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33895275

RESUMO

A convenient microwave-assisted one-pot four-component synthetic approach was developed en route to novel functionalized benzo[a]pyridazino[3,4-c]phenazine derivatives starting from 2-hydroxy-1,4-naphthoquinone, aromatic aldehydes, methyl hydrazine and o-phenylenediamine. Nine new derivatives were successfully synthesized and subsequently evaluated in terms of their biological profiles. The results revealed good cytotoxic activities of compounds 6a, 6h against KB, HepG2, Lu1 and MCF7 human cancer cell lines. Besides that, compound 6d exhibited promising antimicrobial activities toward Staphylococcuc aureus and Bacillus subtilis bacterial strains with IC50 < 6 µM.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Fenazinas/farmacologia , Piridazinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenazinas/síntese química , Fenazinas/química , Piridazinas/síntese química , Piridazinas/química , Relação Estrutura-Atividade
11.
Bioorg Med Chem Lett ; 37: 127841, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33556568

RESUMO

A series of novel podophyllotoxin-naphthoquinone compounds 5a-p were synthesized in good yields using microwave-assisted four-component reactions of 2-hydroxy-1,4-naphthoquinone, aromatic benzaldehydes, tetronic acid and ammonium acetate. All the synthesized compounds were fully characterized by spectral data and evaluated for their cytotoxicity activities against KB, HepG2, Lu1, MCF7, and non-cancerous Hek-293 cell lines. Among 16 new compounds screened, compounds 5a, 5d, 5h, and 5k displayed high potent inhibitory activities with IC50 < 40 nM against HepG2 and SK-Lu-1 cell lines, and showed lower toxicity for non-cancerous Hek-293 cell line, demonstrating the potential importance of these compounds in the development of potential anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Micro-Ondas , Naftoquinonas/farmacologia , Podofilotoxina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Naftoquinonas/síntese química , Naftoquinonas/química , Podofilotoxina/síntese química , Podofilotoxina/química , Relação Estrutura-Atividade
12.
Environ Sci Technol ; 54(4): 2448-2458, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31790213

RESUMO

Despite recent evidence from full-scale plants suggesting that Candidatus Accumulibacter may be capable of using amino acids, this metabolic trait has never been confirmed in a bioreactor experiment. Here we show that an enriched culture of Ca. Accumulibacter clade IIF strain SCELSE-1 could metabolize 11 of 20 α-amino acids, with aspartate, glutamate, asparagine, and glutamine resulting in the highest phosphorus removal. The anaerobic uptake of aspartate and glutamate was achieved through a glutamate/aspartate-proton symporter fully powered by the proton motive force (PMF). Under anaerobic conditions aspartate was deaminized and routed into core carbon metabolic pathways to form polyhydroxyalkanoates (PHA). The lack of genes encoding NADH dependent isocitrate dehydrogenase in the Ca. Accumulibacter genome resulted in a kinetic barrier for glutamate to be channelled to the TCA cycle. Glutamate was stored as glutamate polymer. When amino acids (aspartate or glutamate) and acetate were supplied together, Ca. Accumulibacter took up both carbon sources simultaneously, with the uptake rate of each carbon source largely preserved. Overall energy savings (up to 17%) were achieved under mixed carbon scenarios, due to the ability of Ca. Accumulibacter to rearrange its anaerobic carbon metabolism based on the reducing power, PMF and ATP balance.


Assuntos
Carbono , Fósforo , Aminoácidos , Anaerobiose , Reatores Biológicos
13.
Environ Sci Technol ; 53(14): 8157-8166, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31184114

RESUMO

A single Nitrospira sublineage I OTU was found to perform nitrite oxidation in full-scale domestic wastewater treatment plants (WWTPs) in the tropics. This taxon had an apparent oxygen affinity constant lower than that of the full-scale domestic activated sludge cohabitating ammonium oxidizing bacteria (AOB) (0.09 ± 0.02 g O2 m-3 versus 0.3 ± 0.03 g O2 m-3). Thus, nitrite oxidizing bacteria (NOB) may in fact thrive under conditions of low oxygen supply. Low dissolved oxygen (DO) conditions selected for and high aeration inhibited the NOB in a long-term lab-scale reactor. The relative abundance of Nitrospira sublineage I gradually decreased with increasing DO until it was washed out. Nitritation was sustained even after the DO was lowered subsequently. The morphologies of AOB and NOB microcolonies responded to DO levels in accordance with their oxygen affinities. NOB formed densely packed spherical clusters with a low surface area-to-volume ratio compared to the Nitrosomonas-like AOB clusters, which maintained a porous and nonspherical morphology. In conclusion, the effect of oxygen on AOB/NOB population dynamics depends on which OTU predominates given that oxygen affinities are species-specific, and this should be elucidated when devising operating strategies to achieve mainstream partial nitritation.


Assuntos
Oxigênio , Esgotos , Amônia , Bactérias , Reatores Biológicos , Nitritos , Oxirredução
14.
BMC Infect Dis ; 18(1): 112, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29510687

RESUMO

BACKGROUND: Drug resistant tuberculosis (TB) is increasing in prevalence worldwide. Treatment failure and relapse is known to be high for patients with isoniazid resistant TB treated with standard first line regimens. However, risk factors for unfavourable outcomes and the optimal treatment regimen for isoniazid resistant TB are unknown. This cohort study was conducted when Vietnam used the eight month first line treatment regimen and examined risk factors for failure/relapse among patients with isoniazid resistant TB. METHODS: Between December 2008 and June 2011 2090 consecutive HIV-negative adults (≥18 years of age) with new smear positive pulmonary TB presenting at participating district TB units in Ho Chi Minh City were recruited. Participants with isoniazid resistant TB identified by Microscopic Observation Drug Susceptibility (MODS) had extended follow-up for 2 years with mycobacterial culture to test for relapse. MGIT drug susceptibility testing confirmed 239 participants with isoniazid resistant, rifampicin susceptible TB. Bacterial and demographic factors were analysed for association with treatment failure and relapse. RESULTS: Using only routine programmatic sputum smear microscopy for assessment, (months 2, 5 and 8) 30/239 (12.6%) had an unfavourable outcome by WHO criteria. Thirty-nine patients were additionally detected with unfavourable outcomes during 2 year follow up, giving a total of 69/239 (28.9%) of isoniazid (INH) resistant cases with unfavourable outcome by 2 years of follow-up. Beijing lineage was the only factor significantly associated with unfavourable outcome among INH-resistant TB cases during 2 years of follow-up. (adjusted OR = 3.16 [1.54-6.47], P = 0.002). CONCLUSION: One third of isoniazid resistant TB cases suffered failure/relapse within 2 years under the old eight month regimen. Over half of these cases were not identified by standard WHO recommended treatment monitoring. Intensified research on early identification and optimal regimens for isoniazid resistant TB is needed. Infection with Beijing genotype of TB is a significant risk factor for bacterial persistence on treatment resulting in failure/relapse within 2 years. The underlying mechanism of increased tolerance for standard drug regimens in Beijing genotype strains remains unknown.


Assuntos
Antituberculosos/uso terapêutico , Isoniazida/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Recidiva , Rifampina/uso terapêutico , Fatores de Risco , Escarro/microbiologia , Falha de Tratamento , Vietnã , Adulto Jovem
15.
Mol Pharm ; 12(1): 223-31, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25423614

RESUMO

Novel roughness-controlled mannitol/LB Agar microparticles were synthesized by polymorphic transformation and self-assembly method using hexane as the polymorphic transformation reagent and spray-dried mannitol/LB Agar microparticles as the starting material. As-prepared microparticles were characterized by Fourier transform infrared spectra (FTIR), X-ray diffraction spectra (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and Andersen Cascade Impactor (ACI). The XRD and DSC results indicate that after immersing spray-dried mannitol/LB Agar microparticles in hexane, ß-mannitol was completely transformed to α-mannitol in 1 h, and all the δ-mannitol was transformed to α form after 14 days. SEM shows that during the transformation the nanobelts on the spray-dried mannitol/LB Agar microparticles become more dispersed and the contour of the individual nanobelts becomes more noticeable. Afterward, the nanobelts self-assemble to nanorods and result in rod-covered mannitol/LB Agar microparticles. FTIR indicates new hydrogen bonds were formed among mannitol, LB Agar, and hexane. SEM images coupled with image analysis software reveal that different surface morphology of the microparticles have different drug adhesion mechanisms. Comparison of ACI results and image analysis of SEM images shows that an increase in the particle surface roughness can increase the fine particle fractions (FPFs) using the rod-covered mannitol microparticles as drug carriers. Transformed microparticles show higher FPFs than commercially available lactose carriers. An FPF of 28.6 ± 2.4% was achieved by microparticles transformed from spray-dried microparticles using 2% mannitol(w/v)/LB Agar as feed solution. It is comparable to the highest FPF reported in the literature using lactose and spray-dried mannitol as carriers.


Assuntos
Ágar/química , Sistemas de Liberação de Medicamentos , Pulmão/efeitos dos fármacos , Manitol/química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Portadores de Fármacos/química , Ligação de Hidrogênio , Lactose/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Pós , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Termogravimetria , Difração de Raios X
16.
BMC Infect Dis ; 15: 70, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25888462

RESUMO

BACKGROUND: The GeneXpertMTB/RIF (Xpert) assay is now recommended by WHO for diagnosis of tuberculosis (TB) in children but evaluation data is limited. METHODS: One hundred and fifty consecutive HIV negative children (<15 years of age) presenting with suspected TB were enrolled at a TB referral hospital in Ho Chi Minh City, Vietnam. 302 samples including sputum (n = 79), gastric fluid (n = 215), CSF (n = 3), pleural fluid (n = 4) and cervical lymphadenopathic pus (n = 1) were tested by smear, automated liquid culture (Bactec MGIT) and Xpert. Patients were classified retrospectively using the standardised case definition into confirmed, probable, possible, TB unlikely or not TB categories. Test accuracy was evaluated against 2 gold standards: [1] clinical (confirmed, probable and possible TB) and [2] 'confirmed TB' alone. RESULTS: The median age of participants was 18 months [IQR 5-170]. When test results were aggregated by patient, the sensitivity of smear, Xpert and MGIT against clinical diagnosis as the gold standard were 9.2% (n = 12/131) [95%CI 4.2; 14.1], 20.6% (n = 27/131) [95%CI 13.7; 27.5] and 29.0% (n = 38/131) [21.2;36.8], respectively. Specificity 100% (n = 19/19), 94.7% (n = 18/19), 94.7% (n = 18/19), respectively. Xpert was more sensitive than smear (P = <0.001) and less sensitive than MGIT (P = 0.002). CONCLUSIONS: The systematic use of Xpert will increase early TB case confirmation in children and represents a major advance but sensitivity of all tests remains unacceptably low. Improved rapid diagnostic tests and algorithm approaches for pediatric TB are still an urgent research priority.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/diagnóstico , Adolescente , Algoritmos , Criança , Pré-Escolar , DNA Bacteriano/análise , Feminino , Infecções por HIV/diagnóstico , Humanos , Lactente , Masculino , Mycobacterium tuberculosis/genética , Estudos Prospectivos , Sensibilidade e Especificidade , Escarro/microbiologia , Vietnã
17.
J Am Chem Soc ; 136(52): 17969-73, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25459367

RESUMO

We report here the formation of stable DNA quadruplex-duplex hybrid complexes harboring multiple duplex stems within the same loop of a quadruplex structure. The folding topology of a two-stem quadruplex-duplex hybrid construct was validated using nuclear magnetic resonance (NMR) spectroscopy. This multi-stem incorporation principle is applicable at different loop positions of the same quadruplex construct and could be extended to three or more duplex stems, giving rise to a diverse range of possible structures. These multi-stem complexes offer new design principles for the assembly of DNA architectures. The potential existence of such complex motifs in genomic sequences could have biological implications and would represent novel targets for drug development.


Assuntos
DNA/química , Quadruplex G , Sequência de Bases , DNA/genética , Modelos Moleculares , Temperatura
18.
J Clin Microbiol ; 52(1): 226-33, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24197880

RESUMO

Tuberculous meningitis (TBM) is the most severe form of tuberculosis. Microbiological confirmation is rare, and treatment is often delayed, increasing mortality and morbidity. The GeneXpert MTB/RIF test was evaluated in a large cohort of patients with suspected tuberculous meningitis. Three hundred seventy-nine patients presenting with suspected tuberculous meningitis to the Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam, between 17 April 2011 and 31 December 2012 were included in the study. Cerebrospinal fluid samples were tested by Ziehl-Neelsen smear, mycobacterial growth indicator tube (MGIT) culture, and Xpert MTB/RIF. Rifampin (RIF) resistance results by Xpert were confirmed by an MTBDR-Plus line probe assay and all positive cultures were tested by phenotypic MGIT drug susceptibility testing. Overall, 182/379 included patients (48.0%) were diagnosed with tuberculous meningitis. Sensitivities of Xpert, smear, and MGIT culture among patients diagnosed with TBM were 59.3% (108/182 [95% confidence interval {CI}, 51.8 to 66.5%]), 78.6% (143/182 [95% CI, 71.9 to 84.3%]) and 66.5% (121/182 [95% CI, 59.1 to 73.3%]), respectively. There was one false-positive Xpert MTB/RIF test (99.5% specificity). Four cases of RIF resistance (4/109; 3.7%) were identified by Xpert, of which 3 were confirmed to be multidrug-resistant (MDR) TBM and one was culture negative. Xpert MTB/RIF is a rapid and specific test for the diagnosis of tuberculous meningitis. The addition of a vortexing step to sample processing increased sensitivity for confirmed TBM by 20% (P = 0.04). Meticulous examination of a smear from a large volume of cerebrospinal fluid (CSF) remains the most sensitive technique but is not practical in most laboratories. The Xpert MTB/RIF represents a significant advance in the early diagnosis of this devastating condition.


Assuntos
Antituberculosos/farmacologia , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/farmacologia , Tuberculose Meníngea/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido Cefalorraquidiano/microbiologia , Reações Falso-Positivas , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade , Vietnã , Adulto Jovem
19.
ACS Chem Biol ; 19(4): 855-860, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38452396

RESUMO

Triceptides are cyclophane-containing ribosomally synthesized and post-translationally modified peptides. The characteristic cross-links are formed between an aromatic ring to Cß on three-residue Ω1X2X3 motifs (Ω1 = aromatic). Here, we explored the promiscuity of the XYE family triceptide maturase, XncB from Xenorhabdus nematophila DSM 3370. Single amino acid variants were coexpressed with XncB in vivo in Escherichia coli, and we show that a variety of amino acids can be incorporated into the Phe-Gly-Asn cyclophane. Aromatic amino acids at the X3 position were accepted by the enzyme but yielded hydroxylated, rather than the typical cyclophane, products. These studies show that oxygen can be inserted but diverges in the final product formed relative to daropeptide maturases. Finally, truncations of the leader peptide showed that it is necessary for complete modification by XncB.


Assuntos
Aminoácidos , Peptídeos , Xenorhabdus , Aminoácidos/metabolismo , Peptídeos/química , Sinais Direcionadores de Proteínas , Xenorhabdus/química , Xenorhabdus/enzimologia , Xenorhabdus/genética , Xenorhabdus/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Especificidade por Substrato
20.
Heliyon ; 10(9): e30884, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774091

RESUMO

The demand for dietary fiber-rich cookies has increased due to customer awareness about the importance of dietary fiber in human health. In addition, the urge of creating food sustainability has led to the need to reuse food by-products. In this study, dietary fiber-rich cookies were developed by incorporating jackfruit rind (JFR) powder, a by-product of jackfruit processing, as a replacement for wheat flour. The study aimed to evaluate the effects of different replacement levels (0, 10, 20, 30 and 40 %) on the proximate composition, physical properties and overall sensory acceptability of the cookies. While JFR powder addition led to a significant increase in dietary fiber and antioxidant (phenolics, flavonoids and carotenoids) contents of the cookies, the physical properties and overall acceptability of the cookies were adversely affected. The total dietary fiber and total phenolic content of the cookies at 40 % JFR powder addition were 5 and 5.5 times as much as those of the cookies with 0 % JFR powder addition. To address the adverse effects of JFR addition, various concentrations of ascorbic acid (AA), a dough improver agent, were added to the blended dough, and their effects on dough and cookie properties were investigated. With the addition of ascorbic acid at concentrations of 200 mg ascorbic acid per 100 g of the blend flour, the cookie density and cookie hardness reduced by 16 % and 31 %, respectively while the overall acceptability increased by 37 % compared to those of the cookies without ascorbic acid addition.

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