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1.
Chemosphere ; 365: 143324, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39278327

RESUMO

This study utilized liquid chromatography (LC) alongside Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to explore the dyes and chemical contaminants in Loji River, Indonesia. We tentatively identified a total of 655 contaminants at various confidence level, subsequently classifying them into 22 distinct categories. Of the 54 dyes we detected, 12 corresponded with entries in our specialized in-house database. These 12 dyes were further confirmed by reference standards, matching both retention time (RT) and MS/MS spectra. LC-FT-ICR MS data showed that dyes from printing batik and textile industries are key contributors to river pollution. Particularly noteworthy were two sample locations that displayed substantial contamination, predominantly from azoic and reactive dyes. Additionally, pharmaceuticals were identified as one of the most frequently occurring contaminants, underscoring the inadequacies in the area's sewage management. To corroborate these findings, we conducted physicochemical, phytotoxicity, and acute toxicity tests, all of which verified the harmful effects of the Loji River's water on both the local flora and human populations. Notably, water samples that tested positive for dye contamination exhibited elevated toxicity levels. To the best of our knowledge, this study is pioneering in its molecular-level investigation of dye contamination in Southeast Asian rivers. Our results accentuate the pressing need for both targeted and non-targeted screening methods to identify contaminants in the surface waters of developing nations.

2.
Phytochem Anal ; 35(4): 799-816, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38297293

RESUMO

INTRODUCTION: Nymphaea rubra belongs to the Nymphaea family and is regarded as a vegetable used in traditional medicine to cure several ailments. These species are rich in phenolic acid, flavonoids, and hydrolysable tannin. OBJECTIVE: This study aimed to assess the biological activities of Nymphaea rubra flowers (NRF) and leaves (NRL) by identifying and quantifying their polyphenolic compounds using ultra-performance liquid chromatography coupled to quadrupole cyclic ion mobility time-of-flight mass spectrometry (UHPLC-Q-cIM-TOF-MS) and triple quadrupole mass spectrometry (UHPLC-TQ-MS). METHODOLOGY: NRF and NRL powder was extracted with methanol and fractionated using hexane, ethylacetate, and water. Antioxidant and α-glucosidase, and tyrosinase enzyme inhibitory activities were evaluated. The polyphenolic components of NRF and NRL were identified and quantified using UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS. The method was validated using linearity, precision, accuracy, limit of detection (LOD), and lower limit of quantification (LLOQ). RESULTS: Bioactive substances and antioxidants were highest in the ethylacetate fraction of flowers and leaves. Principal component analysis showed how solvent and plant components affect N. rubra's bioactivity and bioactive compound extraction. A total of 67 compounds were identified, and among them 21 significant polyphenols were quantified. Each calibration curve had R2 > 0.998. The LOD and LLOQ varied from 0.007 to 0.09 µg/mL and from 0.01 to 0.1 µg/mL, respectively. NRF contained a significant amount of gallic acid (10.1 mg/g), while NRL contained abundant pentagalloylglucose (2.8 mg/g). CONCLUSION: The developed method is simple, rapid, and selective for the identification and quantification of bioactive molecules. These findings provide a scientific basis for N. rubra's well-documented biological effects.


Assuntos
Antioxidantes , Flores , Nymphaea , Folhas de Planta , Polifenóis , Cromatografia Líquida de Alta Pressão/métodos , Folhas de Planta/química , Polifenóis/análise , Flores/química , Antioxidantes/análise , Antioxidantes/farmacologia , Nymphaea/química , Espectrometria de Massas/métodos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Reprodutibilidade dos Testes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/análise , alfa-Glucosidases/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/análise
3.
J Phys Condens Matter ; 35(42)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37369228

RESUMO

We report detailed magnetic and magnetotransport properties of single-crystalline GdAgSb2antiferromagnet. The electronic transport properties show metallic behavior along with large, anisotropic, and non-saturating magnetoresistance (MR) in transverse experimental configuration. At 2 K and 9 T, the value of MR reaches as high as ∼1.8×103%. The anisotropic MR along with additional features for applied magnetic field along some specific crystallographic directions reveal the quasi-two-dimensional nature of the Fermi surface of GdAgSb2. Hall resistivity confirms the presence of two types of charge carriers. The high carrier mobilities (∼1.2×104 cm2 V-1 s-1) and nearly-compensated electron and hole-density (∼1019 cm-3) could be responsible for the large transverse MR in GdAgSb2. We have also observed the de Haas-van Alphen oscillations in the magnetization measurements below 7 K. Furthermore, the robust planar Hall effect, which persists up to high temperatures, could indicate the nontrivial nature of the electronic band structure for GdAgSb2.

4.
Food Chem ; 404(Pt A): 134544, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36265274

RESUMO

Nymphaea rubra flowers (NRF) are widely used as a food and in folk medicine throughout the subtropical regions due to their health-promoting characteristics. This study characterized the phytochemical composition of various extracts/fractions of NRF by establishing a quadrupole-cyclic ion mobility-time-of-flight (Q-cIM-TOF) mass spectrometry method in both positive and negative electrospray ionization modes. Over 100 phytoconstituents were tentatively identified, among which 53 phytochemicals belonging to phenolic acids, tannins, flavonoids, terpenoids, alkaloids, xanthones, and naphthopyrones have never been documented in NRF before. Moreover, the ethyl acetate fraction of NRF demonstrated strong antioxidant potential (IC50: 9.21 ± 0.47 µg/mL in DPPH assay and 13.65 ± 0.03 µg/mL in ABTS assay) and tyrosinase, α-glucosidase, and elastase inhibition (IC50: 10.58 ± 0.20, 2.48 ± 0.02, and 38.15 ± 0.25 µg/mL, respectively). The findings highlight the value of NRF as a source of functional components and broaden its potential applications in the food and nutraceutical industries.


Assuntos
Nymphaea , Nymphaea/metabolismo , Extratos Vegetais/química , Compostos Fitoquímicos/análise , Antioxidantes/química , Flores/química , Flavonoides , Espectrometria de Massas
5.
Chemosphere ; 313: 137505, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36509189

RESUMO

No biodegradation methods are absolute in the treatment of all textile dyes, which leads to structure-dependent degradation. In this study, biodegradation of three azo dyes, reactive black 5 (RB5), acid blue 113 (AB113), and acid orange 7 (AO7), was investigated using an immobilized fungus, Trametes hirsuta D7. The degraded metabolites were identified using UPLC-PDA-FTICR MS and the biodegradation pathway followed was proposed. RB5 (92%) and AB113 (97%) were effectively degraded, whereas only 30% of AO7 was degraded. Molecular docking simulations were performed to determine the reason behind the poor degradation of AO7. Weak binding affinity, deficiency in H-bonding interactions, and the absence of interactions between the azo (-NN-) group and active residues of the model laccase enzyme were responsible for the low degradation efficiency of AO7. Furthermore, cytotoxicity and genotoxicity assays confirmed that the fungus-treated dye produced non-toxic metabolites. The observations of this study will be useful for understanding and further improving enzymatic dye biodegradation.


Assuntos
Compostos Azo , Trametes , Simulação de Acoplamento Molecular , Biodegradação Ambiental , Compostos Azo/toxicidade , Compostos Azo/metabolismo , Corantes/química , Lacase/química
6.
ACS Appl Mater Interfaces ; 14(45): 51105-51112, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36323003

RESUMO

The substrate plays a crucial role in determining the transport and low-frequency noise behavior of graphene field-effect devices. Typically, a heavily doped Si/SiO2 substrate is used to fabricate these devices for efficient gating. Trapping-detrapping processes close to the graphene/substrate interface are the dominant sources of resistance fluctuations in the graphene channel, while Coulomb fluctuations arising due to any remote charge fluctuations inside the bulk of the substrate are effectively screened by the heavily doped substrate. Here, we present the electronic transport and low-frequency noise characteristics of a large-area CVD graphene field-effect transistor (FET) prepared on a lightly doped Si/SiO2 substrate (NA ≈ 1015 cm-3). Through a systematic characterization of transport, noise, and capacitance at various temperatures, we reveal that the remote Si/SiO2 interface can affect the charge transport in graphene severely and any charge fluctuations inside the bulk of the silicon substrate can be sensed by the graphene channel. The resistance (R) vs back-gate voltage (Vbg) characteristics of the device show a hump around the depletion region formed at the SiO2/Si interface, confirmed by the capacitance (C)-voltage (V) measurement. A low-frequency noise measurement on these fabricated devices shows a peak in the noise amplitude close to the depletion region. This indicates that due to the absence of any charge layer at the Si/SiO2 interface, the screening ability decreases, and as a consequence, any fluctuations in the deep-level Coulomb impurities inside the silicon substrate can be observed as noise in resistance in the graphene channel via mobility fluctuations. The noise behavior on ionic liquid-gated graphene on the same substrate exhibits no such peak in noise and can be explained by the interfacial trapping-detrapping processes close to the graphene channel. Our study will definitely be useful for integrating graphene with the existing silicon technology, in particular, for high-frequency applications.

7.
Food Chem ; 373(Pt B): 131541, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34810014

RESUMO

In this study, the effectiveness of powder laser desorption/ionization (LDI) coupled with Fourier-transform ion cyclotron mass spectrometry (FT-ICR MS) was evaluated for the improved coverage of plant metabolites. Ground plant (powder) was fixed on a metal plate using double-sided tape. Compared with the conventional approach involving liquid extraction, which is followed by electrospray ionization MS analysis, a smaller amount of sample (∼200 µg) was required in the proposed method. Additionally, the laborious steps of liquid extraction, concentration, and solid-phase extraction were avoided. Employing the proposed method in Centella asiatica leaves analysis, higher number of reproducible molecular formulas (>5000) and metabolites (>650) were obtained than the conventional methods. Flavonoids, phenolic acids, xanthones, lipids, carbohydrates, terpenoids, and alkaloids compounds were detected from leaves, stems, and roots of C. asiatica. This study indicates that LDI FT-ICR MS is a quick and effective tool for enhanced plant metabolite profiling in the solid phase.


Assuntos
Ciclotrons , Lasers , Análise de Fourier , Espectrometria de Massas , Pós , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
Case Rep Infect Dis ; 2021: 6436936, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868691

RESUMO

BACKGROUND: Although the prevalence of HIV is low in Bangladesh, there is a potential for an increased number of cases. This is because of high cross-border mobility (India and Myanmar) of people and increased injection drug abusers amongst youth in the cities and rural areas, HIV can present in many ways, from asymptomatic to advanced disease, including various atypical (generalized itching) and advanced (loss of vision) manifestations. A high degree of suspicion is required to diagnose HIV in a country like Bangladesh. Early diagnosis and prompt treatment are essential to have a better outcome. METHODS: Here, we report two thought-provoking cases where patients were suffering from generalized itchy lesions (pruritic papular eruption) throughout the body for a long time and gradual loss of vision in another case. RESULTS: Due to lack of suspicion, initially, HIV screening was not done. Both patients visited several health centres, but no diagnosis was made. Moreover, COVID-19 pandemic worsens the situation. Finally, they were diagnosed with HIV; unfortunately, one of them lost her vision due to CMV retinitis and another patient died of other complications. CONCLUSION: Ongoing COVID-19 pandemic put many challenges to ensure optimum care, especially for patients with long-sufferings like HIV. Clinicians have to have a very high degree of suspicion while dealing with patients presented with rare manifestations, particularly in a low endemic clinical setting.

9.
Saudi J Biol Sci ; 28(12): 6721-6729, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34866971

RESUMO

Glucocorticoids (GCs) initiate oxidative stress and cause renal damage which lead to hypertension, heart failure and ultimately death. The current study aimed to investigate the alterations in serum biochemical parameters i.e. HDL and LDL; gross anatomy, histomorphology and histomorphometry of broiler kidney in response to dietary GC, dexamethasone (DEX). Day old chicks (DOCs) were randomly assigned into four groups: control and three treatment groups (T1, T2 and T3). The control group was fed commercial broiler type ration and the treated groups were fed commercial broiler type ration containing GC (Dexamethasone @ 3, 5 and 7 mg/kg in T1, T2 and T3 group respectively). To measure the biochemical parameters, blood samples were collected on days 7, 14, 21, and 28 of the experiment. For histological investigation, kidney (left) samples were collected from the individual birds after sacrificing on days 7, 14, 21, and 28 of the experiment. Histomorphological alterations of the kidney were assessed by routine hematoxylin and eosin (H&E) staining. Biochemical analysis showed significantly increased serum HDL and LDL level compared to the control. In gross study, dark congested kidney was found with significantly decreased weight, length and width. Treatment with DEX augmented congestion, inflammation and fibrosis in kidney, as evidence by histomorphometric study. Extensively degenerated and atrophied glomeruli, degenerated tubular epithelium with distorted tubules and inter tubular empty spaces were seen. Percentage of atrophied glomeruli increased significantly and maximum percentage of glomerular atrophy was seen at day 28. These changes were found more explicitly in the higher dose group. Histomorphometric study also revealed significant decrease in the diameter of glomerulus. The findings of this study suggest that DEX may alter the serum biochemical parameters as well as kidney gross and histomorphology.

10.
J Hazard Mater ; 405: 124176, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33131941

RESUMO

Biodegradation and metabolic pathways of three anthraquinone dyes, Reactive Blue 4 (RB4), Remazol Brilliant Blue - R (RBBR), and Acid Blue 129 (AB129) by Trametes hirsuta D7 fungus immobilized in light expanded clay aggregate (LECA) were investigated. Morphological characteristics observed with scanning electron microscope (SEM) showed successful immobilization of the fungus in LECA. Based on UV absorbance measurement, immobilized T. hirsuta D7 effectively degraded 90%, 95%, and 96% of RB4, RBBR and AB129, respectively. Metabolites were identified with high-resolution mass spectrometry (HRMS) and degradation pathway of the dyes by T. hirsuta D7 was proposed. Toxicity assay on human dermal fibroblast (HDF) showed that anthraquinone dyes exhibits significant toxicity of 35%, 40%, and 34% reduction of cell viability by RB4, RBBR, and AB129, respectively. Fungal treatment resulted in an abatement of the toxicity and cell viability was increased up to 94%. The data clearly showed the effectiveness of immobilized T. hirsuta D7 in LECA on detoxification of anthraquinone dyes. This study provides potential and fundamental understanding of wastewater treatment using the newly isolated fungus T. hirsuta D7.


Assuntos
Antraquinonas , Trametes , Antraquinonas/toxicidade , Biodegradação Ambiental , Argila , Corantes/toxicidade , Humanos , Lacase , Redes e Vias Metabólicas , Polyporaceae
11.
PLoS One ; 8(9): e75697, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086616

RESUMO

Tendon injuries are a common age-related degenerative condition where current treatment strategies fail to restore functionality and normal quality of life. This disease also occurs naturally in horses, with many similarities to human tendinopathy making it an ideal large animal model for human disease. Regenerative approaches are increasingly used to improve outcome involving mesenchymal stem cells (MSCs), supported by clinical data where injection of autologous bone marrow derived MSCs (BM-MSCs) suspended in marrow supernatant into injured tendons has halved the re-injury rate in racehorses. We hypothesized that stem cell therapy induces a matrix more closely resembling normal tendon than the fibrous scar tissue formed by natural repair. Twelve horses with career-ending naturally-occurring superficial digital flexor tendon injury were allocated randomly to treatment and control groups. 1X10(7) autologous BM-MSCs suspended in 2 ml of marrow supernatant were implanted into the damaged tendon of the treated group. The control group received the same volume of saline. Following a 6 month exercise programme horses were euthanized and tendons assessed for structural stiffness by non-destructive mechanical testing and for morphological and molecular composition. BM-MSC treated tendons exhibited statistically significant improvements in key parameters compared to saline-injected control tendons towards that of normal tendons and those in the contralateral limbs. Specifically, treated tendons had lower structural stiffness (p<0.05) although no significant difference in calculated modulus of elasticity, lower (improved) histological scoring of organisation (p<0.003) and crimp pattern (p<0.05), lower cellularity (p<0.007), DNA content (p<0.05), vascularity (p<0.03), water content (p<0.05), GAG content (p<0.05), and MMP-13 activity (p<0.02). Treatment with autologous MSCs in marrow supernatant therefore provides significant benefits compared to untreated tendon repair in enhancing normalisation of biomechanical, morphological, and compositional parameters. These data in natural disease, with no adverse findings, support the use of this treatment for human tendon injuries.


Assuntos
Medula Óssea/fisiologia , Doenças dos Cavalos/terapia , Células-Tronco Mesenquimais/fisiologia , Tendinopatia/fisiopatologia , Tendinopatia/terapia , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Doenças dos Cavalos/fisiopatologia , Cavalos , Condicionamento Físico Animal/fisiologia , Tendinopatia/veterinária , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/terapia , Traumatismos dos Tendões/veterinária , Tendões/fisiologia , Cicatrização/fisiologia
12.
Int J Neurosci ; 117(2): 187-201, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17365107

RESUMO

This article investigates the effects of ethanol on Insulin-like growth factor (IGF)-I secretion, p42/44 mitogen-activated protein kinase (MAPK) activity, and IGF binding protein (IGFBP-1 secretion) in primary cultured rat hepatocytes. The p42/44 MAPK activity increased with the ethanol concentration compared to control after ethanol treatment. The secretion of IGF-I significantly increased compared to control, but IGFBP-1 secretion was inhibited. Treatment with 4-methylpyrazole blocked the IGF-I and IGFBP-1 secretion and p42/44 MAPK activity. Increased IGF-I secretion and inhibited IGFBP-1 secretion due to ethanol-induced p42/44 MAPK activity (at 30 min) was blocked by treatment with PD98059. Taken together, these results suggest that ethanol is involved in the modulation of the secretion of IGF-I and IGFBP-1 by p42/44 MAPK in primary cultured rat hepatocytes. In addition, inhibition of p42/44 MAPK activity by ethanol occurs via the activity of ADH.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Hepatócitos/efeitos dos fármacos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Álcool Desidrogenase/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Hepatócitos/metabolismo , Masculino , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/fisiologia , Radioimunoensaio/métodos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
J Vet Med Sci ; 67(7): 723-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16082123

RESUMO

Two Holstein Friesian calves were referred to the Animal Medical Center of Chonbuk National University with severe lameness on the hind limb(s), flexed stifle joint and an inability to walk since birth. Based on the clinical history, clinical findings and radiography of the stifle joint, the cases were diagnosed as grade III lateral patellar luxation (LPL). Trochleoplasty along with medial retinacular reinforcement and lateral release were performed in both calves. The calves recovered 3 to 4 weeks after surgery. Trochleoplasty along with medial retinacular reinforcement and lateral release can be an effective technique for the treatment of LPL in calves.


Assuntos
Doenças dos Bovinos/cirurgia , Fêmur/cirurgia , Coxeadura Animal/cirurgia , Luxação Patelar/veterinária , Joelho de Quadrúpedes/cirurgia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Fêmur/anormalidades , Luxação Patelar/cirurgia , Radiografia
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