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1.
Artigo em Inglês | MEDLINE | ID: mdl-34633180

RESUMO

Formic acid (HCOOH) is an important intermediate in chemical synthesis, pharmaceuticals, the food industry, and leather tanning and is considered to be an effective hydrogen storage molecule. Direct contact with its vapor and its inhalation lead to burns, nerve injury, and dermatosis. Thus, it is critical to establish efficient sensing materials and devices for the rapid detection of HCOOH. In the present study, we introduce a chemical sensor based on a quartz crystal microbalance (QCM) sensor capable of detecting trace amounts of HCOOH. This sensor is composed of colloidal phenyl-terminated carbon nitride (Ph-g-C3N4) quantum nanoflakes prepared using a facile solid-state method involving the supramolecular preorganization technology. In contrast to other synthetic methods of modified carbon nitride materials, this approach requires no hard templates, hazardous chemicals, or hydrothermal treatments. Comprehensive characterization and density functional theory (DFT) calculations revealed that the QCM sensor designed and prepared here exhibits enhanced detection sensitivity and selectivity for volatile HCOOH, which originates from chemical and hydrogen-bonding interactions between HCOOH and the surface of Ph-g-C3N4. According to DFT results, HCOOH is located close to the cavity of the Ph-g-C3N4 unit, with bonding to graphitic carbon and pyridinic nitrogen atoms of the nanoflake. The sensitivity of the Ph-g-C3N4-nanoflake-based QCM sensor was found to be the highest (128.99 Hz ppm-1) of the substances studied, with a limit of detection (LOD) of HCOOH down to a sub-ppm level of 80 ppb. This sensing technology based on phenyl-terminated attached-g-C3N4 nanoflakes establishes a simple, low-cost solution to improve the performance of QCM sensors for the effective discrimination of HCOOH, HCHO, and CH3COOH vapors using smart electronic noses.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34559304

RESUMO

We report an efficient and facile approach to biosynthesis of gold nanoparticles (AuNPs) using the extract of an agro-waste rice husk generated from rice production. The biosynthesized NPs produced were characterized by UV-Visible absorption, TEM, XRD, EDX, and FTIR methods. The impact of temperature and pH on the stability of the synthesized AuNPs was also studied. The TEM imaging revealed the formation of monodispersed spherical NPs with an average size of ~ 15 nm. The absorption spectrum of AuNPs demonstrated the formation of Surface Plasmon Resonance (SPR) peak at 530 nm. The XRD pattern suggested the formation of face-centered cubic (FCC) lattice structure of AuNPs. The FTIR analysis displayed characteristic peaks related to various phytochemicals in the plant extract responsible for reducing and stabilizing NPs. In addition, AuNPs showed thermal stability when subjected to various temperature scales. The AuNPs exhibited an efficiency against the pathogenic bacteria Staphylococcus aureus and pathogenic fungi Candida albicans. The AuNPs 18.5% DPPH free scavenging activity, indicating the antioxidant potential for AuNPs. In addition, the AuNPs showed anticancer activity against the colorectal adenocarcinoma carcinoma cell line. Furthermore, AuNPs displayed significant enhancement in photocatalytic degradation of Methylene Blue and 4-Nitrophenol dyes. The results obtained reveal the possible usage of AuNPs produced using rice husk in several biomedical applications.

3.
ACS Omega ; 6(36): 23090-23099, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34549110

RESUMO

In this work, we produced high yield quantized nitrogen-doped graphene nanodiscs from waste tires via a one-step process under high pressure and temperature using a homemade stainless steel reactor without using any chemical additives. Reaction temperature played a vital role in the preparation process. By increasing the temperature to a level between 600 and 1100 °C, the carbon atoms rearranged themselves to build a mixed graphene structure of nanodiscs and quantum dots. The obtained graphene exhibits excellent capacitance and long life cycle stability as an electrode in supercapacitor devices. The specific capacitance rose to 161.24 F/g with a high power density of 733.3 W/kg, and the energy density reached 27.1 Wh/kg. The finding of this work is not only to provide a solution to get rid of hazardous materials but also to give awareness of turning these hazardous materials into a cost-effective and economical nanomaterial; in another, this approach sheds light on the promising power uses of waste.

4.
Int J Biol Macromol ; 190: 927-939, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480910

RESUMO

The incorporation between nano-polyvinyl alcohol (PVA) and nano-chitosan (Cs) to produce sandwich nanohybrid (SNH) for water treatment and improvement the adsorption of sofosbuvir drug (SOF). The photocatalytic activity and formation of reactive oxygen species (ROS) were detected with oxidation of organic dyes such as Rhodamine B (RhB), methylene blue (MB), and methyl orange (MO). The effect of SNH on the release of SOF in blood and inside the cells at pH 7.4 and pH 6.8, respectively were observed by UV-Visible spectroscopy (UV-Vis). The binding constant (Kb) was reported at 0.0035 min-1 and the loading constant at 0.0024 min-1, while the release efficiency was 42.6% at pH 7.4 and 74.7% at pH 6.8. The efficiency of photocatalytic activity against organic dyes MO, MB, and RhB are detected at 2.4% and 1%, and 42%, respectively. The cytotoxicity of SNH has been observed with MDA-MB-231 and HepG2 cell line with three concentrations of SNH, where the little concentration has low effect on the HepG2 and high viability, this result was reversed with the high concentration, also the yellow color due to the lysis of the cells. The antioxidant of the SNH was detected by FRAP technique.

5.
Colloids Surf B Biointerfaces ; 206: 111935, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34252691

RESUMO

Silver nanoparticles (AgNPs) could be employed in the combat against COVID-19, yet are associated with toxicities. In this study, biogenic and biocompatible AgNPs using the agro-waste, non-edible Hibiscus sabdariffa stem were synthesized. Under optimized reaction conditions, synthesized green AgNPs were crystalline, face cubic centered, spherical with a diameter of around 17 nm and a surface charge of -20 mV. Their murine lethal dose 50 (LD50) was 4 folds higher than the chemical AgNPs. Furthermore, they were more murine hepato- and nephro-tolerated than chemical counterparts due to activation of Nrf-2 and HO-1 pathway. They exerted an apoptotic anti-ovarian cancer activity with IC50 value 6 times more than the normal cell line. Being functionalized with polydopamine and conjugated to either moxifloxacin or gatifloxacin, the conjugates exerted an augmented antibiofilm activity against Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii biofilms that was significantly higher than antibiotic alone or functionalized AgNPs suggesting a synergistic activity. In conclusion, this study introduced a facile one-pot synthesis of biogenic and biocompatible AgNPs with preferential anti-cancer activity and could be utilized as antibiotic delivery system for a successful eradication of Gram-negative biofilms.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Prata , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Química Verde , Hibiscus , Indóis , Camundongos , Testes de Sensibilidade Microbiana , Polímeros , Prata/farmacologia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120008, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087770

RESUMO

Self-assembly of Sofosbuvir drug (SOF) anti-hepatitis C virus (HCV) with bio-polymeric nanoparticles such as chitosan nanoparticles (Cs NPs) and polyvinyl alcohol nanoparticles (PVA NPs), the novel composites have been characterized successfully by different analysis such as Energy-dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM), UV-Visible spectrophotometer (UV-Vis) and Fourier Transmittance Infrared (FT-IR). The improvement of the Sofosbuvir effect as a result of loading drug on the bio-polymer NPs surface has been detected by the UV-Vis, and fluorescence spectroscopy techniques. The improvement of SOF efficiency was revealed via studying the drug release of SOF from biopolymers NPs surface at pH 7.4, UV-Vis spectra used for the releasing process. The binding constant (Kb) value was reported at 0.000055 and 0.3613 min-1 for Cs and PVA NPs respectively. Also, the value of KSV was documented at 0.0014 and 7.16 min-1 for Cs@SOF and PVA@SOF hybrid nanocomposite. The incorporation rate (k) of SOF on the surface of biopolymer nano molecules was calculated to be 0.00812 and 0.0165 min-1 for Cs and PVA NPs, respectively. Besides the observed value of (n) was close to the unit 0.74 and 0.86 for Cs and PVA NPs, respectively. The SOF released from Cs NPs surface was documented at 0.09 mg after 24 h, while PVA NPs reported at 0.7 mg at the same time and the release efficiency is 56.5 and 73% for Cs@SOF and PVP@SOF, respectively. From the results, we suggest Cs/SOF and PVA/SOF hybrid nanocomposites have spectroscopic results that make them promising candidate drugs, but need to the clinical trials.


Assuntos
Quitosana , Nanopartículas , Preparações Farmacêuticas , Liberação Controlada de Fármacos , Polímeros , Sofosbuvir , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Int J Biol Macromol ; 182: 1150-1160, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33865895

RESUMO

In the current study, the treatment efficacy of ECHCAH was evaluated in vitro studies using cell viability and flow cytometry in human TNBCs. The results here showed significant gradual reduction in growth of TNBCs (MDA-231cell lines) after their exposure to serial concentrations for hydrogel assembly (5 µg/mL to 25 µg/mL) for 24 and 48 h, representing (86 ± 1% to 45 ± 1.5% p < 0.001) and (79 ± 1.5% to 35 ± 2.5% p < 0.001) respectively. The flow cytometry showed significant increase in the present of late apoptotic and necrotic cells (64% ± 1.2 and 27% ± 0.3 p < 0.001) after 48 h incubation compared to untreated cells (1.13% ± 0.3 and 4% ± 0.2 p < 0.001) respectively. It can be summarized that ECHCA inside targeted hydrogel assemblies can inhibit proliferation of cancer cells.


Assuntos
Carotenoides/química , Quitosana/química , Clorofila/química , Apoptose/fisiologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Feminino , Citometria de Fluxo , Humanos , Hidrogéis/química , Necrose/metabolismo
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 253: 119582, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33636493

RESUMO

This study, investigates the interaction of bovine serum albumin (BSA) with synthesized chitosan nanoparticles (CSNPs) using steady-state fluorescence and UV-vis absorbance spectroscopy as well as picosecond time-resolved fluorescence technique. The fluorescence quenching mechanism of BSA by CSNPs indicates the presence of both static and dynamic mechanism. The loading efficiency of BSA-CSNPs exhibited a decrease by about 6% in neutral pH under physiological temperature. Transmission electron microcopy (TEM) images revealed the Synthesized CSNPs were irregular in shape with size of ~42 nm. The safety and biocompatibility of BSA-CSNPs inside the body was investigated after intraperitoneal (IP) injection of male mice for nine days, analysis of in vivo results, revealed no toxicity with a hypocholesterolemic effect and a predicted mild activation of WBCs due to CSNPs adjuvant and immunogenic peptides in BSA. Accordingly, no signs of hypersensitivity were observed due to the administration of such formulations. The results can be used for a better understanding the interaction of CSNPs within biological protein environment.


Assuntos
Quitosana , Nanopartículas , Animais , Sítios de Ligação , Quitosana/toxicidade , Masculino , Camundongos , Nanopartículas/toxicidade , Soroalbumina Bovina/toxicidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
9.
Int J Biol Macromol ; 167: 1176-1197, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33197477

RESUMO

Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, ß, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.


Assuntos
Bioimpressão/métodos , Quitosana/química , Quitosana/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Nanocápsulas/química , Nanofibras/química , Nanopartículas/química , Engenharia Tecidual/métodos , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Nanocápsulas/ultraestrutura , Nanopartículas/ultraestrutura , Solubilidade , Tecidos Suporte/química
10.
Materials (Basel) ; 13(23)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261031

RESUMO

The introduction of nanoparticles made of polymers, protein, and lipids as drug delivery systems has led to significant progress in modern medicine. Since the application of nanoparticles in medicine involves the use of biodegradable, nanosized materials to deliver a certain amount of chemotherapeutic agents into a tumor site, this leads to the accumulation of these nanoencapsulated agents in the right region. This strategy minimizes the stress and toxicity generated by chemotherapeutic agents on healthy cells. Therefore, encapsulating chemotherapeutic agents have less cytotoxicity than non-encapsulation ones. The purpose of this review is to address how nanoparticles made of polymers and lipids can successfully be delivered into lung cancer tumors. Lung cancer types and their anatomies are first introduced to provide an overview of the general lung cancer structure. Then, the rationale and strategy applied for the use of nanoparticle biotechnology in cancer therapies are discussed, focusing on pulmonary drug delivery systems made from liposomes, lipid nanoparticles, and polymeric nanoparticles. Many nanoparticles fabricated in the shape of liposomes, lipid nanoparticles, and polymeric nanoparticles are summarized in our review, with a focus on the encapsulated chemotherapeutic molecules, ligand-receptor attachments, and their targets. Afterwards, we highlight the nanoparticles that have demonstrated promising results and have been delivered into clinical trials. Recent clinical trials that were done for successful nanoparticles are summarized in our review.

11.
Front Chem ; 8: 561052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324607

RESUMO

A low-cost, simple, and highly selective method was used for the assessment of total prostate specific antigen (tPSA) in the serum of prostate cancer patients. This method is based on quenching the intensity of luminescence displayed by the optical sensor Eu (TTA)3 phen/poly methylmethacrylate (PMMA) thin membrane or film upon adding different concentrations of tPSA. The luminescent optical sensor was synthesized and characterized through absorption, emission, scanning electron microscopy (SEM), and x-ray diffraction (XRD), and is tailored to present red luminescence at 614 nm upon excitation at 395 nm in water. The fabricated sensor fluorescence intensity is quenched in the presence of tPSA in aqueous media. The fluorescence resonance energy transfer (FRET) is the main mechanism by which the sensor performs. The sensor was successfully utilized to estimate tPSA in the serum of patients suffering prostate cancer in a time and cost effective way. The statistical results of the method were satisfactory with 0.0469 ng mL-1 as a detection limit and 0.99 as a correlation coefficient.

12.
Mater Sci Eng C Mater Biol Appl ; 116: 111119, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806233

RESUMO

Curcumin is a more efficient polyphenol than many chemotherapeutics. It can inhibit many signaling pathways at the same time resulting in modulation and down regulation for many oncogenic activities, tumor suppressor genes, several transcription factors and their signaling pathways. However it is still not employed as a potential therapeutic tool for cancer treatment. This is due to its hydrophobicity, its hypersensitivity and its poor adsorption. Many trials have been applied for encapsulating curcumin as a delivery system thinking to save its biological benefits. In our recent work, encapsulated curcumin was successfully used to produce bio cross-linkers for mucoadhesive polymer forming multi branched or flower like shape. Moreover, this strategy is not used only to save its biological function, but also to provide a novel bio cross-linker for hydrogel system. This study was investigated by using scanning electron microscopy, FTIR, U-V Visible Spectroscopy. Encapsulated curcumin provides promising bio safe cross-linker for optimizing hydrogel system, since carboxymethyl cellulose raises its ability to penetrate mucus layer. Additionally, flow cytometry and cytotoxicity show ability of encapsulated curcumin to inhibit proliferation of liver cancer cells.


Assuntos
Curcumina , Neoplasias Hepáticas , Nanopartículas , Carboximetilcelulose Sódica , Curcumina/farmacologia , Portadores de Fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico
13.
ACS Omega ; 5(11): 5629-5637, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32226838

RESUMO

We developed a novel, simple, sensitive, accurate, and precise method for the determination of calcitonin in different serum samples with medullar thyroid carcinoma. The designed flower-like thin film gold nanoparticles doped in a sol-gel/polyethylene glycol mold are used as an optical biosensor for the efficient determination of calcitonin. The sensor was characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray microanalysis, and Fourier-transform infrared spectroscopy. The efficiency of the considered bio-sensor is done using the quencher calcitonin of the emission band at 360 nm of biomarker obtained at λex = 333 nm in acetonitrile solvent. The sensing mechanism was based on fluorescence resonance energy transfer. The remarkable quenching of the fluorescence intensity at 360 nm of optical sensor by various concentrations of calcitonin was successfully used as an optical biosensor for the assessment of calcitonin for different serum samples of patients with medullar thyroid carcinoma. The calibration plot was prepared for the concentration range 0.01-1000 pg/mL of calcitonin with a correlation coefficient of 0.99 and a detection limit of 0.707 pg/mL. The suggested method augments the sensitivity of calcitonin as a useful biomarker for the early diagnosis of medullar thyroid carcinoma. This method is considered as a gateway for the construction of a new prototype for the follow-up of thyroid cancer in the spinal cord during and after treatment.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117811, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31813731

RESUMO

The interaction of bovine serum albumin (BSA) with seven-coordination iron (II) complex containing sulfur-based macrocyclic ligand was investigated by means of UV/vis absorption spectroscopy and fluorescence quenching technique. The accurate fluorescence spectra are obtained by using Inner filter effect (IFE) correction. The apparent association constant, kapp, the number of binding sites, n, and the apparent binding constant KSV were found to be 0.95 × 103 M-1, 0.96, and 6.13 × 104 M-1, respectively. It found that BSA molecules are adsorbed on the surface of iron (II) complex by electrostatic interaction. The quenching mechanism is discussed involving energy transfer from BSA to iron (II) complex.


Assuntos
Ligantes , Soroalbumina Bovina/química , Espectrofotometria/métodos , Animais , Bovinos , Simulação por Computador , Análise Mutacional de DNA , Ligação de Hidrogênio , Imageamento Tridimensional , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Mutação , Domínios Proteicos , Transdução de Sinais , Termodinâmica
15.
Photochem Photobiol Sci ; 18(8): 2071-2079, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31259348

RESUMO

We herein report the supramolecular self-assembly of a water soluble porphyrin, namely, 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin-tetra(p-toluenesulfonate) (TMPyP), on the surface of graphene oxide (GO). The fabricated GO nanosheet and GO@TMPyP hybrid material composite have been characterized by using various spectroscopic and analytical techniques, e.g., scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. The steady state absorption measurements of the GO@TMPyP self-assembly showed a significant red shift (∼20 nm) compared to those of the control TMPyP in water. The steady state fluorescence measurements showed a significant fluorescence quenching of the singlet excited state of TMPyP in the presence of GO. These findings suggest the electron transfer reaction from TMPyP to GO. The time resolved fluorescence measurements showed a considerable decrease in the lifetime of the singlet state of TMPyP in the presence of GO, from which the rate and efficiency of the electron transfers from TMPyP to GO were determined to be 1.93 × 109 s-1 and 91%, respectively. The transient absorption measurements showed a considerable quenching of the triplet excited state of TMPyP in the self-assembly. All these findings confirm the occurrence of efficient electronic interactions between TMPyP and GO in both the ground and excited states. In addition, the fabricated GO@TMPyP showed high photocatalytic activity for the degradation of methylene blue (MB) and methyl orange (MO) mixed dye pollutants in water under visible light irradiation.

16.
Talanta ; 201: 185-193, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122410

RESUMO

A novel, simple, sensitive, and precise spectrofluorometric assay of cancer antigen [CA 125] is described. This modality is based on monitoring the quenching of the luminescence intensity at 790 nm of the phthalocyanine fluorophore, in a nanocomposite comprising the fluorophore and cationic polystyrene, which results from interaction with CA 125. The remarkable quenching of the luminescence intensity of the Ni-phthalocyanine complex doped in PS matrix by various concentrations of CA 125 was successfully utilized as an optical sensor for the determination of CA 125 in different serum samples of ovarian disease. The performance of the designed biosensor is determined through monitoring the quenching of the luminescence intensity at 790 nm by cancer antigen 125 after excitation at 685 nm, pH 7.3 in water. The calibration plot was achieved over the concentration range 1.0 × 10-2 - 127 U mL-1 CA-125 with a correlation coefficient of 0.99 and detection limit of 1.0 × 10-4 U mL-1. The mechanism of the interaction between the nano thin film nickel(II)phthalocyanine and CA-125 was discussed. A significant correlation between the proposed method for the assessment of CA 125 and the standard method was applied to patients and controls.


Assuntos
Técnicas Biossensoriais/métodos , Antígeno Ca-125/sangue , Corantes Fluorescentes/química , Indóis/química , Proteínas de Membrana/sangue , Nanocompostos/química , Poliestirenos/química , Biomarcadores Tumorais/sangue , Feminino , Fluorescência , Corantes Fluorescentes/síntese química , Humanos , Indóis/síntese química , Limite de Detecção , Níquel/química , Neoplasias Ovarianas/sangue , Poliestirenos/síntese química , Espectrometria de Fluorescência/métodos
17.
Talanta ; 199: 89-96, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952321

RESUMO

A new highly green luminescent binuclear palladium 2-pyrazinecarboxamide-bipyridine complex [Pd(pyc)(bpy)] was prepared and characterized. The binuclear Pd(pyc)(bpy) complex doped in sol-gel matrix has a strong luminescence intensity at 547 nm with λex = 330 nm in water The method depends on the quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex at 547 nm by different concentrations of uric acid. The remarkable quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex, doped in a sol-gel matrix, by uric acid was successfully used for the determination of uric acid in serum samples of patients with hypouricemia disease. The calibration plot was achieved over the concentration 3.9 × 10-9 to 1.2 × 10-4 mol L-1uric acid with a correlation coefficient of 0.9 and a detection limit of 1.8 × 10-10 mol L-1. The method was used satisfactorily for the assessment of the uric acid in a number of serum samples collected from various patients with Hypouricemia disease.


Assuntos
2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Complexos de Coordenação/química , Dispositivos Ópticos , Paládio/química , Pirazinas/química , Ácido Úrico/sangue , 2,2'-Dipiridil/síntese química , Carcinoma Hepatocelular/sangue , Doenças Cardiovasculares/sangue , Complexos de Coordenação/síntese química , Géis , Humanos , Neoplasias Hepáticas/sangue , Imagem Óptica , Pirazinas/síntese química
18.
Carbohydr Polym ; 197: 17-28, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30007602

RESUMO

High efficient 3,5-Dinitrosalicylic acid/Chitosan/MnFe2O4 (DNSA@CS@MnFe2O4) nano photocatalyst was prepared to enrich both adsorption and photodecomposition under visible light. This paper focused on the importance of DNSA@CS as an excellent connector between methylene blue (MB) and MnFe2O4 for accelerating photodegradation with the encouragement of photo-Fenton catalytic reagent hydrogen peroxide (H2O2). The optimum conditions were: contact time, 30 min, H2O2 concentration, 0.16 M, pH factor 9 and dosage 0.06 g/l at R.T, allowing excellent catalytic achievements 98.9% degree of decolorization in 30 min. More interestingly, the hybrid DNSA@CS@MnFe2O4 mechanism explained on the basis of coexistence of Mn2+/Mn3+ and Fe3+/Fe2+ redox couples during the reaction. The photocatalytic decolorization experimentally affirmed the suitability of DNSA@CS@MnFe2O4 obeying Langmuir-Hinshelwood model. Also, the nano-catalytic system was stable even after five runs. The prepared nanostructured catalyst provides simple fabrication to promote deep understand criteria for the mechanistic role of MnFe2O4 catalyst for degradation of MB molecules.


Assuntos
Quitosana/química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Compostos de Manganês/química , Azul de Metileno/química , Nanopartículas/química , Salicilatos/química , Catálise , Luz , Conformação Molecular , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície
19.
Cancers (Basel) ; 10(7)2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30037052

RESUMO

Micelles as colloidal suspension have attracted considerable attention due to their potential use for both cancer diagnosis and therapy. These structures have proven their ability to deliver poorly water-soluble anticancer drugs, improve drug stability, and have good penetration and site-specificity, leading to enhance therapeutic efficacy. Micelles are composed of hydrophobic and hydrophilic components assembled into nanosized spherical, ellipsoid, cylindrical, or unilamellar structures. For their simple formation, they are widely studied, either by using opposite polymers attachment consisting of two or more block copolymers, or by using fatty acid molecules that can modify themselves in a rounded shape. Recently, hybrid and responsive stimuli nanomicelles are formed either by integration with metal nanoparticles such as silver, gold, iron oxide nanoparticles inside micelles or by a combination of lipids and polymers into single composite. Herein, through this special issue, an updated overview of micelles development and their application for cancer therapy will be discussed.

20.
Vet Res Commun ; 41(4): 263-277, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29098532

RESUMO

The interactions between gastric microbiota, ovine host, and Haemonchus contortus portray the ovine gastric environment as a complex ecosystem, where all factors play a pertinent role in fine-tuning each other and in haemeostasis. We delineated the impact of early and late Haemonchus infection on abomasal and ruminal microbial community, as well as the ovine host. Twelve, parasite-naive lambs were divided into four groups, 7 days post-infection (dpi) and time-matched uninfected-control groups; 50 dpi and time-matched uninfected control groups were used for the experiment. Six sheep were inoculated with 5000 H. contortus infective larvae and followed for 7 or 50 days with their corresponding uninfected-control ones. Ovine abomasal tissues were collected for histological analysis and gastric fluids were collected for PH value measurements, microbial community isolation and Illumina MiSeq platform and bioinformatic analysis. Our results showed that Haemonchus infection increased the abomasal gastric pH (P = 0.05) and resulted in necrotizing and inflammatory changes that were more severe during acute infection. Furthermore, infection increased the abomasal bacterial load and decreased the ruminal microbiome. A 7-day infection of sheep with H. contortus significantly altered approximately 98% and 94% of genera in the abomasal and ruminal bacterial profile, respectively (P = 0.04-0.05). However, the approximate altered genera 50 days after infection in the ovine abomasal and ruminal microbiome were about 62% and 69%, correspondingly (P = 0.04-0.05) with increase in some bacteria and decrease in others. Overall, these results indicate that Haemonchus infection plays a crucial role in shaping stomach microbial community composition, and diversity.


Assuntos
Biodiversidade , Hemoncose/veterinária , Interações Hospedeiro-Patógeno , Microbiota/fisiologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/parasitologia , Abomaso/química , Abomaso/microbiologia , Abomaso/parasitologia , Abomaso/patologia , Animais , Bactérias/classificação , Bactérias/genética , Hemoncose/microbiologia , Hemoncose/parasitologia , Hemoncose/patologia , Haemonchus , Concentração de Íons de Hidrogênio , RNA Ribossômico 16S/genética , Rúmen/química , Rúmen/microbiologia , Rúmen/parasitologia , Rúmen/patologia , Ovinos , Doenças dos Ovinos/patologia , Fatores de Tempo
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