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1.
BMC Cardiovasc Disord ; 24(1): 64, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263001

RESUMEN

BACKGROUND AND OBJECTIVE: Heart rhythm disorder is one of the most common problems after coronary artery bypass graft surgery. Various factors, such as the history of sleep apnoea before the operation, may aggravate the occurrence of this disorder. The present study was conducted to determine the relationship between sleep apnoea before surgery and heart rhythm disorder after surgery in patients undergoing coronary Artery Bypass Grafting in 2019. METHODS: This analytical cross-sectional study was conducted on 192 patients who were selected by sequential sampling. The research tool included demographic information, a checklist of heart rhythm disorders, and the Berlin sleep apnoea questionnaire. Descriptive statistics and the Chi-square test, Fisher's exact test, Mann-Whitney's U-test, and logistic regression were used to analyze the data. RESULTS: A total of 71.35% of the samples were male, and the mean age of the participants was 57.8 ± 7.5 years. Also, 46.0% of the samples had sleep pane and 21.35% had rhythm disorder. The most frequent heart rhythm disorder in patients with obstructive sleep apnoea was atrial fibrillation. There was a significant relationship between the occurrence of rhythm disorder and a history of smoking (P = 0.021), and the regression model showed that a history of smoking is the only variable related to the occurrence of rhythm disorder after coronary Artery Bypass Grafting (P = 0.005, CI 95%: 6.566-1.386, OR = 3.017). CONCLUSIONS: The results showed that there is no statistically significant relationship between sleep apnea and rhythm disorder after coronary artery bypass surgery.


Asunto(s)
Fibrilación Atrial , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Estudios Transversales , Trastorno del Sistema de Conducción Cardíaco , Puente de Arteria Coronaria
2.
J Fluoresc ; 32(1): 145-153, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34643855

RESUMEN

Herein, we designed a sensitive and selective "Turn-On" fluorescence nanosensor using water-soluble carbonaceous fluorescent nanomaterials (CFNs) functionalized with thiourea (CFNs-Thiourea) for efficient detection of trace concentrations of arsenic (III) in aqueous samples. The CFNs and CFNs-Thiourea were characterized by transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis) and fourier transformed infrared spectroscopy (FTIR). The emission peak intensity of proposed nanosensor at 425 nm was gradually enhanced on arsenite addition in a wide detection range (3.3-828.5 µg L-1) attributed to the binding of arsenite species with sulfur groups of CFNs-Thiourea. The limit of detection (LOD) was 0.48 µg L-1 being much lower than the World Health Organization (WHO) recommended threshold value of 10 µg L-1. Furthermore, the as-prepared CFNs-Thiourea exhibited a superb selectivity for As (III) compared to various cations and anions, such as; NO3-, NO2-, F-, Ni2+, Fe3+, Cu2+, Ca2+, Mg2+, Zn2+, Fe2+, Hg2+, Pb2+, F-, Cl-, Mn2+, Cr3+, Co2+, Cd2+, Bi3+, Al3+ and As (V) at 100 folds concentration of As (III). The turn on fluorescence nanosensor was successfully exploited for quantification of arsenic in spiked water samples with acceptable efficiencies.


Asunto(s)
Arsénico/análisis , Fluorescencia , Colorantes Fluorescentes , Nanopartículas , Nanoestructuras , Tiourea/química , Agua/química , Límite de Detección
3.
J Fluoresc ; 32(5): 1733-1741, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35675001

RESUMEN

In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis) detection. For this purpose, water-soluble synthesized CDs were functionalized with 19 mer-modified oligonucleotides (capture probe). By adding the DNA target, the specific binding between the DNA probe and DNA target causes fluorescence quenching. The assay displayed a fine capability of sensing the BRCA1 gene with a linear range (R2 = 0.9918) of 36 attomolar (aM) to 532 femtomolar (fM) and a detection limit of 2 attomolar. This homogeneous process does not need additional separation and washing steps of un-hybridized DNA. To assess the selectivity, the prepared biosensor responses were evaluated in solutions containing single-base mismatched DNA sequences, three-base mismatched DNA sequences, or non-complementary DNA sequences, separately. To demonstrate the practical application of the designed biosensor, the extracted DNA from blood samples of breast cancer patients was utilized as real samples. When the CDs-DNA bioassay was exploited in the imaging of MCF-7 cancer cells, strong fluorescence emission was observed. After incubation times, both the cells' size and shape remained unchanged. The results validated that the CDs are an extremely great bioimaging candidate in disease diagnosis, biomedicine investigation, and managing cancer diseases.


Asunto(s)
Neoplasias de la Mama , Puntos Cuánticos , Proteína BRCA1/genética , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/genética , Carbono , ADN/genética , Femenino , Colorantes Fluorescentes , Genes BRCA1 , Humanos , Espectrometría de Fluorescencia/métodos
4.
J Nanobiotechnology ; 20(1): 73, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35135571

RESUMEN

BACKGROUND: MicroRNAs have short sequences of 20 ~ 25-nucleotides which are similar among family members and play crucial regulatory roles in numerous biological processes, such as in cell development, metabolism, proliferation, differentiation, and apoptosis. RESULTS: We reported a strategy for the construction of a dual-emission fluorescent sensor using carbon dots (CDs) and confirmed their applications for ratiometric microRNA-21 sensing and bioimaging of cancer cells in a microfluidic device. The composition of blue CDs (B-CDs) and yellow CDs (Y-CDs) depicts dual-emission behavior which is centered at 409 and 543 nm under an excitation wavelength of 360 nm. With increasing microRNA-21 concentration, the robust and specific binding of DNA probe functionalized B-CDs to complementary microRNA-21 target induced perturbations of probe structure and led to changing fluorescence intensity in both wavelengths. Consequently, the ratio of turn-on signal to turn-off signal is greatly altered. With monitoring of the inherent ratiometric fluorescence variation (ΔF540nm/ΔF410nm), as-prepared BY-CDs were established as an efficient platform for ratiometric fluorescent microRNA-21 sensing, with a wide linear range of 0.15 fM to 2.46 pM and a detection limit of 50 aM. CONCLUSIONS: Furthermore, the proposed assay was applied for detecting microRNA-21 in dilute human serum samples with satisfactory recovery and also in MCF-7 cell lines in the range 3000 to 45,000 (cell mL-1) with a detection limit (3 cells in 10 µL), demonstrating the potential of the assay for clinic diagnosis of microRNA-associated disease. More importantly, the images revealed that MCF-7 cells well labeled with BY-CDs could exhibit the applicability of the proposed microfluidic system as an effective cell trapping device in bioimaging.


Asunto(s)
MicroARNs , Puntos Cuánticos , Carbono/química , Colorantes Fluorescentes/química , Humanos , Células MCF-7 , Microfluídica , Puntos Cuánticos/química
5.
Mikrochim Acta ; 187(5): 312, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32367346

RESUMEN

A practical technique was applied to fabricate MoWS2 nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. The characterization of MoWS2 nanocomposite was investigated by several techniques to identify the size, crystal structure, and elemental composition. MoWS2 nanocomposite exhibited a unique and well-defined hierarchical structure with neatly and densely piled nanopetals acting as the active sites in the electrocatalytic reactions. A carbon screen-printed electrode (CSPE) modified with interesting MoWS2 nanopetals (MoWS2/CSPE) was constructed. Subsequently, the electrochemical oxidation of morphine on fabricated MoWS2/CSPE was studied. Experimental results confirm that under optimized conditions, the maximum oxidation current of morphine occurs at 275 mV in the case of MoWS2/CSPE that is around 100 mV more negative than that observed in the case of the unmodified CSPE and about 2.6 times increase was observed for the oxidation peak current. The analytical approach was obtained by differential pulse voltammetry in accordance with the relationship between the oxidation peak current and the morphine concentration. The oxidation peak currents for morphine were found to vary linearly with its concentrations in the range of 4.8 × 10-8-5.05 × 10-4 M with the detection limit of 1.44 × 10-8 M. Two completely separated signals occured at the potentials of 275 mV and 920 mV for oxidation of morphine and tramadol at the surface of MoWS2/CSPE which are sufficient for determination of morphine in the presence of tramadol. The presence of morphine was also detected in real samples using the introduced approach. Graphical abstract Schematic representation of fabrication of the MoWS2 nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. A carbon screen-printed electrode was modified with MoWS2 nanocomposite. Subsequently, the electrochemical oxidation of morphine on the fabricated electrode was studied.


Asunto(s)
Técnicas Electroquímicas/métodos , Morfina/orina , Nanocompuestos/química , Tramadol/orina , Carbono/química , Electrodos , Humanos , Límite de Detección , Molibdeno/química , Reproducibilidad de los Resultados , Sulfuros/química , Compuestos de Tungsteno/química
6.
Mikrochim Acta ; 186(4): 231, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30850906

RESUMEN

This short review (with 72 refs.) summarizes the state of the art in fluorometric methods for targeted imaging of cancer cells and tumor tissues in order to differentiate between normal cells and cancer cells. Following an introduction into the field and after presenting an overview on the most commonly used carbon dots and graphene quantum dots, we describe methods based on peptide based targeting, aptamer based targeting, antibody based targeting, and ligand-based targeting. A concluding section summarizes the current state and challenges, and discusses future perspectives. Graphical abstract An overview is given on the applications of carbon dots (CDs) in target-specific imaging and differentiation of cancerous cells from normal cells. Several classes of ligands (including aptamers, peptides, antibodies), especially small molecules (such as FA)) have been reported for functionalizing of CDs.


Asunto(s)
Carbono/química , Colorantes Fluorescentes/química , Neoplasias/diagnóstico , Puntos Cuánticos/química , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Humanos , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos
7.
Anal Biochem ; 557: 18-26, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29908158

RESUMEN

We proposed a FRET immunosensing for detection of CA15-3 tumor marker by highly biospecific interactions between CA 15-3 antigen and the corresponding antibody and aptamer. In this sandwich type immunoassay, CA15-3 antibody-functionalized carbon dots and AuNPs labeled PAMAM-Dendrimer/aptamer were used as donor/acceptor, respectively. When CA 15-3 Ag was added to homogenous immunoassay, the strong complex interaction between CA15-3 Ab-CA15-3 Ag- aptamer caused in more coming closer carbon dot and AuNPs and more decreasing fluorescence signal. The decreased fluorescence intensity was linear at three ranges including in concentration range 1.1 µUmL-1 to 16 µU mL-1 with regression of R2 = 0.9879, at the concentration range 16 µU mL-1 to 0.163 mU mL-1 with regression of R2 = 0.9944 and at the concentration range 0.163 mU mL-1 to 5.0 mU mL-1 with regression of R2 = 0.9805. The detection limit of the FRET immunoassay was 0.9 µU mL-1. This assay revealed good sensitivity and specificity with MDA-MB-231 breast cancer cells concentrations from 1000 to 40000 cells/mL with correlation coefficient of 0.9955 and detection limit of 300 cells/mL (3 cells in 10 µL of injected sample). In addition, this FRET immunosensing is applicable in diluted human serum. The recovery values were in the range of 95.86-96.97% for CA 15-3 Ag in spiked serum sample with RSD lower than 7.3%. The proposed immunoassay could be a valid model for establishing other immunoassays for detection of different cancer tumor markers with relevant antigens and antibodies.


Asunto(s)
Anticuerpos/química , Aptámeros de Nucleótidos/química , Biomarcadores de Tumor/sangre , Dendrímeros/química , Transferencia Resonante de Energía de Fluorescencia , Inmunoensayo , Mucina-1/sangre , Anticuerpos/inmunología , Reacciones Antígeno-Anticuerpo , Biomarcadores de Tumor/inmunología , Carbono/química , Oro/química , Humanos , Luminiscencia , Nanopartículas del Metal/química , Mucina-1/inmunología , Células Tumorales Cultivadas
8.
Mikrochim Acta ; 185(8): 372, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29995191

RESUMEN

A fluorometric method is presented for sensitive deternination of microRNA. It is making use of carbon dots (C-dots) loaded with a DNA probe as fluorophore and MnO2 nanosheets as the quenching agent. The blue-green fluorescence of the DNA-loaded C-dots is quenched by the MnO2 nanosheets, but restored on binding target microRNA-155. The maximum excitation wavelength and the maximum emission wavelength of C-dots are at 360 nm and 455 nm, respectively. Fluorescence correlates linearly with the log of the microRNA-155 concentration in two ranges, viz. from 0.15 to 1.65 aM and from 1.65 to 20 aM. The detection limit is as low as 0.1 aM. The assay can discriminate between fully complementary and single-base mismatch microRNA. The assay displayed high specificity when used to detect MCF-7 breast cancer cells which can be detected in concentrations from 1000 to 45,000 cells·mL-1, with a 600 cells·mL-1 detection limit. The method was applied to the analysis of serum samples spiked with microRNA, and satisfactory results were acquired. Graphical abstract Schematic of a fluorometric sensing platform for miRNA-155. The method relies on a FRET process between C-dots and MnO2 nanosheets. This strategy has a practical application for detection of miRNA in cell lines and biological fluids.

9.
J Org Chem ; 82(11): 5516-5523, 2017 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-28470064

RESUMEN

The first cinchona-alkaloid-organocatalyzed enantioselective synthesis of chiral 1,4-dihydropyridine derivatives is described. Bis-cinchona catalyst 3b activates the Michael addition reaction between malononitrile derivatives 2 and enamines 1, affording the appealing and highly substituted 1,4-dihydropyridines 4 with very good results in most cases. This is one of very few examples of the synthesis of chiral 1,4-dihydropyridines by an enantioselective catalytic procedure. The highly substituted final compounds are of interest for their potential biological activity. This efficient protocol opens the door to a new area of research for the asymmetric construction of these skeletons for which enantioselective syntheses are still very limited.

10.
Molecules ; 20(9): 15807-26, 2015 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-26334263

RESUMEN

Herein, we report our preliminary results concerning the first promising asymmetric synthesis of highly functionalized 2-oxospiro-[indole-3,4'-(1',4'-dihydropyridine)] via the reaction of an enamine with isatylidene malononitrile derivatives in the presence of a chiral base organocatalyst. The moderate, but promising, enantioselectivity observed (30%-58% ee (enantiomeric excess)) opens the door to a new area of research for the asymmetric construction of these appealing spirooxindole skeletons, whose enantioselective syntheses are still very limited.


Asunto(s)
Dihidropiridinas/química , Indoles/química , Catálisis , Estructura Molecular , Compuestos de Espiro/química , Estereoisomerismo
11.
Birth Defects Res ; 116(7): e2379, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38958465

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is the fastest-growing child neuropsychiatric condition. Cognitive dysfunctions such as memory impairments are experienced by patients along with social disturbances and repetitive/stereotypic movements. We have used the radial arm maze (RAM), for measurement of working and reference memory errors in an animal model of autism. In addition, the potential effects of agmatine, an endogenous NMDA antagonist, on RAM performance and autistic-like behaviors were assessed. METHODS: Autism was modeled by valproic acid (VPA) administration at gestational Day 12.5. Autism-associated behaviors in male offspring were examined in an open field test (OFT) and three-chambered test (TCT) on postnatal days 50-51. Thereafter, the animals were trained in the RAM (PND 55) until they attained the criteria of 80% correct choices during five consecutive trials. Forty-eight hours after the acquisition of criteria, agmatine was injected 30 min before subsequent behavioral testing, which included the retention phase of the RAM, OFT, and TCT. RESULTS: VPA-treated and intact rats showed the same performance in RAM, and acute injection of agmatine rescued social and anxiety-like behavior induced by VPA without the effect on RAM. CONCLUSION: In a rat model of autism, spatial learning, and memory did not change. Agmatine rescued social and anxiety-like behavior in autistic animals.


Asunto(s)
Agmatina , Trastorno Autístico , Conducta Animal , Modelos Animales de Enfermedad , Aprendizaje por Laberinto , Animales , Agmatina/farmacología , Masculino , Ratas , Aprendizaje por Laberinto/efectos de los fármacos , Trastorno Autístico/tratamiento farmacológico , Trastorno Autístico/psicología , Conducta Animal/efectos de los fármacos , Memoria/efectos de los fármacos , Ácido Valproico/farmacología , Femenino , Embarazo
12.
Acta Parasitol ; 69(1): 549-558, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38231310

RESUMEN

PURPOSE: Leishmania major is main causative agent and Phlebotomus papatasi is only proven vector of Zoonotic Cutaneous Leishmaniasis (ZCL) in Iran. Human leishmaniasis is mostly susceptible to climatic conditions and molecular variations of Leishmania parasites within sandflies. METHODS: L. major was analyzed based on geographical, environmental, climatic changes and haplotype variations within P. papatasi. Molecular tools and different geographical aspects were employed using Arc-GIS software for mapping the geographic distribution of samples and other statistics tests. Fragments of ITS-rDNA, k-DNA, and microsatellite genes of Leishmania were used for PCR, RFLP, sequencing, and phylogenetic analyses. RESULTS: Totally 81 out of 1083 female P. papatasi were detected with Leishmania parasites: 70 and five were L. major and L. turanica, respectively. Golestan and Fars provinces had the highest (13.64%) and lowest (4.55%) infection rates, respectively. The infection rate among female P. papatasi collected from gerbil burrows was significantly higher (15.15%) than animal shelters, yards, and inside houses (4.48%) (P < 0.0%). Microsatellite was more sensitive (22.72%) than k-DNA (18.8%) and ITS-rDNA (7.48%). More molecular variations of L. major were found in Isfahan province. CONCLUSIONS: Arc-GIS software and other statistics tests were employed to find Leishmania positive and haplotype variations among sand flies. Geographical situations, altitude, climate, precipitation, humidity, temperature, urbanization, migrations, regional divergences, deforestation, global warming, genome instability, ecology, and biology of the sand flies intrinsically, and the reservoir hosts and neighboring infected locations could be reasons for increasing or decreasing the rate of Leishmania infection and haplotype variations.


Asunto(s)
Haplotipos , Leishmania major , Leishmaniasis Cutánea , Phlebotomus , Animales , Leishmania major/genética , Leishmania major/aislamiento & purificación , Phlebotomus/parasitología , Phlebotomus/genética , Irán/epidemiología , Femenino , Leishmaniasis Cutánea/parasitología , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/transmisión , Filogenia , Variación Genética , Repeticiones de Microsatélite , Insectos Vectores/parasitología , Insectos Vectores/genética , ADN Protozoario/genética , Gerbillinae/parasitología , Humanos
13.
Waste Manag ; 170: 308-316, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37738758

RESUMEN

In a previous study, we demonstrated the efficient depolymerization of polyethylene terephthalate (PET) through glycolysis using antimony (III) oxide, a commonly used catalyst in PET synthesis. In the present research, we introduce a novel approach involving the synthesis of a magnetic bifunctional ionic liquid, Fe3O4@PMIM.SbBr4, containing only 2.2 wt% of antimony. The aim is to reduce the required antimony dosage for the reaction and enable its facile recovery and reuse. By employing this catalyst in PET chemical recycling through glycolysis to generate bis (2-hydroxyethyl) terephthalate (BHET) monomer, we achieved 100% PET conversion with a 96.4% yield and selectivity for BHET. This outcome was obtained using a catalyst loading of 6.0 wt% at 200 °C and 0.6 bar in a high-pressure reactor. We explored the impact of catalyst loading on BHET yield and conducted a comparative assessment of the Fe3O4@PMIM.SbBr4 catalyst against antimony (III) bromide, and another synthesized unsupported antimony-containing ionic liquid. Our results revealed the superior catalytic activity of the magnetic ionic liquid catalyst in PET glycolysis. The utilization of this catalyst offers promising potential for PET glycolysis due to its effortless separation using an external magnet, ability to produce highly pure BHET, and recyclability for repetitive use.

14.
BMC Sports Sci Med Rehabil ; 15(1): 47, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36978202

RESUMEN

BACKGROUND: Studies have revealed that high-intensity interval training (HIIT) has beneficial effect on hormonal, cardiovascular indices in women with polycystic ovary syndrome (PCOS). There, however, is still no comprehensive data on the type, intensity and duration of training for these women. OBJECTIVE: The current study aimed to investigate the effects of high-intensity interval training (HIIT) on metabolic, hormonal and cardiovascular indices in women with PCOS compared to a control group. METHODS: In a randomized controlled study, 28 patients (age: 23.8 ± 5.3 years, weight: 82.4 ± 9.7 kg, BMI: 30.33 ± 3.99 kg/m2) were divided into two groups including HIIT (n = 14) and the control (n = 14). The training protocol was performed with 100-110 maximum aerobic velocity (MAV), 4-6 sets, 4 laps, 3 sessions per week for eight weeks. Anthropometric indices, aerobic performance, insulin resistance and sensitivity, lipid profiles, testosterone, cortisol and hs-CRP were evaluated. RESULTS: The HIIT intervention decreased BMI, waist to hip ratio (WHR), visceral fat, insulin, insulin resistance, low density lipoprotein (LDL), atherogenic index, cholesterol and cortisol (P < 0.05). All variables remained unchanged in the control group (P > 0.05). Except for VAI, FBG, HDL, TG and AIP, the rest of the variables in the training and control groups show a significant difference (P < 0.05). CONCLUSION: The results of the present study indicate that eight weeks of HIIT has beneficial effects on anthropometric, insulin sensitivity, fat profile, and inflammatory and cardiovascular indices in PCOS patients. It seems that the intensity of HIIT (100-110 MAV) is a determining factor in creating optimal adaptations in PCOS patients. TRAIL REGISTRATION: IRCT20130812014333N143. Registration date: 22/03/2020. URL: https://en.irct.ir/trial/46295 .

15.
ACS Appl Polym Mater ; 5(8): 6574-6584, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37588081

RESUMEN

We report here the production of higher-order oligomers from the glycolysis of poly(ethylene terephthalate) (PET) by using microwave irradiation in a controlled fashion, instead of its fully glycolyzed product, bis(2-hydroxyethyl)terephthalate (BHET). We show that different catalysts can generate either BHET as the ultimate glycolysis product or higher oligomers of PET under microwave irradiation. Depolymerization of waste PET with an average degree of polymerization (DP) of 417 from water bottles was performed in the presence of 0.25 wt % antimony(III) oxide (Sb2O3) as the catalyst at 240 °C and 400 W microwave power, resulting in an oligomer yield of 96.7% with an average DP of 37. Under these conditions, the conversion of PET to oligomers reached 100% in only 5 min at 240 °C (with a 10 min ramping time) and with a ethylene glycol to PET weight ratio of 2.5. In comparison, under the same reaction conditions, 0.04 wt % of zinc acetate (Zn(OAc)2), a well-known catalyst for PET glycolysis, produces only the BHET monomer in 96.3% yield. Our results demonstrated that by using Sb2O3, the same catalyst that is used extensively for PET synthesis from BHET, under microwave irradiation, the PET glycolysis can be controlled to produce higher PET oligomers as an alternative for a complete chemical depolymerization to the BHET monomer. These oligomers are more suitable for being used as additives for many applications and to produce high-quality second-generation products, including regenerated PET.

16.
ACS Sustain Chem Eng ; 11(46): 16618-16626, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38028403

RESUMEN

We report using a waste material, poly(ethylene terephthalate) (PET) water bottle labels, for the chemical recycling of the same PET water bottles. The solid fillers used for the manufacturing of the packaging labels were recovered by thermolysis in an electrical furnace at 600, 800, and 1000 °C with 13.5, 12.0, and 10.4 wt % recovery. Characterization of the solid residue showed the presence of calcium carbonate, calcium oxide, and titanium dioxide, which are typical fillers used for packaging film manufacturing, such as water bottle labels. These solid residues were then used as a catalyst for PET depolymerization by glycolysis, in which the catalyst recovered from bottle labels and shredded PET reacted in the presence of excess ethylene glycol at 200 °C. The reaction mixtures were analyzed for PET conversion and the yield of the bis(2-hydroxyethyl)terephthalate (BHET) monomer as the final product of the glycolysis reaction to determine the efficiency of the catalyst. Our results show that the catalyst prepared at 800 °C (Cat-800) has the best performance and provides a 100% PET conversion with a 95.8% BHET yield with a 1.0 wt % loading in 1.5 h. The catalyst from the PET water bottle labels is nontoxic, readily available, cost-effective, environmentally friendly, and can be used as a model for the self-sufficient chemical recycling of PET via glycolysis.

17.
Am J Chin Med ; 51(5): 1085-1104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37385964

RESUMEN

Ginseng is a very commonly used natural product in the world, and its two main species are Asian ginseng and American ginseng. Ginseng is an adaptogenic botanical that reportedly protects the body against stress, stabilizes physiological processes, and restores homeostasis. Previously, different animal models and contemporary research methodologies have been used to reveal ginseng's biomedical activities in different body systems and the linked mechanisms of actions. However, human clinical observation data on ginseng effects have attracted more attention from the general public and medical community. In this paper, after an introduction of the phytochemistry of ginseng species, we review positive ginseng clinical studies, mainly conducted in developed countries, performed over the past 20 years. The reported effects of ginseng are presented in several sections, and conditions impacted by ginseng include diabetes; cardiovascular disorders; cognition, memory, and mood; the common cold and flu; cancer fatigue and well-being; quality of life and social functioning, etc. Administration of ginseng demonstrated a good safety record in humans. Although encouraging beneficial effects obtained from clinical data, using the study treatment regimen, the reported ginseng effects in general only ranged from mild to moderate. Nonetheless, these beneficial effects of ginseng could be a valuable add-on therapy for patients receiving standard drug treatments. Additionally, as a dietary supplement, ginseng possesses an important role in maintaining and promoting human health. We believe that the quality of future ginseng trials should be improved, particularly by providing detailed herbal phytochemistry and quality control information. With solid effectiveness data obtained from a well-designed, carefully executed ginseng clinical trial, this meritoriously herbal medicine will be widely used by consumers and patients.


Asunto(s)
Medicamentos Herbarios Chinos , Ginsenósidos , Panax , Animales , Humanos , Fitoterapia , Calidad de Vida , Ginsenósidos/farmacología
18.
Clin Case Rep ; 11(2): e6993, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36852126

RESUMEN

Idiopathic spinal subdural hematoma (SSDH) is a rare phenomenon. Here, we present a 16-year-old-boy who presented with acute sudden onset weakness and brown squared syndrome; the cervical MRI findings showed acute subdural hematoma from C2 to C6. Emergent surgical intervention was performed, and significant improvement was seen in follow-ups.

19.
Talanta ; 224: 121895, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33379103

RESUMEN

Hydrogels are 3D polymeric networks with great swelling capability in water and appropriate chemical, mechanical and biological features which make it feasible to maintain bioactive substances. Herein, we fabricated carbon dots-chitosan nanocomposite hydrogels via reacting carbon dots synthesized from various aldehyde precursors with chitosan after that functionalized with ssDNA probe for detection of microRNA-21 in MCF-7 cancer cells. More importantly, three fluorescent hydrogels were produced using schiff base reaction (forming imine bonds) among the amine in chitosan and aldehyde groups on the CDs surface. Furthermore, the hydrogel films, CDs and CDs-chitosan nanocomposite hydrogels were characterized by UV-vis absorption and fluorescence spectra, FT-IR, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The DNA hydrogel bioassay strategy revealed a great stability and a superb sensitivity for microRNA-21, with a suitable linear range (0.1-125 fM) and a detection limit (0.03 fM). For sample analysis, the biosensors exhibited good linearity with MCF-7 cancer cell concentrations from 1000 to 25000, 1000-25000 and 1000-6000 cells mL-1 and detection limit of 310, 364 and 552 cells mL-1, for glutaraldehyde, nitrobezaldehyde and benzaldehyde based nanocomposite hydrogels, respectively. In addition, cell viability consequences demonstrated low probe cytotoxicity, so nanocomposite hydrogels was utilized to multicolor imaging of MCF-7 cancer cells.


Asunto(s)
Neoplasias de la Mama , Quitosano , MicroARNs , Puntos Cuánticos , Neoplasias de la Mama/genética , Carbono , Humanos , Hidrogeles , MicroARNs/genética , Espectroscopía Infrarroja por Transformada de Fourier
20.
Int J Dev Neurosci ; 81(3): 221-228, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33570815

RESUMEN

Autism Spectrum Disorders (ASDs) are common neurodevelopmental disorders with a growing incidence that generally present in the first 3 years of life. Behavioral symptoms, including impaired social interaction and increased repetitive or stereotypic movements, are hallmark characteristics of autism. Animal models are research tools used to study the biology of the disease and to develop new therapeutic approaches. The complexity of the etiology of autism makes it challenging to develop a comprehensive animal model that accurately mimics different clinical aspects of autism. Here, we reviewed the literature on modeling and behavioral assessment of autism in the rodent, and focused on ASD behavioral phenotypes that can be modeled in rodents. These animal models can be effective in gaining a better understanding of the pathophysiology of the disease.


Asunto(s)
Trastorno Autístico/genética , Conducta Animal , Modelos Teóricos , Animales , Modelos Animales de Enfermedad , Roedores
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