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1.
BMC Endocr Disord ; 23(1): 182, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641049

RESUMO

BACKGROUND: Understanding pharmacokinetics (PK) and pharmacodynamics (PD) of the sustained-release liothyronine (SR-T3) is of paramount importance to design therapeutic regimens that are able to simulate normal thyroid hormone secretion while avoiding excursions in the T3 serum concentration. Here, we designed a parallel randomized clinical trial to characterize the PK and PD of the combined preparations of LT4 + SR-T3 in hypothyroid patients. METHODS: Radioiodine-treated hypothyroid patients over 20 years of age, who attained euthyroidism with LT4 monotherapy were recruited from the Endocrine Clinic in Tehran. The patients were allocated to two intervention groups of group A: 9 µg SR-T3 plus 68.5 µg LT4 (ratio 1:7.5) and group B: 12 µg SR-T3 plus 60 µg LT4 (ratio 1:5), and a control group with LT4 monotherapy. For PD study, thyroid hormone profile was evaluated at 8 and 12 weeks intervals after intervention. To assess PK properties of SR-T3, T3-Cmax, T3-Tmax and AUC0 - 24 were calculated at the last visit. RESULTS: Serum T4 and FT4 concentrations decreased in the intervention groups after 3 months. No significant difference was observed in serum T3 and FT3 concentrations before and after intervention. Serum T3/T4 ratio increased significantly in the intervention groups after intervention, with the highest increase in group B from 8.6 ± 2.03 at baseline to 12.2 ± 1.6. Comparison of trial groups at follow-up showed no differences in serum TSH, T4, T3 and T3/T4 concentrations among different groups. During 24 h, minimal variation in serum T3 concentration was observed in group B with mean ∆T3 of 15.4 ± 10.5 ng/dl. T3-Tmax, T3-Cmax and AUC0 - 24 in the combined sustained-release preparation were 4.38 ± 1.1 h., 101.0 ± 5.7 ng/dl and 2257 ± 110 ng.h/L, respectively which were significantly different from the control group. CONCLUSION: Combined treatment with a single dose of SR-T3 plus LT4 is associated with increased serum T3/T4 ratio and minimal excursions in serum T3 concentration during 24 h; however, it was not significantly different from the control group. To incorporate sustained-release T3 in the management of hypothyroidism, a higher ratio of SR-T3 to LT4 than that of the previously recommended by the international organizations is suggested. IRCT REGISTRATION NUMBER: IRCT20100922004794N13. https://www.irct.ir/search/result?query=IRCT20100922004794N13 . Registration date: 08/12/2021.


Assuntos
Hipotireoidismo , Tri-Iodotironina , Humanos , Adulto , Tiroxina , Preparações de Ação Retardada , Radioisótopos do Iodo , Irã (Geográfico) , Hipotireoidismo/tratamento farmacológico
2.
Avicenna J Phytomed ; 12(2): 155-162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35614885

RESUMO

Objective: Atopic dermatitis (AD) is a common skin disorder with symptoms including severe pruritus and eczematous lesions. AD affects between 5 and 20% of people in their life. Silymarin (SM) is a polyphenolic flavonoid from Silybum marianum L. and has several therapeutic characteristics including antiallergic, anticancer, and anti-inflammatory properties. Fumaria officinalis is a small plant that has a high antioxidant power and modulating effects on the immune system. Therefore, the current study intended to examine the influence of these two herbs extract on severity and symptoms of AD in patients. Materials and Methods: 40 patients with mild to moderate eczema randomly received mometasone 0.1% or the herbal cream. Treatment course was 2 weeks and patients were examined before and after 2 weeks of treatment using the SCORAD system. Results: The reduction of SCORAD score was significant in both groups (p=0.04 in the herbal group and p=0.03 in the mometasone group) but no significant difference was observed between the groups. Mean SCORAD score was 27.66±5.9 before therapy and 4.77±1.6 after therapy in the mometasone group and mean SCORAD score was 26.05±7.1 before therapy and 6.944±2.6 after therapy in the herbal group. Conclusion: The current study indicated the impact of these two herbs extract on severity and symptoms of AD in patients; these plants may be a new treatment in reducing eczema symptoms and its problems.

3.
J Acoust Soc Am ; 151(3): 1490, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35364905

RESUMO

Functional grading is a distinctive feature adopted by nature to improve the transition between tissues that present a strong mismatch in mechanical properties, a relevant example being the tendon-to-bone attachment. Recent progress in multi-material additive manufacturing now allows for the design and fabrication of bioinspired functionally graded soft-to-hard composites. Nevertheless, this emerging technology depends on several design variables, including both material and mechanistic ingredients, that are likely to affect the mechanical performance of such composites. In this paper, a model-based approach is developed to describe the interaction of ultrasound waves with homogeneous and heterogeneous additively manufactured samples, which respectively display a variation either of the material ingredients (e.g., ratio of the elementary constituents) or of their spatial arrangement (e.g., functional gradients, damage). Measurements are performed using longitudinal bulk waves, which are launched and detected using a linear transducer array. First, model is calibrated by exploiting the signals measured on the homogeneous samples, which allow identifying relationships between the model parameters and the material composition. Second, the model is validated by comparing the signals measured on the heterogeneous samples with those predicted numerically. Overall, the reported results pave the way for characterizing and optimizing multi-material systems that display complex bioinspired features.


Assuntos
Osso e Ossos , Ultrassonografia
4.
Food Chem ; 371: 130997, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537611

RESUMO

In this study, we report the synthesis and application of a nanocomposite comprising metal-organic framework MIL-101(Cr) and graphene nanopowder (GNP) as a promising sorbent for the extraction of organophosphorus pesticides (OPPs) in juices, water, vegetables and honey samples. A syringe filter, for the first time, was used to host the synthesized nanocomposite and extract the OPPs followed by GC-MS analysis. Different characterization methods including XRD, FTIR, TGA, BET and SEM were employed to confirm the formation of studied nanocomposite. The results indicated that the GNP/MIL-101(Cr) could provide higher capacity for adsorption of OPPs and lower detection limit compared to pristine MIL-101(Cr). The detection limits were 0.005 to 15.0 µg/Kg and the linear range found between 0.05 and 400 µg/Kg. The proposed method showed very good repeatability with the RSD values ranging from 2.9% to 7.1%. The recoveries were between 84% -110% with the spiked levels of 2.0-100.0 µg/Kg.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Praguicidas , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Compostos Organofosforados/análise , Praguicidas/análise , Extração em Fase Sólida , Seringas
5.
Mikrochim Acta ; 187(12): 647, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33165626

RESUMO

A novel aluminum terephthalate/Fe2O3 nanocomposite was synthesized by the addition of Fe2O3 nanoparticles into a reaction solution containing aluminum terephthalate MOF. The synthesized nanocomposite was successfully used as a fiber coating material for solid-phase microextraction (SPME) of six organophosphorus compounds (OPPs) from river water, grape juice, and tea samples. The effect of different parameters on the efficiency of SPME including desorption temperature and time, extraction temperature and time, salt concentration, pH, and agitation were thoroughly studied. The OPPs were detected and determined using GC-MS. According to the findings, a wide linear range (0.15-800 µg kg-1), low limit of detection (0.04-10 µg kg-1), and high recoveries from spiked samples (87.5-112%) were achieved with low inter-day relative standard deviation (3.2-6.7%, n = 5). The MIL-53(Al)/Fe2O3 nanocomposite showed  a high extraction ability towards OPPs, and hence, it can be considered a promising adsorbent for the extraction of various pesticides in complex matrices like tea and juice.Graphical abstract.


Assuntos
Compostos de Alumínio/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Compostos Organofosforados/análise , Praguicidas/análise , Ácidos Ftálicos/química , Limite de Detecção , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos
6.
J Sep Sci ; 42(18): 3002-3008, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31294510

RESUMO

Electromembrane extraction was used with high-performance liquid chromatography for preconcentration and determination of ampicillin residues in cow milk. Ampicillin is transferred from an aqueous solution through a thin layer containing octan-1-ol, silver nanoparticles, and reduced graphene oxide which serves as a supported liquid membrane. Inside the fiber impregnated with supported liquid membrane mixture was filled 10 µL of an acceptor phase. Experimental parameters were optimized for extraction efficiency of ampicillin. Under the optimized conditions, the proposed method provided acceptable linear range (2-100 µg/L), satisfactory repeatability (RSD% < 7.1), low limit of detection (0.6 µg/L), and a high enrichment factor (295) corresponding to extraction recovery of 37%. Consequently, the proposed method was successfully applied for the determination of ampicillin residues in different cow milks.


Assuntos
Ampicilina/análise , Microextração em Fase Líquida , Animais , Cromatografia Líquida de Alta Pressão , Nanopartículas Metálicas/química , Leite/química , Prata/química
7.
Vet Res Forum ; 8(4): 353-359, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29326796

RESUMO

The aim of this study was to evaluate the effects of dietary vitamin E on reproductive and productive parameters in Japanese quails. A total number of 240 female and 80 male Japanese quail were divided into five treatments with four replications in a completely randomized design. Experimental diets were zero control, 30, 60, 120 and 240 mg kg-1 of vitamin E. Fertility and total hatchability were not affected by treatments. But, the lowest hatch of fertile eggs and the highest embryonic death were observed in control group (p < 0.05). Left testes weight in T2 and T4 was higher than control (p < 0.05). Right testes weight and sera FSH concentration in males were not affected by treatments. The highest testosterone concentration of males was observed in T5 (p < 0.05). Weight and length of oviduct as well as weight of ovary and FSH concentration in females did not affected by treatments. Estrogen concentration in T4 treatment was greater than control (p < 0.05). Most of the egg characteristics were not affected by treatments. However, higher egg mass and production rates were observed in T2 and T3groups than control group (p < 0.05). Feed intake and conversion ratio did not differ among treatments. In conclusion, dietary vitamin E improved hatch of fertile egg, embryonic viability, egg mass and production rates in Japanese quail. The effect of dietary vitamin E combined with selenium on these characteristics are recommended for future study in Japanese quail.

8.
Food Chem ; 212: 65-71, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27374507

RESUMO

In this study, for the first time electromembrane extraction (EME) was used as a highly efficient sample pre-treatment method for the UV-VIS spectrophotometric determination of As(V) in water samples. The influences of experimental parameters during EME were investigated and optimized using one-variable-at-a-time methodology as follows: organic solvent: 1-octanol+2.5% (V/V) di-(2-ethylhexyl) phosphate, applied voltage: 70V, extraction time: 15min, pH of acceptor: 13, stirring rate: 750rpm. The method allowed the determination of As(V) in the range of 5-300ngmL(-1). The relative standard deviation was found to be within the range of 3.4-7.6%. The limit of detection, corresponding to a signal to noise ratio of three, was 1.5ngmL(-1). The proposed method was finally applied to the determination of As(V) in water samples and relative recoveries ranging from 95 to 102% were obtained.


Assuntos
Arsênio/análise , Espectrofotometria/métodos , 1-Octanol , Membranas Artificiais , Compostos Orgânicos , Solventes
9.
Talanta ; 136: 190-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25703002

RESUMO

Differentiation of animal sources of gelatin is required for many reasons such as some anxieties about bovine spongiform encephalopathy or a ban on consuming porcine gelatin in some religions. In the present work, an efficient method is introduced for determination of animal origin of gelatin samples. The basis of this procedure is the application of pulsed electric field for extraction, preconcentration, and analysis of derivatized amino acids in gelatin. To this end, after derivatization of amino acids of interest by means of o-phthalaldehyde (OPA) for enhancing their ultraviolet (UV) absorbance as well as increasing their lipophilicities, a 137V electric field was applied for 20min with 10min(-1) frequency to make the analytes migrate through a 200µm organic liquid membrane into an aqueous acceptor phase. Finally, the acceptor phase was analyzed by HPLC-UV. The proposed technique offered a high efficiency for analysis of amino acids, regarding 43% and 79% as extraction recoveries and 25ng mL(-1) and 50ng mL(-1) as limits of detection (LODs) for asparagine and glutamine, respectively. Therefore, due to sample cleanup ability of the proposed method and obtained preconcentration factors (29 and 53 for asparagine and glutamine, respectively), it could be carried out for differentiation of animal origins of gelatin samples, even if only small amounts of samples are available or in complicated media of foodstuffs and medicament.


Assuntos
Asparagina/análise , Gelatina/química , Glutamina/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Suínos , o-Ftalaldeído/química
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