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1.
Clin Transl Sci ; 17(5): e13821, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38742709

RESUMO

Inflammatory bowel disease (IBD) is characterized by a chronically dysregulated immune response in the gastrointestinal tract. Bone marrow multipotent mesenchymal stromal cells have an important immunomodulatory function and support regeneration of inflamed tissue by secretion of soluble factors as well as through direct local differentiation. CXCR4 is the receptor for CXCL12 (SDF-1, stromal-derived factor-1) and has been shown to be the main chemokine receptor, required for homing of MSCs. Increased expression of CXCL12 by inflamed intestinal tissue causes constitutive inflammation by attracting lymphocytes but can also be used to direct MSCs to sites of injury/inflammation. Trypsin is typically used to dissociate MSCs into single-cell suspensions but has also been shown to digest surface CXCR4. Here, we assessed the regenerative effects of CXCR4high and CXCR4low MSCs in an immune-deficient mouse model of DSS-induced colitis. We found that transplantation of MSCs resulted in clinical improvement and histological recovery of intestinal epithelium. In contrary to our expectations, the levels of CXCR4 on transplanted MSCs did not affect their regenerative supporting potential, indicating that paracrine effects of MSCs may be largely responsible for their regenerative/protective effects.


Assuntos
Colite , Mucosa Intestinal , Células-Tronco Mesenquimais , Receptores CXCR4 , Regeneração , Animais , Camundongos , Células da Medula Óssea/metabolismo , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Colite/induzido quimicamente , Colite/patologia , Modelos Animais de Doenças , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Receptores CXCR4/metabolismo , Receptores CXCR4/genética
2.
Chem Biodivers ; 20(3): e202201124, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36730100

RESUMO

Bee bread is a unique natural product made by bees and good for human health. It has many bioactive molecules that can treat or prevent diseases. In this study, melissopalynological methods were used to examine five bee bread samples. Major plant sources found in bee bread were Lotus spp., Trifolium spp., and Xeranthemum spp., which are from the Fabaceae and Asteraceae families. Then, the amount of phenolic compounds and major carotenoids in bee bread (BB) samples were quantified. Gallic acid, caffeic acid, quercetin, and kaempferol were found in all BB samples, with ß-carotene being the most abundant carotenoid in all but BB1. In addition, the total phenolic/flavonoid content and antioxidant activities of all BB samples were determined. Total flavonoid, total phenolic, DPPH⋅, and ABTS⋅+ values were varied between 5.6-10.00 mg GAE/g DW, 1.2-4.3 mg QE/g DW, 1.2-5.5 mg TEAC/g DW, and 2.6-15.4 mg TEAC/g DW, respectively.


Assuntos
Antioxidantes , Própole , Animais , Humanos , Antioxidantes/farmacologia , Asteraceae/química , Abelhas/química , Abelhas/metabolismo , Carotenoides/química , Carotenoides/farmacologia , Flavonoides , Fenóis/química , Fenóis/farmacologia , Própole/química
3.
Biol Trace Elem Res ; 201(3): 1488-1502, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35362937

RESUMO

Honeybee pollens are good food sources in terms of their mineral contents and are specific to the regions they are collected. In addition, they may be used as bioindicators in the assessment of environmental pollution based on their potentially toxic element contents. In the present study, mineral element composition and potentially toxic element levels of honeybee pollen samples collected from various cities in East Black Sea Region of Turkey (18 samples) were determined by inductively coupled plasma mass spectrometry (ICP-MS) after microwave assisted acid digestion. The method validation was performed by using CRM (Certified Reference Material-BCR®279-Sea Lettuce-Ulva lactuca) to evaluate the accuracy and precision. Elemental composition of honeybee pollens were detected within the following ranges (minimum-maximum, mg kg-1 dry pollen); Mn (manganese): 11.579-117.349, Fe (Iron): 34.865-811.043, Zn (zinc): 17.707-56.223, Se (selenium): 0.422-0.722, Cr (chromium): 0.848-6.949, Cu (copper): 7.510-26.344, Mg (magnesium): 549.921-2149.716, Ca (calcium): 726.575-2201.837, Na (sodium): 36.518-120.283, Pb (lead): < 0.005-0.622, Cd (cadmium): 0.039-1.390, Ni (nickel): 2.317-21.710, and As (arsenic): 1.331-2.248. Recommended daily allowance, target hazard quotients, hazard index, and carcinogenic risk values of the pollens were calculated with the help of these results. In considering THQ values, pollens were determined to be safe for the consumption of both genders. Based on the carcinogenic risk calculation, most of the pollens examined in this study were categorized as moderately risky. Monitoring studies can be used to identify new sources of contamination or the origin and spread of a particular element. Hence, bee pollens can also be considered as potential bioindicators of toxic metal pollution. HIGHLIGHTS: • Mineral content and potentially toxic metal levels of 18 honeybee pollens were determined. • Recommended daily allowance (RDA) values were calculated. • The nutritional aspects of honeybee pollen samples were evaluated. • Hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR) estimation of honeybee pollens were assessed. • The potentiality of honeybee pollens as a bioindicator for pollution was discussed.


Assuntos
Biomarcadores Ambientais , Metais Pesados , Abelhas , Feminino , Masculino , Animais , Turquia , Mar Negro , Análise Espectral , Ferro/análise , Pólen/química , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco
4.
Environ Sci Pollut Res Int ; 29(24): 36161-36169, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35060036

RESUMO

In this study, pollens were collected from 25 different locations of Northern Turkey to investigate pollution monitoring. Surface chemistry of pollen samples was characterized by X-ray photoelectron spectroscopy (XPS). Then the concentrations of certain elements (Li, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Ba, and Pb) in pollen samples were determined by inductively coupled plasma mass spectrometry (ICP-MS) for the evaluation of environmental pollution. The levels of elements were detected in the following ranges (minimum-maximum, mg/kg dry pollen): Li (0.18-0.39), Al (24.98-308.04), V (6.18-98.58), Cr (1.05-6.81), Mn (13.85-95.91), Fe (52.20-326.26), Co (0.15-0.34), Ni (1.66-10.79), Cu (8.61-19.01), Zn (20.47-70.02), As (1.22-2.65), Se (0.39-0.67), Cd (0.05-0.74), Ba (0.73-16.30), and Pb (0.00-0.26). It has been concluded that there is a correlation between the pollen samples with high heavy metal concentrations and traffic density as these regions are closer to the road in the northern region. It is exposed to pollution from various sources such as intensified urbanization and tourism activities carried out on land and sea; industrial activities are increasing rapidly due to the opportunities offered by the coastal areas, sea transportation, and agricultural, domestic, and industrial pollution coming from the inner regions through rivers and streams. In this sense, pollens can be used as potential bio-indicators for monitoring heavy metal pollution and gives an idea about how we can use them for future assessing purposes.


Assuntos
Biomarcadores Ambientais , Metais Pesados , Animais , Abelhas , Cádmio/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Chumbo/análise , Metais Pesados/análise , Espectroscopia Fotoeletrônica , Pólen/química , Medição de Risco , Turquia
5.
World J Stem Cells ; 13(9): 1197-1214, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34630858

RESUMO

Despite a vast amount of different methods, protocols and cryoprotective agents (CPA), stem cells are often frozen using standard protocols that have been optimized for use with cell lines, rather than with stem cells. Relatively few comparative studies have been performed to assess the effects of cryopreservation methods on these stem cells. Dimethyl sulfoxide (DMSO) has been a key agent for the development of cryobiology and has been used universally for cryopreservation. However, the use of DMSO has been associated with in vitro and in vivo toxicity and has been shown to affect many cellular processes due to changes in DNA methylation and dysregulation of gene expression. Despite studies showing that DMSO may affect cell characteristics, DMSO remains the CPA of choice, both in a research setting and in the clinics. However, numerous alternatives to DMSO have been shown to hold promise for use as a CPA and include albumin, trehalose, sucrose, ethylene glycol, polyethylene glycol and many more. Here, we will discuss the use, advantages and disadvantages of these CPAs for cryopreservation of different types of stem cells, including hematopoietic stem cells, mesenchymal stromal/stem cells and induced pluripotent stem cells.

7.
Turk J Chem ; 45(1): 60-70, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679153

RESUMO

This paper includes the results of the first study about the phenolic characteristics and antimicrobial analyses of Geranium ibericum subsp. jubatum species found in Turkey . In the present work, the phenolic contents of different parts of the G. ibericum (flower, root, leaf) were determined with high-performance liquid chromatography (HPLC)-DAD (diode-array detector) and liquid chromatography (LC)-MS/MS (mass spectrometry). The following phenolic compounds were investigated: catechin, protocatechuic acid, gallic acid, ellagic acid, chlorogenic acid, 4-hydroxybenzaldehyde, p -coumaric acid, rutin, naringenin, kaempferol . Based on the results obtained, the roots and flowers of the plant are found to be very rich in ellagic acid (3473.57 µg g-1 dry plant) and catechin (2228.76 µg g-1 dry plant). The amount of chlorogenic acid (54.570 µg g-1 dry plant) is also high in the roots. The amounts of protocatechuic acid (122.5 µg g-1 dry plant) and gallic acid (725.34 µg g-1 dry plant) are high in the leaves. In addition, the total extract of G. ibericum obtained from leaf, flower, and root was tested against 6 gram-negative bacteria and Candida albicans . The G. ibericum extract was nearly as effective as commercial antibiotics at some concentrations (500-750 µg µL-1) for Acinetobacter baumannii , Klebsiella pneumonia , Proteus mirabilis , and Bacillus cereus .

8.
J Chromatogr Sci ; 59(6): 491-501, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33634307

RESUMO

Investigation of phenolic content from different pine bark species grown in Turkey was performed using a reversed-phase high pressure liquid chromatography with ultraviolet (RP-HPLC-UV) method. All phenolic constituents were separated in <26 min on reversed-phase C18 column with gradient mobile phase that consists of orthophosphoric acid, methanol and acetonitrile. Detections were made on an UV detector at 280 nm and at a flow rate of 1 mL/min. Samples were prepared according to Masqueller's conventional sample preparation method with slight modifications. To avoid the reduction in extraction efficiency the sample preparation step was carried out under argon atmosphere. The linearity of the method was between 0.9994 and 0.9999. The detection limits for the five phenolic constituents ranged from 0122 to 0.324 mg/L. Catechin and taxifolin were found in all pine barks at a concentration of 0.065 ± 0.002-1.454 ± 0.004 and 0.015 ± 0.001-23.164 ± 0.322 mg/g, respectively. Epicatechin was determined in four pine barks between 0.027 ± 0.001 and 0.076 ± 0.002 mg/g, ferulic acid in two pine barks between 0.010 ± 0.001 and 0.022 ± 0.001 mg/g and epicatechin gallate in only one of the pine barks at 0.025 ± 0.001 mg/g. Finally, the total amount of phenolic compounds and antioxidant capacities of the pine barks were found to be very high.


Assuntos
Fenóis/análise , Pinus/química , Casca de Planta/química , Catequina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Quercetina/análogos & derivados , Quercetina/análise , Espectrometria de Massas em Tandem/métodos
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