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1.
MethodsX ; 12: 102712, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38660038

RESUMO

Sulfate is the fourth most abundant anion in circulation. Despite being an essential nutrient for healthy growth and development, sulfate is not routinely measured in clinical settings. In research settings, animal studies have shown that hyposulfatemia and hypersulfaturia are associated with adverse developmental outcomes. Those findings have increased interest in measuring plasma and urine sulfate levels. In this study, we describe a modified assay to measure sulfate in low volumes of plasma and urine. •A streamlined microassay to measure sulfate levels using a microtiter plate format was developed.•To determine the robustness of the assay, this method assessed reagent stability and concentrations, as well as absorbance at different wavelengths and following a range of incubation times.•The optimized microassay was used to measure sulfate level in pig plasma and urine samples, which were compared to a validated ion chromatography method.

2.
Pharmacol Res ; 197: 106948, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37806602

RESUMO

The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major steps of the immune-inflammatory processes, such as tumor necrosis factor, interleukins or integrins. Nevertheless, these molecules have not yet met expectations regarding efficacy and safety, resulting in a significant percentage of refractory or relapsing patients. Thus, novel treatment options are urgently needed. The minor isoform of the complement inhibitor C4b-binding protein, C4BP(ß-), has been shown to confer a robust anti-inflammatory and immunomodulatory phenotype over inflammatory myeloid cells. Here we show that C4BP(ß-)-mediated immunomodulation can significantly attenuate the histopathological traits and preserve the intestinal epithelial integrity in dextran sulfate sodium (DSS)-induced murine colitis. C4BP(ß-) downregulated inflammatory transcripts, notably those related to neutrophil activity, mitigated circulating inflammatory effector cytokines and chemokines such as CXCL13, key in generating ectopic lymphoid structures, and, overall, prevented inflammatory immune cell infiltration in the colon of colitic mice. PRP6-HO7, a recombinant curtailed analogue with only immunomodulatory activity, achieved a similar outcome as C4BP(ß-), indicating that the therapeutic effect is not due to the complement inhibitory activity. Furthermore, both C4BP(ß-) and PRP6-HO7 significantly reduced, with comparable efficacy, the intrinsic and TLR-induced inflammatory markers in myeloid cells from both ulcerative colitis and Crohn's disease patients, regardless of their medication. Thus, the pleiotropic anti-inflammatory and immunomodulatory activity of PRP6-HO7, able to "reprogram" myeloid cells from the complex inflammatory bowel environment and to restore immune homeostasis, might constitute a promising therapeutic option for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Humanos , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Imunomodulação , Inflamação , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Células Mieloides
3.
Redox Biol ; 64: 102770, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37295159

RESUMO

It is unclear whether mitochondrial dysfunction and redox stress contribute to impaired age-related muscle regenerative capacity. Here we characterized a novel compound, BI4500, that inhibits the release of reactive oxygen species (ROS) from the quinone site in mitochondrial complex I (site IQ). We tested the hypothesis that ROS release from site IQ contributes to impaired regenerative capacity in aging muscle. Electron transfer system site-specific ROS production was measured in adult and aged mouse isolated muscle mitochondria and permeabilized gastrocnemius fibers. BI4500 inhibited ROS production from site IQ in a concentration-dependent manner (IC50 = âˆ¼985 nM) by inhibiting ROS release without impairing complex I-linked respiration. In vivo BI4500 treatment decreased ROS production from site IQ. Muscle injury and sham injury were induced using barium chloride or vehicle injection to the tibialis anterior (TA) muscle in adult and aged male mice. On the same day as injury, mice began a daily gavage of 30 mg/kg BI4500 (BI) or placebo (PLA). Muscle regeneration (H&E, Sirius Red, Pax7) was measured at 5 and 35 days after injury. Muscle injury increased centrally nucleated fibers (CNFs) and fibrosis with no treatment or age effect. There was a significant age by treatment interaction for CNFs at 5- and 35-days post injury with significantly more CNFs in BI adults compared to PLA adults. Muscle fiber cross-sectional area (CSA) recovered significantly more in adult BI mice (-89 ± 365 µm2) compared to old PLA (-599 ± 153 µm2) and old BI (-535 ± 222 µm2, mean ± SD). In situ TA force recovery was measured 35 days after injury and was not significantly different by age or treatment. Inhibition of site IQ ROS partially improves muscle regeneration in adult but not old muscle demonstrating a role for CI ROS in the response to muscle injury. Site IQ ROS does not contribute to impaired regenerative capacity in aging.


Assuntos
Mitocôndrias Musculares , Músculo Esquelético , Camundongos , Masculino , Animais , Espécies Reativas de Oxigênio/farmacologia , Envelhecimento/fisiologia , Poliésteres/farmacologia
4.
Chinese Critical Care Medicine ; (12): 274-277, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-992016

RESUMO

Objective:To explore whether barium chloride (BaCl 2) preconditioning has the protective effect on lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) model in mice and the possible mechanism. Methods:Sixty 8-12 week old healthy C57BL/6 male mice were randomly divided into control group, ARDS model group and BaCl 2 pretreatment group, with 20 mice in each group. The BaCl 2 pretreatment group was continuously injected with BaCl 2 (4 mg/kg through the tail vein) for 3 days before ARDS model establishment. ARDS model was established by intratracheally injecting (3 mg/kg) LPS. The control group was intratracheally given the same volume of 0.9% normal saline. On 24th hour after ARDS model establishment, some mice were sacrificed for obtaining fresh lung tissue. And the right lower lobe of the lung was separated for observing the pathological changes of lung tissue while the left lung tissue was used to measure the wet/dry weight ratio (W/D) of the lung. Some mice were sacrificed for observing pulmonary microvascular permeability at 2nd hours after injecting Evans blue (EB) through tail vein. The left mice were killed for alveolar lavage to measure the levels of tumor necrosis factor-α (TNF-α) via enzyme linked immunosorbent assay (ELISA). Results:Comparing with the control group, ARDS model group showed typical ARDS pathological changes, which included the increased W/D ratio (4.951±0.161 vs. 3.449±0.299, P < 0.01) and the content of EB in the lung tissue (μg/g: 0.130±0.027 vs. 0.085±0.011, P < 0.01), the damaged alveolar wall structure, lung congestion and exudates in the alveoli, as well as amounts of inflammatory cells. The pathological score of lung injury (10.33±1.15 vs. 1.67±0.58) and the level of TNF-α in BALF (ng/L: 900.85±247.80 vs. 68.21±5.79) were significantly increased in the ARDS model group (both P < 0.01). Comparing with the ARDS model group, the lung W/D ratio (4.620±0.125 vs. 4.951±0.161) and the EB content in the lung tissue (μg/g: 0.108±0.011 vs. 0.130±0.027) of BaCl 2 pretreatment group were significantly reduced (both P < 0.01). And the damaged pulmonary structural BaCl 2 pretreatment group were significantly alleviated. In addition, the pulmonary pathological score (5.00±1.00 vs. 10.33±1.15) and the level of TNF-α in BALF (ng/L: 169.16±73.33 vs. 900.85±247.80) were significantly decreased (both P < 0.01). Conclusion:Barium chloride pretreatment can improve the lung histopathological changes of ARDS model mice induced by LPS by reducing the permeability of pulmonary capillaries and local inflammatory reaction.Barium chloride has the protective effect against LPS attack in mice model of ARDS.

5.
IBRO Neurosci Rep ; 13: 344-355, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274789

RESUMO

Introduction: slowly adapting mechanoreceptors in the skin provide vital tactile information to animals. The ionic channels that underlie their functioning is the subject of intense research. Previous work suggests that potassium channels may play particular roles in the activation and firing of these mechanoreceptors. Objective: We used a range of potassium channel blockers and openers to observe their effects on different phases of mechanoreceptor responses. Methods: Extracellular recording of neural activity of slowly adapting mechanoreceptors was carried out in an in vitro preparation of the sinus hair follicles taken from rat whisker pads. A range of potassium (K+) channel modulators were tested on these mechanoreceptor responses. The channel blockers tested were: tetraethylammonium (TEA), barium chloride (BaCl2), dequalinium, 4-aminopyridine (4-AP), paxilline, XE 991, apamin, and charybdotoxin. Results: Except for charybdotoxin and apamin, these drugs increased the activity of both types of slowly adapting units, St I and St II. Generally, both spontaneous and evoked (dynamic and static) activities increased. The channel opener NS1619 was also tested. NS1619 clearly decreased evoked activity (both dynamic and static) while leaving spontaneous activity relatively unaffected, with no clear discrimination of effects on the two types of St receptor. Conclusion: These findings are consistent with the targets of the drugs suggesting that K+ channels play an important role in the maintenance of spontaneous firing and in the production of and persistence of mechanoreceptor activity.

6.
Carbohydr Polym ; 294: 119786, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868796

RESUMO

The main objective of this work is to prepare completely biodegradable macrocapsules containing organic phase change materials (PCMs) for thermal energy storage applications. Three different PCMs hexadecane (paraffin), butyl stearate (ester) and caprylic acid (fatty acid) were encapsulated inside barium crosslinked pectin shell using ionic gelation method. Millimeter size(≤2 mm) pectin-PCM capsules were prepared with highest encapsulation efficiency of 83.66 wt% (H5), 83.21 wt% (B5) and 84.39 wt% (C5) containing hexadecane, butyl stearate and caprylic acid respectively as core, while corresponding melting enthalpies were 184.89 kJ kg-1 (H5), 116 kJ kg-1 (B5) and 118 kJ kg-1 (C5). Pectin encapsulation improved thermal stability of PCM-capsules by 70 °C-130 °C compared to core PCMs. 25 g of H5, B5 and C5 capsules provided thermal buffering of 62 min, 50 min and 51mins respectively during discharge experiments. Thus, the prepared biodegradable pectin-PCM capsules are effective for thermal energy storage.


Assuntos
Temperatura Alta , Polissacarídeos , Cápsulas , Pectinas , Termodinâmica
7.
Anal Bioanal Chem ; 414(6): 2163-2179, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35066601

RESUMO

The stable isotope ratios of sulfur (δ34S relative to Vienna Cañon Diablo Troilite) in sulfates and sulfides determined by elemental analysis and isotope ratio mass spectrometry (EA/IRMS) have been proven to be a remarkable tool for studies of the (bio)geochemical sulfur cycles in modern and ancient environments. However, the use of EA/IRMS to measure δ34S in arsenides and sulfarsenides may not be straightforward. This difficulty can lead to potential health and environmental hazards in the workplace and analytical problems such as instrument contamination, memory effects, and a non-matrix-matched standardization of δ34S measurements with suitable reference materials. To overcome these practical and analytical challenges, we developed a procedure for sulfur isotope analysis of arsenides, which can also be safely used for EA/IRMS analysis of arsenic sulfides (i.e., realgar, orpiment, arsenopyrite, and arsenian pyrite), and mercury sulfides (cinnabar). The sulfur dioxide produced from off-line EA combustion was trapped in an aqueous barium chloride solution in a leak-free system and precipitated as barium sulfate after quantitative oxidation of hydrogen sulfite by hydrogen peroxide. The derived barium sulfate was analyzed by conventional EA/IRMS, which bracketed the δ34S values of the samples with three international sulfate reference materials. The protocol (BaSO4-EA/IRMS) was validated by analyses of reference materials and laboratory standards of sulfate and sulfides and achieved accuracy and precision comparable with those of direct EA/IRMS. The δ34S values determined by BaSO4-EA/IRMS in sulfides (arsenopyrite, arsenic, and mercury sulfides) samples from different origins were comparable to those obtained by EA/IRMS, and no sulfur isotope fractionations were introduced during sample preparation. We report the first sulfur isotope data of arsenides obtained by BaSO4-EA/IRMS.

8.
Materials (Basel) ; 14(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34947196

RESUMO

A new approach based on the atomization of non-Newtonian fluids has been proposed to produce microparticles for a potential inhalation route. In particular, different solutions of alginate were atomized on baths of different crosslinkers, piperazine and barium chloride, obtaining microparticles around 5 and 40 microns, respectively. These results were explained as a consequence of the different viscoelastic properties, since oscillatory analysis indicated that the formed hydrogel beads with barium chloride had a higher storage modulus (1000 Pa) than the piperazine ones (20 Pa). Pressure ratio (polymer solution-air) was identified as a key factor, and it should be from 0.85 to 1.00 to ensure a successful atomization, obtaining the smallest particle size at intermediate pressures. Finally, a numerical study based on dimensionless numbers was performed to predict particle size depending on the conditions. These results highlight that it is possible to control the microparticles size by modifying either the viscoelasticity of the hydrogel or the experimental conditions of atomization. Some experimental conditions (using piperazine) reduce the particle size up to 5 microns and therefore allow their use by aerosol inhalation.

9.
J Vet Res ; 64(4): 567-571, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33367146

RESUMO

INTRODUCTION: Early detection of pregnancy is vital for appropriate reproductive management programmes to facilitate the rapid re-insemination of non-pregnant females and reduce the calving interval. MATERIAL AND METHODS: A barium chloride test was compared with a commercial progesterone ELISA to detect pregnancy in non-descriptive cows and investigate if it could be applied as an alternative to ELISA in the field. Blood and urine samples were collected from 74 cows with recorded insemination dates. The progesterone ELISA and barium chloride assay were implemented to detect progesterone (P4) in blood and urine specimens, respectively. The cows' reproductive systems were examined after they were slaughtered to determine the uterus's status. Macroscopic examination of the uterus was used as a reference standard for both tests. RESULTS: The sensitivity rates of the P4 ELISA and barium chloride test to detect pregnant cows were 100.0% and 79.4%, and to detect the corpus luteum (CL) were 83.0% and 87.0%, respectively, their sensitivity increasing in the presence of the CL. The ELISA and barium chloride tests were 79.7% and 52.7% accurate in the diagnosis of pregnancy. The accuracy of the barium chloride test in CL detection increased to 81.0%, and that of the ELISA to 86.4%. There were no significant differences (P = 0.052) between the barium chloride assay and ELISA when they were utilised for the identification of the CL. CONCLUSION: The barium chloride test can be an inexpensive and time-saving alternative to ELISA in pregnancy diagnosis when the insemination date is known.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32631824

RESUMO

Bacterial membrane potential is difficult to measure using classical electrophysiology techniques due to the small cell size and the presence of the peptidoglycan cell wall. Instead, chemical probes are often used to study membrane potential changes under conditions of interest. Many of these probes are fluorescent molecules that accumulate in a charge-dependent manner, and the resulting fluorescence change can be analyzed via flow cytometry or using a fluorescence microplate reader. Although this technique works well in many Gram-positive bacteria, it generates fairly low signal-to-noise ratios in Gram-negative bacteria due to dye exclusion by the outer membrane. We detail an optimized workflow that uses the membrane potential probe, 3,3'-diethyloxacarbocyanine iodide [DiOC2(3)], to measure Escherichia coli membrane potential changes in high throughput and describe the assay conditions that generate significant signal-to-noise ratios to detect membrane potential changes using a fluorescence microplate reader. A valinomycin calibration curve demonstrates this approach can robustly report membrane potentials over at least an ∼144-mV range with an accuracy of ∼12 mV. As a proof of concept, we used this approach to characterize the effects of some commercially available small molecules known to elicit membrane potential changes in other systems, increasing the repertoire of compounds known to perturb E. coli membrane energetics. One compound, the eukaryotic Ca2+ channel blocker amlodipine, was found to alter E. coli membrane potential and decrease the MIC of kanamycin, further supporting the value of this screening approach. This detailed methodology permits studying E. coli membrane potential changes quickly and reliably at the population level.


Assuntos
Bioensaio , Escherichia coli , Potenciais da Membrana , Bactérias Gram-Negativas , Valinomicina
11.
Food Res Int ; 130: 108966, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156400

RESUMO

In this work, coated liposome as a novel delivery system assembled from genipin-crosslinked with whey protein isolate (WPI) and sodium alginate (SA) as the second layer on WPI-coated liposomal was developed in order to increase its bioavailability and prolong release for drug and nutraceuticals. Therefore, the influence of GP and SA on physico-chemical properties, long term stability and in vitro release behavior of WPI coated nanoliposomes (NLs) for encapsulation of flaxseed oil were investigated successively. Compared with WPI-NLs and uncoated NLs, GP-WPI-NLs and SA-WPI-NLs displayed more significant changes in average diameter, zeta potential, entrapment efficiency, morphology, FT-IR, thermal properties, with lower n-3 fatty acids released. In terms of physical and oxidative stability during storage at 45 °C for 30 days, the GP was remarkably more effective than the SA. The results suggested that the coating with SA and cross-linking with GP altered the surface properties, and provided more chemical stability for the flaxseed oil as core material.


Assuntos
Alginatos/química , Iridoides/química , Óleo de Semente do Linho/química , Lipossomos/química , Proteínas do Soro do Leite/química , Reatores Biológicos , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
12.
Life Sci ; 250: 117586, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222464

RESUMO

AIM: The inward rectifier K+ (Kir) channels and prostanoids are important factors in regulating vascular tone, but the relationship between them has not been well studied. We aimed to study the involvement of prostanoids in regulating Kir activity in the rat intrarenal arteries (RIRAs). MAIN METHODS: The vascular tone of isolated RIRAs was recorded with a wire myograph. The intracellular Ca2+ concentrations ([Ca2+]i) and Kir currents were measured with a Ca2+-sensitive fluorescence probe and patch clamp, respectively, in the arterial smooth muscle cell (ASMC) freshly isolated from RIRAs. Kir2.1 expression in RIRAs was assayed by Western blotting. KEY FINDINGS: At 0.03-1.0 mM, BaCl2 (a specific Kir blocker) concentration-dependently contracted RIRAs and elevated [Ca2+]i levels. Mild stimulations with various vasoconstrictors at low concentrations significantly potentiated RIRA contraction induced by Kir closure with BaCl2. In both the quiescent and the stimulated RIRAs, cyclooxygenase inhibition and thromboxane-prostanoid receptor (TPR) antagonism depressed BaCl2-induced RIRA contraction, while nitric oxide (NO) synthetase inhibition and endothelium-denudation enhanced the contraction. Kir2.1 expression was significantly more abundant in smaller RIRAs. Ba2+-sensitive Kir currents were depressed by TPR agonist U46619 while increased by NO donor sodium nitroprusside. SIGNIFICANCE: The present results reveal that vasoconstrictor stimulation augments RIRA contraction induced by Kir closure with Ba+ and indicate that prostanoid synthesis followed by TPR activation is involved in the modulation of the myocyte Kir activity. This study suggests that prostanoid synthesis and TPR may be potential targets for dysfunctions in renal blood circulation.


Assuntos
Miócitos de Músculo Liso/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Prostaglandinas/metabolismo , Artéria Renal/citologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Animais , Artérias/metabolismo , Cálcio/metabolismo , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Rim/irrigação sanguínea , Masculino , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Receptores de Prostaglandina/metabolismo , Tromboxanos/metabolismo , Vasoconstritores/farmacologia
13.
Am J Respir Cell Mol Biol ; 62(2): 217-230, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31461300

RESUMO

Skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease negatively impacts quality of life and survival. Cigarette smoking (CS) is the major risk factor for chronic obstructive pulmonary disease and skeletal muscle dysfunction; however, how CS affects skeletal muscle function remains enigmatic. To examine the impact of CS on skeletal muscle inflammation and regeneration, male BALB/c mice were exposed to CS for 8 weeks before muscle injury was induced by barium chloride injection, and were maintained on the CS protocol for up to 21 days after injury. Barium chloride injection resulted in architectural damage to the tibialis anterior muscle, resulting in a decrease contractile function, which was worsened by CS exposure. CS exposure caused muscle atrophy (reduction in gross weight and myofiber cross-sectional area) and altered fiber type composition (31% reduction of oxidative fibers). Both contractile function and loss in myofiber cross-sectional area by CS exposure gradually recovered over time. Satellite cells are muscle stem cells that confer skeletal muscle the plasticity to adapt to changing demands. CS exposure blunted Pax7+ centralized nuclei within satellite cells and thus prevented the activation of these muscle stem cells. Finally, CS triggered muscle inflammation; in particular, there was an exacerbated recruitment of F4/80+ monocytic cells to the site of injury along with enhanced proinflammatory cytokine expression. In conclusion, CS exposure amplified the local inflammatory response at the site of skeletal muscle injury, and this was associated with impaired satellite cell activation, leading to a worsened muscle injury and contractile function without detectable impacts on the recovery outcomes.


Assuntos
Fumar Cigarros/efeitos adversos , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Regeneração/fisiologia , Animais , Masculino , Camundongos Endogâmicos BALB C , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Doenças Musculares/metabolismo , Fator de Transcrição PAX7/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Qualidade de Vida , Fumar/fisiopatologia
14.
Ann Geriatr Med Res ; 23(2): 83-89, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32743293

RESUMO

Skeletal muscle regeneration in mice has traditionally been studied using local freeze burn or snake venom injection models. More recently, a barium chloride (BaCl2)-induced muscle injury model has been established and is gaining popularity due to the relatively simple procedure and accessibility to required reagents. Here we sought to characterize the local and systemic effects of BaCl2-induced muscle injury. For this study, a 1.2% BaCl2 solution was locally administered to the tibialis anterior (TA) muscle and local and systemic phenotypes were analyzed at different timepoints. When 50 µL of the solution was injected unilaterally in the TA muscle, no mortality was observed. However, when 100 µL of the solution was injected, 50% of the mice died within 24 h. Serum analysis of the mice injected with 50 µL of BaCl2 solution at days 1 and 7 revealed changes resembling rhabdomyolysis. At day 1 post-injection of 50 µL of the BaCl2 solution, acute suppurative inflammation was observed in gross examination of the TA muscle, while extensive hemorrhagic necrosis was revealed on histological examination. At day 7, regenerated myofibers with centralized nuclei appeared with the resolution of acute inflammatory infiltration and the muscle tissue displayed molecular signatures consistent with myofiber differentiation. The overall muscle injury and regeneration phenotypes in the BaCl2-induced muscle injury model were similar to those of the well-established freeze burn or snake venom injection models. Taken together, the BaCl2-induced muscle injury model is comparable to conventional muscle injury and regeneration models, with considerations for possible systemic effects.

15.
J Biomater Sci Polym Ed ; 29(10): 1126-1154, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29376775

RESUMO

Three dimensional (3D) bioplotting requires appropriate crosslinkers to crosslink the hydrogel precursor while simultaneously maintaining the viability of embedded cells. However, the evaluation and comparison of various types of crosslinkers in bioplotting remains underexplored to date. This paper presents our study of the influence of three ionic crosslinkers-calcium chloride (CaCl2), barium chloride (BaCl2), and zinc chloride (ZnCl2)-on the mechanical and biological properties of 3D bioplotted alginate scaffolds. The scaffold mechanical properties characterized included the elastic modulus, swelling, and degradation while the biological properties considered included Schwann cell viability and surface morphology. The mechanical and biological properties of the bioplotted scaffolds were both dependent on the crosslinkers used for fabrication; specifically, crosslinking ions resulted in the elastic modulus of the hydrogels decreasing in the order BaCl2>CaCl2>ZnCl2 over 42 days while Schwann cell viability decreased in the order CaCl2>BaCl2>ZnCl2 over 7 days. Taken together, these results offer insights that are effective in terms of manipulating the 3D bioplotting process so as to tune and optimize the mechanical and biological performance of the plotted scaffolds for tissue engineering applications.


Assuntos
Cátions Bivalentes/química , Reagentes de Ligações Cruzadas/química , Hidrogéis/química , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais/química , Alginatos/química , Animais , Bário/química , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Cálcio/química , Sobrevivência Celular , Células Cultivadas , Módulo de Elasticidade , Ratos , Células de Schwann/citologia , Zinco/química
16.
Arch Physiol Biochem ; 124(3): 237-246, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29072102

RESUMO

CONTEXT: Barium (Ba) may induce oxidative stress leading to tissues injury. OBJECTIVE: Our study investigated the therapeutic efficiency of zinc (Zn) and selenium (Se) against neurotoxicity induced by Ba in adult rats and their progeny. MATERIAL AND METHODS: Pregnant rats are exposed either to Ba (67 ppm), Ba + Zn, Ba + S or to only Zn and Se. RESULTS: In Ba-treated rats, there was an increase of MDA, H2O2, AOPP levels and SOD activity in the cerebellum of dams and their pups, a decrease in GPx, CAT, AChE, Na+K+-ATPase and Mg2+-ATPase activities, GSH and NPSH levels. These changes were confirmed by histological damages. Co-administration of Zn or Se to Ba-treated rats ameliorated the biochemical and histological aspects. CONCLUSION: Our results revealed that Zn and Se have shown promising effects against Ba toxicity in the cerebellum of adult rats and their suckling pups.


Assuntos
Adenosina Trifosfatases/metabolismo , Bário/efeitos adversos , Membrana Celular/metabolismo , Cerebelo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Zinco/farmacologia , Acetilcolinesterase/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Cerebelo/citologia , Cerebelo/metabolismo , Relação Dose-Resposta a Droga , Feminino , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar
17.
Carbohydr Polym ; 181: 760-767, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29254033

RESUMO

Motivated by the extensive application of agar, this work developed a wet-spinning process to fabricate micro-scale fibers using the gelation process of agar. The effect of three vital spinning parameters, namely dope concentration, coagulation bath composition, and fiber post-processing on morphological properties, tensile properties and chemical structure of the fiber have been discussed. The concentration of agar was determined by the results of rheological measurement. The addition of barium chloride in the coagulation process improved the mechanical properties of fibers as compared to deionized water as coagulation. The agar fibers immersed in amino silicone demonstrated significantly showed better mechanical properties compared to the agar fibers only immersed in ethanol. The physical and chemical properties of agar fibers were characterized by X-ray diffraction, FTIR, tensile testing, and SEM. The results showed that excellent agar fibers with several potential applications can be produced with amino silicone modification in optimum coagulation bath.

18.
Immunopharmacol Immunotoxicol ; 40(1): 18-24, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29094617

RESUMO

This study investigated the effects of BaCl2 adsorbed to polyethylene glycol (PEG) microspheres on human blood mononuclear cells (MN) co-cultured with breast cancer cell lines (MCF-7). The MCF-7 cells were obtained from the American Type Culture Collection and the blood mononuclear (MN) cells from volunteer donors. MN cells, MCF-7 cells and their co-culture (MN and MCF-7 cells) were pre-incubated for 24 h with or without 25 and 1000 pg L-1 BaCl2 (Ba25 and Ba1000), PEG microspheres or 25 and 1000 pg L-1 BaCl2 adsorbed to PEG microspheres (PEG-Ba25 and PEG-Ba1000). Rheological parameters and apoptosis were determined. Fluorescence microscopy and flow cytometry analyses revealed that BaCl2 was able to adsorb the PEG microspheres. The blood flow and viscosity curves were similar among the treatments. In general, apoptosis rates increased in co-cultured cells, co-cultured cells incubated with Ba25 and with PEG-Ba25, but the highest rates were observed in co-cultured cells incubated with PEG-Ba1000. In conclusion, BaCl2 adsorbed to PEG microspheres exhibited dose-dependent antitumor effects against human MCF-7 breast cancer cells co-cultured with MN cells, thereby offering a possible therapeutic alternative for treating this disease provided they are administered at very low concentrations.


Assuntos
Antineoplásicos , Compostos de Bário , Neoplasias da Mama , Cloretos , Leucócitos Mononucleares/metabolismo , Microesferas , Polietilenoglicóis , Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos de Bário/química , Compostos de Bário/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Cloretos/química , Cloretos/farmacologia , Feminino , Humanos , Leucócitos Mononucleares/patologia , Células MCF-7 , Masculino , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia
19.
Environ Sci Pollut Res Int ; 24(34): 26634-26645, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28956246

RESUMO

The present study was designed to investigate the hematotoxicity, sero-biochemical and histological changes due to the accumulation of BaCl2 and BaCO3, the most important barium salts in our daily lives, in different soft tissues including the liver, kidney, heart, and spleen of adult rats after an oral exposure for 30 consecutive days, and to explain the different mechanisms by which this metal can exert these impacts. For this purpose, adult male rats were divided into three main groups of 15 animals each: group I, serving as controls, group II, receiving BaCl2 orally in a dose of 179 mg barium/kg b.wt, and group III, receiving BaCO3 orally in a dose of 418 mg barium/kg b.wt. for 30 consecutive days. Obviously, normocytic normochromic anemia was evident in both barium groups. Serum biochemical analysis revealed significant declines in glutathione peroxidase, catalase, superoxide dismutase, and urea with significant elevations in malondialdehyde, lactate dehydrogenase, and creatine kinase levels. Hyperphosphatemia, hypokalemia, hypocalcemia, and hypochloremia were also evident in both barium groups. Besides, residual analysis of both barium salts in different body organs revealed significantly abundant barium residues in the liver, spleen, heart, and kidney, respectively in both barium salts groups. Moreover, splenic tissue showed hemosiderosis, peritubular congestion, and necrotic glomeruli with intratubular hemorrhage. Sever subepicardial congestion with intramuscular edema was evident in the heart. In conclusion, BaCl2 and BaCO3 were able to deliver mortalities, antioxidant enzymes exhaustion, and a sort of normocytic normochromic anemia, as well as marked disturbances in cardiac, hepatic, and renal functions due to the accumulation of these two salts in the soft tissues. Therefore, these results demonstrate the unrecognized toxicity of those two barium salts due to their accumulation in various soft tissues of the body and so, this needs to reconsider about barium exposure.


Assuntos
Anemia/induzido quimicamente , Compostos de Bário/toxicidade , Bário/toxicidade , Carbonatos/toxicidade , Cloretos/toxicidade , Rim/metabolismo , Fígado/metabolismo , Miocárdio/metabolismo , Anemia/sangue , Anemia/enzimologia , Animais , Antioxidantes/metabolismo , Bário/farmacocinética , Compostos de Bário/farmacocinética , Carbonatos/farmacocinética , Cloretos/farmacocinética , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
20.
Toxicol Mech Methods ; 27(9): 677-686, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28683652

RESUMO

Nowadays, liver diseases constitute a major health problem in the world. The objective of the present study was to elucidate the hepatotoxicity induced by barium chloride (BaCl2) administered at graded doses in order to evaluate redox state and membrane-bound ATPases in the liver of adult rats. Our results showed, after 21 days of treatment with barium at doses 67 150 and 300 ppm, an increase in hepatic biomarkers such as AST, ALT and GGT activities and in bilirubin and albumin levels. A significant increase in MDA, LOOHs, H2O2, AOPP and PCO levels in liver of treated rats with graded doses of BaCl2 was also observed suggesting the implication of oxidative stress with a significant relation between dose and response. Moreover, LDH activity increased in plasma and decreased in liver of all treated groups. Antioxidant activities of glutathione peroxidase and catalase decreased, especially with the highest dose of barium, indicating a failure of antioxidant system defense. Additionally, the activities of Na+K+-ATPase and Mg2+-ATPase significantly decreased in all treated groups. Our biochemical findings were supported by histological observations. These results highlight the subchronic hepatotoxicity of barium.


Assuntos
Adenosina Trifosfatases/metabolismo , Compostos de Bário/toxicidade , Cloretos/toxicidade , Fígado/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Animais , Compostos de Bário/administração & dosagem , Cloretos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Peróxido de Hidrogênio/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Metalotioneína/metabolismo , Oxirredução , Ratos , Ratos Wistar
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