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1.
The resistance of metal–organic frameworks towards water is a very critical issue concerning their practical use. Recently, it was shown for microporous MOFs that the water stability could be increased by introducing hydrophobic pendant groups. Here, we demonstrate a remarkable stabilisation of the mesoporous MOF Al‐MIL‐101‐NH2 by postsynthetic modification with phenyl isocyanate. In this process 86 % of the amino groups were converted into phenylurea units. As a consequence, the long‐term stability of Al‐MIL‐101‐URPh in liquid water could be extended beyond a week. In water saturated atmospheres Al‐MIL‐101‐URPh decomposed at least 12‐times slower than the unfunctionalised analogue. To study the underlying processes both materials were characterised by Ar, N2 and H2O sorption measurements, powder X‐ray diffraction, thermogravimetric and chemical analysis as well as solid‐state NMR and IR spectroscopy. Postsynthetic modification decreased the BET equivalent surface area from 3363 to 1555 m2 g?1 for Al‐MIL‐101‐URPh and reduced the mean diameters of the mesopores by 0.6 nm without degrading the structure significantly and reducing thermal stability. In spite of similar water uptake capacities, the relative humidity‐dependent uptake of Al‐MIL‐101‐URPh is slowed and occurs at higher relative humidity values. In combination with 1H‐27Al D ‐HMQC NMR spectroscopy experiments this favours a shielding mechanism of the Al clusters by the pendant phenyl groups and rules out pore blocking.  相似文献   

2.
This study investigated the effects of low‐level laser therapy (LLLT) in the liver function, structure and inflammation in a experimental model of carbon tetrachloride (CCl4)‐induced liver cirrhosis. Wistar rats were divided into Control, LLLT, CCl4 and CCl4+LLLT groups. CCl4 groups received CCl4 (0.4 g kg?1; i.p.), three times a week, for 12 weeks. A 830 nm LLLT was performed with a continuous wave, 35 mW, 2.5 J cm?2 per point, applied to four points of the liver (right and left upper and lower extremities, in the four lobes of the liver) for 2 weeks. Liver structure and inflammation (cirrhotic areas, collagen deposition, inflammation, density of Kupffer and hepatic stellate cells) and function (aspartate aminotransferase, alkaline phosphatase, gamma glutamyltransferase, lactate dehydrogenase, total proteins and globulins) were evaluated. LLLT significantly reduced CCl4‐increased aspartate aminotransferase (P < 0.001), alkaline phosphatase (P < 0.001), gamma‐glutamyl transferase (P < 0.001) and lactate dehydrogenase (P < 0.01) activity, as well as total proteins (P < 0.05) and globulins (P < 0.01). LLLT also reduced the number of cirrhotic areas, the collagen accumulation and the hepatic inflammatory infiltrate. Of note, LLLT reduced CCl4‐increased number of Kupffer cells (P < 0.05) and hepatic stellate cells (P < 0.05). We conclude that LLLT presents beneficial effects on liver function and structure in an experimental model of CCl4‐induced cirrhosis.  相似文献   

3.
Inflammation is involved in many human pathologies, including osteoarthritis (OA). Hydrogen (H2) is known to have anti‐inflammatory effects; however, the bioavailability of directly administered H2 gas is typically poor. Herein, a local delivery system that can provide a high therapeutic concentration of gaseous H2 at inflamed tissues is proposed. The delivery system comprises poly(lactic‐co‐glycolic acid) microparticles that contain magnesium powder (Mg@PLGA MPs). Mg@PLGA MPs that are intra‐muscularly injected close to the OA knee in a mouse model can act as an in situ depot that can evolve gaseous H2 continuously, mediated by the cycle of passivation/activation of Mg in body fluids, at a concentration that exceeds its therapeutic threshold. The analytical data that are obtained in the biochemical and histological studies indicate that the proposed Mg@PLGA MPs can effectively mitigate tissue inflammation and prevent cartilage from destruction, arresting the progression of OA changes.  相似文献   

4.
Pharmacological therapy is widely used in the treatment of muscle injuries. On the other hand, low‐level laser therapy (LLLT) arises as a promising nonpharmacological treatment. The aim of this study was to analyze the effects of sodium diclofenac (topical application) and LLLT on morphological aspects and gene expression of biochemical inflammatory markers. We performed a single trauma in tibialis anterior muscle of rats. After 1 h, animals were treated with sodium diclofenac (11.6 mg g‐1 of solution) or LLLT (810 nm; continuous mode; 100 mW; 3.57 W cm?2; 1, 3 or 9 J; 10, 30 or 90 s). Histological analysis and quantification of gene expression (real‐time polymerase chain reaction—RT‐PCR) of cyclooxygenase 1 and 2 (COX‐1 and COX‐2) and tumor necrosis factor‐alpha (TNF‐α) were performed at 6, 12 and 24 h after trauma. LLLT with all doses improved morphological aspects of muscle tissue, showing better results than injury and diclofenac groups. All LLLT doses also decreased (< 0.05) COX‐2 compared to injury group at all time points, and to diclofenac group at 24 h after trauma. In addition, LLLT decreased (< 0.05) TNF‐α compared both to injury and diclofenac groups at all time points. LLLT mainly with dose of 9 J is better than topical application of diclofenac in acute inflammation after muscle trauma.  相似文献   

5.
One inescapable feature of life on the earth is exposure to ionizing radiation. The thyroid gland is one of the most sensitive organs to gamma‐radiation and endocrine disrupters. Low‐level laser therapy (LLLT) has been used to stimulate tissue repair, and reduce inflammation. The aim of this study was to gauge the value of using Helium–Neon laser to repair the damaged tissues of thyroid gland after gamma‐irradiation. Albino rats were used in this study (144 rats), divided into control, gamma, laser, and gamma plus laser‐irradiated groups, each group was divided into six subgroups according to time of treatment (total six sessions). Rats were irradiated once with gamma radiation (6 Gy), and an external dose of laser (Wavelength 632.8 nm, 12 mW, CW, Illuminated area 5.73 cm2, 2.1 mW cm?2, 120 s, 1.4 J, 0.252 J cm?2) twice weekly localized on thyroid region of the neck, for a total of six sessions. Animals were sacrificed after each session. Analysis included thyroid function, oxidative stress markers, liver function and blood picture. Results revealed improvement in thyroid function, liver function and antioxidant levels, and the blood cells count after LLLT.  相似文献   

6.
This study evaluated the effects of LLLT on the expression of inflammatory cytokines related to the development of oral mucositis by gingival fibroblasts. Primary gingival fibroblasts were seeded on 24‐well plates (105 cells/well) for 24 h. Fresh serum‐free culture medium (DMEM) was then added, and cells were placed in contact with LPS (Escherichia coli, 1 μg mL?1), followed by LLLT irradiation (LaserTABLE—InGaAsP diode prototype—780 nm, 25 mW) delivering 0, 0.5, 1.5 or 3 J cm?². Cells without contact with LPS were also irradiated with the same energy densities. Gene expression of TNF‐α, IL‐1β, IL‐6 and IL‐8 was evaluated by Real‐Time PCR, and protein synthesis of these cytokines was determined by enzyme‐linked immunosorbent (ELISA) assay. Data were statistically analyzed by the Kruskal–Wallis test, complemented by the Mann–Whitney test (< 0.05). LPS treatment increased the gene expression and protein synthesis of TNF‐α, IL‐6 and IL‐8, while the expression of IL‐1β was not affected. For LPS‐treated groups, LLLT promoted significant decreases in the expression of TNF‐α, IL‐6, and IL‐8 at 1.5 J cm?2 and 3 J cm?2. These results demonstrate that LLLT promoted a beneficial biomodulatory effect on the expression of inflammatory cytokines related to oral mucositis by human gingival fibroblasts.  相似文献   

7.
A nanostructured organic–inorganic framework, hexagonal NH2‐MIL‐88B, has been prepared through a facile one‐pot reflux reaction and then it was characterized using various techniques. The as‐prepared sample with high specific surface area (414 m2 g?1) showed excellent adsorption for 2,4,6‐trinitrophenol (TNP) in the liquid phase. Detailed studies of the adsorption kinetics, adsorption mechanism, adsorption isotherm, activation energy and various thermodynamic parameters were conducted. The adsorption mechanism of NH2‐MIL‐88B for TNP may be ascribed to hydrogen bond interaction, and the complexation between ─OH in TNP and unsaturated Fe(III) on the surface of NH2‐MIL‐88B. The maximum adsorption capacity of NH2‐MIL‐88B for TNP based on the Langmuir isotherm was 163.66 mg g?1. The as‐prepared NH2‐MIL‐88B adsorbent seems to be a promising material in practice for TNP removal from aqueous solution.  相似文献   

8.
Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. To clarify the mechanisms of action of PBM at cellular and organism levels, we investigated its effect on Paramecium primaurelia (Protozoa) irradiated by an 808 nm infrared diode laser with a flat‐top handpiece (1 W in CW). Our results led to the conclusion that: (1) the 808 nm laser stimulates the P. primaurelia without a thermal effect, (2) the laser effect is demonstrated by an increase in swimming speed and in food vacuole formation, (3) the laser treatment affects endogenous adenosine triphosphate (ATP) production in a positive way, (4) the effects of irradiation dose suggest an optimum exposure time of 50 s (64 J cm?2 of fluence) to stimulate the Paramecium cells; irradiation of 25 s shows no effect or only mild effects and irradiation up to 100 s does not increase the effect observed with 50 s of treatment, (5) the increment of endogenous ATP concentration highlights the positive photobiomodulating effect of the 808 nm laser and the optimal irradiation conditions by the flat‐top handpiece.  相似文献   

9.
The aim of this study was to determine the anti-osteoarthritic effects of LI73014F2, which consists of Terminalia chebula fruit, Curcuma longa rhizome, and Boswellia serrata gum resin in a 2:1:2 ratio, in the monosodium iodoacetate (MIA)-induced osteoarthritis (OA) rat model. LI73014F2 was orally administered once per day for three weeks. Weight-bearing distribution and arthritis index (AI) were measured once per week to confirm the OA symptoms. Synovial membrane, proteoglycan layer, and cartilage damage were investigated by histological examination, while synovial fluid interleukin-1β level was analyzed using a commercial kit. Levels of pro-inflammatory mediators/cytokines and matrix metalloproteinases (MMPs) in the cartilage tissues were investigated to confirm the anti-osteoarthritic effects of LI73014F2. LI73014F2 significantly inhibited the MIA-induced increase in OA symptoms, synovial fluid cytokine, cartilage damage, and expression levels of pro-inflammatory mediators/cytokines and MMPs in the articular cartilage. These results suggest that LI73014F2 exerts anti-osteoarthritic effects by regulating inflammatory cytokines and MMPs in MIA-induced OA rats.  相似文献   

10.
Osteoarthritis (OA) is an age-related joint disease that is characterized by degeneration of articular cartilage and chronic pain. Oxidative stress is considered one of the pathophysiological factors in the progression of OA. We investigated the effects of grape seed proanthocyanidin extract (GSPE), which is an antioxidant, on monosodium iodoacetate (MIA)-induced arthritis of the knee joint of rat, which is an animal model of human OA. GSPE (100 mg/kg or 300 mg/kg) or saline was given orally three times per week for 4 weeks after the MIA injection. Pain was measured using the paw withdrawal latency (PWL), the paw withdrawal threshold (PWT) and the hind limb weight bearing ability. Joint damage was assessed using histological and microscopic analysis and microcomputerized tomography. Matrix metalloproteinase-13 (MMP13) and nitrotyrosine were detected using immunohistochemistry. Administration of GSPE to the MIA-treated rats significantly increased the PWL and PWT and this resulted in recovery of hind paw weight distribution (P < 0.05). GSPE reduced the loss of chondrocytes and proteoglycan, the production of MMP13, nitrotyrosine and IL-1β and the formation of osteophytes, and it reduced the number of subchondral bone fractures in the MIA-treated rats. These results indicate that GSPE is antinociceptive and it is protective against joint damage in the MIA-treated rat model of OA. GSPE could open up novel avenues for the treatment of OA.  相似文献   

11.
Metal‐organic frameworks consisting of amino‐modified MIL‐101(M: Cr, Al, and Fe) crystals have been synthesized and subsequently incorporated to glycidyl methacrylate monoliths to develop novel stationary phases for nano‐liquid chromatography. Two incorporation approaches of these materials in monoliths were explored. The metal‐organic framework materials were firstly attached to the pore surface through reaction of epoxy groups present in the parent glycidyl methacrylate‐based monolith. Alternatively, NH2‐MIL‐101(M) were admixed in the polymerization mixture. Using short time UV‐initiated polymerization, monolithic beds with homogenously dispersed metal‐organic frameworks were obtained. The chromatographic performance of embedded UV‐initiated composites was demonstrated with separations of polycyclic aromatic hydrocarbons and non‐steroidal anti‐inflammatory drugs as test solutes. In particular, the incorporation of the NH2‐MIL‐101(Al) into the organic polymer monoliths led to an increase in the retention of all the analytes compared to the parent monolith. The hybrid monolithic columns also exhibited satisfactory run‐to‐run and column‐to‐column reproducibility.  相似文献   

12.
The tight skin mouse (Tsk?/+) is a model of scleroderma characterized by impaired vasoreactivity, increased oxidative stress, attenuated angiogenic response to VEGF and production of the angiogenesis inhibitor angiostatin. Low‐level light therapy (LLLT) stimulates angiogenesis in myocardial infarction and chemotherapy‐induced mucositis. We hypothesize that repetitive LLLT restores vessel growth in the ischemic hindlimb of Tsk?/+ mice by attenuating angiostatin and enhancing angiomotin effects in vivo. C57Bl/6J and Tsk?/+ mice underwent ligation of the femoral artery. Relative blood flow to the foot was measured using a laser Doppler imager. Tsk?/+ mice received LLLT (670 nm, 50 mW cm?2, 30 J cm?2) for 10 min per day for 14 days. Vascular density was determined using lycopersicom lectin staining. Immunofluorescent labeling, Western blot analysis and immunoprecipitation were used to determine angiostatin and angiomotin expression. Recovery of blood flow to the ischemic limb was reduced in Tsk?/+ compared with C57Bl/6 mice 2 weeks after surgery. LLLT treatment of Tsk?/+ mice restored blood flow to levels observed in C57Bl/6 mice. Vascular density was decreased, angiostatin expression was enhanced and angiomotin depressed in the ischemic hindlimb of Tsk?/+ mice. LLLT treatment reversed these abnormalities. LLLT stimulates angiogenesis by increasing angiomotin and decreasing angiostatin expression in the ischemic hindlimb of Tsk?/+ mice.  相似文献   

13.
In this study, we aimed to analyze the effects of low‐level laser therapy (LLLT; 660 nm) on levels of protein expression of inflammatory mediators after cutting Achilles tendon of rats. Thirty Wistar male rats underwent partial incisions of the left Achilles tendon, and were divided into three groups of 10 animals according to the time of euthanasia after injury: 6, 24 and 72 h. Each group was then divided into control group and LLLT group (treated with 100 mW, 3.57 W cm?2, 0.028 cm2, 214 J cm?2, 6 J, 60 s, single point). In LLLT group, animals were treated once time per day until the time of euthanasia established for each group. The group treated with LLLT showed a significant reduction of IL‐1β compared with control groups at three time points (6 h: P = 0.0401; 24 h: P = 0.0015; 72 h: P = 0.0463). The analysis of IL‐6 showed significant reduction only in the LLLT group at 72 h compared with control group (P = 0.0179), whereas IL‐10 showed a significant increase in the treated group compared with control group at three experimental times (6 h: P = 0.0007; 24 h: P = 0.0256; 72 h: P < 0.0001). We conclude that LLLT is an important modulator of inflammatory cytokines release after injury in Achilles tendon.  相似文献   

14.
A metal–organic framework material, MIL‐125(Ti), was solvothermally prepared and characterized using X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and surface area measurements. MIL‐125(Ti) was then used as an adsorbent for Rhodamine B (RhB) removal in aqueous solution. The adsorption kinetics, adsorption mechanism, adsorption isotherm, activation energy and various thermodynamic parameters were studied in detail. The maximum adsorption capacity of MIL‐125(Ti) for RhB was 59.92 mg g?1. MIL‐125(Ti) appears to be a promising material for RhB adsorption from aqueous solutions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

15.
Ultraviolet B (UVB) irradiation is one of the most dangerous insults for skin and causes sunburn, erythema, photoaging and photocarcinogenesis. Curcumin (diferuloylmethane), a yellow spice derived from dried rhizomes of Curcuma longa, has been shown to possess significant anti‐inflammatory, antioxidant, anticarcinogenic, antimutagenic, anticoagulant and anti‐infective effects. However, the protective effects of curcumin against acute photo‐damage are poorly understood. In this study, we investigated the photoprotective effects of curcumin against UVB‐induced acute photo‐damage in hairless mice and immortalized human keratinocytes (HaCaT). Topical application of curcumin significantly inhibited acute UVB (540 mJ cm?2, for 3 successive days)‐induced inflammatory cells, collagen accrementition derangement and lipid peroxidation, and effectively induced NF‐E2‐related factor 2 (Nrf2) nuclear accumulation in uncovered (Uncv) hairless mice skin. Treatment of HaCaT cells with curcumin significantly attenuated acute UVB (300 mJ cm?2)‐induced lactate dehydrogenase release, intracellular reactive oxygen species production and DNA damage, activated the expression of the phase II detoxifying enzymes and promoted DNA repair activity. The photoprotective effect provided by curcumin was potential associated with modulation of Nrf2‐dependent antioxidant response. Our study suggested that curcumin is a potential agent for preventing and/or treating UV radiation‐induced acute inflammation and photoaging.  相似文献   

16.
A facile and efficient strategy is developed to modify aptamers on the surface of the magnetic metal‐organic framework MIL‐101 for the rapid magnetic solid‐phase extraction of ochratoxin A. To the best of our knowledge, this is the first attempt to create a robust aptamer‐modified magnetic MIL‐101 with covalent bonding for the magnetic separation and enrichment of ochratoxin A. The saturated adsorption of ochratoxin A by aptamer‐modified magnetic MIL‐101 was 7.9 times greater than that by magnetic metal‐organic framework MIL‐101 due to the former's high selective recognition as well as good stability. It could be used for extraction more than 12 times with no significant changes in the extraction efficiency. An aptamer‐modified magnetic MIL‐101‐based method of magnetic solid‐phase extraction combined with ultra high performance liquid chromatography with tandem mass spectrometry was developed for the determination of trace ochratoxin A with limit of detection of 0.067 ng/L. Ochratoxin A of 4.53–13.7 ng/kg was determined in corn and peanut samples. The recoveries were in the range 82.8–108% with a relative standard deviation (n = 5) of 4.5–6.5%. These results show that aptamer‐modified magnetic MIL‐101 exhibits selective and effective enrichment performance and have excellent potential for the analysis of ultra‐trace targets from complex matrices.  相似文献   

17.
Alpinia officinarum is used for its anti‐inflammatory activity historically in China. Diarylheptanoids isolated from A. officinarum play important biological roles in the prevention and treatment of inflammatory disorders. Seven diarylheptanoids (1–7) were isolated from A. officinarum. The cell viabilities and anti‐inflammatory activities of diarylheptanoids were evaluated by MTT assay and tumor necrosis factor‐α production in Kdo2‐lipid A‐stimulated RAW 264.7 cells in vitro. The relationships between their anti‐inflammatories and structure‐activities are discussed. The results indicated that compounds 1 and 3–7 had significant anti‐inflammatory activities. The relationships between inflammation and phospholipids metabolism were elucidated by multivariate data analysis. Twenty‐two potential biomarkers were identified in inflammatory group vs. blank group, and 11 potential biomarkers were identified for inflammatory group vs. drug‐treatment groups. Ten common phospholipids were characterized. On the basis of a previous study in our laboratory, we found that phosphatidylethanolamine (18:0/18:1) might be the important glycerophospholipid biomarker in inflammation. In this study, we firstly combined anti‐inflammatory activities and glycerophospholipids changes of traditional Chinese medicine. This work suggests that the anti‐inflammatory activities of diarylheptanoids might be significantly related to glycerophospholipids and could provide a useful database for investigating the anti‐inflammatory effects of traditional Chinese medicine.  相似文献   

18.
The injury and cumulative effects of UV emission from fluorescence lamp were studied. UV intensity from fluorescence lamp was measured, and human skin samples (hips, 10 volunteers) were exposed to low‐dose UV irradiation (three times per week for 13 consecutive weeks). Three groups were examined: control group without UV radiation; low‐dose group with a cumulative dose of 50 J cm?2 which was equivalent to irradiation of the face during indoor work for 1.5 years; and high‐dose group with 1000 J cm?2 cumulative dose equivalent to irradiation of the face during outdoor activities for 1 year. Specific indicators were measured before and after UVA irradiation. The findings showed that extending the low‐dose UVA exposure decreased the skin moisture content and increased the transepidermal water loss as well as induced skin color changes (decreased L* value, increased M index). Furthermore, irradiated skin showed an increased thickness of cuticle and epidermis, skin edema, light color and unclear staining collagen fibers in the dermis, and elastic fiber fragmentation. In addition, MMP‐1, p53 and SIRT1 expression was also increased. Long‐term exposure of low‐dose UVA radiation enhanced skin photoaging. The safety of the fluorescent lamp needs our attention.  相似文献   

19.
Three aluminum compounds, namely alumina, aluminum hydroxide, and boehmite, are probed as the metal sources for the hydrothermal synthesis of a typical metal–organic framework MIL‐53(Al). The process exhibits enhanced synthetic efficiency without the generation of strongly acidic byproducts. The time‐course monitoring of conversion from different aluminum sources into MIL‐53(Al) is achieved by multiple characterization that reveals a similar but differentiated crystallinity, porosity, and morphology relative to typical MIL‐53(Al) prepared from water‐soluble aluminum salts. Moreover, the prepared MIL‐53(Al) constructed with the three insoluble aluminum sources exhibit an improved thermal stability of up to nearly 600 °C and enhanced yields. Alumina and boehmite are more preferable than aluminum hydroxide in terms of product porosity, yield, and reaction time. The adsorption performances of a typical environmental endocrine disruptor, dimethyl phthalate, on the prepared MIL‐53(Al) samples are also investigated. The improved structural stability of MIL‐53(Al) prepared from these alternative aluminum sources enables double‐enhanced adsorption performance (up to 206 mg g?1) relative to the conventionally obtained MIL‐53(Al).  相似文献   

20.
Osteoarthritis (OA) is a degenerative joint disease that affects the entire joint and has been a tremendous burden on the health care system worldwide. Although cell therapy has made significant progress in the treatment of OA and cartilage regeneration, there are still a series of problems. Recently, more and more evidence shows that extracellular vesicles (EVs) play an important role in the progression and treatment of OA. Here, we discuss that EVs from different cell sources not only participate in OA progression, but can also be used as effective tools for the diagnosis and treatment of OA. In addition, cell pretreatment strategies and EV tissue engineering play an increasingly prominent role in the field of OA treatment. This article will systematically review the latest developments in these areas. As stated above, it may provide new insights for improving OA and cartilage regeneration.  相似文献   

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