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1.
The present experiment was designed to study the 2.45 GHz low-level microwave (MW) irradiation-induced stress response and its effect on implantation or pregnancy in female mice. Twelve-week-old mice were exposed to MW radiation (continuous wave for 2 h/day for 45 days, frequency 2.45 GHz, power density?=?0.033549 mW/cm2, and specific absorption rate?=?0.023023 W/kg). At the end of a total of 45 days of exposure, mice were sacrificed, implantation sites were monitored, blood was processed to study stress parameters (hemoglobin, RBC and WBC count, and neutrophil/lymphocyte (N/L) ratio), the brain was processed for comet assay, and plasma was used for nitric oxide (NO), progesterone and estradiol estimation. Reactive oxygen species (ROS) and the activities of ROS-scavenging enzymes— superoxide dismutase, catalase, and glutathione peroxidase—were determined in the liver, kidney and ovary. We observed that implantation sites were affected significantly in MW-irradiated mice as compared to control. Further, in addition to a significant increase in ROS, hemoglobin (p?<?0.001), RBC and WBC counts (p?<?0.001), N/L ratio (p?<?0.01), DNA damage (p?<?0.001) in brain cells, and plasma estradiol concentration (p?<?0.05), a significant decrease was observed in NO level (p?<?0.05) and antioxidant enzyme activities of MW-exposed mice. Our findings led us to conclude that a low level of MW irradiation-induced oxidative stress not only suppresses implantation, but it may also lead to deformity of the embryo in case pregnancy continues. We also suggest that MW radiation-induced oxidative stress by increasing ROS production in the body may lead to DNA strand breakage in the brain cells and implantation failure/resorption or abnormal pregnancy in mice.  相似文献   

2.
Andrographis nallamalayana is being widely used as tribal medicine in the treatment of leucoderma and mouth ulcers. Chemical profiling of methanolic extract of the whole plant (PE), using GC–MS and LC–MS, revealed the presence of compounds viz. α-tocopherol, β-sitosterol, tetradecanoic acid, monostearin, flavones/flavanones and their glycosides, chromones, etc. Topical application of imiquimod on the dorsal portion of male BALB/C mice resulted in the development of psoriatic symptoms (erythema, scaling, thickening and folding) with a mean disease activity index (DAI) of >7.0. Topical treatment with 100-μL PE (~6.4%/12.8%) formulations, for 12-days, resulted in the alleviation of disease symptoms. Compared to water-based formulations, emu oil-based formulation, PE400EO was found more effective in reducing the mean DAI (>84%), keratinocyte count (>65%) (p < 0.01) and interleukin-22 (~70%) (p < 0.05). We report, for the first time, anti-psoriatic activity of A. nallamalayana having great potential in developing a potent phytomedicine against psoriasis.  相似文献   

3.
Chemical separation methods in conjunction with instrumental neutron activation analysis (INAA) were developed for measuring iodine levels in commercially available bovine milk with varying milk fat (MF) content. Samples of homogenized (3.25 % MF), partly skimmed (2 % MF), partly skimmed (1 % MF), partly skimmed calcium enriched (1 % MF + Ca), and skim (<0.05 %) milk were purchased from local supermarkets. Ion exchange chromatography, solvent extraction, and ammonium sulfate precipitation methods were applied to the separation of the inorganic, lipidic and proteic fractions of iodine in milk. The levels of iodine were measured by INAA in total reactor and epi-cadmium (EINAA) neutron flux in conjunction with conventional gamma-ray and Compton suppression spectrometry (CSS). A pseudo-cyclic INAA method coupled with CSS (PC-INAA-CSS) was also explored as an instrumental option to further lower the detection limit of iodine. The detection limits of 0.06, 0.06 and 0.02 μg mL?1 for iodine were obtained using INAA-CSS, EINAA-CSS, and PC-INAA-CSS methods, respectively. Although the PC-INAA-CSS method provided the lowest detection limit, the INAA-CSS method was sufficient for the determination of total iodine in almost all samples analyzed in this work. The total iodine concentrations (μg mL?1) were: 0.40 ± 0.01 (in 3.25 % MF), 0.40 ± 0.01 (2 % MF), 0.42 ± 0.01 (1 % MF), 0.42 ± 0.01 (<0.05 %), and 0.96 ± 0.01 (1 % MF + Ca) milk samples. Iodine bound to various fractions of the milk samples analyzed, in percent of total iodine content, ranged: (0.05–1.8), (1.9–4.8), (90–95) for the lipidic, proteic and anionic inorganic fractions respectively. Iodine recovery in all cases was higher than 96 %.  相似文献   

4.
The study was conducted with the objective to assess soil enzymatic, microbial, and chemical properties by customary methods and results obtained by conventional methods, corroborated with microcalorimetry. The experiment was laid out in a randomized complete block design with ten treatments in triplicates. The RS and GM were used at three rates (0, 5, and 25 mg g?1 soil, respectively). The soils were maintained at two water levels 25 % (W1) and 200 % (W2) of soil water-holding capacity. All soil enzymatic, microbial, and chemical properties were measured by standard methods. The incorporation of GM and RS, especially at high rates and water levels, 25 % (W1) and 200 % (W2) significantly (p < 0.05) affected the soil enzymatic, microbial, and chemical properties compared to controls. The microcalorimetric parameters P max and k were positively correlated, whereas t max negatively linked with the results of enzymatic, microbial, and chemical properties at p < 0.01. Conversely, Q elucidated non-significant correlation (p < 0.05) to urease (0.248), neutral phosphatase (0.281), dehydrogenase (0.291), MBC (0.283), MBP (0.277), DOC (0.269), DON (0.190), SOM (0.284), and pH (0.047). Our results suggested that calorimetric parameters P max, t max, and k are highly sensitive and could be used as indices of soil enzymatic, microbial, and chemical properties, while Q is an indigent indicator.  相似文献   

5.
A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method for the analysis of triallate residue in wheat and soil was developed and validated. Multi-walled carbon nanotubes were used as clean-up sorbent. The residual levels and dissipation rates of triallate in wheat and soil were determined by liquid chromatography–tandem mass spectrometry. The limit of quantification was established as 0.01, 0.02 and 0.05 mg kg?1 for soil, wheat and wheat plant samples, respectively. The average recoveries of triallate ranged from 77% to 108% at fortified levels of 0.01–0.5 mg kg?1 with relative standard deviations of 3.0–8.4% (n = 5). From residue trials at three geographical experimental plots in China, the results showed that the half-lives of triallate in soils were 1.13–1.63 days. For trials applied according to the label recommendation, the final residues of triallate in wheat at harvest time were all below 0.05 mg kg?1 (the maximum residue levels of China, Japan, Korea and the US).  相似文献   

6.
Nassarius reticulatus (whelk) imposex levels and organotin body burden (b.b.) were surveyed along the Portuguese coast, from Vila Praia de Âncora (northern limit) to Lagos (southern limit), between May and August 2003. The percentage of females affected with imposex (%I), the relative penis length index (RPLI), the vas deferens sequence index (VDSI) and the degree of female oviduct convolution index (AOS) were used to assess the level of imposex at each site. These imposex indices were determined for 23 sampling stations throughout the coast and were in the range 0.0–100%, 0.0–90%, 0.0–5.0 and 0.0–1.3 respectively. Sterile females (i.e. females carrying aborted egg capsules inside the capsule gland) were found inside the harbours of Viana do Castelo (8.5%) and Aveiro (3.7%). Organotin compounds were assessed at 10 sampling sites spread along the coast. Tributyltin (TBT) b.b. in females varied between 39 and 1679 ng g?1 (as tin) dry weight, and dibutyltin (DBT) and monobutyltin (MBT) varied in the ranges 23–1084 ng g?1 (as tin) d and 18–939 ng g?1 dry wt respectively. Among the butyltins, the major fraction corresponded to TBT (47.4%), followed by DBT (27.6%) and MBT (25.0%), which indicates recent TBT inputs. Triphenyltin (TPT) levels ranged from <5 to 21 ng g?1 (as tin), and, when quantifiable, represented on average 10% of that of TBT. TPT was the dominant phenyltin and was detected in 60% of the sampling stations. The imposex was significantly correlated to ln (TBT) (Spearman r = 0.918, p < 0.001 for RPLI; r = 0.864, p < 0.001 for VDSI; r = 0.828, p < 0.01 for AOS). The higher levels of imposex and TBT contamination occurred inside or close to harbours, which we identified as ‘hotspots’ of pollution along the coast. Comparing the results obtained in the current work with those reported in a similar survey in 2000, imposex and TBT b.b. varied locally but did not reveal any global trend in the variation of TBT pollution along the Portuguese coast over the 3 year period. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

7.
Study evaluates testis mass in rats subjected to early weaning and subsequently nourished with diet containing flour or flaxseed oil. Pups were weaned for separation from mothers at 14 days (early weaning, EW) and 21 days (control, C). After 21 days, the control group (C60) was nourished with control diet. EW was divided as: control (EWC60), flaxseed flour (EWFF60) and flaxseed oil (EWFO60) group diets for the next 60 days. At 21st and 60th day, body mass, serum cholesterol and triglycerides and testis mass were evaluated. At 21 day, EW group showed lower (p < 0.05) body mass, serum cholesterol and testis mass. At 60 days, EWC60 and EWFO60 groups showed lower (p < 0.05) body mass (vs. C60 and EWFF60). EWFF60 group showed lower (p < 0.05) serum cholesterol (vs. EWC60 and EWFO60) and higher (p < 0.05) testis mass (vs. C60, EWC60 and EWFO60). Flaxseed flour (vs. oil) was associated with higher testis mass following early weaning.  相似文献   

8.
The aim of this study is to determine the cutaneous wound healing effects of the ethanol extract of Cotinus coggygria leaves in rats by excision wound model to provide scientific evidence for the traditional use of C. coggygria Scop. The levels of malondialdehyde, catalase, superoxide dismutase, glutathione and hydroxyproline were investigated in wound tissues. Histopathological examination was also performed. The hydroxyproline content of the granulation tissue and the glutathione levels were both significantly higher in the treatment group than in the control group (p < 0.05 for both); while the malondialdehyde levels were significantly lower in the treatment group (p < 0.05). These results were supported with histological results. The ethanol extract of C. coggygria Scop could be considered as an effective agent in wound healing in accordance with its traditional use.  相似文献   

9.
Solubilizing the potent anticancer pigments in nanoemulsion (NE) systems containing 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) is a novel and promising strategy to incorporate them into water-based drug formulations. The concentration effects of sunflower oil (SO, 5.61–17.39% w/w), surfactant mixture of Tween 80 (T80) and Span 20 (S20) (1:1 weight ratio, 3.95–14.05% w/w), and the inclusion complex of HP-β-CD with canthaxanthin (CTX) synthesized by Dietzia natronolimnaea HS-1 (2.61–14.39% w/w) were evaluated to formulate a stable NE using ultrasound-assisted emulsification. The NEs were evaluated regarding droplet size and polydispersity index (span), physical stability, turbidity, and loss of antioxidant activity (LAA). Response surface modeling showed that the NEs containing 12% T80/S20, 8.30% SO, and 12% CTX/HP-β-CD had the lowest droplet size (105.5 nm), span (0.394), droplet growth ratio (0.112), turbidity (0.139), and LAA (9.36%). The predicted values obtained were close to the experimental values, indicating the suitability of the constructed models. Transmission electron microscopy and confocal laser-scanning microscopy also demonstrated that the formed droplets of the NEs produced at optimal formulation were spherical in the range of 20–100 nm. A significant correlation was found between droplet size with stability (r = ?0.960, p < 0.01) and turbidity (r 2 = 0.876, p < 0.01) values.  相似文献   

10.
Microbial fuel cell experimentation using waste streams is an increasingly popular field of study. One obstacle to comparing studies has been the lack of consistent conventions for reporting results such that meta-analysis can be used for large groups of experiments. Here, 134 unique microbial fuel cell experiments using waste substrates were compiled for analysis. Findings include that coulombic efficiency correlates positively with volumetric power density (p < 0.001), negatively with working volume (p < 0.05), and positively with percentage removal of chemical oxygen demand (p < 0.005). Power density in mW/m2 correlates positively with chemical oxygen demand loading (p < 0.005), and positively with maximum open-circuit voltage (p < 0.05). Finally, single-chamber versus double-chamber reactor configurations differ significantly in maximum open-circuit voltage (p < 0.005). Multiple linear regression to predict either power density or maximum open-circuit voltage produced no significant models due to the amount of multicollinearity between predictor variables. Results indicate that statistically relevant conclusions can be drawn from large microbial fuel cell datasets. Recommendations for future consistency in reporting results following a MIAMFCE convention (Minimum Information About a Microbial Fuel Cell Experiment) are included.  相似文献   

11.
This study evaluated the hypoglycemic effect of the oil extracted from the Acrocomia aculeata pulp (OPAC) in normoglycemic rats and streptozotocin (STZ), fructose-induced diabetic rat models and its in vitro antioxidant and cytotoxic potential. OPAC (3, 30 or 300 mg/kg, v.o.) significantly decreased (p < 0.05) the high glucose levels induced by a high fructose-diet in rats. Persistent treatment with OPAC for 24 days also reduced the high plasmatic glucose induced by STZ. In normoglycemic animals, OPAC significantly decreased glucose levels. While A. aculeata oil exhibited good in vitro antioxidant activity, no sign of cytotoxicity was observed in LLC-PK1 cells (5–500 μg/mL). OPAC has antidiabetic and antioxidant activities without causing in vitro cytotoxicity.  相似文献   

12.

A novel, simple and reliable reversed-phase liquid chromatography (LC)–spectrophotometric UV stability-indicating method was developed and validated for the simultaneous assay of marbofloxacin, clotrimazole and dexamethasone acetate in the presence of their impurities and degradation products in a pharmaceutical formulation for veterinary use. A C18 (75 × 4.6 mm, 4 µm) column was used with an acetonitrile–ammonium acetate mixture as mobile phase delivered with gradient elution. A diode-array detection was used in the 200–400 nm range and the detection wavelength was set at 260 nm. Validation carried out on the pharmaceutical dosage form, according to Veterinary International Conference on Harmonization guidelines, demonstrated excellent specificity, linearity, precision, accuracy and robustness. Excellent specificity with respect to vehicle and degradation products obtained after forced degradation (i.e., oxidation, acid, alkaline and thermal degradation) was demonstrated. As for linearity, the LC–UV assay method is applicable in the 0.180–0.420 mg mL−1 concentration range for marbofloxacin (r 2 = 0.99), 0.060–0.140 mg mL−1 for dexamethasone acetate (r 2 = 0.97) and 0.600–1.400 mg mL−1 for clotrimazole (r 2 = 0.98). Very good repeatability (RSD < 0.8 %) and inter-day precision (RSD < 2.5 %) were observed for all analytes. Accuracy was in the 93–104 %, 98–111 % and 99–108 % confidence interval (95 %) for marbofloxacin, dexamethasone acetate and clotrimazole, respectively. The variations (±20 %) of mobile phase flow rate and pH, and oven column temperature did not exhibit an impact on the analyte content accuracy, demonstrating the robustness of the method. The LC–UV method here developed and validated may be used routinely for quality control.

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13.
This study aimed to explore the possible mechanism of Achyranthis Bidentatae Radix for the treatment of osteoporosis using tandem mass tag-based proteomics technique combined with mass spectrometry. Proteomics techniques combined with bioinformatics were used to analyze the biological functions of differentially expressed proteins. In addition, western blotting was performed to verify the expression of related proteins. A total of 3,752 proteins were identifiable by proteomic analysis. Furthermore, 93 differentially expressed proteins were identified, of which 61 were upregulated and 32 were downregulated. Differentially expressed proteins were primarily associated with oxidative phosphorylation (p = 4.8 × 10−4) pathways and involved in transmembrane transport (p = 3.5 × 10−3), exocytic process (p = 1.2 × 10−2), cellular developmental process (p = 1.3 × 10−2), adenosine triphosphate metabolic process (p = 1.0 × 10−2) and other biological processes. Western blotting analysis showed that MT-CYB and NDUFA9 were differentially expressed in the bone microenvironment of rats with osteoporosis. We speculated that they were potential biomarkers linked to osteoporosis. This study employed proteomics to explore the potential therapeutic targets of Achyranthis Bidentatae Radix to treat osteoporosis. This revealed that mitochondria are a new target for the treatment of glucocorticoid-induced osteoporosis.  相似文献   

14.
Chalcones are a group of compounds widely distributed in plant kingdom. The aim of this study was to assess the neurite outgrowth stimulatory activity of selected chalcones, namely helichrysetin, xanthohumol and flavokawin-C. Using adherent rat pheochromocytoma (PC12 Adh) cells, the chalcones were subjected to neurite outgrowth assay and the extracellular nerve growth factor (NGF) levels were determined. Xanthohumol (10 μg/mL) displayed the highest (p < 0.05) percentage of neurite-bearing PC12 Adh cells and the highest (p < 0.05) NGF level in the culture medium of xanthohumol-treated cells. While, helichrysetin induced a moderately high numbers of neurite-bearing cells, flavokawin-C did not stimulate neurite outgrowth. This work supports the potential use of xanthohumol as a potential neuroactive compound to stimulate neurite outgrowth.  相似文献   

15.
From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium C+(aq) + Cs+(nb) ?C+ (nb) + Cs+(aq) taking place in the two–phase water–nitrobenzene system (C+ = methylammonium, ethylammonium, propylammonium, ethanolammonium, diethanolammonium, triethanolammonium, protonated tyramine, protonated dopamine, protonated DL–noradrenaline; 1 = hexaethyl p-tert-butylcalix[6]arene hexaacetate; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the C+ complex species in nitrobenzene saturated with water were calculated; they were found to increase in the following cation order: protonated tyramine < protonated dopamine < triethanolammonium < diethanolammonium < protonated DL-noradrenaline < propylammonium < ethanolammonium < ethylammonium < methylammonium.  相似文献   

16.
Park  Yang Ki  Chung  Woo Young  Kim  Byungsub  Kye  Young-sik  Shin  Moon-sik  Kim  Dongwook 《Chromatographia》2013,76(11):679-685

Ion-pair single-drop microextraction (SDME) coupled to gas chromatography–mass spectroscopy (GC–MS) methods for the determination of four degradation products of chemical warfare agents were investigated in water. Acidic analytes were converted into their ion-pair complexes with cation surfactants in aqueous sample and then extracted into the organic single drop containing the derivatising agent. Upon injection, the analytes were derivatised in the GC injection hot port. Parameters, such as type of extraction solvent, ion-pairing (IP) reagent, reagent concentration, salt concentration, stirring speed and pH, were all optimized. This method is reproducible for spiked water sample for four different analytes (RSDs < 9.33 %, n = 5) and linear (r 2 > 0.9945). The limit of detection (LOD) is in the range of 0.08–0.01 ng mL−1 (S/N = 5) under GC–MS selected ion monitoring mode. The method was successfully applied to the proficiency test samples from the Organization for Prohibition of Chemical Weapons (OPCW).

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17.
An analytical method based on TD-GC/MS was developed and validated for the determination of volatile organic compounds (VOCs), including linear and cyclic volatile methylsiloxanes (VMSs), in biogas. Biogas was first sampled in Supel? Inert Film bags and subsequently dynamically sampled onto multisorbent bed tubes (Carbotrap, Carbopack X and Carboxen 569) using portable pump equipment. Two sample volumes, 100 and 250 ml, were evaluated. Desorption efficiency values for both volumes are in the range of 99–100% for almost all studied compounds while breakthrough values (%VOC on sample tube back section) are below 1% for most evaluated VOCs. However, acetaldehyde, carbon disulphide, ethanol and 1,3-butadiene have breakthrough values higher than 5%. Method detection limits were in the range of 0.01–0.8 ng per sample. The most abundant VOCs in biogas were terpenes with concentrations between 500 and 700 mg m?3. Other important families were ketones, aromatic hydrocarbons and alkanes, with concentrations in the range of 36–46 , 20–35 and 14–16 mg m?3, respectively. VMSs presented average concentrations of 4.9 ± 0.4 mg m?3. Additionally, the Supel? Inert Film bags were evaluated for stability for 4 days at room temperature. Although several VOC families’ concentrations in the bag increased or decreased significantly (t-test; p ≤ 0.01, = 5) 2 days after collection, recoveries were around 70–130% for most studied VOCs. The results shown demonstrate that the presented methodology is reliable and satisfactory for the evaluation of VOCs in biogas and presents an alternative to the currently existing biogas analytical techniques.  相似文献   

18.
Effect of aqueous methanol extract of different colour sweet bell peppers (Capsicum annuum L.) on parameters of diabesity and carbonyl stress was analysed in vitro. Yellow pepper displayed significantly (p < 0.001) higher intestinal α-glucosidase inhibitory activity than green and red pepper. Porcine pancreatic lipase inhibitory activity was significantly (p < 0.01) high in yellow and red pepper than in green pepper. Green and red pepper inhibited vesperlysine-type advanced glycation end products (AGEs) more potently than yellow pepper; however, pentosidine-type AGEs were similarly inhibited by all three peppers. Yellow and red pepper inhibited lipid peroxidation more potently (p < 0.01) than green pepper. Total polyphenol content and free radicals scavenging activities in yellow and red bell peppers were higher than in green pepper. Total flavonoid content was high in green pepper than that present in yellow and red peppers. Green pepper displayed presence of proanthocyanins; however, oligomeric anthocyanins were detected in yellow and red peppers.  相似文献   

19.
Proton-ligand association constants of 1-benzoyl(1,2,4-triazol-3-yl)thiourea (BTTU) and its complex formation constants with some bivalent metal ions Ni(II), Co(II), Mn(II), Zn(II), and Cu(II), have been determined potentiometrically in 50% EtOH–H2O and 0.1 M NaNO3. The complexes formed in solution have a stoichiometry of 1:1 and 1:2 [M:L], where M represents the metal ion and L the BTTU ligand. The corresponding thermodynamic parameters are derived and discussed. The complexes are stabilized by enthalpy changes and the results suggest that complexation is an enthalpy-driven process. The effects of metal ion, ionic radius, electronegativity, and nature of ligand on the formation constants are discussed. The formation constants of the complexes with 3d transition metals follow the order Mn2+ < Co2+ < Ni2+ < Cu2+ > Zn2+. The metal complexes were synthesized and characterized by elemental analyses, conductance, IR, 1H NMR, and magnetic measurements. The low magnetic moment of 0.11 BM for the Cu(II) complex is suggestive of dimerization through Cu–Cu interaction. The concentration distribution diagrams of the complexes were evaluated. The ligands and their metal complexes have been screened in vitro against some bacteria and fungi.  相似文献   

20.
Trace elemental imbalance in human beings is postulated to exert action, directly or indirectly, on the carcinogenic process. The objective of this study was to evaluate the levels of trace elements in blood serum samples of lung cancer patients and analyze their alteration with respect to healthy controls. Particle induced X-ray emission (PIXE), a well established method for elemental analysis, was used to identify and quantify trace elements in the blood serum samples of the studied groups. The PIXE measurements were carried out using 2.5 MeV collimated proton beam from the 3 MV Tandem Pelletron Accelerator at Ion Beam Laboratory, Institute of Physics, Bhubaneswar, India. The serum of the cancerous group displayed increased concentrations of Ti, Ni, and Cu but lowered concentrations of V, Cr, Mn, Fe, Co, Zn, and Se. Statistically significant differences were found for serum Cr (p < 0.01), Fe (p < 0.0005), Ni (p < 0.05), Cu (p < 0.00005), and Zn (p < 0.0005) between the two studied groups. The copper to zinc ratio for the lung cancer group was 2.24 ± 0.39, which was almost three times the value for normal subjects (0.77 ± 0.14). The observed alterations are discussed with respect to the possible mechanisms by which these elements might influence the carcinogenic process. Significant reduction in mortality from lung cancer can be achieved by advances in early diagnosis and implementation of multidisciplinary treatment programmes leading to improvement of survivorship and better quality of life. It is expected that similar studies from all corners of the world would ultimately lead to the development of novel therapeutic agents to treat lung cancer.  相似文献   

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