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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.
A number of essential trace elements play a major role in various metabolic pathways and in many diseases like autoimmune, neurological and psychiatric. This study is undertaken with an aim to evaluate the levels of different trace elements in the scalp hair samples of patients suffering from alcohol induced psychosis by particle induced X-ray emission technique (PIXE). It is observed that Fe (p?<?0.0005), Cu (p?<?0.001) are significantly higher in the hair samples of alcohol induced psychosis patients compared to those in normals while concentrations of Mn (p?<?0.005) and Zn (p?<?0.0001) are lower. The concentrations of Co and Ni in the hair samples are found to be in consonance with the concentrations in the normals.  相似文献   

3.
Acetogen strain Clostridium sp. MT1121 produced 300?mM acetate (p?<?0.005) and 321?mM ethanol (p?<?0.005) from synthesis gas (syngas) blend 60?% CO and 40?%?H2. Clostridium sp. MT1121 was metabolically engineered to eliminate production of either acetate or acetaldehyde during syngas fermentation. We used Cre-lox66/lox71-based gene removal system to eliminate either phosphotransacetylase (pta), or acetaldehyde dehydrogenase (aldh). The resulted biocatalyst with eliminated pta increased ethanol yield to 610?mM (p?<?0.005). Inactivation of pta rendered only 502?mM of ethanol (p?<?0.005). The acetogen biocatalyst with eliminated aldh produced 450?mM acetate (p?<?0.005). The role of cell energy pool preservation for re-directed carbon flux is discussed. This is the first report on time- and cost-efficient gene elimination in acetogens using lox66/lox71 gene elimination system.  相似文献   

4.
3,4-Methylenedioxymethamphetamine (MDMA) is an illicit phenethylamine ingested for entactogenic and euphoric effects. Although blood is more commonly submitted for forensic analysis, previous human MDMA pharmacokinetics research focused on plasma data; no direct blood–plasma comparisons were drawn. Blood and plasma specimens from 50 healthy adult volunteers (33 males, 17 females, 36 African-American) who ingested recreational 1.0 and 1.6 mg/kg MDMA doses were quantified for MDMA and metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA), 3,4-methylenedioxyamphetamine (MDA), and 4-hydroxy-3-methoxyamphetamine (HMA) by two-dimensional gas chromatography–mass spectrometry. Specimens were collected up to 3 h post-dose and evaluated for maximum concentration (C max), first detection time (t first), time of C max (t max), and 3-h area under the curve (AUC0–3 h); as well as blood metabolite ratios and blood/plasma ratios. Median blood MDMA and MDA C max were significantly greater (p?<?0.0005) than in plasma, but HMMA was significantly less (p?<?0.0005). HMA was detected in few blood specimens, at low concentrations. Nonlinear pharmacokinetics were not observed for MDMA or MDA in this absorptive phase, but HMMA C max and AUC0–3 h were similar for both doses despite the 1.6-fold dose difference. Blood MDA/MDMA and MDA/HMMA significantly increased (p?<?0.0001) over the 3-h time course, and HMMA/MDMA significantly decreased (p?<?0.0001). Blood MDMA C max was significantly greater in females (p?=?0.010) after the low dose only. Low-dose HMMA AUC0–3 h was significantly decreased in females’ blood and plasma (p?=?0.027) and in African-Americans’ plasma (p?=?0.035). These data provide valuable insight into MDMA blood–plasma relationships for forensic interpretation and evidence of sex- and race-based differential metabolism and risk profiles.
Figure
Median (interquartile range) blood/plasma 3,4-methylenedioxymethamphetamine (MDMA) (a), 4-hydroxy-3-methoxymethamphetamine (HMMA) (b), and 3,4-methylenedioxyamphetamine (MDA) (c) ratios for 3 h after controlled MDMA administration. Changes over time were significant after the 1.6 mg/kg dose for HMMA and MDA (p?=?0.013 and p?=?0.021), but not for MDMA. No changes over time were significant after the 1.0 mg/kg dose. Note: y-axes do not begin at 0. *p ?<?0.05 (low vs. high)  相似文献   

5.
Oral fluid (OF) offers a noninvasive sample collection for drug testing. However, 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) in OF has not been adequately characterized in comparison to plasma. We administered oral low-dose (1.0 mg/kg) and high-dose (1.6 mg/kg) MDMA to 26 participants and collected simultaneous OF and plasma specimens for up to 143 h after dosing. We compared OF/plasma (OF/P) ratios, time of initial detection (t first), maximal concentrations (C max), time of peak concentrations (t max), time of last detection (t last), clearance, and 3,4-methylenedioxyamphetamine (MDA)-to-MDMA ratios over time. For OF MDMA and MDA, C max was higher, t last was later, and clearance was slower compared to plasma. For OF MDA only, t first was later compared to plasma. Median (range) OF/P ratios were 5.6 (0.1–52.3) for MDMA and 3.7 (0.7–24.3) for MDA. OF and plasma concentrations were weakly but significantly correlated (MDMA: R 2?=?0.438, MDA: R 2?=?0.197, p?<?0.0001). Median OF/P ratios were significantly higher following high dose administration: MDMA low?=?5.2 (0.1–40.4), high?=?6.0 (0.4–52.3, p?<?0.05); MDA low?=?3.3 (0.7–17.1), high?=?4.1 (0.9–24.3, p?<?0.001). There was a large inter-subject variation in OF/P ratios. The MDA/MDMA ratios in plasma were higher than those in OF (p?<?0.001), and the MDA/MDMA ratios significantly increased over time in OF and plasma. The MDMA and MDA concentrations were higher in OF than in plasma. OF and plasma concentrations were correlated, but large inter-subject variability precludes the estimation of plasma concentrations from OF.
Figure
Oral fluid and plasma 3,4-methylenedioxymethamphetamine (MDMA) concentrations in all simultaneously collected paired-positive specimens collected ?0.25 to 143 h after 1.0 and 1.6 mg/kg oral MDMA administration to 26 adult participants  相似文献   

6.
Nonalcoholic steatohepatitis (NASH) can progress into liver cirrhosis; however, no definite treatment is available. Omega-3 polyunsaturated fatty acid (omega-3) has been reported to alleviate experimental NASH, although its beneficial effect was not evident when tested clinically. Thus, this study aimed to investigate the additive effect of omega-3 and ursodeoxycholic acid (UDCA) on diet-induced NASH in mice. C57BL/6 mice were given a high-fat diet (HFD) for 24 weeks, at which point the mice were divided into three groups and fed HFD alone, HFD with omega-3 or HFD with omega-3 in combination with UDCA for another 24 weeks. Feeding mice an HFD and administering omega-3 improved histologically assessed liver fibrosis, and UDCA in combination with omega-3 further attenuated this disease. The assessment of collagen α1(I) expression agreed with the histological evaluation. Omega-3 in combination with UDCA resulted in a significant attenuation of inflammation whereas administering omega-3 alone failed to improve histologically assessed liver inflammation. Quantitative analysis of tumor necrosis factor α showed an additive effect of omega-3 and UDCA on liver inflammation. HFD-induced hepatic triglyceride accumulation was attenuated by omega-3 and adding UDCA accentuated this effect. In accordance with this result, the expression of sterol regulatory binding protein-1c decreased after omega-3 administration and adding UDCA further diminished SREBP-1c expression. The expression of inducible nitric oxide synthase (iNOS), which may reflect oxidative stress-induced tissue damage, was suppressed by omega-3 administration and adding UDCA further attenuated iNOS expression. These results demonstrated an additive effect of omega-3 and UDCA for alleviating fibrosis, inflammation and steatosis in diet-induced NASH.  相似文献   

7.
The effect of gamma irradiation (0.5, 1, 2, and 4 kGy) on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. At Day 0 of irradiation, the pH, redness (CIE a?), yellowness (CIE b?), 2-thiobarbituric acid-reactive substances (TBARS) and volatile basic nitrogen (VBN) values of samples irradiated at 2 and 4 kGy were higher (p<0.05), but the CIE L? values (lightness) were lower than those of the non-irradiated control (p<0.05). At<1 kGy irradiation, however, the pH, CIE L?, CIE a? and CIE b?-value of samples were not significantly influenced by irradiation. The CIE a?, and CIE b?-values of samples irradiated at 2 and 4 kGy decreased with the increase of storage time. The VBN, TBARS, and CIE L?-values of samples irradiated at 4 kGy were not changed significantly during refrigerated storage for 90 days (p>0.05). The total plate counts (TPC) and lactic acid bacteria (LAB) in the samples irradiated at 4 kGy were significantly lower (p<0.01) than those with lower irradiation doses. At the end of storage, the TPC, coliform, and LAB in the samples were not increased after irradiation at 1, 0.5 and 1 kGy, respectively. TPC and LAB were not detected in samples irradiated at 4 kGy at Day 90. In addition, no coliform bacteria were found in samples irradiated at 1 kGy during refrigerated storage. Sensory evaluation indicated that the rancid flavor of samples irradiated at 4 kGy was significantly higher, but aroma and taste scores were lower than those of the control at Day 3 of storage. Irradiation of dry fermented sausages at 2 kGy was the best conditions to prolong the shelf-life and decrease the rancid flavor without significant quality deterioration.  相似文献   

8.
Nanoparticles, microsphere, hedgehog sphere-like and flower-like ZnO:Fe photocatalysts were prepared by the hydrothermal method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet/visible absorption spectra (UV?CVis). The results show that the ZnO:Fe photocatalysts with different 3D morphologies are a hexagonal wurtzite structure with space group of p63mc. The pH value of the precursor has a great influence on various morphologies of ZnO:Fe photocatalysts. The flower-like and hedgehog sphere-like ZnO:Fe photocatalysts exhibit the high solar photocatalytic behavior on methylene blue (MB). The ZnO:Fe order of photocatalytic activity is as follows: flower?>?hedgehog sphere?>?microsphere?>?nanoparticle. The flower-like ZnO:Fe is optimal, which exhibits the highest degradation rate of 98% for light time of 5?h.  相似文献   

9.
Recent work has suggested a microbial dysbiosis association between the lung and gut in respiratory diseases. Here, we demonstrated that gut microbiome modulation attenuated emphysema development. To modulate the gut microbiome, fecal microbiota transplantation (FMT) and diet modification were adopted in mice exposed to smoking and poly I:C for the emphysema model. We analyzed the severity of emphysema by the mean linear intercept (MLI) and apoptosis by the fluorescent TUNEL assay. Microbiome analysis was also performed in feces and fecal extracellular vesicles (EVs). The MLI was significantly increased with smoking exposure. FMT or a high-fiber diet (HFD) attenuated the increase. Weight loss, combined with smoking exposure, was not noted in mice with FMT. HFD significantly decreased macrophages and lymphocytes in bronchoalveolar lavage fluid. Furthermore, IL-6 and IFN-γ were decreased in the bronchoalveolar lavage fluid and serum. The TUNEL score was significantly lower in mice with FMT or HFD, suggesting decreased cell apoptosis. In the microbiome analysis, Bacteroidaceae and Lachnospiraceae, which are alleged to metabolize fiber into short-chain fatty acids (SCFAs), increased at the family level with FMT and HFD. FMT and HFD attenuated emphysema development via local and systemic inhibition of inflammation and changes in gut microbiota composition, which could provide a new paradigm in COPD treatment.Subject terms: Respiratory tract diseases, Translational research  相似文献   

10.
Using a combination of conventional sequential techniques, the batch growth conditions for the production of cell-envelope-associated proteinases have for the first time been studied and optimised in Lactobacillus delbrueckii subsp. lactis 313 (ATCC 7830; LDL 313). Concentrations of inoculum (0.1?<?X?<?10?% vol/vol), agitation speed (0?<?S?<?200?rpm), varying incubation temperature (30?<?T?<?50?°C), starting pH (4.5?<?pH?<?7) and carbon/nitrogen ratio of production medium (0.2?<?r?<?5) had an individual effect on proteinase yield (p?<?0.01). Optimal conditions for proteinase production included an initial pH of 6.0, 45?°C incubation temperature, 2?% (v/v) inoculum size of OD560?=?1, 150?rpm agitation speed, and growth medium carbon/nitrogen ratio of 1.0. Maximum proteinase activity obtained for whole cells was 0.99 U/ml after 8?h of incubation. The variables studied are very relevant due to their significance in improving the productivity of proteinase synthesis from LDL 313, under process and, likely, economic optimum conditions.  相似文献   

11.
12.
LC Tissue Distribution Study of Paeonol in Rats after Oral Administration   总被引:1,自引:0,他引:1  
Paeonol, an important constituent of the traditional Chinese medicine Cortex Moutan, has a variety of bioactivity. A simple and sensitive HPLC?CUV method has been developed for analysis of paeonol in different rat tissue (heart, liver, spleen, lung, kidney, and brain). Bio-samples were prepared by simple protein precipitation, and separation of paeonol was achieved on a C18 column with methanol?C2% glacial acetic acid solution 70:30 (v/v) as mobile phase at a flow rate of 1.0 mL min?1. UV detection was at 274 nm and the column temperature was 30 °C. Linearity was good between 0.025 and 5.0 ??g mL?1 (r 2 ?? 0.9990) for tissue samples. Inter-day and intra-day accuracy (as relative error, RE) and precision (as relative standard deviation, RSD) were <5.94 and 6.05%, respectively. The limit of detection was 0.025 ??g mL?1 and extraction recovery for all samples was ??85.86%. The method was successfully applied to a tissue-distribution study after oral administration of 40 mg kg?1 paeonol to healthy Sprague?CDawley rats. The study showed that paeonol was quickly distributed and eliminated after oral administration; liver and kidney were the major distribution tissues of paeonol in rats, and paeonol quickly passed through the blood?Cbrain barrier. It was also found there was no long-term accumulation of paeonol in rat tissues.  相似文献   

13.
Acetogen Clostridum sp. MT1962 produced 287 mM acetate (p?<?0.005) and 293 mM ethanol (p?<?0.005) fermenting synthesis gas blend 60 % CO and 40 %?H2 in single-stage continuous fermentation. This strain was metabolically engineered to the biocatalyst Clostridium sp. MTButOH1365. The engineered biocatalyst lost production of ethanol and acetate while initiated the production of 297 mM of n-butanol (p?<?0.005). The metabolic engineering comprised Cre-lox66/lox71-based elimination of phosphotransacetylase and acetaldehyde dehydrogenase along with integration to chromosome synthetic thiolase, 3-hydroxy butyryl-CoA dehydrogenase, crotonase, butyryl-CoA dehydrogenase, butyraldehyde dehydrogenase, and NAD-dependent butanol dehydrogenase. This is the first report on elimination of acetate and ethanol production genes and expression of synthetic gene cluster encoding n-butanol biosynthesis pathway in acetogen biocatalyst for selective fuel n-butanol production with no antibiotic support for the introduced genes.  相似文献   

14.
The methanol leaf extract of Mallotus oppositifolius was evaluated for anti-inflammatory activity in rats and mice using acute and chronic anti-inflammatory models with acetylsalicylate acid (aspirin) as the reference drug. The antioxidant activity was done in vitro using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-hydrazyl (DPPH) spectrophotometric assays. The extract dose dependently and significantly reduced paw edema volume in rats induced by carrageenan (p < 0.01), decreased croton oil-induced ear inflammation (p < 0.05), inhibited cotton pellet-induced granuloma in mice and reduced the rat paw thickness in formalin-induced arthritis.  相似文献   

15.
Inflammation of the gastrointestinal tract is associated with reactive oxygen species (ROS) genesis. Alleviation of oxidative stress is achieved by using antioxidants and probiotics. Present study investigates a synergistic effect of the probiotic Escherichia coli CFR 16 containing Vitreoscilla haemoglobin gene (vgb), green fluorescent protein (gfp) gene and pyrroloquinoline quinone (pqq) gene cluster on oxidative stress induced by 1,2-dimethylhydrazine (DMH). Adult virgin Charles foster male rats (3–4 months) weighing 200–250 g were administered with DMH (25 mg/kg body weight, s.c.) twice a week for eight consecutive weeks. Rats receiving only DMH dose showed increased lipid peroxidation in liver and intestinal tissues with reduced activity of antioxidant enzymes, i.e. superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Oral dose of E. coli CFR 16::vgb-gfp harbouring pqq gene cluster increased rat faecal PQQ concentration by twofold, reduced lipid peroxidation and retained SOD, CAT and GPx activities close to normal levels in liver and colonic tissues following DMH treatment. In addition, significant protection was found in colonic histological sections of these rat groups. This study demonstrates a protective efficacy in the following order: E. coli CFR 16?<?E. coli CFR 16::vgb-gfp?<?vitamin C?=?PQQ?<?E. coli CFR 16::vgb-gfp (pqq).  相似文献   

16.
Abstract

We examined the ability of Bothrops jararaca venom (12.5?mg/kg) injected intraperitoneally (i.p.) to cause acute kidney injury (AKI) in rats. Blood urea and creatinine (AKI biomarkers, in g dL?1) were elevated after 2?h in venom-treated rats (urea: from 0.41?±?0.1 to 0.7?±?0.03; creatinine from 46.7?±?3.1 to 85?±?6.7; p?<?0.05; n?=?3 each), with no change in circulating reduced glutathione. Venom-treated rats survived for ~6?h, at which point platelets were reduced (×103 µL?1; from 763.8?±?30.2 to 52.5?±?18.2) whereas leukocytes and erythrocytes were slightly increased (from 4.7?±?0.3 to 6.6?±?0.1?×?103?µL?1 and from 8.38?±?0.1 to 9.2?±?0.09?×?106?µL?1, respectively; p?<?0.05); blood protein (5.2?±?0.4?g dL?1) and albumin (2.7?±?0.1?g dL?1) were normal, whereas blood and urinary urea and creatinine were increased. All parameters returned to normal with antivenom given 2?h post-envenomation. The i.p. injection of venom caused AKI similar to that seen with other routes of administration.  相似文献   

17.
A disposable electrochemical test strip for determining clinically relevant concentrations of theophylline (0–300 μM) in whole blood is described, based on the generation of p-aminophenol from p-aminophenyl phosphate by the action of bovine liver alkaline phosphatase. Theophylline is an uncompetitive inhibitor of alkaline phosphatase and thus inhibits this process. The test strip consists of a screen-printed, carbon-based electrode system containing the enzyme and substrate in separate layers. Application of a 20-μl blood sample to the strip initiates the enzymic reaction, which will proceed to an extent that is inversely dependent on the amount of theophylline in the sample. After a 2-min incubation, the p-aminophenol generated is quantified by its electrochemical oxidation at + 150 mV (vs. Ag/AgCl) on the underlying carbon electrode. Caffeine and theobromine (0–1 mM), phenylalanine (< mM) and endogenous alkaline phosphatase (<2 U ml ?1) do not interfere.  相似文献   

18.
Vitamin D is well known for its role in maintaining calcium and phosphorus homeostasis and in promoting bone mineralization; however, more of its pleiotropic effects have been described recently. The aim of the present investigation was to study the effect of vitamin D treatment on skeletal muscles changes under different dietary conditions using an animal model. Four groups of C57BL/6J mice (n = 11 each) were maintained on either low fat diet (LFD) or high fat diet ??(HFD) with and without 1α,25-dihydroxyvitamin D3 (calcitriol) for 16 weeks. Animal weigh was recorded at baseline and then regular intervals, and at the end of the study, skeletal muscle tissues were harvested for the evaluation of the histopathological and ultrastructural changes. When control C57BL/6J mice were fed high-fat diet for 12 weeks, body weight gain was significantly increased compared with mice fed a LFD. (30.2% vs. 8.4%, p < 0.01). There was a significant gradual decrease in the weight of HFD fed mice that were treated with vitamin D as compared with a steady increase in the weights of controls (6.8% vs. 28.7%, p < 0.01). While the LFD group showed some ultrastructural changes, HDF fed on mice showed great muscle structural abnormalities. The whole sarcosome along with its membrane and cristae were severely damaged with scattered myocytes in HFD group. Furthermore, the mitochondria appeared weak and were on the verge of degenerations. The bands were diminished with loss of connections among myofibrils. These changes were attenuated in the HFD group treated with vitamin D with tissues have regained their normal structural appearance. The current findings indicate an important effect of vitamin D on skeletal muscle histology under HFD conditions.  相似文献   

19.
20.
The results of an investigation of heat transfer in a new type of insulation (microsphere insulation) are presented. The effects of the microsphere diameter, the concentration of metallized microspheres and the residual gas pressure on the thermal conductivity of the insulation were investigated. Measurements were made of the thermal conductivity at 77 to 300 K of microspheres with differing diameters (e.g. 95, 130 and 270 μm) and of samples with silver metallized microsphere concentrations of 7 and 32%. Measurements of average thermal conductivity (77–296 K) were made at residual gas pressuresk(p) in the range from 10?3 Pa to 105 Pa for pure nitrogen. The component of heat transfer by gas,k gc (p), was estimated.  相似文献   

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