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1.
The analgetic activity of Carica papaya leaves (CPL) extracts (n-hexane, ethyl acetate, ethanol) was investigated in mice model using acetic acid induced pain (Siegmund method). Experimental animals were divided into 11 groups and received n-hexane, ethyl acetate, and ethanol extracts at doses of 0.175, 0.35, 0.70 mg/kg bw orally; CMC-Na 0.5% (control group); 50 mg/ kg bw of aspirin. The results showed that all extracts at the doses of 0.175, 0.35 and 0.70 mg/kg bw gave significant analgetic activity (p<0.05) compared to control group. Ethanol extract of CPL dose of 0.70 mg/kg bw showed the best analgetic activity that was comparable to aspirin.  相似文献   

2.
The effects of ethanolic extracts of Mulberry Leaves (Morus alba L.) on nitric oxide (NO) serum level in rat and diameter of blood vessels in rabbit ear were investigated. NO level of ethanolic extract of mulberry leaves at dose of 100 mg/kg bw rats gave significant difference compared to negative control (P<0,05) at minute 30 after extract administration (4,51 ± 4,31 μM). Ethanolic extract of mulberry leaves at dose of 200 mg/kg bw had no significant difference in NO serum level. However, ethanolic extract of mulberry leaves at dose of 400 mg/kg bw rats increased NO serum level significantly compared to negative control (P<0,05) at minute 0, 10, 30, 60, and 90 after extract administration. The maximum serum level of NO of 400 mg/kg bw mulberry extract was 4,62 ± 3,05 μM, and it is the highest among other groups. Therefore this dose was choosen for vasodilatation assay in rabbit. Observation on blood vessels diameter in rabbit ears showed that ethanolic extract of mulberry leaves were able to dilatate the big vessels and small vessels of rabbit ears significantly compared to negative control (P<0,05) at minute 60 after extract administration. In conclusion, ethanolic extract of mulberry leaves at dose of 400 mg/kg bw rats or 202.67 mg/kg bw rabbits has a vasodilator effect, probably due to an increase of NO serum level.  相似文献   

3.
Systemic lupus erythematosus is a systemic autoimmune disease characterized by multisystem inflammation due to immune complex deposits in the organs like kidneys, joints, pleura, skin, and so on. Physalisangulata known as mullaca, has been widely studied for its pharmacological activities such as antiinflammatory, immunosuppressive, cytotoxic, and also inhibition of organ rejection in transplantation. This study was directed to investigate the activities of P. angulata extract as an immunomodulatory agent. P. angulata powder was extracted by maceration with 70% of ethanol. An animal model of lupus was obtained by an injection 0.7 mL of pristane, i.p. Successful induction obtained in two weeks after injection which can be monitored by measuring total leukocyte count. For ensuring successful induction, another test was done four weeks and eight weeks after injection by detecting the presence of specific antinuclear antibodies using SDS PAGE method. Other measured parameters were including nonspecific immune response (measurement of total leukocyte count and differential leukocyte count), specific humoral immune response (hemagglutination test), specific cellular immune responses (delayed type hypersensitivity test), organ index and histology of kidney and spleen. As the results shown, ethanolic extract of Physalisangulata at dose of 1000 mg/kg BW orally, gave immunomodulatory effect in Lupus rat model. The extract worked primarily on specific immune response by lowering immune response near to the normal value, it was not suppressing immune response as prednisone.  相似文献   

4.
Effect of steeped black tea (Camellia sinensis (L.) var. assamica) on immunoglobulin titer (IgM and IgG) and lymphocyte proliferation in responses to hepatitis B vaccine inBALB/c mice has been investigated. The study was divided into two stages i.e. the determination of immunoglobulin titer and the test of lymphocytes proliferation. In the first stage mice were divided into 5 groups each consisting of 5 mice. Group I, II and III was given steeped black tea respectively with a dose of 600 mg/kg bw; 1.2 g/kg bw and 2.4 g/kg bw. Group IV was given Stimuno® with a dose of 6.5 mg/kg bw, and group V was given aquadest as negative control. All groups were induced by hepatitis B vaccine on day-0 (after 7 days of acclimatization). Serum was taken on day-14 and 21 for measurement of IgM titer and IgG, respectively. In the second stage, the mice were grouped as in the first stage, then all groups were induced by hepatitis B vaccine at day-0 and day-7. On day-27 lymphocyte was isolated and then tested for the growth and proliferation of lymphocytes. The results of this study showed that the steeped black tea has an effect in increasingIgM and IgG titer of BALB/cmice induced by hepatitis B vaccine, where the most effective dose was 1.2 g/kg bw. Steeped black tea also could increase lymphocytes proliferation in mice BALB/cinduced by hepatitis B vaccine, where the most effective dose was 1.2 g/kg bw.  相似文献   

5.
Anti-inflammatory and antibacterial activities of some novel quinazolinones were determined. Evaluation of anti-inflammatory activity of test compounds was performed using carrageenan induced paw edema in rats. Oral administration of test compounds 25 mg/kg and 50 mg/kg reduced the paw edema significantly (P < 0.05) in a dose dependent manner compared to carrageenan induced rats. The test compounds were also screened for their antibacterial activity against the strains of Staphylococcus aureus and Escherichia coli at the concentrations of 200 μg/ml and 1 mg/ml. The test compounds showed better activity as that of the standard lincomycin at the tested higher concentration against S. aureus. None of the compounds exhibit comparable activity to that of the standard ceftazidime against E. coli.  相似文献   

6.
In this work, polyvinyl alcohol (PVA) protected silver grass-like nanostructure (PVA–Ag–GNS) with near infrared surface-enhanced Raman scattering (NIR-SERS) activity was prepared and employed to detect DNA and DNA bases. The PVA–Ag–GNS demonstrated high NIR-SERS activity and good optical reproducibility in the detection of adsorbates such as the case of crystal violet, DNA and DNA bases. By using of the tested molecule of thymine, the PVA–Ag–GNS shows a high enhancement factor (EF) of ∼108. For NIR-SERS detection of DNA molecules, Raman signals from the DNA bases of guanine (630 cm−1) and adenine (720 cm−1) are greatly enhanced. For DNA molecules NIR-SERS detection, Raman signals from the DNA bases of guanine (630 cm−1), adenine (720 cm−1) and cytosine (1010 cm−1) are greatly enhanced. The experimental results show that the NIR-SERS spectrum of DNA is dominated by guanine mode, which is followed by adenine and cytosine modes, respectively. Meanwhile, the NIR-SERS signal intensities of the DNA bases increase in the order of thymine (T) < cytosine (C) < adenine (A) < guanine (G). One can conclude that the adsorption strength of the DNA bases in DNA molecule with the silver surface is in the order T < C < A < G, which is different from that of the four DNA bases in individual molecule adsorbed on silver surface (T < A < G < C). On the other hand, the geometry optimization and calculated wavenumber of the complexes of adenine–Ag, guanine–Ag, cytosine–Ag and thymine–Ag for the ground states are performed with DFT, B3LYP functional and the LanL2DZ basis set. The calculated wavenumbers match well with the experimental results. According to our experiment and calculations, DNA base molecules adsorbed on silver surface via the intra-annular nitrogen atom which is adsorbed on the silver nanoparticle and formed metal–molecule complexes by the available lone pair.  相似文献   

7.
Diabetic wounds (DWs) are characterized by prolonged inflammation, which poses a significant challenge for clinicians and researchers to promote healing. In this study, we fabricate L-Glutamic acid (LGA) loaded collagen/chitosan (COL-CS) composite scaffold for the accelerated healing of DW. The characterization outcomes of the composite scaffold revealed that a crosslinked scaffold holds optimum porosity, low matrix degradation, and sustained drug release in contrast to a non-crosslinked scaffold. In vitro, LGA composite scaffolds have not exhibited any toxicity on 3T3L1 cell lines. In vivo, the LGA composite scaffold has shown significantly (p < 0.001), higher rates of wound contraction than those in control and COL-CS scaffold treated groups. In addition, MMP-9 levels were also significantly reduced in LGA composite scaffold-treated group compared with those in the control and COL-CS scaffold treated group. Thus, the LGA composite scaffold may serve as a promising therapy in DW due to its unique modulatory effect on inflammatory biomarker MMP-9.  相似文献   

8.
Lotus seeds are nutraceutically valued natural plant produce, which succumbs to microbial contamination, predominantly to toxigenic moulds. Results of the present study revealed seed coat portion to harbor higher proportion of microbial load, particularly fungi than cotyledon portion. Among the mycotoxins analyzed, aflatoxins (B1, B2, G1 and G2) were below detectable limits, while the seeds were devoid of Ochratoxin-A (OTA). Application of different doses of electron beam and gamma irradiation (0, 2.5, 5, 7.5, 10, 15 and 30 kGy) for decontamination purpose revealed significant dose-dependent decrease in the fungal contaminants (P<0.05). However, the contaminant yeasts could survive up to 10 kGy dose, which could be completely eliminated at 15 kGy. From the results obtained, a dose range between 10 and 15 kGy is recommended for complete decontamination, as these doses have also been shown earlier to have minimal effects on nutritional and functional properties of lotus seeds.  相似文献   

9.
Manganese(II) complex of (E)-2-(hydroxyl-5-methoxybenzylideneamino) phenol was synthesized and used as a suitable Mn(II) – selective membrane in PVC matrix. The plasticized membrane sensor exhibits a nersian response for Mn(II) ions over a wide concentration range of 6 × 10?6–2 × 10?2 M with slope of 29 ± 1 mV per decade. It has a response time of <11 s and can be used for 2 months without any measurable divergence in potential. The response of the proposed sensor is independent of pH between 4 and 9.5. The proposed sensor shows a fairly good discriminating ability towards Mn(II) in comparison with some hard and soft metals. The electrode was used in the determination of Mn(II) in aqueous solutions and as an indicator electrode in potentiometer titration of manganese ions against EDTA.  相似文献   

10.
We have evaluated the accuracy of the heat capacity option of a Quantum Design physical property measurement system (PPMS) by measuring the heat capacity of various types of conducting and insulating samples over the temperature range from (2 to 300) K. In particular, the accuracy of measurements on a copper pellet was determined to be ±2% for 2 K < T < 20 K and ±0.6% for 20 K < T < 300 K, however similar measurements on a powdered sample of benzoic acid had errors as high as 20%. A new method for heat capacity measurements of powdered samples using a PPMS system has been developed that allows us to obtain heat capacity measurements for both insulating and conducting powdered samples with an accuracy of ±1% from (20 to 300) K and ±2% to ±5% for T < 20 K. Since the heat capacity of substances (and corresponding entropy contribution) is small at low temperatures for lattice-only contributions, the accuracy of ±2% to ±5% below 20 K is considered acceptable. As a test of the new method, the heat capacity of powdered bulk hematite has been measured in the temperature range from (2 to 300) K with the PPMS, and its standard entropy at T = 298.15 K was calculated to be (87.33 and 87.27) J · K?1 · mol?1, which deviates ?0.08% and ?0.15% from the accepted reference value, respectively. We recommend that this new method become the standard for accurate heat capacity measurements on insulating powdered samples using a PPMS system and the corresponding thermodynamic calculations.  相似文献   

11.
A new PVC membrane based strontium(II) ion-selective electrode has been constructed using acetophenone semicarbazone as a neutral carrier. The sensor exhibits a Nerstian response for strontium(II) ion over a wide concentration range 1.0 × 10−2–1.0 × 10−7 M with the slope of 29.4 mV/per decade. The limit of detection was 2.7 × 10−8 M. It was relatively fast response time (<10 s for concentration ⩾1.0 × 10−3 and <15 s for concentration of ⩾1.0 × 10−6 M) and can be used for 8 months without any considerable divergence in potentials. The proposed sensor revealed relatively good selectivity and high sensitivity for strontium(II) over a mono, di, trivalent cation and can be used in a pH range of 2.5–10.5. It was also successfully used as an indicator electrode in potentiometer titration and in the analysis of concentration in various real samples.  相似文献   

12.
Enthalpies of solution of methanol and 2-methyl-2-propanol (tert-butanol) in pyridine and its methyl derivatives were investigated in the range of mole fractions of alcohol x⩽0.02 at temperature 298.15 K by a titration calorimeter. Dissolution of methanol is an exothermic process, with heat effects very close to those for water reported in part I of this study. The negative enthalpy of solution increases in the following order: pyridine < 3-methylpyridine < 4-methylpyridine < 2-methylpyridine < 2,6-dimethylpyridine < 2,4,6-trimethylpyridine. Positive enthalpies of solution of 2-methyl-2-propanol increase as follows: 2-methylpyridine < 2,4,6-trimethylpyridine < 4-methylpyridine < 2,6-dimethylpyridine < 3-methylpyridine < pyridine. The propensity of pyridine derivatives to hydrogen bonding is enhanced by the ortho effect. Methyl groups are probably too small to prevent the nitrogen atom in the pyridine ring from hydrogen bonding. However, spacious hydrocarbon group in 2-methyl-2-propanol molecule makes the bonding difficult for 2,6-dimethylpyridine and 2,4,6-trimethylpyridine, thus the number of O–H⋯N bonds is smaller than that in the solutions of methanol or water. The two latter seem to be very close to each other.  相似文献   

13.
Isobaric (vapor + liquid) equilibria of three binary systems (1-methoxy-2-propanol + 2-methoxyethanol), (2-butanone + 2-methoxyethanol) and (water + 2-methoxyethanol), was measured using an apparatus with dynamic recirculation and gas chromatography analysis for both phases. The measurements were carried out at pressures of (74.5, 101.3, and 134.0) kPa and temperature ranged from (343 to 407) K. No partial liquid miscibility was observed for any of the systems studied. Azeotropic behavior was verified for the system (water + 2-methoxyethanol) at the water-rich region. Thermodynamic modeling of the data measured was successfully accomplished for (2-butanone + 2-methoxyethanol) and (water + 2-methoxyethanol). In order to represent the no-ideality of the liquid phase, three alternatives for the activity coefficient model were used, Non Random Two Liquid, van Laar and Wilson. Results showed that the relative root mean square deviations from the experimental molar fractions were, <12% for the vapor phase, and <1% for the liquid phase.  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.
Isobaric (vapour + liquid) equilibrium measurements have been reported for the binary mixture of (1-pentanol + propionic acid) at (53.3 and 91.3) kPa. Liquid phase activity coefficients were calculated from the equilibrium data. The thermodynamic consistency of the experimental results was checked using the area test and direct test methods. According to these criteria, the measured (vapour + liquid) equilibrium results were found to be consistent thermodynamically. The obtained results showed a maximum boiling temperature azeotrope at both pressures studied. The measured equilibrium results were satisfactorily correlated by the models of Wilson, UNIQUAC, and NRTL activity coefficients. The results obtained indicate that the performance of the NRTL model is superior to the Wilson and UNIQUAC models for correlating the measured isobaric (vapour + liquid) equilibrium data.  相似文献   

16.
The recent development in the nanotechnology has paved the way for large number of new materials and devices of desirable properties which have useful functions for electrochemical sensor and biosensor applications. In this paper, a novel enzymeless glucose sensor is developed on the discovery that the FeOOH nanowire in fact possesses an intrinsic enzyme mimetic electrocatalytic activity similar to that found in natural peroxidases. The electrode modified with FeOOH nanowires showed a wide linear range (15 μM–3 mM) and high sensitivity (12.13 μA mM? 1) for glucose sensing. Other excellent performances such as highly reproducible response, long-term stability, sound mechanical and chemical stability are also observed, and the interferences of ascorbic acid and dopamine can almost be completely avoided. The good analytical performance, low cost and straightforward preparation method made this novel electrode material promising for the development of effective glucose sensors.  相似文献   

17.
Real time dissolution process of shape-controlled Pt nanoparticles (cubic, cuboctahedral, tetrahedral) has been studied using high-speed atomic force microscopy (AFM) during potential cycles in electrochemical environments. The nanoparticles are dissolved above 1.5 V(RHE) when the lower limit of the potential cycle is fixed at 0.05 V(RHE). Edges of cubic nanoparticles are dissolved at first, whereas the tops of cuboctahedral and tetrahedral nanoparticles are dissolved forming pseudo-flat structure at the upper terraces. The order of the durability is cuboctahedral < cubic < tetrahedral. When the upper limit of the potential cycle is fixed at 1.6 V(RHE), the order of the durability depends on the lower limit of the potential cycle: cubic ~ cuboctahedral < tetrahedral between 0.05 and 0.2 V(RHE), cubic < tetrahedral  cuboctahedral between 0.3 and 0.6 V(RHE).  相似文献   

18.
A series of novel 1,3,4-oxadiazole derivatives (OSD, OCOD, ONOD, OPD, COD, PMOD, and PCOD) were synthesized and characterized. Their structures were confirmed on the basis of IR, NMR and mass spectroscopy and molecular weights were found in the range 300–325 g/mol. Cancerous cell lines (MCF-7, HepG2) and non-cancerous cell lines (Chang liver cells) were treated with these compounds for 48 h, which caused dose dependent decrease in the cell viability. From the seven derivatives, OSD was found to be most potent with IC50 value close to 50 μM on all tested cell lines. Hence, this compound was selected for mechanistic study on HepG2 cell lines. Fluorescent cell staining and DNA fragmentation study of 50 μM OSD on HepG2 cells, showed events marked by apoptosis such as nuclear fragmentation, cytoplasm shrinkage and DNA damage. Further, the cells with same treatment were quantified for apoptosis using annexin V-PI flow cytometric technique. The percentage of apoptotic cells was significantly higher (p < 0.05) after OSD treatment compared to control cells. OSD induced a significant increase (p < 0.05) in the expression of the tumor suppressor p53 in HepG2 cells. The constitutive expression of anti-apoptotic protein Bcl-2 significantly decreased (p < 0.05) after treatment, while the expression of proapoptotic protein Bax significantly increased (p < 0.05). The change in Bax to Bcl-2 ratio suggested involvement of Bcl-2 family in induction of apoptosis. Furthermore, the levels of caspase-9 and caspase-3 were significantly (p < 0.05) up regulated in HepG2 cells after OSD treatment. The data suggest that 1,3,4-oxadiazole derivatives induce apoptosis mediated by intrinsic pathway of apoptosis. The findings strengthen the potential of the 1,3,4-oxadiazole scaffold OSD, as an agent with chemotherapeutic and cytostatic activity in human hepatocellular carcinoma in vitro.  相似文献   

19.
The composition of the line and band spectra of the plasma induced by a femtosecond laser pulse on the surface of sea water is determined. The temporal behaviors of the intensity of the continuum and the Ca II, Mg II and Na I lines are investigated. It is shown that the time dependence of the intensity of the Na I line is described by a monoexponential function. The characteristic decay times of the line intensities of Mg II and Na I were used to estimate the three-body recombination times. Using these values, we estimate the electron number density and the feasibility of Local Thermodynamic Equilibrium (LTE) criterion. A method involving excitation rate constants is proposed for the comparison of detection limits. For a plasma generated on a liquid surface, the following relation among detection limits will be obtained: LOD(Na) < LOD(K) < LOD(Ca) < LOD(Al) < LOD(Mg) < LOD(Zn).  相似文献   

20.
Biosynthesis of metallic silver nanoparticles (AgNPs) has gained much interest and offers an attractive alternate to physical and chemical approaches. In recent year several safe, easy, cost-effective, reproducible, and environmentally friendly synthesis approaches for silver nanoparticles have been developed. In this research work, a simple, cheap, and unexplored method was applied on green synthesis of AgNPs using secondary metabolites extracted from Bixa orellana seeds. The seeds are rich of flavonoids and phenolic compounds which presumably responsible for the fast reduction and stabilization of silver ion into silver nanoparticles. The biosynthesis process is very likely to be able to reduce silver ions under simple physiological conditions. The surface plasmon resonance (SPR) that was appeared at 420 nm in UV–vis spectrum, had confirmed the formation of AgNPs. Moreover, the functional groups in secondary metabolite that act as reducing, capping and stabilizing agents for silver nanoparticles, are identified by Fourier transform infrared (FTIR) spectra. An X-ray diffraction analysis generated four peaks for Bixa orellana seed extract mediated AgNPs positioned at 2θ angles of 38.1°, 44.2°, 64.6°, and 77.5° corresponding to crystal planes (1 1 1), (2 0 0), (2 2 0), and (3 1 1). Field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM) images confirmed the formation of nanosized silver particles. The z-average of the synthesized particles measured by dynamic light scattering (DLS) was found to be 92.9 nm. AgNPs synthesized exhibited remarkable antioxidant activity, antibacterial and antiproliferative activity against human breast (MCF-7) cell line. On the basis of our results, we conclude that biologically synthesized AgNPs exhibited favorable characteristics and have the potential to be used in biomedical fields.  相似文献   

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