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1.
Abstract The most widely used agents for photodynamic therapy are the porphyrin photosensitizers. It has been shown that hematoporphyrin derivative (HpD) can cause murine marrow hypercellularity and splenic hypertrophy. We have examined the effect on survival and marrow cellularity of high dose l,3-bis(2-chloroethyl)-l-nitrosourea (BCNU) after HpD or dihematoporphyrin ether (DHE) pretreatment in C57BL/6J mice.
The lethal toxicity of the LDS0+ 10% dose of BCNU (60 mg kg−1) was significantly reduced by pretreatment with HpD when the HpD was administered at least 3 days prior to the BCNU. HpD administered 1 or 2 days prior to BCNU or after BCNU had no effect. The percent death rate was reduced from 80 to 0% when HpD was administered 7 and 5 days prior to BCNU.
No alteration of the lethal toxicity rate of BCNU at doses of 80 mg kg−1 were identified with DHE pretreatment although some increase in median survival was noted in two groups. Some reduction in lethal toxicity was noted when 60 mg kg−1 BCNU was used and the pretreatment dose of DHE was 10 or 25 mg kg−1 given twice 3 days apart. Furthermore, a significant reduction of BCNU induced marrow cell depletion was found when low doses of DHE were used as pretreatment. High doses of DHE resulted in marrow depletion. Both HpD and DHE altered the toxicity of BCNU.
Should porphyrin photosensitizers, which alone have little toxicity, prove to protect against nitrosourea toxicity then an important dose limiting factor (myelotoxicity) could be altered if not reduction in the tumouricidal activity occurs.  相似文献   

2.
This research was dedicated to the study of the background levels of 210Po and natural gamma emitters as 40K, 214Pb, 214Bi, 228Ac, 212Pb and 212Bi in coffee powder and in coffee beverage; also the artificial 137Cs was determined. In the coffee powder the mean 210Po activity resulted 7.25 ± 2.25 × 10?2 Bq kg?1. 40K showed a mean activity of 907.4 ± 115.6 Bq kg?1. The mean activity concentration of 214Pb and 214Bi, indicators of 226Ra, given as mean value of the two radionuclides, resulted 10.61 ± 4.02 Bq kg?1. 228Ac, 228Ra indicator, showed a mean activity concentration of 13.73 ± 3.20 Bq kg?1. The mean activity concentration of 212Pb, 224Ra indicator, was 8.28 ± 2.88 Bq kg?1. 208Tl, 224Ra indicator, presented a mean activity concentration of 11.03 ± 4.34 Bq kg?1. In all samples, the artifical 137Cs resulted below the detection limit (2.0 Bq kg?1). The arithmetical mean value of percentage of 210Po extraction in coffee beverage resulted 20.5 ± 6.9. The percentage of transfer of gamma emitters,40K, 214Pb, 214Bi, 228Ac, 212Pb, 208Tl resulted of 80.0, 33.5, 24.7, 30.0, 35.1 and 53.5 % for 40K, 214Pb, 214Bi, 228Ac, 212Pb and 208Tl respectively.  相似文献   

3.
Iron(III) complexes [Fe(H2Fo4pT)Cl3] (1), [Fe(H2Ac4pT)Cl3] (2) and [Fe(H2Bz4pT)Cl3] (3) with N4 -para-tolyl-thiosemicarbazones derived from 2-formyl (H2Fo4pT), 2-acetyl (H2Ac4pT) and 2-benzoylpyridine (H2Bz4pT) were prepared and characterized. EPR data for 1–3 reveal the presence of low-spin iron(III) with d xz ²d yz ²d xy ¹ ground state. Electrochemical studies of the complexes showed mostly metal-centered redox changes with a quasi-reversible Fe(III)/Fe(II) couple. H2Fo4pT and H2Ac4pT exhibited toxicity against Artemia salina at low doses (LD50 = 27.5 µM and LD50 = 4.7 µM, respectively). Upon coordination the toxicity increased substantially in the case of [Fe(H2Fo4pT)Cl3] (LD50 = 1.9 µM) and did not change for [Fe(H2Ac4pT)Cl3]. H2Bz4pT and its iron(III) complex were not soluble in water.  相似文献   

4.
Podophyllotoxin and related analogs present numerous challenges associated with optimal antitumor activity and severe unpredictable toxicity. In an attempt to find biorational podophyllotoxin-related drug, two moieties of podophyllotoxin have been linked at C4-position by a simple modification of the carbodiimide procedure to provide novel bispodophyllotoxin analogs (4a-4e) and their structural information was extensively characterized by using 1H-NMR, IR, and HRMS.  相似文献   

5.
The adults of centipede Scolopendra cingulata from Serbia have been analyzed for 214Bi, 137Cs, 228Ac, 40K, 212Pb and 214Pb activity. The top 5 cm of soil from the same locations (Novi Pazar, Izbice and P?inja) is also measured—to estimate upper limit of the soil–S. cingulata radionuclide transfer factors (i.e., S. cingulata/soil concentration ratios), as well as the total dose rate—external and internal exposure. Cesium-137 activity was found to be below (or equal to) minimum detectable activity in all 16 specimens. The highest measured 214Bi activity was 0.1 Bq g?1, while 228Ac—0.086 Bq g?1, 40K—0.12 Bq g?1, 212Pb—0.012 Bq g?1 and 214Pb—0.029 Bq g?1. Bismut-214 transfer factors are found to range from <0.34 to 6, as 228Ac—from <0.4 to 3, whilst the total dose rate is found to be less than 18 μGy h?1. The As, Se, Cd, Co, Cr, Cu, Mn, Ni, Pb, but also Zn and Fe concentrations—in three individuals, were also determined. All the elements showed concentrations in the P?inja S. cingulata significantly lower than in S. cingulata from Novi Pazar and Izbice.  相似文献   

6.
We developed new intravenous sedative-hypnotic compounds with the isoindolin-1-one skeleton focusing on the water-soluble property and in vivo safety. We synthesized approximately 170 derivatives and evaluated their hypnotic effects by intravenous administration of the compounds to mice. A series of the 2-phenyl-3-[2-(4-methyl-1-piperazinyl)-2-oxoethyl]isoindolin-1-one analogs, 3(-), 5(-), 27(-), and 47(-) [JM-1232(-)], showed potent sedative-hypnotic activity with good water solubility and a wide safety margin. The hypnotic doses (HD50s) of these 4 compounds when administered to mice were 2.35, 1.90, 2.17, and 3.12 mg/kg, respectively, and the lethal doses (LD50s) were 88.67, 64.69, >120, and >120 mg/kg, respectively. The therapeutic indexes (LD50/HD50) were 37.73, 34.05, >55.30, and >38.46, respectively. Among these compound, 47(-) [JM-1232(-)] is being considered as the most potential candidate for clinical trials in humans.  相似文献   

7.
C57BL/6J小鼠在评价空间记忆的多T迷宫(MTM)和Barnes迷宫(BM)中表现不同,本研究拟寻找导致这种行为差异的海马蛋白.应用双向凝胶电泳结合质谱鉴定和数据库检索,分析比较经两种迷宫训练测试后小鼠海马蛋白水平的不同,发现经过BM和MTM训练的小鼠有29种蛋白表达存在明显差异.其中,在BM训练组中5种蛋白表达上调,而在MTM组中24种蛋白表达上调.与空间记忆相关的蛋白按功能可分为如下6类:(1)能量代谢相关蛋白;(2)细胞骨架相关蛋白;(3)分子伴侣;(4)神经发育相关蛋白;(5)转录因子和蛋白合成相关蛋白;(6)信号转导蛋白.本研究结果丰富了空间记忆的机制,对于神经科学的进一步发展具有启发意义.  相似文献   

8.
A simple wavelet transformation based pre-processing method is employed to minimize the duration of counting for gamma spectrometric measurements of samples from environmental matrices. Among the various forms of analyzing wavelets, a suitable one is chosen for this purpose. Measurements with 55 different counting durations were subjected to the wavelet based processing and results were compared with long duration counting time measurements of 40K, 137Cs, radionuclide from 238U series (214Bi, 214Pb) and 232Th series (228Ac, 212Bi, 212Pb, 208Tl). It is observed that with a proper choice of the wavelet function a tenfold reduction in counting duration can be achieved with errors <5 %.  相似文献   

9.
The present paper includes synthesis and spectral characterization of the novel prepared palladium(II) and zinc(II) complexes with 2-formyl pyridine N(4)-1-(2-pyridyl)-piperazinyl thiosemicarbazone, HFo4Npypipe, 1 and the 2-acetyl pyridine N(4)-1-(2-pyridyl)-piperazinyl thiosemicarbazone, HAc4Npypipe, 2. The Pd(II) complexes [PdCl(Fo4Npypipe)], 3, [PdCl(Ac4Npypipe)], 4 and the Zn(II) complexes [ZnCl2(Fo4Npypipe)], 5 and [ZnCl2(Ac4Npypipe)], 6 have been characterized by elemental analyses and spectroscopic studies. The crystal structure of the complexes [PdCl(Fo4Npippy)], 3 and [PdCl(Ac4Npippy)], 4, have been solved by single-crystal X-ray diffraction. The electronic, IR, UV/Vis, and NMR spectroscopic data of the complexes are reported. The results of the cytotoxic activity of 16 have been evaluated in vitro against the cells of three human cancer cell lines: MCF-7, T24, A-549 and a mouse L-929 (a fibroblast-like cell line cloned from strain L). For selected compounds 2 and 6 the acute toxicity and antitumor activity were evaluated on leukemia P388-bearing mice. The Zn(II) compounds 5 and 6 are considered as agents with potential antitumor activity, and can therefore be candidates for further stages of screening in vitro and/or in vivo.  相似文献   

10.
New platinum complexes have been synthesized by the reaction of Na2PtCl4 with 2-acetylpyridine-4-cyclohexyl-thiosemicarbazone, HAc4CyclHexyl (1). The new complexes [Pt(Ac4CyclHexyl)Cl] (2) and [Pt(Ac4CyclHexyl)2] (3) have been characterized by elemental analyses and spectroscopic studies. The crystal structure of the complex [Pt(Ac4CyclHexyl)Cl] · DMF has been solved by single-crystal X-ray diffraction. The anion of Ac4CyclHexyl coordinates in a planar conformation to the central platinum(II) through the pyridyl N, azomethine N and thiolato S atoms. The crystal packing is determined by double intermolecular hydrogen interactions, π–π, Pt–C and Pt–π contacts. The cytotoxic activities of 13 have been evaluated for antiproliferative activity in vitro against the cells of three human cancer cell lines: MCF-7 (human breast cancer cell line), T24 (bladder cancer cell line), A-549 (non-small cell lung carcinoma) and a mouse L-929 (a fibroblast-like cell line cloned from strain L). The compounds 13 display IC50 values in a μM range better than that of the antitumor drug cisplatin and are considered as agents with potential antitumor activity candidates for further stages of screening in vitro and/or in vivo.  相似文献   

11.
氟化钠对小鼠的急性毒性实验研究   总被引:1,自引:1,他引:0  
为探讨氟化钠对小鼠的急性毒性及反应,采取灌胃法给小鼠一次性给药,观察了7 d内35.00、55.56、88.18、139.97、222.18、352.67、559.79 mg/kg等7个剂量组小鼠的毒性反应和死亡情况,计算了氟化钠经口半数致死量(LD50)及95%可信限.结果表明,各剂量组中毒小鼠均出现不同程度的抽搐、...  相似文献   

12.
Immunosuppressive activity of 8-gingerol on immune responses in mice   总被引:2,自引:0,他引:2  
8-gingerol is one of the principal components of ginger, which is widely used in China and elsewhere as a food, spice and herb. It shows immunosuppressive activity on the immune responses to ovalbumin (OVA) in mice. In the present study, we found that 8-gingerol suppressed lipopolysaccharide (LPS) and concanavalin A (ConA)-stimulated splenocyte proliferation in vitro. In vivo, 8-gingerol not only signi?cantly suppressed Con A-, LPS- and OVA-induced splenocyte proliferation (P < 0.05) but also decreased the percentage of CD19+ B cells and CD3+ T cell (P < 0.05) at high doses (50, 100 mg/kg). Moreover, OVA-speci?c IgG, IgG1 and IgG2b levels in OVA-immunized mice were reduced by 8-gingerol at doses of 50, 100 mg/kg. These results suggest that 8-gingerol could suppress humoral and cellular immune responses in mice. The mechanism might be related to direct inhibition of sensitized T and B lymphocytes.  相似文献   

13.
With the importance of mouse as a model to study human diseases and the human and rat plasma/serum two-dimensional (2-D) maps being extensively annotated, this study was aimed at constructing a detailed mouse serum 2-D map. Serum proteins from two different inbred strains of mice (BALB/cJ and C57BL/6J) and mice subjected to two different inflammatory stimuli (20% burn injury and lipopolysaccharide (LPS) injection) were separated on overlapping gels covering pH 3-8 and stained with SYPRO Ruby dye. The tryptic peptides from the resolved spots were analyzed by mass spectrometry, leading to the identification of 38 different gene products. With the exception of major urinary proteins found in abundance in male C57BL/6J mice, little strain difference of the mouse serum 2-D was observed. Many proteins detected in the mouse serum 2-D map were not reported in human or rat serum 2-D maps including epidermal growth factor receptor. Three major murine acute-phase proteins (APPs), haptoglobin, serum amyloid A, and serum amyloid P, were highly induced by both inflammatory stimuli. Image analysis shows that the variations of APPs between these two inflammatory models were not uniform although LPS (100 microg/animal) in general was more effective than 20% burn injury in inducing APPs. Serum amyloid A, much more sensitive to endotoxin than burn injury, may represent a sensitive marker to differentiate these two different inflammatory states.  相似文献   

14.
The natural background gamma (NBG) spectrum was accumulated inside the laboratory, with 102.88 cm3 Ge(Li) detector, to investigate bismuth natural radionuclides in the energy range of 500–1700 keV. The relative intensities of identified214Bi gamma lines were obtained from the spectrum. The results were in good agreement with that obtained from a source of a precise strength. Out of the 25 gamma lines of214Bi, 19 lines were established including 6 lines observed for the first time in the NBG spectrum. Most of the gamma lines of211Bi and212Bi were observed. Some of these lines are new.  相似文献   

15.
Synthesis of delta-aminolevulinic acid (ALA) derivatives is a promising way to improve the therapeutic properties of ALA, particularly cell uptake or homogeneity of protoporphyrin IX (PpIX) synthesis. The fluorescence emission kinetics and phototoxic properties of ALA-n-pentyl ester (E1) and R,S-ALA-2-(hydroxymethyl) tetrahydrofuranyl ester (E2) were compared with those of ALA and assessed on C6 glioma cells. ALA (100 micrograms/mL), E1 and E2 (10 micrograms/mL) induced similar PpIX-fluorescence kinetics (maximum between 5 and 7 h incubation), fluorescence being limited to the cytoplasm. The 50% lethal dose occurred after 6 h with 45, 4 and 8 micrograms/mL of ALA, E1 and E2, respectively. ALA, E1 and E2 induced no dark toxicity when drugs were removed after 5 min of incubation. However, light (25 J/cm2) applied 6 h after 5 min incubation with 168 micrograms/mL of each compound induced 85% survival with ALA, 27% with E1 and 41% with E2. Increasing the incubation time with ALA, E1 and E2 before washing increased the phototoxicity, but E1 and E2 remained more efficient than ALA, regardless of incubation time. ALA-esters were more efficient than ALA in inducing phototoxicity after short incubation times, probably through an increase of the amount of PpIX synthesized by C6 cells.  相似文献   

16.
Qiao Q  Li T  Sun J  Liu X  Ren J  Fei J 《Talanta》2011,85(1):718-724
Previous studies have shown that the C57 and 129 strains of mice display marked differences in behavioural performance, neuroanatomy, neurochemistry and synaptic plasticity. However, few metabolomic studies of their biofluids have been performed. As part of a series of metabolic phenotyping, the effects of gender and strain upon serum metabolite composition and variation are examined in this study using gas chromatography-mass spectrometry (GC-MS) in normal C57BL/6J and 129S1/SvImJ strains of mice. The 129S1/SvImJ strain is phenotypically distinct from the C57BL/6J strain and characteristic metabotypes are produced for both male and female mice of each strain. These data demonstrate that the C57BL/6J and 129S1/SvImJ strains of mice show a wide range of metabolic differences across glycine, serine and threonine metabolism; valine, leucine and isoleucine biosynthesis; and tricarboxylic acid cycle pathways. Remarkably, the concentration of glyceric acid in the 129S1/SvImJ strain is significantly increased compared to the C57BL/6J mouse strain, reflecting important considerations for studies that use the 129S1/SvImJ mouse as the human d-glycericaciduria model. We infer that a deficiency of d-glycerate kinase would explain such a glyceric acid accumulation in the 129S1/SvImJ strain. More importantly, this differential metabolite level data provide insight into specific metabolic pathways and lay the groundwork for integrated studies of the mouse models.  相似文献   

17.
水溶性煤基酸分为从含有水溶性煤基酸的低价煤中抽提得到的水溶性煤基酸和从不含有水溶性煤基酸的低阶煤中氧化得到的水溶性煤基酸。考察了从武川风化煤和霍林河风化褐煤通过两步催化氧化法得到的水溶性煤基酸和从晋城风化煤中得到的水溶性煤基酸对高效、高毒性的杀虫剂--久效磷生物活性的影响。结果表明:(1)三种煤基酸都能增加久效磷的生物活性;(2)所用水溶性煤基酸的理想浓度为0.0025%;(3)根据毒力曲线,久效磷、武川煤基酸-久效磷和霍林河-久效磷的致死中浓度为9.94g/ha,5.99g/ha,6.62g/ha,相对毒力系数分别为:100,165.9,150.2;(4)大田实验结果证实了水溶性煤基酸对久效磷的增效作用。  相似文献   

18.
Summary The activities of218Po,214Po and211Bi were determined in samples obtained of soil/gas. Sampling work was taken in Jáchymov (Czech Republic) at the outcrop of the Geister-vein,by electrostatic precipitation from filtered soil gas on stainless steel disks.The samples were measured in a field laboratory using a semi-conductor alpha-spectrometer.The activities of218Po,214Po and211Bi were calculated.Samples taken from active dump material (near-by radon source) exhibited a high211Bi/214Po ratio, while those of the vein outcrop (a relatively deeper source) had a low ratio.A mathematical model was employed to determine the radon age calculated from the actinon/radon input ratio.This varied in a range of 5.6 to -7.7 seconds.Negative age values are probably caused by the preference for actinon, which rapidly comes into equilibrium with the source of this gas.  相似文献   

19.
Rapid determination of 222Rn and 220Rn progeny (214Pb, 212Pb, 214Bi, 212Bi) is achievable using manganese dioxide (MnO2) precipitation with analysis by γ-spectrometry. This is of interest to environmental monitoring programmes that utilise gross activity methods to screen for anthropogenic radionuclides. The contribution from these naturally occurring radionuclides (NOR) varies, and is difficult to experimentally measure due to short half-lives (t ½ = 19.9 m–10.64 h) and low environmental activity (<0.1 Bq L?1). The extraction efficiency of the technique is above 90%, and above 80% for other nuclides (232Th, 238U, 235U, 228Ac, 226Ra, 224Ra, 210Pb, 54Mn). Short-lived NOR have been measured at two surface water locations, and indicates elevated 214Bi activity of 4.0 ± 1.1 Bq L?1.  相似文献   

20.
A model system was characterized for investigating the potential role of cortisol in MTB induced immunopathology. Serum cortisol levels were evaluated in two mouse strains; C57BL/6 mice develop lung granulomas following acute Mycobacterium tuberculosis infection while A/J mice are deficient in this process. Serum cortisol levels were examined post infection, as well as immunoregulatory mRNA expression in the lung, measured using bioluminescent RT-PCR techniques. Prior to infection, the A/J mice constitutively maintain nearly 75&percent; higher serum cortisol than C57BL/6 mice. Both A/J and C57BL/6 mice exhibited approximately 30&percent; reduction in relative serum cortisol following infection. At no time did serum cortisol levels in the A/J fall below constitutive levels in the non-infected C57BL/6. The overall elevated cortisol in the A/J may affect pulmonary immunoresponsiveness; A/J mice exhibited earlier induction of IL-10 and TNF-alpha than C57BL/6 mice, with a relative lack of IL-2 during late infection. Conversely, the C57BL/6 mice demonstrated higher IL-12(p40) and IL-2 messages at the latter stages of disease than the A/J mice. Both mice demonstrated high IFN-&gama; mRNA. The high constitutive serum cortisol in the A/J mice may therefore contribute to establishment of an environment counter-productive to initiation of protective Th1 cell and granulomatous responses.  相似文献   

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