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1.
Spin-lattice relaxation time measurements were made on the muscle, heart, kidneys, spleen, liver, brain and blood of both normal mice and those injected with Sarcoma-180. As well as a marked increase in the relaxation time of the tumour itself, mice injected with Sarcoma-180 showed a rise in the kidney relaxation time, along with blood relaxation times which were often either above or below the range found in normal mice. Correlation coefficients for the relaxation times of the various organs were calculated and found to be very sensitive to the physiological state of the animal. For healthy mice, the correlations were reasonably high, but even mild stress decreased the correlations, whilst the presence of cancer almost completely destroyed the correlations. These findings are all consistent with the hypothesis that cancer affects the water regulatory system of the animal as a whole.  相似文献   

2.
The 1H NMR spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and spin-lattice relaxation time in the rotating frame (T1rho) were determined for Novikoff hepatoma, Walker-256 Carcinosarcoma, Sarcoma-180 and Ehrlich Ascites tumor as well as for 7 normal tissues in the rat at 2.18 MHz. T1 values yielded improved discrimination of normal and malignant tissue compared to previous results at higher frequencies.  相似文献   

3.
本文报告从肉瘤-180小鼠腹水液中分离出抑癌因子,并将其与艾氏腹水瘤小鼠腹水中的抑癌因子进行比较。结果表明,二者具有相同的生物学特性和理化性质:1.它们均能杀伤不同的癌细胞株,但对正常细胞没有影响;2.经聚丙烯酰胺凝胶电泳,为泳动速率相同的均一多肽。  相似文献   

4.
Echitamine chloride (EC), an indole alkaloid, extracted from the bark of Alstonia scholaris has got highly promising anticancer effect. The effect of this drug on the microsomal drug detoxifying system was studied in sarcoma-180 induced mice. When given sub-cutaneously at a dosage of 5 mg/kg body weight, it was able to alter the impaired drug detoxifying system which was observed in the Sarcoma-180 bearing mice. The levels of microsomal protein, Cyt-P450, Cyt-b5, NADH-Cyt-C-reductase, NADPH-Cyt-C-reductase, and glu-6 phosphatase were determined. The levels of these drug metabolizing enzymes were decreased in S-180 bearing mice. EC treatment corrected to near normal levels of these enzymes and microsomal hemeproteins. In order to understand the mechanism responsible for the decreased protein level and its normalization after treatment with EC, 3H-Phenylalanine incorporation study was carried out. From the results, it is observed that the synthesis of apoproteins is also altered in tumor-bearing animals. All these changes which were observed in tumor-bearing animals were corrected to near normal levels after treatment with EC.  相似文献   

5.
Methylglyoxal (MG), the potent anticancer agent has been conjugated to a nontoxic, biocompatible polymer, chitosan, to protect it from in vivo enzymatic degradation. This polymeric complex, ‘Nano-MG’ shows remarkable antitumor property and elicits macrophage-mediated immunity in tumor bearing mice on intravenous (0.4 mg/kg body wt/day) treatment more efficiently than MG (20 mg/kg body wt/day). These activated macrophages appear more in numbers in the peritoneum and produce more superoxide and nitrite. Moreover, immunomodulatory cytokines and surface receptors of these macrophages like iNOS, IFN-γ, TNF-α, IL-1β, IL-6, M-CSF, TLR-4 and TLR-9 also exhibit marked up-regulation in Sarcoma-180 tumor bearing mice after Nano-MG treatment compared to untreated tumor bearing counterpart. Hence, Nano-MG acts as an immunostimulant in tumor bearing mice to combat cancer at conspicuously lower dose, probably due to its longer circulation time in blood.  相似文献   

6.
G A Ofosu  D Doakes  R Bowden  C Suggs 《Cytobios》1990,61(245):117-124
Ultrastructural studies of the effects of the chemotherapeutic agent platinum-thymine, on the morphology of sarcoma-180 ascites cells were studied to elucidate the cancer cells immediate response to therapy and the possible mode of cancer cell regression. Sarcoma-180 ascites cells treated with platinum-thymine in vitro at concentrations of 60 micrograms/ml at varying time intervals demonstrated that the drug is capable of killing cancer cells. The cells exhibited drastic nuclear and cytoplasmic alterations with few lipid spherules in the cytoplasm. The cell volume increased tremendously, with the nucleus relatively larger than the cytoplasm as time of treatment increased. Degradative features of the nucleus, and especially the nucleolus, inhibited metabolic processes. Nucleolar and cytoplasmic necrosis with increased cell volume and vacuolation are potential signals for cancer cells response to the drug and a possible mode of causing the eventual demise of the cancer cells.  相似文献   

7.
The response of the lung was studied in CFLP mice after exposure of the whole thorax to X rays (250 kVp) or cyclotron neutrons (16 MeV deuterons on Be, mean energy 7.5 MeV). To measure blood volume and leakage of plasma proteins, 51Cr-labeled red blood cells and 125I-albumin were injected intravenously and 24 h later lungs were lavaged via the trachea. Radioactivities in lung tissue and lavage fluid were determined to estimate the accumulation of albumin in the interstitial and alveolar spaces indicating damage to blood vessels and alveolar epithelium respectively. Function of type II pneumonocytes was assessed by the amounts of surfactant (assayed as lipid phosphorous) released into the lavage fluid. During the first 6 weeks, lavage protein and surfactant were increased, the neutron relative biological effectiveness (RBE) being unity. During pneumonitis at 12-24 weeks, surfactant levels were normal, blood volume was decreased, and both interstitial and alveolar albumin were increased. Albumin levels then decreased. At late times after exposure (42-64 weeks) alveolar albumin returned to normal but interstitial albumin was still slightly elevated. Values of RBE for changes in blood volume and interstitial and alveolar albumin at 15 weeks and for changes in blood volume and interstitial albumin at 46 weeks were 1.4, comparable with that for animal survival at 180 days. The results indicate that surfactant production is not critical for animal survival. They suggest that changes in blood vessels and alveolar epithelium occur during acute pneumonitis; epithelial repair follows but some vascular damage may persist. The time course of the changes in albumin levels did not correlate with increases in collagen biosynthesis which have been observed as early as 1 month after exposure and persist for up to 1 year. Furthermore, a dose which had no effect on leakage caused a marked increase in collagen biosynthesis. Thus the present results do not support a causal relationship between exudation of vascular protein during pneumonitis and the later development of fibrosis.  相似文献   

8.
Chlorella, a type of unicellular fresh water algae, has been a popular foodstuff in Japan and Taiwan. Chlorella has been shown to produce hypoglycemic effects in alloxan-induced diabetic animals. However, there are no other reports of the effects of this substance in other diabetic animal models. Here we have used streptozocin (STZ)-induced diabetic mice to study the thypoglycemic effects of Chlorella. Diabetes was induced in ICR strain mice by the i.p. injection of STZ. Vehicle-treated ICR mice were used as normal control animals and glibenclamide was used as a positive drug control. The effects of Chlorella on basal blood glucose, exogenous insulin sensitivity test and plasma insulin levels were measured. In normal mice Chlorella produced a transient hypoglycemic effect at 90 min after acute administration; whereas glibenclamide produced a more sustained hypoglycemic effect between 90 min and 180 min after acute administration. Chlorella did not affect the basal blood glucose level in STZ mice. However, Chlorella enhanced and prolonged the hypoglycemic effects of injected insulin in STZ mice for a further 60 min compared to the normal vehicle-treated group. Plasma insulin levels were increased in normal mice after treatment with glibenclamide, whereas Chlorella had no such effect. The current results indicate that Chlorella enhances the hypoglycemic effects of exogenous insulin at a dose which does not produce hypoglycemia in STZ mice, suggesting that insulin sensitivity is increased in these mice.  相似文献   

9.
Liposome encapsulation of saffron effectively enhanced its antitumor activity towards Sarcoma-180 (S-180) and Ehrlich ascites carcinoma solid tumors in mice. Significant inhibition (P < 0.001) in the growth of these tumors was observed as compared with vehicle (control) mice. In the presence of phytohemagglutinin (PHA), a T cell mitogen, saffron stimulated non-specific proliferation of lymphocytes in vitro. The intracellular reduced glutathione and related enzymes, i.e. glutathione reductase and glutathione-S-transferase, of S-180 tumor cells were significantly elevated when incubated with saffron, possibly acting to maintain functional levels of other antioxidants. Our studies indicate the antioxidant activity of saffron.  相似文献   

10.
Lipopolysaccharide of Salmonella typhimurium was irradiated with gamma radiation at 10, 15, and 30 kGy doses. A dose of 30 kGy significantly detoxified the LPS (180 times). Mice were injected intraperitoneally with the radiodetoxified LPS, and it was found that it stimulated peritoneal macrophages as was evident from the enhancement of their acid hydrolases and cellular RNA content. Both LPS and radiodetoxified LPS exhibited antitumor activity against S180 cells in Swiss mice. Treatment with 20 micrograms/mouse of either LPS or 30 kGy LPS gave maximum survival of the mice (90%). These mice were found to resist the challenge of S180 cells (1 X 10(6)).  相似文献   

11.
The arterial pH and partial pressures of oxygen (PaO2) and carbon dioxide (PaCO2) were evaluated in LAF 1 mice 15 and 38 weeks after localized irradiation of the animals' thoraxes. Graded radiation doses of 900 to 1200 rad were administered. These doses resulted in 0 to 100% lethality by 26 weeks (180 days) after irradiation. At 15 weeks after treatment mice receiving radiation doses which would subsequently result in lethality (by 180 days) exhibited significant reductions in their PaO2 and elevations in their PaCO2 values, respectively. However, there was no clear dose-response relationship between blood gas values and radiation dose, which may reflect the animals' ability to compensate for their poor blood gas exchange by an increased breathing frequency. At 38 weeks after irradiation the blood gas values were abnormal in mice from groups which had normal blood gas values at Week 15 (and no fatalities by Week 26) but in which animal deaths had occurred between Weeks 26 and 38. These data therefore indicated (i) that abnormal blood gas values occurred in the mice prior to fatalities resulting from the acute radiation pneumonitis syndrome and (ii) that mice surviving the initial radiation pneumonitis phase could still succumb to progressive pulmonary toxicity which was reflected by the increasing levels of animal lethality and altered blood gas tensions at the later times.  相似文献   

12.
Rodin VV  Foucat L  Renou JP 《Biofizika》2004,49(4):608-616
Spin-lattice relaxation and cross-relaxation in oriented and randomly oriented collagen fibers from two connective tissues (15-month-old calf and 8-year-old steer) at a water content of 0.6 g H2O/g dry matter were studied. Collagens were chosen according to different numbers of covalent nonreducible cross-links, which increase during the life of the animal. The spin-lattice relaxation curves for all the collagens after a 180 degree-tau-90 degree pulse sequence were described by two exponential components. The dependences of two components of spin lattice relaxation time and their populations on the length of the 180 degree-pulse were obtained. On the basis of data of Goldman-Shen sequence and the two-phase model, the populations of proton fractions (p(w) and p(c)) as well as the rates of transfer of magnetization between water protons and collagen protons (k(w) and k(c)) were calculated. No significant difference between k(w) (k(c)) in oriented and randomly oriented fibers as well as in fibers with different cross-linking was found. The estimates of the cross-relaxation times for low cross-link collagen and high cross-link one were done. The correlation times of dipole-dipole interactions for both connective tissues were calculated using the cross-relaxation theory.  相似文献   

13.
 We reported previously that the blood clearance of injected mouse IgG2a was extremely rapid in many strains of nude and nu/+ mice. In an attempt to determine the cause of this phenomenon, the levels of endogenous IgG2a in the blood of these mice was assayed. It was found that the serum level of IgG2a was extremely low in many of these mice, below 50 μg/ml, which is 20–100 times lower than the expected normal value. Great heterogeneity between individual mice was observed in their blood level of IgG2a, and there was an excellent correlation between low blood IgG2a levels and rapid clearance of injected IgG2a. Thus, the blood IgG2a levels are so low that a novel, previously undescribed effect occurs, namely the rapid clearance of small amounts of injected IgG2a. The clearance is due primarily to binding sites in the spleen and liver. The low level of endogenous IgG2a is not due to the lack of a thymus, since it occurs in nu/+ as well as nude mice, but can probably be attributed to the very clean environment in which these mice are raised. In assays of sera from approximately 50 mouse strains, low IgG2a levels were found in all nude colonies and also in some normal mouse strains. Some nude mice displayed relatively normal IgG2a clearance rates despite having low levels of endogenous IgG2a. In repeated bleedings of individual mice, IgG2a levels were found to fluctuate greatly. A similar clearance effect was observed with a human IgG1 Ab injected into mice. This rapid clearance of injected IgG, of certain subclasses, represents a practical problem for many experiments in which antibodies are used for diagnosis or therapy, and several methods of circumventing the problem are discussed. Received: 15 August 1977 / Accepted: 14 October 1997  相似文献   

14.
白细胞介素-18基因肌肉注射产生明显抗肿瘤作用(英文)   总被引:4,自引:0,他引:4  
 为了探讨人白细胞介素 (h IL ) - 1 8基因转导的抗肿瘤作用 ,构建了 h IL- 1 8c DNA真核表达质粒载体 pc DNA3/h IL- 1 8.将 pc DNA3/h IL- 1 8经脂质体包裹 ,按照 1 0 0μg/只的剂量注射入雄性Balb/c小鼠后肢肌肉 ,在设定时间处死小鼠取注射部位肉提取总 RNA,应用半定量反转录聚合酶链反应 (RT- PCR)及免疫组化法检测了 h IL- 1 8m RNA及其蛋白质在小鼠肌肉中不同时间点的表达水平 .随后 30只雄性 Balb/c小鼠于基因注射后第 7d腹部皮下 (i.d.)或腹腔内 (i.p.)接种 1×1 0 5个同系小鼠 S- 1 80肉瘤细胞 .观察了 S- 1 80肿瘤细胞在腹腔及皮下的生长情况、小鼠体重、肿瘤重量及存活时间 .结果发现 ,pc DNA3/h IL- 1 8注射后 2 d能检测到 h IL- 1 8m RNA表达 ,第 7d表达量较高 ,第 2 8d仍有 h IL- 1 8m RNA表达 .免疫组化染色显示了注射部位散在有 h IL- 1 8蛋白质颗粒 .h IL- 1 8基因注射组小鼠体重、肿瘤重量均比对照组轻 (P值分别小于 0 .0 0 5、0 .0 5) ,存活时间比对照组延长 .结果显示 ,真核表达系统 pc DNA3/h IL - 1 8经脂质体包裹肌注后能有效表达 ,具有明显的抑制肿瘤生长作用 .  相似文献   

15.
盐酸洛拉曲克在体内、外对S-180细胞株的抗增殖作用   总被引:2,自引:0,他引:2  
研究合合成新型胸苷合成酶抑制剂盐酸洛拉曲克在体内、外对S-180细胞株及正常人胚肾HEK293细胞的抗增殖作用;使用MTT法测定抑制率,以提高荷腹水瘤小鼠存活时间及荷实体瘤瘤重减轻情况为指标考察盐酸洛拉曲克对S-180所致肿瘤的治疗作用。结果表明:在体外盐酸洛拉曲克对S-180肿瘤细胞株有较强的细胞毒作用,对正常细胞HEK293抑制作用较弱(P<0.05);体内实验显示盐酸洛拉曲克可明显提高荷腹水瘤小鼠的存活时间,减轻荷实体瘤小鼠的瘤重,疗效与氟尿嘧啶(10mg/kg)相当(P>0.05)或更好(P<0.05)。可见,盐酸洛拉曲克在体内、外对S-180肿瘤细胞有显著的抗增殖作用,在体外对肿瘤细胞 具有选择性的抗增殖作用。  相似文献   

16.
Microbial transformation experiments were conducted with the steroidlactone, withaferin-A (1a). Cunninghamella elegans (NRRL 1393) converts withaferin-A into two major metabolites, one of which has been indentified as 14alpha-hydroxywithaferin-A (1b). The metabolite is obtained in 37% yield, and its structure was determined on the basis of pmr and mass spectral evidence. The metabolite has the same level of antitumor activity as withaferin-A against the Sarcoma-180 tumor test system in mice.  相似文献   

17.
Summary The potential for a recombinant human interleukin-2 (rIL-2, TGP-3) alone, in combination with cyclophosphamide, and in combination with cyclophosphamide and normal immunocompetent cells to manifest biological activity in vivo was tested using allogeneic, semi-syngeneic, and syngeneic tumor-host systems in mice. The biological activity of rIL-2 was evaluated by the inhibition of the growth of tumors and the inhibition of metastases in short-term assays and, in long-term assays, the prolongation of the survival time of mice bearing subcutaneously (s.c.) or intradermally transplanted tumors. rIL-2 was injected s. c. daily continuously for up to 40 days or intermittently two to four times into mice bearing established tumors. In the short-term assays, the dose and schedule dependence of activity of rIL-2 alone was significantly manifested against sarcoma 180 in ICR mice (allogeneic) by the regression of the tumor, and was confirmed against Meth-A fibrosarcoma in BALB/c mice (syngeneic) by retarding the growth of the tumor. When assessed using these tumors, it was found that the antitumor activity of rIL-2 was scheduledependent: the growth of tumors was more significantly suppressed when rIL-2 was injected every day for 10 days, starting on the 7th day after tumor transplantation, than when rIL-2 was injected five times every other day or twice every 5th day, even if the total amounts of rIL-2 injected were same. The continuous injection for 10 days was considered to be a standard regimen and the daily effective doses of rIL-2 were 5, 10, and 25 µg/mouse. Using the standard regimen and the effective doses, the activity of rIL-2 alone was also observed against two other syngeneic tumors: Colon carcinoma 26 in BALB/c mice, by retarding the growth of the tumor, and Lewis lung carcinoma in C57BL/6 mice by reducing the formation of lung metastases. When assessed using M5076 reticulum cell sarcoma, in a long-term assay, the activity of rIL-2 alone was not manifested in C57BL/6 mice (syngeneic) even when rIL-2 was injected for a long period (20 days) but it was observed in BDF1 (semi-syngeneic) mice. On the other hand, it was found that rIL-2 was effective in combination with cyclophosphamide in prolonging the survival time of C57BL/6 mice bearing the tumor. After cyclophosphamide (2.0 mg) had been administered orally to mice on the 6th day after tumor transplantation, the tumor regressed temporarily but regrew; however, when rIL-2 at a dose of 10 µg was also injected daily for a long period (40 days), the regrowth was retarded and the survival time of the mice was significantly prolonged. Moreover, when normal immunocompetent cells were transferred at the tumor sites, the regrowth of the tumors was retarded more significantly even at a daily dose of 1 µg or 3 µg rIL-2, and mice were observed to be cured by daily doses over 3 µg. The results obtained in the syngeneic tumor-host systems indicate that the continuous injection of rIL-2 is necessary and important for its activity to be manifest in vivo, and that, when combined with cytotoxic drugs and/or with immunocompetent cells, the potential efficacy of rIL-2 is valuable in cancer therapy.  相似文献   

18.
Binding of nogalamycin and adriamycin with Sarcoma-180 ascites tumor cell chromatin was studied by a spectrofluorometric method. There was significant reduction in the number of available drug binding sites per nucleotide when the chromatin was digested with DNase I for a period which releases only 7% of the chromosomal DNA. Results indicate preferential binding of these drugs with DNase I hypersensitive sites of chromatin. The DNase-I hypersensitive sites of chromatin were shown to correlate to the sequences required for gene expression. Further digestion with DNase I increases availability of drug binding sites, probably due to relaxation of the compact chromatin.  相似文献   

19.
Antineoplastic effects of carnosine (CAR) and beta-alanine (ALA), were examined in vivo using ddY mice implanted with the solid tumor Sarcoma-180. The sarcoma was treated with trypsin, 10(5) cells were implanted subcutaneously in the back of the animals, and CAR and ALA were administered subcutaneously 2 cm from the implantation site starting on the next day. The animals treated with ALA alone showed prolongation of survival to a T/C value of 132%; the growth of the tumor was inhibited and mortality reduced in those treated with CAR alone. Regression of the tumor was observed in the animals treated with either drug. The effects of these agents were enhanced when administered in combination with the non-specific active immuno-enhancing agent OK-432. More than half the animals treated with CAR and OK-432 survived the observation period (T/C greater than 218%), and survival was prolonged in those treated with ALA and OK-432 to a T/C value of 132%. The agents also showed potent antineoplastic effects on Sarcoma-180 when the tumor had been attenuated in vivo with mitomycin C (MMC).  相似文献   

20.
At later times after the injection of selenium-75-selenium methionine to CBA mice the inhibition of migration of intravenously injected normal 51Cr lymphocytes to the lymph nodes and liver lasted for a long time. On the contrary, no changes in the normal lymphocyte migration within the animal body were observed after total-body gamma-irradiation with the dose of 4 Gy. The data obtained are indicative of the radiation-induced disturbance of the microenvironment factors, which provide migration of lymphocytes within the body, during the long-term exposure to radiation emitted by the incorporated source.  相似文献   

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