Antitumor activity of Nitronaphthal-NU, a novel mixed-function agent

Nitronaphthal-NU (Compound 1) was synthesized as a mixed-function antitumor agent based on the structures of the clinical drug CCNU and experimental compound Mitonafide. In vitro screening in four human tumor cell lines namely SNB-78 CNS, HOP-62 Lung, T47D Breast and SiHa - cervix revealed significant cytotoxicity in the former two cell lines much greater than CCNU and comparable to Mitonafide used as standards. In vivo antitumoral potency assessed in the murine ascites tumors Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times of drug treated (T) over untreated control (C) mice, revealed highly significant (p<0.001) tumor regression effects greater than standards. Life span of mice bearing advanced tumor for 10 days before the drug challenge was also considerably increased. Its toxicity was assessed in vivo in normal and S-180 bearing mice by measuring drug-induced changes in haematological parameters, femoral bone marrow and splenic cellularities as well as hepatotoxicity and nephrotoxicity sequentially on days 9, 15 and 21 following drug treatment at the optimum dose of 50 mg/kg from day 1 to 7. Results indicate that it did not adversely affect haematopoiesis. The other parameters were within normal limit. The compound comparable to standards inhibited the synthesis of DNA and RNA in S-1 80 tumor cells.     

Evaluation of naphthal-NU,a 2-chloroethylnitrosourea derivative of naphthalimide,as a mixed-function anticancer agent

Naphthal-NU, 2-[2-[3-(2-chloroethyl)-3-nitrosoureido]ethyl]-1H-benz[de]isoquinoline-1,3-dione (Compound 1) has been synthesized as a rationally designed new mixed-function anticancer agent from 1,8-naphthalic anhydride. Its chemical alkylating activity compared with CCNU as standard compound indicated that it possesses greater alkylating activity than the latter. Its antitumour efficacy was assessed in vivo in two murine ascites tumours namely Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times (MST) of drug treated (T) over untreated control (C) mice. Three clinical drugs namely CCNU (lomustine), endoxan (cyclophosphamide) and 5-fluorouracil (5-FU) were used as positive controls for comparison. Compound 1 has displayed excellent and reproducible antitumoural activity having curative effects in these tumours comparable with CCNU and 5-FU. It has also significantly increased the life span of mice bearing highly advanced tumour for 10 days before the drug challenge. Its toxicity was also assessed in vivo in normal and in S-180 bearing mice by measuring drug-induced changes in hematological parameters, femoral bone marrow and splenic cellularity sequentially on days 9, 15 and 21 following drug treatment at the optimum dose of 50 mg/kg from day 1 to 7. The results indicated that the compound did not adversely affect hematopoiesis. Drug-induced hepatotoxicity and nephrotoxicity were also evaluated at its optimum dose on those days but no such toxicities were detected. It was further screened in vitro in 6 different human tumour cell lines but no significant activity was observed in those lines.     

Evaluation of dimethoxydop-NU as a novel anti-tumor agent

Dimethoxydop-NU, 1-[2-{3-(2-Chloroethyl)-3-nitrosoureido}ethyl]-3,4-dimethoxy-benzene (Compound 1), was synthesized from 3,4-dimethoxy-phenethylamine as a novel anti-tumor agent based on the structures of the clinical drug CCNU and dopamine, an important endogenous biological amine having anti-angiogenesis property. In vitro screening in two human tumor cell lines, namely promyelocytic leukemia HL-60 and histiocytic lymphoma U-937, revealed its cytotoxicity greater than that of hydroxyurea and comparable to BCNU used as standards. Its in vivo anti-tumoral potency was assessed in the murine ascites tumors Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times of drug treated (T) over untreated control (C) mice. Results revealed significant tumor regression effects in these tumors. The survival time of treated mice was markedly increased by combination of the compound 1 with dopamine hydrochloride. Its toxicity was assessed in vivo in normal and EAC bearing mice by measuring drug-induced changes in hematological parameters, femoral bone marrow and splenic cellularities as well as biochemical parameters sequentially on days 9, 14 and 19 following drug treatment at the optimum dose of 30 mg/kg from day 1 to 7. Results indicated that initial suppression in the femoral bone marrow cellularity seen on day 9 reached normalcy by day 19. Other parameters were within normal limit. Histopathological studies of liver revealed mild hepatotoxicity on day 9 in treated groups that substantially recovered on day 19. Similar studies with heart and kidney revealed no cardio toxicity or nephrotoxicity. Compound 1 comparable to standards inhibited the synthesis of DNA and RNA in S-180 tumor cells.     

Evaluation of naphthalmustine, a nitrogen mustard derivative of naphthalimide as a rationally-designed anticancer agent

Naphthalmustine, 2-[2-[bis-(2-chloroethyl)amino]ethyl]-1H-benz[de]isoquinoline-1,3-dione (Compound 1) has been synthesized as a rationally designed new anticancer agent from N-(2-bromoethyl)naphthalimide. Its chemical alkylating activity exceeded that of nor-HN2 used as standard compound for comparison. Its antitumour efficacy was assessed in vivo in two murine ascites tumours namely Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times (MST) of drug treated (T) over untreated control (C) mice. The clinical drug cyclophosphamide and the experimental compound mitonafide were used as positive controls for comparison. Compound 1 has displayed substantial and reproducible antitumoural activity in these tumours since very high remission times of treated animals were observed. Significant increase in the life span of mice bearing highly advanced tumour for 10 days before the drug challenge was also noted after its treatment. Its LD50 value was 200 mg/Kg by single i.p. injection. Its toxicity was also assessed in vivo in normal and in S-180 bearing mice by measuring drug-induced changes in hematological parameters, femoral bone marrow and splenic cellularity sequentially on days 9, 15 and 21 following drug treatment at the optimum dose of 12 mg/kg from day 1 to 7. The results indicated that the compound did not adversely affect hematopoiesis. Drug-induced hepatotoxicity and nephrotoxicity were also evaluated on those days but no such toxicities were detected. Naphthalmustine inhibits the synthesis of DNA and RNA in S-180 tumour cells. It was further screened in vitro in 4 different human tumour cell lines but no significant activity was observed in those lines.     

Evaluation of dimethylaminosulfonates of alkane diols as a novel group of anticancer agents

A series of title compounds has been synthesized and evaluated by the cytotoxicity assays conducted in vitro in seven human tumor cell lines, initially in MT-4 and H-9, followed by U-937, PM-1, MCF-7, Hep-3B, and K-562. These compounds were simultaneously compared with the existing clinical drug, busulfan and also with an experimental drug, hepsulfam. IC(50) values of these agents in T-cell lymphoma and leukemic cell lines indicate that two of these agents hexsulfamyl and octsulfamyl (compounds 3 and 4) were significantly more potent than busulfan and were comparable in antileukemic activity with hepsulfam. In order to determine the effect of these agents on normal proliferating cells, the toxicity of 3 and 4 was also determined in vitro against human peripheral blood mononuclear cells (PBMC) and against murine bone marrow progenitor cells. PBMC assay data indicate that these agents were generally less toxic than hepsulfam. The results of the colony forming unit-erythroid (CFU-E) and granulocyte-macrophage colony forming unit (CFU-GM) assays, however, indicate that these agents were more toxic than hepsulfam to erythroid progenitor cells than to granulocyte-macrophage progenitors. The toxicity of octsulfamyl was further assessed in vivo in normal Swiss mice by measuring drug-induced changes in hematological parameters, femoral bone marrow cellularity and splenic cellularity as well as hepatotoxicity and nephrotoxicity on day 7 and 14 following drug treatment at the dose of 1.0 mg/kg body weight from days 1 to 5. The results indicate that the compound did not adversely affect hematopoiesis. Marginal bone marrow suppression was observed on day 7, which gradually tends to reach normalcy on day 14. The other parameters were within normal limit.     

Residual toxicity in hematopoietic cells following a single dose of methylnitrosourea

The residual injury to the proliferation capability of hemopoietic stem cells (CFU-S) which results from their exposure to leukemogenic agents was evaluated in mice given a single leukemogenic dose of methol nitrosourea (MNU 50 mg/kg body weight, i.v.). Bone marrow cellularity, splenic weight, number of CFU-S and the proportion of cycling to noncycling CFU-S were measured in an effort to detect acute and residual injury to the CFU-S from mice given MNU 21 and 3 days earlier. Marrow cells were also transferred into lethally irradiated mice to observe the self-renewal capability of the CFU-S in the recipient spleen and bone marrow. The results of these measurements show that the CFU-S in marrow from mice given 50 mg/kg of MNU 21 days earlier still have a defective ability for self-renewal, although the total cellularity, number of CFU-S and proportion of cycling and noncycling CFU-S in the donor have returned to the normal range. The relationship of this self-renewal defect to the development of leukemia after this leukemogenic dose of MNU is not known.     

Evaluation of beta-tethymustine, a new anticancer compound, in murine tumour models

beta-Tethymustine, 1-[2- {bis(2'-chloroethyl)amino}ethyl]spiro[imidazolidine-4,2'-(1'H),3',4'-dihydronaphthalene]-2,5-dione, has been synthesised and LD50 value determined in Swiss male mice, which was found to be 100.00 mg/kg by single i.p. injection. The following three criteria, namely ascites cell count, ascites fluid measurement and increase in median survival times (MST) of drug-treated (T) over untreated control (C) mice, were studied for evaluation of its antitumour efficacy in vivo in three murine ascites tumours, namely Ehrlich ascites carcinoma (EAC), sarcoma-180 (S-180) and Dalton's lymphoma (DL). At the optimum dose range of 8.0 mg/kg (higher) to 4.0 mg/kg (lower) for 1-7 days treatment following tumour transplantation on day 0, it exhibited a very high percentage of inhibition of both the ascites cell and fluid in these models and displayed excellent ILS(max) value of 80 in EAC, 224 in S-180 and 240 in DL, respectively, showing 'curative' effect (2-3/6 mice having 90 days survival rate). It also demonstrated a high ILS value of 150 with one cure/six mice bearing S-180 for 6 days prior to drug therapy. Screening results were compared with two clinical drugs, cyclophosphamide and 5-fluorouracil, serving as positive controls. Its chemical alkylating activity was compared with nor-HN2 (NSC 10873) and spiromustine (NSC 172112). The results indicate that it possesses greater alkylating activity than nor-HN2 and comparable activity with spiromustine.     

The triterpenoid fraction from Trichosanthes dioica root exhibits antiproliferative activity against Ehrlich ascites carcinoma in albino mice: involvement of possible antioxidant role

The present study assessed the triterpenoid fraction from T dioica root (CETD) for antiproliferative effect and antioxidant influence against Ehrlich ascites carcinoma (EAC) in Swiss albino mice. Twenty-four hours after intraperitoneal inoculation of tumor (EAC) cells in mice, CETD was administered at 2 and 4 mg/ kg body weight daily for 9 consecutive days. On the 10th day, half of the mice were sacrificed for estimation of tumor proliferation, haematological, and hepatic antioxidative parameters viz. lipid peroxidation, reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase(SOD)and catalase (CAT); the rest were kept alive for assessment of survival parameters. The antiproliferative effect of CETD was assessed by evaluating tumor weight, tumor volume, packed cell volume, viable and non-viable tumor cell counts, mean survival time and percentage increase in life span of EAC-bearing mice. CETD exhibited dose dependent and significant (p < 0.001) decreases in tumor weight, tumor volume, packed cell volume and viable cell count and extended the life span of EAC-bearing mice. Hematological profiles were significantly (p < 0.001) normalized in CETD treated mice as compared to EAC control. CETD treatment significantly (p < 0.001) modulated the aforementioned hepatic antioxidative parameters as compared to EAC control. The present study demonstrated that CETD possessed promising antiproliferative efficacy against EAC in mice, plausibly mediated by alleviation of oxidative stress by multiple mechanisms.     

Effects of prenatal irradiation on fetal, neonate, and young adult murine hemopoiesis

B6D2F1 mice received cobalt-60 radiation on day 10.5 of gestation at doses of 50 to 300 rad at a dose rate of 40 rad per min. These animals were studied at four selected age periods: (a) day 14.5 of gestation, (b) neonate, (c) juvenile, and (d) 13 week-old adult. Fetal liver cellularity, morphology, and hemopoietic progenitor cell concentration reflected injury after 200 rad. The 15 day-old mouse spleen cellularity was affected more than bone marrow cellularity, but greater radiation injury was reflected by bone marrow hemopoietic progenitor cells. Fluctuations from normal hematopoietic values were greater in the 15 day-old juvenile than in the 9 day-old neonate, commencing with 50 rad. These included peripheral blood parameters and marrow- and spleen-derived erythroid-, granulocytic- and megakaryocytic-progenitor cells. The consequences of prenatal irradiation (150 rad) were evident in the 13 week-old mouse. This was manifested by a reduced spleen cellularity and perturbations in concentrations of hemopoietic progenitor cells in the bone marrow.     

Anti-tumor effects of recombinant human macrophage colony-stimulating factor, alone or in combination with local irradiation, in mice inoculated with Lewis lung carcinoma cells

Recombinant human (rhu) macrophage colony-stimulating factor (M-CSF) was evaluated for efficacy, either alone or in combination with local X-irradiation (LR), in mice inoculated subcutaneously (s.c.) with Lewis lung carcinoma (LLC) cells. The size of the primary tumor and numbers of lung metastases, 21 days after tumor inoculation and 15 days after the start of treatment, were reduced by 87% in tumor-bearing mice treated with 20 micrograms/dose M-CSF s.c. twice a day for 5 days. LR (800 cGy) to the tumor once a week for 2 weeks had a moderate anti-tumor effect and enhanced the anti-tumor effect of M-CSF. Hematological parameters, including nucleated cellularity in peripheral blood, femoral marrow, spleen and peritoneal exudate, as well as marrow and splenic granulocyte-macrophage progenitor cells, and numbers of splenic Thy 1.2+ cell and peritoneal mast cells, were perturbed in LLC-bearing mice, and were influenced by treatment with M-CSF and LR. Treatment with M-CSF plus LR, but not with either agent alone, was associated with a significant, although slight, enhancement in survival time for LLC-bearing mice. Inability to obtain a better survival-enhancing effect appeared to be related to the limited treatment, since the anti-tumor effects of M-CSF were more notable early on in disease progression and were related to the dose of M-CSF used. The effects of M-CSF were most probably indirect ones on the host immune system. M-CSF, in combination with LR, may be of benefit in the treatment of human tumors that have metastatic potential.     

血液病骨髓动态增强MRI特征的初步研究

目的探讨血液病患者骨髓动态增强MRI(DCE-MRI)与骨髓细胞构成的关系。方法对25例恶性血液病患者进行DCE-MRI检查,测定骨髓灌注的最大强化率(PER)、最大强化斜率(Slopemax)、峰值时间(TTP)和平均时间(MT);30 min后进行髂嵴穿刺活检,分析细胞构成。结果25例血液病患者中,正常细胞数型骨髓20例,细胞数增多型骨髓3例,细胞数减少型骨髓2例。DCE-MRI骨髓时间-信号强度曲线(TIC)B型3例,C型7例,D型13例,E型2例。细胞数增多型骨髓PER、Slopemax均高于正常细胞数型骨髓和细胞数减少型骨髓;细胞数增多型骨髓TTP短于正常细胞数型骨髓和细胞数减少型骨髓;细胞数减少型骨髓MT短于正常细胞数型骨髓和细胞数增多型骨髓。结论DCE-MRI可以作为无创、有效监测血液病骨髓细胞构成变化的手段之一。     

Antitumour activity of saffron (Crocus sativus)

Antitumor activity of saffron (Crocus sativus) extract a commonly used spice in India was studied against intraperitoneally transplanted sarcoma-180 (S-180), Ehrlich ascites Carcinoma (EAC) and Dalton's lymphoma ascites (DLA) tumours in mice. Oral administration of 200 mg/kg body weight of the extract increased the life span of S-180, EAC, DLA tumour bearing mice to 111.0%, 83.5% and 112.5%, respectively. The same extract was found to be cytotoxic to P38B, S-180, EAC and DLA tumour cells in vitro. Thymidine uptake studies indicated the mechanism of action of the extract at the site of DNA synthesis. Toxicity studies showed that the hematological and biochemical parameters were within normal range. These results indicate the potential use of saffron as an anticancer agent.     

Cytotoxic and antitumour principles from Ixora coccinea flowers

The antitumour activity of Ixora coccinea L. (Rubiaceae) flowers was studied in comparison to intraperitoneally transplanted Dalton's lymphoma (ascitic and solid tumours) and Ehrlich ascites carcinoma (EAC) tumours in mice. Intraperitoneal administration of 200 mg/kg of the active fraction (AF) of the I. coccinea flower increased the life-span of DLA and EAC ascitic tumour-bearing mice by 113 and 68%, respectively. The AF showed less activity against solid tumours (DLA) as compared to ascitic tumours. The same active fraction showed 50% cytotoxicity to DLA, EAC and Sarcoma-180 (S-180) cells in vitro at concentrations of 18, 60 and 25 μg/ml, respectively. It was not toxic to normal lymphocytes, whereas it was toxic to transformed lymphocytes from leukaemic patients, acute lymphoblastic leukaemia (ALL) and chronic myelogenous leukaemia (CML) and K-562 suspension cell cultures. The AF inhibited tritiated thymidine incorporation in cellular DNA.     

Cyclophosphamide 24 hours before or after total body irradiation: effects on lung and bone marrow

Preparative regimens for bone marrow transplantation (BMT) use a sequence of drugs, such as cyclophosphamide, in combination with radiation. However, the optimum sequencing of the two agents that will maximize tumor cell kill and minimize normal tissue damage is unknown and controversial. The studies presented here were done in order to determine the effect of cyclophosphamide on bone marrow and lung damage in mice when given 24 h before or after total body irradiation (TBI). A range of single doses of TBI was given before or after a single sublethal dose of 180 mg/kg of cyclophosphamide. The bone marrow of all mice intended for lung damage assessment was reconstituted with 5 x 10(6) syngeneic bone marrow cells. Lung damage was assessed by breathing rate and lethality; bone marrow damage by lethality at 30 days. LD50 values for pneumonitis were obtained between 30 and 84 days after cyclophosphamide and radiation and between 80 and 180 days after radiation alone. Dose modifying factors were obtained as the ratio of LD50s for mice given only TBI compared to those for mice given cyclophosphamide and TBI. Cyclophosphamide enhanced radiation pneumonitis when given before or after TBI, giving DMFs of 1.4 and 1.2 (1.1-1.4, 95% c.l.) respectively. The effect of cyclophosphamide on radiation pneumonitis was drug dose-dependent. The LD50 for death from bone marrow damage was reduced when cyclophosphamide was given either before or after TBI but the effect was greater, i.e. the LD50 was lower when cyclophosphamide was given after TBI. These data show that cyclophosphamide given 24 h after TBI causes less lung damage but more bone marrow damage in this mouse model.     

Haematopoietic late effects of prolonged bleomycin treatment in mice

Summary In two studies, haematopoietic late effects of prolonged bleomycin treatment were evaluated in mice given serial injections of 21 mg bleomycin/m² weekly for 31 and 44 weeks, respectively. Femoral bone marrow cellularity measured at 43, 45, and 49 weeks after discontinuation of the drug in the first and after 20 weeks in the second study was found to be significantly (P<0.05) lower in the treated mice than in the controls. CFU-S, BFU-E, and CFU-C contents were also reduced in the treated bone marrow, but with the exception of CFU-S in the second study, differences from control values were not significant. Additional long-term bone marrow cultures performed in the second study revealed no marked changes in the marrow proliferative activity and the self-renewal of stem cells to explain the reduced marrow cellularity and stem cell content. These last findings might, therefore, be due to a decrease in femoral size with less marrow content in the treated mice, since measurements of the tibial weights in both groups showed that the bones in the treated animals were significantly (P<0.05) lighter than those in the controls.     

Gossypol inhibits Ehrlich ascites tumor cell proliferation

Neutral gossypol solution injected peritoneally into NMRI mice preimplanted with Ehrlich ascites tumour cell, at a dose of 25–100 μg/mouse per day, lengthened the number of survival days of the hosts. This gossypol effect on tumour cell proliferation is concentration dependent. The optimum dose is 100 μg. However, at too high a dose, the gossypol caused a body weight loss and the death of the tumour-bearing mice.     

Minimally-invasive debulking of ovarian cancer in the rat pelvis by means of photodynamic therapy using the pegylated photosensitizer PEG-m-THPC

Interstitial photodynamic therapy (PDT) using the pegylated photosensitizer PEG-m-THPC was evaluated as a minimally-invasive procedure to selectively debulk unrespectable pelvic ovarian cancer (NuTu-19) in immunocompetent rats. To assess tumour selectivity, PEG-m-THPC at dosages of 0.3, 3.0 and 30 mg kg(-1) body weight was administered intravenously to 30 rats 4 weeks following tumour induction. Eight days later laser light at 652 nm and optical doses ranging from 100 to 900 J cm(-1) diffuser-length was delivered by an interstitial cylindrical diffusing fibre inserted blindly into the pelvis. Three days following light application, the volume of necrosis was measured and the damage to pelvic organs was assessed histologically on cross sections. For analysis of survival, 20 tumour-bearing rats received PDT using drug doses of 3 or 9 mg kg(-1) body weight and an optical dose of 900 J cm(-1) diffuser-length, whereas ten untreated tumour-bearing rats served as controls. The histological assessment of PDT induced necrosis showed a non-linear dose-response for both the photosensitizer dose and the optical dose. The lowest drug dose activated with the highest optical dose did not induce more necrosis than seen in tumour-bearing control animals. The same optical dose induced necrosis of 17 mm in diameter using 30 mg kg(-1) and 11 mm using 3 mg kg(-1) photosensitizer. The optical threshold for induction of significant necrosis was between 100 and 300 J cm(-1) diffuser-length for 30 mg kg(-1) and between 300 and 500 J cm(-1) for 3 mg kg(-1) PEG-m-THPC. Significant damage to normal pelvic organs was only seen if 30 mg kg(-1) photosensitizer was activated with optical doses of 700 J cm(-1) or more. In the survival study, all treated animals survived PDT for at least 2 weeks and the intestinal and urinary tract remained functional. No clinical signs of blood vessel or nerve injury were observed. Mean overall survival of untreated tumour-bearing rats was 25.0 +/- 4.5 days compared to 38.4 +/- 3.8 days and 40.0 +/- 3.6 days for rats treated with 3 mg kg(-1) or 9 mg kg(-1) PEG-m-THPC mediated PDT respectively (P < 0.05). We conclude that PEG-m-THPC mediated PDT has a favourable therapeutic window and that this minimally-invasive procedure can reduce pelvic cancer bulks effectively and selectively.     

Poly-L-Lysine Inhibits Tumor Angiogenesis and Induces Apoptosis in Ehrlich Ascites Carcinoma and in Sarcoma S-180 Tumor

Background: This study focuses on the role of Poly-L-lysine (PLL), an essential amino acid, on molecular changes of tumor angiogenesis suppression, pro-apoptotic and anti-apoptotic gene expression after treatment on Ehrlich ascites carcinoma (EAC) and solid sarcoma-180 tumor cells bearing mice. Materials and Methods: The cell viability was carried out using MTT assay. The antitumor activity was evaluated by treatment with PLL at 20 and 40mg/kg/b.w doses for 14 days in EAC ascites tumor and 21 days for Sarcoma-180 solid tumor model. Several tumor evaluation studies, haematological and biochemical parameters were estimated. Importantly, the tumor cell apoptosis was assessed using microscopic observations, DNA fragmentation assay, Flow cytometric analysis, cell-cycle and electron-microscopic study, following which, the expression of several signal proteins related to pro-apoptosis, anti-apoptosis and tumor angiogenesis were quantified using western blotting and immunohistochemistry study. Results: Precisely, PLL had cytotoxic effect on K562; A549; U937 and B16F10 cancer cells. Significant decreases in liquid and solid tumors and increased life span of treated mice were observed (P<0.05). Typical morphological changes, apoptosis bleb phenomenon and sub-G1 cell cycle arrests revealed that PLL promoted apoptotic cell death. Western blot and immunohistochemistry confirms, PLL activated apoptotic signalling cascades through down regulation of Bcl-2 and CD31 protein and up-regulation of Bax and p53 proteins. The anti-angiogenic effects were also accompanied with decreased VEGF expression and reduced peritoneal-angiogenesis and microvessel density. Conclusions: The antitumor and antitumor-angiogenic activity of PLL was confirmed from all the results via up and down regulation of relevant signal proteins reported in this publication.     

Protective effect of Thuja occidentalis against radiation-induced toxicity in mice

The effect of Thuja occidentalis against damage induced by gamma radiation was studied. Whole-body exposure of Swiss albino mice to gamma-rays (6 Gy) reduced the total white blood cell count to 1900 cells/mm(3) on the third day, which was elevated to 2050 cells/mm(3) by the administration of alcoholic extract ofT occidentalis (5 mg/dose/animal, intraperitoneally). Six animals from each group were killed after 2, 7, and 11 days of irradiation to detect the bone marrow cellularity and radiation-induced toxicity. The number of bone marrow cells and alpha-esterase positive cells in control animals after 11 days was reduced to 12.2 x 10(6) cells/femur and 693.5/4000 cells, respectively. In T occidentalis-treated animals, bone marrow cellularity was increased to 16.9 x 10(6) cells/femur and alpha-esterase positive cells were 940/4000 cells, a nearly normal level. Alcoholic extract of T occidentalis reduced the elevated levels of GPT and alkaline phosphatase in liver and serum after irradiation. The lipid peroxidation levels were also lowered in the irradiated animals treated with the Thuja extract.     

Dose rate effects on the survival of normal hematopoietic stem cells of BALB/c mice

The use of total body irradiation (TBI) to ablate malignant stem cells in leukemia patients prior to bone marrow transplantation and the use of hemibody irradiation (HBI) for treating osseous metastases have focused attention on the dose rate effects, if any, exhibited by normal or malignant hematopoietic stem cells. Using male BALB/c mice 10 to 12 weeks old, we investigated dose rate effects at 103, 45 and 8 rad/min over the dose range from 100 to 500 rad. Bone marrow cells from the femurs of irradiated donor mice were transplanted into lethally irradiated (720 rad) mice of the same age, sex, and strain. Recipient mice were sacrificed 9 days later, their spleens fixed, stained with Bouin's solution, and the macroscopic colonies counted to determine the number of colony forming units (CFU) per femur. Surviving fractions were determined by comparisons to the CFU's of non-treated controls. The logarithms of the surviving fractions, S, versus dose, D, (in rad) were least squares fitted and the extrapolation number, n, and D0 obtained. The extrapolation numbers ranged from 0.65 +/- 0.15 to 0.81 +/- 0.08, and D0 ranged from 61.7 +/- 3.4 to 69.0 +/- 2.8. There are no statistically significant differences between the n's and D0's for these different dose rates over the dose range from 100 to 500 rad, as measured by spleen CFU assay of normal femoral marrow. The D0's are appropriate for this radiosensitive mouse strain. These data are compared to those from other studies using the same method of CFU assay.