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C Shenberg

Publications and source records attributed to C Shenberg.

11 recordsLinked to original sources
PubMed1998

Comparison between levels of trace elements in normal and cancer inoculated mice by XRF and PIXE.

Determination of Rb, Br, Se, Zn, Cu, Fe, and Br/Rb ratio in tissues of mice inoculated with colon and melanoma cancer cells is described. A group of 19 Balb/c mice inoculated with C26 colon carcinoma, 4 C57B1/6 mice inoculated with B16 melanoma, and 13 control mice of both kinds were under investigation. The study was conducted on samples of blood, liver, kidneys, colon, and skin, and the trace element levels in normal and inoculated mice were compared. The inoculation was by subcutaneous injection either at the back or intrafootpad. The blood samples were taken 1, 2, and 3 wk after inoculation, and after 4 wk all the animals were sacrificed. Two nondestructive, complementary analytical methods were used: a modified X-ray fluorescence (XRF) for solid tissue and particle-induced X-ray emission (PIXE) for blood samples. The detection limit (DL) in the PIXE method was 0.35 microg/g dry wt in 600 s counting time and in XRF, 1 microg/g dry sample for Rb, Br, Se and Zn and 2 microg/g for Cu and Fe in 200 s counting time. In all the cases studied, cancerous tissue developed at the site of the injection, and a significant difference in the trace element levels was observed between tissue samples obtained from normal and inoculated mice. The most pronounced effect was an increase in Rb level in the tumor by a factor ranging between 4 and 10 relative to normal tissue, with a corresponding decrease in the Br/Rb ratio (p < 0.05). Smaller changes were found in the Br, Se, Zn, and K levels. The changes in trace element levels in the inner organs were much smaller and seem to be influenced by the site of injection.

Animals↗
PubMed1995

Br, Rb, Zn, Fe, Se and K in blood of colorectal patients by INAA and PIXE.

A preliminary study was conducted on blood samples and blood fractions of 11 colorectal patients and 10 healthy subjects (controls) in Belgium, in order to determine the concentration of some vital trace elements. Two non destructive analytical methods were used for the determination: INAA and PIXE. The agreement between PIXE and INAA was within about +/- 10% for plasma, but for Rb, Se and Fe in whole blood and red cells a difference of +/- 20% was noted; part of the discrepancy may be due to self absorption problems in PIXE, and for Rb, spectral interferences also may have contributed. The precision of the INAA method for the elements studied was found to be +/- 3% for whole blood and red cells and +/- 5% for plasma; the accuracy for Br, Rb and Zn was better than +/- 10% and +/- 17% for Se. The ratios of the concentrations in whole blood to red cells and whole blood to plasma were not significantly different for normals and cancer cases and, therefore, in future studies analysis of whole blood only may be sufficient. The mean values for Br, Rb, Br/Rb ratio, K, Fe and Se were significantly lower for cancer cases than for healthy individuals, and this might be applicable as an additional parameter for differentiating normals from malignant cases.

Aged↗
PubMed1994

The distribution of BrK alpha/RbK alpha peak intensity ratio in human whole blood samples. Comparison between normal and colorectal cancer cases.

A preliminary study was conducted to compare the BrK alpha/RbK alpha peak intensity ratio in colorectal cancer (CRC) patients and healthy subjects (controls) in Israel. Blood samples were obtained from 61 CRC patients and 124 controls. The controls represent a normal population from different areas in Israel. Three hundred microliters of wet whole blood samples were analyzed by the EDXRF method. A weighted mean of 2.45 +/- 0.38 Br/Rb ratio was obtained for CRC patients, as compared with 3.28 +/- 0.40 Br/Rb ratio for controls. The mean value for controls represents only 112 subjects, since 12 individuals of the control group suffered from some other diseases and therefore were not included for the mean value calculation in this group. The results indicate that the Br/Rb ratio in CRC patients is significantly lower (p < 0.05) than in controls. No significant difference was found in Br/Rb ratio correlated to age and sex. It was not possible to draw final conclusion concerning the relationship between the Br/Rb ratio and the malignancy stage, since there was a relatively small number of cases in each stage under investigation.

Adult↗
PubMed1994

An XRF study of trace elements accumulation in kidneys of tumor-bearing mice after treatment with cis-DDP with and without selenite and selenocistamine.

The effect of cis-DDP treatment with and without selenite and selenocistamine was studied on kidneys of tumor-bearing mice. The amounts of cis-DDP, selenite, and selenocistamine injected were chosen so as to be compatible with the treatment of humans. The animals were sacrificed at 7, 14, and 28 d after treatment. The kidneys were removed and subjected to trace element analysis by a novel X-ray fluorescence (XRF) method and for pathological assessment. The results show that following treatment with cis-DDP, K, Fe, Cu, and Zn reach a maximum level after 7 d; K, Fe, and Cu levels were significantly reduced by the addition of selenite. The level of Zn was reduced only in groups treated with selenite whereas that of K and Cu was reduced also in groups treated with selenocistamine with and without cis-DDP. The greatest increase in Pt and Se levels was reached 1 wk after injection with cis-DDP, with and without selenocompounds, and in the case of Pt was partly reduced by addition of selenite. Se returned to control values 2 wk after injection, although Pt was still high in all groups 2 and 4 wk after injection. The results corroborate the findings of our previous studies. The effect of selenocistamine in cis-DDP treated mice was partly insufficient. The pathological examination of the kidneys did not show any differences in the effect of various additives during the study.

Animals↗
PubMed1994

Br/Rb ratio obtained by XRF analysis of kidneys of normal and tumor-bearing mice treated with cis-DDP.

The Br/Rb ratio in kidneys of normal and tumor-bearing mice was studied and a significant difference was found between the two groups. The mice were treated with cis-DDP with and without selenite, with selenite alone, and compared with controls. The animals were sacrificed 7d, 14d, and 21-28d after treatment. The kidneys were removed and subjected to Br and Rb determination by a novel X-ray fluorescence (XRF) method. The results are presented in terms of estimated net count rates under the BrK alpha and RbK alpha peaks. No significant differences were found in Br and Rb levels or in the Br/Rb ratio in kidneys of treated and untreated mice belonging to the same group-normals or lung carcinoma inoculated. However, there was a significant difference in the Br/Rb ratio between the two tested groups (normals and inoculated). Preliminary results on the Br/Rb ratio obtained from normal and malignant tissues of colorectal cancer (CRC) patients and from mice inoculated with melanoma, show the same trend as those from the group of mice with lung carcinoma. In all three groups tested the Br/Rb ratio was 2-4 times higher in normal than in malignant tissue.

Animals↗
PubMed1989

Effect of selenite on the toxicity of cis-DDP in mice: estimation of trace elements.

A significant accumulation of copper, zinc, iron, rubidium and bromine, in addition to platinum, was observed in kidneys and liver of mice treated with cis-DDP. This observation suggests that the toxicity of cis-DDP is due to the overall accumulation of trace elements and not only to the expected high platinum levels. Sodium selenite administration prior to cis-DDP results in fast clearance of all these trace elements from kidneys and liver; control levels are reached within 6 days. This may explain the important reduction in cis-DDP toxicity following selenite administration. An X-ray fluorescence (XRF) facility was used for the evaluation of the trace elements.

Animals↗
PubMed1988

Rapid and simple determination of selenium and other trace elements in very small blood samples by XRF.

Selenium and other trace elements (Cu, Zn, Br, and Rb) were determined in very small (0.75 microL) human serum and mice whole blood samples, by an XRF method. Accurate results of elemental concentration were obtained without the need of exact volume measurement, because of the backscatter correction used. The XRF method is highly sensitive (M.D.L. = 0.06, 0.13, 0.09, 0.07, and 0.05 ppm for Se, Cu, Zn, Br, and Rb, respectively), rapid (counting time--100 s/sample), easy to perform and therefore suitable for routine trace element analyses. The results obtained are in good agreement with the values reported in the literature.

Adult↗
PubMed1984

Factors affecting the labeling of human fibrinogen with 99mTc in vitro.

The preparation of [99mTc]fibrinogen is described. The following factors which could affect the quality of this preparation were studied: pH, SnCl2 and protein concentrations, pre- and post-labeling incubation times and labeling temperature. A 90% labeling yield was achieved by incubating fibrinogen with SnCl2 at pH 9.8 for 22 h before adding the TcO-4 solution. The product obtained was stable and was 85% clottable. The x-ray fluorescence technique was employed to measure the amount of bound tin at different times.

Fibrinogen↗
PubMedDate not supplied

The distribution of selenium in human blood samples of Israeli population--comparison between normal and breast cancer cases.

A preliminary study was carried out in order to compare the selenium concentration in breast cancer patients and healthy subjects (controls) in Israel. Blood serum samples were obtained from 32 breast cancer patients and 36 controls and were analyzed for selenium by the XRF method. A weighted mean of 0.076 +/- 0.014 ppm Se in the blood serum of breast cancer patients, as compared to 0.119 +/- 0.023 ppm Se for controls, was obtained. These results indicate that the concentration of selenium in breast cancer patients is significantly lower than in controls. The relationship between selenium concentration and malignancy stage shows an inverse dependence, i.e., the concentration decreases with stage number.

Adult↗
PubMedDate not supplied

Determination of bromine in blood serum by 125I excited x-ray fluorescence.

A radioisotope excited XRF method based on the use of five 10-mCi 125I point sources arranged in a newly designed configuration is applied to the bromine determination in very small blood serum samples (less than or equal to 50 microL). The possibility of determination of 0.05 micrograms Br in blood serum during 100 s counting time with a standard deviation of +/- 10% is described. The simplicity and low cost of the present method are major advantages over the other nondestructive methods and render it suitable for medical laboratories.

Bromine↗