[Photosensitivity and radiosensitivity of indocyanine green on human cell lines MCF7 and DFW]

In this study with the aim of benefiting from non-laser sources in photodynamic therapy, photo and radio sensitivity of indocyanine green as a sensitizer in photodynamic and radiation therapies were investigated. Based on the broad absorption peak of indocyanine green and using non-coherent light, the experiments were performed on human cells derived from breast cancer and melanoma. To investigate chemical, optical and radiational cytotoxicity and also photosensitivity and radiosensitivity of indocyanine green, different dozes of this material were examined. After 24 h of incubation of cells with indocyanine green, independent treatment groups were exposed to 730 +/- 20 nm light with power densities of 30, 60, and 108 J/cm[2] and 100 kVp x-ray [2 and 4 Gy]. The effect of therapy on cells was determined by MTT test. Indocyanine green showed no significant cytotoxicity. It had a good efficiency for photodynamic therapy using non-coherent sources in the wavelength of 730 +/- 20 nm, and the efficiency of treatment was dependent on the dosage of light. No significant relation between indocyanine green and radiation was observed. According to the findings, indocyanine green can be used as a photosensitizer in the range of 730 +/- 20 nm. Since there was no significant difference between groups which received both radiation and drug and those which received only radiation, indocyanine green cannot be considered as a radiosensitizer

[Assessment of noise level and frequency analysis of equipments used in dental clinics at Mashhad School of Dentistry]

Instruments and equipments used in dentistry field produce sounds with wide spectrum, so dentists and other personnel are exposed to these sounds continuously. The purpose of this study was measuring the received noise level of personnel working in clinics of Mashhad dental school and frequency analysis of sounds at 20-20000 Hz frequency range. In this study, the noise level in operational dentistry, endodontics, prosthodontics, oral surgery, periodontics, pediatric dentistry and orthodontics of Mashhad dental school were assessed in 2004. Sound level measuring device and their establishment and set up were selected in which according to acquired data, the received noise level of dentist and average received noise level of personnel could be calculated. Equivalent noise level [L[Aeq]] measured surrounding central unit of each clinic, was less than 73.2 dB and noise level inside each clinic was less than 69.9dB. The dentists received noise level during work and presence at the studied clinics was measured to be 67.2-83.7 dB. The equivalent maximum noise level in all clinics was related to frequency band of 630 Hz and sounds of operational dentistry, endodontics and periodontics clinics had strong components in high frequency. According to permitted exposure noise level, the received noise level of dentists and personnel in studied clinics were not hazardous, but because of high frequency sounds, it is suggested to repeat the study with systems which can assess analysis of higher frequencies

[Establishment and behavioral study of a tumor model in Balb/c mice for experimental cancer studies]

The establishment of a standard and well-studied animal tumor model in order to evaluate the effects of new anti-cancer therapeutics and the study of tumor biology is crucial to cancer research institutes in Iran. In this study, we established a standard tumor model in Balb/c mice. After the evaluation of the available cell lines, WEHI-164 cells were used for tumor induction in male and female four-week inbred Balb/c mice. On the day 0, mice were inoculated with 7 x l0-6 WEHI-164 cells subcutaneously and tumor dimensions were measured daily. Statistical analysis of the results indicated that there is no significant difference between male and female groups and the yield of 82% about tumor induction was determined. From the day 8, tumor regression was observed