ABSTRACT
BACKGROUND:Studies have shown that dibutyl phthalate has certain toxicity to the reproductive system of male animals. OBJECTIVE:To investigate the effects of dibutyl phthalate on secretion of rat ovarian granulose cells. METHODS:Ovarian granulosa cells from 25-day-old female Sprague-Dawley rats were cultured in vitro and exposed to different concentrations of dibutyl phthalate (0, 5, 20, 80μmol/L) for 24 hours. Estradiol and progesterone in ovarian granulosa cells were measured by the method of radio-immunity. Expression of the cytochrome P450aromatase and P450 side chain cleavage enzyme mRNA in granulosa cells were examined by real-time PCR. RESULTS AND CONCLUSION:The levels of estradiol and progesterone in granulosa cells decreased after exposure to dibutyl phthalate. With the increase of the dibutyl phthalate concentration, the expression of P450arom and P450scc mRNA decreased gradual y. Dibutyl phthalate could induce reproductive dysfunction and toxicity to female rats.
ABSTRACT
BACKGROUND:Cone-beam computed tomography has been widely applied in the dentistry due to irreplaceable advantages. Among those advantages, linear measurement is one of the important ones. Further studies are suggest to explore the accuracy and repeatability of linear measurement for the whole skul , as wel as the effect of different resolution and scanning thickness on the linear measurement results. OBJECTIVE:To evaluate the accuracy of linear measurement using cone-beam computed tomography (Newtom VG) on the human skul , with two different voxel sizes. METHODS:In this study, 22 anatomic landmarks in four dry human skul s were marked and 11 linear measurements were obtained. These were considered to be the gold standard (real measurement). The skul s were scanned by cone-beam computed tomography (Newtom VG) at two voxel sizes:0.3 mm and 0.15 mm. Linear measurement was performed in axial and coronal planes. SPSS software version 17 was used for data analysis between radiographic measurement and real measurement. RESULTS AND CONCLUSION:The mean differences of real and radiographic measurements were-0.27 to 0.14 in four different sections, and statistical analysis showed no significant difference between linear measurements and gold standard (P>0.05). There was no significant between two different voxel sizes (P>0.05). Cone-beam computed tomography (Newtom VG) is highly accurate and reproducible in linear measurements in the axial and coronal planes. A cone-beam computed tomography scan with a larger voxel size (0.3 mm) is recommended, resulting in lower radiation dose and faster scan time.
ABSTRACT
Objective:To study the effects of an unique anti-inflammatory herbal preparation Zyflamend(ZF)on 7,12-dimethyl-benz anthracene (DMBA)-induced oral carcinogenesis in golden Syrian hamsters.Methods:10 hamsters were used as the blank controls.106 hamsters were treated topically on the left cheek pouch with 0.5% DMBA solution,3 times per week for 6 weeks. Then the hamsters in positive control group(n =40)were not treated afterwards,in the other 2 groups were treated by topically ap-plication of ZF of original solution(high dose,n =33)and 1 ∶1 dilution(low dose,n =33)respectively.Hamsters were sacrificed at the 24th week and tissue samples of the left cheek pouch were obtained for the examination of tumor incidence,histopathology and BrdU immunohistochemisty.Results:Gross inspection showed that the incidences of the tumor in positive,low dose and high dose groups were 86.7%,53.6%(P <0.01 )and 50.0%(P <0.01 ),histopathological examination showed that the tumor incidences were 86.7%,78.6% and 64.3%,respectively(P <0.05).High dose of ZF significantly decreased the incidence of hyperplasia , dysplasia and cancer(P <0.05);decreased BrdU-labeling index(P <0.05).Conclusion:Zyflamend may inhibit DMBA induced oral carcinogenesis and such prevention may be related to the effect of the suppression of cell proliferation.