1.Investigation on the curative effect of brucellar spondyfitis
Xin-ming, YANG ; Wei, SHI ; Ya-kun, DU ; Yan-lin, YIN ; Xian-yong, MENG ; Yu-wei, ZOU
Chinese Journal of Endemiology 2008;27(6):699-703
Objective To investigate the curative effect of brucellar spondylitis,so as to provide scientific proof for improving the curative level of the disease.Methods Epidemiological information was collected from 113 patients diagnosed as brucellar spondylitis,who were divided into 5 groups according to different drugs and drug combinations of doxycycline,gentamicin,sulfamethoxazole and rifampicin.Then the curative effect was investigated.Twenty-one patients who had greater paoas muscle abscess or Para vertebral abscess,intraspinal abscess of spinal canal,necrotic intervertebral disk and major osteolasia received the minimal invasive surgery and the focus removal surgery.Results The occurrence of the disease in female was much higher than that in male.Grazing and breeding beasts was the principal route of infection.Lumbars was mostly involved.they usually was infected in the adjacent 2 piece.L4 was the most common and seriuous one.The curative effect of doxycycline group was better than that without doxycycline(72.60% vs 35.00%,X2=15.14,P<0.05).Doxycyeline+gentamicin+sulfamethoxazole was reeommended as the first choice.However,the curative effect did not increase despi~course of the treatment prolonged.The heMing rate and effective rate after 1 course was 52.21%(59/113)and 92.04%(104/113).that after 2 courses 58.41%(66/113)and 95.58%(108/113),that after 3 courses 59.29%(67/113)and 95.58%(108/113).The healing rate in different course did not present differences(P>0.05).21 patients undergoing surgery were followed-up,12 patients were after 2 years and 9 patients were between 1-2 years.The healing rate was 95.24%(20/21),1 case was healed basically,the effective rate was 100%.None reoccurred.Conclusions There are characterized features in clinical epidemiology of the brucell spondylitis.Long term,adequate in dosage,combination and multi-approach use of antibiotics is the most reliable way to treat and prevent it from recurring.But fof the patients soitable for surgery.the minimal invasive surgery or the focus removal could shorten the course of therapy,decrease the complications and increase the cure rate.
2.Relationship between work locus of control and occupational stress in oil workers.
Xian-Hai MENG ; Ya-Hui HE ; Shan-Fa YU ; Xiu-Ying QI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2008;26(12):718-720
OBJECTIVETo investigate general states of the work locus of control and explore the relationship between work locus of control and occupational stress in oil workers.
METHODS582 oil workers were investigated by using the General Questionnaire and Occupational Stress Measure Inventory.
RESULTSThere were significant differences in WCLS score between two age groups (= 30 years old group and < 30 years old group) (t = 2.093, P = 0.037). Values of interpersonal relationship, person responsibility, promotion, participation, autonomy, task consistency, challenge, job satisfaction, mental health, self-esteem and coping strategies were higher in the group of internal locus of control; values of role ambiguity, working prospect, depression and social support were higher in the group of external locus of control (P < 0.05). Work locus of control had positive relation with role ambiguity, working prospect, depression, and social support, and negative with interpersonal relationship, promotion, participation, task consistency, challenge, job satisfaction, mental health, self-esteem and coping strategies. In the regression analysis, work locus of control was the major predictive factor of work satisfaction.
CONCLUSIONWork locus of control is associated with many occupational stress factors. The group of extrinsic work locus of control experience more stress in oil workers.
Adaptation, Psychological ; Adult ; Female ; Humans ; Internal-External Control ; Male ; Mental Health ; Middle Aged ; Multivariate Analysis ; Occupational Diseases ; psychology ; Petroleum ; Regression Analysis ; Stress, Psychological ; Surveys and Questionnaires
3.Job satisfaction and its influential factors in oil production workers.
Ya-hui HE ; Xian-hai MENG ; Shan-fa YU ; Xiu-ying QI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2008;26(3):161-164
OBJECTIVETo investigate the job satisfaction and its influential factors in oil production workers.
METHODS423 oil production workers were investigated using the Occupational Stress Instrument.
RESULTSThe job satisfaction, job organization satisfaction, job itself satisfaction in the workers aged < 30 years old (45.69 +/- 10.98, 22.63 +/- 6.16, 23.07 +/- 5.39 respectively) were lower than those in workers aged > or = 30 years old (49.34 +/- 10.12, 24.60 +/- 5.40, 24.74 +/- 5.36 respectively) (P < 0.01). The job satisfaction in the groups of different service length was significantly different. The job satisfaction in the workers of service length 5-10 years was the lowest compared with those of service length < 5 years and > 10 years (P < 0.05). The gender, education, marriage did not show obvious influence on the job satisfaction. The relationship between psychological health, work locus of control, coping strategies, affective balance and social support showed a statistical significance difference (P < 0.01). Regression was analyzed by taking job satisfaction as strain and personal characters, occupational stress factors, coping as independent variables. Five variables entered regression equation. They were work locus of control, affective balance, social support, psychological health and coping strategies.
CONCLUSIONThe job satisfaction of oil production workers is affected by multiple factors such as the age, work length and social support.
Adult ; China ; Cross-Sectional Studies ; Extraction and Processing Industry ; Female ; Humans ; Job Satisfaction ; Male ; Middle Aged ; Petroleum ; Surveys and Questionnaires ; Young Adult
4.A new mutation (1062 del 16) of iduronate-2-sulfatase gene from a Chinese patient with Hunter syndrome.
Yi-bin GUO ; Jing-xin PAN ; Ya-xian MENG
Journal of Zhejiang University. Science. B 2007;8(8):566-569
OBJECTIVETo identify the mutations of iduronate-2-sulfatase (IDS) gene, to reveal its mutation features, and to establish a basis for genetic counseling and prenatal gene diagnosis of Hunter syndrome.
METHODSUrine glycosaminoglycans (GAGs) assay, PCR and DNA sequencing were performed to detect mutation of IDS gene of the patient and his parents.
RESULTSThe result showed that the patient was: DS(++), HS(++), KS(-), CS(-), and that both of his parents were negative. A frame-shift deletion mutation (1062 del 16) was identified in exon 7 of the patient's IDS gene. His parents' genotypes were normal.
CONCLUSIONThe patient's mutation was not inherited by his parents but a novel one. The mutation probably altered the primary structure and tertiary structure of IDS enzyme protein remarkably and lowered the activity of IDS enzyme greatly. Therefore it is supposed to be the direct cause of the disorder.
Asian Continental Ancestry Group ; genetics ; Base Sequence ; Child, Preschool ; Female ; Glycoproteins ; genetics ; urine ; Humans ; Male ; Mucopolysaccharidosis II ; enzymology ; genetics ; urine ; Mutation ; genetics
5.Effect of Banxia Qinlian Decoction on Th17/IL-17 Immune Inflammatory Way of Sjögren's Syndrome NOD Model Mice.
Yan LU ; Yi CHEN ; Ya-nan WANG ; Hui LIU ; Ji-sheng ZHANG ; Wei-guo MA ; Zhi-ming SHEN ; Jie WANG ; Kang WANG ; Feng-xian MENG
Chinese Journal of Integrated Traditional and Western Medicine 2015;35(5):612-617
OBJECTIVETo explore the molecular mechanism of exocrine immune inflammatory injury of Sjögren's Syndrome and the intervention of Banxia Qinlian Decoction (BQD).
METHODSTotally 18 female NOD mice were randomly divided into the model group, the positive drug group, and the BQD group, 6 in each group. Six female BALB/c mice were recruited as a blank control group. Mice in the blank control group and the model group were gavaged with deionized water at the daily dose of 0.1 mL/10 g body weight. Tripterygium Tablet was administered by gastrogavage to mice in the positive group at the daily dose of 10 mg/kg. BQD was administered by gastrogavage to mice in the BQD group at the daily dose of 60 g crude drugs/kg. After 12 weeks of medication, mice were sacrificed. Their eyeballs were excised and blood collected. Tissues of bilateral parotids and submandibular glands were kept. mRNA transcriptional levels of IL-17, IL-6, type 3 muscarinic acetylcholine receptors (M3R), aquaporin protein-5 (AQP5) were detected by RT-PCR. Expression levels of M3R and AQP5 protein were detected by Western blot. Protein expression levels of IL-17 and IL-6 were detected by ELISA.
RESULTSCompared with the normal group, mRNA transcriptional levels and protein expression levels of IL-17, IL-6, M3R, and AQP5 were significantly up-regulated in the model group (P < 0.01). Compared with the model group, mRNA transcriptional levels and protein expression levels of IL-17, IL-6, M3R, and AQP5 were significantly down-regulated in the positive drug group and the BQD group with statistical difference (P < 0.01, P < 0.05). Compared with the BQD group, mRNA-transcriptional levels of IL-17, IL-6, and M3R, as well as M3R and AQP5 protein expression levels were significantly down-regulated in the positive drug group (all P < 0.01).
CONCLUSIONThe molecular mechanism of BQD in inhibiting SS exocrine neurotoxic injury might be possibly related to regulating Th17/IL-17 immune inflammatory way.
Animals ; Aquaporin 5 ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Interleukin-17 ; metabolism ; Interleukin-6 ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Inbred NOD ; Sjogren's Syndrome ; drug therapy ; immunology ; Submandibular Gland ; Th17 Cells ; Up-Regulation
6.Effect of compound qingqin liquid on the expression levels of ang II and COX-2 mRNA transcription and protein expression in the renal tissue of uric acid nephropathy rats: an experimental study.
Xue-Zheng SHANG ; Wei-Guo MA ; Yi CHEN ; Yan LU ; Ya-Nan WANG ; Yu-Mei XU ; Ling TAN ; Wen GU ; Zi-Chao LIN ; Feng-Xian MENG
Chinese Journal of Integrated Traditional and Western Medicine 2014;34(7):819-825
OBJECTIVETo investigate the effect of Compound Qingqin Liquid (CQL) on the expression level of angiotensin II (Ang II) and COX-2 mRNA transcription and protein expression in the renal tissue of rats with uric acid nephropathy.
METHODSSD rats were randomly divided into the blank control group, the model group, the positive drug group, the high, moderate, and low dose CQL group according to number randomization principle. The model was established by gastrogavage of adenine, accompanied with yeast feeding. Distilled water was given by gastrogavage to rats in the blank control group and the model group. Allopurinol at the daily dose of 9.33 mg/kg was given by gastrogavage to rats of the positive control group. CQL at the daily dose of 3.77 g/kg, 1.89 g/kg, and 0.09 g/kg was respectively given by gastrogavage to rats in the high, moderate, and low dose CQL groups. All treatment lasted for 6 weeks. Rats were randomly divided at week 4 (3 in the blank control group, and 6 in the rest groups), and the rest rats were killed at week 6. The renal tissue was extracted. The expression level of Ang II and COX-2 mRNA transcription were detected by RT-PCR. The expression level of Ang II was detected by ELISA. The expression level of COX-2 protein was detected by Western blot and immunohistochemical assay.
RESULTSCompared with the blank control group, except the mRNA expression of Ang II at week 4, the mRNA and protein expression of Ang II and COX-2 obviously increased at week 4 and 6 in the model group (P < 0.01, P < 0.05). The COX-2 protein expression at week 4 was obviously lower in the high and moderate dose CQL groups than in the model group and the low dose CQL group (P < 0.05); the average integral of optical density value was obviously lower in the positive control group than in the model group. Except the mRNA expression of Ang II in the high dose CQL group at week 6, the mRNA and protein expression of Ang II obviously decreased in the positive control group and each dose CQL group (P < 0.01, P < 0.05). Of them, the effects were better in the high and moderate dose CQL groups than in the positive control group and the low dose CQL group (P < 0.05, P < 0.01). Besides, the mRNA expression of COX-2, the average integral of optical density value were obviously lower in the positive control group and each dose CQL group than in the model group (P < 0.05). The protein expression of COX-2 was obviously lower in the high and moderate dose CQL groups than in the model group (P < 0.05). Of them, the mRNA expression of COX-2 was better in the moderate dose CQL group than in the positive control group (P < 0.05); the protein expression of COX-2 was better in the high dose CQL group than in the low dose CQL group (P < 0.05).
CONCLUSIONCQL was capable of lowering the expression level of Ang II, COX-2 mRNA transcription and protein expression, thus suppressing the inflammatory pathological injury of the renal tissue.
Angiotensin II ; metabolism ; Animals ; Cyclooxygenase 2 ; genetics ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Kidney ; metabolism ; Kidney Diseases ; drug therapy ; metabolism ; Male ; RNA, Messenger ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Uric Acid
7.Effect of compound qingqin liquid on the expression of toll-like receptor in the renal tissue of rats with urate nephropathy.
Yi CHEN ; Yan LU ; Ya-nan WANG ; Zi-chao LIN ; Wen GU ; Ling TAN ; Wei-guo MA ; Hui LIU ; Chun-yan ZHANG ; Feng-xian MENG
Chinese Journal of Integrated Traditional and Western Medicine 2014;34(6):722-727
OBJECTIVETo investigate the effect of compound qingqin liquid (CQL) on Toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) in rats with urate nephropathy, and to explore its renal protection mechanism.
METHODSTotally 55 SD rats were randomly divided into 5 groups, i.e., the normal control group (n =5), the model group (n =10), the positive drug group (n=10), and the high-, medium-, low-dose CQL groups (n=10) respectively. The urate nephropathy model was induced by intragastrically administering adenine and feeding yeast. Distilled water was intragastrically administered at the daily dose of 10 mL/kg to rats in the normal control group and the model group. Allopurinol was intragastrically administered at the daily dose of 9.33 mg/kg to rats in the positive control group. CQL was intragastrically administered at the daily dose of 3.77, 1.89, 0.94 g/kg to rats in the high-, medium-, and low-dose CQL groups. Rats of each group were executed in batches at the 4th and 6th week respectively. Their kidney tissues were taken out to determine the mRNA transcription level of TLR2 and TLR4 by reverse transcription-polymerase chain reaction (RT-PCR). The protein expression level of TLR2 and TLR4 were determined by Western blot. The protein expression level of TLR4 was also detected by immunohistochemical assay.
RESULTSAt week 4 and 6, the protein expression of TLR2 and TLR4 as well as the mRNA transcription of TLR4 increased in the model group, when compared with the control group (P < 0.05, P < 0.01). Compared with the model group, there was no statistical difference in the transcription level of TLR2 mRNA or TLR4 mRNA among the 3 CQL groups (P > 0.05) at week 4 and 6. Additionally, at week 6, the protein expression of TLR4 and TLR2 could be reduced by CQL (P < 0.05, P < 0.01).
CONCLUSIONCQL might protect kidney tissue against inflammatory injury by inhibiting the protein expression levels of TLR2 and TLR4.
Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Kidney ; drug effects ; metabolism ; Kidney Diseases ; drug therapy ; metabolism ; Male ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 2 ; genetics ; metabolism ; Toll-Like Receptor 4 ; genetics ; metabolism ; Uric Acid
8.Effects of the Survivin shRNA-APC double-gene on the expressions of survivin,Cytc,Smac and Caspase-9 in the colon cancer mitochondrial apoptosis pathway
Xi-Xian YUAN ; Feng-Rong WANG ; Xiao-Lan YUAN ; Shu-Juan ZHANG ; Chao WEN ; Meng-Meng ZHANG ; Ya CAO
Journal of Medical Postgraduates 2018;31(6):595-601
Objective Little is known about the effect of RNAi on mitochondrial apoptotic pathways. This study aims to explore the effects of the Survivin shRNA-APC double-gene on colon cancer mitochondrial apoptosis pathway-related factors survivin,cytochrome C (Cytc),second mitochondria-derived activator of caspases (Smac),and cysteine aspartic acid specific protease 9 (Caspase-9) as well as on the apoptosis of colon cancer transplanted tumor (CCTT) cells. Methods Thirty nude mice were randomly divided into five groups of equal number,Survivin shRNA-APC double-gene,survivin shRNA,APC,empty vector and blank transfection. The CCTT model was established in the nude mice by subcutaneous injection of the colon cancer cell strains stably transfected with the Survivin shRNA-APC double-gene,survivin shRNA,APC,an empty vector and HT-29,respectively,into the mid-posterior part of the left armpit of the nude mice. The rate of tumor growth inhibition was calculated by measuring the volume and weight of the CCTTs in the nude mice. The mRNA and protein expressions of survivin,Cytc,Smac and Caspase-9 in the tumor tissue were detected by real time PCR and immunohistochemistry,respectively,and the apoptosis rate of the CCTT cells was detected by TUNEL. Results The model of CCTT was successfully established in the nude mice. Com-pared with the empty vector and blank transfection groups,the mice in the double-gene,survivin shRNA and APC groups showed sig-nificantly decreased average volume and weight of the tumor tissue (P<0.05) but increased inhibition rate of its volume and weight (P<0.05). In comparison with the survivin shRNA and APC groups,the double-gene group exhibited remarkably decreased average volume and weight of the tumor tissue (P<0.05) but increased inhibition rate of its volume and weight (P<0.05). The mRNA and pro-tein expressions of survivin were significantly lower while those of Cytc,Smac and Caspase-9 markedly higher in the double-gene,sur-vivin shRNA and APC groups than in the empty vector and blank transfection groups (P<0.05),the former even lower (P<0.05) and the latter even higher in the double-gene than in the survivin shRNA and APC groups (P<0.05). The apoptosis rate of the CCTT cells was significantly increased in the double-gene ([56.78±3.04]%),survivin shRNA ([33.61±2.02]%) and APC groups ([30.16± 1.72]%) as compared with the empty vector ([10.05±0.42]%) and blank transfection groups ([9.87±0.30])% (P<0.05),even higher in the double-gene group than in the survivin shRNA and APC groups (P<0.05). Conclusion The Survivin shRNA-APC double-gene may induce apoptosis of colon cancer transplanted tumor cells by down-regulating the expression of the apoptosis inhibitor survivin,upregulating the expressions of Cytc,Smac and Caspase-9,and suppressing the growth of the colon transplanted tumor,with more significant abilities than a single gene in regulating apoptosis-related factors,inducing cell apoptosis and inhibiting the growth of the transplanted tumor.
9.Feasibility and clinical application of design about the hollowed titanium stick supporting the femoral head and preventing it from collapsing.
Xin-ming YANG ; Wei SHI ; Ya-kun DU ; Lei ZHANG ; Xian-yong MENG ; Yao-yi WANG ; Wei-Dong ; Zhen-shun HU
China Journal of Orthopaedics and Traumatology 2011;24(7):564-569
OBJECTIVETo evaluate the feasibility and the clinical practicality of the design about the hollowed titanium stick supporting the femoral head and preventing it from collapsing.
METHODSFrom Jan.2003 to Jun.2007, 36 patients (46 hips) diagnosed as cystis degeneration of the femoral head were treated by surgical operation, including 20 males and 16 females with an average age of 40 years ranging from 18 to 56 years old, and the course of the disease was from 10 to 24 months (16 months on average). According to ARCO staging,there were 24 patients (34 hips) in NFH II, of which 11 hips were II a stage, 13 hips were II b stage and 10 hips were II c stage; there were 6 patients diagnosed as osteofibrous,4 patients as simple bone cyst and 2 patients as chondromyxoid fibroma. Under X-ray the percutaneous narrow core decompression and focus infection elimination were performed and supported the sclerotin under the cartilage with titanium stick. The patients were followed-up at the first, third, sixth, twelfth, twenty-fourth and thirty-sixth month after the operation. The clinical evaluation was done by X-ray and the indexes included stable, unstable and abortive. The data was analyzed by Fisher exact probility and the suviaval rate was analyzed by Kaplan-Meier suviaval curve using statistical soft ware SPSS13.5.
RESULTSThere were no unstable or failure cases on each period from the 1st month to the 12th month after the operation, indicating that the supporting effect of the titanium stick was exact during 12 months after the operation. There were unstable and failure cases from the 12th month to the 24th month after the operation, which were mainly in stage NFH II c but the comparision of the stable rate in this period and 12 months after the operation had no obvious statistical differences (P>0.05) indicating that the supporting effect of the titanium stick was feasible during the stage. One of the unstable cases deteriorated and failed but there were no new unstable cases, both the stable rate and the unstable rate had no change and the failure rate rose on the 36th month after the operation. The compar- ision of the stable rate on each period after the operation had no obvious difference (P=0.197>0.05), which indicated that the supporting effect of the titanium stick was persistent. By the difference of the etiology the three-year survival rate of the relevant NFH II c pathological changes was the lowest-70% and the survival rate of the pathological changes induced by other etiological factors was 90.2%.
CONCLUSIONThe design about the hollowed titanium stick supporting the collapsed femoral head is feasible. Using the hollowed titanium stick to support the femoral head and prevent it from collapsing is pragmatic in the clinical and the effect is positive, however, when it comes to the NFH II c pathological changes, the choice should be made discreetly.
Adolescent ; Adult ; Feasibility Studies ; Female ; Femur Head ; diagnostic imaging ; surgery ; Follow-Up Studies ; Humans ; Internal Fixators ; adverse effects ; Male ; Middle Aged ; Prosthesis Design ; methods ; Titanium ; Tomography, X-Ray Computed ; Young Adult
10.Mechanism of cleft palate in mice induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin.
Ya-Lan PU ; Li-Ling LIU ; Li-Qiang GAN ; Xiao-Meng HE ; Yue-Xian FU
Chinese Journal of Plastic Surgery 2011;27(6):448-453
OBJECTIVETo explore the mechanism of cleft palate in mice induced by 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD).
METHODSOn gestation day 10 (GD 10), 12 pregnant mice were randomly divided into two groups as the treated group and the control group with 6 mice in each group. The mice in the treated group received intragastric administration with 64 microg TCDD/kg, while the mice in the control group received equivalent corn oil. The embryos were examined under stereomicroscope to detect the incidence of cleft palate on GD 18.5. Another 18 pregnant mice were randomly divided into two groups (treated group and control group) on GD 10 with 9 pregnant mice in each group. Then each group was divided into 3 subgroups: GD 13.5, GD 14.5 and GD 15.5, with 3 pregnant mice in each subgroup. The palatal shelves were dissected from the embryos for RNA and DNA extraction on GD 13.5, GD 14.5 and GD 15.5. At last the expression of Smad 2-4 and Smad 7 mRNA was investigated by RT-PCR, and the TGF-beta3 promoter methylamine levels were investigated by methylation specific PCR (MSP).
RESULTSThe cleft palate mice model was established successfully by exposing pregnant C57BL/6J mice to TCDD. Total frequency of clefts was 100% in TCDD group, and the frequency of clefts was 0 in the control group. The relative expression of Smad 2 mRNA was 0.263 +/- 0.088, 0.296 +/- 0.016 and 0.159 +/- 0.027 in TCDD group, 0.180 +/- 0.042, 0.282 +/- 0.029 and 0.165 +/- 0.018 in control group. The relative expression of Smad 3 mRNA was 0.453 +/- 0.153, 0.551 +/- 0.160 and 0.328 +/- 0.049 in TCDD group, 0.375 +/- 0.126, 0.510 +/- 0.145 and 0.259 +/- 0.035 in control group. The relative expression of Smad 4 mRNA was 0.675 +/- 0.174, 0.577 +/- 0.070 and 0.396 +/- 0.066 in TCDD group, 0.557 +/- 0.138, 0.587 +/- 0.080 and 0.441 +/- 0.054 in control group. The relative expression of Smad 7 mRNA was 0.283 +/- 0.050, 0.320 +/- 0.068 and 0.169 +/- 0.045 in TCDD group, 0.207 +/- 0.043, 0.288 +/- 0.051 and 0.155 +/- 0.040 in control group. There was no significant difference between the TCDD treated mice and the control (P > 0.05). The TGF-beta3 promoters were at the un-methylation state both in the TCDD treated and control group.
CONCLUSIONIt suggests that TCDD could induce a stable formation of cleft palate, but it is not through the TGF-beta/Smad signaling nor through the modification of TGF-beta3 promoter methylation.
Animals ; Cleft Palate ; chemically induced ; DNA Methylation ; Female ; Mice ; Mice, Inbred C57BL ; Polychlorinated Dibenzodioxins ; toxicity ; Pregnancy ; Promoter Regions, Genetic ; Signal Transduction ; Smad Proteins ; metabolism ; Teratogens ; toxicity ; Transforming Growth Factor beta3 ; metabolism