Although che mical manage ment progra ms have been in place in several countries for more than 30 years they continue to be chal enged by factors such as data quality and quantity,greater de mand on regulatory staff and re-sources,an evolution in hazard and exposure assess ment methods,and continued debate about manage ment progra ms that are risk-based (hazard and exposure)or hazard-based.Countries developing their own che mical manage ment pro-gra ms often wish to learn fro m the experience of others,and thereby have progra ms that either reduce or eli minate so me of the proble ms associated with existing progra ms.However,often even new progra ms face the sa me or new proble ms that have been associated with managing che micals.In this paper we su mmarize so me of the ele ments of existing pro-gra ms in the United States and Europe,the developing progra m in China,and the chal enges associated with the evolution of hazard,exposure and risk assess ment methods.We conclude by suggesting areas where further research may be use-ful for i mproving che mical manage ment progra ms.

Objective To explore the cultural method of lingual keratinocytes and make preparations for further investigation in using lingual keratinocytes as a new choice of seed cells for the reconstruction of tissue engineered corneal epithelium.Methods Keratinocytes were enzymatically dissociated from lingual tissue specimens using 0.25%disepase and 0.05%trypsin.The biological characteristics of the cells were observed through phase microscope.Meanwhile.1ingual kemtinoeytes were immtmohistochemically labeled with broad spectrum keratin antibody (AE1/AF3).Results The cells revealed the form of "road metal" and could be passed for 3 or 4 generations.Immunohistochemistry indicated that lingual keratinocytes were positive for AE1/AE3 staining.Condusion Lingual kemtinocytes of rabbits can be cultured with KSFM in vitm and magnitude quantity can be attained,laying a favorable foundation for lingual keratinocytes as a new choice of seed cells for corneal epithelium reconstruction with tissue engineering.

Objective To investigate the diagnostic value of serum ferritin in children with systemic onset juvenile idiopathic arthritis (SO-JIA). Methods Fifty-seven patients with fever of unknown origin (rectal temperature>38.5 ℃ ) over two weeks and hospitalized in our general medicine ward longer than one week were enrolled in this study. Patients were recorded the course of fever, elinieal symptoms and signs including rash and swollen joints/arthralgia, laboratory tests including complete blood cell count, C-reactive protein, erythroeyte sedimentation rate, lactate dehydrogenase and the level of serum ferritin. SPSS 10.0 was used for statistical analysis. Results Two of 57 patients could not be diagnosed before discharge. The other 55 patients whose diagnosis was confirmed were divided into four groups. Twenty-five patients were SO-JIA,12 patients had hematologic or oncological diseases, 12 patients had infectious diseases and 6 patients had other rheumatic diseases. The level of serum ferritin was significantly higher (P<0.01) in SO-JIA group than in other groups. Moreover, the levels of serum ferritin in SO-JIA group were all higher than normal and the levels of serum ferritin in 76% of SO-JIA group were more than five-fold elevation. Four cut-off levels of serum ferritin level for the diagnosis of SO-JIA were selected based on clinical practice and ROC curve. When the cut-off levels of serum ferritin were 328.25, 529.50, 731.05 ng/ml and 1121.10 ng/ml, the sensitivity for the diagnosis were 100%, 88%, 72%, and 64% respectively, the specificity were 77%, 87%, 90% and 100%,respectively. Conclusion Serum ferritin is valuable for the diagnosis of SO-JIA and 529.50 ng/ml may be a good cut-off level

Total DNA of B. amyloliquefaciens and S. aureus were isolated and cut partially with Hind Ⅲ Separately, The genes for barnase and for staphylococcal nucl ease were obtained by PCR and cloned into pGEM7Z-f(+), The sequencing show that the n ucleotide (nt) sequence of the barnase is 99.3% homologous with the previously determimed sequence and the deduced animo acid (an)sequence found to correspond precisely to the previously determined sequence; the nucleotide (nt) sequence of the staphylococcal nuclease is 99.1% homologous with the previously determined sequence and the deduced amino acid (an) sequence 99.3% homologous with the previously determinded sequence.These have built basis of making use of special expression or activation of nuclease to produce the male sterility plant by plant gene engineering and to explore new antiviral strategy.

Objective:To observe the effect of TGF-β1 on collagen degradation of rabbit keratocytes.Methods:The activity of collagen degradation of keratocytes with three-dime nsional culture in collagen gel was determined with spectrophotometer.Results:TGF-β inhibited collagen degradation of keratocytes in dose-dependent manner.Conclusion:The present result suggests that TGF-β1 has the inhibitory effect on collagen degradation of keratocytes and may help in the treatment of corneal ulceration.

Objective To explore the efficacy of mycophenolate mofetil-based induction or maintenance therapy for children with lupus nephritis combined with Calcineurin inhibitors (cyclosporine A/tacrolimus) for resistant cases.Methods the clinical data were analyzed for 10 patients treated with multi-target therapy (Glucocorticoid + Mycophenolate mofetile+ Cyclosporine A/Tacrolimus) in Department of Nephrology and Rheumatology from January 2005 to December 2011.Calcineurin inhibitor (Cyclosporine A/Tacrolimus) was added when Mycophenolate mofetil-based induction or maintenance protocol was not satisfactory.The data was analyzed by repeated measures data of ANOVA.Results The SLEDAI score (10.9±3.8 vs 7.9±2.6),24 hours urinary protein quantification [(4.0±2.0) vs (2.2±1.8) g] and ESR [(78±10) vs (54±8) mm/l h] were decreased significantly (P＜0.01),while serum albumin [(29±8) vs (34±8) g/L] and complement C3 level [(0.41±0.20) vs (0.70±0.30) g/L] were increased significantly (P＜0.05).The complete remission rate (CR) was 70％ and the response rate was 90％ in the first 6 month,and the CR was 90％ in the last month.Except 1 case withdrawal,the follow-up period for 9 cases was 24 months.Adverse reactions were rare,1 case had lung in-fection,1 case had hyperglycemia and 1 case had transaminase elevation,which disappeared after mana-gement.Conclusion Mycophenolate mofetil combined with Calcineurin inhibitors (cyclosporine A/tacrolimus) is effective for treating lupus nephritis,the dose of induction or maintenance period is low,and adverse reactions are rare.

Objective To study a rare CT finding of pulsatile tinnitus(FT)caused by sigmoid sinus abnormalities.Methods The imaging data of PT caused by sigmoid sinus abnormalities were analyzed retrospectively in 15 patients(15 female).The median age was 45 years(24 to 63 years).The duration of persistence pulsatile tinnitus was from 0.5 year to 36.0 years(median time,2.0 years).The tinnitus was at left side in 5 patients and right side in 10 patients.Fifteen patients underwent HRCT of the temporal bone.Of them,12 patients underwent cerebral CT angiography and CT venogram(CTA/CTV),and 9 patients underwent cerebral digital subtraction angiography(DSA).Nine patients underwent transmastoid reconstruction surgery of the sigmoid sinus.Of them,the tinnitus was at left side in 2 patients and right side in 7 patients.Paired rank sum test was used to compare the cross-sectional area of the sigmoid sinus of the tinnitus side and normal side.Results On HRCT,focal bony coarse defect is shown in the anterior sigmoid wall in 11 patients and anterolateral sigmoid wall in 4 patients.On CTA/CTV,the sigmoid sinus focally protruded into the adjacent mastoid air cells and formed diverticulum in 10 patients.The pulsatile tinnitus disappeared immediately after transmastoid reconstruction surgery of the sigmoid sinus in all 9 patients.The cross-sectional area of the sigmoid sinus of the tinnitus side was 100.6(41.5-96.2)mm~2,it was 77.0(92.1-122.4)mm~2 in the nonmal side(Z=2.158,P=0.031).Conclusion Focal bony defect of the sigmoid wall with sigmoid sinus diverticula is one of the causes which lead to pulsatile tinnitus,which can be easily identified by imaging examination.

AIM: To study cellular and molecular mechanisms of cardiac development associated genes ex- pression and its function during early stage cardiomyogenesis. METHODS: (1 ) Mouse embryonic stem cells (ESC) line D3 culture. (2) Inductive culals of ESC differentiated into cardiac myocytes in vitro.(3) Identification of ESC -derived cardiac myocytes: RNA isolation; synthesis of specific primer and RT - PCR; Label of RT - PCR products with [? - 32P] dATP as probes, purifyed by sephadex G - 50 columns, determined the yield of DNA. RNA dot hy- bridization. RESULTS: 80% of ESC differentiated into cardiomyocytes by improved conditional medium. Cardiomy- ocytes contraCted in a synchronous manner. The results of RT - PCR and RNA blot showed that cardiac genes were expressed abundantly and specifically during the early cardiomyogenesis. CONCLUSIONS: ESC were able to be dif- ferentiate into cardiomyocytes. Different concentrations and components of RA, DMSO and FCS affected ESC car- diomyogenesis in de. The optimal result obtained was from the conditional medium, a mixturce of 2 nmol/L retinoic acid (RA), 0.6% dimethyl sulfoxide (DMSO) and 20% fend calf serum (FCS).

Objective　To investigate the effects of free radicals (FRs) and amyloid β protein 1-40 (Aβ1-40) on the functions of expressed neurotransmitter receptors (NRs) in Xenopus oocytes. Methods　Total RNA and messenger RNA (mRNA) was prepared from 3-month-old Wistar rat brain tissues with Promega kits and microinjected into maturated Xenopus oocytes (stages Ⅴ-Ⅵ) with 50nl (50ng) for each oocyte. The microinjected oocytes were incubated with modified Bath's solution at 19.0℃±1.0℃ for receptor expression and their currents were recorded with double electrode voltage clamp technique. Superoxide anion free radicals (SAFRs) were produced via a reaction system (HPX/XO) with hypoxanthine (HPX, 0.05mol/L) and xanthine oxidase (XO, 0.1U/L). In order to observe the effects of Aβ and SAFRs on the expressed glutamate receptor, HPX/XO and Aβ1-40 were added to incubation solution at 12h, 24h and 96h before recording. Results　The results showed that the oocytes expressed functional NRs originating from rat brain tissues. These NRs included muscarinic acetylcholine (mACh), glutamate (Glu), dopamine (DA), serotonin (5-HT) and γ-aminobutyric acid (GABA). The current characteristics of expressed receptors were inward currents carried by chloride ion with their equibrilium potentials close to -22mV. The extent of effect on the current of expressed glutamate receptor from rat brain was different among different Aβ concentrations and incubation times. Aβ1-40 at a concentration of 20nmol/L had little effect on the currents of expressed rat brain glutamate receptors up to 24h of incubation period; but the currents of glutamate receptor were significantly decreased (25% off, P<0.01) in the treatment of 60nmol/L Aβ1-40 over 24h. Moreover, when 20nmol/L Aβ1-40 was co-incubated over 12h with SAFRs produced by the reaction system of HPX/XO, it was found that the currents of expressed rat brain glutamate receptors had been changed markedly. When the oocytes were co-treated with 60nmol/L Aβ1-40 and SAFRs over a period of 12h, the currents of glutamate receptor significantly decreased (21% off, P<0.05), and the decreased percentage reached 52% over 24h co-treatment with 60nmol/L Aβ1-40 and SAFRs. In addition, vitamin E had a partial effect against this inhibitory effect. Conclusion　The results suggest that Aβ has a kind of inhibitory effect upon the current of the glutamate receptor, similar to the effects of free radicals. The effects can be antagonized by vitamin E. These imply that Aβ may play a role via inhibiting receptor function in the pathophysiology of Alzheimer's disease.

Objective:To analyze the clinical characteristics of children diagnosed with systemic lupus erythematosus(SLE)complicated with thrombotic microangiopathy(TMA)for early recognition.Methods:We retrospectively reviewed the clinical records of 14 SLE patients with TMA hospitalized at Shanghai Children′s Medical Center, Shanghai Jiaotong University School of Medicine from December 2005 to October 2020.Results:The incidence of TMA was 5.65%(14/248)of the hospitalized patients with SLE and 7.87%(14/178)of the hospitalized patients with lupus nephritis.Four patients were boys while ten patients were girls.One boy was six years old and other 13 patients were from 11 to 18 years old.Their SLEDAI scores ranged from 14 to 31, and all of them were severe activity.Renal biopsy of 11 patients during TMA course all revealed lupus nephritis(type Ⅳ, n=8; type Ⅳ+ Ⅴ, n=3). These 14 SLE children were diagnosed with TMA within 3 days to 2 months after admission.At the beginning of the hospitalization, only six patients had both anemia and thrombocytopenia, while eight patients only had moderate anemia.All of the patients had obvious hypocomplementemia.Especially in the patients with first onset of SLE without treatment, their serum levels of C3 were less than 0.17 g/L and C4 were less than 0.07 g/L.Moreover, glomerular filtration rates of these patients were lower than that in normal range.The follow-up time were 0.2-11.3 years(median time was 2.6 years). After treatment, six patients obtained complete remission, and five patients obtained partial remission.One patient had sudden death during the 4th plasmapheresis, and the other two patients deteriorated. Conclusion:Children with SLE and TMA are mostly in severe disease activity, and renal pathology is type Ⅳ lupus nephritis.The SLE children with anemia should be paid special attention to the level of serum complement whether they have thrombocytopenia or not.If the level of serum complements decrease obviously, glomerular filtration rates should be monitored closely and schistocytes should be searched repeatedly in the blood smears of the peripheral blood to facilitate the early recognition of TMA.