TcdA and B toxins secreted by Clostridium difficile( CD) are two important causes of diseases in organisms. The expression of tcdA and tcdB genes is regulated by a few factors located in the pathogenicity locus ( PaLoc) .Studies have indicated that the tcdC gene is likely to act as a negative regulator of toxin gene expression.So far, it has been debatable whether tcdC gene is regarded as a negative regulator.The mechanism of tcdC gene in pathogenesis remains unclear.In this paper, the structure and function of the tcdC gene are summarized, which will help study the mechanism of tcdC gene and obtain optimal drug targets.

Objective:To investigate the role of scavenger receptor BⅡ(SR-BⅡ) in the oxidized low density lipid(ox-LDL) induced foam cells formation promoted by porphyromonas gingivalis(P.g).Methods:Peritoneal macrophages were stimulated with P.g and ox-LDL,and then foam cells formation were checked.The expression of SR-BⅡ was detected by Western blot and real-time PCR.Next,siRNA targeting SR-BⅡ was used to detect the change of foam cells formation.Results:After being stimulated with P.g and ox-LDL,the foam cells formation was significantly increased.During the process of foam cells formation,P.g infection increased the expression of SR-BⅡ.And the knockdown of SR-BⅡ by siRNA significantly reduced the foam cells formation.Conclusion:P.g infection can increase the expression of SR-BⅡ and the regulation of SR-BⅡ expression can change the foam cells formation.

OBJECTIVETo evaluate the effects of a bleaching gel and a whitening strip on the microleakage of three different glass-ionomer cements.

METHODSForty-five freshly extracted human premolars were used and class V cavity was prepared on the buccal and lingual surfaces. The teeth were randomly assigned to A, B and C groups and restored as follows: Conventional strengthen glass-ionomer cement (Ketac Molar Easymix), compomer (F2000) and compomer (Dyract AP). Teeth were kept in distilled water at 37 degrees C for 7 days. Then the specimens were thermocycled for 500 times. Each group was randomly divided into 3 subgroups which were treated for 21 days with one of the following: Whitening strip (14% hydrogen peroxide), bleaching gel (10% carbamide peroxide), or distilled water (control). After bleaching, the teeth were placed in a solution of basic fuchsin dye for 24 hours, then the teeth were sectioned longitudinally to evaluate the dye penetration. The depth of staining along the tooth restoration interface was recorded with a stereomicroscope.

RESULTSThere were no signicant differences between the two bleaching agents in microleakage of restorations (P>0.05). The two bleaching agents did not significantly affect the microleakage of compomer (P>0.05), whereas the microleakage of glass-ionomer cement in the experimental groups was higher than that in the control group (P<0.05).

CONCLUSIONThere are no significant differences in microleakage of restorations between bleaching gel (10% carbamide peroxide) and whitening strip (14% hydrogen peroxide). The two bleaching agents do not significantly affect the microleakage of compomer but adversely affect the microleakage of strengthen glass-ionomer cement.

Bicuspid ; Bleaching Agents ; Compomers ; Composite Resins ; Dental Leakage ; Dental Restoration, Permanent ; Glass Ionomer Cements ; Humans ; Peroxides ; Urea ; analogs & derivatives

Objective To discuss nursing ways to prevent frontal pressure sores for children after cochlear implantation.Methods A total of 267 cases with sensorineural deafness were selected and divided into the control group (admitted from December 2012 to July 2013,115 cases) and the observation group (admitted from August 2013 to March 2014,152 cases) randomly.Skin preparation was done routinely,general nutritional condition and frontal skin condition were evaluated before operation.The control group used conventional elastic bandage after surgery.The observation group used Allevyn Thin foam dressing to cover the forehead skin before pressure dressing by elastic bandage.The incidence of frontal pressure sores was compared between two groups.Results Two cases occurred frontal pressure sores in the observation group and 31 cases in the control group,x2=39.736,P ＜ 0.01.Patients in the control group with pressure sore focused within 1-2 years old,totally 18 cases.Conclusions Nurses should attach great importance to younger children with cochlear implantation to prevent pressure sores.Nursing staff should keep update knowledge of prevention and treatment of pres-sure ulcers,accurately assess skin conditions and risk factors in patients and adopt precautions predictably.

Objectives To investigate the correlation between the level of peripheral blood inflammatory cytokines and kainic acid-induced seizure severity in rats.Methods 140 rats were divided into control and model group randomly,70 rats in each group.Model group rats were injected with kainic acid (10 mg/kg) by intraperitoneal,and the control rats were injected with sodium chloride.The change of their behaviors was observed and the concentrations of TNF-α,IL-1β,IL-4 and IL-10 were determined by ELISA in each group at different times.Results The rats showed epilepsy grand mal in 3 h-9 h after KA injection.The concentrations of TNF-α and IL-1β in model groups were significantly higher than those in control group in 6 h-12 h (6 h:(21.5±3.2) pg/ml vs (12.3±3.1)pg/ml;12 h:(20.6±4.2)pg/ml vs (11.5±3.8)pg/ml)(P＜0.05) and IL-4 in model group was higher at only 12 h ((53.55±3.08) pg/ml vs (33.26±4.16)pg/ml) (P＜0.05).The level of IL-10 in model groups was not statistically significant compared with control group (P＞0.05).Conclusion The proinflammatory cytokines (TNF-α and IL-l β) participate in the seizure procedure,meanwhile their levels and seizure severity have eminent correlations,but antiinflammatory cytokines (IL-4 and IL-10) had not.

Objective To evaluate the efficacy of alendronate sodium combined with dietary and exercise intervention in postmenopausal osteoporosis. Methods 88 postmenopausal osteoporosis patients were enrolled and treated with alendronate sodium and Vitamin D combined with dietary and exercise intervention for 12 months. Bone mineral density (BMD) of lumber spine and femur neck were measured before and after the treatment. Results Medication combined with dietary and exercise intervention significantly increased bone mineral density of postmenopausal osteoporosis patients, and the serum levels of bone alkaline phosphatase (BLAP), alkaline phosphatase (AKP) and tartrate resistant acid phosphatase (TRACP) were significantly higher than those pre-treatment, with significant differences (P<0.05). Conclusion Compared to simple medication treatment, medication combined with dietary and exercise intervention is more effective to enhance medication efficacy and BMD level.

Objective To construct prokaryotic expression vectors for glutamate dehydrogenase(GDH)of Clostridium difficile(CD),and express recombinant GDH in Escherichia coli,and identify its antigenicityed.Methods The entire gene of GDH was cloned from ATCC43255 genome DNA.The recombinant antigens were expressed in E.coli with IPTG induction and purified by Ni-NATBeads.The antigenicity was detected using CD Qick Chek Complete dual-antigen EIA. Results Prokaryotic expression vectors of CD GDH were constructed successfully.The antigen could be identified by specific anti-GDH antibodies.Conclusion The GDH antigen can be used to prepare corresponding antibodies,which facilitate the development of immunoassay for CD GDH.

OBJECTIVETo investigate the constituents of the Annona squamosa and evaluate their anti-tumor activity.

METHODThe compounds were isolated and purified by various column chromatography. Their structures were elucidated by spectral data analysis. Their anti-tumor activity was assayed by SRB method.

RESULTEleven compounds were obtained from the 95% EtOH extract. The structures were determined as: annosquamosin C(1),15, 16-epoxy-17-hydroxy-ent-kau-ran-19-oic acid (2),16,17-dihydroxy-ent-kau-ran-19-oic acid(3), annosquamosin A(4), ent-kaur-16-en-19-oic acid (5), 19-nor-ent-kauran4-ol-17-oic acid (6),16-hydroxy ent-kau ran-19-oic acid (7), ent-15beta-hydroxy-kaur-16-en-19-oic acid (8), annosquamosin B (9), ent-16beta, 17-dihydroxykauran-19-al (10), 16, 17-dihydroxy-ent-kauran-19-oic acid me thyl ester (11). Compounds 1,2,3,5,9 showed different inhibitory activities against 95-D lung cancer cells,the effect of compound 5 was strongest with the IC50 value 7.78 micromol x L(-1); Compounds 2, 5, 9 showed inhibitory activities against A2780 ovarian cancer cells, the effects of compounds 2 and 9 were strong with the IC50 values being 0.89, 3.10 micromol x L(-1), respectively.

CONCLUSIONCompound 2 was firstly isolated from this family, while compound 8 and 10 were first found from this genus and the title species, respectively. The in vitro anti-tumor test showed compound 5 significantly inhibited 95-D lung cancer cells and compounds 2 and 9 exhibited remarkbale activity against A2780 ovarian cancer cells.

Annona ; chemistry ; Antineoplastic Agents, Phytogenic ; analysis ; pharmacology ; Cell Line, Tumor ; Humans ; Plant Bark ; chemistry

Objective:To investigate the expression and significance of endoplasmic reticulum stress apoptosis pathway related proteins in renal cortex of rats with chronic fluorosis.Methods:Twenty four healthy SD rats were divided into 4 groups (6 rats/group, half male and half female) according to their body mass (100 - 120 g) by random number table method, rats in control group drank tap water (fluoride content < 0.5 mg/L), and in low, medium and high fluoride groups drank tap water with fluoride content (sodium fluoride) of 10, 50 and 100 mg/L, respectively. After 180 days of feeding, dental fluorosis was examined, 24-hour urine sample was collected and the content of fluoride in urine was detected by fluoride ion selective electrode method. Renal tissue was taken after anesthesia, and the pathological changes of renal cortex were observed by hematoxylin-eosin (HE) staining. The expressions of endoplasmic reticulum stress apoptosis pathway related proteins [inositol-requiring enzyme 1α (IRE1α), apoptosis signal-regulating kinase 1 (ASK1), C-Jun N-terminal kinase (JNK) and phosphorylated JNK (P-JNK)] were determined by immunohistochemical staining in rat renal cortex.Results:No dental fluorosis was found in control group. The incidence of dental fluorosis in low, medium and high fluoride groups were 2/6, 5/6 and 6/6, respectively. Compared with control group [(5.707 ± 1.190) mg/L], the urinary fluoride in low, medium and high fluoride groups [(17.028 ± 3.006), (34.378 ± 12.045), (94.759 ± 31.773) mg/L] was significantly higher ( P < 0.05), and the urinary fluoride in high fluoride group was higher than that in low and medium fluoride groups ( P < 0.05). HE staining showed that, compared with control group, the cell volume of renal tubules and glomeruli in medium and high fluoride groups increased, the cells arranged closely, and the eosinophilia of the cytoplasm increased. The immunohistochemical staining results showed that there was no significant difference in the expression of JNK protein in rat renal cortex between control group and low, medium and high fluoride groups ( F = 0.07, P > 0.05). The expressions of IRE1α, ASK1 and P-JNK proteins in rat renal cortex in high fluoride group were higher than those of control, low and medium fluoride groups ( P < 0.05), and the expressions of IRE1α and ASK1 proteins in medium fluoride group were significantly higher than those in control and low fluoride groups ( P < 0.05). Conclusion:Long-term excessive fluoride intake can lead to renal cortex injury in rats, and the mechanism of injury may be related to the activation of IRE1α-ASK1-JNK endoplasmic reticulum stress apoptosis pathway.

Objective To establish a rapid method for the detection of SMCY antigen. Methods To Use the technology of colloidal gold immunochromatography with double antibody sandwich assay, the gold labeled pad was coated with colloidal gold labeled SMCY rabbit polyclonal antibody, colloidal gold strip was made for detection of serum, which include 12 serum samples of pig, cattle, dog, chicken and mice and 50 serum samples of human. Results The colloidal gold test strips showed obvious specificity in human and common animal sera and could distinguish between male and female sera. Conclusion This method can be used to identify the serum of women and men, and has certain species specificity, which provides a direction for forensic science to rapidly identify gender of human samples.