Objective To establish chronic stress model of depression in adolescent rats and to examine the effects of different antidepressant treatment on depression and anxiety-related behaviors.Methods Male Wistar rats were given 21-day chronic mild stress (CMS) during their adolescence (postnatal day 30～50, PND30～50).During stress period, rats were treated with fluoxetine (10 mg/kg i.p.) or imipramine (10 mg/kg i.p.), respectively.After stress, rats were tested for behavioral observation using body weight gain, saccharine test, open field and elevated plus-maze (EPM).Results Compared with control/vehicle (n=10) group, stress/vehicle (n=11) group displayed lower weight gain, saccharine preference index and the number of rearing in open field (P<0.05).Antidepressant fluoxetine, but not imipramine reversed anhedonia and the decrease of the number of rearing induced by stress.In addition, compared with early adolescent(PND29) rats, late adolescent (PND52) rats in control/vehicle group exhibited less open arm entries and open arm time, more closed arm time in EPM (P<0.05).Rats in stress/vehicle group showed more open arm entries and less closed arm time than controls(P<0.05).Both fluoxetine and imipramine had no effects on such changes.Conclusions Stress can induce the depression-like behavior in adolescent rats.Fluoxetine, but not imipramine,can effectively reverse anhedonia induced by stress.However, Both antidepressants have no significant effects on stress-induced decrease in developmental increment of anxious behavior during adolescence.These data suggest that chronic mild stress have complicated effects on depressive and anxious behavior in adolescent rats.

Objective To evaluate the possible mechanism of traumatic brain injury (TB1) affecting the speed of bone fracture healing.Method TBI combined with unilateral tibial fracture (group A) was used to build multiple injury model and simple unilateral tibial fracture (group B),and the FOS,JUN,bFGF,and VEGF protein expression in different time points between the two groups were compared,and roentgenogram was used for the evaluation of bone healing.Results The expression of FOS,JUN,bFGF,and VEGF protein of the cerebral tissue was low in the normal rats,but was slightly enhanced in group B.There was consistence of development for FOS and JUN expression in the brain tissue in group A,reaching peak at post-TBI 3 hours,and then reducing to control level after 12 hours.The bFGF and VEGF reached peak at post-TBI 12 hours and 24 hours and reduced to control level after 72 hours,respectively.In group A and group B,an increase in the FOS,JUN protein expression around the fracture site was observed at 3 hours after injury,which reached the peak at 6 hours,and reduced to the control level after 24 hours;the comparison between group A,group B and the control group at 3 hours,6 hours and 12 hours had significant difference (P

Objective To explore the value of dual-phase contrast-enhancement multislice computed tomography (MSCT) in the assessment of acute myocardial infarction volume and perfusion in porcine models. Methods The distal left anterior descending coronary arteries of 5 pigs were balloon-occluded for 90 min and followed by reperfusion. MSCT was performed 1 min (early phase) and 5 min (delayed phase) after administration bolus of 100 mL of iodinated contrast material 30 min after reperfusion. On the same day, hearts were excised, sectioned in 8 mm short-axis slices, and stained with TTC. Infarction volume was defined as the sum of the hyper-enhanced area and surrounding hypo-enhanced area in all slices on delay enhanced phase of MSCT and the TTC-negative area on TTC staining slices. Infarction volume was expressed as percentage of total slice volume. Results Acute infarction detected by MSCT was characterized by early myocardial perfasion defects in the early phase of the contrast bolus (early defects) with surrounding residual defects and late enhancement observed in the late phase. Mean CT attenuation value of early defects was significantly different from CT attenuation value of remote myocardium [(213±55)HU vs (304±30)HU](P < 0.05), CT attenuation values of residual defects and late enhancement were also significantly different from those of remote myocardium [(360±75) HU vs (90±37) HU and (152±23) HU vs (190±37) HU, repectively](P < 0.01, P < 0.05). The mean infarction volume was (8.9± 1.0)% on MSCT and (9.2±1.4)% on TTC pathology images. The infarction volume assessed by MSCT compared well with TTC staining slices. Conclusion Acute reperfused myocardial infarction zone has specific enhancement pattens different to remote normal zone on dual phase MDCT, which is in good agreement with in vivo Trc pathology in the assessment of acute reperfused myocardial infarction shortly offer reperfusion.

BACKGROUNDFeatures of necrotic lesions and various interventions could affect the biomechanics of the femoral head. A three-dimensional finite-element analysis was designed to demonstrate necrotic femoral head stress changes with various sizes of necrotic lesions, and evaluate the effect of tantalum rods on preventing femoral head cracking.

METHODSFemoral computed tomography scans were used to build a normal three-dimensional finite-element femoral head model in a computer. Based on the normal model, necrotic models of different lesion diameters (15 mm, 20 mm and 30 mm) were created, as were the repaired models with tantalum rods for each diameter. After a series of meshing and force loading, the von Mises stress distributions, simulating single-legged stance, and stresses on specific points under loaded conditions were determined for each model.

RESULTSDeep exploration into the burdened area of the femoral head indicated that higher stresses to the femoral head were observed with a larger necrotic lesion; the largest stress concentration, 91.3 MPa, was found on the femoral head with a lesion diameter of 30 mm. By contrast, topical stress on the surface of the necrotic regions was lowered following implantation of a tantalum rod, and the changes in stress were significant in models with lesions of 15 mm and 30 mm in diameter, with the best biomechanical benefit from the tantalum rod found with a lesion diameter of 15 mm.

CONCLUSIONSFemoral heads with larger necrotic lesions usually have a higher stress concentration and a higher risk of collapse. Various sized lesions on the femoral head can benefit from the mechanical support offered by the implantation of a tantalum rod; however, femoral heads with smaller sized lesions may benefit more. A thorough evaluation of the lesion size should be conducted prior to the use of tantalum rod implants in the treatment of femoral head necrosis.

Femur Head ; physiology ; Femur Head Necrosis ; physiopathology ; Finite Element Analysis ; Humans ; Stress, Mechanical

AIMTo immunolocalize the c-mos gene product and to investigate its spatial and temporal expression in mouse testis during postnatal development.

METHODSSemi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization techniques were used to examine c-mos mRNA and indirect immunofluorescence was used to localize c-Mos protein in mouse testis on postnatal days 14, 21, 25, 28, 30, 35, 49 and 70.

RESULTSc-mos mRNA remained low on postnatal days 14-21, increased abruptly from day 25 and peaked on day 30. Its levels decreased a little on day 35 and became almost stable thereafter until day 70. c-mos mRNA was localized in the nucleus and cytoplasm of the spermatocytes and round spermatids. The nuclear staining was much stronger than the cytoplasmic staining. Using a polyclonal anti-c-Mos antibody, Western blotting detected a single band at 43 kDa in testis lysate. c-Mos protein was exclusively localized to the elongating spermatids and was first detected on postnatal day 30. The number of c-Mos-positive spermatids increased progressively till day 49 and stabilized thereafter.

CONCLUSIONThe c-mos gene displays a spatial and temporal expression pattern in the mouse testis during postnatal development at both the mRNA and protein level. This suggests that c-mos might play important roles in spermatogenesis.

Animals ; Fluorescent Antibody Technique, Indirect ; Gene Expression ; Genes, mos ; genetics ; Male ; Mice ; Reverse Transcriptase Polymerase Chain Reaction ; Spermatocytes ; growth & development ; metabolism ; Spermatogenesis ; genetics ; Testis ; metabolism

BACKGROUNDMycoplasma pneumoniae (M. pneumoniae) is one of the common pathogens causing atypical pneumonia. In recent years, resistance to macrolides has become more common, especially in China. Previous studies have confirmed that the mutation at position 2063 in domain V of the 23S rRNA is the most prevalent, followed by the mutation at position 2064. Reported molecular detection methods for the identification of these mutations include direct sequencing, restriction fragment length polymorphism analysis, real-time polymerase chain reaction (PCR) with high-resolution melt analysis, and nested PCR-linked with capillary electrophoresis, etc. The most commonly used method for monitoring resistance-conferring mutations in M. pneumoniae is direct DNA sequencing of PCR or nested PCR products. However, these methods are time-consuming, labor-intensive or need expensive equipments. Therefore the development of rapid and sensitive methods is very important for monitoring the resistance globally.

METHODSIn this study, we reported a fast and cost-effective method for detecting 2063 and/or 2064 macrolide resistant mutations from specimens using a modified allele-specific PCR analysis, and all results were compared with the sequencing data. We also analyzed the clinical courses of these samples to confirm the modified allele-specific PCR results.

RESULTSAmong 97 M. pneumoniae specimens, 88 were found to possess mutations by this method, and all modified allele-specific PCR analysis results were consistent with the sequencing data. The data of the clinical courses of these 97 cases showed that they suffered from severe pneumonia. Erythromycin showed better efficacy on cases from which no macrolide resistance mutation was found on their specimens. However, in some cases from which mutations were detected, erythromycin monotherapy had poor efficacy, and on these patients severe symptoms improved only when azithromycin was added to the treatment.

CONCLUSIONSThe drug-resistant M. pneumoniae is very common in Beijing, China. Our modified allele-specific PCR analysis can identify erythromycin resistant mutations more rapidly from specimens than any other method currently available. Erythromycin is still effective for treating patients infected with the mutation negative M. pneumoniae, but this treatment fails to work on mutant organisms. This method can facilitate clinicians in selecting appropriate therapy within short timescales.

Alleles ; Anti-Bacterial Agents ; pharmacology ; China ; Drug Resistance, Bacterial ; genetics ; Erythromycin ; pharmacology ; Mycoplasma pneumoniae ; drug effects ; genetics ; Polymerase Chain Reaction ; methods

OBJECTIVETo construct a modified and enhanced thymidine kinase (TK) vector regulated by human telomerase catalytic subunit promoter (hTERT) promoter and cytomegalovirus (CMV) enhancer and its killing effect on nasopharyngeal carcinoma in vitro and in vivo and its safety in vivo.

METHODSThe pGL3-basic, as basic vector template, was linked and constructed into TK vector regulated by hTERT promoter and CMV enhancer with mono-promoter vector as control. Enhanced TK expression was confirmed by fluorescent microscopy and real time fluorescent quantitative PCR. Telomerase activity was measured by stretch PCR. Tumour killing effects were examined by MTT and Boyden areola. The effects of enhanced TK on the invasiveness of tumor cell NPC 5-8F and the growth of xenograft implanted in nude mice were investigated.

RESULTSCompared with non-enhanced vector, TK expressed by the enhanced vector significantly increased in NPC 5-8F and MCF-7 cells, telomerase activity was positive in human in NPC 5-8F cells and breast cancer MCF-7 cells and negative in control human blood vessel endothelium ECV-304 cells. After ganciclovir(GCV) treatment, NPC 5-8F cell survival rate and invasiveness decreased and tumor progress of NPC xenograft implanted in nude mice was inhibited, without obvious toxicity effects on mouse liver and kidney.

CONCLUSIONSThe enhanced TK vector regulated by hTERT promoter and CMV enhancer can obviously and specifically inhibit and kill nasopharyngeal carcinoma cells in culture and nasopharyngeal carcinoma xenograft in nude mice in vivo, without obviously toxic side effects on nude mice. The targeted and enhanced TK gene vector with high performance may be a new tumour targeted gene therapy strategy clinically to aim directly at most malignant tumours including nasopharyngeal carcinoma, with more extensive anti-cancer spectrum.

Animals ; Cell Line, Tumor ; Cell Survival ; Cytomegalovirus ; genetics ; Genetic Vectors ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Nasopharyngeal Neoplasms ; therapy ; Promoter Regions, Genetic ; Regulatory Sequences, Nucleic Acid ; Telomerase ; genetics ; Thymidine Kinase ; genetics ; Transfection

BACKGROUNDProgrammed cell death 5 (PDCD5) is a novel apoptotic regulatory gene that promotes apoptosis in various tumor cells. Studies have shown that PDCD5 accelerates the apoptosis of synoviocytes in vitro, implying a potential role in rheumatoid arthritis (RA) pathogenesis. This study examined the expression of PDCD5 in serum and synovial fluid of RA patients, its effect on the expression of inflammatory cytokine, interleukin-17 (IL-17), and the assessment of disease activity in RA.

METHODSPDCD5 and IL-17 levels in serum and synovial fluid from 18 patients with RA and 22 patients with osteoarthritis (OA) were detected using enzyme-linked immunosorbent assay (ELISA). Concentrations of serum PDCD5 in 40 healthy people were also detected as controls. As disease activity indices, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), and X-ray grading scale were also evaluated.

RESULTSSerum and synovial fluid PDCD5 levels in RA patients were significantly higher than those in OA and healthy controls. Serum PDCD5 level was inversely correlated to CRP and ESR, and was significantly higher in the RF negative group than in the positive group. PDCD5 level was also negatively correlated with IL-17 levels both in serum and synovial fluid of RA patients. However, differences in synovial fluid PDCD5 level from RA patients at different Larsen stages were not detectable.

CONCLUSIONSPDCD5 affects RA pathogenesis. Insufficient apoptosis of fibroblast-like synoviocytes and inflammatory cells in RA could increase the expression of PDCD5 protein. As PDCD5 levels correlated negatively with disease activity indices and IL-17 level, PDCD5 could become a target in the diagnosis and treatment of RA.

Aged ; Apoptosis ; Apoptosis Regulatory Proteins ; analysis ; blood ; physiology ; Arthritis, Rheumatoid ; etiology ; Blood Sedimentation ; C-Reactive Protein ; analysis ; Female ; Humans ; Interleukin-17 ; analysis ; blood ; physiology ; Male ; Middle Aged ; Neoplasm Proteins ; analysis ; blood ; physiology ; Synovial Fluid ; chemistry

OBJECTIVETo study whether combined detection of the methylation status of vimentin, sFRP1, and HPP1 gene can increase the positive methylation rate in colorectal cancer.

METHODSTissue samples were collected from 90 patients with colorectal cancer, 60 patients with adenomatous polyp, and 20 healthy controls. DNA was extracted and the methylation status of vimentin, sFRP1, and HPP1 gene was detected by Methylation-specific PCR (MSP). The relationship between clinicopathologic features of colorectal cancer and gene methylation was analyzed.

RESULTSThe methylation rates of vimentin, sFRP1, and HPP1 were 66.7%, 68.9%, and 72.2% in colorectal cancer, 53.3%, 55.0%, and 50.0% in colorectal adenomas, and 0, 0, and 5.0% in healthy controls, respectively. The methylation of each of the three genes in colorectal cancer tissues was higher than colorectal adenomas and healthy controls(P<0.05). The diagnostic sensitivity by combining three methylation markers was 93.3% in colorectal cancer, 76.7% in colorectal adenomas, which was higher than the sensitivity using single gene testing(P<0.05). No significant associations existed between the methylation status of the three genes and clinical characteristics including sex, age, tumor location, lymph node metastases, distant metastasis, and TNM stage(P>0.05).

CONCLUSIONSDNA methylation levels of vimentin, sFRP1 and HPP1 are significantly higher in colorectal cancer tissue. Combined detection significantly improves the positive rate of methylation, and may be used as early diagnosis method for colorectal cancer.

Adult ; Aged ; Aged, 80 and over ; Ataxia Telangiectasia Mutated Proteins ; genetics ; Case-Control Studies ; Colorectal Neoplasms ; diagnosis ; genetics ; DNA Methylation ; Female ; Humans ; Male ; Membrane Proteins ; genetics ; Middle Aged ; Neoplasm Proteins ; genetics ; Promoter Regions, Genetic ; genetics ; Vimentin ; genetics

OBJECTIVETo compare the knee osteoarthritis (OA) models in rabbits by different concentrations of papain and provide data for exploring pathogenesis and treatments of this disease.

METHODSSixty New Zealand white rabbits were randomly divided into four groups of 15 each and given injections into the right knee on days 1, 3 and 5 including intra-articular injections of 2%, 5% or 10% (w/v) papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg (experimental groups). The 0.9% NaCl (w/v) with a dose of 0.1 ml/kg were injected intra-articularly into the right knees of rabbits in the control group. The rabbits were sacrificed at 2, 4, 6 weeks respectively after the initiation of papain injection and these OA models were evaluated through recording the width of knee joint, performing the morphological observation and histological evaluation of articular cartilage and synovium.

RESULTSThe degenerative changes were demonstrated in knee joints of rabbit in all experimental groups, such as thinner articular cartilage, fibrillation and destroyed cartilage matrix, and inflammation, proliferation, and degeneration of the synovial tissue. All these changes were much worse with increased concentration and prolonged observation time.

CONCLUSIONDifferent severity of OA are established through intra-articular injections of 2%, 5% or 10% papain and 0.03 mol/L L-cysteine at the dose of 0.1 ml/kg. These models are of the characters of short period and a good reproducibility.

Animals ; Disease Models, Animal ; Male ; Osteoarthritis, Knee ; chemically induced ; pathology ; Papain ; toxicity ; Rabbits