Establishment and validation of improved six-year-old pediatric thorax human model / 医用生物力学

Objective To improve the biological fidelity of the thorax flexible body in the original MADYMO child human model, so as to further study pediatric thorax injuries of child occupant. Methods A finite element model of the six-year-old pediatric thorax was built by adopting the method of reverse modeling based on CT images. By replacing the thorax model with flexible body in MADYMO six-year-old human model, an improved human model containing biomechanical thorax model was developed. The model was verified by joint validation of two tests, including Kroell’s adult chest impact experiment combined with Irwin and Mertz’s scaling method, and Jun Ouyang’s thoracic impact test on pediatric cadavers. Results The response of this established thorax model was in good agreement with scaling method and cadaver test data, and the thorax model was much more accurate than the original flexible body model. The resilience of simulation model was consistent with cadaver test. Conclusions The validity of the model is verified, and can be further used in occupant injury analysis in vehicle frontal crash.

Establishment and validation of improved six-year-old pediatric thorax human model / 医用生物力学

Objective To improve the biological fidelity of the thorax flexible body in the original MADYMO child human model,so as to further study pediatric thorax injuries of child occupant.Methods The finite element model of six-year-old pediatric thorax was built by the method of reverse modeling based on CT images.By replacing the thorax model with flexible body in MADYMO six-year-old human model,an improved human model containing biomechanical thorax model was developed.The model was verified by joint validation of two tests,including Irwin and Mertz's method of scaling channel reported in Kroell's adult chest impact experiment and Ouyang's thoracic impact test on pediatric cadavers.Results The response of this established thorax model was in good agreement with scaling channel method and cadaver test data,and the thorax model was much more accurate than the original flexible body model.The resilience of simulation model was consistent with cadaver test.Conclusions The validity of the model is verified,and the results can be further used for occupant injury analysis in vehicle frontal crash.

Establishment and validation of improved six-year-old pediatric thorax human model / 医用生物力学

Objective To improve the biological fidelity of the thorax flexible body in the original MADYMO child human model,so as to further study pediatric thorax injuries of child occupant.Methods The finite element model of six-year-old pediatric thorax was built by the method of reverse modeling based on CT images.By replacing the thorax model with flexible body in MADYMO six-year-old human model,an improved human model containing biomechanical thorax model was developed.The model was verified by joint validation of two tests,including Irwin and Mertz's method of scaling channel reported in Kroell's adult chest impact experiment and Ouyang's thoracic impact test on pediatric cadavers.Results The response of this established thorax model was in good agreement with scaling channel method and cadaver test data,and the thorax model was much more accurate than the original flexible body model.The resilience of simulation model was consistent with cadaver test.Conclusions The validity of the model is verified,and the results can be further used for occupant injury analysis in vehicle frontal crash.

Pathogens of prostatitis and their drug resistance: an epidemiological survey / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the epidemiological features of the pathogens responsible for prostatitis in the Changshu area, and offer some evidence for the clinical treatment of prostatitis.</p><p><b>METHODS</b>This study included 2 306 cases of prostatitis that were all clinically confirmed and subjected to pathogenic examinations in 3 hospitals of Changshu area from 2008 to 2012. Neisseria gonorrhoeae, mycoplasma urealyticum and chlamydia trachomatis were detected by nucleic acid amplification ABI 7500, the bacterial data analyzed by VITEK-2 Compact, the drug-resistance to antibacterial agents determined using the WHONET 5.6 software, and the enumeration data processed by chi-square test and curvilinear regression analysis using SPSS 19.0.</p><p><b>RESULTS</b>The main pathogens responsible for prostatitis were found to be Staphylococcus haemolyticus (30%), Staphylococcus epidermidis (12%), Enterococcus faecalis (9%), Escherichia coli (6%), Staphylococcus warneri and Staphylococcus aureus (3%), Mycoplasma urealyticum (8%), chlamydia trachomatis (5%) and Neisseria gonorrhoeae (6%). Statistically significant increases were observed in the detection rates of Escherichia coli (chi2 = 17.56, P<0.05), Mycoplasma urealyticum (chi2 = 8.73, P<0.05), Chlamydia trachomatis (chi2 = 8.73, P<0.05) and Enterococcus (chi2 = 8.22, P<0.05), but not in other pathogens. The resistance rates of Gram-positive bacteria to erythromycin and benzylpenicillin G were both above 45%, but with no significant difference between the two, those of Oxacillin (chi2 = 10.06, P<0.05) and Cefoxitin (chi2 = 9.89, P<0.05) were markedly increased, but those of quinolones, gentamycin and clindamycin remained low, except rifampicin (chi2 = 11.09, P<0.05). The resistance rates of Gram-negative bacteria to cefazolin and ampicillin were relatively high (mean 57.3%), and those to ceftriaxone (chi2 = 11.26, P<0.05) and trimethoprim sulfamethoxazole (chi2 =11.00, P< 0.05) significantly high; those to amikacin, cefepime, piperacillin/tazobactam and imipenem remained at low levels with no significant changes. However, the resistance rates of mycoplasma urealyticum to ciprofloxacin (chi2 = 11.18, P<0.05) and azithromycin (chi2 = 9.89, P<0.05) were remarkably increased.</p><p><b>CONCLUSION</b>Gram-positive bacteria are the major pathogens responsible for prostatitis, but Escherichia coli, enterococcus and sexually transmitted disease pathogens are found to be involved in recent years. Quinolones and aminoglycosides are generally accepted as the main agents for the treatment of Gram-positive bacterial infection. However, rational medication for prostatitis should be based on the results of pathogen isolation and drug sensitivity tests in a specific area.</p>

Pharmacokinetics of PEG-rhG-CSF and rHSA-hG-CSF in mice determined with ELISA / 药学学报

Double antibody sandwich-type ELISA was used to detect rhG-CSF in serum to study the pharmacokinetics of rhG-CSF, PEG-rhG-CSF and rHSA-hG-CSF in mice and to confirm that PEGlyation and albumin fusion of rhG-CSF technology can prolong half-life of G-CSF. Pharmacokinetic parameters were calculated with 3P87 software. T1/2 s of rhG-CSF, PEG-rhG-CSF and rHSA-hG-CSF are 2. 1 , 14.2 and 10. 6 h, respectively. T1/2 s of PEG- rhG-CSF and rHSA-hG-CSF are 7, 5 times than T1/2 s of rhG-CSF, respectively. Tpeak s of PEG-rhG-CSF and rHSA-hG-CSF are 15, 13 times than Tpeak of rhG-CSF, respectively. The result of ELISA indicates that PEGlyation and albumin fusion of rhG-CSF technology can prolong half-life of G-CSF.

Characterization of a novel transplantable orthotopic nude mouse model with xenografted human bladder transitional cell tumor (BIU-87) / 中华肿瘤杂志

<p><b>OBJECTIVE</b>A mouse model of orthotopic bladder cancer simulating its human counterpart is of great importance in preclinical evaluation of new treatment modalities such as immunotxin therapy. The aim of the present study is to establish a novel nude mouse model with xenografted human bladder cancer.</p><p><b>METHODS</b>Single cell suspension of an established human bladder transitional cell carcinoma (TCC) cell line BIU-87 was instilled into nude mouse bladders which were pretreated with mild acid washing. The tumor growth in mouse bladder was assessed weekly by magnetic resonance imaging (MRI). At intervals following implantation and MRI tumor detection, the animals were sacrificed for necropsy, histological examination and immunocytochemical studies.</p><p><b>RESULTS</b>The overall tumor establishment was 92.9% (52/56 mice) at 7 - 36 days, while in the subgroup of animals sacrificed at 12 - 13 days, 40 out of 42 animals (95.2%) developed TCC, the majority of which was superficial. The tumor stages were assessed by gross and histopathology. Histological examination confirmed the presence of grade II - III TCC. Immunocytochemistry confirmed that the tumor model maintained the biological and immunological features of BIU-87 cells. The changes seen on MRI images well correlated with the extent of tumor invasion identified by histology. Carcinoma in situ could be detected histologically at 7 - 9 days post-inoculation and progressed into papillary or invasive tumors thereafter.</p><p><b>CONCLUSION</b>The orthotopic BIU-87 TCC model in nude mice is highly reproducible and is ideal for preclinical studies on experimental intravesical therapies.</p>