Objective To develop a method for rapidly identifying Clostridioides difficile(C.difficile)and de-termining high-producing toxin strains,conduct clinical evaluation.Methods The loop-mediated isothermal amplifi-cation(LAMP)method was used to identify C.difficile based on the tcdC,tcdA,and tcdB genes.The sensitivi-ty,specificity,and overall consistency of the detection method were evaluated.Results Feces specimens from 499 hospitalized patients suspected of C.difficile-associated diarrhea were detected,with C.difficile detection rate of 12.8％(64/499),out of which the detection rate of toxin-producing C.difficile was 10.8％(54/499).The sensi-tivity,specificity,positive predictive value,and negative predictive value of the detection method for tcdA were 87.2％,98.9％,89.1％,and 98.6％,respectively,and 88.2％,99.6％,90.0％,and 98.73％for tcdB,respec-tively.The total toxin levels of different strains were different,but the average toxin production level of A+B+strains(1.79 μg/mL)was higher than those of A-B+strains(0.72 μg/mL)and A-B-strains(＜0.10 μg/mL).Conclusion The portable high-throughput LAMP detection method can rapidly and efficiently identify C.difficile and determine high-producing toxin strains.

Objective To develop a method for rapidly identifying Clostridioides difficile(C.difficile)and de-termining high-producing toxin strains,conduct clinical evaluation.Methods The loop-mediated isothermal amplifi-cation(LAMP)method was used to identify C.difficile based on the tcdC,tcdA,and tcdB genes.The sensitivi-ty,specificity,and overall consistency of the detection method were evaluated.Results Feces specimens from 499 hospitalized patients suspected of C.difficile-associated diarrhea were detected,with C.difficile detection rate of 12.8％(64/499),out of which the detection rate of toxin-producing C.difficile was 10.8％(54/499).The sensi-tivity,specificity,positive predictive value,and negative predictive value of the detection method for tcdA were 87.2％,98.9％,89.1％,and 98.6％,respectively,and 88.2％,99.6％,90.0％,and 98.73％for tcdB,respec-tively.The total toxin levels of different strains were different,but the average toxin production level of A+B+strains(1.79 μg/mL)was higher than those of A-B+strains(0.72 μg/mL)and A-B-strains(＜0.10 μg/mL).Conclusion The portable high-throughput LAMP detection method can rapidly and efficiently identify C.difficile and determine high-producing toxin strains.

Objective To investigate the causes of recurrent hemoptysis one week after interventional treatment.Methods 56 patients with massive hemoptysis were included in this study.All patients underwent emergent interventional therapy, including angiography and embolization therapy of bronchial artery, intercostal artery, internal thoracic artery, external thoracic artery and phrenic artery via femoral artery puncture.Results 6 cases had rebleeding within one week after interventional therapy,including 2 cases with primary lung cancer,1 case with bronchiectasis,1 case with pulmonary tuberculosis,1 case with esophageal cancer after surgery,1 case with esophageal cancer after radiotherapy.Then, these patients once again underwent angiography and embolization therapy of bronchial artery,intercostal artery,internal thoracic artery,external thoracic artery and phrenic artery.Conclusion The use of vasoconstrictive drugs before intervention, diversification of pulmonary feeding artery, wide range of lesions, inappropriate embolic material and poor image quality can lead to recurrent hemoptysis after interventional treatment.

BACKGROUND:Cartilage extracelular matrix with a large number of signaling molecule proteins and factors is likely to be an ideal material for tissue engineering cartilage.
OBJECTIVE: To investigate the possibility of calcium alginate and cartilage extracelular matrix combined with microencapsulated stem cels derived from human umbilical cord Wharton’s jely to construct ectopic tissue-engineered cartilage in nude mice.
METHODS: Microfilament suspension of the cartilage extracelular matrix was prepared. Human stem cels derived from Wharton’s jely of the umbilical cord were inoculated in to calcium alginate and cartilage extracelular matrix gel microspheres as experimental group. Stem cels derived from human umbilical cord Wharton’s jely were incubated in simple alginate gel microspheres as control group. After in vitro culture, the microspheres wereimplanted into the dorsal subcutaneous tissue of nude mice. Samples were taken after 4 weeks, respectively, for gross and histological observation.
RESULTS AND CONCLUSION:The stem cels exhibited paralel-chondrocyte morphology in microspheres, which grew and proliferated quite wel during in vitro culture. A new paralel-cartilaginous tissue was found in the subcutaneous tissue 4 weeks after surgery in the experimental group, and the tissue was positive for hematoxylin-eosin, safranine O, toluidine blue and colagen II. A large number of paralel-chondrocytes and cartilage lacuna-like structures were observed under a microscope with no obvious inflammatory reaction around the microspheres. The control group showed the partial degradation of microspheres, surrounded by only a smal number of inflammatory cels and lymphocytes. Calcium alginate and cartilage extracelular matrix microspheres have a rather good histocompatibility which can be used to construct paralel-cartilaginous tissues by implanting stem cel-microspheric compound into the subcutaneous tissue of nude mice.

Background and purpose: Regional lymph node metastasis was significantly associated with the prognosis of patients with non-small cell lung cancer (NSCLC). This study was designed to compare paclitaxel liposome plus cisplatin (LP) with gemcitabine and cisplatin (GP) in patients with regional lymph node metastasis of advanced NSCLC as a ifrst-line treatment. Methods:A total of 55 patients were randomly assigned to receive either liposomal paclitaxel (175 mg/m2) and cisplatin (75 mg/m2) or gemcitabine (1 000 mg/m2) and cisplatin (75 mg/m2) every 3 weeks. Results:Objective response rate (ORR) of lung primary foci was 37.9%in the LP arm and 30.8%in the GP arm (P>0.05) and the disease control rate (DCR) was 91.3%and 80.8%respectively (P>0.05);ORR of regional metastasis lymph node was higher in the LP arm (44.8%vs 15.4%, P<0.05).There was no signiifcant difference in DCR (93.1%vs 73.1%, P=0.101), although slight trends favoring paclitaxel liposome were seen;There was signiifcant difference in median overall survival (17.0 vs 12.0 months, P<0.05). LP was associated with significantly less thrombocytopenia and gastrointestinal side effects (P<0.05), but no signiifcant difference was observed in hyphemia, leucopenia, hepatotoxicity, renal toxicity and allergic reactions (P>0.05). Conclusion: Liposomal paclitaxel plus cisplatin is superior to gemcitabine plus cisplatin with less toxicity and better tolerated, it deserves further research and clinic application for patients with regional lymph node metastasis of advanced NSCLC.

BACKGROUND:Titanium implants as a safe biological material have been used to produce the artificial Russian titanium cornea, but complications stil exist, including artificial cornea shift, leakage, corneal tissue melting and artificial cornea discharge.
OBJECTIVE:To evaluate in vivo biocompatibility of hydroxyapatite modified titanium skirt for keratoprosthesis in alkali burn cornea.
METHODS:A total of 30 alkali burned New Zealand white rabbit corneas were divided into three group groups. Hydroxyapatite modified titanium skirt (experimental group) and titanium skirt (control group) were respectively inserted into the corneal stroma of rabbits. In the blank control group, only a lamel ar corneal incision was made.
RESULTS AND CONCLUSION:Al skirts were stable without necrosis, melting and exclusion during the observation period. The number of inflammatory cells in the experimental and control groups was significantly higher than that in the blank control group at 2 and 8 weeks postoperatively (P<0.05), but there was no difference in inflammatory cellinfiltration among different groups by the 16th week. The number of corneal fibroblasts increased significantly in the experimental group compared with the control and blank control group after 2, 8, 16 weeks (P<0.05). The extracellular matrix deposited on the surface of hydroxyapatite modified titanium skirt was denser and tighter than that on the surface of titanium skirt. It indicates that hydroxyapatite modified titanium skirt for keratoprosthesis can promote the interfacial biointegration of skirt and host cornea.

Objective To probe the blood supply of liver metastasis by celiac artery,proper hepatic artery DSA.portal vein perfusion CT during superior mesenteric arterial poaography(PCTAP).Methods One hundred patients with liver metastases were examined prospectively by plain CT scan,multiphase enhanced CT scan,celiac arteriography and proper hepatic artefiography.Of them,56 patients were examined by PCTAP.All primary lesions wero confirmed by operation and(or)pathology examination.In order to investigate the blood supply of metastasis lesions.the software of Photoshop Was used to obtain the time-attenuation cugves(TDC)of tumor center,tumor edge,portal vein and normal liver parenchyma adjacent to the tumor to talculate liver perfusion for DSA image analysis,while a deconvolution model from CT perfusion software Was designed for the dual blood supply.Results DSA findings:TDC of proper hepatic arteriography showed:the mean peak concentration(K value)in tumor centers was(67±12)%,and it was(76±15)%for peritumor tissue,(51±10)%in normal liver parenchyma.TDC of celiac arteriogaphy showed that the contrast concentration of tumor centers and tumor edge increased fast in early stage.then maintained a slight upward plateau,in the meanwhile,the contrast concentration of normal liver parenchyma kept increasing slowly.PCTAP findings:tumors exhibited no enhancement during 30 s continued scans.Conciusion The blood supply of liver metastasis mainly comes from hepatic artery,but barely from portal vein.

BACKGROUND:Choose an ideal vector for amplified chondrocytes arouses more and more attention during the construction of epiphyseal cartilage tissue engineering. OBJECTIVE:To explore the feasibility and performance of epiphyseal cartilage tissue engineering scaffold constructed by chitosan and extracellular matrix of cartilage. DESIGN,TIME AND SETTING:An in vitro study was performed at Department of Orthopedics,General Hospital of Chinese PLA from December 2007 to March 2003. MATERIALS:Chitosan(deacetylation:90%;Mr10?105) was provided by Haihui Bioengineering Company,Qingdao;articular cartilage of swine was collected from market. METHODS:Fresh porcine articular cartilages were obtained and shattered in the iso-osmia liquid. After pulverization and gradient centrifugation,3% artilage microfilament suspension was equally mixed with 2% chitosan. Three-dimensional porous scaffolds were fabricated using a simple freeze-drying method. MAIN OUTCOME MEASURES:After the second gradient ethanol treatment,the scaffolds were investigated by histological staining and scanning electron microscopy to measure aperture,porosity,and water absorption rate. MTT test was also done to assess cytotoxicity of the scaffolds. After induced by transforming growth factor-?1(TGF-?1) ,bone marrow mesenchymal stem cells(BMSCs) of rabbits were incubated onto the scaffolds. Cell proliferation and differentiation were analyzed using inverted microscopy and scanning electron microscopy. RESULTS:The three-dimensional porous scaffold had good pore interconnectivity with pore diameter(161?31) ?m,(90.1?1.6) % porosity and(2 361?132) % water absorption rate. The histological staining showed that toluidine blue,safranin O and anti-collagen II immunohistochemistry staining were positive. The intrinsic cytotoxicity assessment of the scaffolds using MTT test showed that the scaffolds had no cytotoxic effect on BMSCs. Most of the BMSCs attached and covered the surface of the scaffolds with matrix secretion. CONCLUSION:The three-dimensional porous scaffold constructed by extracellular matrix of cartilage and chitosan has good pore diameter and porosity,non-toxicity and good biocompatibility,so it is a suitable scaffold for epiphyseal cartilage tissue engineering.

BACKGROUND:Because human cells for culturing alveolar bone cell line are from alveolar bone, which is in oral cavity,and easily polluted, so laboratory study is often unsuccessful. Because the samples are from adults, so cell division index and the successful rate of culture are low.OBJECTIVE: To compare the biological characteristics of survived cell line established through passage,cryopreservation and revitalization following in vitro culturing the alveolar bone tissue obtained from normal persons and patients with chronic periodontitis accompanied with osteoporosis in aseptic operation; To compare the biological characteristics of two kinds of cells so as to provide theoretical and related experimental evidence for defect, repair and treatment of alveolar bone.DESIGN: Controlled observation.SETTING: Department of Stomatology, Beijing Chaoyang Hospital, Capital Medical University; Institute of Orthopaedics,General Hospital of Chinese PLA.MATERIALS: Alveolar bone tissue obtained from normal persons and patients with chronic periodontitis confirmed in clinic was used in aseptic operation.METHODS: Alveolar bone tissue from normal persons and chronic periodontitis accompanied with osteoporosis were cultured in vitro. In the four cell lines (H-171, H-258, 261, 262) cultured primarily, cell lines H-171 and H-258 were chosen from periodonitis patients group and normal group respectively, and stained with histochemical and immunohistochemical methods. Cell morphology was observed. Doubling time and division index of two kinds of cells were calculated with cytometry. After several circles of passage, cryopreservation and revitalization, growth and aging rule of cells were compared.MAIN OUTCOME MEASURES: Passage and biological characteristics of two groups of cell lines.RESULTS: ①In the abnormal alveolar bone group, there was one successful primary culture and cells presented short-spindle shape. There were 3 times of cryopreservation and 3 times of revitalization. Its doubling time was 53.4 hours. The average division index was about 4‰. Cells well grew after 20 times of passages. ②In the normal alveolar bone group, there were 26 cases of cell lines cultured primarily, but passage was found in only 3 cases of cell lines due to various causes. There were 10 passages and the cells presented long-spindle shape. After two circles of cryopreservation and revitalization, the survival and growth rate of cells were inferior as compared with cell line H-171.Doubling time was 65.9 hours and the average division index was 3.5‰. ③Both two kinds of cells adhered the wall, with the characteristics of osteoblasts: AKP, toluidine blue, PAS, tetracycline-labeled mineralized nodus, type Ⅰ collagen and BMP-2 immunohistochemical staining all presented positive.CONCLUSION: Both two kinds of cultured cells have the characteristics of osteoblasts. The growth speed of cell line H-171 is faster than that of cell line H-258. No obvious mutation is found in 20 passages. In the 8th generation of H-258,aging appears and growth speed becomes slow.