Objective To evaluate the clinical significance of harmonic dissection of the cystic artery in laparoscopic cholecystectomy (LC). Methods Clinical data of 800 cases of LC from July 1999 to December 2000, in which a harmonic scalpel was used to directly coagulate and sever the cystic artery, were retrospectively analyzed. Results The surgery was completed smoothly in all the cases, without intra-or post-operative bleeding at the stump of the cystic artery. Pathological section examinations under microscope showed that high temperatures achieved by harmonic scalpel were great enough to make the arterial walls coagulated and the arterial lumens obstructed. Conclusions Harmonic dissection of the cystic artery in LC is safe and reliable.

In order to assess the cytotoxin effect of Campylobacter jejuni (C.jejuni), the whole cell lysates from 9 strains of Guillan-Barre Syndrome (GBS)- associated C.jejuni and 4 strains of diarrhea-associated C. jejuni were co-cultivated with HeLa cells at the concentration of 0.001-5.00 μg/mL in vitro. The morphologic change of HeLa cells was observed under Olympus BX51 microscope after treatment with different concentration of bacteria lysate in the following 4 days. The morphological changes including swelling, irregularity and lysis of the affected cells over 50% was selected as the cut off for positive change and C.jejuni 81-176 and Helicobacter J99 strains were chosen as the positive and negative control. It was found that the minimum concentration to induce the positive changes in 10 strains(8 GBS associated and 2 strains from diarrhea patients)was 0.1μg/mL and 1 strain with the positive change at the minimum concentration of 1 μg/mL. There was only one GBS-associated strain causing no morphologic change on HeLa cells at the concentration of 5 μg/mL. It was evident that the cytotoxic effect of C.jejuni strains on HeLa cell was strain-specific, and there was no significant difference in the cytotoxic effect on HeLa cell between GBS-associated and diarrhea associated C.jejuni strains.

The aim of this study is to develop the real-time PCR assays to detect and qualify C. coli from stool specimen. The primers and probe were designed based on the specific sequence of ceuE gene in C. coli using Primer 5.0 and Vector NTI Suite 6.0 e. The PCR assay was optimized with the reference C. coli strains. The standard curve based on the dilutions of genomic DNA showed a linear relationship between log CFU/mL and threshold cycles. The detectable limitation was 5.62 CFU/mL by using purified DNA from bacteria culture. The reproducibility of this assay was assessed by calculating the variation of the threshold cycle value and the slope from test repeats for the same strains and different strains. Our results indicate that the developed assay has high sensitivity and specificity for identification of C. coli.

Objective To assess the dignosis value of CT three-dimensional reconstruction with Fisher discriminant model in small solitary pulmonary nodules before operation.Methods CT data of 40 cases with SPN were retrospectively analyzed and divided into into malignant pulmonary nodules (25 cases),squamous cell carcinoma (4 cases),adenocarcinoma (13 cases),lung cancer (4 ca-ses),small cell lung cancer (2 cases),large cell carcinoma (1 case),metastases tumor (1 case),benign nodules (1 5 cases,6 cases of tuberculosis,2 cases of hamartoma,and 7 cases of non-specific inflammatory nodules)by pathology and follow-up results.The CT features of pulmonary nodules were evaluated through multi-planar reformation (MPR),curved-planar reformation (CPR),volume rendering (VR),maximum intensity proj ection (MIP)and other three-dimensional reconstruction.The three-dimensional data were divided into benign and malignant groups.In each of the two groups,the significant signs of morphological signs of discrimination indicators were adminstrated Fisher discriminant,and the probalitiy of false positives were estimated using cross-validation method. Results The positive features of pulmonary nodules in there-dismensional images were much more than in two-dimensional images. Fisher discriminant formula of solitary pulmonary nodules in three-dimensional images was Z=1.143X1 + 0.454X2+1.606X3-0.262X4+0.04X5+0.483X6+1.611X7-2.164.Discriminant boundary value Zc was-0.516.When Zcgreater than -0.516,nodules were proneed to considere as malignant nodules.In 25 cases of malignant nodules,4 cases mistook for benign.When Zc less than -0.516,nodules were proneed to considere as benign nod-ules.In 1 5 benign nodules,2 cases mistook for malignant.The total misdiagnosis and accuracy rate were 15 % and 85% respec-tively.Conclusion CT three-dimensional reconstruction combined with Fisher discriminant model have a high clinical value in dif-fereiating diagonsis of pulmonary nodules were proneed to considere as malignant nodules.In 25 cases of malignant nodules,4 cases mistook for benign.When Zc less than -0.516,nodules were proneed to considere as benign nodules. In 15 benign nodules,2 cases mistook for malignant.The total misdiagnosis and accuracy rate were 15 % and 85% respec-tively.Conclusion CT three-dimensional reconstruction combined with Fisher discriminant model have a high clinical value in differeiating diagonsis of pulmonary nodules.

OBJECTIVETo study the distribution of IS605, IS606 among clinical isolates of Helicobacter pylori in China.

METHODSA total of 104 H.pylori strains isolated from 5 different geographic regions in China were analyzed by PCR and dot-blot.

RESULTSForty-two strains out of the 104 isolates from 5 regions in China were found containing IS605 with 19 containing IS606. The frequency (66%) of IS605 positive strains from Yunnan province was higher than that from other areas. The different distribution of IS606 was neither associated with geographical regions nor with the presence of IS605 but IS606 were associated with the different clinical outcomes. However, the two reading frames ORFA and ORFB of IS605 were constantly coexisting.

CONCLUSIONIn China, IS605 and IS606 of H. pylori were widely existing but the presence of IS605 in H. pylori might be associated with geographic origin.

Objective:To understand the etiological characteristics of an acute gastroenteritis outbreak.Methods:Real-time polymerase chain reaction (PCR) and bacteria cultures were performed for the samples, including stool samples from patients and cooks, environmental swabs, raw food material (chicken meat), collected during the outbreak. Pulsed-field gel electrophoresis, antibiotics susceptibility test and whole-genome sequencing were performed for the Campylobacter jejuni isolates. Results:Four stool samples from patients were positive for Campylobacter jejuni by real-time PCR, in which 1 Campylobacter jejuni strain was isolated from a case who had no antibiotic treatment. Twelve Campylobacter jejuni and 7 Campylobacter coli isolates were obtained from 4 raw chicken meat samples. The Campylobacter jejuni strain isolated from the case was resistant to nalidixic acid, ciprofloxacin, chloramphenicol, florfenicol and tetracycline. The MLST analysis with the whole-genome sequences confirmed that the Campylobacter jejuni isolate from the case belonged to ST10075. Antimicrobial resistance genes cmeABCR, tetO/M and blaOXA-61 were found in the genome of the isolate from the patient by the whole-genome sequencing. No mutation in 23S rRNA was found and the C257T mutation in gyrA was identified in this isolate. Conclusion:Laboratory analysis indicated that Campylobacter jejuni infection might be the major cause of this gastroenteritis outbreak.

DraIII is a type IIP restriction endonucleases (REases) that recognizes and creates a double strand break within the gapped palindromic sequence CAC↑NNN↓GTG of double-stranded DNA (↑ indicates nicking on the bottom strand; ↓ indicates nicking on the top strand). However, wild type DraIII shows significant star activity. In this study, it was found that the prominent star site is CAT↑GTT↓GTG, consisting of a star 5' half (CAT) and a canonical 3' half (GTG). DraIII nicks the 3' canonical half site at a faster rate than the 5' star half site, in contrast to the similar rate with the canonical full site. The crystal structure of the DraIII protein was solved. It indicated, as supported by mutagenesis, that DraIII possesses a ββα-metal HNH active site. The structure revealed extensive intra-molecular interactions between the N-terminal domain and the C-terminal domain containing the HNH active site. Disruptions of these interactions through site-directed mutagenesis drastically increased cleavage fidelity. The understanding of fidelity mechanisms will enable generation of high fidelity REases.
Amino Acid Sequence ; Base Sequence ; Calorimetry, Differential Scanning ; Catalytic Domain ; Crystallography, X-Ray ; DNA ; metabolism ; DNA Cleavage ; Deoxyribonucleases, Type II Site-Specific ; chemistry ; genetics ; metabolism ; Escherichia coli ; metabolism ; Molecular Sequence Data ; Mutagenesis, Site-Directed ; Recombinant Proteins ; chemistry ; genetics ; metabolism ; Sequence Alignment ; Substrate Specificity

Nucleic acid sequence-based amplification and recombinase polymerase amplification are the recently developed thermostatic amplification techniques based on PCR. This paper briefly summarizes the principle of reaction, design principle of primer and probe, advantage of these two techniques (simple, accurate, highly sensitive and rapid) and introduces the application of the techniques in the detection of pathogenic bacteria.

Balancing the risks and benefits of organophosphate pesticides(OPs)on human and environmental health relies partly on their accurate measurement.A highly sensitive fluorescence anti-quenching multi-residue bio-barcode immunoassay was developed to detect OPs(triazophos,parathion,and chlorpyrifos)in apples,turnips,cabbages,and rice.Gold nanoparticles were functionalized with monoclonal antibodies against the tested OPs.DNA oligonucleotides were complementarily hybridized with an RNA fluorescent label for signal amplification.The detection signals were generated by DNA-RNA hybridization and ribonuclease H dissociation of the fluorophore.The resulting fluorescence signal en-ables multiplexed quantification of triazophos,parathion,and chlorpyrifos residues over the concen-tration range of 0.01-25,0.01-50,and 0.1-50 ng/mL with limits of detection of 0.014,0.011,and 0.126 ng/mL,respectively.The mean recovery ranged between 80.3％and 110.8％with relative standard deviations of 7.3％-17.6％,which correlate well with results obtained by liquid chromatography-tandem mass spectrometry(LC-MS/MS).The proposed bio-barcode immunoassay is stable,reproducible and reliable,and is able to detect low residual levels of multi-residue OPs in agricultural products.

Spinal cord injury (SCI) disrupts the structural and functional connectivity between the higher center and the spinal cord, resulting in severe motor, sensory, and autonomic dysfunction with a variety of complications. The pathophysiology of SCI is complicated and multifaceted, and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after SCI. Combinatory strategies targeting multiple aspects of SCI pathology have achieved greater beneficial effects than individual therapy alone. Although many problems and challenges remain, the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat SCI. In this review, we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following SCI at both the acute and chronic stages. In addition, we analyze the current status, remaining problems, and realistic challenges towards clinical translation. Finally, we consider the future of SCI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice. Going forward, clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeutic benefit in humans with SCI.
Humans ; Axons/pathology* ; Nerve Regeneration/physiology* ; Spinal Cord Injuries/therapy* ; Neurons/pathology* ; Recovery of Function