An effective fingerprint orientation field estimation method using differential values of grayscale intensity.

Fingerprint orientation field (OF) estimation is important for basic fingerprint image processing and impacts the accuracy of fingerprint image enhancements, such as Gabor filters. In this article, we introduce an OF estimation algorithm based on differential values of grayscale intensity and examine the accuracy and reliability of the proposed algorithm by applying it to fingerprint images processed using Gaussian blurring and the Gaussian white noise process. The experimental results indicate that the OF estimation reliability of the proposed algorithm is higher than the gradient-based method and the power spectral density (PSD) based method in low quality fingerprints. The proposed algorithm is especially useful in noisy fingerprint images, where the OF estimation reliability of the algorithm is 6.46% and 32.93% higher than the gradient-based method and the PSD-based method, respectively.

The Enhanced Thermal Stability of (Mg0.95Ni0.05)2TiO4 Dielectric Ceramics Modified by a Multi-Phase Method.

The thermal stability of (Mg0.95Ni0.05)2TiO4 dielectric ceramics has been improved by mixing with CaTiO3 phases owing to higher positive temperature coefficients. The pure (Mg0.95Ni0.05)2TiO4 and the mixture phase systems of CaTiO3-modified (Mg0.95Ni0.05)2TiO4 were verified by XRD diffraction patterns to ensure the crystallite of different phases. The microstructures of the CaTiO3-modified (Mg0.95Ni0.05)2TiO4 were observed by SEM and EDS to investigate the relation between element ratios and grains. As a result, it can be seen that the thermal stability of the CaTiO3-modified (Mg0.95Ni0.05)2TiO4 can be effectively enhanced, compared with the pure (Mg0.95Ni0.05)2TiO4. Moreover, the radio frequency dielectric performances of CaTiO3-modified (Mg0.95Ni0.05)2TiO4 dielectric ceramics are strongly dependent upon the density and the morphology of the specimens. The champion sample with the ratio of (Mg0.95Ni0.05)2TiO4 and CaTiO3 of 0.92:0.08 showed an εr value of 19.2, an Qf value of 108,200 GHz, and a τf value of -4.8 ppm/°C, which may encourage (Mg0.95Ni0.05)2TiO4 ceramics to broaden the range of novel applications and match the requirements of 5G or next-generation communication systems.

Experimental results and mathematical formulation of non-spinning stone-skipping process.

Following a previously published paper in studying stone-skipping processes, detailed experimental figures are revealed in this paper. A mathematical model is also provided to explain the observed phenomena and measured data. The model separates the skipping process into several stages. It emphasizes, in particular, a hitting stage and a sliding stage, and also includes capillary-gravity wave resistance in its formulation. During these two stages, scale analysis is applied first to evaluate the relative importance among various forces acting on the stone. After reasonable simplification, a numerical algorithm is established to depict motion of the stone starting from its first hit of water to final sink. The total number of skips under specified initial throwing conditions can be predicted accordingly. The agreement between the analytical and experimental results indicates the applicability of the proposed model.

Association between magnetic resonance imaging of carotid artery and coronary stenosis detected by computed tomography angiography.

OBJECTIVE: To investigate the correlation between carotid artery stenosis (CAS) measured by magnetic resonance imaging (MRI) and the coronary stenosis (CS) determined by computed tomography angiography (CTA). METHODS: In this prospective study, 42 subjects diagnosed with coronary artery disease (CAD) underwent MRI and CTA examinations. The severity degree and number of CAS, the score, detection rate and type of carotid plaque, and also the severity degree and number of CS were assessed. Spearman's rank correlation test was used to evaluate the correlation between CAS and CS. RESULTS: CS was detected in 42 (100%) subjects, while CAS was detected in 36 (85.7%) subjects. Distribution of CAS severity grades in multiple-vessel group was significantly different from other groups, which with more moderate and severe stenosis (p < 0.05). A positive and significant correlation between the CAS severity and CS severity (r = 0.612, p < 0.05), and the number of involved coronary vessels (r = 0.572, p < 0.05) were observed, respectively. Both detection rate (r = 0.587, p < 0.05) and score (r = 0.735, p < 0.05) of carotid plaque showed a good correlation with the number of involved coronary vessels. After carotid MRI, 71 carotid plaques were detected in 42 subjects, with an incidence rate of 9.9% in subjects with mild CS, 18.3% in moderate CS and 71.8% in severe CS. CONCLUSION: Correlation between CAS measured by MRI and CS determined by CTA was identified in present study. These results indicated that the non-invasive CAS evaluation employing the MRI may be clinically useful for the assessment of CS.

Left and right ventricular function detection and myocardial deformation analysis in heart transplant patients with long-time follow-ups.

OBJECTIVE: We try to investigate whether the values of longitudinal strain present differences between the left and right ventricles in long-time follow-ups after heart transplantation (HTx) with dynamic changes in function. METHODS AND RESULTS: Follow-up transthoracic echocardiography was performed in 1- and 3-month and 1- and 5-year follow-ups in 50 "healthy" HTx patients and compared with 26 control subjects. The left ventricle with preserved ejection fraction evaluated by biplane Simpson (control group [CG] vs HT; P > .05) had an obvious reduction in global (CG: -20.49 ± 2.38 vs heart transplant 1 month [HT1m]: -13.06 ± 2.86, heart transplant 3 month [HT3m]: -13.61 ± 2.61, heart transplant 1 year [HT1y]: -13.69 ± 4.56, heart transplant 5 year [HT5y]: -14.41 ± 4.54; P < .001) and horizontal segmental (basal, mid, apical) (P < .001) together with chamber segmental (apical 4-chamber, apical 3-chamber, apical 2-chamber) (P < .001) average strain values. The right ventricle with reduced ventricular function measured by tissue Doppler imaging S' and tricuspid annular plane systolic excursion had a more distinctive reduction in global (CG: -24.53 ± 4.20 vs HT1m: -12.94 ± 5.03, HT3m: -13.68 ± 4.35, HT1y: -14.95 ± 7.50, HT5y: -15.20 ± 6.15; P < .001) with segmental lateral (P < .001) strain values. There were not any significant changes between 1- and 3-month follow-ups of all the values (P > .05). But it could be seen that values increased in 1- and 5-year follow-ups compared with the baseline of 1- and 3-month follow-ups (P < .05). The global and segmental strain of the right ventricle decreased more than that of the left ventricle in all HTx groups, and the strain values were decreased in the HTx groups compared with the CG, with the global decreased change rates being 11%, 10%, 6%, and 8%, respectively. CONCLUSIONS: The strain values decreased after HTx and almost remained stable in the long-time follow-ups. Compared with the CG in both ventricles, they were with preserved or reduced functions. In addition, the deformation values of the right ventricle decreased more than those of the left.

Half-Metallic Property Induced by Double Exchange Interaction in the Double Perovskite Bi2BB'O6 (B, B' = 3d Transitional Metal) via First-Principles Calculations.

In this paper, we identify three possible candidate series of half-metals (HM) from Bi-based double perovskites Bi2BB'O6 (BB' = transition metal ions) through calculations utilizing the density functional theory (DFT) and full-structural optimization, in which the generalized gradient approximation (GGA) and the strong correlation effect (GGA + U) are considered. After observing the candidate materials under four types of magnetic states, i.e., ferromagnetic (FM), ferrimagnetic (FiM), antiferromagnetic (AF), and nonmagnetic (NM), we found eight promising candidates for half-metallic materials. Under the GGA scheme, there are three ferromagnetic-half-metal (FM-HM) materials, Bi2CrCoO6, Bi2CrNiO6 and Bi2FeNiO6, and three FiM-HM materials, Bi2FeZnO6, Bi2CrZnO6 and Bi2CoZnO6. With implementation of the Coulomb interaction correction (GGA + U), we find two stable half-metallic materials: Bi2CrNiO6 and Bi2CrZnO6. We determine that the stability of some of these materials are tied to the double exchange interaction, an indirect interaction within the higher powers of localized spin interaction among transition metals via oxygen ions. Found in half-metallic materials, and especially those in the ferromagnetic (FM) state, the double exchange interaction is recognized in the FM-HM materials Bi2CrCoO6 and Bi2FeNiO6.

Assessment of Left Ventricular Myocardial Viability by 3-Dimensional Speckle-Tracking Echocardiography in Patients With Myocardial Infarction.

OBJECTIVES: To determine whether 3-dimensional (3D) speckle-tracking echocardiography could provide a new way to assess myocardial viability in patients with myocardial infarction (MI). METHODS: Forty-five patients with MI underwent routine echocardiography, 2-dimensional (2D) speckle-tracking echocardiography, and 3D speckle-tracking echocardiography. Radionuclide myocardial perfusion/metabolic imaging was used as a reference standard to define viable and nonviable myocardia. RESULTS: Among 720 myocardial segments in 45 patients, 368 showed abnormal motion on routine echocardiography; 204 of 368 were categorized as viable on single-photon emission computed tomography/positron emission tomography (SPECT/PET), whereas 164 were defined as nonviable; 300 normal segments on SPECT/PET among 352 segments without abnormal motion on routine echocardiography were categorized as a control group. The radial, longitudinal, 3D, and area strain on 3D speckle-tracking echocardiography had significant differences between control and nonviable groups (P < .001), whereas none of the parameters had significant differences between control and viable groups. There were no significant differences in circumferential, radial, and longitudinal peak systolic strain from 2D speckle-tracking echocardiography between viable and nonviable groups. Although there was no significant difference in circumferential strain between the groups, radial and longitudinal strain from 3D speckle-tracking echocardiography decreased significantly in the nonviable group. Moreover, 3D and area strain values were lower in the nonviable segments than the viable segments. By receiver operating characteristic analysis, radial strain from 3D speckle-tracking echocardiography with a cutoff of 11.1% had sensitivity of 95.1% and specificity of 53.4% for viable segments; longitudinal strain with a cutoff of 14.3% had sensitivity of 65.2% and specificity of 65.7%; 3D strain with a cutoff of 17.4% had sensitivity of 70.6% and specificity of 77.2%; and area strain with a cutoff of 23.2% had sensitivity of 91.5% and specificity of 82.8%. CONCLUSIONS: Three-dimensional speckle-tracking echocardiography might have potential for detection of myocardial viability in patients with cardiac dysfunction due to MI.

Constructing an effective prevention mechanism for MSW lifecycle using failure mode and effects analysis.

Municipal solid waste in Taiwan is a valuable source of renewable energy. Phases of municipal solid waste lifecycle (classification, disposal, storage, collection and transportation) before incineration or landfilled face various potential failures. Applying a proper technique to eliminate or decrease potential failures is desirable and needed. Failure Modes and Effects Analysis to municipal solid waste lifecycle was found in literature. This study utilized the Failure Modes and Effects Analysis as a convenient technique for determining, classifying and analyzing common failures in the municipal solid waste lifecycle. As a result, an appropriate risk scoring of severity, occurrence, and detection of failure modes and computing the Risk Priority Number for identifying the high potential failure modes were made. Nineteen failure modes were identified, and nine of them were ranked as the priority items for improvement. Recommended actions for all failure modes were suggested. Occurrences of failures were remarkably reduced after implementing the procedure for six months. The results of this study have minimized potential failures and brought continuous improvement, thus achieving a better protection of the environment.

[Viable myocardium evaluation by two dimensional speckle tracking imaging combined with adenosine stress echocardiography].

OBJECTIVE: Regional left ventricular (LV) function could be detected by measuring peak-systolic strain by speckle tracking imaging (STI). We evaluated the value of STI combined with adenosine stress echocardiography on assessing myocardial viability in patients with myocardial infarction (MI). METHODS: Two dimensional echocardiography was performed at rest and after adenosine stress echocardiography (infused at 140 µg×kg(-1)×min(-1) over a period of 6 min) in 39 stable patients with previous MI. Peak-systolic (Speak-sys) circumferential strain, radial strain and longitudinal strain were assessed by STI. Radionuclide myocardial perfusion/metabolic imaging served as the "gold standard" to detection of myocardial viability. RESULTS: (1) There were 215 viable and 153 non-viable regions among 368 abnormal motion segments out of 624 segments in 39 MI patients according to radionuclide imaging results. (2) Speak-sys was similar between viable and nonviable myocardium at rest (all P > 0.05). After adenosine infusion, radial Speak-sys [(37.98 ± 5.45)% vs. (30.22 ± 5.47)%], longitudinal Speak-sys [(-23.71 ± 4.53)% vs. (-17.52 ± 4.34)%] increased significantly (P < 0.05)in viable segments compared to baseline levels and were significantly higher than in nonviable segments radial Speak-sys [(37.98 ± 5.45)% vs. (30.12 ± 5.37)%] and longitudinal Speak-sys [(-23.71 ± 4.53)% vs. (-16.95 ± 4.62)%] (P < 0.05), while remained unchanged in nonviable segments before and after adenosine infusion. Circumferential Speak-sys was similar before and after adenosine infusion in both viable and nonviable segments (all P > 0.05). (3) Delta radial strain change > 9.8% has a sensitivity of 82.3% and a specificity of 81.1% whereas a delta change of longitudinal strain > 16.5% has a sensitivity of 83.5% and a specificity of 92.3% for detecting viable segments. CONCLUSIONS: Speckle tracking imaging combined with adenosine stress echocardiography could serve as a new and reliable method of assessing myocardial viability.

Clinic value of two-dimensional speckle tracking combined with adenosine stress echocardiography for assessment of myocardial viability.

BACKGROUND: To evaluate whether myocardial strain under adenosine stress calculated from two-dimensional echocardiography by automatic frame-by-frame tracking of natural acoustic markers enables objective description of myocardial viability in clinic. METHODS AND RESULTS: Two-dimensional echocardiography and two-dimensional speckle tracking imaging (2D STI) at rest were performed first and once again after adenosine was infused at 140 ug/kg/min over a period of 6 minutes in 36 stable patients with previous myocardial infarction. Then radionuclide myocardial perfusion/metabolic imaging served as the "gold standard" to define myocardial viability was given in all patients within 1 day. Two-dimensional speckle tracking images were acquired at rest and after adenosine administration. An automatic frame-by-frame tracking system of natural acoustic echocardiographic markers was used to calculate 2D strain variables including peak-systolic circumferential strain (CS(peak-sys)), radial strain (RS(peak-sys)), and longitudinal strain (LS(peak-sys)). Those segments with abnormal motion from visual assessment of two-dimensional echocardiography were selected for further study. As a result, 126 regions were viable whereas 194 were nonviable among 320 abnormal motion segments in 36 patients according to radionuclide imaging. At rest, there were no significant changes of 2D strain between the viable and nonviable myocardium. After adenosine administration (140 ug/kg/min), CS(peak-sys) had a little change of the viable myocardium while RS(peak-sys) and LS(peak-sys) increased significantly compared with those at rest. In nonviable group, CS(peak-sys), RS(peak-sys), and LS(peak-sys) had no significant changes during adenosine administration. After adenosine administration, RS(peak-sys) and LS(peak-sys) in viable group increased significantly compared with nonviable group. Obtained strain data were highly reproducible and affected in small intraobserver and interobserver variabilities. A change of radial strain more than 9.5% has a sensitivity of 83.9% and a specificity of 81.4% for viable whereas a change of longitudinal strain more than 14.6% allowed a sensitivity of 86.7% and a specificity of 90.2%. CONCLUSIONS: 2D STI combined with adenosine stress echocardiography could provide a new and reliable method to identify myocardium viability.

[Development of glipizide push-pull osmotic pump controlled release tablets by using expert system and artificial neural network].

The purpose of this study is to develop glipizide push-pull osmotic pump (PPOP) tablets by using a formulation design expert system and an artificial neural network (ANN). Firstly, the expert system for the formulation design of osmotic pump of poor water-soluble drug was employed to design the formulation of glipizide PPOP, taking the dissolution test results of Glucotrol XL as the goal. Then glipizide PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. And in vivo evaluation was carried out between the samples which were similar to Glucotrol XL and the Glucotrol XL in Beagle dogs. The range of the factors of formulation and procedure, which could influence the drug release, was optimized using artificial neural network. Finally, the design space was found. It was found that the target formulation which was similar to Glucotrol XL in dissolution test could be obtained in a short period by using the expert system. The samples which were similar to Glucotrol XL were bio-equivalent to the Glucotrol XL in Beagle dogs. The design space of the key parameter coating weight gain was 9.5%-12.0%. It could be concluded that a well controlled product of glipizide PPOP was developed since the dissolution test standard of our product was more strict than that of Glucotrol XL.

[Improved therapeutic effectiveness by combining recombinant human RhoB with low-dose cisplatin in human lung cancer in nude mice].

OBJECTIVE: To determine the antitumor effects of the recombinant human RhoB with low-dose cisplatin in lung carcinoma models. METHODS: The pVITRO2-RhoB recombinant was constructed and transfected into A549 cells. Its expression and the inhibition effect to the A549 cells were observed models. A549 lung carcinoma mice were treated with either RhoB or cisplatin or both agents together. And the change of tumor size, the survive time of mice, the apoptosis of tumor were also observed. RESULTS: The pVITRO2-RhoB recombinant was constructed successfully. This recombinant could inhibit the growth and promote the apoptosis of A594 in vitro. Mice treated with RhoB or low-dose cisplatin treatment individually resulted in tumor inhibition to a certain extent. Mice treated with combination of RhoB and low-dose cisplatin resulted in synergistic antitumor activity with more effective tumor inhibition (P < 0.05) and longer survival (P < 0.05). TUNEL analysis of tumors exhibited that RhoB in combination with cisplatin led to the increased rate of apoptosis (P < 0.05). CONCLUSION: Our data demonstrated that RhoB could increase the sensitivity of lung carcinoma to cisplatin, resulting in enhanced anti-tumor activity. These results suggest that combination with recombinant human RhoB with chemotherapy drugs may be an effective approach in the treatment of lung carcinoma.

[Design push-pull osmotic pump tablets of famotidine based on an expert system for the formulation design of osmotic pump of poor water-soluble drug].

The purpose of this study is to design push-pull osmotic pump (PPOP) tablets of famotidine using the expert system for the formulation design of osmotic pump of poor water-soluble drug which had been established by the authors. Firstly, the parameters which were requisite of the system input were obtained from literatures and experimental tests. Then the parameters were input into the system, and the program was run. The system displayed the designed formulations sequential. Finally, famotidine PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. It was found out that the target formulation of famotidine PPOP which could release for 24 hours was obtained in a very short period. Meanwhile, the practicability of the established expert system was proved.

Development of glycyrrhetinic acid-modified stealth cationic liposomes for gene delivery.

The glycyrrhetinic acid-modified stealth cationic liposomes (GA-PEG-CLs) loaded with pDNA (GA-PEG-CLPs) were developed and found to transfect human hepatocellular carcinoma cell line HepG2 with high efficiency. GA-PEG-CLs were comprised of DOTAP, cholesterol (Chol) and glycyrrhetinic acid-polyethyleneglycol-cholesterol conjugate (GA-PEG-Chol). Agarose gel electrophoresis revealed that 5% GA-PEG-CLs constituted by DOTAP/Chol/GA-PEG-Chol at molar ratio of 50:45:5 could completely entrap pDNA at a lower liposomes/pDNA weight ratios of 4:1 (N/P ratio: 1.14). Compared to ordinary cationic liposomes (CLs), steric cationic liposomes (PEG-CLs) and 1% GA-PEG-CLs made from DOTAP/Chol/MPEG2000-Chol/GA-PEG-Chol at molar ratio of 50:45:4:1, 5% GA-PEG-CLs were found to possess the highest transfection efficiency as gene vectors in serum-free or serum-containing medium in PKCalpha over-expressed HepG2 cells but no significance difference in human embryonic kidney cell line HEK 293. Additionally, 5% GA-PEG-CLs have the lowest cytotoxicity on human normal hepatocyte cell line L02. The competitive inhibition experiments mediated by GA were carried out in HepG2 cells, which demonstrated that GA-PEG-CLs could deliver selectively pDNA to hepatoma cells by the targeting moiety GA. In conclusion, GA-PEG-CLs containing 5% GA-PEG-Chol might be one of the most potential gene vectors as hepatoma targeting therapy.

[Association between urinary neutrophil gelatinase-associated lipocalin and acute kidney injury after cardiac surgery].

OBJECTIVE: To test the hypothesis that Neutrophil gelatinase-associated lipocalin (NGAL) is an early biomarker for acute kidney injury (AKI) in patients after cardiac surgery. METHODS: 33 cases undergoing cardiac surgery were divided into AKI group and Non-AKI group according to the AKI criteria. The concentration of urine NGAL at different time points were measured. RESULTS: (1) Nine of 33 cases (27%) developed postoperative AKI, but diagnosis with serum creatinine was only 12-48 hours after cardiac surgery. (2)Urinary concentrations of NGAL at 2 h after cardiac surgery in patients who did not developed AKI were significantly higher compared with those of preoperative (P < 0.001). Urinary concentrations of NGAL at 2 h and 4 h after cardiac surgery in patients who developed AKI were significantly higher compared with those of preoperative (P < 0.001). (3) The mean urinary NGAL concentrations in patients who developed AKI were significantly higher after surgery compared with patients who did not develop AKI (P < 0.01). (4) Urinary concentrations of NGAL/Ucr at 2 h and 4 h after cardiac surgery in patients who did not developed AKI were significantly higher compared with those of preoperative (P < 0.05). Urinary concentrations of NGAL/Ucr at 2 h and 4 h after cardiac surgery in patients who developed AKI were significantly higher compared with those of preoperative (P < 0.01). (The mean urinary concentrations of NGAL/Ucr in patients who developed AKI were significantly higher after surgery compared with patients who did not develop AKI (P < 0.01). (6) For concentrations in urine of NGAL at 2 h after surgery, sensitivity was 0.7125, and specificity was 0.7307 for a cutoff value of 250 microg/L. For concentrations in urine of NGAL/Ucr at 2 h after surgery, sensitivity was 0.8127, and specificity was 0.7839 for a cutoff value of 250 microg/mmol. (7) Urinary concentrations of NGAL at 2 h after cardiac surgery was significantly associated with serum creatinine 12 h postoperative (R = 0.638, P < 0.05). CONCLUSIONS: The incidence of AKI in patients after cardiac surgery is high, which accounted for 27%. The amount of NGAL and NGAL/Ucr in urine at 2 h after cardiac surgery were the powerful independent predictor of acute renal injury and urine concentrations of NGAL/Ucr is more sensitive.

[Survival analysis on liver failure patients treated with an artificial liver support system].

OBJECTIVE: To evaluate the efficacy of artificial liver support system (ALSS) in the treatment of liver failure patients. METHODS: This is a prospective, multi-center, controlled, large sample clinic trial. 518 patients with liver failure from 5 hospitals were studied and followed. All the patients received similar pharmacological manipulation according to one and the same protocol but were divided into an ALSS treatment group and a control group without ALSS treatment. The ALSS treatment procedures included plasma exchange, molecular adsorbent recirculating system (MARS), plasma exchange plus hemofiltration and other combined nonbioartificial methods. The analysis of survival time was computed using the Kaplain-Maier method, and comparison among groups was done using Log-Rank, Breslow and/or the Tarone-Ware test. RESULTS: Survival time of acute liver failure patients was prolonged from 4.0+/-0.2 days to 8.0+/-0.4 days (P=0.004). ALSS was shown to be two times more effective. ALSS increased the survival time of acute on chronic (A on C) liver failure patients from 27.0+/-1.6 days to 39.0+/-4.0 days (P less than 0.01). In addition, it increased the survival time of the patients in the middle and end stage of subacute liver failure and A on C liver failure, but had no significant effects on early stage patients. The survival time of middle stage patients was 38.0+/-17.5 days in the control group vs 66.0+/-18.6 days in the ALSS group (P less than 0.05). The survival time of end stage patients of the control group and the ALSS group was 18.0+/-4.0 days vs 26.0+/-2.5 days (P less than 0.01). CONCLUSIONS: Multi ALSS treatment is more effective than the standard medicinal liver care treatment. Multi-ALSS treatment could increase survival time of patients suffering from acute liver failure or A on C liver failure, especially in their middle and end stages. It is important and necessary to treat these patients with ALSS.

[The construction and expression of superantigen SEA and antimelanoma ScFv fusion gene].

Two strategies, direct ligation after enzyme digestion and over-lap PCR technology, were adopted to construct a fusion gene which was composed of the antimelanoma single chain antibody gene and the staphylococcal enterotoxin A gene without N-terminal signal sequence. The fusion gene was subcloned into pET28-a vector and transformed into E. coli BL21(DE3). Ni-NTA system was selected to separate and purify the expresstd products. The inhibition ratio of the fusion protein was tested by MTT method. It is shown that the 6His-ScFv-SEA fusion protein can be expressed stably in E. coli BL21 (DE3). The quantity of the fusion protein was shown up to 30% of the total protein of the bacteria and mainly in inclusion body. By activation the effective cells, the fution protein can inhibit the melanoma cell whith expressed corresponding antigen.

[The changes of rare codons increase expression level of SEA].

The rare codons of a fragment in staphylococcal enterotoxin A gene were turned into the most high usage frequency codons in E. coli by overlap PCR technique. Genes of sea and seam were cloned into 7ZTS expression vector and transformed into JM109(DE3), respectively. The result shows that expression level of sea gene was very low, but the expression level of seam was as high as 15% of total cell proteins. The expression product shows activity of antitumor in vivo.

[Cloning of staphylococcal enterotoxin B gene and its highly expression in Escherichia coli].

An about 700 bp DNA fragment was amplified from genome DNA of S. aureus TSTw by PCR. This fragment was cloned into pGEM-7Zf(+) and the recombinant plasmid was transformed into E. coli DH5 alpha. The sequencing result of the recombinant plasmid demonstrated that it contains seb gene with 717 bp (without signal encoding region of 81 bp) which has the same nucleotide sequence as described in literature. The seb gene was cloned into expression vector 7ZTS and was transformed into E. coli JM109 (DE3). The expression level of SEB was as high as 33.3% of the cell total proteins.