Underactuated AUV Nonlinear Finite-Time Tracking Control Based on Command Filter and Disturbance Observer.

The three-dimensional (3D) path following problem of an underactuated autonomous underwater vehicle with ocean currents disturbances is addressed in this paper. Firstly, the motion equation under the ocean currents disturbance is established, and the dynamic model of 3D tracking error is constructed based on virtual guidance method. Then, a finite-time control scheme based on super-twisting observer and command filtered backstepping technology is proposed. We adopt super-twisting observer based on finite-time theory to observe the ocean currents disturbances for improving the system robust. A command filtered backstepping is proposed to replace the differential process in the conventional backstepping method for avoiding the differential expansion problem. The filter compensation loop is designed to ensure the accuracy of the filtered signal, and the anti-integration saturation link is designed considering the influence of integral saturation. Lyapunov stability theory is used to prove the stability of the underactuated AUV. Simulation studies are conducted to show the effectiveness and robustness of the controller.

The highly conserved 5' untranslated region as an effective target towards the inhibition of Enterovirus 71 replication by unmodified and appropriate 2'-modified siRNAs.

BACKGROUND: Enterovirus 71 (EV71) is a highly infectious agent that plays an etiological role in hand, foot, and mouth disease. It is associated with severe neurological complications and has caused significant mortalities in recent large-scale outbreaks. Currently, no effective vaccine or specific clinical therapy is available against EV71. METHODS: Unmodified 21 nucleotide small interfering RNAs (siRNAs) and classic 2'-modified (2'-O-methylation or 2'-fluoro modification) siRNAs were designed to target highly conserved 5' untranslated region (UTR) of the EV71 genome and employed as anti-EV71 agents. Real-time TaqMan RT-PCR, western blot analysis and plaque assays were carried out to evaluate specific viral inhibition by the siRNAs. RESULTS: Transfection of rhabdomyosarcoma (RD) cells with siRNAs targeting the EV71 genomic 5' UTR significantly delayed and alleviated the cytopathic effects of EV71 infection, increased cell viability in EV71-infected RD cells. The inhibitory effect on EV71 replication was sequence-specific and dosage-dependent, with significant corresponding decreases in viral RNA, VP1 protein and viral titer. Appropriate 2'-modified siRNAs exhibited similar RNA interference (RNAi) activity with dramatically increased serum stability in comparison with unmodified counterparts. CONCLUSION: Sequences were identified within the highly conserved 5' UTR that can be targeted to effectively inhibit EV71 replication through RNAi strategies. Appropriate 2'-modified siRNAs provide a promising approach to optimizing siRNAs to overcome barriers on RNAi-based antiviral therapies for broader administration.

[Epidemiological analysis on leprosy in China, 2009].

OBJECTIVE: To study the epidemiological characteristics of leprosy and to provide evidence for specific strategies development on leprosy control. METHODS: Descriptive analysis of data from the national leprosy surveillance system was carried out in 2009. RESULTS: A total number of 1597 new cases were detected in 2009 with a case detection rate of 0.120 per 100 000 population. The proportions of children under 15, multibacillary and disability grade 2 were 2.4%, 84.3% and 22.8% respectively. A total number of 148 relapse cases were reported in 2009, among which 69 cases were those relapsed after multi-drug therapy. The existing cases were 6603 by the end of 2009 with a prevalence rate of 0.049 per 10 000 populations, among which 3332 cases were on multi-drug therapy. CONCLUSION: The overall leprosy situation is considered to be at low endemic in China but the distribution is unequal, with pocket areas in Yunnan, Sichuan and Guizhou. In order to reach the target on leprosy elimination, which was considered as a public health and social problem, the input and efforts are needed for many years to come.

[Association between hand-foot-and-mouth disease in Xi'an and enterovirus 71].

OBJECTIVE: To isolate the prevalent strain of enterovirus 71 (EV71) in Xi'an area in 2008, and compare the concordance of viral isolation, reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescent technique in detecting EV71, find the fast and effective method for detection, and analyze the differences between the EV71 strains isolated from Xi'an and Fuyang, Anhui. METHOD: Virus isolation and RT-PCR were carried out on vesicle fluid and throat swab specimens that were collected from the patients with hand-foot-and-mouth disease, RD and HEp-2 cell lines were used for viral isolation. The virus was identified by using immunofluorescence technique. Nucleotide sequencing was performed on positive product of RT-PCR, and compared with EV71 isolated from Fuyang in 2008, then submitted to Genbank. RESULT: Among the 56 samples of throat swab inoculated on RD and HEp-2 cells, the positive rates were 5.4% (3/56) and 1.8% (1/56), respectively. Among the 56 samples of vesicle fluid inoculated on RD and HEp-2 cells, the positive rates were 12.5% ( 7/56 ) and 5.4% (3/56), respectively. Cytopathic effect of RD and HEp-2 cells appeared on days 7 and 10, respectively. The positive rates of RT-PCR on throat swab and vesicle fluid samples were 21.4% (12/56) and 33.9% (19/56), respectively. Cytopathic effect was found in cell culture for 14 cases and immunofluorescence, showed that 9 of them were infected with EV71. The authors obtained the EV71 strain prevalent in Xi'an during 2008. The nucleotide sequence was submitted to the NCBI Genbank and gained the accession number EU812461. CONCLUSION: The EV71 in Xi'an prevalent during 2008 may have a weaker epithelial tropism. Comparison of the EV71 strain isolated from Xi'an with EU703812, EU703813 and EU703814 isolated from Fuyang, Anhui showed that the homology was 97%-98%. RT-PCR is an important method for rapid detection of EV71.

[Preparation, characterization and application of anti-human adenovirus monoclonal antibody with neutralization activity.].

AIM: To prepare, identify and apply anti-human adenoviru(HAdv)neutralization monoclonal antibody(mAb). METHODS: BALB/c mice were immunized with live human adenovirus type3(HAdv-3) strain intranarially. Sp2/0 cells were fused with the spleen cells harvested from BALB/c mice. The chromosomal amounts of the hybridoma cells were analyzed by colchicine. A commercially available mouse mAb isotyping kit was used to identify the isotype of this mAb. Clones secreting specific monoclonal antibody were screened by indirect enzyme linked immunosorbent assay (ELISA), Western blot and indirect immunofluorescent assay. Infected animal model was established, and the protective effect of mAb was studied. RESULTS: The fusion rate was 86%, and the positive rate was 51.4%. One of the hybridoma cell was identified(1A4), the chromosomal amounts of was 98, the subtype mAb type belonged to IgG2a/kappa, and the titer of the mAb secreted by the strain in ascite reached more than 10(-5);. The specificity of the mAb was proved by ELISA , Western blot and indirect immunofluorescent assay. This mAb had protective effect on animal infected by HAdv-3. CONCLUSION: The anti-adenovirus mAb which have neutralization activities was successfully prepared. The mAb recognized the hexon subunit and had protective effect on animal infected by HAdv-3.

Mathematical guide to minimize donor size in full-thickness skin grafting.

BACKGROUND: Full-thickness skin grafting is a common repair option in dermatologic surgery. Generally, a 3:1 ellipse is designed for the donor area. This results in occasional large donor site defects. A new formula to guide donor site design would potentially create smaller donor defects. OBJECTIVE: To design a mathematical formula to facilitate smaller donor incisions. METHODS: A geometric analysis was undertaken to design a practical formula to create smaller defects. This strategy was then used in a case series of 23 patients with large (average 11 cm in diameter) defects [This sentence was corrected after online publication on June 29, 2009: (average 16 x 11 cm) changed to read (average 11 cm in diameter).]. A geometrical analysis was used to design the best way to divide donor grafts to minimize tissue loss. RESULTS: A formula called for the diameter of the primary defect to be multiplied by 3/2 and 2/3 to design a donor ellipse length and width, respectively. The resulting graft was divided into two equal sizes, using a tangential acute angle. The width and the area of the donor were significantly smaller, so the donor site was repaired using a shorter and faster repair. CONCLUSION: Skin graft harvest may be accomplished using a smaller donor graft than previously described using the formula reported here. This will probably reduce surgical morbidity, time, and expense. The authors have indicated no significant interest with commercial supporters.

[Construction and preliminary panning of Fab phage display antibody library against respiratory syncytial virus].

OBJECTIVE: To construct a human phage display antibody library, which will help to develop new drugs and vaccines against respiratory syncytial virus (RSV) and solve many of the issues that have limited the progression and application of murine monoclonal antibodies (McAbs) in the clinic. This can provide a platform for human antibody preparation and diagnosis, prophylaxis and therapy of RSV infection in children. METHODS: Peripheral blood lymphocytes were isolated from 52 children with RSV infection. cDNA was synthesized from the total RNA of lymphocytes. The light and heavy chain Fd (VH-CH1) fragments of immunoglobulin gene were amplified by RT-PCR. The amplified products were cloned into phagemid vector pComb3x and the clone samples were electrotransformed into competent E.coli XL1-Blue. The transformed cells were then infected with M13K07 helper phage to yield recombinant phage antibody of Fabs. The plasmids extracted from amplified E.coli were digested with restriction endonucleases Sac I, Xba I, Spe I and Xho I to monitor the insertion of the light or heavy chain Fd genes. RSV virions were utilized as antigens to screen Fab antibodies. RESULTS: By recombination of light and heavy chain genes, an immune Fab phage display antibody library against RSV containing 2.08x10(7) different clones was constructed, in which 70% clones had light chains and heavy chain Fd genes. The capacity of Fab phage antibody gene library was 1.46x10(7) and the titre of the original Fab antibody library was about 1.06x10(12) pfu/mL. The antibody library gained an enrichment in different degrees after the preliminary panning. CONCLUSIONS: Utilizing the technology of phage display, an immune Fab phage display antibody library against RSV was successfully constructed in this study, which laid a valuable experimental foundation for further study and created favorable conditions for preparing human McAbs. This may also contribute to the improvement in the diagnosis, therapy and prophylaxis of RSV infection in children.

[Fusion expression of human beta defensin 4 in Escherichia coli and preparation of its polyclonal antibody].

AIM: To construct the prokaryotic fusion expression vector of human beta defensin 4 (HBD4), and to express GST-HBD4 fusion protein in Escherichia coli (E.coli) and prepare polyclonal antibody of GST-HBD4. METHODS: The gene encoding mature peptide of HBD4 (mHBD4) was amplified by PCR from cloning vector PMD18-T/HBD4 which contained the full-length HBD4 cDNA and then cloned into prokaryotic expression vector PGEX-4T-2 to construct PGEX-4T-2/mHBD4. GST-HBD4 expression was induced by IPTG. The antiserum was prepared by immunizing rabbit with GST-HBD4.The titer and specificity of the antibody were detected by ELISA and Western blot, respectively. RESULTS: The recombinant expression vector PGEX-4T-2/mHBD4 was successfully constructed. After being induced by IPTG, The fusion protein with relative molecular mass of 32 000 was successfully expressed in E.coli and partly expressed in the soluble form in supernatant. The rabbit antibody against GST-HBD4 was obtained. The ELISA titer of antiserum against GST-HBD4 was about 1:128 000. Western blot analysis showed that the antiserum could bind to the expressed GST-HBD4 specifically. CONCLUSION: The rabbit antibody against GST-HBD4 has been successfully prepared, which lays the foundation for further studying the structure and function of HBD4.

[A long-term evolution on the epidemiological characteristics of leprosy, towards the goal of its elimination in 1949 - 2007 in China].

OBJECTIVE: To understand the epidemiological characteristics of leprosy during the evolution of the disease, towards the goal of elimination for the past 50 years and longer, so as to provide experiences for accelerating eradication of leprosy in China. METHODS: Data were collected from National Surveillance System of Leprosy which was composed annually of all the data from county-based leprosy unit reporting system. All the data were reviewed retrospectively. RESULTS: A total number of 487 900 leprosy patients were reported from 1949 to 2007 in China. The case detection rate reduced from the highest of 5.56/100 000 in 1958 to the lowest of 0.12/100 000 in 2007. Leprosy patients mainly distributed in mountain areas in Yunnan, Guizhou, Sichuan, Guangdong Guangxi, Hunan and Jiangxi provinces with warm and damp climate and underdeveloped economy. After more than 50 years of leprosy control efforts, the case detection rate declined quickly in provinces in the eastern and the southern parts but very slowly in provinces in the western and the southwestern part of China. The ratio of relapsed patients to newly detected ones increased from 1:139 in 1960s' to 1:10 after 1980s', annually. The proportion of child cases among newly detected patients had been 3% - 4% since 1968. In the recent 20 years, the proportion of new patients with positive skin smear gradually increased and the rate of disability grade two reached 20% and more. The average age of new patients upon diagnosis was 45 years old in the east coastal provinces but only 38 years old in the southwest provinces. A new finding was that some new patients detected in the east coastal provinces were immigrants from the southwestern provinces. CONCLUSION: With continuous socio-economic development and active efforts on leprosy control, the prevalence of leprosy gradually declined despite the long evolution period. Some negative events seemed to have influenced the trend of case detection.

[Comparative proteome analysis of human papillomavirus-infected cervical specimens and the difference between the high- and low-risk genotypes of human papillomavirus].

OBJECTIVE: To perform an comparative proteome analysis of human papillomavirus-infected cervical specimens and to investigate different expressions between high- and low-risk genotypes. METHODS: The cervical specimens were divided into two groups (cervical intraepithelial neoplasia group and condyloma acuminatum group) according to their genotypes. Using comparative proteome technology, high-risk human papillomavirus-infected cervical intraepithelial neoplasia, low-risk human papillomavirus-infected condyloma acuminatum, and normal cervical intraepithelial tissue were compared. The differential expression protein spots were identified by mass spectrometry. RESULTS: Totally 26 differential spots were selected and analyzed, and 22 peptide mass fingerprints (PMF) maps were obtained by MALDI-TOF-MS. Eighteen proteins were preliminarily identified after searching the NCBInr database. The function information of these 18 proteins mainly involved cell metabolism, signal transduction, cell secretion, cell cytoskeleton construction, cell proliferation, and apoptosis. CONCLUSION: The proteomic expressions after the cervical infection of high- or low-risk genotype of human papillomavirus are obviously different.

[Effects of Baobaole oral liquid on neuron excitability of feeding center in anorectic rats].

OBJECTIVE: To investigate the effects of Baobaole oral liquid on neuronal excitability in lateral hypothalamic area (LHA) and ventromedial hypothalamic nuclear (VMN) in anorectic rats. METHODS: The anorectic rat model was established by feeding with special prepared forage for a week, and then Baobaole oral liquid, a liquid extract of a compound traditional Chinese medicine for activating spleen, was administered once a day for 3 weeks. Finally, extracellular recording from LHA and VMN neurons in rats were made in order to characterize their responses to gastric vagal nerve stimulation and intravenous injection of glucose in the normal, untreated, and Baobaole-treated groups. RESULTS: There was no statistical difference in response characteristics of LHA neurons to gastric vagal stimulation among 3 groups. The duration of VMN neuron excitation response to gastric vagal nerve stimulation in the untreated group was significantly longer than that of the normal control group (P<0.01), while the required stimulation intensity was significantly decreased (P<0.01). Moreover, among the neurons responding to the gastric vagal stimulation in the untreated group, the number of glycemia-sensitive neurons decreased in LHA and increased in VMN (P<0.01). The gastric vagal stimulation induced neuron responses in LHA and VMN of the Baobaole-treated group were not significantly changed as compared with the normal control group (P<0.01), and neither were the intravenous injection of glucose induced responses. CONCLUSION: Baobaole oral liquid can modulate the sensitivity of LHA and VMN neurons to the peripheral signal and make the coordination between LHA and VMN neurons in order to improve the appetite of anorectic rats.

Syphilis in China: results of a national surveillance programme.

BACKGROUND: After a massive syphilis epidemic in the first half of the 20th century, China was able to eliminate this infection for 20 years (1960-80). However, substantial changes in Chinese society have been followed by a resurgent epidemic of sexually transmitted diseases. Sporadic reports have provided clues to the magnitude of the spread of syphilis, but a national surveillance effort is needed to provide data for planning and intervention. METHODS: We collected and assessed case report data from China's national sexually transmitted disease surveillance system and sentinel site network. FINDINGS: In 1993, the reported total rate of cases of syphilis in China was 0.2 cases per 100,000, whereas primary and secondary syphilis alone represented 5.7 cases per 100,000 persons in 2005. The rate of congenital syphilis increased greatly with an average yearly rise of 71.9%, from 0.01 cases per 100,000 livebirths in 1991 to 19.68 cases per 100 000 livebirths in 2005. INTERPRETATION: The results suggest that a range of unique biological and social forces are driving the spread of syphilis in China. A national campaign for detection and treatment of syphilis, and a credible prevention strategy, are urgently needed.

Prevalence of sexually transmitted infections among long-distance truck drivers in Tongling, China.

Little is known about sexually transmitted infections (STIs), including HIV, among truck drivers in China. A cross-sectional study was conducted among truck drivers in Tongling of Anhui Province. A total of 550 truck drivers were interviewed with a structured questionnaire, and blood samples were collected and tested for HIV, syphilis, and herpes simplex virus 2 (HSV-2), and urine specimens for Neisseria gonorrhoeae and Chlamydia trachomatis. Prevalence was 10.6% for C. trachomatis and 8.1% for N. gonorrhoeae. Antibodies for syphilis were found in 0.7% and for HSV-2 in 4.4%, and none was positive for HIV. About 92 (17.4%) truck drivers had at least one STI. There was no statistically significant association between sociodemographic, occupation or behavioural variables and the presence of a positive test for any STI. Our study suggests a high prevalence of STIs, particularly bacterial infections, among the truck drivers, indicating the need for health education, behavioural change interventions and STI care services in this population.

[Effect of er'bao granule on integration of ingestion behavior-related information by neurons in lateral hypothalamic area of anorexia rats].

OBJECTIVE: To confirm the effect of Er'bao granule (EBG) on the sensitivity to peripheral afferent signal of neurons in lateral hypothalamic area (LHA) to illustrate the central mechanism of EBG in promoting ingestion behavior. METHODS: The anorexia rat model was established by feeding special prepared forage for one week, and all the model rats were administrated with EBG by gavage for 3 weeks. The spontaneous discharge of LHA neurons was recorded using electro-physiological extracellular recording method, and its response to electrical stimulus on gastric vagus nerve and intravenous injection of glucose were observed and compared among the normal, model and treated groups. RESULTS: As compared with the normal group, among the LHA neurons responding to afferent gastric vagal impulse, the proportion of glycemia-sensitive neurons in the model group was significantly decreased (P <0.01), but insignificant difference was shown in comparison between the treated group and the normal group. CONCLUSION: EBG play a role in regulating the sensitivity of LHA neurons to peripheral afferent signal and thus to influence the multi-afferent information integration of ingestion central neurons.

[Treatment of respiratory syncytial virus by intravenous gamma-globulin].

AIM: To explore in vitro and in vivo the effect of the intravenous gamma-globulin (IVgammaG) on the respiratory syncytial virus (RSV). METHODS: (1) The microdose cytopathogenic inhibition assay (MCIA) was used to observe the effect of different concentrations of IVgammaG on RSV replication. (2) 40 BALB/c mice were infected with RSV and then randomly divided into four groups: namely, the IVgammaG treatment group, the ribavirin treatment group, the Palivizumab treatment group and the normal saline group (control group). Half of the mice in each group were killed at the fifth day and the seventh day after treatment, respectively, to isolate the virus and perform pathological examination of the lung tissue. RESULTS: (1) IVgammaG inhibited RSV replication in vitro. The treatment index (TI) of IVgammaG was 275, which was about 7 times of TI of ribavirin and one third of Palivizumab. (2) The pathological score of the lung tissue in the IVgammaG group was lower than that of control group (P<0.01), but higher than that of Palivizumab group (P<0.05). CONCLUSION: The IVgammaG has an anti-RSV effect both in vivo and in vitro, but its effect is lower than that of Palivizumab.

[Long-term results after the correction of the paralytic ectropion caused with leprosy in 115 eyes].

OBJECTIVE: To analyze the long-term results after the correction of the paralytic ectropion in leprosy. METHODS: Seventy-four patients with 115 paralytic ectropion eyes after leprosy were treated with the surgical procedures included medial canthoplasty, medial canthal tendon plication, lateral tarsal strip, medial canthal resection, lateral canthoplasty, and lid shortening. The results were evaluated with the follow-ups from 2 to 4 years. RESULTS: The eye-redness was reduced from 93 to 40 while the epiphora from 107 eyes (24 mild, 36 moderate and 47 severe) to 90 (40 mild, 32 moderate and 18 severe). The mean lid gap in mild eye closure was reduced from 6.8 mm to 5.3 mm and the cornea lesion was reduced from 53 to 36. The results were excellent in 18 eyes (15.7%), good in 45 eyes (39.1%), fair in 41 eyes (35.7%) and poor in 11 eyes (9.6%). However, the mean visual acuity remained same pre- and postoperatively. CONCLUSIONS: Surgical correction of ectropion is helpful for cornea protection and could improve the signs and symptoms of the eyes such as epiphora and red [abstract truncated].

[Genetic diversity of human Parvovirus B19 VP1 unique region].

OBJECTIVE: Human Parvovirus B19 (HPV B19) is a small (23 nm), non-enveloped DNA virus found in 1974. It has been proved that HPV B19 is associated with a variety of childhood diseases, such as erythema infectious, transient aplastic crisis, aplastic anemia, idiopathic thrombocytopenic purpura and arthropathy, etc. There have been no any effective vaccines to prevent HPV B19 infection so far. The HPV B19 genome is composed of 5.6 kb single strand DNA. This genome encodes a nonstructural protein NS1, two structural proteins VP1 and VP2. Most neutralizing linear epitopes of HPV B19 cluster in the VP1 unique and VP1-VP2 junction regions. Only proteins encoded by genes of the VP1 unique and VP1-VP2 junction regions can stimulate bodies to produce protective antibodies. Aim of the present study was to get the VP1 unique region gene of HPV B19 and to analyze the genetic diversity so as to further study its function and application. METHODS: The VP1 unique region gene of HPV B19 was amplified from the serum of a child with idiopathic thrombocytopenic purpura by PCR. The purified PCR product was cloned into pGEM-T easy vector and transfected into the host strain E. coli (DH5 alpha). Positive clones were chosen and then the target gene was sequenced. RESULTS: The target gene sequence of HPV B19 VP1 unique region was amplified and cloned successfully. It had 705 nucleotides. Compared with the relevant sequences published in Genbank, the sequencing results were revealed with two nucleotides changes in the HPV B19 VP1 unique region, but their coding amino acid were not changed. CONCLUSION: It is suggested that genetic diversity exists in the VP1 unique region of HPV B19. Construction of the recombinant plasmid of HPV B19 VP1 unique region gene might benefit to further study.