Projected COVID-19 epidemic in the United States in the context of the effectiveness of a potential vaccine and implications for social distancing and face mask use

BackgroundMultiple candidates of COVID-19 vaccines have entered Phase III clinical trials in the United States (US). There is growing optimism that social distancing restrictions and face mask requirements could be eased with widespread vaccine adoption soon. MethodsWe developed a dynamic compartmental model of COVID-19 transmission for the four most severely affected states (New York, Texas, Florida, and California). We evaluated the vaccine effectiveness and coverage required to suppress the COVID-19 epidemic in scenarios when social contact was to return to pre-pandemic levels and face mask use was reduced. Daily and cumulative COVID-19 infection and death cases were obtained from the Johns Hopkins University Coronavirus resource center and used for model calibration. ResultsWithout a vaccine, the spread of COVID-19 could be suppressed in these states by maintaining strict social distancing measures and face mask use levels. But relaxing social distancing restrictions to the pre-pandemic level without changing the current face mask use would lead to a new COVID-19 outbreak, resulting in 0.8-4 million infections and 15,000-240,000 deaths across these four states over the next 12 months. In this scenario, introducing a vaccine would partially offset this negative impact even if the vaccine effectiveness and coverage are relatively low. However, if face mask use is reduced by 50%, a vaccine that is only 50% effective (weak vaccine) would require coverage of 55-94% to suppress the epidemic in these states. A vaccine that is 80% effective (moderate vaccine) would only require 32-57% coverage to suppress the epidemic. In contrast, if face mask usage stops completely, a weak vaccine would not suppress the epidemic, and further major outbreaks would occur. A moderate vaccine with coverage of 48-78% or a strong vaccine (100% effective) with coverage of 33-58% would be required to suppress the epidemic. Delaying vaccination rollout for 1-2 months would not substantially alter the epidemic trend if the current interventions are maintained. ConclusionsThe degree to which the US population can relax social distancing restrictions and face mask use will depend greatly on the effectiveness and coverage of a potential COVID-19 vaccine if future epidemics are to be prevented. Only a highly effective vaccine will enable the US population to return to life as it was before the pandemic.

Effects of New York's Executive Order on Face Mask Use on COVID-19 Infections and Mortality: A Modeling Study

BackgroundNew York City (NYC) was the epicenter of the COVID-19 pandemic in the United States. On April 17, 2020, the State of New York implemented an Executive Order that requires all people in New York to wear a face mask or covering in public settings where social distancing cannot be maintained. It is unclear how this Executive Order has affected the spread of COVID-19 in NYC. MethodsA dynamic compartmental model of COVID-19 transmission among NYC residents was developed to assess the effect of the Executive Order on face mask use on infections and deaths due to COVID-19 in NYC. Data on daily and cumulative COVID-19 infections and deaths were obtained from the NYC Department of Health and Mental Hygiene. ResultsThe Executive Order on face mask use is estimated to avert 99,517 (95% CIs: 72,723-126,312) COVID-19 infections and 7,978 (5,692-10,265) deaths in NYC. If the Executive Order was implemented one week earlier (on April 10), the averted infections and deaths would be 111,475 (81,593-141,356) and 9,017 (6,446-11,589), respectively. If the Executive Order was implemented two weeks earlier (on April 3 when the Centers for Disease Control and Prevention recommended face mask use), the averted infections and deaths would be 128,598 (94,373-162,824) and 10,515 (7,540-13,489), respectively. ConclusionsNew Yorks Executive Order on face mask use is projected to have significantly reduced the spread of COVID-19 in NYC. Implementing the Executive Order at an earlier date would avert even more COVID-19 infections and deaths.

Effect of Shaoyaotang on Expressions of AP-1 and TNF-α in Colon of Rats with Hygrothermal Ulcerative Colitis / 中国实验方剂学杂志

Objective: To observe the effect of Shaoyaotang on mRNA and protein expressions of colon tissue activated protein-1 (AP-1) and tumor necrosis factor-α (TNF-α) of hot and humid-type intrinsic ulcerative colitis (UC) model in rats, in order to explore the mechanism of action of herbaceous peony decoction in the treatment of UC. Method: Totally 60 Wistar rats were randomly divided into blank group, model group, SASP group, and low, medium and high-dose Shaoyaotang groups. The damp-heat intrinsic UC rat model was replicated based on integrated disease and syndrome, namely, high-fat and high-sugar spicy food and immune complex method combined with 2,4,6-trinitrobenzene sulfolnic acid (TNBS) and ethanol complex method. After the successful modeling, low, medium and high-dose Shaoyaotang (6, 12, 24 g·kg-1) was given by gavage, and 1 g·kg-1 dose of salazol sulfadiazine was given to by gavage. The blank group was given constant volume normal saline for 21 d. Real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was used to detect mRNA expressions of AP-1 and TNF-α in colon tissues, and Western blot was used to detect protein expressions of AP-1 and TNF-α in colon tissues. Result: Compared with the blank group, relative mRNA and protein expressions of AP-1, TNF-α in the model group were significantly increased (Pα in the treatment groups were significantly decreased (PConclusion: Shaoyaotang can inhibit the expression of TNF-α and stimulate AP-1 protein expression in rats with damp-heat UC.

Influence of PCI and thrombolytic therapy on therapeutic effect and reperfusion of AMI patients / 心血管康复医学杂志

Objective:To compare influence of percutaneous coronary intervention(PCI)and thrombolytic therapy on therapeutic effect and reperfusion in patients with acute myocardial infarction(AMI).Methods:A total of 118 AMI patients treated in our hospital from Jan 2013 to Dec 2016 were enrolled.They were divided into thrombolysis group (n=38)and PCI group(n=80).Therapeutic effect,cardiac function and reperfusion indexes were compared be-tween two groups.Results:Compared with thrombolysis group,there was significant rise in total effective rate (84.21% vs.97.50%),and significant reduction in total incidence rate of adverse events(18.42% vs.2.50%)in PCI group,P< 0.01 both.Compared with before treatment,there were significant reductions in left ventricular end-systolic dimension(LVESd)of two groups and left ventricular end-diastolic dimension(LVEDd)of PCI group, and significant rise in creatine kinase isoenzyme-MB(CK-MB)level of two groups after treatment,P=0.001 all. Compared with thrombolysis group after treatment,there were significant reductions in LVEDd[(32.45 ± 2.21)mm vs.(29.86 ± 3.96)mm]and LVESd[(49.85 ± 1.32)mm vs.(46.86 ± 2.34)mm],and significant rise in CK-MB level[(389.74 ± 2.74)ng/ml vs.(706.96 ± 3.78)ng/ml]in PCI group,P=0.001 all.Conclusion:Compared with thrombolytic therapy,PCI possesses more significant therapeutic effect on AMI.It can more significantly im-prove patient′s cardiac function,and rise CK-MB level,which has better clinical value.

Predictive value of miRNA-29a and miRNA-10a-5p for 28-day mortality in patients with sepsis-induced acute kidney injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of miR-29a and miR-10a-5p in predicting 28-day mortality in patients with sepsis-induced acute kidney injury.</p><p><b>METHODS</b>Seventy-four patients with sepsis-induced acute kidney injury (AKI) and 41 patients with sepsis but without AKI (control) were examined for serum levels of miR-29a and miR-10a-5p using RT-PCR. The patients were followed up for 28 days to record their survival. Pearson correlation analysis was used to test the correlations of miR-29a and miR-10a-5p with serum creatinine (Scr), cystatin C (Cys-C), and KIM-1 in patients with AKI. Multivariate logistic regression analysis was used to analyze the correlations of miR-29a, miR-10a-5p, Scr, Cys-C, KIM-1 and other risk factors with the 28-day mortality in patients with sepsis. The predictive value of these indicators for evaluating the prognosis of patients with sepsis was analyzed using ROC curve, and miR-29a combined with miR-10a-5p was assessed for their value in predicting the prognosis of the patients.</p><p><b>RESULT</b>During the follow-up for 28 days, 21 of the 74 (35.53%) AKI patients died. Compared with the survivors, the patients died within 28 days showed significantly increased serum levels of Scr , Cys-C, KIM-1, miR-29a, and miR-10a-5p (P<0.05). Pearson correlation analysis showed that miR-29a and miR-10a-5p were positively correlated with serum Scr, Cys-C, and KIM-1 levels; multivariate regression analysis identified miR-29a and miR-10a-5p as the independent risk factors for mortality in the septic patients. The ROC curve analysis showed that the area under the curve (AUC) of miR-29a and miR-10a-5p was 0.82 (95%CI: 0.71-0.89) and 0.75 (95%CI: 0.64-0.85), and that of Scr, Cys-C and KIM-1 was 0.72 (95%CI: 0.66-0.86) , 0.71 (95% CI: 0.63-0.84) and 0.81 (95% CI: 0.72-0.81), respectively. The AUC of miR-29a combined with miR-10a-5p was significantly greater than that of miR-29a, miR-10a-5p, Scr, Cys-C and KIM-1 alone (P<0.05).</p><p><b>CONCLUSION</b>miR-29a and miR-10a-5p have good predictive value in assessing the 28-day mortality of patients with sepsis.</p>

Genome-wide miRNAs expression profiles of Schistosoma japonicum schistosomula in response to artesunate.

AIM: miRNAs play a significant role in pharmacogenomics and are likely to be important in the molecular mechanism of atesunate (ART) effects on Schistosoma japonicum. METHODS: We sequenced the RNAs using an Illumina (Solexa) DNA sequencer and compared the relative expression levels of the miRNAs in 10-day-old schistosomula from ART and the parallel control group. RESULTS: We characterized 95 known miRNAs from S. japonicum schistosomula individuals, including 38 novel miRNA families. Among the detectable 134 miRNAs differentially expressed (>2.0-fold change, p < 0.01) after ART treatment in schistosomula, a total of seven known or novel 3p- or 5p- derived S. japonicum miRNAs were characterized. We propose that sja-miR-125b may regulate the expression of ART metabolizing enzymes, glutathione synthetase or heme-binding protein 2 to help S. japonicum resists or adapts to drug stress and also ART may significantly inhibit sexual maturation of female worms mediated by mir-71b/2 miRNA cluster. CONCLUSION: This was the first comprehensive miRNAs expression profile analysis of S. japonicum in response to ART, and provides an overview of the complex network of the mechanism of action of ART on S. japonicum.

Inhibition of autophagy induced by PTEN loss promotes intrinsic breast cancer resistance to trastuzumab therapy.

This study aims to explore the effects of the phosphatase and tension homolog (PTEN) expression level on autophagic status and on the resistance of breast cancer to trastuzumab treatment. PTEN and LC3I/II were knocked down with shRNA expression vectors, which were transfected into estrogen receptor (ER)-positive breast cancer cell lines. After trastuzumab treatment, the changes in the autophagy signal transduction pathways and autophagic proteins (LC3I/II, p62, LAMP, and cathepsin B) in these stably transfected cells were detected using western blot. The cells were also orthotopically implanted into nude mice to explore the influence of PTEN knockdown on tumor size, cell viability, and autophagic proteins after trastuzumab treatment. Similar determinations were performed using the LC3I/II overexpressed shPTEN breast cancer cells (LC3I/II-shPTEN). Downregulation of PTEN and autophagic proteins LC3-I and LC3-II was observed in resistant human breast cancer samples. Knockdown of PTEN and PTEN+ LC3I/II with shRNA in breast cancer cells resulted in increased resistance to trastuzumab. Consistently, trastuzumab treatment could not effectively reduce tumor size. Significant decreases in the levels of autophagic proteins LC3I/II, LAMP, p62, cathepsin B, and PI3K-Akt-mTOR and the signaling pathway protein Akt were found in PTEN knockdown cells, compared to the PTEN normal group, after trastuzumab administration, both in vitro and in vivo. However, these findings were reversed with the LC3I/II-shPTEN treatment. Therefore, the loss of PTEN may promote the development of primary resistance to trastuzumab in breast cancer via autophagy defects.

Randomized Controlled Trial on Siege Scheme of Traditional Chinese Medicine to Treat Excess Syndrome of Stroke with Bowel and Visceral Strike / 中国中医药信息杂志

Objective To evaluate the efficacy of siege scheme of TCM for acute cerebral infarction bowel and visceral strike (block pattern). Methods Totally 110 patients were randomly divided into TCM siege scheme group (55 cases) and control group (55 cases) by randomized parallel controlled study with foresight and multicenter. The control group was treated with the standardized treatment, and TCM siege scheme group was treated with TCM siege scheme, including mild hypothermia TCM pillow therapy, TCM rectal enema, and other multiple treatments based on the standardized treatment. The Glasgow Coma Scale (GCS), the time of pulling out urine tube and nasal feeding tube, and the number of tracheotomy caused by illness changes of the two groups were compared. Results The baseline data of two groups have good comparability (P>0.05). On 10, 15 d of treatment, the number of lucid people in the TCM siege scheme group was significantly more than that in the control group (P<0.05). Compared with the control group, treatment group had less number of tracheotomy, and shorter time of success pulling out urine tube and nasogastric feeding tube (P<0.05). Conclusion TCM siege scheme can improve the consciousness of ischemic stroke in patients with acute cerebral infarction bowel and visceral strike, reduce complications, shows shorter successful pull urine tube and nasogastric feeding, and provides guarantee conditions for further rehabilitation treatment.

Survey of Hepatitis B infection and vaccination status among drug users in Xi'an / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore seroepidemiological status and vaccine coverage of hepatitis B among drug users in Xi'an.</p><p><b>METHODS</b>545 drug users in the Xi'an Compulsory Detoxification Center were asked to answer questionnaire and provide blood sample (3-5 ml) for test of HBsAg, anti-HBc and anti-HBs from March to June 2013. Totally, 545 subjects were surveyed and tested. All of them effectively completed the survey.</p><p><b>RESULTS</b>The positive rates of HBsAg, anti-HBc and anti-HBs were 29.4% (160/545), 60.0% (327/545) and 56.1% (306/545), respectively. Eighty five subjects (15.6%) were negative for all of the three markers. The prevalence of HBsAg and anti-HBc among injection drug users were 40.0% (94/235) and 65.6% (154/235), which was significantly higher than non- injection drug users' (21.6% (52/241), 58.5% (141/241)) and mixed non-injection and injection drug users ((20.3% (14/69), 46.4% (32/69)) (χ(2) = 23.518 and 9.017, respectively, P < 0.05) . The HBsAg positive rate (30.6% (153/500)) of subjects with more than once per day of drug using within one year was significantly higher than those who used drugs for 2-3 times per week (15.6% (7/45)) (χ(2) = 4.51, P < 0.05). Only 11.7% (64/545) of drug users had a clear history of hepatitis B vaccination. The vaccination rate of subjects (3.5% (5/141)) with primary education or below was significantly lower than those with high school (16.3% (45/276)) (χ(2) = 26.61, P < 0.05). The vaccination rate of subjects (7.8% (12/153)) over 45 years old was significantly lower than that of subjects below 30 years old (15.9% (21/132)) and 30-44 years old (11.9% (31/260)) (χ(2) = 30.36, P < 0.05). The vaccinees had a significantly higher positive rate of anti-HBs (73.4% (47/64)) than those who without vaccination (53.8% (259/481)) (χ(2) = 8.81, P = 0.003), but the positive rates of HBsAg (16.7% (11/64)) were lower than those who without vaccination (31.0% (149/481)) (χ(2) = 23.52 and 9.02, respectively;P > 0.05).</p><p><b>CONCLUSION</b>The HBV infection status among drug users in Xi'an was in serious condition, while a low vaccination rate was also discovered among them.</p>

Lack of association of common polymorphisms in MUC1 gene with H. pylori infection and non-cardia gastric cancer risk in a Chinese population.

Several lines of evidence support the notion that MUC1 is often aberrantly expressed in gastric cancer, and it is a ligand for Helicobacter pylori. Genetic variation in MUC1 gene may confer susceptibility to H. pylori infection and gastric cancer. We assessed the association of common polymorphisms in MUC1 gene with H. pylori infection and non-cardia gastric cancer using an LD-based tag SNP approach in north-western Chinese Han population. A total of four SNPs were successfully genotyped among 288 patients with non-cardia gastric cancer and 281 age- and sex-matched controls. None of the tested SNPs was associated with H. pylori infection. SNP rs9426886 was associated with a decreased risk of non-cardia gastric cancer, but lost significance after adjustment for multiple testing. Overall, our data indicated that common genetic variations in MUC1 gene might not make a major contribution to the risk of H. pylori infection and non-cardia gastric cancer in our studied population.

[Responses of plant functional traits and soil factors to slope aspect in alpine meadow of South Gansu, Northwest China].

This paper studied the plant functional traits, soil factors, and their relationships at different slope aspects in the alpine meadow of South Gansu. On the sunny slope, grasses were the dominant functional groups; while on the shady slope, forbs and shrubs dominated. The plant community biomass was significantly higher on shady slope than on sunny slope, while the leaf N/P ratio was in adverse. The leaf phosphorus content, specific leaf area, and plant average height at different slope aspects were in the order of shady slope > partial shady slope > sunny slope, whereas the leaf nitrogen content on different slopes had less difference. The survival strategies of the vegetations on sunny and shady slopes had great changes, reflecting in the differences in the plant leaf traits and dominant functional groups. Soil temperature was in the order of sunny slope > partial shady slope > shady slope, while soil water content was in the order of shady slope > partial shady slope > sunny slope. Soil total phosphorus content increased from the sunny slope to the shady slope, while the other soil nutrients contents showed the sequence of shady slope > sunny slope > partial shady slope. The specific leaf area and plant average height were significantly positively correlated to the soil organic carbon, total phosphorous, and water contents, and significantly negatively correlated to soil pH. Soil water content and soil pH co-affected the distribution patterns of plant functional traits and soil nutrients at different slope aspects of alpine meadow.

Development of a rapid dipstick with latex immunochromatographic assay (DLIA) for diagnosis of schistosomiasis japonica.

BACKGROUND: Schistosomiasis japonica (schistosomiasis) is a zoonosis that can seriously affect human health. At present, the immunodiagnostic assays for schistosomiasis detection are time-consuming and require well-trained personnel and special instruments, which can limit their use in the field. Thus, there is a pressing need for a simple and rapid immunoassay to screen patients on a large scale. In this study, we developed a novel rapid dipstick with latex immunochromatographic assay (DLIA) to detect anti-Schisaosoma japonicum antibodies in human serum. RESULTS: Using latex microspheres as a color probe, DLIA was established to test standard positive and negative sera, in comparison with the classical enzyme-linked immunosorbent assay (ELISA). The sensitivity and specificity of DLIA were 95.10% (97/102) and 94.91% (261/275), respectively. The cross-reaction rates with clonorchiosis, intestinal nematodes, Angiostrongylus cantonensis and paragonimiasis were 0, 0, 0 and 42.11% respectively. All the results showed no significant difference to the ELISA. In field tests, 333 human serum samples from an endemic area were tested with DLIA, and compared with ELISA and Kato-Katz method. There was no significant difference between DLIA and ELISA on positive and negative rates of detection; however, significant differences existed between DLIA and Kato-Katz method, and between ELISA and Kato-Katz method. The kappa value between DLIA and ELISA was 0.90. CONCLUSIONS: This is the first study in which DLIA was used to detect anti-Schistosoma japonicum antibody. The results show that DLIA is a simple, rapid, convenient, sensitive and specific assay for the diagnosis of schistosomiasis and is therefore very suitable for large-scale field applications and clinical detection.

[A study of double antigen sandwich colloidal gold immunochromatography rapid detection for Mycobacterium tuberculosis antibody].

OBJECTIVE: To establish a simple, fast and accurate double antigen colloidal gold immunochromatographic technique for detecting Mycobacterium tuberculosis antibody from tuberculosis patients. METHODS: The fusion protein ESAT-6-16-38 was constructed by using gene cloning technique for the 6, 16 and 38 kDa early secreted antigenic target from Mycobacterium tuberculosis. The ESAT-6-16-38 fusion protein was marked to colloidal gold to establish the double antigen colloidal gold immunochromatographic assay. Serum samples from 163 patients with tuberculosis, including 57 sputum-positive cases, 64 sputum-negative cases, and 42 cases with extrapulmonary tuberculosis, were collected during 2007 and 2009 from the Disease Prevention and Control Center of Deqing County. In addition, 573 controls (224 healthy volunteers, 217 patients with acute pneumonia and bronchitis, 132 patients with paragonimiasis) were recruited for comparison. Mycobacterium tuberculosis specific antibodies were detected by using immunochromatographic and protein chip technique. Detection rate was compared with Chi-square test. RESULTS: Among the 163 tuberculosis patients, the positive rates of immunochromatographic detection and protein chip were 73.0% (120/163) and 72.4% (118/163) respectively; the difference was not statistically significant (χ()2 = 0.062, P > 0.05). Among the 573 controls, the negative rates of immunochromatographic detection and protein chip were 93.9% (538/573) and 92.0% (527/573) respectively; the difference was not statistically significant (χ()2 = 0.635, P > 0.05). There was no cross reaction in the paragonimiasis patients. The positive rate of the immunochromatographic assay was as high as 87.7% (50/57) in the sputum-positive patients. CONCLUSIONS: The double antigen immunochromatographic technique is an easy to operate, rapid, highly sensitive, specific, and reproducible method for the detection of Mycobacterium tuberculosis antibodies.

[Establishment and application of rapid dipstick of latex immunochromatographic assay for the diagnosis of schistosomiasis].

OBJECTIVE: To establish a simple and fast diagnostic assay for schistosomiasis. METHODS: Based on the immunochromatographic technique and the principle of indirect assay of ELISA, using soluble egg antigen (SEA) of Schistosoma japonicum and mouse anti-human monoclonal antibody labelled with red latex as color developing agents, a latex immunochromatographic assay (DLIA) was developed. Serum samples from 69 schistosomiasis patients were detected by DLIA. Tested were also 264 sera from healthy people, 15 sera from clonorchiasis patients, 8 sera from patients with angiostrongyliasis cantonensis, 11 sera from patients with intestinal nematode infection and 19 sera from paragonimiasis patients. ELISA was used as a parallel control. RESULTS: The sensitivity for detecting schistosomiasis antibodies with DLIA and ELISA was 94.2% (65/69) and 95.7% (66/69), respectively (chi2=0.15, P>0.05). The specificity in examining healthy persons was 97.4% (257/264) and 94.7% (250/264), respectively (chi2=2.43, P>0.05). No cross reaction was found with the sera of clonorchiasis, intestinal nematode infection and angiostrongyliasis. The cross reaction rate with paragonimiasis of the two assays was 42.1% (8/19) and 47.4% (9/19), respectively (chi2=0.11, P>0.05). CONCLUSION: DLIA is a simple, fast, sensitive and specific assay for the diagnosis of schistosomiasis.

Efficacy and safety assessment of neoadjuvant paclitaxel and trastuzumab in Chinese women with Her-2 positive operable breast cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To assess the efficacy and safety of neoadjuvant 3-weekly paclitaxel plus trastuzumab (TH) in Chinese women with Her-2 overexpressing operable breast cancer.</p><p><b>METHODS</b>This is a single center open-label phase II clinical trial. The included patients underwent 4 cycles of neoadjuvant 3-weekly TH before surgery. The primary endpoint was pathologic complete response rate (pCR rate) and the secondary endpoint was overall response rate (OR rate). Patients were also stratified according to hormone receptor status, and pCR rate and OR rate were compared between subgroups. Adverse events were graded according to CTCAE v3.0.</p><p><b>RESULTS</b>There were 40 eligible patients entering this study with median age of 49 years. All patients completed 4 cycles of neoadjuvant treatment. pCR rate was 52.5% and OR rate was 87.5%. The differences of pCR and OR rates between subgroups were of no statistical significance. No cardiac toxicity event severer than grade 2 was recorded.</p><p><b>CONCLUSION</b>3-weekly TH regimen has satisfactory pCR rate and OR rate in Chinese patients with Her-2 overexpressing operable breast cancer and reliable safety.</p>

Evolutionary dynamics of prey-predator systems with Holling type II.

This paper considers the coevolution of phenotypes in a community comprising the populations of predators and prey. The evolutionary dynamics is constructed from a stochastic process of mutation and selection. We investigate the ecological and evolutionary conditions that allow for continuously stable strategy and evolutionary branching. It is shown that branching in the prey can induce secondary branching in the predators. Furthermore, it is shown that the evolutionary dynamics admits a stable limit cycle. The evolutionary cycle is a likely outcome of the process, which requires higher evolutionary speed of prey than of predators. It is also found that different evolutionary rates and conversion efficiencies can influence the lengths of evolutionary cycles.

[Observation on the change of anti-S. japonicum antibody level in population migrated from outside embankment to new town].

OBJECTIVE: To detect the change of the anti-S. japonicum antibody level after people migrated from outside embankment to newly established town. METHODS: Three pilot spots were established for the investigation: one spot that both inhabitancy and cultivation disuse (A), one spot that only inhabitancy disuse but farming continued (B) and the third one served as control (C). DIGFA and ELISA were used to detect the antibody level in the populations from 2002 to 2005. RESULTS: The positive rate of anti-S. japonicum antibody declined significantly from 6.63% to 3.52% by DIGFA and from 7.26% to 3.71% by ELISA at spot A (chi2=5.2625, P<0.05; chi2=6.3296, P<0.05, respectively). There was no significant difference on the positive rate of antibody in spots B and C. The average A450 value of ELISA in the three spots was statistically analyzed by One-Way ANOVA. It was only in spot B that the average A450 value declined from 0.182 in 2003 to 0.147 in 2005 (P<0.01). CONCLUSION: The anti-S. japonicum antibody level in human population has decreased at certain degree after they migrated from outside embankment to new town.

Recombinant tegumental protein Shistosoma japonicum very lowdensity lipoprotein binding protein as a vaccine candidate against Schistosoma japonicum.

A polyhistidine-tagged recombinant tegumental protein Schistosoma japonicum very lowdensity lipoprotein binding protein (SVLBP) from adult Schistosoma japonicum was expressed in Escherichia coli. The affinity purified rSVLBP was used to vaccinate mice. The worm numbers and egg deposition recovered from the livers and veins of the immunized mice were 33.5% and 47.6% less than that from control mice, respectively (p<0.05). There was also a marked increase in the antibody response in vaccinated mice: the titer of IgG1 and IgG2a, IgG2b in the vaccinated group was significantly higher than that in the controls (>1:6,400 in total IgG). In a comparison of the reactivity of sera from healthy individuals and patients with rSVLBP, recognition patterns against this parasite tegumental antigen varied among different groups of the individuals. Notably, the average titres of anti-rSVLBP antibody in sera from faecal egg-negative individuals was significantly higher than that in sera from the faecal egg-positives, which may be reflect SVLBP-specific protection. These results suggested that the parasite tegumental protein SVLBP was a promising candidate for further investigation as a vaccine antigen for use against Asian schistosomiasis.

Recombinant tegumental protein Shistosoma japonicum very lowdensity lipoprotein binding protein as a vaccine candidate against Schistosoma japonicum

A polyhistidine-tagged recombinant tegumental protein Schistosoma japonicum very lowdensity lipoprotein binding protein (SVLBP) from adult Schistosoma japonicum was expressed in Escherichia coli. The affinity purified rSVLBP was used to vaccinate mice. The worm numbers and egg deposition recovered from the livers and veins of the immunized mice were 33.5 percent and 47.6 percent less than that from control mice, respectively (p<0.05). There was also a marked increase in the antibody response in vaccinated mice: the titer of IgG1 and IgG2a, IgG2b in the vaccinated group was significantly higher than that in the controls (>1:6,400 in total IgG). In a comparison of the reactivity of sera from healthy individuals and patients with rSVLBP, recognition patterns against this parasite tegumental antigen varied among different groups of the individuals. Notably, the average titres of anti-rSVLBP antibody in sera from faecal egg-negative individuals was significantly higher than that in sera from the faecal egg-positives, which may be reflect SVLBP-specific protection. These results suggested that the parasite tegumental protein SVLBP was a promising candidate for further investigation as a vaccine antigen for use against Asian schistosomiasis.