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1.
Evol Bioinform Online ; 16: 1176934320970572, 2020.
Article in English | MEDLINE | ID: mdl-33328721

ABSTRACT

Microbial community is ubiquitous in nature, which has a great impact on the living environment and human health. All these effects of microbial communities on the environment and their hosts are often referred to as the functions of these communities, which depend largely on the composition of the communities. The study of microbial higher-order module can help us understand the dynamic development and evolution process of microbial community and explore community function. Considering that traditional clustering methods depend on the number of clusters or the influence of data that does not belong to any cluster, this paper proposes a hypergraph clustering algorithm based on game theory to mine the microbial high-order interaction module (HCGI), and the hypergraph clustering problem naturally turns into a clustering game problem, the partition of network modules is transformed into finding the critical point of evolutionary stability strategy (ESS). The experimental results show HCGI does not depend on the number of classes, and can get more conservative and better quality microbial clustering module, which provides reference for researchers and saves time and cost. The source code of HCGI in this paper can be downloaded from https://github.com/ylm0505/HCGI.

2.
BMC Bioinformatics ; 19(Suppl 20): 505, 2018 Dec 21.
Article in English | MEDLINE | ID: mdl-30577738

ABSTRACT

BACKGROUND: The traditional methods of visualizing high-dimensional data objects in low-dimensional metric spaces are subject to the basic limitations of metric space. These limitations result in multidimensional scaling that fails to faithfully represent non-metric similarity data. RESULTS: Multiple maps t-SNE (mm-tSNE) has drawn much attention due to the construction of multiple mappings in low-dimensional space to visualize the non-metric pairwise similarity to eliminate the limitations of a single metric map. mm-tSNE regularization combines the intrinsic geometry between data points in a high-dimensional space. The weight of data points on each map is used as the regularization parameter of the manifold, so the weights of similar data points on the same map are also as close as possible. However, these methods use standard momentum methods to calculate parameters of gradient at each iteration, which may lead to erroneous gradient search directions so that the target loss function fails to achieve a better local minimum. In this article, we use a Nesterov momentum method to learn the target loss function and correct each gradient update by looking back at the previous gradient in the candidate search direction. By using indirect second-order information, the algorithm obtains faster convergence than the original algorithm. To further evaluate our approach from a comparative perspective, we conducted experiments on several datasets including social network data, phenotype similarity data, and microbiomic data. CONCLUSIONS: The experimental results show that the proposed method achieves better results than several versions of mm-tSNE based on three evaluation indicators including the neighborhood preservation ratio (NPR), error rate and time complexity.


Subject(s)
Gene Expression Regulation , Genetic Diseases, Inborn/genetics , Microbiota/genetics , Nonlinear Dynamics , Algorithms , Databases, Genetic , Humans , Phenotype , Time Factors
3.
J Environ Manage ; 217: 762-774, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29656257

ABSTRACT

Nitrogen (N) and phosphorus (P) play a critical role in agricultural production and cause many environmental disturbances. By combing life cycle assessment (LCA) method with the mass balance principle of substance flow analysis (SFA), this study establishes a nutrient-derived environmental impact assessment (NEIA) model to analyze the environmental impacts caused by nutrient-containing substances of agricultural production in China during 1978-2015. The agricultural production system is composed of crop farming and livestock breeding, and the environmental impacts include energy consumption, global warming, acidification, and eutrophication. The results show all these environmental impacts had increased to 8.22*109 GJ, 5.01*108 t CO2-eq, 2.41*107 t SO2-eq, and 7.18*107 t PO43--eq, respectively. It is noted the energy consumption and the climate change caused by the crop farming were always higher than those from livestock breeding, which were average 60 and two times, respectively. While the acidification and the eutrophication were opposite after 1995 and 2000, even they were similar. This was mainly due to the high N application including synthetic N fertilizer (from 1.33*109 GJ to 2.08*109 GJ), applied manure (from 4.94*108 GJ to 5.65*108 GJ) and applied crop residue (from 2.94*108 GJ to 5.30*109 GJ), while the synthetic N fertilizer was controlled and the livestock expanded rapidly after 1995. Among the sub-categories, the three staple crops (rice, wheat, and maize) contributed greater environmental impacts, which were about two to 10 times as other crops and livestock, due to their high fertilizer uses, sown areas and harvests. While the oil crops and fruit consumed the least energies because of their much lower fertilizer-use intensities. Pig and poultry especially pig also caused obvious effects on environment (even 20 times as other livestock) because of their large quantities and excretions, which emitted much higher N2O and P loss resulting in much higher climate change, acidification and eutrophication than other livestock. Then the study proposes the nutrient management in agricultural production by considering crop production, livestock breeding and dietary adjustment, so that some valuable experiences can be shared by the stakeholders in other Chinese regions.


Subject(s)
Agriculture , Environment , Fertilizers , Animals , China , Crops, Agricultural , Plant Breeding , Swine
4.
Vaccine ; 36(2): 256-263, 2018 01 04.
Article in English | MEDLINE | ID: mdl-29195717

ABSTRACT

BACKGROUND/AIMS: A birth dose of hepatitis B immunoglobulin (HBIG), in combination with hepatitis B vaccine (HepB), is recommended for infants born to hepatitis B surface antigen (HBsAg)-positive mothers. However, the optimal dosage of HBIG remains to be resolved. This prospective cohort study aimed to compare the efficacy of two dosages of HBIG combined with HepB to prevent mother-to-child transmission (MTCT) of HBV. METHODS: From 2009 to 2011, we prospectively enrolled mother-infant pairs with positive maternal HBsAg in China. Infants were assigned to receive one dose of 100 IU or 200 IU HBIG within 12 h of birth according to maternal numbering, followed by completion of the 3-dose 10 µg HepB series. At 7 months, post-vaccination serologic testing (PVST) was performed in 545 and 632 infants in 100 IU and 200 IU HBIG groups, respectively, among whom, 451 and 529 were followed up to 12 months. RESULTS: Maternal and birth characteristics were comparable between infants in 100 IU and 200 IU HBIG groups. At 7 months, the rates of perinatal infection were 1.5% (8/545) and 1.9% (12/632) in 100 IU and 200 IU HBIG groups, respectively (p = .568). One non-responder infant in 200 IU HBIG group became newly infected at 12 months. The antibody to hepatitis B surface antigen (anti-HBs) positive rates were 98.5% (529/537) and 98.2% (609/620) in 100 IU and 200 IU HBIG groups at 7 months, respectively (p = .704), and the corresponding figures were 98.2% (431/439) and 97.1% (496/511) at 12 months (p = .266). The anti-HBs geometric mean concentrations were comparable between two groups at 7 months (707.95 mIU/mL vs. 602.56 mIU/mL, p = .062) and 12 months (245.47 mIU/mL vs. 229.09 mIU/mL, p = .407). CONCLUSIONS: One birth dose of 100 IU HBIG, combined with the HepB series, might be enough for preventing MTCT of HBV in infants born to HBsAg-positive mothers.


Subject(s)
Hepatitis B Antibodies/blood , Hepatitis B Vaccines/administration & dosage , Hepatitis B Vaccines/immunology , Hepatitis B/prevention & control , Immunoglobulins/administration & dosage , Infectious Disease Transmission, Vertical/prevention & control , Adolescent , Adult , China , Female , Follow-Up Studies , Hepatitis B Surface Antigens/blood , Humans , Infant , Infant, Newborn , Male , Pregnancy , Prospective Studies , Treatment Outcome , Young Adult
5.
Vaccine ; 35(48 Pt B): 6627-6633, 2017 12 04.
Article in English | MEDLINE | ID: mdl-29079104

ABSTRACT

BACKGROUND: Antiviral therapy has been documented to reduce perinatal transmission of hepatitis B virus (HBV) in highly viremic mothers. This large prospective cohort study conducted in China aims to delineate the maternal viral threshold for consideration of antiviral prophylaxis in settings with limited resources. METHODS: A total of 1177 mother-infant pairs with positive maternal hepatitis B surface antigen (HBsAg) under current passive-active prophylaxis regimen were enrolled from community health centers in Jiangsu and Henan provinces, China. Maternal hepatitis B e antigen (HBeAg) status and viral load were tested at 36-40 weeks of gestation. Post-vaccination serologic testing was performed at 7 and 12 months of age. RESULTS: HBeAg-positive mothers (419/1177; 35.6%) had significantly higher viral loads, compared with HBeAg-negative mothers (758/1177; 64.4%) (8.12 vs. 2.69 log IU/mL, p < .0001). Twenty infants, born to HBeAg-positive mothers with high viral loads (median, 8.38; range: 7.82-9.22 log IU/mL), were infected at 7 months of age. In contrast, none of the HBeAg-negative mothers transmitted HBV to their offspring. After adjustment for the other risk factor, a higher maternal viral load was significantly associated with a higher risk of transmission (adjusted odds ratio, 3.78; 95% confidence interval: 1.46-9.81; p = .006). The rates of passive-active immunoprophylaxis failure were 0.0% (0/789), 0.0% (0/27), 0.0% (0/32) and 6.1% (20/329) at maternal viral loads of <5, 5-6, 6-7 and ≥7 log IU/mL, respectively. The antibody to hepatitis B surface antigen (anti-HBs) response rate was 98.4% (1138/1157) at 7 months of age. CONCLUSIONS: Results from this study indicate that the maternal viral threshold associated with perinatal transmission of HBV is 7 log IU/mL, which may be appropriate for consideration of antiviral prophylaxis in settings with limited resources.


Subject(s)
Health Resources , Hepatitis B/prevention & control , Infectious Disease Transmission, Vertical/prevention & control , Post-Exposure Prophylaxis/methods , Treatment Failure , Viral Load/methods , Adult , Cohort Studies , DNA, Viral/blood , Female , Hepatitis B Vaccines/administration & dosage , Hepatitis B Vaccines/immunology , Hepatitis B e Antigens/blood , Hepatitis B virus/drug effects , Hepatitis B virus/isolation & purification , Humans , Immunization, Passive/adverse effects , Immunoglobulins/therapeutic use , Infant , Infant, Newborn , Male , Pregnancy , Pregnancy Complications, Infectious/virology , Prospective Studies , Vaccination , Viral Load/drug effects
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