Graphene nanosheets (GNSs) have been considered as potential conductive additives for electrodes in Li-ion batteries to replace the existing carbon black (CB). Graphene has exceptionally high aspect ratio and excellent electrical conductivity, enabling the formation of extensive conductive networks at a much lower content than CB. This paper reports the beneficial effects of GNSs with a low percolation threshold on electrochemical performance of Li(4)Ti(5)O(12) (LTO) anodes. The experimental results show that the GNSs with a diameter of 46 μm and a thickness of 4.5 nm have a percolation threshold of 1.8 wt%. The prediction based on the interparticle distance concept gives a percolation threshold of 0.54 wt% for GNSs, which is almost an order of magnitude lower than that for CB particles. The substantially low percolation along with a high electrical conductivity of GNSs explains why the LTO anodes containing only 5 wt% GNSs deliver a much better rate capability than those with 15 wt% CB. However, a higher GNS content of 10 wt% results in re-stacking GNSs, deteriorating the diffusion of Li ions through the thickness of GNSs. The parametric study indicates that the percolation threshold of GNSs is inversely proportional to the aspect ratio of GNSs.

A facile strategy is developed based on a sol-gel method to prepare lithium titanate (Li 4 Ti 5 O 12 , LTO)carbon nanofiber (CNF) composites as anode in Li-ion batteries (LIBs). Depending on the conductive CNF and carbon black (CB) additive contents added in the electrode, the resultant composite particles present either an urchin-like or a corn-dog structure with largely different electronic conductivities and associated electrochemical properties. When small amounts of both one-dimensional CNF and zerodimensional CB particles, 5.0 wt% each, are present, conductive networks are established within the urchin-like LTO secondary particles by the penetrating multiple CNFs, whereas the CB particles attached onto the surface of the LTO particles connect the gaps between them, being able to form extensive three-dimensional conductive networks across the whole composites. The electrodes made from this composite deliver a remarkable capacity of 123 mA h g À1 when charged/discharged at 15 C, which is much higher than 91 mA h g À1 for those made from the neat LTO powders, a reflection of significant improvements in both the conductivity and Li ion diffusion coefficient in the composite electrode. When the CNF content is increased to 10 wt%, corn-dog shaped composites are formed consisting of individual CNFs penetrating the elongated LTO secondary particles along the axial direction with limited conductive networks. The electrodes made from this composite present much poorer capacities at all current rates than those with an urchin-like structure. These intriguing observations verify that both the structure of the active material and the conductivity of the electrode play important roles in delivering high capacities and rate capabilities.

bStreptococcus pneumoniae is a Gram-positive and human-restricted pathogen colonizing the nasopharynx with an absence of clinical symptoms as well as a major pathogen causing otitis media (OM), one of the most common childhood infections. Upon bacterial infection, neutrophils are rapidly activated and recruited to the infected site, acting as the frontline defender against emerging microbial pathogens via different ways. Evidence shows that interleukin 17A (IL-17A), a neutrophil-inducing factor, plays important roles in the immune responses in several diseases. However, its function in response to S. pneumoniae OM remains unclear. In this study, the function of IL-17A in response to S. pneumoniae OM was examined using an in vivo model. We developed a model of acute OM (AOM) in C57BL/6 mice and found that neutrophils were the dominant immune cells that infiltrated to the middle ear cavity (MEC) and contributed to bacterial clearance. Using IL-17A knockout (KO) mice, we found that IL-17A boosted neutrophil recruitment to the MEC and afterwards induced apoptosis, which was identified to be conducive to bacterial clearance. In addition, our observation suggested that the p38 mitogen-activated protein kinase (MAPK) signaling pathway was involved in the recruitment and apoptosis of neutrophils mediated by IL-17A. These data support the conclusion that IL-17A contributes to the host immune response against S. pneumoniae by promoting neutrophil recruitment and apoptosis through the p38 MAPK signaling pathway.

Pneumolysin (Ply) and its variants are protective against pneumococcal infections in animal models, and as a Toll-like receptor 4 agonist, pneumolysin has been reported to be a mucosal adjuvant. DnaJ has been approved as a useful candidate vaccine protein; we therefore designed novel fusion proteins of DnaJ with a form of Ply that has a deletion of A146 (⌬A146Ply-DnaJ [the C terminus of ⌬A146Ply connected with the N terminus of DnaJ] and DnaJ-⌬A146Ply [the C terminus of DnaJ connected with the N terminus of ⌬A146Ply]) to test whether they are protective against focal and lethal pneumococcal infections and their potential protective mechanisms. The purified proteins were used to intranasally immunize the animals without additional adjuvant. Immunization with DnaJ-⌬A146Ply or DnaJ plus ⌬A146Ply (Ply with a single deletion of A146) could significantly reduce S. pneumoniae colonization in the nasopharynx and lung relative with DnaJ alone. Additionally, we observed the best protection for DnaJ⌬A146Ply-immunized mice after challenge with lethal doses of S. pneumoniae strains, which was comparable to that achieved by PPV23. Mice immunized with DnaJ-⌬A146Ply produced significantly higher levels of anti-DnaJ IgG in serum and secretory IgA (sIgA) in saliva than those immunized with DnaJ alone. The production of IL-17A was also striking in DnaJ-⌬A146Ply-immunized mice. IL-17A knockout (KO) mice did not benefit from DnaJ-⌬A146Ply immunization in colonization experiments, and sIgA production was impaired in IL-17A KO mice. Collectively, our results indicate a mucosal adjuvant potential for ⌬A146Ply and that, without additional adjuvant, DnaJ-⌬A146Ply fusion protein exhibits extensive immune stimulation and is effective against pneumococcal challenges, properties which are partially attributed to the IL-17A-mediated immune responses.

bMucosal immunization with attenuated vaccine can protect against pneumococcal invasion infection, but the mechanism was unknown. Our study found that mucosal delivery with the live attenuated SPY1 vaccine strain can confer T cell-and B cell-dependent protection against pneumococcal colonization and invasive infection; yet it is still unclear which cell subsets contribute to the protection, and their roles in pneumococcal colonization and invasion remain elusive. Adoptive transfer of anti-SPY1 antibody conferred protection to naive MT mice, and immune T cells were indispensable to protection examined in nude mice. A critical role of interleukin 17A (IL-17A) in colonization was demonstrated in mice lacking IL-17A, and a vaccine-specific Th2 immune subset was necessary for systemic protection. Of note, we found that SPY1 could stimulate an immunoregulatory response and that SPY1-elicited regulatory T cells participated in protection against colonization and lethal infection. The data presented here aid our understanding of how live attenuated strains are able to function as effective vaccines and may contribute to a more comprehensive evaluation of live vaccines and other mucosal vaccines. Vaccination is an indispensable strategy to prevent infection caused by Streptococcus pneumoniae (S. pneumoniae), which is estimated to lead to a mortality rate of more than 50 deaths in every 1,000 births in children under 5 years of age in some countries (1). The commercially available 23-valent polysaccharide vaccine contains the most common serotypes that cause pneumococcal infection and is effective in adults but fails to protect children of less than 2 years of age, who are most vulnerable to pneumococcal infection. The recent extensive introduction of conjugated capsular polysaccharide vaccine (PCV) has drastically decreased the child morbidity and mortality caused by strains of S. pneumoniae expressing capsular serotypes included in the vaccine. However, the serotype coverage of PCV is limited, and a growing body of evidence showed that PCV could induce selective pressure and gradual replacement with nonvaccine serotypes (serotype replacement) (2, 3). The conjugated vaccine is also very expensive and is complex in design, making more difficult its application in the low-income countries that have the highest burden of S. pneumoniae infections (4).As a consequence of these shortcomings with the commercially available S. pneumoniae vaccines, other approaches have been explored, including protein antigen vaccines, killed whole-cell S. pneumoniae vaccines, or attenuated live S. pneumoniae vaccines (5, 6). The wide range of antigenic molecules present in live attenuated vaccines promises that the immune responses they induce are likely to be multiple and powerful and may also more closely mimic those obtained in natural infection than immune responses to a vaccine using a subcomponent or killed bacteria (7). Some live bacterial vaccines have been clinically used, including the Mycobacterium bovis BCG (8) and vaccines for prev...

Background Since pre-exposure prophylaxis (PrEP) is mainly prescribed to high-risk uninfected individuals, consistent condom use (CCU) continues to be recommended as an inexpensive, feasible, practical and acceptable way to prevent the general population from acquiring and transmitting HIV through sexual intercourse. The objective of this cross-sectional study was to compare the relative importance of various determinants of CCU among sexually experienced undergraduates in mainland China so as to assess and subsequently to suggest ways to eliminate inequities in its use. Method From September 10, 2018, to January 9, 2019, an anonymous self-administered online questionnaire was voluntarily completed by 12,750 participants distributed across 30 provinces in mainland China (except for Tibet). The present analysis was restricted to 2054 sexually experienced undergraduates. Pearson’s chi-square test and Logistic regression models were chosen to analyze the factors associated with CCU. Results The overall rate of CCU was 61.3% [95% confidence interval (CI) = 59.2–63.4%]. CCU was inequitably distributed since enabling factors exerted greater effects than predisposing and need variables. Compared with heterosexual men, heterosexual women [adjusted odds ratio (AOR) = 0.78, 95% confidence interval (CI):0.64–0.96)], non-heterosexuals men (AOR = 0.64, 95% CI:0.45–0.92) and women (AOR = 0.68, 95% CI:0.47–0.99) were less prone to using condoms consistently. Those with more resources [i.e., higher levels of self- efficacy for condom use (AOR = 2.86, 95% CI:2.35–3.49) and being knowledgeable of the national AIDS policy (AOR = 1.50, 95% CI:1.23–1.82)], and those with lower need for condoms [i.e., late initiation of sexual activity (AOR = 1.34, 95% CI:1.09–1.64) and single sexual partner (AOR = 1.68,95% CI:1.21–2.33)] were more likely to be consistent condom users. Conclusions In order to increase consistency of condom use and simultaneously reduce the remaining inequities, a comprehensive intervention measure should be taken to target heterosexual women, non-heterosexual men and women, and those with higher need for condoms, improve their condom use self- efficacy and raise their awareness of the national AIDS policy.

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Fungal immunomodulatory proteins (FIPs) are a group of proteins found in fungi, which are extensively studied for their immunomodulatory activity. Currently, more than 38 types of FIPs have been described. Based on their conserved structure and protein identity, FIPs can be classified into five subgroups: Fve-type FIPs (Pfam PF09259), Cerato-type FIPs (Pfam PF07249), PCP-like FIPs, TFP-like FIPs, and unclassified FIPs. Among the five subgroups, Fve-type FIPs are the most studied for their hemagglutinating, immunomodulating, and anti-cancer properties. In general, these small proteins consist of 110-125 amino acids, with a molecular weight of ∼13 kDa. The other four subgroups are relatively less studied, but also show a noticeable influence on immune cells. In this review, we summarized the protein modifications, 3-dimensional structures and bioactivities of all types of FIPs. Moreover, structure-function relationship of FIPs has been discussed, including relationship between carbohydrate binding module and hemagglutination, correlation of oligomerization and cytokine induction, relevance of glycosylation and lymphocyte activation. This summary and discussion may help gain comprehensive understanding of FIPs' working mechanisms and scope future studies.