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This article presents a simple, eco-friendly, and green method for the synthesis of silver nanoparticles (AgNPs) from AgNO3 solution utilizing an aqueous extract of Callisia fragrans leaf. The effects of C. fragrans leaf extraction conditions were evaluated. Parameters affecting the synthesis of AgNPs, such as the volume of extract, pH, temperature, and reaction time were investigated and optimized. The obtained AgNPs were analyzed by UV–Vis spectroscopy, X-ray diffraction pattern, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and FTIR techniques. TEM and DLS analyses have shown that the synthesized AgNPs were predominantly spherical in shape with an average size of 48 nm. The zeta potential of the colloidal solution of AgNPs is −27 mV, indicating the dispersion ability of AgNPs. The results of GC–MS and FTIR analyses show the presence of biomolecules in the aqueous extract of C. fragrans leaf that acts as reducing and capping agents for the biosynthesis of AgNPs. The synthesized AgNPs demonstrate anticancer activity against MCF-7, HepG2, KB, LU-1, and MKN-7 cell lines, with inhibitory concentrations at 50% (IC50 values) of 2.41, 2.31, 2.65, 3.26, and 2.40 µg·mL−1, respectively. The obtained results in the study show that the biosynthesized AgNP from C. fragrans leaf extract can be further exploited as a potential candidate for anticancer agents.

This paper presents an improved coyote optimization algorithm (ICOA) for the electric distribution network reconfiguration (EDNR) problem considering unbalanced load. ICOA is first developed by carrying out two improvements on two new solution generation mechanisms of original coyote optimization algorithm (COA). In the first mechanism, ICOA has used the so-far best solution instead of the tendency solution like COA. In the second mechanism, a local search mechanism has been proposed to update the so-far best solution. ICOA determines opened switches in aim to minimize total power losses. In addition, a modified power flow (MPF) method based on the technique of backward/forward sweeps is proposed to solve power flow for unbalanced distribution system. The proposed MPF method has been highly accurate in comparison with the Power System Simulator/Advanced Distribution Engineering Productivity Tool software (PSS/ADEPT). The ICOA together with COA, particle swarm optimization (PSO) and sunflower optimization (SFO) have been implemented on three systems including 25-node, 33-node and 69-node for comparison. As a result, ICOA has outperformed COA, PSO, SFO and other existing methods for the EDNR problem. Consequently, the combination of the proposed MPF method and ICOA for solving EDNR problem with unbalanced load can lead to high effectiveness.

This paper presents a new method based on the artificial ecosystem optimization (AEO) algorithm for finding the shortest tour of the travelling salesman problem (TSP). Wherein, AEO is a newly developed algorithm based on the idea of the energy flow of living organisms in the ecosystem consisting of production, consumption, and decomposition mechanisms. In order to improve the efficiency of the AEO for the TSP problem, the 2-opt movement technique is equipped to enhance the quality of the solutions created by the AEO. The effectiveness of AEO for the TSP problem has been verified on four TSP instances consisting of the 14, 30, 48 and 52 cities. Based on the calculated results and the compared results with the previous methods, the proposed AEO method is one of the effective approaches for solving the TSP problem.

Background and Objectives: Diarrhea is one of the first causes of morbidity and mortality among children, especially in poor and developing countries including Vietnam. For decades, although Vietnam has implemented different health interventions to suppress diarrhea spread, this disease has been continuously concerned as a national health problem. Hence, the aim of this study was to assess ethnic minority mothers’ knowledge, attitude and practice (KAP) associated with diarrhea in children under 5 years old; Then to find out the correlation among KAP, and discover some factors related to good knowledge, positive attitude, correct practice about diarrhea in under 5-year old children of the mothers in Pediatrics Department of Daklak General Hospital, 2014. Method: A community based cross-sectional study was carried out from September 2013 to July 2014 in Pediatrics Department - Daklak General Hospital with the participation of 153 ethnic mothers who has children with diarrhea. The mothers were interviewed directly following the questionnaire, whose structure was adapted from the World Health Organization (WHO) and author Hau Van Pham. The collected data were checked for completeness, consistency and then entered into Epidata 3.1 and analyzed using SPSS 20. Results: The data from 153 participants showed that the ethnic mothers had good knowledge accounted for 39.9%, whereas more than half of ethnic mothers (64.7%) had a positive attitude towards prevention of diarrhea among under-five children. However, the correct practice in taking care of children with diarrhea was not high (40.5%). As expected, there was statistically significant correlation between the mothers’ knowledge and their attitudes (p < 0.001), as well as their practice toward diarrhea treatment (p=0.005). Analyzed data exhibited that knowledge of the mothers about diarrhea was influenced by their differences in socio-demographic factors, including educational level (p

Traditional influenza vaccines generate strain-specific antibodies which cannot provide protection against divergent influenza virus strains. Further, due to frequent antigenic shifts and drift of influenza viruses, annual reformulation and revaccination are required in order to match circulating strains. Thus, the development of a universal influenza vaccine (UIV) is critical for long-term protection against all seasonal influenza virus strains, as well as to provide protection against a potential pandemic virus. One of the most important strategies in the development of UIVs is the selection of optimal targeting antigens to generate broadly cross-reactive neutralizing antibodies or cross-reactive T cell responses against divergent influenza virus strains. However, each type of target antigen for UIVs has advantages and limitations for the generation of sufficient immune responses against divergent influenza viruses. Herein, we review current strategies and perspectives regarding the use of antigens, including hemagglutinin, neuraminidase, matrix proteins, and internal proteins, for universal influenza vaccine development.

Vaccination is the most effective way to prevent influenza virus infections. However, conventional vaccines based on hemagglutinin (HA) have to be annually updated because the HA of influenza viruses constantly mutates. In this study, we produced a 3M2e-3HA2-NP chimeric protein as a vaccine antigen candidate using an Escherichia coli expression system. The vaccination of chimeric protein (15 μg) conferred complete protection against A/Puerto Rico/8/1934 (H1N1; PR8) in mice. It strongly induced influenza virus-specific antibody responses, cytotoxic T lymphocyte activity, and antibody-dependent cellular cytotoxicity. To spare the dose and enhance the cross-reactivity of the chimeric, we used a complex of poly-γ-glutamic acid and alum (PGA/alum) as an adjuvant. PGA/alum-adjuvanted, low-dose chimeric protein (1 or 5 μg) exhibited higher cross-protective effects against influenza A viruses (PR8, CA04, and H3N2) compared with those of chimeric alone or alum-adjuvanted proteins in vaccinated mice. Moreover, the depletion of CD4+ T, CD8+ T, and NK cells reduced the survival rate and efficacy of the PGA/alum-adjuvanted chimeric protein. Collectively, the vaccination of PGA/alum-adjuvanted chimeric protein induced strong protection efficacy against homologous and heterologous influenza viruses in mice, which suggests that it may be a promising universal influenza vaccine candidate.

This paper presents a new method based on the artificial ecosystem optimization (AEO) algorithm for finding the shortest tour of the travelling salesman problem (TSP). Wherein, AEO is a newly developed algorithm based on the idea of the energy flow of living organisms in the ecosystem consisting of production, consumption and decomposition mechanisms. In order to improve the efficiency of the AEO for the TSP problem, the 2-opt movement technique is equipped to enhance the quality of the solutions created by the AEO. The effectiveness of AEO for the TSP problem has been verified on four TSP instances consisting of the 14, 30, 48 and 52 cities. Based on the calculated results and the compared results with the previous methods, the proposed AEO method is one of the effective approaches for solving the TSP problem.

Display Omitted The runner-root algorithm (RRA) is adapted to solve the network reconfiguration problem.Five objectives namely power loss, load balancing among the branches, load balancing among the feeders, number of switching operations and node voltage deviation are considered.The proposed RRA method is applied to the 33-bus and 70-bus test networks for evaluation.The proposed RRA method has better performance in comparison to other methods. This paper presents a runner-root algorithm (RRA) for electric distribution network reconfiguration (NR) problem. The considered NR problem in this paper is to minimize real power loss, load balancing among the branches, load balancing among the feeders as well as number of switching operations and node voltage deviation using max-min method for selection of the final compromised solution. RRA is equipped with two explorative tools, which are random jumps with large steps and re-initialization strategy to escape from local optimal. Moreover, RRA is also equipped with an exploitative tool to search around the current best solution with large and small steps to ensure the obtained result of global optimization. The effectiveness of the applied RRA in both single- and multi-objective has been tested on 33-node and 70-node distribution network systems and the obtained test results have been compared to those from other methods in the literature. The simulation results show that the applied RRA can be an efficient method for network reconfiguration problems with single- and multi-objective.

Foot-and-mouth disease (FMD) is a highly contagious and economically devastating disease affecting cloven-hoofed livestock worldwide. FMD virus (FMDV) type A is one of the most common causes of FMD outbreaks among the seven FMDV serotypes, and its serological diagnosis is therefore important to confirm FMDV type A infection and to determine FMD vaccine efficacy. Here, we generated monoclonal antibodies (mAbs) specific to FMDV type A via hybridoma systems using an inactivated FMDV type A (A22/Iraq/1964) and found 4 monoclones (#29, #106, #108, and #109) with high binding reactivity to FMDV type A among 594 primary clones. In particular, the #106 mAb had a higher binding reactivity to the inactivated FMDV type A than the other mAbs and a commercial mAb. Moreover, the #106 mAb showed no cross-reactivity to inactivated FMDV type South African territories 1, 2, and 3, and low reactivity to inactivated FMDV type O (O1 Manisa). Importantly, the solid-phase competitive ELISA (SPCE) using horseradish peroxidase (HRP)-conjugated #106 mAb detected FMDV type A-specific Abs in sera from FMD type A-vaccinated cattle more effectively than a commercial SPCE. These results suggest that the newly developed FMDV type A-specific mAb might be useful for diagnostic approaches for detecting Abs against FMDV type A.

The use of a good vaccine adjuvant may induce a higher immunogenicity profile of vaccine antigens. Here, we developed a new adjuvant by combining poly-γ-glutamic acid (γ-PGA) with alum (PGA/Alum) and investigated its ability to enhance the immunogenicity and the cross-reactive efficacy of pandemic H1N1 (pH1N1) influenza vaccine antigen. PGA/Alum enhanced antigen delivery to draining lymph nodes and antigen-specific immunogenicity in mice using OVA as a model antigen. It also greatly increased OVA-specific antibody production, cytotoxic T lymphocyte (CTL) activity, and antibody-dependent cellular cytotoxicity (ADCC). These abilities of PGA/Alum improved the protective efficacy of pH1N1 vaccine antigen by increasing hemagglutination-inhibition titers, enhancing ADCC and CTL activity, and speeding viral clearance following homologous viral challenge. Importantly, the cross-protective efficacy of pH1N1 vaccine against heterologous viruses [A/Puerto Rico/8/34 (H1N1) and A/Hong Kong/1/1968 (H3N2)] was significantly enhanced by PGA/Alum, and cross-reactive ADCC and CTL activities were observed. Together, our results strongly suggest that PGA/Alum may be a promising vaccine adjuvant for preventing influenza and other infectious diseases.

Emerging influenza viruses pose an extreme global risk to human health, resulting in an urgent need for effective vaccination against influenza infection. Adjuvants are vital components that can improve vaccine efficacy, yet only a few adjuvants have been licensed in human vaccines. Here, we investigate the adjuvant effects of Escherichia coli-produced monophosphoryl lipid A (MPL), named EcML, in enhancing the immunogenicity and efficacy of an influenza vaccine. Similar to MPL, EcML activated dendritic cells and enhanced the antigen processing of cells in vitro. Using ovalbumin (OVA) as a model antigen, EcML increased OVA-specific antibody production, cytotoxic T lymphocyte activity. The safety of EcML was demonstrated as being similar to that of MPL by showing not significant in vitro cell cytotoxicity but transient systemic inflammatory responses within 24 h in OVA immunized mice. Importantly, mice vaccinated with pandemic H1N1 (pH1N1) vaccine antigen, combined with EcML, were fully protected from pH1N1 virus infection by enhanced influenza-specific antibody titers, hemagglutination inhibition titers, and IFN-&gamma, secreting cells. Taken together, our results strongly suggest that EcML might be a promising vaccine adjuvant for preventing influenza virus infection.

The epidemic and pandemic influenza viruses result in substantial morbidity and mortality in humans. Vaccination is the most effective way to prevent influenza virus infection. In this study, we cloned the conserved regions of influenza A virus, extracellular domain of matrix protein 2 (M2e), hemagglutinin 2 (HA2) and nucleoprotein (NP). Then, we generated fusion (M2e-HA2-NP) protein as a universal vaccine antigen candidate. γ-PGA/Alum (PA) was used as an adjuvant to enhance the efficacy of fusion protein. In mice challenged with influenza viruses, fusion protein (15 μg) provided 100% protection against A/Puerto Rico/8/1934 (H1N1; PR8) or A/California/04/09 (pH1N1; CA04) and 80% protection against H3N2 (a reassortant virus carrying HA and NA genes of A/Hong Kong/1/68). In dose-sparing effect experiments, low dose (1 or 5 μg) of fusion protein with PA provided the same protection comparable to 15 μg of fusion protein against H1N1, pH1N1 and H3N2. Humoral and cellular immunities against heterologous influenza viruses were significantly enhanced in mice vaccinated with fusion protein mixed with PA compared with alum-adjuvanted fusion protein. Taken together, the fusion protein adjuvanted with PA may be a good vaccine candidate showing heterosubtypic cross-reactivity.

Totally, 26 collections, 17 from Korea and 9 from China, were investigated for their sequences of 5S rDNA, especially the non-transcribed spacers (NTSs). Sequences of 5S rDNA were isolated by PCR using the primers, 5s-rRNA1 and 5s-rRNA2. Genomic DNA PCR produced single amplification of 300, 330, or 350 base pair fragments. Sequence analysis revealed that all inserts contained the part of 5S rDNA gene sequence and the full length of the NTS region. Three different sizes of the fragments were confirmed due to different size of NTS and their length were 300bp, 330bp and 350bp, respectively. Among 17 Korean foxtail millets tested, 14 collections showed single 300bp amplification. Longest fragment amplification, 350bp, was obtained only from the foxtail millet from China origin, even though 2 of them include 300bp fragment. CLUSTALW multiple alignments of 26 foxtail millets clearly revealed 4 areas with certain degree of sequence heterogeneity (region I, II, III, IV). Among 4 boxed areas, foxtail millet genotypes from China have distinct insertion especially in region III. Five of them have extra insertion of sequence and their additional sequences were either 45 or 48 base pair. Three Korean foxtail millets have 32 bp insertion. Other 8 Korean collections have short insert sequences (6 to 8 bp), 3 with 8 bp and 5 with 6 bp. In addition to insert, deletion sequences were also confirmed as major deletion was observed in region II of Chinese collection. The size of deletion was 7 bp long. According to phylogenic tree constructed using MEGA4 program, clear grouping was not revealed. To obtain more convincing results various collections from many countries should be obtained and analyzed to distinguish different germplasm from different origin.

Vaccination is the most effective strategy to protect against infectious diseases and adjuvants are proven to be the key component in vaccines capable of improving antigen-specific immune responses. Conventional vaccine adjuvants, however, still have several limitations such as safety concerns and insufficient induction of vaccine efficacy. Here, we developed a novel adjuvant by combining poly-gamma glutamic acid (γ-PGA) with alum that is already approved for human use worldwide. The physiochemical properties, efficacy, and underlying mechanism of the PGA/Alum as an adjuvant were investigated using ovalbumin (OVA) as a model antigen in vivo and in vitro. PGA/Alum-OVA administered mice showed the robust increase of antigen-specific humoral and cellular immune responses compared to mice administered with γ-PGA-OVA or alum-OVA. Importantly, the PGA/Alum-OVA-induced antibodies had significantly higher antibody-dependent cellular cytotoxicity (ADCC) activity. The enhanced activation and antigen processing of dendritic cells (DCs) and the facilitated migration of antigen-loaded DCs from the injection sites to draining lymph nodes were observed in PGA/Alum-OVA administered mice. Finally, the efficacy of the PGA/Alum as a vaccine adjuvant was evaluated using pandemic H1N1 influenza vaccine antigen. The PGA/Alum drastically enhanced protective efficacy of the pandemic H1N1 vaccine against influenza virus infection. Taken together, PGA/Alum may be a promising adjuvant to improve the influenza vaccine efficacy.