Spatiotemporally comparative analysis of three common infectious diseases in China during 2013-2015.

BACKGROUND: Dengue fever (DF), influenza, and hand, foot, and mouth disease (HFMD) have had several various degrees of outbreaks in China since the 1900s, posing a serious threat to public health. Previous studies have found that these infectious diseases were often prevalent in the same areas and during the same periods in China. METHODS: This study combined traditional descriptive statistics and spatial scan statistic methods to analyze the spatiotemporal features of the epidemics of DF, influenza, and HFMD during 2013-2015 in mainland China at the provincial level. RESULTS: DF got an intensive outbreak in 2014, while influenza and HFMD were stable from 2013 to 2015. DF mostly occurred during August-November, influenza appeared during November-next March, and HFMD happened during April-November. The peaks of these diseases form a year-round sequence; Spatially, HFMD generally has a much higher incidence than influenza and DF and covers larger high-risk areas. The hotspots of influenza tend to move from North China to the southeast coast. The southeastern coastal regions are the high-incidence areas and the most significant hotspots of all three diseases. CONCLUSIONS: This study suggested that the three diseases can form a year-round sequence in southern China, and the southeast coast of China is a particularly high-risk area for these diseases. These findings may have important implications for the local public health agency to allocate the prevention and control resources.

Development and preparation of a low-immunogenicity porcine dermal scaffold and its biocompatibility assessment.

Acellular dermal matrix (ADM) has been widely used in repair and reconstruction of tissue defect. Therapeutic effect of porcine ADM (PADM) is inferior to that of human ADM (HADM). Relatively high immunogenicity and the resulting strong inflammatory response are major issue in application of PADM. We therefore treated reticular layer PADM (Rl-PADM) with matrix metalloproteinase-7 (MMP-7) and obtained a low-immunogenicity porcine dermal scaffold (LIPDS). Highly immunogenic components, tissue structure, cytocompatibility, and postgrafting histological changes of LIPDS were further investigated. Compared with Rl-PADM, LIPDS showed that the epithelial root sheath, cell debris, laminin, and type IV collagen were almost entirely removed, the structure remained normal, and the interfibrous space was relatively enlarged. Cytocompatibility of LIPDS was similar to that of HADM but superior to Rl-PADM. With regard to the extent of tissue ingrowth in terms of host fibroblasts infiltration and vascularization, LIPDS exhibited clear advantages over Rl-PADM after they had been subcutaneously transplanted in a rat model. In addition, no excessive inflammatory response was observed in LIPDS group up to 28 days postgraft, and the morphosis of collagenous fibers kept essentially normal. However, there were stronger inflammatory response and obvious collagen spallation in Rl-PADM group. The processes of integration and remodeling after the LIPDS grafting were similar to those of a normal wound healing response. The LIPDS graft was vascularized at a relatively high speed. Thus, as an implantable scaffold material, LIPDS is a superior template for guiding tissue regeneration and remodeling.

Liposome-encapsulated cinnamaldehyde enhances zebrafish (Danio rerio) immunity and survival when challenged with Vibrio vulnificus and Streptococcus agalactiae.

Cinnamaldehyde, which is extracted from cinnamon, is a natural compound with activity against bacteria and a modulatory immune function. However, the antibacterial activity and immunostimulation of cinnamaldehyde in fish has not been well investigated due to the compound's poor water solubility. Thus, liposome-encapsulated cinnamaldehyde (LEC) was used to evaluate the effects of cinnamaldehyde on in vitro antibacterial activity against aquatic pathogens and in vivo immunity and protection parameters against Vibrio vulnificus and Streptococcus agalactiae. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) as well as bactericidal agar plate assay results demonstrated the effective bacteriostatic and bactericidal potency of LEC against Aeromonas hydrophila, V. vulnificus, and S. agalactiae, as well as the antibiotic-resistant Vibrio parahaemolyticus and Vibrio alginolyticus. Bacteria challenge test results demonstrated that LEC significantly enhances the survival rate and inhibits bacterial growth in zebrafish infected with A. hydrophila, V. vulnificus, and S. agalactiae. A gene expression study using a real-time PCR showed that LEC immersion-treated zebrafish had increased endogenous interleukin (IL)-1ß, IL-6, IL-15, IL-21, tumor necrosis factor (TNF)-α, and interferon (INF)-γ expression in vivo. After the zebrafish were infected with V. vulnificus or S. agalactiae, the LEC immersion treatment suppressed the expression of the inflammatory cytokines IL-1ß, IL-6, IL-15, NF-κb, and TNF-α and induced IL-10 and C3b expression. These findings demonstrate that cinnamaldehyde exhibits antimicrobial activity against aquatic pathogens, even antibiotic-resistant bacterial strains and immune-stimulating effects to protect the host's defenses against pathogen infection in bacteria-infected zebrafish. These results suggest that LEC could be used as an antimicrobial agent and immunostimulant to protect bacteria-infected fish in aquaculture.

Review of lipoic acid: From a clinical therapeutic agent to various emerging biomaterials.

Lipoic acid (LA), an endogenous small molecule in organisms, has been extensively used for the highly efficient clinical treatment of malignant diseases, which include diabetes, Alzheimer's disease, and cancer over the past seven decades. Tremendous progresses have been made on the use of LA in nanomedicine for the development of various biomaterials because of its unique biological properties and highly adaptable structure since the first discovery. However, there are few reviews thus far, to our knowledge, summarizing this hot subject of research of LA and its derived biomaterials. For this purpose, we present herein the first comprehensive summary on the design and development of LA and its derived materials for biomedical applications. This review first discusses the therapeutic use of LA followed by the description of synthesis and preclinical study of LA-derived-small molecules. The applications of various LA and poly (lipoic acid) (PLA)-derived-biomaterials are next summarized in detail with an emphasis on the use of LA for the design of biomaterials and the diverse properties. This review describes the development of LA from a clinical therapeutic agent to a building unit of various biomaterials field, which will promote the further discovery of new therapeutic uses of LA as therapeutic agents and facile development of LA-based derivates with greater performance for biomedical applications.

[Interaction of lactoferrin and its peptides with DPPC and DPPG liposomes studied by Raman spectroscopy].

Interaction of lactoferrin and its peptides LfcinB4-14 and LfampinB with dipalmitoylglycero-phosphocholine (DPPC) and dipalmitoylglycero-phosphoglycerol (DPPG) liposomes were studied by means of Raman spectroscopy. In our study, conformational changes in the phospholipid molecules were investigated by measuring the intensities of 2 847 and 2 882 cm(-1) Raman bands which are assigned to acyl chains' symmetric and asymmetric C-H stretching vibrations. The addition of lactoferrin and its peptides LfcinB4-14 and LfampinB caused a decrease in the 2 882 cm(-1) intensity of DPPG liposomes, thus the order parameter for the lateral interactions between chains S(lat) decreased from 0.19 to 0.17, 0.14 and 0.12 respectively. On the contrary, the intensities at 2 847 and 2 882 cm(-1) of DPPC liposomes were poorly affected by lactoferrin and its peptides. The results show that lactoferrin and its peptides present a stronger effect on the molecular structure and order degree of anionic lipid DPPG than that of zwitterionic lipid DPPC. This suggests that lactoferrin, LfcinB4-14 and LfampinB can interact and combine with the negatively charged DPPG liposomes by electrostatic interaction and perform its antibacterial activity. Besides, LfcinB4-14 and LfampinB can affect the lipid more strongly than lactoferrin.

Synergistic action between extracellular products from white-rot fungus and cellulase significantly improves enzymatic hydrolysis.

With a set of perfect extracellular lignocellulolytic enzymes, white-rot fungus has been recognized as playing an important role in the degradation of lignocellulose materials, which leads to the possibility of creating a composite enzymatic system with high hydrolysis efficiency in vitro. Echinodontium taxodii is a promising white-rot fungus for biologic pretreatment. In this study, we extracted the extracellular products of E. taxodii under solid-state fermentation conditions, mixed the extracellular products with cellulase to build a composite enzymatic system, and systematically evaluated the effect of this system on the hydrolysis of acid-pretreated and raw maize stovers. We found that the extracellular products from E. taxodii could significantly improve the hydrolysis efficiency of cellulase, with a synergistic action between the extracellular products and cellulase. Corn stovers treated with extracellular products were suitable for the enzymatic hydrolysis of cellulase. Furthermore, we found that pure proteins from the extracellular products were not sufficient to generate synergistic action. This finding suggests that non-protein substances may also be involved in the synergistic action between the extracellular products and cellulase.

One-pot preparation of nanoporous Ag-Cu@Ag core-shell alloy with enhanced oxidative stability and robust antibacterial activity.

Metallic core-shell nanostructures have inspired prominent research interests due to their better performances in catalytic, optical, electric, and magnetic applications as well as the less cost of noble metal than monometallic nanostructures, but limited by the complicated and expensive synthesis approaches. Development of one-pot and inexpensive method for metallic core-shell nanostructures' synthesis is therefore of great significance. A novel Cu network supported nanoporous Ag-Cu alloy with an Ag shell and an Ag-Cu core was successfully synthesized by one-pot chemical dealloying of Zr-Cu-Ag-Al-O amorphous/crystalline composite, which provides a new way to prepare metallic core-shell nanostructures by a simple method. The prepared nanoporous Ag-Cu@Ag core-shell alloy demonstrates excellent air-stability at room temperature and enhanced oxidative stability even compared with other reported Cu@Ag core-shell micro-particles. In addition, the nanoporous Ag-Cu@Ag core-shell alloy also possesses robust antibacterial activity against E. Coli DH5α. The simple and low-cost synthesis method as well as the excellent oxidative stability promises the nanoporous Ag-Cu@Ag core-shell alloy potentially wide applications.

Glucosylation of Smoke-Derived Volatiles in Grapevine (Vitis vinifera) is Catalyzed by a Promiscuous Resveratrol/Guaiacol Glucosyltransferase.

Vinification of grapes (Vitis vinifera) exposed to forest fire smoke can yield unpalatable wine due to the presence of taint compounds from smoke and the release of smoke derived volatiles from their respective glycosides during the fermentation process or in-mouth during consumption. To identify glycosyltransferases (GTs) involved in the formation of glycosidically bound smoke-derived volatiles we performed gene expression analysis of candidate GTs in different grapevine tissues. Second, substrates derived from bushfire smoke or naturally occurring in grapes were screened with the candidate recombinant GTs. A resveratrol GT (UGT72B27) gene, highly expressed in grapevine leaves and berries was identified to be responsible for the production of the phenolic glucosides. UGT72B27 converted the stilbene trans-resveratrol mainly to the 3-O-glucoside. Kinetic analyses yielded specificity constants (kcat/KM) of 114, 17, 9, 8, and 2 mM-1 s-1 for guaiacol, trans-resveratrol, syringol, methylsyringol, and methylguaiacol, respectively. This knowledge will help to design strategies for managing the risk of producing smoke-affected wines.

A Novel Bio-carrier Fabricated Using 3D Printing Technique for Wastewater Treatment.

The structure of bio-carriers is one of the key operational characteristics of a biofilm reactor. The goal of this study is to develop a series of novel fullerene-type bio-carriers using the three-dimensional printing (3DP) technique. 3DP can fabricate bio-carriers with more specialized structures compared with traditional fabrication processes. In this research, three types of fullerene-type bio-carriers were fabricated using the 3DP technique and then compared with bio-carrier K3 (from AnoxKaldnes) in the areas of physicochemical properties and biofilm growth. Images acquired by 3D profiling and SEM indicated that the surface roughness of the 3DP bio-carrier was greater than that of K3. Furthermore, contact angle data indicated that the 3DP bio-carriers were more hydrophilic than K3. The biofilm on the 3DP bio-carriers exhibited higher microbial activity and stronger adhesion ability. These findings were attributed to excellent mass transfer of the substrate (and oxygen) between the vapour-liquid-solid tri-phase system and to the surface characteristics. It is concluded that the novel 3DP fullerene-type bio-carriers are ideal carriers for biofilm adherence and growth.

Composition of EPS fractions from suspended sludge and biofilm and their roles in microbial cell aggregation.

The adhesion and aggregation properties of microbial cell are closely related to extracellular polymeric substances (EPS). In this work, the composition and physicochemical characteristics of EPS in biofilm and suspended sludge (S-sludge) were determined to evaluate their roles in microbial cell aggregation. Raman spectroscopy and three-dimensional fluorescence spectra have been employed to reveal each EPS fraction in different composition. The flocculating capacity of each EPS fraction in the S-sludge shows extraordinary activity, comparing its counterpart in biofilm. Microbial cell surfaces present high hydrophobicity and increased zeta potentials upon EPS extraction. In addition, the respective contribution of EPS to cell aggregating was elucidated. The contribution of combined SEPS and LB-EPS was 23% for S-sludge sample, whereas that was negligible for biofilm sample. The contribution of LB-EPS and TB-EPS were 16% and 30% for S-sludge sample, and -6% and negligible for biofilm sample, respectively. Therefore, EPS promoted the S-sludge cells to aggregate, while in contrast, they showed a negligible or negative effect on the biofilm cells aggregating.

Drug release characteristics from chitosan-alginate matrix tablets based on the theory of self-assembled film.

The aim of this study was to better understand the underlying drug release characteristics from chitosan-alginate matrix tablets containing different types of drugs. Theophylline, paracetamol, metformin hydrochloride and trimetazidine hydrochloride were used as model drugs exhibiting significantly different solubilities (12, 16, 346 and >1000 mg/ml at 37 °C in water). A novel concept raised was that drugs were released from chitosan-alginate matrix tablets based on the theory of a self-assembled film-controlled release system. The film was only formed on the surface of tablets in gastrointestinal environment and originated from chitosan-alginate polyelectrolyte complex, confirmed by differential scanning calorimetry characterization. The formed film could decrease the rate of polymer swelling to a degree, also greatly limit the erosion of tablets. Drugs were all released through diffusion in the hydrated matrix and polymer relaxation, irrespective of the drug solubility. The effects of polymer level and initial drug loading on release depended on drug properties. Drug release was influenced by the change of pH. In contrast, the impact of ionic strength of the release medium within the physiological range was negligible. Importantly, hydrodynamic conditions showed a key factor determining the superiority of the self-assembled film in controlling drug release compared with conventional matrix tablets. The new insight into chitosan-alginate matrix tablets can help to broaden the application of this type of dosage forms.

Microscale analysis of in vitro anaerobic degradation of lignocellulosic wastes by rumen microorganisms.

Anaerobic degradation of lignin in waste straw by ruminal microbes was directly observed using atomic force microscope (AFM). A series of high-resolution AFM images of the straw surface in the biodegradation show that the wax flakelets and lignin granules covering the straw surface were removed by the rumen microorganisms. Such degradation resulted in an exposure of cellulose fibers located inside the straw. The appearance of holes and microfibers in fermentation reveals that tunneling might be one of the ways for rumen microorganisms to attack the straw. Increases in the atomic ratio of oxygen to carbon (O/C) and the ratio C2/C3 in C1s spectra of X-ray photoelectron spectroscopy confirm that more cellulose was exposed on the surface after the anaerobic fermentation of straw. Gas chromatography/mass spectrometry analytical results demonstrate the decomposition of lignin by rumen microorganisms. Fourier transform infrared spectroscopy spectra and the measurement of degradation efficiency of the main straw components further verify these microscaled observations.

[Inhibitory effects of survivin antisense oligonucleotide on drug-resistant human ovarian cancer cell COC1/DDP].

BACKGROUND & OBJECTIVE: Recent studies have shown that survivin is an anti-apoptosis gene, which plays an important role in the carcinogenesis and drug resistance of ovarian cancer. This study was designed to explore the effects of liposome-survivin antisense oligonucleotide (Lip-ASODN) on the growth,apoptosis,and cell cycle distribution of drug-resistant human ovarian cancer cell line COC1/DDP. METHODS: Survivin-ASODN were transfected into COC1/DDP cells mediated by lipofectin. The proliferation of COC1/DDP cells was assessed by cyto-dynamics and MTT assay. The mRNA expression of survivin was determined by reverse transcription- polymerase chain reaction (RT-PCR). The caspase-3 protein activity was measured by Western blot analysis. The apoptotic rate and cell cycle distribution were estimated by flow cytometry (FCM). RESULTS: Compared with Lip-SODN and Lip alone groups, the proliferation of COC1/DDP cells after cultured with Lip-ASODN has been significantly inhibited, its inhibitory rate was (68.3+/-6.2)% after cultured for 72 hours (P< 0.05). The mRNA expression of survivin in Lip-ASODN group was significantly decreased, while the caspase-3 activity increased in a time-dependent manner as compared with Lip-SODN and Lip alone groups (P< 0.05). Cell cycle distribution significantly changed in Lip-ASODN group, many cells have been blocked in G0/G1 phase (79.21%), while G2/M phase (4.92%) and S phase (15.87%) decreased. The apoptotic rate of Lip-ASODN group reached 33.18%, which was much higher than those of Lip-SODN and Lip alone groups (P< 0.05). CONCLUSION: Survivin ASODN can inhibit COC(1)/DDP cell proliferation, reduce the mRNA expression of survivin, and induce cell apoptosis.