SARF: Aliasing Relation-Assisted Self-Supervised Learning for Few-Shot Relation Reasoning.

Few-shot relation reasoning on knowledge graphs (FS-KGR) is an important and practical problem that aims to infer long-tail relations and has drawn increasing attention these years. Among all the proposed methods, self-supervised learning (SSL) methods, which effectively extract the hidden essential inductive patterns relying only on the support sets, have achieved promising performance. However, the existing SSL methods simply cut down connections between high-frequency and long-tail relations, which ignores the fact, i.e., the two kinds of information could be highly related to each other. Specifically, we observe that relations with similar contextual meanings, called aliasing relations (ARs), may have similar attributes. In other words, the ARs of the target long-tail relation could be in high-frequency, and leveraging such attributes can largely improve the reasoning performance. Based on the interesting observation above, we proposed a novel Self-supervised learning model by leveraging Aliasing Relations to assist FS-KGR, termed . Specifically, we propose a graph neural network (GNN)-based AR-assist module to encode the ARs. Besides, we further provide two fusion strategies, i.e., simple summation and learnable fusion, to fuse the generated representations, which contain extra abundant information underlying the ARs, into the self-supervised reasoning backbone for performance enhancement. Extensive experiments on three few-shot benchmarks demonstrate that achieves state-of-the-art (SOTA) performance compared with other methods in most cases.

Nanopore targeted sequencing-based diagnosis of central nervous system infections in HIV-infected patients.

BACKGROUND: Early and accurate etiological diagnosis is very important for improving the prognosis of central nervous system (CNS) infections in human immunodeficiency virus (HIV)-infected patients. The goal is not easily achieved by conventional microbiological tests. We developed a nanopore targeted sequencing (NTS) platform and evaluated the diagnostic performance for CNS infections in HIV-infected patients, with special focus on cryptococcal meningitis (CM). We compared the CM diagnostic performance of NTS with conventional methods and cryptococcal polymerase chain reaction (PCR). METHODS: This study included 57 hospitalized HIV-infected patients with suspected CNS infections from September 2018 to March 2022. The diagnosis established during hospitalization includes 27 cases of CM, 13 CNS tuberculosis, 5 toxoplasma encephalitis, 2 cytomegalovirus (CMV) encephalitis and 1 Varicella-zoster virus (VZV) encephalitis. The 2 cases of CMV encephalitis also have co-existing CM. Target-specific PCR amplification was used to enrich pathogen sequences before nanopore sequencing. NTS was performed on stored cerebrospinal fluid (CSF) samples and the results were compared with the diagnosis during hospitalization. RESULTS: 53 (93.0%) of the patients were male. The median CD4 cell count was 25.0 (IQR: 14.0-63.0) cells/uL. The sensitivities of CSF culture, India ink staining, cryptococcal PCR and NTS for CM were 70.4% (95%CI: 51.5 - 84.1%), 76.0% (95%CI: 56.6 - 88.5%), 77.8% (59.2 - 89.4%) and 85.2% (95%CI: 67.5 - 94.1%), respectively. All those methods had 100% specificity for CM. Our NTS platform could identify Cryptococcus at species level. Moreover, NTS was also able to identify all the 5 cases of toxoplasma encephalitis, 2 cases of CMV encephalitis and 1 VZV encephalitis. However, only 1 of 13 CNS tuberculosis cases was diagnosed by NTS, and so did Xpert MTB/RIF assay. CONCLUSIONS: NTS has a good diagnostic performance for CM in HIV-infected patients and may have the ability of simultaneously detecting other pathogens, including mixed infections. With continuing improving of the NTS platform, it may be a promising alterative microbiological test for assisting with the diagnosis of CNS infections.

Simple Contrastive Graph Clustering.

Contrastive learning has recently attracted plenty of attention in deep graph clustering due to its promising performance. However, complicated data augmentations and time-consuming graph convolutional operations undermine the efficiency of these methods. To solve this problem, we propose a simple contrastive graph clustering (SCGC) algorithm to improve the existing methods from the perspectives of network architecture, data augmentation, and objective function. As to the architecture, our network includes two main parts, that is, preprocessing and network backbone. A simple low-pass denoising operation conducts neighbor information aggregation as an independent preprocessing, and only two multilayer perceptrons (MLPs) are included as the backbone. For data augmentation, instead of introducing complex operations over graphs, we construct two augmented views of the same vertex by designing parameter unshared Siamese encoders and perturbing the node embeddings directly. Finally, as to the objective function, to further improve the clustering performance, a novel cross-view structural consistency objective function is designed to enhance the discriminative capability of the learned network. Extensive experimental results on seven benchmark datasets validate our proposed algorithm's effectiveness and superiority. Significantly, our algorithm outperforms the recent contrastive deep clustering competitors with at least seven times speedup on average. The code of SCGC is released at SCGC. Besides, we share a collection of deep graph clustering, including papers, codes, and datasets at ADGC.

Task-Related Saliency for Few-Shot Image Classification.

A weakness of the existing metric-based few-shot classification method is that task-unrelated objects or backgrounds may mislead the model since the small number of samples in the support set is insufficient to reveal the task-related targets. An essential cue of human wisdom in the few-shot classification task is that they can recognize the task-related targets by a glimpse of support images without being distracted by task-unrelated things. Thus, we propose to explicitly learn task-related saliency features and make use of them in the metric-based few-shot learning schema. We divide the tackling of the task into three phases, namely, the modeling, the analyzing, and the matching. In the modeling phase, we introduce a saliency sensitive module (SSM), which is an inexact supervision task jointly trained with a standard multiclass classification task. SSM not only enhances the fine-grained representation of feature embedding but also can locate the task-related saliency features. Meanwhile, we propose a self-training-based task-related saliency network (TRSN) which is a lightweight network to distill task-related salience produced by SSM. In the analyzing phase, we freeze TRSN and use it to handle novel tasks. TRSN extracts task-relevant features while suppressing the disturbing task-unrelated features. We, therefore, can discriminate samples accurately in the matching phase by strengthening the task-related features. We conduct extensive experiments on five-way 1-shot and 5-shot settings to evaluate the proposed method. Results show that our method achieves a consistent performance gain on benchmarks and achieves the state-of-the-art.

High Cytomegalovirus Viral Load Is Associated With 182-Day All-Cause Mortality in Hospitalized People With Human Immunodeficiency Virus.

BACKGROUND: Cytomegalovirus (CMV) infection is associated with increased mortality in persons with HIV (PWH). It is less clear whether CMV infection is still associated with mortality when routinely screened and adequately treated. METHODS: This retrospective cohort study recruited 1003 hospitalized adults with HIV with CD4 cell counts <200 cells/µL from May 2017 to June 2021. Blood CMV DNA was routinely measured and CMV DNAemia was treated if end-organ disease occurred. CMV viral load was categorized into below the limit of quantification (BLQ; <500 IU/mL), low viral load (LVL; 500-10 000 IU/mL), and high viral load (HVL; ≥10 000 IU/mL) groups. We compared the 182-day all-cause mortality among different groups. RESULTS: The median (IQR) CD4 cell count of patients was 33 (13-84) cells/µL. The prevalence of CMV DNAemia was 39.8% (95% CI: 36.7-42.9%) and was significantly associated with CD4 cell count. The 182-day all-cause mortality was 9.9% (95% CI: 8.0-11.7%). Univariable analysis showed that, compared with BLQ, LVL and HVL were associated with 1.73-fold and 3.81-fold increased risks of mortality, respectively (P = .032 and P < .001). After adjustment for predefined confounding factors, HVL but not LVL was still associated with increased risk of mortality (adjusted hazard ratio: 2.63; 95% CI: 1.61-4.29; P < .001). However, for patients on effective antiretroviral therapy, the impact of HVL on 182-day mortality was not significant (P = .713). CONCLUSIONS: High CMV viral load in hospitalized PWH was associated with higher mortality, even when identified early by screening. Optimalization of the management for those patients needs to be explored in future studies.

Metagenomic next-generation sequencing for identification of central nervous system pathogens in HIV-infected patients.

Although considerable interest in metagenomic next-generation sequencing (mNGS) has been attracted in recent years, limited data are available regarding the performance of mNGS in HIV-associated central nervous system (CNS) infection. Here, we conducted a retrospectively analyzing of the cerebrospinal fluid (CSF) mNGS reports and other clinical data from 80 HIV-infected patients admitted to the Second Hospital of Nanjing, China from March, 2018 to March, 2022. In our study, CSF mNGS reported negative result, mono-infection, and mixed infection in 8.8, 36.2, and 55% of the patients, respectively. Epstein-Barr virus (EBV), positive in 52.5% of samples, was the most commonly reported pathogen, followed by cytomegalovirus (CMV), John Cunningham virus (JCV), torque teno virus (TTV), cryptococcus neoformans (CN), toxoplasma Gondii (TE), and mycobacterium tuberculosis (MTB). 76.2% of the EBV identification and 54.2% of the CMV identification were not considered clinically important, and relative less sequence reads were reported in the clinical unimportant identifications. The clinical importance of the presence of TTV in CSF was not clear. Detection of JCV, CN, or TE was 100% suggestive of specific CNS infection, however, 60% of the MTB reports were considered contamination. Moreover, of the 44 (55%) mixed infections reported by mNGS, only 4 (5%) were considered clinical important, and mNGS failed to identify one mixed infection. Additionally, except for MTB, CSF mNGS tended to have high sensitivity to identify the above-mentioned pathogens (almost with 100% sensitivity). Even all the diagnostic strategies were evaluated, the cause of neurological symptoms remained undetermined in 6 (7.5%) patients. Overall, our results suggest that mNGS is a very sensitive tool for detecting common opportunistic CNS pathogen in HIV-infected patients, although its performance in CNS tuberculosis is unsatisfactory. EBV and CMV are commonly detected by CSF mNGS, however, the threshold of a clinical important detection remains to be defined.

Interpolation-Based Contrastive Learning for Few-Label Semi-Supervised Learning.

Semi-supervised learning (SSL) has long been proved to be an effective technique to construct powerful models with limited labels. In the existing literature, consistency regularization-based methods, which force the perturbed samples to have similar predictions with the original ones have attracted much attention for their promising accuracy. However, we observe that the performance of such methods decreases drastically when the labels get extremely limited, e.g., 2 or 3 labels for each category. Our empirical study finds that the main problem lies with the drift of semantic information in the procedure of data augmentation. The problem can be alleviated when enough supervision is provided. However, when little guidance is available, the incorrect regularization would mislead the network and undermine the performance of the algorithm. To tackle the problem, we: 1) propose an interpolation-based method to construct more reliable positive sample pairs and 2) design a novel contrastive loss to guide the embedding of the learned network to change linearly between samples so as to improve the discriminative capability of the network by enlarging the margin decision boundaries. Since no destructive regularization is introduced, the performance of our proposed algorithm is largely improved. Specifically, the proposed algorithm outperforms the second best algorithm (Comatch) with 5.3% by achieving 88.73% classification accuracy when only two labels are available for each class on the CIFAR-10 dataset. Moreover, we further prove the generality of the proposed method by improving the performance of the existing state-of-the-art algorithms considerably with our proposed strategy. The corresponding code is available at https://github.com/xihongyang1999/ICL_SSL.

Halophilic bacteria as starter cultures: A new strategy to accelerate fermentation and enhance flavor of shrimp paste.

Retaining the traditional flavor while shortening the fermentation cycle is the current research focus for shrimp paste fermentation technology. The present study investigated the effect of combined use of halophilic bacteria as starters on the sensory and flavor characteristics of rapidly fermented shrimp paste. Sensory evaluation indicated that the starter-inoculated samples had high texture, appearance, and overall quality scores. Headspace gas chromatography-ion mobility spectrometry/mass spectrometry (HS-GC-IMS/MS) identified 95 volatile compounds, the fingerprint profiles of the starter-inoculated samples were similar to those of the traditional sample. Notably, the content of benzaldehyde, phenylethylaldehyde, and 3-methylbutyraldehyde increased significantly in the starter-inoculated samples (p < 0.05), which may provide an intense malt, caramel, and pleasant odor. Although the content of certain flavor substances in the starter-inoculated samples was lower than those of traditional sample, the use significantly reduced the fermentation time and mimicked the flavor profile of traditional shrimp paste to some extent.

Identification of novel paralytic shellfish toxin binding protein via homology modeling and molecular docking.

A paralytic shellfish toxin binding protein (PST-BP) was extracted and purified from the viscera of oyster (Crassostrea hongkongensis) that accumulates paralytic shellfish toxin (PST), and the amino acid sequence of the protein was detected via HPLC-MS-MS. The structure of the PST-BP was built by homology modeling, and the interaction between PST and PST-BP was studied using molecular docking. The results showed that the purity of PST-BP was more than 99.8% after the purification. The PST-BP carried a molecular weight of 33.5 kDa and sequence alignment revealed its high sequence similarities with glyceraldehyde-3-phosphate-dehydrogenase (GAPDH). It has been shown that 99.9% of the amino acid residues in the PST-BP homology model are within a reasonable range, which exceeds the 90% threshold requirement for residuals in high-quality model structures. The molecular docking results revealed that Arg, Asp, Lys, Ala, Ser, Gln, Gly, Trp, Asn, Met, and Pro were identified as the major interacting amino acids residues between PST-BP and PST.

Complete genome sequence of Pseudoalteromonas sp. Xi13 capable of degrading κ-selenocarrageenan isolated from the floating ice of Southern Ocean.

κ-Selenocarrageenan, a type of selenized carrageenan polysaccharide, can be degraded by bacteria into oligosaccharides, which has a lower molecular weight and a higher bioavailability. However, research on the microbial degradation of κ-selenocarrageenan is less. In this article, we show that Pseudoalteromonas sp. Xi13, a possibly novel Antarctic bacterium isolated from the floating ice of Southern Ocean, can degrade κ-selenocarrageenan into selenium-oligosaccharides. To gain insights into these biological activities, this bacterium was focused on screening, identification and optimization of submerged fermentation conditions by single-factor experiment. Furthermore, Selenium-oligosaccharides, mainly disaccharides and tetrasaccharides, had a certain inhibitory effect on HeLa cervical cancer cells. Whole genome sequencing and data analysis revealed a plethora of glycoside hydrolase might be involved in κ-selenocarrageenan degradation simultaneously. All told, the recent analysis of above experiment may provide a detailed insight into the characterization, function and catalytic mechanism of Pse sp. Xi13.

Extraction of Chitin From Shrimp Shell by Successive Two-Step Fermentation of Exiguobacterium profundum and Lactobacillus acidophilus.

As an environmentally friendly and efficient method, successive two-step fermentation has been applied for extracting chitin from shrimp shells. To screen out the microorganisms for fermentation, a protease-producing strain, Exiguobacterium profundum, and a lactic acid-producing strain, Lactobacillus acidophilus, were isolated from the traditional fermented shrimp paste. Chitin was extracted by successive two-step fermentation with these two strains, and 85.9 ± 1.2% of protein and 95 ± 3% of minerals were removed. The recovery and yield of chitin were 47.82 and 16.32%, respectively. Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy (SEM) were used to characterize the chitin. The crystallinity index was 54.37%, and the degree of deacetylation was 3.67%, which was lower than that of chitin extracted by the chemical method. These results indicated that successive two-step fermentation using these two bacterial strains could be applied to extract chitin. This work provides a suitable strategy for developing an effective method to extract chitin by microbial fermentation.

Orally Administered DHA-Enriched Phospholipids and DHA-Enriched Triglyceride Relieve Oxidative Stress, Improve Intestinal Barrier, Modulate Inflammatory Cytokine and Gut Microbiota, and Meliorate Inflammatory Responses in the Brain in Dextran Sodium Sulfate Induced Colitis in Mice.

SCOPE: Studies based on DHA/EPA supplementation in animal models of inflammatory bowel disease (IBD) reveal controversial results. It is speculated that different forms of DHA may explain the controversial results. Therefore, the effects of DHA-enriched phospholipids (DHA-PL) and DHA-enriched triglyceride (DHA-TG) on IBD are compared. METHODS AND RESULTS: Male C57BL6/J mice are given DHA-PL and DHA-TG for 14 consecutive days, and receive ad libitum a 3.0% dextran sodium sulfate solution on the eighth day to establish IBD model. The results show that both DHA-PL and DHA-TG can reverse the colitis pathological process by decreasing the disease activity indexes (DAI), raising the colon length, suppressing the intestinal permeability, suppressing the oxidative stress, down-regulating pro-inflammatory factors, up-regulating anti-inflammatory factor in colon tissues. DHA-PL and DHA-TG also regulate the composition of gut microbiota via decreasing of the abundance Bacteroidetes and Firmicutes, and DHA-TG increases the abundance of Odoribacter. Importantly, DHA-PL and DHA-TG obviously attenuate the activation of microglia. CONCLUSIONS: DHA-PL shows outstanding advantages in regulating oxidative stress, inflammatory responses, and intestinal barrier permeability. The current research indicates that the existence of DHA affects the improvement, DHA in phospholipid form could be a more effective choice for nutritional intervention to prevent and treat colitis.

Effect of carboxymethyl chitosan on the detoxification and biotransformation of paralytic shellfish toxins in oyster Ostrea rivularis.

Economic bivalve ingested toxic algae causes frequent human poisoning events. To explore new compounds that can accelerate the depuration of toxins in shellfish, we investigated the detoxification of the paralytic shellfish toxins (PSTs) and the biotransformation pathway of PSTs during detoxification by the application of three treatments to a toxic bloom, Alexandrium minutum (A. minutum). The detoxification effect of Platymonas subcordiformis (PS) mixed with carboxymethyl chitosan (CMC) group is significantly better than the starving group in each oyster tissues. The toxicity of viscera which occupied 78.95% of total toxicity reduced to 155 MU/100g after 13 days' depuration experiment. And adding CMC could significantly achieve rapid detoxification and effectively reduce the STX to 0.07 µmol/100 g in viscera. Meanwhile, PSTs underwent biotransformation during the depuration process, which mainly manifested as GTX1/4→GTX2/3→STX, GTX2→dcGTX2. This study explored a new strategy for toxin depuration in shellfish.

Saccharina japonica Ethanol Extract Ameliorates Depression/Anxiety-Like Behavior by Inhibiting Inflammation, Oxidative Stress, and Apoptosis in Dextran Sodium Sulfate Induced Ulcerative Colitis Mice.

Saccharina japonica is a common marine vegetable in East Asian markets and has a variety of health benefits. This study was focused on the anti-depressant/anxiety effects of Saccharina japonica ethanol extract (SJE) on dextran sodium sulfate (DSS)-induced mice and its potential mechanism in their brain. Male C57BL/6 mice were treated with mesalazine and various doses of SJE (1, 2, and 4 g/kg body weight) for 2 weeks, followed by DSS treatment at the second week. The DSS-induced mice showed depression/anxiety-like behavior, which included shorter path length in the open field test and longer immobility time in the tail suspension test. L-SJE alleviated the depression-like behaviors. In the DSS-induced mice, reduced synaptic plasticity activated microglia, increased proinflammatory cytokines, decreased anti-inflammatory cytokine, and increased expression levels of Toll-like receptors-4, nuclear factor kappa-B, NOD-like receptors 3, apoptosis-associated speck-like protein, and Caspase-1 were observed, most of which were alleviated by SJE treatment. Furthermore, all the SJE groups could significantly enhance superoxide dismutase activity, while the L-SJE treatment decreased the contents of malondialdehyde, and the H-SJE treatment inhibited apoptosis. All these results showed that the SJE might serve as a nutritional agent for protecting the brain in ulcerative colitis mice.

Effect of the structural characterization of the fungal polysaccharides on their immunomodulatory activity.

The immunomodulatory effects of the four extracellular polysaccharides, namely WPA, WPB, AP2A, and TP1A, which were isolated from the fermented broth of Aspergillus aculeatus, A. terreus and Trichoderma sp. KK19L1, were investigated in vitro. WPA, WPB, AP2A, and TP1A were not toxic to RAW264.7 cells. These polysaccharides enhanced cell viability. WPA, WPB, AP2A, and TP1A showed increased immunomodulatory effect by strengthening the phagocytic activity and enhancing the release of NO, TNF-α and IL-6 from RAW264.7 cells. WPA, WPB, AP2A, and TP1A exhibited different immunomodulatory activity in vitro due to their different structural characterizations, and their immunoregulatory effects decreased successively in the following order: WPA, WPB, AP2A, and TP1A. The extracellular polysaccharides WPA, WPB, AP2A, and TP1A had potent immunomodulatory effects and could be used as potential immunomodulatory agents in the fields of functional food and medicine.

Biocompatibility of Alexandrium minutum in the growth and paralytic shellfish toxins production under five cultivation methods.

This study evaluated the performance of an easy-cultivation device for the mass culture of Alexandrium minutum (A. minutum), a dinoflagellate that produces paralytic shellfish toxins (PSTs). Five culture conditions including three different sizes of containers (250 mL conical flask, 500 mL beaker, and 20 L jar) in two different environments (out-incubator and incubator) were compared in terms of growth and PSTs production. Compared with the incubator environment, the out-incubator environment had more fluctuations in temperature and light intensity. Results showed that the cell densities of A. minutum increased in all groups, especially in the conical flask (I, out-incubator, 6.29×106 cells/mL) and the beaker (IV, incubator, 7.28×106 cells/mL). When cultured in the 20 L jar under out-incubator condition, the algae had the lowest cell density (2.82×106 cells/mL) but the highest toxicity (93.42 ± 2.55×10-6 MU/cell). The negative correlation between average growth rate and single-cell toxicity could be explained by biocompatibility, thereby indicating that the low growth rate led to high toxicity. HPLC-FLD showed that the cellular toxicity increased due to the quantitative increase in GTX1/4, which are the more toxic derivatives. The PSTs types consistently contained GTX1/4 and GTX2/3. The differences in algae growth and toxin-production could be due to changes in bacteria (out-incubator) and CO2 (incubator) with vessel size. The effects of environmental factors on algae are strain specific. The out-incubator device can be applied for large-scale cultivation of A. minutum considering the algae density and toxin-producing ability.

Lightweight aggregate obtained from municipal solid waste incineration bottom ash sludge (MSWI-BAS) and its characteristics affected by single factor of sintering mechanism.

To solve the disposal problem of municipal solid waste incineration bottom ash sludge (MSWI-BAS), using it as the main raw material to prepare lightweight aggregates (LWA) for resource utilization. Sintering is an important process to achieve the desired microstructure and material properties. This paper investigates the characteristics of LWA affected by single factor of sintering mechanism (sintering temperature, heating rate and soaking time). Results show that sintering temperature increased from 1130°C to 1160°C caused high-density microstructure materials gradually formed in LWA, leading to particle strength increased from 0.1 MPa to 3.64 MPa, particle density showed an overall upward trend, reaching a maximum of 916 Kg/m3 at 1160°C, and 1 h water absorption reduced from 68% to 25%. The heating rate of 15 K/min was beneficial to the formation of dense phase structure which could increase the particle strength, and the water absorption rate reached the lowest at this time, while the particle density was less affected by heating rate. When soaking time extended from 5 min to 20 min, particle strength and compressive density were gradually increased, and 1 h water absorption showed an overall downward trend, indicating that a longer soaking time was not conducive to the retention of pores. This study demonstrates that the utilization of MSWI-BAS to make high-performance LWA is feasible, along with the preferable environmental and economic benefits.Implications: MSWI-BAS were selected to produce lightweight aggregate (LWA), so that the sludge disposal problem is reduced. The effects of sintering temperature, heating rate and soaking time on the characteristics of LWA were investigated. Compact glass structures are formed at 1150°C and 1160°C which greatly improve the strength. The heating rate has little influence on the physical properties of LWA products. The particle density of LWA increases after the sintering soaking time reaches 15 minutes.

Characterization of the complete mitochondrial genome of the Pohlia nutans M211 from Antarctica.

The complete mitochondrial genome of Pohlia nutans M211, sequenced using Illumina NovaSeq PE150, was 99864 bp in length. It encoded 65 genes, comprising 38 protein-coding genes, 24 tRNA genes and 3 ribosomal RNA genes. For these 38 PCGs, the most common start codon was ATG and the most common termination codon was TAA. The total GC content was 36.91% while the composition of A + T was 60.39%. Phylogenomic analysis indicated that P. nutans M211 was closely related to Mielichhoferia elongate.

Development and properties of new kojic acid and chitosan composite biodegradable films for active packaging materials.

Chitosan and kojic acid composite films (CHn-KAm) utilizing three chitosan with differing molecular weights and kojic acid in different ratios were investigated. Results showed that chitosan with higher molecular weights presented higher viscosity, mechanical properties and lower water vapor permeability. Furthermore, kojic acid addition further significantly decreased apparent viscosity, water content, water vapor permeability as well as increasing the antibacterial activity of the films. Increasing the kojic acid concentration resulted in increased levels of a*, b*, ΔE*, opacity values and a decreased L* value, as compared to chitosan films. The mechanical properties of CHn-KAm films increased significantly with kojic acid addition into chitosan. FTIR spectral analyses revealed a strong interaction in the film matrix consistent with composite film mechanical and physical properties. The CHn-KAm films showed significant antibacterial effectiveness. The results suggested that the use of chitosan with a higher molecular weight as CHn-KAm films is expected to be a promising material for food packaging.

Structural characterization of arabinogalactan extracted from Ixeris chinensis (Thunb.) Nakai and its immunomodulatory effect on RAW264.7 macrophages.

An arabinogalactan (ICPA) was isolated from the water extract of Ixeris chinensis (Thunb.) Nakai. ICPA was mainly composed of galactose and arabinose with minor amount of glucose. The molecular weight of ICPA was 58.1 kDa. Structural analysis by methylation and NMR spectroscopy indicated that ICPA contained α-D-Glcp(1→, →5)-α-L-Araf(1→, ß-D-Galf(1→, →3)-ß-D-Galf(1→, ß-D-Galp(1→, →6)-ß-D-Galp(1→, and â†’ 3,6)-ß-D-Galp(1→, and that the molar ratio of the sugar residues was about 0.1:1.0:0.1:0.2:1.1:1.0:1.3, respectively. The immunomodulatory activity on RAW264.7 cells was measured in vitro. ICPA stimulated RAW 264.7 cell proliferation at 25-400 µg/mL in a dose-dependent manner. ICPA also enhanced phagocytosis, and the secretion of NO, TNF-α, and IL-6 by the cells. The results suggested the potential utilization of ICPA as an immunomodulatory agent.