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1.  Complete Genome Sequence of a Novel Mutant of Peste des Petits Ruminants Virus Obtained from China 
Genome Announcements  2015;3(1):e01504-14.
Here, we announce the complete genome sequence of a spontaneous mutant of peste des petits ruminants virus (PPRV), termed China/BJ/2014, suggesting that PPRV continues to evolve. This information is crucial for developing strategies for the efficient prevention and control of PPRV.
PMCID: PMC4333651  PMID: 25676751
2.  Structure of Influenza Virus N7: the Last Piece of the Neuraminidase “Jigsaw” Puzzle 
Journal of Virology  2014;88(16):9197-9207.
There are nine subtypes of influenza A virus neuraminidase (NA), N1 to N9. In addition, influenza B virus also contains NA, and there are two influenza virus NA-like molecules, N10 and N11, which were recently identified from bats. Crystal structures for all of these proteins have been solved, with the exception of N7, and there is no published report of N6, although a structure has been deposited in the Protein Data Bank. Here, we present the N7 and N6 structures at 2.1 Å and 1.8 Å, respectively. Structural comparison of all NA subtypes shows that both N7 and N6 highly resemble typical group 2 NA structures with some special characteristics, including an additional cavity adjacent to their active sites formed by novel 340-loop conformations. Comparative analysis also revealed new structural insights into the N-glycosylation, calcium binding, and second sialic acid binding site of influenza virus NA. This comprehensive study is critical for understanding the complexity of the most successful influenza drug target and for the structure-based design of novel influenza inhibitors.
IMPORTANCE Influenza viruses impose a great burden on society, by the human-adapted seasonal types as well as by variants that occasionally jump from the avian reservoir to infect humans. The surface glycoprotein neuraminidase (NA) is essential for the propagation of the virus and currently the most successfully drug-targeted molecule. Therefore, the structural and functional analysis of NA is critical for the prevention and control of influenza infections. There are nine subtypes of influenza A virus NA (N1 to N9). In addition, influenza B virus also contains NA, and there are two influenza NA-like molecules, N10 and N11, which were recently identified in bats. Crystal structures for all of these proteins have been solved and reported with the exception of N7 and N6. The structural analysis of influenza virus N7 and N6 presented in this study therefore completes the puzzle and adds to a comprehensive understanding of influenza virus NA.
PMCID: PMC4136277  PMID: 24899180
3.  An intestinal commensal symbiosis factor controls neuroinflammation via TLR2-mediated CD39 signaling 
Nature communications  2014;5:4432.
The mammalian immune system constitutively senses vast quantities of commensal bacteria and their products through pattern recognition receptors, yet excessive immune reactivity is prevented under homeostasis. Intestinal microbiome can influence host susceptibility to extra-intestine autoimmune disorders. Here we report that polysaccharide A (PSA), a symbiosis factor for human intestinal commensal Bacteroides fragilis, protects against central nervous system demyelination and inflammation during experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis, through toll-like receptor 2 (TLR2). TLR2 mediates tissue-specific expansion of a critical regulatory CD39+ CD4 T cell subset by PSA. Ablation of CD39 signaling abrogates PSA control of EAE manifestations and inflammatory cytokine responses. Further, CD39 confers immune-regulatory phenotypes to total CD4 T cells and Foxp3+ CD4 Tregs. Importantly, CD39-deficient CD4 T cells show an enhanced capability to drive EAE progression. Our results demonstrate the therapeutic potential and underlying mechanism by which an intestinal symbiont product modulates CNS-targeted demyelination.
PMCID: PMC4118494  PMID: 25043484
4.  A rice lectin receptor-like kinase that is involved in innate immune responses also contributes to seed germination 
The Plant Journal  2013;76(4):687-698.
Seed germination and innate immunity both have significant effects on plant life spans because they control the plant's entry into the ecosystem and provide defenses against various external stresses, respectively. Much ecological evidence has shown that seeds with high vigor are generally more tolerant of various environmental stimuli in the field than those with low vigor. However, there is little genetic evidence linking germination and immunity in plants. Here, we show that the rice lectin receptor-like kinase OslecRK contributes to both seed germination and plant innate immunity. We demonstrate that knocking down the OslecRK gene depresses the expression of α–amylase genes, reducing seed viability and thereby decreasing the rate of seed germination. Moreover, it also inhibits the expression of defense genes, and so reduces the resistance of rice plants to fungal and bacterial pathogens as well as herbivorous insects. Yeast two-hybrid and co-immunoprecipitation experiments revealed that OslecRK interacts with an actin-depolymerizing factor (ADF) in vivo via its kinase domain. Moreover, the rice adf mutant exhibited a reduced seed germination rate due to the suppression of α–amylase gene expression. This mutant also exhibited depressed immune responses and reduced resistance to biotic stresses. Our results thus provide direct genetic evidence for a common physiological pathway connecting germination and immunity in plants. They also partially explain the common observation that high-vigor seeds often perform well in the field. The dual effects of OslecRK may be indicative of progressive adaptive evolution in rice.
PMCID: PMC4285754  PMID: 24033867
rice; lectin receptor-like kinase; seed germination; innate immunity; pleiotropy; progressive fitness
5.  Burden of Disease Measured by Disability-Adjusted Life Years and a Disease Forecasting Time Series Model of Scrub Typhus in Laiwu, China 
Laiwu District is recognized as a hyper-endemic region for scrub typhus in Shandong Province, but the seriousness of this problem has been neglected in public health circles.
Methodology/Principal Findings
A disability-adjusted life years (DALYs) approach was adopted to measure the burden of scrub typhus in Laiwu, China during the period 2006 to 2012. A multiple seasonal autoregressive integrated moving average model (SARIMA) was used to identify the most suitable forecasting model for scrub typhus in Laiwu. Results showed that the disease burden of scrub typhus is increasing yearly in Laiwu, and which is higher in females than males. For both females and males, DALY rates were highest for the 60–69 age group. Of all the SARIMA models tested, the SARIMA(2,1,0)(0,1,0)12 model was the best fit for scrub typhus cases in Laiwu. Human infections occurred mainly in autumn with peaks in October.
Females, especially those of 60 to 69 years of age, were at highest risk of developing scrub typhus in Laiwu, China. The SARIMA (2,1,0)(0,1,0)12 model was the best fit forecasting model for scrub typhus in Laiwu, China. These data are useful for developing public health education and intervention programs to reduce disease.
Author Summary
Scrub typhus, also known as tsutsugamushi disease, is a zoonosis transmitted by chigger bites (larval trombiculid mites) and the pathogen Orientia tsutsugamushi (O. tsutsugamushi), a Gram-negative obligate intracellular bacterium. It is distributed widely in the Pacific regions of Asia, and the islands of the western Pacific and Indian Oceans. People with outdoor activities that involve contact with grasses or shrubs are at highest risk. Scrub typhus has existed in Southern China for thousands of years, but it has been noted to spread from the South to the North of China in recent decades. Though this research we studied the disease burden of scrub typhus with disability-adjusted life years (DALYs), and developed a forecasting time series model for human clinical disease in Laiwu, China. Results demonstrated that the disease burden of scrub typhus was increasing year by year in Laiwu, and it was higher in females than males. Moreover, DALY rates in females and males were highest for persons in the 60–69 years age group. Of all the seasonal autoregressive integrated moving average (SARIMA) models tested, the SARIMA(2,1,0)(0,1,0)12 model was the best fit for scrub typhus cases in Laiwu. The disease occurred mainly in autumn, with a peak in October.
PMCID: PMC4288724  PMID: 25569248
6.  Functional analysis of a survivin-like gene in Bombyx mori 
Cytotechnology  2013;66(1):181-191.
The survivin (svv) gene is a newly discovered member of the inhibitors of apoptosis gene family. In recent years, svv has been confirmed to have an anti-apoptosis function and to play a critical role in cell division. We identified a survivin-like gene in the silkworm, Bombyx mori (Bm-svv). In this study, to gain insight into its function, a baculovirus expression system was used to express the Bm-svv gene in insect cell lines. The recombinant viruses were then used as a vector to transform insect cells, and cell activity was determined using the Cell Counting Kit-8 (CCK-8), which is usually employed for detecting mammalian cell number. The results indicated that the Bm-svv gene plays a role in the cell growth arrest or apoptosis induced by viruses. Furthermore, the CCK-8 kit is effective in determining the activity of insect cells.
PMCID: PMC3886537  PMID: 23529562
IAP; Cell growth; AcNPV; BmNPV; Baculovirus; CCK-8
7.  B7-H1–expressing antigen-presenting cells mediate polarization of protumorigenic Th22 subsets 
The Journal of Clinical Investigation  2014;124(10):4657-4667.
Classical IL-22–producing T helper cells (Th22 cells) mediate inflammatory responses independently of IFN-γ and IL-17; however, nonclassical Th22 cells have been recently identified and coexpress IFN-γ and/or IL-17 along with IL-22. Little is known about how classical and nonclassical Th22 subsets in human diseases are regulated. Here, we used samples of human blood, normal and peritumoral liver, and hepatocellular carcinoma (HCC) to delineate the phenotype, distribution, generation, and functional relevance of various Th22 subsets. Three nonclassical Th22 subsets constituted the majority of all Th22 cells in human liver and HCC tissues, although the classical Th22 subset was predominant in blood. Monocytes activated by TLR2 and TLR4 agonists served as the antigen-presenting cells (APCs) that most efficiently triggered the expansion of nonclassical Th22 subsets from memory T cells and classical Th22 subsets from naive T cells. Moreover, B7-H1–expressing monocytes skewed Th22 polarization away from IFN-γ and toward IL-17 through interaction with programmed death 1 (PD-1), an effect that can create favorable conditions for in vivo aggressive cancer growth and angiogenesis. Our results provide insight into the selective modulation of Th22 subsets and suggest that strategies to influence functional activities of inflammatory cells may benefit anticancer therapy.
PMCID: PMC4191045  PMID: 25244097
8.  Synthesis and Antibacterial Evaluation of (S,Z)-4-methyl-2-(4-oxo-5-((5-substituted phenylfuran-2-yl) methylene)-2-thioxothiazolidin-3-yl)Pentanoic Acids 
The microbial resistance has become a global hazard with the irrational use of antibiotics. Infection of drug-resistant bacteria seriously threatens human health. Currently, there is an urgent need for the development of novel antimicrobial agents with new mechanisms and lower levels of toxicity. In this paper, a series of (S,Z)-4-methyl-2-(4-oxo-5-((5-substitutedphenylfuran-2-yl) methylene)-2-thioxothiazolidin-3-yl)pentanoic acids via a Knoevenagel condensation were synthesized and evaluated for their antibacterial activity in-vitro. The synthesized compounds were characterized by IR, 1H NMR and MS. The antibacterial test in-vitro showed that all of the synthesized compounds had good antibacterial activity against several Gram-positive bacteria (including multidrug-resistant clinical isolates) with minimum inhibitory concentration (MIC) values in the range of 2–4 µg/mL. Especially compounds 4c, 4d, 4e and 4f were the most potent, with MIC values of 2 µg/mL against four multidrug-resistant Gram-positive bacterial strains.
PMCID: PMC4277622  PMID: 25561915
Furan; Pentanoic acid; Antibacterial activity; Cytotoxicity; MRSA; QRSA
9.  Platelet Rich Plasma Clot Releasate Preconditioning Induced PI3K/AKT/NFκB Signaling Enhances Survival and Regenerative Function of Rat Bone Marrow Mesenchymal Stem Cells in Hostile Microenvironments 
Stem Cells and Development  2013;22(24):3236-3251.
Mesenchymal stem cells (MSCs) have been optimal targets in the development of cell based therapies, but their limited availability and high death rate after transplantation remains a concern in clinical applications. This study describes novel effects of platelet rich clot releasate (PRCR) on rat bone marrow-derived MSCs (BM-MSCs), with the former driving a gene program, which can reduce apoptosis and promote the regenerative function of the latter in hostile microenvironments through enhancement of paracrine/autocrine factors. By using reverse transcription–polymerase chain reaction, immunofluorescence and western blot analyses, we showed that PRCR preconditioning could alleviate the apoptosis of BM-MSCs under stress conditions induced by hydrogen peroxide (H2O2) and serum deprivation by enhancing expression of vascular endothelial growth factor and platelet-derived growth factor (PDGF) via stimulation of the platelet-derived growth factor receptor (PDGFR)/PI3K/AKT/NF-κB signaling pathways. Furthermore, the effects of PRCR preconditioned GFP-BM-MSCs subcutaneously transplanted into rats 6 h after wound surgery were examined by histological and other tests from days 0–22 after transplantation. Engraftment of the PRCR preconditioned BM-MSCs not only significantly attenuated apoptosis and wound size but also improved epithelization and blood vessel regeneration of skin via regulation of the wound microenvironment. Thus, preconditioning with PRCR, which reprograms BM-MSCs to tolerate hostile microenvironments and enhance regenerative function by increasing levels of paracrine factors through PDGFR-α/PI3K/AKT/NF-κB signaling pathways would be a safe method for boosting the effectiveness of transplantation therapy in the clinic.
PMCID: PMC3868358  PMID: 23885779
10.  Prevalence of potentially traumatic events, depression, alcohol use, and social network supports among Chinese migrants: an epidemiological study in Guangzhou, China 
European Journal of Psychotraumatology  2014;5:10.3402/ejpt.v5.26529.
Addressing the health needs of Chinese migrants is a critical public health concern. Epidemiological studies are needed to establish the prevalence of potentially traumatic events (PTEs) and common mental disorders among Chinese migrants and identify protective community and social resources.
Utilizing random household sampling, we are in the process of recruiting a representative sample of Chinese adults (N=1,000) in two districts home to a large number of internal migrants. Data are collected using face-to-face interviews and participant self-report methods. Chinese versions of the Life Events Checklist, Alcohol Use Disorders Identification Test, Patient Health Questionnaire and the Social Support Rating Scale measured exposure to PTEs, alcohol use disorder, depression, and social support networks.
Preliminary results indicate a high proportion (68%) of the sample was exposed directly or indirectly to at least one PTE. The most commonly reported events were transportation accidents (43%), natural disasters (39%), and physical assault (26%). A total of 17% of the sample reported drinking consistent with having an alcohol use disorder. Moderate or severe depression was reported by 9% of the sample. The majority (75%) reported having three or more people to rely on for support, and 41% reported active participation in civic groups. Despite these strengths, only half the sample reported having trust in their community.
Preliminary evidence from this population-level survey indicates high exposure to PTEs and a high potential burden of alcohol use disorders. The role of social networks will be explored as potentially useful for community-based intervention development.
PMCID: PMC4265129  PMID: 25511733
depression; alcohol abuse; social resources; migration; China
11.  Reduction of facial pigmentation of melasma by topical lignin peroxidase: A novel fast-acting skin-lightening agent 
The aim of the present study was to evaluate the efficacy and safety of lignin peroxidase (LIP) as a skin-lightening agent in patients with melasma. A self-controlled clinical study was performed in 31 women who had melasma on both sides of the face. This study involved 8 weeks of a full-face product treatment. The skin color was measured at days 0, 7, 28 and 56 using a chromameter on the forehead and cheeks. Standardized digital photographic images of each side of the face of all subjects were captured by a complexion analysis system. Clinical scores of the pigmentation were determined by two dermatologists. After using the LIP whitening lotion for 7 days, the luminance (L*) values of the melasma and the normal skin were significantly increased from baseline. The L* values continued to increase at days 28 and 56. The melasma area severity index (MASI) score was statistically decreased after 28 days of treatment. No treatment-related adverse events were observed. LIP whitening lotion was able to eliminate the skin pigmentation after 7 days of treatment, and provides a completely innovative approach to rapid skin lightening. The LIP whitening lotion exhibited good compatibility and was well tolerated.
PMCID: PMC4280934  PMID: 25574195
lignin peroxidase; melanin; melasma; skin lightening; emulsions; statistics
12.  Mapping the Cellular Response to Small Molecules Using Chemogenomic Fitness Signatures 
Science (New York, N.Y.)  2014;344(6180):208-211.
Genome-wide characterization of the in vivo cellular response to perturbation is fundamental to understanding how cells survive stress. Identifying the proteins and pathways perturbed by small molecules affects biology and medicine by revealing the mechanisms of drug action. We used a yeast chemogenomics platform that quantifies the requirement for each gene for resistance to a compound in vivo to profile 3250 small molecules in a systematic and unbiased manner. We identified 317 compounds that specifically perturb the function of 121 genes and characterized the mechanism of specific compounds. Global analysis revealed that the cellular response to small molecules is limited and described by a network of 45 major chemogenomic signatures. Our results provide a resource for the discovery of functional interactions among genes, chemicals, and biological processes.
PMCID: PMC4254748  PMID: 24723613
13.  CD39 Modulates Hematopoietic Stem Cell Recruitment and Promotes Liver Regeneration in Mice and Humans After Partial Hepatectomy 
Annals of surgery  2013;257(4):693-701.
To study molecular mechanisms involved in hematopoietic stem cell (HSC) mobilization after liver resection and determine impacts on liver regeneration.
Extracellular nucleotide-mediated cell signaling has been shown to boost liver regeneration. Ectonucleotidases of the CD39 family are expressed by bone marrow–derived cells, and purinergic mechanisms might also impact mobilization and functions of HSC after liver injury.
Partial hepatectomy was performed in C57BL/6 wild-type, Cd39 ectonucleotidase-null mice and in chimeric mice after transplantation of wild-type or Cd39-null bone marrow. Bone marrow–derived HSCs were purified by fluorescence-activated cell sorting and administered after hepatectomy. Chemotactic studies were performed to examine effects of purinergic receptor agonists and antagonists in vitro. Mobilization of human HSCs and expression of CD39 were examined and linked to the extent of resection and liver tests.
Subsets of HSCs expressing Cd39 are preferentially mobilized after partial hepatectomy. Chemotactic responses of HSCs are increased by CD39-dependent adenosine triphosphate hydrolysis and adenosine signaling via A2A receptors in vitro. Mobilized Cd39high HSCs boost liver regeneration, potentially limiting interleukin 1β signaling. In clinical studies, mobilized human HSCs also express CD39 at high levels. Mobilization of HSCs correlates directly with the restoration of liver volume and function after partial hepatectomy.
We demonstrate CD39 to be a novel HSC marker that defines a functionally distinct stem cell subset in mice and humans. HSCs are mobilized after liver resection, limit inflammation, and boost regeneration in a CD39-dependent manner. These observations have implications for monitoring and indicate future therapeutic avenues.
PMCID: PMC4243517  PMID: 23474584
CD133; CD39; liver regeneration; stem cells; vascular inflammation
14.  Δ9-THC-caused synaptic and memory impairments are mediated through COX-2 signaling 
Cell  2013;155(5):1154-1165.
Marijuana has been used for thousands of years as a treatment for medical conditions. However, untoward side effects limit its medical value. Here we show that synaptic and cognitive impairments following repeated exposure to Δ9-tetrahydrocannabinol (Δ9-THC) are associated with the induction of cyclooxygenase-2 (COX-2), an inducible enzyme that converts arachidonic acid to prostanoids, in the brain. COX-2 induction by Δ9-THC is mediated via CB1 receptor-coupled G-protein βγ subunits. Pharmacological or genetic inhibition of COX-2 blocks down-regulation and internalization of glutamate receptor subunits and alterations of the dendritic spine density of hippocampal neurons induced by repeated Δ9-THC exposures. Ablation of COX-2 also eliminates Δ9-THC-impaired hippocampal long-term synaptic plasticity, spatial, and fear memories. Importantly, the beneficial effects of decreasing β-amyloid plaques and neurodegeneration by Δ9-THC in Alzheimer’s disease animals are retained in the presence of COX-2 inhibition. These results suggest that the applicability of medical marijuana would be broadened by concurrent inhibition of COX-2.
PMCID: PMC3918429  PMID: 24267894
15.  MS2 Virus Inactivation by Atmospheric-Pressure Cold Plasma Using Different Gas Carriers and Power Levels 
In this study, airborne MS2 bacteriophages were exposed for subsecond time intervals to atmospheric-pressure cold plasma (APCP) produced using different power levels (20, 24, and 28 W) and gas carriers (ambient air, Ar-O2 [2%, vol/vol], and He-O2 [2%, vol/vol]). In addition, waterborne MS2 viruses were directly subjected to the APCP treatment for up to 3 min. MS2 viruses with and without the APCP exposure were examined by scanning electron microscopy (SEM), reverse transcription-PCR (RT-PCR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Viral inactivation was shown to exhibit linear relationships with the APCP generation power and exposure time (R2 > 0.95 for all energy levels tested) up to 95% inactivation (1.3-log reduction) after a subsecond airborne exposure at 28 W; about the same inactivation level was achieved for waterborne viruses with an exposure time of less than 1 min. A larger amount of reactive oxygen species (ROS), such as atomic oxygen, in APCP was detected for a higher generation power with Ar-O2 and He-O2 gas carriers. SEM images, SDS-PAGE, and agarose gel analysis of exposed waterborne viruses showed various levels of damage to both surface proteins and their related RNA genes after the APCP exposure, thus leading to the loss of their viability and infectivity.
PMCID: PMC4292470  PMID: 25416775
16.  Expressions of MUC1 and vascular endothelial growth factor mRNA in blood are biomarkers for predicting efficacy of gefitinib treatment in non-small cell lung cancer 
BMC Cancer  2014;14(1):848.
Gefitinib, an EGFR-tyrosine kinase inhibitor, significantly improve prognosis in patients with advanced non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the usefulness of MUC1 and vascular endothelial growth factor (VEGF) mRNA expression in peripheral blood as means of predicting benefit from gefitinib therapy in NSCLC patients.
MUC1 and VEGF mRNA expressions were detected in peripheral blood of 66 patients with advanced NSCLC before (B0) and 4 weeks after treatment (B4w) with gefitinib, using real-time quantitative-PCR assay. Correlations between blood MUC1 and VEGF mRNA expression at B0 and B4w and the response to gefitinib treatment and survival were analyzed.
Blood levels of MUC1 and VEGF mRNA at B0 and at B4w were significantly higher in patients with progressive disease than in those with partial response and stable disease. Furthermore, blood MUC1 and VEGF mRNA positivity at two time points were strongly associated with shorter progression-free survival (PFS) and overall survival (OS) (P = 0.005 and P = 0.008 at B0, and P < 0.001 and P = 0.001 at B4w, respectively, for MUC1; P = 0.004 and P = 0.009 at B0, and P = 0.001 and P < 0.001 at B4w, respectively, for VEGF). Multivariate analyses demonstrated that blood MUC1 and VEGF mRNA positivity at B0 and B4w were independent factors for predicting worse PFS and OS.
MUC1 and VEGF mRNA positivity in blood seem to be indicators of unfavorable response and poor PFS and OS in patients with advanced NSCLC treated with gefitinib and may be promising noninvasive and repeatable markers for predicting efficacy of gefitinib treatment.
PMCID: PMC4246503  PMID: 25410981
Non-small cell lung cancer; Gefitinib; MUC1; Vascular endothelial growth factor; Treatment response; Survival
17.  Seed Dormancy, Seedling Establishment and Dynamics of the Soil Seed Bank of Stipa bungeana (Poaceae) on the Loess Plateau of Northwestern China 
PLoS ONE  2014;9(11):e112579.
Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation of seeds over a range of temperatures in both light and dark. Seed germination was evaluated after mechanical removal of palea and lemma (hulls), chemical scarification and dry storage. Fresh and one-year-stored seeds were sown in the field, and seedling emergence was monitored weekly for 8 weeks. Furthermore, seeds were buried at different soil depths, and then retrieved every 1 or 2 months to determine seed dormancy and seed viability in the laboratory. Fresh seeds (caryopses enclosed by palea and lemma) had non-deep physiological dormancy. Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA3) and potassium nitrate (KNO3) significantly improved germination. Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%. Pretreatment of seeds with a 30% NaOH solution for 60 min increased germination from 25% to 82%. Speed of seedling emergence from fresh seeds was significantly lower than that of seeds stored for 1 year. However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm. Most fresh seeds of S. bungeana buried in the field in early July either had germinated or lost viability by September. All seeds buried at a depth of 5 cm had lost viability after 5 months, whereas 12% and 4% seeds of those sown on the soil surface were viable after 5 and 12 months, respectively.
PMCID: PMC4232413  PMID: 25396423
18.  Microbial Diversity of a Camembert-Type Cheese Using Freeze-Dried Tibetan Kefir Coculture as Starter Culture by Culture-Dependent and Culture-Independent Methods 
PLoS ONE  2014;9(10):e111648.
The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.
PMCID: PMC4216126  PMID: 25360757
19.  PI3K/AKT Pathway Involvement in the Osteogenic Effects of Osteoclast Culture Supernatants on Preosteoblast Cells 
Tissue Engineering. Part A  2013;19(19-20):2226-2232.
This study aimed to investigate the ability of osteoclasts during bone resorption activities to regulate the differentiation and calcification of osteoblast precursor cells. The bone resorption model was established using in vitro cortical bone slices and mouse RAW264.7 cells, which were differentiated into osteoclasts by stimulation with the receptor activator of nuclear factor-κB ligand and macrophage colony-stimulating factor. Tartrate-resistant acid phosphatase (TRAP) staining, reverse transcriptase–polymerase chain reaction (RT-PCR), and scanning electron microscopy (SEM) were used to detect osteoclast differentiation. The osteoblast precursor cell line MC3T3-E1 was cultured with the bone resorption supernatant (BRS). Involvement of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway in osteogenesis was evaluated by Western blotting, RT-PCR, and ELISA analysis of markers of the early (runt-related transcription factor-2 and alkaline phosphatase) and late (osteocalcin [OCN]) stages of osteogenesis, and Alizarin Red S staining of matrix mineralization. TRAP staining, RT-PCR, and SEM analysis demonstrated the successful establishment of the bone resorption model. Osteoclast BRS effectively increased the differentiation and calcification of MC3T3-E1 cells. Western blot analysis indicated that the BRS enhanced AKT and p-AKT expression levels in MC3T3-E1 cells. Following AKT2 knockdown and treatment with the PI3K/AKT pathway inhibitor LY294002, the expression of OCN in MC3T3-E1 cells was decreased (p<0.05), as was the calcification area (p<0.05). The data obtained in this study indicated that the osteoclast bone resorption medium promoted the differentiation and calcification of MC3T3-E1 cells and that the PI3K/AKT pathway played a role in this process.
PMCID: PMC3761438  PMID: 23617625
20.  Interleukin-27 acts on dendritic cells to suppress the T-cell response and autoimmunity by inducing the expression of ENTPD1 (CD39) 
Nature immunology  2013;14(10):1054-1063.
Dendritic cells (DCs) control the balance between effector and regulatory T cells in vivo. Hence, the study of DCs might identify mechanisms of disease pathogenesis and guide new therapeutic approaches for immune-mediated disorders. We found that IL-27 signaling in murine DCs limits the generation of effector TH1 and TH17 cells and the development of experimental autoimmune encephalomyelitis (EAE). The effects of IL-27 were mediated, at least partially, through the induction of the immunoregulatory molecule ENTPD1 (CD39) in DCs. IL-27-induced ENTPD1 decreased extracellular ATP levels, down-regulating nucleotide-dependent NLRP3 inflammasome activation. Finally, therapeutic vaccination with IL-27-conditioned DCs suppressed established relapsing-remitting EAE. Thus, IL-27 signaling in DCs limits pathogenic T cell responses and the development of autoimmunity.
PMCID: PMC3964005  PMID: 23995234
21.  Relationship between homocysteine level and diabetic retinopathy: a systematic review and meta-analysis 
Diagnostic Pathology  2014;9(1):167.
The relationship between homocysteine (Hcy) and diabetic retinopathy (DR) remains unclear to date. Therefore, a systematic review and meta-analysis was performed on the relationship between Hcy level and DR.
Studies were identified by searching PubMed, Embase, and Web of Science databases until 5 May, 2014.
A total of 31 studies involving 6,394 participants were included in the meta-analysis. After pooling the data from each included study, the blood Hcy concentration in the DR group was observed to be higher than that in the control group [WMD = 2.55; 95% confidence interval (CI), 1.70–3.40], and diabetes mellitus (DM) patients with hyperhomocysteinemia were at a risk for DR [odds ratio (OR) = 1.93; 95% CI, 1.46–2.53]. Considering the different DM types, hyperhomocysteinemia in T1DM (OR = 1.83, 95% CI, 1.28–2.62) was associated with DR rather than in T2DM (OR = 1.59, 95% CI, 0.72–3.51). Considerable statistical heterogeneity in the overall summary estimates was partly explained by the geographical differences.
Results from this current meta-analysis indicate that hyperhomocysteinemia is a risk factor for DR, especially proliferative DR. Differences between geographical regions were observed in the relationship between hyperhomocysteinemia with T1DM risk. Given the heterogeneous results, the relationship between high Hcy and DR needs further investigation.
Virtual Slides
The virtual slide(s) for this article can be found here:
PMCID: PMC4207897  PMID: 25257241
Hyperhomocysteinemia; Homocysteine; Diabetic retinopathy (DR)
22.  Toll-like receptor-4 pathway is required for the pathogenesis of human chronic endometritis 
Toll-like receptor (TLR) signal transduction is a central component of the primary innate immune response to pathogenic challenge. TLR4, a member of the TLR family, is highly expressed in the endometrial cells of the uterus and could thus be a key link between human chronic endometritis (CE) and the immune system. However, the exact biological function of TLR4 in human CE remains largely unexplored. The present study aimed to examine the role of TLR4 in human CE. A comprehensive expression and activation analysis of TLR4 in the endometrial cells of the uterus from patients with human CE (n=25) and normal endometrial (NE) tissue (n=15) was performed. Western blot analyses demonstrated that compared with NE, the protein expression TLR4 markedly increased in human CE. Endometrial tissue scrapings were also used for total RNA extraction and were transcribed and amplified by reverse transcription quantitative polymerase chain reaction. The results showed that significant upregulation of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), and downregulation of IL-10 mRNA was observed in CE compared with the NE group. Furthermore, the protein of the signaling adapter myeloid differentiation factor-88 and the accessory molecules (TNF receptor associated factor 6 and transforming growth factor-β-activated kinase 1) were also detected in all the assayed tissues. Of note, differential expression (CE versus NE) was observed by immunoblotting at each level of the nuclear factor-κB signaling cascade, including inhibitor κBα and P65 (all P<0.05). The altered TLR4 and its corresponding downstream signaling molecules in CE cells may be of relevance for the progression of the human CE. These findings indicate that the evaluation of expression patterns of TLR4 holds promise for the treatment of human CE.
PMCID: PMC4217777  PMID: 25371751
Toll-like receptor 4; chronic endometritis; inflammation; signaling pathway
23.  Laparoscopic left hepatectomy in swine: a safe and feasible technique 
Journal of Veterinary Science  2014;15(3):417-422.
A purely laparoscopic four-port approach was created for left hepatectomy in pigs. A polyethylene loop was placed on the left two hepatic lobes for traction and lift. Next, penetrating ligation of the lobes using of a double row of silk sutures was performed to control bleeding. A direct hepatic transection was completed using a monopolar hook electrode without meticulous dissection of the left hepatic vein. The raw surface of the liver was coagulated and sealed with fibrin glue. Lobes were retrieved through an enlarged portal. Laparoscopic hepatic lobectomy was completed in all pigs without the use of specialized instruments and with a mean operative time of 179 ± 9 min. No significant perioperative complications were observed. The average weight of each resected lobe was 180 ± 51 g. Complete blood count as well as serum organics and enzyme levels normalized after about 2 weeks. During necropsy, adhesion of the hepatic raw surface to the gastric wall and omentum were observed. No other abnormalities were identified. This minimally invasive left hepatectomy technique in swine could serve as a useful model for investigating liver diseases and regeneration, and offer preclinical information to improve hepatobiliary surgical procedures.
PMCID: PMC4178143  PMID: 24962406
hepatectomy; laparoscopy; left; pigs; technique
24.  Prolonged Neuroinflammation after Lipopolysaccharide Exposure in Aged Rats 
PLoS ONE  2014;9(8):e106331.
Inflammation is a hallmark of several disease states ranging from neurodegeneration to sepsis but is also implicated in physiological processes like ageing. Non-resolving inflammation and prolonged neuroinflammation are unclear processes implicated in several conditions, including ageing. In this study we studied the long-term effects of endotoxemia, as systemic lipopolysaccharide (LPS) injection, focusing on the role of astrocyte activation and cytokine release in the brain of aged rats. A single dose of LPS (2 mg/kg) or 0.9% saline was injected intraperitoneally in aged rats. Levels of pro-inflammatory cytokines (TNFα and IL-1β) and NF-κB p65 activation were measured systemically and in hippocampal tissue. Astrocytes and cytokines release in the CNS were detected via double immunofluorescence staining at different time-points up to day 30. Serum levels of TNFα and IL-1β were significantly increased acutely after 30 minutes (p<0.001) and up to 6 hours (p<0.001) following LPS-injection. Centrally, LPS-treated rats showed up-regulated mRNA expression and protein levels of pro-inflammatory cytokines in the hippocampus. These changes associated with astrogliosis in the hippocampus dentate gyrus (DG), IL-1β immunoreactivity and elevated NF-κB p65 expression up to day 30 post LPS exposure. Overall, these data demonstrate that LPS induces prolonged neuroinflammation and astrocyte activation in the hippocampus of aged rats. Hippocampal NF-κB p65 and excessive astrocytes-derived IL-1β release may play a pivotal role in regulating long-lasting neuroinflammation.
PMCID: PMC4149545  PMID: 25170959
25.  Spontaneous Development of IgM Anti-Cocaine Antibodies in Habitual Cocaine Users: Effect on IgG Antibody Responses to a Cocaine Cholera Toxin B Conjugate Vaccine 
Background and Objectives
In cocaine vaccine studies, only a minority of subjects made strong antibody responses. To investigate this issue, IgG and IgM antibody responses to cocaine and to cholera toxin B (CTB—the carrier protein used to enhance immune responses to cocaine) were measured in sera from the 55 actively vaccinated subjects in a Phase IIb randomized double-blind placebo-controlled trial (TA-CD 109).
Isotype specific ELISAs were used to measure IgG and IgM anti-cocaine and anti-CTB antibody in serial samples collected prior to and at intervals after immunization. We assessed IgG anti-cocaine responses of patients with pre-vaccination IgM anti-cocaine antibodies. Competitive inhibition ELISA was used to evaluate antibody specificity.
Results and Conclusions
Before immunization, 36/55 subjects had detectable IgM antibodies to cocaine, and 9 had IgM levels above the 95% confidence limit of 11 µg/ml. These nine had significantly reduced peak IgG anti-cocaine responses at 16 weeks, and all were below the concentration (40 µg/ml) considered necessary to discourage recreational cocaine use. The IgG anti-CTB responses of these same subjects were also reduced.
Scientific Significance
Subjects who develop an IgM antibody response to cocaine in the course of repeated recreational exposure to this drug are significantly less likely to produce high levels of IgG antibodies from the cocaine conjugate vaccine. The failure may be due to recreational cocaine exposure induction of a type 2 T-cell independent immune response. Such individuals will require improved vaccines and are poor candidates for the currently available vaccine.
PMCID: PMC4143984  PMID: 23414504

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