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1.  Antigenic Divergence of Bordetella pertussis Isolates in Taiwan 
Journal of Clinical Microbiology  2005;43(11):5457-5461.
In recent studies, antigenic divergence has been observed in Bordetella pertussis circulating isolates. We collected 80 Bordetella pertussis isolates in Taiwan from 1998 to 2004 and analyzed them using a combination of pulsed-field gel electrophoresis (PFGE) and sequencing of the ptxS1 and prn genes. The incidence of pertussis increases every 3 years, and most of the isolates prevalent since 1998 have expressed nonvaccine ptxS1A and prn2 alleles. Through PFGE analysis, all isolates could be classified into four major groups, and the incidence of these groups exhibited a correlation with the prn allele expressed by the isolates. We found that PFGE is more discriminative than gene sequencing, since it could divide the isolates expressing the prn2 allele into two groups: one group circulating from 1998 to 2001 and another group circulating from 2001 to 2004. The transition between the two groups in 2000 coincided with an outbreak of 326 cases. This research indicates that the antigenic divergence of B. pertussis circulating isolates has evolved over time in Taiwan. Such information will have implications for vaccine policy in Taiwan.
doi:10.1128/JCM.43.11.5457-5461.2005
PMCID: PMC1287815  PMID: 16272470
2.  Posaconazole Exhibits In Vitro and In Vivo Synergistic Antifungal Activity with Caspofungin or FK506 against Candida albicans 
PLoS ONE  2013;8(3):e57672.
The object of this study was to test whether posaconazole, a broad-spectrum antifungal agent inhibiting ergosterol biosynthesis, exhibits synergy with the β-1,3 glucan synthase inhibitor caspofungin or the calcineurin inhibitor FK506 against the human fungal pathogen Candida albicans. Although current drug treatments for Candida infection are often efficacious, the available antifungal armamentarium may not be keeping pace with the increasing incidence of drug resistant strains. The development of drug combinations or novel antifungal drugs to address emerging drug resistance is therefore of general importance. Combination drug therapies are employed to treat patients with HIV, cancer, or tuberculosis, and has considerable promise in the treatment of fungal infections like cryptococcal meningitis and C. albicans infections. Our studies reported here demonstrate that posaconazole exhibits in vitro synergy with caspofungin or FK506 against drug susceptible or resistant C. albicans strains. Furthermore, these combinations also show in vivo synergy against C. albicans strain SC5314 and its derived echinocandin-resistant mutants, which harbor an S645Y mutation in the CaFks1 β-1,3 glucan synthase drug target, suggesting potential therapeutic applicability for these combinations in the future.
doi:10.1371/journal.pone.0057672
PMCID: PMC3589401  PMID: 23472097
3.  Detection and Validation of Circulating Endothelial Cells, a Blood-based Diagnostic Marker of Acute Myocardial Infarction 
PLoS ONE  2013;8(3):e58478.
Background
Circulating endothelial cells (CECs) are markers of vascular damage that have clinical relevance in many diseases, including acute myocardial infarction (AMI), and may be predictors of treatment responses. Herein, we investigated the diagnostic and prognostic value of CEC monitoring in AMI patients and a murine model.
Methodology/Principal Findings
CECs were defined as Hoechst 33342+/CD45−/CD31+/CD146+/CD133− in human blood samples and Hoechst 33342+/CD45−/CD31+/KDR+/CD117− in murine samples. To evaluate the validity and variability of our CEC detection system, peripheral blood samples of vascular endothelial growth factor-treated athymic nude mice and AMI patients were collected and subjected to intra-assay analysis. CEC detection by flow cytometry and real-time PCR were compared. Blood samples were obtained from 61 AMI patients, 45 healthy volunteers and 19 samples of the original AMI patients accepted one month treatment, via flow cytometry and expressed as a percentage of peripheral blood mononuclear cells.
Results
Our CEC detection method was validated and had limited variability. CEC concentrations were higher in AMI patients compared to healthy controls. One month post-treatment, CECs levels decreased significantly.
Conclusions/Significance
CEC levels may be useful as a diagnostic and prognostic biomarker in AMI patients.
doi:10.1371/journal.pone.0058478
PMCID: PMC3587582  PMID: 23484031
4.  A bi-cistronic baculovirus expression vector for improved recombinant protein production 
Bioengineered Bugs  2012;3(2):127-130.
Baculoviruses are one of the most studied insect viruses both in basic virology research and in biotechnology applications. Incorporating an internal ribosome entry site (IRES) into the baculovirus genome generates bi-cistronic baculoviruses expression vectors that produce two genes of interest. The bi-cistronic baculoviruses also facilitate recombinant virus isolation and titer determination when the green fluorescent protein was co-expressed. Furthermore, when the secretion proteins were co-expressed with the cytosolic green fluorescent protein, the cell lysis and cytosolic protein released into the culture medium could be monitored by the green fluorescence, thus facilitating purification of the secreted proteins.
doi:10.4161/bbug.19388
PMCID: PMC3357334  PMID: 22539029
baculovirus; bi-cistronic; EGFP; IRES; secretion proteins
5.  Calcineurin Governs Thermotolerance and Virulence of Cryptococcus gattii 
G3: Genes|Genomes|Genetics  2013;3(3):527-539.
The pathogenic yeast Cryptococcus gattii, which is causing an outbreak in the Pacific Northwest region of North America, causes life-threatening pulmonary infections and meningoencephalitis in healthy individuals, unlike Cryptococcus neoformans, which commonly infects immunocompromised patients. In addition to a greater predilection for C. gattii to infect healthy hosts, the C. gattii genome sequence project revealed extensive chromosomal rearrangements compared with C. neoformans, showing genomic differences between the two Cryptococcus species. We investigated the roles of C. gattii calcineurin in three molecular types: VGIIa (R265), VGIIb (R272), and VGI (WM276). We found that calcineurin exhibits a differential requirement for growth on solid medium at 37°, as calcineurin mutants generated from R265 were more thermotolerant than mutants from R272 and WM276. We demonstrated that tolerance to calcineurin inhibitors (FK506, CsA) at 37° is linked with the VGIIa molecular type. The calcineurin mutants from the R272 background showed the most extensive growth and morphological defects (multivesicle and larger ring-like cells), as well as increased fluconazole susceptibility. Our cellular architecture examination showed that C. gattii and C. neoformans calcineurin mutants exhibit plasma membrane disruptions. Calcineurin in the C. gattii VGII molecular type plays a greater role in controlling cation homeostasis compared with that in C. gattii VGI and C. neoformans H99. Importantly, we demonstrate that C. gattii calcineurin is essential for virulence in a murine inhalation model, supporting C. gattii calcineurin as an attractive antifungal drug target.
doi:10.1534/g3.112.004242
PMCID: PMC3583459  PMID: 23450261
temperature sensitivity; pathogenicity; fluconazole tolerance; FK506; cyclosporin A; cation homeostasis; melanin; capsule
6.  Sex-Specific Correlations of Individual Heterozygosity, Parasite Load, and Scalation Asymmetry in a Sexually Dichromatic Lizard 
PLoS ONE  2013;8(2):e56720.
Heterozygosity-fitness correlations (HFCs) provide insights into the genetic bases of individual fitness variation in natural populations. However, despite decades of study, the biological significance of HFCs is still under debate. In this study, we investigated HFCs in a large population of the sexually dimorphic lizard Takydromus viridipunctatus (Lacertidae). Because of the high prevalence of parasitism from trombiculid mites in this lizard, we expect individual fitness (i.e., survival) to decrease with increasing parasite load. Furthermore, because morphological asymmetry is likely to influence individuals' mobility (i.e., limb asymmetry) and male biting ability during copulation (i.e., head asymmetry) in this species, we also hypothesize that individual fitness should decrease with increasing morphological asymmetry. Although we did not formally test the relationship between morphological asymmetry and fitness in this lizard, we demonstrated that survival decreased with increasing parasite load using a capture-mark-recapture data set. We used a separate sample of 140 lizards to test the correlations between individual heterozygosity (i.e., standardized mean d2 and HL based on 10 microsatellite loci) and the two fitness traits (i.e., parasite load and morphological asymmetry). We also evaluated and excluded the possibility that single-locus effects produced spurious HFCs. Our results suggest male-only, negative correlations between individual heterozygosity and parasite load and between individual heterozygosity and asymmetry, suggesting sex-specific, positive HFCs. Male T. viridipunctatus with higher heterozygosity tend to have lower parasite loads (i.e., higher survival) and lower asymmetry, providing a rare example of HFC in reptiles.
doi:10.1371/journal.pone.0056720
PMCID: PMC3581517  PMID: 23451073
7.  Dual-mode Modulation of Smad Signaling by Smad-interacting Protein Sip1 is Required for Myelination in the CNS 
Neuron  2012;73(4):713-728.
Myelination by oligodendrocytes in the central nervous system (CNS) is essential for proper brain function, yet the molecular determinants that control this process remain poorly understood. The basic helix-loop-helix transcription factors Olig1 and Olig2 promote myelination, whereas bone morphogenetic protein (BMP) and Wnt/β-catenin signaling inhibit myelination. Here we show that these opposing regulators of myelination are functionally linked by the Olig1/2 common target Smad-interacting protein-1 (Sip1). We demonstrate that Sip1 is an essential modulator of CNS myelination. Sip1 represses differentiation inhibitory signals by antagonizing BMP receptor activated-Smad activity while activating crucial oligodendrocyte-promoting factors. Importantly, a key Sip1-activated target, Smad7, is required for oligodendrocyte differentiation, and partially rescues differentiation defects caused by Sip1 loss. Smad7 promotes myelination by blocking the BMP and β-catenin negative regulatory pathways. Thus, our findings reveal that Sip1-mediated antagonism of inhibitory signaling is critical for promoting CNS myelination and point to new mediators for myelin repair.
doi:10.1016/j.neuron.2011.12.021
PMCID: PMC3293152  PMID: 22365546
8.  SCYL1BP1 modulates neurite outgrowth and regeneration by regulating the Mdm2/p53 pathway 
Molecular Biology of the Cell  2012;23(23):4506-4514.
SCYL1BP1 is a new regulator of the p53 pathway, which is required for neurite outgrowth and regeneration. SCYL1BP1 suppresses neurite outgrowth by directly inducing Mdm2 transcription and consequently p53 inhibition, suggesting that it might be a novel transcriptional regulator for regulating neurite outgrowth and regeneration.
SCY1-like 1–binding protein 1 (SCYL1BP1) is a newly identified transcriptional activator domain containing a protein with many unknown biological functions. Recently emerging evidence has revealed that it is a novel regulator of the p53 pathway, which is required for neurite outgrowth and regeneration. Here we present evidence that SCYL1BP1 inhibits nerve growth factor–mediated neurite outgrowth in PC12 cells and affects morphogenesis of primary cortical neurons by strongly decreasing the p53 protein level in vitro, all of which depends on SCYL1BP1's transcriptional activator domain. Exogenous p53 rescues neurite outgrowth and neuronal morphogenesis defects caused by SCYL1BP1. Furthermore, SCYL1BP1 can directly induce Mdm2 transcription, whereas inhibiting the function of Mdm2 by specific small interfering RNAs results in partial rescue of neurite outgrowth and neuronal morphogenesis defects induced by SCYL1BP1. In vivo experiments show that SCYL1BP1 can also depress axonal regeneration, whereas inhibiting the function of SCYL1BP1 by specific short hairpin RNA enhances it. Taken together, these data strongly suggested that SCYL1BP1 is a novel transcriptional activator in neurite outgrowth by directly modulating the Mdm2/p53-dependent pathway, which might play an important role in CNS development and axonal regeneration after injury.
doi:10.1091/mbc.E12-05-0362
PMCID: PMC3510013  PMID: 23051735
10.  Expression Status and Prognostic Significance of mTOR Pathway Members in Urothelial Carcinoma of Urinary Bladder Following Cystectomy 
Cancer  2010;116(23):5517-5526.
Background
Bladder urothelial carcinoma (UrCa) proclaims high rates of mortality and morbidity. Identifying novel molecular prognostic factors and targets of therapy is crucial. mTOR pathway plays a pivotal role in establishing cell shape, migration and proliferation.
Design
TMA were constructed from 132 cystectomies (1994-2002). IHC was performed for Pten, c-Myc, p27, phosAkt, phosS6, and 4E-BP1. Markers were evaluated for pattern, percent and intensity of staining.
Results
Mean length of F/U was 62.6 months (1-182). Disease progression, overall survival (OS) and disease specific survival (DSS) rates were 42%, 60% and 68%, respectively.
Pten showed loss of expression in 35% of UrCa. All markers showed lower expression in invasive UrCa compared to benign urothelium with the exception of 4E-BP1. Pten, p27, phosAkt, phosS6 and 4E-BP1 expression correlated with pathologic stage (pT; p<0.03). Pten, 4E-BP1, and phosAkt expression correlated with divergent aggressive histology and invasion.
PhosS6 expression inversely predicted OS (p=0.01), DSS (p=0.001) and progression (p=0.05). c-Myc expression inversely predicted progression (p=0.01).
In a multivariate analysis model that included: TNM stage grouping, divergent aggressive histology, concomitant CIS, phosS6 and c-Myc expression; phosS6 was an independent predictor of DSS (p=0.03; HR: -.19) while c-Myc was an independent predictor of progression (p=0.02; HR:-.38). In a second model substituting organ confined disease and lymph node status for TNM stage grouping, phosS6 and c-Myc remained independent predictors of DSS (p=0.03; HR: -.21) and progression (p=0.03; HR:-.34), respectively.
Conclusions
We found an overall downregulation of mTOR pathway in UrCa. PhosS6 independently predicted DSS and c-Myc independently predicted progression.
doi:10.1002/cncr.25502
PMCID: PMC3568488  PMID: 20939013
mTOR; Pten; Akt; phos S6; 4E-BP1; c-Myc; p27; urothelial carcinoma; bladder
11.  Generalist passerine pollination of a winter-flowering fruit tree in central China 
Annals of Botany  2011;109(2):379-384.
Background and Aims
Winter-flowering plants outside the tropics may experience a shortage of pollinator service, given that insect activity is largely limited by low temperature. Birds can be alternative pollinators for these plants, but experimental evidence for the pollination role of birds in winter-flowering plants is scarce.
Methods
Pollinator visitation to the loquat, Eriobotrya japonica (Rosaceae), was observed across the flowering season from November to January for two years in central China. Self- and cross-hand pollination was conducted in the field to investigate self-compatibility and pollen limitation. In addition, inflorescences were covered by bird cages and nylon mesh nets to exclude birds and all animal pollinators, respectively, to investigate the pollination role of birds in seed production.
Results
Self-fertilization in the loquat yielded few seeds. In early winter insect visit frequency was relatively higher, while in late winter insect pollinators were absent and two passerine birds (Pycnonotus sinensis and Zosterops japonicus) became the major floral visitors. However, seed-set of open-pollinated flowers did not differ between early and late winter. Exclusion of bird visitation greatly reduced seed-set, indicating that passerine birds were important pollinators for the loquat in late winter. The whitish perigynous flowers reward passerines with relatively large volumes of dilute nectar. Our observation on the loquat and other Rosaceae species suggested that perigyny might be related to bird pollination but the association needs further study.
Conclusions
These findings suggest that floral traits and phenology would be favoured to attract bird pollinators in cold weather, in which insect activity is limited.
doi:10.1093/aob/mcr293
PMCID: PMC3268538  PMID: 22112440
Winter flowering; bird pollination; Pycnonotus sinensis; generalist pollination system; perigyny; self-incompatibility; ornithophily
13.  Combining the negative lymph nodes count with the ratio of positive and removed lymph nodes can better predict the postoperative survival in cervical cancer patients 
Background
To evaluate the impacts of the negative lymph nodes (NLNs) count on the prognostic prediction of the ratio of positive and removed lymph nodes (RPL) in cervical cancer patients after radical hysterectomy and pelvic lymphadenectomy (RHPL).
Methods
The positive and negative lymph node counts were calculated for 609 postoperative cervical cancer patients. The 5-year survival rate (5-YSR) was examined according to clinicopathologic variables. Cox regression was used to identify independent prognostic factors.
Results
The NLNs count cutoffs were determined to be 10 and 25 with 5-YSR of 62.8% and 80.5%. The RPL of 13 patients who had the NLNs count of 10 or fewer was >20%. Among 242 patients who had 10 < NLNs count ≤ 25, 194 without positive nodes had the 5-YSR of 77.8%, 31 with 0% < RPL ≤ 5% had the 5-YSR of 3.2%, 15 with RPL > 20% had died when follow-up was completed. Among 354 patients who had NLNs count >25, 185 without positive nodes had the 5-YSR of 87.6%, 6 with 0% < RPL ≤ 5% had the 5-YSR of 25%, 15 with 5% < RPL ≤ 20% had the 5-YSR of 4.5%, and 2 with RPL >20% had died when follow-up was completed. Furthermore, stage, histologic grade and RPL were independently correlated with overall survival of cervical cancer patients after RHPL in the multivariate analysis.
Conclusions
RPL was an independent prognostic factor. The NLNs count is a key factor for improvement of survival prediction of RPL in cervical cancer.
doi:10.1186/1475-2867-13-6
PMCID: PMC3576300  PMID: 23374254
Cervical cancer; Lymph node; Pelvic lymphadenectomy; Prognosis
14.  Correlations between cytoplasmic CSE1L in neoplastic colorectal glands and depth of tumor penetration and cancer stage 
Background
Colorectal carcinomas spread easily to nearby tissues around the colon or rectum, and display strong potential for invasion and metastasis. CSE1L, the chromosome segregation 1-like protein, is implicated in cancer progression and is located in both the cytoplasm and nuclei of tumor cells. We investigated the prognostic significance of cytoplasmic vs. nuclear CSE1L expression in colorectal cancer.
Methods
The invasion- and metastasis-stimulating activities of CSE1L were studied by in vitro invasion and animal experiments. CSE1L expression in colorectal cancer was assayed by immunohistochemistry, with tissue microarray consisting of 128 surgically resected specimens; and scored using a semiquantitative method. The correlations between CSE1L expression and clinicopathological parameters were analyzed.
Results
CSE1L overexpression was associated with increased invasiveness and metastasis of cancer cells. Non-neoplastic colorectal glands showed minimal CSE1L staining, whereas most colorectal carcinomas (99.2%, 127/128) were significantly positive for CSE1L staining. Cytoplasmic CSE1L was associated with cancer stage (P=0.003) and depth of tumor penetration (P=0.007). Cytoplasmic CSE1L expression also correlated with lymph node metastasis of the disease in Cox regression analysis
Conclusions
CSE1L regulates the invasiveness and metastasis of cancer cells, and immunohistochemical analysis of cytoplasmic CSE1L in colorectal tumors may provide a useful aid to prognosis.
doi:10.1186/1479-5876-11-29
PMCID: PMC3564816  PMID: 23369209
Colorectal cancer; CSE1L; Cytoplasm; Invasion; Metastasis; Nucleus
16.  The Impact of Media Reporting on the Emergence of Charcoal Burning Suicide in Taiwan 
PLoS ONE  2013;8(1):e55000.
We investigated the association of the intensity of newspaper reporting of charcoal burning suicide with the incidence of such deaths in Taiwan during 1998–2002. A counting process approach was used to estimate the incidence of suicides and intensity of news reporting. Conditional Poisson generalized linear autoregressive models were performed to assess the association of the intensity of newspaper reporting of charcoal burning and non-charcoal burning suicides with the actual number of charcoal burning and non-charcoal burning suicides the following day. We found that increases in the reporting of charcoal burning suicide were associated with increases in the incidence of charcoal burning suicide on the following day, with each reported charcoal burning news item being associated with a 16% increase in next day charcoal burning suicide (p<.0001). However, the reporting of other methods of suicide was not related to their incidence. We conclude that extensive media reporting of charcoal burning suicides appears to have contributed to the rapid rise in the incidence of the novel method in Taiwan during the initial stage of the suicide epidemic. Regulating media reporting of novel suicide methods may prevent an epidemic spread of such new methods.
doi:10.1371/journal.pone.0055000
PMCID: PMC3559477  PMID: 23383027
17.  Cross Sectional Survey of Influenza Antibodies before and during the 2009 Pandemic in Shenzhen, China 
PLoS ONE  2013;8(1):e53847.
Much information is available for the 2009 H1N1 influenza immunity response, but little is known about the antibody change in seasonal influenza before and during the novel influenza A pandemic. In this study, we conducted a cross-sectional serological survey of 4 types of major seasonal influenza in March and September 2009 on a full range of age groups, to investigate seasonal influenza immunity response before and during the outbreak of the sH1N1 influenza in Shenzhen – the largest migration city in China. We found that the 0–5 age group had an increased antibody level for all types of seasonal influenza during the pandemic compared to the pre-outbreak level, in contrast with almost all other age groups, in which the antibody level decreased. Also, distinct from the antibodies of A/H3N2, B/Yamagata and B/Victoria that decreased significantly during the 2009 H1N1 pandemic, the antibody of A/H1N1 showed no statistical difference from the pre-outbreak level. The results suggest that the antibodies against the 2009 sH1N1 cross-reacted with seasonal H1N1. Moreover, the 0–5 age group was under attack by both seasonal and 2009 H1N1 influenza during the pandemic, hence vaccination merely against a new strain of flu might not be enough to protect the youngest group.
doi:10.1371/journal.pone.0053847
PMCID: PMC3558489  PMID: 23382854
18.  CNT Reinforced Hybrid Microgels as Scaffold Materials for Cell Encapsulation 
ACS Nano  2011;6(1):362-372.
Hydrogels that mimic biological extracellular matrix (ECM) can provide cells with mechanical support and signaling cues to regulate their behavior. However, despite the ability of hydrogels to generate artificial ECM that can modulate cellular behavior, they often lack the mechanical strength needed for many tissue constructs. Here, we present reinforced CNT-gelatin methacrylate (GelMA) hybrid as a biocompatible, cell-responsive hydrogel platform for creating cell-laden three dimensional (3D) constructs. The addition of CNTs successfully reinforced GelMA hydrogels without decreasing their porosity or inhibiting cell growth. The CNT-GelMA hybrids were also photopatternable allowing for easy fabrication of microscale structures without harsh processes. NIH-3T3 cells and human mesenchymal stem cells (hMSCs) readily spread and proliferated after encapsulation in CNT-GelMA hybrid microgels. By controlling the amount of CNTs incorporated into the GelMA hydrogel system, we demonstrated that the mechanical properties of the hybrid material can be tuned making it suitable for various tissue engineering applications. Furthermore, due to the high pattern fidelity and resolution of CNT incorporated GelMA, it can be used for in vitro cell studies or fabricating complex 3D biomimetic tissue-like structures.
doi:10.1021/nn203711s
PMCID: PMC3401631  PMID: 22117858
Carbon nanotubes; Cell-laden microgels; Tunable Stiffness; Biocompatibility; 3D tissue engineering
19.  CD33+/p-STAT1+ double-positive cell as a prognostic factor for stage IIIa gastric cancer 
Tumor-infiltrating immune cells are associated with tumor prognosis, although the type of immune cells responsible for local immune escape is still unknown. This study examined the relationship between gastric cancer survival and the density of immune cells, including CD8+ T cells, CD20+ B cells, and CD33+/p-STAT1+ cells, which represent myeloid-derived suppressor cells, to evaluate the role of immune cells in the progression of gastric cancer. One hundred pathologically confirmed specimens were obtained from stage IIIa gastric cancers between 2003 and 2006 at Sun Yat-sen University Cancer Center, China. The density of tumor-infiltrating immune cells in tumor tissue was examined using immunohistochemical analysis. Clinicopathologic parameters and the survival rate were analyzed in relation to the density of immune cells. A high density of CD8+ T cells and CD20+ B cells was associated with a good clinical outcome, but a high density of CD33+/p-STAT1+ cells was associated with a poor clinical outcome. Most importantly, the density of CD33+/p-STAT1+ cells was an independent prognostic factor and inversely related to the infiltration of CD8+ T cells. Although the infiltration of CD8+ T cells and CD20+ B cells is involved in the progression of gastric cancer, these data suggest that CD33+/p-STAT1+ cells play a central role in the regulation of the local immune response, suggesting that CD33+/p-STAT1+ cells might be therapeutic targets in gastric cancer.
doi:10.1007/s12032-012-0442-2
PMCID: PMC3586391  PMID: 23307253
Gastric cancer; CD33; STAT1; T cell; B cell; Regulation
20.  Cellobiose-Specific Phosphotransferase System of Klebsiella pneumoniae and Its Importance in Biofilm Formation and Virulence 
Infection and Immunity  2012;80(7):2464-2472.
Klebsiella pneumoniae is a Gram-negative bacillus belonging to the family Enterobacteriaceae. In the past 20 years, K. pneumoniae has become the predominant pathogen causing community-acquired pyogenic liver abscess (PLA). The formation of biofilm facilitates bacterial colonization and has been implicated in reduced susceptibility to the host immune response. To investigate genes related to biofilm formation in a PLA-associated K. pneumoniae strain, a transposon mutant library was screened by microtiter plate assay to identify isolates impaired for biofilm formation. One of the mutants was disrupted in celB, encoding the putative cellobiose-specific subunit IIC of enzyme II (EIIC) of a carbohydrate phosphotransferase system (PTS). This transmembrane protein is responsible for recognizing and binding specific sugars and transporting them across the cell membrane into the cytoplasm. Deletion and chromosomal complementation of celB confirmed, by microtiter plate and slide culture assays, that celB was indeed responsible for biofilm formation. Cellobiose-specific PTS activities of deletion mutants grown in LB broth and 0.005% cellobiose minimal medium were markedly lower than that of the wild-type strain grown under the same conditions, thereby confirming the involvement of celB in cellobiose transport. In 0.005% cellobiose minimal medium, the celB mutant showed a delay in growth compared to the wild-type strain. In a mouse model of intragastric infection, deletion of the celB gene increased the survival rate from 12.5% to 87.5%, which suggests that the celB deletion mutant also exhibited reduced virulence. Thus, the celB locus of K. pneumoniae may contribute to biofilm formation and virulence through the metabolism of cellobiose.
doi:10.1128/IAI.06247-11
PMCID: PMC3416469  PMID: 22566508
21.  Recipient Cytotoxic T Lymphocyte Antigen 4 +49 Single-Nucleotide Polymorphism Is Not Associated with Acute Rejection after Liver Transplantation in Chinese Population 
Objective: Single-nucleotide polymorphisms (SNPs) in Cytotoxic T lymphocyte antigen 4 (CTLA-4) gene have been detected and proved to associate with the incidence of rejection after transplantation. However, previous studies gained inconsistent results about the association between CTLA-4 +49 single-nucleotide polymorphism and susceptibility of allograft rejection. Therefore we sought to clarify whether CTLA-4 +49 SNP influences the incidence of acute rejection after liver transplantation in Chinese population. Methods: Genomic DNA from 335 liver transplant recipients was genotyped for CTLA-4 +49 SNP by DNA sequencing. Acute rejection was confirmed by pathologic evidences. The association between CTLA-4 +49 SNP and incidence of acute rejection was then analyzed by dominant, recessive, codominant and overdominant models. Results: The incidence of acute rejection within the first 3 months was 11.9%. In acute rejectors, the frequency was 45% for G/G, 10% for A/A and 45% for A/G respectively, compared with 47.5% for G/G, 10.8% for A/A and 41.7% for A/G in non-acute rejectors. And no significant difference of allele distribution between these 2 groups was detected. Conclusions: This study suggests that CTLA-4 +49 SNP is not associated with acute rejection after liver transplantation in Chinese population.
doi:10.7150/ijms.5511
PMCID: PMC3558713  PMID: 23372431
Cytotoxic T lymphocyte antigen 4; liver transplantation; Single Nucleotide Polymorphism.
22.  Gardenia jasminoides attenuates hepatocellular injury and fibrosis in bile duct-ligated rats and human hepatic stellate cells 
AIM: To investigate the anti-hepatofibrotic effects of Gardenia jasminoides in liver fibrosis.
METHODS: Male Sprague-Dawley rats underwent common bile duct ligation (BDL) for 14 d and were treated with Gardenia jasminoides by gavage. The effects of Gardenia jasminoides on liver fibrosis and the detailed molecular mechanisms were also assessed in human hepatic stellate cells (LX-2) in vitro.
RESULTS: Treatment with Gardenia jasminoides decreased serum alanine aminotransferase (BDL vs BDL + 100 mg/kg Gardenia jasminoides, 146.6 ± 15 U/L vs 77 ± 6.5 U/L, P = 0.0007) and aspartate aminotransferase (BDL vs BDL + 100 mg/kg Gardenia jasminoides, 188 ± 35.2 U/L vs 128 ± 19 U/L, P = 0.005) as well as hydroxyproline (BDL vs BDL + 100 mg/kg Gardenia jasminoides, 438 ± 40.2 μg/g vs 228 ± 10.3 μg/g liver tissue, P = 0.004) after BDL. Furthermore, Gardenia jasminoides significantly reduced liver mRNA and/or protein expression of transforming growth factor β1 (TGF-β1), collagen type I (Col I) and α-smooth muscle actin (α-SMA). Gardenia jasminoides significantly suppressed the upregulation of TGF-β1, Col I and α-SMA in LX-2 exposed to recombinant TGF-β1. Moreover, Gardenia jasminoides inhibited TGF-β1-induced Smad2 phosphorylation in LX-2 cells.
CONCLUSION: Gardenia jasminoides exerts antifibrotic effects in the liver fibrosis and may represent a novel antifibrotic agent.
doi:10.3748/wjg.v18.i48.7158
PMCID: PMC3544017  PMID: 23326120
Gardenia jasminoides; Liver fibrosis; Collagen type I; Transforming growth factor-β1/Smad2 pathway; α-smooth muscle actin
23.  Comparison between air and carbon dioxide insufflation in the endoscopic submucosal excavation of gastrointestinal stromal tumors 
AIM: To evaluate the safety and efficacy of CO2 insufflation compared with air insufflation in the endoscopic submucosal excavation (ESE) of gastrointestinal stromal tumors.
METHODS: Sixty patients were randomized to undergo endoscopic submucosal excavation, with the CO2 group (n = 30) and the air group (n = 30) undergoing CO2 insufflation and air insufflation in the ESE, respectively. The end-tidal CO2 level (pETCO2) was observed at 4 time points: at the beginning of ESE, at total removal of the tumors, at completed wound management, and 10 min after ESE. Additionally, the patients’ experience of pain at 1, 3, 6 and 24 h after the examination was registered using a visual analog scale (VAS).
RESULTS: Both the CO2 group and air group were similar in mean age, sex, body mass index (all P > 0.05). There were no significant differences in PetCO2 values before and after the procedure (P > 0.05). However, the pain scores after the ESE at different time points in the CO2 group decreased significantly compared with the air group (1 h: 21.2 ± 3.4 vs 61.5 ± 1.7; 3 h: 8.5 ± 0.7 vs 42.9 ± 1.3; 6 h: 4.4 ± 1.6 vs 27.6 ± 1.2; 24 h: 2.3 ± 0.4 vs 21.4 ± 0.7, P < 0.05). Meanwhile, the percentage of VAS scores of 0 in the CO2 group after 1, 3, 6 and 24 h was significantly higher than that in the air group (60.7 ± 1.4 vs 18.9 ± 1.5, 81.5 ± 2.3 vs 20.6 ± 1.2, 89.2 ± 0.7 vs 36.8 ± 0.9, 91.3 ± 0.8 vs 63.8 ± 1.3, respectively, P < 0.05). Moreover, the condition of the CO2 group was better than that of the air group with respect to anal exsufflation.
CONCLUSION: Insufflation of CO2 in the ESE of gastrointestinal stromal tumors will not cause CO2 retention and it may significantly reduce the level of pain, thus it is safe and effective.
doi:10.3748/wjg.v18.i48.7296
PMCID: PMC3544033  PMID: 23326136
Carbon dioxide insufflation; Endoscopic submucosal excavation; Gastrointestinal tract; Stromal tumor; Treatment
24.  Self-reported psychopathology and health-related quality of life in heroin users treated with methadone 
Background
Health-related quality of life (HRQoL) remains poor among heroin users, even after being treated with methadone. Evidence regarding self-reported psychopathology and HRQoL in heroin users is also limited. The present study aimed to investigate the association between self-reported psychopathology and HRQoL in Asian heroin users treated with methadone.
Methods
Thirty-nine heroin users treated with methadone and 39 healthy controls were recruited. Both groups self-reported on demographic data, the Brief Symptom Rating Scale, EuroQoL-5D, and World Health Organization Questionnaire on Quality of Life: Short Form. We compared clinical characteristics, psychopathology, and HRQoL between the two study groups. Correlation and regression analyses were conducted to explore the association between psychopathology and HRQoL in the heroin user group.
Results
Heroin users had more psychopathology and worse HRQoL than healthy controls. The HRQoL of heroin users had significant correlations with Brief Symptom Rating Scale scores. HRQoL could be predicted by depression, anxiety, paranoia, and additional symptoms (ie, poor appetite and sleep difficulties) independently.
Conclusion
Self-reported psychopathology, depression, anxiety, paranoia, poor appetite, and sleep difficulties had a negative impact on each domain of HRQoL among heroin users treated with methadone. The importance of the environmental domain of HRQoL is discussed. Clinicians should recognize comorbid psychiatric symptoms early on to improve HRQoL in heroin users.
doi:10.2147/NDT.S37284
PMCID: PMC3534320  PMID: 23293525
heroin abuse; Brief Symptom Rating Scale; World Health Organization questionnaire on quality of life
25.  Analysis of Genetic Linkage of HIV From Couples Enrolled in the HIV Prevention Trials Network 052 Trial 
The Journal of Infectious Diseases  2011;204(12):1918-1926.
Background. The HIV Prevention Trials Network (HPTN) 052 trial demonstrated that early initiation of antiretroviral therapy (ART) reduces human immunodeficiency virus (HIV) transmission from HIV-infected adults (index participants) to their HIV-uninfected sexual partners. We analyzed HIV from 38 index-partner pairs and 80 unrelated index participants (controls) to assess the linkage of seroconversion events.
Methods. Linkage was assessed using phylogenetic analysis of HIV pol sequences and Bayesian analysis of genetic distances between pol sequences from index-partner pairs and controls. Selected samples were also analyzed using next-generation sequencing (env region).
Results. In 29 of the 38 (76.3%) cases analyzed, the index was the likely source of the partner’s HIV infection (linked). In 7 cases (18.4%), the partner was most likely infected from a source other than the index participant (unlinked). In 2 cases (5.3%), linkage status could not be definitively established.
Conclusions. Nearly one-fifth of the seroconversion events in HPTN 052 were unlinked. The association of early ART and reduced HIV transmission was stronger when the analysis included only linked events. This underscores the importance of assessing the genetic linkage of HIV seroconversion events in HIV prevention studies involving serodiscordant couples.
doi:10.1093/infdis/jir651
PMCID: PMC3209811  PMID: 21990420

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