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2.  Multisensory Interface for 5D Stem Cell Image Volumes 
Biological imaging of live cell and tissue using 3D microscopy is able to capture time-lapse image sequences showing multiple molecular markers labeling different biological structures simultaneously. In order to analyze this complex multi-dimensional image sequence data, there is a need for automated quantitative algorithms, and for methods to visualize and interact with both the data and the analytical results. Traditional computational human input devices such as the keyboard and mouse are no longer adequate for complex tasks such as manipulating and navigating 3+ dimensional volumes. In this paper, we have developed a new interaction system for interfacing with big data sets using the human visual system together with touch, force and audio feedback. This system includes real-time dynamic 3D visualization, haptic interaction via exoskeletal glove, and tonal auditory components that seamlessly create an immersive environment for efficient qualitative analysis.
PMCID: PMC4321857  PMID: 25570174
3.  Does the Arcto-Tertiary Biogeographic Hypothesis Explain the Disjunct Distribution of Northern Hemisphere Herbaceous Plants? The Case of Meehania (Lamiaceae) 
PLoS ONE  2015;10(2):e0117171.
Despite considerable progress, many details regarding the evolution of the Arcto-Tertiary flora, including the timing, direction, and relative importance of migration routes in the evolution of woody and herbaceous taxa of the Northern Hemisphere, remain poorly understood. Meehania (Lamiaceae) comprises seven species and five subspecies of annual or perennial herbs, and is one of the few Lamiaceae genera known to have an exclusively disjunct distribution between eastern Asia and eastern North America. We analyzed the phylogeny and biogeographical history of Meehania to explore how the Arcto-Tertiary biogeographic hypothesis and two possible migration routes explain the disjunct distribution of Northern Hemisphere herbaceous plants. Parsimony and Bayesian inference were used for phylogenetic analyses based on five plastid sequences (rbcL, rps16, rpl32-trnH, psbA-trnH, and trnL-F) and two nuclear (ITS and ETS) gene regions. Divergence times and biogeographic inferences were performed using Bayesian methods as implemented in BEAST and S-DIVA, respectively. Analyses including 11 of the 12 known Meehania taxa revealed incongruence between the chloroplast and nuclear trees, particularly in the positions of Glechoma and Meehania cordata, possibly indicating allopolyploidy with chloroplast capture in the late Miocene. Based on nrDNA, Meehania is monophyletic, and the North American species M. cordata is sister to a clade containing the eastern Asian species. The divergence time between the North American M. cordata and the eastern Asian species occurred about 9.81 Mya according to the Bayesian relaxed clock methods applied to the combined nuclear data. Biogeographic analyses suggest a primary role of the Arcto-Tertiary flora in the study taxa distribution, with a northeast Asian origin of Meehania. Our results suggest an Arcto-Tertiary origin of Meehania, with its present distribution most probably being a result of vicariance and southward migrations of populations during climatic oscillations in the middle Miocene with subsequent migration into eastern North America via the Bering land bridge in the late Miocene.
PMCID: PMC4319762  PMID: 25658699
4.  Digital gene expression analysis of gene expression differences within Brassica diploids and allopolyploids 
BMC Plant Biology  2015;15:22.
Brassica includes many successfully cultivated crop species of polyploid origin, either by ancestral genome triplication or by hybridization between two diploid progenitors, displaying complex repetitive sequences and transposons. The U’s triangle, which consists of three diploids and three amphidiploids, is optimal for the analysis of complicated genomes after polyploidization. Next-generation sequencing enables the transcriptome profiling of polyploids on a global scale.
We examined the gene expression patterns of three diploids (Brassica rapa, B. nigra, and B. oleracea) and three amphidiploids (B. napus, B. juncea, and B. carinata) via digital gene expression analysis. In total, the libraries generated between 5.7 and 6.1 million raw reads, and the clean tags of each library were mapped to 18547–21995 genes of B. rapa genome. The unambiguous tag-mapped genes in the libraries were compared. Moreover, the majority of differentially expressed genes (DEGs) were explored among diploids as well as between diploids and amphidiploids. Gene ontological analysis was performed to functionally categorize these DEGs into different classes. The Kyoto Encyclopedia of Genes and Genomes analysis was performed to assign these DEGs into approximately 120 pathways, among which the metabolic pathway, biosynthesis of secondary metabolites, and peroxisomal pathway were enriched. The non-additive genes in Brassica amphidiploids were analyzed, and the results indicated that orthologous genes in polyploids are frequently expressed in a non-additive pattern. Methyltransferase genes showed differential expression pattern in Brassica species.
Our results provided an understanding of the transcriptome complexity of natural Brassica species. The gene expression changes in diploids and allopolyploids may help elucidate the morphological and physiological differences among Brassica species.
Electronic supplementary material
The online version of this article (doi:10.1186/s12870-015-0417-5) contains supplementary material, which is available to authorized users.
PMCID: PMC4312607  PMID: 25623840
Brassica spp; Polyploidization; Sequencing; Digital gene expression (DGE)
5.  Cell Cycle-Independent Phospho-Regulation of Fkh2 during Hyphal Growth Regulates Candida albicans Pathogenesis 
PLoS Pathogens  2015;11(1):e1004630.
The opportunistic human fungal pathogen, Candida albicans, undergoes morphological and transcriptional adaptation in the switch from commensalism to pathogenicity. Although previous gene-knockout studies have identified many factors involved in this transformation, it remains unclear how these factors are regulated to coordinate the switch. Investigating morphogenetic control by post-translational phosphorylation has generated important regulatory insights into this process, especially focusing on coordinated control by the cyclin-dependent kinase Cdc28. Here we have identified the Fkh2 transcription factor as a regulatory target of both Cdc28 and the cell wall biosynthesis kinase Cbk1, in a role distinct from its conserved function in cell cycle progression. In stationary phase yeast cells 2D gel electrophoresis shows that there is a diverse pool of Fkh2 phospho-isoforms. For a short window on hyphal induction, far before START in the cell cycle, the phosphorylation profile is transformed before reverting to the yeast profile. This transformation does not occur when stationary phase cells are reinoculated into fresh medium supporting yeast growth. Mass spectrometry and mutational analyses identified residues phosphorylated by Cdc28 and Cbk1. Substitution of these residues with non-phosphorylatable alanine altered the yeast phosphorylation profile and abrogated the characteristic transformation to the hyphal profile. Transcript profiling of the phosphorylation site mutant revealed that the hyphal phosphorylation profile is required for the expression of genes involved in pathogenesis, host interaction and biofilm formation. We confirmed that these changes in gene expression resulted in corresponding defects in pathogenic processes. Furthermore, we identified that Fkh2 interacts with the chromatin modifier Pob3 in a phosphorylation-dependent manner, thereby providing a possible mechanism by which the phosphorylation of Fkh2 regulates its specificity. Thus, we have discovered a novel cell cycle-independent phospho-regulatory event that subverts a key component of the cell cycle machinery to a role in the switch from commensalism to pathogenicity.
Author Summary
The fungus Candida albicans is a commensal in the human microbiota, responsible for superficial infections such as oral and vaginal thrush. However, it can become highly virulent, causing life-threatening systemic candidemia in severely immunocompromised patients, including those taking immunosuppressive drugs for transplantation, sufferers of AIDS and neutropenia, and individuals undergoing chemotherapy or at extremes of age. With a rapidly increasing ageing population worldwide, C. albicans and other fungal pathogens will become more prevalent, demanding a greater understanding of their pathogenesis for the development of effective therapeutics. Fungal pathogenicity requires a coordinated change in the pattern of gene expression orchestrated by a set of transcription factors. Here we have discovered that a transcription factor, Fkh2, is modified by phosphorylation under the control of the kinases Cdc28 and Cbk1 in response to conditions that activate virulence factor expression. Fkh2 is involved in a wide variety of cellular processes including cell proliferation, but this phosphorylation endows it with a specialized function in promoting the expression of genes required for tissue invasion, biofilm formation, and pathogenesis in the host. This study highlights the role of protein phosphorylation in regulating pathogenesis and furthers our understanding of the pathogenic switch in this important opportunistic fungal pathogen.
PMCID: PMC4305328  PMID: 25617770
6.  A Long Noncoding RNA Perturbs the Circadian Rhythm of Hepatoma Cells to Facilitate Hepatocarcinogenesis12 
Neoplasia (New York, N.Y.)  2015;17(1):79-88.
Clock circadian regulator (CLOCK)/brain and muscle arnt-like protein-1 (BMAL1) complex governs the regulation of circadian rhythm through triggering periodic alterations of gene expression. However, the underlying mechanism of circadian clock disruption in hepatocellular carcinoma (HCC) remains unclear. Here, we report that a long noncoding RNA (lncRNA), highly upregulated in liver cancer (HULC), contributes to the perturbations in circadian rhythm of hepatoma cells. Our observations showed that HULC was able to heighten the expression levels of CLOCK and its downstream circadian oscillators, such as period circadian clock 1 and cryptochrome circadian clock 1, in hepatoma cells. Strikingly, HULC altered the expression pattern and prolonged the periodic expression of CLOCK in hepatoma cells. Mechanistically, the complementary base pairing between HULC and the 5' untranslated region of CLOCK mRNA underlay the HULC-modulated expression of CLOCK, and the mutants in the complementary region failed to achieve the event. Moreover, immunohistochemistry staining and quantitative real-time polymerase chain reaction validated that the levels of CLOCK were elevated in HCC tissues, and the expression levels of HULC were positively associated with those of CLOCK in clinical HCC samples. In functional experiments, our data exhibited that CLOCK was implicated in the HULC-accelerated proliferation of hepatoma cells in vitro and in vivo. Taken together, our data show that an lncRNA, HULC, is responsible for the perturbations in circadian rhythm through upregulating circadian oscillator CLOCK in hepatoma cells, resulting in the promotion of hepatocarcinogenesis. Thus, our finding provides new insights into the mechanism by which lncRNA accelerates hepatocarcinogenesis through disturbing circadian rhythm of HCC.
PMCID: PMC4309731  PMID: 25622901
8.  Intestinal Parasite Co-infection among Pulmonary Tuberculosis Cases without Human Immunodeficiency Virus Infection in a Rural County in China 
Epidemiologic studies of co-infection with tuberculosis (TB) and intestinal parasites in humans have not been extensively investigated in China. A cross-section study was conducted in a rural county of Henan Province, China. Pulmonary TB (PTB) case-patients receiving treatment for infection with Mycobacterium tuberculosis and healthy controls matched for geographic area, age, and sex were surveyed by using questionnaires. Fecal and blood specimens were collected for detection of intestinal parasites, routine blood examination, and infection with human immunodeficiency virus. The chi-square test was used for univariate analysis and multivariate logistic regression models were used to adjust for potential confounding factors. A total of 369 persons with PTB and 366 healthy controls were included; all participants were negative for human immunodeficiency virus. The overall prevalence of intestinal parasites in persons with PTB was 14.9%, including intestinal protozoa (7.9%) and helminthes (7.6%). The infection spectrum of intestinal parasites was Entamoeba spp. (1.4%), Blastocystis hominis (6.2%), Trichomonas hominis (0.3%), Clonorchis sinensis (0.3%), Ascaris lumbricoides (0.5%), Trichuris trichiura (2.2%), and hookworm (4.6%). The prevalence of intestinal parasites showed no significant difference between persons with PTB and healthy controls after adjusting for potential confounding factors. There was no factor that affected infection rates for intestinal parasites between the two groups. Infection with intestinal parasites of persons with PTB was associated with female sex (adjusted odds ratio [AOR] = 2.05, 95% confidence interval [CI] = 1.01–4.17), body mass index ≤ 19 (AOR = 3.02, 95% CI = 1.47–6.20), and anemia (AOR = 2.43, 95% CI = 1.17–5.03). Infection of healthy controls was only associated with an annual labor time in farmlands > 2 months (AOR = 4.50, 95% CI = 2.03–10.00). In addition, there was no significant trend between rates of infection with intestinal parasites and duration of receiving treatment for infection with M. tuberculosis in persons with PTB. The prevalence of intestinal parasites was not higher in persons with PTB, and there was no evidence that PTB increased susceptibility to intestinal parasites in this study. However, for patients with PTB, women and patients with comorbidities were more likely to be infected with intestinal parasites.
PMCID: PMC3886404  PMID: 24166044
9.  Proteomic Profiling of Nitrosative Stress: Protein S-Oxidation Accompanies S-Nitrosylation 
ACS Chemical Biology  2014;9(3):821-830.
Reversible chemical modifications of protein cysteine residues by S-nitrosylation and S-oxidation are increasingly recognized as important regulatory mechanisms for many protein classes associated with cellular signaling and stress response. Both modifications may theoretically occur under cellular nitrosative or nitroxidative stress. Therefore, a proteomic isotope-coded approach to parallel, quantitative analysis of cysteome S-nitrosylation and S-oxidation was developed. Modifications of cysteine residues of (i) human glutathione-S-transferase P1-1 (GSTP1) and (ii) the schistosomiasis drug target thioredoxin glutathione reductase (TGR) were studied. Both S-nitrosylation (SNO) and S-oxidation to disulfide (SS) were observed for reactive cysteines, dependent on concentration of added S-nitrosocysteine (CysNO) and independent of oxygen. SNO and SS modifications of GSTP1 were quantified and compared for therapeutically relevant NO and HNO donors from different chemical classes, revealing oxidative modification for all donors. Observations on GSTP1 were extended to cell cultures, analyzed after lysis and in-gel digestion. Treatment of living neuronal cells with CysNO, to induce nitrosative stress, caused levels of S-nitrosylation and S-oxidation of GSTP1 comparable to those of cell-free studies. Cysteine modifications of PARK7/DJ-1, peroxiredoxin-2, and other proteins were identified, quantified, and compared to overall levels of protein S-nitrosylation. The new methodology has allowed identification and quantitation of specific cysteome modifications, demonstrating that nitroxidation to protein disulfides occurs concurrently with S-nitrosylation to protein-SNO in recombinant proteins and living cells under nitrosative stress.
PMCID: PMC3985710  PMID: 24397869
10.  The evolution of nanopore sequencing 
Frontiers in Genetics  2015;5:449.
The “$1000 Genome” project has been drawing increasing attention since its launch a decade ago. Nanopore sequencing, the third-generation, is believed to be one of the most promising sequencing technologies to reach four gold standards set for the “$1000 Genome” while the second-generation sequencing technologies are bringing about a revolution in life sciences, particularly in genome sequencing-based personalized medicine. Both of protein and solid-state nanopores have been extensively investigated for a series of issues, from detection of ionic current blockage to field-effect-transistor (FET) sensors. A newly released protein nanopore sequencer has shown encouraging potential that nanopore sequencing will ultimately fulfill the gold standards. In this review, we address advances, challenges, and possible solutions of nanopore sequencing according to these standards.
PMCID: PMC4285804  PMID: 25610451
gold standards; third-generation sequencing; nanopore sequencing; ionic current blockage; DNA ratcheting; sequencing by tunneling; multiplexing detection; field-effect-transistor (FET) nanopore sensor
12.  L-type Ca2+ currents at CA1 synapses, but not CA3 or dentate granule neuron synapses, are increased in 3xTgAD mice in an age-dependent manner 
Neurobiology of aging  2013;35(1):10.1016/j.neurobiolaging.2013.07.007.
Abnormal neuronal excitability and impaired synaptic plasticity might occur before the degeneration and death of neurons in Alzheimer’s disease (AD). To elucidate potential biophysical alterations underlying aberrant neuronal network activity in AD, we performed whole-cell patch clamp analyses of L-type (nifedipine-sensitive) Ca2+ currents (L-VGCC), 4–aminopyridine-sensitive K+ currents, and AMPA (2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propanoic acid) and NMDA (N-methyl-D-aspartate) currents in CA1, CA3, and dentate granule neurons in hippocampal slices from young, middle-age, and old 3xTgAD mice and age-matched wild type mice. 3xTgAD mice develop progressive widespread accumulation of amyloid b-peptide, and selective hyperphosphorylated tau pathology in hippocampal CA1 neurons, which are associated with cognitive deficits, but independent of overt neuronal degeneration. An age-related elevation of L-type Ca2+ channel current density occurred in CA1 neurons in 3xTgAD mice, but not in wild type mice, with the magnitude being significantly greater in older 3xTgAD mice. The NMDA current was also significantly elevated in CA1 neurons of old 3xTgAD mice compared with in old wild type mice. There were no differences in the amplitude of K+ or AMPA currents in CA1 neurons of 3xTgAD mice compared with wild type mice at any age. There were no significant differences in Ca2+, K+, AMPA, or NMDA currents in CA3 and dentate neurons from 3xTgAD mice compared with wild type mice at any age. Our results reveal an age-related increase of L-VGCC density in CA1 neurons, but not in CA3 or dentate granule neurons, of 3xTgAD mice. These findings suggest a potential contribution of altered L-VGCC to the selective vulnerability of CA1 neurons to tau pathology in the 3xTgAD mice and to their degeneration in AD patients.
PMCID: PMC3864587  PMID: 23932880
3xTgAD mice; Aging; L-type Ca2+ currents; CA1
13.  M-CSF cooperating with NFκB induces macrophage transformation from M1 to M2 by upregulating c-Jun 
Cancer Biology & Therapy  2013;15(1):99-107.
Increasing evidence suggests tumor-associated macrophages (TAMs) are polarized M2 subtype of macrophage that exerts pro-tumor effects and promote the malignancy of some cancers, but the concrete mechanism is not well defined. Our previous research exhibited that proto-oncogene AP-1 regulated IL-6 expression in macrophages and promoted the formation of M2 macrophages. In this study, we investigate whether extra-cellular stimulus M-CSF help this process or nuclear factor NFκB has a synergistic role in the activation state of polarized M2 subtype of macrophage. RAW 264.7 macrophage and 4T1 mouse breast cancer cells were co-cultured to reconstruct tumor microenvironment. Being co-cultured with 4T1 or its supernatant, the expression of c-Jun, the member of AP-1 family, has a dramatically increase both on the level of gene and on the protein in RAW 264.7 macrophages, but the expression of c-Fos does not increase neither on the level of gene nor on the protein. After co-cultured with 4T1, RAW 264.7 has a higher consumption of M-CSF than RAW 264.7 macrophages alone. With the stimulation of M-CSF, the mRNA of c-Jun increased significantly, but decreased remarkably after adding the anti-M-CSF. And at the same time, p50, the member of NFκB family, has a similar tendency to c-Jun. WB results suggest that with the stimulation of M-CSF, p-Jun in nuclear increases heavily but decreases after the neutralizing antibody added. Coimmunoprecipitation and immunoblotting techniques confirmed that c-Jun and p50 NFκB coprecipitated, and c-Jun protein expression is properly enhanced with rM-CSF effect. In conclusion, M-CSF induces macrophage transformation by upregulating c-Jun with a certain synergy of NFκB. Our study may present a novel therapeutic strategy against cancer.
PMCID: PMC3938528  PMID: 24100343
M-CSF; NFκB; c-Jun; co-culture; transformation
15.  Interleukin-34 Restores Blood–Brain Barrier Integrity by Upregulating Tight Junction Proteins in Endothelial Cells 
PLoS ONE  2014;9(12):e115981.
Interleukin-34 (IL-34) is a newly discovered cytokine as an additional ligand for colony stimulating factor-1 receptor (CSF1R), and its functions are expected to overlap with colony stimulating factor-1/macrophage-colony stimulating factor. We have previously shown that the IL-34 is primarily produced by neurons in the central nervous system (CNS) and induces proliferation and neuroprotective properties of microglia which express CSF1R. However, the functions of IL-34 in the CNS are still elucidative. Here we show that CNS capillary endothelial cells also express CSF1R. IL-34 protected blood–brain barrier integrity by restored expression levels of tight junction proteins, which were downregulated by pro-inflammatory cytokines. The novel function of IL-34 on the blood–brain barrier may give us a clue for new therapeutic strategies in neuroinflammatory and neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease.
PMCID: PMC4275171  PMID: 25535736
16.  Effect of luteinizing hormone-induced prohibitin and matrix metalloproteinases on ovarian epithelial tumor cell proliferation 
Recent studies have suggested that elevated gonadotropins contribute to ovarian epithelial tumor (OET) cell proliferation. However, the cellular effects of luteinizing hormone, a member of gonadotropins, on OET proliferation are controversial. Our previous work showed that luteinizing hormone has no effect on cell proliferation, but the molecular mechanism of such finding remains to be clarified. Considering that the cell growth in various types of tumors has been associated with regulations of prohibitin and matrix metalloproteinases, we aim to investigate a possible regulatory role of luteinizing hormone on prohibitin and matrix metalloproteinases to determine the roles of these molecules in OET proliferation. We found that LH stimulation resulted in a dose-dependent expression of prohibitin and MMPs and time-dependent phosphorylations of ERK and AKT. Blocking MAPK or PI3K/AKT signaling could attenuate LH-induced prohibitin and MMPs expression. Additionally, the depletion of prohibitin reduced the level of MMPs expression, and increased prohibitin expression abolished the positive effect of LH-induced MMP-9 on cellular growth. Therefore, we conclude that LH is able to up-regulate both prohibitin and MMP-9 in OET cells without the cellular growth effect due to opposing biologic functions for cell proliferation between these two molecules. The opposing cellular growth function between prohibitin and MMP-9 is a novel finding. Regulation of either molecule may be useful for future targeted therapy for ovarian epithelial cancers.
PMCID: PMC4300715  PMID: 25628924
Prohibitin; MMP-2; MMP-9; LH; proliferation
17.  MicroRNA-19a promotes glioma cell growth by repressing LRIG1 
Growing evidence indicates that deregulation of miRNAs contributes to the development of glioma. In present study, we found that the level of miRNA-19a was significantly elevated in glioma tissues and cell lines. Moreover, down-regulation of miRNA-19a dramatically repressed glioma cell growth in vitro and in vivo. Meanwhile, the expression of LRIG1, a tumor suppressor in glioma, was increased following miRNA-19a knockdown. Furthermore, luciferase reporter assay confirmed that LRIG1 was a direct target of miRNA-19a. In addition, silencing of LRIG1 could reverse the suppressive effect of miRNA-19a inhibitor. Taken together, our results demonstrated that down-regulation of miRNA-19a could suppress the growth of glioma cells, at least in part, through up-regulating LRIG1.
PMCID: PMC4307453  PMID: 25664006
miRNA-19a; LRIG1; glioma; proliferation
18.  A cross-validation deletion–substitution–addition model selection algorithm: Application to marginal structural models 
The cross-validation deletion–substitution–addition (cvDSA) algorithm is based on data-adaptive estimation methodology to select and estimate marginal structural models (MSMs) for point treatment studies as well as models for conditional means where the outcome is continuous or binary. The algorithm builds and selects models based on user-defined criteria for model selection, and utilizes a loss function-based estimation procedure to distinguish between different model fits. In addition, the algorithm selects models based on cross-validation methodology to avoid “over-fitting” data. The cvDSA routine is an R software package available for download. An alternative R-package (DSA) based on the same principles as the cvDSA routine (i.e., cross-validation, loss function), but one that is faster and with additional refinements for selection and estimation of conditional means, is also available for download. Analyses of real and simulated data were conducted to demonstrate the use of these algorithms, and to compare MSMs where the causal effects were assumed (i.e., investigator-defined), with MSMs selected by the cvDSA. The package was used also to select models for the nuisance parameter (treatment) model to estimate the MSM parameters with inverse-probability of treatment weight (IPTW) estimation. Other estimation procedures (i.e., G-computation and double robust IPTW) are available also with the package.
PMCID: PMC4259156  PMID: 25505354
Cross-validation; Machine learning; Marginal structural models; Lung function; Cardiovascular mortality
19.  Spirometry Use among Older Adults with Chronic Obstructive Pulmonary Disease: 1999–2008 
Rationale: Clinical practice guidelines recommend spirometry to diagnose chronic obstructive pulmonary disease (COPD) and facilitate management. National trends in spirometry use in older adults with newly diagnosed COPD are not known.
Objectives: To examine the rate and beneficiary characteristics associated with spirometry use in subjects with newly diagnosed COPD between 1999 and 2008.
Methods: We examined newly diagnosed beneficiaries with COPD using a 5% Medicare population from 1999 to 2008. A new COPD diagnosis required two outpatient visits or one hospitalization with primary International Classification of Diseases, 9th edition code 491.xx, 492.xx, or 496 occurring at least 30 days apart with none in the prior 12 months. The primary measurement was spirometry performed within 365 days (±) of the first claim with a COPD diagnosis.
Measurements and Main Results: Between 1999 and 2008, 64,985 subjects were newly diagnosed with COPD. Of these, 35,739 (55%) had spirometry performed within 1 year before or after the initial diagnosis of COPD. Spirometry use increased from 51.3% in 1999 to 58.3% in 2008 (P < 0.001). Subjects with younger age, men, whites, those with higher socioeconomic status, and those with a greater number of comorbidities were more likely to have spirometry. In a multivariable analysis, compared with 1999, subjects diagnosed in 2008 had 10% higher odds (odds ratio, 1.10; 95% confidence interval, 1.06–1.13) of having spirometry performed.
Conclusions: Despite an increase in the use of spirometry over time in newly diagnosed older adults with COPD, spirometry use remains low. Clinical practice guidelines and educational efforts should focus on increasing the use of spirometry to diagnose and manage COPD.
PMCID: PMC3960963  PMID: 24053440
spirometry; chronic obstructive pulmonary disease; Medicare; older adults; pulmonary function test
20.  Macrophage and NK-mediated Killing of Precursor-B Acute Lymphoblastic Leukemia Cells Targeted with a-Fucosylated Anti-CD19 Humanized Antibodies 
Leukemia  2013;27(6):1263-1274.
This work reports the tumoricidal effects of a novel investigational humanized anti-CD19 monoclonal antibody (Medi-551). An a-fucosylated antibody with increased affinity for human FcγRIIIA, Medi-551 is shown to mediate both antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP). Medi-551/CD19 complexes internalize slowly (>5 hrs) and thus remain accessible to effector cells for prolonged periods. We evaluated in vitro ADCC and ADCP activities of primary human natural killer (NK) cells and macrophages against pre-B ALL cell lines and pediatric patient blasts. Fluorescent imaging studies document immunological synapses formed between anti-CD19-bound target leukemia cells and effector cells and capture the kinetics of both NK-mediated killing and macrophage phagocytosis. Genetic polymorphisms in FcγRIIIA-158F/V modulate in vitro activities of effector cells, with FcγRIIIA-158V homo- or heterozygotes showing the strongest activity. Medi-551 treatment of SCID mice engrafted with human pre-B cells led to prolonged animal survival and markedly reduced disease burden in blood, liver and bone marrow. These data show that anti-CD19 antibodies effectively recruit immune cells to pre-B ALL cells and support a move forward to early phase trials in this disease.
PMCID: PMC4249624  PMID: 23307031
leukemia; pre-B ALL; ADCC; ADCP; targeted therapies; monoclonal antibodies
21.  Berberine derivatives reduce atherosclerotic plaque size and vulnerability in apoE−/− mice 
Background and aims
Our previous in vitro and clinical work has demonstrated anti-inflammatory effects of berberine (BBR), but the clinical application of BBR is limited by its poor bioavailability. Derivatives of BBR have been suggested to have enhanced bioavailability compared to BBR. In this study, we tested whether BBR derivatives, compared with BBR, had superior beneficial effects on atherosclerotic plaques in apoE−/− mice, and defined possible molecular mechanisms underlying such effects.
Macrophages were pretreated with BBR and its derivatives, dihydroberberine (dhBBR) and 8,8-dimethyldihydroberberine (Di-MeBBR), before incubation with oxLDL. Cell surface EMMPRIN expression was measured by flow cytometry and Western blotting, and phospho-(p)-p38, p-JNK, nuclear NFκB p65, and phospho-p65 were measured by Western blotting. ApoE−/− mice fed with the Western diet for 16 weeks were treated with BBR, dhBBR and Di-MeBBR 16 weeks. Aortic atherosclerotic lesion size, plaque matrix proteins, and EMMPRIN and other inflammatory factors were measured using Oil Red O Staining, Masson’s trichromestaining and immunohistochemical staining and real-time PCR.
Compared with BBR, dhBBR and Di-MeBBR significantly reduced EMMPRIN expression, which was associated with a greater inhibition of p-p38, p-JNK, nuclear NFκB p65 and phospho-p65 induced by oxLDL in macrophages. dhBBR and Di-MeBBR, but not BBR, reduced atherosclerotic plaque size and improved plaque stability indicated by increased α-smooth muscle actin and collagen content, and thicker fibrous caps. dhBBR and Di-MeBBR reduced expression of EMMPRIN, CD68, and NFκB p65, and Di-MeBBR also reduced expression of matrix metalloproteinase-9, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 in aortic plaques.
These results have demonstrated that BBR derivatives, dhBBR and Di-MeBBR, are superior to BBR in inhibiting inflammation and reducing plaque size and vulnerability.
PMCID: PMC4261588  PMID: 25425200
Berberine derivatives; EMMPRIN; Inflammation; Atherosclerosis; Plaque stability
22.  Flexibility and Symmetry of Prokaryotic Genome Rearrangement Reveal Lineage-Associated Core-Gene-Defined Genome Organizational Frameworks 
mBio  2014;5(6):e01867-14.
The prokaryotic pangenome partitions genes into core and dispensable genes. The order of core genes, albeit assumed to be stable under selection in general, is frequently interrupted by horizontal gene transfer and rearrangement, but how a core-gene-defined genome maintains its stability or flexibility remains to be investigated. Based on data from 30 species, including 425 genomes from six phyla, we grouped core genes into syntenic blocks in the context of a pangenome according to their stability across multiple isolates. A subset of the core genes, often species specific and lineage associated, formed a core-gene-defined genome organizational framework (cGOF). Such cGOFs are either single segmental (one-third of the species analyzed) or multisegmental (the rest). Multisegment cGOFs were further classified into symmetric or asymmetric according to segment orientations toward the origin-terminus axis. The cGOFs in Gram-positive species are exclusively symmetric and often reversible in orientation, as opposed to those of the Gram-negative bacteria, which are all asymmetric and irreversible. Meanwhile, all species showing strong strand-biased gene distribution contain symmetric cGOFs and often specific DnaE (α subunit of DNA polymerase III) isoforms. Furthermore, functional evaluations revealed that cGOF genes are hub associated with regard to cellular activities, and the stability of cGOF provides efficient indexes for scaffold orientation as demonstrated by assembling virtual and empirical genome drafts. cGOFs show species specificity, and the symmetry of multisegmental cGOFs is conserved among taxa and constrained by DNA polymerase-centric strand-biased gene distribution. The definition of species-specific cGOFs provides powerful guidance for genome assembly and other structure-based analysis.
Prokaryotic genomes are frequently interrupted by horizontal gene transfer (HGT) and rearrangement. To know whether there is a set of genes not only conserved in position among isolates but also functionally essential for a given species and to further evaluate the stability or flexibility of such genome structures across lineages are of importance. Based on a large number of multi-isolate pangenomic data, our analysis reveals that a subset of core genes is organized into a core-gene-defined genome organizational framework, or cGOF. Furthermore, the lineage-associated cGOFs among Gram-positive and Gram-negative bacteria behave differently: the former, composed of 2 to 4 segments, have their fragments symmetrically rearranged around the origin-terminus axis, whereas the latter show more complex segmentation and are partitioned asymmetrically into chromosomal structures. The definition of cGOFs provides new insights into prokaryotic genome organization and efficient guidance for genome assembly and analysis.
PMCID: PMC4251990  PMID: 25425232
23.  Dicer Is Required for Maintenance of Adult Pancreatic Acinar Cell Identity and Plays a Role in Kras-Driven Pancreatic Neoplasia 
PLoS ONE  2014;9(11):e113127.
The role of miRNA processing in the maintenance of adult pancreatic acinar cell identity and during the initiation and progression of pancreatic neoplasia has not been studied in detail. In this work, we deleted Dicer specifically in adult pancreatic acinar cells, with or without simultaneous activation of oncogenic Kras. We found that Dicer is essential for the maintenance of acinar cell identity. Acinar cells lacking Dicer showed increased plasticity, as evidenced by loss of polarity, initiation of epithelial-to-mesenchymal transition (EMT) and acinar-to-ductal metaplasia (ADM). In the context of oncogenic Kras activation, the initiation of ADM and pancreatic intraepithelial neoplasia (PanIN) were both highly sensitive to Dicer gene dosage. Homozygous Dicer deletion accelerated the formation of ADM but not PanIN. In contrast, heterozygous Dicer deletion accelerated PanIN initiation, revealing complex roles for Dicer in the regulation of both normal and neoplastic pancreatic epithelial identity.
PMCID: PMC4236134  PMID: 25405615
24.  Benign giant-cell tumor of the common bile duct: A case report 
World Journal of Gastroenterology : WJG  2014;20(41):15448-15453.
Primary giant-cell tumors rarely arise in the common bile duct. We herein report a case of primary giant-cell tumor of the common bile duct. The patient was an 81-year-old male who was diagnosed with a well-defined 1.2-cm mass projecting into the lumen of the middle common bile duct. Excision of the gallbladder and extrahepatic bile duct and a Roux-en-Y cholangiojejunostomy were performed. Histologically, the tumor had no association with carcinomas of epithelial origin and was similar to giant-cell tumors of the bone. The tumor consisted of a mixture of mononuclear and multinucleated osteoclast-like giant cells. The mononuclear cells showed no atypical features, and their nuclei were similar to those of the multinucleated giant cells. CD68 was expressed on the mononuclear and multinucleated osteoclast-like giant cells, whereas CD163 immunoreactivity was restricted to the mononuclear cells. Six months after the operation, the patient was still alive and had no recurrence. The interest of this case lies in the rarity of this entity, the difficulty of preoperative diagnosis, and this tumor’s possible confusion with other malignant tumors.
PMCID: PMC4223279  PMID: 25386094
Giant-cell tumor; Common bile duct; CD163; Surgical resection
25.  Unsupervised Deconvolution of Dynamic Imaging Reveals Intratumor Vascular Heterogeneity and Repopulation Dynamics 
PLoS ONE  2014;9(11):e112143.
With the existence of biologically distinctive malignant cells originated within the same tumor, intratumor functional heterogeneity is present in many cancers and is often manifested by the intermingled vascular compartments with distinct pharmacokinetics. However, intratumor vascular heterogeneity cannot be resolved directly by most in vivo dynamic imaging. We developed multi-tissue compartment modeling (MTCM), a completely unsupervised method of deconvoluting dynamic imaging series from heterogeneous tumors that can improve vascular characterization in many biological contexts. Applying MTCM to dynamic contrast-enhanced magnetic resonance imaging of breast cancers revealed characteristic intratumor vascular heterogeneity and therapeutic responses that were otherwise undetectable. MTCM is readily applicable to other dynamic imaging modalities for studying intratumor functional and phenotypic heterogeneity, together with a variety of foreseeable applications in the clinic.
PMCID: PMC4224420  PMID: 25379705

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