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1.
Acta Virol ; 64(4): 470-479, 2020.
Article in English | MEDLINE | ID: mdl-33151741

ABSTRACT

The methods for expansion of human cytomegalovirus (HCMV)-specific T lymphocytes are limited due to the complex culture process, long culture duration, and human leukocyte antigen (HLA) restriction. Here, we report that in vitro stimulation with pp65 kDa phosphoprotein (pp65)-derived overlapping synthetic peptides rapidly generates large numbers of HCMV-specific cytotoxic T lymphocytes from peripheral blood mononuclear cells (PBMCs) regardless of HLA type. Treatment of PBMCs from healthy volunteers expressing HLA-A*02:01 or HLA-A*24:02 with 138 pp65 overlapping peptides (OLP) resulted in an expansion of HCMV pp65 NLVPMVATV (NLV) pentamer-specific CD8+ T lymphocytes that expressed interferon (IFN)-γ, but the pp65 NLV peptide did not generate HCMV-specific CD8+ T lymphocytes in PBMCs obtained from an HLA-A*24:02 donor due to HLA restriction. The OLP-induced T lymphocytes specific for HCMV derived from PBMCs of HLA-A*02:01- and HLA-A*24:02-expressing donors showed effective cytolytic responses against target cells loaded with OLP or the NLV epitope, but pp65 NLV peptide-induced T lymphocytes did not. Phenotypic analyses demonstrated that OLP increased the frequency of CD3+ CD8+ cells, but not CD3+ CD4+, CD14+, or CD56+ cells, in donor PBMCs. Thus, this study provides evidence that in vitro stimulation with OLP efficiently generates sufficient numbers of HCMV pp65-specific cytotoxic T lymphocytes for adoptive cell therapy. Keywords: human cytomegalovirus; cytotoxic T lymphocyte; overlapping peptides; pp65; cytotoxicity.


Subject(s)
Cytomegalovirus Infections/immunology , Peptides/immunology , T-Lymphocytes, Cytotoxic/virology , Viral Matrix Proteins/immunology , Cytomegalovirus , HLA-A Antigens , Humans , Leukocytes, Mononuclear , Phosphoproteins/immunology
2.
Astrobiology ; 19(3): 369-386, 2019 03.
Article in English | MEDLINE | ID: mdl-30840503

ABSTRACT

The limitations placed upon human explorers on the surface of Mars will necessitate a methodology for scientific exploration that is different from standard approaches to terrestrial fieldwork and prior crewed exploration of the Moon. In particular, the data transmission limitations and communication latency between Earth and Mars create a unique situation for surface crew in contact with a terrestrial science team. The BASALT research program simulated a series of extravehicular activities (EVAs) in Mars analog terrains under various Mars-relevant bandwidth and latency conditions to investigate how best to approach this problem. Here we discuss tactical decision-making under these conditions, that is, how the crew on Mars interacts with a team of scientists and support personnel on Earth to collect samples of maximum scientific interest. We describe the strategies, protocols, and tools tested in BASALT EVAs and give recommendations on how best to conduct human exploration of Mars with support from Earth-based scientists. We find that even with scientists supporting them, the crew performing the exploration must be trained in the appropriate scientific disciplines in order to provide the terrestrial scientists with enough information to make decisions, but that with appropriate planning and structure, and tools such as a "dynamic leaderboard," terrestrial scientists can add scientific value to an EVA, even under Mars communication latency.


Subject(s)
Astronauts/psychology , Communication , Decision Making , Mars , Satellite Communications , Earth, Planet , Exobiology/methods , Extraterrestrial Environment , Humans , Spacecraft , Time Factors
3.
Astrobiology ; 19(3): 321-346, 2019 03.
Article in English | MEDLINE | ID: mdl-30840507

ABSTRACT

The Biologic Analog Science Associated with Lava Terrains (BASALT) research project is investigating tools, techniques, and strategies for conducting Mars scientific exploration extravehicular activity (EVA). This has been accomplished through three science-driven terrestrial field tests (BASALT-1, BASALT-2, and BASALT-3) during which the iterative development, testing, assessment, and refinement of concepts of operations (ConOps) and capabilities were conducted. ConOps are the instantiation of operational design elements that guide the organization and flow of personnel, communication, hardware, software, and data products to enable a mission concept. Capabilities include the hardware, software, data products, and protocols that comprise and enable the ConOps. This paper describes the simulation quality and acceptability of the Mars-forward ConOps evaluated during BASALT-2. It also presents the level of mission enhancement and acceptability of the associated Mars-forward capabilities. Together, these results inform science operations for human planetary exploration.


Subject(s)
Exobiology/methods , Extravehicular Activity , Mars , Operations Research , Space Simulation/methods , Exobiology/instrumentation , Humans , Space Simulation/instrumentation
4.
Astrobiology ; 19(3): 387-400, 2019 03.
Article in English | MEDLINE | ID: mdl-30840508

ABSTRACT

During the BASALT research program, real (nonsimulated) geological and biological science was accomplished through a series of extravehicular activities (EVAs) under simulated Mars mission conditions. These EVAs were supported by a Mission Support Center (MSC) that included an on-site, colocated Science Support Team (SST). The SST was composed of scientists from a variety of disciplines and operations researchers who provided scientific and technical expertise to the crew while each EVA was being conducted (intra-EVA). SST management and organization developed under operational conditions that included Mars-like communication latencies, bandwidth constraints, and EVA plans that were infused with Mars analog field science objectives. This paper focuses on the SST workspace considerations such as science team roles, physical layout, communication interactions, operational techniques, and work support technology. Over the course of BASALT field deployments to Idaho and Hawai'i, the SST team made several changes of note to increase both productivity and efficiency. For example, new roles were added for more effective management of technical discussions, and the layout of the SST workspace evolved multiple times during the deployments. SST members' reflexive adjustments resulted in a layout that prioritized face-to-face discussions over face-to-data displays, highlighting the importance of interpersonal communication during SST decision-making. In tandem with these workspace adjustments, a range of operational techniques were developed to help the SST manage discussions and information flow under time pressure.


Subject(s)
Astronauts/psychology , Extravehicular Activity , Mars , Space Simulation/methods , Communication , Decision Making , Decision Support Techniques , Efficiency , Hawaii , Humans , Idaho , Interpersonal Relations , Satellite Communications , Space Simulation/psychology
5.
Nutr Metab Cardiovasc Dis ; 29(4): 360-366, 2019 04.
Article in English | MEDLINE | ID: mdl-30782509

ABSTRACT

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is a cluster of multiple risk factors including central obesity that may lead to cardiac damage and cardiovascular events. We investigated whether visceral obesity induces cardiac structural and functional remodeling independently from central obesity and other risk factors in subjects with suspected MetS. METHODS AND RESULTS: We studied 229 participants with suspected MetS. Visceral fat area (VFA) was measured by bioelectrical impedance analysis. Left ventricular (LV) mass index, early diastolic velocity of mitral annulus (e'), and LV global longitudinal strain (GLS) were measured by echocardiography. Subjects were categorized into high and low VFA group (VFAh and VFAl). MetS was more prevalent in the VFAh than in the VFAl (p = 0.004). The VFAh had a higher waist circumference (WC) than the VFAl (p < 0.001). LV mass index was higher, but e' and GLS were lower in the VFAh than in VFAl (all p < 0.05). VFA was well correlated with blood pressure, fasting blood glucose, triglyceride, high-sensitivity C-reactive protein and adiponectin (all p < 0.05). VFA was correlated to LV mass index, e', and GLS (all p < 0.05) and was independently associated with GLS after adjustment for other risk factors, including WC (p = 0.005). CONCLUSIONS: Visceral obesity assessed by VFA was well correlated with parameters of MetS. Visceral obesity, but not central obesity measured by WC, was independently associated with structural and functional cardiac remodeling in subjects with suspected MetS. It suggests that visceral obesity should be considered as an important risk factor for cardiac damage in dysmetabolic subjects. TRIAL REGISTRATION: NCT02077530 (date of registration: November 1, 2013).


Subject(s)
Abdominal Fat/physiopathology , Adiposity , Cardiovascular Diseases/physiopathology , Intra-Abdominal Fat/physiopathology , Metabolic Syndrome/physiopathology , Obesity, Abdominal/physiopathology , Ventricular Function, Left , Ventricular Remodeling , Abdominal Fat/diagnostic imaging , Abdominal Fat/metabolism , Biomarkers/blood , Cardiovascular Diseases/blood , Cardiovascular Diseases/diagnostic imaging , Echocardiography, Doppler, Pulsed , Electric Impedance , Female , Humans , Intra-Abdominal Fat/diagnostic imaging , Intra-Abdominal Fat/metabolism , Male , Metabolic Syndrome/blood , Metabolic Syndrome/diagnostic imaging , Middle Aged , Obesity, Abdominal/blood , Obesity, Abdominal/diagnostic imaging , Prognosis , Prospective Studies , Risk Factors , Tomography, X-Ray Computed , Waist Circumference
6.
Public Health ; 139: 178-182, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27406975

ABSTRACT

OBJECTIVES: Metabolic syndrome (MS), as a precursor of diabetes mellitus (DM) and cardiovascular disease, is increasing steadily worldwide. We examined the preventive effects of lifestyle intervention on the occurrence of DM and acute myocardial infarction (AMI) in MS. STUDY DESIGN: Observational study on disease occurrence after lifestyle intervention. METHODS: The lifestyle intervention was administered to subjects with MS participating in a metropolitan lifestyle intervention program for 1 year. The same numbers of non-participating age- and sex-matched subjects with MS were randomly extracted from national health examination data. After intervention or examination, new occurrences of hypertension, DM, and AMI were identified through the national health insurance claims data during 1 year. For DM and AMI, multivariate logistic regression analysis for the factors affecting each disease was performed. RESULTS: In the intervention group and the control group (14,918 in each group), the occurrence of hypertension was 555 (6.07%) and 751 (8.33%), the occurrence of DM was 324 (2.55%) and 488 (3.89%), the occurrence of dyslipidemia was 321 (2.59%) and 373 (2.72%), and the occurrence of AMI was 13 (0.09%) and 26 (0.17%), respectively. In multivariate logistic regression analysis, adjusted odds ratios for intervention were 0.752 (95% confidence interval [CI]: 0.644-0.879) and 0.499 (95% CI: 0.251-0.992) for DM and AMI, respectively, indicating that lifestyle intervention has a preventive effect. CONCLUSIONS: Lifestyle intervention in MS has preventive effects on the occurrence of DM and AMI, and long-term follow-up is needed to evaluate these preventive effects in more detail.


Subject(s)
Diabetes Mellitus/epidemiology , Life Style , Metabolic Syndrome/epidemiology , Myocardial Infarction/epidemiology , Preventive Health Services , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Program Evaluation , Republic of Korea/epidemiology
8.
Geobiology ; 13(4): 357-72, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25809931

ABSTRACT

Modern microbialites in Pavilion Lake, BC, provide an analog for ancient non-stromatolitic microbialites that formed from in situ mineralization. Because Pavilion microbialites are mineralizing under the influence of microbial communities, they provide insights into how biological processes influence microbialite microfabrics and mesostructures. Hemispherical nodules and micrite-microbial crusts are two mesostructures within Pavilion microbialites that are directly associated with photosynthetic communities. Both filamentous cyanobacteria in hemispherical nodules and branching filamentous green algae in micrite-microbial crusts were associated with calcite precipitation at microbialite surfaces and with characteristic microfabrics in the lithified microbialite. Hemispherical nodules formed at microbialite surfaces when calcite precipitated around filamentous cyanobacteria with a radial growth habit. The radial filament pattern was preserved within the microbialite to varying degrees. Some subsurface nodules contained well-defined filaments, whereas others contained only dispersed organic inclusions. Variation in filament preservation is interpreted to reflect differences in timing and amount of carbonate precipitation relative to heterotrophic decay, with more defined filaments reflecting greater lithification prior to degradation than more diffuse filaments. Micrite-microbial crusts produce the second suite of microfabrics and form in association with filamentous green algae oriented perpendicular to the microbialite surface. Some crusts include calcified filaments, whereas others contained voids that reflect the filamentous community in shape, size, and distribution. Pavilion microbialites demonstrate that microfabric variation can reflect differences in lithification processes and microbial metabolisms as well as microbial community morphology and organization. Even when the morphology of individual filaments or cells is not well preserved, the microbial growth habit can be captured in mesoscale microbialite structures. These results suggest that when petrographic preservation is extremely good, ancient microbialite growth structures and microfabrics can be interpreted in the context of variation in community organization, community composition, and lithification history. Even in the absence of distinct microbial microfabrics, mesostructures can capture microbial community morphology.


Subject(s)
Carbonates/chemistry , Chlorophyta/growth & development , Cyanobacteria/growth & development , Geologic Sediments/microbiology , Lakes/microbiology , British Columbia , Chlorophyta/ultrastructure , Cyanobacteria/ultrastructure , Fossils/anatomy & histology , Fossils/microbiology , Microscopy, Electron, Scanning
9.
Cell Death Discov ; 1: 15011, 2015.
Article in English | MEDLINE | ID: mdl-27551446

ABSTRACT

Recently, γ-synuclein (SNCG), which is also known as breast cancer-specific gene-1, has been demonstrated to be an adverse and aggressive marker in breast cancer. In our previous study, SNCG was significantly upregulated in irradiated human breast cancer cells. The aim of this study was to investigate whether radiation-induced, tumor-derived SNCG can influence dendritic cell (DC) function in immune systems. The phenotypical and functional changes of DCs in the presence or absence of SNCG were investigated by FACS analysis, ELISA, and real-time PCR. The ability of SNCG-treated DCs to influence T cells was also examined by coculturing with T cells. The treatment of DCs with SNCG protein inhibited the surface expression of the co-stimulatory molecules CD40 and CD86, and decreased the mRNA levels of pro-inflammatory cytokines. The SNCG-treated DCs inhibited T-cell proliferation slightly, but distinctively increased the population of regulatory T cells. In addition, the production of TGF-ß from T cells was significantly increased when they were cocultured with SNCG-treated DCs. Taken together, these results demonstrate that tumor-derived SNCG contributes to immunosuppressive effects via the inhibition of DC differentiation and activation, thus making it a potential target for cancer treatment.

10.
J Eur Acad Dermatol Venereol ; 29(8): 1539-44, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25491106

ABSTRACT

BACKGROUND: Fixed drug eruptions (FDE) are most commonly caused by antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs). The list of causative drugs changes with time and prescribing patterns but there has been no recent data on FDE seen in an outpatient setting in Singapore. OBJECTIVE: We aimed to evaluate the epidemiology, clinical features and causative drugs in patients with FDE in Singapore. METHODS: We performed a retrospective chart review of all patients seen with suspected FDE in the National Skin Centre, Singapore between 2008 and 2012. Using criteria adapted from the WHO-UMC causality assessment criteria, patients were classified into categories of definite (confirmed with patch test or drug provocation test), probable (causative drug identified based on patient's history), possible (clinically consistent but unable to identify causative drug) or unlikely FDE. RESULTS: We reviewed the charts of 126 patients who were seen for suspected FDE. Ten patients (7.0%) were classified as having definite FDE, 52 patients (41.3%) probable FDE, 61 patients (48.4%) possible FDE and three patients (2.4%) unlikely FDE. Clinical features were similar to those described in previous studies. Among the 62 patients with definite or probable FDE, etoricoxib was the most common cause (24 patients, 38.7%). Other common causes included paracetamol, other NSAIDs and doxycycline. Antihistamines caused FDE in three patients. CONCLUSION: Etoricoxib was the most frequent cause of FDE in our study. Other NSAIDs, paracetamol and doxycycline remain common causes of FDE but we caution that antihistamines, such as cetirizine, should also be considered.


Subject(s)
Drug Eruptions , Adolescent , Adult , Aged , Child , Child, Preschool , Drug Eruptions/diagnosis , Drug Eruptions/epidemiology , Drug Eruptions/etiology , Female , Humans , Male , Middle Aged , Retrospective Studies , Singapore/epidemiology , Young Adult
11.
Cell Death Dis ; 5: e1432, 2014 Oct 02.
Article in English | MEDLINE | ID: mdl-25275593

ABSTRACT

Peroxisome proliferator-activated receptors (PPARs) inhibit lipopolysaccharide (LPS)-primed release of high mobility group box 1 (HMGB1), a late proinflammatory mediator, but the underlying molecular mechanism is not completely understood. In this study, we demonstrated that the inhibition of HMGB1 release by PPAR-δ and -γ is associated with the deacetylase activity of SIRT1. Ligand-activated PPAR-δ and -γ inhibited LPS-primed release of HMGB1, concomitant with elevation in SIRT1 expression and promoter activity. These effects were significantly reduced in the presence of small interfering (si)RNAs against PPAR, indicating that PPAR-δ and -γ are involved in both HMGB1 release and SIRT1 expression. In addition, modulation of SIRT1 expression and activity by siRNA or chemicals correspondingly influenced the effects of PPARs on HMGB1 release, suggesting a mechanism in which SIRT1 modulates HMGB1 release. Furthermore, we showed for the first time that HMGB1 acetylated in response to LPS or p300/CBP-associated factor (PCAF) is an effective substrate for SIRT1, and that deacetylation of HMGB1 is responsible for blockade of HMGB1 release in macrophages. Finally, acetylation of HMGB1 was elevated in mouse embryonic fibroblasts from SIRT1-knockout mice, whereas this increase was completely reversed by ectopic expression of SIRT1. These results indicate that PPAR-mediated upregulation of SIRT1 modulates the status of HMGB1 acetylation, which, in turn, has a critical role in the cellular response to inflammation through deacetylation-mediated regulation of HMGB1 release.


Subject(s)
HMGB1 Protein/metabolism , Lipopolysaccharides/metabolism , PPAR delta/metabolism , PPAR gamma/metabolism , Sirtuin 1/genetics , Animals , Cell Line , Down-Regulation , HMGB1 Protein/genetics , Humans , Macrophages/enzymology , Macrophages/metabolism , Mice , Mice, Knockout , PPAR delta/genetics , PPAR gamma/genetics , Sirtuin 1/metabolism , Up-Regulation , p300-CBP Transcription Factors/genetics , p300-CBP Transcription Factors/metabolism
12.
Int J Parasitol ; 44(5): 291-8, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24583111

ABSTRACT

Traditional healers in Sarawak, Malaysia, use plants such as Picria fel-terrae, Linariantha bicolor and Lansium domesticum to treat gastrointestinal infections. This study aimed to test whether their nematocidal activities could be confirmed in vitro using highly standardised Caenorhabditis elegans models. We applied eight different ethanol solubilised plant extracts and two commercial anthelmintic drugs to larval and adult stages of C. elegans in vitro. Seven C. elegans strains were evaluated, one wild type and six strains with GFP-tagged stress response pathways to help characterise and compare the pathways affected by plant extracts. Our in vitro screen confirmed that both of the commercial anthelmintic drugs and five of the eight traditionally used plant extracts had significant nematocidal activity against both larval and adult C. elegans. The most effective extracts were from P. fel-terrae. The plant extracts triggered different stress response pathways from the commercial anthelmintic drugs. This study showed that using traditional knowledge of plant medicinal properties in combination with a C. elegans in vitro screen provided a rapid and economical test with a high hit rate compared with the random screening of plants for nematocidal activities. The use of transgenic C. elegans strains may allow this approach to be refined further to investigate the mode of action of active extracts.


Subject(s)
Anthelmintics/pharmacology , Caenorhabditis elegans/drug effects , Drug Evaluation, Preclinical/methods , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Animals , Anthelmintics/isolation & purification , Genes, Reporter , Green Fluorescent Proteins/analysis , Green Fluorescent Proteins/genetics , Larva/drug effects , Plant Extracts/isolation & purification , Tracheophyta/chemistry
13.
Geobiology ; 12(3): 250-64, 2014 May.
Article in English | MEDLINE | ID: mdl-24636451

ABSTRACT

Pavilion Lake in British Columbia, Canada, is home to modern-day microbialites that are actively growing at multiple depths within the lake. While microbialite morphology changes with depth and previous isotopic investigations suggested a biological role in the formation of these carbonate structures, little is known about their microbial communities. Microbialite samples acquired through the Pavilion Lake Research Project (PLRP) were first investigated for phototrophic populations using Cyanobacteria-specific primers and 16S rRNA gene cloning. These data were expounded on by high-throughput tagged sequencing analyses of the general bacteria population. These molecular analyses show that the microbial communities of Pavilion Lake microbialites are diverse compared to non-lithifying microbial mats also found in the lake. Phototrophs and heterotrophs were detected, including species from the recently described Chloroacidobacteria genus, a photoheterotroph that has not been previously observed in microbialite systems. Phototrophs were shown as the most influential contributors to community differences above and below 25 meters, and corresponding shifts in heterotrophic populations were observed at this interface as well. The isotopic composition of carbonate also mirrored this shift in community states. Comparisons to previous studies indicated this population shift may be a consequence of changes in lake chemistry at this depth. Microbial community composition did not correlate with changing microbialite morphology with depth, suggesting something other than community changes may be a key to observed variations in microbialite structure.


Subject(s)
Archaea/physiology , Bacterial Physiological Phenomena , Biota , Geologic Sediments/microbiology , Lakes/microbiology , Archaea/classification , Archaea/genetics , Archaea/isolation & purification , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , British Columbia , Carbonates/metabolism , DNA Barcoding, Taxonomic , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Sequence Analysis, RNA
14.
J Interv Cardiol ; 27(2): 204-11, 2014 Apr.
Article in English | MEDLINE | ID: mdl-18248358

ABSTRACT

AIM: The intent of the present study was to evaluate changes in ventricular function with percutaneous closure of atrial septal defect (ASD), as it is associated with alterations in ventricular loading and function. Transcatheter occlusion of ASD imparts acute changes in volume loading of the left ventricle (LV) that obscures measurement of ventricular function by load-dependent indices. To differentiate between changes in ventricular loading and function, load-independent indices of ventricular function must be utilized. METHODS: During transcatheter occlusion of ASD, subjects underwent measurement of LV pressure and volume by the conductance catheter method. Load-dependent indices of ventricular function included: systolic and diastolic pressures, +dP/dtmax , and -dP/dtmax . Load-independent indices included: elastance and tau, the preload-independent time constant ofisovolumic relaxation. To obtain elastance, afterload was augmented by phenylephrine bolus pre- and post-device occlusion. RESULTS: In total, 29 patients (age 2-79 years) underwent ASD device occlusion (device size 12-38 mm, median 28 mm). Load-dependent indices were obtained in all, and satisfactory pressure-volume loops in 11. At baseline, LV end-diastolic pressure was 5-23 mmHg (13 ± 5 mmHg) and tau was 31 ± 6 ms. Postclosure of the ASD, LV systolic and diastolic pressures rose by 10 ± 11 mmHg and 5 ± 3 mmHg, respectively (P < 0.05), and +dP/dtmax rose from 1,288 ± 313 mmHg/sec to 1,415 ± 465 mmHg/sec (P < 0.05), but -dP/dtmax was unchanged. Elastance significantly improved (9.4 ± 8.3 mmHg/mL vs. 13.0 ± 7.3 mmHg/mL, P < 0.05) and tau was unchanged. CONCLUSIONS: Transcatheter occlusion of ASD is associated with acute improvement in load-independent indices of systolic function in this cohort, without significant worsening of the preload-independent index of diastolic function.


Subject(s)
Heart Septal Defects, Atrial/physiopathology , Heart Septal Defects, Atrial/surgery , Ventricular Function, Left/physiology , Adolescent , Adult , Aged , Child , Child, Preschool , Humans , Middle Aged
15.
Geobiology ; 11(5): 437-56, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23941467

ABSTRACT

Photosynthetic activity in carbonate-rich benthic microbial mats located in saline, alkaline lakes on the Cariboo Plateau, B.C. resulted in pCO2 below equilibrium and δ(13) CDIC values up to +6.0‰ above predicted carbon dioxide (CO2 ) equilibrium values, representing a biosignature of photosynthesis. Mat-associated δ(13) Ccarb values ranged from ~4 to 8‰ within any individual lake, with observations of both enrichments (up to 3.8‰) and depletions (up to 11.6‰) relative to the concurrent dissolved inorganic carbon (DIC). Seasonal and annual variations in δ(13) C values reflected the balance between photosynthetic (13) C-enrichment and heterotrophic inputs of (13) C-depleted DIC. Mat microelectrode profiles identified oxic zones where δ(13) Ccarb was within 0.2‰ of surface DIC overlying anoxic zones associated with sulphate reduction where δ(13) Ccarb was depleted by up to 5‰ relative to surface DIC reflecting inputs of (13) C-depleted DIC. δ(13) C values of sulphate reducing bacteria biomarker phospholipid fatty acids (PLFA) were depleted relative to the bulk organic matter by ~4‰, consistent with heterotrophic synthesis, while the majority of PLFA had larger offsets consistent with autotrophy. Mean δ(13) Corg values ranged from -18.7 ± 0.1 to -25.3 ± 1.0‰ with mean Δ(13) Cinorg-org values ranging from 21.1 to 24.2‰, consistent with non-CO2 -limited photosynthesis, suggesting that Precambrian δ(13) Corg values of ~-26‰ do not necessitate higher atmospheric CO2 concentrations. Rather, it is likely that the high DIC and carbonate content of these systems provide a non-limiting carbon source allowing for expression of large photosynthetic offsets, in contrast to the smaller offsets observed in saline, organic-rich and hot spring microbial mats.


Subject(s)
Biofilms , Carbonates/metabolism , Cyanobacteria/physiology , Lakes/chemistry , Lakes/microbiology , Biomarkers/metabolism , British Columbia , Carbon Isotopes/metabolism , Fatty Acids/metabolism , Gas Chromatography-Mass Spectrometry , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Phospholipids/metabolism , Salinity , Seasons
16.
Oncogenesis ; 2: e55, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-23857250

ABSTRACT

The transcription coactivator Yes-associated protein 1 (YAP1) is regulated by the Hippo tumor suppressor pathway. However, the role of YAP1 in thyroid cancer, which is frequently associated with the BRAF(V600E) mutation, remains unknown. This study aimed to investigate the role of YAP1 in thyroid cancer. YAP1 was overexpressed in papillary (PTC) and anaplastic thyroid cancer, and nuclear YAP1 was more frequently detected in BRAF(V600E) (+) PTC. In the thyroid cancer cell lines TPC-1 and HTH7, which do not have the BRAF(V600E) mutation, YAP1 was cytosolic and inactive at high cell densities. In contrast, YAP1 was retained in the nucleus and its target genes were expressed in the thyroid cancer cells 8505C and K1, which harbor the BRAF(V600E) mutation, regardless of cell density. Furthermore, the nuclear activation of YAP1 in 8505C was not inhibited by RAF or MEK inhibitor. In vitro experiments, YAP1 silencing or overexpression affected migratory capacities of 8505C and TPC-1 cells. YAP1 knockdown resulted in marked decrease of tumor volume, invasion and distant metastasis in orthotopic tumor xenograft mouse models using the 8505C thyroid cancer cell line. Taken together, YAP1 is involved in the tumor progression of thyroid cancer and YAP1-mediated effects might not be affected by the currently used RAF kinase inhibitors.

17.
J Nanosci Nanotechnol ; 12(7): 5875-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22966673

ABSTRACT

Carbon nanotubes (CNTs) have unique atomic structure and properties, such as a high aspect ratio and high mechanical, electrical and thermal properties. On the other hand, the agglomeration and entanglement of CNTs restrict their applications. Sea urchin-like multiwalled carbon nanotubes, which have a small aspect ratio, can minimize the problem of dispersion. The high hardness, thermal conductivity and chemical inertness of the nano-diamond powder make it suitable for a wide range of applications in the mechanical and electronic fields. CNTs were synthesized on nano-diamond powder by thermal CVD to fabricate a filler with suitable mechanical properties and chemical stability. This paper reports the growth of CNTs with a sea urchin-like structure on the surface of the nano-diamond powder. Nano-diamond powders were dispersed in an attritional milling system using zirconia beads in ethanol. After the milling process, 3-aminopropyltrimethoxysilane (APS) was added as a linker. Silanization was performed between the nano-diamond particles and the metal catalyst. Iron chloride was used as a catalyst for the fabrication of the CNTs. After drying, catalyst-attached nano-diamond powders could be achieved. The growth of the carbon nanotubes was carried out by CVD. The CNT morphology was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The mean diameter and length of the CNTs were 201 nm and 3.25 microm, respectively.

18.
J Nanosci Nanotechnol ; 11(1): 344-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21446453

ABSTRACT

Surface roughness-controlled nanocrystalline diamond film was fabricated as an undulated line and space pattern on a silicon oxide surface. To simulate a MEMS (Micro-/Electro-Mechanical System) and NEMS (Nano-/Electro-Mechanical System) patterned surface, 800 nm and 1 microm wide lines with a 200 nm wide space pattern were prepared on the substrate using E-beam lithography and an ESAND (Electrostatic Self-assembly of NanoDiamond) seeding layer lift-off process. Through this process, an undulated pattern of a nanocrystalline CVD diamond successfully formed by a conventional micro crystalline diamond growth system. The roughness of the deposited surface was controlled by regulating the size of the seeding nanodiamond particles. Crushing of the nanodiamond aggregates and dispersion of the nanodiamond solution was performed in an attrition milling system. An AFM (Atomic Force Microscopy) probe was used for the wear test and surface profiling of nanocrystalline diamond coatings. 2-D friction coefficient mapping by LFM (Lateral Force Microscopy) scanning showed a low friction coefficient (< 0.1) on the line-patterned diamond surface, and a higher friction coefficient (< 0.3) on a narrow area adjacent to the undulated pattern edges. With prolonged LFM scanning, the high coefficient of friction was reduced to less than 0.1. The bonding status of the nanocrystalline diamond was analyzed with Raman spectroscopy.

19.
Oncogene ; 30(2): 201-11, 2011 Jan 13.
Article in English | MEDLINE | ID: mdl-20802527

ABSTRACT

Pancreatic adenocarcinoma upregulated factor (PAUF) is overproduced in certain types of cancer. However, little is known of the tumorigenic function of PAUF. In this study, we report the X-ray crystal structure of PAUF and reveal that PAUF is a mammalian lectin normally found in plant lectins. We also identify PAUF as an endogenous ligand of Toll-like receptor 2 (TLR2) and TLR4 by screening extracellular domain receptor pools. We further confirmed the specificity of the PAUF-TLR2 interaction. PAUF induces extracellular signal-regulated kinase (ERK) phosphorylation and activates the IKK-ß-mediated TPL2/MEK/ERK signaling pathway through TLR2. In agreement with the result of TLR2-mediated ERK activation by PAUF, PAUF induces increased expression of the protumorigenic cytokines RANTES and MIF in THP-1 cells. However, PAUF does not fully activate Iκ-B-α signaling pathways in THP-1 cells, and fails to translocate the p65 subunit of the nuclear factor-κB (NF-κB) complex into the nucleus, resulting in no NF-κB activation. Surprisingly, we found that PAUF also associated with the CXC chemokine receptor (CXCR4)-TLR2 complex and inhibited CXCR4-dependent, TLR2-mediated NF-κB activation. Together, these findings suggest that the new cancer-associated ligand, PAUF, may activate TLR-mediated ERK signaling to produce the protumorigenic cytokines, but inhibits TLR-mediated NF-κB signaling, thereby facilitating tumor growth and escape from innate immune surveillance.


Subject(s)
Adenocarcinoma/secondary , Lectins/metabolism , Pancreatic Neoplasms/pathology , Receptors, CXCR4/metabolism , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Animals , CHO Cells , Chemokine CCL5/analysis , Chemokine CCL5/metabolism , Cricetinae , Cricetulus , Crystallography , Extracellular Signal-Regulated MAP Kinases/analysis , Extracellular Signal-Regulated MAP Kinases/metabolism , HEK293 Cells , Humans , I-kappa B Kinase/analysis , I-kappa B Kinase/metabolism , Intercellular Signaling Peptides and Proteins , Intramolecular Oxidoreductases/analysis , Intramolecular Oxidoreductases/metabolism , Lectins/chemistry , MAP Kinase Kinase Kinases/analysis , MAP Kinase Kinase Kinases/metabolism , Macrophage Migration-Inhibitory Factors/analysis , Macrophage Migration-Inhibitory Factors/metabolism , Pancreatic Neoplasms/metabolism , Phosphorylation , Protein Binding , Protein Structure, Tertiary , Proto-Oncogene Proteins/analysis , Proto-Oncogene Proteins/metabolism , Substrate Specificity , Up-Regulation
20.
Oncogene ; 29(1): 56-67, 2010 Jan 07.
Article in English | MEDLINE | ID: mdl-19784070

ABSTRACT

Pancreatic cancer is characterized by early metastatic spread, but the process of tumor cell dissemination is largely unknown. In this study we show that the soluble protein pancreatic adenocarcinoma upregulated factor (PAUF) has an important role in the metastasis and progression of the disease. Variations in the level of PAUF, either by overexpression or knockdown, resulted in altered migration, invasion and proliferation capacity of pancreatic cancer cells. Moreover, depletion of PAUF in metastatic cells dramatically abrogated the spread of the cells to distant organs in an orthotopic xenograft mouse model. PAUF elicited the activation of the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and AKT intracellular signaling cascades and consequently their downstream transcription factors in an autocrine manner. Genome-wide expression analysis revealed that C-X-C chemokine receptor type 4 (CXCR4) expression was induced by PAUF overexpression but was repressed by PAUF knockdown. The PAUF-mediated increase in cancer cell motility was attenuated by the CXCR4 inhibitor, AMD3100, or by anti-CXCR4 antibody. Furthermore, immunohistochemical analysis of pancreatic tumor tissues clearly showed a significant positive correlation between PAUF and CXCR4 expression. Collectively, these findings indicate that PAUF enhances the metastatic potential of pancreatic cancer cells, at least in part, by upregulating CXCR4 expression.


Subject(s)
Lectins/genetics , Pancreatic Neoplasms/pathology , Receptors, CXCR4/genetics , Up-Regulation , Animals , Benzylamines , Blotting, Western , Cell Line, Tumor , Cell Movement/drug effects , Cyclams , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Heterocyclic Compounds/pharmacology , Humans , Immunohistochemistry , Intercellular Signaling Peptides and Proteins , Lectins/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Oligonucleotide Array Sequence Analysis , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , RNA Interference , Receptors, CXCR4/antagonists & inhibitors , Receptors, CXCR4/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Transplantation, Heterologous
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