PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (164)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
more »
1.  Humoral Immunity to AAV-6, 8, and 9 in Normal and Dystrophic Dogs 
Human Gene Therapy  2011;23(3):287-294.
Abstract
Adeno-associated virus (AAV)-6, 8, and 9 are promising gene-delivery vectors for testing novel Duchenne muscular dystrophy gene therapy in the canine model. Humoral immunity greatly influences in vivo AAV transduction. However, neutralizing antibodies to AAV-6, 8, and 9 have not been systemically examined in normal and dystrophic dogs. To gain information on the seroprevalence of antibodies to AAV-6, 8, and 9, we measured neutralizing antibody titers using an in vitro transduction inhibition assay. We examined 72 naive serum samples and 26 serum samples obtained from dogs that had received AAV gene transfer. Our data demonstrated that AAV-6 neutralizing antibody was the most prevalent antibody in dogs irrespective of age, gender, disease status (dystrophic or not), and prior parvovirus vaccination history. Surprisingly, high-level anti-AAV-6 antibody was detected at birth in newborn puppies. Further, a robust antibody response was induced in affected, but not normal newborn dogs following systemic AAV gene transfer. Taken together, our data have provided an important baseline on the seroprevalence of AAV-6, 8, and 9 neutralizing antibodies in normal and Duchenne muscular dystrophy dogs. These results will help guide translational AAV gene-therapy studies in dog models of muscular dystrophy.
Shin and colleagues have conducted a large-scale survey on seroprevalence of AAV-6, -8, and -9 neutralizing antibodies in normal, carrier, and dystrophin-deficient dogs. Their data demonstrate that AAV-6 neutralizing antibody is the most prevalent antibody in dogs irrespective of age, sex, disease status (dystrophic or not), and prior parvovirus vaccination history. High-level anti-AAV-6 antibody is detected as early as birth in newborn puppies. The authors also show that a robust antibody response is induced in affected, but not normal, newborn dogs after systemic AAV gene transfer.
doi:10.1089/hum.2011.125
PMCID: PMC3300072  PMID: 22040468
2.  Bioavailability of nanoemulsified conjugated linoleic acid for an antiobesity effect 
Background:
The aim of this study was to enhance the bioavailability of conjugated linoleic acid (CLA), which has low water solubility, using nanoemulsion technology and to evaluate the effects of its improved bioavailability as an antiobesity agent.
Methods:
The antiobesity effect of nanoemulsified water-soluble conjugated linoleic acid (N-CLA) was evaluated using in vitro and in vivo studies. Differentiated 3T3-L1 adipocytes were treated with CLA and N-CLA to assess their lipolytic effect. Further, to confirm the antiobesity effect of N-CLA, male Sprague-Dawley rats were randomly separated into four groups, ie, a group fed a normal diet, a group fed a high-fat diet (obesity rat model), a CLA-treated group, and an N-CLA-treated group.
Results:
N-CLA showed a greater lipolytic effect on differentiated 3T3-L1 adipocytes compared with normal CLA. N-CLA enhanced the release of glycerol from triglycerides, which accumulated in differentiated 3T3-L1 adipocytes. Further, N-CLA enhanced leptin secretion to an extent similar to that of orlistat, an antiobesity agent. In an animal obesity model fed a high-fat diet, N-CLA attenuated accumulation of triglycerides, total cholesterol, and low-density lipoprotein cholesterol in serum, and also significantly decreased the volume of triglycerides and cholesterol in liver tissue.
Conclusion:
These results indicate that N-CLA has a greater antiobesity effect than CLA as a result of its improved bioavailability.
doi:10.2147/IJN.S38430
PMCID: PMC3575163  PMID: 23429301
conjugated linoleic acid; nanoemulsion; water-soluble; improved bioavailability; antiobesity
3.  A Simplified Immune Suppression Scheme Leads to Persistent Micro-dystrophin Expression in Duchenne Muscular Dystrophy Dogs 
Human Gene Therapy  2011;23(2):202-209.
Abstract
Highly abbreviated micro-dystrophin genes have been intensively studied for Duchenne muscular dystrophy (DMD) gene therapy. Following adeno-associated virus (AAV) gene transfer, robust microgene expression is achieved in murine DMD models in the absence of immune suppression. Interestingly, a recent study suggests that AAV gene transfer in dystrophic dogs may require up to 18 weeks' immune suppression using a combination of three different immune-suppressive drugs (cyclosporine, mycophenolate mofetil, and anti-dog thymocyte globulin). Continued immune suppression is not only costly but also may cause untoward reactions. Further, some of the drugs (such as anti-dog thymocyte globulin) are not readily available. To overcome these limitations, we developed a novel 5-week immune suppression scheme using only cyclosporine and mycophenolate mofetil. AAV vectors (either AV.RSV.AP that expresses the heat-resistant human alkaline phosphatase gene, or AV.CMV.μDys that expresses the canine R16-17/H3/ΔC microgene) at 2.85×1012 vg particles were injected into adult dystrophic dog limb muscles under the new immune suppression protocol. Sustained transduction was observed for nearly half year (the end of the study). The simplified immune suppression strategy described here may facilitate preclinical studies in the dog model.
Shin and colleagues develop and test a novel immune suppression scheme to allow for successful recombinant adeno-associated virus (AAV)-mediated microdystrophin gene transfer to dystrophic dogs. This shorter, simplified scheme uses readily available drugs such as cyclosporine and mycophenolate, administered over the course of 5 weeks. Adult dystrophic dog limb muscles injected with AAV encoding a canine dystrophin microgene under the new immune suppression protocol show sustained transduction for nearly half a year.
doi:10.1089/hum.2011.147
PMCID: PMC3277733  PMID: 21967249
4.  Interstitial Lung Disease in a Patient with Dyskeratosis Congenita 
Dyskeratosis congenita is a rare congenital disorder characterized by a triad of reticular pigmentation of the skin, dystrophic nails, and leukoplakia of the mucous membrane. Sometimes it is associated with bone marrow failure, secondary malignancy and interstitial lung disease. Though it is rare, Dyskeratosis congenita is diagnosed relatively easily when clinicians suspect it. It can be diagnosed just by gross inspection with care. Dyskeratosis congenita should be considered as one cause associated with interstitial lung disease. In Korea, interstitial lung disease with dyskeratosis congenita has not been reported. We report a case and review the literature.
doi:10.4046/trd.2013.74.2.70
PMCID: PMC3591541  PMID: 23483786
Lung Diseases, Interstitial; Dyskeratosis Congenita; Anemia, Aplastic
5.  Endoscopic large-balloon dilation alone versus endoscopic sphincterotomy plus large-balloon dilation for the treatment of large bile duct stones 
BMC Gastroenterology  2013;13:15.
Background
Endoscopic sphincterotomy (EST) combined with large-balloon dilation (LBD) has been proposed as an alternative to manage large bile duct stones. However, recent reports indicate that LBD without EST may be safe and effective in this setting.
Methods
One hundred thirty-one patients with large common bile duct (CBD) stones 12 mm in size or larger underwent LBD alone (n = 62) or EST plus LBD (n = 69) for lithotripsy. The therapeutic outcome and complications were reviewed and compared.
Results
There were no differences between the two groups with regard to age, size and number of stones, or bile duct diameter. The LBD alone group (mean age, 70.4 years) and the EST plus LBD group (mean age, 68.2 years) had similar outcomes in terms of overall successful stone removal (96.8% vs. 95.7%, P = 0.738) and complete stone removal without the need for mechanical lithotripsy (80.6% vs. 73.9%, P = 0.360). Complications in the LBD alone and EST plus LBD groups were as follows: pancreatitis (6.5% vs. 4.3%, P = 0.593), impaction of basket and stone (0% vs. 1.4%, P = 0.341), and perforation (0% vs. 1.4%, P = 0.341).
Conclusions
LBD alone may be a simple, safe, and effective alternative to EST plus LBD in relatively aged patients with large CBD stones, and it can simplify the procedure compared with EST plus LBD.
doi:10.1186/1471-230X-13-15
PMCID: PMC3556067  PMID: 23324454
Common bile duct stones; Endoscopic sphincterotomy; Large-balloon dilation
6.  Genome-Wide Screens for In Vivo Tinman Binding Sites Identify Cardiac Enhancers with Diverse Functional Architectures 
PLoS Genetics  2013;9(1):e1003195.
The NK homeodomain factor Tinman is a crucial regulator of early mesoderm patterning and, together with the GATA factor Pannier and the Dorsocross T-box factors, serves as one of the key cardiogenic factors during specification and differentiation of heart cells. Although the basic framework of regulatory interactions driving heart development has been worked out, only about a dozen genes involved in heart development have been designated as direct Tinman target genes to date, and detailed information about the functional architectures of their cardiac enhancers is lacking. We have used immunoprecipitation of chromatin (ChIP) from embryos at two different stages of early cardiogenesis to obtain a global overview of the sequences bound by Tinman in vivo and their linked genes. Our data from the analysis of ∼50 sequences with high Tinman occupancy show that the majority of such sequences act as enhancers in various mesodermal tissues in which Tinman is active. All of the dorsal mesodermal and cardiac enhancers, but not some of the others, require tinman function. The cardiac enhancers feature diverse arrangements of binding motifs for Tinman, Pannier, and Dorsocross. By employing these cardiac and non-cardiac enhancers in machine learning approaches, we identify a novel motif, termed CEE, as a classifier for cardiac enhancers. In vivo assays for the requirement of the binding motifs of Tinman, Pannier, and Dorsocross, as well as the CEE motifs in a set of cardiac enhancers, show that the Tinman sites are essential in all but one of the tested enhancers; although on occasion they can be functionally redundant with Dorsocross sites. The enhancers differ widely with respect to their requirement for Pannier, Dorsocross, and CEE sites, which we ascribe to their different position in the regulatory circuitry, their distinct temporal and spatial activities during cardiogenesis, and functional redundancies among different factor binding sites.
Author Summary
The Drosophila homeodomain protein Tinman was the first transcription factor found to control the development and differentiation of the heart in any species. In spite of that, our knowledge of the number, identities, and mode of regulation of the downstream target genes of Tinman that are necessary to exert its cardiogenic functions is still very incomplete. To address these issues, we have performed a genome-wide analysis of DNA regions associated with Tinman-binding in embryos and the genes linked to them. The combined data from our in-depth in vivo assays of sequence elements with high Tinman occupancy allow the following general conclusions: (1) The majority of such sequences are active as regulatory elements (called enhancers) in mesodermal tissues that include Tinman-expressing cells. (2) The enhancers active in the heart progenitor cells and the heart generally are dependent on tinman gene activity, whereas those active in non-cardiac mesoderm are often bound neutrally by Tinman. (3) Tinman binding motifs in most cases are essential for cardiac enhancer activity, but in some cases they can be functionally-redundant with those of other cardiogenic factors. (4) Tinman-occupied cardiac enhancers are enriched for a newly discovered binding motif for an unknown factor that is functional in vivo.
doi:10.1371/journal.pgen.1003195
PMCID: PMC3542182  PMID: 23326246
7.  Circulating microRNAs as Specific Biomarkers for Breast Cancer Detection 
PLoS ONE  2013;8(1):e53141.
Background
We previously showed microRNAs (miRNAs) in plasma are potential biomarkers for colorectal cancer detection. Here, we aimed to develop specific blood-based miRNA assay for breast cancer detection.
Methodology/Principal Findings
TaqMan-based miRNA profiling was performed in tumor, adjacent non-tumor, corresponding plasma from breast cancer patients, and plasma from matched healthy controls. All putative markers identified were verified in a training set of breast cancer patients. Selected markers were validated in a case-control cohort of 170 breast cancer patients, 100 controls, and 95 other types of cancers and then blindly validated in an independent set of 70 breast cancer patients and 50 healthy controls. Profiling results showed 8 miRNAs were concordantly up-regulated and 1 miRNA was concordantly down-regulated in both plasma and tumor tissue of breast cancer patients. Of the 8 up-regulated miRNAs, only 3 were significantly elevated (p<0.0001) before surgery and reduced after surgery in the training set. Results from the validation cohort showed that a combination of miR-145 and miR-451 was the best biomarker (p<0.0001) in discriminating breast cancer from healthy controls and all other types of cancers. In the blind validation, these plasma markers yielded Receiver Operating Characteristic (ROC) curve area of 0.931. The positive predictive value was 88% and the negative predictive value was 92%. Altered levels of these miRNAs in plasma have been detected not only in advanced stages but also early stages of tumors. The positive predictive value for ductal carcinoma in situ (DCIS) cases was 96%.
Conclusions
These results suggested that these circulating miRNAs could be a potential specific biomarker for breast cancer screening.
doi:10.1371/journal.pone.0053141
PMCID: PMC3536802  PMID: 23301032
8.  Recombinant Adeno-Associated Viral Vector Production and Purification 
Gene delivery vectors based on recombinant adeno-associated virus (AAV) are powerful tools for studying myogenesis in normal and diseased conditions. Strategies have been developed to use AAV to increase, down-regulate, or modify expression of a particular muscle gene in a specific muscle, muscle group(s), or all muscles in the body. AAV-based muscle gene therapy has been shown to cure several inherited muscle diseases in animal models. Early clinical trials have also yielded promising results. In general, AAV vectors lead to robust, long-term in vivo transduction in rodents, dogs, and non-human primates. To meet specific research needs, investigators have developed numerous AAV variants by engineering viral capsid and/or genome. Here we outline a generic AAV production and purification protocol. Techniques described here are applicable to any AAV variant.
doi:10.1007/978-1-61779-343-1_15
PMCID: PMC3298690  PMID: 22130842
AAV; Adeno-associated virus; Muscle; Gene therapy; Gene transfer/delivery; Serotype; Muscular dystrophy; Dystrophin; Alkaline phosphatase
9.  Semaphorin 7a Links Nerve Regeneration and Inflammation in the Cornea 
Purpose.
We determined Semaphorin 7a (Sema7a) localization and abundance in naive corneas and in corneas after nerve-transecting lamellar flap surgery, and determined the effect of Sema7a supplementation on corneal nerve regeneration and inflammation.
Methods.
Immunolocalization and Western blot analyses were performed to evaluate the abundance of Sema7a in naive corneas and corneas undergoing nerve regeneration after lamellar corneal surgery in thy1-YFP+ neurofluorescent mice. We used compartmental cultures of dissociated trigeminal ganglion cells to determine the effect of Sema7a exposure on neurite outgrowth in vitro. Finally, a Sema7a pellet was implanted under the corneal flap after lamellar transection surgery to determine the neuronal and inflammatory effects of Sema7a supplementation in vivo.
Results.
Sema7a was expressed in the corneal epithelium and stromal keratocytes, but was more abundant in the epithelium (74.3%) compared to the stroma (25.7%, P = 0.02). Sema7a expression was increased significantly in the cornea after lamellar corneal surgery and was localized to stromal cells near the regenerating nerve fronds. Exposure of trigeminal neurites to Sema7a (20 nM) in the side compartment increased neurite length significantly. The implanted Sema7a pellet increased significantly YFP+ inflammatory cell influx into the cornea as well as increased corneal nerve length.
Conclusions.
Sema7a is expressed constitutively in the cornea, and potently stimulates nerve regeneration and inflammatory cell influx. Therefore, this immune semaphorin links nerve regeneration and inflammatory processes in the cornea.
Semaphorin 7a (Sema7a) potently stimulates corneal nerve regeneration and inflammatory cell influx. This immune semaphorin links nerve regeneration and inflammatory processes in the cornea.
doi:10.1167/iovs.12-9760
PMCID: PMC3394693  PMID: 22700709
10.  Molecular and Cellular Response Profiles Induced by the TLR4 Agonist-Based Adjuvant Glucopyranosyl Lipid A 
PLoS ONE  2012;7(12):e51618.
Background
Toll-like receptor (TLR)4 agonists are known potent immunostimulatory compounds. These compounds can be formulated as part of novel adjuvants to enhance vaccine medicated immune responses. However, the contribution of the formulation to the innate in vivo activity of TLR4 agonist compounds is not well understood.
Methodology and Principal Findings
We evaluated synthetic TLR4 agonist Glucopyranosyl Lipid A (GLA) for its effects on molecular and cellular innate immune responses in the murine model. Microarray techniques were used to compare the responses to GLA in an aqueous formulation or in an oil-in-water Stable Emulsion formulation (GLA-SE) versus either SE alone or the mineral salt aluminum hydroxide (alum) at the muscle injection site over multiple timepoints. In contrast to the minimal gene upregulation induced by SE and alum, both GLA and GLA-SE triggered MyD88- and TRIF-dependent gene expression. Genes for chemokines, cytokine receptors, signaling molecules, complement, and antigen presentation were also strongly upregulated by GLA and GLA-SE. These included chemokines for TH1-type T cells (CXCL9 and CXCL10) and mononuclear leukocytes (CCL2, CCL3) among others. GLA-SE induced stronger and more sustained gene upregulation than GLA in the muscle; GLA-SE induced genes were also detected in local draining lymph nodes and at lower levels in peripheral blood. Both GLA and GLA-SE resulted in increased cellular trafficking to the draining lymph nodes and upregulated MHC molecules and ICAM1 on local dendritic cells. GLA and GLA-SE transiently upregulated circulating MCP-1, TNFα, IFNγ and IP-10 in blood.
Conclusions/Significance
While GLA and GLA-SE activate a large number of shared innate genes and proteins, GLA-SE induces a quantitatively and qualitatively stronger response than GLA, SE or alum. The genes and proteins upregulated could be used to facilitate selection of appropriate adjuvant doses in vaccine formulations.
doi:10.1371/journal.pone.0051618
PMCID: PMC3532059  PMID: 23284726
11.  Two New Species of Cryptococcus sp. and Candida sp. from Wild Flowers in Korea 
Mycobiology  2012;40(4):255-257.
Among 80 types of yeast isolated from wild flowers in Daejeon, Korea, two species that have not yet been identified by phylogenetic analysis of the internal transcribed spacer-2 (ITS2) genes and 26S rDNA sequences were identified as Candida sp. 44-C-1 and Cryptococcus sp. 9-D-1. Neither of the newly identified species formed ascospores, while Candida sp. 44-C-1 formed pseudomycelium and Cryptococcus sp. 9-D-1 did not.
doi:10.5941/MYCO.2012.40.4.255
PMCID: PMC3538973  PMID: 23323051
26S rDNA sequence; Candida sp. 44-C-1; Cryptococcus sp. 9-D-1; Internal transcribed spacer 2; Phylogenetic analysis
12.  Postoperative radiotherapy for ependymoma 
Radiation Oncology Journal  2012;30(4):158-164.
Purpose
To evaluated the patterns of failure, survival rate, treatment-related toxicity and prognostic factors in postoperative radiotherapy of patients with ependymoma.
Materials and Methods
Thirty patients who underwent surgery and postoperative radiotherapy for ependymoma between the period of June 1994 and June 2008 were reviewed retrospectively. The age of patients ranged from 21 months to 66 years (median, 19 years). Seventeen patients had grade II ependymoma, and 13 had grade III anaplastic ependymoma according to the World Health Organization grading system. The postoperative irradiation was performed with 4 or 6 MV photon beam with median dose of 52.8 Gy (range, 45 to 63 Gy), and radiation field including 2 cm beyond the preoperative tumor volume. Median follow-up period was 51 months (range, 12 to 172 months).
Results
Fourteen out of 30 (46.7%) patients experienced recurrence, and 12 of those died. Among those 14 patients who experienced recurrence, 11 were in-field and 3 were out-of-field recurrence. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 66.7% and 56.1%, respectively. On univariate analysis, tumor grade was a statistically significant prognostic factor for OS and PFS. There were two complications after surgery and postoperative radiotherapy, including short stature and facial palsy on the left side.
Conclusion
We observed good survival rates, and histologic grade was a prognostic factor affecting the OS and PFS. Almost all recurrence occurred in primary tumor site, thus we suggest further evaluation on intensity-modulated radiotherapy or stereotatic radiosurgery for high-risk patients such as who have anaplastic ependymoma.
doi:10.3857/roj.2012.30.4.158
PMCID: PMC3546283  PMID: 23346534
Ependymoma; Anaplastic ependymoma; Radiotherapy; Histologic grade; Stereotatic radiosurgery
13.  Prognostic value of 18F-fluorodeoxyglucose positron emission tomography, computed tomography and magnetic resonance imaging in oral cavity squamous cell carcinoma with pathologically positive neck lymph node 
Radiation Oncology Journal  2012;30(4):173-181.
Purpose
To evaluate the prognostic value of preoperative neck lymph node (LN) assessment with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), computed tomography (CT), and magnetic resonance imaging (MRI) in oral cavity squamous cell carcinoma (OSCC) patients with pathologically positive LN.
Materials and Methods
In total, 47 OSCC patients with pathologically positive LN were retrospectively reviewed with preoperative 18F-FDG PET and CT/MRI. All patients underwent surgical resection, neck dissection and postoperative adjuvant radiotherapy and/or chemotherapy between March 2002 and October 2010. Histologic correlation was performed for findings of 18F-FDG PET and CT/MRI.
Results
Thirty-six (76.6%) of 47 cases were correctly diagnosed with neck LN metastasis by 18F-FDG PET and 32 (68.1%) of 47 cases were correctly diagnosed by CT/MRI. Follow-up ranged from 20 to 114 months (median, 56 months). Clinically negative nodal status evaluated by 18F-FDG PET or CT/MRI revealed a trend toward better clinical outcomes in terms of overall survival, disease-free survival, local recurrence-free survival, regional nodal recurrence-free survival, and distant metastasis-free survival rates even though the trends were not statistically significant. However, there was no impact of neck node standardized uptake value (SUVmax) on clinical outcomes. Notably, SUVmax showed significant correlation with tumor size in LN (p < 0.01, R2 = 0.62). PET and CT/MRI status of LN also had significant correlation with the size of intranodal tumor deposit (p < 0.05, R2 = 0.37 and p < 0.01, R2 = 0.48, respectively).
Conclusion
18F-FDG PET and CT/MRI at the neck LNs might improve risk stratification in OSCC patients with pathologically positive neck LN in this study, even without significant prognostic value of SUVmax.
doi:10.3857/roj.2012.30.4.173
PMCID: PMC3546285  PMID: 23346536
Oral cavity squamous cell carcinoma; Neck lymph node; Magnetic resonance imaging; X-ray computed tomography; 18F-FDG PET; Prognostic value
14.  Cox-Maze III procedure with valvular surgery in an autopneumonectomized patient 
Destructive pulmonary inflammation can leave patients with only a single functional lung, resulting in anatomical and physiological changes that may interfere with subsequent cardiac surgeries. Such patients are vulnerable to perioperative cardiopulmonary complications. Herein, we report the first case, to our knowledge, of an autopneumonectomized patient who successfully underwent a modified Cox-Maze III procedure combined with valvular repairs. The three major findings in this case can be summarized as follows: (1) a median sternotomy with peripheral cannulations, such as femoral cannulations, can provide an optimal exposure and prevent the obstruction of vision that may occur as a result of multiple cannulations through a median sternotomy; (2) a modified septal incision combined with biatrial incisions facilitate adequate exposure of the mitral valve; and (3) the aggressive use of intraoperative ultrafiltration may be helpful for the perioperative managements as decreasing pulmonary water contents, thereby avoiding the pulmonary edema associated with secretion of inflammatory cytokines during a cardiopulmonary bypass. We also provide several suggestions for achieving similar satisfactory surgical outcomes in patients with a comparable condition.
doi:10.1186/1749-8090-7-116
PMCID: PMC3508941  PMID: 23137038
Arrhythmia therapy; Mitral valve repair; Pneumonectomy
15.  Preclinical Study of Treatment Response in HCT-116 Cells and Xenografts with 1H-decoupled 31P MRS 
NMR in biomedicine  2011;24(9):1159-1168.
The topoisomerase I inhibitor, irinotecan, and its active metabolite SN-38 have been shown to induce G2/M cell cycle arrest without significant cell death in human colon carcinoma cells (HCT-116). Subsequent treatment of these G2/M-arrested cells with the cyclin-dependent kinase inhibitor, flavopiridol, induced these cells to undergo apoptosis. The goal of this study was to develop a noninvasive metabolic biomarker for early tumor response and target inhibition of irinotecan followed by flavopiridol treatment in a longitudinal study. A total of eleven mice bearing HCT-116 xenografts were separated into two cohorts where one cohort was administered saline and the other treated with a sequential course of irinotecan followed by flavopiridol. Each mouse xenograft was longitudinally monitored with proton (1H)-decoupled phosphorus (31P) magnetic resonance spectroscopy (MRS) before and after treatment. A statistically significant decrease in phosphocholine (p = 0.0004) and inorganic phosphate (p = 0.0103) levels were observed in HCT-116 xenografts following treatment, which were evidenced within twenty-four hours of treatment completion. Also, a significant growth delay was found in treated xenografts. To discern the underlying mechanism for the treatment response of the xenografts, in vitro HCT-116 cell cultures were investigated with enzymatic assays, cell cycle analysis, and apoptotic assays. Flavopiridol had a direct effect on choline kinase as measured by a 67% reduction in the phosphorylation of choline to phosphocholine. Cells treated with SN-38 alone underwent 83±5% G2/M cell cycle arrest compared to untreated cells. In cells, flavopiridol alone induced 5±1% apoptosis while the sequential treatment (SN-38 then flavopiridol) resulted in 39±10% apoptosis. In vivo 1H-decoupled 31P MRS indirectly measures choline kinase activity. The decrease in phosphocholine may be a potential indicator of early tumor response to the sequential treatment of irinotecan followed by flavopiridol in noninvasive and/or longitudinal studies.
doi:10.1002/nbm.1674
PMCID: PMC3201722  PMID: 21994185
irinotecan; flavopiridol; choline kinase; colon cancer; 1H-decoupled 31P MRS; apoptosis
16.  Insertion of Self Expandable Metal Stent for Malignant Stomal Obstruction in a Patient with Advanced Colon Cancer 
Clinical Endoscopy  2012;45(4):448-450.
Self expandable metal stent can be used both as palliative treatment for malignant colorectal obstruction and as a bridge to surgery in patients with potentially resectable colorectal cancer. Here, we report a case of successful relief of malignant stomal obstruction using a metal stent. A 56-year-old man underwent loop ileostomy and was given palliative chemotherapy for ascending colon cancer with peritoneal carcinomatosis. Eight months after the surgery, he complained of abdominal pain and decreased fecal output. Computed tomography and endoscopy revealed malignant stomal obstruction. Due to his poor clinical condition, we inserted the stent at the stomal orifice, instead of additional surgery, and his obstructive symptoms were successfully relieved. Stent insertion is thought to be a good alternative treatment for malignant stomal obstruction, instead of surgery.
doi:10.5946/ce.2012.45.4.448
PMCID: PMC3521953  PMID: 23251899
Stents; Neoplasms; Stoma
17.  Variation in Estimated Ozone-Related Health Impacts of Climate Change due to Modeling Choices and Assumptions 
Environmental Health Perspectives  2012;120(11):1559-1564.
Background: Future climate change may cause air quality degradation via climate-induced changes in meteorology, atmospheric chemistry, and emissions into the air. Few studies have explicitly modeled the potential relationships between climate change, air quality, and human health, and fewer still have investigated the sensitivity of estimates to the underlying modeling choices.
Objectives: Our goal was to assess the sensitivity of estimated ozone-related human health impacts of climate change to key modeling choices.
Methods: Our analysis included seven modeling systems in which a climate change model is linked to an air quality model, five population projections, and multiple concentration–response functions. Using the U.S. Environmental Protection Agency’s (EPA’s) Environmental Benefits Mapping and Analysis Program (BenMAP), we estimated future ozone (O3)-related health effects in the United States attributable to simulated climate change between the years 2000 and approximately 2050, given each combination of modeling choices. Health effects and concentration–response functions were chosen to match those used in the U.S. EPA’s 2008 Regulatory Impact Analysis of the National Ambient Air Quality Standards for O3.
Results: Different combinations of methodological choices produced a range of estimates of national O3-related mortality from roughly 600 deaths avoided as a result of climate change to 2,500 deaths attributable to climate change (although the large majority produced increases in mortality). The choice of the climate change and the air quality model reflected the greatest source of uncertainty, with the other modeling choices having lesser but still substantial effects.
Conclusions: Our results highlight the need to use an ensemble approach, instead of relying on any one set of modeling choices, to assess the potential risks associated with O3-related human health effects resulting from climate change.
doi:10.1289/ehp.1104271
PMCID: PMC3556604  PMID: 22796531
climate change; mortality; ozone; population projections; sensitivity analysis
18.  MT1-MMP Cleavage of the Anti-angiogenic Proteoglycan Decorin: Role in Corneal Angiogenesis 
Cornea  2011;30(Suppl 1):S45-S49.
Purpose
Decorin is a small chondroitin sulfate proteoglycan that inhibits vascular endothelial cell migration and tube formation. Membrane type 1-matrix metalloproteinase (MT1-MMP) has been shown to be an important angiogenic enzyme in the cornea. We evaluated the specific role of MT1-MMP in decorin cleavage in the cornea.
Methods
Western blotting was used to evaluate decorin degradation by MT1-MMP. Aortic ring tube formation assays were used to assay the inhibitory effect of decorin and the stimulatory effect of MT1-MMP on vascular endothelial cells in vitro. Corneal micropocket assays employing basic fibroblast growth factor (bFGF) were used to assess changes in the levels of decorin and MT1-MMP.
Results
MT1-MMP cleaves decorin in a time- and concentration-dependent manner in vitro. MT1-MMP levels were upregulated following in vivo bFGF pellet implantation in the cornea, and decorin cleavage products were detected in bFGF-implanted corneas but not in normal corneas. MT1-MMP reduced the inhibitory effects of decorin on aortic ring tube formation in vitro.
Conclusion
MT1-MMP may play an essential role in angiogenesis through proteolytic processing of decorin in the cornea.
doi:10.1097/ICO.0b013e31822816e0
PMCID: PMC3181092  PMID: 21912230
angiogenesis; cornea; decorin; MT1-MMP
19.  The evolution of heart gene delivery vectors 
The Journal of Gene Medicine  2011;13(10):557-565.
Gene therapy holds promise for treating numerous heart diseases. A key premise for the success of cardiac gene therapy is the development of powerful gene transfer vehicles that can achieve highly efficient and persistent gene transfer specifically in the heart. Other features of an ideal vector include negligible toxicity, minimal immunogenicity and easy manufacturing. Rapid progress in the fields of molecular biology and virology has offered great opportunities to engineer various genetic materials for heart gene delivery. Several nonviral vectors (e.g. naked plasmids, plasmid lipid/polymer complexes and oligonucleotides) have been tested. Commonly used viral vectors include lentivirus, adenovirus and adeno-associated virus. Among these, adeno-associated virus has shown many attractive features for pre-clinical experimentation in animal models of heart diseases. We review the history and evolution of these vectors for heart gene transfer.
doi:10.1002/jgm.1600
PMCID: PMC3292875  PMID: 21837689
AAV; adenovirus; adeno-associated virus; heart gene delivery; lentivirus; nonviral vector; viral vector
20.  Dystrophin Deficiency Compromises Force Production of the Extensor Carpi Ulnaris Muscle in the Canine Model of Duchenne Muscular Dystrophy 
PLoS ONE  2012;7(9):e44438.
Loss of muscle force is a salient feature of Duchenne muscular dystrophy (DMD), a fatal disease caused by dystrophin deficiency. Assessment of force production from a single intact muscle has been considered as the gold standard for studying physiological consequences in murine models of DMD. Unfortunately, equivalent assays have not been established in dystrophic dogs. To fill the gap, we developed a novel in situ protocol to measure force generated by the extensor carpi ulnaris (ECU) muscle of a dog. We also determined the muscle length to fiber length ratio and the pennation angle of the ECU muscle. Muscle pathology and contractility were compared between normal and affected dogs. Absence of dystrophin resulted in marked histological damage in the ECU muscle of affected dogs. Central nucleation was significantly increased and myofiber size distribution was altered in the dystrophic ECU muscle. Muscle weight and physiological cross sectional area (PCSA) showed a trend of reduction in affected dogs although the difference did not reach statistical significance. Force measurement revealed a significant decrease of absolute force, and the PCSA or muscle weight normalized specific forces. To further characterize the physiological defect in affected dog muscle, we conducted eccentric contraction. Dystrophin-null dogs showed a significantly greater force loss following eccentric contraction damage. To our knowledge, this is the first convincing demonstration of force deficit in a single intact muscle in the canine DMD model. The method described here will be of great value to study physiological outcomes following innovative gene and/or cell therapies.
doi:10.1371/journal.pone.0044438
PMCID: PMC3433412  PMID: 22973449
21.  The Receptor Binding Specificity of the Live Attenuated Influenza H2 and H6 Vaccine Viruses Contributes to Vaccine Immunogenicity and Protection in Ferrets 
Journal of Virology  2012;86(5):2780-2786.
To prepare for influenza pandemics that may be caused by the H2 and H6 subtype influenza viruses, live attenuated influenza virus (LAIV) H2 and H6 vaccines are being developed and evaluated. The H2 and H6 vaccine candidates with different receptor binding preferences specified by amino acid substitutions at residues 226 and 228 were generated and evaluated for their growth in embryonated chicken eggs and their immunogenicity and protection against wild-type virus challenge in the ferret model. The viruses containing Q226 and G228 in the hemagglutinin (HA) protein bound to the avian-like α2,3-sialic acid (SA) receptor and replicated efficiently in chicken eggs. The viruses with L226 and G228 bound preferentially to the human-like α2,6-SA receptor. The viruses containing L226 and S228 displayed dual binding to both α2,3-SA and α2,6-SA receptors and replicated efficiently in eggs. The strains containing L226/G228 or L226/S228 that preferentially bound to α2,6-SA receptors replicated efficiently in the upper respiratory tract of ferrets, induced high levels of neutralizing antibody, and conferred a high level of protection against wild-type virus challenge infection compared to the strain with the Q226/G228 residues. Our data suggest that pandemic vaccines with receptor binding preference to both avian- and human-like receptors might be desired for efficient viral replication in eggs and for inducing protective immune responses in humans.
doi:10.1128/JVI.06219-11
PMCID: PMC3302243  PMID: 22190726
22.  Is close monitoring in the intensive care unit necessary after elective liver resection? 
Purpose
Many surgical patients are admitted to the intensive care unit (ICU), resulting in an increased demand, and possible waste, of resources. Patients who undergo liver resection are also transferred postoperatively to the ICU. However, this may not be necessary in all cases. This study was designed to assess the necessity of ICU admission.
Methods
The medical records of 313 patients who underwent liver resections, as performed by a single surgeon from March 2000 to December 2010 were retrospectively reviewed.
Results
Among 313 patients, 168 patients (53.7%) were treated in the ICU. 148 patients (88.1%) received only observation during the ICU care. The ICU re-admission and intensive medical treatment significantly correlated with major liver resection (odds ratio [OR], 6.481; P = 0.011), and intraoperative transfusions (OR, 7.108; P = 0.016). Patients who underwent major liver resection and intraoperative transfusion were significantly associated with need for mechanical ventilator care, longer postoperative stays in the ICU and the hospital, and hospital mortality.
Conclusion
Most patients admitted to the ICU after major liver resection just received close monitoring. Even though patients underwent major liver resection, patients without receipt of intraoperative transfusion could be sent to the general ward. Duration of ICU/hospital stay, ventilator care and mortality significantly correlated with major liver resection and intraoperative transfusion. Major liver resection and receipt of intraoperative transfusions should be considered indicators for ICU admission.
doi:10.4174/jkss.2012.83.3.155
PMCID: PMC3433552  PMID: 22977762
Hepatectomy; Major resection; Intensive care units; Intraoperative transfusion
23.  Cyclosporine Immunomodulation Retards Regeneration of Surgically Transected Corneal Nerves 
This study shows that immunomodulation with cyclosporine reduces the expression of cytokines in the cornea and retards regenerative sprouting from transected corneal stromal nerve trunks.
Purpose.
To determine whether immunomodulation with cyclosporine (CsA) affects reinnervation after surgical transection of stromal nerves.
Methods.
Thy1-YFP+ neurofluorescent mice underwent lamellar corneal surgery and 3 days later, received artificial tears or CsA eye drops for 6 weeks. Serial in vivo wide-field stereofluorescent microscopy was performed to determine changes in nerve fiber density (NFD). Real-time quantitative PCR was performed to determine the expression of neurotrophins and cytokines (IL6 and TNF-α). Compartmental culture of trigeminal ganglion neurons was performed in Campenot devices to determine whether CsA directly affects neurite outgrowth.
Results.
Yellow fluorescent protein (YFP)–positive cells significantly increased at 3 and 7 days after surgery. The number of YFP-positive cells in the cornea was significantly lower in the CsA group than that in the control group. The percentage increase in NFD between 2 to 6 weeks was greater in the control group (80% ± 10%, P = 0.05) than that in the CsA group (39% ± 21%). The CsA group also exhibited lower expression of IL6 and TNF-α (P = 0.01). In compartmental culture experiments, neurite outgrowth toward side compartments containing CsA was significantly less (2.29 ± 0.4 mm, P = 0.01) than that toward side compartments containing vehicle (3.97 ± 0.71 mm).
Conclusions.
Immunomodulation with CsA reduces the expression of cytokines (IL6) in the cornea and retards regenerative sprouting from transected corneal stromal nerve trunks. In addition, CsA has a direct growth inhibitory action on neurites as well.
doi:10.1167/iovs.11-8445
PMCID: PMC3317418  PMID: 22205605
24.  Novel HER2 Aptamer Selectively Delivers Cytotoxic Drug to HER2-positive Breast Cancer Cells in Vitro 
Background
Aptamer-based tumor targeted drug delivery system is a promising approach that may increase the efficacy of chemotherapy and reduce the related toxicity. HER2 protein is an attractive target for tumor-specific drug delivery because of its overexpression in multiple malignancies, including breast, gastric, ovarian, and lung cancers.
Methods
In this paper, we developed a new HER2 aptamer (HB5) by using systematic evolution of ligands by exponential enrichment technology (SELEX) and exploited its role as a targeting ligand for delivering doxorubicin (Dox) to breast cancer cells in vitro.
Results
The selected aptamer was an 86-nucleotide DNA molecule that bound to an epitope peptide of HER2 with a Kd of 18.9 nM. The aptamer also bound to the extracellular domain (ECD) of HER2 protein with a Kdof 316 nM, and had minimal cross reactivity to albumin or trypsin. In addition, the aptamer was found to preferentially bind to HER2-positive but not HER2-negative breast cancer cells. An aptamer-doxorubicin complex (Apt-Dox) was formulated by intercalating Dox into the DNA structure of HB5. The Apt-Dox complex could selectively deliver Dox to HER2-positive breast cancer cells while reducing the drug intake by HER2-negative cells in vitro. Moreover, Apt-Dox retained the cytotoxicity of Dox against HER2-positive breast cancer cells, but reduced the cytotoxicity to HER2-negative cells.
Conclusions
The results suggest that the selected HER2 aptamer may have application potentials in targeted therapy against HER2-positive breast cancer cells.
doi:10.1186/1479-5876-10-148
PMCID: PMC3583217  PMID: 22817844
Aptamer; HER2; Breast cancer; Tumor targeted therapy
25.  A Surface Enolase Participates in Borrelia burgdorferi-Plasminogen Interaction and Contributes to Pathogen Survival within Feeding Ticks 
Infection and Immunity  2012;80(1):82-90.
Borrelia burgdorferi, a tick-borne bacterial pathogen, causes a disseminated infection involving multiple organs known as Lyme disease. Surface proteins can directly participate in microbial virulence by facilitating pathogen dissemination via interaction with host factors. We show here that a fraction of the B. burgdorferi chromosomal gene product BB0337, annotated as enolase or phosphopyruvate dehydratase, is associated with spirochete outer membrane and is surface exposed. B. burgdorferi enolase, either in a recombinant form or as a membrane-bound native antigen, displays enzymatic activities intrinsic to the glycolytic pathway. However, the protein also interacts with host plasminogen, potentially leading to its activation and resulting in B. burgdorferi-induced fibrinolysis. As expected, enolase displayed consistent expression in vivo, however, with a variable temporal and spatial expression during spirochete infection in mice and ticks. Despite an extracellular exposure of the antigen and a potential role in host-pathogen interaction, active immunization of mice with recombinant enolase failed to evoke protective immunity against subsequent B. burgdorferi infection. In contrast, enolase immunization of murine hosts significantly reduced the acquisition of spirochetes by feeding ticks, suggesting that the protein could have a stage-specific role in B. burgdorferi survival in the feeding vector. Strategies to interfere with the function of surface enolase could contribute to the development of novel preventive measures to interrupt the spirochete infection cycle and reduce the incidences of Lyme disease.
doi:10.1128/IAI.05671-11
PMCID: PMC3255677  PMID: 22025510

Results 1-25 (164)