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1.  CD8+ T Cells Specific for a Malaria Cytoplasmic Antigen Form Clusters around Infected Hepatocytes and Are Protective at the Liver Stage of Infection 
Infection and Immunity  2013;81(10):3825-3834.
Following Anopheles mosquito-mediated introduction into a human host, Plasmodium parasites infect hepatocytes and undergo intensive replication. Accumulating evidence indicates that CD8+ T cells induced by immunization with attenuated Plasmodium sporozoites can confer sterile immunity at the liver stage of infection; however, the mechanisms underlying this protection are not clearly understood. To address this, we generated recombinant Plasmodium berghei ANKA expressing a fusion protein of an ovalbumin epitope and green fluorescent protein in the cytoplasm of the parasite. We have shown that the ovalbumin epitope is presented by infected liver cells in a manner dependent on a transporter associated with antigen processing and becomes a target of specific CD8+ T cells from the T cell receptor transgenic mouse line OT-I, leading to protection at the liver stage of Plasmodium infection. We visualized the interaction between OT-I cells and infected hepatocytes by intravital imaging using two-photon microscopy. OT-I cells formed clusters around infected hepatocytes, leading to the elimination of the intrahepatic parasites and subsequent formation of large clusters of OT-I cells in the liver. Gamma interferon expressed in CD8+ T cells was dispensable for this protective response. Additionally, we found that polyclonal ovalbumin-specific memory CD8+ T cells induced by de novo immunization were able to confer sterile protection, although the threshold frequency of the protection was relatively high. These studies revealed a novel mechanism of specific CD8+ T cell-mediated protective immunity and demonstrated that proteins expressed in the cytoplasm of Plasmodium parasites can become targets of specific CD8+ T cells during liver-stage infection.
PMCID: PMC3811763  PMID: 23897612
2.  A new method for maturity-dependent fractionation of neutrophil progenitors applicable for the study of myelodysplastic syndromes 
Biomarker Research  2014;2:2.
We applied our new method, maturity-dependent fractionation of bone marrow-derived neutrophil progenitors, to a study of gene expression profiles during granulopoiesis in myelodysplastic syndromes. CD34+ cells with low density [F1], CD11b-/CD16- [F2], CD11b+/CD16- [F3] and CD11b+/CD16low [F4] with intermediate density, CD11b+/CD16int [F5] and CD11b+/CD16high [F6] with high density were isolated from six patients. Although AML1 and C/EBP-ϵ mRNA peaked at F1 and F4, respectively, in healthy individuals, C/EBP-ϵ was maximized at F2/F3 in all patients, two of whom showed simultaneous peaks of AML1 at F2. Thus, this fractionation is useful to detect mistimed induction of granulopoiesis-regulating genes in myelodysplastic syndromes.
PMCID: PMC3904161  PMID: 24451620
Myelodysplastic syndromes; AML1; C/EBP-ϵ; Granulopoiesis; Fractionation; Gene expression profile
3.  Genome engineering of mammalian haploid embryonic stem cells using the Cas9/RNA system 
PeerJ  2013;1:e230.
Haploid embryonic stem cells (ESCs) are useful for studying mammalian genes because disruption of only one allele can cause loss-of-function phenotypes. Here, we report the use of haploid ESCs and the CRISPR RNA-guided Cas9 nuclease gene-targeting system to manipulate mammalian genes. Co-transfection of haploid ESCs with vectors expressing Cas9 nuclease and single-guide RNAs (sgRNAs) targeting Tet1, Tet2, and Tet3 resulted in the complete disruption of all three genes and caused a loss-of-function phenotype with high efficiency (50%). Co-transfection of cells with vectors expressing Cas9 and sgRNAs targeting two loci on the same chromosome resulted in the creation of a large chromosomal deletion and a large inversion. Thus, the use of the CRISPR system in combination with haploid ESCs provides a powerful platform to manipulate the mammalian genome.
PMCID: PMC3883491  PMID: 24432195
CRISPR/Cas; Haploid; Embryonic stem cells; Genome engineering; Tet1; Tet2; Tet3
4.  Genetically encoded system to track histone modification in vivo 
Scientific Reports  2013;3:2436.
Post-translational histone modifications play key roles in gene regulation, development, and differentiation, but their dynamics in living organisms remain almost completely unknown. To address this problem, we developed a genetically encoded system for tracking histone modifications by generating fluorescent modification-specific intracellular antibodies (mintbodies) that can be expressed in vivo. To demonstrate, an H3 lysine 9 acetylation specific mintbody (H3K9ac-mintbody) was engineered and stably expressed in human cells. In good agreement with the localization of its target acetylation, H3K9ac-mintbody was enriched in euchromatin, and its kinetics measurably changed upon treatment with a histone deacetylase inhibitor. We also generated transgenic fruit fly and zebrafish stably expressing H3K9ac-mintbody for in vivo tracking. Dramatic changes in H3K9ac-mintbody localization during Drosophila embryogenesis could highlight enhanced acetylation at the start of zygotic transcription around mitotic cycle 7. Together, this work demonstrates the broad potential of mintbody and lays the foundation for epigenetic analysis in vivo.
PMCID: PMC3743053  PMID: 23942372
5.  Hydrogen Sulfide Is a Signaling Molecule and a Cytoprotectant 
Antioxidants & Redox Signaling  2012;17(1):45-57.
Significance: Accumulating evidence shows that hydrogen sulfide may function as a signaling molecule in processes such as neuromodulation in the brain and smooth muscle relaxation in the vascular system. It also has a cytoprotective effect, since it can protect neurons and cardiac muscle from oxidative stress and ischemia-reperfusion injury, respectively. Hydrogen sulfide can also modulate inflammation, insulin release, and angiogenesis. Recent Advances: The regulation of the activity of 3-mercaptopyruvate sulfur transferase (3MST) along with cysteine aminotransferase (CAT), one of the H2S producing pathways, has been demonstrated. The production of H2S by the pathway, which is regulated by Ca2+ and facilitated by thioredoxin and dihydrolipoic acid, is also involved in H2S signaling as well as cytoprotection. Sulfur hydration of proteins by H2S has been proposed to modulate protein functions. H2S-sensitive fluorescent probes, which enable us to measure the localization of H2S in real time, have been developed. Critical Issues: The basal concentrations of H2S have recently been measured and found to be much lower than those initially reported. However, the concentration of H2S reached in stimulated cells, as well as the regulation of H2S producing enzymes is not well understood. It has been proposed that some of the effects of H2S on the regulation of enzymes and receptors might be explained through the properties of sulfane sulfur (S0), another form of active sulfur. Future Directions: The determination of H2S concentrations in activated cells using new methods including H2S-sensitive fluorescent probes, as well as the investigation of the effects of H2S using specific inhibitors, may provide better understanding of the physiological function of this molecule. Clarifying mechanisms of H2S activity may also facilitate the development of new therapeutic compounds. Antioxid. Redox Signal. 17, 45–57.
PMCID: PMC3342561  PMID: 22229673
7.  Impairment of FOS mRNA Stabilization Following Translation Arrest in Granulocytes from Myelodysplastic Syndrome Patients 
PLoS ONE  2013;8(4):e61107.
Although quantitative and qualitative granulocyte defects have been described in myelodysplastic syndromes (MDS), the underlying molecular basis of granulocyte dysfunction in MDS is largely unknown. We recently found that FOS mRNA elevation under translation-inhibiting stimuli was significantly smaller in granulocytes from MDS patients than in healthy individuals. The aim of this study is to clarify the cause of the impaired FOS induction in MDS. We first examined the mechanisms of FOS mRNA elevation using granulocytes from healthy donors cultured with the translation inhibitor emetine. Emetine increased both transcription and mRNA stability of FOS. p38 MAPK inhibition abolished the emetine-induced increase of FOS transcription but did not affect FOS mRNA stabilization. The binding of an AU-rich element (ARE)-binding protein HuR to FOS mRNA containing an ARE in 3′UTR was increased by emetine, and the knockdown of HuR reduced the FOS mRNA stabilizing effect of emetine. We next compared the emetine-induced transcription and mRNA stabilization of FOS between MDS patients and healthy controls. Increased rates of FOS transcription by emetine were similar in MDS and controls. In the absence of emetine, FOS mRNA decayed to nearly 17% of initial levels in 45 min in both groups. In the presence of emetine, however, 76.7±19.8% of FOS mRNA remained after 45 min in healthy controls, versus 37.9±25.5% in MDS (P<0.01). To our knowledge, this is the first report demonstrating attenuation of stress-induced FOS mRNA stabilization in MDS granulocytes.
PMCID: PMC3625160  PMID: 23593403
8.  Expression of a secretory α-glucosidase II from Apis cerana indica in Pichia pastoris and its characterization 
BMC Biotechnology  2013;13:16.
α–glucosidase (HBGase) plays a key role in hydrolyzing α-glucosidic linkages. In Apis mellifera, three isoforms of HBGase (I, II and III) have been reported, which differ in their nucleotide composition, encoding amino acid sequences and enzyme kinetics. Recombinant (r)HBGase II from A. cerana indica (rAciHBGase II) was focused upon here due to the fact it is a native and economic honeybee species in Thailand. The data is compared to the two other isoforms, AciHBGase I and III from the same bee species and to the three isoforms (HBGase I, II and III) in different bee species where available.
The highest transcript expression level of AciHBGase II was found in larvae and pupae, with lower levels in the eggs of A. cerana indica but it was not found in foragers. The full-length AciHBGase II cDNA, and the predicted amino acid sequence it encodes were 1,740 bp and 579 residues, respectively. The cDNA sequence was 90% identical to that from the HBGase II from the closely related A. cerana japonica (GenBank accession # NM_FJ752630.1). The full length cDNA was directionally cloned into the pPICZαA expression vector in frame with a (His)6 encoding C terminal tag using EcoRI and KpnI compatible ends, and transformed into Pichia pastoris. Maximal expression of the rAciHBGase II–(His)6 protein was induced by 0.5% (v/v) methanol for 96 h and secreted into the culture media. The partially purified enzyme was found to have optimal α-glucosidase activity at pH 3.5 and 45°C, with > 80% activity between pH 3.5–5.0 and 40–55°C, and was stabile (> 80% activity) at pH 4–8 and at < 25–65°C. The optimal substrate was sucrose.
Like in A. mellifera, there are three isoforms of AciHBGase (I, II and III) that differ in their transcript expression pattern, nucleotide sequences and optimal enzyme conditions and kinetics.
PMCID: PMC3599193  PMID: 23419073
Apis cerana indica; α–glucosidase; Expression; Homology; Recombinant enzyme
9.  Community-based intervention to improve dietary habits and promote physical activity among older adults: a cluster randomized trial 
BMC Geriatrics  2013;13:8.
The fastest growing age group globally is older adults, and preventing the need for long-term nursing care in this group is important for social and financial reasons. A population approach to diet and physical activity through the use of social services can play an important role in prevention. This study examined the effectiveness of a social health program for community-dwelling older adults aimed at introducing and promoting physical activity in the home at each individual’s pace, helping participants maintain good dietary habits by keeping self-check sheets, and determining whether long-standing unhealthy or less-than-ideal physical and dietary habits can be changed.
This cluster randomized trial conducted at 6 community centers in an urban community involved 92 community-dwelling older adults aged 65–90 years. The intervention group (3 community centers; n = 57) participated in the social health program “Sumida TAKE10!” which is an educational program incorporating the “TAKE10!® for Older Adults” program, once every 2 weeks for 3 months. The control group (3 community centers; n=35) was subsequently provided with the same program as a crossover intervention group. The main outcome measures were changes in food intake frequency, food frequency score (FFS), dietary variety score (DVS), and frequency of walking and exercise. The secondary outcome measures were changes in self-rated health, appetite, and the Tokyo Metropolitan Institute of Gerontology (TMIG) Index of Competence score.
Compared to baseline, post-intervention food intake frequency for 6 of 10 food groups (meat, fish/shellfish, eggs, potatoes, fruits, and seaweed), FFS, and DVS were significantly increased in the intervention group, and interaction effects of FFS and DVS were seen between the two groups. No significant differences were observed between baseline and post-intervention in the control group. Frequency of walking and exercise remained unchanged in both groups, and no significant difference in improvement rate was seen between the groups. Self-rated health was significantly increased in the intervention group. Appetite and TMIG Index of Competence score were unchanged in both groups.
The social health program resulted in improved dietary habits, as measured by food intake frequency, FFS, and DVS, and may improve self-rated health among community-dwelling older adults.
Trial registration number
PMCID: PMC3560222  PMID: 23343312
Social health program; Community-dwelling older adults; Dietary variety; Physical activity; Self-rated health
10.  Hyperpolarization-activated cyclic nucleotide gated channels: a potential molecular link between epileptic seizures and Aβ generation in Alzheimer’s disease 
One of the best-characterized causative factors of Alzheimer’s disease (AD) is the generation of amyloid-β peptide (Aβ). AD subjects are at high risk of epileptic seizures accompanied by aberrant neuronal excitability, which in itself enhances Aβ generation. However, the molecular linkage between epileptic seizures and Aβ generation in AD remains unclear.
X11 and X11-like (X11L) gene knockout mice suffered from epileptic seizures, along with a malfunction of hyperpolarization-activated cyclic nucleotide gated (HCN) channels. Genetic ablation of HCN1 in mice and HCN1 channel blockage in cultured Neuro2a (N2a) cells enhanced Aβ generation. Interestingly, HCN1 levels dramatically decreased in the temporal lobe of cynomolgus monkeys (Macaca fascicularis) during aging and were significantly diminished in the temporal lobe of sporadic AD patients.
Because HCN1 associates with amyloid-β precursor protein (APP) and X11/X11L in the brain, genetic deficiency of X11/X11L may induce aberrant HCN1 distribution along with epilepsy. Moreover, the reduction in HCN1 levels in aged primates may contribute to augmented Aβ generation. Taken together, HCN1 is proposed to play an important role in the molecular linkage between epileptic seizures and Aβ generation, and in the aggravation of sporadic AD.
PMCID: PMC3524764  PMID: 23034178
11.  Bimatoprost ophthalmic solution 0.03% lowered intraocular pressure of normal-tension glaucoma with minimal adverse events 
The aim of this study was to evaluate the efficacy and safety of bimatoprost ophthalmic solution 0.03% (bimatoprost) in Japanese normal-tension glaucoma (NTG) patients with an intraocular pressure (IOP) of 18 mmHg or less.
Bimatoprost was instilled into the unilateral conjunctival sac of Japanese NTG patients with a baseline IOP of 18 mmHg or less. The time courses of IOP, conjunctival hyperemia, superficial punctate keratitis, and adverse events were examined at 2, 4, 8, and 12 weeks post bimatoprost instillation.
Thirty-two of the 38 enrolled NTG patients (mean age, 64.1 ± 12.6 years; 19 males and 19 females) completed the study, with six patients unable to complete the study (two patients discontinued because of side effects and four patients withdrew). The levels of IOP in the treated eyes were significantly reduced (P < 0.0001) from the baseline IOP levels. No significant change in IOP was observed in the fellow eyes. There were significant increases in conjunctival hyperemia. No significant superficial punctate keratitis scores were noted between the baseline and each point examined. Eyelash disorder, eyelid pigmentation, and deepening of the upper eyelid sulcus were observed in 28, six, and three eyes, respectively.
Bimatoprost effectively lowered the IOP. It was well tolerated in Japanese NTG patients, with few patients having to discontinue because of adverse events.
PMCID: PMC3460718  PMID: 23055677
intraocular pressure reduction; superficial punctate keratitis; conjunctival hyperemia; antiglaucoma drugs
12.  Localized accumulation of tubulin during semi-open mitosis in the Caenorhabditis elegans embryo 
Molecular Biology of the Cell  2012;23(9):1688-1699.
We report that free tubulin subunits in the Caenorhabditis elegans embryo accumulate in the nascent spindle region, independent of spindle formation. We propose that this newly identified mechanism of accumulation of free tubulin and other molecules at the nascent spindle region contributes to efficient assembly of the mitotic spindle.
The assembly of microtubules inside the cell is controlled both spatially and temporally. During mitosis, microtubule assembly must be activated locally at the nascent spindle region for mitotic spindle assembly to occur efficiently. In this paper, we report that mitotic spindle components, such as free tubulin subunits, accumulated in the nascent spindle region, independent of spindle formation in the Caenorhabditis elegans embryo. This accumulation coincided with nuclear envelope permeabilization, suggesting that permeabilization might trigger the accumulation. When permeabilization was induced earlier by knockdown of lamin, tubulin also accumulated earlier. The boundaries of the region of accumulation coincided with the remnant nuclear envelope, which remains after nuclear envelope breakdown in cells that undergo semi-open mitosis, such as those of C. elegans. Ran, a small GTPase protein, was required for tubulin accumulation. Fluorescence recovery after photobleaching analysis revealed that the accumulation was accompanied by an increase in the immobile fraction of free tubulin inside the remnant nuclear envelope. We propose that this newly identified mechanism of accumulation of free tubulin—and probably of other molecules—at the nascent spindle region contributes to efficient assembly of the mitotic spindle in the C. elegans embryo.
PMCID: PMC3338436  PMID: 22398724
13.  Chemical constituents and free radical scavenging activity of corn pollen collected from Apis mellifera hives compared to floral corn pollen at Nan, Thailand 
Bee pollen is composed of floral pollen mixed with nectar and bee secretion that is collected by foraging honey (Apis sp.) and stingless bees. It is rich in nutrients, such as sugars, proteins, lipids, vitamins and flavonoids, and has been ascribed antiproliferative, anti-allergenic, anti-angiogenic and free radical scavenging activities. This research aimed at a preliminary investigation of the chemical constituents and free radical scavenging activity in A. mellifera bee pollen.
Bee pollen was directly collected from A. mellifera colonies in Nan province, Thailand, in June, 2010, whilst floral corn (Zea mays L.) pollen was collected from the nearby corn fields. The pollen was then sequentially extracted with methanol, dichloromethane (DCM) and hexane, and each crude extract was tested for free radical scavenging activity using the DPPH assay, evaluating the percentage scavenging activity and the effective concentration at 50% (EC50). The most active crude fraction from the bee pollen was then further enriched for bioactive components by silica gel 60 quick and adsorption or Sephadex LH-20 size exclusion chromatography. The purity of all fractions in each step was observed by thin layer chromatography and the bioactivity assessed by the DPPH assay. The chemical structures of the most active fractions were analyzed by nuclear magnetic resonance.
The crude DCM extract of both the bee corn pollen and floral corn pollen provided the highest active free radical scavenging activity of the three solvent extracts, but it was significantly (over 28-fold) higher in the bee corn pollen (EC50 = 7.42 ± 0.12 μg/ml), than the floral corn pollen (EC50 = 212 ± 13.6% μg/ml). After fractionation to homogeneity, the phenolic hydroquinone and the flavone 7-O-R-apigenin were found as the minor and major bioactive compounds, respectively. Bee corn pollen contained a reasonably diverse array of nutritional components, including biotin (56.7 μg/100 g), invert sugar (19.9 g/100 g), vitamin A and β carotene (1.53 mg/100 g).
Bee pollen derived from corn (Z. mays), a non-toxic or edible plant, provided a better free radical scavenging activity than floral corn pollen.
PMCID: PMC3488964  PMID: 22513008
Apis mellifera; Bee corn pollen; Floral corn pollen; DPPH; Free radical scavenging activity; Nutritional components
14.  In vitro antiproliferative/cytotoxic activity on cancer cell lines of a cardanol and a cardol enriched from Thai Apis mellifera propolis 
Propolis is a complex resinous honeybee product. It is reported to display diverse bioactivities, such as antimicrobial, anti-inflammatory and anti-tumor properties, which are mainly due to phenolic compounds, and especially flavonoids. The diversity of bioactive compounds depends on the geography and climate, since these factors affect the floral diversity. Here, Apis mellifera propolis from Nan province, Thailand, was evaluated for potential anti-cancer activity.
Propolis was sequentially extracted with methanol, dichloromethane and hexane and the cytotoxic activity of each crude extract was assayed for antiproliferative/cytotoxic activity in vitro against five human cell lines derived from duet carcinoma (BT474), undifferentiated lung (Chaco), liver hepatoblastoma (Hep-G2), gastric carcinoma (KATO-III) and colon adenocarcinoma (SW620) cancers. The human foreskin fibroblast cell line (Hs27) was used as a non-transformed control. Those crude extracts that displayed antiproliferative/cytotoxic activity were then further fractionated by column chromatography using TLC-pattern and MTT-cytotoxicity bioassay guided selection of the fractions. The chemical structure of each enriched bioactive compound was analyzed by nuclear magnetic resonance and mass spectroscopy.
The crude hexane and dichloromethane extracts of propolis displayed antiproliferative/cytotoxic activities with IC50 values across the five cancer cell lines ranging from 41.3 to 52.4 μg/ml and from 43.8 to 53.5 μg/ml, respectively. Two main bioactive components were isolated, one cardanol and one cardol, with broadly similar in vitro antiproliferation/cytotoxicity IC50 values across the five cancer cell lines and the control Hs27 cell line, ranging from 10.8 to 29.3 μg/ml for the cardanol and < 3.13 to 5.97 μg/ml (6.82 - 13.0 μM) for the cardol. Moreover, both compounds induced cytotoxicity and cell death without DNA fragmentation in the cancer cells, but only an antiproliferation response in the control Hs27 cells However, these two compounds did not account for the net antiproliferation/cytotoxic activity of the crude extracts suggesting the existence of other potent compounds or synergistic interactions in the propolis extracts.
This is the first report that Thai A. mellifera propolis contains at least two potentially new compounds (a cardanol and a cardol) with potential anti-cancer bioactivity. Both could be alternative antiproliferative agents for future development as anti-cancer drugs.
PMCID: PMC3350427  PMID: 22458642
Antiproliferative activity; Apis mellifera; Propolis; Cancer cell; Cardanol; Cardol
15.  Investigating the relative efficacies of combination chemotherapy of paclitaxel/carboplatin, with or without anthracycline, for endometrial carcinoma 
Archives of Gynecology and Obstetrics  2011;285(5):1447-1453.
Recently a combination of paclitaxel and carboplatin (TC) (without an anthracycline) has begun to be used as an adjuvant or remission induction therapy, without any critical supportive evidence of its efficacy relative to a combination chemotherapy of taxane, platinum and anthracycline such as TEC (paclitaxel, epirubicin and carboplatin). The aim of our present study was to conduct the required clinical evaluations of the relative effectiveness of TC compared to TEC.
A retrospective comparison between the efficacy of TEC and TC regimens used for endometrial carcinoma at the Osaka University Hospital and the Osaka Medical Center for Cancer and Cardiovascular Diseases in Osaka, Japan, respectively, from 1999 to 2009 was performed. The clinical characteristics of the patients who received either TEC or TC were not significantly different, and TEC and TC therapies were initiated based on similar indications for chemotherapy. TEC regimen was paclitaxel (150 mg/m2), epirubicin (50 mg/m2) and carboplatin (AUC 4). TC regimen consisted of paclitaxel (175 mg/m2) and carboplatin (AUC 5).
TEC was demonstrated to provide significantly better survival than TC as an adjuvant therapy for resected Stage III/IV diseases (p = 0.017 for progression-free survival and p = 0.014 for overall survival, by the log-rank test). However, in recurrent or more advanced cases, TC and TEC demonstrated similar effects on survival (p = 0.55 for progression-free survival and p = 0.63 for overall survival).
TEC should be offered as an adjuvant therapy to Stage III/IV patients. TC may be considered for recurrent or unresectable cases as a remission induction therapy.
PMCID: PMC3325403  PMID: 22127553
Endometrial carcinoma; Platinum; Taxane; Anthracycline; Survival
16.  Trauma center accessibility for road traffic injuries in Hanoi, Vietnam 
Rapid economic growth in Vietnam over the last decade has led to an increased frequency of road traffic injury (RTI), which now represents one of the leading causes of death in the nation. Various efforts toward injury prevention have not produced a significant decline in the incidence of RTIs. Our study sought to describe the geographic distribution of RTIs in Hanoi, Vietnam and to evaluate the accessibility of trauma centers to those injured in the city.
We performed a cross-sectional study using Hanoi city police reports from 2006 to describe the epidemiology of RTIs occurring in Hanoi city. Additionally, we identified geographic patterns and determined the direct distance from injury sites to trauma centers by applying geographical information system (GIS) software. Factors associated with the accessibility of trauma centers were evaluated by multivariate regression analysis.
We mapped 1,271 RTIs in Hanoi city. About 40% of RTIs occurred among people 20-29 years of age. Additionally, 63% of RTIs were motorcycle-associated incidents. Two peak times of injury occurrence were observed: 12 am-4 pm and 8 pm-0 am. "Hot spots" of road traffic injuries/fatalities were identified in the city area and on main highways using Kernel density estimation. Interestingly, RTIs occurring along the two north-south main roads were not within easy access of trauma centers. Further, fatal cases, gender and injury mechanism were significantly associated with the distance between injury location and trauma centers.
Geographical patterns of RTIs in Hanoi city differed by gender, time, and injury mechanism; such information may be useful for injury prevention. Specifically, RTIs occurring along the two north-south main roads have lower accessibility to trauma centers, thus an emergency medical service system should be established.
PMCID: PMC3198672  PMID: 21962210
17.  A novel mechanism of microtubule length-dependent force to pull centrosomes toward the cell center 
Bioarchitecture  2011;1(2):74-79.
The centrosome is a major microtubule-organizing center in animal cells, and its intracellular positioning is critical for defining intracellular architecture. The centrosome positions itself at the cell center. Centrosome centration depends on the microtubule cytoskeleton. To accomplish robust centration regardless of the cell size or cell shape, it has been assumed that the force mediated by the microtubules depends on microtubule length. However, a concrete mechanism to generate forces to pull the centrosome in a microtubule length-dependent manner has been elusive. Recently, we successfully demonstrated that centrosome-directed movement of intracellular organelles along microtubules drives centrosome centration in the Caenorhabditis elegans early embryo. Based on this observation, we proposed the centrosome-organelle mutual pulling model in which the reaction forces of organelle transport generated along microtubules act as a driving force that pulls the centrosomes toward the cell center. This is the first experiment-based model that accounts for the microtubule length-dependent pulling force generated in the cytoplasm contributing to centrosome centration. Intriguingly, this model is consistent with a recent estimation that the pulling force is proportional to the cubic length of microtubules.
PMCID: PMC3158624  PMID: 21866267
centrosome centration; microtubule length dependency; dynein; centrosome-organelle mutual pulling model
19.  Expression of HDAC1 and CBP/p300 in human colorectal carcinomas 
Journal of Clinical Pathology  2007;60(11):1205-1210.
The histone‐modifying enzymes histone deacetylase (HDAC) and histone acetyltransferase (HAT) control gene transcriptional activation and repression in human malignancies.
To analyse the expression of HDAC/HAT‐associated molecules such as HDAC1, CREB‐binding protein (CBP) and p300 in human colorectal carcinomas, and investigate the relationship between their expression levels and clinicopathological parameters.
Expression levels of HDAC1, CBP, and p300 in human colorectal cancer were investigated by immunohistochemistry. In situ hybridisation (ISH) and reverse transcription (RT)‐PCR analyses were also carried out to confirm mRNA expression levels of these genes. Immunoreactivity was evaluated semi‐quantitatively using a staining index (SI). The relationships between the SIs and clinicopathological findings were analysed and survival curves were calculated using the Kaplan–Meier method and log‐rank tests.
The mean SIs for HDAC1, CBP, and p300 in this series of tumours were much higher than those in normal colonic mucosa. The presence of HDAC1 and CBP mRNAs on colorectal carcinoma cells as well as normal epithelial cells was confirmed by ISH analysis. A marked increase in p300 mRNA levels was detected in a majority of cases by RT‐PCR. Among the patients with colorectal cancer, overexpression of p300 (SI>11.9) correlated with a poor prognosis, whereas high CBP expression levels (SI>16.6) indicated long‐term survival.
Results showed the up‐regulation of these three histone‐modifying molecules in this series of colorectal cancers and suggested that monitoring of CBP and p300 may assist prediction of the prognosis in patients with colorectal adenocarcinoma.
PMCID: PMC2095491  PMID: 17720775
20.  Two Distinct Pathways to Development of Squamous Cell Carcinoma of the Vulva 
Journal of Skin Cancer  2010;2011:951250.
Squamous cell carcinoma (SCC) accounts for approximately 95% of the malignant tumors of the vaginal vulva and is mostly found in elderly women. The future numbers of patients with vulvar SCC is expected to rise, mainly because of the proportional increase in the average age of the general population. Two different pathways for vulvar SCC have been put forth. The first pathway is triggered by infection with a high-risk-type Human Papillomavirus (HPV). Integration of the HPV DNA into the host genome leads to the development of a typical vulvar intraepithelial neoplasia (VIN), accompanied with overexpression of p14ARF and p16INK4A. This lesion subsequently forms a warty- or basaloid-type SCC. The HPV vaccine is a promising new tool for prevention of this HPV related SCC of the vulva. The second pathway is HPV-independent. Keratinizing SCC develops within a background of lichen sclerosus (LS) through a differentiated VIN. It has a different set of genetic alterations than those in the first pathway, including p53 mutations, allelic imbalances (AI), and microsatellite instability (MSI). Further clinical and basic research is still required to understand and prevent vulvar SCC. Capsule. Two pathway for pathogenesis of squamous cell carcinoma of the value are reviewed.
PMCID: PMC3003991  PMID: 21188235
21.  Periostin advances atherosclerotic and rheumatic cardiac valve degeneration by inducing angiogenesis and MMP production in humans and rodents 
The Journal of Clinical Investigation  2010;120(7):2292-2306.
Valvular heart disease (VHD) is the term given to any disease process involving one or more of the heart valves. The condition can be congenital or acquired, for example as a result of atherosclerosis or rheumatic fever. Despite its clinical importance, the molecular mechanisms underlying VHD remain unknown. We investigated the pathophysiologic role and molecular mechanism of periostin, a protein that plays critical roles in cardiac valve development, in degenerative VHD. Unexpectedly, we found that periostin levels were drastically increased in infiltrated inflammatory cells and myofibroblasts in areas of angiogenesis in human atherosclerotic and rheumatic VHD, whereas periostin was localized to the subendothelial layer in normal valves. The expression patterns of periostin and chondromodulin I, an angioinhibitory factor that maintains cardiac valvular function, were mutually exclusive. In WT mice, a high-fat diet markedly increased aortic valve thickening, annular fibrosis, and MMP-2 and MMP-13 expression levels, concomitant with increased periostin expression; these changes were attenuated in periostin-knockout mice. In vitro and ex vivo studies revealed that periostin promoted tube formation and mobilization of ECs. Furthermore, periostin prominently increased MMP secretion from cultured valvular interstitial cells, ECs, and macrophages in a cell type–specific manner. These findings indicate that, in contrast to chondromodulin I, periostin plays an essential role in the progression of cardiac valve complex degeneration by inducing angiogenesis and MMP production.
PMCID: PMC2898587  PMID: 20551517
22.  Serum Biomarkers for Early Detection of Gynecologic Cancers 
Cancers  2010;2(2):1312-1327.
Ovarian, endometrial, and cervical cancers are three of the most common malignancies of the female reproductive organs. CA 125, historically the most reliable serum marker for ovarian cancer, is elevated in 50% of early-stage ovarian tumors. For endometrial cancers, there are no established serum markers. SCC, which is the best studied serum marker for squamous cell carcinomas, has been unreliable; SCC is elevated in cervical squamous cell carcinomas ranging from 28–85% of the time. Recent proteomics-based analyses show great promise for the discovery of new and more useful biomarkers. In this review, we will discuss the currently utilized serum tumor markers for gynecologic cancers and the novel biomarkers that are now under investigation.
PMCID: PMC3835131  PMID: 24281117
ovarian; endometrial; cervical; cancer; serum; tumor marker; CA 125; SCC; proteomics; biomarkers
23.  Focal adhesion kinase as an immunotherapeutic target 
Focal adhesion kinase (FAK) is a ubiquitously expressed non-receptor tyrosine kinase involved in cancer progression and metastasis that is found overexpressed in a large number of tumors such as breast, colon, prostate, melanoma, head and neck, lung and ovary. Thus, FAK could be an attractive tumor associated antigen (TAA) for developing immunotherapy against a broad type of malignancies. In this study, we determined whether predicted T cell epitopes from FAK would be able to induce anti-tumor immune cellular responses.
To validate FAK as a TAA recognized by CD4 helper T lymphocytes (HTL), we have combined the use of predictive peptide/MHC class II binding algorithms with in vitro vaccination of CD4 T lymphocytes from healthy individuals and melanoma patients.
Two synthetic peptides, FAK143-157 and FAK1000-1014, induced HTL responses that directly recognized FAK-expressing tumor cells and autologous dendritic cells pulsed with FAK-expressing tumor cell lysates in an HLA class II-restricted manner. Moreover, since the FAK peptides were recognized by melanoma patient’s CD4 T cells, this is indicative that T cell precursors reactive with FAK already exist in peripheral blood of these patients.
Our results provide evidence that FAK functions as a TAA and describe peptide epitopes that may be used for designing T cell-based immunotherapy for FAK-expressing cancers, which could be used in combination with newly developed FAK inhibitors.
PMCID: PMC2664392  PMID: 18941742
Focal adhesion kinase; Immunotherapy; Tumor Antigens; Major histocompatibility complex class II; CD4 helper T lymphocytes; Peptide epitope
24.  Heart failure causes cholinergic transdifferentiation of cardiac sympathetic nerves via gp130-signaling cytokines in rodents 
Although several cytokines and neurotrophic factors induce sympathetic neurons to transdifferentiate into cholinergic neurons in vitro, the physiological and pathophysiological roles of this remain unknown. During congestive heart failure (CHF), sympathetic neural tone is upregulated, but there is a paradoxical reduction in norepinephrine synthesis and reuptake in the cardiac sympathetic nervous system (SNS). Here we examined whether cholinergic transdifferentiation can occur in the cardiac SNS in rodent models of CHF and investigated the underlying molecular mechanism(s) using genetically modified mice. We used Dahl salt-sensitive rats to model CHF and found that, upon CHF induction, the cardiac SNS clearly acquired cholinergic characteristics. Of the various cholinergic differentiation factors, leukemia inhibitory factor (LIF) and cardiotrophin-1 were strongly upregulated in the ventricles of rats with CHF. Further, LIF and cardiotrophin-1 secreted from cultured failing rat cardiomyocytes induced cholinergic transdifferentiation in cultured sympathetic neurons, and this process was reversed by siRNAs targeting Lif and cardiotrophin-1. Consistent with the data in rats, heart-specific overexpression of LIF in mice caused cholinergic transdifferentiation in the cardiac SNS. Further, SNS-specific targeting of the gene encoding the gp130 subunit of the receptor for LIF and cardiotrophin-1 in mice prevented CHF-induced cholinergic transdifferentiation. Cholinergic transdifferentiation was also observed in the cardiac SNS of autopsied patients with CHF. Thus, CHF causes target-dependent cholinergic transdifferentiation of the cardiac SNS via gp130-signaling cytokines secreted from the failing myocardium.
PMCID: PMC2810079  PMID: 20051627
25.  Immunoproteasome Overexpression Underlies the Pathogenesis of Thyroid Oncocytes and Primary Hypothyroidism: Studies in Humans and Mice 
PLoS ONE  2009;4(11):e7857.
Oncocytes of the thyroid gland (Hürthle cells) are found in tumors and autoimmune diseases. They have a unique appearance characterized by abundant granular eosinophilic cytoplasm and hyperchromatic nucleus. Their pathogenesis has remained, thus far, unknown.
Methodology/Principal Findings
Using transgenic mice chronically expressing IFNγ in thyroid gland, we showed changes in the thyroid follicular epithelium reminiscent of the human oncocyte. Transcriptome analysis comparing transgenic to wild type thyrocytes revealed increased levels of immunoproteasome subunits like LMP2 in transgenics, suggesting an important role of the immunoproteasome in oncocyte pathogenesis. Pharmacologic blockade of the proteasome, in fact, ameliorated the oncocytic phenotype. Genetic deletion of LMP2 subunit prevented the development of the oncocytic phenotype and primary hypothyroidism. LMP2 was also found expressed in oncocytes from patients with Hashimoto thyroiditis and Hürthle cell tumors.
In summary, we report that oncocytes are the result of an increased immunoproteasome expression secondary to a chronic inflammatory milieu, and suggest LMP2 as a novel therapeutic target for the treatment of oncocytic lesions and autoimmune hypothyroidism.
PMCID: PMC2773418  PMID: 19924240

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