PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (167)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
more »
1.  Constitutive activation of p38 MAPK in tumor cells contributes to osteolytic bone lesions in multiple myeloma 
Bone destruction is a hallmark of multiple myeloma and affects more than 80% of patients. However, current therapy is unable to completely cure and/or prevent bone lesions. Although it is accepted that myeloma cells mediate bone destruction by inhibition of osteoblasts and activation of osteoclasts, the underlying mechanism is still poorly understood. This study demonstrates that constitutive activation of p38 mitogen-activated protein kinase in myeloma cells is responsible for myeloma-induced osteolysis. Our results show that p38 is constitutively activated in most myeloma cell lines and primary myeloma cells from patients. Myeloma cells with high/detectable p38 activity, but not those with low/undetectable p38 activity, injected into SCID or SCID-hu mice caused bone destruction. Inhibition or knockdown of p38 in human myeloma reduced or prevented myeloma-induced osteolytic bone lesions without affecting tumor growth, survival, or homing to bone. Mechanistic studies showed that myeloma cell p38 activity inhibited osteoblastogenesis and bone formation and activated osteoclastogenesis and bone resorption in myeloma-bearing SCID mice. This study elucidates a novel molecular mechanism—sactivation of p38 signaling in myeloma cells—by which myeloma cells induce osteolytic bone lesions and indicates that targeting myeloma cell p38 may be a viable approach to treating or preventing myeloma bone disease.
doi:10.1038/leu.2012.71
PMCID: PMC3381862  PMID: 22425892
Myeloma; p38 MAPK; Osteolytic bone lesions; Osteoblastogenesis; Osteoclastogenesis
2.  Ultrasound Exposure Improves the Targeted Therapy Effects of Galactosylated Docetaxel Nanoparticles on Hepatocellular Carcinoma Xenografts 
PLoS ONE  2013;8(3):e58133.
Purpose
The distribution of targeted nanoparticles in tumor tissue is affected by a combination of various factors such as the physicochemical properties of the nanoparticles, tumor hemoperfusion and tumor vascular permeability. In this study, the impact of the biological effects of ultrasound on nanoparticle targeting to liver carcinoma was explored.
Methods
The copolymer MePEG-PLGA was used to prepare the galactosylated docetaxel nanoparticles (GDN), and the physical and chemical properties as well as the acute toxicity were then assayed. The impact of ultrasound exposure (UE) on tumor hemoperfusion was observed by contrast-enhanced ultrasonography (CEUS), and the distribution of docetaxel in tumors and liver were detected by high performance liquid chromatography (HPLC). In the GDN combined with UE treatment group, the mice were injected intravenously with GDN, followed by ultrasound exposure on the human hepatocellular carcinoma xenografts. Twenty-eight days post-administration, the tumor growth inhibition rate was calculated, and the expression of Survivin and Ki67 in tumor tissues were determined by immunohistochemistry assay and quantitative real-time PCR.
Results
The mean size of prepared liver-targeting nanoparticles GDN was 209.3 nm, and the encapsulation efficiency was 72.28%. The median lethal dose of GDN was detected as 219.5 mg/kg which was about four times higher than that of docetaxel. After ultrasound exposure, the tumor peak - base intensity difference value, examined by CEUS, increased significantly. The drug content in the tumor was 1.96 times higher than in the GDN treated control. In vivo, GDN intravenous injection combined with ultrasound exposure therapy achieved the best anti-tumor effect with a tumor growth inhibition rate of 74.2%, and the expression of Survivin and Ki67 were significantly decreased as well.
Conclusion
Ultrasound exposure can improve targeting nanoparticles accumulation in the tumor, and achieve a synergism antitumor effect on the hepatocellular carcinoma xenografts.
doi:10.1371/journal.pone.0058133
PMCID: PMC3585934  PMID: 23469265
3.  Over-expression of GAPDH in human colorectal carcinoma as a preferred target of 3-Bromopyruvate Propyl Ester 
It has long been observed that many cancer cells exhibit increased aerobic glycolysis and rely more on this pathway to generate ATP and metabolic intermediates for cell proliferation. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key enzyme in glycolysis and has been known as a housekeeping molecule. In the present study, we found that GAPDH expression was significantly up-regulated in human colorectal carcinoma tissues compared to the adjacent normal tissues, and also increased in colon cancer cell lines compared to the non-tumor colon mucosa cells in culture. The expression of GAPDH was further elevated in the liver meta-static tissues compared to the original colon cancer tissue of the same patients, suggesting that high expression of GAPDH might play an important role in colon cancer development and metastasis. Importantly, we found that 3-bromopyruvate propyl ester (3-BrOP) preferentially inhibited GAPDH and exhibited potent activity in inducing colon cancer cell death by causing severe depletion of ATP. 3-BrOP at low concentrations (1–10 μM) inhibited GAPDH and a much higher concentration (300 μM) was required to inhibit hexokinase-2. The cytotoxic effect of 3-BrOP was associated with its inhibition of GAPDH, and colon cancer cells with loss of p53 were more sensitive to this compound. Our study suggests that GAPDH may be a potential target for colon cancer therapy.
doi:10.1007/s10863-012-9420-9
PMCID: PMC3332040  PMID: 22350014
Warburg effect; GAPDH; 3-Bromopyruvate; Colon cancer; Metastasis
4.  Characteristics of Hospitalized Cases with Influenza A (H1N1)pdm09 Infection during First Winter Season of Post-Pandemic in China 
PLoS ONE  2013;8(2):e55016.
Background
Influenza A (H1N1)pdm09 (2009 H1N1) re-circulated as the predominant virus from January through February 2011 in China. National surveillance of 2009 H1N1 as a notifiable disease was maintained to monitor potential changes in disease severity from the previous season.
Methodology/Principal Findings
To describe the characteristics of hospitalized cases with 2009 H1N1 infection and analyze risk factors for severe illness during the 2010–2011winter season in China, we obtained surveillance data from hospitalized cases with 2009 H1N1 infection from November 2010 through May 2011, and reviewed medical records from 701 hospitalized cases. Age-standardized risk ratios were used to compare the age distribution of patients that were hospitalized and died due to 2009 H1N1 between the 2010–2011winter season to those during the 2009–2010 pandemic period. During the 2010–2011 winter season, children less than 5 years of age had the highest relative risk of hospitalization and death, followed by adults aged 65 years or older. Additionally, the relative risk of hospitalized cases aged 5–14 and 15–24 years was lower compared to children less than 5 years of age. During the winter season of 2010–2011, the proportions of adults aged 25 years or older for hospitalization and death were significantly higher than those during the 2009–2010 pandemic period. Being male, having a chronic medical condition, delayed hospital admission (≥3 days from onset) or delayed initiation of antiviral treatment (≥5 days from onset) were associated with severe illness among non-pregnant patients ≥2 years of age.
Conclusions/Significance
We observed a change in high risk groups for hospitalization for 2009 H1N1 during the winter months immediately following the pandemic period compared to the high risk groups identified during the pandemic period. Our nationally notifiable disease surveillance system enabled us to understand the evolving epidemiology of 2009 H1N1 infection after the pandemic period.
doi:10.1371/journal.pone.0055016
PMCID: PMC3564919  PMID: 23393563
5.  Consumption of Chinese Tea-Flavor Liquor Improves Circulating Insulin Levels without Affecting Hepatic Lipid Metabolism-Related Gene Expression in Sprague-Dawley Rats 
The Scientific World Journal  2013;2013:842343.
Objective. To examine the effect of two Chinese liquors with quite different nonalcoholic components on insulin sensitivity, tissue polyunsaturated fatty acids (PUFA), and hepatic lipid metabolism in SD rats. Methods. Thirty-three SD rats were randomized into four groups and maintained in each treatment for 10 weeks: Chinese tea-flavor liquor (TFL, n = 9), traditional Chinese liquor (TCL, n = 8), ethanol control (EC, n = 8), and water control (WC, n = 8). Results. TFL significantly decreased plasma insulin (P = 0.009) and marginally decreased Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) (P = 0.05), compared with WC. Hepatic total and n-6 PUFA compositions were significantly decreased in TFL, TCL, and EC groups compared with WC group (P < 0.05). TFL significantly increased kidney n-6 PUFA (P = 0.05) and total PUFA (P = 0.039), compared with EC group. EC group showed significant higher gene expressions of acetyl-CoA carboxylase and steroid response element-binding protein (1c and 2), while there were no significant differences of these gene expressions in TFL or TCL group compared with WC. Conclusions. TFL has a beneficial effect on metabolic disorder in relation to improved circulating insulin levels without affecting hepatic lipid metabolism-related gene expressions in rats.
doi:10.1155/2013/842343
PMCID: PMC3576800  PMID: 23476149
6.  FeoB2 Functions in Magnetosome Formation and Oxidative Stress Protection in Magnetospirillum gryphiswaldense Strain MSR-1 
Journal of Bacteriology  2012;194(15):3972-3976.
Magnetotactic bacteria (MTB) synthesize unique organelles, the magnetosomes, which are intracellular nanometer-sized, membrane-enveloped magnetite. The biomineralization of magnetosomes involves the uptake of large amounts of iron. However, the iron metabolism of MTB is not well understood. The genome of the magnetotactic bacterium Magnetospirillum gryphiswaldense strain MSR-1 contains two ferrous iron transport genes, feoB1 and feoB2. The FeoB1 protein was reported to be responsible mainly for the transport of ferrous iron and to play an accessory role in magnetosome formation. To determine the role of feoB2, we constructed an feoB2 deletion mutant (MSR-1 ΔfeoB2) and an feoB1 feoB2 double deletion mutant (MSR-1 NfeoB). The single feoB2 mutation did not affect magnetite crystal biomineralization. MSR-1 NfeoB had a significantly lower average magnetosome number per cell (∼65%) than MSR-1 ΔfeoB1, indicating that FeoB2 plays a role in magnetosome formation when the feoB1 gene is deleted. Our findings showed that FeoB1 has a greater ferrous iron transport ability than FeoB2 and revealed the differential roles of FeoB1 and FeoB2 in MSR-1 iron metabolism. Interestingly, compared to the wild type, the feoB mutants showed increased sensitivity to oxidative stress and lower activities of the enzymes superoxide dismutase and catalase, indicating that the FeoB proteins help protect bacterial cells from oxidative stress.
doi:10.1128/JB.00382-12
PMCID: PMC3416554  PMID: 22636767
7.  A study of two Chinese patients with tetrasomy and pentasomy 15q11q13 including Prader-Willi/Angelman syndrome critical region present with developmental delays and mental impairment 
BMC Medical Genetics  2013;14:9.
Background
The proximal chromosome 15q is prone to unequal crossover, leading to rearrangements. Although 15q11q13 duplications are common in patients with developmental delays and mental impairment, 15q aneusomies resulting in greater or equal to 4 copies of 15q11q13 are rare and no pentasomy 15q11q13 has been reported in the literature. Thus far, all reported high copy number 15q11q13 cases are from the West populations and no such study in Chinese patients have been documented. Dosage-response pattern of high copy number 15q11q13 on clinical presentations is still a subject for further study.
Case Presentation
In this study, we characterized two Han Chinese patients with high copy number 15q11q13. Using chromosome banding, high resolution SNP-based cytogenomic array, Fluorescence in situ hybridization, and PCR-based microsatellite analysis, we identified two patients with tetrasomy 15q11q13 and pentasomy 15q11q13. Both 15q11q13 aneusomies resulted from a maternally inherited supernumerary marker chromosome 15, and each was composed of two different sized 15q11q13 segments covering the Prader-Willi/Angelman critical region: one being about 10 Mb with breakpoints at BP1 and BP5 regions on 15q11 and 15q13, respectively, and another about 8 Mb in size with breakpoints at BP1 and BP4 regions on 15q. Both patients presented with similar clinical features that included neurodevelopmental delays, mental impairment, speech and autistic behavior, and mild dysmorphism. The patient with pentasomy 15q11q13 was more severely affected than the patient with tetrasomy 15q11q13. Low birth weight was noted in patient with pentasomy 15q1q13.
Conclusions
To the best of our knowledge, this is the first case of pentasomy 15q11q13 and the first study of high copy number 15q11q13 in Han Chinese patients. Our findings demonstrate that patients with tetrasomy and pentasomy of chromosome 15q11q13 share similar spectrum of phenotypes reported in other high copy number 15q11q13 patients in the West, and positive correlation between 15q11q13 copy number and degree of severity of clinical phenotypes. Low birth weight observed in the pentasomy 15q11q13 patient was not reported in other patients with high copy number 15q11q13. Additional studies would be necessary to further characterize high copy number 15q11q13 aneusomies.
doi:10.1186/1471-2350-14-9
PMCID: PMC3598341  PMID: 23320815
Chromosome 15; Cytogenomic array; Copy number; Pentasomy; Tetrasomy
8.  The Anorexigenic Effect of Serotonin Is Mediated by the Generation of NADPH Oxidase-Dependent ROS 
PLoS ONE  2013;8(1):e53142.
Serotonin (5-HT) is a central inhibitor of food intake in mammals. Thus far, the intracellular mechanisms for the effect of serotonin on appetite regulation remain unclear. It has been recently demonstrated that reactive oxygen species (ROS) in the hypothalamus are a crucial integrative target for the regulation of food intake. To investigate the role of ROS in the serotonin-induced anorexigenic effects, conscious mice were treated with 5-HT alone or combination with Trolox (a ROS scavenger) or Apocynin (an NADPH oxidase inhibitor) by acute intracerebroventricular injection. Both Trolox and Apocynin reversed the anorexigenic action of 5-HT and the 5-HT-induced hypothalamic ROS elevation. The mRNA and protein expression levels of pro-opiomelanocortin (POMC) were dramatically increased after ICV injection with 5-HT. The anorexigenic action of 5-HT was accompanied by markedly elevated hypothalamic MDA levels and GSH-Px activity, while the SOD activity was decreased. Moreover, 5-HT significantly increased the mRNA expression of UCP-2 but reduced the levels of UCP-3. Both Trolox and Apocynin could block the 5-HT-induced changes in UCP-2 and UCP-3 gene expression. Our study demonstrates for the first time that the anorexigenic effect of 5-HT is mediated by the generation of ROS in the hypothalamus through an NADPH oxidase-dependent pathway.
doi:10.1371/journal.pone.0053142
PMCID: PMC3541393  PMID: 23326391
9.  Effect of dietary fiber on constipation: A meta analysis 
AIM: To investigate the effect of dietary fiber intake on constipation by a meta-analysis of randomized controlled trials (RCTs).
METHODS: We searched Ovid MEDLINE (from 1946 to October 2011), Cochrane Library (2011), PubMed for articles on dietary fiber intake and constipation using the terms: constipation, fiber, cellulose, plant extracts, cereals, bran, psyllium, or plantago. References of important articles were searched manually for relevant studies. Articles were eligible for the meta-analysis if they were high-quality RCTs and reported data on stool frequency, stool consistency, treatment success, laxative use and gastrointestinal symptoms. The data were extracted independently by two researchers (Yang J and Wang HP) according to the described selection criteria. Review manager version 5 software was used for analysis and test. Weighted mean difference with 95%CI was used for quantitative data, odds ratio (OR) with 95%CI was used for dichotomous data. Both I2 statistic with a cut-off of ≥ 50% and the χ2 test with a P value < 0.10 were used to define a significant degree of heterogeneity.
RESULTS: We searched 1322 potential relevant articles, 19 of which were retrieved for further assessment, 14 studies were excluded for various reasons, five studies were included in the analysis. Dietary fiber showed significant advantage over placebo in stool frequency (OR = 1.19; 95%CI: 0.58-1.80, P < 0.05). There was no significant difference in stool consistency, treatment success, laxative use and painful defecation between the two groups. Stool frequency were reported by five RCTs, all results showed either a trend or a significant difference in favor of the treatment group, number of stools per week increased in treatment group than in placebo group (OR = 1.19; 95%CI: 0.58-1.80, P < 0.05), with no significant heterogeneity among studies (I2= 0, P = 0.77). Four studies evaluated stool consistency, one of them presented outcome in terms of percentage of hard stool, which was different from others, so we included the other three studies for analysis. Two studies reported treatment success. There was significant heterogeneity between the studies (P < 0.1, I2 > 50%). Three studies reported laxative use, quantitative data was shown in one study, and the pooled analysis of the other two studies showed no significant difference between treatment and placebo groups in laxative use (OR = 1.07; 95%CI 0.51-2.25), and no heterogeneity was found (P = 0.84, I2= 0). Three studies evaluated painful defecation: one study presented both quantitative and dichotomous data, the other two studies reported quantitative and dichotomous data separately. We used dichotomous data for analysis.
CONCLUSION: Dietary fiber intake can obviously increase stool frequency in patients with constipation. It does not obviously improve stool consistency, treatment success, laxative use and painful defecation.
doi:10.3748/wjg.v18.i48.7378
PMCID: PMC3544045  PMID: 23326148
Dietary fiber; Constipation; Meta-analysis; Stool frequency; Stool consistency
10.  Polymers with hydro-responsive topography identified using high throughput AFM of an acrylate microarray† 
Soft matter  2011;7(16):7194-7197.
Atomic force microscopy has been applied to an acrylate polymer microarray to achieve a full topographic characterisation. This process discovered a small number of hydro-responsive materials created from monomers with disparate hydrophilicities that show reversibility between pitted and protruding nanoscale topographies.
doi:10.1039/C1SM06063E
PMCID: PMC3524802  PMID: 23259005
11.  Effect of Combining Therapy with Traditional Chinese Medicine-Based Psychotherapy and Herbal Medicines in Women with Menopausal Syndrome: A Randomized Controlled Clinical Trial 
This multicenter, randomized, controlled clinical study was designed to address the effectiveness of combined traditional-Chinese-medicine- (TCM-) based psychotherapy and Chinese herbal medicine (CHM) in the treatment of menopausal syndrome. Altogether 424 eligible women diagnosed as menopausal syndrome and categorized as Kidney-Yin/Kidney-Yang deficiency pattern in TCM were randomly assigned into 4 groups and accepted TCM-based psychotherapy (PSY), CHM, PSY + CHM, or placebo therapies, respectively, for 12 weeks, and another 12 weeks were taken as the followup. Kupperman Index (KI) and the Menopause-Specific Quality of Life (MENQOL) with its four subscales (vasomotor, physical, psychosocial, and sexual) were employed for efficacy assessment. Results showed that 400 participants completed 12-week treatment, of which 380 finished the record of KI and MENQOF at week 24. The average adjusted number of KI score decreased between baseline and 12 weeks in all groups. Statistically significant differences were detected in the average adjusted change between the PSY + CHM group and placebo at overall time points (P < 0.05). No severe adverse events occurred in each group and no significant differences were indicated between any of the three groups and placebo in adverse event proportion. We concluded that TCM psychotherapy combined with CHM has a favorable outcome in treating menopausal syndrome.
doi:10.1155/2012/354145
PMCID: PMC3523610  PMID: 23304198
12.  Expansion of a Restricted Residual Host Treg Repertoire is Dependent on IL-2 Following Experimental Autologous HSCT 
European journal of immunology  2011;41(12):3467-3478.
Summary
We previously identified a population of residual Treg cells following autologous hematopoietic stem transplantation (HSCT) which rapidly undergoes significant expansion in lymphopenic transplant recipients prior to repopulation by donor de novo derived Treg cells. These CD4+Foxp3+ T cells provide protection from the development of autoimmune disease. Although ablative conditioning results in excess IL-7 and IL-15, IL-2 is typically not found at high levels following autologous HSCT. We therefore examined the role of these STAT-5 signaling cytokines in the expansion of residual Treg cells after autologous HSCT. The present studies found that residual Treg cells include surviving peripheral host Foxp3+ CD4+ T cells whose expansion was critically dependent on IL-2 which could be solely provided by surviving host cells. IL-7 was found to contribute to Treg cell homeostasis, however, not as a growth factor but rather in their persistence. In conjunction with this expansion, TCR spectratype analyses revealed that the residual host Treg cell compartment differed from that present in non-conditioned healthy mice exhibiting a limited TCR diversity. Collectively, these data indicate that the proliferation of Treg and T effector (Teff) cells post-HSCT utilize separate pools of cytokines which has important implications regarding development of clinical strategies to elicit desired immune responses in patients post-transplant.
doi:10.1002/eji.201141611
PMCID: PMC3516388  PMID: 21928285
T regulatory cell; bone marrow; transplantation; CD4+ T cells; cytokines
13.  RAD52 Variants Predict Platinum Resistance and Prognosis of Cervical Cancer 
PLoS ONE  2012;7(11):e50461.
RAD52 is an important but not well characterized homologous recombination repair gene that can bind to single-stranded DNA ends and mediate the DNA-DNA interaction necessary for the annealing of complementary DNA strands. To evaluate the role of RAD52 variants in the response of tumor cells to platinum agents, we investigated their associations with platinum resistance and prognosis in cervical cancer patients. We enrolled 154 patients with cervical squamous cell carcinoma, who had radical surgery between 2008 and 2009, and genotyped three potentially functional RAD52 variants by the SNaPshot assay. We tested in vitro platinum resistance and RAD52 expression by using the MTT and immunohistochemistry methods, respectively. In 144 cases who had genotyping data, we found that both the rs1051669 variant and RAD52 protein expression were significantly associated with carboplatin resistance (P = 0.024 and 0.028, respectively) and rs10774474 with nedaplatin resistance (P = 0.018). The rs1051669 variant was significantly associated with RAD52 protein expression (adjusted OR = 4.7, 95% CI = 1.4−16.1, P = 0.013). When these three RAD52 variants were combined, progression-free survival was lower in patients who carried at least one (≥1) variant allele compared to those without any of the variant alleles (P = 0.047). Therefore, both RAD52 variants and protein expression can predict platinum resistance, and RAD52 variants appeared to predict prognosis in cervical cancer patients. Large studies are warranted to validate these findings.
doi:10.1371/journal.pone.0050461
PMCID: PMC3510183  PMID: 23209746
14.  RNAi-Mediated Silencing of Paramyosin Expression in Trichinella spiralis Results in Impaired Viability of the Parasite 
PLoS ONE  2012;7(11):e49913.
Background
Trichinella spiralis expresses paramyosin (Ts-PMY) not only as a structural protein but also as an immunomodulatory protein to protect the worm from being attacked by host complement components. In this study, the functions of PMY in the viability and the growth development of T. spiralis were confirmed at the first time by silencing the gene function with RNA interference technique.
Methods and Findings
To understand its functions in the viability of the worm, we used RNA interference to silence the expression of Ts-pmy mRNA and protein in the parasite. Significant silencing of Ts-pmy mRNA expression in larval and adult T. spiralis was achieved by siRNA and dsRNA through soaking and electroporation. Electroporation of T. spiralis larvae with 8 µM siRNA1743 or 100 ng/µl dsRNA-PF3 resulted in 66.3% and 60.4% decrease in Ts-pmy transcript and 52.0% and 64.7% decrease in Ts-PMY protein expression, respectively, compared with larvae treated with irrelevant control siRNA or dsRNA. Larvae treated with siRNA1743 displayed significant reduction in molting (40.8%) and serious surface damage as detected with SYTOX fluorescent staining. Infection of mice with larvae electroporated with Ts-pmy siRNA1743 resulted in 37.6% decrease in adult worm burden and 23.2% decrease in muscle larvae burden compared with mice infected with control siRNA-treated larvae. In addition, adult worms recovered from mice infected with siRNA-treated larvae released 24.8% less newborn larvae.
Conclusion
It is the first time RNAi was used on T. spiralis to demonstrate that silencing PMY expression in T. spiralis significantly reduces the parasite’s viability and infectivity, further confirming that Ts-PMY plays an important role in the survival of T. spiralis and therefore is a promising target for vaccine development.
doi:10.1371/journal.pone.0049913
PMCID: PMC3503832  PMID: 23185483
15.  A Comparative Study of the Arabidopsis thaliana Guard-Cell Transcriptome and Its Modulation by Sucrose 
PLoS ONE  2012;7(11):e49641.
Microarray analysis was performed on RNA isolated from guard cells that were manually dissected from leaves of Arabidopsis. By pooling our data with those of two earlier studies on Arabidopsis guard cell protoplasts, we provide a robust view of the guard-cell transcriptome, which is rich in transcripts for transcription factors, signaling proteins, transporters, and carbohydrate-modifying enzymes. To test the hypothesis that photosynthesis-derived sugar signals guard cells to adjust stomatal opening, we determined the profile of genes expressed in guard cells from leaves that had been treated with sucrose. The results revealed that expression of 440 genes changed in guard cells in response to sucrose. Consistent with this hypothesis, these genes encoded cellular functions for photosynthesis and transport of sugars, water, amino acids, and ions. Plants of T-DNA insertion lines for 50 genes highly responsive to sucrose were examined for defects in guard cell function. Twelve genes not previously known to function in guard cells were shown to be important in leaf conductance, water-use efficiency, and/or stomate development. Of these, three are of particular interest, having shown effects in nearly every test of stomatal function without a change in stomatal density: TPS5 (At4g17770), a TRAF domain-containing protein (At1g65370), and a WD repeat–containing protein (At1g15440).
doi:10.1371/journal.pone.0049641
PMCID: PMC3504121  PMID: 23185391
16.  Forces and Torques on Rotating Spirochete Flagella 
Physical review letters  2011;107(26):268101.
Spirochetes are a unique group of motile bacteria that are distinguished by their helical or flat-wave shapes and the location of their flagella, which reside within the tiny space between the bacterial cell wall and the outer membrane (the periplasm). In Borrelia burgdorferi, rotation of the flagella produces cellular undulations that drive swimming. How these shape changes arise due to the forces and torques that act between the flagella and the cell body is unknown. It is possible that resistive forces come from friction or from fluid drag, depending on whether or not the flagella are in contact with the cell wall. Here, we consider both of these cases. By analyzing the motion of an elastic flagellum rotating in the periplasmic space, we show that the flagella are most likely separated from the bacterial cell wall by a lubricating layer of fluid. This analysis then provides drag coefficients for rotation and sliding of a flagellum within the periplasm.
PMCID: PMC3484371  PMID: 22243185
17.  Th9 cells promote antitumor immune responses in vivo 
The Journal of Clinical Investigation  2012;122(11):4160-4171.
Th9 cells are a subset of CD4+ Th cells that produce the pleiotropic cytokine IL-9. IL-9/Th9 can function as both positive and negative regulators of immune response, but the role of IL-9/Th9 in tumor immunity is unknown. We examined the role of IL-9/Th9 in a model of pulmonary melanoma in mice. Lack of IL-9 enhanced tumor growth, while tumor-specific Th9 cell treatment promoted stronger antitumor responses in both prophylactic and therapeutic models. Th9 cells also elicited strong host antitumor CD8+ CTL responses by promoting Ccl20/Ccr6-dependent recruitment of DCs to the tumor tissues. Subsequent tumor antigen delivery to the draining LN resulted in CD8+ T cell priming. In agreement with this model, Ccr6 deficiency abrogated the Th9 cell–mediated antitumor response. Our data suggest a distinct role for tumor-specific Th9 cells in provoking CD8+ CTL-mediated antitumor immunity and indicate that Th9 cell–based cancer immunotherapy may be a promising therapeutic approach.
doi:10.1172/JCI65459
PMCID: PMC3484462  PMID: 23064366
18.  Effect of sample stratification on dairy GWAS results 
BMC Genomics  2012;13:536.
Background
Artificial insemination and genetic selection are major factors contributing to population stratification in dairy cattle. In this study, we analyzed the effect of sample stratification and the effect of stratification correction on results of a dairy genome-wide association study (GWAS). Three methods for stratification correction were used: the efficient mixed-model association expedited (EMMAX) method accounting for correlation among all individuals, a generalized least squares (GLS) method based on half-sib intraclass correlation, and a principal component analysis (PCA) approach.
Results
Historical pedigree data revealed that the 1,654 contemporary cows in the GWAS were all related when traced through approximately 10–15 generations of ancestors. Genome and phenotype stratifications had a striking overlap with the half-sib structure. A large elite half-sib family of cows contributed to the detection of favorable alleles that had low frequencies in the general population and high frequencies in the elite cows and contributed to the detection of X chromosome effects. All three methods for stratification correction reduced the number of significant effects. EMMAX method had the most severe reduction in the number of significant effects, and the PCA method using 20 principal components and GLS had similar significance levels. Removal of the elite cows from the analysis without using stratification correction removed many effects that were also removed by the three methods for stratification correction, indicating that stratification correction could have removed some true effects due to the elite cows. SNP effects with good consensus between different methods and effect size distributions from USDA’s Holstein genomic evaluation included the DGAT1-NIBP region of BTA14 for production traits, a SNP 45kb upstream from PIGY on BTA6 and two SNPs in NIBP on BTA14 for protein percentage. However, most of these consensus effects had similar frequencies in the elite and average cows.
Conclusions
Genetic selection and extensive use of artificial insemination contributed to overlapped genome, pedigree and phenotype stratifications. The presence of an elite cluster of cows was related to the detection of rare favorable alleles that had high frequencies in the elite cluster and low frequencies in the remaining cows. Methods for stratification correction could have removed some true effects associated with genetic selection.
doi:10.1186/1471-2164-13-536
PMCID: PMC3496570  PMID: 23039970
19.  XZH-5 Inhibits STAT3 Phosphorylation and Enhances the Cytotoxicity of Chemotherapeutic Drugs in Human Breast and Pancreatic Cancer Cells 
PLoS ONE  2012;7(10):e46624.
Constitutive activation of Signal Transducers and Activators of Transcription 3 (STAT3) signaling is frequently detected in breast and pancreatic cancer. Inhibiting constitutive STAT3 signaling represents a promising molecular target for therapeutic approach. Using structure-based design, we developed a non-peptide cell-permeable, small molecule, termed as XZH-5, which targeted STAT3 phosphorylation. XZH-5 was found to inhibit STAT3 phosphorylation (Tyr705) and induce apoptosis in human breast and pancreatic cancer cell lines expressing elevated levels of phosphorylated STAT3. XZH-5 could also inhibit interleukin-6-induced STAT3 phosphorylation in cancer cell lines expressing low phosphorylated STAT3. Inhibition of STAT3 signaling by XZH-5 was confirmed by the down-regulation of downstream targets of STAT3, such as Cyclin D1, Bcl-2, and Survivin at mRNA level. In addition, XZH-5 inhibited colony formation, cell migration, and enhanced the cytotoxicity of chemotherapeutic drugs when combined with Doxorubicin or Gemcitabine. Our results indicate that XZH-5 may be a potential therapeutic agent for breast and pancreatic cancers with constitutive STAT3 signaling.
doi:10.1371/journal.pone.0046624
PMCID: PMC3463519  PMID: 23056374
20.  U2AF1 Mutations in Chinese Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome 
PLoS ONE  2012;7(9):e45760.
Somatic mutations of U2AF1 gene have recently been identified in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, we analyzed the frequency and clinical impact of U2AF1 mutations in a cohort of 452 Chinese patients with myeloid neoplasms. Mutations in U2AF1 were found in 2.5% (7/275) of AML and 6.3% (6/96) of MDS patients, but in none of 81 CML. All mutations were heterozygous missense mutations affecting codon S34 or Q157. There was no significant association of U2AF1 mutation with blood parameters, FAB subtypes, karyotypes and other gene mutations in AML. The overall survival (OS) of AML patients with U2AF1 mutation (median 3 months) was shorter than those without mutation (median 7 months) (P = 0.035). No difference in the OS was observed between MDS patients with and without U2AF1 mutations. Our data show that U2AF1 mutation is a recurrent event at a low frequency in AML and MDS.
doi:10.1371/journal.pone.0045760
PMCID: PMC3446943  PMID: 23029227
21.  An essential role for transcription before the MBT in Xenopus laevis 
Developmental biology  2011;357(2):478-491.
Most zygotic genes remain transcriptionally silent in Drosophila, Xenopus, and zebrafish embryos through multiple mitotic divisions until the midblastula transition (MBT). Several genes have been identified in each of these organisms that are transcribed before the MBT, but whether precocious expression of specific mRNAs is important for later development has not been examined in detail. Here, we identify a class of protein coding transcripts activated before the MBT by the maternal T-box factor VegT that are components of an established transcriptional regulatory network required for mesendoderm induction in Xenopus laevis, including the Nodal related ligands xnr5, xnr6, and derrière and the transcription factors bix4, and sox17α. Accumulation of phospho-Smad2, a hallmark of active Nodal signaling, at the onset of the MBT requires preMBT transcription and activity of xnr5 and xnr6. Furthermore, preMBT activation of the Nodal pathway is essential for mesendodermal gene expression and patterning of the embryo. Finally, xnr5 and xnr6 can also activate their own expression during cleavage stages, indicating that preMBT transcription contributes to a feed-forward system that allows robust activation of Nodal signaling at the MBT.
doi:10.1016/j.ydbio.2011.06.010
PMCID: PMC3164747  PMID: 21741375
midblastula transition (MBT); Nodal; VegT; mesoderm; Smad; zygotic gene activation (ZGA)
22.  Marine N-3 Polyunsaturated Fatty Acids Are Inversely Associated with Risk of Type 2 Diabetes in Asians: A Systematic Review and Meta-Analysis 
PLoS ONE  2012;7(9):e44525.
Background
Prospective cohort studies in relation to the associations between n-3 polyunsaturated fatty acids (PUFA) and risk of type 2 diabetes (T2D) were inconsistent. Differences in tissue n-3 PUFA compositions in subjects with and without T2D were also inconsistent in both cohort and case-control studies. We conducted a systematic review and meta-analysis of prospective cohort studies to examine the associations of fish and n-3 PUFA intake with T2D risk. The differences in tissue n-3 PUFA compositions in subjects with and without T2D were investigated based on cohort and case-control studies.
Methods and Findings
PubMed, Embase, Cochrane library, China National Knowledge Infrastructure (CNKI) and Chinese VIP database up to January 2012 was used to identify relevant studies, and reference lists from retrieved studies were reviewed. Two authors independently extracted the data. Random-effects models were used to pool the summary relative risk (RR). Twenty-four studies including 24,509 T2D patients and 545,275 participants were identified. For cohort studies, the summary RR of T2D for the highest vs lowest categories of total fish, marine n-3 PUFA and alpha-linolenic acid intake was 1.07 (95% CI: 0.91, 1.25), 1.07 (95% CI: 0.95, 1.20) and 0.93 (95% CI: 0.81, 1.07), respectively. Subgroup analyses indicated that summary RR (highest vs lowest category) of T2D for fish and marine n-3 PUFA intake was 0.89 (95% CI: 0.81, 0.98) and 0.87 (95% CI: 0.79, 0.96) for Asian populations, and 1.20 (95% CI: 1.01, 1.44) and 1.16 (95% CI: 1.04, 1.28) for Western populations. Asian subjects with T2D had significantly lower tissue compositions of C22∶6n-3 (SMD: −1.43; 95% CI: −1.75, −1.12) and total n-3 PUFA (SMD: −1.41; 95% CI: −2.23, −0.59) compared with those without T2D.
Conclusion
This systematic review and meta-analysis provides evidence that marine n-3 PUFA have beneficial effects on the prevention of T2D in Asian populations.
doi:10.1371/journal.pone.0044525
PMCID: PMC3439396  PMID: 22984522
23.  Prognostic value of pretreatment and recovery duration of cranial nerve palsy in nasopharyngeal carcinoma 
Background
The purpose of this study was to evaluate the prognostic value of cranial nerve (CN) palsy in nasopharyngeal carcinoma (NPC) patients.
Methods
A retrospective analysis was performed on CN involvement using medical records of 178 consecutive patients with histologically diagnosed, non-disseminated NPC.
Results
In 178 NPC patients with CN palsy, the 5-year survival rates were as follows: overall survival (OS), 61.0%; disease-specific survival (DSS), 69.6%; local relapse-free survival (LRFS), 75.2%; distant metastasis-free survival (DMFS), 73.4%; and disease-free survival (DFS), 55.3%. Significant differences were observed in the 5-year OS rates between patients with single and multiple CN palsy (69.8% vs. 54.3%; P = 0.033) and the OS rates between patients with different pretreatment durations (68.7% vs. 43.3%, P = 0.007). However, no significant differences were observed in OS, DSS, LRFS and DFS rates between patients with upper and lower CN palsy (P = 0.581, P = 0.792, P = 0.729 and P = 0.212, respectively). The results showed that recovery duration was an independent prognostic factor for OS (HR = 2.485; P < 0.001), DSS (HR = 2.065; P = 0.016), LRFS (HR = 3.051; P = 0.001) and DFS (HR = 2.440; P < 0.001).
Conclusions
Recovery duration is an independent prognostic factor for NPC patients with CN palsy and is related to recurrence, which leads to poor survival. Recovery duration requires close surveillance and different treatment regimens.
doi:10.1186/1748-717X-7-149
PMCID: PMC3533812  PMID: 22958729
Nasopharyngeal carcinoma; Cranial nerve involvement; Pretreatment duration; Recovery duration; Prognosis
24.  Brain Networks of Explicit and Implicit Learning 
PLoS ONE  2012;7(8):e42993.
Are explicit versus implicit learning mechanisms reflected in the brain as distinct neural structures, as previous research indicates, or are they distinguished by brain networks that involve overlapping systems with differential connectivity? In this functional MRI study we examined the neural correlates of explicit and implicit learning of artificial grammar sequences. Using effective connectivity analyses we found that brain networks of different connectivity underlie the two types of learning: while both processes involve activation in a set of cortical and subcortical structures, explicit learners engage a network that uses the insula as a key mediator whereas implicit learners evoke a direct frontal-striatal network. Individual differences in working memory also differentially impact the two types of sequence learning.
doi:10.1371/journal.pone.0042993
PMCID: PMC3432050  PMID: 22952624
25.  Prognostic relevance of melanoma antigen D1 expression in colorectal carcinoma 
Background
Melanoma antigen D1 (MAGED1) is a member of the type II melanoma antigen (MAGE) family. The down-regulation of MAGED1 expression has been shown in breast carcinoma cell lines and in glioma stem cells and may play an important role in apoptosis and anti-tumorigenesis. However, there is no report on its clinical role in colorectal cancer (CRC).
Methods
We examined the expression of MAGED1 by qPCR in colorectal cancer tissues and their adjacent non-tumorous tissues taken from 6 cases and performed Western blotting and IHC analyses. In addition, we analyzed MAGED1 expression in 285 clinicopathologically characterized colorectal cancer patients.
Results
MAGED1 expression was significantly down-regulated in colorectal cancer tissues compared with adjacent non-tumorous tissues and was associated with clinical stage (p < 0.001), T classification (p = 0.001), N classification (p < 0.001), M classification (p < 0.001) and pathologic differentiation (p = 0.002). Patients with lower MAGED1 expression had a shorter survival time than those with higher MAGED1 expression. Univariate and multivariate analyses indicated that MAGED1 expression was an independent prognostic factors (p < 0.001).
Conclusions
MAGED1 may serve as a novel prognostic biomarker of human colorectal cancer.
doi:10.1186/1479-5876-10-181
PMCID: PMC3494540  PMID: 22935435
MAGED1; Colorectal cancer; Melanoma antigen and prognosis

Results 1-25 (167)