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1.  ROS-induced ATF3 causes susceptibility to secondary infections during sepsis-associated immunosuppression 
Nature medicine  2011;18(1):128-134.
Sepsis, sepsis-induced hyperinflammation and subsequent sepsis-associated immunosuppression (SAIS) are important causes of death. Here we show in humans that the loss of the major reactive oxygen species (ROS) scavenger, glutathione (GSH), during SAIS directly correlates with an increase in the expression of activating transcription factor 3 (ATF3). In endotoxin-stimulated monocytes, ROS stress strongly superinduced NF-E2–related factor 2 (NRF2)–dependent ATF3. In vivo, this ROS-mediated superinduction of ATF3 protected against endotoxic shock by inhibiting innate cytokines, as Atf3−/− mice remained susceptible to endotoxic shock even under conditions of ROS stress. Although it protected against endotoxic shock, this ROS-mediated superinduction of ATF3 caused high susceptibility to bacterial and fungal infections through the suppression of interleukin 6 (IL-6). As a result, Atf3−/− mice were protected against bacterial and fungal infections, even under conditions of ROS stress, whereas Atf3−/−Il6−/− mice were highly susceptible to these infections. Moreover, in a model of SAIS, secondary infections caused considerably less mortality in Atf3−/− mice than in wild-type mice, indicating that ROS-induced ATF3 crucially determines susceptibility to secondary infections during SAIS.
doi:10.1038/nm.2557
PMCID: PMC3555699  PMID: 22179317
2.  Effects of Tamsulosin on Urinary Bladder Function and Neuronal Activity in the Voiding Centers of Rats with Cyclophosphamide-induced Overactive Bladder 
Purpose
The overactive bladder (OAB) syndrome is characterized by urgency usually with frequency and nocturia. Tamsulosin, α1-adrenergic receptor antagonist, is widely used to reduce symptoms of urinary obstruction and prostatic hyperplasia. Tamsulosin can across the blood-brain barrier. We investigated the effects of tamsulosin on the symptoms of OAB in relation to neuronal activity using rats.
Methods
Adult female Sprague-Dawley rats, weighing 250±10 g (9 weeks old), were used in this study. The animals were divided into five groups (n=8 in each group): control group, OAB-induced group, OAB-induced and 0.01 mg/kg tamsulosin-treated group, OAB-induced and 0.1 mg/kg tamsulosin-treated group, and OAB-induced and 1 mg/kg tamsulosin-treated group. OAB was induced by intraperitoneal injection of cyclophosphamide (75 mg/kg) every third day for 10 days. The rats in the tamsulosin-treated groups orally received tamsulosin once a day for 14 consecutive days at the respective dose of the groups, starting 1 day after the induction of OAB. Cystometry for bladder pressure determination, immunohistochemistry for c-Fos, nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry for nitric oxide synthase (NOS) in the neuronal voiding centers and western blot for inducible NOS in the bladder were conducted.
Results
Cyclophosphamide injection enhanced contraction pressure and time, representing the induction of OAB. Contraction pressure and time were significantly suppressed by tamsulosin treatment. c-Fos and NOS expressions in the neuronal voiding centers were enhanced by induction of OAB. OAB-induced c-Fos and NOS expressions were suppressed by tamsulosin treatment.
Conclusions
Tamsulosin exerts inhibitory effect on neuronal activation in the neuronal voiding centers of OAB. The present results suggest the possibility that tamsulosin is effective therapeutic modality for ameliorating the symptoms of OAB.
doi:10.5213/inj.2012.16.1.13
PMCID: PMC3321398  PMID: 22500249
Overactive bladder; Cyclophosphamide; Tamsulosin; Rats
3.  Comprehensive assessment of array-based platforms and calling algorithms for detection of copy number variants 
Nature Biotechnology  2011;29(6):512-520.
We have systematically compared copy number variant (CNV) detection on eleven microarrays to evaluate data quality and CNV calling, reproducibility, concordance across array platforms and laboratory sites, breakpoint accuracy and analysis tool variability. Different analytic tools applied to the same raw data typically yield CNV calls with <50% concordance. Moreover, reproducibility in replicate experiments is <70% for most platforms. Nevertheless, these findings should not preclude detection of large CNVs for clinical diagnostic purposes because large CNVs with poor reproducibility are found primarily in complex genomic regions and would typically be removed by standard clinical data curation. The striking differences between CNV calls from different platforms and analytic tools highlight the importance of careful assessment of experimental design in discovery and association studies and of strict data curation and filtering in diagnostics. The CNV resource presented here allows independent data evaluation and provides a means to benchmark new algorithms.
doi:10.1038/nbt.1852
PMCID: PMC3270583  PMID: 21552272
4.  The structure of Staphylococcus aureus phosphopantetheine adenylyltransferase in complex with 3′-phosphoadenosine 5′-phosphosulfate reveals a new ligand-binding mode 
The crystal structure of S. aureus phosphopantetheine adenylyltransferase in complex with 3′-phosphoadenosine 5′-phosphosulfate has been determined and reveals a new ligand-binding mode.
Bacterial phosphopantetheine adenylyltransferase (PPAT) catalyzes the pen­ultimate step in the coenzyme A (CoA) biosynthetic pathway. It catalyzes the reversible transfer of an adenylyl group from ATP to 4′-phosphopantetheine (Ppant) to form dephospho-CoA (dPCoA) and pyrophosphate. Previous structural studies have revealed how several ligands are recognized by bacterial PPATs. ATP, ADP, Ppant and dPCoA bind to the same binding site in a highly similar manner, while CoA binds to a partially overlapping site in a different mode. To provide further structural insights into ligand binding, the crystal structure of Staphylococcus aureus PPAT was solved in a binary complex with 3′-­phosphoadenosine 5′-phosphosulfate (PAPS). This study unexpectedly revealed a new mode of ligand binding to PPAT, thus providing potentially useful information for structure-based discovery of inhibitors of bacterial PPATs.
doi:10.1107/S1744309109036616
PMCID: PMC2765882  PMID: 19851003
3′-phosphoadenosine 5′-phosphosulfate; phosphopantetheine adenylyltransferases; coenzyme A biosynthetic pathway; Staphylococcus aureus
5.  Application of a target array Comparative Genomic Hybridization to prenatal diagnosis 
BMC Medical Genetics  2010;11:102.
Background
While conventional G-banded karyotyping still remains a gold standard in prenatal genetic diagnoses, the widespread adoption of array Comparative Genomic Hybridization (array CGH) technology for postnatal genetic diagnoses has led to increasing interest in the use of this same technology for prenatal diagnosis. We have investigated the value of our own designed DNA chip as a prenatal diagnostic tool for detecting submicroscopic deletions/duplications and chromosome aneuploidies.
Methods
We designed a target bacterial artificial chromosome (BAC)-based aCGH platform (MacArray™ M-chip), which specifically targets submicroscopic deletions/duplications for 26 known genetic syndromes of medical significance observed prenatally. To validate the DNA chip, we obtained genomic DNA from 132 reference materials generated from patients with 22 genetic diseases and 94 clinical amniocentesis samples obtained for karyotyping.
Results
In the 132 reference materials, all known genomic alterations were successfully identified. In the 94 clinical samples that were also subjected to conventional karyotyping, three cases of balanced chromosomal aberrations were not detected by aCGH. However, we identified eight cases of microdeletions in the Yq11.23 chromosomal region that were not found by conventional karyotyping. This region harbors the DAZ gene, and deletions may lead to non-obstructive spermatogenesis.
Conclusions
We have successfully designed and applied a BAC-based aCGH platform for prenatal diagnosis. This platform can be used in conjunction with conventional karyotyping and will provide rapid and accurate diagnoses for the targeted genomic regions while eliminating the need to interpret clinically-uncertain genomic regions.
doi:10.1186/1471-2350-11-102
PMCID: PMC2909938  PMID: 20576126
6.  Roles of Arrest-Defective Protein 1225 and Hypoxia-Inducible Factor 1α in Tumor Growth and Metastasis 
Background
Vascular endothelial growth factor A (VEGFA), a critical mediator of tumor angiogenesis, is a well-characterized target of hypoxia-inducible factor 1 (HIF-1). Murine arrest-defective protein 1A (mARD1A225) acetylates HIF-1α, triggering its degradation, and thus may play a role in decreased expression of VEGFA.
Methods
We generated ApcMin/+/mARD1A225 transgenic mice and quantified growth of intestinal polyps. Human gastric MKN74 and murine melanoma B16F10 cells overexpressing mARD1A225 were injected into mice, and tumor growth and metastasis were measured. VEGFA expression and microvessel density in tumors were assessed using immunohistochemistry. To evaluate the role of mARD1A225 acetylation of Lys532 in HIF-1α, we injected B16F10-mARD1A225 cell lines stably expressing mutant HIF-1α/K532R into mice and measured metastasis. All statistical tests were two-sided, and P values less than .05 were considered statistically significant.
Results
ApcMin/+/mARD1A225 transgenic mice (n = 25) had statistically significantly fewer intestinal polyps than ApcMin/+ mice (n = 21) (number of intestinal polyps per mouse: ApcMin/+ mice vs ApcMin/+/mARD1A225 transgenic mice, mean = 83.4 vs 38.0 polyps, difference = 45.4 polyps, 95% confidence interval [CI] = 41.8 to 48.6; P < .001). The growth and metastases of transplanted tumors were also statistically significantly reduced in mice injected with mARD1A225-overexpressing cells than in mice injected with control cells (P < .01). Moreover, overexpression of mARD1A225 decreased VEGFA expression and microvessel density in tumor xenografts (P < .04) and ApcMin/+ intestinal polyps (P = .001). Mutation of lysine 532 of HIF-1α in B16F10-mARD1A225 cells prevented HIF-1α degradation and inhibited the antimetastatic effect of mARD1A225 (P < .001).
Conclusion
mARD1A225 may be a novel upstream target that blocks VEGFA expression and tumor-related angiogenesis.
doi:10.1093/jnci/djq026
PMCID: PMC2841038  PMID: 20194889
7.  Survival Response and Rearrangement of Plasmid DNA of Lactococcus lactis during Long-Term Starvation 
Applied and Environmental Microbiology  2001;67(10):4594-4602.
The survival response of Lactococcus lactis during long-term starvation was investigated. The cells were cultured with different levels of glucose (the sole energy source) and either were kept in the resultant spent medium or transferred to fresh medium (without glucose) for up to 2 years. The survival of the cells during starvation was not dependent on the nature of transition phase, as expected, but on the nature of medium in which the cells were kept. The proliferation of cells, despite the apparent lack of glucose, could have been due to some cells being able to utilize the small amounts of peptides still present in the spent medium or to use energy sources provided by the breakup of dead cells. The 1- and 2-year-old cultures contained cells with vastly changed morphotypes. When these isolates were examined, it was revealed that the original plasmids present in the parent were rearranged in a certain way, and an entirely new plasmid was generated. Changes were also evident in the chromosomal DNA and in gene expression. Furthermore, all of the isolates exhibited a growth advantage relative to the parent cells when grown in energy-limiting media. When they were tested against different types of stresses, they exhibited a higher resistance against the bile salt and hydrogen peroxide stresses compared to the parent. Because of the similar changes observed in the 2-year-old isolates, a similar survival strategy may be operational in those cells that survive for that length of time.
doi:10.1128/AEM.67.10.4594-4602.2001
PMCID: PMC93208  PMID: 11571161

Results 1-7 (7)